A preliminary study of a new endodontic irrigation system: Clean Jet Endo.

PubMed

Nouioua, F; Slimani, A; Levallois, B; Camps, J; Tassery, H; Cuisinier, F; Bukiet, F

2015-03-01

The purpose of the present study was to assess the irrigant penetration and cleaning ability of a new irrigation system, the Clean Jet Endo (Produits Dentaires SA, Switzerland) in comparison to conventional irrigation followed or not by sonic activation. Irrigant penetration was evaluated on resin blocks simulators by measuring the methylene blue absorbance thanks to a UV/visible spectrophotometer and cleaning ability was assessed in an ex vivo experiment according to the debris score in an artificial canal extension before and after the final irrigation protocol. A statistical analysis was carried out in order to highlight the significant differences between the irrigation techniques. Clean Jet Endo permitted to better eliminate the methylene blue into the simulated canals. A significant difference between the 2 techniques was observed in the middle third (p = 0.005) as well as in the apical third (p < 0.2). An additional microscope observation (16X) confirmed that Clean Jet Endo@ usage led to a better penetration of irrigant within the lateral canals of the simulators. Likewise, this irrigating system permitted to better eliminate the debris in the lateral groove than the other techniques. In conclusion, our findings implied the potential of this new irrigation system to enhance root canal debridement and disinfection.

Thermal Changes During Guided Flapless Implant Site Preparation: A Comparative Study.

PubMed

Sannino, Gianpaolo; Gherlone, Enrico F

To compare intrabony thermal changes induced by two different protocols for guided implant surgery during the whole drilling procedure. Two protocols for guided implant placement were evaluated in vitro using artificial bone cylinders. The control protocol provided traditional metal sleeves and a standard drilling sequence composed of four cylindrical triflute drills (cutting surface length = 16 mm). The test protocol provided a three-slot polyurethane sleeve and two cylindrical drills (second drill cutting surface length = 4 mm). Forty automated intermittent and graduated osteotomies (depth = 14 mm) were performed under external irrigation. Temperatures were measured in real time by three sensors at different depths (2, 8, and 13 mm). The temperature changes generated by the final drill of each protocol during the shearing and withdrawing processes were recorded as experimental results and subjected to the Student t test. Maximum temperature increases were recorded during the process of withdrawing in both protocols. In the control group, the mean thermal changes were 10.18°C, 8.61°C, and 5.78°C at depths of 2, 8, and 13 mm, respectively. In the test group, the mean thermal changes were 1.44°C, 4.46°C, and 3.58°C at depths of 2, 8, and 13 mm, respectively. The control group revealed statistically significantly (P < .0001) higher thermal changes than the test group, both in the superficial and deeper bone areas. An appropriate irrigation system could be crucial for thermal lowering during a guided implant osteotomy mainly in the coronal and middle third of the implant site. Copious irrigation should be provided during the withdrawing process since greater thermal increases could be expected. Lower temperature increases could be achieved, reducing drill-to-bone contact, ie, cutting surface length, due to short frictional force exposure.

Apical negative pressure irrigation versus syringe irrigation: a systematic review of cleaning and disinfection of the root canal system.

PubMed

Konstantinidi, E; Psimma, Z; Chávez de Paz, L E; Boutsioukis, C

2017-11-01

The aim of this study was to systematically review and critically analyse the published data on the treatment outcome (primary outcome) and on the cleaning and disinfection of root canals (secondary outcomes) achieved by negative pressure irrigation as compared to syringe irrigation. An electronic search was conducted in EMBASE, LILACS, PubMed, SciELO, Scopus and Web of Knowledge using both free-text keywords and controlled vocabulary. Additional studies were sought through hand searching of endodontic journals and of the relevant chapters of endodontic textbooks. No language restriction was imposed. The retrieved studies were screened by two reviewers according to predefined criteria. Included studies were critically appraised and the extracted data were arranged in tables. The electronic search and hand search retrieved 489 titles. One clinical study and 14 in vitro studies were finally included in the review; none of these studies assessed treatment outcome, four studies assessed the antimicrobial effect, seven studies evaluated the removal of pulp tissue remnants, and four studies investigated the removal of hard tissue debris or both hard tissue debris and pulp tissue remnants. Poor standardization and description of the protocols was evident. Inconclusive results were reported about the cleaning and disinfection accomplished by the two irrigation methods. Negative pressure irrigation was more effective under certain conditions when compared to suboptimal syringe irrigation; however, the variability of the protocols hindered quantitative synthesis. There is insufficient evidence to claim general superiority of any one of these methods. The level of the available evidence is low, and the conclusions should be interpreted with caution. © 2016 International Endodontic Journal. Published by John Wiley & Sons Ltd.

Comparative evaluation of postoperative pain after using endodontic needle and EndoActivator during root canal irrigation: A randomised controlled trial.

PubMed

Ramamoorthi, Surendar; Nivedhitha, Malli Sureshbabu; Divyanand, Madras Jeyaprakash

2015-08-01

The purpose of this study was to evaluate and compare the postoperative level of pain after activation of irrigants using EndoActivator with conventional needle irrigation during root canal therapy. In this prospective randomised clinical trial, 72 symptomatic irreversible pulpitis patients were selected. Based on block randomisation after routine root canal preparation, patients were assigned to two groups. In group EN, procedures were performed with endodontic irrigating needle (n = 36) while group EA received activation using EndoActivator (n = 36) in the final irrigation protocol. All the participants were called through phone at 8, 24 and 48 h to analyse pain score using visual analogue scale. Those patients who developed pain were prescribed ibuprofen 200 mg. Pain score and frequency of tablet intake were recorded and statistically analysed. Results showed that group EA resulted in significantly less postoperative pain and analgesics intake than group EN. In conclusion, within the limitations of this study, the activation of irrigants using EndoActivator can be considered an effective method for reducing postoperative pain. © 2014 Australian Society of Endodontology.

Comparison of the effect of two endodontic irrigation protocols on the elimination of bacteria from root canal system: a prospective, randomized clinical trial.

PubMed

Beus, Christopher; Safavi, Kamran; Stratton, Jeffrey; Kaufman, Blythe

2012-11-01

The purpose of this prospective, randomized clinical study was to compare the results of a nonactivated single-irrigation protocol (NAI) that used only 1% NaOCl with a passive ultrasonic multi-irrigation protocol (PUI) that used 1% NaOCl, 17% ethylenediaminetetraacetic acid, and 2% chlorhexidine in rendering canals bacteria free. In addition, the effect of a second-visit instrumentation after intra-appointment calcium hydroxide (CaOH(2)) was also evaluated in bacterial elimination. Fifty patients were recruited with a posterior tooth requiring primary endodontic treatment of apical periodontitis. Standard nonsurgical endodontic therapy was performed on both groups in a 2-visit approach by using calcium hydroxide intracanal medicament. Teeth were randomly treated with the NAI or PUI protocols in the first visit after complete instrumentation. Bacterial cultures were obtained at 4 periods during treatment from the canals: (1) before instrumentation, (2) after irrigation protocol, (3) after CaOH(2) medication, and (4) before obturation. Statistical analysis was performed on data by using the Fisher exact test and multivariate analysis. NAI and PUI rendered canals 80% and 84% bacteria free, respectively, at the end of the first visit. After CaOH(2) medication the total sample (NAI + PUI) had increased to 87% bacteria free, and the second-visit instrumentation resulted in a total of 91% bacteria free. These differences were not significant (P > .05). There was no statistical difference between irrigation methods. Each protocol resulted in a high frequency of negative cultures. This high frequency of negative cultures obtained in 1 visit is most likely related to an increased volume and depth of irrigation compared with previously reported protocols. Copyright © 2012 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

A review of mechanical move sprinkler irrigation control and automation technologies

USDA-ARS?s Scientific Manuscript database

Electronic sensors, equipment controls, and communication protocols have been developed to meet the growing interest in site-specific irrigation using center pivot and lateral move irrigation systems. Onboard and field-distributed sensors can collect data necessary for real-time irrigation manageme...

Nasal Irrigation for Chronic Rhinosinusitis and Fatigue in Patients with Gulf War Syndrome

DTIC Science & Technology

2014-07-01

xylitol has continued to provide daily use packets at no cost as indicated in the protocol and letter of support in the initial grant application...Pharmaceutical Research Center (PRC) which will be housing and dispensing all study medications ( Xylitol and Saline). We have final approval on all...recruitment strategies  Procurement of xylitol  Recruitment and enrollment of subjects 6 REPORTABLE OUTCOMES:  UW HS IRB continuing review

Estimating national crop yield potential and the relevance of weather data sources

NASA Astrophysics Data System (ADS)

Van Wart, Justin

2011-12-01

To determine where, when, and how to increase yields, researchers often analyze the yield gap (Yg), the difference between actual current farm yields and crop yield potential. Crop yield potential (Yp) is the yield of a crop cultivar grown under specific management limited only by temperature and solar radiation and also by precipitation for water limited yield potential (Yw). Yp and Yw are critical components of Yg estimations, but are very difficult to quantify, especially at larger scales because management data and especially daily weather data are scarce. A protocol was developed to estimate Yp and Yw at national scales using site-specific weather, soils and management data. Protocol procedures and inputs were evaluated to determine how to improve accuracy of Yp, Yw and Yg estimates. The protocol was also used to evaluate raw, site-specific and gridded weather database sources for use in simulations of Yp or Yw. The protocol was applied to estimate crop Yp in US irrigated maize and Chinese irrigated rice and Yw in US rainfed maize and German rainfed wheat. These crops and countries account for >20% of global cereal production. The results have significant implications for past and future studies of Yp, Yw and Yg. Accuracy of national long-term average Yp and Yw estimates was significantly improved if (i) > 7 years of simulations were performed for irrigated and > 15 years for rainfed sites, (ii) > 40% of nationally harvested area was within 100 km of all simulation sites, (iii) observed weather data coupled with satellite derived solar radiation data were used in simulations, and (iv) planting and harvesting dates were specified within +/- 7 days of farmers actual practices. These are much higher standards than have been applied in national estimates of Yp and Yw and this protocol is a substantial step in making such estimates more transparent, robust, and straightforward. Finally, this protocol may be a useful tool for understanding yield trends and directing research and development efforts aimed at providing for a secure and stable future food supply.

An evaluation of microbial leakage after using MTAD as a final irrigation.

PubMed

Ghoddusi, Jamileh; Rohani, Armita; Rashed, Tahereh; Ghaziani, Pari; Akbari, Majid

2007-02-01

Cleaning the root canal is not possible without using proper irrigation. The aim of this in vitro study was to evaluate the effect of MTAD as a final irrigant on bacterial leakage of the root canal, and its interaction with two conventional root canal sealers. We used 132 extracted human maxillary anterior teeth. The teeth were randomly divided into three experimental groups (n=40) and two groups (n=6) of positive and negative control. In group 1, the smear layer was not removed and irrigation was performed using 5.25% NaOCl. In group 2, the smear layer was removed using EDTA, and in group 3, the smear layer was removed using MTAD according to the clinical protocol of use. The teeth in each group were obturated with gutta-percha and AH-Plus or Rickert sealer. The coronal portion of each root was placed in contact with inoculum of Streptococcus mutans in Brain Heart Infusion (BHI) culture media. Each root tip was placed in one bottle containing sterile BHI. Mean duration of bacterial penetration in groups 2 and 3 was significantly greater than in group 1, but there was no significant difference between groups 2 and 3. According to our findings, it takes longer for bacteria to penetrate when either EDTA or MTAD is used for smear layer removal. The root canals obturated with AH Plus showed significantly longer duration of resistance to bacterial penetration than canals obturated with Rickert.

Wireless sensor networks for canopy temperature sensing and irrigation management

USDA-ARS?s Scientific Manuscript database

For researchers, canopy temperature measurements have proven useful in characterizing crop water stress and developing protocols for irrigation management. Today, there is heightened interest in using remote canopy temperature measurements for real-time irrigation scheduling. However, without the us...

Outdoor Irrigation Measurement and Verification Protocol

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kurnik, Charles W.; Stoughton, Kate M.; Figueroa, Jorge

This measurement and verification (M&V) protocol provides procedures for energy service companies (ESCOs) and water efficiency service companies (WESCOs) to determine water savings resulting from water conservation measures (WCMs) in energy performance contracts associated with outdoor irrigation efficiency projects. The water savings are determined by comparing the baseline water use to the water use after the WCM has been implemented. This protocol outlines the basic structure of the M&V plan, and details the procedures to use to determine water savings.

Mapping irrigated areas of Ghana using fusion of 30 m and 250 m resolution remote-sensing data

USGS Publications Warehouse

Gumma, M.K.; Thenkabail, P.S.; Hideto, F.; Nelson, A.; Dheeravath, V.; Busia, D.; Rala, A.

2011-01-01

Maps of irrigated areas are essential for Ghana's agricultural development. The goal of this research was to map irrigated agricultural areas and explain methods and protocols using remote sensing. Landsat Enhanced Thematic Mapper (ETM+) data and time-series Moderate Resolution Imaging Spectroradiometer (MODIS) data were used to map irrigated agricultural areas as well as other land use/land cover (LULC) classes, for Ghana. Temporal variations in the normalized difference vegetation index (NDVI) pattern obtained in the LULC class were used to identify irrigated and non-irrigated areas. First, the temporal variations in NDVI pattern were found to be more consistent in long-duration irrigated crops than with short-duration rainfed crops due to more assured water supply for irrigated areas. Second, surface water availability for irrigated areas is dependent on shallow dug-wells (on river banks) and dug-outs (in river bottoms) that affect the timing of crop sowing and growth stages, which was in turn reflected in the seasonal NDVI pattern. A decision tree approach using Landsat 30 m one time data fusion with MODIS 250 m time-series data was adopted to classify, group, and label classes. Finally, classes were tested and verified using ground truth data and national statistics. Fuzzy classification accuracy assessment for the irrigated classes varied between 67 and 93%. An irrigated area derived from remote sensing (32,421 ha) was 20-57% higher than irrigated areas reported by Ghana's Irrigation Development Authority (GIDA). This was because of the uncertainties involved in factors such as: (a) absence of shallow irrigated area statistics in GIDA statistics, (b) non-clarity in the irrigated areas in its use, under-development, and potential for development in GIDA statistics, (c) errors of omissions and commissions in the remote sensing approach, and (d) comparison involving widely varying data types, methods, and approaches used in determining irrigated area statistics using GIDA and remote sensing. Extensive field campaigns to help in better classification and validation of irrigated areas using high (30 m ) to very high (<5 m) resolution remote sensing data that are fused with multi temporal data like MODIS are the way forward. This is especially true in accounting for small yet contiguous patches of irrigated areas from dug-wells and dug-outs. ?? 2011 by the authors.

Effectiveness of various irrigation protocols for the removal of calcium hydroxide from artificial standardized grooves

PubMed Central

GOKTURK, Hakan; OZKOCAK, Ismail; BUYUKGEBIZ, Feyzi; DEMIR, Osman

2017-01-01

Abstract Objective The aim of this study was to investigate the ability of laser-activated irrigation (LAI), XP-endo Finisher, CanalBrush, Vibringe, passive ultrasonic irrigation (PUI), and conventional syringe irrigation systems on the removal of calcium hydroxide (CH) from simulated root canal irregularities. Material and Methods The root canals of one hundred and five extracted single-rooted teeth were instrumented using Reciproc rotary files up to size R40. The teeth were split longitudinally. Two of the three standard grooves were created in the coronal and apical section of one segment, and another in the middle part of the second segment. The standardized grooves were filled with CH and the root halves were reassembled. After 14 days, the specimens were randomly divided into 7 experimental groups (n=15/group). CH was removed as follows: Group 1: beveled needle irrigation; Group 2: double side-vented needle irrigation; Group 3: CanalBrush; Group 4: XP-endo Finisher; Group 5: Vibringe; Group 6: PUI; Group 7: LAI. The amount of remaining CH in the grooves was scored under a stereomicroscope at 20× magnification. Statistical evaluation was performed using Kruskal–Wallis and Bonferroni-Correction Mann–Whitney U tests. Results Groups 1 and 2 were the least efficient in eliminating CH from the grooves. Groups 6 and 7 eliminated more CH than the other protocols; however, no significant differences were found between these two groups (P>.05). Conclusions Nevertheless, none of the investigated protocols were able to completely remove all CH from all three root regions. LAI and PUI showed less residual CH than the other protocols from artificial grooves. PMID:28678948

Differences in disinfection protocols for root canal treatments between general dentists and endodontists: A Web-based survey.

PubMed

de Gregorio, Cesar; Arias, Ana; Navarrete, Natalia; Cisneros, Rafael; Cohenca, Nestor

2015-07-01

The purpose of this study was to determine whether differences exist in disinfection protocols between endodontists and general dentists. The authors sent an invitation to participate in a Web-based survey to 950 dentists affiliated with the Spanish Board of Dentistry. Participants responded to 9 questions about irrigation protocols and other factors related to disinfection during root canal therapy. A total of 238 (25.05%) study participants successfully completed and returned the surveys. Among these participants, 50% were general dentists and 50% were endodontists. The authors found no statistically significant differences in respondents' first choice of an irrigant solution (that is, sodium hypochlorite), but they noted statistically significant differences in the protocols used by general dentists and by endodontists in relation to the concentration of sodium hypochlorite (P = .0003), the use and type of irrigant used to remove the smear layer (P = 5.39 × 10(-10)), the use of adjuncts to irrigation (P = 5.98 × 10(-8)), the enlargement of the apical preparation when shaping a necrotic tooth (P = .001), and the maintenance of apical patency throughout the debridement and shaping procedure (P = .04). General dentists and endodontists embrace different disinfection protocols. The results of the survey demonstrated that endodontists keep up to date with protocols published in the literature, whereas general dentists use protocols learned during their dental training. Both groups of clinicians should be aware of the importance of disinfection techniques and their relationship to treatment outcomes. Controlling microorganisms during a root canal treatment, especially in cases with necrotic pulp, is essential to improve treatment outcomes. Clinicians should update their protocols and also consider referring patients to a specialist when their protocols are based on traditional techniques, especially in those cases with necrotic pulp. Copyright © 2015 American Dental Association. Published by Elsevier Inc. All rights reserved.

Effect of Duration of Irrigation with Sodium Hypochlorite in Clinical Protocol of MTAD on Removal of Smear Layer and Creating Dentinal Erosion

PubMed Central

Lotfi, Mehrdad; Moghaddam, Negar; Vosoughhosseini, Sepideh; Zand, Vahid; Saghiri, Mohammad Ali

2012-01-01

Background and aims The aim of the present study was to compare 1.3% sodium hypochlorite (NaOCl) in MTAD (mixture of tetracycline isomer, acid, and detergent) for the removal of the smear layer and induction of canal erosion. Materials and methods 38 maxillary incisors were divided in three experimental groups of 10 and two positive and negative control groups of each 4 teeth, and prepared using rotary files. In test groups, 1.3% NaOCl was used for 5, 10 and 20 minutes during preparation followed by MTAD as the final rinse. In negative control group, 5.25% NaOCl was used for 10 minutes followed by 17% Ethylenediamine Tetra-Acetic Acid (EDTA) as the final rinse. In positive control group, dis-tilled water was used for 10 minutes during preparation and then as the final rinse. The samples were examined under scan-ning electron microscope, and the smear layer and dentinal erosion scores were recorded. Results Five and 10 min groups had significant differences with 20 min group (p < 0.05). In apical third, 5 and 10 min groups had also significant differences with 20 min (p < 0.05). In the coronal thirds, when the time of irrigation with 1.3% NaOCl increased from 5 min to 20 min, erosion also increased significantly. However, 5 and 10 min groups had no signifi-cant differences with negative control group. Conclusion The use of 1.3% sodium hypochlorite for 5 and 10 minutes in the MTAD protocol removes the smear layer in the coronal and middle thirds but does not induce erosion. PMID:22991642

Nasal irrigation: From empiricism to evidence-based medicine. A review.

PubMed

Bastier, P-L; Lechot, A; Bordenave, L; Durand, M; de Gabory, L

2015-11-01

Nasal irrigation plays a non-negligible role in the treatment of numerous sinonasal pathologies and postoperative care. There is, however, a wide variety of protocols. The present review of the evidence-based literature sought objective arguments for optimization and efficacy. It emerged that large-volume low-pressure nasal douche optimizes the distribution and cleansing power of the irrigation solution in the nasal cavity. Ionic composition and pH also influence mucociliary clearance and epithelium trophicity. Seawater is less rich in sodium ions and richer in bicarbonates, potassium, calcium and magnesium than is isotonic normal saline, while alkaline pH and elevated calcium concentration optimized ciliary motility in vitro. Bicarbonates reduce secretion viscosity. Potassium and magnesium promote healing and limit local inflammation. These results show that the efficacy of nasal irrigation is multifactorial. Large-volume low-pressure nasal irrigation using undiluted seawater seems, in the present state of knowledge, to be the most effective protocol. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

Antibacterial Potential of 2.5% Sodium Hypochlorite in Distinct Irrigation Protocols on Enterococcus faecalis Biofilm.

PubMed

Alves, Denise Ramos Silveira; Cunha, Rodrigo Sanches; da Silveira Bueno, Carlos Eduardo; de Alencar, Ana Helena Gonçalves; de Araújo Estrela, Cyntia Rodrigues; dos Santos, Tatiane Oliveira; Estrela, Carlos

2015-05-01

The aim of this study was to evaluate the effect of irrigation methods on antibacterial potential of 2.5% NaOCl on Enterococcus faecalis biofilm. Enterococcus faecalis biofilms were prepared during 60 days on 48 human root canals and randomized into control and experimental groups using positive and negative pressure irrigation. Bacterial growth was analyzed using turbidity of culture medium followed by UV spectrophotometry, and scanning electron microscopy (SEM) analyses were performed. Mean and standard deviations were used for evaluate the mean optical densities associated to the number of bacteria present culture, and Scheirer-Ray-Hare (an extension of the Kruskal-Wallis test) and Tamhane test to analyze the SEM images in the groups and thirds. Significance was set at 5%. Enterococcus faecalis was still present after root canal cleaning regardless of irrigation methods or bacterial identification methods. Positive and negative pressure irrigation protocols using 2.5% NaOCl show a similar capacity to reduce E. faecalis in infected root canals.

Endodontic 'solutions' part 1: a literature review on the use of endodontic lubricants, irrigants and medicaments.

PubMed

Good, Melissa; El, Karim Ikhlas A; Hussey, David L

2012-05-01

Endodontic lubricants, irrigants and medicaments help prepare and disinfect root canal systems (RCS) but primary and secondary cases involve different microbes and therefore it is unlikely that one protocol will be effective for both case types. Each individual 'solution' or sequence of'solutions' could play a significant role in each case type, but there are no detailed published guidelines in existence. To help inform clinical practice it was decided to undertake a literature review followed by a UK and Republic of Ireland wide audit on current endodontic'solution' usage within dental schools. The literature review was undertaken under the following headings: pre-op oral rinse; file lubricants; root canal irrigants and intracanal medicaments and provides an evidence base for protocol development for both primary and retreatment cases.The audit project and the protocols developed from the findings of both the literature review and audit will be presented in Part 2.

Effects of ethylenediaminetetraacetic, etidronic and peracetic acid irrigation on human root dentine and the smear layer.

PubMed

Lottanti, S; Gautschi, H; Sener, B; Zehnder, M

2009-04-01

To evaluate the effects of ethylenediaminetetraacetic (EDTA), etidronic (EA) and peracetic acid (PA) when used in conjunction with sodium hypochlorite (NaOCl) as root canal irrigants on calcium eluted from canals, smear layer, and root dentine demineralization after instrumentation/irrigation. Single-rooted human premolars were irrigated as follows (n = 12 per group): (1) 1% NaOCl during instrumentation, deionized water after instrumentation, (2) 1% NaOCl during, 17% EDTA after instrumentation, (3) a 1 : 1-mixture of 2% NaOCl and 18% EA during and after instrumentation, and (4) 1% NaOCl during, 2.25% PA after instrumentation. Irrigant volumes and contact times were 10 mL/15 min during and 5 mL/3 min after instrumentation. The evaluated outcomes were eluted calcium by atomic absorption spectroscopy, smear-covered areas by scanning electron microscopy in secondary electron mode and apparent canal wall decalcifications on root transsections in backscatter mode. For the smear layer analysis, sclerotic dentine was taken into consideration. Results were compared using appropriate parametric and nonparametric tests, alpha = 0.05. The statistical comparison of the protocols regarding calcium elution revealed that protocol (1) yielded less calcium than (3), which yielded less than protocols (2) and (4). Most of the instrumented canal walls treated with one of the decalcifying agents were free of smear layer. Protocols (1) and (3) caused no decalcification of root dentine, whilst (2) and (4) showed substance typical demineralization patterns. The decalcifying agents under investigation were all able to remove or prevent a smear layer. However, they eroded the dentine wall differently.

New developments in water efficiency

NASA Astrophysics Data System (ADS)

Gregg, Tony T.; Dewees, Amanda; Gross, Drema; Hoffman, Bill; Strub, Dan; Watson, Matt

2006-10-01

An overview of significant new developments in water efficiency is presented in this paper. The areas covered will be legislative, regulatory, new programs or program wrinkles, new products, and new studies on the effectiveness of conservation programs. Examples include state and local level efficiency regulations in Texas; the final results of the national submetering study for apartments in the US; the US effort to adopt the IWA protocols for leak detection; new water efficient commercial products such as ET irrigation controllers, new models of efficient clothes washers, and innovative toilet designs.

Efficacy of 3D conforming nickel titanium rotary instruments in eliminating canal wall bacteria from oval-shaped root canals.

PubMed

Bortoluzzi, Eduardo A; Carlon, Daniel; Meghil, Mohamed M; El-Awady, Ahmed R; Niu, Lina; Bergeron, Brian E; Susin, Lisiane; Cutler, Christopher W; Pashley, David H; Tay, Franklin R

2015-05-01

To evaluate the effectiveness of TRUShape® 3D Conforming Files, compared with Twisted Files, in reducing bacteria load from root canal walls, in the presence or absence of irrigant agitation. Extracted human premolars with single oval-shaped canals were infected with Enterococcus faecalis. Teeth in Group I (N=10; NaOCl and QMix® 2in1 as respective initial and final irrigants) were subdivided into 4 subgroups: (A) TRUShape® instrumentation without irrigant activation; (B) TRUShape® instrumentation with sonic irrigant agitation; (C) Twisted Files without irrigant agitation; (D) Twisted Files with sonic irrigant agitation. To remove confounding factor (antimicrobial irrigants), teeth in Group II (N=10) were irrigated with sterile saline, using the same subgroup designations. Specimens before and after chemomechanical débridement were cultured for quantification of colony-forming units (CFUs). Data from each group were analyzed separately using two-factor ANOVA and Holm-Sidak multiple comparison (α=0.05). Canal wall bacteria were qualitatively examined using scanning electron microscopy (SEM) and light microscopy of Taylor-modified Brown and Brenn-stained demineralised sections. CFUs from subgroups in Group I were not significantly different (P=0.935). For Group II, both file type (P<0.001) and irrigant agitation (P<0.001) significantly affected log-reduction in CFU concentrations. The interaction of these two factors was not significant (P=0.601). Although SEM showed reduced canal wall bacteria, bacteria were present within dentinal tubules after rotary instrumentation, as revealed by light microscopy of longitudinal root sections. TRUShape® files removed significantly more canal wall bacteria than Twisted Files when used without an antibacterial irrigant; the latter is required to decontaminate dentinal tubules. Root canal disinfection should not be focused only on a mechanistic approach. Rather, the rational choice of a rotary instrumentation system should be combined with the use of well-tested antimicrobial irrigants and delivery/agitation techniques to establish a clinically realistic chemomechanical débridement protocol. Published by Elsevier Ltd.

The comparison between two irrigation regimens on the dentine wettability for an epoxy resin based sealer by measuring its contact angle formed to the irrigated dentine.

PubMed

Mohan, Rayapudi Phani; Pai, Annappa Raghavendra Vivekananda

2015-01-01

The aim was to assess the influence of two irrigation regimens having ethylenediaminetetraacetic acid (EDTA) and ethylenediaminetetraacetic acid with cetrimide (EDTAC) as final irrigants, respectively, on the dentine wettability for AH Plus sealer by comparing its contact angle formed to the irrigated dentine. Study samples were divided into two groups (n = 10). The groups were irrigated with 3% sodium hypochlorite (NaOCl) solution followed by either 17% EDTA or 17% EDTAC solution. AH Plus was mixed, and controlled volume droplet (0.1 mL) of the sealer was placed on the dried samples. The contact angle was measured using a Dynamic Contact Angle Analyzer and results were analyzed using SPSS 21.0 and 2 sample t-test. There was a significant difference in the contact angle of AH Plus formed to the dentine irrigated with the above two regimens. AH Plus showed significantly lower contact angle with the regimen having EDTAC as a final irrigant than the one with EDTA (P < 0.05). An irrigation regimen consisting of NaOCl with either EDTA or EDTAC solution as a final irrigant influences the dentine wettability and contact angle of a sealer. EDTAC as a final irrigant facilitates better dentin wettability than EDTA for AH Plus to promote its better flow and adhesion.

Evaluation of the interaction between sodium hypochlorite and several formulations containing chlorhexidine and its effect on the radicular dentin--SEM and push-out bond strength analysis.

PubMed

Graziele Magro, Miriam; Kuga, Milton Carlos; Regina Victorino, Keli; Vázquez-Garcia, Fernando Antonio; Aranda-Garcia, Arturo Javier; Faria-Junior, Norberto Batista; Faria, Gisele; Luis Shinohara, André

2014-01-01

The aim of the current study was to evaluate the presence of debris and smear layer after endodontic irrigation with different formulations of 2% chlorhexidine gluconate (CHX) and its effects on the push-out bond strength of an epoxy-based sealer on the radicular dentin. One hundred extracted human canines were prepared to F5 instrument and irrigated with 2.5% sodium hypochlorite and 17% ethylenediaminetetraacetic acid. Fifty teeth were divided into five groups (n = 10), according to the final irrigation protocol with different 2% CHX formulations: G1 (control, no final rinse irrigation), G2 (CHX solution), G3 (CHX gel), G4 (Concepsis), and G5 (CHX Plus). In sequence, the specimens were submitted to scanning electron microscopy (SEM) analysis, in the cervical-medium and medium-apical segments, to evaluate the presence of debris and smear layer. The other 50 teeth were treated equally to a SEM study, but with the root canals filled with an epoxy-based endodontic sealer and submitted to a push-out bond strength test, in the cervical, middle, and apical thirds. G2, G3, G4, and G5 provided higher precipitation of the debris and smear layer than G1 (P < 0.05), but these groups were similar to each other (P > 0.05), in both segments. The values obtained in the push out test did not differ between groups, independent of the radicular third (P > 0.05). The CHXs formulations caused precipitation of the debris and smear layer on the radicular dentin, but these residues did not interfere in the push-out bond strength of the epoxy-based sealer. Copyright © 2013 Wiley Periodicals, Inc.

Soft chelating irrigation protocol optimizes bonding quality of Resilon/Epiphany root fillings.

PubMed

De-Deus, Gustavo; Namen, Fátima; Galan, João; Zehnder, Matthias

2008-06-01

This study was designed to test the impact of either a strong (MTAD) or a soft (1-hydroxyethylidene-1, 1-bisphosphonate [HEPB]) chelating solution on the bond strength of Resilon/Epiphany root fillings. Both 17% EDTA and the omission of a chelator in the irrigation protocol were used as reference treatments. Forty extracted human upper lateral incisors were prepared using different irrigation protocols (n = 10): G1: NaOCl, G2: NaOCl + 17% EDTA, G3: NaOCl + BioPure MTAD (Dentsply/Tulsa, Tulsa, OK), and G4: NaOCl + 18% HEPB. The teeth were obturated and then prepared for micropush-out assessment using root slices of 1 mm thickness. Loading was performed on a universal testing machine at a speed of 0.5 mm/min. One-way analysis of variance and Tukey multiple comparisons were used to compare the results among the experimental groups. EDTA- and MTAD-treated samples revealed intermediate bond strength (0.3-3.6 MPa). The lowest bond strengths were achieved in NaOCl-treated samples (0.3-1.2 MPa, p < 0.05). The highest bond strength was reached in the HEBP-treated samples (3.1-6.1 MPa, p < 0.05). Under the present in vitro conditions, the soft chelating irrigation protocol (18% HEBP) optimized the bonding quality of Resilon/Epiphany (Resilon Research LLC, Madison, CT) root fillings.

Smear layer removal evaluation of different protocol of Bio Race file and XP- endo Finisher file in corporation with EDTA 17% and NaOCl.

PubMed

Zand, Vahid; Mokhtari, Hadi; Reyhani, Mohammad-Frough; Nahavandizadeh, Neda; Azimi, Shahram

2017-11-01

The aim of the present study was to compare the amount of the smear layer remaining in prepared root canals with different protocols of Bio RaCe files and XP-endo Finisher file (XPF) in association with 17% EDTA and sodium hypochlorite solution. A total of 68 extracted single-rooted teeth were randomly divided into 4 experimental groups (n=14) and two control groups (n=6). The root canals were prepared with Bio RaCe files (FKG Dentaire, Switzerland) using the crown-down technique based on manufacturer's instructions and irrigated according to the following irrigation techniques: Group 1: XPF with 2 mL of 2.5% NaOCl for 1 minute. Group 2:, XPF with 1 mL of 17% EDTA for one minute. Group 3: XPF was used for 1 minute in association with normal saline solution. Group 4: XP-endo Finisher file for 30 seconds in association with 2.5% NaOCl and 17% EDTA for 30 seconds. The negative control group: NaOCl (2.5%) was used during root canal preparation, followed by irrigation with 17% EDTA at the end of root canal preparation. The positive control group: Normal saline solution was used for irrigation during root canal preparation. In all the groups, during preparation of the root canals with Bio RaCe file, 20 mL of 2.5% NaOCl was used for root canal irrigation and at the end of the procedural steps 20 mL of normal saline solution was used as a final irrigant. The samples were analyzed under SEM at ×1000‒2000 magnification and evaluated using Torabinejad scoring system. Data were analyzed with non-parametric Kruskal-Wallis test and post hoc Mann-Whitney U test, using SPSS. Statistical significant was defined at P <0.05. The results of the study showed the least amount of the smear layer at coronal, middle and apical thirds of the root canals in groups 2, which was not significantly different from the negative control group ( P <0.5). Under the limitations of the present study, use of a combination of NaOCl and EDTA in association with XPF exhibited the best efficacy for the removal of the smear layer. Key words: Smear layer, XP-endo Finisher file, EDTA, Sodium hypochlorite.

An in vitro evaluation of various irrigation techniques for the removal of double antibiotic paste from root canal surfaces

PubMed Central

GOKTURK, Hakan; OZKOCAK, Ismail; BUYUKGEBİZ, Fevzi; DEMİR, Osman

2016-01-01

ABSTRACT Objective The aim of this study was to investigate the effectiveness of conventional syringe irrigations, passive ultrasonic irrigation (PUI), Vibringe, CanalBrush, XP-endo Finisher, and laser-activated irrigation (LAI) systems in removing double antibiotic paste (DAP) from root canals. Material and Methods One hundred five extracted single-rooted teeth were instrumented. The roots were split longitudinally. Three standard grooves were created and covered with DAP. The roots were distributed into seven groups: Group 1, beveled needle irrigation; Group 2, double side-vented needle irrigation; Group 3, CanalBrush; Group 4, XP-endo Finisher; Group 5, Vibringe; Group 6, PUI; Group 7, LAI. The amount of remaining DAP was scored under a stereomicroscope. Results Group 4, Group 6, and Group 7 removed significantly more DAP than the other protocols in the coronal region. Group 7 was more efficient in the middle region; however, no significant difference was found between Group 7 and Group 6. No differences were found between groups in the apical region either, except for the comparisons between groups 7 and 2, and groups 2 and 3. Conclusions None of the investigated protocols were able to completely remove the DAP from the grooves. The Vibringe and XP-endo Finisher systems showed results similar to those of conventional needle irrigation. PMID:28076461

Preparation Prerequisites for Effective Irrigation of Apical Root Canal: A Critical Review.

PubMed

Tziafas, Dimitrios; Alraeesi, Dana; Al Hormoodi, Reem; Ataya, Maamoun; Fezai, Hessa; Aga, Nausheen

2017-10-01

It is well recognized that disinfection of the complex root canal system at the apical root canal remains the most critical therapeutic measure to treat apical periodontitis. Observational and experimental data in relation to the anatomy of the apical root canal in different tooth types and the cross sectional diameters of the apical part of the most commonly used hand and rotary files are critically reviewed. The present data analysis confirm that the challenging issue of antibacterial efficacy of modern preparation protocols in non-surgical endodontics requires more attention to apical root canal irrigation as a balance between safety and effectiveness. Ex vivo investigations clearly indicate that a specific design of the chemo-mechanical preparation is needed at the onset of RCT, more particularly in infected teeth. Design should be based on specific anatomical parameters, and must determine the appropriate size and taper of preparation as pre-requirements for effective and safe apical irrigation. The optimal irrigation protocols might be designed on the basis of technical specifications of the preparations procedures, such as the penetration depth, the type of the needle, the required time for continuous irrigant flow, the concentration of NaOCl, and the activation parameters. Key words: Endodontics, root canal treatment, instrumentation, irrigation, apical root canal.

Effect of Peracetic Acid as A Final Rinse on Push Out Bond Strength of Root Canal Sealers to Root Dentin.

PubMed

Gaddala, Naresh; Veeramachineni, Chandrasekhar; Tummala, Muralidhar

2015-05-01

Smear layer which was formed during the instrumentation of root canals hinders the penetration of root canal sealers to root dentin and affect the bond strength of root canal sealers to root dentin. Final irrigant such as demineralizing agents are used to remove the inorganic portion of the smear layer. In the present study, peracetic acid used as a final rinse, to effect the bond strength of root canal sealers to root dentin. The purpose of the present study was to evaluate the efficacy of peracetic acid as a final irrigant on bond strength of root canal sealers to root dentin. Sixty six freshly extracted human single rooted mandibular premolars were used for this study. After decoronation the samples were instrumented with Protaper upto F3 and irrigated with 5.25% NaOcl. The teeth were then divided into three groups based on final irrigant used: Group-1(control group) Canals were irrigated with distilled water. Group-2: Canals were irrigated with peracetic acid. Group-3: Canals were irrigated with smear clear. Each group was further divided into three subgroups (n=30) based on the sealer used to obturate the canals. Subgroup-1: kerr, Subgroup-2: Apexit plus, Subgroup-3: AH PLUS. Each sealer was mixed and coated to master cone and placed in the canal. The bonding between sealer and dentin surface was evaluated using push out bond strength by universal testing machine. The mean bond strength values of each group were statistically evaluated using Two-way ANOVA followed by Tukey post-hoc test. Significant difference was found among the bond strength of the sealers. But, there is no statistically significant difference between the groups irrigated with peracetic acid and smear clear compared to control group. AH Plus showed highest bond strength irrespective of the final irrigant used. Peracetic acid when employed as final irrigant improved the bond strength of root canal sealers compared to control group but not statistically significant than smear clear.

Effect of Peracetic Acid as A Final Rinse on Push Out Bond Strength of Root Canal Sealers to Root Dentin

PubMed Central

Gaddala, Naresh; Veeramachineni, Chandrasekhar

2015-01-01

Background Smear layer which was formed during the instrumentation of root canals hinders the penetration of root canal sealers to root dentin and affect the bond strength of root canal sealers to root dentin. Final irrigant such as demineralizing agents are used to remove the inorganic portion of the smear layer. In the present study, peracetic acid used as a final rinse, to effect the bond strength of root canal sealers to root dentin. Aim The purpose of the present study was to evaluate the efficacy of peracetic acid as a final irrigant on bond strength of root canal sealers to root dentin. Materials and Methods Sixty six freshly extracted human single rooted mandibular premolars were used for this study. After decoronation the samples were instrumented with Protaper upto F3 and irrigated with 5.25% NaOcl. The teeth were then divided into three groups based on final irrigant used: Group-1(control group) Canals were irrigated with distilled water. Group-2: Canals were irrigated with peracetic acid. Group-3: Canals were irrigated with smear clear. Each group was further divided into three subgroups (n=30) based on the sealer used to obturate the canals. Subgroup-1: kerr, Subgroup-2: Apexit plus, Subgroup-3: AH PLUS. Each sealer was mixed and coated to master cone and placed in the canal. The bonding between sealer and dentin surface was evaluated using push out bond strength by universal testing machine. The mean bond strength values of each group were statistically evaluated using Two-way ANOVA followed by Tukey post-hoc test. Results Significant difference was found among the bond strength of the sealers. But, there is no statistically significant difference between the groups irrigated with peracetic acid and smear clear compared to control group. AH Plus showed highest bond strength irrespective of the final irrigant used. Conclusion Peracetic acid when employed as final irrigant improved the bond strength of root canal sealers compared to control group but not statistically significant than smear clear. PMID:26155568

Effect of photon-initiated photoacoustic streaming, passive ultrasonic, and sonic irrigation techniques on dentinal tubule penetration of irrigation solution: a confocal microscopic study.

PubMed

Akcay, Merve; Arslan, Hakan; Mese, Merve; Durmus, Nazlı; Capar, Ismail Davut

2017-09-01

The aim of this in vitro study was to evaluate the efficacy of different irrigation techniques including laser-activated irrigation using an erbium:yttrium-aluminum-garnet (Er:YAG) laser with a novel tip design (photon-induced photoacoustic streaming (PIPS)), Er:YAG laser with Preciso tip, sonic activation, and passive ultrasonic activation on the final irrigation solution penetration into dentinal tubules by using a laser scanning confocal microscope. In this study, 65 extracted single-rooted human mandibular premolars were instrumented up to size 40 and randomly divided into 5 groups (n = 13) based on the activation technique of the final irrigation solution as follows: conventional irrigation (control group), sonic activation, passive ultrasonic activation, Er:YAG-PIPS tip activation, and Er:YAG-Preciso tip activation. In each group, 5 mL of 5% NaOCl labeled with fluorescent dye was used during the activation as the final irrigation solution. Specimens were sectioned at 2.5 and 8 mm from the apex and then examined under a confocal microscope to calculate the dentinal tubule penetration area. Data were analyzed using two-way analysis of variance (ANOVA) and Tukey's post hoc tests (P = 0.05). Both Er:YAG laser (Preciso/PIPS) activations exhibited a significantly higher penetration area than the other groups (P < 0.05). Additionally, passive ultrasonic activation had significantly higher penetration than the sonic activation group and the control group. Statistically significant differences were also found between each root canal third (coronal > middle > apical) (P < 0.001). The results from the present study support the use of Er:YAG laser activation (Preciso/PIPS) to improve the effectiveness of the final irrigation procedure by increasing the irrigant penetration area into the dentinal tubules. The activation of the irrigant and the creation of the streaming with the Er:YAG laser have a positive effect on the irrigant penetration.

Review of ultrasonic irrigation in endodontics: increasing action of irrigating solutions

PubMed Central

Mozo, Sandra; Llena, Carmen

2012-01-01

Introduction: Effective irrigant delivery and agitation are prerequisites for successful endodontic treatment. Ultrasonic irrigation can be performed with or without simultaneous ultrasonic instrumentation. Existing literature reveals that ultrasonic irrigation may have a very positive effect on chemical, biological and physical debridement of the root canal system as investigated in many in vitro studies. Objective: The purpose of this review article was to summarize and discuss the available information concerning ultrasonic irrigation in endodontics. Methods: This article presents an overview of ultrasonic irrigation methods and their debridement efficacy. In this paper the relevant literature on passive ultrasonic irrigation is reviewed. Information from original scientific papers or reviews listed in MEDLINE and Cochrane were included in the review. Results: The use of ultrasound in the irrigation procedure results in improved canal cleanliness, better irrigant transfer to the canal system, soft tissue debridement, and removal of smear layer and bacteria. There are many in vitro studies, but there is a need to standardize protocols, and correlate the clinical efficacy of ultrasonic devices with improved treatment outcomes. Understanding the basis of ultrasonic irrigation is fundamental for clinicians and researchers to improve the design and use of ultrasonic irrigation. Key words:Ultrasonic irrigation, ultrasound, smear layer, endodontics. PMID:22143738

Arthroscopic synovectomy, irrigation, and debridement for treatment of septic ankle arthrosis: a systematic review and case series.

PubMed

Mankovecky, Michael R; Roukis, Thomas S

2014-01-01

Septic arthrosis of the ankle is a rare, often devastating, infection, with a high potential for morbidity and mortality. Delay in treatment can lead to cartilage erosion, painful synovitis, and osteomyelitis. Septic ankle arthrosis deserves prompt recognition and intervention. However, quality, sound, protocol-directed arthroscopic treatment of septic ankle arthrosis of the ankle has not yet been reported. We performed a systematic review of the electronic databases and other relevant peer-reviewed sources to determine the outcomes and treatment protocols associated with septic ankle arthrosis treated with arthroscopic synovectomy, irrigation, and debridement. Nine studies, involving a total of 15 ankles, met our inclusion criteria. In addition, we present the short-term outcomes of a protocol-driven arthroscopic synovial biopsy, deep culture procurement, synovectomy, irrigation, and debridement approach for 8 ankles (8 patients). To our knowledge, this would be the largest individual case series specific to arthroscopic treatment of septic ankle arthrosis. The most common infectious organism reported in the systematic review and in our case series was methicillin-sensitive Staphylococcus aureus. Arthroscopic synovectomy, irrigation, and debridement represents an acceptable treatment method for septic ankle arthrosis and demonstrated outcomes similar to the more traditional open approach, with fewer complications. Additional, appropriately weighted, randomized controlled studies with long-term follow-up are warranted. Copyright © 2014 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

Effect of Passive Ultrasonic Irrigation on Enterococcus faecalis from Root Canals: An Ex Vivo Study.

PubMed

Guerreiro-Tanomaru, Juliane Maria; Chávez-Andrade, Gisselle Moraima; de Faria-Júnior, Norberto Batista; Watanabe, Evandro; Tanomaru-Filho, Mário

2015-01-01

Endodontic irrigation aims to clean and disinfect the root canal system. Passive ultrasonic irrigation (PUI) is based on the use of an ultrasound-activated instrument into the root canal filled with irrigant. The aim of this study was to evaluate, ex vivo, the effectiveness of PUI in eliminating Enterococcus faecalis from root canals. Seventy-five extracted human single-root teeth were used. After root canal preparation, specimens were inoculated with E. faecalis and incubated at 37 °C for 21 days. Specimens were distributed into five groups (n=15), according to the irrigation method: PUI + saline solution (PUI/SS); PUI + 1% NaOCl (PUI/NaOCl); conventional needle irrigation (CNI) + saline solution (CNI/SS); CNI + 1% NaOCl (CNI/NaOCl); No irrigation (control). Microbiological samples were collected at three time points: initial (21 days after inoculation), post-irrigation (immediately after irrigation), and final (7 days after irrigation). Data were obtained in CFU mL-1 and subjected to analysis by ANOVA and Tukey's tests at 5% significance level. The post-irrigation samples did not demonstrate statistical difference between PUI/SS and CNI/SS nor between PUI/NaOCl and CNI/NaOCl (p>0.05), but PUI/NaOCl and CNI/NaOCl had lower CFU mL-1 number than the other groups (p>0.05). Statistically significant difference was observed between the initial and post-irrigation samples and between the post-irrigation and final samples (p<0.05) in all groups, except in the control. The final samples of all groups presented bacterial counts similar to the initial samples. PUI or CNI with 1% NaOCl contribute to disinfection, but are unable to eradicate E. faecalis from the root canal system.

Evaluation of triple antibiotic paste removal by different irrigation procedures.

PubMed

Berkhoff, Julie A; Chen, Paul B; Teixeira, Fabricio B; Diogenes, Anibal

2014-08-01

Regenerative endodontics aims to re-establish a functional pulp-dentin complex. First, the root canal system is disinfected primarily by irrigants and medicaments. Triple antibiotic paste (TAP), a commonly used intracanal medicament, has been shown to be directly toxic to stem cells at concentrations greater than 0.1 g/mL. Thus, its complete removal is a crucial step in regenerative endodontic procedures. We hypothesized that currently used irrigation techniques do not completely remove TAP from root canal system. TAP was radiolabeled by the incorporation of I(125), and calcium hydroxide (Ultracal; Ultradent, South Jordan, UT) was radiolabeled with Ca(45). The intracanal medicaments were placed into standardized human root segments and incubated for 28 days at 37°C. Then, canals were irrigated with EndoActivator (Dentsply, Tulsa, OK), passive ultrasonic irrigation, EndoVac (SybronEndo, Coppell, TX), or a syringe/Max-i-Probe needle (Dentsply Rinn, Elgin, IL) using a standardized irrigation protocol in a closed system. Radioactivity levels (counts per minute values) were measured for each tooth before and after the irrigation protocols. Furthermore, the canals were sequentially enlarged and dentin samples collected and evaluated for radioactivity. Data were analyzed with analysis of variance and Bonferroni post hoc testing (P < .05). Approximately 88% of the TAP was retained in the root canal system regardless of the irrigation technique used (no difference among groups). Furthermore, approximately 50% of the radiolabeled TAP was present circumferentially up to 350 μm within the dentin. Conversely, up to 98% of the radiolabeled intracanal calcium hydroxide was removed, and most residual medicament was found present in the initial 50 μm of dentin. Current irrigation techniques do not effectively remove TAP from root canal systems, possibly because of its penetration and binding into dentin. However, calcium hydroxide is effectively removed with significant less residual presence. Copyright © 2014 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Selecting and utilizing Populus and Salix for landfill covers: implications for leachate irrigation

Treesearch

Ronald S., Jr. Zalesny; Edmund O. Bauer

2007-01-01

The success of using Populus and Salix for phytoremediation has prompted further use of leachate as a combination of irrigation and fertilization for the trees. A common protocol for such efforts has been to utilize a limited number of readily-available genotypes with decades of deployment in other applications, such as fiber or...

Prospective controlled trial comparing colostomy irrigation with "spontaneous-action" method.

PubMed

Williams, N S; Johnston, D

1980-07-12

Thirty randomly selected patients with permanent colostomies entered a prospective controlled trial comparing colostomy irrigation with spontaneous action. Each patient was interviewed and examined before irrigation was begun and again after the technique had been used for three months. Each then reverted to spontaneous action for a further three months and was then reassessed. Eight patients abandoned irrigation and 22 (73%) adhered to the protocol. Irrigation caused no mishaps or complications. The mean time spent managing the stoma was 45 +/- SEM 9 min/24 hours during spontaneous action and 53 +/- 9 min/24 hours during irrigation. This difference was not significant. The numbers of bowel actions weekly were 13 +/ SEM 2 during spontaneous action and 6 +/- 1 during irrigation (p < 0.01). Irrigation reduced odour and flatus in 20 patients and enabled 12 out of 18 to stop using drugs and seven to discard their appliance. Irrigation also improved the social life of 18 patients and the working conditions of eight out of 14. These finding show that some patients may not be suitable for irrigation but that for many it is better than the conventional British method of colostomy management. With modern apparatus the technique is safe.

Prospective controlled trial comparing colostomy irrigation with "spontaneous-action" method.

PubMed Central

Williams, N S; Johnston, D

1980-01-01

Thirty randomly selected patients with permanent colostomies entered a prospective controlled trial comparing colostomy irrigation with spontaneous action. Each patient was interviewed and examined before irrigation was begun and again after the technique had been used for three months. Each then reverted to spontaneous action for a further three months and was then reassessed. Eight patients abandoned irrigation and 22 (73%) adhered to the protocol. Irrigation caused no mishaps or complications. The mean time spent managing the stoma was 45 +/- SEM 9 min/24 hours during spontaneous action and 53 +/- 9 min/24 hours during irrigation. This difference was not significant. The numbers of bowel actions weekly were 13 +/ SEM 2 during spontaneous action and 6 +/- 1 during irrigation (p < 0.01). Irrigation reduced odour and flatus in 20 patients and enabled 12 out of 18 to stop using drugs and seven to discard their appliance. Irrigation also improved the social life of 18 patients and the working conditions of eight out of 14. These finding show that some patients may not be suitable for irrigation but that for many it is better than the conventional British method of colostomy management. With modern apparatus the technique is safe. PMID:7000249

Effect of irrigation fluid temperature on body temperature during arthroscopic elbow surgery in dogs.

PubMed

Thompson, K R; MacFarlane, P D

2013-01-01

This prospective randomised clinical trial evaluated the effect of warmed irrigation fluid on body temperature in anaesthetised dogs undergoing arthroscopic elbow surgery. Nineteen dogs undergoing elbow arthroscopy were included in the study and were randomly allocated to one of two groups. Group RT received irrigation fluid at room temperature (RT) while dogs in group W received warmed (W) irrigation fluid (36°C). A standardised patient management and anaesthetic protocol was used and body temperature was measured at four time points; (T1) pre-anaesthetic examination, (T2) arrival into theatre, (T3) end of surgery and (T4) arrival into recovery. There was no significant difference in body temperature at any time point between the groups. The mean overall decrease in body temperature between pre-anaesthetic examination (T1) and return to the recovery suite (T4) was significant in both groups, with a fall of 1.06±0.58°C (p<0.001) in group RT and 1.53±0.76°C (p<0.001) group W. There was no significant difference between the groups. At the end of surgery (T3) 4/19 (21.1%) of dogs were hypothermic (<37°C). The addition of warmed irrigation fluids to a temperature management protocol in dogs undergoing elbow arthroscopy during general anaesthesia did not lead to decreased temperature losses.

Effect of irrigation fluid temperature on body temperature during arthroscopic elbow surgery in dogs

PubMed Central

Thompson, K.R.; MacFarlane, P.D.

2013-01-01

This prospective randomised clinical trial evaluated the effect of warmed irrigation fluid on body temperature in anaesthetised dogs undergoing arthroscopic elbow surgery. Nineteen dogs undergoing elbow arthroscopy were included in the study and were randomly allocated to one of two groups. Group RT received irrigation fluid at room temperature (RT) while dogs in group W received warmed (W) irrigation fluid (36°C). A standardised patient management and anaesthetic protocol was used and body temperature was measured at four time points; (T1) pre-anaesthetic examination, (T2) arrival into theatre, (T3) end of surgery and (T4) arrival into recovery. There was no significant difference in body temperature at any time point between the groups. The mean overall decrease in body temperature between pre-anaesthetic examination (T1) and return to the recovery suite (T4) was significant in both groups, with a fall of 1.06±0.58°C (p<0.001) in group RT and 1.53±0.76°C (p<0.001) group W. There was no significant difference between the groups. At the end of surgery (T3) 4/19 (21.1%) of dogs were hypothermic (<37°C). The addition of warmed irrigation fluids to a temperature management protocol in dogs undergoing elbow arthroscopy during general anaesthesia did not lead to decreased temperature losses. PMID:26623323

Simple Wound Irrigation in the Postoperative Treatment for Surgically Drained Spontaneous Soft Tissue Abscesses: Study Protocol for a Prospective, Single-Blinded, Randomized Controlled Trial.

PubMed

Rühle, Annika; Oehme, Florian; Börnert, Katja; Fourie, Lana; Babst, Reto; Link, Björn-Christian; Metzger, Jürg; Beeres, Frank Jp

2017-05-01

Skin abscesses are a frequent encountered health care problem and lead to a significant source of morbidity. They consequently have an essential impact on the quality of life and work. To date, the type of aftercare for surgically drained abscesses remains under debate. This leads to undesirable practice variations. Many clinical standard protocols include sterile wound dressings twice a day by a home-care service to reduce the chance of a recurrent wound infection. It is unknown, however, whether reinfection rates are comparable to adequate wound irrigation with a nonsterile solution performed by the patient. Our hypothesis is that simple wound irrigation with nonsterile water for postoperative wound care after an abscess is surgically drained is feasible. We assume that in terms of reinfection and reintervention rates unsterile wound irrigation is equal to sterile wound irrigation. The primary aim of this study is therefore to investigate if there is a need for sterile wound irrigation after surgically drained spontaneous skin abscesses. In a prospective, randomized controlled, single-blinded, single-center trial based on a noninferiority design, we will enroll 128 patients randomized to either the control or the intervention group. The control group will be treated according to our current, standard protocol in which all patients receive a sterile wound irrigation performed by a home-care service twice a day. Patients randomized to the intervention group will be treated with a nonsterile wound irrigation (shower) twice a day. All patients will have a routine clinical control visit after 1, 3, 6, and 12 weeks in the outpatient clinic. Primary outcome is the reinfection and reoperation rate due to insufficient wound healing diagnosed either at the outpatient control visit or during general practitioner visits. Secondary outcome measures include a Short Form Health Survey, Visual Analog Scale, Patient and Observer Scar Assessment Scale, Vancouver Scar Scale, and the EurolQol 5-Dimension Questionnaire. Those questionnaires will be completed at the outpatient control visits. The trial was started in June 2016 and enrolled 50 patients by article publication. Regarding the adherence to our protocol, we found 10% of loss to follow-up until now. Only 2 patients needed reoperation and only 1 patient needed a change of treatment (antiseptic therapy). Most patients are happy with their randomized treatment but as expected some patients in the sterile group complained about timing problems with their working hours and home-care service appointments. Most patients in the nonsterile group are satisfied being able to take care of their wounds independently although some patients still depend on the home-care service for the wound dressing. We are hoping to have enrolled enough patients by summer 2017. The follow-up will take until autumn 2017, and study results are expected to be published by the end of 2017. This trial is solely supported by the cantonal hospital of Lucerne. Nonsterile wound irrigation is more likely to be carried out independently by the patient than sterile wound irrigation. Therefore, if nonsterile wound care shows comparable results in terms of reinfection and reintervention rates, patient independence in the aftercare of surgically drained abscesses will increase, patients can return to work earlier, and health care costs can be reduced. In a preliminary, conservative estimation of health care costs, an annual savings of 300,000 CHF will be achieved in our hospital. German Clinical Trials Register DRKS00010418; https://drks-neu.uniklinik-freiburg.de/ drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00010418 (Archived by WebCite at http://www.webcitation.org/6q0AXp5EX). ©Annika Rühle, Florian Oehme, Katja Börnert, Lana Fourie, Reto Babst, Björn-Christian Link, Jürg Metzger, Frank JP Beeres. Originally published in JMIR Research Protocols (http://www.researchprotocols.org), 01.05.2017.

Bond strength of epoxy resin-based root canal sealer to human root dentin irradiated with Er,Cr:YSGG laser.

PubMed

Franceschini, Keila de Almeida; Silva-Sousa, Yara Teresinha Corrêa; Lopes, Fabiane Carneiro; Pereira, Rodrigo Dantas; Palma-Dibb, Regina Guenka; de Sousa-Neto, Manoel Damião

2016-12-01

The aim was to evaluate the influence of Er,Cr:YSGG laser irradiation associated with different final irrigation protocols on the bond strength of epoxy resin-based root canal sealer to root dentin, on the dentin/filling material interface and in the temperature variation during irradiation. Ninety-six maxillary canines were prepared with K3 rotary system up to #45/0.02 instrument, irrigating with distilled water between files. The specimens were randomly assigned to three groups-final irrigation (distilled water, 1% NaOCl, and 17% EDTAC) and four subgroups (n = 8)-laser parameters (non-irradiated, 2 W/20 Hz, 3 W/20 Hz, and 4 W/20 Hz). During irradiation, the temperatures were measured on the outer root dentin wall in the three thirds, and root apex. Canals were filled with lateral condensation of AHPlus sealer and gutta-percha cones. Two slices from each third were submitted to a push-out test in Instron machine and the failure mode was analyzed. One slice from each third was analyzed by confocal laser microscopy to evaluate the percentage of the perimeter of the root canal cross-section with sealer tags and depth of tags. Data were analyzed by ANOVA, Kruskal-Wallis, and Tukey's tests (P < 0.05). Er,Cr:YSGG laser irradiation increased sealer bond strength to dentin, regardless of the final irrigation. The highest values were obtained for 3 W (4.02 ± 1.32) and 4 W (4.18 ± 0.98) powers and different from the non-irradiated group (2.64 ± 0.58) (P < 0.05). The 2 W irradiation produced similar results to 3 W and 4 W when associated with 17% EDTA. Final irrigation with 17% EDTAC provided higher bond strength (4.01 ± 1.02) compared with distilled water (3.11 ± 1.09) and 1% NaOCl (3.47 ± 1.18) (P < 0.05). The cervical third (4.01 ± 1.21) presented significantly higher bond strength than the apical third (3.04 ± 0.89). There was a greater percentage of adhesive and mixed failure. In the groups irradiated with 3 W [21.1 (14.1-27.7)] and 4 W [17.8 (11.9-23.7)], a greater depth of filling material tags was observed compared with the non-irradiated group [12.9 (9.0-20.0)]. The greatest percentage of canal perimeter with sealer tags was observed in the irradiated groups, with no difference among them (P > 0.05). The temperature rise was proportional to the increase of laser power. Er,Cr:YSGG laser irradiation increased the bond strength of an epoxy resin-based sealer to root dentin, with greater formation of sealer tags for all tested powers, especially when combined with 17% EDTAC final irrigation; temperature rise during irradiation remained below the critical threshold biologically accepted. Lasers Surg. Med. 48:985-994, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Influence of different final irrigation regimens and various endodontic filling materials on vertical root fracture resistance.

PubMed

Sungur, D D; Altundasar, E; Uzunoglu, E; Yilmaz, Z

2016-01-01

The aim of this study was to evaluate the influence of different endodontic materials and final irrigation regimens on vertical root fracture (VRF) resistance. Eighty human teeth were prepared then assigned into two groups (n = 40) according to the final irrigations. G1: 5 mL, 5.25% sodium hypochlorite (NaOCl), G2: 5 mL, 2% chlorhexidine gluconate (CHX). Each group was assigned into four subgroups according to the obturation system used (n = 10): A: iRoot SP/single gutta-percha cone (SGP), B: Only iRoot SP, C: Mineral trioxide aggregate (MTA)-Fillapex/SGP, D: AH26/SGP. The specimens were embedded in acrylic molds and subjected to compressive loading at a rate of 1 mm min until VRF occurred. Data were analyzed via three-way ANOVA tests. The statistically significant difference was found among groups (P < 0.05). The G1A and G1B and G1D revealed significantly higher-VRF values than G1C (P = 0.023). The roots filled with MTA-Fillapex revealed lower-VRF values than the other subgroups (P < 0.05). Groups irrigated with NaOCl had significantly lower-VRF values than the groups irrigated with CHX (P < 0.05). Final irrigation regimens could alter VRF resistance of root canals filled with different obturation technique and root canal sealers.

The Effect of Final Rinse Agitation with Ultrasonic or 808 nm Diode Laser on Coronal Microleakage of Root-canal Treated Teeth.

PubMed

Ramazani, Mohsen; Asnaashari, Mohammad; Ahmadi, Roghayyeh; Zarenejad, Nafiseh; Rafie, Alireza; Yazadani Charati, Jamshid

2018-01-01

This in vitro study aimed at comparing the effect of agitating the final irrigant solutions of root canal by ultrasonic or using 808 nm Diode laser on the apical seal of canal. A total of 90 extracted human maxillary central incisors were prepared up to size #45 and were randomly assigned to 4 experimental groups ( n =20) and two control groups ( n =5) respectively, as follows: I ): 3 mL of 5.25% NaOCl was agitated as final irrigant solution with ultrasonic for 30 sec. The ultrasonic tip was 1 mm shorter than the working length, II ): 3 mL of 5.25% NaOCl was agitated as final irrigant with 808 nm Diode laser for 30 sec. Fiber tip, placed in 1 mm shorter from working length was spirally moved coronally, III ): 3 mL of 17% EDTA was agitated as final irrigant with 808 nm Diode laser for 30 sec and was applied similar to group II, IV ): 3 mL of 17% EDTA was stimulated as final irrigant with ultrasonic for 30 sec and was applied similar to I. Apical seal was assessed by Dual Chamber technique using Bovine Serum Albumin protein. Kruskal-Wallis and Mann Whitney tests were used with significance level lower than 0.05% for statistical analysis. The average leakage in the negative control, positive control, and groups I, II, III, IV were: 0.00, 13.5±5.1, 1.72±2.9, 5.12±5.6, 3.36±3.7, 2.4±4.2, respectively. Statistical analysis showed significant difference between groups ( P <0.05). There was a significant difference between groups 1 and 2 in terms of protein leakage . Agitating 5.25% sodium hypochlorite solution as the final irrigant with ultrasonic is more effective in apical leakage reduction compared to other groups.

Nutrition and irrigation regime affect size and early growth of white oak seedlings

Treesearch

Paul P. Kormanik; Shi-Jean S. Sung; Taryn L. Kormanik; Thomas Tibbs; Stanley J. Zarnoch

2003-01-01

Modifications of our nursery protocol for oaks during 1997 and 1998 by instituting dormant season irrigation resulted in high white oak seedling quality. The improved growth was associated with the consistent presence of succulent fibrous roots on the upper 10 to 15 cm of taproots. Many of these fibrous roots on 1-1 stock were as sturdy as many of the permanent first-...

Apical Extrusion of Irrigants in Immature Permanent Teeth by Using EndoVac and Needle Irrigation: An In Vitro Study

PubMed Central

Velmurugan, N; Sooriaprakas, C; Jain, Preetham

2014-01-01

Objective: Immature teeth have a large apical opening and thin divergent or parallel dentinal walls; hence, with conventional needle irrigation there is a very high possibility of extrusion. This study was done to compare the apical extrusion of NaOCl in an immature root delivered using EndoVac and needle irrigation. Materials and Methods: Eighty freshly extracted maxillary central incisors were decoronated followed by access cavity preparation. Modified organotypic protocol was performed to create an open apex; then, the samples were divided into four groups (n=20): EndoVac Microcannula (group I), EndoVac Macrocannula (group II), NaviTip irrigation needle (group III) and Max-i-Probe Irrigating needle (group IV); 9.0 ml of 3% sodium hypochlorite was delivered slowly over a period of 60 seconds. Extruded irrigants were collected in a vial and analysed statistically. Results: Group I, group III and group IV showed 100% extrusion (20/20) but group II showed only 40% extrusion (8/20). The difference in this respect between group II and other groups was statistically significant (P<0.001). With regards to the volume of extrusion, group II had only 0.23 ml of extruded irrigant. Group I extruded 7.53ml of the irrigant. Group III and group IV extruded the entire volume of irrigant delivered. Conclusion: EndoVac Macrocannula resulted in the least extrusion of irrigant in immature teeth when compared to EndoVac Microcannula and conventional needle irrigation. PMID:25584055

Irrigated areas of India derived using MODIS 500 m time series for the years 2001-2003

USGS Publications Warehouse

Dheeravath, V.; Thenkabail, P.S.; Chandrakantha, G.; Noojipady, P.; Reddy, G.P.O.; Biradar, C.M.; Gumma, M.K.; Velpuri, M.

2010-01-01

The overarching goal of this research was to develop methods and protocols for mapping irrigated areas using a Moderate Resolution Imaging Spectroradiometer (MODIS) 500 m time series, to generate irrigated area statistics, and to compare these with ground- and census-based statistics. The primary mega-file data-cube (MFDC), comparable to a hyper-spectral data cube, used in this study consisted of 952 bands of data in a single file that were derived from MODIS 500 m, 7-band reflectance data acquired every 8-days during 2001-2003. The methods consisted of (a) segmenting the 952-band MFDC based not only on elevation-precipitation-temperature zones but on major and minor irrigated command area boundaries obtained from India's Central Board of Irrigation and Power (CBIP), (b) developing a large ideal spectral data bank (ISDB) of irrigated areas for India, (c) adopting quantitative spectral matching techniques (SMTs) such as the spectral correlation similarity (SCS) R2-value, (d) establishing a comprehensive set of protocols for class identification and labeling, and (e) comparing the results with the National Census data of India and field-plot data gathered during this project for determining accuracies, uncertainties and errors. The study produced irrigated area maps and statistics of India at the national and the subnational (e.g., state, district) levels based on MODIS data from 2001-2003. The Total Area Available for Irrigation (TAAI) and Annualized Irrigated Areas (AIAs) were 113 and 147 million hectares (MHa), respectively. The TAAI does not consider the intensity of irrigation, and its nearest equivalent is the net irrigated areas in the Indian National Statistics. The AIA considers intensity of irrigation and is the equivalent of "irrigated potential utilized (IPU)" reported by India's Ministry of Water Resources (MoWR). The field-plot data collected during this project showed that the accuracy of TAAI classes was 88% with a 12% error of omission and 32% of error of commission. Comparisons between the AIA and IPU produced an R2-value of 0.84. However, AIA was consistently higher than IPU. The causes for differences were both in traditional approaches and remote sensing. The causes of uncertainties unique to traditional approaches were (a) inadequate accounting of minor irrigation (groundwater, small reservoirs and tanks), (b) unwillingness to share irrigated area statistics by the individual Indian states because of their stakes, (c) absence of comprehensive statistical analyses of reported data, and (d) subjectivity involved in observation-based data collection process. The causes of uncertainties unique to remote sensing approaches were (a) irrigated area fraction estimate and related sub-pixel area computations and (b) resolution of the imagery. The causes of uncertainties common in both traditional and remote sensing approaches were definitions and methodological issues. ?? 2009 International Society for Photogrammetry and Remote Sensing, Inc. (ISPRS).

76 FR 33361 - Notice of Availability of the Final Environmental Impact Statement for the Madera Irrigation...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-06-08

... Impact Statement for the Madera Irrigation District Water Supply Enhancement Project located in Madera... Madera Irrigation District Water Supply Enhancement Project (MID WSEP). Reclamation proposes to approve... supply reliability and flexibility for current and future water demand, and reduce local overdraft, MID...

Release of Growth Factors into Root Canal by Irrigations in Regenerative Endodontics.

PubMed

Zeng, Qian; Nguyen, Sean; Zhang, Hongming; Chebrolu, Hari Priya; Alzebdeh, Dalia; Badi, Mustafa A; Kim, Jong Ryul; Ling, Junqi; Yang, Maobin

2016-12-01

The aim of this study was to investigate the release of growth factors into root canal space after the irrigation procedure of regenerative endodontic procedure. Sixty standardized root segments were prepared from extracted single-root teeth. Nail varnish was applied to all surfaces except the root canal surface. Root segments were irrigated with 1.5% NaOCl + 17% EDTA, 2.5% NaOCl + 17% EDTA, 17% EDTA, or deionized water. The profile of growth factors that were released after irrigation was studied by growth factor array. Enzyme-linked immunosorbent assay was used to validate the release of transforming growth factor (TGF)-β1 and basic fibroblast growth factor (bFGF) at 4 hours, 1 day, and 3 days after irrigation. The final concentrations were calculated on the basis of the root canal volume measured by cone-beam computed tomography. Dental pulp stem cell migration on growth factors released from root segments was measured by using Transwell assay. Total of 11 of 41 growth factors were detected by growth factors array. Enzyme-linked immunosorbent assay showed that TGF-β1 was released in all irrigation groups. Compared with the group with 17% EDTA (6.92 ± 4.49 ng/mL), the groups with 1.5% NaOCl + 17% EDTA and 2.5% NaOCl + 17% EDTA had significantly higher release of TGF-β1 (69.04 ± 30.41 ng/mL and 59.26 ± 3.37 ng/mL, respectively), with a peak release at day 1. The release of bFGF was detected at a low level in all groups (0 ng/mL to 0.43 ± 0.22 ng/mL). Migration assay showed the growth factors released from root segments induced dental pulp stem cell migration. The root segment model in present study simulated clinical scenario and indicated that the current irrigation protocol released a significant amount of TGF-β1 but not bFGF. The growth factors released into root canal space induced dental pulp stem cell migration. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Influence of immediate post-extraction socket irrigation on development of alveolar osteitis after mandibular third molar removal: a prospective split-mouth study, preliminary report.

PubMed

Tolstunov, L

2012-12-01

The aim of this prospective comparative split-mouth study was to evaluate the role of socket irrigation with a normal saline solution routinely used at the end of extraction on the development of alveolar osteitis (AO) after removal of impacted mandibular third molars (MTMs). Thirty-five patients who satisfied the inclusion criteria were involved in the study and underwent extraction of four third-molars. To be included in the study, the mandibular third molars had to be impacted (partial or full bone) and require an osteotomy for extraction with use of a motorised drill. All surgeries were done under local anaesthesia or IV sedation. This was a prospective split-mouth study. The patient's left (assistant) side was a control side; it had a standard extraction technique of an impacted mandibular third molar that required a buccal full-thickness flap, buccal trough (osteotomy) and extraction of the tooth (with or without splitting the tooth into segments), followed by a traditional end-of-surgery debridement protocol consisting of a gentle curettage, bone filing of the socket walls, socket irrigation with approximately 5 ml of sterile normal saline solution and socket suctioning. The patient's right (operator) side was an experimental side; it also had a standard extraction technique of an impacted mandibular third molar at the beginning with a flap and osteotomy, but it was followed by a modified end-of-surgery protocol. It consisted of gentle curettage but the socket was not irrigated and not suctioned. It was simply left to bleed. The gauze was placed on top of the socket for haemostasis on both sides and the patient was asked to bite. On both sides, the buccal flap was positioned back without the suture. All patients were seen for a follow-up appointment four to seven days after the surgery to assess healing and check for symptoms and signs of alveolar osteitis, if present, on both irrigated and non-irrigated sides. This study followed the ethical guidelines of human subjects based on the Helsinki Declaration. Thirty-five patients or 70 sockets were evaluated. Eleven out of 35 patients in the study were subjected to a dry socket syndrome (31.4%). The higher number of AO was likely related to specifics of MTM selection in this study - only impacted (partial and full bone) MTMs were chosen. Among eleven patients with AO, two patients had a bilateral condition. By excluding two patients with bilateral dry sockets from the study, there were nine patients (18 extraction sites) with unilateral AO in the study. Seven out of nine patients (14 extraction sites) developed unilateral dry socket on the control (irrigated) side (77.8%) and only two (four extraction sites) on the experimental (non-irrigated) side (22.2%). Therefore, in this study there were 3.5 times more patients (extraction sites) with dry socket syndrome on the irrigated (control) side than patients (extraction sites) in the non-irrigated (experimental) side. A noticeable difference of dry socket syndromes (77.8% on the irrigated versus 22.2% on non-irrigated side) was demonstrated between the traditional extraction protocol versus modified approach without the end-of-surgery irrigation. The study demonstrated that the post-extraction socket bleeding is very important for the proper uncomplicated socket healing. If it's not washed away with irrigation solution at the end of extraction, the normal blood clot has a higher likelihood to form, and therefore, can potentially lead to an uncomplicated socket healing without development of alveolar osteitis. Socket bleeding at the extraction site creates a favourable environment for the formation of a blood clot - a protective dressing - necessary for a favourable osseous healing of the socket.

Incidence of bacterial diseases associated with irrigation methods on onions (Allium cepa).

PubMed

Chorolque, A; Pozzo Ardizzi, C; Pellejero, G; Aschkar, G; García Navarro, F J; Jiménez Ballesta, R

2018-04-24

In the last decade, diseases of bacterial origin in onions have increased and this has led to significant losses in production. These diseases are currently observed in both the Old and New Worlds. The aim of the experimental work reported here was to evaluate whether the irrigation method influences the incidence of diseases of bacterial origin. In cases where the inoculum was natural, the initial incidence of Soft Bacterial Rot was not manifested in any treatment in the first year, whereas at the end of the conservation period all treatments had increased incidences of infection. Sprinkler irrigation (8%) was statistically differentiated from the other treatments, for which the final incidence was similar (4.5%). For all irrigation treatments, the final incidence of Bacterial Soft Rot decreased or remained stable towards the end of the cycle, with the exception of sprinkler irrigation in 2015, which increased. It can be inferred from the results that the irrigation method does have an influence on the incidence of diseases of bacterial origin in the post-harvest stage for onions. This article is protected by copyright. All rights reserved.

Low-volume versus high-volume initiated trans-anal irrigation therapy in adults with chronic constipation: study protocol for a randomised controlled trial.

PubMed

Emmett, Christopher; Close, Helen; Mason, James; Taheri, Shiva; Stevens, Natasha; Eldridge, Sandra; Norton, Christine; Knowles, Charles; Yiannakou, Yan

2017-03-31

Constipation is common in adults and up to 20% of the population report this symptom. Chronic constipation (CC), usually defined as more than 6 months of symptoms, is less common but results in 0.5 million UK GP consultations per annum. The effect of symptoms on measured quality of life (QOL) is significant, and CC consumes significant health care resources. In the UK, it is estimated that 10% of district nursing time is spent on constipation. Trans-anal irrigation therapy has become a widely used treatment despite a lack of robust efficacy data to support its use. The long-term outcome of treatment is also unclear. A randomised comparison of two different methods of irrigation (high- and low-volume) will provide valuable evidence of superiority of one system over the other, as well as providing efficacy data for the treatment as a whole. Participants will be recruited based on predetermined eligibility criteria. Following informed consent, they will be randomised to either high-volume (HV) or low-volume (LV) irrigation and undergo standardised radiological and physiological investigations. Following training, they will commence home irrigation with the allocated device. Data will be collected at 1, 3, 6 and 12 months according to a standardised outcomes framework. The primary outcome is PAC-QOL, measured at 3 months. The study is powered to detect a 10% difference in outcome between systems at 3 months; this means that 300 patients will need to be recruited. This study will be the first randomised comparison of two different methods of trans-anal irrigation. It will also be the largest prospective study of CC patients treated with irrigation. It will provide evidence for the effectiveness of irrigation in the treatment of CC, as well as the comparative effectiveness of the two methods. This will enable more cost-effective and evidence-based use of irrigation. Also, the results will be combined with the other studies in the CapaCiTY programme to generate an evidence-based treatment algorithm for CC in adults. ISRCTN, identifier: ISRCTN11093872 . Registered on 11 November 2015. Trial not retrospectively registered. Protocol version 3 (22 January 2016).

Crowdsourcing Science to Promote Human Health: New Tools to Promote Sampling of Mosquito Populations by Citizen Scientists

NASA Astrophysics Data System (ADS)

Boger, R. A.; Low, R.; Jaroensutasinee, M.; Jaroensutasinee, K.; Sparrow, E. B.; Costosa, J. I.; Medina, J.; Randolph, G.

2015-12-01

GLOBE in Thailand and GLOBE in Africa independently developed citizen science protocols for collecting and analyzing mosquito larvae. These protocols have been piloted in several workshops and implemented in schools. Data collected have been used for several secondary, undergraduate and graduate student research studies. Over this past year, 2015, these protocols have been synthesized into one protocol that will be made available to the world-wide community through the GLOBE website (www.globe.gov). This new protocol is designed to be flexible in the mosquito species that can be collected and the types of environments sampled (e.g., containers in and around the house, ponds, irrigation ditches in a rice paddy field). Plans are underway to enable web-based data entry and mobile apps for data collection and submission. Once everything is finalized, a GLOBE field campaign will be initiated for citizen scientists to collect meaningful data on where different types of mosquito larvae are found and how the abundance and distribution is changing seasonally. To assist in the standardization of data collection and quality control, training slides are being developed and will be made available in early 2016. This will enable a wider participation of citizen scientists to participate in this effort to collect mosquito data by making it easier to become part of the GLOBE community. As with mosquito larvae, training slides are being created for hydrosphere, biosphere, atmosphere, and pedosphere GLOBE measurement protocols. The development of the mosquito protocol and the training slides are in direct response to the GLOBE community's desire to increase citizen science participation beyond primary and secondary schools, in observing and measuring environmental change.

WaterSense Specification for Weather-Based Irrigation Controllers Supporting Statement

EPA Pesticide Factsheets

The release of this final specification is the result of more than four years of collaboration between EPA and controller manufacturers, water utilities, irrigation industry representatives, and other stakeholders.

The role of remotely sensed and other special data for predictive modeling: the Umatilla, Oregon example

USGS Publications Warehouse

Loveland, Thomas R.; Johnson, Gary E.

1983-01-01

Landsat data and 1:24 000-scale aerial photographs were initially used to map the expansion of irrigation from 1973 to 1979 and to identify crops under irrigation in 1979. The crop data were then used with historical water requirement figures and digital topographic and hydrographic data to estimate water and power use for the 1979 irrigation season. The final project task involved production of a composite map of land suitability for irrigation development based on land cover (from Landsat), landownership, soil irrigability, slope gradient, and potential energy costs.

In vivo efficacy of three different endodontic irrigation systems for irrigant delivery to working length of mesial canals of mandibular molars.

PubMed

Munoz, Hugo Roberto; Camacho-Cuadra, Karla

2012-04-01

Many in vitro studies have debated over the ability of different irrigant delivery and/or agitation systems to reach the apical third of curved root canals; however, little is known about irrigant penetration in vivo. Therefore, the purpose of this study was to compare the efficacy of the conventional endodontic irrigation needle, passive ultrasonic irrigation (PUI), and a negative pressure system for irrigant delivery to working length (WL) of mesial canals of mandibular molars. Thirty mesial canals of 30 vital mandibular first or second molars were randomly assigned into 3 groups (n = 10): (1) Monoject syringe with 27-gauge needle; (2) PUI with IrriSafe tip; and (3) EndoVac system. All canals were treated following the same preparation protocol to size 35/0.04 by using 5.25% NaOCl as irrigant during preparation procedure. Before obturation, canals were irrigated with 1 mL of a radiopaque solution by using the assigned irrigation system, and a digital radiograph was taken by using a parallel technique. With the aid of image editing software the distance between WL and maximum irrigant penetration was measured. Mean distances for Monoject, PUI, and EndoVac groups were 1.51 mm, 0.21 mm, and 0.42 mm, respectively. Analysis of variance test showed statistically significant differences between groups (P < .001). Tukey honestly significant difference test showed statistically significant differences between the Monoject group and the other 2 groups (P < .001) but no significant differences between PUI and EndoVac groups (P = .06). PUI and EndoVac are more effective than the conventional endodontic needle in delivering irrigant to WL of root canals. Copyright © 2012 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

The effect of different final irrigant activation techniques on the bond strength of an epoxy resin-based endodontic sealer: a preliminary study.

PubMed

Topçuoğlu, Hüseyin Sinan; Tuncay, Öznur; Demirbuga, Sezer; Dinçer, Asiye Nur; Arslan, Hakan

2014-06-01

The aim of this study was to evaluate whether or not different final irrigation activation techniques affect the bond strength of an epoxy resin-based endodontic sealer (AH Plus; Dentsply DeTrey, Konstanz, Germany) to the root canal walls of different root thirds. Eighty single-rooted human mandibular premolars were prepared by using the ProTaper system (Dentsply Maillefer, Ballaigues, Switzerland) to size F4, and a final irrigation regimen using 3% sodium hypochlorite and 17% EDTA was performed. The specimens were randomly divided into 4 groups (n = 20) according to the final irrigation activation technique used as follows: no activation (control), manual dynamic activation (MDA), CanalBrush (Coltene Whaledent, Altststten, Switzerland) activation, and ultrasonic activation. Five specimens from each group were prepared for scanning electron microscopic observation to assess the smear layer removal after the final irrigation procedures. All remaining roots were then obturated with gutta-percha and AH Plus sealer. A push-out test was used to measure the bond strength between the root canal dentin and AH Plus sealer. The data obtained from the push-out test were analyzed using 2-way analysis of variance and Tukey post hoc tests. The bond strength values mostly decreased in the coronoapical direction (P < .001). In the coronal and middle thirds, ultrasonic activiation showed a higher bond strength than other groups (P < .05). In the apical third, MDA displayed the highest bond strength to root dentin (P < .05). The majority of specimens exhibited cohesive failures. The bond strength of AH Plus sealer to root canal dentin may improve with ultrasonic activation in the coronal and middle thirds and MDA in the apical third. Copyright © 2014 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Effects of different sonic activation protocols on debridement efficacy in teeth with single-rooted canals

PubMed Central

Niu, Li-na; Luo, Xiao-juan; Li, Guo-hua; Bortoluzzi, Eduardo A.; Mao, Jing; Chen, Ji-hua; Gutmann, James L.; Pashley, David H.; Tay, Franklin R.

2014-01-01

Objectives The effects of different EndoActivator® (EA) sonic activation protocols on root canal debridement efficacy were examined. Methods Root canals in 48 single-rooted teeth were instrumented, irrigated initially with NaOCl and divided into 6 groups (N=8) based on the application time of QMix (antimicrobial calcium-chelating irrigant), and the time and sequence of EA irrigant activation - Positive Control: 90 sec QMix; Negative Control: 90 sec saline; Group 1A: 15 sec QMix + 15 sec QMix with EA-activation; Group 1B: 30 sec QMix + 30 sec of QMix with EA-activation; Group 2A: 15 sec QMix with EA-activation + 15 sec QMix; Group 2B: 30 sec QMix with EA-activation + 30 sec QMix. Split roots were examined with scanning electron microscopy for assignment of smear and debris scores in locations along the coronal, middle and apical thirds of the canals. The overall cleanliness of pooled canal locations in the Positive Control and the 4 experimental groups were compared with chi-square tests. Results Significant differences were detected among the 5 groups (p<0.001). Post-hoc pairwise comparisons indicated that the overall canal cleanliness was in the order (from best to worst): 1B = 2B > 2A > 1A > Positive Control. Completely clean canals could not be achieved due to the absence of continuous irrigant flow for EA to clear intraradicular debris. Conclusions Irrespective of the sonic activation sequence, irrigant activation for 30 seconds during a 60-second period of QMix application appears to maximize the smear layer and debris removal potential of the EndoActivator® system. PMID:24878251

Factors affecting irrigant extrusion during root canal irrigation: a systematic review.

