Maternal anthropometrics are associated with fetal size in different periods of pregnancy and at birth. The Generation R Study.

PubMed

Ay, L; Kruithof, C J; Bakker, R; Steegers, E A P; Witteman, J C M; Moll, H A; Hofman, A; Mackenbach, J P; Hokken-Koelega, A C S; Jaddoe, V W V

2009-06-01

We aimed to examine the associations of maternal anthropometrics with fetal weight measured in different periods of pregnancy and with birth outcomes. Population-based birth cohort study. Data of pregnant women and their children in Rotterdam, the Netherlands. In 8541 mothers, height, prepregnancy body mass index (BMI) and gestational weight gain were available. Fetal growth was measured by ultrasound in mid- and late pregnancy. Regression analyses were used to assess the impact of maternal anthropometrics on fetal weight and birth outcomes. Fetal weight and birth outcomes: weight (grams) and the risks of small (<5th percentile) and large (>95th percentile) size for gestational age at birth. Maternal BMI in pregnancy was positively associated with estimated fetal weight during pregnancy. The effect estimates increased with advancing gestational age. All maternal anthropometrics were positively associated with fetal size (P-values for trend <0.01). Mothers with both their prepregnancy BMI and gestational weight gain quartile in the lowest and highest quartiles showed the highest risks of having a small and large size for gestational age child at birth, respectively. The effect of prepregnancy BMI was strongly modified by gestational weight gain. Fetal growth is positively affected by maternal BMI during pregnancy. Maternal height, prepregnancy BMI and gestational weight gain are all associated with increased risks of small and large size for gestational age at birth in the offspring, with an increased effect when combined.

Effective Delivery of Arsenic Trioxide to HPV-Positive Cervical Cancer Cells Using Optimised Liposomes: A Size and Charge Study.

PubMed

Akhtar, Anam; Wang, Scarlet Xiaoyan; Ghali, Lucy; Bell, Celia; Wen, Xuesong

2018-04-04

Despite the success of arsenic trioxide (ATO) in treating haematological malignancies, its potential to treat solid tumours has not been fully exploited, owing to its dose-limiting toxicity and poor pharmacokinetics. In order to overcome this hurdle, liposomal encapsulation of the drug with different surface charges (neutral, negative, and positive) and sizes (100, 200 and 400 nm) were synthesised and tested on human papilloma virus (HPV)-positive HeLa and HPV-negative HT-3 cervical cancer cell lines. Two epithelial cell lines-human keratinocytes (HK) and human colon cells (CRL-1790)-were used as controls. The synthesised liposomes were tested for their physico-chemical characteristics, drug loading efficiency, and toxicity on the studied cell lines. Neutral liposomes of 100 nm in size were the chosen formulation for delivering ATO into the studied cells, as they showed the least intrinsic cytotoxicity and the highest loading efficiency. The findings demonstrated that the optimised formulation of liposomes was an effective drug delivery method for HPV-infected cervical cancer cells. Furthermore, the toxicity vs. uptake ratio was highest for HeLa cells, while a reduced or minimal toxic effect was observed for non-HPV-infected cervical cancer cells and control cells. These findings may provide a promising therapeutic strategy for effectively managing cervical cancers.

Sorption-desorption of carbamazepine by palygorskite-montmorillonite (PM) filter medium.

PubMed

Berhane, Tedros M; Levy, Jonathan; Krekeler, Mark P S; Danielson, Neil D; Stalcup, Apryll

2015-01-23

Palygorskite-montmorillonite (PM) was studied as a potential sewage treatment effluent filter material for carbamazepine. Batch sorption experiments were conducted as a function of granule size (0.3-0.6, 1.7-2.0 and 2.8mm) and different sewage effluent conditions (pH, ionic strength and temperature). Results showed PM had a mix of fibrous and plate-like morphologies. Sorption and desorption isotherms were fitted to the Freundlich model. Sorption is granule size-dependent and the medium granule size would be an appropriate size for optimizing both flow and carbamazepine retention. Highest and lowest sorption capacities corresponded to the smallest and the largest granule sizes, respectively. The lowest and the highest equilibrium aqueous (Ce) and sorbed (qe) carbamazepine concentrations were 0.4 mg L(-1) and 4.5 mg L(-1), and 0.6 mg kg(-1) and 411.8 mg kg(-1), respectively. Observed higher relative sorption at elevated concentrations with a Freundlich exponent greater than one, indicated cooperative sorption. The sorption-desorption hysteresis (isotherm non-singularity) indicated irreversible sorption. Higher sorption observed at higher rather than at lower ionic strength conditions is likely due to a salting-out effect. Negative free energy and the inverse sorption capacity-temperature relationship indicated the carbamazepine sorption process was favorable or spontaneous. Solution pH had little effect on sorption. Copyright © 2014 Elsevier B.V. All rights reserved.

Effect of bio-column composed of aged refuse on methane abatement--a novel configuration of biological oxidation in refuse landfill.

PubMed

Han, Dan; Zhao, Youcai; Xue, Binjie; Chai, Xiaoli

2010-01-01

An experimental bio-column composed of aged refuse was installed around the exhaust pipe as a new way to mitigate methane in refuse landfill. One of the objectives of this work was to assess the effect of aged refuse thickness in bio-column on reducing CH4 emissions. Over the study period, methane oxidation was observed at various thicknesses, 5 cm (small size), 10 cm (middle size) and 15 cm (large size), representing one to three times of pipeline diameters. The middle and large size both showed over 90% methane conversion, and the highest methane conversion rate of above 95% occurred in the middle-size column cell. Michaelis-Menten equation addressed the methanotrophs diffusion in different layers of the bio-columns. Maximum methanotrophic activity (Vmax) measured at the three thicknesses ranged from 6.4 x 10(-3) to 15.6 x 10(-3) units, and the half-saturation value (K(M)) ranged from 0.85% to 1.67%. Both the highest Vmax and K(M) were observed at the middle-size of the bio-column, as well as the largest methanotrophs population, suggesting a significant efficiency of methane mitigation happened in the optimum zone with greatest affinity and methanotrophic bacteria activities. Therefore, bio-column is a potential style for methane abatement in landfill, and the aged refuse both naturally formed and artificially placed in the column plays a critical role in CH4 emission.

The influence of dietary antioxidant on ovarian eggs and levels of vitamin E, C, A, astaxanthin, β-carotene and oxidative stres in tissues of Astacus leptodactylus (Eschscholtz) during reproduction.

PubMed

Barim-Oz, O; Sahin, H

2016-12-30

The experiment was conducted to determine the most effective antioxidant (among the vitamin E (VE), vitamin C (VC), vitamin A (VA), astaxanthine (AX), β-carotene (βC)) on the ovarian egg number and size, level of VE, VC, VA, AX, βC and oxidative stress (as malondialdehyde (MDA)) in the hepatopancreas, ovarian, gills and muscle tissue during ovarian development of Astacus leptodactylus. One control (C) and five experimental diets (EE, EC, EA, EAX and EβC) were prepared. The EE, EC, EA, EAX and EβC groups were formed by added 150 mg kg-1 VE, 200 mg kg-1 VC, 240 mg kg-1 VA, 200 mg kg-1 AX and 200 mg kg-1 βC to diet C, respectively. At the end of the experiment found that the dietary antioxidants increased ovarian egg number and size and reduced the level of MDA in the tissues. Ovarian egg number and size were highest in the EE and EAX diet groups in the comparison to control (p<0.001). The level of MDA in the tissues was lowest in the EAX diet group in the comparison to control (p<0.001). The highest levels of VE, VC, VA, AX and βC were found in the hepatopancreas and ovarian compared with muscle and gills. The highest level of MDA also was determined in the ovarian according to other tissues. In conclusion, the VE and AX in broodstock diets were the most effective antioxidants on the ovarian egg number and size of A. leptodactylus.

Differential foraging preferences on seed size by rodents result in higher dispersal success of medium-sized seeds.

PubMed

Cao, Lin; Wang, Zhenyu; Yan, Chuan; Chen, Jin; Guo, Cong; Zhang, Zhibin

2016-11-01

Rodent preference for scatter-hoarding large seeds has been widely considered to favor the evolution of large seeds. Previous studies supporting this conclusion were primarily based on observations at earlier stages of seed dispersal, or on a limited sample of successfully established seedlings. Because seed dispersal comprises multiple dispersal stages, we hypothesized that differential foraging preference on seed size by animal dispersers at different dispersal stages would ultimately result in medium-sized seeds having the highest dispersal success rates. In this study, by tracking a large number of seeds for 5 yr, we investigated the effects of seed size on seed fates from seed removal to seedling establishment of a dominant plant Pittosporopsis kerrii (Icacinaceae) dispersed by scatter-hoarding rodents in tropical forest in southwest China. We found that small seeds had a lower survival rate at the early dispersal stage where more small seeds were predated at seed stations and after removal; large seeds had a lower survival rate at the late dispersal stage, more large seeds were recovered, predated after being cached, or larder-hoarded. Medium-sized seeds experienced the highest dispersal success. Our study suggests that differential foraging preferences by scatter-hoarding rodents at different stages of seed dispersal could result in conflicting selective pressures on seed size and higher dispersal success of medium-sized seeds. © 2016 by the Ecological Society of America.

Pollution control and metal resource recovery for low grade automobile shredder residue: a mechanism, bioavailability and risk assessment.

PubMed

Singh, Jiwan; Lee, Byeong-Kyu

2015-04-01

Automobile shredder residue (ASR) is considered as hazardous waste in Japan and European countries due to presence of heavy metals. This study was carried on the extraction characteristics of heavy metals (Mn, Fe, Ni, and Cr) from automobile shredder residue (ASR). The effects of pH, temperature, particle size, and liquid/solid ratio (L/S) on the extraction of heavy metals were investigated. The recovery rate of Mn, Fe, Ni, and Cr increased with increasing extraction temperature and L/S ratio. The lowest pH 2, the highest L/S ratio, and the smallest particle size showed the highest recovery of heavy metals from ASR. The highest recovery rates were in the following order: Mn > Ni > Cr > Fe. Reduction of mobility factor for the heavy metals was observed in all the size fractions after the recovery. The results of the kinetic analysis for various experimental conditions supported that the reaction rate of the recovery process followed a second order reaction model (R(2) ⩾ 0.95). The high availability of water-soluble fractions of Mn, Fe, Ni, and Cr from the low grade ASR could be potential hazards to the environment. Bioavailability and toxicity risk of heavy metals reduced significantly with pH 2 of distilled water. However, water is a cost-effective extracting agent for the recovery of heavy metals and it could be useful for reducing the toxicity of ASR. Copyright © 2015 Elsevier Ltd. All rights reserved.

Cognitive effects of two nutraceuticals Ginseng and Bacopa benchmarked against modafinil: a review and comparison of effect sizes

PubMed Central

Neale, Chris; Camfield, David; Reay, Jonathon; Stough, Con; Scholey, Andrew

2013-01-01

Over recent years there has been increasing research into both pharmaceutical and nutraceutical cognition enhancers. Here we aimed to calculate the effect sizes of positive cognitive effect of the pharmaceutical modafinil in order to benchmark the effect of two widely used nutraceuticals Ginseng and Bacopa (which have consistent acute and chronic cognitive effects, respectively). A search strategy was implemented to capture clinical studies into the neurocognitive effects of modafinil, Ginseng and Bacopa. Studies undertaken on healthy human subjects using a double‐blind, placebo‐controlled design were included. For each study where appropriate data were included, effect sizes (Cohen's d) were calculated for measures showing significant positive and negative effects of treatment over placebo. The highest effect sizes for cognitive outcomes were 0.77 for modafinil (visuospatial memory accuracy), 0.86 for Ginseng (simple reaction time) and 0.95 for Bacopa (delayed word recall). These data confirm that neurocognitive enhancement from well characterized nutraceuticals can produce cognition enhancing effects of similar magnitude to those from pharmaceutical interventions. Future research should compare these effects directly in clinical trials. PMID:23043278

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

Pokharel, S; Rana, S

Purpose: purpose of this study is to evaluate the effect of grid size in Eclipse AcurosXB dose calculation algorithm for SBRT lung. Methods: Five cases of SBRT lung previously treated have been chosen for present study. Four of the plans were 5 fields conventional IMRT and one was Rapid Arc plan. All five cases have been calculated with five grid sizes (1, 1.5, 2, 2.5 and 3mm) available for AXB algorithm with same plan normalization. Dosimetric indices relevant to SBRT along with MUs and time have been recorded for different grid sizes. The maximum difference was calculated as a percentagemore » of mean of all five values. All the plans were IMRT QAed with portal dosimetry. Results: The maximum difference of MUs was within 2%. The time increased was as high as 7 times from highest 3mm to lowest 1mm grid size. The largest difference of PTV minimum, maximum and mean dose were 7.7%, 1.5% and 1.6% respectively. The highest D2-Max difference was 6.1%. The highest difference in ipsilateral lung mean, V5Gy, V10Gy and V20Gy were 2.6%, 2.4%, 1.9% and 3.8% respectively. The maximum difference of heart, cord and esophagus dose were 6.5%, 7.8% and 4.02% respectively. The IMRT Gamma passing rate at 2%/2mm remains within 1.5% with at least 98% points passing with all grid sizes. Conclusion: This work indicates the lowest grid size of 1mm available in AXB is not necessarily required for accurate dose calculation. The IMRT passing rate was insignificant or not observed with the reduction of grid size less than 2mm. Although the maximum percentage difference of some of the dosimetric indices appear large, most of them are clinically insignificant in absolute dose values. So we conclude that 2mm grid size calculation is best compromise in light of dose calculation accuracy and time it takes to calculate dose.« less

Anaerobic co-digestion of food waste and dairy manure: effects of food waste particle size and organic loading rate.

PubMed

Agyeman, Fred O; Tao, Wendong

2014-01-15

This study was to comprehensively evaluate the effects of food waste particle size on co-digestion of food waste and dairy manure at organic loading rates increased stepwise from 0.67 to 3 g/L/d of volatile solids (VS). Three anaerobic digesters were fed semi-continuously with equal VS amounts of food waste and dairy manure. Food waste was ground to 2.5 mm (fine), 4 mm (medium), and 8 mm (coarse) for the three digesters, respectively. Methane production rate and specific methane yield were significantly higher in the digester with fine food waste. Digestate dewaterability was improved significantly by reducing food waste particle size. Specific methane yield was highest at the organic loading rate of 2g VS/L/d, being 0.63, 0.56, and 0.47 L CH4/g VS with fine, medium, and coarse food waste, respectively. Methane production rate was highest (1.40-1.53 L CH4/L/d) at the organic loading rate of 3 g VS/L/d. The energy used to grind food waste was minor compared with the heating value of the methane produced. Copyright © 2013 Elsevier Ltd. All rights reserved.

The Effects of Equipment Modification on Children's Self-Efficacy and Basketball Shooting Performance.

ERIC Educational Resources Information Center

Chase, Melissa A.; And Others

1994-01-01

Reports a study that examined the effects of modification of basketball size and basket height on shooting performance and self-efficacy of children ages 9-12 years. Subjects completed a self-efficacy questionnaire before and after shooting 10 baskets under 4 conditions. Self-efficacy was highest when children shot at a lower basket. (SM)

The influence of mass configurations on velocity amplified vibrational energy harvesters

NASA Astrophysics Data System (ADS)

O'Donoghue, D.; Frizzell, R.; Kelly, G.; Nolan, K.; Punch, J.

2016-05-01

Vibrational energy harvesters scavenge ambient vibrational energy, offering an alternative to batteries for the autonomous operation of low power electronics. Velocity amplified electromagnetic generators (VAEGs) utilize the velocity amplification effect to increase power output and operational bandwidth, compared to linear resonators. A detailed experimental analysis of the influence of mass ratio and number of degrees-of-freedom (dofs) on the dynamic behaviour and power output of a macro-scale VAEG is presented. Various mass configurations are tested under drop-test and sinusoidal forced excitation, and the system performances are compared. For the drop-test, increasing mass ratio and number of dofs increases velocity amplification. Under forced excitation, the impacts between the masses are more complex, inducing greater energy losses. This results in the 2-dof systems achieving the highest velocities and, hence, highest output voltages. With fixed transducer size, higher mass ratios achieve higher voltage output due to the superior velocity amplification. Changing the magnet size to a fixed percentage of the final mass showed the increase in velocity of the systems with higher mass ratios is not significant enough to overcome the reduction in transducer size. Consequently, the 3:1 mass ratio systems achieved the highest output voltage. These findings are significant for the design of future reduced-scale VAEGs.

Extraction of citral oil from lemongrass (Cymbopogon Citratus) by steam-water distillation technique

NASA Astrophysics Data System (ADS)

Alam, P. N.; Husin, H.; Asnawi, T. M.; Adisalamun

2018-04-01

In Indonesia, production of citral oil from lemon grass (Cymbopogon Cytratus) is done by a traditional technique whereby a low yield results. To improve the yield, an appropriate extraction technology is required. In this research, a steam-water distillation technique was applied to extract the essential oil from the lemongrass. The effects of sample particle size and bed volume on yield and quality of citral oil produced were investigated. The drying and refining time of 2 hours were used as fixed variables. This research results that minimum citral oil yield of 0.53% was obtained on sample particle size of 3 cm and bed volume of 80%, whereas the maximum yield of 1.95% on sample particle size of 15 cm and bed volume of 40%. The lowest specific gravity of 0.80 and the highest specific gravity of 0.905 were obtained on sample particle size of 8 cm with bed volume of 80% and particle size of 12 cm with bed volume of 70%, respectively. The lowest refractive index of 1.480 and the highest refractive index of 1.495 were obtained on sample particle size of 8 cm with bed volume of 70% and sample particle size of 15 cm with bed volume of 40%, respectively. The solubility of the produced citral oil in alcohol was 70% in ratio of 1:1, and the citral oil concentration obtained was around 79%.

The impact of particle size and initial solid loading on thermochemical pretreatment of wheat straw for improving sugar recovery.

PubMed

Rojas-Rejón, Oscar A; Sánchez, Arturo

2014-07-01

This work studies the effect of initial solid load (4-32 %; w/v, DS) and particle size (0.41-50 mm) on monosaccharide yield of wheat straw subjected to dilute H(2)SO(4) (0.75 %, v/v) pretreatment and enzymatic saccharification. Response surface methodology (RSM) based on a full factorial design (FFD) was used for the statistical analysis of pretreatment and enzymatic hydrolysis. The highest xylose yield obtained during pretreatment (ca. 86 %; of theoretical) was achieved at 4 % (w/v, DS) and 25 mm. The solid fraction obtained from the first set of experiments was subjected to enzymatic hydrolysis at constant enzyme dosage (17 FPU/g); statistical analysis revealed that glucose yield was favored with solids pretreated at low initial solid loads and small particle sizes. Dynamic experiments showed that glucose yield did not increase after 48 h of enzymatic hydrolysis. Once established pretreatment conditions, experiments were carried out with several initial solid loading (4-24 %; w/v, DS) and enzyme dosages (5-50 FPU/g). Two straw sizes (0.41 and 50 mm) were used for verification purposes. The highest glucose yield (ca. 55 %; of theoretical) was achieved at 4 % (w/v, DS), 0.41 mm and 50 FPU/g. Statistical analysis of experiments showed that at low enzyme dosage, particle size had a remarkable effect over glucose yield and initial solid load was the main factor for glucose yield.

Physical and thermal processing of Waste Printed Circuit Boards aiming for the recovery of gold and copper.

PubMed

Ventura, E; Futuro, A; Pinho, S C; Almeida, M F; Dias, J M

2018-06-20

The recovery of electronic waste to obtain secondary raw materials is a subject of high relevance in the context of circular economy. Accordingly, the present work relies on the evaluation of mining separation/concentration techniques (comminution, size screening, magnetic separation and gravity concentration) alone as well as combined with thermal pre-treatment to recover gold and copper from Waste Printed Circuit Boards. For that purpose, Waste Printed Circuit Boards were subjected to physical processing (comminution, size screening in 6 classes from <0.425 mm to > 6.70 mm, magnetic separation and gravity concentration) alone and combined with thermal treatment (200-500 °C), aiming the recovery of gold and copper. Mixed motherboards and graphic cards (Lot 1 and 3) and highly rich components (connectors separated from memory cards, Lot 2) were analyzed. Gold and copper concentrations were determined before and after treatment. Before treatment, concentrations from 0.01 to 0.6 % wt. and from 9 to 20 % wt. were found for gold and copper respectively. The highest concentrations were observed in the size fractions between 0.425 and 1.70 mm. The highest copper concentration was around 35 % wt. (class 0.425-0.85 mm) and when analyzing memory card connectors alone, gold concentrations reached almost 2% in the same class, reflecting the interest of separating such components. The physical treatment alone was more effective for Lot 1/3, compared to Lot 2, allowing recoveries of 67 % wt. and 87 % wt. for gold and copper respectively, mostly due to differences in particles size and shape. The thermal treatment showed unperceptive influence on gold concentration but significant effect for copper concentration, mostly attributed to the size of the copper particles. Concentrations increased in a factor of around 10 when the thermal treatment was performed at 300 °C for the larger particles (1.70-6.70 mm); the best results were obtained at 400 °C for the other sizes, when the highest rate of thermal decomposition of the material occurred. Copyright © 2018 Elsevier Ltd. All rights reserved.

Effects of processing, particle size and moisturizing of sorghum-based feeds on pellet quality and broiler production.

PubMed

da Silva, Patrícia Garcia; Oliveira, Luana Martins Schaly; de Oliveira, Nayanne Rodrigues; de Moura Júnior, Fábio Ataides; Silva, Maura Regina Sousa; Cordeiro, Deibity Alves; Minafra, Cibele Silva; Dos Santos, Fabiana Ramos

2018-01-01

This study aimed to assess the effect of pelleted and expanded sorghum-based feeds prepared with different moisture levels and particle size of ingredients on metabolizable energy, ileal digestibility of amino acids and broiler performance. The experiment was performed with 720 male broiler chicks of the Cobb strain, with treatments of six replications, with 15 birds each; they were arranged in a completely randomized design and 2×2×2 factorial scheme (pelleted or expanded feed processing, 0.8% or 1.6% moisture addition in the mixer, and particle size of 650 or 850 microns). Higher pellet quality (pellets, % and pellet durability index [PDI]) was obtained in expanded diets and inclusion of 1.6% moisture. The particle size of 850 microns increased the PDI of final diet. All studied treatments had no significant effect on weight gain and broiler carcass and cut yields. Lower feed conversion occurred for birds fed pelleted feed at 42 d. The highest apparent metabolizable energy (AME) and apparent metabolizable energy corrected to zero nitrogen balance (AMEn) values of feed in the initial rearing phase (10 to 13 days) were observed in birds fed pelleted feed or for feed prepared with 1.6% moisture. The highest ileal digestibility coefficients of amino acids were obtained with the consumption of pelleted feed prepared with a particle size of 650 microns and 1.6% moisture. Pelleted feed prepared with a milling particle size of 650 microns and 1.6% moisture provided increased ileal digestibility of amino acids and AMEn in the starter period. However, the expanded feed improved pellet quality and feed conversion of broilers at 42 days of age. We conclude that factors such as moisture, particle size and processing affect the pellet quality, and therefore should be considered when attempting to optimize broiler performance.

Effects of processing, particle size and moisturizing of sorghum-based feeds on pellet quality and broiler production

PubMed Central

2018-01-01

Objective This study aimed to assess the effect of pelleted and expanded sorghum-based feeds prepared with different moisture levels and particle size of ingredients on metabolizable energy, ileal digestibility of amino acids and broiler performance. Methods The experiment was performed with 720 male broiler chicks of the Cobb strain, with treatments of six replications, with 15 birds each; they were arranged in a completely randomized design and 2×2×2 factorial scheme (pelleted or expanded feed processing, 0.8% or 1.6% moisture addition in the mixer, and particle size of 650 or 850 microns). Results Higher pellet quality (pellets, % and pellet durability index [PDI]) was obtained in expanded diets and inclusion of 1.6% moisture. The particle size of 850 microns increased the PDI of final diet. All studied treatments had no significant effect on weight gain and broiler carcass and cut yields. Lower feed conversion occurred for birds fed pelleted feed at 42 d. The highest apparent metabolizable energy (AME) and apparent metabolizable energy corrected to zero nitrogen balance (AMEn) values of feed in the initial rearing phase (10 to 13 days) were observed in birds fed pelleted feed or for feed prepared with 1.6% moisture. The highest ileal digestibility coefficients of amino acids were obtained with the consumption of pelleted feed prepared with a particle size of 650 microns and 1.6% moisture. Conclusion Pelleted feed prepared with a milling particle size of 650 microns and 1.6% moisture provided increased ileal digestibility of amino acids and AMEn in the starter period. However, the expanded feed improved pellet quality and feed conversion of broilers at 42 days of age. We conclude that factors such as moisture, particle size and processing affect the pellet quality, and therefore should be considered when attempting to optimize broiler performance. PMID:28920405

Effect of Cutting Velocity / Stem Size on the Efficiency of NRCRI Cassave Stem Cutting Machine

NASA Astrophysics Data System (ADS)

Ikejiofor, M. C.

2012-11-01

The developed NRCRI (National Root Crops Research Institute) cassava stem cutting machine was evaluated. The cassava stems from the variety TME 419 were used. The sizes of the stem used were 1.8, 2.0, 2.3 and 2.6cm. Also, different cutting velocities of 1.20, 1.23 and 1.32m/s were used. The stakes produced has length of 2.5cm. Analysis of variance in RCBD was used to evaluate the effect of the cutting velocity and the stem size on the efficiency of the cutting machine. The result of the analysis showed that the cutting velocity had very highly significant effect, while the stem size had no significant effect at 5% level on the efficiency of the cutting machine. The data obtained also showed that the highest and least cutting efficiencies of 99.42 and 94.71% were obtained with the machine cutting velocities of 1.2 and 1.32m/s respectively.

Effects of size and temperature on metabolic rate.

PubMed

Gillooly, J F; Brown, J H; West, G B; Savage, V M; Charnov, E L

2001-09-21

We derive a general model, based on principles of biochemical kinetics and allometry, that characterizes the effects of temperature and body mass on metabolic rate. The model fits metabolic rates of microbes, ectotherms, endotherms (including those in hibernation), and plants in temperatures ranging from 0 degrees to 40 degrees C. Mass- and temperature-compensated resting metabolic rates of all organisms are similar: The lowest (for unicellular organisms and plants) is separated from the highest (for endothermic vertebrates) by a factor of about 20. Temperature and body size are primary determinants of biological time and ecological roles.

Effect of Cobalt Particle Size on Acetone Steam Reforming

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

Sun, Junming; Zhang, He; Yu, Ning

2015-06-11

Carbon-supported cobalt nanoparticles with different particle sizes were synthesized and characterized by complementary characterization techniques such as X-ray diffraction, N-2 sorption, acetone temperature-programmed desorption, transmission electron microscopy, and CO chemisorption. Using acetone steam reforming reaction as a probe reaction, we revealed a volcano-shape curve of the intrinsic activity (turnover frequency of acetone) and the CO2 selectivity as a function of the cobalt particle size with the highest activity and selectivity observed at a particle size of approximately 12.8nm. Our results indicate that the overall performance of acetone steam reforming is related to a combination of particle-size-dependent acetone decomposition, water dissociation,more » and the oxidation state of the cobalt nanoparticles.« less

Size-Controlled Synthesis of Sub-10 nm PtNi3 Alloy Nanoparticles and their Unusual Volcano-Shaped Size Effect on ORR Electrocatalysis.

PubMed

Gan, Lin; Rudi, Stefan; Cui, Chunhua; Heggen, Marc; Strasser, Peter

2016-06-01

Dealloyed Pt bimetallic core-shell catalysts derived from low-Pt bimetallic alloy nanoparticles (e.g, PtNi3 ) have recently shown unprecedented activity and stability on the cathodic oxygen reduction reaction (ORR) under realistic fuel cell conditions and become today's catalyst of choice for commercialization of automobile fuel cells. A critical step toward this breakthrough is to control their particle size below a critical value (≈10 nm) to suppress nanoporosity formation and hence reduce significant base metal (e.g., Ni) leaching under the corrosive ORR condition. Fine size control of the sub-10 nm PtNi3 nanoparticles and understanding their size dependent ORR electrocatalysis are crucial to further improve their ORR activity and stability yet still remain unexplored. A robust synthetic approach is presented here for size-controlled PtNi3 nanoparticles between 3 and 10 nm while keeping a constant particle composition and their size-selected growth mechanism is studied comprehensively. This enables us to address their size-dependent ORR activities and stabilities for the first time. Contrary to the previously established monotonic increase of ORR specific activity and stability with increasing particle size on Pt and Pt-rich bimetallic nanoparticles, the Pt-poor PtNi3 nanoparticles exhibit an unusual "volcano-shaped" size dependence, showing the highest ORR activity and stability at the particle sizes between 6 and 8 nm due to their highest Ni retention during long-term catalyst aging. The results of this study provide important practical guidelines for the size selection of the low Pt bimetallic ORR electrocatalysts with further improved durably high activity. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Cognitive effects of two nutraceuticals Ginseng and Bacopa benchmarked against modafinil: a review and comparison of effect sizes.

PubMed

Neale, Chris; Camfield, David; Reay, Jonathon; Stough, Con; Scholey, Andrew

2013-03-01

Over recent years there has been increasing research into both pharmaceutical and nutraceutical cognition enhancers. Here we aimed to calculate the effect sizes of positive cognitive effect of the pharmaceutical modafinil in order to benchmark the effect of two widely used nutraceuticals Ginseng and Bacopa (which have consistent acute and chronic cognitive effects, respectively). A search strategy was implemented to capture clinical studies into the neurocognitive effects of modafinil, Ginseng and Bacopa. Studies undertaken on healthy human subjects using a double-blind, placebo-controlled design were included. For each study where appropriate data were included, effect sizes (Cohen's d) were calculated for measures showing significant positive and negative effects of treatment over placebo. The highest effect sizes for cognitive outcomes were 0.77 for modafinil (visuospatial memory accuracy), 0.86 for Ginseng (simple reaction time) and 0.95 for Bacopa (delayed word recall). These data confirm that neurocognitive enhancement from well characterized nutraceuticals can produce cognition enhancing effects of similar magnitude to those from pharmaceutical interventions. Future research should compare these effects directly in clinical trials. © 2012 The Authors. British Journal of Clinical Pharmacology © 2012 The British Pharmacological Society.

Lambmeat colour values (HunterLab CIE and reflectance) are influenced by aperture size (5 mm v. 25 mm).

PubMed

Holman, Benjamin W B; Ponnampalam, Eric N; van de Ven, Remy J; Kerr, Matthew G; Hopkins, David L

2015-02-01

The effect of aperture size on the assessment of lamb meat colour values (L*, a*, b* and R630/580)was investigated. Two experiments using 2 HunterLab MiniScan colorimeters (large [25 mm] and small [5 mm] apertures) were conducted: 1) coloured tiles were measured and 2) unaged lamb (n = 65) m. longissimus lumborum (LL) and m. semimembranosus (SM) muscles were measured over 2.5 d under simulated retail display. For Experiment three, 2 different colorimeters were used on lamb (n = 36) LL aged for 6 weeks before measurement over 4 don simulated retail display. Coloured tile a* and b* values were unaffected by aperture size, but L* values and the R630/580 ratio were influenced by aperture size. The effect of aperture size on lamb meat colour measurements varied with display time and muscle type. The large aperture size generally provided the highest colorimetric values, and is recommended for measuring lamb meat colour.

Rain, prey and predators: climatically driven shifts in frog abundance modify reproductive allometry in a tropical snake.

PubMed

Brown, Gregory P; Shine, Richard

2007-11-01

To predict the impacts of climate change on animal populations, we need long-term data sets on the effects of annual climatic variation on the demographic traits (growth, survival, reproductive output) that determine population viability. One frequent complication is that fecundity also depends upon maternal body size, a trait that often spans a wide range within a single population. During an eight-year field study, we measured annual variation in weather conditions, frog abundance and snake reproduction on a floodplain in the Australian wet-dry tropics. Frog numbers varied considerably from year to year, and were highest in years with hotter wetter conditions during the monsoonal season ("wet season"). Mean maternal body sizes, egg sizes and post-partum maternal body conditions of frog-eating snakes (keelback, Tropidonophis mairii, Colubridae) showed no significant annual variation over this period, but mean clutch sizes were higher in years with higher prey abundance. Larger females were more sensitive to frog abundance in this respect than were smaller conspecifics, so that the rate at which fecundity increased with body size varied among years, and was highest when prey availability was greatest. Thus, the link between female body size and reproductive output varied among years, with climatic factors modifying the relative reproductive rates of larger (older) versus smaller (younger) animals within the keelback population.

The Exposure Effects of Online Model Pictures and Weight-Related Persuasive Messages on Women's Weight-Loss Planned Behaviors.

PubMed

Pan, Wenjing; Peña, Jorge

2017-10-01

This study examined how exposure to pictures of women with different body sizes (thin, obese), physical attractiveness levels (attractive, unattractive), along with exposure to weight-related messages (pro-anorexia, anti-anorexia) embedded in a fashion website affected female participants' planned behavior toward weight loss. Participants exposed to attractive model pictures showed higher intentions, attitudes, and subjective norms to lose weight compared with unattractive models. Additionally, participants exposed to thin and attractive model pictures indicated the highest attitudes and self-efficacy to lose weight, whereas those exposed to thin and unattractive model pictures indicated the lowest. Furthermore, weight-related messages moderated the effect of model appearance (body size and attractiveness) on controllability of weight-loss activities. However, website pictures' body size differences had no main effects on planned behavior toward weight loss. These effects are discussed in the light of social comparison mechanisms.

The Effect of Calcium Phosphate Particle Shape and Size on their Antibacterial and Osteogenic Activity in the Delivery of Antibiotics in vitro

PubMed Central

Uskoković, Vuk; Batarni, Samir Shariff; Schweicher, Julien; King, Andrew; Desai, Tejal A.

2013-01-01

Powders composed of four morphologically different calcium phosphate particles were prepared by precipitation from aqueous solutions: flaky, brick-like, elongated orthogonal, and spherical. The particles were then loaded with either clindamycin phosphate as the antibiotic of choice, or fluorescein, a model molecule used to assess the drug release properties. A comparison was carried out of the comparative effect of such antibiotic-releasing materials on: sustained drug release profiles; Staphylococcus aureus growth inhibition; and osteogenic propensities in vitro. Raman spectroscopic analysis indicated the presence of various calcium phosphate phases, including monetite (flaky and elongated orthogonal particles), octacalcium phosphate (brick-shaped particles) and hydroxyapatite (spherical particles). Testing the antibiotic-loaded calcium phosphate powders for bacterial growth inhibition demonstrated satisfying antibacterial properties both in broths and on agar plates. All four calcium-phosphate-fluorescein powders exhibited sustained drug release over 21 days. The calcium phosphate sample with the highest specific surface area and the smallest, spherical particle size was the most effective in both drug loading and release, consequently having the highest antibacterial efficiency. Moreover, the highest cell viability, the largest gene expression upregulation of three different osteogenic markers – osteocalcin, osteopontin and Runx2 - as well as the least disrupted cell cytoskeleton and cell morphologies were also noticed for the calcium phosphate powder composed of smallest, spherical nanosized particles. Still, all four powders exerted a viable effect on osteoblastic MC3T3-E1 cells in vitro, as evidenced by both morphological assessments on fluorescently stained cells and measurements of their mitochondrial activity. The obtained results suggest that the nanoscale particle size and the corresponding coarseness of the surface of particle conglomerates as the cell attachment points may present a favorable starting point for the development of calcium-phosphate-based osteogenic drug delivery devices. PMID:23484624

Communication Technologies Preferred by School Based Administrators

ERIC Educational Resources Information Center

Weir, Paul

2012-01-01

The purpose of this study was to determine the communication technologies preferred by school based administrators. This study surveyed and interviewed 96 school based administrators in a mid-sized suburban school system. The data show that individual emails, email lists, and cell phone technologies had the highest percentage effectiveness ratings…

Evidence for the role of hindbrain orexin-1 receptors in the control of meal size

PubMed Central

Parise, Eric M.; Lilly, Nicole; Kay, Kristen; Dossat, Amanda M.; Seth, Rohit; Overton, J. Michael

2011-01-01

Hypothalamic orexin neurons project to the hindbrain, and 4th-ventricle intracerebroventricular (4th-icv) injection of orexin-A treatment increases food intake. We assessed the effects of hindbrain orexin-A and the orexin-1-receptor antagonist SB334867 on meal pattern in rats consuming standard chow. When injected 4th-icv shortly before dark onset, lower doses of orexin-A increased food intake over a 2-h period by increasing the size of the first meal relative to vehicle, whereas the highest dose increased food intake by causing the second meal to be taken sooner. Conversely, hindbrain SB334867 reduced food intake by decreasing the size of the first meal of the dark phase. We also examined the effects of 4th-icv orexin-A and SB334867 on locomotor activity. Only the highest dose of orexin-A increased activity, and SB334867 had no effect. In addition, hindbrain SB334867 induced c-Fos in the nucleus of the solitary tract. These data support the suggestion that endogenous hindbrain orexin-A acts to limit satiation. Both orexin-A and the pancreatic satiation hormone amylin require an intact area postrema to affect food intake, so we asked whether 4th-icv orexin-A impairs the satiating effect of peripheral amylin treatment. Amylin reduced the size of the first meal of the dark cycle when rats were pretreated with 4th-icv saline, yet amylin was ineffective after 4th-icv orexin-A pretreatment. Using double-label immunohistochemistry, we determined that some orexin-A fibers in the area postrema are located in proximity to amylin-responsive neurons. Therefore, hindbrain orexin-A may increase food intake, in part, by reducing the ability of rats to respond to amylin during a meal. PMID:21957165

Landscape heterogeneity-biodiversity relationship: effect of range size.

PubMed

Katayama, Naoki; Amano, Tatsuya; Naoe, Shoji; Yamakita, Takehisa; Komatsu, Isamu; Takagawa, Shin-ichi; Sato, Naoto; Ueta, Mutsuyuki; Miyashita, Tadashi

2014-01-01

The importance of landscape heterogeneity to biodiversity may depend on the size of the geographic range of species, which in turn can reflect species traits (such as habitat generalization) and the effects of historical and contemporary land covers. We used nationwide bird survey data from Japan, where heterogeneous landscapes predominate, to test the hypothesis that wide-ranging species are positively associated with landscape heterogeneity in terms of species richness and abundance, whereas narrow-ranging species are positively associated with landscape homogeneity in the form of either open or forest habitats. We used simultaneous autoregressive models to explore the effects of climate, evapotranspiration, and landscape heterogeneity on the richness and abundance of breeding land-bird species. The richness of wide-ranging species and the total species richness were highest in heterogeneous landscapes, where many wide-ranging species showed the highest abundance. In contrast, the richness of narrow-ranging species was not highest in heterogeneous landscapes; most of those species were abundant in either open or forest landscapes. Moreover, in open landscapes, narrow-ranging species increased their species richness with decreasing temperature. These results indicate that heterogeneous landscapes are associated with rich bird diversity but that most narrow-ranging species prefer homogeneous landscapes--particularly open habitats in colder regions, where grasslands have historically predominated. There is a need to reassess the generality of the heterogeneity-biodiversity relationship, with attention to the characteristics of species assemblages determined by environments at large spatiotemporal scales.

Landscape Heterogeneity–Biodiversity Relationship: Effect of Range Size

PubMed Central

Katayama, Naoki; Amano, Tatsuya; Naoe, Shoji; Yamakita, Takehisa; Komatsu, Isamu; Takagawa, Shin-ichi; Sato, Naoto; Ueta, Mutsuyuki; Miyashita, Tadashi

2014-01-01

The importance of landscape heterogeneity to biodiversity may depend on the size of the geographic range of species, which in turn can reflect species traits (such as habitat generalization) and the effects of historical and contemporary land covers. We used nationwide bird survey data from Japan, where heterogeneous landscapes predominate, to test the hypothesis that wide-ranging species are positively associated with landscape heterogeneity in terms of species richness and abundance, whereas narrow-ranging species are positively associated with landscape homogeneity in the form of either open or forest habitats. We used simultaneous autoregressive models to explore the effects of climate, evapotranspiration, and landscape heterogeneity on the richness and abundance of breeding land-bird species. The richness of wide-ranging species and the total species richness were highest in heterogeneous landscapes, where many wide-ranging species showed the highest abundance. In contrast, the richness of narrow-ranging species was not highest in heterogeneous landscapes; most of those species were abundant in either open or forest landscapes. Moreover, in open landscapes, narrow-ranging species increased their species richness with decreasing temperature. These results indicate that heterogeneous landscapes are associated with rich bird diversity but that most narrow-ranging species prefer homogeneous landscapes—particularly open habitats in colder regions, where grasslands have historically predominated. There is a need to reassess the generality of the heterogeneity-biodiversity relationship, with attention to the characteristics of species assemblages determined by environments at large spatiotemporal scales. PMID:24675969

Effect of Particle and Carbide Grain Sizes on a HVOAF WC-Co-Cr Coating for the Future Application on Internal Surfaces: Microstructure and Wear

NASA Astrophysics Data System (ADS)

Pulsford, J.; Kamnis, S.; Murray, J.; Bai, M.; Hussain, T.

2018-01-01

The use of nanoscale WC grain or finer feedstock particles is a possible method of improving the performance of WC-Co-Cr coatings. Finer powders are being pursued for the development of coating internal surfaces, as less thermal energy is required to melt the finer powder compared to coarse powders, permitting spraying at smaller standoff distances. Three WC-10Co-4Cr coatings, with two different powder particle sizes and two different carbide grain sizes, were sprayed using a high velocity oxy-air fuel (HVOAF) thermal spray system developed by Castolin Eutectic-Monitor Coatings Ltd., UK. Powder and coating microstructures were characterized using XRD and SEM. Fracture toughness and dry sliding wear performance at three loads were investigated using a ball-on-disk tribometer with a WC-Co counterbody. It was found that the finer powder produced the coating with the highest microhardness, but its fracture toughness was reduced due to increased decarburization compared to the other powders. The sprayed nanostructured powder had the lowest microhardness and fracture toughness of all materials tested. Unlubricated sliding wear testing at the lowest load showed the nanostructured coating performed best; however, at the highest load this coating showed the highest specific wear rates with the other two powders performing to a similar, better standard.

Characterization of indigenous chicken production systems in Kenya.

PubMed

Okeno, Tobias O; Kahi, Alexander K; Peters, Kurt J

2012-03-01

Indigenous chicken (IC) and their production systems were characterized to understand how the whole system operates for purposes of identifying threats and opportunities for holistic improvement. A survey involving 594 households was conducted in six counties with the highest population of IC in Kenya using structured questionnaires. Data on IC farmers' management practices were collected and analysed and inbreeding levels calculated based on the effective population size. Indigenous chicken were ranked highest as a source of livestock income by households in medium- to high-potential agricultural areas, but trailed goats in arid and semi-arid areas. The production system practised was mainly low-input and small-scale free range, with mean flock size of 22.40 chickens per household. The mean effective population size was 16.02, translating to high levels of inbreeding (3.12%). Provision for food and cash income were the main reasons for raising IC, whilst high mortality due to diseases, poor nutrition, housing and marketing channels were the major constraints faced by farmers. Management strategies targeting improved healthcare, nutrition and housing require urgent mitigation measures, whilst rural access road network needs to be developed for ease of market accessibility. Sustainable genetic improvement programmes that account for farmers' multiple objectives, market requirements and the production circumstances should be developed for a full realization of IC productivity.

The effects of delay duration on visual working memory for orientation.

PubMed

Shin, Hongsup; Zou, Qijia; Ma, Wei Ji

2017-12-01

We used a delayed-estimation paradigm to characterize the joint effects of set size (one, two, four, or six) and delay duration (1, 2, 3, or 6 s) on visual working memory for orientation. We conducted two experiments: one with delay durations blocked, another with delay durations interleaved. As dependent variables, we examined four model-free metrics of dispersion as well as precision estimates in four simple models. We tested for effects of delay time using analyses of variance, linear regressions, and nested model comparisons. We found significant effects of set size and delay duration on both model-free and model-based measures of dispersion. However, the effect of delay duration was much weaker than that of set size, dependent on the analysis method, and apparent in only a minority of subjects. The highest forgetting slope found in either experiment at any set size was a modest 1.14°/s. As secondary results, we found a low rate of nontarget reports, and significant estimation biases towards oblique orientations (but no dependence of their magnitude on either set size or delay duration). Relative stability of working memory even at higher set sizes is consistent with earlier results for motion direction and spatial frequency. We compare with a recent study that performed a very similar experiment.

Synthesis of nanocrystalline CeO{sub 2} particles by different emulsion methods

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

Supakanapitak, Sunisa; Boonamnuayvitaya, Virote; Jarudilokkul, Somnuk, E-mail: somnuk.jar@kmutt.ac.th

2012-05-15

Cerium oxide nanoparticles were synthesized using three different methods of emulsion: (1) reversed micelle (RM); (2) emulsion liquid membrane (ELM); and (3) colloidal emulsion aphrons (CEAs). Ammonium cerium nitrate and polyoxyethylene-4-lauryl ether (PE4LE) were used as cerium and surfactant sources in this study. The powder was calcined at 500 Degree-Sign C to obtain CeO{sub 2}. The effect of the preparation procedure on the particle size, surface area, and the morphology of the prepared powders were investigated. The obtained powders are highly crystalline, and nearly spherical in shape. The average particle size and the specific surface area of the powders frommore » the three methods were in the range of 4-10 nm and 5.32-145.73 m{sup 2}/g, respectively. The CeO{sub 2} powders synthesized by the CEAs are the smallest average particle size, and the highest surface area. Finally, the CeO{sub 2} prepared by the CEAs using different cerium sources and surfactant types were studied. It was found that the surface tensions of cerium solution and the type of surfactant affect the particle size of CeO{sub 2}. - Graphical Abstract: The emulsion droplet size distribution and the TEM images of CeO{sub 2} prepared by different methods: reversed micelle (RM), emulsion liquid membrane (ELM) and colloidal emulsion aphrons (CEAs). Highlights: Black-Right-Pointing-Pointer Nano-sized CeO{sub 2} was successfully prepared by three different emulsion methods. Black-Right-Pointing-Pointer The colloidal emulsion aphrons method producing CeO{sub 2} with the highest surface area. Black-Right-Pointing-Pointer The surface tensions of a cerium solution have slightly effect on the particle size. Black-Right-Pointing-Pointer The size control could be interpreted in terms of the adsorption of the surfactant.« less

Effect of Particle Size and Operating Conditions on Pt 3Co PEMFC Cathode Catalyst Durability

DOE PAGES

Gummalla, Mallika; Ball, Sarah; Condit, David; ...

2015-05-29

The initial performance and decay trends of polymer electrolyte membrane fuel cells (PEMFC) cathodes with Pt 3Co catalysts of three mean particle sizes (4.9 nm, 8.1 nm, and 14.8 nm) with identical Pt loadings are compared. Even though the cathode based on 4.9 nm catalyst exhibited the highest initial electrochemical surface area (ECA) and mass activity, the cathode based on 8.1 nm catalyst showed better initial performance at high currents. Owing to the low mass activity of the large particles, the initial performance of the 14.8 nm Pt3Co-based electrode was the lowest. The performance decay rate of the electrodes withmore » the smallest Pt 3Co particle size was the highest and that of the largest Pt 3Co particle size was lowest. Interestingly, with increasing number of decay cycles (0.6 to 1.0 V, 50 mV/s), the relative improvement in performance of the cathode based on 8.1 nm Pt 3Co over the 4.9 nm Pt 3Co increased, owing to better stability of the 8.1 nm catalyst. The electron microprobe analysis (EMPA) of the decayed membrane-electrode assembly (MEA) showed that the amount of Co in the membrane was lower for the larger particles, and the platinum loss into the membrane also decreased with increasing particle size. This suggests that the higher initial performance at high currents with 8.1 nm Pt 3Co could be due to lower contamination of the ionomer in the electrode. Furthermore, lower loss of Co from the catalyst with increased particle size could be one of the factors contributing to the stability of ECA and mass activity of electrodes with larger cathode catalyst particles. To delineate the impact of particle size and alloy effects, these results are compared with prior work from our research group on size effects of pure platinum catalysts. The impact of PEMFC operating conditions, including upper potential, relative humidity, and temperature on the alloy catalyst decay trends, along with the EMPA analysis of the decayed MEAs, are reported.« less

Landscape responses of bats to habitat fragmentation in Atlantic forest of paraguay

USGS Publications Warehouse

Gorresen, P.M.; Willig, M.R.

2004-01-01

Understanding effects of habitat loss and fragmentation on populations or communities is critical to effective conservation and restoration. This is particularly important for bats because they provide vital services to ecosystems via pollination and seed dispersal, especially in tropical and subtropical habitats. Based on more than 1,000 h of survey during a 15-month period, we quantified species abundances and community structure of phyllostomid bats at 14 sites in a 3,000-km2 region of eastern Paraguay. Abundance was highest for Artibeus lituratus in deforested landscapes and for Chrotopterus auritus in forested habitats. In contrast, Artibeus fimbriatus, Carollia perspicillata, Glossophaga soricina, Platyrrhinus lineatus, Pygoderma bilabiatum, and Sturnira lilium attained highest abundance in moderately fragmented forest landscapes. Forest cover, patch size, and patch density frequently were associated with abundance of species. At the community level, species richness was highest in partly deforested landscapes, whereas evenness was greatest in forested habitat. In general, the highest diversity of bats occurred in landscapes comprising moderately fragmented forest habitat. This underscores the importance of remnant habitat patches to conservation strategies.

Water holding capacities of fly ashes: Effect of size fractionation

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

Sarkar, A.; Rano, R.

2007-07-01

Water holding capacities of fly ashes from different thermal power plants in Eastern India have been compared. Moreover, the effect of size fractionation (sieving) on the water holding capacities has also been determined. The desorption rate of water held by the fly ash fractions at ambient temperature (25-30{sup o}C) has been investigated. The effect of mixing various size fractions of fly ash in increasing the water holding capacities of fly ash has been studied. It is observed that the fly ash obtained from a thermal power plant working on stoker-fired combustor has the highest water holding capacity, followed by themore » one that works on pulverized fuel combustor. Fly ash collected from super thermal power plant has the least water holding capacity (40.7%). The coarser size fractions of fly ashes in general have higher water holding capacities than the finer ones. An attempt has been made to correlate the results obtained, with the potential use in agriculture.« less

Bottles as models: predicting the effects of varying swimming speed and morphology on size selectivity and filtering efficiency in fishes.

PubMed

Paig-Tran, E W Misty; Bizzarro, Joseph J; Strother, James A; Summers, Adam P

2011-05-15

We created physical models based on the morphology of ram suspension-feeding fishes to better understand the roles morphology and swimming speed play in particle retention, size selectivity and filtration efficiency during feeding events. We varied the buccal length, flow speed and architecture of the gills slits, including the number, size, orientation and pore size/permeability, in our models. Models were placed in a recirculating flow tank with slightly negatively buoyant plankton-like particles (~20-2000 μm) collected at the simulated esophagus and gill rakers to locate the highest density of particle accumulation. Particles were captured through sieve filtration, direct interception and inertial impaction. Changing the number of gill slits resulted in a change in the filtration mechanism of particles from a bimodal filter, with very small (≤ 50 μm) and very large (>1000 μm) particles collected, to a filter that captured medium-sized particles (101-1000 μm). The number of particles collected on the gill rakers increased with flow speed and skewed the size distribution towards smaller particles (51-500 μm). Small pore sizes (105 and 200 μm mesh size) had the highest filtration efficiencies, presumably because sieve filtration played a significant role. We used our model to make predictions about the filtering capacity and efficiency of neonatal whale sharks. These results suggest that the filtration mechanics of suspension feeding are closely linked to an animal's swimming speed and the structural design of the buccal cavity and gill slits.

The influence of sintering conditions on microstructure and mechanical properties of titanium dioxide scaffolds for the treatment of bone tissue defects.

PubMed

Rumian, Łucja; Reczyńska, Katarzyna; Wrona, Małgorzata; Tiainen, Hanna; Haugen, Håvard J; Pamuła, Elżbieta

2015-01-01

In this study the attempts to improve mechanical properties of highly-porous titanium dioxide scaffolds produced by polymer sponge replication method were investigated. Particularly the effect of two-step sintering at different temperatures on microstructure and mechanical properties (compression test) of the scaffolds were analysed. To this end microcomputed tomography and scanning electron microscopy were used as analytical methods. Our experiments showed that the most appropriate conditions of manufacturing were when the scaffolds were heat-treated at 1500 °C for 1 h followed by sintering at 1200 °C for 20 h. Such scaffolds exhibited the highest compressive strength which was correlated with the highest linear density and the lowest size of grains. Moreover, grain size distribution was narrower with predominating fraction of fine grains 10-20 μm in size. Smaller grains and higher linear density sug- gested that in this case densification process prevailed over undesirable process of grain coarsening, which finally resulted in im- proved mechanical properties of the scaffolds.

Hierarchical TiO{sub 2} submicron-sized spheres for enhanced power conversion efficiency in dye-sensitized solar cells

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

Wang, Hao; State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000; Guo, Zhiguang, E-mail: zguo@licp.cas.cn

Hierarchical TiO{sub 2} submicron-sized sphere scattering layer, with relatively large surface area and effective light scattering, shows enhanced power conversion efficiency in dye-sensitized solar cells. - Highlights: • Hierarchical TiO{sub 2} submicron-sized spheres (TiO{sub 2} HSSs) with diameters of 400–600 nm were synthesized. • The HSSs composed of nanoparticles of ∼14 nm have a relatively large surface area of ∼35 m{sup 2}/g. • DSC exhibited the highest cell efficiency (6.23%) compared with ones with pure P25 (5.50%) or HSS (2.00%) photoanodes. - Abstract: Hierarchical TiO{sub 2} submicron-sized spheres (TiO{sub 2} HSSs) with diameters of 400–600 nm were synthesized by amore » facile one-step solvothermal method in ethanol solvent. The HSSs composed of nanoparticles of ∼14 nm have a relatively large surface area of ∼35 m{sup 2}/g. When applied as the scattering overlayer in dye-sensitized solar cells (DSCs), such TiO{sub 2} HSSs effectively improved light harvesting and led to the increase of photocurrent in DSCs. Furthermore, bilayer-structured photoanode also provided fast electron transportation and long electron lifetime as confirmed by electrochemical impedance spectra. As a result, DSC based on P25 nanoparticle underlayer and HSS-2 overlayer exhibited the highest cell efficiency (6.23%) compared with ones with pure P25 (5.50%) or HSS-2 (2.00%) photoanodes.« less

Effect of the growth rate on the morphology and structural properties of hut-shaped Ge islands in Si(001).

PubMed

Yakimov, A I; Nikiforov, A I; Dvurechenskii, A V; Ulyanov, V V; Volodin, V A; Groetzschel, R

2006-09-28

The effect of Ge deposition rate on the morphology and structural properties of self-assembled Ge/Si(001) islands was studied. Ge/Si(001) layers were grown by solid-source molecular-beam epitaxy at 500 °C. We adjusted the Ge coverage, 6 monolayers (ML), and varied the Ge growth rate by a factor of 100, R = 0.02-2 ML s(-1), to produce films consisting of hut-shaped Ge islands. The samples were characterized by scanning tunnelling microscopy, Raman spectroscopy, and Rutherford backscattering measurements. The mean lateral size of Ge nanoclusters decreases from 14.1 nm at R = 0.02 ML s(-1) to 9.8 nm at R = 2 ML s(-1). The normalized width of the size distribution shows non-monotonic behaviour as a function of R and has a minimum value of 19% at R = 2 ML s(-1). Ge nanoclusters fabricated at the highest deposition rate demonstrate the best structural quality and the highest Ge content (∼0.9).

Effect of pH on particles size and gas sensing properties of In2O3 nanoparticles

NASA Astrophysics Data System (ADS)

Anand, Kanica; Thangaraj, Rengasamy; Singh, Ravi Chand

2016-05-01

In this work, indium oxide (In2O3) nanoparticles have been synthesized by co-precipitation method and the effect of pH on the structural and sensor response values of In2O3 nanoparticles has been reported. X-ray diffraction pattern (XRD) revealed the formation of cubic phase In2O3 nanoparticles. FESEM results indicate the formation of nearly spherical shape In2O3 nanoparticles. The band gap energy value changed with change in pH value and found to have highest value at pH 9. Indium oxide nanoparticles thus prepared were deposited as thick films on alumina substrates to act as gas sensors and their sensing response to ethanol vapors and LPG at 50 ppm was investigated at different operating temperatures. It has been observed that all sensors exhibited optimum response at 300°C towards ethanol and at 400°C towards LPG. In2O3 nanoparticles prepared at pH 9, being smallest in size as compared to other, exhibit highest sensor response (SR).

Joint Effects of Granule Size and Degree of Substitution on Octenylsuccinated Sweet Potato Starch Granules As Pickering Emulsion Stabilizers.

PubMed

Li, Jinfeng; Ye, Fayin; Lei, Lin; Zhou, Yun; Zhao, Guohua

2018-05-02

The granules of sweet potato starch were size fractionated into three portions with significantly different median diameters ( D 50 ) of 6.67 (small-sized), 11.54 (medium-sized), and 16.96 μm (large-sized), respectively. Each portion was hydrophobized at the mass-based degrees of substitution (DS m ) of approximately 0.0095 (low), 0.0160 (medium), and 0.0230 (high). The Pickering emulsion-stabilizing capacities of modified granules were tested, and the resultant emulsions were characterized. The joint effects of granule size and DS m on emulsifying capacity (EC) were investigated by response surface methodology. For small-, medium-, and large-sized fractions, their highest emulsifying capacities are comparable but, respectively, encountered at high (0.0225), medium (0.0158), and low (0.0095) DS m levels. The emulsion droplet size increased with granule size, and the number of freely scattered granules in emulsions decreased with DS m . In addition, the term of surface density of the octenyl succinic group (SD -OSG ) was first proposed for modified starch granules, and it was proved better than DS m in interpreting the emulsifying capacities of starch granules with varying sizes. The present results implied that, as the particulate stabilizers, the optimal DS m of modified starch granules is size specific.

A quantitative study of ramped radio frequency, magnetization transfer, and slab thickness in three-dimensional time-of-flight magnetic resonance angiography in a patient population.

PubMed

Goodrich, K C; Blatter, D D; Parker, D L; Du, Y P; Meyer, K J; Bernstein, M A

1996-06-01

The authors compare the effectiveness of various magnetic resonance (MR) angiography acquisition strategies in enhancing the visibility of small intracranial vessels. Blood vessel contrast-to-noise ratio (CNR) in time-of-flight MR angiography was studied as a function of vessel size and several selectable imaging parameters. Contrast-to-noise measurements were made on 257 vessel segments ranging in size from 0.3 mm to 4.2 mm in patients who recently had undergone intraarterial cerebral angiography. Imaging parameters studied included magnetization transfer, spatially variable radio frequency (RF) pulse profile (ramped RF), and imaging slab thickness. The combination of thin slabs (16 slices/slab), ramped RF, and magnetization transfer resulted in the highest CNR for all but the smallest vessel sizes. The smallest vessels (< 0.5 mm) had the highest CNR, using the thick slab (64 slices/slab) with ramped RF and magnetization transfer. Magnetization transfer always improved vessel CNR, but the improvement diminished as the slab thickness was reduced. The CNR increased with a decrease in slab thickness for all but the smallest vessel sizes. Overall, the results provide a quantitative demonstration that inflow enhancement of blood is reduced for small vessels. Thus, whereas magnetization transfer is important at all vessel sizes, it becomes the primary factor in improving the visibility of the smallest vessels.

An investigation into the characteristics and drug release properties of multiple W/O/W emulsion systems containing low concentration of lipophilic polymeric emulsifier.

PubMed

Vasiljevic, Dragana; Parojcic, Jelena; Primorac, Marija; Vuleta, Gordana

2006-02-17

Multiple W/O/W emulsions with high content of inner phase (Phi1=Phi2=0.8) were prepared using relatively low concentrations of lipophilic polymeric primary emulsifier, PEG 30-dipolyhydroxystearate, and diclofenac diethylamine (DDA) as a model drug. The investigated formulations were characterized and their stability over the time was evaluated by dynamic and oscillatory rheological measurements, microscopic analysis and in vitro drug release study. In vitro release profiles of the selected model drug were evaluated in terms of the effective diffusion coefficients and flux of the released drug. The multiple emulsion samples exhibited good stability during the ageing time. Concentration of the lipophilic primary emulsifier markedly affected rheological behaviour as well as the droplet size and in vitro drug release kinetics of the investigated systems. The multiple emulsion systems with highest concentration (2.4%, w/w) of the primary emulsifier had the lowest droplet size and the highest apparent viscosity and highest elastic characteristics. Drug release data indicated predominately diffusional drug release mechanism with sustained and prolonged drug release accomplished with 2.4% (w/w) of lipophilic emulsifier employed.

Surface-enhanced Raman spectroscopy on laser-engineered ruthenium dye-functionalized nanoporous gold

NASA Astrophysics Data System (ADS)

Schade, Lina; Franzka, Steffen; Biener, Monika; Biener, Jürgen; Hartmann, Nils

2016-06-01

Photothermal processing of nanoporous gold with a microfocused continuous-wave laser at λ = 532 nm provides a facile means in order engineer the pore and ligament size of nanoporous gold. In this report we take advantage of this approach in order to investigate the size-dependence of enhancement effects in surface-enhanced Raman spectroscopy (SERS). Surface structures with laterally varying pore sizes from 25 nm to ≥200 nm are characterized using scanning electron microscopy and then functionalized with N719, a commercial ruthenium complex, which is widely used in dye-sensitized solar cells. Raman spectroscopy reveals the characteristic spectral features of N719. Peak intensities strongly depend on the pore size. Highest intensities are observed on the native support, i.e. on nanoporous gold with pore sizes around 25 nm. These results demonstrate the particular perspectives of laser-fabricated nanoporous gold structures in fundamental SERS studies. In particular, it is emphasized that laser-engineered porous gold substrates represent a very well defined platform in order to study size-dependent effects with high reproducibility and precision and resolve conflicting results in previous studies.

Assault in children admitted to trauma centers: Injury patterns and outcomes from a 5-year review of the national trauma data bank.

PubMed

Barmparas, Galinos; Dhillon, Navpreet K; Smith, Eric J T; Tatum, James M; Chung, Rex; Melo, Nicolas; Ley, Eric J; Margulies, Daniel R

2017-07-01

While assault is commonly reported or suspected in children with traumatic wounds, a recent overview of these injuries, especially those requiring trauma surgery consultation is lacking in the literature. Explore the incidence, demographics and injury patterns of children presenting to trauma centers following an assault. Retrospective review of the National Trauma Data Bank 2007 to 2011. Subjects up to 18 years old with "assault" reported as the intent of injury. Patients were divided into infants (<2 years), young children (2-5 years), children (6-11 years), and adolescents (12-18 years). Mechanism of injury, injury severity and mortality based on age groups and race. Of 609,207 children, 58,299 (9.6%) were victims of an assault. The median age was 16 years and 81% were male, with a median injury severity score (ISS) of 8. The majority of patients were adolescents (76%), followed by infants (17%) and young children (4%). There was a stepwise increase in the proportion of assaulted Black children with increasing age (23.2% for infants and up to 46.7% for adolescents, trend p < 0.01, effect size: 0.175) while the opposite applied for White children (46.0% for infants and down to 19.5% for adolescents, trend p < 0.01, effect size: -0.230). With increasing age, White subjects had the highest trend of being assaulted during an unarmed fight or brawl (p < 0.01, effect size: 0.393), while for Black victims the highest trend was noted for assault with a firearm (p < 0.01, effect size: 0.323). Almost 2 out of 3 infants sustained severe head trauma (59%). The overall mortality was 8%, highest among young children, where it reached 16% (p < 0.01). Up to 10% of children admitted following trauma are victims of assault with traumatic brain injuries predominant in infants and firearm injuries predominant in adolescents. Injury patterns largely correlate to age and race. Assault in children is associated with a high mortality risk. These data highlight the magnitude of the problem and calls for further involvement of trauma surgeons to improve outcomes, bring awareness and promote preventative strategies to eliminate assault in children. Copyright © 2017 IJS Publishing Group Ltd. Published by Elsevier Ltd. All rights reserved.

Outplanting technique, host genotype, and site affect the initial success of outplanted Acropora cervicornis

PubMed Central

Gilliam, David S.

2018-01-01

Acropora cervicornis is the most widely used coral species for reef restoration in the greater Caribbean. However, outplanting methodologies (e.g., colony density, size, host genotype, and attachment technique) vary greatly, and to date have not been evaluated for optimality across multiple sites. Two experiments were completed during this study, the first evaluated the effects of attachment technique, colony size, and genotype by outplanting 405 A. cervicornis colonies, from ten genotypes, four size classes, and three attachment techniques (epoxy, nail and cable tie, or puck) across three sites. Colony survival, health condition, tissue productivity, and growth were assessed across one year for this experiment. The second experiment assessed the effect of colony density by outplanting colonies in plots of one, four, or 25 corals per 4 m2 across four separate sites. Plot survival and condition were evaluated across two years for this experiment in order to better capture the effect of increasing cover. Colonies attached with a nail and cable tie resulted in the highest survival regardless of colony size. Small corals had the lowest survival, but the greatest productivity. The majority of colony loss was attributed to missing colonies and was highest for pucks and small epoxied colonies. Disease and predation were observed at all sites, but did not affect all genotypes, however due to the overall low prevalence of either condition there were no significant differences found in any comparison. Low density plots had significantly higher survival and significantly lower prevalence of disease, predation, and missing colonies than high density plots. These results indicate that to increase initial outplant success, colonies of many genotypes should be outplanted to multiple sites using a nail and cable tie, in low densities, and with colonies over 15 cm total linear extension. PMID:29507829

Adsorption and release of biocides with mesoporous silica nanoparticles

NASA Astrophysics Data System (ADS)

Popat, Amirali; Liu, Jian; Hu, Qiuhong; Kennedy, Michael; Peters, Brenton; Lu, Gao Qing (Max); Qiao, Shi Zhang

2012-01-01

In this proof-of-concept study, an agricultural biocide (imidacloprid) was effectively loaded into the mesoporous silica nanoparticles (MSNs) with different pore sizes, morphologies and mesoporous structures for termite control. This resulted in nanoparticles with a large surface area, tunable pore diameter and small particle size, which are ideal carriers for adsorption and controlled release of imidacloprid. The effect of pore size, surface area and mesoporous structure on uptake and release of imidacloprid was systematically studied. It was found that the adsorption amount and release profile of imidacloprid were dependent on the type of mesoporous structure and surface area of particles. Specifically, MCM-48 type mesoporous silica nanoparticles with a three dimensional (3D) open network structure and high surface area displayed the highest adsorption capacity compared to other types of silica nanoparticles. Release of imidacloprid from these nanoparticles was found to be controlled over 48 hours. Finally, in vivo laboratory testing on termite control proved the efficacy of these nanoparticles as delivery carriers for biopesticides. We believe that the present study will contribute to the design of more effective controlled and targeted delivery for other biomolecules.In this proof-of-concept study, an agricultural biocide (imidacloprid) was effectively loaded into the mesoporous silica nanoparticles (MSNs) with different pore sizes, morphologies and mesoporous structures for termite control. This resulted in nanoparticles with a large surface area, tunable pore diameter and small particle size, which are ideal carriers for adsorption and controlled release of imidacloprid. The effect of pore size, surface area and mesoporous structure on uptake and release of imidacloprid was systematically studied. It was found that the adsorption amount and release profile of imidacloprid were dependent on the type of mesoporous structure and surface area of particles. Specifically, MCM-48 type mesoporous silica nanoparticles with a three dimensional (3D) open network structure and high surface area displayed the highest adsorption capacity compared to other types of silica nanoparticles. Release of imidacloprid from these nanoparticles was found to be controlled over 48 hours. Finally, in vivo laboratory testing on termite control proved the efficacy of these nanoparticles as delivery carriers for biopesticides. We believe that the present study will contribute to the design of more effective controlled and targeted delivery for other biomolecules. Electronic supplementary information (ESI) available. See DOI: 10.1039/c2nr11691j

Bioaccessibility and Cellular Uptake of β-Carotene Encapsulated in Model O/W Emulsions: Influence of Initial Droplet Size and Emulsifiers

PubMed Central

Kelly, Alan L.

2017-01-01

The effects of the initial emulsion structure (droplet size and emulsifier) on the properties of β-carotene-loaded emulsions and the bioavailability of β-carotene after passing through simulated gastrointestinal tract (GIT) digestion were investigated. Exposure to GIT significantly changed the droplet size, surface charge and composition of all emulsions, and these changes were dependent on their initial droplet size and the emulsifiers used. Whey protein isolate (WPI)-stabilized emulsion showed the highest β-carotene bioaccessibility, while sodium caseinate (SCN)-stabilized emulsion showed the highest cellular uptake of β-carotene. The bioavailability of emulsion-encapsulated β-carotene based on the results of bioaccessibility and cellular uptake showed the same order with the results of cellular uptake being SCN > TW80 > WPI. An inconsistency between the results of bioaccessibility and bioavailability was observed, indicating that the cellular uptake assay is necessary for a reliable evaluation of the bioavailability of emulsion-encapsulated compounds. The findings in this study contribute to a better understanding of the correlation between emulsion structure and the digestive fate of emulsion-encapsulated nutrients, which make it possible to achieve controlled or potential targeted delivery of nutrients by designing the structure of emulsion-based carriers. PMID:28930195

Effects of reclamation years on composition and diversity of soil bacterial communities in Northwest China.

PubMed

Cheng, Zhibo; Zhang, Fenghua; Gale, William Jeffrey; Wang, Weichao; Sang, Wen; Yang, Haichang

2018-01-01

The objective of this study was to evaluate bacterial community structure and diversity in soil aggregate fractions when salinized farmland was reclaimed after >27 years of abandonment and then farmed again for 1, 5, 10, and 15 years. Illumina MiSeq high-throughput sequencing was performed to characterize the soil bacterial communities in 5 aggregate size classes in each treatment. The results indicated that reclamation significantly increased macro-aggregation (>0.25 mm), as well as soil organic C, available N, and available P. The 10-year field had the largest proportion (93.9%) of soil in the macro-aggregate size classes (i.e., >0.25 mm) and the highest soil electrical conductivity. The 5 most dominant phyla in the soil samples were Proteobacteria, Actinobacteria, Gemmatimonadetes, Acidobacteria, and Bacteroidetes. The phylogenetic diversity, Chao1, and Shannon indices increased after the abandoned land was reclaimed for farming, reaching maximums in the 15-year field. Among aggregate size classes, the 1-0.25 mm aggregates generally had the highest phylogenetic diversity, Chao1, and Shannon indices. Soil organic C and soil electrical conductivity were the main environmental factors affecting the soil bacterial communities. The composition and structure of the bacterial communities also varied significantly depending on soil aggregate size and time since reclamation.

Determination of permeability of ultra-fine cupric oxide aerosol through military filters and protective filters

NASA Astrophysics Data System (ADS)

Kellnerová, E.; Večeřa, Z.; Kellner, J.; Zeman, T.; Navrátil, J.

2018-03-01

The paper evaluates the filtration and sorption efficiency of selected types of military combined filters and protective filters. The testing was carried out with the use of ultra-fine aerosol containing cupric oxide nanoparticles ranging in size from 7.6 nm to 299.6 nm. The measurements of nanoparticles were carried out using a scanning mobility particle sizer before and after the passage through the filter and a developed sampling device at the level of particle number concentration approximately 750000 particles·cm-3. The basic parameters of permeability of ultra-fine aerosol passing through the tested material were evaluated, in particular particle size, efficiency of nanoparticle capture by filter, permeability coefficient and overall filtration efficiency. Results indicate that the military filter and particle filters exhibited the highest aerosol permeability especially in the nanoparticle size range between 100–200 nm, while the MOF filters had the highest permeability in the range of 200 to 300 nm. The Filter Nuclear and the Health and Safety filter had 100% nanoparticle capture efficiency and were therefore the most effective. The obtained measurement results have shown that the filtration efficiency over the entire measured range of nanoparticles was sufficient; however, it was different for particular particle sizes.

Effects of crystal refining on wear behaviors and mechanical properties of lithium disilicate glass-ceramics.

PubMed

Zhang, Zhenzhen; Guo, Jiawen; Sun, Yali; Tian, Beimin; Zheng, Xiaojuan; Zhou, Ming; He, Lin; Zhang, Shaofeng

2018-05-01

The purpose of this study is to improve wear resistance and mechanical properties of lithium disilicate glass-ceramics by refining their crystal sizes. After lithium disilicate glass-ceramics (LD) were melted to form precursory glass blocks, bar (N = 40, n = 10) and plate (N = 32, n = 8) specimens were prepared. According to the differential scanning calorimetry (DSC) of precursory glass, specimens G1-G4 were designed to form lithium disilicate glass-ceramics with different crystal sizes using a two-step thermal treatment. In the meantime, heat-pressed lithium disilicate glass-ceramics (GC-P) and original ingots (GC-O) were used as control groups. Glass-ceramics were characterized using X-ray diffraction (XRD) and were tested using flexural strength test, nanoindentation test and toughness measurements. The plate specimens were dynamically loaded in a chewing simulator with 350 N up to 2.4 × 10 6 loading cycles. The wear analysis of glass-ceramics was performed using a 3D profilometer after every 300,000 wear cycles. Wear morphologies and microstructures were analyzed by scanning electron microscopy (SEM). One-way analysis of variance (ANOVA) was used to analyze the data. Multiple pairwise comparisons of means were performed by Tukey's post-hoc test. Materials with different crystal sizes (p < 0.05) exhibited different properties. Specifically, G3 with medium-sized crystals presented the highest flexural strength, hardness, elastic modulus and fracture toughness. G1 and G2 with small-sized crystals showed lower flexural strength, whereas G4, GC-P, and GC-O with large-sized crystals exhibited lower hardness and elastic modulus. The wear behaviors of all six groups showed running-in wear stage and steady wear stage. G3 showed the best wear resistance while GC-P and GC-O exhibited the highest wear volume loss. After crystal refining, lithium disilicate glass-ceramic with medium-sized crystals showed the highest wear resistance and mechanical properties. Copyright © 2018 Elsevier Ltd. All rights reserved.

Abundance, size and polymer composition of marine microplastics ≥10μm in the Atlantic Ocean and their modelled vertical distribution.

PubMed

Enders, Kristina; Lenz, Robin; Stedmon, Colin A; Nielsen, Torkel G

2015-11-15

We studied abundance, size and polymer type of microplastic down to 10μm along a transect from the European Coast to the North Atlantic Subtropical Gyre (NASG) using an underway intake filtration technique and Raman micro-spectrometry. Concentrations ranged from 13 to 501itemsm(-3). Highest concentrations were observed at the European coast, decreasing towards mid-Atlantic waters but elevated in the western NASG. We observed highest numbers among particles in the 10-20μm size fraction, whereas the total volume was highest in the 50-80μm range. Based on a numerical model size-dependent depth profiles of polyethylene microspheres in a range from 10-1000μm were calculated and show a strong dispersal throughout the surface mixed layer for sizes smaller than 200μm. From model and field study results we conclude that small microplastic is ubiquitously distributed over the ocean surface layer and has a lower residence time than larger plastic debris in this compartment. Copyright © 2015 Elsevier Ltd. All rights reserved.

[Studies on the size distribution of airborne microbes at home in Beijing].

PubMed

Fang, Zhi-Guo; Sun, Ping; Ouyang, Zhi-Yun; Liu, Peng; Sun, Li; Wang, Xiao-Yong

2013-07-01

The effect of airborne microbes on human health not only depends on their compositions (genera and species), but also on their concentrations and sizes. Moreover, there are different mechanisms of airborne microbes of different sizes with different effects on human health. The size distributions and median diameters were investigated in detail with imitated six-stage Andersen sampler in 31 selected family homes with children in Beijing. Results showed that there was similar distribution characteristics of airborne microbes in different home environment, different season, different child's sex, and different apartment's architecture, but different distribution characteristics between airborne bacteria and fungi were observed in family homes in Beijing. In general, although airborne bacteria and fungi were plotted with normal logarithmic distribution, the particle percentage of airborne bacteria increased gradually from stage 1 (> 8.2 microm) to stage 5 (1.0-2.0 microm), and then decreased dramatically in stage 6 (< 1.0 microm), the percentage of airborne fungi increased gradually from stage 1 to stage 4 (2.0-3.5 microm), and then decreased dramatically from stage 4 to stage 6. The size distributions of dominant fungi were different in different fungal genera. Cladosporium, Penicillium and Aspergillus were recorded with normal logarithmic distribution, with the highest percentage detected in stage 4, and Alternaria were observed with skew distribution, with the highest percentage detected in stage 2 (5.0-10.4 microm). Finally, the median diameters of airborne bacteria were larger than those of airborne fungi, and the lowest median diameter of airborne bacteria and fungi was found in winter, while there were no significant variations of airborne bacterial and fungal median diameters in spring, summer and autumn in a year in this study.

Mineralogical, chemical and toxicological characterization of urban air particles.

PubMed

Čupr, Pavel; Flegrová, Zuzana; Franců, Juraj; Landlová, Linda; Klánová, Jana

2013-04-01

Systematic characterization of morphological, mineralogical, chemical and toxicological properties of various size fractions of the atmospheric particulate matter was a main focus of this study together with an assessment of the human health risks they pose. Even though near-ground atmospheric aerosols have been a subject of intensive research in recent years, data integrating chemical composition of particles and health risks are still scarce and the particle size aspect has not been properly addressed yet. Filling this gap, however, is necessary for reliable risk assessment. A high volume ambient air sampler equipped with a multi-stage cascade impactor was used for size specific particle collection, and all 6 fractions were a subject of detailed characterization of chemical (PAHs) and mineralogical composition of the particles, their mass size distribution and genotoxic potential of organic extracts. Finally, the risk level for inhalation exposure associated to the carcinogenic character of the studied PAHs has been assessed. The finest fraction (<0.45 μm) exhibited the highest mass, highest active surface, highest amount of associated PAHs and also highest direct and indirect genotoxic potentials in our model air sample. Risk assessment of inhalation scenario indicates the significant cancer risk values in PM 1.5 size fraction. This presented new approach proved to be a useful tool for human health risk assessment in the areas with significant levels of air dust concentration. Copyright © 2013 Elsevier Ltd. All rights reserved.

Effects of Word Width and Word Length on Optimal Character Size for Reading of Horizontally Scrolling Japanese Words

PubMed Central

Teramoto, Wataru; Nakazaki, Takuyuki; Sekiyama, Kaoru; Mori, Shuji

2016-01-01

The present study investigated, whether word width and length affect the optimal character size for reading of horizontally scrolling Japanese words, using reading speed as a measure. In Experiment 1, three Japanese words, each consisting of four Hiragana characters, sequentially scrolled on a display screen from right to left. Participants, all Japanese native speakers, were instructed to read the words aloud as accurately as possible, irrespective of their order within the sequence. To quantitatively measure their reading performance, we used rapid serial visual presentation paradigm, where the scrolling rate was increased until the participants began to make mistakes. Thus, the highest scrolling rate at which the participants’ performance exceeded 88.9% correct rate was calculated for each character size (0.3°, 0.6°, 1.0°, and 3.0°) and scroll window size (5 or 10 character spaces). Results showed that the reading performance was highest in the range of 0.6° to 1.0°, irrespective of the scroll window size. Experiment 2 investigated whether the optimal character size observed in Experiment 1 was applicable for any word width and word length (i.e., the number of characters in a word). Results showed that reading speeds were slower for longer than shorter words and the word width of 3.6° was optimal among the word lengths tested (three, four, and six character words). Considering that character size varied depending on word width and word length in the present study, this means that the optimal character size can be changed by word width and word length in scrolling Japanese words. PMID:26909052

Effects of Word Width and Word Length on Optimal Character Size for Reading of Horizontally Scrolling Japanese Words.

PubMed

Teramoto, Wataru; Nakazaki, Takuyuki; Sekiyama, Kaoru; Mori, Shuji

2016-01-01

The present study investigated, whether word width and length affect the optimal character size for reading of horizontally scrolling Japanese words, using reading speed as a measure. In Experiment 1, three Japanese words, each consisting of four Hiragana characters, sequentially scrolled on a display screen from right to left. Participants, all Japanese native speakers, were instructed to read the words aloud as accurately as possible, irrespective of their order within the sequence. To quantitatively measure their reading performance, we used rapid serial visual presentation paradigm, where the scrolling rate was increased until the participants began to make mistakes. Thus, the highest scrolling rate at which the participants' performance exceeded 88.9% correct rate was calculated for each character size (0.3°, 0.6°, 1.0°, and 3.0°) and scroll window size (5 or 10 character spaces). Results showed that the reading performance was highest in the range of 0.6° to 1.0°, irrespective of the scroll window size. Experiment 2 investigated whether the optimal character size observed in Experiment 1 was applicable for any word width and word length (i.e., the number of characters in a word). Results showed that reading speeds were slower for longer than shorter words and the word width of 3.6° was optimal among the word lengths tested (three, four, and six character words). Considering that character size varied depending on word width and word length in the present study, this means that the optimal character size can be changed by word width and word length in scrolling Japanese words.

[Nitrogen Fraction Distributions and Impacts on Soil Nitrogen Mineralization in Different Vegetation Restorations of Karst Rocky Desertification].

PubMed

Hu, Ning; Ma, Zhi-min; Lan, Jia-cheng; Wu, Yu-chun; Chen, Gao-qi; Fu, Wa-li; Wen, Zhi-lin; Wang, Wen-jing

2015-09-01

In order to illuminate the impact on soil nitrogen accumulation and supply in karst rocky desertification area, the distribution characteristics of soil nitrogen pool for each class of soil aggregates and the relationship between aggregates nitrogen pool and soil nitrogen mineralization were analyzed in this study. The results showed that the content of total nitrogen, light fraction nitrogen, available nitrogen and mineral nitrogen in soil aggregates had an increasing tendency along with the descending of aggregate-size, and the highest content was occurred in < 0. 25 mm. The content of nitrogen fractions for all aggregate-classes followed in the order of abandoned land < grass land < brush land < brush-arbor land < arbor land in different sample plots. Artificial forest lands had more effects on the improvement of the soil nitrogen than honeysuckle land. In this study it also showed the nitrogen stockpiling quantity of each aggregate-size class was differed in all aggregate-size classes, in which the content of nitrogen fraction in 5-10 mm and 2-5 mm classes of soil aggregate-size were the highest. And it meant that soil nutrient mainly was stored in large size aggregates. Large size aggregates were significant to the storage of soil nutrient. For each class of soil aggregate-size, the contribution of the nitrogen stockpiling quantity of 0. 25-1 mm class to soil net nitrogen mineralization quantity was the biggest, and following >5mm and 2-5 mm classes, and the others were the smallest. With the positive vegetation succession, the weight percentage of > 5 mm aggregate-size classes was improved and the nitrogen storage of macro-aggregates also was increased. Accordingly, the capacity of soil supply mineral nitrogen and storage organic nitrogen were intensified.

Regional Differences in Case Mix and Peri-operative Outcome After Elective Abdominal Aortic Aneurysm Repair in the Vascunet Database.

PubMed

Mani, K; Venermo, M; Beiles, B; Menyhei, G; Altreuther, M; Loftus, I; Björck, M

2015-06-01

National differences exist in the outcome of elective abdominal aortic aneurysm (AAA) repair. The role of case mix variation was assessed based on an international vascular registry collaboration. All elective AAA repairs with aneurysm size data in the Vascunet database in the period 2005-09 were included. AAA size and peri-operative outcome (crude and age adjusted mortality) were analysed overall and in risk cohorts, as well as per country. Glasgow Aneurysm Score (GAS) was calculated as risk score, and patients were stratified in three equal sized risk cohorts based on GAS. Predictors of peri-operative mortality were analysed with multiple regression. Missing data were handled with multiple imputation. Patients from Australia, Finland, Hungary, Norway, Sweden and the UK (n = 5,895) were analysed; mean age was 72.7 years and 54% had endovascular repair (EVAR). There were significant variations in GAS (lowest = Finland [75.7], highest = UK [79.4], p for comparison of all regions < .001), proportion of AAA < 5.5 cm (lowest = UK [6.4%], highest = Hungary [29.0%]; p < .001), proportion undergoing EVAR (lowest = Finland [10.1%], highest = Australia [58.9%]; p < .001), crude mortality (lowest = Norway [2.0%], highest = Finland [5.0%]; p = .006), and age adjusted mortality (lowest = Norway [2.5%], highest = Finland [6.0%]; p = .048). Both aneurysm size and peri-operative mortality were highest among patients with a GAS >82. Of those with a GAS >82, 8.4% of men and 20.8% of women had an AAA <5.5 cm. Important regional differences exist in case selection for elective AAA repair, including variations in AAA size and patient risk profile. These differences partly explain the variations in peri-operative mortality. Further audit is warranted to assess the underlying reasons for the regional variation in case-mix. Copyright © 2015 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.

