Mega-geomorphology and neotectonics

NASA Technical Reports Server (NTRS)

Lattman, L. H.

1985-01-01

For several decades, subtle neotectonic effects involving several square kilometers have been studied in detail using remote sensing, primarily various types of stereo-aerial photographs at scales of 1:10,000 to 1:80,000. These subtle effects, especially local uplifts associated with growing structures of differential compaction, have been detected by the effect on drainage patterns, changes in hydraulic geometry of individuals channels or groups of channels, tonal halos (soil) and fracture patterns. The studies were extended with the advent of thermal IR imagery particularly in tonal analysis, and SLAR primarily in fracture pattern studies. Lately, quantitative efforts have begun attempting to link measured uplift over known structures with measured changes in hydraulic geometry and alluvial deposition. Thus, efforts are now underway attempting to quantify the relationship between neo- (micro-) tectonic changes and geomorphic parameters of drainage systems.

Diuretic 99mTc DTPA renography in assessment of renal function and drainage in infants with antenatally detected hydronephrosis.

PubMed

Radulović, Marija; Pucar, Dragan; Jauković, Ljiljana; Sisić, Marija; Krstić, Zoran; Ajdinović, Boris

2015-12-01

The controversy over the postnatal management of infants with antenataly detected hydronephrosis (ANH) still exists. We presented the results of diuretic 99mTc diethylenetriamine pentaacetic acid (DTPA) renography in 30 infants with the antenatal diagnosis of unilateral renal pelvic dilatation. The aim of this study was to assess the renal function determined by the pattern of drainage and split renal function (SRF) on diuretic renography and to correlate these findings with anteroposterior pelvic diameter (APD) estimated by ultrasonography. A total of 30 infants with 60 renal units (RU) (25 boys and 5 girls, median age 6.0 months, range 2-24) presented with unilateral hydronephrosis on ultrasound in the newborn period, underwent DTPA diuretic renal scintigraphy (F+15 protocol). The median APD evaluated on perinatal ultrasound was 15 mm (range 5-30). The postnatal associated clinical diagnosis were pelviureteric junction obstruction (PUJ), simple hydronephrosis, megaureter, vesicoureteral reflux (VUR) and posterior urethral valves in 11, 10, 6, 2 and 1 infant, respectively. Images and Tmax/2 after diuretic stimulation on the background subtracted renographic curves were used as the criteria for classifying the drainage as good, partial, and poor or no drainage. The SRF was calculated with the integral method. Good drainage was shown in 36/60, partial drainage in 13/60 and poor or no drainage in 11/60 RU. The SRF > 40% was observed in 55/60 RU, with no RU showing SRF lower than 23.5%. In infants with severe ANH the obstruction was not excluded in 94.1%. Diuretic renography in antenatally detected hydronephrosis should be a useful tool in postnatal follow up, especially in differentiating nonobstructive hydronephrosis from obstructive. It is also importanat to assess and monitor the SRF. Our results suggest that even in the presence of partial or no drainage, SRF may not be significantly impaired.

Sternotomy or drainage for a hemopericardium after penetrating trauma: a randomized controlled trial.

PubMed

Nicol, Andrew J; Navsaria, Pradeep H; Hommes, Martijn; Ball, Chad G; Edu, Sorin; Kahn, Delawir

2014-03-01

To determine if stable patients with a hemopericardium detected after penetrating chest trauma can be safely managed with pericardial drainage alone. The current international practice is to perform a sternotomy and cardiac repair if a hemopericardium is detected after penetrating chest trauma. The experience in Cape Town, South Africa, on performing a mandatory sternotomy in hemodynamically stable patients was that a sternotomy was unnecessary and the cardiac injury, if present, had sealed. A single-center parallel-group randomized controlled study was completed. All hemodynamically stable patients with a hemopericardium confirmed at subxiphoid pericardial window (SPW), and no active bleeding, were randomized. The primary outcome measure was survival to discharge from hospital. Secondary outcomes were complications and postoperative hospital stay. Fifty-five patients were randomized to sternotomy and 56 to pericardial drainage and wash-out only. Fifty-one of the 55 patients (93%) randomized to sternotomy had either no cardiac injury or a tangential injury. There were only 4 patients with penetrating wounds to the endocardium and all had sealed. There was 1 death postoperatively among the 111 patients (0.9%) and this was in the sternotomy group. The mean intensive care unit (ICU) stay for a sternotomy was 2.04 days (range, 0-25 days) compared with 0.25 days (range, 0-2) for the drainage (P < 0.001). The estimated mean difference highlighted a stay of 1.8 days shorter in the ICU for the drainage group (95% CI: 0.8-2.7). Total hospital stay was significantly shorter in the SPW group (P < 0.001; 95% CI: 1.4-3.3). SPW and drainage is effective and safe in the stable patient with a hemopericardium after penetrating chest trauma, with no increase in mortality and a shorter ICU and hospital stay. (ClinicalTrials.gov Identifier: NCT00823160).

The usefulness of adding p53 immunocytochemistry to bile drainage cytology for the diagnosis of malignant biliary strictures.

PubMed

Yeo, Min-Kyung; Kim, Kyung-Hee; Lee, Yong-Moon; Lee, Byung Seok; Choi, Song-Yi

2017-07-01

Obstructive jaundice is frequently caused by bile duct strictures. Determination of malignant strictures is crucial for the initiation of appropriate treatment. Cytologic examination of bile drainage fluid is an easy and reproducible method of detecting malignant cells. This method, however, frequently yields indeterminate results, such as atypia or suspicious of malignancy, due to difficulties in differentiating malignancy from benign atypia. Immunocytochemical assessment of p53 expression by cells in bile drainage fluid may enhance the ability to detect malignancy. A total of 139 samples of bile drainage fluid were obtained from 80 patients. Following cytologic examination, the samples were incubated with antibody to p53. The performance of cytology with and without p53 immunocytochemistry was evaluated, with reference to surgical or clinical findings of benign and malignant biliary strictures. Bile drainage cytology alone had a sensitivity of 31.6% and a specificity of 98.4% in the identification of malignant strictures, whereas the combination of p53 immunocytochemistry and bile drainage cytology had a sensitivity of 80.3% and a specificity of 92.1%. P53 immunocytochemistry alone had a sensitivity of 64.5% and a specificity of 92.7% for the identification of malignant strictures in bile drainage samples with atypical cytology, and a sensitivity of 85.0% and a specificity of 100.0% in samples with suspicious of malignancy. The addition of p53 immunocytochemistry to bile drainage cytology can be useful in identifying malignant strictures in samples showing indeterminate results on bile drainage cytology. Diagn. Cytopathol. 2017;45:592-597. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Are there still roles for exocrine bladder drainage and portal venous drainage for pancreatic allografts?

PubMed

Young, Carlton J

2009-02-01

Controversy remains regarding the best methodology of handling exocrine pancreatic fluid and pancreatic venous effluent. Bladder drainage has given way to enteric drainage. However, is there an instance in which bladder drainage is preferable? Also, hyperinsulinemia, as a result of systemic venous drainage (SVD), is claimed to be proatherosclerotic, whereas portal venous drainage (PVD) is more physiologic and less atherosclerotic. Bladder drainage remains a viable method of exocrine pancreas drainage, but evidence is sparse that measuring urinary amylase has a substantial benefit in the early detection of acute rejection in all types of pancreas transplants. Currently, there is no incontrovertible evidence that systemic hyperinsulinemia is proatherosclerotic, whereas recent metabolic studies on SVD and PVD showed that there was no benefit to PVD. Given the advent of newer immunosuppressive agents and overall lower acute rejection rates, the perceived benefit of bladder drainage as a means to measure urinary amylase as an early marker of rejection has not been substantiated. However, there may be a selective role for bladder drainage in 'high risk' pancreases. Also, without a clear-cut metabolic benefit to PVD over SVD, it remains the surgeon's choice as to which method to use.

Origin and influence of coal mine drainage on streams of the United States

USGS Publications Warehouse

Powell, J.D.

1988-01-01

Degradation of water quality related to oxidation of iron disulfide minerals associated with coal is a naturally occurring process that has been observed since the late seventeenth century, many years before commencement of commercial coal mining in the United States. Disturbing coal strata during mining operations accelerates this natural deterioration of water quality by exposing greater surface areas of reactive minerals to the weathering effects of the atmosphere, hydrosphere, and biosphere. Degraded water quality in the temperate eastern half of the United States is readily detected because of the low mineralization of natural water. Maps are presented showing areas in the eastern United States where concentrations of chemical constituents in water affected by coal mining (pH, dissolved sulfate, total iron, total manganese) exceed background values and indicate effects of coal mining. Areas in the East most affected by mine drainage are in western Pennsylvania, southern Ohio, western Maryland, West Virginia, southern Illinois, western Kentucky, northern Missouri, and southern Iowa. Effects of coal mining on water quality in the more arid western half of the United States are more difficult to detect because of the high degree of mineralization of natural water. Normal background concentrations of constituents are not useful in evaluating effects of coal mine drainage on streams in the more arid West. Three approaches to reduce the effects of coal mining on water quality are: (1) exclusion of oxygenated water from reactive minerals, (2) neutralization of the acid produced, (3) retardation of acid-producing bacteria population in spoil material, by application of detergents that do not produce byproducts requiring disposal. These approaches can be used to help prevent further degradation of water quality in streams by future mining. ?? 1988 Springer-Verlag New York Inc.

Lymphatic drainage patterns of oral maxillary tumors: Approachable locations of sentinel lymph nodes mainly at the cervical neck level.

PubMed

Boeve, Koos; Schepman, Kees-Pieter; Vegt, Bert van der; Schuuring, Ed; Roodenburg, Jan L; Brouwers, Adrienne H; Witjes, Max J

2017-03-01

There is debate if the lymphatic drainage pattern of oral maxillary cancer is to the retropharyngeal lymph nodes or to the cervical lymph nodes. Insight in drainage patterns is important for the indication for neck treatment. The purpose of this study was to identify the lymphatic drainage pattern of oral maxillary cancer via preoperative lymphoscintigraphy. Eleven consecutive patients with oral maxillary cancer treated in our center between December 1, 2012, and April 22, 2016 were studied. Sentinel lymph nodes identified by preoperative lymphoscintigraphy after injection of 99m Tc-nanocolloid and by intraoperative detection using a γ-probe, were surgically removed and histopathologically examined. In 10 patients, sentinel lymph nodes were detected and harvested at cervical levels I, II, or III in the neck. In 2 patients, a parapharyngeal sentinel lymph node was detected. One of the harvested sentinel lymph nodes (1/19) was tumor positive. This study suggests the likelihood of 73% of exclusively cervical level I to III sentinel lymph nodes in oral maxillary cancer. © 2016 Wiley Periodicals, Inc. Head Neck 39: 486-491, 2017. © 2016 Wiley Periodicals, Inc.

Comparison of closed-chest drainage with rib resection closed drainage for treatment of chronic tuberculous empyema

PubMed Central

Fang, Yong; Xiao, Heping; Hu, Haili

2018-01-01

Background This study aimed to compare the efficacy of closed-chest drainage with rib resection closed drainage of chronic tuberculous empyema. Methods This retrospective study reviewed 86 patients with tuberculous empyema in Shanghai Pulmonary Hospital from August 2010 to November 2015. Among these included patients, 22 patients received closed-chest drainage, and 64 patients received rib resection closed drainage. Results The results showed that after intercostal chest closed drain treatment, 2 (9.09%) patients were recovery, 13 (59.09%) patients had significantly curative effect, 6 (27.27%) patients had partly curative effect, and 1 (4.55%) patient had negative effect. After treatment of rib resection closed drainage, 9 (14.06%) patients were successfully recovery, 31 (48.44%) patients had significantly curative effect, 19 (29.69%) patients had partly curative effect, and 5 (7.81%) patients had negative effect. There was no significant difference in the curative effect (P>0.05), while the average catheterization time of rib resection closed drainage (130.05±13.12 days) was significant longer than that (126.14±36.84 days) in course of intercostal chest closed drain (P<0.05). Conclusions This study had demonstrated that closed-chest drainage was an effective procedure for treating empyema in young patients. It was less invasive than rib resection closed drainage and was associated with less severe pain. We advocated closed-chest drainage for the majority of young patients with empyema, except for those with other diseases. PMID:29600066

Tracking surface and subsurface lakes on the Greenland Ice Sheet using Sentinel-1 SAR and Landsat-8 OLI imagery

NASA Astrophysics Data System (ADS)

Miles, Katie; Willis, Ian; Benedek, Corinne; Williamson, Andrew; Tedesco, Marco

2017-04-01

Supraglacial lakes (SGLs) on the Greenland Ice Sheet (GrIS) are an important component of the ice sheet's mass balance and hydrology, with their drainage affecting ice dynamics. This study uses imagery from the recently launched Sentinel-1A Synthetic Aperture Radar (SAR) to investigate SGLs in West Greenland. SAR can image through cloud and in darkness, overcoming some of the limitations of commonly used optical sensors. A semi automated algorithm is developed to detect surface lakes from Sentinel images during the 2015 summer. It generally detects water in all locations where a Landsat-8 NDWI classification (with a relatively high threshold value) detects water. A combined set of images from Landsat-8 and Sentinel-1 is used to track lake behaviour at a comparable temporal resolution to that which is possible with MODIS, but at a higher spatial resolution. A fully automated lake drainage detection algorithm is used to investigate both rapid and slow drainages for both small and large lakes through the summer. Our combined Landsat-Sentinel dataset, with a temporal resolution of three days, could track smaller lakes (mean 0.089 km2) than are resolvable in MODIS (minimum 0.125 km2). Small lake drainage events (lakes smaller than can be detected using MODIS) were found to occur at lower elevations ( 200 m) and slightly earlier in the melt season than larger events, as were slow lake drainage events compared to rapid events. The Sentinel imagery allows the analysis to be extended manually into the early winter to calculate the dates and elevations of lake freeze-through more precisely than is possible with optical imagery (mean 30 August, 1270 m mean elevation). Finally, the Sentinel imagery allows subsurface lakes (which are invisible to optical sensors) to be detected, and, for the first time, their dates of appearance and freeze-through to be calculated (mean 9 August and 7 October, respectively). These subsurface lakes occur at higher elevations than the surface lakes detected in this study (1593 m mean elevation). Sentinel imagery therefore provides great potential for tracking melting, water movement and freezing within the firn zone of the GrIS.

Effects of Autogenic Drainage on Sputum Recovery and Pulmonary Function in People with Cystic Fibrosis: A Systematic Review.

PubMed

Morgan, Kimbly; Osterling, Kristin; Gilbert, Robert; Dechman, Gail

2015-01-01

To determine the effects of short- and long-term use of autogenic drainage (AD) on pulmonary function and sputum recovery in people with cystic fibrosis (CF). The authors conducted a systematic review of randomized and quasi-randomized clinical trials in which participants were people with CF who use AD as their sole airway clearance technique. Searches in 4 databases and secondary sources using 5 key terms yielded 735 articles, of which 58 contained the terms autogenic drainage and cystic fibrosis. Ultimately, 4 studies, 2 of which were long term, were included. All measured forced expiratory volume in 1 second (FEV1) and found no change. The long-term studies were underpowered to detect change in FEV1; however, the short-term studies found a clinically significant sputum yield (≥4 g). AD has been shown to produce clinically significant sputum yields in a limited number of investigations. The effect of AD on the function of the pulmonary system remains uncertain, and questions have emerged regarding the appropriateness of FEV1 as a valid measure of airway clearance from peripheral lung regions. Further consideration should be given to the use of FEV1 as a primary measure of the effect of AD.

Effects of Autogenic Drainage on Sputum Recovery and Pulmonary Function in People with Cystic Fibrosis: A Systematic Review

PubMed Central

Osterling, Kristin; Gilbert, Robert; Dechman, Gail

2015-01-01

ABSTRACT Purpose: To determine the effects of short- and long-term use of autogenic drainage (AD) on pulmonary function and sputum recovery in people with cystic fibrosis (CF). Methods: The authors conducted a systematic review of randomized and quasi-randomized clinical trials in which participants were people with CF who use AD as their sole airway clearance technique. Results: Searches in 4 databases and secondary sources using 5 key terms yielded 735 articles, of which 58 contained the terms autogenic drainage and cystic fibrosis. Ultimately, 4 studies, 2 of which were long term, were included. All measured forced expiratory volume in 1 second (FEV1) and found no change. The long-term studies were underpowered to detect change in FEV1; however, the short-term studies found a clinically significant sputum yield (≥4 g). Conclusion: AD has been shown to produce clinically significant sputum yields in a limited number of investigations. The effect of AD on the function of the pulmonary system remains uncertain, and questions have emerged regarding the appropriateness of FEV1 as a valid measure of airway clearance from peripheral lung regions. Further consideration should be given to the use of FEV1 as a primary measure of the effect of AD. PMID:27504031

Effects of acid mine drainage on the stream ecosystem of the east fork of the Obey River, Tennessee

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

Nichols, L.E.; Bulow, F.L.

1973-01-01

The stream ecosystem of the east fork of the Obey River, Tennessee was studied from January through December 1970. Emphasis centered on water quality, macroinvertebrates, fish and aquatic flora affected by acid mine drainage. Two control stations were established within the study area, one located below the zone of pollution. A reservoir station was established to detect any neutralization occurring within Dale Hollow Reservoir below the confluence of the east fork and west fork. An area approximately 40 miles in length was found to be severely degraded by acid mine drainage. Limited macroinvertebrate populations existed within this region. Chironomus andmore » Sialis were the predominate benthic indicator organisms present in the polluted zone. Euglena mutabilis was the most abundant representative organism of the aquatic flora. This organism was found to be characteristic of acid mine pollution. Fish were recovered above and below, but not within, the zone of pollution. Fish recovered were characteristic of the type of habitat in which they were collected, being either typical stream or reservoir fish. A fish kill occurred in the east fork embayment of Dale Hollow on August 15, 1970 from acid mine drainage discharged upstream.« less

Effects of the inner droplet of double emulsions on the film drainage during a head-on collision

NASA Astrophysics Data System (ADS)

Wang, Jingtao; Jing, Hefeng; Xu, Genmiao; Wang, Xiaoyong; Duan, Zhenya

2015-07-01

As a critical stage which severely affects the final coalescence of droplets, film drainage in the collision process of two simple droplets has been deeply studied for many years. However, the collision of multiple emulsions which contain other phases (like daughter droplets or particles) has never been studied although multiple emulsions are very important in emulsion industries nowadays. In this paper, the head-on collision of two core-shell double emulsions with equal sizes is investigated through a boundary integral method to disclose the effects of the inner droplet on the film drainage. When capillary number Ca is relatively high, due to the effect of the inner droplet on the inner circulation of mother droplets, the film drainage of double emulsions includes three stages: drainage, drainage halt, and second drainage, instead of two stages for that of simple droplets: drainage and drainage halt.

Occurrence of and trends in selected sediment-associated contaminants in Caddo Lake, East Texas, 1940-2002

USGS Publications Warehouse

Wilson, Jennifer T.

2003-01-01

Bottom-sediment cores were collected from four sites in Caddo Lake in East Texas during May 2002 for analyses of radionuclides (for age dating), organochlorine pesticides, polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), and major and trace elements, and to describe the occurrence and trends of these sediment-associated contaminants. The Goose Prairie Creek and Harrison Bayou sites receive drainage from an area that includes parts of the now-closed Longhorn Army Ammunitions Plant. The mid-lake site is relatively close to dense oil and gas operations in the lake. The Carter Lake site receives minimal discharge from developed areas. Sediment age (deposition) dates represented in the cores ranged from 1940 to 2002. The only organochlorine compounds detected in all core samples were the DDT degradation products DDE or DDD, and PCB Aroclors 1242, 1254, and 1260 were detected only at the Goose Prairie Creek site. One or more of the DDE concentrations at all sites exceeded a consensus-based threshold effect concentration (on benthic biota), but none exceeded a consensus-based probable effect concentration. The Goose Prairie Creek site had significant downward trends in concentrations of organochlorine compounds, except for no trend in DDE concentrations. The Ammunitions Plant is a possible historical source of the few organochlorine compounds detected at the Goose Prairie Creek and Harrison Bayou sites. PAH concentrations at all sites were below respective threshold effect concentrations. Highest PAH concentrations at all four sites were of C2- alkylated naphthalenes. Nearly all statistically significant PAH trends in the cores were downward. On the basis of PAH source-indicator ratios, the majority of PAH compounds appear to have originated from uncombusted sources such as leaks or spills from oil and gas operations or vehicles (automobiles, boats, aircraft) in the Caddo Lake area. Concentrations of several of the eight trace elements with threshold effect concentrations and probable effect concentrations (among 26 analyzed) were above the respective threshold effect concentrations, but all, except one lead concentration at the Goose Prairie Creek site (deposited about 1961), were below respective probable effect concentrations. Among trace element concentrations at the four sites, lead and mercury were consistently relatively high at the Goose Prairie Creek site. Again the Ammunitions Plant, because of its proximity and history of industrial activities, is the suspected primary source. Statistically significant trends in trace element concentrations were mixed, but more were downward than upward. Computations to indicate the dominant source (atmospheric fallout or drainage area) of mercury to the Caddo Lake sediment core sites (except Carter Lake) indicate that about one-third of the mercury at the Goose Prairie Creek site might result from drainage area sources. No drainage area sources were indicated for the Harrison Bayou and mid-lake sites. Arsenic, cadmium, and zinc concentrations were highest at the Carter Lake site. No relation between the relatively higher trace element concentrations and any potential source of contamination in the Carter Lake drainage area (for example, oil and gas operations, a road, a boat ramp) is indicated.

A Specific Mapping Study Using Fluorescence Sentinel Lymph Node Detection in Patients with Intermediate- and High-risk Prostate Cancer Undergoing Extended Pelvic Lymph Node Dissection.

PubMed

Nguyen, Daniel P; Huber, Philipp M; Metzger, Tobias A; Genitsch, Vera; Schudel, Hans H; Thalmann, George N

2016-11-01

Sentinel lymph node (SLN) detection techniques have the potential to change the standard of surgical care for patients with prostate cancer. We performed a lymphatic mapping study and determined the value of fluorescence SLN detection with indocyanine green (ICG) for the detection of lymph node metastases in intermediate- and high-risk patients undergoing radical prostatectomy and extended pelvic lymph node dissection. A total of 42 patients received systematic or specific ICG injections into the prostate base, the midportion, the apex, the left lobe, or the right lobe. We found (1) that external and internal iliac regions encompass the majority of SLNs, (2) that common iliac regions contain up to 22% of all SLNs, (3) that a prostatic lobe can drain into the contralateral group of pelvic lymph nodes, and (4) that the fossa of Marcille also receives significant drainage. Among the 12 patients who received systematic ICG injections, 5 (42%) had a total of 29 lymph node metastases. Of these, 16 nodes were ICG positive, yielding 55% sensitivity. The complex drainage pattern of the prostate and the low sensitivity of ICG for the detection of lymph node metastases reported in our study highlight the difficulties related to the implementation of SNL techniques in prostate cancer. There is controversy about how extensive lymph node dissection (LND) should be during prostatectomy. We investigated the lymphatic drainage of the prostate and whether sentinel node fluorescence techniques would be useful to detect node metastases. We found that the drainage pattern is complex and that the sentinel node technique is not able to replace extended pelvic LND. Copyright © 2016. Published by Elsevier B.V.

Brominated flame retardants and perfluoroalkyl acids in groundwater, tile drainage, soil, and crop grain following a high application of municipal biosolids to a field.

PubMed

Gottschall, N; Topp, E; Edwards, M; Payne, M; Kleywegt, S; Lapen, D R

2017-01-01

Dewatered municipal biosolids (DMB) were applied at a rate of 22Mgdwha -1 to an agricultural field in fall 2008. Concentrations of polybrominated diphenyl ethers (PBDEs; BDE-47, -99, -100, -153, -154, -183, -197, -207, -209), other brominated flame retardants (BFRs; HBB, PBEB, DBDPE, BTBPE) and perfluoroalkyl acids (PFAAs; PFHxS, PFOS, PFDS, PFOSA, PFHpA, PFOA, PFNA, PFDA, PFUnA, PFDoA, PFTA) were monitored in tile drainage, groundwater (2m, 4m and 6m depth), soil cores (0-0.3m) pre- and post-application, DMB aggregates incorporated into the soil post-application, and in wheat (Triticum spp.) planted post-application. Several compounds were detected in soil and water pre-application and on a reference field plot. PBDEs, other BFRs and PFAAs were detected in tile drainage and 2m groundwater throughout the post-application study period; a few PBDEs were also detected sporadically at lower depths in groundwater. Some of these compounds had not been detected pre-application, while some exceeded reference field plot/pre-application levels (some significantly (p<0.05) in tile drainage); both cases indicating biosolid-based water contamination. In DMB aggregates, several PBDE congeners were found to have dissipated exponentially, with reductions >90% in many of them within 1year post-application. Exponential dissipation of other BFRs and PFAAs in DMB aggregates were not significant. No PBDEs, other BFRs, or PFAAs were detected in wheat grain. Crown Copyright © 2016. Published by Elsevier B.V. All rights reserved.

Composite fibrous glaucoma drainage implant

NASA Astrophysics Data System (ADS)

Klapstova, A.; Horakova, J.; Shynkarenko, A.; Lukas, D.

2017-10-01

Glaucoma is a frequent reason of loss vision. It is usually caused by increased intraocular pressure leading to damage of optic nerve head. This work deals with the development of fibrous structure suitable for glaucoma drainage implants (GDI). Commercially produced metallic glaucoma implants are very effective in lowering intraocular pressure. However, these implants may cause adverse events such as damage to adjacent tissue, fibrosis, hypotony or many others [1]. The aim of this study is to reduce undesirable properties of currently produced drains and improve their properties by creating of the composite fibrous drain for achieve a normal intraocular pressure. Two types of electrospinning technologies were used for the production of very small tubular implants. First type was focused for production of outer part of tubular drain and the second type of electrospinning method made the inner part of shape follows the connections of both parts. Complete implant had a special properties suitable for drainage of fluid. Morphological parameters, liquid transport tests and in-vitro cell adhesion tests were detected.

Seismicity on the western Greenland Ice Sheet: Surface fracture in the vicinity of active moulins

DOE PAGES

Carmichael, Joshua D.; Joughin, Ian; Behn, Mark D.; ...

2015-06-25

We analyzed geophone and GPS measurements collected within the ablation zone of the western Greenland Ice Sheet during a ~35 day period of the 2011 melt season to study changes in ice deformation before, during, and after a supraglacial lake drainage event. During rapid lake drainage, ice flow speeds increased to ~400% of winter values, and icequake activity peaked. At times >7 days after drainage, this seismicity developed variability over both diurnal and longer periods (~10 days), while coincident ice speeds fell to ~150% of winter values and showed nightly peaks in spatial variability. Approximately 95% of all detected seismicitymore » in the lake basin and its immediate vicinity was triggered by fracture propagation within near-surface ice (<330 m deep) that generated Rayleigh waves. Icequakes occurring before and during drainage frequently were collocated with the down flow (west) end of the primary hydrofracture through which the lake drained but shifted farther west and outside the lake basin after the drainage. We interpret these results to reveal vertical hydrofracture opening and local uplift during the drainage, followed by enhanced seismicity and ice flow on the downstream side of the lake basin. This region collocates with interferometric synthetic aperture radar-measured speedup in previous years and could reflect the migration path of the meltwater supplied to the bed by the lake. The diurnal seismic signal can be associated with nightly reductions in surface melt input that increase effective basal pressure and traction, thereby promoting elevated strain in the surficial ice.« less

Biliary drainage strategy of unresectable malignant hilar strictures by computed tomography volumetry.

PubMed

Takahashi, Ei; Fukasawa, Mitsuharu; Sato, Tadashi; Takano, Shinichi; Kadokura, Makoto; Shindo, Hiroko; Yokota, Yudai; Enomoto, Nobuyuki

2015-04-28

To identify criteria for predicting successful drainage of unresectable malignant hilar biliary strictures (UMHBS) because no ideal strategy currently exists. We examined 78 patients with UMHBS who underwent biliary drainage. Drainage was considered effective when the serum bilirubin level decreased by ≥ 50% from the value before stent placement within 2 wk after drainage, without additional intervention. Complications that occurred within 7 d after stent placement were considered as early complications. Before drainage, the liver volume of each section (lateral and medial sections of the left liver and anterior and posterior sections of the right liver) was measured using computed tomography (CT) volumetry. Drained liver volume was calculated based on the volume of each liver section and the type of bile duct stricture (according to the Bismuth classification). Tumor volume, which was calculated by using CT volumetry, was excluded from the volume of each section. Receiver operating characteristic (ROC) analysis was performed to identify the optimal cutoff values for drained liver volume. In addition, factors associated with the effectiveness of drainage and early complications were evaluated. Multivariate analysis showed that drained liver volume [odds ratio (OR) = 2.92, 95%CI: 1.648-5.197; P < 0.001] and impaired liver function (with decompensated liver cirrhosis) (OR = 0.06, 95%CI: 0.009-0.426; P = 0.005) were independent factors contributing to the effectiveness of drainage. ROC analysis for effective drainage showed cutoff values of 33% of liver volume for patients with preserved liver function (with normal liver or compensated liver cirrhosis) and 50% for patients with impaired liver function (with decompensated liver cirrhosis). The sensitivity and specificity of these cutoff values were 82% and 80% for preserved liver function, and 100% and 67% for impaired liver function, respectively. Among patients who met these criteria, the rate of effective drainage among those with preserved liver function and impaired liver function was 90% and 80%, respectively. The rates of effective drainage in both groups were significantly higher than in those who did not fulfill these criteria (P < 0.001 and P = 0.02, respectively). Drainage-associated cholangitis occurred in 9 patients (12%). A smaller drained liver volume was associated with drainage-associated cholangitis (P < 0.01). Liver volume drainage ≥ 33% in patients with preserved liver function and ≥ 50% in patients with impaired liver function correlates with effective biliary drainage in UMHBS.

Transbronchial drainage using endobronchial ultrasonography with guide sheath for lung abscess: A case report.

PubMed

Yaguchi, Daizo; Ichikawa, Motoshi; Inoue, Noriko; Kobayashi, Daisuke; Shizu, Masato; Imai, Naoyuki

2018-05-01

Lung abscess was previously treated surgically, but is now mainly treated with antibiotics and ideally with direct drainage, although postural drainage canalso be used. A chest abnormal shadow was detected in an 82-year-old man and he was referred to our department in November 2017. On chest computed tomography (CT), a low-density mass shadow was present in the left S8 segment. Lung abscess and lung cancer were considered as differential diagnoses, and treatment with sulbactam sodium/ampicillin sodium (SBT/ABPC) was first initiated for lung abscess. The etiologic agent could not be identified by sputum examination, and the abscess shadow remained. Lung abscess. Endobronchial ultrasonography with a guide sheath (EBUS-GS)-guided bronchoscopy was performed on hospital day 21 to diagnose the lesion, identify the etiologic agent if the lesion was a lung abscess, and attempt drainage. Vacuum aspiration performed in the guide sheath after the probe was placed within the lesion produced 4-5 ml of gray turbid pus, and the abscess was judged to have been drained. A subsequent pathological examination did not detect malignant cells. Klebsiella pneumoniae, Prevotella spp. was identified as the etiologic agent in bacteriological tests. Antibiotics were changed based on sensitivity test results, and drainage was similarly performed on hospital day 28. The shadow gradually improved and disappeared. Therefore, this procedure and treatment led to identification of the etiologic agent and helped with cure of the disease. Based on the basic principle of treatment for abscess using as much drainage as possible, EBUS-GS-guided transbronchial drainage may be considered to be a "new procedure" for lung abscess.

Transbronchial drainage using endobronchial ultrasonography with guide sheath for lung abscess

PubMed Central

Yaguchi, Daizo; Ichikawa, Motoshi; Inoue, Noriko; Kobayashi, Daisuke; Shizu, Masato; Imai, Naoyuki

2018-01-01

Abstract Rationale: Lung abscess was previously treated surgically, but is now mainly treated with antibiotics and ideally with direct drainage, although postural drainage canalso be used. Patient concerns: A chest abnormal shadow was detected in an 82-year-old man and he was referred to our department in November 2017. On chest computed tomography (CT), a low-density mass shadow was present in the left S8 segment. Lung abscess and lung cancer were considered as differential diagnoses, and treatment with sulbactam sodium/ampicillin sodium (SBT/ABPC) was first initiated for lung abscess. The etiologic agent could not be identified by sputum examination, and the abscess shadow remained. Diagnoses: Lung abscess. Interventions: Endobronchial ultrasonography with a guide sheath (EBUS-GS)-guided bronchoscopy was performed on hospital day 21 to diagnose the lesion, identify the etiologic agent if the lesion was a lung abscess, and attempt drainage. Vacuum aspiration performed in the guide sheath after the probe was placed within the lesion produced 4-5 ml of gray turbid pus, and the abscess was judged to have been drained. Outcomes: A subsequent pathological examination did not detect malignant cells. Klebsiella pneumoniae, Prevotella spp. was identified as the etiologic agent in bacteriological tests. Antibiotics were changed based on sensitivity test results, and drainage was similarly performed on hospital day 28. The shadow gradually improved and disappeared. Therefore, this procedure and treatment led to identification of the etiologic agent and helped with cure of the disease. Lessons: Based on the basic principle of treatment for abscess using as much drainage as possible, EBUS-GS-guided transbronchial drainage may be considered to be a “new procedure” for lung abscess. PMID:29768382

Reconnaissance investigation of water quality, bottom sediment, and biota associated with irrigation drainage in the Salton Sea area, California, 1986-87

USGS Publications Warehouse

Setmire, J.G.; Wolfe, J.C.; Stroud, R.K.

1990-01-01

Water, bottom sediment, and biota were sampled during 1986 and 1987 in the Salton Sea area to determine concentrations of trace elements and pesticides as part of the Department of Interior Irrigation Drainage Program. The sampling sites (12 water, 15 bottom sediment, and 5 biota) were located in the Coachella and Imperial Valleys. The focus of sampling was to determine the current or potential threat to the wildlife of the Salton National Wildlife Refuge from irrigation projects sponsored or operated by the Department of the Interior. Results of the investigation indicate that selenium is the major element of concern. Elevated concentrations of selenium in water were restricted to tile-drain effluent. The maximum selenium concentration of 300 microg/L was detected in a tile-drain sample, and the minimum concentration of 1 microg/L was detected in a composite sample of Salton Sea water. The median selenium concentration was 19 microg/L. In contrast to the water, the highest bottom-sediment selenium concentration of 3.3 mg/kg was in a composite sample from the Salton Sea. The selenium detected in samples of waterfowl and fish also are of concern, but, to date, no studies have been done in the Salton Sea area to determine if selenium has caused adverse biological effects. Concentrations of boron and manganese were elevated in tile-drain samples throughout the Imperial Valley. Boron concentrations in migratory waterfowl were at levels that could cause reproduction impairment. Elevated concentrations of chromium, nickel, and zinc were detected in the Whitewater River , but they were not associated with irrigation drainage. Organochlorine pesticide residues were detected in bottom sediment throughout the study area at levels approaching those measured more than 10 years ago. More detailed studies would be needed to determine if these residues are affecting the waterfowl. (USGS)

Surveying drainage culvert use by carnivores: sampling design and cost-benefit analyzes of track-pads vs. video-surveillance methods.

PubMed

Mateus, Ana Rita A; Grilo, Clara; Santos-Reis, Margarida

2011-10-01

Environmental assessment studies often evaluate the effectiveness of drainage culverts as habitat linkages for species, however, the efficiency of the sampling designs and the survey methods are not known. Our main goal was to estimate the most cost-effective monitoring method for sampling carnivore culvert using track-pads and video-surveillance. We estimated the most efficient (lower costs and high detection success) interval between visits (days) when using track-pads and also determined the advantages of using each method. In 2006, we selected two highways in southern Portugal and sampled 15 culverts over two 10-day sampling periods (spring and summer). Using the track-pad method, 90% of the animal tracks were detected using a 2-day interval between visits. We recorded a higher number of crossings for most species using video-surveillance (n = 129) when compared with the track-pad technique (n = 102); however, the detection ability using the video-surveillance method varied with type of structure and species. More crossings were detected in circular culverts (1 m and 1.5 m diameter) than in box culverts (2 m to 4 m width), likely because video cameras had a reduced vision coverage area. On the other hand, carnivore species with small feet such as the common genet Genetta genetta were detected less often using the track-pad surveying method. The cost-benefit analyzes shows that the track-pad technique is the most appropriate technique, but video-surveillance allows year-round surveys as well as the behavior response analyzes of species using crossing structures.

Understanding Lymphatic Drainage Pathways of the Ovaries to Predict Sites for Sentinel Nodes in Ovarian Cancer

PubMed Central

Kleppe, Marjolein; Kraima, Anne C.; Kruitwagen, Roy F.P.M.; Van Gorp, Toon; Smit, Noeska N.; van Munsteren, Jacoba C.; DeRuiter, Marco C.

2015-01-01

Objective In ovarian cancer, detection of sentinel nodes is an upcoming procedure. Perioperative determination of the patient’s sentinel node(s) might prevent a radical lymphadenectomy and associated morbidity. It is essential to understand the lymphatic drainage pathways of the ovaries, which are surprisingly up till now poorly investigated, to predict the anatomical regions where sentinel nodes can be found. We aimed to describe the lymphatic drainage pathways of the human ovaries including their compartmental fascia borders. Methods A series of 3 human female fetuses and tissues samples from 1 human cadaveric specimen were studied. Immunohistochemical analysis was performed on paraffin-embedded transverse sections (8 or 10 μm) using antibodies against Lyve-1, S100, and α-smooth muscle actin to identify the lymphatic endothelium, Schwann, and smooth muscle cells, respectively. Three-dimensional reconstructions were created. Results Two major and 1 minor lymphatic drainage pathways from the ovaries were detected. One pathway drained via the proper ligament of the ovaries (ovarian ligament) toward the lymph nodes in the obturator fossa and the internal iliac artery. Another pathway drained the ovaries via the suspensory ligament (infundibulopelvic ligament) toward the para-aortic and paracaval lymph nodes. A third minor pathway drained the ovaries via the round ligament to the inguinal lymph nodes. Lymph vessels draining the fallopian tube all followed the lymphatic drainage pathways of the ovaries. Conclusions The lymphatic drainage pathways of the ovaries invariably run via the suspensory ligament (infundibulopelvic ligament) and the proper ligament of the ovaries (ovarian ligament), as well as through the round ligament of the uterus. Because ovarian cancer might spread lymphogenously via these routes, the sentinel node can be detected in the para-aortic and paracaval regions, obturator fossa and surrounding internal iliac arteries, and inguinal regions. These findings support the strategy of injecting tracers in both ovarian ligaments to identify sentinel nodes. PMID:26397066

Towards monitoring surface and subsurface lakes on the Greenland Ice Sheet using Sentinel-1 SAR and Landsat-8 OLI imagery

NASA Astrophysics Data System (ADS)

Miles, Katie E.; Willis, Ian C.; Benedek, Corinne L.; Williamson, Andrew G.; Tedesco, Marco

2017-07-01

Supraglacial lakes are an important component of the Greenland Ice Sheet’s mass balance and hydrology, with their drainage affecting ice dynamics. This study uses imagery from the recently launched Sentinel-1A Synthetic Aperture Radar (SAR) satellite to investigate supraglacial lakes in West Greenland. A semi-automated algorithm is developed to detect surface lakes from Sentinel-1 images during the 2015 summer. A combined Landsat-8 and Sentinel-1 dataset, which has a comparable temporal resolution to MODIS (3 days versus daily) but a higher spatial resolution (25-40 m versus 250-500 m), is then used together with a fully-automated lake drainage detection algorithm. Rapid (< 4 days) and slow (> 4 days) drainages are investigated for both small (< 0.125 km2, the minimum size detectable by MODIS) and large (≥ 0.125 km2) lakes through the summer. Drainage events of small lakes occur at lower elevations (mean 159 m), and slightly earlier (mean 4.5 days) in the melt season than those of large lakes. The analysis is extended manually into the early winter to calculate the dates and elevations of lake freeze-through more precisely than is possible with optical imagery (mean 30 August; 1270 m mean elevation). Finally, the Sentinel-1 imagery is used to detect subsurface lakes and, for the first time, their dates of appearance and freeze-through (mean 9 August and 7 October, respectively). These subsurface lakes occur at higher elevations than the surface lakes detected in this study (mean 1593 m and 1185 m, respectively). Sentinel-1 imagery therefore provides great potential for tracking melting, water movement and freezing within both the firn zone and ablation area of the Greenland Ice Sheet.

A portable thoracic closed drainage instrument for hemopneumothorax.

PubMed

Tang, Hua; Pan, Tiewen; Qin, Xiong; Xue, Lei; Wu, Bin; Zhao, Xuewei; Sun, Guangyuan; Yuan, Xinyu; Xu, Zhifei

2012-03-01

Hemopneumothorax is a common sequelae of traumatic thoracic injury. The most effective treatment of this condition is thoracic drainage. Despite the common occurrence of this condition, available instruments are difficult to use emergently, particularly when large amounts of patients need to be drained. In the present experiment, a newly designed chest tube and thoracic closed drainage package is described and preliminarily evaluated with the goal to improve the treatment of traumatic hemopneumothorax. Twenty canines were divided into two groups. In one group, the newly designed thoracic closed drainage package was used, whereas in the other group a currently available chest tube and bottle were used. Drainage test, ultrasound examination, flushing test, and tension test were performed to evaluate the effectiveness of the drainage package. We found that the newly-designed drainage tube is as effective as the common tube when evaluated using all of the chosen methods. In addition, the package is very lightweight and portable. The newly-designed thoracic drainage package is very effective in the emergency treatment of thoracic trauma and may be more suitable for the emergency treatment of hemopneumothorax.

Population Genetics of the Eastern Hellbender (Cryptobranchus alleganiensis alleganiensis) across Multiple Spatial Scales

PubMed Central

Unger, Shem D.; Rhodes, Olin E.; Sutton, Trent M.; Williams, Rod N.

2013-01-01

Conservation genetics is a powerful tool to assess the population structure of species and provides a framework for informing management of freshwater ecosystems. As lotic habitats become fragmented, the need to assess gene flow for species of conservation management becomes a priority. The eastern hellbender (Cryptobranchus alleganiensis alleganiensis) is a large, fully aquatic paedamorphic salamander. Many populations are experiencing declines throughout their geographic range, yet the genetic ramifications of these declines are currently unknown. To this end, we examined levels of genetic variation and genetic structure at both range-wide and drainage (hierarchical) scales. We collected 1,203 individuals from 77 rivers throughout nine states from June 2007 to August 2011. Levels of genetic diversity were relatively high among all sampling locations. We detected significant genetic structure across populations (Fst values ranged from 0.001 between rivers within a single watershed to 0.218 between states). We identified two genetically differentiated groups at the range-wide scale: 1) the Ohio River drainage and 2) the Tennessee River drainage. An analysis of molecular variance (AMOVA) based on landscape-scale sampling of basins within the Tennessee River drainage revealed the majority of genetic variation (∼94–98%) occurs within rivers. Eastern hellbenders show a strong pattern of isolation by stream distance (IBSD) at the drainage level. Understanding levels of genetic variation and differentiation at multiple spatial and biological scales will enable natural resource managers to make more informed decisions and plan effective conservation strategies for cryptic, lotic species. PMID:24204565

Pesticides in streams in the Tar-Pamlico drainage basin, North Carolina, 1992-94

USGS Publications Warehouse

Woodside, Michael D.; Ruhl, Kelly E.

2001-01-01

From 1992 to 1994, 147 water samples were collected at 5 sites in the Tar-Pamlico drainage basin in North Carolina and analyzed for 46 herbicides, insecticides, and pesticide metabolites as part of the U.S. Geological Survey's National Water-Quality Assessment Program. Based on a common adjusted detection limit of 0.01 microgram per liter, the most frequently detected herbicides were metolachlor (84 percent), atrazine (78 percent), alachlor (72 percent), and prometon (57 percent). The insecticides detected most frequently were carbaryl (12 percent), carbofuran (7 percent), and diazinon (4 percent). Although the pesticides with the highest estimated uses generally were the compounds detected most frequently, there was not a strong correlation between estimated use and detection frequency. The development of statistical correlations between pesticide use and detection frequency was limited by the lack of information on pesticides commonly applied in urban and agricultural areas, such as prometon, chlorpyrifos, and diazinon, and the small number of basins included in this study. For example, prometon had the fourth highest detection frequency, but use information was not available. Nevertheless, the high detection frequency of prometon indicates that nonagricultural uses also contribute to pesticide levels in streams in the Tar-Pamlico drainage basin.Concentrations of the herbicides atrazine, alachlor, and trifluralin varied seasonally, with elevated concentrations generally occurring in the spring, during and immediately following application periods, and in the summer. Seasonal concentration patterns were less evident for prometon, diazinon, and chlorpyrifos. Alachlor is the only pesticide detected in concentrations that exceeded current (2000) drinking-water standards.

Progress in the application of landform analysis in studies of semiarid erosion

USGS Publications Warehouse

Schumm, Stanley Alfred; Hadley, R.F.

1961-01-01

The analysis of topographic and hydrologic data gathered during studies of erosion in semiarid areas of Western United States show the following relation: (a) Mean annual sediment yield from small drainage basins is related to a ratio of basin relief to length; (b) mean annual runoff from small drainage basins is related to drainage density; (c) mean annual sediment yield per unit area decreases with increase in drainage area; (d) the form of some convex hill slopes is related to surficial creep; (e) asymmetry of drainage basins, including differences in hill-slope erosion and drainage density, is related to microclimatic variations on slopes of diverse exposure; .(f) the cutting of discontinuous gullies is closely related to steepening by deposition of the semiarid valley floor; (g) aggradation in ephemeral streams seems to be most prevalent in reaches where the ratio of contributing drainage area to channel length is relatively small; and (h) streamchannel shape, expressed as a width-depth ratio, is related to the percentage of silt-clay in bed and bank alluvium. The above relations cannot be detected without measurement of terrain characteristics. They further indicate the importance of quantitative terrain analysis in studies of erosion.

Effects of long-term drainage on microbial community composition vary between peatland types

NASA Astrophysics Data System (ADS)

Urbanová, Zuzana; Barta, Jiri

2016-04-01

Peatlands represent an important reservoir of carbon, but their functioning can be threatened by water level drawdown caused by climate or land use change. Knowledge of how microbial communities respond to long-term drainage in different peatland types could help improve predictions of the effect of climate change on these ecosystems. We investigated the effect of long-term drainage on microbial community composition in bog, fen and spruce swamp forests (SSF) in the Sumava Mountains (Czech Republic), using high-throughput barcoded sequencing, in relation to peat biochemical properties. Longterm drainage had substantial effects, which depended strongly on peatland type, on peat biochemical properties and microbial community composition. The effect of drainage was most apparent on fen, followed by SSF, and lowest on bog. Long-term drainage led to lower pH, reduced peat decomposability and increased bulk density, which was reflected by reduced microbial activity. Bacterial diversity decreased and Acidobacteria became the dominant phylum on drained sites, reflecting a convergence in bacterial community composition across peatlands after long-term drainage. The archaeal communities changed very strongly and became similar across drained peatlands. Overall, the characteristic differences between distinct peatland types under natural conditions were diminished by long-term drainage. Bog represented a relatively resilient system while fen seemed to be very sensitive to environmental changes.

The effective mitigation of greenhouse gas emissions from rice paddies without compromising yield by early-season drainage.

PubMed

Islam, Syed Faiz-Ul; van Groenigen, Jan Willem; Jensen, Lars Stoumann; Sander, Bjoern Ole; de Neergaard, Andreas

2018-01-15

Global rice production systems face two opposing challenges: the need to increase production to accommodate the world's growing population while simultaneously reducing greenhouse gas (GHG) emissions. Adaptations to drainage regimes are one of the most promising options for methane mitigation in rice production. Whereas several studies have focused on mid-season drainage (MD) to mitigate GHG emissions, early-season drainage (ED) varying in timing and duration has not been extensively studied. However, such ED periods could potentially be very effective since initial available C levels (and thereby the potential for methanogenesis) can be very high in paddy systems with rice straw incorporation. This study tested the effectiveness of seven drainage regimes varying in their timing and duration (combinations of ED and MD) to mitigate CH 4 and N 2 O emissions in a 101-day growth chamber experiment. Emissions were considerably reduced by early-season drainage compared to both conventional continuous flooding (CF) and the MD drainage regime. The results suggest that ED+MD drainage may have the potential to reduce CH 4 emissions and yield-scaled GWP by 85-90% compared to CF and by 75-77% compared to MD only. A combination of (short or long) ED drainage and one MD drainage episode was found to be the most effective in mitigating CH 4 emissions without negatively affecting yield. In particular, compared with CF, the long early-season drainage treatments LE+SM and LE+LM significantly (p<0.01) decreased yield-scaled GWP by 85% and 87% respectively. This was associated with carbon being stabilised early in the season, thereby reducing available C for methanogenesis. Overall N 2 O emissions were small and not significantly affected by ED. It is concluded that ED+MD drainage might be an effective low-tech option for small-scale farmers to reduce GHG emissions and save water while maintaining yield. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Effects of anthropogenic heavy metal contamination on litter decomposition in streams - A meta-analysis.

PubMed

Ferreira, Verónica; Koricheva, Julia; Duarte, Sofia; Niyogi, Dev K; Guérold, François

2016-03-01

Many streams worldwide are affected by heavy metal contamination, mostly due to past and present mining activities. Here we present a meta-analysis of 38 studies (reporting 133 cases) published between 1978 and 2014 that reported the effects of heavy metal contamination on the decomposition of terrestrial litter in running waters. Overall, heavy metal contamination significantly inhibited litter decomposition. The effect was stronger for laboratory than for field studies, likely due to better control of confounding variables in the former, antagonistic interactions between metals and other environmental variables in the latter or differences in metal identity and concentration between studies. For laboratory studies, only copper + zinc mixtures significantly inhibited litter decomposition, while no significant effects were found for silver, aluminum, cadmium or zinc considered individually. For field studies, coal and metal mine drainage strongly inhibited litter decomposition, while drainage from motorways had no significant effects. The effect of coal mine drainage did not depend on drainage pH. Coal mine drainage negatively affected leaf litter decomposition independently of leaf litter identity; no significant effect was found for wood decomposition, but sample size was low. Considering metal mine drainage, arsenic mines had a stronger negative effect on leaf litter decomposition than gold or pyrite mines. Metal mine drainage significantly inhibited leaf litter decomposition driven by both microbes and invertebrates, independently of leaf litter identity; no significant effect was found for microbially driven decomposition, but sample size was low. Overall, mine drainage negatively affects leaf litter decomposition, likely through negative effects on invertebrates. Copyright © 2015 Elsevier Ltd. All rights reserved.

Tile Drainage Density Reduces Groundwater Travel Times and Compromises Riparian Buffer Effectiveness.

PubMed

Schilling, Keith E; Wolter, Calvin F; Isenhart, Thomas M; Schultz, Richard C

2015-11-01

Strategies to reduce nitrate-nitrogen (nitrate) pollution delivered to streams often seek to increase groundwater residence time to achieve measureable results, yet the effects of tile drainage on residence time have not been well documented. In this study, we used a geographic information system groundwater travel time model to quantify the effects of artificial subsurface drainage on groundwater travel times in the 7443-ha Bear Creek watershed in north-central Iowa. Our objectives were to evaluate how mean groundwater travel times changed with increasing drainage intensity and to assess how tile drainage density reduces groundwater contributions to riparian buffers. Results indicate that mean groundwater travel times are reduced with increasing degrees of tile drainage. Mean groundwater travel times decreased from 5.6 to 1.1 yr, with drainage densities ranging from 0.005 m (7.6 mi) to 0.04 m (62 mi), respectively. Model simulations indicate that mean travel times with tile drainage are more than 150 times faster than those that existed before settlement. With intensive drainage, less than 2% of the groundwater in the basin appears to flow through a perennial stream buffer, thereby reducing the effectiveness of this practice to reduce stream nitrate loads. Hence, strategies, such as reconnecting tile drainage to buffers, are promising because they increase groundwater residence times in tile-drained watersheds. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Effect of abdominopelvic abscess drain size on drainage time and probability of occlusion

PubMed Central

Rotman, Jessica A.; Getrajdman, George I.; Maybody, Majid; Erinjeri, Joseph P.; Yarmohammadi, Hooman; Sofocleous, Constantinos T.; Solomon, Stephen B.; Boas, F. Edward

2016-01-01

Background The purpose of this study is to determine whether larger abdominopelvic abscess drains reduce the time required for abscess resolution, or the probability of tube occlusion. Methods 144 consecutive patients who underwent abscess drainage at a single institution were reviewed retrospectively. Results: Larger initial drain size did not reduce drainage time, drain occlusion, or drain exchanges (p>0.05). Subgroup analysis did not find any type of collection that benefitted from larger drains. A multivariate model predicting drainage time showed that large collections (>200 ml) required 16 days longer drainage time than small collections (<50 ml). Collections with a fistula to bowel required 17 days longer drainage time than collections without a fistula. Initial drain size and the viscosity of the fluid in the collection had no significant effect on drainage time in the multivariate model. Conclusions 8 F drains are adequate for initial drainage of most serous and serosanguineous collections. 10 F drains are adequate for initial drainage of most purulent or bloody collections. PMID:27634422

[Application research of presacral space drainage tube combined with subcutaneous vacuum pressure suction in the laparoscopic-assisted abdominoperineal resection].

PubMed

Chen, Liqi; Zeng, Changqing; Chi, Liangjie; Huang, Liangxiang; Li, Jiandang

2017-08-25

To study the management for the perineal incision after laparoscopic-assisted abdominoperineal resection for rectal cancer. Clinical data of 87 patients undergoing laparoscopic Miles operation for lower rectal cancer from June 2009 to February 2014 were collected and studied. Presacral space drainage group: presacral space drainage tube was applied in 42 patients. Combined drainage group: presacral space drainage tube combined with subcutaneous vacuum pressure suction was applied in 45 cases. In combined drainage group, except the presacral drainage tube, another drainage tube was placed subcutaneously and connected to a negative pressure ball, which was fixed on the lateral anterior of perineal wound by the further incision and drainage. After subcutaneous tube was placed for 2 weeks, as drainage fluid was limpid and <15 ml/d for 3 days, meanwhile no obvious pelvic fluid was detected by ultrasound, and the wound healed quite well without redness and edema, then the subcutaneous tube with the negative pressure ball could be removed. There were 51 males and 36 females with the mean age of 26-78(56.9±10.8) years old. The laparoscopic Miles operation was successfully completed in all the cases without death and complications. The drainage tube was placed for 4-13(8.0±2.5) days in presacral space drainage group, and for 4-14(6.7±2.4) days in combined drainage group. The subcutaneous tube was placed for 14-24(15.8±3.0) days. The primary healing rate of perineal wound in presacral space drainage group and combined drainage group was 66.7%(28/42) and 91.1%(41/45) respectively, while the perineal wound infection rate was 21.4%(9/42) and 4.4%(2/45) respectively, whose differences between two groups were both significant (χ 2 =7.911, P=0.005 and χ 2 =5.674, P=0.017). Presacral space drainage tube combined with subcutaneous vacuum pressure suction in laparoscopic-assisted abdominoperineal resection for rectal cancer has better efficacy and lower infection rate for perineal incision, which is worth wide application.

Direct lymphangiography as treatment option of lymphatic leakage: indications, outcomes and role in patient's management.

PubMed

Gruber-Rouh, Tatjana; Naguib, Nagy N N; Lehnert, Thomas; Harth, Marc; Thalhammer, Axel; Beeres, Martin; Tsaur, Igor; Hammersting, Renate; Wichmann, Julian L; Vogl, Thomas J; Jacobi, Volkmar

2014-12-01

To evaluate the effectiveness of lymphography as a minimally invasive treatment option of lymphatic leakage in terms of local control and to investigate which parameters influence the success rate. This retrospective study protocol was approved by the ethic committee. Patient history, imaging data, therapeutic options and follow-up were recorded and retrospectively analyzed. Between June 1998 and February 2013, 71 patients (m:w = 42:29, mean age, 52.4; range 42–75 years) with lymphatic leakage in form of lymphatic fistulas (n = 37), lymphocele (n = 11), chylothorax (n = 13) and chylous ascites (n = 10)underwent lymphography. Sixty-four patients (90.1%) underwent successful lymphography while lymphography failed in 7 cases. Therapeutic success was evaluated and correlated to the volume of lymphatic leakage and to the volume of the applied iodized oil. Signs of leakage or contrast extravasation were directly detected in 64 patients. Of 64 patients, 45 patients (70.3%) were treated and cured after lymphography. Based on the lymphography findings, 19 patients (29.7%) underwent surgical intervention with a completely occlusion of lymphatic leakage. The lymphatic leak could be completely occluded in 96.8% of patients when the lymphatic drainage volume was less than 200 mL/day (n = 33). Even when lymphatic drainage was higher than 200 mL/day (n = 31),therapeutic lymphography was still successful in 58.1% of the patients. Lymphography is an effective, minimally invasive method in the detection and treatment of lymphatic leakage. The volume of lymphatic drainage per day is a significant predictor of the therapeutic success rate. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Monitoring the effect of restoration measures in Indonesian peatlands by radar satellite imagery.

PubMed

Jaenicke, J; Englhart, S; Siegert, F

2011-03-01

In the context of the ongoing climate change discussions the importance of peatlands as carbon stores is increasingly recognised in the public. Drainage, deforestation and peat fires are the main reasons for the release of huge amounts of carbon from peatlands. Successful restoration of degraded tropical peatlands is of high interest due to their huge carbon store and sequestration potential. The blocking of drainage canals by dam building has become one of the most important measures to restore the hydrology and the ecological function of the peat domes. This study investigates the capability of using multitemporal radar remote sensing imagery for monitoring the hydrological effects of these measures. The study area is the former Mega Rice Project area in Central Kalimantan, Indonesia, where peat drainage and forest degradation is especially intense. Restoration measures started in July 2004 by building 30 large dams until June 2008. We applied change detection analysis with more than 80 ENVISAT ASAR and ALOS PALSAR images, acquired between 2004 and 2009. Radar signal increases of up to 1.36 dB show that high frequency multitemporal radar satellite imagery can be used to detect an increase in peat soil moisture after dam construction, especially in deforested areas with a high density of dams. Furthermore, a strong correlation between cross-polarised radar backscatter coefficients and groundwater levels above -50 cm was found. Monitoring peatland rewetting and quantifying groundwater level variations is important information for vegetation re-establishment, fire hazard warning and making carbon emission mitigation tradable under the voluntary carbon market or REDD (Reducing Emissions from Deforestation and Degradation) mechanism. Copyright © 2010 Elsevier Ltd. All rights reserved.

[Effect of epidural drainage and dural tenting suture on epidural hematoma in 145 cases of craniotomy].

PubMed

Zhao, Jie; Liu, Zhixiong; Liu, Yunsheng; Liu, Jinfang; Fang, Wenhua; Rao, Yihua; Yang, Liang; Yuan, Xianrui

2010-03-01

To evaluate the efficacy of dural tenting suture and epidural drainage in craniotomy. In 145 cases of intracranial lesions, dural tenting suture and epidural drainage were performed to prevent epidural hematoma. Postoperative computed tomography (CT) showed no epidural hematoma required surgery in both groups. Both dural tenting suture and epidural drainage are effective in preventing epidural hematoma. Hemostasis is the key step. Dural tenting suture without epidural drainage relieves psychological stress. It decreases the risk of intracranial infection and avoids some unusual complications.

Adaptation Options for Land Drainage Systems Towards Sustainable Agriculture and Environment: A Czech Perspective

NASA Astrophysics Data System (ADS)

Kulhavý, Zbyněk; Fučík, Petr

2015-04-01

In this paper, issues of agricultural drainage systems are introduced and discussed from the views of their former, current and future roles and functioning in the Czech Republic (CR). A methodologically disparate survey was done on thirty-nine model localities in CR with different intensity and state of land drainage systems, aimed at description of commonly occurred problems and possible adaptations of agricultural drainage as perceived by farmers, land owners, landscape managers or by protective water management. The survey was focused on technical state of drainage, fragmentation of land ownership within drained areas as well as on possible conflicts between agricultural and environmental interests in a landscape. Achieved results confirmed that there is obviously an increasing need to reassess some functions of prevailingly single-purpose agricultural drainage systems. Drainage intensity and detected unfavourable technical state of drainage systems as well as the risks connected with the anticipated climate change from the view of possible water scarcity claims for a complex solution. An array of adaptation options for agricultural drainage systems is presented, aiming at enhancement of water retention time and improvement of water quality. It encompasses additional flow-controlling measures on tiles or ditches, or facilities for making selected parts of a drainage system inoperable in order to retain or slow down the drainage runoff, to establish water accumulation zones and to enhance water self-cleaning processes. However, it was revealed that the question of landowner parcels fragmentation on drained land in CR would dramatically complicate design and realization of these measures. Presented solutions and findings are propounded with a respect to contemporary and future state policies and international strategies for sustainable agriculture, water management and environment.

Omitting chest tube drainage after thoracoscopic major lung resection.

PubMed

Ueda, Kazuhiro; Hayashi, Masataro; Tanaka, Toshiki; Hamano, Kimikazu

2013-08-01

Absorbable mesh and fibrin glue applied to prevent alveolar air leakage contribute to reducing the length of chest tube drainage, length of hospitalization and the rate of pulmonary complications. This study investigated the feasibility of omitting chest tube drainage in selected patients undergoing thoracoscopic major lung resection. Intraoperative air leakages were sealed with fibrin glue and absorbable mesh in patients undergoing thoracoscopic major lung resection. The chest tube was removed just after tracheal extubation if no air leakages were detected in a suction-induced air leakage test, which is an original technique to confirm pneumostasis. Patients with bleeding tendency or extensive thoracic adhesions were excluded. Chest tube drainage was omitted in 29 (58%) of 50 eligible patients and was used in 21 (42%) on the basis of suction-induced air leakage test results. Male gender and compromised pulmonary function were significantly associated with the failure to omit chest tube drainage (both, P < 0.05). Regardless of omitting the chest tube drainage, there were no adverse events during hospitalization, such as subcutaneous emphysema, pneumothorax, pleural effusion or haemothorax, requiring subsequent drainage. Furthermore, there was no prolonged air leakage in any patients: The mean length of chest tube drainage was only 0.9 days. Omitting the chest tube drainage was associated with reduced pain on the day of the operation (P = 0.046). The refined strategy for pneumostasis allowed the omission of chest tube drainage in the majority of patients undergoing thoracoscopic major lung resection without increasing the risk of adverse events, which may contribute to a fast-track surgery.

A case study examining the efficacy of drainage setbacks for limiting effects to wetlands in the Prairie Pothole Region, USA

USGS Publications Warehouse

Tangen, Brian; Finocchiaro, Raymond

2017-01-01

The enhancement of agricultural lands through the use of artificial drainage systems is a common practice throughout the United States, and recently the use of this practice has expanded in the Prairie Pothole Region. Many wetlands are afforded protection from the direct effects of drainage through regulation or legal agreements, and drainage setback distances typically are used to provide a buffer between wetlands and drainage systems. A field study was initiated to assess the potential for subsurface drainage to affect wetland surface-water characteristics through a reduction in precipitation runoff, and to examine the efficacy of current U.S. Department of Agriculture drainage setback distances for limiting these effects. Surface-water levels, along with primary components of the catchment water balance, were monitored over 3 y at four seasonal wetland catchments situated in a high-relief terrain (7–11% slopes). During the second year of the study, subsurface drainage systems were installed in two of the catchments using drainage setbacks, and the drainage discharge volumes were monitored. A catchment water-balance model was used to assess the potential effect of subsurface drainage on wetland hydrology and to assess the efficacy of drainage setbacks for mitigating these effects. Results suggest that overland precipitation runoff can be an important component of the seasonal water balance of Prairie Pothole Region wetlands, accounting on average for 34% (19–49%) or 45% (39–49%) of the annual (includes snowmelt runoff) or seasonal (does not include snowmelt) input volumes, respectively. Seasonal (2014–2015) discharge volumes from the localized drainage systems averaged 81 m3 (31–199 m3), and were small when compared with average combined inputs of 3,745 m3 (1,214–6,993 m3) from snowmelt runoff, direct precipitation, and precipitation runoff. Model simulations of reduced precipitation runoff volumes as a result of subsurface drainage systems showed that ponded wetland surface areas were reduced by an average of 590 m2 (141–1,787 m2), or 24% (3–46%), when no setbacks were used (drainage systems located directly adjacent to wetland). Likewise, wetland surface areas were reduced by an average of 141 m2 (23–464 m2), or 7% (1–28%), when drainage setbacks (buffer) were used. In totality, the field data and model simulations suggest that the drainage setbacks should reduce, but not eliminate, impacts to the water balance of the four wetlands monitored in this study that were located in a high-relief terrain. However, further study is required to assess the validity of these conclusions outside of the limited parameters (e.g., terrain, weather, soils) of this study and to examine potential ecological effects of altered wetland hydrology.

Effect of abdominopelvic abscess drain size on drainage time and probability of occlusion.

PubMed

Rotman, Jessica A; Getrajdman, George I; Maybody, Majid; Erinjeri, Joseph P; Yarmohammadi, Hooman; Sofocleous, Constantinos T; Solomon, Stephen B; Boas, F Edward

2017-04-01

The purpose of this study is to determine whether larger abdominopelvic abscess drains reduce the time required for abscess resolution or the probability of tube occlusion. 144 consecutive patients who underwent abscess drainage at a single institution were reviewed retrospectively. Larger initial drain size did not reduce drainage time, drain occlusion, or drain exchanges (P > .05). Subgroup analysis did not find any type of collection that benefitted from larger drains. A multivariate model predicting drainage time showed that large collections (>200 mL) required 16 days longer drainage time than small collections (<50 mL). Collections with a fistula to bowel required 17 days longer drainage time than collections without a fistula. Initial drain size and the viscosity of the fluid in the collection had no significant effect on drainage time in the multivariate model. 8 F drains are adequate for initial drainage of most serous and serosanguineous collections. 10 F drains are adequate for initial drainage of most purulent or bloody collections. Copyright © 2016 Elsevier Inc. All rights reserved.

PASSIVE TREATMENT OF ACID ROCK DRAINAGE FROM A SUBSURFACE MINE

EPA Science Inventory

Acidic, metal-contaminated drainages are a critical problem facing many areas of the world. Acid rock drainage results when metal sulfide minerals, particularly pyrite, are oxidized by exposure to oxygen and water. The deleterious effects of these drainages on receiving streams a...

The Seepage Simulation of Single Hole and Composite Gas Drainage Based on LB Method

NASA Astrophysics Data System (ADS)

Chen, Yanhao; Zhong, Qiu; Gong, Zhenzhao

2018-01-01

Gas drainage is the most effective method to prevent and solve coal mine gas power disasters. It is very important to study the seepage flow law of gas in fissure coal gas. The LB method is a simplified computational model based on micro-scale, especially for the study of seepage problem. Based on fracture seepage mathematical model on the basis of single coal gas drainage, using the LB method during coal gas drainage of gas flow numerical simulation, this paper maps the single-hole drainage gas, symmetric slot and asymmetric slot, the different width of the slot combined drainage area gas flow under working condition of gas cloud of gas pressure, flow path diagram and flow velocity vector diagram, and analyses the influence on gas seepage field under various working conditions, and also discusses effective drainage method of the center hole slot on both sides, and preliminary exploration that is related to the combination of gas drainage has been carried on as well.

Effects of underground mining and mine collapse on the hydrology of selected basins in West Virginia

USGS Publications Warehouse

Hobba, William A.

1993-01-01

The effects of underground mining and mine collapse on areal hydrology were determined at one site where the mined bed of coal lies above major streams and at two sites where the bed of coal lies below major streams. Subsidence cracks observed at land surface generally run parallel to predominant joint sets in the rocks. The mining and subsidence cracks increase hydraulic conductivity and interconnection of water-bearing rock units, which in turn cause increased infiltration of precipitation and surface water, decreased evapotranspiration, and higher base flows in some small streams. Water levels in observation wells in mined areas fluctuate as much as 100 ft annually. Both gaining and losing streams are found in mined areas. Mine pumpage and drainage can cause diversion of water underground from one basin to another. Areal and single-well aquifer tests indicated that near-surface rocks have higher transmissivity in a mine-subsided basin than in unmined basins. Increased infiltration and circulation through shallow subsurface rocks increase dissolved mineral loads in streams, as do treated and untreated contributions from mine pumpage and drainage. Abandoned and flooded underground mines make good reservoirs because of their increased transmissivity and storage. Subsidence cracks were not detectable by thermal imagery, but springs and seeps were detectable.

PleurAlert: an augmented chest drainage system with electronic sensing, automated alerts and internet connectivity.

PubMed

Leeson, Cory E; Weaver, Robert A; Bissell, Taylor; Hoyer, Rachel; McClain, Corinne; Nelson, Douglas A; Samosky, Joseph T

2012-01-01

We have enhanced a common medical device, the chest tube drainage container, with electronic sensing of fluid volume, automated detection of critical alarm conditions and the ability to automatically send alert text messages to a nurse's cell phone. The PleurAlert system provides a simple touch-screen interface and can graphically display chest tube output over time. Our design augments a device whose basic function dates back 50 years by adding technology to automate and optimize a monitoring process that can be time consuming and inconvenient for nurses. The system may also enhance detection of emergency conditions and speed response time.

Nasal septal abscess caused by anaerobic bacteria of oral flora.

PubMed

Hyo, Yukiyoshi; Fukushima, Hisaki; Harada, Tamotsu; Hara, Hirotaka

2018-06-07

Although nasal septal abscess (NSA) was formerly common, it has become rare since the development of antibiotics. NSA, if left untreated, can lead to intracranial complications such as meningitis and eventually result in saddle-nose deformity. NSA often occurs after injury, and indigenous skin bacteria such as Staphylococcus aureus are frequently detected. We treated a patient who had injured the upper alveolus in a fall on the stairs and developed NSA two weeks later. Anaerobic bacteria, including Veillonella parvula and Peptostreptococcus sp., were detected. Symptoms were relieved by needle and incisional drainage. Our patient represents a very rare case of NSA in terms of the cause of onset and the detected bacteria. Early drainage can result in good outcomes. Copyright © 2018 Elsevier B.V. All rights reserved.

Prairie Pothole Region wetlands and subsurface drainage systems: Key factors for determining drainage setback distances

USGS Publications Warehouse

Tangen, Brian; Wiltermuth, Mark T.

2018-01-01

Use of agricultural subsurface drainage systems in the Prairie Pothole Region of North America continues to increase, prompting concerns over potential negative effects to the Region's vital wetlands. The U.S. Fish and Wildlife Service protects a large number of wetlands through conservation easements that often utilize standard lateral setback distances to provide buffers between wetlands and drainage systems. Because of a lack of information pertaining to the efficacy of these setback distances for protecting wetlands, information is required to support the decision making for placement of subsurface drainage systems adjacent to wetlands. We used qualitative graphical analyses and data comparisons to identify characteristics of subsurface drainage systems and wetland catchments that could be considered when assessing setback distances. We also compared setback distances with catchment slope lengths to determine if they typically exclude drainage systems from the catchment. We demonstrated that depth of a subsurface drainage system is a key factor for determining drainage setback distances. Drainage systems located closer to the surface (shallow) typically could be associated with shorter lateral setback distances compared with deeper systems. Subsurface drainage systems would be allowed within a wetland's catchment for 44–59% of catchments associated with wetland conservation easements in North Dakota. More specifically, results suggest that drainage setback distances generally would exclude drainage systems from catchments of the smaller wetlands that typically have shorter slopes in the adjacent upland contributing area. For larger wetlands, however, considerable areas of the catchment would be vulnerable to drainage that may affect wetland hydrology. U.S. Fish and Wildlife Service easements are associated with > 2,000 km2 of wetlands in North Dakota, demonstrating great potential to protect these systems from drainage depending on policies for installing subsurface drainage systems on these lands. The length of slope of individual catchments and depth of subsurface drainage systems could be considered when prescribing drainage setback distances and assessing potential effects to wetland hydrology. Moreover, because of uncertainties associated with the efficacy of standard drainage setback distances, exclusion of subsurface drainage systems from wetland catchments would be ideal when the goal is to protect wetlands.

Tunnel Face Stability and the Effectiveness of Advance Drainage Measures in Water-Bearing Ground of Non-uniform Permeability

NASA Astrophysics Data System (ADS)

Zingg, Sara; Anagnostou, Georg

2018-01-01

Non-uniform permeability may result in complex hydraulic head fields with potentially very high hydraulic gradients close to the tunnel face, which may be adverse for stability depending on the ground strength. Pore pressure relief by drainage measures in advance of the tunnel excavation improves stability, but the effectiveness of drainage boreholes may be low in the case of alternating aquifers and aquitards. This paper analyses the effects of hydraulic heterogeneity and advance drainage quantitatively by means of limit equilibrium computations that take account of the seepage forces acting upon the ground in the vicinity the tunnel face. The piezometric field is determined numerically by means of steady-state, three-dimensional seepage flow analyses considering the heterogeneous structure of the ground and a typical advance drainage scheme consisting of six axial boreholes drilled from the tunnel face. A suite of stability analyses was carried out covering a wide range of heterogeneity scales. The computational results show the effect of the orientation, thickness, location, number and permeability ratio of aquifers and aquitards and provide valuable indications about potentially critical situations, the effectiveness of advance drainage and the adequate arrangement of drainage boreholes. The paper shows that hydraulic heterogeneity results in highly variable face behaviour, even if the shear strength of the ground is constant along the alignment, but ground behaviour is considerably less variable in the presence of advance drainage measures.

Effective and efficient agricultural drainage pipe mapping with UAS thermal infrared imagery: a case study

USDA-ARS?s Scientific Manuscript database

Effective and efficient methods are needed to map agricultural subsurface drainage systems. Visible (VIS), near infrared (NIR), and/or thermal infrared (TIR) imagery obtained by unmanned aircraft systems (UAS) may provide a means for determining drainage pipe locations. Preliminary UAS surveys wit...

Regional Assessment of Human Fecal Contamination in Southern California Coastal Drainages

PubMed Central

Cao, Yiping; Raith, Meredith R.; Smith, Paul D.; Griffith, John F.; Weisberg, Stephen B.; Schriewer, Alexander; Sheldon, Andrew; Crompton, Chris; Gregory, Jason; Guzman, Joe; Othman, Laila; Manasjan, Mayela; Choi, Samuel; Rapoport, Shana; Steele, Syreeta; Nguyen, Tommy; Yu, Xueyuan

2017-01-01

Host-associated genetic markers that allow for fecal source identification have been used extensively as a diagnostic tool to determine fecal sources within watersheds, but have not been used in routine monitoring to prioritize remediation actions among watersheds. Here, we present a regional assessment of human marker prevalence among drainages that discharge to the U.S. southern California coast. Approximately 50 samples were analyzed for the HF183 human marker from each of 22 southern California coastal drainages under summer dry weather conditions, and another 50 samples were targeted from each of 23 drainages during wet weather. The HF183 marker was ubiquitous, detected in all but two sites in dry weather and at all sites during wet weather. However, there was considerable difference in the extent of human fecal contamination among sites. Similar site ranking was produced regardless of whether the assessment was based on frequency of HF183 detection or site average HF183 concentration. However, site ranking differed greatly between dry and wet weather. Site ranking also differed greatly when based on enterococci, which do not distinguish between pollution sources, vs. HF183, which distinguishes higher risk human fecal sources from other sources, indicating the additional value of the human-associated marker as a routine monitoring tool. PMID:28777324

Regional Assessment of Human Fecal Contamination in Southern California Coastal Drainages.

PubMed

Cao, Yiping; Raith, Meredith R; Smith, Paul D; Griffith, John F; Weisberg, Stephen B; Schriewer, Alexander; Sheldon, Andrew; Crompton, Chris; Amenu, Geremew G; Gregory, Jason; Guzman, Joe; Goodwin, Kelly D; Othman, Laila; Manasjan, Mayela; Choi, Samuel; Rapoport, Shana; Steele, Syreeta; Nguyen, Tommy; Yu, Xueyuan

2017-08-04

Host-associated genetic markers that allow for fecal source identification have been used extensively as a diagnostic tool to determine fecal sources within watersheds, but have not been used in routine monitoring to prioritize remediation actions among watersheds. Here, we present a regional assessment of human marker prevalence among drainages that discharge to the U.S. southern California coast. Approximately 50 samples were analyzed for the HF183 human marker from each of 22 southern California coastal drainages under summer dry weather conditions, and another 50 samples were targeted from each of 23 drainages during wet weather. The HF183 marker was ubiquitous, detected in all but two sites in dry weather and at all sites during wet weather. However, there was considerable difference in the extent of human fecal contamination among sites. Similar site ranking was produced regardless of whether the assessment was based on frequency of HF183 detection or site average HF183 concentration. However, site ranking differed greatly between dry and wet weather. Site ranking also differed greatly when based on enterococci, which do not distinguish between pollution sources, vs. HF183, which distinguishes higher risk human fecal sources from other sources, indicating the additional value of the human-associated marker as a routine monitoring tool.

Spectral contrast-enhanced optical coherence tomography for improved detection of tumor microvasculature and functional imaging of lymphatic drainage

NASA Astrophysics Data System (ADS)

SoRelle, Elliott D.; Liba, Orly; Sen, Debasish; de la Zerda, Adam

2017-03-01

Optical Coherence Tomography (OCT) is well-suited to study in vivo dynamics of blood circulation and lymphatic flow because of the technique's combination of rapid image acquisition, micron spatial resolution, and penetration depth in turbid tissues. However, OCT has been historically constrained by a dearth of contrast agents that are readily distinguished from the strong scattering intrinsic to biological tissues. In this study, we demonstrate large gold nanorods (LGNRs) as optimized contrast agents for OCT. LGNRs produce 32-fold greater backscattering than GNRs previously tested for contrast-enhanced OCT. Furthermore, LGNRs exhibit 110-fold stronger spectral signal than conventional GNRs when coupled with custom spectral detection algorithms. This signal enhancement enables picomolar OCT detection sensitivity in vivo and single-particle detection against optically-clear backgrounds. Moreover, the ability to synthesize LGNRs with tunable spectral peaks provides a viable platform for multiplexed imaging studies. To explore the advantages of LGNRs as OCT contrast agents, we implemented them for noninvasive 3D imaging of tumor blood supply and active lymphatic drainage in mice. Spectral detection of LGNRs enabled 100% improvement in imaging depth for detecting microvasculature (vessels 20 μm in diameter) in U87MG glioblastoma xenografts in mice pinnae. We also demonstrated our approach's ability to map the spatial dependence of lymph drainage and flow directionality within lymphatic capillaries. Using LGNRs with distinct spectra, we further identified the functional states of individual lymphatic valves in vivo. Thus, this approach provides a powerful new platform for functional imaging that may be extended for future molecular imaging studies with OCT.

Effect of subsurface drainage on streamflow in an agricultural headwater watershed

USDA-ARS?s Scientific Manuscript database

Artificial drainage, also known as subsurface or tile drainage is paramount to sustaining crop production agriculture in the poorly-drained, humid regions of the world. Hydrologic assessments of individual plots and fields with tile drainage are becoming common; however, a major void exists in our u...

Sleep Deprivation Attack Detection in Wireless Sensor Network

NASA Astrophysics Data System (ADS)

Bhattasali, Tapalina; Chaki, Rituparna; Sanyal, Sugata

2012-02-01

Deployment of sensor network in hostile environment makes it mainly vulnerable to battery drainage attacks because it is impossible to recharge or replace the battery power of sensor nodes. Among different types of security threats, low power sensor nodes are immensely affected by the attacks which cause random drainage of the energy level of sensors, leading to death of the nodes. The most dangerous type of attack in this category is sleep deprivation, where target of the intruder is to maximize the power consumption of sensor nodes, so that their lifetime is minimized. Most of the existing works on sleep deprivation attack detection involve a lot of overhead, leading to poor throughput. The need of the day is to design a model for detecting intrusions accurately in an energy efficient manner. This paper proposes a hierarchical framework based on distributed collaborative mechanism for detecting sleep deprivation torture in wireless sensor network efficiently. Proposed model uses anomaly detection technique in two steps to reduce the probability of false intrusion.

Modeling of subglacial hydrological development following rapid supraglacial lake drainage.

PubMed

Dow, C F; Kulessa, B; Rutt, I C; Tsai, V C; Pimentel, S; Doyle, S H; van As, D; Lindbäck, K; Pettersson, R; Jones, G A; Hubbard, A

2015-06-01

The rapid drainage of supraglacial lakes injects substantial volumes of water to the bed of the Greenland ice sheet over short timescales. The effect of these water pulses on the development of basal hydrological systems is largely unknown. To address this, we develop a lake drainage model incorporating both (1) a subglacial radial flux element driven by elastic hydraulic jacking and (2) downstream drainage through a linked channelized and distributed system. Here we present the model and examine whether substantial, efficient subglacial channels can form during or following lake drainage events and their effect on the water pressure in the surrounding distributed system. We force the model with field data from a lake drainage site, 70 km from the terminus of Russell Glacier in West Greenland. The model outputs suggest that efficient subglacial channels do not readily form in the vicinity of the lake during rapid drainage and instead water is evacuated primarily by a transient turbulent sheet and the distributed system. Following lake drainage, channels grow but are not large enough to reduce the water pressure in the surrounding distributed system, unless preexisting channels are present throughout the domain. Our results have implications for the analysis of subglacial hydrological systems in regions where rapid lake drainage provides the primary mechanism for surface-to-bed connections. Model for subglacial hydrological analysis of rapid lake drainage eventsLimited subglacial channel growth during and following rapid lake drainagePersistence of distributed drainage in inland areas where channel growth is limited.

Modeling of subglacial hydrological development following rapid supraglacial lake drainage

PubMed Central

Dow, C F; Kulessa, B; Rutt, I C; Tsai, V C; Pimentel, S; Doyle, S H; van As, D; Lindbäck, K; Pettersson, R; Jones, G A; Hubbard, A

2015-01-01

The rapid drainage of supraglacial lakes injects substantial volumes of water to the bed of the Greenland ice sheet over short timescales. The effect of these water pulses on the development of basal hydrological systems is largely unknown. To address this, we develop a lake drainage model incorporating both (1) a subglacial radial flux element driven by elastic hydraulic jacking and (2) downstream drainage through a linked channelized and distributed system. Here we present the model and examine whether substantial, efficient subglacial channels can form during or following lake drainage events and their effect on the water pressure in the surrounding distributed system. We force the model with field data from a lake drainage site, 70 km from the terminus of Russell Glacier in West Greenland. The model outputs suggest that efficient subglacial channels do not readily form in the vicinity of the lake during rapid drainage and instead water is evacuated primarily by a transient turbulent sheet and the distributed system. Following lake drainage, channels grow but are not large enough to reduce the water pressure in the surrounding distributed system, unless preexisting channels are present throughout the domain. Our results have implications for the analysis of subglacial hydrological systems in regions where rapid lake drainage provides the primary mechanism for surface-to-bed connections. Key Points Model for subglacial hydrological analysis of rapid lake drainage events Limited subglacial channel growth during and following rapid lake drainage Persistence of distributed drainage in inland areas where channel growth is limited PMID:26640746

A Meta-Analysis of the Effect of Preoperative Biliary Stenting on Patients With Obstructive Jaundice

PubMed Central

Sun, Chengyi; Yan, Guirong; Li, Zhiming; Tzeng, Chi-Meng

2014-01-01

Abstract The goal of this study was to systematically review the effects of biliary stenting on postoperative morbidity and mortality of patients with obstructive jaundice. PubMed, Embase, Cochrane Library, and other relevant databases were searched by computer and manually for published and unpublished studies on the impact of preoperative biliary drainage on patients with obstructive jaundice from 2000 to the present day. Two investigators independently selected the studies according to the inclusion and exclusion criteria, extracted the data, and assessed the quality of the selected studies. Meta-analysis was performed to compare postoperative morbidity and mortality of patients between the drainage and nondrainage groups. Compared with the nondrainage group, the overall mortality, overall morbidity, infectious morbidity, incidence of wound infection, intra-abdominal abscess, pancreatic fistulas, bile leak, and delayed gastric emptying in the drainage group were not significantly different. Compared with the nondrainage group, the drainage group had a drainage time of <4 weeks with an increased overall morbidity by 7% to 23%; however, the overall morbidity of the drainage group with a drainage time >4 weeks was not significantly different. Compared with the nondrainage group, the overall mortality of the drainage group using metal stents and plastic stents as internal drainage devices was reduced by 0.5% to 6%, whereas that of the drainage group using plastic stent devices was not significantly different. In summary, preoperative drainage should be applied selectively. The drainage time should be >4 weeks, and metal stents should be used for internal drainage. PMID:25474436

The effect of drainage tube on bleeding and prognosis after total knee arthroplasty: a prospective cohort study.