PubMed

Boutsioukis, C; Psimma, Z; van der Sluis, L W M

2013-07-01

The aim of the present study was to conduct a systematic review and critical analysis of published data on irrigant extrusion to identify factors causing, affecting or predisposing to irrigant extrusion during root canal irrigation of human mature permanent teeth. An electronic search was conducted in Cochrane Library, LILACS, PubMed, SciELO, Scopus and Web of Knowledge using a combination of the terms 'irrigant', 'rinse', 'extrusion', 'injection', 'complication', 'accident', 'iatrogenic', 'root canal', 'tooth' and 'endodontic'. Additional studies were identified by hand-searching of six endodontic journals and the relevant chapters of four endodontic textbooks, resulting in a total of 460 titles. No language restriction was imposed. After applying screening and strict eligibility criteria by two independent reviewers, 40 case reports and 10 ex vivo studies were included in the review. A lack of clinical studies focusing on irrigant extrusion during root canal irrigation was evident. The reviewed case reports focused mainly on the clinical manifestations and management of the accidents and did not provide adequate details on the possible factors that may influence irrigant extrusion. The data from the included ex vivo studies were inconclusive due to major methodological limitations, such as not simulating the presence of periapical tissues and not assessing the validity of irrigant detection methods. The extensive variability in the protocols employed hindered quantitative synthesis. The choice of factors investigated in ex vivo studies seems not to have been driven by the available clinical evidence. These issues need to be addressed in future studies. © 2012 International Endodontic Journal. Published by John Wiley & Sons Ltd.

Canal and isthmus debridement efficacies of two irrigant agitation techniques in a closed system

PubMed Central

Susin, L.; Yoon, J. C.; Liu, Y.; Parente, J. M.; Loushine, R. J.; Ricucci, D.; Bryan, T.; Weller, R. N.; Pashley, D. H.; Tay, F. R.

2010-01-01

Aim To compare canal and isthmus debris debridement efficacies of the manual dynamic irrigation (MDI) and apical negative pressure (ANP) techniques in the mesial root of mandibular first molars with narrow isthmi, using a closed canal design. Methodology Micro-computed tomography was employed to select 20 teeth, each containing a narrow isthmus. Each root was sealed at the apex with hot glue and embedded in polyvinylsiloxane to simulate a closed canal system. The teeth were submitted to a standardised instrumentation protocol. Final irrigation was performed with either the MDI or the ANP technique using the EndoVac system (N=10). Masson trichrome-stained sections were prepared from completely demineralised roots at ten canal levels between 1–2.8 mm of the anatomical apices. Areas occupied by canals and isthmus of each root and debris in the corresponding regions were digitised by the NIH Image J software and statistically analysed using two-way repeated measures ANOVA. Results For the instrumented canals, there were no differences between the two groups (p=0.131) in the area occupied by debris at all canal levels (p=0.343). Conversely, for the isthmus, less debris was found in the ANP group (p<0.001) but no differences were seen in each group with respect to the ten canal levels (p=0.352). Conclusion Neither technique produce completely removed debris from the isthmus regions. However the EndoVac system, which encompasses the ANP concept, removed considerably more debris from narrow isthmi of the mandibular mesial roots. PMID:20726910

The effect of peracetic acid on removing calcium hydroxide from the root canals.

PubMed

Sağsen, Burak; Ustün, Yakup; Aslan, Tuğrul; Canakçi, Burhan Can

2012-09-01

The goal of this study was to evaluate the efficiencies of different irrigation solutions in the removal of calcium hydroxide (CH). Forty-eight maxillary central incisor teeth were used. Root canals were prepared with the ProTaper system (Dentsply Maillefer, Baillagues, Switzerland). Five milliliters 2% NaOCl, 5 mL 17% EDTA, and 10 mL saline were used for final irrigation. The canals were filled with CH paste. Specimens were randomly divided into 4 experimental groups (n = 10) according to irrigation protocols. Positive and negative control groups (n = 4) were used. Group 1 used 2.5 mL 17% EDTA, group 2 used 2.5 mL 2.5% NaOCl + 2.5 mL 17% EDTA, group 3 used 2.5 mL 1% peracetic acid (PAA), and group 4 used 2.5 mL 0.5% PAA. The specimens were evaluated with scanning electron microscope analysis and scored. Kruskal-Wallis and Student Newman-Keuls post hoc tests were used for statistical analysis. In the apical thirds, 1% PAA was superior to the other groups (P < .05); however, there were no significant differences among the other groups (P > .05). In the middle thirds, no significant differences were found among the groups (P > .05). In the coronal thirds, 1% PAA was superior to the other groups. There were significant differences among all the other groups (P < .05). According to the findings of the present study, 1% PAA could be recommended for the removal of CH from the root canals. Crown Copyright © 2012. Published by Elsevier Inc. All rights reserved.

Irrigant flow within a prepared root canal using various flow rates: a Computational Fluid Dynamics study.

PubMed

Boutsioukis, C; Lambrianidis, T; Kastrinakis, E

2009-02-01

To study using computer simulation the effect of irrigant flow rate on the flow pattern within a prepared root canal, during final irrigation with a syringe and needle. Geometrical characteristics of a side-vented endodontic needle and clinically realistic flow rate values were obtained from previous and preliminary studies. A Computational Fluid Dynamics (CFD) model was created using FLUENT 6.2 software. Calculations were carried out for five selected flow rates (0.02-0.79 mL sec(-1)) and velocity and turbulence quantities along the domain were evaluated. Irrigant replacement was limited to 1-1.5 mm apical to the needle tip for all flow rates tested. Low-Reynolds number turbulent flow was detected near the needle outlet. Irrigant flow rate affected significantly the flow pattern within the root canal. Irrigation needles should be placed to within 1 mm from working length to ensure fluid exchange. Turbulent flow of irrigant leads to more efficient irrigant replacement. CFD represents a powerful tool for the study of irrigation.

The efficiency of different irrigation solutions and techniques for the removal of triple antibiotic paste from simulated immature root canals.

PubMed

Ustun, Y; Düzgün, S; Aslan, T; Aktı, A

2018-03-01

The purpose of this study was to evaluate the efficiencies of different irrigation protocols in the removal of triple antibiotic paste (TAP) from root canals. A total of 127 extracted human maxillary incisor teeth were prepared. Then, root-end resection of 3 mm was accomplished to simulate immature apex model. The root canals were filled with TAP, after 21 days, randomly divided into nine groups according to irrigation systems and solutions (n = 13). Conventional irrigation (CI) groups - Group 1: Root canal irrigation was performed with CI by Peracetic acid (PAA) solution, Group 2: Root canal irrigation was performed with CI by etidronic acid 1-hydroxyethylidene-1, 1-bisphosphonate (HEBP) + sodium hypochlorite (NaOCl) solution, Group 3: Root canal irrigation was performed with CI by ethylenediaminetetraacetic acid (EDTA)/NaOCl solutions. Vibringe system groups - Group 4: Root canal irrigation was performed with Vibringe system by PAA solution, Group 5: Root canal irrigation was performed with Vibringe system by HEBP + NaOCl solution, Group 6: Root canal irrigation was performed with Vibringe system by EDTA/NaOCl solution. EndoVac system groups - Group 7: Root canal irrigation was performed with EndoVac system by PAA solution, Group 8: Root canal irrigation was performed with EndoVac system by HEBP + NaOCl solution, Group 9: Root canal irrigation was performed with EndoVac system by EDTA/NaOCl solution. Control Group: (n = 0). Samples were sectioned vertically, and the amount of remaining medicament was scored for each root half and data were statistically analyzed. Among the irrigation systems, CI groups showed the highest scores at both apical and coronal parts (P < 0.05). In comparisons among the solutions, at the apical part, PAA groups showed the highest scores (P < 0.05). At the coronal part, EDTA + NaOCl groups showed the lowest score values (P < 0.05). The use of irrigation systems improved the removal of TAP from the simulated immature root canals. Also, as an irrigation solution EDTA gives more promising results than PAA and HEBP solutions.

Impact of the reusing of food manufacturing wastewater for irrigation in a closed system on the microbiological quality of the food crops.

PubMed

Beneduce, Luciano; Gatta, Giuseppe; Bevilacqua, Antonio; Libutti, Angela; Tarantino, Emanuele; Bellucci, Micol; Troiano, Eleonora; Spano, Giuseppe

2017-11-02

In order to evaluate if the reuse of food industry treated wastewater is compatible for irrigation of food crops, without increased health risk, in the present study a cropping system, in which ground water and treated wastewater were used for irrigation of tomato and broccoli, during consecutive crop seasons was monitored. Water, crop environment and final products were monitored for microbial indicators and pathogenic bacteria, by conventional and molecular methods. The microbial quality of the irrigation waters influenced sporadically the presence of microbial indicators in soil. No water sample was found positive for pathogenic bacteria, independently from the source. Salmonella spp. and Listeria monocytogenes were detected in soil samples, independently from the irrigation water source. No pathogen was found to contaminate tomato plants, while Listeria monocytogenes and E. coli O157:H7 were detected on broccoli plant, but when final produce were harvested, no pathogen was detected on edible part. The level of microbial indicators and detection of pathogenic bacteria in field and plant was not dependent upon wastewater used. Our results, suggest that reuse of food industry wastewater for irrigation of agricultural crop can be applied without significant increase of potential health risk related to microbial quality. Copyright © 2017 Elsevier B.V. All rights reserved.

Laser assisted irrigation and hand irrigation for root canal decontamination: a comparison

NASA Astrophysics Data System (ADS)

Olivi, M.; Stefanucci, M.; Todea, C.

2014-01-01

Aim: to compare the bactericidal efficiency of conventional method and LAI for root canal decontamination. Material and method: 22 human single root teeth, extracted for periodontal problems, mechanically prepared up to ISO 25 at the working lenght were divided in 2 groups: after sterilization, the teeth were infected with enterococcus faecalis and incubated for 4 weeks. Group A: 10 teeth were irrigated with conventional hand technique (CI): 3ml of 5% NaClO were used for two times of 30s each and after washing with sterile bi-distilled water for 20s, a final irrigation was performed with 3ml of 17% EDTA. Group B: 10 teeth were irrigated with 3ml of NaClO and activated by erbium laser, two cycles of 30s; also the final irrigation with 3ml of 17% EDTA was activated by erbium laser. In both the groups a resting time of 30s was used between the two sessions to allow the reaction rate of NaClO. The Erbium laser 2940 nm (LightWalker AT, Fotona; Lublijana, Slovenia) was used with 50microsecond pulse duration, at 15Hz, 20mJ, with a 600micron PIPS tip. Two samples were used as positive and negative control.

Documentation of methods and inventory of irrigation data collected for the 2000 and 2005 U.S. Geological Survey Estimated use of water in the United States, comparison of USGS-compiled irrigation data to other sources, and recommendations for future compilations

USGS Publications Warehouse

Dickens, Jade M.; Forbes, Brandon T.; Cobean, Dylan S.; Tadayon, Saeid

2011-01-01

An indirect method for estimating irrigation withdrawals is presented and results are compared to the 2005 USGS-reported irrigation withdrawals for selected States. This method is meant to demonstrate a way to check data reported or received from a third party, if metered data are unavailable. Of the 11 States where this method was applied, 8 States had estimated irrigation withdrawals that were within 15 percent of what was reported in the 2005 water-use compilation, and 3 States had estimated irrigation withdrawals that were more than 20 percent of what was reported in 2005. Recommendations for improving estimates of irrigated acreage and irrigation withdrawals also are presented in this report. Conveyance losses and irrigation-system efficiencies should be considered in order to achieve a more accurate representation of irrigation withdrawals. Better documentation of data sources and methods used can help lead to more consistent information in future irrigation water-use compilations. Finally, a summary of data sources and methods used to estimate irrigated acreage and irrigation withdrawals for the 2000 and 2005 compilations for each WSC is presented in appendix 1.

Policy support, economic incentives and the adoption of irrigation technology in China

NASA Astrophysics Data System (ADS)

Cremades, R.; Wang, J.; Morris, J.

2014-11-01

The challenges China faces in terms of water availability in the agricultural sector are exacerbated by the sector's low irrigation efficiency. To increase irrigation efficiency, promoting irrigation technology has been emphasized by policy makers in China. The overall goal of this paper is to understand the effect of policy support and economic incentives on the adoption of irrigation technology in China. Based on a unique dataset collected at household and village levels from seven provinces in China, results indicated that household-based irrigation technology has become noticeable in almost every Chinese village. In contrast, only about half of Chinese villages have adopted community-based irrigation technology. Despite the relatively high adoption level of household-based irrigation technology at the village level, its actual adoption on crop-sown areas was not high, and it was even lower for community-based irrigation technology. The econometric analyses results revealed that policy supports via subsidies and extension services have played an important role in promoting the adoption of irrigation technology. Strikingly, the present irrigation pricing policy has played significant but contradictory roles in promoting the adoption of different types of irrigation technology. Irrigation pricing showed a positive impact on household-based irrigation technology, and a negative impact on community-based irrigation technology, possibly related to their substitution relationship, because having higher adoption of household-based irrigation technology reduce the incentives to invest in community-based irrigation technology. The paper finally concludes and discusses some policy implications.

Is There Still a Role for Irrigation and Debridement With Liner Exchange in Acute Periprosthetic Total Knee Infection?

PubMed

Duque, Andrés F; Post, Zachary D; Lutz, Rex W; Orozco, Fabio R; Pulido, Sergio H; Ong, Alvin C

2017-04-01

Periprosthetic joint infection (PJI) is an important cause of failure in total knee arthroplasty. Irrigation and debridement including liner exchange (I&D/L) success rates have varied for acute PJI. The purpose of this study is to present results of a specific protocol for I&D/L with retention of total knee arthroplasty components. Sixty-seven consecutive I&D/L patients were retrospectively evaluated. Inclusion criteria for I&D/L were as follows: fewer than 3 weeks of symptoms, no immunologic compromise, intact soft tissue sleeve, and well-fixed components. I&D/L consisted of extensive synovectomy; irrigation with 3 L each of betadine, Dakin's, bacitracin, and normal saline solutions; and exchange of the polyethylene component. Postoperatively, all patients were treated with intravenous antibiotics. Infection was considered eradicated if the wound healed without persistent drainage, there was no residual pain or evidence of infection. Forty-six patients (68.66%) had successful infection eradication regardless of bacterial strain. Those with methicillin-resistant Staphylococcus aureus (MRSA) had an 80% failure rate and those with Pseudomonas aeruginosa had a 66.67% failure rate. The success rate for bacteria other than MRSA and Pseudomonas was 85.25%. Our protocol for I&D/L was successful in the majority of patients who met strict criteria. We recommend that PJI patients with MRSA or P aeruginosa not undergo I&D/L and be treated with 2-stage revision. For nearly all other patients, our protocol avoids the cost and patient morbidity of a 2-stage revision. Copyright © 2016 Elsevier Inc. All rights reserved.

Policies, economic incentives and the adoption of modern irrigation technology in China

NASA Astrophysics Data System (ADS)

Cremades, R.; Wang, J.; Morris, J.

2015-07-01

The challenges China faces in terms of water availability in the agricultural sector are exacerbated by the sector's low irrigation efficiency. To increase irrigation efficiency, promoting modern irrigation technology has been emphasized by policy makers in the country. The overall goal of this paper is to understand the effect of governmental support and economic incentives on the adoption of modern irrigation technology in China, with a focus on household-based irrigation technology and community-based irrigation technology. Based on a unique data set collected at household and village levels from seven provinces, the results indicated that household-based irrigation technology has become noticeable in almost every Chinese village. In contrast, only about half of Chinese villages have adopted community-based irrigation technology. Despite the relatively high adoption level of household-based irrigation technology at the village level, its actual adoption in crop sown areas was not high, even lower for community-based irrigation technology. The econometric analysis results revealed that governmental support instruments like subsidies and extension services policies have played an important role in promoting the adoption of modern irrigation technology. Strikingly, the present irrigation pricing policy has played a significant but contradictory role in promoting the adoption of different types of modern irrigation technology. Irrigation pricing showed a positive impact on household-based irrigation technology, and a negative impact on community-based irrigation technology, possibly related to the substitution effect that is, the higher rate of adoption of household-based irrigation technology leads to lower incentives for investment in community-based irrigation technology. The paper finally concludes and discusses some policy implications.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kurnik, Charles W.; Stoughton, Kate M; Figueroa, Jorge

This measurement and verification (M&V) protocol provides procedures for energy service companies (ESCOs) and water efficiency service companies (WESCOs) to determine water savings resulting from water conservation measures (WCMs) in energy performance contracts associated with outdoor irrigation efficiency projects. The water savings are determined by comparing the baseline water use to the water use after the WCM has been implemented. This protocol outlines the basic structure of the M&V plan, and details the procedures to use to determine water savings.

Gold Standard Tests

DTIC Science & Technology

2001-06-01

important issues need to be understood. Caloric Irrigation: Irrigation of both ears with water of 30 and 44 degree Celsius is the standard Anamnesis ... anamnesis , falls short. In the usual because there are many factors which may clinical situation, a vestibular deficit is suspected if influence the final

Heat treatment induced bacterial changes in irrigation water and their implications for plant disease management.

PubMed

Hao, W; Hong, C X

2014-05-01

A new heat treatment for recycled irrigation water using 48 °C for 24 h to inactivate Phytophthora and bacterial plant pathogens is estimated to reduce fuel cost and environmental footprint by more than 50 % compared to current protocol (95 °C for 30 s). The objective of this study was to determine the impact of this new heat treatment temperature regime on bacterial community structure in water and its practical implications. Bacterial communities in irrigation water were analyzed before and after heat treatment using both culture-dependent and -independent strategies based on the 16S ribosomal DNA. A significant shift was observed in the bacterial community after heat treatment. Most importantly, bacteria with biological control potential--Bacillus and Paenibacillus, and Pseudomonas species became more abundant at both 48 and 42 °C. These findings imply that the new heat treatment procedure not only controls existing plant pathogens but also may make the heat-treated irrigation water a more antagonistic environment against plant pathogens, promoting sustainable disease management.

The effects of different irrigation protocols on removing calcium hydroxide from the root canals.

PubMed

Üstün, Y; Aslan, T; Sagsen, B; Dincer, A N

2016-01-01

The aim of this study was to evaluate the efficiencies of different irrigation protocols and solutions in the removal of calcium hydroxide (Ca[OH]2). Sixty-eight maxillary incisors were used. Root canals were prepared and filled with Ca(OH)2. Two control (n = 4) and six experimental groups (n = 10) were adjusted: Group 1:1% peracetic acid (PAA) + master apical file (MAF); Group 2: 17% ethylenediaminetetraacetic acid (EDTA) + MAF; Group 3: 9% 1-hydroxyethylidene-1,1-bisphosphonate (HEBP) + MAF; Group 4: 1% PAA + ultrasonic activation (UA); Group 5: 17% EDTA + UA; Group 6: 9% HEBP + UA. The cleanliness of root canal thirds were evaluated with scanning electron microscopy. Statistical analysis were performed (α = 0.05). At coronal thirds; PAA + UA was superior to EDTA + MAF, HEBP + MAF; and PAA + MAF was superior to EDTA + MAF, HEBP + MAF (P < 0.05). At middle thirds; PAA + MAF and PAA + UA were superior to EDTA + MAF and EDTA + UA; and, PAA + UA was superior to HEBP + MAF (P < 0.05). There were no significant differences among the rest of the experimental groups (P > 0.05). Complete removal of Ca(OH)2could not be achieved by none of the irrigants at all root thirds.

Evaluation of smear layer removal and marginal adaptation of root canal sealer after final irrigation using ethylenediaminetetraacetic, peracetic, and etidronic acids with different concentrations.

PubMed

Ulusoy, Özgür İlke; Zeyrek, Salev; Çelik, Bülent

2017-07-01

The purpose of this study was to investigate the effects of different irrigation solutions on the smear layer removal and marginal adaptation of a resin-based sealer to root canal dentine. A total of 152 instrumented roots were irrigated with the following irrigants: 9,18% etidronic acid (HEBP), 0.5, 1,2% peracetic acid (PAA), 17% ethylenediaminetetraacetic acid (EDTA), saline. The amount of smear layer was evaluated using scanning electron microscope (SEM) in seventy root samples. Eighty-two roots were filled with AH Plus and gutta-percha. Slices obtained from apical third of each specimen were viewed with SEM to assess marginal adaptation. Use of 9% and 18% HEBP resulted in more efficient smear layer removal in the apical third than the other chelators (p < 0.05). Higher smear layer scores in the coronal and middle thirds were obtained from 0.5%, 1% PAA groups. Regarding marginal adaptation, 18% HEBP group showed the lowest gap size values (p < 0.05), and better marginal adaptation. Etidronic acid is a promising candidate for final irrigation of root canals. © 2017 Wiley Periodicals, Inc.

The effect of passive ultrasonic activation of 2% chlorhexidine or 5.25% sodium hypochlorite irrigant on residual antimicrobial activity in root canals.

PubMed

Weber, Carol Diener; McClanahan, Scott B; Miller, Glenn A; Diener-West, Marie; Johnson, James D

2003-09-01

Ninety-four single-canal roots were prepared using the step-down technique. Forty-two canals were irrigated with 2% chlorhexidine, 42 canals with 5.25% sodium hypochlorite (NaOCl), and 10 control canals with phosphate-buffered saline (PBS). The chlorhexidine and NaOCl groups were each then equally divided into a final irrigation group and a 1-min passive ultrasonic irrigation group. Canals were enlarged with a Parapost drill. The apical 3-5 mm was covered with nail polish. Canals were rinsed with PBS, dried, refilled with PBS, and stored. At 6 h, 20 microl of fluid was pipetted from each canal and placed into wells on agar plates, which were inoculated with Streptococcus sanguinis. The plates were incubated, and zones of inhibition were measured. Sampling was repeated at 24, 48, 72, 96, 120, 144, and 168 h. Residual antimicrobial activity with 2% chlorhexidine was statistically significantly superior to 5.25% NaOCl with irrigation alone and with final passive ultrasonic activation (p < 0.001). Chlorhexidine experimental groups demonstrated residual antimicrobial activity for as long as 168 h.

Effect of super-oxidized water, sodium hypochlorite and EDTA on dentin microhardness.

PubMed

Ghisi, Alexandre Corrêa; Kopper, Patrícia Maria Poli; Baldasso, Flávia E R; Stürmer, Caroline P; Rossi-Fedele, Giampiero; Steier, Liviu; Figueiredo, José Antonio Poli de; Morgental, Renata Dornelles; Vier-Pelisser, Fabiana Vieira

2014-01-01

The present study aimed to evaluate the influence of the following irrigating solutions on the microhardness of root canal dentin: 2% sodium hypochlorite (2NaOCl), 5% sodium hypochlorite (5NaOCl), super-oxidized water (400 ppm Sterilox - Sx) and 17% EDTA (E). Eighty roots from bovine incisors were randomly divided into 8 groups (n=10): 2NaOCl, 5NaOCl, Sx, and 2NaOCl + E, 5NaOCl + E, Sx + E (associated with E as final irrigant for 5 min), E solely and distilled water (dH2O) as the negative control. Root canal preparation was performed by hand instruments, using one of the irrigation protocols for 30 min. Then, 5 mm of the cervical root third were cut out from each sample and subjected to the Vickers microhardness test, at two points, one at approximately 500-1000 µm from the root canal lumen (distance 1), and the other at approximately 500-1000 µm from the external root surface (distance 2). Data were analyzed by Wilcoxon and Kruskal-Wallis tests at 5% significance level. Microhardness values at distance 1 were significantly lower than those at distance 2 for all groups, except 5NaOCl and 5NaOCl + E groups (p>0.05). EDTA showed the lowest microhardness values. However, no statistically significant difference was detected among groups at distance 1 and EDTA was significantly different only from Sx at distance 2. In conclusion, all tested solutions showed lower microhardness at the most superficial root canal dentin layer compared to the one found near the external root surface, except 5NaOCl and 5NaOCl + E; EDTA promoted lower microhardness values in comparison to Sterilox at this site.

The effect of four different irrigation systems in the removal of a root canal sealer.

PubMed

Grischke, J; Müller-Heine, A; Hülsmann, M

2014-09-01

The aim of this study was to compare the efficiency of sonic, ultrasonic, and hydrodynamic devices in the removal of a root canal sealer from the surface and from simulated irregularities of root canals. Fifty-three root canals with two standardized grooves in the apical and coronal parts of longitudinally split roots were covered with AH Plus root canal sealer. Compared were the effects of (control) syringe irrigation, (1) CanalBrush, (2) passive ultrasonic irrigation, (3) EndoActivator, and (4) RinsEndo on the removal of the sealer. The specimens were divided into four groups (N = 12) and one control group (N = 5) via randomization. The amount of remaining sealer in the root canal irregularities was evaluated under a microscope using a 4-grade scoring system, whereas the remaining sealer on the root canal surface was evaluated with a 7-grade scoring system. Passive ultrasonic irrigation is more effective than the other tested irrigation systems or syringe irrigation in removing sealer from root canal walls (p < 0.01). None of the techniques had a significant effect on cleaning the lateral grooves. Within the limitations of this study protocol ultrasonic irrigation shows a superior effect on sealer removal from the root canal surface during endodontic retreatment. Cleaning of lateral grooves seems not to be possible with one of the techniques investigated. Incomplete removal of root canal sealer during re-treatment may cause treatment failure. Passive Ultrasonic irrigation seems to be the most effective system to remove sealer from a root canal.

Irrigation mitigates against heat extremes

NASA Astrophysics Data System (ADS)

Thiery, Wim; Fischer, Erich; Visser, Auke; Hirsch, Annette L.; Davin, Edouard L.; Lawrence, Dave; Hauser, Mathias; Seneviratne, Sonia I.

2017-04-01

Irrigation is an essential practice for sustaining global food production and many regional economies. Emerging scientific evidence indicates that irrigation substantially affects mean climate conditions in different regions of the world. Yet how this practice influences climate extremes is currently unknown. Here we use gridded observations and ensemble simulations with the Community Earth System Model to assess the impacts of irrigation on climate extremes. While the influence of irrigation on annual mean temperatures is limited, we find a large impact on temperature extremes, with a particularly strong cooling during the hottest day of the year (-0.78 K averaged over irrigated land). The strong influence on hot extremes stems from the timing of irrigation and its influence on land-atmosphere coupling strength. Together these effects result in asymmetric temperature responses, with a more pronounced cooling during hot and/or dry periods. The influence of irrigation is even more pronounced when considering subgrid-scale model output, suggesting that local effects of land management are far more important than previously thought. Finally we find that present-day irrigation is partly masking GHG-induced warming of extreme temperatures, with particularly strong effects in South Asia. Our results overall underline that irrigation substantially reduces our exposure to hot temperature extremes and highlight the need to account for irrigation in future climate projections.

Efficiency of Different Endodontic Irrigation and Activation Systems in Removal of the Smear Layer: A Scanning Electron Microscopy Study.

PubMed

Karade, Priyatam; Chopade, Rutuja; Patil, Suvarna; Hoshing, Upendra; Rao, Madhukar; Rane, Neha; Chopade, Aditi; Kulkarni, Anish

2017-01-01

This in vitro study was designed to evaluate and compare different endodontic irrigation and activation systems for removal of the intracanal smear layer. Forty recently extracted, non-carious human intact single rooted premolars were selected and divided into five groups ( n =10) according to the root canal irrigation systems; syringe and needle irrigation (CTR), sonic irrigation, passive ultrasonic irrigation (PUI) and EndoVac irrigation system. All groups were prepared to #40 apical size with K-files. Each sample was subjected to final irrigation by using four different irrigation/activation systems. After splitting the samples, one half of each root was selected for examination under scanning electron microscope (SEM). The irrigation systems were compared using the Fisher's exact test with the level of significance set at 0.05. The four groups did not differ from each other in the coronal and mid-root parts of the canal. In the apical part of the canal none of the methods could completely remove all the smear layer but EndoVac system showed significantly better removal of smear layer and debris than the other methods. Within the limitations of the present study, the EndoVac system cleaned the apical part of the canal more efficiently than sonic, ultrasonic and syringe and needle irrigation.

Antibacterial Efficacy of Calcium Hypochlorite with Vibringe Sonic Irrigation System on Enterococcus faecalis: An In Vitro Study

PubMed Central

Dumani, Aysin; Guvenmez, Hatice Korkmaz; Yilmaz, Sehnaz; Yoldas, Oguz; Kurklu, Zeliha Gonca Bek

2016-01-01

Aim. The purpose of this study was to compare the in vitro efficacy of calcium hypochlorite (Ca[OCl]2) and sodium hypochlorite (NaOCl) associated with sonic (Vibringe) irrigation system in root canals which were contaminated with Enterococcus faecalis. Material and Methods. The root canals of 84 single-rooted premolars were enlarged up to a file 40, autoclaved, inoculated with Enterococcus faecalis, and incubated for 21 days. The samples were divided into 7 groups according to the irrigation protocol: G0: no treatment; G1: distilled water; G2: 2.5% NaOCl; G3: 2.5% Ca(OCl)2; G4: distilled water with sonic activation; G5: 2.5% NaOCl with sonic activation; and G6: 2.5% Ca(OCl)2 with sonic activation. Before and after decontamination procedures microbiological samples were collected and the colony-forming units were counted and the percentages of reduction were calculated. Results. Distilled water with syringe irrigation and sonic activation groups demonstrated poor antibacterial effect on Enterococcus faecalis compared to other experimental groups (p < 0.05). There was no statistically significant difference between syringe and sonic irrigation systems with Ca(OCl)2 and NaOCl. Conclusion. The antimicrobial property of Ca(OCl)2 has been investigated and compared with that of NaOCl. Both conventional syringe irrigation and sonic irrigation were found effective at removing E. faecalis from the root canal of extracted human teeth. PMID:27218106

7 CFR 1437.104 - Assigned production.

Code of Federal Regulations, 2011 CFR

2011-01-01

.... (4) The crop is planted after the STC-established final planting date according to § 1437.103. (5) Irrigation equipment is not capable of supplying adequate water to sustain the expected production of a... practice is not used. (7) For normal irrigated annual and biennial crops, the supply of available water at...

Representing Water Scarcity in Future Agricultural Assessments

NASA Technical Reports Server (NTRS)

Winter, Jonathan M.; Lopez, Jose R.; Ruane, Alexander C.; Young, Charles A.; Scanlon, Bridget R.; Rosenzweig, Cynthia

2017-01-01

Globally, irrigated agriculture is both essential for food production and the largest user of water. A major challenge for hydrologic and agricultural research communities is assessing the sustainability of irrigated croplands under climate variability and change. Simulations of irrigated croplands generally lack key interactions between water supply, water distribution, and agricultural water demand. In this article, we explore the critical interface between water resources and agriculture by motivating, developing, and illustrating the application of an integrated modeling framework to advance simulations of irrigated croplands. We motivate the framework by examining historical dynamics of irrigation water withdrawals in the United States and quantitatively reviewing previous modeling studies of irrigated croplands with a focus on representations of water supply, agricultural water demand, and impacts on crop yields when water demand exceeds water supply. We then describe the integrated modeling framework for simulating irrigated croplands, which links trends and scenarios with water supply, water allocation, and agricultural water demand. Finally, we provide examples of efforts that leverage the framework to improve simulations of irrigated croplands as well as identify opportunities for interventions that increase agricultural productivity, resiliency, and sustainability.

Development of a regionally consistent geospatial dataset of agricultural lands in the Upper Colorado River Basin, 2007-10

USGS Publications Warehouse

Buto, Susan G.; Gold, Brittany L.; Jones, Kimberly A.

2014-01-01

Irrigation in arid environments can alter the natural rate at which salts are dissolved and transported to streams. Irrigated agricultural lands are the major anthropogenic source of dissolved solids in the Upper Colorado River Basin (UCRB). Understanding the location, spatial distribution, and irrigation status of agricultural lands and the method used to deliver water to agricultural lands are important to help improve the understanding of agriculturally derived dissolved-solids loading to surface water in the UCRB. Irrigation status is the presence or absence of irrigation on an agricultural field during the selected growing season or seasons. Irrigation method is the system used to irrigate a field. Irrigation method can broadly be grouped into sprinkler or flood methods, although other techniques such as drip irrigation are used in the UCRB. Flood irrigation generally causes greater dissolved-solids loading to streams than sprinkler irrigation. Agricultural lands in the UCRB mapped by state agencies at varying spatial and temporal resolutions were assembled and edited to represent conditions in the UCRB between 2007 and 2010. Edits were based on examination of 1-meter resolution aerial imagery collected between 2009 and 2011. Remote sensing classification techniques were used to classify irrigation status for the June to September growing seasons between 2007 and 2010. The final dataset contains polygons representing approximately 1,759,900 acres of agricultural lands in the UCRB. Approximately 66 percent of the mapped agricultural lands were likely irrigated during the study period.

Temperature Changes in Cortical Bone after Implant Site Preparation Using a Single Bur versus Multiple Drilling Steps: An In Vitro Investigation.

PubMed

Gehrke, Sergio Alexandre; Bettach, Raphaél; Taschieri, Silvio; Boukhris, Gilles; Corbella, Stefano; Del Fabbro, Massimo

2015-08-01

The study aims to test the hypothesis of no differences in temperature variation by using a single bur for implant site preparation as compared with conventional drilling sequence using multiple burs with incremental diameter. Synthetic blocks of bone (type I density) were used for drilling procedures. Group 1 and Group 2 - drilling with three consecutive burs for a 4.1 mm cylindrical implant and for a 4.3 mm conical implant, respectively; Group 3 - drilling with a single bur for a 4.2 mm conical implant. For each group, 20 drilling procedures were performed without irrigation and 20 with external irrigation. The temperature in the cortical bone during osteotomy for implant site preparation was measured through a thermocouple. The mean temperatures and standard deviations for the drilling without irrigation were: 25.5 ± 1.24°C for Group 1; 28.1 ± 1.76°C for Group 2; 26.5 ± 1.79°C for Group 3. Considering the drilling with irrigation, the mean values and standard deviations were: 20.4 ± 1.17°C for Group 1; 22.2 ± 1.38°C for Group 2; 20.2 ± 0.83°C for Group 3. Groups 1 and 3 yielded similar results, while Group 2 displayed significantly higher temperature increase than the other two groups. The single bur drilling protocol did not produce greater bone heating than the conventional protocol and may be considered a safe procedure. © 2013 Wiley Periodicals, Inc.

Efficacy of 4 Irrigation Protocols in Killing Bacteria Colonized in Dentinal Tubules Examined by a Novel Confocal Laser Scanning Microscope Analysis

PubMed Central

Azim, Adham A.; Aksel, Hacer; Zhuang, Tingting; Mashtare, Terry; Babu, Jegdish P.; Huang, George T.-J.

2016-01-01

Introduction The aim of this study was to determine the efficiency of 4 irrigation systems in eliminating bacteria in root canals, particularly in dentinal tubules. Methods Roots of human teeth were prepared to 25/04, autoclaved, and inoculated with Enterococcus faecalis for 3 weeks. Canals were then disinfected by (1) standard needle irrigation, (2) sonically agitating with EndoActivator, (3) XP Endo finisher, or (4) erbium:yttrium aluminum garnet laser (PIPS) (15 roots/group). The bacterial reduction in the canal was determined by MTT assays. For measuring live versus dead bacteria in the dentinal tubules (4 teeth/group), teeth were split open and stained with LIVE/DEAD BackLight. Coronal, middle, and apical thirds of the canal dentin were scanned by using a confocal laser scanning microscope (CLSM) to determine the ratio of dead/total bacteria in the dentinal tubules at various depths. Results All 4 irrigation protocols significantly eliminated bacteria in the canal, ranging from 89.6% to 98.2% reduction (P < .001). XP Endo had the greatest bacterial reduction compared with other 3 techniques (P < .05). CLSM analysis showed that XP Endo had the highest level of dead bacteria in the coronal, middle, and apical segments at 50-μm depth. On the other hand, PIPS had the greatest bacterial killing efficiency at the 150-μm depth in all 3 root segments. Conclusions XP Endo appears to be more efficient than other 3 techniques in disinfecting the main canal space and up to 50 μm deep into the dentinal tubules. PIPS appears to be most effective in killing the bacteria deep in the dentinal tubules. PMID:27130334

Efficacy of 4 Irrigation Protocols in Killing Bacteria Colonized in Dentinal Tubules Examined by a Novel Confocal Laser Scanning Microscope Analysis.

PubMed

Azim, Adham A; Aksel, Hacer; Zhuang, Tingting; Mashtare, Terry; Babu, Jegdish P; Huang, George T-J

2016-06-01

The aim of this study was to determine the efficiency of 4 irrigation systems in eliminating bacteria in root canals, particularly in dentinal tubules. Roots of human teeth were prepared to 25/04, autoclaved, and inoculated with Enterococcus faecalis for 3 weeks. Canals were then disinfected by (1) standard needle irrigation, (2) sonically agitating with EndoActivator, (3) XP Endo finisher, or (4) erbium:yttrium aluminum garnet laser (PIPS) (15 roots/group). The bacterial reduction in the canal was determined by MTT assays. For measuring live versus dead bacteria in the dentinal tubules (4 teeth/group), teeth were split open and stained with LIVE/DEAD BackLight. Coronal, middle, and apical thirds of the canal dentin were scanned by using a confocal laser scanning microscope (CLSM) to determine the ratio of dead/total bacteria in the dentinal tubules at various depths. All 4 irrigation protocols significantly eliminated bacteria in the canal, ranging from 89.6% to 98.2% reduction (P < .001). XP Endo had the greatest bacterial reduction compared with other 3 techniques (P < .05). CLSM analysis showed that XP Endo had the highest level of dead bacteria in the coronal, middle, and apical segments at 50-μm depth. On the other hand, PIPS had the greatest bacterial killing efficiency at the 150-μm depth in all 3 root segments. XP Endo appears to be more efficient than other 3 techniques in disinfecting the main canal space and up to 50 μm deep into the dentinal tubules. PIPS appears to be most effective in killing the bacteria deep in the dentinal tubules. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Photodynamic therapy with two different photosensitizers as a supplement to instrumentation/irrigation procedures in promoting intracanal reduction of Enterococcus faecalis.

PubMed

Souza, Letícia C; Brito, Patrícia R R; de Oliveira, Julio C Machado; Alves, Flávio R F; Moreira, Edson J L; Sampaio-Filho, Hélio R; Rôças, Isabela N; Siqueira, José F

2010-02-01

This in vitro study aimed to investigate the antibacterial effects of photodynamic therapy (PDT) with methylene blue (MB) or toluidine blue (TB) (both at 15 microg/mL) as a supplement to instrumentation/irrigation of root canals experimentally contaminated with Enterococcus faecalis. Seventy extracted teeth had their root canals contaminated with an endodontic strain of E. faecalis for 7 days, instrumented with nickel-titanium instruments and irrigated either with 2.5% NaOCl or with 0.85% NaCl, and then randomly distributed into four experimental groups: MB/NaOCl (PDT with MB and NaOCl as the irrigant), TB/NaOCl (PDT with TB and NaOCl as the irrigant), MB/NaCl (PDT with MB and NaCl as the irrigant), and TB/NaCl (PDT with TB and NaCl as the irrigant). For PDT, the photosensitizer remained in the canal for 2 minutes before exposed to red light emitted from a diode laser for 4 minutes. Samples were taken before and after instrumentation/irrigation and following the specific PDT procedure for each group, plated onto Mitis-salivarius agar and the colony forming units counted. Regardless of the irrigant used (NaOCl or NaCl), instrumentation significantly reduced bacterial counts in comparison to the baseline (p < 0.001). NaOCl as the irrigant was significantly more effective than NaCl, and this difference persisted after PDT, irrespective of the photosensitizer used (p < 0.05). PDT with either MB or TB did not significantly enhance disinfection after chemomechanical preparation using NaOCl as irrigant (p > 0.05). No significant differences were observed between the two photosensitizers (p > 0.05). These in vitro results suggest that PDT with either MB or TB may not exert a significant supplemental effect to instrumentation/irrigation procedures with regard to intracanal disinfection. Further adjustments in the PDT protocol may be required to enhance predictability in bacterial elimination before clinical use is recommended. Copyright 2010 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Effects of varying pulsatile lavage pressure on cancellous bone structure and fracture healing.

PubMed

Polzin, Britton; Ellis, Thomas; Dirschl, Douglas R

2006-04-01

To study the effects of variations in pulsatile lavage irrigation pressure on the rate of new bone formation and the degree to which cellular elements are removed from cancellous bone after fracture. A previously described intraarticular fracture model was used for 29 New Zealand white rabbits that underwent osteotomy of the medial femoral condyle. Fractures were irrigated with high-pressure pulsatile lavage at a fixed distance and volume, but at nozzle pressures varying from 20 to 70 psi. Fractures were reduced and stabilized, and animals euthanized 14 days after fracture. Fluorescent bone staining was used to determine the rate of new bone formation in the osteotomy site. At the time of euthanasia, the nonoperated knees of 12 rabbits underwent osteotomy and irrigation using the same protocol. These specimens were sent for immediate scanning electron microscopy to determine the amount of cellular material removed from the bony trabeculae. In the first week after irrigation, there was no significant difference in the amount of new bone formation between the 20- and 30-psi groups, but there were significant differences between these groups and the 50- and 70-psi groups. There were no significant differences between any of the groups in the amount of new bone formed during the second week after irrigation. No structural damage to the bony trabeculae was observed in any specimen irrigated at any of the pressures used. There was a direct correlation between percentage of the trabecula completely cleared of cellular material and irrigation pressure; there were statistically significant differences between each of the groups. There are presently no recommended guidelines as to the optimal irrigation pressure, and this study is the first to address the effects of variations in pressure on bone healing. The results of this study indicate that early new bone formation in an intraarticular fracture rabbit model is inhibited by irrigation pressure of 50 psi or greater. Additionally, this study demonstrates a direct relationship between irrigation pressure and the amount of cellular material removed from the trabecula at the irrigation site. Surgeons should be aware of the potentially detrimental effects of using irrigation pressures at or above 50 psi in the treatment of fractures.

Research on the autumn irrigation schedule of Hetao Irrigation District of China

NASA Astrophysics Data System (ADS)

Han, Y.

2016-12-01

Salinization of soil has great influence on the function of crop land, leading to the crop failure to some extent. One of the inducement of salinization is that the water pressure of frozen soil is lower than that of unfrozen, salt is drew up to the frozen layer along with water during the freezing process. To prevent the salinization of soil, people carry out the autumn irrigation in Hetao Irrigation District which located is located in Bayannur City, Inner Mongolia, north of China. Autumn irrigation is an irrigation event before the freezing of soil, the function of autumn irrigation includes soil moisture conservation, loosening the soil and leaching the salt. Among all the crop models, none is designed to simulate the water and salt movement during freezing and thawing progress. So In this study, SWAP (Soil Water Atmosphere Plant) model is modified by adding the freezing and thawing module which enable the model to take into consideration the effect of freezing and thawing on water and salt movement. After validating the modified model using field data and lab test results, the model was used to simulate the results of various autumn irrigation schedules, exploring the influence of different autumn irrigation amounts on the water, salt and heat condition and transportation of soil. Finally, proper autumn irrigation schedule was obtained to instruct the production of Hetao Irrigation District.

Revascularization and periapical repair after endodontic treatment using apical negative pressure irrigation versus conventional irrigation plus triantibiotic intracanal dressing in dogs' teeth with apical periodontitis.

PubMed

da Silva, Lea Assed Bezerra; Nelson-Filho, Paulo; da Silva, Raquel Assed Bezerra; Flores, Daniel Silva Herzog; Heilborn, Carlos; Johnson, James D; Cohenca, Nestor

2010-05-01

The objective of this study was to evaluate in vivo the revascularization and the apical and periapical repair after endodontic treatment using 2 techniques for root canal disinfection (apical negative pressure irrigation versus apical positive pressure irrigation plus triantibiotic intracanal dressing) in immature dogs' teeth with apical periodontitis. Two test groups of canals with experimentally induced apical periodontitis were evaluated according to the disinfection technique: Group 1, apical negative pressure irrigation (EndoVac system), and Group 2, apical positive pressure irrigation (conventional irrigation) plus triantibiotic intracanal dressing. In Group 3 (positive control), periapical lesions were induced, but no endodontic treatment was done. Group 4 (negative control) was composed of sound teeth. The animals were killed after 90 days and the maxillas and mandibles were subjected to histological processing. The sections were stained with hematoxylin and eosin and Mallory Trichrome and examined under light microscopy. A description of the apical and periapical features was done and scores were attributed to the following histopathological parameters: newly formed mineralized apical tissue, periapical inflammatory infiltrate, apical periodontal ligament thickness, dentin resorption, and bone tissue resorption. Intergroup comparisons were done by the Kruskal-Wallis and Dunn's tests (alpha = 0.05). Although statistically significant difference was found only for the inflammatory infiltrate (P < .05), Group 1 presented more exuberant mineralized formations, more structured apical and periapical connective tissue, and a more advanced repair process than Group 2. From the histological observations, sodium hypochlorite irrigation with the EndoVac system can be considered as a promising disinfection protocol in immature teeth with apical periodontitis, suggesting that the use of intracanal antibiotics might not be necessary. Copyright (c) 2010 Mosby, Inc. All rights reserved.

Land use policy and agricultural water management of the previous half of century in Africa

NASA Astrophysics Data System (ADS)

Valipour, Mohammad

2015-12-01

This paper examines land use policy and agricultural water management in Africa from 1962 to 2011. For this purpose, data were gathered from Food and Agriculture Organization of the United Nations (FAO) and the World Bank Group. Using the FAO database, ten indices were selected: permanent crops to cultivated area (%), rural population to total population (%), total economically active population in agriculture to total economically active population (%), human development index, national rainfall index (mm/year), value added to gross domestic product by agriculture (%), irrigation water requirement (mm/year), percentage of total cultivated area drained (%), difference between national rainfall index and irrigation water requirement (mm/year), area equipped for irrigation to cultivated area or land use policy index (%). These indices were analyzed for all 53 countries in the study area and the land use policy index was estimated by two different formulas. The results show that value of relative error is <20 %. In addition, an average index was calculated using various methods to assess countries' conditions for agricultural water management. Ability of irrigation and drainage systems was studied using other eight indices with more limited information. These indices are surface irrigation (%), sprinkler irrigation (%), localized irrigation (%), spate irrigation (%), agricultural water withdrawal (10 km3/year), conservation agriculture area as percentage of cultivated area (%), percentage of area equipped for irrigation salinized (%), and area waterlogged by irrigation (%). Finally, tendency of farmers to use irrigation systems for cultivated crops has been presented. The results show that Africa needs governments' policy to encourage farmers to use irrigation systems and raise cropping intensity for irrigated area.

Evaluation of dripper clogging using magnetic water in drip irrigation

NASA Astrophysics Data System (ADS)

Khoshravesh, Mojtaba; Mirzaei, Sayyed Mohammad Javad; Shirazi, Pooya; Valashedi, Reza Norooz

2018-06-01

This study was performed to investigate the uniformity of distribution of water and discharge variations in drip irrigation using magnetic water. Magnetic water was achieved by transition of water using a robust permanent magnet connected to a feed pipeline. Two main factors including magnetic and non-magnetic water and three sub-factor of salt concentration including well water, addition of 150 and 300 mg L-1 calcium carbonate to irrigation water with three replications were applied. The result of magnetic water on average dripper discharge was significant at ( P ≤ 0.05). At the final irrigation, the average dripper discharge and distribution uniformity were higher for the magnetic water compared to the non-magnetic water. The magnetic water showed a significant effect ( P ≤ 0.01) on distribution uniformity of drippers. At the first irrigation, the water distribution uniformity was almost the same for both the magnetic water and the non-magnetic water. The use of magnetic water for drip irrigation is recommended to achieve higher uniformity.

Comparison of the Antimicrobial Efficacy of Octenidine Dihydrochloride and Chlorhexidine with and Without Passive Ultrasonic Irrigation - An Invitro Study.

PubMed

Cherian, Bastin; Gehlot, Paras Mull; Manjunath, Mysore Krishnaswamy

2016-06-01

Elimination of microorganisms from infected root canals is a complicated task. Numerous measures have been described to reduce the microbial load in the root canal system, including the use of various instrumentation techniques, irrigation regimens and intracanal medicaments. The drawbacks of few commonly used irrigants include toxic and harmful side effects, microbial resistance to antimicrobial agents and staining. Hence there is a need for alternative agents which are nontoxic, effective and safe. To compare and evaluate antimicrobial effects of 2% Chlorhexidine (CHX) versus 0.1% Octenidine Dihydrochloride (OCT) as root canal irrigant with and without passive ultrasonic irrigation against Enterococcus faecalis (E. faecalis) in vitro and to evaluate the depth of penetration of irrigant solution into the dentinal tubules at the junction of middle and apical third. Forty eight freshly extracted, single rooted human mandibular premolars were decoronated and root specimen standardized to 14mm. Biofilm of E. faecalis (strain ATCC 29212) was grown for seven days and the specimens were divided into four groups (n=12) based on irrigation protocol : Group I- Conventional Syringe Irrigation (CSI) with 2% CHX, Group II- CSI + 0.1% OCT, Group III-Passive Ultrasonic Irrigation (PUI) + 2% CHX and Group IV- PUI+ 0.1% OCT. Dentin shavings were collected at two depths (200μm and 400μm) and total number of colony forming units were determined. The data were statistically analyzed using ANOVA, Scheffes multiple comparison of means and paired t-test (p<0.05). Group III and IV (PUI) showed significant difference compared to Group I and II (CSI) both at 200μm and 400μm (p=0.000). For Group III and Group IV no significant differences were found at 200μm and 400μm (p=1.000 and 0.363 respectively), however significant difference was found between data at 200μm and 400μm for all the four groups (p=0.000). Octenidine (0.1%) was more effective than 2% Chlorhexidine against E. faecalis both at 200μm and 400μm. Passive ultrasonic irrigation proved to enhance the antimicrobial action of the irrigants.

Aerial thermal images to assess irrigation efficiency in 'Vitis vinifera' cv. Albariño

NASA Astrophysics Data System (ADS)

Gonzalez, Xesús Pablo; Fandiño, María; Rey, Benjamín J.; José Cancela, Javier

2017-04-01

Canopy temperature was defined as key data to irrigation management and to detect crop water stress (Jackson, 1982). Recently, temperature camera was installed on board in a Unmanned Aerial Vehicle (UAV), thus heterogeneity within field could be determined. Pereira et al. (2012) have defined the conceptual and terminological study of crop water use indicators, mainly water use efficiency (WUE) and water productivity (WP). Actually, it is crucial achieve higher WP and WUE, where crop yield variability between years must be reduced with the smallest irrigation water, but with a correct management of crop water stress during the season. In this study, Albariño cultivar grapevine, priority in Galicia (Spain) in Designation of Origen 'Rías Baixas', was assessed in relation to water productivity index, focus on irrigation treatments aspects, during 2016. Albariño vineyard was planted in 1996 on 110-Richter at a spacing of 3 × 2 m (1667 vines ha-1) (41°57 6 N, 8°49 26 W, elevation 101 m). Vines were trained to a vertical trellis system on a Guyot oriented in the East-West direction. Three irrigation treatments were applied: irrigation from budburst to maturation (T1), from flowering to maturation (T2), and from veraison to maturation (T3), moreover a rain-fed treatment was implemented. All WP index was referred to farm yield level (kg ha-1); where the denominator applied to WP TWUfarm, introduced rainfall and irrigation depth; to WP Irrig, only irrigation depth applied; was used. Moreover, crop water stress index (CWSI) was used to determine homogenize areas within experimental plot, using an UAV with a thermal camera (ThermoMAP, senseFly, SW) to achieve a final map with 14 cm per pixel resolution. During August 11th, at the end of veraison, camera was installed in an 'eBee Ag' UAV (senseFly, SW) with a median flight altitude of 75 m over ground level. Yield per hectare were recorded and total irrigation depth per treatment during the growing season from March to harvest. Preliminary results have showed that CWSI is useful to determine heterogeneity areas within field, concretely areas with identic irrigation treatments were grouped in a similar range, a good correlation was achieved with steam water potential measured in verasion during the flight. This aspect permit establishes a tool to manage irrigation with efficiency, during the growing season, using thermal data and CWSI. Finally, WP were higher in rain-fed than irrigated treatments, where T3 treatment showed higher WP Irrig, than T1 and T2 treatments. A new step Economic aspects should be studied, taken into account benefit crop yield, and cost of pumping irrigation water. References: Jackson, RD (1982). Canopy temperature and crop water stress. Advances in irrigation, 1:43-85 Pereira LS, Cordery I, Iacovides I (2012). Improved indicators of water use performance and productivity for sustainable water conservation and saving. Agricultural Water Management, 108:39-51

Carbon and water footprints of irrigated corn and non-irrigated wheat in Northeast Spain.

PubMed

Abrahão, Raphael; Carvalho, Monica; Causapé, Jesús

2017-02-01

Irrigation increases yields and allows several crops to be produced in regions where it would be naturally impossible due to limited rainfall. However, irrigation can cause several negative environmental impacts, and it is important to understand these in depth for the correct application of mitigation measures. The life cycle assessment methodology was applied herein to compare the main irrigated and non-irrigated crops in Northeast Spain (corn and wheat, respectively), identifying those processes with greater contribution to environmental impacts (carbon and water footprint categories) and providing scientifically-sound information to facilitate government decisions. Due to concerns about climate change and water availability, the methods selected for evaluation of environmental impacts were IPCC 2013 GWP (carbon footprint) and water scarcity indicator (water footprint). The area studied, a 7.38-km 2 basin, was monitored for 12 years, including the period before, during, and after the implementation of irrigation. The functional unit, to which all material and energy flows were associated with, was the cultivation of 1 ha, throughout 1 year. The overall carbon footprint for irrigated corn was higher, but when considering the higher productivity achieved with irrigation, the emissions per kilogram of corn decrease and finally favor this irrigated crop. When considering the water footprint, the volumes of irrigation water applied were so high that productivity could not compensate for the negative impacts associated with water use in the case of corn. Nevertheless, consideration of productivities and gross incomes brings the results closer. Fertilizer use (carbon footprint) and irrigation water (water footprint) were the main contributors to the negative impacts detected.

Is current irrigation sustainable in the United States? An integrated assessment of climate change impact on water resources and irrigated crop yields

NASA Astrophysics Data System (ADS)

Blanc, Elodie; Caron, Justin; Fant, Charles; Monier, Erwan

2017-08-01

While climate change impacts on crop yields has been extensively studied, estimating the impact of water shortages on irrigated crop yields is challenging because the water resources management system is complex. To investigate this issue, we integrate a crop yield reduction module and a water resources model into the MIT Integrated Global System Modeling framework, an integrated assessment model linking a global economic model to an Earth system model. We assess the effects of climate and socioeconomic changes on water availability for irrigation in the U.S. as well as subsequent impacts on crop yields by 2050, while accounting for climate change projection uncertainty. We find that climate and socioeconomic changes will increase water shortages and strongly reduce irrigated yields for specific crops (i.e., cotton and forage), or in specific regions (i.e., the Southwest) where irrigation is not sustainable. Crop modeling studies that do not represent changes in irrigation availability can thus be misleading. Yet, since the most water-stressed basins represent a relatively small share of U.S. irrigated areas, the overall reduction in U.S. crop yields is small. The response of crop yields to climate change and water stress also suggests that some level of adaptation will be feasible, like relocating croplands to regions with sustainable irrigation or switching to less irrigation intensive crops. Finally, additional simulations show that greenhouse gas (GHG) mitigation can alleviate the effect of water stress on irrigated crop yields, enough to offset the reduced CO2 fertilization effect compared to an unconstrained GHG emission scenario.

Is current irrigation sustainable in the United States? An integrated assessment of climate change impact on water resources and irrigated crop yields.

PubMed

Blanc, Elodie; Caron, Justin; Fant, Charles; Monier, Erwan

2017-08-01

While climate change impacts on crop yields has been extensively studied, estimating the impact of water shortages on irrigated crop yields is challenging because the water resources management system is complex. To investigate this issue, we integrate a crop yield reduction module and a water resources model into the MIT Integrated Global System Modeling framework, an integrated assessment model linking a global economic model to an Earth system model. We assess the effects of climate and socioeconomic changes on water availability for irrigation in the U.S. as well as subsequent impacts on crop yields by 2050, while accounting for climate change projection uncertainty. We find that climate and socioeconomic changes will increase water shortages and strongly reduce irrigated yields for specific crops (i.e., cotton and forage), or in specific regions (i.e., the Southwest) where irrigation is not sustainable. Crop modeling studies that do not represent changes in irrigation availability can thus be misleading. Yet, since the most water-stressed basins represent a relatively small share of U.S. irrigated areas, the overall reduction in U.S. crop yields is small. The response of crop yields to climate change and water stress also suggests that some level of adaptation will be feasible, like relocating croplands to regions with sustainable irrigation or switching to less irrigation intensive crops. Finally, additional simulations show that greenhouse gas (GHG) mitigation can alleviate the effect of water stress on irrigated crop yields, enough to offset the reduced CO 2 fertilization effect compared to an unconstrained GHG emission scenario.

Groundwater economics: An object-oriented foundation for integrated studies of irrigated agricultural systems

NASA Astrophysics Data System (ADS)

Steward, David R.; Peterson, Jeffrey M.; Yang, Xiaoying; Bulatewicz, Tom; Herrera-Rodriguez, Mauricio; Mao, Dazhi; Hendricks, Nathan

2009-05-01

An integrated foundation is presented to study the impacts of external forcings on irrigated agricultural systems. Individually, models are presented that simulate groundwater hydrogeology and econometric farm level crop choices and irrigated water use. The natural association between groundwater wells and agricultural parcels is employed to couple these models using geographic information science technology and open modeling interface protocols. This approach is used to study the collective action problem of the common pool. Three different policies (existing, regulation, and incentive based) are studied in the semiarid grasslands overlying the Ogallala Aquifer in the central United States. Results show that while regulation using the prior appropriation doctrine and incentives using a water buy-back program may each achieve the same level of water savings across the study region, each policy has a different impact on spatial patterns of groundwater declines and farm level economic activity. This represents the first time that groundwater and econometric models of irrigated agriculture have been integrated at the well-parcel level and provides methods for scientific investigation of this coupled natural-human system. Results are useful for science to inform decision making and public policy debate.

Root canal obturation: experimental study on the thermafil system related to different irrigation protocols

PubMed Central

Migliau, Guido; Sofan, Afrah Ali Abdullah; Sofan, Eshrak Ali Abdullah; Cosma, Salvatore; Eramo, Stefano; Gallottini, Livio

2014-01-01

Summary Aim The aim of this study was to stress the ability of a specific obturation technique (thermafil technique) to seal root canal system in presence or absence of smear layer. Methodology Sixteen monoradicular teeth, extracted for periodontal reasons, were collected for this study. All specimens were prepared with nickel-titanium rotary files, and then divided into two groups: for each group was applied a different kind of irrigation method, verifying the effectiveness in removing the smear layer, thus rendering the dentinal tubules more permeable for penetration of softened gutta-percha. Thermafil system was used to fill the root canals, and then all the specimens were observed under scanning electron microscope (SEM). Results The results showed that the Group which followed irrigation only with sodium hypochlorite exhibited significantly less gutta-percha tags when compared to the second Group, which was irrigated with sodium hypochlorite and EDTA. Conclusion The thermafil systems have a very good quality of compression and fluency that permit to gain a good seal of endodontic space; furthermore it allows the penetration of gutta-percha with the formation of numerous of gutta-percha tags inside the dentinal tubules above all when smear layer is reduced or eliminated. PMID:25506413

Soil Salt Distribution and Tomato Response to Saline Water Irrigation under Straw Mulching

PubMed Central

Zhai, Yaming; Yang, Qian; Wu, Yunyu

2016-01-01

To investigate better saline water irrigation scheme for tomatoes that scheduling with the compromise among yield (Yt), quality, irrigation water use efficiency (IWUE) and soil salt residual, an experiment with three irrigation quotas and three salinities of irrigation water was conducted under straw mulching in northern China. The irrigation quota levels were 280 mm (W1), 320 mm (W2) and 360 mm (W3), and the salinity levels were 1.0 dS/m (F), 3.0 dS/m (S1) and 5.0 dS/m (S2). Compared to freshwater, saline water irrigations decreased the maximum leaf area index (LAIm) of tomatoes, and the LAIm presented a decline tendency with higher salinity and lower irrigation quota. The best overall quality of tomato was obtained by S2W1, with the comprehensive quality index of 3.61. A higher salinity and lower irrigation quota resulted in a decrease of individual fruit weight and an increase of the blossom-end rot incidence, finally led to a reduction in the tomato Yt and marketable yield (Ym). After one growth season of tomato, the mass fraction of soil salt in plough layer under S2W1 treatment was the highest, and which presented a decline trend with an increasing irrigation quota. Moreover, compared to W1, soil salts had a tendency to move to the deeper soil layer when using W2 and W3 irrigation quota. According to the calculation results of projection pursuit model, S1W3 was the optimal treatment that possessed the best comprehensive benefit (tomato overall quality, Yt, Ym, IWUE and soil salt residual), and was recommended as the saline water irrigation scheme for tomatoes in northern China. PMID:27806098

Soil Salt Distribution and Tomato Response to Saline Water Irrigation under Straw Mulching.

PubMed

Zhai, Yaming; Yang, Qian; Wu, Yunyu

2016-01-01

To investigate better saline water irrigation scheme for tomatoes that scheduling with the compromise among yield (Yt), quality, irrigation water use efficiency (IWUE) and soil salt residual, an experiment with three irrigation quotas and three salinities of irrigation water was conducted under straw mulching in northern China. The irrigation quota levels were 280 mm (W1), 320 mm (W2) and 360 mm (W3), and the salinity levels were 1.0 dS/m (F), 3.0 dS/m (S1) and 5.0 dS/m (S2). Compared to freshwater, saline water irrigations decreased the maximum leaf area index (LAIm) of tomatoes, and the LAIm presented a decline tendency with higher salinity and lower irrigation quota. The best overall quality of tomato was obtained by S2W1, with the comprehensive quality index of 3.61. A higher salinity and lower irrigation quota resulted in a decrease of individual fruit weight and an increase of the blossom-end rot incidence, finally led to a reduction in the tomato Yt and marketable yield (Ym). After one growth season of tomato, the mass fraction of soil salt in plough layer under S2W1 treatment was the highest, and which presented a decline trend with an increasing irrigation quota. Moreover, compared to W1, soil salts had a tendency to move to the deeper soil layer when using W2 and W3 irrigation quota. According to the calculation results of projection pursuit model, S1W3 was the optimal treatment that possessed the best comprehensive benefit (tomato overall quality, Yt, Ym, IWUE and soil salt residual), and was recommended as the saline water irrigation scheme for tomatoes in northern China.

Soybean Photosynthesis and Yield as Influenced by Heterodera glycines, Soil Type and Irrigation.

PubMed

Koenning, S R; Barker, K R

1995-03-01

The effects of soil types and soil water matric pressure on the Heterodera glycines-Glycine max interaction were examined in microplots in 1988 and 1989. Reproduction of H. glycines was restricted in fine-textured soils as compared with coarse-textured ones. Final population densities of this pathogen in both years of the study were greater in nonirrigated soils than in irrigated soils. The net photosynthetic rate of soybean (per unit area of leaf) was suppressed only slightly or not at all in response to infection by H. glycines and other stresses. Relative soybean-yield suppression in response to H. glycines was not affected by water content in fine-textured soils, but slopes of the damage functions were steepest in sand, sandy loam, and muck soils at high water content (irrigated plots). Yield restriction of soybean in response to this pathogen under irrigation was equal to or greater than the yield suppression under dry conditions. Although yield potential may be elevated by irrigation when soil-water content is inadequate, supplemental irrigation cannot be used to circumvent nematode damage to soybean.

The role of remotely sensed and other spatial data for predictive modeling: the Umatilla, Oregon example

USGS Publications Warehouse

Loveland, Thomas R.; Johnson, Gary E.

1981-01-01

The U. S. Geological Survey's Earth Resources Observations Systems Data Center, in cooperation with the U.S. Army Corps of Engineers, Portland District, developed and tested techniques that used remotely sensed and other spatial data in predictive models to evaluate irrigation agriculture in the Umatilla River Basin of north-central Oregon. Landsat data and 1:24,000-scale aerial photographs were initially used to map he expansion of irrigate from 1973 to 1979 and to identify crops under irrigation in 1979. The crop data were then used with historical water requirement figures and digital topographic and hydrographic data to estimate water and power use for the 1979 irrigation season. The final project task involved production of a composite map of land suitability for irrigation development based on land cover (from Landsat), land-ownership, soil irrigability, slope gradient, and potential energy costs. The methods and data used in the study demonstrated the flexibility of remotely sensed and other spatial data as input for predictive models. When combined, they provided useful answers to complex questions facing resource managers.

Perioperative antimicrobial prophylaxis in neurosurgery: clinical trial of systemic flomoxef administration and saline containing gentamicin for irrigation.

PubMed

Yamamoto, M; Jimbo, M; Ide, M; Tanaka, N; Umebara, Y; Hagiwara, S

1996-06-01

The efficacy of a new protocol consisting of a prophylactic antibiotic regimen of peri- and postoperative intravenous administration of flomoxef and irrigation of the operative field with saline containing gentamicin was assessed by comparing infection rates in two consecutive series of patients who underwent neurosurgical procedures. Group A received postoperative flomoxef administration, with saline containing no antibiotics for irrigation, from July 1988 to December 1989. Group B received the new protocol from January 1990 to December 1991. For further evaluation, this protocol was continued in most patients who underwent surgery from January 1992 through December 1993 (Group C). Only adult or adolescent patients who underwent clean neurosurgical procedures were included. The number of patients and procedures in each group were: 76 patients (97 procedures) in Group A, 103 (133) in Group B, and 107 (137) in Group C. There were no significant differences between Groups A and B in age, sex, clinical category, coexistent disease, clinical outcome, surgical procedures, general anesthesia, emergency operation, steroid administration, and the timing (season), duration, and frequency of surgery. Meningitis developed in three patients and subcutaneous infection in one in Group A. None of the patients in Group B experienced postoperative infection. This difference in infection rates (4.1% vs. 0%) was statistically significant (p = 0.0305). Furthermore, no postoperative infections developed in the Group C patients. The most appropriate interval for multiple dose administration was determined by analyzing intraoperative time-related changes in the serum flomoxef concentration during surgery in 21 recent patients. Serum flomoxef concentrations fell below therapeutic levels (3.0 micrograms/ml) by the 6th post-administration hour in 70% of patients. We conclude that this antibiotic regimen significantly reduces the postoperative infection rate following neurosurgical procedures. Multiple dose administration of flomoxef is recommended when the duration of surgery is 6 hours or more.

A Real-time Irrigation Forecasting System in Jiefangzha Irrigation District, China

NASA Astrophysics Data System (ADS)

Cong, Z.

2015-12-01

In order to improve the irrigation efficiency, we need to know when and how much to irrigate in real time. If we know the soil moisture content at this time, we can forecast the soil moisture content in the next days based on the rainfall forecasting and the crop evapotranspiration forecasting. Then the irrigation should be considered when the forecasting soil moisture content reaches to a threshold. Jiefangzha Irrigation District, a part of Hetao Irrigation District, is located in Inner Mongolia, China. The irrigated area of this irrigation district is about 140,000 ha mainly planting wheat, maize and sunflower. The annual precipitation is below 200mm, so the irrigation is necessary and the irrigation water comes from the Yellow river. We set up 10 sites with 4 TDR sensors at each site (20cm, 40cm, 60cm and 80cm depth) to monitor the soil moisture content. The weather forecasting data are downloaded from the website of European Centre for Medium-Range Weather Forecasts (ECMWF). The reference evapotranspiration is estimated based on FAO-Blaney-Criddle equation with only the air temperature from ECMWF. Then the crop water requirement is forecasted by the crop coefficient multiplying the reference evapotranspiration. Finally, the soil moisture content is forecasted based on soil water balance with the initial condition is set as the monitoring soil moisture content. When the soil moisture content reaches to a threshold, the irrigation warning will be announced. The irrigation mount can be estimated through three ways: (1) making the soil moisture content be equal to the field capacity; (2) making the soil moisture saturated; or (3) according to the irrigation quota. The forecasting period is 10 days. The system is developed according to B2C model with Java language. All the databases and the data analysis are carried out in the server. The customers can log in the website with their own username and password then get the information about the irrigation forecasting and other information about the irrigation. This system can be expanded in other irrigation districts. In future, it is even possible to upgrade the system for the mobile user.

Antibacterial Efficacy of a New Sonic Irrigation Device for Root Canal Disinfection.

PubMed

Neuhaus, Klaus W; Liebi, Melanie; Stauffacher, Simone; Eick, Sigrun; Lussi, Adrian

2016-12-01

Passive ultrasonic irrigation (PUI) is the most widespread method used to activate irrigation solutions. Concerns have been raised that PUI is less effective in curved root canals and is not passive at all. Our aim was to compare a novel passive sonic irrigation (PSI) device (6000 Hz) with PUI and manual irrigation (MI) with respect to their efficiency in removing different endodontic microorganisms from curved and straight root canals. We performed 2 experiments as follows. In a 3-day infection model, we included 8 groups of single or dual microbial species that were rinsed with 0.9% sodium chloride using PSI, PUI, or MI. Colony-forming units (CFUs) were counted after incubation, and log 10 transformations were performed for statistical comparisons. In a 21-d infection model, we tested the same irrigation protocols on 4 groups of microorganisms and used 1.5% sodium hypochlorite as an irrigant. Infection control samples were taken at day 0, 3, 5, and 7 after treatment and were subsequently reincubated. Using sodium chloride as an irrigant, the amount of reduction in CFUs compared with the negative control was approximately 3 log 10 units for PSI at 6000 Hz, 2 log 10 units for PUI, and 1 log 10 unit for MI. PSI reduced the microorganism CFUs significantly better than PUI. Using sodium hypochlorite led to a significant reduction in microorganism CFUs even with MI. After 3 days, compared with MI, microorganism regrowth significantly reduced after PSI and PUI treatment, but in these groups, in at least half of the samples, microorganisms were detectable after 7 days. PSI at 6000 Hz might be at least equal to PUI with respect to reduction of the microbial load in curved and straight root canals. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Comparison of the Antimicrobial Efficacy of Octenidine Dihydrochloride and Chlorhexidine with and Without Passive Ultrasonic Irrigation - An Invitro Study

PubMed Central

Cherian, Bastin; Manjunath, Mysore Krishnaswamy

2016-01-01

Introduction Elimination of microorganisms from infected root canals is a complicated task. Numerous measures have been described to reduce the microbial load in the root canal system, including the use of various instrumentation techniques, irrigation regimens and intracanal medicaments. The drawbacks of few commonly used irrigants include toxic and harmful side effects, microbial resistance to antimicrobial agents and staining. Hence there is a need for alternative agents which are nontoxic, effective and safe. Aim To compare and evaluate antimicrobial effects of 2% Chlorhexidine (CHX) versus 0.1% Octenidine Dihydrochloride (OCT) as root canal irrigant with and without passive ultrasonic irrigation against Enterococcus faecalis (E. faecalis) in vitro and to evaluate the depth of penetration of irrigant solution into the dentinal tubules at the junction of middle and apical third. Materials and Methods Forty eight freshly extracted, single rooted human mandibular premolars were decoronated and root specimen standardized to 14mm. Biofilm of E. faecalis (strain ATCC 29212) was grown for seven days and the specimens were divided into four groups (n=12) based on irrigation protocol : Group I- Conventional Syringe Irrigation (CSI) with 2% CHX, Group II- CSI + 0.1% OCT, Group III-Passive Ultrasonic Irrigation (PUI) + 2% CHX and Group IV- PUI+ 0.1% OCT. Dentin shavings were collected at two depths (200μm and 400μm) and total number of colony forming units were determined. The data were statistically analyzed using ANOVA, Scheffes multiple comparison of means and paired t-test (p<0.05). Results Group III and IV (PUI) showed significant difference compared to Group I and II (CSI) both at 200μm and 400μm (p=0.000). For Group III and Group IV no significant differences were found at 200μm and 400μm (p=1.000 and 0.363 respectively), however significant difference was found between data at 200μm and 400μm for all the four groups (p=0.000). Conclusion Octenidine (0.1%) was more effective than 2% Chlorhexidine against E. faecalis both at 200μm and 400μm. Passive ultrasonic irrigation proved to enhance the antimicrobial action of the irrigants. PMID:27504415

Comparison of the in vivo antimicrobial effectiveness of sodium hypochlorite and chlorhexidine used as root canal irrigants: a molecular microbiology study.

PubMed

Rôças, Isabela N; Siqueira, José F

2011-02-01

The purpose of this clinical study was to compare the antimicrobial effects of 2.5% sodium hypochlorite (NaOCl) and 0.12% chlorhexidine digluconate (CHX) when used as irrigants during treatment of teeth with apical periodontitis. Forty-seven single-rooted single-canal teeth with necrotic pulps and asymptomatic apical periodontitis were selected for this study according to stringent inclusion/exclusion criteria. Bacterial samples were taken at the baseline (S1) and after (S2) chemomechanical preparation using 2.5% NaOCl (n = 30) or 0.12% CHX (n = 17) as the irrigant. Bacterial, archaeal, and fungal presence was evaluated by broad-range polymerase chain reaction (PCR), whereas bacterial identifications were performed by a closed-ended reverse-capture checkerboard approach targeting 28 candidate endodontic pathogens. All S1 samples were PCR positive for bacterial presence but negative for both archaea and fungi. Both NaOCl- and CHX-based protocols were significantly effective in reducing the bacterial levels and number of taxa. No significant differences were observed between them in all tested parameters including the incidence of negative PCR results in S2 (40% for NaOCl vs 47% for CHX, p = 0.8), reduction in the number of taxa per canal (p = 0.3), and reduction in the bacterial levels (p = 0.07). The most prevalent taxa in S2 samples from the NaOCl group were Propionibacterium acnes, Streptococcus species, Porphyromonas endodontalis, and Selenomonas sputigena. In the CHX group, the most prevalent taxa in S2 were Dialister invisus, Actinomyces israelii, Prevotella baroniae, Propionibacterium acidifaciens, and Streptococcus species. Treatment protocols using irrigation with either NaOCl or CHX succeeded in significantly reducing the the number of bacterial taxa and their levels in infected root canals, with no significant difference between these substances. Copyright © 2011 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

In Vivo Intracanal Temperature Evolution during Endodontic Treatment after the Injection of Room Temperature or Preheated Sodium Hypochlorite.

PubMed

de Hemptinne, Ferdinand; Slaus, Gunter; Vandendael, Mathieu; Jacquet, Wolfgang; De Moor, Roeland J; Bottenberg, Peter

2015-07-01

Heating a sodium hypochlorite solution improves its effectiveness. The aim of this study was to measure the in vivo temperature changes of sodium hypochlorite solutions that were initially preheated to 66°C or at room temperature inside root canals during routine irrigation. Thirty-five root canals were prepared to ISO size 40 with 4% taper. A type K (nickel-chromium-nickel) thermocouple microprobe (Testo NV, Ternat, Belgium) was positioned within 3 mm of the working length to measure the temperature at 1-second intervals. In each canal, 2 test protocols were evaluated in a randomized order with 3% sodium hypochlorite solutions: (1) preheated to 66°C and (2) at room temperature. The temperature measurements began 5 seconds before the 25 seconds of irrigant injections and continued for 240 seconds. This resulted in 270 data points for each protocol. The temperature of the irrigant at room temperature increased from the initial intracanal temperature after injection of 20.7°C (±1.2°C) to 30.9°C (±1.3°C) in 10 seconds and to 35°C (±0.9°C) after 240 seconds. The temperature of the preheated to 66°C solution decreased from 56.4°C (±2.7°C) to 45.4°C (±3.0°C) after 5 seconds, reached 37°C (±0.9°C) after 60 seconds, and reached 35.7°C (±0.8°C) after 240 seconds. The original temperatures of the sodium hypochlorite solutions were buffered inside the root canal and tended to rapidly evolve to equilibrium. The findings of this study contribute to an improved understanding of the thermodynamic behaviors of irrigant solutions inside root canals in vivo. Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Water Depletion Threatens Agriculture

NASA Astrophysics Data System (ADS)

Brauman, K. A.; Richter, B. D.; Postel, S.; Floerke, M.; Malsy, M.

2014-12-01

Irrigated agriculture is the human activity that has by far the largest impact on water, constituting 85% of global water consumption and 67% of global water withdrawals. Much of this water use occurs in places where water depletion, the ratio of water consumption to water availability, exceeds 75% for at least one month of the year. Although only 17% of global watershed area experiences depletion at this level or more, nearly 30% of total cropland and 60% of irrigated cropland are found in these depleted watersheds. Staple crops are particularly at risk, with 75% of global irrigated wheat production and 65% of irrigated maize production found in watersheds that are at least seasonally depleted. Of importance to textile production, 75% of cotton production occurs in the same watersheds. For crop production in depleted watersheds, we find that one half to two-thirds of production occurs in watersheds that have not just seasonal but annual water shortages, suggesting that re-distributing water supply over the course of the year cannot be an effective solution to shortage. We explore the degree to which irrigated production in depleted watersheds reflects limitations in supply, a byproduct of the need for irrigation in perennially or seasonally dry landscapes, and identify heavy irrigation consumption that leads to watershed depletion in more humid climates. For watersheds that are not depleted, we evaluate the potential impact of an increase in irrigated production. Finally, we evaluate the benefits of irrigated agriculture in depleted and non-depleted watersheds, quantifying the fraction of irrigated production going to food production, animal feed, and biofuels.

Evaluation of Irrigation Water Use Efficiency and Water-saving in the Middle Oasis of Heihe River Basin Using a Distributed Agro-hydrological Model

NASA Astrophysics Data System (ADS)

Jiang, Y.; Huang, G., Sr.; Xu, X.; Huang, Q.; Huo, Z.

2015-12-01

Severe water scarcity and unreasonable allocation are threatening the eco-environment in the Heihe River basin (HRB), an arid and semi-arid watershed in Northwest China. The water use in the middle oasis accounts for about 70% of the total water use in the HRB, in which over 85% are consumed by irrigated agriculture. Thus the regional assessment and improvement of irrigation water use are quite essential for water-saving and eco-environmental sustainability. This paper applied a distributed agro-hydrological model (SWAP-EPIC) integrated with ArcGIS to investigate the irrigation water use efficiency (WUE) in the middle oasis. The detailed distributed data in 2012, including soil properties, irrigation schedules, crop pattern and calendar, were collected and used in the regional simulation. The spatial-temporal distribution of LAI and evapotranspiration (ETa) from remote sensing were used as observations to calibrate the model. Results showed that the simulation data was in a good agreement with the observation one. The relative WUE (i.e. divided by the mean value) ranged from 0.77 to 1.33 in different canal command areas. Large spatial variations of WUE were mainly caused by the non-uniform distribution of irrigation water. The present irrigation performance was poor, and only 50% of total irrigation amount was finally utilized through evapotranspiration in the whole district. While nearly 24% of the irrigation water were lost through field deep percolation and 26% were wasted in canal conveyance. Further analysis of water-saving scenarios was conducted through applying the improved irrigation schedule for each crop-soil unites and increasing the canal conveyance efficiency. Prediction showed that 15% of total irrigation amount can be saved without reduction of crop yield.

Is current irrigation sustainable in the United States? An integrated assessment of climate change impact on water resources and irrigated crop yields

DOE PAGES

Blanc, Elodie; Caron, Justin; Fant, Charles; ...

2017-06-27

While climate change impacts on crop yields has been extensively studied, estimating the impact of water shortages on irrigated crop yields is challenging because the water resources management system is complex. To investigate this issue, we integrate a crop yield reduction module and a water resources model into the MIT Integrated Global System Modeling framework, an integrated assessment model linking a global economic model to an Earth system model. We assess the effects of climate and socioeconomic changes on water availability for irrigation in the U.S. as well as subsequent impacts on crop yields by 2050, while accounting for climatemore » change projection uncertainty. We find that climate and socioeconomic changes will increase water shortages and strongly reduce irrigated yields for specific crops (i.e., cotton and forage), or in specific regions (i.e., the Southwest) where irrigation is not sustainable. Crop modeling studies that do not represent changes in irrigation availability can thus be misleading. Yet, since the most water-stressed basins represent a relatively small share of U.S. irrigated areas, the overall reduction in U.S. crop yields is small. The response of crop yields to climate change and water stress also suggests that some level of adaptation will be feasible, like relocating croplands to regions with sustainable irrigation or switching to less irrigation intensive crops. Finally, additional simulations show that greenhouse gas (GHG) mitigation can alleviate the effect of water stress on irrigated crop yields, enough to offset the reduced CO 2 fertilization effect compared to an unconstrained GHG emission scenario.« less

Is current irrigation sustainable in the United States? An integrated assessment of climate change impact on water resources and irrigated crop yields

DOE Office of Scientific and Technical Information (OSTI.GOV)

Blanc, Elodie; Caron, Justin; Fant, Charles

While climate change impacts on crop yields has been extensively studied, estimating the impact of water shortages on irrigated crop yields is challenging because the water resources management system is complex. To investigate this issue, we integrate a crop yield reduction module and a water resources model into the MIT Integrated Global System Modeling framework, an integrated assessment model linking a global economic model to an Earth system model. We assess the effects of climate and socioeconomic changes on water availability for irrigation in the U.S. as well as subsequent impacts on crop yields by 2050, while accounting for climatemore » change projection uncertainty. We find that climate and socioeconomic changes will increase water shortages and strongly reduce irrigated yields for specific crops (i.e., cotton and forage), or in specific regions (i.e., the Southwest) where irrigation is not sustainable. Crop modeling studies that do not represent changes in irrigation availability can thus be misleading. Yet, since the most water-stressed basins represent a relatively small share of U.S. irrigated areas, the overall reduction in U.S. crop yields is small. The response of crop yields to climate change and water stress also suggests that some level of adaptation will be feasible, like relocating croplands to regions with sustainable irrigation or switching to less irrigation intensive crops. Finally, additional simulations show that greenhouse gas (GHG) mitigation can alleviate the effect of water stress on irrigated crop yields, enough to offset the reduced CO 2 fertilization effect compared to an unconstrained GHG emission scenario.« less

Phyto-recurrent selection: a tree improvement strategy for selecting genotypes used in phytoremediation

Treesearch

Ronald S., Jr. Zalesny; Edmund O. Bauer

2006-01-01

The success of using Populus and Salix for phytoremediation has prompted further use of leachate as a combination of irrigation and fertilization for the trees. A common protocol for such efforts has been to utilize a limited number of readily-available genotypes with decades of deployment in other applications, such as fiber or...

Performing and updating an inventory of Oregon's expanding irrigated agricultural lands utilizing remote sensing technology

NASA Technical Reports Server (NTRS)

Hall, M. J.

1981-01-01

An inventory technique based upon using remote sensing technology, interpreting both high altitude aerial photography and LANDSAT multispectral scanner imagery, is discussed. It is noted that once the final land use inventory maps of irrigated agricultural lands are available and approximately scaled they may be overlaid directly onto either multispectral scanner or return beam vidicon prints, thereby providing an inexpensive updating procedure.

Effect of endodontic irrigation with 1% sodium hypochlorite and 17% EDTA on primary teeth: a scanning electron microscope analysis.

PubMed

Ximenes, Marcos; Triches, Thaisa C; Beltrame, Ana Paula C A; Hilgert, Leandro A; Cardoso, Mariane

2013-01-01

This study evaluated the efficacy of 2 final irrigation solutions for removal of the smear layer (SL) from root canals of primary teeth, using scanning electron microscope (SEM) analysis. Thirty primary molars were selected and a single operator instrumented the canals. The initial irrigation was done with a 1% sodium hypochlorite (NaOCl) solution. After the preparation, the roots were randomly divided into 3 groups for final irrigation: Group 1, 1% NaOCl (n = 10); Group 2, 17% EDTA + 1% NaOCl (n = 10); and Group 3, 17% EDTA + saline solution (n = 10). The roots were prepared for SEM analysis (magnification 1000X). The photomicrographs were independently analyzed by 2 investigators with SEM experience, attributing scores to each root third in terms of SL removal. Kruskal-Wallis and Mann-Whitney tests revealed that there was no statistical difference between the groups (P = 0.489). However, a statistical difference was found (P < 0.05) in a comparison of root thirds, with the apical third having the worst results. Comparing the thirds within the same group, all canals showed statistical differences between the cervical and apical thirds (P < 0.05). The authors determined that no substance or association of substances were able to completely remove SL.

In vivo antimicrobial efficacy of 6% Morinda citrifolia, Azadirachta indica, and 3% sodium hypochlorite as root canal irrigants.

PubMed

Podar, Rajesh; Kulkarni, Gaurav P; Dadu, Shifali S; Singh, Shraddha; Singh, Shishir H

2015-01-01

To evaluate and compare the antimicrobial efficacy of 6% Morinda citrifolia, Azadirachta indica, and 3% sodium hypochlorite (NaOCl) as root canal irrigants. Thirty nonvital maxillary anteriors were randomly assigned to one of the three groups corresponding to the irrigant to be tested; 6% Morinda citrifolia juice (MCJ) (n = 10), A. indica (n = 10) and 3% NaOCl (n = 10). After the root canal access opening a root canal culture sample was taken with two paper points and cultured under aerobic and anaerobic conditions. Cleaning and shaping were completed with irrigation by 10 mL of respective irrigants and 5 mL of final rinse. The patients were recalled after 3 days and canals were rinsed again with 5 mL of the test irrigants. This was followed by obtaining a posttreatment root canal culture sample and culturing and analyzed by counting the colony forming units (CFUs). Six percentage MCJ, A. indica, and 3% NaOCl showed a significant reduction (P < 0.05) in the mean CFU counts for aerobic and anaerobic bacteria between baseline and 3 days. There was no difference in the antimicrobial efficacy of 6% M. citrifolia, A. indica, and 3% NaOCl as root canal irrigants.