Measurement of In Vivo Three-Dimensional Corneal Cell Density and Size Using Two-Photon Imaging in C57BL/6 Mice.

PubMed

Zhang, Hongmin; He, Siyu; Liu, Susu; Xie, Yanting; Chen, Guoming; Zhang, Junjie; Sun, Shengtao; Liang, David; Wang, Liya

2016-04-01

To measure the cell size and cell density in five layers of the central cornea in the widely used inbred C57BL/6 mouse strain using in vivo three-dimensional (3D) two-photon (2PH) imaging. Corneas were scanned using a 2PH laser scanning fluorescence microscope after staining with plasma membrane stain and Hoechst 33342. Good quality 3D images were selected for the cell density and cell size analysis. Cell density was determined by counting the cell nuclei in a predefined cube of 3D images. Cell size measurements, including cell surface area, cell volume, nuclear surface area and nuclear volume, were automatically quantified using the Imaris software. The cell and nuclear surface-area-to-volume ratio (S:V ratio) and the cell nuclear-cytoplasmic ratio (N:C ratio) were calculated. The highest cell density was observed in the basal epithelium and the lowest in the posterior stroma. The highest cell surface area was found in the anterior stroma, and the highest cell volume was observed in the superficial epithelium. The lowest cell surface area and cell volume were both found in the basal epithelium. The highest S:V ratio was observed in the basal epithelium and the lowest in the superficial epithelium. The highest cell nuclear surface area and volume were both observed in the superficial epithelium and the lowest in the basal epithelium. The highest cell nuclear S:V ratio was observed in the basal epithelium and the lowest in the superficial epithelium. The highest N:C ratio was found in the basal epithelial cells and the lowest in the posterior keratocytes. We are the first to quantify the cell density and size parameters, including cell surface area and volume, cell nuclear surface area and volume, and the S:V ratio, in the five layers of the central cornea. These data provide important cell morphology features for the study of corneal physiology, pathology and disease in mice, particularly in C57BL/6 mice.

Migrants, healthy worker effect, and mortality trends in the Gulf Cooperation Council countries.

PubMed

Chaabna, Karima; Cheema, Sohaila; Mamtani, Ravinder

2017-01-01

The Gulf Cooperation Council (GCC) countries namely, Bahrain, Kuwait, Oman, Qatar, United Arab Emirates (UAE), and Saudi Arabia, have experienced unique demographic changes. The major population growth contributor in these countries is young migrants, which has led to a shift in the population age pyramid. Migrants constitute the vast proportion of GCC countries' population reaching >80% in Qatar and UAE. Using Global Burden of Disease Study 2015 (GBD 2015) and United Nations data, for the GCC countries, we assessed the association between age-standardized mortality and population size trends with linear and polynomial regressions. In 1990-2015, all-cause age-standardized mortality was inversely proportional to national population size (p-values: 0.0001-0.0457). In Bahrain, Qatar, Oman, and Saudi Arabia, the highest annual decrease in mortality was observed when the annual population growth was the highest. In Qatar, all-cause age-specific mortality was inversely proportional to age-specific population size. This association was statistically significant among the 5-14 and 15-49 age groups, which have the largest population size. Cause-specific age-standardized mortality was also inversely proportional to population size. This association was statistically significant for half of the GBD 2015-defined causes of death such as "cirrhosis and other chronic liver diseases" and "HIV/AIDS and tuberculosis". Remarkably, incoming migrants to Qatar have to be negative for HIV, hepatitis B and C, and tuberculosis. These results show that decline in mortality can be partly attributed to the increase in GCC countries' population suggesting a healthy migrant effect that influences mortality rates. Consequently, benefits of health interventions and healthcare improvement are likely to be exaggerated in such countries hosting a substantial proportion of migrants compared with countries where migration is low. Researchers and policymakers should be cautious to not exclusively attribute decline in mortality within the GCC countries as a result of the positive effects of health interventions or healthcare improvement.

Migrants, healthy worker effect, and mortality trends in the Gulf Cooperation Council countries

PubMed Central

Cheema, Sohaila; Mamtani, Ravinder

2017-01-01

The Gulf Cooperation Council (GCC) countries namely, Bahrain, Kuwait, Oman, Qatar, United Arab Emirates (UAE), and Saudi Arabia, have experienced unique demographic changes. The major population growth contributor in these countries is young migrants, which has led to a shift in the population age pyramid. Migrants constitute the vast proportion of GCC countries’ population reaching >80% in Qatar and UAE. Using Global Burden of Disease Study 2015 (GBD 2015) and United Nations data, for the GCC countries, we assessed the association between age-standardized mortality and population size trends with linear and polynomial regressions. In 1990–2015, all-cause age-standardized mortality was inversely proportional to national population size (p-values: 0.0001–0.0457). In Bahrain, Qatar, Oman, and Saudi Arabia, the highest annual decrease in mortality was observed when the annual population growth was the highest. In Qatar, all-cause age-specific mortality was inversely proportional to age-specific population size. This association was statistically significant among the 5–14 and 15–49 age groups, which have the largest population size. Cause-specific age-standardized mortality was also inversely proportional to population size. This association was statistically significant for half of the GBD 2015-defined causes of death such as “cirrhosis and other chronic liver diseases” and “HIV/AIDS and tuberculosis”. Remarkably, incoming migrants to Qatar have to be negative for HIV, hepatitis B and C, and tuberculosis. These results show that decline in mortality can be partly attributed to the increase in GCC countries’ population suggesting a healthy migrant effect that influences mortality rates. Consequently, benefits of health interventions and healthcare improvement are likely to be exaggerated in such countries hosting a substantial proportion of migrants compared with countries where migration is low. Researchers and policymakers should be cautious to not exclusively attribute decline in mortality within the GCC countries as a result of the positive effects of health interventions or healthcare improvement. PMID:28632794

Influence of fundamental mode fill factor on disk laser output power and laser beam quality

NASA Astrophysics Data System (ADS)

Cheng, Zhiyong; Yang, Zhuo; Shao, Xichun; Li, Wei; Zhu, Mengzhen

2017-11-01

An three-dimensional numerical model based on finite element method and Fox-Li method with angular spectrum diffraction theoy is developed to calculate the output power and power density distribution of Yb:YAG disk laser. We invest the influence of fundamental mode fill factor(the ratio of fundamental mode size and pump spot size) on the output power and laser beam quality. Due to aspherical aberration and soft aperture effect in laser disk, high beam quality can be achieve with relative lower efficiency. The highest output power of fundamental laser mode is influenced by the fundamental mode fill factor. Besides we find that optimal mode fill factor increase with pump spot size.

The size seems to matter or where lies the “asymptopia”?

NASA Astrophysics Data System (ADS)

Petrov, V. A.; Okorokov, V. A.

2018-05-01

We discuss an apparent correlation between the onset of the rising regime for the total cross-sections and the slowdown of the rise of the forward slopes with energy. It is shown that even at highest energies achieved with the large hadron collider (LHC) the proper sizes of the colliding protons comprise the bulk of the interaction region. This seems to witness that the “asymptopia” — a hypothetical “truly asymptotic” regime — lies at energies no less than 𝒪 (100 TeV). In the course of reasoning, we also discuss the question of the dependence of the effective sizes of hadrons in collision on the type of their interaction.

Effect of binary organic solvents together with emulsifier on particle size and in vitro behavior of paclitaxel-encapsulated polymeric lipid nanoparticles.

PubMed

Qin, Shuzhi; Sun, Xiangshi; Li, Feng; Yu, Kongtong; Zhou, Yulin; Liu, Na; Zhao, Chengguo; Teng, Lesheng; Li, Youxin

2017-12-21

Biodegradable nanoparticles with diameters between 100 nm and 500 nm are of great interest in the contexts of targeted delivery. The present work provides a review concerning the effect of binary organic solvents together with emulsifier on particle size as well as the influence of particle size on the in vitro drug release and uptake behavior. The polymeric lipid nanoparticles (PLNs) with different particle sizes were prepared by using binary solvent dispersion method. Various formulation parameters such as binary organic solvent composition and emulsifier types were evaluated on the basis of their effects on particle size and size distribution. PLNs had a strong dependency on the surface tension, intrinsic viscosity and volatilization rate of binary organic solvents and the hydrophilicity/hydrophobicity of emulsifiers. Acetone-methanol system together with pluronic F68 as emulsifier was proved to obtain the smallest particle size. Then the PLNs with different particle sizes were used to investigate how particle size at nanoscale affects interacted with tumor cells. As particle size got smaller, cellular uptake increased in tumor cells and PLNs with particle size of ~120 nm had the highest cellular uptake and fastest release rate. The paclitaxel (PTX)-loaded PLNs showed a size-dependent inhibition of tumor cell growth, which was commonly influenced by cellular uptake and PTX release. The PLNs would provide a useful means to further elucidate roles of particle size on delivery system of hydrophobic drugs. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Which is the Ideal Breast Size?: Some Social Clues for Plastic Surgeons.

PubMed

Raposio, Edoardo; Belgrano, Valerio; Santi, PierLuigi; Chiorri, Carlo

2016-03-01

To provide plastic surgeons with more detailed information as to factors affecting the perception of female attractiveness, the present study was aimed to investigate whether the interaction effect of breast and body size on ratings of female attractiveness is moderated by sociodemographic variables and whether ratings of shapeliness diverge from those of attractiveness.A community sample of 958 Italian participants rated the attractiveness and the shapeliness of 15 stimuli (5 breast sizes × 3 body sizes) in which frontal, 3/4, and profile views of the head and torso of a faceless woman were jointly shown.Bigger breast sizes obtained the highest attractiveness ratings, but the breast-by-body size interaction was also significant. Evidence was found of a moderator role of sex, marital status, and age. When the effects of breast and body size and their interaction had been ruled out, sex differences were at best very slight and limited to very specific combinations of breast and body sizes. Ratings of attractiveness and shapeliness were highly correlated and did not significantly differ.Results suggest that to address women's psychological needs, concerns, and expectations about their appearance, plastic surgeons should not simply focus on breast size but should carefully consider the 'big picture': the body in its entirety.

Size effects in electronic and catalytic properties of unsupported palladium nanoparticles in electrooxidation of formic acid.

PubMed

Zhou, Wei Ping; Lewera, Adam; Larsen, Robert; Masel, Rich I; Bagus, Paul S; Wieckowski, Andrzej

2006-07-13

We report a combined X-ray photoelectron spectroscopy (XPS), cyclic voltammetry (CV), and chronoamperometry (CA) study of formic acid electrooxidation on unsupported palladium nanoparticle catalysts in the particle size range from 9 to 40 nm. The CV and CA measurements show that the most active catalyst is made of the smallest (9 and 11 nm) Pd nanoparticles. Besides the high reactivity, XPS data show that such nanoparticles display the highest core-level binding energy (BE) shift and the highest valence band (VB) center downshift with respect to the Fermi level. We believe therefore that we found a correlation between formic acid oxidation current and BE and VB center shifts, which, in turn, can directly be related to the electronic structure of palladium nanoparticles of different particle sizes. Clearly, such a trend using unsupported catalysts has never been reported. According to the density functional theory of heterogeneous catalysis, and mechanistic considerations, the observed shifts are caused by a weakening of the bond strength of the COOH intermediate adsorption on the catalyst surface. This, in turn, results in the increase in the formic acid oxidation rate to CO2 (and in the associated oxidation current). Overall, our measurements demonstrate the particle size effect on the electronic properties of palladium that yields different catalytic activity in the HCOOH oxidation reaction. Our work highlights the significance of the core-level binding energy and center of the d-band shifts in electrocatalysis and underlines the value of the theory that connects the center of the d-band shifts to catalytic reactivity.

Positivity and indicators of health among African Americans with diabetes.

PubMed

Steinhardt, Mary A; Dubois, Susan K; Brown, Sharon A; Harrison, Louis; Dolphin, Kathryn E; Park, Wonil; Lehrer, H Matthew

2015-01-01

To examine the utility of the positivity ratio to distinguish differences in psychological and physiological health in African Americans with type 2 diabetes. Study participants (N = 93) were recruited through radio and church announcements and grouped by their positivity ratio. Multivariate analyses showed flourishing individuals had the highest resilience and lowest depressive symptoms and HbA1c (A1C), whereas depressed individuals recorded the lowest resilience and highest depressive symptoms and A1C. Small to large effect sizes were reported. Further support for the utility and generalizability of the positivity ratio was provided. Cultivating positive emotions may improve the health of individuals with type 2 diabetes.

Succinic Acid Production from Cheese Whey using Actinobacillus succinogenes 130 Z

NASA Astrophysics Data System (ADS)

Wan, Caixia; Li, Yebo; Shahbazi, Abolghasem; Xiu, Shuangning

Actinobacillus succinogenes 130 Z was used to produce succinic acid from cheese whey in this study. At the presence of external CO2 supply, the effects of initial cheese whey concentration, pH, and inoculum size on the succinic acid production were studied. The by-product formation during the fermentation process was also analyzed. The highest succinic acid yield of 0.57 was obtained at initial cheese whey concentration of 50 g/L, while the highest succinic acid productivity of 0.58 g h-1 L-1 was obtained at initial cheese whey concentration of 100 g/L. Increase in pH and inoculum size caused higher succinic acid yield and productivity. At the preferred fermentation condition of pH 6.8, inoculum size of 5% and initial cheese whey concentration of 50 g/L, succinic acid yield of 0.57, and productivity of 0.44 g h-1 L-1 were obtained. Acetic acid and formic acid were the main by-products throughout the fermentation run of 48 h. It is feasible to produce succinic acid using lactose from cheese whey as carbon resource by A. succinogenes 130 Z.

Effect of Powder Grain Size on Microstructure and Magnetic Properties of Hexagonal Barium Ferrite Ceramic

NASA Astrophysics Data System (ADS)

Shao, Li-Huan; Shen, Si-Yun; Zheng, Hui; Zheng, Peng; Wu, Qiong; Zheng, Liang

2018-05-01

Compact hexagonal barium ferrite (BaFe12O19, BaM) ceramics with excellent magnetic properties have been prepared from powder with the optimal grain size. The dependence of the microstructure and magnetic properties of the ceramics on powder grain size was studied in detail. Single-phase hexagonal barium ferrite powder with grain size of 177 nm, 256 nm, 327 nm, and 454 nm was obtained by calcination under different conditions. Scanning electron microscopy revealed that 327-nm powder was beneficial for obtaining homogeneous grain size and compact ceramic. In addition, magnetic hysteresis loops and complex permeability spectra demonstrated that the highest saturation magnetization (67.2 emu/g) and real part of the permeability (1.11) at 1 GHz were also obtained using powder with grain size of 327 nm. This relationship between the powder grain size and the properties of the resulting BaM ceramic could be significant for development of microwave devices.

Schedule-induced drinking as functions of interpellet interval and draught size in the Java macaque1

PubMed Central

Allen, Joseph D.; Kenshalo, Dan R.

1978-01-01

Three Java monkeys received food pellets that were assigned by both ascending and descending series of fixed-time schedules whose values varied between 8 and 256 seconds. The draught size dispensed by a concurrently available water-delivery tube was systematically varied between 1.0 and 0.3 milliliter per lick at various fixed-time values during the second and third series determinations. Session water intake was bitonically related to the interpellet interval and was determined by the interaction of (1) the probability of initiating a drinking bout, which fell off at the highest interpellet intervals and, (2) the size of the bout, which increased directly with increases in interpellet interval. Variations in draught size had little effect on total session intakes, but reduced bout size at draught sizes of 0.5 milliliter and below. Thus, a volume-regulation process of schedule-induced drinking operated generally at the session-intake level, but was limited to higher draught sizes at the bout level. PMID:16812093

Schedule-induced drinking as functions of interpellet interval and draught size in the Java macaque.

PubMed

Allen, J D; Kenshalo, D R

1978-09-01

Three Java monkeys received food pellets that were assigned by both ascending and descending series of fixed-time schedules whose values varied between 8 and 256 seconds. The draught size dispensed by a concurrently available water-delivery tube was systematically varied between 1.0 and 0.3 milliliter per lick at various fixed-time values during the second and third series determinations. Session water intake was bitonically related to the interpellet interval and was determined by the interaction of (1) the probability of initiating a drinking bout, which fell off at the highest interpellet intervals and, (2) the size of the bout, which increased directly with increases in interpellet interval. Variations in draught size had little effect on total session intakes, but reduced bout size at draught sizes of 0.5 milliliter and below. Thus, a volume-regulation process of schedule-induced drinking operated generally at the session-intake level, but was limited to higher draught sizes at the bout level.

Copper cluster size effect in methanol synthesis from CO 2

DOE PAGES

Yang, Bing; Liu, Cong; Halder, Avik; ...

2017-05-08

Here, size-selected Cu n catalysts ( n = 3, 4, 20) were synthesized on Al 2O 3 thin films using mass-selected cluster deposition. A systematic study of size and support effects was carried out for CO 2 hydrogenation at atmospheric pressure using a combination of in situ grazing incidence X-ray absorption spectroscopy, catalytic activity measurement, and first-principles calculations. The catalytic activity for methanol synthesis is found to strongly vary as a function of the cluster size; the Cu 4/Al 2O 3 catalyst shows the highest turnover rate for CH 3OH production. With only one atom less than Cu 4, Cumore » 3 showed less than 50% activity. Density functional theory calculations predict that the activities of the gas-phase Cu clusters increase as the cluster size decreases; however, the stronger charge transfer interaction with Al 2O 3 support for Cu 3 than for Cu 4 leads to remarkably reduced binding strength between the adsorbed intermediates and supported Cu 3, which subsequently results in a less favorable energetic pathway to transform carbon dioxide to methanol.« less

Roles of size and kinematics in drag reduction for two tandem flexible foils

NASA Astrophysics Data System (ADS)

Chao, Li-Ming; Zhang, Dong; Pan, Guang

2017-11-01

The effect of size and kinematics difference between two tandem flexible foils on drag reduction have been numerically studied. Compared with single foil, it is found that the kinematics difference between two foils would not play a significant role in reducing drag, while the size difference between two foils significantly affects the drag reduction in this two foil system. For leading foil, it always enjoys drag reduction and the highest drag reduction can be observed at bigger size difference and gap distance between two foil as 22%. For trailing foil, it suffers drag increase when the gap distance between two foils is smaller, while it enjoys drag decrease when the size difference between two foils is bigger enough. The hydrodynamic interaction between such actively undulated foils also has been uncovered and used to explain the mechanisms of drag reduction.

Martian particle size based on thermal inertia corrected for elevation-dependent atmospheric properties

NASA Technical Reports Server (NTRS)

Bridges, N. T.

1993-01-01

Thermal inertia is commonly used to derive physical properties of the Martian surface. If the surface is composed of loosely consolidated grains, then the thermal conductivity derived from the inertia can theoretically be used to compute the particle size. However, one persistent difficulty associated with the interpretation of thermal inertia and the derivation of particle size from it has been the degree to which atmospheric properties affect both the radiation balance at the surface and the gas conductivity. These factors vary with atmospheric pressure so that derived thermal inertias and particle sizes are a function of elevation. By utilizing currently available thermal models and laboratory information, a fine component thermal inertia map was convolved with digital topography to produce particle size maps of the Martian surface corrected for these elevation-dependent effects. Such an approach is especially applicable for the highest elevations on Mars, where atmospheric back radiation and gas conductivity are low.

Improving the toughness of ultrahigh strength steel

NASA Astrophysics Data System (ADS)

Sato, Koji

2002-01-01

The ideal structural steel combines high strength with high fracture toughness. This dissertation discusses the toughening mechanism of the Fe/Co/Ni/Cr/Mo/C steel, AerMet 100, which has the highest toughness/strength combination among all commercial ultrahigh strength steels. The possibility of improving the toughness of this steel was examined by considering several relevant factors. Chapter 1 reviews the mechanical properties of ultrahigh strength steels and the physical metallurgy of AerMet 100. It also describes the fracture mechanisms of steel, i.e. ductile microvoid coalescence, brittle transgranular cleavage, and intergranular separation. Chapter 2 examines the strength-toughness relationship for three heats of AerMet 100. A wide variation of toughness is obtained at the same strength level. The toughness varies despite the fact that all heat fracture in the ductile fracture mode. The difference originates from the inclusion content. Lower inclusion volume fraction and larger inclusion spacing gives rise to a greater void growth factor and subsequently a higher fracture toughness. The fracture toughness value, JIc, is proportional to the particle spacing of the large non-metallic inclusions. Chapter 3 examines the ductile-brittle transition of AerMet 100 and the effect of a higher austenitization temperature, using the Charpy V-notch test. The standard heat treatment condition of AerMet 100 shows a gradual ductile-brittle transition due to its fine effective grain size. Austenitization at higher temperature increases the prior austenite grain size and packet size, leading to a steeper transition at a higher temperature. Both transgranular cleavage and intergranular separation are observed in the brittle fracture mode. Chapter 4 examines the effect of inclusion content, prior austenite grain size, and the amount of austenite on the strength-toughness relationship. The highest toughness is achieved by low inclusion content, small prior austenite grain size, and a small content of stable austenite. The low inclusion content increases the strain at the fracture. The reduction in prior austenite grain size prevents the fast unstable crack propagation by cleavage. And the stable austenite decreases the strength of the intergranular separation at the prior austenite grain boundary, which provides the stress relief at the crack tip.

Paraprofessional-delivered home-visiting intervention for American Indian teen mothers and children: 3-year outcomes from a randomized controlled trial.

PubMed

Barlow, Allison; Mullany, Britta; Neault, Nicole; Goklish, Novalene; Billy, Trudy; Hastings, Ranelda; Lorenzo, Sherilynn; Kee, Crystal; Lake, Kristin; Redmond, Cleve; Carter, Alice; Walkup, John T

2015-02-01

The Affordable Care Act provides funding for home-visiting programs to reduce health care disparities, despite limited evidence that existing programs can overcome implementation and evaluation challenges with at-risk populations. The authors report 36-month outcomes of the paraprofessional-delivered Family Spirit home-visiting intervention for American Indian teen mothers and children. Expectant American Indian teens (N=322, mean age=18.1 years) from four southwestern reservation communities were randomly assigned to the Family Spirit intervention plus optimized standard care or optimized standard care alone. Maternal and child outcomes were evaluated at 28 and 36 weeks gestation and 2, 6, 12, 18, 24, 30, and 36 months postpartum. At baseline the mothers had high rates of substance use (>84%), depressive symptoms (>32%), dropping out of school (>57%), and residential instability (51%). Study retention was ≥83%. From pregnancy to 36 months postpartum, mothers in the intervention group had significantly greater parenting knowledge (effect size=0.42) and parental locus of control (effect size=0.17), fewer depressive symptoms (effect size=0.16) and externalizing problems (effect size=0.14), and lower past month use of marijuana (odds ratio=0.65) and illegal drugs (odds ratio=0.67). Children in the intervention group had fewer externalizing (effect size=0.23), internalizing (effect size=0.23), and dysregulation (effect size=0.27) problems. The paraprofessional home-visiting intervention promoted effective parenting, reduced maternal risks, and improved child developmental outcomes in the U.S. population subgroup with the fewest resources and highest behavioral health disparities. The methods and results can inform federal efforts to disseminate and sustain evidence-based home-visiting interventions in at-risk populations.

Day and night variation in chemical composition and toxicological responses of size segregated urban air PM samples in a high air pollution situation

NASA Astrophysics Data System (ADS)

Jalava, P. I.; Wang, Q.; Kuuspalo, K.; Ruusunen, J.; Hao, L.; Fang, D.; Väisänen, O.; Ruuskanen, A.; Sippula, O.; Happo, M. S.; Uski, O.; Kasurinen, S.; Torvela, T.; Koponen, H.; Lehtinen, K. E. J.; Komppula, M.; Gu, C.; Jokiniemi, J.; Hirvonen, M.-R.

2015-11-01

Urban air particulate pollution is a known cause for adverse human health effects worldwide. China has encountered air quality problems in recent years due to rapid industrialization. Toxicological effects induced by particulate air pollution vary with particle sizes and season. However, it is not known how distinctively different photochemical activity and different emission sources during the day and the night affect the chemical composition of the PM size ranges and subsequently how it is reflected to the toxicological properties of the PM exposures. The particulate matter (PM) samples were collected in four different size ranges (PM10-2.5; PM2.5-1; PM1-0.2 and PM0.2) with a high volume cascade impactor. The PM samples were extracted with methanol, dried and thereafter used in the chemical and toxicological analyses. RAW264.7 macrophages were exposed to the particulate samples in four different doses for 24 h. Cytotoxicity, inflammatory parameters, cell cycle and genotoxicity were measured after exposure of the cells to particulate samples. Particles were characterized for their chemical composition, including ions, element and PAH compounds, and transmission electron microscopy (TEM) was used to take images of the PM samples. Chemical composition and the induced toxicological responses of the size segregated PM samples showed considerable size dependent differences as well as day to night variation. The PM10-2.5 and the PM0.2 samples had the highest inflammatory potency among the size ranges. Instead, almost all the PM samples were equally cytotoxic and only minor differences were seen in genotoxicity and cell cycle effects. Overall, the PM0.2 samples had the highest toxic potential among the different size ranges in many parameters. PAH compounds in the samples and were generally more abundant during the night than the day, indicating possible photo-oxidation of the PAH compounds due to solar radiation. This was reflected to different toxicity in the PM samples. Some of the day to night difference may have been caused also by differing wind directions transporting air masses from different emission sources during the day and the night. The present findings indicate the important role of the local particle sources and atmospheric processes on the health related toxicological properties of the PM. The varying toxicological responses evoked by the PM samples showed the importance of examining various particle sizes. Especially the detected considerable toxicological activity by PM0.2 size range suggests they're attributable to combustion sources, new particle formation and atmospheric processes.

Seedbed Density Affects Size of 3-0 Green Ash Nursery Stock

Treesearch

J.H. Stoeckeler

1967-01-01

Nursery seedbed density of 3-0 green ash, which ranged from 4 to 36 trees per square foot at Carlos Avery Nursery, Forest Lake, Minn., had a marked effect on caliper, height, fresh weight, and percent and amound of plantable stock. The highest number of good-quality trees was produced at a density of 12.5 trees per square foot.

Effect of capping agents: Structural, optical and biological properties of ZnO nanoparticles

NASA Astrophysics Data System (ADS)

Javed, Rabia; Usman, Muhammad; Tabassum, Saira; Zia, Muhammad

2016-11-01

Different biological activities of capped and uncapped ZnO nanoparticles were investigated, and the effects of potential capping agents on these biological activities were studied. ZnO nanoparticles were synthesized and capped by polyethylene glycol (PEG) and polyvinyl pyrrolidone (PVP) using a simple chemical method of co-precipitation. Characterization by X-ray diffraction (XRD), Fourier transform Infrared spectroscopy (FTIR) and UV-vis spectroscopy confirmed the crystallinity, size, functional group, and band gap of synthesized nanoparticles. Reduction in size occurred from 34 nm to 26 nm due to surfactant. Results of all biological activities indicated significantly higher values in capped as compared to uncapped nanoparticles. Antibacterial activity against Staphylococcus aureus (ATCC 6538), Bacillus subtilis (ATCC 6633), Escherichia coli (ATCC15224), and Acetobacter was obtained. This activity was more prominent against Gram-positive bacteria, and ZnO-PVP nanoparticles elucidated highest antibacterial activity (zone of inhibition 17 mm) against Gram-positive, Bacillus subtilis species. Antioxidant activities including total flavonoid content, total phenolic content, total antioxidant capacity, total reducing power and %age inhibition of DPPH, and antidiabetic activity against α-amylase enzyme found to be exhibited highest by ZnO-PEG nanoparticles.

Effect of pH on particles size and gas sensing properties of In{sub 2}O{sub 3} nanoparticles

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

Anand, Kanica, E-mail: kanica.anand@yahoo.com; Thangaraj, Rengasamy; Singh, Ravi Chand

In this work, indium oxide (In{sub 2}O{sub 3}) nanoparticles have been synthesized by co-precipitation method and the effect of pH on the structural and sensor response values of In{sub 2}O{sub 3} nanoparticles has been reported. X-ray diffraction pattern (XRD) revealed the formation of cubic phase In{sub 2}O{sub 3} nanoparticles. FESEM results indicate the formation of nearly spherical shape In{sub 2}O{sub 3} nanoparticles. The band gap energy value changed with change in pH value and found to have highest value at pH 9. Indium oxide nanoparticles thus prepared were deposited as thick films on alumina substrates to act as gas sensorsmore » and their sensing response to ethanol vapors and LPG at 50 ppm was investigated at different operating temperatures. It has been observed that all sensors exhibited optimum response at 300°C towards ethanol and at 400°C towards LPG. In{sub 2}O{sub 3} nanoparticles prepared at pH 9, being smallest in size as compared to other, exhibit highest sensor response (SR).« less

Stacking fault-mediated ultrastrong nanocrystalline Ti thin films

NASA Astrophysics Data System (ADS)

Wu, K.; Zhang, J. Y.; Li, G.; Wang, Y. Q.; Cui, J. C.; Liu, G.; Sun, J.

2017-11-01

In this work, we prepared nanocrystalline (NC) Ti thin films with abundant stacking faults (SFs), which were created via partial dislocations emitted from grain boundaries and which were insensitive to grain sizes. By employing the nanoindentation test, we investigated the effects of SFs and grain sizes on the strength of NC Ti films at room temperature. The high density of SFs significantly strengthens NC Ti films, via dislocation-SF interactions associated with the reported highest Hall-Petch slope of ˜20 GPa nm1/2, to an ultrahigh strength of ˜4.4 GPa, approaching ˜50% of its ideal strength.

Impact of magnetic field parameters and iron oxide nanoparticle properties on heat generation for use in magnetic hyperthermia

PubMed Central

Shah, Rhythm R.; Davis, Todd P.; Glover, Amanda L.; Nikles, David E.; Brazel, Christopher S.

2015-01-01

Heating of nanoparticles (NPs) using an AC magnetic field depends on several factors, and optimization of these parameters can improve the efficiency of heat generation for effective cancer therapy while administering a low NP treatment dose. This study investigated magnetic field strength and frequency, NP size, NP concentration, and solution viscosity as important parameters that impact the heating efficiency of iron oxide NPs with magnetite (Fe3O4) and maghemite (γ-Fe2O3) crystal structures. Heating efficiencies were determined for each experimental setting, with specific absorption rates (SARs) ranging from 3.7 to 325.9 W/g Fe. Magnetic heating was conducted on iron oxide NPs synthesized in our laboratories (with average core sizes of 8, 11, 13, and 18 nm), as well as commercially-available iron oxides (with average core sizes of 8, 9, and 16 nm). The experimental magnetic coil system made it possible to isolate the effect of magnetic field parameters and independently study the effect on heat generation. The highest SAR values were found for the 18 nm synthesized particles and the maghemite nanopowder. Magnetic field strengths were applied in the range of 15.1 to 47.7 kA/m, with field frequencies ranging from 123 to 430 kHz. The best heating was observed for the highest field strengths and frequencies tested, with results following trends predicted by the Rosensweig equation. An increase in solution viscosity led to lower heating rates in nanoparticle solutions, which can have significant implications for the application of magnetic fluid hyperthermia in vivo. PMID:25960599

Impact of magnetic field parameters and iron oxide nanoparticle properties on heat generation for use in magnetic hyperthermia

NASA Astrophysics Data System (ADS)

Shah, Rhythm R.; Davis, Todd P.; Glover, Amanda L.; Nikles, David E.; Brazel, Christopher S.

2015-08-01

Heating of nanoparticles (NPs) using an AC magnetic field depends on several factors, and optimization of these parameters can improve the efficiency of heat generation for effective cancer therapy while administering a low NP treatment dose. This study investigated magnetic field strength and frequency, NP size, NP concentration, and solution viscosity as important parameters that impact the heating efficiency of iron oxide NPs with magnetite (Fe3O4) and maghemite (γ-Fe2O3) crystal structures. Heating efficiencies were determined for each experimental setting, with specific absorption rates (SARs) ranging from 3.7 to 325.9 W/g Fe. Magnetic heating was conducted on iron oxide NPs synthesized in our laboratories (with average core sizes of 8, 11, 13, and 18 nm), as well as commercially-available iron oxides (with average core sizes of 8, 9, and 16 nm). The experimental magnetic coil system made it possible to isolate the effect of magnetic field parameters and independently study the effect on heat generation. The highest SAR values were found for the 18 nm synthesized particles and the maghemite nanopowder. Magnetic field strengths were applied in the range of 15.1-47.7 kA/m, with field frequencies ranging from 123 to 430 kHz. The best heating was observed for the highest field strengths and frequencies tested, with results following trends predicted by the Rosensweig equation. An increase in solution viscosity led to lower heating rates in nanoparticle solutions, which can have significant implications for the application of magnetic fluid hyperthermia in vivo.

Effect of liquid nitrogen pre-treatment on various types of wool waste fibres for biogas production.

PubMed

Kuzmanova, Elena; Zhelev, Nikolai; Akunna, Joseph C

2018-05-01

This study investigated the role of liquid nitrogen (LN 2 ) in increasing microbial accessibility of wool proteins for biogas production. It involves a mechanical size reduction of four different types of raw wool fibres, namely, Blackface, Bluefaced Leicester, Texel and Scotch Mule, in presence of liquid nitrogen, followed by the determination of the methane production potential of the pre-treated wool fibres. The highest methane yield, 157.3 cm 3 g -1 VS, was obtained from pre-treated Scotch mule wool fibre culture, and represented more than 80% increase when compared to the yield obtained from its raw equivalent culture. The increase in biogas yield was attributed to the effectiveness of LN 2 in enhancing particle size reduction and the consequent increase in wool solubility and bioavailability. Results also showed that LN 2 pre-treatment can enhance size reduction but has limited effect on the molecular structure. The study also showed that the biogas potential of waste wool fibres varies with the type and source of wool.

Effects of Systematic Variation in Size and Surface Coating of Silver Nanoparticles on Their In Vitro Toxicity to Macrophage RAW 264.7 Cells.

PubMed

Makama, Sunday; Kloet, Samantha K; Piella, Jordi; van den Berg, Hans; de Ruijter, Norbert C A; Puntes, Victor F; Rietjens, Ivonne M C M; van den Brink, Nico W

2018-03-01

In literature, varying and sometimes conflicting effects of physicochemical properties of nanoparticles (NPs) are reported on their uptake and effects in organisms. To address this, small- and medium-sized (20 and 50 nm) silver nanoparticles (AgNPs) with specified different surface coating/charges were synthesized and used to systematically assess effects of NP-properties on their uptake and effects in vitro. Silver nanoparticles were fully characterized for charge and size distribution in both water and test media. Macrophage cells (RAW 264.7) were exposed to these AgNPs at different concentrations (0-200 µg/ml). Uptake dynamics, cell viability, induction of tumor necrosis factor (TNF)-α, ATP production, and reactive oxygen species (ROS) generation were assessed. Microscopic imaging of living exposed cells showed rapid uptake and subcellular cytoplasmic accumulation of AgNPs. Exposure to the tested AgNPs resulted in reduced overall viability. Influence of both size and surface coating (charge) was demonstrated, with the 20-nm-sized AgNPs and bovine serum albumin (BSA)-coated (negatively charged) AgNPs being slightly more toxic. On specific mechanisms of toxicity (TNF-α and ROS production) however, the AgNPs differed to a larger extent. The highest induction of TNF-α was found in cells exposed to the negatively charged AgNP_BSA, both sizes (80× higher than control). Reactive oxygen species induction was only significant with the 20 nm positively charged AgNP_Chit.

The Effectiveness of Psychoeducational Interventions Focused on Sexuality in Cancer.

PubMed

Kim, Jung-Hee; Yang, Younghee; Hwang, Eun-Suk

2015-01-01

Although sexual health is a common concern for oncology patients, no practical guidelines to sexual intervention exist, perhaps because of a lack of systematic reviews or meta-analyses. The objectives of this study were to determine the effect size for psychoeducational intervention focused on sexuality and to compare effect sizes according to intervention outcomes and characteristic. We explored quantitative evidence for the effects of sexual intervention for cancer patients or partners by using the electronic databases. Among them, we considered 15 eligible articles. The meta-analysis provided 133 effect sizes from 15 primary studies. The analysis revealed significant improvements after intervention, with a random-effects standardized mean difference of 0.75. Psychoeducational interventions focused on sexuality after cancer diagnosis were effective for compliance (2.40), cognitive aspect (1.29), and psychological aspect (0.83). Individual-based interventions (0.85) were more effective in improving outcomes than group approach and group combined with individual intervention. With regard to intervention providers, registered nurse only (2.22) and team approach including the registered nurse (2.38) had the highest effect size. Face-to-face intervention combined with telephone or the Internet (1.04) demonstrated a higher effect size than face-to-face (0.62) and telephone (0.58) independently. We conducted an analysis of data from various subgroups of preexisting studies, obtained an overall estimate of the effectiveness of the intervention, and compared its effectiveness across variables that affect intervention outcomes. These results provide empirical data for evidence-based practice and inform the development of useful intervention programs through a comprehensive review and meta-analysis of the results.

Assessing the fate and effects of nano aluminum oxide in the terrestrial earthworm, Eisenia fetida.

PubMed

Coleman, Jessica G; Johnson, David R; Stanley, Jacob K; Bednar, Anthony J; Weiss, Charles A; Boyd, Robert E; Steevens, Jeffery A

2010-07-01

Nano-sized aluminum is currently being used by the military and commercial industries in many applications including coatings, thermites, and propellants. Due to the potential for wide dispersal in soil systems, we chose to investigate the fate and effects of nano-sized aluminum oxide (Al2O3), the oxidized form of nano aluminum, in a terrestrial organism. The toxicity and bioaccumulation potential of micron-sized (50-200 microm, nominal) and nano-sized (11 nm, nominal) Al2O3 was comparatively assessed through acute and subchronic bioassays using the terrestrial earthworm, Eisenia fetida. Subchronic (28-d) studies were performed exposing E. fetida to nano- and micron-sized Al2O3-spiked soils to assess the effects of long-term exposure. No mortality occurred in subchronic exposures, although reproduction decreased at >or=3,000 mg/kg nano-sized Al2O3 treatments, with higher aluminum body burdens observed at 100 and 300 mg/kg; no reproductive effects were observed in the micron-sized Al2O3 treatments. In addition to toxicity and bioaccumulation bioassays, an acute (48-h) behavioral bioassay was conducted utilizing a soil avoidance wheel in which E. fetida were given a choice of habitat between control, nano-, or micron-sized Al2O3 amended soils. In the soil avoidance bioassays, E. fetida exhibited avoidance behavior toward the highest concentrations of micron- and nano-sized Al2O3 (>5,000 mg/kg) relative to control soils. Results of the present study indicate that nano-sized Al2O3 may impact reproduction and behavior of E. fetida, although at high levels unlikely to be found in the environment. Copyright (c) 2010 SETAC.

Accuracy of various impression materials and methods for two implant systems: An effect size study.

PubMed

Schmidt, Alexander; Häussling, Teresa; Rehmann, Peter; Schaaf, Heidrun; Wöstmann, Bernd

2018-04-01

An accurate impression is required for implant treatment. The aim of this in-vitro study was to determine the effect size of the impression material/method, implant system and implant angulation on impression transfer precision. An upper jaw model with three BEGO and three Straumann implants (angulations 0°, 15°, 20°) in the left and right maxilla was used as a reference model. One polyether (Impregum Penta) and two polyvinyl siloxanes (Flexitime Monophase/Aquasil Ultra Monophase) were examined with two impression techniques (open and closed tray). A total of 60 impressions were made. A coordinate measurement machine was used to measure the target variables for 3D-shift, implant axis inclination and implant axis rotation. All the data were subjected to a four-way ANOVA. The effect size (partial eta-squared [η 2 P ]) was reported. The impression material had a significant influence on the 3D shift and the implant axis inclination deviation (p-values=.000), and both factors had very large effect sizes (3D-shift [η 2 P ]=.599; implant axis inclination [η 2 P ]=.298). Impressions made with polyvinyl siloxane exhibited the highest transfer precision. When the angulation of the implants was larger, more deviations occurred for the implant axis rotational deviation. The implant systems and impression methods showed partially significant variations (p-values=.001-.639) but only very small effect sizes (η 2 P =.001-.031). The impression material had the greatest effect size on accuracy in terms of the 3D shift and the implant axis inclination. For multiunit restorations with disparallel implants, polyvinyl siloxane materials should be considered. In addition, the effect size of a multivariate investigation should be reported. Copyright © 2017 Japan Prosthodontic Society. Published by Elsevier Ltd. All rights reserved.

Evaluation of Wear Resistance of Friction Materials Prepared by Granulation.

PubMed

Ma, Yunhai; Liu, Yucheng; Menon, Carlo; Tong, Jin

2015-10-21

The tribological properties of friction materials prepared by hot-pressing pellets of different sizes were experimentally investigated. Friction and wear tests of the specimens were performed and morphological analysis was carried out by investigating images acquired with both scanning electron and confocal laser microscopes. The highest friction coefficient of friction materials was obtained with pellets having 1-5 mm size. The lowest wear rate was obtained with pellets having 8-10 mm size. Specimens processed by mixing pellets of different sizes had the highest density and the lowest roughness and were the least expensive to fabricate. The results show that granulation generally enabled increasing the friction coefficient, decreasing the wear rate, and reducing the number of defects on the surface of friction materials.

The effect of colchicine on the size and bioactive compound of microalgae Spirulina platensis

NASA Astrophysics Data System (ADS)

Mahardika, A.; Mukti, A. T.; Arief, M.

2018-04-01

Polyploidy is one of the techniques used to increase the genetic variant and once used as a breeding method of plant. Colchicine is one of the chemical which apply to produce polyploid organisms, such as plant. This study aimed to determine the effect of colchicine on the size and phycocyanin content of Spirulinaplatensis.Research was used six treatments of colchicine concentration with three replications. S. platensis were immersed in the colchicine solution for 12 hours and were observed for 5 days culture. This research was showed that colchicine concentration of 0.1 % were resulted highest diameter of S. platensis(12.57 μm) while highphycocyanin content obtained by treatment of 0.025 % (0.091 mg/ml).

[Effects of different patterns surface mulching on soil properties and fruit trees growth and yield in an apple orchard].

PubMed

Zhang, Yi; Xie, Yong-Sheng; Hao, Ming-De; She, Xiao-Yan

2010-02-01

Taking a nine-year-old Fuji apple orchard in Loess Plateau as test object, this paper studied the effects of different patterns surface mulching (clean tillage, grass cover, plastic film mulch, straw mulch, and gravel mulch) on the soil properties and fruit trees growth and yield in this orchard. Grass cover induced the lowest differentiation of soil moisture profile, while gravel mulch induced the highest one. In treatment gravel mulch, the soil moisture content in apple trees root zone was the highest, which meant that there was more water available to apple trees. Surface mulching had significant effects on soil temperature, and generally resulted in a decrease in the maximum soil temperature. The exception was treatment plastic film mulch, in which, the soil temperature in summer exceeded the maximum allowable temperature for continuous root growth and physiological function. With the exception of treatment plastic film mulch, surface mulching increased the soil CO2 flux, which was the highest in treatment grass cover. Surface mulching also affected the proportion of various branch types and fruit yield. The proportion of medium-sized branches and fruit yield were the highest in treatment gravel mulch, while the fruit yield was the lowest in treatment grass cover. Factor analysis indicated that among the test surface mulching patterns, gravel mulch was most suitable for the apple orchards in gully region of Loess Plateau.

Effect of harvest time of red and white clover silage on chewing activity and particle size distribution in boli, rumen content and faeces in cows.

PubMed

Kornfelt, L F; Nørgaard, P; Weisbjerg, M R

2013-06-01

The study examined the effects of harvest time of red and white clover silage on eating and ruminating activity and particle size distribution in feed boli, rumen content and faeces in cows. The clover crops were harvested at two stages of growth and ensiled in bales. Red clover crops had 36% and 45% NDF in dry matter (DM) at early (ER) and late (LR) harvest, respectively, and the white clover crops had 19% and 29% NDF in DM at the early (EW) and late (LW) harvest, respectively. The silages were fed restrictively (80% of ad libitum intake) twice daily to four rumen cannulated non-lactating Jersey cows (588 ± 52 kg) in a 4 × 4 Latin square design. Jaw movements (JM) were recorded for 96 h continuously. Swallowed boli, rumen mat, rumen fluid and faeces samples were collected, washed in nylon bags (0.01 mm pore size) and freeze-dried before dry sieving through 4.750, 2.360, 1.000, 0.500, 0.212 and 0.106 mm into seven fractions. The length (PL) and width (PW) values of rumen and faeces particles within each fraction were measured by use of image analysis. The eating activity (min/kg DM intake; P < 0.05) was higher in LR compared with the other treatments. The eating activity (min/kg NDF intake; P < 0.05) was affected by clover type with highest values for white clover silage. The mean ruminating time (min/kg DM), daily ruminating cycles (P < 0.001) and JM during ruminating (P < 0.05) were affected by treatment with increasing values at later harvest time. The proportion of washed particle DM of total DM in boli (P < 0.001), rumen mat (P < 0.001), rumen fluid (P < 0.01) and faeces was (P < 0.001) highest by feeding LR. There were identified two peaks (modes 1 and 2) on the probability density distribution (PDF) of PW values of rumen mat and faeces, but only one peak (mode 1) for PL values. There was no difference in the mean and mode 1 PW and PL value in rumen mat between the four treatments. The mean PL, mode PL, mode 2 PW and mean PW in faeces were highest for LR (P < 0.05). The mean particle size in boli measured by sieving was higher at white clover compared with red clover treatments (P < 0.001) and the highest value in faeces was found in LR (P < 0.01). The two peaks on PDF for width values of rumen mat and faeces particles are most likely related to the leaves and the stems/petioles. In conclusion, the mean total chewing activity per kg DM was lowest for the white clover silage and increased for both silages due to later harvest time. The mean particle size in boli was smallest for LR, whereas the mean PL and PW in faeces were highest for the LR.

High-purity silica reflecting heat shield development

NASA Technical Reports Server (NTRS)

Congdon, W. M.

1974-01-01

A high-purity, fused-silica reflecting heat shield for the thermal protection of outer-planet probes was developed. Factors that strongly influence the performance of a silica heat shield were studied. Silica-bonded silica configurations, each prepared by a different technique, were investigated and rated according to its relative merits. Slip-casting was selected as the preferred fabrication method because it produced good reflectivity and good strength, and is relatively easy to scale up for a full-size outer-planet probe. The slips were cast using a variety of different particle sizes: continuous particle-size slips; monodisperse particle-size slips; and blends of monodisperse particle-size slips were studied. In general, smaller particles gave the highest reflectance. The monodisperse slips as well as the blend slips gave a higher reflectance than the continuous particle-size slips. An upgraded and fused natural quartz was used to study the effects of microstructure on reflectance and as the baseline to ascertain the increase in reflectance obtained from using a higher-purity synthetic material.

A challenge for theranostics: is the optimal particle for therapy also optimal for diagnostics?

NASA Astrophysics Data System (ADS)

Dreifuss, Tamar; Betzer, Oshra; Shilo, Malka; Popovtzer, Aron; Motiei, Menachem; Popovtzer, Rachela

2015-09-01

Theranostics is defined as the combination of therapeutic and diagnostic capabilities in the same agent. Nanotechnology is emerging as an efficient platform for theranostics, since nanoparticle-based contrast agents are powerful tools for enhancing in vivo imaging, while therapeutic nanoparticles may overcome several limitations of conventional drug delivery systems. Theranostic nanoparticles have drawn particular interest in cancer treatment, as they offer significant advantages over both common imaging contrast agents and chemotherapeutic drugs. However, the development of platforms for theranostic applications raises critical questions; is the optimal particle for therapy also the optimal particle for diagnostics? Are the specific characteristics needed to optimize diagnostic imaging parallel to those required for treatment applications? This issue is examined in the present study, by investigating the effect of the gold nanoparticle (GNP) size on tumor uptake and tumor imaging. A series of anti-epidermal growth factor receptor conjugated GNPs of different sizes (diameter range: 20-120 nm) was synthesized, and then their uptake by human squamous cell carcinoma head and neck cancer cells, in vitro and in vivo, as well as their tumor visualization capabilities were evaluated using CT. The results showed that the size of the nanoparticle plays an instrumental role in determining its potential activity in vivo. Interestingly, we found that although the highest tumor uptake was obtained with 20 nm C225-GNPs, the highest contrast enhancement in the tumor was obtained with 50 nm C225-GNPs, thus leading to the conclusion that the optimal particle size for drug delivery is not necessarily optimal for imaging. These findings stress the importance of the investigation and design of optimal nanoparticles for theranostic applications.Theranostics is defined as the combination of therapeutic and diagnostic capabilities in the same agent. Nanotechnology is emerging as an efficient platform for theranostics, since nanoparticle-based contrast agents are powerful tools for enhancing in vivo imaging, while therapeutic nanoparticles may overcome several limitations of conventional drug delivery systems. Theranostic nanoparticles have drawn particular interest in cancer treatment, as they offer significant advantages over both common imaging contrast agents and chemotherapeutic drugs. However, the development of platforms for theranostic applications raises critical questions; is the optimal particle for therapy also the optimal particle for diagnostics? Are the specific characteristics needed to optimize diagnostic imaging parallel to those required for treatment applications? This issue is examined in the present study, by investigating the effect of the gold nanoparticle (GNP) size on tumor uptake and tumor imaging. A series of anti-epidermal growth factor receptor conjugated GNPs of different sizes (diameter range: 20-120 nm) was synthesized, and then their uptake by human squamous cell carcinoma head and neck cancer cells, in vitro and in vivo, as well as their tumor visualization capabilities were evaluated using CT. The results showed that the size of the nanoparticle plays an instrumental role in determining its potential activity in vivo. Interestingly, we found that although the highest tumor uptake was obtained with 20 nm C225-GNPs, the highest contrast enhancement in the tumor was obtained with 50 nm C225-GNPs, thus leading to the conclusion that the optimal particle size for drug delivery is not necessarily optimal for imaging. These findings stress the importance of the investigation and design of optimal nanoparticles for theranostic applications. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr03119b

The Impact of Fish Predation and Cyanobacteria on Zooplankton Size Structure in 96 Subtropical Lakes

PubMed Central

Zhang, Jing; Xie, Ping; Tao, Min; Guo, Longgen; Chen, Jun; Li, Li; XueZhen Zhang; Zhang, Lu

2013-01-01

Zooplankton are relatively small in size in the subtropical regions. This characteristic has been attributed to intense predation pressure, high nutrient loading and cyanobacterial biomass. To provide further information on the effect of predation and cyanobacteria on zooplankton size structure, we analyzed data from 96 shallow aquaculture lakes along the Yangtze River. Contrary to former studies, both principal components analysis and multiple regression analysis showed that the mean zooplankton size was positively related to fish yield. The studied lakes were grouped into three types, namely, natural fishing lakes with low nutrient loading (Type1), planktivorous fish-dominated lakes (Type 2), and eutrophic lakes with high cyanobacterial biomass (Type 3). A marked difference in zooplankton size structure was found among these groups. The greatest mean zooplankton size was observed in Type 2 lakes, but zooplankton density was the lowest. Zooplankton abundance was highest in Type 3 lakes and increased with increasing cyanobacterial biomass. Zooplankton mean size was negatively correlated with cyanobacterial biomass. No obvious trends were found in Type 1 lakes. These results were reflected by the normalized biomass size spectrum, which showed a unimodal shape with a peak at medium sizes in Type 2 lakes and a peak at small sizes in Type 3 lakes. These results indicated a relative increase in medium-sized and small-sized species in Types 2 and 3 lakes, respectively. Our results suggested that fish predation might have a negative effect on zooplankton abundance but a positive effect on zooplankton size structure. High cyanobacterial biomass most likely caused a decline in the zooplankton size and encouraged the proliferation of small zooplankton. We suggest that both planktivorous fish and cyanobacteria have substantial effects on the shaping of zooplankton community, particularly in the lakes in the eastern plain along the Yangtze River where aquaculture is widespread and nutrient loading is high. PMID:24124552

The impact of fish predation and cyanobacteria on zooplankton size structure in 96 subtropical lakes.

PubMed

Zhang, Jing; Xie, Ping; Tao, Min; Guo, Longgen; Chen, Jun; Li, Li; Xuezhen Zhang; Zhang, Lu

2013-01-01

Zooplankton are relatively small in size in the subtropical regions. This characteristic has been attributed to intense predation pressure, high nutrient loading and cyanobacterial biomass. To provide further information on the effect of predation and cyanobacteria on zooplankton size structure, we analyzed data from 96 shallow aquaculture lakes along the Yangtze River. Contrary to former studies, both principal components analysis and multiple regression analysis showed that the mean zooplankton size was positively related to fish yield. The studied lakes were grouped into three types, namely, natural fishing lakes with low nutrient loading (Type1), planktivorous fish-dominated lakes (Type 2), and eutrophic lakes with high cyanobacterial biomass (Type 3). A marked difference in zooplankton size structure was found among these groups. The greatest mean zooplankton size was observed in Type 2 lakes, but zooplankton density was the lowest. Zooplankton abundance was highest in Type 3 lakes and increased with increasing cyanobacterial biomass. Zooplankton mean size was negatively correlated with cyanobacterial biomass. No obvious trends were found in Type 1 lakes. These results were reflected by the normalized biomass size spectrum, which showed a unimodal shape with a peak at medium sizes in Type 2 lakes and a peak at small sizes in Type 3 lakes. These results indicated a relative increase in medium-sized and small-sized species in Types 2 and 3 lakes, respectively. Our results suggested that fish predation might have a negative effect on zooplankton abundance but a positive effect on zooplankton size structure. High cyanobacterial biomass most likely caused a decline in the zooplankton size and encouraged the proliferation of small zooplankton. We suggest that both planktivorous fish and cyanobacteria have substantial effects on the shaping of zooplankton community, particularly in the lakes in the eastern plain along the Yangtze River where aquaculture is widespread and nutrient loading is high.

The Chemistry and Bioaccumulation of Copper and Other Heavy Metals By Phytoplankton in the Water Column of San Diego Harbor and Its Relationship to Ecological Assessment and Water Quality

DTIC Science & Technology

1999-09-30

A suite of PCB congeners were added to these systems and the kinetics of partitioning between bacterial and protist size classes was measured to...Interestingly, the protists that produced the highest surfactant levels were the least effective at dissolving refractory iron oxide phases (from the

Assessment of β-carotene content, cell physiology and morphology of the yellow yeast Rhodotorula glutinis mutant 400A15 using flow cytometry.

PubMed

Cutzu, Raffaela; Clemente, Ana; Reis, Alberto; Nobre, Beatriz; Mannazzu, Ilaria; Roseiro, José; Lopes da Silva, Teresa

2013-08-01

Flow cytometry was used to assess β-carotene content, cell membrane permeability, cell size and granularity in Rhodotorula glutinis mutant 400A15 grown under different oxygen transfer coefficients (k L a) and carbon to nitrogen ratios (C/N). A Doehlert distribution was used in order to select the best conditions that induced the highest carotenoids production. The highest β-carotene content (0.79 mg g(-1) DCW) at the lowest k L a and C/N (5 × 10(-3) s(-1) and 11.3 respectively). Under these conditions, the biomass concentration attained 18.60 g L(-1). The highest ratio of cells with permeabilised membranes (2.6 %), and the highest cell size and granularity were also obtained under these conditions. It was observed that C/N showed a stronger influence than the k L a on the measured cell parameters.

Facile high-yield synthesis of polyaniline nanosticks with intrinsic stability and electrical conductivity.

PubMed

Li, Xin-Gui; Li, Ang; Huang, Mei-Rong

2008-01-01

Chemical oxidative polymerization at 15 degrees C was used for the simple and productive synthesis of polyaniline (PAN) nanosticks. The effect of polymerization media on the yield, size, stability, and electrical conductivity of the PAN nanosticks was studied by changing the concentration and nature of the acid medium and oxidant and by introducing organic solvent. Molecular and supramolecular structure, size, and size distribution of the PAN nanosticks were characterized by UV/Vis and IR spectroscopy, X-ray diffraction, laser particle-size analysis, and transmission electron microscopy. Introduction of organic solvent is advantageous for enhancing the yield of PAN nanosticks but disadvantageous for formation of PAN nanosticks with small size and high conductivity. The concentration and nature of the acid medium have a major influence on the polymerization yield and conductivity of the nanosized PAN. The average diameter and length of PAN nanosticks produced with 2 M HNO(3) and 0.5 M H(2)SO(4) as acid media are about 40 and 300 nm, respectively. The PAN nanosticks obtained in an optimal medium (i.e., 2 M HNO(3)) exhibit the highest conductivity of 2.23 S cm(-1) and the highest yield of 80.7 %. A mechanism of formation of nanosticks instead of nanoparticles is proposed. Nanocomposite films of the PAN nanosticks with poly(vinyl alcohol) show a low percolation threshold of 0.2 wt %, at which the film retains almost the same transparency and strength as pure poly(vinyl alcohol) but 262 000 times the conductivity of pure poly(vinyl alcohol) film. The present synthesis of PAN nanosticks requires no external stabilizer and provides a facile and direct route for fabrication of PAN nanosticks with high yield, controllable size, intrinsic self-stability, strong redispersibility, high purity, and optimizable conductivity.

Sensitivity studies of beam directionality, beam size, and neutron spectrum for a fission converter-based epithermal neutron beam for boron neutron capture therapy.

PubMed

Sakamoto, S; Kiger, W S; Harling, O K

1999-09-01

Sensitivity studies of epithermal neutron beam performance in boron neutron capture therapy are presented for realistic neutron beams with varying filter/moderator and collimator/delimiter designs to examine the relative importance of neutron beam spectrum, directionality, and size. Figures of merit for in-air and in-phantom beam performance are calculated via the Monte Carlo technique for different well-optimized designs of a fission converter-based epithermal neutron beam with head phantoms as the irradiation target. It is shown that increasing J/phi, a measure of beam directionality, does not always lead to corresponding monotonic improvements in beam performance. Due to the relatively low significance, for most configurations, of its effect on in-phantom performance and the large intensity losses required to produce beams with very high J/phi, beam directionality should not be considered an important figure of merit in epithermal neutron beam design except in terms of its consequences on patient positioning and collateral dose. Hardening the epithermal beam spectrum, while maintaining the specific fast neutron dose well below the inherent hydrogen capture dose, improves beam penetration and advantage depth and, as a desirable by-product, significantly increases beam intensity. Beam figures of merit are shown to be strongly dependent on beam size relative to target size. Beam designs with J/phi approximately 0.65-0.7, specific fast neutron doses of 2-2.6x10(-13) Gy cm2/n and beam sizes equal to or larger than the size of the head target produced the deepest useful penetration, highest therapeutic ratios, and highest intensities.

Quinoa starch granules as stabilizing particles for production of Pickering emulsions.

PubMed

Rayner, Marilyn; Sjöö, Malin; Timgren, Anna; Dejmek, Petr

2012-01-01

Intact starch granules isolated from quinoa (Chenopodium quinoa Willd.) were used to stabilize emulsion drops in so-called Pickering emulsions. Miglyol 812 was used as dispersed phase and a phosphate buffer (pH7) with different salt (NaCl) concentrations was used as the continuous phase. The starch granules were hydrophobically modified to different degrees by octenyl succinic anhydride (OSA) or by dry heat treatment at 120 degrees C in order to study the effect on the resulting emulsion drop size. The degree of OSA-modification had a low to moderate impact on drop size. The highest level of modification (4.66%) showed the largest mean drop size, and lowest amount of free starch, which could be an effect of a higher degree of aggregation of the starch granules and, thereby, also the emulsion drops stabilized by them. The heat treated starch granules had a poor stabilizing ability and only the starch heated for the longest time (150 min at 120 degrees C) had a better emulsifying capacity than the un-modified native starch granules. The effect of salt concentration was rather limited. However, an increased concentration of salt slightly increased the mean drop size and the elastic modulus.

Augmenting the post-transplantation growth and survivorship of juvenile scleractinian corals via nutritional enhancement.

PubMed

Toh, Tai Chong; Ng, Chin Soon Lionel; Peh, Jia Wei Kassler; Toh, Kok Ben; Chou, Loke Ming

2014-01-01

Size-dependent mortality influences the recolonization success of juvenile corals transplanted for reef restoration and assisting juvenile corals attain a refuge size would thus improve post-transplantation survivorship. To explore colony size augmentation strategies, recruits of the scleractinian coral Pocillopora damicornis were fed with live Artemia salina nauplii twice a week for 24 weeks in an ex situ coral nursery. Fed recruits grew significantly faster than unfed ones, with corals in the 3600, 1800, 600 and 0 (control) nauplii/L groups exhibiting volumetric growth rates of 10.65 ± 1.46, 4.69 ± 0.9, 3.64 ± 0.55 and 1.18 ± 0.37 mm3/week, respectively. Corals supplied with the highest density of nauplii increased their ecological volume by more than 74 times their initial size, achieving a mean final volume of 248.38 ± 33.44 mm3. The benefits of feeding were apparent even after transplantation to the reef. The corals in the 3600, 1800, 600 and 0 nauplii/L groups grew to final sizes of 4875 ± 260 mm3, 2036 ± 627 mm3, 1066 ± 70 mm3 and 512 ± 116 mm3, respectively. The fed corals had significantly higher survival rates than the unfed ones after transplantation (63%, 59%, 56% and 38% for the 3600, 1800, 600 and 0 nauplii/L treatments respectively). Additionally, cost-effectiveness analysis revealed that the costs per unit volumetric growth were drastically reduced with increasing feed densities. Corals fed with the highest density of nauplii were the most cost-effective (US$0.02/mm3), and were more than 12 times cheaper than the controls. This study demonstrated that nutrition enhancement can augment coral growth and post-transplantation survival, and is a biologically and economically viable option that can be used to supplement existing coral mariculture procedures and enhance reef restoration outcomes.

On the competition among aerosol number, size and composition in predicting CCN variability: a multi-annual field study in an urbanized desert.

PubMed

Crosbie, E; Youn, J-S; Balch, B; Wonaschütz, A; Shingler, T; Wang, Z; Conant, W C; Betterton, E A; Sorooshian, A

2015-02-10

A 2-year data set of measured CCN (cloud condensation nuclei) concentrations at 0.2 % supersaturation is combined with aerosol size distribution and aerosol composition data to probe the effects of aerosol number concentrations, size distribution and composition on CCN patterns. Data were collected over a period of 2 years (2012-2014) in central Tucson, Arizona: a significant urban area surrounded by a sparsely populated desert. Average CCN concentrations are typically lowest in spring (233 cm -3 ), highest in winter (430 cm -3 ) and have a secondary peak during the North American monsoon season (July to September; 372 cm -3 ). There is significant variability outside of seasonal patterns, with extreme concentrations (1 and 99 % levels) ranging from 56 to 1945 cm -3 as measured during the winter, the season with highest variability. Modeled CCN concentrations based on fixed chemical composition achieve better closure in winter, with size and number alone able to predict 82% of the variance in CCN concentration. Changes in aerosol chemical composition are typically aligned with changes in size and aerosol number, such that hygroscopicity can be parameterized even though it is still variable. In summer, models based on fixed chemical composition explain at best only 41% (pre-monsoon) and 36% (monsoon) of the variance. This is attributed to the effects of secondary organic aerosol (SOA) production, the competition between new particle formation and condensational growth, the complex interaction of meteorology, regional and local emissions and multi-phase chemistry during the North American monsoon. Chemical composition is found to be an important factor for improving predictability in spring and on longer timescales in winter. Parameterized models typically exhibit improved predictive skill when there are strong relationships between CCN concentrations and the prevailing meteorology and dominant aerosol physicochemical processes, suggesting that similar findings could be possible in other locations with comparable climates and geography.

The effect of microstructure on the performance of Li-ion porous electrodes

NASA Astrophysics Data System (ADS)

Chung, Ding-Wen

By combining X-ray tomography data and computer-generated porous elec- trodes, the impact of microstructure on the energy and power density of lithium-ion batteries is analyzed. Specifically, for commercial LiMn2O4 electrodes, results indi- cate that a broad particle size distribution of active material delivers up to two times higher energy density than monodisperse-sized particles for low discharge rates, and a monodisperse particle size distribution delivers the highest energy and power density for high discharge rates. The limits of traditionally used microstructural properties such as tortuosity, reactive area density, particle surface roughness, morphological anisotropy were tested against degree of particle size polydispersity, thus enabling the identification of improved porous architectures. The effects of critical battery processing parameters, such as layer compaction and carbon black, were also rationalized in the context of electrode performance. While a monodisperse particle size distribution exhibits the lowest possible tortuosity and three times higher surface area per unit volume with respect to an electrode conformed of a polydisperse particle size distribution, a comparable performance can be achieved by polydisperse particle size distributions with degrees of polydispersity less than 0.2 of particle size standard deviation. The use of non-spherical particles raises the tortuosity by as much as three hundred percent, which considerably lowers the power performance. However, favorably aligned particles can maximize power performance, particularly for high discharge rate applications.

Influence of particle size on water absorption capacity and mechanical properties of polyethylene-wood flour composites

NASA Astrophysics Data System (ADS)

Zykova, A. K.; Pantyukhov, P. V.; Kolesnikova, N. N.; Popov, A. A.; Olkhov, A. A.

2015-10-01

Biocomposites based on low density polyethylene (LDPE) and birch wood flour (WF) were investigated. The mechanical properties and water absorption capacity were examined depending on the particle size of a filler in biocomposites. The aim of the paper is the investigation of composite properties depending on the filler particle size. The filler particle sizes were 0-80 µm, 80-140 µm, 140-200 µm, and 0-200 µm. The tensile strength of composite samples varied within the range 5.7-8.2 MPa. Elongation at break of composites varied within the range 5.1-7.5%. Highest mechanical properties were found in composites with the lowest filler fraction. Highest water absorption was observed in composition with a complex fraction of the filler. The influence of the filler particle size on composite properties was shown. It was found that an increase of the filler particle size decreases mechanical parameters and increases water absorption.

Effect of the CTAB concentration on the upconversion emission of ZrO 2:Er 3+ nanocrystals

NASA Astrophysics Data System (ADS)

López-Luke, T.; De la Rosa, E.; Sólis, D.; Salas, P.; Angeles-Chavez, C.; Montoya, A.; Díaz-Torres, L. A.; Bribiesca, S.

2006-10-01

Upconversion emission of ZrO 2:Er 3+ (0.2 mol%) nanophosphor were studied as function of surfactant concentration after excitation at 968 nm. The strong green emission was produced by the transition 2H 11/2 + 4S 3/2 → 4I 15/2 and was explained in terms of cooperative energy transfer between neighboring ions. The upconverted signal was enhanced but the fluorescence decay time was reduced as either the surfactant concentration increases or the annealing time reduces. Experimental results show that surfactant concentration controls the particle size and morphology while annealing time control the phase composition and crystallite size. The highest intensity was obtained for a sample composed of a mixture of tetragonal (33 wt.%) and monoclinic (67 wt.%) phase with crystallite size of 31 and 59 nm, respectively. This result suggests that tetragonal crystalline structure and small crystallite size are more favorable for the upconversion emission.

Effects of particle size and hydro-thermal treatment of feed on performance and stomach health in fattening pigs.

PubMed

Liermann, Wendy; Berk, Andreas; Böschen, Verena; Dänicke, Sven

2015-01-01

Effects of grinding and hydro-thermal treatment of feed on growth performance, slaughter traits, nutrient digestibility, stomach content and stomach health were examined by using 96 crossbred fattening pigs. Pigs were fed a grain-soybean meal-based diet processed by various technical treatments. Feeding groups differed in particle size after grinding (finely vs. coarsely ground feed) and hydro-thermal treatment (without hydro-thermal treatment, pelleting, expanding, expanding and pelleting). Fine grinding and hydro-thermal treatment showed significant improvements on the digestibility of crude nutrients and content of metabolisable energy. Hydro-thermal treatment influenced average daily gain (ADG) and average daily feed intake (DFI) significantly. Finely ground pelleted feed without expanding enhanced performances by increasing ADG and decreasing feed-to-gain ratio (FGR) of fattening pigs. Coarsely ground feed without hydro-thermal treatment resulted in the highest ADG and DFI, however also in the highest FGR. Expanded feed decreased DFI and ADG. Slaughter traits were not affected by treatments. Coarsely ground feed without hydro-thermal treatment had protective effects on the health of gastric pars nonglandularis, however, pelleting increased gastric lesions. Hydro-thermal treatment, especially expanding, resulted in clumping of stomach content which possibly induced satiety by slower ingesta passage rate and thus decreased feed intake. Pigs fed pelleted feed showed less pronounced development of clumps in stomach content compared with expanded feed.

Effect of particle size distribution on 3D packings of spherical particles

NASA Astrophysics Data System (ADS)

Taiebat, Mahdi; Mutabaruka, Patrick; Pellenq, Roland; Radjai, Farhang

2017-06-01

We use molecular dynamics simulations of frictionless spherical particles to investigate a class of polydisperse granular materials in which the particle size distribution is uniform in particle volumes. The particles are assembled in a box by uniaxial compaction under the action of a constant stress. Due to the absence of friction and the nature of size distribution, the generated packings have the highest packing fraction at a given size span, defined as the ratio α of the largest size to the smallest size. We find that, up to α = 5, the packing fraction is a nearly linear function of α. While the coordination number is nearly constant due to the isostatic nature of the packings, we show that the connectivity of the particles evolves with α. In particular, the proportion of particles with 4 contacts represents the largest proportion of particles mostly of small size. We argue that this particular class of particles occurs as a result of the high stability of local configurations in which a small particle is stuck by four larger particles.

Transport of biocolloids in water saturated columns packed with sand: Effect of grain size and pore water velocity

NASA Astrophysics Data System (ADS)

Syngouna, Vasiliki I.; Chrysikopoulos, Constantinos V.

2012-03-01

The main objective of this study was to evaluate the combined effects of grain size and pore water velocity on the transport in water saturated porous media of three waterborne fecal indicator organisms (Escherichia coli, MS2, and ΦX174) in laboratory-scale columns packed with clean quartz sand. Three different grain sizes and three pore water velocities were examined and the attachment behavior of Escherichia coli, MS2, and ΦX174 onto quartz sand was evaluated. The mass recoveries of the biocolloids examined were shown to be highest for Escherichia coli and lowest for MS2. However, no obvious relationships between mass recoveries and water velocity or grain size could be established from the experimental results. The observed mean dispersivity values for each sand grain size were smaller for bacteria than coliphages, but higher for MS2 than ΦX174. The single collector removal and collision efficiencies were quantified using the classical colloid filtration theory. Furthermore, theoretical collision efficiencies were estimated only for E. coli by the Interaction-Force-Boundary-Layer, and Maxwell approximations. Better agreement between the experimental and Maxwell theoretical collision efficiencies were observed.

Transport of biocolloids in water saturated columns packed with sand: Effect of grain size and pore water velocity

NASA Astrophysics Data System (ADS)

Syngouna, Vasiliki I.; Chrysikopoulos, Constantinos V.

2011-11-01

The main objective of this study was to evaluate the combined effects of grain size and pore water velocity on the transport in water saturated porous media of three waterborne fecal indicator organisms ( Escherichia coli, MS2, and ΦX174) in laboratory-scale columns packed with clean quartz sand. Three different grain sizes and three pore water velocities were examined and the attachment behavior of Escherichia coli, MS2, and ΦX174 onto quartz sand was evaluated. The mass recoveries of the biocolloids examined were shown to be highest for Escherichia coli and lowest for MS2. However, no obvious relationships between mass recoveries and water velocity or grain size could be established from the experimental results. The observed mean dispersivity values for each sand grain size were smaller for bacteria than coliphages, but higher for MS2 than ΦX174. The single collector removal and collision efficiencies were quantified using the classical colloid filtration theory. Furthermore, theoretical collision efficiencies were estimated only for E. coli by the Interaction-Force-Boundary-Layer, and Maxwell approximations. Better agreement between the experimental and Maxwell theoretical collision efficiencies were observed.

The effect of cuff presence and cuff inflation on airway pressure in a canine tracheostomy tube model.

PubMed

Wignall, Jamie R; Baines, Stephen J

2014-01-01

To evaluate the effect of cuff presence and cuff inflation on airway pressure in an inspiratory model of canine tracheostomy. Ex vivo experimental study. Cadaver tracheas from Beagle dogs were attached aborally to a vacuum. Airway pressure and flow rate was measured before and after placement of tracheostomy tubes. None. Adult uncuffed tubes and cuffed tracheostomy tubes (sizes 4, 6, 8, and 10) were placed within tracheas. Cuffs were investigated without inflation and at maximum cuff inflation. Airway pressure was measured at constant airflow rates at 30 and 60 L/min. At set flow rates, airway pressures of tracheostomy tubes were compared to the intact trachea. A size 4 uncuffed tracheostomy tube showed the lowest airway pressure and a size 4 cuffed trachestomy tube with inflation showed the highest airway pressures. For sizes 6, 8, and 10 tubes, the presence of a cuff with and without inflation significantly increased airway pressure. Inflation of a cuff always significantly increased airway pressure. Similar pressure is seen between sizes 4 and 6 uncuffed tubes. Cuffed tracheostomy tubes should not be used unless specifically indicated due to increased airway pressure. © Veterinary Emergency and Critical Care Society 2013.

Dissolution characteristics of sericite in chalcopyrite bioleaching and its effect on copper extraction

NASA Astrophysics Data System (ADS)

Dong, Ying-bo; Li, Hao; Lin, Hai; Zhang, Yuan

2017-04-01

The effects of sericite particle size, rotation speed, and leaching temperature on sericite dissolution and copper extraction in a chalcopyrite bioleaching system were examined. Finer particles, appropriate temperature and rotation speed for Acidithiobacillus ferrooxidans resulted in a higher Al3+ dissolution concentration. The Al3+ dissolution concentration reached its highest concentration of 38.66 mg/L after 48-d leaching when the sericite particle size, temperature, and rotation speed were -43 μm, 30°C, and 160 r/min, respectively. Meanwhile, the sericite particle size, rotation speed, and temperature can affect copper extraction. The copper extraction rate is higher when the sericite particle size is finer. An appropriately high temperature is favorable for copper leaching. The dissolution of sericite fitted the shrinking core model, 1-(2/3) α-(1- α)2/3 = k 1 t, which indicates that internal diffusion is the decision step controlling the overall reaction rate in the leaching process. Scanning electron microscopy analysis showed small precipitates covered on the surface of sericite after leaching, which increased the diffusion resistance of the leaching solution and dissolved ions.

Procalcitonin for the early diagnosis of sepsis in burn patients: A retrospective study.

PubMed

Cabral, Luís; Afreixo, Vera; Santos, Filipe; Almeida, Luís; Paiva, José Artur

2017-11-01

The gold standard for sepsis diagnosis in burn patient still relies on microbiological cultures, which take 48-72h to provide results, delaying the start of antimicrobial therapy. Thus, biomarkers allowing an earlier sepsis diagnosis in burn patients are needed. This retrospective observational study included 150 burn patients with total burned surface area ≥15%. Clinical diagnosis of sepsis among these patients was done according to the American Burn Association criteria. Biomarker (procalcitonin, white blood cells and platelet countings, prothrombinemia, D-dimers, C-reactive protein, blood lactate and temperature) values were available for 48 patients without sepsis (2767 timepoints) and 102 patients with sepsis (652 timepoints). Quantitative variables were compared with Mann-Whitney tests and qualitative variables were compared with Pearson chi-square test. Effect size was measured by the probability of superiority. Receiver operating characteristic (ROC) curves evaluate capacity for sepsis diagnosis. Sensitivity, specificity, positive and negative predictive values were calculated for some cut-off values, including the best cut-off defined by the maximum of Youden index. Statistically significant differences between the groups of septic and non-septic patients, with medium to large effect size, were detected for all the biomarkers considered, except temperature. PCT was the biomarker with the largest AUC and effect size (AUC=0.71). Analysis of the PCT ROC curve showed that 0.5ng/mL cut-off presented highest sensitivity and lowest specificity, whereas 1.5ng/mL cut-off was associated with lowest sensitivity and highest specificity. Procalcitonin showed to be the best of the biomarkers studied for an early diagnosis of sepsis. Its use should be considered in antimicrobial stewardship programs in Burn Units. Copyright © 2017 Elsevier Ltd and ISBI. All rights reserved.

Food portion size area mediates energy effects on expected anxiety in anorexia nervosa.

PubMed

Herzog, Musya; Douglas, Christopher R; Kissileff, Harry R; Brunstrom, Jeffrey M; Halmi, Katherine Ann

2017-05-01

A study in which adolescent patients with anorexia nervosa (n = 24) rated their expected food-anxiety in response to images of portions of food (potatoes, rice pizza, and M&Ms) showed that lower energy-dense foods elicited higher expected anxiety per kilocalorie than higher energy-dense foods. However, the area of the portion sizes could be an unmeasured variable driving the anxiety response. To test the hypothesis that area mediates the effects of energy content on expected anxiety, the same images of portions were measured in area (cm 2 ), and standardized values of expected anxiety were regressed from standardized values of energy and area of portions. With regression of expected anxiety from portion size in area, M&Ms, which had the highest energy density of the four foods, elicited the highest expected anxiety slope (β = 1.75), which was significantly different from the expected anxiety slopes of the other three foods (β range = 0.67 - 0.96). Area was confirmed as a mediator of energy effects from loss of significance of the slopes when area was added to the regression of expected anxiety from energy x food. When expected anxiety was regressed from food, area, energy and area by energy interaction, area accounted for 5.7 times more variance than energy, and β for area (0.7) was significantly larger (by 0.52, SE = 0.15, t = 3.4, p = 0.0007) than β for energy (0.19). Area could be a learned cue for the energy content of food portions, and thus, for weight gain potential, which triggers anxiety in patients with anorexia nervosa. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

Effects of scarcity and excess of larval food on life history traits of Aedes aegypti (Diptera: Culicidae).

PubMed

Romeo Aznar, Victoria; Alem, Iris; De Majo, María Sol; Byttebier, Barbara; Solari, Hernán G; Fischer, Sylvia

2018-06-01

Few studies have assessed the effects of food scarcity or excess on the life history traits of Aedes aegypti (L.) (Diptera: Culicidae) independently from larval density. We assessed immature survival, development time, and adult size in relation to food availability. We reared cohorts of 30 Ae. aegypti larvae from newly hatched to adult emergence with different food availability. Food conditions were kept constant by transferring larvae each day to a new food solution. Immature development was completed by some individuals in all treatments. The shortest development time, the largest adults, and the highest survival were observed at intermediate food levels. The most important effects of food scarcity were an extension in development time, a decrease in the size of adults, and a slight decrease in survival, while the most important effects of food excess were an important decrease in survival and a slight decrease in the size of adults. The variability in development time and adult size within sex and treatment increased at decreasing food availability. The results suggest that although the studied population has adapted to a wide range of food availabilities, both scarcity and excess of food have important negative impacts on fitness. © 2018 The Society for Vector Ecology.

[Spectrum studies on titania photocatalysts].

PubMed

Su, W; Fu, X; Wei, K; Zhang, H; Lin, H; Wang, X; Li, D

2001-02-01

The nano-sized TiO2 photocatalysts were prepared by sol-gel method and characterized by FTIR spectroscopy, FT-Raman spectroscopy and diffuse reflectance spectroscopy(DRS). Photocatalytic degradation of oleic acid over the TiO2 catalysts was investigated. The result showed that calcination temperature has strong effect on crystal structure, energy band structure, optical adsorption and photocatalytic activity of the TiO2 catalysts. It was found that the TiO2 photocatalyst calcined at 400 degrees C has the best apparent optical adsorption, the biggest band edge position and the highest photoactivity. The effect of calcination temperature on photocatalytic activity of TiO2 catalysts has been ascribed to the changes in structure and optical property of catalyst such as crystal size, content of rutile, residual NO3-, and band-edge position of light adsorption.

Cloud Processed CCN Suppress Stratus Cloud Drizzle

NASA Astrophysics Data System (ADS)

Hudson, J. G.; Noble, S. R., Jr.

2017-12-01

Conversion of sulfur dioxide to sulfate within cloud droplets increases the sizes and decreases the critical supersaturation, Sc, of cloud residual particles that had nucleated the droplets. Since other particles remain at the same sizes and Sc a size and Sc gap is often observed. Hudson et al. (2015) showed higher cloud droplet concentrations (Nc) in stratus clouds associated with bimodal high-resolution CCN spectra from the DRI CCN spectrometer compared to clouds associated with unimodal CCN spectra (not cloud processed). Here we show that CCN spectral shape (bimodal or unimodal) affects all aspects of stratus cloud microphysics and drizzle. Panel A shows mean differential cloud droplet spectra that have been divided according to traditional slopes, k, of the 131 measured CCN spectra in the Marine Stratus/Stratocumulus Experiment (MASE) off the Central California coast. K is generally high within the supersaturation, S, range of stratus clouds (< 0.5%). Because cloud processing decreases Sc of some particles, it reduces k. Panel A shows higher concentrations of small cloud droplets apparently grown on lower k CCN than clouds grown on higher k CCN. At small droplet sizes the concentrations follow the k order of the legend, black, red, green, blue (lowest to highest k). Above 13 µm diameter the lines cross and the hierarchy reverses so that blue (highest k) has the highest concentrations followed by green, red and black (lowest k). This reversed hierarchy continues into the drizzle size range (panel B) where the most drizzle drops, Nd, are in clouds grown on the least cloud-processed CCN (blue), while clouds grown on the most processed CCN (black) have the lowest Nd. Suppression of stratus cloud drizzle by cloud processing is an additional 2nd indirect aerosol effect (IAE) that along with the enhancement of 1st IAE by higher Nc (panel A) are above and beyond original IAE. However, further similar analysis is needed in other cloud regimes to determine if MASE was typical. Hudson, J.G., S. Noble, and S. Tabor, 2015: J. Geophys. Res., Atmos., 120, 3436-3452, doi:10.1002/2014JD022669.

A Novel Approach of Using Ground CNTs as the Carbon Source to Fabricate Uniformly Distributed Nano-Sized TiCx/2009Al Composites.

PubMed

Wang, Lei; Qiu, Feng; Ouyang, Licheng; Wang, Huiyuan; Zha, Min; Shu, Shili; Zhao, Qinglong; Jiang, Qichuan

2015-12-17

Nano-sized TiC x /2009Al composites (with 5, 7, and 9 vol% TiC x ) were fabricated via the combustion synthesis of the 2009Al-Ti-CNTs system combined with vacuum hot pressing followed by hot extrusion. In the present study, CNTs were used as the carbon source to synthesize nano-sized TiC x particles. An attempt was made to correlate the effect of ground CNTs by milling and the distribution of synthesized nano-sized TiC x particles in 2009Al as well as the tensile properties of nano-sized TiC x /2009Al composites. Microstructure analysis showed that when ground CNTs were used, the synthesized nano-sized TiC x particles dispersed more uniformly in the 2009Al matrix. Moreover, when 2 h-milled CNTs were used, the 5, 7, and 9 vol% nano-sized TiC x /2009Al composites had the highest tensile properties, especially, the 9 vol% nano-sized TiC x /2009Al composites. The results offered a new approach to improve the distribution of in situ nano-sized TiC x particles and tensile properties of composites.

A Novel Approach of Using Ground CNTs as the Carbon Source to Fabricate Uniformly Distributed Nano-Sized TiCx/2009Al Composites

PubMed Central

Wang, Lei; Qiu, Feng; Ouyang, Licheng; Wang, Huiyuan; Zha, Min; Shu, Shili; Zhao, Qinglong; Jiang, Qichuan

2015-01-01

Nano-sized TiCx/2009Al composites (with 5, 7, and 9 vol% TiCx) were fabricated via the combustion synthesis of the 2009Al-Ti-CNTs system combined with vacuum hot pressing followed by hot extrusion. In the present study, CNTs were used as the carbon source to synthesize nano-sized TiCx particles. An attempt was made to correlate the effect of ground CNTs by milling and the distribution of synthesized nano-sized TiCx particles in 2009Al as well as the tensile properties of nano-sized TiCx/2009Al composites. Microstructure analysis showed that when ground CNTs were used, the synthesized nano-sized TiCx particles dispersed more uniformly in the 2009Al matrix. Moreover, when 2 h-milled CNTs were used, the 5, 7, and 9 vol% nano-sized TiCx/2009Al composites had the highest tensile properties, especially, the 9 vol% nano-sized TiCx/2009Al composites. The results offered a new approach to improve the distribution of in situ nano-sized TiCx particles and tensile properties of composites. PMID:28793749

Sediment toxicity and bioaccumulation of nano and micron-sized aluminum oxide.

