bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation of real-time PCR for quantitative detection of Escherichia coli in beach water
Authors: Lam Jason Tszhin , Lui Edwin , Chau Simon , Kueh Cathie Show Wu , Yung Ying-kit , Yam Wing Cheong
Published: March 2014

The current investigation evaluated the use of real-time polymerase chain reaction (PCR) for quantitative detection of Escherichia coli in marine beach water. Densities of E. coli in 263 beach water samples collected from 13 bathing beaches in Hong Kong between November 2008 and December 2009 were determined using both real-time PCR and culture-based methods. Regression analysis showed that these two methods had a significant positive linear relationship with a correlation coefficient (r) of 0.64. Serial dilution of spiked samples indicated that the real-time PCR had a limit of quantification of 25 E. coli colonies in 100 mL water sample. This study showed that the rapid real-time PCR has potential to complement the traditional culture method of assessing fecal pollution in marine beach water.
Incorporating potable water sources and use habits into surveys that improve surrogate exposure estimates for water contaminants: the case of bisphenol A
Authors: Andra Syam S. , Makris Konstantinos C.
Published: March 2014

Human biomonitoring studies for water contaminants are often accompanied by surveys relying solely on total drinking water consumption rates, thus, failing to account for specific water sources (bottled and tap water) and use habits, such as water used for preparing cold/hot beverages (coffee, tea, juice, etc.). Despite the extensive use of bisphenol A (BPA) in polycarbonate (PC)-based water contact materials, rarely do BPA biomonitoring studies focus on various PC water uses and sources. Better resolved water consumption rates could reduce the uncertainty associated with surrogate daily BPA intake estimates using fine-tuned surveys. This approach provided a proof of concept on inclusion of water consumption from various sources and uses into estimates of daily intake for water contaminants like BPA found in water-contact materials. The next steps would be in quantifying the extent of improvement in exposure assessment that adds value to refined survey designs.
The first recorded outbreak of cryptosporidiosis due to Cryptosporidium cuniculus (formerly rabbit genotype), following a water quality incident
Authors: Puleston Richard L. , Mallaghan Cathy M. , Modha Deborah E. , Hunter Paul R. , Nguyen-Van-Tam Jonathan S. , Regan Christopher M. , Nichols Gordon L. , Chalmers Rachel M.
Published: March 2014

We report the first identified outbreak of cryptosporidiosis with Cryptosporidium cuniculus following a water quality incident in Northamptonshire, UK. A standardised, enhanced Cryptosporidium exposure questionnaire was administered to all cases of cryptosporidiosis after the incident. Stool samples, water testing, microscopy slides and rabbit gut contents positive for Cryptosporidium were typed at the Cryptosporidium Reference Unit, Singleton Hospital, Swansea. Twenty-three people were microbiologically linked to the incident although other evidence suggests an excess of 422 cases of cryptosporidiosis above baseline. Most were adult females; unusually for cryptosporidiosis there were no affected children identified under the age of 5 years. Water consumption was possibly higher than in national drinking water consumption patterns. Diarrhoea duration was negatively correlated to distance from the water treatment works where the contamination occurred. Oocyst counts were highest in water storage facilities. This outbreak is the first caused by C. cuniculus infection to have been noted and it has conclusively demonstrated that this species can be a human pathogen. Although symptomatically similar to cryptosporidiosis from C. parvum or C. hominis, this outbreak has revealed some differences, in particular no children under 5 were identified and females were over-represented. These dissimilarities are unexplained although we postulate possible explanations.
The potential of lipopolysaccharide as a real-time biomarker of bacterial contamination in marine bathing water
Authors: Sattar Anas A. , Jackson Simon K. , Bradley Graham
Published: March 2014

The use of total lipopolysaccharide (LPS) as a rapid biomarker for bacterial pollution was investigated at a bathing and surfing beach during the UK bathing season. The levels of faecal indicator bacteria Escherichia coli (E. coli), the Gram-positive enterococci, and organisms commonly associated with faecal material, such as total coliforms and Bacteroides, were culturally monitored over four months to include a period of heavy rainfall and concomitant pollution. Endotoxin measurement was performed using a kinetic Limulus Amebocyte Lysate (LAL) assay and found to correlate well with all indicators. Levels of LPS in excess of 50 Endotoxin Units (EU) mL−1 were found to correlate with water that was unsuitable for bathing under the current European regulations. Increases in total LPS, mainly from Gram-negative indicator bacteria, are thus a potential real-time, qualitative method for testing bacterial quality of bathing waters.
Surface water isolates of hemolytic and non-hemolytic Acinetobacter with multiple drug and heavy metal resistance ability
Authors: Akbulut Sevilay , Yilmaz Fadime , Icgen Bulent
Published: March 2014