Apical extrusion of debris and irrigants using ProTaper hand, M-two rotary and WaveOne single file reciprocating system: An ex vivo study.

PubMed

Singh, Abhishek; Arunagiri, Doraiswamy; Pushpa, Shankarappa; Sawhny, Asheesh; Misra, Abhinav; Khetan, Kirti

2015-01-01

The purpose of this ex vivo study was to evaluate and compare the weight of debris and volume of irrigant extruded apically from teeth using different preparation techniques. Thirty extracted human mandibular premolars with single canals and similar lengths were instrumented using hand ProTaper F2 (25, 0.08; Dentsply Maillefer, Ballaigues, Switzerland), M-two (25, 0.06; VDW, Munich, Germany) and WaveOne Primary (25, 0.08; Dentsply Maillefer, Ballaigues, Switzerland). Debris and irrigant extruded during instrumentation were collected into preweighed Eppendorf tubes. The volume of the irrigant was measured, and then the tubes were stored in an incubator at 70°C for 2 days. The Eppendorf tubes were weighed to obtain the final weight when the extruded debris was included. Three consecutive weights were obtained for each tube. Data were statistically analyzed by one-way analysis of variance and Student's t-test. There were no statistically significant differences among the groups. The WaveOne reciprocating system showed the maximum amount of apical extrusion of debris and irrigant among all the groups. The least amount of debris and irrigant was observed in ProTaper hand instrument (P > 0.05). All instrumentation techniques were associated with debris and irrigant extrusion.

Marginal cost curves for water footprint reduction in irrigated agriculture: guiding a cost-effective reduction of crop water consumption to a permit or benchmark level

NASA Astrophysics Data System (ADS)

Chukalla, Abebe D.; Krol, Maarten S.; Hoekstra, Arjen Y.

2017-07-01

Reducing the water footprint (WF) of the process of growing irrigated crops is an indispensable element in water management, particularly in water-scarce areas. To achieve this, information on marginal cost curves (MCCs) that rank management packages according to their cost-effectiveness to reduce the WF need to support the decision making. MCCs enable the estimation of the cost associated with a certain WF reduction target, e.g. towards a given WF permit (expressed in m3  ha-1 per season) or to a certain WF benchmark (expressed in m3  t-1 of crop). This paper aims to develop MCCs for WF reduction for a range of selected cases. AquaCrop, a soil-water-balance and crop-growth model, is used to estimate the effect of different management packages on evapotranspiration and crop yield and thus the WF of crop production. A management package is defined as a specific combination of management practices: irrigation technique (furrow, sprinkler, drip or subsurface drip); irrigation strategy (full or deficit irrigation); and mulching practice (no, organic or synthetic mulching). The annual average cost for each management package is estimated as the annualized capital cost plus the annual costs of maintenance and operations (i.e. costs of water, energy and labour). Different cases are considered, including three crops (maize, tomato and potato); four types of environment (humid in UK, sub-humid in Italy, semi-arid in Spain and arid in Israel); three hydrologic years (wet, normal and dry years) and three soil types (loam, silty clay loam and sandy loam). For each crop, alternative WF reduction pathways were developed, after which the most cost-effective pathway was selected to develop the MCC for WF reduction. When aiming at WF reduction one can best improve the irrigation strategy first, next the mulching practice and finally the irrigation technique. Moving from a full to deficit irrigation strategy is found to be a no-regret measure: it reduces the WF by reducing water consumption at negligible yield reduction while reducing the cost for irrigation water and the associated costs for energy and labour. Next, moving from no to organic mulching has a high cost-effectiveness, reducing the WF significantly at low cost. Finally, changing from sprinkler or furrow to drip or subsurface drip irrigation reduces the WF, but at a significant cost.

Thoracic irrigation prevents retained hemothorax: a pilot study.

PubMed

Kugler, Nathan W; Carver, Thomas W; Paul, Jasmeet S

2016-05-15

Upward of 20% of patients undergoing thoracostomy tube (TT) placement develop retained hemothorax (HTx) requiring secondary intervention. The aim of this study was to define the rate of secondary intervention in patients undergoing prophylactic thoracic irrigation. A prospective observational trial of 20 patients who underwent thoracic irrigation at the time of TT placement was conducted. Patients with HTx identified on chest x-ray were included. After standard placement of a 36-French TT, the HTx was evacuated using a sterile suction catheter advanced within the TT. Warmed sterile saline was instilled into the chest through the TT followed by suction catheter evacuation. The TT was connected to the sterile drainage atrium and suction applied. TTs were managed in accordance with our standard division protocol. The population was predominantly (70%) male at median age 35 years, median ISS 13, with 55% suffering penetrating trauma. Thirteen (65%) patients underwent TT placement within 6 h of trauma with the remainder within 24 h. Nineteen patients received the full 1000-mL irrigation. The majority demonstrated significant improvement on postprocedure chest x-ray. The secondary intervention rate was 5%. A single patient required VATS on post-trauma day zero for retained HTx. Median TT duration was 5 d with median length of stay of 7 d. No adverse events related to the pleural lavage were noted. Thoracic irrigation at the time of TT placement for traumatic HTx may decrease the rate of retained HTx. Copyright © 2016 Elsevier Inc. All rights reserved.

[Real-time irrigation forecast of cotton mulched with plastic film under drip irrigation based on meteorological date].

PubMed

Shen, Xiao-jun; Sun, Jing-sheng; Li, Ming-si; Zhang, Ji-yang; Wang, Jing-lei; Li, Dong-wei

2015-02-01

It is important to improve the real-time irrigation forecasting precision by predicting real-time water consumption of cotton mulched with plastic film under drip irrigation based on meteorological data and cotton growth status. The model parameters for calculating ET0 based on Hargreaves formula were determined using historical meteorological data from 1953 to 2008 in Shihezi reclamation area. According to the field experimental data of growing season in 2009-2010, the model of computing crop coefficient Kc was established based on accumulated temperature. On the basis of crop water requirement (ET0) and Kc, a real-time irrigation forecast model was finally constructed, and it was verified by the field experimental data in 2011. The results showed that the forecast model had high forecasting precision, and the average absolute values of relative error between the predicted value and measured value were about 3.7%, 2.4% and 1.6% during seedling, squaring and blossom-boll forming stages, respectively. The forecast model could be used to modify the predicted values in time according to the real-time meteorological data and to guide the water management in local film-mulched cotton field under drip irrigation.

Analytical Solution for Optimum Design of Furrow Irrigation Systems

NASA Astrophysics Data System (ADS)

Kiwan, M. E.

1996-05-01

An analytical solution for the optimum design of furrow irrigation systems is derived. The non-linear calculus optimization method is used to formulate a general form for designing the optimum system elements under circumstances of maximizing the water application efficiency of the system during irrigation. Different system bases and constraints are considered in the solution. A full irrigation water depth is considered to be achieved at the tail of the furrow line. The solution is based on neglecting the recession and depletion times after off-irrigation. This assumption is valid in the case of open-end (free gradient) furrow systems rather than closed-end (closed dike) systems. Illustrative examples for different systems are presented and the results are compared with the output obtained using an iterative numerical solution method. The final derived solution is expressed as a function of the furrow length ratio (the furrow length to the water travelling distance). The function of water travelling developed by Reddy et al. is considered for reaching the optimum solution. As practical results from the study, the optimum furrow elements for free gradient systems can be estimated to achieve the maximum application efficiency, i.e. furrow length, water inflow rate and cutoff irrigation time.

Influence of irrigation and obturation techniques on artificial lateral root canal filling capacity.

PubMed

Silva, Emmanuel J; Herrera, Daniel R; Souza-Júnior, Eduardo J; Teixeira, João M

2013-01-01

The aim of this study was to evaluate the influence of two different irrigation protocols on artificial lateral root canal filling capacity using different obturation techniques. Sixty single-root human teeth were used. Two artificial lateral canals were created in the apical third. Root canals were instrumented up to a 45 K-file to the working length. Before each file, root canals were irrigated either with 2 mL of 2.5% NaOCl or 2% chlorhexidine gel with further irrigation with saline solution and 3 mL of 17% EDTA. Specimens were randomly divided into three groups according to the obturation technique: (1) lateral compaction technique; (2) Tagger hybrid technique; and (3) thermoplasticized technique using BeeFill 2 in 1. All groups used AH Plus as the root canal sealer. The specimens were decalcified and cleared in methyl salicylate. The total length of lateral canals was observed under X30 magnification with a stereomicroscope and measured on the buccal and lingual root surfaces using Leica IM50 software. The data were submitted to ANOVA and Tukey test (p < 0.05). Among the obturation techniques, BeeFill 2 in 1 showed deeper penetration into all lateral canals than the lateral compaction or Tagger hybrid techniques (p < 0.05). The lateral compaction group showed the worst results (p < 0.05). Irrigants did not affect the outcome; there was no difference between NaOCl and chlorhexidine when the same obturation technique was used (p > 0.05). Regardless of the irrigant used during endodontic procedures, the thermoplasticized techniques showed higher penetration behavior for filling artificial lateral canals than the lateral compaction technique.

Evaluation of 4 Different Irrigating Systems for Apical Extrusion of Sodium Hypochlorite.

PubMed

Yost, Ross A; Bergeron, Brian E; Kirkpatrick, Timothy C; Roberts, Mark D; Roberts, Howard W; Himel, Van T; Sabey, Kent A

2015-09-01

The aim of this study was to evaluate NaOCl apical extrusion by using negative apical pressure (EndoVac), sonic agitation (EndoActivator), side-vented needle (Max-i-Probe), and photon induced photoacoustic streaming (PIPS 10 mJ and PIPS 20 mJ) laser irrigation in an in vitro gel model. Extracted mandibular and maxillary central incisors (n = 18) were prepared to size 35/.04 and 55/.04, respectively. Teeth were mounted in transparent containers with clear acrylic and suspended in a color-changing pH-sensitive gel, creating a closed system. By using a crossover design, each tooth was sequentially irrigated by using 6% NaOCl with each device following manufacturers' recommendations. Each tooth served as its own control. Pre-irrigation and post-irrigation buccal and proximal view photographs served to measure the longest distance of extrusion and were analyzed with ImageJ software. Mean results were analyzed by using Kruskal-Wallis and Dunn post hoc test (P < .05). There were no significant differences between EndoVac, EndoActivator, and the passive extrusion groups. The EndoVac and EndoActivator groups produced significantly less extrusion than PIPS irrigation. Max-i-Probe extrusion results were more variable than those of EndoActivator but had no significant difference. Across all irrigation systems, there were no significant differences with respect to apical preparation size. Under the in vitro conditions of this study, no difference was found between the 10 mJ and 20 mJ PIPS laser groups. EndoVac demonstrated significantly less potential for apical extrusion than PIPS and Max-i-Probe, whereas apical preparation size did not significantly affect extrusion of irrigant. The potential for apical extrusion of endodontic irrigants should be a consideration when selecting a system for final irrigation. Published by Elsevier Inc.

The Immediate and Delayed Post-Debridement Effects on Tissue Bacterial Wound Counts of Hypochlorous Acid Versus Saline Irrigation in Chronic Wounds.

PubMed

Hiebert, John M; Robson, Martin C

2016-01-01

Introduction: Wound debridement is considered essential in chronic wound management. Hypochlorous acid has been shown to be an effective agent in reducing wound bacterial counts in open wounds. Ultrasound-enabled wound debridement is an effective and efficient method of debridement. This study compared ultrasound irrigation with hypochlorous acid versus saline irrigation for wound debridement on pre- and postoperative wounds and determined regrowth of bacteria over 1 week period of time. Finally, the outcome of definitive wound closure of the clinically clean-appearing wounds was recorded. Methods: Seventeen consenting adult patients with chronic open wounds were randomly selected for study. The patients were randomly divided into the hypochlorous acid irrigation or saline irrigation group. All patients provided pre- and postoperative tissue samples for qualitative and quantitative bacteriology. For the time (7 days) between the debridement procedure and the definitive closure procedure, the wounds were dressed with a silver-impregnated dressing and a hydroconductive dressing. Results : Both types of irrigation in the ultrasonic system initially lowered the bacterial counts by 4 to 6 logs. However, by the time of definitive closure, the saline-irrigated wounds had bacterial counts back up to 10 5 whereas the hypochlorous acid-irrigated wounds remained at 10 2 or fewer. More than 80% of patients in the saline group had postoperative closure failure compared with 25% of patients in the hypochlorous acid group. Conclusions: Hypochlorous acid irrigation with ultrasound debridement reduced bacterial growth in chronic open wounds more efficiently than saline alone. Postoperative wound closure outcomes suggest a remarkable reduction in wound complications after wound debridement using hypochlorous acid irrigation with ultrasound versus saline alone.

In vitro comparison of passive and continuous ultrasonic irrigation in simulated lateral canals of extracted teeth.

PubMed

Castelo-Baz, Pablo; Martín-Biedma, Benjamín; Cantatore, Giuseppe; Ruíz-Piñón, Manuel; Bahillo, José; Rivas-Mundiña, Berta; Varela-Patiño, Purificación

2012-05-01

Complete endodontic system disinfection requires the removal of vital and necrotic pulp tissue, microorganisms, and toxins. The purpose of this study was to compare the effects of 2 ultrasonic irrigation techniques on the penetration of sodium hypochlorite into the main canal and simulated lateral canals of extracted teeth. Two simulated lateral canals each were created 2, 4, and 6 mm from the working length in 60 single-rooted teeth (6 canals/tooth, n = 360). To resemble the clinical situation, a closed system was created in each tooth. The teeth were randomly assigned to 3 experimental irrigation groups: group 1 (n = 20), positive pressure irrigation (PPI); group 2 (n = 20), passive ultrasonic irrigation (PUI); and group 3 (n = 20), continuous ultrasonic irrigation (CUI). Samples were evaluated by direct observation of still images recorded under a dental operating microscope. To examine irrigating solution penetration, 20% Chinese ink (Sanford Rotring GmbH, Hamburg, Germany) was added to a 5% sodium hypochlorite solution and delivered into the root canals. The results showed a significantly higher (P < .05) penetration of irrigant into the lateral canals in the CUI group. PUI and CUI did not differ significantly in solution penetration into the apical thirds of the main canals. The PPI group showed a significantly lower penetration of sodium hypochlorite into the main and lateral canals compared with the CUI and PUI groups. CUI as a final rinse significantly increased the penetration of irrigating solution into simulated lateral canals. Copyright © 2012 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Simulation of Soil Wetting Patterns in Drip and Subsurface Irrigation. Effects in Design and Irrigation Management Variables.

NASA Astrophysics Data System (ADS)

Rodríguez-Sinobas, L.; Gil-Rodríguez, M.; Sánchez, R.; Losada, A.; Castañón, G.; Juana, L.; Laguna, F. V.; Benítez, J.

2010-05-01

Conventional drip irrigation is considered one of the most efficient irrigation systems. Alternatively to traditional surface drip irrigation systems (DI), laterals are deployed underneath the soil surface, as in subsurface drip irrigation (SDI), leading to a higher potential efficiency, which is of especial interest in places where water is a limited source. The design and management of DI and SDI systems involve selection of an appropriate combination of emitter discharge rate and spacing between emitters and the inlet pressure and irrigation time for any given set of soil, crop, and climatic conditions, as well as understanding the wetted zone pattern around the emitter. Likewise, water distribution is affected by soil hydraulic properties, initial water content, emitter discharge, irrigation frequency, evapotranspiration and root characteristics. However, complexity arousing of soil water properties and soil profile characteristics means that these are often not properly considered in the design and management of those systems. A better understanding of the infiltration process around the discharge point source should contribute to increase water use efficiency and thus to reduce the risk of environmental impact of irrigation. In this regard, numerical models have been proved to be a powerful tool to analyze the evolution of the wetting pattern during the distribution and redistribution processes, in order to explore irrigation management strategies, to set up the duration of irrigation, and finally to optimize water use efficiency. Also, irrigation design variables such as emitter spacing and discharge could also be assessed. In this study the suitability of the HYDRUS-2D to simulate infiltration process around an emitter during irrigation of a loamy soil with drip and SDI laterals has been addressed. The model was then applied in order to evaluate the main dimensions of the wetted soil volume surrounding the emitter during irrigation. Irrigation uniformity with DI and SDI laterals were determined by field evaluations at different inlet head pressures. Results were related with estimations made on water distribution within the soil that were simulated taking into account the emitter discharge at different lateral locations, initial soil water content, soil hydraulic properties and time of irrigation. Conclusions highlight the effect of emitter discharge, emitter spacing, and irrigation time on wetting patterns, and thus solute transport, in both drip and subsurface drip irrigation. The effect of emitter depth was also considered in SDI. Some recommendations for the design and management of these irrigation systems are also provided.

Reduction of hard-tissue debris accumulation during rotary root canal instrumentation by etidronic acid in a sodium hypochlorite irrigant.

PubMed

Paqué, Frank; Rechenberg, Dan-Krister; Zehnder, Matthias

2012-05-01

Hard-tissue debris is accumulated during rotary instrumentation. This study investigated to what extent a calcium-complexing agent that has good short-term compatibility with sodium hypochlorite (NaOCl) could reduce debris accumulation when applied in an all-in-one irrigant during root canal instrumentation. Sixty extracted mandibular molars with isthmuses in the mesial root canal system were selected based on prescans using a micro-computed tomography system. Thirty teeth each were randomly assigned to be instrumented with a rotary system and irrigated with either 2.5% NaOCl or 2.5% NaOCl containing 9% (wt/vol) etidronic acid (HEBP). Using a side-vented irrigating tip, 2 mL of irrigant was applied by 1 blinded investigator to the mesial canals after each instrument. Five milliliters of irrigant was applied per canal as the final rinse. Mesial root canal systems were scanned at high resolution before and after treatment, and accumulated hard-tissue debris was calculated as vol% of the original canal anatomy. Values between groups were compared using the Student's t test (α < .05). Irrigation with 2.5% NaOCl resulted in 5.5 ± 3.6 vol% accumulated hard-tissue debris compared with 3.8 ± 1.8 vol% when HEBP was contained in the irrigant (P < .05). A hypochlorite-compatible chelator can reduce but not completely prevent hard-tissue debris accumulation during rotary root canal instrumentation. Copyright © 2012 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Efficacy of sonic and ultrasonic activation for removal of calcium hydroxide from mesial canals of mandibular molars: a microtomographic study.

PubMed

Wiseman, Anne; Cox, Timothy C; Paranjpe, Avina; Flake, Natasha M; Cohenca, Nestor; Johnson, James D

2011-02-01

The purpose of this study was to use micro-computed tomography (micro-CT) scanning to evaluate the efficacy of sonic and passive ultrasonic irrigation (PUI) on calcium hydroxide (Ca[OH](2)) removal and to measure the volume and percentage of Ca(OH)(2) remaining in the root canal system. The root canals of 46 extracted human mandibular molar teeth were prepared with rotary instruments and randomly assigned to two experimental groups (n = 40) as well as positive and negative controls (n = 6). In each experimental group, 20 teeth were assigned to each irrigation protocol, sonic or passive ultrasonic irrigation. All experimental teeth and the positive controls were filled with Ca(OH)(2), whereas the negative control teeth did not receive Ca(OH)(2). All teeth were scanned using micro-CT scanning to determine the dressing volume. After 7 days, the Ca(OH)(2) was removed in the experimental groups using rotary instrumentation only, and the teeth were again scanned using micro-CT scanning to calculate volume and percentage of Ca(OH)(2) removed. Positive control teeth were not subjected to rotary instrumentation. Experimental samples were then irrigated using either sonic or passive ultrasonic and the volume of remaining Ca(OH)(2) was calculated using micro-CT. Remnants of Ca(OH)(2) were found in all experimental groups. No Ca(OH)(2) was found in the negative controls, whereas a mean of 8.7 mm(3) of Ca(OH)(2) was recorded in the positive controls. Rotary plus passive ultrasonic irrigation removed significantly more Ca(OH)(2) (85.7%) than rotary plus sonic irrigation (71.5%) (p < 0.001). The combination of rotary instrumentation and passive ultrasonic activation for 3 periods of 20 seconds results in significantly lower amounts of Ca(OH)(2) remnants in the canal compared with sonic irrigation. Copyright © 2011. Published by Elsevier Inc.

From methylene blue (methylthionine chloride) to Al-Ghorab procedure: the therapy of priapism (our experience).

PubMed

Passavanti, Giandomenico; Bragaglia, Alessandro; Paolini, Riccardo

2009-12-01

The better knowledge concerning the anatomo-physiology of erection has brought important changes to the management of priapism. We experimented with a staged therapeutic protocol forthis condition. 17 patients, aged from 27 to 71 (mean age 43) were treated for ischemic priapism; the pathogenesis was idiopathic in 9 cases, in 4 cases secondary to intracavernous injection (IcI) of PGE1, in 2 cases to papaverine Icd, in 1 case to haemolympho-pathy and in another patient to treatement with heparin. Cavernous PO2, PCO2 and pH were checked. All patients underwent removal of 100 cc of blood, irrigation with NaHCO3 solution of the cavernous corpora and Methylen blue (MB) IcI 10 mg every 5 minutes 10 times, repeated twice. From 3 to 6 hours from the beginning of therapy, detumescence was achieved in 10 cases. In 5 cases the priapism persisted and we administered adrenaline 20 pg every 5-10 minutes: 2 cases had detumescence respectively in 5 and 7 hours whereas in the patient with leukaemia the erection persisted and we desisted from further therapy; in 2 other cases the erection persisted and we did a distal cavernosum-glans shunt and the detumescence a was achieved in 30 and 58 hours respectively. In the last 2 cases, before adrenaline we administered an IcI of ethylephrine 5 mg every 5 minutes for 4-5 times but finally we had to perform a shunt. In all cases, during the treatment, and during the following 6-8 hours, we administered 200 mg of MB intravenous. The introduction of oral drugs has changed the epidemiology of priapism. A better knowledge of the molecular mechanisms that govern the cavernous contraction and myorelaxation has allowed us to use adrenergic drugs and also the MB. This staged therapeutic protocol goes from a less invasive therapy (irrigation with NaHCO3, MB, ethylephrine, adrenaline) to a surgical procedure which must not be delayed and this progression could allow a reduction in the collateral effects.

Economic risk assessment of drought impacts on irrigated agriculture

NASA Astrophysics Data System (ADS)

Lopez-Nicolas, A.; Pulido-Velazquez, M.; Macian-Sorribes, H.

2017-07-01

In this paper we present an innovative framework for an economic risk analysis of drought impacts on irrigated agriculture. It consists on the integration of three components: stochastic time series modelling for prediction of inflows and future reservoir storages at the beginning of the irrigation season; statistical regression for the evaluation of water deliveries based on projected inflows and storages; and econometric modelling for economic assessment of the production value of agriculture based on irrigation water deliveries and crop prices. Therefore, the effect of the price volatility can be isolated from the losses due to water scarcity in the assessment of the drought impacts. Monte Carlo simulations are applied to generate probability functions of inflows, which are translated into probabilities of storages, deliveries, and finally, production value of agriculture. The framework also allows the assessment of the value of mitigation measures as reduction of economic losses during droughts. The approach was applied to the Jucar river basin, a complex system affected by multiannual severe droughts, with irrigated agriculture as the main consumptive demand. Probability distributions of deliveries and production value were obtained for each irrigation season. In the majority of the irrigation districts, drought causes a significant economic impact. The increase of crop prices can partially offset the losses from the reduction of production due to water scarcity in some districts. Emergency wells contribute to mitigating the droughts' impacts on the Jucar river system.

Debris remaining in the apical third of root canals after chemomechanical preparation by using sodium hypochlorite and glyde: an in vivo study.

PubMed

Cruz, Alvaro; Vera, Jorge; Gascón, Gerardo; Palafox-Sánchez, Claudia A; Amezcua, Octavio; Mercado, Gabriela

2014-09-01

During chemomechanical instrumentation, several liquid or paste substances are used to ease the action of the files and to eliminate debris and the smear layer. The aim of this study was to evaluate whether the use of a paste containing EDTA during cleaning and shaping of the root canal helps to eliminate debris. Twenty root canals in dog teeth were instrumented by a crown-down technique by using nickel-titanium rotary files. In 10 root canals (group A), sodium hypochlorite was used during instrumentation, followed by a final irrigation with 17% liquid EDTA. In another 10 canals (group B), sodium hypochlorite was again used as the irrigating solution, but Glyde File Prep paste was used with every instrument, and a final irrigation with EDTA was also carried out. Two additional teeth were used as positive and 2 as negative controls. The jaws were prepared for histologic evaluation. In group A where Glyde was not used during cleaning and shaping, little or no debris was found in the apical third of the instrumented root canals; however; in group B in which Glyde File Prep paste was used during chemomechanical instrumentation, moderate to high accumulation of debris was observed in the apical third. The use of Glyde File Prep paste during rotary mechanical instrumentation favors the accumulation of debris in the apical third of the root canals. Irrigation with NaOCl and a final flush with EDTA by means of a small-gauge needle with simultaneous aspiration led to less accumulation of debris than in the Glyde File Prep group (P < .05). Copyright © 2014 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Wettability of root canal sealers on intraradicular dentine treated with different irrigating solutions.

PubMed

Ballal, Nidambur Vasudev; Tweeny, Adlyn; Khechen, Khaled; Prabhu, K Narayan; Satyanarayan; Tay, Franklin R

2013-06-01

The aim of this in vitro study was to evaluate the wettability of AH Plus and ThermaSeal Plus sealers on intraradicular dentine treated with different irrigating solutions. Fifty anterior teeth were decoronated and split longitudinally. Each root half was divided into 5 groups (n=10). Group I: 5mL of 2.5% NaOCl+QMix. Group II: 5mL of 2.5% NaOCl+17% EDTA. Group III: 5mL of 2.5% NaOCl+7% maleic acid. Group IV: 5mL of 2.5% NaOCl. Group V: 5mL of distilled water. Irrigation regimens were performed for 1min. Each specimen was placed inside a Dynamic Contact Angle Analyser. A controlled-volume droplet of sealer was placed on each specimen and the static contact angle was analysed. The contact angle made by both sealers with EDTA-irrigated dentine was significantly larger when compared to the other irrigants (P<0.05). For ThermaSeal Plus, contact angles produced on maleic acid-, NaOCl- and distilled water-irrigated dentine were not significantly different, but were all significantly larger than the contact angle produced on QMix-irrigated dentine (P<0.05). For AH Plus, contact angles produced on NaOCl- and distilled water-irrigated dentine were not significantly different, but were significantly larger than those made by maleic acid and QMix. When used as a final irrigant, QMix favours the wetting of root canal dentine by both AH Plus and ThermaSeal Plus sealers. Maleic acid shows a promising result when compared to EDTA and NaOCl. Wettability of both sealers is the worst on EDTA-irrigated dentine. The present study highlights the effect of newer endodontic irrigating solutions on the wettability of sealers on to the root canal dentine, which is required for obtaining good obturation seal. Copyright © 2013 Elsevier Ltd. All rights reserved.

Multidecadal Land Cover Change in the Los Angeles Basin and its Water Consumption Implications

NASA Astrophysics Data System (ADS)

Colombi, N. K.; Lettenmaier, D. P.; Marlier, M. E.

2017-12-01

Urban irrigation is an important component of the hydrologic cycle in areas with arid and semi-arid climates. In Los Angeles, outdoor irrigation has the largest potential for water conservation. However, there are significant uncertainties in predicting and quantifying irrigated water use due to unavailability of crucial landcover data. Irrigated vegetation must first be identified and mapped before irrigated water use can be modeled, and steps can be taken towards conservation. We utilized Landsat data at 30m spatial resolution from 1985 to present to quantify temporal dynamics of vegetation cover on a seasonal basis in the Los Angeles Basin based on the Normalized Difference Vegetation Index (NDVI). Previous vegetation surveys have estimated tree cover and other vegetation types as isolated "snapshots", but are of limited use in monitoring fine-scale temporal variations, and their implications for municipal water consumption in particular. When the temporal resolution of images is low, it becomes more difficult to distinguish between natural, as contrasted with irrigated, vegetation. Our work therefore should provide a better basis for identifying irrigated vegetation. In addition, we quantified NDVI changes within specific land cover classifications including, but not limited to, grassland, shrub, and developed land classes. These results will be useful in comparing natural and irrigated vegetation within urban and partially urban areas. They will also help us to understand relationships between NDVI and irrigated water use at fine temporal resolutions. Finally, we have created land cover change maps that allow us to examine the impact of historical urban ecosystem changes on the water balance of the Los Angeles Basin (LAB) over the last 30 years. Understanding historical changes is a first step in determining the most practical ways of improving water use sustainability in the Los Angeles urban area.

Impact of climate change on irrigation management for olive orchards at southern Spain

NASA Astrophysics Data System (ADS)

Lorite, Ignacio; Gabaldón-Leal, Clara; Santos, Cristina; Belaj, Angjelina; de la Rosa, Raul; Leon, Lorenzo; Ruiz-Ramos, Margarita

2017-04-01

The irrigation management for olive orchards under future weather conditions requires the development of advanced tools for considering specific physiological and phenological components affected by the foreseen changes in climate and atmospheric [CO2]. In this study a new simulation model named AdaptaOlive has been considered to develop controlled deficit irrigation and full irrigation scheduling for the traditional olive orchards located in Andalusia region (southern Spain) under the projected climate generated by an ensemble of 11 climate models from the ENSEMBLES European project corresponding to the SRES A1B scenario. Irrigation requirements, irrigation water productivity (IWP) and net margin (NM) were evaluated for three periods (baseline, near future and far future) and three irrigation strategies (rainfed, RF, controlled deficit irrigation, CDI, and full irrigation, FI). For irrigation requirements, a very limited average increase for far future compared with baseline period was found (2.6 and 1.3%, for CDI and FI, respectively). Equally, when IWP was analyzed, significant increases were identified for both irrigation strategies (77.4 and 72.2%, for CDI and FI, respectively) due to the high simulated increase in yield. Finally, when net margin was analyzed, the irrigation water cost had a key significance. For low water costs FI provided higher net margin values than for CDI. However, for high water costs (expected in the future due to the foreseen reduction in rainfall and the increase of the competence for the available water resources), net margin is reduced significantly, generating a very elevated number of years with negative net margin. All the described results are affected by a high level of uncertainty as the projections from the ensemble of 11 climate models show large spread. Thus, for a representative location within Andalusia region as Baeza, a reduction of irrigation requirements under full irrigation strategy was found for the ensemble mean (equal to 0.5%). However, when the individual projections from the 11 climate models were considered the variation of irrigation requirements for far future compared with baseline period ranged from increases of 8.5% to reductions of 10.7%. This fact demonstrates the necessity to consider ensembles of climate models for identifying averaged impacts and the range of variability of these impacts, quantifying the uncertainty in the estimates related with water management in the future. The study concludes that the promotion of controlled deficit irrigation strategies is an excellent adaptation strategy. However, this strategy must be supported with the enhance of farmers' training by the implementation of local or regional irrigation advisory services.

A framework for developing research protocols for evaluation of microbial hazards and controls during production that pertain to the quality of agricultural water contacting fresh produce that may be consumed raw

USDA-ARS?s Scientific Manuscript database

Agricultural water may contact fresh produce during irrigation and/or when crop protection sprays (e.g., cooling to prevent sunburn, frost protection, and agrochemical mixtures) are applied. This document provides a framework for designing research studies that would add to our understanding of preh...

Study of the effect of vintage, maturity degree, and irrigation on the amino acid and biogenic amine content of a white wine from the Verdejo variety.

PubMed

Ortega-Heras, Miriam; Pérez-Magariño, Silvia; Del-Villar-Garrachón, Vanesa; González-Huerta, Carlos; Moro Gonzalez, Luis Carlos; Guadarrama Rodríguez, Alberto; Villanueva Sanchez, Sonia; Gallo González, Rubén; Martín de la Helguera, Sara

2014-08-01

The aim of this study was to determine the effect of three factors directly related to the amino acid content of grapes and their interaction. These three factors were vintage, maturity degree and irrigation. The evolution of amino acid was also assessed during the winemaking along with the effect of maturity and irrigation on the biogenic amine formation. The grapes used for this study were of the Verdejo variety. The results indicated that there was a strong vintage effect on amino acid content in grapes, which seemed to be clearly related to climatic conditions. The effect of maturity on amino acid content depended on vintage, irrigation and the amino acid itself although it was observed that irrigation caused the increase of most amino acids present in the berry. Irrigation did not affect the evolution of nitrogen compounds during the alcoholic fermentation process but the maturity degree in some of the amino acids tested did so. No direct relationship could be established between irrigation or maturity degree and biogenic amines. However, it should be noted that the biogenic amine content was very low. Vintage has a strong effect on the amino acid content in grapes which appears to be related to weather conditions. No direct relationship has been found between irrigation or maturity degree and biogenic amines content. Furthermore, it is noted that biogenic amine content found in final wines was very low. © 2013 Society of Chemical Industry.

Improving irrigation and groundwater parameterizations in the Community Land Model (CLM) using in-situ observations and satellite data

NASA Astrophysics Data System (ADS)

Felfelani, F.; Pokhrel, Y. N.

2017-12-01

In this study, we use in-situ observations and satellite data of soil moisture and groundwater to improve irrigation and groundwater parameterizations in the version 4.5 of the Community Land Model (CLM). The irrigation application trigger, which is based on the soil moisture deficit mechanism, is enhanced by integrating soil moisture observations and the data from the Soil Moisture Active Passive (SMAP) mission which is available since 2015. Further, we incorporate different irrigation application mechanisms based on schemes used in various other land surface models (LSMs) and carry out a sensitivity analysis using point simulations at two different irrigated sites in Mead, Nebraska where data from the AmeriFlux observational network are available. We then conduct regional simulations over the entire High Plains region and evaluate model results with the available irrigation water use data at the county-scale. Finally, we present results of groundwater simulations by implementing a simple pumping scheme based on our previous studies. Results from the implementation of current irrigation parameterization used in various LSMs show relatively large difference in vertical soil moisture content profile (e.g., 0.2 mm3/mm3) at point scale which is mostly decreased when averaged over relatively large regions (e.g., 0.04 mm3/mm3 in the High Plains region). It is found that original irrigation module in CLM 4.5 tends to overestimate the soil moisture content compared to both point observations and SMAP, and the results from the improved scheme linked with the groundwater pumping scheme show better agreement with the observations.

Effects of Diode Laser, Gaseous Ozone, and Medical Dressings on Enterococcus faecalis Biofilms in the Root Canal Ex Vivo

PubMed Central

Vlassakidis, Alexander; Niepel, Mediha; Hoedke, Daniela; Schulze, Julia; Neumann, Konrad; Moter, Annette; Noetzel, Jörn

2017-01-01

The objective was to compare the antibacterial effects of adjunctive disinfection using diode laser and gaseous ozone compared to the medical dressings calcium hydroxide (Ca(OH)2) and chlorhexidine gel (CHX-Gel) on Enterococcus faecalis biofilms in human root canals ex vivo. Root canals of 180 human extracted teeth were infected by E. faecalis and divided into 3 main groups (G): G1, control; G2, instrumentation and irrigation using 0.9% NaCl; G3, instrumentation and irrigation using 1% NaOCl. In each main group, the following treatments were applied: gaseous ozone, diode laser, and medical dressings of Ca(OH)2 or CHX-Gel for 7 days (n = 15). Reduction of colony forming units (CFUs) inside the root canal of planktons and frequencies of adherent bacteria after treatment were calculated. Bacterial reduction was significantly affected by the irrigation protocol (p < 0.0005) and the disinfection method (p < 0.0005), and a significant interaction between both factors could be observed (p < 0.0005; ANOVA). In G3 (instrumentation using 1% NaOCl), no significant effect of disinfection methods could be demonstrated on planktonic bacteria (p = 0.062; ANOVA) and frequencies of adherent bacteria (p > 0.05; chi-square test). Instrumentation and irrigation using NaOCl combined with ozone or laser application resulted in comparable bacterial reduction on E. faecalis to the application of medical dressings. PMID:28567421

Safety of gentamicin bladder irrigations in complex urological cases.

PubMed

Defoor, William; Ferguson, Denise; Mashni, Susan; Creelman, Lisa; Reeves, Deborah; Minevich, Eugene; Reddy, Pramod; Sheldon, Curtis

2006-05-01

Recurrent urinary tract infections are common in complex pediatric urological cases, particularly those requiring clean intermittent catheterization. At our institution gentamicin bladder irrigations have been used for antimicrobial prophylaxis and to treat symptomatic bacteriuria, particularly when the infection does not involve the upper urinary tract. The purpose of this study was to assess the safety of this therapy. A retrospective study was performed of all children treated with gentamicin bladder irrigations from 1999 to 2004. The dose was 14 mg gentamicin in 30 ml saline instilled via catheter once or twice daily. Serum creatinine and random gentamicin levels were obtained according to a protocol based on risk of gentamicin toxicity. Patient demographics, laboratory results and outcomes were abstracted from the medical records. A total of 80 patients (38 males and 42 females) were identified. Median patient age was 10 years and median duration of treatment was 90 days. No patient had detectable serum gentamicin levels greater than 0.4 mg/dl. Small increases in serum creatinine were seen in 3 patients, all of whom had chronic renal insufficiency. A total of 21 patients (26%) had breakthrough UTIs, of which 5 (24%) were gentamicin resistant. No adverse events were documented. Gentamicin bladder irrigations are a helpful adjunct in the management of complex pediatric urological cases involving recurrent symptomatic bacteriuria. We no longer require intensive laboratory monitoring of low risk patients at our institution.

Clinical value of colonic irrigation in patients with continence disturbances.

PubMed

Briel, J W; Schouten, W R; Vlot, E A; Smits, S; van Kessel, I

1997-07-01

Continence disturbances, especially fecal soiling, are difficult to treat. Irrigation of the distal part of the large bowel might be considered as a nonsurgical alternative for patients with impaired continence. This study is aimed at evaluating the clinical value of colonic irrigation. Thirty-two patients (16 females; median age, 47 (range, 23-72) years) were offered colonic irrigation on an ambulatory basis. Sixteen patients suffered from fecal soiling (Group I), whereas the other 16 patients were treated for fecal incontinence (Group II). Patients were instructed by enterostomal therapists how to use a conventional colostomy irrigation set to obtain sufficient irrigation of the distal part of their large bowel. Patients with continence disturbances during the daytime were instructed to introduce 500 to 1,000 ml of warm (38 degrees C) water within 5 to 10 minutes after they passed their first stool. In addition, they were advised to wait until the urge to defecate was felt. Patients with soiling during overnight sleep were advised to irrigate during the evening. To determine clinical outcome, a detailed questionnaire was used. Median duration of follow-up was 18 months. Ten patients discontinued irrigation within the first month of treatment. Symptoms resolved completely in two patients. They believed that there was no need to continue treatment any longer. Irrigation had no effect in two patients. Despite the fact that symptoms resolved, six patients discontinued treatment because they experienced pain (n = 2) or they considered the irrigation to be too time-consuming (n = 4). Twenty-two patients are still performing irrigations. Most patients irrigated the colon in the morning after the first stool was passed. Time needed for washout varied between 10 and 90 minutes. Frequency of irrigations varied from two times per day to two times per week. In Group I, irrigation was found to be beneficial in 92 percent of patients, whereas 60 percent of patients in Group II considered the treatment as a major improvement to the quality of their lives. If patients who discontinued treatment because of washout-related problems are included in the assessment of final outcome, the success rate is 79 and 38 percent respectively. Patients with fecal soiling benefit more from colonic irrigation than patients with incontinence for liquid or solid stools. If creation of a stoma is considered, especially in patients with intractable and disabling soiling, it might be worthwhile to treat these patients first by colonic irrigation.

Modified protocol including topical minocycline in orabase to manage medication-related osteonecrosis of the jaw cases.

PubMed

Karasneh, Jumana A; Al-Eryani, Kamal; Clark, Glenn T; Sedghizadeh, Parish P

2016-10-01

Management of medication-related osteone-crosis of the jaw (MRONJ) with active infection can be a serious challenge for clinicians. Based on Association of Oral and Maxillofacial Surgeons (AAOMS) recommendations, we have tested a modified treatment protocol using topical minocycline. Five patients diagnosed with stage II or III MRONJ lesions were willing to consent to our protocol. In addition to conventional treatment as suggested by the AAOMS, such as, surgical debridement, chlorhexidine irrigation, and systemic antibiotics, we applied 10% minocycline to the lesions once a week for sustained local antibiotic delivery. All five patients reported pain relief after the first minocycline application. Complete healing occurred in three patients; case three healed completely after the third application, one case continues to improve toward resolution and one withdraws due to other non-relevant medical problem. In this study, we are reporting favorable results using a modified protocol with topical minocycline to treat MRONJ lesions. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Use of Irrigation to Extend the Seeding Window for Final Reclamation at Yucca Mountain, Nevada

DOE Office of Scientific and Technical Information (OSTI.GOV)

TRW Environmental Safety

2000-08-01

The U.S. Department of Energy has implemented a program to investigate the feasibility of various techniques for reclaiming lands disturbed during site characterization at Yucca Mountain. As part of this program, two studies were conducted in 1997 to assess the effects of combinations of seeding date (date that seeds are planted) and supplemental irrigation on densities of native plant species at Yucca Mountain. Study objectives were to (1) determine whether the traditional seeding window (October-December) could be extended through combinations of seeding date and irrigation date, (2) determine which combination of seeding date and irrigation was most successful, and (3)more » assess the effects of irrigation versus natural precipitation on seedling establishment. In the first study, a multi-species seed mix of 16 native species was sown into plots on four dates (12/96, 2/97, 3/97, and 4/97). Irrigation treatments were control (no irrigation) or addition of 80 mm of supplemental water applied over a one month period. Plant densities were sampled in August and again in October, 1997. In the second study, Larrea tridentata and Lycium andersonii, two species that are common at Yucca Mountain, but difficult to establish from seed, were sown together into plots in January and August, 1997. Half the plots were irrigated with approximately 250 mm of water between August 18 and September 11, while the remaining plots received no irrigation (control). Plant densities were sampled in October, 1997. The August census for the multi-species mix study showed irrigated plots that were sown in February, March and April had higher plant densities and more species than plots that were not irrigated. Irrigation had no effect on plant densities on plots that were seeded in December. Plots were used again in October following 18 mm of precipitation in September. Densities of three species, Ambrosia dumosa, Hymenoclea salsola, and L. tridentata, (warm-season species) were lower on irrigated plots sown in December, February, and March, and showed no response to irrigation on plots sown in April. Therefore, early spring irrigation did not facilitate establishment of warm-season species. These results suggest that these species are dependent upon precipitation while temperatures are warm in late summer or fall. However, control plots that were seeded in December had acceptable densities of these species. A more practical approach might be to avoid irrigation costs by seeding in December and waiting for fall precipitation. The remaining species (cool-season species) showed an opposite response to supplemental water with greater densities on irrigated plots sown in February, March, and April, and no response to irrigation on plots sown in December. While these results show that irrigation can extend the seeding window for cool-season species should it be necessary, it was also apparent that if seeds are sown by late December, irrigation is not necessary to achieve acceptable plant densities.« less

A Review of Antibacterial Agents in Endodontic Treatment

PubMed Central

Rahimi, Saeed; Janani, Maryam; Lotfi, Mehrdad; Shahi, Shahriar; Aghbali, Amirala; Vahid Pakdel, Mahdi; Salem Milani, Amin; Ghasemi, Negin

2014-01-01

Microorganisms play a major role in initiation and perpetuation of pulpal and periapical diseases. Therefore, elimination of the microorganisms present in the root canal system is the fundamental objective of endodontic treatment. The use of mechanical debridement, chemical irrigation or other antimicrobial protocols and intra-canal medicaments are critical to attain this goal. The aim of this article was to review the antimicrobial agents and their properties in endodontics. PMID:25031587

One step pulp revascularization treatment of an immature permanent tooth with chronic apical abscess: a case report.

PubMed

Shin, S Y; Albert, J S; Mortman, R E

2009-12-01

To describe a case in which a mandibular right second premolar with a necrotic pulp, sinus tract, periradicular radiolucency and an immature apex underwent revascularization via a single treatment approach. Revascularization procedures have the potential to heal a partially necrotic pulp, which can be beneficial for the continued root development of immature teeth. However, it is not clear which revascularization protocols are the most effective. This case report details the outcome of a successful revascularization procedure on tooth 45 (FDI) in a 12-year-old patient, eliminating the associated periapical pathosis within 19 months. The tooth was treated using coronal root irrigation with 6% NaOCl and 2% chlorhexidine without instrumentation in a single visit. The successful outcome of this case report suggests that this conservative revascularization treatment approach can preserve the vitality of the dental pulp stem cells and create a suitable environment for pulp regeneration, resulting in the completion of root maturation. The noninstrumentation procedure using 6% NaOCl and 2% chlorhexidine coronal irrigation may help preserve the remaining vital dental pulp stem cells believed to be critical for pulp revascularization. A single visit pulp revascularization protocol can be a favourable treatment option for an immature permanent tooth with a partially necrotic pulp.

Selecting and utilizing Populus and Salix for landfill covers: implications for leachate irrigation.

PubMed

Zalesny, Ronald S; Bauer, Edmund O

2007-01-01

The success of using Populus and Salix for phytoremediation has prompted further use of leachate as a combination of irrigation and fertilization for the trees. A common protocol for such efforts has been to utilize a limited number of readily-available genotypes with decades of deployment in other applications, such as fiber or windbreaks. However, it may be possible to increase phytoremediation success with proper genotypic screening and selection, followed by the field establishment of clones that exhibited favorable potential for cleanup of specific contaminants. There is an overwhelming need for testing and subsequent deployment of diverse Populus and Salix genotypes, given current availability of clonal material and the inherent genetic variation among and within these genera. Therefore, we detail phyto-recurrent selection, a method that consists of revising and combining crop and tree improvement protocols to meet the objective of utilizing superior Populus and Salix clones for remediation applications. Although such information is lacking for environmental clean-up technologies, centuries of plant selection success in agronomy, horticulture, and forestry validate the need for similar approaches in phytoremediation. We bridge the gap between these disciplines by describing project development, clone selection, tree establishment, and evaluation of success metrics in the context of their importance to utilizing trees for phytoremediation.

Factors affecting the periapical healing process of endodontically treated teeth.

PubMed

Holland, Roberto; Gomes, João Eduardo; Cintra, Luciano Tavares Angelo; Queiroz, Índia Olinta de Azevedo; Estrela, Carlos

2017-01-01

Tissue repair is an essential process that reestablishes tissue integrity and regular function. Nevertheless, different therapeutic factors and clinical conditions may interfere in this process of periapical healing. This review aims to discuss the important therapeutic factors associated with the clinical protocol used during root canal treatment and to highlight the systemic conditions associated with the periapical healing process of endodontically treated teeth. The antibacterial strategies indicated in the conventional treatment of an inflamed and infected pulp and the modulation of the host's immune response may assist in tissue repair, if wound healing has been hindered by infection. Systemic conditions, such as diabetes mellitus and hypertension, can also inhibit wound healing. The success of root canal treatment is affected by the correct choice of clinical protocol. These factors are dependent on the sanitization process (instrumentation, irrigant solution, irrigating strategies, and intracanal dressing), the apical limit of the root canal preparation and obturation, and the quality of the sealer. The challenges affecting the healing process of endodontically treated teeth include control of the inflammation of pulp or infectious processes and simultaneous neutralization of unpredictable provocations to the periapical tissue. Along with these factors, one must understand the local and general clinical conditions (systemic health of the patient) that affect the outcome of root canal treatment prediction.

Factors affecting the periapical healing process of endodontically treated teeth

PubMed Central

Holland, Roberto; Gomes, João Eduardo; Cintra, Luciano Tavares Angelo; Queiroz, Índia Olinta de Azevedo; Estrela, Carlos

2017-01-01

Abstract Tissue repair is an essential process that reestablishes tissue integrity and regular function. Nevertheless, different therapeutic factors and clinical conditions may interfere in this process of periapical healing. This review aims to discuss the important therapeutic factors associated with the clinical protocol used during root canal treatment and to highlight the systemic conditions associated with the periapical healing process of endodontically treated teeth. The antibacterial strategies indicated in the conventional treatment of an inflamed and infected pulp and the modulation of the host's immune response may assist in tissue repair, if wound healing has been hindered by infection. Systemic conditions, such as diabetes mellitus and hypertension, can also inhibit wound healing. The success of root canal treatment is affected by the correct choice of clinical protocol. These factors are dependent on the sanitization process (instrumentation, irrigant solution, irrigating strategies, and intracanal dressing), the apical limit of the root canal preparation and obturation, and the quality of the sealer. The challenges affecting the healing process of endodontically treated teeth include control of the inflammation of pulp or infectious processes and simultaneous neutralization of unpredictable provocations to the periapical tissue. Along with these factors, one must understand the local and general clinical conditions (systemic health of the patient) that affect the outcome of root canal treatment prediction. PMID:29069143

Impacts of irrigation on groundwater depletion in the North China Plain

NASA Astrophysics Data System (ADS)

Ge, Yuqi; Lei, Huimin

2017-04-01

Groundwater resources is an essential water supply for agriculture in the North China Plain (NCP) which is one of the most important food production areas in China. In the past decades, excessive groundwater-fed irrigation in this area has caused sharp decline in groundwater table. However, accurate monitoring on the net groundwater exploitation is still difficult, mainly due to a lack of complete groundwater exploitation monitoring network. This hinders an accurate evaluation of the effects of agricultural managements on shallow groundwater table. In this study, we use an existing method to estimate the net irrigation amount at the county level, and evaluate the effects of current agricultural management on groundwater depletion. We apply this method in five typical counties in the NCP to estimate annual net irrigation amount from 2002 to 2015, based on meteorological data (2002-2015) and remote sensing ET data (2002-2015) . First, an agro-hydrological model (Soil-Water-Atmosphere-Plant, SWAP) is calibrated and validated at field scale based on the measured data from flux towers. Second, the model is established at reginal scale by spatial discretization. Third, we use an optimization tool (Parameter ESTimation, PEST) to optimize the irrigation parameter in SWAP so as the simulated evapotranspiration (ET) by SWAP is closest to the remote sensing ET. We expect that the simulated irrigation amount from the optimized parameter is the estimated net irrigation amount. Finally, the contribution of agricultural management to the observed groundwater depletion is assessed by calculating the groundwater balance which considers the estimated net irrigation amount, observed lateral groundwater, rainfall recharge, deep seepage, evaporation from phreatic water and domestic water use. The study is expected to give a scientific basis for alleviating the over-exploitation of groundwater resources in the area.

Bladder irrigation and urothelium disruption: a reminder apropos of a case of fatal fluid absorption.

PubMed

Di Paolo, Marco; Bugelli, Valentina; Di Luca, Alessandro; Turillazzi, Emanuela

2014-11-20

Irrigation or washouts of the bladder are usually performed in various clinical settings. In the 1980s Elliot and colleagues argued that urothelial damage could occur after washouts and irrigations of the bladder. The exact mechanism underlying urothelial damage has not yet been discovered. To our knowledge, this is the first report of fatal fluid overload and pulmonary edema, due to urothelium disruption occurring during bladder irrigation, approached performing complete histological and immunohistochemical investigation on bladder specimens. The exposed case deserves attention since it demonstrates that, although very rarely, irrigation or washouts of the bladder may have unexpected serious clinical consequences. An 85 year-old Caucasian man, unable to eat independently and whose fluid intake was controlled, underwent continuous bladder irrigation with a 3-way catheter due to a severe episode of macrohematuria. During the third day of hospitalization, while still undergoing bladder irrigation, he suddenly experienced extreme shortness of breath, breathing difficulties, and cough with frothy sputum. His attending nurse immediately noted that there was no return of the fluid (5 liters) introduced through bladder irrigation. He was treated urgently with hemodialysis. At the beginning of the dialysis treatment, the patient had gained 7.4 kg since the previous measurement (24 hours prior) without any clear explanation. Although a significant weight loss (from 81 to 76 kg) due to the dialysis procedure, the patient died shortly after the final treatment. The autopsy revealed that the brain and the lungs were heavily edematous. Microscopic examination of bladder specimens revealed interstitial and mucosal swelling, and loss of the superficial cell layer. Intermediate and basal urothelial cells were preserved. Altogether the above mentioned findings were suggestive of a diffuse disruption of the urothelium. In conclusion the death of the man was attributed to an acute severe pulmonary edema due to massive fluid absorption. Our case demonstrates that urothelium disruption may occur during irrigation and washouts of the bladder, also in the absence of other well-known predisposing conditions. Inappropriate use of bladder irrigation should be avoided and a close attention is required of the fluid balance is mandatory when irrigating the bladder.

Investigations into in situ Enterococcus faecalis biofilm removal by passive and active sodium hypochlorite irrigation delivered into the lateral canal of a simulated root canal model.

PubMed

Mohmmed, S A; Vianna, M E; Penny, M R; Hilton, S T; Mordan, N J; Knowles, J C

2018-06-01

To investigate in situ Enterococcus faecalis biofilm removal from the lateral canal of a simulated root canal system using passive or active irrigation protocols. Root canal models (n = 43) were manufactured from transparent resin materials using 3D printing. Each canal was created with an 18 mm length, apical size 30, a .06 taper and a lateral canal of 3 mm length, with 0.3 mm diameter. Biofilms were grown in the lateral canal and apical 3 mm of the main canal for 10 days. Three models from each group were examined for residual biofilm using SEM. The other forty models were divided into four groups (n = 10). The models were observed under a fluorescence microscope. Following 60 s of 9 mL of 2.5% NaOCl irrigation using syringe and needle, the irrigant was either left stagnant in the canal or activated using gutta-percha, sonic or ultrasonic methods for 30 s. Images were then captured every second using an external camera. The residual biofilm percentages were measured using image analysis software. The data were analysed using generalized linear mixed models. A significance level of 0.05 was used throughout. The greatest level of biofilm removal was obtained with ultrasonic agitation (66.76%) followed by sonic (45.49%), manual agitation (43.97%) and passive irrigation groups (38.67%), respectively. The differences were significant between the residual biofilm in the passive irrigation and both sonic and ultrasonic groups (P = 0.001). Agitation resulted in better penetration of 2.5% NaOCl into the lateral canal of an artificial root canal model. Ultrasonic agitation of NaOCl improved the removal of biofilm. © 2017 International Endodontic Journal. Published by John Wiley & Sons Ltd.

Field Evidence Supporting Conventional Onion Curing Practices as a Strategy To Mitigate Escherichia coli Contamination from Irrigation Water.

PubMed

Wright, Daniel; Feibert, Erik; Reitz, Stuart; Shock, Clint; Waite-Cusic, Joy

2018-03-01

The Produce Safety Rule of the U.S. Food Safety Modernization Act includes restrictions on the use of agricultural water of poor microbiological quality. Mitigation options for poor water quality include the application of an irrigation-to-harvest interval of <4 days; however, dry bulb onion production includes an extended irrigation-to-harvest interval (<30 days). This study evaluated conventional curing practices for mitigating Escherichia coli contamination in a field setting. Well water inoculated with rifampin-resistant E. coli (1, 2, or 3 log CFU/mL) was applied to onion fields (randomized block design; n = 5) via drip tape on the final day of irrigation. Onions remained undisturbed for 7 days and were then lifted to the surface to cure for an additional 21 days before harvest. Water, onions, and soil were tested for presence of rifampin-resistant E. coli. One day after irrigation, 13.3% of onions (20 of 150) receiving the poorest quality water (3 log CFU/mL) tested positive for E. coli; this prevalence was reduced to 4% (6 of 150 onions) after 7 days. Regardless of inoculum level, E. coli was not detected on any onions beyond 15 days postirrigation. These results support conventional dry bulb onion curing practices as an effective strategy to mitigate microbiological concerns associated with poor quality irrigation water.

Salinity control in a clay soil beneath an orchard irrigated with treated waste water in the presence of a high water table: A numerical study

NASA Astrophysics Data System (ADS)

Russo, David; Laufer, Asher; Bardhan, Gopali; Levy, Guy J.

2015-12-01

A citrus orchard planted on a structured, clay soil associated with a high water table, irrigated by drip irrigation system using treated waste water (TWW) and local well water (LWW) was considered here. The scope of the present study was to analyze transport of mixed-ion, interacting salts in a combined vadose zone-groundwater flow system focusing on the following issues: (i) long-term effects of irrigation with TWW on the response of the flow system, identifying the main factors (e.g., soil salinity, soil sodicity) that control these effects, and (ii) salinity control aiming at improving both crop productivity and groundwater quality. To pursue this two-fold goal, 3-D numerical simulations of field-scale flow and transport were performed for an extended period of time, considering realistic features of the soil, water table, crop, weather and irrigation, and the coupling between the flow and the transport through the dependence of the soil hydraulic functions, K(ψ) and θ(ψ), on soil solution concentration C, and sodium adsorption ratio, SAR. Results of the analyses suggest that in the case studied, the long-term effect of irrigation with TWW on the response of the flow system is attributed to the enhanced salinity of the TWW, and not to the increase in soil sodicity. The latter findings are attributed to: (i) the negative effect of soil salinity on water uptake, and the tradeoff between water uptake and drainage flux, and, concurrently, solute discharge below the root zone; and, (ii) the tradeoff between the effects of C and SAR on K(ψ) and θ(ψ). Furthermore, it was demonstrated that a data-driven protocol for soil salinity control, based on alternating irrigation water quality between TWW and desalinized water, guided by the soil solution salinity at the centroid of the soil volume active in water uptake, may lead to a substantial increase in crop yield, and to a substantial decrease in the salinity load in the groundwater.

Incidence of silent cerebral thromboembolic lesions after atrial fibrillation ablation may change according to technology used: comparison of irrigated radiofrequency, multipolar nonirrigated catheter and cryoballoon.

PubMed

Gaita, Fiorenzo; Leclercq, Jean François; Schumacher, Burghard; Scaglione, Marco; Toso, Elisabetta; Halimi, Franck; Schade, Anja; Froehner, Steffen; Ziegler, Volker; Sergi, Domenico; Cesarani, Federico; Blandino, Alessandro

2011-09-01

Silent cerebral ischemic lesions have recently emerged as the most frequent complications after pulmonary vein isolation (PVI). To reduce thromboembolic complications, new types of catheters and energy source have been introduced in clinical practice. The study purpose is to compare the incidence of new silent cerebral ischemic events in patients with paroxysmal atrial fibrillation (PAF) undergoing PVI with different ablation technologies. One hundred and eight patients (67% men; age 56 ± 9 years) with PAF were enrolled in a consecutive manner to undergo PVI performed with irrigated radiofrequency (RF) catheter (Group 1, 36 patients), multielectrode catheter (PVAC) associated with duty-cycled RF generator (Group 2, 36 patients) and cryoballoon (Group 3, 36 patients). The protocol included a cerebral magnetic resonance imaging before and after the procedure. After PVI, the following patients showed new silent cerebral ischemic lesions at postprocedural cerebral MRI: 3 patients in Group 1 (8.3%), 14 patients in Group 2 (38.9%), 2 patients in Group 3 (5.6%). PVAC related to higher incidence of silent cerebral ischemic events compared to irrigated RF (P = 0.002) and cryoballoon (P = 0.001), whereas no statistical differences were found between irrigated RF catheter and cryoballoon groups (8.3% vs 5.6%, P = 0.5). At the multivariate analysis, the only independent predictor of new ischemic asymptomatic cerebral lesions after PVI was ablation performed with PVAC (OR 1.48 95% CI 1.19-1.62, P < 0.001). The incidence of silent cerebral lesions after PVI is different depending on technologies used: PVAC increases the risk of 1.48 times compared to irrigated RF and cryoballoon ablation.  © 2011 Wiley Periodicals, Inc.

Modeling the interannual variability of microbial quality metrics of irrigation water in a Pennsylvania stream.

PubMed

Hong, Eun-Mi; Shelton, Daniel; Pachepsky, Yakov A; Nam, Won-Ho; Coppock, Cary; Muirhead, Richard

2017-02-01

Knowledge of the microbial quality of irrigation waters is extremely limited. For this reason, the US FDA has promulgated the Produce Rule, mandating the testing of irrigation water sources for many farms. The rule requires the collection and analysis of at least 20 water samples over two to four years to adequately evaluate the quality of water intended for produce irrigation. The objective of this work was to evaluate the effect of interannual weather variability on surface water microbial quality. We used the Soil and Water Assessment Tool model to simulate E. coli concentrations in the Little Cove Creek; this is a perennial creek located in an agricultural watershed in south-eastern Pennsylvania. The model performance was evaluated using the US FDA regulatory microbial water quality metrics of geometric mean (GM) and the statistical threshold value (STV). Using the 90-year time series of weather observations, we simulated and randomly sampled the time series of E. coli concentrations. We found that weather conditions of a specific year may strongly affect the evaluation of microbial quality and that the long-term assessment of microbial water quality may be quite different from the evaluation based on short-term observations. The variations in microbial concentrations and water quality metrics were affected by location, wetness of the hydrological years, and seasonality, with 15.7-70.1% of samples exceeding the regulatory threshold. The results of this work demonstrate the value of using modeling to design and evaluate monitoring protocols to assess the microbial quality of water used for produce irrigation. Copyright © 2016 Elsevier Ltd. All rights reserved.

Simulated Impacts of Climate Change on Water Use and Yield of Irrigated Sugarcane in South Africa

NASA Technical Reports Server (NTRS)

Jones, M.R; Singels, A.; Ruane, A. C.

2015-01-01

Reliable predictions of climate change impacts on water use, irrigation requirements and yields of irrigated sugarcane in South Africa (a water-scarce country) are necessary to plan adaptation strategies. Although previous work has been done in this regard, methodologies and results vary considerably. The objectives were (1) to estimate likely impacts of climate change on sugarcane yields, water use and irrigation demand at three irrigated sugarcane production sites in South Africa (Malelane, Pongola and La Mercy) for current (1980-2010) and future (2070-2100) climate scenarios, using an approach based on the Agricultural Model Inter-comparison and Improvement Project (AgMIP) protocols; and (2) to assess the suitability of this methodology for investigating climate change impacts on sugarcane production. Future climate datasets were generated using the Delta downscaling method and three Global Circulation Models (GCMs) assuming atmospheric CO2 concentration [CO2] of 734 ppm(A2 emissions scenario). Yield and water use were simulated using the DSSAT-Canegro v4.5 model. Irrigated cane yields are expected to increase at all three sites (between 11 and 14%), primarily due to increased interception of radiation as a result of accelerated canopy development. Evapotranspiration and irrigation requirements increased by 11% due to increased canopy cover and evaporative demand. Sucrose yields are expected to decline because of increased consumption of photo-assimilate for structural growth and maintenance respiration. Crop responses in canopy development and yield formation differed markedly between the crop cycles investigated. Possible agronomic implications of these results include reduced weed control costs due to shortened periods of partial canopy, a need for improved efficiency of irrigation to counter increased demands, and adjustments to ripening and harvest practices to counter decreased cane quality and optimize productivity. Although the Delta climate data downscaling method is considered robust, accurate and easily-understood, it does not change the future number of rain-days per month. The impacts of this and other climate data simplifications ought to be explored in future work. Shortcomings of the DSSAT-Canegro model include the simulated responses of phenological development, photosynthesis and respiration processes to high temperatures, and the disconnect between simulated biomass accumulation and expansive growth. Proposed methodology refinements should improve the reliability of predicted climate change impacts on sugarcane yield.

Antibacterial properties of silver nanoparticles as a root canal irrigant against Enterococcus faecalis biofilm and infected dentinal tubules.

PubMed

Rodrigues, C T; de Andrade, F B; de Vasconcelos, L R S M; Midena, R Z; Pereira, T C; Kuga, M C; Duarte, M A H; Bernardineli, N

2018-02-03

To evaluate the antimicrobial action of an irrigant containing silver nanoparticles in an aqueous vehicle (AgNp), sodium hypochlorite and chlorhexidine against Enterococcus faecalis biofilm and infected dentinal tubules. Bovine dentine blocks were used for E. faecalis biofilm development for 21 days and irrigated with 94 ppm AgNp solution, 2.5% NaOCl and 2% chlorhexidine for 5, 15 and 30 min. For infection of dentinal tubules with E. faecalis, dentine specimens from bovine incisors were submitted to a contamination protocol over 5 days, with eight centrifugation cycles on every alternate day, and irrigated with the same solutions and time intervals used for the biofilm. The specimens were stained with the Live/Dead technique and evaluated using a confocal laser scanning microscope (CLSM). The bioImage_L software was used for measurement of the total biovolume of biofilm in μm 3 and percentage of viable bacteria (green cells) in biofilm and in dentinal tubules found after the irrigation. Statistical analyses were performed using Kruskal-Wallis and Dunn's tests for quantification of viable cells in biofilm, the Friedman test for comparisons of viable bacteria in dentinal tubules in different areas of the root canal and the Mann-Whitney U-test to compare the action of the irrigants between the two methods (P < 0.05). The AgNp solution eliminated fewer bacteria, but was able to dissolve more biofilm compared with chlorhexidine (P < 0.05). NaOCl had the greatest antimicrobial activity and biofilm dissolution capacity. AgNp solution had less antimicrobial action in infected dentinal tubules compared with NaOCl (P < 0.05). The AgNp solution after 5 min was more effective in eliminating planktonic bacteria in dentinal tubules than in biofilm, but at 30 min fewer viable bacteria were observed in the biofilm compared with intratubular dentine (P < 0.05). AgNp irrigant was not as effective against E. faecalis compared to solutions commonly used in root canal treatment. NaOCl is appropriate as an irrigant because it was effective in disrupting biofilm and in eliminating bacteria in biofilms and in dentinal tubules. © 2018 International Endodontic Journal. Published by John Wiley & Sons Ltd.

Intermediate treatments

Treesearch

John R. Jones; Wayne D. Shepperd

1985-01-01

Intermediate treatments are those applied after a new stand is successfully established and before the final harvest. These include not only intermediate cuttings - primarily thinning - but also fertilization, irrigation, and protection of the stand from damaging agents.

Prophylaxis of surgical site infection in adult spine surgery: A systematic review.

PubMed

Yao, Reina; Tan, Terence; Tee, Jin Wee; Street, John

2018-06-01

Surgical site infection (SSI) remains a significant source of morbidity in spine surgery, with reported rates varying from 0.7 to 16%. To systematically review and evaluate the evidence for strategies for prophylaxis of SSI in adult spine surgery in the last twenty years. Two independent systematic searches were conducted, at two international spine centers, encompassing PubMed, ClinicalTrials.gov, Cochrane Database, EBSCO Medline, ScienceDirect, Ovid Medline, EMBASE (Ovid), and MEDLINE. References were combined and screened, then distilled to 69 independent studies for final review. 11 randomized controlled trials (RCTs), 51 case-controlled studies (CCS), and 7 case series were identified. Wide variation exists in surgical indications, approaches, procedures, and even definitions of SSI. Intra-wound vancomycin powder was the most widely studied intervention (19 studies, 1 RCT). Multiple studies examined perioperative antibiotic protocols, closed-suction drainage, povidone-iodine solution irrigation, and 2-octyl-cyanoacrylate skin closure. 18 interventions were examined by a single study only. There is limited evidence for the efficacy of intra-wound vancomycin. There is strong evidence that closed-suction drainage does not affect SSI rates, while there is moderate evidence for the efficacy of povidone-iodine irrigation and that single-dose preoperative antibiotics is as effective as multiple doses. Few conclusions can be drawn about other interventions given the paucity and poor quality of studies. While a small body of evidence underscores a select few interventions for SSI prophylaxis in adult spine surgery, most proposed measures have not been investigated beyond a single study. Further high level evidence is required to justify SSI preventative treatments. Copyright © 2018 Elsevier Ltd. All rights reserved.

The antimicrobial effectiveness of photodynamic therapy used as an addition to the conventional endodontic re-treatment: a clinical study.

PubMed

Jurič, Ivona Bago; Plečko, Vanda; Pandurić, Dragana Gabrić; Anić, Ivica

2014-12-01

The purpose of the study was to evaluate the efficacy of antimicrobial photodynamic therapy (aPDT) used as an adjunct to the endodontic re-treatment in the eradication of microorganisms from previously filled root canals. The study sample consisted of 21 randomly selected patients with root filled and infected root canal system with chronic apical periodontitis on incisors or canines, who have had previously endodontic treatment. Microbiological samples from the root canals were collected after accessing the canal, following the endodontic re-treatment and after the aPDT procedure. During instrumentation, the root canals were irrigated with 2.5% sodium hypochlorite (NaOCl), and the final irrigation protocol included 17% ethylenediaminetetraacetic acid followed by NaOCl. Root canals were filled with a phenothiazinium chloride and irradiated with a diode laser (λ=660 nm, 100 mW) for 1 min. Microbiological samples from the root canals were cultivated on selective plates, and the identification was done by micromorphology, macromorphology and different API strips as well as bacterial counts (colony forming units). Fourteen bacteria species were isolated from the root canals initially, with a mean value of 4.57 species per canal. Although endodontic re-treatment alone produced a significant reduction in the number of bacteria species (p<0.001), the combination of endodontic treatment and aPDT was statistically more effective (p<0.001). No bacteria were cultivated from the main root canals of 11 teeth. The results indicated that the aPDT used as an adjunct to the conventional endodontic therapy achieved a significant further reduction of intracanal microbial load. Copyright © 2014 Elsevier B.V. All rights reserved.

1064-nm Nd:YAG and 980-nm Diode Laser EDTA Agitation on the Retention of an Epoxy-Based Sealer to Root Dentin.

PubMed

Macedo, Helena Suleiman de; Messias, Danielle Cristine Furtado; Rached-Júnior, Fuad Jacob; Oliveira, Ligia Teixeira de; Silva-Sousa, Yara Teresinha Correa; Raucci-Neto, Walter

2016-01-01

Root canal irrigants are used to minimize the negative effects of smear layer on endodontic sealer retention. The aim of this study was to evaluate the efficacy of agitation of 17% ethylenediaminetetraacetic acid (EDTA) with ultrasonic, 1064-nm Nd:YAG and 980-nm diode laser on the retention of an epoxy-based sealer to the root canal walls. Forty single-rooted bovine teeth were instrumented with ProTaper rotary system and divided into four groups according to the final irrigation protocol (n = 10): (1) 17% EDTA (control); (2) 17% EDTA with 50-s ultrasonic agitation; (3) 17% EDTA with 50-s diode laser (2-W) agitation; and (4) 17% EDTA with 50-s Nd:YAG (1.5-W) laser agitation. After endodontic filling with gutta-percha F5 master cone and Sealer 26, the roots were sectioned at the cervical, middle, and apical root thirds to obtain 1.5-mm slices. Push-out tests were performed using a universal testing machine at a 1 mm/min crosshead speed. Data were analyzed using two-way ANOVA and Tukey's tests (α=0.05). Apical root thirds had significant higher retention values than cervical and middle thirds (p < 0.05). EDTA with 1064-nm Nd:YAG or 980-nm diode laser presented the highest retention values and was significantly different from EDTA with ultrasonic agitation and EDTA only (p < 0.05). Adhesive failures were predominant to EDTA only group. Mixed failures were predominant to all agitation groups. 1064-nm Nd:YAG and 980-nm diode laser EDTA agitation enhanced the retention of the epoxy-based sealer to the root canal walls compared with that due to EDTA only or EDTA with ultrasonic agitation.

Earlier nesting by generalist predatory bird is associated with human responses to climate change.

PubMed

Smith, Shawn H; Steenhof, Karen; McClure, Christopher J W; Heath, Julie A

2017-01-01

Warming temperatures cause temporal changes in growing seasons and prey abundance that drive earlier breeding by birds, especially dietary specialists within homogeneous habitat. Less is known about how generalists respond to climate-associated shifts in growing seasons or prey phenology, which may occur at different rates across land cover types. We studied whether breeding phenology of a generalist predator, the American kestrel (Falco sparverius), was associated with shifts in growing seasons and, presumably, prey abundance, in a mosaic of non-irrigated shrub/grasslands and irrigated crops/pastures. We examined the relationship between remotely-sensed normalized difference vegetation index (NDVI) and abundance of small mammals that, with insects, constitute approximately 93% of kestrel diet biomass. We used NDVI to estimate the start of the growing season (SoGS) in irrigated and non-irrigated lands from 1992 to 2015 and tested whether either estimate of annual SoGS predicted the timing of kestrel nesting. Finally, we examined relationships among irrigated SoGS, weather and crop planting. NDVI was a useful proxy for kestrel prey because it predicted small mammal abundance and past studies showed that NDVI predicts insect abundance. NDVI-estimated SoGS advanced significantly in irrigated lands (β = -1·09 ± 0·30 SE) but not in non-irrigated lands (β = -0·57 ± 0·53). Average date of kestrel nesting advanced 15 days in the past 24 years and was positively associated with the SoGS in irrigated lands, but not the SoGS in non-irrigated lands. Advanced SoGS in irrigated lands was related to earlier planting of crops after relatively warm winters, which were more common in recent years. Despite different patterns of SoGS change between land cover types, kestrel nesting phenology shifted with earlier prey availability in irrigated lands. Kestrels may preferentially track prey in irrigated lands over non-irrigated lands because of higher quality prey on irrigated lands, or earlier prey abundance may release former constraints on other selective pressures to breed early, such as seasonal declines in fecundity or competition for high-quality mates. This is one of the first examples of an association between human adaptation to climate change and shifts in breeding phenology of wildlife. © 2016 The Authors. Journal of Animal Ecology published by John Wiley & Sons Ltd on behalf of British Ecological Society.

Total selenium in irrigation drain inflows to the Salton Sea, California, April 2009

USGS Publications Warehouse

May, Thomas W.; Walther, Michael J.; Saiki, Michael K.; Brumbaugh, William G.

2009-01-01

This report presents the results for the final sampling period (April 2009) of a 4-year monitoring program to characterize selenium concentrations in selected irrigation drains flowing into the Salton Sea, California. Total selenium and total suspended solids were determined in water samples. Total selenium, percent total organic carbon, and particle size were determined in sediments. Mean total selenium concentrations in water ranged from 0.98 to 22.9 micrograms per liter. Total selenium concentrations in sediment ranged from 0.078 to 5.0 micrograms per gram dry weight.

River eutrophication: irrigated vs. non-irrigated agriculture through different spatial scales.

PubMed

Monteagudo, Laura; Moreno, José Luis; Picazo, Félix

2012-05-15

The main objective of this study was to determine how spatial scale may affect the results when relating land use to nutrient enrichment of rivers and, secondly, to investigate which agricultural practices are more responsible for river eutrophication in the study area. Agriculture was split into three subclasses (irrigated, non-irrigated and low-impact agriculture) which were correlated to stream nutrient concentration on four spatial scales: large scale (drainage area of total subcatchment and 100 m wide subcatchment corridors) and local scale (5 and 1 km radius buffers). Nitrate, ammonium and orthophosphate concentrations and land use composition (agriculture, urban and forest) were measured at 130 river reaches in south-central Spain during the 2001-2009 period. Results suggested that different spatial scales may lead to different conclusions. Spatial autocorrelation and the inadequate representation of some land uses produced unreal results on large scales. Conversely, local scales did not show data autocorrelation and agriculture subclasses were well represented. The local scale of 1 km buffer was the most appropriate to detect river eutrophication in central Spanish rivers, with irrigated cropland as the main cause of river pollution by nitrate. As regards river management, a threshold of 50% irrigated cropland within a 1 km radius buffer has been obtained using breakpoint regression analysis. This means that no more than 50% of irrigation croplands should be allowed near river banks in order to avoid river eutrophication. Finally, a methodological approach is proposed to choose the appropriate spatial scale when studying river eutrophication caused by diffuse pollution like agriculture. Copyright © 2012 Elsevier Ltd. All rights reserved.

Intra-Operative Surgical Irrigation of the Surgical Incision: What Does the Future Hold-Saline, Antibiotic Agents, or Antiseptic Agents?

PubMed

Edmiston, Charles E; Leaper, David J

2016-12-01

Intra-operative surgical site irrigation (lavage) is common practice in surgical procedures in general, with all disciplines advocating some form of irrigation before incision closure. This practice, however, has been neither standardized nor is there compelling evidence that it effectively reduces the risk of surgical site infection (SSI). This narrative review addresses the laboratory and clinical evidence that is available to support the practice of irrigation of the abdominal cavity and superficial/deep incisional tissues, using specific irrigation solutions at the end of an operative procedure to reduce the microbial burden at wound closure. Review of PubMed and OVID for pertinent, scientific, and clinical publications in the English language was performed. Incision irrigation was found to afford a three-fold benefit: First, to hydrate the bed; second, to assist in allowing better examination of the area immediately before closure; and finally, by removing superficial and deep incisional contamination and lowering the bioburden, expedite the healing process. The clinical practice of intra-operative peritoneal lavage is highly variable and is dependent solely on surgeon preference. By contrast, intra-operative irrigation after device-related procedures has become a standard of care for the prophylaxis of acute peri-prosthetic infection. The clinical evidence that supports the use of antibiotic irrigation is limited and based on retrospective analysis and few acceptable randomized controlled trials. The results of laboratory and animal studies using aqueous 0.05% chlorhexidine gluconate are favorable, suggesting that further studies are justified to determine its clinical efficacy. The adoption of appropriate and standardized intra-operative irrigation practices into peri-operative care bundles, which include other evidence-based strategies (weight-based antimicrobial prophylaxis, antimicrobial sutures, maintenance of normothermia, and glycemic control), offers an inexpensive and effective method to reduce the risk of post-operative SSI and deserves further evaluation.

Comparison of apical extrusion of sodium hypochlorite using 4 different root canal irrigation techniques.

PubMed

İriboz, Emre; Bayraktar, Koral; Türkaydın, Dilek; Tarçın, Bilge

2015-03-01

We compared the apical extrusion of sodium hypochlorite delivered with a 27-G needle, self-adjusting file (SAF), passive ultrasonic irrigation, or the EndoVac system (SybronEndo, Orange, CA) during the instrumentation and final irrigation of root canals. Matched paired single-canal teeth were divided into 8 groups. The experimental groups were needle irrigation size #30 (NI30) and #50 (NI50), SAF size #30 (SAF30) and #50 (SAF50), passive ultrasonic irrigation size #30 (PUI30) and #50 (PUI50), and EndoVac size #30 (EV30) and #50 (EV50). Teeth were embedded in 0.2% agarose gel (pH = 7.4) containing 1 mL 0.1% m-Cresol purple (Sigma-Aldrich, St Louis, MO), which changes color at a pH level of 9.0. Root canals were irrigated with sodium hypochlorite and EDTA using 4 different techniques, and the amount of irrigant was controlled. Standardized digital photographs were taken 20 minutes after the first irrigant was used and were analyzed to determine the amount of extrusion (expressed as a percentage of total pixels). The amounts of apical extrusion obtained in the NI30, NI50, SAF30, SAF50, PUI30, PUI50, EV30, and EV50 groups were 30% (3/10), 50% (5/10), 20% (2/10), 70% (7/10), 40% (4/10), 40% (4/10), 10% (1/10), and 10% (1/10), respectively. The overall extrusion frequency, regardless of the apical preparation size, was 40% (8/20) for needle, 45% (9/20) for SAF, 40% (8/20) for ultrasonic irrigation, and 10% (2/20) for EndoVac. Although the SAF group showed more extrusion, the percentage of pixels was significantly higher in the needle irrigation group (P < .01). The EndoVac group showed significantly lower extrusion values than the other techniques in terms of the number of teeth and pixels (P < .05 and P < .01, respectively). The risk of apical extrusion is significantly lower with the EndoVac in comparison with the 3 other techniques. Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

A Trial of Wound Irrigation in the Initial Management of Open Fracture Wounds.

PubMed

Bhandari, Mohit; Jeray, Kyle J; Petrisor, Brad A; Devereaux, P J; Heels-Ansdell, Diane; Schemitsch, Emil H; Anglen, Jeff; Della Rocca, Gregory J; Jones, Clifford; Kreder, Hans; Liew, Susan; McKay, Paula; Papp, Steven; Sancheti, Parag; Sprague, Sheila; Stone, Trevor B; Sun, Xin; Tanner, Stephanie L; Tornetta, Paul; Tufescu, Ted; Walter, Stephen; Guyatt, Gordon H

2015-12-31

The management of open fractures requires wound irrigation and débridement to remove contaminants, but the effectiveness of various pressures and solutions for irrigation remains controversial. We investigated the effects of castile soap versus normal saline irrigation delivered by means of high, low, or very low irrigation pressure. In this study with a 2-by-3 factorial design, conducted at 41 clinical centers, we randomly assigned patients who had an open fracture of an extremity to undergo irrigation with one of three irrigation pressures (high pressure [>20 psi], low pressure [5 to 10 psi], or very low pressure [1 to 2 psi]) and one of two irrigation solutions (castile soap or normal saline). The primary end point was reoperation within 12 months after the index surgery for promotion of wound or bone healing or treatment of a wound infection. A total of 2551 patients underwent randomization, of whom 2447 were deemed eligible and included in the final analyses. Reoperation occurred in 109 of 826 patients (13.2%) in the high-pressure group, 103 of 809 (12.7%) in the low-pressure group, and 111 of 812 (13.7%) in the very-low-pressure group. Hazard ratios for the three pairwise comparisons were as follows: for low versus high pressure, 0.92 (95% confidence interval [CI], 0.70 to 1.20; P=0.53), for high versus very low pressure, 1.02 (95% CI, 0.78 to 1.33; P=0.89), and for low versus very low pressure, 0.93 (95% CI, 0.71 to 1.23; P=0.62). Reoperation occurred in 182 of 1229 patients (14.8%) in the soap group and in 141 of 1218 (11.6%) in the saline group (hazard ratio, 1.32, 95% CI, 1.06 to 1.66; P=0.01). The rates of reoperation were similar regardless of irrigation pressure, a finding that indicates that very low pressure is an acceptable, low-cost alternative for the irrigation of open fractures. The reoperation rate was higher in the soap group than in the saline group. (Funded by the Canadian Institutes of Health Research and others; FLOW ClinicalTrials.gov number, NCT00788398.).

Groundwater recharge in irrigated semi-arid areas: quantitative hydrological modelling and sensitivity analysis

NASA Astrophysics Data System (ADS)

Jiménez-Martínez, Joaquín; Candela, Lucila; Molinero, Jorge; Tamoh, Karim

2010-12-01

For semi-arid regions, methods of assessing aquifer recharge usually consider the potential evapotranspiration. Actual evapotranspiration rates can be below potential rates for long periods of time, even in irrigated systems. Accurate estimations of aquifer recharge in semi-arid areas under irrigated agriculture are essential for sustainable water-resources management. A method to estimate aquifer recharge from irrigated farmland has been tested. The water-balance-modelling approach was based on VisualBALAN v. 2.0, a computer code that simulates water balance in the soil, vadose zone and aquifer. The study was carried out in the Campo de Cartagena (SE Spain) in the period 1999-2008 for three different groups of crops: annual row crops (lettuce and melon), perennial vegetables (artichoke) and fruit trees (citrus). Computed mean-annual-recharge values (from irrigation+precipitation) during the study period were 397 mm for annual row crops, 201 mm for perennial vegetables and 194 mm for fruit trees: 31.4, 20.7 and 20.5% of the total applied water, respectively. The effects of rainfall events on the final recharge were clearly observed, due to the continuously high water content in soil which facilitated the infiltration process. A sensitivity analysis to assess the reliability and uncertainty of recharge estimations was carried out.

Effective analysis of the use of peracetic acid after instrumentation of root canals contaminated with Enterococcus faecalis.

PubMed

Cord, Caroline Berwanger; Velasco, Rafael Vidal Cortez; Ribeiro Melo Lima, Laíla Fernanda; Rocha, Daniel Guimarães Pedro; da Silveira Bueno, Carlos Eduardo; Pinheiro, Sérgio Luiz

2014-08-01

The aim of this study was to evaluate the effectiveness of peracetic acid (PAA) in cleaning root canals contaminated with Enterococcus faecalis. Sixty first and second mandibular molars were used. Their mesiobuccal canals were prepared with the Reciproc System (VDW, Munich, Germany). The canals were irrigated with 10 mL saline during instrumentation. The teeth were randomly divided into 3 groups (n = 20), according to the irrigation solution to be used after instrumentation: group PAA (5 mL 1% PAA), group EDTA/sodium hypochlorite (NaOCl) (5 mL 17% EDTA followed by 5 mL 2.5% sodium hypochlorite), and group S (5 mL saline). Microbiological samples were collected before instrumentation and after final irrigation. Bacterial quantification was performed by counting the number of colony-forming units (CFUs/mL). The results were analyzed by the nonparametric Wilcoxon and Kruskal-Wallis tests. The 3 groups showed a significant reduction (P < .05) in CFUs/mL after final irrigation. PAA and NaOCl associated with EDTA produced a significantly higher reduction in CFUs/mL (P < .05) compared with saline. There was no statistically significant difference between PAA and EDTA + 2.5% NaOCl (P > .05). According to the results of the present study, the effectiveness of 1% PAA was similar to that of 17% EDTA + 2.5% NaOCl in cleaning curved root canals contaminated with E. faecalis. Copyright © 2014 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Safe and High Quality Food Production using Low Quality Waters and Improved Irrigation Systems and Management (SAFIR)

NASA Astrophysics Data System (ADS)

Cary, L.; Kloppmann, W.; Battilani, A.; Bertaki, M.; Blagojevic, S.; Chartzoulakis, K.; Dalsgaard, A.; Forslund, A.; Jovanovic, Z.; Kasapakis, I.