PubMed

Liu, Xiao-Han; Fu, Pei-Liang; Wang, Shi-Ying; Yang, Ya-Juan; Lu, Gen-Di

2014-04-23

To evaluate the effect of drainage tube on prognosis after total knee arthroplasty (TKA) and explore an effective treatment with favorable prognosis. In a prospective study, 18 patients with TKA for the first time were included and randomly divided into three groups, group A (no placement of drainage tube), group B (negative pressure drainage), and group C (4 h clamping drainage). Intraoperative and postoperative blood loss, operation time, and the drainage volume were recorded and analyzed. Arthrocele, ecchymosis, and range of motion (ROM) were examined postoperatively. The degree of pain was scored by Visual Analog Scale (VAS) after 6, 12, and 24 h of operation. The complications were examined and HSS (hospital for special surgery) knee score was taken during the follow-up period. There was no significant difference in operation time, total blood loss, intraoperative blood loss, and VAS score among three groups. Meanwhile, the hidden blood loss in group B was significantly decreased compared with group A (P = 0.0015). The postoperative drainage volume of group B was significantly increased compared with group C (P = 0.0002). No drainage increased the rate of arthrocele and ecchymosis. Compared with group A, ROM after 3 days of operation in groups B and C was significantly increased (P = 0.0357, P = 0.0372, respectively). During follow-up study, no deep infection or deep venous thrombosis was found. After TKA, early clamping of the drainage tube reduced the bleeding loss without adverse effect on prognosis, which might be useful for clinical application in future.

[Research on the application of "H shaped" single-tube double-lumen drainage tube in the treatment of chronic subdural hematoma].

PubMed

Sun, T; Jiang, Z Q; Zhang, S J; Lou, F Y; Zhang, T; Han, Y; Zheng, X L

2016-04-05

To explore the effect of chronic subdural hematoma external drainage surgery using self-made "H shaped" flush type single-tube double-lumen drainage tube. There were 56 cases chosen from the First Affiliated Hospital of Bengbu Medical College between Jan 2013 and Aug 2015. These patients with unilateral chronic subdural hematoma requiring surgery to place drilling external drainage catheter were randomly divided into group A (21 cases, using self-made single-tube double lumen "H shaped" drainage tube) and group B (35 cases, traditional silicone drainage tube), then the residual liquid volume after drainage on the first day, the days that the tube stay in body and the residual fluid volume after removing the tube were compared between the two groups. The residual liquid volume after drainage on the first day in group A was (23±15)ml, in group B was (31±15)ml. The days that the tube stay in body in group A was (2.7±1.0)d, in group B was (3.3±1.1)d, the two groups had statistical differences (P<0.05). The residual fluid volume after removing the tube in group A was (13±7) ml, in group B was (16±8)ml, but the data in these two groups had no significantly statistical differences (P>0.05). The effect of self-made "H shaped" flush type single-tube double-lumen drainage tube in the drainage of chronic subdural hematoma drainage is good, with short tube stay in the body; therefore, it is a safe and effective way to treat chronic subdural hematoma, and is worthy of clinical application.

Randomized, controlled pilot study comparing large-volume paracentesis using wall suction and traditional glass vacuum bottle methods.

PubMed

Konerman, Monica A; Price, Jennifer; Torres, Dawn; Li, Zhiping

2014-09-01

Large-volume paracentesis (LVP) can be time and labor intensive depending on the amount of ascites removed and the method of drainage. Wall suction has been adopted as the preferred method of drainage at many centers, though the safety and benefits of this technique have not been formally evaluated. The primary objective of this study was to define the cost and time savings of wall suction over the traditional glass vacuum bottle method for ascites drainage. The secondary objective was to compare the safety profile and patient satisfaction using these two techniques. We conducted a randomized, controlled pilot study of the wall suction versus vacuum bottle methods for LVP in hospitalized patients. All LVPs were performed under ultrasound guidance by a single proceduralist. Patients with at least 4 liters removed received 25% intravenous albumin, 8 g/liter fluid removed. Demographic, clinical characteristics, and procedure details were recorded. Laboratory and hemodynamic data were recorded for 24 h prior to and 24-48 h post LVP. An electronic chart review was conducted to evaluate procedure-related complications. Data were compared using Fisher's exact test, t test, or Mann-Whitney U test. Thirty-four patients were randomized to wall suction at 200 mmHg (n = 17) or glass vacuum bottle drainage (n = 17). Wall suction was significantly faster and less costly than vacuum bottle drainage (7 versus 15 min, p = 0.002; $4.59 versus $12.73, p < 0.001). There were no differences in outcomes at 24 and 48 h post LVP, or at 60-day follow up. Performing LVP using wall suction resulted in significantly shorter procedure time and supply cost savings. There were no differences in outcomes between the groups, suggesting equivalent safety, though larger studies powered to detect small differences are needed. Given its efficiency, convenience, and cost effectiveness, wall suction may be a superior method of ascites drainage for LVP.

Prolonged Drainage and Intrapericardial Bleomycin Administration for Cardiac Tamponade Secondary to Cancer-Related Pericardial Effusion

PubMed Central

Numico, Gianmauro; Cristofano, Antonella; Occelli, Marcella; Sicuro, Marco; Mozzicafreddo, Alessandro; Fea, Elena; Colantonio, Ida; Merlano, Marco; Piovano, Pierluigi; Silvestris, Nicola

2016-01-01

Abstract Malignant pericardial effusion (MPE) is a serious complication of several cancers. The most commonly involved solid tumors are lung and breast cancer. MPE can give rise to the clinical picture of cardiac tamponade, a life threatening condition that needs immediate drainage. While simple pericardiocentesis allows resolution of the symptoms, MPE frequently relapses unless further procedures are performed. Prolonged drainage, talcage with antineoplastic agents, or surgical creation of a pleuro-pericardial window are the most commonly suggested ones. They all result in MPE resolution and high rates of long-term control. Patients suitable for further systemic treatments can have a good prognosis irrespective of the pericardial site of disease. We prospectively enrolled patients with cardiac tamponade treated with prolonged drainage associated with Bleomycin administration. Twenty-two consecutive patients with MPE and associated signs of hemodynamical compromise underwent prolonged drainage and subsequent Bleomycin administration. After injection of 100 mg lidocaine hydrochloride, 10 mg Bleomycin was injected into the pericardial space. The catheter was clumped for 48 h and then reopened. Removal was performed when the drainage volume was <25 mL daily. Twelve patients (54%) achieved complete response and 9 (41%) a partial response. Only 1 (5%) had a treatment failure and underwent a successful surgical procedure. Acute toxicity was of a low degree and occurred in 7 patients (32%). It consisted mainly in thoracic pain and supraventricular arrhythmia. The 1-year pericardial effusion progression-free survival rate was 74.0% (95% confidence interval [CI]: 51.0–97.3). At a median follow-up of 75 months, a pericardial progression was detected in 4 patients (18%). One- and two-year overall survival rates were 33.9% (95% CI: 13.6–54.2) and 14.5% (95% CI: 0.0–29.5), respectively, with lung cancer patients having a shorter survival than breast cancer patients. The worst prognosis, however, was shown in patients not suitable for systemic treatments, irrespective of the site of the primary tumor. Prolonged drainage and intrapericardial Bleomycin is a safe and effective treatment, which should be considered as first choice at least in patients suitable for active systemic treatment. PMID:27082564

Response of maize yield, nitrate leaching, and soil nitrogen to pig slurry combined with mineral nitrogen.

PubMed

Yagüe, María R; Quílez, Dolores

2010-01-01

The application of pig (Sus scrofa) slurry (PS) is a common fertilization practice that may affect nitrate concentrations and loads in drainage and receiving water bodies. To protect water resources, many agricultural areas are being designated as vulnerable to nitrate contamination, and there is a need for scientific data aiming at reducing nitrate exports from these vulnerable zones by optimizing N fertilization strategies. The objective of this work, conducted in drainage lysimeters in a 4-yr monoculture maize (Zea mays L.) crop, is to assess the effects of four fertilization strategies combining PS (30, 60, 90, and 120 t ha(-1)) and mineral N on yield, changes in soil mineral N, and concentration and mass of nitrate in drainage waters. Grain yield was not affected by treatments in the four experimental years, nor was the soil mineral N at the end of the experiment. Effects of fertilization strategies on nitrate concentration and mass in drainage waters were detected only after 3 yr of repeated PS applications. The mass of nitrate leached over the 4 yr was positively related to the total amount of N applied, either organic or mineral. In year 2003, precipitation in spring reduced N availability for the crop in treatments with rates > or = 60 t PS ha(-1). The N-budget revealed that the transport pathways for 25% of N inputs to the system are unknown. The presowing application of pig slurry at 30 t ha(-1) complemented with mineral N at side-dressing, was the most efficient from an environmental standpoint (4-yr average of 145 kg grain yield kg(-1) N leached).

Vegetated agricultural drainage ditches for the mitigation of pyrethroid-associated runoff.

PubMed

Bennett, Erin R; Moore, Matthew T; Cooper, Charles M; Smith, Sammie; Shields, F Douglas; Drouillard, Ken G; Schulz, Ralf

2005-09-01

Drainage ditches are indispensable components of the agricultural production landscape. A benefit of these ditches is contaminant mitigation of agricultural storm runoff. This study determined bifenthrin and lambda-cyhalothrin (two pyrethroid insecticides) partitioning and retention in ditch water, sediment, and plant material as well as estimated necessary ditch length required for effective mitigation. A controlled-release runoff simulation was conducted on a 650-m vegetated drainage ditch in the Mississippi Delta, USA. Bifenthrin and lambda-cyhalothrin were released into the ditch in a water-sediment slurry. Samples of water, sediment, and plants were collected and analyzed for pyrethroid concentrations. Three hours following runoff initiation, inlet bifenthrin and lambda-cyhalothrin water concentrations ranged from 666 and 374 microg/L, respectively, to 7.24 and 5.23 microg/L at 200 m downstream. No chemical residues were detected at the 400-m sampling site. A similar trend was observed throughout the first 7 d of the study where water concentrations were elevated at the front end of the ditch (0-25 m) and greatly reduced by the 400-m sampling site. Regression formulas predicted that bifenthrin and lambda-cyhalothrin concentrations in ditch water were reduced to 0.1% of the initial value within 280 m. Mass balance calculations determined that ditch plants were the major sink and/or sorption site responsible for the rapid aqueous pyrethroid dissipation. By incorporating vegetated drainage ditches into a watershed management program, agriculture can continue to decrease potential non-point source threats to downstream aquatic receiving systems. Overall results of this study illustrate that aquatic macrophytes play an important role in the retention and distribution of pyrethroids in vegetated agricultural drainage ditches.

Dissolved free and combined amino acids in surface runoff and drainage waters from drained and undrained grassland under different fertilizer management.

PubMed

Hawkins, Jane M B; Scholefield, David; Braven, Jim

2006-08-15

Organic matter is a valuable resource on which the sustainability and productivity of soils relies heavily. Thus, it is important to understand the mechanisms for the loss of organic compounds from soil. It is also essential to determine how these losses can be minimized, especially those resulting from anthropogenic activity. Grazed grassland lysimeters (1 hectare) were used to examine the contribution and distribution patterns of dissolved free and combined amino acids to dissolved organic nitrogen and carbon in surface runoff and drainage waters from a grassland soil over three winter drainage periods. The waters were collected from soils beneath drained and undrained permanent ryegrass swards, receiving 0 and 280 kg ha(-1) year(-1) mineral nitrogen (N) input. Total dissolved free amino acid (DFAA) and dissolved combined amino acid (DCAA) concentrations ranged between 1.9 nM and 6.1 microM and between 1.3 and 87 microM, respectively. Although addition of mineral N fertilizer increased both DFAA and DCAA concentrations in waters, there was no detectable effect of soil hydrology or fertilizer addition on distribution patterns.

Genetic structure of Columbia River redband trout populations in the Kootenai River drainage, Montana, revealed by microsatellite and allozyme loci

USGS Publications Warehouse

Knudsen, K.-L.; Muhlfeld, C.C.; Sage, G.K.; Leary, R.F.

2002-01-01

We describe the genetic divergence among 10 populations of redband trout Oncorhynchus mykiss gairdneri from the upper Columbia River drainage. Resident redband trout from two watersheds in the Kootenai River drainage and hatchery stocks of migratory Kamloops redband trout from Kootenay Lake, British Columbia, were analyzed using allele frequency data from microsatellite and allozyme loci. The Kamloops populations have significantly different allele frequencies from those of the Kootenai River drainage. Of the total genetic variation detected in the resident redband trout, 40.7% (microsatellites) and 15.5% (allozymes) were due to differences between populations from the two Kootenai River watersheds. The divergence among populations within each watershed, however, was less than 3.5% with both techniques. Our data indicate that watershed-specific broodstocks of redband trout are needed by fisheries managers for reintroduction or the supplementation of populations at risk of extinction.

Rapid reaccumulation of hydrometra after drainage at embryo transfer in patients with hydrosalpinx.

PubMed

Hinckley, Mary D; Milki, Amin A

2003-11-01

To report the occurrence and management of hydrometra at the time of scheduled embryo transfer in two patients who underwent drainage of hydrosalpinges at oocyte retrieval. Case report. University IVF clinic. Two patients with hydrosalpinges visible on ultrasonography who deferred tubal surgery. Although no fluid was seen at the time of oocyte retrieval, hydrometra was noticed and drained before planned embryo transfer (ET). Reoccurrence of hydrometra after drainage. Rapid reaccumulation of hydrometra despite drainage was seen in both patients, one of whom had reoccurrence in 1 hour. Embryo transfer was deferred until after tubal surgery, and all embryos were cryopreserved. In patients with hydrosalpinges, ultrasonography before ET is useful to detect newly developed hydrometra. Aspiration of the uterine fluid is unlikely to help because of rapid reaccumulation of hydrometra. Cryopreservation of the embryos for future transfer after the hydrosalpinx is removed or ligated is recommended.

Image-Guided Transvesicular Drainage of Pelvic Fluid Collections: A Safe and Effective Alternative Approach.

PubMed

Ayyagari, Raj R; Yeh, Cliff; Arici, Melih; Mojibian, Hamid; Reiner, Eric; Pollak, Jeffrey S

2016-05-01

To evaluate the safety and efficacy of percutaneous transvesicular drainage of pathologic pelvic fluid collections, a series of 15 patients who underwent 16 transvesicular drainage catheter placements was retrospectively reviewed. All patients had collections suspicious for infection that were posterior to the bladder or superior to the bladder behind loops of bowel, and were otherwise inaccessible. All 15 collections were percutaneously accessed via the bladder with standard drainage catheters. All collections resolved completely with no complications. Percutaneous transvesicular drainage was a safe and effective technique in this series, and can be considered when no direct percutaneous access routes are available. Copyright © 2016 SIR. Published by Elsevier Inc. All rights reserved.

Comparison of Suction Versus Nonsuction Drainage After Lung Resections: A Prospective Randomized Trial.

PubMed

Gocyk, Wojciech; Kużdżał, Jarosław; Włodarczyk, Janusz; Grochowski, Zbigniew; Gil, Tomasz; Warmus, Janusz; Kocoń, Piotr; Talar, Piotr; Obarski, Piotr; Trybalski, Łukasz

2016-10-01

Sufficiently large, prospective randomized trials comparing suction drainage and nonsuction drainage are lacking. The aim of the present study was to compare the effects of suction drainage and nonsuction drainage on the postoperative course in patients who have undergone lung resection. This prospective, randomized trial included patients undergoing different types of lung resections. On the day of surgery, suction drainage at -20 cm H2O was used. On the morning of the first postoperative day, patients, in whom the pulmonary parenchyma was fully reexpanded, were randomized in the ratio of 1:1. Patients assigned to group A continued with suction drainage, while those assigned to group B underwent nonsuction drainage. The study included 254 patients, with 127 patients in each group. The drainage volumes were 1098.8 mL and 814.4 mL in groups A and B, respectively (p = 0.0014). The times to chest tube removal were 5.61 days and 4.49 days in groups A and B, respectively (p = 0.0014). Prolonged air leakage occurred in 5.55% of patients in group A and in 0.7% of patients in group B (p = 0.032), and asymptomatic residual air spaces were noted in 0.8% of patients in group A and 9.4% of patients in group B (p = 0.0018). Nonsuction drainage is more effective than suction drainage with regard to drainage volume, drainage duration, and incidence of persistent air leakage. However, it is associated with a higher incidence of asymptomatic residual air spaces. Copyright © 2016 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

Effect of viscosity on tear drainage and ocular residence time.

PubMed

Zhu, Heng; Chauhan, Anuj

2008-08-01

An increase in residence time of dry eye medications including artificial tears will likely enhance therapeutic benefits. The drainage rates and the residence time of eye drops depend on the viscosity of the instilled fluids. However, a quantitative understanding of the dependence of drainage rates and the residence time on viscosity is lacking. The current study aims to develop a mathematical model for the drainage of Newtonian fluids and also for power-law non-Newtonian fluids of different viscosities. This study is an extension of our previous study on the mathematical model of tear drainage. The tear drainage model is modified to describe the drainage of Newtonian fluids with viscosities higher than the tear viscosity and power-law non-Newtonian fluids with rheological parameters obtained from fitting experimental data in literature. The drainage rate through canaliculi was derived from the modified drainage model and was incorporated into a tear mass balance to calculate the transients of total solute quantity in ocular fluids and the bioavailability of instilled drugs. For Newtonian fluids, increasing the viscosity does not affect the drainage rate unless the viscosity exceeds a critical value of about 4.4 cp. The viscosity has a maximum impact on drainage rate around a value of about 100 cp. The trends are similar for shear thinning power law fluids. The transients of total solute quantity, and the residence time agrees at least qualitatively with experimental studies. A mathematical model has been developed for the drainage of Newtonian fluids and power-law fluids through canaliculi. The model can quantitatively explain different experimental observations on the effect of viscosity on the residence of instilled fluids on the ocular surface. The current study is helpful for understanding the mechanism of fluid drainage from the ocular surface and for improving the design of dry eye treatments.

Endoscopic ultrasound-guided transmural drainage of postoperative pancreatic collections.

PubMed

Tilara, Amy; Gerdes, Hans; Allen, Peter; Jarnagin, William; Kingham, Peter; Fong, Yuman; DeMatteo, Ronald; D'Angelica, Michael; Schattner, Mark

2014-01-01

Pancreatic leak is a major cause of morbidity after pancreatectomy. Traditionally, peripancreatic fluid collections have been managed by percutaneous or operative drainage. Data for endoscopic ultrasound (EUS)-guided drainage of postoperative fluid collections are limited. Here we report on the safety, efficacy, and timing of EUS-guided drainage of postoperative peripancreatic collections. This is a retrospective review of 31 patients who underwent EUS-guided drainage of fluid collections after pancreatic resection. Technical success was defined as successful transgastric deployment of at least one double pigtail plastic stent. Clinical success was defined as resolution of the fluid collection on follow-up CT scan and resolution of symptoms. Early drainage was defined as initial transmural stent placement within 30 days after surgery. Endoscopic ultrasound-guided drainage was performed effectively with a technical success rate of 100%. Clinical success was achieved in 29 of 31 patients (93%). Nineteen of the 29 patients (65%) had complete resolution of their symptoms and collection with the first endoscopic procedure. Repeat drainage procedures, including some with necrosectomy, were required in the remaining 10 patients, with eventual resolution of collection and symptoms. Two patients who did not achieve durable clinical success required percutaneous drainage by interventional radiology. Seventeen (55%) of 31 patients had successful early drainage completed within 30 days of their operation. Endoscopic ultrasound-guided drainage of fluid collections after pancreatic resection is safe and effective. Early drainage (<30 days) of postoperative pancreatic fluid collections was not associated with increased complications in this series. Copyright © 2014 American College of Surgeons. Published by Elsevier Inc. All rights reserved.

Utilizing ERTS imagery to detect plant diseases and nutrient deficiencies, soil types and soil moisture levels

NASA Technical Reports Server (NTRS)

Parks, W. L. (Principal Investigator); Sewell, J. I.; Hilty, J. W.; Rennie, J. C.

1973-01-01

The author has identified the following significant results. The delineation of soil associations and detection of drainage patterns, erosion and sedimentation through the use of ERTS-1 imagery are shown. Corn blight and corn virus could not be detected from ERTS-1 and detection of forest composition was at a very low probability.

The effect of drainage tube on bleeding and prognosis after total knee arthroplasty: a prospective cohort study

PubMed Central

2014-01-01

Background To evaluate the effect of drainage tube on prognosis after total knee arthroplasty (TKA) and explore an effective treatment with favorable prognosis. Methods In a prospective study, 18 patients with TKA for the first time were included and randomly divided into three groups, group A (no placement of drainage tube), group B (negative pressure drainage), and group C (4 h clamping drainage). Intraoperative and postoperative blood loss, operation time, and the drainage volume were recorded and analyzed. Arthrocele, ecchymosis, and range of motion (ROM) were examined postoperatively. The degree of pain was scored by Visual Analog Scale (VAS) after 6, 12, and 24 h of operation. The complications were examined and HSS (hospital for special surgery) knee score was taken during the follow-up period. Results There was no significant difference in operation time, total blood loss, intraoperative blood loss, and VAS score among three groups. Meanwhile, the hidden blood loss in group B was significantly decreased compared with group A (P = 0.0015). The postoperative drainage volume of group B was significantly increased compared with group C (P = 0.0002). No drainage increased the rate of arthrocele and ecchymosis. Compared with group A, ROM after 3 days of operation in groups B and C was significantly increased (P = 0.0357, P = 0.0372, respectively). During follow-up study, no deep infection or deep venous thrombosis was found. Conclusion After TKA, early clamping of the drainage tube reduced the bleeding loss without adverse effect on prognosis, which might be useful for clinical application in future. PMID:24755244

Evaluation of the short- and long-term effectiveness and safety of fully covered self-expandable metal stents for drainage of pancreatic fluid collections: results of a Spanish nationwide registry.

PubMed

Vazquez-Sequeiros, Enrique; Baron, Todd H; Pérez-Miranda, Manuel; Sánchez-Yagüe, Andres; Gornals, Joan; Gonzalez-Huix, Ferran; de la Serna, Carlos; Gonzalez Martin, Juan Angel; Gimeno-Garcia, Antonio Z; Marra-Lopez, Carlos; Castellot, Ana; Alberca, Fernando; Fernandez-Urien, Ignacio; Aparicio, Jose Ramon; Legaz, Maria Luisa; Sendino, Oriol; Loras, Carmen; Subtil, Jose Carlos; Nerin, Juan; Perez-Carreras, Mercedes; Diaz-Tasende, Jose; Perez, Gustavo; Repiso, Alejandro; Vilella, Angels; Dolz, Carlos; Alvarez, Alberto; Rodriguez, Santiago; Esteban, Jose Miguel; Juzgado, Diego; Albillos, Agustin

2016-09-01

Initial reports suggest that fully covered self-expandable metal stents (FCSEMSs) may be better suited for drainage of dense pancreatic fluid collections (PFCs), such as walled-off pancreatic necrosis. The primary aim was to analyze the effectiveness and safety of FCSEMSs for drainage of different types of PFCs in a large cohort. The secondary aim was to investigate which type of FCSEMS is superior. This was a retrospective, noncomparative review of a nationwide database involving all hospitals in Spain performing EUS-guided PFC drainage. From April 2008 to August 2013, all patients undergoing PFC drainage with an FCSEMS were included in a database. The main outcome measurements were technical success, short-term (2 weeks) and long-term (6 months) effectiveness, adverse events, and need for surgery. The study included 211 patients (pseudocyst/walled-off pancreatic necrosis, 53%/47%). The FCSEMSs used were straight biliary (66%) or lumen-apposing (34%). Technical success was achieved in 97% of patients (95% confidence interval [CI], 93%-99%). Short-term- and long-term clinical success was obtained in 94% (95% CI, 89%-97%) and 85% (95% CI, 79%-89%) of patients, respectively. Adverse events occurred in 21% of patients (95% CI, 16%-27%): infection (11%), bleeding (7%), and stent migration and/or perforation (3%). By multivariate analysis, patient age (>58 years) and previous failed drainage were the most important factors associated with negative outcome. An FCSEMS is effective and safe for PFC drainage. Older patients with a history of unsuccessful drainage are more likely to fail EUS-guided drainage. The type of FCSEMS does not seem to influence patient outcome. Copyright © 2016 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.

Red rubber bulb, cheap and effective vacuum drainage.

PubMed

Vatanasapt, V; Areemit, S; Jeeravipoolvarn, P; Kuyyakanond, T; Kuptarnond, C

1989-04-01

Red rubber bulbs have been used for vacuum drainage in head, neck, breast and several other operations by the authors since 1975 quite effectively without any major problems. The vacuum pressure of the red rubber bulbs was found to be higher than the expensive commercially available vacuum wound drainage device. The question of remaining old blood and infective microorganisms inside the reservoir for the reused ones were tested by the manual cleaning process and the standard sterile technique using steam under increased pressure (autoclave). The result is quite satisfactory. We encourage the use of this cheap and effective (made in Thailand) vacuum wound drainage in Thai hospitals and Thai medical schools.

North Branch Potomac River Basin mine drainage study. Phase I. Baseline survey. Final report

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

Not Available

1977-05-06

This baseline survey of the mine drainage and related water resources of the North Branch Potomac River Basin established the extent, magnitude, and effects of coal mine drainage pollution. Alternative abatement and reclamation solutions were considered. The study included an analysis of socioeconomic and environmental conditions as related to the mine drainage problem.

A model for water discharge based on energy consumption data (WATEN).

NASA Astrophysics Data System (ADS)

Moyano, María Carmen; Tornos, Lucía; Juana, Luis

2014-05-01

As the need for water conservation is becoming a major water concern, a lumped model entitled WATEN has been proposed to analyse the water balance in the B-XII Irrigation Sector of the Lower Guadalquivir Irrigated Area, one of the largest irrigated areas in Spain. The aim of this work is to approach the hydrological study of an irrigation district lacking of robust data in such a manner that the water balance is performed from less to more process complexity. WATEN parameters are the total and readily available moisture in the soil, a fix percentage for effective precipitation, and the irrigation efficiency. The Sector presents six different drainage pumping stations, with particular pumping groups and with no water flow measurement devices. Energy consumption depends on the working pumping stations and groups, and on the variable water level to discharge. Energy consumed in the drainage pumping stations has been used for calibration The study has relied on two monthly series of data: the volume of drainage obtained from the model and the energy consumed in the pumping stations. A double mass analysis has permitted the detection of data tendencies. The two resulting series of data have been compared to assess model performance, particularly the Pearson's product moment correlation coefficient and the Nash-Sutcliffe coefficient of efficiency, e2, determined for monthly data and for annual and monthly average data. For model calibration, we have followed a classical approach based on objective functions optimization, and a robust approach based on Markov chain Monte Carlo simulation process, driven in a similar manner to genetic algorithms, entitled Parameters Estimation on Driven Trials (PEDT), and aiming to reduce computational requirements. WATEN has been parameterised maintaining its physical and conceptual rationality. The study approach is outlined as a progressive introduction of data. In this manner, we can observe its effect on the studied objective functions, and visualize if new data adds significant improvements to model results. The model attained an average Nash-Sutcliffe coefficient e2~= 0.90 between based on energy drainage observations and estimated drainage discharge. The study has shown that the Sector crop evapotranspiration, is lower than the expected value in pristine conditions. This reduction would be more noticeable at the end of the summer months, attaining as far as a 40% reduction. Average drainage in the studied period, is about 3700 m3/ha/year. This methodology is thought to be the basis for similar worldwide studies comprising scarce-data irrigation districts with drainage discharge to receiving water bodies, and serve as a guide for future alike applications.

Hydrologic connectivity: Quantitative assessments of hydrologic-enforced drainage structures in an elevation model

USGS Publications Warehouse

Poppenga, Sandra K.; Worstell, Bruce B.

2016-01-01

Elevation data derived from light detection and ranging present challenges for hydrologic modeling as the elevation surface includes bridge decks and elevated road features overlaying culvert drainage structures. In reality, water is carried through these structures; however, in the elevation surface these features impede modeled overland surface flow. Thus, a hydrologically-enforced elevation surface is needed for hydrodynamic modeling. In the Delaware River Basin, hydrologic-enforcement techniques were used to modify elevations to simulate how constructed drainage structures allow overland surface flow. By calculating residuals between unfilled and filled elevation surfaces, artificially pooled depressions that formed upstream of constructed drainage structure features were defined, and elevation values were adjusted by generating transects at the location of the drainage structures. An assessment of each hydrologically-enforced drainage structure was conducted using field-surveyed culvert and bridge coordinates obtained from numerous public agencies, but it was discovered the disparate drainage structure datasets were not comprehensive enough to assess all remotely located depressions in need of hydrologic-enforcement. Alternatively, orthoimagery was interpreted to define drainage structures near each depression, and these locations were used as reference points for a quantitative hydrologic-enforcement assessment. The orthoimagery-interpreted reference points resulted in a larger corresponding sample size than the assessment between hydrologic-enforced transects and field-surveyed data. This assessment demonstrates the viability of rules-based hydrologic-enforcement that is needed to achieve hydrologic connectivity, which is valuable for hydrodynamic models in sensitive coastal regions. Hydrologic-enforced elevation data are also essential for merging with topographic/bathymetric elevation data that extend over vulnerable urbanized areas and dynamic coastal regions.

Effect of chest physiotherapy on the removal of mucus in patients with cystic fibrosis

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

Rossman, C.M.; Waldes, R.; Sampson, D.

1982-07-01

We studied the effectiveness of some of the components of a physiotherapy regimen on the removal of mucus from the lungs of 6 subjects with cystic fibrosis. On 5 randomized study days, after inhalation of a /sup 99/mTc-human serum albumin aerosol to label primarily the large airways, the removal of lung radioactivity was measured during 40 min of (a) spontaneous cough while at rest (control), (b) postural drainage, (c) postural drainage plus mechanical percussion, (d) combined maneuvers (postural drainage, deep breathing with vibrations, and percussion) administered by a physiotherapist, (e) directed vigorous cough. Measurements continued for an additional 2 hmore » of quiet rest. Compared with the control day, all forms of intervention significantly improved the removal of mucus: cough (p less than 0.005), physiotherapy maneuvers (0.005 less than or equal to p less than 0.01), postural drainage (p less than 0.05), and postural drainage plus percussion (p less than 0.01). However, there was no significant difference between regimented cough alone and therapist-administered combined maneuvers, nor between postural drainage alone and with mechanical percussion. We conclude that in cystic fibrosis, vigorous, regimented cough sessions may be as effective as therapist-administered physiotherapy in removing pulmonary secretions. Postural drainage, although better than the control maneuver, was not as effective as cough and was not enhanced by mechanical percussion. Frequent, vigorous self-directed cough sessions are potentially as useful as more complex measures for effective bronchial toilet.« less

Detecting seasonal and cyclical trends in agricultural runoff water quality-hypothesis tests and block bootstrap power analysis.

PubMed

Uddameri, Venkatesh; Singaraju, Sreeram; Hernandez, E Annette

2018-02-21

Seasonal and cyclic trends in nutrient concentrations at four agricultural drainage ditches were assessed using a dataset generated from a multivariate, multiscale, multiyear water quality monitoring effort in the agriculturally dominant Lower Rio Grande Valley (LRGV) River Watershed in South Texas. An innovative bootstrap sampling-based power analysis procedure was developed to evaluate the ability of Mann-Whitney and Noether tests to discern trends and to guide future monitoring efforts. The Mann-Whitney U test was able to detect significant changes between summer and winter nutrient concentrations at sites with lower depths and unimpeded flows. Pollutant dilution, non-agricultural loadings, and in-channel flow structures (weirs) masked the effects of seasonality. The detection of cyclical trends using the Noether test was highest in the presence of vegetation mainly for total phosphorus and oxidized nitrogen (nitrite + nitrate) compared to dissolved phosphorus and reduced nitrogen (total Kjeldahl nitrogen-TKN). Prospective power analysis indicated that while increased monitoring can lead to higher statistical power, the effect size (i.e., the total number of trend sequences within a time-series) had a greater influence on the Noether test. Both Mann-Whitney and Noether tests provide complementary information on seasonal and cyclic behavior of pollutant concentrations and are affected by different processes. The results from these statistical tests when evaluated in the context of flow, vegetation, and in-channel hydraulic alterations can help guide future data collection and monitoring efforts. The study highlights the need for long-term monitoring of agricultural drainage ditches to properly discern seasonal and cyclical trends.

Abdominal drainage following cholecystectomy: high, low, or no suction?

PubMed Central

McCormack, T. T.; Abel, P. D.; Collins, C. D.

1983-01-01

A prospective trial to assess the effect of suction in an abdominal drain following cholecystectomy was carried out. Three types of closed drainage system were compared: a simple tube drain, a low negative pressure drain, and a high negative pressure drain: 120 consecutive patients undergoing cholecystectomy were randomly allocated to one of the three drainage groups. There was no significant difference in postoperative pyrexia, wound infection, chest infection, or hospital stay. This study failed to demonstrate any clinically useful difference between high negative pressure, low negative pressure, and static drainage system were compared: a simple tube drain, a low negative used, suction is not necessary and a simple tube drain (greater than 6 mm internal diameter) is the most effective form of drainage. PMID:6614773

An analytical solution for predicting the transient seepage from a subsurface drainage system

NASA Astrophysics Data System (ADS)

Xin, Pei; Dan, Han-Cheng; Zhou, Tingzhang; Lu, Chunhui; Kong, Jun; Li, Ling

2016-05-01

Subsurface drainage systems have been widely used to deal with soil salinization and waterlogging problems around the world. In this paper, a mathematical model was introduced to quantify the transient behavior of the groundwater table and the seepage from a subsurface drainage system. Based on the assumption of a hydrostatic pressure distribution, the model considered the pore-water flow in both the phreatic and vadose soil zones. An approximate analytical solution for the model was derived to quantify the drainage of soils which were initially water-saturated. The analytical solution was validated against laboratory experiments and a 2-D Richards equation-based model, and found to predict well the transient water seepage from the subsurface drainage system. A saturated flow-based model was also tested and found to over-predict the time required for drainage and the total water seepage by nearly one order of magnitude, in comparison with the experimental results and the present analytical solution. During drainage, a vadose zone with a significant water storage capacity developed above the phreatic surface. A considerable amount of water still remained in the vadose zone at the steady state with the water table situated at the drain bottom. Sensitivity analyses demonstrated that effects of the vadose zone were intensified with an increased thickness of capillary fringe, capillary rise and/or burying depth of drains, in terms of the required drainage time and total water seepage. The analytical solution provides guidance for assessing the capillary effects on the effectiveness and efficiency of subsurface drainage systems for combating soil salinization and waterlogging problems.

The use of quilting suture in abdominoplasty does not require aspiratory drainage for prevention of seroma.

PubMed

Arantes, Henrique Lopes; Rosique, Rodrigo Gouvêa; Rosique, Marina Junqueira Ferreira; Mélega, Jose Marcos

2010-02-01

The formation of seromas after abdominoplasty is a highly prevalent complication that disturbs both the patient and the surgeon. Aspiratory drainage and adhesion sutures (Baroudi suture) are widely used to prevent this complication. This study evaluated the effectiveness of drains in preventing seromas. This retrospective study investigated women submitted to classic abdominoplasty with adhesion sutures. The women were divided into two groups. Group 1 comprised 28 individuals who received no drains, and group 2 consisted of 32 patients that had drains placed. Clinical evaluation of the patients was performed 7 days, 14 days, 1 month, 2 months, 4 months, and 6 months postoperatively. Statistical analysis was accomplished via Fisher's exact test. Group 1 had one case of seroma (3.5%), clinically detected between the first and second postoperative months, whereas group 2 had one case (3.12%) detected 14 days postoperatively. Fisher's test showed a P value of 1.000 (not statistically significant), for a 95% confidence interval of 0.05 to 14.08 and an odds ratio of 0.8387. Clinical evaluation showed no statistical difference in the incidence of seromas after abdominoplasty with adhesion sutures between the patients who received drains and those who did not. The use of adhesion sutures is an effective measure for preventing seromas with no need for additional surgical measures.

Potential for Remotely Sensed Soil Moisture Data in Hydrologic Modeling

NASA Technical Reports Server (NTRS)

Engman, Edwin T.

1997-01-01

Many hydrologic processes display a unique signature that is detectable with microwave remote sensing. These signatures are in the form of the spatial and temporal distributions of surface soil moisture and portray the spatial heterogeneity of hydrologic processes and properties that one encounters in drainage basins. The hydrologic processes that may be detected include ground water recharge and discharge zones, storm runoff contributing areas, regions of potential and less than potential ET, and information about the hydrologic properties of soils and heterogeneity of hydrologic parameters. Microwave remote sensing has the potential to detect these signatures within a basin in the form of volumetric soil moisture measurements in the top few cm. These signatures should provide information on how and where to apply soil physical parameters in distributed and lumped parameter models and how to subdivide drainage basins into hydrologically similar sub-basins.

Characterization of stormwater discharges from Las Flores Industrial Park, Rio Grande, Puerto Rico, 1998-99

USGS Publications Warehouse

Rodriguez, Jose M.

2000-01-01

Stormwater discharges from Las Flores Industrial Park, Rio Grande, Puerto Rico, were characterized from June 1998 to July 1999 by measuring the flow rate at two outfalls, delineating the drainage areas for each outfall, and calculating the volume of the stormwater discharges. Stormwater-discharge samples were collected and analyzed to determine the quality of the discharges. Constituent loads and loads per area were estimated for each drainage area. The studied drainage subareas covered approximately 46 percent of the total area of the Las Flores Industrial Park. Industrial groups represented in the study areas include manufacturers of textile, electronics, paper, fabricated metal, plastic, and chemical products. The concentrations of oil and grease (1 to 6 milligrams per liter), biochemical oxygen demand (4.7 to 16 milligrams per liter), total organic carbon (5.8 to 36 milligrams per liter), total suspended solids (28 to 100 milligrams per liter), and total phosphorous (0.11 to 0.78 milligrams per liter) from all the samples collected were less than the U.S. Environmental Protection Agency stormwater benchmark concentrations. Concentrations of chemical oxygen demand (15.8 to 157 milligrams per liter) and nitrate and nitrite (0.06 to 1.75 milligrams per liter) exceeded benchmark concentrations at one of the studied drainage areas. Total Kjeldahl nitrogen concentrations (1.00 to 3.20 milligrams per liter) exceeded the benchmark concentrations at the two studied drainage areas. Maximum concentrations for oil and grease, biochemical oxygen demand, chemical oxygen demand, total organic carbon, total Kjeldahl nitrogen, nitrate plus nitrite, and total phosphorous were detected in an area where electronics, plastics, and chemical products are currently manufactured. The maximum concentration of total suspended solids was detected at an area where textile, paper, plastic, chemical, and fabricated metal products are manufactured.

Land drainage system detection using IR and visual imagery taken from autonomous mapping airship and evaluation of physical and spatial parameters of suggested method

NASA Astrophysics Data System (ADS)

Koska, Bronislav; Křemen, Tomáš; Štroner, Martin; Pospíšil, Jiří; Jirka, Vladimír.

2014-10-01

An experimental approach to the land drainage system detection and its physical and spatial parameters evaluation by the form of pilot project is presented in this paper. The novelty of the approach is partly based on using of unique unmanned aerial vehicle - airship with some specific properties. The most important parameters are carrying capacity (15 kg) and long flight time (3 hours). A special instrumentation was installed for physical characteristic testing in the locality too. The most important is 30 meter high mast with 3 meter length bracket at the top with sensors recording absolute and comparative temperature, humidity and wind speed and direction in several heights of the mast. There were also installed several measuring units recording local condition in the area. Recorded data were compared with IR images taken from airship platform. The locality is situated around village Domanín in the Czech Republic and has size about 1.8 x 1.5 km. There was build a land drainage system during the 70-ties of the last century which is made from burnt ceramic blocks placed about 70 cm below surface. The project documentation of the land drainage system exists but real state surveying haveńt been never realized. The aim of the project was land surveying of land drainage system based on infrared, visual and its combination high resolution orthophotos (10 cm for VIS and 30 cm for IR) and spatial and physical parameters evaluation of the presented procedure. The orthophoto in VIS and IR spectrum and its combination seems to be suitable for the task.

An Optimal Balance between Efficiency and Safety of Urban Drainage Networks

NASA Astrophysics Data System (ADS)

Seo, Y.

2014-12-01

Urban drainage networks have been developed to promote the efficiency of a system in terms of drainage time so far. Typically, a drainage system is designed to drain water from developed areas promptly as much as possible during floods. In this regard, an artificial drainage system have been considered to be more efficient compared to river networks in nature. This study examined artificial drainage networks and the results indicate they can be less efficient in terms of network configuration compared with river networks, which is counter-intuitive. The case study of 20 catchments in Seoul, South Korea shows that they have wide range of efficiency in terms of network configuration and consequently, drainage time. This study also demonstrates that efficient drainage networks are more sensitive to spatial and temporal rainfall variation such as rainstorm movement. Peak flows increase more than two times greater in effective drainage networks compared with inefficient and highly sinuous drainage networks. Combining these results, this study implies that the layout of a drainage network is an important factor in terms of efficient drainage and also safety in urban catchments. Design of an optimal layout of the drainage network can be an alternative non-structural measures that mitigate potential risks and it is crucial for the sustainability of urban environments.

Effects of hillslope gully stabilization on erosion and sediment production in the Torreon Wash watershed, New Mexico, 2009–12

USGS Publications Warehouse

Matherne, Anne Marie; Tillery, Anne C.; Douglas-Mankin, Kyle R.

2018-04-10

Sediment erosion and deposition in two sets of paired (treated and untreated) upland drainages in the Torreon Wash watershed, upper Rio Puerco Basin, New Mexico, were examined over a 3 1/2-year period from spring 2009 through fall 2012. The objective was to evaluate the effectiveness of shallow, loose-stone check dams, or “one-rock dams,” as a hillslope gully erosion stabilization and mitigation method, and its potential for retaining upland eroded soils and decreasing delivery of sediment to lower ephemeral stream channels. Two high-resolution topographic surveys, completed at the beginning and end of the study period, were used to assess the effects of the mitigation measures at paired-drainage sites in both Penistaja Arroyo and Papers Wash watersheds, and at six main-stem-channel cross-section clusters along Penistaja Arroyo and Torreon Wash in the Torreon Wash watershed.For both drainage pairs, the treated drainage had greater sediment aggradation near the channel than the untreated drainage. Erosion was the dominant geomorphic process in the untreated Penistaja Arroyo drainage, whereas aggradation was the dominant process in the other three drainages. For the Penistaja Arroyo paired drainages, the treated site showed a 51-percent increase in area aggraded and 67-percent increase in volume aggraded per area analyzed over the untreated site. Both Papers Wash drainages showed net aggradation, but with similar treatment effect, with the treated site showing a 29-percent increase in area aggraded and 60-percent increase in volume aggraded per area analyzed over the untreated site. In the untreated Penistaja Arroyo drainage, the calculated minimum erosion rate was 0.0055 inches per year (in/yr; 0.14 millimeters per year [mm/yr]), whereas the calculated aggradation rates for the three drainages for which aggradation was the dominant geomorphic process were 0.0063 in/yr (0.16 mm/yr) for the Penistaja Arroyo treated drainage, 0.012 in/yr (0.31 mm/yr) for the Papers Wash untreated drainage, and 0.988 in/yr (2.51 mm/yr) for the Papers Wash treated drainage.Changes in the channel cross section along the main-stem Penistaja Arroyo and Torreon Wash were also examined. Channel-bank slumping and erosion of previously deposited bed material were apparent sources for sediment suspended in ephemeral streamflow. Cross-sectional channel surveys indicated examples of both erosion and deposition along each channel over the study period. Because the drainage area of the treated drainages is small compared to that of the Torreon Wash watershed, the upland mitigation measures would not be expected to measurably affect short-term concentrations of suspended sediment in main-stem channels.One-rock-dam mitigation structures in the upland drainages appear to have resulted in a decrease in sediment delivery to the main-stem channel. One-rock-dam mitigation structures may affect streamflow through their influence on runoff volume (via infiltration) and runoff rate (via detention), both of which may vary with time after structure installation.

Regulation of drainage canals on the groundwater level in a typical coastal wetlands

NASA Astrophysics Data System (ADS)

Liu, Qiang; Mou, Xia; Cui, Baoshan; Ping, Fan

2017-12-01

Activities related to reclamation alter wetland hydrological regimes and inevitably cause changes to groundwater level, which can result in the ecological degradation of coastal wetlands. Decreasing the groundwater level by the construction of drainage canals is an approach that has been widely used to control levels of root zone soil salinity as well as to protect freshwater wetlands or to expand agricultural land area in coastal wetlands. In this study, we assessed the influences of different drainage canal designs on the groundwater level using the Visual MODFLOW (VMOD) interface. We also provided an optimized drainage canal design suitable for the Yellow River Delta (YRD). Results showed that: (i) the groundwater level decreased in areas close to drainage canals, while only negligible effects were found on the groundwater level in areas with no drainage canals; (ii) the influence of drainage canals on the groundwater level decreased as distance increased; and (iii) a drainage canal network design of a depth of 5 m, with canal configuration of north-south direction and canal spacing of 1000 m was more effective in reducing the groundwater level in the study area. Our findings indicated that changes in groundwater level by the construction of drainage canals could help in our understanding of how groundwater influences freshwater wetlands and also aid in maintaining the integrity of coastal wetlands.

Vaccum drainage system application in the management of operation-related non-regional epidural hematoma

PubMed Central

2013-01-01

Background Epidural intracranial hematoma is one of the most common complications of surgeries for intracranial tumors. The non-regional epidural hematoma is related to severe fluctuation of the intracranial pressure during the operation. The traditional management of hematoma evacuation through craniotomy is time-consuming and may aggravate intracranial pressure imbalance, which causes further complications. We designed a method using vaccum epidural drainage system, and tried to evaluate advantage and the disadvantage of this new technique. Methods Seven patients of intracranial tumors were selected. All of the patients received tumor resection and intra-operative non-regional epidural hematoma was confirmed through intra-operative ultrasound or CT scan. The vaccum drainage system was applied. Another ten patients who received craniotomy for intra-operative non-regional epidural hematoma evacuation were selected as comparison. Regular tests, like serial CT scan, were performed afterward to evaluate the effectiveness and to help deciding when to remove the drainage system. Results The vaccum drainage method was effective in epidual hemotoma clearance and prevented recurrent epidural hemorrhage. The drainage systems were removed within 4 days. All of the patients recovered well. No complications related to the drainage system were observed. Conclusions Compared to the traditional craniotomy, the new method of epidural hemoatoma management using vaccum epidural drainage system proved to be as effective in hematoma clearance, and was less-invasive and easier to perform, with less complication, shorter hospitalization, less economic burden, and better prognosis. PMID:23842198

Co-development of climate smart flooded rice farming systems

NASA Astrophysics Data System (ADS)

de Neergaard, Andreas; Stoumann Jensen, Lars; Ly, Proyuth; Pandey, Arjun; Duong Vu, Quynh; Tariq, Azeem; Islam, Syed; van Groenigen, Jan Willem; Sander, Bjoern Ole; de Tourdonnet, Stephane; Van Mai, Trinh; Wassmann, Reiner

2017-04-01

Mid-season drainage in flooded rice is known to reduce CH4 emission, while effects on N2O emission are more variable. Banning of crop-residue burning, and growing markets for organically fertilized rice, are resulting in systems with larger reactive C input, and potentially larger methane emissions. Tight farming systems with 2 or 3 annual crops are effective in mitigating emissions, in that the land sparing value is high, but put serious constraints on mitigation options under increased C input scenarios. In a series of field (Cambodia, Philippines and Vietnam) and greenhouse experiments, we investigated the effect of a variety of organic amendments and wetting and drying cycles on yield and GHG emissions. Specifically we have tested the effect of inserting very early, or even-pre-planting drainage, as a means to accelerate turnover of straw or other C sources, and reduce methane emission later in the season. Overall, our results showed that drying periods had minimal impact on yields, while reducing overall GHG emission. Methane emission was strongly controlled by C availability in the substrate (on equal total C-input basis), increasing in the order: biochar-composts-animal manure-fresh material. Nitrous oxide emissions generally increased with draining cycles, but did not lead to overall increase in GHG emissions as its contribution was balanced by lowered CH4 emissions. Growth chamber experiments showed that methane emission was significantly reduced for extended periods after re-flooding, hence the idea of early drainage was developed. Meanwhile, Cambodian farmers expressed concerns over re-supply of water after drainage. In response to that, we tested if early-season drainage could replace mid-season drainage. With addition of labile carbon substrates (straw) duration of early season drainage was more important for reducing GHG emissions, than duration of mid-season drainage, and had the highest potential for total emission reduction. In a farmers-field trial in Vietnam, pre-planting and early season drainage was tested in spring and summer rice, under individual and community water management regimes, and at 2 straw application levels. Pre-season drainage was difficult for farmers to implement, due to the short duration of fallow between cropping seasons. Early season drainage was most effective in lowering methane emissions at both straw application levels. Unsurprisingly, the well-managed drainage control (community system) was significantly more effective in mitigating emissions, than the individually water management. Surveys among farming communities in Philippines, subject to agricultural campaigns on alternate-wetting-and-drying showed higher adoption among farmers who actively pumped water to their fields, compared to gravity-fed water supply, due to the direct savings experienced by farmers pumping water. Several other factors positively influenced adoption of mitigation techniques, including education level, access to extension services, wealth and farm size, and age of farmer (negatively correlated to adoption rate). In conclusion, drainage periods are even more important to mitigate emissions when including organic manures or residues in flooded rice, and early-season drainage should be further explored as a more safe and convenient option for smallholders. Participatory development of climate smart prototypes will be essential, and a model for such is presented.

Drainage water management

USDA-ARS?s Scientific Manuscript database

This article introduces a series of papers that report results of field studies to determine the effectiveness of drainage water management (DWM) on conserving drainage water and reducing losses of nitrogen (N) to surface waters. The series is focused on the performance of the DWM (also called contr...

Randomised clinical trial of chest drainage systems.

PubMed Central

Graham, A N; Cosgrove, A P; Gibbons, J R; McGuigan, J A

1992-01-01

BACKGROUND: Problems in the management of thoracic trauma have stimulated the search for an alternative to underwater seals for drainage of the pleural cavity. A chest drainage bag incorporating a one way flutter valve has been compared with underwater seal drains in a randomised clinical trial. METHODS: During June-December 1989 119 patients undergoing elective thoracotomy were randomised to receive postoperative chest drainage by drainage bags (56 patients, 87 drains) or by underwater seal drains (63 patients, 98 drains). Daily drainage volumes, the requirement for pleural suction, mobility, and complications were recorded prospectively. RESULTS: There was no significant difference between the two groups in the mean volume drained, the requirements for pleural suction, or the occurrence of complications. Patients with drainage bags were fully mobile 23 hours (95% confidence interval 0-47 hours) earlier than the others. CONCLUSIONS: When used after elective thoracotomy drainage bags are safe and effective and permit earlier mobility than underwater seal drains. PMID:1496507

Areas of localized organochlorine contamination in Arizona and New Mexico

USGS Publications Warehouse

Fleming, W.J.; Cain, B.W.

1985-01-01

Wings from mallard ducks harvested in 1980 in Arizona, Arkansas, Louisiana, and New Mexico were pooled into county aggregates and analyzed for organochlorine pesticides and PCB's. Organochlorine concentrations in duck wings were compared among counties comprising major river drainages within each state. DDE concentrations in the wings of mallards collected from the Verde River and the lower portion of the Gila River drainages in Arizona ranged up to 6 ppm (wet weight basis), which was 17 times higher than the 1979 Pacific Flyway average. DDE at these high levels may be hazardous to wildlife. In combination with other published data, our findings indicate a serious DDT problem in portions of the Verde River and Gila River drainages. High levels of heptachlor (up to 1.7 ppm) and PCB's (3.7 ppm, 61 times the 1979 Central Flyway average) were found in mallard wings from the upper Rio Grande and Pecos River drainages, respectively. We did not detect areas of heavy local organochlorine pesticide or PCB contamination in Arkansas and Louisiana.

Comparison of endoscopic and percutaneous drainage of symptomatic necrotic collections in acute necrotizing pancreatitis.

PubMed

Woo, Shanan; Walklin, Ryan; Ackermann, Travis; Lo, Sheng Wei; Shilton, Hamish; Pilgrim, Charles; Evans, Peter; Burnes, James; Croagh, Daniel

2018-05-10

Primary endoscopic and percutaneous drainage for pancreatic necrotic collections is increasingly used. We aim to compare the relative effectiveness of both modalities in reducing the duration and severity of illness by measuring their effects on systemic inflammatory response syndrome (SIRS). We retrospectively reviewed all cases of endoscopic and percutaneous drainage for pancreatic necrotic collections performed in 2011-2016 at two hospitals. We assessed the post-procedure length of hospital stay, reduction in C-reactive protein levels, resolution of SIRS, the complication rates, and the number of procedures required for resolution. Thirty-two patients were identified and 57 cases (36 endoscopic, 21 percutaneous) were included. There was no significant difference in C-reactive protein reduction between endoscopic and percutaneous drainage (69.5% vs 68.8%, P = 0.224). Resolution of SIRS was defined as the post-procedure normalization of white cell count (endoscopic vs percutaneous: 70.4% vs 64.3%, P = 0.477), temperature (endoscopic vs percutaneous: 93.3% vs 60.0%, P = 0.064), heart rate (endoscopic vs percutaneous: 56.0% vs 11.1%, P = 0.0234), and respiratory rate (endoscopic vs percutaneous: 83.3% vs 0.0%, P = 0.00339). Post-procedure length of hospital stay was 27 days with endoscopic drainage and 46 days with percutaneous drainage (P = 0.0183). Endoscopic drainage was associated with a shorter post-procedure length of hospital stay and a greater rate of normalization of SIRS parameters than percutaneous drainage, although only the effects on heart rate and respiratory rate reached statistical significance. Further studies are needed to establish which primary drainage modality is superior for pancreatic necrotic collections. © 2018 Japan Society for Endoscopic Surgery, Asia Endosurgery Task Force and John Wiley & Sons Australia, Ltd.

Systematic review and meta-analysis of prophylactic abdominal drainage after pancreatic resection

PubMed Central

Dou, Chang-Wei; Liu, Zhi-Kui; Jia, Yu-Li; Zheng, Xin; Tu, Kang-Sheng; Yao, Ying-Min; Liu, Qing-Guang

2015-01-01

AIM: To investigate whether prophylactic abdominal drainage is necessary after pancreatic resection. METHODS: PubMed, Web of Science, and the Cochrane Library were systematically searched to obtain relevant articles published before January 2014. Publications were retrieved if they met the selection criteria. The outcomes of interest included: mortality, morbidity, postoperative pancreatic fistula (POPF), clinically relevant pancreatic fistula (CR-PF), abdominal abscess, reoperation rate, the rate of interventional radiology drainage, and the length of hospital stay. Subgroup analyses were also performed for pancreaticoduodenectomy (PD) and for distal pancreatectomy. Begg’s funnel plot and the Egger regression test were employed to assess potential publication bias. RESULTS: Nine eligible studies involving a total of 2794 patients were identified and included in this meta-analysis. Of the included patients, 1373 received prophylactic abdominal drainage. A fixed-effects model meta-analysis showed that placement of prophylactic drainage did not have beneficial effects on clinical outcomes, including morbidity, POPF, CR-PF, reoperation, interventional radiology drainage, and length of hospital stay (Ps > 0.05). In addition, prophylactic drainage did not significantly increase the risk of abdominal abscess. Overall analysis showed that omitting prophylactic abdominal drainage resulted in higher mortality after pancreatectomy (OR = 1.56; 95%CI: 0.93-2.92). Subgroup analysis of PD showed similar results to those in the overall analysis. Elimination of prophylactic abdominal drainage after PD led to a significant increase in mortality (OR = 2.39; 95%CI: 1.22-4.69; P = 0.01). CONCLUSION: Prophylactic abdominal drainage after pancreatic resection is still necessary, though more evidence from randomized controlled trials assessing prophylactic drainage after PD and distal pancreatectomy are needed. PMID:25987799

Digital simulation of the effects of urbanization on runoff in the upper Santa Ana Valley, California

USGS Publications Warehouse

Durbin, Timothy J.

1974-01-01

The Stanford Watershed Model was used to simulate the effects of urbanization on the discharge from five drainage basins in the upper Santa Ana Valley, an area with an average annual precipitation of 15 inches. The drainage basins ranged in size from 3.72 to 83.4 square miles. Using the model, synthetic records of streamflow for each basin were generated to represent various degrees of urban development. Examination of the synthetic records indicated that urbanization has the following effects on streamflow in the area:Average annual runoff from a drainage basin with an effective impervious area of 10 percent of the drainage area is approximately 2 inches, and increases by 1 inch for each increase in effective impervious cover equal to 10 percent of the drainage area. About 30 percent of a fully urbanized area is effectively impervious.Urbanization can increase the magnitude of peak discharge and daily mean discharge with a recurrence interval of 2 years by a factor of three to six.Peak discharges and daily mean discharges that have recurrence intervals greater than a limiting value ranging from 50 to 200 years or more are little affected by urbanization.

Glacial lake drainage in Patagonia (13-8 kyr) and response of the adjacent Pacific Ocean

PubMed Central

Glasser, Neil F.; Jansson, Krister N.; Duller, Geoffrey A. T.; Singarayer, Joy; Holloway, Max; Harrison, Stephan

2016-01-01

Large freshwater lakes formed in North America and Europe during deglaciation following the Last Glacial Maximum. Rapid drainage of these lakes into the Oceans resulted in abrupt perturbations in climate, including the Younger Dryas and 8.2 kyr cooling events. In the mid-latitudes of the Southern Hemisphere major glacial lakes also formed and drained during deglaciation but little is known about the magnitude, organization and timing of these drainage events and their effect on regional climate. We use 16 new single-grain optically stimulated luminescence (OSL) dates to define three stages of rapid glacial lake drainage in the Lago General Carrera/Lago Buenos Aires and Lago Cohrane/Pueyrredón basins of Patagonia and provide the first assessment of the effects of lake drainage on the Pacific Ocean. Lake drainage occurred between 13 and 8 kyr ago and was initially gradual eastward into the Atlantic, then subsequently reorganized westward into the Pacific as new drainage routes opened up during Patagonian Ice Sheet deglaciation. Coupled ocean-atmosphere model experiments using HadCM3 with an imposed freshwater surface “hosing” to simulate glacial lake drainage suggest that a negative salinity anomaly was advected south around Cape Horn, resulting in brief but significant impacts on coastal ocean vertical mixing and regional climate. PMID:26869235

Burr-hole Irrigation with Closed-system Drainage for the Treatment of Chronic Subdural Hematoma: A Meta-analysis

PubMed Central

XU, Chen; CHEN, Shiwen; YUAN, Lutao; JING, Yao

2016-01-01

There is controversy among neurosurgeons regarding whether irrigation or drainage is necessary for achieving a lower revision rate for the treatment of chronic subdural hematoma (CSDH) using burr-hole craniostomy (BHC). Therefore, we performed a meta-analysis of all available published reports. Multiple electronic health databases were searched to identify all studies published between 1989 and June 2012 that compared irrigation and drainage. Data were processed by using Review Manager 5.1.6. Effect sizes are expressed as pooled odds ratio (OR) estimates. Due to heterogeneity between studies, we used the random effect of the inverse variance weighted method to perform the meta-analysis. Thirteen published reports were selected for this meta-analysis. The comprehensive results indicated that there were no statistically significant differences in mortality or complication rates between drainage and no drainage (P > 0.05). Additionally, there were no differences in recurrence between irrigation and no irrigation (P > 0.05). However, the difference between drainage and no drainage in recurrence rate reached statistical significance (P < 0.01). The results from this meta-analysis suggest that burr-hole surgery with closed-system drainage can reduce the recurrence of CSDH; however, irrigation is not necessary for every patient. PMID:26377830

Drainage isolation and climate change-driven population expansion shape the genetic structures of Tuber indicum complex in the Hengduan Mountains region.

PubMed

Feng, Bang; Zhao, Qi; Xu, Jianping; Qin, Jiao; Yang, Zhu L

2016-02-24

The orogenesis of the Qinghai-Tibetan Plateau and the Quaternary climate changes have played key roles in driving the evolution of flora and fauna in Southwest China, but their effects on higher fungi are poorly addressed. In this study, we investigated the phylogeographic pattern of the Tuber indicum species complex, an economically important fungal group distributed in the Hengduan Mountains region. Our data confirmed the existence of two distinct lineages, T. indicum and T. himalayense, within this species complex. Three geographic groups (Groups W, N and C) were revealed within T. indicum, with Group W found in the paleo-Lancang River region, while Groups N and C corresponded to the two banks along the contemporary Jinsha River, suggesting that rivers have acted as barriers for gene flow among populations from different drainages. Historical range expansion resulted from climate changes was inferred in Group C, contributing to the observed gene flow among geographic populations within this group. Although no significant geographic structure was identified in T. himalayense, evidence of drainage isolation for this species was also detected. Our findings demonstrate that both topographic changes and Quaternary climate oscillations have played important roles in driving the genetic structures of the T. indicum species complex.

Effects of blockade of cerebral lymphatic drainage on regional cerebral blood flow and brain edema after subarachnoid hemorrhage.

PubMed

Sun, Bao-Liang; Xia, Zuo-Li; Wang, Jing-Ru; Yuan, Hui; Li, Wen-Xia; Chen, Yu-She; Yang, Ming-Feng; Zhang, Su-Ming

2006-01-01

The study was designed to observe the influence of blockade of cerebral lymphatic drainage on the regional cerebral blood flow (rCBF) and brain edema after experimental subarachnoid hemorrhage (SAH). Wistar rats were divided into non-SAH, SAH, and SAH plus cervical lymphatic blockade (SAH + CLB) groups. Autologous arterial hemolysate was injected into rat's cisterna magna to induce SAH. The rCBF was recorded continuously by a laser Doppler flowmeter. Intracranial pressure (ICP) was also monitored. After 24 hours and 72 hours of SAH, the rats were sacrificed and the brain was harvested for water content detection. It was found that there was no obvious change of rCBF and brain water content during the experiment in non-SAH group. An immediate and persistent drop in rCBF was found in SAH group. The drop in rCBF was more obvious in SAH + CLB group. CLB also worsened the SAH-induced increase in ICP. The brain water content 24 hours and 72 hours after induction of SAH in SAH group increased significantly. CLB led to a further increase of brain water content. In conclusion, blockade of cerebral lymphatic drainage pathway deteriorates the secondary cerebral ischemia and brain edema after SAH.

Tropospheric ozone in the Nisqually River Drainage, Mount Rainier National Park

USGS Publications Warehouse

Peterson, D.L.; Bowers, Darci

1999-01-01

We quantified the summertime distribution of tropospheric ozone in the topographically complex Nisqually River drainage of Mount Rainier National Park from 1994 to 1997. Passive ozone samplers were used along an elevational transect to measure weekly average ozone concentrations ranging from 570 m to 2040 m elevation. Weekly average ozone concentrations were positively correlated with elevation, with the highest concentrations consistently measured at the highest sampling site (Panorama Point). Weekly average ozone concentrations at Mount Rainier National Park are considerably higher than those in the Seattle-Tacoma metropolitan area to the west. The anthropogenic contribution to ozone within the Nisqually drainage was evaluated by comparing measurements at this location with measurements from a 'reference' site in the western Olympic Mountains. The comparison suggests there is a significant anthropogenic source of ozone reaching the Cascade Range via atmospheric transport from urban areas to the west. In addition. temporal (week to week) variation in ozone distribution is synchronous within the Nisqually drainage, which indicates that subregional patterns are detectable with weekly averages. The Nisqually drainage is likely the 'hot spot' for air pollution in Mount Rainier National Park. By using passive ozone samplers in this drainage in conjunction with a limited number of continuous analyzers, the park will have a robust monitoring approach for measuring tropospheric ozone over time and protecting vegetative and human health.

Transcutaneous Drainage of Gel-Like Substance after Application of Hydrogel Dural Sealant: Report of Two Cases.

PubMed

Siman, Homayoun; Techy, Fernando

2016-02-01

Study Design Case report. Objective Incidental durotomy (IDT) is a common complication of spinal surgery. The use of collagen matrix graft along with hydrogel dural sealant is a common method of IDT repair. With this method, there have been several reported cases of detrimental dural sealant expansion in the literature. One case study reported an expansion rate greater than 300%; many report neurologic damage. This article reports the clinical course of two patients who developed postoperative transcutaneous drainage of a gel-like substance after the use of a dural sealant, which is a previously unreported complication. Methods The clinical course and treatment outcome of two patients is presented. Results Both patients experienced postoperative transcutaneous drainage of a gel-like substance at the surgical site. Case one began draining this substance on postoperative day 14. This patient required no further intervention, and the drainage ended after 3 mL of a gel-like substance was expressed from his incision while in the clinic. Case two began draining the gel on postoperative day 16. This patient underwent two washout procedures and resolution of the drainage. No infection was ever detected. Conclusions To our knowledge, our patients are the first reported cases of transcutaneous drainage of expanded dural sealant. It is important to take into consideration the unexpected expansion of a dural sealant when using it for the repair of IDT.

Transcutaneous Drainage of Gel-Like Substance after Application of Hydrogel Dural Sealant: Report of Two Cases

PubMed Central

Siman, Homayoun; Techy, Fernando

2015-01-01

Study Design Case report. Objective Incidental durotomy (IDT) is a common complication of spinal surgery. The use of collagen matrix graft along with hydrogel dural sealant is a common method of IDT repair. With this method, there have been several reported cases of detrimental dural sealant expansion in the literature. One case study reported an expansion rate greater than 300%; many report neurologic damage. This article reports the clinical course of two patients who developed postoperative transcutaneous drainage of a gel-like substance after the use of a dural sealant, which is a previously unreported complication. Methods The clinical course and treatment outcome of two patients is presented. Results Both patients experienced postoperative transcutaneous drainage of a gel-like substance at the surgical site. Case one began draining this substance on postoperative day 14. This patient required no further intervention, and the drainage ended after 3 mL of a gel-like substance was expressed from his incision while in the clinic. Case two began draining the gel on postoperative day 16. This patient underwent two washout procedures and resolution of the drainage. No infection was ever detected. Conclusions To our knowledge, our patients are the first reported cases of transcutaneous drainage of expanded dural sealant. It is important to take into consideration the unexpected expansion of a dural sealant when using it for the repair of IDT. PMID:26835216

Eosinophilic plasmacytic conjunctivitis concurrent with gingival fistula caused by Schizophyllum commune in a captive cheetah (Acinonyx jubatus).

PubMed

Yoshizawa, Madoka; Kawarai, Shinpei; Torii, Yoshiko; Ota, Kaori; Tasaka, Kiyoshi; Nishimura, Kazuko; Fujii, Chieko; Kanemaki, Nobuyuki

2017-12-01

We describe for the first time the diagnosis of Schizophyllum commune infection in a captive cheetah. Eosinophilic plasmacytic conjunctivitis was detected histopathologically in a biopsy specimen. Both a second surgical specimen and drainage fluid from a gingival mass and fistula contained fungal hyphae in giant cells with granulomatous inflammation. Allergic S. commune mycosis was suspected at this point. A monokaryotic isolate was characterized morphologically, and then identified genetically. Treatment with itraconazole and pimaricin was effective.

Subglacial drainage patterns of Devon Island, Canada: detailed comparison of rivers and subglacial meltwater channels

NASA Astrophysics Data System (ADS)

Grau Galofre, Anna; Jellinek, A. Mark; Osinski, Gordon R.; Zanetti, Michael; Kukko, Antero

2018-04-01

Subglacial meltwater channels (N-channels) are attributed to erosion by meltwater in subglacial conduits. They exert a major control on meltwater accumulation at the base of ice sheets, serving as drainage pathways and modifying ice flow rates. The study of exposed relict subglacial channels offers a unique opportunity to characterize the geomorphologic fingerprint of subglacial erosion as well as study the structure and characteristics of ice sheet drainage systems. In this study we present detailed field and remote sensing observations of exposed subglacial meltwater channels in excellent preservation state on Devon Island (Canadian Arctic Archipelago). We characterize channel cross section, longitudinal profiles, and network morphologies and establish the spatial extent and distinctive characteristics of subglacial drainage systems. We use field-based GPS measurements of subglacial channel longitudinal profiles, along with stereo imagery-derived digital surface models (DSMs), and novel kinematic portable lidar data to establish a detailed characterization of subglacial channels in our field study area, including their distinction from rivers and other meltwater drainage systems. Subglacial channels typically cluster in groups of ˜ 10 channels and are oriented perpendicular to active or former ice margins. Although their overall direction generally follows topographic gradients, channels can be oblique to topographic gradients and have undulating longitudinal profiles. We also observe that the width of first-order tributaries is 1 to 2 orders of magnitude larger than in Devon Island river systems and approximately constant. Furthermore, our findings are consistent with theoretical expectations drawn from analyses of flow driven by gradients in effective water pressure related to variations in ice thickness. Our field and remote sensing observations represent the first high-resolution study of the subglacial geomorphology of the high Arctic, and provide quantitative and qualitative descriptions of subglacial channels that revisit well-established field identification guidelines. Distinguishing subglacial channels in topographic data is critical for understanding the emergence, geometry, and extent of channelized meltwater systems and their role in ice sheet drainage. The final aim of this study is to facilitate the identification of subglacial channel networks throughout the globe by using remote sensing techniques, which will improve the detection of these systems and help to build understanding of the underlying mechanics of subglacial channelized drainage.

Record of drainage rearrangement and erosion in a transpressive orogen: relative role of horizontal and vertical rock advection in drainage evolution

NASA Astrophysics Data System (ADS)

Brocard, G. Y.; Teyssier, C.; Dunlap, W. J.; Willenbring, J.; Simon-Labric, T.; Authemayou, C.

2008-12-01

Along transpressive orogens, both range-transverse and range-parallel motions influence drainage network evolution. Range-parallel motions promote stretching of drainage networks, river lengthening or shortening, and sudden shortenings by river capture. Range-transverse motions induce river course shortening or lengthening, and generates stronger rock uplift. River incision patterns are influenced by rock uplift and waves of incision resulting from drainage rearrangement. Thus, under steady conditions of wrenching, drainages evolve by continued deformation and discrete rearrangements. Therefore, a significant part of erosion can be achieved in a state of significant departure from dynamic equilibrium. The frequency, intensity, and duration of these events set the timescale over which their integrated effects can be regarded as the expression of a long-term dynamic equilibrium. We document the growth of a 103-104 km2 catchment drained by the Chixoy River in Guatemala. The catchment covers a large part of a 50 km wide orogen located astride the North American - Caribbean plates boundary (Sierra de las Minas - Sierra de Chuacus range). The range is wrenched by sinistral tectonics with a varying amount of transpression and transtension. On the northern flank of this range, the Polochic Fault (PF) accumulated 130 km of total strike-slip displacement, but the Chixoy River only displays a 25 km tectonic bend. Geological evidence indicates that the river probably experienced a diversion that reset earlier tectonic bending. Upstream, the catchment stands out as a large (110x30 km) zone of enhanced erosion (2500 km3 removed since the Middle Miocene). The catchment retains many paleovalleys that we use as markers to track drainage rearrangement, bedrock deformation and changes in erosion rates. Study of the paleovalleys includes: satellite image detection, field mapping of river deposits, analyses of grain-size, clast provenance, heavy mineral provenance, deposit architecture, geochemical analyses, Ar40 -Ar39 dating of volcanic tuffs, 10 Be-26 Al burial dating, and apatite He cooling ages of the bedrock. Coupled analyses of erosion and drainage rearrangement show that, in the studied case, catchment growth occurred over 107 years. Most of the catchment erosion and growth is attributable to uplift along the PF rather than strike-slip motion, although both motion types contribute to the rearrangement. Growth of the catchment is strongly catalyzed by a wealth of other factors, such as river avulsion, volcanism, karstic flow, phreatic flow, and aridity resulting from catchment deepening.

Surgical vs ultrasound-guided drainage of deep neck space abscesses: a randomized controlled trial: surgical vs ultrasound drainage.

PubMed

Biron, Vincent L; Kurien, George; Dziegielewski, Peter; Barber, Brittany; Seikaly, Hadi

2013-02-26

Deep neck space abscesses (DNAs) are relatively common otolaryngology-head and neck surgery emergencies and can result in significant morbidity with potential mortality. Traditionally, surgical incision and drainage (I&D) with antibiotics has been the mainstay of treatment. Some reports have suggested that ultrasound-guided drainage (USD) is a less invasive and effective alternative in select cases. To compare I&D vs USD of well-defined DNAs, using a randomized controlled clinical trial design. The primary outcome measure was effectiveness (length of hospital stay (LOHS) and safety), and the secondary outcome measure was overall cost to the healthcare system. Patients presenting to the University of Alberta Emergency Department with a well-defined deep neck space abscess were recruited in the study. Patients were randomized to surgical or US-guided drainage, placed on intravenous antibiotics and admitted with airway precautions. Following drainage with either intervention, abscess collections were cultured and drains were left in place until discharge. Seventeen patients were recruited in the study. We found a significant difference in mean LOHS between patients who underwent USD (3.1 days) vs I&D (5.2 days). We identified significant cost savings associated with USD with a 41% cost reduction in comparison to I&D. USD drainage of deep neck space abscesses in a certain patient population is effective, safe, and results in a significant cost savings to the healthcare system.

Dredging effects on selected nutrient concentrations and ecoenzymatic activity in two drainage ditch sediments in the lower Mississippi River Valley

USDA-ARS?s Scientific Manuscript database

Agricultural drainage ditches are conduits between production acreage and receiving aquatic systems. Often overlooked for their mitigation capabilities, agricultural drainage ditches provide an important role for nutrient transformation via microbial metabolism. Variations in ecoenzyme activities ...

Comparison of Small Bore Catheter Aspiration and Chest Tube Drainage in the Management of Spontaneous Pneumothorax.

PubMed

Korczyński, P; Górska, K; Nasiłowski, J; Chazan, R; Krenke, R

2015-01-01

Beside standard chest tube drainage other less invasive techniques have been used in the management of patients with an acute episode of spontaneous pneumothorax. The aim of the study was to evaluate the short term effect of spontaneous pneumothorax treatment with small-bore pleural catheter and manual aspiration as compared to large-bore chest tube drainage. Patients with an episode of pneumothorax who required pleural intervention were enrolled in the study and randomly assigned to one of the treatment arms: (1) small-bore pleural catheter (8 Fr) with manual aspiration; (2) standard chest tube drainage (20-24 Fr). Success rate of the first line treatment, duration of catheter or chest tube drainage, and the need for surgical intervention were the outcome measures. The study group included 49 patients (mean age 46.9±21.3 years); with 22 and 27 allocated to small bore manual aspiration and chest tube drainage groups, respectively. There were no significant differences in the baseline characteristics of patients in both therapeutic arms. First line treatment success rates were 64% and 82% in the manual aspiration and chest tube drainage groups, respectively; the difference was insignificant. Median time of treatment with small bore catheter was significantly shorter than conventional chest tube drainage (2.0 vs. 6.0 days; p<0.05). Our results show that treatment of spontaneous pneumothorax with small-bore pleural catheter and manual aspiration might be similarly effective as is chest tube drainage in terms of immediate lung re-expansion.

Spatio-Temporal Changes of Lymphatic Contractility and Drainage Patterns following Lymphadenectomy in Mice

PubMed Central

Kwon, Sunkuk; Agollah, Germaine D.; Wu, Grace; Sevick-Muraca, Eva M.

2014-01-01

Objective To investigate the redirection of lymphatic drainage post-lymphadenectomy using non-invasive near-infrared fluorescence (NIRF) imaging, and to subsequently assess impact on metastasis. Background Cancer-acquired lymphedema arises from dysfunctional fluid transport after lymphadenectomy performed for staging and to disrupt drainage pathways for regional control of disease. However, little is known about the normal regenerative processes of the lymphatics in response to lymphadenectomy and how these responses can be accelerated, delayed, or can impact metastasis. Methods Changes in lymphatic “pumping” function and drainage patterns were non-invasively and longitudinally imaged using NIRF lymphatic imaging after popliteal lymphadenectomy in mice. In a cohort of mice, B16F10 melanoma was inoculated on the dorsal aspect of the paw 27 days after lymphadenectomy to assess how drainage patterns affect metastasis. Results NIRF imaging demonstrates that, although lymphatic function and drainage patterns change significantly in early response to popliteal lymph node (PLN) removal in mice, these changes are transient and regress dramatically due to a high regenerative capacity of the lymphatics and co-opting of collateral lymphatic pathways around the site of obstruction. Metastases followed the pattern of collateral pathways and could be detected proximal to the site of lymphadenectomy. Conclusions Both lymphatic vessel regeneration and co-opting of contralateral vessels occur following lymphadenectomy, with contractile function restored within 13 days, providing a basis for preclinical and clinical investigations to hasten lymphatic repair and restore contractile lymphatic function after surgery to prevent cancer-acquired lymphedema. Patterns of cancer metastasis after lymphadenectomy were altered, consistent with patterns of re-directed lymphatic drainage. PMID:25170770

Mine Water Treatment in Hongai Coal Mines

NASA Astrophysics Data System (ADS)

Dang, Phuong Thao; Dang, Vu Chi

2018-03-01

Acid mine drainage (AMD) is recognized as one of the most serious environmental problem associated with mining industry. Acid water, also known as acid mine drainage forms when iron sulfide minerals found in the rock of coal seams are exposed to oxidizing conditions in coal mining. Until 2009, mine drainage in Hongai coal mines was not treated, leading to harmful effects on humans, animals and aquatic ecosystem. This report has examined acid mine drainage problem and techniques for acid mine drainage treatment in Hongai coal mines. In addition, selection and criteria for the design of the treatment systems have been presented.

Effect of subsurface drainage on the structural capacity of flexible pavement.

DOT National Transportation Integrated Search

2005-01-01

Following the recommendation of the Virginia Transportation Research Council's Pavement Research Advisory Committee, this project was initiated to determine the effectiveness of including subsurface drainage systems in pavements in Virginia. The rese...

Remediation of Acid Mine Drainage with Sulfate Reducing Bacteria

ERIC Educational Resources Information Center

Hauri, James F.; Schaider, Laurel A.

2009-01-01

Sulfate reducing bacteria have been shown to be effective at treating acid mine drainage through sulfide production and subsequent precipitation of metal sulfides. In this laboratory experiment for undergraduate environmental chemistry courses, students design and implement a set of bioreactors to remediate acid mine drainage and explain observed…

Effect of tile effluent on nutrient concentration and retention efficiency in agricultural drainage ditches

USDA-ARS?s Scientific Manuscript database

Tile drainage is a common water management practice in many agricultural landscapes in the Midwestern United States. Drainage ditches regularly receive water from agricultural fields through these tile drains. This field-scale study was conducted to determine the impact of tile discharge on ambient ...

Quantifying subsurface hydrology effects on chemical transport in drainage ditches using a 20-meter flume

USDA-ARS?s Scientific Manuscript database

Agriculture drainage ditches serve as the veins of the Midwestern agricultural landscapes. The transport of chemical fertilizers and pesticides in these ditches affect the local and downstream ecosystems. Although much research has already been conducted on chemical transport in streams and drainage...

Have Metals Lost Their Luster? Environmental Effects Of MIning And Remedial Options

EPA Science Inventory

Many miles of streams in the U.S. (and worldwide) are contaminated by mine-drainage originating from both active and abandoned mining sites [coal and metal mining]. Depending on the host-rock, the drainage might or might not be acidic. Once the drainage mixes with oxygenated st...

Complications in CT-guided procedures: do we really need postinterventional CT control scans?

PubMed

Nattenmüller, Johanna; Filsinger, Matthias; Bryant, Mark; Stiller, Wolfram; Radeleff, Boris; Grenacher, Lars; Kauczor, Hans-Ullrich; Hosch, Waldemar

2014-02-01

The aim of this study is twofold: to determine the complication rate in computed tomography (CT)-guided biopsies and drainages, and to evaluate the value of postinterventional CT control scans. Retrospective analysis of 1,067 CT-guided diagnostic biopsies (n = 476) and therapeutic drainages (n = 591) in thoracic (n = 37), abdominal (n = 866), and musculoskeletal (ms) (n = 164) locations. Severity of any complication was categorized as minor or major. To assess the need for postinterventional CT control scans, it was determined whether complications were detected clinically, on peri-procedural scans or on postinterventional scans only. The complication rate was 2.5 % in all procedures (n = 27), 4.4 % in diagnostic punctures, and 1.0 % in drainages; 13.5 % in thoracic, 2.0 % in abdominal, and 3.0 % in musculoskeletal procedures. There was only 1 major complication (0.1 %). Pneumothorax (n = 14) was most frequent, followed by bleeding (n = 9), paresthesia (n = 2), material damage (n = 1), and bone fissure (n = 1). Postinterventional control acquisitions were performed in 65.7 % (701 of 1,067). Six complications were solely detectable in postinterventional control acquisitions (3 retroperitoneal bleeds, 3 pneumothoraces); all other complications were clinically detectable (n = 4) and/or visible in peri-interventional controls (n = 21). Complications in CT-guided interventions are rare. Of these, thoracic interventions had the highest rate, while pneumothoraces and bleeding were most frequent. Most complications can be detected clinically or peri-interventionally. To reduce the radiation dose, postinterventional CT controls should not be performed routinely and should be restricted to complicated or retroperitoneal interventions only.

A wireless monitoring system for Hydrocephalus shunts.

PubMed

Narayanaswamy, A; Nourani, M; Tamil, L; Bianco, S

2015-08-01

Patients with Hydrocephalus are usually treated by diverting the excess Cerebrospinal Fluid (CSF) to other parts of the body using shunts. More than 40 percentage of shunts implanted fail within the first two years. Obstruction in the shunts is one of the major causes of failure (45 percent) and the detection of obstruction reduces the complexity of the revision surgery. This paper describes a proposed wireless monitoring system for clog detection and flow measurement in shunts. A prototype was built using multiple pressure sensors along the shunt catheters for sensing the location of clog and flow rate. Regular monitoring of flow rates can be used to adjust the valve in the shunt to prevent over drainage or under drainage of CSF. The accuracy of the flow measurement is more than 90 percent.

Drainage capture and discharge variations driven by glaciation in the Southern Alps, New Zealand

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

Ann V. Rowan; Mitchell A. Plummer; Simon H. Brocklehurst

Sediment flux in proglacial fluvial settings is primarily controlled by discharge, which usually varies predictably over a glacial–interglacial cycle. However, glaciers can flow against the topographic gradient to cross drainage divides, reshaping fluvial drainage networks and dramatically altering discharge. In turn, these variations in discharge will be recorded by proglacial stratigraphy. Glacial-drainage capture often occurs in alpine environments where ice caps straddle range divides, and more subtly where shallow drainage divides cross valley floors. We investigate discharge variations resulting from glacial-drainage capture over the past 40 k.y. for the adjacent Ashburton, Rangitata, and Rakaia basins in the Southern Alps, Newmore » Zealand. Although glacial-drainage capture has previously been inferred in the range, our numerical glacier model provides the first quantitative demonstration that this process drives larger variations in discharge for a longer duration than those that occur due to climate change alone. During the Last Glacial Maximum, the effective drainage area of the Ashburton catchment increased to 160% of the interglacial value with drainage capture, driving an increase in discharge exceeding that resulting from glacier recession. Glacial-drainage capture is distinct from traditional (base level–driven) drainage capture and is often unrecognized in proglacial deposits, complicating interpretation of the sedimentary record of climate change.« less

Assessment of the service performance of drainage system and transformation of pipeline network based on urban combined sewer system model.

PubMed

Peng, Hai-Qin; Liu, Yan; Wang, Hong-Wu; Ma, Lu-Ming

2015-10-01

In recent years, due to global climate change and rapid urbanization, extreme weather events occur to the city at an increasing frequency. Waterlogging is common because of heavy rains. In this case, the urban drainage system can no longer meet the original design requirements, resulting in traffic jams and even paralysis and post a threat to urban safety. Therefore, it provides a necessary foundation for urban drainage planning and design to accurately assess the capacity of the drainage system and correctly simulate the transport effect of drainage network and the carrying capacity of drainage facilities. This study adopts InfoWorks Integrated Catchment Management (ICM) to present the two combined sewer drainage systems in Yangpu District, Shanghai (China). The model can assist the design of the drainage system. Model calibration is performed based on the historical rainfall events. The calibrated model is used for the assessment of the outlet drainage and pipe loads for the storm scenario currently existing or possibly occurring in the future. The study found that the simulation and analysis results of the drainage system model were reliable. They could fully reflect the service performance of the drainage system in the study area and provide decision-making support for regional flood control and transformation of pipeline network.

Pseudocyst in the pancreatic tail associated with chronic pancreatitis successfully treated by transpapillary cyst drainage.