PubMed

Stanley, Jacob K; Coleman, Jessica G; Weiss, Charles A; Steevens, Jeffery A

2010-02-01

Nano-aluminum oxide (Al(2)O(3)) is used commercially in coatings and abrasives. Nano-Al(2)O(3) can also be generated through the oxidation of nano-aluminum in military propellants and energetics. The purpose of the present study was to assess toxicity and bioaccumulation of nano-Al(2)O(3) to a variety of sediment organisms (Tubifex tubifex, Hyalella azteca, Lumbriculus variegatus, and Corbicula fluminea). The bioaccumulation and toxicity of nano-Al(2)O(3) was compared with that of micron-sized Al(2)O(3) to investigate potential size-related effects. Results of the present study show species-specific differences in relative bioaccumulation of nano and micron-sized Al(2)O(3). Significant toxic effects (survival and growth) were observed in H. azteca testing, but only at high concentrations unlikely to be found in the environment. Nano-Al(2)O(3) was found to be more toxic than micron-sized Al(2)O(3) to H. azteca survival in a 14-d study in which organisms were in direct contact with a thin layer of 625 or 2,500 mg of Al(2)O(3) dispersed on the surface of either sediment or sand. A significant growth effect was also observed for nano but not micron-sized Al(2)O(3) at the highest treatment level tested (100 g/kg Al(2)O(3)) in a 10-d H. azteca bioassay in which Al(2)O(3) was homogenized with sediment. However, differences in measured sediment Al concentrations (micron-sized = 55.1 [+/-0.6] g/kg Al; nano-sized = 66.2 [+/-0.6] g/kg Al) in the nano and micron-sized Al(2)O(3) preclude direct comparison of the toxicity of these two treatments based on particle size. Copyright 2009 SETAC.

Engineering Tenofovir Loaded Chitosan Nanoparticles

PubMed Central

Meng, Jianing; Sturgis, Timothy F.; Youan, Bi-Botti C.

2011-01-01

The objective of this study was to engineer a model anti-HIV microbicide (Tenofovir) loaded chitosan based nanoparticles (NPs). Box-Behnken design allowed to assess the influence of formulation variables on the size of NPs and drug encapsulation efficiency (EE%) that were analyzed by dynamic light scattering and UV spectroscopy, respectively. The effect of the NPs on vaginal epithelial cells and Lactobacillus crispatus viability and their mucoadhesion to porcine vaginal tissue were assessed by cytotoxicity assays and fluorimetry, respectively. In the optimal aqueous conditions, the EE% and NPs size was 5.83% and 207.97nm, respectively. With 50% (v/v) ethanol/water as alternative solvent, these two responses increased to 20% and 602 nm, respectively. Drug release from medium (281 nm) and large size (602 nm)-sized NPs fitted the Higuchi (r2=0.991) and first-order release (r2=0.999) models, respectively. These NPs were not cytotoxic to both the vaginal epithelial cell line and Lactobacillus for 48 hours. When the diameter of the NPs decreased from 900 nm to 188 nm, the mucoadhesion increased from 6% to 12%. However, the combinatorial effect of EE% × mucoadhesion for larger size NPs was the highest. Overall, large-size, microbicide loaded chitosan NPs appeared to be promising nanomedicines for the prevention of HIV transmission. PMID:21704704

Effects of plant size, temperature, and light intensity on flowering of Phalaenopsis hybrids in Mediterranean greenhouses.

PubMed

Paradiso, Roberta; De Pascale, Stefania

2014-01-01

Mediterranean greenhouses for cultivation of Phalaenopsis orchids reproduce the warm, humid, and shaded environment of tropical underbrush. Heating represents the highest production cost, due to the high thermal requirements and the long unproductive phase of juvenility, in which plants attain the critical size for flowering. Our researches aimed to investigate the effect of plant size, temperature, and light intensity, during the phase of flower induction, on flowering of modern genotypes selected for Mediterranean greenhouses. Three experiments were carried out to compare (i) plant size: reduced size versus size considered optimal for flowering (hybrids "Sogo Yukidian," "Chain Xen Diamond," and "Pinlong"); (ii) temperature: moderate reduction of temperature versus standard thermal regime (hybrid "Premium"); (iii) light intensity: supplemental lighting versus reference light intensity (hybrid "Premium"). The premature exposure of plants to the inductive treatment delayed the beginning of flowering and reduced the flower stem quality, in all the tested hybrids. In "Premium," the lower temperature did not affect flowering earliness and commercial quality of flower stems compared to the standard regime, whereas it promoted stem branching. In the same hybrid, supplemental lighting anticipated flowering and promoted the emission of the second stem and the stem branching, compared to the reference light regime.

Energy Content Estimation by Collegians for Portion Standardized Foods Frequently Consumed in Korea

PubMed Central

Kim, Jin; Lee, Hee Jung; Lee, Hyun Jung; Lee, Sun Ha; Yun, Jee-Young; Choi, Mi-Kyeong

2014-01-01

The purpose of this study is to estimate Korean collegians' knowledge of energy content in the standard portion size of foods frequently consumed in Korea and to investigate the differences in knowledge between gender groups. A total of 600 collegians participated in this study. Participants' knowledge was assessed based on their estimation on the energy content of 30 selected food items with their actual-size photo images. Standard portion size of food was based on 2010 Korean Dietary Reference Intakes, and the percentage of participants who accurately estimated (that is, within 20% of the true value) the energy content of the standard portion size was calculated for each food item. The food for which the most participants provided the accurate estimation was ramyun (instant noodles) (67.7%), followed by cooked rice (57.8%). The proportion of students who overestimated the energy content was highest for vegetables (68.8%) and beverages (68.1%). The proportion of students who underestimated the energy content was highest for grains and starches (42.0%) and fruits (37.1%). Female students were more likely to check energy content of foods that they consumed than male students. From these results, it was concluded that the knowledge on food energy content was poor among collegians, with some gender difference. Therefore, in the future, nutrition education programs should give greater attention to improving knowledge on calorie content and to helping them apply this knowledge in order to develop effective dietary plans. PMID:24527417

Energy content estimation by collegians for portion standardized foods frequently consumed in Korea.

PubMed

Kim, Jin; Lee, Hee Jung; Lee, Hyun Jung; Lee, Sun Ha; Yun, Jee-Young; Choi, Mi-Kyeong; Kim, Mi-Hyun

2014-01-01

The purpose of this study is to estimate Korean collegians' knowledge of energy content in the standard portion size of foods frequently consumed in Korea and to investigate the differences in knowledge between gender groups. A total of 600 collegians participated in this study. Participants' knowledge was assessed based on their estimation on the energy content of 30 selected food items with their actual-size photo images. Standard portion size of food was based on 2010 Korean Dietary Reference Intakes, and the percentage of participants who accurately estimated (that is, within 20% of the true value) the energy content of the standard portion size was calculated for each food item. The food for which the most participants provided the accurate estimation was ramyun (instant noodles) (67.7%), followed by cooked rice (57.8%). The proportion of students who overestimated the energy content was highest for vegetables (68.8%) and beverages (68.1%). The proportion of students who underestimated the energy content was highest for grains and starches (42.0%) and fruits (37.1%). Female students were more likely to check energy content of foods that they consumed than male students. From these results, it was concluded that the knowledge on food energy content was poor among collegians, with some gender difference. Therefore, in the future, nutrition education programs should give greater attention to improving knowledge on calorie content and to helping them apply this knowledge in order to develop effective dietary plans.

Solvent annealing of perovskite-induced crystal growth for photovoltaic-device efficiency enhancement

DOE PAGES

Xiao, Zhengguo; Dong, Qingfeng; Bi, Cheng; ...

2014-08-26

Solvent-annealing is found to be an effective method to increase the grain size and carrier diffusion lengths of trihalide perovskite materials. Thus, the carrier diffusion length of MAPbI 3 is increased to over 1 μm. The efficiency remains above 14.5% when the MAPbI 3 thickness changes from 250 nm to 1 μm, with the highest efficiency reaching 15.6%.

Traditional foods for health: screening of the antioxidant capacity and phenolic content of selected Black Sea area local foods.

PubMed

Danesi, Francesca; Pasini, Federica; Caboni, Maria Fiorenza; D'Antuono, Luigi Filippo; Bordoni, Alessandra

2013-11-01

The nutritional characteristics of the Black Sea area (BSA) traditional foods are almost unknown, and they could be interesting sources of antioxidant compounds. In this study, carried out within the BaSeFood project, the in vitro total antioxidant capacity (TAC) and phenolic content of 39 BSA traditional foods were determined using different assays. An ample range of TAC and phenolics content was detected in the examined foods that were ranked according to their scavenging activity expressed per weight unit and per serving size. Based on serving size, the highest TAC was in the order blueberries > nettle soup > sunflower seeds, and the fruits/fruit-based foods group was the one having the highest activity. Correlation analysis evidenced that the TAC is highly dependent on total phenolic content, while hydroxycinnamic acids and compounds having o-diphenolic structure did not show specific prominent effects. Finally, correlations between the two methods used for measuring the TAC suggest that they are both suitable in a wide range of foods. Our data represent the first contribution to further research on the health effects of BSA traditional foods. This could enhance the interest of consumers, with potential benefits to stakeholders at all levels of the production chain. © 2013 Society of Chemical Industry.

Effect of the degree of substitution of octenyl succinic anhydride-banana starch on emulsion stability.

PubMed

Bello-Pérez, Luis A; Bello-Flores, Christopher A; Nuñez-Santiago, María del Carmen; Coronel-Aguilera, Claudia P; Alvarez-Ramirez, J

2015-11-05

Banana starch was esterified with octenylsuccinic anhydride (OSA) at different degree substitution (DS) and used to stabilize emulsions. Morphology, emulsion stability, emulsification index, rheological properties and particle size distribution of the emulsions were tested. Emulsions dyed with Solvent Red 26 showed affinity for the oil phase. Backscattering light showed three regions in the emulsion where the emulsified region was present. Starch concentration had higher effect in the emulsification index (EI) than the DS used in the study because similar values were found with OSA-banana and native starches. However, OSA-banana presented greater stability of the emulsified region. Rheological tests in emulsions with OSA-banana showed G'>G" values and low dependence of G' with the frequency, indicating a dominant elastic response to shear. When emulsions were prepared under high-pressure conditions, the emulsions with OSA-banana starch with different DS showed a bimodal distribution of particle size. The emulsion with OSA-banana starch and the low DS showed similar mean droplet diameter than its native counterpart. In contrast, the highest DS led to the highest mean droplet diameter. It is concluded that OSA-banana starch with DS can be used to stabilize specific emulsion types. Copyright © 2015 Elsevier Ltd. All rights reserved.

Interspecific geographic range size-body size relationship and the diversification dynamics of Neotropical furnariid birds.

PubMed

Inostroza-Michael, Oscar; Hernández, Cristián E; Rodríguez-Serrano, Enrique; Avaria-Llautureo, Jorge; Rivadeneira, Marcelo M

2018-05-01

Among the earliest macroecological patterns documented, is the range and body size relationship, characterized by a minimum geographic range size imposed by the species' body size. This boundary for the geographic range size increases linearly with body size and has been proposed to have implications in lineages evolution and conservation. Nevertheless, the macroevolutionary processes involved in the origin of this boundary and its consequences on lineage diversification have been poorly explored. We evaluate the macroevolutionary consequences of the difference (hereafter the distance) between the observed and the minimum range sizes required by the species' body size, to untangle its role on the diversification of a Neotropical species-rich bird clade using trait-dependent diversification models. We show that speciation rate is a positive hump-shaped function of the distance to the lower boundary. The species with highest and lowest distances to minimum range size had lower speciation rates, while species close to medium distances values had the highest speciation rates. Further, our results suggest that the distance to the minimum range size is a macroevolutionary constraint that affects the diversification process responsible for the origin of this macroecological pattern in a more complex way than previously envisioned. © 2018 The Author(s). Evolution © 2018 The Society for the Study of Evolution.

Size-selective separation of polydisperse gold nanoparticles in supercritical ethane.

PubMed

Williams, Dylan P; Satherley, John

2009-04-09

The aim of this study was to use supercritical ethane to selectively disperse alkanethiol-stabilized gold nanoparticles of one size from a polydisperse sample in order to recover a monodisperse fraction of the nanoparticles. A disperse sample of metal nanoparticles with diameters in the range of 1-5 nm was prepared using established techniques then further purified by Soxhlet extraction. The purified sample was subjected to supercritical ethane at a temperature of 318 K in the pressure range 50-276 bar. Particles were characterized by UV-vis absorption spectroscopy, TEM, and MALDI-TOF mass spectroscopy. The results show that with increasing pressure the dispersibility of the nanoparticles increases, this effect is most pronounced for smaller nanoparticles. At the highest pressure investigated a sample of the particles was effectively stripped of all the smaller particles leaving a monodisperse sample. The relationship between dispersibility and supercritical fluid density for two different size samples of alkanethiol-stabilized gold nanoparticles was considered using the Chrastil chemical equilibrium model.

The countermovement jump to monitor neuromuscular status: A meta-analysis.

PubMed

Claudino, João Gustavo; Cronin, John; Mezêncio, Bruno; McMaster, Daniel Travis; McGuigan, Michael; Tricoli, Valmor; Amadio, Alberto Carlos; Serrão, Julio Cerca

2017-04-01

The primary objective of this meta-analysis was to compare countermovement jump (CMJ) performance in studies that reported the highest value as opposed to average value for the purposes of monitoring neuromuscular status (i.e., fatigue and supercompensation). The secondary aim was to determine the sensitivity of the dependent variables. Systematic review with meta-analysis. The meta-analysis was conducted on the highest or average of a number of CMJ variables. Multiple literature searches were undertaken in Pubmed, Scopus, and Web of Science to identify articles utilizing CMJ to monitor training status. Effect sizes (ES) with 95% confidence interval (95% CI) were calculated using the mean and standard deviation of the pre- and post-testing data. The coefficient of variation (CV) with 95% CI was also calculated to assess the level of instability of each variable. Heterogeneity was assessed using a random-effects model. 151 articles were included providing a total of 531 ESs for the meta-analyses; 85.4% of articles used highest CMJ height, 13.2% used average and 1.3% used both when reporting changes in CMJ performance. Based on the meta-analysis, average CMJ height was more sensitive than highest CMJ height in detecting CMJ fatigue and supercompensation. Furthermore, other CMJ variables such as peak power, mean power, peak velocity, peak force, mean impulse, and power were sensitive in tracking the supercompensation effects of training. The average CMJ height was more sensitive than highest CMJ height in monitoring neuromuscular status; however, further investigation is needed to determine the sensitivity of other CMJ performance variables. Copyright © 2016 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

Titania - Highest Resolution Voyager Picture

NASA Image and Video Library

1996-01-29

On Jan. 24, 1986, NASA Voyager 2 returned the highest-resolution picture of Titania, Uranus largest satellite. Abundant impact craters of many sizes pockmark the ancient surface; most prominent features are fault valleys that stretch across Titania. http://photojournal.jpl.nasa.gov/catalog/PIA00039

Anisotropy, size, and aspect ratio effects on micropillar compression of Al-SiC nanolaminate composites

DOE PAGES

Mayer, C. R.; Yang, L. W.; Singh, S. S.; ...

2016-05-20

Metal-ceramic nanolaminate composites show promise as high strength and toughness materials. Micropillar compression was used to characterize the mechanical behavior of AlSiC multilayers in different orientations including loading at 0°, 45° and 90° with respect to the direction of the layers. The 0° orientation showed the highest strength while the 45° orientation showed the lowest strength. Each orientation showed unique deformation behavior. Effects of pillar size and aspect ratio were also studied. Higher compressive strengths were observed in smaller pillars for all orientations. This effect was shown to be due to a lower probability of flaws using Weibull statistics. Additionally,more » changes in the aspect ratio was shown to have no significant effect on the behavior except an increase in the strain to failure in the 0° orientation. In conclusion, finite element analysis (FEA) was used to simulate and understand the effect of these parameters on the deformation behavior.« less

Effects of alcohol solvents on anatase TiO2 nanocrystals prepared by microwave-assisted solvothermal method

NASA Astrophysics Data System (ADS)

Wu, Yu-Chun; Tai, Yu-Chuen

2013-06-01

The effects of solvents on the anatase crystallite size prepared by sol-gel microwave-assisted solvothermal method were investigated in this study. Eight different alcohol solvents classified into two groups, i.e. primary and secondary/ternary alcohols, were used as reaction media and the effects of solvent properties, such as dielectric constant, boiling point, and internal pressure during the solvothermal process, on the crystallite size and shape were analyzed. According to the experimental results, selecting the solvent type allowed not only the alteration of the crystallite size but also the crystallite shape without the need of any additives. The boiling point of solvent was determined as the major factor influencing the crystallite size. Among the solvents with similar boiling points, the solvent with a higher carbon number produced the smaller crystallite size because of steric hindrance effect. In addition, the carboxyl groups dissociated from the alcohol solvent can play a role as a structural capping agent to retard the anatase crystal growth along the [001] direction and led to a rectangular crystallite shape with preferred development in {001} facets. On the other hand, the alcoholysis reaction was found easily occurred between the primary alcohol and isopropoxide that effectively limited the hydrolysis and condensation processes but also suppressed the structural capping effect. Therefore, the anatase crystals prepared in the primary alcohols became exceptionally small and showed spherical shape. Finally, the anatase crystals prepared using isopropanol demonstrated the highest photocatalytic activity due to its evident preferred crystallization in the {001} facets.

Effect of helmet liner systems and impact directions on severity of head injuries sustained in ballistic impacts: a finite element (FE) study.

PubMed

Tse, Kwong Ming; Tan, Long Bin; Yang, Bin; Tan, Vincent Beng Chye; Lee, Heow Pueh

2017-04-01

The current study aims to investigate the effectiveness of two different designs of helmet interior cushion, (Helmet 1: strap-netting; Helmet 2: Oregon Aero foam-padding), and the effect of the impact directions on the helmeted head during ballistic impact. Series of ballistic impact simulations (frontal, lateral, rear, and top) of a full-metal-jacketed bullet were performed on a validated finite element head model equipped with the two helmets, to assess the severity of head injuries sustained in ballistic impacts using both head kinematics and biomechanical metrics. Benchmarking with experimental ventricular and intracranial pressures showed that there is good agreement between the simulations and experiments. In terms of extracranial injuries, top impact had the highest skull stress, still without fracturing the skull. In regard to intracranial injuries, both the lateral and rear impacts generally gave the highest principal strains as well as highest shear strains, which exceed the injury thresholds. Off-cushion impacts were found to be at higher risk of intracranial injuries. The study also showed that the Oregon Aero foam pads helped to reduce impact forces. It also suggested that more padding inserts of smaller size may offer better protection. This provides some insights on future's helmet design against ballistic threats.

Gene family size conservation is a good indicator of evolutionary rates.

PubMed

Chen, Feng-Chi; Chen, Chiuan-Jung; Li, Wen-Hsiung; Chuang, Trees-Juen

2010-08-01

The evolution of duplicate genes has been a topic of broad interest. Here, we propose that the conservation of gene family size is a good indicator of the rate of sequence evolution and some other biological properties. By comparing the human-chimpanzee-macaque orthologous gene families with and without family size conservation, we demonstrate that genes with family size conservation evolve more slowly than those without family size conservation. Our results further demonstrate that both family expansion and contraction events may accelerate gene evolution, resulting in elevated evolutionary rates in the genes without family size conservation. In addition, we show that the duplicate genes with family size conservation evolve significantly more slowly than those without family size conservation. Interestingly, the median evolutionary rate of singletons falls in between those of the above two types of duplicate gene families. Our results thus suggest that the controversy on whether duplicate genes evolve more slowly than singletons can be resolved when family size conservation is taken into consideration. Furthermore, we also observe that duplicate genes with family size conservation have the highest level of gene expression/expression breadth, the highest proportion of essential genes, and the lowest gene compactness, followed by singletons and then by duplicate genes without family size conservation. Such a trend accords well with our observations of evolutionary rates. Our results thus point to the importance of family size conservation in the evolution of duplicate genes.

Reversed phase HPLC analysis of stability and microstructural effects on degradation kinetics of β-carotene encapsulated in freeze-dried maltodextrin-emulsion systems.

PubMed

Harnkarnsujarit, Nathdanai; Charoenrein, Sanguansri; Roos, Yrjö H

2012-09-26

Degradation of dispersed lipophilic compounds in hydrophilic solids depends upon matrix stability and lipid physicochemical properties. This study investigated effects of solid microstructure and size of lipid droplets on the stability of dispersed β-carotene in freeze-dried systems. Emulsions of β-carotene in sunflower oil were dispersed in maltodextrin systems (M040/DE6, M100/DE11, and M250/DE25.5) (8% w/w oil) and prefrozen at various freezing conditions prior to freeze-drying to control nucleation and subsequent pore size and structural collapse of freeze-dried solids. The particle size, physical state, and β-carotene contents of freeze-dried emulsions were measured during storage at various water activity (a(w)) using a laser particle size analyzer, differential scanning calorimeter, and high performance liquid chromatography (HPLC), respectively. The results showed that M040 stabilized emulsions in low temperature freezing exhibited lipid crystallization. Collapse of solids in storage at a(w) which plasticized systems to the rubbery state led to flow and increased the size of oil droplets. Degradation of β-carotene analyzed using a reversed-phase C(30) column followed first-order kinetics. Porosity of solids had a major effect on β-carotene stability; however, the highest stability was found in fully plasticized and collapsed solids.

Studies on hand-held visual communication device for the deaf and speech-impaired I. Visual display window size.

PubMed

Thurlow, W R

1980-01-01

Messages were presented which moved from right to left along an electronic alphabetic display which was varied in "window" size from 4 through 32 letter spaces. Deaf subjects signed the messages they perceived. Relatively few errors were made even at the highest rate of presentation, which corresponded to a typing rate of 60 words/min. It is concluded that many deaf persons can make effective use of a small visual display. A reduced cost is then possible for visual communication instruments for these people through reduced display size. Deaf subjects who can profit from a small display can be located by a sentence test administered by tape recorder which drives the display of the communication device by means of the standard code of the deaf teletype network.

Effects of annealing temperature on the H2-sensing properties of Pd-decorated WO3 nanorods

NASA Astrophysics Data System (ADS)

Lee, Sangmin; Lee, Woo Seok; Lee, Jae Kyung; Hyun, Soong Keun; Lee, Chongmu; Choi, Seungbok

2018-03-01

The temperature of the post-annealing treatment carried out after noble metal deposition onto semiconducting metal oxides (SMOs) must be carefully optimized to maximize the sensing performance of the metal-decorated SMO sensors. WO3 nanorods were synthesized by thermal evaporation of WO3 powders and decorated with Pd nanoparticles using a sol-gel method, followed by an annealing process. The effects of the annealing temperature on the hydrogen gas-sensing properties of the Pd-decorated WO3 nanorods were then examined; the optimal annealing temperature, leading to the highest response of the WO3 nanorod sensor to H2, was determined to be 600 °C. Post-annealing at 600 °C resulted in nanorods with the highest surface area-to-volume ratio, as well as in the optimal size and the largest number of deposited Pd nanoparticles, leading to the highest response and the shortest response/recovery times toward H2. The improved H2-sensing performance of the Pd-decorated WO3 nanorod sensor, compared to a sensor based on pristine WO3 nanorods, is attributed to the enhanced catalytic activity, increased surface area-to-volume ratio, and higher amounts of surface defects.

Placebo Response in Repetitive Transcranial Magnetic Stimulation Trials of Treatment of Auditory Hallucinations in Schizophrenia: A Meta-Analysis

PubMed Central

Dollfus, Sonia; Lecardeur, Laurent; Morello, Rémy; Etard, Olivier

2016-01-01

Several meta-analyses have assessed the response of patients with schizophrenia with auditory verbal hallucinations (AVH) to treatment with repetitive transcranial magnetic stimulation (rTMS); however, the placebo response has never been explored. Typically observed in a therapeutic trial, the placebo effect may have a major influence on the effectiveness of rTMS. The purpose of this meta-analysis is to evaluate the magnitude of the placebo effect observed in controlled studies of rTMS treatment of AVH, and to determine factors that can impact the magnitude of this placebo effect, such as study design considerations and the type of sham used. The study included twenty-one articles concerning 303 patients treated by sham rTMS. A meta-analytic method was applied to obtain a combined, weighted effect size, Hedges’s g. The mean weighted effect size of the placebo effect across these 21 studies was 0.29 (P < .001). Comparison of the parallel and crossover studies revealed distinct results for each study design; placebo has a significant effect size in the 13 parallel studies (g = 0.44, P < 10−4), but not in the 8 crossover studies (g = 0.06, P = .52). In meta-analysis of the 13 parallel studies, the 45° position coil showed the highest effect size. Our results demonstrate that placebo effect should be considered a major source of bias in the assessment of rTMS efficacy. These results fundamentally inform the design of further controlled studies, particularly with respect to studies of rTMS treatment in psychiatry. PMID:26089351

Effect of Prestraining of Recrystallization Temperature and Mechanical Properties of Commercial, Sintered, Wrought Molybdenum

NASA Technical Reports Server (NTRS)

Dike, Kenneth C; Long, Roger A

1953-01-01

Given three presumably identical lots of commercial, sintered, wrought molybdenum, the 1-hour recrystallization temperature of one lot remained above 2900 F by limiting the amount of effective restraining to 35 percent or less. Different recrystallization temperatures were obtained in various atmospheres, the highest in argon and the lowest in hydrogen. Metal thus fabricated and then stress-relieved possessed an ultimate tensile strength at room temperature within 10 percent of metal swaged 99 percent and also possessed equivalent ductility. At 1800 F, equivalent strength and ductility was obtained irrespective of the amount of swaging over the range of 10 to 99 percent. The amount of swaging greatly influenced the recrystallized grain size but the difference in grain size is not the major controlling factor which determines whether recrystallized molybdenum is ductile or brittle at room temperature.

Heat transfer performance characteristics of hybrid nanofluids as coolant in louvered fin automotive radiator

NASA Astrophysics Data System (ADS)

Sahoo, Rashmi R.; Sarkar, Jahar

2017-06-01

Present study deals with the enhancement of convective heat transfer performance of EG brine based various hybrid nanofluids i.e. Ag, Cu, SiC, CuO and TiO2 in 0-1% volume fraction of Al2O3 nanofluid, as coolants for louvered fin automobile radiator. The effects of nanoparticles combination and operating parameters on thermo physical properties, heat transfer, effectiveness, pumping power and performance index of hybrid nanofluids have been evaluated. Comparison of studied hybrid nanofluids based on radiator size and pumping power has been made as well. Among all studied hybrid nanofluids, 1% Ag hybrid nanofluid (0.5% Ag and 0.5% Al2O3) yields highest effectiveness and heat transfer rate as well as pumping power. However, SiC + Al2O3 dispersed hybrid nanofluid yields maximum performance index and hence this can be recommended for best coolant. For the same radiator size and heat transfer rate, pumping power increases by using Ag hybrid nanofluids leading to increase in engine thermal efficiency and hence reduction in engine fuel consumption. For same coolant flow rate and heat transfer rate, the radiator size reduces and pumping power increases by using Ag hybrid nanofluids leading to reduction in radiator size, weight and cost.

Effect of calcination temperature on microstructure and magnetic properties of Ni{sub 0.5}Zn{sub 0.25}Cu{sub 0.25} Fe{sub 2}O{sub 4} nanoparticles synthesized by sol-gel method

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

Pransisco, Prengki, E-mail: prengkipransisco@gmail.com, E-mail: afza@petronas.com.my; Shafie, Afza, E-mail: prengkipransisco@gmail.com, E-mail: afza@petronas.com.my; Guan, Beh Hoe, E-mail: beh.hoeguan@petronas.com.my

2014-10-24

This paper examines the effect of calcination process on the structural and magnetic properties material nanostructure composite of Ni{sub 0Ð}œ‡{sub 5}Zn{sub 0Ð}œ‡{sub 25}Cu{sub 0.25} Fe{sub 2}O{sub 4} ferrites. The samples were successfully prepared by sol-gel method at different calcination temperature, which are 600°C, 700°C, 800°C and 900°C. Morphological investigation, average crystallite size and microstructure of the material were examined by using X-ray diffraction (XRD) and confirmed by high resolution transmission electron microscope (HRTEM) and field emission scanning electron microscope (FESEM). The effects of calcination temperature on the magnetic properties were calculated by using vibrating sample magnetometer (VSM). The XRD resultmore » shows single-phase cubic spinel structure with interval average size 5.9-38 nm, and grain size microstructure of the material was increasing with temperature increases. The highest magnetization saturation was reached at a temperature 800°C with value 53.89 emu/g, and the value coercive force (Hc) was inversely with the grain size.« less

The Effect of Forging Variables on the Supersolvus Heat-Treatment Response of Powder-Metallurgy Nickel-Base Superalloys

NASA Astrophysics Data System (ADS)

Semiatin, S. L.; Shank, J. M.; Shiveley, A. R.; Saurber, W. M.; Gaussa, E. F.; Pilchak, A. L.

2014-12-01

The effect of subsolvus forging temperature and strain rate on the grain size developed during final supersolvus heat treatment (SSHT) of two powder-metallurgy, gamma-gamma prime superalloys, IN-100 and LSHR, was established. For this purpose, isothermal, hot compression tests were performed at temperatures ranging from 1144 K (871 °C) and 22 K (22 °C) below the respective gamma-prime solvus temperatures ( T γ') and strain rates between 0.0003 and 10 s-1. Deformed samples were then heat treated 20 K (20 °C) above the solvus for 1 h with selected additional samples exposed for shorter and longer times. For both alloys, the grain size developed during SSHT was in the range of 15 to 30 μm, except for those processing conditions consisting of pre-deformation at the highest temperature, i.e., T γ'—22 K ( T γ'—22 °C), and strain rates in the range of ~0.001 to 0.1 s-1. In these latter instances, the heat-treated grain size was approx. four times as large. The observations were interpreted in terms of the mechanisms of deformation during hot working and their effect on the driving forces for grain-boundary migration which controls the evolution of the gamma-grain size.

Entropic effects in the electric double layer of model colloids with size-asymmetric monovalent ions

NASA Astrophysics Data System (ADS)

Guerrero-García, Guillermo Iván; González-Tovar, Enrique; Olvera de la Cruz, Mónica

2011-08-01

The structure of the electric double layer of charged nanoparticles and colloids in monovalent salts is crucial to determine their thermodynamics, solubility, and polyion adsorption. In this work, we explore the double layer structure and the possibility of charge reversal in relation to the size of both counterions and coions. We examine systems with various size-ratios between counterions and coions (ion size asymmetries) as well as different total ion volume fractions. Using Monte Carlo simulations and integral equations of a primitive-model electric double layer, we determine the highest charge neutralization and electrostatic screening near the electrified surface. Specifically, for two binary monovalent electrolytes with the same counterion properties but differing only in the coion's size surrounding a charged nanoparticle, the one with largest coion size is found to have the largest charge neutralization and screening. That is, in size-asymmetric double layers with a given counterion's size the excluded volume of the coions dictates the adsorption of the ionic charge close to the colloidal surface for monovalent salts. Furthermore, we demonstrate that charge reversal can occur at low surface charge densities, given a large enough total ion concentration, for systems of monovalent salts in a wide range of ion size asymmetries. In addition, we find a non-monotonic behavior for the corresponding maximum charge reversal, as a function of the colloidal bare charge. We also find that the reversal effect disappears for binary salts with large-size counterions and small-size coions at high surface charge densities. Lastly, we observe a good agreement between results from both Monte Carlo simulations and the integral equation theory across different colloidal charge densities and 1:1-elec-trolytes with different ion sizes.

Linking human capital and enterprise sustainability in Indonesian medium-sized food manufacturing enterprises: the role of informal knowledge sharing practice

NASA Astrophysics Data System (ADS)

Sunardi, O.

2017-12-01

Medium-sized food manufacturing enterprises in Indonesia are significant in a number of contexts, in terms of their part to the national production (GDP) and their establishment to the employment. In term of their role to national production, manufacturing sector contributes the highest GDP by 85%. In this sector, food manufacturing subsector contributes the highest GDP. Nevertheless, they faced the same common problems: quality of human capital and sustainability issues. Previous government supplementary programs have been established to expand the human capital capability amongst medium enterprises. Adequate amount of fund has been apportioned to develop human capital, though, the medium enterprises sustainability is still in question. This study proposes and examines the human capital role from informal knowledge sharing perspective. By conducting qualitative approach through interviews to four informants in Indonesian medium-sized food manufacturing enterprises, a set of hypotheses is derived from this study for future quantitative study. This study indicates that human capital traits (diverse education background, employee skills, and employee experience) could leverage the practice of informal knowledge sharing. Constructs such as mutual trust and reciprocal intention could play as mediating variables, and cultural interpretation perspective could act as moderating factor to informal knowledge sharing effectiveness. In final, informal knowledge sharing is indicated to play as moderating variable for human capital policy and practice to support enterprise sustainability.

Optimisation of sewage sludge anaerobic digestion through co-digestion with OFMSW: Effect of collection system and particle size.

PubMed

Silvestre, Gracia; Bonmatí, August; Fernández, Belén

2015-09-01

The effect of organic fraction of municipal solid waste (OFMSW) loading rate and particulate size on the sewage sludge (SS) mesophilic anaerobic co-digestion was assessed in continuous stirred tank reactor at hydraulic retention time of 20days. The SS-OFMSW mixture composed by 54% of the volatile solids fed (inlet-VS), at OLR of 3.1kgCODm(-3)d(-1) (1.9kgVSm(-3)d(-1)), showed the highest increment on the volumetric methane production and yield of +200% and +59% respectively, under stable conditions. The effect of particulate size was assessed with the same mixture and same operational conditions but reducing the OFMSW particulate size from 20mm to 8mm with the aim to improve the hydrolysis step, but the results showed any influence in the OFMSW particulate size range analysed. In addition, specific biomass activity was assessed at the end of each co-digestion period. Results showed that OFMSW promoted β-oxidation syntrophic acetogens and the acetoclastic methanogens activity; although the last increase of the OFMSW percentage (from 47% to 54% inlet-VS) affected negatively the specific substrate activity, but not inhibitory effect was observed. Therefore, the results obtained in the continuous experiment could be related with some inhibitory or toxic effect and not due to hydrolysis limitation. The specific biomass activity test was demonstrated to be an interesting tool to evaluate and control the co-digestion process, especially when conventional parameters did not explain the behaviour of the biological system. Copyright © 2015 Elsevier Ltd. All rights reserved.

Comparison of methods of extracting information for meta-analysis of observational studies in nutritional epidemiology.

PubMed

Bae, Jong-Myon

2016-01-01

A common method for conducting a quantitative systematic review (QSR) for observational studies related to nutritional epidemiology is the "highest versus lowest intake" method (HLM), in which only the information concerning the effect size (ES) of the highest category of a food item is collected on the basis of its lowest category. However, in the interval collapsing method (ICM), a method suggested to enable a maximum utilization of all available information, the ES information is collected by collapsing all categories into a single category. This study aimed to compare the ES and summary effect size (SES) between the HLM and ICM. A QSR for evaluating the citrus fruit intake and risk of pancreatic cancer and calculating the SES by using the HLM was selected. The ES and SES were estimated by performing a meta-analysis using the fixed-effect model. The directionality and statistical significance of the ES and SES were used as criteria for determining the concordance between the HLM and ICM outcomes. No significant differences were observed in the directionality of SES extracted by using the HLM or ICM. The application of the ICM, which uses a broader information base, yielded more-consistent ES and SES, and narrower confidence intervals than the HLM. The ICM is advantageous over the HLM owing to its higher statistical accuracy in extracting information for QSR on nutritional epidemiology. The application of the ICM should hence be recommended for future studies.

Size, shape, and compositional effects on the order-disorder phase transitions in Au-Cu and Pt-M (M = Fe, Co, and Ni) nanocluster alloys.

PubMed

Kaatz, Forrest H; Bultheel, Adhemar

2018-08-24

Au-Cu and Pt-M (M = Fe, Co, and Ni) nanocluster alloys are currently being investigated world-wide by many researchers for their interesting catalytic and nanophase properties. The low temperature behavior of the phase diagrams is not well understood for alloys with nanometer sizes and shapes. We consider two models for low temperature ordering in the phase diagrams of Au-Cu and Pt-M nanocluster alloys. These models are valid for sizes ∼5 nm and approach bulk values for sizes ∼20 nm. We study the phase transitions in nanoclusters with cubic, octahedral, and cuboctahedral shapes, covering the compositions of interest. These models are based on studying the melting temperatures in nanoclusters using the regular solution, mixing model for alloys. From our data, experiments on nanocubes about 5 nm in size, of stoichiometric AuCu and PtM composition, could help differentiate between the models. Dispersion data shows that for the three shapes considered, octahedra have the highest percentage of surface atoms for the same relative diameter. We summarize the effects of structural ordering on the catalytic activity and suggest a method to avoid sintering during annealing of Pt-M alloys.

The effect of sterilization methods on the physical properties of silk sericin scaffolds.

PubMed

Siritientong, Tippawan; Srichana, Teerapol; Aramwit, Pornanong

2011-06-01

Protein-based biomaterials respond differently to sterilization methods. Since protein is a complex structure, heat, or irradiation may result in the loss of its physical or biological properties. Recent investigations have shown that sericin, a degumming silk protein, can be successfully formed into a 3-D scaffolds after mixing with other polymers which can be applied in skin tissue engineering. The objective of this study was to investigate the effectiveness of ethanol, ethylene oxide (EtO) and gamma irradiation on the sterilization of sericin scaffolds. The influence of these sterilization methods on the physical properties such as pore size, scaffold dimensions, swelling and mechanical properties, as well as the amount of sericin released from sericin/polyvinyl alcohol/glycerin scaffolds, were also investigated. Ethanol treatment was ineffective for sericin scaffold sterilization whereas gamma irradiation was the most effective technique for scaffold sterilization. Moreover, ethanol also caused significant changes in pore size resulting from shrinkage of the scaffold. Gamma-irradiated samples exhibited the highest swelling property, but they also lost the greatest amount of weight after immersion for 24 h compared with scaffolds obtained from other sterilization methods. The results of the maximum stress test and Young's modulus showed that gamma-irradiated and ethanol-treated scaffolds are more flexible than the EtO-treated and untreated scaffolds. The amount of sericin released, which was related to its collagen promoting effect, was highest from the gamma-irradiated scaffold. The results of this study indicate that gamma irradiation should have the greatest potential for sterilizing sericin scaffolds for skin tissue engineering.

Photocatalytic Applications of Electrospun TiO2 Nanofibres Embedded with Bimodal Sized and Prismatic Gold Nanoparticles.

PubMed

Gopika, G; Asha, A M; Sivakumar, N; Balakrishnan, A; Nair, S V; Subramanian, K R V

2015-09-01

In this paper, we have synthesized electrospun TiO2 nanofibers embedded with bimodal sized and prismatic gold nanoparticles. The surface plasmons generated in the gold nanoparticles were used to enhance the performance of photocatalysis. The photocatalytic conversion efficiencies of these bimodal sized/prismatic gold nanoparticles when embedded in electrospun TiO2 fibres showed an enhancement of upto 60% over bare fiber systems and also show higher efficiencies than electrospun fibrous systems embedded with unimodal sized gold nanoparticles. Anisotropic bimodal gold nanoparticles show the highest degree of photocatalytic activity. This may be attributed to greater density/concentration of nanoparticles with higher effective surface area and formation of a junction between the smaller and larger nanoparticles. Such a bimodally distributed range of nanoparticles could also lead to greater trapping of charge carriers at the TiO2 conduction band edge and promoting catalytic reactions on account of these trapped charges. This enhanced photocatalytic activity is explained by invoking different operating mechanisms such as improved surface area, greater trapping, coarse plasmon resonance and band effects. Thus, a useful applicability of the gold nanoparticles is shown in the area of photocatalysis.

Effect of sediment size on bioleaching of heavy metals from contaminated sediments of Izmir Inner Bay.

PubMed

Guven, Duyusen E; Akinci, Gorkem

2013-09-01

The effect of sediment size on metals bioleaching from bay sediments was investigated by using fine (< 45 microm), medium (45-300 microm), and coarse (300-2000 microm) size fractions of a sediment sample contaminated with Cr, Cu, Pb, and Zn. Chemical speciation of the metals in bulk and size fractions of sediment were studied before and after bioleaching. Microbial activity was provided with mixed cultures of Acidithiobacillus thiooxidans and Acidithiobacillus ferrooxidans. The bioleaching process was carried out in flask experiments for 48 days, by using 5% (W/V) of solid concentration in suspension. Bioleaching was found to be efficient for the removal of selected heavy metals from every size fraction of sediments, where the experiments with the smaller particles resulted in the highest solubilization ratios. At the end of the experimental period, Cr, Cu, Pb and Zn were solubilized to the ratios of 68%, 88%, 72%, and 91% from the fine sediment, respectively. Higher removal efficiencies can be explained by the larger surface area provided by the smaller particles. The changes in the chemical forms of metals were determined and most of the metal releases were observed from the reducible and organic fractions independent from grain size. Higher concentrations were monitored in the residual fraction after bioleaching period, suggesting they are trapped in this fraction, and cannot be solubilized under natural conditions.

Study of interactions between anionic exopolysaccharides produced by newly isolated probiotic bacteria and sodium caseinate.

PubMed

Abid, Yousra; Joulak, Ichrak; Ben Amara, Chedia; Casillo, Angela; Attia, Hamadi; Gharsallaoui, Adem; Azabou, Samia

2018-07-01

The present study aims to evaluate the interactions between four exopolysaccharides (EPS) produced by probiotic bacteria and sodium caseinate (Cas) in order to simulate their behavior in dairy products. Complexation between the produced EPS samples and Cas was investigated as a function of polysaccharide to protein ratio. The highest turbidity and average size of complexes were formed at an EPS/Cas ratio of 3 (corresponding to 1 g/L of EPS and 0.33 g/L of Cas) as a result of the combination of individual complexes to form aggregates. Zeta potential measurements and Cas surface hydrophobicity results suggested that complex formation occurred essentially through electrostatic attractions with a possible contribution of hydrophobic interaction for EPS-GM which was produced by Bacillus tequilensis-GM. Afterwards, the effect of pH on the complexation between biopolymers was studied when EPS and Cas concentrations were maintained constant at 1 and 0.33 g/L, respectively. pH was adjusted to 3.0 and 3.5, respectively. Results showed that the highest amount and sizes of EPS/Cas complexes were formed at pH 3.5 and that EPS-GM enabled to obtain the biggest and highest amount of aggregates. Therefore, the obtained results support the fact that the simultaneous presence of EPS and Cas in dairy products results in complexes formation via electrostatic interactions depending on EPS/Cas ratio and pH of the medium. Copyright © 2018 Elsevier B.V. All rights reserved.

Ultrafine particles are not major carriers of carcinogenic PAHs and their genotoxicity in size-segregated aerosols.

PubMed

Topinka, Jan; Milcova, Alena; Schmuczerova, Jana; Krouzek, Jiri; Hovorka, Jan

2013-06-14

Some studies suggest that genotoxic effects of combustion-related aerosols are induced by carcinogenic polycyclic aromatic hydrocarbons (c-PAHs) and their derivatives, which are part of the organic fraction of the particulate matter (PM) in ambient air. The proportion of the organic fraction in PM is known to vary with particle size. The ultrafine fraction is hypothesized to be the most important carrier of c-PAHs, since it possesses the highest specific surface area of PM. To test this hypothesis, the distribution of c-PAHs in organic extracts (EOMs) was compared for four size fractions of ambient-air aerosols: coarse (1

Play seriously: Effectiveness of serious games and their features in motor rehabilitation. A meta-analysis.

PubMed

Tăut, Diana; Pintea, Sebastian; Roovers, Jan-Paul W R; Mañanas, Miguel-Angel; Băban, Adriana

2017-01-01

Evidence for the effectiveness of serious games (SGs) and their various features is inconsistent in the motor rehabilitation field, which makes evidence based development of SGs a rare practice. To investigate the effectiveness of SGs in motor rehabilitation for upper limb and movement/balance and to test the potential moderating role of SGs features like feedback, activities, characters and background. We ran a meta-analysis including 61 studies reporting randomized controlled trials (RCTs), controlled trials (CTs) or case series designs in which at least one intervention for motor rehabilitation included the use of SGs as standalone or in combination. There was an overall moderate effect of SGs on motor indices, d = 0.59, [95% CI, 0.48, 0.71], p <  0.001. Regarding the game features, only two out of 17 moderators were statistically different in terms of effect sizes: type of activity (combination of group with individual activities had the highest effects), and realism of the scenario (fantasy scenarios had the highest effects). While we showed that SGs are more effective in improving motor upper limb and movement/balance functions compared to conventional rehabilitation, there were no consistent differences between various game features in their contribution to effects. Further research should systematically investigate SGs features that might have added value in improving effectiveness.

Detection of recurrent activation patterns across focal seizures: Application to seizure onset zone identification.

PubMed

Vila-Vidal, Manel; Principe, Alessandro; Ley, Miguel; Deco, Gustavo; Tauste Campo, Adrià; Rocamora, Rodrigo

2017-06-01

We introduce a method that quantifies the consistent involvement of intracranially monitored regions in recurrent focal seizures. We evaluated the consistency of two ictal spectral activation patterns (mean power change and power change onset time) in intracranial recordings across focal seizures from seven patients with clinically marked seizure onset zone (SOZ). We examined SOZ discrimination using both patterns in different frequency bands and periods of interest. Activation patterns were proved to be consistent across more than 80% of recurrent ictal epochs. In all patients, whole-seizure mean activations were significantly higher for SOZ than non-SOZ regions (P<0.05) while activation onset times were significantly lower for SOZ than for non-SOZ regions (P<0.001) in six patients. Alpha-beta bands (8-20Hz) achieved the highest patient-average effect size on the whole-seizure period while gamma band (20-70Hz) achieved the highest discrimination values between SOZ and non-SOZ sites near seizure onset (0-5s). Consistent spectral activation patterns in focal epilepsies discriminate the SOZ with high effect sizes upon appropriate selection of frequency bands and activation periods. The present method may be used to improve epileptogenic identification as well as pinpoint additional regions that are functionally altered during ictal events. Copyright © 2017 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.

Impact of particle size on distribution and human exposure of flame retardants in indoor dust.

PubMed

He, Rui-Wen; Li, Yun-Zi; Xiang, Ping; Li, Chao; Cui, Xin-Yi; Ma, Lena Q

2018-04-01

The effect of dust particle size on the distribution and bioaccessibility of flame retardants (FRs) in indoor dust remains unclear. In this study, we analyzed 20 FRs (including 6 organophosphate flame retardants (OPFRs), 8 polybrominated diphenyl ethers (PBDEs), 4 novel brominated flame retardants (NBFRs), and 2 dechlorane plus (DPs)) in composite dust samples from offices, public microenvironments (PME), and cars in Nanjing, China. Each composite sample (one per microenvironment) was separated into 6 size fractions (F1-F6: 200-2000µm, 150-200µm, 100-150µm, 63-100µm, 43-63µm, and <43µm). FRs concentrations were the highest in car dust, being 16 and 6 times higher than those in offices and PME. The distribution of FRs in different size fractions was Kow-dependent and affected by surface area (Log Kow=1-4), total organic carbon (Log Kow=4-9), and FR migration pathways into dust (Log Kow>9). Bioaccessibility of FRs was measured by the physiologically-based extraction test, with OPFR bioaccessibility being 1.8-82% while bioaccessible PBDEs, NBFRs, and DPs were under detection limits due to their high hydrophobicity. The OPFR bioaccessibility in 200-2000µm fraction was significantly higher than that of <43µm fraction, but with no difference among the other four fractions. Risk assessment was performed for the most abundant OPFR-tris(2-chloroethyl) phosphate. The average daily dose (ADD) values were the highest for the <43µm fraction for all three types of dust using total concentrations, but no consistent trend was found among the three types of dust if based on bioaccessible concentrations. Our results indicated that dust size impacted human exposure estimation of FRs due to their variability in distribution and bioaccessibility among different fractions. For future risk assessment, size selection for dust sampling should be standardized and bioaccessibility of FRs should not be overlooked. Copyright © 2018 Elsevier Inc. All rights reserved.

Optimum size of nanorods for heating application

NASA Astrophysics Data System (ADS)

Seshadri, G.; Thaokar, Rochish; Mehra, Anurag

2014-08-01

Magnetic nanoparticles (MNP's) have become increasingly important in heating applications such as hyperthermia treatment of cancer due to their ability to release heat when a remote external alternating magnetic field is applied. It has been shown that the heating capability of such particles varies significantly with the size of particles used. In this paper, we theoretically evaluate the heating capability of rod-shaped MNP's and identify conditions under which these particles display highest efficiency. For optimally sized monodisperse particles, the power generated by rod-shaped particles is found to be equal to that generated by spherical particles. However, for particles which are not mono dispersed, rod-shaped particles are found to be more effective in heating as a result of the greater spread in the power density distribution curve. Additionally, for rod-shaped particles, a dispersion in the radius of the particle contributes more to the reduction in loss power when compared to a dispersion in the length. We further identify the optimum size, i.e the radius and length of nanorods, given a bi-variate log-normal distribution of particle size in two dimensions.

Effects of biochemical and physical processes on concentrations and size distributions of dimethylaminium and trimethylaminium in atmospheric particles from marginal seas of China to the northwest Pacific Ocean

NASA Astrophysics Data System (ADS)

Hu, Q.; Yao, X.; Qu, K.; Cui, Z.; Gao, H.; Xie, H.

2017-12-01

This study aim to assess the effects of concentrations and size distributions of aminium ions in atmospheric particles from offshore to open oceans. Size-segregated dimethylaminium (DMA+) and trimethylaminium (TMA+) in atmospheric particles were measured during March-May, 2014. One cruise was over marginal seas of China, in which the concentrations of DMA+ and TMA+ in PM0.056-10 varied from 0.08 nmol m-3 to 0.43 nmol m-3 and from 0.10 to 0.27 nmol m-3, respectively. The two ions both had good positive correlations with subsurface chlorophyll-a maximum and salinity, respectively. The highest concentrations of (DMA+ + TMA+) were observed during cyanobacteria bloom period which happened in subsurface water. The results implied that the concentrations of DMA+ (TMA+) in marine atmospheric particles might be influenced by phytoplankton quantities and species in subsurface seawater. Another cruise was carried out from marginal seas of China to the northwest Pacific Ocean (NWPO). The concentrations of DMA+ and TMA+ in PM0.056-1.8 varied from 0.19 nmol m-3 to 1.53 nmol m-3 and from 0.57 to 3.85 nmol m-3, respectively. The highest (lowest) concentrations of (DMA+ + TMA+) were observed near the cyclonic (anticyclonic) eddy, indicating that the cyclonic (anticyclonic) eddy with high (low) chlorophyll-a enhanced (suppressed) DMA+ (TMA+) production in atmospheric particles. In addition, the dominant particle modes less than 0.2 μm for DMA+ (TMA+) were observed, ie., 0.13±0.02 μm for DMA+ over marginal seas of China, and 0.08±0.00 μm for TMA+ in NWPO, but if they were emitted via bubble bursting needed to be further researched.

Effect of Freeze-Thaw Cycles on Grain Size of Biochar

NASA Astrophysics Data System (ADS)

Dugan, B.; Liu, Z.; Masiello, C. A.; Gonnermann, H. M.; Nittrouer, J. A.

2015-12-01

Biochar may improve soil performance by altering soil physical properties such as porosity, density, hydraulic conductivity, and water holding capacity. Because these physical properties of soil-biochar mixtures are associated with the grain size of the soil and the biochar, they may change if biochar particles are physically broken down in the environment. In cold regions, biochar may be fragmented into smaller particles when water in biochar's internal pores expands during freezing. This expansion may mechanically break particles. In this study we investigate if freeze-thaw cycles affect grain size of biochars produced at two temperatures (350°C and 500°C) from four types of feedstock (mesquite, pine, sewage waste, and miscanthus). Prior to freeze-thaw cycles, biochar's internal porosity increases with pyrolysis temperature and also varies with feedstock type. In our study, the highest internal porosity is 0.82±0.11 for 500 °C miscanthus biochar and the lowest internal porosity is 0.27±0.01 for 350 °C sewage waste biochar. Our biochars also have different median grain diameter (D50) and aspect ratio (AR). The largest D50 is 4836±132 μm for 350 °C miscanthus biochar and the smallest D50 is 2238±13 μm for 350°C sewage waste biochar. The highest AR is 0.85±0.01 for 500 °C sewage waste biochar and the lowest AR is 0.31±0.01 for 350 °C miscanthus biochar. After characterizing the initial properties of biochars, we saturated our biochar using synthetic rain water and subjected them to 10 freeze-thaw cycles (freeze at -19±3°C for 8 hours and thaw at 20±0°C for 16 hours). We expect that D50 will be reduced and AR will be changed by freeze-thaw cycles and the effect will vary with biochar porosity. Ultimately this work will help constrain how biochar particle size changes due to freezing, which can be extrapolated to understand transients in soil performance associated with biochar particle size.

Characteristics of size-segregated carbonaceous aerosols in the Beijing-Tianjin-Hebei region.

PubMed

Guo, Yuhong

2016-07-01

Mass concentrations of organic carbon (OC) and elemental carbon (EC) in size-resolved aerosols were investigated at four sites (three cities and one country) in the Beijing-Tianjin-Hebei region from September 2009 to August 2011. The size distributions of OC and EC presented large evolutions among rural and urban sites, and among four seasons, with highest peaks of OC and EC in fine mode in urban areas during winter. Geometric mean diameters (GMDs) of OC and EC in fine particles at urban sites during winter were lower than those at rural site mainly due to effects of fine particle coagulation and organic compound repartitioning. Fossil fuel emissions were a dominant source of OC and EC in urban areas, while biomass burning was a major source of OC and EC at rural site. Trajectory clustering and CWT analysis showed that regional transport was an important contributor to OC and EC in Beijing.

Determination of CEC value (Cation Exchange Capacity) of Bentonites from North Aceh and Bener Meriah, Aceh Province, Indonesia using three methods

NASA Astrophysics Data System (ADS)

Rihayat, T.; Salim, S.; Arlina, A.; Fona, Z.; Jalal, R.; Alam, P. N.; Zaimahwati; Sami, M.; Syarif, J.; Juhan, N.

2018-03-01

Research on determination of value CEC (Cation Exchange Capacity) Bentonite North Aceh and Bener Meriah with three methods has been studied. The purpose of this study was to determine the value of CEC bentonite North Aceh and Bener Meriah. The methods used in this research were pH equilibrium, BaCl2/MgSO4 and the adsorption of methylene blue. These three methods used to determine, compare, and calculation of the CEC value and determine the effect of particle size of bentonite on the value of the CEC. Bentonite North Aceh and Bener Meriah sieved with particle sizes of 80, 100, 150, 200, 250 mesh. The results showed that determination of the value of CEC bentonite North Aceh using BaCl2/MgSO4 with a particle size of 250 mesh is the value of the highest, reaching 79.09 meq/100 g.

[Density, size structure and reproductive activity of the pink conch Eustrombus gigas (Mesogastropoda: Strombidae) in Banco Chinchorro, Mexico].

PubMed

Cala, Yuself R; Navarrete, Alberto de Jesús; Ocaña, Frank A; Rivera, José Oliva

2013-12-01

The pink conch Eustrombus gigas is an important fisheries resource. At the regional level in the Caribbean, over-exploitation and habitat destruction have caused a decrease in the abundance of this resource. In order to provide necessary information for the species management in Mexico, this work aimed to analyze the total density, adult density, size structure and reproductive behavior of pink conch population at Banco Chinchorro during 2009-2010. Data from three seasons were obtained (rainy, dry and cold fronts periods) in three areas: Norte (North), Centro (Center) and Sur (South). The organisms were separated into two groups: (a) the criteria based upon legal harvest in Mexico: legal size conchs (siphonal length > 200 mm) and illegal size conchs (siphonal length < 200 mm), and (b) the criteria based upon sexual maturity using the 15 mm lip thickness standard: lip < 15 mm as juvenile conch and lip > or = 15 mm as adult conch. Copulation, spawning, egg masses and aggregations were evaluated as reproductive evidences. The highest total density was observed during the dry season with 384ind./ha, and the lowest during the rainy season with 127ind./ha. The highest density was reported at Sur (385ind./ha) and the lowest at Norte (198ind./ ha). The highest adult density was observed during the rainy season (8.33ind./ha), and the lowest occurred in the dry season (6.1 ind./ha). Adult density values were 5.55, 7.05 and 8.33ind./ha for Centro, Sur and Norte areas, respectively. Adult densities were lower than the threshold needed for reproduction, and 42% of the population may be vulnerable to fishing, as they had the minimum size for catch (Lsi 200 mm). Furthermore, only 2.2% of the population reached a Gl > 15 mm as sexual maturity indicator. During the study period, only six evidences of reproductive activity were observed. The smaller densities reported at Banco Chinchorro may cause reproduction events to be almost absent which in turn is sufficient evidence to show that the Allee Effect is acting on the queen conch population and there is an urgent need of fishery closure. Three important points were proposed for management of queen conch at Banco Chinchorro: total closure of fishing, systematic assessment of the conch population and the implementation of conch fishing refuge.

The Effect of Cellulose Acetate Concentration from Coconut Nira on Ultrafiltration Membrane Characters

NASA Astrophysics Data System (ADS)

Vaulina, E.; Widyaningsih, S.; Kartika, D.; Romdoni, M. P.

2018-04-01

Cellulose acetate is one of material in produce ultrafiltration membrane. Many efforts have been done to produce cellulose acetate from natural product to replace commercial one. In this research, ultrafiltration membrane has been produced from coconut flower water (nira). Ultrafiltration membrane is widely used in separation processes. This research aims to determine the characteristics of ultrafiltration membrane at a various concentration of cellulose acetate. The ultrafiltration membrane is conducted by phase inversion method at various concentration of cellulose acetate. The cellulose acetate concentration was 20%, 23% and 25% (w/w) with formamide as additives. The results showed that the greater the concentration of cellulose acetate, the smaller the flux value. The highest flux was a membrane with 20% cellulose acetate concentration with water flux value 55.34 L/(m2. h). But the greater the concentration of cellulose acetate the greater the rejection. The highest rejection value was on a membrane with 25% cellulose acetate concentration of 82.82%. While from the tensile strength test and the pore size analysis, the greater the cellulose acetate concentration the greater the tensile strength and the smaller the pore size

A-site compositional effects in Ga-doped hollandite materials of the form BaxCsyGa2x+yTi8−2x−yO16: implications for Cs immobilization in crystalline ceramic waste forms

PubMed Central

Xu, Yun; Wen, Yi; Grote, Rob; Amoroso, Jake; Shuller Nickles, Lindsay; Brinkman, Kyle S.

2016-01-01

The hollandite structure is a promising crystalline host for Cs immobilization. A series of Ga-doped hollandite BaxCsyGa2x+yTi8−2x−yO16 (x = 0, 0.667, 1.04, 1.33; y = 1.33, 0.667, 0.24, 0) was synthesized through a solid oxide reaction method resulting in a tetragonal hollandite structure (space group I4/m). The lattice parameter associated with the tunnel dimension was found to increases as Cs substitution in the tunnel increased. A direct investigation of cation mobility in tunnels using electrochemical impedance spectroscopy was conducted to evaluate the ability of the hollandite structure to immobilize cations over a wide compositional range. Hollandite with the largest tunnel size and highest aspect ratio grain morphology resulting in rod-like microstructural features exhibited the highest ionic conductivity. The results indicate that grain size and optimized Cs stoichiometry control cation motion and by extension, the propensity for Cs release from hollandite. PMID:27273791

Technical Efficiency of Hospitals in Tehran, Iran.

PubMed

Kakeman, Edris; Rahimi Forushani, Abbas; Dargahi, Hossein

2016-04-01

Nowadays, restriction on access and optimum use of resources is the main challenge of development in all organizations. Therefore, the aim of this study was to determine the technical efficiency and its factors, influencing hospitals of Tehran. This research was a descriptive-analytical and retrospective study conducted in 2014-2015. Fifty two hospitals with public, private, and social security ownership type were selected for this study. The required data was collected by a researcher-made check list in 3 sections of background data, inputs and outputs. The data was analyzed by DEAP 1.0.2, and STATA-13 technique. Seventeen (31/48) of hospitals had the efficiency score of 1 as the highest technical efficiency. The highest average score of efficiency was related to social security hospitals as 84.32, and then the public and private hospitals with the average of 84.29 and 79.64 respectively. Tobit regression results showed that the size, type of practice, and ownership of hospitals were effective on the degree of their technical efficiency. However, there was no significant correlation between teaching / non-teaching hospitals with technical efficiency. Establishment of competition system among hospitals, constitution of medium size hospitals and allocation of budget to hospitals based on national accreditation system are recommended.

Solid Catalyst Nanoparticles derived from Oil-Palm Empty Fruit Bunches (OP-EFB) as a Renewable Catalyst for Biodiesel Production

NASA Astrophysics Data System (ADS)

Husin, H.; Asnawi, T. M.; Firdaus, A.; Husaini, H.; Ibrahim, I.; Hasfita, F.

2018-05-01

Solid nanocatalyst derived from oil-palm empty fruit bunches (OP-EFB) fiber was successfully synthesized and its application for biodiesel production was investigated. The OPEFB was treated by burning, milling and heating methods to generate ashes in a nanoparticle size. The nanoparticle palm-bunch ash was characterized by scanning electron microscopy (SEM) and x-ray diffraction (XRD). The effects of the calcination temperature and catalyst amounts for transesterification reactions were investigated. XRD analysis of palm bunch ash exhibited that the highest composition of peaks characteristic were potassium oxide (K2O). SEM analysis showed that the nano palm bunch ash have a particle size ranging of 150-400 nm. The highest conversion of palm-oil to biodiesel reach to 97.90% was observed by using of palm bunch ash nanocatalyst which heated at 600°C, 3 h reaction time and 1% catalyst amount. Reusability of palm bunch ash catalysts was also examined. It was found that of its high active sites, reusable solid catalyst was obtained by just heating of palm bunch ash. It has a capability to reduce not only the amount of catalyst consumption but also reduce the reaction time of transesterification process.

Effect of Cr3+ substitution on AC susceptibility of Ba hexaferrite nanoparticles

NASA Astrophysics Data System (ADS)

Slimani, Y.; Baykal, A.; Manikandan, A.

2018-07-01

In this study, nano-sized particles of BaCrxFe12-xO19 (0.0 ≤ x ≤ 1.0) hexaferrite were fabricated through citrate auto gel combustion process and the impact of Cr-ion substitution on ac magnetic susceptibility properties of Ba-hexaferrite were explored. X-ray powder diffraction (XRD) measurements approved the purity of prepared samples and showed a reduction of the average crystallite size with increasing the content of Cr. Transmission electron microscopy (TEM) observation indicated the hexagonal morphology of all samples. AC susceptibility measurements displayed a frequency dependence of the magnetic responses. These measurements indicated that there are strong magnetic interactions (which is the highest for BaCr0.3Fe11.7O19 NP) between particles which cause a superspin glass-like (SSG) behavior at low temperatures. Estimating the values of loss power density revealed an increase of loss power density with increasing Cr-substitution element. The relative sensitivity of the prepared MNPs to the variation of applied frequency is very influenced by Cr-substitution and is highest in BaCr0.3Fe11.7O19 MNPs, suggesting that this sample can be considered as magnetic nanomaterial for hyperthermia and for many other applications.

Carbon nanotube scaffolds with controlled porosity as electromagnetic absorbing materials in the gigahertz range

NASA Astrophysics Data System (ADS)

González, M.; Crespo, M.; Baselga, J.; Pozuelo, J.

2016-05-01

Control of the microscopic structure of CNT nanocomposites allows modulation of the electromagnetic shielding in the gigahertz range. The porosity of CNT scaffolds has been controlled by two freezing protocols and a subsequent lyophilization step: fast freezing in liquid nitrogen and slow freezing at -20 °C. Mercury porosimetry shows that slowly frozen specimens present a more open pore size (100-150 μm) with a narrow distribution whereas specimens frozen rapidly show a smaller pore size and a heterogeneous distribution. 3D-scaffolds containing 3, 4, 6 and 7% CNT were infiltrated with epoxy and specimens with 2, 5 and 8 mm thicknesses were characterized in the GHz range. Samples with the highest pore size and porosity presented the lowest reflected power (about 30%) and the highest absorbed power (about 70%), which allows considering them as electromagnetic radiation absorbing materials.Control of the microscopic structure of CNT nanocomposites allows modulation of the electromagnetic shielding in the gigahertz range. The porosity of CNT scaffolds has been controlled by two freezing protocols and a subsequent lyophilization step: fast freezing in liquid nitrogen and slow freezing at -20 °C. Mercury porosimetry shows that slowly frozen specimens present a more open pore size (100-150 μm) with a narrow distribution whereas specimens frozen rapidly show a smaller pore size and a heterogeneous distribution. 3D-scaffolds containing 3, 4, 6 and 7% CNT were infiltrated with epoxy and specimens with 2, 5 and 8 mm thicknesses were characterized in the GHz range. Samples with the highest pore size and porosity presented the lowest reflected power (about 30%) and the highest absorbed power (about 70%), which allows considering them as electromagnetic radiation absorbing materials. Electronic supplementary information (ESI) available: Scheme of hydrogenated derivative of diglycidyl ether of bisphenol-A (HDGEBA) and m-xylylenediamine; X-ray diffractograms of pristine CNT and oxidized CNT; glass transition temperatures of composites; electromagnetic shielding analysis in the 1-18 GHz frequency range. See DOI: 10.1039/c6nr02133f

Treatment Effect in Earlier Trials of Patients With Chronic Medical Conditions: A Meta-Epidemiologic Study.

PubMed

Alahdab, Fares; Farah, Wigdan; Almasri, Jehad; Barrionuevo, Patricia; Zaiem, Feras; Benkhadra, Raed; Asi, Noor; Alsawas, Mouaz; Pang, Yifan; Ahmed, Ahmed T; Rajjo, Tamim; Kanwar, Amrit; Benkhadra, Khalid; Razouki, Zayd; Murad, M Hassan; Wang, Zhen

2018-03-01

To determine whether the early trials in chronic medical conditions demonstrate an effect size that is larger than that in subsequent trials. We identified randomized controlled trials (RCTs) evaluating a drug or device in patients with chronic medical conditions through meta-analyses (MAs) published between January 1, 2007, and June 23, 2015, in the 10 general medical journals with highest impact factor. We estimated the prevalence of having the largest effect size or heterogeneity in the first 2 published trials. We evaluated the association of the exaggerated early effect with several a priori hypothesized explanatory variables. We included 70 MAs that had included a total of 930 trials (average of 13 [range, 5-48] RCTs per MA) with average follow-up of 24 (range, 1-168) months. The prevalence of the exaggerated early effect (ie, proportion of MAs with largest effect or heterogeneity in the first 2 trials) was 37%. These early trials had an effect size that was on average 2.67 times larger than the overall pooled effect size (ratio of relative effects, 2.67; 95% CI, 2.12-3.37). The presence of exaggerated effect was not significantly associated with trial size; number of events; length of follow-up; intervention duration; number of study sites; inpatient versus outpatient setting; funding source; stopping a trial early; adequacy of random sequence generation, allocation concealment, or blinding; loss to follow-up or the test for publication bias. Trials evaluating treatments of chronic medical conditions published early in the chain of evidence commonly demonstrate an exaggerated treatment effect compared with subsequent trials. At the present time, this phenomenon remains unpredictable. Considering the increasing morbidity and mortality of chronic medical conditions, decision makers should act on early evidence with caution. Copyright © 2017 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.

Evaluation of an Electrostatic Dust Removal System with Potential Application in Next-Step Fusion Devices

NASA Technical Reports Server (NTRS)

Friesen, F. Q. L.; John, B.; Skinner, C. H.; Roquemore, A. L.; Calle, C. I.

2011-01-01

The ability to manage inventories of carbon, tritium, and high-Z elements in fusion plasmas depends on means for effective dust removal. A dust conveyor, based on a moving electrostatic potential well, was tested with particles of tungsten, carbon, glass and sand. A digital microscope imaged a representative portion of the conveyor, and dust particle size and volume distributions were derived before and after operation. About 10 cu mm volume of carbon and tungsten particles were moved in under 5 seconds. The highest driving amplitude tested of 3 kV was the most effective. The optimal driving frequency was 210 Hz (maximum tested) for tungsten particles, decreasing to below 60 Hz for the larger sand particles. Measurements of particle size and volume distributions after 10 and 100 cycles show the breaking apart of agglomerated carbon, and the change in particle distribution over short timescales 1 s).

Behavioral and Emotional Problems Associated With Convergence Insufficiency in Children: An Open Trial.

PubMed

Borsting, Eric; Mitchell, G Lynn; Arnold, L Eugene; Scheiman, Mitchell; Chase, Christopher; Kulp, Marjean; Cotter, Susan

2016-10-01

This study investigated behavioral and emotional characteristics of children with convergence insufficiency (CI), before and after treatment with office-based vergence accommodative therapy (OBVAT). Parents of 44 children ages 9 to 17 years with symptomatic CI completed the Conners 3 ADHD Index and the Child Behavior Checklist (CBCL) before and after OBVAT. Pre-treatment scores were compared with normative data and post-treatment scores were compared with baseline using the Wilcoxon sign rank test. Following OBVAT, CI children showed a significant mean improvement (p < .0001, effect size of 0.58) on the Conners 3 ADHD Index with the largest changes occurring in the 23 children who scored the highest at baseline. On the CBCL, anxious/depressed, somatic, and internalizing problems improved significantly (p < .001, effect sizes of -0.36, -1.15, and -0.67, respectively). In an open trial, attention and internalizing problems improved significantly following treatment for CI. © The Author(s) 2013.

Maximizing return on socioeconomic investment in phase II proof-of-concept trials.

PubMed

Chen, Cong; Beckman, Robert A

2014-04-01

Phase II proof-of-concept (POC) trials play a key role in oncology drug development, determining which therapeutic hypotheses will undergo definitive phase III testing according to predefined Go-No Go (GNG) criteria. The number of possible POC hypotheses likely far exceeds available public or private resources. We propose a design strategy for maximizing return on socioeconomic investment in phase II trials that obtains the greatest knowledge with the minimum patient exposure. We compare efficiency using the benefit-cost ratio, defined to be the risk-adjusted number of truly active drugs correctly identified for phase III development divided by the risk-adjusted total sample size in phase II and III development, for different POC trial sizes, powering schemes, and associated GNG criteria. It is most cost-effective to conduct small POC trials and set the corresponding GNG bars high, so that more POC trials can be conducted under socioeconomic constraints. If δ is the minimum treatment effect size of clinical interest in phase II, the study design with the highest benefit-cost ratio has approximately 5% type I error rate and approximately 20% type II error rate (80% power) for detecting an effect size of approximately 1.5δ. A Go decision to phase III is made when the observed effect size is close to δ. With the phenomenal expansion of our knowledge in molecular biology leading to an unprecedented number of new oncology drug targets, conducting more small POC trials and setting high GNG bars maximize the return on socioeconomic investment in phase II POC trials. ©2014 AACR.

Comparison of parameters affecting GNP-loaded choroidal melanoma dosimetry; Monte Carlo study

NASA Astrophysics Data System (ADS)

Sharabiani, Marjan; Asadi, Somayeh; Barghi, Amir Rahnamai; Vaezzadeh, Mehdi

2018-04-01

The current study reports the results of tumor dosimetry in the presence of gold nanoparticles (GNPs) with different sizes and concentrations. Due to limited number of works carried out on the brachytherapy of choroidal melanoma in combination with GNPs, this study was performed to determine the optimum size and concentration for GNPs which contributes the highest dose deposition in tumor region, using two phantom test cases namely water phantom and a full Monte Carlo model of human eye. Both water and human eye phantoms were simulated with MCNP5 code. Tumor dosimetry was performed for a typical point photon source with an energy of 0.38 MeV as a high energy source and 103Pd brachytherapy source with an average energy of 0.021 MeV as a low energy source in water phantom and eye phantom respectively. Such a dosimetry was done for different sizes and concentrations of GNPs. For all of the diameters, increase in concentration of GNPs resulted in an increase in dose deposited in the region of interest. In a certain concentration, GNPs with larger diameters contributed more dose to the tumor region, which was more pronounced using eye phantom. 100 nm was reported as the optimum size in order to achieve the highest energy deposition within the target. This work investigated the optimum parameters affecting macroscopic dose enhancement in GNP-aided brachytherapy of choroidal melanoma. The current work also had implications on using low energy photon sources in the presence of GNPs to acquire the highest dose enhancement. This study is conducted through four different sizes and concentrations of GNPs. Considering the sensitivity of human eye tissue, in order to report the precise optimum parameters affecting radiosensitivity, a comprehensive study on a wide range of sizes and concentrations are required.

Conspicuity of renal calculi at unenhanced CT: effects of calculus composition and size and CT technique.

PubMed

Tublin, Mitchell E; Murphy, Michael E; Delong, David M; Tessler, Franklin N; Kliewer, Mark A

2002-10-01

To determine the effects of calculus size, composition, and technique (kilovolt and milliampere settings) on the conspicuity of renal calculi at unenhanced helical computed tomography (CT). The authors performed unenhanced CT of a phantom containing 188 renal calculi of varying size and chemical composition (brushite, cystine, struvite, weddellite, whewellite, and uric acid) at 24 combinations of four kilovolt (80-140 kV) and six milliampere (200-300 mA) levels. Two radiologists, who were unaware of the location and number of calculi, reviewed the CT images and recorded where stones were detected. These observations were compared with the known positions of calculi to generate true-positive and false-positive rates. Logistic regression analysis was performed to investigate the effects of stone size, composition, and technique and to generate probability estimates of detection. Interobserver agreement was estimated with kappa statistics. Interobserver agreement was high: the mean kappa value for the two observers was 0.86. The conspicuity of stone fragments increased with increasing kilovolt and milliampere levels for all stone types. At the highest settings (140 kV and 300 mA), the detection threshold size (ie, the size of calculus that had a 50% probability of being detected) ranged from 0.81 mm + 0.03 (weddellite) to 1.3 mm + 0.1 (uric acid). Detection threshold size for each type of calculus increased up to 1.17-fold at lower kilovolt settings and up to 1.08-fold at lower milliampere settings. The conspicuity of small renal calculi at CT increases with higher kilovolt and milliampere settings, with higher kilovolts being particularly important. Small uric acid calculi may be imperceptible, even with maximal CT technique.

Simultaneous saccharification and fermentation of Eastern redcedar heartwood and sapwood using a novel size reduction technique.

PubMed

Ramachandriya, Karthikeyan D; Wilkins, Mark; Pardo-Planas, Oscar; Atiyeh, Hasan K; Dunford, Nurhan T; Hiziroglu, Salim

2014-06-01

This study investigated the effect of two wood zones (sapwood versus heartwood) and size reduction techniques [Crumbles® (Crumbles® is a registered trademark of Forest Concepts, LLC, Auburn, WA, USA) particles versus ground particles] on wood glucan-to-ethanol yield after acid bisulfite pretreatment and simultaneous saccharification and fermentation (SSF) of Eastern redcedar. SSFs were conducted at 8% solids loading (w/w dry basis) using Accellerase® 1500 at a loading of 46FPU/g glucan and Saccharomyces cerevisiae D5A for ethanol fermentation. The size reduction technique had no effect on ethanol yield. However, sapwood glucan-to-ethanol yields were significantly greater than heartwood yields. The highest wood glucan-to-ethanol yield of 187L/dryMg (95% of theoretical) was achieved with sapwood crumbled particles in 240h. Ground sapwood, crumbled heartwood and ground heartwood achieved ethanol yields of 89%, 81% and 80% of theoretical in 240h, respectively. Preliminary mass balances showed 100% glucan recovery with crumbled sapwood and extensive (72%) delignification. Copyright © 2014 Elsevier Ltd. All rights reserved.

Evaluation of anti-cholinesterase, antibacterial and cytotoxic activities of green synthesized silver nanoparticles using from Millettia pinnata flower extract.

PubMed

Rajakumar, Govindasamy; Gomathi, Thandapani; Thiruvengadam, Muthu; Devi Rajeswari, V; Kalpana, V N; Chung, Ill-Min

2017-02-01

The aim of this study is to develop an easy and eco-friendly method for the synthesis of Ag-NPs using extracts from the medicinal plant, Millettia pinnata flower extract and investigate the effects of Ag-NPs on acetylcholinesterase (AChE), butyrylcholinesterase (BChE), antibacterial and cytotoxicity activity. UV-Vis peak at 438 nm confirmed the Ag-NPs absorbance. The SEM analysis results confirmed the presence of spherical shaped Ag-NPs by a huge disparity in the particle size distribution with an average size of 49 ± 0.9 nm. TEM images revealed the formation of Ag-NPs with spherical shape and sizes in the range between 16 and 38 nm. The Ag-NPs showed an excellent inhibitory efficacy against AChE and BChE. The highest antibacterial activity was found against Escherichia coli (20.25 ± 0.91 mm). These nanoparticles showed the cytotoxic effects against brine shrimp (artemia saliana) nauplii with a LD 50 value of 33.92. Copyright © 2016 Elsevier Ltd. All rights reserved.

Supercritical carbon dioxide (SC-CO2) extraction of essential oil from Swietenia mahagoni seeds

NASA Astrophysics Data System (ADS)

Norodin, N. S. M.; Salleh, L. M.; Hartati; Mustafa, N. M.

2016-11-01

Swietenia mahagoni (Mahogany) is a traditional plant that is rich with bioactive compounds. In this study, process parameters such as particle size, extraction time, solvent flowrate, temperature and pressure were studied on the extraction of essential oil from Swietenia mahagoni seeds by using supercritical carbon dioxide (SC-CO2) extraction. Swietenia mahagoni seeds was extracted at a pressure of 20-30 MPa and a temperature of 40-60°C. The effect of particle size on overall extraction of essential oil was done at 30 MPa and 50°C while the extraction time of essential oil at various temperatures and at a constant pressure of 30 MPa was studied. Meanwhile, the effect of flowrate CO2 was determined at the flowrate of 2, 3 and 4 ml/min. From the experimental data, the extraction time of 120 minutes, particle size of 0.5 mm, the flowrate of CO2 of 4 ml/min, at a pressure of 30 MPa and the temperature of 60°C were the best conditions to obtain the highest yield of essential oil.

Detection of periimplant fenestration and dehiscence with the use of two scan modes and the smallest voxel sizes of a cone-beam computed tomography device.

PubMed

de-Azevedo-Vaz, Sergio Lins; Vasconcelos, Karla de Faria; Neves, Frederico Sampaio; Melo, Saulo Leonardo Sousa; Campos, Paulo Sérgio Flores; Haiter-Neto, Francisco

2013-01-01

To assess the accuracy of cone-beam computed tomography (CBCT) in periimplant fenestration and dehiscence detection, and to determine the effects of 2 voxel sizes and scan modes. One hundred titanium implants were placed in bovine ribs in which periimplant fenestration and dehiscence were simulated. CBCT images were acquired with the use of 3 protocols of the i-CAT NG unit: A) 0.2 mm voxel size half-scan (180°); B) 0.2 mm voxel size full-scan (360°); and C) 0.12 mm voxel size full scan (360°). Receiver operating characteristic curves and diagnostic values were obtained. The Az values were compared with the use of analysis of variance. The Az value for dehiscence in protocol A was significantly lower than those of B or C (P < .01). They did not statistically differ for fenestration (P > .05). Protocol B yielded the highest values. The voxel sizes did not affect fenestration and dehiscence detection, and for dehiscence full-scan performed better than half-scan. Copyright © 2013 Elsevier Inc. All rights reserved.

Threatened species richness along a Himalayan elevational gradient: quantifying the influences of human population density, range size, and geometric constraints.

PubMed

Paudel, Prakash Kumar; Sipos, Jan; Brodie, Jedediah F

2018-02-07

A crucial step in conserving biodiversity is to identify the distributions of threatened species and the factors associated with species threat status. In the biodiversity hotspot of the Himalaya, very little is known about which locations harbour the highest diversity of threatened species and whether diversity of such species is related to area, mid-domain effects (MDE), range size, or human density. In this study, we assessed the drivers of variation in richness of threatened birds, mammals, reptiles, actinopterygii, and amphibians along an elevational gradient in Nepal Himalaya. Although geometric constraints (MDE), species range size, and human population density were significantly related to threatened species richness, the interaction between range size and human population density was of greater importance. Threatened species richness was positively associated with human population density and negatively associated with range size. In areas with high richness of threatened species, species ranges tend to be small. The preponderance of species at risk of extinction at low elevations in the subtropical biodiversity hotspot could be due to the double impact of smaller range sizes and higher human density.

Biogas production from rice straw by solid-state anaerobic digestion

NASA Astrophysics Data System (ADS)

Shitophyta, Lukhi Mulia; Budiyono, Fuadi, Ahmad M.

2015-12-01

Biogas production from lignocellulosic biomass can be used as an alternative fuel to replace fossil fuels. Lignocellulose can be obtained from agricultural crop residues, such as rice straw. The aims of this study were to determine the effects of F/I ratio, total solid content, and physical pretreatment on biogas production by solid-state anaerobic digestion. The kinetics of biogas production were also examined in this study. The results showed that the biogas yield decreased by the increasing of F/I ratio. Meanwhile, the increase TS content of 22% to 24% also decreased the biogas yield. Physical pretreatment had no a significant effect on biogas yield (p > 0.05). The highest biogas yield of 248.4 L/kg VS was obtained at an F/I ratio of 2, TS content of 22%, and particle size of 2 mm. The kinetics of biogas production from rice straw followed the first-order kinetic model with the highest rate constant (k) of 0.0861 day-1.

Intrapersonal characteristics of body-related guilt, shame, pride, and envy in Canadian adults.

PubMed

Pila, Eva; Brunet, Jennifer; Crocker, Peter R E; Kowalski, Kent C; Sabiston, Catherine M

2016-03-01

This study examined differences in body-related shame, guilt, pride, and envy based on intrapersonal characteristics of sex, age, and weight status in 527 Canadian adults. Compared to men, women reported significantly higher shame and guilt contextualized to the body. No sex differences were observed for envy or pride. Middle-aged adults reported higher shame and lower pride compared with young adults, whereas no age differences were observed with body-related guilt. Meanwhile, shame and guilt were highest for individuals who had overweight or obese weight status, and pride was highest in individuals with average weight status. Overall, effect sizes were small and there were no significant interaction effects between sex, age, and weight status across body-related emotions. Further research is needed to capture similarities and differences of body-related self-conscious emotions between intrapersonal characteristics, to aid the development of intervention strategies to manage this important dimension of body image. Copyright © 2016 Elsevier Ltd. All rights reserved.

Urea photosynthesis inside polyelectrolyte capsules: effect of confined media.

PubMed

Shchukin, Dmitry G; Möhwald, Helmuth

2005-06-07

The influence of the restricted volume of poly(styrene sulfonate)/poly(allylamine hydrochloride) capsules of different size (2.2, 4.2, and 8.1 microm) on the TiO2-assisted photosynthesis of urea from inorganic precursors (CO2 and NO(3-)) in aqueous solution was demonstrated. Poly(vinyl alcohol) was employed as electron donor to facilitate the photosynthetic process. Decreasing the size of the confined microvolume of polyelectrolyte capsules accelerates the NO(3-) photoreduction, which is a limiting stage of the urea photosynthesis and, correspondingly, increases the efficiency of urea production. The highest yield of urea photosynthesis (37%) was achieved for Cu-modified TiO2 nanoparticles encapsulated inside 2.2 microm poly(styrene sulfonate)/poly(allylamine hydrochloride) capsules.

The effect of hydrophilicity of graphene oxide as additive towards performance of polysulfone membrane

NASA Astrophysics Data System (ADS)

Jamalludin, Mohd Riduan; Harun, Zawati; Zakaria, M. S.; Rahim, Wan Mohd Faizal Wan Abd; Khor, C. Y.; Rosli, M. U.; Ishak, Muhammad Ikman; Nawi, M. A. M.; Shahrin, Suhaimi

2017-09-01

This study investigates the effect of hydrophilicity of graphene oxide as additive towards properties and performance on polysulfone (PSf) membrane. A polysulfone (PSf) membrane containing graphene oxide (GO) with different content was prepared via phase inversion technique. Characterization on the fabricated membrane were water contact angle measurement, porosity and mean pore size. The effects of PSf/GO were further investigated in terms of permeation test, rejection test and antifouling test. Based on the result obtained, PSf membrane incorporating with GO additive shows better capability to permeate more water compared to unfilled PSf membrane. The PSf/GO membrane were able to increase the permeate rate rapidly with the highest value is given by sample 4 (consist of 0.7 g of GO) at 571.78 J/m2h. Furthermore, water contact angle confirmed the hydrophilicity of this membrane at 62°. The transmembrane fouling activity showed that GO embedded in PSf membrane has improved tremendously. In addition, this study revealed that 0.7g of GO had the highest permeation test, rejection test and antifouling test.

Heart Disease Death Rates in Low Versus High Land Elevation Counties in the U.S.

PubMed

Hart, John

2015-01-01

Previous research on land elevation and cancer death rates in the U.S. revealed lower cancer death rates in higher elevations. The present study further tests the possible effect of land elevation on a diffident health outcome, namely, heart disease death rates. U.S. counties not overlapping in their land elevations according to their lowest and highest elevation points were identified. Using an ecological design, heart disease death rates for two races (black and white) corresponding to lower elevation counties were compared to heart disease death rates in higher land elevation counties using the two-sample t-test and effect size statistics. Death rates in higher land elevation counties for both races were lower compared to the death rates in lower land elevation counties (p < 0.001) with large effect sizes (of > 0.70). Since this is an observational study, no causal inference is claimed, and further research is indicated to verify these findings.