2009-04-01

The safe use of treated domestic wastewater for irrigation needs to address the risks for humans (workers, exposed via contact with irrigation water, soil, crops and food, consumers, exposed via ingestion of fresh and processed food), for animals (via ingestion of crops an soil), for the crops and agricultural productivity (via salinity and trace element uptake), for soil (via accumulation or release of pollutants) as well as for surface, groundwaters and the associated ecosystems (via runoff and infiltration, Kass et al., 2005, Bouwer, 2000). A work package in the EU FP5 project SAFIR is dedicated to study the impact of wastewater irrigation on the soil-water-plant-product system. Its monitoring program comprises pathogens and inorganic pollutants, including both geogenic and potentially anthropogenic trace elements in the aim to better understand soil-irrigation water interactions. The SAFIR field study sites are found in China, Italy, Crete, and Serbia. A performance evaluation of SAFIR-specific treatment technology through the monitoring of waste water and irrigation water quality was made through waste water chemical and microbiological qualities, which were investigated upstream and downstream of the SAFIR specific treatment three times per season. Irrigation water transits through the uppermost soil decimetres to the crop roots. The latter will become, in the course of the irrigation season, the major sink of percolating water, together with evaporation. The water saving irrigation techniques used in SAFIR are surface and subsurface drip irrigation. The investigation of the solid soil phase concentrates on the root zone as main transit and storage compartment for pollutants and, eventually, pathogens. The initial soil quality was assessed through a sampling campaign before the onset of the first year irrigation; the soil quality has been monitored throughout three years under cultivation of tomatoes or potatoes. The plot layout for each of the study sites allows comparing different combinations of (1) water quality, including tap water as a reference, (2) irrigation techniques, and (3) irrigation strategies (including full irrigation, partial root drying, RDI). The replication of each of the combinations on three different plots takes into account the local variations of soil properties and allows a proper statistical treatment. Reactions of the infiltrating water with the soil solid phase are important for the solute cycling, temporary fixation and remobilisation of trace pollutants. The type of reaction (sorption, co-precipitation…) and the reactive mineral phases will also determine the availability of trace elements for the plant and determine the passage towards crops and products. Therefore it is important to assess the soil water quality, directly or indirectly. Direct measurements of soil water imply soil water sampling through an appropriate system; porous cups were installed on the Cretan, Italian and Chinese sites. Indirect evaluation of water-soil interactions can be obtained through sequential extractions. The combination of a variable input function (through diffuse pollution, irrigation, fertigation) and of variable MTE mobility in soils can be expected to lead to short term variations in soil metal concentrations even if such short term variations have been rarely investigated (Féder, 2001; Cary and Trolard, 2008). The sampling focused upon the fully irrigated plots given that the potential impact of irrigation water quality on soil and plant quality can be expected higher for fully irrigated soils compared to other irrigation strategies. Samples were taken within the soil volume of potential influence around each of the drip emitters. This volume varies depending on the nature of the soil and the irrigation system so that each site adopted a specific protocol. For all experiments, three sampling campaigns were scheduled for each irrigation season: at pre-planting, at the end of irrigation, at harvest. The geochemical evolution of soil properties over the 3 years shows significant variations in major and minor elements, especially trace metallic elements. It implies the role of the cultivated plant as a sink of elements which leads to direct loss of elements in the soil system. Bouwer, H., 2000. Groundwater problems caused by irrigation with sewage effluent. Journal of Environmental Health 63, 17-20. Cary L., Trolard F. (2008). Metal mobility in the ground water of a paddy field in Camargue (South eastern France). Journal of Geochemical Exploration 96/2-3 : 132-143. Féder, 2001. Dynamique des processus d'oxydo-reduction dans les sols hydromorphes, These de l'Universite Aix Marseille III. Kass, A. Gavrieli, I. Yechieli, Y. Vengosh A.and Starinsky, A., 2005. The impact of freshwater and wastewater irrigation on the chemistry of shallow groundwater: a case study from the Israeli Coastal Aquifer, Journal of Hydrology, 300, 314-331.

Columbia Plateau Basin and Fifteenmile Subbasin Water Rights Acquisitons; Oregon Water Trust Combined Work Plan, 2002-2003 Final Report.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Paulus, Fritz

2003-12-01

This is the Final Report submitted regarding Oregon Water Trust's Combined Work Plan for fiscal year 2003, with the contract period April 2002 to May 2003. Of this 12 month period, six month were spent concluding our work for the 2002 irrigation season and six months were spent preparing for the 2003 irrigation season. After this grant was completed, projects were finished with funding from the Columbia Basin Water Transactions Program. Many of the 2003 irrigation season successes began in the fall of 2002, when projects were researched and partnerships were developed. Trout Creek Ranch was one of the largemore » successes. During the 2003 irrigation season, 2.6 cfs was leased which led to a permanent instream transfer, protecting critical spawning habitat for summer steelhead in the Deschutes basin. Another success was the Walla Walla Lease Bank project. This project is an agreement between the OWT, the Walla Walla Irrigation District and 11 individual landowners. Through this single year lease, 7.9 cfs of water was legally protected in the Walla Walla River. The Vidando lease on Middle Fork John Day River was renewed for 2 more years, protecting 11.29 cfs. An innovative single year split-season lease was conducted with Voight on Standard Creek in the John Day basin to protect 4.93 cfs. Many other deals were conducted and the total was an impressive 50.43 cfs instream during 2003 and 9.39 cfs pending approval for the 2004 season. Included is a summary of the activities within the Fifteenmile subbasin and the Columbia Plateau basin by quarter and two tables. The summary of activities is broken down by objectives and quarters. The first summarizes the total cfs by type of lease or transfer. The second table lists all the projects by subbasin and provides project type, lease number, cfs, cost of acquisition, partners in the project and funding source.« less

Irrigation dose and plant density affect the volatile composition and sensory quality of dill (Anethum graveolens L.).

PubMed

El-Zaeddi, Hussein; Martínez-Tomé, Juan; Calín-Sánchez, Ángel; Burló, Francisco; Carbonell-Barrachina, Ángel A

2017-01-01

Two independent field experiments were carried out to investigate the influence of (i) three irrigation treatments (ID0 = 1585 m 3 ha -1 , considered as a control; ID1 = 1015 m 3 ha -1 ; and ID2 = 2180 m 3 ha -1 ) and (ii) three plant density treatments (PD0 = 5.56 plants m -2 , considered as a control; PD1 = 4.44 plants m -2 ; and PD2 = 7.41 plants m -2 ) on the production, volatile composition of essential oil, and sensory quality of dill. The highest plant yield was obtained with intermediate conditions of both irrigation dose (ID0) and plant density (PD0). The main compounds of the essential oil were α-phellandrene, dill ether and β-phellandrene. The highest irrigation dose (ID2) produced the highest concentrations of most of the main compounds: α-phellandrene (49.5 mg per 100 g), β-phellandrene (6.89 mg per 100 g) and limonene (2.49 mg per 100 g). A similar pattern was found for the highest plant density (PD2): α-phellandrene (71.0 mg per 100 g), dill ether (16.7 mg per 100 g) and β-phellandrene (9.70 mg per 100 g). The use of descriptive sensory analysis helped in reaching a final decision, and the dill plants with the highest sensory quality were those of the ID2 and PD0 treatments. The final recommendation is to use the irrigation dose ID2 and the plant density PD2 if the objective is to produce dill samples with the highest aromatic and sensory quality; however, if the only objective is to produce high amounts of dill, the best options are ID0 and PD0. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Opportunities for Automated Demand Response in California Agricultural Irrigation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Olsen, Daniel; Aghajanzadeh, Arian; McKane, Aimee

Pumping water for agricultural irrigation represents a significant share of California’s annual electricity use and peak demand. It also represents a large source of potential flexibility, as farms possess a form of storage in their wetted soil. By carefully modifying their irrigation schedules, growers can participate in demand response without adverse effects on their crops. This report describes the potential for participation in demand response and automated demand response by agricultural irrigators in California, as well as barriers to widespread participation. The report first describes the magnitude, timing, location, purpose, and manner of energy use in California. Typical on-­farm controlsmore » are discussed, as well as common impediments to participation in demand response and automated demand response programs. Case studies of demand response programs in California and across the country are reviewed, and their results along with overall California demand estimates are used to estimate statewide demand response potential. Finally, recommendations are made for future research that can enhance the understanding of demand response potential in this industry.« less

A regional field-based assessment of organic C sequestration and GHG balances in irrigated agriculture in Mediterranean semi-arid land

NASA Astrophysics Data System (ADS)

Virto, Inigo; Antón, Rodrigo; Arias, Nerea; Orcaray, Luis; Enrique, Alberto; Bescansa, Paloma

2016-04-01

In a context of global change and increasing food demand, agriculture faces the challenge of ensuring food security making a sustainable use of resources, especially arable land and water. This implies in many areas a transition towards agricultural systems with increased and stable productivity and a more efficient use of inputs. The introduction of irrigation is, within this framework, a widespread strategy. However, the C cycle and the net GHG emissions can be significantly affected by irrigation. The net effect of this change needs to be quantified at a regional scale. In the region of Navarra (NE Spain) more than 22,300 ha of rainfed agricultural land have been converted to irrigation in the last years, adding to the previous existing irrigated area of 70,000 ha. In this framework the project Life+ Regadiox (LIFE12 ENV/ES/000426, http://life-regadiox.es/) has the objective of evaluating the net GHG balances and atmospheric CO2 fixation rates of different management strategies in irrigated agriculture in the region. The project involved the identification of areas representative of the different pedocllimatic conditions in the region. This required soil and climate characterizations, and the design of a network of agricultural fields representative of the most common dryland and irrigation managements in these areas. This was done from available public datasets on climate and soil, and from soil pits especially sampled for this study. Two areas were then delimited, mostly based on their degree of aridity. Within each of those areas, fields were selected to allow for comparisons at three levels: (i) dryland vs irrigation, (ii) soil and crop management systems for non-permanent crops, and (iii) soil management strategies for permanent crops (namely olive orchards and vineyards). In a second step, the objective of this work was to quantify net SOC variations and GHG balances corresponding to the different managements identified in the previous step. These quantifications will allow for evaluating the most suitable strategies for developing sustainable irrigation agrosystems in the region. The quantification of SOC stocks was done within equivalent soil units in each area, and for each level of comparison. Soil organic C stocks were quantified using the area-frame randomized soil sampling protocol (Stolbovoy et al., 2007), in the tilled layer (0-30 cm). GHG balances were calculated from inputs information obtained from farmers, using tools developed by the regional agricultural research institute (INTIA), adapted to the local characteristics of agriculture. The results corresponding to the comparison between dryland and irrigated agrosystems showed differences both in terms of SOC storage and GHG balances in the two studied areas. Irrigated fields had significantly greater stocks of SOC on average, although net organic C storage was significantly affected by soil and crop type. Also, organic fertilization in dryland resulted in significantly more SOC stored in the soil. Net GHG balances were greatly affected by the type of crops and their management, in particular fertilization strategies. As a result, net balances in terms of GHG emissions and mitigation varied greatly among irrigated systems, and in comparison to dryland systems.

Effectiveness of root canal debris removal using passive ultrasound irrigation with chlorhexidine digluconate or sodium hypochlorite individually or in combination as irrigants.

PubMed

Ferreira, Rafael Brandao; Marchesan, Melissa Andreia; Silva-Sousa, Yara Teresinha; Sousa-Neto, Manoel

2008-07-01

The aim of this in vitro study was to evaluate the cleaning capacity of different auxiliary chemical substances energized with ultrasound in radicular dentin using morphologic analysis. Twenty-eight single-canal, mandibular incisors were prepared with the Hero 642 canal preparation system following the sequence: 25/12, 30/06, 35/02, and 40/02, 1 mm from the apex. The specimens were then divided into four groups of seven teeth. During biomechanical preparation the teeth were irrigated with 2 ml of distilled water between files. Each group of specimens (n=7) received a final irrigation with 100 ml of the following irrigants that were activated with ultrasound for 3 minutes: Group 1- distilled water; Group 2- 0.2% chlorhexidine digluconate (CHX); Group 3- 2.5% sodium hypochlorite (NaOCl); and Group 4-the filtrate obtained after combining 0.2% CHX and 2.5% NaOCl. The apical portions of the root canals from each group were then submitted to histological processing and analyzed using optical microscopy. Results showed statistical differences between the groups (p<0.01). Groups 1 and 2 (distilled water and 0.2% CHX respectively) were statistically similar in terms of a greater amount of debris, whereas 2.5% NaOCl and the filtrate were more efficient in removal of debris. There is no additional benefit in terms of debris removal from root canal walls by irrigating with the filtrate obtained from the combination of NaOCl and CHX when compared to using NaOCl alone. The findings of this study suggest the time and expense of preparing and using a combination of NaOCl and CHX is not warranted compared to using NaOCl alone for root canal irrigation.

Assessing hydrological drought risk for the irrigation sector in future climate scenarios: lessons learned from the Apulia case study (Italy)

NASA Astrophysics Data System (ADS)

Critto, Andrea; Torresan, Silvia; Ronco, Paolo; Zennaro, Federica; Santini, Monia; Trabucco, Antonio; Marcomini, Antonio

2016-04-01

Climate change is already affecting the frequency of drought events which may threaten the current stocks of water resources and thus the availability of freshwater for the irrigation. The achievement of a sustainable equilibrium between the availability of water resources and the irrigation demand is essentially related to the planning and implementation of evidence-based adaptation strategies and actions. In this sense, the improvement (of existing) and the development of (new) appropriate risk assessment methods and tools to evaluate the impact of drought events on irrigated crops is fundamental in order to assure that the agricultural yields are appropriate to meet the current and future food and market demand. This study evaluates the risk of hydrological drought on the irrigated agronomic compartment of Apulia, a semi-arid region in Southern Italy. We applied a stepwise Regional Risk Assessment (RRA) procedure, based on the consecutive analysis of hazards, exposure, vulnerability and risks, integrating the qualitative and quantitative available information. Future climate projections for the timeframes 2021-2050 and 2041-2070 were provided by COSMO-CLM under the radiative forcing RCP4.5 and RCP8.5. The run-off feeding the water stocks of the most important irrigation reservoirs in Apulia was then modeled with Arc-SWAT. Hence, the hazard analysis was carried out in order to estimate the degree of fulfillment of actual irrigation demand satisfied by water supply of different reservoirs in future scenarios. Vulnerability of exposed irrigated crops was evaluated depending on three factors accounting for crop yield variation vs water stress, water losses along the irrigation network, diversification of water supply. Resulting risk and vulnerability maps allowed: the identification of Reclamation Consortia at higher risk of not fulfilling their future irrigation demand (e.g. Capitanata Reclamation Consortia in RCP8.5 2041-2070 scenario); the ranking of most affected crops (e.g. fruit trees and vineyards); and finally, the characterization of vulnerability pattern of irrigation systems. Major achievements included the definition of a portfolio of science-driven adaptation strategies to reduce the risk pattern at both agronomic level (preferring crops with low vulnerability score, as olive groves) and at structural level (differentiating the water stocks and supplies and reducing losses and inefficiencies).

Nasal Irrigation for Chronic Rhinosinusitis and Fatigue in Patients with Gulf War Syndrome

DTIC Science & Technology

2013-07-01

materials (neti pots, xylitol , saline), and subject recruitment and enrollment. The human subjects research approval process required protocol submission...application submitted on 11/25/11 was also approved on 7/10/12. The company that provided xylitol (Danisco) is now owned by a private company (DuPont) a...regarding continuity of study as well as procurement and packaging of xylitol packets (sachets) for individual use by participants in the xylitol arm of

Efficient operation of a multi-purpose reservoir in Chile: Tradeoffs between irrigation and hydropower production

NASA Astrophysics Data System (ADS)

Gonzalez Cabrera, J. M., Sr.; Olivares, M. A.

2015-12-01

This study proposes a method to develop efficient operational policies for a reservoir the southern Chile. The main water uses in this system are hydropower and irrigation, with conflicting seasonal demands. The conflict between these two uses is currently managed through a so-called "irrigation agreement" which defines a series of operational conditions on the reservoir by restricting volumes used for power production depending on reservoir storage level. Other than that, the reservoir operation is driven by cost-minimization over the power grid. Recent evidence shows an increasing degree of conflict in this basin, which suggests that the static approach of irrigation agreements, might no longer be appropriate. Moreover, this agreement could be revised in light of decreased water availability. This problem poses a challenge related to the spatial scope of analysis. Thus, irrigation benefits are driven by decisions made within the basin, whereas hydropower benefits depend on the operation of the entire power grid. Exploring the tradeoffs between these two water uses involves modeling both scales. The proposed methodology integrates information from both a grid-wide power operations model and a basin-wide agro-economic model into a decision model for optimal reservoir operation. The first model, a hydrothermal coordination tool, schedules power production by each plant in the grid, and allows capturing technical and economic aspects to the operation of hydropower reservoirs. The agro-economic model incorporates economic features of irrigation in the basin, and allows obtaining irrigation water demand functions. Finally, the results of both models are integrated into a single model for optimal reservoir operation considering the tradeoffs between the two uses. The result of the joint operation of water resources, show a flexible coordination of uses, revealing the opportunity cost of irrigation, which it gives the possibility of negotiating transfers of water to hydropower in dry years, with the aim of obtaining greater benefits from water use in the basin

Behavior of Agricultural water users induced hydro-climatic cycle change in Heihe River Basin, in the northwest of china

NASA Astrophysics Data System (ADS)

Wu, F.; Deng, X.; Cai, X.; Zhang, X.; Zhang, Q.

2017-12-01

Water allocation unbalance is the most important driving force of ecological degradation in the Heihe River Basin, where it seems the lifeblood of environment and human society. Water commute complex and frequent in soil, atmosphere, surface and ground face. The balance analysis of Water's transformation based on the WRF (Weather Research Forecasting) and SWAT (Soil and Water Assessment Tool) simulations, puts forward the application of land governance in arid and semi-arid region. In this study, we designed an irrigation scheme using local field experiences and incorporated the irrigation scheme into WRF/Noah-MP model. Then, to test the effects of irrigation scheme on performance of WRF/Noah-MP model, we carried out two simulations with the Heihe watershed, Northwest China, as a case study area. Firstly, the irrigation simulation is meanly about 860 mm across all of 671 cropland grid cells within the Heihe watershed and gradually increases from about 500 mm nearby the foot of Qilian Mountain to the maximum about 1500 mm in the middle and lower reach of Heihe River. Both of regional mean value and spatial heterogeneity are close to ground measurements. Secondly, the irrigation simulation dramatically reduced the mean bias of specified humidity to -0.47 g kg-1 (accounting for 6.0% of observation) and RMSE of temperature to 0.47 °C, respectively, since the irrigation enhanced the surface latent heat and weakened sensible heat to atmosphere. Thirdly, Across the 8 agricultural sites, the correlation coefficient and RMSE increased from 0.75 to 0.80. Finally, we found the surface runoff will increase by 0.46% with SWAT model at irrigation months. Therefore, the irrigation may led to expansion of cultivated land through transformation from groundwater to surface water at some degree. Water authorities should strengthen the tough water management measures to implement measures of total quantity control and raise the efficiency of water resources.

Applications of remote sensing technology to U.S. Water resource management

NASA Technical Reports Server (NTRS)

Weber, J. D.

1982-01-01

Applications of Landsat data to assessing the available water supply in the U.S. for agricultural puposes as a program of the NASA Office of Space Science and Applications are described. Snow melt runoff predictions are performed with multitemporal Landsat imagery to measure the extent of mountain snow packs in the Rockies in order to produce stream flow forecast models. The data is used for decisions of which crops to plant, based on irrigation water which will be accessible in eleven western U.S. states. Imagery has tracked the growth of irrigated lands watered from the Ogallala aquifer in the central U.S., and is providing a data base for calculating the aquifer depletion rates. Studies are preceeding in temporally mapping the kinds of vegetation growing in the Suwannee Sound in Florida to monitor the intrusion of salt water, which would reduce the River's usefulness for irrigation. Finally, capabilities of the Thematic Mapper are reviewed.

D-Area Drip Irrigation-Phytoremediation Project: SRTC Final Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wilde, E.W.

2003-01-14

Groundwater in D-Area at the Savannah River Site (SRS) is contaminated with trichloroethylene (TCE) and by-products resulting from discharges of this organic solvent during past operations. Several potential clean-up strategies are being or have been investigated, including a novel drip irrigation-phytoremediation process that is the focus of the treatability study described in this report. The contaminated groundwater in D-Area occurs primarily at depths of 30 to 50 feet below ground surface, well below the depths that are typically penetrated by plant roots. The system investigated in this study involved pumping water from the contaminated aquifer and discharging the water intomore » overlying test plots below the surface using drip irrigation. The test plots contained pines, cottonwoods, or no vegetation (controls). The primary objective was to determine the overall effectiveness of the process for TCE removal and to elucidate the biotic and abiotic pathways for its removal.« less

Final Environmental Assessment for Effluent Irrigation of the Golf Course Holloman Air Force Base Otero County, New Mexico

DTIC Science & Technology

2008-10-01

availability of the EA was published in the Alamogordo Daily News, the Las Cruces Sun- Ne\\vs, the Ruidoso Ne\\vs, and the El Paso Times informing the public...Iviountairi View Drive Ruidoso , 1\\1M 88345 Gill M. Sorg President, Mesilla Valley Audubon Society PO Box 1645 Las Cruces, 1\\1-:;:\\1 88004 Final

Effect of 95% Ethanol as a Final Irrigant before Root Canal Obturation in Primary Teeth: An in vitro Study.

PubMed

Thiruvenkadam, G; Asokan, Sharath; John, Baby; Priya, Pr Geetha

2016-01-01

Successful obturation in the primary teeth demands complete dryness of the root canal system. The purpose of this study was to determine the effect of 95% ethanol as the final irrigant before root canal obturation in primary teeth. A total of 20 extracted primary mandibular canines were biomechanically prepared and pre-obturated volume of each tooth was assessed using spiral computed tomography (CT). The specimens were divided into two groups (n = 10): group 1, Metapex group; group 2, zinc oxide eugenol group. Each group was further divided randomly into two subgroups (n = 5): subgroup 1, canals were dried with 95% ethanol; subgroup 2, canals were blot dried with paper points with the last one appearing dry. All canals were obturated and the postobturated volume of each tooth was measured. The percentage of obturated volume (POV) was calculated using the formula: (postobturated volume/preobturated volume) × 100. The POV between the groups was statistically analyzed using Mann-Whitney test and Wilcoxon Signed rank test appropriately. Root canals that were dried with ethanol showed better obturation than using paper points alone and the difference was statistically significant in both group 1 (p < 0.001) and group 2 (p < 0.002). Drying of the root canal system with 95% ethanol can result in better obturation in the primary teeth. How to cite this article: Thiruvenkadam G, Asokan S, John B, Geetha Priya PR. Effect of 95% Ethanol as a Final Irrigant before Root Canal Obturation in Primary Teeth: An in vitro Study. Int J Clin Pediatr Dent 2016;9(1):21-24.

Efficacy of ultrasonic activation of NaOCl and orange oil in removing filling material from mesial canals of mandibular molars with and without isthmus

PubMed Central

Barreto, Mirela Sangoi; da Rosa, Ricardo Abreu; Santini, Manuela Favarin; Cavenago, Bruno Cavalini; Duarte, Marco Antônio Húngaro; Bier, Carlos Alexandre Souza; Só, Marcos Vinícius Reis

2016-01-01

ABSTRACT Objectives The aim of this study was to evaluate the volume of remaining filling material after passive ultrasonic irrigation (PUI) of sodium hypochlorite (NaOCl) and orange oil in mesial canals of mandibular molars, with and without isthmus. Material and Methods Thirty mesial roots of mandibular molars were divided according to the presence or absence of isthmus. Canals were prepared and filled (Micro-CT #1). Filling was removed using rotary instruments, and specimens were sub-divided into three groups according to the irrigation procedures: Conventional – conventional irrigation with NaOCl, PUI/NaOCl – PUI of NaOCl (three activations, 20 seconds each), and PUI/orange oil – PUI of orange oil (Micro-CT#2). Specimens were enlarged using the X2 and X3 ProTaper Next instruments and submitted to the same irrigation protocols (Micro-CT #3). Results No differences were found between the experimental groups in each stage of assessment (P>0.05). The volume of residual filling material was similar to those in Micro-CT #2 and Micro-CT #3, but lower than those observed in Micro-CT #1 (P<0.05). When groups were pooled according to the presence or absence of an isthmus, volume of residual filling material was higher in specimens presenting isthmus (P<0.05). Conclusions PUI of NaOCl or orange oil did not improve filling removal. Isthmus consists in an anatomical obstacle that impairs the removal of filling material. PMID:26200525

Water resources transfers through Chinese interprovincial and foreign food trade

PubMed Central

Dalin, Carole; Hanasaki, Naota; Qiu, Huanguang; Mauzerall, Denise L.; Rodriguez-Iturbe, Ignacio

2014-01-01

China’s water resources are under increasing pressure from socioeconomic development, diet shifts, and climate change. Agriculture still concentrates most of the national water withdrawal. Moreover, a spatial mismatch in water and arable land availability—with abundant agricultural land and little water resources in the north—increases water scarcity and results in virtual water transfers from drier to wetter regions through agricultural trade. We use a general equilibrium welfare model and linear programming optimization to model interprovincial food trade in China. We combine these trade flows with province-level estimates of commodities’ virtual water content to build China’s domestic and foreign virtual water trade network. We observe large variations in agricultural water-use efficiency among provinces. In addition, some provinces particularly rely on irrigation vs. rainwater. We analyze the virtual water flow patterns and the corresponding water savings. We find that this interprovincial network is highly connected and the flow distribution is relatively homogeneous. A significant share of water flows is from international imports (20%), which are dominated by soy (93%). We find that China’s domestic food trade is efficient in terms of rainwater but inefficient regarding irrigation, meaning that dry, irrigation-intensive provinces tend to export to wetter, less irrigation-intensive ones. Importantly, when incorporating foreign imports, China’s soy trade switches from an inefficient system to a particularly efficient one for saving water resources (20 km3/y irrigation water savings, 41 km3/y total). Finally, we identify specific provinces (e.g., Inner Mongolia) and products (e.g., corn) that show high potential for irrigation productivity improvements. PMID:24958864

Water resources transfers through Chinese interprovincial and foreign food trade.

PubMed

Dalin, Carole; Hanasaki, Naota; Qiu, Huanguang; Mauzerall, Denise L; Rodriguez-Iturbe, Ignacio

2014-07-08

China's water resources are under increasing pressure from socioeconomic development, diet shifts, and climate change. Agriculture still concentrates most of the national water withdrawal. Moreover, a spatial mismatch in water and arable land availability--with abundant agricultural land and little water resources in the north--increases water scarcity and results in virtual water transfers from drier to wetter regions through agricultural trade. We use a general equilibrium welfare model and linear programming optimization to model interprovincial food trade in China. We combine these trade flows with province-level estimates of commodities' virtual water content to build China's domestic and foreign virtual water trade network. We observe large variations in agricultural water-use efficiency among provinces. In addition, some provinces particularly rely on irrigation vs. rainwater. We analyze the virtual water flow patterns and the corresponding water savings. We find that this interprovincial network is highly connected and the flow distribution is relatively homogeneous. A significant share of water flows is from international imports (20%), which are dominated by soy (93%). We find that China's domestic food trade is efficient in terms of rainwater but inefficient regarding irrigation, meaning that dry, irrigation-intensive provinces tend to export to wetter, less irrigation-intensive ones. Importantly, when incorporating foreign imports, China's soy trade switches from an inefficient system to a particularly efficient one for saving water resources (20 km(3)/y irrigation water savings, 41 km(3)/y total). Finally, we identify specific provinces (e.g., Inner Mongolia) and products (e.g., corn) that show high potential for irrigation productivity improvements.

Effectiveness of chamomile (Matricaria recutita L.), MTAD and sodium hypochlorite irrigants on smear layer.

PubMed

Venkataram, V; Gokhale, S T; Kenchappa, M; Nagarajappa, R

2013-08-01

Endodontic success depends heavily on effective chemo-mechanical debridement of root canals through the use of instruments and irrigating solutions. To compare the effectiveness of chamomile hydroalcoholic extract, Biopure™ mixture of tetracycline isomer, acid and detergent (MTAD) and 2.5 % sodium hypochlorite (NaOCl) on removal of the smear layer. Randomised controlled trial. Thirty extracted single-rooted, primary human teeth were allocated at random into three experimental groups of 10 teeth each. For each tooth, the canal was prepared using the step-back technique. During instrumentation, 2 ml of the irrigant was used for at least 10 s after each file and 10 ml as a final flush for 2 min for chamomile and NaOCL irrigants. Whereas for MTAD, an initial rinse with 1.3 % NaOCl for a cumulated period of 20 min, and use of MTAD as the final rinse for a period of 5 min was followed. Longitudinal grooves were made on root segments, then split into two halves with a chisel, stored in 2.5 % glutaraldehyde solution and fixed in ethanol series. Specimens were examined for the smear layer according to Hulsmann et al. (Int Endod J 35:668-679, 2002) criteria using a scanning electron microscope. Kruskal-Wallis and Mann-Whitney U tests were used. The most effective result in removal of smear layer occurred with the use of MTAD, followed by chamomile extract. The chamomile extract was found to be significantly more effective than 2.5 % NaOCl solution which had only minor effects. The efficacy of chamomile to remove the smear layer was superior to 2.5 % NaOCl alone, but less effective than MTAD mixture.

Cleaning capacity of octenidine as root canal irrigant: A scanning electron microscopy study.

PubMed

Coaguila-Llerena, Hernán; Stefanini da Silva, Virgínia; Tanomaru-Filho, Mario; Guerreiro Tanomaru, Juliane Maria; Faria, Gisele

2018-06-01

The aim of this study was to assess the cleaning capacity of the octenidine hydrochloride (OCT) used as root canal irrigant by scanning electron microscopy (SEM) analysis. Sixty human unirradicular extracted teeth were randomly distributed in 6 groups (n = 10) according to irrigant solutions which were used during root canal preparation: G1, 0.1% OCT; G2, 2% chlorhexidine (CHX); G3, 2.5% sodium hypochlorite (NaOCl); G4, OCT + 17% ethylenediaminetetraacetic acid (EDTA); G5, 2.5% NaOCl + 17% EDTA and G6, distilled water. All specimens were instrumented with ProTaper system up to F4. Teeth were sectioned and prepared for SEM. The smear layer was evaluated using a 5-score system and the data were analyzed by Kruskal-Wallis and Dunn (α = 0.05). In all root canal thirds there was no significant difference between OCT, CHX, NaOCl, and water groups (p > .05), and these groups showed higher smear layer values than NaOCl + EDTA and OCT + EDTA groups (p < .05). There was no significant difference between NaOCl + EDTA and OCT + EDTA groups (p > .05). It was concluded that OCT used as a single root canal irrigant presented poor cleaning capacity and could be used in association with a final irrigation with EDTA to obtain smear layer removal. © 2018 Wiley Periodicals, Inc.

Economic and Environmental Assessment of Switchgrass Production on High-Fertility Soil and an Assessment of Anaerobic Digests as an Intermediate Market for Switchgrass

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rhykerd, Robert; Bierma, Thomas; Jin, Guang

2014-03-31

This project had two parts. Part 1 was an economic and environmental assessment of switchgrass production on high-fertility soil, and included an assessment of the effects of field irrigation with treated municipal wastewater (Studies A,C, and E in Final Agreement). Part 2 was an assessment of methods to enhance anaerobic digestion of switchgrass, and included evaluation of several other potential biomass feedstocks (Studies B and D in Final Agreement). Results from Part 1 demonstrated that switchgrass does not compete economically against a corn and soybean rotation on highly productive soils. All four varieties of switchgrass lost money while corn andmore » soybeans were profitable in all four years of this study. Breakeven prices for the four switchgrass varieties were calculated using production costs. The installation of a center pivot irrigation system had minimal impact on crop production and corn and soybean production remained profitable in the year the irrigator was installed. Because of drought and delays in installing the wastewater treatment plant, the irrigation system was not used until year 4 of this study. Therefore, longer term studies evaluating multiple year studies on the impact of irrigation on switchgrass are warranted. Results from irrigating with treated municipal wastewater showed no negative impact on soil quality. Results from Part 2 demonstrated that anaerobic digestion (AD) of switchgrass could be significantly enhanced using low heat (100oC) and mild caustic pretreatment without fine-grinding. Heat for pretreatment could be available from biogas-based combined heat and power (CHP) systems. In bench-top digesters simulating municipal wastewater treatment AD, methane production of coarse-ground switchgrass increased over 20-fold with pretreatment compared to untreated switchgrass. Bench-top studies simulating dairy-based AD also found high specific methane yield, but even untreated switchgrass digested reasonably well, indicating the value of AD micro-organisms acclimated to lignocellulosic feedstock. Similar results were found for corn stover. However, oak and maple leaves – representing common urban yard waste – were more resistant to digestion even with pretreatment. More pretreatment research is required before yard waste could become a significant feedstock for the low/medium-solids digesters common to municipal wastewater or livestock operations.« less

7 CFR 622.2 - Scope.

Code of Federal Regulations, 2010 CFR

2010-01-01

..., water quality management, ground water supply, agricultural pollution control, and other water management. (d) After a final plan for works of improvement is agreed upon between NRCS and the sponsors and... proper utilization of land, flood prevention, agricultural water management including irrigation and...

Removal of calcium hydroxide from Weine Type II systems using photon-induced photoacoustic streaming, passive ultrasonic, and needle irrigation: a microcomputed tomography study

PubMed Central

LLOYD, Adam; NAVARRETE, Geraldine; MARCHESAN, Melissa Andreia; CLEMENT, David

2016-01-01

ABSTRACT Objective This study compared the effectiveness of Er:YAG laser-activated irrigation (PIPS), passive ultrasonic irrigation (PUI) with EndoUltra and standard needle irrigation (SNI) in the removal of calcium hydroxide [Ca(OH)2] from the mesial roots of Weine Type II mandibular molars. Material and Methods Thirty mandibular molars were screened by µCT for the presence of mesial roots with complex intra-canal anatomy and a common apical foramen. The teeth were enlarged to a standardized 25/.06 preparation and filled with Ca(OH)2 paste. Specimens were divided into three groups (n=10) according to the technique used for Ca(OH)2 removal: PIPS, at 15 Hz and 20 mJ using a 9 mm long, 600 µm diameter tip; PUI using a 15/.02 tip; and SNI (30 Ga. side-vented needle). Equal volumes of 8.25% NaOCl and 17% EDTA were used in all groups. µCT was used to measure the initial amount of Ca(OH)2 present and to assess the residual volume of Ca(OH)2 following each irrigation protocol. Data were analyzed using Tukey HSD and Kruskal-Wallis tests (α=5%). Results The mean volume of Ca(OH)2 before removal was significantly higher in the coronal third than in the middle and apical third (p<0.001). Ca(OH)2 was similarly removed from the coronal and middle thirds with the three methods used (p>0.05). PIPS (median 0%; IQR: 0-0) showed significant higher Ca(OH)2 removal in the apical third than PUI (median 100%, IQR: 85-100) and SNI (median 47%; IQR: 16-72) (p<0.001). Conclusions PIPS laser-activation was more effective for the removal of Ca(OH)2 from mesial roots of mandibular molars with Weine Type II canal configurations than PUI with EndoUltra and SNI. PMID:28076457

A comparative evaluation of antibacterial effectiveness of sodium hypochlorite, Curcuma longa, and Camellia sinensis as irrigating solutions on isolated anaerobic bacteria from infected primary teeth.

PubMed

Dhariwal, Neha Shashikant; Hugar, Shivayogi M; Harakuni, Sheetal; Sogi, Suma; Assudani, Harsha G; Mistry, Laresh Naresh

2016-01-01

In endodontics, most of the commercial intra-canal medicaments have cytotoxic reactions and because of their inability to eliminate bacteria from dentinal tubules, recent medicine has turned its attention to the usage of biologic medication prepared from natural plants. The literature to testify the efficacy of natural alternatives in primary teeth is meagre and its effects as irrigating solutions need to be evaluated. To evaluate the antibacterial effectiveness of sodium hypochlorite, ethanolic extracts of Curcuma longa (turmeric) and Camellia sinensis (green tea) as irrigating solutions against the anaerobic bacteria isolated from the root canals of infected primary teeth. Thirty patients were selected based on the selected inclusion and exclusion criteria. Preoperative radiographs were taken. Rubber dam isolation and working length estimation were done, following which thirty samples were taken from the root canals of infected primary teeth using sterile absorbent paper points and transferred to tubes containing thioglycolate transport medium. The bacteria were then isolated using standard microbiological protocols and were subjected to antibiotic sensitivity testing using the three test irrigants. SPSS 18 software using Chi-square test was used for statistical analysis. The most commonly isolated bacteria included Porphyromonas sp., Bacteroides fragilis, Peptostreptococcus, and Staphylococcus aureus. Sodium hypochlorite and C. longa (turmeric) showed good antibacterial effect and were effective against most of the isolated bacteria. There was statistically significant difference in the antibacterial effect among the three tested groups (P < 0.001). The least effective was C. sinensis (green tea). The infected primary teeth almost always present with a polymicrobial structure with a wide variety of anaerobic bacteria. The chemo-mechanical preparation plays an important role in eradicating the population of predominant micro-organisms in treating these teeth with promising effects with the use of newer test irrigants while avoiding the side effects of sodium hypochlorite.

Microbial evaluation of traumatized teeth treated with triple antibiotic paste or calcium hydroxide with 2% chlorhexidine gel in pulp revascularization.

PubMed

Nagata, Juliana Y; Soares, Adriana J; Souza-Filho, Francisco J; Zaia, Alexandre A; Ferraz, Caio C R; Almeida, José F A; Gomes, Brenda P F A

2014-06-01

Revascularization outcome depends on microbial elimination because apical repair will not happen in the presence of infected tissues. This study evaluated the microbial composition of traumatized immature teeth and assessed their reduction during different stages of the revascularization procedures performed with 2 intracanal medicaments. Fifteen patients (7-17 years old) with immature teeth were submitted to the revascularization procedures; they were divided into 2 groups according to the intracanal medicament used: TAP group (n = 7), medicated with a triple antibiotic paste, and CHP group (n = 8), dressed with calcium hydroxide + 2% chlorhexidine gel. Samples were taken before any treatment (S1), after irrigation with 6% NaOCl (S2), after irrigation with 2% chlorhexidine (S3), after intracanal dressing (S4), and after 17% EDTA irrigation (S5). Cultivable bacteria recovered from the 5 stages were counted and identified by means of polymerase chain reaction assay (16S rRNA). Both groups had colony-forming unit counts significantly reduced after S2 (P < .05); however, no significant difference was found between the irrigants (S2 and S3, P = .99). No difference in bacteria counts was found between the intracanal medicaments used (P = .95). The most prevalent bacteria detected were Actinomyces naeslundii (66.67%), followed by Porphyromonas endodontalis, Parvimonas micra, and Fusobacterium nucleatum, which were detected in 33.34% of the root canals. An average of 2.13 species per canal was found, and no statistical correlation was observed between bacterial species and clinical/radiographic features. The microbial profile of infected immature teeth is similar to that of primarily infected permanent teeth. The greatest bacterial reduction was promoted by the irrigation solutions. The revascularization protocols that used the tested intracanal medicaments were efficient in reducing viable bacteria in necrotic immature teeth. Copyright © 2014 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Efficacy of NVC-422 against Staphylococcus aureus biofilms in a sheep biofilm model of sinusitis.

PubMed

Singhal, Deepti; Jekle, Andreas; Debabov, Dmitri; Wang, Lu; Khosrovi, Bez; Anderson, Mark; Foreman, Andrew; Wormald, Peter-John

2012-01-01

Bacterial biofilms are a major obstacle in management of recalcitrant chronic rhinosinusitis. NVC-422 is a potent, fast-acting, broad-spectrum, nonantibiotic, antimicrobial with a new mechanism of action effective against biofilm bacteria in in vitro conditions. The aim of this study was to investigate the safety and efficacy of NVC-422 as local antibiofilm treatment in a sheep model of rhinosinusitis. After accessing and occluding frontal sinus ostia in 24 merino sheep via staged endoscopic procedures, S. aureus clinical isolate was instilled in frontal sinuses. Following biofilm formation, ostial obstruction was removed and sinuses irrigated with 0.1% and 0.5% NVC-422 in 5 mM acetate isotonic saline at pH 4.0. Sheep were monitored for adverse effects and euthanized 24 hours after treatment. Frontal sinuses were assessed for infection and changes in mucosa after the treatment. S. aureus biofilms were identified with Baclight-confocal scanning microscopy protocol and the biofilm biomass assayed by applying the COMSTAT2 program to recorded image stacks. After 2 irrigations with 0.1% NVC-422, S. aureus biofilm biomass was reduced when compared to control sinuses (p = 0.0001), though this effect was variable in samples. NVC-422 0.5% solution irrigations reduced biofilm even more significantly and consistently over all samples (p < 0.0001). NVC-422 0.5% was also more effective than 0.1% NVC-422, vehicle control, and normal saline sinus irrigations in reducing biofilm biomass (p < 0.05 for all subgroups). No adverse events were observed in sheep after sinus irrigations with 0.1% and 0.5% NVC-422 solutions. NVC-422 is an effective topical agent against S. aureus biofilms, with dose-dependent efficacy in this animal model of biofilm-associated sinusitis. Copyright © 2012 American Rhinologic Society-American Academy of Otolaryngic Allergy, LLC.

[Yeast irrigation enhances the nutritional content in hydroponic green maize fodder].

PubMed

Bedolla-Torres, Martha H; Palacios Espinosa, Alejandro; Palacios, Oskar A; Choix, Francisco J; Ascencio Valle, Felipe de Jesús; López Aguilar, David R; Espinoza Villavicencio, José Luis; de Luna de la Peña, Rafael; Guillen Trujillo, Ariel; Avila Serrano, Narciso Y; Ortega Pérez, Ricardo

2015-01-01

The objective of this study was to evaluate the effect of irrigation with yeasts (Debaryomyces hansenii var. Fabry, Yarowia lipolytica YIBCS002, Yarowia lipolytica var. BCS and Candida pseudointermedia) on the final nutritional content of hydroponic green maize fodder (Zea Zea mays L.), applied at different fodder growth stages (1. seed-seedling stage, 2. seedling-plant 20cm, 3. during all the culture). Irrespective of the fodder growth stages at which they were applied, all yeasts tested enhanced the content of raw protein, lipids, ash, moisture and energy. The percentage of electrolytes (Na, K, Cl, sulphates, Ca and Mg) showed different responses depending on the kind of yeast applied; D. hansenii exhibited the highest increment in all electrolytes, except for phosphorous. We conclude that the addition of yeasts belonging to the genera Debaryomyces, Candida and Yarowia to the irrigation solution of hydroponic systems enhances the nutrient content of green fodder. This kind of irrigation can be applied to generate high commercial value cultures in limited spaces. Copyright © 2014 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

Combining eddy-covariance measurements and Penman-Monteith type models to estimate evapotranspiration of flooded and aerobic rice

NASA Astrophysics Data System (ADS)

Facchi, Arianna; Masseroni, Daniele; Gharsallah, Olfa; Gandolfi, Claudio

2014-05-01

Rice is of great importance both from a food supply point of view, since it represents the main food in the diet of over half the world's population, and from a water resources point of view, since it consumes almost 40% of the water amount used for irrigation. About 90% of global production takes place in Asia, while European production is quantitatively modest (about 3 million tons). However, Italy is the Europe's leading producer, with over half of total production, almost totally concentrated in a large traditional paddy rice area between the Lombardy and Piedmont regions, in the north-western part of the country. In this area, irrigation of rice is traditionally carried out by continuous flooding. The high water requirement of this irrigation regime encourages the introduction of water saving irrigation practices, as flood irrigation after sowing in dry soil and intermittent irrigation (aerobic rice). In the agricultural season 2013 an intense monitoring activity was conducted on three experimental fields located in the Padana plain (northern Italy) and characterized by different irrigation regimes (traditional flood irrigation, flood irrigation after sowing in dry soil, intermittent irrigation), with the aim of comparing the water balance terms for the three irrigation treatments. Actual evapotranspiration (ET) is one of the terms, but, unlike others water balance components, its field monitoring requires expensive instrumentation. This work explores the possibility of using only one eddy covariance system and Penman-Monteith (PM) type models for the determination of ET fluxes for the three irrigation regimes. An eddy covariance station was installed on the levee between the traditional flooded and the aerobic rice fields, to contemporaneously monitor the ET fluxes from this two treatments as a function of the wind direction. A detailed footprint analysis was conducted - through the application of three different analytical models - to determine the position and the size of the footprint area at each monitoring time step (30-min). Two sets of half-hourly ET values, each one concerning one of the two treatments, were therefore obtained, each one comprising about 10-15% of the daytime time steps over the whole agricultural season. To confirm the reliability of the measured ET fluxes, the energy balance closure was computed for the two fields and resulted in an imbalance lower than 10% for both the irrigation treatments. The two eddy covariance data-sets were then used to calibrate three Penman-Monteith type models: one for the estimation of the rice crop transpiration (T), the second for the soil evaporation (ES), and the third for the evaporation from the water covering the soil in the case of flooded rice fields (EH20). Models were implemented using the available agro-meteorological data detected over the rice canopies and the periodically measured values of crop parameters (leaf area index, crop height). Finally, the calibrated models were used to compute the complete hourly ET data series for the three irrigation regimes.

Study on grain quality forecasting method and indicators by using hyperspectral data in wheat

NASA Astrophysics Data System (ADS)

Huang, Wenjiang; Wang, Jihua; Liu, Liangyun; Wang, Zhijie; Tan, Changwei; Song, Xiaoyu; Wang, Jingdi

2005-01-01

Field experiments were conducted to examine the influence factors of cultivar, nitrogen application and irrigation on grain protein content, gluten content and grain hardness in three winter wheat cultivars under four levels of nitrogen and irrigation treatments. Firstly, the influence of cultivars and environment factors on grain quality were studied, the effective factors were cultivars, irrigation, fertilization, et al. Secondly, total nitrogen content around winter wheat anthesis stage was proved to be significant correlative with grain protein content, and spectral vegetation index significantly correlated to total nitrogen content around anthesis stage were the potential indicators for grain protein content. Accumulation of total nitrogen content and its transfer to grain is the physical link to produce the final grain protein, and total nitrogen content at anthesis stage was proved to be an indicator of final grain protein content. The selected normalized photochemical reflectance index (NPRI) was proved to be able to predict of grain protein content on the close correlation between the ratio of total carotenoid to chlorophyll a and total nitrogen content. The method contributes towards developing optimal procedures for predicting wheat grain quality through analysis of their canopy reflected spectrum at anthesis stage. Regression equations were established for forecasting grain protein and dry gluten content by total nitrogen content at anthesis stage, so it is feasible for forecasting grain quality by establishing correlation equations between biochemical constitutes and canopy reflected spectrum.

Evaluation of final irrigation regimens with maleic acid for smear layer removal and wettability of root canal sealer.

PubMed

Ballal, Nidambur Vasudev; Ferrer-Luque, Carmen Maria; Sona, Mrunali; Prabhu, K Narayan; Arias-Moliz, Teresa; Baca, Pilar

2018-04-01

To evaluate the smear layer removal and wettability of AH Plus sealer on root canal dentin treated with MA (maleic acid), MA + CTR (cetrimide) and MA + CTR + CHX (chlorhexidine) as final irrigating regimens. For smear layer removal, 40 teeth were instrumented to size F4 and divided into four groups: (1) 7% MA, (2) 7% MA + 0.2% CTR, (3) 7% MA + 0.2% CTR + 2% CHX, (4) distilled water (control). After irrigation, teeth were subjected to SEM analysis. For contact angle analysis, 20 teeth were split longitudinally and divided into four groups similar to smear layer analysis. AH plus sealer was placed on each specimen and contact angle was analysed. In both smear layer (p = .393) and contact angle analysis (p = .961), there was no significant difference between the groups MA and MA + CTR. However, MA + CTR + CHX removed smear layer less effectively (p = .023) and increased the contact angle of the sealer (p = .005). In smear layer analysis, specimens in negative control group were heavily smeared. In case of contact angle analysis, samples in the control group had least contact angle. MA alone or in combination with CTR removed smear layer effectively and increased the wettability of AH plus sealer to root canal dentin.

Application of a nanofibrous composite membrane to the fertilizer-driven forward osmosis process for irrigation water use.

PubMed

An, Hee-Kyung; Lee, Chang-Gu; Park, Seong-Jik

2017-11-01

In this study, we fabricated a nanofibrous composite (NFC) membrane as a substrate to produce forward osmosis (FO) membranes, and we also assessed the use of liquid fertilizer as a draw solution for the FO process in order to produce agricultural irrigation water. Commercial cellulose triacetate (CTA) and thin-film composite (TFC) FO membranes were included in this study. Under FO tests, the NFC, CTA, and TFC membranes achieved initial osmotic water flux values of 35.31, 6.85, and 3.31 L/m 2 ·h and final osmotic water flux values of 12.62, 6.31, and 3.85 L/m 2  h, respectively. The reason for the high osmotic water flux of the NFC membrane is because its nanofiber layer has low tortuosity, high porosity, and a low thickness, resulting in a reduction in the internal concentration polarization phenomenon. When liquid fertilizer was used as the draw solution, the water flux values in the FO experiments for the NFC, CTA, and TFC membranes were 15.54, 5.46, and 2.54 L/m 2  h. Finally, our results revealed that the FO process using liquid fertilizer as a draw solution can be applied to produce agricultural irrigation water from brackish water and the newly fabricated NFC membrane can be applied to the FO process.

Regenerative endodontics--biologically-based treatment for immature permanent teeth: a case report and review of the literature.

PubMed

Thomson, A; Kahler, B

2010-12-01

A paradigm shift in the treatment of immature, necrotic teeth has occurred with biologically-based principles and regenerative endodontic protocols replacing traditional 'apexification' procedures. Preliminary research suggests that stem and progenitor cells from the pulp and/or periodontium contribute to continued root development when regenerative procedures are followed. A mandibular premolar tooth with a chronic periapical abscess was irrigated with sodium hypochlorite with minimal instrumentation and then dressed with tri-antibiotic paste consisting of ciprofloxacin, metronidazole and amoxicillin. At a subsequent visit a blood clot was evoked in the canal by irritating periapical tissues and the canal sealed with mineral trioxide aggregate, glass ionomer cement and composite resin. Resolution of apical periodontitis and the draining sinus, continued root maturation and apical closure occurred over an 18-month period. The tooth became responsive to pulp sensibility testing. It is important that dentists recognize the potential of regenerative endodontics in the treatment of necrotic, immature teeth. Initial management should involve irrigation with sodium hypochlorite only. Intra-canal medicaments, such as calcium hydroxide, are contraindicated as they inhibit further root growth. This report uses a variation of the tri-antibiotic paste currently recommended for regenerative procedures that avoided the discolouration of the crown associated with current protocols. Regenerative endodontics with continued root growth may reduce the risk of fracture and premature tooth loss associated with traditional 'apexification' procedures where the root remains thin and weak. © 2010 Australian Dental Association.

Cierny-Mader Type III chronic osteomyelitis: the results of patients treated with debridement, irrigation, vancomycin beads and systemic antibiotics

PubMed Central

Karaduman, Mert

2007-01-01

Cierny-Mader (C-M) Type III osteomyelitis is defined as a localised lesion with both medullary and cortical involvement that is stable mechanically after debridement. The treatment of C-M Type III osteomyelitisis is difficult and requires a precise protocol to achieve a disease-free long-term follow-up. We report here the results of our study on 26 patients (19 men and 7 women; average age: 34.7 years) with C-M Type III osteomylelitis who were treated with radical debridement, irrigation, vancomycin-impregnated custom-made beads and culture-specific systemic antibiotics. Those patients with metaphyseal involvement were treated with deroofing of the cortex and debridement by means of a “trough” (16 patients); those with diaphyseal involvement were treated with both intramedullary reaming and debridement from a trough (ten patients). Antibiotic cement rods were used as an additional therapy in five patients with diaphyseal involvement. Recurrence developed in three patients and was attributed to inadequate debridement; all three patients were treated again in the same manner with success. The mean follow-up is currently 3.6 years (range: 2–6 years). All of the patients have normal clinical, radiographic and laboratory parameters, and all are ambulatory and have returned to their pretreatment level of activity or better. We conclude that C-M Type III chronic osteomyelitis can be safely treated with this protocol. PMID:17375299

A Solar Energy Powered Autonomous Wireless Actuator Node for Irrigation Systems

PubMed Central

Lajara, Rafael; Alberola, Jorge; Pelegrí-Sebastiá, José

2011-01-01

The design of a fully autonomous and wireless actuator node (“wEcoValve mote”) based on the IEEE 802.15.4 standard is presented. The system allows remote control (open/close) of a 3-lead magnetic latch solenoid, commonly used in drip irrigation systems in applications such as agricultural areas, greenhouses, gardens, etc. The very low power consumption of the system in conjunction with the low power consumption of the valve, only when switching positions, allows the system to be solar powered, thus eliminating the need of wires and facilitating its deployment. By using supercapacitors recharged from a specifically designed solar power module, the need to replace batteries is also eliminated and the system is completely autonomous and maintenance free. The “wEcoValve mote” firmware is based on a synchronous protocol that allows a bidirectional communication with a latency optimized for real-time work, with a synchronization time between nodes of 4 s, thus achieving a power consumption average of 2.9 mW. PMID:22346580

A solar energy powered autonomous wireless actuator node for irrigation systems.

PubMed

Lajara, Rafael; Alberola, Jorge; Pelegrí-Sebastiá, José

2011-01-01

The design of a fully autonomous and wireless actuator node ("wEcoValve mote") based on the IEEE 802.15.4 standard is presented. The system allows remote control (open/close) of a 3-lead magnetic latch solenoid, commonly used in drip irrigation systems in applications such as agricultural areas, greenhouses, gardens, etc. The very low power consumption of the system in conjunction with the low power consumption of the valve, only when switching positions, allows the system to be solar powered, thus eliminating the need of wires and facilitating its deployment. By using supercapacitors recharged from a specifically designed solar power module, the need to replace batteries is also eliminated and the system is completely autonomous and maintenance free. The "wEcoValve mote" firmware is based on a synchronous protocol that allows a bidirectional communication with a latency optimized for real-time work, with a synchronization time between nodes of 4 s, thus achieving a power consumption average of 2.9 mW.

Spatial Estimation of Evapotranspiration in an Irrigated Semi-arid Region Using LSMs Driven by Remote Sensing Data.

NASA Astrophysics Data System (ADS)

Etchanchu, J.; Delogu, E.; Saadi, S.; Chebbi, W.; Trapon, D.; Rivalland, V.; Boulet, G.; Boone, A. A.; Fanise, P.; Mougenot, B.; LE Dantec, V.

2017-12-01

Evapotranspiration and sensible-latent heat flux partition are important decision critera to manage crops, detect water stress and plan irrigation, particularly in a semi-arid context. Nowadays, remote sensing information (at medium -MODIS- and high resolution -LANDSAT, SPOT-) allows us to spatially estimate the different terms of the energy balance at daily and infra-daily time step through various approaches, either by forcing data in an energy balance model (EVASPA, Gallego-Elvira et al., 2013, and SPARSE, Boulet et al., 2015) or data assimilation in coupled water/energy balance models (SURFEX-ISBA, Noilhan et Planton, 1989). However, these different methods of flux estimations still require an evaluation through comparison to in-situ measurements and inter-comparison.The area selected for this study is the Kairouan agricultural plain, a semi-arid region in central Tunisia. Different flux datasets were acquired over two years, on an extensive rainfed oliveyard with very low vegetation cover, and on irrigated and rainfed wheat plots. In the same time, a third dataset has been acquired over a complex agricultural landscape with an eXtra-Large Aperture Scintillometer (XLAS) set-up on a 4 km transect.First, EC fluxes from towers are compared to the different model simulations at plot scale. Then a spatial comparison with retrievals of sensible and latent heat fluxes from XLAS is performed which allows to take into account the heterogeneity of the landscape (mix of wheat, irrigated oliveyards and bare soil). Effects on irrigation scenarios, through an automatic irrigation triggering method are tested and discussed. Finally, we cross-compare the different modeling approaches.We tackle the various issues: the accuracy of the measurements, the temporal frequency of remote sensing data, and the difficulty to calibrate the models.

[Regulation effect of water storage in deeper soil layers on root physiological characteristics and leaf photosynthetic traits of cotton with drip irrigation under mulch].

PubMed

Luo, Hong-Hai; Zhang, Hong-Zhi; Du, Ming-Wei; Huang, Jian-Jun; Zhang, Ya-Li; Zhang, Wang-Feng

2009-06-01

A soil column culture experiment was conducted under the ecological and climatic conditions of Xinjiang to study the effects of water storage in deeper (> 60 cm) soil layers on the root physiological characteristics and leaf photosynthetic traits of cotton variety Xinluzao 13. Two treatments were installed, i.e., well-watered and no watering. The moisture content in plough layer was controlled at 70% +/- 5% and 55% +/- 5% of field capacity by drip irrigation under mulch during growth season. It was shown that the water storage in deeper soil layers enhanced the SOD activity and the vigor of cotton root, and increased the water use efficiency of plant as well as the leaf water potential, chlorophyll content, and net photosynthesis rate, which finally led to a higher yield of seed cotton and higher water use efficiency. Under well-watered condition and when the moisture content in plough layer was maintained at 55% of field capacity, the senescence of roots in middle and lower soil layers was slower, and the higher root vigor compensated the negative effects of impaired photosynthesis caused by water deficit to some extent. The yield of seed cotton was lower when the moisture content in plough layer was maintained at 55% of field capacity than at 70% of field capacity, but no significant difference was observed in the water use efficiency. Our results emphasized the importance of pre-sowing irrigation in winter or in spring to increase the water storage of deeper soil layers. In addition, proper cultivation practices and less frequent drip irrigation (longer intervals between successive rounds of irrigation) were also essential for conserving irrigation water and achieving higher yield.

Reconstructing the duty of water: a study of emergent norms in socio-hydrology

NASA Astrophysics Data System (ADS)

Wescoat, J. L., Jr.

2013-12-01

This paper assesses the changing norms of water use known as the duty of water. It is a case study in historical socio-hydrology, or more precisely the history of socio-hydrologic ideas, a line of research that is useful for interpreting and anticipating changing social values with respect to water. The duty of water is currently defined as the amount of water reasonably required to irrigate a substantial crop with careful management and without waste on a given tract of land. The historical section of the paper traces this concept back to late 18th century analysis of steam engine efficiencies for mine dewatering in Britain. A half-century later, British irrigation engineers fundamentally altered the concept of duty to plan large-scale canal irrigation systems in northern India at an average duty of 218 acres per cubic foot per second (cfs). They justified this extensive irrigation standard (i.e., low water application rate over large areas) with a suite of social values that linked famine prevention with revenue generation and territorial control. The duty of water concept in this context articulated a form of political power, as did related irrigation engineering concepts such as "command" and "regime". Several decades later irrigation engineers in the western US adapted the duty of water concept to a different socio-hydrologic system and norms, using it to establish minimum standards for private water rights appropriation (e.g., only 40 to 80 acres per cfs). While both concepts of duty addressed socio-economic values associated with irrigation, the western US linked duty with justifications for, and limits of, water ownership. The final sections show that while the duty of water concept has been eclipsed in practice by other measures, standards, and values of water use efficiency, it has continuing relevance for examining ethical duties and for anticipating, if not predicting, emerging social values with respect to water.

Comparative Analysis of Dentinal Erosion after Passive Ultrasonic Irrigation versus Irrigation with Reciprocating Activation: An Environmental Scanning Electron Study.

PubMed

Simezo, Ana Paula; da Silveira Bueno, Carlos Eduardo; Cunha, Rodrigo Sanches; Pelegrine, Rina Andrea; Rocha, Daniel Guimarães Pedro; de Martin, Alexandre Sigrist; Kato, Augusto Shoji

2017-01-01

The aim of this study was to assess ex vivo the erosive effects of passive ultrasonic irrigation versus irrigation with reciprocating activation on the dentinal surface of the root canal at 3 predetermined levels using environmental scanning electron microscopy. Ten roots of mandibular premolars were prepared using the ProTaper Universal system (Dentsply Maillefer, Ballaigues, Switzerland). The specimens were embedded in flasks cleaved longitudinally, and indentations were made 3.0, 6.0, and 9.0 mm from the apex. The specimens in the control group (n = 10) were cleaned in an ultrasonic bath containing 2.5% sodium hypochlorite and 17% EDTA and then dried. Then, environmental scanning electron microscopic images were obtained at magnification × 800. The specimens were then reassembled in their flasks, and the NaOCl and EDTA solutions were activated according to the conditions established for the experimental groups (ie, the passive ultrasonic irrigation group [n = 5] and the EasyClean (Easy Equipamentos Odontológicos, Belo Horizonte, MG, Brazil) group, irrigation with reciprocating activation with the EasyClean instrument [n = 5]). The specimens of both experimental groups were analyzed in the same manner as in the control group. Analysis of the dentinal surface topography was conducted using the 3D Roughness Reconstruction program (Phenom-World BV, Eindhoven, the Netherlands) as a means for assessing erosion. The data were evaluated by means of the Kruskal-Wallis, Student-Newman-Keuls, and Mann-Whitney tests. In the EasyClean group, the degree of dentinal erosion at 3.0 mm was significantly higher than at 9.0 mm. In the other comparisons, there was no statistically significant difference (P < .05). The final irrigation techniques tested were equivalent in relation to the degree of erosion caused to the dentinal surface. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Smear layer removal and canal cleanliness using different irrigation systems (EndoActivator, EndoVac, and passive ultrasonic irrigation): field emission scanning electron microscopic evaluation in an in vitro study.

PubMed

Mancini, Manuele; Cerroni, Loredana; Iorio, Lorenzo; Armellin, Emiliano; Conte, Gabriele; Cianconi, Luigi

2013-11-01

The purpose of this study was to evaluate the effectiveness of different irrigating methods in removing the smear layer at 1, 3, 5, and 8 mm from the apex of endodontic canals. Sixty-five extracted single-rooted human mandibular premolars were decoronated to a standardized length of 16 mm. Specimens were shaped to ProTaper F4 (Dentsply Maillefer, Ballaigues, Switzerland) and irrigated with 5.25% NaOCl at 37°C. Teeth were divided into 5 groups (2 control groups [n = 10] and 3 test groups [n = 15]) according to the final irrigant activation/delivering technique (ie, sonic irrigation, passive ultrasonic irrigation [PUI], or apical negative pressure). Root canals were then split longitudinally and observed by field emission scanning electron microscopy. The presence of debris and a smear layer at 1, 3, 5, and 8 mm from the apex was evaluated. Scores were analyzed by Kruskal-Wallis and Mann-Whitney U tests. The EndoActivator System (Dentsply Tulsa Dental Specialties, Tulsa, OK) was significantly more efficient than PUI and the control groups in removing the smear layer at 3, 5, and 8 mm from the apex. The EndoVac System (Discus Dental, Culver City, CA) removed statistically significantly more smear layer than all groups at 1, 3, 5, and 8 mm from the apex. At 5 and 8 mm from the apex, PUI and the EndoVac did not differ statistically significantly, but both performed statistically better than the control groups. In our study, none of the activation/delivery systems completely removed the smear layer from the endodontic dentine walls; nevertheless, the EndoActivator and EndoVac showed the best results at 3, 5, and 8 mm (EndoActivator) and 1, 3, 5, and 8 mm (EndoVac) from the apex. Copyright © 2013 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

An integrated framework to assess adaptation options to climate change impacts in an irrigated basin in Central North Chile

NASA Astrophysics Data System (ADS)

Vicuna, S.; Melo, O.; Meza, F. J.; Alvarez, P.; Maureira, F.; Sanchez, A.; Tapia, A.; Cortes, M.; Dale, L. L.

2013-12-01

Future climate conditions could potentially affect water supply and demand on water basins throughout the world but especially on snowmelt-driven agriculture oriented basins that can be found throughout central Chile. Increasing temperature and reducing precipitation will affect both the magnitude and timing of water supply this part of the world. Different adaptation strategies could be implemented to reduce the impacts of such scenarios. Some could be incorporated as planned policies decided at the basin or Water Use Organization levels. Examples include changing large scale irrigation infrastructure (reservoirs and main channels) either physically or its operation. Complementing these strategies it is reasonable to think that at a disaggregated level, farmers would also react (adapt) to these new conditions using a mix of options to either modify their patterns of consumption (irrigation efficiency, crop mix, crop area reduction), increase their ability to access new sources of water (groundwater, water markets) or finally compensate their expected losses (insurance). We present a modeling framework developed to represent these issues using as a case study the Limarí basin located in Central Chile. This basin is a renowned example of how the development of reservoirs and irrigation infrastructure can reduce climate vulnerabilities allowing the economic development of a basin. Farmers in this basin tackle climate variability by adopting different strategies that depend first on the reservoir water volume allocation rule, on the type and size of investment they have at their farms and finally their potential access to water markets and other water supplies options. The framework developed can be used to study these strategies under current and future climate scenarios. The cornerstone of the framework is an hydrology and water resources model developed on the WEAP platform. This model is able to reproduce the large scale hydrologic features of the basin such as snowmelt hydrology, reservoir operation and groundwater dynamics. Crop yield under different water irrigation patterns have been inferred using a calibrated Cropsyst model. These crop yields together with user association irrigation constraints are used in a GAMS optimization model embedded dynamically in WEAP in order to obtain every year decisions on crop mix (including fallow land), irrigation patterns and participation in the spot water market. The GAMS optimization model has been calibrated using annual crop mix time series derived using a combination of sources of information ranging from different type of census plus satellite images. The resulting modeling platform is able to simulate under historic and future climate scenarios water availability in different locations of the basin with associated crop yield and economic consequences. The platform also allows the implementation of autonomous and planned adaptation strategies that could reduce the impacts of climate variability and climate change.

SHALLOW GROUNDWATER USE BY ALFALFA

USDA-ARS?s Scientific Manuscript database

One proposal for drainage water disposal is to reuse drainage water for irrigation of salt tolerant crops until the volume has been reduced sufficiently to enable final disposal by evaporation. Part of this concept of serial biological concentration requires in-situ crop water reuse from shallow gr...

A Guide to Energy Savings - For the Vegetable Producer.

ERIC Educational Resources Information Center

Wynn, N. A.

This booklet gives a brief overview of energy use patterns in vegetable production and gives examples of cutting the cost of energy in fertilization, weed management, insect pest management, irrigation, harvesting, use of equipment, and greenhouses. Finally, energy use recordkeeping is discussed. (BB)

Membrane Signaling Induced by High Doses of Ionizing Radiation in the Endothelial Compartment. Relevance in Radiation Toxicity

PubMed Central

Corre, Isabelle; Guillonneau, Maëva; Paris, François

2013-01-01

Tumor areas can now be very precisely delimited thanks to technical progress in imaging and ballistics. This has also led to the development of novel radiotherapy protocols, delivering higher doses of ionizing radiation directly to cancer cells. Despite this, radiation toxicity in healthy tissue remains a major issue, particularly with dose-escalation in these new protocols. Acute and late tissue damage following irradiation have both been linked to the endothelium irrigating normal tissues. The molecular mechanisms involved in the endothelial response to high doses of radiation are associated with signaling from the plasma membrane, mainly via the acid sphingomyelinase/ceramide pathway. This review describes this signaling pathway and discusses the relevance of targeting endothelial signaling to protect healthy tissues from the deleterious effects of high doses of radiation. PMID:24252908

Global irrigated area map (GIAM), derived from remote sensing, for the end of the last millennium

USGS Publications Warehouse

Thenkabail, P.S.; Biradar, C.M.; Noojipady, P.; Dheeravath, V.; Li, Y.; Velpuri, M.; Gumma, M.; Gangalakunta, O.R.P.; Turral, H.; Cai, X.; Vithanage, J.; Schull, M.A.; Dutta, R.

2009-01-01

A Global Irrigated Area Map (GIAM) has been produced for the end of the last millennium using multiple satellite sensor, secondary, Google Earth and groundtruth data. The data included: (a) Advanced Very High Resolution Radiometer (AVHRR) 3-band and Normalized Difference Vegetation Index (NDVI) 10 km monthly time-series for 1997-1999, (b) Syste me pour l'Observation de la Terre Vegetation (SPOT VGT) NDVI 1 km monthly time series for 1999, (c) East Anglia University Climate Research Unit (CRU) rainfall 50km monthly time series for 1961-2000, (d) Global 30 Arc-Second Elevation Data Set (GTOPO30) 1 km digital elevation data of the World, (e) Japanese Earth Resources Satellite-1 Synthetic Aperture Radar (JERS-1 SAR) data for the rain forests during two seasons in 1996 and (f) University of Maryland Global Tree Cover 1 km data for 1992-1993. A single mega-file data-cube (MFDC) of the World with 159 layers, akin to hyperspectral data, was composed by re-sampling different data types into a common 1 km resolution. The MFDC was segmented based on elevation, temperature and precipitation zones. Classification was performed on the segments. Quantitative spectral matching techniques (SMTs) used in hyperspectral data analysis were adopted to group class spectra derived from unsupervised classification and match them with ideal or target spectra. A rigorous class identification and labelling process involved the use of: (a) space-time spiral curve (ST-SC) plots, (b) brightness-greenness-wetness (BGW) plots, (c) time series NDVI plots, (d) Google Earth very-high-resolution imagery (VHRI) 'zoom-in views' in over 11 000 locations, (e) groundtruth data broadly sourced from the degree confluence project (3 864 sample locations) and from the GIAM project (1 790 sample locations), (f) high-resolution Landsat-ETM+ Geocover 150m mosaic of the World and (g) secondary data (e.g. national and global land use and land cover data). Mixed classes were resolved based on decision tree algorithms and spatial modelling, and when that did not work, the problem class was used to mask and re-classify the MDFC, and the class identification and labelling protocol repeated. The sub-pixel area (SPA) calculations were performed by multiplying full-pixel areas (FPAs) with irrigated area fractions (IAFs) for every class. A 28 class GIAM was produced and the area statistics reported as: (a) annualized irrigated areas (AIAs), which consider intensity of irrigation (i.e. sum of irrigated areas from different seasons in a year plus continuous year-round irrigation or gross irrigated areas), and (b) total area available for irrigation (TAAI), which does not consider intensity of irrigation (i.e. irrigated areas at any given point of time plus the areas left fallow but 'equipped for irrigation' at the same point of time or net irrigated areas). The AIA of the World at the end of the last millennium was 467 million hectares (Mha), which is sum of the non-overlapping areas of: (a) 252 Mha from season one, (b) 174 Mha from season two and (c) 41 Mha from continuous year-round crops. The TAAI at the end of the last millennium was 399 Mha. The distribution of irrigated areas is highly skewed amongst continents and countries. Asia accounts for 79% (370 Mha) of all AIAs, followed by Europe (7%) and North America (7%). Three continents, South America (4%), Africa (2%) and Australia (1%), have a very low proportion of the global irrigation. The GIAM had an accuracy of 79-91%, with errors of omission not exceeding 21%, and the errors of commission not exceeding 23%. The GIAM statistics were also compared with: (a) the United Nations Food and Agricultural Organization (FAO) and University of Frankfurt (UF) derived irrigated areas and (b) national census data for India. The relationships and causes of differences are discussed in detail. The GIAM products are made available through a web portal (http://www.iwmigiam.org). ?? 2009 Taylor & Francis.

Reconstructing the duty of water: a study of emergent norms in socio-hydrology

NASA Astrophysics Data System (ADS)

Wescoat, J. L., Jr.

2013-06-01

This paper assesses changing norms of water use known as the duty of water. It is a case study in historical socio-hydrology, a line of research useful for anticipating changing social values with respect to water. The duty of water is currently defined as the amount of water reasonably required to irrigate a substantial crop with careful management and without waste on a given tract of land. The historical section of the paper traces this concept back to late-18th century analysis of steam engine efficiencies for mine dewatering in Britain. A half-century later, British irrigation engineers fundamentally altered the concept of duty to plan large-scale canal irrigation systems in northern India at an average duty of 218 acres per cubic foot per second (cfs). They justified this extensive irrigation standard (i.e., low water application rate over large areas) with a suite of social values that linked famine prevention with revenue generation and territorial control. Several decades later irrigation engineers in the western US adapted the duty of water concept to a different socio-hydrologic system and norms, using it to establish minimum standards for water rights appropriation (e.g., only 40 to 80 acres per cfs). The final section shows that while the duty of water concept has now been eclipsed by other measures and standards of water efficiency, it may have continuing relevance for anticipating if not predicting emerging social values with respect to water.

Assessing the Risk of Aquifer Salinization in a Large-Scale Coastal Irrigation Scheme in Southern Italy

NASA Astrophysics Data System (ADS)

Zaccaria, Daniele; Passarella, Giuseppe; D'Agostino, Daniela; Giordano, Raffaele; Sandoval-Solis, Samuel; Maggi, Sabino; Bruno, Delia; Foglia, Laura

2017-04-01

A research study was conducted on a coastal irrigated agricultural area of southern Italy to assess the risks of aquifer degradation likely resulting from the intensive groundwater pumping from individual farm wells and reduced aquifer recharge. Information were collected both from farmers and delivery system's operators during a survey conducted in 2012 revealing that farmers depend mainly on groundwater with the aim to achieve flexible irrigation management as opposed to the rigid rotational delivery service of surface water supply provided by the local water management agency. The study area is intensively farmed by small land-holding growers with high-value micro-irrigated horticultural crops. Our team appraised the soil and aquifer degradation hazards using a simplified procedure for environmental risk assessment that allowed identifying the risk-generating processes, evaluating the magnitude of impacts, and estimating the overall risks significance. We also collected the stakeholders' perceptions on agricultural water management and use through field interviews, whereas parallel investigations revealed significant aquifer salinity increase during the recent years. As a final step, some preliminary risk mitigation options were appraised by exploring the growers' response to possible changes of irrigation deliveries by the water management agency. The present study integrated multi-annual observations, data interpretation, and modelling efforts, which jointly enabled the analysis of complex water management scenarios and the development of informed decisions. Keywords: Environmental risk assessment, Fuzzy cognitive maps, Groundwater degradation, Seawater intrusion

A combined physicochemical-biological method of NaCl extraction from the irrigation solution in the BTLSS

NASA Astrophysics Data System (ADS)

Trifonov, Sergey V.; Tikhomirov, Alexander A.; Ushakova, Sofya; Tikhomirova, Natalia

2016-07-01

The use of processed human wastes as a source of minerals for plants in closed biotechnical life support systems (BTLSS) leads to high salt levels in the irrigation solution, as urine contains high concentrations of NaCl. It is important to develop a process that would effectively decrease NaCl concentration in the irrigation solution and return this salt to the crew's diet. The salt-tolerant plants (Salicornia europea) used to reduce NaCl concentration in the irrigation solution require higher salt concentrations than those of the solution, and this problem cannot be resolved by concentrating the solution. At the same time, NaCl extracted from mineralized wastes by physicochemical methods is not pure enough to be included in the crew's diet. This study describes an original physicochemical method of NaCl extraction from the solution, which is intended to be used in combination with the biological method of NaCl extraction by using saltwort plants. The physicochemical method produces solutions with high NaCl concentrations, and saltwort plants serve as a biological filter in the final phase, to produce table salt. The study reports the order in which physicochemical and biological methods of NaCl extraction from the irrigation solution should be used to enable rapid and effective inclusion of NaCl into the cycling of the BTLSS with humans. This study was carried out in the IBP SB RAS and supported by the grant of the Russian Science Foundation (Project No. 14-14-00599).

A quantitative and qualitative analysis of ultrasonic versus sonic endodontic systems on canal cleanliness and obturation.

PubMed

Kanter, Valerie; Weldon, Emily; Nair, Uma; Varella, Claudio; Kanter, Keith; Anusavice, Kenneth; Pileggi, Roberta

2011-12-01

The purpose of this study was to compare 2 irrigation techniques by evaluating canal cleanliness and obturation of lateral/accessory canals. Seventy-five extracted canines were instrumented to a size #40/0.06 taper. The EndoActivator (EA) was compared with an ultrasonic unit for final irrigation. Each unit was used for 1 minute each with 6.15% NaOCl and 17% EDTA. A control group received syringe irrigation. Thirty teeth were sectioned and evaluated for debris removal and open dentinal tubules at 3/5 mm from the apical foramen with a scanning electron microscope. Forty-five teeth were examined for obturation of lateral canals. The EA was significantly better in removing debris at all levels when compared with other treatment groups (P < .05) and resulted in obturation of significantly more numbers of lateral canals (P < .01.) The EA provided better obturation of lateral and accessory canals and resulted in less remaining debris. Copyright © 2011 Mosby, Inc. All rights reserved.

Seasonal variation of carbon dioxide fluxes over irrigated soybean ( Glycine max L.)

NASA Astrophysics Data System (ADS)

Şaylan, Levent; Kimura, Reiji; Munkhtsetseg, Erdenebayar; Kamichika, Makio

2011-08-01

In this study, variations in carbon dioxide (CO2) fluxes resulting from gross primary production (GPP), net ecosystem exchange (NEE), and respiration ( R e) of soybean ( Glycine max L.) were investigated by the Eddy Covariance method during the growing period from June to November 2005 on an irrigated sand field at the Arid Land Research Center, Tottori University in Tottori, Japan. Although climatic conditions were humid and temperate, the soybeans required frequent irrigation because of the low water holding capacity of the sandy soil at the field site. Finally, it has been found that the accumulated NEE, GPP, and R e fluxes of soybean over 126 days amount to -93, 319, and 226 gC m-2, respectively. Furthermore, the average ratio of GPP to R e was 1.4 and the average ratio of NEE to GPP was about -0.29 for the growth period of soybean. Daily maximum NEE of -3.8 gC m-2 occurred when LAI was 1.1.

Sodium Hypochlorite Irrigation and Its Effect on Bond Strength to Dentin

PubMed Central

Abuhaimed, Tariq S.

2017-01-01

Effective shaping and cleaning of root canals are essential for the success of endodontic treatment. Due to the complex anatomy of root canal spaces, the use of various instrumentation techniques alone is not effective in producing bacteria-free root canal spaces. Irrigation, disinfectants, rinses, and intervisit medications are used in conjunction with the mechanical instrumentation to ensure the success of endodontic treatment. Sodium hypochlorite (NaOCl), a halogenated compound, is routinely used to irrigate the root canal during endodontic treatments. NaOCl has been known for its antibacterial action, proteolytic and dissolution capacity, and debridement properties. NaOCl, however, can alter the composition of dentin and hence its interaction with the adhesive resins used to bond the restorative materials to treated dentin. This review therefore covers in depth the action of NaOCl on dentin-adhesive resin bond strength including both enhancement and reduction, then mechanisms proposed for such action, and finally how the adverse action of NaOCl on dentin can be reversed. PMID:28904947

Sodium Hypochlorite Irrigation and Its Effect on Bond Strength to Dentin.

PubMed

Abuhaimed, Tariq S; Abou Neel, Ensanya A

2017-01-01

Effective shaping and cleaning of root canals are essential for the success of endodontic treatment. Due to the complex anatomy of root canal spaces, the use of various instrumentation techniques alone is not effective in producing bacteria-free root canal spaces. Irrigation, disinfectants, rinses, and intervisit medications are used in conjunction with the mechanical instrumentation to ensure the success of endodontic treatment. Sodium hypochlorite (NaOCl), a halogenated compound, is routinely used to irrigate the root canal during endodontic treatments. NaOCl has been known for its antibacterial action, proteolytic and dissolution capacity, and debridement properties. NaOCl, however, can alter the composition of dentin and hence its interaction with the adhesive resins used to bond the restorative materials to treated dentin. This review therefore covers in depth the action of NaOCl on dentin-adhesive resin bond strength including both enhancement and reduction, then mechanisms proposed for such action, and finally how the adverse action of NaOCl on dentin can be reversed.

Evaluation of the influence of time and concentration of sodium hypochlorite on the bond strength of glass fibre post.

PubMed

Knight, Beau; Love, Robert M; George, Roy

2017-10-24

This study evaluated the effect of time and concentrations of sodium hypochlorite on the bond strength of a glass fibre post cemented in a root canal with resin cement. A total of 45 single-rooted extracted human teeth were prepared with Protaper ® universal files, randomly allocated into nine groups and then subjected to 1% or 4% NaOCl for a period of 1 min or 2 min. Fibre posts were then bonded into the root canal, sectioned and the bond strength tested using a push-out test. A longer irrigation time resulted in a significant reduction (P < 0.05) in bond strength, while a final additional irrigation with distilled water significantly reduced bond strength. The concentration of NaOCl did not significantly affect bond strength. Within the limitations of this study, it was observed that regardless of the concentration of NaOCl used, shorter irrigation times favoured better fibre post bonding. © 2017 Australian Society of Endodontology Inc.

A risk assessment framework for irrigated agriculture under climate change

NASA Astrophysics Data System (ADS)

Ronco, P.; Zennaro, F.; Torresan, S.; Critto, A.; Santini, M.; Trabucco, A.; Zollo, A. L.; Galluccio, G.; Marcomini, A.

2017-12-01

In several regions, but especially in semi-arid areas, raising frequency, duration and intensity of drought events, mainly driven by climate change dynamics, are expected to dramatically reduce the current stocks of freshwater resources, limiting crop development and yield especially where agriculture largely depends on irrigation. The achievement of an affordable and sustainable equilibrium between available water resources and irrigation demand is essentially related to the planning and implementation of evidence-based adaptation strategies and actions. The present study proposed a state-of-the art conceptual framework and computational methodology to assess the potential water scarcity risk, due to changes in climate trends and variability, on irrigated croplands. The model has been tested over the irrigated agriculture of Puglia Region, a semi-arid territory with the largest agricultural production in Southern Italy. The methodology, based on the Regional Risk Assessment (RRA) approach, has been applied within a scenario-based hazard framework. Regional climate projections, under alternative greenhouse gas concentration scenarios (RCP4.5 and RCP8.5) and for two different timeframes, 2021-2050 and 2041-2070 compared to the baseline 1976-2005 period, have been used to drive hydrological simulations of river inflow to the most important reservoirs serving irrigation purposes in Puglia. The novelty of the proposed RRA-based approach does not simply rely on the concept of risk as combination of hazard, exposure and vulnerability, but rather elaborates detailed (scientific and conceptual) framing and computational description of these factors, to produce risk spatial pattern maps and related statistics distinguishing the most critical areas (risk hot spots).. The application supported the identification of the most affected areas (i.e. Capitanata Reclamation Consortia under RCP8.5 2041-2070 scenario), crops (fruit trees and vineyards), and, finally, the vulnerability pattern of irrigation systems and networks. The implemented assessment singled out future perspectives of water scarcity risk levels for irrigated agriculture by the administrative extent where individual bodies are in charge of the coordination of public and private irrigation activities (i.e. Reclamation Consortia). Based on the outcomes of the proposed methodology, tailored and knowledge-based adaptation strategies and related actions can be developed, to reduce the risk at both agronomic level (i.e. preferring crops with low vulnerability score, as olive groves) and at structural level (i.e. differentiating the water stocks and supplies and reducing losses and inefficiencies).

Extended use of grey water for irrigating home gardens in an arid environment.

PubMed

Al-Ismaili, Abdulrahim M; Ahmed, Mushtaque; Al-Busaidi, Ahmed; Al-Adawi, Seif; Tandlich, Roman; Al-Amri, Mohammed

2017-05-01

The use of treated grey water (GW) for home gardens, peri-urban agriculture and landscaping is becoming popular in many water stressed countries such as Oman. This study aims to investigate the treatment efficacy, health and chemical concerns, cost-benefits and maintenance protocol of a GW treatment system as well as the effect of irrigation with GW on crop yield. Therefore, a decentralized homemade GW treatment system was installed in a newly constructed house in Muscat, Oman and studied over a 2-year period. The treated GW was found to be suitable for irrigation as per Omani standards. GW when mixed with kitchen effluent substituted the use of nutrient supplements for plants and did not show any harmful chemical or biological contamination. The capital cost of the system was around US $980, and the annual operating cost was US $78 with annual income and savings from the system being around US $572 indicating a payback period of nearly 2 years. It was found that the system required simple but regular maintenance particularly cleaning of the top layer of the filter. It can be concluded from this study that such a GW system should be technically, economically and environmentally feasible in Oman. Also, wider acceptance by the general public to the idea of GW reuse will help in mitigating the water shortage problem of the country to some extent.

Does periprocedural anticoagulation management of atrial fibrillation affect the prevalence of silent thromboembolic lesion detected by diffusion cerebral magnetic resonance imaging in patients undergoing radiofrequency atrial fibrillation ablation with open irrigated catheters? Results from a prospective multicenter study.

PubMed

Di Biase, Luigi; Gaita, Fiorenzo; Toso, Elisabetta; Santangeli, Pasquale; Mohanty, Prasant; Rutledge, Neal; Yan, Xue; Mohanty, Sanghamitra; Trivedi, Chintan; Bai, Rong; Price, Justin; Horton, Rodney; Gallinghouse, G Joseph; Beheiry, Salwa; Zagrodzky, Jason; Canby, Robert; Leclercq, Jean François; Halimi, Franck; Scaglione, Marco; Cesarani, Federico; Faletti, Riccardo; Sanchez, Javier; Burkhardt, J David; Natale, Andrea

2014-05-01

Silent cerebral ischemia (SCI) has been reported in 14% of cases after catheter ablation of atrial fibrillation (AF) with radiofrequency (RF) energy and discontinuation of warfarin before AF ablation procedures. The purpose of this study was to determine whether periprocedural anticoagulation management affects the incidence of SCI after RF ablation using an open irrigated catheter. Consecutive patients undergoing RF ablation for AF without warfarin discontinuation and receiving heparin bolus before transseptal catheterization (group I, n = 146) were compared with a group of patients who had protocol deviation in terms of maintaining the therapeutic preprocedural international normalized ratio (patients with subtherapeutic INR) and/or failure to receive pretransseptal heparin bolus infusion and/or ≥2 consecutive ACT measurements <300 seconds (noncompliant population, group II, n = 134) and with a group of patients undergoing RF ablation with warfarin discontinuation bridged with low molecular weight heparin (group III, n = 148). All patients underwent preablation and postablation (within 48 hours) diffusion magnetic resonance imaging. SCI was detected in 2% of patients (3/146) in group I, 7% (10/134) in group II, and 14% (21/148) in group III (P <.001). "Therapeutic INR" was strongly associated with a lower prevalence of postprocedural silent cerebral ischemia (SCI). Multivariable analysis demonstrated nonparoxysmal AF (odds ratio 3.8, 95% confidence interval 1.5-9.7, P = .005) and noncompliance to protocol (odds ratio 2.8, 95% confidence interval 1.5-5.1, P <.001] to be significant predictors of ischemic events. Strict adherence to an anticoagulation protocol significantly reduces the prevalence of SCI after catheter ablation of AF with RF energy. Copyright © 2014 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

In-situ Use of Ground Water by Alfalfa

USDA-ARS?s Scientific Manuscript database

One proposal for drainage water disposal is to reuse drainage water for irrigation of salt tolerant crops until the volume has been reduced sufficiently to enable final disposal by evaporation. Part of this concept of serial biological concentration requires in-situ crop water reuse from shallow gr...