Acinetobacter in surface waters are a major concern because of their rapid development of resistance to a wide range of antimicrobials and their ability to persist in these waters for a very long time. Four surface water isolates of Acinetobacter having both multidrug- and multimetal-resistant ability were isolated and identified through biochemical tests and 16S rDNA sequencing. Based on these analyses, two hemolytic isolates were affiliated with Acinetobacter haemolyticus with an accession number of X81662. The other two non-hemolytic isolates were identified as Acinetobacter johnsonii and Acinetobacter calcoaceticus and affiliated with accession numbers of Z93440 and AJ888983, respectively. The antibiotic and heavy metal resistance profiles of the isolates were determined by using 26 antibiotics and 17 heavy metals. Acinetobacter isolates displayed resistance to β-lactams, cephalosporins, aminoglycosides, and sulfonamides. The hemolytic isolates were found to show resistance to higher numbers of heavy metals than the non-hemolytic ones. Due to a possible health risk of these pathogenic bacteria, a need exists for an accurate assessment of their acquired resistance to multiple drugs and metals.
Sugarcane molasses-based bio-ethanol wastewater treatment by two-phase multi-staged up-flow anaerobic sludge blanket (UASB) combination with up-flow UASB and down-flow hanging sponge
Authors: Choeisai P. , Jitkam N. , Silapanoraset K. , Yubolsai C. , Yoochatchaval W. , Yamaguchi T. , Onodera T. , Syutsubo K.
Published: March 2014

This study was designed to evaluate a treatment system for high strength wastewater (vinasse) from a sugarcane molasses-based bio-ethanol plant in Thailand. A laboratory-scale two-phase treatment system composed of a sulfate reducing (SR) tank and multi-staged up-flow anaerobic sludge blanket (MS-UASB) reactor was used as the pre-treatment unit. Conventional UASB and down-flow hanging sponge (DHS) reactors were used as the post-treatment unit. The treatment system was operated for 300 days under ambient temperature conditions (24.6–29.6 °C). The hydraulic retention time (HRT) in each unit was kept at 25 h for the two-phase system and 23 h for the UASB&DHS. The influent concentration was allowed to reach up to 15,000 mg chemical oxygen demand (COD)/L. COD removal efficiency (based on influent COD) of the two-phase MS-UASB and the UASB&DHS was 54.9 and 18.7%, respectively. Due to the effective removal of sulfide in the SR tank, the MS-UASB achieved a high methane conversion ratio of up to 97%. In DHS, nitrification occurred at the outside portion of the sponge media while denitrification occurred at the inside. Consequently, 27% of the total nitrogen (TN) was removed. An amount of 32% of residual nitrogen (28 mgN/L) was in the form of nitrate, a better nitrogen state for fertilizer.
Modelling the erosive effects of sewer flushing using different sediment transport formulae
Authors: Shirazi R. H. S. M. , Campisano A. , Modica C. , Willems P.
Published: March 2014

A numerical investigation to simulate the cleaning effects of successive flushes over sediment beds in prismatic channels is presented in this paper. The 1D De Saint Venant-Exner equations were used to describe the temporal evolution of the sediment bed after each flush. The predictive capacity of two sediment transport formulae was explored against experimental results from laboratory tests. Results show that the adopted model can successfully describe the evolution of the sediment bed due to the flushes exerted during the experiments, with differences between the used transport formulae depending on the channel invert slope and on the flush energy.
A method for evaluating the evolution of clogging: application to the Pampulha Campus infiltration system (Brazil)
Authors: Barraud S. , Gonzalez-Merchan C. , Nascimento N. , Moura P. , Silva A.
Published: March 2014