Heart Disease Death Rates in Low Versus High Land Elevation Counties in the U.S

PubMed Central

2015-01-01

Previous research on land elevation and cancer death rates in the U.S. revealed lower cancer death rates in higher elevations. The present study further tests the possible effect of land elevation on a diffident health outcome, namely, heart disease death rates. U.S. counties not overlapping in their land elevations according to their lowest and highest elevation points were identified. Using an ecological design, heart disease death rates for two races (black and white) corresponding to lower elevation counties were compared to heart disease death rates in higher land elevation counties using the two-sample t-test and effect size statistics. Death rates in higher land elevation counties for both races were lower compared to the death rates in lower land elevation counties (p < 0.001) with large effect sizes (of > 0.70). Since this is an observational study, no causal inference is claimed, and further research is indicated to verify these findings. PMID:26674102

Ontogenetic variation in food consumption of rusty crayfish (Orconectes rusticus) in a central New York stream

USGS Publications Warehouse

Johnson, J. H.; Nack, C.C.

2010-01-01

We examined feeding periodicity of three size groups of the rusty crayfish (Orconectes rusticus) at four-hour intervals over a 28-hour period during July in a headwater stream of the Susquehanna River drainage in central New York. Feeding activity was expressed as the ratio of stomach weight divided by the crayfish wet weight. The diel food consumption patterns of all three size groups of rusty crayfish (i.e., ??? 10 mm, 11-20 mm, and > 20 mm carapace length) were significantly different. Peak feeding of the smallest crayfish occurred during crepuscular periods. Food consumption of the intermediate size crayfish was highest at 2000 h, and feeding of large crayfish was consistently high from 1200 h to 0400 h. Feeding intensity of both small and intermediate size crayfish was highest when feeding intensity of large crayfsh was lowest. Ontogenetic differences in feeding periodicity may be associated with predation pressure from large rusty crayfish on smaller individuals.

Ontogenetic Variation in Food Consumption of Rusty Crayfish (Orconectes rusticus) in a Central New York Stream

USGS Publications Warehouse

Johnson, James H.; Nack, Christopher C.

2010-01-01

We examined feeding periodicity of three size groups of the rusty crayfish (Orconectes rusticus) at four-hour intervals over a 28-hour period during July in a headwater stream of the Susquehanna River drainage in central New York. Feeding activity was expressed as the ratio of stomach weight divided by the crayfish wet weight. The diel food consumption patterns of all three size groups of rusty crayfish (i.e., ≤ 10 mm, 11–20 mm, and > 20 mm carapace length) were significantly different. Peak feeding of the smallest crayfish occurred during crepuscular periods. Food consumption of the intermediate size crayfish was highest at 2000 h, and feeding of large crayfish was consistently high from 1200 h to 0400 h. Feeding intensity of both small and intermediate size crayfish was highest when feeding intensity of large crayfsh was lowest. Ontogenetic differences in feeding periodicity may be associated with predation pressure from large rusty crayfish on smaller individuals.

Density dependence and phenological mismatch: consequences for growth and survival of sub-arctic nesting Canada Geese

USGS Publications Warehouse

Brook, Rodney W.; Leafloor, James O.; Douglas, David C.; Abraham, Kenneth F.

2015-01-01

The extent to which species are plastic in the timing of their reproductive events relative to phenology suggests how change might affect their demography. An ecological mismatch between the timing of hatch for avian species and the peak availability in quality and quantity of forage for rapidly growing offspring might ultimately affect recruitment to the breeding population unless individuals can adjust the timing of breeding to adapt to changing phenology. We evaluated effects of goose density, hatch timing relative to forage plant phenology, and weather indices on annual growth of pre-fledging Canada geese (Branta canadensis) from 1993-2010 at Akimiski Island, Nunavut. We found effects of both density and hatch timing relative to forage plant phenology; the earlier that eggs hatched relative to forage plant phenology, the larger the mean gosling size near fledging. Goslings were smallest in years when hatch was latest relative to forage plant phenology, and when local abundance of breeding adults was highest. We found no evidence for a trend in relative hatch timing, but it was apparent that in early springs, Canada geese tended to hatch later relative to vegetation phenology, suggesting that geese were not always able to adjust the timing of nesting as rapidly as vegetation phenology was advanced. Analyses using forage biomass information revealed a positive relationship between gosling size and per capita biomass availability, suggesting a causal mechanism for the density effect. The effects of weather parameters explained additional variation in mean annual gosling size, although total June and July rainfall had a small additive effect on gosling size. Modelling of annual first year survival probability using mean annual gosling size as an annual covariate revealed a positive relationship, suggesting that reduced gosling growth negatively impacts recruitment.

Effects of vegetation restoration on the aggregate stability and distribution of aggregate-associated organic carbon in a typical karst gorge region

NASA Astrophysics Data System (ADS)

Tang, F. K.; Cui, M.; Lu, Q.; Liu, Y. G.; Guo, H. Y.; Zhou, J. X.

2015-08-01

Changes in soil utilization significantly affect aggregate stability and aggregate-associated soil organic carbon (SOC). A field investigation and indoor analysis were conducted in order to study the soil aggregate stability and organic carbon distribution in the water-stable aggregates (WSA) of the bare land (BL), grassland (GL), shrubland (SL), and woodland (WL) in a typical karst gorge region. The results indicated that the BL, GL, SL, and WL were dominated by particles with sizes > 5 mm under dry sieving treatment, and that the soil aggregate contents of various sizes decreased as the particle size decreased. In addition, the BL, GL, SL, and WL were predominantly comprised of WSA < 0.25 mm under wet sieving treatment, and that the WSA contents initially increased, then decreased, and then increased again as the particle size decreased. Furthermore, at a soil depth of 0-60 cm, the mean weight diameter (MWD), geometrical mean diameter (GMD), and fractal dimensions (D) of the dry aggregates and water-stable aggregates in the different types of land were ranked, in descending order, as WL > GL > SL > BL. The contents of WSA > 0.25 mm, MWD and GMD increased significantly, in that order, and the percentage of aggregate destruction (PAD) and fractal dimensions decreased significantly as the soil aggregate stability improved. The results of this study indicated that, as the SOC contents increased after vegetation restoration, the average SOC content of WL was 2.35, 1.37, and 1.26 times greater than that in the BL, GL, and SL, respectively. The total SOC and SOC associated in WSA of various sizes were the highest at a soil depth of 0-20 cm. In addition, the SOC contents of the WSA increased as the soil aggregate sizes decreased. The SOC contents of the WSA < 0.25 mm were highest except in the bare land, and the SOC contents of the aggregates < 0.25 mm, which ranged from 18.85 to 41.08 %, comprised the majority of the total aggregate SOC contents. The woodland and grassland facilitated WSA stability and SOC protection, thus, promoting the natural restoration of vegetation by reducing artificial disturbances could effectively restore the ecology of and prevent soil erosion in karst regions.

Population dynamics of pond zooplankton, I. Diaptomus pallidus Herrick

USGS Publications Warehouse

Armitage, K.B.; Saxena, B.; Angino, E.E.

1973-01-01

The simultaneous and lag relationships between 27 environmental variables and seven population components of a perennial calanoid copepod were examined by simple and partial correlations and stepwise regression. The analyses consistently explained more than 70% of the variation of a population component. The multiple correlation coefficient (R) usually was highest in no lag or in 3-week or 4-week lag except for clutch size in which R was highest in 1-week lag. Population control, egg-bearing, and clutch size were affected primarily by environmental components categorized as weather; food apparently was relatively minor in affecting population control or reproduction. ?? 1973 Dr. W. Junk B.V. Publishers.

Effects of tool handle dimension and workpiece orientation and size on wrist ulnar/radial torque strength, usability and discomfort in a wrench task.

PubMed

Dianat, Iman; Rahimi, Soleyman; Nedaei, Moein; Asghari Jafarabadi, Mohammad; Oskouei, Ali E

2017-03-01

The effects of tool handle dimension (three modified designs of wrenches with 30-50 mm diameter cylindrical handles and traditional design with rectangular cross-sectional (5 mm × 25 mm) handle), workpiece orientation (vertical/horizontal) and workpiece size (small/large) as well as user's hand size on wrist ulnar/radial (U/R) torque strength, usability and discomfort, and also the relationship between these variables were evaluated in a maximum torque task using wrenches. The highest and lowest levels of maximal wrist U/R torque strength were recorded for the 30 mm diameter handle and traditional wrench design, respectively. The prototype handle with 30 mm diameter, together with 40 mm diameter handle, was also better than other designs as they received higher usability ratings and caused less discomfort. The mean wrist torque strength exerted on a vertically oriented workpiece (in the sagittal plane) was 23.8% higher than that exerted on a horizontally oriented one (in the transverse plane). The user's hand size had no effect on torque exertions. The wrist torque strength and usability were negatively correlated with hand and finger discomfort ratings. The results are also discussed in terms of their implications for hand tool and workstation configuration in torque tasks involving wrenches. Copyright © 2016 Elsevier Ltd. All rights reserved.

Aerosol particles generated by diesel-powered school buses at urban schools as a source of children’s exposure

PubMed Central

Hochstetler, Heather A.; Yermakov, Mikhail; Reponen, Tiina; Ryan, Patrick H.; Grinshpun, Sergey A.

2015-01-01

Various heath effects in children have been associated with exposure to traffic-related particulate matter (PM), including emissions from school buses. In this study, the indoor and outdoor aerosol at four urban elementary schools serviced by diesel-powered school buses was characterized with respect to the particle number concentrations and size distributions as well as the PM2.5 mass concentrations and elemental compositions. It was determined that the presence of school buses significantly affected the outdoor particle size distribution, specifically in the ultrafine fraction. The time-weighted average of the total number concentration measured outside the schools was significantly associated with the bus and the car counts. The concentration increase was consistently observed during the morning drop-off hours and in most of the days during the afternoon pick-up period (although at a lower degree). Outdoor PM2.5 mass concentrations measured at schools ranged from 3.8 to 27.6 µg m−3. The school with the highest number of operating buses exhibited the highest average PM2.5 mass concentration. The outdoor mass concentrations of elemental carbon (EC) and organic carbon (OC) were also highest at the school with the greatest number of buses. Most (47/55) correlations between traffic-related elements identified in the outdoor PM2.5 were significant with elements identified in the indoor PM2.5. Significant associations were observed between indoor and outdoor aerosols for EC, EC/OC, and the total particle number concentration. Day-to-day and school-to-school variations in Indoor/Outdoor (I/O) ratios were related to the observed differences in opening windows and doors, which enhanced the particle penetration, as well as indoor activities at schools. Overall, the results on I/O ratio obtained in this study reflect the sizes of particles emitted by diesel-powered school bus engines (primarily, an ultrafine fraction capable of penetrating indoors). PMID:25904818

Direct and indirect drift assessment means. Part 2: wind tunnel experiments.

PubMed

Nuyttens, D; De Schampheleire, M; Baetens, K; Sonck, B

2008-01-01

Wind tunnel measurements, performed in Silsoe Research Institute (SRI), were used to measure airborne and fallout spray volumes under directly comparable and repeatable conditions for single and static nozzles. Based on these measurements, drift potential reduction percentages (DPRP), expressing the percentage reduction of the drift potential compared with the reference spraying, were calculated following three approaches. The first approach was based on the calculation of the first moment of the airborne spray profile (DPRPv1). In the second and third approach, the surface under the measured airborne (DPRPv2) and fallout (DPRP(H)) deposit curve were used. These DPRP values express the percentage reduction of the drift potential compared with the reference spraying. Ten different spray nozzles were tested. The results showed the expected fallout profiles with the highest deposits closest to the nozzle and a systematic decrease with distance from the nozzle. For the airborne deposit profiles, the highest deposits were found at the Lowest collectors with an important systematic decrease with increasing heights. For the same nozzle size and spray pressure, DPRP values are generally higher for the air inclusion nozzles followed by the low-drift nozzles and the standard flat fan nozzles and the effect of nozzle type is most important for smaller nozzle sizes. In general, the bigger the ISO nozzle size, the higher the DPRP values. Comparing results from the three different approaches namely, DPRPv1, DPRPv2 and DPRP(H), some interesting conclusions can be drawn. For the standard flat fan nozzles, DPRPv1, values were the highest followed by DPRPv2 and DPRP(H) while for the low-drift nozzles opposite results were found. For the air inclusion nozzles, there was a relatively good agreement between DPRPv1, DPRPv1 and DPRP(H) values. All of this is important in the interpretation of wind tunnel data for different nozzle types and sampling methodologies.

Aerosol particles generated by diesel-powered school buses at urban schools as a source of children's exposure

NASA Astrophysics Data System (ADS)

Hochstetler, Heather A.; Yermakov, Mikhail; Reponen, Tiina; Ryan, Patrick H.; Grinshpun, Sergey A.

2011-03-01

Various heath effects in children have been associated with exposure to traffic-related particulate matter (PM), including emissions from school buses. In this study, the indoor and outdoor aerosol at four urban elementary schools serviced by diesel-powered school buses was characterized with respect to the particle number concentrations and size distributions as well as the PM2.5 mass concentrations and elemental compositions. It was determined that the presence of school buses significantly affected the outdoor particle size distribution, specifically in the ultrafine fraction. The time-weighted average of the total number concentration measured outside the schools was significantly associated with the bus and the car counts. The concentration increase was consistently observed during the morning drop-off hours and in most of the days during the afternoon pick-up period (although at a lower degree). Outdoor PM2.5 mass concentrations measured at schools ranged from 3.8 to 27.6 μg m-3. The school with the highest number of operating buses exhibited the highest average PM2.5 mass concentration. The outdoor mass concentrations of elemental carbon (EC) and organic carbon (OC) were also highest at the school with the greatest number of buses. Most (47/55) correlations between traffic-related elements identified in the outdoor PM2.5 were significant with elements identified in the indoor PM2.5. Significant associations were observed between indoor and outdoor aerosols for EC, EC/OC, and the total particle number concentration. Day-to-day and school-to-school variations in Indoor/Outdoor (I/O) ratios were related to the observed differences in opening windows and doors, which enhanced the particle penetration, as well as indoor activities at schools. Overall, the results on I/O ratio obtained in this study reflect the sizes of particles emitted by diesel-powered school bus engines (primarily, an ultrafine fraction capable of penetrating indoors).

Aerosol particles generated by diesel-powered school buses at urban schools as a source of children's exposure.

PubMed

Hochstetler, Heather A; Yermakov, Mikhail; Reponen, Tiina; Ryan, Patrick H; Grinshpun, Sergey A

2011-03-01

Various heath effects in children have been associated with exposure to traffic-related particulate matter (PM), including emissions from school buses. In this study, the indoor and outdoor aerosol at four urban elementary schools serviced by diesel-powered school buses was characterized with respect to the particle number concentrations and size distributions as well as the PM2.5 mass concentrations and elemental compositions. It was determined that the presence of school buses significantly affected the outdoor particle size distribution, specifically in the ultrafine fraction. The time-weighted average of the total number concentration measured outside the schools was significantly associated with the bus and the car counts. The concentration increase was consistently observed during the morning drop-off hours and in most of the days during the afternoon pick-up period (although at a lower degree). Outdoor PM2.5 mass concentrations measured at schools ranged from 3.8 to 27.6 µg m -3 . The school with the highest number of operating buses exhibited the highest average PM2.5 mass concentration. The outdoor mass concentrations of elemental carbon (EC) and organic carbon (OC) were also highest at the school with the greatest number of buses. Most (47/55) correlations between traffic-related elements identified in the outdoor PM2.5 were significant with elements identified in the indoor PM2.5. Significant associations were observed between indoor and outdoor aerosols for EC, EC/OC, and the total particle number concentration. Day-to-day and school-to-school variations in Indoor/Outdoor (I/O) ratios were related to the observed differences in opening windows and doors, which enhanced the particle penetration, as well as indoor activities at schools. Overall, the results on I/O ratio obtained in this study reflect the sizes of particles emitted by diesel-powered school bus engines (primarily, an ultrafine fraction capable of penetrating indoors).

The effects of jury size, evidence complexity, and note taking on jury process and performance in a civil trial.

PubMed

Horowitz, Irwin A; Bordens, Kenneth S

2002-02-01

A total of 567 jury-eligible men and women who were assigned to 6- or 12-person juries saw a videotaped civil trial that contained either I or 4 plaintiffs. Half the juries took notes, whereas the remainder did not. Six-person juries that did not take notes awarded multiple plaintiffs the highest amounts of compensation. Six-person juries also gave the highest punitive damages when they did not take notes and judged multiple plaintiffs. The punitive awards of 6-person juries were highly variable compared with 12-person juries. Multiple plaintiffs also increased the unpredictability of jury punitive awards. Twelve-person juries deliberated longer, recalled more probative information, and relied less than 6-person juries on evaluative statements and nonprobative evidence. Limitations and implications are discussed.

Advanced spacecraft fire safety: Proposed projects and program plan

NASA Technical Reports Server (NTRS)

Youngblood, Wallace W.; Vedha-Nayagam, M.

1989-01-01

A detailed review identifies spacecraft fire safety issues and the efforts for their resolution, particularly for the threats posed by the increased on-orbit duration, size, and complexity of the Space Station Freedom. Suggestions provided by a survey of Wyle consultants and outside fire safety experts were combined into 30 research and engineering projects. The projects were then prioritized with respect to urgency to meet Freedom design goals, status of enabling technology, cost, and so on, to yield 14 highest priority projects, described in terms of background, work breakdown structure, and schedule. These highest priority projects can be grouped into the thematic areas of fire detection, fire extinguishment, risk assessment, toxicology and human effects, and ground based testing. Recommendations for overall program management stress the need for NASA Headquarters and field center coordination, with information exchange through spacecraft fire safety oversight committees.

Maternal investment in reproduction and its consequences in leatherback turtles.

PubMed

Wallace, Bryan P; Sotherland, Paul R; Tomillo, Pilar Santidrian; Reina, Richard D; Spotila, James R; Paladino, Frank V

2007-05-01

Maternal investment in reproduction by oviparous non-avian reptiles is usually limited to pre-ovipositional allocations to the number and size of eggs and clutches, thus making these species good subjects for testing hypotheses of reproductive optimality models. Because leatherback turtles (Dermochelys coriacea) stand out among oviparous amniotes by having the highest clutch frequency and producing the largest mass of eggs per reproductive season, we quantified maternal investment of 146 female leatherbacks over four nesting seasons (2001-2004) and found high inter- and intra-female variation in several reproductive characteristics. Estimated clutch frequency [coefficient of variation (CV) = 31%] and clutch size (CV = 26%) varied more among females than did egg mass (CV = 9%) and hatchling mass (CV = 7%). Moreover, clutch size had an approximately threefold higher effect on clutch mass than did egg mass. These results generally support predictions of reproductive optimality models in which species that lay several, large clutches per reproductive season should exhibit low variation in egg size and instead maximize egg number (clutch frequency and/or size). The number of hatchlings emerging per nest was positively correlated with clutch size, but fraction of eggs in a clutch yielding hatchlings (emergence success) was not correlated with clutch size and varied highly among females. In addition, seasonal fecundity and seasonal hatchling production increased with the frequency and the size of clutches (in order of effect size). Our results demonstrate that female leatherbacks exhibit high phenotypic variation in reproductive traits, possibly in response to environmental variability and/or resulting from genotypic variability within the population. Furthermore, high seasonal and lifetime fecundity of leatherbacks probably reflect compensation for high and unpredictable mortality during early life history stages in this species.

The comparative evidence basis for the efficacy of second-generation antidepressants in the treatment of depression in the US: A Bayesian meta-analysis of Food and Drug Administration reviews.

PubMed

Monden, Rei; Roest, Annelieke M; van Ravenzwaaij, Don; Wagenmakers, Eric-Jan; Morey, Richard; Wardenaar, Klaas J; de Jonge, Peter

2018-08-01

Studies have shown similar efficacy of different antidepressants in the treatment of depression. Data of phase-2 and -3 clinical-trials for 16 antidepressants (levomilnacipran, desvenlafaxine, duloxetine, venlafaxine, paroxetine, escitalopram, vortioxetine, mirtazapine, venlafaxine XR, sertraline, fluoxetine, citalopram, paroxetine CR, nefazodone, bupropion, vilazodone), approved by the FDA for the treatment of depression between 1987 and 2016, were extracted from the FDA reviews that were used to evaluate efficacy prior to marketing approval, which are less liable to reporting biases. Meta-analytic Bayes factors, which quantify the strength of evidence for efficacy, were calculated. In addition, posterior pooled effect-sizes were calculated and compared with classical estimations. The resulted Bayes factors showed that the evidence load for efficacy varied strongly across antidepressants. However, all tested drugs except for bupropion and vilazodone showed strong evidence for their efficacy. The posterior effect-size distributions showed variation across antidepressants, with the highest pooled estimated effect size for venlafaxine followed by paroxetine, and the lowest for bupropion and vilazodone. Not all published trials were included in the study. The results illustrate the importance of considering both the effect size and the evidence-load when judging the efficacy of a treatment. In doing so, the currently employed Bayesian approach provided clear insights on top of those gained with traditional approaches. Copyright © 2018 Elsevier B.V. All rights reserved.

Effect of iron particle size and volume fraction on the magnetic properties of Fe/silicate glass soft magnetic composites

NASA Astrophysics Data System (ADS)

Ding, Wei; Jiang, Longtao; Liao, Yaqin; Song, Jiabin; Li, Bingqing; Wu, Gaohui

2015-03-01

Fe/silicate glass soft magnetic composites (SMC) were fabricated by powder metallurgy with 1000 MPa pressure at room temperature, and then annealed at 700 °C for 90 min. The iron particles distributed uniformly in the composites, and have been separated from each other by a continuous silicate glass insulating layer. Fe/glass interface was well bonded and a quasi-continuous layer Fe3O4 and FeO exited. Very fine crystalline phases Na12Ca3Fe2(Si6O18)2 were formed in silicate glass. Composite containing 57 vol% 75 μm iron particles demonstrated highest resistivity of 7.8×10-3 Ω m. The μm, Bs and Bt increased while Hc of Fe/silicate glass composites decreased with the increase of average size of iron particles. The composite with highest amount (82 vol%) and largest average size (140 μm) of iron particles demonstrated best μm, Bs and Bt and Hc, which were 622, 1.57 T, 1.43 T, 278 A/m, respectively. The composite containing 57 vol% 75 μm iron particles demonstrated minimum core loss of 3.5 W/kg at 50 Hz and 28.1 W/kg at 400 Hz, while the composite containing 82 vol% 140 μm iron particles exhibited maximum core loss of 5.2 W/kg at 50 Hz and 67.7 W/kg at 400 Hz.

In vitro toxicity of different-sized ZnO nanoparticles in Caco-2 cells

NASA Astrophysics Data System (ADS)

Kang, Tianshu; Guan, Rongfa; Chen, Xiaoqiang; Song, Yijuan; Jiang, Han; Zhao, Jin

2013-11-01

There has been rapid growth in nanotechnology in both the public and private sectors worldwide, but concern about nanosafety exists. To assess size-dependent cytotoxicity on human cancer cells, we studied the cytotoxic effect of three kinds of zinc oxide nanoparticles (ZnO NPs) on human epithelial colorectal adenocarcinoma (Caco-2) cells. Nanoparticles were first characterized by size, distribution, and intensity. Multiple assays have been adopted to measure the cell activity and oxidative stress. The cytotoxicity of ZnO NPs was time dependent and dose dependent. The 24-h exposure was chosen to confirm the viability and accessibility of the cells and taken as the appropriate time for the following test system. The IC50 value was found at a low concentration. The oxidative stress elicited a significant reduction in glutathione with increase in reactive oxygen species and lactate dehydrogenase. The toxicity resulted in a deletion of cells in the G1 phase and an accumulation of cells in the S and G2/M phases. One type of metallic oxide (ZnO) exerted different cytotoxic effects according to different particle sizes. Data from the previous experiments showed that 26-nm ZnO NPs appeared to have the highest toxicity to Caco-2 cells. The study demonstrated the toxicity of ZnO NPs to Caco-2 cells and the impact of particle size, which could be useful in the medical applications.

Exploring molecular sieve capabilities of activated carbon fibers to reduce the impact of NOM preloading on trichloroethylene adsorption

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

Tanju Karanfil; Seyed A. Dastgheib; Dina Mauldin

2006-02-15

Adsorption of trichloroethylene (TCE) by two activated carbon fibers ACF10 and ACF20H and two granular activated carbons, coal-based F400 and Macro preloaded with hydrophobic and transphilic fractions of natural organic matter (NOM) was examined. ACF10, the most microporous activated carbon used in this study, had over 90% of its pore volume in pores smaller than 10 {angstrom}. It also had the highest volume in pores 5-8 {angstrom}, which is the optimum pore size region for TCE adsorption, among the four activated carbons. Adsorption of NOM fractions by ACF10 was, in general, negligible. Therefore, ACF10, functioning as a molecular sieve duringmore » preloading, exhibited the least NOM uptake for each fraction, and subsequently the highest TCE adsorption. The other three sorbents had wider pore size distributions, including high volumes in pores larger than 10 {angstrom}, where NOM molecules can adsorb. As a result, they showed a higher degree of uptake for all NOM fractions, and subsequently lower adsorption capacities for TCE, as compared to ACF10. The results obtained in this study showed that understanding the interplay between the optimum pore size region for the adsorption of target synthetic organic contaminant (SOC) and the pore size region for the adsorption of NOM molecules is important for controlling NOM-SOC competitions. Experiments with different NOM fractions indicated that the degree of NOM loading is important in terms of preloading effects; however the way that the carbon pores are filled and loaded by different NOM fractions can be different and may create an additional negative impact on TCE adsorption. 40 refs., 3 figs., 2 tabs.« less

Characterization of distinct Arctic aerosol accumulation modes and their sources

NASA Astrophysics Data System (ADS)

Lange, R.; Dall'Osto, M.; Skov, H.; Nøjgaard, J. K.; Nielsen, I. E.; Beddows, D. C. S.; Simo, R.; Harrison, R. M.; Massling, A.

2018-06-01

In this work we use cluster analysis of long term particle size distribution data to expand an array of different shorter term atmospheric measurements, thereby gaining insights into longer term patterns and properties of Arctic aerosol. Measurements of aerosol number size distributions (9-915 nm) were conducted at Villum Research Station (VRS), Station Nord in North Greenland during a 5 year record (2012-2016). Alongside this, measurements of aerosol composition, meteorological parameters, gaseous compounds and cloud condensation nuclei (CCN) activity were performed during different shorter occasions. K-means clustering analysis of particle number size distributions on daily basis identified several clusters. Clusters of accumulation mode aerosols (main size modes > 100 nm) accounted for 56% of the total aerosol during the sampling period (89-91% during February-April, 1-3% during June-August). By association to chemical composition, cloud condensation nuclei properties, and meteorological variables, three typical accumulation mode aerosol clusters were identified: Haze (32% of the time), Bimodal (14%) and Aged (6%). In brief: (1) Haze accumulation mode aerosol shows a single mode at 150 nm, peaking in February-April, with highest loadings of sulfate and black carbon concentrations. (2) Accumulation mode Bimodal aerosol shows two modes, at 38 nm and 150 nm, peaking in June-August, with the highest ratio of organics to sulfate concentrations. (3) Aged accumulation mode aerosol shows a single mode at 213 nm, peaking in September-October and is associated with cloudy and humid weather conditions during autumn. The three aerosol clusters were considered alongside CCN concentrations. We suggest that organic compounds, that are likely marine biogenic in nature, greatly influence the Bimodal cluster and contribute significantly to its CCN activity. This stresses the importance of better characterizing the marine ecosystem and the aerosol-mediated climate effects in the Arctic.

Optimal control of Atlantic population Canada geese

USGS Publications Warehouse

Hauser, C.E.; Runge, M.C.; Cooch, E.G.; Johnson, F.A.; Harvey, W.F.

2007-01-01

Management of Canada geese (Branta canadensis) can be a balance between providing sustained harvest opportunity while not allowing populations to become overabundant and cause damage. In this paper, we focus on the Atlantic population of Canada geese and use stochastic dynamic programming to determine the optimal harvest strategy over a range of plausible models for population dynamics. There is evidence to suggest that the population exhibits significant age structure, and it is possible to reconstruct age structure from surveys. Consequently the harvest strategy is a function of the age composition, as well as the abundance, of the population. The objective is to maximize harvest while maintaining the number of breeding adults in the population between specified upper and lower limits. In addition, the total harvest capacity is limited and there is uncertainty about the strength of density-dependence. We find that under a density-independent model, harvest is maximized by maintaining the breeding population at the highest acceptable abundance. However if harvest capacity is limited, then the optimal long-term breeding population size is lower than the highest acceptable level, to reduce the risk of the population growing to an unacceptably large size. Under the proposed density-dependent model, harvest is maximized by maintaining the breeding population at an intermediate level between the bounds on acceptable population size; limits to harvest capacity have little effect on the optimal long-term population size. It is clear that the strength of density-dependence and constraints on harvest significantly affect the optimal harvest strategy for this population. Model discrimination might be achieved in the long term, while continuing to meet management goals, by adopting an adaptive management strategy.

Food resource effects on diel movements and body size of cisco in north-temperate lakes.

PubMed

Ahrenstorff, Tyler D; Hrabik, Thomas R; Jacobson, Peter C; Pereira, Donald L

2013-12-01

The movement patterns and body size of fishes are influenced by a host of physical and biological conditions, including temperature and oxygen, prey densities and foraging potential, growth optimization, and predation risk. Our objectives were to (1) investigate variability in vertical movement patterns of cisco (Coregonus artedi) in a variety of inland lakes using hydroacoustics, (2) explore the causal mechanisms influencing movements through the use of temperature/oxygen, foraging, growth, and predation risk models, and (3) examine factors that may contribute to variations in cisco body size by considering all available information. Our results show that cisco vertical movements vary substantially, with different populations performing normal diel vertical migrations (DVM), no DVM, and reverse DVM in lakes throughout Minnesota and northern Wisconsin, USA. Cisco populations with the smallest body size were found in lakes with lower zooplankton densities. These smaller fish showed movements to areas of highest foraging or growth potential during the day and night, despite moving out of preferred temperature and oxygen conditions and into areas of highest predation risk. In lakes with higher zooplankton densities, cisco grew larger and had movements more consistent with behavioral thermoregulation and predator avoidance, while remaining in areas with less than maximum foraging and growth potential. Furthermore, the composition of potential prey items present in each lake was also important. Cisco that performed reverse DVM consumed mostly copepods and cladocerans, while cisco that exhibited normal DVM or no migration consumed proportionally more macro-zooplankton species. Overall, our results show previously undocumented variation in migration patterns of a fish species, the mechanisms underlying those movements, and the potential impact on their growth potential.

Do marine phytoplankton follow Bergmann's rule sensu lato?

PubMed

Sommer, Ulrich; Peter, Kalista H; Genitsaris, Savvas; Moustaka-Gouni, Maria

2017-05-01

Global warming has revitalized interest in the relationship between body size and temperature, proposed by Bergmann's rule 150 years ago, one of the oldest manifestations of a 'biogeography of traits'. We review biogeographic evidence, results from clonal cultures and recent micro- and mesocosm experiments with naturally mixed phytoplankton communities regarding the response of phytoplankton body size to temperature, either as a single factor or in combination with other factors such as grazing, nutrient limitation, and ocean acidification. Where possible, we also focus on the comparison between intraspecific size shifts and size shifts resulting from changes in species composition. Taken together, biogeographic evidence, community-level experiments and single-species experiments indicate that phytoplankton average cell sizes tend to become smaller in warmer waters, although temperature is not necessarily the proximate environmental factor driving size shifts. Indirect effects via nutrient supply and grazing are important and often dominate. In a substantial proportion of field studies, resource availability is seen as the only factor of relevance. Interspecific size effects are greater than intraspecific effects. Direct temperature effects tend to be exacerbated by indirect ones, if warming leads to intensified nutrient limitation or copepod grazing while ocean acidification tends to counteract the temperature effect on cell size in non-calcifying phytoplankton. We discuss the implications of the temperature-related size trends in a global-warming context, based on known functional traits associated with phytoplankton size. These are a higher affinity for nutrients of smaller cells, highest maximal growth rates of moderately small phytoplankton (ca. 10 2  µm 3 ), size-related sensitivities for different types of grazers, and impacts on sinking rates. For a phytoplankton community increasingly dominated by smaller algae we predict that: (i) a higher proportion of primary production will be respired within the microbial food web; (ii) a smaller share of primary production will be channeled to the classic phytoplankton - crustacean zooplankton - fish food chain, thus leading to decreased ecological efficiency from a fish-production point of view; (iii) a smaller share of primary production will be exported through sedimentation, thus leading to decreased efficiency of the biological carbon pump. © 2016 The Authors. Biological Reviews published by John Wiley & Sons Ltd on behalf of Cambridge Philosophical Society.

Numerical modeling of nanodrug distribution in tumors with heterogeneous vasculature.

PubMed

Chou, Cheng-Ying; Chang, Wan-I; Horng, Tzyy-Leng; Lin, Win-Li

2017-01-01

The distribution and accumulation of nanoparticle dosage in a tumor are important in evaluating the effectiveness of cancer treatment. The cell survival rate can quantify the therapeutic effect, and the survival rates after multiple treatments are helpful to evaluate the efficacy of a chemotherapy plan. We developed a mathematical tumor model based on the governing equations describing the fluid flow and particle transport to investigate the drug transportation in a tumor and computed the resulting cumulative concentrations. The cell survival rate was calculated based on the cumulative concentration. The model was applied to a subcutaneous tumor with heterogeneous vascular distributions. Various sized dextrans and doxorubicin were respectively chosen as the nanodrug carrier and the traditional chemotherapeutic agent for comparison. The results showed that: 1) the largest nanoparticle drug in the current simulations yielded the highest cumulative concentration in the well vascular region, but second lowest in the surrounding normal tissues, which implies it has the best therapeutic effect to tumor and at the same time little harmful to normal tissue; 2) on the contrary, molecular chemotherapeutic agent produced the second lowest cumulative concentration in the well vascular tumor region, but highest in the surrounding normal tissue; 3) all drugs have very small cumulative concentrations in the tumor necrotic region, where drug transport is solely through diffusion. This might mean that it is hard to kill tumor stem cells hiding in it. The current model indicated that the effectiveness of the anti-tumor drug delivery was determined by the interplay of the vascular density and nanoparticle size, which governs the drug transport properties. The use of nanoparticles as anti-tumor drug carriers is generally a better choice than molecular chemotherapeutic agent because of its high treatment efficiency on tumor cells and less damage to normal tissues.

Effect of compositions in nanostructured lipid carriers (NLC) on skin hydration and occlusion.

PubMed

Loo, Ch; Basri, M; Ismail, R; Lau, Hln; Tejo, Ba; Kanthimathi, Ms; Hassan, Ha; Choo, Ym

2013-01-01

To study the effects of varying lipid concentrations, lipid and oil ratio, and the addition of propylene glycol and lecithin on the long-term physical stability of nanostructured lipid nanocarriers (NLC), skin hydration, and transepidermal water loss. The various NLC formulations (A1-A5) were prepared and their particle size, zeta potential, viscosity, and stability were analyzed. The formulations were applied on the forearms of the 20 female volunteers (one forearm of each volunteer was left untreated as a control). The subjects stayed for 30 minutes in a conditioned room with their forearms uncovered to let the skin adapt to the temperature (22°C ± 2°C) and humidity (50% ± 2%) of the room. Skin hydration and skin occlusion were recorded at day one (before treatment) and day seven (after treatment). Three measurements for skin hydration and skin occlusion were performed in each testing area. NLC formulations with the highest lipid concentration, highest solid lipid concentration, and additional propylene glycol (formulations A1, A2, and A5) showed higher physical stability than other formulations. The addition of propylene glycol into an NLC system helped to reduce the particle size of the NLC and enhanced its long-term physical stability. All the NLC formulations were found to significantly increase skin hydration compared to the untreated controls within 7 days. All NLC formulations exhibited occlusive properties as they reduced the transepidermal water loss within 7 days. This effect was more pronounced with the addition of propylene glycol or lecithin into an NLC formulation, whereby at least 60% reduction in transepidermal water loss was observed. NLCs with high lipid content, solid lipid content, phospholipid, and lecithin are a highly effective cosmetic delivery system for cosmetic topical applications that are designed to boost skin hydration.

Variation of radiation level and radionuclide enrichment in high background area.

PubMed

Shetty, P K; Narayana, Y

2010-12-01

Significantly high radiation level and radionuclide concentration along Quilon beach area of coastal Kerala have been reported by several investigators. Detailed gamma radiation level survey was carried out using a portable scintillometer. Detailed studies on radionuclides concentration in different environmental matrices of high background areas were undertaken in the coastal areas of Karunagapalli, Kayankulam, Chavara, Neendakara and Kollam to study the distribution and enrichment of the radionuclides in the region. The absorbed gamma dose rates in air in high background area are in the range 43-17,400nGyh⁻¹. Gamma radiation level is found to be maximum at a distance of 20m from the sea waterline in all beaches. The soil samples collected from different locations were analysed for primordial radionuclides by gamma spectrometry. The activity of primordial radionuclides was determined for the different size fractions of soil to study the enrichment pattern. The highest activity of (232)Th and (226)Ra was found to be enriched in 125-63μ size fraction. The preferential accumulation of (40)K was found in <63μ fraction. The minimum (232)Th activity was 30.2Bqkg⁻¹, found in 1000-500μ particle size fraction at Kollam and maximum activity of 3250.4Bqkg⁻¹ was observed in grains of size 125-63μ at Neendakara. The lowest (226)Ra activity observed was 33.9Bqkg⁻¹ at Neendakara in grains of size 1000-500μ and the highest activity observed was 482.6Bqkg⁻¹ in grains of size 125-63μ in Neendakara. The highest (40)K activity found was 1923Bqkg⁻¹ in grains of size <63μ for a sample collected from Neendakara. A good correlation was observed between computed dose and measured dose in air. The correlation between (232)Th and (226)Ra was also moderately high. The results of these investigations are presented and discussed in this paper. Copyright © 2010 Elsevier Ltd. All rights reserved.

A comparison of tumour size measurements with palpation, ultrasound and mammography in male breast cancer: first results of the prospective register study.

PubMed

Streng, Martin; Ignatov, Atanas; Reinisch, Mattea; Costa, Serban-Dan; Eggemann, Holm

2018-02-01

Precise presurgical diagnosis of tumour size is essential for adequate treatment of male breast cancer (MBC). This study is aimed to compare the accuracy of clinical measurement (CE), ultrasound (US) and mammography (MG) for preoperative estimation of tumour size. This study was conducted as a prospective, multicentre register study. One hundred and twenty-nine male patients with invasive breast cancer were included. CE, US and MG were performed in 107, 110 and 75 patients, respectively, and the estimated tumour size was compared with the histopathological (HP) tumour size. All methods tended to underestimate the HP tumour size. None of the methods were significantly more accurate than the others in determining the maximal tumour diameter. The sensitivity within 5 mm tolerance for US was 65.5%, which was better than for MG (61.3%) and CE (56.6%). In the group of patients with pT2 tumours, MG showed significantly better accuracy than US. The measurements obtained with each method were significantly correlated with the HP measurements. The highest correlation coefficient was observed for MG (0.788), followed by US (0.741) and CE (0.671). Our data demonstrate that MG and US have similar accuracy with regard to tumour size estimation. US assessment showed the highest sensitivity in determining tumour size, followed by MG and CE. However, MG demonstrated a significant advantage for estimating the real tumour size for pT2 tumours compared to US or CE.

Grain size effect on the electrical and magneto-transport properties of nanosized Pr0.67Sr0.33MnO3

NASA Astrophysics Data System (ADS)

Ng, S. W.; Lim, K. P.; Halim, S. A.; Jumiah, H.

2018-06-01

In this study, nanosized of Pr0.67Sr0.33MnO3 prepared via sol-gel method followed by heat treatment at 600-1000 °C in intervals of 100 °C were synthesized. The structure, surface morphology, electrical, magneto-transport and magnetic properties of the samples were investigated. Rietveld refinements of X-ray diffraction patterns confirm that single phase orthorhombic crystal structure with the space group of Pnma (62) is formed at 600 °C. A strong dependence of surface morphology, electrical and magneto-transport properties on grain size have been observed in this manganites system. Both grain size and crystallite size are increases with the sintering temperature due to the congregation effect. Upon increasing grain size, the paramagnetic-ferromagnetic transition temperature increases from 278 K to 295 K. The resistivity drops and the metal-insulator transition temperature shifted from 184 K to 248 K with increases of grain size due to the grain growth and reduction of grain boundary. Below metal-insulator transition temperature, the samples fit well to the combination of resistivity due to grain or domain boundaries, electron-electron scattering process and electron-phonon interaction. The resistivity data above the metal-insulator transition temperature is well described using small polaron hopping and variable range hopping models. It is found that the negative magnetoresistance also increases with larger grain size where the highest %MR of - 26% can be observed for sample sintered at 1000 °C (245 nm).

Effect of chromatographic conditions and plasmid DNA size on the dynamic binding capacity of a monolithic support.

PubMed

Bicho, Diana; Sousa, Ângela; Sousa, Fani; Queiroz, João; Tomaz, Cãndida

2014-09-01

DNA therapies are becoming recognized alternatives for the treatment and prevention of severe pathologies. Although most current trials have used plasmids <10 kbp, in the future larger plasmids would be required. The purpose of this work was to study the chromatographic behavior of nongrafted carbonyldiimidazole monolithic disks using plasmids with different sizes under hydrophobic conditions. Thereunto, the purification of several plasmids was performed. Higher size plasmids needed lower ammonium sulfate concentration, due to the greater number of interactions between the plasmids and monolith. The dynamic binding capacity experiments for the different plasmids revealed a lower capacity for bigger plasmids. It was also verified that the increase of salt concentration from 2.5 to 3 M of ammonium sulfate increased the capacity. At the highest salt concentration, a slight improvement in the capacity using lower flow rate was observed, possibly due to compaction of plasmid molecules and its better organization on the monolith channels. Finally, a low pH also had a positive effect on the capacity. So, this monolithic support proved to be appropriate to purify the supercoiled isoform of different plasmids with different sizes, providing a valuable instrument as a purification technique. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Annealing Effects on the Formation of Copper Oxide Thin Films

NASA Astrophysics Data System (ADS)

Marzuki, Marina; Zamzuri Mohamad Zain, Mohd; Zarul Hisham, Nurazhra; Zainon, Nooraizedfiza; Harun, Azmi; Nani Ahmad, Rozie

2018-03-01

This study approached the simple method of developing CuO thin films by thermal oxidation on pure Cu sheets. The effects of annealing temperature on the formation of CuO layers have been investigated. The oxide layers have been fabricated by annealing of Cu sheets for 5 hours at different temperatures of 980 ~ 1010 °C. The morphologies and optical properties of annealed Cu sheets were studied by using SEM and UV-Vis spectrophotometer respectively. It is revealed that the annealing temperature influence the grain growth and the grain size increases as the temperature increase. The highest grain size was observed on sample annealed at 1000 °C with average area per grain size of 0.023 mm2. Theoretically, larger grain size provides less barriers for electron mobility and increase the efficiency of solar devices. The optical absorption spectra of the oxide films was also measured. Interference pattern was noted at wavelength about 900 nm corresponding to the formation of CuO film. The interference noise observed could be due to the coarse surface and the presence of powdery oxide deposits that causes the scattering loses from the surface. CuO film obtained by this method may be further studied and exploited as low cost photovoltaic device.

Effect of field view size and lighting on unique-hue selection using Natural Color System object colors.

PubMed

Shamey, Renzo; Zubair, Muhammad; Cheema, Hammad

2015-08-01

The aim of this study was twofold, first to determine the effect of field view size and second of illumination conditions on the selection of unique hue samples (UHs: R, Y, G and B) from two rotatable trays, each containing forty highly chromatic Natural Color System (NCS) samples, on one tray corresponding to 1.4° and on the other to 5.7° field of view size. UH selections were made by 25 color-normal observers who repeated assessments three times with a gap of at least 24h between trials. Observers separately assessed UHs under four illumination conditions simulating illuminants D65, A, F2 and F11. An apparent hue shift (statistically significant for UR) was noted for UH selections at 5.7° field of view compared to those at 1.4°. Observers' overall variability was found to be higher for UH stimuli selections at the larger field of view. Intra-observer variability was found to be approximately 18.7% of inter-observer variability in selection of samples for both sample sizes. The highest intra-observer variability was under simulated illuminant D65, followed by A, F11, and F2. Copyright © 2015 Elsevier Ltd. All rights reserved.

76 FR 28786 - Proposed Data Collections Submitted for Public Comment and Recommendations

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-18

.... The sample size is based on recommendations related to qualitative interview methods and the research... than 10 employees (CPWR, 2007), and this establishment size experiences the highest fatality rate... out occupational safety and health training. This interview will be administered to a sample of...

76 FR 44590 - Agency Forms Undergoing Paperwork Reduction Act Review

Federal Register 2010, 2011, 2012, 2013, 2014

2011-07-26

... health training. This interview will be administered to a sample of approximately 30 owners of construction businesses with 10 or fewer employees from the Greater Cincinnati area. The sample size is based... size experiences the highest fatality rate within construction (U.S. Dept. of Labor, 2008). The need...

The role of event water, a rapid shallow flow component, and catchment size in summer stormflow

USGS Publications Warehouse

Brown, V.A.; McDonnell, Jeffery J.; Burns, Douglas A.; Kendall, C.

1999-01-01

Seven nested headwater catchments (8 to 161 ha) were monitored during five summer rain events to evaluate storm runoff components and the effect of catchment size on water sources. Two-component isotopic hydrograph separation showed that event-water contributions near the time of peakflow ranged from 49% to 62% in the 7 catchments during the highest intensity event. The proportion of event water in stormflow was greater than could be accounted for by direct precipitation onto saturated areas. DOC concentrations in stormflow were strongly correlated with stream 18O composition. Bivariate mixing diagrams indicated that the large event water contributions were likely derived from flow through the soil O-horizon. Results from two-tracer, three-component hydrograph separations showed that the throughfall and O-horizon soil-water components together could account for the estimated contributions of event water to stormflow. End-member mixing analysis confirmed these results. Estimated event-water contributions were inversely related to catchment size, but the relation was significant for only the event with greatest rainfall intensity. Our results suggest that perched, shallow subsurface flow provides a substantial contribution to summer stormflow in these small catchments, but the relative contribution of this component decreases with catchment size.Seven nested headwater catchments (8 to 161 ha) were monitored during five summer rain events to evaluate storm runoff components and the effect of catchment size on water sources. Two-component isotopic hydrograph separation showed that event-water contributions near the time of peakflow ranged from 49% to 62% in the 7 catchments during the highest intensity event. The proportion of event water in stormflow was greater than could be accounted for by direct precipitation onto saturated areas. DOC concentrations in stormflow were strongly correlated with stream 18O composition. Bivariate mixing diagrams indicated that the large event water contributions were likely derived from flow through the soil O-horizon. Results from two-tracer, three-component hydrograph separations showed that the throughfall and O-horizon soil-water components together could account for the estimated contributions of event water to stormflow. End-member mixing analysis confirmed these results. Estimated event-water contributions were inversely related to catchment size, but the relation was significant for only the event with greatest rainfall intensity. Our results suggest that perched, shallow subsurface flow provides a substantial contribution to summer stormflow in these small catchments, but the relative contribution of this component decreases with catchment size.

Carbon nanotube scaffolds with controlled porosity as electromagnetic absorbing materials in the gigahertz range.

PubMed

González, M; Crespo, M; Baselga, J; Pozuelo, J

2016-05-19

Control of the microscopic structure of CNT nanocomposites allows modulation of the electromagnetic shielding in the gigahertz range. The porosity of CNT scaffolds has been controlled by two freezing protocols and a subsequent lyophilization step: fast freezing in liquid nitrogen and slow freezing at -20 °C. Mercury porosimetry shows that slowly frozen specimens present a more open pore size (100-150 μm) with a narrow distribution whereas specimens frozen rapidly show a smaller pore size and a heterogeneous distribution. 3D-scaffolds containing 3, 4, 6 and 7% CNT were infiltrated with epoxy and specimens with 2, 5 and 8 mm thicknesses were characterized in the GHz range. Samples with the highest pore size and porosity presented the lowest reflected power (about 30%) and the highest absorbed power (about 70%), which allows considering them as electromagnetic radiation absorbing materials.

Optimisation of sewage sludge anaerobic digestion through co-digestion with OFMSW: Effect of collection system and particle size

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

Silvestre, Gracia; Ainia, Departamento de Medio Ambiente, Bioenergía e Higiene Industrial, Paterna, Valencia; Bonmatí, August

2015-09-15

Highlights: • Methane production rate increased between 56% and 208% during OFMSW–SS codigestion. • The OFMSW particle size reduction from 20 to 8 mm did not affect the methane yield. • OFMSW–SS codigestion promoted β-oxidation and acetoclastic methanogenic activity. • The evolution of specific activity was a feasible tool to control the process. - Abstract: The effect of organic fraction of municipal solid waste (OFMSW) loading rate and particulate size on the sewage sludge (SS) mesophilic anaerobic co-digestion was assessed in continuous stirred tank reactor at hydraulic retention time of 20 days. The SS–OFMSW mixture composed by 54% of themore » volatile solids fed (inlet-VS), at OLR of 3.1 kg{sub COD} m{sup −3} d{sup −1} (1.9 kg{sub VS} m{sup −3} d{sup −1}), showed the highest increment on the volumetric methane production and yield of +200% and +59% respectively, under stable conditions. The effect of particulate size was assessed with the same mixture and same operational conditions but reducing the OFMSW particulate size from 20 mm to 8 mm with the aim to improve the hydrolysis step, but the results showed any influence in the OFMSW particulate size range analysed. In addition, specific biomass activity was assessed at the end of each co-digestion period. Results showed that OFMSW promoted β-oxidation syntrophic acetogens and the acetoclastic methanogens activity; although the last increase of the OFMSW percentage (from 47% to 54% inlet-VS) affected negatively the specific substrate activity, but not inhibitory effect was observed. Therefore, the results obtained in the continuous experiment could be related with some inhibitory or toxic effect and not due to hydrolysis limitation. The specific biomass activity test was demonstrated to be an interesting tool to evaluate and control the co-digestion process, especially when conventional parameters did not explain the behaviour of the biological system.« less

Structural, magnetic, optical, dielectric, electrical and modulus spectroscopic characteristics of ZnFe2O4 spinel ferrite nanoparticles synthesized via honey-mediated sol-gel combustion method

NASA Astrophysics Data System (ADS)

Yadav, Raghvendra Singh; Kuřitka, Ivo; Vilcakova, Jarmila; Urbánek, Pavel; Machovsky, Michal; Masař, Milan; Holek, Martin

2017-11-01

This paper reports a honey-mediated green synthesis of ZnFe2O4 spinel ferrite nanoparticles and the effect of further annealing on structural, magnetic, optical, dielectric and electrical properties. X-ray diffraction study confirmed the well formation of ZnFe2O4 spinel ferrite crystal structure. Raman and Fourier transform infrared spectroscopy confirmed the formation of spinel ferrite crystal structure. The scanning electron microscopy study revealed the formation of spherical morphology at lower annealing temperature with achieved particle size 30-60 nm, whereas, octahedral like morphology at higher annealing temperature with particle size 50-400 nm. Magnetization measurements were carried out using a vibrating sample magnetometer at room temperature. The estimated magnetic parameter such as saturation magnetization (Ms), remanence (Mr) and coercivity (Hc) showed variation in value with nano-crystallite size. The highest saturation magnetization (Ms) was 12.81 emu/g for as-synthesized ZnFe2O4 spinel ferrite nanoparticles, whereas, highest coercivity (Hc) was 25.77 Oe for ZnFe2O4 nanoparticles annealed at high temperature 1000 °C. UV-Visible reflectance spectroscopy showed the band gap variation from 1.90 eV to 2.14 eV with the increase of annealing temperature. The dielectric constant and dielectric loss were decreased with frequency showing the normal behavior of spinel ferrites. The variation in conductivity is explained in terms of the variation in microstructure and variation in the mobility of charge carriers associated with the cation redistribution induced by annealing or grain size. The modulus and impedance spectroscopy study revealed the influence of bulk grain and the grain boundary on the electrical resistance and capacitance of ZnFe2O4 nanoparticles. The results presented in this work are helpful for green synthesis of well-controlled size, morphology and physical properties of ZnFe2O4 nanoparticles.

Self-pollination rate and floral-display size in Asclepias syriaca (Common Milkweed) with regard to floral-visitor taxa.

PubMed

Howard, Aaron F; Barrows, Edward M

2014-06-23

Animals fertilize thousands of angiosperm species whose floral-display sizes can significantly influence pollinator behavior and plant reproductive success. Many studies have measured the interactions among pollinator behavior, floral-display size, and plant reproductive success, but few studies have been able to separate the effects of pollinator behavior and post-pollination processes on angiosperm sexual reproduction. In this study, we utilized the highly self-incompatible pollinium-pollination system of Asclepias syriaca (Common Milkweed) to quantify how insect visitors influenced male reproductive success measured as pollen removal, female reproductive success measured as pollen deposition, and self-pollination rate. We also determined how floral-display size impacts both visitor behavior and self-pollination rate. Four insect taxonomic orders visited A. syriaca: Coleoptera, Diptera, Hymenoptera, and Lepidoptera. We focused on three groups of visitor taxa within two orders (Hymenoptera and Lepidoptera) with sample sizes large enough for quantitative analysis: Apis mellifera (Western Honey Bee), Bombus spp. (bumble bees) and lepidopterans (butterflies and moths). Qualitatively, lepidopterans had the highest pollinator importance values, but the large variability in the lepidopteran data precluded meaningful interpretation of much of their behavior. The introduced A. mellifera was the most effective and most important diurnal pollinator with regard to both pollen removal and pollen deposition. However, when considering the self-incompatibility of A. syriaca, A. mellifera was not the most important pollinator because of its high self-pollination rate as compared to Bombus spp. Additionally, the rate of self-pollination increased more rapidly with the number of flowers per inflorescence in A. mellifera than in the native Bombus spp. Apis mellifera's high rate of self-pollination may have significant negative effects on both male and female reproductive successes in A. syriaca, causing different selection on floral-display size than native pollinators.

The Effects of Specimen Geometry and Size on the Dynamic Failure of Aluminum Alloy 2219-T8 Under Impact Loading

NASA Astrophysics Data System (ADS)

Bolling, Denzell Tamarcus

A significant amount of research has been devoted to the characterization of new engineering materials. Searching for new alloys which may improve weight, ultimate strength, or fatigue life are just a few of the reasons why researchers study different materials. In support of that mission this study focuses on the effects of specimen geometry and size on the dynamic failure of AA2219 aluminum alloy subjected to impact loading. Using the Split Hopkinson Pressure Bar (SHPB) system different geometric samples including cubic, rectangular, cylindrical, and frustum samples are loaded at different strain rates ranging from 1000s-1 to 6000s-1. The deformation properties, including the potential for the formation of adiabatic shear bands, of the different geometries are compared. Overall the cubic geometry achieves the highest critical strain and the maximum stress values at low strain rates and the rectangular geometry has the highest critical strain and the maximum stress at high strain rates. The frustum geometry type consistently achieves the lowest the maximum stress value compared to the other geometries under equal strain rates. All sample types clearly indicated susceptibility to strain localization at different locations within the sample geometry. Micrograph analysis indicated that adiabatic shear band geometry was influenced by sample geometry, and that specimens with a circular cross section are more susceptible to shear band formation than specimens with a rectangular cross section.

Motion Interplay as a Function of Patient Parameters and Spot Size in Spot Scanning Proton Therapy for Lung Cancer

PubMed Central

Grassberger, Clemens; Dowdell, Stephen; Lomax, Antony; Sharp, Greg; Shackleford, James; Choi, Noah; Willers, Henning; Paganetti, Harald

2013-01-01

Purpose Quantify the impact of respiratory motion on the treatment of lung tumors with spot scanning proton therapy. Methods and Materials 4D Monte Carlo simulations were used to assess the interplay effect, which results from relative motion of the tumor and the proton beam, on the dose distribution in the patient. Ten patients with varying tumor sizes (2.6-82.3cc) and motion amplitudes (3-30mm) were included in the study. We investigated the impact of the spot size, which varies between proton facilities, and studied single fractions and conventionally fractionated treatments. The following metrics were used in the analysis: minimum/maximum/mean dose, target dose homogeneity and 2-year local control rate (2y-LC). Results Respiratory motion reduces the target dose homogeneity, with the largest effects observed for the highest motion amplitudes. Smaller spot sizes (σ≈3mm) are inherently more sensitive to motion, decreasing target dose homogeneity on average by a factor ~2.8 compared to a larger spot size (σ≈13mm). Using a smaller spot size to treat a tumor with 30mm motion amplitude reduces the minimum dose to 44.7% of the prescribed dose, decreasing modeled 2y-LC from 87.0% to 2.7%, assuming a single fraction. Conventional fractionation partly mitigates this reduction, yielding a 2y-LC of 71.6%. For the large spot size, conventional fractionation increases target dose homogeneity and prevents a deterioration of 2y-LC for all patients. No correlation with tumor volume is observed. The effect on the normal lung dose distribution is minimal: observed changes in mean lung dose and lung V20 are <0.6Gy(RBE) and <1.7% respectively. Conclusions For the patients in this study, 2y-LC could be preserved in the presence of interplay using a large spot size and conventional fractionation. For treatments employing smaller spot sizes and/or in the delivery of single fractions, interplay effects can lead to significant deterioration of the dose distribution and lower 2y-LC. PMID:23462423

A study of the depth and size of concave cube Au nanoparticles as highly sensitive SERS probes

NASA Astrophysics Data System (ADS)

Romo-Herrera, J. M.; González, A. L.; Guerrini, L.; Castiello, F. R.; Alonso-Nuñez, G.; Contreras, O. E.; Alvarez-Puebla, R. A.

2016-03-01

High and uniform near fields are localized at the eight similar sharp corners of cubic gold nanoparticles. Moreover, by introducing concavity in the particle lateral planes, such field intensities can be further increased and tuned in the near infrared region without altering the overall size of the nanoparticles. Herein, we perform a thorough investigation of the morphological, crystallographic and plasmonic properties of concave gold nanocubes (GNCs) in the sub-70 nm size range, for their potential application as highly efficient SERS substrates in size-limiting cases. Theoretical calculations indicate that the highest increment of the near-field is located at the eight sharp tips and, interestingly, a medium near-field increment is also activated over the volume next to the concave surface. Remarkably, the plasmonic response of the concave cubic morphology showed great sensitivity to the concavity degree. Experimental SERS analysis nicely matches the outcome of the theoretical model, confirming that medium-sized concave GNCs (35 nm side length) possess the highest SERS activity upon excitation with a 633 nm laser, whereas larger 61 nm side concave GNCs dominate the optical response at 785 nm. Due to their size-intensity trade off, we envision that such small concave gold nanocubes can provide a highly active and efficient SERS platform for size-limiting applications, especially when near infrared excitations are required.High and uniform near fields are localized at the eight similar sharp corners of cubic gold nanoparticles. Moreover, by introducing concavity in the particle lateral planes, such field intensities can be further increased and tuned in the near infrared region without altering the overall size of the nanoparticles. Herein, we perform a thorough investigation of the morphological, crystallographic and plasmonic properties of concave gold nanocubes (GNCs) in the sub-70 nm size range, for their potential application as highly efficient SERS substrates in size-limiting cases. Theoretical calculations indicate that the highest increment of the near-field is located at the eight sharp tips and, interestingly, a medium near-field increment is also activated over the volume next to the concave surface. Remarkably, the plasmonic response of the concave cubic morphology showed great sensitivity to the concavity degree. Experimental SERS analysis nicely matches the outcome of the theoretical model, confirming that medium-sized concave GNCs (35 nm side length) possess the highest SERS activity upon excitation with a 633 nm laser, whereas larger 61 nm side concave GNCs dominate the optical response at 785 nm. Due to their size-intensity trade off, we envision that such small concave gold nanocubes can provide a highly active and efficient SERS platform for size-limiting applications, especially when near infrared excitations are required. Electronic supplementary information (ESI) available: Nanoparticle size distribution analysis (Fig. SI-1); extended TEM analysis on nanocubes morphology (Fig. SI-2, SI-3 and SI-4); comparison of GNCs size and concavity degree (Fig. SI-4); optical response calculations using the curved edges model (Fig. SI-5); simulated optical absorption spectra as a function of the concavity depth (Fig. SI-6); background SERS spectrum (Fig. SI-8) and details on the calculation of the SERS enhancement factors. See DOI: 10.1039/c6nr01155a

Migration Patterns, Densities, and Growth of Neritina punctulata Snails in Rio Espiritu Santo and Rio Mameyes, Northeastern Puerto Rico.

Treesearch

MARK PYRON; ALAN P. COVICH

2003-01-01

Snail size-frequency distributions in Rios Espiritu Santo and Mameyes, which drain the Luquillo Experimental Forest, Puerto Rico, showed that Neritina punctulata with shell lengths greater than 30 mm were the most abundant size class at upstream sites. The highest densities for all size classes were at the downstream sites. Growth rates were 0.015 mm/day for a large...

[Ichthyofauna associated to Thalassia testudinum at Lobos reef, Veracruz, Mexico: diversity and abundance].

PubMed

González-Gándara, Carlos; Trinidad-Martínez, Silvia del Carmen; Chávez-Morales, Víctor Manuel

2006-03-01

The diversity and abundance of ichthyofauna associated with Thalassia testudinum in the Lobos coral reef, Veracruz, Mexico, were studied in September and October 2002. Thirty six visual censuses in four sample sites were made using a 50 x 2 m transect belt. On each census, fish species, abundance and size were recorded. Leaf size and cover of T. testudinum were estimated. The similarity of fish groups was calculated with the Gower coefficient. The most abundant coral reef fishes were: Scarus iseri, Halichoeres bivittatus, Sparisoma radians, Stegastes adustus and Stegastes leucostictus. The highest density (0.04078 ind/m2) and biomass (0.72408 g/m2) of fish species were recorded in site II, where leaf size was greater (30.8 cm). The analysis of variance showed significant differences between sites in leaf size (F = 18.30856; p = 0.00001) and cover (H = 33.8119; p = 0.00001). These differences suggest a relationship between fish diversity and abundance, and T. testudinum leaf size and cover. The Gower similarity index produced two groups of fishes; one of them (site II) showed the highest abundance. In this reef, the fishes associated to sea grasses seem to reflect the characteristics of T. testudinum.

Immunization against leishmaniasis by PLGA nanospheres loaded with an experimental autoclaved Leishmania major (ALM) and Quillaja saponins.

PubMed

Tafaghodi, M; Eskandari, M; Kharazizadeh, M; Khamesipour, A; Jaafari, M R

2010-12-01

Immune responses against the Leishmania antigens are not sufficient to protect against a leishmania challenge. Therefore these antigens need to be potentiated by various adjuvants and delivery systems. In this study, Poly (d,l-lactide-co-glycolide (PLGA) nanospheres as antigen delivery system and Quillaja saponins (QS) as immunoadjuvant have been used to enhance the immune response against autoclaved Leishmania major (ALM). PLGA nanospheres were prepared by a double-emulsion (W/O/W) technique. Particulate characteristics were studied by scanning electron microscopy and particle size analysis. Mean diameter for nanospheres loaded with ALM+QS was 294 ± 106 nm. BALB/c mice were immunized three times in 3-weeks intervals using ALM plus QS loaded nanospheres [(ALM+QS)PLGA], ALM encapsulated with PLGA nanospheres [(ALM)PLGA], (ALM)PLGA + QS, ALM + QS, ALM alone or PBS. The intensity of infection induced by L. major challenge was assessed by measuring size of footpad swelling. The strongest protection, showed by significantly (P < 0.05) smaller footpad, were observed in mice immunized with (ALM)PLGA. The (ALM+QS)PLGA group showed the least protection and highest swelling, while the (ALM)PLGA+QS, ALM+QS and ALM showed an intermediate protection with no significant difference. The mice immunized with ALM and ALM+QS showed the highest IgG2a/IgG1 ratio (P < 0.01), followed by (ALM)PLGA+QS. The highest IFN-γ and lowest IL-4 production was seen in (ALM)PLGA+QS, ALM+QS groups. The highest parasite burden was observed in (ALM)PLGA+QS and (ALM+QS)PLGA groups. It is concluded that PLGA nanospheres as a vaccine delivery system could increase the protective immune responses, but QS adjuvant has a reverse effect on protective immune responses and the least protective responses were seen in the presence of this adjuvant.

Temperature affects long-term productivity and quality attributes of day-neutral strawberry for a space life-support system

NASA Astrophysics Data System (ADS)

Massa, Gioia D.; Chase, Elaine; Santini, Judith B.; Mitchell, Cary A.

2015-04-01

Strawberry (Fragaria x ananassa L.) is a promising candidate crop for space life-support systems with desirable sensory quality and health attributes. Day-neutral cultivars such as 'Seascape' are adaptable to a range of photoperiods, including short days that would save considerable energy for crop lighting without reductions in productivity or yield. Since photoperiod and temperature interact to affect strawberry growth and development, several diurnal temperature regimes were tested under a short photoperiod of 10 h per day for effects on yield and quality attributes of 'Seascape' strawberry during production cycles longer than 270 days. The coolest day/night temperature regime, 16°/8 °C, tended to produce smaller numbers of larger fruit than did the intermediate temperature range of 18°/10 °C or the warmest regime, 20°/12 °C, both of which produced similar larger numbers of smaller fruit. The intermediate temperature regime produced the highest total fresh mass of berries over an entire production cycle. Independent experiments examined either organoleptic or physicochemical quality attributes. Organoleptic evaluation indicated that fruit grown under the coolest temperature regime tended to score the highest for both hedonic preference and descriptive evaluation of sensory attributes related to sweetness, texture, aftertaste, and overall approval. The physicochemical quality attributes Brix, pH, and sugar/acid ratio were highest for fruits harvested from the coolest temperature regime and lower for those from the warmer temperature regimes. The cool-regime fruits also were lowest in titratable acidity. The yield parameters fruit number and size oscillated over the course of a production cycle, with a gradual decline in fruit size under all three temperature regimes. Brix and titratable acidity both decreased over time for all three temperature treatments, but sugar/acid ratio remained highest for the cool temperature regime over the entire production period. Periodic rejuvenation or replacement of strawberry propagules may be needed to maintain both quality and quantity of strawberry yield in space.

Sustainable thermoelectric materials fabricated by using Cu2Sn1-xZnxS3 nanoparticles as building blocks

NASA Astrophysics Data System (ADS)

Zhou, Wei; Shijimaya, Chiko; Takahashi, Mari; Miyata, Masanobu; Mott, Derrick; Koyano, Mikio; Ohta, Michihiro; Akatsuka, Takeo; Ono, Hironobu; Maenosono, Shinya

2017-12-01

Uniform Cu2Sn1-xZnxS3 (x = 0-0.2) nanoparticles (NPs) with a characteristic size of about 40 nm were chemically synthesized. The primary crystal phase of the NPs was wurtzite (WZ) with a mean crystalline size of about 20 nm. The NPs were sintered to form nanostructured pellets with different compositions preserving the composition and grain size of the original NPs by the pulse electric current sintering technique. The pellets had a zinc blende (ZB) structure with a residual WZ phase, and the mean crystalline size was found to remain virtually unchanged for all pellets. Among all samples, the pellets of Cu2Sn0.95Zn0.05S3 and Cu2Sn0.85Zn0.15S3 exhibited the highest ZT value (0.37 at 670 K) which is 10 times higher than that of a non-nanostructured Cu2SnS3 bulk crystal thanks to effective phonon scattering by nanograins, the phase-pure ZB crystal structure, and the increase in hole carrier density by Zn doping.

Evaluation of herbal cannabis characteristics by medical users: a randomized trial

PubMed Central

Ware, Mark A; Ducruet, Thierry; Robinson, Ann R

2006-01-01

Background Cannabis, in herbal form, is widely used as self-medication by patients with diseases such as HIV/AIDS and multiple sclerosis suffering from symptoms including pain, muscle spasticity, stress and insomnia. Valid clinical studies of herbal cannabis require a product which is acceptable to patients in order to maximize adherence to study protocols. Methods We conducted a randomized controlled crossover trial of 4 different herbal cannabis preparations among 8 experienced and authorized cannabis users with chronic pain. Preparations were varied with respect to grind size, THC content and humidity. Subjects received each preparation on a separate day and prepared the drug in their usual way in a dedicated and licensed clinical facility. They were asked to evaluate the products based on appearance (smell, colour, humidity, grind size, ease of preparation and overall appearance) and smoking characteristics (burn rate, hotness, harshness and taste). Five-point Likert scores were assigned to each characteristic. Scores were compared between preparations using ANOVA. Results Seven subjects completed the study, and the product with highest THC content (12%), highest humidity (14%) and largest grind size (10 mm) was rated highest overall. Significant differences were noted between preparations on overall appearance and colour (p = 0.003). Discussion While the small size of the study precludes broad conclusions, the study shows that medical cannabis users can appreciate differences in herbal product. A more acceptable cannabis product may increase recruitment and retention in clinical studies of medical cannabis. PMID:17101054

The luminescence and decay enhancement by variation in atomic size of alkaline earth metals in Pr3+ incorporated sodium lead borate glass

NASA Astrophysics Data System (ADS)

Lenkennavar, Susheela K.; Madhu, A.; Eraiah, B.; Kokila, M. K.

2018-05-01

The glasses used for the present study are prepared by the melting and quenching techniques of composition 20Na2O-10PbO-10MO-60B2O3-xPr2O3 (where, M=Ba, Ca, Sr and x= 0.5 mol% of Pr3+). For different alkaline considered with same Pr3+ concemtartion incorporation on present work as resulted in interesting facts. Due to the effect of different atomic size, the luminescence and life time of glasses are affected. Only for calcium alkaline earth metal incorporated samples has proved to have highest intensity in emission and longer life time. The detailed studies of them have been reported for the better understanding.

Production of laccase from Trametes versicolor by solid-state fermentation using olive leaves as a phenolic substrate.

PubMed

Aydinoğlu, Tuğba; Sargin, Sayit

2013-02-01

The aim of the present study was to investigate whether olive leaves were feasible as a substrate for laccase production by the white-rot fungus Trametes versicolor FPRL 28A INI under solid-state fermentation conditions. Different experiments were conducted to select the variables that allow obtaining high levels of laccase activity. In particular, the effects of the initial moisture content, substrate particle size, supplementation with inorganic and organic nitrogen sources were evaluated. Highest laccase activity (276.62 ± 25.67 U/g dry substrate) was achieved with 80 % initial moisture content and 1.4-1.6 mm particle size of the substrate supplemented with yeast extract (1 % (w/w) nitrogen). Such a high activity was obtained without any addition of inducers.

Effect of growth solution, membrane size and array connection on microbial fuel cell power supply for medical devices.

PubMed

Roxby, Daniel N; Nham Tran; Pak-Lam Yu; Nguyen, Hung T

2016-08-01

Implanted biomedical devices typically last a number of years before their batteries are depleted and a surgery is required to replace them. A Microbial Fuel Cell (MFC) is a device which by using bacteria, directly breaks down sugars to generate electricity. Conceptually there is potential to continually power implanted medical devices for the lifetime of a patient. To investigate the practical potential of this technology, H-Cell Dual Chamber MFCs were evaluated with two different growth solutions and measurements recorded for maximum power output both of individual MFCs and connected MFCs. Using Luria-Bertani media and connecting MFCs in a hybrid series and parallel arrangement with larger membrane sizes showed the highest power output and the greatest potential for replacing implanted batteries.

Effects of experimental warming on survival, phenology and morphology of an aquatic insect (Odonata)

PubMed Central

McCauley, Shannon J.; Hammond, John I.; Frances, Dachin N.; Mabry, Karen E.

2014-01-01

1. Organisms can respond to changing climatic conditions in multiple ways including changes in phenology, body size or morphology, and range shifts. Understanding how developmental temperatures affect insect life-history timing and morphology is crucial because body size and morphology affect multiple aspects of life history, including dispersal ability, while phenology can shape population performance and community interactions. 2. We experimentally assessed how developmental temperatures experienced by aquatic larvae affected survival, phenology, and adult morphology of dragonflies (Pachydiplax longipennis). Larvae were reared under 3 environmental temperatures: ambient, +2.5 °C, and +5 °C, corresponding to temperature projections for our study area 50 and 100 years in the future, respectively. Experimental temperature treatments tracked naturally-occurring variation. 3. We found clear effects of temperature in the rearing environment on survival and phenology: dragonflies reared at the highest temperatures had the lowest survival rates, and emerged from the larval stage approximately 3 weeks earlier than animals reared at ambient temperatures. There was no effect of rearing temperature on overall body size. Although neither the relative wing nor thorax size was affected by warming, a non-significant trend towards an interaction between sex and warming in relative thorax size suggests that males may be more sensitive to warming than females, a pattern that should be investigated further. 4. Warming strongly affected survival in the larval stage and the phenology of adult emergence. Understanding how warming in the developmental environment affects later life-history stages is critical to interpreting the consequences of warming for organismal performance. PMID:26028806

Systematic review finds major deficiencies in sample size methodology and reporting for stepped-wedge cluster randomised trials

PubMed Central

Martin, James; Taljaard, Monica; Girling, Alan; Hemming, Karla

2016-01-01

Background Stepped-wedge cluster randomised trials (SW-CRT) are increasingly being used in health policy and services research, but unless they are conducted and reported to the highest methodological standards, they are unlikely to be useful to decision-makers. Sample size calculations for these designs require allowance for clustering, time effects and repeated measures. Methods We carried out a methodological review of SW-CRTs up to October 2014. We assessed adherence to reporting each of the 9 sample size calculation items recommended in the 2012 extension of the CONSORT statement to cluster trials. Results We identified 32 completed trials and 28 independent protocols published between 1987 and 2014. Of these, 45 (75%) reported a sample size calculation, with a median of 5.0 (IQR 2.5–6.0) of the 9 CONSORT items reported. Of those that reported a sample size calculation, the majority, 33 (73%), allowed for clustering, but just 15 (33%) allowed for time effects. There was a small increase in the proportions reporting a sample size calculation (from 64% before to 84% after publication of the CONSORT extension, p=0.07). The type of design (cohort or cross-sectional) was not reported clearly in the majority of studies, but cohort designs seemed to be most prevalent. Sample size calculations in cohort designs were particularly poor with only 3 out of 24 (13%) of these studies allowing for repeated measures. Discussion The quality of reporting of sample size items in stepped-wedge trials is suboptimal. There is an urgent need for dissemination of the appropriate guidelines for reporting and methodological development to match the proliferation of the use of this design in practice. Time effects and repeated measures should be considered in all SW-CRT power calculations, and there should be clarity in reporting trials as cohort or cross-sectional designs. PMID:26846897

Analysis of seasonal variation in urban heat island effect for West Mediterranean Region of Turkey using Landsat 8 OLI/TIRS data

NASA Astrophysics Data System (ADS)

Aslan, Nagihan; KOC-SAN, Dilek

2016-07-01

Technological developments are accelerating day by day in 21st century which has brought social and economic developments. Besides, the word population is increasing rapidly and the majority of population lives in city center. Large and crowded cities, industrial areas and shopping centers are being built for providing human needs and wishes. For these purposes, natural resources are destroyed and urban climate is affected. The temperatures of urban areas can be warmer than the rural areas and differences in temperature between urban and surrounding rural areas were defined as Urban Heat Island (UHI). The objectives of this study are (i) to calculate Land Surface Temperatures (LST) for urban and vegetation areas in the selected cities, (ii) to determine the UHI effects and its change between seasons, (iii) to examine the relationship between city size and UHI effect magnitude. In this study, Landsat 8 OLI/TIRS imageries for winter (23 December 2013), summer (17 June 2014) and autumn (7 October 2014) seasons were used. The Antalya, Burdur and Isparta provinces that are placed in West Mediterranean Region of Turkey were selected as study areas. These three provinces have different characteristics. Antalya is the fifth biggest city of Turkey and its population growth is quite high. In addition, the summer population of this city increases severely, because of its tourism potential. On the other hand, Isparta and Burdur are relatively small cities when compared to Antalya with respect to population and urban area. In this study, firstly, the brightness temperatures and LST values are calculated from Landsat 8 thermal images. Secondly, urban areas are identified by an approach that combines emissivity image, Defense Meteorological Satellite Program - Operational Linescan System (DMSP/OLS) nighttime lights data and ASTER Global Digital Elevation Model (GDEM). In addition, the vegetation areas are defined by using emissivity image. Finally, the UHI effect is determined and compared with the temperatures in urban and vegetation areas for three cities. According to the obtained results, the highest LST values were observed in Antalya city for all seasons. When the seasonal changes were considered, it was found that the UHI effect is highest in summer season with 8.1°C temperatures in Antalya and it is followed by Isparta with 6.6°C and Burdur with 5.8°C. Additionally, it was observed that the UHI effect decreases in autumn and winter and it is negative for Burdur and Isparta cities in winter. When the city size and UHI effect relation was analyzed it can be stated that, the UHI effect magnitude is directly related to city size and it increases when the city size grows.

Fermentation pH Modulates the Size Distributions and Functional Properties of Gluconobacter albidus TMW 2.1191 Levan

PubMed Central

Ua-Arak, Tharalinee; Jakob, Frank; Vogel, Rudi F.

2017-01-01

Bacterial levan has gained an increasing interest over the last decades due to its unique characteristics and multiple possible applications. Levan and other exopolysaccharides (EPSs) production are usually optimized to obtain the highest concentration or yield while a possible change of the molecular size and mass during the production process is mostly neglected. In this study, the molar mass and radius of levan samples were monitored during fermentations with the food-grade, levan-producing acetic acid bacterium Gluconobacter (G.) albidus TMW 2.1191 in shake flasks (without pH control) and bioreactors (with pH control at 4.5, 5.5 and 6.5, respectively). In uncontrolled fermentations, the levan size/molar mass continuously decreased concomitantly with the continuous acidification of the nutrient medium. On the contrary, the amount, molar mass and size of levan could be directly influenced by controlling the pH during fermentation. Using equal initial substrate amounts, the largest weight average molar mass and geometric radius of levan were observed at constant pH 6.5, while the highest levan concentration was obtained at constant pH 4.5. Since there is a special demand to find suitable hydrocolloids from food-grade bacteria to develop novel gluten-free (GF) products, these differently produced levans were used for baking of GF breads, and the best quality improvement was obtained by addition of levan with the highest mass and radius. This work, therefore, demonstrates for the first time that one bacterial strain can produce specific high molecular weight fractions of one EPS type, which differ in properties and sizes among each other in dependence of the controllable production conditions. PMID:28522999

Comparison of Series of Vugs and Non-vuggy Synthetic Porous Media on Formation Damage

NASA Astrophysics Data System (ADS)

Khan, H.; DiCarlo, D. A.; Prodanovic, M.

2017-12-01

Produced water reinjection (PWRI) is an established cost-effective oil field practice where produced water is injected without any cleanup, for water flooding or disposal. Resultantly the cost of fresh injection fluid and/or processing produced water is saved. A common problem with injection of unprocessed water is formation damage in the near injection zone due to solids (fines) entrapment, causing a reduction in permeability and porosity of the reservoir. Most studies have used homogeneous porous media with unimodal grain sizes, while real world porous media often has a wide range of pores, up to and including vugs in carbonaceous rocks. Here we fabricate a series of vugs in synthetic porous media by sintering glass beads with large dissolvable inclusions. The process is found to be repeatable, allowing a similar vug configuration to be tested for different flow conditions. Bi-modal glass bead particles (25 & 100 micron) are injected at two different flow rates and three different injection concentrations. Porosity, permeability and effluent concentration are determined using CT scanning, pressure measurements and particle counting (Coulter counter), respectively. Image analysis is performed on the CT images to determine the change in vug size for each flow condition. We find that for the same flow conditions, heterogeneous media with series of vugs have an equal or greater permeability loss compared to homogeneous porous media. A significant change in permeability is observed at the highest concentration and flow rate as more particles approach the filter quickly, resulting in a greater loss in permeability in the lower end of the core. Image analysis shows the highest loss in vug size occurs at the low flow rate and highest concentration. The lower vug is completely blocked for this flow case. For all flow cases lower values of porosity are observed after the core floods. At low flow rate and medium concentration, a drastic loss in porosity is observed in the lower part of the core, after the vuggy zone. This trough is also distinctly clear in the homogeneous core for the same flow conditions. This study focuses on understanding the effect of pore heterogeneity on formation damage. We conclude that more damage is done deeper in vuggy formations at high flow rates, resulting in shorter injection cycle prior to clean up.

Effect of Anatase Synthesis on the Performance of Dye-Sensitized Solar Cells

NASA Astrophysics Data System (ADS)

Sánchez-García, Mario Alberto; Bokhimi, Xim; Maldonado-Álvarez, Arturo; Jiménez-González, Antonio Esteban

2015-07-01

Anatase nanoparticles were synthesized from a titanium isopropoxide solution using a hydrothermal process at different pressures in an autoclave system while keeping the volume of the solution constant. As the autoclave pressure was increased from 1 to 71 atm (23 to 210 °C), the crystal size in the nanoparticles increased from 9 to 13.8 nm. The anatase nanoparticles were used to build dye-sensitized solar cells (DSSC). Mesoporous films of this oxide were deposited over conducting SnO2:F substrates using the screen-printing technique and then annealed at 530 °C at 1 atm of air pressure. The morphology of the mesoporous film surface of anatase, studied using scanning electron microscopy, revealed that the crystal size and pore distribution were functions of the pressure conditions. The energy band gap of the films as a function of the crystal size exhibited quantum effects below 11.8 nm. The effects of the anatase synthesis conditions and properties of the mesoporous film on the DSSC-type solar cell parameters, η%, V OC, J SC, and FF, were also investigated: the mesoporous anatase films prepared at 200 °C (54 atm of pressure in the autoclave) and annealed at 530 °C in air generated the best solar cell, having the highest conversion efficiency.

Fisheries impacts on China's coastal ecosystems: Unmasking a pervasive 'fishing down' effect.

PubMed

Liang, Cui; Pauly, Daniel

2017-01-01

Intensive fishing can strongly impact marine ecosystems; among other things, it usually causes the mean trophic level of the catches to decline, an indicator of the occurrence of the 'fishing down' (FD) phenomenon. Although FD occurs throughout the world oceans, it can easily be masked by diverse factors, which has misled authors as to its generality. In this contribution, which uses the East China Sea as an example, we explore the masking effect on FD of the taxonomic coarseness of catch data, of assuming that individual sizes remain constant after intensive fishing, and the geographic expansion of fisheries. The result showed that all of these masking factors occur in the East China Sea, where only a few species are reported separately and the bulk of the catch is pooled into non-informative 'mixed fishes'. Also, the small mesh sizes and intensive fishing have reduced the sizes of fish and their trophic levels, while the fisheries have expanded offshore. Overall, taking the masking factors into account, the fishing down effect, i.e., the decline of the mean trophic level of the catch between 1979 and 2014 is in the order of 0.15 TL per decade, i.e., one of the highest estimates of FD in the world. Some ecological implications are presented.

Fisheries impacts on China's coastal ecosystems: Unmasking a pervasive ‘fishing down’ effect

PubMed Central

Pauly, Daniel

2017-01-01

Intensive fishing can strongly impact marine ecosystems; among other things, it usually causes the mean trophic level of the catches to decline, an indicator of the occurrence of the ‘fishing down’ (FD) phenomenon. Although FD occurs throughout the world oceans, it can easily be masked by diverse factors, which has misled authors as to its generality. In this contribution, which uses the East China Sea as an example, we explore the masking effect on FD of the taxonomic coarseness of catch data, of assuming that individual sizes remain constant after intensive fishing, and the geographic expansion of fisheries. The result showed that all of these masking factors occur in the East China Sea, where only a few species are reported separately and the bulk of the catch is pooled into non-informative ‘mixed fishes’. Also, the small mesh sizes and intensive fishing have reduced the sizes of fish and their trophic levels, while the fisheries have expanded offshore. Overall, taking the masking factors into account, the fishing down effect, i.e., the decline of the mean trophic level of the catch between 1979 and 2014 is in the order of 0.15 TL per decade, i.e., one of the highest estimates of FD in the world. Some ecological implications are presented. PMID:28267755

Tocotrienols in Vellozia gigantea leaves: occurrence and modulation by seasonal and plant size effects.