PubMed

Naitoh, Itaru; Ohara, Hirotaka; Okayama, Yasutaka; Nakazawa, Takahiro; Ando, Tomoaki; Hayashi, Kazuki; Okumura, Fumihiro; Kitajima, Yasuhiro; Ban, Tessin; Miyabe, Katsuyuki; Ueno, Koichiro; Joh, Takashi; Sano, Hitoshi

2008-09-01

We report a 50-year-old male with pseudocysts in the pancreatic tail associated with chronic pancreatitis successfully treated by transpapillary cyst drainage. He had previously undergone ultrasonography-guided percutaneous cyst drainage for a pancreatic pseudocyst in our hospital. He was readmitted due to abdominal pain and fever. Computed tomography showed recurrence of a pseudocyst in the pancreatic tail measuring 5 cm in diameter. Since conservative treatment failed, endoscopic retrograde pancreatography was performed. There was communication between the pseudocyst and the main pancreatic duct, and pancreatic duct stenosis proximal to the pseudocyst. First, transpapillary pancreatic duct drainage was performed using a plastic stent, but the pseudocyst did not decrease in size and became infected. After removal of the stent, a pigtail type nasocystic catheter was placed in the pseudocyst via the pancreatic duct. The pseudocyst infection immediately disappeared, and the pseudocyst gradually decreased and disappeared. After removal of the nasocystic catheter, no recurrence was observed. As transpapillary drainage of pancreatic pseudocyst, cyst drainage and pancreatic duct drainage have been reported. In our patient with pseudocyst in the pancreatic tail, duct drainage was ineffective and the pseudocyst was infected, whereas cyst drainage was very effective. We considered that cyst drainage by a nasocystic catheter was the first-line therapy as the transpapillary drainage of the pancreatic pseudocyst.

Treatment of posthemorrhagic hydrocephalus in premature infants with subcutaneous reservoir drainage.

PubMed

Yu, Bo; Li, Shasha; Lin, Zhenlang; Zhang, Nu

2009-01-01

To investigate the effectiveness of subcutaneous reservoir drainage as a treatment for the different types of posthemorrhagic hydrocephalus in premature infants. 11 premature infants with posthemorrhagic hydrocephalus underwent subcutaneous reservoir embedment surgery, and cerebrospinal fluid (CSF) was drained via the reservoir intermittently for 8 weeks. During the period of drainage, ultrasound and computerized tomography were used to measure ventricle size. CSF examinations were performed routinely to assess the presence of intraventricular hemorrhage (IVH) and/or infection. (1) Five infants were diagnosed as having obstructive hydrocephalus; 2 had nearly normal ventricle sizes with treatment and drainage was stopped after 8 weeks, 2 had nearly normal ventricle sizes after 4 more weeks of drainage, and 1 underwent ventriculoperitoneal shunt (V-P shunt) surgery due to failure of ventricle size reduction. (2) Six infants were diagnosed as having communicating hydrocephalus; 4 had further enlarged ventricle size after 8 weeks and underwent V-P shunt surgery, 1 had treatment aborted at week 8 of drainage, and only 1 had moderate reduction of ventricle size after 8 weeks. (3) None of the 11 infants had progressive IVH and/or intracranial infection during drainage. Subcutaneous reservoir drainage is a suitable and safe treatment for posthemorrhagic hydrocephalus in premature infants. It is more effective for obstructive hydrocephalus than for communicating hydrocephalus. Copyright (c) 2009 S. Karger AG, Basel.

Cost-Effectiveness Analysis of Surface Flow Constructed Wetlands (SFCW) for Nutrient Reduction in Drainage Discharge from Agricultural Fields in Denmark.

PubMed

Gachango, F G; Pedersen, S M; Kjaergaard, C

2015-12-01

Constructed wetlands have been proposed as cost-effective and more targeted technologies in the reduction of nitrogen and phosphorous water pollution in drainage losses from agricultural fields in Denmark. Using two pig farms and one dairy farm situated in a pumped lowland catchment as case studies, this paper explores the feasibility of implementing surface flow constructed wetlands (SFCW) based on their cost effectiveness. Sensitivity analysis is conducted by varying the cost elements of the wetlands in order to establish the most cost-effective scenario and a comparison with the existing nutrients reduction measures carried out. The analyses show that the cost effectiveness of the SFCW is higher in the drainage catchments with higher nutrient loads. The range of the cost effectiveness ratio on nitrogen reduction differs distinctively with that of catch crop measure. The study concludes that SFCW could be a better optimal nutrients reduction measure in drainage catchments characterized with higher nutrient loads.

Role of percutaneous abscess drainage in the management of young patients with Crohn disease.

PubMed

Pugmire, Brian S; Gee, Michael S; Kaplan, Jess L; Hahn, Peter F; Doody, Daniel P; Winter, Harland S; Gervais, Debra A

2016-05-01

Intra-abdominal abscess is a common complication of Crohn disease in children. Prior studies, primarily in adults, have shown that percutaneous abscess drainage is a safe and effective treatment for this condition; however, the data regarding this procedure and indications in pediatric patients is limited. Our aim was to determine the success rate of percutaneous abscess drainage for abscesses related to Crohn disease in pediatric patients with a focus on treatment endpoints that are relevant in the era of biological medical therapy. We retrospectively reviewed 25 cases of patients ages ≤20 years with Crohn disease who underwent percutaneous abscess drainage. Technical success was defined as catheter placement within the abscess with reduction in abscess size on post-treatment imaging. Clinical success was defined as (1) no surgery within 1 year of drainage or (2) surgical resection following drainage with no residual abscess at surgery or on preoperative imaging. Multiple clinical parameters were analyzed for association with treatment success or failure. All cases were classified as technical successes. Nineteen cases were classified as clinical successes (76%), including 7 patients (28%) who required no surgery within 1 year of percutaneous drainage and 12 patients (48%) who had elective bowel resection within 1 year. There was a statistically significant association between resumption of immunosuppressive therapy within 8 weeks of drainage and both clinical success (P < 0.01) and avoidance of surgery after 1 year (P < 0.01). Percutaneous abscess drainage is an effective treatment for Crohn disease-related abscesses in pediatric patients. Early resumption of immunosuppressive therapy is statistically associated with both clinical success and avoidance of bowel resection, suggesting a role for percutaneous drainage in facilitating prompt initiation of medical therapy and preventing surgical bowel resection.

Drainage and tillage practices in the winter fallow season mitigate CH4 and N2O emissions from a double-rice field in China

NASA Astrophysics Data System (ADS)

Zhang, Guangbin; Yu, Haiyang; Fan, Xianfang; Yang, Yuting; Ma, Jing; Xu, Hua

2016-09-01

Traditional land management (no tillage, no drainage, NTND) during the winter fallow season results in substantial CH4 and N2O emissions from double-rice fields in China. A field experiment was conducted to investigate the effects of drainage and tillage during the winter fallow season on CH4 and N2O emissions and to develop mitigation options. The experiment had four treatments: NTND, NTD (drainage but no tillage), TND (tillage but no drainage), and TD (both drainage and tillage). The study was conducted from 2010 to 2014 in a Chinese double-rice field. During winter, total precipitation and mean daily temperature significantly affected CH4 emission. Compared to NTND, drainage and tillage decreased annual CH4 emissions in early- and late-rice seasons by 54 and 33 kg CH4 ha-1 yr-1, respectively. Drainage and tillage increased N2O emissions in the winter fallow season but reduced it in early- and late-rice seasons, resulting in no annual change in N2O emission. Global warming potentials of CH4 and N2O emissions were decreased by 1.49 and 0.92 t CO2 eq. ha-1 yr-1, respectively, and were reduced more by combining drainage with tillage, providing a mitigation potential of 1.96 t CO2 eq. ha-1 yr-1. A low total C content and high C / N ratio in rice residues showed that tillage in the winter fallow season reduced CH4 and N2O emissions in both early- and late-rice seasons. Drainage and tillage significantly decreased the abundance of methanogens in paddy soil, and this may explain the decrease of CH4 emissions. Greenhouse gas intensity was significantly decreased by drainage and tillage separately, and the reduction was greater by combining drainage with tillage, resulting in a reduction of 0.17 t CO2 eq. t-1. The results indicate that drainage combined with tillage during the winter fallow season is an effective strategy for mitigating greenhouse gas releases from double-rice fields.

Ground-water quality in the western part of the Cambrian-Ordovician aquifer in the Western Lake Michigan Drainages, Wisconsin and Michigan

USGS Publications Warehouse

Saad, D.A.

1996-01-01

Seven pesticides or metabolites were detected in ground-water samples, and at least one pesticide was detected in samples from 24 percent (7 of 29) of wells. Most of the pesticides were detected at low concentrations and were from wells in the regionally unconfined, agricultural, southwest part of the study area. Atrazine was the most commonly detected pesticide and was typically detected in samples from wells that produced modern water.

Endoscopic ultrasonography guided drainage: Summary of consortium meeting, May 21, 2012, San Diego, California

PubMed Central

Kahaleh, Michel; Artifon, Everson LA; Perez-Miranda, Manuel; Gaidhane, Monica; Rondon, Carlos; Itoi, Takao; Giovannini, Marc

2015-01-01

Endoscopic retrograde cholangiopancreatography (ERCP) is the preferred procedure for biliary and pancreatic drainage. While ERCP is successful in about 95% of cases, a small subset of cases are unsuccessful due to altered anatomy, peri-ampullary pathology, or malignant obstruction. Endoscopic ultrasound-guided drainage is a promising technique for biliary, pancreatic and recently gallbladder decompression, which provides multiple advantages over percutaneous or surgical biliary drainage. Multiple retrospective and some prospective studies have shown endoscopic ultrasound-guided drainage to be safe and effective. Based on the currently reported literature, regardless of the approach, the cumulative success rate is 84%-93% with an overall complication rate of 16%-35%. endoscopic ultrasound-guided drainage seems a viable therapeutic modality for failed conventional drainage when performed by highly skilled advanced endoscopists at tertiary centers with expertise in both echo-endoscopy and therapeutic endoscopy PMID:25624708

The application of peritoneal drainage in the surgical treatment for neonates with necrotizing enterocolitis

NASA Astrophysics Data System (ADS)

Zhao, Jixue; Fu, Xin

2017-08-01

Object To explore the feasibility and effects of peritoneal drainage in the surgical treatment for the neonates with necrotizing enterocolitis. Methods: A retrospective analysis was conduct on 32 cases of newborns with extensive and multiple intestinal necrosis found intraoperatively, all of which could not accept first-stage resected, treated by traditional operation or by peritoneal drainage between January, 2013 to January 2017. Duration of operation, amount of bleeding, and the survival rate after operation were compared between the two groups, which were divided by surgical methods. Results: No significant difference was observed in age, and gender (P>0.05) between the two groups. However, duration of operation was significantly shorter, the amount of bleeding was significantly lessen, the survival rate was significantly higher in the patients by peritoneal drainage than the patients by traditional operation (P<0.05). Conclusion: To compare traditional operation or peritoneal drainage in neonates, a retrospective analysis conducted by us showed the feasibility and effects of peritoneal drainage in neonates, and a significant advantage in duration of operation and the survival rate after operation.

Surgical vs ultrasound-guided drainage of deep neck space abscesses: a randomized controlled trial: surgical vs ultrasound drainage

PubMed Central

2013-01-01

Introduction Deep neck space abscesses (DNAs) are relatively common otolaryngology-head and neck surgery emergencies and can result in significant morbidity with potential mortality. Traditionally, surgical incision and drainage (I&D) with antibiotics has been the mainstay of treatment. Some reports have suggested that ultrasound-guided drainage (USD) is a less invasive and effective alternative in select cases. Objectives To compare I&D vs USD of well-defined DNAs, using a randomized controlled clinical trial design. The primary outcome measure was effectiveness (length of hospital stay (LOHS) and safety), and the secondary outcome measure was overall cost to the healthcare system. Methods Patients presenting to the University of Alberta Emergency Department with a well-defined deep neck space abscess were recruited in the study. Patients were randomized to surgical or US-guided drainage, placed on intravenous antibiotics and admitted with airway precautions. Following drainage with either intervention, abscess collections were cultured and drains were left in place until discharge. Results Seventeen patients were recruited in the study. We found a significant difference in mean LOHS between patients who underwent USD (3.1 days) vs I&D (5.2 days). We identified significant cost savings associated with USD with a 41% cost reduction in comparison to I&D. Conclusions USD drainage of deep neck space abscesses in a certain patient population is effective, safe, and results in a significant cost savings to the healthcare system. PMID:23672735

Effects of pleural effusion drainage on oxygenation, respiratory mechanics, and hemodynamics in mechanically ventilated patients.

PubMed

Razazi, Keyvan; Thille, Arnaud W; Carteaux, Guillaume; Beji, Olfa; Brun-Buisson, Christian; Brochard, Laurent; Mekontso Dessap, Armand

2014-09-01

In mechanically ventilated patients, the effect of draining pleural effusion on oxygenation is controversial. We investigated the effect of large pleural effusion drainage on oxygenation, respiratory function (including lung volumes), and hemodynamics in mechanically ventilated patients after ultrasound-guided drainage. Arterial blood gases, respiratory mechanics (airway, pleural and transpulmonary pressures, end-expiratory lung volume, respiratory system compliance and resistance), and hemodynamics (blood pressure, heart rate, and cardiac output) were recorded before and at 3 and 24 hours (H24) after pleural drainage. The respiratory settings were kept identical during the study period. The mean volume of effusion drained was 1,579 ± 684 ml at H24. Uncomplicated pneumothorax occurred in two patients. Respiratory mechanics significantly improved after drainage, with a decrease in plateau pressure and a large increase in end-expiratory transpulmonary pressure. Respiratory system compliance, end-expiratory lung volume, and PaO2/FiO2 ratio all improved. Hemodynamics were not influenced by drainage. Improvement in the PaO2/FiO2 ratio from baseline to H24 was positively correlated with the increase in end-expiratory lung volume during the same time frame (r = 0.52, P = 0.033), but not with drained volume. A high value of pleural pressure or a highly negative transpulmonary pressure at baseline predicted limited lung expansion following effusion drainage. A lesser improvement in oxygenation occurred in patients with ARDS. Drainage of large (≥500 ml) pleural effusion in mechanically ventilated patients improves oxygenation and end-expiratory lung volume. Oxygenation improvement correlated with an increase in lung volume and a decrease in transpulmonary pressure, but was less so in patients with ARDS.

Management of chyle leakage after thyroidectomy, cervical lymph node dissection, in patients with thyroid cancer.

PubMed

Park, Inhye; Her, Nayoon; Choe, Jun-Ho; Kim, Jee Soo; Kim, Jung-Han

2018-01-01

The purpose of this study was to evaluate the incidence and pattern of chyle leakage after thyroidectomy and/or cervical lymph node dissection and to establish management protocols for chyle leakage. Patients who underwent surgical management for thyroid cancer were analyzed retrospectively. For this study, 131 patients with chyle leakage were identified; the overall incidence was 0.9%. Of them, 43.7% of patients underwent central neck dissection without lateral neck dissection, and chyle leakage was easily controlled with conservative management. Patients whose chyle drainage was reduced by >50% after dietary modification had a significantly shorter hospital stay (P < .001); NPO was the most effective dietary modification. The occurrence of chyle leakage after central compartment dissection even without lateral neck dissection was not rare, but was easily controlled with conservative management. Surgical management should be considered if the drainage amount does not decrease by >50% of the original amount of the day of detection after 2 days of NPO. © 2017 Wiley Periodicals, Inc.

Double layer drainage performance of porous asphalt pavement

NASA Astrophysics Data System (ADS)

Ji, Yangyang; Xie, Jianguang; Liu, Mingxi

2018-06-01

In order to improve the design reliability of the double layer porous asphalt pavement, the 3D seepage finite element method was used to study the drainage capacity of double layer PAC pavements with different geometric parameters. It revealed that the effect of pavement drainage length, slope, permeability coefficient and structure design on the drainage capacity. The research of this paper can provide reference for the design of double layer porous asphalt pavement in different rainfall intensity areas, and provide guides for the related engineering design.

Investigation of ground-water contamination at a drainage ditch, Installation Restoration Site 4, Naval Air Station Corpus Christi, Corpus Christi, Texas, 2005–06

USGS Publications Warehouse

Vroblesky, Don A.; Casey, Clifton C.

2007-01-01

The U.S. Geological Survey, in cooperation with the Naval Facilities Engineering Command Southeast, used newly developed sampling methods to investigate ground-water contamination by chlorobenzenes beneath a drainage ditch on the southwestern side of Installation Restoration Site 4, Naval Air Station Corpus Christi, Corpus Christi, Texas, during 2005-06. The drainage ditch, which is a potential receptor for ground-water contaminants from Installation Restoration Site 4, intermittently discharges water to Corpus Christi Bay. This report uses data from a new type of pore-water sampler developed for this investigation and other methods to examine the subsurface contamination beneath the drainage ditch. Analysis of ground water from the samplers indicated that chlorobenzenes (maximum detected concentration of 160 micrograms per liter) are present in the ground water beneath the ditch. The concentrations of dissolved oxygen in the samples (less than 0.05-0.4 milligram per liter) showed that the ground water beneath and near the ditch is anaerobic, indicating that substantial chlorobenzene biodegradation in the aquifer beneath the ditch is unlikely. Probable alternative mechanisms of chlorobenzene removal in the ground water beneath the drainage ditch include sorption onto the organic-rich sediment and contaminant depletion by cattails through uptake, sorption, and localized soil aeration.

Improved Intermittent-clamped Drainage in Lower Lumbar Internal Fixation: A Randomized Prospective Study

PubMed Central

Hao, Qing-Ying; Liu, Chu-Yin; Fu, Chan-Juan; Zhang, Xiao-Hua; Tan, Ming-Sheng

2016-01-01

Background: Continuous negative pressure drainage (CNPD) is widely used after lower lumbar internal fixation; however, it may cause tremendous blood loss and lead to postoperative hemorrhagic anemia. The present study explored the efficacy and safety of improved intermittent-clamped drainage (ICD) for lower lumbar internal fixation. Methods: This was a prospective study that included 156 patients with decompression of the spinal canal and internal fixation for the first time from January 2012 to December 2014. The patients were randomly divided into ICD group and CNPD group, and each group had 78 cases. A drainage tube was placed under the deep fascia in all patients within 10 min after the commencement of wound closure. The postoperative drainage amount at different time points, the hemoglobin level, and postoperative complications were recorded and compared between the two groups. Shapiro-Wilk test, independent samples t-test, and Mann-Whitney U-test were used in this study. Results: The drainage amount was significantly reduced in the ICD group, as compared with the CNPD group (Z = 10.74, P < 0.01). The mean total drainage amount (in ml) of the single-segment and two-segment procedures was significantly greater in the CNPD group than the ICD group (Z = 10.63 and 10.75, respectively; P < 0.01). For the adverse events, there was no significant difference in postoperative temperature, wound problem, and complications between the two groups. Conclusions: The present study showed a statistically significant reduction in postoperative drainage amount between ICD and CNPD groups, and ICD is an effective, convenient, and safe method for routine use in lower lumbar surgery. It is essential to focus on the effect of clamping drainage with long-segment surgical procedure and complex lumbar disease in the further investigation, as well as the effect of clamping on long-term functional outcomes. PMID:27900992

The role of algae in mine drainage bioremediation

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

Davison, J.

1990-06-01

The effect of mine drainage effluent on aquatic ecosystems has been abundantly documented and remediation efforts to data have always been costly and temporary at best. Bioremediation, using natural environmental microbes, to treat acid mine drainage has shown great promise as an affordable, permanent treatment. At Lambda, we used mixatrophic cultures of bacteria, algae, protozoans and fungal groups on four different jobs and it has proven effective. The role of two particular algal groups, the Euglena mutabilis and the Ochramonas sp. are particularly of phycological interest.

Landscape effects of wildfire on permafrost distribution in interior Alaska derived from remote sensing

USGS Publications Warehouse

Brown, Dana R. N.; Jorgenson, M. Torre; Kielland, Knut; Verbyla, David L.; Prakash, Anupma; Koch, Joshua C.

2016-01-01

Climate change coupled with an intensifying wildfire regime is becoming an important driver of permafrost loss and ecosystem change in the northern boreal forest. There is a growing need to understand the effects of fire on the spatial distribution of permafrost and its associated ecological consequences. We focus on the effects of fire a decade after disturbance in a rocky upland landscape in the interior Alaskan boreal forest. Our main objectives were to (1) map near-surface permafrost distribution and drainage classes and (2) analyze the controls over landscape-scale patterns of post-fire permafrost degradation. Relationships among remote sensing variables and field-based data on soil properties (temperature, moisture, organic layer thickness) and vegetation (plant community composition) were analyzed using correlation, regression, and ordination analyses. The remote sensing data we considered included spectral indices from optical datasets (Landsat 7 Enhanced Thematic Mapper Plus (ETM+) and Landsat 8 Operational Land Imager (OLI)), the principal components of a time series of radar backscatter (Advanced Land Observing Satellite—Phased Array type L-band Synthetic Aperture Radar (ALOS-PALSAR)), and topographic variables from a Light Detection and Ranging (LiDAR)-derived digital elevation model (DEM). We found strong empirical relationships between the normalized difference infrared index (NDII) and post-fire vegetation, soil moisture, and soil temperature, enabling us to indirectly map permafrost status and drainage class using regression-based models. The thickness of the insulating surface organic layer after fire, a measure of burn severity, was an important control over the extent of permafrost degradation. According to our classifications, 90% of the area considered to have experienced high severity burn (using the difference normalized burn ratio (dNBR)) lacked permafrost after fire. Permafrost thaw, in turn, likely increased drainage and resulted in drier surface soils. Burn severity also influenced plant community composition, which was tightly linked to soil temperature and moisture. Overall, interactions between burn severity, topography, and vegetation appear to control the distribution of near-surface permafrost and associated drainage conditions after disturbance.

Unilateral improvement in glomerular filtration rate after permanent drainage of a perinephric pseudocyst in a cat.

PubMed

McCord, Kelly; Steyn, Philip F; Lunn, Katharine F

2008-07-01

A 12-year-old, 6 kg, castrated male Siamese-cross cat was referred for investigation of an abdominal mass. The cat was found to have a left perinephric pseudocyst (PNP), accompanied by azotemia, with a small right kidney detected on ultrasound. Glomerular filtration rate (GFR) was determined by renal scintigraphy and was found to be low, with the left kidney contributing 64% of the total GFR. Percutaneous ultrasound-guided drainage of the PNP did not improve the GFR, and fluid reaccumulated within a short period of time. Laparoscopic fenestration of the cyst capsule was performed to allow for permanent drainage. The PNP did not recur, renal values progressively improved, and 8 months after the capsulotomy the GFR of the left kidney had increased by 50%, while renal function remained static on the right side.

Environmental DNA assays for the sister taxa sauger (Sander canadensis) and walleye (Sander vitreus)

PubMed Central

Carim, Kellie J.; Ruggles, Michael; McKelvey, Kevin S.; Young, Michael K.; Schwartz, Michael K.

2017-01-01

Sauger (Sander canadensis) and walleye (S. vitreus) are percid fishes that naturally co-occur throughout much of the eastern United States. The native range of sauger extends into the upper Missouri River drainage where walleye did not historically occur, but have been stocked as a sport fish. Sauger populations have been declining due to habitat loss, fragmentation, and competition with non-native species, such as walleye. To effectively manage sauger populations, it is necessary to identify areas where sauger occur, and particularly where they co-occur with walleye. We developed quantitative PCR assays that can detect sauger and walleye DNA in filtered water samples. Each assay efficiently detected low quantities of target DNA and failed to detect DNA of non-target species with which they commonly co-occur. PMID:28441436

Water-Quality Conditions and Constituent Loads, Water Years 1996-2002, and Water-Quality Trends, Water Years 1983-2002, in the Scituate Reservoir Drainage Area, Rhode Island

USGS Publications Warehouse

Nimiroski, Mark T.; DeSimone, Leslie A.; Waldron, Marcus C.

2008-01-01

The Scituate Reservoir is the primary source of drinking water for more than 60 percent of the population of Rhode Island. Water-quality data and streamflow data collected at 37 surface-water monitoring stations in the Scituate Reservoir drainage area, Rhode Island, from October 1, 1995 through September 30, 2002, (water years (WY) 1996-2002) were analyzed to determine water-quality conditions and constituent loads in the drainage area. Trends in water quality, including physical properties and concentrations of constituents, were investigated for the same period and for a longer period from October 1, 1982 through September 30, 2002 (WY 1983-2002). Water samples were collected and analyzed by Providence Water Supply Board, the agency that manages the Scituate Reservoir. Streamflow data were collected by the U.S. Geological Survey. Median values and other summary statistics were calculated for WY 1996-2002 for all 37 monitoring stations for pH, color, turbidity, alkalinity, chloride, nitrite, nitrate, total coliform bacteria, Escherichia coli (E. coli) bacteria, orthophosphate, iron, and manganese. Instantaneous loads and yields (loads per unit area) of total coliform and E. coli bacteria (indicator bacteria), chloride, nitrite, nitrate, orthophosphate, iron, and manganese were calculated for all sampling dates during WY 1996-2002 for the 23 stations with streamflow data. Values of physical properties and concentrations of constituents were compared to State and Federal water-quality standards and guidelines, and were related to streamflow, land-use characteristics, and road density. Tributary stream water in the Scituate Reservoir drainage area for WY 1996-2002 was slightly acidic (median pH of all stations equal to 6.1) and contained low concentrations of chloride (median 13 milligrams per liter (mg/L)), nitrate (median 0.04 mg/L as N), and orthophosphate (median 0.04 mg/L as P). Turbidity and alkalinity values also were low with median values of 0.62 nephelometric turbidity units and 4.8 mg/L as calcium carbonate, respectively. Indicator bacteria were detected in samples from all stations, but median concentrations were low, 23 and 9 colony-forming units per 100 mL for total coliform and E. coli bacteria, respectively. Median values of several physical properties and median concentrations of several constituents that can be related to human activities correlated positively with the percentages of developed land and correlated negatively with the percentages of forest cover in the drainage areas of the monitoring stations. Median concentrations of chloride also correlated positively with the density of roads in the drainage areas of monitoring stations, likely reflecting the effects of road-salt applications. Median values of color correlated positively with the percentages of wetlands in the drainage areas of monitoring stations, reflecting the natural sources of color in tributary stream waters. Negative correlations of turbidity, indicator bacteria, and chloride with streamflow likely reflect seasonal patterns, in which higher values and concentrations of these properties and constituents occur during low-flow conditions at the ends of water years. Similar seasonal patterns were observed for pH, alkalinity, and color. Loads and yields of chloride, nitrate, orthophosphate, and bacteria varied among monitoring stations in the Scituate Reservoir drainage area. Loads generally were higher at stations with larger drainage areas and at stations in the eastern, more developed parts of the Scituate Reservoir drainage area. Yields generally were higher at stations in the eastern parts of the drainage area. Upward trends in pH were identified for nearly half the monitoring stations and may reflect regional reductions in acid precipitation. Upward and downward trends were identified in chloride concentrations at various stations; upward trends may reflect the effects of increasing development, whereas strong downward trends at

Genetic variation in chinook, Oncorhynchus tshawytscha, and coho, O. Kisutch

USGS Publications Warehouse

Reisenbichler, R.R.; Phelps, S.R.

1987-01-01

We used starch-gel electrophoresis to genetically characterize the populations of chinook salmon, Oncorhynchus tshawytscha, and coho salmon, O. kisutch, in the major drainages of the north coast of Washington (the Quillayute, Uoh, Queets, and Quinault Rivers). Of 55 loci examined for electrophoretically detectable variation. 6 were polymorphic (frequency of the common allele was less than 0.95) in chinook salmon and 3 in coho salmon. Statistical tests of interdrainage and intradrainage variation for coho salmon were tenuous because most of the fish examined were from a single year class so that we could not account for variation among year classes. Nevertheless, these tests suggested that distinct stocks ofcoho salmon exist within drainages. and that variation was not significantly greater among drainages than within drainages. Interdrainage variation for wild chinook salmon was not significant. The data suggested that summer chinook salmon were electrophoretically different from fall chinook salmon, and the hatchery populations of chinook salmon were distinct from wild fish. A hatchery population developed primarily from north coast fish was electrophoretically more similar to wild chinook salmon than were the others.

After urgent drainage of an obstructed kidney by internal ureteric stenting; is ureteroscopic stone extraction always needed?

PubMed Central

Taha, Diaa-Eldin; Elshal, Ahmed M.; Zahran, Mohamed H.; Harraz, Ahmed M.; El-Nahas, Ahmed R.; Shokeir, Ahmed A.

2015-01-01

Objectives To assess the probability of spontaneous stone passage and its predictors after drainage of obstructed kidney by JJ stent, as insertion of an internal ureteric stent is often used for renal drainage in cases of calcular ureteric obstruction. Patients and methods Between January 2011 and June 2013, patients for whom emergent drainage by ureteric stents were identified. The patients’ demographics, presentation, and stone characteristics were reviewed. The primary endpoint for this study was stone-free status at the time of stent removal, where all patients underwent non-contrast spiral computed tomography (NCCT) before stent removal. Ureteroscopic stone extraction was performed for CT detectable ureteric stones at the time of stent removal. Potential factors affecting the need for ureteroscopic stone extraction at the time of stent removal were assessed using univariate and multivariate statistical analyses. Results Emergent ureteric stents were undertaken in 196 patients (112 males, 84 females) with a mean (SD) age of 53.7 (16.2) years, for renal obstruction drainage. At the time of stent removal, 83 patients (42.3%) were stone free; with the remaining 113 patients (57.7%) undergoing ureteroscopic stone extraction. On multivariate analysis, stone width [odds ratio (OR) 15.849, 95% confidence interval (CI) 2.83; P = 0.002) and radio-opaque stones (OR 12.035, 95% CI 4.65; P < 0.001) were independent predictors of the need for ureteroscopic stone extraction at the time of stent removal. Conclusion Spontaneous ureteric stone passage is possible after emergent drainage of an obstructed kidney by ureteric stenting. Stone opacity, larger stone width, and positive preoperative urine culture are associated with a greater probability of requiring ureteroscopic stone extraction after emergent drainage by ureteric stenting. PMID:26609444

Pseudocyst in the Pancreatic Tail Associated with Chronic Pancreatitis Successfully Treated by Transpapillary Cyst Drainage

PubMed Central

Naitoh, Itaru; Ohara, Hirotaka; Okayama, Yasutaka; Nakazawa, Takahiro; Ando, Tomoaki; Hayashi, Kazuki; Okumura, Fumihiro; Kitajima, Yasuhiro; Ban, Tessin; Miyabe, Katsuyuki; Ueno, Koichiro; Joh, Takashi; Sano, Hitoshi

2008-01-01

We report a 50-year-old male with pseudocysts in the pancreatic tail associated with chronic pancreatitis successfully treated by transpapillary cyst drainage. He had previously undergone ultrasonography-guided percutaneous cyst drainage for a pancreatic pseudocyst in our hospital. He was readmitted due to abdominal pain and fever. Computed tomography showed recurrence of a pseudocyst in the pancreatic tail measuring 5 cm in diameter. Since conservative treatment failed, endoscopic retrograde pancreatography was performed. There was communication between the pseudocyst and the main pancreatic duct, and pancreatic duct stenosis proximal to the pseudocyst. First, transpapillary pancreatic duct drainage was performed using a plastic stent, but the pseudocyst did not decrease in size and became infected. After removal of the stent, a pigtail type nasocystic catheter was placed in the pseudocyst via the pancreatic duct. The pseudocyst infection immediately disappeared, and the pseudocyst gradually decreased and disappeared. After removal of the nasocystic catheter, no recurrence was observed. As transpapillary drainage of pancreatic pseudocyst, cyst drainage and pancreatic duct drainage have been reported. In our patient with pseudocyst in the pancreatic tail, duct drainage was ineffective and the pseudocyst was infected, whereas cyst drainage was very effective. We considered that cyst drainage by a nasocystic catheter was the first-line therapy as the transpapillary drainage of the pancreatic pseudocyst. PMID:21897788

Water-quality assessment of the Albemarle-Pamlico Drainage Basin, North Carolina and Virginia; organochlorine compounds in Asiatic clam (Corbicula fluminea) soft tissues and whole redbrest sunfish (Lepomis auritus) 1992-93

USGS Publications Warehouse

Smith, K.E.; Ruhl, P.M.

1996-01-01

The analysis of potential contaminants in biological tissues is an important part of many water-quality assessment programs, including the National Water-Quality Assessment (NAWQA) Program. Tissue analyses often are used to provide information about (1) direct threats to ecosystem integrity, and (2) the occurrence and distribution of potential contaminants in the environment. During 1992-93, Asiatic clam (Corbicula fluminea) soft tissues and whole redbreast sunfish (Lepomis auritus) samples were collected and analyzed to obtain information about the occurrence and distribution of organochlorine compounds in the Albemarle-Pamlico drainage Basin of North Carolina and Virginia. The investigation was conducted as part of the NAWQA Program. Relatively few organochlorine compounds were detected and of the compounds detected, all were detected in relatively low concentrations. The organochlorine compounds detected were p,p'-DDD, p,p'-DDE, p,p'-DDT, dieldrin, trans-nonachlor, PCB's, and toxaphene. Multiple compounds were detected at 16 of 19 sites sampled. Compared to Asiatic clams, redbreast sunfish appear to be better bioindicators of organochlorine contamination in aquatic systems. Except for one detection of toxaphene, pesticide concentrations are well below the National Academy of Sciences and National Academy of Engineering (NAS/NAE) guidelines for the protection of fish-eating wildlife.

T-tube drainage versus primary closure after laparoscopic common bile duct exploration.

PubMed

Gurusamy, Kurinchi Selvan; Koti, Rahul; Davidson, Brian R

2013-06-21

T-tube drainage may prevent bile leak from the biliary tract following bile duct exploration and it offers post-operative access to the bile ducts for visualisation and exploration. Use of T-tube drainage after laparoscopic common bile duct (CBD) exploration is controversial. To assess the benefits and harms of T-tube drainage versus primary closure after laparoscopic common bile duct exploration. We searched the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library, MEDLINE, EMBASE, and Science Citation Index Expanded until April 2013. We included all randomised clinical trials comparing T-tube drainage versus primary closure after laparoscopic common bile duct exploration. Two of four authors independently identified the studies for inclusion and extracted data. We analysed the data with both the fixed-effect and the random-effects model meta-analyses using Review Manager (RevMan) Analysis. For each outcome we calculated the risk ratio (RR), rate ratio (RaR), or mean difference (MD) with 95% confidence intervals (CI) based on intention-to-treat analysis. We included three trials randomising 295 participants: 147 to T-tube drainage versus 148 to primary closure. All trials had a high risk of bias. No one died during the follow-up period. There was no significant difference in the proportion of patients with serious morbidity (17/147 (weighted percentage 11.3%) in the T-tube drainage versus 9/148 (6.1%) in the primary closure group; RR 1.86; 95% CI 0.87 to 3.96; three trials), and no significant difference was found in the serious morbidity rates (weighted serious morbidity rate = 97 events per 1000 patients) in participants randomised to T-tube drainage versus serious morbidity rate = 61 events per 1000 patients in the primary closure group; RR 1.59; 95% CI 0.66 to 3.83; three trials). Quality of life was not reported in any of the trials. The operating time was significantly longer in the T-tube drainage group compared with the primary closure group (MD 21.22 minutes; 95% CI 12.44 minutes to 30.00 minutes; three trials). The hospital stay was significantly longer in the T-tube drainage group compared with the primary closure group (MD 3.26 days; 95% CI 2.49 days to 4.04 days; three trials). According to one trial, the participants randomised to T-tube drainage returned to work approximately eight days later than the participants randomised to the primary closure group (P < 0.005). T-tube drainage appears to result in significantly longer operating time and hospital stay as compared with primary closure without any evidence of benefit after laparoscopic common bile duct exploration. Based on currently available evidence, there is no justification for the routine use of T-tube drainage after laparoscopic common bile duct exploration in patients with common bile duct stones. More randomised trials comparing the effects of T-tube drainage versus primary closure after laparoscopic common bile duct exploration may be needed. Such trials should be conducted with low risk of bias, assessing the long-term beneficial and harmful effects including long-term complications such as bile stricture and recurrence of common bile duct stones.

The impact of pesticides on the macroinvertebrate community in the water channels of the Río Negro and Neuquén Valley, North Patagonia (Argentina).

PubMed

Macchi, Pablo; Loewy, Ruth Miriam; Lares, Betsabé; Latini, Lorena; Monza, Liliana; Guiñazú, Natalia; Montagna, Cristina Mónica

2018-04-01

Agriculture represents the second most important economic activity in the North Patagonian Region of Argentina and non-selective insecticides are still being used with significant implications to the quality of the environment. The range of concentrations (μg/L) determined for azinphosmethyl, chlorpyrifos, and carbaryl in drainage channels were from non-detected to 1.02, 1.45, and 11.21, respectively. Macroinvertebrate abundance and taxon richness in drainage channels were significantly lower in November compared to the other sampling months (October, February). The decrease in taxon richness observed in November was associated with chlorpyrifos and azinphosmethyl peak concentrations. The most remarkable changes were the decrease in sensitive taxa such as Baetidae and the increase in some tolerant taxa such as Chironomidae and Gastropoda.For all three pesticides, the acute hazard quotient exceeded the risk criteria for invertebrates. The effects of the three pesticides on aquatic organisms, characterized by joint probability curves, showed that the LC 50 of 10% of the species were exceeded five and three times by the concentrations of azinphosmethyl and chlorpyrifos during the study period, respectively. However, the correlation between the pesticide concentrations and both taxon richness and abundance of macroinvertebrates at each site (irrigation and drainage channels) was indicative that only chlorpyrifos was negatively correlated with both parameters (Spearman r 2 - 0.61, p = 0.0051 and Spearman r 2 - 0.59, p = 0.0068 for taxon richness and abundance correlation, respectively). We conclude that macroinvertebrate assemblages in drainage channels were highly affected by chlorpyrifos levels.

Pirfenidone inhibits fibrosis in foreign body reaction after glaucoma drainage device implantation.

PubMed

Jung, Kyoung In; Park, Chan Kee

2016-01-01

The aim of this study was to investigate the antiscarring effects of pirfenidone on foreign body reaction in a rabbit model of glaucoma drainage implant surgery. Adult New Zealand White rabbits had glaucoma drainage device implantation using Model FP8 Ahmed glaucoma valves. One eye was randomly assigned to receive postoperative intrableb injection of pirfenidone followed by topical treatment. The other eye underwent the same procedure but without the addition of pirfenidone. Histochemical staining and immunohistochemistry for blebs were performed. The degree of cellularity was smaller in the pirfenidone group than in the control group at 2 weeks post operation (P=0.005). A few foreign body giant cells were detected in the inner border of the capsule, and their numbers were similar in the control and pirfenidone groups (P>0.05). Using Masson's trichrome stain, the inner collagen-rich layer was found to be thinner in the pirfenidone group than the control group at 4 weeks (P=0.031) and 8 weeks (P=0.022) post operation. The percentage of proliferating cell nuclear antigen-positive cells was lower in the pirfenidone group than in the control group at 2 weeks post operation (total bleb, P=0.022; inner bleb, P=0.036). Pirfenidone treatment decreased the immunoreactivity of connective tissue growth factor at 2 weeks post operation (total bleb, P=0.029; inner bleb, P=0.018). The height and area of α-smooth muscle actin expression were lower in the pirfenidone group than the control group at 2 weeks, 4 weeks, and 8 weeks post operation (all P<0.05). Postoperative intrableb injection of pirfenidone followed by topical administration reduced fibrosis following glaucoma drainage device implantation. These findings suggest that pirfenidone may function as an antiscarring treatment in foreign body reaction after tube-shunt surgery.

An investigation of the effects of an arterial drainage scheme on the rainfall-runoff transformation behaviour of the Brosna catchment in Ireland

NASA Astrophysics Data System (ADS)

Bhattarai, K. P.; O'Connor, K. M.

2003-04-01

Inefficient natural land drainage and the consequent frequent flooding of rivers are a problem of particular significance to the Irish economy. Such problems can be attributed less to the amount of annual rainfall, than to the topological configuration of Ireland. Its high maritime rim and relatively flat interior results in poor river gradients, intercepted by many lakes. As a remedial measure to tackle these problems, Arterial Drainage Schemes (ADSs) were started in Ireland from as early as the beginning of the nineteenth century. The major activities carried out under ADSs have been the deepening and widening of channels to increase their discharge-carrying capacity, which naturally affected the hydrological behaviour of the catchments involved. Earlier studies carried out in order to assess the effects of such ADSs on the hydrological behaviour of Irish catchments were concentrated mainly on comparisons of unit hydrographs and relationship between flood peaks of pre- and post-drainage periods. The present study, carried out on the River Brosna catchment in Ireland, concentrates on assessing the changes in the rainfall runoff transformation process, by using the conceptual Soil Moisture Accounting and Routing Model (SMAR), one of the constituent models of the "Galway River Flow Modelling and Forecasting System (GFMFS)" software package. Hydro-meteorological data of the pre-drainage (1942--1947) and post-drainage (1954--2000) periods have been used in this study. The results of the present study show that, for similar patterns of rainfall, the catchment produces higher annual maximum daily flows, and lower annual minimum daily flows in the post-drainage period than in the pre-drainage period. Moreover, the post-drainage unit hydrographs are more "peaky" and have quicker recessions than the pre-drainage counterparts, thus confirming the findings of the earlier studies. It is also observed that, apart from the expected pre-to-post-drainage change, the nature of the catchment response throughout the post-drainage period has not remained the same as it reverted to pre-drainage-like behaviour after the first one-and-a-half decades (around 1969), indicating that the effects of the ADS had died out over that time. This behaviour was also confirmed by comparing the evolving nature of the unit hydrograph produced for a five-year moving calibration window period from 1959 to 1974. It is unclear at this point whether this change was due to the observed reduction in rainfall in the mid-seventies, inefficient maintenance of the channels, land subsidence following drainage, changes in land use, urbanization, climate change, or some other factors or combinations. The results of the present study further show that, during the nineties, the response pattern changed back again to something akin to early post-drainage-like behaviour, the reason for which is even less clear but obviously can not be attributed to the ADS. Further investigations are currently underway to try to explain such changes in the catchment response to rainfall and also to establish if similar changes occurred on other Irish catchments which also underwent arterial drainage schemes.

Tumors induce coordinate growth of artery, vein, and lymphatic vessel triads.

PubMed

Ruddell, Alanna; Croft, Alexandra; Kelly-Spratt, Karen; Furuya, Momoko; Kemp, Christopher J

2014-05-21

Tumors drive blood vessel growth to obtain oxygen and nutrients to support tumor expansion, and they also can induce lymphatic vessel growth to facilitate fluid drainage and metastasis. These processes have generally been studied separately, so that it is not known how peritumoral blood and lymphatic vessels grow relative to each other. The murine B16-F10 melanoma and chemically-induced squamous cell carcinoma models were employed to analyze large red-colored vessels growing between flank tumors and draining lymph nodes. Immunostaining and microscopy in combination with dye injection studies were used to characterize these vessels. Each peritumoral red-colored vessel was found to consist of a triad of collecting lymphatic vessel, vein, and artery, that were all enlarged. Peritumoral veins and arteries were both functional, as detected by intravenous dye injection. The enlarged lymphatic vessels were functional in most mice by subcutaneous dye injection assay, however tumor growth sometimes blocked lymph drainage to regional lymph nodes. Large red-colored vessels also grew between benign papillomas or invasive squamous cell carcinomas and regional lymph nodes in chemical carcinogen-treated mice. Immunostaining of the red-colored vessels again identified the clustered growth of enlarged collecting lymphatics, veins, and arteries in the vicinity of these spontaneously arising tumors. Implanted and spontaneously arising tumors induce coordinate growth of blood and lymphatic vessel triads. Many of these vessel triads are enlarged over several cm distance between the tumor and regional lymph nodes. Lymphatic drainage was sometimes blocked in mice before lymph node metastasis was detected, suggesting that an unknown mechanism alters lymph drainage patterns before tumors reach draining lymph nodes.

GROUNDWATER IMPACTED BY ACID MINE DRAINAGE

EPA Science Inventory

The generation and release of acidic, metal-rich water from mine wastes continues to be an intractable environmental problem. Although the effects of acid mine drainage (AMD) are most evident in surface waters, there is an obvious need for developing cost-effective approaches fo...

Predictors for Recurrence of Chronic Subdural Hematoma.

PubMed

Hammer, Alexander; Tregubow, Alexander; Kerry, Ghassan; Schrey, Michael; Hammer, Christian; Steiner, Hans-Herbert

2017-01-01

This prospective study was designed to analyze the dependence of different factors on the recurrence rate of chronic subdural hematoma (cSDH) after surgical treatment. Seventy-three consecutive patients, who were surgically treated at our department due to cSDH between 2009 and 2012, were included. The following parameters were analyzed: patient age and gender, occurrence of trauma, time between trauma and admission, neurological symptoms, presence of minor diseases, intake of anticoagulation medication. We classified the results of diagnostic imaging and determined the space-consuming effect via the cerebral midline shift. In addition, we scrutinized intraoperative findings and the dependence of the position of subdural drainage on the recurrence rate of cSDH. In our patient group, cSDH recurrence was significantly associated with aphasia (p=0.008). Moreover an increased cSDH recurrence rate was observed in the patient group that had a separated manifestation of the cSDH in the preoperative diagnostic imaging (p=0.048) and received no drainage implant (p=0.016). Homogeneous isodense cSDH was associated with no apparent recurrence (p=0.037). Within the scope of this study, we detected aphasia and separated cSDH as predictors of cSDH recurrence. Homogeneous isodense cSDH seems to be a good prognostic sign regarding the risk of recurrence development. Furthermore, our data clearly emphasize the importance of surgically applied drainage implants to prevent a recurrence of cSDH.

Hyperammoniemic coma in a patient with ureterosigmoidostomy and normal liver function.

PubMed

Van Laethem, J L; Gay, F; Franck, N; Van Gossum, A

1992-11-01

Hyperammoniemic encephalopathy has been reported after ureterosigmoidostomy. Its development is related to a problem of bacterial overgrowth and, most often, is favored by the presence of an underlying liver dysfunction. We report the case of a 43-year-old woman with a ureterosigmoidostomy done 28 years earlier who developed hyperammoniemic coma induced by an acute rectocolitis and in the absence of any detectable liver dysfunction. Neither administration of Lactilol and neomycin nor rectal tube drainage were effective; systemic antimicrobial therapy effective against the urease-producing gram-negative bacilli was required and led to a decrease in serum ammonia levels and a dramatic clinical improvement.

EXAMPLES OF LANDFILL-GENERATED PLUMES IN LOW-RELIEF AREAS, SOUTHEAST FLORIDA.

USGS Publications Warehouse

Russell, Gary M.; Stewart, Mark; Higer, Aaron L.

1987-01-01

Examples of effects of low topographic relief are noted in southeast Florida where water-table gradients are 7 multiplied by 10** minus **4 to 5 multiplied by 10** minus **4 feet per foot. Water-table mounding beneath the landfill and the drainage effects of nearby ditches and well have created multiple leachate plumes in Stuart where one plume migrated in a direction opposite to the apparent regional gradient. In Coral Springs analysis suggests a bifurcating plume migrating along two narrow zones. In Fort Pierce it was difficult to detect leachate because of mineralized irrigation water and fertilizer runoff from an adjacent citrus grove.

Outcome of transarterial treatment of dural arteriovenous fistulas with direct or indirect cortical venous drainage.

PubMed

Mantilla, Daniel; Le Corre, Marine; Cagnazzo, Federico; Gascou, Gregory; Eker, Omer; Machi, Paolo; Riquelme, Carlos; Dargazanli, Cyril; Costalat, Vincent; Bonafe, Alain; Lefevre, Pierre-Henri

2018-01-30

Transarterial Onyx embolization is an effective treatment for patients with intracranial dural arteriovenous fistula (DAVF). A study was performed to determine whether the clinical and radiological outcomes after transarterial Onyx treatment were affected by the type of cortical venous drainage (direct vs indirect) of high-grade DAVF. Between May 2006 and December 2014, demographic data, clinical presentation, angiographic characteristics, and treatment-related outcomes were collected for 54 patients divided into two groups (intracranial DAVF with direct and indirect cortical venous drainage). Continuous variables were compared with the two-tailed t test and categorical variables with the χ 2 test. Statistical significance was set at P<0.05. Fifty-two patients (71% with direct and 29% with indirect cortical venous drainage) underwent Onyx embolization. Immediate complete occlusion after treatment was observed in about 55% of patients without between-group difference. During the long-term follow-up, complete angiographic occlusion was achieved in 83% of patients. Specifically, 15 additional patients (40%) in the direct cortical venous drainage group progressed to complete occlusion, but only one (6%) in the indirect cortical venous drainage group. Overall, the rate of complete occlusion was higher in patients with DAVF with direct cortical venous drainage (92%) than in those with DAVF with indirect cortical venous drainage (62.5%) (P=0.01). The rate of permanent treatment-related complications was 4%, mostly related to ischemic events. Overall, 80.5% of patients had a good neurological outcome (modified Rankin Scale score 0-2). Transarterial Onyx embolization of intracranial high-grade DAVF is safe and effective, particularly for lesions with direct cortical venous drainage. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Stream-channel and watershed delineations and basin-characteristic measurements using lidar elevation data for small drainage basins within the Des Moines Lobe landform region in Iowa

USGS Publications Warehouse

Eash, David A.; Barnes, Kimberlee K.; O'Shea, Padraic S.; Gelder, Brian K.

2018-02-14

Basin-characteristic measurements related to stream length, stream slope, stream density, and stream order have been identified as significant variables for estimation of flood, flow-duration, and low-flow discharges in Iowa. The placement of channel initiation points, however, has always been a matter of individual interpretation, leading to differences in stream definitions between analysts.This study investigated five different methods to define stream initiation using 3-meter light detection and ranging (lidar) digital elevation models (DEMs) data for 17 streamgages with drainage areas less than 50 square miles within the Des Moines Lobe landform region in north-central Iowa. Each DEM was hydrologically enforced and the five stream initiation methods were used to define channel initiation points and the downstream flow paths. The five different methods to define stream initiation were tested side-by-side for three watershed delineations: (1) the total drainage-area delineation, (2) an effective drainage-area delineation of basins based on a 2-percent annual exceedance probability (AEP) 12-hour rainfall, and (3) an effective drainage-area delineation based on a 20-percent AEP 12-hour rainfall.Generalized least squares regression analysis was used to develop a set of equations for sites in the Des Moines Lobe landform region for estimating discharges for ungaged stream sites with 50-, 20-, 10-, 4-, 2-, 1-, 0.5-, and 0.2-percent AEPs. A total of 17 streamgages were included in the development of the regression equations. In addition, geographic information system software was used to measure 58 selected basin-characteristics for each streamgage.Results of the regression analyses of the 15 lidar datasets indicate that the datasets that produce regional regression equations (RREs) with the best overall predictive accuracy are the National Hydrographic Dataset, Iowa Department of Natural Resources, and profile curvature of 0.5 stream initiation methods combined with the 20-percent AEP 12-hour rainfall watershed delineation method. These RREs have a mean average standard error of prediction (SEP) for 4-, 2-, and 1-percent AEP discharges of 53.9 percent and a mean SEP for all eight AEPs of 55.5 percent. Compared to the RREs developed in this study using the basin characteristics from the U.S. Geological Survey StreamStats application, the lidar basin characteristics provide better overall predictive accuracy.

Drainage Behavior in Soap Films Above and Below the CMC

NASA Astrophysics Data System (ADS)

Berg, S.; Adelizzi, E. A.; Troian, S. M.

2003-11-01

We investigate through laser interferometry the drainage behavior of Newtonian soap films initially entrained on a fiber frame at small and constant capillary number. The initial film thickness is sufficiently small that gravitational drainage is presumed minimal. The drainage of rigid soap films by capillary forces alone should proceed according to h(t) ˜ t^- 1/2. Our experimental results show much more rapid drainage with exponents as large as -2, especially for those solutions whose surfactant concentrations are below the CMC. Video recordings of the entire film surface reveal a variety of structures during the drainage process, some attributable to marginal regeneration. Though still a controversial issue, this regeneration process is believed to be caused by surfactant accumulation in the meniscus region (1). We show that modification of the relevant capillary drainage equation to account for Marangoni effects through a course-grained slip condition at the air-liquid interface produces exponents in better agreement with experimental findings. (1) V. A. Nierstrasz and G. Frens, JCIS 215, 28 (1999).

Effect of Drainage and Management Practices on Hydrology of Pine Plantation

Treesearch

R. Wayne Skaggs; Devendra M. Amatya; G. M. Chescheir; C. D. Blanton; J. W. Gilliam

2006-01-01

This paper reviews results of long-term studies, initiated in the late 1980s, to determine the hydrologic and water quality impacts of drainage and related water and forest management practices on a poorly drained site in Carteret County, North Carolina. Three watersheds, each approximately 25 ha, were instrumented to measure and record drainage rate, water table depth...

Effects of lumbar drainage on CSF dynamics in subarachnoid hemorrhage condition: A computational study.

PubMed

Abolfazli, Ehsan; Fatouraee, Nasser; Seddighi, Amir Saeed

2016-10-01

Lumbar drainage is considered a therapeutic measure in treatment of subarachnoid hemorrhage. However, the evidence on the effectiveness of this method is still inconclusive. In this study, a subject-specific three dimensional model of the cerebrospinal fluid (CSF) pathways and compartments was developed. The ventricular and the cranial and spinal subarachnoid spaces were reconstructed using magnetic resonance images. Occurrence of subarachnoid hemorrhage was modeled. Since the presence of blood in the CSF spaces is known to be the cause of complications such as cerebral vasospasm, concentration of blood in these spaces was investigated. Two cases of lumbar drains that were different in the drainage rate were studied. Temporal variations of concentration of blood in CSF spaces were calculated. It was observed that lumbar drainage accelerates the clearance of blood and, thereby, the spasmogens present in the cranial and spinal subarachnoid space. Higher clearance rates were observed at higher drainage rates. Copyright © 2016 Elsevier Ltd. All rights reserved.

Management of chest drainage tubes after lung surgery.

PubMed

Satoh, Yukitoshi

2016-06-01

Since chest tubes have been routinely used to drain the pleural space, particularly after lung surgery, the management of chest tubes is considered to be essential for the thoracic surgeon. The pleural drainage system requires effective drainage, suction, and water-sealing. Another key point of chest tube management is that a water seal is considered to be superior to suction for most air leaks. Nowadays, the most common pleural drainage device attached to the chest tube is the three-bottle system. An electronic chest drainage system has been developed that is effective in standardizing the postoperative management of chest tubes. More liberal use of digital drainage devices in the postoperative management of the pleural space is warranted. The removal of chest tubes is a common procedure occurring almost daily in hospitals throughout the world. Extraction of the tube is usually done at the end of full inspiration or at the end of full expiration. The tube removal technique is not as important as how it is done and the preparation for the procedure. The management of chest tubes must be based on careful observation, the patient's characteristics, and the operative procedures that had been performed.

A dynamic model of soil salinity and drainage generation in irrigated agriculture: A framework for policy analysis

NASA Astrophysics Data System (ADS)

Dinar, Ariel; Aillery, Marcel P.; Moore, Michael R.

1993-06-01

This paper presents a dynamic model of irrigated agriculture that accounts for drainage generation and salinity accumulation. Critical model relationships involving crop production, soil salinity, and irrigation drainage are based on newly estimated functions derived from lysimeter field tests. The model allocates land and water inputs over time based on an intertemporal profit maximization objective function and soil salinity accumulation process. The model is applied to conditions in the San Joaquin Valley of California, where environmental degradation from irrigation drainage has become a policy issue. Findings indicate that in the absence of regulation, drainage volumes increase over time before reaching a steady state as increased quantities of water are allocated to leaching soil salts. The model is used to evaluate alternative drainage abatement scenarios involving drainage quotas and taxes, water supply quotas and taxes, and irrigation technology subsidies. In our example, direct drainage policies are more cost-effective in reducing drainage than policies operating indirectly through surface water use, although differences in cost efficiency are relatively small. In some cases, efforts to control drainage may result in increased soil salinity accumulation, with implications for long-term cropland productivity. While policy adjustments may alter the direction and duration of convergence to a steady state, findings suggest that a dynamic model specification may not be necessary due to rapid convergence to a comon steady state under selected scenarios.

Effects of manual lymph drainage on cardiac autonomic tone in healthy subjects.

PubMed

Kim, Sung-Joong; Kwon, Oh-Yun; Yi, Chung-Hwi

2009-01-01

This study was designed to investigate the effects of manual lymph drainage on the cardiac autonomic tone. Thirty-two healthy male subjects were randomly assigned to manual lymph drainage (MLD) (experimental) and rest (control) groups. Electrocardiogram (ECG) parameters were recorded with bipolar electrocardiography using standard limb lead positions. The pressure-pain threshold (PPT) was quantitatively measured using an algometer. Heart rate variability differed significantly between the experimental and control groups (p < 0.05), but the PPT in the upper trapezius muscle did not (p > 0.05). These findings indicate that the application of MLD was effective in reducing the activity of the sympathetic nervous system.

Scleral electrocautery and its effects on choroid vessels: implications for subretinal fluid drainage during scleral buckling surgery.

PubMed

Roybal, C Nathaniel; Tsui, Irena; Sanfilippo, Christian; Hubschman, Jean-Pierre

2013-01-01

External drainage of subretinal fluid as part of a scleral buckling procedure rapidly restores the retinal pigment epithelium-neural retina interface in rhegmatogenous retinal detachments but carries the inherent risk of subretinal hemorrhage and retinal incarceration. The authors investigated variations to the technique to reduce the chance of subretinal hemorrhage originating from the choroid. A novel method for needle drainage using electrocautery of the sclerochoroidal layers before puncture was employed. The effect of 0% to 50% scleral electrocautery in a porcine model was investigated. A significant decrease in choroidal vessel diameter and choroidal vessel density at 40% electrocautery was demonstrated. Electrocautery without scleral cut-down before external drainage of subretinal fluid likely decreases the chance of subretinal hemorrhage by decreasing choroidal vascularity. Copyright 2013, SLACK Incorporated.

[Eye-associated lymphoid tissue (EALT) is continuously spread throughout the ocular surface from the lacrimal gland to the lacrimal drainage system].

PubMed

Knop, E; Knop, N

2003-11-01

Components of the mucosal immune system (MALT) have been identified in the conjunctiva (as CALT) and the lacrimal drainage system (as LDALT). Their structural and functional relation with the established immune protection by the lacrimal gland is unclear. Macroscopically normal and complete tissues of the conjunctiva, lacrimal drainage system and lacrimal gland from human body donors were investigated by analysis of translucent whole mounts, and using histology, immunohistology as well as scanning and transmission electron microscopy. A typical diffuse lymphoid tissue, composed of effector cells of the immune system (T-lymphocytes and IgA producing plasma cells) under an epithelium that contains the IgA transporter SC, is not isolated in the conjunctiva and lacrimal drainage system. It is anatomically continuous from the lacrimal gland along its excretory ducts into the conjunctiva and from there via the lacrimal canaliculi into the lacrimal drainage system. Lymphoid follicles occur in a majority (about 60%) and with bilateral symmetry. The topography of CALT corresponds to the position of the cornea in the closed eye. These results show that the MALT of the lacrimal gland, conjunctiva and lacrimal drainage system constitute an anatomical and functional unit for immune protection of the ocular surface. Therefore it should be integrated as an "eye-associated lymphoid tissue" (EALT) into the MALT system of the body. EALT can detect ocular surface antigens by the lymphoid follicles and can supply other organs and the ocular surface including the lacrimal gland with specific effector cells via the regulated recirculation of lymphoid cells.

Links Between Acceleration, Melting, and Supraglacial Lake Drainage of the Western Greenland Ice Sheet

NASA Technical Reports Server (NTRS)

Hoffman, M. J.; Catania, G. A.; Newmann, T. A.; Andrews, L. C.; Rumrill, J. A.

2012-01-01

The impact of increasing summer melt on the dynamics and stability of the Greenland Ice Sheet is not fully understood. Mounting evidence suggests seasonal evolution of subglacial drainage mitigates or counteracts the ability of surface runoff to increase basal sliding. Here, we compare subdaily ice velocity and uplift derived from nine Global Positioning System stations in the upper ablation zone in west Greenland to surface melt and supraglacial lake drainage during summer 2007. Starting around day 173, we observe speedups of 6-41% above spring velocity lasting approximately 40 days accompanied by sustained surface uplift at most stations, followed by a late summer slowdown. After initial speedup, we see a spatially uniform velocity response across the ablation zone and strong diurnal velocity variations during periods of melting. Most lake drainages were undetectable in the velocity record, and those that were detected only perturbed velocities for approximately 1 day, suggesting preexisting drainage systems could efficiently drain large volumes of water. The dynamic response to melt forcing appears to 1) be driven by changes in subglacial storage of water that is delivered in diurnal and episodic pulses, and 2) decrease over the course of the summer, presumably as the subglacial drainage system evolves to greater efficiency. The relationship between hydrology and ice dynamics observed is similar to that observed on mountain glaciers, suggesting that seasonally large water pressures under the ice sheet largely compensate for the greater ice thickness considered here. Thus, increases in summer melting may not guarantee faster seasonal ice flow.

Links Between Acceleration, Melting, and Supraglacial Lake Drainage of the Western Greenland Ice Sheet

NASA Technical Reports Server (NTRS)

Hoffman, M. J.; Catania, G. A.; Neumann, T. A.; Andrews, L. C.; Rumrill, J. A.

2011-01-01

The impact of increasing summer melt on the dynamics and stability of the Greenland Ice Sheet is not fully understood. Mounting evidence suggests seasonal evolution of subglacial drainage mitigates or counteracts the ability of surface runoff to increase basal sliding. Here, we compare subdaily ice velocity and uplift derived from nine Global Positioning System stations in the upper ablation zone in west Greenland to surface melt and supraglacial lake drainage during summer 2007. Starting around day 173, we observe speedups of 6-41% above spring velocity lasting 40 days accompanied by sustained surface uplift at most stations, followed by a late summer slowdown. After initial speedup, we see a spatially uniform velocity response across the ablation zone and strong diurnal velocity variations during periods of melting. Most lake drainages were undetectable in the velocity record, and those that were detected only perturbed velocities for approx 1 day, suggesting preexisting drainage systems could efficiently drain large volumes of water. The dynamic response to melt forcing appears to (1) be driven by changes in subglacial storage of water that is delivered in diurnal and episodic pulses, and (2) decrease over the course of the summer, presumably as the subglacial drainage system evolves to greater efficiency. The relationship between hydrology and ice dynamics observed is similar to that observed on mountain glaciers, suggesting that seasonally large water pressures under the ice sheet largely compensate for the greater ice thickness considered here. Thus, increases in summer melting may not guarantee faster seasonal ice flow.

Pesticide leaching via subsurface drains in different hydrologic situations

NASA Astrophysics Data System (ADS)

Zajíček, Antonín; Fučík, Petr; Liška, Marek; Dobiáš, Jakub

2017-04-01

esticides and their degradates in tile drainage waters were studied in two small, predominantly agricultural, tile-drained subcatchments in the Bohemian-Moravian Highlands, Czech Republic. The goal was to evaluate their occurence and the dymamics of their concentrations in drainage waters in different hydrologic situations using discharge and concentration monitoring together with 18O and 2H isotope analysis for Mean Residence Time (MRT) estimation and hydrograph separations during rainfall - runoff (R-R) events. The drainage and stream discharges were measured continuously at the closing outlets of three drainage groups and one small stream. During periods of prevailing base and interflow, samples were collected manually in two-week intervals for isotope analysis and during the spraying period (March to October) also for pesticide analysis. During R-R events, samples were taken by automatic samplers in intervals varying from 20 min (summer) to 1 hour (winter). To enable isotopic analysis, precipitation was sampled both manually at two-week intervals and also using an automatic rainfall sampler which collected samples of precipitation during the R-R events at 20-min. intervals. The isotopic analysis showed, that MRT of drainage base flow and interflow varies from 2,2 to 3,3 years, while MRT of base flow and interflow in surface stream is several months. During R-R events, the proportion of event water varied from 0 to 60 % in both drainage and surface runoff. The occurrence of pesticides and their degradates in drainage waters is strongly dependent on the hydrologic situation. While degradates were permanently present in drainage waters in high but varying concentrations according to instantaneous runoff composition, parent matters were detected almost exclusively during R-R events. In periods with prevailing base flow and interflow (grab samples), especially ESA forms of chloracetanilide degradates occured in high concentrations in all samples. Average sum of degradates varried between 1 730 - 5 760 ng/l. During R-R events, pesticide concentration varried according to runoff composition and time between sprayng and event. Event with no protortiom of event water in drainage runoff were typical by incereas in degradates concentrations (up to 20 000ng/l) and none or low occurence of parent matters. Events with significant event water proportion in drainage runoff were characterised by decrease in degradates concentrations and (when event happened soon affter spraying) by presence of paternal pesticides in drinage runoff. Instanteous concentrations of paren matters can be extremely high in that causes, up to 23 000 ng/l in drainage waters and up to 40 000 ng/l in small stream. Above results suggest that drainage systems could act as significant source of pesticide leaching. When parent compounds leaches via tile drainage systems, there are some border conditions that must exist together such as the occurence of R-R event soon after the pests application and the presence of event water (or water with short residence time in the catchment) in the drainage runoff.

Is the recurrence rate of chronic subdural hematomas dependent on the duration of drainage?

PubMed

Kale, Aydemir; Öz, İbrahim İlker; Gün, Eren Görkem; Kalaycı, Murat; Gül, Şanser

2017-05-01

Chronic subdural hematoma (CSDH) is the most frequent type of intracranial hemorrhage which especially affects the elderly. Various surgical techniques have been reported for CSDH treatment; optimal treatment methods are still controversial. In this study, the effects of long drainage durations on results and recurrences were investigated in patients on whom closed system drainage with burr hole craniotomy was applied due to CSDH. 90 patients with 105 CSDH were operated between 2008 and 2016. Patients were divided into two groups based on the duration of drainage. Group A (n = 40) was determined as 2-4 days of closed-system drainage, while Group B (n = 50) was recorded as 5-7 days of closed-system drainage. Recurrence was defined as accumulation of blood in the operation area and recurrence of symptoms within the monitoring period of six months. Recurrence was observed in 7 (15.6) of the Group A patients and 2 (3.3%) of the Group B patients. There was a statistically significant difference between groups in terms of recurrence rate (p = 0.04). Postoperative thickness of hematoma was measured in the first month follow-up computerized tomography. There was a statistically significant difference between groups in terms of postoperative thickness of residual hematoma (p = 0.05). 2-4 days of closed system drainage following burr hole craniotomy is an effective and reliable choice of treatment in CSDH. Nevertheless, increasing the duration of drainage to 5-7 days provided better results without increasing the risk of complication.

Evidence-based Value of Prophylactic Drainage in Gastrointestinal Surgery

PubMed Central

Petrowsky, Henrik; Demartines, Nicolas; Rousson, Valentin; Clavien, Pierre-Alain

2004-01-01

Objective: To determine the evidence-based value of prophylactic drainage in gastrointestinal (GI) surgery. Methods: An electronic search of the Medline database from 1966 to 2004 was performed to identify articles comparing prophylactic drainage with no drainage in GI surgery. The studies were reviewed and classified according to their quality of evidence using the grading system proposed by the Oxford Centre for Evidence-based Medicine. Seventeen randomized controlled trials (RCTs) were found for hepato-pancreatico-biliary surgery, none for upper GI tract, and 13 for lower GI tract surgery. If sufficient RCTs were identified, we performed a meta-analysis to characterize the drain effect using the random-effects model. Results: There is evidence of level 1a that drains do not reduce complications after hepatic, colonic, or rectal resection with primary anastomosis and appendectomy for any stage of appendicitis. Drains were even harmful after hepatic resection in chronic liver disease and appendectomy. In the absence of RCTs, there is a consensus (evidence level 5) about the necessity of prophylactic drainage after esophageal resection and total gastrectomy due to the potential fatal outcome in case of anastomotic and gastric leakage. Conclusion: Many GI operations can be performed safely without prophylactic drainage. Drains should be omitted after hepatic, colonic, or rectal resection with primary anastomosis and appendectomy for any stage of appendicitis (recommendation grade A), whereas prophylactic drainage remains indicated after esophageal resection and total gastrectomy (recommendation grade D). For many other GI procedures, especially involving the upper GI tract, there is a further demand for well-designed RCTs to clarify the value of prophylactic drainage. PMID:15570212

Suction forces generated by passive bile bag drainage on a model of post-subdural hematoma evacuation.

PubMed

Tenny, Steven O; Thorell, William E

2018-05-05

Passive drainage systems are commonly used after subdural hematoma evacuation but there is a dearth of published data regarding the suction forces created. We set out to quantify the suction forces generated by a passive drainage system. We created a model of passive drainage after subdural hematoma evacuation. We measured the maximum suction force generated with a bile bag drain for both empty drain tubing and fluid-filled drain tube causing a siphoning effect. We took measurements at varying heights of the bile bag to analyze if bile bag height changed suction forces generated. An empty bile bag with no fluid in the drainage tube connected to a rigid, fluid-filled model creates minimal suction force of 0.9 mmHg (95% CI 0.64-1.16 mmHg). When fluid fills the drain tubing, a siphoning effect is created and can generate suction forces ranging from 18.7 to 30.6 mmHg depending on the relative position of the bile bag and filled amount of the bile bag. The suction forces generated are statistically different if the bile bag is 50 cm below, level with or 50 cm above the experimental model. Passive bile bag drainage does not generate significant suction on a fluid-filled rigid model if the drain tubing is empty. If fluid fills the drain tubing then siphoning occurs and can increase the suction force of a passive bile bag drainage system to levels comparable to partially filled Jackson-Pratt bulb drainage.

The Effect of a Yield Stress on the Drainage of the Thin Film Between Two Colliding Newtonian Drops

NASA Astrophysics Data System (ADS)

Goel, Sachin; Ramachandran, Arun

2016-11-01

Coalescence of drops immersed in fluids possessing a yield stress has been of interest to many industries such as the oil extraction, cosmetics and food industries. Unfortunately, a theoretical understanding of the drainage of the thin film of Bingham fluid (a model yield stress fluid) that develops between two drops undergoing a collision is still lacking, with the exception of two prior studies that make ad-hoc assumptions about the film shape. In this work, we examine this problem via a combination of scaling analysis and numerical simulations based on the lubrication analysis. There are four key features of the film drainage process of Bingham fluids. First, the introduction of a yield stress in the suspending fluid retards the drainage process relative to Newtonian fluid of the same viscosity. Second, the drainage time shows a minimum with respect to the capillary number. Third, the effect of yield stress on the drainage process becomes more pronounced at higher capillary numbers and lower Hamaker constant. Lastly, below a critical height, drainage can be arrested completely due to the yield stress. This critical height scales as τ02R3 τ02R3 γ2 γ2 , where τ0 is the yield stress, R is the drop radius and γ is the interfacial tension, and is, surprisingly, independent of the force colliding the drops. This and other distinguishing characteristics of the drainage process will be elucidated in the presentation.

Influence of the stopcock on the efficiency of percutaneous drainage catheters: laboratory evaluation.

PubMed

D'Agostino, H B; Park, Y; Moyers, J P; vanSonnenberg, E; Sanchez, R B; Goodacre, B W; Kim, Y H; Vieira, M V

1992-08-01

The effects of stopcocks on percutaneous fluid drainage were tested in a laboratory model by using a standard stopcock (6-French inner diameter) and a prototype stopcock (9-French inner diameter) connected to 8-, 10-, 12-, 14-, and 16-French catheters. Catheters were immersed in water alone or in viscous fluid with particulate matter, and the system was connected to low wall suction or gravity drainage. The average volume of fluid aspirated in a given period with and without a stopcock was compared for each catheter. The standard stopcock decreased drainage efficiency for these catheters by 13-42%. This decreased drainage efficiency was worse with the larger catheters. Particulate fluid blocked the stopcock connection for all catheters. With the prototype stopcock, drainage of water alone was reduced by 0-9% for the catheters of different sizes. Particulate fluid did not obstruct the prototype stopcock with any size catheter. With gravity drainage, the volume of water aspirated was reduced by 12-42% with the standard stopcock and by 3-6% with the prototype stopcock. These data suggest that stopcock connections greatly influence the efficiency of the percutaneous drainage systems. Stopcocks with larger inner diameters may improve drainage over that achievable with the stopcocks that are currently available.

Modulation of gut barrier function in patients with obstructive jaundice using probiotic LP299v.

PubMed

Jones, Claire; Badger, Stephen A; Regan, Mark; Clements, Barry W; Diamond, Tom; Parks, Rowan W; Taylor, Mark A

2013-12-01

This study aimed to determine the effect of LP229v on intestinal permeability and tumour necrosis factor (TNF) p55 receptor concentrations in patients with obstructive jaundice undergoing biliary drainage. Patients undergoing biliary drainage were recruited and randomized into three groups to receive Lactobacillus plantarum 299v (LP299v), inactivated LP299v (placebo) or water. These were administered daily at noon until 7 days after biliary drainage. Intestinal permeability was measured using the lactulose/mannitol (L/M) dual sugar absorption test on admission, the day before biliary drainage and on days 1 and 7 after biliary drainage. Blood and urine were collected to determine the L/M ratio and the TNF p55 receptor levels at each time point. A total of 25 patients were recruited; 12 had choledocholithiasis and nine had a periampullary tumour. Open surgical biliary drainage was performed in nine patients, endoscopic retrograde cholangiopancreatography in 12 and percutaneous transhepatic cholangiography in two. Five patients received LP299v, five received placebo and seven, water. The median L/M ratio was 0.035 (0.018-0.065) at baseline. No difference existed between the groups on admission, before drainage and on day 7 after drainage (P=0.59, 0.175 and 0.61, respectively). The L/M ratio was lower in the LP299v group on day 1 after drainage [0.01 (0.01) vs. 0.18 (0.03-0.3) and 0.11 (0.07-0.14); P=0.37]. Although the TNF p55 receptor levels were lower on day 1 after drainage in the LP299v group (15.3 vs. 30.9 vs. 82.7 ng/ml; P=0.43), the concentration at the four time points was similar (P=0.24, 0.96, 0.43 and 0.68). Pretreatment with probiotic LP299v improves intestinal permeability after biliary drainage and attenuates the inflammatory response. However, a larger multicentre trial is required to determine the effect on clinical outcome.

[VC and DCE in groundwater and drainage channel water].

PubMed

Ackermann, A

2004-12-01

In an area used merely for gardening in a downland moor, which is partly transformed to an industrial estate, accidentally a contamination of a drainage channel with VOC's - predominantly chloroethylene (vinyl chloride [VC]) and 1.2-cis-dichloroethylene (DCE) - was found. The ascending ground water leaks into the drainage channels. The dissolved harmful substances (water solubility of VC is 1.6 g/l) can reach the radix range of plants and fruit bosks and can theoretically be incorporated with the water influx. Additionally the water from the drainage channels can be used to water the crops. Six gardens and a housing were involved. In the groundwater of the mainly concerned region max. 5,000 microg/l VOC's (quite predominantly VC and DCE) was measured from 147 samples. In the drainage channel water max. 2,500 microg/l was measured from 52 samples (limit value according to the drinking water ordinance is 10 microg/l). In the sediment of the channel with approximately 60,000 microg/kg VOC was found in dry matter (6 samples). We describe, how the consumer protection dept. dealt with this unexpected situation and what measures were taken. The impact on human health by the contaminated ground and channel water or by means of contaminated plants are determined for tree fruits, potatoes, bulbs and carrots. The soil air was contaminated, but in buildings no harmful compounds were detectioned.

Impacts of climate change on rainfall extremes and urban drainage systems: a review.

PubMed

Arnbjerg-Nielsen, K; Willems, P; Olsson, J; Beecham, S; Pathirana, A; Bülow Gregersen, I; Madsen, H; Nguyen, V-T-V

2013-01-01

A review is made of current methods for assessing future changes in urban rainfall extremes and their effects on urban drainage systems, due to anthropogenic-induced climate change. The review concludes that in spite of significant advances there are still many limitations in our understanding of how to describe precipitation patterns in a changing climate in order to design and operate urban drainage infrastructure. Climate change may well be the driver that ensures that changes in urban drainage paradigms are identified and suitable solutions implemented. Design and optimization of urban drainage infrastructure considering climate change impacts and co-optimizing these with other objectives will become ever more important to keep our cities habitable into the future.

Trends in surface-water quality in Connecticut, 1969-88

USGS Publications Warehouse

Trench, E.C.

1996-01-01

Surface-water-quality data from selected monitoring stations in Connecticut were analyzed for trend, using the Seasonal Kendall test, for water years 1969-88, 1975-88, and 1981-88. The number of constituents and stations evaluated varied with the different time periods. The 39 monitoring stations included 26 freshwater streams with associated discharge data, 7 tidally affected streams, 4 harbor stations, and 2 surface impoundments. Flow-adjustment procedures were used where possible to minimize the effects of stream- flow variability on trend results. The drainage area of the monitoring stations includes approximately 5,000 mi2 covering the State of Connecticut and about 11,000 mi2 in upstream drainage areas outside of the State. Drainage basin size for the freshwater streams ranges from 4.1 mi2 to 9,660 mi2. Land uses in the drainage basins range from undeveloped forested areas to highly urbanized metropolitan areas. During the period covered by the trend study, the State's population has grown, suburban development has increased, agricultural land use has decreased, and wastewater-treatment practices have improved. Increases in specific conductance and in the concentrations of calcium, magnesium, chloride, sulfate, dissolved solids, and total solids were geographically widespread and numerous during water years 1975-88 and indicate a general increase statewide in dissolved constituents in streamflow, both in urbanized and less developed areas. The effects of increasing urbanization, including municipal and industrial wastewater, septic system leachate, nonpoint runoff, and atmospheric deposition of contaminants, are possible causes for these increases. Decreases in turbidity and in the concentrations of total phosphorus, total organic carbon, and fecal coliform bacteria were geographically widespread and numerous during 1975-88. This general decrease in suspended material and bacteria may be attributable to basic improvements in the treatment of municipal and industrial wastewater during the period of record. Decreasing concentrations of total phosphorus may also be related to decreases in agricultural land use and to a decline in the use of detergents containing phosphorus. Detected decreases in total organic carbon and turbidity may have been caused, in part, by changes in sampling or analytical methods. Increases in total nitrogen, total organic nitrogen, and total nitrite-plus- nitrate were geographically widespread and numerous during 1975-88 and appear to indicate effects from both point sources in urbanized basins and nonpoint sources in less developed basins. The number of stations with increasing concentrations of nitrogen constituents was much smaller during 1981-88 than during 1975-88. Decreases in total ammonia nitrogen were detected at 11 stations during 1981-88. Decreases in total ammonia, sometimes paired with increases in total nitrite-plus-nitrate, may result from improvements in wastewater treatment. Increases in the concentration of dissolved oxygen, or dissolved oxygen as a percent of saturation, were geographically widespread and numer ous during 1969-88 and 1975-88. Increases were less common during 1981-88. Increases in dissolved oxygen in urbanized basins may be related to major improvements in wastewater treatment during the 1970's and 1980's. The magnitude of the trends detected during 1969-88 may have been affected in part by a change, around 1974, in the model of the instrument used to measure dissolved oxygen in the field. Statewide increases in pH were detected during 1969-88, 1975-88, and 1981-88, in both urbanized and less developed basins. The widespread increases in pH were unexpected, given the relatively acidic quality of precipitation in the region during the study period. Only two decreases in pH were detected, both in relatively undeveloped basins. Increases in pH in urbanized areas may be related to decreasing concentrations of ammonia and to requirements for neutralization of municipa

Remote Sensing Monitoring of Changes in Soil Salinity: A Case Study in Inner Mongolia, China.

PubMed

Wu, Jingwei; Vincent, Bernard; Yang, Jinzhong; Bouarfa, Sami; Vidal, Alain

2008-11-07

This study used archived remote sensing images to depict the history of changes in soil salinity in the Hetao Irrigation District in Inner Mongolia, China, with the purpose of linking these changes with land and water management practices and to draw lessons for salinity control. Most data came from LANDSAT satellite images taken in 1973, 1977, 1988, 1991, 1996, 2001, and 2006. In these years salt-affected areas were detected using a normal supervised classification method. Corresponding cropped areas were detected from NVDI (Normalized Difference Vegetation Index) values using an unsupervised method. Field samples and agricultural statistics were used to estimate the accuracy of the classification. Historical data concerning irrigation/drainage and the groundwater table were used to analyze the relation between changes in soil salinity and land and water management practices. Results showed that: (1) the overall accuracy of remote sensing in detecting soil salinity was 90.2%, and in detecting cropped area, 98%; (2) the installation/innovation of the drainage system did help to control salinity; and (3) a low ratio of cropped land helped control salinity in the Hetao Irrigation District. These findings suggest that remote sensing is a useful tool to detect soil salinity and has potential in evaluating and improving land and water management practices.

The effect of sampling frequency on the accuracy of nitrogen load estimates from a drained loblolly pine plantation in eastern North Carolina

Treesearch

George M. Chescheir; François Birgand; Shiying Tian; Mohamed A. Youssef; Devendra M. Amatya

2010-01-01

Nutrient loading in drainage outflow is estimated from measured flows and nutrient concentrations in the drainage water. The loading function is ideally continuous, representing the product of continuously measured outflows and nutrient concentrations in drainage water. However, loading is often estimated as the product of continuously measured outflow and nutrient...

Nutrient concentrations and loads in the northeastern United States - Status and trends, 1975-2003

USGS Publications Warehouse

Trench, Elaine C. Todd; Moore, Richard B.; Ahearn, Elizabeth A.; Mullaney, John R.; Hickman, R. Edward; Schwarz, Gregory E.

2012-01-01

The U.S. Geological Survey (USGS) National Water-Quality Assessment Program (NAWQA) began regional studies in 2003 to synthesize information on nutrient concentrations, trends, stream loads, and sources. In the northeastern United States, a study area that extends from Maine to central Virginia, nutrient data were evaluated for 130 USGS water-quality monitoring stations. Nutrient data were analyzed for trends in flow-adjusted concentrations, modeled instream (non-flow-adjusted) concentrations, and stream loads for 32 stations with 22 to 29 years of water-quality and daily mean streamflow record during 1975-2003 (termed the long-term period), and for 46 stations during 1993-2003 (termed the recent period), by using a coupled statistical model of streamflow and water quality developed by the USGS. Recent trends in flow-adjusted concentrations of one or more nutrients also were analyzed for 90 stations by using Tobit regression. Annual stream nutrient loads were estimated, and annual nutrient yields were calculated, for 47 stations for the long-term and recent periods, and for 37 additional stations that did not have a complete streamflow and water-quality record for 1993-2003. Nutrient yield information was incorporated for 9 drainage basins evaluated in a national NAWQA study, for a total of 93 stations evaluated for nutrient yields. Long-term downward trends in flow-adjusted concentrations of total nitrogen and total phosphorus (18 and 19 of 32 stations, respectively) indicate regional improvements in nutrient-related water-quality conditions. Most of the recent trends detected for total phosphorus were upward (17 of 83 stations), indicating possible reversals to the long-term improvements. Concentrations of nutrients in many streams persist at levels that are likely to affect aquatic habitat adversely and promote freshwater or coastal eutrophication. Recent trends for modeled instream concentrations, and modeled reference concentrations, were evaluated relative to ecoregion-based nutrient criteria proposed by the U.S. Environmental Protection Agency. Instream concentrations of total nitrogen and total phosphorus persist at levels higher than proposed criteria at more than one-third and about one-half, respectively, of the 46 stations analyzed. Long-term trends in nutrient loads were primarily downward, with downward trends in total nitrogen and total phosphorus loads detected at 12 and 17 of 32 stations, respectively. Upward trends were rare, with one upward trend for total nitrogen loads and none for total phosphorus. Trends in loads of nitrite-plus-nitrate nitrogen included 7 upward and 8 downward trends among 32 stations. Downward trends in loads of ammonia nitrogen and total Kjeldahl nitrogen were detected at all six stations evaluated. Long-term downward trends detected in four of the five largest drainage basins evaluated include: total nitrogen loads for the Connecticut, Delaware, and James Rivers; total Kjeldahl nitrogen and ammonia nitrogen loads for the Susquehanna River; ammonia nitrogen and nitrite-plus-nitrate nitrogen loads for the James River; and total phosphorus loads for the Connecticut and Delaware Rivers. No trends in load were detected for the Potomac River. Nutrient yields were evaluated relative to the extent of land development in 93 drainage basins. The undeveloped land-use category included forested drainage basins with undeveloped land ranging from 75 to 100 percent of basin area. Median total nitrogen yields for the 27 undeveloped drainage basins evaluated, including 9 basins evaluated in a national NAWQA study, ranged from 290 to 4,800 pounds per square mile per year (lb/mi2/yr). Total nitrogen yields even in the most pristine drainage basins may be elevated relative to natural conditions, because of high rates of atmospheric deposition of nitrogen in parts of the northeastern United States. Median total phosphorus yields ranged from 12 to 330 lb/mi2/yr for the 26 undeveloped basins evaluated. The undeveloped category includes some large drainage basins with point-source discharges and small percentages of developed land; in these basins, streamflow from undeveloped headwater areas dilutes streamflow in more urbanized reaches, and dampens but does not eliminate the point-source "signal" of higher nutrient loads. Median total nitrogen yields generally do not exceed 1,700 lb/mi2/yr, and median total phosphorus yields generally do not exceed 100 lb/mi2/yr, in the drainage basins that are least affected by human land-use and waste-disposal practices. Agricultural and urban land use has increased nutrient yields substantially relative to undeveloped drainage basins. Median total nitrogen yields for 24 agricultural basins ranged from 1,700 to 26,000 lb/mi2/yr, and median total phosphorus yields ranged from 94 to 1,000 lb/mi2/yr. The maximum estimated total nitrogen and total phosphorus yields, 32,000 and 16,000 lb/mi2/yr, respectively, for all stations in the region were in small (less than 50 square miles (mi2)) agricultural drainage basins. Median total nitrogen yields ranged from 1,400 to 17,000 lb/mi2/yr in 26 urbanized drainage basins, and median total phosphorus yields ranged from 43 to 1,900 lb/mi2/yr. Urbanized drainage basins with the highest nutrient yields are generally small (less than 300 mi2) and are drained by streams that receive major point-source discharges. Instream nutrient loads were evaluated relative to loads from point-source discharges in four drainage basins: the Quinebaug River Basin in Connecticut, Massachusetts, and Rhode Island; the Raritan River Basin in New Jersey; the Patuxent River Basin in Maryland; and the James River Basin in Virginia. Long-term downward trends in nutrient loads, coupled with similar trends in flow-adjusted nutrient concentrations, indicate long-term reductions in the delivery of most nutrients to these streams. However, the absence of recent downward trends in load for most nutrients, coupled with instream concentrations that exceed proposed nutrient criteria in several of these waste-receiving streams, indicates that challenges remain in reducing delivery of nutrients to streams from point sources. During dry years, the total nutrient load from point sources in some of the drainage basins approached or equaled the nutrient load transported by the stream.