Production cost analysis of Euphorbia lathyris. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mendel, D.A.

1979-08-01

The purpose of this study is to estimate costs of production for Euphorbia lathyris (hereafter referred to as Euphorbia) in commercial-scale quantities. Selection of five US locations for analysis was based on assumed climatic and cultivation requirements. The five areas are: nonirrigated areas (Southeast Kansas and Central Oklahoma, Northeast Louisiana and Central Mississippi, Southern Illinois), and irrigated areas: (San Joaquin Valley and the Imperial Valley, California and Yuma, Arizona). Cost estimates are tailored to reflect each region's requirements and capabilities. Variable costs for inputs such as cultivation, planting, fertilization, pesticide application, and harvesting include material costs, equipment ownership, operating costs,more » and labor. Fixed costs include land, management, and transportation of the plant material to a conversion facility. Euphorbia crop production costs, on the average, range between $215 per acre in nonirrigated areas to $500 per acre in irrigated areas. Extraction costs for conversion of Euphorbia plant material to oil are estimated at $33.76 per barrel of oil, assuming a plant capacity of 3000 dry ST/D. Estimated Euphorbia crop production costs are competitive with those of corn. Alfalfa production costs per acre are less than those of Euphorbia in the Kansas/Oklahoma and Southern Illinois site, but greater in the irrigated regions. This disparity is accounted for largely by differences in productivity and irrigation requirements.« less

The impacts of climate change on irrigation and crop production in Northeast China and implications for energy use and GHG Emission

NASA Astrophysics Data System (ADS)

Yan, Tingting; Wang, Jinxia; Huang, Jikun; Xie, Wei; Zhu, Tingju

2018-06-01

The water-food-energy-GHG nexus under climate change has been gaining increasing attention from both the research and policy communities, especially over the past several years. However, most existing nexus studies are qualitative and explorative in nature. So far, very few studies provide integrated analysis of this nexus across all the four sectors. The purpose of this paper is to examine this nexus by assessing the effects of climate change on agricultural production through the change in water availability, evaluating the adjustment responses and resulting energy consumption and GHG emission, with the Northeast China as a case study. Based on our simulation results, by 2030, climate change is projected to increase water supply and demand gap for irrigation in Northeast China. Due to the increase in water scarcity, irrigated areas will decrease, and the cropping pattern will be adjusted by increasing maize sown areas and decreasing rice sown areas. As a result, the total output of crops and profits will clearly be reduced. Finally, energy consumption and GHG emission from irrigation will be reduced. This study suggests that climate change impact assessment fully consider the nexus among water, food, energy and GHG; however, more studies need to be conducted in the future.

Effectiveness of different final irrigation techniques and placement of endodontic sealer into dentinal tubules.

PubMed

Oliveira, Kauhanna Vianna de; Silva, Bruno Marques da; Leonardi, Denise Piotto; Crozeta, Bruno Monguilhott; Sousa-Neto, Manoel Damião de; Baratto-Filho, Flares; Gabardo, Marilisa Carneiro Leão

2017-12-18

The aim of this study was to compare two irrigation techniques and four devices for endodontic sealer placement into the dentinal tubules. Ninety-nine single-rooted human teeth were instrumented and allocated to either the control (CO) (n=11) or experimental groups according to the irrigation method: syringe and NaveTip needle (NT) (n=44), and EndoActivator (EA) (n=44). These groups were subdivided according to sealer placement into K-File (KF), lentulo spiral (LS), Easy Clean (EC), and EndoActivator (EA) subgroups. Moreover, the distances of 5 mm and 2 mm from the apex were analyzed. The teeth were obturated with AH Plus and GuttaCore X3. Analyses were performed by scanning electron microscopy associated to cathodoluminescence. The percentage and maximum depth of sealer penetration were measured. Data were evaluated by three-way analysis of variance (ANOVA) and Games-Howell test (p<0.05). EA was superior to NT in percentage of sealer penetration. EC was significantly superior to EA (subgroup) for sealer penetration, and both improved the percentage of sealer penetration when compared to LS. Better sealer penetration was observed at the distance of 5 mm from the apex. Sealer penetration into the dentinal tubules was significantly improved by sonic irrigant activation.

Exploring the relationship between irrigation water requirements and potential yield in the Huang-Huai-Hai plain

NASA Astrophysics Data System (ADS)

Tang, Huaxiu; Zhan, Jinyan; Deng, Xiangzheng; Ma, Jinsong

2007-11-01

By using the GIS technologies, we interpolate the site-based meteorological data into climatic surface data, which are the main input parameters for the CropWat model, used to estimate the reference evapotranspiration (ET 0). And then by combining the ET 0 with the information on share of cultivated land decoded from the Landsat TM/ETM digital imagines covering the entire case study area, the Huang-Huai-Hai plain, we estimate the amount of irrigation water requirements (IWRs) in the years of 1991 and 2000. We then introduce the potential yield (PY) of cultivated land estimated from the Estimation Model for the Agricultural Productivity Potential (EMAPP) to explore the relationship between the IWRs and the PY . By conducting GIS-based spatial overlay analyses, we explore the positive correlation relationship between the IWRs and the PY of cultivated land. Finally, we conclude that the IWRs is now a constrain factor on the PY of cultivated land in the Huang-Huai-Hai plain in those areas with the irrigation water constrains. The result has offered a scientific basis for the decision makings in the exploitation and utilization of resources and energy as well as the land use planning, protection of the potential yields and the managements of irrigation water at the regional level.

A generic open-source toolbox to help long term irrigation monitoring for integrated water management in semi-arid Mediterranean areas.

NASA Astrophysics Data System (ADS)

Le Page, Michel; Gosset, Cindy; Oueslati, Ines; Calvez, Roger; Zribi, Mehrez; Lili Chabaane, Zohra

2016-04-01

In semi arid areas, irrigated plains are often the major consumer of water well beyond other water demands. Traditionally fed by surface water, irrigation has massively shifted to a more reliable resource: groundwater. This shift occurred in the late thirty years has also provoked an extension and intensification of irrigation, often translated into impressive groundwater table decreases. Integrated water management needs a systematic and robust way to estimate the water demands by the agricultural sector. We propose a generic toolbox based on the FAO-56 method and the Crop Coefficient/NDVI approach used in Remote Sensing. The toolbox can be separated in three main areas: 1) It facilitates the preparation of different input datasets: download, domain extraction, homogenization of formats, or spatial interpolation. 2) A collection of algorithms based on the analysis of NDVI time series is proposed: Separation of irrigated vs non-irrigated area, a simplified annual land cover classification, Crop Coefficient, Fraction Cover and Efficient Rainfall. 3) Synthesis against points or areas produces the output data at the desired spatial and temporal resolution for Integrated Water Modeling or data analysis and comparison. The toolbox has been used in order to build a WEAP21 model of the Merguellil basin in Tunisia for the period of 2000-2014. Different meteorological forcings were easily used and compared: WFDEI, AGRI4CAST, MED-CORDEX. A local rain gauges database was used to produce a daily rainfall gridded dataset. MODIS MOD13Q1 (16 days, 250m) data was used to produce the NDVI derived datasets (Kc, Fc, RainEff). Punctual evapotranspiration was compared to actual measurements obtained by flux towers on wheat and barley showing good agreements on a daily basis (r2=0.77). Finally, the comparison to monthly statistics of three irrigated commands was performed over 4 years. This late comparison showed a bad agreement which led us to suppose two things: First, the simple approach of (Evapotranspiration minus Efficient Rainfall) to estimate Irrigation at the monthly time step is not pertinent because only a subset of the irrigated commands is actually irrigated. Hence, a higher spatial resolution of remote sensing imagery is needed. Second, in this particular area, farmers have a different rationale about rainfall and irrigation water needs. Those two aspects need to be further investigated. The toolbox has proven to be an interesting tool to integrate different sources of data, efficiently process them and easily produce input data for the WEAP1 model on a long term range. Yet some new challenges have been raised.

Erbium:Yttrium Aluminum Garnet Laser-Activated Sodium Hypochlorite Irrigation: A Promising Procedure for Minimally Invasive Endodontics.

PubMed

Cheng, Xiaogang; Tian, Tiantian; Tian, Yu; Xiang, Doudou; Qiu, Jun; Liu, Xiaohua; Yu, Qing

2017-12-01

This study was to evaluate the potential of Erbium:Yttrium Aluminum Garnet laser-activated sodium hypochlorite irrigation (Er:YAG + NaOCl) for minimally invasive endodontics (MIE). Er:YAG laser irradiation can dramatically enhance the penetration of NaOCl, which may be a promising protocol for MIE. Extracted human teeth were contaminated with Enterococcus faecalis for 4 weeks. The infected canals were then shaped to different apical terminal working widths (ATWW, 15#/0.04, 20#/0.04, 25#/0.04, 30#/0.04, and 40#/0.04) and treated with either Er:YAG + NaOCl (0.3 W, 20 sec) or NaOCl alone. Then, the ATWW were fixed at 15#/0.04, and the canals were treated with Er:YAG + NaOCl at 0.3 W for 40 and 60 sec, or at 0.5 and 1.0 W for 20 sec. Finally, bacterial reductions were evaluated using the cell count method. Er:YAG + NaOCl showed a higher disinfection efficacy at each ATWW compared with NaOCl alone (p < 0.001). The maximum bacterial reduction was 99.9% for the 40#/Er:YAG + NaOCl group and 93.6% for the 40#/NaOCl group. To achieve similar disinfection efficacy, the Er:YAG + NaOCl group needed a smaller ATWW than the NaOCl group. At a fixed ATWW, increasing the output power of the Er:YAG laser was more effective than increasing the radiation time to improve the disinfection efficacy of Er:YAG + NaOCl. The 15#/Er:YAG + NaOCl group reached the maximum bacterial reduction of 99.2% when the Er:YAG laser was activated at 1.0 W for 20 sec. The 15#/Er:YAG + NaOCl with the Er:YAG laser irradiation at 1.0 W for 20 sec may be considered a promising procedure for MIE.

Response to deep hypoglycemia does not involve glucoreceptors in carotid perfused tissue

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cane, P.; Haun, C.K.; Evered, J.

1988-11-01

In the present study the authors examined whether the magnified hormonal counter-regulatory response seen during deep hypoglycemia (40 mg/dl) could be attenuated by supplying the forebrain with glucose furnished through carotid infusion. Two protocols were performed in conscious dogs. In the first protocol they infused glucose bilaterally into the carotid circulation to produce a forebrain glycemia of 55 {plus minus} 1 mg/dl whereas systemic glycemia declined to 39 {plus minus} 2 mg/dl. In the second protocol as a control they infused glucose into the systemic circulation at a rate matched to protocol 1 so that both systemic and jugular plasmamore » glucose concentrations were equivalent to the systemic glucose concentrations in protocol 1. In spite of a substantial difference in forebrain glycemia there were no differences in the counter-regulatory responses of catecholamines or glucagon. In addition, through the use of radiolabeled microspheres, they defined the precise regions of the forebrain irrigated during bilateral intracarotid glucose infusions. The concentration of microspheres was high in the forebrain but very low in the hindbrain. The results indicate that glucoreceptor cells in tissues perfused by carotid arteries may play a tautological role in the sympathetic response to hypoglycemia and imply that glucose-sensitive receptors must also be located elsewhere in the central nervous system or in the periphery.« less

Water saving at the field scale with Irrig-OH, an open-hardware environment device for soil water potential monitoring and irrigation management

NASA Astrophysics Data System (ADS)

Masseroni, Daniele; Facchi, Arianna; Gandolfi, Claudio

2015-04-01

Sustainability of irrigation practices is an important objective which should be pursued in many countries, especially in areas where water scarcity causes strong conflicts among the different water uses. The efficient use of water is a key factor in coping with the food demand of an increasing world population and with the negative effects of the climate change on water resources availability in many areas. In this complex context, it is important that farmers adopt instruments and practices that enable a better management of water at the field scale, whatever the irrigation method they adopt. This work presents the hardware structure and the functioning of an open-hardware microstation based on the Arduino technology, called Irrig-OH, which allows the continuous and low-cost monitoring of the soil water potential (SWP) in the root zone for supporting the irrigation scheduling at the field scale. In order to test the microstation, an experiment was carried out during the agricultural season 2014 at Lodi (Italy), with the purpose of comparing the farmers' traditional management of irrigation of a peach variety and the scheduling based on the SWP measurements provided by the microstation. Additional measurements of leaf water potential (LWP), stomatal resistance, transpiration (T), crop water stress index (CWSI) and fruit size evolution were performed respectively on leafs and fruits for verifying the plant physiological responses on different SWP levels in soil. At the harvesting time, the peach production in term of quantity and quality (sucrose content was measured by a rifractometer over a sample of one hundred fruits) of the two rows were compared. Irrigation criteria was changed with respect to three macro-periods: up to the endocarp hardening phase (begin of May) soil was kept well watered fixing the SWP threshold in the first 35 cm of the soil profile at -20 kPa, during the pit hardening period (about the entire month of May) the allowed SWP threshold was -30 kPa and, finally, from the end of May to the harvesting time (maturation process), irrigation was applied when SWP reached -25 kPa. Every time irrigation events were stopped when SWP at the field capacity (-10 kPa) was restored in the upper part of the root zone. Results showed a water saving of nearly 50% using the Irrig-OH device, without consequences on the quantity and quality of the production. Plant physiological status based on LWP, T and CWSI measurements showed that despite the different irrigation treatments adopted, no considerable plant stress was found in both rows. In particular, maximum values of the previous indices, performed at midday, were respectively -2 MPa, 1.4 mm h-1 and 0.6, which were in good agreement with those observed by many researches for no-stressed peach orchards in Mediterranean areas.

7 CFR 718.103 - Prevented planted and failed acreage.

Code of Federal Regulations, 2014 CFR

2014-01-01

... prevented-planted acreage was affected by drought, unless: (1) On the final planting date for non-irrigated.... Drought Monitor; and (3) Verifiable information is collected from sources whose business or purpose it is... a lack of water resulting from drought conditions or contamination by saltwater intrusion of an...

7 CFR 760.815 - Calculation of prevented planted acreage.

Code of Federal Regulations, 2011 CFR

2011-01-01

... acreage was affected by a disaster that was caused by drought unless on the final planting date or the... from being planted due to a lack of water resulting from drought conditions or contamination by saltwater intrusion of an irrigation supply resulting from drought conditions. (h) For NAP covered crops...

7 CFR 760.815 - Calculation of prevented planted acreage.

Code of Federal Regulations, 2012 CFR

2012-01-01

... acreage was affected by a disaster that was caused by drought unless on the final planting date or the... from being planted due to a lack of water resulting from drought conditions or contamination by saltwater intrusion of an irrigation supply resulting from drought conditions. (h) For NAP covered crops...

7 CFR 718.103 - Prevented planted and failed acreage.

Code of Federal Regulations, 2010 CFR

2010-01-01

... prevented-planted acreage was affected by drought, unless: (1) On the final planting date for non-irrigated.... Drought Monitor; and (3) Verifiable information is collected from sources whose business or purpose it is... a lack of water resulting from drought conditions or contamination by saltwater intrusion of an...

7 CFR 718.103 - Prevented planted and failed acreage.

Code of Federal Regulations, 2013 CFR

2013-01-01

... prevented-planted acreage was affected by drought, unless: (1) On the final planting date for non-irrigated.... Drought Monitor; and (3) Verifiable information is collected from sources whose business or purpose it is... a lack of water resulting from drought conditions or contamination by saltwater intrusion of an...

7 CFR 760.815 - Calculation of prevented planted acreage.

Code of Federal Regulations, 2014 CFR

2014-01-01

... acreage was affected by a disaster that was caused by drought unless on the final planting date or the... from being planted due to a lack of water resulting from drought conditions or contamination by saltwater intrusion of an irrigation supply resulting from drought conditions. (h) For NAP covered crops...

7 CFR 760.815 - Calculation of prevented planted acreage.

Code of Federal Regulations, 2013 CFR

2013-01-01

... acreage was affected by a disaster that was caused by drought unless on the final planting date or the... from being planted due to a lack of water resulting from drought conditions or contamination by saltwater intrusion of an irrigation supply resulting from drought conditions. (h) For NAP covered crops...

7 CFR 718.103 - Prevented planted and failed acreage.

Code of Federal Regulations, 2012 CFR

2012-01-01

... prevented-planted acreage was affected by drought, unless: (1) On the final planting date for non-irrigated.... Drought Monitor; and (3) Verifiable information is collected from sources whose business or purpose it is... a lack of water resulting from drought conditions or contamination by saltwater intrusion of an...

7 CFR 760.815 - Calculation of prevented planted acreage.

Code of Federal Regulations, 2010 CFR

2010-01-01

... acreage was affected by a disaster that was caused by drought unless on the final planting date or the... from being planted due to a lack of water resulting from drought conditions or contamination by saltwater intrusion of an irrigation supply resulting from drought conditions. (h) For NAP covered crops...

7 CFR 718.103 - Prevented planted and failed acreage.

Code of Federal Regulations, 2011 CFR

2011-01-01

... prevented-planted acreage was affected by drought, unless: (1) On the final planting date for non-irrigated.... Drought Monitor; and (3) Verifiable information is collected from sources whose business or purpose it is... a lack of water resulting from drought conditions or contamination by saltwater intrusion of an...

SUSTAINABLE BUILDING DESIGN FOR A SCHOOL – COMMUNITY CENTER IN RURAL NIGERIA

EPA Science Inventory

We expect to find adequate information that will aid in designing a rainwater collection, protection, and irrigation system appropriate for the future school construction. The final design of the school building will develop in a manner that will allow villagers to maintain an...

43 CFR 2521.5 - Annual proof.

Code of Federal Regulations, 2011 CFR

2011-10-01

... the land, in permanent improvements thereon, and in the purchase of water rights for the irrigation... extent of the improvements placed on the claim. Said act, however, authorizes the submission of final...., and for the first breaking or clearing of the soil are also acceptable. (2) The value to be attached...

Disinfecting Effects of Rotary Instrumentation with Either 2.5% Sodium Hypochlorite or 2% Chlorhexidine as the Main Irrigant: A Randomized Clinical Study.

PubMed

Rôças, Isabela N; Provenzano, José Claudio; Neves, Mônica A S; Siqueira, José F

2016-06-01

This randomized clinical study compared the antibacterial effects of irrigation with either 2.5% sodium hypochlorite (NaOCl) or 2% chlorhexidine (CHX) during the preparation of infected root canals with rotary nickel-titanium instruments. The root canals of 50 single-rooted teeth with apical periodontitis were prepared by using BioRaCe rotary instruments (FKG Dentaire, La Chaux-de-Fonds, Switzerland) and irrigation with either 2.5% NaOCl (n = 25) or 2% CHX (n = 25). Samples were taken from the canal at baseline (S1) and after (S2) chemomechanical preparation. DNA was extracted from the clinical samples, and the reduction of the levels of total bacteria and streptococci was evaluated by means of a 16S ribosomal RNA gene-based quantitative polymerase chain reaction assay. All S1 samples were positive for the presence of bacteria. After chemomechanical preparation using either 2.5% NaOCl or 2% CHX, 44% and 40% of the root canals still had detectable bacteria, respectively. As for total bacterial counts, a mean number of 3.7 × 10(5) bacterial cell equivalents was present in S1 samples from the NaOCl group, with a substantial reduction in S2 to a mean of 5.49 × 10(2) cell equivalents (P < .001). In the CHX group, a mean bacterial load of 8.77 × 10(4) cell equivalents occurred in S1, with a significant reduction in S2 to a mean of 2.81 × 10(3) cells (P < .001). The differences in both the presence/absence and quantitative data were not statistically significant (P > .05). Both irrigation protocols were highly effective in reducing the levels of Streptococcus species (P < .001). No significant difference was observed for the clinical antibacterial effectiveness of rotary preparation using either 2.5% NaOCl or 2% CHX as the main irrigant. Copyright © 2016. Published by Elsevier Inc.

Comparative Evaluation of Smear Layer and Debris on the Canal Walls prepared with a Combination of Hand and Rotary ProTaper Technique using Scanning Electron Microscope.

PubMed

Kiran, S; Prakash, Sandeep; Siddharth, Pujari R; Saha, Supradip; Geojan, Naiza E; Ramachandran, Mookambika

2016-07-01

The effect of smear layer and debris on the success rate of endodontic treatment has not yet been definitely determined. So the present study was aimed to evaluate the amount of smear layer and debris on the canal walls prepared with a combination of hand and rotary ProTaper technique using NaOCl and ethylenediaminetetraacetic acid (EDTA) alternately as root canal irrigants using scanning electron microscope (SEM). Eighty intact freshly extracted human permanent mandibular premolar teeth were collected and randomly divided equally into four groups. In group I canals were prepared with hand K-Flexofiles; group II with rotary ProTaper instruments; group III with rotary ProTaper instruments and final instrumentation was done with hand K-Flexofile; group IV with rotary ProTaper instruments and final instrumentation was done with RC-Prep and irrigated with 1 mL of normal saline. In all groups canals were irrigated using NaOCl and EDTA alternately. After instrumentation, the teeth were prepared for SEM examination using five-score indices for debris and smear layer at coronal, middle, and apical third levels. Statistical analysis was performed using chi-square test (p < 0.05) and Kruskal-Wallis test (p < 0.05). Statistically significant difference was observed between the groups in cleaning the apical third. Groups I and III showed better canal cleanliness compared to group II. The use of EDTA and NaOCl in group III was more effective in removing debris and smear layer compared to EDTA and normal saline in group IV. Regardless of the instrumentation technique employed and the irrigant used, the cleaning ability decreased in the apical third, resulting in higher debris and smear layer scores compared to coronal and middle third levels. None of the instrumentation techniques in the present study could completely eliminate the smear layer and debris from the canal walls. Instrumentation of the canals with hand files after automated rotary preparation could result in cleaner canal walls. Alternate irrigation with NaOCl and EDTA is effective in the removal of debris and smear layer in the coronal and middle level, but the effectiveness in the apical third is less.

Modeling large-scale human alteration of land surface hydrology and climate

NASA Astrophysics Data System (ADS)

Pokhrel, Yadu N.; Felfelani, Farshid; Shin, Sanghoon; Yamada, Tomohito J.; Satoh, Yusuke

2017-12-01

Rapidly expanding human activities have profoundly affected various biophysical and biogeochemical processes of the Earth system over a broad range of scales, and freshwater systems are now amongst the most extensively altered ecosystems. In this study, we examine the human-induced changes in land surface water and energy balances and the associated climate impacts using a coupled hydrological-climate model framework which also simulates the impacts of human activities on the water cycle. We present three sets of analyses using the results from two model versions—one with and the other without considering human activities; both versions are run in offline and coupled mode resulting in a series of four experiments in total. First, we examine climate and human-induced changes in regional water balance focusing on the widely debated issue of the desiccation of the Aral Sea in central Asia. Then, we discuss the changes in surface temperature as a result of changes in land surface energy balance due to irrigation over global and regional scales. Finally, we examine the global and regional climate impacts of increased atmospheric water vapor content due to irrigation. Results indicate that the direct anthropogenic alteration of river flow in the Aral Sea basin resulted in the loss of 510 km3 of water during the latter half of the twentieth century which explains about half of the total loss of water from the sea. Results of irrigation-induced changes in surface energy balance suggest a significant surface cooling of up to 3.3 K over 1° grids in highly irrigated areas but a negligible change in land surface temperature when averaged over sufficiently large global regions. Results from the coupled model indicate a substantial change in 2 m air temperature and outgoing longwave radiation due to irrigation, highlighting the non-local (regional and global) implications of irrigation. These results provide important insights on the direct human alteration of land surface water and energy balances, highlighting the need to incorporate human activities such as irrigation into the framework of global climate models and Earth system models for better prediction of future changes under increasing human influence and continuing global climate change.

"More drop per crop" when moving from gravitational to drip irrigated agriculture? Experiences from a North Moroccan case study

NASA Astrophysics Data System (ADS)

Feltz, N.; Gaspart, F.; Vanclooster, M.

2015-12-01

In order to save agricultural water, the famous FAO's "more crop per drop" has been taken literally in many arid or semi-arid places around the world and policies that aim improving "efficiencies" (irrigation efficiency…) have been implemented, often leading to the promotion of water saving technologies. In 1865, studying coal consumption, W.S. Jevons highlighted that improving coal use efficiency could, as a paradox, lead to higher global coal use. Many economists later extended this idea to resource saving technologies in general, showing that, due to the "rebound effect", the adoption of more efficient technologies, in terms of use of resources, could lead to a higher global consumption of this resource if this adoption didn't go with adjustment measures. Regarding these considerations, the emerging question is to which extent water saving technologies (i.e. that aim improving water related efficiencies) are appropriate to save water at large scale. Our study addresses this question through the analysis of the conversion from surface to drip irrigation in Triffa's irrigated perimeter (Morocco). We aim addressing this question using the detailed analysis of two data sets. First, available data were collected for every farm within the study area from the local administrations. Second, interviews were conducted with farmers to complete the dataset and to characterize their behavior. This allowed assessing water related efficiencies at farm scale. Subsequently, models were implemented to link efficiencies with general attributes and thereby identify the main drivers of water related efficiencies in the study area. Finally, these models were used to upscale farm-scale assessment to the perimeter scale. Our results show that, under current conditions, moving from surface to drip irrigation leads to higher global water withdrawal. However, the aforementioned "rebound effect" does not allow explaining the higher pressure because of contextual specificities. Deeper analysis suggests that economic but also social and psychological issues need to be considered in this transition process. To fully achieve the expected results from moving to drip irrigation, those issues must be dealt with and the transition to drip irrigation must go hand in hand with stewardship programs and appropriate farmers capacity building.

43 CFR 2521.6 - Final proof.

Code of Federal Regulations, 2011 CFR

2011-10-01

... marked increase in the growth of grass or that grass sufficient to support stock has been produced on the..., no crops except grass can be successfully produced, or if actual tillage will destroy or injure the... before stated, that same was produced as a result of actual irrigation. (h) Showing as to water right. (1...

Effectiveness of repeated photodynamic therapy in the elimination of intracanal Enterococcus faecalis biofilm: an in vitro study.

PubMed

Prażmo, Ewa Joanna; Godlewska, Renata Alicja; Mielczarek, Agnieszka Beata

2017-04-01

The study aimed to investigate the effectiveness of photodynamic therapy in the elimination of intracanal Enterococcus faecalis biofilm and to analyse how a repeated light irradiation, replenishment of oxygen and photosensitiser affect the results of the photodynamic disinfecting protocol. After chemomechanical preparation, 46 single-rooted human teeth were infected with a clinical strain of E. faecalis and incubated for a week in microaerobic conditions. The experimental procedures included groups of single application of photodynamic therapy, two cycles of PDT, irrigation with 5.25% NaOCl solution and negative and positive control. The number of residing bacterial colonies in the root canals was determined based on the CFU/ml method. In the group of preparations irrigated with NaOCl, bacterial colonies were not observed. A single PDT eliminated 45% of the initial CFU/ml. Repeated PDT eradicated 95% of the intracanal bacterial biofilm. Photodynamic therapy has a high potential for the elimination of E. faecalis biofilm. There is a safe therapeutic window where photoinduced disinfection can be used as an adjuvant to conventional endodontic treatment, which remains the most effective.

Estimation of Soil Radon Concentration in Al-Qateef's Date Palm Farms, Saudi Arabia

DOE Office of Scientific and Technical Information (OSTI.GOV)

Al-Ghamdi, S. S.; Al-Garawi, M. S.; Baig, M. R.

2011-10-27

This study involves the measurement of radon concentrations in agricultural soil from two date Palm farms in Al-Qateef province using CR-39 detector. In each farm the palm trees are arranged in rows separated by the irrigation reservoirs. The first farm is about 10000 m{sup 2} and has 350 palm trees and the second farm is about 7000 m{sup 2} and has 320 palm trees. The average distance between trees is about 5.5 m. The rows are separated by an irrigation reservoir where fertilizers are added. Sixty soil samples were collected from each farm and classified in paperboard boxes. These samplesmore » were taken from different depths and positions between the trees and from the irrigation reservoir.A newly designed tag type dosimeter is used in which the alpha tracks are registered on both sides of the CR-39 detector. The tag dosimeter was calibrated against a cup type dosimeter which was calibrated at the National Radiological Protection Board (NRPB) at the U.K.The detectors were left to count for five months and then chemically treated in the standard way. Finally an optical microscope is used to count alpha tracks and the data are treated statistically.The study is set to test for significant differences in radon concentrations at different positions and depths in the barren and fertilized soils in the two farms. Measured radon concentrations ranged between 42 and 344Bq/m{sup 3}. No significant difference between the mean concentration values in soil samples taken between the trees and that taken at the depth of 50 cm from the irrigation reservoir. Significant difference was however found between radon concentrations in samples collected directly from the surface of the irrigation reservoir where fertilizers are introduced and those taken from the other two positions. The used fertilizers are found to have higher contents of uranium which is limited to the surface soil of the irrigation reservoir.« less

Estimation of Soil Radon Concentration in Al-Qateef's Date Palm Farms, Saudi Arabia

NASA Astrophysics Data System (ADS)

Al-Ghamdi, S. S.; Al-Garawi, M. S.; Baig, M. R.; Al-Sameen, M.

2011-10-01

This study involves the measurement of radon concentrations in agricultural soil from two date Palm farms in Al-Qateef province using CR-39 detector. In each farm the palm trees are arranged in rows separated by the irrigation reservoirs. The first farm is about 10000 m2 and has 350 palm trees and the second farm is about 7000 m2 and has 320 palm trees. The average distance between trees is about 5.5 m. The rows are separated by an irrigation reservoir where fertilizers are added. Sixty soil samples were collected from each farm and classified in paperboard boxes. These samples were taken from different depths and positions between the trees and from the irrigation reservoir. A newly designed tag type dosimeter is used in which the alpha tracks are registered on both sides of the CR-39 detector. The tag dosimeter was calibrated against a cup type dosimeter which was calibrated at the National Radiological Protection Board (NRPB) at the U.K. The detectors were left to count for five months and then chemically treated in the standard way. Finally an optical microscope is used to count alpha tracks and the data are treated statistically. The study is set to test for significant differences in radon concentrations at different positions and depths in the barren and fertilized soils in the two farms. Measured radon concentrations ranged between 42 and 344Bq/m3. No significant difference between the mean concentration values in soil samples taken between the trees and that taken at the depth of 50 cm from the irrigation reservoir. Significant difference was however found between radon concentrations in samples collected directly from the surface of the irrigation reservoir where fertilizers are introduced and those taken from the other two positions. The used fertilizers are found to have higher contents of uranium which is limited to the surface soil of the irrigation reservoir.

Effect of irrigated rice agriculture on Japanese encephalitis, including challenges and opportunities for integrated vector management.

PubMed

Keiser, Jennifer; Maltese, Michael F; Erlanger, Tobias E; Bos, Robert; Tanner, Marcel; Singer, Burton H; Utzinger, Jürg

2005-07-01

Japanese encephalitis (JE) is a disease caused by an arbovirus that is spread by marsh birds, amplified by pigs, and mainly transmitted by the bite of infected Culex tritaeniorhynchus mosquitoes. The estimated annual incidence and mortality rates are 30,000--50,000 and 10,000, respectively, and the estimated global burden of JE in 2002 was 709,000 disability-adjusted life years lost. Here, we discuss the contextual determinants of JE, and systematically examine studies assessing the relationship between irrigated rice agriculture and clinical parameters of JE. Estimates of the sizes of the rural population and population in irrigated areas are presented, and trends of the rural population, the rice-irrigated area, and the rice production are analyzed from 1963 to 2003. We find that approximately 1.9 billion people currently live in rural JE-prone areas of the world. Among them 220 million people live in proximity to rice-irrigation schemes. In 2003, the total rice harvested area of all JE-endemic countries (excluding the Russian Federation and Australia) was 1,345,000 km(2). This is an increase of 22% over the past 40 years. Meanwhile, the total rice production in these countries has risen from 226 millions of tonnes to 529 millions of tonnes (+134%). Finally, we evaluate the effect of different vector control interventions in rice fields, including environmental measures (i.e. alternate wet and dry irrigation (AWDI)), and biological control approaches (i.e. bacteria, nematodes, invertebrate predators, larvivorous fish, fungi and other natural products). We conclude that in JE-endemic rural settings, where vaccination rates are often low, an integrated vector management approach with AWDI and the use of larvivorous fish as its main components can reduce vector populations, and hence has the potential to reduce the transmission level and the burden of JE.

Using Remote Sensing to Determine Timing of High Altitude Grass Hay Growth Stages

NASA Astrophysics Data System (ADS)

Mefford, B.

2015-12-01

Remote sensing has become the standard for collecting data to determine potential irrigation consumptive use in Wyoming for the Green River Basin. The Green River Basin within Wyoming is around 10.8 million acres, located in south western Wyoming and is a sub-basin of the Colorado River Basin. Grass hay is the main crop grown in the basin. The majority of the hay is grown at elevations 7,000 feet above mean sea level. Daily potential irrigation consumptive use is calculated for the basin during the growing season (May 1st to September 30th). To determine potential irrigation consumptive use crop coefficients, reference evapotranspiration (ET) and effective precipitation are required. Currently crop coefficients are the hardest to determine as most research on crop coefficients are based at lower elevations. Values for crop coefficients for grass hay still apply to high altitude grass hay, but the hay grows at a much slower rate than low elevation grass hay. To be able to more accurately determine the timing of the growth stages of hay in this basin, time-lapse cameras were installed at two different irrigated hay fields in the basin for the 2015 growing season and took pictures automatically once a day at 1 P.M.. Both of the fields also contained a permanent research grade weather station. Imagery obtained from these cameras was used as indicators of timing of the major growth stages of the hay and the length of days between the stages. A crop coefficient value was applied every day in the growing season based on the results from the imagery. Daily potential ET was calculated using the crop coefficients and the data from the on-site weather stations. The final result was potential irrigation induced crop consumptive use for each site. Using remote sensing provided necessary information that normally would be applied arbitrarily in determining irrigation induced consumptive use in the Green River Basin.

Soil Types Effect on Grape and Wine Composition in Helan Mountain Area of Ningxia

PubMed Central

Wang, Rui; Sun, Quan; Chang, Qingrui

2015-01-01

Different soil types can significantly affect the composition of wine grapes and the final wine product. In this study, the effects of soil types on the composition of Cabernet Sauvignon grapes and wine produced in the Helan Mountains were evaluated. Three different representative soil types—aeolian, sierozem and irrigation silting soil were studied. The compositions of grapes and wines were measured, and in addition, the weights of 100-berry samples were determined. The grapes that grown on the aeolian and sierozem soils matured sooner than those grown on the irrigation silting soil. The highest sugar content, total soluble solids content, sugar to acid ratio and anthocyanin content were found in the grapes that grown on the aeolian soil. The wine produced from this soil had improved chroma and tone and higher-quality phenols. The grapes grown on the sierozem soil had the highest total phenol and tannin contents, which affected the wine composition. The grapes grown on the irrigation silting soil had higher acidities, but the remaining indices were lower. In addition, the grapes grown on the aeolian soil resulted in wines with better chroma and aroma. The sierozem soil was beneficial for the formation of wine tannins and phenols and significantly affected the wine composition. The quality of the grapes from the irrigation silting soil was relatively low, resulting in lower-quality wine. PMID:25706126

Efficacy of new irrigating solution on smear layer removal in apical third of root canal: A scanning electron microscope study.

PubMed

Patil, Priyanka Himmatrao; Gulve, Meenal Nitin; Kolhe, Swapnil Janardan; Samuel, Roshan Mathew; Aher, Gayatri Balasaheb

2018-01-01

The aim of this in vitro study is to evaluate and compare the smear layer removal efficacy of etidronic acid-based irrigating solution with others in the apical third of the root canal. Forty human single-rooted mandibular premolar teeth were taken and decoronated to standardize the canal length. After biomechanical preparation, teeth were randomly divided into four groups ( n = 10) and the final irrigation was carried out with tested irrigants. Group I: normal saline (negative control); Group II: 5.25% sodium hypochlorite (NaOCl) with surfactant and 17% ethylenediaminetetraacetic acid (EDTA) with surfactant; Group III: freshly mixed BioPure MTAD; and Group IV: freshly mixed Chloroquick solution. The teeth were split into two halves and observed under a scanning electron microscope to analyze the amount of smear layer present. Data were analyzed using the Kruskal-Wallis test and Mann-Whitney test. Group II (5.25% NaOCl with surfactant followed by 17% EDTA with surfactant) showed least smear layer scores (1.1 ± 0.3162). This was followed by Group III (MTAD) (2.2 ± 0.4216) and then Group IV (Chloroquick) (2.4 ± 0.5164). Sequential use of 5.25% NaOCl with surfactant and 17% EDTA with surfactant was found to be the most efficient than MTAD and Chloroquick in the removal of smear layer in the apical third of root canal.

Effectiveness of Three Different Irrigants - 17% Ethylenediaminetetraacetic Acid, Q-MIX, and Phytic Acid in Smear Layer Removal: A Comparative Scanning Electron Microscope Study.

PubMed

Jagzap, Janhavi Balasaheb; Patil, Sanjay S; Gade, Vandana Jaykumar; Chandhok, Deepika J; Upagade, Madhura A; Thakur, Deepa A

2017-01-01

Removal of smear layer from the root canal walls is important for long-standing endodontic success. The aim of this study is to evaluate and compare smear layer removing ability among 17% ethylenediaminetetraacetic acid (EDTA), Q-MIX, and phytic acid by scanning electron microscopy (SEM). This in-vitro experimental study assessed smear layer removal using three different irrigants. Thirty single-rooted freshly extracted human permanent premolars were collected, disinfected, and decoronated to a standardized root length of 13 mm. Root canals were cleaned and shaped till F2 universal rotary protaper at working length 1 mm short of the apex. They were randomly divided into three groups, and final irrigation was done accordingly. Group 1 ( n = 10): with 1 ml of 17% EDTA, Group 2 ( n = 10): with 1 ml of Q-MIX, Group 3 ( n = 10): with 1 ml of phytic acid. Samples were then longitudinally sectioned and evaluated under SEM at coronal, middle, and apical levels. Two-way analysis of variance and Tukey's post hoc test were performed. The level of significance was set at 0.05. Smear layer removing ability among irrigants and sections in descending order: 17 EDTA > Q-MIX > phytic acid; coronal > middle > apical. 17% EDTA showed better and promising results followed by Q-MIX and then phytic acid.

Active biomonitoring with the moss Pseudoscleropodium purum: Comparison between different types of transplants and bulk deposition.

PubMed

Ares, A; Varela, Z; Aboal, J R; Carballeira, A; Fernández, J A

2015-10-01

Active biomonitoring with terrestrial mosses can be used to complement traditional air pollution monitoring techniques. Several studies have been carried out to compare the uptake capacity of different types of moss transplants. However, until now the relationship between the uptake of elements in devitalized moss bags and in irrigated transplants has not been explored. In this study, the final concentrations of Cd, Cu, Hg, Pb and Zn were determined in irrigated and devitalized moss transplants in the surroundings of a steelworks. The concentrations were also compared with those of the same elements in the bulk deposition to determine which type of moss transplant yields the closest correlations. Devitalized moss retained higher concentrations of all of the elements (except Hg) than the irrigated moss. Both irrigated and devitalized moss transplants appear to detect the same type of contamination (i.e. particulate matter and dissolved metals rather than gaseous forms) as significant correlations were found for Cu, Hg, Pb and Zn, whereas, neither type of the moss transplant was sensitive enough to detect changes in the soluble fraction load of bulk deposition. Further studies will be needed to a better understanding of the correlation between the concentrations of elements in moss transplants with the particulate fraction of the bulk deposition. This will enable the establishment of a more robust and accurate biomonitoring tool. Copyright © 2015 Elsevier Inc. All rights reserved.

Soil types effect on grape and wine composition in Helan Mountain area of Ningxia.

PubMed

Wang, Rui; Sun, Quan; Chang, Qingrui

2015-01-01

Different soil types can significantly affect the composition of wine grapes and the final wine product. In this study, the effects of soil types on the composition of Cabernet Sauvignon grapes and wine produced in the Helan Mountains were evaluated. Three different representative soil types--aeolian, sierozem and irrigation silting soil were studied. The compositions of grapes and wines were measured, and in addition, the weights of 100-berry samples were determined. The grapes that grown on the aeolian and sierozem soils matured sooner than those grown on the irrigation silting soil. The highest sugar content, total soluble solids content, sugar to acid ratio and anthocyanin content were found in the grapes that grown on the aeolian soil. The wine produced from this soil had improved chroma and tone and higher-quality phenols. The grapes grown on the sierozem soil had the highest total phenol and tannin contents, which affected the wine composition. The grapes grown on the irrigation silting soil had higher acidities, but the remaining indices were lower. In addition, the grapes grown on the aeolian soil resulted in wines with better chroma and aroma. The sierozem soil was beneficial for the formation of wine tannins and phenols and significantly affected the wine composition. The quality of the grapes from the irrigation silting soil was relatively low, resulting in lower-quality wine.

Geochemical processes controlling water salinization in an irrigated basin in Spain: identification of natural and anthropogenic influence.

PubMed

Merchán, D; Auqué, L F; Acero, P; Gimeno, M J; Causapé, J

2015-01-01

Salinization of water bodies represents a significant risk in water systems. The salinization of waters in a small irrigated hydrological basin is studied herein through an integrated hydrogeochemical study including multivariate statistical analyses and geochemical modeling. The study zone has two well differentiated geologic materials: (i) Quaternary sediments of low salinity and high permeability and (ii) Tertiary sediments of high salinity and very low permeability. In this work, soil samples were collected and leaching experiments conducted on them in the laboratory. In addition, water samples were collected from precipitation, irrigation, groundwater, spring and surface waters. The waters show an increase in salinity from precipitation and irrigation water to ground- and, finally, surface water. The enrichment in salinity is related to the dissolution of soluble mineral present mainly in the Tertiary materials. Cation exchange, precipitation of calcite and, probably, incongruent dissolution of dolomite, have been inferred from the hydrochemical data set. Multivariate statistical analysis provided information about the structure of the data, differentiating the group of surface waters from the groundwaters and the salinization from the nitrate pollution processes. The available information was included in geochemical models in which hypothesis of consistency and thermodynamic feasibility were checked. The assessment of the collected information pointed to a natural control on salinization processes in the Lerma Basin with minimal influence of anthropogenic factors. Copyright © 2014 Elsevier B.V. All rights reserved.

A New Weak Chelator in Endodontics: Effects of Different Irrigation Regimens with Etidronate on Root Dentin Microhardness

PubMed Central

Tartari, Talita; de Almeida Rodrigues Silva e Souza, Patrícia; Vila Nova de Almeida, Bruno; Carrera Silva Júnior, José Otávio; Facíola Pessoa, Oscar; Silva e Souza Junior, Mario Honorato

2013-01-01

This study investigated the effect of sodium hypochlorite (NaOCl), ethylenediaminetetraacetic (EDTA), etidronic (HEBP), and citric acid (CA) associated in different irrigation regimens on root dentin microhardness. Forty-five root halves of single-rooted teeth were sectioned into thirds that were embedded in acrylic resin, polished, randomly assigned into 3 groups, and treated as follows: G1: saline solution; G2: 5% NaOCl + 18% HEBP, mixed in equal parts; and G3: 2.5% NaOCl. After measurements, the G3 samples were distributed into subgroups G4, G5, and G6, which were submitted to 17% EDTA, 10% CA and 9% HEBP, respectively. Following the new measurements, these groups received a final flush with 2.5% NaOCl, producing G7, G8, and G9. Microhardness was measured with Knoop indenter under a 25 g load for 15 seconds, before and after treatments. The data were statistically analyzed using paired Student's t-test (α<0.05) to compare values before and after treatments and analysis of variance (ANOVA) (α<0.05) to detect any differences among thirds. Except G1, all tested irrigation regimens significantly decreased the microhardness. There were no differences between root thirds before treatments, and all root thirds exhibited equal responses to same treatment. Except saline, all tested irrigation regimens reduced the root dentin microhardness. PMID:23983692

76 FR 50164 - Protocol Gas Verification Program and Minimum Competency Requirements for Air Emission Testing...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-12

...-AQ06 Protocol Gas Verification Program and Minimum Competency Requirements for Air Emission Testing... correct certain portions of the Protocol Gas Verification Program and Minimum Competency Requirements for... final rule that amends the Agency's Protocol Gas Verification Program (PGVP) and the minimum competency...

A cost-effective and customizable automated irrigation system for precise high-throughput phenotyping in drought stress studies

PubMed Central

2018-01-01

The development of high-yielding crops with drought tolerance is necessary to increase food, feed, fiber and fuel production. Methods that create similar environmental conditions for a large number of genotypes are essential to investigate plant responses to drought in gene discovery studies. Modern facilities that control water availability for each plant remain cost-prohibited to some sections of the research community. We present an alternative cost-effective automated irrigation system scalable for a high-throughput and controlled dry-down treatment of plants. This system was tested in sorghum using two experiments. First, four genotypes were subjected to ten days of dry-down to achieve three final Volumetric Water Content (VWC) levels: drought (0.10 and 0.20 m3 m-3) and control (0.30 m3 m-3). The final average VWC was 0.11, 0.22, and 0.31 m3 m-3, respectively, and significant differences in biomass accumulation were observed between control and drought treatments. Second, 42 diverse sorghum genotypes were subjected to a seven-day dry-down treatment for a final drought stress of 0.15 m3 m-3 VWC. The final average VWC was 0.17 m3 m-3, and plants presented significant differences in photosynthetic rate during the drought period. These results demonstrate that cost-effective automation systems can successfully control substrate water content for each plant, to accurately compare their phenotypic responses to drought, and be scaled up for high-throughput phenotyping studies. PMID:29870560

A cost-effective and customizable automated irrigation system for precise high-throughput phenotyping in drought stress studies.

PubMed

Ortiz, Diego; Litvin, Alexander G; Salas Fernandez, Maria G

2018-01-01

The development of high-yielding crops with drought tolerance is necessary to increase food, feed, fiber and fuel production. Methods that create similar environmental conditions for a large number of genotypes are essential to investigate plant responses to drought in gene discovery studies. Modern facilities that control water availability for each plant remain cost-prohibited to some sections of the research community. We present an alternative cost-effective automated irrigation system scalable for a high-throughput and controlled dry-down treatment of plants. This system was tested in sorghum using two experiments. First, four genotypes were subjected to ten days of dry-down to achieve three final Volumetric Water Content (VWC) levels: drought (0.10 and 0.20 m3 m-3) and control (0.30 m3 m-3). The final average VWC was 0.11, 0.22, and 0.31 m3 m-3, respectively, and significant differences in biomass accumulation were observed between control and drought treatments. Second, 42 diverse sorghum genotypes were subjected to a seven-day dry-down treatment for a final drought stress of 0.15 m3 m-3 VWC. The final average VWC was 0.17 m3 m-3, and plants presented significant differences in photosynthetic rate during the drought period. These results demonstrate that cost-effective automation systems can successfully control substrate water content for each plant, to accurately compare their phenotypic responses to drought, and be scaled up for high-throughput phenotyping studies.

Development of deficit irrigation scheduling strategies for 'Prime Giant' sweet cherry

NASA Astrophysics Data System (ADS)

Blanco, Víctor; Domingo, Rafael; Torres, Roque; Pérez Pastor, Alejandro; García, Manuel; López, Juan Antonio

2016-04-01

Precision regulated deficit irrigation scheduling is useful for improving water productivity and ensuring crop production sustainability. This form of water management requires continuous monitoring in order to know soil and/or plant water status at all times. Water status sensors are key tools for modulating irrigation water amounts. The objective of this work was to study the physiological and agronomic response of cherry trees to different irrigation treatments based on crop evapotranspiration (ETc). However, the final purpose was to establish threshold values of water stress indicators, which can be considered of practical applicability in automatic irrigation scheduling. The experiment was carried out in 2015 in a 0.5 ha commercial plot of 'Prime Giant' cherry [Prunus avium (L.)] in SE Spain. Three treatments were studied i) T110, irrigated above the maximum crop water requirements (110% of ETc), ii) T85, sustained deficit irrigation, irrigated to satisfy 85% of ETc, throughout the growing season, and iii) T100-55, regulated deficit irrigation with different water deficit levels: 100% and 55% of ETc during pre- and postharvest, respectively. Each treatment was randomly distributed in blocks and run in triplicate. Soil and plant water status were assessed from the soil matric potential and volumetric water content (Ym and Ov), midday stem and fruit water potential (Ys and Yf), maximum daily trunk shrinkage (MDS), daily trunk growth rate (TGR), stomatal conductance (gs), photosynthesis (Pn) and transpiration rates (E). Vegetative growth, yield and the quality of the fruit were also evaluated. Ys and MDS signal intensity were used as the main indicators of water stress. The water applied during the 2015 growing season was 7190, 5425 and 4225 m3 ha-1 for T110, T85 and T100-55, respectively. The mean values of Ys during pre- and postharvest were -0.51, -0.57, -0.54 and -0.65, -0.77 and -0.97 MPa in T110, T85 and T100-55, respectively, while Yf was -1.20, -1.36, -1.27 MPa, during the preharvest period, respectively. The deficit irrigation strategies tested, T85 and T100-55, corresponded to equivalent signal intensities of Ys, 1.1 and 1.05, and of MDS 1.40 and 1.25, respectively, which would denote that the treatment irrigated to satisfy 100% of ETc during preharvest (T100-55) was slightly stressed. Our results show that the water regime applied generated statistically significance differences between treatments both in plant (Ys, Yf, MDS, TGR, gs, Pn, E) and soil (Ym, Ov) water relations. There were no differences in vegetative growth, trunk cross-sectional area or summer pruning values. The irrigation strategies followed did not cause any difference in total production (16.1 t ha-1). Moreover, fruit quality at harvest did not differ between treatments, except for the solid soluble content and unitary cherry weight, when significant differences were obtained. The results confirm the usefulness of support deficit irrigation scheduling in sweet cherry trees. However, these good results need to be followed up in subsequent growing seasons. This study was funded by the Spanish Ministry for Economy and Competitiveness (MINECO) and the European Agricultural Funds for Rural Development. Reference: AGL2013-49047-C2-1-R.

Comparison of ozone gas and sodium hypochlorite/chlorhexidine two-visit disinfection protocols in treating apical periodontitis: a randomized controlled clinical trial.

PubMed

Kist, Stefan; Kollmuss, Maximilian; Jung, Jette; Schubert, Sören; Hickel, Reinhard; Huth, Karin Christine

2017-05-01

In this single-blinded, prospective, randomized, controlled clinical trial, the effectiveness of an ozone gas or NaOCl/CHX disinfection protocol was compared within the root canal treatment of apical periodontitis. Sixty permanent teeth were randomly allocated to one technique. The clinical/radiographic assessment criteria included clinical symptoms, periapical index (PAI), and size of the apical lesion. In both groups, the root canal was mechanically cleaned and irrigated with NaCl and EDTA. Ozone gas (32 g m -3 ) or NaOCl (3 %) was applied followed by a 1-week inter-appointment dressing (Ca(OH) 2 ). As final disinfection, ozone gas (ozone group) or CHX 2 % (NaOCl group) was applied. Microbial samples were taken after preparing the access cavity, after chemo-mechanical treatment and after inter-appointment dressing by sterile paper points. Microbial identification was performed by mass spectroscopy (MALDI-TOF-MS) and 16S-rRNA gene sequencing. The treated teeth were blindly re-evaluated after 6/12 months. Success rates, the decrease in PAI, the size of apical lesions and bacterial reduction were compared between groups (Fischer's exact test, Mann-Whitney U test). There were no significant differences between the success rates (ozone group: 96.2/95.5 % after 6/12 months; NaOCl group: 95.5/95.2 % after 6/12 months). The differences in the decreases in PAI values and apical lesion sizes were also insignificant after 6 and 12 months. The bacterial reduction showed no significant differences between groups after chemo-mechanical treatment and after inter-appointment dressing. The most commonly found bacterial genera were Streptococcus spp., Parvimonas spp. and Prevotella spp. The here used ozone gas and NaOCl/CHX protocols showed no difference in bacterial reduction in the sampled areas of the root canals. Within the limitations of the study, ozone gas seems to be a possible alternative disinfection agent within the root canal treatment of apical periodontitis.

RESPONSE PROTOCOL TOOLBOX: PLANNING FOR AND RESPONDING TO DRINKING WATER CONTAMINATION THREATS AND INCIDENTS. OVERVIEW AND APPLICATION. INTERIM FINAL - DECEMBER 2003

EPA Science Inventory

The interim final Response Protocol Toolbox: Planning for and Responding to Contamination Threats to Drinking Water Systems is designed to help the water sector effectively and appropriately respond to intentional contamination threats and incidents. It was produced by EPA, buil...

RESPONSE PROTOCOL TOOLBOX: PLANNING FOR AND RESPONDING TO DRINKING WATER CONTAMINATION THREATS AND INCIDENTS. MODULE 4: ANALYTICAL GUIDE. INTERIM FINAL - DECEMBER 2003

EPA Science Inventory

The interim final Response Protocol Toolbox: Planning for and Responding to Contamination Threats to Drinking Water Systems is designed to help the water sector effectively and appropriately respond to intentional contamination threats and incidents. It was produced by EPA, buil...

Protocols for Copying and Proofreading in Template-Assisted Polymerization

NASA Astrophysics Data System (ADS)

Pigolotti, Simone; Sartori, Pablo

2016-03-01

We discuss how information encoded in a template polymer can be stochastically copied into a copy polymer. We consider four different stochastic copy protocols of increasing complexity, inspired by building blocks of the mRNA translation pathway. In the first protocol, monomer incorporation occurs in a single stochastic transition. We then move to a more elaborate protocol in which an intermediate step can be used for error correction. Finally, we discuss the operating regimes of two kinetic proofreading protocols: one in which proofreading acts from the final copying step, and one in which it acts from an intermediate step. We review known results for these models and, in some cases, extend them to analyze all possible combinations of energetic and kinetic discrimination. We show that, in each of these protocols, only a limited number of these combinations leads to an improvement of the overall copying accuracy.

Effect of EDTA conditioning upon the retention of fibre posts luted with resin cements.

PubMed

Rasimick, B J; Shah, R P; Musikant, B L; Deutsch, A S

2008-12-01

To determine if a final rinse with EDTA improves the short-term in-tooth retentive strength of adhesively luted fibre-reinforced composite posts. Six different commercial fibre post systems were tested. Post spaces in extracted human anterior teeth were irrigated with either 6% NaOCl or 6% NaOCl followed by 17% EDTA. Posts were luted using the manufacturer's recommended bonding agent and luting cement. Two different sizes of post were tested for each post system. After 24 h of storage, the retentive strength of the post to the tooth (14 per group, 336 total) was tested using a pull-out technique. Three-way anova and the Student-Newman-Kuels test were used to test the effects of irrigation regimen, post size and post brand on the retentive strength of the fibre post. Almost every sample failed at the interface between dentine and luting cement. Irrigation method did not have any significant effect (P > 0.14) for any group other than ParaPost Fibre White (P < 0.001). The overall retention of a post appeared to be correlated to the amount of surface texture on the post; the smooth ICEPost was the least retentive brand, the textured FibreKor and the ParaPost Fibre White posts were moderately retained, and the threaded Flexi-Post Fibre and the Flexi-Flange Fibre posts were the most retentive brands tested. For all brands, larger diameter posts were more retentive than smaller diameter posts (P < 0.008). A final rinse of EDTA did not improve the short-term retention of fibre posts except for ParaPost Fibre White.

The self-adjusting file (SAF). Part 3: removal of debris and smear layer-A scanning electron microscope study.

PubMed

Metzger, Zvi; Teperovich, Ehud; Cohen, Raphaela; Zary, Raviv; Paqué, Frank; Hülsmann, Michael

2010-04-01

The aim of this study was to evaluate the cleaning ability of the Self-Adjusting File (SAF) system in terms of removal of debris and smear layer. Root canal preparations were performed in 20 root canals using an SAF operated with a continuous irrigation device. The glide path was initially established using a size 20 K-file followed by the SAF file that was operated in the root canal via a vibrating motion for a total of 4 minutes. Sodium hypochlorite (3%) and EDTA (17%) were used as continuous irrigants and were alternated every minute during this initial 4-minute period. This was followed by a 30-second rinse using EDTA applied through a nonactivated SAF and a final flush with sodium hypochlorite. The roots were split longitudinally and subjected to scanning electron microscopy (SEM). The presence of debris and a smear layer in the coronal, middle, and apical thirds of the canal were evaluated through the analysis of the SEM images using five-score evaluation systems based on reference photographs. The SAF operation with continuous irrigation, using alternating irrigants, resulted in root canal walls that were free of debris in all thirds of the canal in all (100%) of the samples. In addition, smear layer-free surfaces were observed in 100% and 80% of the coronal and middle thirds of the canal, respectively. In the apical third of the canal, smear layer-free surfaces were found in 65% of the root canals. The operation of the SAF system with continuous irrigation coupled with alternating sodium hypochlorite and EDTA treatment resulted in a clean and mostly smear layer-free dentinal surface in all parts of the root canal. Copyright (c) 2010 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Investigation of the Efficacy of Passive Ultrasonic Irrigation Versus Irrigation with Reciprocating Activation: An Environmental Scanning Electron Microscopic Study.

PubMed

Kato, Augusto Shoji; Cunha, Rodrigo Sanches; da Silveira Bueno, Carlos Eduardo; Pelegrine, Rina Andrea; Fontana, Carlos Eduardo; de Martin, Alexandre Sigrist

2016-04-01

The objective of this ex vivo study was to compare the efficacy of passive ultrasonic irrigation (PUI) versus a new activation system using reciprocating motion (EasyClean [EC]; Easy Equipamentos Odontológicos, Belo Horizonte, Brazil) to remove debris from the root canal walls at 6 predetermined apical levels using environmental scanning electron microscopy. Mesiobuccal root canals of 10 mandibular molars were prepared with a 30/.05 final instrument. The specimens were embedded in flasks containing heavy body silicone, cleaved longitudinally, and 6 round indentations were made into the apical region of the buccal half at 1-mm intervals. The same specimens were used to prepare a blank control group (no debris), a negative control group (completely covered by debris), and 2 experimental groups: PUI and irrigation with reciprocating activation. Standardized images of the indentations were obtained under environmental scanning electron microscopy and assessed by 2 examiners. The amount of debris was then classified using a 4-category scoring system. The kappa test was applied to determine interexaminer agreement, whereas the Kruskal-Wallis, Dunn, and Friedman tests were used to compare scores. The EC group had results statistically similar to those of the blank control group for all 6 root levels examined. The PUI group had results statistically similar to those of the negative control group for the 3 most apical levels and similar to those of the blank control group for the 3 most cervical levels. Activating the irrigant with a reciprocating system (EC) promoted more effective debris removal from the more apical regions of the root canal when compared with PUI. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Significant impacts of irrigation water sources and methods on modeling irrigation effects in the ACME Land Model

DOE PAGES

Leng, Guoyong; Leung, L. Ruby; Huang, Maoyi

2017-06-20

An irrigation module that considers both irrigation water sources and irrigation methods has been incorporated into the ACME Land Model (ALM). Global numerical experiments were conducted to evaluate the impacts of irrigation water sources and irrigation methods on the simulated irrigation effects. All simulations shared the same irrigation soil moisture target constrained by a global census dataset of irrigation amounts. Irrigation has large impacts on terrestrial water balances especially in regions with extensive irrigation. Such effects depend on the irrigation water sources: surface-water-fed irrigation leads to decreases in runoff and water table depth, while groundwater-fed irrigation increases water table depth,more » with positive or negative effects on runoff depending on the pumping intensity. Irrigation effects also depend significantly on the irrigation methods. Flood irrigation applies water in large volumes within short durations, resulting in much larger impacts on runoff and water table depth than drip and sprinkler irrigations. Differentiating the irrigation water sources and methods is important not only for representing the distinct pathways of how irrigation influences the terrestrial water balances, but also for estimating irrigation water use efficiency. Specifically, groundwater pumping has lower irrigation water use efficiency due to enhanced recharge rates. Different irrigation methods also affect water use efficiency, with drip irrigation the most efficient followed by sprinkler and flood irrigation. Furthermore, our results highlight the importance of explicitly accounting for irrigation sources and irrigation methods, which are the least understood and constrained aspects in modeling irrigation water demand, water scarcity and irrigation effects in Earth System Models.« less

Significant impacts of irrigation water sources and methods on modeling irrigation effects in the ACME Land Model

DOE Office of Scientific and Technical Information (OSTI.GOV)

Leng, Guoyong; Leung, L. Ruby; Huang, Maoyi

An irrigation module that considers both irrigation water sources and irrigation methods has been incorporated into the ACME Land Model (ALM). Global numerical experiments were conducted to evaluate the impacts of irrigation water sources and irrigation methods on the simulated irrigation effects. All simulations shared the same irrigation soil moisture target constrained by a global census dataset of irrigation amounts. Irrigation has large impacts on terrestrial water balances especially in regions with extensive irrigation. Such effects depend on the irrigation water sources: surface-water-fed irrigation leads to decreases in runoff and water table depth, while groundwater-fed irrigation increases water table depth,more » with positive or negative effects on runoff depending on the pumping intensity. Irrigation effects also depend significantly on the irrigation methods. Flood irrigation applies water in large volumes within short durations, resulting in much larger impacts on runoff and water table depth than drip and sprinkler irrigations. Differentiating the irrigation water sources and methods is important not only for representing the distinct pathways of how irrigation influences the terrestrial water balances, but also for estimating irrigation water use efficiency. Specifically, groundwater pumping has lower irrigation water use efficiency due to enhanced recharge rates. Different irrigation methods also affect water use efficiency, with drip irrigation the most efficient followed by sprinkler and flood irrigation. Furthermore, our results highlight the importance of explicitly accounting for irrigation sources and irrigation methods, which are the least understood and constrained aspects in modeling irrigation water demand, water scarcity and irrigation effects in Earth System Models.« less

Fertigation - Injecting soluble fertilizers into the irrigation system: Part 2

Treesearch

Thomas D. Landis; Jeremy R. Pinto; Anthony S. Davis

2010-01-01

The first part of this article in the Summer 2009 issue covered basic mineral nutrition, the 3 components of a fertigation system, and the chemical calculations forformulating your own custom fertigation solutions. In this second and final part, we'll discuss types of fertilizer injectors, fertigation scheduling, and how to check injector function and determine...

RESPONSE PROTOCOL TOOLBOX: PLANNING FOR AND RESPONDING TO DRINKING WATER CONTAMINATION THREATS AND INCIDENTS. MODULE 1: WATER UTILITIES PLANNING GUIDE - INTERIM FINAL - DECEMBER 2003

EPA Science Inventory

The interim final Response Protocol Toolbox: Planning for and Responding to Contamination Threats to Drinking Water Systems is designed to help the water sector effectively and appropriately respond to intentional contamination threats and incidents. It was produced by EPA, buil...

RESPONSE PROTOCOL TOOLBOX: PLANNING FOR AND RESPONDING TO DRINKING WATER CONTAMINATION THREATS AND INCIDENTS, MODULE 3: SITE CHARACTERIZATION AND SAMPLING GUIDE. INTERIM FINAL - DECEMBER 2003

EPA Science Inventory

The interim final Response Protocol Toolbox: Planning for and Responding to Contamination Threats to Drinking Water Systems is designed to help the water sector effectively and appropriately respond to intentional contamination threats and incidents. It was produced by EPA, buil...

COLT: seasonal prediction of crop irrigation needs

NASA Astrophysics Data System (ADS)

Villani, Giulia; Spisni, Andrea; Mariani, Maria Cristina; Pratizzoli, William; Pavan, Valentina; Tomei, Fausto; Botarelli, Lucio; Marletto, Vittorio

2013-04-01

COLT is an operational chain to predict summer (June, July, August) crop irrigation needs in Emilia-Romagna (Northern Italy) at the regional and lower scales. Set up by ARPA-SIMC in 2010, it has been applied since with good results. COLT predicts summer irrigation needs in May, i.e. at the beginning of the irrigation season in Emilia-Romagna. COLT is based on the production of yearly updated land use maps, observed daily weather data, a regional soil map and ensemble probabilistic seasonal weather forecasts obtained from the EUROSIP multi-model operational system and a geographical soil water balance model (CRITERIA). The first step of the operational scheme is the supervised classification of crops through field surveys and a set of multitemporal satellite images acquired during the first months of the growing period. As the identification of all crop species during the satellite working windows is not feasible, they are grouped in six classes: summer field crops (including corn, sorghum, tomato, sugar beet, potato and others), winter crops (wheat, barley, oat, etc.), perennial grasses (alfa-alfa and meadows), rice, vineyards and orchards, on the whole regional plain, covering about 775000 ha. The second step involves the statistical downscaling of the EUROSIP ensemble predictions over Emilia-Romagna and the use of a weather generator to synthetically produce a number (usually 50) replicated meteorological summer daily data series, consistent with the predicted and downscaled summer anomalies of temperature, rainfall and other related indices. During the final step the CRITERIA model computes crop development and soil water balance on the crop classification map using observed meteorological daily data up to the end of May. Afterword forecasts are used up to the end of the summer irrigation season, i.e. August 31st. The statistical distribution projections of summer irrigation needs at the regional and reclamation consortia scale are then issued and disseminated from the ARPA-SIMC web site. Since 2010 forecasts of the crops water irrigation requirements have been computed and compared with the simulated data at the end of the summer with good results. The COLT scheme is able to predict the very large interannual variability of the seasonal crop water needs: in 2010 the summer was rather wet and COLT predicted about 500 Mm3, while in 2011 the median forecast was 850 Mm3, a value considered as normal. The summer of 2012 was exceptionally dry, thus the median COLT forecast was 1077 Mm3, while the value computed with observed summer data reached 1340 Mm3 (+24%). The COLT scheme was also tested in a study area located near Ravenna (570 ha), where actual crop irrigation volumes are measured. The median forecasted irrigation (0.50 Mm3) resulted 14% higher than the observed value for 2011 (0.44 Mm3), mainly due to errors in classification of non irrigated crops as irrigated, and possibly to the water table not being accounted for in the model. COLT looks like a promising approach for assessing, planning and managing water resources in agriculture, and for mitigating the impacts of intense climate anomalies in the agricultural sector.

Hydrology of a groundwater-irrigated rice field in Bangladesh: Seasonal and daily mechanisms of infiltration

NASA Astrophysics Data System (ADS)

Neumann, Rebecca B.; Polizzotto, Matthew L.; Badruzzaman, A. Borhan M.; Ali, M. Ashraf; Zhang, Zhongyuan; Harvey, Charles F.

2009-09-01

Flow through a groundwater-irrigated rice field in Bangladesh was characterized with data collected from a transect of tensiometers and time domain reflectometry sensors, novel tracer tests, infiltration tests, soil core analyses, and calculated water budgets. The combined data captured the dynamic hydrologic behavior of the rice field over an entire growing season, which included many irrigation events. Recharge to the aquifer flowed from the surface of the rice field through preferential flow paths located in the subsoil beneath the plowed surface of the field and in the bunds, the raised boundaries around the perimeter of the field. Water that remained within the soil matrix did not recharge the aquifer. Bund flow was the dominant loss for the field because the bulk hydraulic conductivity of the soil beneath the bunds was greater than that in the plowed and planted region of the rice field. Each year, farmers plow the rice fields, destroying cracks and decreasing the conductivity of the shallow soil, but leave the bunds unplowed because they follow property boundaries. We determined bund flow with a daily water balance and confirmed its importance by comparing irrigation losses among fields of different sizes and geometries and hence different ratios of perimeter to area. The perimeter-to-area ratio predicted the fraction of water lost down the bunds for these and other fields located throughout Southeast Asia. Finally, we determined the economic and environmental benefits of reducing bund flow.

Evaluation of penetration depth of 2% chlorhexidine digluconate into root dentinal tubules using confocal laser scanning microscope.

PubMed

Vadhana, Sekar; Latha, Jothi; Velmurugan, Natanasabapathy

2015-05-01

This study evaluated the penetration depth of 2% chlorhexidine digluconate (CHX) into root dentinal tubules and the influence of passive ultrasonic irrigation (PUI) using a confocal laser scanning microscope (CLSM). Twenty freshly extracted anterior teeth were decoronated and instrumented using Mtwo rotary files up to size 40, 4% taper. The samples were randomly divided into two groups (n = 10), that is, conventional syringe irrigation (CSI) and PUI. CHX was mixed with Rhodamine B dye and was used as the final irrigant. The teeth were sectioned at coronal, middle and apical levels and viewed under CLSM to record the penetration depth of CHX. The data were statistically analyzed using Kruskal-Wallis and Mann-Whitney U tests. The mean penetration depths of 2% CHX in coronal, middle and apical thirds were 138 µm, 80 µm and 44 µm in CSI group, respectively, whereas the mean penetration depths were 209 µm, 138 µm and 72 µm respectively in PUI group. Statistically significant difference was present between CSI group and PUI group at all three levels (p < 0.01 for coronal third and p < 0.001 for middle and apical thirds). On intragroup analysis, both groups showed statistically significant difference among three levels (p < 0.001). Penetration depth of 2% CHX into root dentinal tubules is deeper in coronal third when compared to middle and apical third. PUI aided in deeper penetration of 2% CHX into dentinal tubules when compared to conventional syringe irrigation at all three levels.

A comparative evaluation of smear layer removal by using edta, etidronic acid, and maleic acid as root canal irrigants: An in vitro scanning electron microscopic study

PubMed Central

Kuruvilla, Aby; Jaganath, Bharath Makonahalli; Krishnegowda, Sahadev Chickmagaravalli; Ramachandra, Praveen Kumar Makonahalli; Johns, Dexton Antony; Abraham, Aby

2015-01-01

Aim: The purpose of this study is to evaluate and compare the efficacy of 17% EDTA, 18% etidronic acid, and 7% maleic acid in smear layer removal using scanning electron microscopic image analysis. Materials and Methods: Thirty, freshly extracted mandibular premolars were used. The teeth were decoronated to obtain working length of 17mm and instrumentation up to 40 size (K file) with 2.5% NaOCl irrigation between each file. The samples were divided into Groups I (17% ethylenediaminetetraacetic acid (EDTA)), II (18% etidronic acid), and III (7% maleic acid) containing 10 samples each. Longitudinal sectioning of the samples was done. Then the samples were observed under scanning electron microscope (SEM) at apical, middle, and coronal levels. The images were scored according to the criteria: 1. No smear layer, 2. moderate smear layer, and 3 heavy smear layer. Statistical Analysis: Data was analyzed statistically using Kruskal–Wallis analysis of variance (ANOVA) followed by Mann-Whitney U test for individual comparisons. The level for significance was set at 0.05. Results: The present study showed that all the three experimental irrigants removed the smear layer from different tooth levels (coronal, middle, and apical). Final irrigation with 7% maleic acid is more efficient than 17% EDTA and 18% etidronic acid in the removal of smear layer from the apical third of root canal. PMID:26069414

Decision Support Systems To Manage Water Resources At Irrigation District Level In Southern Italy Using Remote Sensing Information. An Integrated Project (AQUATER)

NASA Astrophysics Data System (ADS)

Rinaldi, M.; Castrignanò, A.; Mastrorilli, M.; Rana, G.; Ventrella, D.; Acutis, M.; D'Urso, G.; Mattia, F.

2006-08-01

An efficient management of water resources is crucial point for Italy and in particular for southern areas characterized by Mediterranean climate in order to improve the economical and environmental sustainability of the agricultural activity. A three-year Project (2005-2008) has been funded by the Italian Ministry of Agriculture and Forestry Policies; it involves four Italian research institutions: the Agricultural Research Council (ISA, Bari), the National Research Council (ISSIA, Bari) and two Universities (Federico II-Naples and Milan). It is focused on the remote sensing, the plant and the climate and, for interdisciplinary relationships, the project working group consists of agronomists, engineers and physicists. The aims of the Project are: a) to produce a Decision Support System (DSS) combining remote sensing information, spatial data and simulation models to manage water resources in irrigation districts; b) to simulate irrigation scenarios to evaluate the effects of water stress on crop yield using agro-ecological indicators; c) to identify the most sensitive areas to drought risk in Southern Italy. The tools used in this Project will be: 1. Remote sensing images, topographic maps, soil and land use maps; 2. Geographic Information Systems; 3. Geostatistic methodologies; 4. Ground truth measurements (land use, canopy and soil temperatures, soil and plant water status, Normalized Difference Vegetation Index, Crop Water Stress Index, Leaf Area Index, actual evapotranspiration, crop coefficients, crop yield, agro-ecological indicators); 5. Crop simulation models. The Project is structured in four work packages with specific objectives, high degree of interaction and information exchange: 1) Remote Sensing and Image Analysis; 2) Cropping Systems; 3) Modelling and Softwares Development; 4) Stakeholders. The final product will be a DSS with the purpose of integrating remote sensing images, to estimate crop and soil variables related to drought, to assimilate these variables into a simulation model at district scale and, finally, to estimate evapotranspiration, plant water status and drought indicators. A project Web home page, a technical course about DSS for the employers of irrigation authorities and dissemination of results (meetings, publications, reports), are also planned.

Assessment of Spatio-temporal Barren-lands Expansion and Agricultural Adaptation due to Climate Change and Anthropogenic Activity: A Geospatial Approach in Hot Semi-arid Region of Maharashtra State, India

NASA Astrophysics Data System (ADS)

Roy, A.; Inamdar, A. B.

2017-12-01

Major parts of Upper Godavari River Basin are intensely drought prone and climate vulnerable in Maharashtra State, India. The economy of the state depends on the agronomic productivity of this region. So, it is necessary to monitor and regulate the effects of climate change and anthropogenic activity on agricultural land in that region. This study investigates and maps the barren-lands and alteration of agricultural lands, their decadal deviations with the multi-temporal LANDSAT satellite images; and finally quantifies the agricultural adaptations. This work involves the utilization of remote sensing and GIS tools and modeling. First, climatic trend analysis is carried out with dataset obtained from India Meteorological Department. Then, multi-temporal LANDSAT images are classified (Level I, hybrid classification technique are followed) to determine the decadal Land Use Land Cover (LULC) changes and correlated with the agricultural water demand. Finally, various LANDSAT band analysis is conducted to determine irrigated and non-irrigated cropping area estimation and identifying the agricultural adaptations. The analysis of LANDSAT images shows that barren-lands are most increased class during the study period. The overall spatial extent of barren-lands are increased drastically during the study period. The geospatial study (class-to-class conversion study) shows that, most of the conversion of the barren-lands are from the agricultural land and reserve or open forests. The barren-lands are constantly increasing and the agricultural land is linearly decreasing. Hence, there is an inverse correlation between barren-lands and agricultural land. Moreover, there is a shift to non-irrigated and less water demanding crops, from more water demanding crops, which is a noticeable adaptation. The surface-water availability is highly dependent on rainfall and/or climatic conditions. It is changing either way in a random fashion based upon the quantity of rainfall occurred in near preceding years. The agricultural lands are densely replenished around the dams and natural water bodies which serve as the water supply stations for the irrigation purposes. Hence, the study shows there are alteration in LULC, agricultural practices and surface-water availability and expansion of barren-lands.

Mapping of Temporal Surface-water Resources Availability and Agricultural Adaptability due to Climate Change and Anthropogenic Activity in a Hot Semi-arid Region of Maharashtra State, India

NASA Astrophysics Data System (ADS)

Roy, A.; Inamdar, A. B.

2016-12-01

Major part of Godavari River Basin is intensely drought prone and climate vulnerable in the Western Maharashtra State, India. The economy of the state depends on the agronomic productivity of this region. So, it is necessary to regulate the effects of existing and upcoming hydro-meteorological advances in various strata. This study investigates and maps the surface water resources availability and vegetation, their decadal deviations with multi-temporal LANDSAT images; and finally quantifies the agricultural adaptations. This work involves the utilization of Remote Sensing and GIS with Hydrological modeling. First, climatic trend analysis is carried out with NCEP dataset. Then, multi-temporal LANDSAT images are classified to determine the decadal LULC changes and correlated to the community level hydrological demand. Finally, NDVI, NDWI and SWAT model analysis are accomplished to determine irrigated and non-irrigated cropping area for identifying the agricultural adaptations. The analysis shows that the mean value of annual and monsoon rainfall is significantly decreasing, whereas the mean value of annual and summer temperature is increasing significantly and the winter temperature is decreasing. The analysis of LANDSAT images shows that the surface water availability is highly dependent on climatic conditions. Barren-lands are most dynamic during the study period followed by, vegetation, and water bodies. The spatial extent of barren-lands is increased drastically during the climate vulnerable years replacing the vegetation and surface water bodies. Hence, the barren lands are constantly increasing and the vegetation cover is linearly decreasing, whereas the water extent is changing either way in a random fashion. There appears a positive correlation between surface water and vegetation occurrence; as they are fluctuating in a similar fashion in all the years. The vegetation cover is densely replenished around the dams and natural water bodies which serve as the water supply stations for the irrigation purposes. Moreover, there is a shift to non-irrigated and less water demanding crops, from more water demanding crops, which is a conspicuous adaptation. Hence, the study shows there are alteration in meteorological predictors, land cover, agricultural practices and surface water availability.

Impacts of climate change on abstraction reliability for irrigation during droughts - Policy implications for England

NASA Astrophysics Data System (ADS)

Rey, Dolores; Holman, Ian; Rio, Marlene; Prudhomme, Christel

2017-04-01

In humid climates around the world, supplemental irrigation is critical to buffer the effects of rainfall variability and to assure crop yield and quality. In England, abstraction for irrigation is limited by: i) a maximum volumetric limit specified in the abstraction licence and ii) restrictions on abstraction imposed by the water regulator during droughts. Given regulatory efforts to secure sufficient environmental river flows and meet rising water demands due to population growth and climate change, increasing water scarcity is likely to compound the drought challenges faced by irrigated agriculture in this region. The aim of this study is to assess the impact that climate change may have on agricultural abstraction reliability in England within the context of the abstraction and drought management regimes currently in place, and how the water abstraction reform being developed by the Government could reduce the pressure on more and more limited water resources. Firstly, explanatory relationships were derived between an annual agroclimatic aridity index and actual irrigation abstraction. Secondly, the probability of annual abstraction being close to the maximum limit was calculated for each licence for the baseline (1961-90) and future (2071-2098) period. Finally, the current water resource availability triggers for mandatory abstractions restrictions on spray irrigation licences were used to assess the probability of being under restrictions during drought in each period. The results indicate a significant increase in the proportion of the licence being used in all catchments, representing the greatest risk for abstractors in the future, mainly in the most productive agricultural areas located in eastern and southern regions. In contrast, the likelihood of mandatory drought restrictions increases significantly in central and western England due to the lower buffering capacity of groundwater. Based on our findings, this paper discusses how the reform of the water abstraction licensing system being currently designed could help farmers to reduce their water availability risks. For instance, our analysis shows that a huge percentage of licenses in the country are hardly ever used, and hence the potential for reallocation (through water trading or other mechanisms) is worth exploring. Our results highlight the increasing water availability risks for irrigators in this country, and the need of the farming community and the regulator to adapt and collaborate to reduce the impacts and to increase drought resilience and hence food security.

Assessing accumulated hard-tissue debris using micro-computed tomography and free software for image processing and analysis.

PubMed

De-Deus, Gustavo; Marins, Juliana; Neves, Aline de Almeida; Reis, Claudia; Fidel, Sandra; Versiani, Marco A; Alves, Haimon; Lopes, Ricardo Tadeu; Paciornik, Sidnei

2014-02-01

The accumulation of debris occurs after root canal preparation procedures specifically in fins, isthmus, irregularities, and ramifications. The aim of this study was to present a step-by-step description of a new method used to longitudinally identify, measure, and 3-dimensionally map the accumulation of hard-tissue debris inside the root canal after biomechanical preparation using free software for image processing and analysis. Three mandibular molars presenting the mesial root with a large isthmus width and a type II Vertucci's canal configuration were selected and scanned. The specimens were assigned to 1 of 3 experimental approaches: (1) 5.25% sodium hypochlorite + 17% EDTA, (2) bidistilled water, and (3) no irrigation. After root canal preparation, high-resolution scans of the teeth were accomplished, and free software packages were used to register and quantify the amount of accumulated hard-tissue debris in either canal space or isthmus areas. Canal preparation without irrigation resulted in 34.6% of its volume filled with hard-tissue debris, whereas the use of bidistilled water or NaOCl followed by EDTA showed a reduction in the percentage volume of debris to 16% and 11.3%, respectively. The closer the distance to the isthmus area was the larger the amount of accumulated debris regardless of the irrigating protocol used. Through the present method, it was possible to calculate the volume of hard-tissue debris in the isthmuses and in the root canal space. Free-software packages used for image reconstruction, registering, and analysis have shown to be promising for end-user application. Copyright © 2014. Published by Elsevier Inc.

A Novel Wound Retractor Combining Continuous Irrigation and Barrier Protection Reduces Incisional Contamination in Colorectal Surgery.

PubMed

Papaconstantinou, Harry T; Ricciardi, Rocco; Margolin, David A; Bergamaschi, Roberto; Moesinger, Robert C; Lichliter, Warren E; Birnbaum, Elisa H

2018-03-09

Surgical site infection (SSI) remains a persistent and morbid problem in colorectal surgery. Key to its pathogenesis is the degree of intraoperative bacterial contamination at the surgical site. The purpose of this study was to evaluate a novel wound retractor at reducing bacterial contamination. A prospective multicenter pilot study utilizing a novel wound retractor combining continuous irrigation and barrier protection was conducted in patients undergoing elective colorectal resections. Culture swabs were collected from the incision edge prior to device placement and from the exposed and protected incision edge prior to device removal. The primary and secondary endpoints were the rate of enteric and overall bacterial contamination on the exposed incision edge as compared to the protected incision edge, respectively. The safety endpoint was the absence of serious device-related adverse events. A total of 86 patients were eligible for analysis. The novel wound retractor was associated with a 66% reduction in overall bacterial contamination at the protected incision edge compared to the exposed incision edge (11.9 vs. 34.5%, P < 0.001), and 71% reduction in enteric bacterial contamination (9.5% vs. 33.3%, P < 0.001). The incisional SSI rate was 2.3% in the primary analysis and 1.2% in those that completed the protocol. There were no adverse events attributed to device use. A novel wound retractor combining continuous irrigation and barrier protection was associated with a significant reduction in bacterial contamination. Improved methods to counteract wound contamination represent a promising strategy for SSI prevention (NCT 02413879).

Second-generation Platelet Concentrate (Platelet-rich Fibrin) as a Scaffold in Regenerative Endodontics: A Case Series.

PubMed

Bakhtiar, Hengameh; Esmaeili, Shahram; Fakhr Tabatabayi, Setareh; Ellini, Mohammad Reza; Nekoofar, Mohammad Hossein; Dummer, Paul M H

2017-03-01

The purpose of this case series was to report the clinical and radiographic results of a pulp regenerative procedure using platelet-rich fibrin (PRF), a second-generation platelet concentrate, in immature teeth with necrotic pulps. Root canal revascularization using PRF was performed on 4 immature teeth with necrotic pulps. After access cavity preparation, the root canals were irrigated with low concentration sodium hypochlorite solution (1.5% sodium hypochlorite [20 mL/canal, 5 minutes]) and then irrigated with saline (20 mL/canal, 5 minutes). Equal proportions (167 mg) of ciprofloxacin, metronidazole, and cefaclor were mixed and diluted to a final concentration of 1 g/mL. Finally, the canal was sealed with 3-4 mm of a temporary restorative material, and patients were dismissed for 2 to 3 weeks. At the second appointment, 9 mL of the patient's whole blood was obtained and centrifuged to prepare a PRF clot. Canals were irrigated with 17% EDTA, and a sharp spreader was inserted beyond the apex. Then, the PRF clot was placed inside the root canals, and Biodentine (Septodont, Saint-Maur, France) was placed directly over the PRF. The teeth were restored permanently with glass ionomer cement and composite resin. Clinical examinations revealed that all cases were asymptomatic at the recall appointments at 1, 3, 6, 12, and 18 months. Radiographs revealed resolution of the periapical lesions, further root development, and apical closure in all cases. On the basis of the short-term results up to 12 months, PRF clots acted as successful scaffolds for the regeneration of pulpal contents in immature teeth with necrotic pulps. Copyright © 2016 American Association of Endodontists. All rights reserved.

Assessing the Use of Remote Sensing and a Crop Growth Model to Improve Modeled Streamflow in Central Asia

NASA Astrophysics Data System (ADS)

Richey, A. S.; Richey, J. E.; Tan, A.; Liu, M.; Adam, J. C.; Sokolov, V.