PubMed

Morales, Melanie; Garcia, Queila S; Siqueira-Silva, Advanio I; Silva, Mayara C; Munné-Bosch, Sergi

2014-08-01

Vitamin E occurs in all photosynthetic organisms examined to date. Tocopherols predominate in photosynthetic tissues (α-tocopherol being the major form), while either tocopherols or tocotrienols (or both) are present in seeds. Tocotrienols have not been described in photosynthetic tissues thus far. Here, we report on the presence of tocotrienols in leaves of higher plants. Both tocopherols and tocotrienols accumulated in leaves of Vellozia gigantea, an endemic plant found in the rupestrian fields of Serra do Cipó, Brazil. Increased plant size had a remarkable effect on the vitamin E composition of leaves, α-tocopherol and β-tocotrienol levels being highest in the largest individuals, but only during the dry season. Vitamin E levels positively correlated with lipid hydroxyperoxide levels, which also increased in the largest individuals during the dry season. However, the maximum efficiency of PSII photochemistry (F v/F m ratio) kept above 0.75 throughout the experiment, thus indicating absence of photoinhibitory damage to the photosynthetic apparatus. It is concluded that higher plants, such as V. gigantea, can accumulate tocotrienols in leaves, aside from tocopherols, and that the levels of both tocopherols and tocotrienols in the leaves of this species are strongly modulated by seasonal and plant size effects.

Iron Oxide Films Prepared by Rapid Thermal Processing for Solar Energy Conversion

PubMed Central

Wickman, B.; Bastos Fanta, A.; Burrows, A.; Hellman, A.; Wagner, J. B.; Iandolo, B.

2017-01-01

Hematite is a promising and extensively investigated material for various photoelectrochemical (PEC) processes for energy conversion and storage, in particular for oxidation reactions. Thermal treatments during synthesis of hematite are found to affect the performance of hematite electrodes considerably. Herein, we present hematite thin films fabricated via one-step oxidation of Fe by rapid thermal processing (RTP). In particular, we investigate the effect of oxidation temperature on the PEC properties of hematite. Films prepared at 750 °C show the highest activity towards water oxidation. These films show the largest average grain size and the highest charge carrier density, as determined from electron microscopy and impedance spectroscopy analysis. We believe that the fast processing enabled by RTP makes this technique a preferred method for investigation of novel materials and architectures, potentially also on nanostructured electrodes, where retaining high surface area is crucial to maximize performance. PMID:28091573

Utilization of alum sludge as chromium removal

NASA Astrophysics Data System (ADS)

Zahari, Nazirul Mubin; Sidek, Lariyah Mohd; Zulkifli, Muhammad Azmeer Asyraf; Hua, Chua Kok; Jalil, Nurulhidayah Abdul

2017-09-01

The amount of alum sludge produced at water treatment plant has become a problem where it is highly costly in order to dispose them. Various research was conducted to find the most suitable and economic alternative to recycle and reused of alum sludge. In this study, alum sludge was retrieved from Waterworks where it was dewatered, dried, grounded and sieved to obtain smallest particle sizes of alum sludge. The synthetic water was prepared at the laboratory in as it was used to imitate the properties of real water contaminated with chromium. This study was conducted to determine the percentage reduction of chromium concentration in synthetic water by using alum sludge as absorbent. The percentage reduction of chromium was observed under the effect of initial concentration of chromium and the height of alum sludge. The result indicates that chromium concentration reduction was the highest at the lowest initial concentration and at the highest height of alum sludge and vice versa.

Necrotizing enterocolitis and preterm infant gut bacteria

PubMed Central

Warner, Barbara B.; Tarr, Phillip I.

2016-01-01

Summary Necrotizing enterocolitis remains an intractable consequence of preterm birth. Gut microbial communities, especially bacterial communities, have long been suspected to play a role in the development of necrotizing enterocolitis. Direct-from-stool nucleic acid sequencing technology now offers insights into the make-up of these communities. Data are now converging on the roles of Gram-negative bacteria as causative agents, despite the dynamic nature of bacterial populations, the varying technologies and sampling strategies, and the overall small sample sizes in these case–control studies. Bacteria that confer protection from necrotizing enterocolitis have not been identified across studies. The beneficial effect of probiotics is not apparent in infants with birth weights <1000 g (these infants are at highest risk of, and have the highest case fatality rate from, necrotizing enterocolitis). Further work should be directed to the modulating gut microbes, or the products they produce, to prevent this devastating complication of preterm birth. PMID:27343151

Utilization of Cocoa Peel as Biosorbent for Oil and Color Removal in Palm Oil Mill Effluent (POME)

NASA Astrophysics Data System (ADS)

Pandia, S.; Hutagalung, A. T.; Siahaan, A. D.

2018-01-01

The aim of this study is to discover the effectiveness of cocoa peel as biosorbents for oil and color removal in POME. This study used biosorbent from cocoa peel with variation of particle size which passed through 70 mesh, 100 mesh, and 120 mesh and was activated with the ratio of biosorbent and 0,6 M HNO3 of 1:2, 1:4, and 1:6 (m/v). The adsorption process was carried out using biosorbent with the highest iodine number in varying biosorbent mass and contact time. The highest iodine number was 596,684 mg/g and obtained at particle size 120 mesh and the ratio of biosorbent : HNO3 as 1 : 4. The resulting biosorbents were analyzed for their characterization, such as vapor content, ash content, and volatile matter, including FT-IR and SEM-EDX. The POME were analyzed for their oil and color content, using gravimetric method and UV-Vis spectrophotometry. The best removal is were 80,88% for oil and 83.45% for color at 1.5 g biosorbent mass and 3 h contact time. The resullt for oil removal was close to the standard of Indonesian Environment Minister for oil in effluent. Also the adsorption of oil and color behaves as a pseudo-second-order kinetic models.

Bigger is better: honeybee colonies as distributed information-gathering systems.

PubMed

Donaldson-Matasci, Matina C; DeGrandi-Hoffman, Gloria; Dornhaus, Anna

2013-03-01

In collectively foraging groups, communication about food resources can play an important role in the organization of the group's activity. For example, the honeybee dance communication system allows colonies to selectively allocate foragers among different floral resources according to their quality. Because larger groups can potentially collect more information than smaller groups, they might benefit more from communication because it allows them to integrate and use that information to coordinate forager activity. Larger groups might also benefit more from communication because it allows them to dominate high-value resources by recruiting large numbers of foragers. By manipulating both colony size and the ability to communicate location information in the dance, we show that larger colonies of honeybees benefit more from communication than do smaller colonies. In fact, colony size and dance communication worked together to improve foraging performance; the estimated net gain per foraging trip was highest in larger colonies with unimpaired communication. These colonies also had the earliest peaks in foraging activity, but not the highest ones. This suggests they may find and recruit to resources more quickly, but not more heavily. The benefits of communication we observed in larger colonies are thus likely a result of more effective informationgathering due to massive parallel search rather than increased competitive ability due to heavy recruitment.

Recreational Diver Behavior and Contacts with Benthic Organisms in the Abrolhos National Marine Park, Brazil

NASA Astrophysics Data System (ADS)

Giglio, Vinicius J.; Luiz, Osmar J.; Schiavetti, Alexandre

2016-03-01

In the last two decades, coral reefs have become popular among recreational divers, especially inside marine protected areas. However, the impact caused by divers on benthic organisms may be contributing to the degradation of coral reefs. We analyzed the behavior of 142 scuba divers in the Abrolhos National Marine Park, Brazil. We tested the effect of diver profile, reef type, use of additional equipment, timing, and group size on diver behavior and their contacts with benthic organisms. Eighty-eight percent of divers contacted benthic organism at least once, with an average of eight touches and one damage per dive. No significant differences in contacts were verified among gender, group size, or experience level. Artificial reef received a higher rate of contact than pinnacle and fringe reefs. Specialist photographers and sidemount users had the highest rates, while non-users of additional equipment and mini camera users had the lowest contact rates. The majority of contacts were incidental and the highest rates occurred in the beginning of a dive. Our findings highlight the need of management actions, such as the provision of pre-dive briefing including ecological aspects of corals and beginning dives over sand bottoms or places with low coral abundance. Gathering data on diver behavior provides managers with information that can be used for tourism management.

Recreational Diver Behavior and Contacts with Benthic Organisms in the Abrolhos National Marine Park, Brazil.

PubMed

Giglio, Vinicius J; Luiz, Osmar J; Schiavetti, Alexandre

2016-03-01

In the last two decades, coral reefs have become popular among recreational divers, especially inside marine protected areas. However, the impact caused by divers on benthic organisms may be contributing to the degradation of coral reefs. We analyzed the behavior of 142 scuba divers in the Abrolhos National Marine Park, Brazil. We tested the effect of diver profile, reef type, use of additional equipment, timing, and group size on diver behavior and their contacts with benthic organisms. Eighty-eight percent of divers contacted benthic organism at least once, with an average of eight touches and one damage per dive. No significant differences in contacts were verified among gender, group size, or experience level. Artificial reef received a higher rate of contact than pinnacle and fringe reefs. Specialist photographers and sidemount users had the highest rates, while non-users of additional equipment and mini camera users had the lowest contact rates. The majority of contacts were incidental and the highest rates occurred in the beginning of a dive. Our findings highlight the need of management actions, such as the provision of pre-dive briefing including ecological aspects of corals and beginning dives over sand bottoms or places with low coral abundance. Gathering data on diver behavior provides managers with information that can be used for tourism management.

Protein and Bacterial Antifouling Behavior of Melt-Coextruded Nanofiber Mats.

PubMed

Kim, Si-Eun; Zhang, Cong; Advincula, Abigail A; Baer, Eric; Pokorski, Jonathan K

2016-04-13

Antifouling surfaces are important for biomedical devices to prevent secondary infections and mitigate the effects of the foreign body response. Herein, we describe melt-coextruded poly(ε-caprolactone) (PCL) nanofiber mats grafted with antifouling polymers. Nonwoven PCL fiber mats are produced using a multilayered melt coextrusion process followed by high-pressure hydroentanglement to yield porous patches. The resulting fiber mats show submicrometer cross-sectional fiber dimensions and yield pore sizes that were nearly uniform, with a mean pore size of 1.6 ± 0.9 μm. Several antifouling polymers, including hydrophilic, zwitterionic, and amphipathic molecules, are grafted to the surface of the mats using a two-step procedure that includes photochemistry followed by the copper-catalyzed azide-alkyne cycloaddition reaction. Fiber mats are evaluated using separate adsorption tests for serum proteins and E. coli. The results indicate that poly(oligo(ethylene glycol) methyl ether methacrylate)-co-(trifluoroethyl methacrylate) (poly(OEGMEMA-co-TFEMA)) grafted mats exhibit approximately 85% less protein adhesion and 97% less E. coli adsorption when compared to unmodified PCL fibermats. In dynamic antifouling testing, the amphiphilic fluorous polymer surface shows the highest flux and highest rejection value of foulants. The work presented within has implications on the high-throughput production of antifouling microporous patches for medical applications.

Bigger is better: honeybee colonies as distributed information-gathering systems

PubMed Central

Donaldson-Matasci, Matina C.; DeGrandi-Hoffman, Gloria; Dornhaus, Anna

2015-01-01

In collectively foraging groups, communication about food resources can play an important role in the organization of the group’s activity. For example, the honeybee dance communication system allows colonies to selectively allocate foragers among different floral resources according to their quality. Because larger groups can potentially collect more information than smaller groups, they might benefit more from communication because it allows them to integrate and use that information to coordinate forager activity. Larger groups might also benefit more from communication because it allows them to dominate high-value resources by recruiting large numbers of foragers. By manipulating both colony size and the ability to communicate location information in the dance, we show that larger colonies of honeybees benefit more from communication than do smaller colonies. In fact, colony size and dance communication worked together to improve foraging performance; the estimated net gain per foraging trip was highest in larger colonies with unimpaired communication. These colonies also had the earliest peaks in foraging activity, but not the highest ones. This suggests they may find and recruit to resources more quickly, but not more heavily. The benefits of communication we observed in larger colonies are thus likely a result of more effective informationgathering due to massive parallel search rather than increased competitive ability due to heavy recruitment. PMID:26213412

Reducing Class Size in New York City: Promise vs. Practice

ERIC Educational Resources Information Center

Farrie, Danielle; Johnson, Monete; Lecker, Wendy; Luhm, Theresa

2016-01-01

In the landmark school funding litigation, "Campaign for Fiscal Equity v. State" ("CFE"), the highest Court in New York recognized that reasonable class sizes are an essential element of a constitutional "sound basic education." In response to the rulings in the case, in 2007, the Legislature adopted a law mandating…

Center Size and Center Performance.

ERIC Educational Resources Information Center

Helburn, Suzanne; Morris, John

1996-01-01

Examined the impact of child care center size on cost, quality, and profits per child. Examined centers ranging from 40 to 80 children and found total cost and revenue per child were similar for small, medium, and large centers. Found profits per child were highest in large centers and that there was no relationship between center quality and…

Oil sorption by lignocellulosic fibers

Treesearch

Beom-Goo Lee; James S. Han; Roger M. Rowell

1999-01-01

The oil sorption capacities of cotton fiber, kenaf bast fiber, kenaf core fiber, and moss fiber were compared after refining, extraction, and reduction in particle sizes. The tests were conducted on diesel oil in a pure form. Cotton fiber showed the highest capacity, followed by kenaf core and bast fibers. Wetting, extraction, and reduction in particle size all...

Optimization of chip size and moisture content to obtain high, combined sugar recovery after sulfur dioxide-catalyzed steam pretreatment of softwood and enzymatic hydrolysis of the cellulosic component.

PubMed

Olsen, Colin; Arantes, Valdeir; Saddler, Jack

2015-01-01

The influence of chip size and moisture content on the combined sugar recovery after steam pretreatment of lodgepole pine and subsequent enzymatic hydrolysis of the cellulosic component were investigated using response surface methodology. Chip size had little influence on sugar recovery after both steam pretreatment and enzymatic hydrolysis. In contrast, the moisture of the chips greatly influenced the relative severity of steam pretreatment and, as a result, the combined sugar recovery from the hemicellulosic and cellulosic fractions. Irrespective of chip size and the pretreatment temperature, time, and SO2 loading that were used, the relative severity of pretreatment was highest at a moisture of 30-40w/w%. However, the predictive model indicated that an elevated moisture content of roughly 50w/w% (about the moisture content of a standard softwood mill chip) would result in the highest, combined sugar recovery (80%) over the widest range of steam pretreatment conditions. Copyright © 2015 Elsevier Ltd. All rights reserved.

The effects of low-intensity narrow-band blue-light treatment compared to bright white-light treatment in seasonal affective disorder.

PubMed

Meesters, Ybe; Duijzer, Wianne B; Hommes, Vanja

2018-05-01

Ever since a new photoreceptor was discovered with a highest sensitivity to 470-490 nm blue light, it has been speculated that blue light has some advantages in the treatment of Seasonal Affective Disorder (SAD) over more traditional treatments. In this study we compared the effects of exposure to narrow-band blue light (BLUE) to those of broad-wavelength white light (BLT) in the treatment of SAD. In a 15-day design, 45 patients suffering from SAD completed 30-min sessions of light treatment on 5 consecutive days. 21 subjects received white-light treatment (BLT, broad-wavelength without UV, 10 000 lx, irradiance 31.7 W/m 2 ), 24 subjects received narrow-band blue light (BLUE, 100 lx, irradiance 1.0 W/m 2 ). All participants completed weekly questionnaires concerning mood and energy levels, and were also assessed by means of the SIGH-SAD, which is the primary outcome measure. On day 15, SIGH-SAD ratings were significantly lower than on day 1 (BLT 73.2%, effect size 3.37; BLUE 67%, effect size 2.63), which outcomes were not statistically significant different between both conditions. Small sample size. Light treatment is an effective treatment for SAD. The use of narrow-band blue light is equally effective as a treatment using bright white-light. Copyright © 2018 Elsevier B.V. All rights reserved.

Metabolism during flight in two species of bats, Phyllostomus hastatus and Pteropus gouldii.

PubMed

Thomas, S P

1975-08-01

The energetic cost of flight in a wind-tunnel was measured at various combinations of speed and flight angle from two species of bats whose body masses differ by almost an order of magnitude. The highest mean metabolic rate per unit body mass measured from P. hastatus (mean body mass, 0.093 kg) was 130.4 Wkg-1, and that for P. gouldii (mean body mass, 0.78 kg) was 69.6 Wkg-1. These highest metabolic rates, recorded from flying bats, are essentially the same as those predicted for flying birds of the same body masses, but are from 2.5 to 3.0 times greater than the highest metabolic rates of which similar-size exercising terrestrial mammals appear capable. The lowest mean rate of energy utilization per unit body mass P. hastatus required to sustain level flight was 94.2 Wkg-1 and that for P. gouldii was 53.4 Wkg-1. These data from flying bats together with comparable data for flying birds all fall along a straight line when plotted on double logarithmic coordinates as a function of body mass. Such data show that even the lowest metabolic requirements of bats and birds during level flight are about twice the highest metabolic capabilities of similar-size terrestrial mammals. Flying bats share with flying birds the ability to move substantially greater distance per unit energy consumed than walking or running mammals. Calculations show that P. hastatus requires only one-sixth the energy to cover a given distance as does the same-size terrestrial mammal, while P. gouldii requires one-fourth the energy of the same-size terrestrial mammal. An empirically derived equation is presented which enables one to make estimates of the metabolic rates of bats and birds during level flight in nature from body mass data alone. Metabolic data obtained in this study are compared with predictions calculated from an avian flight theory.

Nano-sized Ni-doped carbon aerogel for supercapacitor.

PubMed

Lee, Yoon Jae; Jung, Ji Chul; Park, Sunyoung; Seo, Jeong Gil; Baeck, Sung-Hyeon; Yoon, Jung Rag; Yi, Jongheop; Song, In Kyu

2011-07-01

Carbon aerogel was prepared by polycondensation of resorcinol with formaldehyde using sodium carbonate as a catalyst in ambient conditions. Nano-sized Ni-doped carbon aerogel was then prepared by a precipitation method in an ethanol solvent. In order to elucidate the effect of nickel content on electrochemical properties, Ni-doped carbon aerogels (21, 35, 60, and 82 wt%) were prepared and their performance for supercapacitor electrode was investigated. Electrochemical properties of Ni-doped carbon aerogel electrodes were measured by cyclic voltammetry at a scan rate of 10 mV/sec and charge/discharge test at constant current of 1 A/g in 6 M KOH electrolyte. Among the samples prepared, 35 wt% Ni-doped carbon aerogel (Ni/CA-35) showed the highest capacitance (110 F/g) and excellent charge/discharge behavior. The enhanced capacitance of Ni-doped carbon aerogel was attributed to the faradaic redox reactions of nano-sized nickel oxide. Moreover, Ni-doped carbon aerogel exhibited quite stable cyclability, indicating long-term electrochemical stability.

Synthesis and atomic scale characterization of Er2O3 nanoparticles: enhancement of magnetic properties and changes in the local structure

NASA Astrophysics Data System (ADS)

Corrêa, Eduardo L.; Bosch-Santos, Brianna; Freitas, Rafael S.; Potiens, Maria da Penha A.; Saiki, Mitiko; Carbonari, Artur W.

2018-05-01

In the investigation reported in this paper a modified thermal decomposition method was developed to produce very small Er2O3 nanoparticles (NPs). Particles structure, shape and size were characterized by x-ray diffraction and transmission electron microscopy which showed that the synthesis by thermal decomposition under O2 atmosphere produced very small and monodisperse NPs, allowing the investigation of finite-size and surface effects. Results of magnetization measurements showed that the smallest particles present the highest values of susceptibility that decrease as particle size increases. Specific heat measurements indicate that the sample with the smallest NPs (diameter ∼5 nm) has a Néel temperature of 0.54 K. The local structure of particles was investigated by measurements of hyperfine interactions with perturbed angular correlation spectroscopy using 111Cd as probe nuclei replacing the cationic sites. Results showed that the relative population of sites 8b increases in both the core and surface layer of particles.

Highly adhesive and high fatigue-resistant copper/PET flexible electronic substrates

NASA Astrophysics Data System (ADS)

Park, Sang Jin; Ko, Tae-Jun; Yoon, Juil; Moon, Myoung-Woon; Oh, Kyu Hwan; Han, Jun Hyun

2018-01-01

A voidless Cu/PET substrate is fabricated by producing a superhydrophilic PET surface comprised of nanostructures with large width and height and then by Cu electroless plating. Effect of PET surface nanostructure size on the failure mechanism of the Cu/PET substrate is studied. The fabricated Cu/PET substrate exhibits a maximum peel strength of 1300 N m-1 without using an interlayer, and virtually no increase in electrical resistivity under the extreme cyclic bending condition of 1 mm curvature radius after 300 k cycles. The authors find that there is an optimum nanostructure size for the highest Cu/PET adhesion strength, and the failure mechanism of the Cu/PET flexible substrate depends on the PET surface nanostructure size. Thus, this work presents the possibility to produce flexible metal/polymer electronic substrates that have excellent interfacial adhesion between the metal and polymer and high fatigue resistance against repeated bending. Such metal/polymer substrates provides new design opportunities for wearable electronic devices that can withstand harsh environments and have extended lifetimes.

Slow swimming, fast strikes: effects of feeding behavior on scaling of anaerobic metabolism in epipelagic squid.

PubMed

Trueblood, Lloyd A; Seibel, Brad A

2014-08-01

Many pelagic fishes engage prey at high speeds supported by high metabolic rates and anaerobic metabolic capacity. Epipelagic squids are reported to have among the highest metabolic rates in the oceans as a result of demanding foraging strategies and the use of jet propulsion, which is inherently inefficient. This study examined enzymatic proxies of anaerobic metabolism in two species of pelagic squid, Dosidicus gigas and Doryteuthis pealeii (Lesueur 1821), over a size range of six orders of magnitude. We hypothesized that activity of the anaerobically poised enzymes would be high and increase with size as in ecologically similar fishes. In contrast, we demonstrate that anaerobic metabolic capacity in these organisms scales negatively with body mass. We explored several cephalopod-specific traits, such as the use of tentacles to capture prey, body morphology and reduced relative prey size of adult squids, that may create a diminished reliance on anaerobically fueled burst activity during prey capture in large animals. © 2014. Published by The Company of Biologists Ltd.

Synthesis and atomic scale characterization of Er2O3 nanoparticles: enhancement of magnetic properties and changes in the local structure.

PubMed

Corrêa, Eduardo L; Bosch-Santos, Brianna; Freitas, Rafael S; da Penha A Potiens, Maria; Saiki, Mitiko; Carbonari, Artur W

2018-05-18

In the investigation reported in this paper a modified thermal decomposition method was developed to produce very small Er 2 O 3 nanoparticles (NPs). Particles structure, shape and size were characterized by x-ray diffraction and transmission electron microscopy which showed that the synthesis by thermal decomposition under O 2 atmosphere produced very small and monodisperse NPs, allowing the investigation of finite-size and surface effects. Results of magnetization measurements showed that the smallest particles present the highest values of susceptibility that decrease as particle size increases. Specific heat measurements indicate that the sample with the smallest NPs (diameter ∼5 nm) has a Néel temperature of 0.54 K. The local structure of particles was investigated by measurements of hyperfine interactions with perturbed angular correlation spectroscopy using 111 Cd as probe nuclei replacing the cationic sites. Results showed that the relative population of sites 8b increases in both the core and surface layer of particles.

Systematic Evaluation of Molecular Networks for Discovery of Disease Genes.

PubMed

Huang, Justin K; Carlin, Daniel E; Yu, Michael Ku; Zhang, Wei; Kreisberg, Jason F; Tamayo, Pablo; Ideker, Trey

2018-04-25

Gene networks are rapidly growing in size and number, raising the question of which networks are most appropriate for particular applications. Here, we evaluate 21 human genome-wide interaction networks for their ability to recover 446 disease gene sets identified through literature curation, gene expression profiling, or genome-wide association studies. While all networks have some ability to recover disease genes, we observe a wide range of performance with STRING, ConsensusPathDB, and GIANT networks having the best performance overall. A general tendency is that performance scales with network size, suggesting that new interaction discovery currently outweighs the detrimental effects of false positives. Correcting for size, we find that the DIP network provides the highest efficiency (value per interaction). Based on these results, we create a parsimonious composite network with both high efficiency and performance. This work provides a benchmark for selection of molecular networks in human disease research. Copyright © 2018 Elsevier Inc. All rights reserved.

Ranking of predictor variables based on effect size criterion provides an accurate means of automatically classifying opinion column articles

NASA Astrophysics Data System (ADS)

Legara, Erika Fille; Monterola, Christopher; Abundo, Cheryl

2011-01-01

We demonstrate an accurate procedure based on linear discriminant analysis that allows automatic authorship classification of opinion column articles. First, we extract the following stylometric features of 157 column articles from four authors: statistics on high frequency words, number of words per sentence, and number of sentences per paragraph. Then, by systematically ranking these features based on an effect size criterion, we show that we can achieve an average classification accuracy of 93% for the test set. In comparison, frequency size based ranking has an average accuracy of 80%. The highest possible average classification accuracy of our data merely relying on chance is ∼31%. By carrying out sensitivity analysis, we show that the effect size criterion is superior than frequency ranking because there exist low frequency words that significantly contribute to successful author discrimination. Consistent results are seen when the procedure is applied in classifying the undisputed Federalist papers of Alexander Hamilton and James Madison. To the best of our knowledge, the work is the first attempt in classifying opinion column articles, that by virtue of being shorter in length (as compared to novels or short stories), are more prone to over-fitting issues. The near perfect classification for the longer papers supports this claim. Our results provide an important insight on authorship attribution that has been overlooked in previous studies: that ranking discriminant variables based on word frequency counts is not necessarily an optimal procedure.

Effect of high-pressure homogenization on droplet size distribution and rheological properties of ice cream mixes.

PubMed

Innocente, N; Biasutti, M; Venir, E; Spaziani, M; Marchesini, G

2009-05-01

The effect of different homogenization pressures (15/3 MPa and 97/3 MPa) on fat globule size and distribution as well as on structure-property relationships of ice cream mixes was investigated. Dynamic light scattering, steady shear, and dynamic rheological analyses were performed on mixes with different fat contents (5 and 8%) and different aging times (4 and 20 h). The homogenization of ice cream mixes determined a change from bimodal to monomodal particle size distributions and a reduction in the mean particle diameter. Mean fat globule diameters were reduced at higher pressure, but the homogenization effect on size reduction was less marked with the highest fat content. The rheological behavior of mixes was influenced by both the dispersed and the continuous phases. Higher fat contents caused greater viscosity and dynamic moduli. The lower homogenization pressure (15/3 MPa) mainly affected the dispersed phase and resulted in a more pronounced viscosity reduction in the higher fat content mixes. High-pressure homogenization (97/3 MPa) greatly enhanced the viscoelastic properties and the apparent viscosity. Rheological results indicated that unhomogenized and 15/3 MPa homogenized mixes behaved as weak gels. The 97/3 MPa treatment led to stronger gels, perhaps as the overall result of a network rearrangement or interpenetrating network formation, and the fat globules were found to behave as interactive fillers. High-pressure homogenization determined the apparent viscosity of 5% fat to be comparable to that of 8% fat unhomogenized mix.

Climatic and Landscape Influences on Fire Regimes from 1984 to 2010 in the Western United States

PubMed Central

Liu, Zhihua; Wimberly, Michael C.

2015-01-01

An improved understanding of the relative influences of climatic and landscape controls on multiple fire regime components is needed to enhance our understanding of modern fire regimes and how they will respond to future environmental change. To address this need, we analyzed the spatio-temporal patterns of fire occurrence, size, and severity of large fires (> 405 ha) in the western United States from 1984–2010. We assessed the associations of these fire regime components with environmental variables, including short-term climate anomalies, vegetation type, topography, and human influences, using boosted regression tree analysis. Results showed that large fire occurrence, size, and severity each exhibited distinctive spatial and spatio-temporal patterns, which were controlled by different sets of climate and landscape factors. Antecedent climate anomalies had the strongest influences on fire occurrence, resulting in the highest spatial synchrony. In contrast, climatic variability had weaker influences on fire size and severity and vegetation types were the most important environmental determinants of these fire regime components. Topography had moderately strong effects on both fire occurrence and severity, and human influence variables were most strongly associated with fire size. These results suggest a potential for the emergence of novel fire regimes due to the responses of fire regime components to multiple drivers at different spatial and temporal scales. Next-generation approaches for projecting future fire regimes should incorporate indirect climate effects on vegetation type changes as well as other landscape effects on multiple components of fire regimes. PMID:26465959

Grinding energy and physical properties of chopped and hammer-milled barley, wheat, oat, and canola straws

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

J.S. Tumuluru; L.G. Tabil; Y. Song

2014-01-01

In the present study, specific energy for grinding and physical properties of wheat, canola, oat and barley straw grinds were investigated. The initial moisture content of the straw was about 0.13–0.15 (fraction total mass basis). Particle size reduction experiments were conducted in two stages: (1) a chopper without a screen, and (2) a hammer mill using three screen sizes (19.05, 25.4, and 31.75 mm). The lowest grinding energy (1.96 and 2.91 kWh t-1) was recorded for canola straw using a chopper and hammer mill with 19.05-mm screen size, whereas the highest (3.15 and 8.05 kWh t-1) was recorded for barleymore » and oat straws. The physical properties (geometric mean particle diameter, bulk, tapped and particle density, and porosity) of the chopped and hammer-milled wheat, barley, canola, and oat straw grinds measured were in the range of 0.98–4.22 mm, 36–80 kg m-3, 49–119 kg m-3, 600–1220 kg m-3, and 0.9–0.96, respectively. The average mean particle diameter was highest for the chopped wheat straw (4.22-mm) and lowest for the canola grind (0.98-mm). The canola grinds produced using the hammer mill (19.05-mm screen size) had the highest bulk and tapped density of about 80 and 119 kg m-3; whereas, the wheat and oat grinds had the lowest of about 58 and 88–90 kg m-3. The results indicate that the bulk and tapped densities are inversely proportional to the particle size of the grinds. The flow properties of the grinds calculated are better for chopped straws compared to hammer milled using smaller screen size (19.05 mm).« less

Estimating the Effects of Parental Divorce and Death With Fixed Effects Models.

PubMed

Amato, Paul R; Anthony, Christopher J

2014-04-01

The authors used child fixed effects models to estimate the effects of parental divorce and death on a variety of outcomes using 2 large national data sets: (a) the Early Childhood Longitudinal Study, Kindergarten Cohort (kindergarten through the 5th grade) and (b) the National Educational Longitudinal Study (8th grade to the senior year of high school). In both data sets, divorce and death were associated with multiple negative outcomes among children. Although evidence for a causal effect of divorce on children was reasonably strong, effect sizes were small in magnitude. A second analysis revealed a substantial degree of variability in children's outcomes following parental divorce, with some children declining, others improving, and most not changing at all. The estimated effects of divorce appeared to be strongest among children with the highest propensity to experience parental divorce.

Power, effects, confidence, and significance: an investigation of statistical practices in nursing research.

PubMed

Gaskin, Cadeyrn J; Happell, Brenda

2014-05-01

To (a) assess the statistical power of nursing research to detect small, medium, and large effect sizes; (b) estimate the experiment-wise Type I error rate in these studies; and (c) assess the extent to which (i) a priori power analyses, (ii) effect sizes (and interpretations thereof), and (iii) confidence intervals were reported. Statistical review. Papers published in the 2011 volumes of the 10 highest ranked nursing journals, based on their 5-year impact factors. Papers were assessed for statistical power, control of experiment-wise Type I error, reporting of a priori power analyses, reporting and interpretation of effect sizes, and reporting of confidence intervals. The analyses were based on 333 papers, from which 10,337 inferential statistics were identified. The median power to detect small, medium, and large effect sizes was .40 (interquartile range [IQR]=.24-.71), .98 (IQR=.85-1.00), and 1.00 (IQR=1.00-1.00), respectively. The median experiment-wise Type I error rate was .54 (IQR=.26-.80). A priori power analyses were reported in 28% of papers. Effect sizes were routinely reported for Spearman's rank correlations (100% of papers in which this test was used), Poisson regressions (100%), odds ratios (100%), Kendall's tau correlations (100%), Pearson's correlations (99%), logistic regressions (98%), structural equation modelling/confirmatory factor analyses/path analyses (97%), and linear regressions (83%), but were reported less often for two-proportion z tests (50%), analyses of variance/analyses of covariance/multivariate analyses of variance (18%), t tests (8%), Wilcoxon's tests (8%), Chi-squared tests (8%), and Fisher's exact tests (7%), and not reported for sign tests, Friedman's tests, McNemar's tests, multi-level models, and Kruskal-Wallis tests. Effect sizes were infrequently interpreted. Confidence intervals were reported in 28% of papers. The use, reporting, and interpretation of inferential statistics in nursing research need substantial improvement. Most importantly, researchers should abandon the misleading practice of interpreting the results from inferential tests based solely on whether they are statistically significant (or not) and, instead, focus on reporting and interpreting effect sizes, confidence intervals, and significance levels. Nursing researchers also need to conduct and report a priori power analyses, and to address the issue of Type I experiment-wise error inflation in their studies. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

Zinc oxide and silver nanoparticles toxicity in the baker's yeast, Saccharomyces cerevisiae.

PubMed

Galván Márquez, Imelda; Ghiyasvand, Mergan; Massarsky, Andrey; Babu, Mohan; Samanfar, Bahram; Omidi, Katayoun; Moon, Thomas W; Smith, Myron L; Golshani, Ashkan

2018-01-01

Engineered nanomaterials (ENMs) are increasingly incorporated into a variety of commercial applications and consumer products; however, ENMs may possess cytotoxic properties due to their small size. This study assessed the effects of two commonly used ENMs, zinc oxide nanoparticles (ZnONPs) and silver nanoparticles (AgNPs), in the model eukaryote Saccharomyces cerevisiae. A collection of ≈4600 S. cerevisiae deletion mutant strains was used to deduce the genes, whose absence makes S. cerevisiae more prone to the cytotoxic effects of ZnONPs or AgNPs. We demonstrate that S. cerevisiae strains that lack genes involved in transmembrane and membrane transport, cellular ion homeostasis, and cell wall organization or biogenesis exhibited the highest sensitivity to ZnONPs. In contrast, strains that lack genes involved in transcription and RNA processing, cellular respiration, and endocytosis and vesicular transport exhibited the highest sensitivity to AgNPs. Secondary assays confirmed that ZnONPs affected cell wall function and integrity, whereas AgNPs exposure decreased transcription, reduced endocytosis, and led to a dysfunctional electron transport system. This study supports the use of S. cerevisiae Gene Deletion Array as an effective high-throughput technique to determine cellular targets of ENM toxicity.

Resveratrol reduces the levels of circulating androgen precursors but has no effect on, testosterone, dihydrotestosterone, PSA levels or prostate volume. A 4-month randomised trial in middle-aged men.

PubMed

Kjaer, Thomas Nordstrøm; Ornstrup, Marie Juul; Poulsen, Morten Møller; Jørgensen, Jens Otto Lunde; Hougaard, David Michael; Cohen, Arieh Sierra; Neghabat, Shadman; Richelsen, Bjørn; Pedersen, Steen Bønløkke

2015-09-01

Resveratrol is a naturally occurring polyphenol with purported inhibitory effects on prostate growth and cancer development. A number of studies have demonstrated that resveratrol reduces prostate growth in animal models and reduces prostate cell growth in vitro. Based on these pre-clinical findings, interest in resveratrol is increasing in relation to the management of benign prostate hyperplasia (BPH) and prostate cancer. So far, no human trials have evaluated the effects of resveratrol on circulating androgens, prostate size, or biochemical markers of prostate size. In a randomized placebo controlled clinical study using two doses of resveratrol (150 mg or 1,000 mg resveratrol daily) for 4 months, we evaluated the effects on prostate size, prostate specific antigen (PSA) and sex steroid hormones in 66 middle-aged men suffering from the metabolic syndrome(MetS). At baseline, prostate size and PSA were positively correlated (R = 0.34, P < 0.007) as was prostate size and age (R = 0.37, P < 0.003). Prostate size did not correlate with testosterone, free testosterone, dihydrotestosterone (DHT), or any other androgen precursor at baseline. The highest dose of resveratrol lowered the serum level of androstenedione 24% (P = 0.052), dehydroepiandrosterone (DHEA) 41% (P < 0.01), and dehydroepiandrosterone-sulphate (DHEAS) 50% (p<0.001), compared to the control group. However, prostate size and levels of PSA, testosterone, free testosterone and DHT remained unchanged. In this population of middle-aged men suffering from MetS, high dose resveratrol (1,000 mg daily) administration for 4 months significantly lowered serum levels of the androgen precursors androstenedione, DHEA and DHEAS, whereas prostate size and circulating levels of PSA, testosterone, free testosterone, and dihydrotestosterone were unaffected. The present study suggests that resveratrol does not affect prostate volume in healthy middle-aged men as measured by PSA levels and CT acquired prostate volumes. Consequently, we find no support for the use of resveratrol in the treatment of benign prostate hyperplasia. © 2015 Wiley Periodicals, Inc.

Effect of different drying techniques on flowability characteristics and chemical properties of natural carbohydrate-protein Gum from durian fruit seed

PubMed Central

2013-01-01

Background A natural carbohydrate biopolymer was extracted from the agricultural biomass waste (durian seed). Subsequently, the crude biopolymer was purified by using the saturated barium hydroxide to minimize the impurities. Finally, the effect of different drying techniques on the flow characteristics and functional properties of the purified biopolymer was investigated. The present study elucidated the main functional characteristics such as flow characteristics, water- and oil-holding capacity, solubility, and foaming capacity. Results In most cases except for oven drying, the bulk density decreased, thus increasing the porosity. This might be attributed to the increase in the inter-particle voids of smaller sized particles with larger contact surface areas per unit volume. The current study revealed that oven-dried gum and freeze-dried gum had the highest and lowest compressibility index, thus indicating the weakest and strongest flowability among all samples. In the present work, the freeze-dried gum showed the lowest angle of repose, bulk, tapped and true density. This indicates the highest porosity degree of freeze dried gum among dried seed gums. It also exhibited the highest solubility, and foaming capacity thus providing the most desirable functional properties and flow characteristics among all drying techniques. Conclusion The present study revealed that freeze drying among all drying techniques provided the most desirable functional properties and flow characteristics for durian seed gum. PMID:23289739

Adaptation of the Long-Lived Monocarpic Perennial Saxifraga longifolia to High Altitude1[OPEN

PubMed Central

Morales, Melanie; Fleta-Soriano, Eva; Garcia, Maria B.

2016-01-01

Global change is exerting a major effect on plant communities, altering their potential capacity for adaptation. Here, we aimed at unveiling mechanisms of adaptation to high altitude in an endemic long-lived monocarpic, Saxifraga longifolia, by combining demographic and physiological approaches. Plants from three altitudes (570, 1100, and 2100 m above sea level [a.s.l.]) were investigated in terms of leaf water and pigment contents, and activation of stress defense mechanisms. The influence of plant size on physiological performance and mortality was also investigated. Levels of photoprotective molecules (α-tocopherol, carotenoids, and anthocyanins) increased in response to high altitude (1100 relative to 570 m a.s.l.), which was paralleled by reduced soil and leaf water contents and increased ABA levels. The more demanding effect of high altitude on photoprotection was, however, partly abolished at very high altitudes (2100 m a.s.l.) due to improved soil water contents, with the exception of α-tocopherol accumulation. α-Tocopherol levels increased progressively at increasing altitudes, which paralleled with reductions in lipid peroxidation, thus suggesting plants from the highest altitude effectively withstood high light stress. Furthermore, mortality of juveniles was highest at the intermediate population, suggesting that drought stress was the main environmental driver of mortality of juveniles in this rocky plant species. Population structure and vital rates in the high population evidenced lower recruitment and mortality in juveniles, activation of clonal growth, and absence of plant size-dependent mortality. We conclude that, despite S. longifolia has evolved complex mechanisms of adaptation to altitude at the cellular, whole-plant and population levels, drought events may drive increased mortality in the framework of global change. PMID:27440756

Adaptation of the Long-Lived Monocarpic Perennial Saxifraga longifolia to High Altitude.

PubMed

Munné-Bosch, Sergi; Cotado, Alba; Morales, Melanie; Fleta-Soriano, Eva; Villellas, Jesús; Garcia, Maria B

2016-10-01

Global change is exerting a major effect on plant communities, altering their potential capacity for adaptation. Here, we aimed at unveiling mechanisms of adaptation to high altitude in an endemic long-lived monocarpic, Saxifraga longifolia, by combining demographic and physiological approaches. Plants from three altitudes (570, 1100, and 2100 m above sea level [a.s.l.]) were investigated in terms of leaf water and pigment contents, and activation of stress defense mechanisms. The influence of plant size on physiological performance and mortality was also investigated. Levels of photoprotective molecules (α-tocopherol, carotenoids, and anthocyanins) increased in response to high altitude (1100 relative to 570 m a.s.l.), which was paralleled by reduced soil and leaf water contents and increased ABA levels. The more demanding effect of high altitude on photoprotection was, however, partly abolished at very high altitudes (2100 m a.s.l.) due to improved soil water contents, with the exception of α-tocopherol accumulation. α-Tocopherol levels increased progressively at increasing altitudes, which paralleled with reductions in lipid peroxidation, thus suggesting plants from the highest altitude effectively withstood high light stress. Furthermore, mortality of juveniles was highest at the intermediate population, suggesting that drought stress was the main environmental driver of mortality of juveniles in this rocky plant species. Population structure and vital rates in the high population evidenced lower recruitment and mortality in juveniles, activation of clonal growth, and absence of plant size-dependent mortality. We conclude that, despite S. longifolia has evolved complex mechanisms of adaptation to altitude at the cellular, whole-plant and population levels, drought events may drive increased mortality in the framework of global change. © 2016 American Society of Plant Biologists. All Rights Reserved.

Ambient temperature effects on growth of milkfish (Chanos chanos) at aquaculture scale in Blanakan, West Java

NASA Astrophysics Data System (ADS)

A'yun, Q.; Takarina, N. D.

2017-07-01

Growth and survival of fishes can be influenced by temperature [1]. Variation among size like weight and length could be the preference how temperature works on growth of fishes [2]. This could be key factor in determining in production as well as market demand since people like heavy and large fishes. The main purpose of this study was to determine the effects of temperature on the growth of milkfish (Chanos Chanos) on weight and length parameters in fish farms Blanakan. This study conducted to assess the optimal temperature for the growth of fish of different sizes to optimize the culture conditions for raising milkfishes in scale cultivation in Blanakan, West Java. Milkfishes were reared in the aquaculture Blanakan ponds because they can adapt very well. The weight and length of milkfishes were measured together with water temperature. The results showed the temperature min (tmin) and max (tmax) were ranged from 29-35 °C. Based on the result, there were significant differences in mean weight (p = 0.00) between temperature with the fish reared in tmax group having the lowest mean weight (99.87±11.51 g) and fish reared in tmin group having the highest mean weight (277.17±33.76 g). Likewise, the significant differences were also observed in mean length (p = 0.00) between temperature with the fish reared in tmax group having the lowest mean length (176.50±12.50 mm) and fish reared in tmin group having the highest mean length (183.60±23.86 mm). Therefore, this paper confirmed the significant effects of temperature on the fish growth reared in aquaculture ponds. More, maintaining aquaculture to lower temperature can be considered as way to keep growth of milkfish well.

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

Persson, Mats, E-mail: mats.persson@mi.physics.kth

Purpose: The highest photon fluence rate that a computed tomography (CT) detector must be able to measure is an important parameter. The authors calculate the maximum transmitted fluence rate in a commercial CT scanner as a function of patient size for standard head, chest, and abdomen protocols. Methods: The authors scanned an anthropomorphic phantom (Kyoto Kagaku PBU-60) with the reference CT protocols provided by AAPM on a GE LightSpeed VCT scanner and noted the tube current applied with the tube current modulation (TCM) system. By rescaling this tube current using published measurements on the tube current modulation of a GEmore » scanner [N. Keat, “CT scanner automatic exposure control systems,” MHRA Evaluation Report 05016, ImPACT, London, UK, 2005], the authors could estimate the tube current that these protocols would have resulted in for other patient sizes. An ECG gated chest protocol was also simulated. Using measured dose rate profiles along the bowtie filters, the authors simulated imaging of anonymized patient images with a range of sizes on a GE VCT scanner and calculated the maximum transmitted fluence rate. In addition, the 99th and the 95th percentiles of the transmitted fluence rate distribution behind the patient are calculated and the effect of omitting projection lines passing just below the skin line is investigated. Results: The highest transmitted fluence rates on the detector for the AAPM reference protocols with centered patients are found for head images and for intermediate-sized chest images, both with a maximum of 3.4 ⋅ 10{sup 8} mm{sup −2} s{sup −1}, at 949 mm distance from the source. Miscentering the head by 50 mm downward increases the maximum transmitted fluence rate to 5.7 ⋅ 10{sup 8} mm{sup −2} s{sup −1}. The ECG gated chest protocol gives fluence rates up to 2.3 ⋅ 10{sup 8} − 3.6 ⋅ 10{sup 8} mm{sup −2} s{sup −1} depending on miscentering. Conclusions: The fluence rate on a CT detector reaches 3 ⋅ 10{sup 8} − 6 ⋅ 10{sup 8} mm{sup −2} s{sup −1} in standard imaging protocols, with the highest rates occurring for ECG gated chest and miscentered head scans. These results will be useful to developers of CT detectors, in particular photon counting detectors.« less

Using Fish Population Metrics to Compare the Effects of Artificial Reef Density.

PubMed

Froehlich, Catheline Y M; Kline, Richard J

2015-01-01

Artificial reefs continue to be added as habitat throughout the world, yet questions remain about how reef design affects fish diversity and abundance. In the present study, the effects of reef density were assessed for fish communities and sizes of economically valuable Lutjanus campechanus 13 km off Port Mansfield, Texas, at a reef composed of more than 4000 concrete culverts. The study spanned from May to June in 2013 and 2014, and sites sampled included natural reefs, bare areas, and varying culvert patch density categories, ranging from 1-190 culverts. Abundances of adults and species evenness of juvenile populations differed between the years. Fish communities did not significantly differ among density categories; however, highest species richness and total abundances were observed at intermediate culvert densities and at natural reefs. Whereas the abundance of L. campechanus did not differ among density categories, mean total lengths of L. campechanus were greatest at the lower density. Our findings suggest that reefs should be deployed with intermediate patch density of 71-120 culverts in a 30-m radius to yield the highest fish abundances.

Using Fish Population Metrics to Compare the Effects of Artificial Reef Density

PubMed Central

2015-01-01

Artificial reefs continue to be added as habitat throughout the world, yet questions remain about how reef design affects fish diversity and abundance. In the present study, the effects of reef density were assessed for fish communities and sizes of economically valuable Lutjanus campechanus 13 km off Port Mansfield, Texas, at a reef composed of more than 4000 concrete culverts. The study spanned from May to June in 2013 and 2014, and sites sampled included natural reefs, bare areas, and varying culvert patch density categories, ranging from 1–190 culverts. Abundances of adults and species evenness of juvenile populations differed between the years. Fish communities did not significantly differ among density categories; however, highest species richness and total abundances were observed at intermediate culvert densities and at natural reefs. Whereas the abundance of L. campechanus did not differ among density categories, mean total lengths of L. campechanus were greatest at the lower density. Our findings suggest that reefs should be deployed with intermediate patch density of 71–120 culverts in a 30-m radius to yield the highest fish abundances. PMID:26422472

Effects of fresh lubricant oils on particle emissions emitted by a modern gasoline direct injection passenger car.

PubMed

Pirjola, Liisa; Karjalainen, Panu; Heikkilä, Juha; Saari, Sampo; Tzamkiozis, Theodoros; Ntziachristos, Leonidas; Kulmala, Kari; Keskinen, Jorma; Rönkkö, Topi

2015-03-17

Particle emissions from a modern turbocharged gasoline direct injection passenger car equipped with a three-way catalyst and an exhaust gas recirculation system were studied while the vehicle was running on low-sulfur gasoline and, consecutively, with five different lubrication oils. Exhaust particle number concentration, size distribution, and volatility were determined both at laboratory and on-road conditions. The results indicated that the choice of lubricant affected particle emissions both during the cold start and warm driving cycles. However, the contribution of engine oil depended on driving conditions being higher during acceleration and steady state driving than during deceleration. The highest emission factors were found with two oils that had the highest metal content. The results indicate that a 10% decrease in the Zn content of engine oils is linked with an 11-13% decrease to the nonvolatile particle number emissions in steady driving conditions and a 5% decrease over the New European Driving Cycle. The effect of lubricant on volatile particles was even higher, on the order of 20%.

Carbon Nanotubes as Support in the Platinum-Catalyzed Hydrolytic Dehydrogenation of Ammonia Borane.

PubMed

Chen, Wenyao; Duan, Xuezhi; Qian, Gang; Chen, De; Zhou, Xinggui

2015-09-07

We report remarkable support effects for carbon nanotubes (CNTs) in the Pt/CNT-catalyzed hydrolytic dehydrogenation of ammonia borane. The origin of the support-dependent activity and durability is elucidated by combining the catalytic and durability testing with characterization by a range of spectroscopy and high-angle annular dark-field scanning transmission electron microscopy techniques and ICP analysis. The effects mainly arise from different electronic properties and different abilities for the adsorption of boron-containing species on platinum surfaces and changes in size and shape of the platinum particles during the reaction. Defect-rich CNTs in particular are a promising support material, as it not only enhances the platinum binding energy, leading to the highest hydrogen generation rate, but also inhibits the adsorption of boron-containing species and stabilizes the platinum nanoparticles to resist the agglomeration during the reaction, leading to the highest durability. The insights revealed herein may pave the way for the rational design of highly active and durable metal/carbon catalysts for the hydrolytic dehydrogenation of ammonia borane. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The valuation of water quality: effects of mixing different drinking water qualities.

PubMed

Rygaard, Martin; Arvin, Erik; Binning, Philip J

2009-03-01

As water supplies increasingly turn to use desalination technologies it becomes relevant to consider the options for remineralization and blending with mineral rich water resources. We present a method for analyzing economic consequences due to changes in drinking water mineral content. Included impacts are cardiovascular diseases, dental caries, atopic eczema, lifetime of dish and clothes washing machines, heat exchangers, distribution systems, bottled water consumption and soap usage. The method includes an uncertainty assessment that ranks the impacts having the highest influence on the result and associated uncertainty. Effects are calculated for a scenario where 50% of Copenhagen's water supply is substituted by desalinated water. Without remineralization the total impact is expected to be negative (euro -0.44+/-0.2/m(3)) and individual impacts expected in the range of euro 0.01-0.51/m(3) delivered water. Health impacts have the highest contribution to impact size and uncertainty. With remineralization it is possible to reduce several negative impacts and the total impact is expected to be positive (euro 0.14+/-0.08/m(3)).

Advanced TEM characterization of oxide nanoparticles in ODS Fe–12Cr–5Al alloys

DOE PAGES

Unocic, Kinga A; Hoelzer, David T; Pint, Bruce A

2016-01-01

For oxide nanoparticles present in three oxide-dispersion-strengthened (ODS) Fe–12Cr–5Al alloys containing additions of (1) Y 2O 3 (125Y), (2) Y 2O 3 + ZrO 2 (125YZ), and (3) Y 2O 3 + HfO 2 (125YH), were investigated using transmission and scanning transmission electron microscopy. Furthermore, in all three alloys nano-sized (<3.5 nm) oxide particles distributed uniformly throughout the microstructure were characterized using advanced electron microscopy techniques. In the 125Y alloy, mainly Al 2O 3 and yttrium–aluminum garnet (YAG) phases (Y 3Al 5O 12) were present, while in the 125YZ alloy, additional Zr(C,N) precipitates were identified. The 125YH alloy had themore » most complex precipitation sequence whereby in addition to the YAG and Al 2O 3 phases, Hf(C,N), Y 2Hf 2O 7, and HfO 2 precipitates were also found. The presence of HfO 2 was mainly due to the incomplete incorporation of HfO 2 powder during mechanical alloying of the 125YH alloy. The alloy having the highest total number density of the oxides, the smallest grain size, and the highest Vickers hardness was the 125YZ alloy indicating, that Y 2O 3 + ZrO 2 additions had the strongest effect on grain size and tensile properties. Finally, high-temperature mechanical testing will be addressed in the near future, while irradiation studies are underway to investigate the irradiation resistance of these new ODS FeCrAl alloys.« less

Exploring cosmic origins with CORE: Extragalactic sources in cosmic microwave background maps

NASA Astrophysics Data System (ADS)

De Zotti, G.; González-Nuevo, J.; Lopez-Caniego, M.; Negrello, M.; Greenslade, J.; Hernández-Monteagudo, C.; Delabrouille, J.; Cai, Z.-Y.; Bonato, M.; Achúcarro, A.; Ade, P.; Allison, R.; Ashdown, M.; Ballardini, M.; Banday, A. J.; Banerji, R.; Bartlett, J. G.; Bartolo, N.; Basak, S.; Bersanelli, M.; Biesiada, M.; Bilicki, M.; Bonaldi, A.; Bonavera, L.; Borrill, J.; Bouchet, F.; Boulanger, F.; Brinckmann, T.; Bucher, M.; Burigana, C.; Buzzelli, A.; Calvo, M.; Carvalho, C. S.; Castellano, M. G.; Challinor, A.; Chluba, J.; Clements, D. L.; Clesse, S.; Colafrancesco, S.; Colantoni, I.; Coppolecchia, A.; Crook, M.; D'Alessandro, G.; de Bernardis, P.; de Gasperis, G.; Diego, J. M.; Di Valentino, E.; Errard, J.; Feeney, S. M.; Fernández-Cobos, R.; Ferraro, S.; Finelli, F.; Forastieri, F.; Galli, S.; Génova-Santos, R. T.; Gerbino, M.; Grandis, S.; Hagstotz, S.; Hanany, S.; Handley, W.; Hervias-Caimapo, C.; Hills, M.; Hivon, E.; Kiiveri, K.; Kisner, T.; Kitching, T.; Kunz, M.; Kurki-Suonio, H.; Lagache, G.; Lamagna, L.; Lasenby, A.; Lattanzi, M.; Le Brun, A.; Lesgourgues, J.; Lewis, A.; Liguori, M.; Lindholm, V.; Luzzi, G.; Maffei, B.; Mandolesi, N.; Martinez-Gonzalez, E.; Martins, C. J. A. P.; Masi, S.; Massardi, M.; Matarrese, S.; McCarthy, D.; Melchiorri, A.; Melin, J.-B.; Molinari, D.; Monfardini, A.; Natoli, P.; Notari, A.; Paiella, A.; Paoletti, D.; Partridge, R. B.; Patanchon, G.; Piat, M.; Pisano, G.; Polastri, L.; Polenta, G.; Pollo, A.; Poulin, V.; Quartin, M.; Remazeilles, M.; Roman, M.; Rossi, G.; Roukema, B. F.; Rubiño-Martín, J.-A.; Salvati, L.; Scott, D.; Serjeant, S.; Tartari, A.; Toffolatti, L.; Tomasi, M.; Trappe, N.; Triqueneaux, S.; Trombetti, T.; Tucci, M.; Tucker, C.; Väliviita, J.; van de Weygaert, R.; Van Tent, B.; Vennin, V.; Vielva, P.; Vittorio, N.; Young, K.; Zannoni, M.

2018-04-01

We discuss the potential of a next generation space-borne Cosmic Microwave Background (CMB) experiment for studies of extragalactic sources. Our analysis has particular bearing on the definition of the future space project, CORE, that has been submitted in response to ESA's call for a Medium-size mission opportunity as the successor of the Planck satellite. Even though the effective telescope size will be somewhat smaller than that of Planck, CORE will have a considerably better angular resolution at its highest frequencies, since, in contrast with Planck, it will be diffraction limited at all frequencies. The improved resolution implies a considerable decrease of the source confusion, i.e. substantially fainter detection limits. In particular, CORE will detect thousands of strongly lensed high-z galaxies distributed over the full sky. The extreme brightness of these galaxies will make it possible to study them, via follow-up observations, in extraordinary detail. Also, the CORE resolution matches the typical sizes of high-z galaxy proto-clusters much better than the Planck resolution, resulting in a much higher detection efficiency; these objects will be caught in an evolutionary phase beyond the reach of surveys in other wavebands. Furthermore, CORE will provide unique information on the evolution of the star formation in virialized groups and clusters of galaxies up to the highest possible redshifts. Finally, thanks to its very high sensitivity, CORE will detect the polarized emission of thousands of radio sources and, for the first time, of dusty galaxies, at mm and sub-mm wavelengths, respectively.

Effects of Laser Energies on Wear and Tensile Properties of Biomimetic 7075 Aluminum Alloy

NASA Astrophysics Data System (ADS)

Yuan, Yuhuan; Zhang, Peng; Zhao, Guoping; Gao, Yang; Tao, Lixi; Chen, Heng; Zhang, Jianlong; Zhou, Hong

2018-03-01

Inspired by the non-smooth surface of certain animals, a biomimetic coupling unit with various sizes, microstructure, and hardness was prepared on the surface of 7075 aluminum alloy. Following experimental studies were conducted to investigate the wear and tensile properties with various laser energy inputs. The results demonstrated that the non-smooth surface with biomimetic coupling units had a positive effect on both the wear resistance and tensile property of 7075 aluminum alloy. In addition, the sample with the unit fabricated by the laser energy of 420.1 J/cm2 exhibited the most significant improvement on the wear and tensile properties owing to the minimum grain size and the highest microhardness. Also, the weight loss of the sample was one-third of the untreated one's, and the yield strength, the ultimate tensile strength, and the elongation improved by 20, 20, and 34% respectively. Moreover, the mechanisms of wear and tensile properties improvement were also analyzed.

Eu-doped ZnO nanoparticles: Sonochemical synthesis, characterization, and sonocatalytic application.

PubMed

Khataee, Alireza; Karimi, Atefeh; Zarei, Mahmoud; Joo, Sang Woo

2015-03-30

Undoped and europium (III)-doped ZnO nanoparticles were prepared by a sonochemical method. The prepared samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS) analysis. The crystalline sizes of undoped and 3% Eu-doped ZnO were found to be 16.04 and 8.22nm, respectively. The particle size of Eu-doped ZnO nanoparticles was much smaller than that of pure ZnO. The synthesized nanocatalysts were used for the sonocatalytic degradation of Acid Red 17. Among the Eu-doped ZnO catalysts, 3% Eu-doped ZnO nanoparticles showed the highest sonocatalytic activity. The effects of various parameters such as catalyst loading, initial dye concentration, pH, ultrasonic power, the effect of oxidizing agents, and the presence of anions were investigated. The produced intermediates of the sonocatalytic process were monitored by GC-Mass (GC-MS) spectrometry. Copyright © 2015 Elsevier B.V. All rights reserved.

The effect of nanoparticle size on the ability to cross the blood-brain barrier: an in vivo study.

PubMed

Betzer, Oshra; Shilo, Malka; Opochinsky, Renana; Barnoy, Eran; Motiei, Menachem; Okun, Eitan; Yadid, Gal; Popovtzer, Rachela

2017-07-01

Our goal was to develop an efficient nanoparticle-based system that can overcome the restrictive mechanism of the blood-brain barrier (BBB) by targeting insulin receptors and would thus enable drug delivery to the brain. Insulin-coated gold nanoparticles (INS-GNPs) were synthesized to serve as a BBB transport system. The effect of nanoparticle size (20, 50 and 70 nm) on their ability to cross the BBB was quantitatively investigated in Balb/C mice. The most widespread biodistribution and highest accumulation within the brain were observed using 20 nm INS-GNPs, 2 h post injection. In vivo CT imaging revealed that particles migrated to specific brain regions, which are involved in neurodegenerative and neuropsychiatric disorders. These findings promote the optimization of nanovehicles for transport of drugs through the BBB. The insulin coating of the particles enabled targeting of specific brain regions, suggesting the potential use of INS-GNPs for delivery of various treatments for brain-related disorders.

Effect of different-sized colloids on the transport and deposition of titanium dioxide nanoparticles in quartz sand.

PubMed

Cai, Li; Peng, Shengnan; Wu, Dan; Tong, Meiping

2016-01-01

Colloids (non-biological and biological) with different sizes are ubiquitous in natural environment. The investigations regarding the influence of different-sized colloids on the transport and deposition behaviors of engineered-nanoparticles in porous media yet are still largely lacking. This study investigated the effects of different-sized non-biological and biological colloids on the transport of titanium dioxide nanoparticles (nTiO2) in quartz sand under both electrostatically favorable and unfavorable conditions. Fluorescent carboxylate-modified polystyrene latex microspheres (CML) with sizes of 0.2-2 μm were utilized as model non-biological colloids, while Gram-negative Escherichia coli (∼ 1 μm) and Gram-positive Bacillus subtilis (∼ 2 μm) were employed as model biological colloids. Under the examined solution conditions, both breakthrough curves and retained profiles of nTiO2 with different-sized CML particles/bacteria were similar as those without colloids under favorable conditions, indicating that the copresence of model colloids in suspensions had negligible effects on the transport and deposition of nTiO2 under favorable conditions. In contrast, higher breakthrough curves and lower retained profiles of nTiO2 with CML particles/bacteria relative to those without copresent colloids were observed under unfavorable conditions. Clearly, the copresence of model colloids increased the transport and decreased the deposition of nTiO2 in quartz sand under unfavorable conditions (solution conditions examined in present study). Both competition of deposition sites on quartz sand surfaces and the enhanced stability/dispersion of nTiO2 induced by copresent colloids were found to be responsible for the increased nTiO2 transport with colloids under unfavorable conditions. Moreover, the smallest colloids had the highest coverage on sand surface and most significant dispersion effect on nTiO2, resulting in the greatest nTiO2 transport. Copyright © 2015. Published by Elsevier Ltd.

Current Multistage Drug Delivery Systems Based on the Tumor Microenvironment

PubMed Central

Chen, Binlong; Dai, Wenbing; He, Bing; Zhang, Hua; Wang, Xueqing; Wang, Yiguang; Zhang, Qiang

2017-01-01

The development of traditional tumor-targeted drug delivery systems based on EPR effect and receptor-mediated endocytosis is very challenging probably because of the biological complexity of tumors as well as the limitations in the design of the functional nano-sized delivery systems. Recently, multistage drug delivery systems (Ms-DDS) triggered by various specific tumor microenvironment stimuli have emerged for tumor therapy and imaging. In response to the differences in the physiological blood circulation, tumor microenvironment, and intracellular environment, Ms-DDS can change their physicochemical properties (such as size, hydrophobicity, or zeta potential) to achieve deeper tumor penetration, enhanced cellular uptake, timely drug release, as well as effective endosomal escape. Based on these mechanisms, Ms-DDS could deliver maximum quantity of drugs to the therapeutic targets including tumor tissues, cells, and subcellular organelles and eventually exhibit the highest therapeutic efficacy. In this review, we expatiate on various responsive modes triggered by the tumor microenvironment stimuli, introduce recent advances in multistage nanoparticle systems, especially the multi-stimuli responsive delivery systems, and discuss their functions, effects, and prospects. PMID:28255348

Effects of Cooling Conditions on Tensile and Charpy Impact Properties of API X80 Linepipe Steels

NASA Astrophysics Data System (ADS)

Han, Seung Youb; Shin, Sang Yong; Lee, Sunghak; Kim, Nack J.; Bae, Jin-Ho; Kim, Kisoo

2010-02-01

In this study, four API X80 linepipe steel specimens were fabricated by varying the cooling rate and finish cooling temperature, and their microstructures and crystallographic orientations were analyzed to investigate the effects of the cooling conditions on the tensile and Charpy impact properties. All the specimens consisted of acicular ferrite (AF), granular bainite (GB), and martensite-austenite (MA) constituents. The volume fraction of MA increased with an increasing cooling rate, and the volume fraction and size of MA tended to decrease with an increasing finish cooling temperature. According to the crystallographic orientation analysis data, the effective grain size and unit crack path decreased as fine ACs having a large amount of high-angle grain boundaries were homogeneously formed, thereby leading to the improvement in the Charpy impact properties. The specimen fabricated with the higher cooling rate and lower finish cooling temperature had the highest upper-shelf energy (USE) and the lowest energy transition temperature (ETT), because it contained a large amount of MA homogeneously distributed inside fine AFs, while its tensile properties remained excellent.

Current Multistage Drug Delivery Systems Based on the Tumor Microenvironment.

PubMed

Chen, Binlong; Dai, Wenbing; He, Bing; Zhang, Hua; Wang, Xueqing; Wang, Yiguang; Zhang, Qiang

2017-01-01

The development of traditional tumor-targeted drug delivery systems based on EPR effect and receptor-mediated endocytosis is very challenging probably because of the biological complexity of tumors as well as the limitations in the design of the functional nano-sized delivery systems. Recently, multistage drug delivery systems (Ms-DDS) triggered by various specific tumor microenvironment stimuli have emerged for tumor therapy and imaging. In response to the differences in the physiological blood circulation, tumor microenvironment, and intracellular environment, Ms-DDS can change their physicochemical properties (such as size, hydrophobicity, or zeta potential) to achieve deeper tumor penetration, enhanced cellular uptake, timely drug release, as well as effective endosomal escape. Based on these mechanisms, Ms-DDS could deliver maximum quantity of drugs to the therapeutic targets including tumor tissues, cells, and subcellular organelles and eventually exhibit the highest therapeutic efficacy. In this review, we expatiate on various responsive modes triggered by the tumor microenvironment stimuli, introduce recent advances in multistage nanoparticle systems, especially the multi-stimuli responsive delivery systems, and discuss their functions, effects, and prospects.

Coccidian infection may explain the differences in the life history of octopus host populations.

PubMed

Storero, Lorena P; Narvarte, Maite A

2013-11-01

The prevalence of coccidian parasites in three Octopus tehuelchus populations from San Matías Gulf (Patagonia, Argentina) is compared. The prevalence was similar between sexes, but varied between seasons (being highest during cold months) and sites. Islote Lobos had the highest prevalence (42.7-100%) followed by San Antonio Bay (0-66%) and El Fuerte (0-24.5%). Octopuses under 27 mm of dorsal mantle length showed a low prevalence (less than 50%), which increased with size. We hypothesize that the high prevalence of parasites, which affect the three populations differentially, could account for the observed variability in life-span and growth, size-frequency distributions, reproduction and densities of O. tehuelchus populations. Copyright © 2013 Elsevier Inc. All rights reserved.

Size-assortative mating and sexual size dimorphism are predictable from simple mechanics of mate-grasping behavior

PubMed Central

2010-01-01

Background A major challenge in evolutionary biology is to understand the typically complex interactions between diverse counter-balancing factors of Darwinian selection for size assortative mating and sexual size dimorphism. It appears that rarely a simple mechanism could provide a major explanation of these phenomena. Mechanics of behaviors can predict animal morphology, such like adaptations to locomotion in animals from various of taxa, but its potential to predict size-assortative mating and its evolutionary consequences has been less explored. Mate-grasping by males, using specialized adaptive morphologies of their forelegs, midlegs or even antennae wrapped around female body at specific locations, is a general mating strategy of many animals, but the contribution of the mechanics of this wide-spread behavior to the evolution of mating behavior and sexual size dimorphism has been largely ignored. Results Here, we explore the consequences of a simple, and previously ignored, fact that in a grasping posture the position of the male's grasping appendages relative to the female's body is often a function of body size difference between the sexes. Using an approach taken from robot mechanics we model coercive grasping of females by water strider Gerris gracilicornis males during mating initiation struggles. We determine that the male optimal size (relative to the female size), which gives the males the highest grasping force, properly predicts the experimentally measured highest mating success. Through field sampling and simulation modeling of a natural population we determine that the simple mechanical model, which ignores most of the other hypothetical counter-balancing selection pressures on body size, is sufficient to account for size-assortative mating pattern as well as species-specific sexual dimorphism in body size of G. gracilicornis. Conclusion The results indicate how a simple and previously overlooked physical mechanism common in many taxa is sufficient to account for, or importantly contribute to, size-assortative mating and its consequences for the evolution of sexual size dimorphism. PMID:21092131

77 FR 10724 - Western Pacific Pelagic Fisheries; American Samoa Longline Limited Entry Program

Federal Register 2010, 2011, 2012, 2013, 2014

2012-02-23

... size class falls below the maximum allowed. Six permits are available, as follows: Four in Class A (vessels less than or equal to 40 ft in overall length); and Two in Class D (over 70 ft in overall length... the highest priority to the applicant (for any vessel size class) with the earliest documented...

Optimum Conditions for Preparation of High-Performance (Ba0.97Ca0.03)(Ti0.94Sn0.06)O3 Ceramics by Solid-State Combustion

NASA Astrophysics Data System (ADS)

Chootin, Suphornphun; Bongkarn, Theerachai

2017-08-01

The effects of calcination conditions (950°C to 1200°C for 2 h to 6 h) and sintering temperature (1300°C to 1500°C for 2 h) on phase formation, microstructure, and electrical behavior of lead-free piezoelectric (Ba0.97Ca0.03)(Ti0.94Sn0.06)O3 (BCTS) ceramics produced by solid-state combustion using glycine as fuel have been investigated. BCTS powder with pure perovskite structure was obtained by calcination at 1100°C for 4 h. The microstructure of the BCTS powders showed almost spherical shape with average particle size increasing from 184 nm to 320 nm as the calcination temperature and soaking time were increased. The XRD patterns of all ceramics exhibited single perovskite structure. Rietveld refinement analysis indicated that the BCTS ceramics exhibited coexistence of orthorhombic and tetragonal phase in all samples with increased tetragonal phase content with increasing sintering temperature. The average grain size, density, dielectric constants at room ( ɛ r) and Curie temperature ( ɛ C), remanent polarization ( P r), and piezoelectric constant ( d 33) increased as the sintering temperature was increased up to 1400°C, then decreased. BCTS ceramic sintered at 1400°C exhibited the highest relative density (98%), highest dielectric response ( ɛ r = 4951, ɛ C = 19,185), good ferroelectric behavior ( P r = 12.74 μC/cm2 and coercive field E c = 1.60 kV/cm), and highest d 33 value (528 pC/N). The large piezoelectricity of BCTS ceramics makes them good candidates for use in lead-free applications to replace Pb-based ceramics.

Analysis of heavy metals in road-deposited sediments.

PubMed

Herngren, Lars; Goonetilleke, Ashantha; Ayoko, Godwin A

2006-07-07

Road-deposited sediments were analysed for heavy metal concentrations at three different landuses (residential, industrial, commercial) in Queensland State, Australia. The sediments were collected using a domestic vacuum cleaner which was proven to be highly efficient in collecting sub-micron particles. Five particle sizes were analysed separately for eight heavy metal elements (Zn, Fe, Pb, Cd, Cu, Cr, Al and Mn). At all sites, the maximum concentration of the heavy metals occurred in the 0.45-75 microm particle size range, which conventional street cleaning services do not remove efficiently. Multicriteria decision making methods (MCDM), PROMETHEE and GAIA, were employed in the data analysis. PROMETHEE, a non-parametric ranking analysis procedure, was used to rank the metal contents of the sediments sampled at each site. The most polluted site and particle size range were the industrial site and the 0.45-75 microm range, respectively. Although the industrial site displayed the highest metal concentrations, the highest heavy metal loading coincided with the highest sediment load, which occurred at the commercial site. GAIA, a special form of principal component analysis, was applied to determine correlations between the heavy metals and particle size ranges and also to assess possible correlation with total organic carbon (TOC). The GAIA-planes revealed that irrespective of the site, most of the heavy metals are adsorbed to sediments below 150 microm. A weak correlation was found between Zn, Mn and TOC at the commercial site. This could lead to higher bioavailability of these metals through complexation reactions with the organic species in the sediments.

Effects of daily energy expenditure on academic performance of elementary students in Taiwan.

PubMed

Wang, Peng-Sheng; Huang, Yi-Ching; Wu, Shu-Fang Vivienne; Wang, Kuo-Ming

2014-01-01

The objective of the study was to investigate the potential effects of daily energy expenditure on the academic performance (AP) of elementary schoolchildren, the results of which will be used as the basis of planning physical activity (PA) for children in the future. Participants were collected from 4th to 6th grade children at an elementary school in southern Taiwan. The effective sample data size was 1065 (79.8%; 528 boys and 537 girls). Daily mean energy expenditure was obtained using the 3 Day Physical Activity Recall (3-DPAR), and the intensive activities degrees of physical activity were categorized into lowest PA, middle PA, and highest PA group, and academic performance assessed with weighted academic score. The significant effect on the academic performance of schoolchildren was only in energy expenditure but not for sexes and tutorials attended. All students in the middle PA group performed better academically than those in the highest PA group. After controlling sexes, male students in the middle PA group performed better than other groups; female students in the lowest PA group performed better than other groups. These results may be consulted by schools, academic faculties, and parents in setting up exercise plans for children. © 2012 The Authors. Japan Journal of Nursing Science © 2012 Japan Academy of Nursing Science.

Skeletal anomaly assessment in diploid and triploid juvenile Atlantic salmon (Salmo salar L.) and the effect of temperature in freshwater.

PubMed

Amoroso, G; Adams, M B; Ventura, T; Carter, C G; Cobcroft, J M

2016-04-01

Triploid Atlantic salmon tend to develop a higher prevalence of skeletal anomalies. This tendency may be exacerbated by an inadequate rearing temperature. Early juvenile all-female diploid and triploid Atlantic salmon were screened for skeletal anomalies in consecutive experiments to include two size ranges: the first tested the effect of ploidy (0.2-8 g) and the second the effect of ploidy, temperature (14 °C and 18 °C) and their interaction (8-60 g). The first experiment showed that ploidy had no effect on skeletal anomaly prevalence. A high prevalence of opercular shortening was observed (average prevalence in both ploidies 85.8%) and short lower jaws were common (highest prevalence observed 11.3%). In the second experiment, ploidy, but not temperature, affected the prevalence of short lower jaw (diploids > triploids) and lower jaw deformity (triploids > diploids, highest prevalence observed 11.1% triploids and 2.7% diploids) with a trend indicating a possible developmental link between the two jaw anomalies in triploids. A radiological assessment (n = 240 individuals) showed that at both temperatures triploids had a significantly (P < 0.05) lower number of vertebrae and higher prevalence of deformed individuals. These findings (second experiment) suggest ploidy was more influential than temperature in this study. © 2016 John Wiley & Sons Ltd.

Development of a terrestrial vertebrate model for assessing bioavailability of cadmium in the fence lizard (Sceloporus undulatus) and in ovo effects on hatchling size and thyroid function.

PubMed

Brasfield, Sandra M; Bradham, Karen; Wells, Jason B; Talent, Larry G; Lanno, Roman P; Janz, David M

2004-03-01

In the terrestrial environment, standardized protocols are available for measuring the exposure and effects of contaminants to invertebrates, but none currently exist for vertebrates. In an effort to address this, we proposed that developing lizard embryos may be used as a terrestrial vertebrate model. Lizard eggs may be particularly susceptible to soil contamination and in ovo exposure may affect hatchling size, mortality, as well as thyroid function. Toxicant-induced perturbations of thyroid function resulting from in ovo chemical exposure may result in toxicity during the critical perinatal period in reptiles. Fertilized Eastern fence lizard (Sceloporus undulatus) eggs were placed in cadmium (Cd)-spiked expanded perlite (0, 1.48, 14.8, 148, 1480, 14,800 microg Cd/g, nominal concentrations), artificially incubated at 28 degrees C, and examined daily for mortality. Whole lizard hatchlings as well as failed hatches were homogenized in ethanol and the homogenate was divided for Cd body residue analysis and thyroid hormone (triiodothyronine (T3) and thyroxine (T4)) analyses. Acute mortality was observed in the two highest doses (1480 and 14800 microg Cd/g). Cadmium body residues showed a higher internal concentration with increasing exposure concentration indicating uptake of Cd. There was a decrease in T3:T4 ratio at the highest surviving dose (148 microg Cd/g), however, there were no differences observed in hatchling size measured as weight and snout-vent length, or in whole body thyroid hormone levels. In summary, this study has shown Cd amended to a solid phase representing soil (perlite) can traverse the thin, parchment-like shell membrane of the fence lizard egg and bioaccumulate in lizard embryos. We believe this study is a good first step in investigating and evaluating this species for use as a model.

Relationship between metallothioneins and metals in a natural population of the clam Ruditapes decussatus from Sfax coast: a non-linear model using Box-Cox transformation.

PubMed

Hamza-Chaffai, A; Amiard, J C; Cosson, R P

1999-06-01

Cadmium, copper and zinc were determined concomitantly with metallothionein-like proteins (MTLPs) in the subcellular fractions of Ruditapes decussatus digestive gland. This study covered 4 months and aimed to evaluate the effect of metal pollution and other factors such as sex, size and reproductive state on MTLP levels. Copper concentrations did not vary with month, however Cd and Zn concentrations showed high levels during August. Organisms showing low cadmium concentrations presented the highest cadmium percentages in the soluble fraction (SF) containing MTLPs. However for high cadmium concentrations, the insoluble fraction (IF) was implicated in cadmium association. MTLP levels varied according to the month, the sex and the size of the organisms. A non-linear model based on the Box-Cox transformation, was proposed to describe a positive and a significant relationship between MTLPs and the studied metals. A model including sex and size showed that these two factors affected MTLP levels, but were less important than metals. Males of R. decussatus showed higher significant correlations between MTLP levels and cadmium than females. Moreover, the effect of size and reproductive state on MTLP levels was less perceptible in males than in females. As a result, MTLPs in males of R. decussatus could be proposed as suitable biomarker for detecting metal contamination.

Pore diffusion limits removal of monochloramine in treatment of swimming pool water using granular activated carbon.

PubMed

Skibinski, Bertram; Götze, Christoph; Worch, Eckhard; Uhl, Wolfgang

2018-04-01

Overall apparent reaction rates for the removal of monochloramine (MCA) in granular activated carbon (GAC) beds were determined using a fixed-bed reactor system and under conditions typical for swimming pool water treatment. Reaction rates dropped and quasi-stationary conditions were reached quickly. Diffusional mass transport in the pores was shown to be limiting the overall reaction rate. This was reflected consistently in the Thiele modulus, in the effect of temperature, pore size distribution and of grain size on the reaction rates. Pores <2.5 times the diameter of the monochloramine molecule were shown to be barely accessible for the monochloramine conversion reaction. GACs with a significant proportion of large mesopores were found to have the highest overall reactivity for monochloramine removal. Copyright © 2017 Elsevier Ltd. All rights reserved.

Studies on post weld heat treatment of dissimilar aluminum alloys by laser beam welding technique

NASA Astrophysics Data System (ADS)

Srinivas, B.; Krishna, N. Murali; Cheepu, Muralimohan; Sivaprasad, K.; Muthupandi, V.

2018-03-01

The present study mainly focuses on post weld heat treatment (PWHT) of AA5083 and AA6061 alloys by joining these using laser beam welding at three different laser power and two different beam spot sizes and three different welding speeds. Effects of these parameters on microstructural and mechanical properties like hardness, tensile strength were studied at PWHT condition and significant changes had been observed. The PWHT used was artificial aging technique. The microstructural observations revealed that there was a appreciable changes were taken place in the grain size. The microhardness observations proven that the change in the hardness profile in AA6061 was appreciable than in the AA5083. The tensile strength of 246 MPa was recorded as highest. The fractured surfaces observed are predominantly ductile in nature.

Central composite rotatable design for investigation of microwave-assisted extraction of ginger (Zingiber officinale)

NASA Astrophysics Data System (ADS)

Fadzilah, R. Hanum; Sobhana, B. Arianto; Mahfud, M.

2015-12-01

Microwave-assisted extraction technique was employed to extract essential oil from ginger. The optimal condition for microwave assisted extraction of ginger were determined by resposnse surface methodology. A central composite rotatable design was applied to evaluate the effects of three independent variables. The variables is were microwave power 400 - 800W as X1, feed solvent ratio of 0.33 -0.467 as X2 and feed size 1 cm, 0.25 cm and less than 0.2 cm as X3. The correlation analysis of mathematical modelling indicated that quadratic polynomial could be employed to optimize microwave assisted extraction of ginger. The optimal conditions to obtain highest yield of essential oil were : microwave power 597,163 W : feed solvent ratio and size of feed less than 0.2 cm.

Seasonally different reproductive investment in a medium-sized rodent (Cavia aperea).

PubMed

Rübensam, K; Hribal, R; Jewgenow, K; Guenther, A

2015-09-01

Pronounced seasonal variations in day length, temperature, and resource availability characterize the temperate regions and strongly influence the animals living in these environments. To survive and reproduce successfully, animals must allocate resources among competing physiological systems, and they usually adjust their time of breeding to the most adequate season. Here, we examined whether reproductive investment in the wild guinea pig (Cavia aperea) differs across seasons. We kept animals in combined indoor-outdoor enclosures under natural light and temperature year-round. We measured littering probability, litter size, and birth weight, as well as maternal weight loss during lactation. In addition, we measured ovulation rate as a parameter to adjust reproductive investment prenatally. Our data reveal strong seasonal variations in reproductive traits despite the fact that the animals reproduced year-round. The results show a reduced reproductive investment in winter, indicated by a lower litter size and birth weight of pups, whereas investment was highest in warm seasons (summer and autumn) with higher litter size and birth weight. Maternal weight loss in lactation was highest in cold seasons even if the litter size was lower. Furthermore, we found the regulation on the proximate level of the reproductive investment, the ovulation rate, to differ significantly between the seasons. Copyright © 2015 Elsevier Inc. All rights reserved.

Metal accumulation in the greentail prawn, Metapenaeus bennettae, in Sydney and Port Hacking estuaries, Australia.

PubMed

Lewtas, K L M; Birch, G F; Foster-Thorpe, C

2014-01-01

Metal concentrations of the inshore greentail prawn, Metapenaeus bennettae, and surface sediments from locations within Sydney estuary and Port Hacking (Australia) were assessed for bioaccumulation and contamination. The current study aimed to assess metal concentrations in prawn tissue (tail muscle, exoskeleton, hepatopancreas and gills), relate whole body prawn tissue metal concentrations to sediment metal concentrations and animal size, as well as assess prawn consumption as a risk to human health. Metal concentrations were highest in sediment and prawns from contaminated locations (Iron Cove, Hen and Chicken Bay and Lane Cove) in Sydney estuary compared with the reference estuary (Port Hacking). Concentrations in sediments varied considerably between sites and between metals (As, Cd, Cr, Cu, Ni, Pb and Zn), and although concentrations exceeded Interim Sediment Quality Guideline-Low values, metals (As, Cd, Cr, Cu, Ni, Pb and Zn) were below Australian National Health and Medical Research Council human consumption guidelines in prawn tail muscle tissue. Metal concentrations in prawn tail muscle tissue were significantly different (p ≤ 0.05) amongst locations for Pb, Zn and Cd, and metal concentrations were generally highest in gills tissue, followed by the hepatopancreas, exoskeleton and tail muscle. The exoskeleton contained the highest Sr concentration; the hepatopancreas contained the highest As, Cu and Mo concentrations; and the gills contained the highest Al, Cr, Fe and Pb concentrations. Concentrations of Pb, As and Sr were significantly different (p ≤ 0.05) between size groups amongst locations.

Analysis of variables affecting unemployment rate and detecting for cluster in West Java, Central Java, and East Java in 2012

NASA Astrophysics Data System (ADS)

Samuel, Putra A.; Widyaningsih, Yekti; Lestari, Dian

2016-02-01

The objective of this study is modeling the Unemployment Rate (UR) in West Java, Central Java, and East Java, with rate of disease, infant mortality rate, educational level, population size, proportion of married people, and GDRP as the explanatory variables. Spatial factors are also considered in the modeling since the closer the distance, the higher the correlation. This study uses the secondary data from BPS (Badan Pusat Statistik). The data will be analyzed using Moran I test, to obtain the information about spatial dependence, and using Spatial Autoregressive modeling to obtain the information, which variables are significant affecting UR and how great the influence of the spatial factors. The result is, variables proportion of married people, rate of disease, and population size are related significantly to UR. In all three regions, the Hotspot of unemployed will also be detected districts/cities using Spatial Scan Statistics Method. The results are 22 districts/cities as a regional group with the highest unemployed (Most likely cluster) in the study area; 2 districts/cities as a regional group with the highest unemployed in West Java; 1 district/city as a regional groups with the highest unemployed in Central Java; 15 districts/cities as a regional group with the highest unemployed in East Java.