Endoscopic Gallbladder Drainage for Acute Cholecystitis

PubMed Central

Widmer, Jessica; Alvarez, Paloma; Sharaiha, Reem Z.; Gossain, Sonia; Kedia, Prashant; Sarkaria, Savreet; Sethi, Amrita; Turner, Brian G.; Millman, Jennifer; Lieberman, Michael; Nandakumar, Govind; Umrania, Hiren; Gaidhane, Monica

2015-01-01

Background/Aims Surgery is the mainstay of treatment for cholecystitis. However, gallbladder stenting (GBS) has shown promise in debilitated or high-risk patients. Endoscopic transpapillary GBS and endoscopic ultrasound-guided GBS (EUS-GBS) have been proposed as safe and effective modalities for gallbladder drainage. Methods Data from patients with cholecystitis were prospectively collected from August 2004 to May 2013 from two United States academic university hospitals and analyzed retrospectively. The following treatment algorithm was adopted. Endoscopic retrograde cholangiopancreatography (ERCP) with sphincterotomy and cystic duct stenting was initially attempted. If deemed feasible by the endoscopist, EUS-GBS was then pursued. Results During the study period, 139 patients underwent endoscopic gallbladder drainage. Among these, drainage was performed in 94 and 45 cases for benign and malignant indications, respectively. Successful endoscopic gallbladder drainage was defined as decompression of the gallbladder without incidence of cholecystitis, and was achieved with ERCP and cystic duct stenting in 117 of 128 cases (91%). Successful endoscopic gallbladder drainage was also achieved with EUS-guided gallbladder drainage using transmural stent placement in 11 of 11 cases (100%). Complications occurred in 11 cases (8%). Conclusions Endoscopic gallbladder drainage techniques are safe and efficacious methods for gallbladder decompression in non-surgical patients with comorbidities. PMID:26473125

Evaluation of Life Cycle Assessment (LCA) for Roadway Drainage Systems.

PubMed

Byrne, Diana M; Grabowski, Marta K; Benitez, Amy C B; Schmidt, Arthur R; Guest, Jeremy S

2017-08-15

Roadway drainage design has traditionally focused on cost-effectively managing water quantity; however, runoff carries pollutants, posing risks to the local environment and public health. Additionally, construction and maintenance incur costs and contribute to global environmental impacts. While life cycle assessment (LCA) can potentially capture local and global environmental impacts of roadway drainage and other stormwater systems, LCA methodology must be evaluated because stormwater systems differ from wastewater and drinking water systems to which LCA is more frequently applied. To this end, this research developed a comprehensive model linking roadway drainage design parameters to LCA and life cycle costing (LCC) under uncertainty. This framework was applied to 10 highway drainage projects to evaluate LCA methodological choices by characterizing environmental and economic impacts of drainage projects and individual components (basin, bioswale, culvert, grass swale, storm sewer, and pipe underdrain). The relative impacts of drainage components varied based on functional unit choice. LCA inventory cutoff criteria evaluation showed the potential for cost-based criteria, which performed better than mass-based criteria. Finally, the local aquatic benefits of grass swales and bioswales offset global environmental impacts for four impact categories, highlighting the need to explicitly consider local impacts (i.e., direct emissions) when evaluating drainage technologies.

LABORATORY EVALUATION OF ZERO-VALENT IRON TO TREAT GROUNDWATER IMPACTED BY ACID MINE DRAINAGE

EPA Science Inventory

The generation and release of acidic, metal-rich water from mine wastes continues to be an intractable environmental problem. Although the effects of acid mine drainage (AMD) are most evident in surface waters, there is an obvious need for developing cost-effective approaches fo...

Lower incidence of complications in endoscopic nasobiliary drainage for hilar cholangiocarcinoma.

PubMed

Kawakubo, Kazumichi; Kawakami, Hiroshi; Kuwatani, Masaki; Haba, Shin; Kudo, Taiki; Taya, Yoko A; Kawahata, Shuhei; Kubota, Yoshimasa; Kubo, Kimitoshi; Eto, Kazunori; Ehira, Nobuyuki; Yamato, Hiroaki; Onodera, Manabu; Sakamoto, Naoya

2016-05-10

To identify the most effective endoscopic biliary drainage technique for patients with hilar cholangiocarcinoma. In total, 118 patients with hilar cholangiocarcinoma underwent endoscopic management [endoscopic nasobiliary drainage (ENBD) or endoscopic biliary stenting] as a temporary drainage in our institution between 2009 and 2014. We retrospectively evaluated all complications from initial endoscopic drainage to surgery or palliative treatment. The risk factors for biliary reintervention, post-endoscopic retrograde cholangiopancreatography (post-ERCP) pancreatitis, and percutaneous transhepatic biliary drainage (PTBD) were also analyzed using patient- and procedure-related characteristics. The risk factors for bilateral drainage were examined in a subgroup analysis of patients who underwent initial unilateral drainage. In total, 137 complications were observed in 92 (78%) patients. Biliary reintervention was required in 83 (70%) patients. ENBD was significantly associated with a low risk of biliary reintervention [odds ratio (OR) = 0.26, 95%CI: 0.08-0.76, P = 0.012]. Post-ERCP pancreatitis was observed in 19 (16%) patients. An absence of endoscopic sphincterotomy was significantly associated with post-ERCP pancreatitis (OR = 3.46, 95%CI: 1.19-10.87, P = 0.023). PTBD was required in 16 (14%) patients, and Bismuth type III or IV cholangiocarcinoma was a significant risk factor (OR = 7.88, 95%CI: 1.33-155.0, P = 0.010). Of 102 patients with initial unilateral drainage, 49 (48%) required bilateral drainage. Endoscopic sphincterotomy (OR = 3.24, 95%CI: 1.27-8.78, P = 0.004) and Bismuth II, III, or IV cholangiocarcinoma (OR = 34.69, 95%CI: 4.88-736.7, P < 0.001) were significant risk factors for bilateral drainage. The endoscopic management of hilar cholangiocarcinoma is challenging. ENBD should be selected as a temporary drainage method because of its low risk of complications.

Unilobar Versus Bilobar Biliary Drainage: Effect on Quality of Life and Bilirubin Level Reduction

PubMed Central

Gamanagatti, Shivanand; Singh, Tejbir; Sharma, Raju; Srivastava, Deep N; Dash, Nihar Ranjan; Garg, Pramod Kumar

2016-01-01

Background: Percutaneous biliary drainage is an accepted palliative treatment for malignant biliary obstruction. Purpose: To assess the effect on quality of life (QOL) and bilirubin level reduction in patients with inoperable malignant biliary obstruction treated by unilobar or bilobar percutaneous transhepatic biliary drainage (PTBD). Materials and Methods: Over a period of 2 years, 49 patients (age range, 22–75 years) of inoperable malignant biliary obstruction were treated by PTBD. Technical and clinical success rates, QOL, patency rates, survival rates, and complications were recorded. Clinical success rates, QOL, and bilirubin reduction were compared in patients treated with complete (n = 21) versus partial (n = 28) liver parenchyma drainage. QOL before and 1 month after biliary drainage were analyzed retrospectively between these two groups. Results: Biliary drainage was successful in all 49 patients, with an overall significant reduction of the postintervention bilirubin levels (P < 0.001) resulting in overall clinical success rate of 89.97%. Clinical success rates were similar in patients treated with whole-liver drainage versus partial-liver drainage. Mean serum bilirubin level before PTBD was 19.85 mg/dl and after the procedure at 1 month was 6.02 mg/dl. The mean baseline functional score was 39.35, symptom scale score was 59.55, and global health score was 27.45. At 1 month, mean functional score was 61.25, symptom scale score was 36.0 4, and global health score was 56.33, with overall significant improvement in QOL (<0.001). There was a statistically significant difference in the improvement of the QOL scores (P = 0.002), among patients who achieved clinical success, compared with those patients who did not achieve clinical success at 1 month. We did not find any significant difference in the QOL scores in patients according to the amount of liver drained (unilateral or bilateral drainage), the type of internalization used (ring biliary or stent). Overall, minor and major complications rates were 14.3% and 8.1%, respectively. Conclusion: Percutaneous biliary drainage provides good palliation of malignant obstructive jaundice. Partial-liver drainage achieved results as good as those after complete liver drainage with significant improvements in QOL and reduction of the bilirubin level. PMID:26962281

Cold air drainage flows subsidize montane valley ecosystem productivity.

PubMed

Novick, Kimberly A; Oishi, A Christopher; Miniat, Chelcy Ford

2016-12-01

In mountainous areas, cold air drainage from high to low elevations has pronounced effects on local temperature, which is a critical driver of many ecosystem processes, including carbon uptake and storage. Here, we leverage new approaches for interpreting ecosystem carbon flux observations in complex terrain to quantify the links between macro-climate condition, drainage flows, local microclimate, and ecosystem carbon cycling in a southern Appalachian valley. Data from multiple long-running climate stations and multiple eddy covariance flux towers are combined with simple models for ecosystem carbon fluxes. We show that cold air drainage into the valley suppresses local temperature by several degrees at night and for several hours before and after sunset, leading to reductions in growing season respiration on the order of ~8%. As a result, we estimate that drainage flows increase growing season and annual net carbon uptake in the valley by >10% and >15%, respectively, via effects on microclimate that are not be adequately represented in regional- and global-scale terrestrial ecosystem models. Analyses driven by chamber-based estimates of soil and plant respiration reveal cold air drainage effects on ecosystem respiration are dominated by reductions to the respiration of aboveground biomass. We further show that cold air drainage proceeds more readily when cloud cover and humidity are low, resulting in the greatest enhancements to net carbon uptake in the valley under clear, cloud-free (i.e., drought-like) conditions. This is a counterintuitive result that is neither observed nor predicted outside of the valley, where nocturnal temperature and respiration increase during dry periods. This result should motivate efforts to explore how topographic flows may buffer eco-physiological processes from macroscale climate change. © 2016 John Wiley & Sons Ltd.

Four-dimensional computed tomography angiographic evaluation of cranial dural arteriovenous fistula before and after embolization.

PubMed

Tian, Bing; Xu, Bing; Lu, Jianping; Liu, Qi; Wang, Li; Wang, Minjie

2015-06-01

This study aimed to evaluate the usefulness of four-dimensional CTA before and after embolization treatment with ONYX-18 in eleven patients with cranial dural arteriovenous fistulas, and to compare the results with those of the reference standard DSA. Eleven patients with cranial dural arteriovenous fistulas detected on DSA underwent transarterial embolization with ONYX-18. Four-dimensional CTA was performed an average of 2 days before and 4 days after DSA. Four-dimensional CTA and DSA images were reviewed by two neuroradiologists for identification of feeding arteries and drainage veins and for determining treatment effects. Interobserver and intermodality agreement between four-dimensional CTA and DSA were assessed. Forty-two feeding arteries were identified for 14 fistulas in the 11 patients. Of these, 36 (85.71%) were detected on four-dimensional CTA. After transarterial embolization, one patient got partly embolized, and the fistulas in the remaining 10 patients were completely occluded. The interobserver agreement for four-dimensional CTA and intermodality agreement between four-dimensional CTA and DSA were excellent (κ=1) for shunt location, identification of drainage veins, and fistula occlusion after treatment. Four-dimensional CTA images are highly accurate when compared with DSA images both before and after transarterial embolization treatment. Four-dimensional CTA can be used for diagnosis as well as follow-up of cranial dural arteriovenous fistulas in clinical settings. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

The Role of Endoscopic Biliary Drainage without Sphincterotomy in Gallstone Patients with Cholangitis and Suspected Common Bile Duct Stones Not Detected by Cholangiogram or Intraductal Ultrasonography

PubMed Central

Goong, Hyeon Jeong; Moon, Jong Ho; Lee, Yun Nah; Choi, Hyun Jong; Choi, Seo-Youn; Choi, Moon Han; Kim, Min Jin; Lee, Tae Hoon; Park, Sang-Heum; Lee, Hae Kyung

2017-01-01

Background/Aims Treatment for cholangitis without common bile duct (CBD) stones has not been established in patients with gallstones. We investigated the usefulness of endoscopic biliary drainage (EBD) without endoscopic sphincterotomy (EST) in patients diagnosed with gallstones and cholangitis without CBD stones by endoscopic retrograde cholangiopancreatography (ERCP) and intraductal ultrasonography (IDUS). Methods EBD using 5F plastic stents without EST was performed prospectively in patients with gallstones and cholangitis if CBD stones were not diagnosed by ERCP and IDUS. After ERCP, all patients underwent laparoscopic cholecystectomy. The primary outcomes were clinical and technical success. The secondary outcomes were recurrence rate of biliary events and procedure-related adverse events. Results Among 187 patients with gallstones and cholangitis, 27 patients without CBD stones according to ERCP and IDUS received EBD using 5F plastic stents without EST. The stents were maintained in all patients until laparoscopic cholecystectomy, and recurrence of cholangitis was not observed. After cholecystectomy, the stents were removed spontaneously in 12 patients and endoscopically in 15 patients. Recurrence of CBD stones was not detected during the follow-up period (median, 421 days). Conclusions EBD using 5F plastic stents without EST may be safe and effective for the management of cholangitis accompanied by gallstones in patients without CBD stones according to ERCP and IDUS. PMID:28104896

Portal-endocrine and gastric-exocrine drainage technique of pancreas transplantation provides an easy access for evaluation of pancreatic allograft dysfunction: six-year experience at a single center.

PubMed

Zibari, Gazi B; Fallahzadeh, Mohammad Kazem; Hamidian Jahromi, Alireza; Zakhary, Joseph; Dies, David; Wellman, Greg; Singh, Neeraj; Shokouh-Amiri, Hosein

2014-01-01

The aim of this study is to report our six-year experience with portal-endocrine and gastric-exocrine drainage technique of pancreatic transplantation, which was first developed and implemented at our center in 2007. In this study, the outcomes of all patients at our center who had pancreas transplantation with portal-endocrine and gastric-exocrine drainage technique were evaluated. From October 2007 to November 2013, 38 patients had pancreas transplantation with this technique - 31 simultaneous kidney pancreas and seven pancreas alone. Median duration of follow-up was 3.8 years. One-, three-, and five-year patient and graft survival rates were 94%, 87%, 70% and 83%, 65%, 49%, respectively. For pancreas allograft dysfunction evaluation, 51 upper endoscopies were performed in 14 patients; donor duodenal biopsies were successfully obtained in 45 (88%). We detected nine episodes of acute rejection (eight patients) and seven episodes of cytomegalovirus (CMV) duodenitis (six patients). No patient developed any complication due to upper endoscopy. Portal-endocrine and gastric-exocrine drainage technique of pancreas transplantation provides lifelong easy access to the transplanted duodenum for evaluation of pancreatic allograft dysfunction.

Water-quality assessment of the Albemarle-Pamlico drainage basin, North Carolina and Virginia; trace elements in Asiatic clam (Corbicula fluminea) soft tissues and redbreast sunfish (Lepomis auritus) livers, 1992-93

USGS Publications Warehouse

Ruhl, P.M.; Smith, K.E.

1996-01-01

The analysis of potential contaminants in biological tissues is an important part of many water-quality assessment programs, including the National Water-Quality Assessment (NAWQA) Program. Tissue analyses often are used to provide information about (1) direct threats to ecosystem integrity, and (2) the occurrence and distribution of potential contaminants in the environment. During 1992-93, trace elements in Asiatic clam (Corbicula fluminea) soft tissues and redbreast sunfish (Lepomis auritus) livers were analyzed to obtain information about the occurrence and distribution of trace element contaminants in the Albemarle-Pamlico Drainage Basin of North Carolina and Virginia. The investigation was conducted as part of the NAWQA Program. All but 3 of the 22 trace elements that were analyzed were detected. Although all 10 of the U.S. Environmental Protection Agency (U.S. EPA) priority pollutants were detected in the tissues sampled, they were present in relatively low concentrations. Concentrations of U.S. EPA priority pollutants in Asiatic clams collected in the Albemarle-Pamlico Drainage Basin are similar to concentrations observed in other NAWQA study units in the southeastern United States. Mercury (a U.S. EPA priority pollutant) was widely detected, being present in 29 of 30 tissue samples, but concentrations did not exceed the FDA action level for mercury of a risk-based screening value for the general public. Mercury concentrations in Asiatic clams were similar to concentrations in other NAWQA study areas in the Southeast.

Experimental Investigation of Hysteretic Dynamic Capillarity Effect in Unsaturated Flow

PubMed Central

Zhuang, Luwen; Qin, Chao‐Zhong; de Waal, Arjen

2017-01-01

Abstract The difference between average pressures of two immiscible fluids is commonly assumed to be the same as macroscopic capillary pressure, which is considered to be a function of saturation only. However, under transient conditions, a dependence of this pressure difference on the time rate of saturation change has been observed by many researchers. This is commonly referred to as dynamic capillarity effect. As a first‐order approximation, the dynamic term is assumed to be linearly dependent on the time rate of change of saturation, through a material coefficient denoted by τ. In this study, a series of laboratory experiments were carried out to quantify the dynamic capillarity effect in an unsaturated sandy soil. Primary, main, and scanning drainage experiments, under both static and dynamic conditions, were performed on a sandy soil in a small cell. The value of the dynamic capillarity coefficient τ was calculated from the air‐water pressure differences and average saturation values during static and dynamic drainage experiments. We found a dependence of τ on saturation, which showed a similar trend for all drainage conditions. However, at any given saturation, the value of τ for primary drainage was larger than the value for main drainage and that was in turn larger than the value for scanning drainage. Each data set was fit a simple log‐linear equation, with different values of fitting parameters. This nonuniqueness of the relationship between τ and saturation and possible causes is discussed. PMID:29398729

Experimental Investigation of Hysteretic Dynamic Capillarity Effect in Unsaturated Flow

NASA Astrophysics Data System (ADS)

Zhuang, Luwen; Hassanizadeh, S. Majid; Qin, Chao-Zhong; de Waal, Arjen

2017-11-01

The difference between average pressures of two immiscible fluids is commonly assumed to be the same as macroscopic capillary pressure, which is considered to be a function of saturation only. However, under transient conditions, a dependence of this pressure difference on the time rate of saturation change has been observed by many researchers. This is commonly referred to as dynamic capillarity effect. As a first-order approximation, the dynamic term is assumed to be linearly dependent on the time rate of change of saturation, through a material coefficient denoted by τ. In this study, a series of laboratory experiments were carried out to quantify the dynamic capillarity effect in an unsaturated sandy soil. Primary, main, and scanning drainage experiments, under both static and dynamic conditions, were performed on a sandy soil in a small cell. The value of the dynamic capillarity coefficient τ was calculated from the air-water pressure differences and average saturation values during static and dynamic drainage experiments. We found a dependence of τ on saturation, which showed a similar trend for all drainage conditions. However, at any given saturation, the value of τ for primary drainage was larger than the value for main drainage and that was in turn larger than the value for scanning drainage. Each data set was fit a simple log-linear equation, with different values of fitting parameters. This nonuniqueness of the relationship between τ and saturation and possible causes is discussed.

Urban drainage system planning and design--challenges with climate change and urbanization: a review.

PubMed

Yazdanfar, Zeinab; Sharma, Ashok

2015-01-01

Urban drainage systems are in general failing in their functions mainly due to non-stationary climate and rapid urbanization. As these systems are becoming less efficient, issues such as sewer overflows and increase in urban flooding leading to surge in pollutant loads to receiving water bodies are becoming pervasive rapidly. A comprehensive investigation is required to understand these factors impacting the functioning of urban drainage, which vary spatially and temporally and are more complex when weaving together. It is necessary to establish a cost-effective, integrated planning and design framework for every local area by incorporating fit for purpose alternatives. Carefully selected adaptive measures are required for the provision of sustainable drainage systems to meet combined challenges of climate change and urbanization. This paper reviews challenges associated with urban drainage systems and explores limitations and potentials of different adaptation alternatives. It is hoped that the paper would provide drainage engineers, water planners, and decision makers with the state of the art information and technologies regarding adaptation options to increase drainage systems efficiency under changing climate and urbanization.

A new model for simulating spring discharge recession and estimating effective porosity of karst aquifers

NASA Astrophysics Data System (ADS)

Xu, Bin; Ye, Ming; Dong, Shuning; Dai, Zhenxue; Pei, Yongzhen

2018-07-01

Quantitative analysis of recession curves of karst spring hydrographs is a vital tool for understanding karst hydrology and inferring hydraulic properties of karst aquifers. This paper presents a new model for simulating karst spring recession curves. The new model has the following characteristics: (1) the model considers two separate but hydraulically connected reservoirs: matrix reservoir and conduit reservoir; (2) the model separates karst spring hydrograph recession into three stages: conduit-drainage stage, mixed-drainage stage (with both conduit drainage and matrix drainage), and matrix-drainage stage; and (3) in the mixed-drainage stage, the model uses multiple conduit layers to present different levels of conduit development. The new model outperforms the classical Mangin model and the recently developed Fiorillo model for simulating observed discharge at the Madison Blue Spring located in northern Florida. This is attributed to the latter two characteristics of the new model. Based on the new model, a method is developed for estimating effective porosity of the matrix and conduit reservoirs for the three drainage stages. The estimated porosity values are consistent with measured matrix porosity at the study site and with estimated conduit porosity reported in literature. The new model for simulating karst spring hydrograph recession is mathematically general, and can be applied to a wide range of karst spring hydrographs to understand groundwater flow in karst aquifers. The limitations of the model are discussed at the end of this paper.

The comparison of manual lymph drainage and ultrasound therapy on the leg swelling caused by wearing high heels.

PubMed

Lee, Dong-Yeop; Han, Ji-Su; Jang, Eun-Ji; Seo, Dong-Kwon; Hong, Ji-Heon; Lee, Sang-Sook; Lee, Dong-Geol; Yu Lee, Jae-Ho

2014-01-01

One of the major symptoms when women are wearing high heels for a long time is leg swelling. The purpose of this study was to compare the effect of manual lymph drainage with ultrasound therapy. The forty-five healthy women of twenties were participated in this study and divided randomly into three groups; manual lymph drainage group (n=15), ultrasound therapy group (n=15) and control group (n=15). Swelling was measured before wearing the high heels (10 cm-height), after one-hour of wearing the high heels, wearing the high heels of one-hour after the intervention of 15 minutes. Also swelling was calculated by using a tape measure, volumeter and body composition analyzer. Statistical analysis of the comparison between the three groups was performed by one-way ANOVA. Also comparison to the mean value in swelling according to the time was performed by repeated measure ANOVA. As the result of this study, a significant changes have emerged within each of manual lymph drainage, ultrasound therapy and control group (p< 0.05). However, there were no significant differences between each group (p> 0.05). But the mean value of manual lymph drainage group showed the tendency of fast recovering before causing swelling. Therefore, we consider that the clinical treatment of manual lymph drainage and ongoing studies will be made since manual lymph drainage is very effective in releasing the leg swelling caused by wearing high heels and standing for a long time at work.

An investigation into the use of road drainage structures by wildlife in Maryland.

DOT National Transportation Integrated Search

2011-08-01

The research team documented culvert use by 57 species of vertebrates with both infra-red motion detecting digital : game cameras and visual sightings. Species affiliations with culvert characteristics were analyzed using 2 : statistics, Canonical ...

Influence of drainage and nutrient-solution nitrogen and potassium concentrations on the agronomic behavior of bell-pepper plants cultivated in a substrate.

PubMed

Wamser, Anderson Fernando; Cecilio Filho, Arthur Bernardes; Nowaki, Rodrigo Hiyoshi Dalmazzo; Mendoza-Cortez, Juan Waldir; Urrestarazu, Miguel

2017-01-01

The interactive effects of N (6, 9, 12 and 15 mmol L-1) and K (3, 5, 7, and 9 mmol L-1) concentrations in nutrient solutions were evaluated on bell pepper grown in a coconut-coir substrate and fertilized without drainage. An additional treatment with drainage was evaluated using N and K concentrations of 12 and 7 mmol L-1, respectively. The hybrid Eppo cultivar of yellow bell pepper was cultivated for 252 days beginning 9 November 2012. Electrical conductivity (EC), the N and K concentrations in the substrate solution, marketable fruit yield, total dry weight and macronutrient concentrations in shoots were periodically evaluated. Fruit production was lower in the system without drainage, regardless of the N and K concentrations, compared to the recommended 10-20% drainage of the volume of nutrient solution applied. Higher K concentrations in the nutrient solution did not affect plant production in the system without drainage for the substrate with an initial K concentration of 331.3 mg L-1. Fruit yield was higher without drainage at a nutrient-solution N concentration of 10.7 mmol L-1. The upper EC limit of the substrate solution in the system without drainage was exceeded 181 days after planting. Either lower nutrient concentrations in the nutrient solution or a drainage system could thus control the EC in the substrate solution.

Water-quality monitoring and process understanding in support of environmental policy and management

USGS Publications Warehouse

Peters, N.E.

2008-01-01

The quantity and quality of freshwater at any point on the landscape reflect the combined effects of many processes operating along hydrological pathways within a drainage basin/watershed/catchment. Primary drivers for the availability of water are landscape changes and patterns, and the processes affecting the timing, magnitude, and intensity of precipitation, including global climate change. The degradation of air, land, and water in one part of a drainage basin can have negative effects on users downstream; the time and space scales of the effects are determined by the residence time along the various hydrological pathways. Hydrology affects transport, deposition, and recycling of inorganic materials and sediment. These components affect biota and associated ecosystem processes, which rely on sustainable flows throughout a drainage basin. Human activities on all spatial scales affect both water quantity and quality, and some human activities can have a disproportionate effect on an entire drainage basin. Aquatic systems have been continuously modified by agriculture, through land-use change, irrigation and navigation, disposal of urban, mining, and industrial wastes, and engineering modifications to the environment. Interdisciplinary integrated basin studies within the last several decades have provided a more comprehensive understanding of the linkages among air, land, and water resources. This understanding, coupled with environmental monitoring, has evolved a more multidisciplinary integrated approach to resource management, particularly within drainage basins.

Streamflow distribution maps for the Cannon River drainage basin, southeast Minnesota, and the St. Louis River drainage basin, northeast Minnesota

USGS Publications Warehouse

Smith, Erik A.; Sanocki, Chris A.; Lorenz, David L.; Jacobsen, Katrin E.

2017-12-27

Streamflow distribution maps for the Cannon River and St. Louis River drainage basins were developed by the U.S. Geological Survey, in cooperation with the Legislative-Citizen Commission on Minnesota Resources, to illustrate relative and cumulative streamflow distributions. The Cannon River was selected to provide baseline data to assess the effects of potential surficial sand mining, and the St. Louis River was selected to determine the effects of ongoing Mesabi Iron Range mining. Each drainage basin (Cannon, St. Louis) was subdivided into nested drainage basins: the Cannon River was subdivided into 152 nested drainage basins, and the St. Louis River was subdivided into 353 nested drainage basins. For each smaller drainage basin, the estimated volumes of groundwater discharge (as base flow) and surface runoff flowing into all surface-water features were displayed under the following conditions: (1) extreme low-flow conditions, comparable to an exceedance-probability quantile of 0.95; (2) low-flow conditions, comparable to an exceedance-probability quantile of 0.90; (3) a median condition, comparable to an exceedance-probability quantile of 0.50; and (4) a high-flow condition, comparable to an exceedance-probability quantile of 0.02.Streamflow distribution maps were developed using flow-duration curve exceedance-probability quantiles in conjunction with Soil-Water-Balance model outputs; both the flow-duration curve and Soil-Water-Balance models were built upon previously published U.S. Geological Survey reports. The selected streamflow distribution maps provide a proactive water management tool for State cooperators by illustrating flow rates during a range of hydraulic conditions. Furthermore, after the nested drainage basins are highlighted in terms of surface-water flows, the streamflows can be evaluated in the context of meeting specific ecological flows under different flow regimes and potentially assist with decisions regarding groundwater and surface-water appropriations. Presented streamflow distribution maps are foundational work intended to support the development of additional streamflow distribution maps that include statistical constraints on the selected flow conditions.

Meltwater drainage beneath ice sheets: What can we learn from uniting observations of paleo- and contemporary subglacial hydrology?

NASA Astrophysics Data System (ADS)

Simkins, L. M.; Carter, S. P.; Greenwood, S. L.; Schroeder, D. M.

2017-12-01

Understanding meltwater at the base of ice sheets is critical for predicting ice flow and subglacial sediment deformation. Whereas much progress has been made with observing contemporary systems, these efforts have been limited by the short temporal scales of remote sensing data, the restricted spatial coverage of radar sounding data, and the logistical challenges of direct access. Geophysical and sedimentological data from deglaciated continental shelves reveal broad spatial and temporal perspectives of subglacial hydrology, that complement observations of contemporary systems. Massive bedrock channels, such as those on the sediment-scoured inner continental shelf of the Amundsen Sea and the western Antarctic Peninsula, are up to hundreds of meters deep, which indicate either catastrophic drainage events or slower channel incision over numerous glaciations or sub-bank full drainage events. The presence of these deep channels has implications for further ice loss as they may provide conduits today for warm water incursion into sub-ice shelf cavities. Sediment-based subglacial channels, widespread in the northern hemisphere terrestrial domain and increasingly detected on both Arctic and Antarctic marine margins, help characterize more ephemeral drainage systems active during ice sheet retreat. Importantly, some observed sediment-based channels are connected to upstream subglacial lakes and terminate at paleo-grounding lines. From these records of paleo-subglacial hydrology, we extract the relative timing of meltwater drainage, estimate water fluxes, and contemplate the sources and ultimate fate of basal meltwater, refining predictive models for modern systems. These insights provided by geological data fill a gap in knowledge regarding spatial and temporal dynamics of subglacial hydrology and offer hindsight into meltwater drainage influence/association with ice flow and retreat behavior. The union of information gathered from paleo- and contemporary subglacial hydrology strengthens our understanding of the nature of meltwater drainage beneath ice sheets and informs better theory and numerical models.

Hepatic parenchymal atrophy induction for intractable segmental bile duct injury after liver resection.

PubMed

Hwang, Shin; Park, Gil-Chun; Ha, Tae-Yong; Ko, Gi-Young; Gwon, Dong-Il; Choi, Young-Il; Song, Gi-Won; Lee, Sung-Gyu

2012-05-01

Liver resection can result in various types of bile duct injuries but their treatment is usually difficult and often leads to intractable clinical course. We present an unusual case of hepatic segment III duct (B3) injury, which occurred after left medial sectionectomy for large hepatocellular carcinoma and was incidentally detected 1 week later due to bile leak. Since the pattern of this B3 injury was not adequate for operative biliary reconstruction, atrophy induction of the involved hepatic parenchyma was attempted. This treatment consisted of embolization of the segment III portal branch to inhibit bile production, induction of heavy adhesion at the bile leak site and clamping of the percutaneous transhepatic biliary drainage (PTBD) tube to accelerate segment III atrophy. This entire procedure, from liver resection to PTBD tube removal took 4 months. This patient has shown no other complication or tumor recurrence for 4 years to date. These findings suggest that percutaneous segmental portal vein embolization, followed by intentional clamping of external biliary drainage, can effectively control intractable bile leak from segmental bile duct injury.

Characteristic pattern of pleural effusion in electrical impedance tomography images of critically ill patients.

PubMed

Becher, T; Bußmeyer, M; Lautenschläger, I; Schädler, D; Weiler, N; Frerichs, I

2018-06-01

Electrical impedance tomography (EIT) is increasingly used for continuous monitoring of ventilation in intensive care patients. Clinical observations in patients with pleural effusion show an increase in out-of-phase impedance changes. We hypothesised that out-of-phase impedance changes are a typical EIT finding in patients with pleural effusion and could be useful in its detection. We conducted a prospective observational study in intensive care unit patients with and without pleural effusion. In patients with pleural effusion, EIT data were recorded before, during, and after unilateral drainage of pleural effusion. In patients with no pleural effusion, EIT data were recorded without any intervention. EIT images were separated into four quadrants of equal size. We analysed the sum of out-of-phase impedance changes in the affected quadrant in patients with pleural effusion before, during, and after drainage and compared it with the sum of out-of-phase impedance changes in the dorsal quadrants of patients without pleural effusion. We included 20 patients with pleural effusion and 10 patients without pleural effusion. The median sum of out-of-phase impedance changes was 70 (interquartile range 49-119) arbitrary units (a.u.) in patients with pleural effusion before drainage, 25 (12-46) a.u. after drainage (P<0.0001) and 11 (6-17) a.u. in patients without pleural effusion (P<0.0001 vs pleural effusion before drainage). The area under the receiver operating characteristics curve was 0.96 (95% limits of agreement 0.91-1.01) between patients with pleural effusion before drainage and those without pleural effusion. In patients monitored with EIT, the presence of out-of-phase impedance changes is highly suspicious of pleural effusion and should trigger further examination. Copyright © 2018 British Journal of Anaesthesia. Published by Elsevier Ltd. All rights reserved.

Relative importance of impervious area, drainage density, width function, and subsurface storm drainage on flood runoff from an urbanized catchment

NASA Astrophysics Data System (ADS)

Ogden, Fred L.; Raj Pradhan, Nawa; Downer, Charles W.; Zahner, Jon A.

2011-12-01

The literature contains contradictory conclusions regarding the relative effects of urbanization on peak flood flows due to increases in impervious area, drainage density and width function, and the addition of subsurface storm drains. We used data from an urbanized catchment, the 14.3 km2 Dead Run watershed near Baltimore, Maryland, USA, and the physics-based gridded surface/subsurface hydrologic analysis (GSSHA) model to examine the relative effect of each of these factors on flood peaks, runoff volumes, and runoff production efficiencies. GSSHA was used because the model explicitly includes the spatial variability of land-surface and hydrodynamic parameters, including subsurface storm drains. Results indicate that increases in drainage density, particularly increases in density from low values, produce significant increases in the flood peaks. For a fixed land-use and rainfall input, the flood magnitude approaches an upper limit regardless of the increase in the channel drainage density. Changes in imperviousness can have a significant effect on flood peaks for both moderately extreme and extreme storms. For an extreme rainfall event with a recurrence interval in excess of 100 years, imperviousness is relatively unimportant in terms of runoff efficiency and volume, but can affect the peak flow depending on rainfall rate. Changes to the width function affect flood peaks much more than runoff efficiency, primarily in the case of lower density drainage networks with less impermeable area. Storm drains increase flood peaks, but are overwhelmed during extreme rainfall events when they have a negligible effect. Runoff in urbanized watersheds with considerable impervious area shows a marked sensitivity to rainfall rate. This sensitivity explains some of the contradictory findings in the literature.

Nitrate concentration-drainage flow (C-Q) relationship for a drained agricultural field in Eastern North Carolina Plain

NASA Astrophysics Data System (ADS)

Liu, W.; Youssef, M.; Birgand, F.; Chescheir, G. M.; Maxwell, B.; Tian, S.

2017-12-01

Agricultural drainage is a practice used to artificially enhance drainage characteristics of naturally poorly drained soils via subsurface drain tubing or open-ditch systems. Approximately 25% of the U.S. agricultural land requires improved drainage for economic crop production. However, drainage increases the transport of dissolved agricultural chemicals, particularly nitrates to downstream surface waters. Nutrient export from artificially drained agricultural landscapes has been identified as the leading source of elevated nutrient levels in major surface water bodies in the U.S. Controlled drainage has long been practiced to reduce nitrogen export from agricultural fields to downstream receiving waters. It has been hypothesized that controlled drainage reduces nitrogen losses by promoting denitrification, reducing drainage outflow from the field, and increasing plant uptake. The documented performance of the practice was widely variable as it depends on several site-specific factors. The goal of this research was to utilize high frequency measurements to investigate the effect of agricultural drainage and related management practices on nitrate fate and transport for an artificially drained agricultural field in eastern North Carolina. We deployed a field spectrophotometer to measure nitrate concentration every 45 minutes and measured drainage flow rate using a V-notch weir every 15 minutes. Furthermore, we measured groundwater level, precipitation, irrigation amount, temperature to characterize antecedent conditions for each event. Nitrate concentration-drainage flow (C-Q) relationships generated from the high frequency measurements illustrated anti-clockwise hysteresis loops and nitrate flushing mechanism in response to most precipitation and irrigation events. Statistical evaluation will be carried out for the C-Q relationships. The results of our analysis, combined with numerical modeling, will provide a better understanding of hydrological and biogeochemical processes controlling the fate and transport of nitrate in drained agricultural landscapes.

Drainage alone or combined with anti-tumor therapy for treatment of obstructive jaundice caused by recurrence and metastasis after primary tumor resection.

PubMed

Xu, Chuan; Huang, Xin-En; Wang, Shu-Xiang; Lv, Peng-Hua; Sun, Ling; Wang, Fu-An; Wang, Li-Fu

2014-01-01

To compare drainage alone or combined with anti-tumor therapy for treatment of obstructive jaundice caused by recurrence and metastasis after primary tumor resection. We collect 42 patients with obstructive jaundice caused by recurrence and metastasis after tumor resection from January 2008 - August 2012, for which percutaneous transhepatic catheter drainage (pTCD)/ percutaneous transhepatic biliary stenting (pTBS) were performed. In 25 patients drainage was combined with anti-tumor treatment, antineoplastic therapy including intra/postprodure local treatment and postoperative systemic chemotherapy, the other 17 undergoing drainage only. We assessed the two kinds of treatment with regard to patient prognosis. Both treatments demonstrated good effects in reducing bilirubin levels in the short term and promoting liver function. The time to reobstruction was 125 days in the combined group and 89 days in the drainage only group; the mean survival times were 185 and 128 days, the differences being significant. Interventional drainage in the treatment of the obstructive jaundice caused by recurrence and metastasis after tumor resection can decrease bilirubin level quickly in a short term and promote the liver function recovery. Combined treatment prolongs the survival time and period before reobstruction as compared to drainage only.

External Versus Internal Pancreatic Duct Drainage for the Early Efficacy After Pancreaticoduodenectomy: A Retrospectively Comparative Study.

PubMed

Wang, Gang; Li, Le; Ma, Yuan; Qu, Feng-Zhi; Zhu, Hong; Lv, Jia-Chen; Jia, Yue-Hui; Wu, Lin-Feng; Sun, Bei

2016-08-01

To compare the early efficacy of external versus internal pancreatic duct drainage after pancreaticoduodenectomy (PD), providing clinical evidence for selecting the optimal approach to pancreatic duct drainage. The clinical data of 395 consecutive patients undergoing PD from 2006 to 2013 were analyzed retrospectively. All the patients were divided into external and internal drainage group. Intraoperative blood loss, surgery duration, postoperative hospitalization duration, mortality rate, PF, and other complications were compared between the two groups. The perioperative relative risk factors that might induce PF were analyzed. External drainage significantly reduced the incidences of post-PD PF, delayed gastric emptying, abdominal infection, bowel obstruction, overall complications, and shortened the healing time of PF (p < .05). The univariate analysis showed that the pancreatic duct drainage method, body mass index (BMI), preoperative serum bilirubin level, perioperative blood transfusion, pancreaticojejunostomy approach, pancreatic texture, pancreatic duct diameter, and primary disease differed markedly between the two groups (p < .05). A multivariate analysis revealed that BMI ≥ 25 kg/m(2), internal pancreatic duct drainage, pancreatic duct diameter <3 mm, soft pancreatic texture, and ampullary disease were independent risk factors for PF. External pancreatic duct drainage can effectively reduce the morbidity of PF and overall complications after PD.

A single-centre experience of Roux-en-Y enteric drainage for pancreas transplantation.

PubMed

Amin, Irum; Butler, Andrew J; Defries, Gail; Russell, Neil K; Harper, Simon J F; Jah, Asif; Saeb-Parsy, Kourosh; Pettigrew, Gavin J; Watson, Christopher J E

2017-04-01

Exocrine drainage following pancreas transplantation can be achieved by drainage into the bladder or bowel, the latter typically by direct duodeno-jejunostomy; the use of Roux-en-Y enteric drainage is uncommon. We report a retrospective analysis of a single-centre experience of Roux-en-Y enteric drainage following pancreas transplantation. Over a 14-year period (2001-2015), 204 consecutive adult pancreas transplants were performed (96.6% simultaneous pancreas and kidney transplants), of which 26.0% were from donors after circulatory death (DCD). During a median follow-up of 67 months (range 13-183 months), 14 (6.9%) recipients experienced complications related to their enteric drainage. Complications during follow-up included early enteric anastomotic haemorrhage (five patients), non-anastomotic enteric bleeding (one patient), small bowel obstruction (four patients) and graft duodenal perforation (two within 6 weeks, five beyond 12 months). No recipient lost their graft as a direct result of complications related to enteric drainage. Patient and pancreas graft survival at 1 year was 99.0% and 94.0% and at 5 years 91.3% and 84.9%, respectively. We conclude that Roux-en-Y enteric drainage following pancreas transplantation is a safe and effective procedure and facilitates graft salvage in the event of graft duodenal perforation. © 2017 Steunstichting ESOT.

Solid Cattle Manure Less Prone to Phosphorus Loss in Tile Drainage Water.

PubMed

Wang, Y T; Zhang, T Q; Tan, C S; Qi, Z M; Welacky, T

2018-03-01

Forms (e.g., liquid and solid) of manure influence the risk of P loss after land application. The objective of this study was to investigate the effects of P-based application of various forms of cattle manure (liquid, LCM; or solid, SCM) or inorganic P as triple superphosphate (IP) on soil P losses in tile drainage water. A 4-yr field experiment was conducted in a clay loam soil with a corn ( L.)-soybean [ (L.) Merr.] rotation in the Lake Erie basin. Over the 4 yr, the dissolved reactive P (DRP) flow-weighted mean concentration (FWMC) in tile drainage water was greater under SCM fertilization than under either IP or LCM fertilization. Despite its lower value on an annual basis, DRP FWMC rose dramatically immediately after LCM application. However, the differences in DRP FWMC did not result in detectable differences in DRP loads. Regarding particulate P and total P losses during the 4 yr, they were 68 and 47%, respectively, lower in the soils amended with SCM than in those with IP, whereas both values were similar between IP and LCM treatments. Overall, the P contained in solid cattle manure was less prone to P loss after land application. Accordingly, the present results can provide a basis for manure storage and application of best management practices designed to reduce P losses and improve crop growth. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Vacuum-assisted drainage in cardiopulmonary bypass: advantages and disadvantages.

PubMed

Carvalho Filho, Elio Barreto de; Marson, Fernando Augusto de Lima; Costa, Loredana Nilkenes Gomes da; Antunes, Nilson

2014-01-01

Systematic review of vacuum assisted drainage in cardiopulmonary bypass, demonstrating its advantages and disadvantages, by case reports and evidence about its effects on microcirculation. We conducted a systematic search on the period 1997-2012, in the databases PubMed, Medline, Lilacs and SciELO. Of the 70 selected articles, 26 were included in the review. Although the vacuum assisted drainage has significant potential for complications and requires appropriate technology and professionalism, prevailed in literature reviewed the concept that vacuum assisted drainage contributed in reducing the rate of transfusions, hemodilutions, better operative field, no significant increase in hemolysis, reduced complications surgical, use of lower prime and of smaller diameter cannulas.

A case of lung abscess successfully treated by transbronchial drainage using a guide sheath.

PubMed

Izumi, Hiroki; Kodani, Masahiro; Matsumoto, Shingo; Kawasaki, Yuji; Igishi, Tadashi; Shimizu, Eiji

2017-05-01

A 51-year-old man was diagnosed with colon cancer in September 2011, and a solitary pulmonary nodule was detected by computed tomography (CT) scan. We performed a transbronchial biopsy with endobronchial ultrasonography using a guide sheath (GS) and diagnosed lung metastasis of colon cancer. The patient experienced remittent fever after the biopsy in spite of intravenous antibiotic therapies. Moreover, his CT scan showed a large lung abscess at the biopsy site. We performed transbronchial drainage using a GS as salvage therapy. The bloody pus was successfully aspirated, and chest X-ray following the procedure showed dramatic shrinkage of the abscess.

Effects of recharge from drainage wells on quality of water in the Floridan Aquifer in the Orlando area, central Florida

USGS Publications Warehouse

Schiner, G.R.; German, E.R.

1983-01-01

Approximately 400 drainage wells in the Orlando area inject, by gravity, large quantities of stormwater runoff that may or may not be suitable for most purposes without treatment into the same freshwater zones of the Floridan aquifer tapped for public supply. The wells are used mostly to control lake levels and dispose of urban storm runoff. Recharge from drainage wells compensates for heavy withdrawals from the Floridan aquifer and helps maintain aquifer pressures that retard upward saltwater encroachment. Sixty-five supply wells and 21 drainage wells within a 16-mile radius of Orlando were sampled from September 1977 to June 1979. Most constituent concentrations were slightly higher in water from drainage wells than in water from supply wells. The most notable differences were in bacteria colony count and total nitrogen concentrations. With the exception of bacteria, water from drainage wells would generally meet the maximum contaminant levels established by the National Interim Primary and Proposed Secondary Drinking Water Regulations. (USGS)

Diagnostic value of serial measurement of C-reactive protein in serum and matrix metalloproteinase-9 in drainage fluid in the detection of infectious complications and anastomotic leakage in patients with colorectal resection.

PubMed

Kostić, Zoran; Panišić, Marina; Milev, Boško; Mijušković, Zoran; Slavković, Damjan; Ignjatović, Mile

2015-10-01

Postoperative infectious complications are one of the most important problems in surgical treatment of colorectal cancer (CRC), being present in up to 40% of patients. The aim of this paper was to establish the significance of serial measurement of C-reactive protein (CRP) in serum and matrix metalloproteinase-9 (MMP-9) in drainage fluid for the detection of infectious complications and anastomotic leakage (AL) in patients with colorectal resection. CRP and MMP-9 values in serum and drainage fluid, respectively, were measured on the first, third, fifth, and seventh postoperative day (POD) in 150 patients with colorectal resection and primary anastomosis. The values obtained were compared between the patients without complicatons and those with surgical site and remote infections and AL. Surgical site infections (SSIs) were observed in 41 (27.3%), and remote infections in 10 (6.7%) patients. Clinically evident AL was observed in 15 (10/6) patients. In 82% of the patients with SSIs, serum CRP value on POD 5 exceeded 82 mg/L, with 81% specificity. AL was reported in 85% and 92% of the patients on PODs 5 and 7, respectively, with CRP values of 77 mg/L and 90 mg/L, respectively. The specificity was 77% for POD 5 and 88% for POD 7. All the patients with CRP values exceeding 139 mg/L on POD 5 had some of SSIs and/or AL. The mean values of MMP-9 were not statistically different between the group without complications (n = 99) and the group with AL (n = 15). Serial measurement of CRP is recommended for screening of infectious complications of colorectal resection. Patients with CRP values above 139 mg/L on POD 5 cannot be discharged from hospital, and require an intensive search for infectious complications, particularly AL. MMP-9 measurement in drainage fluid is not relevant in the detection of AL in patients with colorectal resection.

CT Fluoroscopy-Guided Transsacral Intervertebral Drainage for Pyogenic Spondylodiscitis at the Lumbosacral Junction

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

Matsumoto, Tomohiro, E-mail: t-matsu@tokai-u.jp; Mine, Takahiko, E-mail: mine@tsc.u-tokai.ac.jp; Hayashi, Toshihiko, E-mail: t.hayashi@tokai.ac.jp

PurposeTo retrospectively describe the feasibility and efficacy of CT fluoroscopy-guided transsacral intervertebral drainage for pyogenic spondylodiscitis at the lumbosacral junction with a combination of two interventional radiological techniques—CT-guided bone biopsy and abscess drainage.Materials and methodsThree patients with pyogenic spondylodiscitis at the lumbosacral junction were enrolled in this study between July 2013 and December 2015. The procedure of CT fluoroscopy-guided transsacral intervertebral drainage for pyogenic spondylodiscitis at the lumbosacral junction was as follows: the sacrum at S1 pedicle was penetrated with an 11-gauge (G) bone biopsy needle to create a path for an 8-French (F) pigtail drainage catheter. The bone biopsymore » needle was withdrawn, and an 18-G needle was inserted into the intervertebral space of the lumbosacral junction. Then, a 0.038-inch guidewire was inserted into the intervertebral space. Finally, the 8-F pigtail drainage catheter was inserted over the guidewire until its tip reached the intervertebral space. All patients received six-week antibiotics treatment.ResultsSuccessful placement of the drainage catheter was achieved for each patient without procedural complications. The duration of drainage was 17–33 days. For two patients, specific organisms were isolated; thus, definitive medical therapy was possible. All patients responded well to the treatment.ConclusionsCT fluoroscopy-guided transsacral intervertebral drainage for pyogenic spondylodiscitis at the lumbosacral junction is feasible and can be effective with a combination of two interventional techniques—CT fluoroscopy-guided bone biopsy and abscess drainage.« less

Peritoneal Drainage Versus Pleural Drainage After Pediatric Cardiac Surgery.

PubMed

Gowda, Keshava Murty Narayana; Zidan, Marwan; Walters, Henry L; Delius, Ralph E; Mastropietro, Christopher W

2014-07-01

We aimed to determine whether infants undergoing cardiac surgery would more efficiently attain negative fluid balance postoperatively with passive peritoneal drainage as compared to traditional pleural drainage. A prospective, randomized study including children undergoing repair of tetralogy of Fallot (TOF) or atrioventricular septal defect (AVSD) was completed between September 2011 and June 2013. Patients were randomized to intraoperative placement of peritoneal catheter or right pleural tube in addition to the requisite mediastinal tube. The primary outcome measure was fluid balance at 48 hours postoperatively. Variables were compared using t tests or Fisher exact tests as appropriate. A total of 24 patients were enrolled (14 TOF and 10 AVSD), with 12 patients in each study group. Mean fluid balance at 48 hours was not significantly different between study groups, -41 ± 53 mL/kg in patients with periteonal drainage and -9 ± 40 mL/kg in patients with pleural drainage (P = .10). At 72 hours however, postoperative fluid balance was significantly more negative with peritoneal drainage, -52.4 ± 71.6 versus +2.0 ± 50.6 (P = .04). On subset analysis, fluid balance at 48 hours in patients with AVSD was more negative with peritoneal drainage as compared to pleural, -82 ± 51 versus -1 ± 38 mL/kg, respectively (P = .02). Fluid balance at 48 hours in patients with TOF was not significantly different between study groups. Passive peritoneal drainage may more effectively facilitate negative fluid balance when compared to pleural drainage after pediatric cardiac surgery, although this benefit is not likely universal but rather dependent on the patient's underlying physiology. © The Author(s) 2014.

Environmental controls on drainage behavior of an ephemeral stream

USGS Publications Warehouse

Blasch, K.W.; Ferré, T.P.A.; Vrugt, J.A.

2010-01-01

Streambed drainage was measured at the cessation of 26 ephemeral streamflow events in Rillito Creek, Tucson, Arizona from August 2000 to June 2002 using buried time domain reflectometry (TDR) probes. An unusual drainage response was identified, which was characterized by sharp drainage from saturation to near field capacity at each depth with an increased delay between depths. We simulated the drainage response using a variably saturated numerical flow model representing a two-layer system with a high permeability layer overlying a lower permeability layer. Both the observed data and the numerical simulation show a strong correlation between the drainage velocity and the temperature of the stream water. A linear combination of temperature and the no-flow period preceding flow explained about 90% of the measured variations in drainage velocity. Evaluation of this correlative relationship with the one-dimensional numerical flow model showed that the observed temperature fluctuations could not reproduce the magnitude of variation in the observed drainage velocity. Instead, the model results indicated that flow duration exerts the most control on drainage velocity, with the drainage velocity decreasing nonlinearly with increasing flow duration. These findings suggest flow duration is a primary control of water availability for plant uptake in near surface sediments of an ephemeral stream, an important finding for estimating the ecological risk of natural or engineered changes to streamflow patterns. Correlative analyses of soil moisture data, although easy and widely used, can result in erroneous conclusions of hydrologic cause—effect relationships, and demonstrating the need for joint physically-based numerical modeling and data synthesis for hypothesis testing to support quantitative risk analysis.

Heavy metals in agricultural landscapes as hazards to human and ecosystem health: a case study on zinc and cadmium in drainage channel sediments.

PubMed

Savic, Radovan; Ondrasek, Gabrijel; Josimov-Dundjerski, Jasmina

2015-02-01

In agricultural systems, heavy metals pose severe risks to the health of soil-plant-animal-human continuum. Drainage channels, as integral components of agricultural landscapes, contain sediment material that can be both a source and a sink of metals and other toxic/persistent elements due to its highly reactive interfaces and strong binding affinity. The drainage channel network in a case study area of Vojvodina (Serbia) is not appropriately protected from contamination, nor is it maintained regularly (e.g. by desilting), thus endangering and potentially decreasing the ecological value of surrounding water and agricultural land resources, i.e. exposing food production to potential contaminants. In this study (2004-2012), Cd and Zn concentrations were analysed in 100 samples from 46 drainage channels sediments spread along the areas of the most intensive agricultural land use in Vojvodina. Among the samples measured, 5% had Cd and 14% had Zn concentrations above the maximally permitted levels, indicating that some drainage channel sections have been exposed to different point and non-point source pollutants. The maximum detected concentrations of the analysed elements were >50% (Zn) and were as much as 11-fold (Cd) higher than their remediation values. There is a strong need for the establishment of qualitative monitoring of channel sediment media in agro-ecosystems closely linked with complex pollution sources (intensive agriculture, industry, urban zones). © 2013 Society of Chemical Industry.

Evaluation of pore-water samplers at a drainage ditch, Installation Restoration Site 4, Naval Air Station Corpus Christi, Corpus Christi, Texas, 2005–06

USGS Publications Warehouse

Vroblesky, Don A.; Casey, Clifton C.

2007-01-01

The U.S. Geological Survey, in cooperation with the Naval Facilities Engineering Command Southeast, used innovative sampling methods to investigate ground-water contamination by chlorobenzenes beneath a drainage ditch on the southwestern side of Installation Restoration Site 4, Naval Air Station Corpus Christi, Corpus Christi, Texas, during 2005-06. The drainage ditch, which is a potential receptor for ground-water contaminants from Installation Restoration Site 4, intermittently discharges water to Corpus Christi Bay. This report evaluates a new type of pore-water sampler developed for this investigation to examine the subsurface contamination beneath the drainage ditch. The new type of pore-water sampler appears to be an effective approach for long-term monitoring of ground water in the sand and organic-rich mud beneath the drainage ditch.

Experimental research on coalbed gas drainage effect and economy of long directional borehole in roof

NASA Astrophysics Data System (ADS)

Yang, Huiming; Hu, Liangping

2017-05-01

In order to study the coalbed gas drainage effect and economy of long directional roof borehole, 2 boreholes were laid out in Xinji No. 2 mine to analyze its gas drainage and investment costs comparing with high position roof borehole and high position roof roadway. The result indicates that the long directional roof borehole save investment by 44.8% and shorten the construction period by 30%, comparing with high position roof roadway for controlling gas in the working face. Investment slightly less and shorten the construction period by 47.5%, comparing with the roof high position borehole. Therefore, the method of the long directional roof borehole to drain coalbed gas in working face is the most cost-effective.

Long-Term Drainage from the Riprap Side Slope of a Surface Barrier

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

Zhang, Zhuanfang

Surface barriers designed to isolate underground nuclear waste in place are expected to function for at least 1000 years. To achieve this long design life, such barriers need to be protected with side slopes against wind- and water-induced erosion and damage by natural or human activities. However, the side slopes are usually constructed with materials coarser than the barrier. Their hydrological characteristics must be understood so that any drainage from them is considered in the barrier design and will not compromise the barrier function. The Prototype Hanford Barrier, an evapotranspiration-capillary (ETC) barrier, was constructed in 1994 at the Hanford Sitemore » in southeastern Washington state, with a gravel side slope and a riprap side slope. The soil water content in the gravel side slope and drainage from both side slopes have been monitored since the completion of construction. The monitoring results show that under natural precipitation the annual drainage rates from the two types of side slopes were very similar and about 5 times the typical recharge from local soil with natural vegetation and 40 times the barrier design criterion. The higher recharge from the side slopes results in some of the drainage migrating laterally to the region beneath the ETC barrier. This edge effect of the enhanced drainage was evaluated for a period of 1000 years by numerical simulation. The edge effect was quantified by the amount of water across the barrier edges and the affecting distance of the barrier edges. These results indicate that design features can be adjusted to reduce the edge effect when necessary.« less

Geomorphologic Analysis of Drainage Basins in Damavand Volcano Cone, Iran

NASA Astrophysics Data System (ADS)

Zareinejad, M.

2011-12-01

Damavand volcanic cone is located in the center of the Alborz chain, in the southern Caspian Sea in Iran. Damavand is a dormant volcano in Iran. It is not only the country's highest peak but also the highest mountain on the Middle East; its elevation is 5619 m. The main purpose of this paper is recognition and appraisement of drainage basins in Damavand cone from geomorphic point of view. Water causes erosion in nature in different forms and creates diverse forms on the earth surface depending on the manner of its appearance in nature. Although water is itself a former factor, it flows under morphological effect of earth surface. The difference of earth surface topography and as a result water movement on it, cause the formation of sub-basins. Identification of region drainage basins is considered as one of the requirements for Damavand cone morphometric. Thereupon, five drainage basins were identified in this research by relying on main criteria including topographic contours with 10 m intervals, drainage system, DEM map, slope map, aspect map and satellite images. (Fig 1) Area, perimeter, height classification for classifying morphological landforms in different levels, hypsometric calculations, drainage density, etc. were then calculated by using ArcGIS software. (Table 1) Damavand cone, with a height more than 5,000 meters from the sea surface, has very hard pass slopes and our purpose in this paper is to identify the effect of drainage basins conditions in the region on erosion and the formation of morphological landforms by using SPOT, ASTER, satellite images as well as papering of data in GIS environment.

Chemical (polycyclic aromatic hydrocarbon and heavy metal) levels in contaminated stormwater and sediments from a motorway dry detention pond drainage system.

PubMed

Kamalakkannan, Ragunathan; Zettel, Vic; Goubatchev, Alex; Stead-Dexter, Karen; Ward, Neil I

2004-03-01

Chemical (polycyclic aromatic hydrocarbon - PAH and heavy metal) levels in stormwater and sediment samples collected from the London Orbital (M25) motorway drainage dry detention pond at Oxted, Surrey, UK were determined. Such chemicals are derived from vehicular combustion products and the wear and tear materials deposited onto the motorway surface. Gas chromatography-mass spectrometry (GC-MS) was used for the qualitative and quantitative determination of 16 USEPA priority PAHs in motorway drainage sediments. The GC-MS method, incorporating a solid phase extraction step, provides detection limits ranging from 0.17 to 0.41 mg kg(-1)(dry weight). Almost all of the 16 USEPA listed PAHs were detected. Phenanthrene, fluoranthene, pyrene, benzo(a)anthracene, chrysene, benzo(b)fluoranthene, benzo(a)pyrene and benzo(g,h,i)perylene (PAH numbers 5, 7, 8, 9, 10, 11, 13 and 16) were among the PAHs found at "higher" levels (ranging from 0.3-10.2 mg kg(-1), dry weight) in the sediment samples. PAH levels show little change along the motorway drainage silt trap (facility for reducing the levels of suspended particulate matter in the stormwater). PAH concentrations are considerably higher in the dry detention pond outflow interceptor. Statistical analysis showed that significant correlation coefficients (based on a t-test at the 95% confidence interval) were obtained between those PAHs found at high concentrations over all of the sampling sites. Several PAHs were dispersed beyond the treatment facility and accumulation in the sediment of the deer park resulted in levels ranging from 0.3-1.6 mg kg(-1), dry weight. These PAHs found beyond the treatment facility (in the local farm deer park) may contribute a serious health threat to farm animals or even fish in the aquatic environment. Heavy metal levels (V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Mo, Cd, Sb and Pb) of the drainage stormwater and sediments were determined by inductively coupled plasma mass spectrometry (ICP-MS), with quality control evaluation using two certified reference materials. Typical detection limits were found to be below 0.1 [micro sign]g l(-1) for stormwater and 0.005 mg kg(-1) for acid digested sediments. Raised heavy metal levels were found throughout the dry detention pond facility and only decrease when the stormwater is diluted following discharge into the river Eden. Statistical analysis also confirms that some significant correlations exist between various heavy metals and PAHs. However, no overall conclusive trend is found indicating that a particular PAH is deposited in sediment relative to a specific heavy metal/s. These results raise some serious concerns about the dispersion and accumulation of chemicals in the sediments of motorway stormwater drainage systems and the need for maintenance and clean-up of contaminated material from such systems.

A comparative study of treatments for chronic subdural hematoma: burr hole drainage versus burr hole drainage with irrigation.

PubMed

Ishibashi, Akira; Yokokura, Yoshitake; Adachi, Hisashi

2011-01-01

Although chronic subdural hematoma (CSDH) is one of the most common entities encountered in neurosurgical practice, optimal surgical treatment for CSDH remains controversial. This study retrospectively compared results for CSDH between burr hole drainage alone and burr hole drainage with irrigation. Ninety-two patients with CSDH underwent surgery at our institution from January 1998 through December 2009. Fifty-eight patients received burr hole drainage alone (Group A), while 34 patients were treated using burr hole drainage with irrigation (Group B). Outcomes, recurrence rates, and death rates for the two groups were analyzed. Age, sex ratio, consciousness level on admission, radiodensity of hematoma on computed tomography before surgery, and duration of hospitalization were nearly the same in both groups. No significant differences were seen in good outcomes or death rates between groups, but poor outcomes were significantly more frequent in Group A (p=0.009). The recurrence rate was higher in Group A compared to Group B (10.3% vs. 2.9%). The authors used logistic regression analysis to identify factors associated with the outcome of CSDH, and found that duration of hospital stay, anti-coagulant therapy, presence of dementia and burr hole drainage alone were significantly associated with poor outcome of CSDH. These results indicate that burr hole drainage with irrigation has a significantly stronger association with good outcomes compared to drainage alone, and could be a reliable and effective operative method for the treatment of CSDH with a lower recurrence rate.

Influence of drainage and nutrient-solution nitrogen and potassium concentrations on the agronomic behavior of bell-pepper plants cultivated in a substrate

PubMed Central

2017-01-01

The interactive effects of N (6, 9, 12 and 15 mmol L-1) and K (3, 5, 7, and 9 mmol L-1) concentrations in nutrient solutions were evaluated on bell pepper grown in a coconut-coir substrate and fertilized without drainage. An additional treatment with drainage was evaluated using N and K concentrations of 12 and 7 mmol L-1, respectively. The hybrid Eppo cultivar of yellow bell pepper was cultivated for 252 days beginning 9 November 2012. Electrical conductivity (EC), the N and K concentrations in the substrate solution, marketable fruit yield, total dry weight and macronutrient concentrations in shoots were periodically evaluated. Fruit production was lower in the system without drainage, regardless of the N and K concentrations, compared to the recommended 10–20% drainage of the volume of nutrient solution applied. Higher K concentrations in the nutrient solution did not affect plant production in the system without drainage for the substrate with an initial K concentration of 331.3 mg L-1. Fruit yield was higher without drainage at a nutrient-solution N concentration of 10.7 mmol L-1. The upper EC limit of the substrate solution in the system without drainage was exceeded 181 days after planting. Either lower nutrient concentrations in the nutrient solution or a drainage system could thus control the EC in the substrate solution. PMID:28678884

The effects of low impact development on urban flooding under different rainfall characteristics.

PubMed

Qin, Hua-peng; Li, Zhuo-xi; Fu, Guangtao

2013-11-15

Low impact development (LID) is generally regarded as a more sustainable solution for urban stormwater management than conventional urban drainage systems. However, its effects on urban flooding at a scale of urban drainage systems have not been fully understood particularly when different rainfall characteristics are considered. In this paper, using an urbanizing catchment in China as a case study, the effects of three LID techniques (swale, permeable pavement and green roof) on urban flooding are analyzed and compared with the conventional drainage system design. A range of storm events with different rainfall amounts, durations and locations of peak intensity are considered for holistic assessment of the LID techniques. The effects are measured by the total flood volume reduction during a storm event compared to the conventional drainage system design. The results obtained indicate that all three LID scenarios are more effective in flood reduction during heavier and shorter storm events. Their performance, however, varies significantly according to the location of peak intensity. That is, swales perform best during a storm event with an early peak, permeable pavements perform best with a middle peak, and green roofs perform best with a late peak, respectively. The trends of flood reduction can be explained using a newly proposed water balance method, i.e., by comparing the effective storage depth of the LID designs with the accumulative rainfall amounts at the beginning and end of flooding in the conventional drainage system. This paper provides an insight into the performance of LID designs under different rainfall characteristics, which is essential for effective urban flood management. Copyright © 2013 Elsevier Ltd. All rights reserved.

Effect of drainage in unbound aggregate bases on flexible pavement performance.

DOT National Transportation Integrated Search

2008-05-01

It has been well demonstrated that a positive subsurface drainage is beneficial in enhancing pavement performance and thus extending pavement service life. Typical permeable base materials include asphalt/cement-treated, open-graded aggregates and un...

Effects of open drainage ditch design on bacterial and fungal communities of cold waterlogged paddy soils

PubMed Central

Qiu, Shanlian; Wang, MK; Wang, Fei; Chen, Jichen; Li, Xiaoyan; Li, Qinghua; Lin, Cheng; Lin, Xinjian

2013-01-01

A field experiment established in 1980 was conducted to evaluate the effects of open drainage ditch applied for water removal on bacterial and fungal communities of cold waterlogged paddy soils in 2011. In this experiment, traditional plate counting and temperature gradient gel electrophoresis were employed to characterize the abundance and diversity of soil bacterial and fungal communities. Four different distances from the open drainage ditch, 5, 15, 25 and 75 m with different degrees of drainage were designed for this study. Maximum populations of culturable aerobic bacteria and fungi were at 15-m distance while minimum populations were at 75-m distance. Significant differences (p < 0.05) in fungal populations were observed at all distances from open drainage ditch. The highest diversity of the bacterial community was found at a distance of 25 m, while that of the fungal community was observed at a distance of 5 m. Sequencing of excised TGGE bands indicated that the dominant bacteria at 75-m distance belonged to anaerobic or microaerobic bacteria. Relationships between microbial characteristics and soil physicochemical properties indicated that soil pH and available nitrogen contents were key factors controlling the abundance of culturable aerobic bacteria and fungi, while soil water capacity also affected the diversity of fungal community. These findings can provide the references for better design and advanced management of the drainage ditches in cold waterlogged paddy soils. PMID:24516468

Surface-water quality of coal-mine lands in Raccoon Creek Basin, Ohio

USGS Publications Warehouse

Wilson, K.S.

1985-01-01

The Ohio Department of Natural Resources, Division of Reclamation, plans to reclaim abandoned surface mines in the Raccoon Creek watershed in southern Ohio. Historic water-quality data collected between 1975 and 1983 were complied and analyzed in terms of eight selected mine-drainage characteristics to develop a data base for individual subbasin reclamation projects. Areas of mine drainage affecting Raccoon Creek basin, the study Sandy Run basin, the Hewett Fork basin, and the Little raccoon Creek basin. Surface-water-quality samples were collected from a 41-site network from November 1 through November 3, 1983, Results of the sampling reaffirmed that the major sources of mine drainage to Raccoon Creek are in the Little Raccoon Creek basin, and the Hewett Fork basin. However, water quality at the mouth of Sandy Run indicated that it is not a source of mine drainage to Raccoon Creek. Buffer Run, Goose Run, an unnamed tributary to Little Raccoon Creek, Mulga Run, and Sugar Run were the main sources of mine drainage sampled in the Little Raccoon Creek basin. All sites sampled in the East Branch Raccoon Creek basin were affected by mine drainage. This information was used to prepare a work plan for additional data collection before, during, and after reclamation. The data will be used to define the effectiveness of reclamation effects in the basin.

[Spontaneous bile duct perforation: a rare cause of acute abdominal pain during childhood].

PubMed

Ozdemir, Tunç; Akgül, Ahsen Karagözlü; Arpaz, Yağmur; Arikan, Ahmet

2008-07-01

Spontaneous perforation of the bile duct (SPBD) is a rare cause of acute abdominal pain during childhood. Pancreatico-biliary malfunction has been postulated to contribute to its etiology. Factors related to diagnosis and treatment and difference from the other common causes of acute abdominal pain are emphasized. Five patients (3 boys, 2 girls, mean age 4.6) were admitted with peritonitis and operated with initial diagnosis of perforated appendicitis. During laparotomy, SPBD was detected. Presentation, laboratory findings and operative technique of the patients were evaluated retrospectively. Common complaints were abdominal pain and bilious vomiting. Abdominal distention was present in all patients. Leukocytosis and mild hyperbilirubinemia were detected in 5, elevated serum transaminase levels in 4, hyperglycemia in 1 and constipation in 1 patient(s). Abdominal ultrasonography showed a large amount of free fluid. During laparotomy, sterile bile peritonitis was detected initially. After exploration, SPBD was seen. T-tube drainage of the bile duct was carried out. Patients were discharged after removal of the T-tubes. Pancreatico-biliary malfunction was detected in 4 of 5 patients. In patients with generalized peritonitis, elevated transaminase levels and hyperbilirubinemia, SPBD must be considered. Even though the T-tube drainage is the treatment of choice, Roux-en-Y hepatico-portoenterostomy may be mandatory in certain patients.

Effect of hydration and continuous urinary drainage on urine production in children.

PubMed

Galetseli, Marianthi; Dimitriou, Panagiotis; Tsapra, Helen; Moustaki, Maria; Nicolaidou, Polyxeni; Fretzayas, Andrew

2008-01-01

Although urine production depends on numerous physiological variables there are no quantitative data regarding the effect of bladder decompression, by means of continuous catheter drainage, on urine production. The aim of this study was to investigate this effect. The study was carried out in two stages, each consisting of two phases. The effect of two distinct orally administered amounts of water was recorded in relation to continuous bladder decompression on the changes with time of urine volume and the urine production rate. In the first stage, 35 children were randomly divided into two groups and two different hydration schemes (290 and 580 ml of water/m2) were used. After the second urination of Phase 1, continuous drainage was employed in the phase that followed (Phase 2). In the second stage, a group of 10 children participated and Phase 2 was carried out 1 day after the completion of Phase 1. It was shown that the amount of urine produced increased in accordance with the degree of hydration and doubled or tripled with continual urine drainage by catheter for the same degree of hydration and within the same time interval. This was also true for Stage 2, in which Phase 2 was performed 24 h after Phase 1, indicating that diuresis during Phase 2 (as a result of Phase 1) was negligible. It was shown that during continuous drainage of urine with bladder catheterization there is an increased need for fluids, which should be administered early.

Complications in CT-guided Procedures: Do We Really Need Postinterventional CT Control Scans?

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

Nattenmüller, Johanna, E-mail: johanna.nattenmueller@med.uni-heidelberg.de; Filsinger, Matthias, E-mail: Matthias_filsinger@web.de; Bryant, Mark, E-mail: mark.bryant@med.uni-heidelberg.de

2013-06-19

PurposeThe aim of this study is twofold: to determine the complication rate in computed tomography (CT)-guided biopsies and drainages, and to evaluate the value of postinterventional CT control scans.MethodsRetrospective analysis of 1,067 CT-guided diagnostic biopsies (n = 476) and therapeutic drainages (n = 591) in thoracic (n = 37), abdominal (n = 866), and musculoskeletal (ms) (n = 164) locations. Severity of any complication was categorized as minor or major. To assess the need for postinterventional CT control scans, it was determined whether complications were detected clinically, on peri-procedural scans or on postinterventional scans only.ResultsThe complication rate was 2.5 % in all procedures (n = 27), 4.4 % in diagnostic punctures, and 1.0 % inmore » drainages; 13.5 % in thoracic, 2.0 % in abdominal, and 3.0 % in musculoskeletal procedures. There was only 1 major complication (0.1 %). Pneumothorax (n = 14) was most frequent, followed by bleeding (n = 9), paresthesia (n = 2), material damage (n = 1), and bone fissure (n = 1). Postinterventional control acquisitions were performed in 65.7 % (701 of 1,067). Six complications were solely detectable in postinterventional control acquisitions (3 retroperitoneal bleeds, 3 pneumothoraces); all other complications were clinically detectable (n = 4) and/or visible in peri-interventional controls (n = 21).ConclusionComplications in CT-guided interventions are rare. Of these, thoracic interventions had the highest rate, while pneumothoraces and bleeding were most frequent. Most complications can be detected clinically or peri-interventionally. To reduce the radiation dose, postinterventional CT controls should not be performed routinely and should be restricted to complicated or retroperitoneal interventions only.« less

Water-quality and sediment-chemistry data of drain water and evaporation ponds from Tulare Lake Drainage District, Kings County, California March 1985 to March 1986

USGS Publications Warehouse

Fujii, Roger

1988-01-01

Trace element and major ion concentrations were measured in water samples collected monthly between March 1985 and March 1986 at the MD-1 pumping station at the Tulare Lake Drainage District evaporation ponds, Kings County, California. Samples were analyzed for selected pesticides several times during the year. Salinity, as measured by specific conductance, ranged from 11,500 to 37,600 microsiemens/centimeter; total recoverable boron ranged from 4,000 to 16,000 micrg/L; and total recoverable molybdenum ranged from 630 to 2,600 microg/L. Median concentrations of total arsenic and total selenium were 97 and 2 microg/L. Atrazine, prometone, propazine, and simazine were the only pesticides detected in water samples collected at the MD-1 pumping station. Major ions, trace elements, and selected pesticides also were analyzed in water and bottom-sediment samples from five of the southern evaporation ponds at Tulare Lake Drainage District. Water enters the ponds from the MD-1 pumping station at pond 1 and flows through the system terminating at pond 10. The water samples increased in specific conductance (21,700 to 90,200 microsiemens/centimeter) and concentrations of total arsenic (110 to 420 microg/L), total recoverable boron (12,000 to 80,000 microg/L) and total recoverable molybdenum (1,200 to 5,500 microg/L) going from pond 1 to pond 10, respectively. Pesticides were not detected in water from any of the ponds sampled. Median concentrations of total arsenic and total selenium in the bottom sediments were 4.0 and 0.9 microg/g, respectively. The only pesticides detected in bottom sediment samples from the evaporation ponds were DDD and DDE, with maximum concentration of 0.8 microg/kilogram. (Author 's abstract)

Vacuum-assisted drainage in cardiopulmonary bypass: advantages and disadvantages

PubMed Central

de Carvalho Filho, Élio Barreto; Marson, Fernando Augusto de Lima; da Costa, Loredana Nilkenes Gomes; Antunes, Nilson

2014-01-01

Systematic review of vacuum assisted drainage in cardiopulmonary bypass, demonstrating its advantages and disadvantages, by case reports and evidence about its effects on microcirculation. We conducted a systematic search on the period 1997-2012, in the databases PubMed, Medline, Lilacs and SciELO. Of the 70 selected articles, 26 were included in the review. Although the vacuum assisted drainage has significant potential for complications and requires appropriate technology and professionalism, prevailed in literature reviewed the concept that vacuum assisted drainage contributed in reducing the rate of transfusions, hemodilutions, better operative field, no significant increase in hemolysis, reduced complications surgical, use of lower prime and of smaller diameter cannulas. PMID:25140478

Comparison of Intracranial Pressure and Pressure Reactivity Index Obtained Through Pressure Measurements in the Ventricle and in the Parenchyma During and Outside Cerebrospinal Fluid Drainage Episodes in a Manipulation-Free Patient Setting.

PubMed

Klein, Samuel Patrick; Bruyninckx, Dominike; Callebaut, Ina; Depreitere, Bart

2018-01-01

We investigated the effect of cerebrospinal fluid (CSF) drainage on the intracranial pressure (ICP) signal measured in the parenchyma and the ventricle as well as the effect on the pressure reactivity index (PRx) calculated from both signals.  Ten patients were included in this prospective study. All patients received a parenchymal ICP sensor and an external ventricular drain (EVD) for CSF drainage. ICP signals (ICP-p and ICP-evd) were captured. Part of the study was a period of 90 min during which the patient was free from any manipulation, consisting of 30 min of drainage (O1), 30 min EVD closed (C) and 30 min of drainage (O2).  Mean ICP-evd and mean AMP-evd increased (3.03 and 0.46 mmHg) from O1 to C and decreased (2.12 and 0.43 mmHg) from C to O2. ICP-p and AMP-p changes were less pronounced (closing EVD: +0.81 mmHg/+0.22 mmHg; opening EVD: -0.22 mmHg/-0.05 mmHg). Mean difference between PRx-evd and PRx-p was 0.12 for O1, 0.02 for C and -0.02 for O2. The intraclass correlation coefficient for absolute agreement of single measures was 0.66 for O1, 0.77 for C and 0.69 for O2. Mean PRx differences demonstrated a significant difference between O1 versus C and O1 versus O2 but not between C versus O2.  Drainage of CSF reduces ICP magnitude and amplitude through the EVD. This effect was only marginal in parenchymal ICP measurements. In manipulation-free circumstances, agreement of PRx obtained through parenchymal and ventricular measurements was moderate to good, depending on the statistical method, and was not necessarily influenced by drainage.

Re-plumbing the coast: Untangling the effects of climate change and water management on vulnerability of coastal landscapes to saltwater incursion

NASA Astrophysics Data System (ADS)

Bhattachan, A.; BenDor, T.; Ardón, M.; Bernhardt, E. S.; Wright, J. P.; Emanuel, R. E.

2016-12-01

The Atlantic Coastal Plain of the United States has been altered drastically in the past century to support agriculture, real estate, and recreational activities. In a landscape with minimal hydraulic gradients and potentially large fluctuations in sea level, the effects of introducing artificial drainages (e.g., ditches and canals) on hydrological properties are often drastic and sometimes unpredictable. In this study, we focus on a portion of the outer coastal plain of North Carolina that ranges in elevation between 6 to -5 meters a.m.s.l. To this end, we use a high-resolution, Lidar-derived digital elevation model to study the effects of artificial drainages on landscape elevation, flow accumulation, and drainage density within an 800-km2 study area. Specifically, we use image-processing techniques to filter artificial drainages from the region and compare hydrologically relevant landscape metrics with and without these features. In general, artificial drainages lower land elevation, short-circuit otherwise natural flow paths and lead to increased ( 3 times) drainage density across the landscape. We also calculate a saltwater intrusion vulnerability index (SIVI), with and without canals and ditches, to investigate the contribution of this infrastructure to saltwater intrusion vulnerability in this low-lying coastal region. The SIVI represents the ability of the freshwater to impede the inland migration of saltwater during drought periods or as sea level rises. Our results show that the construction of artificial drainages would in fact lead to an increase in vulnerability to saltwater intrusion and this pattern is consistent across all four major land-cover (wetlands, agriculture, shrub and forest) in our study area. Thus, combined with extant saltwater impacts on freshwater-dependent landscapes across our study area, our findings are immediately relevant to this region and to similar coastal regions worldwide.

EVALUATION OF LANDFILL-LINER DESIGNS

EPA Science Inventory

The effectiveness of landfill-liner designs is evaluated in terms of the slope, drainage length, and saturated hydraulic conductivity of the lateral drainage layer, the saturated hydraulic conductivity of the soil liner, and the fraction of the area under a synthetic liner where ...

Evaluating Use of Sub-Grade Drains with PFC for Stormwater Drainage : final report.

DOT National Transportation Integrated Search

2017-08-01

The overarching objective of this project is to evaluate the effectiveness of incorporated subgrade drain (usually called underdrain) in the permeable friction course (PFC) pavement to facilitate drainage of stormwater within and on the pavemen...

Twist drill craniostomy with closed drainage for chronic subdural haematoma in the elderly: an effective method.

PubMed

Ramnarayan, R; Arulmurugan, B; Wilson, Paul M; Nayar, Rani

2008-09-01

Chronic subdural haematoma is a disease of the elderly and surgery in these patients carries a much higher risk. The common surgical procedures for chronic subdural haematoma include twist drill craniostomy, burr hole evacuation or craniotomy. The aim of this study was to analyse the results of twist drill craniostomy with drainage in elderly patients with chronic subdural haematoma. Forty-two elderly patients (>65 years) with radiologically proven chronic subdural haematoma were analysed. All the patients underwent twist drill craniostomy and continuous drainage of the haematoma under local anaesthesia and total intravenous anaesthesia (TIVA). There were 24 males and 18 females. Headache and cognitive decline was seen in 50% and weakness of limbs in 60% of patients. CT scan was done in all cases. All patients underwent twist drill 2-3 cm in front of the parietal eminence under local anaesthesia. The drain was left for 24-72 h depending on the drainage. At 1 week, 88% of patients had a good outcome. Twist drill craniostomy with drainage under local anaesthesia is a safe and effective procedure for chronic subdural haematoma in the elderly and could be used as the first and only option in these people.

Effect of interfacial slip on the thin film drainage time for two equal-sized, surfactant-free drops undergoing a head-on collision: A scaling analysis

NASA Astrophysics Data System (ADS)

Ramachandran, A.; Leal, L. G.

2016-10-01

Using a scaling analysis, we assess the impact of interfacial slip on the time required for the thin liquid film between two drops undergoing a head-on collision to drain to the critical thickness for rupture by van der Waals forces. Interfacial slip is included in our continuum development using a Navier slip boundary condition, with the slip coefficient modeled using previous theories [Helfand and Tagami, J. Chem. Phys. 57, 1812 (1972), 10.1063/1.1678491; Goveas and Fredrickson, Eur. Phys. J. B 2, 79 (1998), 10.1007/s100510050228]. Slip decreases hydrodynamic resistance and speeds up film drainage. It renders the dependence of the drainage time on capillary number stronger in the spherical-film regime, but, interestingly, this dependence is altered only weakly in the dimpled-film regime. A subtle effect of slip is that it increases the range of capillary numbers in which the film remains predominantly spherical in shape during drainage (as opposed to being dimpled), leading to significantly faster drainage for these capillary numbers. Slip also leads to an increase in the critical capillary number beyond which coalescence is not possible in a head-collision.

Comparison of burbot populations across adjacent native and introduced ranges

USGS Publications Warehouse

Walters, Annika W.; Mandeville, Elizabeth G.; Saunders, W. Carl; Gerrity, Paul C.; Skorupski, Joseph A.; Underwood, Zachary E.; Gardunio, Eric I.

2017-01-01

Introduced species are a threat to biodiversity. Burbot, Lota lota, a fish native to the Wind River Drainage, Wyoming and a species of conservation concern, have been introduced into the nearby Green River Drainage, Wyoming, where they are having negative effects on native fish species. We compared these native and introduced burbot populations to evaluate potential mechanisms that could be leading to introduction success. We examined genetic ancestry, physical habitat characteristics, community composition, and burbot abundance, relative weight, and size structure between the native and introduced range to elucidate potential differences. The origin of introduced burbot in Flaming Gorge Reservoir is most likely Boysen Reservoir and several nearby river populations in the native Wind River Drainage. Burbot populations did not show consistent differences in abundance, size structure, and relative weight between drainages, though Fontenelle Reservoir, in the introduced drainage, had the largest burbot. There were also limited environmental and community composition differences, though reservoirs in the introduced drainage had lower species richness and a higher percentage of non-native fish species than the reservoir in the native drainage. Burbot introduction in the Green River Drainage is likely an example of reservoir construction creating habitat with suitable environmental conditions to allow a southwards range expansion of this cold-water species. An understanding of the factors driving introduction success can allow better management of species, both in their introduced and native range.