In order to evaluate the hydraulic performance of stormwater infiltration trenches, a study was undertaken to assess clogging and its distribution between the bottom and the sides. The method used was based on the calibration of the hydraulic resistance event by event according to Bouwer's model and applied to a demonstration trench in Belo-Horizonte monitored in the framework of the European Project Switch. The calibration was performed by minimizing the distance between measured and modeled infiltration flow rates and by using continuous measurements of rainfall, inflow, water temperature and depth in the trench. The study showed that the methodology and particularly Bouwer's model was able to produce satisfactory results. It revealed a significant clogging evolution within a year, with global resistance increasing by a factor of 9. A significant difference between the bottom and the sides was observed; the bottom being more rapidly prone to clogging. Sudden fluctuations of the hydraulic resistance of the bottom were found that could be explained by very high concentrations of total suspended solids from inflows (about 2,000 mg/L). Clogging of the sides evolves over the time but with a very low rate.
Availability of different phosphorus forms in agricultural soil to Microcystis aeruginosa
Authors: Okubo Yoko , Inoue Takanobu , Yokota Kuriko , Ngoc Nguyen Minh
Published: March 2014

We investigated the availability of different forms of particulate soil phosphorus (P) to Microcystis aeruginosa by sequential extraction and bioassay. We cultured M. aeruginosa in media containing, as the sole source of P, soils sequentially extracted with 1 M NH4Cl, 0.11 M bicarbonate dithionite, 1 M NaOH, and 0.5 M HCl. Analyses of chlorophyll-a, particulate organic carbon, and particulate organic nitrogen showed that M. aeruginosa could utilize some of the P remaining in the soil after each extraction. Alkaline phosphatase (AP) assays of sequentially extracted soils showed distinct patterns that depended on the type of co-cultured soil. A direct relationship between cellular P concentrations and the level of alkaline phosphatase activity was observed in only some media, an indication that not all forms of P were equally suitable substrates for AP hydrolysis. These results imply that cyanobacterial-available P included not only HCl-extractable P, which is assumed to consist of carbonate or apatite bound-P and organic P, but also refractory P, which has been considered to be unavailable to algae. Both HCl-extracted P and refractory P enhance the production of chlorophyll a, but did not lead to the storage of P by M. aeruginosa.
Effect of anaerobic digestion at 35, 55 and 60 °C on pharmaceuticals and organic contaminants
Authors: Davidsson Å. , Kjerstadius H. , Haghighatafshar S. , Fick J. , Olsson M. , Wachtmeister H. , Eriksson E. , la Cour Jansen J.
Published: March 2014

The application of treated sewage sludge on farmland is a suggested method for recycling nutrients and reducing demand for commercial fertilizer. However, sludge needs to be safe from possible contaminants which can cause acute and long-term health and environmental problems. Residual pharmaceuticals and organic contaminants are mentioned as emerging threats since wastewater treatment plants are not designed to degrade these substances. The aim of this study was to screen and evaluate the presence, and reduction, of pharmaceuticals and polycyclic aromatic hydrocarbons (PAHs) during anaerobic digestion of mixed primary and waste-activated sludge at 35, 55 and 60 °C and during pasteurization at 70 °C. The study showed the difficulty of analysing pharmaceutical compounds in low concentrations in the sludge matrix. No general reduction of these compounds was seen during treatment, but for individual substances some reduction occured. The PAHs were generally not reduced during digestion or pasteurization, but for three substances (indeno[1,2,3-cd]pyrene and dibenzo[a,h]anthracene (analysed together) and benzo[g,h,i]perylene) reduction (up to 60%) during digestion was seen. Digestion at 35 and 55 °C resulted in about the same order of reduction of the three individual PAHs, which was higher than for digestion at 60 °C.
Biogas production from cheese whey wastewater: laboratory- and full-scale studies
Authors: Stamatelatou K. , Giantsiou N. , Diamantis V. , Alexandridis C. , Alexandridis A. , Aivasidis A.
Published: March 2014

A two-phase system for biogas production from cheese whey wastewater (CWW) was designed, set up and operated at laboratory and full scale for a whole cheese production season (8–9 months). The high efficiency and stability of the laboratory-scale system was demonstrated under various organic loading rates (OLRs) reaching 13 g chemical oxygen demand (COD) L−1d−1 and producing up to 9 L L−1d−1 of biogas (approximately 55% in methane). The COD removal was above 95% and the pH was maintained above 6.3 without any chemical addition. The full-scale system was operated at lower OLRs than its normal capacity, following the good response and high stability in disturbances of the laboratory-scale unit.
A novel approach to analyzing concentration polarization of polysaccharide solutions
Authors: Chang S. , Jamal S. , Chen H. , Zhou H. , Hong Y. , Adams N.
Published: March 2014