2015-12-01

Central Asia presents a perfect case study to understand the dynamic, and often conflicting, linkages between food, energy, and water in natural systems. The destruction of the Aral Sea is a well-known environmental disaster, largely driven by increased irrigation demand on the rivers that feed the endorheic sea. Continued reliance on these rivers, the Amu Darya and Syr Darya, often place available water resources at odds between hydropower demands upstream and irrigation requirements downstream. A combination of tools is required to understand these linkages and how they may change in the future as a function of climate change and population growth. In addition, the region is geopolitically complex as the former Soviet basin states develop management strategies to sustainably manage shared resources. This complexity increases the importance of relying upon publically available information sources and tools. Preliminary work has shown potential for the Variable Infiltration Capacity (VIC) model to recreate the natural water balance in the Amu Darya and Syr Darya basins by comparing results to total terrestrial water storage changes observed from NASA's Gravity Recovery and Climate Experiment (GRACE) satellite mission. Modeled streamflow is well correlated to observed streamflow at upstream gauges prior to the large-scale expansion of irrigation and hydropower. However, current modeled results are unable to capture the human influence of water use on downstream flow. This study examines the utility of a crop simulation model, CropSyst, to represent irrigation demand and GRACE to improve modeled streamflow estimates in the Amu Darya and Syr Darya basins. Specifically we determine crop water demand with CropSyst utilizing available data on irrigation schemes and cropping patterns. We determine how this demand can be met either by surface water, modeled by VIC with a reservoir operation scheme, and/or by groundwater derived from GRACE. Finally, we assess how the inclusion of CropSyst and groundwater to model and meet irrigation demand improves modeled streamflow from VIC throughout the basins. The results of this work are integrated into a decision support platform to assist the basin states in understanding water availability and the impact of management decisions on available resources.

Improving irrigation efficiency : the need for a relevant sequence of the management tools

NASA Astrophysics Data System (ADS)

Fayolle, Y.

2009-04-01

With 70 % of worldwide withdrawals, irrigation efficiency is a key issue in the overall problem of water resources. Management of water dedicated to agriculture should be improved to secure food production and save water to deal with increasing domestic and industrial demands. This paper is based on the results of a collaborative research project conducted in India with a local NGO (the Aga Khan Rural Support Programme, AKRSP(I)) during which GIS were tested. It is aimed at analyzing the efficiency of water usage in a water development programme conducted by the partner NGO in the semi-arid margins of Gujarat state. The analysis raises the question of the articulation of legal, institutional, economical, and technical tools to improve water efficiency. The NGO supervises the construction of surface water harvesting structures for irrigation purposes. Following a participatory approach, it creates and trains user groups to which the management of dams would then be devolved. User group membership depends on financial contribution to the building costs. A legal vacuum regarding surface water management combined with unequal investment capacities favor the concentration of water resources in the hands of a limited number of farmers. This causes low water use efficiency, irrigation choices being mostly oriented to high water consumptive crops and recipient farmers showing no interest in investing in water saving techniques. Our observations favor equality of access and paying more attention to the sequence in which management tools are articulated. On a national scale, as a prerequisite, water user rights as well as NGO's intervention legal framework should be clarified. On a project scale, before construction, information systems could help to identify all potential beneficiaries and optimize equality of access. It aims at reducing the volume of water per farmer to encourage them to irrigate low water consumptive crops and invest in water saving techniques. Depending on individual investment capacities, financial support could be proposed to favor investments in micro-irrigation devices. Finally, we suggest delaying the use of economic tools, giving up financial participation to the building costs (to limit their discriminating effect on user groups access), and limiting their applications to watering charges to cover maintenance expenses.

Efficacy of chlorhexidine as a final irrigant in one-visit root canal treatment: a prospective comparative study.

PubMed

Miçooğullar Kurt, S; Çalışkan, M K

2018-03-30

To evaluate postoperative pain and radiographic evidence of periapical healing in teeth with apical periodontitis treated in one visit with an additional final irrigation using 2% chlorhexidine (CHX) and to compare the results with conventional two-visit root canal treatment (RCT) with an intracanal calcium hydroxide (CH) dressing as a control group. Ninety asymptomatic maxillary anterior teeth with periapical lesions were treated by a single operator. Root canals were prepared using the step-back technique with manual instrumentation with 2.5% NaOCl and 5% EDTA as irrigants. Half of the teeth were randomly assigned to the one-visit (OV) group and received an additional final rinse with 2% CHX before canal filling. The other teeth were treated in two visits (TV) with a CH paste made by mixing CH powder and distilled water as an interappointment dressing. All patients were recalled and investigated clinically and radiographically for 24 months. Postoperative pain at 24-48 h and changes in apical bone density indicating radiographic healing were evaluated statistically using the Mann-Whitney U-test followed by the Friedman and the Wilcoxon tests (α = 0.05). There were no significant differences between two groups regarding the incidence of postoperative pain at 24 h (OV group 50% no pain, 47.6% mild, 2.4% moderate pain/TV group 55% no pain, 42.5% mild, 2.5% moderate pain) and at 48 h (OV group 95% no pain, 5% mild pain/TV group 98% no pain, 2% mild pain). None of the patients reported severe postoperative pain, swelling and/or flare-ups during the follow-up period. There was no significant difference in the radiographic healing rates (OV group 97.6% PAI 1 and/or PAI 2 and 2.4% PAI 3/TV group 95% PAI 1 and/or PAI 2 and 5% PAI 3; P > 0.05). Both groups provided favourable and similar postoperative pain and periapical healing rates at 24 months. Thus, one-visit RCT with a final rinse with 2% CHX is an acceptable alternative to two-visit RCT with CH as temporary dressing in maxillary anterior teeth. © 2018 International Endodontic Journal. Published by John Wiley & Sons Ltd.

Zinc movement in sewage-sludge-treated soils as influenced by soil properties, irrigation water quality, and soil moisture level

USGS Publications Warehouse

Welch, J.E.; Lund, L.J.

1989-01-01

A soil column study was conducted to assess the movement of Zn in sewage-sludge-amended soils. Varables investigated were soil properties, irrigation water quality, and soil moisture level. Bulk samples of the surface layer of six soil series were packed into columns, 10.2 cm in diameter and 110 cm in length. An anaerobically digested municipal sewage sludge was incorporated into the top 20 cm of each column at a rate of 300 mg ha-1. The columns were maintained at moisture levels of saturation and unsaturation and were leached with two waters of different quality. At the termination of leaching, the columns were cut open and the soil was sectioned and analyzed. Zinc movement was evaluated by mass balance accounting and correlation and regression analysis. Zinc movement in the unsaturated columns ranged from 3 to 30 cm, with a mean of 10 cm. The difference in irrigation water quality did not have an effect on Zn movement. Most of the Zn applied to the unsaturated columns remained in the sludge-amended soil layer (96.1 to 99.6%, with a mean of 98.1%). The major portion of Zn leached from the sludge-amended soil layer accumulated in the 0- to 3-cm depth (35.7 to 100%, with a mean of 73.6%). The mean final soil pH values decreased in the order: saturated columns = sludge-amended soil layer > untreated soils > unsaturated columns. Total Zn leached from the sludge-amended soil layer was correlated negatively at P = 0.001 with final pH (r = -0.85). Depth of Zn movement was correlated negatively at P = 0.001 with final pH (r = -0.91). Multiple linear regression analysis showed that the final pH accounted for 72% of the variation in the total amounts of Zn leached from the sludge-amended soil layer of the unsaturated columns and accounted for 82% of the variation in the depth of Zn movement among the unsaturated columns. A significant correlation was not found between Zn and organic carbon in soil solutions, but a negative correlation significant at P = 0.001 was found between pH and Zn (r = -0.61).

Considerations on methodological challenges for water footprint calculations.

PubMed

Thaler, S; Zessner, M; De Lis, F Bertran; Kreuzinger, N; Fehringer, R

2012-01-01

We have investigated how different approaches for water footprint (WF) calculations lead to different results, taking sugar beet production and sugar refining as examples. To a large extent, results obtained from any WF calculation are reflective of the method used and the assumptions made. Real irrigation data for 59 European sugar beet growing areas showed inadequate estimation of irrigation water when a widely used simple approach was used. The method resulted in an overestimation of blue water and an underestimation of green water usage. Dependent on the chosen (available) water quality standard, the final grey WF can differ up to a factor of 10 and more. We conclude that further development and standardisation of the WF is needed to reach comparable and reliable results. A special focus should be on standardisation of the grey WF methodology based on receiving water quality standards.

Irrigation Training Manual. Planning, Design, Operation, and Management of Small-Scale Irrigation Systems [and] Irrigation Reference Manual. A Technical Reference to Be Used with the Peace Corps Irrigation Training Manual T0076 in the Selection, Planning, Design, Operation, and Management of Small-Scale Irrigation Systems.

ERIC Educational Resources Information Center

Salazar, LeRoy; And Others

This resource for trainers involved in irrigated agriculture training for Peace Corps volunteers consists of two parts: irrigation training manual and irrigation reference manual. The complete course should fully prepare volunteers serving as irrigation, specialists to plan, implement, evaluate and manage small-scale irrigation projects in arid,…

NEPA Manual for Materiel Acquisition

DTIC Science & Technology

2000-11-01

of it in the final EIS. For example, a commentor on a draft EIS on a proposal for a pumped storage power facility might suggest that the applicant’s...strips around streams and replacing inorganic fertilizers with animal manures, and reducing soil erosion through modified tillage and irrigation...available items and products for military application (for example, sportsman’s products and wear such as holsters , shotguns, sidearms, protective shields

Endodontic Treatment of an Autogenous Transplanted Tooth Using an Er,Cr:YSGG Laser and Radial Firing Tips: Case Report.

PubMed

Martins, Miguel Rodrigues; Lima, Rita C; Pina-Vaz, Irene; Carvalho, Manuel Fontes; Gutknecht, Norbert

2016-10-01

Although several surgical techniques have been reported, no study has yet reported alternative strategies for endodontic treatment of autogenous transplanted teeth. Therefore, the aim of this clinical report is to present the long-term endodontic outcome of a nonvital autogenously transplanted third molar treated with an Er,Cr:YSGG laser and radial firing tips (RFTs). Autogenous tooth transplantation can be considered an alternative to restore edentulous areas and, in donor's teeth with complete root formation, root canal treatment should be performed up to 14 days following transplantation. In the present case report, the patient returned only after 6 months, with clinical and radiological signs of apical periodontitis (AP) associated with the transplanted tooth. Instead of traditional endodontic chemical irrigants or medications, the protocol for smear-layer removal and root canal disinfection was based on intracanal irradiation with an Er,Cr:YSGG laser and RFTs. After 3-years' follow-up, the complete reestablishment of the periodontal ligament and the arrest of the resorptive process could be noticed. This protocol has shown to be effective for the endodontic treatment of a transplanted multi-rooted tooth with AP. Further randomized clinical trials should be conducted to clearly demonstrate the effectiveness of this laser-assisted endodontic protocol.

Adaptive Probabilistic Protocols for Advanced Networks/Assuring the Integrity of Highly Decentralized Communications Systems

DTIC Science & Technology

2005-03-01

to obtain a protocol customized to the needs of a specific setting, under control of an automated theorem proving system that can guarantee...new “compositional” method for protocol design and implementation, in which small microprotocols are combined to obtain a protocol customized to the...and Network Centric Enterprise (NCES) visions. This final report documents a wide range of contributions and technology transitions, including: A

Influence of the Apical Preparation Size and the Irrigant Type on Bacterial Reduction in Root Canal-treated Teeth with Apical Periodontitis.

PubMed

Rodrigues, Renata Costa Val; Zandi, Homan; Kristoffersen, Anne Karin; Enersen, Morten; Mdala, Ibrahimu; Ørstavik, Dag; Rôças, Isabela N; Siqueira, José F

2017-07-01

This clinical study evaluated the influence of the apical preparation size using nickel-titanium rotary instrumentation and the effect of a disinfectant on bacterial reduction in root canal-treated teeth with apical periodontitis. Forty-three teeth with posttreatment apical periodontitis were selected for retreatment. Teeth were randomly divided into 2 groups according to the irrigant used (2.5% sodium hypochlorite [NaOCl], n = 22; saline, n = 21). Canals were prepared with the Twisted File Adaptive (TFA) system (SybronEndo, Orange, CA). Bacteriological samples were taken before preparation (S1), after using the first instrument (S2), and then after the third instrument of the TFA system (S3). In the saline group, an additional sample was taken after final irrigation with 1% NaOCl (S4). DNA was extracted from the clinical samples and subjected to quantitative real-time polymerase chain reaction to evaluate the levels of total bacteria and streptococci. S1 from all teeth were positive for bacteria. Preparation to the first and third instruments from the TFA system showed a highly significant intracanal bacterial reduction regardless of the irrigant (P < .01). Apical enlargement to the third instrument caused a significantly higher decrease in bacterial counts than the first instrument (P < .01). Intergroup comparison revealed no significant difference between NaOCl and saline after the first instrument (P > .05). NaOCl was significantly better than saline after using the largest instrument in the series (P < .01). Irrespective of the type of irrigant, an increase in the apical preparation size significantly enhanced root canal disinfection. The disinfecting benefit of NaOCl over saline was significant at large apical preparation sizes. Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Exploring synergistic benefits of Water-Food-Energy Nexus through multi-objective reservoir optimization schemes.

PubMed

Uen, Tinn-Shuan; Chang, Fi-John; Zhou, Yanlai; Tsai, Wen-Ping

2018-08-15

This study proposed a holistic three-fold scheme that synergistically optimizes the benefits of the Water-Food-Energy (WFE) Nexus by integrating the short/long-term joint operation of a multi-objective reservoir with irrigation ponds in response to urbanization. The three-fold scheme was implemented step by step: (1) optimizing short-term (daily scale) reservoir operation for maximizing hydropower output and final reservoir storage during typhoon seasons; (2) simulating long-term (ten-day scale) water shortage rates in consideration of the availability of irrigation ponds for both agricultural and public sectors during non-typhoon seasons; and (3) promoting the synergistic benefits of the WFE Nexus in a year-round perspective by integrating the short-term optimization and long-term simulation of reservoir operations. The pivotal Shihmen Reservoir and 745 irrigation ponds located in Taoyuan City of Taiwan together with the surrounding urban areas formed the study case. The results indicated that the optimal short-term reservoir operation obtained from the non-dominated sorting genetic algorithm II (NSGA-II) could largely increase hydropower output but just slightly affected water supply. The simulation results of the reservoir coupled with irrigation ponds indicated that such joint operation could significantly reduce agricultural and public water shortage rates by 22.2% and 23.7% in average, respectively, as compared to those of reservoir operation excluding irrigation ponds. The results of year-round short/long-term joint operation showed that water shortage rates could be reduced by 10% at most, the food production rate could be increased by up to 47%, and the hydropower benefit could increase up to 9.33 million USD per year, respectively, in a wet year. Consequently, the proposed methodology could be a viable approach to promoting the synergistic benefits of the WFE Nexus, and the results provided unique insights for stakeholders and policymakers to pursue sustainable urban development plans. Copyright © 2018 Elsevier B.V. All rights reserved.

Intraosseous generation of heat during guided surgical drilling: an ex vivo study of the effect of the temperature of the irrigating fluid.

PubMed

Boa, Kristof; Barrak, Ibrahim; Varga, Endre; Joob-Fancsaly, Arpad; Varga, Endre; Piffko, Jozsef

2016-10-01

We measured the rise in the intraosseous temperature caused by freehand drilling or drilling through a surgical guide, by comparing different temperatures of irrigation fluid (10°C, 15°C, and 20°C), for every step of the drilling sequence (diameters 2.0, 2.5, 3.0, and 3.5mm) and using a constant drilling speed of 1200rpm. The axial load was controlled at 2.0kg. Bovine ribs were used as test models. In the guided group we used 3-dimensional printed surgical guides and temperature was measured with a thermocouple. The significance of differences was assessed with the Kruskal-Wallis analysis of variance. Guided drilling with 10°C irrigation yielded a significantly lower increment in temperature than the 20°C-guided group. When compared with the 20°C freehand group, the reduction in temperature in the 10°C guided group was significantly more pronounced at all diameters except 3.5mm. Finally, when the 10°C-guided group was compared with the 15°C groups, the temperature rise was significantly less at 2.5 and 3.0mm than with the guided technique, and at 3.0mm compared with the freehand technique. We suggest that the use of 10°C pre-cooled irrigation fluid is superior to warmer fluid for keeping temperature down, and this reduces the difference between guided and freehand drilling. Copyright © 2016 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

Transfer of antibiotics from wastewater or animal manure to soil and edible crops.

PubMed

Pan, Min; Chu, L M

2017-12-01

Antibiotics are added to agricultural fields worldwide through wastewater irrigation or manure application, resulting in antibiotic contamination and elevated environmental risks to terrestrial environments and humans. Most studies focused on antibiotic detection in different matrices or were conducted in a hydroponic environment. Little is known about the transfer of antibiotics from antibiotic-contaminated irrigation wastewater and animal manure to agricultural soil and edible crops. In this study, we evaluated the transfer of five different antibiotics (tetracycline, sulfamethazine, norfloxacin, erythromycin, and chloramphenicol) to different crops under two levels of antibiotic-contaminated wastewater irrigation and animal manure fertilization. The final distribution of tetracycline (TC), norfloxacin (NOR) and chloramphenicol (CAP) in the crop tissues under these four treatments were as follows: fruit > leaf/shoot > root, while an opposite order was found for sulfamethazine (SMZ) and erythromycin (ERY): root > leaf/shoot > fruit. The growth of crops could accelerate the dissipation of antibiotics by absorption from contaminated soil. A higher accumulation of antibiotics was observed in crop tissues under the wastewater treatment than under manure treatment, which was due to the continual irrigation that increased adsorption in soil and uptake by crops. The translocation of antibiotics in crops mainly depended on their physicochemical properties (e.g. log K ow ), crop species, and the concentrations of antibiotics applied to the soil. The levels of antibiotics ingested through the consumption of edible crops under the different treatments were much lower than the acceptable daily intake (ADI) levels. Copyright © 2017 Elsevier Ltd. All rights reserved.

Multiscale object-based drought monitoring and comparison in rainfed and irrigated agriculture from Landsat 8 OLI imagery

NASA Astrophysics Data System (ADS)

Ozelkan, Emre; Chen, Gang; Ustundag, Burak Berk

2016-02-01

Drought is a rapidly rising environmental issue that can cause hardly repaired or unrepaired damages to the nature and socio-economy. This is especially true for a region that features arid/semi-arid climate, including the Turkey's most important agricultural district - Southeast Anatolia. In this area, we examined the uncertainties of applying Landsat 8 Operational Land Imager (OLI) NDVI data to estimate meteorological drought - Standardized Precipitation Index (SPI) - measured from 31 in-situ agro-meteorological monitoring stations during spring and summer of 2013 and 2014. Our analysis was designed to address two important, yet under-examined questions: (i) how does the co-existence of rainfed and irrigated agriculture affect remote sensing drought monitoring in an arid/semi-arid region? (ii) What is the role of spatial scale in drought monitoring using a GEOBIA (geographic object-based image analysis) framework? Results show that spatial scale exerted a higher impact on drought monitoring especially in the drier year 2013, during which small scales were found to outperform large scales in general. In addition, consideration of irrigated and rainfed areas separately ensured a better performance in drought analysis. Compared to the positive correlations between SPI and NDVI over the rainfed areas, negative correlations were determined over the irrigated agricultural areas. Finally, the time lag effect was evident in the study, i.e., strong correlations between spring SPI and summer NDVI in both 2013 and 2014. This reflects the fact that spring watering is crucial for the growth and yield of the major crops (i.e., winter wheat, barley and lentil) cultivated in the region.

Comparison of the Antimicrobial Efficacy of the EndoVac System and Conventional Needle Irrigation in Primary Molar Root Canals.

PubMed

Buldur, Burak; Kapdan, Arife

The purpose of this study was to compare the antimicrobial efficacy of the EndoVac system and conventional needle irrigation to eliminate E faecalis in primary molar root canals. 60 extracted human primary second molar roots were instrumented up to an apical size .04/35 and randomly divided into two groups; Group 1: conventional needle (n=30) and Group 2: EndoVac (n=30), and four subgroups (two experimental subgroups; (a) 2.5% sodium hypochlorite (NaOCl) + ethylenediaminetetraacetic acid (EDTA) (n=20), (b) ozonated water (OW) + EDTA (n=20), and control groups (c) 5.25% NaOCl (n=10) and (d) saline (n=10). All roots were sterilized and then inoculated with E.faecalis. Before and after final irrigation procedures, root canals were sampled and the grown colony forming units (CFUs) were counted. Data were analyzed by Kruskall-Wallis and Mann-Whitney U tests using a 0.05 significance level. The EndoVac reduced more bacteria than the conventional needle did but it was not statistically significant (p>0.05). NaOCl alone or followed by EDTA totally eliminated bacteria. OW + EDTA showed higher reduction of bacteria but could not totally eliminate bacterias. In the context of bacterial elimination, the EndoVac was not significantly better than the conventional needle. Although, there were fewer CFU/mg when using EndoVac, there was not any statistically significant superiority to conventional needle irrigation. An OW+EDTA regimen showed antibacterial effect in the primary molar root canals but it was significantly less effective than NaOCl+EDTA.

Evaluation of Populus and Salix continuously irrigated with landfill leachate II. soils and early tree development.

PubMed

Zalesny, Ronald S; Bauer, Edmund O

2007-01-01

Soil contaminant levels and early tree growth data are helpful for assessing phytoremediation systems. Populus (DN17, DN182, DN34, NM2, and NM6) and Salix (94003, 94012, S287, S566, and SX61) genotypes were irrigated with landfill leachate or municipal water and tested for differences in (1) element concentrations (P, K, Ca, Mg, S, Zn, B, Mn, Fe, Cu, Al, and Na) of a topsoil layer and a layer of sand in tanks with a cover crop of trees or no trees and (2) height, diameter, volume, and dry mass of leaves, stems, and roots. Trees were irrigated with leachate or water during the final 12 wk of the 18-wk study. Differences in most soil element concentrations were negligible (P > 0.05) for irrigation treatments and cover main effects. Phosphorous, K, Mg, S, Zn, Mn, Fe, and Al concentrations were greater in topsoil than sand (P = 0.0011 for Mg; P < 0.0001 for others). There was broad variation between genera and among clones for all growth traits. The treatment x clone interaction governed height, volume, and root dry mass, with (94012, SX61), (NM2, S566, SX61), and (S287, S566) exhibiting the greatest levels, respectively,following leachate application. Given the broad amount of variability among and within these genera, there is great potential for the identification and selection of specific genotypes with a combination of elevated phytoremediation capabilities and tree yield. From a practical standpoint, these results may be used as a baseline for the development of future remediation systems.

Quantitative analysis of the growth of Salmonella stanley during alfalfa sprouting and evaluation of Enterobacter aerogenes as its surrogate.

PubMed

Liu, Bin; Schaffner, Donald W

2007-02-01

Raw seed sprouts have been implicated in several food poisoning outbreaks in the last 10 years. Few studies have included investigations of factors influencing the effectiveness of testing spent irrigation water, and in no studies to date has a nonpathogenic surrogate been identified as suitable for large-scale irrigation water testing trials. Alfalfa seeds were inoculated with Salmonella Stanley or its presumptive surrogate (nalidixic acid-resistant Enterobacter aerogenes) at three concentrations (-3, -30, and -300 CFU/g) and were then transferred into either flasks or a bench top-scale sprouting chamber. Microbial concentrations were determined in seeds, sprouts, and irrigation water at various times during a 4-day sprouting process. Data were fit to logistic regression models, and growth rates and maximum concentrations were compared using the generalized linear model procedure of SAS. No significant differences in growth rates were observed among samples taken from flasks or the chamber. Microbial concentrations in irrigation water were not significantly different from concentrations in sprout samples obtaihed at the same time. E. aerogenes concentrations were similar to those of Salmonella Stanley at corresponding time points for all three inoculum concentrations. Growth rates were also constant regardless of inoculum concentration or strain, except that lower inoculum concentrations resulted in lower final concentrations proportional to their initial concentrations. This research demonstrated that a nonpathogenic easy-to-isolate surrogate (nalidixic acid-resistant E. aerogenes) provides results similar to those obtained with Salmonella Stanley, supporting the use of this surrogate in future large-scale experiments.

Estimating the own-price elasticity of demand for irrigation water in the Musi catchment of India

NASA Astrophysics Data System (ADS)

Davidson, Brian; Hellegers, Petra

2011-10-01

SummaryAs irrigation water is an input into a production process, its demand must be 'derived'. According to theory, a derived demand schedule should be downward sloping and dependent on the outputs produced from it, the prices of other inputs and the price of the water itself. Problems arise when an attempt is made to estimate the demand for irrigation water and the resulting own-price elasticity of demand, as the uses to which water is put are spatially, temporarily and geographically diverse. Because water is not generally freely traded, what normally passes for an estimate of the own-price elasticity of demand for irrigation water is usually a well argued assumption or an estimate that is derived from a simulation model of a hypothesized producer. Such approaches tend to provide an inadequate explanation of what is an extremely complex and important relationship. An adequate explanation of the relationship between the price and the quantity demanded of water should be one that not only accords with the theoretical expectations, but also accounts for the diversity of products produced from water (which includes the management practices of farmers), the seasons in which it is used and over the region within which it is used. The objective in this article is to present a method of estimating the demand curve for irrigation water. The method uses actual field data which is collated using the Residual Method to determine the value of the marginal product of water deployed over a wide range of crops, seasons and regions. These values of the marginal products, all which must lie of the input demand schedule for water, are then ordered from the highest value to the lowest. Then, the amount of irrigation water used for each product, in each season and in each region is cumulatively summed over the range of uses according to the order of the values of the marginal products. This data, once ordered, is then used to econometrically estimate the demand schedule from which the own-price elasticity of demand for irrigation water can be derived. To illustrate the method, the values of the marginal product of water deployed in the Musi catchment in India are used to determine an own-price elasticity of demand for irrigation water which has some positive value to producers of approximately -0.64. For water that is most highly valued, the elasticity was found to be highly elastic at -2.12, while less valued water used in agriculture was far more inelastic at -0.44. Finally, for almost 36% of water deployed in the catchment the elasticity was logically determined to be perfectly elastic.

Comparison of Irrigation Water Use Estimates Calculated from Remotely Sensed Irrigated Acres and State Reported Irrigated Acres in the Lake Altus Drainage Basin, Oklahoma and Texas, 2000 Growing Season

USGS Publications Warehouse

Masoner, J.R.; Mladinich, C.S.; Konduris, A.M.; Smith, S. Jerrod

2003-01-01

Increased demand for water in the Lake Altus drainage basin requires more accurate estimates of water use for irrigation. The U.S. Geological Survey, in cooperation with the U.S. Bureau of Reclamation, is investigating new techniques to improve water-use estimates for irrigation purposes in the Lake Altus drainage basin. Empirical estimates of reference evapotranspiration, crop evapotranspiration, and crop irrigation water requirements for nine major crops were calculated from September 1999 to October 2000 using a solar radiation-based evapotranspiration model. Estimates of irrigation water use were calculated using remotely sensed irrigated crop acres derived from Landsat 7 Enhanced Thematic Mapper Plus imagery and were compared with irrigation water-use estimates calculated from irrigated crop acres reported by the Oklahoma Water Resources Board and the Texas Water Development Board for the 2000 growing season. The techniques presented will help manage water resources in the Lake Altus drainage basin and may be transferable to other areas with similar water management needs. Irrigation water use calculated from the remotely sensed irrigated acres was estimated at 154,920 acre-feet; whereas, irrigation water use calculated from state reported irrigated crop acres was 196,026 acre-feet, a 23 percent difference. The greatest difference in irrigation water use was in Carson County, Texas. Irrigation water use for Carson County, Texas, calculated from the remotely sensed irrigated acres was 58,555 acrefeet; whereas, irrigation water use calculated from state reported irrigated acres was 138,180 acre-feet, an 81 percent difference. The second greatest difference in irrigation water use occurred in Beckham County, Oklahoma. Differences between the two irrigation water use estimates are due to the differences of irrigated crop acres derived from the mapping process and those reported by the Oklahoma Water Resources Board and Texas Water Development Board.

Kansas environmental and resource study: A Great Plains model. Extraction of agricultural statistics from ERTS-1 data of Kansas. [wheat inventory and agriculture land use

NASA Technical Reports Server (NTRS)

Morain, S. A. (Principal Investigator); Williams, D. L.

1974-01-01

The author has identified the following significant results. Wheat area, yield, and production statistics as derived from satellite image analysis, combined with a weather model, are presented for a ten county area in southwest Kansas. The data (representing the 1972-73 crop year) are compared for accuracy against both the USDA August estimate and its final (official) tabulation. The area estimates from imagery for both dryland and irrigated winter wheat were within 5% of the official figures for the same area, and predated them by almost one year. Yield on dryland wheat was estimated by the Thompson weather model to within 0.1% of the observed yield. A combined irrigated and dryland wheat production estimate for the ten county area was completed in July, 1973 and was within 1% of the production reported by USDA in February, 1974.

Western water and climate change

USGS Publications Warehouse

Dettinger, Michael; Udall, Bradley; Georgakakos, Aris P.

2015-01-01

In this context, four iconic river basins offer glimpses into specific challenges that climate change may bring to the West. The Colorado River is a system in which overuse and growing demands are projected to be even more challenging than climate-change-induced flow reductions. The Rio Grande offers the best example of how climate-change-induced flow declines might sink a major system into permanent drought. The Klamath is currently projected to face the more benign precipitation future, but fisheries and irrigation management may face dire straits due to warming air temperatures, rising irrigation demands, and warming waters in a basin already hobbled by tensions between endangered fisheries and agricultural demands. Finally, California's Bay-Delta system is a remarkably localized and severe weakness at the heart of the region's trillion-dollar economy. It is threatened by the full range of potential climate-change impacts expected across the West, along with major vulnerabilities to increased flooding and rising sea levels.

Genotoxicity of soil from farmland irrigated with wastewater using three plant bioassays.

PubMed

Cabrera, G L; Rodriguez, D M

1999-05-19

Three well known plant bioassays, the Allium root chromosome aberration (AL-RAA) assay, the Tradescantia micronucleus (Trad-MCN) assay, and the Tradescantia stamen hair (Trad-SHM) mutation assay were validated in 1991 by the International Programme on Chemical Safety (IPCS) under the auspices of the World Health Organization, and the United Nations Environment Programme (UNEP). These plant bioassays have proven to be efficient tests for chemical screening and especially for in situ monitoring for genotoxicity of environmental pollutants. As a result of this validation study, standard protocols of these three plant bioassays were used by some of the 11 participating countries in the IPCS to carry on genotoxicity tests on air, water and soil as a follow up activity. In the city of Queretaro, Mexico, wastewater coming from both industrial and domestic sources and without any treatment is used to irrigate the farm crops, polluting the soil. Potentially the pollutants could reach the food chain. For the above reason, soil irrigated with wastewater was sampled and monitored for the presence of genotoxic agents using the above three bioassays. Extracts from soil samples were made using distilled water and organic solvents by shaking the sample for about 12 h under a relatively low temperature (15-20 degrees C). Plant cuttings of Tradescantia or the roots of Allium were treated by submerging them in the extracts. Three replicates of each sample were analyzed in each of the three bioassays. Extracts using DMSO, ethanol and distilled water tested positive in the three bioassays and there were no differences for the genotoxicity of the extracts with the different solvents. Copyright 1999 Elsevier Science B.V.

Comparative evaluation of calcium hypochlorite and sodium hypochlorite associated with passive ultrasonic irrigation on antimicrobial activity of a root canal system infected with Enterococcus faecalis: an in vitro study.

PubMed

de Almeida, Ana Paula; Souza, Matheus Albino; Miyagaki, Daniela Cristina; Dal Bello, Yuri; Cecchin, Doglas; Farina, Ana Paula

2014-12-01

The purpose of this study was to compare in vitro the effectiveness of calcium hypochlorite (Ca[OCl]2) and sodium hypochlorite (NaOCl) associated with passive ultrasonic irrigation in root canals of bovine teeth infected with Enterococcus faecalis. The root canals of 60 single-rooted bovine extracted teeth were enlarged up to a file 45, autoclaved, inoculated with Enterococcus faecalis, and incubated for 30 days. The samples were divided into 6 groups (n = 10) according to the protocol for decontamination: G1: no treatment; G2: distilled water; G3: 2.5% NaOCl; G4: 2.5% Ca(OCl)2; G5: 2.5% NaOCl with ultrasonic activation; and G6: 2.5% Ca(OCl)2 with ultrasonic activation (US). Microbiological testing (colony-forming unit [CFU] counting) was performed to evaluate and show, respectively, the effectiveness of the proposed treatments. Data were subjected to 1-way analysis of variance followed by the post hoc Tukey test (α = 0.05). Groups 1 and 2 showed the highest mean contamination (3.26 log10 CFU/mL and 2.69 log10 CFU/mL, respectively), which was statistically different from all other groups (P < .05). Group 6 (Ca[OCl]2 + US) showed the lowest mean contamination (1.00 log10 CFU/mL), with no statistically significant difference found in groups 3 (NaOCl), 4 (Ca[OCl]2), and 5 (NaOCl + US) (P < .05). Ca(OCl)2 as well as passive ultrasonic irrigation can aid in chemomechanical preparation, contributing in a significant way to the reduction of microbial content during root canal treatment. Copyright © 2014 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Comparative antifungal efficacy of light-activated disinfection and octenidine hydrochloride with contemporary endodontic irrigants.

PubMed

Eldeniz, Ayce Unverdi; Guneser, Mehmet Burak; Akbulut, Makbule Bilge

2015-02-01

The aim of this study was to evaluate the antifungal effects of light-activated disinfection (LAD) in comparison with contemporary root canal irrigation solutions: sodium hypochlorite and 2% chlorhexidine gluconate and a new wound antiseptic, octenidine hydrochloride. Seventy extracted teeth having single root canals were contaminated with Candida albicans for 14 days. The samples were divided into five experimental (n = 10) and two control (positive and negative) groups (n = 10): (1) LAD with toluidine blue O, (2) octenidine hydrochloride (OCT), (3) 2.5% sodium hypochlorite (2.5% NaOCl), (4) 5.25% sodium hypochlorite (5.25% NaOCl) and (5) 2% chlorhexidine. Five millilitres of each test solution was applied for 3 min, and irradiation time used for LAD was 30 s. After treatment, the dentin chips were collected from inner canal walls into vials containing phosphate buffered saline, vortexed, serially diluted, seeded on Tryptic Soy Agar plates and incubated (37 °C, 48 h). The number of colony-forming units was then counted. Differences between LAD group and positive control group were statistically significant (P < 0.05). All Candida cells were totally eliminated in root canals irrigated with OCT, 2.5% NaOCl, 5.25% NaOCl and 2% chlorhexidine groups (CFU = 0). Within the limitations of this ex vivo study, LAD had minimal antimicrobial effect on C. albicans when used 30 s, and further modifications in LAD protocol are required to improve its antifungal capability. A new wound antiseptic, octenidine hydrochloride, demonstrated better potential than LAD in elimination of Candida albicans cells and may be a promising alternative to NaOCl and chlorhexidine solutions in future.

Bridging dry spells for maize cropping through supplemental irrigation in the Central Rift Valley of Ethiopia

NASA Astrophysics Data System (ADS)

Muluneh Bitew, Alemayehu; Keesstra, Saskia; Stroosnijder, Leo

2015-04-01

Maize yield in the Central Rift Valley of Ethiopia (CRV) suffers from dry spells at sensitive growth stages. Risk of crop failure makes farmers reluctant to invest in fertilizer. This makes the CRV food insecure. There are farms with well-maintained terraces and Rain Water Harvesting (RWH) systems using concrete farms ponds. We tested the hypothesis that in these farms supplemental irrigation with simultaneous crop intensification might boost production of a small maize area sufficient to improve food security. Intensification includes a higher plant density of a hybrid variety under optimum fertilization. First we assessed the probability of occurrence of dry spells. Then we estimated the availability of sufficient runoff in the ponds in dry years. During 2012 (dry) and 2013 (wet) on-farm field research was conducted with 10 combinations of supplemental irrigation and plant density. The simplest was rainfed farming with 30,000 plants ha-1. The most advanced was no water stress and 75,000 plants ha-1. Finally we compared our on-farm yield with that of neighbouring farmers. Because 2013 was a wet year no irrigation was needed. Our long term daily rainfall (1970-2011) analysis proves the occurrence of dry spells during the onset of the maize (Belg months March and April). In March there is hardly enough water in the ponds. So, we advise later sowing. Starting from April available water (runoff from a 2.2 ha catchment) matches crop water requirement (for 0.5 ha maize). Significant differences between grain and total biomass yield were observed between rainfed and other irrigation levels. However, since the largest difference is only 12%, the investment in irrigation non-critical drought years is not worth the effort. There was also a limited effect (18-22%) of increasing plant density. So, we advise not to use more than 45,000 plants ha-1. The grain yield and total biomass difference between farmers own practice and our on-farm research was 101% and 84% respectively in 2012. This large increase in grain yield is contributed to the higher use of (150% recommended) of fertilizer against the current use (50% or less) by adjacent farmers. Our hypothesis was that supplemental irrigation in combination with increased plant density would greatly increase grain yield. This hypothesis could not be proven with our 2 years experiment. Our experiment, once again, suggests that yield lower than attainable is not a matter of water shortage but rather an effect of lack of fertilizer.

Water management in Egypt for facing the future challenges

PubMed Central

Omar, Mohie El Din M.; Moussa, Ahmed M.A.

2016-01-01

The current water shortage in Egypt is 13.5 Billion cubic meter per year (BCM/yr) and is expected to continuously increase. Currently, this water shortage is compensated by drainage reuse which consequently deteriorates the water quality. Therefore, this research was commenced with the objective of assessing different scenarios for 2025 using the Water Evaluation and Planning (WEAP) model and by implementing different water sufficiency measures. Field data were assembled and analyzed, and different planning alternatives were proposed and tested in order to design three future scenarios. The findings indicated that water shortage in 2025 would be 26 BCM/yr in case of continuation of current policies. Planning alternatives were proposed to the irrigation canals, land irrigation timing, aquatic weeds in waterways and sugarcane areas in old agricultural lands. Other measures were suggested to pumping rates of deep groundwater, sprinkler and drip irrigation systems in new agricultural lands. Further measures were also suggested to automatic daily surveying for distribution leak and managing the pressure effectively in the domestic and industrial water distribution systems. Finally, extra measures for water supply were proposed including raising the permitted withdrawal limit from deep groundwater and the Nubian aquifer and developing the desalination resource. The proposed planning alternatives would completely eliminate the water shortage in 2025. PMID:27222745

Economic compensation standard for irrigation processes to safeguard environmental flows in the Yellow River Estuary, China

NASA Astrophysics Data System (ADS)

Pang, Aiping; Sun, Tao; Yang, Zhifeng

2013-03-01

SummaryAgriculture and ecosystems are increasingly competing for water. We propose an approach to assess the economic compensation standard required to release water from agricultural use to ecosystems while taking into account seasonal variability in river flow. First, we defined agricultural water shortage as the difference in water volume between agricultural demands and actual supply after maintaining environmental flows for ecosystems. Second, we developed a production loss model to establish the relationship between production losses and agricultural water shortages in view of seasonal variation in river discharge. Finally, we estimated the appropriate economic compensation for different irrigation stakeholders based on crop prices and production losses. A case study in the Yellow River Estuary, China, demonstrated that relatively stable economic compensation for irrigation processes can be defined based on the developed model, taking into account seasonal variations in river discharge and different levels of environmental flow. Annual economic compensation is not directly related to annual water shortage because of the temporal variability in river flow rate and environmental flow. Crops that have stable planting areas to guarantee food security should be selected as indicator crops in economic compensation assessments in the important grain production zone. Economic compensation may be implemented by creating funds to update water-saving measures in agricultural facilities.

Water management in Egypt for facing the future challenges.

PubMed

Omar, Mohie El Din M; Moussa, Ahmed M A

2016-05-01

The current water shortage in Egypt is 13.5 Billion cubic meter per year (BCM/yr) and is expected to continuously increase. Currently, this water shortage is compensated by drainage reuse which consequently deteriorates the water quality. Therefore, this research was commenced with the objective of assessing different scenarios for 2025 using the Water Evaluation and Planning (WEAP) model and by implementing different water sufficiency measures. Field data were assembled and analyzed, and different planning alternatives were proposed and tested in order to design three future scenarios. The findings indicated that water shortage in 2025 would be 26 BCM/yr in case of continuation of current policies. Planning alternatives were proposed to the irrigation canals, land irrigation timing, aquatic weeds in waterways and sugarcane areas in old agricultural lands. Other measures were suggested to pumping rates of deep groundwater, sprinkler and drip irrigation systems in new agricultural lands. Further measures were also suggested to automatic daily surveying for distribution leak and managing the pressure effectively in the domestic and industrial water distribution systems. Finally, extra measures for water supply were proposed including raising the permitted withdrawal limit from deep groundwater and the Nubian aquifer and developing the desalination resource. The proposed planning alternatives would completely eliminate the water shortage in 2025.

Security Services Discovery by ATM Endsystems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sholander, Peter; Tarman, Thomas

This contribution proposes strawman techniques for Security Service Discovery by ATM endsystems in ATM networks. Candidate techniques include ILMI extensions, ANS extensions and new ATM anycast addresses. Another option is a new protocol based on an IETF service discovery protocol, such as Service Location Protocol (SLP). Finally, this contribution provides strawman requirements for Security-Based Routing in ATM networks.

Effect of ultrasound streaming on the disinfection of flattened root canals prepared by rotary and reciprocating systems

PubMed Central

de Vasconcelos, Layla Reginna Silva Munhoz; Midena, Raquel Zanin; Minotti, Paloma Gagliardi; Pereira, Thais Cristina; Duarte, Marco Antonio Hungaro; de Andrade, Flaviana Bombarda

2017-01-01

Abstract New technical and scientific developments have been advocated to promote the success of the endodontic treatment. In addition to rotary and reciprocating systems, irrigating solution agitation has been suggested and passive ultrasonic irrigation (PUI) is the most used. Objective: To evaluate, in vitro, the effect of ultrasound streaming (US) in the disinfection of flattened root canal systems prepared by the ProTaper, BioRaCe and Reciproc systems, utilizing the microbiological culture. Methodology: Extracted human mandibular incisors (n=84) were used. Suspensions of Enterococcus faecalis (ATCC 29212) were standardized and inserted along with the teeth immersed in brain-heart infusion (BHI) broth. The contamination was made following a protocol during 5 days. The teeth were randomly divided into six groups: G1, ProTaper Universal; G2, ProTaper Universal with US; G3, BioRaCe; G4, BioRaCe with US; G5, Reciproc; and G6, Reciproc with US. Irrigation was performed with saline solution. After biomechanical preparation, microbiological samples were performed with sterilized paper points, which were diluted and spread on BHI agar; after 48 h, the colony forming units (CFU/mL) were counted for each sample. Results: Groups using ultrasonic agitation presented a greater antibacterial effect than the other ones, even using saline solution as irrigant. The ProTaper Universal system showed the best antibacterial activity of the tested systems (median of 0 CFU/mL with and without surfactant or ultrasonic activation [PUI]). Even with PUI, Reciproc (median of 2.5 CFU/mL with PUI and 5 without it) could not reduce as many colonies as ProTaper Universal without US. The BioRaCe system had greater bacterial reduction when using US (median of 0 CFU/mL with PUI and 30 without it). Conclusions: US promoted greater reduction in the number of bacteria in the flattened root canals prepared with nickel-titanium mechanized systems. Regarding the instruments used, the ProTaper Universal system was the most effective in reducing the bacterial number. PMID:29069144

Effect of ultrasound streaming on the disinfection of flattened root canals prepared by rotary and reciprocating systems.

PubMed

Vasconcelos, Layla Reginna Silva Munhoz de; Midena, Raquel Zanin; Minotti, Paloma Gagliardi; Pereira, Thais Cristina; Duarte, Marco Antonio Hungaro; Andrade, Flaviana Bombarda de

2017-01-01

New technical and scientific developments have been advocated to promote the success of the endodontic treatment. In addition to rotary and reciprocating systems, irrigating solution agitation has been suggested and passive ultrasonic irrigation (PUI) is the most used. To evaluate, in vitro, the effect of ultrasound streaming (US) in the disinfection of flattened root canal systems prepared by the ProTaper, BioRaCe and Reciproc systems, utilizing the microbiological culture. Extracted human mandibular incisors (n=84) were used. Suspensions of Enterococcus faecalis (ATCC 29212) were standardized and inserted along with the teeth immersed in brain-heart infusion (BHI) broth. The contamination was made following a protocol during 5 days. The teeth were randomly divided into six groups: G1, ProTaper Universal; G2, ProTaper Universal with US; G3, BioRaCe; G4, BioRaCe with US; G5, Reciproc; and G6, Reciproc with US. Irrigation was performed with saline solution. After biomechanical preparation, microbiological samples were performed with sterilized paper points, which were diluted and spread on BHI agar; after 48 h, the colony forming units (CFU/mL) were counted for each sample. Groups using ultrasonic agitation presented a greater antibacterial effect than the other ones, even using saline solution as irrigant. The ProTaper Universal system showed the best antibacterial activity of the tested systems (median of 0 CFU/mL with and without surfactant or ultrasonic activation [PUI]). Even with PUI, Reciproc (median of 2.5 CFU/mL with PUI and 5 without it) could not reduce as many colonies as ProTaper Universal without US. The BioRaCe system had greater bacterial reduction when using US (median of 0 CFU/mL with PUI and 30 without it). US promoted greater reduction in the number of bacteria in the flattened root canals prepared with nickel-titanium mechanized systems. Regarding the instruments used, the ProTaper Universal system was the most effective in reducing the bacterial number.

Impact of potential large-scale and medium-scale irrigation on the West African Monsoon and its dependence on location of irrigated area

NASA Astrophysics Data System (ADS)

Eltahir, E. A. B.; IM, E. S.

2014-12-01

This study investigates the impact of potential large-scale (about 400,000 km2) and medium-scale (about 60,000 km2) irrigation on the climate of West Africa using the MIT Regional Climate Model. A new irrigation module is implemented to assess the impact of location and scheduling of irrigation on rainfall distribution over West Africa. A control simulation (without irrigation) and various sensitivity experiments (with irrigation) are performed and compared to discern the effects of irrigation location, size and scheduling. In general, the irrigation-induced surface cooling due to anomalously wet soil tends to suppress moist convection and rainfall, which in turn induces local subsidence and low level anti-cyclonic circulation. These local effects are dominated by a consistent reduction of local rainfall over the irrigated land, irrespective of its location. However, the remote response of rainfall distribution to irrigation exhibits a significant sensitivity to the latitudinal position of irrigation. The low-level northeasterly flow associated with anti-cyclonic circulation centered over the irrigation area can enhance the extent of low level convergence through interaction with the prevailing monsoon flow, leading to significant increase in rainfall. Despite much reduced forcing of irrigation water, the medium-scale irrigation seems to draw the same response as large-scale irrigation, which supports the robustness of the response to irrigation in our modeling system. Both large-scale and medium-scale irrigation experiments show that an optimal irrigation location and scheduling exists that would lead to a more efficient use of irrigation water. The approach of using a regional climate model to investigate the impact of location and size of irrigation schemes may be the first step in incorporating land-atmosphere interactions in the design of location and size of irrigation projects. However, this theoretical approach is still in early stages of development and further research is needed before any practical application in water resources planning. Acknowledgements.This research was supported by the National Research Foundation Singapore through the Singapore MIT Alliance for Research and Technology's Center for Environmental Sensing and Modeling interdisciplinary research program.

Variable rate irrigation (VRI)

USDA-ARS?s Scientific Manuscript database

Variable rate irrigation (VRI) technology is now offered by all major manufacturers of moving irrigation systems, mostly on center pivot irrigation systems. Variable irrigation depths may be controlled by sector only, in which case only the speed of the irrigation lateral is regulated. Or, variable ...

Regional Scale Simulations of Nitrate Leaching through Agricultural Soils of California

NASA Astrophysics Data System (ADS)

Diamantopoulos, E.; Walkinshaw, M.; O'Geen, A. T.; Harter, T.

2016-12-01

Nitrate is recognized as one of California's most widespread groundwater contaminants. As opposed to point sources, which are relative easily identifiable sources of contamination, non-point sources of nitrate are diffuse and linked with widespread use of fertilizers in agricultural soils. California's agricultural regions have an incredible diversity of soils that encompass a huge range of properties. This complicates studies dealing with nitrate risk assessment, since important biological and physicochemical processes appear at the first meters of the vadose zone. The objective of this study is to evaluate all agricultural soils in California according to their potentiality for nitrate leaching based on numerical simulations using the Richards equation. We conducted simulations for 6000 unique soil profiles (over 22000 soil horizons) taking into account the effect of climate, crop type, irrigation and fertilization management scenarios. The final goal of this study is to evaluate simple management methods in terms of reduced nitrate leaching. We estimated drainage rates of water under the root zone and nitrate concentrations in the drain water at the regional scale. We present maps for all agricultural soils in California which can be used for risk assessment studies. Finally, our results indicate that adoption of simple irrigation and fertilization methods may significantly reduce nitrate leaching in vulnerable regions.

A field and statistical modeling study to estimate irrigation water use at Benchmark Farms study sites in southwestern Georgia, 1995-96

USGS Publications Warehouse

Fanning, Julia L.; Schwarz, Gregory E.; Lewis, William C.

2001-01-01

A benchmark irrigation monitoring network of farms located in a 32-county area in southwestern Georgia was established in 1995 to improve estimates of irrigation water use. A stratified random sample of 500 permitted irrigators was selected from a data base--maintained by the Georgia Department of Natural Resources, Georgia Environmental Protection Division, Water Resources Management Branch--to obtain 180 voluntary participants in the study area. Site-specific irrigation data were collected at each farm using running-time totalizers and noninvasive flowmeters. Data were collected and compiled for 50 farms for 1995 and 130 additional farms for the 1996 growing season--a total of 180 farms. Irrigation data collected during the 1996 growing season were compiled for 180 benchmark farms and used to develop a statistical model to estimate irrigation water use in 32 counties in southwestern Georgia. The estimates derived were developed from using a statistical approach know as "bootstrap analysis" that allows for the estimation of precision. Five model components--whether-to-irrigate, acres irrigated, crop selected, seasonal-irrigation scheduling, and the amount of irrigation applied--compose the irrigation model and were developed to reflect patterns in the data collected at Benchmark Farms Study area sites. The model estimated that peak irrigation for all counties in the study area occurred during July with significant irrigation also occurring during May, June, and August. Irwin and Tift were the most irrigated and Schley and Houston were the least irrigated counties in the study area. High irrigation intensity primarily was located along the eastern border of the study area; whereas, low irrigation intensity was located in the southwestern quadrant where ground water was the dominant irrigation source. Crop-level estimates showed sizable variations across crops and considerable uncertainty for all crops other than peanuts and pecans. Counties having the most irrigated acres showed higher variations in annual irrigation than counties having the least irrigated acres. The Benchmark Farms Study model estimates were higher than previous irrigation estimates, with 20 percent of the bias a result of underestimating irrigation acreage in earlier studies. Model estimates showed evidence of an upward bias of about 15 percent with the likely cause being a misrepresented inches-applied model. A better understanding of the causes of bias in the model could be determined with a larger irrigation sample size and increased substantially by automating the reporting of monthly totalizer amounts.

Irrigation trends in Kansas, 1991-2011

USGS Publications Warehouse

Kenny, Joan F.; Juracek, Kyle E.

2013-01-01

This fact sheet examines trends in total reported irrigation water use and acres irrigated as well as irrigation water use by crop type and system type in Kansas for the years 1991 through 2011. During the 21-year period, total reported irrigation water diversions varied substantially from year to year as affected primarily by climatic fluctuations. Total reported acres irrigated remained comparatively constant during this time, although acreages of irrigated corn increased and center pivots with drop nozzles became the dominant system type used for irrigation.

A comparative study of the debridement efficacy and apical extrusion of dynamic and passive root canal irrigation systems

PubMed Central

2014-01-01

Background Root canal irrigation carries a risk of extrusion of irrigant into the periapical tissues which can be associated with pain, swelling, and tissue damage. Studies have shown less extrusion with sonic or apical negative pressure devices compared with syringe and side-port needle or passive ultrasonic irrigation with continuous irrigant flow. This study aimed to evaluate the effectiveness of the EndoVac irrigation system, regarding 1) debris removal and 2) the control of apically extruded irrigating solution. Methods Fifty extracted human single-rooted teeth were used in this study. The teeth were then randomly divided into three experimental groups according to the type of irrigation used and one control group. In group 1, irrigation was performed using the EndoVac irrigation system. In group 2, irrigation was performed using a 30-gauge, tip-vented irrigation needle. In group 3, irrigation was performed using a 30-gauge, side-vented irrigation needle. The control group received instrumentation with no irrigation to serve as a control for cleaning efficiency. Root canal instrumentation was performed using the Profile NiTi rotary system with a crown-down technique. All of the experimental teeth were irrigated with the same amount of 5.25% sodium hypochlorite. The amount of extruded irrigating solution was then measured by subtracting the post-instrumentation weight from the pre-instrumentation weight using an electronic balance. The cleanliness of debris removal was evaluated using scanning electron microscopy. Results EndoVac irrigation had the least amount of extrusion followed by the side-vented and tip-vented method. The difference between the groups was statistically significant (P <0.01). As for the cleaning results, the debris collection in the EndoVac and tip-vented groups was the least in the apical third. In the control and the side-vented groups, the debris was the greatest in the apical third, but this difference was not significant among the three experimental groups. Conclusions The EndoVac irrigation system extruded significantly less irrigant solution than either needle irrigation system. Debris collection was the least in the apical third for the EndoVac irrigation system. No significant difference was found in the cleaning efficiency among the three irrigation systems. PMID:24512441

Heavy metal accumulation in soils and grains, and health risks associated with use of treated municipal wastewater in subsurface drip irrigation

NASA Astrophysics Data System (ADS)

Asgari, Kamran; Najafi, Payam; Cornelis, Wim M.

2014-05-01

Constant use of treated wastewater for irrigation over long periods may cause buildup of heavy metals up to toxic levels for plants, animals, and entails environmental hazards in different aspects. However, application of treated wastewater on agricultural land might be an effective and sustainable strategy in arid and semi-arid countries where fresh water resources are under great pressure, as long as potential harmful effects on the environment including soil, plants, and fresh water resources, and health risks to humans are minimized. The aim of this study was to assess the effect of using a deep emitter installation on lowering the potential heavy metal accumulation in soils and grains, and health risk under drip irrigation with treated municipal wastewater. A field experiment was conducted according to a split block design with two treatments (fresh and wastewater) and three sub treatments (0, 15 and 30 cm depth of emitters) in four replicates on a sandy loam soil, in Esfahan, Iran. The annual rainfall is about 123 mm, mean annual ETo is 1457 mm, and the elevation is 1590 m a.s.l.. A two-crop rotation of wheat [Triticum spp.] and corn [Zea mays]) was established on each plot with wheat growing from February to June and corn from July to September. Soil samples were collected before planting (initial value) and after harvesting (final value) for each crop in each year. Edible grain samples of corn and wheat were also collected. Elemental concentrations (Cu, Zn, Cd, Pb, Cr, Ni) in soil and grains were determined using an atomic absorption spectrophotometer. The concentrations of heavy metals in the wastewater-irrigated soils were not significantly different (P>0.05) compared with the freshwater-irrigated soils. The results showed no significant difference (P>0.05) of soil heavy metal content between different depths of emitters. A pollution load index PLI showed that there was not substantial buildup of heavy metals in the wastewater-irrigated soils compared to the freshwater-irrigated soils. Cu, Pb and Zn concentrations in wheat and corn grains were within permissible EPA limits, but concentrations of Cd (in wheat and corn) and Cr (in corn) were above the safe limits of EPA. In addition, concentrations of Ni in wheat and corn seeds were several folds higher than EPA standards. A health risk index (HRI) which is usually adopted to assess the health risk to hazard materials in foods showed values higher than 1 for Cd, particularly for wheat grain (HRI>2.5). Results also showed that intake of a Cu through consumption of edible wheat grains posed a relatively high potential health risk to children (HRI>1.4), whereas children might also be exposed to health risk from Cd and Cr from corn grains (HRI>1.4). Based on aforementioned results, it can be concluded that the of emitter depth in drip irrigation does not play a significant role in the accumulation of heavy metals from treated wastewater in our sandy loam soil. Although their accumulation in the soil was limited and similar to using fresh water, uptake of Cd and Cr by wheat and corn was relatively large hence resulting in health risk. The results suggest that more attention should be directed towards cultivation of other crops with drip irrigation system for a safe and more productive use of wastewater for irrigation. Alternatively, methods that filter the wastewater before it enters the soil environment might be an option that needs further investigation.

Tillage and Irrigation Management of Cotton in a Corn/Cotton Rotation

USDA-ARS?s Scientific Manuscript database

A research study was undertaken to evaluate the yield of cotton in a corn-cotton rotation under two tillage treatments, conventional and minimum/conservation, and two irrigation treatments, irrigated and non-irrigated. Crops were grown under four treatments, irrigated-conventional tillage, irrigate...

Peach response to water deficit in a semi-arid region

NASA Astrophysics Data System (ADS)

Paltineanu, C.; Septar, L.; Moale, C.; Nicolae, S.; Nicola, C.

2013-09-01

During three years a deficit irrigation experiment was performed on peach response under the semi-arid conditions of south-eastern Romania. Three sprinkler-irrigated treatments were investigated: fully irrigated, deficit irrigation treatment, and non-irrigated control treatment. Soil water content ranged between 60 and 76% of the plant available soil water capacity in fully irrigated, between 40 and 62% in deficit irrigation treatment, and between 30 and 45% in control. There were significant differences in fruit yield between the treatments. Irrigation water use efficiency was maximum in deficit irrigation treatment. Fruit yield correlated significantly with irrigation application. Total dry matter content, total solids content and titrable acidity of fruit were significantly different in the irrigated treatments vs. the control. Significant correlation coefficients were found between some fruit chemical components. For the possible future global warming conditions, when water use becomes increasingly restrictive, deficit irrigation will be a reasonable solution for water conservation in regions with similar soil and climate conditions.

Assessment of water sources to plant growth in rice based cropping systems by stable water isotopes

NASA Astrophysics Data System (ADS)

Mahindawansha, Amani; Kraft, Philipp; Racela, Heathcliff; Breuer, Lutz

2016-04-01

Rice is one of the most water-consuming crops in the world. Understanding water source utilization of rice will help us to improve water use efficiency (WUE) in paddy management. The objectives of our study are to evaluate the isotopic compositions of surface ponded water, soil water, irrigation water, groundwater, rain water and plant water and based on stable water isotope signatures to evaluate the contributions of various water sources to plant growth (wet rice, aerobic rice and maize) together with investigating the contribution of water from different soil horizons for plant growth in different maturity periods during wet and dry seasons. Finally we will compare the water balances and crop yields in both crops during both seasons and calculate the water use efficiencies. This will help to identify the most efficient water management systems in rice based cropping ecosystems using stable water isotopes. Soil samples are collected from 9 different depths at up to 60 cm in vegetative, reproductive and matured periods of plant growth together with stem samples. Soil and plant samples are extracted by cryogenic vacuum extraction. Root samples are collected up to 60 cm depth from 10 cm intercepts leading calculation of root length density and dry weight. Groundwater, surface water, rain water and irrigation water are sampled weekly. All water samples are analyzed for hydrogen and oxygen isotope ratios (d18O and dD) using Los Gatos Research DLT100. Rainfall records, ground water level, surface water level fluctuations and the amount of water irrigated in each field will be measured during the sampling period. The direct inference approach which is based on comparing isotopic compositions (dD and d18O) between plant stem water and soil water will be used to determine water sources taken up by plant. Multiple-source mass balance assessment can provide the estimated range of potential contributions of water from each soil depth to root water uptake of a crop. These evaluations will be used to determine the proportion of water from upper soil horizons and deep horizons for rice and maize in different maturity periods during wet and dry seasons. Finally we will estimate the influence of groundwater and surface water by irrigation water and/or by precipitation. First results of the sampling during the wet season 2015 will be presented.

Developing an evidence-based practice protocol: implications for midwifery practice.

PubMed

Carr, K C

2000-01-01

Evidence-based practice is defined and its importance to midwifery practice is presented. Guidelines are provided for the development of an evidence-based practice protocol. These include: identifying the clinical question, obtaining the evidence, evaluating the validity and importance of the evidence, synthesizing the evidence and applying it to the development of a protocol or clinical algorithm, and, finally, developing an evaluation plan or measurement strategy to see if the new protocol is effective.

Energy requirements in pressure irrigation systems

NASA Astrophysics Data System (ADS)

Sánchez, R.; Rodríguez-Sinobas, L.; Juana, L.; Laguna, F. V.; Castañón, G.; Gil, M.; Benítez, J.

2012-04-01

Modernization of irrigation schemes, generally understood as transformation of surface irrigation systems into pressure -sprinkler and trickle- irrigation systems, aims at, among others, improving irrigation efficiency and reduction of operation and maintenance efforts made by the irrigators. However, pressure irrigation systems, in contrast, carry a serious energy cost. Energy requirements depend on decisions taken on management strategies during the operation phase, which are conditioned by previous decisions taken on the design project of the different elements which compose the irrigation system. Most of the countries where irrigation activity is significant bear in mind that modernization irrigation must play a key role in the agricultural infrastructure policies. The objective of this study is to characterize and estimate the mean and variation of the energy consumed by common types of irrigation systems and their management possibilities. The work includes all processes involved from the diversion of water into irrigation specific infrastructure to water discharge by the emitters installed on the crop fields. Simulation taking into account all elements comprising the irrigation system has been used to estimate the energy requirements of typical irrigation systems of several crop production systems. It has been applied to extensive and intensive crop systems, such us extensive winter crops, summer crops and olive trees, fruit trees and vineyards and intensive horticulture in greenhouses. The simulation of various types of irrigation systems and management strategies, in the framework imposed by particular cropping systems, would help to develop criteria for improving the energy balance in relation to the irrigation water supply productivity.

Improvement of "Novel Multiparty Quantum Key Agreement Protocol with GHZ States"

NASA Astrophysics Data System (ADS)

Gu, Jun; Hwang, Tzonelih

2017-10-01

Quantum key agreement (QKA) protocol is a method for negotiating a fair and secure key among mutually untrusted participants. Recently, Xu et al. (Quantum Inf. Process. 13:2587-2594, 2014) proposed a multi-party QKA protocol based on Greenberger-Horne-Zeilinger (GHZ) states. However, this study points out that Xu et al.'s protocol cannot provide the fairness property. That is, the last involved participant in the protocol can manipulate the final shared secret key without being detected by the other participants. Moreover, according to Yu et al.'s research (2015), Xu et al.'s protocol cannot avoid the public discussion attack too. To avoid these weaknesses, an improved QKA protocol is proposed.

An evaluation of time-series MODIS 250-meter vegetation index data for crop mapping in the United States Central Great Plains

NASA Astrophysics Data System (ADS)

Wardlow, Brian Douglas

The objectives of this research were to: (1) investigate time-series MODIS (Moderate Resolution Imaging Spectroradiometer) 250-meter EVI (Enhanced Vegetation Index) and NDVI (Normalized Difference Vegetation Index) data for regional-scale crop-related land use/land cover characterization in the U.S. Central Great Plains and (2) develop and test a MODIS-based crop mapping protocol. A pixel-level analysis of the time-series MODIS 250-m VIs for 2,000+ field sites across Kansas found that unique spectral-temporal signatures were detected for the region's major crop types, consistent with the crops' phenology. Intra-class variations were detected in VI data associated with different land use practices, climatic conditions, and planting dates for the crops. The VIs depicted similar seasonal variations and were highly correlated. A pilot study in southwest Kansas found that accurate and detailed cropping patterns could be mapped using the MODIS 250-m VI data. Overall and class-specific accuracies were generally greater than 90% for mapping crop/non-crop, general crops (alfalfa, summer crops, winter wheat, and fallow), summer crops (corn, sorghum, and soybeans), and irrigated/non-irrigated crops using either VI dataset. The classified crop areas also had a high level of agreement (<5% difference) with the USDA reported crop areas. Both VIs produced comparable crop maps with only a 1-2% difference between their classification accuracies and a high level of pixel-level agreement (>90%) between their classified crop patterns. This hierarchical crop mapping protocol was tested for Kansas and produced similar classification results over a larger and more diverse area. Overall and class-specific accuracies were typically between 85% and 95% for the crop maps. At the state level, the maps had a high level of areal agreement (<5% difference) with the USDA crop area figures and their classified patterns were consistent with the state's cropping practices. In general, the protocol's performance was relatively consistent across the state's range of environmental conditions, landscape patterns, and cropping practices. The largest areal differences occurred in eastern Kansas due to the omission of many small cropland areas that were not resolvable at MODIS' 250-m resolution. Notable regional deviations in classified areas also occurred for selected classes due to localized precipitation patterns and specific cropping practices.

Optimizing preplant irrigation for maize under limited water in the high plains

USDA-ARS?s Scientific Manuscript database

Due to inadequate irrigation capacity, some farmers in the United States High Plains apply preplant irrigation to buffer the crop between irrigation events during the cropping season. The purpose of the study was to determine preplant irrigation amount and irrigation capacity combinations that optim...

Comparative study of heavy metals in "soil-wheat" systems between sewage-irrigated areas and clean-water-irrigated areas in suburban Beijing.

PubMed

Zhao, Ye; Han, Sha-Sha; Chen, Zhi-Fan; Liu, Jing; Hu, Honq-Xia

2015-01-01

After years of irrigating farmland with wastewater, concern is increasing about health risks from heavy metals contaminating wheat grown in sewage-irrigated soils in suburban areas of Beijing, China. The study discussed in this article aimed to compare the characteristics of heavy metal distribution in a sewage-irrigated "soil-wheat" system with those from a clean-water-irrigated area by collecting and analyzing samples from both areas. The results indicated that the average concentrations of copper, chromium, lead, and zinc in sewage-irrigated soil were higher than the values in the clean-water-irrigated region. Irrigation with wastewater could lead to increased bioconcentration factors. Therefore, issues of food contamination caused by sewage irrigation deserve more attention.

Effects of irrigation practices on water use in the groundwater management districts within the Kansas high plains, 1991-2003

USGS Publications Warehouse

Perry, Charles A.

2006-01-01

Data compiled for the High Plains region of Kansas that includes five Groundwater Management Districts (GMDs) were analyzed for trends in irrigation water use, acres irrigated, precipitation, irrigation system types, and irrigated crop types to determine the effects of irrigation practices on water use over time. For the study period 1991 through 2003, precipitation decreased significantly (with 95-percent confidence) in northwestern and west-central Kansas but not in the southwestern and south-central parts of the State. Irrigation water use had no statistically significant trend during this period. There was a good (R= -0.77) relation between average regional precipitation and total GMD irrigation water use. When irrigation water use was adjusted for this relation, there was a positive trend (90-percent confidence level) in the adjusted irrigation water use. Another adjustment to water use was made using the ratio of annual precipitation to 1991-2005 average precipitation, which resulted in a negative trend (95-percent confidence level) in irrigation water use. This demonstrated the contradictory nature of precipitation adjustments to water use, making their utility somewhat suspect. GMD 3 in southwestern Kansas used 63 percent of the total acre-feet of irrigation water within all the GMDs. When all GMDs are considered, the number of irrigated acres for flood and center pivot systems without drop nozzles decreased significantly during the study period. At the same time the number of drop nozzle irrigated acres increased significantly. The number of irrigated acres of water-intensive crops (corn, alfalfa, and soybeans) also increased significantly, whereas the number of less- or non-water-intensive crops (grain sorghum and wheat), and multiple crop type acres decreased. Drop nozzle irrigation systems used approximately 2 percent less water in a year-by-year comparison than center pivot systems and 8 to 11 percent less water than flood irrigation. The best estimator of irrigation water use incorporated total acres irrigated and annual average or March-October regional precipitation. A conclusion that can be drawn from the trend analyses described in this report is that, although irrigation water use for all GMDs showed no statistically significant trend, an apparent increased efficiency of center pivots irrigation systems with drop nozzles has allowed more water-intensive crops to be grown on more irrigated acres.

Multi-party Quantum Key Agreement without Entanglement

NASA Astrophysics Data System (ADS)

Cai, Bin-Bin; Guo, Gong-De; Lin, Song

2017-04-01

A new efficient quantum key agreement protocol without entanglement is proposed. In this protocol, each user encodes his secret key into the traveling particles by performing one of four rotation operations that one cannot perfectly distinguish. In the end, all users can simultaneously obtain the final shared key. The security of the presented protocol against some common attacks is discussed. It is shown that this protocol can effectively protect the privacy of each user and satisfy the requirement of fairness in theory. Moreover, the quantum carriers and the encoding operations used in the protocol can be achieved in realistic physical devices. Therefore, the presented protocol is feasible with current technology.

Spectrophotometric determination of irrigant extrusion using passive ultrasonic irrigation, EndoActivator, or syringe irrigation.

PubMed

Rodríguez-Figueroa, Carolina; McClanahan, Scott B; Bowles, Walter R

2014-10-01

Sodium hypochlorite (NaOCl) irrigation is critical to endodontic success, and several new methods have been developed to improve irrigation efficacy (eg, passive ultrasonic irrigation [PUI] and EndoActivator [EA]). Using a novel spectrophotometric method, this study evaluated NaOCl irrigant extrusion during canal irrigation. One hundred fourteen single-rooted extracted teeth were decoronated to leave 15 mm of the root length for each tooth. Cleaning and shaping of the teeth were completed using standardized hand and rotary instrumentation to an apical file size #40/0.04 taper. Roots were sealed (not apex), and 54 straight roots (n = 18/group) and 60 curved roots (>20° curvature, n = 20/group) were included. Teeth were irrigated with 5.25% NaOCl by 1 of 3 methods: passive irrigation with needle, PUI, or EA irrigation. Extrusion of NaOCl was evaluated using a pH indicator and a spectrophotometer. Standard curves were prepared with known amounts of irrigant to quantify amounts in unknown samples. Irrigant extrusion was minimal with all methods, with most teeth showing no NaOCl extrusion in straight or curved roots. Minor NaOCl extrusion (1-3 μL) in straight roots or curved roots occurred in 10%-11% of teeth in all 3 irrigant methods. Two teeth in both the syringe irrigation and the EA group extruded 3-10 μL of NaOCl. The spectrophotometric method used in this study proved to be very sensitive while providing quantification of the irrigant levels extruded. Using the PUI or EA tip to within 1 mm of the working length appears to be fairly safe, but apical anatomy can vary in teeth to allow extrusion of irrigant. Copyright © 2014 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

A case study of field-scale maize irrigation patterns in western Nebraska: implications for water managers and recommendations for hyper-resolution land surface modeling

NASA Astrophysics Data System (ADS)

Gibson, Justin; Franz, Trenton E.; Wang, Tiejun; Gates, John; Grassini, Patricio; Yang, Haishun; Eisenhauer, Dean

2017-02-01

In many agricultural regions, the human use of water for irrigation is often ignored or poorly represented in land surface models (LSMs) and operational forecasts. Because irrigation increases soil moisture, feedback on the surface energy balance, rainfall recycling, and atmospheric dynamics is not represented and may lead to reduced model skill. In this work, we describe four plausible and relatively simple irrigation routines that can be coupled to the next generation of hyper-resolution LSMs operating at scales of 1 km or less. The irrigation output from the four routines (crop model, precipitation delayed, evapotranspiration replacement, and vadose zone model) is compared against a historical field-scale irrigation database (2008-2014) from a 35 km2 study area under maize production and center pivot irrigation in western Nebraska (USA). We find that the most yield-conservative irrigation routine (crop model) produces seasonal totals of irrigation that compare well against the observed irrigation amounts across a range of wet and dry years but with a low bias of 80 mm yr-1. The most aggressive irrigation saving routine (vadose zone model) indicates a potential irrigation savings of 120 mm yr-1 and yield losses of less than 3 % against the crop model benchmark and historical averages. The results of the various irrigation routines and associated yield penalties will be valuable for future consideration by local water managers to be informed about the potential value of irrigation saving technologies and irrigation practices. Moreover, the routines offer the hyper-resolution LSM community a range of irrigation routines to better constrain irrigation decision-making at critical temporal (daily) and spatial scales (< 1 km).

Developing and validating trace fear conditioning protocols in C57BL/6 mice.

PubMed

Burman, Michael A; Simmons, Cassandra A; Hughes, Miles; Lei, Lei

2014-01-30

Classical fear conditioning is commonly used to study the biology of fear, anxiety and memory. Previous research demonstrated that delay conditioning requires a neural circuit involving the amygdala, but not usually the hippocampus. Trace and contextual fear conditioning require the amygdala and hippocampus. While these paradigms were developed primarily using rat models, they are increasingly being used in mice. The current studies develop trace fear conditioning and control paradigms to allow for the assessment of trace and delay fear conditioning in C57BL/6N mice. Our initial protocol yielded clear delay and contextual conditioning. However, trace conditioning failed to differentiate from an unpaired group and was not hippocampus-dependent. These results suggested that the protocol needed to be modified to specifically accommodate trace conditioning the mice. In order to reduce unconditioned freezing and increase learning, the final protocol was developed by decreasing the intensity of the tone and by increasing the inter-trial interval. Our final protocol produced trace conditioned freezing that was significantly greater than that followed unpaired stimulus exposure and was disrupted by hippocampus lesions. A review of the literature produced 90 articles using trace conditioning in mice. Few of those articles used any kind of behavioral control group, which is required to rule out non-associative factors causing fearful behavior. Fewer used unpaired groups involving tones and shocks within a session, which is the optimal control group. Our final trace conditioning protocol can be used in future studies examining genetically modified C57BL/6N mice. Copyright © 2013 Elsevier B.V. All rights reserved.

Developing and Validating Trace Fear Conditioning Protocols in C57BL/6 Mice

PubMed Central

Burman, Michael A; Simmons, Cassandra A; Hughes, Miles; Lei, Lei

2013-01-01

Background Classical fear conditioning is commonly used to study the biology of fear, anxiety and memory. Previous research demonstrated that delay conditioning requires a neural circuit involving the amygdala, but not usually the hippocampus. Trace and contextual fear conditioning require the amygdala and hippocampus. While these paradigms were developed primarily using rat models, they are increasingly being used in mice. New Method The current studies develop trace fear conditioning and control paradigms to allow for the assessment of trace and delay fear conditioning in C57BL/6N mice. Our initial protocol yielded clear delay and contextual conditioning. However, trace conditioning failed to differentiate from an unpaired group and was not hippocampus-dependent. These results suggested that the protocol needed to be modified to specifically accommodate trace conditioning the mice. In order to reduce unconditioned freezing and increase learning, the final protocol was developed by decreasing the intensity of the tone and by increasing the inter-trial interval. Results Our final protocol produced trace conditioned freezing that was significantly greater than that followed unpaired stimulus exposure and was disrupted by hippocampus lesions. Comparison with Existing Methods A review of the literature produced 90 articles using trace conditioning in mice. Few of those articles used any kind of behavioral control group, which is required to rule out non-associative factors causing fearful behavior. Fewer used unpaired groups involving tones and shocks within a session, which is the optimal control group. Conclusions Our final trace conditioning protocol can be used in future studies examining genetically modified C57BL/6N mice. PMID:24269252

Determinants of farmers' participation in collective maintenance of irrigation infrastructure in KwaZulu-Natal

NASA Astrophysics Data System (ADS)

Sharaunga, S.; Mudhara, M.

2018-06-01

The decentralization framework and the Dublin Principles on Integrated Water Resource Management (IWRM) emphasize the need for a participatory approach to irrigation water management. This study identifies the factors influencing farmers' decision to, and extent of participation in the maintenance of irrigation infrastructure in KwaZulu-Natal province, South Africa based on cross-section data collected from 320 randomly selected smallholder irrigating farmers. A two-step Heckman regression model was applied in the analysis. It was established that households whose heads were older, block committee members, with larger irrigation plots, good soil quality and experiencing severe irrigation water shortages are more likely to participate in maintenance of irrigation infrastructure. On the other hand, farmers with insecure land tenure and with no access to irrigation water were less likely to make the decision to participate. Farmers who were members of the farming cooperative as well as block committee members and those paying irrigation water costs were likely to intensively participate in maintaining irrigation infrastructure. Therefore, decentralization alone cannot lead to improved irrigation outcomes. Several factors are necessary for households to participate intensively in the maintenance of irrigation infrastructure. Governments should address these challenges before handing irrigation schemes to their beneficiaries.

Quantification and Multi-purpose Allocation of Water Resources in a Dual-reservoir System

NASA Astrophysics Data System (ADS)

Salami, Y. D.

2017-12-01

Transboundary rivers that run through separate water management jurisdictions sometimes experience competitive water usage. Where the river has multiple existing or planned dams along its course, quantification and efficient allocation of water for such purposes as hydropower generation, irrigation for agriculture, and water supply can be a challenge. This problem is even more pronounced when large parts of the river basin are located in semi-arid regions known for water insecurity, poor crop yields from irrigation scheme failures, and human population displacement arising from water-related conflict. This study seeks to mitigate the impacts of such factors on the Kainji-Jebba dual-reservoir system located along the Niger River in Africa by seasonally quantifying and efficiently apportioning water to all stipulated uses of both dams thereby improving operational policy and long-term water security. Historical storage fluctuations (18 km3 to 5 km3) and flows into and out of both reservoirs were analyzed for relationships to such things as surrounding catchment contribution, dam operational policies, irrigation and hydropower requirements, etc. Optimum values of the aforementioned parameters were then determined by simulations based upon hydrological contributions and withdrawals and worst case scenarios of natural and anthropogenic conditions (like annual probability of reservoir depletion) affecting water availability and allocation. Finally, quantification and optimized allocation of water was done based on needs for hydropower, irrigation for agriculture, water supply, and storage evacuation for flood control. Results revealed that water supply potential increased by 69%, average agricultural yield improved by 36%, and hydropower generation increased by 54% and 66% at the upstream and downstream dams respectively. Lessons learned from this study may help provide a robust and practical means of water resources management in similar river basins and multi-reservoir systems.

Supplement Analysis for the Watershed Management Program EIS (DOE/EIS-0265/SA-106) - Water Entity (Trout Unlimited Montana Water Project 2003)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yarde, Richard

2003-06-13

BPA proposes to fund several water rights acquisition projects proposed by Trout Unlimited Montana Water Project (TU). The funding will be administered by the National Fish and Wildlife Foundation, the entity administering the Columbia Basin Water Transactions Program, initiated under RPA 151 of the National Marine Fisheries Service’s 2000 Biological Opinion on the Operation of the Federal Columbia River Power System. The water rights acquired by TU will be left instream to increase flow and improve water quality. Increasing instream flow of water-limited streams benefits fish listed under the Endangered Species Act. The three projects proposed by TU include: amore » Diversion Reduction Agreement, where the landowner agrees to leave up to 4 cubic feet per second (cfs) of water in Rock Creek for the 2003 irrigation season; another Diversion Reduction Agreement for the latter part of the 2003 irrigation season, under which the landowner would agree to cease diverting 1.65 cfs on Rock Creek and between 3 to 6 cfs from the North Fork Blackfoot River; the final proposal is one piece of a larger project in conjunction with other local, federal and state entities, to install a pipeline and sprinkler system to replace a ditch and flood irrigation system, which will result in the conversion of 15.11 cfs of water rights to instream flow. TU's contribution to the proposal (and BPA’s funding) is limited to working with the landowner to convert the water rights to instream flow; all other components of the project, including the irrigation efficiency work, is being done in conjunction with other federal agencies with independent NEPA and other environmental review and consultation obligations.« less

Crop identification for the delineation of irrigated regions under scarce data conditions: a new approach based on chaos theory

NASA Astrophysics Data System (ADS)

Mangiarotti, S.; Muddu, S.; Sharma, A. K.; Corgne, S.; Ruiz, L.; Hubert-Moy, L.

2015-12-01

Groundwater is one of the main water reservoirs used for irrigation in regions of scarce water resources. For this reason, crop irrigation is expected to have a direct influence on this reservoir. To understand the time evolution of the groundwater table and its storage changes, it is important to delineate irrigated crops, whose evaporative demand is relatively higher. Such delineation may be performed based on classical classification approaches using optical remote sensing. However, it remains a difficult problem in regions where plots do not exceed a few hectares and exhibit a very heterogeneous pattern with multiple crops. This difficulty is emphasized in South India where two or three months of cloudy conditions during the monsoon period can hide crop growth during the year. An alternative approach is introduced here that takes advantage of such scarce signal. Ten different crops are considered in the present study. A bank of crop models is first established based on the global modeling technique [1]. These models are then tested using original time series (from which models were obtained) in order to evaluate the information that can be deduced from these models in an inverse approach. The approach is then tested on an independent data set and is finally applied to a large ensemble of 10,000 time series of plot data extracted from the Berambadi catchment (AMBHAS site) part of the Kabini River basin CZO, South India. Results show that despite the important two-month gap in satellite observations in the visible band, interpolated vegetation index remains an interesting indicator for identification of crops in South India. [1] S. Mangiarotti, R. Coudret, L. Drapeau, & L. Jarlan, Polynomial search and global modeling: Two algorithms for modeling chaos, Phys. Rev. E, 86(4), 046205 (2012).

Qualitative analysis of precipitate formation on the surface and in the tubules of dentin irrigated with sodium hypochlorite and a final rinse of chlorhexidine or QMiX.

PubMed

Kolosowski, Kamil P; Sodhi, Rana N S; Kishen, Anil; Basrani, Bettina R

2014-12-01

Interaction of sodium hypochlorite (NaOCl) mixed with chlorhexidine (CHX) produces a brown precipitate containing para-chloroaniline (PCA). When QMiX is mixed with NaOCl, no precipitate forms, but color change occurs. The aim of this study was to qualitatively assess the formation of precipitate and PCA on the surface and in the tubules of dentin irrigated with NaOCl, followed either by EDTA, NaOCl, and CHX or by saline and QMiX by using time-of-flight secondary ion mass spectrometry (TOF-SIMS). Dentin blocks were obtained from human maxillary molars, embedded in resin, and cross-sectioned to expose dentin. Specimens in group 1 were immersed in 2.5% NaOCl, followed by 17% EDTA, 2.5% NaOCl, and 2% CHX. Specimens in group 2 were immersed in 2.5% NaOCl, followed by saline and QMiX. The dentin surfaces were subjected to TOF-SIMS spectra analysis. Longitudinal sections of dentin blocks were then exposed and subjected to TOF-SIMS analysis. All samples and analysis were performed in triplicate for confirmation. TOF-SIMS analysis of group 1 revealed an irregular precipitate, containing PCA and CHX breakdown products, on the dentin surfaces, occluding and extending into the tubules. In TOF-SIMS analysis of group 2, no precipitates, including PCA, were detected on the dentin surface or in the tubules. Within the limitations of this study, precipitate containing PCA was formed in the tubules of dentin irrigated with NaOCl followed by CHX. No precipitates or PCA were detected in the tubules of dentin irrigated with NaOCl followed by saline and QMiX. Copyright © 2014 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Estimating riparian and agricultural evapotranspiration by reference crop evapotranspiration and MODIS Enhanced Vegetation Index

USGS Publications Warehouse

Nagler, Pamela L.; Glenn, Edward P.; Nguyen, Uyen; Scott, Russell; Doody, Tania

2013-01-01

Dryland river basins frequently support both irrigated agriculture and riparian vegetation and remote sensing methods are needed to monitor water use by both crops and natural vegetation in irrigation districts. We developed an algorithm for estimating actual evapotranspiration (ETa) based on the Enhanced Vegetation Index (EVI) from the Moderate Resolution Imaging Spectrometer (MODIS) sensor on the EOS-1 Terra satellite and locally-derived measurements of reference crop ET (ETo). The algorithm was calibrated with five years of ETa data from three eddy covariance flux towers set in riparian plant associations on the upper San Pedro River, Arizona, supplemented with ETa data for alfalfa and cotton from the literature. The algorithm was based on an equation of the form ETa = ETo [a(1 − e−bEVI) − c], where the term (1 − e−bEVI) is derived from the Beer-Lambert Law to express light absorption by a canopy, with EVI replacing leaf area index as an estimate of the density of light-absorbing units. The resulting algorithm capably predicted ETa across riparian plants and crops (r2 = 0.73). It was then tested against water balance data for five irrigation districts and flux tower data for two riparian zones for which season-long or multi-year ETa data were available. Predictions were within 10% of measured results in each case, with a non-significant (P = 0.89) difference between mean measured and modeled ETa of 5.4% over all validation sites. Validation and calibration data sets were combined to present a final predictive equation for application across crops and riparian plant associations for monitoring individual irrigation districts or for conducting global water use assessments of mixed agricultural and riparian biomes.

Impact of needle insertion depth on the removal of hard-tissue debris.