Extension of local front reconstruction method with controlled coalescence model

NASA Astrophysics Data System (ADS)

Rajkotwala, A. H.; Mirsandi, H.; Peters, E. A. J. F.; Baltussen, M. W.; van der Geld, C. W. M.; Kuerten, J. G. M.; Kuipers, J. A. M.

2018-02-01

The physics of droplet collisions involves a wide range of length scales. This poses a challenge to accurately simulate such flows with standard fixed grid methods due to their inability to resolve all relevant scales with an affordable number of computational grid cells. A solution is to couple a fixed grid method with subgrid models that account for microscale effects. In this paper, we improved and extended the Local Front Reconstruction Method (LFRM) with a film drainage model of Zang and Law [Phys. Fluids 23, 042102 (2011)]. The new framework is first validated by (near) head-on collision of two equal tetradecane droplets using experimental film drainage times. When the experimental film drainage times are used, the LFRM method is better in predicting the droplet collisions, especially at high velocity in comparison with other fixed grid methods (i.e., the front tracking method and the coupled level set and volume of fluid method). When the film drainage model is invoked, the method shows a good qualitative match with experiments, but a quantitative correspondence of the predicted film drainage time with the experimental drainage time is not obtained indicating that further development of film drainage model is required. However, it can be safely concluded that the LFRM coupled with film drainage models is much better in predicting the collision dynamics than the traditional methods.

Delineation of a Re-establishing Drainage Network Using SPOT and Landsat Images

NASA Astrophysics Data System (ADS)

Bailey, J. E.; Self, S.; Mouginis-Mark, P. J.

2008-12-01

The 1991 eruption of Mt. Pinatubo, The Philippines, provided a unique opportunity to study the effects on the landscape of a large eruption in part because it took place after the advent of regular satellite-based observations. The eruption formed one large (>100km2) ignimbrite sheet, with over 70% of the total deposit deposited in three primary drainage basins to the west of the volcano. High-resolution (20 m/pixel) satellite images, showing the western drainage basins and surrounding region both before and after the eruption were used to observe the re-establishment and evolution of drainage networks on the newly emplaced ignimbrite sheet. Changes in the drainage networks were delineated from a time series of SPOT (Satellite Pour l'Observation de la Terre) and Landsat multi-spectral satellite images. The analysis of which was supplemented by ground- based observations. The satellite images showed that the blue prints for the new drainage systems were established early (within days of the eruption) and at a large-scale followed the pre-eruption pattern. However, the images also illustrated the ephemeral nature of many channels due to the influence of secondary pyroclastic flows, lahar- dammed lake breakouts, stream piracy and shifts due to erosion. Characteristics of the defined drainage networks were used to infer the relative influence on the lahar hazard within each drainage basin.

Forced expiratory technique, directed cough, and autogenic drainage.

PubMed

Fink, James B

2007-09-01

In health, secretions produced in the respiratory tract are cleared by mucociliary transport, cephalad airflow bias, and cough. In disease, increased secretion viscosity and volume, dyskinesia of the cilia, and ineffective cough combine to reduce secretion clearance, leading to increased risk of infection. In obstructive lung disease these conditions are further complicated by early collapse of airways, due to airway compression, which traps both gas and secretions. Techniques have been developed to optimize expiratory flow and promote airway clearance. Directed cough, forced expiratory technique, active cycle of breathing, and autogenic drainage are all more effective than placebo and comparable in therapeutic effects to postural drainage; they require no special equipment or care-provider assistance for routine use. Researchers have suggested that standard chest physical therapy with active cycle of breathing and forced expiratory technique is more effective than chest physical therapy alone. Evidence-based reviews have suggested that, though successful adoption of techniques such as autogenic drainage may require greater control and training, patients with long-term secretion management problems should be taught as many of these techniques as they can master for adoption in their therapeutic routines.

Pirfenidone inhibits fibrosis in foreign body reaction after glaucoma drainage device implantation

PubMed Central

Jung, Kyoung In; Park, Chan Kee

2016-01-01

Background The aim of this study was to investigate the antiscarring effects of pirfenidone on foreign body reaction in a rabbit model of glaucoma drainage implant surgery. Methods Adult New Zealand White rabbits had glaucoma drainage device implantation using Model FP8 Ahmed glaucoma valves. One eye was randomly assigned to receive postoperative intrableb injection of pirfenidone followed by topical treatment. The other eye underwent the same procedure but without the addition of pirfenidone. Histochemical staining and immunohistochemistry for blebs were performed. Results The degree of cellularity was smaller in the pirfenidone group than in the control group at 2 weeks post operation (P=0.005). A few foreign body giant cells were detected in the inner border of the capsule, and their numbers were similar in the control and pirfenidone groups (P>0.05). Using Masson’s trichrome stain, the inner collagen-rich layer was found to be thinner in the pirfenidone group than the control group at 4 weeks (P=0.031) and 8 weeks (P=0.022) post operation. The percentage of proliferating cell nuclear antigen-positive cells was lower in the pirfenidone group than in the control group at 2 weeks post operation (total bleb, P=0.022; inner bleb, P=0.036). Pirfenidone treatment decreased the immunoreactivity of connective tissue growth factor at 2 weeks post operation (total bleb, P=0.029; inner bleb, P=0.018). The height and area of α-smooth muscle actin expression were lower in the pirfenidone group than the control group at 2 weeks, 4 weeks, and 8 weeks post operation (all P<0.05). Conclusion Postoperative intrableb injection of pirfenidone followed by topical administration reduced fibrosis following glaucoma drainage device implantation. These findings suggest that pirfenidone may function as an antiscarring treatment in foreign body reaction after tube-shunt surgery. PMID:27143855

Initial Australasian experience with portal-enteric drainage in simultaneous pancreas-kidney transplantation.

PubMed

Kave, Ben; Yii, Ming; Bell, Roger; Kanellis, John; Scott, David; Saunder, Alan

2010-10-01

Pancreas-kidney transplantation is currently the most effective method to re-establish euglycaemia in insulin-dependent diabetics with associated renal failure. The standard technique employed has been bladder drainage of exocrine secretions coupled with systemic venous drainage ('systemic-bladder' (SB) drainage). The more physiological technique, enteric exocrine with portal venous drainage ('portal-enteric' (PE) drainage), has been utilized sparingly in the past as a result of fears of technical complications. This paper compares the Monash Medical Centre experience with both techniques. A total of 68 simultaneous pancreas-kidney transplantations were performed at Monash Medical Centre from 1991 until 2004. The first 37 received SB drainage. Since March 2001, 27 have received PE drainage. This retrospective study compared the SB group (n= 37) with the PE group (n= 27), with a 2-year follow-up, examining a number of surgical outcomes. Two-year patient (94.3 versus 96.0%), kidney (89.2 versus 85.2%), pancreas (77.9 versus 71.4%) and event-free (73.0 versus 67.7%) survivals were all similar between the SB and PE groups, respectively. Although surgery took longer in PE subjects (4 h : 47 min ± 0:48 versus 5 h : 16 min ± 1:00; P= 0.045), less intraoperative transfusions were required (1.3 ± 1.43 versus 0.52 ± 0.90; P= 0.024). Length of hospital stay and time to insulin independence were similar. Pancreas graft thrombosis rates were similar (10.8% SB versus 7.4% PE, P= 0.497). PE drainage is a safe and viable method for pancreas transplantation, which can be performed with excellent outcomes. An increased rate of complications with PE drainage has not been demonstrated in this series. © 2009 The Authors. ANZ Journal of Surgery © 2009 Royal Australasian College of Surgeons.

Ultrasound-Guided Percutaneous Drainage of Neonatal Pyometrocolpos Under Local Anesthesia

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

Algin, Oktay, E-mail: droktayalgin@gmail.com; Erdogan, Cuneyt; Kilic, Nizamettin

2011-02-15

Hydrometrocolpos is an uncommon congenital disorder with cystic dilatation of the vagina and uterus that occurs as a result of accumulated secretions from the reproductive tract due to distal genital tract obstruction. Secondary infection may also occur, resulting in pyometrocolpos, a potentially lethal disease. Immediate drainage of the cystic mass in patients determined to have pyometrocolpos is required to prevent or treat uropathy and septicemia until definitive corrective surgery can be performed. We report an unusual cause of obstructive uropathy in three infants: pyometrocolpos due to lower genital tract atresia. Ultrasound-guided percutaneous drainage of the pyometrocolpos resulted in dramatically improvedmore » clinical and laboratory findings in these patients. Ultrasound-guided percutaneous drainage under local anesthesia is a simple, minimally invasive, safe, and effective procedure that facilitates later successful corrective surgery and avoids the need for more complex drainage procedures.« less

[A study of the value of preoperative biliary-tract drainage in the treatment of periampullary tumours: the DROP-trial].

PubMed

van der Gaag, N A; Gouma, D J

2006-03-04

Surgery in patients with obstructive jaundice caused by a periampullary (pancreas, papilla, distal bile duct) tumour is associated with a higher risk of postoperative complications than in non-jaundiced patients. Preoperative biliary drainage was introduced in an attempt to improve the general condition and thus reduce postoperative morbidity and mortality. More recently, the focus has shifted towards the negative effects of drainage, such as an increase of infectious complications. This has raised doubts as to whether biliary drainage should always be performed in these patients. The project referred to above involves a randomised multicentre trial to compare the outcome of a 'preoperative biliary-drainage strategy' (standard strategy) with that of an 'early-surgery' strategy with respect to the incidence of severe complications (primary-outcome measure), hospital stay, number of invasive diagnostic tests, costs, and quality of life.

T-tube drainage versus primary closure after open common bile duct exploration.

PubMed

Gurusamy, Kurinchi Selvan; Koti, Rahul; Davidson, Brian R

2013-06-21

Between 5% and 11% of people undergoing cholecystectomy have common bile duct stones. Stones may be removed at the time of cholecystectomy by opening and clearing the common bile duct. The optimal technique is unclear. The aim is to assess the benefits and harms of T-tube drainage versus primary closure without biliary stent after open common bile duct exploration for common bile duct stones. We searched the Cochrane Hepato-Biliary Group Controlled Trials Register, Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library, MEDLINE, EMBASE, and Science Citation Index Expanded until April 2013. We included all randomised clinical trials comparing T-tube drainage versus primary closure after open common bile duct exploration. Two of four authors independently identified the studies for inclusion and extracted data. We analysed the data with both the fixed-effect and the random-effects model using Review Manager (RevMan) analyses. For each outcome we calculated the risk ratio (RR), rate ratio (RaR), or mean difference (MD) with 95% confidence interval (CI) based on intention-to-treat analysis. We included six trials randomising 359 participants, 178 to T-tube drainage and 181 to primary closure. All trials were at high risk of bias. There was no significant difference in mortality between the two groups (4/178 (weighted percentage 1.2%) in the T-tube group versus 1/181 (0.6%) in the primary closure group; RR 2.25; 95% CI 0.55 to 9.25; six trials). There was no significant difference in the serious morbidity rate between the two groups (24/136 (weighted serious morbidity rate, 145 events per 1000 patients) in the T-tube group versus 9/136 (weighted serious morbidity rate, 66 events per 1000 patients) in the primary closure group; RaR 2.19; 95% CI 0.98 to 4.91; four trials). Quality of life and return to work were not reported in any of the trials. The operating time was significantly longer in the T-tube drainage group compared with the primary closure group (MD 28.90 minutes; 95% CI 17.18 to 40.62 minutes; one trial). The hospital stay was significantly longer in the T-tube drainage group compared with the primary closure group (MD 4.72 days; 95% CI 0.83 days to 8.60 days; five trials). T-tube drainage appeared to result in significantly longer operating time and hospital stay compared with primary closure without any apparent evidence of benefit on clinically important outcomes after open common bile duct exploration. Based on the currently available evidence, there is no justification for the routine use of T-tube drainage after open common bile duct exploration in patients with common bile duct stones. T-tube drainage should not be used outside well designed randomised clinical trials. More randomised trials comparing the effects of T-tube drainage versus primary closure after open common bile duct exploration may be needed. Such trials should be conducted with low risk of bias and assessing the long-term beneficial and harmful effects of T-tube drainage, including long-term complications such as bile stricture and recurrence of common bile duct stones.

Areal distribution and concentrations of contaminants of concern in surficial streambed and lakebed sediments, Lake Erie-Lake Saint Clair Drainages, 1990-97

USGS Publications Warehouse

Rheaume, S.J.; Button, D.T.; Myers, Donna N.; Hubbell, D.L.

2001-01-01

Concerns about elevated concentrations of contaminants such as polychlorinated biphenyls and mercury in aquatic bed sediments throughout the Great Lakes Basin have resulted in a need for better understanding of the scope and severity of the problem. Various organochlorine pesticides, polychlorinated biphenyls, trace metals, and polycyclic aromatic hydrocarbons are a concern because of their ability to persist and accumulate in aquatic sediments and their association with adverse aquatic biological effects. The areal distribution and concentrations in surficial bed sediments of 20 contaminants of concern with established bed-sediment-toxicity guidelines were examined in relation to their potential effects on freshwater aquatic biota. Contaminants at more than 800 sampling locations are characterized in this report. Surficial bed-sediment-quality data collected from 1990 to 1997 in the Lake Erie?Lake Saint Clair Drainages were evaluated to reflect recent conditions. In descending order, concentrations of total polycyclic aromatic hydrocarbons, phenanthrene, total polychlorinated biphenyls, chrysene, benz[a]anthracene, benzo[a]pyrene, cadmium, lead, zinc, arsenic, and mercury were the contaminants that most commonly exceeded levels associated with probable adverse effects on aquatic benthic organisms. The highest concentrations of most of these contaminants in aquatic bed sediments are confined to the 12 specific geographic Areas of Concern identified in the 1987 Revisions to the Great Lakes Water Quality Agreement of 1972. An exception is arsenic, which was detected at concentrations exceeding threshold effect levels at many locations outside Areas of Concern.

Comparison of early period results of blood use in open heart surgery.

PubMed

Huseyin, Serhat; Yuksel, Volkan; Guclu, Orkut; Turan, Fatma Nesrin; Canbaz, Suat; Ege, Turan; Sunar, Hasan

2016-01-01

Various adverse effects of homologous blood transfusion detected particularly in open heart surgery, in which it is frequently used, lead researchers to study on autologous blood use and to evaluate the patient's blood better. Due to the complications of homologous blood transfusion, development of techniques that utilize less transfusion has become inevitable. We aimed to evaluate the effects of acute normovolemic hemodilution (ANH) in patients undergoing open heart surgery. In this study, 120 patients who underwent open heart surgery were included. Patients were grouped into three: Autologous transfusion group (Group 1), homologous transfusion group (Group 2), and those received autologous blood and homologous blood products (Group 3). Patient data regarding preoperative characteristics, biochemical parameters, drainage, extubation time, duration of stay at intensive care, atrial fibrillation (AF) development, and hospital stay were recorded. A statistically significant difference ( P < 0.005) was found in favor of autologous group (Group 1) with respect to gender, body surface area, European System for Cardiac Operative Risk Evaluation, smoking, hematocrit levels, platelet counts, urea, C-reactive protein levels, protamine use, postoperative drainage, frequency of AF development, intubation period, stay at intensive care and hospital stay, and amount of used blood products. The use of autologous blood rather than homologous transfusion is not only attenuates side effects and complications of transfusion but also positively affects postoperative recovery process. Therefore, ANH can be considered as an easy, effective, and cheap technique during open heart surgery.

Possible origin and significance of extension-parallel drainages in Arizona's metamophic core complexes

USGS Publications Warehouse

Spencer, J.E.

2000-01-01

The corrugated form of the Harcuvar, South Mountains, and Catalina metamorphic core complexes in Arizona reflects the shape of the middle Tertiary extensional detachment fault that projects over each complex. Corrugation axes are approximately parallel to the fault-displacement direction and to the footwall mylonitic lineation. The core complexes are locally incised by enigmatic, linear drainages that parallel corrugation axes and the inferred extension direction and are especially conspicuous on the crests of antiformal corrugations. These drainages have been attributed to erosional incision on a freshly denuded, planar, inclined fault ramp followed by folding that elevated and preserved some drainages on the crests of rising antiforms. According to this hypothesis, corrugations were produced by folding after subacrial exposure of detachment-fault foot-walls. An alternative hypothesis, proposed here, is as follows. In a setting where preexisting drainages cross an active normal fault, each fault-slip event will cut each drainage into two segments separated by a freshly denuded fault ramp. The upper and lower drainage segments will remain hydraulically linked after each fault-slip event if the drainage in the hanging-wall block is incised, even if the stream is on the flank of an antiformal corrugation and there is a large component of strike-slip fault movement. Maintenance of hydraulic linkage during sequential fault-slip events will guide the lengthening stream down the fault ramp as the ramp is uncovered, and stream incision will form a progressively lengthening, extension-parallel, linear drainage segment. This mechanism for linear drainage genesis is compatible with corrugations as original irregularities of the detachment fault, and does not require folding after early to middle Miocene footwall exhumations. This is desirable because many drainages are incised into nonmylonitic crystalline footwall rocks that were probably not folded under low-temperature, surface conditions. An alternative hypothesis, that drainages were localized by small fault grooves as footwalls were uncovered, is not supported by analysis of a down-plunge fault projection for the southern Rincon Mountains that shows a linear drainage aligned with the crest of a small antiformal groove on the detachment fault, but this process could have been effective elsewhere. Lineation-parallel drainages now plunge gently southwestward on the southwest ends of antiformal corrugations in the South and Buckskin Mountains, but these drainages must have originally plunged northeastward if they formed by either of the two alternative processes proposed here. Footwall exhumation and incision by northeast-flowing streams was apparently followed by core-complex arching and drainage reversal.

Comparison of effectiveness and safety of operations on the pericardium

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

Palatianos, G.M.; Thurer, R.J.; Kaiser, G.A.

1985-07-01

A ten-year experience with operations on the pericardium in 71 consecutive patients was reviewed. The patients ranged in age from nine months to 75 years old. Fifty-three patients were operated upon for pericardial effusion and 14 for pericardial constriction. Sixty-seven patients had pericarditis: 21 of them underwent subxiphoid tube drainage; ten, limited pericardiectomy; and the remaining 36, extensive pericardiectomy. There were two trauma victims who underwent diagnostic pericardiotomy. Two patients underwent excision of pericardial cysts. There was one operative death during extensive pericardiectomy for constrictive tuberculous pericarditis. Thirty-day mortality was three of 21 patients after subxiphoid tube drainage, three ofmore » ten after limited pericardiectomy and five of 36 after extensive pericardiectomy. Postoperative complications consisted of pulmonary problems in four patients (two after pericardiectomy and two after extensive pericardiectomy), cardiac arrhythmia in one patient after tube drainage and postpericardiotomy syndrome in one patient after extensive pericardiectomy. Mean follow-up was 3.2 years. Recurrent pericardial effusion occurred in two patients; one had limited pericardiectomy but did not require reoperation and one had diagnostic pericardiotomy without drainage. Six patients with persistent postirradiation pericardial effusion were treated effectively with extensive pericardiotomy. Experience indicates that subxiphoid tube drainage is effective for the treatment of pericardial effusion and safer than limited pericardiectomy, while extensive pericardiectomy is the operation of choice for pericardial constriction and radiation-related pericardial effusion.« less

Endoscopic drainage and cystoduodedonstomy in a child with pancreatic pseudocyst.

PubMed

Ateş, Ufuk; Küçük, Gönül; Çınar, Kubilay; Bahadır, Berktuğ; Bektaş, Mehmet; Göllü, Gülnur; Bingöl Koloğlu, Meltem

2017-11-01

An 11-year-old morbidly obese boy was diagnosed with pancreatic pseudocyst. Following fine needle aspiration, the cyst recurred in 1-month follow-up. Therefore, endoscopic drainage and cystoduodenostomy was performed following endosonography. Control ultrasonography (USG) revealed a completely shrunken cyst. During the 3 years of follow-up, the patient was asymptomatic with no evidence of cyst on computerized tomography scans. Endoscopic drainage and cystoduodenostomy is a minimally invasive, effective, and safe approach in the management of pancreatic pseudocysts in children.

Cerebrospinal Fluid Leak at Percutaneous Exit of Ventricular Catheter as a Crucial Risk Factor for External Ventricular Drainage-Related Infection in Adult Neurosurgical Patients.

PubMed

Park, Jaechan; Choi, Yeon-Ju; Ohk, Boram; Chang, Hyun-Ha

2018-01-01

The placement of a ventricular catheter for temporary cerebrospinal fluid (CSF) diversion is associated with a considerable risk of CSF infection. The authors investigated the effect of a CSF leak on CSF-related infection and the predisposing factors for a CSF leak. Fifty-two patients who underwent external ventricular drainage (EVD) for acute hydrocephalus associated with a subarachnoid hemorrhage or intraventricular hemorrhage (IVH) were enrolled in this prospective study. A CSF leak-detection paper (small sterilized filter paper) was applied at the percutaneous catheter exit site to check for any bloody CSF leak. In addition, radiologic and clinical data were collected. Four of the 52 patients (7.7%) developed an EVD-related CSF infection from organisms including Staphylococcus epidermidis (n = 3) and Staphylococcus hominis (n = 1). A prolonged CSF leak >1 day was detected in 9 patients (17.3%) and revealed as a significant risk factor for CSF infection with a 44.4% positive predictive value. Moreover, an IVH >10 mL was found in 11 patients (21.2%) and revealed as a significant predisposing factor for a CSF leak at the percutaneous catheter exit. A prolonged CSF leak for >1 day at the percutaneous catheter exit site is a crucial risk factor for EVD-related CSF infection and an IVH >10 mL is a predisposing factor for a CSF leak. Copyright © 2017 Elsevier Inc. All rights reserved.

Symptomatic and asymptomatic apical periodontitis associated with red complex bacteria: clinical and microbiological evaluation.

PubMed

Buonavoglia, Alessio; Latronico, Francesca; Pirani, Chiara; Greco, Maria Fiorella; Corrente, Marialaura; Prati, Carlo

2013-01-01

In this study, the association of red complex (RC) bacteria that include Treponema denticola, Tannerella forsythia and Porphyromonas gingivalis with acute, exacerbated or chronic apical periodontitis was evaluated. Seventy-one patients with periapical disease were evaluated by clinical examination and microbiological samples obtained from the root canals were analyzed by a polymerase chain reaction assay. Twenty-one (29.6%) samples were positive for RC bacteria, with T. denticola, T. forsythia and P. gingivalis being detected in 14 (19.7%), 10 (14.1%) and 6 (8.5%) samples, respectively. RC bacteria were mainly associated with acute apical periodontitis (29.2%) and phoenix abscess (63.2%), while they were only sporadically detected (7.1%) in patients with chronic apical periodontitis. Generally, RC bacteria were associated with pain and a higher frequency of intracanalar/intrasulcular pus drainage. Involvement of RC bacteria in symptomatic periapical disease should be suspected in the presence of particularly severe clinical pain and pus drainage.

Automatic, semi-automatic and manual validation of urban drainage data.

PubMed

Branisavljević, N; Prodanović, D; Pavlović, D

2010-01-01

Advances in sensor technology and the possibility of automated long distance data transmission have made continuous measurements the preferable way of monitoring urban drainage processes. Usually, the collected data have to be processed by an expert in order to detect and mark the wrong data, remove them and replace them with interpolated data. In general, the first step in detecting the wrong, anomaly data is called the data quality assessment or data validation. Data validation consists of three parts: data preparation, validation scores generation and scores interpretation. This paper will present the overall framework for the data quality improvement system, suitable for automatic, semi-automatic or manual operation. The first two steps of the validation process are explained in more detail, using several validation methods on the same set of real-case data from the Belgrade sewer system. The final part of the validation process, which is the scores interpretation, needs to be further investigated on the developed system.

Interface fluctuations during rapid drainage

NASA Astrophysics Data System (ADS)

Ayaz, Monem; Toussaint, Renaud; Schäfer, Gerhard; Jørgen Måløy, Knut; Moura, Marcel

2017-04-01

We experimentally study the interface dynamics of an immiscible fluid as it invades a monolayer of saturated porous medium through rapid drainage. The seemingly stable and continuous motion of the interface at macroscale, involves numerous abrupt pore-scale jumps and local reconfigurations of the interface. By computing the velocity fluctuations along the invasion front from sequences of images captured at high frame rate, we are able to study both the local and global behavior. The latter displays an intermittent behavior with power-law distributed avalanches in size and duration. As the system is drained potential surface energy is stored at the interface up to a given threshold in pressure. The energy released generates elastic waves at the confining plate, which we detect using piezoelectric type acoustic sensors. By detecting pore-scale events emanating from the depinning of the interface, we look to develop techniques for localizing the displacement front. To assess the quality of these techniques, optical monitoring is done in parallel using a high speed camera.

Non-invasive mapping of deep-tissue lymph nodes in live animals using a multimodal PET/MRI nanoparticle

NASA Astrophysics Data System (ADS)

Thorek, Daniel L. J.; Ulmert, David; Diop, Ndeye-Fatou M.; Lupu, Mihaela E.; Doran, Michael G.; Huang, Ruimin; Abou, Diane S.; Larson, Steven M.; Grimm, Jan

2014-01-01

The invasion status of tumour-draining lymph nodes (LNs) is a critical indicator of cancer stage and is important for treatment planning. Clinicians currently use planar scintigraphy and single-photon emission computed tomography (SPECT) with 99mTc-radiocolloid to guide biopsy and resection of LNs. However, emerging multimodality approaches such as positron emission tomography combined with magnetic resonance imaging (PET/MRI) detect sites of disease with higher sensitivity and accuracy. Here we present a multimodal nanoparticle, 89Zr-ferumoxytol, for the enhanced detection of LNs with PET/MRI. For genuine translational potential, we leverage a clinical iron oxide formulation, altered with minimal modification for radiolabelling. Axillary drainage in naive mice and from healthy and tumour-bearing prostates was investigated. We demonstrate that 89Zr-ferumoxytol can be used for high-resolution tomographic studies of lymphatic drainage in preclinical disease models. This nanoparticle platform has significant translational potential to improve preoperative planning for nodal resection and tumour staging.

Microbial community analysis in rice paddy soils irrigated by acid mine drainage contaminated water.

PubMed

Sun, Min; Xiao, Tangfu; Ning, Zengping; Xiao, Enzong; Sun, Weimin

2015-03-01

Five rice paddy soils located in southwest China were selected for geochemical and microbial community analysis. These rice fields were irrigated with river water which was contaminated by Fe-S-rich acid mine drainage. Microbial communities were characterized by high-throughput sequencing, which showed 39 different phyla/groups in these samples. Among these phyla/groups, Proteobacteria was the most abundant phylum in all samples. Chloroflexi, Acidobacteria, Nitrospirae, and Bacteroidetes exhibited higher relative abundances than other phyla. A number of rare and candidate phyla were also detected. Moreover, canonical correspondence analysis suggested that pH, sulfate, and nitrate were significant factors that shaped the microbial community structure. In addition, a wide diversity of Fe- and S-related bacteria, such as GOUTA19, Shewanella, Geobacter, Desulfobacca, Thiobacillus, Desulfobacterium, and Anaeromyxobacter, might be responsible for biogeochemical Fe and S cycles in the tested rice paddy soils. Among the dominant genera, GOUTA19 and Shewanella were seldom detected in rice paddy soils.

Deciphering viral presences: two novel partial giant viruses detected in marine metagenome and in a mine drainage metagenome.

PubMed

Andreani, Julien; Verneau, Jonathan; Raoult, Didier; Levasseur, Anthony; La Scola, Bernard

2018-04-10

Nucleo-cytoplasmic large DNA viruses are doubled stranded DNA viruses capable of infecting eukaryotic cells. Since the discovery of Mimivirus and Pandoravirus, there has been no doubt about their extraordinary features compared to "classic" viruses. Recently, we reported the expansion of the proposed family Pithoviridae, with the description of Cedratvirus and Orpheovirus, two new viruses related to Pithoviruses. Studying the major capsid protein of Orpheovirus, we detected a homologous sequence in a mine drainage metagenome. The in-depth exploration of this metagenome, using the MG-Digger program, enabled us to retrieve up to 10 contigs with clear evidence of viral sequences. Moreover, phylogenetic analyses further extended our screening with the discovery in another marine metagenome of a second virus closely related to Orpheovirus IHUMI-LCC2. This virus is a misidentified virus confused with and annotated as a Rickettsiales bacterium. It presents a partial genome size of about 170 kbp.

Final Environmental Assessment Airfield Storm Drainage System Repair Joint Base Andrews-Naval Air Facility Washington, MD

DTIC Science & Technology

2015-06-01

sediment control plan during project implementation would be expected to minimize any adverse effects on resident fish species during construction. In... Effective August 8, 2007, under the authority of the Endangered Species Act of 1973, as amended, the U.S. Fish and Wildlife Service (Service) removed...of storm sewer pipe and 122 manholes of the airfield stormwater drainage network. Summary of Anticipated Environmental Effects Associated with the

Effects of land use and geohydrology on the quality of shallow ground water in two agricultural areas in the western Lake Michigan drainages, Wisconsin

USGS Publications Warehouse

Saad, David A.

1997-01-01

 Estimated recharge dates showed that historic patterns of atrazine plus deethyl atrazine concentrations in ground water mimic historic patterns of atrazine use on corn. Concentrations in ground water that recharged prior to the early 1960s, when atrazine started to become widely used on corn in Wisconsin, were very low or not detectable. As atrazine use on corn steadily increased from the late 1960s to the late 1970s and early 1980s, detectable concentrations of atrazine plus deethyl atrazine in ground water became more common. The recharge dates of some of the highest measured concentrations of atrazine plus ethyl atrazine in ground water from both study areas correspond to the period of highest atrazine use on corn within the State.

Causes and effects of poor drainage in cranberry farms

USDA-ARS?s Scientific Manuscript database

Soils that support the growth of cranberries often cap geologic deposits of organic sediment, such as peat. However, low-permeability organic sediments may result in inadequate drainage that diminishes plant productivity and enhances fruit rot. Consequently, new constructions of cranberry farms are ...

The Effects of Rain Garden Size on Hydrologic Performance

EPA Science Inventory

Rain gardens are vegetated depressions designed to accept stormwater runoff. Manuals and guidance documents recommend sizing rain garden cells from 3% to 43% of the associated drainage area, based on factors including soil type, slope, amount of impervious cover in the drainage ...

Cost utility analysis of endoscopic biliary stent in unresectable hilar cholangiocarcinoma: decision analytic modeling approach.

PubMed

Sangchan, Apichat; Chaiyakunapruk, Nathorn; Supakankunti, Siripen; Pugkhem, Ake; Mairiang, Pisaln

2014-01-01

Endoscopic biliary drainage using metal and plastic stent in unresectable hilar cholangiocarcinoma (HCA) is widely used but little is known about their cost-effectiveness. This study evaluated the cost-utility of endoscopic metal and plastic stent drainage in unresectable complex, Bismuth type II-IV, HCA patients. Decision analytic model, Markov model, was used to evaluate cost and quality-adjusted life year (QALY) of endoscopic biliary drainage in unresectable HCA. Costs of treatment and utilities of each Markov state were retrieved from hospital charges and unresectable HCA patients from tertiary care hospital in Thailand, respectively. Transition probabilities were derived from international literature. Base case analyses and sensitivity analyses were performed. Under the base-case analysis, metal stent is more effective but more expensive than plastic stent. An incremental cost per additional QALY gained is 192,650 baht (US$ 6,318). From probabilistic sensitivity analysis, at the willingness to pay threshold of one and three times GDP per capita or 158,000 baht (US$ 5,182) and 474,000 baht (US$ 15,546), the probability of metal stent being cost-effective is 26.4% and 99.8%, respectively. Based on the WHO recommendation regarding the cost-effectiveness threshold criteria, endoscopic metal stent drainage is cost-effective compared to plastic stent in unresectable complex HCA.

Resilience of Socio-Hydrological Systems in Canadian Prairies to Agricultural Drainage: Policy Analysis and Modelling Approach

NASA Astrophysics Data System (ADS)

Wheater, H. S.; Xu, L.; Gober, P.; Pomeroy, J. W.; Wong, J.

2017-12-01

Extensive agricultural drainage of lakes and wetlands in the Canadian Prairies has led to benefits for agricultural production, but has had a substantial influence on hydrological regimes and wetland extent. There is need for the potential impacts of current policy in changing the socio-hydrological resilience of prairie wetland basins in response to agricultural drainage to be examined. Whilst wetland drainage can increase agricultural productivity, it can also reduce stocks of natural capital and decrease ecosystem services, such as pollutant retention, habitat for waterfowls, carbon sequestration, and downstream flood attenuation. Effective policies that balance drainage benefits and negative externalities have to consider pricing. This is explored here using the Cold Regions Hydrological Model for hydrological simulations and the Inclusive Wealth approach for modelling in support of cost-benefit analysis. Inclusive wealth aggregates the value of natural, human, and technological assets used to produce social welfare. A shadow price, defined as the marginal change in social value for a marginal change in the current stock quantity, is used to valuate assets that contribute to social welfare. The shadow price of each asset is estimated by taking into account the social and economic benefits and external losses of wetland services caused by wetland drainage. The coupled model was applied to the Smith Creek Research Basin in south-eastern Saskatchewan, Canada where wetland drainage has caused major alterations of the hydrological regime including increased peak flows, discharge volumes and duration of streamflow. Changes in depressional storage in wetlands was used to calculate the corresponding changes of inclusive wealth over a 30-year period under the impacts from the limitation proposed in the Agricultural Water Management Strategy of Saskatchewan. The adjusted societal values of drainage demonstrate the dynamics between changes in hydrological conditions of wetland basins and social welfare, which help to evaluate potential impacts of the current policy on the resilience and sustainability of socio-hydrological systems. The results also help determine effective goals for management to maximize the societal benefits of drainage and minimize its negative impacts on ecosystem functions.

Application of Spatial Neural Network Model for Optimal Operation of Urban Drainage System

NASA Astrophysics Data System (ADS)

KIM, B. J.; Lee, J. Y.; KIM, H. I.; Son, A. L.; Han, K. Y.

2017-12-01

The significance of real-time operation of drainage pump and warning system for inundation becomes recently increased in order to coping with runoff by high intensity precipitation such as localized heavy rain that frequently and suddenly happen. However existing operation of drainage pump station has been made a decision according to opinion of manager based on stage because of not expecting exact time that peak discharge occur in pump station. Therefore the scale of pump station has been excessively estimated. Although it is necessary to perform quick and accurate inundation in analysis downtown area due to huge property damage from flood and typhoon, previous studies contained risk deducting incorrect result that differs from actual result owing to the diffusion aspect of flow by effect on building and road. The purpose of this study is to develop the data driven model for the real-time operation of drainage pump station and two-dimensional inundation analysis that are improved the problems of the existing hydrology and hydrological model. Neuro-Fuzzy system for real time prediction about stage was developed by estimating the type and number of membership function. Based on forecasting stage, it was decided when pump machine begin to work and how much water scoop up by using penalizing genetic algorithm. It is practicable to forecast stage, optimize pump operation and simulate inundation analysis in real time through the methodologies suggested in this study. This study can greatly contribute to the establishment of disaster information map that prevent and mitigate inundation in urban drainage area. The applicability of the development model for the five drainage pump stations in the Mapo drainage area was verified. It is considered to be able to effectively manage urban drainage facilities in the development of these operating rules. Keywords : Urban flooding; Geo-ANFIS method; Optimal operation; Drainage system; AcknowlegementThis research was supported by a grant (17AWMP-B079625-04) from Water Management Research Program funded by Ministry of Land, Infrastructure and Transport of Korean government.

Short-Term Effect of Autogenic Drainage on Ventilation Inhomogeneity in Adult Subjects With Stable Non-Cystic Fibrosis Bronchiectasis.

PubMed

Poncin, William; Reychler, Grégory; Leeuwerck, Noémie; Bauwens, Nathalie; Aubriot, Anne-Sophie; Nader, Candice; Liistro, Giuseppe; Gohy, Sophie

2017-05-01

Lung clearance index (LCI), a measure of ventilation inhomogeneity derived from a multiple-breath washout test, is a promising tool for assessing airway function in patients with non-cystic fibrosis bronchiectasis. However, it is unknown whether ventilation inhomogeneity could improve after successful elimination of excessive secretions within bronchiectasis. The objective of this work was to assess the short-term effects of lung secretion clearance using the autogenic drainage technique on standard lung function tests and LCI in subjects with non-cystic fibrosis bronchiectasis. Nitrogen-based multiple-breath washout, spirometry, and body plethysmography tests were performed 30 min before autogenic drainage in adults with stable non-cystic fibrosis bronchiectasis. The autogenic drainage session was followed by a 5-min break, after which the tests were repeated in the same order. Sputum expectorated during autogenic drainage was quantified as dry weight and correlated with change between post- and pre-measurements (Δ). Paired t test or Wilcoxon signed-rank tests were used to compare pre- and post-autogenic drainage measurement outcomes. A P value of ≤.05 was considered as statistically significant. Twenty-four subjects were studied (18 females, median age [range]: 65 [21-81] y). Mean ± SD LCI significantly improved after autogenic drainage (10.88 ± 2.62 vs 10.53 ± 2.35, P = .042). However, only 20% of subjects with mucus hyperproduction during autogenic drainage had a ΔLCI that exceeded measurement variability. The percent of predicted slow vital capacity (SVC%) also slightly improved (88.7 ± 19.3% vs 90 ± 19.1%, P = .02). ΔLCI was inversely related to dry sputum weight (r = -.48, P = .02) and ΔSVC% (r = -.64, P = .001). ΔSVC% also correlated with dry sputum weight (r = 0.46, P = .02). In adults with non-cystic fibrosis bronchiectasis and mucus hypersecretion, autogenic drainage improved ventilation inhomogeneity. LCI change may be the result of the maximum recruited lung volume and the amount of cleared mucus secretion. (ClinicalTrials.gov registration NCT02411981.). Copyright © 2017 by Daedalus Enterprises.

Systematic review and meta-analysis of initial management of pneumothorax in adults: Intercostal tube drainage versus other invasive methods

PubMed Central

Park, Incheol; Kim, Kyung Hwan; Park, Junseok; Shin, Dong Wun

2017-01-01

Objectives The ideal invasive management as initial approach for pneumothorax (PTX) is still under debate. The purpose of this systematic review and meta-analysis was to examine the evidence for the effectiveness of intercostal tube drainage and other various invasive methods as the initial approach to all subtypes of PTX in adults. Methods Three databases were searched from inception to May 29, 2016: MEDLINE, EMBASE, and the Cochrane CENTRAL. Randomised controlled trials that evaluated intercostal tube drainage as the control and various invasive methods as the intervention for the initial approach to PTX in adults were included. The primary outcome was the early success rate of each method, and the risk ratios (RRs) were used for an effect size measure. The secondary outcomes were recurrence rate, hospitalization rate, hospital stay, and complications. Results Seven studies met our inclusion criteria. Interventions were aspiration in six studies and catheterization connected to a one-way valve in one study. Meta-analyses were conducted for early success rate, recurrence rate, hospitalization rate, and hospital stay. Aspiration was inferior to intercostal tube drainage in terms of early success rate (RR = 0.82, confidence interval [CI] = 0.72 to 0.95, I2 = 0%). While aspiration and intercostal tube drainage showed no significant difference in the recurrence rate (RR = 0.84, CI = 0.57 to 1.23, I2 = 0%), aspiration had shorter hospital stay than intercostal tube drainage (mean difference = -1.73, CI = -2.33 to -1.13, I2 = 0%). Aspiration had lower hospitalization rate than intercostal tube drainage, but marked heterogeneity was present (RR = 0.38, CI = 0.19 to 0.76, I2 = 85%). Conclusion Aspiration was inferior to intercostal tube drainage in terms of early resolution, but it had shorter hospital stay. The recurrence rate of aspiration and intercostal tube drainage did not differ significantly. The efficacy of catheterization connected to a one-way valve was inconclusive because of the small number of relevant studies. (Registration of study protocol: PROSPERO, CRD42016037866) PMID:28640890

Systematic review and meta-analysis of initial management of pneumothorax in adults: Intercostal tube drainage versus other invasive methods.

PubMed

Kim, Min Joung; Park, Incheol; Park, Joon Min; Kim, Kyung Hwan; Park, Junseok; Shin, Dong Wun

2017-01-01

The ideal invasive management as initial approach for pneumothorax (PTX) is still under debate. The purpose of this systematic review and meta-analysis was to examine the evidence for the effectiveness of intercostal tube drainage and other various invasive methods as the initial approach to all subtypes of PTX in adults. Three databases were searched from inception to May 29, 2016: MEDLINE, EMBASE, and the Cochrane CENTRAL. Randomised controlled trials that evaluated intercostal tube drainage as the control and various invasive methods as the intervention for the initial approach to PTX in adults were included. The primary outcome was the early success rate of each method, and the risk ratios (RRs) were used for an effect size measure. The secondary outcomes were recurrence rate, hospitalization rate, hospital stay, and complications. Seven studies met our inclusion criteria. Interventions were aspiration in six studies and catheterization connected to a one-way valve in one study. Meta-analyses were conducted for early success rate, recurrence rate, hospitalization rate, and hospital stay. Aspiration was inferior to intercostal tube drainage in terms of early success rate (RR = 0.82, confidence interval [CI] = 0.72 to 0.95, I2 = 0%). While aspiration and intercostal tube drainage showed no significant difference in the recurrence rate (RR = 0.84, CI = 0.57 to 1.23, I2 = 0%), aspiration had shorter hospital stay than intercostal tube drainage (mean difference = -1.73, CI = -2.33 to -1.13, I2 = 0%). Aspiration had lower hospitalization rate than intercostal tube drainage, but marked heterogeneity was present (RR = 0.38, CI = 0.19 to 0.76, I2 = 85%). Aspiration was inferior to intercostal tube drainage in terms of early resolution, but it had shorter hospital stay. The recurrence rate of aspiration and intercostal tube drainage did not differ significantly. The efficacy of catheterization connected to a one-way valve was inconclusive because of the small number of relevant studies. (Registration of study protocol: PROSPERO, CRD42016037866).

Reducing nitrate loss in tile drainage water with cover crops and water-table management systems.

PubMed

Drury, C F; Tan, C S; Welacky, T W; Reynolds, W D; Zhang, T Q; Oloya, T O; McLaughlin, N B; Gaynor, J D

2014-03-01

Nitrate lost from agricultural soils is an economic cost to producers, an environmental concern when it enters rivers and lakes, and a health risk when it enters wells and aquifers used for drinking water. Planting a winter wheat cover crop (CC) and/or use of controlled tile drainage-subirrigation (CDS) may reduce losses of nitrate (NO) relative to no cover crop (NCC) and/or traditional unrestricted tile drainage (UTD). A 6-yr (1999-2005) corn-soybean study was conducted to determine the effectiveness of CC+CDS, CC+UTD, NCC+CDS, and NCC+UTD treatments for reducing NO loss. Flow volume and NO concentration in surface runoff and tile drainage were measured continuously, and CC reduced the 5-yr flow-weighted mean (FWM) NO concentration in tile drainage water by 21 to 38% and cumulative NO loss by 14 to 16% relative to NCC. Controlled tile drainage-subirrigation reduced FWM NO concentration by 15 to 33% and cumulative NO loss by 38 to 39% relative to UTD. When CC and CDS were combined, 5-yr cumulative FWM NO concentrations and loss in tile drainage were decreased by 47% (from 9.45 to 4.99 mg N L and from 102 to 53.6 kg N ha) relative to NCC+UTD. The reductions in runoff and concomitant increases in tile drainage under CC occurred primarily because of increases in near-surface soil hydraulic conductivity. Cover crops increased corn grain yields by 4 to 7% in 2004 increased 3-yr average soybean yields by 8 to 15%, whereas CDS did not affect corn or soybean yields over the 6 yr. The combined use of a cover crop and water-table management system was highly effective for reducing NO loss from cool, humid agricultural soils. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Spatio-Temporal Detection of the Thiomonas Population and the Thiomonas Arsenite Oxidase Involved in Natural Arsenite Attenuation Processes in the Carnoulès Acid Mine Drainage

PubMed Central

Hovasse, Agnès; Bruneel, Odile; Casiot, Corinne; Desoeuvre, Angélique; Farasin, Julien; Hery, Marina; Van Dorsselaer, Alain; Carapito, Christine; Arsène-Ploetze, Florence

2016-01-01

The acid mine drainage (AMD) impacted creek of the Carnoulès mine (Southern France) is characterized by acid waters with a high heavy metal content. The microbial community inhabiting this AMD was extensively studied using isolation, metagenomic and metaproteomic methods, and the results showed that a natural arsenic (and iron) attenuation process involving the arsenite oxidase activity of several Thiomonas strains occurs at this site. A sensitive quantitative Selected Reaction Monitoring (SRM)-based proteomic approach was developed for detecting and quantifying the two subunits of the arsenite oxidase and RpoA of two different Thiomonas groups. Using this approach combined with FISH and pyrosequencing-based 16S rRNA gene sequence analysis, it was established here for the first time that these Thiomonas strains are ubiquitously present in minor proportions in this AMD and that they express the key enzymes involved in natural remediation processes at various locations and time points. In addition to these findings, this study also confirms that targeted proteomics applied at the community level can be used to detect weakly abundant proteins in situ. PMID:26870729

The value of programmable shunt valves for the management of subdural collections in patients with hydrocephalus.

PubMed

Pachatouridis, Dimitrios; Alexiou, George A; Mihos, Evaggelos; Fotakopoulos, George; Voulgaris, Spyridon

2013-01-01

The aim of the present study was to assess the value of electromagnetic programmable shunt valves for the treatment of subdural collections. Adult patients with hydrocephalus of various causes that were treated with programmable shunt valves during the last ten years were retrospectively studied. In 127 patients, 139 electromagnetic programmable shunt valves were implanted. A nontraumatic subdural fluid collection was detected in 12 patients. The treatment of these patients consisted of reprogramming of the valve's opening pressure. In 5 patients small subdural hematomas were detected; 4 of these patients were treated by raising the opening pressure alone and one patient required surgical drainage and change of the pressure setting. Traumatic chronic subdural hematomas were detected in 6 patients. These patients were treated by surgical drainage and readjustment of the valve's opening pressure. The ability to treat a shunt-related complication, such as a subdural fluid collection, by reprogramming the valve's opening pressure to a higher setting is an advantage over nonprogrammable valves, and it enables the opening pressure to be slowly lowered once the fluid collection is reabsorbed. Based on our results, we believe that programmable shunt valves should be preferred.

The Value of Programmable Shunt Valves for the Management of Subdural Collections in Patients with Hydrocephalus

PubMed Central

Alexiou, George A.; Mihos, Evaggelos; Fotakopoulos, George; Voulgaris, Spyridon

2013-01-01

Background. The aim of the present study was to assess the value of electromagnetic programmable shunt valves for the treatment of subdural collections. Methods. Adult patients with hydrocephalus of various causes that were treated with programmable shunt valves during the last ten years were retrospectively studied. In 127 patients, 139 electromagnetic programmable shunt valves were implanted. Results. A nontraumatic subdural fluid collection was detected in 12 patients. The treatment of these patients consisted of reprogramming of the valve's opening pressure. In 5 patients small subdural hematomas were detected; 4 of these patients were treated by raising the opening pressure alone and one patient required surgical drainage and change of the pressure setting. Traumatic chronic subdural hematomas were detected in 6 patients. These patients were treated by surgical drainage and readjustment of the valve's opening pressure. Conclusion. The ability to treat a shunt-related complication, such as a subdural fluid collection, by reprogramming the valve's opening pressure to a higher setting is an advantage over nonprogrammable valves, and it enables the opening pressure to be slowly lowered once the fluid collection is reabsorbed. Based on our results, we believe that programmable shunt valves should be preferred. PMID:24453855

Does the usage of digital chest drainage systems reduce pleural inflammation and volume of pleural effusion following oncologic pulmonary resection?-A prospective randomized trial.

PubMed

De Waele, Michèle; Agzarian, John; Hanna, Waël C; Schieman, Colin; Finley, Christian J; Macri, Joseph; Schneider, Laura; Schnurr, Terri; Farrokhyar, Forough; Radford, Katherine; Nair, Parameswaran; Shargall, Yaron

2017-06-01

Prolonged air leak and high-volume pleural drainage are the most common causes for delays in chest tube removal following lung resection. While digital pleural drainage systems have been successfully used in the management of post-operative air leak, their effect on pleural drainage and inflammation has not been studied before. We hypothesized that digital drainage systems (as compared to traditional analog continuous suction), using intermittent balanced suction, are associated with decreased pleural inflammation and postoperative drainage volumes, thus leading to earlier chest tube removal. One hundred and three [103] patients were enrolled and randomized to either analog (n=50) or digital (n=53) drainage systems following oncologic lung resection. Chest tubes were removed according to standardized, pre-defined protocol. Inflammatory mediators [interleukin-1B (IL-1B), 6, 8, tumour necrosis factor-alpha (TNF-α)] in pleural fluid and serum were measured and analysed. The primary outcome of interest was the difference in total volume of postoperative fluid drainage. Secondary outcome measures included duration of chest tube in-situ, prolonged air-leak incidence, length of hospital stay and the correlation between pleural effusion formation, degree of inflammation and type of drainage system used. There was no significant difference in total amount of fluid drained or length of hospital stay between the two groups. A trend for shorter chest tube duration was found with the digital system when compared to the analog (P=0.055). Comparison of inflammatory mediator levels revealed no significant differences between digital and analog drainage systems. The incidence of prolonged post-operative air leak was significantly higher when using the analog system (9 versus 2 patients; P=0.025). Lobectomy was associated with longer chest tube duration (P=0.001) and increased fluid drainage when compared to sub-lobar resection (P<0.001), regardless of drainage system. Use of post-lung resection digital drainage does not appear to decrease pleural fluid formation, but is associated with decreased prolonged air leaks. Total pleural effusion volumes did not differ with the type of drainage system used. These findings support previously established benefits of the digital system in decreasing prolonged air leaks, but the advantages do not appear to extend to decreased pleural fluid formation.

Evaluating influence of active tectonics on spatial distribution pattern of floods along eastern Tamil Nadu, India

NASA Astrophysics Data System (ADS)

Selvakumar, R.; Ramasamy, SM.

2014-12-01

Flooding is a naturally recurrent phenomenon that causes severe damage to lives and property. Predictions on flood-prone zones are made based on intensity-duration of rainfall, carrying capacity of drainage, and natural or man-made obstructions. Particularly, the lower part of the drainage system and its adjacent geomorphic landforms like floodplains and deltaic plains are considered for analysis, but stagnation in parts of basins that are far away from major riverine systems is less unveiled. Similarly, uncharacteristic flooding in the upper and middle parts of drainage, especially in zones of an anomalous drainage pattern, is also least understood. Even though topographic differences are attributed for such anomalous spatial occurrence of floods, its genetic cause has to be identified for effective management practice. Added to structural and lithological variations, tectonic movements too impart micro-scale terrain undulations. Because active tectonic movements are slow-occurring, long-term geological processes, its resultant topographical variations and drainage anomalies are least correlated with floods. The recent floods of Tamil Nadu also exhibit a unique distribution pattern emphasizing the role of tectonics over it. Hence a detailed geoinformatics-based analysis was carried out to envisage the relationship between spatial distribution of flood and active tectonic elements such as regional arches and deeps, block faults, and graben and drainage anomalies such as deflected drainage, compressed meander, and eyed drainages. The analysis reveals that micro-scale topographic highs and lows imparted by active tectonic movements and its further induced drainage anomalies have substantially controlled the distribution pattern of flood.

Superoxide and nitric oxide production by Kupffer cells in rats with obstructive jaundice: effect of internal and external drainage.

PubMed

Li, Wen; Chan, Angus C W; Lau, James Y W; Lee, Danny W H; Ng, Enders K W; Sung, Joseph J Y; Chung, S C Sydney

2004-02-01

The role of Kupffer cells in obstructive jaundice (OJ) has not been fully understood. The aims of the present study were to measure superoxide and nitric oxide (NO) production by Kupffer cells in experimental OJ in rats and to investigate the response to internal and external biliary drainage. Eighty male Sprague-Dawley rats were assigned to four groups: sham operation, OJ, and internal and external biliary drainage. Kupffer cells were isolated on day 7 in the sham operation and OJ group, and on day 7 after drainage procedures. Cells were cultured with or without lipopolysaccharide (LPS). Superoxide production was quantified in cultured Kupffer cells at 2 h and 48 h, respectively, after cell isolation using the superoxide dismutase inhibitable ferricytochrome c reduction method. Nitrite production in cell culture supernatants was measured 48 h later using Greiss reagents. Without LPS stimulation, Kupffer cells produced comparable superoxide and nitrite in each group (P > 0.05). With LPS stimulation, Kupffer cells in the OJ group produced significantly higher superoxide anions than the other groups (P = 0.006). Nitrite production was significantly increased in the OJ group and external biliary drainage group compared to rats in the sham operation and internal drainage groups (P < 0.01). Kupffer cells from rats with OJ produce great amounts of endotoxin-mediated oxidants. Both internal and external biliary drainage can decrease the elevated superoxide production. Internal drainage is superior to external drainage for reversing the distortional capacity of NO production by Kupffer cells.

Subglacial drainage effects on surface motion on a small surge type alpine glacier on the St. Elias range, Yukon Territory, Canada.

NASA Astrophysics Data System (ADS)

Rada, C.; Schoof, C.; King, M. A.; Flowers, G. E.; Haber, E.

2017-12-01

Subglacial drainage is known to play an important role in glacier dynamics trough its influence on basal sliding. However, drainage is also one of the most poorly understood process in glacier flow due to the difficulties of observing, identifying and modeling the physics involved. In an effort to improve understanding of subglacial processes, we have monitored a small, approximately 100 m thick surge-type alpine glacier for nine years. Over 300 boreholes were instrumented with pressure transducers over a 0.5 km² in its upper ablation area, in addition to a weather station and a permanent GPS array consisting on 16 dual-frequency receivers within the study area. We study the influence of the subglacial drainage system on the glacier surface velocity. However, pressure variations in the drainage system during the melt season are dominated by diurnal oscillations.Therefore, GPS solutions have to be computed at sub-diurnal time intervals in order to explore the effects of transient diurnal pressure variations. Due to the small displacements of the surface of the glacier over those periods (4-10 cm/day), sub-diurnal solutions are dominated by errors, making it impossible to observe the diurnal variations in glacier motion. We have found that the main source of error is GPS multipath. This error source does largely cancel out when solutions are computed over 24 hour periods (or more precisely, over a sidereal day), but solution precisions decrease quickly when computed over shorter periods of time. Here we present an inverse problem approach to remove GPS multipath errors on glaciers, and use the reconstructed glacier motion to explore how the subglacial drainage morphology and effective pressure influence glacier dynamics at multiple time scales.

The effects of pleural fluid drainage on respiratory function in mechanically ventilated patients after cardiac surgery

PubMed Central

Brims, Fraser J H; Davies, Michael G; Elia, Andy; Griffiths, Mark J D

2015-01-01

Background Pleural effusions occur commonly after cardiac surgery and the effects of drainage on gas exchange in this population are not well established. We examined pulmonary function indices following drainage of pleural effusions in cardiac surgery patients. Methods We performed a retrospective study examining the effects of pleural fluid drainage on the lung function indices of patients recovering from cardiac surgery requiring mechanical ventilation for more than 7 days. We specifically analysed patients who had pleural fluid removed via an intercostal tube (ICT: drain group) compared with those of a control group (no effusion, no ICT). Results In the drain group, 52 ICTs were sited in 45 patients. The mean (SD) volume of fluid drained was 1180 (634) mL. Indices of oxygenation were significantly worse in the drain group compared with controls prior to drainage. The arterial oxygen tension (PaO2)/fractional inspired oxygen (FiO2) (P/F) ratio improved on day 1 after ICT placement (mean (SD), day 0: 31.01 (8.92) vs 37.18 (10.7); p<0.05) and both the P/F ratio and oxygenation index (OI: kPa/cm H2O=PaO2/mean airway pressure×FiO2) demonstrated sustained improvement to day 5 (P/F day 5: 39.85 (12.8); OI day 0: 2.88 (1.10) vs day 5: 4.06 (1.73); both p<0.01). The drain group patients were more likely to have an improved mode of ventilation on day 1 compared with controls (p=0.028). Conclusions Pleural effusion after cardiac surgery may impair oxygenation. Drainage of pleural fluid is associated with a rapid and sustained improvement in oxygenation. PMID:26339492

Illinois drainage water management demonstration project

USGS Publications Warehouse

Pitts, D.J.; Cooke, R.; Terrio, P.J.; ,

2004-01-01

Due to naturally high water tables and flat topography, there are approximately 4 million ha (10 million ac) of farmland artificially drained with subsurface (tile) systems in Illinois. Subsurface drainage is practiced to insure trafficable field conditions for farm equipment and to reduce crop stress from excess water within the root zone. Although drainage is essential for economic crop production, there have been some significant environmental costs. Tile drainage systems tend to intercept nutrient (nitrate) rich soil-water and shunt it to surface water. Data from numerous monitoring studies have shown that a significant amount of the total nitrate load in Illinois is being delivered to surface water from tile drainage systems. In Illinois, these drainage systems are typically installed without control mechanisms and allow the soil to drain whenever the water table is above the elevation of the tile outlet. An assessment of water quality in the tile drained areas of Illinois showed that approximately 50 percent of the nitrate load was being delivered through the tile systems during the fallow period when there was no production need for drainage to occur. In 1998, a demonstration project to introduce drainage water management to producers in Illinois was initiated by NRCS4 An initial aspect of the project was to identify producers that were willing to manage their drainage system to create a raised water table during the fallow (November-March) period. Financial assistance from two federal programs was used to assist producers in retrofitting the existing drainage systems with control structures. Growers were also provided guidance on the management of the structures for both water quality and production benefits. Some of the retrofitted systems were monitored to determine the effect of the practice on water quality. This paper provides background on the water quality impacts of tile drainage in Illinois, the status of the demonstration project, preliminary monitoring results, and other observations.

Geohydrologic reconnaissance of drainage wells in Florida

USGS Publications Warehouse

Kimrey, J.O.; Fayard, L.D.

1984-01-01

Drainage wells are used to inject surface waters directly into an aquifer, or shallow ground waters directly into a deeper aquifer, primarily by gravity. Such wells in Florida may be grouped into two broad types: (1) surface-water injection wells, and (2) interaquifer connector wells. Drainage wells of the first type are further categorized as either Floridan aquifer drainage wells or Biscayne aquifer drainage wells. Floridan aquifer drainage wells are commonly used to supplement drainage for urban areas in karst terranes of central and north Florida. Data are available for 25 wells in the Ocala, Live Oak, and Orlando areas that allow comparison of the quality of water samples from these Floridan aquifer drainage wells with allowable contaminant levels. Comparison indicates that maximum contaminant levels for turbidity, color, and iron, manganese, and lead concentrations are equaled or exceeded in some drainage-well samples, and relatively high counts for coliform bacteria are present in most wells. Biscayne aquifer drainage wells are used locally to dispose of stormwater runoff and other surplus water in southeast Florida, where large numbers of these wells have been permitted in Dade and Broward Counties. The majority of these wells are used to dispose of water from swimming pools or to dispose of heated water from air-conditioning units. The use of Biscayne aquifer drainage wells may have minimal effect on aquifer potability so long as injection of runoff and industrial wates is restricted to zones where chloride concentrations exceed 1,500 milligrams per liter. Interaquifer connector wells are used in the phosphate mining areas of Polk and Hillsborough Counties, to drain mines and recharge the Floridan aquifer. Water-quality data available from 13 connector wells indicate that samples from most of these wells exceed standards values for iron concentration and turbidity. One well yielded a highly mineralized water, and samples from 6 of the other 12 wells exceed standards values for gross alpha concentrations. (USGS)

Comparison of the South Florida Natural System Model with Pre-canal Everglades Hydrology Estimated from Historical Sources

USGS Publications Warehouse

McVoy, Christopher; Park, Winifred A.; Obeysekera, Jayantha

1996-01-01

Preservation and restoration of the remaining Everglades ecosystem is focussed on two aspects: improving upstream water quality and improving 'hydropatterns' - the timing, depth and flow of surface water. Restoration of hydropatterns requires knowledge of the original pre-canal drainage conditions as well as an understanding of the soil, topo-graphic, and vegetation changes that have taken place since canal drainage began in the 1880's. The Natural System Model (NSM), developed by the South Florida Water Management District (SFWMD) and Everglades National Park, uses estimates of pre-drainage vegetation and topography to estimate the pre-drainage hydrologic response of the Everglades. Sources of model uncertainty include: (1) the algorithms, (2) the parameters (particularly those relating to vegetation roughness and evapotranspiration), and (3) errors in the assumed pre-drainage vegetation distribution and pre-drainage topography. Other studies are concentrating on algorithmic and parameter sources of uncertainty. In this study we focus on the NSM output -- predicted hydropattern -- and evaluate this by comparison with all available direct and indirect information on pre-drainage hydropatterns. The unpublished and published literature is being searched exhaustively for observations of water depth, flow direction, flow velocity and hydroperiod, during the period prior and just after drainage (1840-1920). Additionally, a comprehensive map of soils in the Everglades region, prepared in the 1940's by personnel from the University of Florida Agricultural Experiment Station, the U.S. Soil Conservation Service, the U.S. Geological Survey, and the Everglades Drainage District, is being used to identify wetland soils and to infer the spatial distribution of pre-drainage hydrologic conditions. Detailed study of this map and other early soil and vegetation maps in light of the history of drainage activities will reveal patterns of change and possible errors in the input to the NSM. Changes in the wetland soils are important because of their effects on topography (soil subsidence) and in their role as indicators of hydropattern.

Cover cropping to reduce nitrate loss through subsurface drainage in the northern U.S. corn belt.

PubMed

Strock, J S; Porter, P M; Russelle, M P

2004-01-01

Despite the use of best management practices for nitrogen (N) application rate and timing, significant losses of nitrate nitrogen (NO3(-)-N) in drainage discharge continue to occur from row crop cropping systems. Our objective was to determine whether a autumn-seeded winter rye (Secale cereale L.) cover crop following corn (Zea mays L.) would reduce NO3(-)-N losses through subsurface tile drainage in a corn-soybean [Glycine mar (L.) Merr.] cropping system in the northern Corn Belt (USA) in a moderately well-drained soil. Both phases of the corn-soybean rotation, with and without the winter rye cover crop following corn, were established in 1998 in a Normania clay loam (fine-loamy, mixed, mesic Aquic Haplustoll) soil at Lamberton, MN. Cover cropping did not affect subsequent soybean yield, but reduced drainage discharge, flow-weighted mean nitrate concentration (FWMNC), and NO3(-)-N loss relative to winter fallow, although the magnitude of the effect varied considerably with annual precipitation. Three-year average drainage discharge was lower with a winter rye cover crop than without (p = 0.06). Over three years, subsurface tile-drainage discharge was reduced 11% and NO3(-)-N loss was reduced 13% for a corn-soybean cropping system with a rye cover crop following corn than with no rye cover crop. We estimate that establishment of a winter rye cover crop after corn will be successful in one of four years in southwestern Minnesota. Cover cropping with rye has the potential to be an effective management tool for reducing NO3(-)-N loss from subsurface drainage discharge despite challenges to establishment and spring growth in the north-central USA.

Modelling the ability of source control measures to reduce inundation risk in a community-scale urban drainage system

NASA Astrophysics Data System (ADS)

Mei, Chao; Liu, Jiahong; Wang, Hao; Shao, Weiwei; Xia, Lin; Xiang, Chenyao; Zhou, Jinjun

2018-06-01

Urban inundation is a serious challenge that increasingly confronts the residents of many cities, as well as policymakers, in the context of rapid urbanization and climate change worldwide. In recent years, source control measures (SCMs) such as green roofs, permeable pavements, rain gardens, and vegetative swales have been implemented to address flood inundation in urban settings, and proven to be cost-effective and sustainable. In order to investigate the ability of SCMs on reducing inundation in a community-scale urban drainage system, a dynamic rainfall-runoff model of a community-scale urban drainage system was developed based on SWMM. SCMs implementing scenarios were modelled under six design rainstorm events with return period ranging from 2 to 100 years, and inundation risks of the drainage system were evaluated before and after the proposed implementation of SCMs, with a risk-evaluation method based on SWMM and analytic hierarchy process (AHP). Results show that, SCMs implementation resulting in significantly reduction of hydrological indexes that related to inundation risks, range of reduction rates of average flow, peak flow, and total flooded volume of the drainage system were 28.1-72.1, 19.0-69.2, and 33.9-56.0 %, respectively, under six rainfall events with return periods ranging from 2 to 100 years. Corresponding, the inundation risks of the drainage system were significantly reduced after SCMs implementation, the risk values falling below 0.2 when the rainfall return period was less than 10 years. Simulation results confirm the effectiveness of SCMs on mitigating inundation, and quantified the potential of SCMs on reducing inundation risks in the urban drainage system, which provided scientific references for implementing SCMs for inundation control of the study area.

Primary closure versus T-tube drainage in laparoscopic common bile duct exploration: a meta-analysis of randomized clinical trials.

PubMed

Wu, Xiangsong; Yang, Yong; Dong, Ping; Gu, Jun; Lu, Jianhua; Li, Maolan; Mu, Jiasheng; Wu, Wenguang; Yang, Jiahua; Zhang, Lin; Ding, Qichen; Liu, Yingbin

2012-08-01

To compare the safety and effectiveness of primary closure with those of T-tube drainage in laparoscopic common bile duct exploration (LCBDE) for choledocholithiasis. A comprehensive search was performed in the PubMed, EmBase, and Cochrane Library databases. Only randomized controlled trials comparing primary closure with T-tube drainage in LCBDE were considered eligible for this meta-analysis. The analyzed outcome variables included postoperative mortality, overall morbidity, biliary complication rate, biliary leak rate, reoperation, operating time, postoperative hospital stay, time to abdominal drain removal, and retained stone. All calculations and statistical tests were performed using ReviewerManager 5.1.2 software. A total of 295 patients (148 patients with primary closure and 147 patients with T-tube drainage) from three trials were identified and analyzed. No deaths occurred in any of the trials. Primary closure showed significantly better results in terms of morbidity (risk ratio (RR), 0.51; 95% confidence interval (CI), 0.30 to 0.88), biliary complication without a combination of retained stone (RR, 0.44; 95% CI, 0.20 to 0.97), reoperation (RR, 0.16; 95% CI, 0.03 to 0.87), operating time (mean difference (MD), -20.72; 95% CI, -29.59 to -11.85), postoperative hospital stay (MD, -3.24; 95% CI, -3.96 to -2.52), and time to abdominal drainage removal (MD, -0.45; 95% CI, -0.86 to -0.04). Statistically significant differences were not found between the two methods in terms of biliary leak, biliary complication, and retained stones. The current meta-analysis indicates that primary closure of the common bile duct is safer and more effective than T-tube drainage for LCBDE. Therefore, we do not recommend routine performance of T-tube drainage in LCBDE.

Effects of coal mine drainage on the water quality of small receiving streams in Washington, 1975-77

USGS Publications Warehouse

Packard, F.A.; Skinner, E.L.; Fuste, L.A.

1988-01-01

Drainage from abandoned coal mines in western and central Washington has minimal environmental impact. Water quality characteristics that have the most significant environmental impact are suspended sediment and turbidity. Water quality data from 51 abandoned coal mines representing 11 major coal bearing areas indicate that less than 1% of the mine drainage has a pH of 4.5 or less. Fifty percent of the drainage is alkaline and has pH 7.0 and greater, and about 95% of the drainage has pH 6.0 and greater. Less than 2% is acidified to a pH of 5.6, a point where water and free (atmospheric) carbon dioxide are in equilibrium. The area where pH 5.6 or less is most likely to occur is in the Centralia/Chehalis mine district. No significant difference in diversity of benthic organisms was found between stations above and below the mine drainage. However, within the 50-ft downstream reach ostracods were more abundant than above the mine drainage and mayflies, stoneflies, and caddisflies were less abundant than at the control site. Correlations to water quality measurements show that these faunal changes are closely associated with iron and sulfate concentrations. (USGS)

A cost comparison of traditional drainage and SUDS in Scotland.

PubMed

Duffy, A; Jefferies, C; Waddell, G; Shanks, G; Blackwood, D; Watkins, A

2008-01-01

The Dunfermline Eastern Expansion (DEX) is a 350 ha mixed development which commenced in 1996. Downstream water quality and flooding issues necessitated a holistic approach to drainage planning and the site has become a European showcase for the application of Sustainable Urban Drainage Systems (SUDS). However, there is minimal data available regarding the real costs of operating and maintaining SUDS to ensure they continue to perform as per their design function. This remains one of the primary barriers to the uptake and adoption of SUDS. This paper reports on what is understood to be the only study in the UK where actual costs of constructing and maintaining SUDS have been compared to an equivalent traditional drainage solution. To compare SUDS costs with traditional drainage, capital and maintenance costs of underground storage chambers of analogous storage volumes were estimated. A whole life costing methodology was then applied to data gathered. The main objective was to produce a reliable and robust cost comparison between SUDS and traditional drainage. The cost analysis is supportive of SUDS and indicates that well designed and maintained SUDS are more cost effective to construct, and cost less to maintain than traditional drainage solutions which are unable to meet the environmental requirements of current legislation. (c) IWA Publishing 2008.

The role of CT-guided percutaneous drainage of loculated air collections: an institutional experience.

PubMed

Patel, Bhavik N; Morgan, Madeline; Tyler, Douglas; Paulson, Erik; Jaffe, Tracy A

2015-10-01

The purpose of this study is to describe our experience with the role of CT-guided percutaneous drainage of loculated intra-abdominal collections consisting entirely of gas. An IRB-approved retrospective study analyzing patients with air-only intra-abdominal collections over an 8-year period was undertaken. Seven patients referred for percutaneous drainage were included. Size of collections, subsequent development of fluid, and microbiological yield were determined. Clinical outcome was also analyzed. Out of 2835 patients referred for percutaneous drainage between 2004 and 2012, seven patients (5M, 2F; average age 63, range 54-85) met criteria for inclusion with CT showing air-only collections. Percutaneous drain placement (five 8 Fr, one 10 Fr, and one 12 Fr) using Seldinger technique was performed. Four patients (57%) had recently undergone surgery (2 Whipple, 1 colectomy, 1 hepatic resection) while two (29%) had a remote surgery (1 abdominoperineal resection, 1 sigmoidectomy). Despite the lack of detectable fluid on the original CT, 6 patients (86%) had air and fluid aspirated at drainage, 5 (83%) of the aspirates developed positive microbacterial cultures. Four patients (57%) presented with fever at the time of the initial scan, all of whom had positive cultures from aspirated fluid. Four patients (57%) had leukocytosis, all of whom had positive cultures from aspirated fluid. Although relatively rare in occurrence, patients with air-only intra-abdominal collections with signs of infection should be considered for percutaneous management similar to that of conventional infected fluid collections. Although fluid is not visible on CT, these collections can produce fluid that contains organisms.

Peat accumulation in drained thermokarst lake basins in continuous, ice-rich permafrost, northern Seward Peninsula, Alaska

USGS Publications Warehouse

Jones, Miriam C.; Grosse, Guido; Jones, Benjamin M.; Anthony, Katey Walter

2012-01-01

Thermokarst lakes and peat-accumulating drained lake basins cover a substantial portion of Arctic lowland landscapes, yet the role of thermokarst lake drainage and ensuing peat formation in landscape-scale carbon (C) budgets remains understudied. Here we use measurements of terrestrial peat thickness, bulk density, organic matter content, and basal radiocarbon age from permafrost cores, soil pits, and exposures in vegetated, drained lake basins to characterize regional lake drainage chronology, C accumulation rates, and the role of thermokarst-lake cycling in carbon dynamics throughout the Holocene on the northern Seward Peninsula, Alaska. Most detectable lake drainage events occurred within the last 4,000 years with the highest drainage frequency during the medieval climate anomaly. Peat accumulation rates were highest in young (50–500 years) drained lake basins (35.2 g C m−2 yr−1) and decreased exponentially with time since drainage to 9 g C m−2 yr−1 in the oldest basins. Spatial analyses of terrestrial peat depth, basal peat radiocarbon ages, basin geomorphology, and satellite-derived land surface properties (Normalized Difference Vegetation Index (NDVI); Minimum Noise Fraction (MNF)) from Landsat satellite data revealed significant relationships between peat thickness and mean basin NDVI or MNF. By upscaling observed relationships, we infer that drained thermokarst lake basins, covering 391 km2 (76%) of the 515 km2 study region, store 6.4–6.6 Tg organic C in drained lake basin terrestrial peat. Peat accumulation in drained lake basins likely serves to offset greenhouse gas release from thermokarst-impacted landscapes and should be incorporated in landscape-scale C budgets.

Effects of Orifice-Weir Outlet on Hydrology and Water Quality of a Drained Forested Watershed

Treesearch

Devendra M. Amatya; R. Wayne Skaggs; J.W. Gilliam; J.H. Hughes

2003-01-01

Orifice-weir structures at ditch outlets are proposed to reduce peak drainage rates during high flows and to store water during the growing season in poorly drained managed pine plantations. Two coastal watersheds, one conventionally drained (D1) and another with an orifice-weir outlet (D3), were monitored to examine the effects of this orifice treatment on drainage...

Evaluation of a drainage blanket in an asphalt shoulder section : interim report.

DOT National Transportation Integrated Search

1974-02-01

The aim of this research project was to develop a permeable, yet stable, hot mix asphaltic drainage system for a typical pavement section. Development of such systems should provide the Department with effective means of draining water from highway b...

Modeling of leachate recirculation using combined drainage blanket-horizontal trench systems in bioreactor landfills.

PubMed

Feng, Shi-Jin; Cao, Ben-Yi; Xie, Hai-Jian

2017-10-01

Leachate recirculation in municipal solid waste (MSW) landfills operated as bioreactors offers significant economic and environmental benefits. Combined drainage blanket (DB)-horizontal trench (HT) systems can be an alternative to single conventional recirculation approaches and can have competitive advantages. The key objectives of this study are to investigate combined drainage blanket -horizontal trench systems, to analyze the effects of applying two recirculation systems on the leachate migration in landfills, and to estimate some key design parameters (e.g., the steady-state flow rate, the influence width, and the cumulative leachate volume). It was determined that an effective recirculation model should consist of a moderate horizontal trench injection pressure head and supplementary leachate recirculated through drainage blanket, with an objective of increasing the horizontal unsaturated hydraulic conductivity and thereby allowing more leachate to flow from the horizontal trench system in a horizontal direction. In addition, design charts for engineering application were established using a dimensionless variable formulation.

Comparison of pigtail catheter with chest tube for drainage of parapneumonic effusion in children.

PubMed

Lin, Chien-Heng; Lin, Wei-Ching; Chang, Jeng-Sheng

2011-12-01

The use of thoracostomy tube for drainage of parapneumonic effusion is an important therapeutic measure. In this study, we compared the effectiveness and complications between chest tube and pigtail catheter thoracostomy for drainage of parapneumonic pleural effusion in children. We retrospectively reviewed the medical records of children with parapneumonic effusion during the period of July 2001 through December 2003. Patients who received thoracostomy with either chest tube or pigtail catheter were enrolled into this study. Medical records, such as age, sex, clinical presentation, subsequent therapies, hospital stay, laboratory data, and complications, were collected and compared between these two methods of intervention. A total of 32 patients (17 boys and 15 girls; age range, 2-17 years; mean age, 14 years) were enrolled into the study. Twenty patients were treated with traditional chest tubes, whereas 12 patients were treated with pigtail catheters. In the chest tube group, drainage failure occurred in one patient and pneumothorax occurred in two patients. In the pigtail catheter group, drainage failure occurred in two patients, but no case was complicated with pneumothorax. There were no significant differences in either drainage days or hospitalization days between the chest tube group and pigtail catheter group (6.0 ± 2.6 vs. 5.9 ± 3.8, p=0.66; 12.5 ± 5.6 vs. 17.3 ± 8.5, p=0.13). The effectiveness and complications of the pigtail catheter were comparable to those of the chest tubes. Copyright © 2011. Published by Elsevier B.V.

Effects of maize cultivation on nitrogen and phosphorus loadings to drainage channels in Central Chile.

PubMed

Corradini, Fabio; Nájera, Francisco; Casanova, Manuel; Tapia, Yasna; Singh, Ranvir; do Salazar, Osval

2015-11-01

There are concerns about the impact of maize cultivation with high applications of nitrogen (N) and phosphorus (P) on water quality in surface waters in Mediterranean Central Chile. This study estimated the contribution of N and P from maize fields to nearby drainage channels and evaluated the effects in water quality. An N and P budget was drawn up for three fields managed with a maize-fallow system, El Maitén (20.7 ha), El Naranjal (14.9 ha) and El Caleuche (4.2 ha), and water quality variables (pH, EC, dissolved oxygen, total solids, turbidity, NO3-N, NH4-N, PO4(3-), COD, total N, total P and sulphate) were monitored in nearby drainage channels. The N and P balances for the three fields indicated a high risk of N and P non-point source pollution, with fertiliser management, soil texture and climate factors determining the temporal variations in water quality parameters. Elevated levels of NH4-N and PO4(3-) in the drainage channels were usually observed during the winter period, while NO3- concentrations did not show a clear tendency. The results suggest that excessive slurry application during winter represents a very high risk of N and P runoff to drainage channels. Overall, great emphasis must be placed on good agronomic management of fields neighbouring drainage channels, including accurately calculating N and P fertiliser rates and establishing mitigation measures.

Estimation of recharge through selected drainage wells and potential effects from well closure, Orange County, Florida

USGS Publications Warehouse

Bradner, L.A.

1996-01-01

Drainage wells have been used in Orange County, Florida, and surrounding areas to alleviate flooding and to control lake levels since 1904. Over 400 drainage wells have been drilled in the county, but many are now redundant because of surface drainage systems that have been installed within the last two or three decades. Most of the drainage wells emplace water into the Upper Floridan aquifer, a zone of high transmissivity within the Floridan aquifer system. In 1992, the Orange County Stormwater Management Department identified 23 wells that were considered noncritical or redundant for current drainage control. These wells were targeted for closure to eliminate maintenance and possible contamination problems. A 3-year study (1992 through 1994) encompassed several drainage basins in the county. Inflow to 18 of the 23 drainage wells on the noncritical list and the effects of closure of these noncritical wells on the potentiometric surface of the Upper Floridan aquifer were estimated. Three sites were chosen for intensive study and were used for further extrapolation to other noncritical sites. The total average annual recharge rate through the 18 selected wells was estimated to be 9 cubic feet per second, or about 6 million gallons per day. The highest rate of long-term recharge, 4.6 cubic feet per second, was to well H-35. Several wells on the noncritical list were already plugged or had blocked intakes. Yields, or the sum of surface-water outflows and drainage-well recharge, from the drainage basins ranged from 20 to 33 inches per year. In some of the basins, all the yield from the basin was recharge through a drainage well. In other basins, most of the yield was surface outflow through canals rather than to drainage wells. The removal of the recharge from closure of the wells was simulated by superposition in a three-dimensional ground-water flow model. As a second step in the model, water was also applied to two sites in western Orange County that could receive redirected surface water. One of the sites is CONSERV II, a distribution system used to apply reclaimed water to the surficial aquifer system through rapid infiltration basins and grove irrigation. The second site, Lake Sherwood, has an extremely high downward recharge rate estimated to be at least 54 inches per year. The results from the simulations showed a decline of 1 foot or less in the potentiometric surface of the Upper Floridan aquifer with removal of the recharge and a mound of about 1 foot in the vicinity of the two sites in western Orange County. The Lake Sherwood site seems to reduce the declines caused by closure of the wells to a greater degree than the CONSERV II site, partly because the Lake Sherwood site is closer to the drainage-well basins.

[Ascites drainage at home].

PubMed

Lutjeboer, Jacob; van Erkel, Arian R; van der Hoeven, J J M Koos; van der Meer, Rutger W

2015-01-01

Ascites can lead to many symptoms, and often occurs in patients with an end-stage malignancy such as ovarian, pancreatic, colonic, or gastric cancer. Intermittent ascites drainage is applied in these patients as a palliative measure. As frequent drainage is necessary, a subcutaneously tunnelled permanent ascites catheter is a good alternative for intermittent drainage. The patient can open - and then re-close - the catheter when abdominal pressure increases. We inserted 35 subcutaneously permanent ascites catheters in the course of the past 3.5 years in the Leiden University Medical Centre. The success rate was 100% and the complication risk was 2.9%. A subcutaneously tunnelled ascites catheter is an effective and safe palliative treatment for patients with end-stage malignant disease and suffering from ascites.

Metacommunity ecology meets biogeography: effects of geographical region, spatial dynamics and environmental filtering on community structure in aquatic organisms.

PubMed

Heino, Jani; Soininen, Janne; Alahuhta, Janne; Lappalainen, Jyrki; Virtanen, Risto

2017-01-01

Metacommunity patterns and underlying processes in aquatic organisms have typically been studied within a drainage basin. We examined variation in the composition of six freshwater organismal groups across various drainage basins in Finland. We first modelled spatial structures within each drainage basin using Moran eigenvector maps. Second, we partitioned variation in community structure among three groups of predictors using constrained ordination: (1) local environmental variables, (2) spatial variables, and (3) dummy variable drainage basin identity. Third, we examined turnover and nestedness components of multiple-site beta diversity, and tested the best fit patterns of our datasets using the "elements of metacommunity structure" analysis. Our results showed that basin identity and local environmental variables were significant predictors of community structure, whereas within-basin spatial effects were typically negligible. In half of the organismal groups (diatoms, bryophytes, zooplankton), basin identity was a slightly better predictor of community structure than local environmental variables, whereas the opposite was true for the remaining three organismal groups (insects, macrophytes, fish). Both pure basin and local environmental fractions were, however, significant after accounting for the effects of the other predictor variable sets. All organismal groups exhibited high levels of beta diversity, which was mostly attributable to the turnover component. Our results showed consistent Clementsian-type metacommunity structures, suggesting that subgroups of species responded similarly to environmental factors or drainage basin limits. We conclude that aquatic communities across large scales are mostly determined by environmental and basin effects, which leads to high beta diversity and prevalence of Clementsian community types.

Simulation of the erosion and drainage development of Loess surface based on GIS

NASA Astrophysics Data System (ADS)

Wang, Chun; Tang, Guoan; Ge, Shanshan; Li, Zhanbin; Zhou, Jieyu

2006-10-01

The research probes into the temporal-spatial process of drainage development of Loess Plateau on the basis of a carefully designed experiment. In the experiment, the development of a simulated loess watershed is tested under the condition of lab-simulated rainfall. A close-range photogrammetry survey is employed to establish a series of high precision and resolution DEM (Digit Elevation Model) of the simulated loess surface. Based on the established DEM, the erosion loss, the slope distribution, the topographic index , the gully-brink, and the drainage networks are all derived and discussed through comparison analysis and experimental validation. All the efforts aim at revealing the process and mechanism of erosion and drainage development of loess surface .This study demonstrates: 1) the stimulation result can effectively reflect the truth if those experimental conditions, i.e. loess soil structure, simulated rainfall, are adjusted in accord with true situation; 2) the remarkable character of the erosion and drainage up-growth of loess surface include the drainage traced to the source, the increased of the drainage's density, the enlarged of gully, the durative variety of multiple terrain factor's mean value and its distribution, such as slope and topographic index; 3) The slope spectrum is the more felicitous terrain factor for depicting the erosion and drainage development of loess surface, including the rule of erosion and evolution process. It is the new way and mean for studying the loess physiognomy.

Protocol of the Australasian Malignant Pleural Effusion-2 (AMPLE-2) trial: a multicentre randomised study of aggressive versus symptom-guided drainage via indwelling pleural catheters.