This paper describes a novel approach to analyzing the concentration polarization (CP) in the short-time constant flux filtration of polysaccharide solutions. With application of the pearl-necklace model based polymer solution permeability correlation, a transmembrane pressure (TMP) increase rate model was developed to relate the linear TMP increase rate measured in the short-time constant flux filtration to the solid concentration at the membrane surface, the polymer critical overlapping concentration, and the radius of gyration of the polymer molecules. Establishment of such a theoretical model allows analysis of the gelation propensity of the CP layer formed by polysaccharides based on the experimentally determined linear TMP increase rate.
Comparative effectiveness of transurethral resection of bladder tumors and office fulguration for recurrent bladder tumors
Authors: Karakiewicz Pierre I , Sun Maxine , Azizi Mounsif
Published: March 2014

Evaluation of: Park DS, Hwang JH, Gong IH
et al.
An analysis of the efficacy, safety, and cost–effectiveness of fulguration under local anesthesia for small-sized recurrent masses: a comparative analysis of transurethral resection of bladder tumors in a matched cohort.
J. Endourol.
27(10), 1240–1244 (2013).

At initial diagnosis, most bladder tumors are nonmuscle invasive. Some will recur after initial resection and will require transurethral resections of the bladder tumor. Fulguration under local anesthesia represents an alternative. This option is assessed in the article of Park
et al.
with respect to efficacy, safety and cost–effectiveness in patients with small-sized recurrent bladder tumors. The authors suggest that fulguration is safe and efficacious without compromising oncological outcomes in selected patients relative to formal transurethral resections of bladder tumor.
Interview: Patient-Centered Outcomes Research Institute seeks to find out what works best by involving ‘end-users’ from the beginning
Authors: Selby Joe V
Published: March 2014

Joe V Selby:
 A family physician, clinical epidemiologist and health services researcher, Dr Joe V Selby has more than 35 years of experience in patient care, research and administration. He is responsible for identifying strategic issues and opportunities for the Patient Centered Outcomes Research Institute (PCORI) and implementing and administering programs authorized by the PCORI Board of Governors. Dr Selby joined PCORI from Kaiser Permanente (CA, USA) where he was Director of the Division of Research for 13 years and oversaw a department of more than 50 investigators and 500 research staff members working on more than 250 ongoing studies. He was with Kaiser Permanente for 27 years. An accomplished researcher, Dr Selby has authored more than 200 peer-reviewed articles and continues to conduct research, primarily in the areas of diabetes outcomes and quality improvement. His publications cover a spectrum of topics, including effectiveness studies of colorectal cancer screening strategies; treatment effectiveness, population management and disparities in diabetes mellitus; primary care delivery; and quality measurement. Dr Selby was elected to membership in the Institute of Medicine in 2009 and was a member of the Agency for Healthcare Research and Quality study section for Health Care Quality and Effectiveness from 1999 to 2003. A native of Fulton (MI, USA), Dr Selby received his medical degree from Northwestern University (IL, USA) and his master’s in public health from the University of California (CA, USA). He was a commissioned officer in the Public Health Service Corps from 1976 to 1983 and received the Commissioned Officer’s Award in 1981.
Design of a cost–effectiveness analysis alongside a randomized trial of transplantation using umbilical cord blood versus HLA-haploidentical related bone marrow in advanced hematologic cancer
Authors: Roth Joshua A , Bensink Mark E , O’Donnell Paul V , Fuchs Ephraim J , Eapen Mary , Ramsey Scott D
Published: March 2014

Background:BMT CTN 1101 is a Phase III randomized controlled trial evaluating the comparative effectiveness of double unrelated umbilical cord blood (dUCB) versus HLA-haploidentical related donor bone marrow (haplo-BM) donor cell sources for blood or bone marrow transplantation (BMT) in patients with hematologic malignancies. Herein, we present the rationale, design and methods of the first cost–effectiveness analysis to be conducted alongside a BMT trial.Methods:Consenting patients will provide health insurance information to allow calculation of direct medical costs from reimbursement records, and will provide out-of-pocket costs, time costs and health-related quality of life measures through an online survey. These outcomes will inform a cost–effectiveness analysis comparing dUCB and haplo-BM donor cell sources from patient, payer and societal perspectives.Conclusion:Novel approaches may significantly change the cost, outcomes or availability of BMT. The results of this analysis will be the first to provide a comprehensive evaluation of the comparative effectiveness of these approaches from multiple perspectives.
Using comparative effectiveness research to remedy health disparities
Authors: Kupersmith Joel , LaBarca David
Published: March 2014