Association between excess weight and beverage portion size consumed in Brazil

PubMed Central

Bezerra, Ilana Nogueira; de Alencar, Eudóxia Sousa

2018-01-01

ABSTRACT OBJECTIVE To describe the beverage portion size consumed and to evaluate their association with excess weight in Brazil. METHODS We used data from the National Dietary Survey, which included individuals with two days of food record aged over 20 years (n = 24,527 individuals). The beverages were categorized into six groups: soft drink, 100% fruit juice, fruit drink, alcoholic beverage, milk, and coffee or tea. We estimated the average portion consumed for each group and we evaluated, using linear regression, the association between portion size per group and the variables of age, sex, income, and nutritional status. We tested the association between portion size and excess weight using Poisson regression, adjusted for age, sex, income, and total energy intake. RESULTS The most frequently consumed beverages in Brazil were coffee and tea, followed by 100% fruit juices, soft drinks, and milk. Alcoholic beverages presented the highest average in the portion size consumed, followed by soft drinks, 100% fruit juice, fruit drink, and milk. Portion size showed positive association with excess weight only in the soft drink (PR = 1.19, 95%CI 1.10–1.27) and alcoholic beverage groups (PR = 1.20, 95%CI, 1.11–1.29), regardless of age, sex, income, and total energy intake. CONCLUSIONS Alcoholic beverages and soft drinks presented the highest averages in portion size and positive association with excess weight. Public health interventions should address the issue of portion sizes offered to consumers by discouraging the consumption of large portions, especially sweetened and low nutritional beverages. PMID:29489988

Hyaluronic acid-functionalized polymeric nanoparticles for colon cancer-targeted combination chemotherapy

NASA Astrophysics Data System (ADS)

Xiao, Bo; Han, Moon Kwon; Viennois, Emilie; Wang, Lixin; Zhang, Mingzhen; Si, Xiaoying; Merlin, Didier

2015-10-01

Nanoparticle (NP)-based combination chemotherapy has been proposed as an effective strategy for achieving synergistic effects and targeted drug delivery for colon cancer therapy. Here, we fabricated a series of hyaluronic acid (HA)-functionalized camptothecin (CPT)/curcumin (CUR)-loaded polymeric NPs (HA-CPT/CUR-NPs) with various weight ratios of CPT to CUR (1 : 1, 2 : 1 and 4 : 1). The resultant spherical HA-CPT/CUR-NPs had a desirable particle size (around 289 nm), relative narrow size distribution, and slightly negative zeta potential. These NPs exhibited a simultaneous sustained release profile for both drugs throughout the time frame examined. Subsequent cellular uptake experiments demonstrated that the introduction of HA to the NP surface endowed NPs with colon cancer-targeting capability and markedly increased cellular uptake efficiency compared with chitosan-coated NPs. Importantly, the combined delivery of CPT and CUR in one HA-functionalized NP exerted strong synergistic effects. HA-CPT/CUR-NP (1 : 1) showed the highest antitumor activity among the three HA-CPT/CUR-NPs, resulting in an extremely low combination index. Collectively, our findings indicate that this HA-CPT/CUR-NP can be exploited as an efficient formulation for colon cancer-targeted combination chemotherapy.Nanoparticle (NP)-based combination chemotherapy has been proposed as an effective strategy for achieving synergistic effects and targeted drug delivery for colon cancer therapy. Here, we fabricated a series of hyaluronic acid (HA)-functionalized camptothecin (CPT)/curcumin (CUR)-loaded polymeric NPs (HA-CPT/CUR-NPs) with various weight ratios of CPT to CUR (1 : 1, 2 : 1 and 4 : 1). The resultant spherical HA-CPT/CUR-NPs had a desirable particle size (around 289 nm), relative narrow size distribution, and slightly negative zeta potential. These NPs exhibited a simultaneous sustained release profile for both drugs throughout the time frame examined. Subsequent cellular uptake experiments demonstrated that the introduction of HA to the NP surface endowed NPs with colon cancer-targeting capability and markedly increased cellular uptake efficiency compared with chitosan-coated NPs. Importantly, the combined delivery of CPT and CUR in one HA-functionalized NP exerted strong synergistic effects. HA-CPT/CUR-NP (1 : 1) showed the highest antitumor activity among the three HA-CPT/CUR-NPs, resulting in an extremely low combination index. Collectively, our findings indicate that this HA-CPT/CUR-NP can be exploited as an efficient formulation for colon cancer-targeted combination chemotherapy. Electronic supplementary information (ESI) available: Representative flow cytometry plots of cells incubated with or without cationic CPT/CUR-NPs (1 : 1) for 3 h; Cytotoxicity of blank chitosan-coated NPs and blank HA-functionalized NPs at different concentrations against Colon-26 cells after 48 h of co-incubation. See DOI: 10.1039/c5nr04831a

The effects of wood dusts on the redox status and cell death in mouse macrophages (RAW 264.7) and human leukocytes in vitro.

PubMed

Naarala, J; Kasanen, J-P; Pasanen, P; Pasanen, A-L; Liimatainen, A; Pennanen, S; Liesivuori, J

2003-07-11

Wood dusts are classified as carcinogenic to humans and also produce other toxic, allergic, and acute effects in woodworkers. However, little is known about causative agents in wood dusts and their mechanisms of action. The effects of different tree species and particle size for biological activity were studied. The differences in the production of reactive oxygen species (ROS) and cell death (necrotic and apoptotic) between mouse macrophage (RAW 264.7) cells and human polymorphonuclear leukocytes (PMNL) for pine, birch, and beech dust exposures were investigated in vitro. The pine and birch dust exposure (1-100 microg/ml) produced concentration-dependent ROS production in both the cells, which was one order of magnitude higher with pine dust. The ROS production was faster in human PNML than murine RAW cells. The higher concentrations (500 and/or 1000 microg/ml) decreased ROS formation. With pine and birch dust exposure, this was probably due to the necrotic cell death. The pine dust concentrations of 500 and 1000 microg/ml were cytotoxic to human PMNL. The beech dust exposure activated the ROS production and decreased the cell viability only at the highest concentrations, being least potent of the three dusts. A sign of the apoptotic cell death in the murine RAW cells was observed at the pine dust concentration of 100 microg/ml. The exposure to the birch and beech dusts with a smaller particle size (<5 microm) produced greater ROS production than exposure to the corresponding dust with a wide range of particle sizes. However, changing the particle size did not affect the cell viability. The results indicate that the type of wood dust (tree species and possibly particle size) has a significant impact on the function and viability of phagocytic cells.

Sympathy for the Devil: Detailing the Effects of Planning-Unit Size, Thematic Resolution of Reef Classes, and Socioeconomic Costs on Spatial Priorities for Marine Conservation

PubMed Central

Pressey, Robert L.; Weeks, Rebecca; Andréfouët, Serge; Moloney, James

2016-01-01

Spatial data characteristics have the potential to influence various aspects of prioritising biodiversity areas for systematic conservation planning. There has been some exploration of the combined effects of size of planning units and level of classification of physical environments on the pattern and extent of priority areas. However, these data characteristics have yet to be explicitly investigated in terms of their interaction with different socioeconomic cost data during the spatial prioritisation process. We quantify the individual and interacting effects of three factors—planning-unit size, thematic resolution of reef classes, and spatial variability of socioeconomic costs—on spatial priorities for marine conservation, in typical marine planning exercises that use reef classification maps as a proxy for biodiversity. We assess these factors by creating 20 unique prioritisation scenarios involving combinations of different levels of each factor. Because output data from these scenarios are analogous to ecological data, we applied ecological statistics to determine spatial similarities between reserve designs. All three factors influenced prioritisations to different extents, with cost variability having the largest influence, followed by planning-unit size and thematic resolution of reef classes. The effect of thematic resolution on spatial design depended on the variability of cost data used. In terms of incidental representation of conservation objectives derived from finer-resolution data, scenarios prioritised with uniform cost outperformed those prioritised with variable cost. Following our analyses, we make recommendations to help maximise the spatial and cost efficiency and potential effectiveness of future marine conservation plans in similar planning scenarios. We recommend that planners: employ the smallest planning-unit size practical; invest in data at the highest possible resolution; and, when planning across regional extents with the intention of incidentally representing fine-resolution features, prioritise the whole region with uniform costs rather than using coarse-resolution data on variable costs. PMID:27829042

Sympathy for the Devil: Detailing the Effects of Planning-Unit Size, Thematic Resolution of Reef Classes, and Socioeconomic Costs on Spatial Priorities for Marine Conservation.

PubMed

Cheok, Jessica; Pressey, Robert L; Weeks, Rebecca; Andréfouët, Serge; Moloney, James

2016-01-01

Spatial data characteristics have the potential to influence various aspects of prioritising biodiversity areas for systematic conservation planning. There has been some exploration of the combined effects of size of planning units and level of classification of physical environments on the pattern and extent of priority areas. However, these data characteristics have yet to be explicitly investigated in terms of their interaction with different socioeconomic cost data during the spatial prioritisation process. We quantify the individual and interacting effects of three factors-planning-unit size, thematic resolution of reef classes, and spatial variability of socioeconomic costs-on spatial priorities for marine conservation, in typical marine planning exercises that use reef classification maps as a proxy for biodiversity. We assess these factors by creating 20 unique prioritisation scenarios involving combinations of different levels of each factor. Because output data from these scenarios are analogous to ecological data, we applied ecological statistics to determine spatial similarities between reserve designs. All three factors influenced prioritisations to different extents, with cost variability having the largest influence, followed by planning-unit size and thematic resolution of reef classes. The effect of thematic resolution on spatial design depended on the variability of cost data used. In terms of incidental representation of conservation objectives derived from finer-resolution data, scenarios prioritised with uniform cost outperformed those prioritised with variable cost. Following our analyses, we make recommendations to help maximise the spatial and cost efficiency and potential effectiveness of future marine conservation plans in similar planning scenarios. We recommend that planners: employ the smallest planning-unit size practical; invest in data at the highest possible resolution; and, when planning across regional extents with the intention of incidentally representing fine-resolution features, prioritise the whole region with uniform costs rather than using coarse-resolution data on variable costs.

Preparation and the in vitro evaluation of nanoemulsion system for the transdermal delivery of granisetron hydrochloride.

PubMed

Zheng, Wen-wu; Zhao, Ling; Wei, Yu-meng; Ye, Yun; Xiao, Shun-han

2010-08-01

The objective of this study was to develop and evaluate nanoemulsion system for transdermal delivery of granisetron hydrochloride. Pseudo-ternary phase diagram was constructed to ascertain the concentration range of components of nanoemulsion composed of isopropyl myristate (IPM) as an oil phase, tween 85 as surfactant, ethanol as cosurfactant, water as aqueous phase. The effects of the content of IPM as an oil phase and n-methyl pyrrolidone (NMP) as transdermal enhancer on rat skin permeation of granisetron hydrochloride nanoemulsion were studied in vitro. The results showed that the mean particle size of nanoemulsion ranged from 50.4+/-1.5 to 82.4+/-0.9 nm with homogeneous size distribution. The resulted optimum formulation composed of 2.5% granisetron hydrochloride, 4% IPM, 40% tween 85/ethanol (1 : 1) and 10% NMP showed that the skin permeation rate was the highest (85.39+/-2.90 microg/cm(2)/h) and enhancement of drug permeability was 4.1-fold for transdermal delivery of granisetron hydrochloridein comparison with the control group (20% of tween 85 and 20% of ethanol micelle solution containing 2.5% of granisetron hydrochloride without IPM), and cumulative permeation amount was the highest (891.8+/-2.86 microg/cm(2)) with the shortest lag time (0.11+/-0.02 h) and was stable for at least 12 months. Therefore, the nanoemulsion system developed in this study offers a promising vehicle for the transdermal delivery system of granisetron hydrochloride, which may be as effective as oral or intravenous dosage forms and avoid some difficulties associated with these dosage forms.

Effects of spray drying and size reduction of edible bird's nest on in-vitro digestibility

NASA Astrophysics Data System (ADS)

Muslim, Masitah; Babji, Abdul Salam; Mustapha, Wan Aida Wan

2015-09-01

The purpose of this study is to determine the effects of spray drying and size reduction of edible bird's nest (EBN) on in-vitro digestibility respectively. Sample prepared were EBN microparticulates; 710 µm (EBN710), 300 µm (EBN300) and 38 µm (EBN38), EBN spray died (EBNSD) and raw EBN (EBNraw) as control. Protein content and solubility were determined before the samples being subjected to in-vitro digestibility. Protein content of EBN710 (55.37±0.269%), EBN300 (56.57±0.163%) EBN38 (56.77±0.021%) and EBNraw (55.46±0.269%) was not significantly different (p>0.05) but EBNSD (60.33b+0.346%) was the highest (p<0.05). Solubility results showed that EBNSD had the highest solubility (94.38±1.24%) in water significantly (p<0.05) compared to EBNraw (16.01±0.231%), EBN710 (21.89+0.41%), EBN300 (22.52+0.072%) and EBN38 (27.51±0.321%). Digestibility of EBN300 (88.43±0.95%) was higher (p<0.05) compared to EBNSD (85.23±0.27%). However, treatment of microparticulates and spray drying were not significantly different with EBNraw (85.38±1.12%). Digestibility of EBN microparticulates and spray dried powder were all lower (p<0.05) than casein (98.36+0.95%). Lower EBN digestibility could be due to the nature of EBN protein as glycoprotein. Proteolytic (tryptic) digestion of native glycoprotein is often incomplete due to ste aric hindrance from the presence of bulky oligosaccharides.

Theoretical investigation of performance of armchair graphene nanoribbon field effect transistors

NASA Astrophysics Data System (ADS)

Hur, Ji-Hyun; Kim, Deok-Kee

2018-05-01

In this paper, we theoretically investigate the highest possible expected performance for graphene nanoribbon field effect transistors (GNRFETs) for a wide range of operation voltages and device structure parameters, such as the width of the graphene nanoribbon and gate length. We formulated a self-consistent, non-equilibrium Green’s function method in conjunction with the Poisson equation and modeled the operation of nanometer sized GNRFETs, of which GNR channels have finite bandgaps so that the GNRFET can operate as a switch. We propose a metric for competing with the current silicon CMOS high performance or low power devices and explain that this can vary greatly depending on the GNRFET structure parameters.

Theoretical investigation of performance of armchair graphene nanoribbon field effect transistors.

PubMed

Hur, Ji-Hyun; Kim, Deok-Kee

2018-05-04

In this paper, we theoretically investigate the highest possible expected performance for graphene nanoribbon field effect transistors (GNRFETs) for a wide range of operation voltages and device structure parameters, such as the width of the graphene nanoribbon and gate length. We formulated a self-consistent, non-equilibrium Green's function method in conjunction with the Poisson equation and modeled the operation of nanometer sized GNRFETs, of which GNR channels have finite bandgaps so that the GNRFET can operate as a switch. We propose a metric for competing with the current silicon CMOS high performance or low power devices and explain that this can vary greatly depending on the GNRFET structure parameters.

[Polychlorinated biphenyls in fractions of wheat grains and in selected bakery products].

PubMed

Brandt, Elzbieta; Pietrzak-Fiećko, Renata; Smoczyński, S S

2012-01-01

Polychlorinated biphenyls (PCBs) form a group of synthetic aromatic chemical compounds, commonly occurring in the environment as a result of industrialisation. Despite the ban on PCBs production, their wide application in the past resulted in their common occurrence in all elements of the environment. The lipophilic nature of the compounds resulting in their accumulation in live organisms and in the human body may trigger many harmful effects. The aim of this study was to determine the PCBs content in the selected species of wheat and in bakery products. The studies aiming at confirming possible correlation between the size of the grain of the selected species of wheat and the content of polychlorinated biphenyls were presented in this paper. Moreover, PCBs concentration in cereals' grains and in bread was compared. The PCBs content was defined in different sizes of grains species of wheat i.e. Opatka, Zyta, Elena and Almari. The study included also two kinds of wheat bread. PCBs were determined after the extraction with n-hexane followed by sulphuric acid hydrolysis. Gas chromatography analysis was conducted on a PU 4600 Unicam apparatus with an electron capture detector. The large variations in PCBs content depending on the grain size were confirmed. In the Opatka species the increase in the content of all determined congeners and the size of grain was confirmed. The lowest PCBs concentrations were in smallest grains (0,0090 mg/kg of fat), and the highest in the largest grains (0,0264 mg/kg of fat). In Zyta species PCBs content was also lowest in the smallest grains, however these results were not statistically significant. In the Elena species the increase in the PCBs content together with the increase in the grain size was confirmed. Basing on the determination coefficient it was found that the concentration of PCBs depends on the size of grains in 24%. The highest concentration of PCBs (0,0366 mg/kg of fat) was found in the largest grains, however differences between the examined fractions were not statistically significant. Similar tendencies were observed in Almari species. PCBs content in wheat bread was on lower level than in all of the examined species. It was confirmed that fraction 2,8 x 25 mm of all species of wheat grain had the highest PCBs content. The tendency to decrease of PCBs content with the decrease of the grain in size was observed. The relation between qualitative class of species and PCBs content was not confirmed. There were statistically significant differences in the PCBs concentrations between the wheat species within one size fraction. The results of PCBs content in wheat bread were lower than in all examined species of wheat. One can assume that for the production of bread collected for the study, the wheat originating from areas with low PCBs contamination was used. Somewhat higher PCBs content was observed in the wheat bread with bran added, probably due to higher PCBs accumulation in the bran, which contain higher fat and contribute therefore to the overall PCBs in the bran containing bread.

Treatment of port wine stains with pulsed dye laser: a retrospective study of 848 cases in Shandong Province, People’s Republic of China

PubMed Central

Shi, Wenhao; Wang, Jinliang; Lin, Yan; Geng, Jianhui; Wang, Haixia; Gong, Yueqin; Liu, Huaxu; Zhang, Furen

2014-01-01

Background Currently, 595 nm pulsed dye laser (PDL) therapy is offered as one of the effective treatments of port wine stains (PWSs). However, the efficacy of PDL differs in different populations. Objective The purpose of the study was to investigate the efficacy, and related factors, of 595 nm PDL in the treatment of PWSs in Chinese patients with skin type III to IV. Methods A total of 848 cases that were treated with PDL were enrolled and analyzed in this study. An independent dermatologist evaluated these lesions according to the before and after photographs. Results The response rate (RR) of all the 848 PWS patients was 69.9%, within which the cure rate was 6.3%. The patients aged ≤1 year had the highest RR (93.9%), whereas those treated after age 50 reacted the worst (RR =25%). We analyzed the anatomical distribution of the lesion and found that the temporal region had the highest lesion clearance (RR =75.3%), while the extremities had the lowest clearance (RR =44.5%). Compared with the patients whose lesion size was larger than 80 cm2, the patients with small lesion size, of 0–20 cm2, had better clinical effect (RR =73.8% vs 53.2%). The reactions of the patients with hyperplastic lesion were worse than those with red patches (RR =36.4% vs 71.7%). As well, increasing treatment numbers could achieve higher clearance rates (P=0.005). Conclusion The PDL had a relatively high RR but a low clearance rate in Chinese patients with PWS, although the earlier the intervention, the better was the efficacy. The response of PDL was, not only related to the anatomical area, but also, to the lesion size, type of lesion (ie, the presence of existing hyperplastic lesions), and the number of treatment, all of which are essential for the evaluation of therapeutic effect and acquisition of patients consent before treatment. PMID:25548515

Eliciting societal preferences of reimbursement decision criteria for anti cancer drugs in South Korea.

PubMed

Kwon, Sun-Hong; Park, Sun-Kyeong; Byun, Ji-Hye; Lee, Eui-Kyung

2017-08-01

In order to look beyond the cost-effectiveness analysis, this study used a multi-criteria decision analysis (MCDA), which reflects societal values with regard to reimbursement decisions. This study aims to elicit societal preferences of the reimbursement decision criteria for anti cancer drugs from public and healthcare professionals. Eight criteria were defined based on a literature review and focus group sessions: disease severity, disease population size, pediatrics targets, unmet needs, innovation, clinical benefits, cost-effectiveness, and budget impacts. Using quota sampling and purposive sampling, 300 participants from the Korean public and 30 healthcare professionals were selected for the survey. Preferences were elicited using an analytic hierarchy process. Both groups rated clinical benefits the highest, followed by cost-effectiveness and disease severity, but differed with regard to disease population size and unmet needs. Innovation was the least preferred criteria. Clinical benefits and other social values should be reflected appropriately with cost-effectiveness in healthcare coverage. MCDA can be used to assess decision priorities for complicated health policy decisions, including reimbursement decisions. It is a promising method for making logical and transparent drug reimbursement decisions that consider a broad range of factors, which are perceived as important by relevant stakeholders.

Effects of Mo, Cr, and V Additions on Tensile and Charpy Impact Properties of API X80 Pipeline Steels

NASA Astrophysics Data System (ADS)

Han, Seung Youb; Shin, Sang Yong; Seo, Chang-Hyo; Lee, Hakcheol; Bae, Jin-Ho; Kim, Kisoo; Lee, Sunghak; Kim, Nack J.

2009-08-01

In this study, four API X80 pipeline steels were fabricated by varying Mo, Cr, and V additions, and their microstructures and crystallographic orientations were analyzed to investigate the effects of their alloying compositions on tensile properties and Charpy impact properties. Because additions of Mo and V promoted the formation of fine acicular ferrite (AF) and granular bainite (GB) while prohibiting the formation of coarse GB, they increased the strength and upper-shelf energy (USE) and decreased the energy transition temperature (ETT). The addition of Cr promoted the formation of coarse GB and hard secondary phases, thereby leading to an increased effective grain size, ETT, and strength, and a decreased USE. The addition of V resulted in a higher strength, a higher USE, a smaller effective grain size, and a lower ETT, because it promoted the formation of fine and homogeneous of AF and GB. The steel that contains 0.3 wt pct Mo and 0.06 wt pct V without Cr had the highest USE and the lowest ETT, because its microstructure was composed of fine AF and GB while its maintained excellent tensile properties.

Interactive Video Gaming compared to Health Education in Older Adults with MCI: A Feasibility Study

PubMed Central

Hughes, Tiffany F.; Flatt, Jason D.; Fu, Bo; Butters, Meryl A.; Chang, Chung-Chou H.; Ganguli, Mary

2014-01-01

Objective We evaluated the feasibility of a trial of Wii interactive video gaming, and its potential efficacy at improving cognitive functioning compared to health education, in a community sample of older adults with neuropsychologically defined mild cognitive impairment (MCI). Methods Twenty older adults were equally randomized to either group-based interactive video gaming or health education for 90 minutes each week for 24 weeks. Although the primary outcomes were related to study feasibility, we also explored the effect of the intervention on neuropsychological performance and other secondary outcomes. Results All 20 participants completed the intervention, and 18 attended at least 80% of the sessions. The majority (80%) of participants were “very much” satisfied with the intervention. Bowling was enjoyed by the most participants, and was also the rated highest among the games for mental, social and physical stimulation. We observed medium effect sizes for cognitive and physical functioning in favor of the interactive video gaming condition, but these effects were not statistically significant in this small sample. Conclusion Interactive video gaming is feasible for older adults with MCI and medium effects sizes in favor of the Wii group warrant a larger efficacy trial. PMID:24452845

Factors Affecting Aerosol Radiative Forcing

NASA Astrophysics Data System (ADS)

Wang, Jingxu; Lin, Jintai; Ni, Ruijing

2016-04-01

Rapid industrial and economic growth has meant a large amount of aerosols in the atmosphere with strong radiative forcing (RF) upon the climate system. Over parts of the globe, the negative forcing of aerosols has overcompensated for the positive forcing of greenhouse gases. Aerosol RF is determined by emissions and various chemical-transport-radiative processes in the atmosphere, a multi-factor problem whose individual contributors have not been well quantified. In this study, we analyze the major factors affecting RF of secondary inorganic aerosols (SIOAs, including sulfate, nitrate and ammonium), primary organic aerosol (POA), and black carbon (BC). We analyze the RF of aerosols produced by 11 major regions across the globe, including but not limited to East Asia, Southeast Asia, South Asia, North America, and Western Europe. Factors analyzed include population size, per capita gross domestic production (GDP), emission intensity (i.e., emissions per unit GDP), chemical efficiency (i.e., mass per unit emissions) and radiative efficiency (i.e., RF per unit mass). We find that among the 11 regions, East Asia produces the largest emissions and aerosol RF, due to relatively high emission intensity and a tremendous population size. South Asia produce the second largest RF of SIOA and BC and the highest RF of POA, in part due to its highest chemical efficiency among all regions. Although Southeast Asia also has large emissions, its aerosol RF is alleviated by its lowest chemical efficiency. The chemical efficiency and radiative efficiency of BC produced by the Middle East-North Africa are the highest across the regions, whereas its RF is lowered by a small per capita GDP. Both North America and Western Europe have low emission intensity, compensating for the effects on RF of large population sizes and per capita GDP. There has been a momentum to transfer industries to Southeast Asia and South Asia, and such transition is expected to continue in the coming years. The resulting relocation of emissions would meant drastic changes in both the spatial distribution and the magnitude of RF, with consequences on regional and global climate forcing. Our findings are relevant to global aerosol control and climate mitigation.

Factors Affecting Aerosol Radiative Forcing

NASA Astrophysics Data System (ADS)

Wang, J.; Lin, J.; Ni, R.

2016-12-01

Rapid industrial and economic growth has meant large amount of aerosols in the atmosphere with strong radiative forcing (RF) upon the climate system. Over parts of the globe, the negative forcing of aerosols has overcompensated for the positive forcing of greenhouse gases. Aerosol RF is determined by emissions and various chemical-transport-radiative processes in the atmosphere, a multi-factor problem whose individual contributors have not been well quantified. In this study, we analyze the major factors affecting RF of secondary inorganic aerosols (SIOAs, including sulfate, nitrate and ammonium), primary organic aerosol (POA), and black carbon (BC). We analyze the RFof aerosols produced by 11 major regions across the globe, including but not limited to East Asia, Southeast Asia, South Asia, North America, and Western Europe. Factors analyzed include population size, per capita gross domestic production (GDP), emission intensity (i.e., emissionsper unit GDP), chemical efficiency (i.e., mass per unit emissions) and radiative efficiency (i.e., RF per unit mass). We find that among the 11 regions, East Asia produces the largest emissions and aerosol RF, due to relatively high emission intensity and a tremendous population size.South Asia produce the second largest RF of SIOA and BC and the highest RF of POA, in part due to its highest chemical efficiency among all regions. Although Southeast Asia also has large emissions,its aerosol RF is alleviated by its lowest chemical efficiency.The chemical efficiency and radiative efficiency of BC produced by the Middle East-North Africa are the highest across the regions, whereas its RF is loweredbyasmall per capita GDP.Both North America and Western Europe have low emission intensity, compensating for the effects on RF of large population sizes and per capita GDP. There has been a momentum to transfer industries to Southeast Asia and South Asia, and such transition is expected to continue in the coming years. The resulting relocation of emissions would meant drastic changes in both the spatial distribution and the magnitude of RF, with consequences on regional and global climate forcing. Our findings are relevant to global aerosol control and climate mitigation.

SU-G-IeP2-05: Effect of Localizer Type and Patient Off-Centering On CT Radiation Dose with Use of Automatic Tube Current Modulation

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

Ruan, C; Sodickson, A; Hamberg, L

2016-06-15

Purpose: Apparent patient size in CT localizers varies with localizer type and patient positioning, resulting in variation in effective mAs as guided by Tube Current Modulation (TCM). Our aim was to investigate the effects of vertical off-centering on CTDI-vol when using different localizer types and TCM strengths. Methods: A CTDI body phantom was scanned using an abdominal protocol with three TCM strengths (Siemens Definition AS40, CAREDose4D; very weak, average, very strong). Data was acquired at 11 table height positions; with phantom center at isocenter and at 10 other positions between 142mm below and 53mm above. At each position, scans weremore » acquired using 5 different localizer types: PA, AP, Lateral, PA+Lateral, and Lateral+PA. CTDI-vol was recorded for the 165 combinations of table height, localizer type, and TCM strength, and magnification factors measured from localizer images. Results: Magnification factors from AP and PA localizers ranged from 0.79–1.11 and 1.35–0.91, respectively from lowest to highest positions (highest with phantom located closest to X-ray tube), with a smaller impact when using Lateral, PA+Lateral, Lateral+PA localizer types, all of which behaved similarly. For an average TCM strength and PA localizer, CTDI-vol ranged from 75% higher to 12% lower than the isocenter value for the lowest to highest table positions, respectively. For table positions ranging from lowest to highest, CTDI-vol ranged from −23% to 17% for AP, from −8% to 0.3% for lateral and from −7% to 1% for a combination of PA and Lateral in either order. Similar behavior was found for different TCM strengths, but effects were more pronounced for very strong compared with very weak modulation strengths. Conclusion: Patient off-centering substantially impacts radiation dose, which depends on the amount of vertical offcentering and type of the localizer used. The combination of PA and Lateral localizers is most robust against effects of patient off-centering.« less

Post-breeding bird responses to canopy tree retention, stand size, and edge in regenerating Appalachian hardwood stands

USGS Publications Warehouse

McDermott, Molly E.; Wood, Petra B.

2011-01-01

Avian use of even-aged timber harvests is likely affected by stand attributes such as size, amount of edge, and retained basal area, all characteristics that can easily be manipulated in timber harvesting plans. However, few studies have examined their effects during the post-breeding period. We studied the impacts of clearcut, low-leave two-age, and high-leave two-age harvesting on post-breeding birds using transect sampling and mist-netting in north-central West Virginia. In our approach, we studied the effects of these harvest types as well as stand size and edge on species characteristic of both early-successional and mature forest habitats. In 2005–2006, 13 stands ranging from 4 to 10 years post-harvest and 4–21 ha in size were sampled from late June through mid-August. Capture rates and relative abundance were similar among treatments for generalist birds. Early-successional birds had the lowest capture rates and fewer species (∼30% lower), and late-successional birds reached their highest abundance and species totals (double the other treatments) in high-leave two-age stands. Area sensitivity was evident for all breeding habitat groups. Both generalist and late-successional bird captures were negatively related to stand size, but these groups showed no clear edge effects. Mean relative abundance decreased to nearly zero for the latter group in the largest stands. In contrast, early-successional species tended to use stand interiors more often and responded positively to stand size. Capture rates for this group tripled as stand size increased from 4 to 21 ha. Few birds in the forest periphery responded to harvest edge types despite within-stand edge effects evident for several species. To create suitable habitat for early-successional birds, large, non-linear openings with a low retained basal area are ideal, while smaller harvests and increased residual tree retention would provide habitat for more late-successional birds post-breeding. Although our study has identified habitat use patterns for different species in timber harvests, understanding habitat-specific bird survival is needed to help determine the quality of silvicultural harvests for post-breeding birds.

Estimating the Effects of Parental Divorce and Death With Fixed Effects Models

PubMed Central

Amato, Paul R.; Anthony, Christopher J.

2014-01-01

The authors used child fixed effects models to estimate the effects of parental divorce and death on a variety of outcomes using 2 large national data sets: (a) the Early Childhood Longitudinal Study, Kindergarten Cohort (kindergarten through the 5th grade) and (b) the National Educational Longitudinal Study (8th grade to the senior year of high school). In both data sets, divorce and death were associated with multiple negative outcomes among children. Although evidence for a causal effect of divorce on children was reasonably strong, effect sizes were small in magnitude. A second analysis revealed a substantial degree of variability in children’s outcomes following parental divorce, with some children declining, others improving, and most not changing at all. The estimated effects of divorce appeared to be strongest among children with the highest propensity to experience parental divorce. PMID:24659827

Concentrations and size distribution of inhalable and respirable dust among sugar industry workers: a pilot study in Khon Kaen, Thailand.

PubMed

Sakunkoo, Pornpun; Chaiear, Naesinee; Chaikittiporn, Chalermchai; Sadhra, Steven

2011-11-01

There has been very limited information regarding bagasse exposure among workers in sugar industries as well as on health outcomes. The authors determined the occupational exposure of sugar industry workers in Khon Kaen to airborne bagasse dust. The size of the bagasse dust ranged from 0.08 to 9 µm with the highest size concentration of 2.1 to 4.7 µm. The most common size had a geometric mean diameter of 5.2 µm, with a mass concentration of 6.89 mg/m(3)/log µm. The highest mean values of inhalable and respirable dust were found to be 9.29 mg/m(3) from February to April in bagasse storage, 5.12 mg/m(3) from May to September, and 4.12 mg/m(3) from October to January. Inhalable dust concentrations were 0.33, 0.47, and 0.41 mg/m(3), respectively. Workers are likely to be exposed to high concentrations of bagasse dust and are at risk of respiratory diseases. Preventive measures, both in the form of engineering designs and personal protective devices, should be implemented.

Emission characteristics and chemical components of size-segregated particulate matter in iron and steel industry

NASA Astrophysics Data System (ADS)

Jia, Jia; Cheng, Shuiyuan; Yao, Sen; Xu, Tiebing; Zhang, Tingting; Ma, Yuetao; Wang, Hongliang; Duan, Wenjiao

2018-06-01

As one of the highest energy consumption and pollution industries, the iron and steel industry is regarded as a most important source of particulate matter emission. In this study, chemical components of size-segregated particulate matters (PM) emitted from different manufacturing units in iron and steel industry were sampled by a comprehensive sampling system. Results showed that the average particle mass concentration was highest in sintering process, followed by puddling, steelmaking and then rolling processes. PM samples were divided into eight size fractions for testing the chemical components, SO42- and NH4+ distributed more into fine particles while most of the Ca2+ was concentrated in coarse particles, the size distribution of mineral elements depended on the raw materials applied. Moreover, local database with PM chemical source profiles of iron and steel industry were built and applied in CMAQ modeling for simulating SO42- and NO3- concentration, results showed that the accuracy of model simulation improved with local chemical source profiles compared to the SPECIATE database. The results gained from this study are expected to be helpful to understand the components of PM in iron and steel industry and contribute to the source apportionment researches.

Micromagnetic finite element simulation of nanocrystalline α-Fe/Nd2Fe14B/Fe3B magnets

NASA Astrophysics Data System (ADS)

Saiden, N. M.; Schrefl, T.; Davies, H. A.; Hrkac, G.

2014-09-01

Nanocomposite Nd2Fe14B permanent magnets with Fe3B and α-Fe as the soft phase have been simulated using micromagnetic modelling. This paper reviews extensively the results from the simulation point of view. The magnetization configuration along the hysteresis loop is discussed in details. It was clear that the grain size and phase distribution play important roles in determining the magnetic properties. By changing the size of the grain and the volume fraction of the hard and soft phase, the magnetic properties change and the relationship between microstructure and properties is investigated. The remanence, Jr increases with decreasing of grain size, but oppositely for coercivity, Hc. The highest Jr, 1.46 T was obtained with a grain size 10 nm, and volume fraction of α-Fe, 40%. Whereas, the highest Hc with combination Nd2Fe14B 80% and 20% Fe3B, 947 kA/m. On the other hand, if Nd2Fe14B alone, the Hc able to reach up to 1000 kA/m. From this study, micromagnetic modelling contributes to a better understanding how microstructure and phase distribution influences the magnetic properties.

Macrobenthos and megabenthos responses to long-term, large-scale hypoxia on the Louisiana continental shelf.

PubMed

Briggs, Kevin B; Craig, J Kevin; Shivarudrappa, S; Richards, T M

2017-02-01

The macrobenthos and megabenthos responses to long-term, recurring hypoxia on the Louisiana continental shelf were compared at four locations with different historical (2000-2010) episodes of annual exposure to bottom-water hypoxia. Measurements of abundance, biomass, species diversity, and community composition of the two size classes of benthos suggested that the macrobenthic response is driven chiefly by tolerance to hypoxia, whereas the megabenthic response was affected by the ability to migrate and the availability/unavailability of macrobenthos prey at the sediment surface. The site exposed to the historically lowest average bottom-water dissolved oxygen (BWDO) concentration exhibited the lowest species diversity for macrobenthos and the highest species diversity for megabenthos, exemplifying the differential effects of hypoxia on different size classes. The high diversity and smaller average size of the megabenthos at the lowest DO site was due to high abundance of invertebrates and a preponderance of small, less vagile fishes that appeared to remain in the area after larger dominant sciaenids had presumably emigrated. The average size and the depth of habitation in the sediment of macrobenthos prey may have also influenced the abundance and biomass of megabenthos foragers. Published by Elsevier Ltd.

Exposure to ultrafine particles in hospitality venues with partial smoking bans.

PubMed

Neuberger, Manfred; Moshammer, Hanns; Schietz, Armin

2013-01-01

Fine particles in hospitality venues with insufficient smoking bans indicate health risks from passive smoking. In a random sample of Viennese inns (restaurants, cafes, bars, pubs and discotheques) effects of partial smoking bans on indoor air quality were examined by measurement of count, size and chargeable surface of ultrafine particles (UFPs) sized 10-300 nm, simultaneously with mass of particles sized 300-2500 nm (PM2.5). Air samples were taken in 134 rooms unannounced during busy hours and analyzed by a diffusion size classifier and an optical particle counter. Highest number concentrations of particles were found in smoking venues and smoking rooms (median 66,011 pt/cm(3)). Even non-smoking rooms adjacent to smoking rooms were highly contaminated (median 25,973 pt/cm(3)), compared with non-smoking venues (median 7408 pt/cm(3)). The particle number concentration was significantly correlated with the fine particle mass (P<0.001). We conclude that the existing tobacco law in Austria is ineffective to protect customers in non-smoking rooms of hospitality premises. Health protection of non-smoking guests and employees from risky UFP concentration is insufficient, even in rooms labeled "non-smoking". Partial smoking bans with separation of smoking rooms failed.

Seasonal variability in size-segregated airborne bacterial particles and their characterization at different source-sites.

PubMed

Agarwal, Smita

2017-05-01

Size-segregated aerosol samplings were carried out near the potential sources of airborne biological particles i.e. at a landfill site, an agricultural field and a road side restaurant-cluster site in winter, spring and summer seasons during 2013-2015 in New Delhi. The culturable airborne bacterial (CAB) concentrations showed significant seasonal variation from higher to moderate in spring and winter seasons and lowest during summer. Highest CAB concentrations were observed at the Okhla landfill site followed by restaurant-cluster area and agriculture site. The CAB particles showed bimodal size distribution, abundant in the size ranges of 1.1-2.1, 2.1-3.3 and 4.7-5.8 μm. However, substantial concentrations were also observed in the size bins of 0.43-0.65 and <0.43 μm, which are important for cloud condensation nuclei (CCN) activity of aerosols in addition to their adverse health effects. In spring, bacterial particles were also maximized in size ranges between 5.8 and >9.0 μm. Fine mode proportions of CAB were found to be higher in winter than other two seasons. Bacterial identification was done by 16s rDNA sequencing, and most abundant identified strains were Bacillus cereus (16%), Bacillus licheniformis (11%), Bacillus thuringiensis (9%), Micrococcus sp. (7%) and Acinetobacter sp. (9%).

Dislocation, crystallite size distribution and lattice strain of magnesium oxide nanoparticles

NASA Astrophysics Data System (ADS)

Sutapa, I. W.; Wahid Wahab, Abdul; Taba, P.; Nafie, N. L.

2018-03-01

The oxide of magnesium nanoparticles synthesized using sol-gel method and analysis of the structural properties was conducted. The functional groups of nanoparticles has been analysed by Fourier Transform Infrared Spectroscopy (FT-IR). Dislocations, average size of crystal, strain, stress, the energy density of crystal, crystallite size distribution and morphologies of the crystals were determined based on X-ray diffraction profile analysis. The morphological of the crystal was analysed based on the image resulted from SEM analysis. The crystallite size distribution was calculated with the contention that the particle size has a normal logarithmic form. The most orientations of crystal were determined based on the textural crystal from diffraction data of X-ray diffraction profile analysis. FT-IR results showed the stretching vibration mode of the Mg-O-Mg in the range of 400.11-525 cm-1 as a broad band. The average size crystal of nanoparticles resulted is 9.21 mm with dislocation value of crystal is 0.012 nm-2. The strains, stress, the energy density of crystal are 1.5 x 10-4 37.31 MPa; 0.72 MPa respectively. The highest texture coefficient value of the crystal is 0.98. This result is supported by morphological analysis using SEM which shows most of the regular cubic-shaped crystals. The synthesis method is suitable for simple and cost-effective synthesis model of MgO nanoparticles.

Coupled CFD-PBE Predictions of Renal Stone Size Distributions in the Nephron in Microgravity

NASA Technical Reports Server (NTRS)

Kassemi, Mohammad; Griffin, Elise; Thompson, David

2016-01-01

In this paper, a deterministic model is developed to assess the risk of critical renal stone formation for astronauts during space travel. A Population Balance Equation (PBE) model is used to compute the size distribution of a population of nucleating, growing and agglomerating renal calculi as they are transported through different sections of the nephron. The PBE model is coupled to a Computational Fluid Dynamics (CFD) model that solves for steady state flow of urine and transport of renal calculi along with the concentrations of ionic species, calcium and oxalate, in the nephron using an Eulerian two-phase mathematical framework. Parametric simulation are performed to study stone size enhancement and steady state volume fraction distributions in the four main sections of the nephron under weightlessness conditions. Contribution of agglomeration to the stone size distribution and effect of wall friction on the stone volume fraction distributions are carefully examined. Case studies using measured astronaut urinary calcium and oxalate concentrations in microgravity as input indicate that under nominal conditions the largest stone sizes developed in Space will be still considerably below the critical range for problematic stone development. However, results also indicate that the highest stone volume fraction occurs next to the tubule and duct walls. This suggests that there is an increased potential for wall adhesion with the possibility of evolution towards critical stone sizes.

Effects of Cr-N-ZrO 2 seed layer formed on glass substrates for longitudinal recording media

NASA Astrophysics Data System (ADS)

Suzuki, Hiroyuki; Djayaprawira, David D.; Takahashi, Yoshio; Ishikawa, Akira; Ono, Toshinori; Yahisa, Yotsuo

1999-03-01

Effects of Cr-N-ZrO 2 seed layer deposited on glass substrates before the deposition of C/Co-Cr-Pt/Cr-Ti layers for longitudinal recording media have been investigated. The product of v and Is, the activation volume and the saturation magnetization per unit volume, media noise Nd and S0/ Nd, which is the half value of peak-to-peak output voltage of an isolated pulse over Nd at 11.8 kFC/mm, are evaluated. We find that vIs is decreased by adding N and ZrO 2 to Cr seed layer. Nd is reduced as vIs decreases by adding nitrogen to the Cr seed layer. This is mainly due to the decreased grain sizes of both Cr-Ti underlayer and Co-Cr-Pt magnetic layer. The Nd is further reduced by the addition of ZrO 2 to the Cr-N seed layer. Highest S0/ Nd is achieved for the media with Cr-N-ZrO 2 seed layer. On the other hand, the media with Cr-ZrO 2 seed layer deposited without nitrogen show the higher Nd. Therefore the decrease of the grain size by addition of nitrogen into Ar is essential to reduce Nd, and the ZrO 2 addition to the Cr-N seed layer seems to enhance the effect of grain size reduction by nitrogen addition.

Performances of Different Fragment Sizes for Reduced Representation Bisulfite Sequencing in Pigs.

PubMed

Yuan, Xiao-Long; Zhang, Zhe; Pan, Rong-Yang; Gao, Ning; Deng, Xi; Li, Bin; Zhang, Hao; Sangild, Per Torp; Li, Jia-Qi

2017-01-01

Reduced representation bisulfite sequencing (RRBS) has been widely used to profile genome-scale DNA methylation in mammalian genomes. However, the applications and technical performances of RRBS with different fragment sizes have not been systematically reported in pigs, which serve as one of the important biomedical models for humans. The aims of this study were to evaluate capacities of RRBS libraries with different fragment sizes to characterize the porcine genome. We found that the Msp I-digested segments between 40 and 220 bp harbored a high distribution peak at 74 bp, which were highly overlapped with the repetitive elements and might reduce the unique mapping alignment. The RRBS library of 110-220 bp fragment size had the highest unique mapping alignment and the lowest multiple alignment. The cost-effectiveness of the 40-110 bp, 110-220 bp and 40-220 bp fragment sizes might decrease when the dataset size was more than 70, 50 and 110 million reads for these three fragment sizes, respectively. Given a 50-million dataset size, the average sequencing depth of the detected CpG sites in the 110-220 bp fragment size appeared to be deeper than in the 40-110 bp and 40-220 bp fragment sizes, and these detected CpG sties differently located in gene- and CpG island-related regions. In this study, our results demonstrated that selections of fragment sizes could affect the numbers and sequencing depth of detected CpG sites as well as the cost-efficiency. No single solution of RRBS is optimal in all circumstances for investigating genome-scale DNA methylation. This work provides the useful knowledge on designing and executing RRBS for investigating the genome-wide DNA methylation in tissues from pigs.

Revisiting the impact of mobile phone screen size on user comprehension of health information.

PubMed

Alghamdi, Ebtisam; Yunus, Faisel; Househ, Mowafa

2014-01-01

Abstract goes here. This is completion of the research and update of the previous work that was published in 2013[1]. The paper describes our recent experimental study of the impact of mobile screen size on the user comprehension of health information and application structures. An experiment was conducted to measure the impact of screen size on user comprehension and retention. Participants were given the same simple scenario, which consisted of searching from different menus, navigating and reading some contents. They were timed and tracked for correctness. Also, a follow-up survey was given to each participant that consisted of a rating scale to assess usability features, comprehension and retention abilities of the participants based on different mobile screen sizes. Results showed that there was a significant difference between mobile phone screen size and the time taken to read the contents, which was at its highest on small screens (p-value=0.02). Also, reading characters was hardest on a small screen (p-value=0.003). In addition, there was a significant difference between the three screen sizes regarding the organization of the application's information, showing that the smaller the screen size, the more organized the information. On the other hand, there was no significant impact of screen size on user comprehension, retention scores, number of errors or effective task completion but it was generally better if a large screen size was used. This study concludes that the screen size is not the main concern in comprehension of the contents or application structure. However, reading speed improves with the larger screen size and positively influences the task completion and understanding of the application elements.

Behavior of pentacene initial nucleation on various dielectrics and its effect on carrier transport in organic field-effect transistor.

PubMed

Qi, Qiong; Yu, Aifang; Wang, Liangmin; Jiang, Chao

2010-11-01

The influence of dielectric surface energy on the initial nucleation and the growth of pentacene films as well as the electrical properties of the pentacene-based field-effect transistors are investigated. We have examined a range of organic and inorganic dielectrics with different surface energies, such as polycarbonate/SiO2, polystyrene/SiO2, and PMMA/SiO2 bi-layered dielectrics and also the bare SiO2 dielectric. Atomic force microscopy measurements of sub-monolayer and thick pentacene films indicated that the growth of pentacene film was in Stranski-Kranstanow growth mode on all the dielectrics. However, the initial nucleation density and the size of the first-layered pentacene islands deposited on different dielectrics are drastically influenced by the dielectric surface energy. With the increasing of the surface energy, the nucleation density increased and thus the average size of pentacene islands for the first mono-layer deposition decreased. The performance of fabricated pentacene-based thin film transistors was found to be highly related to nucleation density and the island size of deposited Pentacene film, and it had no relationship to the final particle size of the thick pentacene film. The field effect mobility of the thin film transistor could be achieved as high as 1.38 cm2Ns with on/off ratio over 3 x 10(7) on the PS/SiO2 where the lowest surface energy existed among all the dielectrics. For comparison, the values of mobility and on/off ratio were 0.42 cm2Ns and 1 x 10(6) for thin film transistor deposited directly on bare SiO2 having the highest surface energy.

Comparison of the frictional characteristics of aesthetic orthodontic brackets measured using a modified in vitro technique

PubMed Central

Arici, Nursel

2015-01-01

Objective The coefficients of friction (COFs) of aesthetic ceramic and stainless steel brackets used in conjunction with stainless steel archwires were investigated using a modified linear tribometer and special computer software, and the effects of the bracket slot size (0.018 inches [in] or 0.022 in) and materials (ceramic or metal) on the COF were determined. Methods Four types of ceramic (one with a stainless steel slot) and one conventional stainless steel bracket were tested with two types of archwire sizes: a 0.017 × 0.025-in wire in the 0.018-in slots and a 0.019 × 0.025-in wire in the 0.022-in slot brackets. For pairwise comparisons between the 0.018-in and 0.022-in slot sizes in the same bracket, an independent sample t-test was used. One-way and two-way analysis of variance (ANOVA) and Tukey's post-hoc test at the 95% confidence level (α = 0.05) were also used for statistical analyses. Results There were significant differences between the 0.022-in and 0.018-in slot sizes for the same brand of bracket. ANOVA also showed that both slot size and bracket slot material had significant effects on COF values (p < 0.001). The ceramic bracket with a 0.022-in stainless steel slot showed the lowest mean COF (µ = 0.18), followed by the conventional stainless steel bracket with a 0.022-in slot (µ = 0.21). The monocrystalline alumina ceramic bracket with a 0.018-in slot had the highest COF (µ = 0.85). Conclusions Brackets with stainless steel slots exhibit lower COFs than ceramic slot brackets. All brackets show lower COFs as the slot size increases. PMID:25667915

Diet of the Antillean manatee (Trichechus manatus manatus) in Belize, Central America

USGS Publications Warehouse

Allen, Aarin Conrad; Beck, Cathy A.; Bonde, Robert K.; Powell, James A.; Gomez, Nicole Auil

2017-01-01

Belize contains important habitat for Antillean manatees (Trichechus manatus manatus) and provides refuge for the highest known population density of this subspecies. As these animals face impending threats, knowledge of their dietary habits can be used to interpret resource utilization. The contents of 13 mouth, 6 digestive tract (stomach, duodenum and colon), and 124 fecal samples were microscopically examined using a modified point technique detection protocol to identify key plant species consumed by manatees at two important aggregation sites in Belize: Southern Lagoon and the Drowned Cayes. Overall, 15 different items were identified in samples from manatees in Belize. Five species of seagrasses (Halodule wrightii, Thalassia testudinum, Ruppia maritima, Syringodium filiforme, and Halophila sp.) made up the highest percentage of items. The red mangrove (Rhizophora mangle), was also identified as an important food item. Algae (Ulva sp., Chara sp., Lyngbya sp.) and invertebrates (sponges and diatoms) were also consumed. Variation in the percentage of seagrasses, other vascular plants, and algae consumption was analyzed as a 4-factor analysis of variance (ANOVA) with main effects and interactions for locality, sex, size classification, and season. While sex and season did not influence diet composition, differences for locality and size classification were observed. These results suggest that analysis of diet composition of Antillean manatees may help to determine critical habitat and use of associated food resources which, in turn can be used to aid conservation efforts in Belize.

Comparative assessment of synthetic strategies toward active platinum-rhodium-tin electrocatalysts for efficient ethanol electro-oxidation

NASA Astrophysics Data System (ADS)

Erini, Nina; Krause, Paul; Gliech, Manuel; Yang, Ruizhi; Huang, Yunhui; Strasser, Peter

2015-10-01

The present work explores the effect of autoclave-based autogenous-pressure vs. ambient pressure conditions on the synthesis and properties of carbon-supported Pt-Rh-Sn nanoparticle electrocatalysts. The Pt-Rh-Sn nanoparticles were characterized by X-ray spectroscopy, electron microscopy and mass spectroscopy and deployed as catalysts for the electrocatalytic ethanol oxidation reaction. Pt-Rh-Sn catalysts precipitated with carbon already present showed narrow particle size distribution around 7 nm, while catalysts supported on carbon after particle formation showed broader size distribution ranging from 8 to 16 nm, similar metal loadings between 40 and 48 wt.% and similar atomic ratios of Pt:Rh:Sn of 30:10:60. The highest ethanol oxidation activity at low overpotentials associated with exceptionally early ethanol oxidation onset potential was observed for ambient-pressure catalysts with the active ternary alloy phase formed in presence of the carbon supports. In contrast, catalysts prepared under ambient pressure in a two-step approach, involving alloy particle formation followed by particle separation and subsequent deposition on the carbon support, yielded the highest overall mass activities. Based on the observed synthesis-activity correlations, a comparative assessment is provided of the synthetic techniques at high vs. low pressures, and in presence and absence of carbon support. Plausible hypotheses in terms of particle dispersion and interparticle distance accounting for these observed differences are discussed.

Chitosan-based hydrogel tissue scaffolds made by 3D plotting promotes osteoblast proliferation and mineralization.

PubMed

Liu, I-Hsin; Chang, Shih-Hsin; Lin, Hsin-Yi

2015-05-13

A 3D plotting system was used to make chitosan-based tissue scaffolds with interconnected pores using pure chitosan (C) and chitosan cross-linked with pectin (CP) and genipin (CG). A freeze-dried chitosan scaffold (CF/D) was made to compare with C, to observe the effects of structural differences. The fiber size, pore size, porosity, compression strength, swelling ratio, drug release efficacy, and cumulative weight loss of the scaffolds were measured. Osteoblasts were cultured on the scaffolds and their proliferation, type I collagen production, alkaline phosphatase activity, calcium deposition, and morphology were observed. C had a lower swelling ratio, degradation, porosity and drug release efficacy and a higher compressional stiffness and cell proliferation compared to CF/D (p < 0.05). Of the 3D-plotted samples, cells on CP exhibited the highest degree of mineralization after 21 d (p < 0.05). CP also had the highest swelling ratio and fastest drug release, followed by C and CG (p < 0.05). Both CP and CG were stiffer and degraded more slowly in saline solution than C (p < 0.05). In summary, 3D-plotted scaffolds were stronger, less likely to degrade and better promoted osteoblast cell proliferation in vitro compared to the freeze-dried scaffolds. C, CP and CG were structurally similar, and the different crosslinking caused significant changes in their physical and biological performances.

Effect of NaCl addition during diafiltration on the solubility, hydrophobicity, and disulfide bonds of 80% milk protein concentrate powder.

PubMed

Mao, X Y; Tong, P S; Gualco, S; Vink, S

2012-07-01

We investigated the surface hydrophobicity index based on different fluorescence probes [1-anilinonaphthalene-8-sulfonic acid (ANS) and 6-propionyl-2-(N,N-dimethylamino)-naphthalene (PRODAN)], free sulfhydryl and disulfide bond contents, and particle size of 80% milk protein concentrate (MPC80) powders prepared by adding various amounts of NaCl (0, 50, 100, and 150 mM) during the diafiltration process. The solubility of MPC80 powder was not strictly related to surface hydrophobicity. The MPC80 powder obtained by addition of 150 mM NaCl during diafiltration had the highest solubility but also the highest ANS-based surface hydrophobicity, the lowest PRODAN-based surface hydrophobicity, and the least aggregate formation. Intermolecular disulfide bonds caused by sulfhydryl-disulfide interchange reactions and hydrophobic interactions may be responsible for the lower solubility of the control MPC80 powder. The enhanced solubility of MPC80 powder with addition of NaCl during diafiltration may result from the modified surface hydrophobicity, the reduced intermolecular disulfide bonds, and the associated decrease in mean particle size. Addition of NaCl during the diafiltration process can modify the strength of hydrophobic interactions and sulfhydryl-disulfide interchange reactions and thereby affect protein aggregation and the solubility of MPC powders. Copyright © 2012 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

The role of beaded activated carbon's pore size distribution on heel formation during cyclic adsorption/desorption of organic vapors.

PubMed

Jahandar Lashaki, Masoud; Atkinson, John D; Hashisho, Zaher; Phillips, John H; Anderson, James E; Nichols, Mark

2016-09-05

The effect of activated carbon's pore size distribution (PSD) on heel formation during adsorption of organic vapors was investigated. Five commercially available beaded activated carbons (BAC) with varying PSDs (30-88% microporous) were investigated. Virgin samples had similar elemental compositions but different PSDs, which allowed for isolating the contribution of carbon's microporosity to heel formation. Heel formation was linearly correlated (R(2)=0.91) with BAC micropore volume; heel for the BAC with the lowest micropore volume was 20% lower than the BAC with the highest micropore volume. Meanwhile, first cycle adsorption capacities and breakthrough times correlated linearly (R(2)=0.87 and 0.93, respectively) with BAC total pore volume. Micropore volume reduction for all BACs confirmed that heel accumulation takes place in the highest energy pores. Overall, these results show that a greater portion of adsorbed species are converted into heel on highly microporous adsorbents due to higher share of high energy adsorption sites in their structure. This differs from mesoporous adsorbents (low microporosity) in which large pores contribute to adsorption but not to heel formation, resulting in longer adsorbent lifetime. Thus, activated carbon with high adsorption capacity and high mesopore fraction is particularly desirable for organic vapor application involving extended adsorption/regeneration cycling. Copyright © 2016 Elsevier B.V. All rights reserved.

Effect of compositions in nanostructured lipid carriers (NLC) on skin hydration and occlusion

PubMed Central

Loo, CH; Basri, M; Ismail, R; Lau, HLN; Tejo, BA; Kanthimathi, MS; Hassan, HA; Choo, YM

2013-01-01

Purpose To study the effects of varying lipid concentrations, lipid and oil ratio, and the addition of propylene glycol and lecithin on the long-term physical stability of nanostructured lipid nanocarriers (NLC), skin hydration, and transepidermal water loss. Methods The various NLC formulations (A1–A5) were prepared and their particle size, zeta potential, viscosity, and stability were analyzed. The formulations were applied on the forearms of the 20 female volunteers (one forearm of each volunteer was left untreated as a control). The subjects stayed for 30 minutes in a conditioned room with their forearms uncovered to let the skin adapt to the temperature (22°C ± 2°C) and humidity (50% ± 2%) of the room. Skin hydration and skin occlusion were recorded at day one (before treatment) and day seven (after treatment). Three measurements for skin hydration and skin occlusion were performed in each testing area. Results NLC formulations with the highest lipid concentration, highest solid lipid concentration, and additional propylene glycol (formulations A1, A2, and A5) showed higher physical stability than other formulations. The addition of propylene glycol into an NLC system helped to reduce the particle size of the NLC and enhanced its long-term physical stability. All the NLC formulations were found to significantly increase skin hydration compared to the untreated controls within 7 days. All NLC formulations exhibited occlusive properties as they reduced the transepidermal water loss within 7 days. This effect was more pronounced with the addition of propylene glycol or lecithin into an NLC formulation, whereby at least 60% reduction in transepidermal water loss was observed. Conclusion NLCs with high lipid content, solid lipid content, phospholipid, and lecithin are a highly effective cosmetic delivery system for cosmetic topical applications that are designed to boost skin hydration. PMID:23293516

Optimizing Training Population Size and Genotyping Strategy for Genomic Prediction Using Association Study Results and Pedigree Information. A Case of Study in Advanced Wheat Breeding Lines.

PubMed

Cericola, Fabio; Jahoor, Ahmed; Orabi, Jihad; Andersen, Jeppe R; Janss, Luc L; Jensen, Just

2017-01-01

Wheat breeding programs generate a large amount of variation which cannot be completely explored because of limited phenotyping throughput. Genomic prediction (GP) has been proposed as a new tool which provides breeding values estimations without the need of phenotyping all the material produced but only a subset of it named training population (TP). However, genotyping of all the accessions under analysis is needed and, therefore, optimizing TP dimension and genotyping strategy is pivotal to implement GP in commercial breeding schemes. Here, we explored the optimum TP size and we integrated pedigree records and genome wide association studies (GWAS) results to optimize the genotyping strategy. A total of 988 advanced wheat breeding lines were genotyped with the Illumina 15K SNPs wheat chip and phenotyped across several years and locations for yield, lodging, and starch content. Cross-validation using the largest possible TP size and all the SNPs available after editing (~11k), yielded predictive abilities (rGP) ranging between 0.5-0.6. In order to explore the Training population size, rGP were computed using progressively smaller TP. These exercises showed that TP of around 700 lines were enough to yield the highest observed rGP. Moreover, rGP were calculated by randomly reducing the SNPs number. This showed that around 1K markers were enough to reach the highest observed rGP. GWAS was used to identify markers associated with the traits analyzed. A GWAS-based selection of SNPs resulted in increased rGP when compared with random selection and few hundreds SNPs were sufficient to obtain the highest observed rGP. For each of these scenarios, advantages of adding the pedigree information were shown. Our results indicate that moderate TP sizes were enough to yield high rGP and that pedigree information and GWAS results can be used to greatly optimize the genotyping strategy.

Highly Efficient Catalytic Hydrogen Evolution from Ammonia Borane Using the Synergistic Effect of Crystallinity and Size of Noble-Metal-Free Nanoparticles Supported by Porous Metal-Organic Frameworks.

PubMed

Liu, Penglong; Gu, Xiaojun; Kang, Kai; Zhang, Hao; Cheng, Jia; Su, Haiquan

2017-03-29

A series of nonprecious metal nanoparticles (NPs) supported by metal-organic framework MIL-101 were synthesized using four methods and their catalytic performance on hydrogen evolution from ammonia borane (NH 3 BH 3 ) was studied. The results showed that the crystalline Co NPs with size of 4.5-8.5 and 14.5-24.5 nm had low activities featuring the total turnover frequency (TOF) values of 9.9 and 4.5 mol H2 mol cat -1 min -1 , respectively. In contrast, the amorphous Co NPs with size of 1.6-2.6 and 13.5-24.5 nm exhibited high activities featuring the total TOF values of 51.4 and 22.3 mol H2 mol cat -1 min -1 , respectively. The remarkably different activities could be ascribed to the different crystallinity and size of Co NPs in the catalysts. Moreover, the ultrasound-assisted in situ method was also successfully applied to bimetallic systems, and MIL-101-supported amorphous CuCo, FeCo and NiCo NPs had the catalytic activities with total TOF values of 51.7, 50.8, and 44.3 mol H2 mol cat -1 min -1 , respectively, which were the highest in the values of the reported non-noble metal Co-based catalysts. The present approach, namely, using the synergistic effect of crystallinity and size of metal NPs, may offer a new prospect for high-performance and low-cost nanocatalysts.

Reintroduction of the highly endangered mollusk Patella ferruginea Gmelin, 1791 in an MPA: A novel approach to achieve high survival rates

NASA Astrophysics Data System (ADS)

Zarrouk, Anis; Romdhane, Mohamed Salah; Espinosa, Free

2018-03-01

Patella ferruginea is the most endangered marine invertebrate of western Mediterranean rocky shores. After a study of one of its most important populations in the Zembra Archipelago National Park (Tunisia), a new protocol for the translocation of the species (size: 4-8 cm) was adopted. The first translocation was made in June 2014 in the same archipelago, where 94 specimens were moved from Zembretta to Zembra Island and marked (62 protected by cages, 20 with no cages and 60 as controls). The second translocation was performed in August 2014 (110 specimens) from Zembra to La Galite Island (185 km away). High mortality was registered during transport. The remaining individuals (39) were marked and placed in cages on the rocky shores of Galite Island, then monitored until November 2015. Growth and survival rates were measured in both translocated and control populations. The highest mortality rates were observed during the initial three days after translocation, especially for individuals with no cage protection. After a 697-day survey on Zembra Island, survival rates of 58%, 25% and 85% were observed for cage, no-cage and control populations, respectively. After a 457-day survey on La Galite Island, the survival rate was 18%. Limpets>6 cm in size had the highest survival rate among Zembra-translocated populations, whereas translocated limpets of 4-6 cm in size showed the highest survival rate in La Galite. The growth rates for both translocated populations were higher than the rate observed for controls. Our translocation experiment shows the importance of cage protection and initial limpet size for survival.

Design and Development of Repaglinide Microemulsion Gel for Transdermal Delivery.

PubMed

Shinde, Ujwala A; Modani, Sheela H; Singh, Kavita H

2018-01-01

Microemulsion formulation of repaglinide, a BCS class II hypoglycemic agent with limited oral bioavailability, was developed considering its solubility in various oils, surfactants, and cosurfactants. The pseudo-ternary phase diagrams for microemulsion regions were constructed by water titration method at K m 1:1 and characterized for optical birefringence, percentage transmittance, pH, refractive index, globule size, zeta potential, viscosity, drug content, and thermodynamic stability. To enhance the drug permeation and residence time, the optimized microemulsions having mean globule size of 36.15 ± 9.89 nm was gelled with xanthan gum. The developed microemulsion-based gel was characterized for globule size, zeta potential, pH, and drug content. All evaluation parameters upon gelling were found to be satisfactory. Ex vivo permeability study across rat skin demonstrated higher steady-state flux (P < 0.05) for microemulsion of repaglinide in comparison to the repaglinide microemulsion gel. At the end of 24 h, the cumulative drug permeation from microemulsion and microemulsion gel was found to be 229.19 ± 24.34 and 180.84 ± 17.40 μg/cm 2 , respectively. The microemulsion formulation showed 12.30-fold increase in flux as compared to drug suspension with highest enhancement ratio (E r ) of 12.36. Whereas microemulsion gel exhibited 10.97-fold increase in flux (with highest E r , 11.78) as compared to repaglinide (RPG) suspension. In vivo efficacy study was performed in normal Sprague-Dawley rats by using oral glucose tolerance test. Results of RPG transdermal microemulsion gel demonstrated remarkable advantage over orally administered RPG by reducing the glucose level in controlled manner. Hence, it could be a new, alternative dosage form for effective therapy of type 2 diabetes mellitus.

Linking particle number concentration (PNC), meteorology and traffic variables in a UK street canyon

NASA Astrophysics Data System (ADS)

Price, Heather D.; Arthur, Robert; BéruBé, Kelly A.; Jones, Tim P.

2014-10-01

Ambient particle number concentration (PNC) has been linked with adverse health outcomes such as asthma, reduced lung function and cardiovascular disease. To investigate the relationship between PNC, meteorology and traffic we measured size segregated respirable particles in a busy commuter street in Swansea, UK for ten months using a Dekati Electrical Low Pressure Impactor (ELPI). The ELPI segregates particles into 12 size fractions between 7 nm and 10 μm. The median PNC for the sampling period was 31,545 cm- 3. For the ultrafine particles (7-93 nm), the highest PNC was found in winter (46,615 cm- 3; 15 minute average) and the lowest for that size fraction in summer (29,696 cm- 3). For the particles below 93 nm there was a trimodal distribution to weekdays (particularly Monday to Wednesday), with PNC peaks at 09:00, 16:00 and 23:00. Wind direction had a significant influence on PNC and differed between particles in the fine range (below 2.5 μm) and more coarse particles (up to 10 μm). For fine particles, winds parallel to the canyon were associated with higher PNCs which were attributed to the replenishment of traffic particles. For coarse particles, PNCs were higher from winds perpendicular to the canyon and this was linked to source distribution around the sampling site and the recirculation of pollutants within the canyon. During times when vehicle volumes were high and vehicles were exhibiting stop-start behaviour, if this was combined with low wind speeds, ultrafine PNC was highest. This effect was generally observed during the morning rush hour. Current mass-based legislation does not take into account exposure to the number of particles or the change in population exposure diurnally.

Assessing relative abundance and reproductive success of shrubsteppe raptors

USGS Publications Warehouse

Lehman, Robert N.; Carpenter, L.B.; Steenhof, Karen; Kochert, Michael N.

1998-01-01

From 1991-1994, we quantified relative abundance and reproductive success of the Ferruginous Hawk (Buteo regalis), Northern Harrier (Circus cyaneus), Burrowing Owl (Speotytoc unicularia), and Short-eared Owl (Asio flammeus) on the shrubsteppe plateaus (benchlands) in and near the Snake River Birds of Prey National Conservation Area in southwestern Idaho. To assess relative abundance, we searched randomly selected plots using four sampling methods: point counts, line transects, and quadrats of two sizes. On a persampling-effort basis, transects were slightly more effective than point counts and quadrats for locating raptor nests (3.4 pairs detected/100 h of effort vs. 2.2-3.1 pairs). Random sampling using quadrats failed to detect a Short-eared Owl population increase from 1993 to 1994. To evaluate nesting success, we tried to determine reproductive outcome for all nesting attempts located during random, historical, and incidental nest searches. We compared nesting success estimates based on all nesting attempts, on attempts found during incubation, and the Mayfield model. Most pairs used to evaluate success were pairs found incidentally. Visits to historical nesting areas yielded the highest number of pairs per sampling effort (14.6/100 h), but reoccupancy rates for most species decreased through time. Estimates based on all attempts had the highest sample sizes but probably overestimated success for all species except the Ferruginous Hawk. Estimates of success based on nesting attempts found during incubation had the lowest sample sizes. All three methods yielded biased nesting snccess estimates for the Northern Harrier and Short-eared Owl. The estimate based on pairs found during incubation probably provided the least biased estimate for the Burrowing Owl. Assessments of nesting success were hindered by difficulties in confirming egg laying and nesting success for all species except the Ferruginous hawk.

Evaluation of Different Mineral Filler Aggregates for Asphalt Mixtures

NASA Astrophysics Data System (ADS)

Wasilewska, Marta; Małaszkiewicz, Dorota; Ignatiuk, Natalia

2017-10-01

Mineral filler aggregates play an important role in asphalt mixtures because they fill voids in paving mix and improve the cohesion of asphalt binder. Limestone powder containing over 90% of CaCO3 is the most frequently used type of filler. Waste material from the production of coarse aggregate can be successfully used as a mineral filler aggregate for hot asphalt concrete mixtures as the limestone powder replacement. This paper presents the experimental results of selected properties of filler aggregates which were obtained from rocks with different mineral composition and origin. Five types of rocks were used as a source of the mineral filler aggregate: granite, gabbro, trachybasalt, quartz sandstone and rocks from postglacial deposits. Limestone filler was used in this study as the reference material. The following tests were performed: grading (air jet sieving), quality of fines according to methylene blue test, water content by drying in a ventilated oven, particle density using pyknometer method, Delta ring and ball test, Bitumen Number, fineness determined as Blaine specific surface area. Mineral filler aggregates showed significant differences when they were mixed with bitumen and stiffening effect in Delta ring and ball test was evaluated. The highest values were achieved when gabbro and granite fillers were used. Additionally, Scanning Electron Microscopy (SEM) analysis of grain shape and size was carried out. Significant differences in grain size and shape were observed. The highest non-homogeneity in size was determined for quartz sandstone, gabbro and granite filler. Their Blaine specific surface area was lower than 2800 cm2/g, while for limestone and postglacial fillers with regular and round grains it exceeded 3000 cm2/g. All examined mineral filler aggregates met requirements of Polish National Specification WT-1: 2014 and could be used in asphalt mixtures.

Determinants of mercury contamination in viperine snakes, Natrix maura, in Western Europe.

PubMed

Lemaire, Jérémy; Bustamante, Paco; Olivier, Anthony; Lourdais, Olivier; Michaud, Bruno; Boissinot, Alexandre; Galán, Pedro; Brischoux, François

2018-04-13

The effects of Hg contamination are presumably widespread across the components of aquatic ecosystems, but investigations have been mainly focused on freshwater fish, because this biota represents a major source of Hg for human populations. Yet, the possible bioaccumulation of Hg on other freshwater meso- and apex-predators (e.g., amphibians, reptiles) has been largely overlooked, especially in Western Europe. In this study, the determinants of Hg concentrations were assessed for the viperine snake (Natrix maura) across 6 populations (>130 individuals sampled in 2016 and 2017) in France and Spain. Specifically, body size, sex, and diet were compared with Hg concentrations measured in ventral scales. Overall, N. maura accumulated Hg in their scales. Sex did not seem to influence Hg concentrations in this species. Significant differences in Hg concentrations were observed between study sites, and these differences were likely to be mediated by site-specific diet. Frog-eating individuals were characterized not only by lower mean values of Hg (0.194±0.018μg·g -1 versus 0.386±0.032μg·g -1 for piscivorous individuals), but also by weaker slopes of the body size-Hg relationship as compared to fish-eating snakes, suggesting strong differences in accumulation rates due to food resources. Importantly, the highest slope of the body size-Hg relationship and the highest values of Hg were found in individuals foraging on trout raised by a fish farm, suggesting that fish farming may contribute to Hg contamination in inland freshwater systems. Finally, our results are compared with data on Hg concentrations in other species of aquatic snakes, in order to provide a comparative point for future studies. Copyright © 2018 Elsevier B.V. All rights reserved.

Fluorescence fingerprints and Cu2+-complexing ability of individual molecular size fractions in soil- and waste-borne DOM.

PubMed

Knoth de Zarruk, K; Scholer, G; Dudal, Y

2007-09-01

Land spreading of organic materials introduces large amounts of dissolved organic matter (DOM) into the soil. DOM has the ability to form stable complexes with heavy metals and can facilitate their transport towards the groundwater. The effects on soil processes are difficult to assess, because different DOM components might react differently towards metal ions. The objective of this study was to investigate the fluorescence signature and the Cu2+-binding capacity of individual molecular size fractions of DOM from various sources. DOM extracted from leaf compost, chicken manure, sugar cane vinasse and a fulvic hypercalcaric cambisol was fractionated by the means of dialysis into four molecular size classes: MW<500, 50012000-14000 Da. Vinasse and leaf compost contained around 80% and 70%, respectively, of the total organic carbon in the fractions with low molecular weight (MW<3500 Da); in chicken manure and soil these fractions accounted for 40% and 50% only. Fluorescence was highest in the fraction MW>12000 Da for leaf compost, chicken manure and soil. The opposite result was obtained for vinasse, where the fractions with low molecular weight showed highest fluorescence intensities, distinguishing it from all other samples. Vinasse showed the greatest ability to bind Cu2+ with a resulting complex concentration of 6.31mgl(-1) while in contact with an excess of Cu2+. Leaf compost, soil and chicken manure followed with 2.69, 1.12, and 0.85mgl(-1), respectively. Within vinasse, the fraction MW<500 Da was able to form the most DOM-Cu complexes, indicating the importance of low molecular weight fractions in metal binding.

Influence of genetic background, salinity, and inoculum size on growth of the ichthyotoxic golden alga (Prymnesium parvum).

PubMed

Rashel, Rakib H; Patiño, Reynaldo

2017-06-01

Salinity (5-30) effects on golden alga growth were determined at a standard laboratory temperature (22°C) and one associated with natural blooms (13°C). Inoculum-size effects were determined over a wide size range (100-100,000cellsml -1 ). A strain widely distributed in the USA, UTEX-2797 was the primary study subject but another of limited distribution, UTEX-995 was used to evaluate growth responses in relation to genetic background. Variables examined were exponential growth rate (r), maximum cell density (max-D) and, when inoculum size was held constant (100cellsml -1 ), density at onset of exponential growth (early-D). In UTEX-2797, max-D increased as salinity increased from 5 to ∼10-15 and declined thereafter regardless of temperature but r remained generally stable and only declined at salinity of 25-30. In addition, max-D correlated positively with r and early-D, the latter also being numerically highest at salinity of 15. In UTEX-995, max-D and r responded similarly to changes in salinity - they remained stable at salinity of 5-10 and 5-15, respectively, and declined at higher salinity. Also, max-D correlated with r but not early-D. Inoculum size positively and negatively influenced max-D and r, respectively, in both strains and these effects were significant even when the absolute size difference was small (100 versus 1000 cells ml -1 ). When cultured under similar conditions, UTEX-2797 grew faster and to much higher density than UTEX-995. In conclusion, (1) UTEX-2797's superior growth performance may explain its relatively wide distribution in the USA, (2) the biphasic growth response of UTEX-2797 to salinity variation, with peak abundance at salinity of 10-15, generally mirrors golden alga abundance-salinity associations in US inland waters, and (3) early cell density - whether artificially manipulated or naturally attained - can influence UTEX-2797 bloom potential. Published by Elsevier B.V.

Self-pollination rate and floral-display size in Asclepias syriaca (Common Milkweed) with regard to floral-visitor taxa

PubMed Central

2014-01-01

Background Animals fertilize thousands of angiosperm species whose floral-display sizes can significantly influence pollinator behavior and plant reproductive success. Many studies have measured the interactions among pollinator behavior, floral-display size, and plant reproductive success, but few studies have been able to separate the effects of pollinator behavior and post-pollination processes on angiosperm sexual reproduction. In this study, we utilized the highly self-incompatible pollinium-pollination system of Asclepias syriaca (Common Milkweed) to quantify how insect visitors influenced male reproductive success measured as pollen removal, female reproductive success measured as pollen deposition, and self-pollination rate. We also determined how floral-display size impacts both visitor behavior and self-pollination rate. Results Four insect taxonomic orders visited A. syriaca: Coleoptera, Diptera, Hymenoptera, and Lepidoptera. We focused on three groups of visitor taxa within two orders (Hymenoptera and Lepidoptera) with sample sizes large enough for quantitative analysis: Apis mellifera (Western Honey Bee), Bombus spp. (bumble bees) and lepidopterans (butterflies and moths). Qualitatively, lepidopterans had the highest pollinator importance values, but the large variability in the lepidopteran data precluded meaningful interpretation of much of their behavior. The introduced A. mellifera was the most effective and most important diurnal pollinator with regard to both pollen removal and pollen deposition. However, when considering the self-incompatibility of A. syriaca, A. mellifera was not the most important pollinator because of its high self-pollination rate as compared to Bombus spp. Additionally, the rate of self-pollination increased more rapidly with the number of flowers per inflorescence in A. mellifera than in the native Bombus spp. Conclusions Apis mellifera’s high rate of self-pollination may have significant negative effects on both male and female reproductive successes in A. syriaca, causing different selection on floral-display size than native pollinators. PMID:24958132

Nanosuspension for the delivery of a poorly soluble anti-cancer kinase inhibitor.

PubMed

Danhier, Fabienne; Ucakar, Bernard; Vanderhaegen, Marie-Lyse; Brewster, Marcus E; Arien, Tina; Préat, Véronique

2014-09-01

We hypothesized that nanosuspensions could be promising for the delivery of the poorly water soluble anti-cancer multi-targeted kinase inhibitor, MTKi-327. Hence, the aims of this work were (i) to evaluate the MTKi-327 nanosuspension for parenteral and oral administrations and (ii) to compare this nanosuspension with other nanocarriers in terms of anti-cancer efficacy and pharmacokinetics. Therefore, four formulations of MTKi-327 were studied: (i) PEGylated PLGA-based nanoparticles, (ii) self-assembling PEG₇₅₀-p-(CL-co-TMC) polymeric micelles, (iii) nanosuspensions of MTKi-327; and (iv) Captisol solution (pH=3.5). All the nano-formulations presented a size below 200 nm. Injections of the highest possible dose of the three nano-formulations did not induce any side effects in mice. In contrast, the maximum tolerated dose of the control Captisol solution was 20-fold lower than its highest possible dose. The highest regrowth delay of A-431-tumor-bearing nude mice was obtained with MTKi-327 nanosuspension, administered intravenously, at a dose of 650 mg/kg. After intravenous and oral administration, the AUC₀₋∞ of MTKi-327 nanosuspension was 2.4-fold greater than that of the Captisol solution. Nanosuspension may be considered as an effective anti-cancer MTKi-327 delivery method due to (i) the higher MTKi-327 maximum tolerated dose, (ii) the possible intravenous injection of MTKi-327, (iii) its ability to enhance the administered dose and (iv) its higher efficacy. Copyright © 2014 Elsevier B.V. All rights reserved.

Disinfection effects of undoped and silver-doped ceria powders of nanometer crystallite size

PubMed Central

Tsai, Dah-Shyang; Yang, Tzu-Sen; Huang, Yu-Sheng; Peng, Pei-Wen; Ou, Keng-Liang

2016-01-01

Being endowed with an ability of capturing and releasing oxygen, the ceria surface conventionally assumes the role of catalyzing redox reactions in chemistry. This catalytic effect also makes possible its cytotoxicity toward microorganisms at room temperature. To study this cytotoxicity, we synthesized the doped and undoped ceria particles of 8–9 nm in size using an inexpensive precipitation method and evaluated their disinfecting aptitudes with the turbidimetric and plate count methods. Among the samples being analyzed, the silver-doped ceria exhibits the highest sterilization ability, yet the undoped ceria is the most intriguing. The disinfection effect of undoped ceria is moderate in magnitude, demanding a physical contact between the ceria surface and bacteria cell wall, or the redox catalysis that can damage the cell wall and result in the cell killing. Evidently, this effect is short-range and depends strongly on dispersion of the nanoparticles. In contrast, the disinfection effects of silver-doped ceria reach out several millimeters since it releases silver ions to poison the surrounding microorganisms. Additionally, the aliovalent silver substitution creates more ceria defects. The synergetic combination, silver poisoning and heterogeneous redox catalysis, lifts and extends the disinfecting capability of silver-doped ceria to a superior level. PMID:27330294

Isothermal Treatment Effects on Precipitates and Tensile Properties of an HSLA Steel

NASA Astrophysics Data System (ADS)

Kim, J.-E.; Seol, J.-B.; Choi, W.-M.; Lee, B.-J.; Park, C.-G.

2018-05-01

The relationships between tensile properties and precipitates of a high-strength low-alloy steel depending on the isothermal conditions were investigated. While the isothermally treated steel at 300-500 °C for 1 and 24 h had no significant difference, the steel treated at 500 for 336 h, denoted as 500-336 h, not only showed a decrease in tensile stress but also exhibited a highly increased elongation. Transmission electron microscopy and atom probe tomography were utilized to evaluate the precipitates distribution. The results showed that, in the case of 500-336 h sample, the fraction of precipitates with a radius over 10 nm is the highest and that of a few nano-sized precipitates is the lowest among all samples. It can be explained that the coarsening of originally nano-sized precipitates, occurred by diffusion of dissolved carbon in 500-336 h, mainly affects the tensile behavior.

Characterization of solidifiers used for oil spill remediation.

PubMed

Sundaravadivelu, Devi; Suidan, Makram T; Venosa, Albert D; Rosales, Pablo I

2016-02-01

The physical characteristics and chemical composition of oil spill solidifiers were studied, and correlation of these properties with product effectiveness enabled determination of characteristics that are desirable in a good solidifier. The analyses revealed that the commercial products were primarily comprised of organic polymers and a few trace elements. A natural sorbent, which was composed entirely of plant based matter, was also evaluated, and it had the highest oil removal capacity, but it did not produce a solid mat-like final product. Generally, solidifiers with a carbonate group, pore size greater than 5 μm, and bulk densities lower than 0.3 g cm(-3) were found to have better efficiency and produced a cohesive rubbery final product that facilitated removal compared to sorbents. The importance of bulk density and pore size in the performance of the solidifier suggest that the primary mechanism of action was likely physical sorption. Copyright © 2015 Elsevier Ltd. All rights reserved.

Scaling effects in sodium zirconium silicate phosphate (Na 1+ xZr 2Si xP 3- xO 12) ion-conducting thin films

DOE PAGES

Ihlefeld, Jon F.; Gurniak, Emily; Jones, Brad H.; ...

2016-05-04

Preparation of sodium zirconium silicate phosphate (NaSICon), Na 1+xZr 2Si xP 3–xO 12 (0.25 ≤ x ≤ 1.0), thin films has been investigated via a chemical solution approach on platinized silicon substrates. Increasing the silicon content resulted in a reduction in the crystallite size and a reduction in the measured ionic conductivity. Processing temperature was also found to affect microstructure and ionic conductivity with higher processing temperatures resulting in larger crystallite sizes and higher ionic conductivities. The highest room temperature sodium ion conductivity was measured for an x = 0.25 composition at 2.3 × 10 –5 S/cm. In conclusion, themore » decreasing ionic conductivity trends with increasing silicon content and decreasing processing temperature are consistent with grain boundary and defect scattering of conducting ions.« less

The effects of density dependent resource limitation on size of wild reindeer.

PubMed

Skogland, Terje

1983-11-01

A density-dependent decrement in size for wild reindeer from 12 different Norwegian herds at 16 different densities was shown using lower jawbone-length as the criterion of size. This criterion was tested and found to adequately predict body size of both bucks and does. Lactation in does did not affect jaw length but significantly affected dressed weights.A decrement in the size of does as a result of gross density was found. This size decrement was further analysed in relation to the habitat densities in winter (R 2 =0.85) and in summer (R 2 =0.75) separately, in order to estimate the relative effects of each factor. For herds with adequate food in winter (no signs of overgrazing of lichens) density in relation to summer habitat and mires yielded the highest predictive power in a multiple regression. For herds with adequate summer pastures, densities per winter habitat and lichen volumes showed likewise a highly significant correlation. The inclusion of the lichen volume data in the regression increased its predictive power. The major effect of resource limitation was to delay the time of calving because a maternal carry-over effect allowed the calf a shorter period of growth to be completed during its first summer. Neonate size at birth was highly correlated with maternal size regardless of the mean calving date although the latter was significantly delayed for small-sized does in food resource-limited herds. Likewise the postnatal growth rate of all calves were not significantly different during 50 days postpartum regardless of maternal conditions in winter feeding. The summer growth rates of bucks ≧1 year did not vary significantly between herds. The age of maturity of food resource-limited does was delayed by one year and growth ceased after the initiation of reproduction. This shows that under conditions of limited resources the does with delayed births of calves allocated less energy to body growth simply because they had less time to replenish body reserves once they were freed of the energetic demands of lactation. The overriding effects of such limitation of food resources is thus to produce a time-lag for the completition of all the important life-history events, such as growth, maintenance and reproduction. From a theoretical point of view, i.e. according to the reproductive effort model their only option is to try to overcome this time limitation to reproductive success.

Spatial Biodiversity Patterns of Madagascar's Amphibians and Reptiles

PubMed Central

Brown, Jason L.; Sillero, Neftali; Glaw, Frank; Bora, Parfait; Vieites, David R.; Vences, Miguel

2016-01-01

Madagascar has become a model region for testing hypotheses of species diversification and biogeography, and many studies have focused on its diverse and highly endemic herpetofauna. Here we combine species distribution models of a near-complete set of species of reptiles and amphibians known from the island with body size data and a tabulation of herpetofaunal communities from field surveys, compiled up to 2008. Though taxonomic revisions and novel distributional records arose since compilation, we are confident that the data are appropriate for inferring and comparing biogeographic patterns among these groups of organisms. We observed species richness of both amphibians and reptiles was highest in the humid rainforest biome of eastern Madagascar, but reptiles also show areas of high richness in the dry and subarid western biomes. In several amphibian subclades, especially within the Mantellidae, species richness peaks in the central eastern geographic regions while in reptiles different subclades differ distinctly in their richness centers. A high proportion of clades and subclades of both amphibians and reptiles have a peak of local endemism in the topographically and bioclimatically diverse northern geographic regions. This northern area is roughly delimited by a diagonal spanning from 15.5°S on the east coast to ca. 15.0°S on the west coast. Amphibian diversity is highest at altitudes between 800–1200 m above sea-level whereas reptiles have their highest richness at low elevations, probably reflecting the comparatively large number of species specialized to the extended low-elevation areas in the dry and subarid biomes. We found that the range sizes of both amphibians and reptiles strongly correlated with body size, and differences between the two groups are explained by the larger body sizes of reptiles. However, snakes have larger range sizes than lizards which cannot be readily explained by their larger body sizes alone. Range filling, i.e., the amount of suitable habitat occupied by a species, is less expressed in amphibians than in reptiles, possibly reflecting their lower dispersal capacity. Taxonomic composition of communities assessed by field surveys is largely explained by bioclimatic regions, with communities from the dry and especially subarid biomes distinctly differing from humid and subhumid biomes. PMID:26735688

Spatial Biodiversity Patterns of Madagascar's Amphibians and Reptiles.