PubMed

Azzopardi, Maree; Thomas, Rajesh; Muruganandan, Sanjeevan; Lam, David C L; Garske, Luke A; Kwan, Benjamin C H; Rashid Ali, Muhammad Redzwan S; Nguyen, Phan T; Yap, Elaine; Horwood, Fiona C; Ritchie, Alexander J; Bint, Michael; Tobin, Claire L; Shrestha, Ranjan; Piccolo, Francesco; De Chaneet, Christian C; Creaney, Jenette; Newton, Robert U; Hendrie, Delia; Murray, Kevin; Read, Catherine A; Feller-Kopman, David; Maskell, Nick A; Lee, Y C Gary

2016-07-05

Malignant pleural effusions (MPEs) can complicate most cancers, causing dyspnoea and impairing quality of life (QoL). Indwelling pleural catheters (IPCs) are a novel management approach allowing ambulatory fluid drainage and are increasingly used as an alternative to pleurodesis. IPC drainage approaches vary greatly between centres. Some advocate aggressive (usually daily) removal of fluid to provide best symptom control and chance of spontaneous pleurodesis. Daily drainages however demand considerably more resources and may increase risks of complications. Others believe that MPE care is palliative and drainage should be performed only when patients become symptomatic (often weekly to monthly). Identifying the best drainage approach will optimise patient care and healthcare resource utilisation. A multicentre, open-label randomised trial. Patients with MPE will be randomised 1:1 to daily or symptom-guided drainage regimes after IPC insertion. Patient allocation to groups will be stratified for the cancer type (mesothelioma vs others), performance status (Eastern Cooperative Oncology Group status 0-1 vs ≥2), presence of trapped lung (vs not) and prior pleurodesis (vs not). The primary outcome is the mean daily dyspnoea score, measured by a 100 mm visual analogue scale (VAS) over the first 60 days. Secondary outcomes include benefits on physical activity levels, rate of spontaneous pleurodesis, complications, hospital admission days, healthcare costs and QoL measures. Enrolment of 86 participants will detect a mean difference of VAS score of 14 mm between the treatment arms (5% significance, 90% power) assuming a common between-group SD of 18.9 mm and a 10% lost to follow-up rate. The Sir Charles Gairdner Group Human Research Ethics Committee has approved the study (number 2015-043). Results will be published in peer-reviewed journals and presented at scientific meetings. ACTRN12615000963527; Pre-results. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Effect Of Imposed Anaerobic Conditions On Metals Release From Acid-Mine Drainage Contaminated Streambed Sediments

EPA Science Inventory

Remediation of streams influenced by mine-drainage may require removal and burial of metal-containing bed sediments. Burial of aerobic sediments into an anaerobic environment may release metals, such as through reductive dissolution of metal oxyhydroxides. Mining-impacted aerob...

Quantitative real-time PCR-based assessment of tile drainage management influences on bacterial pathogens in tile drainage and groundwater.

PubMed

Liu, Linda; Cloutier, Michel; Craiovan, Emilia; Edwards, Mark; Frey, Steven K; Gottschall, Natalie; Lapen, David R; Sunohara, Mark; Topp, Edward; Khan, Izhar U H

2018-05-15

This study compared the impact of controlled tile drainage (CD) and freely draining (FD) systems on the prevalence and quantitative real-time PCR-based enumeration of four major pathogens including Arcobacter butzleri, Campylobacter jejuni, Campylobacter coli, and Helicobacter pylori in tile- and groundwater following a fall liquid swine manure (LSM) application on clay loam field plots. Although the prevalence of all target pathogens were detected in CD and FD systems, the loads of A. butzleri, C. jejuni, and C. coli were significantly lower in CD tile-water (p<0.05), in relation to FD tile-water. However, concentrations of A. butzleri were significantly greater in CD than FD tile-water (p<0.05). In shallow groundwater (1.2m depth), concentrations of A. butzleri, C. coli, and H. pylori showed no significant difference between CD and FD plots, while C. jejuni concentrations were significantly higher in FD plots (p<0.05). No impact of CD on the H. pylori was observed since quantitative detection in tile- and groundwater was scarce. Although speculative, H. pylori occurrence may have been related to the application of municipal biosolids four years prior to the LSM experiment. Overall, CD can be used to help minimize off-field export of pathogens into surface waters following manure applications to land, thereby reducing waterborne pathogen exposure risks to humans. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

Defining population structure and genetic signatures of decline in the giant garter snake (Thamnophis gigas): implications for conserving threatened species within highly altered landscapes

USGS Publications Warehouse

Wood, Dustin A.; Halstead, Brian J.; Casazza, Michael L.; Hansen, Eric C.; Wylie, Glenn D.; Vandergast, Amy

2015-01-01

Anthropogenic habitat fragmentation can disrupt the ability of species to disperse across landscapes, which can alter the levels and distribution of genetic diversity within populations and negatively impact long-term viability. The giant gartersnake (Thamnophis gigas) is a state and federally threatened species that historically occurred in the wetland habitats of California’s Great Central Valley. Despite the loss of 93 % of historic wetlands throughout the Central Valley, giant gartersnakes continue to persist in relatively small, isolated patches of highly modified agricultural wetlands. Gathering information regarding genetic diversity and effective population size represents an essential component for conservation management programs aimed at this species. Previous mitochondrial sequence studies have revealed historical patterns of differentiation, yet little is known about contemporary population structure and diversity. On the basis of 15 microsatellite loci, we estimate population structure and compare indices of genetic diversity among populations spanning seven drainage basins within the Central Valley. We sought to understand how habitat loss may have affected genetic differentiation, genetic diversity and effective population size, and what these patterns suggest in terms of management and restoration actions. We recovered five genetic clusters that were consistent with regional drainage basins, although three northern basins within the Sacramento Valley formed a single genetic cluster. Our results show that northern drainage basin populations have higher connectivity than among central and southern basins populations, and that greater differentiation exists among the more geographically isolated populations in the central and southern portion of the species’ range. Genetic diversity measures among basins were significantly different, and were generally lower in southern basin populations. Levels of inbreeding and evidence of population bottlenecks were detected in about half the populations we sampled, and effective population size estimates were well below recommended minimum thresholds to avoid inbreeding. Efforts focused on maintaining and enhancing existing wetlands to facilitate dispersal between basins and increase local effective population sizes may be critical for these otherwise isolated populations.

Contemporary suspended sediment dynamics within two partly glacierized mountain drainage basins in western Norway (Erdalen and Bødalen, inner Nordfjord)

NASA Astrophysics Data System (ADS)

Beylich, Achim A.; Laute, Katja; Storms, Joep E. A.

2017-06-01

This paper focuses on environmental controls, spatiotemporal variability and rates of contemporary fluvial suspended sediment transport in the neighboring, partly glacierized and steep Erdalen (79.5 km2) and Bødalen (60.1 km2) drainage basins in the fjord landscape of the inner Nordfjord in western Norway. Field work, including extended samplings and measurements, was conducted since 2004 in Erdalen and since 2008 in Bødalen. The distinct intra- and inter-annual temporal variability of suspended sediment transport found is mostly controlled by meteorological events, with most suspended sediment transport occurring during pluvial events in autumn (September-November), followed by mostly thermally determined glacier melt in summer (July-August), and by mostly thermally determined snowmelt in spring (April-June). Extreme rainfall events (> 70 mm d- 1) in autumn can trigger significant debris-flow activity that can cause significant transfers of suspended sediments from ice-free surface areas with sedimentary covers into main stream channels and is particularly important for fluvial suspended sediment transport. In years with occurring relevant debris-flow activity the total annual drainage-basin wide suspended sediment yields are strongly determined by these single extreme events. The proportion of glacier coverage, followed by steepness of slopes, and degree of vegetation cover in ice-free surface areas with sedimentary covers are the main controls for the detected spatial variability of suspended sediment yields. The contemporary sediment supply from glacierized surface areas and the Jostedalsbreen ice cap through different defined outlet glaciers shows a high spatial variability. The fact that the mean annual suspended sediment yield of Bødalen is with 31.3 t km- 2 yr- 1 almost twice as high as the mean annual suspended sediment yield of Erdalen (16.4 t km- 2 yr- 1) is to a large extent explained by the higher proportion of glacier coverage in Bødalen (38% of the drainage basin surface area) as compared to Erdalen (18% of the drainage basin surface area) and by a significantly higher sediment yield from the glacierized area of the Bødalen drainage basin compared to the glacierized surface area in Erdalen. When looking at the total annual mass of suspended sediments being fluvially exported from both entire drainage basin systems, the total amount of suspended sediments coming from the ice-free drainage basin surface areas altogether dominates over the total amount of suspended sediments coming from the glacierized surface area of both drainage basins. Drainage-basin wide annual suspended sediment yields are rather low when compared with yields of other partly glacierized drainage basin systems in Norway and in other cold climate environments worldwide, which is mainly due to the high resistance of the predominant gneisses towards glacial erosion and weathering, the altogether only small amounts of sediments being available within the entire drainage basin systems, the stable and nearly closed vegetation cover in the ice-free surface areas with sedimentary covers, and the efficiency of proglacial lakes in trapping sediments supplied by defined outlet glaciers. Both contemporary and long-term suspended sediment yields are altogether supply-limited. Contemporary suspended sediment transport accounts for nearly two-thirds of the total fluvial transport and, accordingly, plays an important role within the sedimentary budgets of the entire Erdalen and Bødalen drainage basins.

Relations among geology, physiography, land use, and stream habitat conditions in the Buffalo and Current River Systems, Missouri and Arkansas

USGS Publications Warehouse

Panfil, Maria S.; Jacobson, Robert B.

2001-01-01

This study investigated links between drainage-basin characteristics and stream habitat conditions in the Buffalo National River, Arkansas and the Ozark National Scenic Riverways, Missouri. It was designed as an associative study - the two parks were divided into their principle tributary drainage basins and then basin-scale and stream-habitat data sets were gathered and compared between them. Analyses explored the relative influence of different drainage-basin characteristics on stream habitat conditions. They also investigated whether a relation between land use and stream characteristics could be detected after accounting for geologic and physiographic differences among drainage basins. Data were collected for three spatial scales: tributary drainage basins, tributary stream reaches, and main-stem river segments of the Current and Buffalo Rivers. Tributary drainage-basin characteristics were inventoried using a Geographic Information System (GIS) and included aspects of drainage-basin physiography, geology, and land use. Reach-scale habitat surveys measured channel longitudinal and cross-sectional geometry, substrate particle size and embeddedness, and indicators of channel stability. Segment-scale aerial-photo based inventories measured gravel-bar area, an indicator of coarse sediment load, along main-stem rivers. Relations within and among data sets from each spatial scale were investigated using correlation analysis and multiple linear regression. Study basins encompassed physiographically distinct regions of the Ozarks. The Buffalo River system drains parts of the sandstone-dominated Boston Mountains and of the carbonate-dominated Springfield and Salem Plateaus. The Current River system is within the Salem Plateau. Analyses of drainage-basin variables highlighted the importance of these physiographic differences and demonstrated links among geology, physiography, and land-use patterns. Buffalo River tributaries have greater relief, steeper slopes, and more streamside bluffs than the Current River tributaries. Land use patterns in both river systems correlate with physiography - cleared land area is negatively associated with drainage-basin average slope. Both river systems are dominantly forested (0-35 per-cent cleared land), however, the potential for landscape disturbance may be greater in the Buffalo River system where a larger proportion of cleared land occurs on steep slopes (>15 degrees). When all drainage basins are grouped together, reach-scale channel characteristics show the strongest relations with drainage-basin physiography. Bankfull channel geometry and residual pool dimensions are positively correlated with drainage area and topographic relief variables. After accounting for differences in drainage area, channel dimensions in Buffalo River tributaries tend to be larger than in Current River tributaries. This trend is consistent with the flashy runoff and large storm flows that can be generated in rugged, sandstone-dominate terrain. Substrate particle size is also most strongly associated with physiography; particle size is positively correlated with topographic relief variables. When tributaries are subset by river system, relations with geology and land use variables become apparent. Buffalo River tributaries with larger proportions of carbonate bedrock and cleared land area have shallower channels, better-sorted, gravel-rich substrate, and more eroding banks than those with little cleared land and abundant sandstone bedrock. Gravel-bar area on the Buffalo River main stem was also larger within 1-km of carbonate-rich tributary junctions. Because geology and cleared land are themselves correlated, relations with anthropogenic and natural factors could often not be separated. Channel characteristics in the Current River system show stronger associations with physiography than with land use. Channels are shallower and have finer substrates in the less rugged, karst-rich, western basins than in the

Land use change in the last century in the Veneto floodplain: effects on network drainage density, water storage, and related consequences on flood risk

NASA Astrophysics Data System (ADS)

Prosdocimi, Massimo; Sofia, Giulia; Dalla Fontana, Giancarlo; Tarolli, Paolo

2013-04-01

In a high-density populated country such as Italy, the anthropic pressure plays a fundamental role in the alteration and the modification of the landscape. Among the most evident anthropic alterations, the most important are the urbanization processes that have been occurring since the end of the second world war. Agricultural activities, housing and other land uses have shifted due to the progressive spreading of urban areas. These modifications affect the hydrologic regimes, but municipalities often are not aware of the real impact of land cover changes on such processes and, consequently, an increase of the elements at risk of flooding is generally registered. The main objective of this work is to evaluate the impact of land cover changes in the Veneto region (north-east Italy), from 1954 to 2006, on the minor drainage network system and on its capacity to attenuate the direct runoff. The major flood event occurred between October and November 2010. The study is a typical agrarian landscape and it has been chosen considering its involvement inthe major flood of 2010 and considering also the availability of high-resolution topographic data (LiDAR-derived DTMs) and historical aerial photographs. Aerial photographs dated back to 1954 and 1981, in particular, have been used either to classify the land cover in five categories according to the first level of the CORINE land cover classification and to identify the minor drainage network. A semi-automatic approach based on the high-resolution DTM (Cazorzi et al., 2012), was also considered to identify the minor drainage network and estimate its water storage capacity. The results underline how land cover variation over the last 50 years has strongly increased the propension of the soil to produce direct runoff (increase of the Curve Number value) and it has also reduced the extent of the minor network system. As a consequence, the capacity of the agrarian minor network to attenuate and laminate a flood event is decreased as well. These analysis can be considered useful tools for a suitable land use planning in flood prone areas. References Cazorzi, F., Dalla Fontana, G., De Luca, A., Sofia, G., Tarolli, P. (2012). Drainage network detection and assessment of network storage capacity in agrarian landscape, Hydrological Processes, ISSN: 0885-6087, doi:10.1002/hyp.9224

Translating evidence-based protocol of wound drain management for total joint arthroplasty into practice: A quasi-experimental study.

PubMed

Tsang, Lap Fung; Cheng, Hang Cheong; Ho, Hon Shuen; Hsu, Yung Chak; Chow, Chiu Man; Law, Heung Wah; Fong, Lup Chau; Leung, Lok Ming; Kong, Ivy Ching Yan; Chan, Chi Wai; Sham, Alice So Yuen

2016-05-01

Although various drains have long been used in total joint replacement, evidence suggests inconsistent practice exists in the use of drainage systems including intermittently applying suction or free of drainage suction, and variations in the optimal timing for wound drain removal. A comprehensive systematic review of available evidence up to 2013 was conducted in a previous study and a protocol was adapted for clinical application according to the summary of the retrieved information (Tsang, 2015). To determine if the protocol could reduce blood loss and blood transfusion after operation and to develop a record form so as to enhance communication of drainage record amongst surgeons and nurses. A quasi-experimental time-series design was undertaken. In the conventional group, surgeons ordered free drainage if the drain output was more than 300 ml. The time of removal of the drain was based on their professional judgement. In the protocol group the method of drainage was dependant of the drainage output as was the timing of the removal of the drain. A standardized record form was developed to guide operating room and orthopaedic ward nurses to manage the drainage system. The drain was removed significantly earlier in the protocol group. Blood loss rate at the first hour of post-operation was extremely low in the protocol group due to clamping effect. Blood loss in volume during the first three hours in the protocol group was significantly lower than that in the conventional group. Only in 11.1% and 4% of cases was it necessary to clamp at the three and four hour post-operative hours. No clamping was required at the two and eight hour postoperative period. There was no significant difference in blood loss during the removal of the drain and during blood transfusion, which was required for patients upon removal of the drain in the two groups. This is the first clinical study to develop an evidence-based protocol to manage wound drain effectively in Hong Kong. Total blood loss and blood transfusions were not significantly different between the conventional and protocol groups. A standard documentation document is beneficial to enhance communication between doctors and nurses as well as to monitor and observe drainage effectively. Copyright © 2016 Elsevier Ltd. All rights reserved.

Rapid Pore Cranial Drilling With External Ventricular Drainage for Treatment of Intraventricular Hemorrhage: A 36-Year Case Series

PubMed Central

Zhang, Wei; Wei, Lin; Li, Gang; Sun, Jinlong; Jin, Peng; Yang, Jun; Wang, Daokui; Bai, Yunan; Li, Xingang; Fei, Chang; Wang, Chengwei; Wang, Baoan; Pan, Shumao; Du, Jihai; Xie, Bo; Xu, Dongfang; Xin, Changming; Wang, Jihua; Zhang, Qinglin

2015-01-01

This study aimed to describe the technique details of rapid pore cranial drilling with external ventricular drainage and document its clinical outcomes by highlighting the advantages over the traditional and modified cranial drilling technique. Intraventricular hemorrhage is one of the most severe subtypes of hemorrhagic stroke with high mortality. The amount of blood in the ventricles is associated with severity of outcomes, and fast removal of the blood clot is the key to a good prognosis. Between 1977 and 2013, 3773 patients admitted for intraventricular hemorrhage underwent rapid pore cranial drilling drainage. The therapeutic effects and clinical outcomes were retrospectively analyzed. Of these patients, 1049 (27.8%) experienced complete remission, 1788 (47.4%) had improved condition, and 936 (24.8%) died. A total of 3229 (85.6%) patients gained immediate remission. One typical case was illustrated to demonstrate the efficacy of the rapid pore drilling technique. Rapid pore cranial drilling drainage in patients with intraventricular hemorrhage is fast, effective, and provides immediate relief in patients with severe conditions. It could be a better alternative to the conventional drilling approach for treatment of intraventricular hemorrhage. A randomized controlled trial for direct comparison between the rapid pore cranial drilling drainage and conventional drilling technique is in urgent need. PMID:25590642

Rapid Pore Cranial Drilling With External Ventricular Drainage for Treatment of Intraventricular Hemorrhage: A 36-Year Case Series.

PubMed

Zhang, Wei; Wei, Lin; Li, Gang; Sun, Jinlong; Jin, Peng; Yang, Jun; Wang, Daokui; Bai, Yunan; Li, Xingang; Fei, Chang; Wang, Chengwei; Wang, Baoan; Pan, Shumao; Du, Jihai; Xie, Bo; Xu, Dongfang; Xin, Changming; Wang, Jihua; Zhang, Qinglin

2015-06-01

This study aimed to describe the technique details of rapid pore cranial drilling with external ventricular drainage and document its clinical outcomes by highlighting the advantages over the traditional and modified cranial drilling technique. Intraventricular hemorrhage is one of the most severe subtypes of hemorrhagic stroke with high mortality. The amount of blood in the ventricles is associated with severity of outcomes, and fast removal of the blood clot is the key to a good prognosis. Between 1977 and 2013, 3773 patients admitted for intraventricular hemorrhage underwent rapid pore cranial drilling drainage. The therapeutic effects and clinical outcomes were retrospectively analyzed. Of these patients, 1049 (27.8%) experienced complete remission, 1788 (47.4%) had improved condition, and 936 (24.8%) died. A total of 3229 (85.6%) patients gained immediate remission. One typical case was illustrated to demonstrate the efficacy of the rapid pore drilling technique. Rapid pore cranial drilling drainage in patients with intraventricular hemorrhage is fast, effective, and provides immediate relief in patients with severe conditions. It could be a better alternative to the conventional drilling approach for treatment of intraventricular hemorrhage. A randomized controlled trial for direct comparison between the rapid pore cranial drilling drainage and conventional drilling technique is in urgent need.

Prophylactic intra-peritoneal drain placement following pancreaticoduodenectomy: A systematic review and meta-analysis

PubMed Central

Wang, Yi-Chao; Szatmary, Peter; Zhu, Jing-Qiang; Xiong, Jun-Jie; Huang, Wei; Gomatos, Ilias; Nunes, Quentin M; Sutton, Robert; Liu, Xu-Bao

2015-01-01

AIM: To conduct a meta-analysis comparing outcomes after pancreaticoduodenectomy (PD) with or without prophylactic drainage. METHODS: Relevant comparative randomized and non-randomized studies were systemically searched based on specific inclusion and exclusion criteria. Postoperative outcomes were compared between patients with and those without routine drainage. Pooled odds ratios (OR) with 95%CI were calculated using either fixed effects or random effects models. RESULTS: One randomized controlled trial and four non-randomized comparative studies recruiting 1728 patients were analyzed. Patients without prophylactic drainage after PD had significantly higher mortality (OR = 2.32, 95%CI: 1.11-4.85; P = 0.02), despite the fact that they were associated with fewer overall complications (OR = 0.62, 95%CI: 0.48-0.82; P = 0.00), major complications (OR = 0.75, 95%CI: 0.60-0.93; P = 0.01) and readmissions (OR = 0.77, 95%CI: 0.60-0.98; P = 0.04). There were no significant differences in the rates of pancreatic fistula, intra-abdominal abscesses, postpancreatectomy hemorrhage, biliary fistula, delayed gastric emptying, reoperation or radiologic-guided drains between the two groups. CONCLUSION: Indiscriminate abandonment of intra-abdominal drainage following PD is associated with greater mortality, but lower complication rates. Future randomized trials should compare routine vs selective drainage. PMID:25741162

Drain Failure in Intra-Abdominal Abscesses Associated with Appendicitis.

PubMed

Horn, Christopher B; Coleoglou Centeno, Adrian A; Guerra, Jarot J; Mazuski, John E; Bochicchio, Grant V; Turnbull, Isaiah R

2018-04-01

Previous studies have suggested that percutaneous drainage and interval appendectomy is an effective treatment for appendicitis with associated abscess. Few studies to date have analyzed risk factors for failed drain management. We hypothesized that older patients with more co-morbidities would be at higher risk for failing conservative treatment. The 2010-2014 editions of the National Inpatient Sample (NIS) were queried for patients with diagnoses of peri-appendiceal abscesses. Minors and elective admissions were excluded. We identified patients who underwent percutaneous drainage and defined drain failure as undergoing a surgical operation after drainage but during the same inpatient visit to assess for factors associated with failure of drainage alone as a treatment. After univariable analysis, binomial logistic regression was used to assess for independent risk factors. Frequencies were analyzed by χ 2 and continuous variables by Student's t-test. A total of 2,209 patients with appendiceal abscesses received drains; 561 patients (25.4%) failed conservative management and underwent operative intervention. On univariable analysis, patients who failed conservative management were younger, more likely to be Hispanic, have more inpatient diagnoses, and to have undergone drainage earlier in the hospital course. Multivariable regression demonstrated that the number of diagnoses, female sex, and Hispanic race were predictive of failure of drainage alone. Older age, West and Midwest census regions, and later drain placement were predictive of successful treatment with drainage alone. Failure was associated with more charges and longer hospital stay but not with a higher mortality rate. Approximately a quarter of patients will fail management of appendiceal abscess with percutaneous drain placement alone. Risk factors for failure are patient complexity, female sex, earlier drainage, and Hispanic race. Failure of drainage is associated with higher total charges and longer hospital stay; however, no change in the mortality rate was noted.

Outcome of percutaneous continuous drainage of psoas abscess: A clinically guided technique.

PubMed

Dave, Bharat R; Kurupati, Ranganatha Babu; Shah, Dipak; Degulamadi, Devanand; Borgohain, Nitu; Krishnan, Ajay

2014-01-01

Percutaneous aspiration of abscesses under ultrasonography (USG) and computer tomography (CT) scan has been well described. With recurrence rate reported as high as 66%. The open drainage and percutaneous continuous drainage (PCD) has reduced the recurrence rate. The disadvantage of PCD under CT is radiation hazard and problems of asepsis. Hence a technique of clinically guided percutaneous continuous drainage of the psoas abscess without real-time imaging overcomes these problems. We describe clinically guided PCD of psoas abscess and its outcome. Twenty-nine patients with dorsolumbar spondylodiscitis without gross neural deficit with psoas abscess of size >5 cm were selected for PCD. It was done as a day care procedure under local anesthesia. Sequentially, aspiration followed by guide pin-guided trocar and catheter insertion was done without image guidance. Culture sensitivity was done and chemotherapy initiated and catheter kept till the drainage was <10 ml for 48 hours. Outcome assessment was done with relief of pain, successful abscess drainage and ODI (Oswestry Disability Index) score at 2 years. PCD was successful in all cases. Back and radicular pain improved in all cases. Average procedure time was 24.30 minutes, drain output was 234.40 ml, and the drainage duration was 7.90 days. One patient required surgical stabilisation due to progression of the spondylodiscitis resulting in instability inspite of successful drainage of abscess. Problems with the procedure were noticed in six patients. Multiple attempts (n = 2), persistent discharge (n = 1) for 2 weeks, blocked catheter (n = 2) and catheter pull out (n = 1) occurred with no effect on the outcome. The average ODI score improved from 62.47 to 5.51 at 2 years. Clinically guided PCD is an efficient, safe and easy procedure in drainage of psoas abscess.

Spatial structures of stream and hillslope drainage networks following gully erosion after wildfire

USGS Publications Warehouse

Moody, J.A.; Kinner, D.A.

2006-01-01

The drainage networks of catchment areas burned by wildfire were analysed at several scales. The smallest scale (1-1000 m2) representative of hillslopes, and the small scale (1000 m2 to 1 km2), representative of small catchments, were characterized by the analysis of field measurements. The large scale (1-1000 km2), representative of perennial stream networks, was derived from a 30-m digital elevation model and analysed by computer analysis. Scaling laws used to describe large-scale drainage networks could be extrapolated to the small scale but could not describe the smallest scale of drainage structures observed in the hillslope region. The hillslope drainage network appears to have a second-order effect that reduces the number of order 1 and order 2 streams predicted by the large-scale channel structure. This network comprises two spatial patterns of rills with width-to-depth ratios typically less than 10. One pattern is parallel rills draining nearly planar hillslope surfaces, and the other pattern is three to six converging rills draining the critical source area uphill from an order 1 channel head. The magnitude of this critical area depends on infiltration, hillslope roughness and critical shear stress for erosion of sediment, all of which can be substantially altered by wildfire. Order 1 and 2 streams were found to constitute the interface region, which is altered by a disturbance, like wildfire, from subtle unchannelized drainages in unburned catchments to incised drainages. These drainages are characterized by gullies also with width-to-depth ratios typically less than 10 in burned catchments. The regions (hillslope, interface and chanel) had different drainage network structures to collect and transfer water and sediment. Copyright ?? 2005 John Wiley & Sons, Ltd.

Impacts of soil conditioners and water table management on phosphorus loss in tile drainage from a clay loam soil.

PubMed

Zhang, T Q; Tan, C S; Zheng, Z M; Welacky, T W; Reynolds, W D

2015-03-01

Adoption of waste-derived soil conditioners and refined water management can improve soil physical quality and crop productivity of fine-textured soils. However, the impacts of these practices on water quality must be assessed to ensure environmental sustainability. We conducted a study to determine phosphorus (P) loss in tile drainage as affected by two types of soil conditioners (yard waste compost and swine manure compost) and water table management (free drainage and controlled drainage with subirrigation) in a clay loam soil under corn-soybean rotation in a 4-yr period from 1999 to 2003. Tile drainage flows were monitored and sampled on a year-round continuous basis using on-site auto-sampling systems. Water samples were analyzed for dissolved reactive P (DRP), particulate P (PP), and total P (TP). Substantially greater concentrations and losses of DRP, PP, and TP occurred with swine manure compost than with control and yard waste compost regardless of water table management. Compared with free drainage, controlled drainage with subirrigation was an effective way to reduce annual and cumulative losses of DRP, PP, and TP in tile drainage through reductions in flow volume and P concentration with control and yard waste compost but not with swine manure compost. Both DRP and TP concentrations in tile drainage were well above the water quality guideline for P, affirming that subsurface loss of P from fine-textured soils can be one critical source for freshwater eutrophication. Swine manure compost applied as a soil conditioner must be optimized by taking water quality impacts into consideration. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Effect of Physical Methods of Lymphatic Drainage on Postexercise Recovery of Mixed Martial Arts Athletes.

PubMed

Zebrowska, Aleksandra; Trybulski, Robert; Roczniok, Robert; Marcol, Wieslaw

2017-08-16

Physical methods are reported to be important for accelerating skeletal muscle regeneration, decreasing muscle soreness, and shortening of the recovery time. The aim of the study was to assess the effect of the physical methods of lymphatic drainage (PMLD) such as manual lymphatic drainage (MLD), the Bodyflow (BF) therapy, and lymphatic drainage by deep oscillation (DO) on postexercise regeneration of the forearm muscles of mixed martial arts (MMA) athletes. Eighty MMA athletes aged 27.5 ± 6.4 years were allocated to 4 groups: MLD, the BF device, DO therapy, and the control group. Blood flow velocity in the cephalic vein was measured with the ultrasound Doppler velocity meter. Maximal strength of the forearm muscles (Fmax), muscle tissue tension, pain threshold, blood lactate concentration (LA), and activity of creatine kinase were measured in all groups at rest, after the muscle fatigue test (post-ex) and then 20 minutes, 24, and 48 hours after the application of PMLD. The muscle fatigue test reduced Fmax in all subjects, but in the groups receiving MLD, DO, and BF significantly higher Fmax was observed at recovery compared with post-ex values. The application of MDL reduced the postexercise blood LA and postexercise muscle tension. The lymphatic drainage methods, whether manual or using electro-stimulation and DO, improve postexercise regeneration of the forearm muscles of MMA athletes. The methods can be an important element of therapeutic management focused on optimizing training effects and reducing the risk of injuries of the combat sports athletes.

Detection of hepatitis E virus and other livestock-related pathogens in Iowa streams

USDA-ARS?s Scientific Manuscript database

Manure application is a major source of pathogens to the environment. Through overland runoff and tile drainage, these pathogens contaminate surface water and stream bed sediment. Some of these pathogens are zoonotic that can potentially affect both animal and human health. This study examined the p...

Flooding in the future--predicting climate change, risks and responses in urban areas.

PubMed

Ashley, R M; Balmforth, D J; Saul, A J; Blanskby, J D

2005-01-01

Engineering infrastructure is provided at high cost and is expected to have a useful operational life of decades. However, it is clear that the future is uncertain. Traditional approaches to designing and operating urban storm drainage assets have relied on past performance of natural systems and the ability to extrapolate this performance, together with that of the assets across the usable lifetime. Whether or not climate change is going to significantly alter future weather patterns in Europe, it is clear that it is now incumbent on designers and operators of storm drainage systems to prepare for greater uncertainty in the effectiveness of storm drainage systems. A recent U.K. Government study considered the potential effects of climate and socio-economic change in the U.K. in terms of four future scenarios and what the implications are for the performance of existing storm drainage facilities. In this paper the modelling that was undertaken to try to quantify the changes in risk, together with the effectiveness of responses in managing that risk, are described. It shows that flood risks may increase by a factor of almost 30 times and that traditional engineering measures alone are unlikely to be able to provide protection.

Occurrence of pharmaceuticals in Taiwan's surface waters: impact of waste streams from hospitals and pharmaceutical production facilities.

PubMed

Lin, Angela Yu-Chen; Tsai, Yu-Ting

2009-06-01

We investigated the occurrence and distribution of pharmaceuticals (including antibiotics, estrogens, non-steroidal anti-inflammatory drugs (NSAIDs), beta-blockers, and lipid regulators) in three rivers and in the waste streams of six hospitals and four pharmaceutical production facilities in Taiwan. The most frequently detected pharmaceuticals were acetaminophen, erythromycin-H(2)O, sulfamethoxazole, and gemfibrozil. NSAIDs were the next most-often detected compounds, with a detection frequency >60%. The other analytes were not detected or were seen in only a few samples at trace concentrations. The present study demonstrates a significant discharge of human medications from hospital and drug production facilities into surface waters in the Taipei district. The high concentrations of pharmaceuticals found in the Sindian and Dahan rivers demonstrate the alarming degree to which they have been impacted by urban drainage (waste effluents from hospitals, households, and pharmaceutical production facilities). The ubiquitous occurrence at extremely high concentrations of acetaminophen and erythromycin-H(2)O in both rivers (up to 15.7 and 75.5 microg/L) and in wastewater from hospitals and pharmaceutical production facilities (up to 417.5 and 7.84 microg/L) was unique. This finding, in combination with acetaminophen's status as the drug most often prescribed by Taiwan's dominant clinical institute, suggests the potential use of acetaminophen as a molecular indicator of contamination of Taiwan's aqueous environments with untreated urban drainage.

A study of the effect of controlled drainage on surface runoff

USDA-ARS?s Scientific Manuscript database

There is uncertainty about the impact of drainage water management (DWM) on surface runoff, and concern that DWM may increase runoff. To examine this concern, water was applied by sprinkler irrigation to 8 plots which were individually equipped with instrumentation to measure both surface and subsur...

A new automated passive capillary lysimeter for logging real-time drainage water fluxes

USDA-ARS?s Scientific Manuscript database

Effective monitoring of chemical transport through the soil profile requires accurate and appropriate instrumentation to measure drainage water fluxes below the root zone of cropping system. The objectives of this study were to methodically describe in detail the construction and installation of a n...

14 CFR 25.1187 - Drainage and ventilation of fire zones.

Code of Federal Regulations, 2014 CFR

2014-01-01

... component containing flammable fluids. The drainage means must be— (1) Effective under conditions expected... flammable vapors. (c) No ventilation opening may be where it would allow the entry of flammable fluids... vapors will cause an additional fire hazard. (e) Unless the extinguishing agent capacity and rate of...

14 CFR 29.1187 - Drainage and ventilation of fire zones.

Code of Federal Regulations, 2012 CFR

2012-01-01

... component containing flammable fluids. The drainage means must be— (1) Effective under conditions expected... flammable vapors. (c) No ventilation opening may be where it would allow the entry of flammable fluids... section of the powerplant compartment) unless the amount of extinguishing agent and the rate of discharge...

14 CFR 25.1187 - Drainage and ventilation of fire zones.

Code of Federal Regulations, 2010 CFR

2010-01-01

... component containing flammable fluids. The drainage means must be— (1) Effective under conditions expected... flammable vapors. (c) No ventilation opening may be where it would allow the entry of flammable fluids... vapors will cause an additional fire hazard. (e) Unless the extinguishing agent capacity and rate of...

14 CFR 25.1187 - Drainage and ventilation of fire zones.

Code of Federal Regulations, 2013 CFR

2013-01-01

... component containing flammable fluids. The drainage means must be— (1) Effective under conditions expected... flammable vapors. (c) No ventilation opening may be where it would allow the entry of flammable fluids... vapors will cause an additional fire hazard. (e) Unless the extinguishing agent capacity and rate of...

14 CFR 29.1187 - Drainage and ventilation of fire zones.

Code of Federal Regulations, 2010 CFR

2010-01-01

... component containing flammable fluids. The drainage means must be— (1) Effective under conditions expected... flammable vapors. (c) No ventilation opening may be where it would allow the entry of flammable fluids... section of the powerplant compartment) unless the amount of extinguishing agent and the rate of discharge...

14 CFR 29.1187 - Drainage and ventilation of fire zones.

Code of Federal Regulations, 2011 CFR

2011-01-01

... component containing flammable fluids. The drainage means must be— (1) Effective under conditions expected... flammable vapors. (c) No ventilation opening may be where it would allow the entry of flammable fluids... section of the powerplant compartment) unless the amount of extinguishing agent and the rate of discharge...

14 CFR 29.1187 - Drainage and ventilation of fire zones.

Code of Federal Regulations, 2013 CFR

2013-01-01

... component containing flammable fluids. The drainage means must be— (1) Effective under conditions expected... flammable vapors. (c) No ventilation opening may be where it would allow the entry of flammable fluids... section of the powerplant compartment) unless the amount of extinguishing agent and the rate of discharge...

14 CFR 29.1187 - Drainage and ventilation of fire zones.

Code of Federal Regulations, 2014 CFR

2014-01-01

... component containing flammable fluids. The drainage means must be— (1) Effective under conditions expected... flammable vapors. (c) No ventilation opening may be where it would allow the entry of flammable fluids... section of the powerplant compartment) unless the amount of extinguishing agent and the rate of discharge...

14 CFR 25.1187 - Drainage and ventilation of fire zones.

Code of Federal Regulations, 2011 CFR

2011-01-01

... component containing flammable fluids. The drainage means must be— (1) Effective under conditions expected... flammable vapors. (c) No ventilation opening may be where it would allow the entry of flammable fluids... vapors will cause an additional fire hazard. (e) Unless the extinguishing agent capacity and rate of...

14 CFR 25.1187 - Drainage and ventilation of fire zones.

Code of Federal Regulations, 2012 CFR

2012-01-01

... component containing flammable fluids. The drainage means must be— (1) Effective under conditions expected... flammable vapors. (c) No ventilation opening may be where it would allow the entry of flammable fluids... vapors will cause an additional fire hazard. (e) Unless the extinguishing agent capacity and rate of...

Free drainage of aqueous foams: Container shape effects on capillarity and vertical gradients

NASA Astrophysics Data System (ADS)

Saint-Jalmes, A.; Vera, M. U.; Durian, D. J.

2000-06-01

The standard drainage equation applies only to foam columns of constant cross-sectional area. Here, we generalize to include the effects of arbitrary container shape and develop an exact solution for an exponential, "Eiffel Tower", sample. This geometry largely eliminates vertical wetness gradients, and hence capillary effects, and should permit a clean test of dissipation mechanisms. Agreement with experiment is not achieved at late times, however, highlighting the importance of both boundary conditions and coarsening.

Integrated assessment of urban drainage system under the framework of uncertainty analysis.

PubMed

Dong, X; Chen, J; Zeng, S; Zhao, D

2008-01-01

Due to a rapid urbanization as well as the presence of large number of aging urban infrastructures in China, the urban drainage system is facing a dual pressure of construction and renovation nationwide. This leads to the need for an integrated assessment when an urban drainage system is under planning or re-design. In this paper, an integrated assessment methodology is proposed based upon the approaches of analytic hierarchy process (AHP), uncertainty analysis, mathematical simulation of urban drainage system and fuzzy assessment. To illustrate this methodology, a case study in Shenzhen City of south China has been implemented to evaluate and compare two different urban drainage system renovation plans, i.e., the distributed plan and the centralized plan. By comparing their water quality impacts, ecological impacts, technological feasibility and economic costs, the integrated performance of the distributed plan is found to be both better and robust. The proposed methodology is also found to be both effective and practical. (c) IWA Publishing 2008.

Runway drainage characteristics related to tire friction performance

NASA Technical Reports Server (NTRS)

Yager, Thomas J.

1991-01-01

The capability of a runway pavement to rapidly drain water buildup during periods of precipitation is crucial to minimize tire hydroplaning potential and maintain adequate aircraft ground operational safety. Test results from instrumented aircraft, ground friction measuring vehicles, and NASA Langley's Aircraft Landing Dynamics Facility (ALDF) track have been summarized to indicate the adverse effects of pavement wetness conditions on tire friction performance. Water drainage measurements under a range of rainfall rates have been evaluated for several different runway surface treatments including the transversely grooved and longitudinally grinded concrete surfaces at the Space Shuttle Landing Facility (SLF) runway at NASA Kennedy Space Center in Florida. The major parameters influencing drainage rates and extent of flooding/drying conditions are identified. Existing drainage test data are compared to a previously derived empirical relationship and the need for some modification is indicated. The scope of future NASA Langley research directed toward improving empirical relationships to properly define runway drainage capability and consequently, enhance aircraft ground operational safety, is given.

Estimating abundance of mountain lions from unstructured spatial sampling

USGS Publications Warehouse

Russell, Robin E.; Royle, J. Andrew; Desimone, Richard; Schwartz, Michael K.; Edwards, Victoria L.; Pilgrim, Kristy P.; Mckelvey, Kevin S.

2012-01-01

Mountain lions (Puma concolor) are often difficult to monitor because of their low capture probabilities, extensive movements, and large territories. Methods for estimating the abundance of this species are needed to assess population status, determine harvest levels, evaluate the impacts of management actions on populations, and derive conservation and management strategies. Traditional mark–recapture methods do not explicitly account for differences in individual capture probabilities due to the spatial distribution of individuals in relation to survey effort (or trap locations). However, recent advances in the analysis of capture–recapture data have produced methods estimating abundance and density of animals from spatially explicit capture–recapture data that account for heterogeneity in capture probabilities due to the spatial organization of individuals and traps. We adapt recently developed spatial capture–recapture models to estimate density and abundance of mountain lions in western Montana. Volunteers and state agency personnel collected mountain lion DNA samples in portions of the Blackfoot drainage (7,908 km2) in west-central Montana using 2 methods: snow back-tracking mountain lion tracks to collect hair samples and biopsy darting treed mountain lions to obtain tissue samples. Overall, we recorded 72 individual capture events, including captures both with and without tissue sample collection and hair samples resulting in the identification of 50 individual mountain lions (30 females, 19 males, and 1 unknown sex individual). We estimated lion densities from 8 models containing effects of distance, sex, and survey effort on detection probability. Our population density estimates ranged from a minimum of 3.7 mountain lions/100 km2 (95% Cl 2.3–5.7) under the distance only model (including only an effect of distance on detection probability) to 6.7 (95% Cl 3.1–11.0) under the full model (including effects of distance, sex, survey effort, and distance x sex on detection probability). These numbers translate to a total estimate of 293 mountain lions (95% Cl 182–451) to 529 (95% Cl 245–870) within the Blackfoot drainage. Results from the distance model are similar to previous estimates of 3.6 mountain lions/100 km2 for the study area; however, results from all other models indicated greater numbers of mountain lions. Our results indicate that unstructured spatial sampling combined with spatial capture–recapture analysis can be an effective method for estimating large carnivore densities.

Measures for the reduction of sinter formations in tunnels

NASA Astrophysics Data System (ADS)

Harer, Gerhard

2017-09-01

A considerable part of the maintenance costs of tunnel structures is related to the inspection, maintenance and repair of the drainage system. The drainage system of tunnels is frequently clogged with Calcium precipitates. Cleaning and water conditioning are costintensive for operating companies. Apart from the direct costs associated with inspection, maintenance and repair works of the drainage system indirect costs are generated, such as by the blocking of the tunnel while inspection, maintenance or repair or by the reduction of the permitted operation speed. Sintering and clogging of the drainage systems is mainly caused by dissolution of cement minerals in concrete and mortar and/or by inadequate design and construction of the drainage system and/or grubby workmanship. With long-term studies and in-situ experiments in Austria traffic tunnels the specific input factors for sinter mechanism have been identified and appropriate counter measures could be defined. In particular modified mix designs for shotcretes and mortars have proven to bring a significant beneficial effect. By means of constructional measures and by the application of hardness stabilizers a further reduction of hard deposits inside the drainage system is achievable. The paper will deal with the specific aspects and will propose adequate counter measures.

The role of transpapillary drainage in management of patients with pancreatic fluid collections and pancreatic duct disruption as a consequences of severe acute pancreatitis.

PubMed

Jagielski, Mateusz; Smoczyński, Marian; Adrych, Krystian

In last thirty years we have been observing significant development of an endoscopic treatment of pancreatic fluid collections, including transmural drainage of walled-off pancreatic necrosis. Simultaneously, the use of endotherapy in treatment of main pancreatic ducts disruptions has increased. Despite many publications available in current literature, concerning the endoscopic treatment of consequences of acute necrotizing pancreatitis, the role of transpapillary drainage in management of patients with pancreatic fluid collections and pancreatic duct disruption as an after-effect of severe acute pancreatitis remains unclear and is still a current problem. This publication includes comment on the article entitled 'Early dual drainage combining transpapillary endotherapy and percutaneous catheter drainage in patients with pancreatic fistula associated with severe acute pancreatitis' published by Yokoi et al. in the July-August 2016 issue of Pancreatology together with questions to the authors. Furthermore, in the article we did pay particular attention to the role of transpapillary drainage in management of pancreatic fluid collections, especially of walled-of pancreatic necrosis. Copyright © 2016 IAP and EPC. Published by Elsevier B.V. All rights reserved.

Percutaneous drainage in conservative therapy for perforated gastroduodenal ulcers.

PubMed

Oida, Takatsugu; Kano, Hisao; Mimatsu, Kenji; Kawasaki, Atsushi; Kuboi, Youichi; Fukino, Nobutada; Kida, Kazutoshi; Amano, Sadao

2012-01-01

The management of peptic ulcers has dramatically changed and the incidence of elective surgery for gastroduodenal peptic ulcers has markedly decreased; hence, the incidence of emergency surgery for perforated peptic ulcers has slightly increased. In select cases, conservative therapy can be used as an alternative for treating perforated gastroduodenal ulcers. In this study, we evaluated the efficacy of percutaneous abdominal drainage for the conservative treatment of perforated gastroduodenal ulcers. We retrospectively studied 51 patients who had undergone conservative therapy for perforated gastroduodenal ulcers. These patients were divided into 2 groups on the basis of the initial treatment with conservative therapy with or without percutaneous drainage: group PD included patients who had undergone percutaneous drainage and group NPD, patients who had undergone non-percutaneous drainage. In the PD group, 14.3% (n=3) of the patients did not respond to conservative therapy, while this value was 43.3% (n=13) in the NPD group. The 2 groups differed significantly with respect to conversion from conservative therapy to surgery (p<0.0352). Conservative therapy for perforated gastroduodenal ulcers should be performed only in the case of patients meeting the required criteria; its combination with percutaneous intraperitoneal drainage is effective as initial conservative therapy.

Local skull trephination before transfer is associated with favorable outcomes in cerebral herniation from epidural hematoma.

PubMed

Nelson, James A

2011-01-01

The patient with epidural hematoma and cerebral herniation has a good prognosis with immediate drainage, but a poor prognosis with delay to decompression. Such patients who present to nonneurosurgical hospitals are commonly transferred without drainage to the nearest neurosurgical center. This practice has never been demonstrated to be the safest approach to treating these patients. A significant minority of emergency physicians (EPs) have advised and taught bedside burr hole drainage or skull trephination before transfer for herniating patients. The objective of this study was to assess the effect of nonneurosurgeon drainage on neurologic outcome in patients with cerebral herniation from epidural hematoma. A structured literature review was performed using EMBASE, the Cochrane Library, and the Emergency Medicine Abstracts database. No evidence meeting methodologic criteria was found describing outcomes in patients transferred without decompressive procedures. For patients receiving local drainage before transfer, 100% had favorable outcomes. Although the total number of patients is small and the population highly selected, the natural history of cerebral herniation from epidural hematoma and the best available evidence suggests that herniating patients have improved outcomes with drainage procedures before transport. © 2010 by the Society for Academic Emergency Medicine.

Classification scheme for acid rock drainage detection - the Hamersley Basin, Western Australia

NASA Astrophysics Data System (ADS)

Skrzypek, Grzegorz; Dogramaci, Shawan; McLean, Laura

2017-04-01

In arid environment where precipitation and surface water are very limited, groundwater is the most important freshwater resource. For this reasons it is intensively exploited and needs to be managed wisely and protected from pollutants. Acid rock drainage often constitutes a serious risk to groundwater quality, particularly in catchments that are subject to mining, large scale groundwater injection or abstraction. However, assessment of the potential acid rock drainage risk can be challenging, especially in carbonate rich environment, where the decreasing pH that usually accompanies pyrite oxidation, can be masked by the high pH-neutralisation capacity of carbonate minerals. In this study, we analysed 73 surface and groundwater samples from different water bodies and aquifers located in the Hamersley Basin, Western Australia. Although the majority of samples had a neutral pH, there was a large spatial variability in the dissolved sulphate concentrations that ranged from 1 mg/L to 15,000 mg/L. Waters with high dissolved sulphate concentration were found in areas with a high percentage of sulphide minerals (e.g. pyrite) located within the aquifer matrix and were characterised by low δ34SSO4 values (+1.2‰ to +4.6) consistent with signatures of aquifer matrix pyritic rock samples (+1.9‰ to +4.4). It was also found that the SO4 concentrations and acidity levels were not only dependent on δ34SSO4 values and existence of pyrite but also on the presence of carbonate minerals in the aquifer matrix. Based on the results from this study, a classification scheme has been developed for identification of waters impacted by acid rock drainage that also encompasses numerous concomitant geochemical processes that often occur in aqueous systems. The classification uses five proxies: SO4, SO4/Cl, SI of calcite, δ34SSO4 and δ18OSO4 to improve assessment of the contribution that oxidation of sulphide minerals has to overall sulphate ion concentrations, regardless of acidity levels of the aqueous system. This classification scheme enables a more direct monitoring regime for early detection of acid rock drainage processes and better groundwater quality management. References Dogramaci S., McLean L., Skrzypek G., 2017. Hydrochemical and stable isotope indicators of pyrite oxidation in carbonate-rich environment; the Hamersley Basin, Western Australia. Journal of Hydrology 545, 288-298.

Bronchoscopic drainage of a malignant lung abscess.

PubMed

Katsenos, Stamatis; Psathakis, Konstantinos; Chatzivasiloglou, Fotini; Antonogiannaki, Elvira-Markela; Psara, Anthoula; Tsintiris, Konstantinos

2015-04-01

Bronchoscopic drainage of a pyogenic lung abscess is an established therapeutic approach in selected patients in whom conventional antibiotic therapy fails. This intervention has also been undertaken in patients with abscess owing to underlying lung cancer and prior combined radiochemotherapy. However, this procedure has rarely been performed in cavitary lesions of advanced tumor origin before initiating any chemotherapy/radiotherapy scheme. Herein, we describe a case of a 68-year-old woman with lung adenocarcinoma stage IIIB, who underwent bronchoscopic drainage of necrotizing tumor lesion, thus improving her initial poor clinical condition and rendering other treatment modalities, such as radiotherapy, more effective and beneficial. Bronchoscopic drainage of a symptomatic cancerous lung abscess should be considered as an alternative and palliative treatment approach in patients with advanced inoperable non-small cell lung cancer.

Oral (99m)Tc-DTPA simultaneous determination of duodenobiliary reflux and intestinal permeability in patients after choledocholithotomy plus T-tube drainage.

PubMed

Sun, Shao-Long; Wu, Shuo-Dong; Zhang, Xiao-Bo

2005-11-01

The high choledocholithiasis recurrence rate after choledocholithotomy plus T-tube drainage is related to biliary bacterial infection. These bacteria are from the intestine, either via the major duodenal papilla, or the penetrating intestinal mucosa. It is therefore possible that duodenobiliary reflux and increased intestinal permeability exist in patients who have undergone choledocholithotomy. This study was undertaken to find the evidence of duodenobiliary reflux and to assess intestinal permeability in these patients. Twenty-one patients who underwent choledocholithotomy plus T-tube drainage 2 months ago, and 11 healthy volunteers (controls) took orally 185MBq of (99m)Tc-DTPA. The patients' bile was collected in the next 2 hours via a T-tube and the (99m)Tc-DTPA radioactivity in the bile was counted. Intestinal permeability was evaluated by measuring the 24-hour urinary excretion rate of ingested (99m)Tc-DTPA in both patients and controls. In 6 of the 21 patients, radioactivity in the bile was detected. The intestinal permeability was significantly higher in patients (11.45%+/-6.16%) than that in controls (3.61%+/-1.63%, t=3.28, P<0.05). Duodenobiliary reflux exists in patients who have undergone choledocholithotomy plus T-tube drainage. The intestinal permeability is higher in these patients than in healthy subjects. Duodenobiliary reflux and increased intestinal permeability may be factors of cholelithiasis recurrence.

Fine-scale population structure in Atlantic salmon from Maine's Penobscot River drainage

USGS Publications Warehouse

Spidle, A.P.; Bane, Schill W.; Lubinski, B.A.; King, T.L.

2001-01-01

We report a survey of micro satellite DNA variation in Atlantic salmon from the unimpounded lower reaches of Maine's Penobscot River. Our analysis indicates that Atlantic salmon in the Penobscot River are distinct from other populations that have little or no history of human-mediated repopulation, including two of its tributaries, Cove Brook and Kenduskeag Stream, another Maine river, the Ducktrap, and Canada's Miramichi and Gander rivers. Significant heterogeneity was detected in allele frequency among all three subpopulations sampled in the Penobscot drainage. The high resolution of the 12-locus suite was quantified using maximum likelihood assignment tests, which correctly identified the source of 90.4-96.1% of individuals from within the Penobscot drainage. Current populations are clearly isolated from each other, however we are unable to determine from the present data whether the populations in Cove Brook and Kenduskeag Stream are recently diverged from populations stocked into the Penobscot River over the last century, or are aboriginal in origin. The degree of population structure identified in the Penobscot drainage is noteworthy in light of its lengthy history of systematic restocking, the geographic proximity of the subpopulations, and the extent of the differentiation. Similar population structure on this extremely limited geographic scale could exist among Atlantic salmon runs elsewhere in Maine and throughout the species' range and should be taken into account for future management decisions.

Isotopic Identification of Nitrate Sources and Cycling in Arctic Tundra Active Layer Soils and Permafrost

NASA Astrophysics Data System (ADS)

Heikoop, J. M.; Throckmorton, H.; Newman, B. D.; Perkins, G.; Gard, M.; Iversen, C. M.; Wilson, C. J.; Wullschleger, S. D.

2014-12-01

The effect of nitrogen cycling on release of carbon from tundra ecosystems is being studied as part of the US Department of Energy Next Generation Ecosystem Experiment - Arctic project. Sampling and analysis of active layer soil water at the Barrow Environmental Observatory (Alaska, USA) was performed in ancient drained thaw lake basins (DTLBs), drainages, and in polygonal terrain associated with inter-DTLB tundra. Within active layer soils, nitrate was most commonly found above analytical limits of detection in pore water from the unsaturated centers of high-centered polygons. Nitrate has also been detected, though less frequently, in soil water immediately above the frost table of an ancient (14C age of 2000 - 5500 BP) DTLB and in a small drainage adjacent to high-centered polygonal terrain. Nitrate from high-centered polygons had δ15N ranging from -9.2 to +8.5 ‰ and δ18O ranging from -8.4 to +1.4 ‰. The δ15N isotopic range is consistent with microbial mineralization and nitrification of reduced nitrogen sources including ammonium, dissolved organic nitrogen, and soil organic nitrogen. The range in δ18O of nitrate is also consistent with nitrification based on the δ18O of site waters. No evidence for an atmospheric nitrate signal, as defined by δ15N and δ18O of nitrate in snow and snowmelt, is seen. In contrast, nitrate in permafrost appears to be a mixture of pre-industrial atmospheric nitrate (with higher δ15N than modern atmospheric nitrate) and nitrate that is microbial in origin. Massive ice wedges appear to contain larger proportions of snowmelt (based on δ18O of ice) and atmospheric nitrate, whereas textural ice appears to contain a greater proportion of summer precipitation and microbially-derived nitrate. Nitrate from the ancient DTLB and drainage samples also has isotopic signatures that appear to represent a mixture of pre-industrial atmospheric nitrate and nitrate from microbial nitrification, and may, at least in part, be derived from degraded permafrost.

Hydrological inferences through morphometric analysis of lower Kosi river basin of India for water resource management based on remote sensing data

NASA Astrophysics Data System (ADS)

Rai, Praveen Kumar; Chandel, Rajeev Singh; Mishra, Varun Narayan; Singh, Prafull

2018-03-01

Satellite based remote sensing technology has proven to be an effectual tool in analysis of drainage networks, study of surface morphological features and their correlation with groundwater management prospect at basin level. The present study highlights the effectiveness and advantage of remote sensing and GIS-based analysis for quantitative and qualitative assessment of flood plain region of lower Kosi river basin based on morphometric analysis. In this study, ASTER DEM is used to extract the vital hydrological parameters of lower Kosi river basin in ARC GIS software. Morphometric parameters, e.g., stream order, stream length, bifurcation ratio, drainage density, drainage frequency, drainage texture, form factor, circularity ratio, elongation ratio, etc., have been calculated for the Kosi basin and their hydrological inferences were discussed. Most of the morphometric parameters such as bifurcation ratio, drainage density, drainage frequency, drainage texture concluded that basin has good prospect for water management program for various purposes and also generated data base that can provide scientific information for site selection of water-harvesting structures and flood management activities in the basin. Land use land cover (LULC) of the basin were also prepared from Landsat data of 2005, 2010 and 2015 to assess the change in dynamic of the basin and these layers are very noteworthy for further watershed prioritization.

Drainage of pleural effusion in mechanically ventilated patients: time to measure chest wall compliance?

PubMed

Formenti, Paolo; Umbrello, Michele; Piva, Ilaria R; Mistraletti, Giovanni; Zaniboni, Matteo; Spanu, Paolo; Noto, Andrea; Marini, John J; Iapichino, Gaetano

2014-10-01

Pleural effusion (PE) is commonly encountered in mechanically ventilated, critically ill patients and is generally addressed with evacuation or by fluid displacement using increased airway pressure (P(AW)). However, except when massive or infected, clear evidence is lacking to guide its management. The aim of this study was to investigate the effect of recruitment maneuvers and drainage of unilateral PE on respiratory mechanics, gas exchange, and lung volume. Fifteen critically ill and mechanically ventilated patients with unilateral PE were enrolled. A 3-step protocol (baseline, recruitment, and effusion drainage) was applied to patients with more than 400 mL of PE, as estimated by chest ultrasound. Predefined subgroup analysis compared patients with normal vs reduced chest wall compliance (C(CW)). Esophageal and P(AW)s, respiratory system, lung and C(CW)s, arterial blood gases, and end-expiratory lung volumes were recorded. In the whole case mix, neither recruitment nor drainage improved gas exchange, lung volume, or tidal mechanics. When C(CW) was normal, recruitment improved lung compliance (81.9 [64.8-104.1] vs 103.7 [91.5-111.7] mL/cm H2O, P < .05), whereas drainage had no significant effect on total respiratory system mechanics or gas exchange, although it measurably increased lung volume (1717 vs 2150 mL, P < .05). In the setting of reduced C(CW), however, recruitment had no significant effect on total respiratory system mechanics or gas exchange, whereas pleural drainage improved respiratory system and C(CW)s as well as lung volume (42.7 [38.9-50.0] vs 47.0 [43.8-63.3], P < .05 and 97.4 [89.3-97.9] vs 126.7 [92.3-153.8] mL/cm H2O, P < .05 and 1580 vs 1750 mL, P < .05, respectively). Drainage of a moderate-sized effusion should not be routinely performed in unselected population of critically ill patients. We suggest that measurement of C(CW) may help in the decision-making process. Copyright © 2014 Elsevier Inc. All rights reserved.

Glionitrin A, an antibiotic-antitumor metabolite derived from competitive interaction between abandoned mine microbes

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

Park, H.B.; Kown, H.C.; Lee, C.H.

The nutrient conditions present in abandoned coal mine drainages create an extreme environment where defensive and offensive microbial interactions could be critical for survival and fitness. Coculture of a mine drainage-derived Sphingomonas bacterial strain, KMK-001, and a mine drainage-derived Aspergillus fumigatus fungal strain, KMC-901, resulted in isolation of a new diketopiperazine disulfide, glionitrin A (1). Compound 1 was not detected in monoculture broths of KMK-001 or KMC-901. The structure of 1, a (3S,10aS) diketopiperazine disulfide containing a nitro aromatic ring, was based on analysis of MS, NMR, and circular dichroism spectra and confirmed by X-ray crystal data. Glionitrin A displayedmore » significant antibiotic activity against a series of microbes including methicillin-resistant Staphylococcus aureus. An in vitro MTT cytotoxicity assay revealed that 1 had potent submicromolar cytotoxic activity against four human cancer cell lines: HCT-116, A549, AGS, and DU145. The results provide further evidence that microbial coculture can produce novel biologically relevant molecules.« less

[Diagnostic and therapeutic approach to pancreatic trauma].

PubMed

Vidali, Maria; Doulgerakis, George; Condilis, Nicolas; Karmiri, Eleni; Poygouras, Ihon; Papaioannoy, George; Ioannoy, Christos; Pierrakakis, Stefanos; Setakis, Nicolas

2005-01-01

The pancreatic trauma is rare, compared with the injuries of the other abdominal organs and occurs in 0.2-6 per cent of the cases of abdominal trauma. The aim of this essay is to demonstrate the Authors' experience in the treatment of five cases of pancreatic injury during the last five years, as well as to retrospect the contemporary bibliography, connected with the diagnostic and curative approach of the pancreatic trauma. The diagnosis of the pancreatic trauma is difficult and many times, late. In their experience of pancreatic trauma, the Authors ascertained the pancreatic injury during the laparotomy which was made in order to treat other abdominal injuries. The surgical techniques were chosen taking into account the extent of the injury, the detection and the existence of accompanying. Marginal resection of pancreas, splenectomy and drainage were applied to three patients, suture of the pancreas and drainage to one patient, drainage alone and treatment of synchronous rupture of the duodenum to one patient. The mortality was 0%. Came whereas the morbidity came basically on the seriousness of the accompanying injuries.

[Application of trans-abdominal-mediastinal drainage tube in patients with high risk of esophagogastric or esophago-jejunal anastomotic leakage].

PubMed

Wang, Gang-cheng; Han, Guang-sen; Ren, Ying-kun

2012-08-01

To evaluate the therapeutic effects of trans-abdominal-mediastinal drainage tube on the prevention of esophagogastric or esophago-jejunal anastomotic leakage. A total of 79 patients underwent thoraco-abdominal radical resection for gastric cardia cancer, with high risk of leakage of the anatsomosis, from Aug. 2007 to Aug. 2011 were included in this study. They were assigned into 2 groups. Forty one patients had trans-abdominal-mediastinal drainage tube (improvement group) and 38 patients were without the mediastinal drainage tube (control group). The clinical data of all the 79 patients were reviewed and the therapeutic effects of the two treatment approaches were compared. There was anastomotic leakage in four patients of the improvement group. They were with stable vital signs and the median hospital stay was 29.3 days. There was anastomotic leakage in five cases of the contol group and all of them had high fever and chest tightness. One among those five patients had transdermal placement of thoracic drainage tube and was cured, and four among those five patients had second debridement operation, with 3 cured and one death case. Except the one death case, the median hospital stay of the control group was 53.4 days, significantly longer than that of the improvement group (P < 0.05). Although putting trans-abdominal-mediastinal drainage tube can not prevent the leakage of esophagogastric or esophago-jejunnal anastomosis, it can reduce the systemic inflammatory responses, death and painful suffering of the patients caused by anastomotic leakage.

210Pb dating of sediments in a heavily contaminated drainage channel to the La Plata estuary in Buenos Aires, Argentina.

PubMed

Di Gregorio, D E; Fernández Niello, J O; Huck, H; Somacal, H; Curutchet, G

2007-01-01

Concentrations of (210)Pb and (137)Cs in sediment samples collected from two cores at a drainage channel to the La Plata river estuary in Buenos Aires, Argentina, were measured using ultralow-background detection systems. The (210)Pb data were used to determine the rate of sediment accumulation of the sites. These results were correlated with some heavy metal (chromium and lead) concentrations of the samples in an attempt to characterize the historical input of contaminants due to the industrial development, which has taken place in this area over the last century. The (137)Cs measurements demonstrate that cesium dating is not adequate in regions of the southern hemisphere.

Near surface IP investigations: Four case studies

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

Hearst, R.B.; Morris, W.A.; Clark, M.A.

1995-12-31

The use of the Induced Polarisation (IP) method of geophysical surveying for near surface site investigations is gaining acceptance within the geophysical community. In this study the IP method is evaluated as a tool for the delineation of ground water resources; contamination plume detection in a lateritic horizon; and acid mine drainage leak detection from decommissioned mine tailings. A time domain IP system was selected for this study primarily for the flexibility in the selection and setting of receiver time windows and diagnostic characteristics attributed to submitting the data to Cole-Cole analysis. Analysis of the acquired data in conjunction withmore » available borehole and geological information illustrates the effectiveness and usefulness of the survey method for solving near surface problems. In all of the locations tested, it was found that with a properly designed IP survey it was possible to resolve the target and/or related structures.« less

Attribution of Observed Streamflow Changes in Key British Columbia Drainage Basins

NASA Astrophysics Data System (ADS)

Najafi, Mohammad Reza; Zwiers, Francis W.; Gillett, Nathan P.

2017-11-01

We study the observed decline in summer streamflow in four key river basins in British Columbia (BC), Canada, using a formal detection and attribution (D&A) analysis procedure. Reconstructed and simulated streamflow is generated using the semidistributed variable infiltration capacity hydrologic model, which is driven by 1/16° gridded observations and downscaled climate model data from the Coupled Model Intercomparison Project phase 5 (CMIP5), respectively. The internal variability of the regional hydrologic components using 5100 years of streamflow was simulated using CMIP5 preindustrial control runs. Results show that the observed changes in summer streamflow are inconsistent with simulations representing the responses to natural forcing factors alone, while the response to anthropogenic and natural forcing factors combined is detected in these changes. A two-signal D&A analysis indicates that the effects of anthropogenic (ANT) forcing factors are discernable from natural forcing in BC, albeit with large uncertainties.

Flood Impact Assessment in the Surrounding Area of Suvarnabhumi Airport, Thailand

NASA Astrophysics Data System (ADS)

Tingsanchali, Tawatchai; Eng, D.

2009-03-01

The existence of the Second Bangkok International Airport (SBIA) or the Suvarnabhumi International Airport induces more adverse effect to the flooding situation in its surrounding area. Due to limited drainage capacity, during a heavy storm, flooding in the surrounding area occurs over the area. The objective of the study is to find the most suitable flood control and drainage system that can drain floodwater from the surrounding area of 624 sq. km with minimum flood damages and impact to social and living conditions of the people in the study area. This study involves the application of MIKE FLOOD hydrodynamic model for determining the relative effects of flood control and drainage system in the surrounding area of the airport. The results of the study show that flood damages mostly occur in the central and downstream parts of the study area where drainage is insufficient. Flood depth and duration are main parameters used for the estimation of flood losses. Flood mitigation and management in the surrounding area of SBIA is planned by pumping water of 100 m3/s from Klong Samrong canal inside the study area through the proposed drainage channel to the Gulf of Thailand. The existing dikes along boundaries of the study area can protect water from the outer area to enter into the surrounding area of the airport. Flood simulation shows that a canal with capacity of 100 m3/s and a pumping station at the downstream end of the canal are required to cope with the drainage capacity for the flood of 100 years return period. A flood drainage channel of capacity of 100 m3/s is designed and will be constructed to drain flood from Klong Samrong to the sea. On the other hand, the embankment along the proposed drainage canal project improves traffic flow in the vicinity of the airport. On economic benefit, the project investment cost is Baht 8,410 million. The project benefit cost ratio is 2.12 with the economic internal rate of return of 15.61%. The construction period is 4 years. Environmental and social impacts are investigated and counter measures are proposed to reduce the impacts. The study considers compensating scheme for people who are directly affected by the flood drainage project and those who will lose their lands or their professions. Considerations are also extended to people who are indirectly affected by the project. Institutional framework is recommended to be established to manage flood control and drainage and water resources in the surrounding area of the airport.

Preoperative biliary drainage for periampullary tumors causing obstructive jaundice; DRainage vs. (direct) OPeration (DROP-trial).

PubMed

van der Gaag, Niels A; de Castro, Steve M M; Rauws, Erik A J; Bruno, Marco J; van Eijck, Casper H J; Kuipers, Ernst J; Gerritsen, Josephus J G M; Rutten, Jan-Paul; Greve, Jan Willem; Hesselink, Erik J; Klinkenbijl, Jean H G; Rinkes, Inne H M Borel; Boerma, Djamila; Bonsing, Bert A; van Laarhoven, Cees J; Kubben, Frank J G M; van der Harst, Erwin; Sosef, Meindert N; Bosscha, Koop; de Hingh, Ignace H J T; Th de Wit, Laurens; van Delden, Otto M; Busch, Olivier R C; van Gulik, Thomas M; Bossuyt, Patrick M M; Gouma, Dirk J

2007-03-12

Surgery in patients with obstructive jaundice caused by a periampullary (pancreas, papilla, distal bile duct) tumor is associated with a higher risk of postoperative complications than in non-jaundiced patients. Preoperative biliary drainage was introduced in an attempt to improve the general condition and thus reduce postoperative morbidity and mortality. Early studies showed a reduction in morbidity. However, more recently the focus has shifted towards the negative effects of drainage, such as an increase of infectious complications. Whether biliary drainage should always be performed in jaundiced patients remains controversial. The randomized controlled multicenter DROP-trial (DRainage vs. Operation) was conceived to compare the outcome of a 'preoperative biliary drainage strategy' (standard strategy) with that of an 'early-surgery' strategy, with respect to the incidence of severe complications (primary-outcome measure), hospital stay, number of invasive diagnostic tests, costs, and quality of life. Patients with obstructive jaundice due to a periampullary tumor, eligible for exploration after staging with CT scan, and scheduled to undergo a "curative" resection, will be randomized to either "early surgical treatment" (within one week) or "preoperative biliary drainage" (for 4 weeks) and subsequent surgical treatment (standard treatment). Primary outcome measure is the percentage of severe complications up to 90 days after surgery. The sample size calculation is based on the equivalence design for the primary outcome measure. If equivalence is found, the comparison of the secondary outcomes will be essential in selecting the preferred strategy. Based on a 40% complication rate for early surgical treatment and 48% for preoperative drainage, equivalence is taken to be demonstrated if the percentage of severe complications with early surgical treatment is not more than 10% higher compared to standard treatment: preoperative biliary drainage. Accounting for a 10% dropout, 105 patients are needed in each arm resulting in a study population of 210 (alpha = 0.95, beta = 0.8). The DROP-trial is a randomized controlled multicenter trial that will provide evidence whether or not preoperative biliary drainage is to be performed in patients with obstructive jaundice due to a periampullary tumor.

Sensitivity of drainage efficiency of cranberry fields to edaphic conditions

NASA Astrophysics Data System (ADS)

Periard, Yann; José Gumiere, Silvio; Rousseau, Alain N.; Caron, Jean; Hallema, Dennis W.

2014-05-01

Water management on a cranberry farm requires intelligent irrigation and drainage strategies to sustain strong productivity and minimize environmental impact. For example, to avoid propagation of disease and meet evapotranspiration demand, it is imperative to maintain optimal moisture conditions in the root zone, which depends on an efficient drainage system. However, several drainage problems have been identified in cranberry fields. Most of these drainage problems are due to the presence of a restrictive layer in the soil profile (Gumiere et al., 2014). The objective of this work is to evaluate the effects of a restrictive layer on the drainage efficiency by the bias of a multi-local sensitivity analysis. We have tested the sensitivity of the drainage efficiency to different input parameters set of soil hydraulic properties, geometrical parameters and climatic conditions. Soil water flux dynamic for every input parameters set was simulated with finite element model Hydrus 1D (Simanek et al., 2008). Multi-local sensitivity was calculated with the Gâteaux directional derivatives with the procedure described by Cheviron et al. (2010). Results indicate that drainage efficiency is more sensitive to soil hydraulic properties than geometrical parameters and climatic conditions. Then, the geometrical parameters of the depth are more sensitive than the thickness. The drainage efficiency was very insensitive to the climatic conditions. Understanding the sensitivity of drainage efficiency according to soil hydraulic properties, geometrical and climatic conditions are essential for diagnosis drainage problems. However, it becomes important to identify the mechanisms involved in the genesis of anthropogenic soils cranberry to identify conditions that may lead to the formation of a restrictive layer. References: Cheviron, B., S.J. Gumiere, Y. Le Bissonnais, R. Moussa and D. Raclot. 2010. Sensitivity analysis of distributed erosion models: Framework. Water Resources Research 46: W08508. doi:10.1029/2009WR007950. Gumiere, S.J., J. Lafond, D. W. Hallema, Y. Périard, J. Caron et J. Gallichand. 2014. Mapping soil hydraulic conductivity and matric potential for water management of cranberry: Characterization and spatial interpolation methods. Biosystems Engineering.

Percutaneous transgluteal drainage of pelvic abscesses in interventional radiology: A safe alternative to surgery.

PubMed

Robert, B; Chivot, C; Rebibo, L; Sabbagh, C; Regimbeau, J-M; Yzet, T

2016-02-01

Interventional radiology plays an important role in the management of deep pelvic abscesses. Percutaneous drainage is currently considered as the first-line alternative to surgery. A transgluteal computed tomography (CT)-guided approach allows to access to deep infected collections avoiding many anatomical obstacles (vessels, nerves, bowel, bladder). The objective of this study was to assess the safety and efficacy of a transgluteal approach by reviewing our clinical experience. We reviewed medical records of patients having undergone percutaneous CT-guided transgluteal drainage for deep pelvic abscesses. We focused on the duration of catheter drainage, the complications related to the procedures and the rate of complete resolution. Between 2005 and 2013, 39patients (27women and 12men; mean age: 52.5) underwent transgluteal approach CT-guided percutaneous drainage of pelvis abscesses in our department. The origins of abscesses were postoperative complications in 34patients (87.2%) and infectious intra-abdominal disease in 5patients (12.8%). The mean duration of drainage was 8.3days (range: 3-33). Laboratory cultures were positive in 35patients (89.7%) and Escherichia coli was present in 71.4% of the positive samples. No major complication was observed. Drainage was successful in 38patients (97.4%). A transpiriformis approach was more significantly associated with intra-procedural pain (P=0.003). Percutaneous CT-guided drainage with a transgluteal approach is a safe, well-tolerated and effective alternative to surgery for deep pelvic abscesses. This approach should be considered as the first-line intention for the treatment of deep pelvic abscesses. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

Isotopic mixing model for quantifying contributions of soil water and groundwater in subsurface ('tile') drainage

NASA Astrophysics Data System (ADS)

Kennedy, C. D.; Gall, H.; Jafvert, C. T.; Bowen, G. J.

2010-12-01

Subsurface (‘tile’) drainage, consisting of buried grids of perforated pipe, has provided a means of converting millions of acres of poorly drained soils in the Midwestern U.S. into fertile cropland. However, by altering pathways and rates of soil water and groundwater movement through agricultural lands, this practice may accelerate the loss of nitrate and other agrochemicals. To better understand the hydrological controls on nitrogen dynamics in artificially drained agricultural watersheds, a field sampling program has been established at the Animal Science Research and Education Center (ASREC) at Purdue University (West Lafayette, Indiana) to (1) measure precipitation amount, tile flow, and water-table elevation, and (2) collect water samples for analysis of nitrate, major ions, and oxygen isotope ratios in precipitation, tile drainage, shallow (1 m) and deep (3 m) groundwater, and soil water during storm events. Preliminary physical, chemical, and isotopic data collected at the ASREC show a coincident timing of peak storm ‘event water’ and peak nitrate flux in tile drainage, suggesting significant routing of infiltrating event water. In this work, we aim to refine our understanding of tile drainage at the ASREC by developing a mixing model for partitioning contributions of soil water and groundwater in tile drainage during several storm runoff events ranging in precipitation intensity and coinciding with varying antecedent soil moisture conditions. The results of our model will describe tile drainage in terms of its hydrological components, soil water and groundwater, which in turn will provide a means of incorporating the effects of tile drainage in surface/subsurface hydrological transport models.

Ultrasound-guided thoracenthesis: the V-point as a site for optimal drainage positioning.

PubMed

Zanforlin, A; Gavelli, G; Oboldi, D; Galletti, S

2013-01-01

In the latest years the use of lung ultrasound is increasing in the evaluation of pleural effusions, because it makes follow-up easier and drainage more efficient by providing guidance on the most appropriate sampling site. However, no standardized approach for ultrasound-guided thoracenthesis is actually available. To evaluate our usual ultrasonographic landmark as a possible standard site to perform thoracenthesis by assessing its value in terms of safety and efficiency (success at first attempt, drainage as complete as possible). Hospitalized patients with non organized pleural effusion underwent thoracenthesis after ultrasound evaluation. The point showing on ultrasound the maximum thickness of the effusion ("V-point") was chosen for drainage. 45 ultrasound guided thoracenthesis were performed in 12 months. In 22 cases there were no complications; 16 cases of cough, 2 cases of mild dyspnea without desaturation, 4 cases of mild pain; 2 cases of complications requiring medical intervention occurred. No case of pneumothorax related to the procedure was detected. In all cases drainage was successful on the first attempt. The collected values of maximum thickness at V-point (min 3.4 cm - max 15.3 cm) and drained fluid volume (min 70 ml - max 2000 ml) showed a significative correlation (p < 0.0001). When the thickness was greater or equal to 9.9 cm, drained volume was always more than 1000 ml. The measure of the maximum thickness at V-point provides high efficiency to ultrasound guided thoracentesis and allows to estimate the amount of fluid in the pleural cavity. It is also an easy parameter that makes the proposed method quick to learn and apply.  

Management effects on greenhouse gas dynamics in fen ditches.

PubMed

Peacock, Mike; Ridley, Luke M; Evans, Chris D; Gauci, Vincent

2017-02-01

Globally, large areas of peatland have been drained through the digging of ditches, generally to increase agricultural production. By lowering the water table it is often assumed that drainage reduces landscape-scale emissions of methane (CH 4 ) into the atmosphere to negligible levels. However, drainage ditches themselves are known to be sources of CH 4 and other greenhouse gases (GHGs), but emissions data are scarce, particularly for carbon dioxide (CO 2 ) and nitrous oxide (N 2 O), and show high spatial and temporal variability. Here, we report dissolved GHGs and diffusive fluxes of CH 4 and CO 2 from ditches at three UK lowland fens under different management; semi-natural fen, cropland, and cropland restored to low-intensity grassland. Ditches at all three fens emitted GHGs to the atmosphere, but both fluxes and dissolved GHGs showed extensive variation both seasonally and within-site. CH 4 fluxes were particularly large, with medians peaking at all three sites in August at 120-230mgm -2 d -1 . Significant between site differences were detected between the cropland and the other two sites for CO 2 flux and all three dissolved GHGs, suggesting that intensive agriculture has major effects on ditch biogeochemistry. Multiple regression models using environmental and water chemistry data were able to explain 29-59% of observed variation in dissolved GHGs. Annual CH 4 fluxes from the ditches were 37.8, 18.3 and 27.2gCH 4 m -2 yr -1 for the semi-natural, grassland and cropland, and annual CO 2 fluxes were similar (1100 to 1440gCO 2 m -2 yr -1 ) among sites. We suggest that fen ditches are important contributors to landscape-scale GHG emissions, particularly for CH 4 . Ditch emissions should be included in GHG budgets of human modified fens, particularly where drainage has removed the original terrestrial CH 4 source, e.g. agricultural peatlands. Copyright © 2016 Elsevier B.V. All rights reserved.

Effectiveness of oat and rye cover crops in reducing nitrate losses in drainage water

USDA-ARS?s Scientific Manuscript database

A significant portion of the NO3 from agricultural fields that contaminates surface waters in the Midwest Corn Belt is transported to streams or rivers by subsurface drainage systems or “tiles”. Previous research has shown that N fertilizer management alone is not sufficient for reducing NO3 concent...

Effects of subsurface drainage systems on water and nitrogen footprints simulated with RZWQM2

USDA-ARS?s Scientific Manuscript database

When considering the use of drainage water management (DWM) in the Midwest to reduce nutrient contributions to the Northern Gulf of Mexico Hypoxic Zone, it is essential to understand the long-term performance of these systems. Few studies have evaluated long-term impacts of DWM and the simulation of...

Cold air drainage flows subsidize montane valley ecosystem productivity

Treesearch

Kimberly A. Novick; Andrew C. Oishi; Chelcy Ford Miniat

2016-01-01

In mountainous areas, cold air drainage from high to low elevations has pronounced effects on local temperature, which is a critical driver of many ecosystem processes, including carbon uptake and storage. Here, we leverage new approaches for interpreting ecosystem carbon flux observations in complex terrain to quantify the links between macro-climate...

Effects of Land Use of the Hydrology of Drained Coastal Plain Watersheds

Treesearch

R. Wayne Skaggs; George M Chescheir; Glen P. Fernandez; Devendra M. Amatya

2004-01-01

Some of the world's most productive cropland requires artificial or improved drainage for efficient agricultural production. Soil hydraulic properties, such as hydraulicconductivity and drainable porosity, are conventionally used in design of drainage systems. While it is recognized that these soil properties vary over a relatively wide range within a given soil...

Effect of alternative surface inlet designs on sediment and phosphorus drainage losses

USDA-ARS?s Scientific Manuscript database

Open surface inlets that connect to subsurface tile drainage systems provide a direct pathway for sediment, nutrients, and agrochemicals to surface waters. This study was conducted to determine whether modifying open inlets by burying them in gravel capped with 30 cm of sandy clay loam soil or in ve...

The management of vacuum neck drains in head and neck surgery and the comparison of two different practice protocols for drain removal.

PubMed

Kasbekar, A V; Davies, F; Upile, N; Ho, M W; Roland, N J

2016-01-01

Introduction The management of vacuum neck drains in head and neck surgery is varied. We aimed to improve early drain removal and therefore patient discharge in a safe and effective manner. Methods The postoperative management of head and neck surgical patients with vacuum neck drains was reviewed retrospectively. A new policy was then implemented to measure drainage three times daily (midnight, 6am, midday). The decision for drain removal was based on the most recent drainage period (at <3ml per hour). A further patient cohort was subsequently assessed prospectively. The length of hospital stay was compared between the cohorts. Results The retrospective audit included 51 patients while the prospective audit included 47. The latter saw 16 patients (33%) discharged at least one day earlier than they would have been under the previous policy. No adverse effects were noted from earlier drain removal. Conclusions Measuring drainage volumes three times daily allows for more accurate assessment of wound drainage, and this can lead to earlier removal of neck drains and safe discharge.

Preliminary appraisal of the geohydrologic aspects of drainage wells, Orlando area, central Florida

USGS Publications Warehouse

Kimrey, Joel O.

1978-01-01

The Floridan aquifer contains two highly transmissive cavernous zones in the Orlando area: an upper producing zone about 150-600 feet below land surface; and a lower producing zone about 1,100-1,500 feet below land surface. Natural head differences are downward and there is hydraulic connection between the two producing zones. Drainage wells are finished open-end into the upper producing zone and emplace surface waters directly into that zone by gravity. Quantitatively, their use constitutes an effective method of artificial recharge. Their negative aspects relate to the probably poor, but unknown, quality of the recharge water. Caution is suggested in drawing definite and final conclusions on the overall geohydrologic and environmental effects of drainage wells prior to the collection and interpretation of a considerable quantity of new data. Though few ground-water pollution problems have been documented to date, the potential for such pollution should be seriously considered in light of the prob-able continuing need to use drainage wells; the probable volumes and quality of water involved; and the hydraulic relations between the two producing zones.

Channelized subglacial drainage over a deformable bed

USGS Publications Warehouse

Walder, J.S.; Fowler, A.

1994-01-01

We develop theoretically a description of a possible subglacial drainage mechanism for glaciers and ice sheets moving over saturated, deformable till. The model is based on the plausible assumption that flow of water in a thin film at the ice-till interface is unstable to the formation of a channelized drainage system, and is restricted to the case in which meltwater cannot escape through the till to an underlying aquifer. In describing the physics of such channelized drainage, we have generalized and extended Rothlisberger's model of channels cut into basal ice to include "canals' cut into the till, paying particular attention to the role of sediment properties and the mechanics of sediment transport. We show that sediment-floored Rothlisberger (R) channels can exist for high effective pressures, and wide, shallow, ice-roofed canals cut into the till for low effective pressures. Canals should form a distributed, non-arborescent system, unlike R channels. Geologic evidence derived from land forms and deposits left by the Pleistocene ice sheets in North America and Europe is consistent with predictions of the model. -from Authors

Effect of regional slope on drainage networks

NASA Astrophysics Data System (ADS)

Phillips, Loren F.; Schumm, S. A.