Health disparities are an important and continuing problem of considerable research importance. Comparative effectiveness research (CER) is an excellent vehicle to evaluate interventions to remedy disparities. We classify CER for disparities at three levels of science: basic biology, care and systems, and social and cultural context. In basic biology, genomics will delineate treatments for specific individuals and populations. Care and systems interventions are most important research areas to improve process and quality measures. However, there is evidence that correction of healthcare processes disparities will not be sufficient to improve health and that social and cultural research may be key in this regard. The methodology of CER for disparities is the same as that of other research with randomized controlled trials the gold standard and database analysis, and other observational and quasi-experimental methods important and effective. In addition, mixed methods and multilevel modeling offer promise. Community involvement in research and patient preferences among high-quality choices need to be included in planning of CER.
Big data, advanced analytics and the future of comparative effectiveness research
Authors: Berger Marc L , Doban Vitalii
Published: March 2014

The intense competition that accompanied the growth of internet-based companies ushered in the era of ‘big data’ characterized by major innovations in processing of very large amounts of data and the application of advanced analytics including data mining and machine learning. Healthcare is on the cusp of its own era of big data, catalyzed by the changing regulatory and competitive environments, fueled by growing adoption of electronic health records, as well as efforts to integrate medical claims, electronic health records and other novel data sources. Applying the lessons from big data pioneers will require healthcare and life science organizations to make investments in new hardware and software, as well as in individuals with different skills. For life science companies, this will impact the entire pharmaceutical value chain from early research to postcommercialization support. More generally, this will revolutionize comparative effectiveness research.
Computerized cognitive training interventions to improve neuropsychological outcomes: evidence and future directions
Authors: Howren M Bryant , Vander Weg Mark W , Wolinsky Fredric D
Published: March 2014

Age-related cognitive decline is common and may affect memory, orientation, attention, abstract thinking and perception, which may lead to substantial difficulties and disabilities in everyday life. Much evidence suggests that computerized cognitive training interventions may mitigate decline by improving neuropsychological outcomes in older adults, but there is clearly a need for large-scale, methodologically rigorous comparative effectiveness trials in the area. This article underscores that need and reviews eight trials that met a set of predetermined criteria before highlighting two novel and complementary analytic methods – big data analytics and network meta-analysis – that may be used to facilitate decisions regarding which cognitive training programs should serve as candidate interventions for large comparative effectiveness trials.
Density functional theory: 1H and 13C-NMR spectra of some coumarin derivatives
Authors: Spirtovic-Halilovic Selma , Salihovic Mirsada , Trifunovic Snezana , Roca Suncica , Veljovic Elma , Osmanovic Amar , Vinkovic Marijana , Zavrsnik Davorka
Published: March 2014

For some synthesized coumarin derivatives, 1H and 13C NMR isotropic chemical
shifts and some other molecular properties were calculated using density
functional theory. The calculations yield reliable results, that are in good
correlation with experimental data. This is a good basis for the
collaboration between experimentalists and quantum chemists.
Phylogenetic relationships among Porodaedalea pini from Poland and related Porodaedalea species
Authors: Szewczyk Wojciech , Kwaśna Hanna , Behnke-Borowczyk Jolanta , Baranowska-Wasilewska Marlena
Published: March 2014