PubMed

Brown, Jason L; Sillero, Neftali; Glaw, Frank; Bora, Parfait; Vieites, David R; Vences, Miguel

2016-01-01

Madagascar has become a model region for testing hypotheses of species diversification and biogeography, and many studies have focused on its diverse and highly endemic herpetofauna. Here we combine species distribution models of a near-complete set of species of reptiles and amphibians known from the island with body size data and a tabulation of herpetofaunal communities from field surveys, compiled up to 2008. Though taxonomic revisions and novel distributional records arose since compilation, we are confident that the data are appropriate for inferring and comparing biogeographic patterns among these groups of organisms. We observed species richness of both amphibians and reptiles was highest in the humid rainforest biome of eastern Madagascar, but reptiles also show areas of high richness in the dry and subarid western biomes. In several amphibian subclades, especially within the Mantellidae, species richness peaks in the central eastern geographic regions while in reptiles different subclades differ distinctly in their richness centers. A high proportion of clades and subclades of both amphibians and reptiles have a peak of local endemism in the topographically and bioclimatically diverse northern geographic regions. This northern area is roughly delimited by a diagonal spanning from 15.5°S on the east coast to ca. 15.0°S on the west coast. Amphibian diversity is highest at altitudes between 800-1200 m above sea-level whereas reptiles have their highest richness at low elevations, probably reflecting the comparatively large number of species specialized to the extended low-elevation areas in the dry and subarid biomes. We found that the range sizes of both amphibians and reptiles strongly correlated with body size, and differences between the two groups are explained by the larger body sizes of reptiles. However, snakes have larger range sizes than lizards which cannot be readily explained by their larger body sizes alone. Range filling, i.e., the amount of suitable habitat occupied by a species, is less expressed in amphibians than in reptiles, possibly reflecting their lower dispersal capacity. Taxonomic composition of communities assessed by field surveys is largely explained by bioclimatic regions, with communities from the dry and especially subarid biomes distinctly differing from humid and subhumid biomes.

Reporting of research quality characteristics of studies published in 6 major clinical dental specialty journals.

PubMed

Pandis, Nikolaos; Polychronopoulou, Argy; Madianos, Phoebus; Makou, Margarita; Eliades, Theodore

2011-06-01

The objective of this article was to record reporting characteristics related to study quality of research published in major specialty dental journals with the highest impact factor (Journal of Endodontics, Journal of Oral and Maxillofacial Surgery, American Journal of Orthodontics and Dentofacial Orthopedics; Pediatric Dentistry, Journal of Clinical Periodontology, and International Journal of Prosthetic Dentistry). The included articles were classified into the following 3 broad subject categories: (1) cross-sectional (snap-shot), (2) observational, and (3) interventional. Multinomial logistic regression was conducted for effect estimation using the journal as the response and randomization, sample calculation, confounding discussed, multivariate analysis, effect measurement, and confidence intervals as the explanatory variables. The results showed that cross-sectional studies were the dominant design (55%), whereas observational investigations accounted for 13%, and interventions/clinical trials for 32%. Reporting on quality characteristics was low for all variables: random allocation (15%), sample size calculation (7%), confounding issues/possible confounders (38%), effect measurements (16%), and multivariate analysis (21%). Eighty-four percent of the published articles reported a statistically significant main finding and only 13% presented confidence intervals. The Journal of Clinical Periodontology showed the highest probability of including quality characteristics in reporting results among all dental journals. Copyright © 2011 Elsevier Inc. All rights reserved.

Impact of Annular Size on Outcomes After Surgical or Transcatheter Aortic Valve Replacement.

PubMed

Deeb, G Michael; Chetcuti, Stanley J; Yakubov, Steven J; Patel, Himanshu J; Grossman, P Michael; Kleiman, Neal S; Heiser, John; Merhi, William; Zorn, George L; Tadros, Peter N; Petrossian, George; Robinson, Newell; Mumtaz, Mubashir; Gleason, Thomas G; Huang, Jian; Conte, John V; Popma, Jeffrey J; Reardon, Michael J

2018-04-01

This analysis evaluates the relationship of annular size to hemodynamics and the incidence of prosthesis-patient mismatch (PPM) in surgical aortic valve replacement (SAVR) and transcatheter aortic valve replacement (TAVR) patients. The CoreValve US Pivotal High Risk Trial, described previously, compared TAVR using a self-expanding valve with SAVR. Multislice computed tomography was used to categorize TAVR and SAVR subjects according to annular perimeter-derived diameter: large (≥26 mm), medium (23 to <26 mm), and small (<23 mm). Hemodynamics, PPM, and clinical outcomes were assessed. At all postprocedure visits, mean gradients were significantly lower for TAVR compared with SAVR in small and medium size annuli (p < 0.001). Annular size was significantly associated with mean gradient after SAVR, with small annuli having the highest gradients (p < 0.05 at all timepoints); gradients were similar across all annular sizes after TAVR. In subjects receiving SAVR, the frequency of PPM was significantly associated with annular size, with small annuli having the greatest incidence. No difference in PPM incidence by annular sizing was observed with TAVR. In addition, TAVR subjects had significantly less PPM than SAVR subjects in small and medium annuli (p < 0.001), with no difference in the incidence of PPM between TAVR and SAVR in large annuli (p = 0.10). Annular size has a significant effect on hemodynamics and the incidence of PPM in SAVR subjects, not observed in TAVR subjects. With respect to annular size, TAVR results in better hemodynamics and less PPM for annuli less than 26 mm and should be strongly considered when choosing a tissue valve for small and medium size annuli. Copyright © 2018 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

Concentrate supplementations of grazing pregnant Kalahari Red goats: Effects on pregnancy variables, reproductive performance, birth types and weight of kids.

PubMed

Oderinwale, O A; Oluwatosin, B O; Sowande, O S; Bemji, M N; Amosu, S D; Sanusi, G O

2017-08-01

A study was conducted for 22 weeks to determine the effects of concentrate supplementations at three crude protein (CP) levels, i.e. low protein diet-LPD 12.42% CP (124.93 g day -1 ); medium protein diet-MPD 14.18% CP (145.87 g day -1 ) and high protein diet-HPD 16.35% CP (168.19 g day -1 ) on some pregnancy variables, reproductive performance, birth types and weight of kids kidded by pregnant Kalahari Red goats grazed on Chloris gayana. Thirty-three matured Kalahari Red goats of first parity within age range of 2 to 2 1 / 2  years with an average body weight of 38.10 ± 1.13 kg were randomly allotted to the diets with 11 goats per treatment. Data obtained were subjected to analysis of variance in a completely randomised design. It was observed that goats fed HPD had the highest (p < 0.05) values for products of pregnancy (10.35 kg) taken within 24hour before kidding and foetal growth rate (88.37 g day -1 ) during pregnancy. Goats fed MPD had the lowest values (p < 0.05) of 9.28 kg and 80.07 g day -1 for each of the respective parameters. Afterbirth weight was also the highest and lowest (p < 0.05) for goats supplemented with HPD (3.38 kg) and MPD (3.04 kg), respectively. On the other hand, MPD-supplemented goats had the highest values (p < 0.05) for litter size (2.14) and litter weight (6.80 kg) at birth, the value which was the least for HPD supplementation. From the results obtained from this study, it could be concluded that concentrate diet supplementation with 14.18% CP improved litter size and weight at birth with resultant reduction in weights of pregnancy variables of pregnant Kalahari Red goats grazed on Rhodes grass.

Land cover of oases and forest in XinJiang, China retrieved from ASTER data

NASA Astrophysics Data System (ADS)

Buhe, Aosier; Tsuchiya, K.; Kaneko, M.; Ohtaishi, N.; Halik, Mahmut

ASTER aboard NASA’s satellite Terra is a high-resolution multispectral radiometer of 14 bands. The spatial resolution is 15 m in VNIR, 30 m in SWIR and 90 m in TIR spectra, respectively. With the data observed with ASTER, the land cover classification is produced for the Tarim Diversifolious Poplar Protection Area along the Tarim River in the northern Tarim Basin (Taklamakan Desert) in XinJiang, China. The classification of the vegetation (plants) in the arid and semiarid regions using remote-sensing technology is very difficult. Because the cause has low vegetable cover density and the influence of reflection from background soil is large. ASTER data are effective in studying the spectrum characteristics of land cover in arid and semiarid regions. The sensor has several bands in the shortwave infrared wavelength region that is designed for exploration of earth resources and study of the arid and semiarid region natural environment. However, we are not clear combination of which band is the most effective in research of the arid region like the Taklamakan desert in the data of 14 bands of ASTER. The optimum index factor (OIF), based on total variance within bands and correlation coefficient between bands, is a statistical approach to rank all possible three-band combinations. In the process of analyzing the data, the pixel sizes of all the data are converted (layer stacking and re-sampling) into consistent same size of 15 m. The three-band composite with the largest OIF value will have most information (as measured by variance) with the least amount of duplication (as measured by correlation). We used the OIF technique to rank all three-band combinations of ASTER original 14-band data over Tarim River Poplar Protection Area. Our study indicates that RGB color overlay using atmospheric corrected ASTER original bands 2, 3 (VNIR), and 6 (SWIR) has the highest OIF. When NDVI is considered as one ASTER band, highest OIF will have by carrying out bands 3 (VNIR), 4 (SWIR), and NDVI. In this study, we used highest OIF (bands 3, 4, and NDVI) succeeded in extraction of Tarim River Poplar Forest.

Accumulation of six metals in the mangrove crab Ucides cordatus (Crustacea: Ucididae) and its food source, the red mangrove Rhizophora mangle (Angiosperma: Rhizophoraceae).

PubMed

Pinheiro, Marcelo Antonio Amaro; Silva, Pablo Pena Gandara E; Duarte, Luis Felipe de Almeida; Almeida, Alaor Aparecido; Zanotto, Flavia Pinheiro

2012-07-01

The crab Ucides cordatus and the red mangrove Rhizophora mangle are endemic mangrove species and potential bio-accumulators of metals. This study quantified the accumulation of six metals (Cd, Cr, Cu, Hg, Mn and Pb) in different organs (claw muscle, hepatopancreas and gills) of U. cordatus, as well as in different maturation stages of the leaves (buds, green mature, and pre-abscission senescent) of R. mangle. Samples were collected from mangrove areas in Cubatão, state of São Paulo, a heavily polluted region in Brazil. Data for metal contents in leaves were evaluated by one-way ANOVA; while for crabs a factorial ANOVA was used to investigate the effect of different tissues, animal size and the interactions between them. Means were compared by Tukey test at five percent, and the association between the metal concentrations in each crab organ, depending on the size, was evaluated by Pearson's linear correlation coefficient (r). Concentrations of Pb and Hg were undetectable for the different leaf stages and crab tissues, while Cd concentrations were undetectable in the leaf stages. In general, the highest accumulation of metals in R. mangle leaves occurred in pre-abscission senescent and green mature leaves, except for Cu, which was found in the highest concentrations in buds and green mature leaves. For the crab, Cd, Cu, Cr and Mn were present in concentrations above the detection limit, with the highest accumulation in the hepatopancreas, followed by the gills. Cu was accumulated mostly in the gills. Patterns of bioaccumulation between the crab and the mangrove tree differed for each metal, probably due to the specific requirements of each organism for essential metals. However, there was a close and direct relationship between metal accumulation in the mangrove trees and in the crabs feeding on them. Tissues of R. mangle leaves and U. cordatus proved effective for monitoring metals, acting as important bioindicators of mangrove areas contaminated by various metals. Copyright © 2012 Elsevier Inc. All rights reserved.

Supercapacitor electrode materials with hierarchically structured pores from carbonization of MWCNTs and ZIF-8 composites.

PubMed

Li, Xueqin; Hao, Changlong; Tang, Bochong; Wang, Yue; Liu, Mei; Wang, Yuanwei; Zhu, Yihua; Lu, Chenguang; Tang, Zhiyong

2017-02-09

Due to their high specific surface area and good electric conductivity, nitrogen-doped porous carbons (NPCs) and carbon nanotubes (CNTs) have attracted much attention for electrochemical energy storage applications. In the present work, we firstly prepared MWCNT/ZIF-8 composites by decoration of zeolitic imidazolate frameworks (ZIF-8) onto the surface of multi-walled CNTs (MWCNTs), then obtained MWCNT/NPCs by the direct carbonization of MWCNT/ZIF-8. By controlling the reaction conditions, MWCNT/ZIF-8 with three different particle sizes were synthesized. The effect of NPCs size on capacitance performance has been evaluated in detail. The MWCNT/NPC with large-sized NPC (MWCNT/NPC-L) displayed the highest specific capacitance of 293.4 F g -1 at the scan rate of 5 mV s -1 and only lost 4.2% of capacitance after 10 000 cyclic voltammetry cycles, which was attributed to the hierarchically structured pores, N-doping and high electrical conductivity. The studies of symmetric two-electrode supercapacitor cells also confirmed MWCNT/NPC-L as efficient electrode materials that have good electrochemical performance, especially for high-rate applications.

Planar-Structure Perovskite Solar Cells with Efficiency beyond 21.

PubMed

Jiang, Qi; Chu, Zema; Wang, Pengyang; Yang, Xiaolei; Liu, Heng; Wang, Ye; Yin, Zhigang; Wu, Jinliang; Zhang, Xingwang; You, Jingbi

2017-12-01

Low temperature solution processed planar-structure perovskite solar cells gain great attention recently, while their power conversions are still lower than that of high temperature mesoporous counterpart. Previous reports are mainly focused on perovskite morphology control and interface engineering to improve performance. Here, this study systematically investigates the effect of precise stoichiometry, especially the PbI 2 contents on device performance including efficiency, hysteresis and stability. This study finds that a moderate residual of PbI 2 can deliver stable and high efficiency of solar cells without hysteresis, while too much residual PbI 2 will lead to serious hysteresis and poor transit stability. Solar cells with the efficiencies of 21.6% in small size (0.0737 cm 2 ) and 20.1% in large size (1 cm 2 ) with moderate residual PbI 2 in perovskite layer are obtained. The certificated efficiency for small size shows the efficiency of 20.9%, which is the highest efficiency ever recorded in planar-structure perovskite solar cells, showing the planar-structure perovskite solar cells are very promising. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

A meta-analysis of temperament in eating disorders.

PubMed

Atiye, Minna; Miettunen, Jouko; Raevuori-Helkamaa, Anu

2015-03-01

Although suggested as an important contributor to the development and maintenance of eating disorders, temperament has not previously been studied adopting a meta-analytical approach. We therefore pooled data (N = 14 studies; N = 3315 cases, N = 3395 controls) on Cloninger's temperament traits (novelty seeking, harm avoidance, reward dependence and persistence) in anorexia nervosa (AN), bulimia nervosa (BN), binge eating disorder (BED) and eating disorders not otherwise specified. Persistence was significantly higher than in the controls in all eating disorders except for BED the highest levels being observed in AN. Correspondingly, the highest effect sizes for harm avoidance were seen in AN. Novelty seeking was significantly elevated relative to the controls only in BN. Harm avoidance was significantly lower, and reward dependence was significantly higher in individuals who had recovered from AN than in those who remained ill. Future studies with a longitudinal design are needed to explore the temporal relationships between eating disorders and temperament traits. Copyright © 2014 John Wiley & Sons, Ltd and Eating Disorders Association.

Cashew gum and inulin: New alternative for ginger essential oil microencapsulation.

PubMed

Fernandes, Regiane Victória de Barros; Botrel, Diego Alvarenga; Silva, Eric Keven; Borges, Soraia Vilela; Oliveira, Cassiano Rodrigues de; Yoshida, Maria Irene; Feitosa, Judith Pessoa de Andrade; de Paula, Regina Célia Monteiro

2016-11-20

This study aimed to evaluate the effect of partial replacement of cashew gum by inulin used as wall materials, on the characteristics of ginger essential oil microencapsulated by spray drying with ultrasound assisted emulsions. The characterization of particles was evaluated as encapsulation efficiency and particle size. In addition, the properties of the microcapsules were studied through FTIR analysis, adsorption isotherms, thermal gravimetric analysis, X-ray and scanning electron microscopy. It was found that the solubility of the treatments was affected by the composition of the wall material and reached higher values (89.80%) when higher inulin concentrations were applied. The encapsulation efficiency (15.8%) was lower at the highest inulin concentration. The particles presented amorphous characteristics and treatment with cashew gum as encapsulant exhibited the highest water absorption at high water activity. The cashew gum and inulin matrix (3:1(w/w) ratio) showed the best characteristics regarding the encapsulation efficiency and morphology, showing no cracks in the structure. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effect of ozonolysis pretreatment parameters on the sugar release, ozone consumption and ethanol production from sugarcane bagasse.

PubMed

Travaini, Rodolfo; Barrado, Enrique; Bolado-Rodríguez, Silvia

2016-08-01

A L9(3)(4) orthogonal array (OA) experimental design was applied to study the four parameters considered most important in the ozonolysis pretreatment (moisture content, ozone concentration, ozone/oxygen flow and particle size) on ethanol production from sugarcane bagasse (SCB). Statistical analysis highlighted ozone concentration as the highest influence parameter on reaction time and sugars release after enzymatic hydrolysis. The increase on reaction time when decreasing the ozone/oxygen flow resulted in small differences of ozone consumptions. Design optimization for sugars release provided a parameters combination close to the best experimental run, where 77.55% and 56.95% of glucose and xylose yields were obtained, respectively. When optimizing the grams of sugar released by gram of ozone, the highest influence parameter was moisture content, with a maximum yield of 2.98gSUGARS/gO3. In experiments on hydrolysates fermentation, Saccharomyces cerevisiae provided ethanol yields around 80%, while Pichia stipitis was completely inhibited. Copyright © 2016 Elsevier Ltd. All rights reserved.

Thyroid Nodule Size at Ultrasound as a Predictor of Malignancy and Final Pathologic Size.

PubMed

Cavallo, Allison; Johnson, Daniel N; White, Michael G; Siddiqui, Saaduddin; Antic, Tatjana; Mathew, Melvy; Grogan, Raymon H; Angelos, Peter; Kaplan, Edwin L; Cipriani, Nicole A

2017-05-01

Thyroid-related mortality has remained constant despite the increasing incidence of thyroid carcinoma. Most thyroid nodules are benign; therefore, ultrasound and fine needle aspiration (FNA) are integral in cancer screening. We hypothesize that increased nodule size at ultrasound does not predict malignancy and correlation between nodule size at ultrasound and pathologic exam is good. Resected thyroids with preoperative ultrasounds were identified. Nodule size at ultrasound, FNA diagnosis by Bethesda category, size at pathologic examination, and final histologic diagnosis were recorded. Nodule characteristics at ultrasound and FNA diagnoses were correlated with gross characteristics and histologic diagnoses. Nodules for which correlation could not be established were excluded. Of 1003 nodules from 659 patients, 26% were malignant. Nodules <2 cm had the highest malignancy rate (∼30%). Risk was similar (∼20%) for nodules ≥2 cm. Of the 548 subject to FNA, 38% were malignant. Decreasing malignancy rates were observed with increasing size (57% for nodules <1 cm to 20% for nodules >6 cm). At ultrasound size cutoffs of 2, 3, 4, and 5 cm, smaller nodules had higher malignancy rates than larger nodules. Of the 455 not subject to FNA, 11% were malignant. Ultrasound size alone is a poor predictor of malignancy, but a relatively good predictor of final pathologic size (R 2  = 0.748), with less correlation at larger sizes. In nodules subject to FNA, false negative diagnoses were highest (6-8%) in nodules 3-6 cm, mostly due to encapsulated follicular variant of papillary carcinoma. Thyroid nodule size is inversely related to malignancy risk, as larger nodules have lower malignancy rates. However, the relationship of size to malignancy varies by FNA status. All nodules (regardless of FNA status) demonstrate a risk trough at ≥2 cm. Nodules subject to FNA show step-wise decline in malignancy rates by size, demonstrating that size alone should not be considered as an independent risk factor. Size at ultrasound shows relatively good correlation with final pathologic size. False negative rates are low in this series. Lesions with the appropriate constellation of clinical and radiographic findings should undergo FNA regardless of size. Both size and FNA diagnosis should influence the clinical decision-making process.

Effect of heat bed temperature of 3D bioprinter to hardness and compressive strength of scaffold bovine hydroxyapatite

NASA Astrophysics Data System (ADS)

Triyono, Joko; Pratama, Aditya; Sukanto, Heru; Nugroho, Yohanes; Wijayanta, Agung Tri

2018-02-01

This study aimed to investigate the effect of heat bed temperature of 3D bioprinter toward compressive strength and hardness bovine bone hydroxyapatite scaffold for bone filler applications. BHA-glycerin mixed with a ratio of 1:1, and keep it for 24 hours. After the homogenization process acquired, bio-Ink with shaped slurry will be used as a material for a 3D printer. The printing process with a temperature variation have performed by setting up heat bed temperature. After printing process was completed, the 3D scaffold was detained on the heat bed for 10 minutes before being picked up. The test results in this study had the lowest hardness value of 9.82±0.62 VHN and the highest number of 24.32±0.99 VHN. The compressive strength testing had the lowest value of 1.62±0.16 MPa with the highest number of 5.67±0.39 MPa. Pore observation using a scanning electron microscope. The result shows that the size of the pores were not much different, that was ±100-200 µm. This observation also indicated that the pore form was square pores.

Feeding behaviour of the nauplii of the marine calanoid copepod Paracartia grani Sars: Functional response, prey size spectrum, and effects of the presence of alternative prey.

PubMed

Helenius, Laura K; Saiz, Enric

2017-01-01

Laboratory feeding experiments were conducted to study the functional response and prey size spectrum of the young naupliar stages of the calanoid copepod Paracartia grani Sars. Experiments were conducted on a range of microalgal prey of varying sizes and motility patterns. Significant feeding was found in all prey of a size range of 4.5-19.8 μm, with Holling type III functional responses observed for most prey types. The highest clearance rates occurred when nauplii fed on the dinoflagellate Heterocapsa sp. and the diatom Thalassiosira weissflogii (respectively, 0.61 and 0.70 mL ind-1 d-1), suggesting an optimal prey:predator ratio of 0.09. Additional experiments were conducted to examine the effects of the presence of alternative prey (either Heterocapsa sp. or Gymnodinium litoralis) on the functional response to the haptophyte Isochrysis galbana. In the bialgal mixtures, clearance and ingestion rates of I. galbana along the range of the functional response were significantly reduced as a result of selectivity towards the larger, alternative prey. Paradoxically, relatively large prey trigger a perception response in the nauplii, but most likely such prey cannot be completely ingested and a certain degree of sloppy feeding may occur. Our results are further evidence of the complex prey-specific feeding interactions that are likely to occur in natural assemblages with several available prey types.

Size-related cytotoxicological aspects of polyvinylpyrrolidone-capped platinum nanoparticles.

PubMed

Buchtelova, Hana; Dostalova, Simona; Michalek, Petr; Krizkova, Sona; Strmiska, Vladislav; Kopel, Pavel; Hynek, David; Richtera, Lukas; Ridoskova, Andrea; Adam, Pavlina; Kynicky, Jindrich; Brtnicky, Martin; Heger, Zbynek; Adam, Vojtech

2017-07-01

The nanotechnological concept is based on size-dependent properties of particles in the 1-100 nm range. Nevertheless, the connection between their size and effect is still not clear. Thus, we focused on reductive colloidal synthesis, characterization and biological testing of Pt nanoparticles (PtNPs) capped with biocompatible polymer polyvinylpyrrolidone (PVP). Synthesized PtNPs were of 3 different primary sizes (approx. ∼10; ∼14 and > 20 nm) and demonstrated exceptional haemocompatibility. In vitro treatment of three different types of malignant cells (prostate - LNCaP, breast - MDA-MB-231 and neuroblastoma - GI-ME-N) revealed that even marginal differences in PtNPs diameter resulted in changes in their cytotoxicity. The highest cytotoxicity was observed using the smallest PtNPs-10, where 24IC 50 was lower (3.1-6.2 μg/mL) than for cisplatin (8.1-19.8 μg/mL). In contrast to MDA-MB-231 and LNCaP cells, in GI-ME-N cells PtNPs caused noticeable changes in their cellular structure without influencing their viability. Post-exposure analyses revealed that PtNPs-29 and PtNPs-40 were capable of forming considerably higher amount of reactive oxygen species with consequent stimulation of expression of metallothionein (MT1/2 and MT3), at both mRNA and protein level. Overall, our pilot study demonstrates that in the nanoscaled world even the smallest differences can have crucial biological effect. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effect of copper sulphate treatment on natural phytoplanktonic communities.

PubMed

Le Jeune, Anne-Hélène; Charpin, Marie; Deluchat, Véronique; Briand, Jean-François; Lenain, Jean-François; Baudu, Michel; Amblard, Christian

2006-12-01

Copper sulphate treatment is widely used as a global and empirical method to remove or control phytoplankton blooms without precise description of the impact on phytoplanktonic populations. The effects of two copper sulphate treatments on natural phytoplanktonic communities sampled in the spring and summer seasons, were assessed by indoor mesocosm experiments. The initial copper-complexing capacity of each water sample was evaluated before each treatment. The copper concentrations applied were 80 microg l(-1) and 160 microg l(-1) of copper, below and above the water complexation capacity, respectively. The phytoplanktonic biomass recovered within a few days after treatment. The highest copper concentration, which generated a highly toxic environment, caused a global decrease in phytoplankton diversity, and led to the development and dominance of nanophytoplanktonic Chlorophyceae. In mesocosms treated with 80 microg l(-1) of copper, the effect on phytoplanktonic community size-class structure and composition was dependent on seasonal variation. This could be related to differences in community composition, and thus to species sensitivity to copper and to differences in copper bioavailability between spring and summer. Both treatments significantly affected cyanobacterial biomass and caused changes in the size-class structure and composition of phytoplanktonic communities which may imply modifications of the ecosystem structure and function.

Polyethylenimine-modified curcumin-loaded mesoporus silica nanoparticle (MCM-41) induces cell death in MCF-7 cell line.

PubMed

Harini, Lakshminarasimhan; Karthikeyan, Bose; Srivastava, Sweta; Suresh, Srinag Bangalore; Ross, Cecil; Gnanakumar, Georgepeter; Rajagopal, Srinivasan; Sundar, Krishnan; Kathiresan, Thandavarayan

2017-02-01

Breast cancer accounts for the first highest mortality rate in India and second in world. Though current treatment strategies are effectively killing cancer cells, they also end in causing severe side effects and drug resistance. Curcumin is a nutraceutical with multipotent activity but its insolubility in water limits its therapeutic potential as an anti-cancer drug. The hydrophilicity of curcumin could be increased by nanoformulation or changing its functional groups. In this study, curcumin is loaded on mesoporous silica nanoparticle and its anti-cancer activity is elucidated with MCF-7 cell death. Structural characteristics of Mobil Composition of Matter - 41(MCM-41) as determined by high-resolution transmission electron microscopy (HR-TEM) shows that MCM-41 size ranges from 100 to 200 nm diameters with pore size 2-10 nm for drug adsorption. The authors found 80-90% of curcumin is loaded on MCM-41 and curcumin is released efficiently at pH 3.0. The 50 µM curcumin-loaded MCM-41 induced 50% mortality of MCF-7 cells. Altogether, their results suggested that increased curcumin loading and sustained release from MCM-41 effectively decreased cell survival of MCF-7 cells in vitro.

Alzheimer Disease Biomarkers as Outcome Measures for Clinical Trials in MCI.

PubMed

Caroli, Anna; Prestia, Annapaola; Wade, Sara; Chen, Kewei; Ayutyanont, Napatkamon; Landau, Susan M; Madison, Cindee M; Haense, Cathleen; Herholz, Karl; Reiman, Eric M; Jagust, William J; Frisoni, Giovanni B

2015-01-01

The aim of this study was to compare the performance and power of the best-established diagnostic biological markers as outcome measures for clinical trials in patients with mild cognitive impairment (MCI). Magnetic resonance imaging, F-18 fluorodeoxyglucose positron emission tomography markers, and Alzheimer's Disease Assessment Scale-cognitive subscale were compared in terms of effect size and statistical power over different follow-up periods in 2 MCI groups, selected from Alzheimer's Disease Neuroimaging Initiative data set based on cerebrospinal fluid (abnormal cerebrospinal fluid Aβ1-42 concentration-ABETA+) or magnetic resonance imaging evidence of Alzheimer disease (positivity to hippocampal atrophy-HIPPO+). Biomarkers progression was modeled through mixed effect models. Scaled slope was chosen as measure of effect size. Biomarkers power was estimated using simulation algorithms. Seventy-four ABETA+ and 51 HIPPO+ MCI patients were included in the study. Imaging biomarkers of neurodegeneration, especially MR measurements, showed highest performance. For all biomarkers and both MCI groups, power increased with increasing follow-up time, irrespective of biomarker assessment frequency. These findings provide information about biomarker enrichment and outcome measurements that could be employed to reduce MCI patient samples and treatment duration in future clinical trials.

GMR effect in CuCo annealed melt-spun ribbons.

PubMed

Murillo, N; Grande, H; Etxeberria, I; Del Val, J J; González, J; Arana, S; Gracia, F J

2004-11-01

A thorough microstructural and magnetic analysis has been performed on as-quenched and annealed (475 and 525 degrees C, 1 hour) melt-spun Cu100-xCox (x = 10 and 15) granular alloys, presenting a giant magnetoresistance (GMR) effect. The annealed samples are inhomogeneous with respect to the Co-particle sizes and interparticles distances and, therefore, these particles present superparamagnetic and ferromagnetic behaviours, which determine the GMR response. The samples x = 15, treated at 525 degrees C during 1 hour, presented the best GMR ratio (approximately 5% at room temperature to be the highest value approaching roughly to the saturation under an applied magnetic field of 15 KOe), with the coexistence of Co-particles with both kinds of magnetic behaviour.

Acidic Mesoporous Zeolite ZSM-5 Supported Cu Catalyst with Good Catalytic Performance in the Hydroxysulfurization of Styrenes with Disulfides.

PubMed

Hu, Jun; Zhu, Chaojie; Xia, Feifei; Fang, Zhongxue; Yang, Fengli; Weng, Jushi; Yao, Pengfei; Zheng, Chunzhi; Dong, Hai; Fu, Wenqian

2017-12-19

Development of highly active heterogeneous catalysts is an effective strategy for modern organic synthesis chemistry. In this work, acidic mesoporous zeolite ZSM-5 (HZSM-5-M), acidic-free mesoporous zeolite TS-1 (TS-1-M), and basic ETS-10 zeolite supported metal Cu catalysts were prepared to investigate their catalytic performances in the hydroxysulfurization of styrenes with diaryl disulfides. The effect of pore size and acidities of the supports, as well as the Cu species electronic properties of the catalysts on reaction activity were investigated. The results show that Cu⁺ and Cu 2+ binded on HZSM-5-M show the highest activity and product selectivity for the desired β -hydroxysulfides compounds.

Acidic Mesoporous Zeolite ZSM-5 Supported Cu Catalyst with Good Catalytic Performance in the Hydroxysulfurization of Styrenes with Disulfides

PubMed Central

Hu, Jun; Zhu, Chaojie; Xia, Feifei; Fang, Zhongxue; Yang, Fengli; Weng, Jushi; Yao, Pengfei; Zheng, Chunzhi; Dong, Hai; Fu, Wenqian

2017-01-01

Development of highly active heterogeneous catalysts is an effective strategy for modern organic synthesis chemistry. In this work, acidic mesoporous zeolite ZSM-5 (HZSM-5-M), acidic-free mesoporous zeolite TS-1 (TS-1-M), and basic ETS-10 zeolite supported metal Cu catalysts were prepared to investigate their catalytic performances in the hydroxysulfurization of styrenes with diaryl disulfides. The effect of pore size and acidities of the supports, as well as the Cu species electronic properties of the catalysts on reaction activity were investigated. The results show that Cu+ and Cu2+ binded on HZSM-5-M show the highest activity and product selectivity for the desired β-hydroxysulfides compounds. PMID:29257075

And the Last Shall Be First: Heterochrony and Compensatory Marine Growth in Sea Trout (Salmo trutta)

PubMed Central

Marco-Rius, Francisco; Caballero, Pablo; Morán, Paloma; Garcia de Leaniz, Carlos

2012-01-01

Early juvenile growth is a good indicator of growth later in life in many species because larger than average juveniles tend to have a competitive advantage. However, for migratory species the relationship between juvenile and adult growth remains obscure. We used scale analysis to reconstruct growth trajectories of migratory sea trout (Salmo trutta) from six neighbouring populations, and compared the size individuals attained in freshwater (before migration) with their subsequent growth at sea (after migration). We also calculated the coefficient of variation (CV) to examine how much body size varied across populations and life stages. Specifically, we tested the hypothesis that the CV on body size would differ between freshwater and marine environment, perhaps reflecting different trade-offs during ontogeny. Neighbouring sea trout populations differed significantly in time spent at sea and in age-adjusted size of returning adults, but not on size of seaward migration, which was surprisingly uniform and may be indicative of strong selection pressures. The CV on body size decreased significantly over time and was highest during the first 8 months of life (when juvenile mortality is highest) and lowest during the marine phase. Size attained in freshwater was negatively related to growth during the first marine growing season, suggesting the existence of compensatory growth, whereby individuals that grow poorly in freshwater are able to catch up later at sea. Analysis of 61 datasets indicates that negative or no associations between pre- and post-migratory growth are common amongst migratory salmonids. We suggest that despite a widespread selective advantage of large body size in freshwater, freshwater growth is a poor predictor of final body size amongst migratory fish because selection may favour growth heterochrony during transitions to a novel environment, and marine compensatory growth may negate any initial size advantage acquired in freshwater. PMID:23049680

Application of silver nanofluid containing oleic acid surfactant in a thermosyphon economizer.

PubMed

Parametthanuwat, Thanya; Rittidech, Sampan; Pattiya, Adisak; Ding, Yulong; Witharana, Sanjeeva

2011-04-07

This article reports a recent study on the application of a two-phase closed thermosyphon (TPCT) in a thermosyphon for economizer (TPEC). The TPEC had three sections of equal size; the evaporator, the adiabatic section, and the condenser, of 250 mm × 250 mm × 250 mm (W × L × H). The TPCT was a steel tube of 12.7-mm ID. The filling ratios chosen to study were 30, 50, and 80% with respect to the evaporator length. The volumetric flow rates for the coolant (in the condenser) were 1, 2.5, and 5 l/min. Five working fluids investigated were: water, water-based silver nanofluid with silver concentration 0.5 w/v%, and the nanofluid (NF) mixed with 0.5, 1, and 1.5 w/v% of oleic acid (OA). The operating temperatures were 60, 70, and 80°C. Experimental data showed that the TPEC gave the highest heat flux of about 25 kW/m2 and the highest effectiveness of about 0.3 at a filling ratio of 50%, with the nanofluid containing 1 w/v% of OA. It was further found that the effectiveness of nanofluid and the OA containing nanofluids were superior in effectiveness over water in all experimental conditions came under this study. Moreover, the presence of OA had clearly contributed to raise the effectiveness of the nanofluid.

Application of silver nanofluid containing oleic acid surfactant in a thermosyphon economizer

PubMed Central

2011-01-01

This article reports a recent study on the application of a two-phase closed thermosyphon (TPCT) in a thermosyphon for economizer (TPEC). The TPEC had three sections of equal size; the evaporator, the adiabatic section, and the condenser, of 250 mm × 250 mm × 250 mm (W × L × H). The TPCT was a steel tube of 12.7-mm ID. The filling ratios chosen to study were 30, 50, and 80% with respect to the evaporator length. The volumetric flow rates for the coolant (in the condenser) were 1, 2.5, and 5 l/min. Five working fluids investigated were: water, water-based silver nanofluid with silver concentration 0.5 w/v%, and the nanofluid (NF) mixed with 0.5, 1, and 1.5 w/v% of oleic acid (OA). The operating temperatures were 60, 70, and 80°C. Experimental data showed that the TPEC gave the highest heat flux of about 25 kW/m2 and the highest effectiveness of about 0.3 at a filling ratio of 50%, with the nanofluid containing 1 w/v% of OA. It was further found that the effectiveness of nanofluid and the OA containing nanofluids were superior in effectiveness over water in all experimental conditions came under this study. Moreover, the presence of OA had clearly contributed to raise the effectiveness of the nanofluid. PMID:21711856

Tethered balloon-based particle number concentration, and size distribution vertical profiles within the lower troposphere of Shanghai

NASA Astrophysics Data System (ADS)

Zhang, Kun; Wang, Dongfang; Bian, Qinggen; Duan, Yusen; Zhao, Mengfei; Fei, Dongnian; Xiu, Guangli; Fu, Qingyan

2017-04-01

A tethered balloon-based measurement campaign of particle number concentration (PNC) and particle number size distribution (PNSD) in the size range of 15.7-661.2 nm was conducted within the lower troposphere of 1000 m in Shanghai, a Chinese megacity, during December of 2015. The meteorological conditions, PNC, and PNSD were synchronously measured at the ground-based station as well as by the tethered balloon. On ground level, the 88.2 nm particles were found to have the highest PNC. The Pearson correlation analysis based on the ground level data showed NO2 had a strong correlation with PNC. The synchronous measurement of PNC and PNSD at the ground station and on the tethered balloon showed that the 15.7-200 nm particles had higher PNC on ground level, but the PNC of 200-661.2 nm particles was higher at 400 m. One haze event (Dec 22nd-Dec 23rd) was selected for detailed discussion on the variation of vertical profiles of PNSD and PNC. The vertical distribution of characteristics of PNC and PNSD were observed and compared. Results indicated that the highest MaxDm (the diameter with the highest PNC) during those three launches all appeared at a high altitude, usually above 300 m. Compared to the clean days, the relatively bigger MaxDm at each height in the haze days also indicated regional transport of pollutants might contribute to more to that haze event.

The role of business size in assessing the uptake of health promoting workplace initiatives in Australia.

PubMed

Taylor, A W; Pilkington, R; Montgomerie, A; Feist, H

2016-04-21

Worksite health promotion (WHP) initiatives are increasingly seen as having potential for large-scale health gains. While health insurance premiums are directly linked to workplaces in the USA, other countries with universal health coverage, have less incentive to implement WHP programs. Size of the business is an important consideration with small worksites less likely to implement WHP programs. The aim of this study was to identify key intervention points and to provide policy makers with evidence for targeted interventions. The worksites (n = 218) of randomly selected, working participants, aged between 30 and 65 years, in two South Australian cohort studies were surveyed to assess the practices, beliefs, and attitudes regarding WHP. A survey was sent electronically or by mail to management within each business. Smaller businesses (<20 employees) had less current health promotion activies (mean 1.0) compared to medium size businesses (20-200 employees - mean 2.4) and large businesses (200+ employees - mean 2.9). Management in small businesses were less likely (31.0 %) to believe that health promotion belonged in the workplace (compared to 55.7 % of medium businesses and 73.9 % of large businesses) although half of small businesses did not know or were undecided (compared to 36.4 and 21.6 % of medium and large businesses). In total, 85.0 % of smaller businesses believed the health promotion activities currently employed in the worksite were effective (compared to 89.2 % of medium businesses and 83.1 % of large businesses). Time and funding were the most cited responses to the challenges to implementing health promoting strategies regardless of business size. Small businesses ranked morale and work/life balance the highest among a range of health promotion activities that were important for their workplace while work-related injury was the highest ranked consideration for large businesses. This study found that smaller workplaces had many barriers, beliefs and challenges regarding WHP. Often small businesses find health promotion activities a luxury and not a serious focus of their activities although this study found that once a health promoting strategy was employed, the perceived effectiveness of the activities were high for all business regardless of size. Tailored low-cost programs, tax incentives, re-orientation of work practices and management support are required so that the proportion of small businesses that have WHP initiatives is increased.

Effect of heat treatment On Microstructure of steel AISI 01 Tools

NASA Astrophysics Data System (ADS)

Dyanasari Sebayang, Melya; Yudo, Sesmaro Max; Silitonga, Charlie

2018-03-01

This study discusses the influence of quenching, normalizing, and annealing to changes in hardness, tensile, and microstructure of materials tool steel AISI 01 after the material undergo heat treatment process. This heat treatment process includes an initial warming of 600° C and a 5-minute detention time, followed by heating to an austenisation temperature of 850°C. After that a different cooling process, including annealing process, normalizing and quenching oil SAE 40. Tests performed include tensile, hard, and microstructure with shooting using SEM (Scanning Electron Microscope). This is done to see the effect of different heat treatment and cooling process. The result of this research is difference of tensile test value, hard, and micro structure from influence of difference of each process. The quenching process obtains the highest tensile and hard values followed by the normalizing process, annealing, and the lowest is in the starting material, this is because the initial material does not undergo heat treatment process. The resulting microstructure is pearlit and cementite, the difference seen from the shape and size of the grains. The larger the grain size, the greater the hardness.

Mercury and methylmercury in reservoirs in Indiana

USGS Publications Warehouse

Risch, Martin R.; Fredericksen, Amanda L.

2015-01-01

Methylmercury (reported as Hg) in fish-tissue samples collected for the State fish consumption advisory program was used to describe MeHg food-web accumulation and magnification in the reservoirs. The highest percentages of fish-tissue samples with Hg concentrations that exceeded the criterion of 0.30 milligram per kilogram for protection of human health were from Monroe Lake (38 percent) and Patoka Lake (33 percent). A review of the number and size of fish species caught from these two reservoirs resulted in two implications for fish consumption by humans. First, the highest numbers of fish harvested for potential human consumption were species more likely to have MeHg concentrations lower than the human-health criterion (crappie, bluegill, and catfish). Second, although largemouth bass were likely to have MeHg concentrations higher than the human-health criterion, they were caught and released more often than they were harvested. However, the average size largemouth bass (in both reservoirs) and above-average size walleye (in Monroe Lake) that were harvested for potential human consumption were likely to have MeHg concentrations higher than the human-health criterion.

The effect of surface grinding and sandblasting on flexural strength and reliability of Y-TZP zirconia ceramic.

PubMed

Kosmac, T; Oblak, C; Jevnikar, P; Funduk, N; Marion, L

1999-11-01

This study was conducted to evaluate the effect of grinding and sandblasting on the microstructure, biaxial flexural strength and reliability of two yttria stabilized tetragonal zirconia (Y-TZP) ceramics. Two Y-TZP powders were used to produce fine grained and coarse grained microstructures. Sixty discs from each material were randomly divided into six groups of ten. For each group, a different surface treatment was applied: dry grinding, wet grinding, sandblasting, dry grinding + sandblasting, sandblasting + dry grinding and a control group. Biaxial flexural strength was determined and data were analyzed using one-way ANOVA, followed by Tukey's HSD test (p < 0.05). In addition, Weibull statistics was used to analyze the variability of flexural strength. The relative amount of transformed monoclinic zirconia, corresponding transformed zone depth (TZD) and the mean critical defect size Ccr were calculated. There was no difference in mean strength between the as sintered fine and coarse grained Y-TZP. Significant differences (p < 0.05) were found between the control group and ground fine grained material for both wet and dry grinding. Sandblasting significantly increased the strength in fine and coarse grained materials. All surface treatment procedures reduced the Weibull modulus of Y-TZP. For both materials, the highest amount of the monoclinic phase and the largest TZD was found after sandblasting. Lower amounts of the monoclinic phase were obtained after both grinding procedures, where the highest mean critical defect size Ccr was also calculated. Our results indicate that sandblasting may provide a powerful technique for strengthening Y-TZP in clinical practice. In contrast, grinding may lead to substantial strength degradation and reduced reliability of prefabricated zirconia elements, therefore, sandblasting of ground surfaces is suggested.

Protection of skin with subcutaneous administration of 5% dextrose in water during superficial radiofrequency ablation in a rabbit model.

PubMed

Guo, Hui; Liu, Xia-Lei; Wang, Yu-Ling; Li, Jing-Yi; Lu, Wu-Zhu; Xian, Jian-Zhong; Zhang, Bai-Meng; Li, Jian

2014-06-01

This study was to evaluate the efficacy of subcutaneous administration of 5% dextrose in water (D5W), to prevent skin injury during radiofrequency (RF) ablation. Twenty-four rabbits were divided into three groups: a pre-injection group, a perfusion group, and a control group. Ablative zones were created in the superficial part of the thigh muscle for 6 min. A needle was placed subcutaneously for injection of D5W, and a thermal sensor was positioned nearby for real-time temperature monitoring. The sizes of the ablative zones were measured by contrast-enhanced ultrasonography, and severity of the observed skin injury were scored semi-quantitatively and compared. The highest temperature, the duration of the temperature above 50 °C, and the rise time of the post-procedure temperature were all highest in the control group (p < 0.001), while these values were lower in the perfusion group than those in the pre-injection group (p < 0.001). Post-procedure skin injury was most severe in the control group (p < 0.001). On post-procedure day 1, no significant difference was found between the skin injury of the pre-injection group and the perfusion group (p = 0.091), while the skin injury of the perfusion group was less severe than that of the pre-injection group on post-procedure day 14 (p = 0.004). No significant difference was found in the sizes of the ablative zones among the groups (p = 0.720). Subcutaneous perfusion with D5W is effective in protecting the skin against burns during RF ablation without compromising the effect of ablation.

Predicting higher selection in elite junior Australian Rules football: The influence of physical performance and anthropometric attributes.

PubMed

Robertson, Sam; Woods, Carl; Gastin, Paul

2015-09-01

To develop a physiological performance and anthropometric attribute model to predict Australian Football League draft selection. Cross-sectional observational. Data was obtained (n=4902) from three Under-18 Australian football competitions between 2010 and 2013. Players were allocated into one of the three groups, based on their highest level of selection in their final year of junior football (Australian Football League Drafted, n=292; National Championship, n=293; State-level club, n=4317). Physiological performance (vertical jumps, agility, speed and running endurance) and anthropometric (body mass and height) data were obtained. Hedge's effect sizes were calculated to assess the influence of selection-level and competition on these physical attributes, with logistic regression models constructed to discriminate Australian Football League Drafted and National Championship players. Rule induction analysis was undertaken to determine a set of rules for discriminating selection-level. Effect size comparisons revealed a range of small to moderate differences between State-level club players and both other groups for all attributes, with trivial to small differences between Australian Football League Drafted and National Championship players noted. Logistic regression models showed multistage fitness test, height and 20 m sprint time as the most important attributes in predicting Draft success. Rule induction analysis showed that players displaying multistage fitness test scores of >14.01 and/or 20 m sprint times of <2.99 s were most likely to be recruited. High levels of performance in aerobic and/or speed tests increase the likelihood of elite junior Australian football players being recruited to the highest level of the sport. Copyright © 2014 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

Effects of irrigation moisture regimes on yield and quality of paprika ( Capsicum annuum L)

NASA Astrophysics Data System (ADS)

Shongwe, Victor D.; Magongo, Bekani N.; Masarirambi, Michael T.; Manyatsi, Absalom M.

Although paprika ( Capsicum annuum L) is not widely grown in Swaziland it is becoming increasingly popular as a spice and food colourant. It is a crop that requires irrigation at specific stages of growth as this affects not only the yield but most importantly the quality of the crop. Yield of paprika has been found to increase with relative increase in moisture whereas the quality of fruits has not followed the same trend. The objective of this study was to find the effect of varying irrigation water regimes on the yield and quality of paprika at uniform fertiliser levels. The study was carried out in the 2006/2007 cropping season at the Luyengo campus of the University of Swaziland in a greenhouse. A randomised complete block design was used with four water treatments (0.40, 0.60, 0.80, and 1.00 × Field Capacity). Parameters measured included leaf number per plant, plant height, chlorophyll content, canopy size, leaf width, leaf length, stem girth, dry mass, fresh mass, fruit length, and brix content. There were significant ( P < 0.05) increases in leaf number, plant height, chlorophyll content, canopy size, fresh and dry mass tops and fruit length at the highest moisture level (1.00 × FC) followed by the second highest regime (0.80 × FC) whilst the lower water regimes resulted in lower increases in each of the parameters. Leaf area index did not differ significantly across all treatments. In increasing order the treatments 0.80 × FC and 1.00 × FC gave higher yields but in decreasing order lower brix and thus subsequent lower paprika quality. It is recommended that growers who are aiming for optimum yield and high quality of paprika may use the 0.8 × FC treatment when irrigating.

Efficacy of hormone therapy with and without methyltestosterone augmentation of venlafaxine in the treatment of postmenopausal depression: a double-blind controlled pilot study.

PubMed

Dias, Rodrigo S; Kerr-Corrêa, Florence; Moreno, Ricardo A; Trinca, Luzia A; Pontes, Anagloria; Halbe, Hans W; Gianfaldoni, Arlete; Dalben, Ivete S

2006-01-01

This study evaluated the augmentation of venlafaxine with hormone therapy in the treatment of postmenopausal depression. The hormones evaluated were estrogen (0.625 mg) in combination with medroxyprogesterone acetate (2.5 mg) and methyltestosterone (2.5 mg). Seventy-two menopausal women (mean age: 53.6 +/- 4.27 years) diagnosed with depression (Montgomery-Asberg Depression Rating Scale [MADRS] scores > or = 20) were treated with venlafaxine and one of the following hormone therapy combinations, in a double-blind regimen: estrogen + medroxyprogesterone + methyltestosterone (group 1, n = 20); estrogen + medroxyprogesterone acetate (group 2, n = 20); methyltestosterone only (group 3, n = 16); and no hormone therapy (group 4, n = 16). Study duration was 24 weeks. Primary efficacy outcome was remission according to the MADRS, whereas secondary efficacy measures included the Clinical Global Impression (CGI), Blatt-Kupperman Index, and Women's Health Questionnaire (WHQ). Forty-eight patients completed the study. All groups showed significant improvement from baseline. Group 3 demonstrated significant improvement on the MADRS compared with placebo (group 4) at weeks 20 (P = 0.048) and 24 (P = 0.030); effect size 8.04 (0.83; 15.26) (P = 0.029), but also had the highest dropout rate. Groups 1 and 3 had significant CGI improvement rates compared with placebo: 42.23% (P = 0.012) and 44.45% (P = 0.08), respectively. There were no differences in the WHQ or BKI scores among the groups. Methyltestosterone 2.5 mg had the highest effect size compared with placebo, but the high dropout rate prevented its efficacy from being determined. Estrogen plus medroxyprogesterone, combined with methyltestosterone or otherwise, demonstrated a trend toward increased efficacy of venlafaxine. Further larger-scale clinical trials are needed to elucidate the findings of this pilot study.

Photocurrent enhancement of SiNW-FETs by integrating protein-shelled CdSe quantum dots

NASA Astrophysics Data System (ADS)

Moh, Sang Hyun; Kulkarni, Atul; San, Boi Hoa; Lee, Jeong Hun; Kim, Doyoun; Park, Kwang Su; Lee, Min Ho; Kim, Taesung; Kim, Kyeong Kyu

2016-01-01

We proposed a new strategy to increase the photoresponsivity of silicon NW field-effect transistors (FETs) by integrating CdSe quantum dots (QDs) using protein shells (PSs). CdSe QDs were synthesized using ClpP, a bacterial protease, as protein shells to control the size and stability of QD and to facilitate the mounting of QDs on SiNWs. The photocurrent of SiNW-FETs in response to light at a wavelength of 480 nm was enhanced by a factor of 6.5 after integrating CdSe QDs because of the coupling of the optical properties of SiNWs and QDs. As a result, the photoresponsivity to 480 nm light reached up to 3.1 × 106, the highest value compared to other SiNW-based devices in the visible light range.We proposed a new strategy to increase the photoresponsivity of silicon NW field-effect transistors (FETs) by integrating CdSe quantum dots (QDs) using protein shells (PSs). CdSe QDs were synthesized using ClpP, a bacterial protease, as protein shells to control the size and stability of QD and to facilitate the mounting of QDs on SiNWs. The photocurrent of SiNW-FETs in response to light at a wavelength of 480 nm was enhanced by a factor of 6.5 after integrating CdSe QDs because of the coupling of the optical properties of SiNWs and QDs. As a result, the photoresponsivity to 480 nm light reached up to 3.1 × 106, the highest value compared to other SiNW-based devices in the visible light range. Electronic supplementary information (ESI) available: Materials and methods. See DOI: 10.1039/c5nr07901b

Decoupling the Effects of High Crystallinity and Surface Area on the Photocatalytic Overall Water Splitting over β-Ga2 O3 Nanoparticles by Chemical Vapor Synthesis.

PubMed

Lukic, Sasa; Menze, Jasper; Weide, Philipp; Busser, G Wilma; Winterer, Markus; Muhler, Martin

2017-09-11

Chemical vapor synthesis (CVS) is a unique method to prepare well-defined photocatalyst materials with both large specific surface area and a high degree of crystallinity. The obtained β-Ga 2 O 3 nanoparticles were optimized for photocatalysis by reductive photodeposition of the Rh/CrO x co-catalyst system. The influence of the degree of crystallinity and the specific surface area on photocatalytic aqueous methanol reforming and overall water splitting (OWS) was investigated by synthesizing β-Ga 2 O 3 samples in the temperature range from 1000 °C to 1500 °C. With increasing temperature, the specific surface area and the microstrain were found to decrease, whereas the degree of crystallinity and the crystallite size increased. Whereas the photocatalyst with the highest specific surface area showed the highest aqueous methanol reforming activity, the highest OWS activity was that for the sample with an optimum ratio between high degree of crystallinity and specific surface area. Thus, it was possible to show that the facile aqueous methanol reforming and the demanding OWS have different requirements for high photocatalytic activity. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Tungsten substituted molybdophosphoric acid loaded on various types of mesoporous silica SBA-15 for application of thorium ion adsorption

NASA Astrophysics Data System (ADS)

Aghayan, H.; Khanchi, A. R.; Yousefi, T.; Ghasemi, H.

2017-12-01

In this research, three type of mesoporous silica with different morphologies, namely fibers, spheres and platelets were synthesized and used as a support for immobilization of [H3PMo6W6O40].nH2O. The samples were then applied as an inorganic composite ion-exchanger for sorption of thorium from aqueous solution. Various techniques including ICP, XRD, BET, SEM and FT-IR methods were used to characterize of the products. The experiment results showed that the [H3PMo6W6O40].nH2O supported on the platelet mesoporous silica exhibited both the highest sorption capacity and fastest kinetics when compared with the fibers and spheres adsorbents. Our results show that the morphology of the mesoporous support, which can produce different channel lengths, pore size and surface area, has a serious effect on the sorption properties and influences: (1) the amount of loading of heteropoly acid in the support (2) the kinetic of the sorption process and (3) the maximum of adsorption capacity. The platelet morphology showed the shortest equilibrium time, the highest loading amount and the highest adsorption capacity therefore delivering the best performance among the three morphologies.

Effect of Process Variables on the Grain Size and Crystallographic Texture of Hot-Dip Galvanized Coatings

NASA Astrophysics Data System (ADS)

Kaboli, Shirin; McDermid, Joseph R.

2014-08-01

A galvanizing simulator was used to determine the effect of galvanizing bath antimony (Sb) content, substrate surface roughness, and cooling rate on the microstructural development of metallic zinc coatings. Substrate surface roughness was varied through the use of relatively rough hot-rolled and relatively smooth bright-rolled steels, cooling rates were varied from 0.1 to 10 K/s, and bulk bath Sb levels were varied from 0 to 0.1 wt pct. In general, it was found that increasing bath Sb content resulted in coatings with a larger grain size and strongly promoted the development of coatings with the close-packed {0002} basal plane parallel to the substrate surface. Increasing substrate surface roughness tended to decrease the coating grain size and promoted a more random coating crystallographic texture, except in the case of the highest Sb content bath (0.1 wt pct Sb), where substrate roughness had no significant effect on grain size except at higher cooling rates (10 K/s). Increased cooling rates tended to decrease the coating grain size and promote the {0002} basal orientation. Calculations showed that increasing the bath Sb content from 0 to 0.1 wt pct Sb increased the dendrite tip growth velocity from 0.06 to 0.11 cm/s by decreasing the solid-liquid interface surface energy from 0.77 to 0.45 J/m2. Increased dendrite tip velocity only partially explains the formation of larger zinc grains at higher Sb levels. It was also found that the classic nucleation theory cannot completely explain the present experimental observations, particularly the effect of increasing the bath Sb, where the classical theory predicts increased nucleation and a finer grain size. In this case, the "poisoning" theory of nucleation sites by segregated Sb may provide a partial explanation. However, any analysis is greatly hampered by the lack of fundamental thermodynamic information such as partition coefficients and surface energies and by a lack of fundamental structural studies. Overall, it was concluded that the fundamental mechanisms behind the microstructural development of solidified metallic zinc coatings have yet to be completely elucidated and require further investigation.

Effect of Peptides' Binding on the Antimicrobial Activity and Biocompatibility of Protein-Based Substrates

NASA Astrophysics Data System (ADS)

Kaisersberger Vincek, Maja

This work reveals the effect of coupling approach (chemical by using carbodiimide chemistry and grafting-to vs. grafting-from synthesis routes, and enzymatic by using transglutaminase) of a hydrophilic epsilon-poly-L-lysine (epsilonPL) and an amphiphilic oligo-acyl-lysyl (OAK) derivative (K-7alpha 12-OH) to wool fibers and gelatine (GEL) macromolecules, respectively, and substrates antibacterial activity against Gram-negative E. coli and Gram-positive S. aureus bacteria after 1-24 h of exposure, as well as their cytotoxicity. Different spectroscopic (ultraviolet-visible, infrared, fluorescence and electron paramagnetic resonance) and separation techniques (size-exclusion chromatography and capillary zone electrophoresis) as well as zeta potential and potentiometric titration analysis, were performed to confirm the covalent coupling of epsilonPL/OAK, and to determine the amount and orientation of its immobilisation. The highest and kinetically the fastest level of bacterial reduction was achieved with wool/GEL functionalised with epsilonPL/OAK by chemical grafting-to approach. This effect correlated with both the highest grafting yield and conformationally the highly-flexible (brush-like) orientation linkage of epsilonPL/OAK, implicating on the highest amount of accessible amino groups interacting with bacterial membrane. However, OAK's amphipathic structure, the cationic charge and the hydrophobic moieties, resulted to relatively high reduction of S. aureus for grafting-from and the enzymatic coupling approaches using OAK-functionalised GEL. The epsilonPL/OAK-functionalised GEL did not induce toxicity in human osteoblast cells, even at 25-fold higher concentration than bacterial minimum inhibitory (MIC) concentration of epsilonPL/OAK, supporting their potential usage in biomedical applications. It was also shown that non-ionic surfactant adsorbs strongly onto the wool surface during the process of washing, thereby blocking the functional sites of immobilized epsilonPL and decreases its antibacterial efficiency.

Harem: Hardwood lumber remanufacturing program for maxmizing value based on size, grade and current market prices

Treesearch

C.J. Schwehm; P. Klinkhachorn; Charles W. McMillin; Henry A. Huber

1990-01-01

This paper describes an expert system computer program which will determine the optimum way to edge and trim a hardwood board so as to yield the highest dollar value based on the grade, size of each board, and current market prices. The program uses the Automated Hardwood Lumber Grading Program written by Klinkhachorn, et al. for determining the grade of each board...

Fight tactics in wood ants: individuals in smaller groups fight harder but die faster

PubMed Central

Batchelor, Tim P.; Briffa, Mark

2011-01-01

When social animals engage in inter-group contests, the outcome is determined by group sizes and individual masses, which together determine group resource-holding potential (‘group RHP’). Individuals that perceive themselves as being in a group with high RHP may receive a motivational increase and increase their aggression levels. Alternatively, individuals in lower RHP groups may increase their aggression levels in an attempt to overcome the RHP deficit. We investigate how ‘group RHP’ influences agonistic tactics in red wood ants Formica rufa. Larger groups had higher total agonistic indices, but per capita agonistic indices were highest in the smallest groups, indicating that individuals in smaller groups fought harder. Agonistic indices were influenced by relative mean mass, focal group size, opponent group size and opponent group agonistic index. Focal group attrition rates decreased as focal group relative agonistic indices increased and there was a strong negative influence of relative mean mass. The highest focal attrition rates were received when opponent groups were numerically large and composed of large individuals. Thus, fight tactics in F. rufa seem to vary with both aspects of group RHP, group size and the individual attributes of group members, indicating that information on these are available to fighting ants. PMID:21389029

In vitro cell imaging using multifunctional small sized KGdF4:Yb3+,Er3+ upconverting nanoparticles synthesized by a one-pot solvothermal process

NASA Astrophysics Data System (ADS)

Wong, Hon-Tung; Tsang, Ming-Kiu; Chan, Chi-Fai; Wong, Ka-Leung; Fei, Bin; Hao, Jianhua

2013-03-01

Multifunctional KGdF4:18%Yb3+,2%Er3+ nanoparticles with upconversion fluorescence and paramagnetism are synthesized. The average sizes of the nanoparticles capped with branched polyethyleneimine (PEI) and 6-aminocaproic acid (6AA) are ~14 and ~13 nm, respectively. Our KGdF4 host does not exhibit any phase change with the decrease of particle size, which can prevent the detrimental significant decrease in upconversion luminescence caused by this effect observed in the well-known NaYF4 host. The branched PEI and 6AA capping ligands endow our nanoparticles with water-dispersibility and biocompatibility, which can favor internalization of our nanoparticles into the cytoplasm of HeLa cells and relatively high cell viability. The strong upconversion luminescence detected at the cytoplasm of HeLa cells incubated with the branched PEI-capped nanoparticles is probably attributed to the reported high efficiency of cellular uptake. The magnetic mass susceptibility of our nanoparticle is 8.62 × 10-5 emu g-1 Oe-1. This is the highest value ever reported in trivalent rare-earth ion-doped KGdF4 nanoparticles of small size (<=14 nm), and is very close to that of nanoparticles used as T1 contrast agents in magnetic resonance imaging. These suggest the potential of our KGdF4:Yb3+,Er3+ nanoparticles as small-sized multifunctional bioprobes.

Sex determination by three-dimensional geometric morphometrics of craniofacial form.

PubMed

Chovalopoulou, Maria-Eleni; Valakos, Efstratios D; Manolis, Sotiris K

The purpose of the present study is to define which regions of the cranium, the upper-face, the orbits and the nasal are the most sexually dimorphic, by using three-dimensional geometric morphometric methods, and investigate the effectiveness of this method in determining sex from the shape of these regions. The study sample consisted of 176 crania of known sex (94 males, 82 females) belonging to individuals who lived in Greece during the 20(th) century. The three-dimensional co-ordinates of 31 ecto-cranial landmarks were digitized using a MicroScribe 3DX contact digitizer. Goodall's F-test was performed in order to compare statistical differences in shape between males and females. Generalized Procrustes Analysis (GPA) was used to obtain size and shape variables for statistical analysis. Shape, Size and Form analyses were carried out by logistic regression and discriminant function analysis. The results indicate that there are shape differences between the sexes in the upper-face and the orbits. The highest shape classification rate was obtained from the upper-face region. The centroid size of the caraniofacial and the orbital regions was smaller in females than males. Moreover, it was found that size is significant for sexual dimorphism in the upper-face region. As anticipated, the classification accuracy improves when both size and shape are combined. The findings presented here constitute a firm basis upon which further research can be conducted.

Prospective study of vaginal dilator use adherence and efficacy following radiotherapy

PubMed Central

Law, Ethel; Kelvin, Joanne F.; Thom, Bridgette; Riedel, Elyn; Tom, Ashlyn; Carter, Jeanne; Alektiar, Kaled; Goodman, Karyn A.

2016-01-01

Background and purpose Vaginal stenosis (VS) after pelvic radiotherapy can impair long-term quality of life. We prospectively assessed adherence and efficacy of VD use as the primary and secondary objectives, respectively. Material and methods Women with gastrointestinal (n=63) and gynecologic (n=46) cancers self-reported use and VD size in monthly diaries for 12 months after radiotherapy. Adherence was measured as actual VD use out of recommended times over 12 months (3×/week × 52 weeks = 156). Results Among 109 participants, aged 28–81 years (median, 58 years), mean percent adherence over 12 months was 42% (95% confidence interval [CI], 36%–48%). Adherence was highest in the first quarter (56%), but fell to 25% by the fourth. Disease type, treatment sequence, and chemotherapy were predictors of adherence (all P<.05). Eighty-two percent maintained pre-RT VD size at 12 months; of 49% with decrease in VD size at 1 month post-RT, 71% returned to pre-RT VD size at 12 months. Disease type, younger age, and increased adherence at 6 months were associated with maintaining or returning to pre-RT size at 12 months (all P≤.05). Conclusions VD use is effective in minimizing VS, but adherence at 12 months was poor. Studies evaluating methods of improving adherence and determining the optimal frequency and duration of use are needed. PMID:26164775

Effects of Nanoparticle Size on Multilayer Formation and Kinetics of Tethered Enzymes.

PubMed

Lata, James P; Gao, Lizeng; Mukai, Chinatsu; Cohen, Roy; Nelson, Jacquelyn L; Anguish, Lynne; Coonrod, Scott; Travis, Alexander J

2015-09-16

Despite numerous applications, we lack fundamental understanding of how variables such as nanoparticle (NP) size influence the activity of tethered enzymes. Previously, we showed that biomimetic oriented immobilization yielded higher specific activities versus nonoriented adsorption or carboxyl-amine binding. Here, we standardize NP attachment strategy (oriented immobilization via hexahistidine tags) and composition (Ni-NTA coated gold NPs), to test the impact of NP size (⌀5, 10, 20, and 50 nm) on multilayer formation, activity, and kinetic parameters (kcat, KM, kcat/KM) of enzymes representing three different classes: glucose-6-phosphate isomerase (GPI), an isomerase; Glyceraldehyde-3-phosphate dehydrogenase S (GAPDHS), an oxidoreductase; and pyruvate kinase (PK), a transferase. Contrary to other reports, we observed no trend in kinetic parameters for individual enzymes when found in monolayers (<100% enzyme coverage), suggesting an advantage for oriented immobilization versus other attachment strategies. Saturating the NPs to maximize activity per NP resulted in enzyme multilayer formation. Under these conditions, total activity per NP increased with increasing NP size. Conversely, specific activity for all three enzymes was highest when tethered to the smallest NPs, retaining a remarkable 73-94% of the activity of free/untethered enzymes. Multilayer formations caused a clear trend of kcat decreasing with increasing NP size, yet negligible change in KM. Understanding the fundamental relationships between NP size and tethered enzyme activity enables optimized design of various applications, maximizing activity per NP or activity per enzyme molecule.

[Distribution of atmospheric ultrafine particles during haze weather in Hangzhou].

PubMed

Chen, Qiu-Fang; Sun, Zai; Xie, Xiao-Fang

2014-08-01

Atmospheric ultrafine particles (UFPs) were monitored with fast mobility particle sizer (FMPS) in continuous haze weather and the haze fading process during December 6 to 11, 2013 in Hangzhou. Particle concentration and size distribution were studied associated with meteorological factors. The results showed that number concentrations were the highest at night and began to reduce in the morning. There was a small peak at 8 o'clock in the morning and 18 o'clock in the afternoon. It showed an obvious peak traffic source, which indicated that traffic emissions played a great role in the atmospheric pollution. During haze weather, the highest number concentration of UFPs reached 8 x 10(4) cm(-3). Particle size spectrum distribution was bimodal, the peak particle sizes were 15 nm and 100 nm respectively. Majority of UFPs were Aitken mode and Accumulation mode and the size of most particles concentrated near 100 nm. Average CMD(count medium diameter) was 85.89 nm. During haze fading process, number concentration and particles with size around 100 nm began to reduce and peak size shifted to small size. Nuclear modal particles increased and were more than accumulation mode. Average CMD was 58.64 nm. Meteorological factors such as the visibility and wind were negatively correlated with the particle number concentration. Correlation coefficient R were -0.225 and - 0.229. The humidity was correlated with number concentration. Correlation coefficient R was 0.271. The atmosphere was stable in winter and the level temperature had small correlation with number concentration. Therefore, study on distribution of atmospheric ultrafine particles during haze weather had the significance on the formation mechanism and control of haze weather.

Association of Overweight with Food Portion Size among Adults of São Paulo - Brazil.

PubMed

Pereira, Jaqueline Lopes; Mendes, Aline; Crispim, Sandra Patricia; Marchioni, Dirce Maria; Fisberg, Regina Mara

2016-01-01

Although studies show that portion size affects energy intake, few have demonstrated a link between portion size and weight status, especially in free-living populations. The objective of the present study was to assess the relationship between food portion sizes and overweight in a representative population of adults of São Paulo, Brazil. Cross-sectional population-based study with 1005 adults from São Paulo, Brazil. Dietary data were obtained from two 24-hour recalls. Reported foods were classified into groups and energy contribution, prevalence of consumers and portion sizes were calculated. Individuals were classified according to BMI in with and without overweight. Logistic regression models were used to evaluate the association between food portion sizes and being overweight. The most consumed food groups were: beans, breads/rolls, coffee/tea, milk, rice, and sugar. Rice, red meat, breads/rolls, and white meat were the groups with the highest percentage of contribution to total energy intake. Butter/margarine, toasts/biscuits, sugar, and cakes were the groups with the highest energy density. After adjustment for confounding variables, overweight was associated with larger portions of pizza (OR = 1.052; p = 0.048), red meat (OR = 1.025; p = 0.043), rice (OR = 1.033; p<0.001), salted snacks (OR = 1.078; p = 0.022), and soft drinks (OR = 1.016; p = 0.007). Larger portions of few food groups with different energy densities were associated with being overweight, suggesting that overweight may be related to the consumption of larger portion sizes of a series of food groups, not a food group alone. Additionally, we highlight the importance of considering underreporting as a confounding factor in these associations.

Interactive video gaming compared with health education in older adults with mild cognitive impairment: a feasibility study.

PubMed

Hughes, Tiffany F; Flatt, Jason D; Fu, Bo; Butters, Meryl A; Chang, Chung-Chou H; Ganguli, Mary

2014-09-01

We evaluated the feasibility of a trial of Wii interactive video gaming, and its potential efficacy at improving cognitive functioning compared with health education, in a community sample of older adults with neuropsychologically defined mild cognitive impairment. Twenty older adults were equally randomized to either group-based interactive video gaming or health education for 90 min each week for 24 weeks. Although the primary outcomes were related to study feasibility, we also explored the effect of the intervention on neuropsychological performance and other secondary outcomes. All 20 participants completed the intervention, and 18 attended at least 80% of the sessions. The majority (80%) of participants were "very much" satisfied with the intervention. Bowling was enjoyed by the most participants and was also rated the highest among the games for mental, social, and physical stimulation. We observed medium effect sizes for cognitive and physical functioning in favor of the interactive video gaming condition, but these effects were not statistically significant in this small sample. Interactive video gaming is feasible for older adults with mild cognitive impairment, and medium effect sizes in favor of the Wii group warrant a larger efficacy trial. Copyright © 2014 John Wiley & Sons, Ltd.

Effects of various cavity designs on the performance of a CO2 TEA laser with an unstable resonator

NASA Technical Reports Server (NTRS)

Zhao, Yanzeng; Post, Madison J.; Lawrence, T. R.

1992-01-01

Unstable resonator modeling has been carried out for an injection-seeded CO2 transversely excited atmosphere (TEA) laser in the NOAA/ERL/Wave Propagation Laboratory (WPL) Doppler lidar to examine the effects of various cavity designs on the quality of the output beam. The results show the effects of an injection pinhole, electrode spacing, mirror tilt, and radial reflectivity function of the output coupler. The electrode spacing in this laser has negligible effect. The injection pinhole, however, produces complicated structures in the output patterns. If the pinhole is removed, the output pattern is much smoother, and the frequency jitter is smaller. Misalignment sensitivity is very closely related to the radial reflectivity function. The superparabolic function provides the highest coupling efficiency, largest beam size, and good collimation, but produces a slightly higher misalignment sensitivity compared with a parabolic function. The Gaussian function provides the lowest misalignment sensitivity, but it produces the smallest beam size and the largest beam divergence. Also, the coupling coefficient is 50 percent lower than the optimum value. Methods for using a flat diffraction grating in unstable resonators are also investigated. The best way is to use a flat grating/positive lens combination to replace the back concave mirror.

Effect of spot size and fluence on Q-switched alexandrite laser treatment for pigmentation in Asians: a randomized, double-blinded, split-face comparative trial.

PubMed

Wang, Chia-Chen; Chen, Chih-Kang

2012-10-01

Q-switched laser treatment for pigment disorders commonly leads to postinflammatory hyperpigmentation (PIH) in Asians. To evaluate the effect of spot size and fluence on Q-switched alexandrite laser (QSAL) treatment for pigmentation in Asians. Ten patients with freckles, 18 with lentigines, and 8 with acquired bilateral nevus of Ota-like macules (ABNOM) received 1 session of QSAL treatment for a 3-mm spot on one cheek and a 4-mm spot on the other cheek. The lowest fluences to achieve a visible biologic effect were chosen. The patients with freckles experienced the highest improvement rate (83-84%), followed by those with lentigines (52%) and ABNOM (35%). Similar efficacy was observed for both cheeks (p > 0.05). PIH developed in 10% (1/10), 44% (8/18), and 75% (6/8) of the patients with freckles, lentigines, and ABNOM, respectively. The severity of PIH was lower in the 4-mm spot with a lower fluence than in the 3-mm spot with a higher fluence in patients with lentigines (p = 0.03), but not in those with freckles or ABNOM. Using a larger spot to achieve the same biologic effect at a lower fluence is associated with equal efficacy and less-severe PIH in patients with lentigines.

Reduced transpiration response to precipitation pulses precedes mortality in a piñon-juniper woodland subject to prolonged drought.

PubMed

Plaut, Jennifer A; Wadsworth, W Duncan; Pangle, Robert; Yepez, Enrico A; McDowell, Nate G; Pockman, William T

2013-10-01

Global climate change is predicted to alter the intensity and duration of droughts, but the effects of changing precipitation patterns on vegetation mortality are difficult to predict. Our objective was to determine whether prolonged drought or above-average precipitation altered the capacity to respond to the individual precipitation pulses that drive productivity and survival. We analyzed 5 yr of data from a rainfall manipulation experiment in piñon-juniper (Pinus edulis-Juniperus monosperma) woodland using mixed effects models of transpiration response to event size, antecedent soil moisture, and post-event vapor pressure deficit. Replicated treatments included irrigation, drought, ambient control and infrastructure control. Mortality was highest under drought, and the reduced post-pulse transpiration in the droughted trees that died was attributable to treatment effects beyond drier antecedent conditions and reduced event size. In particular, trees that died were nearly unresponsive to antecedent shallow soil moisture, suggesting reduced shallow absorbing root area. Irrigated trees showed an enhanced response to precipitation pulses. Prolonged drought initiates a downward spiral whereby trees are increasingly unable to utilize pulsed soil moisture. Thus, the additive effects of future, more frequent droughts may increase drought-related mortality. © 2013 The Authors. New Phytologist © 2013 New Phytologist Trust.

Kidney Stones in Children and Teens

MedlinePlus

... Issues Listen Español Text Size Email Print Share Kidney Stones in Children and Teens Page Content Article ... teen girls having the highest incidence. Types of Kidney Stones There are many different types of kidney ...

Mediterranean dryland Mosaic: The effect of scale on core area metrics

NASA Astrophysics Data System (ADS)

Alhamad, Mohammad Noor; Alrababah, Mohammad

2014-05-01

Quantifying landscape spatial pattern is essential to understanding the relationship between landscape structure and ecological functions and process. Many landscape metrics have been developed to quantify spatial heterogeneity. Landscape metrics have been employed to measure the impact of humans on landscapes. We examined the response of four core areas metrics to a large range of grain sizes in Mediterranean dryland landscapes. The investigated metrics were (1) mean core area (CORE-MN), (2) area weighted mean core area (CORE-AM) , (3) total core area (TCA) and (4) core area percentage of landscape (CPLAND) within six land use types (urban, agriculture, olive orchids, forestry, shrubland and rangeland). Agriculture areas showed the highest value for minimum TCA (2779.4 ha) within the tested grain sizes, followed by rangeland (1778.3 ha) and Forest (1488.5 ha). On the other hand, shrubland showed the lowest TCA (8.0 ha). The minimum CPLAND values were ranged from 0.002 for shrubland to 0.682 for agriculture land use. The maximum CORE-MN among the tested land use type at all levels of grain sizes was exhibited by agriculture land use type (519.759 ha). The core area metrics showed three types of behavior in response to changing grain size in all landuse types. CORE-MN showed predictable relationship, best explained by non-linear responses to changing grain size (R2=0.99). Both TCA and CPLAND exhibited domain of scale effect in response to changing grain size. The threshold behavior for TCA and CPLAND was at the 4 x 4 grain size (about 1.3 ha). However, CORE-AM exhibited erratic behavior. The unique domain of scale-like behavior may be attributed to the unique characteristics of dryland Mediterranean landscapes; where both natural processes and ancient human activities play a great role in shaping the apparent pattern of the landscape

Comparison of non-toxic methods for creating beta-carotene encapsulated in PMMA nanoparticles

NASA Astrophysics Data System (ADS)

Dobrzanski, Christopher D.

Nano/microcapsules are becoming more prevalent in various industries such as drug delivery, cosmetics, etc. Current methods of particle formation often use toxic or carcinogenic/mutagenic/reprotoxic (CMR) chemicals. This study intends to improve upon existing methods of particle formation and compare their effectiveness in terms of entrapment efficiency, mean particle size, and yield utilizing only non-toxic chemicals. In this study, the solvent evaporation (SE), spontaneous emulsification, and spontaneous emulsion solvent diffusion (SESD) methods were compared in systems containing green solvents ethyl acetate, dimethyl carbonate or acetone. PMMA particles containing encapsulated beta carotene, an ultraviolet sensitive substance, were synthesized. It was desired to produce particles with minimum mean size and maximum yield and entrapment of beta carotene. The mass of the water phase, the mass of the polymer and the pumping or blending rate were varied for each synthesis method. The smallest particle sizes for SE and SESD both were obtained from the middle water phase sizes, 200 g and 100 g respectively. The particles obtained from the larger water phase in SESD were much bigger, about 5 microns in diameter, even larger than the ones obtained from SE. When varying the mass of PMMA used in each synthesis method, as expected, more PMMA led to larger particles. Increasing the blending rate in SE from 6,500 to 13,500 rpm had a minimal effect on average particle size, but the higher shear resulted in highly polydisperse particles (PDI = 0.87). By decreasing the pump rate in SESD, particles became smaller and had lower entrapment efficiency. The entrapment efficiencies of the particles were generally higher for the larger particles within a mode. Therefore, we found that minimizing the particle size while maximizing entrapment were somewhat contradictory goals. The solvent evaporation method was very consistent in terms of the values of mean particle size, yield, and entrapment efficiency. Comparing the synthesis methods, the smallest particles with the highest yield and entrapment efficiency were generated by the spontaneous emulsification method.

Effect of Matrix Size on the Image Quality of Ultra-high-resolution CT of the Lung: Comparison of 512 × 512, 1024 × 1024, and 2048 × 2048.

PubMed

Hata, Akinori; Yanagawa, Masahiro; Honda, Osamu; Kikuchi, Noriko; Miyata, Tomo; Tsukagoshi, Shinsuke; Uranishi, Ayumi; Tomiyama, Noriyuki

2018-01-16

This study aimed to assess the effect of matrix size on the spatial resolution and image quality of ultra-high-resolution computed tomography (U-HRCT). Slit phantoms and 11 cadaveric lungs were scanned on U-HRCT. Slit phantom scans were reconstructed using a 20-mm field of view (FOV) with 1024 matrix size and a 320-mm FOV with 512, 1024, and 2048 matrix sizes. Cadaveric lung scans were reconstructed using 512, 1024, and 2048 matrix sizes. Three observers subjectively scored the images on a three-point scale (1 = worst, 3 = best), in terms of overall image quality, noise, streak artifact, vessel, bronchi, and image findings. The median score of the three observers was evaluated by Wilcoxon signed-rank test with Bonferroni correction. Noise was measured quantitatively and evaluated with the Tukey test. A P value of <.05 was considered significant. The maximum spatial resolution was 0.14 mm; among the 320-mm FOV images, the 2048 matrix had the highest resolution and was significantly better than the 1024 matrix in terms of overall quality, solid nodule, ground-glass opacity, emphysema, intralobular reticulation, honeycombing, and clarity of vessels (P < .05). Both the 2048 and 1024 matrices performed significantly better than the 512 matrix (P < .001), except for noise and streak artifact. The visual and quantitative noise decreased significantly in the order of 512, 1024, and 2048 (P < .001). In U-HRCT scans, a large matrix size maintained the spatial resolution and improved the image quality and assessment of lung diseases, despite an increase in image noise, when compared to a 512 matrix size. Copyright © 2018 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.

Size matters at deep-sea hydrothermal vents: different diversity and habitat fidelity patterns of meio- and macrofauna

PubMed Central

Gollner, Sabine; Govenar, Breea; Fisher, Charles R.; Bright, Monika

2015-01-01

Species with markedly different sizes interact when sharing the same habitat. Unravelling mechanisms that control diversity thus requires consideration of a range of size classes. We compared patterns of diversity and community structure for meio- and macrofaunal communities sampled along a gradient of environmental stress at deep-sea hydrothermal vents on the East Pacific Rise (9° 50′ N) and neighboring basalt habitats. Both meio- and macrofaunal species richnesses were lowest in the high-stress vent habitat, but macrofaunal richness was highest among intermediate-stress vent habitats. Meiofaunal species richness was negatively correlated with stress, and highest on the basalt. In these deep-sea basalt habitats surrounding hydrothermal vents, meiofaunal species richness was consistently higher than that of macrofauna. Consideration of the physiological capabilities and life history traits of different-sized animals suggests that different patterns of diversity may be caused by different capabilities to deal with environmental stress in the 2 size classes. In contrast to meiofauna, adaptations of macrofauna may have evolved to allow them to maintain their physiological homeostasis in a variety of hydrothermal vent habitats and exploit this food-rich deep-sea environment in high abundances. The habitat fidelity patterns also differed: macrofaunal species occurred primarily at vents and were generally restricted to this habitat, but meiofaunal species were distributed more evenly across proximate and distant basalt habitats and were thus not restricted to vent habitats. Over evolutionary time scales these contrasting patterns are likely driven by distinct reproduction strategies and food demands inherent to fauna of different sizes. PMID:26166922

Investigation of Carbide Precipitation Process and Chromium Depletion during Thermal Treatment of Alloy 690

NASA Astrophysics Data System (ADS)

Jiao, S. Y.; Zhang, M. C.; Zheng, L.; Dong, J. X.

2010-01-01

For the purpose of studying the effect of heat treatment on carbide morphology and chromium concentration distribution, which are critical to the resistance of alloy 690 to stress corrosion cracking (SCC), a series of thermal treatments was performed. A model taking into account the intercorrelated dynamic process between the carbide precipitation and chemical diffusion of the chromium atom from matrix to grain boundary (GB) was constructed on the basis of classical nucleation theory, Kolmogorov-Johnson-Mehl-Avrami law, and diffusion theory. The validity of this model was evaluated by comparing the simulated results of the carbide average size and chromium concentration near the GB with the corresponding measured results. A discontinuous factor was introduced based on the relation linking the interdistance between the carbides and the carbide average size; thus, the carbide morphology and chromium concentration could be predicted by this model. According to the results of the experiments and simulations, a carbide discontinuous factor smaller than 2.2 together with the chromium concentration at the GB higher than a critical value (21 wt pct) were essential for the corrosion resistance ability of the alloy, and then some proper heat-treatment conditions were obtained through predicting the value of the two variables. In addition, the effects of the grain size and composition variation on the carbide discontinuous factor and chromium concentration profile were simulated. The results indicated that an intermediate grain size of approximately 31.8 to ~63.5 μm was beneficial for effectively improving the resistance of the alloy to SCC. Simultaneously, the carbon content should be adjusted near 0.02 pct, and the chromium content should be the highest possible in its chemical composition scale.