PubMed

Perez, R; Neves, A A; Belladonna, F G; Silva, E J N L; Souza, E M; Fidel, S; Versiani, M A; Lima, I; Carvalho, C; De-Deus, G

2017-06-01

To evaluate the effect of depth of insertion of an irrigation needle tip on the removal of hard-tissue debris using micro-computed tomographic (micro-CT) imaging. Twenty isthmus-containing mesial roots of mandibular molars were anatomically matched based on similar morphological dimensions using micro-CT evaluation and assigned to two groups (n = 10), according to the depth of the irrigation needle tip during biomechanical preparation: 1 or 5 mm short of the working length (WL). The preparation was performed with Reciproc R25 file (tip size 25, .08 taper) and 5.25% NaOCl as irrigant. The final rinse was 17% EDTA followed by bidistilled water. Then, specimens were scanned again, and the matched images of the canals, before and after preparation, were examined to quantify the amount of hard-tissue debris, expressed as the percentage volume of the initial root canal volume. Data were compared statistically using the Mann-Whitney U-test. None of the tested needle insertion depths yielded root canals completely free from hard-tissue debris. The insertion depth exerted a significant influence on debris removal, with a significant reduction in the percentage volume of hard-tissue debris when the needle was inserted 1 mm short of the WL (P < 0.05). The insertion depth of irrigation needles significantly influenced the removal of hard-tissue debris. A needle tip positioned 1 mm short of the WL resulted in percentage levels of hard-tissue debris removal almost three times higher than when positioned 5 mm from the WL. © 2016 International Endodontic Journal. Published by John Wiley & Sons Ltd.

Modern Endodontic Principles Part 4: Irrigation.

PubMed

Darcey, James; Jawad, Sarra; Taylor, Carly; Roudsari, Reza Vahid; Hunter, Mark

2016-01-01

The complex anatomy of the tooth limits the ability to eradicate pathogens by mechanical means alone. Irrigation is the key to solving this problem. This paper highlights the importance of irrigation, the key irrigants available and methods of improving the performance of irrigants within the canal. CPD/CLINICAL RELEVANCE: To provide advice on which irrigants to use, how to use them effectively and safely and what to do if irrigants are extruded beyond the apex.

Optimal control solutions to sodic soil reclamation

NASA Astrophysics Data System (ADS)

Mau, Yair; Porporato, Amilcare

2016-05-01

We study the reclamation process of a sodic soil by irrigation with water amended with calcium cations. In order to explore the entire range of time-dependent strategies, this task is framed as an optimal control problem, where the amendment rate is the control and the total rehabilitation time is the quantity to be minimized. We use a minimalist model of vertically averaged soil salinity and sodicity, in which the main feedback controlling the dynamics is the nonlinear coupling of soil water and exchange complex, given by the Gapon equation. We show that the optimal solution is a bang-bang control strategy, where the amendment rate is discontinuously switched along the process from a maximum value to zero. The solution enables a reduction in remediation time of about 50%, compared with the continuous use of good-quality irrigation water. Because of its general structure, the bang-bang solution is also shown to work for the reclamation of other soil conditions, such as saline-sodic soils. The novelty in our modeling approach is the capability of searching the entire "strategy space" for optimal time-dependent protocols. The optimal solutions found for the minimalist model can be then fine-tuned by experiments and numerical simulations, applicable to realistic conditions that include spatial variability and heterogeneities.

Cotton irrigation timing with variable seasonal irrigation capacities in the Texas south plains.

USDA-ARS?s Scientific Manuscript database

Within the Ogallala Aquifer Region of Texas, the irrigation capacity (IC) for a given field often changes within a growing season due to seasonal depletion of the aquifer, in season changes in crop irrigation needs in dry years, or consequences of irrigation volume limits imposed by irrigation distr...

Soil and Nutrient Losses from Small Sprinkler and Furrow Irrigated Watersheds in Southern Idaho

USDA-ARS?s Scientific Manuscript database

Sediment and associated nutrients flowing to the Snake River with furrow irrigation runoff and unused irrigation water have been a concern in the Twin Falls irrigation tract in southern Idaho. Converting furrow irrigated fields to sprinkler irrigation is one practice that has been promoted, and rece...

Matching soil salinization and cropping systems in communally managed irrigation schemes

NASA Astrophysics Data System (ADS)

Malota, Mphatso; Mchenga, Joshua

2018-03-01

Occurrence of soil salinization in irrigation schemes can be a good indicator to introduce high salt tolerant crops in irrigation schemes. This study assessed the level of soil salinization in a communally managed 233 ha Nkhate irrigation scheme in the Lower Shire Valley region of Malawi. Soil samples were collected within the 0-0.4 m soil depth from eight randomly selected irrigation blocks. Irrigation water samples were also collected from five randomly selected locations along the Nkhate River which supplies irrigation water to the scheme. Salinity of both the soil and the irrigation water samples was determined using an electrical conductivity (EC) meter. Analysis of the results indicated that even for very low salinity tolerant crops (ECi < 2 dS/m), the irrigation water was suitable for irrigation purposes. However, root-zone soil salinity profiles depicted that leaching of salts was not adequate and that the leaching requirement for the scheme needs to be relooked and always be adhered to during irrigation operation. The study concluded that the crop system at the scheme needs to be adjusted to match with prevailing soil and irrigation water salinity levels.

HINTS Puerto Rico: Final Report

Cancer.gov

This final report describes HINTS implementation in Puerto Rico. The report addresses sampling; staffing, training and management of data collection; calling protocol; findings from the CATI Operations, and sample weights.

Irrigation of steppe soils in the south of Russia: Problems and solutions (Analysis of Irrigation Practices in 1950-1990)

NASA Astrophysics Data System (ADS)

Minashina, N. G.

2009-07-01

Experience in irrigation of chernozems in the steppe zone of Russia for a period from 1950 to 1990 is analyzed. By the end of this period and in the subsequent years, the areas under irrigation reduced considerably, and the soil productivity worsened. This was caused by the improper design of irrigation systems, on the one hand, and by the low tolerance of chernozems toward increased moistening upon irrigation, on the other hand. The analysis of the factors and regimes of soil formation under irrigation conditions shows that irrigation-induced changes in the soil hydrology also lead to changes in the soil physicochemical, biochemical, and other properties. In particular, changes in the composition of exchangeable cations lead to the development of solonetzic process. In many areas, irrigation of chernozems was accompanied by the appearance of solonetzic, vertic, saline, and eroded soils. The development of soil degradation processes is described. In general, the deterioration of irrigated chernozems was related to the absence of adequate experience in irrigation of steppe soils, unskilled personnel, improper regime of irrigation, and excessively high rates of watering. In some cases, the poor quality of irrigation water resulted in the development of soil salinization and alkalization. To improve the situation, the training of personnel is necessary; the strategy of continuous irrigation should be replaced by the strategy of supplementary irrigation in the critical periods of crop development.

Identifying Spatiotemporal Changes In Irrigated Area Across Southwestern Michigan, USA, Using Remote Sensing and Climate Data

NASA Astrophysics Data System (ADS)

Xu, T.; Deines, J. M.; Kendall, A. D.; Hyndman, D. W.

2017-12-01

Irrigation, which has become more common in humid regions, is the largest consumptive water use across the US and the globe. In southwestern Michigan, there has been a dramatic expansion in irrigation water use for row crops (primarily corn and soybean) in the past decade, mostly from groundwater pumping. The rapid expansion of irrigated row crops has potentially profound implications for terrestrial water balances, food production, and local to regional climate. Detailed maps of spatio-temporal changes in irrigation are essential to better understand irrigation impacts. However, accurate monitoring of irrigation area can be difficult in humid regions using remotely sensed methods due to the similarity in greenness between non-irrigated and irrigated areas in most years. Here, we use remote sensing to create annual, 30m-resolution maps of irrigated cropland by integrating Landsat and MODIS satellite products along with the PRISM climate dataset. From these data we developed spatial time series of vegetation and extreme weather indices, including novel indices we developed specifically to maximize detection of irrigation. Using these input data, machine learning classification was then performed over the region to identify irrigated crop area for each year. The resulting annual irrigation maps suggest that total irrigated area in southwestern Michigan increased by 160% from 2000 to 2017. The accuracy of the maps is assessed relative to maps created for an arid region using the same method. The maps can be integrated into hydrologic models to quantify irrigation impacts and support water resources management.

A modeling study of irrigation effects on global surface water and groundwater resources under a changing climate

DOE Office of Scientific and Technical Information (OSTI.GOV)

Leng, Guoyong; Huang, Maoyi; Tang, Qiuhong

In this paper, the effects of irrigation on global surface water (SW) and groundwater (GW) resources are investigated by performing simulations using Community Land Model 4.0 (CLM4) at 0.5-degree resolution driven by downscaled/bias-corrected historical simulations and future projections from five General Circulation Models (GCMs) for 1950-2099. For each climate scenario, three sets of numerical experiments were configured: (1) a control experiment (CTRL) in which all crops are assumed to be rainfed; (2) an irrigation experiment (IRRIG) in which the irrigation module using only SW for irrigation is activated; and (3) a groundwater pumping experiment (PUMP) in which a groundwater pumpingmore » scheme coupled with the irrigation module is activated for conjunctive use of SW and GW for irrigation. The parameters associated with irrigation and groundwater pumping are calibrated based on a global inventory of census-based SW and GW use compiled by the Food and Agricultural Organization (FAO). Our results suggest that irrigation could lead to two major opposing effects: SW depletion/GW accumulation in regions with irrigation primarily fed by SW, and SW accumulation/GW depletion in regions with irrigation fed primarily by GW. Furthermore, irrigation depending primarily on SW tends to have larger impacts on low-flow than high-flow conditions, suggesting the potential to increase vulnerability to drought. By the end of the 21st century (2070-2099), climate change significantly increases (relative to 1971-2000) irrigation water demand across the world. Combined with the increased temporal-spatial variability of water supply, this may lead to severe issues of local water scarcity for irrigation. Regionally, irrigation has the potential to aggravate/alleviate climate-induced changes of SW/GW although such effects are negligible when averaged globally. Our results emphasize the importance of accounting for irrigation effects and irrigation sources in regional climate change impact assessment.« less

A modeling study of irrigation effects on global surface water and groundwater resources under a changing climate

DOE PAGES

Leng, Guoyong; Huang, Maoyi; Tang, Qiuhong; ...

2015-08-25

In this paper, the effects of irrigation on global surface water (SW) and groundwater (GW) resources are investigated by performing simulations using Community Land Model 4.0 (CLM4) at 0.5-degree resolution driven by downscaled/bias-corrected historical simulations and future projections from five General Circulation Models (GCMs) for 1950-2099. For each climate scenario, three sets of numerical experiments were configured: (1) a control experiment (CTRL) in which all crops are assumed to be rainfed; (2) an irrigation experiment (IRRIG) in which the irrigation module using only SW for irrigation is activated; and (3) a groundwater pumping experiment (PUMP) in which a groundwater pumpingmore » scheme coupled with the irrigation module is activated for conjunctive use of SW and GW for irrigation. The parameters associated with irrigation and groundwater pumping are calibrated based on a global inventory of census-based SW and GW use compiled by the Food and Agricultural Organization (FAO). Our results suggest that irrigation could lead to two major opposing effects: SW depletion/GW accumulation in regions with irrigation primarily fed by SW, and SW accumulation/GW depletion in regions with irrigation fed primarily by GW. Furthermore, irrigation depending primarily on SW tends to have larger impacts on low-flow than high-flow conditions, suggesting the potential to increase vulnerability to drought. By the end of the 21st century (2070-2099), climate change significantly increases (relative to 1971-2000) irrigation water demand across the world. Combined with the increased temporal-spatial variability of water supply, this may lead to severe issues of local water scarcity for irrigation. Regionally, irrigation has the potential to aggravate/alleviate climate-induced changes of SW/GW although such effects are negligible when averaged globally. Our results emphasize the importance of accounting for irrigation effects and irrigation sources in regional climate change impact assessment.« less

Increased malaria transmission around irrigation schemes in Ethiopia and the potential of canal water management for malaria vector control.

PubMed

Kibret, Solomon; Wilson, G Glenn; Tekie, Habte; Petros, Beyene

2014-09-13

Irrigation schemes have been blamed for the increase in malaria in many parts of sub-Saharan Africa. However, proper water management could help mitigate malaria around irrigation schemes in this region. This study investigates the link between irrigation and malaria in Central Ethiopia. Larval and adult mosquitoes were collected fortnightly between November 2009 and October 2010 from two irrigated and two non-irrigated (control) villages in the Ziway area, Central Ethiopia. Daily canal water releases were recorded during the study period and bi-weekly correlation analysis was done to determine relationships between canal water releases and larval/adult vector densities. Blood meal sources (bovine vs human) and malaria sporozoite infection were tested using enzyme-linked immunosorbent assay (ELISA). Monthly malaria data were also collected from central health centre of the study villages. Monthly malaria incidence was over six-fold higher in the irrigated villages than the non-irrigated villages. The number of anopheline breeding habitats was 3.6 times higher in the irrigated villages than the non-irrigated villages and the most common Anopheles mosquito breeding habitats were waterlogged field puddles, leakage pools from irrigation canals and poorly functioning irrigation canals. Larval and adult anopheline densities were seven- and nine-fold higher in the irrigated villages than in the non-irrigated villages, respectively, during the study period. Anopheles arabiensis was the predominant species in the study area. Plasmodium falciparum sporozoite rates of An. arabiensis and Anopheles pharoensis were significantly higher in the irrigated villages than the non-irrigated villages. The annual entomological inoculation rate (EIR) calculated for the irrigated and non-irrigated villages were 34.8 and 0.25 P. falciparum infective bites per person per year, respectively. A strong positive correlation was found between bi-weekly anopheline larval density and canal water releases. Similarly, there was a strong positive correlation between bi-weekly vector density and canal water releases lagged by two weeks. Furthermore, monthly malaria incidence was strongly correlated with monthly vector density lagged by a month in the irrigated villages. The present study revealed that the irrigation schemes resulted in intensified malaria transmission due to poor canal water management. Proper canal water management could reduce vector abundance and malaria transmission in the irrigated villages.

Infection Control in Retreatment Cases: In Vivo Antibacterial Effects of 2 Instrumentation Systems.

PubMed

Rodrigues, Renata C V; Antunes, Henrique S; Neves, Mônica A S; Siqueira, José F; Rôças, Isabela N

2015-10-01

This in vivo study compared the antibacterial effects of 2 instrumentation systems in root canal-treated teeth with apical periodontitis. Forty-eight teeth with a single root and a single canal showing post-treatment apical periodontitis were selected for this study. For retreatment, teeth were randomly divided into 2 groups according to the instrumentation system used: Self-Adjusting File (SAF; ReDent-Nova, Ra'anana, Israel) and Twisted File Adaptive (TFA; SybronEndo, Orange, CA). In both groups, 2.5% sodium hypochlorite was the irrigant. Bacteriological samples were taken before (S1) and after chemomechanical preparation (S2). In the TFA group, passive ultrasonic irrigation (PUI) was performed after instrumentation, and samples were also taken after this supplementary step (S2b). DNA was extracted from the clinical samples and subjected to quantitative real-time polymerase chain reaction to evaluate the levels of total bacteria, streptococci, and Enterococcus faecalis. Statistical analyses from quantitative real-time polymerase chain reaction data were performed within groups using the Wilcoxon matched pairs test and between groups using the Mann-Whitney U test and the Fisher exact test with the significance level set at P < .05. Bacteria were detected in S1 samples from 43 teeth, which were then included in the antibacterial experiment. Both SAF and TFA instrumentation protocols showed a highly significant intracanal bacterial reduction (P < .001). Intergroup quantitative comparisons disclosed no significant differences between TFA with or without PUI and SAF (P > .05). PUI did not result in significant improvement in disinfection (P > .05). Both instrumentation systems/treatment protocols were highly effective in significantly reducing the intracanal bacterial counts. No significant difference was observed between the 2 systems in disinfecting the canals of teeth with post-treatment apical periodontitis. Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Development of Strategies for Sustainable Irrigation Water Management in Russia

NASA Astrophysics Data System (ADS)

Zeyliger, Anatoly; Ermolaeva, Olga

2013-04-01

During 1960 - 1990 years irrigated areas in Russia have increased rapidly, helping to boost agricultural output. Although the impressive achievements of irrigation in this period its large experience indicates problems and failures of irrigation water management. In addition to large water use and low irrigation water efficiency, environmental concerns (excessive water depletion, water quality reduction, water logging, soil degradation) are usually considered like the most significant problem of the irrigation sector. Despite of considerable shrinking of irrigated areas in Russia and decreasing of water withdrawal for irrigation purposes during two last decades a degradation of environment as well as degradation of soil and water resources in irrigated areas was prolonged and will probably continue if current irrigation practices are maintained. Nowadays, in different regions of Russia there are societal demand to restore agricultural irrigation in Russia as answer to challenges from climate pattern changes and degradation of land & water resources. In the respect of these demands there is a need to develop strategies for sustainability of agricultural irrigation in Russia that should be based on three main societal objectives: costeffective use of water in irrigated agriculture at farm level, and satisfactory preserving the natural environment. Therefore sustainable irrigation water management is not only an objective at farm level but also an overall goal at the local and regional as well. A way to achieve sustainability in irrigation water management is to solve the local conflicts arising from the interactions between water use at irrigation areas and surrounding environment. Thus should be based on the development of irrigation framework program including on the irrigation water management issues, policies & decisions making at federal and regional levels should be based on the indicators of environment & irrigation water efficiency monitoring promoting the use of the appropriate irrigation technologies confined to a field scale and local environmental conditions. In presented contribution a case studies of large and small irrigation schemes based on sprinklers at Saratov Region will be discussed. Analyze is focused on the identification of main causes of groundwater logging, following soil salinization and impact to surrounding environment at irrigation areas. This analyze is based on plot and field scales experimentations as well as time series about 40 years long monitoring of ground water and soils. Main conclusion from this analyze accuses current irrigation practice at this region using high irrigation dozes & intensities as well as uniformity of water application within the irrigated perimeter promoting chain of processes starting by ponding of applied water at mezodepression of soil surface, preferential flow through out macropores-cracks, wormholes, or decayed root channels and groundwater rising. Special attention is done to simulate relationships between uniform technology of water application by sprinkler and spatial nonuniformity of moisture storage (zoning of high soil moisture in depressions) in soil and as consequence of infiltration capacity. Technological alternative aimed at reducing these problems is analysed by the use of SWAP model application to uniform and nonuniform irrigation water applications. Model results indicate that use nonuniform water application technology is increasing an irrigation efficiency, increasing yield and stopping rising of groundwater. ACKNOWLEDGMENTS. This study was financially supported by FP6 DESIRE project 037046

Irrigation depth far exceeds water uptake depth in an oasis cropland in the middle reaches of Heihe River Basin

PubMed Central

Yang, Bin; Wen, Xuefa; Sun, Xiaomin

2015-01-01

Agricultural irrigation in the middle reaches of the Heihe River Basin consumes approximately 80% of the total river water. Whether the irrigation depth matches the water uptake depth of crops is one of the most important factors affecting the efficiency of irrigation water use. Our results indicated that the influence of plastic film on soil water δ18O was restricted to 0–30 cm soil depth. Based on a Bayesian model (MixSIR), we found that irrigated maize acquired water preferentially from 0–10 cm soil layer, with a median uptake proportion of 87 ± 15%. Additionally, maize utilised a mixture of irrigation and shallow soil water instead of absorbing the irrigation water directly. However, only 24.7 ± 5.5% of irrigation water remained in 0–10 cm soil layer, whereas 29.5 ± 2.8% and 38.4 ± 3.3% of the irrigation water infiltrated into 10–40 cm and 40–80 cm layers. During the 4 irrigation events, approximately 39% of the irrigation and rainwater infiltrated into soil layers below 80 cm. Reducing irrigation amount and developing water-saving irrigation methods will be important strategies for improving the efficiency of irrigation water use in this area. PMID:26463010

Comparative evaluation of the amount of debris extruded apically using conventional syringe, passive ultrasonic irrigation and EndoIrrigator Plus system: An in vitro study

PubMed Central

Shetty, Vidhi Prabhakar; Naik, Balaram Damodar; Pachlag, Amit Kashinath; Yeli, Mahantesh Mrityunjay

2017-01-01

Aim: The aim of this study is to compare the effects of conventional syringe, passive ultrasonic irrigation (PUI), and EndoIrrigator Plus on the amount of apically extruded debris. Materials and Methods: Thirty extracted human mandibular premolars were selected and randomly assigned to three groups (n = 10). The root canals were irrigated with conventional syringe, PUI, and EndoIrrigator Plus. Sodium hypochlorite was used as an irrigant, and debris was collected in a previously described experimental model (Myers and Montgomery 1991). It was then stored in an incubator at 37°C for 10 days to evaporate the irrigant before weighing the dry debris. The mean weight of debris was assessed, one-way analysis of variance was used for comparison of values, and post hoc Tukey's test was used between groups (P = 0.05). Results: The EndoIrrigator Plus group extruded significantly less debris than PUI and conventional syringe groups (P < 0.05). Furthermore, PUI group extruded significantly less debris than conventional syringe irrigation group (P < 0.05). Conclusions: 1. All the three irrigation systems were associated with apical extrusion of debris, 2. EndoIrrigator Plus system extruded significantly less debris than the PUI system and the conventional syringe irrigation system, 3. PUI system extruded significantly less debris than the conventional syringe irrigation system. PMID:29430092

The simulation of cropping pattern to improve the performance of irrigation network in Cau irrigation area

NASA Astrophysics Data System (ADS)

Wahyuningsih, Retno; Rintis Hadiani, RR; Sobriyah

2017-01-01

Cau irrigation area located in Madiun district, East Java Province, irrigates 1.232 Ha of land which covers Cau primary channel irrigation network, Wungu Secondary channel irrigation network, and Grape secondary channel irrigation network. The problems in Cau irrigation area are limited availability of water especially during the dry season (planting season II and III) and non-compliance to cropping patterns. The evaluation of irrigation system performance of Cau irrigation area needs to be done in order to know how far the irrigation system performance is, especially based on planting productivity aspect. The improvement of irrigation network performance through cropping pattern optimization is based on the increase of water necessity fulfillment (k factor), the realization of planting area and rice productivity. The research method of irrigation system performance is by analyzing the secondary data based on the Regulation of Ministry of Public Work and State Minister for Public Housing Number: 12/PRT/M/2015. The analysis of water necessity fulfillment (k factor) uses Public Work Plan Criteria Method. The performance level of planting productivity aspect in existing condition is 87.10%, alternative 1 is 93.90% dan alternative 2 is 96.90%. It means that the performance of the irrigation network from productivity aspect increases 6.80% for alternative 1 and 9.80% for alternative 2.

Evaluation of polyacrylamide on irrigation efficiency, soil conservation, and water quality in furrow irrigated Mid-South cotton production

USDA-ARS?s Scientific Manuscript database

Arkansas is a leading state in irrigated acres in the United States. As such, resulting groundwater decline and irrigation-induced soil erosion can have negative impacts. This establishes a need for irrigation management practices to improve irrigation efficiency as well as reduce soil erosion and i...

Effects of irrigation on seed production and vegetative characteristics of four moist-soil plants on impounded wetlands in California

USGS Publications Warehouse

Mushet, D.M.; Euliss, N.H.; Harris, S.W.

1992-01-01

We examined the effects of irrigation on 4 moist-soil plants commonly managed for waterfowl in the Sacramento Valley, California. Irrigation resulted in taller and heavier swamp timothy (Heleochloa schoenoides), pricklegrass (Crypsis niliaca), and sprangletop (Leptochloa fasicularis). Barnyardgrass (Echinochloa crusgalli) grew taller in irrigated wetlands, but no significant difference in weight was detected. Only sprangletop yielded larger seed masses in response to irrigation. Without irrigation, swamp timothy and pricklegrass assumed a typical prostrate growth form, but with irrigation, they assumed a vertical growth form. Irrigation did not significantly affect plant density. Because of rising water costs, wetland managers should consider wildlife management objectives and plant responses before implementing irrigation practices.

Finding of No Significant Impact and Finding of No Practicable Alternative Construction of a Warehouse Complex MacDill Air Force Base, Florida

DTIC Science & Technology

2010-05-31

that Federal agencies identify and assess environmental health and safety risks that might disproportionately affect children. The Proposed Action...extra water is sent to one irrigation field near Golf Course Avenue and Affected Environment Environmental Assessment for Warehouse Complex...the area . Environmental Consequences Environmental Assessment for Warehouse Complex MacDill AFB, Florida FEBRUARY 2010 4-15 FINAL Figure

Eavesdropping on the improved three-party quantum secret sharing protocol

NASA Astrophysics Data System (ADS)

Gao, Gan

2011-02-01

Lin et al. [Song Lin, Fei Gao, Qiao-yan Wen, Fu-chen Zhu, Opt. Commun. 281 (2008) 4553] pointed out that the multiparty quantum secret sharing protocol [Zhan-jun Zhang, Gan Gao, Xin Wang, Lian-fang Han, Shou-hua Shi, Opt. Commun. 269 (2007) 418] is not secure and proposed an improved three-party quantum secret sharing protocol. In this paper, we study the security of the improved three-party quantum secret sharing protocol and find that it is still not secure. Finally, a further improved three-party quantum secret sharing protocol is proposed.

A Secure and Efficient Handover Authentication Protocol for Wireless Networks

PubMed Central

Wang, Weijia; Hu, Lei

2014-01-01

Handover authentication protocol is a promising access control technology in the fields of WLANs and mobile wireless sensor networks. In this paper, we firstly review an efficient handover authentication protocol, named PairHand, and its existing security attacks and improvements. Then, we present an improved key recovery attack by using the linearly combining method and reanalyze its feasibility on the improved PairHand protocol. Finally, we present a new handover authentication protocol, which not only achieves the same desirable efficiency features of PairHand, but enjoys the provable security in the random oracle model. PMID:24971471

Two new Controlled not Gate Based Quantum Secret Sharing Protocols without Entanglement Attenuation

NASA Astrophysics Data System (ADS)

Zhu, Zhen-Chao; Hu, Ai-Qun; Fu, An-Min

2016-05-01

In this paper, we propose two new controlled not gate based quantum secret sharing protocols. In these two protocols, each photon only travels once, which guarantees the agents located in long distance can be able to derive the dealer's secret without suffering entanglement attenuation problem. The protocols are secure against trojan horse attack, intercept-resend attack, entangle-measure attack and entanglement-swapping attack. The theoretical efficiency for qubits of these two protocols can approach 100 %, except those used for eavesdropping checking, all entangled states can be used for final secret sharing.

Colonic irrigation for defecation disorders after dynamic graciloplasty.

PubMed

Koch, Sacha M; Uludağ, Ozenç; El Naggar, Kadri; van Gemert, Wim G; Baeten, Cor G

2008-02-01

Dynamic graciloplasty (DGP) improves anal continence and quality of life for most patients. However, in some patients, DGP fails and fecal incontinence is unsolved or only partially improved. Constipation is also a significant problem after DGP, occurring in 13-90%. Colonic irrigation can be considered as an additional or salvage treatment for defecation disorders after unsuccessful or partially successful DGP. In this study, the effectiveness of colonic irrigation for the treatment of persistent fecal incontinence and/or constipation after DGP is investigated. Patients with defecation disorders after DGP visiting the outpatient clinic of the University Hospital Maastricht were selected for colonic irrigation as additional therapy or salvage therapy in the period between January 1999 and June 2003. The Biotrol(R) Irrimatic pump or the irrigation bag was used for colonic irrigation. Relevant physical and medical history was collected. The patients were asked to fill out a detailed questionnaire about colonic irrigation. Forty-six patients were included in the study with a mean age of 59.3 +/- 12.4 years (80% female). On average, the patients started the irrigation 21.39 +/- 38.77 months after the DGP. Eight patients started irrigation before the DGP. Fifty-two percent of the patients used the irrigation as additional therapy for fecal incontinence, 24% for constipation, and 24% for both. Irrigation was usually performed in the morning. The mean frequency of irrigation was 0.90 +/- 0.40 times per day. The mean amount of water used for the irrigation was 2.27 +/- 1.75 l with a mean duration of 39 +/- 23 min. Four patients performed antegrade irrigation through a colostomy or appendicostomy, with good results. Overall, 81% of the patients were satisfied with the irrigation. Thirty-seven percent of the patients with fecal incontinence reached (pseudo-)continence, and in 30% of the patients, the constipation completely resolved. Side effects of the irrigation were reported in 61% of the patients: leakage of water after irrigation, abdominal cramps, and distended abdomen. Seven (16%) patients stopped the rectal irrigation. Colonic irrigation is an effective alternative for the treatment of persistent fecal incontinence after DGP and/or recurrent or onset constipation additional to unsuccessful or (partially) successful DGP.

Two challenges for U.S. irrigation due to climate change: increasing irrigated area in wet states and increasing irrigation rates in dry states.

PubMed

McDonald, Robert I; Girvetz, Evan H

2013-01-01

Agricultural irrigation practices will likely be affected by climate change. In this paper, we use a statistical model relating observed water use by U.S. producers to the moisture deficit, and then use this statistical model to project climate changes impact on both the fraction of agricultural land irrigated and the irrigation rate (m³ ha⁻¹). Data on water withdrawals for US states (1985-2005) show that both quantities are highly positively correlated with moisture deficit (precipitation--PET). If current trends hold, climate change would increase agricultural demand for irrigation in 2090 by 4.5-21.9 million ha (B1 scenario demand: 4.5-8.7 million ha, A2 scenario demand: 9.1-21.9 million ha). Much of this new irrigated area would occur in states that currently have a wet climate and a small fraction of their agricultural land currently irrigated, posing a challenge to policymakers in states with less experience with strict regulation of agriculture water use. Moreover, most of this expansion will occur in states where current agricultural production has relatively low market value per hectare, which may make installation of irrigation uneconomical without significant changes in crops or practices by producers. Without significant increases in irrigation efficiency, climate change would also increase the average irrigation rate from 7,963 to 8,400-10,415 m³ ha⁻¹ (B1 rate: 8,400-9,145 m³ ha⁻¹, A2 rate: 9,380-10,415 m³ ha⁻¹). The irrigation rate will increase the most in states that already have dry climates and large irrigation rates, posing a challenge for water supply systems in these states. Accounting for both the increase in irrigated area and irrigation rate, total withdrawals might increase by 47.7-283.4 billion m³ (B1 withdrawal: 47.7-106.0 billion m³, A2 withdrawal: 117.4-283.4 billion m³). Increases in irrigation water-use efficiency, particularly by reducing the prevalence of surface irrigation, could eliminate the increase in total irrigation withdrawals in many states.

Effect of irrigation and stainless steel drills on dental implant bed heat generation.

PubMed

Bullon, B; Bueno, E F; Herrero, M; Fernandez-Palacin, A; Rios, J V; Bullon, P; Gil, F J

2015-02-01

The objective of this study is assessing the influence of the use of different drill types and external irrigation on heat generation in the bone. In-vitro study to compare two different sequences for implant-bed preparation by means of two stainless steels: precipitation-hardening stainless steel (AISI 420B) (K drills), and martensitic stainless steel (AISI 440) (S drills). Besides, the drilled sequences were realized without irrigation, and with external irrigation by means of normal saline solution at room temperature. The study was realized on bovine ribs using: K without irrigation (KSI) and with irrigation (KCI) and S without irrigation (SSI) and with irrigation (SCI) with five drills for each system. Each drill was used 100 times. Bone temperature was measured with a thermocouple immediately after drilled. Average bone temperature with irrigation was for K drills 17.58±3.32 °C and for S drills 16.66±1.30 °C. Average bone temperature without irrigation was for K drills 23.58±2.94 °C and for S drills 19.41±2.27 °C. Statistically significant differences were found between K without irrigation versus S with irrigation and K with irrigation (p<0.05, Bonferroni correction). Lower temperature variation coefficient throughout the 50 measurements was observed in irrigated groups (K=5.6%, S=5.1% vs. without irrigation groups K=9.4%, S=9.3%). The first K drill generated more heat than the remaining drills. No significant differences were detected among temperature values in any of the analyzed drill groups. Unlike irrigation, drill use and type were observed to have no significant impact on heat generation. The stainless steel AISI 420B presents better mechanical properties and corrosion resistance than AISI440.

Remote sensing based water-use efficiency evaluation in sub-surface irrigated wine grape vines

NASA Astrophysics Data System (ADS)

Zúñiga, Carlos Espinoza; Khot, Lav R.; Jacoby, Pete; Sankaran, Sindhuja

2016-05-01

Increased water demands have forced agriculture industry to investigate better irrigation management strategies in crop production. Efficient irrigation systems, improved irrigation scheduling, and selection of crop varieties with better water-use efficiencies can aid towards conserving water. In an ongoing experiment carried on in Red Mountain American Viticulture area near Benton City, Washington, subsurface drip irrigation treatments at 30, 60 and 90 cm depth, and 15, 30 and 60% irrigation were applied to satisfy evapotranspiration demand using pulse and continuous irrigation. These treatments were compared to continuous surface irrigation applied at 100% evapotranspiration demand. Thermal infrared and multispectral images were acquired using unmanned aerial vehicle during the growing season. Obtained results indicated no difference in yield among treatments (p<0.05), however there was statistical difference in leaf temperature comparing surface and subsurface irrigation (p<0.05). Normalized vegetation index obtained from the analysis of multispectral images showed statistical difference among treatments when surface and subsurface irrigation methods were compared. Similar differences in vegetation index values were observed, when irrigation rates were compared. Obtained results show the applicability of aerial thermal infrared and multispectral images to characterize plant responses to different irrigation treatments and use of such information in irrigation scheduling or high-throughput selection of water-use efficient crop varieties in plant breeding.

[Effects of irrigation and planting pattern on winter wheat water consumption characteristics and dry matter production].

PubMed

Dong, Hao; Chen, Yu-Hai; Zhou, Xun-Bo

2013-07-01

Taking high-yield winter wheat cultivar 'Jimai 22' as test material, a field experiment was conducted in 2008-2010 to study the effects of different irrigation and planting modes on the water consumption characteristics and dry matter accumulation and distribution of winter wheat. Three planting patterns (uniform row, wide-narrow row, and furrow) and four irrigation schedules (no irrigation, W0; irrigation at jointing stage, W1; irrigation at jointing and anthesis stages, W2; and irrigation at jointing, anthesis, and milking stages, W3; with 60 mm per irrigation) were installed. With increasing amount of irrigation, the total water consumption and the ratio of irrigation water to total water consumption under different planting patterns all increased, while the soil water consumption and its ratio to total water consumption decreased significantly. As compared with W0, the other three irrigation schedules had a higher dry matter accumulation after anthesis and a higher grain yield, but a lower water use efficiency (WUE). Under the same irrigation schedules, furrow pattern had higher water consumption ratio, grain yield, and WUE. Taking the grain yield and WUE into consideration, furrow pattern combined with irrigation at jointing and anthesis stages would be the optimal water-saving and planting modes for the winter wheat production in North China Plain.

Irrigation Requirement Estimation Using Vegetation Indices and Inverse Biophysical Modeling

NASA Technical Reports Server (NTRS)

Bounoua, Lahouari; Imhoff, Marc L.; Franks, Shannon

2010-01-01

We explore an inverse biophysical modeling process forced by satellite and climatological data to quantify irrigation requirements in semi-arid agricultural areas. We constrain the carbon and water cycles modeled under both equilibrium, balance between vegetation and climate, and non-equilibrium, water added through irrigation. We postulate that the degree to which irrigated dry lands vary from equilibrium climate conditions is related to the amount of irrigation. The amount of water required over and above precipitation is considered as an irrigation requirement. For July, results show that spray irrigation resulted in an additional amount of water of 1.3 mm per occurrence with a frequency of 24.6 hours. In contrast, the drip irrigation required only 0.6 mm every 45.6 hours or 46% of that simulated by the spray irrigation. The modeled estimates account for 87% of the total reported irrigation water use, when soil salinity is not important and 66% in saline lands.

Determination of irrigation pumpage in parts of Kearny and Finney Counties, southwestern Kansas

USGS Publications Warehouse

Lindgren, R.J.

1982-01-01

Irrigation pumpage was determined for parts of Kearny and Finney Counties in Southwestern Kansas using crop-acreage data and consumptive, irrigation-water requirements. Irrigated acreages for 1974-80 were compiled for wheat, grain sorghum, corn, and alfalfa using records from the U.S. Agricultural Stabilization and Conservation Service. Consumptive-irrigation requirements were computed using a soil-moisture model. The model tabulated monthly soil-moisture and crop-water demand for various crops and computed the volume of irrigation water needed to maintain the available moisture at 50% for loamy soils or at 60% for sandy soils. Irrigated acres in the study area increased from 265,000 acres during 1974 to 321,000 acres during 1980. Irrigation pumpage increased from 584,000 acre-feet during 1974 to 738,000 acre-feet during 1980. Decreased consumptive-irrigation requirements during 1979 resulted in a comparatively small irrigation-pumpage estimate of 458,000 acre-feet. (USGS)

Effects of different deficit irrigation on sugar accumulation of pineapple during development

NASA Astrophysics Data System (ADS)

Feng, Haiyan; Du, Liqing; Liu, Shenghui; Zhang, Xiumei

2017-08-01

The potted pineapple cultivar ‘Comte de paris’ was used to study the influence of deficit irrigation on fruit sugar accumulation in greenhouse during the fruit enlargement period. The study included a control (normal irrigation) and two treatment groups, moderate deficit (50% of the control irrigation) and severe deficit (25% of the control irrigation). The results indicated that the deficit irrigation significantly decreased the sucrose accumulation. The sucrose content in the fruits of moderate deficit irrigation was the lowest. During the mature period, the deficit irrigation decreased the sucrose phosophate synthase activity(SPS) an increased the sucrose synthase (SS) and neutral invertase (NI). The moderate deficit irrigation significantly improved the acid invertase activity(AI). However, it was inhibited by the severe deficit irrigation. In general, the moderate treatment reduced the SPS activity and enhanced the NI and AI activities, while the severe treatment decreased the SPS and AI activities.

Cognitive Protocol Stack Design

DTIC Science & Technology

2015-12-30

SECURITY CLASSIFICATION OF: In the ARO “ Cognitive Protocol Stack Design" project we proposed cognitive networking solutions published in international...areas related to cognitive networking, opening also new lines of research that was not possible to forecast at the beginning of the project. In a...Distribution Unlimited Final Report: Cognitive Protocol Stack Design The views, opinions and/or findings contained in this report are those of the author(s

Detecting Hidden Communications Protocols

DTIC Science & Technology

2013-02-11

Protocols FA9550-09-1-0173 Richard R Brooks Clemson University PO Box 340915 Clemson, SC 29634-0915 Air Force Office of Scientific Research/RSL 875...two botnet detection methods: centralized botnet traffic detection using HMMs and probabilistic context-free grammars (PCFGs) for centralized and...final report for the Detecting Hidden Communications Protocols AFOSR grant with R. R. Brooks form Clemson University as PI. The work funded by the

Genotypic variation in transpiration efficiency due to differences in photosynthetic capacity among sugarcane-related clones

PubMed Central

Li, Chunjia; Lu, Xin; Xu, Chaohua; Cai, Qing; Basnayake, Jayapathi; Lakshmanan, Prakash; Ghannoum, Oula; Fan, Yuanhong

2017-01-01

Abstract Sugarcane, derived from the hybridization of Saccharum officinarum×Saccharum spontaneum, is a vegetative crop in which the final yield is highly driven by culm biomass production. Cane yield under irrigated or rain-fed conditions could be improved by developing genotypes with leaves that have high intrinsic transpiration efficiency, TEi (CO2 assimilation/stomatal conductance), provided this is not offset by negative impacts from reduced conductance and growth rates. This study was conducted to partition genotypic variation in TEi among a sample of diverse clones from the Chinese collection of sugarcane-related germplasm into that due to variation in stomatal conductance versus that due to variation in photosynthetic capacity. A secondary goal was to define protocols for optimized larger-scale screening of germplasm collections. Genotypic variation in TEi was attributed to significant variation in both stomatal and photosynthetic components. A number of genotypes were found to possess high TEi as a result of high photosynthetic capacity. This trait combination is expected to be of significant breeding value. It was determined that a small number of observations (16) is sufficient for efficiently screening TEi in larger populations of sugarcane genotypes The research methodology and results reported are encouraging in supporting a larger-scale screening and introgression of high transpiration efficiency in sugarcane breeding. However, further research is required to quantify narrow sense heritability as well as the leaf-to-field translational potential of genotypic variation in transpiration efficiency-related traits observed in this study. PMID:28444313

Irrigation of human prepared root canal – ex vivo based computational fluid dynamics analysis

PubMed Central

Šnjarić, Damir; Čarija, Zoran; Braut, Alen; Halaji, Adelaida; Kovačević, Maja; Kuiš, Davor

2012-01-01

Aim To analyze the influence of the needle type, insertion depth, and irrigant flow rate on irrigant flow pattern, flow velocity, and apical pressure by ex-vivo based endodontic irrigation computational fluid dynamics (CFD) analysis. Methods Human upper canine root canal was prepared using rotary files. Contrast fluid was introduced in the root canal and scanned by computed tomography (CT) providing a three-dimensional object that was exported to the computer-assisted design (CAD) software. Two probe points were established in the apical portion of the root canal model for flow velocity and pressure measurement. Three different CAD models of 27G irrigation needles (closed-end side-vented, notched open-end, and bevel open-end) were created and placed at 25, 50, 75, and 95% of the working length (WL). Flow rates of 0.05, 0.1, 0.2, 0.3, and 0.4 mL/s were simulated. A total of 60 irrigation simulations were performed by CFD fluid flow solver. Results Closed-end side-vented needle required insertion depth closer to WL, regarding efficient irrigant replacement, compared to open-end irrigation needle types, which besides increased velocity produced increased irrigant apical pressure. For all irrigation needle types and needle insertion depths, the increase of flow rate was followed by an increased irrigant apical pressure. Conclusions The human root canal shape obtained by CT is applicable in the CFD analysis of endodontic irrigation. All the analyzed values –irrigant flow pattern, velocity, and pressure – were influenced by irrigation needle type, as well as needle insertion depth and irrigant flow rate. PMID:23100209

Irrigation of human prepared root canal--ex vivo based computational fluid dynamics analysis.

PubMed

Snjaric, Damir; Carija, Zoran; Braut, Alen; Halaji, Adelaida; Kovacevic, Maja; Kuis, Davor

2012-10-01

To analyze the influence of the needle type, insertion depth, and irrigant flow rate on irrigant flow pattern, flow velocity, and apical pressure by ex-vivo based endodontic irrigation computational fluid dynamics (CFD) analysis. Human upper canine root canal was prepared using rotary files. Contrast fluid was introduced in the root canal and scanned by computed tomography (CT) providing a three-dimensional object that was exported to the computer-assisted design (CAD) software. Two probe points were established in the apical portion of the root canal model for flow velocity and pressure measurement. Three different CAD models of 27G irrigation needles (closed-end side-vented, notched open-end, and bevel open-end) were created and placed at 25, 50, 75, and 95% of the working length (WL). Flow rates of 0.05, 0.1, 0.2, 0.3, and 0.4 mL/s were simulated. A total of 60 irrigation simulations were performed by CFD fluid flow solver. Closed-end side-vented needle required insertion depth closer to WL, regarding efficient irrigant replacement, compared to open-end irrigation needle types, which besides increased velocity produced increased irrigant apical pressure. For all irrigation needle types and needle insertion depths, the increase of flow rate was followed by an increased irrigant apical pressure. The human root canal shape obtained by CT is applicable in the CFD analysis of endodontic irrigation. All the analyzed values -irrigant flow pattern, velocity, and pressure - were influenced by irrigation needle type, as well as needle insertion depth and irrigant flow rate.

Comparison of the EndoVac system to needle irrigation of root canals.

PubMed

Nielsen, Benjamin A; Craig Baumgartner, J

2007-05-01

Past studies have shown that current irrigation methods are effective at cleaning root canals coronally but less effective apically. To be effective, endodontic irrigants should ideally be delivered near working length. The purpose of this study was to compare the efficacy of the EndoVac irrigation system and needle irrigation to debride root canals at 1 and 3 mm from working length. One tooth of each matched pair was instrumented and irrigated by using the EndoVac, which uses negative pressure to deliver irrigating solutions to working length. The other tooth of the matched pair was instrumented and irrigated with a 30-gauge ProRinse irrigating needle. All teeth were irrigated with sodium hypochlorite (NaOCl) and ethylenediaminetetraacetic acid (EDTA) for a predetermined amount of time, and total volume of irrigant used was recorded. After instrumentation and irrigation, the teeth were fixed, decalcified, and sectioned at 1 mm and 3 mm from working length. Serial sections were made and digitally photographed. The amount of remaining debris was determined as a percentage of the area of the canal lumen. Remaining debris and total irrigant were analyzed by using the Wilcoxon signed rank test at the 5% confidence level. At the 1-mm level, significantly less debris was found in the EndoVac group (p=0.0347). At the 3-mm level, there was no significant difference between groups. Significantly more irrigant was delivered with the EndoVac (p<0001). This study showed significantly better debridement at 1 mm from working length by using the EndoVac compared with needle irrigation.

Water and energy conservation through efficient irrigation management. Project completion report, January 1, 1975-December 1976

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stone, L.R.

An evaluation was made of corn (Zea mays L.) and grain sorghum (Sorghum bicolor (L) Moench) yield and water use efficiency as influenced by irrigation timing. The study was located at Tribune (mean annual rainfall of 17.0 inches) and Manhattan, (mean annual rainfall of 33.5 inches) Kansas. Treatments consisted of no in-season irrigation, a single in-season irrigation at one of three different growth stages, and irrigating at each of the three selected growth stages. Selected growth stages in corn were pre-tassel, silk emergence, and blister; in grain sorghum they were boot, half-bloom, and soft-dough. Each irrigation was 4 inches atmore » Manhattan and 6 inches at Tribune. All Tribune plots received a pre-plant irrigation in April of each year. Water was applied to basin plots using gated pipe. With no in-season irrigation, the 3-year mean grain sorghum yields were greater than corn yields at both Manhattan and Tribune. The largest 3-year mean yield for corn receiving a single in-season irrigation was obtained with the irrigation during silk emergence at both Manhattan and Tribune. Grain sorghum yields from the single in-season irrigation treatments were similar and presented no single time that tended to be superior during the three study years. Corn responded well to the three in-season irrigations. The grain sorghum yield increase for plots receiving three in-season irrigations as opposed to those receiving only one in-season irrigation is insufficient to justify the two additional irrigations.« less

A comprehensive guide for designing more efficient irrigation systems with respect to application control

NASA Astrophysics Data System (ADS)

Khaddam, Issam; Schuetze, Niels

2017-04-01

The worldwide water scarcity problems are expected to aggravate due to the increasing population and the need to produce more food. Irrigated agriculture is considered the highest consumer of fresh water resources with a rate exceeds 70% of global consumption. Consequently, an improvement in the efficiency of all irrigation methods, such as furrow or drip irrigation, becomes more necessary and urgent. Therefore, a more precise knowledge about soil water distribution in the root zone and the water balance components is required. For this purpose and as a part of the SAPHIR project (Saxonian Platform for high Performance Irrigation), a 2D simulation- based study was performed with virtual field conditions. The study investigates the most important design parameters of many irrigation systems, such as irrigation intensity and duration, and shows there influence on the water distribution efficiency. Furthermore, three main soil textures are used to test the impact of the soil hydraulic properties on irrigation effectiveness. A numerous number of irrigation scenarios of each irrigation system was simulated using HYDRUS 2D. Thereafter, the results were digitally calculated, compiled and made available online in the so called "Irrigation Atlases". The irrigation atlases provide graphical results of the soil moisture and pressure head distributions in the root zone. Moreover, they contain detailed information of the water balance for all simulated scenarios. The most studies evaluate the irrigation water demands on local, regional or global scales and for that an efficient water distribution is required. In this context, the irrigation atlases can serve as a valuable tool for the implementation of planned irrigation measures.

Summary of the Georgia Agricultural Water Conservation and Metering Program and evaluation of methods used to collect and analyze irrigation data in the middle and lower Chattahoochee and Flint River basins, 2004-2010

USGS Publications Warehouse

Torak, Lynn J.; Painter, Jaime A.

2011-01-01

Since receiving jurisdiction from the State Legislature in June 2003 to implement the Georgia Agricultural Water Conservation and Metering Program, the Georgia Soil and Water Conservation Commission (Commission) by year-end 2010 installed more than 10,000 annually read water meters and nearly 200 daily reporting, satellite-transmitted, telemetry sites on irrigation systems located primarily in southern Georgia. More than 3,000 annually reported meters and 50 telemetry sites were installed during 2010 alone. The Commission monitored rates and volumes of agricultural irrigation supplied by groundwater, surface-water, and well-to-pond sources to inform water managers on the patterns and amounts of such water use and to determine effective and efficient resource utilization. Summary analyses of 4 complete years of irrigation data collected from annually read water meters in the middle and lower Chattahoochee and Flint River basins during 2007-2010 indicated that groundwater-supplied fields received slightly more irrigation depth per acre than surface-water-supplied fields. Year 2007 yielded the largest disparity between irrigation depth supplied by groundwater and surface-water sources as farmers responded to severe-to-exceptional drought conditions with increased irrigation. Groundwater sources (wells and well-to-pond systems) outnumbered surface-water sources by a factor of five; each groundwater source applied a third more irrigation volume than surface water; and, total irrigation volume from groundwater exceeded that of surface water by a factor of 6.7. Metered irrigation volume indicated a pattern of low-to-high water use from northwest to southeast that could point to relations between agricultural water use, water-resource potential and availability, soil type, and crop patterns. Normalizing metered irrigation-volume data by factoring out irrigated acres allowed irrigation water use to be expressed as an irrigation depth and nearly eliminated the disparity between volumes of applied irrigation derived from groundwater and surface water. Analysis of per-acre irrigation depths provided a commonality for comparing irrigation practices across the entire range of field sizes in southern Georgia and indicated underreporting of irrigated acres for some systems. Well-to-pond systems supplied irrigation at depths similar to groundwater and can be combined with groundwater irrigation data for subsequent analyses. Average irrigation depths during 2010 indicated an increase from average irrigation depths during 2008 and 2009, most likely the result of relatively dry conditions during 2010 compared to conditions in 2008 and 2009. Geostatistical models facilitated estimation of irrigation water use for unmetered systems and demonstrated usefulness in redesigning the telemetry network. Geospatial analysis evaluated the ability of the telemetry network to represent annually reported water-meter data and presented an objective, unbiased method for revising the network.

Irrigation: Erosion

USDA-ARS?s Scientific Manuscript database

Irrigation is essential for global food production. However, irrigation erosion can limit the ability of irrigation systems to reliably produce food and fiber in the future. The factors affecting soil erosion from irrigation are the same as rainfall—water detaches and transports sediment. However, t...

Wireless sensor networks for irrigation management

USDA-ARS?s Scientific Manuscript database

Sustaining an adequate food supply for the world's population will require advancements in irrigation technology and improved irrigation management. Site-specific irrigation and automatic irrigation scheduling are examples of strategies to deal with declining arable land and limited fresh water reso...

Remotely sensed high resolution irrigated area mapping in India for 2000 to 2015

PubMed Central

Ambika, Anukesh Krishnankutty; Wardlow, Brian; Mishra, Vimal

2016-01-01

India is among the countries that uses a significant fraction of available water for irrigation. Irrigated area in India has increased substantially after the Green revolution and both surface and groundwater have been extensively used. Under warming climate projections, irrigation frequency may increase leading to increased irrigation water demands. Water resources planning and management in agriculture need spatially-explicit irrigated area information for different crops and different crop growing seasons. However, annual, high-resolution irrigated area maps for India for an extended historical record that can be used for water resources planning and management are unavailable. Using 250 m normalized difference vegetation index (NDVI) data from Moderate Resolution Imaging Spectroradiometer (MODIS) and 56 m land use/land cover data, high-resolution irrigated area maps are developed for all the agroecological zones in India for the period of 2000–2015. The irrigated area maps were evaluated using the agricultural statistics data from ground surveys and were compared with the previously developed irrigation maps. High resolution (250 m) irrigated area maps showed satisfactory accuracy (R2=0.95) and can be used to understand interannual variability in irrigated area at various spatial scales. PMID:27996974

Comparative study of irrigation water use and groundwater recharge under various irrigation schemes in an agricultural region, central Taiwan

NASA Astrophysics Data System (ADS)

Chen, Shih-Kai; Jang, Cheng-Shin; Tsai, Cheng-Bin

2016-04-01

The risk of rice production has increased notably due to climate change in Taiwan. To respond to growing agricultural water shortage without affecting normal food production in the future, the application of water-saving irrigation will be a substantial resolution. However, the adoption of water-saving irrigation may result in the reducing of groundwater recharge because continuous flooding in the paddy fields could be regarded as an important source for groundwater recharge. The aim of this study was to evaluate the irrigation water-saving benefit and groundwater recharge deficit when adopting the System of Rice Intensification, known as SRI methodology, in the Choushui River alluvial fan (the largest groundwater pumping and the most important rice-cropping region in central Taiwan). The three-dimensional finite element groundwater model, FEMWATER, was applied to simulate the infiltration process and groundwater recharge under SRI methodology and traditional irrigation schemes including continuous irrigation, and rotational irrigation in two rice-crop periods with hydro-climatic data of 2013. The irrigation water use was then calculated by water balance. The results showed that groundwater recharge amount of SRI methodology was slightly lower than those of traditional irrigation schemes, reduced 3.6% and 1.6% in the first crop period, and reduced 3.2% and 1.6% in the second crop period, compared with continuous irrigation and rotational irrigation, respectively. However, the SRI methodology achieved notably water-saving benefit compared to the disadvantage of reducing the groundwater recharge amount. The field irrigation requirement amount of SRI methodology was significantly lower than those of traditional irrigation schemes, saving 37% and 20% of irrigation water in the first crop period, and saving 53% and 35% in the second crop period, compared with continuous irrigation and rotational irrigation, respectively. Therefore, the amount of groundwater pumping for irrigation water use can be reduced when adopting the SRI methodology in the future. The reducing of groundwater recharge could be supplemented by using 1,500 hectares of fallow paddy fields, located at proximal-fan region, as recharge pools in the wet season. The adoption of water-saving irrigation would be helpful for the relevant government agency to formulate the integral water resource management strategies in this region. Keywords:Groundwater recharge, SRI, FEMWATER, Field irrigation requirement

Improving irrigation management in L'Horta Nord (Valencia, Spain)

NASA Astrophysics Data System (ADS)

Pascual-Seva, Nuria; San Bautista, Alberto; López-Galarza, Salvador; Maroto, Jose Vicente; Pascual, Bernardo

2014-05-01

L'Horta Nord is an important irrigation district in Valencia (Spain), especially for vegetable crops. The traditional cropping pattern in the region consists of a rotation of chufa with crops such as potato, onion, lettuce, escarole and red cabbage, being all these crops furrow irrigated. Currently, the quality of the water used is acceptable, water is not expensive and there are no limitations on supply. Consequently, growers are not aware of the volumes of water used, application efficiencies, nor water productivity for any of the crops cited. The European Framework Directive 2000/60, based on the precautionary principle, considers preventive action for measures to be taken; moreover, drought periods are becoming more frequent and extended, and water is being diverted to other uses. Thus, water use is an issue to improve. In this sense, the current situation of the irrigation in the area is analysed using chufa (Cyperus esculentus L. var. sativus Boeck.) as representative of the crops, since most of the crops in the area have shallow root systems, as chufa, which are irrigated in similar patterns. In order to analyse the irrigation performance of the traditional chufa crop as well as to achieve more sustainable results, different studies have been carried out, during the last decade. Efforts have been directed to increase water productivity, increasing yield and minimising the volumes of water applied. Different planting configurations and different irrigation thresholds, not only in furrow irrigation but also in drip irrigation, are examples of how the irrigation performance could be improved. Herein is presented a two-year study, comparing, in both furrow and drip irrigation, two irrigation schedules based on the volumetric soil water content, which was continuously monitored using capacitance sensors. Yield was significantly affected by the growing season, the irrigation system and by the irrigation schedule, and by the second order interactions of the irrigation system with the other studied variables. Greater yields (p≤0.01) were obtained in the first growing season, drip irrigation and maintaining a higher soil moisture level. When considering the irrigation water use efficiency, the irrigation system showed significant differences (p≤0.01) with greater efficiencies for drip irrigation. Considering the homogeneity of the plots in the area and the similarities of the irrigation managements of chufa with the other crops, the results could be extended to most of the plots and crops in the area.

Quantitative PCR and Digital PCR for Detection of Ascaris lumbricoides Eggs in Reclaimed Water

PubMed Central

Santísima-Trinidad, Ana Belén; Bornay-Llinares, Fernando Jorge; Martín González, Marcos; Pascual Valero, José Antonio; Ros Muñoz, Margarita

2017-01-01

The reuse of reclaimed water from wastewater depuration is a widespread and necessary practice in many areas around the world and must be accompanied by adequate and continuous quality control. Ascaris lumbricoides is one of the soil-transmitted helminths (STH) with risk for humans due to its high infectivity and an important determinant of transmission is the inadequacy of water supplies and sanitation. The World Health Organization (WHO) recommends a limit equal to or lower than one parasitic helminth egg per liter, to reuse reclaimed water for unrestricted irrigation. We present two new protocols of DNA extraction from large volumes of reclaimed water. Quantitative PCR (qPCR) and digital PCR (dPCR) were able to detect low amounts of A. lumbricoides eggs. By using the first extraction protocol, which processes 500 mL of reclaimed water, qPCR can detect DNA concentrations as low as one A. lumbricoides egg equivalent, while dPCR can detect DNA concentrations as low as five A. lumbricoides egg equivalents. By using the second protocol, which processes 10 L of reclaimed water, qPCR was able to detect DNA concentrations equivalent to 20 A. lumbricoides eggs. This fact indicated the importance of developing new methodologies to detect helminth eggs with higher sensitivity and precision avoiding possible human infection risks. PMID:28377928

Expanding the Annual Irrigation Maps (AIM) Product to the entire High Plains Aquifer (HPA): Addressing the Challenges of Cotton and Deficit-Irrigated Fields

NASA Astrophysics Data System (ADS)

Rapp, J. R.; Deines, J. M.; Kendall, A. D.; Hyndman, D. W.

2017-12-01

The High Plains Aquifer (HPA) is the most extensively irrigated aquifer in the continental United States and is the largest major aquifer in North America with an area of 500,000 km2. Increased demand for agricultural products has led to expanded irrigation extent, but brought with it declining groundwater levels that have made irrigation unsustainable in some locations. Understanding these irrigation dynamics and mapping irrigated areas through time are essential for future sustainable agricultural practices and hydrological modeling. Map products using remote sensing have only recently been able to track annual dynamics at relatively high spatial resolution (30 m) for a large portion of the northern HPA. However follow-on efforts to expand these maps to the entire HPA have met with difficulty due to the challenge of distinguishing irrigation in crop types that are commonly deficit- or partially-irrigated. Expanding these maps to the full HPA requires addressing unique features of partially irrigated fields and irrigated cotton, a major water user in the southern HPA. Working in Google Earth Engine, we used all available Landsat imagery to generate annual time series of vegetation indices. We combined this information with climate covariables, planting dates, and crop specific training data to algorithmically separate fully irrigated, partially irrigated, and non-irrigated field locations. The classification scheme was then applied to produce annual maps of irrigation across the entire HPA. The extensive use of ancillary data and the "greenness" time series for the algorithmic classification generally increased accuracy relative to previous efforts. High-accuracy, representative map products of irrigation extent capable of detecting crop type and irrigation intensity within aquifers will be an essential tool to monitor the sustainability of global aquifers and to provide a scientific bases for political and economic decisions affecting those aquifers.

Reduced irrigation increases the water use efficiency and productivity of winter wheat-summer maize rotation on the North China Plain.

PubMed

Wang, Yunqi; Zhang, Yinghua; Zhang, Rui; Li, Jinpeng; Zhang, Meng; Zhou, Shunli; Wang, Zhimin

2018-03-15

The groundwater table has fallen sharply over the last 30years on the North China Plain, resulting in a shortage of water for winter wheat irrigation. Reducing irrigation may be an important strategy to maintain agricultural sustainability in the region; however, few studies have evaluated the transition from conventional irrigation management practices to reduced irrigation management practices in the winter wheat-summer maize rotation system. Here, we compare the yield, water consumption, and water use efficiency of winter wheat-summer maize rotation under conventional irrigation and reduced irrigation on the North China Plain from 2012 to 2015. Reducing irrigation decreased the yield but increased the water use efficiency and significantly advanced the harvest date of winter wheat. As a result, the summer maize sowing date advanced significantly, and the flowering date subsequently advanced 2-8days, thus extending the summer maize grain-filling stage. Therefore, the yield and water use efficiency of summer maize were higher under reduced irrigation than conventional irrigation, which compensated for the winter wheat yield loss under reduced irrigation. In addition, under reduced irrigation from 2012 to 2015, the yield and water use efficiency advantage of the winter wheat-summer maize rotation ranged from 0.0 to 9.7% and from 4.1 to 14.7%, respectively, and water consumption and irrigated water decreased by 20-61mm and 150mm, respectively, compared to conventional irrigation. Overall, the reduced irrigation management practice involving no irrigation after sowing winter wheat, and sowing summer maize on June 7 produced the most favorable grain yield with superb water use efficiency in the winter wheat-summer maize rotation. This study indicates that reducing irrigation could be an efficient means to cope with water resource shortages while maintaining crop production sustainability on the North China Plain. Copyright © 2017. Published by Elsevier B.V.

Seasonal effects of irrigation on land-atmosphere latent heat, sensible heat, and carbon fluxes in semiarid basin

NASA Astrophysics Data System (ADS)

Zeng, Yujin; Xie, Zhenghui; Liu, Shuang

2017-02-01

Irrigation, which constitutes ˜ 70 % of the total amount of freshwater consumed by the human population, is significantly impacting land-atmosphere fluxes. In this study, using the improved Community Land Model version 4.5 (CLM4.5) with an active crop model, two high-resolution (˜ 1 km) simulations investigating the effects of irrigation on latent heat (LH), sensible heat (SH), and carbon fluxes (or net ecosystem exchange, NEE) from land to atmosphere in the Heihe River basin in northwestern China were conducted using a high-quality irrigation dataset compiled from 1981 to 2013. The model output and measurements from remote sensing demonstrated the capacity of the developed models to reproduce ecological and hydrological processes. The results revealed that the effects of irrigation on LH and SH are strongest during summer, with a LH increase of ˜ 100 W m-2 and a SH decrease of ˜ 60 W m-2 over intensely irrigated areas. However, the reactions are much weaker during spring and autumn when there is much less irrigation. When the irrigation rate is below 5 mm day-1, the LH generally increases, whereas the SH decreases with growing irrigation rates. However, when the irrigation threshold is in excess of 5 mm day-1, there is no accrued effect of irrigation on the LH and SH. Irrigation produces opposite effects to the NEE during spring and summer. During the spring, irrigation yields more discharged carbon from the land to the atmosphere, increasing the NEE value by 0.4-0.8 gC m-2 day-1, while the summer irrigation favors crop fixing of carbon from atmospheric CO2, decreasing the NEE value by ˜ 0.8 gC m-2 day-1. The repercussions of irrigation on land-atmosphere fluxes are not solely linked to the irrigation amount, and other parameters (especially the temperature) also control the effects of irrigation on LH, SH, and NEE.

Estimation of Infiltration Parameters and the Irrigation Coefficients with the Surface Irrigation Advance Distance

PubMed Central

Beibei, Zhou; Quanjiu, Wang; Shuai, Tan

2014-01-01

A theory based on Manning roughness equation, Philip equation and water balance equation was developed which only employed the advance distance in the calculation of the infiltration parameters and irrigation coefficients in both the border irrigation and the surge irrigation. The improved procedure was validated with both the border irrigation and surge irrigation experiments. The main results are shown as follows. Infiltration parameters of the Philip equation could be calculated accurately only using water advance distance in the irrigation process comparing to the experimental data. With the calculated parameters and the water balance equation, the irrigation coefficients were also estimated. The water advance velocity should be measured at about 0.5 m to 1.0 m far from the water advance in the experimental corn fields. PMID:25061664

Effects of Irrigation on Global Climate During the 20th Century

NASA Technical Reports Server (NTRS)

Puma, M. J.; Cook, B. I.

2010-01-01

Various studies have documented the effects of modern ]day irrigation on regional and global climate, but none, to date, have considered the time ]varying impact of steadily increasing irrigation rates on climate during the 20th century. We investigate the impacts of observed irrigation changes over this century with two ensemble simulations using an atmosphere general circulation model. Both ensembles are forced with transient climate forcings and observed sea surface temperatures from 1902 to 2000; one ensemble includes irrigation specified by a time ]varying data set of irrigation water withdrawals. Early in the century, irrigation is primarily localized over southern and eastern Asia, leading to significant cooling in boreal summer (June.August) over these regions. This cooling spreads and intensifies by century fs end, following the rapid expansion of irrigation over North America, Europe, and Asia. Irrigation also leads to boreal winter (December.February) warming over parts of North America and Asia in the latter part of the century, due to enhanced downward longwave fluxes from increased near ]surface humidity. Precipitation increases occur primarily downwind of the major irrigation areas, although precipitation in parts of India decreases due to a weaker summer monsoon. Irrigation begins to significantly reduce temperatures and temperature trends during boreal summer over the Northern Hemisphere midlatitudes and tropics beginning around 1950; significant increases in precipitation occur in these same latitude bands. These trends reveal the varying importance of irrigation ]climate interactions and suggest that future climate studies should account for irrigation, especially in regions with unsustainable irrigation resources.

Biofilm removal by 6% sodium hypochlorite activated by different irrigation techniques.

PubMed

Ordinola-Zapata, R; Bramante, C M; Aprecio, R M; Handysides, R; Jaramillo, D E

2014-07-01

To compare the removal of biofilm utilizing four irrigation techniques on a bovine root canal model. Fifty dentine specimens (2 × 2 mm) were infected with biofilm. The samples were then adapted to previously created cavities in the bovine model. The root canals were irrigated twice with 2 mL of 6% sodium hypochlorite for 2 min (4 min total). Following initial irrigation, the different treatment modalities were introduced for 60 s (3 × 20 s intervals). The evaluated techniques were needle irrigation, Endoactivator (Dentsply Tulsa Dental, Tulsa, OK, USA), passive ultrasonic irrigation and laser-activated irrigation (photon-induced photoacoustic streaming). The controls were irrigated with distilled water and conventional needle irrigation. Subsequently, the dentine samples were separated from the model and analysed using a scanning electron microscope (SEM). Fifteen operative fields were scanned per block, and SEM pictures were captured. Two calibrated evaluators examined the images and collected data using a four-degree scale. Nonparametric tests were used to evaluate for statistical significance amongst the groups. The group undergoing laser-activated irrigation using photon-induced photoacoustic streaming exhibited the most favourable results in the removal of biofilm. Passive ultrasonic irrigation scores were significantly lower than both the Endoactivator and needle irrigation scores. Sonic and needle irrigation were not significantly different. The least favourable results were found in the control group. Laser activation of 6% sodium hypochlorite significantly improved the cleaning of biofilm-infected dentine followed by passive ultrasonic irrigation. © 2013 International Endodontic Journal. Published by John Wiley & Sons Ltd.

Modeling the Effects of Irrigation on Land Surface Fluxes and States over the Conterminous United States: Sensitivity to Input Data and Model Parameters

DOE Office of Scientific and Technical Information (OSTI.GOV)

Leng, Guoyong; Huang, Maoyi; Tang, Qiuhong

2013-09-16

Previous studies on irrigation impacts on land surface fluxes/states were mainly conducted as sensitivity experiments, with limited analysis of uncertainties from the input data and model irrigation schemes used. In this study, we calibrated and evaluated the performance of irrigation water use simulated by the Community Land Model version 4 (CLM4) against observations from agriculture census. We investigated the impacts of irrigation on land surface fluxes and states over the conterminous United States (CONUS) and explored possible directions of improvement. Specifically, we found large uncertainty in the irrigation area data from two widely used sources and CLM4 tended to producemore » unrealistically large temporal variations of irrigation demand for applications at the water resources region scale over CONUS. At seasonal to interannual time scales, the effects of irrigation on surface energy partitioning appeared to be large and persistent, and more pronounced in dry than wet years. Even with model calibration to yield overall good agreement with the irrigation amounts from the National Agricultural Statistics Service (NASS), differences between the two irrigation area datasets still dominate the differences in the interannual variability of land surface response to irrigation. Our results suggest that irrigation amount simulated by CLM4 can be improved by (1) calibrating model parameter values to account for regional differences in irrigation demand and (2) accurate representation of the spatial distribution and intensity of irrigated areas.« less

A framework for the definition of standardized protocols for measuring upper-extremity kinematics.

PubMed

Kontaxis, A; Cutti, A G; Johnson, G R; Veeger, H E J

2009-03-01

Increasing interest in upper extremity biomechanics has led to closer investigations of both segment movements and detailed joint motion. Unfortunately, conceptual and practical differences in the motion analysis protocols used up to date reduce compatibility for post data and cross validation analysis and so weaken the body of knowledge. This difficulty highlights a need for standardised protocols, each addressing a set of questions of comparable content. The aim of this work is therefore to open a discussion and propose a flexible framework to support: (1) the definition of standardised protocols, (2) a standardised description of these protocols, and (3) the formulation of general recommendations. Proposal of a framework for the definition of standardized protocols. The framework is composed by two nested flowcharts. The first defines what a motion analysis protocol is by pointing out its role in a motion analysis study. The second flowchart describes the steps to build a protocol, which requires decisions on the joints or segments to be investigated and the description of their mechanical equivalent model, the definition of the anatomical or functional coordinate frames, the choice of marker or sensor configuration and the validity of their use, the definition of the activities to be measured and the refinements that can be applied to the final measurements. Finally, general recommendations are proposed for each of the steps based on the current literature, and open issues are highlighted for future investigation and standardisation. Standardisation of motion analysis protocols is urgent. The proposed framework can guide this process through the rationalisation of the approach.

Security of the arbitrated quantum signature protocols revisited

NASA Astrophysics Data System (ADS)

Kejia, Zhang; Dan, Li; Qi, Su

2014-01-01

Recently, much attention has been paid to the study of arbitrated quantum signature (AQS). Among these studies, the cryptanalysis of some AQS protocols and a series of improved ideas have been proposed. Compared with the previous analysis, we present a security criterion, which can judge whether an AQS protocol is able to prevent the receiver (i.e. one participant in the signature protocol) from forging a legal signature. According to our results, it can be seen that most AQS protocols which are based on the Zeng and Keitel (ZK) model are susceptible to a forgery attack. Furthermore, we present an improved idea of the ZK protocol. Finally, some supplement discussions and several interesting topics are provided.

Soil water nitrate and ammonium dynamics under a sewage effluent irrigated eucalypt plantation.

PubMed

Livesley, S J; Adams, M A; Grierson, P F

2007-01-01

Managed forests and plantations are appropriate ecosystems for land-based treatment of effluent, but concerns remain regarding nutrient contamination of ground- and surface waters. Monthly NO3-N and NH4-N concentrations in soil water, accumulated soil N, and gross ammonification and nitrification rates were measured in the second year of a second rotation of an effluent irrigated Eucalyptus globulus plantation in southern Western Australia to investigate the separate and interactive effects of drip and sprinkler irrigation, effluent and water irrigation, irrigation rate, and harvest residues retention. Nitrate concentrations of soil water were greater under effluent irrigation than water irrigation but remained <15 mg L(-1) when irrigated at the normal rate (1.5-2.0 mm d(-1)), and there was little evidence of downward movement. In contrast, NH4-N concentrations of soil water at 30 and 100 cm were generally greater under effluent irrigation than water irrigation when irrigated at the normal rate because of direct effluent NH4-N input and indirect ammonification of soil organic N. Drip irrigation of effluent approximately doubled peak NO3-N and NH4-N concentrations in soil water. Harvest residue retention reduced concentrations of soil water NO3-N at 30 cm during active sprinkler irrigation, but after 1 yr of irrigation there was no significant difference in the amount of N stored in the soil system, although harvest residue retention did enhance the "nitrate flush" in the following spring. Gross mineralization rates without irrigation increased with harvest residue retention and further increased with water irrigation. Irrigation with effluent further increased gross nitrification to 3.1 mg N kg(-1) d(-1) when harvest residues were retained but had no effect on gross ammonification, which suggested the importance of heterotrophic nitrification. The downward movement of N under effluent irrigation was dominated by NH4-N rather than NO3-N. Improving the capacity of forest soils to store and transform N inputs through organic matter management must consider the dynamic equilibrium between N input, uptake, and immobilization according to soil C status, and the effect changing microbial processes and environmental conditions can have on this equilibrium.

Effects of partial root-zone irrigation on hydraulic conductivity in the soil–root system of maize plants

PubMed Central

Hu, Tiantian; Kang, Shaozhong; Li, Fusheng; Zhang, Jianhua

2011-01-01

Effects of partial root-zone irrigation (PRI) on the hydraulic conductivity in the soil–root system (Lsr) in different root zones were investigated using a pot experiment. Maize plants were raised in split-root containers and irrigated on both halves of the container (conventional irrigation, CI), on one side only (fixed PRI, FPRI), or alternately on one of two sides (alternate PRI, APRI). Results show that crop water consumption was significantly correlated with Lsr in both the whole and irrigated root zones for all three irrigation methods but not with Lsr in the non-irrigated root zone of FPRI. The total Lsr in the irrigated root zone of two PRIs was increased by 49.0–92.0% compared with that in a half root zone of CI, suggesting that PRI has a significant compensatory effect of root water uptake. For CI, the contribution of Lsr in a half root zone to Lsr in the whole root zone was ∼50%. For FPRI, the Lsr in the irrigated root zone was close to that of the whole root zone. As for APRI, the Lsr in the irrigated root zone was greater than that of the non-irrigated root zone. In comparison, the Lsr in the non-irrigated root zone of APRI was much higher than that in the dried zone of FPRI. The Lsr in both the whole and irrigated root zones was linearly correlated with soil moisture in the irrigated root zone for all three irrigation methods. For the two PRI treatments, total water uptake by plants was largely determined by the soil water in the irrigated root zone. Nevertheless, the non-irrigated root zone under APRI also contributed to part of the total crop water uptake, but the continuously non-irrigated root zone under FPRI gradually ceased to contribute to crop water uptake, suggesting that it is the APRI that can make use of all the root system for water uptake, resulting in higher water use efficiency. PMID:21527627

Growth and Flowering Responses of Cut Chrysanthemum Grown under Restricted Root Volume to Irrigation Frequency

PubMed Central

Taweesak, Viyachai; Lee Abdullah, Thohirah; Hassan, Siti Aishah; Kamarulzaman, Nitty Hirawaty; Wan Yusoff, Wan Abdullah

2014-01-01

Influences of irrigation frequency on the growth and flowering of chrysanthemum grown under restricted root volume were tested. Chrysanthemum cuttings (Chrysanthemum morifolium “Reagan White”) were grown in seedling tray which contained coconut peat in volumes of 73 and 140 cm3. Plants were irrigated with drip irrigation at irrigation frequencies of 4 (266 mL), 6 (400 mL), and 8 (533 mL) times/day to observe their growth and flowering performances. There was interaction between irrigation frequency and substrate volume on plant height of chrysanthemum. Plants grown in 140 cm3 substrates and irrigated 6 times/day produced the tallest plant of 109.25 cm. Plants irrigated 6 and 8 times/day had significantly higher level of phosphorus content in their leaves than those plants irrigated 4 times/day. The total leaf area, number of internodes, leaf length, and leaf width of chrysanthemums grown in 140 cm3 substrate were significantly higher than those grown in 73 cm3 substrate. The numbers of flowers were affected by both irrigation frequencies and substrate volumes. Chrysanthemums irrigated 8 times/day had an average of 19.56 flowers while those irrigated 4 times/day had an average of 16.63 flowers. Increasing irrigation frequency can improve the growth and flowering of chrysanthemums in small substrate volumes. PMID:25478586

Irrigation Induced Surface Cooling in the Context of Modern and Increased Greenhouse Gas Forcing

NASA Technical Reports Server (NTRS)

Cook, Benjamin I.; Puma, Michael J.; Krakauer, Nir Y.

2010-01-01

There is evidence that expected warming trends from increased greenhouse gas (GHG) forcing have been locally masked by irrigation induced cooling, and it is uncertain how the magnitude of this irrigation masking effect will change in the future. Using an irrigation dataset integrated into a global general circulation model, we investigate the equilibrium magnitude of irrigation induced cooling under modern (Year 2000) and increased (A1B Scenario, Year 2050) GHG forcing, using modern irrigation rates in both scenarios. For the modern scenario, the cooling is largest over North America, India, the Middle East, and East Asia. Under increased GHG forcing, this cooling effect largely disappears over North America, remains relatively unchanged over India, and intensifies over parts of China and the Middle East. For North America, irrigation significantly increases precipitation under modern GHG forcing; this precipitation enhancement largely disappears under A1B forcing, reducing total latent heat fluxes and the overall irrigation cooling effect. Over India, irrigation rates are high enough to keep pace with increased evaporative demand from the increased GHG forcing and the magnitude of the cooling is maintained. Over China, GHG forcing reduces precipitation and shifts the region to a drier evaporative regime, leading to a relatively increased impact of additional water from irrigation on the surface energy balance. Irrigation enhances precipitation in the Middle East under increased GHG forcing, increasing total latent heat fluxes and enhancing the irrigation cooling effect. Ultimately, the extent to which irrigation will continue to compensate for the warming from increased GHG forcing will primarily depend on changes in the background evaporative regime, secondary irrigation effects (e.g. clouds, precipitation), and the ability of societies to maintain (or increase) current irrigation rates.

Dissemination of sustainable irrigation strategies for almond and olive orchards via a participatory approach. Project LIFE+IRRIMAN

NASA Astrophysics Data System (ADS)

Garcia-Vila, Margarita; Gamero-Ojeda, Pablo; Ascension Carmona, Maria; Berlanga, Jose; Fereres, Elias

2017-04-01

Dissemination of sustainable irrigation strategies for almond and olive orchards via a participatory approach. Project LIFE+IRRIMAN Spain is the world's first and third largest producer of olive oil and almond, respectively. Despite huge efforts in the last years by the production sector towards intensification, cultural issues relative to the traditional rain-fed crop management know how, prevent farmers from adoption of sustainable irrigation management practices. Consequently, even though there has been progress in irrigation management research for these two crops, adoption of modern irrigation techniques by farmers has been slow. Sustainable irrigation strategies for olive and almond orchards are being designed, implemented, validated and disseminated under the framework of the LIFE+ IRRIMAN project, through a participatory approach. The implementation of the LIFE+ IRRIMAN innovative and demonstrative actions has been carried out in an irrigation district of Southern Spain (Genil-Cabra Irrigation Scheme, Andalusia). The approach designed has four phases: i) design and implementation of sustainable irrigation strategies in demonstration farms; ii) dissemination of best irrigation practices which were tested in the initial year throughout the irrigation scheme by the irrigation advisory service; iii) assessment of degree of adoption and re-design of the dissemination strategies; and, iv) based on the results obtained, elaboration of sustainable irrigation guidelines for knowledge transfer in the district at regional and national levels to promote changes in irrigation practices. Participatory approaches have proven to be effective tools for successful irrigation strategies design and diffusion, especially in traditional rain fed crops such as olive and almond trees in the Mediterranean countries. Acknowledgements This work has been funded by the European Union LIFE+ project IRRIMAN (LIFE13 ENV/ES/000539).

Small-Scale Surface (Tank) Irrigation in Asia

NASA Astrophysics Data System (ADS)

Palanisami, K.; Easter, K. William

1987-05-01

Tank irrigation is an ancient tradition in Asia which is now being reviewed as a potential model for future irrigation expansion. South India has thousands of tanks which are in need of rehabilitation after being in operation for over a century. This study evaluates tank irrigation in an area of south India which has the greatest concentration of tanks. Constraints and unique characteristics of tank irrigation are analyzed to provide a basis for devising strategies for improving tank irrigation. A combination of public and private investments along with institutional changes are recommended to help farmers organize to improve irrigation. Yet, only if public investment is carefully integrated with existing private efforts will farmers have incentives to maintain the irrigation systems.

Assessment of irrigation performance: contribution to improve water management in a small catchment in the Brazilian savannas

NASA Astrophysics Data System (ADS)

Rodrigues, Lineu; Marioti, Juliana; Steenhuis, Tammo; Wallender, Wesley

2010-05-01

Irrigated agriculture is the major consumer of surface water in Brazil using over 70% of the total supply. Due to the growing competition for water among different sectors of the economy, sustainable water use can only be achieved by decreasing the portion of water used by the irrigated agriculture. Thus, in order to maintain yield, farmers need to irrigate more efficiently. There is little known on irrigation efficiency in Brazil. Therefore a study was carried out in the Buriti Vermelho basin to assess the irrigation performance of existing system. The experimental basin has a drainage area of 940 hectares and is located in the eastern part of the Federal District, in the Brazilian savanna region. Agriculture is the main activity. There is a dominance of red latosols. Several types of land use and crop cover are encountered in the basin. Conflicts among farmers for water are increasing. As water, in quality and quantity, is crucial to maintain the livelihood of the population in the basin, concern about risk of water lack due to climatic and land use change is in place. Once irrigation is the main water user in the basin, to increase water availability and reduce conflicts a water resource management plan has to be established. For this purpose, irrigation system performance has to be understood. The objective of this work was to assess the performance and the management of irrigation (small and big) that has been carried out by farmers in the Buriti Vermelho experimental watershed. A survey undertaken in 2007 was used to identify the irrigation systems in the basin. It was verified that irrigation is practiced by both small (area up to 6 hectare) and big farmers. Small farmers usually crop limes and vegetables and use micro-irrigation, drip, sprinkler, guns or furrow to irrigate them. Big farmers plant annual crops and use center pivot as irrigation system. In this first assessment 13 irrigation systems were evaluated: five conventional sprinklers, four drip systems, one microirrigation system and three center pivots schemes. Field evaluations used the method advocated by Keller and Bliesner and conducted during farmer scheduled irrigation. Soil samples were taken before irrigations to investigate adequacy of water applied. Since the irrigation water management and the uniformity of water distribution are the two major factors used to define the quality of irrigation, the following criteria for uniformity was used: i) Localized irrigations (distribution uniformity - UD) - excellent (90% < UD), acceptable (70% < UD < 90%), not acceptable (UD < 70); ii) Center pivots and conventional sprinkler irrigations (Christiansen coefficient - UC) - excellent (85% < UC), acceptable (85% < UC < 75%), not acceptable (UC < 75%). The water stored in the root zone after an irrigation event was compared with the real necessity. The results showed that: i) Localized irrigations - Three systems had UD < 70% and all systems presented deficit or excess of irrigation; ii) Conventional sprinkler system - Three system had UD smaller than 75% and all systems applied less water than the minimum necessary to keep an amount of water in the soil that don't cause plant stress; iii) Center pivot - In two system were observed UC < 75%. In one of the center pivots the depth applied was about 42% higher than the required and in the other two it was 39% and 47% lower. The study demonstrated the importance of adopting irrigation management criteria, in agricultural basins, once irrigation water becomes limiting and reduces basin water productivity.

Evaluation of groundwater quality and its suitability for drinking and agricultural use in Thanjavur city, Tamil Nadu, India.

PubMed

Nagarajan, R; Rajmohan, N; Mahendran, U; Senthamilkumar, S

2010-12-01

As groundwater is a vital source of water for domestic and agricultural activities in Thanjavur city due to lack of surface water resources, groundwater quality and its suitability for drinking and agricultural usage were evaluated. In this study, 102 groundwater samples were collected from dug wells and bore wells during March 2008 and analyzed for pH, electrical conductivity, temperature, major ions, and nitrate. Results suggest that, in 90% of groundwater samples, sodium and chloride are predominant cation and anion, respectively, and NaCl and CaMgCl are major water types in the study area. The groundwater quality in the study site is impaired by surface contamination sources, mineral dissolution, ion exchange, and evaporation. Nitrate, chloride, and sulfate concentrations strongly express the impact of surface contamination sources such as agricultural and domestic activities, on groundwater quality, and 13% of samples have elevated nitrate content (>45 mg/l as NO(3)). PHREEQC code and Gibbs plots were employed to evaluate the contribution of mineral dissolution and suggest that mineral dissolution, especially carbonate minerals, regulates water chemistry. Groundwater suitability for drinking usage was evaluated by the World Health Organization and Indian standards and suggests that 34% of samples are not suitable for drinking. Integrated groundwater suitability map for drinking purposes was created using drinking water standards based on a concept that if the groundwater sample exceeds any one of the standards, it is not suitable for drinking. This map illustrates that wells in zones 1, 2, 3, and 4 are not fit for drinking purpose. Likewise, irrigational suitability of groundwater in the study region was evaluated, and results suggest that 20% samples are not fit for irrigation. Groundwater suitability map for irrigation was also produced based on salinity and sodium hazards and denotes that wells mostly situated in zones 2 and 3 are not suitable for irrigation. Both integrated suitability maps for drinking and irrigation usage provide overall scenario about the groundwater quality in the study area. Finally, the study concluded that groundwater quality is impaired by man-made activities, and proper management plan is necessary to protect valuable groundwater resources in Thanjavur city.

Estimate of uptake and translocation of emerging organic contaminants from irrigation water concentration in lettuce grown under controlled conditions.

PubMed

Hurtado, Carlos; Domínguez, Carmen; Pérez-Babace, Lorea; Cañameras, Núria; Comas, Jordi; Bayona, Josep M

2016-03-15

The widespread distribution of emerging organic contaminants (EOCs) in the water cycle can lead to their incorporation in irrigated crops, posing a potential risk for human consumption. To gain further insight into the processes controlling the uptake of organic microcontaminants, Batavia lettuce (Lactuca sativa) grown under controlled conditions was watered with EOCs (e.g., non-steroidal anti-inflammatories, sulfonamides, β-blockers, phenolic estrogens, anticonvulsants, stimulants, polycyclic musks, biocides) at different concentrations (0-40μgL(-1)). Linear correlations were obtained between the EOC concentrations in the roots and leaves and the watering concentrations for most of the contaminants investigated. However, large differences were found in the root concentration factors ( [Formula: see text] =0.27-733) and leaf translocation concentration factors ( [Formula: see text] =0-3) depending on the persistence of the target contaminants in the rhizosphere and the specific physicochemical properties of each one. With the obtained dataset, a simple predictive model based on a linear regression and the root bioconcentration and translocation factors can be used to estimate the concentration of the target EOCs in leaves based on the dose supplied in the irrigation water or the soil concentration. Finally, enantiomeric fractionation of racemic ibuprofen from the initial spiking mixture suggests that biodegradation mainly occurs in the rhizosphere. Copyright © 2015 Elsevier B.V. All rights reserved.