Porodaedalea pini has been found to be a pathogen of Pinus banksiana (1 specimen) and Pinus sylvestris (39 specimens) in north-western Poland. This fungus was initially identified by its host preferences and morphological characters of sporophores and basidiospores. The ITS 1/2 rDNA region was sequenced and analysed using the neighbor-joining, maximum likelihood and maximum parsimony methods. All P. pini from Poland, P. pini neotype and other P. pini isolates from Europe grouped together forming a moderately supported monophyletic clade. The clade included two groups which did not correlate with geographic ranges. Nucleotide polymorphism of the Polish isolates of P. pini was small. This study provides evidence for the taxonomy of some isolates of the Porodaedalea Holarctic Group in North America: grouping with P. laricis or with P. gilbertsonii suggests that the isolates belong to these species. The absence of P. pini (in a form recognized in Europe) in North America is suggested. Sequencing of the ITS 1/2 rDNA region with the basidiomycete-specific primers (ITS1-F and ITS4-B) proved to be a suitable and sufficient method for differentiation of species within the genus Porodaedalea.
A multiplex real-time PCR assay for detection of oseltamivir-resistant strains of influenza virus
Authors: Nidzworski Dawid , Dobkowska Joanna , Hołysz Marcin , Gromadzka Beata , Szewczyk Bogusław
Published: March 2014

Influenza is a contagious disease of humans and animals caused by viruses belonging to the Orthomyxoviridae family. The influenza A virus genome consists of negative sense, single-stranded, segmented RNA. Influenza viruses are classified into subtypes based on two surface antigens known as hemagglutinin (H) and neuraminidase (N). The main problem with influenza A viruses infecting humans is drug resistance, which is caused by antigenic changes. A few antiviral drugs are available, but the most popular is the neuraminidase inhibitor — oseltamivir. The resistance against this drug has probably developed through antigenic drift by a point mutation in one amino acid at position 275 (H275Y). In order to prevent a possible influenza pandemic it is necessary to develop fast diagnostic tests. The aim of this project was to develop a new test for detection of influenza A virus and determination of oseltamivir resistance/sensitivity in humans. Detection and differentiation of oseltamivir resistance/sensitivity of influenza A virus was based on real-time PCR. This test contains two TaqMan probes, which work at different wavelengths. Application of techniques like multiplex real-time PCR has greatly enhanced the capability for surveillance and characterization of influenza viruses. After its potential validation, this test can be used for diagnosis before treatment.
Differentiated impact of procyanidins from evening primrose on human breast cancer cells
Authors: Lewandowska Urszula , Owczarek Katarzyna , Szewczyk Karolina , Sosnowska Dorota , Koziołkiewicz Maria , Hrabec Elżbieta
Published: March 2014

This study examines some of the biological activities of an evening primrose flavanol preparation (EPFP) against non-invasive human breast cancer cells (MCF-7). The results are compared with those obtained for highly invasive human breast cancer cells (MDAMB-231). The results show, for the first time, that EPFP reduces MCF-7 cell number, IC50 = 75 µM gallic acid equivalents/GAE for 72 h incubation, and reduces migration to 52% of the control value at 100 µM L−1 GAE. EPFP caused favorable changes in Bcl-2/Bax mRNA ratio, which rendered MCF-7 cells more sensitive to apoptosis: the number of apoptotic cells increased 2.2-fold vs. control at 100 µM GAE. Furthermore, 100 µ M L−1 GAE EPFP caused a 1.8-fold reduction in the activity of metalloproteinase-9 (MMP-9) secreted to the culture medium by MCF-7 cells. Moreover, EPFP suppressed the expression of selected genes of matrix metalloproteinases (MMPs), a proliferation marker (Ki67), and vascular endothelial growth factor (VEGF). In conclusion, the results of this study suggest that EPFP may exhibit proapoptotic, antiproliferative, antimigratory, and antimetastatic potential towards both selected human breast cancer cell lines, which is more pronounced in the case of the highly invasive MDA-MB-231 cells.
The Community College Route to the Bachelor’s Degree
Authors: Monaghan David B. , Attewell Paul
Published: March 2014

It is well established that students who begin post-secondary education at a community college are less likely to earn a bachelor’s degree than otherwise similar undergraduates who begin at a 4-year school, but there is less consensus over the mechanisms generating this disparity. We explore these using national longitudinal transcript data and propensity-score methods. Inferior academic preparation does not seem to be the main culprit: We find few differences between students’ academic progress at each type of institution during the first 2 years of college and (contrary to some earlier scholarship) students who do transfer have BA graduation rates equal to similar students who begin at 4-year colleges. However, after 2 years, credit accumulation diverges in the two kinds of institutions, due in part to community college students’ greater involvement in employment, and a higher likelihood of stopping out of college, after controlling for their academic performance. Contrary to some earlier claims, we find that a vocational emphasis in community college is not a major factor behind the disparity. One important mechanism is the widespread loss of credits that occurs after undergraduates transfer from a community college to a 4-year institution; the greater the loss, the lower the chances of completing a BA. However, earlier claims that community college students receive lower aid levels after transfer and that transfers disproportionately fail to survive through the senior year are not supported by our analyses.
Time to Pay Up
Authors: Rice Jennifer King , Malen Betty , Jackson Cara , Hoyer Kathleen Mulvaney
Published: March 2014