The Population Structure of Glossina palpalis gambiensis from Island and Continental Locations in Coastal Guinea

PubMed Central

Solano, Philippe; Ravel, Sophie; Bouyer, Jeremy; Camara, Mamadou; Kagbadouno, Moise S.; Dyer, Naomi; Gardes, Laetitia; Herault, Damien; Donnelly, Martin J.; De Meeûs, Thierry

2009-01-01

Background We undertook a population genetics analysis of the tsetse fly Glossina palpalis gambiensis, a major vector of sleeping sickness in West Africa, using microsatellite and mitochondrial DNA markers. Our aims were to estimate effective population size and the degree of isolation between coastal sites on the mainland of Guinea and Loos Islands. The sampling locations encompassed Dubréka, the area with the highest Human African Trypanosomosis (HAT) prevalence in West Africa, mangrove and savannah sites on the mainland, and two islands, Fotoba and Kassa, within the Loos archipelago. These data are discussed with respect to the feasibility and sustainability of control strategies in those sites currently experiencing, or at risk of, sleeping sickness. Principal Findings We found very low migration rates between sites except between those sampled around the Dubréka area that seems to contain a widely dispersed and panmictic population. In the Kassa island samples, various effective population size estimates all converged on surprisingly small values (10

Physicochemical investigations of biogenic chitosan-silver nanocomposite as antimicrobial and anticancer agent.

PubMed

Arjunan, Nithya; Kumari, Henry Linda Jeeva; Singaravelu, Chandra Mohan; Kandasamy, Ruckmani; Kandasamy, Jothivenkatachalam

2016-11-01

Chitosan (CS), a seaweed polysaccharide is a natural macromolecule which is widely being used in medical applications because of its distinctive antimicrobial and anticancer properties. Silver, a noble metal, is also receiving wide attention for its potential usage in antimicrobial and anticancer therapeutics. In this study, an effective way of reduction of silver using chitosan at varying reaction temperatures and an optimised concentration of silver were performed. The optical, structural, spectral, morphological and elemental studies of the biosynthesized chitosan-silver (CS-Ag) nanocomposites were characterized by several techniques. The synthesized CS-Ag nanocomposites exhibit particle size around 20nm and were further exploited for potent biological applications in nanomedicine due to their nanometric sizes and biocompatibility of chitosan. The antimicrobial activity of the biosynthesized CS-Ag nanocomposites exhibits zone of inhibition ranged between 09.666±0.577 and 19.000±1.000 (mm). The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were from 8 to 128μgmL -1 and 16 to 256μgmL -1 respectively, with the highest antimicrobial activity shown against Gram-negative Salmonella sp. The synergistic effect of chitosan and silver as a composite in nanometric size revealed significant IC 50 value of 29.35μgmL -1 and a maximum of 95.56% inhibition at 100μgmL -1 against A549 lung cancer cell line, resulting in potent anticancer effect. Copyright © 2016 Elsevier B.V. All rights reserved.

Distribution, bioavailability, and leachability of heavy metals in soil particle size fractions of urban soils (northeastern China).

PubMed

Yutong, Zong; Qing, Xiao; Shenggao, Lu

2016-07-01

This study examines the distribution, mobility, and potential environmental risks of heavy metals in various particle size fractions of urban soils. Representative urban topsoils (ten) collected from Anshan, Liaoning (northeastern China), were separated into six particle size fractions and their heavy metal contents (Cr, Cu, Cd, Pb, and Zn) were determined. The bioaccessibility and leachability of heavy metals in particle size fractions were evaluated using the toxicity characteristic leaching procedure (TCLP) and ethylenediaminetetraacetic acid (EDTA) extraction, respectively. The results indicated that the contents of five heavy metals (Cd, Cr, Cu, Pb and Zn) in the size fractions increased with the decrease of particle size. The clay fraction of <2 μm had the highest content of heavy metals, indicating that the clay fraction was polluted by heavy metals more seriously than the other size fractions in urban topsoils. Cr also concentrated in the coarse fraction of 2000-1000 μm, indicating a lithogenic contribution. However, the dominant size fraction responsible for heavy metal accumulation appeared to belong to particle fraction of 50-2 μm. The lowest distribution factors (DFs) of heavy metals were recorded in the 2000- to 1000-μm size fraction, while the highest in the clay fraction. The DFs of heavy metals in the clay fraction followed Zn (3.22) > Cu (2.84) > Pb (2.61) > Cr (2.19) > Cd (2.05). The enrichment factor suggested that the enrichment degree of heavy metal increased with the decrease of the particle size, especially for Cd and Zn. The TCLP- and EDTA-extractable concentrations of heavy metals in the clay fraction were relatively higher than those in coarse particles. Cd bioavailability was higher in the clay fraction than in other fractions or whole soils. In contrast, Cr exhibits similar bioaccessibilities in the six size fractions of soils. The results suggested that fine particles were the main sources of potentially toxic metals in urban soils. The variation of heavy metals in various size fractions should be taken into account in environment assessments.

Seasonal and photoperiodic effects on lipid droplet size and lipid peroxidation in the brown adipose tissue of bank voles (Myodes glareolus).

PubMed

Bonda-Ostaszewska, Elżbieta; Włostowski, Tadeusz; Krasowska, Alicja; Kozłowski, Paweł

2012-10-01

Seasonal changes in lipid droplet size and lipid peroxidation in the brown adipose tissue (BAT) of wild bank voles were examined. In addition, a role of photoperiod in these changes was studied; bank voles were held from the birth under long photoperiod (LP) for 12 weeks, and then half of them was transferred to short photoperiod (SP) for 6 weeks and another one remained under LP. In the wild bank voles the absolute BAT weight was seasonally constant, while the significant differences in the lipid droplet size were observed. The smallest lipid droplets (mean, 11 μm(2)) were seen in winter; they increased by 30 % in spring and reached the highest size (24 μm(2)) in summer. Lipid peroxidation in the BAT did not differ significantly between the seasons, although high intraseason variation of this process was noted. The laboratory experiment revealed that the size of lipid droplets was determined by photoperiod; SP induced 13-fold decrease, and continuous exposure to LP brought about a further 2.5-fold increase in the size of lipid droplets. Conversely, a significant decrease in lipid peroxidation was seen in LP bank voles in comparison with the SP animals. The data indicate that short photoperiod is responsible for the small size of lipid droplets in the BAT of bank voles during winter, which may be a necessary requirement for high thermogenic capacity of the tissue. Photoperiod appears also to affect lipid peroxidation in the BAT of these animals.

Sediment quantity and quality in three impoundments in Massachusetts

USGS Publications Warehouse

Zimmerman, Marc James; Breault, Robert F.

2003-01-01

As part of a study with an overriding goal of providing information that would assist State and Federal agencies in developing screening protocols for managing sediments impounded behind dams that are potential candidates for removal, the U.S Geological Survey determined sediment quantity and quality at three locations: one on the French River and two on Yokum Brook, a tributary to the west branch of the Westfield River. Data collected with a global positioning system, a geographic information system, and sediment-thickness data aided in the creation of sediment maps and the calculation of sediment volumes at Perryville Pond on the French River in Webster, Massachusetts, and at the Silk Mill and Ballou Dams on Yokum Brook in Becket, Massachusetts. From these data the following sediment volumes were determined: Perryville Pond, 71,000 cubic yards, Silk Mill, 1,600 cubic yards, and Ballou, 800 cubic yards. Sediment characteristics were assessed in terms of grain size and concentrations of potentially hazardous organic compounds and metals. Assessment of the approaches and methods used at study sites indicated that ground-penetrating radar produced data that were extremely difficult and time-consuming to interpret for the three study sites. Because of these difficulties, a steel probe was ultimately used to determine sediment depth and extent for inclusion in the sediment maps. Use of these methods showed that, where sampling sites were accessible, a machine-driven coring device would be preferable to the physically exhausting, manual sediment-coring methods used in this investigation. Enzyme-linked immunosorbent assays were an effective tool for screening large numbers of samples for a range of organic contaminant compounds. An example calculation of the number of samples needed to characterize mean concentrations of contaminants indicated that the number of samples collected for most analytes was adequate; however, additional analyses for lead, copper, silver, arsenic, total petroleum hydrocarbons, and chlordane are needed to meet the criteria determined from the calculations. Particle-size analysis did not reveal a clear spatial distribution pattern at Perryville Pond. On average, less than 65 percent of each sample was greater in size than very fine sand. The sample with the highest percentage of clay-sized particles (24.3 percent) was collected just upstream from the dam and generally had the highest concentrations of contaminants determined here. In contrast, more than 90 percent of the sediment samples in the Becket impoundments had grain sizes larger than very fine sand; as determined by direct observation, rocks, cobbles, and boulders constituted a substantial amount of the material impounded at Becket. In general, the highest percentages of the finest particles, clays, occurred in association with the highest concentrations of contaminants. Enzyme-linked immunosorbent assays of the Perryville samples showed the widespread presence of petroleum hydrocarbons (16 out of 26 samples), polycyclic aromatic hydrocarbons (23 out of 26 samples), and chlordane (18 out of 26 samples); polychlorinated biphenyls were detected in five samples from four locations. Neither petroleum hydrocarbons nor polychlorinated biphenyls were detected at Becket, and chlordane was detected in only one sample. All 14 Becket samples contained polycyclic aromatic hydrocarbons. Replicate quality-control analyses revealed consistent results between paired samples. Samples from throughout Perryville Pond contained a number of metals at potentially toxic concentrations. These metals included arsenic, cadmium, copper, lead, nickel, and zinc. At Becket, no metals were found in elevated concentrations. In general, most of the concentrations of organic compounds and metals detected in Perryville Pond exceeded standards for benthic organisms, but only rarely exceeded standards for human contact. The most highly contaminated samples were

Metals and bacteria partitioning to various size particles in Ballona Creek storm water runoff.

PubMed

Brown, Jeffrey S; Stein, Eric D; Ackerman, Drew; Dorsey, John H; Lyon, Jessica; Carter, Patrick M

2013-02-01

Many storm water best management practice (BMP) devices function primarily by capturing particulate matter to take advantage of the well-documented association between storm water particles and pollutants. The hydrodynamic separation or settling methods used by most BMP devices are most effective at capturing medium to large particles; however, these may not be the most predominant particles associated with urban runoff. The present study examined particle size distribution in storm water runoff from an urban watershed in southern California and investigated the pollutant-particle associations of metals (Cu, Pb, Ni, and Zn) and bacteria (enterococci and Escherichia coli). During small storm events (≤0.7 cm rain), the highest concentration of pollutants were associated with a <6-µm filter fraction, which accounted for 70% of the per storm contaminant mass but made up more than 20% of the total particle mass. The pollutant-particle association changed with storm size. Most pollutant mass was associated with >35 µm size particles during a 5-cm rain event. These results suggest that much of the contaminant load in storm water runoff will not be captured by the most commonly used BMP devices, because most of these devices (e.g., hydrodynamic separators) are unable to capture particles smaller than 75 µm. Copyright © 2012 SETAC.

Dextran and Polymer Polyethylene Glycol (PEG) Coating Reduce Both 5 and 30 nm Iron Oxide Nanoparticle Cytotoxicity in 2D and 3D Cell Culture

PubMed Central

Yu, Miao; Huang, Shaohui; Yu, Kevin Jun; Clyne, Alisa Morss

2012-01-01

Superparamagnetic iron oxide nanoparticles are widely used in biomedical applications, yet questions remain regarding the effect of nanoparticle size and coating on nanoparticle cytotoxicity. In this study, porcine aortic endothelial cells were exposed to 5 and 30 nm diameter iron oxide nanoparticles coated with either the polysaccharide, dextran, or the polymer polyethylene glycol (PEG). Nanoparticle uptake, cytotoxicity, reactive oxygen species (ROS) formation, and cell morphology changes were measured. Endothelial cells took up nanoparticles of all sizes and coatings in a dose dependent manner, and intracellular nanoparticles remained clustered in cytoplasmic vacuoles. Bare nanoparticles in both sizes induced a more than 6 fold increase in cell death at the highest concentration (0.5 mg/mL) and led to significant cell elongation, whereas cell viability and morphology remained constant with coated nanoparticles. While bare 30 nm nanoparticles induced significant ROS formation, neither 5 nm nanoparticles (bare or coated) nor 30 nm coated nanoparticles changed ROS levels. Furthermore, nanoparticles were more toxic at lower concentrations when cells were cultured within 3D gels. These results indicate that both dextran and PEG coatings reduce nanoparticle cytotoxicity, however different mechanisms may be important for different size nanoparticles. PMID:22754315

Enhancing the Damping Behavior of Dilute Zn-0.3Al Alloy by Equal Channel Angular Pressing

NASA Astrophysics Data System (ADS)

Demirtas, M.; Atli, K. C.; Yanar, H.; Purcek, G.

2017-06-01

The effect of grain size on the damping capacity of a dilute Zn-0.3Al alloy was investigated. It was found that there was a critical strain value (≈1 × 10-4) below and above which damping of Zn-0.3Al showed dynamic and static/dynamic hysteresis behavior, respectively. In the dynamic hysteresis region, damping resulted from viscous sliding of phase/grain boundaries, and decreasing grain size increased the damping capacity. While the quenched sample with 100 to 250 µm grain size showed very limited damping capacity with a loss factor tanδ of less than 0.007, decreasing grain size down to 2 µm by equal channel angular pressing (ECAP) increased tanδ to 0.100 in this region. Dynamic recrystallization due to microplasticity at the sample surface was proposed as the damping mechanism for the first time in the region where the alloy showed the combined aspects of dynamic and static hysteresis damping. In this region, tanδ increased with increasing strain amplitude, and ECAPed sample showed a tanδ value of 0.256 at a strain amplitude of 2 × 10-3, the highest recorded so far in the damping capacity-related studies on ZA alloys.

Characterization of free amino acids, bacteria and fungi in size-segregated atmospheric aerosols in boreal forest: seasonal patterns, abundances and size distributions

NASA Astrophysics Data System (ADS)

Helin, Aku; Sietiö, Outi-Maaria; Heinonsalo, Jussi; Bäck, Jaana; Riekkola, Marja-Liisa; Parshintsev, Jevgeni

2017-11-01

Primary biological aerosol particles (PBAPs) are ubiquitous in the atmosphere and constitute ˜ 30 % of atmospheric aerosol particle mass in sizes > 1 µm. PBAP components, such as bacteria, fungi and pollen, may affect the climate by acting as cloud-active particles, thus having an effect on cloud and precipitation formation processes. In this study, size-segregated aerosol samples (< 1.0, 1-2.5, 2.5-10 and > 10 µm) were collected in boreal forest (Hyytiälä, Finland) during a 9-month period covering all seasons and analysed for free amino acids (FAAs), DNA concentration and microorganism (bacteria, Pseudomonas and fungi). Measurements were performed using tandem mass spectrometry, spectrophotometry and qPCR, respectively. Meteorological parameters and statistical analysis were used to study their atmospheric implication for results. Distinct annual patterns of PBAP components were observed, late spring and autumn being seasons of dominant occurrence. Elevated abundances of FAAs and bacteria were observed during the local pollen season, whereas fungi were observed at the highest level during autumn. Meteorological parameters such as air and soil temperature, radiation and rainfall were observed to possess a close relationship with PBAP abundances on an annual scale.

Pt nanocatalysts supported on reduced graphene oxide for selective conversion of cellulose or cellobiose to sorbitol.

PubMed

Wang, Ding; Niu, Wenqi; Tan, Minghui; Wu, Mingbo; Zheng, Xuejun; Li, Yanpeng; Tsubaki, Noritatsu

2014-05-01

Pt nanocatalysts loaded on reduced graphene oxide (Pt/RGO) were prepared by means of a convenient microwave-assisted reduction approach with ethylene glycol as reductant. The conversion of cellulose or cellobiose into sorbitol was used as an application reaction to investigate their catalytic performance. Various metal nanocatalysts loaded on RGO were compared and RGO-supported Pt exhibited the highest catalytic activity with 91.5 % of sorbitol yield from cellobiose. The catalytic performances of Pt nanocatalysts supported on different carbon materials or on silica support were also compared. The results showed that RGO was the best catalyst support, and the yield of sorbitol was as high as 91.5 % from cellobiose and 58.9 % from cellulose, respectively. The improvement of catalytic activity was attributed to the appropriate Pt particle size and hydrogen spillover effect of Pt/RGO catalyst. Interestingly, the size and dispersion of supported Pt particles could be easily regulated by convenient adjustment of the microwave heating temperature. The catalytic performance was found to initially increase and then decrease with increasing particle size. The optimum Pt particle size was 3.6 nm. These findings may offer useful guidelines for designing novel catalysts with beneficial catalytic performance for biomass conversion. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Improving quality of an innovative pea puree by high hydrostatic pressure.

PubMed

Klug, Tâmmila Venzke; Martínez-Sánchez, Ascensión; Gómez, Perla A; Collado, Elena; Aguayo, Encarna; Artés, Francisco; Artés-Hernández, Francisco

2017-10-01

The food industry is continuously innovating to fulfill consumer demand for new, healthy, ready-to-eat products. Pea purees could satisfy this trend by increasing the intake of legumes, which are an important source of nutrients. Moreover, sensorial properties like viscosity could be improved by high hydrostatic pressure (HHP). In this study the effect of a boiling treatment (10 min) followed by HHP at 550 kPa (0, 5 or 10 min) on the rheological properties, associated with enzymatic activity and particle size, as well as on the microbial and sensory quality of a pea-based puree stored for 36 days at 5 °C, has been assessed. The particle size of pea puree decreased after all processing treatments, but increased during storage in HHP-treated samples. Conversely, boiling treatment showed an increase in polygalacturonase activity at the end of the storage period, with a decrease in particle size, viscosity and stability. However, 5 min of 550 kPa HHP showed the highest mean particle size, mean surface diameter and viscosity regarding the remaining treatments. The microbial load remained low during storage. HHP treatment can be used by the food industry to improve the rheological properties, viscosity and stability of pea purees. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

An adjustable multi-scale single beam acoustic tweezers based on ultrahigh frequency ultrasonic transducer.

PubMed

Chen, Xiaoyang; Lam, Kwok Ho; Chen, Ruimin; Chen, Zeyu; Yu, Ping; Chen, Zhongping; Shung, K Kirk; Zhou, Qifa

2017-11-01

This paper reports the fabrication, characterization, and microparticle manipulation capability of an adjustable multi-scale single beam acoustic tweezers (SBAT) that is capable of flexibly changing the size of "tweezers" like ordinary metal tweezers with a single-element ultrahigh frequency (UHF) ultrasonic transducer. The measured resonant frequency of the developed transducer at 526 MHz is the highest frequency of piezoelectric single crystal based ultrasonic transducers ever reported. This focused UHF ultrasonic transducer exhibits a wide bandwidth (95.5% at -10 dB) due to high attenuation of high-frequency ultrasound wave, which allows the SBAT effectively excite with a wide range of excitation frequency from 150 to 400 MHz by using the "piezoelectric actuator" model. Through controlling the excitation frequency, the wavelength of ultrasound emitted from the SBAT can be changed to selectively manipulate a single microparticle of different sizes (3-100 μm) by using only one transducer. This concept of flexibly changing "tweezers" size is firstly introduced into the study of SBAT. At the same time, it was found that this incident ultrasound wavelength play an important role in lateral trapping and manipulation for microparticle of different sizes. Biotechnol. Bioeng. 2017;114: 2637-2647. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Dimensions of design space: a decision-theoretic approach to optimal research design.

PubMed

Conti, Stefano; Claxton, Karl

2009-01-01

Bayesian decision theory can be used not only to establish the optimal sample size and its allocation in a single clinical study but also to identify an optimal portfolio of research combining different types of study design. Within a single study, the highest societal payoff to proposed research is achieved when its sample sizes and allocation between available treatment options are chosen to maximize the expected net benefit of sampling (ENBS). Where a number of different types of study informing different parameters in the decision problem could be conducted, the simultaneous estimation of ENBS across all dimensions of the design space is required to identify the optimal sample sizes and allocations within such a research portfolio. This is illustrated through a simple example of a decision model of zanamivir for the treatment of influenza. The possible study designs include: 1) a single trial of all the parameters, 2) a clinical trial providing evidence only on clinical endpoints, 3) an epidemiological study of natural history of disease, and 4) a survey of quality of life. The possible combinations, samples sizes, and allocation between trial arms are evaluated over a range of cost-effectiveness thresholds. The computational challenges are addressed by implementing optimization algorithms to search the ENBS surface more efficiently over such large dimensions.

Larval assemblages of large and medium-sized pelagic species in the Straits of Florida

NASA Astrophysics Data System (ADS)

Richardson, David E.; Llopiz, Joel K.; Guigand, Cedric M.; Cowen, Robert K.

2010-07-01

Critical gaps in our understanding of the distributions, interactions, life histories and preferred habitats of large and medium-size pelagic fishes severely constrain the implementation of ecosystem-based, spatially structured fisheries management approaches. In particular, spawning distributions and the environmental characteristics associated with the early life stages are poorly documented. In this study, we consider the diversity, assemblages, and associated habitat of the larvae of large and medium-sized pelagic species collected during 2 years of monthly surveys across the Straits of Florida. In total, 36 taxa and 14,295 individuals were collected, with the highest diversity occurring during the summer and in the western, frontal region of the Florida Current. Only a few species (e.g. Thunnus obesus, T. alalunga, Tetrapturus pfluegeri) considered for this study were absent. Small scombrids (e.g. T. atlanticus, Katsuwonus pelamis, Auxis spp.) and gempylids dominated the catch and were orders of magnitude more abundant than many of the rare species (e.g. Thunnus thynnus,Kajikia albida). Both constrained (CCA) and unconstrained (NMDS) multivariate analyses revealed a number of species groupings including: (1) a summer Florida edge assemblage (e.g. Auxis spp., Euthynnus alleterattus, Istiophorus platypterus); (2) a summer offshore assemblage (e.g. Makaira nigricans, T. atlanticus, Ruvettus pretiosus, Lampris guttatus); (3) an ubiquitous assemblage (e.g. K. pelamis, Coryphaena hippurus, Xiphias gladius); and (4) a spring/winter assemblage that was widely dispersed in space (e.g. trachipterids). The primary environmental factors associated with these assemblages were sea-surface temperature (highest in summer-early fall), day length (highest in early summer), thermocline depth (shallowest on the Florida side) and fluorescence (highest on the Florida side). Overall, the results of this study provide insights into how a remarkable diversity of pelagic species spatially and temporally partition spawning within a region that is characterized by dynamic oceanography and strong habitat gradients.

The cutting effect of male flower on the size of the fruit cob, the size of the fruit and seeds in Porang (Amorphophallus muelleri Blume)

NASA Astrophysics Data System (ADS)

Harijati, Nunung; Navisya, Hikma Isnailul; Diao, Ying

2017-11-01

The formation of fruits and seeds depends on pollination and fertilization. For the fruit itself, its formation and final size are closely correlated with the gibberellin content. It is known that pollen is one source of gibberellins. Porang is a member of the genus Amorphophallus, which has a compound fruit arranged on a cob and monoecious. Each fruit may contain a single seed or multiple seeds. The purpose of this study was to determine the effect of male flower removal on the size of the fruit cob, the number of fruit per ear, the seed number per ear, the fruit size and the proportion of fruit that contains single or multiple seeds. Removing male flowers is done by cutting the cluster of male flowers when the flower is very young and still wrapped with a sheath. The resulting data were analyzed using an unpaired t-test. Analysis of the results shows that the diameter and length of the cob of a cut-male flower are lower than the normal flower. The number of fruit or seed numbers per ear of the cut-male flower is lower than the normal flower. However, the length and diameter of the fruit of the cut-male flower is higher than the normal flower. The normal flower has higher numbers of individual fruit with single seeds than cut-male flowers, and cut-male flowers have higher incidences of fruit containing more than one seed (multiple seeds). The maximum seed number of individual fruit of normal flowers and cut-male flowers is 4 and 7 seeds respectively. In categories of fruit containing multiple seeds, the individual fruit containing 2 seeds has the highest proportion of cut-male flowers.

Study of constraints in using household NaCl salt for retrospective dosimetry

NASA Astrophysics Data System (ADS)

Elashmawy, M.

2018-05-01

Thermoluminescence (TL) characteristics of 5 different household NaCl salts and one analytical salt were determined to investigate the possible factors that affect the reliability of using household salt for retrospective dosimetry. Salts' TL sensitivities were found to be particle-size dependent and approached saturation at the largest size, whereas for salts that have the same particle size, the TL sensitivity depended on their origin. TL dependence on the particle size interprets significant variations in TL response reported in the literature for the same salt patch. The first TL readout indicated that all salts have similar glow curves with one distinctive peak. Typical second TL readout at two different doses showed a dramatic decrease in TL sensitivity associated with a significant change in the glow curve structure possessing two prominent peaks. Glow curve deconvolution (GCD) of the first TL readout for all salts yielded 6 individual glow peaks of first-order kinetics, whereas in GCD of second TL readouts, 5 individual glow peaks of second-order kinetics were obtained. Similarities in the glow curve structures of the first and second TL readouts suggest that additives such as KIO3 and MgCO3 have no effect on the TL process. Fading effect was evaluated for the salt of highest TL sensitivity, and it was found that the integral TL intensity decreased gradually and lost 40% of its initial value over 2 weeks, after which it remained constant. Results conclude that a household salt cannot be used for retrospective dosimetry without considering certain constraints such as the salt's origin and particle size. Furthermore, preparedness for radiological accidents and accurate dose reconstructions require that most of the commonly distributed household salt brands should be calibrated in advance and stored in a repository to be recalled in case of accidents.

Population size and trend of Yellow-billed Loons in northern Alaska

USGS Publications Warehouse

Earnst, Susan L.; Stehn, R.A.; Platte, Robert; Larned, W.W.; Mallek, E.J.

2005-01-01

The Yellow-billed Loon (Gavia adamsii) is of conservation concern due to its restricted range, small population size, specific habitat requirements, and perceived threats to its breeding and wintering habitat. Within the U.S., this species breeds almost entirely within the National Petroleum Reserve-Alaska, nearly all of which is open, or proposed to be opened, for oil development. Rigorous estimates of Yellow-billed Loon population size and trend are lacking but essential for informed conservation. We used two annual aerial waterfowl surveys, conducted 1986a??2003 and 1992a??2003, to estimate population size and trend on northern Alaskan breeding grounds. In estimating population trend, we used mixed-effects regression models to reduce bias and sampling error associated with improvement in observer skill and annual effects of spring phenology. The estimated population trend on Alaskan breeding grounds since 1986 was near 0 with an estimated annual change of a??0.9% (95% CI of a??3.6% to +1.8%). The estimated population size, averaged over the past 12 years and adjusted by a correction factor based on an intensive, lake-circling, aerial survey method, was 2221 individuals (95% CI of 1206a??3235) in early June and 3369 individuals (95% CI of 1910a??4828) in late June. Based on estimates from other studies of the proportion of loons nesting in a given year, it is likely that <1000 nesting pairs inhabit northern Alaska in most years. The highest concentration of Yellow-billed Loons occurred between the Meade and Ikpikpuk Rivers; and across all of northern Alaska, 53% of recorded sightings occurred within 12% of the area.

[Effects of temperature increase on zooplankton size spectra in thermal discharge seawaters near a power plant, China].

PubMed

Yu, Jing; Zhu, Yi Feng; Dai, Mei Xia; Lin, Xia; Mao, Shuo Qian

2017-05-18

Utilizing the plankton 1 (505 Μm), 2 (160 Μm), 3 (77 Μm) nets to seasonally collect zooplankton samples at 10 stations and the corresponding abundance data was obtained. Based on individual zooplankton biovolume, size groups were classified to test the changes in spatiotemporal characteristics of both Sheldon and normalized biovolume size spectra in thermal discharge seawaters near the Guohua Power Plant, so as to explore the effects of temperature increase on zooplankton size spectra in the seawaters. The results showed that the individual biovolume of zooplankton ranged from 0.00012 to 127.0 mm 3 ·ind -1 , which could be divided into 21 size groups, and corresponding logarithmic ranges were from -13.06 to 6.99. According to Sheldon size spectra, the predominant species to form main peaks of the size spectrum in different months were Copepodite larvae, Centropages mcmurrichi, Calanus sinicus, fish larvae, Sagitta bedoti, Sagitta nagae and Pleurobrachia globosa, and minor peaks mostly consisted of individuals with smaller larvae, Cyclops and Paracalanus aculeatus. In different warming sections, Copepodite larvae, fish eggs and Cyclops were mostly unaffected by the temperature increase, while the macrozooplankton such as S. bedoti, S. nagae, P. globosa, C. sinicus and Beroe cucumis had an obvious tendency to avoid the outfall of the power plant. Based on the results of normalized size spectra, the intercepts from low to high occurred in November, February, May and August, respectively. At the same time, the minimum slope was found in February, and similarly bigger slopes were observed in May and August. These results indicated that the proportion of small zooplankton was highest in February, while the proportions of the meso- and macro-zooplankton were relatively high in May and August. Among different sections, the slope in the 0.2 km section was minimum, which increased with the increase of section distance to the outfall. The result obviously demonstrated that the closer the distance was from outfall of the power plant, the smaller the zooplankton became. On the whole, the average intercept of normalized size spectrum in Xiangshan Bay was 4.68, and the slope was -0.655.

Interactions between freshwater snails and tadpoles: competition and facilitation.

PubMed

Brönmark, Christer; Rundle, Simon D; Erlandsson, Ann

1991-06-01

Freshwater snails and anuran tadpoles have been suggested to have their highest population densities in ponds of intermediate size where abiotic disturbance (e.g. desiccation) is low and large predators absent. Both snails and tadpoles feed on periphytic algae and, thus, there should be a large potential for competitive interactions to occur between these two distantly related taxa. In a field experiment we examined the relative strength of competition between two closely related snail species, Lymnaea stagnalis and L. peregra, and between L. stagnalis and tadpoles of the common frog, Rana temporaria. Snail growth and egg production and tadpole size at and time to metamorphosis were determined. Effects on the common food source, periphyton, were monitored with the aid of artificial substrates. Periphyton dry weight was dramatically reduced in the presence of snails and/or tadpoles. There were no competitive effects on growth or egg production of the two snail species when they were coexisting. Mortality of L. peregra was high (95%) after reproduction, but independent of treatment. Growth of L. stagnalis was reduced only at the highest tadpole densities, whereas egg production was reduced both by intraspecific competition and by competition with tadpoles. Differences in egg production were retained after tadpole metamorphosis. Tadpole larval period increased, weight of metamorphosing frogs decreased and growth rate was reduced as a function of increasing tadpole density. However, contrary to expectation, snails had a positive effect on tadpole larval period, weight and growth rate. Further, in experimental containers without snails there was a dense growth of the filamentous green alga Cladophora sp. We suggest that the facilitative effects of snails on tadpoles are due to an "indirect mutualistic" mechanism, involving competition between food sources of different quality (microalgae and Cladophora sp.) and tadpoles being competitively dominant over snails for the preferred food source (microalgae). In the presence of tadpoles snails will be forced to feed on low-quality Cladophora, increasing nutrient turnover rates, which results in enhanced productivity of microalgae, increasing tadpole food resources. Thus, tadpoles have a negative effect on snails through resource depression, while snails facilitate tadpole growth through an indirect enhancement of food availability.

Effect of substrates on Zinc Oxide thin films fabrication using sol-gel method

NASA Astrophysics Data System (ADS)

Kadir, Rosmalini Ab; Taib, Nurmalina Mohd; Ahmad, Wan Rosmaria Wan; Aziz, Anees Abdul; Sabirin Zoolfakar, Ahmad

2018-03-01

The properties of ZnO thin films were deposited on three different substrates via dip coating method was investigated. The films were prepared on glass, ITO and p-type silicon. Characterization of the film revealed that the properties of the dip coated ZnO thin films were influenced by the type of substrates. The grains on ITO and glass were ∼10 nm in size while the grains on wafer agglomerate together to form a denser film. Studies of the optical properties using UV-VIS-NIR of the fabricated films demonstrated that glass has the highest transmittance compared to ITO.

Oil-in-water emulsification using confined impinging jets.

PubMed

Siddiqui, Shad W; Norton, Ian T

2012-07-01

A confined impinging jet mixing device has been used to investigate the continuous sunflower oil/water emulsification process under turbulent flow conditions with oil contents between 5% (v/v) and 10% (v/v). Various emulsifiers (Tween20, Span80, Whey Protein, Lecithin and Sodium Dodecylsulphate) varying in molecular weights have been studied. Mean droplet sizes varied with the emulsifiers used and smallest droplets were obtained under fully turbulent flow regime, i.e. at the highest jet flow rate and highest jet Reynolds Number conditions. Sodium Dodecylsulfate (SDS) produced droplets in the range of 3.8 μm while 6 μm droplets were obtained with Whey Protein. Similar droplet sizes were obtained under fully turbulent flow conditions (610 mL/min; Reynolds Number=13,000) for oil content varying between 5% (v/v) and 10% (v/v). To investigate the smallest droplet size possible in the device, the emulsion was passed through the geometry multiple times. Multi-pass emulsification resulted in reduction in droplet size indicating that longer residence in the flow field under high shear condition allowed for breakage of droplets as well as the time for the emulsifier to stabilize the newly formed droplets, decreasing the impact of coalescence. This was confirmed by timescale analysis of the involved process steps for the droplet data obtained via experiments. Dependence of mean droplet size on the o/w interfacial tension and peak energy dissipation was also investigated. Copyright © 2012 Elsevier Inc. All rights reserved.

48 CFR 52.247-61 - F.o.b. Origin-Minimum Size of Shipments.

Code of Federal Regulations, 2011 CFR

2011-10-01

... be the highest applicable minimum weight which will result in the lowest freight rate (or per car... minimum weight, the Contractor agrees to ship such scheduled quantity in one shipment. The Contractor...

48 CFR 52.247-61 - F.o.b. Origin-Minimum Size of Shipments.

Code of Federal Regulations, 2013 CFR

2013-10-01

... be the highest applicable minimum weight which will result in the lowest freight rate (or per car... minimum weight, the Contractor agrees to ship such scheduled quantity in one shipment. The Contractor...

48 CFR 52.247-61 - F.o.b. Origin-Minimum Size of Shipments.

Code of Federal Regulations, 2014 CFR

2014-10-01

... be the highest applicable minimum weight which will result in the lowest freight rate (or per car... minimum weight, the Contractor agrees to ship such scheduled quantity in one shipment. The Contractor...

48 CFR 52.247-61 - F.o.b. Origin-Minimum Size of Shipments.

Code of Federal Regulations, 2012 CFR

2012-10-01

... be the highest applicable minimum weight which will result in the lowest freight rate (or per car... minimum weight, the Contractor agrees to ship such scheduled quantity in one shipment. The Contractor...

Petrography and physicomechanical properties of rocks from the Ambela granitic complex, NW Pakistan.

PubMed

Arif, Mohammad; Bukhari, S Wajid Hanif; Muhammad, Noor; Sajid, Muhammad

2013-01-01

Petrography and physicomechanical properties of alkali granites, alkali quartz syenite, and nepheline syenite from Ambela, NW Pakistan, have been investigated. Whereas the alkali quartz syenite and most of the alkali granites are megaporphyritic, the nepheline syenite and some of the alkali granites are microporphyritic. Their phenocryst shape and size and abundance of groundmass are also different. The values of unconfined compressive strength (UCS) are the lowest and highest for megaporphyritic alkali granite and alkali quartz syenite, respectively. However, all the four rock types are moderately strong. Correspondingly, their specific gravity and water absorption values are within the permissible range for use as construction material. The UCS for the alkali quartz syenite is the highest, most probably because (i) it has roughly equal amounts of phenocryst and groundmass, (ii) it displays maximum size contrast between phenocryst and groundmass, (iii) its phenocrysts are highly irregular, and (iv) it contains substantial amounts of quartz.

Petrography and Physicomechanical Properties of Rocks from the Ambela Granitic Complex, NW Pakistan

PubMed Central

Arif, Mohammad; Bukhari, S. Wajid Hanif; Muhammad, Noor; Sajid, Muhammad

2013-01-01

Petrography and physicomechanical properties of alkali granites, alkali quartz syenite, and nepheline syenite from Ambela, NW Pakistan, have been investigated. Whereas the alkali quartz syenite and most of the alkali granites are megaporphyritic, the nepheline syenite and some of the alkali granites are microporphyritic. Their phenocryst shape and size and abundance of groundmass are also different. The values of unconfined compressive strength (UCS) are the lowest and highest for megaporphyritic alkali granite and alkali quartz syenite, respectively. However, all the four rock types are moderately strong. Correspondingly, their specific gravity and water absorption values are within the permissible range for use as construction material. The UCS for the alkali quartz syenite is the highest, most probably because (i) it has roughly equal amounts of phenocryst and groundmass, (ii) it displays maximum size contrast between phenocryst and groundmass, (iii) its phenocrysts are highly irregular, and (iv) it contains substantial amounts of quartz. PMID:23861654

Influence of nanometer scale particulate fillers on some properties of microfilled composite resin.

PubMed

Garoushi, Sufyan; Lassila, Lippo V J; Vallittu, Pekka K

2011-07-01

The aim of this study was to evaluate the effect of different weight fractions of nanometer sized particulate filler on properties of microfilled composite resin. Composite resin was prepared by mixing 33 wt% of resin matrix to the 67 wt% of silane treated microfine silica particulate fillers with various fractions of nanometer sized fillers (0, 10, 15, 20, 30 wt%) using a high speed mixing machine. Test specimens made of the composites were tested with a three-point bending test with a speed of 1.0 mm/min until fracture. Surface microhardess (Vicker's microhardness) was also determined. The volumetric shrinkage in percent was calculated as a buoyancy change in distilled water by means of the Archimedes principle. The degree of monomer conversion (DC%) of the experimental composites containing different nanofiller fractions was measured using FTIR spectroscopy. Surface roughness (Ra) was determined using a surface profilometer. Nanowear measurements were carried out using a nanoindentation device. The water uptake of specimens was also measured. Parameters were statistically analysed by ANOVA (P < 0.05). The group without nanofillers showed the highest flexural strength and modulus, DC% and Ra value. The group with 30% nanofillers had the highest water uptake and volumetric shrinkage. No significant difference was found in Vicker's microhardness and the nanowear of the composites. The plain microfilled composite demonstrated superior properties compared to the composites loaded with nanofillers with the exception of surface roughness.

On the biology and food of small-sized fish from North and Baltic Sea areas. IV. Investigations on an eulittoral mud flat at Sylt Island

NASA Astrophysics Data System (ADS)

Zander, C. Dieter; Hartwig, Eike

1982-03-01

The fish fauna of an eulittoral mud flat was investigated at Sylt Island (North Sea) with special regard to its food uptake. During the course of a year the following species were caught: Pomatoschistus microps, Anguilla anguilla (elvers), Zoarces viviparus, and Gasterosteus aculeatus. Considering the potentially available food, the most abundant organisms of the benthos were harpacticoids and nematodes, whereas in the phytal layer gastropods and gammarids were dominant. The benthic biomass was found to be greatest in spring, while phytal organisms were most abundant in late summer. The greatest fish density was stated in September 1974 though only P. microps was present. The fish biomass was highest in spring when the elvers appeared. The main food of P. microps was epibenthos; in the diet of A. anguilla phytal organisms dominated over epibenthos, in G. aculeatus suprabenthic organisms were also present. The most prominent food component by biomass was gammarids in all investigated fish, whereas harpacticoids were only dominant in number. During the course of the year the biomass of ingested food yielded highest values in summer and autumn, but lowest in winter. A very great predatory activity was found in September 1974, which possibly caused a grazing effect on harpacticoids. An estimation of the turnover rate of small-sized fish in this month led to a value of 70 mg dry weight m-2 · d-1.

Photochemical formation of chitosan-stabilized near-infrared-absorbing silver Nanoworms: A "Green" synthetic strategy and activity on Gram-negative pathogenic bacteria.

PubMed

Marpu, Sreekar; Kolailat, Samar S; Korir, Daniel; Kamras, Brian L; Chaturvedi, Ratnesh; Joseph, Abel; Smith, Christopher M; Palma, Misael C; Shah, Jyoti; Omary, Mohammad A

2017-12-01

A facile, single-step, non-seeded photochemical protocol for producing a new type of anisotropic silver nanostructure, "nanoworms", with curved longer dimensions and smooth, rounded edges. The nanoworms exhibit surface plasmon resonance (SPR) absorption in the near-infrared window (NIRW) region and are stabilized using biocompatible polymer chitosan, rendering biocompatibility and amplified safety for biological utility of the composition. Both NIRW-absorbing nanoworms and visible-absorbing nanospheres herein are attained exclusively by employing green chemistry principles. Contrary to seed-mediated or polyol techniques, the protocol demonstrates the feasibility to selectively synthesize NIRW-absorbing silver nanostructures in a single step and in complete absence of any known reducing agent. The effect of irradiation, pH, and concentration of starting materials on the formation of nanoworms vs nanospheres is investigated in detail and analyzed by optical spectroscopy and electron microscopy. The dominant SPR obtained in the NIRW region of the nanoworms results from anisotropic AgNPs, as opposed to agglomeration. From TEM images, it is also very clear that a strong correlation exists between the SPR peak maximum and the size distribution of the anisotropic nanoworm structures, with SPR peak maximum exhibiting red shift with the increase in the size of the nanoworm population. Although there is significant size variation of different nanoworms of a given population, all samples exhibit remarkable stability. The nanoworms retained their NIRW-absorbing features even at physiological pH and at a constant ionic strength. The nanodispersions also retained their SPR features in King's B medium. Antipathogenic assays reveal that the anisotropic NIRW-absorbing nanoworms exhibit the highest growth inhibition compared to other spherical nanosilver and molecular silver forms on Gram-negative pathogenic bacteria, Pseudomonas syringae pv. maculicola ES4326 and P. syringae pv. tomato DC3000. These results underscore shape effects of AgNPs and suggest that nanoworms favor the adhesion to (curved) rod-shaped Gram-negative bacteria, resulting in the highest inhibition compared to isotropic AgNPs (smaller spheres), sulfa antibiotics (silver sulfadiazine), and silver ions (AgNO 3 ). Copyright © 2017 Elsevier Inc. All rights reserved.

Hospital-level changes in adult ICU bed supply in the United States

PubMed Central

Wallace, David J.; Seymour, Christopher W.; Kahn, Jeremy M.

2017-01-01

Objective Although the number of intensive care beds in the United States is increasing, little is known about the hospitals responsible for this growth. We sought to better characterize national growth in intensive care beds by identifying hospital-level factors associated with increasing numbers of intensive care beds over time. Design We performed a repeated-measures time series analysis of hospital-level intensive care bed supply using data from Centers for Medicare and Medicaid Services. Setting All United States acute care hospitals with adult intensive care beds over the years 1996 to 2011. Measurements & Main Results We described the number of beds, teaching status, ownership, intensive care occupancy and urbanicity for each hospital in each year of the study. We then examined the relationship between increasing intensive care beds and these characteristics, controlling for other factors. The study included 4,457 hospitals and 55,865 hospital-years. Overall, the majority of intensive care bed growth occurred in teaching hospitals (net +13,471 beds, 72.1% of total growth), hospitals with 250 or more beds (net +18,327 beds, 91.8% of total growth) and hospitals in the highest quartile of occupancy (net +10,157 beds, 54.0% of total growth). In a longitudinal multivariable model, larger hospital size, teaching status, and high intensive care occupancy were associated with subsequent-year growth. Furthermore, the effects of hospital size and teaching status were modified by occupancy: the greatest odds of increasing intensive care unit beds were in hospitals with 500 or more beds in the highest quartile of occupancy (adjusted OR: 18.9; 95% CI: 14.0 – 25.5; p<0.01) and large teaching hospitals in the highest quartile of occupancy (adjusted OR: 7.3; 95% CI: 5.3 – 9.9; p<0.01). Conclusions Increasingly, intensive care bed expansion in the United States is occurring in larger hospitals and teaching centers, particularly following a year with high intensive care unit occupancy. PMID:27661861

An approach to assess the Particulate Matter exposure for the population living around a cement plant: modelling indoor air and particle deposition in the respiratory tract

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

Sánchez-Soberón, Francisco; Mari, Montse; Kumar, Vikas

In this paper we studied the exposure to three size fractions of outdoor particulate matter (PM{sub 10}, PM{sub 2.5}, and PM{sub 1}) collected in an area influenced by a cement plant. For that purpose, three groups of population were evaluated (children, adults and retired) in two seasons (summer and winter). Outdoor measured PM concentrations, as well as physiological parameters and activity patterns of the three groups of population were used as input data in two different models. The first one was an indoor air quality model, used to elucidate indoor PM concentrations in different microenvironments. The second one was amore » dosimetry model, used to evaluate the internal exposure and the distribution of the different PM fractions in the respiratory tract. Results from the indoor air quality model showed that special attention must be paid to the finest particles, since they penetrate indoors in a greater degree. Highest pulmonary doses for the three PM sizes were reported for retired people, being this a result of the high amount of time in outdoor environments exercising lightly. For children, the exposure was mainly influenced by the time they also spend outdoors, but in this case due to heavy intensity activities. It was noticed that deposition of fine particles was more significant in the pulmonary regions of children and retired people in comparison with adults, which has implications in the expected adverse health effects for those vulnerable groups of population. - Highlights: • PM deposition in the respiratory tract was evaluated for three population groups. • Activity patterns and different microenvironments were used in our calculation. • Outdoor activities are the main contributors to PM deposited mass. • Children experienced the highest deposition dose in the pulmonary region. • Retired registered the highest deposited mass in the respiratory tract as a whole.« less

Geochemistry and health risk assessment of arsenic exposure to street dust in the zinc smelting district, Northeast China.

PubMed

Xu, Sujuan; Zheng, Na; Liu, Jingshuang; Wang, Yang; Chang, Shouzhi

2013-02-01

The aim of this study was to investigate arsenic (As) accumulation in street dust and health risk of population. The investigation concentrated on: a. pollution levels of As in street dust; b. spatial distribution of As in street dust; c. physicochemical properties analysis of street dust; and d. assessment of population health risk due to As exposure to street dust. As concentration in street dust ranged from 3.33 to 185.1 mg kg(-1), with a mean of 33.10 mg kg(-1), which was higher than the background value of Liaoning soil. As contamination level of the area closing to Huludao Zinc Plant (HZP) was highest. Spatial variation showed that the pollution center was close to HZP, formed radial distribution pattern and extended to the northeast and southwest of HZP. The pH and organic matter of street dust were both higher than the background values of soil in Liaoning. There was significantly negative correlation between As concentration and the pH. The mass percentages of particles 180-100, <100-75, <75-63, and <63 μm were 29.8, 3.7, 21.3, and 4.2 %, respectively. The highest of As concentration was found in the smallest particle size (<63 μm). As loadings in the particles of grain size 180-100 and <75-63 μm were higher than other particle fractions. Results of the risk assessment indicated that the highest risk was associated with the ingestion of street dust particles. Health risk for different use scenarios to human decreased in the order of HZP > Industrial district > School > Commercial center > Residential area. Around HZP, Hazard Index (HI) for children and cancer risk of As by street dust exposure exceeded the acceptable values. It indicated that there was a potential adverse effect on children health by As exposure to the street dust of Huludao.

Size effect of SnO2 nanoparticles on bacteria toxicity and their membrane damage.

PubMed

Chávez-Calderón, Adriana; Paraguay-Delgado, Francisco; Orrantia-Borunda, Erasmo; Luna-Velasco, Antonia

2016-12-01

Semiconductor SnO 2 nanoparticles (NPs) are being exploited for various applications, including those in the environmental context. However, toxicity studies of SnO 2 NPs are very limited. This study evaluated the toxic effect of two sizes of spherical SnO 2 NPs (2 and 40 nm) and one size of flower-like SnO 2 NPs (800 nm) towards the environmental bacteria E. coli and B. subtilis. SnO 2 NPs were synthesized using a hydrothermal or calcination method and they were well characterized prior to toxicity assessment. To evaluate toxicity, cell viability and membrane damage were determined in cells (1 × 10 9  CFU mL -1 ) exposed to up to 1000 mg L -1 of NPs, using the plate counting method and confocal laser scanning microscopy. Spherical NPs of smaller primary size (E2) had the lowest hydrodynamic size (226 ± 96 nm) and highest negative charge (-30.3 ± 10.1 mV). Smaller spherical NPs also showed greatest effect on viability (IC 50  > 500 mg L -1 ) and membrane damage of B. subtilis, whereas E. coli was unaffected. Scanning electron microscopy confirmed the membrane damage of exposed B. subtilis and also exhibited the attachment of E2 NPs to the cell surface, as well as the elongation of cells. It was also apparent that toxicity was caused solely by NPs, as released Sn 4+ was not toxic to B. subtilis. Thus, surface charge interaction between negatively charged SnO 2 NPs and positively charged molecules on the membrane of the Gram positive B. subtilis was indicated as the key mechanism related to toxicity of NPs. Copyright © 2016 Elsevier Ltd. All rights reserved.

Laboratory evaluation of the particle size effect on the performance of an elastomeric half-mask respirator against ultrafine combustion particles.

PubMed

He, Xinjian; Grinshpun, Sergey A; Reponen, Tiina; Yermakov, Michael; McKay, Roy; Haruta, Hiroki; Kimura, Kazushi

2013-08-01

This study quantified the particle size effect on the performance of elastomeric half-mask respirators, which are widely used by firefighters and first responders exposed to combustion aerosols. One type of elastomeric half-mask respirator equipped with two P-100 filters was donned on a breathing manikin while challenged with three combustion aerosols (originated by burning wood, paper, and plastic). Testing was conducted with respirators that were fully sealed, partially sealed (nose area only), or unsealed to the face of a breathing manikin to simulate different faceseal leakages. Three cyclic flows with mean inspiratory flow (MIF) rates of 30, 85, and 135 L/min were tested for each combination of sealing condition and combustion material. Additional testing was performed with plastic combustion particles at other cyclic and constant flows. Particle penetration was determined by measuring particle number concentrations inside and outside the respirator with size ranges from 20 to 200 nm. Breathing flow rate, particle size, and combustion material all had significant effects on the performance of the respirator. For the partially sealed and unsealed respirators, the penetration through the faceseal leakage reached maximum at particle sizes >100 nm when challenged with plastic aerosol, whereas no clear peaks were observed for wood and paper aerosols. The particles aerosolized by burning plastic penetrated more readily into the unsealed half-mask than those aerosolized by the combustion of wood and paper. The difference may be attributed to the fact that plastic combustion particles differ from wood and paper particles by physical characteristics such as charge, shape, and density. For the partially sealed respirator, the highest penetration values were obtained at MIF = 85 L/min. The unsealed respirator had approximately 10-fold greater penetration than the one partially sealed around the bridge of the nose, which indicates that the nose area was the primary leak site.

Correlation Of Giant Nuclei With Cloud Droplet Concentration

NASA Astrophysics Data System (ADS)

Jha, V.; Hudson, J. G.; Noble, S.

2011-12-01

The effect of giant nuclei (GN; larger than 1 micrometer particles produced by wind on the ocean surface) on warm rain has been debated for decades. During RICO (Rain in Cumulus over the Ocean) Hudson et al. (2011) found a negative correlation (R) between CCN concentrations at 1% supersaturation (S) and large cloud droplet concentrations (Fig. 1A). This reversal from positive R for CCN with total (or small) cloud droplet concentrations (left side of Fig. 1A) was explained by the greater competition for condensate, which thus limits droplet sizes when CCN concentrations are higher. The negative R increased in magnitude with altitude, and the droplet size where the maximum negative R occurred increased with altitude (Fig. 1A). However, at all altitudes this negative R decreased in magnitude for even larger cloud and drizzle drops (right side of Fig. 1A except highest altitude). The decrease in magnitude of the negative R was greater for increasing drop sizes at higher altitudes. Thus, at the higher altitudes, R for CCN with large drizzle drops was of low negative magnitude and even positive at the highest RICO altitudes. The disparity between CCN and drizzle drop concentrations precluded a causal relationship. But the high R between GN and drizzle drop concentrations at the highest altitudes (Fig. 1B) and the comparable concentrations indicated that GN were engendering drizzle. This is supported by the increasing R with altitude of the GN-drizzle drop R (right side of Fig. 1B). The conclusion of a GN-drizzle connection is also supported by the fact that CCN concentrations should inhibit drizzle. This analysis of Hudson et al. (2011) is here expanded to include correlations of CCN concentrations at lower S with cloud and drizzle drop concentrations to investigate intermediate relationships; i.e., between large nuclei (i.e., 0.1-1 micrometer; critical S 0.1-0.01%) and drizzle drop concentrations. A shortcoming of Hudson et al. (2011) was the small number of high altitude flights, which limited the significance of the R values. The very recent (July 2011) ICE-T project was a similar study in the same region (Caribbean). The greater number of high altitude cloud measurements during the summer season should provide better statistics to test the GN warm rain hypothesis.

Models to compare management options for a protogynous fish.

PubMed

Heppell, Selina S; Heppell, Scott A; Coleman, Felicia C; Koenig, Christopher C

2006-02-01

Populations of gag (Mycteroperca microlepis), a hermaphroditic grouper, have experienced a dramatic shift in sex ratio over the past 25 years due to a decline in older age classes. The highly female-skewed sex ratio can be predicted as a consequence of increased fishing mortality that truncates the age distribution, and raises some concern about the overall fitness of the population. Management efforts may need to be directed toward maintenance of sex ratio as well as stock size, with evaluations of recruitment based on sex ratio or male stock size in addition to the traditional female-based stock-recruitment relationship. We used two stochastic, age-structured models to heuristically compare the effects of reducing fishing mortality on different life history stages and the relative impact of reductions in fertilization rates that may occur with highly skewed sex ratios. Our response variables included population size, sex ratio, lost egg fertility, and female spawning stock biomass. Population growth rates were highest for scenarios that reduced mortality for female gag (nearshore closure), while improved sex ratios were obtained most quickly with spawning reserves. The effect of reduced fertility through sex ratio bias was generally low but depended on the management scenario employed. Our results demonstrate the utility of evaluation of fishery management scenarios through model analysis and simulation, the synergistic interaction of life history and response to changes in mortality rates, and the importance of defining management goals.

Variation in freshwater growth and development among five New England Atlantic salmon (Salmo salar) populations reared in a common environment

USGS Publications Warehouse

Obedzinski, M.; Letcher, B.H.

2004-01-01

We examined phenotypic variation in growth and development from the eyed-egg stage to the age-1+ smolt stage among five New England populations of Atlantic salmon (Salmo salar: East Machias, Narraguagus, Sheepscot, Penobscot, Connecticut) reared in a common laboratory environment. Study populations originated from rivers varying in size, latitude, and level of hatchery supplementation and included one reintroduced population (Connecticut was a recipient of Penobscot origin stock). Phenotypic trait differences were found among populations, and the degree of stock variation depended on ontogeny. Eggs were smaller and hatched sooner in the Penobscot (a northern, intensively managed population), but no stock differences were detected in size or growth efficiency from the onset of exogenous feeding to age 0+ summer. Differences again emerged in age 0+ autumn, with the degree of bimodality in length-frequency distributions differing among stocks; the Connecticut had the highest proportion of upper-mode fish and, ultimately, age-1+ smolts. Although genetic effects could not be entirely separated from maternal effects for egg size variation, it is likely that differences in hatch timing and smolt age had a genetic basis. Early emphasis on age-1+ hatchery-reared smolts in the Connecticut may have led to divergence in smolt age between the Penobscot and Connecticut populations in less than eight generations. ?? 2004 NRC Canada.

Hierarchical porous silicon carbide with controlled micropores and mesopores for electric double layer capacitors

NASA Astrophysics Data System (ADS)

Kim, Myeongjin; Oh, Ilgeun; Kim, Jooheon

2015-05-01

Three-dimensional hierarchical micro and mesoporous silicon carbide spheres (MMPSiC) are prepared by the template method and carbonization reaction via the aerosol spray drying method. The mesopores are generated by the self-assembly of the structure-directing agents, whereas the micropores are derived from the partial evaporation of Si atoms during carbonization. To investigate the effect of mesopore size on electrochemical performance, three types of MMPSiC with different mesopore size were fabricated by using three different structure directing agents (cetyltriethylammonium bromide (CTAB), Polyethylene glycol hexadecyl ether (Brij56), and Poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol) (P123)). The MMPSiC electrode prepared with Brij56 exhibits the highest charge storage capacity with a specific capacitance of 253.7 F g-1 at a scan rate of 5 mV s-1 and 87.9% rate performance from 5 to 500 mV s-1 in 1 M Na2SO4 aqueous electrolyte. The outstanding electrochemical performance might be because of the ideal mesopore size, which effectively reduces the resistant pathways for ion diffusion in the pores and provides a large accessible surface area for ion transport/charge storage. These encouraging results demonstrate that the MMPSiC prepared with Brij56 is a promising candidate for high performance electrode materials for supercapacitors.

Morphological integration in the gorilla, chimpanzee, and human neck.

PubMed

Arlegi, Mikel; Gómez-Robles, Aida; Gómez-Olivencia, Asier

2018-06-01

Although integration studies are important to understand the evolution of organisms' traits across phylogenies, vertebral integration in primates is still largely unexplored. Here we describe and quantify patterns of morphological integration and modularity in the subaxial cervical vertebrae (C3-C7) in extant hominines incorporating the potential influence of size. Three-dimensional landmarks were digitized on 546 subaxial cervical vertebrae from 141 adult individuals of Gorilla gorilla, Pan troglodytes, and Homo sapiens. Integration and modularity, and the influence of size effects, were quantified using geometric morphometric approaches. All subaxial cervical vertebrae from the three species show a strong degree of integration. Gorillas show the highest degree of integration; conversely, humans have the lowest degree of integration. Analyses of allometric regression residuals show that size is an important factor promoting integration in gorillas, with lesser influence in chimpanzees and almost no effect in humans. Results point to a likely ancestral pattern of integration in non-human hominines, whereby the degree of integration decreases from cranial to caudal positions. Humans deviate from this pattern in the cranialmost (C3) and, to a lesser extent, in the caudalmost (C7) vertebrae, which are less integrated. These differences can be tentatively related to the emergence of bipedalism due to the presence of modern human-like C3 in australopiths, which still preserve a more chimpanzee-like C7. © 2018 Wiley Periodicals, Inc.

Structural Characterization of IgG1 mAb Aggregates and Particles Generated under Various Stress Conditions

PubMed Central

Telikepalli, Srivalli N.; Kumru, Ozan S.; Kalonia, Cavan; Esfandiary, Reza; Joshi, Sangeeta B.; Middaugh, C. Russell; Volkin, David B.

2014-01-01

IgG1 mAb solutions were prepared with and without sodium chloride and subjected to different environmental stresses. Formation of aggregates and particles of varying size was monitored by a combination of size exclusion chromatography (SEC), Nanosight Tracking Analysis (NTA), Micro-flow Imaging (MFI), turbidity, and visual assessments. Stirring and heating induced the highest concentration of particles. In general, the presence of NaCl enhanced this effect. The morphology of the particles formed from mAb samples exposed to different stresses was analyzed from TEM and MFI images. Shaking samples without NaCl generated the most fibrillar particles, while stirring created largely spherical particles. The composition of the particles was evaluated for covalent cross-linking by SDS-PAGE, overall secondary structure by FTIR microscopy, and surface apolarity by extrinsic fluorescence spectroscopy. Freeze-thaw and shaking led to particles containing protein with native-like secondary structure. Heating and stirring produced IgG1 containing aggregates and particles with some non-native disulfide crosslinks, varying levels of intermolecular beta sheet content, and increased surface hydrophobicity. These results highlight the importance of evaluating protein particle morphology and composition, in addition to particle number and size distributions, to better understand the effect of solution conditions and environmental stresses on the formation of protein particles in mAb solutions. PMID:24452866

Structural characterization of IgG1 mAb aggregates and particles generated under various stress conditions.

PubMed

Telikepalli, Srivalli N; Kumru, Ozan S; Kalonia, Cavan; Esfandiary, Reza; Joshi, Sangeeta B; Middaugh, C Russell; Volkin, David B

2014-03-01

IgG1 mAb solutions were prepared with and without sodium chloride and subjected to different environmental stresses. Formation of aggregates and particles of varying size was monitored by a combination of size-exclusion chromatography, Nanoparticle Tracking Analysis, Micro-flow Imaging (MFI), turbidity, and visual assessments. Stirring and heating induced the highest concentration of particles. In general, the presence of NaCl enhanced this effect. The morphology of the particles formed from mAb samples exposed to different stresses was analyzed from transmission electron microscopy and MFI images. Shaking samples without NaCl generated the most fibrillar particles, whereas stirring created largely spherical particles. The composition of the particles was evaluated for covalent cross-linking by SDS-PAGE, overall secondary structure by FTIR microscopy, and surface apolarity by extrinsic fluorescence spectroscopy. Freeze-thaw and shaking led to particles containing protein with native-like secondary structure. Heating and stirring produced IgG1-containing aggregates and particles with some non-native disulfide cross-links, varying levels of intermolecular beta sheet content, and increased surface hydrophobicity. These results highlight the importance of evaluating protein particle morphology and composition, in addition to particle number and size distributions, to better understand the effect of solution conditions and environmental stresses on the formation of protein particles in mAb solutions. © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association.

Phosphorus removal by electric arc furnace steel slag adsorption

NASA Astrophysics Data System (ADS)

Lim, J. W.; Lee, K. F.; Chong, Thomas S. Y.; Abdullah, L. C.; Razak, M. A.; Tezara, C.

2017-10-01

As to overcome the eutrophication in lakes and reservoirs which is resulted from excessive input of phosphorus due to rapid urbanization or uncontrolled agricultural activities, Electric Arc Furnace steel slag (EAFS), a steelmaking by-product, in which the disposal of this industrial waste considered economically unfavourable yet it’s physical and chemical properties exhibits high potential to be great P adsorbent. The objective of this study was to identify most suitable mathematical model in description of adsorption by using traditional batch experiment and to investigate the effect on Phosphorus removal efficiency and Phosphorus removal capacity by EAFS adsorption through variation of parameters such as pH, size of slag and initial concentration of Phosphorus. Result demonstrated that, Langmuir is suitable in describing Phosphorus removal mechanisms with the Maximum Adsorption Capacity, Q m of 0.166 mg/g and Langmuir Constant, KL of 0.03519 L/mg. As for effect studies, smaller size of adsorbent shows higher percentage (up to 37.8%) of Phosphorus removal compared to the larger size. Besides that, the experiment indicated a more acidic environment is favourable for Phosphorus removal and the amount of Phosphorus adsorbed at pH 3.0 was the highest. In addition, the adsorption capacity increases steadily as the initial Phosphorus concentration increases but it remained steady at 100mg P/L. Eventually, this study serves as better understanding on preliminary studies of P removal mechanisms by EAFS.

Proximate content of wild and cultured eel (Anguilla bicolor) in different part of body

NASA Astrophysics Data System (ADS)

Wijayanti, I.; Susilo, E. S.

2018-02-01

Proximate content in fish varies depends on intrinsic and extrinsic factors. Intrinsic factors include species, sexual maturity, size and body parts. Extrinsic factors include habitat, season and type of food (diet). This study aimed to know the effect of fish body parts (intrinsic factor) on proximate levels in wild and cultured eel (extrinsic). The experimental design used factorial completely randomized design with two factors 2x3. The first factor is the habitat of eel (wild and cultured) and the second factor is the part of the body (head, body and tail) with five replications. The result of statistical analysis showed that there was interaction between fish habitat and body part on moisture, protein, ash and carbohydrate content (P <0.05), but no interaction on fat content and energy (P> 0.05). The highest water content (67.02%) was found in head of wild and the lowest one (59.44%) in the tail of wild eel; The highest protein content (18.09%) was found in the body of cultured eel and the lowest one (15.72%) was in the body of wild eel; The highest ash content (3.73%) was the head of wild eel and the lowest (1.32%) was in the body of cultured eel; The highest carbohydrate (3.73%) was found in the head of cultured eel and the lowest one (0.16%) was in the body of cultured. The wild eel had higher fat content and energy than cultured one, while the fat content and energy in body and tail were higher than in head.

Temporal evolution of ultrafine particles and of alveolar deposited surface area from main indoor combustion and non-combustion sources in a model room.

PubMed

Manigrasso, Maurizio; Vitali, Matteo; Protano, Carmela; Avino, Pasquale

2017-11-15

Aerosol number size distributions, PM mass concentrations, alveolar deposited surface areas (ADSAs) and VOC concentrations were measured in a model room when aerosol was emitted by sources frequently encountered in indoor environments. Both combustion and non-combustion sources were considered. The most intense aerosol emission occurred when combustion sources were active (as high as 4.1×10 7 particlescm -3 for two meat grilling sessions; the first with exhaust ventilation, the second without). An intense spike generation of nucleation particles occurred when appliances equipped with brush electric motors were operating (as high as 10 6 particlescm -3 on switching on an electric drill). Average UFP increments over the background value were highest for electric appliances (5-12%) and lowest for combustion sources (as low as -24% for tobacco cigarette smoke). In contrast, average increments in ADSA were highest for combustion sources (as high as 3.2×10 3 μm 2 cm -3 for meat grilling without exhaust ventilation) and lowest for electric appliances (20-90μm 2 cm -3 ). The health relevance of such particles is associated to their ability to penetrate cellular structures and elicit inflammatory effects mediated through oxidative stress in a way dependent on their surface area. The highest VOC concentrations were measured (PID probe) for cigarette smoke (8ppm) and spray air freshener (10ppm). The highest PM mass concentration (PM 1 ) was measured for citronella candle burning (as high as 7.6mgm -3 ). Copyright © 2017 Elsevier B.V. All rights reserved.

Microstructure Evolution and Related Magnetic Properties of Cu-Zr-Al-Gd Phase-Separating Metallic Glasses

NASA Astrophysics Data System (ADS)

Kim, Sang Jun; Kim, Jinwoo; Park, Eun Soo

2018-04-01

We carefully investigated the correlation between microstructures and magnetic properties of Cu-Zr-Al-Gd phase-separating metallic glasses (PSMGs). The saturation magnetizations of the PSMGs were determined by total Gd contents of the alloys, while their coercivity exhibits a large deviation by the occurrence of phase separation due to the boundary pinning effect of hierarchically separated amorphous phases. Especially, the PSMGs containing Gd-rich amorphous nanoparticles show the highest coercivity which can be attributed to the size effect of the ferromagnetic amorphous phase. Furthermore, the selective crystallization of ferromagnetic amorphous phases can affect the magnetization behavior of the PSMGs. Our results could provide a novel strategy for tailoring unique soft magnetic properties of metallic glasses by introducing hierarchically separated amorphous phases and controlling their crystallinity.

Effect of Dispersion Method on Stability and Dielectric Strength of Transformer Oil-Based TiO2 Nanofluids.

PubMed

Lv, Yu-Zhen; Li, Chao; Sun, Qian; Huang, Meng; Li, Cheng-Rong; Qi, Bo

2016-12-01

Dispersion stability of nanoparticles in the liquid media is of great importance to the utilization in practice. This study aims to investigate the effects of mechanical dispersion method on the dispersibility of functionalized TiO 2 nanoparticles in the transformer oil. Dispersion methods, including stirring, ultrasonic bath, and probe processes, were systematically tested to verify their versatility for preparing stable nanofluid. The test results reveal that the combination of ultrasonic bath process and stirring method has the best dispersion efficiency and the obtained nanofluid possesses the highest AC breakdown strength. Specifically, after aging for 168 h, the size of nanoparticles in the nanofluid prepared by the combination method has no obvious change, while those obtained by the other three paths are increased obviously.

Microstructure Evolution and Related Magnetic Properties of Cu-Zr-Al-Gd Phase-Separating Metallic Glasses

NASA Astrophysics Data System (ADS)

Kim, Sang Jun; Kim, Jinwoo; Park, Eun Soo

2018-06-01

We carefully investigated the correlation between microstructures and magnetic properties of Cu-Zr-Al-Gd phase-separating metallic glasses (PSMGs). The saturation magnetizations of the PSMGs were determined by total Gd contents of the alloys, while their coercivity exhibits a large deviation by the occurrence of phase separation due to the boundary pinning effect of hierarchically separated amorphous phases. Especially, the PSMGs containing Gd-rich amorphous nanoparticles show the highest coercivity which can be attributed to the size effect of the ferromagnetic amorphous phase. Furthermore, the selective crystallization of ferromagnetic amorphous phases can affect the magnetization behavior of the PSMGs. Our results could provide a novel strategy for tailoring unique soft magnetic properties of metallic glasses by introducing hierarchically separated amorphous phases and controlling their crystallinity.

Distribution of heavy metals and foraminiferal assemblages in sediments of Biscayne Bay, Florida, USA

USGS Publications Warehouse

Carnahan, E.A.; Hoare, A.M.; Hallock, P.; Lidz, B.H.; Reich, C.D.

2008-01-01

Heavy-metal pollution is an issue of concern in estuaries influenced by agriculture, urban, and harbor activities. Foraminiferal assemblages have been shown to be effective indicators of pollution. Sediment samples (n = 110) from Biscayne Bay were analyzed for heavy metals, foraminiferal assemblages, and grain-size distribution. Highest Cu, Zn, Cr, Hg, Pb, and Ni concentrations were found closest to Miami and near the mouths of several canals along the western margin of the bay. Few samples exceeded limits of possible biological effects as defined by previous studies. Ammonia and Cribroelphidium, two known stress-tolerant genera, correlated positively with Cu, Zn, Hg, and Ni (r ??? 0.43). Symbiont-bearing foraminifers, Archaias, Laevipeneroplis, and Androsina, correlated negatively with Cu, Zn, Hg, and Ni (r ??? -0.26).

Analysis of intrinsic and extrinsic factors influencing the dynamics of bovine Eimeria spp. from central-eastern Poland.

PubMed

Tomczuk, Krzysztof; Grzybek, Maciej; Szczepaniak, Klaudiusz; Studzińska, Maria; Demkowska-Kutrzepa, Marta; Roczeń-Karczmarz, Monika; Klockiewicz, Maciej

2015-11-30

Eimeria infections are common in cattle worldwide, however, little is known about the invasion dynamics of this unicellular parasite. Therefore, the aim of this study was to analyze intrinsic (host age) and extrinsic (herd size and management system) factors influencing the dynamics of Eimeria spp. found in calves from CE Poland. Fecal samples were collected from 356 calves from different types of management systems and from different herd sizes. Flotation and McMaster method were used for parasitological investigation. Oocysts were differentiated on the basis of morphological criteria. Eight Eimeria species were identified and mean species richness (MSR) was significantly affected by host age. The highest MSR was noted for middle age animals. There was an association between species, with a highly significant co-occurrence of Eimeria bovis with Eimeria zuernii. The presence of E. bovis significantly increased the percentage of individuals carrying E. zuernii. The presence of E. bovis significantly increased the percentage of individuals carrying Eimeria canadensis. The overall prevalence of Eimeria spp. reached 52.8% and was significantly affected by the age of cows, with the highest prevalence in animals between 5-10 months old. The most prevalent species were E. bovis (37.4%), E. zuernii (19.9%) and E. canadensis (12.1%). The prevalence of E. bovis was affected by host age (the highest prevalence in age class 2 animals) and management type (the highest prevalence in individuals raised in groups). The prevalence of E. zuernii was affected by age (the lowest prevalence was noted in the oldest individuals) and herd size (individuals infected were present only in the middle and large size herds), whereas the prevalence of E. canadensis was affected by all three factors. Overall, mean OPG of the combined Eimeria spp. was 458.84 (37.93) and differed significantly between age classes. Mean OPGs were generally low for young and mature animals but high for middle age class animals. There was no significant influence of extrinsic factors on OPG. Taking into consideration the presented results, it is necessary to underline the role of intrinsic and extrinsic factors affecting the prevalence and abundance of Eimeria spp. in calves. Understanding the dynamics of Eimeria infections in calves may help to overcome this most common bovine parasite. Copyright © 2015 Elsevier B.V. All rights reserved.

Photolysis of the organic UV filter, avobenzone, combined with octyl methoxycinnamate by nano-TiO2 composites.

PubMed

Kim, E J; Kim, M J; Im, N R; Park, S N

2015-08-01

A protection of the skin from harmful UV rays is important in preventing the skin damage and skin aging when exposed to sunlight. Titanium dioxide composites are used as a UV filter in sunscreen products combined with organic compounds such as butyl methoxydibenzoyl methane (avobenzone) and octyl methoxycinnamate (OMC) to improve the function of the sunscreen. In this study, the photolysis of avobenzone and OMC caused by the photocatalytic TiO2 nano composites (NCs) is investigated. Three different types of oil/water (O/W) sunscreen formulations containing avobenzone and OMC were prepared. Each formulation contained one of three different types of surface modified TiO2 NCs, which were WP-S (small sized hydrophilic TiO2NCs, ~10nm), OP-S (small sized hydrophobic TiO2NCs, ~15nm), and OP-L (large sized hydrophobic TiO2NCs, ~200nm). The physicochemical properties of the NCs were analyzed using biophysical tools. Addition of a different size of TiO2NCs into O/W sunscreen formulations significantly increased the photolysis of OMC. Effect of quercetin on degradation of avobenzone and OMC by the NCs was also studied for all three formulations. Although the OP-S NCs showed the lowest photocatalytic ability and the highest UV blocking capability, the NCs promoted the photolysis of OMC to the greatest extent. These results can be utilized to design more effective sunscreens, which could potentially ensure optimal photo-protection. Copyright © 2015 Elsevier B.V. All rights reserved.

Effects of wet deposition on the abundance and size distribution of black carbon in East Asia

NASA Astrophysics Data System (ADS)

Kondo, Y.; Moteki, N.; Oshima, N.; Ohata, S.; Koike, M.; Shibano, Y.; Takegawa, N.; Kita, K.

2016-05-01

An improved understanding of the variations in the mass concentration and size distribution of black carbon (BC) in the free troposphere (FT) over East Asia, where BC emissions are very high, is needed to reliably estimate the radiative forcing of BC in climate models. We measured these parameters and the carbon monoxide (CO) concentration by conducting the Aerosol Radiative Forcing in East Asia (A-FORCE) 2013W aircraft campaign in East Asia in winter 2013 and compared these data with measurements made in the same region in spring 2009. The median BC concentrations in the FT originating from North China (NC) and South China (SC) showed different seasonal variations, which were primarily caused by variations in meteorological conditions. CO concentrations above the background were much higher in SC than in NC in both seasons, suggesting a more active upward transport of CO. In SC, precipitation greatly increased from winter to spring, leading to an increased wet deposition of BC. As a result, the median BC concentration in the FT was highest in SC air in winter. This season and region were optimal for the effective transport of BC from the planetary boundary layer to the FT. The count median diameters of the BC size distributions generally decreased with altitude via wet removal during upward transport. The altitude dependence of the BC size distributions was similar in winter and spring, in accord with the similarity in the BC mixing state. The observed BC concentrations and microphysical properties will be useful for evaluating the performance of climate models.

[Anticaries effectiveness of fluoride toothpaste: a meta-analysis].

PubMed

Chaves, Sônia Cristina Lima; Vieira-da-Silva, Lígia Maria

2002-10-01

To carry out a meta-analysis on the effectiveness of fluoride toothpaste for reducing dental caries to calculate the effect size of different hypothesis. MEDLINE and LILACS databases were studied in the period from 1980 to 1998. To evaluate the quality of the studies, methodological rigor criteria proposed by Kay & Locker (1996) were applied after the criteria were submitted to an expert committee of CNPq (National Scientific Council of Brazil) senior researchers. Of 43 papers selected, 22 met the proposed criteria. The effect size of intervention was calculated from differences among the groups and the overall effect of five groups of hypothesis. The high concentration of fluoride in the toothpaste is associated with a larger effect (overall effect = -0.17 CI 95% -0.22/-0.12). The largest caries reductions were observed when comparing fluoride toothpastes and no fluoride toothpastes (overall effect = -0.29 IC 95% -0.34/-0.24). The addiction of antimicrobial agents (overall effect = -0.03 IC 95% -0.07/+0.02), differences in abrasive systems (overall effect = -0.02 IC 95% -0.09/+0.04) and active components do not increase the effectiveness of fluoride toothpastes (overall effect = -0.04 IC 95% -0.10/+0.01). The highest caries reductions were seen in studies where there was supervised tooth brushing. This review reinforced the importance of tooth brushing with fluoride toothpastes for controlling dental caries. However it showed the emphasis put on medical approaches for disease control rather than specific educational actions. The heterogeneity of the results shows the need to consider issues such as the scenario for implementing preventive methods in the evaluation process.

A Multimodality Ultramicrospectroscope (MUMS): Nanoscale Imaging with Integrated Spectroscopies for Chemical and Biomolecular Identification

DTIC Science & Technology

2010-11-10

nanoparticles, and nanoshells by making sub 100 nm diameter nanoshells to mesoscopic sized nanoparticles (gold meatballs ) and micron sized nanoshells. In...mesoscopic gold ‘ meatballs ’, gold bipyrimids etc. In addition nanoparticles such as the nanostar demonstrate some of the highest LSPR sensitivity but...20, 535-538 (2008). 64. H. Wang and N. J. Halas, “Mesoscopic Au ‘ Meatball ’ Particles”, Advanced Materials 20, 820-825 (2008). 65. S. Priya

Influence of Under-layer Morphology on Structural and Magnetic Properties of Sputtered Co81Pd19 Films

NASA Astrophysics Data System (ADS)

Ponchaiya, Pairin; Rattanasakulthong, Watcharee

2017-09-01

Sputtered Co81Pd19 films with thickness of about 60 nm were deposited on various under-layers (Co, Ni, Cr and Al) and on glass substrate. Structural, morphological and magnetic properties of Co81Pd19 films were investigated. All of prepared Co81Pd19 film showed CoPd-FCC phase in (111) direction on CoO-FCC (111), NiO-FCC (200), Cr-BCC (200) and (201) and AlO-FCC (200) phases of Co, Ni, Cr and Al under-layer, respectively. AFM images revealed that the film on Cr under-layers and glass substrate exhibited the maximum roughness with the highest grain size and the minimum roughness with the continuous grain size, respectively. Both parallel and perpendicular maximum coercive field were found in the film on glass under-layer and the film on Co-under-layer film showed the highest saturation magnetization from both in-plane and out-of-plane measurements. These results confirmed that the structural and magnetic properties of sputtered Co81Pd19 films were affected by under-layer surface roughness and morphology by the virtue of particle size and distribution on the under-layer film surface.

Validation of mothers' reports of dietary intake by four to seven year-old children.

PubMed Central

Basch, C E; Shea, S; Arliss, R; Contento, I R; Rips, J; Gutin, B; Irigoyen, M; Zybert, P

1990-01-01

The validity of mothers' recall of four to seven year-old children's diet was assessed among 46 first generation Latino immigrant families from the Dominican Republic by comparing intake recalled by the mother to unobtrusive home observations of children. Correlations were moderate to high for calories and for most nutrients. There were no differences in mean intake of total calories or in intake of most macronutrients and micronutrients assessed. At least two-thirds of the children in the lowest (or highest) quintile based on home observations were correctly classified into the lowest or second lowest (or highest) quintiles based on mother's reports for calories and most nutrients. For all food items that were both observed and reported, 51 percent of reported portion sizes were equivalent to observed portion sizes, 15.5 percent were smaller, and 33.5 percent were larger. There was fair to good agreement on the number of food items eaten, with the exception of vegetables. Mothers' recall appears to be useful for classifying children by intake of calories, macronutrients and micronutrients, but provides a somewhat less accurate measure of actual foods eaten, portion sizes, and nutrient levels consumed. PMID:2240296

Effect of annealing temperature on the size and magnetic properties of CoFe2O4 nanoparticle

NASA Astrophysics Data System (ADS)

Sunny, Annrose; Akshay, V. R.; Vasundhara, M.

2018-05-01

CoFe2O4 (CFO) nanoparticles (NPs) are synthesized using sol gel method and are annealed at 400, 600 and 800 °C for 4h. The crystal structure and morphology of the NPs are investigated through XRD and TEM analysis. The X- ray diffraction analysis shows that all the samples are well formed and attain a cubic structure with Fd-3m space group. The morphology of the material is found to be polygonal and the particle size of the NPs is increased with increase of annealing temperature as 400, 600 and 800 to be 20 nm, 30 nm and 70 nm respectively. The magnetic properties of the NPs are investigated using VSM and observed that the curie temperature for 400, 600 and 800 °C annealing temperature are 762 K, 780 K, 769 K respectively. The Ms of 600 sample is 80 emu/g. The 400 and 800 sample shows lower Ms value this is due to poor crystalanity and exaggerated grain growth at the respective temperatures. The coercivity of the sample shows linear dependence with particle size of the material the highest coercivity is obtained for 400 sample and low value for 800 sample.

When will bigger be (recalled) better? The influence of category size on JOLs depends on test format.

PubMed

Hourihan, Kathleen L; Tullis, Jonathan G

2015-08-01

Although it is well known that organized lists of words (e.g., categories) are recalled better than unrelated lists, little research has examined whether participants can predict how categorical relatedness influences recall. In two experiments, participants studied lists of words that included items from big categories (12 items), small categories (4 items), and unrelated items, and provided immediate JOLs. In Experiment 1, free recall was highest for items from large categories and lowest for unrelated items. Importantly, participants were sensitive to the effects of category size on recall, with JOLs to items from big categories actually increasing over the study list. In Experiment 2, one group of participants was cued to recall all exemplars from the categories in a blocked manner, whereas the other group was cued in a random order. As expected, the random group did not show the recall benefit for big categories over small categories observed in free recall, while the blocked group did. Critically, the pattern of metacognitive judgments closely matched actual cued recall performance. Participants' JOLs were sensitive to the interaction between category size and output order, demonstrating a relatively sophisticated strategy that incorporates the interaction of multiple extrinsic cues in predicting recall.

Revisiting Parallel Cyclic Reduction and Parallel Prefix-Based Algorithms for Block Tridiagonal System of Equations

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

Seal, Sudip K; Perumalla, Kalyan S; Hirshman, Steven Paul

2013-01-01

Simulations that require solutions of block tridiagonal systems of equations rely on fast parallel solvers for runtime efficiency. Leading parallel solvers that are highly effective for general systems of equations, dense or sparse, are limited in scalability when applied to block tridiagonal systems. This paper presents scalability results as well as detailed analyses of two parallel solvers that exploit the special structure of block tridiagonal matrices to deliver superior performance, often by orders of magnitude. A rigorous analysis of their relative parallel runtimes is shown to reveal the existence of a critical block size that separates the parameter space spannedmore » by the number of block rows, the block size and the processor count, into distinct regions that favor one or the other of the two solvers. Dependence of this critical block size on the above parameters as well as on machine-specific constants is established. These formal insights are supported by empirical results on up to 2,048 cores of a Cray XT4 system. To the best of our knowledge, this is the highest reported scalability for parallel block tridiagonal solvers to date.« less

Cellular Response of the Amoeba Acanthamoeba castellanii to Chlorine, Chlorine Dioxide, and Monochloramine Treatments ▿

PubMed Central

Mogoa, Emerancienne; Bodet, Charles; Morel, Franck; Rodier, Marie-Hélène; Legube, Bernard; Héchard, Yann

2011-01-01

Acanthamoeba castellanii is a free-living amoebae commonly found in water systems. Free-living amoebae might be pathogenic but are also known to bear phagocytosis-resistant bacteria, protecting these bacteria from water treatments. The mode of action of these treatments is poorly understood, particularly on amoebae. It is important to examine the action of these treatments on amoebae in order to improve them. The cellular response to chlorine, chlorine dioxide, and monochloramine was tested on A. castellanii trophozoites. Doses of disinfectants leading to up to a 3-log reduction were compared by flow cytometry and electron microscopy. Chlorine treatment led to size reduction, permeabilization, and retraction of pseudopods. In addition, treatment with chlorine dioxide led to a vacuolization of the cytoplasm. Monochloramine had a dose-dependent effect. At the highest doses monochloramine treatment resulted in almost no changes in cell size and permeability, as shown by flow cytometry, but the cell surface became smooth and dense, as seen by electron microscopy. We show that these disinfectants globally induced size reduction, membrane permeabilization, and morphological modifications but that they have a different mode of action on A. castellanii. PMID:21602398

A generalized public goods game with coupling of individual ability and project benefit

NASA Astrophysics Data System (ADS)

Zhong, Li-Xin; Xu, Wen-Juan; He, Yun-Xin; Zhong, Chen-Yang; Chen, Rong-Da; Qiu, Tian; Shi, Yong-Dong; Ren, Fei

2017-08-01

Facing a heavy task, any single person can only make a limited contribution and team cooperation is needed. As one enjoys the benefit of the public goods, the potential benefits of the project are not always maximized and may be partly wasted. By incorporating individual ability and project benefit into the original public goods game, we study the coupling effect of the four parameters, the upper limit of individual contribution, the upper limit of individual benefit, the needed project cost and the upper limit of project benefit on the evolution of cooperation. Coevolving with the individual-level group size preferences, an increase in the upper limit of individual benefit promotes cooperation while an increase in the upper limit of individual contribution inhibits cooperation. The coupling of the upper limit of individual contribution and the needed project cost determines the critical point of the upper limit of project benefit, where the equilibrium frequency of cooperators reaches its highest level. Above the critical point, an increase in the upper limit of project benefit inhibits cooperation. The evolution of cooperation is closely related to the preferred group-size distribution. A functional relation between the frequency of cooperators and the dominant group size is found.