The effect of Sphagnum farming on the greenhouse gas balance of donor and propagation areas, irrigation polders and commercial cultivation sites

NASA Astrophysics Data System (ADS)

Oestmann, Jan; Tiemeyer, Bärbel

2017-04-01

Drainage of peatlands for agriculture, forestry and peat extraction turned these landscapes into hotspots of greenhouse gas emissions. Climate protection now fosters rewetting projects to restore the natural peatland function as a sink of atmospheric carbon. One possible way to combine ecological and economical goals is Sphagnum farming, i.e. the cultivation of Sphagnum mosses as high-quality substrates for horticulture. This project scientifically evaluates the attempt of commercial Sphagnum farming on former peat extraction sites in north-western Germany. The exchange of carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) of the whole peatland-based production chain comprising a donor mire, a propagation area, an irrigation polder and a cultivation site will be determined in a high temporal resolution for two years using manual chambers. This will allow evaluating the greenhouse gas balance of Sphagnum farming sites in comparison to near-natural sites and the potential of Sphagnum farming for restoring drained peatlands to sinks of atmospheric carbon. The influence of different irrigation techniques will also be tested. Additionally, selected plots will be equipped with open top chambers in order to examine the greenhouse gas exchange under potential future climate change conditions. Finally, a 13C pulse labeling experiment will make it possible to trace the newly sequestered CO2 in biomass, soil, respiration and dissolved organic carbon.

Creating wealth from groundwater for dollar-a-day farmers: Where the silent revolution and the four revolutions to end rural poverty meet

NASA Astrophysics Data System (ADS)

Polak, Paul; Yoder, Robert

2006-03-01

More than 550 million of the current 1.1 billion people earning less than 1-a-day earn a living from agriculture in developing countries. A revolution in water control is needed to develop and mass-disseminate new, affordable, small-plot irrigation technologies. A revolution in agriculture is required to enable smallholders to produce high-value, marketable, labor-intensive cash crops. A revolution in markets is needed to open access to markets for the crops they produce and the inputs they need to produce them. Finally, a revolution in design, based on the ruthless pursuit of affordability, is needed to harness shallow groundwater. The experiences of suppliers of treadle pumps, low-cost drip irrigation and water storage systems were examined. The wealth these technologies generated, coupled with falling prices for small diesel pumps in countries like India and China, created a suitable environment for the rapid adoption of affordable diesel pump tubewells, which in turn created vigorous water markets and expanded access to affordable irrigation water for smallholders. The combination of smallholder-centered revolutions, along with the ‘silent revolution in groundwater’ described by Llamas and Martinez-Santos (Water Sci Technol 51(8):167-174, 2005) provide new practical options for meeting the UN Millennium Development Goals on poverty and hunger by 2015.

Microbiological quality of a waste stabilization pond effluent used for restricted irrigation in Valle Del Cauca, Colombia.

PubMed

Madera, C A; Peña, M R; Mara, D D

2002-01-01

This paper discusses the applicability of effluent reuse in agriculture after treatment in a series of anaerobic, facultative and maturation ponds. The WSP system is located in Ginebra municipality, a small town in southwest Colombia. The total HRT is 12 days. Several samples of the final effluent were taken over a 55 day period and were analysed for E. coli, Streptococcus spp. and helminth eggs. Some additional grab samples were taken to determine the presence of pathogenic bacteria such as Salmonella spp. and Shigella spp. The results showed that the system was able to remove 4 log units of E. coli, 1 log unit of Streptococcus spp. and 100% of helminth eggs. Meanwhile, Salmonella spp. were detected in the effluent of the facultative pond whilst Shigella spp. were not detected in any sample. The main species of helminth eggs encountered were Taenia spp., Ascaris spp., Trichuris spp., Hymenolepis nana, H. diminuta and Enterobius vermicularis. Removal efficiencies were satisfactory despite the relatively short HRT. Nevertheless, WHO guidelines were slightly surpassed in the case of E. coli for unrestricted irrigation. The helminth egg value was always below the maximum WHO limit. Hence, this effluent can be safely used for restricted irrigation provided that field workers are protected from direct contact with wastewater given the presence of Salmonella spp. in the facultative pond effluent.

Crop yields response to water pressures in the Ebro basin in Spain: risk and water policy implications

NASA Astrophysics Data System (ADS)

Quiroga, S.; Fernández-Haddad, Z.; Iglesias, A.

2011-02-01

The increasing pressure on water systems in the Mediterranean enhances existing water conflicts and threatens water supply for agriculture. In this context, one of the main priorities for agricultural research and public policy is the adaptation of crop yields to water pressures. This paper focuses on the evaluation of hydrological risk and water policy implications for food production. Our methodological approach includes four steps. For the first step, we estimate the impacts of rainfall and irrigation water on crop yields. However, this study is not limited to general crop production functions since it also considers the linkages between those economic and biophysical aspects which may have an important effect on crop productivity. We use statistical models of yield response to address how hydrological variables affect the yield of the main Mediterranean crops in the Ebro river basin. In the second step, this study takes into consideration the effects of those interactions and analyzes gross value added sensitivity to crop production changes. We then use Montecarlo simulations to characterize crop yield risk to water variability. Finally we evaluate some policy scenarios with irrigated area adjustments that could cope in a context of increased water scarcity. A substantial decrease in irrigated land, of up to 30% of total, results in only moderate losses of crop productivity. The response is crop and region specific and may serve to prioritise adaptation strategies.

Risk of water scarcity and water policy implications for crop production in the Ebro Basin in Spain

NASA Astrophysics Data System (ADS)

Quiroga, S.; Fernández-Haddad, Z.; Iglesias, A.

2010-08-01

The increasing pressure on water systems in the Mediterranean enhances existing water conflicts and threatens water supply for agriculture. In this context, one of the main priorities for agricultural research and public policy is the adaptation of crop yields to water pressures. This paper focuses on the evaluation of hydrological risk and water policy implications for food production. Our methodological approach includes four steps. For the first step, we estimate the impacts of rainfall and irrigation water on crop yields. However, this study is not limited to general crop production functions since it also considers the linkages between those economic and biophysical aspects which may have an important effect on crop productivity. We use statistical models of yield response to address how hydrological variables affect the yield of the main Mediterranean crops in the Ebro River Basin. In the second step, this study takes into consideration the effects of those interactions and analyzes gross value added sensitivity to crop production changes. We then use Montecarlo simulations to characterize crop yield risk to water variability. Finally we evaluate some policy scenarios with irrigated area adjustments that could cope in a context of increased water scarcity. A substantial decrease in irrigated land, of up to 30% of total, results in only moderate losses of crop productivity. The response is crop and region specific and may serve to prioritise adaptation strategies.

Online decision support system for surface irrigation management

NASA Astrophysics Data System (ADS)

Wang, Wenchao; Cui, Yuanlai

2017-04-01

Irrigation has played an important role in agricultural production. Irrigation decision support system is developed for irrigation water management, which can raise irrigation efficiency with few added engineering services. An online irrigation decision support system (OIDSS), in consist of in-field sensors and central computer system, is designed for surface irrigation management in large irrigation district. Many functions have acquired in OIDSS, such as data acquisition and detection, real-time irrigation forecast, water allocation decision and irrigation information management. The OIDSS contains four parts: Data acquisition terminals, Web server, Client browser and Communication system. Data acquisition terminals are designed to measure paddy water level, soil water content in dry land, ponds water level, underground water level, and canals water level. A web server is responsible for collecting meteorological data, weather forecast data, the real-time field data, and manager's feedback data. Water allocation decisions are made in the web server. Client browser is responsible for friendly displaying, interacting with managers, and collecting managers' irrigation intention. Communication system includes internet and the GPRS network used by monitoring stations. The OIDSS's model is based on water balance approach for both lowland paddy and upland crops. Considering basic database of different crops water demands in the whole growth stages and irrigation system engineering information, the OIDSS can make efficient decision of water allocation with the help of real-time field water detection and weather forecast. This system uses technical methods to reduce requirements of user's specialized knowledge and can also take user's managerial experience into account. As the system is developed by the Browser/Server model, it is possible to make full use of the internet resources, to facilitate users at any place where internet exists. The OIDSS has been applied in Zhanghe Irrigation District (Center China) to manage the required irrigation deliveries. Two years' application indicates that the proposed OIDSS can achieve promising performance for surface irrigation. Historical data of rice growing period in 2014 has been applied to test the OIDSS: it gives out 3 irrigation decisions, which is consistent with actual irrigation times and the forecast irrigation dates are well fit with the actual situations; the corresponding amount of total irrigation decreases by 15.13% compared to those without using the OIDSS.

Colonic irrigation for defecation disorders after dynamic graciloplasty

PubMed Central

Koch, Sacha M.; Uludağ, Özenç; El Naggar, Kadri; van Gemert, Wim G.

2007-01-01

Background and aims Dynamic graciloplasty (DGP) improves anal continence and quality of life for most patients. However, in some patients, DGP fails and fecal incontinence is unsolved or only partially improved. Constipation is also a significant problem after DGP, occurring in 13–90%. Colonic irrigation can be considered as an additional or salvage treatment for defecation disorders after unsuccessful or partially successful DGP. In this study, the effectiveness of colonic irrigation for the treatment of persistent fecal incontinence and/or constipation after DGP is investigated. Materials and methods Patients with defecation disorders after DGP visiting the outpatient clinic of the University Hospital Maastricht were selected for colonic irrigation as additional therapy or salvage therapy in the period between January 1999 and June 2003. The Biotrol® Irrimatic pump or the irrigation bag was used for colonic irrigation. Relevant physical and medical history was collected. The patients were asked to fill out a detailed questionnaire about colonic irrigation. Results Forty-six patients were included in the study with a mean age of 59.3 ± 12.4 years (80% female). On average, the patients started the irrigation 21.39 ± 38.77 months after the DGP. Eight patients started irrigation before the DGP. Fifty-two percent of the patients used the irrigation as additional therapy for fecal incontinence, 24% for constipation, and 24% for both. Irrigation was usually performed in the morning. The mean frequency of irrigation was 0.90 ± 0.40 times per day. The mean amount of water used for the irrigation was 2.27 ± 1.75 l with a mean duration of 39 ± 23 min. Four patients performed antegrade irrigation through a colostomy or appendicostomy, with good results. Overall, 81% of the patients were satisfied with the irrigation. Thirty-seven percent of the patients with fecal incontinence reached (pseudo-)continence, and in 30% of the patients, the constipation completely resolved. Side effects of the irrigation were reported in 61% of the patients: leakage of water after irrigation, abdominal cramps, and distended abdomen. Seven (16%) patients stopped the rectal irrigation. Conclusion Colonic irrigation is an effective alternative for the treatment of persistent fecal incontinence after DGP and/or recurrent or onset constipation additional to unsuccessful or (partially) successful DGP. PMID:17896111

Two Challenges for U.S. Irrigation Due to Climate Change: Increasing Irrigated Area in Wet States and Increasing Irrigation Rates in Dry States

PubMed Central

McDonald, Robert I.; Girvetz, Evan H.

2013-01-01

Agricultural irrigation practices will likely be affected by climate change. In this paper, we use a statistical model relating observed water use by U.S. producers to the moisture deficit, and then use this statistical model to project climate changes impact on both the fraction of agricultural land irrigated and the irrigation rate (m3ha−1). Data on water withdrawals for US states (1985–2005) show that both quantities are highly positively correlated with moisture deficit (precipitation – PET). If current trends hold, climate change would increase agricultural demand for irrigation in 2090 by 4.5–21.9 million ha (B1 scenario demand: 4.5–8.7 million ha, A2 scenario demand: 9.1–21.9 million ha). Much of this new irrigated area would occur in states that currently have a wet climate and a small fraction of their agricultural land currently irrigated, posing a challenge to policymakers in states with less experience with strict regulation of agriculture water use. Moreover, most of this expansion will occur in states where current agricultural production has relatively low market value per hectare, which may make installation of irrigation uneconomical without significant changes in crops or practices by producers. Without significant increases in irrigation efficiency, climate change would also increase the average irrigation rate from 7,963 to 8,400–10,415 m3ha−1 (B1 rate: 8,400–9,145 m3ha−1, A2 rate: 9,380–10,415 m3ha−1). The irrigation rate will increase the most in states that already have dry climates and large irrigation rates, posing a challenge for water supply systems in these states. Accounting for both the increase in irrigated area and irrigation rate, total withdrawals might increase by 47.7–283.4 billion m3 (B1 withdrawal: 47.7–106.0 billion m3, A2 withdrawal: 117.4–283.4 billion m3). Increases in irrigation water-use efficiency, particularly by reducing the prevalence of surface irrigation, could eliminate the increase in total irrigation withdrawals in many states. PMID:23755255

Irrigation dynamics associated with positive pressure, apical negative pressure and passive ultrasonic irrigations: a computational fluid dynamics analysis.

PubMed

Chen, José Enrique; Nurbakhsh, Babak; Layton, Gillian; Bussmann, Markus; Kishen, Anil

2014-08-01

Complexities in root canal anatomy and surface adherent biofilm structures remain as challenges in endodontic disinfection. The ability of an irrigant to penetrate into the apical region of a canal, along with its interaction with the root canal walls, will aid in endodontic disinfection. The aim of this study was to qualitatively examine the irrigation dynamics of syringe irrigation with different needle tip designs (open-ended and closed-ended), apical negative pressure irrigation with the EndoVac® system, and passive ultrasonic-assisted irrigation, using a computational fluid dynamics model. Syringe-based irrigation with a side-vented needle showed a higher wall shear stress than the open-ended but was localised to a small region of the canal wall. The apical negative pressure mode of irrigation generated the lowest wall shear stress, while the passive-ultrasonic irrigation group showed the highest wall shear stress along with the greatest magnitude of velocity. © 2013 The Authors. Australian Endodontic Journal © 2013 Australian Society of Endodontology.

Chapter A6. Section 6.6. Alkalinity and Acid Neutralizing Capacity

USGS Publications Warehouse

Rounds, Stewart A.; Wilde, Franceska D.

2002-01-01

Alkalinity (determined on a filtered sample) and Acid Neutralizing Capacity (ANC) (determined on a whole-water sample) are measures of the ability of a water sample to neutralize strong acid. Alkalinity and ANC provide information on the suitability of water for uses such as irrigation, determining the efficiency of wastewater processes, determining the presence of contamination by anthropogenic wastes, and maintaining ecosystem health. In addition, alkalinity is used to gain insights on the chemical evolution of an aqueous system. This section of the National Field Manual (NFM) describes the USGS field protocols for alkalinity/ANC determination using either the inflection-point or Gran function plot methods, including calculation of carbonate species, and provides guidance on equipment selection.

Modeling irrigation behavior in groundwater systems

NASA Astrophysics Data System (ADS)

Foster, Timothy; Brozović, Nicholas; Butler, Adrian P.

2014-08-01

Integrated hydro-economic models have been widely applied to water management problems in regions of intensive groundwater-fed irrigation. However, policy interpretations may be limited as most existing models do not explicitly consider two important aspects of observed irrigation decision making, namely the limits on instantaneous irrigation rates imposed by well yield and the intraseasonal structure of irrigation planning. We develop a new modeling approach for determining irrigation demand that is based on observed farmer behavior and captures the impacts on production and water use of both well yield and climate. Through a case study of irrigated corn production in the Texas High Plains region of the United States we predict optimal irrigation strategies under variable levels of groundwater supply, and assess the limits of existing models for predicting land and groundwater use decisions by farmers. Our results show that irrigation behavior exhibits complex nonlinear responses to changes in groundwater availability. Declining well yields induce large reductions in the optimal size of irrigated area and irrigation use as constraints on instantaneous application rates limit the ability to maintain sufficient soil moisture to avoid negative impacts on crop yield. We demonstrate that this important behavioral response to limited groundwater availability is not captured by existing modeling approaches, which therefore may be unreliable predictors of irrigation demand, agricultural profitability, and resilience to climate change and aquifer depletion.

Modeled effects of irrigation on surface climate in the Heihe River Basin, Northwest China

NASA Astrophysics Data System (ADS)

Zhang, Xuezhen; Xiong, Zhe; Tang, Qiuhong

2017-08-01

In Northwest China, water originates from the mountain area and is largely used for irrigation agriculture in the middle reaches. This study investigates the local and remote impact of irrigation on regional climate in the Heihe River Basin, the second largest inland river basin in Northwest China. An irrigation scheme was developed and incorporated into the Weather Research and Forecasting (WRF) model with the Noah-MP land surface scheme (WRF/Noah-MP). The effects of irrigation is assessed by comparing the model simulations with and without consideration of irrigation (hereafter, IRRG and NATU simulations, respectively) for five growth seasons (May to September) from 2009 to 2013. As consequences of irrigation, daily mean temperature decreased by 1.7°C and humidity increased by 2.3 g kg-1 (corresponding to 38.5%) over irrigated area. The temperature and humidity of IRRG simulation matched well with the observations, whereas NATU simulation overestimated temperature and underestimated humidity over irrigated area. The effects on temperature and humidity are generally small outside the irrigated area. The cooling and wetting effects have opposing impacts on convective precipitation, resulting in a negligible change in localized precipitation over irrigated area. However, irrigation may induce water vapor convergence and enhance precipitation remotely in the southeastern portion of the Heihe River Basin.

Impact of irrigation over India on the land surface fluxes

NASA Astrophysics Data System (ADS)

de Rosnay, P. R.; Polcher, J. P.; Laval, K. L.; Sabre, M. S.

2003-04-01

Irrigation is the main water user in the world with 87 % of the global water consumption being attributed to use on irrigated crop land. There are large spatial variations of the irrigated areas, from 68 % in Asia and 16 % in America, 10 % in Europe and the remaining in Africa and Australia. India is the most important irrigating country in the world with a gross irrigation requirement estimated by the FAO at 457 cubic km by year. The environmental impacts of irrigation are very important: irrigation causes the soil salinization, it affects the water quality and ecology, and increases the incidence of water related diseases. Irrigation is also expected to affect the the land surface energy budget, and thereby the climate system. The work presented here is conducted in the framework of the PROMISE European project. It aims to analyze the sensitivity of the land surface fluxes to the intensive irrigation over Indian peninsula. Numerical experiments are conducted with the land surface scheme ORCHIDEE of the Laboratoire de Meteorologie Dynamique, with a 1 degree spatial resolution. Two 2years simulations, forced by the ISLSCP (1987-88) data sets, are compared, with and without irrigation. The analysis focuses on the effect of land irrigation on the surface fluxes (partition of energy between latent and sensible fluxes), and the river flow.

Inhibition of tomato shoot growth by over-irrigation is linked to nitrogen deficiency and ethylene.

PubMed

Fiebig, Antje; Dodd, Ian C

2016-01-01

Although physiological effects of acute flooding have been well studied, chronic effects of suboptimal soil aeration caused by over-irrigation of containerized plants have not, despite its likely commercial significance. By automatically scheduling irrigation according to soil moisture thresholds, effects of over-irrigation on soil properties (oxygen concentration, temperature and moisture), leaf growth, gas exchange, phytohormone [abscisic acid (ABA) and ethylene] relations and nutrient status of tomato (Solanum lycopersicum Mill. cv. Ailsa Craig) were studied. Over-irrigation slowly increased soil moisture and decreased soil oxygen concentration by 4%. Soil temperature was approximately 1°C lower in the over-irrigated substrate. Over-irrigating tomato plants for 2 weeks significantly reduced shoot height (by 25%) and fresh weight and total leaf area (by 60-70%) compared with well-drained plants. Over-irrigation did not alter stomatal conductance, leaf water potential or foliar ABA concentrations, suggesting that growth inhibition was not hydraulically regulated or dependent on stomatal closure or changes in ABA. However, over-irrigation significantly increased foliar ethylene emission. Ethylene seemed to inhibit growth, as the partially ethylene-insensitive genotype Never ripe (Nr) was much less sensitive to over-irrigation than the wild type. Over-irrigation induced significant foliar nitrogen deficiency and daily supplementation of small volumes of 10 mM Ca(NO3 )2 to over-irrigated soil restored foliar nitrogen concentrations, ethylene emission and shoot fresh weight of over-irrigated plants to control levels. Thus reduced nitrogen uptake plays an important role in inhibiting growth of over-irrigated plants, in part by stimulating foliar ethylene emission. © 2015 Scandinavian Plant Physiology Society.

Global rain-fed, irrigated, and paddy croplands: A new high resolution map derived from remote sensing, crop inventories and climate data

NASA Astrophysics Data System (ADS)

Salmon, J. Meghan; Friedl, Mark A.; Frolking, Steve; Wisser, Dominik; Douglas, Ellen M.

2015-06-01

Irrigation accounts for 70% of global water use by humans and 33-40% of global food production comes from irrigated croplands. Accurate and timely information related to global irrigation is therefore needed to manage increasingly scarce water resources and to improve food security in the face of yield gaps, climate change and extreme events such as droughts, floods, and heat waves. Unfortunately, this information is not available for many regions of the world. This study aims to improve characterization of global rain-fed, irrigated and paddy croplands by integrating information from national and sub-national surveys, remote sensing, and gridded climate data sets. To achieve this goal, we used supervised classification of remote sensing, climate, and agricultural inventory data to generate a global map of irrigated, rain-fed, and paddy croplands. We estimate that 314 million hectares (Mha) worldwide were irrigated circa 2005. This includes 66 Mha of irrigated paddy cropland and 249 Mha of irrigated non-paddy cropland. Additionally, we estimate that 1047 Mha of cropland are managed under rain-fed conditions, including 63 Mha of rain-fed paddy cropland and 985 Mha of rain-fed non-paddy cropland. More generally, our results show that global mapping of irrigated, rain-fed, and paddy croplands is possible by combining information from multiple data sources. However, regions with rapidly changing irrigation or complex mixtures of irrigated and non-irrigated crops present significant challenges and require more and better data to support high quality mapping of irrigation.

Predicting deep percolation with eddy covariance under mulch drip irrigation

NASA Astrophysics Data System (ADS)

Ming, Guanghui; Tian, Fuqiang; Hu, Hongchang

2016-04-01

Water is essential for the agricultural development and ecological sustainability of the arid and semi-arid oasis with rare precipitation input and high evaporation demand. Deep percolation (DP) defined as excess irrigation water percolating below the plant root zone will reduce irrigation water use efficiency (WUE). But the DP was often ignored in mulch drip irrigation (MDI) which has reached the area of 1.6 million hectares in Xinjiang, the northwest of China. In this study DP experiments were conducted at an agricultural experiment station located within an irrigation district in the Tarim River Basin for four cotton growing periods. First it was detected the irrigation water infiltrated into the soil layers below 100cm and the groundwater level responded to the irrigation events well. Then DP below 100cm soil layers was calculated using the soil water balance method with the aid of eddy covariance (with the energy balance closure of 0.72). The negative DP (groundwater contribution to the crop-water use through capillary rising) at the seedling and harvesting stages can reach 77mm and has a good negative correlation with the groundwater level and positive correlation with potential evaporation. During the drip irrigation stage approximately 45% of the irrigation became DP and resulted in the low irrigation WUE of 0.6. The DP can be 164mm to 270mm per year which was positive linearly correlated to irrigation depth and negative linear correlated to irrigation interval. It is better to establish the irrigation schedule with small irrigation depth and given frequently to reduce deep percolation and meet crop needs.

Optimization of irrigation scheduling for spring wheat with mulching and limited irrigation water in an arid climate

NASA Astrophysics Data System (ADS)

Wen, Y.

2017-12-01

Combining mulch and irrigation scheduling may lead to an increase of crop yield and water use efficiency (WUE = crop yield/evapotranspiration) with limited irrigation water, especially in arid regions. Based on 2 years' field experiments with ten irrigation-mulching treatments of spring wheat (Triticum aestivum L.) in the Shiyang River Basin Experiment Station in Gansu Province of Northwest China, a simulation-based optimization model for deficit irrigation scheduling of plastic mulching spring wheat was used to analyze an optimal irrigation scheduling for different deficit irrigation scenarios. Results revealed that mulching may increase maximum grain yield without water stress by 0.4-0.6 t ha-1 in different years and WUE by 0.2-0.3 kg m-3 for different irrigation amounts compared with no mulching. Yield of plastic mulching spring wheat was more sensitive to water stress in the early and development growth stages with an increase of cumulative crop water sensitive index (CCWSI) by 42%, and less sensitive to water stress in the mid and late growth stages with a reduction of CCWSI by 24%. For a relative wet year, when irrigation water is only applied once it should be at the mid to end of booting growth stage. Two irrigations should be applied at the beginning of booting and heading growth stages. The irrigation date can be extended to the beginning of jointing and grain formation growth stages with more water available for irrigation. For a normal or a dry year, the first irrigation should be applied 5-8 days earlier than the wet year. The highest WUE of 3.6 kg m-3 was achieved with 180 mm of irrigation applied twice for mulching in a wet year. Combining mulch and an optimal deficit irrigation scheduling is an effective way to increase crop yield and WUE in arid regions.

Soil management and conservation: Irrigation: Methods

USDA-ARS?s Scientific Manuscript database

Irrigation applies water to soil to improve crop production. The three main methods of irrigation are surface, sprinkler and micro. Surface irrigation is used on 85% of the irrigated land in the world. It generally requires lower capital investment because the soil conveys water within the field, ra...

Automation of irrigation systems to control irrigation applications and crop water use efficiency

USDA-ARS?s Scientific Manuscript database

Agricultural irrigation management to slow water withdrawals from non-replenishing quality water resources is a global endeavor and vital to sustaining irrigated agriculture and dependent rural economies. Research in site-specific irrigation management has shown that water use efficiency, and crop p...

Site-specific variable rate irrigation a means to enhance water use efficiency

USDA-ARS?s Scientific Manuscript database

The majority of irrigated cropland in the US is watered with sprinkler irrigation systems. These systems are inherently more efficient in distributing water than furrow or flood irrigation. Appropriate system design of sprinkler irrigation equipment, application methods, and farming practices (e.g. ...

Site-specific variable rate irrigation as a means to enhance water use efficiency

USDA-ARS?s Scientific Manuscript database

The majority of irrigated cropland in the US is watered with sprinkler irrigation systems. These systems are inherently more efficient in distributing water than furrow or flood irrigation. Appropriate system design of sprinkler irrigation equipment, application methods, and farming practices (e.g. ...

Advances in sprinkler irrigation management

USDA-ARS?s Scientific Manuscript database

Sprinkler irrigation is being increasingly adopted in the US and worldwide because it offers increased crop water productivity over what is possible with gravity irrigation. Most sprinkler irrigation is by center pivot, which is presently used on about 50 and 80 percent of land irrigated in the US a...

Efficient model checking of network authentication protocol based on SPIN

NASA Astrophysics Data System (ADS)

Tan, Zhi-hua; Zhang, Da-fang; Miao, Li; Zhao, Dan

2013-03-01

Model checking is a very useful technique for verifying the network authentication protocols. In order to improve the efficiency of modeling and verification on the protocols with the model checking technology, this paper first proposes a universal formalization description method of the protocol. Combined with the model checker SPIN, the method can expediently verify the properties of the protocol. By some modeling simplified strategies, this paper can model several protocols efficiently, and reduce the states space of the model. Compared with the previous literature, this paper achieves higher degree of automation, and better efficiency of verification. Finally based on the method described in the paper, we model and verify the Privacy and Key Management (PKM) authentication protocol. The experimental results show that the method of model checking is effective, which is useful for the other authentication protocols.

Multi-party quantum key agreement protocol secure against collusion attacks

NASA Astrophysics Data System (ADS)

Wang, Ping; Sun, Zhiwei; Sun, Xiaoqiang

2017-07-01

The fairness of a secure multi-party quantum key agreement (MQKA) protocol requires that all involved parties are entirely peer entities and can equally influence the outcome of the protocol to establish a shared key wherein no one can decide the shared key alone. However, it is found that parts of the existing MQKA protocols are sensitive to collusion attacks, i.e., some of the dishonest participants can collaborate to predetermine the final key without being detected. In this paper, a multi-party QKA protocol resisting collusion attacks is proposed. Different from previous QKA protocol resisting N-1 coconspirators or resisting 1 coconspirators, we investigate the general circle-type MQKA protocol which can be secure against t dishonest participants' cooperation. Here, t < N. We hope the results of the presented paper will be helpful for further research on fair MQKA protocols.

Comparison of three methods of DNA extraction from peripheral blood mononuclear cells and lung fragments of equines.

PubMed

Santos, E M; Paula, J F R; Motta, P M C; Heinemann, M B; Leite, R C; Haddad, J P A; Del Puerto, H L; Reis, J K P

2010-08-17

We compared three different protocols for DNA extraction from horse peripheral blood mononuclear cells (PBMC) and lung fragments, determining average final DNA concentration, purity, percentage of PCR amplification using beta-actin, and cost. Thirty-four samples from PBMC, and 33 samples from lung fragments were submitted to DNA extraction by three different protocols. Protocol A consisted of a phenol-chloroform and isoamylic alcohol extraction, Protocol B used alkaline extraction with NaOH, and Protocol C used the DNAzol((R)) reagent kit. Protocol A was the best option for DNA extraction from lung fragments, producing high DNA concentrations, with high sensitivity in PCR amplification (100%), followed by Protocols C and B. On the other hand, for PBMC samples, Protocol B gave the highest sensitivity in PCR amplification (100%), followed by Protocols C and A. We conclude that Protocol A should be used for PCR diagnosis from lung fragment samples, while Protocol B should be used for PBMC.

New approach to enhance and evaluate the performance of vehicle-infrastructure integration and its communication systems, final report.

DOT National Transportation Integrated Search

2010-09-01

Initial research studied the use of wireless local area networks (WLAN) protocols in Inter-Vehicle Communications : (IVC) environments. The protocols performance was evaluated in terms of measuring throughput, jitter time and : delay time. This re...

77 FR 63757 - Extension of the Commission's Rules Regarding Outage Reporting to Interconnected Voice Over...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-17

... Commission's Rules Regarding Outage Reporting to Interconnected Voice Over Internet Protocol Service Providers and Broadband Internet Service Providers AGENCY: Federal Communications Commission. ACTION: Final... Regarding Outage Reporting to Interconnected Voice Over Internet Protocol Service Providers and Broadband...

A Draft Test Protocol for Detecting Possible Biohazards in Martian Samples Returned to Earth

NASA Technical Reports Server (NTRS)

Rummel, John D. (Editor); Race, Margaret S.; DeVincenzi, Donald L.; Schad, P. Jackson; Stabekis, Pericles D.; Viso, Michel; Acevedo, Sara E.

2002-01-01

This document presents the first complete draft of a protocol for detecting possible biohazards in Mars samples returned to Earth: it is the final product of the Mars Sample Handling Protocol Workshop Series. convened in 2000-2001 by NASA's Planetary Protection Officer. The goal of the five-workshop Series vas to develop a comprehensive protocol by which returned martian sample materials could be assessed k r the presence of any biological hazard(s) while safeguarding the purity of the samples from possible terrestrial contamination.

Drip irrigation research update at NPRL

USDA-ARS?s Scientific Manuscript database

Drip irrigation research has been conducted since 1998 at NPRL. Systems include deep subsurface drip irrigation (SSDI), surface drip irrigation (SDI), and shallow subsurface drip irrigation (S3DI). Results have shown that SDI and S3DI are more economical to install than SSDI. SDI systems have more r...

Impact of irrigation, nitrogen fertilization, and spatial management on maize

USDA-ARS?s Scientific Manuscript database

The spatial management of irrigation water and N fertilization can be employed to reduce interactive effects, thus increasing water and N use efficiency and reducing pollution. Partial root-zone irrigation is a modified form of deficit irrigation which involves irrigating only one part of the root z...

Colostomy irrigation: are we offering it enough?

PubMed

Woodhouse, Fran

This article discusses the use of irrigation for suitable colostomists and reasons why it can have a very positive effect on lifestyle. While it is evidence-based it also includes anecdotal tips from patients who irrigate. The suitability of patients to irrigate and ways to 'get started' with irrigation are discussed.

Does deficit irrigation of field crops increase water use efficiency

USDA-ARS?s Scientific Manuscript database

Deficit irrigation is often proposed as a method to stretch limited irrigation water supply and increase water use efficiency. A field study of field crops in the high plains shows that water use efficiency, in terms of irrigation water applied, often increases with deficit irrigation. However, in t...

Plant, soil and weather based cues for irrigation timing in soybean production 2014

USDA-ARS?s Scientific Manuscript database

Expanded use of irrigation management tools are needed to improve irrigation and water use efficiency in eastern Arkansas soybean production. In 2014 we initiated an Arkansas Soybean Promotion Board supported project to examine irrigation initiation timing on a sandy loam soil in a furrow-irrigated ...

Is small-scale irrigation an efficient pro-poor strategy in the upper Limpopo Basin in Mozambique?

NASA Astrophysics Data System (ADS)

Ducrot, Raphaelle

2017-08-01

In Sub-Saharan Africa, there is evidence that households with access to small-scale irrigation are significantly less poor than households that do not have access to irrigation. However, private motopumps tend to be distributed inequitably. This paper investigates the success of explicit pro-poor interventions with emphasis on small-scale irrigation in the semi-arid Limpopo Basin in Mozambique. It reveals that high irrigation costs are progressively excluding the poor, who are unable to generate a cash income from other activities they need to fund irrigation. In addition, the operation of collective schemes involving the poor is being jeopardized by the development of private irrigation schemes, which benefit from hidden subsidies appropriated by local elites. This results in unequal access to irrigation, which can cause resentment at community level. This weakens community cohesiveness, as well as communities' capacities for collective action and coordination, which are crucial for collective irrigation.

Effects of irrigation on the seasonal abundance of Empoasca vitis in north-Italian vineyards.

PubMed

Fornasiero, D; Duso, C; Pozzebon, A; Tomasi, D; Gaiotti, F; Pavan, F

2012-02-01

The effect of irrigation on the abundance of Empoasca vitis (Göthe) populations was investigated in four vineyards located in northeastern Italy. In two experiments, we compared leafhopper population densities in plots irrigated (micro-spray irrigation system) or nonirrigated. In another experiment, we studied the effect of various irrigation systems on E. vitis populations over two successive seasons. In particular, five treatments were compared: control (not irrigated), traditional drip system, three types of subirrigation varying in distance from the row (40, 135, and 95 cm). In this vineyard, stem water potential was monitored with a pressure chamber. E. vitis population densities were affected by irrigation, with higher densities of this pest recorded on irrigated vines. Highest E. vitis densities were detected in drip irrigation plots compared with nonirrigated plots where water stress was highest. Moderate water stress (subirrigation plots) was associated with intermediate leafhopper densities. Implications for integrated pest management are discussed.

Local irrigation management institutions mediate changes driven by external policy and market pressures in Nepal and Thailand.

PubMed

Bastakoti, Ram C; Shivakoti, Ganesh P; Lebel, Louis

2010-09-01

This article assesses the role of local institutions in managing irrigation water use. Fifty irrigation systems in each country were studied in Nepal and Thailand to compare the influence of local institutions on performance of irrigation systems amid changes in external policy and market pressures. Nepal's new irrigation policy after the re-instatement of multiparty democracy in 1990 emphasized participatory irrigation management transferring the management responsibility from state authorities to water users. The water user associations of traditional farmer-managed irrigation systems were formally recognized by requiring registration with related state authorities. In Thailand also government policies encouraged people's participation in irrigation management. Today water users are directly involved in management of even some large irrigation systems at the level of tertiary canals. Traditional communal irrigation systems in northern Thailand received support for system infrastructure improvement but have faced increased interference from government. In Thailand market development supported diversification in farming practices resulting in increased areas under high water-demanding commercial crops in the dry season. In contrast, the command areas of most irrigation systems in Nepal include cereal-based subsistence farming with only one-third having commercial farming. Cropping intensities are higher in Nepal than in Thailand reflecting, in part, differences in availability of land and management. In both countries local institutions play an important role in maintaining the performance of irrigation systems as external drivers and local contexts change. Local institutions have provided alternative options for irrigation water use by mediating external pressures.

Irrigation efficiency and quality of irrigation return flows in the Ebro River Basin: an overview.

PubMed

Causapé, J; Quílez, D; Aragüés, R

2006-06-01

The review analysis of twenty two irrigation efficiency (IE) studies carried out in the Ebro River Basin shows that IE is low (average IE)(avg)(= 53%) in surface-irrigated areas with high-permeable and shallow soils inadequate for this irrigation system, high (IE)(avg)(= 79%) in surface-irrigated areas with appropriate soils for this system, and very high (IE)(avg)(= 94%) in modern, automated and well managed sprinkler-irrigated areas. The unitary salt (total dissolved solids) and nitrate loads exported in the irrigation return flows (IRF) of seven districts vary, depending on soil salinity and on irrigation and N fertilization management, between 3-16 Mg salt/ha x year and 23-195 kg NO)(3) (-)-N/ha x year, respectively. The lower nitrate loads exported from high IE districts show that a proper irrigation design and management is a key factor to reduce off-site nitrogen pollution. Although high IE's also reduce off-site salt pollution, the presence of salts in the soil or subsoil may induce relatively high salt loads (>or=14 Mg/ha x year) even in high IE districts. Two important constrains identified in our revision were the short duration of most surveys and the lack of standards for conducting irrigation efficiency and mass balance studies at the irrigation district level. These limitations {emphasize the need for the establishment of a permanent and standardized network of drainage monitoring stations for the appropriate off-site pollution diagnosis and control of irrigated agriculture.

Comparison of Irrigation Times Using Gravity and High-Pressure Lavage.

PubMed

Muscatelli, Stefano; Howe, Andrea; O'Hara, Nathan N; O'Toole, Robert V; Sprague, Sheila A; Slobogean, Gerard P

2017-05-01

The benefits of high-pressure pulsatile lavage for open fracture irrigation have been controversial based on conflicting experimental animal research. Recently published data definitively demonstrated that irrigation pressure does not affect the incidence of reoperation for the treatment of open fractures. However, proponents of pulsatile lavage argue a faster irrigation time is an important benefit of the high-pressure treatment. The purpose of this study was to determine the difference in irrigation time between gravity and high-pressure lavage. The experimental setup was designed to mimic clinical practice and compared mean irrigation flow times for high-pressure pulsatile lavage and gravity flow with 2 commonly used tube diameters. Each irrigation setup was tested 5 times at 3 different irrigation bag heights. Analysis of variance and Student's t tests were used to compare the mean flow times of 3 irrigation methods at each height and among the 3 heights for each irrigation method. The mean irrigation flow time in the various experimental models ranged from 161 to 243 seconds. Gravity irrigation with wide tubing was significantly faster than pulsatile lavage or gravity with narrow tubing (P<.001). Increasing irrigation bag height had only a marginal effect on the overall flow times (<9% difference). The difference in mean flow time among the testing techniques was slightly longer than 1 minute, which is unlikely to have a material impact on procedural costs, operating times, and subsequent gains in patient safety. [Orthopedics. 2017; 40(3):e413-e416.]. Copyright 2017, SLACK Incorporated.

Colostomy irrigation: results of 25 cases with particular reference to quality of life.

PubMed

Karadağ, Ayişe; Menteş, B Bülent; Ayaz, Sultan

2005-04-01

The aim of this study was to document our results with colostomy irrigation with particular emphasis on the possible contribution of irrigation on quality of life. Colostomy irrigation is a useful method of achieving faecal continence in selected conditions, and may improve quality of life. When successful, irrigation offers a regular, predictable elimination pattern and only a small covering is needed for security between irrigations. The digestive disease quality of life questionnaire-15 (DDQ-15) and Short Form-36 were used to analyse quality of life before and 12 months after stomatherapy in a series of 25 irrigating patients with permanent end colostomies. During the same time period, 10 similar patients with left-end colostomies who also received counselling but did not consent to colostomy irrigation were also analysed for comparison. Colostomy irrigation was found to be effective for achieving faecal continence in selected patients with end colostomies with no complications or significant side-effects, The digestive disease quality of life questionnaire-15 score improved significantly in both groups after stomatherapy (P < 0.0001 and P = 0.009 in the irrigating and non-irrigating groups respectively). The poststomatherapy digestive disease quality of life questionnaire-15 score of the irrigating group was also significantly higher than that of the non-irrigating group (P = 0.039). Although none of the poststomatherapy item scales of Short Form-36 differed significantly between the two groups, stomatherapy with CI resulted in significant improvements in role limitation due to physical problems, social functioning, role limitation due to emotional problems, general mental health, vitality and bodily pain (P < 0.05 for all comparisons). On the contrary, the non-irrigating patient group showed significant improvements only in social functioning and general mental health. Our findings suggest that colostomy irrigation can be a useful method of achieving faecal continence in selected conditions, it is safe, and it may help improve many aspects of quality of life. Colostomy irrigation is free from complications and significant side-effects, and it may serve as a useful adjunct to conventional stomatherapy. Therefore, the enterostomal therapy nurse should assess the appropriateness of routine irrigation as a method of stoma management for patients with left-end colostomy.

Evaluation of limited irrigation strategies to improve water use efficiency and wheat yield in the North China Plain.

PubMed

Zhang, Di; Li, Ruiqi; Batchelor, William D; Ju, Hui; Li, Yanming

2018-01-01

The North China Plain is one of the most important grain production regions in China, but is facing serious water shortages. To achieve a balance between water use and the need for food self-sufficiency, new water efficient irrigation strategies need to be developed that balance water use with farmer net return. The Crop Environment Resource Synthesis Wheat (CERES-Wheat model) was calibrated and evaluated with two years of data which consisted of 3-4 irrigation treatments, and the model was used to investigate long-term winter wheat productivity and water use from irrigation management in the North China Plain. The calibrated model simulated accurately above-ground biomass, grain yield and evapotranspiration of winter wheat in response to irrigation management. The calibrated model was then run using weather data from 1994-2016 in order to evaluate different irrigation strategies. The simulated results using historical weather data showed that grain yield and water use was sensitive to different irrigation strategies including amounts and dates of irrigation applications. The model simulated the highest yield when irrigation was applied at jointing (T9) in normal and dry rainfall years, and gave the highest simulated yields for irrigation at double ridge (T8) in wet years. A single simulated irrigation at jointing (T9) produced yields that were 88% compared to using a double irrigation treatment at T1 and T9 in wet years, 86% of that in normal years, and 91% of that in dry years. A single irrigation at jointing or double ridge produced higher water use efficiency because it obtained higher evapotranspiration. The simulated farmer irrigation practices produced the highest yield and net income. When the cost of water was taken into account, limited irrigation was found to be more profitable based on assumptions about future water costs. In order to increase farmer income, a subsidy will likely be needed to compensate farmers for yield reductions due to water savings. These results showed that there is a cost to the farmer for water conservation, but limiting irrigation to a single irrigation at jointing would minimize impact on farmer net return in North China Plain.

Seasonal effects of irrigation on land-atmosphere latent heat, sensible heat and carbon fluxes in semi-arid basin

NASA Astrophysics Data System (ADS)

Xie, Zhenghui; Zeng, Yujin

2017-04-01

Irrigation, which constitutes 70% of the total amount of fresh water consumed by the human population, is significantly impacting the land-atmosphere fluxes. In this study, using the improved Community Land Model version 4.5 (CLM 4.5) with an active crop model, two high resolution ( 1 km) simulations investigating the effects of irrigation on Latent Heat (LH), Sensible Heat (SH) and Carbon Fluxes (or net ecosystem exchange, NEE) from land to atmosphere on the Heihe River Basin in northwestern China were conducted using a high-quality irrigation dataset compiled from 1981 to 2013. The model output and measurements from remote sensing demonstrated the capacity and viability of the developed models to reproduce ecological and hydrological processes. The results revealed the effects of irrigation on LH and SH are strongest during summer with a LH increase of 100 W/m2 and a SH decrease of 60 W/m2 over intensely irrigated areas. However, the reactions are much weaker during spring and autumn when there is much less irrigation. When the irrigation rate below 5 mm/day, the LH generally increases, whereas the SH decreases with growing irrigation rates. However, when the irrigation threshold is in excess of 5 mm/day, there is no accrued effect of irrigation on the LH and SH. Irrigation produces opposite effects to the NEE during spring and summer. During the spring, irrigation yields more discharged carbon from the land to the atmosphere, increasing the NEE value by 0.4-0.8 gC/m2/day, while the summer irrigation favors crop fixing of carbon from atmospheric CO2, decreasing the NEE value by 0.8 gC/m2/day. The repercussions of irrigation on land-atmosphere fluxes are not solely linked to the irrigation amount, and other parameters (especially the temperature) also control the effects of irrigation on LH, SH and NEE. The study indicates that how a land surface model with high spatial resolution can represent crop growing and its effects over basin scale.

Uncertainties in modelling the climate impact of irrigation

NASA Astrophysics Data System (ADS)

de Vrese, Philipp; Hagemann, Stefan

2017-11-01

Irrigation-based agriculture constitutes an essential factor for food security as well as fresh water resources and has a distinct impact on regional and global climate. Many issues related to irrigation's climate impact are addressed in studies that apply a wide range of models. These involve substantial uncertainties related to differences in the model's structure and its parametrizations on the one hand and the need for simplifying assumptions for the representation of irrigation on the other hand. To address these uncertainties, we used the Max Planck Institute for Meteorology's Earth System model into which a simple irrigation scheme was implemented. In order to estimate possible uncertainties with regard to the model's more general structure, we compared the climate impact of irrigation between three simulations that use different schemes for the land-surface-atmosphere coupling. Here, it can be shown that the choice of coupling scheme does not only affect the magnitude of possible impacts but even their direction. For example, when using a scheme that does not explicitly resolve spatial subgrid scale heterogeneity at the surface, irrigation reduces the atmospheric water content, even in heavily irrigated regions. Contrarily, in simulations that use a coupling scheme that resolves heterogeneity at the surface or even within the lowest layers of the atmosphere, irrigation increases the average atmospheric specific humidity. A second experiment targeted possible uncertainties related to the representation of irrigation characteristics. Here, in four simulations the irrigation effectiveness (controlled by the target soil moisture and the non-vegetated fraction of the grid box that receives irrigation) and the timing of delivery were varied. The second experiment shows that uncertainties related to the modelled irrigation characteristics, especially the irrigation effectiveness, are also substantial. In general the impact of irrigation on the state of the land surface is more than three times larger when assuming a low irrigation effectiveness than when a high effectiveness is assumed. For certain variables, such as the vertically integrated water vapour, the impact is almost an order of magnitude larger. The timing of irrigation also has non-negligible effects on the simulated climate impacts and it can strongly alter their seasonality.

Nasal Irrigation for Chronic Rhinosinusitis and Fatigue in Patients with Gulf War Syndrome

DTIC Science & Technology

2012-07-01

final R&D Committee approval was granted on 7/16/12 We were also recently informed that the company that will provide Xylitol (Danisco) has been...communication with Danisco-Dupont regarding continuity of study regarding procurement and packaging of xylitol packets (saches) for individual use by...participants in the xylitol arm of the study. These communications have been positive and the study remains a priority of Danisco-Dupont. The PI, study

Invisible water, visible impact: groundwater use and Indian agriculture under climate change

DOE PAGES

Zaveri, Esha; Grogan, Danielle S.; Fisher-Vanden, Karen; ...

2016-08-03

India is one of the world's largest food producers, making the sustainability of its agricultural system of global significance. Groundwater irrigation underpins India's agriculture, currently boosting crop production by enough to feed 170 million people. Groundwater overexploitation has led to drastic declines in groundwater levels, threatening to push this vital resource out of reach for millions of small-scale farmers who are the backbone of India's food security. Historically, losing access to groundwater has decreased agricultural production and increased poverty. We take a multidisciplinary approach to assess climate change challenges facing India's agricultural system, and to assess the effectiveness of large-scalemore » water infrastructure projects designed to meet these challenges. We find that even in areas that experience climate change induced precipitation increases, expansion of irrigated agriculture will require increasing amounts of unsustainable groundwater. Finally, the large proposed national river linking project has limited capacity to alleviate groundwater stress. Thus, without intervention, poverty and food insecurity in rural India is likely to worsen.« less

Invisible water, visible impact: groundwater use and Indian agriculture under climate change

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zaveri, Esha; Grogan, Danielle S.; Fisher-Vanden, Karen

India is one of the world's largest food producers, making the sustainability of its agricultural system of global significance. Groundwater irrigation underpins India's agriculture, currently boosting crop production by enough to feed 170 million people. Groundwater overexploitation has led to drastic declines in groundwater levels, threatening to push this vital resource out of reach for millions of small-scale farmers who are the backbone of India's food security. Historically, losing access to groundwater has decreased agricultural production and increased poverty. We take a multidisciplinary approach to assess climate change challenges facing India's agricultural system, and to assess the effectiveness of large-scalemore » water infrastructure projects designed to meet these challenges. We find that even in areas that experience climate change induced precipitation increases, expansion of irrigated agriculture will require increasing amounts of unsustainable groundwater. Finally, the large proposed national river linking project has limited capacity to alleviate groundwater stress. Thus, without intervention, poverty and food insecurity in rural India is likely to worsen.« less

Climate change, water rights, and water supply: The case of irrigated agriculture in Idaho

NASA Astrophysics Data System (ADS)

Xu, Wenchao; Lowe, Scott E.; Adams, Richard M.

2014-12-01

We conduct a hedonic analysis to estimate the response of agricultural land use to water supply information under the Prior Appropriation Doctrine by using Idaho as a case study. Our analysis includes long-term climate (weather) trends and water supply conditions as well as seasonal water supply forecasts. A farm-level panel data set, which accounts for the priority effects of water rights and controls for diversified crop mixes and rotation practices, is used. Our results indicate that farmers respond to the long-term surface and ground water conditions as well as to the seasonal water supply variations. Climate change-induced variations in climate and water supply conditions could lead to substantial damages to irrigated agriculture. We project substantial losses (up to 32%) of the average crop revenue for major agricultural areas under future climate scenarios in Idaho. Finally, farmers demonstrate significantly varied responses given their water rights priorities, which imply that the distributional impact of climate change is sensitive to institutions such as the Prior Appropriation Doctrine.

Statistical attribution analysis of the nonstationarity of the annual runoff series of the Weihe River.

PubMed

Xiong, Lihua; Jiang, Cong; Du, Tao

2014-01-01

Time-varying moments models based on Pearson Type III and normal distributions respectively are built under the generalized additive model in location, scale and shape (GAMLSS) framework to analyze the nonstationarity of the annual runoff series of the Weihe River, the largest tributary of the Yellow River. The detection of nonstationarities in hydrological time series (annual runoff, precipitation and temperature) from 1960 to 2009 is carried out using a GAMLSS model, and then the covariate analysis for the annual runoff series is implemented with GAMLSS. Finally, the attribution of each covariate to the nonstationarity of annual runoff is analyzed quantitatively. The results demonstrate that (1) obvious change-points exist in all three hydrological series, (2) precipitation, temperature and irrigated area are all significant covariates of the annual runoff series, and (3) temperature increase plays the main role in leading to the reduction of the annual runoff series in the study basin, followed by the decrease of precipitation and the increase of irrigated area.

Assessing the changes of groundwater recharge / irrigation water use between SRI and traditional irrigation schemes in Central Taiwan

NASA Astrophysics Data System (ADS)

Chen, Shih-Kai; Jang, Cheng-Shin; Tsai, Cheng-Bin

2015-04-01

To respond to agricultural water shortage impacted by climate change without affecting rice yield in the future, the application of water-saving irrigation, such as SRI methodology, is considered to be adopted in rice-cultivation in Taiwan. However, the flooded paddy fields could be considered as an important source of groundwater recharge in Central Taiwan. The water-saving benefit of this new methodology and its impact on the reducing of groundwater recharge should be integrally assessed in this area. The objective of this study was to evaluate the changes of groundwater recharge/ irrigation water use between the SRI and traditional irrigation schemes (continuous irrigation, rotational irrigation). An experimental paddy field located in the proximal area of the Choushui River alluvial fan (the largest groundwater pumping region in Taiwan) was chosen as the study area. The 3-D finite element groundwater model (FEMWATER) with the variable boundary condition analog functions, was applied in simulating groundwater recharge process and amount under traditional irrigation schemes and SRI methodology. The use of effective rainfall was taken into account or not in different simulation scenarios for each irrigation scheme. The simulation results showed that there were no significant variations of infiltration rate in the use of effective rainfall or not, but the low soil moisture setting in deep soil layers resulted in higher infiltration rate. Taking the use of effective rainfall into account, the average infiltration rate for continuous irrigation, rotational irrigation, and SRI methodology in the first crop season of 2013 were 4.04 mm/day, 4.00 mm/day and 3.92 mm/day, respectively. The groundwater recharge amount of SRI methodology was slightly lower than those of traditional irrigation schemes, reducing 4% and 2% compared with continuous irrigation and rotational irrigation, respectively. The field irrigation requirement amount of SRI methodology was significantly lower than those of traditional irrigation schemes, saving 35% and 9% compared with continuous irrigation and rotational irrigation, respectively. The SRI methodology significantly improved water-saving benefit compared with the disadvantage of reducing groundwater recharge. The results could be used as a basis for the relevant government agency to formulate the integral water resource management strategies in this area. Keywords: SRI, Paddy field, Infiltration, Groundwater recharge

Integrating Growth Stage Deficit Irrigation into a Process Based Crop Model

NASA Technical Reports Server (NTRS)

Lopez, Jose R.; Winter, Jonathan M.; Elliott, Joshua; Ruane, Alex C.; Porter, Cheryl; Hoogenboom, Gerrit

2017-01-01

Current rates of agricultural water use are unsustainable in many regions, creating an urgent need to identify improved irrigation strategies for water limited areas. Crop models can be used to quantify plant water requirements, predict the impact of water shortages on yield, and calculate water productivity (WP) to link water availability and crop yields for economic analyses. Many simulations of crop growth and development, especially in regional and global assessments, rely on automatic irrigation algorithms to estimate irrigation dates and amounts. However, these algorithms are not well suited for water limited regions because they have simplistic irrigation rules, such as a single soil-moisture based threshold, and assume unlimited water. To address this constraint, a new modeling framework to simulate agricultural production in water limited areas was developed. The framework consists of a new automatic irrigation algorithm for the simulation of growth stage based deficit irrigation under limited seasonal water availability; and optimization of growth stage specific parameters. The new automatic irrigation algorithm was used to simulate maize and soybean in Gainesville, Florida, and first used to evaluate the sensitivity of maize and soybean simulations to irrigation at different growth stages and then to test the hypothesis that water productivity calculated using simplistic irrigation rules underestimates WP. In the first experiment, the effect of irrigating at specific growth stages on yield and irrigation water use efficiency (IWUE) in maize and soybean was evaluated. In the reproductive stages, IWUE tended to be higher than in the vegetative stages (e.g. IWUE was 18% higher than the well watered treatment when irrigating only during R3 in soybean), and when rainfall events were less frequent. In the second experiment, water productivity (WP) was significantly greater with optimized irrigation schedules compared to non-optimized irrigation schedules in water restricted scenarios. For example, the mean WP across 38 years of maize production was 1.1 kg/cu m for non-optimized irrigation schedules with 50 mm of seasonal available water and 2.1 kg/cu m optimized ion schedules, a 91% improvement in WP with optimized irrigation schedules. The framework described in this work could be used to estimate WP for regional to global assessments, as well as derive location specific irrigation guidance.

Reuse potential of laundry greywater for irrigation based on growth, water and nutrient use of tomato

NASA Astrophysics Data System (ADS)

Misra, R. K.; Patel, J. H.; Baxi, V. R.

2010-05-01

SummaryGreywater is considered as a valuable resource with a high reuse potential for irrigation of household lawns and gardens. However, there are possibilities of surfactant and sodium accumulation in soil from reuse of greywater which may affect agricultural productivity and environmental sustainability adversely. We conducted a glasshouse experiment to examine variation in growth, water and nutrient use of tomato ( Lycopersicon esculentum Mill. cv. Grosse Lisse) using tap water (TW), laundry greywater (GW) and solutions of low and high concentration of a detergent surfactant (LC and HC, respectively) as irrigation treatments. Each treatment was replicated five times using a randomised block design. Measurements throughout the experiment showed greywater to be significantly more alkaline and saline than the other types of irrigation water. Although all plants received 16 irrigations over a period of 9 weeks until flowering, there were little or no significant effects of irrigation treatments on plant growth. Soil water retention following irrigation reduced significantly when plants were irrigated with GW or surfactant solutions on only three of 12 occasions. On one occasion, water use measured as evapotranspiration (ET) with GW irrigation was similar to TW, but it was significantly higher than the plants receiving HC irrigation. At harvest, various components of plant biomass and leaf area for GW irrigated plants were found to be similar or significantly higher than the TW irrigated plants with a common trend of GW ⩾ TW > LC ⩾ HC. Whole-plant concentration was measured for 12 essential plant nutrients (N, P, K, Ca, Mg, S, Fe, Cu, Mn, Zn, Mo and B) and Na (often considered as a beneficial nutrient). Irrigation treatments affected the concentration of four nutrients (P, Fe, Zn and Na) and uptake of seven nutrients (P, K, Ca, Mg, Na, Fe and B) significantly. Uptake of these seven nutrients by tomato was generally in the order GW ⩾ TW > HC ⩾ LC. GW irrigated plants had the highest concentration of P, Na and Fe which were 39-85% higher than the TW irrigated plants. Compared with tap water irrigated plants, greywater irrigated plants removed only 6% excess B, but substantially greater quantity of Na (83%) and Fe (86%). These results suggest that laundry greywater has a promising potential for reuse as irrigation water to grow tomato.

Identifying the interferences of irrigation on evapotranspiration variability over the Northern High Plains

NASA Astrophysics Data System (ADS)

Zeng, R.; Cai, X.

2016-12-01

Irrigation has considerably interfered with hydrological processes in arid and semi-arid areas with heavy irrigated agriculture. With the increasing demand for food production and evaporative demand due to climate change, irrigation water consumption is expected to increase, which would aggravate the interferences to hydrologic processes. Current studies focus on the impact of irrigation on the mean value of evapotranspiration (ET) at either local or regional scale, however, how irrigation changes the variability of ET has not been well understood. This study analyzes the impact of extensive irrigation on ET variability in the Northern High Plains. We apply an ET variance decomposition framework developed from our previous work to quantify the effects of both climate and irrigation on ET variance in the Northern High Plains watersheds. Based on climate and water table observations, we assess the monthly ET variance and its components for two periods: 1930s-1960s with less irrigation development 970s-2010s with more development. It is found that irrigation not only caused the well-recognized groundwater drawdown and stream depletion problems in the region, but also buffered ET variance from climatic fluctuations. In addition to increasing food productivity, irrigation also stabilizes crop yield by mitigating the impact of hydroclimatic variability. With complementary water supply from irrigation, ET often approaches to the potential ET, and thus the observed ET variance is more attributed to climatic variables especially temperature; meanwhile irrigation causes significant seasonal fluctuations to groundwater storage. For sustainable water resources management in the Northern High Plains, we argue that both the mean value and the variance of ET should be considered together for the regulation of irrigation in this region.

Assessment of Irrigation Physics in a Land Surface Modeling Framework Using Non-Traditional and Human-Practice Datasets

NASA Technical Reports Server (NTRS)

Lawston, Patricia M.; Santanello, Joseph A.; Rodell, Matthew; Franz, Trenton E.

2017-01-01

Irrigation increases soil moisture, which in turn controls water and energy fluxes from the land surface to the10 planetary boundary layer and determines plant stress and productivity. Therefore, developing a realistic representation of irrigation is critical to understanding land-atmosphere interactions in agricultural areas. Irrigation parameterizations are becoming more common in land surface models and are growing in sophistication, but there is difficulty in assessing the realism of these schemes, due to limited observations (e.g., soil moisture, evapotranspiration) and scant reporting of irrigation timing and quantity. This study uses the Noah land surface model run at high resolution within NASAs Land15 Information System to assess the physics of a sprinkler irrigation simulation scheme and model sensitivity to choice of irrigation intensity and greenness fraction datasets over a small, high resolution domain in Nebraska. Differences between experiments are small at the interannual scale but become more apparent at seasonal and daily time scales. In addition, this study uses point and gridded soil moisture observations from fixed and roving Cosmic Ray Neutron Probes and co-located human practice data to evaluate the realism of irrigation amounts and soil moisture impacts simulated by the model. Results20 show that field-scale heterogeneity resulting from the individual actions of farmers is not captured by the model and the amount of irrigation applied by the model exceeds that applied at the two irrigated fields. However, the seasonal timing of irrigation and soil moisture contrasts between irrigated and non-irrigated areas are simulated well by the model. Overall, the results underscore the necessity of both high-quality meteorological forcing data and proper representation of irrigation foraccurate simulation of water and energy states and fluxes over cropland.

Partial root-zone drying and conventional deficit irrigation applied during the whole berry growth maintain yield and berry quality in 'Crimson Seedless' table grapes

NASA Astrophysics Data System (ADS)

Pérez-Pastor, Alejandro; Domingo, Rafael; De la Rosa, Jose M.°; Rosario Conesa Saura, M.°

2016-04-01

To compare the effects of partial root-zone drying and conventional deficit irrigation applied during post-veraison and the whole berry growth on water relations, yield and berry quality, one experiment was conducted in a commercial vineyard of 'Crimson Seedless' table grapes. Five irrigation treatments were imposed: (i) Control (CTL) irrigated to 110% of crop evapotranspiration (ETc), (ii) regulated deficit irrigation (RDI) irrigated at 50% of CTL during the non- critical period of post-verasion, (iii) continuous deficit irrigation (DIc), irrigated at 50% of CTL throughout the whole berry growing season, (iv) partial root-zone drying (PRD), irrigated similar to RDI, but alternating the irrigation applied in the dry side every 10-14 days; and (v) continuous partial root-zone drying (PRDc), irrigated as DIc but alternating the irrigation in the dry side every 10-14 days. RDI and PRD received 24% and 28% less water than CTL, respectively. These reductions were higher in DIc and PRDc (65% and 53%, respectively). Total yield was not affected by any DI strategy. Only significantly lower values were observed in the weight and height's berries in respect to CTL. However, the colour parameters evaluated increased in all DI treatments, being slightly higher in DIc and PRDc compared with RDI and PRD. In addition, total soluble solids (TSS) were significantly higher in DIc, compared to other irrigated counterparts. Our findings showed that the application of water deficit during the whole berry growth through the use of DIc and PRDc, can be considered for irrigation scheduling in 'Crimson Seedless' table grapes. Acknowledgements This work has been funded by the European Union LIFE+ project IRRIMAN (LIFE13 ENV/ES/000539).

The sensitivity of southeastern United States climate to varying irrigation vigor

NASA Astrophysics Data System (ADS)

Selman, Christopher; Misra, Vasubandhu

2016-07-01

Four regional climate model runs centered on the Southeast United States (SEUS) assuming a crop growing season of May through October are irrigated at 25% (IRR25), 50% (IRR50), 75% (IRR75), and 100% (IRR100) of the root zone porosity to assess the sensitivity of the SEUS climate to irrigation. A fifth run, assuming no irrigation (CTL), is used as the basis for comparison. Across all IRR runs, it is found that there is a general reduction in seasonal mean precipitation over the irrigated cells relative to CTL. This manifests as an increase in dry (0-1 mm/d) days and reduction in > 1 mm/d rainfall events. A comparative moisture budget reveals that area-averaged precipitation over the irrigated cells displays a reduction in precipitation and runoff in IRR100 with a weaker reduction in IRR25. This is despite an increase in vertically integrated moisture convergence and local evaporation. We find that irrigation increases the lower atmospheric stability, which in turn reduces the convective rainfall over the irrigated areas. Seasonally averaged temperatures reduce over irrigated areas, with the intensity of the reduction increasing with irrigation vigor. This is largely attributed to a repartitioning of sensible heat flux into latent heat flux. There is also, however, a small increase of heat flow to deeper soil layers. Precipitation ahead of transient cold fronts is also reduced by irrigation as they pass over irrigated cells, owing to the increased stability in the lower troposphere. The intensity of this precipitation reduction becomes more intense as irrigation vigor increases. Lastly, heat waves in the SEUS are reduced in intensity over irrigated cells.

Influence of resolution in irrigated area mapping and area estimation

USGS Publications Warehouse

Velpuri, N.M.; Thenkabail, P.S.; Gumma, M.K.; Biradar, C.; Dheeravath, V.; Noojipady, P.; Yuanjie, L.

2009-01-01

The overarching goal of this paper was to determine how irrigated areas change with resolution (or scale) of imagery. Specific objectives investigated were to (a) map irrigated areas using four distinct spatial resolutions (or scales), (b) determine how irrigated areas change with resolutions, and (c) establish the causes of differences in resolution-based irrigated areas. The study was conducted in the very large Krishna River basin (India), which has a high degree of formal contiguous, and informal fragmented irrigated areas. The irrigated areas were mapped using satellite sensor data at four distinct resolutions: (a) NOAA AVHRR Pathfinder 10,000 m, (b) Terra MODIS 500 m, (c) Terra MODIS 250 m, and (d) Landsat ETM+ 30 m. The proportion of irrigated areas relative to Landsat 30 m derived irrigated areas (9.36 million hectares for the Krishna basin) were (a) 95 percent using MODIS 250 m, (b) 93 percent using MODIS 500 m, and (c) 86 percent using AVHRR 10,000 m. In this study, it was found that the precise location of the irrigated areas were better established using finer spatial resolution data. A strong relationship (R2 = 0.74 to 0.95) was observed between irrigated areas determined using various resolutions. This study proved the hypotheses that "the finer the spatial resolution of the sensor used, greater was the irrigated area derived," since at finer spatial resolutions, fragmented areas are detected better. Accuracies and errors were established consistently for three classes (surface water irrigated, ground water/conjunctive use irrigated, and nonirrigated) across the four resolutions mentioned above. The results showed that the Landsat data provided significantly higher overall accuracies (84 percent) when compared to MODIS 500 m (77 percent), MODIS 250 m (79 percent), and AVHRR 10,000 m (63 percent). ?? 2009 American Society for Photogrammetry and Remote Sensing.

[Effects of irrigation and planting patterns on photosynthetic characteristics of flag leaf and yield at late growth stages of winter wheat].

PubMed

Dong, Hao; Bi, Jun; Xia, Guang-Li; Zhou, Xun-Bo; Chen, Yu-Hai

2014-08-01

High-yield winter wheat cultivar Jimai 22 was used to study effects of irrigation and planting patterns on water consumption characteristics and photosynthetic characteristics of winter wheat in field from 2009 to 2011. Three different planting patterns (uniform row, wide-narrow row and furrow) and four irrigation schedules (W0, no irrigation; W1, irrigation at jointing stage; W2, irrigations at jointing and anthesis stages; W3, irrigation at jointing, anthesis and milking stages. Each irrigation rate was 60 mm) were designed in the experiment. Results showed that, with the increasing of irrigation amount, flag leaf area, net photosynthesis rate, maximum photochemical efficiency and actual light transformation efficiency at late growth stages of winter wheat increased. Compared with W0 treatment, the other irrigation treatments had higher grain yields, but lower water use efficiencies. Under the same irrigation condition, the flag leaf net photosynthesis, maximum photochemical efficiency and actual light transformation efficiency were much higher in furrow pattern. Grain yields of winter wheat under furrow pattern and W2 treatment were significantly higher than that of the other treatments. Taking grain yield and WUE into consideration, furrow pattern combined with irrigation at jointing and anthesis stages might be the optimal water-saving and planting mode for the winter wheat production in North China Plain.

Does apical negative pressure prevent the apical extrusion of debris and irrigant compared with conventional irrigation? A systematic review and meta-analysis.

PubMed

Romualdo, Priscilla Coutinho; de Oliveira, Katharina Morant Holanda; Nemezio, Mariana Alencar; Küchler, Erika Calvano; Silva, Raquel Assed Bezerra; Nelson-Filho, Paulo; Silva, Lea Assed Bezerra

2017-12-01

The aim of this study was to evaluate if apical negative pressure (ANP) irrigation prevents the apical extrusion of debris and irrigant compared with conventional needle irrigation through a systematic review and meta-analysis. A computer search of dental literature was performed using four different databases. A combination of the terms 'apical negative pressure', 'endovac', 'apical extrusion', 'extrusion' and 'endodontics' was used. Studies that used extracted human teeth with a mature apex and that evaluated the apical extrusion of debris and/or irrigating solution were included. After an evaluation of the full studies according to the eligibility criteria, eight studies were critically analysed and subjected to quality assessment and risk of bias. Only four studies that evaluated extrusion of irrigant were considered as having high methodological quality and were subjected to a meta-analysis. Studies evaluating extrusion of debris did not have sufficient methodological quality to be subjected to the meta-analysis. The forest plot indicated that ANP irrigation prevents the risk of irrigant extrusion compared with conventional irrigation (OR 0.07 [95%CI 0.02-0.20]; P < 0.00001). This systematic review and meta-analysis showed that ANP prevents the apical extrusion of irrigant. There is no evidence if this type of irrigation prevents the extrusion of debris. © 2017 Australian Society of Endodontology Inc.

Mapping irrigated lands at 250-m scale by merging MODIS data and National Agricultural Statistics

USGS Publications Warehouse

Pervez, Md Shahriar; Brown, Jesslyn F.

2010-01-01

Accurate geospatial information on the extent of irrigated land improves our understanding of agricultural water use, local land surface processes, conservation or depletion of water resources, and components of the hydrologic budget. We have developed a method in a geospatial modeling framework that assimilates irrigation statistics with remotely sensed parameters describing vegetation growth conditions in areas with agricultural land cover to spatially identify irrigated lands at 250-m cell size across the conterminous United States for 2002. The geospatial model result, known as the Moderate Resolution Imaging Spectroradiometer (MODIS) Irrigated Agriculture Dataset (MIrAD-US), identified irrigated lands with reasonable accuracy in California and semiarid Great Plains states with overall accuracies of 92% and 75% and kappa statistics of 0.75 and 0.51, respectively. A quantitative accuracy assessment of MIrAD-US for the eastern region has not yet been conducted, and qualitative assessment shows that model improvements are needed for the humid eastern regions where the distinction in annual peak NDVI between irrigated and non-irrigated crops is minimal and county sizes are relatively small. This modeling approach enables consistent mapping of irrigated lands based upon USDA irrigation statistics and should lead to better understanding of spatial trends in irrigated lands across the conterminous United States. An improved version of the model with revised datasets is planned and will employ 2007 USDA irrigation statistics.

Estimation of furrow irrigation sediment loss using an artificial neural network

USDA-ARS?s Scientific Manuscript database

The area irrigated by furrow irrigation in the U.S. has been steadily decreasing but still represents about 20% of the total irrigated area in the U.S. Furrow irrigation sediment loss is a major water quality issue and a method for estimating sediment loss is needed to quantify the environmental imp...

Irrigation management using an expert system, soil water potentials, and vegetative indices for spatial applications

USDA-ARS?s Scientific Manuscript database

Variable rate irrigation (VRI) systems are irrigation systems that are capable of applying different water depths both in the direction of travel and along the length of the irrigation system. However, when compared to traditional irrigation systems, VRI systems require a higher level of management...

Influence of deficit irrigation strategies on fatty acid and tocopherol concentration of almond (Prunus dulcis).

PubMed

Zhu, Ying; Taylor, Cathy; Sommer, Karl; Wilkinson, Kerry; Wirthensohn, Michelle

2015-04-15

The effects of deficit irrigation on almond fatty acid and tocopherol levels were studied in a field trial. Mature almond trees were subjected to three levels of deficit irrigation (85%, 70% and 55% of potential crop evapotranspiration (ETo), as well as control (100% ETo) and over-irrigation (120% ETo) treatments. Two deficit irrigation strategies were employed: regulated deficit irrigation (RDI) and sustained deficit irrigation (SDI). Moderate deficit irrigation (85% RDI and 85% SDI) had no detrimental impact on almond kernel lipid content, but severe and extreme deficiencies (70% and 55%) influenced lipid content. Unsaturated fatty acid (USFA) and saturated fatty acid (SFA) contents fluctuated under these treatments, the oleic/linoleic ratio increased under moderate water deficiency, but decreased under severe and extreme water deficiency. Almond tocopherols concentration was relatively stable under deficit irrigation. The variation between years indicated climate has an effect on almond fruit development. In conclusion it is feasible to irrigate almond trees using less water than the normal requirement, without significant loss of kernel quality. Copyright © 2014 Elsevier Ltd. All rights reserved.

Evaluation of the effects of mulch on optimum sowing date and irrigation management of zero till wheat in central Punjab, India using APSIM.

PubMed

Balwinder-Singh; Humphreys, E; Gaydon, D S; Eberbach, P L

2016-10-01

Machinery for sowing wheat directly into rice residues has become more common in the rice-wheat systems of the north-west Indo-Gangetic Plains of South Asia, with increasing numbers of farmers now potentially able to access the benefits of residue retention. However, surface residue retention affects soil water and temperature dynamics, thus the optimum sowing date and irrigation management for a mulched crop may vary from those of a traditional non-mulched crop. Furthermore, the effects of sowing date and irrigation management are likely to vary with soil type and seasonal conditions. Therefore, a simulation study was conducted using the APSIM model and 40 years of weather data to evaluate the effects of mulch, sowing date and irrigation management and their interactions on wheat grain yield, irrigation requirement (I) and water productivity with respect to irrigation (WP I ) and evapotranspiration (WP ET ). The results suggest that the optimum wheat sowing date in central Punjab depends on both soil type and the presence or absence of mulch. On the sandy loam, with irrigation scheduled at 50% soil water deficit (SWD), the optimum sowing date was late October to early November for maximising yield, WP I and WP ET . On the clay loam, the optimum date was about one week later. The effect of mulch on yield varied with seasonal conditions and sowing date. With irrigation at 50% SWD, mulching of wheat sown at the optimum time increased average yield by up to 0.5 t ha -1 . The beneficial effect of mulch on yield increased to averages of 1.2-1.3 t ha -1 as sowing was advanced to 15 October. With irrigation at 50% SWD and 7 November sowing, mulch reduced the number of irrigations by one in almost 50% of years, a reduction of about 50 mm on the sandy loam and 60 mm on the clay loam. The reduction in irrigation amount was mainly due to reduced soil evaporation. Mulch reduced irrigation requirement by more as sowing was delayed, more so on the sandy loam than the clay loam soil. There was little effect of mulch on irrigation requirement for late October sowings. There were large trade-offs between irrigation input, yield, WP ET and WP I on the sandy loam with regard to the optimum irrigation schedule. Maximum yield occurred with very frequent irrigation (10-20% SWD) which also had the greatest irrigation input, while WP I was highest with least frequent irrigation (70% SWD), and WP ET was highest with irrigation at 40-50% SWD. This was the case with and without mulch. On the clay loam, the trade-offs were not so pronounced, as maximum yield was reached with irrigation at 50% SWD, with and without mulch. However, both WP ET and WP I were maximum and irrigation input least at the lowest irrigation frequency (70% SWD). On both soils, maximum yield, WP ET and WP I were higher with mulch, while irrigation input was slightly lower, but mulch had very little effect on the irrigation thresholds at which each parameter was maximised.

Water budget and simulation of one-dimensional unsaturated flow for a flood- and a sprinkler-irrigated field near Milford, Utah

USGS Publications Warehouse

Susong, David D.

1995-01-01

Ground-water recharge to basin-fill aquifers from unconsumed irrigation water in the western United States is being reduced as irrigators convert to more efficient irrigation systems. In some areas, these changes in irrigation methods may be contributing to ground-water-level declines and reducing the quantity of water available to downgradient users. The components of the water budget were measured or calculated for each field for the 1992 and 1993 irrigation seasons. Precipitation was about 6.5 cm (2.6 inches) both years. The flood-irrigated field received 182 and 156 centimeters (71.6 and 61.4 inches) of irrigation water in 1992 and 1993, and the sprinkler-irrigated field received 52.8 and 87.2 centimeters (20.8 and 34.3 inches) of water, respectively. Evapotranspiration for alfalfa was calculated using the Penman-Monteith combination equation and was 95.4 and 84.3 centimeters (37.2 and 33.2 inches) for 1992 and 1993, respectively. No runoff and no significant change in soil moisture in storage was observed from either field. Recharge to the aquifer from the flood-irrigated field was 93.3 and 78.1 centimeters (36.7 and 30.7 inches) in 1992 and 1993 and from the sprinkler-irrigated field was -35.9 and 9.3 centimeters (-14.1 and 3.7 inches), respectively. The daily water budget and soil-moisture profiles in the upper 6.4 meters (21 feet) of the unsaturated zone were simulated with an unsaturated flow model for average climate conditions. Simulated recharge was 57.4 and 50.5 percent of the quantity of irrigation water applied to the flood-irrigated field during 1992 and 1993, respectively, and was 8.7 and 13.8 percent of the quantity of irrigation water applied to the sprinkler- irrigated field.

Water budget and simulation of one-dimensional unsaturated flow for a flood- and a sprinkler-irrigated field near Milford, Utah

USGS Publications Warehouse

Susong, D.D.

1995-01-01

Ground-water recharge to basin-fill aquifers from unconsumed irrigation water in the western United States is being reduced as irrigators convert to more efficient irrigation systems. In some areas, these changes in irrigation methods may be contributing to ground-water-level declines and reducing the quantity of water available to downgradient users. The components of the water budget were measured or calculated for each field for the 1992 and 1993 irrigation seasons. Precipitation was about 6.5 cm (2.6 inches) both years. The flood-irrigated field received 182 and 156 centimeters (71.6 and 61.4 inches) of irrigation water in 1992 and 1993, and the sprinkler-irrigated field received 52.8 and 87.2 centimeters (20.8 and 34.3 inches) of water, respectively. Evapotrans- piration for alfalfa was calculated using the Penman-Monteith combination equation and was 95.4 and 84.3 centimeters (37.2 and 33.2 inches) for 1992 and 1993, respectively. No runoff and no signifi- cant change in soil moisture in storage was observed from either field. Recharge to the aquifer from the flood-irrigated field was 93.3 and 78.1 centimeters (36.7 and 30.7 inches) in 1992 and 1993 and from the sprinkler-irrigated field was -35.9 and 9.3 centimeters (-14.1 and 3.7 inches), respectively. The daily water budget and soil-moisture profiles in the upper 6.4 meters (21 feet) of the unsaturated zone were simulated with an unsaturated flow model for average climate conditions. Simulated recharge was 57.4 and 50.5 percent of the quantity of irrigation water applied to the flood-irrigated field during 1992 and 1993, respectively, and was 8.7 and 13.8 percent of the quantity of irrigation water applied to the sprinkler-irrigated field.

[Influences of micro-irrigation and subsoiling before planting on enzyme activity in soil rhizosphere and summer maize yield.

PubMed

Zhang, Ming Zhi; Niu, Wen Quan; Xu, Jian; Li, Yuan

2016-06-01

In order to explore the influences of micro-irrigation and subsoiling before planting on enzyme activity in soil rhizosphere and summer maize yield, an orthogonal experiment was carried out with three factors of micro-irrigation method, irrigation depth, and subsoiling depth. The factor of irrigation method included surface drip irrigation, subsurface drip irrigation, and moistube-irrigation; three levels of irrigation depth were obtained by controlling the lower limit of soil water content to 50%, 65%, and 80% of field holding capacity, respectively; and three depths of deep subsoiling were 20, 40, and 60 cm. The results showed that the activities of catalase and urease increased first and then decreased, while the activity of phosphatase followed an opposite trend in the growth season of summer maize. Compared with surface drip irrigation and moistube-irrigation, subsurface drip irrigation increased the average soil moisture of 0-80 cm layer by 6.3% and 1.8% in the growth season, respectively. Subsurface drip irrigation could significantly increase soil urease activity, roots volume, and yield of summer maize. With the increase of irrigation level, soil phosphatase activity decreased first and then increased, while urease activity and yield increased first and then decreased. The average soil moisture and root volume all increased in the growth season of summer maize. The increments of yield and root volume from subsoiling of 40 to 20 cm were greater than those from 60 to 40 cm. The highest enzyme activity was obtained with the treatment of subsoiling of 40 cm. In terms of improving water resource use efficiency, nitrogen use efficiency, and crop yield, the best management strategy of summer maize was the combination of subsurface drip irrigation, controlling the lower limit of soil water content to 65% of field holding capacity, and 40 cm subsoiling before planting.

Study on the quantitative relationship between Agricultural water and fertilization process and non-point source pollution based on field experiments

NASA Astrophysics Data System (ADS)

Wang, H.; Chen, K.; Wu, Z.; Guan, X.

2017-12-01

In recent years, with the prominent of water environment problem and the relative increase of point source pollution governance, especially the agricultural non-point source pollution problem caused by the extensive use of fertilizers and pesticides has become increasingly aroused people's concern and attention. In order to reveal the quantitative relationship between agriculture water and fertilizer and non-point source pollution, on the basis of elm field experiment and combined with agricultural drainage irrigation model, the agricultural irrigation water and the relationship between fertilizer and fertilization scheme and non-point source pollution were analyzed and calculated by field emission intensity index. The results show that the variation of displacement varies greatly under different irrigation conditions. When the irrigation water increased from 22cm to 42cm, the irrigation water increased by 20 cm while the field displacement increased by 11.92 cm, about 66.22% of the added value of irrigation water. Then the irrigation water increased from 42 to 68, irrigation water increased 26 cm, and the field displacement increased by 22.48 cm, accounting for 86.46% of irrigation water. So there is an "inflection point" between the irrigation water amount and field displacement amount. The load intensity increases with the increase of irrigation water and shows a significant power correlation. Under the different irrigation condition, the increase amplitude of load intensity with the increase of irrigation water is different. When the irrigation water is smaller, the load intensity increase relatively less, and when the irrigation water increased to about 42 cm, the load intensity will increase considerably. In addition, there was a positive correlation between the fertilization and load intensity. The load intensity had obvious difference in different fertilization modes even with same fertilization level, in which the fertilizer field unit load intensity increased the most in July. The results provide some basis for the field control and management of agricultural non-point source pollution.

On Equivalence between Critical Probabilities of Dynamic Gossip Protocol and Static Site Percolation

NASA Astrophysics Data System (ADS)

Ishikawa, Tetsuya; Hayakawa, Tomohisa

The relationship between the critical probability of gossip protocol on the square lattice and the critical probability of site percolation on the square lattice is discussed. Specifically, these two critical probabilities are analytically shown to be equal to each other. Furthermore, we present a way of evaluating the critical probability of site percolation by approximating the saturation of gossip protocol. Finally, we provide numerical results which support the theoretical analysis.

Irrigated Acreage Within the Basin and Range Carbonate-Rock Aquifer System, White Pine County, Nevada, and Adjacent Areas in Nevada and Utah

USGS Publications Warehouse

Welborn, Toby L.; Moreo, Michael T.

2007-01-01

Accurate delineations of irrigated acreage are needed for the development of water-use estimates and in determining water-budget calculations for the Basin and Range carbonate-rock aquifer system (BARCAS) study. Irrigated acreage is estimated routinely for only a few basins in the study area. Satellite imagery from the Landsat Thematic Mapper and Enhanced Thematic Mapper platforms were used to delineate irrigated acreage on a field-by-field basis for the entire study area. Six hundred and forty-three fields were delineated. The water source, irrigation system, crop type, and field activity for 2005 were identified and verified through field reconnaissance. These data were integrated in a geodatabase and analyzed to develop estimates of irrigated acreage for the 2000, 2002, and 2005 growing seasons by hydrographic area and subbasin. Estimated average annual potential evapotranspiration and average annual precipitation also were estimated for each field.The geodatabase was analyzed to determine the spatial distribution of field locations, the total amount of irrigated acreage by potential irrigation water source, by irrigation system, and by crop type. Irrigated acreage in 2005 totaled nearly 32,000 acres ranging from less than 200 acres in Butte, Cave, Jakes, Long, and Tippett Valleys to 9,300 acres in Snake Valley. Irrigated acreage increased about 20 percent between 2000 and 2005 and increased the most in Snake and White River Valleys. Ground-water supplies as much as 80 percent of irrigation water during dry years. Almost 90 percent of the irrigated acreage was planted with alfalfa.

Local Irrigation Management Institutions Mediate Changes Driven by External Policy and Market Pressures in Nepal and Thailand

NASA Astrophysics Data System (ADS)

Bastakoti, Ram C.; Shivakoti, Ganesh P.; Lebel, Louis

2010-09-01

This article assesses the role of local institutions in managing irrigation water use. Fifty irrigation systems in each country were studied in Nepal and Thailand to compare the influence of local institutions on performance of irrigation systems amid changes in external policy and market pressures. Nepal’s new irrigation policy after the re-instatement of multiparty democracy in 1990 emphasized participatory irrigation management transferring the management responsibility from state authorities to water users. The water user associations of traditional farmer-managed irrigation systems were formally recognized by requiring registration with related state authorities. In Thailand also government policies encouraged people’s participation in irrigation management. Today water users are directly involved in management of even some large irrigation systems at the level of tertiary canals. Traditional communal irrigation systems in northern Thailand received support for system infrastructure improvement but have faced increased interference from government. In Thailand market development supported diversification in farming practices resulting in increased areas under high water-demanding commercial crops in the dry season. In contrast, the command areas of most irrigation systems in Nepal include cereal-based subsistence farming with only one-third having commercial farming. Cropping intensities are higher in Nepal than in Thailand reflecting, in part, differences in availability of land and management. In both countries local institutions play an important role in maintaining the performance of irrigation systems as external drivers and local contexts change. Local institutions have provided alternative options for irrigation water use by mediating external pressures.