The effectiveness of educator incentive programs rests on the assumption that the potential rewards for participants will motivate them to behave in certain ways (e.g., choose certain jobs, expend greater effort, engage in capacity-building professional development). Some researchers have examined the impact of financial incentives on teacher behaviors and work conditions, but few look inside schools to examine how current teachers interpret their rewards, how payouts affect teachers’ willingness to participate in these programs, and how incentives might be structured to motivate teachers. This mixed-methods study of one Teacher Incentive Fund–supported program addresses that gap. We draw on expectancy and goal setting theories to analyze teachers’ reactions to financial rewards and how their reactions may shape the motivational potency of the incentives.
USE OF MOSSES FOR THE SURVEY OF HEAVY METAL DEPOSITION IN AMBIENT AIR OF THE KATHMANDU VALLEY APPLYING ACTIVE MONITORING TECHNIQUE
Authors: Shakya Kumudini , Chettri Mukesh K. , Sawidis Thomas
Published: March 2014

To understand the level of heavy metals (Cd, Co, Cr, Cu, Pb, Mn, Ni and Zn) in the ambient air of the Kathmandu valley, active monitoring technique using mosses was performed. Common mosses like Taxiphyllum giraldii (C. Muell.) Fleisch., Thuidium sparsifolium (Mitt.) Jaeg., and the leafy liverwort Ptychanthus striatus (Lehm. & Linderb.) Nees. collected from Phulchowki (a clean natural area) were transplanted at 25 different sites of the valley and were exposed for 3 months. These sites were broadly divided into 3 categories on the basis of vehicular traffic: inside Ring Road (high traffic), along Ring Road (high to moderate traffic) and outside the Ring Road (moderate to lax traffic). Three sites - Shivapuri (North-east), Raniban (North-west) and Phulchowki (South-east) were considered as control sites. Contamination Factor (CF) value obtained from the heavy metal concentration in exposed mosses indicated high contaminated sites mostly along and inside the ring road (except Zn which was found to be higher outside the ring road). On the basis of the average concentrations of the elements in the transplanted mosses, a general picture of air quality of the studied area has been ascertained. From this study, it can be made certain that ambient air of the Kathmandu valley is severely contaminated with Pb, Cr and Zn and relatively low with Co, Cu, Mn and Ni. DOI: http://dx.doi.org/10.3126/eco.v19i0.9850EcoprintAn International Journal of EcologyVol. 19, 2012Page: 17-29Uploaded date: 2/14/2014
ASSESSMENT OF DIFFERENT NON-HOST CROPS AS TRAP CROP FOR REDUCING OROBANCHE AEGYPTIACA PERS. SEED BANK
Authors: Acharya Bipana Devi
Published: March 2014

Experiments were performed in pot and field conditions to evaluate effects of non-host crops on Orobanche seed bank. The two sites chosen for the study were located in highly Orobanche infested areas of Nawalparasi district, an inner Terai region of central Nepal. Pot and field experiments were conducted in the soil naturally infested with Orobanche seeds. Altogether, 21 different non-host crop species were tested in the study. Orobanche seed density in soil samples collected from pot/plot before planting and after harvest of each crop species was recorded. Data of pre-plant and postharvest were compared in order to assess the effects of the test crops on Orobanche seed density. On the basis of degree of effects on the Orobanche seed bank, the investigated crop species could be classified in to three categories: (a) non-potential trap crop: garlic, chilli, coriander, carrot, buckwheat, sunflower, french bean, pea, egg plant, potato, fenugreek, wheat and faba bean; (b) moderately potential trap crop: barley, onion, chickpea and maize; and (c) highly potential trap crops: radish, lentil, linseed, fennel and cumin.DOI: http://dx.doi.org/10.3126/eco.v19i0.9851EcoprintAn International Journal of EcologyVol. 19, 2012Page: 31-38Uploaded date: 2/14/2014
BIOMASS AND PRODUCTIVITY OF WEEDS IN A FALLOW PERIOD AT GUJAR TAL MARGIN
Authors: Singh Mayank , Singh O. P. , Singh M. P.
Published: March 2014