1987-09-01

Drainage networks that develop under conditions of no structural control and homogeneous lithology are generally dendritic, depending upon the shape and inclination of the surface on which they form. An experimental study was designed to investigate the effect of an increase of slope on the evolution and development of dendritic drainage patterns. As slope steepens, the pattern changes from dendritic at 1% slope, to subdendritic at 2%, to subparallel at 3%, to parallel at 5% and higher. The change from a dendritic-type pattern to a parallel-type pattern occurs at a low slope, between 2% and 3%, and primary channel junction angles decrease abruptly from about 60° to 43°. *Present address: U.S. Army Environmental Hygiene Agency, Attn: HSHB-ME-WM, Aberdeen Proving Ground, Maryland 21010-5422

Remedial Investigation/Feasibility Study, Operable Unit 5, Elmendorf AFB, Anchorage, Alaska. Volume 1. Text

DTIC Science & Technology

1994-03-04

4.7a Organic Con mnats Detected in Upper Aquifer Groundwater .......... 4-46 4.7b Organic Contaminants Detected in Upper Aquifer Groundwater...OU 5 con ~tamiats and impacts on Ship Creek; "* Deftrmine fth fluenc of uppadient contminant sources on fth OU 5 "* Collect suifficient data to detemin...Post Rood, mnorh of the gdof course pro shop, and flowed into a drainage ditch parallel to Post Road. 0 All six source areas have undergone previous inv

A conceptual model for the development of pristine drainage systems during exhumation of metamorphic core complexes

NASA Astrophysics Data System (ADS)

Trost, Georg; Neubauer, Franz; Robl, Jörg

2017-04-01

Metamorphic core complexes (MCCs) are defined as large scale geological features of domal shape. The essential characteristic comprises metamorphic rocks, which have been exhumed from lower crustal levels and now are exposed to the surface. The updoming process occurs at different tectonic settings of high strain zones initially exposing pristine gently dipping fault planes to Earth's surface. Consequently, the dome shape highly influences the type of adaption of the drainage systems to the active landforms. However, drainage systems and their characteristic metrics in regions shaped by MCCs have only been sparsely investigated and were not examined regarding the distinction between different MCC-types (A-type, B-type, C-type). In this study we investigate the drainage patterns of MCCs formed by different tectonic settings and build up a conceptual model for the development of the drainage systems under these conditions. We apply the χ-method to detect variations in uplift, as well as spatial unconformities in the drainage patterns. The χ-method is a mathematical approach to transform stream longitudinal profiles to the χ space where the slope of steady state profiles is solely dependent on uplift rate and bedrock erodibility. From this transformation we calculate color-coded χ-maps and χ-profiles of the main streams draining the MCCs. The applied method allows the interpretation of channel metrics in terms of (a) spatial gradients in uplift rate and (b) the time dependent evolution of drainage divides including drainage divide migration. Our results show a high variation in the shape and greatest elevation of the χ-profiles. This indicates the migration of active uplift zones along the dome axes. Even though only MCCs younger than Miocene age are investigated, the shape of the χ-profiles clearly points to different development stages of these areas. K-profiles plotted over the detachment underlying an active updoming process show concave shaped χ-profiles. In contrast, χ-profiles plotted over the detachments coined by long-term erosional processes tend to preserve prominent knickpoints in linearly proceeding profiles. Additionally, the migration of the watersheds indicates lateral extension of the domes, potentially influenced by rolling hinges. MCCs subjected to active uplift show proceeding stream piracy of streams following tectonically induced lineaments. Drainage systems have systematically deflected streams at the edges of the dome structures. The deflections can be especially observed at A-type domes (dome axis oriented parallel to the direction of extension). We conclude that our observations can be explained by the Rolling-Hinge model for MCC-formation. This model is applicable for all types of MCCs and gives the mechanical basis for the updoming process and such for the first stages of drainage development. Some of the observed features are dedicated to ongoing erosional processes and hence represent later phases of MCC development.

High-frequency monitoring of water fluxes and nutrient loads to assess the effects of controlled drainage on water storage and nutrient transport

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

Rozemeijer, J. C.; Visser, A.; Borren, W.

High nitrogen (N) and phosphorus (P) fluxes from upstream agriculture threaten aquatic ecosystems in surface waters and estuaries, especially in areas characterized by high agricultural N and P inputs and densely drained catchments like the Netherlands. Controlled drainage has been recognized as an effective option to optimize soil moisture conditions for agriculture and to reduce unnecessary losses of fresh water and nutrients. This is achieved by introducing control structures with adjustable overflow levels into subsurface tube drain systems. A small-scale (1 ha) field experiment was designed to investigate the hydrological and chemical changes after introducing controlled drainage. Precipitation rates andmore » the response of water tables and drain fluxes were measured in the periods before the introduction of controlled drainage (2007–2008) and after (2009–2011). For the N and P concentration measurements, auto-analyzers for continuous records were combined with passive samplers for time-averaged concentrations at individual drain outlets. The experimental setup enabled the quantification of changes in the water and solute balance after introducing controlled drainage. The results showed that introducing controlled drainage reduced the drain discharge and increased the groundwater storage in the field. To achieve this, the overflow levels have to be elevated in early spring, before the drain discharge stops due to dryer conditions and falling groundwater levels. The groundwater storage in the field would have been larger if the water levels in the adjacent ditch were controlled as well by an adjustable weir. The N concentrations and loads increased, which was largely related to elevated concentrations in one of the three monitored tube drains. The P loads via the tube drains reduced due to the reduction in discharge after introducing controlled drainage. Furthermore, this may be counteracted by the higher groundwater levels and the larger contribution of N- and P-rich shallow groundwater and overland flow to the surface water.« less

High-frequency monitoring of water fluxes and nutrient loads to assess the effects of controlled drainage on water storage and nutrient transport

DOE PAGES

Rozemeijer, J. C.; Visser, A.; Borren, W.; ...

2016-01-19

High nitrogen (N) and phosphorus (P) fluxes from upstream agriculture threaten aquatic ecosystems in surface waters and estuaries, especially in areas characterized by high agricultural N and P inputs and densely drained catchments like the Netherlands. Controlled drainage has been recognized as an effective option to optimize soil moisture conditions for agriculture and to reduce unnecessary losses of fresh water and nutrients. This is achieved by introducing control structures with adjustable overflow levels into subsurface tube drain systems. A small-scale (1 ha) field experiment was designed to investigate the hydrological and chemical changes after introducing controlled drainage. Precipitation rates andmore » the response of water tables and drain fluxes were measured in the periods before the introduction of controlled drainage (2007–2008) and after (2009–2011). For the N and P concentration measurements, auto-analyzers for continuous records were combined with passive samplers for time-averaged concentrations at individual drain outlets. The experimental setup enabled the quantification of changes in the water and solute balance after introducing controlled drainage. The results showed that introducing controlled drainage reduced the drain discharge and increased the groundwater storage in the field. To achieve this, the overflow levels have to be elevated in early spring, before the drain discharge stops due to dryer conditions and falling groundwater levels. The groundwater storage in the field would have been larger if the water levels in the adjacent ditch were controlled as well by an adjustable weir. The N concentrations and loads increased, which was largely related to elevated concentrations in one of the three monitored tube drains. The P loads via the tube drains reduced due to the reduction in discharge after introducing controlled drainage. Furthermore, this may be counteracted by the higher groundwater levels and the larger contribution of N- and P-rich shallow groundwater and overland flow to the surface water.« less

Subglottic secretion drainage for the prevention of ventilator-associated pneumonia: a systematic review and meta-analysis.

PubMed

Muscedere, John; Rewa, Oleksa; McKechnie, Kyle; Jiang, Xuran; Laporta, Denny; Heyland, Daren K

2011-08-01

Aspiration of secretions containing bacterial pathogens into the lower respiratory tract is the main cause of ventilator-associated pneumonia. Endotracheal tubes with subglottic secretion drainage can potentially reduce this and, therefore, the incidence of ventilator-associated pneumonia. New evidence on subglottic secretion drainage as a preventive measure for ventilator-associated pneumonia has been recently published and to consider the evidence in totality, we conducted an updated systematic review and meta-analysis. We searched computerized databases, reference lists, and personal files. We included randomized clinical trials of mechanically ventilated patients comparing standard endotracheal tubes to those with subglottic secretion drainage and reporting on the occurrence of ventilator-associated pneumonia. Studies were meta-analyzed for the primary outcome of ventilator-associated pneumonia and secondary clinical outcomes. We identified 13 randomized clinical trials that met the inclusion criteria with a total of 2442 randomized patients. Of the 13 studies, 12 reported a reduction in ventilator-associated pneumonia rates in the subglottic secretion drainage arm; in meta-analysis, the overall risk ratio for ventilator-associated pneumonia was 0.55 (95% confidence interval, 0.46-0.66; p < .00001) with no heterogeneity (I = 0%). The use of subglottic secretion drainage was associated with reduced intensive care unit length of stay (-1.52 days; 95% confidence interval, -2.94 to -0.11; p = .03); decreased duration of mechanically ventilated (-1.08 days; 95% confidence interval, -2.04 to -0.12; p = .03), and increased time to first episode of ventilator-associated pneumonia (2.66 days; 95% confidence interval, 1.06-4.26; p = .001). There was no effect on adverse events or on hospital or intensive care unit mortality. In those at risk for ventilator-associated pneumonia, the use of endotracheal tubes with subglottic secretion drainage is effective for the prevention of ventilator-associated pneumonia and may be associated with reduced duration of mechanical ventilation and intensive care unit length of stay.

EUS-guided drainage of pancreatic fluid collections using a novel lumen-apposing metal stent on an electrocautery-enhanced delivery system: a large retrospective study (with video).

PubMed

Rinninella, Emanuele; Kunda, Rastislav; Dollhopf, Markus; Sanchez-Yague, Andres; Will, Uwe; Tarantino, Ilaria; Gornals Soler, Joan; Ullrich, Sebastian; Meining, Alexander; Esteban, Josè Miguel; Enz, Thomas; Vanbiervliet, Geoffroy; Vleggaar, Frank; Attili, Fabia; Larghi, Alberto

2015-12-01

A lumen-apposing, self-expanding metal stent incorporated in an electrocautery-enhanced delivery system for EUS-guided drainage of pancreatic fluid collections (PFCs) recently has become available. The aim of this study was to analyze the safety and clinical effectiveness of this newly developed device in this clinical setting. This was a retrospective analysis of all consecutive patients with PFCs who underwent EUS-guided drainage using the study device in 13 European centers. Ninety-three patients with PFCs (80% with complex collections) underwent drainage using the study device. Penetration of the PFC was accomplished directly with the study device in 74.2% of patients, and successful stent placement was accomplished in all but 1 patient, mostly without fluoroscopic assistance. Direct endoscopic necrosectomy (DEN) was carried out in 31 of 52 cases (59.6%) of walled-off necrosis and in 2 of 4 cases (50%) of acute peripancreatic fluid collection. Complete resolution of the PFC was obtained in 86 cases (92.5%), with no recurrence during follow-up. Treatment failure occurred in 6 patients because of persistent infection requiring surgery (n = 3), perforation and massive bleeding caused by the nasocystic drainage catheter (NCDC) (n = 2), and the need for a larger opening to extract large necrotic tissue pieces (n = 1). Major adverse events occurred in 5 patients (perforation and massive bleeding caused by the NCDC in 2 patients, 1 pneumoperitoneum and 1 stent dislodgement during DEN, and 1 postdrainage infection) and were mostly not related to the drainage procedure. EUS-guided drainage with the electrocautery-enhanced delivery system is a safe, easy to perform, and a highly effective minimally invasive treatment modality for PFCs. Copyright © 2015 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.

High-frequency monitoring of water fluxes and nutrient loads to assess the effects of controlled drainage on water storage and nutrient transport

NASA Astrophysics Data System (ADS)

Rozemeijer, J. C.; Visser, A.; Borren, W.; Winegram, M.; van der Velde, Y.; Klein, J.; Broers, H. P.

2016-01-01

High nitrogen (N) and phosphorus (P) fluxes from upstream agriculture threaten aquatic ecosystems in surface waters and estuaries, especially in areas characterized by high agricultural N and P inputs and densely drained catchments like the Netherlands. Controlled drainage has been recognized as an effective option to optimize soil moisture conditions for agriculture and to reduce unnecessary losses of fresh water and nutrients. This is achieved by introducing control structures with adjustable overflow levels into subsurface tube drain systems. A small-scale (1 ha) field experiment was designed to investigate the hydrological and chemical changes after introducing controlled drainage. Precipitation rates and the response of water tables and drain fluxes were measured in the periods before the introduction of controlled drainage (2007-2008) and after (2009-2011). For the N and P concentration measurements, auto-analyzers for continuous records were combined with passive samplers for time-averaged concentrations at individual drain outlets. The experimental setup enabled the quantification of changes in the water and solute balance after introducing controlled drainage. The results showed that introducing controlled drainage reduced the drain discharge and increased the groundwater storage in the field. To achieve this, the overflow levels have to be elevated in early spring, before the drain discharge stops due to dryer conditions and falling groundwater levels. The groundwater storage in the field would have been larger if the water levels in the adjacent ditch were controlled as well by an adjustable weir. The N concentrations and loads increased, which was largely related to elevated concentrations in one of the three monitored tube drains. The P loads via the tube drains reduced due to the reduction in discharge after introducing controlled drainage. However, this may be counteracted by the higher groundwater levels and the larger contribution of N- and P-rich shallow groundwater and overland flow to the surface water.

Managing tile drainage, subirrigation, and nitrogen fertilization to enhance crop yields and reduce nitrate loss.

PubMed

Drury, C F; Tan, C S; Reynolds, W D; Welacky, T W; Oloya, T O; Gaynor, J D

2009-01-01

Improving field-crop use of fertilizer nitrogen is essential for protecting water quality and increasing crop yields. The objective of this study was to determine the effectiveness of controlled tile drainage (CD) and controlled tile drainage with subsurface irrigation (CDS) for mitigating off-field nitrate losses and enhancing crop yields. The CD and CDS systems were compared on a clay loam soil to traditional unrestricted tile drainage (UTD) under a corn (Zea Mays L.)-soybean (Glycine Max. (L.) Merr.) rotation at two nitrogen (N) fertilization rates (N1: 150 kg N ha(-1) applied to corn, no N applied to soybean; N2: 200 kg N ha(-1) applied to corn, 50 kg N ha(-1) applied to soybean). The N concentrations in tile flow events with the UTD treatment exceeded the provisional long-term aquatic life limit (LT-ALL) for freshwater (4.7 mg N L(-1)) 72% of the time at the N1 rate and 78% at the N2 rate, whereas only 24% of tile flow events at N1 and 40% at N2 exceeded the LT-ALL for the CDS treatment. Exceedances in N concentration for surface runoff and tile drainage were greater during the growing season than the non-growing season. At the N1 rate, CD and CDS reduced average annual N losses via tile drainage by 44 and 66%, respectively, relative to UTD. At the N2 rate, the average annual decreases in N loss were 31 and 68%, respectively. Crop yields from CDS were increased by an average of 2.8% relative to UTD at the N2 rate but were reduced by an average of 6.5% at the N1 rate. Hence, CD and CDS were effective for reducing average nitrate losses in tile drainage, but CDS increased average crop yields only when additional N fertilizer was applied.

46 CFR 154.350 - Bilge and ballast systems in the cargo area.

Code of Federal Regulations, 2010 CFR

2010-10-01

..., and insulation spaces must have a means of sounding the space or other means of detecting liquid leakage specially approved by the Commandant (CG-522). (b) Each hold and insulation space must have a bilge drainage system. (c) Interbarrier spaces must have an eductor or pump for removing liquid cargo...

46 CFR 154.350 - Bilge and ballast systems in the cargo area.

Code of Federal Regulations, 2011 CFR

2011-10-01

..., and insulation spaces must have a means of sounding the space or other means of detecting liquid leakage specially approved by the Commandant (CG-522). (b) Each hold and insulation space must have a bilge drainage system. (c) Interbarrier spaces must have an eductor or pump for removing liquid cargo...

46 CFR 154.350 - Bilge and ballast systems in the cargo area.

Code of Federal Regulations, 2012 CFR

2012-10-01

..., and insulation spaces must have a means of sounding the space or other means of detecting liquid leakage specially approved by the Commandant (CG-ENG). (b) Each hold and insulation space must have a bilge drainage system. (c) Interbarrier spaces must have an eductor or pump for removing liquid cargo...

46 CFR 154.350 - Bilge and ballast systems in the cargo area.

Code of Federal Regulations, 2013 CFR

2013-10-01

..., and insulation spaces must have a means of sounding the space or other means of detecting liquid leakage specially approved by the Commandant (CG-ENG). (b) Each hold and insulation space must have a bilge drainage system. (c) Interbarrier spaces must have an eductor or pump for removing liquid cargo...

46 CFR 154.350 - Bilge and ballast systems in the cargo area.

Code of Federal Regulations, 2014 CFR

2014-10-01

..., and insulation spaces must have a means of sounding the space or other means of detecting liquid leakage specially approved by the Commandant (CG-ENG). (b) Each hold and insulation space must have a bilge drainage system. (c) Interbarrier spaces must have an eductor or pump for removing liquid cargo...

Effectiveness of highway-drainage systems in preventing contamination of ground water by road salt, Route 25, southeastern Massachusetts; description of study area, data collection programs, and methodology

USGS Publications Warehouse

Church, P.E.; Armstrong, D.S.; Granato, G.E.; Stone, V.J.; Smith, K.P.; Provencher, P.L.

1996-01-01

Four test sites along a 7-mile section of Route 25 in southeastern Massachusetts, each representing a specific highway-drainage system, were instrumented to determine the effectiveness of the drainage systems in preventing contamination of ground water by road salt. One of the systems discharges highway runoff onsite through local drainpipes. The other systems use trunkline drainpipes through which runoff from highway surfaces, shoulders, and median strips is diverted and discharged into either a local stream or a coastal waterway. Route 25 was completed and opened to traffic in the summer of 1987. Road salt was first applied to the highway in the winter of 1987-88. The study area is on a thick outwash plain composed primarily of sand and gravel. Water-table depths range from 15 to 60 feet below land surface at the four test sites. Ground-water flow is in a general southerly direction, approximately perpendicular to the highway. Streamflow in the study area is controlled primarily by ground-water discharge. Background concentrations of dissolved chloride, sodium, and calcium-the primary constituents of road salt-are similar in ground water and surface water and range from 5 to 20, 5 to 10, and 1 to 5 milligrams per liter, respectively. Data-collection programs were developed for monitoring the application of road salt to the highway, the quantity of road-salt water entering the ground water, diverted through the highway-drainage systems, and entering a local stream. The Massachusetts Highway Department monitored road salt applied to the highway and reported these data to the U.S. Geological Survey. The U.S. Geological Survey designed and operated the ground-water, highway- drainage, and surface-water data-collection programs. A road-salt budget will be calculated for each test site so that the effectiveness of the different highway-drainage systems in preventing contamination of ground water by road salt can be determined.

Simplified continuous simulation model for investigating effects of controlled drainage on long-term soil moisture dynamics with a shallow groundwater table.

PubMed

Sun, Huaiwei; Tong, Juxiu; Luo, Wenbing; Wang, Xiugui; Yang, Jinzhong

2016-08-01

Accurate modeling of soil water content is required for a reasonable prediction of crop yield and of agrochemical leaching in the field. However, complex mathematical models faced the difficult-to-calibrate parameters and the distinct knowledge between the developers and users. In this study, a deterministic model is presented and is used to investigate the effects of controlled drainage on soil moisture dynamics in a shallow groundwater area. This simplified one-dimensional model is formulated to simulate soil moisture in the field on a daily basis and takes into account only the vertical hydrological processes. A linear assumption is proposed and is used to calculate the capillary rise from the groundwater. The pipe drainage volume is calculated by using a steady-state approximation method and the leakage rate is calculated as a function of soil moisture. The model is successfully calibrated by using field experiment data from four different pipe drainage treatments with several field observations. The model was validated by comparing the simulations with observed soil water content during the experimental seasons. The comparison results demonstrated the robustness and effectiveness of the model in the prediction of average soil moisture values. The input data required to run the model are widely available and can be measured easily in the field. It is observed that controlled drainage results in lower groundwater contribution to the root zone and lower depth of percolation to the groundwater, thus helping in the maintenance of a low level of soil salinity in the root zone.

NASA/MSFC ground-based Doppler lidar nocturnal boundary layer experiment (Noblex)

NASA Technical Reports Server (NTRS)

Emmitt, G. D.

1984-01-01

During the summer of 1982, NASA/MSFC's ground-based CO2 Doppler Lidar Velocimeter (DLV) was deployed at the Denver Stapleton Airport as part of NASA's participation in the JAWS (Joint Airport Weather Studies) program. Configured to measure the radial wind component within a 10 km radius, the conically scanning lidar was used to examine the evolution of a nocturnal boundary layer under the conditions of cloud free skies and rolling terrain. A valley drainage flow was detected and a two dimension flow visualization constructed. The depth of the gravity current was -700 meters while the depth of the creek valley was -150 meters. This deep drainage flow was detectable for distances of 30 to 40 km from the exit region of the valley. Although the sample period (2000 to 2300 CST) was short and only one nocturnal boundary layer case examined, the usefulness of the DLV was demonstrated as well as the care that must be exercised in interpreting lidar data taken in a stable boundary layer in the vicinity of subtle terrain features.

Development of flood probability charts for urban drainage network in coastal areas through a simplified joint assessment approach

NASA Astrophysics Data System (ADS)

Archetti, R.; Bolognesi, A.; Casadio, A.; Maglionico, M.

2011-04-01

The operating conditions of urban drainage networks during storm events certainly depend on the hydraulic conveying capacity of conduits but also on downstream boundary conditions. This is particularly true in costal areas where the level of the receiving water body is directly or indirectly affected by tidal or wave effects. In such cases, not just different rainfall conditions (varying intensity and duration), but also different sea-levels and their effects on the network operation should be considered. This paper aims to study the behaviour of a seaside town storm sewer network, estimating the threshold condition for flooding and proposing a simplified method to assess the urban flooding severity as a function of either climate variables. The case study is a portion of the drainage system of Rimini (Italy), implemented and numerically modelled by means of InfoWorks CS code. The hydraulic simulation of the sewerage system has therefore allowed to identify the percentage of nodes of the drainage system where flooding is expected to occur. Combining these percentages with both climate variables values has lead to the definition charts representing the combined degree of risk "sea-rainfall" for the drainage system under investigation. A final comparison between such charts and the results obtained from a one-year sea-rainfall time series has confirmed the reliability of the analysis.

Development of flood probability charts for urban drainage network in coastal areas through a simplified joint assessment approach

NASA Astrophysics Data System (ADS)

Archetti, R.; Bolognesi, A.; Casadio, A.; Maglionico, M.

2011-10-01

The operating conditions of urban drainage networks during storm events depend on the hydraulic conveying capacity of conduits and also on downstream boundary conditions. This is particularly true in coastal areas where the level of the receiving water body is directly or indirectly affected by tidal or wave effects. In such cases, not just different rainfall conditions (varying intensity and duration), but also different sea-levels and their effects on the network operation should be considered. This paper aims to study the behaviour of a seaside town storm sewer network, estimating the threshold condition for flooding and proposing a simplified method to assess the urban flooding severity as a function of climate variables. The case study is a portion of the drainage system of Rimini (Italy), implemented and numerically modelled by means of InfoWorks CS code. The hydraulic simulation of the sewerage system identified the percentage of nodes of the drainage system where flooding is expected to occur. Combining these percentages with both climate variables' values has lead to the definition of charts representing the combined degree of risk "rainfall-sea level" for the drainage system under investigation. A final comparison between such charts and the results obtained from a one-year rainfall-sea level time series has demonstrated the reliability of the analysis.

Effects of drainage-basin geomorphology on insectivorous bird abundance in temperate forests.

PubMed

Iwata, Tomoya; Urabe, Jotaro; Mitsuhashi, Hiromune

2010-10-01

Interfaces between terrestrial and stream ecosystems often enhance species diversity and population abundance of ecological communities beyond levels that would be expected separately from both the ecosystems. Nevertheless, no study has examined how stream configuration within a watershed influences the population of terrestrial predators at the drainage-basin scale. We examined the habitat and abundance relationships of forest insectivorous birds in eight drainage basins in a cool temperate forest of Japan during spring and summer. Each basin has different drainage-basin geomorphology, such as the density and frequency of stream channels. In spring, when terrestrial arthropod prey biomass is limited, insectivorous birds aggregated in habitats closer to streams, where emerging aquatic prey was abundant. Nevertheless, birds ceased to aggregate around streams in summer because terrestrial prey became plentiful. Watershed-scale analyses showed that drainage basins with longer stream channels per unit area sustained higher densities of insectivorous birds. Moreover, such effects of streams on birds continued from spring through summer, even though birds dispersed out of riparian areas in the summer. Although our data are from only a single year, our findings imply that physical modifications of stream channels may reduce populations of forest birds; thus, they emphasize the importance of landscape-based management approaches that consider both stream and forest ecosystems for watershed biodiversity conservation. © 2010 Society for Conservation Biology.

Management Practices Used in Agricultural Drainage Ditches to Reduce Gulf of Mexico Hypoxia.

PubMed

Faust, Derek R; Kröger, Robert; Moore, Matthew T; Rush, Scott A

2018-01-01

Agricultural non-point sources of nutrients and sediments have caused eutrophication and other water quality issues in aquatic and marine ecosystems, such as the annual occurrence of hypoxia in the Gulf of Mexico. Management practices have been implemented adjacent to and in agricultural drainage ditches to promote their wetland characteristics and functions, including reduction of nitrogen, phosphorus, and sediment losses downstream. This review: (1) summarized studies examining changes in nutrient and total suspended solid concentrations and loads associated with management practices in drainage ditches (i.e., riser and slotted pipes, two-stage ditches, vegetated ditches, low-grade weirs, and organic carbon amendments) with emphasis on the Lower Mississippi Alluvial Valley, (2) quantified management system effects on nutrient and total suspended solid concentrations and loads and, (3) identified information gaps regarding water quality associated with these management practices and research needs in this area. In general, management practices used in drainage ditches at times reduced losses of total suspended solids, N, and P. However, management practices were often ineffective during storm events that were uncommon and intense in duration and volume, although these types of events could increase in frequency and intensity with climate change. Studies on combined effects of management practices on drainage ditch water quality, along with research towards improved nutrient and sediment reduction efficiency during intense storm events are urgently needed.

Acid mine drainage and subsidence: effects of increased coal utilization.

PubMed Central

Hill, R D; Bates, E R

1979-01-01

The increases above 1975 levels for acid mine drainage and subsidence for the years 1985 and 2000 based on projections of current mining trends and the National Energy Plan are presented. No increases are projected for acid mine drainage from surface mines or waste since enforcement under present laws should control this problem. The increase in acid mine drainage from underground mines is projected to be 16 percent by 1985 and 10 percent by 2000. The smaller increase in 2000 over 1985 reflects the impact of the PL 95-87 abandoned mine program. Mine subsidence is projected to increase by 34 and 115 percent respectively for 1985 and 2000. This estimate assumes that subsidence will parallel the rate of underground coal production and that no new subsidence control measures are adopted to mitigate subsidence occurrence. PMID:540617

A safe and effective method for treatment of chronic subdural haematoma.

PubMed

Gurelik, Mustafa; Aslan, Adem; Gurelik, Bilge; Ozum, Unal; Karadag, Ozen; Kars, H Zafer

2007-02-01

Burr-hole irrigation and burr-hole drainage without irrigation are the most popular methods for treatment of chronic subdural haematoma. It is not well known if irrigation is necessary or which method has a higher recurrence rate. We compared the recurrence rates of those two methods. Forty-two patients were treated by burr-hole irrigation (irrigation group), whereas 38 patients were treated by burr-hole drainage (drainage group). Recurrence rate and its relation with sex, age, haematoma localization and aetiology were investigated in both groups. There was no significant difference between recurrence rates of the two groups. There was also no correlation between recurrence rate and age, sex, haematoma localization, or aetiology. There was no significant difference between recurrence rates of the two groups. Since the burr-hole drainage method is simpler to carry out, its use may be preferable.

Perforated Duodenal Ulcer in High Risk Patients: Is Percutaneous Drainage Justified?

PubMed Central

Saber, Aly; Gad, Mohammad A; Ellabban, Gouda M

2012-01-01

Background: Conservative treatment was recommended as the treatment of choice in perforated acute peptic ulcer. Here, we adjunct percutaneous peritoneal drainage with nonoperative conservative treatment in high risk elderly patients with perforated duodenal ulcer. Aim: The work was to study the efficacy of percutaneous peritoneal drainage under local anesthesia supported by conservative measures in high risk elderly patients, according to the American Society of Anesthesiologists grading, with perforated duodenal ulcer. Patients and Methods: Twenty four high risk patients with age >65 years having associated medical illness with evidence of perforated duodenal ulcer. Results: The overall morbidity and mortality were comparable with those treated by conservative measures alone. Conclusion: In high risk patients with perforated peptic ulcer and established peritonitis, percutaneous peritoneal drainage under local anesthesia seems to be effective with least operative trauma and mortality rate. PMID:22393546

Effects of storm-water runoff on local ground-water quality, Clarksville, Tennessee

USGS Publications Warehouse

Hoos, Anne B.

1990-01-01

Storm-related water-quality data were collected at a drainage-well site and at a spring site in Clarksville, Tennessee, to define the effects of storm-water runoff on the quality of ground water in the area. A dye-trace test verified the direct hydraulic connection between the drainage well and Mobley Spring. Samples of storm run off and spring flow were collected at these sites for nine storms during the period February to October 1988. Water samples were collected also from Mobley Spring and two other springs and two observation wells in the area during dry-weather conditions to assess the general quality of ground water in an urban karst terrain. Evaluation of the effect of storm-water runoff on the quality of local ground water is complicated by the presence of other sources of contaminants in the area Concentrations and load for most major constituents were much smaller in storm-water runoff at the drainage well than in the discharge of Mobley Spring, indicating that much of the chemical constituent load discharged from the spring comes from sources other than the drainage well. However, for some of the minor constituents associated with roadway runoff (arsenic, copper, lead, organic carbon, and oil and grease), the drainage well contributed relatively large amounts of these constituents to local ground water during storms. The close correlation between concentrations of total organic carbon and concentrations of most trace metals at the drainage-well and Mobley Spring sites indicates that these constituents are transported together. Many trace metals were flushed early during each runoff event. Mean storm loads for copper, lead, zinc, and four nutrient species (total nitrogen, ammonia nitrogen, total phosphorus, and orthophosphorus) in storm-water runoff at the drainage-well site were lower than mean storm load predicted from an existing regression model. The overprediction by the model may be a result of the small size of the drainage area relative to the range of drainage areas used in the development of the models, or to the below-normal amounts of rainfall during the period of sampling for this investigation. Loads& in storm-water runoff for 22 constituents were extrapolated from sampled storms to total loads for the period February to October 1988. Calculated loads for trace metals for the period ranged from 0.030pound.s for cadmium to 12pound.s for strontium. Loads of the primary nutrients ranged from 0.97pounds for nitrite as nitrogen to 34pounds of organic nitrogen. Storm-water quality at the drainage-well and Mobley Spring sites was compared to background water quality of the local aquifer; as characterized by dry-weather samples from three springs and two observation wells in the Clarksville area. Concentrations of total-recoverable cadmium, chromium, copper, lead, and nickel were higher in many stormwater samples from both the drainage-well and Mobley Spring sites than in samples from any other site. In addition, concentrations of total organic carbon, methylene blue active substances, and total-recoverable oil and grease were generally higher in storm-water samples from the drainage-well site than in any ground-water sample. Densities of fecal coliform and fecal streptococcus bacteria and concentrations of total recoverable iron, manganese, and methylene blue active substances in storm samples from the drainage-well site exceeded the maximum contaminant levels listed in Tennessee?s drinking-water standards (1988) by as much as 2,500 and 5,500 colonies per 100 milliliters, and 2.7, 0.29, and 0.05 milligrams per liter, respectively. Densities of fecal coliform and fecal streptococcus bacteria and concentrations of total-recoverable iron, manganese, and lead in storm samples from Mobley Spring exceeded the maximum contaminant levels by as much as 500 and 4,500 colonies per 100 milliliters, and 18.7,0.65, and 0.02 milligrams per liter, respectively. For iron, manganese, and bacteria, these undesirable

Autogenic drainage for airway clearance in cystic fibrosis.

PubMed

McCormack, Pamela; Burnham, Paul; Southern, Kevin W

2017-10-06

Autogenic drainage is an airway clearance technique that was developed by Jean Chevaillier in 1967. The technique is characterised by breathing control using expiratory airflow to mobilise secretions from smaller to larger airways. Secretions are cleared independently by adjusting the depth and speed of respiration in a sequence of controlled breathing techniques during exhalation. The technique requires training, concentration and effort from the individual. It is important to systematically review the evidence demonstrating that autogenic drainage is an effective intervention for people with cystic fibrosis. To compare the clinical effectiveness of autogenic drainage in people with cystic fibrosis with other physiotherapy airway clearance techniques. We searched the Cochrane Cystic Fibrosis Trials Register, compiled from electronic database searches and handsearching of journals and conference abstract books. We also searched the reference lists of relevant articles and reviews, as well as two trials registers (31 August 2017).Dtae of most recent search of the Cochrane Cystic Fibrosis Trials Register: 25 September 2017. We identified randomised and quasi-randomised controlled studies comparing autogenic drainage to another airway clearance technique or no therapy in people with cystic fibrosis for at least two treatment sessions. Data extraction and assessments of risk of bias were independently performed by two authors. The authors assessed the quality of the evidence using the GRADE system. The authors contacted two investigators for further information pertinent to their published studies. Searches retrieved 35 references to 21 individual studies, of which seven (n = 208) were eligible for inclusion. One study was of parallel design with the remaining six being cross-over in design; participant numbers ranged from 17 to 75. The total study duration varied between four days and two years. The age of participants ranged between seven and 63 years with a wide range of disease severity reported. Six studies enrolled participants who were clinically stable, whilst participants in one study had been hospitalised with an infective exacerbation. All studies compared autogenic drainage to one (or more) other recognised airway clearance technique. Exercise is commonly used as an alternative therapy by people with cystic fibrosis; however, there were no studies identified comparing exercise with autogenic drainage.The quality of the evidence was generally low or very low. The main reasons for downgrading the level of evidence were the frequent use of a cross-over design, outcome reporting bias and the inability to blind participants.The review's primary outcome, forced expiratory volume in one second, was the most common outcome measured and was reported by all seven studies; only three studies reported on quality of life (also a primary outcome of the review). One study reported on adverse events and described a decrease in oxygen saturation levels whilst performing active cycle of breathing techniques, but not with autogenic drainage. Six of the seven included studies measured forced vital capacity and three of the studies used mid peak expiratory flow (per cent predicted) as an outcome. Six studies reported sputum weight. Less commonly used outcomes included oxygen saturation levels, personal preference, hospital admissions or intravenous antibiotics. There were no statistically significant differences found between any of the techniques used with respect to the outcomes measured except when autogenic drainage was described as being the preferred technique of the participants in one study over postural drainage and percussion. Autogenic drainage is a challenging technique that requires commitment from the individual. As such, this intervention merits systematic review to ensure its effectiveness for people with cystic fibrosis. From the studies assessed, autogenic drainage was not found to be superior to any other form of airway clearance technique. Larger studies are required to better evaluate autogenic drainage in comparison to other airway clearance techniques in view of the relatively small number of participants in this review and the complex study designs. The studies recruited a range of participants and were not powered to assess non-inferiority. The varied length and design of the studies made the analysis of pooled data challenging.

Changes in the Bacterial Community of Soil from a Neutral Mine Drainage Channel

PubMed Central

Pereira, Letícia Bianca; Vicentini, Renato; Ottoboni, Laura M. M.

2014-01-01

Mine drainage is an important environmental disturbance that affects the chemical and biological components in natural resources. However, little is known about the effects of neutral mine drainage on the soil bacteria community. Here, a high-throughput 16S rDNA pyrosequencing approach was used to evaluate differences in composition, structure, and diversity of bacteria communities in samples from a neutral drainage channel, and soil next to the channel, at the Sossego copper mine in Brazil. Advanced statistical analyses were used to explore the relationships between the biological and chemical data. The results showed that the neutral mine drainage caused changes in the composition and structure of the microbial community, but not in its diversity. The Deinococcus/Thermus phylum, especially the Meiothermus genus, was in large part responsible for the differences between the communities, and was positively associated with the presence of copper and other heavy metals in the environmental samples. Other important parameters that influenced the bacterial diversity and composition were the elements potassium, sodium, nickel, and zinc, as well as pH. The findings contribute to the understanding of bacterial diversity in soils impacted by neutral mine drainage, and demonstrate that heavy metals play an important role in shaping the microbial population in mine environments. PMID:24796430

Geochemistry of dissolved trace elements and heavy metals in the Dan River Drainage (China): distribution, sources, and water quality assessment.

PubMed

Meng, Qingpeng; Zhang, Jing; Zhang, Zhaoyu; Wu, Tairan

2016-04-01

Dissolved trace elements and heavy metals in the Dan River drainage basin, which is the drinking water source area of South-to-North Water Transfer Project (China), affect large numbers of people and should therefore be carefully monitored. To investigate the distribution, sources, and quality of river water, this study integrating catchment geology and multivariate statistical techniques was carried out in the Dan River drainage from 99 river water samples collected in 2013. The distribution of trace metal concentrations in the Dan River drainage was similar to that in the Danjiangkou Reservoir, indicating that the reservoir was significantly affected by the Dan River drainage. Moreover, our results suggested that As, Sb, Cd, Mn, and Ni were the major pollutants. We revealed extremely high concentrations of As and Sb in the Laoguan River, Cd in the Qingyou River, Mn, Ni, and Cd in the Yinhua River, As and Sb in the Laojun River, and Sb in the Dan River. According to the water quality index, water in the Dan River drainage was suitable for drinking; however, an exposure risk assessment model suggests that As and Sb in the Laojun and Laoguan rivers could pose a high risk to humans in terms of adverse health and potential non-carcinogenic effects.

Acceleration of tendon-bone healing of anterior cruciate ligament graft using intermittent negative pressure in rabbits.

PubMed

Sun, Zhengming; Wang, Xiaoqing; Ling, Ming; Wang, Wei; Chang, Yanhai; Yang, Guang; Dong, Xianghui; Wu, Shixun; Wu, Xueyuan; Yang, Bo; Chen, Ming

2017-04-18

The purpose of this study was to test effects of negative pressure on tendon-bone healing after reconstruction of anterior cruciate ligament (ACL) in rabbits. Hind legs of 24 New Zealand White rabbits were randomly selected as negative pressure group and the contralateral hind legs as control. Reconstruction of the ACL was done. Joints of the negative pressure side were placed with drainage tubes connecting the micro-negative pressure aspirator. Control side was placed with ordinary drainage tubes. Drainage tubes on both sides were removed at the same time 5 days after operation. After 6 weeks, joint fluid was drawn to detect the expression levels of interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α); at the same time, femur-ligament-tibia complex was obtained to determine tendon graft tension and to observe the histomorphology, blood vessels of the tendon-bone interface, and expression of vascular endothelial growth factor (VEGF). The maximum load breakage of tendon graft was significantly greater in the negative pressure group than in the control group (P < 0.05). Histological studies of the tendon-bone interface found that there was more new bone formation containing chondroid cells and aligned connective tissue in the negative pressure group than in the control group. Expression of VEGF was higher in the negative pressure group than in the control group (P < 0.01). Content of IL-1β and TNF-α in synovial fluid is lower in the negative pressure group than in the control group (P < 0.01). Intermittent negative pressure plays an active role in tendon-bone healing and creeping substitution of ACL reconstruction in the rabbits.

Ecotoxicological risks of the abandoned F-Ba-Pb-Zn mining area of Osor (Spain).

PubMed

Bori, Jaume; Vallès, Bettina; Navarro, Andrés; Riva, Maria Carme

2017-06-01

Due to its potential toxic properties, metal mobilization is of major concern in areas surrounding Pb-Zn mines. In the present study, metal contents and toxicity of soils, aqueous extracts from soils and mine drainage waters from an abandoned F-Ba-Pb-Zn mining area in Osor (Girona, NE Spain) were evaluated through chemical extractions and ecotoxicity bioassays. Toxicity assessment in the terrestrial compartment included lethal and sublethal endpoints on earthworms Eisenia fetida, arthropods Folsomia candida and several plant species, whereas aquatic tests involved bacteria Vibrio fischeri, microalgae Raphidocelis subcapitata and crustaceans Daphnia magna. Total concentrations of Ba (250-5110 mg kg -1 ), Pb (940 to >5000 mg kg -1 ) and Zn (2370-11,300 mg kg -1 ) in soils exceeded intervention values to protect human health. Risks for the aquatic compartment were identified in the release of drainage waters and in the potential leaching and runoff of metals from contaminated soils, with Cd (1.98-9.15 µg L -1 ), Pb (2.11-326 µg L -1 ) and Zn (280-2900 µg L -1 ) concentrations in filtered water samples surpassing US EPA Water Quality Criteria (2016a, b). Terrestrial ecotoxicity tests were in accordance with metal quantifications and identified the most polluted soil as the most toxic. Avoidance and reproduction tests with earthworms showed the highest sensitivity to metal contamination. Aquatic bioassays performed in aqueous extracts from soils confirmed the results from terrestrial tests and also detected toxic effects caused by the mine drainage waters. Algal growth inhibition was the most sensitive aquatic endpoint. In view of the results, the application of a containment or remediative procedure in the area is encouraged.

Role of endoscopic biliary drainage in advanced hepatocellular carcinoma with jaundice

PubMed Central

Han, Sung Yong; Heo, Jeong; Kim, Dong Uk; Baek, Dong Hoon; Yoo, So Yong; Kim, Chang Won; Kim, Suk; Song, Geun Am; Cho, Mong; Kang, Dae Hwan

2017-01-01

Background Patients with advanced hepatocellular carcinoma (HCC) with jaundice have an extremely poor prognosis. Although biliary drainage can resolve obstructive jaundice, signs of obstruction may not be evident. This study evaluated the role of endoscopic biliary drainage in patients with advanced HCC and obstructive jaundice. Methods From 2010 to 2015, 74 patients underwent endoscopic biliary drainage for obstructive jaundice due to advanced HCC. Jaundice resolution was defined as complete response and total bilirubin concentration below 3 mg/dl. Results The technical success rate in the 74 patients was 92.1% (70/76). Of the 70 patients who underwent successful biliary drainage, 48 (68.6%) and 22 (31.4%) were Child-Pugh classes B and C, respectively, and 10 (14.3%) and 60 (85.7%) were BCLC stages B and C, respectively. Intrahepatic bile duct (IHD) dilatation was observed in 35 patients (50%). After drainage, the complete response rate was 35.7% (25/70). The mean time to resolution was 17.4 ±8.5 days. However, jaundice was re-aggravated in 74.3% (15/25) after a mean 103.5 ±96.4 days. Multivariate analysis showed that the absence of ascites, presence of IHD dilatation, normal range of prothrombin time, and lower MELD score were significantly associated with complete response. The overall survival rate was 15.7% (11/70) and the median survival time is 28 days (95% confidence interval 2.6–563 days). Complete response and HCC treatment after drainage were significantly associated with survival. Conclusion Effective endoscopic biliary drainage is an important palliative treatment in patients with advanced HCC and obstructive jaundice, especially those with IHD dilatation and preserved liver function, as determined by ascites, prothrombin time, and MELD score. PMID:29095941

Role of endoscopic biliary drainage in advanced hepatocellular carcinoma with jaundice.

PubMed

Woo, Hyun Young; Han, Sung Yong; Heo, Jeong; Kim, Dong Uk; Baek, Dong Hoon; Yoo, So Yong; Kim, Chang Won; Kim, Suk; Song, Geun Am; Cho, Mong; Kang, Dae Hwan

2017-01-01

Patients with advanced hepatocellular carcinoma (HCC) with jaundice have an extremely poor prognosis. Although biliary drainage can resolve obstructive jaundice, signs of obstruction may not be evident. This study evaluated the role of endoscopic biliary drainage in patients with advanced HCC and obstructive jaundice. From 2010 to 2015, 74 patients underwent endoscopic biliary drainage for obstructive jaundice due to advanced HCC. Jaundice resolution was defined as complete response and total bilirubin concentration below 3 mg/dl. The technical success rate in the 74 patients was 92.1% (70/76). Of the 70 patients who underwent successful biliary drainage, 48 (68.6%) and 22 (31.4%) were Child-Pugh classes B and C, respectively, and 10 (14.3%) and 60 (85.7%) were BCLC stages B and C, respectively. Intrahepatic bile duct (IHD) dilatation was observed in 35 patients (50%). After drainage, the complete response rate was 35.7% (25/70). The mean time to resolution was 17.4 ±8.5 days. However, jaundice was re-aggravated in 74.3% (15/25) after a mean 103.5 ±96.4 days. Multivariate analysis showed that the absence of ascites, presence of IHD dilatation, normal range of prothrombin time, and lower MELD score were significantly associated with complete response. The overall survival rate was 15.7% (11/70) and the median survival time is 28 days (95% confidence interval 2.6-563 days). Complete response and HCC treatment after drainage were significantly associated with survival. Effective endoscopic biliary drainage is an important palliative treatment in patients with advanced HCC and obstructive jaundice, especially those with IHD dilatation and preserved liver function, as determined by ascites, prothrombin time, and MELD score.

Estimating drain flow from measured water table depth in layered soils under free and controlled drainage

NASA Astrophysics Data System (ADS)

Saadat, Samaneh; Bowling, Laura; Frankenberger, Jane; Kladivko, Eileen

2018-01-01

Long records of continuous drain flow are important for quantifying annual and seasonal changes in the subsurface drainage flow from drained agricultural land. Missing data due to equipment malfunction and other challenges have limited conclusions that can be made about annual flow and thus nutrient loads from field studies, including assessments of the effect of controlled drainage. Water table depth data may be available during gaps in flow data, providing a basis for filling missing drain flow data; therefore, the overall goal of this study was to examine the potential to estimate drain flow using water table observations. The objectives were to evaluate how the shape of the relationship between drain flow and water table height above drain varies depending on the soil hydraulic conductivity profile, to quantify how well the Hooghoudt equation represented the water table-drain flow relationship in five years of measured data at the Davis Purdue Agricultural Center (DPAC), and to determine the impact of controlled drainage on drain flow using the filled dataset. The shape of the drain flow-water table height relationship was found to depend on the selected hydraulic conductivity profile. Estimated drain flow using the Hooghoudt equation with measured water table height for both free draining and controlled periods compared well to observed flow with Nash-Sutcliffe Efficiency values above 0.7 and 0.8 for calibration and validation periods, respectively. Using this method, together with linear regression for the remaining gaps, a long-term drain flow record for a controlled drainage experiment at the DPAC was used to evaluate the impacts of controlled drainage on drain flow. In the controlled drainage sites, annual flow was 14-49% lower than free drainage.

Contrasting vulnerability of drained tropical and high-latitude peatlands to fluvial loss of stored carbon

NASA Astrophysics Data System (ADS)

Evans, Chris D.; Page, Susan E.; Jones, Tim; Moore, Sam; Gauci, Vincent; Laiho, Raija; Hruška, Jakub; Allott, Tim E. H.; Billett, Michael F.; Tipping, Ed; Freeman, Chris; Garnett, Mark H.

2014-11-01

Carbon sequestration and storage in peatlands rely on consistently high water tables. Anthropogenic pressures including drainage, burning, land conversion for agriculture, timber, and biofuel production, cause loss of pressures including drainage, burning, land conversion for agriculture, timber, and biofuel production, cause loss of peat-forming vegetation and exposure of previously anaerobic peat to aerobic decomposition. This can shift peatlands from net CO2 sinks to large CO2 sources, releasing carbon held for millennia. Peatlands also export significant quantities of carbon via fluvial pathways, mainly as dissolved organic carbon (DOC). We analyzed radiocarbon (14C) levels of DOC in drainage water from multiple peatlands in Europe and Southeast Asia, to infer differences in the age of carbon lost from intact and drained systems. In most cases, drainage led to increased release of older carbon from the peat profile but with marked differences related to peat type. Very low DOC-14C levels in runoff from drained tropical peatlands indicate loss of very old (centuries to millennia) stored peat carbon. High-latitude peatlands appear more resilient to drainage; 14C measurements from UK blanket bogs suggest that exported DOC remains young (<50 years) despite drainage. Boreal and temperate fens and raised bogs in Finland and the Czech Republic showed intermediate sensitivity. We attribute observed differences to physical and climatic differences between peatlands, in particular, hydraulic conductivity and temperature, as well as the extent of disturbance associated with drainage, notably land use changes in the tropics. Data from the UK Peak District, an area where air pollution and intensive land management have triggered Sphagnum loss and peat erosion, suggest that additional anthropogenic pressures may trigger fluvial loss of much older (>500 year) carbon in high-latitude systems. Rewetting at least partially offsets drainage effects on DOC age.

Early removal of urethral catheter with suprapubic tube drainage versus urethral catheter drainage alone after robot-assisted laparoscopic radical prostatectomy.

PubMed

Prasad, Sandip M; Large, Michael C; Patel, Amit R; Famakinwa, Olufenwa; Galocy, R Matthew; Karrison, Theodore; Shalhav, Arieh L; Zagaja, Gregory P

2014-07-01

Retrospective single institution data suggest that postoperative pain after robot-assisted laparoscopic radical prostatectomy is decreased by early removal of the urethral catheter with suprapubic tube drainage. In a randomized patient population we determined whether suprapubic tube drainage with early urethral catheter removal would improve postoperative pain compared with urethral catheter drainage alone. Men with a body mass index of less than 40 kg/m(2) who had newly diagnosed prostate cancer and elected robot-assisted laparoscopic radical prostatectomy were included in analysis. Block randomization by surgeon was used and randomization assignment was done after completing the urethrovesical anastomosis. In patients assigned to suprapubic tube drainage the urethral catheter was removed on postoperative day 1 and all catheters were removed on postoperative day 7. Visual analog pain scale and satisfaction questionnaires were administered on postoperative days 0, 1 and 7. A total of 29 patients were randomized to the urethral catheter vs 29 to the suprapubic tube plus early urethral catheter removal at the time of interim futility analysis. Mean visual analog pain scale scores did not differ between the groups at any time point and a similar percent of patients cited the catheter as the greatest bother with nonsignificant differences in treatment related satisfaction. Complications during postoperative week 1 did not vary between the groups. Based on interim results the trial was terminated due to lack of effect. Patients randomized to suprapubic tube vs urethral catheter drainage for the week after prostatectomy had similar pain, catheter related bother and treatment related satisfaction in the perioperative period. We no longer routinely offer suprapubic tube drainage with early urethral catheter removal at our institution. Copyright © 2014 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

Soil phosphorus loss in tile drainage water from long-term conventional- and non-tillage soils of Ontario with and without compost addition.

PubMed

Zhang, T Q; Tan, C S; Wang, Y T; Ma, B L; Welacky, T

2017-02-15

Recent ascertainment of tile drainage a predominant pathway of soil phosphorus (P) loss, along with the rise in concentration of soluble P in the Lake Erie, has led to a need to re-examine the impacts of agricultural practices. A three-year on-farm study was conducted to assess P loss in tile drainage water under long-term conventional- (CT) and non-tillage (NT) as influenced by yard waste leaf compost (LC) application in a Brookston clay loam soil. The effects of LC addition on soil P loss in tile drainage water varied depending on P forms and tillage systems. Under CT, dissolved reactive P (DRP) loss with LC addition over the study period was 765g P ha -1 , 2.9 times higher than CT without LC application, due to both a 50% increase in tile drainage flow volume and a 165% increase in DRP concentration. Under NT, DRP loss in tile drainage water with LC addition was 1447gPha -1 , 5.3 times greater than that for NT without LC application; this was solely caused by a 564% increase in DRP concentration. However, particulate P loads in tile drainage water with LC application remained unchanged, relative to non-LC application, regardless of tillage systems. Consequently, LC addition led to an increase in total P loads in tile drainage water by 57 and 69% under CT and NT, respectively. The results indicate that LC application may become an environmental concern due to increased DRP loss, particularly under NT. Crown Copyright © 2016. Published by Elsevier B.V. All rights reserved.

Shifted energy fluxes, increased Bowen ratios, and reduced thaw depths linked with drainage-induced changes in permafrost ecosystem structure

NASA Astrophysics Data System (ADS)

Göckede, Mathias; Kittler, Fanny; Kwon, Min Jung; Burjack, Ina; Heimann, Martin; Kolle, Olaf; Zimov, Nikita; Zimov, Sergey

2017-12-01

Hydrologic conditions are a key factor in Arctic ecosystems, with strong influences on ecosystem structure and related effects on biogeophysical and biogeochemical processes. With systematic changes in water availability expected for large parts of the northern high-latitude region in the coming centuries, knowledge on shifts in ecosystem functionality triggered by altered water levels is crucial for reducing uncertainties in climate change predictions. Here, we present findings from paired ecosystem observations in northeast Siberia comprising a drained and a control site. At the drainage site, the water table has been artificially lowered by up to 30 cm in summer for more than a decade. This sustained primary disturbance in hydrologic conditions has triggered a suite of secondary shifts in ecosystem properties, including vegetation community structure, snow cover dynamics, and radiation budget, all of which influence the net effects of drainage. Reduced thermal conductivity in dry organic soils was identified as the dominating drainage effect on energy budget and soil thermal regime. Through this effect, reduced heat transfer into deeper soil layers leads to shallower thaw depths, initially leading to a stabilization of organic permafrost soils, while the long-term effects on permafrost temperature trends still need to be assessed. At the same time, more energy is transferred back into the atmosphere as sensible heat in the drained area, which may trigger a warming of the lower atmospheric surface layer.

Water-quality assessment of the Albemarle-Pamlico drainage basin, North Carolina and Virginia; characterization of suspended sediment, nutrients, and pesticides

USGS Publications Warehouse

Harned, Douglas; McMahon, Gerard; Spruill, T.B.; Woodside, M.D.

1995-01-01

The 28,000-square-mile Albemarle-Pamlico drainage basin includes the Roanoke, Dan, Chowan Tar, and Neuse Rivers. The basin extends through four physiographic provinces in North Carolina and Virginia-Valley and Ridge, Blue Ridge, Piedmont and Coastal Plain. The spatial and temporal trends in ground-water and riverine water quality in the study area were characterized by using readily available data sources The primary data sources that were used included the U.S. Geological Survey's National Water Data Storage and Retrieval System (WATSTORE) database, the U.S. Environmental Protection Agency's Storage and Retrieval System (STORET) database, and results of a few investigations of pesticide occurrence. The principal water-quality constituents examined were suspended sediment, nutrients, and pesticides. The data examined generally spanned the period from 1950 to 1993. The only significant trends in suspended sediment were detected at three Chowan River tributary sites which showed long-term decreases. Suspended- and total-solids concentrations have decreased throughout the Albemarle-Pamlico drainage basin. The decreases are probably a result of (1) construction of new lakes and ponds in the basin, which trap solids, (2) improved agricultural soil management, and (3) improved wastewater treatment. Nutrient point sources are much less than nonpoint nutrient sources at the eight NASQAN basins examined for nutrient loads. The greatest nitrogen inputs are associated with crop fertilizer and biological nitrogen fixation by soybeans and peanuts, whereas atmospheric and animal-related nitrogen inputs are comparable in magnitude. The largest phosphorus inputs are associated with animal wastes. The most commonly detected pesticides in surface water in the STORET database were atrazine and aldrin.Intensive organonitrogen herbicide sampling of Chicod Creek in 1992 showed seasonal variations in pesticide concentration. The most commonly detected herbicides were atrazine, alachlor, metolachlor, prometon, and metribuzin. No relation between streamflow and pesticide concentration was evident.

Environmental heterogeneity, dispersal mode, and co-occurrence in stream macroinvertebrates

PubMed Central

Heino, Jani

2013-01-01

Both environmental heterogeneity and mode of dispersal may affect species co-occurrence in metacommunities. Aquatic invertebrates were sampled in 20–30 streams in each of three drainage basins, differing considerably in environmental heterogeneity. Each drainage basin was further divided into two equally sized sets of sites, again differing profoundly in environmental heterogeneity. Benthic invertebrate data were divided into three groups of taxa based on overland dispersal modes: passive dispersers with aquatic adults, passive dispersers with terrestrial winged adults, and active dispersers with terrestrial winged adults. The co-occurrence of taxa in each dispersal mode group, drainage basin, and heterogeneity site subset was measured using the C-score and its standardized effect size. The probability of finding high levels of species segregation tended to increase with environmental heterogeneity across the drainage basins. These patterns were, however, contingent on both dispersal mode and drainage basin. It thus appears that environmental heterogeneity and dispersal mode interact in affecting co-occurrence in metacommunities, with passive dispersers with aquatic adults showing random patterns irrespective of environmental heterogeneity, and active dispersers with terrestrial winged adults showing increasing segregation with increasing environmental heterogeneity. PMID:23467653

Investigations of lymphatic drainage from the interstitial space

NASA Astrophysics Data System (ADS)

Jayathungage Don, Tharanga; Richard Clarke Collaboration; John Cater Collaboration; Vinod Suresh Collaboration

2017-11-01

The lymphatic system is a highly complex biological system that facilitates the drainage of excess fluid in body tissues. In addition, it is an integral part of the immunological control system. Understanding the mechanisms of fluid absorption from the interstitial space and flow through the initial lymphatics is important to treat several pathological conditions. The main focus of this study is to computationally model the lymphatic drainage from the interstitial space. The model has been developed to consider a 3D lymphatic network and uses biological data to inform the creation of realistic geometries for the lymphatic capillary networks. We approximate the interstitial space as a porous region and the lymphatic vessel walls as permeable surfaces. The dynamics of the flow is approximated by Darcy's law in the interstitium and the Navier-Stokes equations in the lymphatic capillary lumen. The proposed model examines lymph drainage as a function of pressure gradient. In addition, we have examined the effects of interstitial and lymphatic wall permeabilities on the lymph drainage and the solute transportation in the model. The computational results are in accordance with the available experimental measurements.

Removal of selenium from contaminated agricultural drainage water by nanofiltration membranes

USGS Publications Warehouse

Kharaka, Y.K.; Ambats, G.; Presser, T.S.; Davis, R.A.

1996-01-01

Seleniferous agricultural drainage wastewater has become a new major source of pollution in the world. In the USA, large areas of farmland in 17 western states, generate contaminated salinized drainage with Se concentrations much higher than 5 ??g/l, the US Environmental Protection Agency water-quality criterion for the protection of aquatic life; Se values locally reach 4200 ??g/l in western San Joaquin Valley, California. Wetland habitats receiving this drainage have generally shown Se toxicosis in aquatic birds causing high rates of embryonic deformity and mortality, or have indicated potential ecological damage. Results of our laboratory flow experiments indicate that nanofiltration, the latest membrane separation technology, can selectively remove > 95% of Se and other multivalent anions from > 90% of highly contaminated water from the San Joaquin Valley, California. Such membranes yield greater water output and require lower pressures and less pretreatment, and therefore, are more cost effective than traditional reverse osmosis membranes. Nanofiltration membranes offer a potential breakthrough for the management of Se contaminated wastes not only from agricultural drainage, but from other sources also.

Evaluating Inundation in Urban Drainage Systems in Tamalanrea District Makassar Based Ecodrainase

NASA Astrophysics Data System (ADS)

Alfidhdha, Rizky; Karnaningroem, Nieke

2018-03-01

Makassar City is one of the major cities in Indonesia with a population of approximately 1.7 million inhabitants, which continues to grow and followed the development of urban infrastructure facilities. The development also resulted in adverse effects on the environment, especially for water catchment area turns into a watertight region resulting changes in surface runoff were greater, especially in the rainy season because the drainage coefficient values are increasing as well. The purpose of this study was to analyze the capacity of the capacity of drainage channels in terms of technical aspects, analyze and formulate efforts to address flooding in a drainage channel system environmentally friendly in terms of environmental aspects, and Calculating the cost and benefit the development of the handling of flooding with a drainage channel system environmentally friendly in terms of financial aspects. The results obtained from the analysis of the technical aspects there are 14 of 41 channel capacity is insufficient accommodation capacity, resulting in the analysis of environmental aspects require 867 infiltration wells, and 3.19 rate of Benefit Cost Ratio (BCR).

Pesticides in the surface waters of Lake Vistonis Basin, Greece: Occurrence and environmental risk assessment.

PubMed

Papadakis, Emmanouil-Nikolaos; Tsaboula, Aggeliki; Kotopoulou, Athina; Kintzikoglou, Katerina; Vryzas, Zisis; Papadopoulou-Mourkidou, Euphemia

2015-12-01

A study was undertaken for the evaluation of the pesticide pollution caused by the agricultural activities in the basin of Lake Vistonis, Greece during the years 2010-2012. Water samples were collected from Lake Vistonis, four major rivers and various small streams and agriculture drainage canals. The concentration of 302 compounds was determined after solid-phase extraction of the water samples and subsequent LC-MS/MS and GC-MS/MS analysis of the extracts. Overall, herbicides were the most frequently detected pesticides (57%), followed by insecticides (28%) and fungicides (14%). In Lake Vistonis 11 pesticides were detected. Specifically, fluometuron was detected in the 75% of the samples (maximum concentration 0.088 μg/L) whereas lambda-cyhalothrin was detected in all the samples of spring 2011 and alphamethrin in all the samples of spring 2012 (maximum concentration 0.041 and 0.168 μg/L, respectively). In the rivers and drainage canals 68 pesticides were detected. Specifically, fluometuron was detected in the 53% of the samples (maximum concentration 317.6 μg/L) followed by chlorpyrifos and prometryn (16 and 13% of the samples respectively). An environmental risk assessment was performed by employing the Risk Quotient (RQ) method. The risk assessment revealed that at least one pesticide concentration led to a RQ>1 in 20% of the samples. In Lake Vistonis, alphamethrin and lambda-cyhalothrin concentrations resulted in RQ>1, whereas in the other water bodies this was mainly the result of chlorpyrifos-methyl and alphamethrin exposure. In contrast, herbicide and fungicide concentrations contributed substantially less to environmental risks. Copyright © 2015 Elsevier B.V. All rights reserved.

Influence of previous breast surgery in sentinel lymph node biopsy in patients with breast cancer.

PubMed

López-Prior, V; Díaz-Expósito, R; Casáns Tormo, I

The aim of this study was to review the feasibility of selective sentinel lymph node biopsy in patients with previous surgery for breast cancer, as well as to examine the factors that may interfere with sentinel node detection. A retrospective review was performed on 91 patients with breast cancer and previous breast surgery, and who underwent sentinel lymph node biopsy. Patients were divided into two groups according to their previous treatment: aesthetic breast surgery in 30 patients (group I) and breast-conserving surgery in 61 (group II). Lymphoscintigraphy was performed after an intra-tumour injection in 21 cases and a peri-areolar injection in 70 cases. An analysis was made of lymphatic drainage patterns and overall sentinel node detection according to clinical, pathological and surgical variables. The overall detection of the sentinel lymph node in the lymphoscintigraphy was 92.3%, with 7.7% of extra-axillary drainages. The identification rate was similar after aesthetic breast surgery (93.3%) and breast-conserving surgery (91.8%). Sentinel lymph nodes were found in the contralateral axilla in two patients (2.2%), and they were included in the histopathology study. The non-identification rate in the lymphoscintigraphy was 7.7%. There was a significantly higher non-detection rate in the highest histological grade tumours (28.6% grade III, 4.5% grade I and 3.6% grade II). Sentinel lymph node biopsy in patients with previous breast surgery is feasible and deserves further studies to assess the influence of different aspects in sentinel node detection in this clinical scenario. A high histological grade was significantly associated with a lower detection. Copyright © 2017 Elsevier España, S.L.U. y SEMNIM. All rights reserved.

Stream channel responses to streamflow diversion on small streams of the Snake River drainage, Idaho

Treesearch

Carolyn C. Bohn; John G. King

2000-01-01

The effects on channels of small, low-head seasonal water diversions in the Snake River drainage were investigated. Channels below small diversions were compared to the channels immediately above the same diversions to determine if differences in flow conveyance, substrate sediment size distribution, or streamside vegetation density were present. Estimates of flow...

Design of an Orifice and Weir Outlet for Poorly Drained Forested Watersheds

Treesearch

D.M. Amatya; R.W. Skaggs; J.H. Hughes

1999-01-01

Orifice-weir structures at ditch outlets are being used to reduce peak drainage rates and to store water during the growing season in poorly drained managed pine plantations. Earlier studies have shown their effectiveness on reducing drainage outflows while conserving water during the growing season. This study reports on criteria and preliminary guidelines for...

Nutrient and sediment transport from a new vineyard within oak woodland

Treesearch

Royce Larsen; LynneDee Althouse; Daniel Meade; Mark Battany

2008-01-01

Water quality was investigated in the vicinity of Cuesta Ridge Vineyard, San Luis Obispo County, where drainages carry water from chaparral, oak woodland, and a new vineyard. Three drainages were instrumented with gauges above and below the vineyard for stage height and turbidity to assess the effectiveness of water quality protection measures at the Cuesta Ridge...

Projected climate change effects on subsurface drainage and the performance of controlled drainage in the Western Lake Erie Basin

USDA-ARS?s Scientific Manuscript database

The US Midwest is expected to experience higher intensity rainfall events along with an increased chance of drought during the mid- and late-21st century under climate change. Development of strategies to mitigate the impact of these projected changes on agricultural production may be critical for e...

Weather, landscape, and management effects on nitrate and soluble phosphorus concentrations in subsurface drainage discharge in the western Lake Erie basin

USDA-ARS?s Scientific Manuscript database

Subsurface drainage, while an important and necessary agricultural production practice in the Midwest, contributes nitrate (NO3) and soluble phosphorus (P) to surface waters. Eutrophication (i.e., excessive enrichment of waters by NO3 and soluble P) supports harmful algal blooms (HABs) in receiving ...

Effect of replacing surface inlets with blind or gravel inlets on sediment and phosphorus subsurface drainage losses

USDA-ARS?s Scientific Manuscript database

Open surface inlets that connect to subsurface tile drainage systems provide a direct pathway for sediment, nutrients, and agrochemicals to surface waters. This study was conducted to determine whether modifying open inlets by burying them in gravel capped with 30 cm of sandy clay loam soil or in ve...

Testing of DRAINMOD for Forested Watersheds with Non-Pattern Drainage

Treesearch

Devendra M. Amatya; Ge Sun; R. Wayne Skaggs; Carl C. Trettin

2003-01-01

Models like DRAINMOD and its forestry version, DRAINLOB, have been specifically developed as a field scale model for evaluating hydrologic effects of crops (trees), soil, and water management practices for lands with pattern drainage (i.e. with parallel ditches) on relatively flat, high water table soils. These models conduct a water balance between the ditches to...

Winter Cover Crop Effects on Nitrate Leaching in Subsurface Drainage as Simulated by RZWQM-DSSAT

NASA Astrophysics Data System (ADS)

Malone, R. W.; Chu, X.; Ma, L.; Li, L.; Kaspar, T.; Jaynes, D.; Saseendran, S. A.; Thorp, K.; Yu, Q.

2007-12-01

Planting winter cover crops such as winter rye (Secale cereale L.) after corn and soybean harvest is one of the more promising practices to reduce nitrate loss to streams from tile drainage systems without negatively affecting production. Because availability of replicated tile-drained field data is limited and because use of cover crops to reduce nitrate loss has only been tested over a few years with limited environmental and management conditions, estimating the impacts of cover crops under the range of expected conditions is difficult. If properly tested against observed data, models can objectively estimate the relative effects of different weather conditions and agronomic practices (e.g., various N fertilizer application rates in conjunction with winter cover crops). In this study, an optimized winter wheat cover crop growth component was integrated into the calibrated RZWQM-DSSAT hybrid model and then we compare the observed and simulated effects of a winter cover crop on nitrate leaching losses in subsurface drainage water for a corn-soybean rotation with N fertilizer application rates over 225 kg N ha-1 in corn years. Annual observed and simulated flow-weighted average nitrate concentration (FWANC) in drainage from 2002 to 2005 for the cover crop treatments (CC) were 8.7 and 9.3 mg L-1 compared to 21.3 and 18.2 mg L-1 for no cover crop (CON). The resulting observed and simulated FWANC reductions due to CC were 59% and 49%. Simulations with the optimized model at various N fertilizer rates resulted in average annual drainage N loss differences between CC and CON to increase exponentially from 12 to 34 kg N ha-1 for rates of 11 to 261 kg N ha-1. The results suggest that RZWQM-DSSAT is a promising tool to estimate the relative effects of a winter crop under different conditions on nitrate loss in tile drains and that a winter cover crop can effectively reduce nitrate losses over a range of N fertilizer levels.

Implications of deep drainage through saline clay for groundwater recharge and sustainable cropping in a semi-arid catchment, Australia

NASA Astrophysics Data System (ADS)

Timms, W. A.; Young, R. R.; Huth, N.

2011-11-01

The magnitude and timing of deep drainage and salt leaching through clay soils is a critical issue for dryland agriculture in semi-arid regions (<500 mm yr-1 rainfall), such as parts of Australia's Murray-Darling Basin (MDB). In this unique study, hydrogeological measurements and estimations of the historic water balance of crops grown on overlying Grey Vertosols were combined to estimate the contribution of deep drainage below crop roots to recharge and salinization of shallow groundwater. Soil sampling at two sites on the alluvial flood plain of the Lower Namoi catchment revealed significant peaks in chloride concentrations at 0.8-1.2 m depth under perennial vegetation and at 2.0-2.5 m depth under continuous cropping indicating deep drainage and salt leaching since conversion to cropping. Total salt loads of 91-229 t ha-1 NaCl equivalent were measured for perennial vegetation and cropping, with salinity to ≥10 m depth that is not detected by shallow soil surveys. Groundwater salinity varied spatially from 910 to 2430 mS m-1 at 21 to 37 m depth (N = 5), whereas deeper groundwater was less saline (290 mS m-1) with use restricted to livestock and rural domestic supplies in this area. The Agricultural Production Systems Simulator (APSIM) software package predicted deep drainage of 3.3-9.5 mm yr-1 (0.7-2.1% rainfall) based on site records of grain yields, rainfall, salt leaching and soil properties. Predicted deep drainage was highly episodic, dependent on rainfall and antecedent, and over a 39 yr period was restricted mainly to the record wet winter of 1998. During the study period, groundwater levels were unresponsive to major rainfall events (70 and 190 mm total), and most piezometers at about 18 m depth remained dry. In this area, at this time, recharge negligible due to low rainfall and large potential evapotranspiration, transient hydrological conditionsafter changes in land use and a thick clay dominated vadose zone. This is in contrast to regional groundwater modelling that assumes annual recharge of 0.5% of rainfall. Importantly, it was found that leaching from episodic deep drainage could not cause discharge of saline groundwater in the area, since the water table was several meters below the incised river bed.

Yeast and bacterial diversity along a transect in an acidic, As-Fe rich environment revealed by cultural approaches.

PubMed

Delavat, François; Lett, Marie-Claire; Lièvremont, Didier

2013-10-01

Acid mine drainages (AMDs) are often thought to harbour low biodiversity, yet little is known about the diversity distribution along the drainages. Using culture-dependent approaches, the microbial diversity from the Carnoulès AMD sediment was investigated for the first time along a transect showing progressive environmental stringency decrease. In total, 20 bacterial genera were detected, highlighting a higher bacterial diversity than previously thought. Moreover, this approach led to the discovery of 16 yeast species, demonstrating for the first time the presence of this important phylogenetic group in this AMD. All in all, the location of the microbes along the transect helps to better understand their distribution in a pollution gradient. Copyright © 2013 Elsevier B.V. All rights reserved.

A model to measure lymphatic drainage from the eye.

PubMed

Kim, Minhui; Johnston, Miles G; Gupta, Neeru; Moore, Sara; Yücel, Yeni H

2011-11-01

Intraocular pressure (IOP) is the most important risk factor for glaucoma development and progression. Most anti-glaucoma treatments aim to lower IOP by enhancing aqueous humor drainage from the eye. Aqueous humor drainage occurs via well-characterized trabecular meshwork (TM) and uveoscleral (UVS) pathways, and recently described ciliary body lymphatics. The relative contribution of the lymphatic pathway to aqueous drainage is not known. We developed a sheep model to quantitatively assess lymphatic drainage along with TM and UVS outflows. This study describes that model and presents our initial findings. Following intracameral injection of (125)I-bovine serum albumin (BSA), lymph was continuously collected via cannulated cervical lymphatic vessels and the thoracic lymphatic duct over either a 3-h or 5-h time period. In the same animals, blood samples were collected from the right jugular vein every 15 min. Lymphatic and TM drainage were quantitatively assessed by measuring (125)I-BSA in lymph and plasma, respectively. Radioactive tracer levels were also measured in UVS and "other" ocular tissue, as well as periocular tissue harvested 3 and 5 h post-injection. Tracer recovered from UVS tissue was used to estimate UVS drainage. The amount of (125)I-BSA recovered from different fluid and tissue compartments was expressed as a percentage of total recovered tracer. Three hours after tracer injection, percentage of tracer recovered in lymph and plasma was 1.64% ± 0.89% and 68.86% ± 9.27%, respectively (n = 8). The percentage of tracer in UVS, other ocular and periocular tissues was 19.87% ± 5.59%, 4.30% ± 3.31% and 5.32% ± 2.46%, respectively. At 5 h (n = 2), lymphatic drainage was increased (6.40% and 4.96% vs. 1.64%). On the other hand, the percentage of tracer recovered from UVS and other ocular tissue had decreased, and the percentage from periocular tissue showed no change. Lymphatic drainage increased steadily over the 3 h post-injection period, while TM drainage increased rapidly - reaching a plateau at 30 min. This quantitative sheep model enables assessment of relative contributions of lymphatic drainage, TM and UVS outflows, and may help to better understand the effects of glaucoma agents on outflow pathways. Copyright © 2011 Elsevier Ltd. All rights reserved.

Water quality in irrigation and drainage networks of Thessaloniki plain in Greece related to land use, water management, and agroecosystem protection.

PubMed

Litskas, Vassilis D; Aschonitis, Vassilis G; Antonopoulos, Vassilis Z

2010-04-01

A representative agricultural area of 150 ha located in a protected ecosystem (Axios River Delta, Thermaikos Gulf-N. Aegean, Greece) was selected in order to investigate water quality parameters [pH, electrical conductivity (EC(w)), NO(3)-N, NH(4)-N, total phosphorus (TP)] in irrigation and drainage water. In the study area, the cultivated crops are mainly rice, maize, cotton, and fodder. Surface irrigation methods are applied using open channels network, and irrigation water is supplied by Axios River, which is facing pollution problems. The return flow from surface runoff and the surplus of irrigation water are collected to drainage network and disposed to Thermaikos Gulf. A 2-year study (2006-2007) was conducted in order to evaluate the effects of land use and irrigation water management on the drainage water quality. The average pH and NO(3)-N concentration was higher in the irrigation water (8.0 and 1.3 mg/L, respectively) than that in the drainage water (7.6 and 1.0 mg/L, respectively). The average EC(W), NH(4)-N, and TP concentration was higher in the drainage water (1,754 muS/cm, 90.3 microg/L, and 0.2 mg/L, respectively) than that in the irrigation water (477.1 muS/cm, 46.7 microg/L, and 0.1 mg/L, respectively). Average irrigation efficiency was estimated at 47% and 51% in 2006 and 2007 growing seasons (April-October), respectively. The loads of NO(3)-N in both seasons were higher in the irrigation water (35.1 kg/ha in 2006 and 24.9 kg/ha in 2007) than those in the drainage water (8.1 kg/ha in 2006 and 7.6 kg/ha in 2007). The load of TP was higher in the irrigation water in season 2006 (2.8 kg/ha) than that in the drainage water (1.1 kg/ha). Total phosphorus load in 2007 was equal in irrigation and drainage water (1.2 kg/ha). Wetland conditions, due to rice irrigation regime, drainage network characteristics, and the crop distribution in the study area, affect the drainage water ending in the protected ecosystem of Thermaikos Gulf.

Hydrography change detection: the usefulness of surface channels derived From LiDAR DEMs for updating mapped hydrography

USGS Publications Warehouse

Poppenga, Sandra K.; Gesch, Dean B.; Worstell, Bruce B.

2013-01-01

The 1:24,000-scale high-resolution National Hydrography Dataset (NHD) mapped hydrography flow lines require regular updating because land surface conditions that affect surface channel drainage change over time. Historically, NHD flow lines were created by digitizing surface water information from aerial photography and paper maps. Using these same methods to update nationwide NHD flow lines is costly and inefficient; furthermore, these methods result in hydrography that lacks the horizontal and vertical accuracy needed for fully integrated datasets useful for mapping and scientific investigations. Effective methods for improving mapped hydrography employ change detection analysis of surface channels derived from light detection and ranging (LiDAR) digital elevation models (DEMs) and NHD flow lines. In this article, we describe the usefulness of surface channels derived from LiDAR DEMs for hydrography change detection to derive spatially accurate and time-relevant mapped hydrography. The methods employ analyses of horizontal and vertical differences between LiDAR-derived surface channels and NHD flow lines to define candidate locations of hydrography change. These methods alleviate the need to analyze and update the nationwide NHD for time relevant hydrography, and provide an avenue for updating the dataset where change has occurred.

[Treatment of the first episode of spontaneous pneumothorax].

PubMed

Moubachir, H; Zaghba, N; Benjelloun, H; Bakhatar, A; Yassine, N

2016-11-01

The management of a first episode of spontaneous pneumothorax is controversial and the best technique to be used as an initial intervention, aspiration or intercostal drainage, is still debated. We present a retrospective case series during two and a half consecutive years describing the immediate management of spontaneous pneumothoraces, comparing aspiration versus thoracic drainage. One hundred and thirty-three clinical files from patients with spontaneous pneumothoraces were analyzed (17 primary and 116 secondary). The pneumothoraces were of varying size and different etiologies. Patients were initially treated with simple aspiration in 68 cases, with an immediate success rate of 37.5%, intercostal drainage in 49 cases, and by rest alone in 16 cases. In case of secondary pneumothorax, aspiration appeared to offer advantages as an initial strategy over intercostal drainage in terms of hospital stay (11 versus 22 days), and with significant effectiveness (37.5%). Copyright © 2016 SPLF. Published by Elsevier Masson SAS. All rights reserved.

Results of single burr hole drainage for acute subdural hematoma with non-reactive pupil.

PubMed

Yanagawa, Youichi; Sakamoto, Toshihisa

2012-01-01

To investigate the effects of emergency burr hole drainage for acute subdural hematoma (ASDH) with bilateral non-reactive pupils. A retrospective study was conducted by reviewing medical records from 1998 to 2007. Patients meeting the following criteria were included: 1) head injury with unconsciousness (Glasgow Coma Scale score 8); 2) bilateral non-reactive pupils on arrival; 3) ASDH with disappearance of basal cistern on computed tomography (CT); and 4) performance of emergency single burr hole drainage. Subjects were divided into survival and non-survival groups. Pupil size on the small side was significantly smaller in the survival group than in the non-survival group. All pupils on the small side in the survival group were 4 mm. Emergency burr hole drainage should still be considered in patients with ASDH showing bilateral non-reactive pupils and one pupil 4 mm.

Landform Formation Under Ice Sheets

NASA Astrophysics Data System (ADS)

Schoof, C. G.; Ng, F. S.; Hallet, B.

2004-12-01

We present a new mathematical model for the formation of subglacial landforms such as drumlins under a warm-based, soft-bedded ice sheet. At the heart of the model is a channelized drainage system in which smaller channels grow at the expense of larger ones, leading to the continuous creation and extinction of drainage paths, and to a spatially distributed imprint on the landscape. We demonstrate how interactions between such a drainage system, bed topography and ice flow can lead to the spontaneous formation of subglacial landforms, and discuss the effect of different sediment transport characteristics in the drainage system on the shape and migration of these landforms. This mathematical model is the first component of a study of landscape/ice-sheet self-organization, which is inspired and guided, in part, by new digital topographic data (LIDAR) that are revealing with unprecedented detail the striking grain of glacially scoured topography on length scales ranging from 0.5 to 20 km.

Endoscopic Stent Placement in the Palliation of Malignant Biliary Obstruction

PubMed Central

2011-01-01

Biliary drainage with biliary stent placement is the treatment of choice for palliation in patients with malignant biliary obstruction caused by unresectable neoplasms. In such patients, the endoscopic approach can be initially used with percutaneous radiological intervention. In patients with unresectable malignant distal bile duct obstructions, endoscopic biliary drainage with biliary stent placement has now become the main and least invasive palliative modality, which has been proven to be more effective in >80% of cases with lower morbidity than surgery, and perhaps may provide a survival benefit. In patients with unresectable malignant hilar obstruction, the endoscopic approach for biliary drainage with biliary stent placement has also been considered as the treatment of choice. There is still a lack of clear consensus on the use of covered versus uncovered metal stents in malignant distal bile duct obstructions and plastic versus metal stents and unilateral versus bilateral drainage in malignant hilar obstructions. PMID:22741117

Water quality issues associated with agricultural drainage in semiarid regions

NASA Astrophysics Data System (ADS)

Sylvester, Marc A.

High incidences of mortality, birth defects, and reproductive failure in waterfowl using Kesterson Reservoir in the San Joaquin Valley, Calif., have occurred because of the bioaccumulation of selenium from irrigation drainage. These circumstances have prompted concern about the quality of agriculture drainage and its potential effects on human health, fish and wildlife, and beneficial uses of water. The U.S. Geological Survey (USGS) and Lawrence Berkeley Laboratory, University of California (Berkeley, Calif.) organized a 1-day session at the 1986 AGU Fall Meeting in San Francisco, Calif., to provide an interdisciplinary forum for hydrologists, geochemists, and aquatic chemists to discuss the processes controlling the distribution, mobilization, transport, and fate of trace elements in source rocks, soils, water, and biota in semiarid regions in which irrigated agriculture occurs. The focus of t h e session was the presentation of research results on the source, distribution, movement, and fate of selenium in agricultural drainage.

Spatial and temporal patterns of pesticide concentrations in streamflow, drainage and runoff in a small Swedish agricultural catchment.

PubMed

Sandin, Maria; Piikki, Kristin; Jarvis, Nicholas; Larsbo, Mats; Bishop, Kevin; Kreuger, Jenny

2018-01-01

A better understanding of the dominant source areas and transport pathways of pesticide losses to surface water is needed for targeting mitigation efforts in a more cost-effective way. To this end, we monitored pesticides in surface water in an agricultural catchment typical of one of the main crop production regions in Sweden. Three small sub-catchments (88-242ha) were selected for water sampling based on a high-resolution digital soil map developed from proximal sensing methods and soil sampling; one sub-catchment had a high proportion of clay soils, another was dominated by coarse sandy soils while the third comprised a mix of soil types. Samples were collected from the stream, from field drains discharging into the stream and from within-field surface runoff during spring and early summer in three consecutive years. These samples were analyzed by LC-MS/MS for 99 compounds, including most of the polar and semi-polar pesticides frequently used in Swedish agriculture. Information on pesticide applications (products, doses and timing) was obtained from annual interviews with the farmers. There were clear and consistent differences in pesticide occurrence in the stream between the three sub-catchments, with both the numbers of detected compounds and concentrations being the largest in the area with a high proportion of clay soils and with very few detections in the sandy sub-catchment. Macropore flow to drains was most likely the dominant loss pathway in the studied area. Many of the compounds that were detected in drainage and stream water samples had not been applied for several years. This suggests that despite the predominant role of fast flow pathways in determining losses to the stream, long-term storage along the transport pathways also occurs, presumably in subsoil horizons where degradation is slow. Copyright © 2017 Elsevier B.V. All rights reserved.

Prognosis of flow conditions for de-centralized seepage of rainwater from roads

NASA Astrophysics Data System (ADS)

Meyer, Martin; Hasan, Issa; Sallwey, Jana; Graeber, Peter-Wolfgang

2013-04-01

Urbanization programs that include the construction of new settlements or roads lead to an increase in surface sealing. Conventional road drainage is being carried out by a rainwater sewage system coupled with collection and detention basins. This leads to local decreases in evaporation and groundwater recharge, disturbing the natural local water balance. The increased number of climate changed induced extreme precipitation events leads to a higher risk of road floodings as a result of a failure of these systems. Furthermore, the treatment of the discharge loaded with contaminants (such as heavy metals and MTBE) is resolved neither ecologically nor technologically. By using a natural, effective and sustainable evaporation and drainage strategy it is possible to reduce the probability of road floodings, to restore the natural local water balance and to establish ecologically and economically more beneficial rainwater drainage. By using PCSiWaPro®, a simulation tool for unsaturated soil zone processes developed at the Institute of Waste Management and the Technical University of Dresden, the effects of different atmospheric, hydrological and hydrogeological parameters and system conditions on the subsurface drainage flow conditions in the vicinity of a typical German highway road were studied. Special attention was given to the influence of extreme precipitation events on the drainage time at differently tilted parts of the surface, on surface drainages from lateral noise-protection barriers and on the probability of road surface underwashing. Differently constructed upper soil stratifications were tested for their ability to quickly drain water into the ground, which, besides the reduced risk of road flooding, also influence the duration time for the drainage water in each soil layer. Individual rainwater infiltration rates were applied for different regions of the model. The behaviours of three different types of soil (coarse sand, slightly silty sand and medium silty sand) were tested for their applicability as road base materials. The simulation results showed that for extreme precipitation events, the optimized decentralized road drainage system was able to discharge the accumulated rainwater. In future applications, the unsaturated flow model will be extended to a reactive transport model in order to develop strategies for optimal local drainage system design with special regard to natural purification features of different soil layer types. Additionally, PCSiWaPro® can be coupled to a groundwater model to simulate the influence of potential local groundwater contamination by road discharge on the whole underlying aquifer.

Protocol of a prospective cohort study of the effect of different methods of drainage of neuropathic bladder on occurrence of symptomatic urinary infection, and adverse events related to the urinary drainage system in spinal cord injury patients

PubMed Central

Vaidyanathan, Subramanian; Soni, Bhakul M; Gurpreet, Singh; Mansour, Paul; Hughes, Peter L; Oo, Tun; Sett, Pradipkumar; Parsons, Keith F; Davies, John C

2001-01-01

Background To present a protocol of a prospective, cohort study in which four groups of spinal cord injury (SCI) patients will participate. (Patients with indwelling urethral catheter; patients who perform intermittent catheterisation without wearing a penile sheath; patients who perform intermittent catheterisation and wear penile sheath as well; and patients with penile sheath drainage). Objectives (1) What is the incidence of symptomatic urinary infection in men with spinal cord injury who use different types of bladder drainage? (2) Which are predisposing factors for the occurrence of symptomatic urinary infection in men with spinal cord injury who practise different methods of bladder drainage? (3) What is the incidence of catheter and urinary drainage system-related adverse events in the four groups of SCI patients? Patients The criteria for inclusion are as follow: (1) Male patients with neuropathic bladder due to spinal cord injury, who are registered with the Regional Spinal Injuries Centre, Southport, England. (2) Age: 18 years or above. (3) Patients who are willing to give informed consent for participation in the study. (4) Patients willing to be contacted every two weeks by a staff of the spinal unit for 36 months. (5) Patients who are willing to maintain an accurate record of adverse events related to urinary catheter and urinary drainage system and predisposing factors for the occurrence of symptomatic urinary infection. (6) Patients, who are stabilised in a particular method of bladder drainage, and therefore, unlikely to make a permanent change in the method of bladder drainage (e.g. from penile sheath drainage to the use of long-term indwelling catheter) during a foreseeable future. Methods The participants will be observed for a period of 36 months. A staff of the spinal injuries unit will contact the participants by telephone every two weeks on a mutually agreed day and time. The information obtained during this standardised telephonic interview conducted once in two weeks will be entered in a database. When a participant develops symptom(s) suggestive of urinary infection, he will undergo urine and blood tests, and imaging studies of the urinary tract. Conclusion This study will provide information regarding the occurrence of symptomatic urinary infection, predisposing factors for development of urinary infection, and adverse events related to urinary catheter and urinary drainage system in SCI patients using different methods of bladder drainage. PMID:11734072

The co-genetic evolution of metamorphic core complexes and drainage systems

NASA Astrophysics Data System (ADS)

Trost, Georg; Neubauer, Franz; Robl, Jörg

2016-04-01

Metamorphic core complexes (MCCs) are large scale geological features that globally occur in high strain zones where rocks from lower crustal levels are rapidly exhumed along discrete fault zones, basically ductile-low-angle normal faults recognizable by a metamorphic break between the cool upper plate and hot lower plate. Standard methods, structural analysis and geochronology, are applied to reveal the geodynamic setting of MCCs and to constrain timing and rates of their exhumation. Exhumation is abundantly accompanied by spatially and temporally variable vertical (uplift) and horizontal motions (lateral advection) representing the tectonic driver of topography formation that forces drainage systems and related hillslopes to adjust. The drainage pattern commonly develops in the final stage of exhumation and contributes to the decay of the forming topography. Astonishingly, drainage systems and their characteristic metrics (e.g. normalized steepness index) in regions coined by MCCs have only been sparsely investigated to determine distinctions between different MCC-types (A- and B-type MCCs according to Le Pourhiet et al., 2012). They however, should significantly differ in their topographic expression that evolves by the interplay of tectonic forcing and erosional surface processes. A-type MCCs develop in an overall extensional regime and are bounded partly by strike-slip faults showing transtensional or transpressional components. B-type MCCs are influenced by extensional dynamics only. Here, we introduce C-type MCCs that are updoming along oversteps of crustal-scale, often orogen-parallel strike-slip shear zones. In this study, we analyze drainage systems of several prominent MCCs, and compare their drainage patterns and channel metrics to constrain their geodynamic setting. The Naxos MCC represents an A-type MCC. The Dayman Dome located in Papua New Guinea a B-type MCC, whereas MCCs of the Red River Shear Zone, the Diancang, Ailao-Shan and Day Nui Con Voi complexes, show structural features of the C-type endmember. In the case of the Diancang complex, the MCC is even superimposed by late stage B-type dynamics. The Tauern window and Lepontine dome in the Alps are described as C-type MCCs. We extracted drainage systems and basins and calculated Strahler orders to explore asymmetries in the drainage pattern and to detect evidence for horizontal advection of rivers and catchments. We computed longitudinal river profiles and determined the normalized steepness indexes for channels to uncover regions of spatially variable uplift rates and to constrain the state of landscape adjustment at active MCCs. Furthermore, we analyzed the stability of watersheds by computing so called χ-maps. A-type MCCs show a drainage pattern, which is partly parallel to the stretching and elongation direction, potentially developing from grooves of the detachment. The B-type MCCs show preferences for a radial oriented drainage pattern along lateral terminations. The radial morphology is overprinted by fault systems and neighboring uplifted domes beside the investigation site. A clear preferred direction for further capturing of catchments can be described along detachment zones. The results show an asymmetric alignment of the drainage networks of C-type MCCs, caused by tilting and lateral offset of the streams. One side of the valley shows short streams, whereas the other side is characterized by long, deeply incised streams with a clear tendency to capture adjacent catchments. In C-type MCCs, the drainage pattern develops perpendicular to the trunk streams, which are subparallel to confining faults. The tributaries of the trunk valleys show often dragging in shear direction of the confining fault. The drainage pattern along ductile low-angle normal faults seemingly develops parallel to these faults and shows an asymmetry due to tilting towards the hangingwall block. The analysis reveals that the three types of MCCs can be distinguished by their drainage pattern. All three types have a distinct central drainage divide in common, which is getting elongated in the stretching direction in C-type MCCs and remains small in B-type MCCs. Further early results of our analysis show the high potential of employing morphometric tools in combination with methods from structural geology and low temperature geochronology to determine the type of MCCs, to reveal timing and rates of uplift and horizontal advection, and to constrain the state of landscape adjustment at active MCCs.

The Effects Of Urban Landscape Patterns On Rainfall-Runoff Processes At Small Scale

NASA Astrophysics Data System (ADS)

Chen, L.

2016-12-01

Many studies have indicated that urban landscape change may alter rainfall-runoff processes. However, how urban landscape pattern affect this process is little addressed. In this study, the hydrological effects of landscape pattern on rainfall-runoff processes at small-scale was explored. Twelve residential blocks with independent drainage systems in Beijing were selected as case study areas. Impervious metrics of these blocks, i.e., total impervious area (TIA) and directly connected impervious area (DCIA), were identified. A drainage index describing catchment general drainage load and the overland flow distance, Ad, was estimated and used as one of the landscape spatial metrics. Three scenarios were designed to test the potential influence of impervious surface pattern on runoff processes. Runoff variables including total and peak runoff depth (Qt and Qp) were simulated under different rainfall conditions by Storm Water Management Model (SWMM). The relationship between landscape patterns and runoff variables were analyzed, and further among the three scenarios. The results demonstrated that, in small urban blocks, spatial patterns have inherent influences on rainfall-runoff processes. Specifically, (1) Imperviousness acts as effective indicators in predicting both Qt and Qp. As rainfall intensity increases, the major affecting factor changes from DCIA to TIA for both Qt and Qp; (2) Increasing the size of drainage area dominated by each drainage inlet will benefit the block peak flow mitigation; (3) Different spatial concentrations of impervious surfaces have inherent influences on Qp, when impervious surfaces located away from the outlet can reduce the peak flow discharge. These findings may provide insights into the role of urban landscape patterns in driving rainfall-runoff responses in urbanization, which is essential for urban planning and stormwater management.

[Simulation on contamination forecast and control of groundwater in a certain hazardous waste landfill].

PubMed

Ma, Zhi-Fei; An, Da; Jiang, Yong-Hai; Xi, Bei-Dou; Li, Ding-Long; Zhang, Jin-Bao; Yang, Yu

2012-01-01

On the basis of site investigation and data collection of a certain hazardous waste landfill, the groundwater flow and solute transport coupled models were established by applying Visual Modflow software, which was used to conduct a numerical simulation that forecast the transport process of Cr6+ in groundwater and the effects of three control measures (ground-harden, leakage-proof barriers and drainage ditches) of contaminants transport after leachate leakage happened in impermeable layer of the landfill. The results show that the contamination plume of Cr6+ transports with groundwater flow direction, the contamination rang would reach the pool's boundary in 10 years, and the distance of contamination transport is 1 450 m. But the diffusion range of contamination plume would not be obviously expanded between 10 and 20 years. While the ground is hardened, the contamination plume would not reach the pool's boundary in 20 years. When the leakage-proof barrier is set in the bottom of water table aquifer, the concentration of Cr6+ is higher than that the leakage-proof barrier is unset, but the result is just opposite when setting the leakage-proof barrier in the bottom of underlying aquifer. The range of contamination plume is effectively controlled by setting drainage ditches that water discharge is 2 642 m3 x d(-1), which makes the monitoring wells would not be contaminated in 20 years. Moreover, combining the ground-harden with drainage ditches can get the best effect in controlling contaminants diffusion, and meanwhile, the drainage ditches' daily discharge is reduced to 1 878 m3 x d(-1). Therefore, it is suggested that the control measure combining the ground-harden with drainage ditches should apply to prevent contamination diffusion in groundwater when leachate leakage have happened in impermeable layer of the landfill.

Videothoracoscopic surgery before and after chest tube drainage for children with complicated parapneumonic effusion.

PubMed

Knebel, Rogerio; Fraga, Jose Carlos; Amantea, Sergio Luis; Isolan, Paola Brolin Santis

To evaluate the effectiveness of videothoracoscopic surgery in the treatment of complicated parapneumonic pleural effusion and to determine whether there is a difference in the videothoracoscopic surgery outcome before or after the chest tube drainage. The medical records of 79 children (mean age 35 months) undergoing videothoracoscopic surgery from January 2000 to December 2011 were retrospectively reviewed. The same treatment algorithm was used in the management of all patients. Patients were divided into two groups: in group 1, videothoracoscopic surgery was performed as the initial procedure; in group 2, videothoracoscopic surgery was performed after previous chest tube drainage. Videothoracoscopic surgery was effective in 73 children (92.4%); the other six (7.6%) needed another procedure. Sixty patients (75.9%) were submitted directly to videothoracoscopic surgery (group 1) and 19 (24%) primarily underwent chest tube drainage (group 2). Primary videothoracoscopic surgery was associated with a decrease of hospital stay (p=0.05), time to resolution (p=0.024), and time with a chest tube (p<0.001). However, there was no difference between the groups regarding the time until fever resolution, time with a chest tube, and the hospital stay after videothoracoscopic surgery. No differences were observed between groups regarding the need for further surgery and the presence of complications. Videothoracoscopic surgery is a highly effective procedure for treating children with complicated parapneumonic pleural effusion. When videothoracoscopic surgery is indicated in the presence of loculations (stage II or fibrinopurulent), no difference were observed in time of clinical improvement and hospital stay among the patients with or without chest tube drainage before videothoracoscopic surgery. Copyright © 2017 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.

EFFECT OF pH, IONIC STRENGTH, DISSOLVED ORGANIC CARBON, TIME, AND PARTICLE SIZE ON METALS RELEASE FROM MINE DRAINAGE IMPACTED STREAMBED SEDIMENTS

EPA Science Inventory

Acid-mine drainage (AMD) input to a stream typically results in the stream having a reduced pH, increased concentrations of metals and salts, and decreased biological productivity. Removal and/or treatment of these AMD sources is desired to return the impacted stream(s) to initi...

Recovery of Phytophthora species from drainage points and tributaries within two forest stream networks: a preliminary report

Treesearch

J. Hwang; S.W. Oak; S.N. Jeffers

2011-01-01

To evaluate the number of stream sample sites needed to effectively survey a given stream network for species of Phytophthora, two stream networks, Davidson River and Cathey's Creek, in western North Carolina (USA) were studied. One-litre water samples were collected from the terminal drainage points and most of the tributaries in each stream...

The effects of riverine physical complexity on anadromy and genetic diversity in steelhead or rainbow trout Oncorhynchus mykiss around the Pacific Rim.

PubMed

McPhee, M V; Whited, D C; Kuzishchin, K V; Stanford, J A

2014-07-01

This study explored the relationship between riverine physical complexity, as determined from remotely sensed metrics, and anadromy and genetic diversity in steelhead or rainbow trout Oncorhynchus mykiss. The proportion of anadromy (estimated fraction of individuals within a drainage that are anadromous) was correlated with riverine complexity, but this correlation appeared to be driven largely by a confounding negative relationship between drainage area and the proportion of anadromy. Genetic diversity decreased with latitude, was lower in rivers with only non-anadromous individuals and also decreased with an increasing ratio of floodplain area to total drainage area. Anadromy may be less frequent in larger drainages due to the higher cost of migration associated with reaches farther from the ocean, and the negative relationship between genetic diversity and floodplain area may be due to lower effective population size resulting from greater population fluctuations associated with higher rates of habitat turnover. Ultimately, the relationships between riverine physical complexity and migratory life history or genetic diversity probably depend on the spatial scale of analysis. © 2014 The Fisheries Society of the British Isles.

Effects of ground-water chemistry and flow on quality of drainflow in the western San Joaquin Valley, California

USGS Publications Warehouse

Fio, John L.; Leighton, David A.

1994-01-01

Chemical and geohydrologic data were used to assess the effects of regional ground-water flow on the quality of on-farm drainflows in a part of the western San Joaquin Valley, California. Shallow ground water beneath farm fields has been enriched in stable isotopes and salts by partial evaporation from the shallow water table and is being displaced by irrigation, drainage, and regional ground-water flow. Ground-water flow is primarily downward in the study area but can flow upward in some down- slope areas. Transitional areas exist between the downward and upward flow zones, where ground water can move substantial horizontal distances (0.3 to 3.6 kilometers) and can require 10 to 90 years to reach the downslope drainage systems. Simulation of ground-water flow to drainage systems indicates that regional ground water contributes to about 11 percent of annual drainflow. Selenium concentrations in ground water and drainwater are affected by geologic source materials, partial evaporation from a shallow water table, drainage-system, and regional ground-water flow. Temporal variability in drainflow quality is affected in part by the distribution of chemical constituents in ground water and the flow paths to the drainage systems. The mass flux of selenium in drainflows, or load, generally is proportional to flow, and reductions in drainflow quantity should reduce selenium loads over the short-term. Uncertain changes in the distribution of ground-water quality make future changes in drainflow quality difficult to quantify.

The imperiled fish fauna in the Nicaragua Canal zone

PubMed Central

Torres‐Dowdall, Julián; Meyer, Axel

2016-01-01

Abstract Large‐scale infrastructure projects commonly have large effects on the environment. The planned construction of the Nicaragua Canal will irreversibly alter the aquatic environment of Nicaragua in many ways. Two distinct drainage basins (San Juan and Punta Gorda) will be connected and numerous ecosystems will be altered. Considering the project's far‐reaching environmental effects, too few studies on biodiversity have been performed to date. This limits provision of robust environmental impact assessments. We explored the geographic distribution of taxonomic and genetic diversity of freshwater fish species (Poecilia spp., Amatitlania siquia, Hypsophrys nematopus, Brycon guatemalensis, and Roeboides bouchellei) across the Nicaragua Canal zone. We collected population samples in affected areas (San Juan, Punta Gorda, and Escondido drainage basins), investigated species composition of 2 drainage basins and performed genetic analyses (genetic diversity, analysis of molecular variance) based on mitochondrial cytb. Freshwater fish faunas differed substantially between drainage basins (Jaccard similarity = 0.33). Most populations from distinct drainage basins were genetically differentiated. Removing the geographic barrier between these basins will promote biotic homogenization and the loss of unique genetic diversity. We found species in areas where they were not known to exist, including an undescribed, highly distinct clade of live bearing fish (Poecilia). Our results indicate that the Nicaragua Canal likely will have strong impacts on Nicaragua's freshwater biodiversity. However, knowledge about the extent of these impacts is lacking, which highlights the need for more thorough investigations before the environment is altered irreversibly. PMID:27253906

Computed statistics at streamgages, and methods for estimating low-flow frequency statistics and development of regional regression equations for estimating low-flow frequency statistics at ungaged locations in Missouri

USGS Publications Warehouse

Southard, Rodney E.

2013-01-01

The weather and precipitation patterns in Missouri vary considerably from year to year. In 2008, the statewide average rainfall was 57.34 inches and in 2012, the statewide average rainfall was 30.64 inches. This variability in precipitation and resulting streamflow in Missouri underlies the necessity for water managers and users to have reliable streamflow statistics and a means to compute select statistics at ungaged locations for a better understanding of water availability. Knowledge of surface-water availability is dependent on the streamflow data that have been collected and analyzed by the U.S. Geological Survey for more than 100 years at approximately 350 streamgages throughout Missouri. The U.S. Geological Survey, in cooperation with the Missouri Department of Natural Resources, computed streamflow statistics at streamgages through the 2010 water year, defined periods of drought and defined methods to estimate streamflow statistics at ungaged locations, and developed regional regression equations to compute selected streamflow statistics at ungaged locations. Streamflow statistics and flow durations were computed for 532 streamgages in Missouri and in neighboring States of Missouri. For streamgages with more than 10 years of record, Kendall’s tau was computed to evaluate for trends in streamflow data. If trends were detected, the variable length method was used to define the period of no trend. Water years were removed from the dataset from the beginning of the record for a streamgage until no trend was detected. Low-flow frequency statistics were then computed for the entire period of record and for the period of no trend if 10 or more years of record were available for each analysis. Three methods are presented for computing selected streamflow statistics at ungaged locations. The first method uses power curve equations developed for 28 selected streams in Missouri and neighboring States that have multiple streamgages on the same streams. Statistical estimates on one of these streams can be calculated at an ungaged location that has a drainage area that is between 40 percent of the drainage area of the farthest upstream streamgage and within 150 percent of the drainage area of the farthest downstream streamgage along the stream of interest. The second method may be used on any stream with a streamgage that has operated for 10 years or longer and for which anthropogenic effects have not changed the low-flow characteristics at the ungaged location since collection of the streamflow data. A ratio of drainage area of the stream at the ungaged location to the drainage area of the stream at the streamgage was computed to estimate the statistic at the ungaged location. The range of applicability is between 40- and 150-percent of the drainage area of the streamgage, and the ungaged location must be located on the same stream as the streamgage. The third method uses regional regression equations to estimate selected low-flow frequency statistics for unregulated streams in Missouri. This report presents regression equations to estimate frequency statistics for the 10-year recurrence interval and for the N-day durations of 1, 2, 3, 7, 10, 30, and 60 days. Basin and climatic characteristics were computed using geographic information system software and digital geospatial data. A total of 35 characteristics were computed for use in preliminary statewide and regional regression analyses based on existing digital geospatial data and previous studies. Spatial analyses for geographical bias in the predictive accuracy of the regional regression equations defined three low-flow regions with the State representing the three major physiographic provinces in Missouri. Region 1 includes the Central Lowlands, Region 2 includes the Ozark Plateaus, and Region 3 includes the Mississippi Alluvial Plain. A total of 207 streamgages were used in the regression analyses for the regional equations. Of the 207 U.S. Geological Survey streamgages, 77 were located in Region 1, 120 were located in Region 2, and 10 were located in Region 3. Streamgages located outside of Missouri were selected to extend the range of data used for the independent variables in the regression analyses. Streamgages included in the regression analyses had 10 or more years of record and were considered to be affected minimally by anthropogenic activities or trends. Regional regression analyses identified three characteristics as statistically significant for the development of regional equations. For Region 1, drainage area, longest flow path, and streamflow-variability index were statistically significant. The range in the standard error of estimate for Region 1 is 79.6 to 94.2 percent. For Region 2, drainage area and streamflow variability index were statistically significant, and the range in the standard error of estimate is 48.2 to 72.1 percent. For Region 3, drainage area and streamflow-variability index also were statistically significant with a range in the standard error of estimate of 48.1 to 96.2 percent. Limitations on the use of estimating low-flow frequency statistics at ungaged locations are dependent on the method used. The first method outlined for use in Missouri, power curve equations, were developed to estimate the selected statistics for ungaged locations on 28 selected streams with multiple streamgages located on the same stream. A second method uses a drainage-area ratio to compute statistics at an ungaged location using data from a single streamgage on the same stream with 10 or more years of record. Ungaged locations on these streams may use the ratio of the drainage area at an ungaged location to the drainage area at a streamgage location to scale the selected statistic value from the streamgage location to the ungaged location. This method can be used if the drainage area of the ungaged location is within 40 to 150 percent of the streamgage drainage area. The third method is the use of the regional regression equations. The limits for the use of these equations are based on the ranges of the characteristics used as independent variables and that streams must be affected minimally by anthropogenic activities.

Computed tomography of the lacrimal drainage system: retrospective study of 107 cases of dacryostenosis.

PubMed

Francis, I C; Kappagoda, M B; Cole, I E; Bank, L; Dunn, G D

1999-05-01

To evaluate the role of computed tomography in patients with dacryostenosis. One hundred seven cases of dacryostenosis (94 patients) were assessed by thorough clinical and lacrimal history and examination, and lacrimal region computerized tomography (CT). The lacrimal drainage system examination included the state and position of the puncta; Jones testing; lacrimal syringing; and, in the latter half of the study, telescopic nasal endoscopy. The patients were drawn from the hospital outpatients and private office of the operating lacrimal surgeon in this series (I.C.F.). Of the 107 cases, 79 either underwent dacryocystorhinostomy surgery or had this planned. In 14 of the 107 cases (12 patients), preoperative CT led to an alteration of patient management, usually referral to an otolaryngologist for further evaluation or treatment. In addition to the detection of two tumors extrinsic to the sac, conditions such as ethmoiditis, lacrimal sac mucoceles, soft tissue opacity in the nasolacrimal duct, gross nasal polyposis, fungal sinusitis, and a dacryolith were observed by CT. Similar to the role of functional endoscopic sinus surgery in otolaryngology, CT imaging will become increasingly important in the assessment of many patients with symptoms of lacrimal drainage obstruction.

[Microeukaryotic biodiversity in the waste ore samples surrounding an acid mine drainage lake].

PubMed

Li, Si-Yuan; Hao, Chun-Bo; Wang, Li-Hua; Lü, Zheng; Zhang, Li-Na; Liu, Ying; Feng, Chuan-Ping

2013-10-01

The abandoned mineral samples were collected in an acid mine drainage area in Anhui Province. Molecular ecological methods were used to construct 18S rDNA clone libraries after analyzing the main physicochemical parameters, and then the microeukaryotic diversity and community structure in the acid mine drainage area were studied. The results showed that the region was strongly acidic (pH <3), and the concentrations of Fe, SO2-(4), P, NO-(3) -N showed the same trend, all higher in the bare waste ore samples PD and 1 M than in the vegetation covered samples LW and XC. Four eukaryotic phyla were detected in the abandoned mineral samples: Ascomycota, Basidiomycota, Glomeromycota and Arthropoda. Glomeromycota can form an absolute symbiotic relationship with the plant, and it was a key factor for early plant to adapt the terrestrial environment. The biodiversity of the vegetation covered samples LW and XC, which contained Glomeromycota, was much higher than that of the bare abandoned rock samples PD and 1 M. Moreover, many sequences in the libraries were closely related to some isolated strains, which are tolerant to low pH and heavy metals, such as Penicillium purpurogenum, Chaetothyriales sp. and Staninwardia suttonii.

Evidence-based value of subcutaneous surgical wound drainage: the largest systematic review and meta-analysis.

PubMed

Kosins, Aaron M; Scholz, Thomas; Cetinkaya, Mine; Evans, Gregory R D

2013-08-01

The purpose of this study was to determine the evidenced-based value of prophylactic drainage of subcutaneous wounds in surgery. An electronic search was performed. Articles comparing subcutaneous prophylactic drainage with no drainage were identified and classified by level of evidence. If sufficient randomized controlled trials were included, a meta-analysis was performed using the random-effects model. Fifty-two randomized controlled trials were included in the meta-analysis, and subgroups were determined by specific surgical procedures or characteristics (cesarean delivery, abdominal wound, breast reduction, breast biopsy, femoral wound, axillary lymph node dissection, hip and knee arthroplasty, obesity, and clean-contaminated wound). Studies were compared for the following endpoints: hematoma, wound healing issues, seroma, abscess, and infection. Fifty-two studies with a total of 6930 operations were identified as suitable for this analysis. There were 3495 operations in the drain group and 3435 in the no-drain group. Prophylactic subcutaneous drainage offered a statistically significant advantage only for (1) prevention of hematomas in breast biopsy procedures and (2) prevention of seromas in axillary node dissections. In all other procedures studied, drainage did not offer an advantage. Many surgical operations can be performed safely without prophylactic drainage. Surgeons can consider omitting drains after cesarean section, breast reduction, abdominal wounds, femoral wounds, and hip and knee joint replacement. Furthermore, surgeons should consider not placing drains prophylactically in obese patients. However, drain placement following a surgical procedure is the surgeon's choice and can be based on multiple factors beyond the type of procedure being performed or the patient's body habitus. Therapeutic, II.

Chest tube drainage of transudative pleural effusions hastens liberation from mechanical ventilation.

PubMed

Kupfer, Yizhak; Seneviratne, Chanaka; Chawla, Kabu; Ramachandran, Kavan; Tessler, Sidney

2011-03-01

Pleural effusions occur frequently in patients requiring mechanical ventilatory support. Treatment of the precipitating cause and resolution of the pleural effusion may take considerable time. We retrospectively studied the effect of chest tube drainage of transudative pleural effusions on the liberation of patients from mechanical ventilatory support. Patients in the medical ICU (MICU) at Maimonides Medical Center between January 1, 2009, and October 31, 2009, requiring mechanical ventilatory support with a transudative pleural effusion, were studied retrospectively. They were divided into two groups: standard care and standard care plus chest tube drainage. Chest tubes were placed under ultrasound guidance by trained intensivists. Duration of mechanical ventilatory support was the primary end point. Secondary end points included measures of oxygenation, amount of fluid drained, and complications associated with the chest tube. A total of 168 patients were studied; 88 were treated with standard care and 80 underwent chest tube drainage. Total duration of mechanical ventilatory support was significantly shorter for patients who had chest tube drainage: 3.8±0.5 days vs 6.5±1.1 days for the standard group (P=.03). No differences in oxygenation were noted between the two groups. The average amount of fluid drained was 1,220 mL. No significant complications were caused by chest tube drainage. Chest tube drainage of transudative pleural effusions resulted in more rapid liberation from mechanical ventilatory support. It is a very safe procedure when performed under ultrasound guidance by experienced personnel. ClinicalTrials.gov; Identifier: NCT0114285; URL: www.clinicaltrials.gov.

Selenium volatilization in vegetated agricultural drainage sediment from the San Luis Drain, Central California.

PubMed

Bañuelos, G S; Lin, Z-Q; Arroyo, I; Terry, N

2005-09-01

The presence of large amounts of Se-laden agricultural drainage sediment in the San Luis Drain, Central California, poses a serious toxic threat to wildlife in the surrounding environment. Effective management of the drainage sediment becomes a practical challenge because the sediment is polluted with high levels of Se, B, and salts. This two-year field study was conducted to identify the best plant species that are salt and B tolerant and that have a superior ability of volatilizing Se from drainage sediment. The drainage sediment was mixed with clean soil, and vegetated with salado alfalfa (Medicago sativa 'salado'), salado grass (Sporobulus airoides 'salado'), saltgrass-turf (Distichlis spp. 'NYPA Turf'), saltgrass-forage (Distichlis spicata (L.) Greene), cordgrass (Spartina patens 'Flageo'), Leucaenia (Leucaena leucocephola), elephant grass (Pennistum purpureum), or wild type-Brassica (Brassica spp.). Results show that elephant grass produced the greatest amount of biomass and accumulated highest concentrations of B. Highest concentrations of Se, S, and Cl were observed in wild-type Brassica. Biogenic volatilization of Se by plants and soil microbes was greater in summer. Among the treatments, the mean daily rates of Se volatilization (microg Se m(-2)d(-1)) were wild-type Brassica (39) > saltgrass-turf (31) > cordgrass (27) > saltgrass forage (24) > elephant grass (22) > salado grass (21) > leucaenia (19) > salado alfalfa (14) > irrigated bare soil (11) > non-irrigated bare soil (6). Overall, rates of Se volatilization in drainage sediment were relatively low due to high levels of sulfate. To manage Se in drainage sediment by phytoremediation, the biological volatilization process needs to be enhanced substantially under field conditions.

Cytotoxic and genotoxic affects of acid mine drainage on fish Channa punctata (Bloch).

PubMed

Talukdar, B; Kalita, H K; Basumatary, S; Saikia, D J; Sarma, D

2017-10-01

The investigation deals with the effects of Acid Mine Drainage (AMD) of coal mine on fish Channa punctata (Bloch) by examining the incidence of haematological, morphological, histological changes and DNA fragmentation in tissues of C. punctata in laboratory condition. For this study fishes were exposed to 10% of AMD for a period of 30 days. The fusion of the primary and secondary gill lamellae, distortion, loss of alignment, deposition of worn out tissues and mucous on the surface of the lamella in the gills; degeneration of morphological architecture, loss of alignment of tubules, mucous deposition in the kidney; cellular damage, cellular necrosis, extraneous deposition on the surface, pore formation in the liver are some important changes detected by scanning electron microscopy. Fishes of AMD treated group showed gradual significant decrease in TEC, Hb and, increase in TLC and DLC as compared to that of the control. DNA fragmentation observed in kidney of fishes from treated group indicates an intricate pollutant present in the AMD. The high incidence of morphological and histological alterations, haematological changes along with DNA breakage in C. punctata is an evidence of the cytotoxic and genotoxic potential of AMD of coal mines. Copyright © 2017 Elsevier Inc. All rights reserved.

Improving water management practices to reduce nutrient export from rice paddy fields.

PubMed

Zhang, Zhi-Jian; Yao, Ju-Xiang; Wang, Zhao-De; Xu, Xin; Lin, Xian-Yong; Czapar, George F; Zhang, Jian-Ying

2011-01-01

Nitrogen (N) and phosphorus (P) loss from rice paddy fields represents a significant threat to water quality in China. In this project, three irrigation-drainage regimes were compared, including one conventional irrigation-drainage regime, i.e. continuous submergence regime (CSR), and two improved regimes, i.e. the alternating submergence-nonsubmergence regime (ASNR) and the zero-drainage irrigation technology (ZDIT), to seek cost-effective practices for reducing nutrient loss. The data from these comparisons showed that, excluding the nutrient input from irrigation, the net exports of total N and total P via surface field drainage ranged from -3.93 to 2.39 kg ha and 0.17 to 0.95 g ha(-1) under the CSR operation, respectively, while N loss was -2.46 to -2.23 kg ha(-1) and P export was -0.65 to 0.31 kg ha(-1) under the improved regimes. The intensity of P export was positively correlated to the rate of P application. Reducing the draining frequency or postponing the draining operation would shift the ecological role of the paddy field from a nutrient export source to an interception sink when ASNR or the zero-drainage water management was used. In addition, since the rice yields are being guaranteed at no additional cost, the improved irrigation-drainage operations would have economic as well as environmental benefits.

Technique for predicting ground-water discharge to surface coal mines and resulting changes in head

USGS Publications Warehouse

Weiss, L.S.; Galloway, D.L.; Ishii, Audrey L.

1986-01-01

Changes in seepage flux and head (groundwater level) from groundwater drainage into a surface coal mine can be predicted by a technique that considers drainage from the unsaturated zone. The user applies site-specific data to precalculated head and seepage-flux profiles. Groundwater flow through hypothetical aquifer cross sections was simulated using the U.S. Geological Survey finite-difference model, VS2D, which considers variably saturated two-dimensional flow. Conceptual models considered were (1) drainage to a first cut, and (2) drainage to multiple cuts, which includes drainage effects of an area surface mine. Dimensionless head and seepage flux profiles from 246 simulations are presented. Step-by-step instructions and examples are presented. Users are required to know aquifer characteristics and to estimate size and timing of the mine operation at a proposed site. Calculated groundwater drainage to the mine is from one excavated face only. First cut considers confined and unconfined aquifers of a wide range of permeabilities; multiple cuts considers unconfined aquifers of higher permeabilities only. The technique, developed for Illinois coal-mining regions that use area surface mining and evaluated with an actual field example, will be useful in assessing potential hydrologic impacts of mining. Application is limited to hydrogeologic settings and mine operations similar to those considered. Fracture flow, recharge, and leakage are nor considered. (USGS)

Extraction of drainage networks from large terrain datasets using high throughput computing

NASA Astrophysics Data System (ADS)

Gong, Jianya; Xie, Jibo

2009-02-01

Advanced digital photogrammetry and remote sensing technology produces large terrain datasets (LTD). How to process and use these LTD has become a big challenge for GIS users. Extracting drainage networks, which are basic for hydrological applications, from LTD is one of the typical applications of digital terrain analysis (DTA) in geographical information applications. Existing serial drainage algorithms cannot deal with large data volumes in a timely fashion, and few GIS platforms can process LTD beyond the GB size. High throughput computing (HTC), a distributed parallel computing mode, is proposed to improve the efficiency of drainage networks extraction from LTD. Drainage network extraction using HTC involves two key issues: (1) how to decompose the large DEM datasets into independent computing units and (2) how to merge the separate outputs into a final result. A new decomposition method is presented in which the large datasets are partitioned into independent computing units using natural watershed boundaries instead of using regular 1-dimensional (strip-wise) and 2-dimensional (block-wise) decomposition. Because the distribution of drainage networks is strongly related to watershed boundaries, the new decomposition method is more effective and natural. The method to extract natural watershed boundaries was improved by using multi-scale DEMs instead of single-scale DEMs. A HTC environment is employed to test the proposed methods with real datasets.

Understanding relationships among ecosystem services across spatial scales and over time

NASA Astrophysics Data System (ADS)

Qiu, Jiangxiao; Carpenter, Stephen R.; Booth, Eric G.; Motew, Melissa; Zipper, Samuel C.; Kucharik, Christopher J.; Loheide, Steven P., II; Turner, Monica G.

2018-05-01

Sustaining ecosystem services (ES), mitigating their tradeoffs and avoiding unfavorable future trajectories are pressing social-environmental challenges that require enhanced understanding of their relationships across scales. Current knowledge of ES relationships is often constrained to one spatial scale or one snapshot in time. In this research, we integrated biophysical modeling with future scenarios to examine changes in relationships among eight ES indicators from 2001–2070 across three spatial scales—grid cell, subwatershed, and watershed. We focused on the Yahara Watershed (Wisconsin) in the Midwestern United States—an exemplar for many urbanizing agricultural landscapes. Relationships among ES indicators changed over time; some relationships exhibited high interannual variations (e.g. drainage vs. food production, nitrate leaching vs. net ecosystem exchange) and even reversed signs over time (e.g. perennial grass production vs. phosphorus yield). Robust patterns were detected for relationships among some regulating services (e.g. soil retention vs. water quality) across three spatial scales, but other relationships lacked simple scaling rules. This was especially true for relationships of food production vs. water quality, and drainage vs. number of days with runoff >10 mm, which differed substantially across spatial scales. Our results also showed that local tradeoffs between food production and water quality do not necessarily scale up, so reducing local tradeoffs may be insufficient to mitigate such tradeoffs at the watershed scale. We further synthesized these cross-scale patterns into a typology of factors that could drive changes in ES relationships across scales: (1) effects of biophysical connections, (2) effects of dominant drivers, (3) combined effects of biophysical linkages and dominant drivers, and (4) artificial scale effects, and concluded with management implications. Our study highlights the importance of taking a dynamic perspective and accounting for spatial scales in monitoring and management to sustain future ES.

[Extracorporeal ventriculoatrial shunt with the use of one-way ball valve].

PubMed

Kubo, Shigeki; Takimoto, Hiroshi; Hosoi, Kazuki; Toyota, Shingo; Takakura, Shuji; Hayashi, Yasuhiro; Ueno, Masato; Morisako, Toshitaka; Karasawa, Jun; Ninaga, Hideo; Yoshimine, Toshiki

2002-04-01

We developed a simple system of an "extracorporeal" ventriculoatrial (VA) shunt using a one-way ball valve (Acty valve II, Kaneka Medix) to release the patient from postoperative constraint during the ventricular drainage. The system is constructed in such a way that the ventricular drainage tube is connected to the central venous catheter via a one-way valve. The CSF is regulated by using the valve and is diverted into the systemic circulation as in the conventional ventriculoatrial shunt. After 2 or 3 weeks of CSF diversion through the extracorporeal VA shunt, a ventriculoperitoneal shunt is placed if hydrocephalus is apparent by temporary occlusion of the system. We applied this system to 4 patients with hydrocephalus, and we found it useful and free from adverse effects. The patient was freed from physical constraint involved in conventional ventricular drainage and an effective program of early rehabilitation was able to be started.

Effects of real time control of sewer systems on treatment plant performance and receiving water quality.

PubMed

Frehmann, T; Niemann, A; Ustohal, P; Geiger, W F

2002-01-01

Four individual mathematical submodels simulating different subsystems of urban drainage were intercoupled to an integral model. The submodels (for surface runoff, flow in sewer system, wastewater treatment plant and receiving water) were calibrated on the basis of field data measured in an existing urban catchment investigation. Three different strategies for controlling the discharge in the sewer network were defined and implemented in the integral model. The impact of these control measures was quantified by representative immission state-parameters of the receiving water. The results reveal that the effect of a control measure may be ambivalent, depending on the referred component of a complex drainage system. Furthermore, it is demonstrated that the drainage system in the catchment investigation can be considerably optimised towards environmental protection and operation efficiency if an appropriate real time control on the integral scale is applied.

Radionuclide Data and Calculations and Loss-On-Ignition, X-Ray Fluorescence, and ICP-AES Data from Cores in Catchments of the Animas River, Colorado

USGS Publications Warehouse

Church, Stan E.; Rice, Cyndi A.; Marot, Marci E.

2008-01-01

The U.S. Departments of Agriculture and Interior Abandoned Mine Lands (AML) Initiative is focused on the evaluation of the effect of past mining practices on the water quality and the riparian and aquatic habitats of impacted stream reaches downstream from historical mining districts located primarily on Federal lands. This problem is manifest in the eleven western states (west of longitude 102 degrees) where the majority of hardrock mines that had past production are located on Federal lands. In areas of temperate climate and moderate to heavy precipitation, the effects of rapid chemical and physical weathering of sulfides exposed on mine-waste dumps and acidic drainage from mines have resulted in elevated metal concentrations in the stream water and stream-bed sediment. The result of these mineral weathering processes has an unquantified impact on the quality of the water and the aquatic and riparian habitats that may limit their recreational resource value. One of the confounding factors in these studies is the determination of the component of metals derived from hydrothermally altered but unmined portions of these drainage basins. Several watersheds have been studied to evaluate the effects of acid mine drainage and acid rock drainage on the near-surface environment. The Animas River watershed in southwestern Colorado contains a large number of past-producing metal mines that have affected the watershed. Beginning in October 1996, the U.S. Geological Survey (USGS) began a collaborative study of these effects under the USGS-AML Initiative. In this report, we present the radionuclide and geochemical analytical results of sediment coring during 1997-1999 from two cores from oxbow lakes 0.5 mi. upstream from the 32nd Street Bridge near Durango, Colo., and from three cores from beaver ponds within the Mineral Creek drainage basin near Silverton, Colo.

Drainage of malignant ascites: patient selection and perspectives

PubMed Central

Stukan, Maciej

2017-01-01

Malignant ascites (MA) is a sign of advanced cancer and poor prognosis. MA can result in impairment in quality of life (QOL) and significant symptoms. As a supportive treatment, ascites can be drained by paracentesis (PC), percutaneously implanted catheters (tunneled, untunneled, central venous catheters), or peritoneal ports, or peritoneovenous shunts. The aim of this study was to evaluate the effectiveness, safety, and patient-reported outcomes (PRO) of different drainage methods for the management of MA. A systematic review of the literature was performed, and 32 original articles met the inclusion criteria. Patients selected for permanent drain insertion demonstrated symptoms related to MA and had undergone repeated PC. The primary focus of the reviewed articles was procedural safety issues. The rate of technical success of drainage device installation was 100%. Most patients experienced improvements in symptom control after ascites drainage. When analyzed together, 19.7% (255/1297) of patients experienced any complication and 6.2% (81/1297) experienced serious adverse events during MA drainage. Complications were reported for every drainage method; however, the least occurred after PC or central venous catheter, while the most serious occurred after peritoneovenous shunts. Adverse events were as follows: catheter obstruction: 4.4%, infection: 4.1%, leakage: 3.5%, catheter dislodgment: 2.3%, hypotension: 0.6%, injuries during device insertion: 0.6%, renal impairment: 0.5%, electrolyte imbalance: 0.2%, other: 3.6%. PRO and QOL endpoints were available for 12 studies. When PRO were measured using an interview, a significant improvement in symptom control and QOL was reported in almost all patients. Once standardized questionnaires were used, improvements in symptomatic scores and role functioning were observed. Deterioration was observed in cognitive and emotional subscales. MA drainage is a safe and effective method to control symptoms associated with ascites, and should be perceived as a supportive care, that can be applied for those who need it at any time of their cancer trajectory. Patient selection should be performed using a thorough assessment of symptoms and QOL, and should not be delayed. PMID:28442933

Microbial communities in riparian soils of a settling pond for mine drainage treatment.

PubMed

Fan, Miaochun; Lin, Yanbing; Huo, Haibo; Liu, Yang; Zhao, Liang; Wang, Entao; Chen, Weimin; Wei, Gehong

2016-06-01

Mine drainage leads to serious contamination of soil. To assess the effects of mine drainage on microbial communities in riparian soils, we used an Illumina MiSeq platform to explore the soil microbial composition and diversity along a settling pond used for mine drainage treatment. Non-metric multidimensional scaling analysis showed that the microbial communities differed significantly among the four sampling zones (influent, upstream, downstream and effluent), but not seasonally. Constrained analysis of principal coordinates indicated heavy metals (zinc, lead and copper), total sulphur, pH and available potassium significantly influenced the microbial community compositions. Heavy metals were the key determinants separating the influent zone from the other three zones. Lower diversity indices were observed in the influent zone. However, more potential indicator species, related to sulphur and organic matter metabolism were found there, such as the sulphur-oxidizing genera Acidiferrobacter, Thermithiobacillus, Limnobacter, Thioprofundum and Thiovirga, and the sulphur-reducing genera Desulfotomaculum and Desulfobulbus; the organic matter degrading genera, Porphyrobacter and Paucimonas, were also identified. The results indicated that more microorganisms related to sulphur- and carbon-cycles may exist in soils heavily contaminated by mine drainage. Copyright © 2016 Elsevier Ltd. All rights reserved.

Transvaginal Drainage of Pelvic Abscesses and Collections Using Transabdominal Ultrasound Guidance.

PubMed

Ching, Kevin C; Sumkin, Jules H

2015-01-01

Objectives. To evaluate clinical outcomes following transvaginal catheter placement using transabdominal ultrasound guidance for management of pelvic fluid collections. Methods. A retrospective review was performed for all patients who underwent transvaginal catheter drainage of pelvic fluid collections utilizing transabdominal ultrasound guidance between July 2008 and July 2013. 24 consecutive patients were identified and 24 catheters were placed. Results. The mean age of patients was 48.1 years (range = 27-76 y). 88% of collections were postoperative (n = 21), 8% were from pelvic inflammatory disease (n = 2), and 4% were idiopathic (n = 1). Of the 24 patients, 83% of patients (n = 20) had previously undergone a hysterectomy and 1 patient (4%) was pregnant at the time of drainage. The mean volume of initial drainage was 108 mL (range = 5 to 570). Catheters were left in place for an average of 4.3 days (range = 1-17 d). Microbial sampling was performed in all patients with 71% (n = 17) returning a positive culture. All collections were successfully managed percutaneously. There were no technical complications. Conclusions. Transvaginal catheter drainage of pelvic fluid collections using transabdominal ultrasound guidance is a safe and clinically effective procedure. Appropriate percutaneous management can avoid the need for surgery.

WTAQ version 2-A computer program for analysis of aquifer tests in confined and water-table aquifers with alternative representations of drainage from the unsaturated zone

USGS Publications Warehouse

Barlow, Paul M.; Moench, Allen F.

2011-01-01

The computer program WTAQ simulates axial-symmetric flow to a well pumping from a confined or unconfined (water-table) aquifer. WTAQ calculates dimensionless or dimensional drawdowns that can be used with measured drawdown data from aquifer tests to estimate aquifer hydraulic properties. Version 2 of the program, which is described in this report, provides an alternative analytical representation of drainage to water-table aquifers from the unsaturated zone than that which was available in the initial versions of the code. The revised drainage model explicitly accounts for hydraulic characteristics of the unsaturated zone, specifically, the moisture retention and relative hydraulic conductivity of the soil. The revised program also retains the original conceptualizations of drainage from the unsaturated zone that were available with version 1 of the program to provide alternative approaches to simulate the drainage process. Version 2 of the program includes all other simulation capabilities of the first versions, including partial penetration of the pumped well and of observation wells and piezometers, well-bore storage and skin effects at the pumped well, and delayed drawdown response of observation wells and piezometers.

Modeling the effects of tile drain placement on the hydrologic function of farmed prairie wetlands

USGS Publications Warehouse

Werner, Brett; Tracy, John; Johnson, W. Carter; Voldseth, Richard A.; Guntenspergen, Glenn R.; Millett, Bruce

2016-01-01

The early 2000s saw large increases in agricultural tile drainage in the eastern Dakotas of North America. Agricultural practices that drain wetlands directly are sometimes limited by wetland protection programs. Little is known about the impacts of tile drainage beyond the delineated boundaries of wetlands in upland catchments that may be in agricultural production. A series of experiments were conducted using the well-published model WETLANDSCAPE that revealed the potential for wetlands to have significantly shortened surface water inundation periods and lower mean depths when tile is placed in certain locations beyond the wetland boundary. Under the soil conditions found in agricultural areas of South Dakota in North America, wetland hydroperiod was found to be more sensitive to the depth that drain tile is installed relative to the bottom of the wetland basin than to distance-based setbacks. Because tile drainage can change the hydrologic conditions of wetlands, even when deployed in upland catchments, tile drainage plans should be evaluated more closely for the potential impacts they might have on the ecological services that these wetlands currently provide. Future research should investigate further how drainage impacts are affected by climate variability and change.

Percutaneous Treatment of Congenital Splenic Cysts: Drainage and Sclerotherapy with Polidocanol

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

Goktay, A. Yigit, E-mail: yigit.goktay@deu.edu.tr, E-mail: goktayay@superonline.com; Secil, Mustafa; Ozcan, Mehmet Ali

2006-06-15

Congenital 'true' splenic cysts are rare lesions. Therapeutic methods for the management of these lesions have been based on preserving splenic function due to the immunologic role of spleen. We report three different cases of congenital splenic cysts treated by percutaneous drainage and polidocanol sclerotherapy. This less invasive treatment appears to be safe and effective after 6 to 36 months of follow-up.

Factors influencing the distribution of native bull trout and westslope cutthroat trout in western Glacier National Park, Montana

USGS Publications Warehouse

D'Angelo, Vincent S.; Muhlfeld, Clint C.

2013-01-01

The widespread declines of native bull trout (Salvelinus confluentus) and westslope cutthroat trout (Oncorhynchus clarkii lewisi) populations prompted researchers to investigate factors influencing their distribution and status in western Glacier National Park, Montana. We evaluated the association of a suite of abiotic factors (stream width, elevation, gradient, large woody debris density, pool density, August mean stream temperature, reach surface area) with the occurrence (presence or absence) of bull trout and westslope cutthroat trout in 79 stream reaches in five sub-drainages containing glacial lakes. We modeled the occurrence of each species using logistic regression and evaluated competing models using an information theoretic approach. Westslope cutthroat trout were widely distributed (47 of 79 reaches), and there appeared to be no restrictions on their distribution other than physical barriers. Westslope cutthroat trout were most commonly found in relatively warm reaches downstream of lakes and in headwater reaches with large amounts of large woody debris and abundant pools. By contrast, bull trout were infrequently detected (10 of 79 reaches), with 7 of the 10 (70%) detections in sub-drainages that have not been compromised by non-native lake trout (S. namaycush). Bull trout were most often found in cold, low-gradient reaches upstream of glacial lakes. Our results indicate that complex stream habitats in sub-drainages free of non-native species are important to the persistence of native salmonids in western Glacier National Park. Results from this study may help managers monitor and protect important habitats and populations, inform conservation and recovery programs, and guide non-native species suppression efforts in Glacier National Park and elsewhere.

Simultaneous determination of seven multiclass veterinary antibiotics in surface water samples in the Republic of Korea using liquid chromatography with tandem mass spectrometry.

PubMed

Chung, Hyung Suk; Choi, Jeong-Heui; Abd El-Aty, A M; Lee, Young-Jun; Lee, Han Sol; Kim, Sangdon; Jung, Hee-Jung; Kang, Tae-Woo; Shin, Ho-Chul; Shim, Jae-Han

2016-12-01

A simultaneous determination method using solid-phase extraction and liquid chromatography with tandem mass spectrometry was developed to detect and quantify the presence of seven multiclass veterinary antibiotics (13 compounds in total) in surface water samples, which included the effluents of livestock wastewater and sewage treatment plants, as well as the reservoir drainage areas from dense animal farms. The pH of all water samples was adjusted to 2 or 6 before solid-phase extraction using Oasis HLB cartridges. The developed method was fully validated in terms of linearity, method detection limit, method quantitation limit, accuracy, and precision. The linearity of all tested drugs was good, with R 2 determination coefficients ≥ 0.9931. The method detection limits and method quantitation limits were 0.1-74.3 and 0.5-236.6 ng/L, respectively. Accuracy and precision values were 71-120 and 1-17%, respectively. The determination method was successfully applied for monitoring water samples obtained from the Yeongsan River in 2015. The most frequently detected antibiotics were lincomycin (96%), sulfamethazine (90%), sulfamethoxazole (88%), and sulfathiazole (50%); the maximum concentrations of which were 398.9, 1151.3, 533.1, and 307.4 ng/L, respectively. Overall, the greatest numbers and concentrations of detected antibiotics were found in samples from the effluents of livestock wastewater, sewage treatment plants, and reservoir drainage areas. Diverse veterinary antibiotics were present, and their presence was dependent upon the commercial sales and environmental properties of the analytes, the geographical positions of the sampling points, and the origin of the water. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Severe bradycardia and hypotension after connecting negative pressure to the subgaleal drain during craniotomy closure.

PubMed

Karamchandani, K; Chouhan, R S; Bithal, P K; Dash, H H

2006-05-01

Negative pressure drainage systems are often used after craniotomy for evacuation of potential bleeding. There are several reports of haemodynamic disturbances with epidural negative pressure drainage, but such reports are very few for subgaleal drains placed over the bone flap. We report a case in which a patient developed severe cardiovascular disturbances after the vacuum drainage was connected to a subgaleal drain after craniotomy for aneurysm clipping. The patient had no significant cardiac history, had an uneventful intra-operative course and yet developed bradycardia and hypotension, which were reproducible and severe enough to require atropine administration. Anaesthetists must be aware of these effects, so that they can anticipate and treat such complications.

Current Status of Percutaneous Transhepatic Biliary Drainage in Palliation of Malignant Obstructive Jaundice: A Review

PubMed Central

Chandrashekhara, SH; Gamanagatti, S; Singh, Anuradha; Bhatnagar, Sushma

2016-01-01

Malignancies leading to obstructive jaundice present too late to perform surgery with a curative intent. Due to inexorably progressing hyperbilirubinemia with its consequent deleterious effects, drainage needs to established even in advanced cases. Percutaneous transhepatic biliary drainage (PTBD) and endoscopic retrograde cholangiopancreatography (ERCP) are widely used palliative procedures each with its own merits and lacunae. With the current state-of-the-art PTBD technique consequent upon procedural and hardware improvement, it is equaling ERCP regarding technical success and complications. In addition, there is a reduction in immediate procedure-related mortality with proven survival benefit. Nonetheless, it is the only imminent lifesaving procedure in cholangitis and sepsis. PMID:27803558

Mine drainage control - design for reclamation and neutralization

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

Koehrsen, L.G.; Grandt, A.F.

1970-01-01

The Peabody Coal Company Mine Drainage Neutralization Plant at the Will Scarlet mine is a versatile, full-scale facility which should add much new dimension to the science of dealing with this troublesome waste in the next several years. Hopefully, this brief outline will give other persons concerned with the mine drainage neutralization a grasp of the scope of the Peabody Research Program. It is our plan to follow this background presentation in another year with discussion of the effectiveness of the research project and the results that have been achieved. The research project reported herein is supported in part bymore » Federal Water Pollution Control Administration Research and Development Grant 14010 DAX.« less

Three studies using Ceriodaphnia to detect nonpoint sources of metals from mine drainage

USGS Publications Warehouse

Nimmo, Del Wayne R.; Dodson, Max H.; Davies, Patrick H.; Greene, Joseph C.; Kerr, Mark A.

1990-01-01

Since its introduction, Ceriodaphnia dubia, a small planktonic daphnid, has been widely used for biomonitoring point source discharges. This species was also used to determine nonpoint sources of metals and related contaminants in three trout streams in the west where mining activities have been widespread. Along Chalk Creek, Colo., specific tailings (and impacted tributaries) were sources of metals toxic to fish using the water in a hatchery. At stations below extensive mine tailings in the upper Clark Fork River, Mont., drainage was acutely and chronically toxic to daphnids and paralleled reduced or nonexistent populations of trout. In Whitewood Creek, S. Dak., reduced toxicity below a gold mine portended that fish could live in the stream segment previously impaired by the mine. Toxicity downstream revealed a previously unknown nonpoint source of chromium.

Evaluate ERTS imagery for mapping and detection of changes of snowcover on land and on glaciers

NASA Technical Reports Server (NTRS)

Meier, M. F. (Principal Investigator)

1973-01-01

The author has identified the following significant results. The percentage of snow cover area on specific drainage basins was measured from ERTS-1 imagery by video density slicing with a repeatability of 4 percent of the snow covered area. Data from ERTS-1 images of the melt season snow cover in the Thunder Creek drainage basin in the North Cascades were combined with existing hydrologic and meteorologic observations to enable calculations of the time distribution of the water stored in this mountain snowpack. Similar data could be used for frequent updating of expected inflow to reservoirs. Equivalent snowline altitudes were determined from area measurements. Snowline altitudes were also determined by combining enlarged ERTS-1 images with maps. ERTS-1 imagery was also successfully used to measure glacier accumulation area ratios for a small test basin.

The effects of farm management practices on liver fluke prevalence and the current internal parasite control measures employed on Irish dairy farms.

PubMed

Selemetas, Nikolaos; Phelan, Paul; O'Kiely, Padraig; de Waal, Theo

2015-01-30

Fasciolosis caused by Fasciola hepatica is responsible for major production losses in cattle farms. The objectives of this study were to assess the effect of farm management practices on liver fluke prevalence on Irish dairy farms and to document the current control measures against parasitic diseases. In total, 369 dairy farms throughout Ireland were sampled from October to December 2013, each providing a single bulk tank milk (BTM) sample for liver fluke antibody-detection ELISA testing and completing a questionnaire on their farm management. The analysis of samples showed that cows on 78% (n=288) of dairy farms had been exposed to liver fluke. There was a difference (P<0.05) between farms where cows were positive or negative for liver fluke antibodies in (a) the total number of adult dairy cows in herds, (b) the number of adult dairy cows contributing to BTM samples, and (c) the size of the total area of grassland, with positive farms having larger numbers in each case. There was no difference (P>0.05) between positive and negative farms in (a) the grazing of dry cows together with replacement cows, (b) whether or not grazed grassland was mowed for conservation, (c) the type of drinking water provision system, (d) spreading of cattle manure on grassland or (e) for grazing season length (GSL; mean=262.5 days). Also, there were differences (P<0.001) between drainage statuses for GSL with farms on good drainage having longer GSL than moderately drained farms. The GSL for dairy cows on farms with good drainage was 11 days longer than for those with moderate drainage (P<0.001). The percentage of farmers that used an active ingredient during the non-lactating period against liver fluke, gastrointestinal nematodes, lungworm, and rumen fluke was 96%, 85%, 77% and 90%, respectively. Albendazole was the most frequently used active ingredient for treatment against gastrointestinal nematodes (57%), liver fluke (40%) and lungworm (47%), respectively. There was a difference (P<0.05) in the use of triclabendazole and albendazole between positive and negative farms, with triclabendazole use being more common in positive farms. This study highlighted differences in dairy management practices between Irish farms with dairy herds exposed or not exposed to liver fluke and stressed the need of fine-scale mapping of the disease patterns even at farm level to increase the accuracy of risk models. Also, comprehensive advice and professional support services to farmers on appropriate farm management practices are very important for an effective anthelmintic control strategy. Copyright © 2014 Elsevier B.V. All rights reserved.

The strategies of local farmers' water management and the eco-hydrological effects of irrigation-drainage engineering systems in world heritage of Honghe Hani Rice Terraces

NASA Astrophysics Data System (ADS)

Gao, Xuan

2017-04-01

Terraces are built in mountainous regions to provide larger area for cultivation,in which the hydrological and geomorphological processes are impacted by local farmers' water management strategies and are modified by manmade irrigation-drainage engineering systems.The Honghe Hani Rice Terraces is a 1300a history of traditional agricultural landscape that was inscribed in the 2013 World Heritage List.The local farmers had developed systematic water management strategies and built perfect irrigation-drainage engineering systems to adapt the local rainfall pattern and rice farming activities.Through field investigation,interviews,combined with Geographic Information Systems,Remote Sensing images and Global Positioning Systems technology,the water management strategies as well as the irrigation-drainage systems and their impacts on eco-hydrological process were studied,the results indicate:Firstly,the local people created and maintained an unique woodcarving allocating management system of irrigating water over hundreds years,which aids distributing water and natural nutrition to each terrace field evenly,and regularly according to cultivation schedule.Secondly,the management of local people play an essential role in effective irrigation-drainage engineering system.A ditch leader takes charge of managing the ditch of their village,keeping ample amount of irrigation water,repairing broken parts of ditches,dealing with unfair water using issues,and so on.Meanwhile,some traditional leaders of minority also take part in.Thus, this traditional way of irrigation-drainage engineering has bringed Hani people around 1300 years of rice harvest for its eco-hydrological effects.Lastly we discuss the future of Honghe Hani Rice Terraces,the traditional cultivation pattern has been influenced by the rapid development of modern civilization,in which some related changes such as the new equipment of county roads and plastic channels and the water overusing by tourism are not totally rely on eco-hydrological engineering rules,which broke the ecosystem stability of agricultural terraces.The current situation of Honghe Hani Rice Terraces heritage cannot completely meets the purpose of sustainability development and appropriate conservation of Honghe Hani Rice Terraces heritage.This study of traditional cultivation pattern can help us to propose rational solutions for future development of terraces heritages. Key words:Honghe Hani Rice Terraces,water management,eco-hydrological effects,heritage conservation

Infeasibility of endoscopic transmural drainage due to pancreatic pseudocyst wall calcifications - case report.

PubMed

Krajewski, Andrzej; Lech, Gustaw; Makiewicz, Marcin; Kluciński, Andrzej; Wojtasik, Monika; Kozieł, Sławomir; Słodkowski, Maciej

2017-02-28

Postinflammatory pancreatic pseudocysts are one of the most common complications of acute pancreatitis. In most cases, pseudocysts self-absorb in the course of treatment of pancreatitis. In some patients, pancreatic pseudocysts are symptomatic and cause pain, problems with gastrointestinal transit, and other complications. In such cases, drainage or resection should be performed. Among the invasive methods, mini invasive procedures like endoscopic transmural drainage through the wall of the stomach or duodenum play an important role. For endoscopic transmural drainage, it is necessary that the cyst wall adheres to the stomach or duodenum, making a visible impression. We present a very rare case of infeasibility of endoscopic drainage of a postinflammatory pancreatic pseudocyst, impressing the stomach, due to cyst wall calcifications. A 55-year-old man after acute pancreatitis presented with a 1-year history of epigastric pain and was admitted due to a postinflammatory pseudocyst in the body and tail of pancreas. On admission, blood tests, including CA 19-9 and CEA, were normal. An ultrasound examination revealed a 100-mm pseudocyst in the tail of pancreas, which was confirmed on CT and EUS. Acoustic shadowing caused by cyst wall calcifications made the cyst unavailable to ultrasound assessment and percutaneous drainage. Gastroscopy revealed an impression on the stomach wall from the outside. The patient was scheduled for endoscopic transmural drainage. After insufflation of the stomach, a large mass protruding from the wall was observed. The stomach mucosa was punctured with a cystotome needle knife, and the pancreatic cyst wall was reached. Due to cyst wall calcifications, endoscopic drainage of the cyst was unfeasible. Profuse submucosal bleeding at the puncture site was stopped by placing clips. The patient was scheduled for open surgery, and distal pancreatectomy with splenectomy was performed. The histopathological examination confirmed the initial diagnosis of postinflammatory pancreatic pseudocyst. Endoscopic transmural drainage is a highly effective procedure for treating postinflammatory pancreatic pseudocysts. In some patents, especially with large pseudocysts, pseudocysts with calcified walls, and cysts of primary origin, resection should be performed.

Accumulation of steroid hormones in soil and its adjacent aquatic environment from a typical intensive vegetable cultivation of North China.

PubMed

Zhang, Feng-Song; Xie, Yun-Feng; Li, Xue-Wen; Wang, Dai-Yi; Yang, Lin-Sheng; Nie, Zhi-Qiang

2015-12-15

Steroid hormones released from manure agricultural application are a matter of global concern. The residual levels of steroid hormones were studied in a typical intensive vegetable cultivation area in northeast China, with a long history of heavy manure application. Seven steroids (estrone, 17α-estradiol, 17β-estradiol, estriol, testosterone, androstendione and progesterone) were analyzed from soil sampled from vegetable greenhouses, from sediments and water from the adjacent drainage ditch and from the groundwater. The results showed that target steroids were detected in the soil samples, with detection frequencies varying from 3.13 to 100%. The steroid concentrations varied substantially in soils, ranging from below the detection limit to 109.7μg·kg(-1). Three steroids-progesterone, androstendione and estrone-were found to have relatively high residue concentrations in soil, with maximum concentrations of 109.7, 9.83 and 13.30μg·kg(-1), respectively. In adjacent groundwater, all the steroids, with the exception of estrone, were detected in one or more of the 13 groundwater samples. The concentrations of steroids in groundwater ranged from below the method detection limit to 2.38ng·L(-1). Six of the seven (excluding androstendione) were detected in drainage ditch water samples, with concentrations ranging from below the detection limit to 14ng·L(-1). Progesterone, androstendione and estrone accumulated relatively easily in soils; their concentrations in groundwater were lower than those of other steroids. The concentrations of testosterone and estriol were relatively low in soil, while in groundwater were higher than those of other steroids. The residual levels of steroids in soil and groundwater showed a clear spatial variation in the study area. The residual levels of steroid hormones in soil varied substantially between differently planted greenhouses. Copyright © 2015. Published by Elsevier B.V.

Pesticides detected in surface waters and fish of the Red River of the North drainage basin

USGS Publications Warehouse

Brigham, Mark E.

1994-01-01

Pesticide data have been collected in the Red River Basin by various Federal, State, and local agencies. Tornes and Brigham (1994) recently summarized many of these historical data. This paper summarizes selected data collected as part of the NAWQA program during 1992-93, and briefly compares these data to historical data and to pesticide usage.

Rye cover crop and gamagrass strip effects on NO3 concentration and load in tile drainage.

PubMed

Kaspar, T C; Jaynes, D B; Parkin, T B; Moorman, T B

2007-01-01

A significant portion of the NO3 from agricultural fields that contaminates surface waters in the Midwest Corn Belt is transported to streams or rivers by subsurface drainage systems or "tiles." Previous research has shown that N fertilizer management alone is not sufficient for reducing NO3 concentrations in subsurface drainage to acceptable levels; therefore, additional approaches need to be devised. We compared two cropping system modifications for NO3 concentration and load in subsurface drainage water for a no-till corn (Zea mays L.)-soybean (Glycine max [L.] Merr.) management system. In one treatment, eastern gamagrass (Tripsacum dactyloides L.) was grown in permanent 3.05-m-wide strips above the tiles. For the second treatment, a rye (Secale cereale L.) winter cover crop was seeded over the entire plot area each year near harvest and chemically killed before planting the following spring. Twelve 30.5x42.7-m subsurface-drained field plots were established in 1999 with an automated system for measuring tile flow and collecting flow-weighted samples. Both treatments and a control were initiated in 2000 and replicated four times. Full establishment of both treatments did not occur until fall 2001 because of dry conditions. Treatment comparisons were conducted from 2002 through 2005. The rye cover crop treatment significantly reduced subsurface drainage water flow-weighted NO3 concentrations and NO3 loads in all 4 yr. The rye cover crop treatment did not significantly reduce cumulative annual drainage. Averaged over 4 yr, the rye cover crop reduced flow-weighted NO3 concentrations by 59% and loads by 61%. The gamagrass strips did not significantly reduce cumulative drainage, the average annual flow-weighted NO3 concentrations, or cumulative NO3 loads averaged over the 4 yr. Rye winter cover crops grown after corn and soybean have the potential to reduce the NO3 concentrations and loads delivered to surface waters by subsurface drainage systems.

A Systematic Review and Meta-Analysis Comparing Pigtail Catheter and Chest Tube as the Initial Treatment for Pneumothorax.

PubMed

Chang, Su-Huan; Kang, Yi-No; Chiu, Hsin-Yi; Chiu, Yu-Han

2018-05-01

The optimal initial treatment approach for pneumothorax remains controversial. This systemic review and meta-analysis investigated the effectiveness of small-bore pigtail catheter (PC) drainage compared with that of large-bore chest tube (LBCT) drainage as the initial treatment approach for all subtypes of pneumothorax. PubMed and Embase were systematically searched for observational studies and randomized controlled trials published up to October 9, 2017, that compared PC and LBCT as the initial treatment for pneumothorax. The investigative outcomes included success rates, recurrence rates, complication rates, drainage duration, and hospital stay. Of the 11 included studies (875 patients), the success rate was similar in the PC (79.84%) and LBCT (82.87%) groups, with a risk ratio of 0.99 (95% CI, 0.93 to 1.05; I 2  = 0%). Specifically, PC drainage was associated with a significantly lower complication rate following spontaneous pneumothorax than LBCT drainage (Peto odds ratio: 0.49 [95% CI, 0.28 to 0.85]; I 2  = 29%). In the spontaneous subgroup, PC drainage was associated with a significantly shorter drainage duration (mean difference, -1.51 [95% CI, -2.93 to -0.09]) and hospital stay (mean difference: -2.54 [95% CI, -3.16 to -1.92]; P < .001) than the LBCT group. Collectively, results of the meta-analysis suggest PC drainage may be considered as the initial treatment option for patients with primary or secondary spontaneous pneumothorax. Ideally, randomized controlled trials are needed to compare PC vs LBCT among different subgroups of patients with pneumothorax, which may ultimately improve clinical care and management for these patients. PROSPERO; No.: CRD42017078481; URL: https://www.crd.york.ac.uk/prospero/. Copyright © 2018 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.

A Novel Uncultured Bacterium of the Family Gallionellaceae: Description and Genome Reconstruction Based on the Metagenomic Analysis of Microbial Community in Acid Mine Drainage.

PubMed

Kadnikov, V V; Ivasenko, D A; Beletsky, A V; Mardanov, A V; Danilova, E V; Pimenov, N V; Karnachuk, O V; Ravin, N V

2016-07-01

Drainage waters at the metal mining areas often have low pH and high content of dissolved metals due to oxidation of sulfide minerals. Extreme conditions limit microbial diversity in- such ecosystems. A drainage water microbial community (6.5'C, pH 2.65) in an open pit at the Sherlovaya Gora polymetallic open-cast mine (Transbaikal region, Eastern Siberia, Russia) was studied using metagenomic techniques. Metagenome sequencing provided information for taxonomic and functional characterization of the micro- bial community. The majority of microorganisms belonged to a single uncultured lineage representing a new Betaproteobacteria species of the genus Gallionella. While no.acidophiles are known among the cultured members of the family Gallionellaceae, similar 16S rRNA gene sequences were detected in acid mine drain- ages. Bacteria ofthe genera Thiobacillus, Acidobacterium, Acidisphaera, and Acidithiobacillus,-which are com- mon in acid mine drainage environments, were the minor components of the community. Metagenomic data were -used to determine the almost complete (-3.4 Mb) composite genome of the new bacterial. lineage desig- nated Candidatus Gallionella acididurans ShG14-8. Genome analysis revealed that Fe(II) oxidation probably involved the cytochromes localized on the outer membrane of the cell. The electron transport chain included NADH dehydrogenase, a cytochrome bc1 complex, an alternative complex III, and cytochrome oxidases of the bd, cbb3, and bo3 types. Oxidation of reduced sulfur compounds probably involved the Sox system, sul- fide-quinone oxidoreductase, adenyl sulfate reductase, and sulfate adenyltransferase. The genes required for autotrophic carbon assimilation via the Calvin cycle were present, while no pathway for nitrogen fixation was revealed. High numbers of RND metal transporters and P type ATPases were probably responsible for resis- tance to heavy metals. The new microorganism was an aerobic chemolithoautotroph of the group of psychrotolerant iron- and sulfur-oxidizing acidophiles of the family Gallionellaceae, which are common in acid mine drainages.

Lymphatic Drainage from Renal Tumors In Vivo: A Prospective Sentinel Node Study Using SPECT/CT Imaging.

PubMed

Kuusk, Teele; De Bruijn, Roderick; Brouwer, Oscar R; De Jong, Jeroen; Donswijk, Maarten; Grivas, Nikolaos; Hendricksen, Kees; Horenblas, Simon; Prevoo, Warner; Valdés Olmos, Renato A; Van Der Poel, Henk G; Van Rhijn, Bas W G; Wit, Esther M; Bex, Axel

2018-06-01

Lymphatic drainage from renal tumors is unpredictable. In vivo drainage studies of primary lymphatic landing sites may reveal the variability and dynamics of lymphatic connections. The purpose of this study was to investigate the lymphatic drainage pattern of renal tumors in vivo with single photon emission/computerized tomography after intratumor radiotracer injection. We performed a phase II, prospective, single arm study to investigate the distribution of sentinel nodes from renal tumors on single photon emission/computerized tomography. Patients with cT1-3 (less than 10 cm) cN0M0 renal tumors of any subtype were enrolled in analysis. After intratumor ultrasound guided injection of 0.4 ml 99m Tc-nanocolloid we performed preoperative imaging of sentinel nodes with lymphoscintigraphy and single photon emission/computerized tomography. Sentinel and locoregional nonsentinel nodes were resected with a γ probe combined with a mobile γ camera. The primary study end point was the location of sentinel nodes outside the locoregional retroperitoneal templates on single photon emission/computerized tomography. Using a Simon minimax 2-stage design to detect a 25% extralocoregional retroperitoneal template location of sentinel nodes on imaging at α = 0.05 and 80% power at least 40 patients with sentinel node imaging on single photon emission/computerized tomography were needed. Of the 68 patients 40 underwent preoperative single photon emission/computerized tomography of sentinel nodes and were included in primary end point analysis. Lymphatic drainage outside the locoregional retroperitoneal templates was observed in 14 patients (35%). Eight patients (20%) had supradiaphragmatic sentinel nodes. Sentinel nodes from renal tumors were mainly located in the respective locoregional retroperitoneal templates. Simultaneous sentinel nodes were located outside the suggested lymph node dissection templates, including supradiaphragmatic sentinel nodes in more than a third of the patients. Copyright © 2018 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

Crizotinib-induced Rectal Perforation with Abscess.

PubMed

Yanagisawa, Asako; Hayama, Noriko; Amano, Hiroyuki; Nakamura, Makoto; Hirano, Satoshi; Nakamura, Sukeyuki; Tabeta, Hiroshi

2017-12-01

An 86-year-old Japanese man was diagnosed with stage IV lung adenocarcinoma. The patient was treated with crizotinib after echinoderm microtubule-associated protein-like 4 (EML4)-anaplastic lymphoma kinase (ALK) rearrangement was detected from his pleural effusion. He subsequently developed abdominal pain and rebound tenderness in the right lower abdomen. Contrast-enhanced abdominal CT showed a low-density area in the abdominal cavity. The size of the abscess was decreased by drainage and the administration of antibiotics. Fistulography revealed a fistula from the rectum to the abscess, and a diagnosis of lower intestinal tract perforation with abscess formation was made. Crizotinib was discontinued and treatment with alectinib was initiated. The patient remains under treatment as an outpatient at our department without adverse effects.

Crizotinib-induced Rectal Perforation with Abscess

PubMed Central

Yanagisawa, Asako; Hayama, Noriko; Amano, Hiroyuki; Nakamura, Makoto; Hirano, Satoshi; Nakamura, Sukeyuki; Tabeta, Hiroshi

2017-01-01

An 86-year-old Japanese man was diagnosed with stage IV lung adenocarcinoma. The patient was treated with crizotinib after echinoderm microtubule-associated protein-like 4 (EML4)-anaplastic lymphoma kinase (ALK) rearrangement was detected from his pleural effusion. He subsequently developed abdominal pain and rebound tenderness in the right lower abdomen. Contrast-enhanced abdominal CT showed a low-density area in the abdominal cavity. The size of the abscess was decreased by drainage and the administration of antibiotics. Fistulography revealed a fistula from the rectum to the abscess, and a diagnosis of lower intestinal tract perforation with abscess formation was made. Crizotinib was discontinued and treatment with alectinib was initiated. The patient remains under treatment as an outpatient at our department without adverse effects. PMID:29021430

Evaluation of the sustainability of road drainage systems

NASA Astrophysics Data System (ADS)

García-Diez, Iván; Palencia, Covadonga; Fernández Raga, María

2017-04-01

Water is the most erosive agent that exists on the linear structures, because they are constantly subjected to outdoor condition like irregular infiltration, frosts and different rain intensities. Another variables that highly influence in the entire lifetime of a natural drainage system are the spatial and temporal variability of the rainfall, the soil, the vegetation cover and the design. All this factors are affecting the vulnerability of the clearings and embankments, by wearing away the weakest materials which surround the roads or train rails, producing erosion and very bumpy surfaces. The result is that the original pattern, developped to disminished the lost of soil, is not properly working and it cannot eliminate water, with the consequence destruction of the linear structure after several rainfall periods, and the accumulation of material down slope. The propose of this research focuses on analysing the drainage systems used in spanish roads and railways lines. For this purpose, a revision of the literature has been done, and the main drainage solutions have been recovered, carrying out an evaluation of them from an environmental point of view. This procedure has been requested by several authors in the past (Nwa, E.U. & Twocock, J.G., 1969; Goulter, I.C., 1992), together with the need of designing a more sustainable drainage system. The final objective of this complete revision is to compare objetively the designs to valuate them in order to develop a new drainage patter which minimize the erosion, increasing the durability and effectiveness of the drainage system. For this purpose, it is neccesary to assure that all the systems will be compare under similar parameters of flow rate, vegetation, substrate, lenght, slope and total section. Only the channels pattern and water distribution will change. The analysis has been done following Liu, H. & Zhu, X.B., (2012), who pointed out that the main parameters to take into account to select a road drainage system are the hydraulic functioning, structural strength, produced erosion, service life, initial invesment and maintenance costs of different drainage systems. The followed methodology was to create a Leopold's matrix to compare among the alternatives of drainage design, asignating a puntuation from 1 to 5 to each factor that affects the functioning of the drainage. The process to decide the punctuation of every factor in each drainage design will be also explained. The alternative which obtains more puntuation represents the best available design to decrease erosion on the slopes and increase the service life. The validation of this results has been done in the field. References Goulter, I.C., 1992. Systems Analysis in Water-Distribution Network Design: From Theory to Practice, Journal of Water Resources Planning and Management. ASCE 118, No. 3 Nwa, E.U. & Twocock, J.G., 1969. Drainage design theory and practice. Journal of Hydrology 9, 259-276 Liu, H. & Zhu, X.B., 2012. Influencing Factors and Prevention Measures of Erosion Damage for Highway Slope in Loess Area. Advanced Materials Research 594, 161-166

The efficacy and safety of burr-hole craniotomy without continuous drainage for chronic subdural hematoma and subdural hygroma in children under 2 years of age.

PubMed

Matsuo, Kazuya; Akutsu, Nobuyuki; Otsuka, Kunitoshi; Yamamoto, Kazuki; Kawamura, Atsufumi; Nagashima, Tatsuya

2016-12-01

Various treatment modalities have been used in the management of chronic subdural hematoma and subdural hygroma (CSDH/SDHy) in children. However, few studies have examined burr-hole craniotomy without continuous drainage in such cases. Here, we retrospectively evaluated the efficacy and safety of burr-hole craniotomy without continuous drainage for CSDH/SDHy in children under 2 years old. We also aimed to determine the predictors of CSDH/SDHy recurrence. We conducted a retrospective chart review of 25 children under 2 years old who underwent burr-hole craniotomy without continuous drainage for CSDH/SDHy at a pediatric teaching hospital over a 10-year period. We analyzed the relationship between CSDH/SDHy recurrence and factors such as abusive head trauma, laterality of CSDH/SDHy, and subdural fluid collection type (hematoma or hygroma). CSDH/SDHy recurred in 5 of the 25 patients (20 %), requiring a second operation at an average of 0.92 ± 1.12 months after the initial procedure. The mean follow-up period was 25.1 ± 28.6 months. There were no complications related to either operation. None of the assessed factors were statistically associated with recurrence. Burr-hole craniotomy without continuous drainage for CSDH/SDHy appears safe in children aged under 2 years and results in a relatively low recurrence rate. No predictors of CSDH/SDHy recurrence were identified. Advantages of this method include avoiding external subdural drainage-related complications. However, burr-hole drainage may be more effective for CSDH, which our data suggests is more likely to recur than SDHy, providing the procedure is performed with specific efforts to reduce complications.

Management of colorectal emergencies: percutaneous abscess drainage.

PubMed

Brusciano, L; Maffettone, V; Napolitano, V; Izzo, G; Rossetti, G; Izzo, D; Russo, F; Russo, G; del Genio, G; del Genio, A

2004-01-01

Pelvic abscesses represent the most frequent complications of colorectal surgery. Percutaneous CT or US guided drainage can be an alternative to surgical drainage that is associated to a significant mortality rate. In the current study results of PAD, performed in 39 patients with pelvic or abdominopelvic abscesses were reviewed in order to evaluate reliability of such procedure. Major part of the collections 33/39 (85%) developed after resective colorectal surgery, and 20/39 (51%) were associated to anastomotic fistula; 22/39 (56%) were poorly defined; 16/39 (41%) were multiloculated; 16/39 (41%) had a stool contamination, 23/39 (58%) were greater than 10 cm; 14/39 (35%) were multiple. Thirty-five patients (89.7%) healed, despite high number of complex abscesses and complete resolution of sepsis was achieved in 5.1 +/- 2.9 days. CT proved to be the most reliable tool in assessing distinctive features of collections as well as in identifying the best route for drainage. Adequate size of the catheter was essential to get an effective drainage. In particular, large sized catheter (> 20 Fr) had to be used to drain collections associated to anastomotic fistulas with stool contamination. In four elderly neoplastic patients with chronic illnesses (10%), only a single small sized catheter could be positioned, because of patients poor compliance and PAD was inaffective. Nevertheless even those patients got a partial resolution of the sepsis and their general conditions markedly improved, so that they were able to underwent successful surgical drainage. In conclusion PAD is a safe and reliable tool that can be employed as an alternative to surgical drainage at least as first measure, even if complex pelvic abscesses are found.

Postoperative Mortality after Liver Resection for Perihilar Cholangiocarcinoma: Development of a Risk Score and Importance of Biliary Drainage of the Future Liver Remnant

PubMed Central

Wiggers, Jimme K; Koerkamp, Bas Groot; Cieslak, Kasia P; Doussot, Alexandre; van Klaveren, David; Allen, Peter J; Besselink, Marc G; Busch, Olivier R; D’Angelica, Michael I; DeMatteo, Ronald P; Gouma, Dirk J; Kingham, T Peter; van Gulik, Thomas M; Jarnagin, William R

2016-01-01

Background Liver surgery for perihilar cholangiocarcinoma (PHC) is associated with postoperative mortality ranging from 5% to 18%. The aim of this study was to develop a preoperative risk score for postoperative mortality after liver resection for PHC, and to assess the effect of biliary drainage of the future liver remnant (FLR). Study design A consecutive series of 287 patients submitted to major liver resection for presumed PHC between 1997 and 2014 at two Western centers was analyzed; 228 patients (79%) underwent preoperative drainage for jaundice. FLR volumes were calculated with CT volumetry, and completeness of FLR drainage was assessed on imaging. Logistic regression was used to develop a mortality risk score. Results Postoperative mortality at 90-days was 14%, and was independently predicted by age (Odds ratio [OR] per 10 years 2.1), preoperative cholangitis (OR 4.1), FLR volume below 30% (OR 2.9), portal vein reconstruction (OR 2.3), and incomplete FLR drainage in patients with FLR volume below 50% (OR 2.8). The risk score showed good discrimination (AUC 0.75 after bootstrap validation), and ranking patients in tertiles identified three (low-intermediate-high) risk subgroups with predicted mortalities of 2%, 11%, and 37%. No postoperative mortality was observed in 33 undrained patients with FLR volumes above 50%, including 10 jaundiced patients (median bilirubin level 11 mg/dL). Conclusions The mortality risk score for patients with resectable PHC can be used for patient counseling and identification of modifiable risk factors, which include FLR volume, FLR drainage status, and preoperative cholangitis. We found no evidence to support preoperative biliary drainage in patients with an FLR volume above 50%. PMID:27063572

Endoscopic ultrasound-guided placement of plastic vs. biflanged metal stents for therapy of walled-off necrosis: a retrospective single-center series.

PubMed

Mukai, Shuntaro; Itoi, Takao; Baron, Todd H; Sofuni, Atsushi; Itokawa, Fumihide; Kurihara, Toshio; Tsuchiya, Takayoshi; Ishii, Kentaro; Tsuji, Shujiro; Ikeuchi, Nobuhito; Tanaka, Reina; Umeda, Junko; Tonozuka, Ryosuke; Honjo, Mitsuyoshi; Gotoda, Takuji; Moriyasu, Fuminori; Yasuda, Ichiro

2015-01-01

Recently, a novel fully covered and biflanged metal stent (BFMS)dedicated to the drainage of walled-off necrosis(WON) was developed. The aim of this study was to retrospectively evaluate the safety, efficacy, and cost performance of drainage of WON using the novel BFMS compared with a traditional plastic stent. A total of 70 patients with symptomatic WON were treated under endoscopic ultrasound (EUS) guidance. Initial drainage was conducted using the single gateway technique with placement of one or more plastic stents or a single BFMS.If drainage was unsuccessful,direct endoscopic necrosectomy (DEN)was performed. There were no statistically significant differences in rates of technical success, clinical success,and adverse events between plastics stents and BFMS, despite the size of WON in the BFMS group being significantly larger than that in the plastic stent group (105.6 vs. 77.1 mm; P=0.003).The mean procedure times for the first EUS-guided drainage and for re-intervention were significantly shorter in the BFMS group than in the plastic stent group (28.8±7.1 vs. 42.6±14.2, respectively,for drainage, P<0.001; and 34.9±8.5 vs.41.8±7.6, respectively, for re-intervention, P<0.001). There was no statistically significant difference in the total cost between plastic stent and BFMS use in the treatment of WON ($5352vs. $6274; P=0.25). Plastic stents and BFMS were safe and effective for the treatment of WON. In particular,BFMS placement appeared to be preferable for initial EUS-guided drainage and additional reintervention(e.g. DEN) as it reduced the procedure time. Prospective randomized controlled trials are warranted.

A hierarchical pyramid method for managing large-scale high-resolution drainage networks extracted from DEM

NASA Astrophysics Data System (ADS)

Bai, Rui; Tiejian, Li; Huang, Yuefei; Jiaye, Li; Wang, Guangqian; Yin, Dongqin

2015-12-01

The increasing resolution of Digital Elevation Models (DEMs) and the development of drainage network extraction algorithms make it possible to develop high-resolution drainage networks for large river basins. These vector networks contain massive numbers of river reaches with associated geographical features, including topological connections and topographical parameters. These features create challenges for efficient map display and data management. Of particular interest are the requirements of data management for multi-scale hydrological simulations using multi-resolution river networks. In this paper, a hierarchical pyramid method is proposed, which generates coarsened vector drainage networks from the originals iteratively. The method is based on the Horton-Strahler's (H-S) order schema. At each coarsening step, the river reaches with the lowest H-S order are pruned, and their related sub-basins are merged. At the same time, the topological connections and topographical parameters of each coarsened drainage network are inherited from the former level using formulas that are presented in this study. The method was applied to the original drainage networks of a watershed in the Huangfuchuan River basin extracted from a 1-m-resolution airborne LiDAR DEM and applied to the full Yangtze River basin in China, which was extracted from a 30-m-resolution ASTER GDEM. In addition, a map-display and parameter-query web service was published for the Mississippi River basin, and its data were extracted from the 30-m-resolution ASTER GDEM. The results presented in this study indicate that the developed method can effectively manage and display massive amounts of drainage network data and can facilitate multi-scale hydrological simulations.