This paper deals with biomass accumulation and net primary productivity pattern in a fallow period of a lake margin agroecosystem. The slight slopping margin of present study site was characterized into two ecological zones, i.e. upper and lower from top up-land to lower region near water margin. Maximum biomass of dominant weed Cynodon dactylon (Linn.) Pers. and ‘rest weeds’ were 190.55 and 265.22 g m-2 in upper zone in September. In contrast, in the lower zone of study site peak value of biomass of dominant plant C. dactylon and ‘rest weeds’ were 67.91 and 178.84 g m-2, respectively in June as lower zone was inundated from fist fortnight of July to September, 2008. The Maximum percentage contribution of dominant weed (C. dactylon) was 54.00 and 59.15% in March and ‘rest weeds’ was 74.49 and 75.15% in April, 2008 in the respective upper and lower zones. Maximum productivity values of respective dominant weed (C. dactylon) and ‘rest weeds’ in upper zone were 2.07 and 2.51 g m-2 day-1 in July. In contrast, in the lower zone of the study site the peak productivity values of respective dominant weed (C. dactylon) and ‘rest weeds’ were observed 1.36 in June and 1.23 g m-2 day-1 in October. Total productivity values in two respective zones upper and lower have varied 330.59 and 140.17 g m-2 per eight month. Analysis of variance in standing biomass of plant species was found significant (p<0.05 in upper zone and p<0.01 in lower zone). DOI: http://dx.doi.org/10.3126/eco.v19i0.9858Ecoprint An International Journal of Ecology Vol. 19, 2012 Page: 85-90 Uploaded date: 2/14/2014
Researches on the Nepalese mycoflora - 2, Checklist of Macrofungi (Mushrooms) Book Review
Authors: Tiwari R. D.
Published: March 2014

Not available (Book review)DOI: http://dx.doi.org/10.3126/eco.v19i0.9859Ecoprint An International Journal of Ecology Vol. 19, 2012 Page: 91-91 Uploaded date: 2/14/2014
Quality of Life of Patients undergong Haemodialysis at B.P. Koirala Institute of Health Sciences
Authors: Anu VK , Pushpa Parajuli , Kumar Sharma Sanjib
Published: March 2014

DOI: http://dx.doi.org/10.3126/jmmihs.v1i2.9904 Journal of Manmohan Memorial Institute of Health Sciences Vol.1(2) 2013; 19-25
Effect of TiO2 in aluminum matrix on workability behavior of powder metallurgy composites during cold upsetting
Authors: Ravichandran M. , Sait A. Naveen , Anandakrishnan V.
Published: March 2014

Aluminum-based metal matrix composites with various weight percentages (0, 2.5, 5, 7.5, and 10) of TiO2 reinforcement were synthesized by means of powder metallurgy and their workability behavior under triaxial stress-state conditions was completely studied during cold upsetting. Green cylindrical compacts were made using a 400 kN hydraulic press with suitable punch and die, sintered at (590 ± 10) °C for a period of 3 h, furnace cooled and machined to obtain samples with 0.5 aspect ratio. The cold upset tests were carried out in steps of 10 kN and the results were studied for the workability behavior of the composites. The formability stress index (β) and stress ratio parameters (σz/σeff), (σm/σeff), and (σθ/σeff) were calculated for all composites and correlated with true axial strain (∊
z
). It was observed that the addition of TiO2 to the Al matrix material increases the stress ratio parameters and formability stress index (β).
Evaluation of corrosion performance of two Mn-containing stainless steel alloys
Authors: Toor Ihsan-ul-Haq
Published: March 2014

300 series austenitic stainless steels (SSs) are widely used as structural materials in various corrosive environments because of their excellent corrosion resistance and good mechanical properties. However, due to the rapid increase in Ni cost over the last few years, there have been attempts to develop cheap SSs while still maintaining their relatively high corrosion resistance. The possible replacements for Ni (a gamma stabilizer) in SSs are Mn, N and Cu etc. In this paper, the effect of Mn addition on the corrosion properties of two SS alloys, i. e. 202M2 and 202M4, is discussed and results are compared with those of 304 SS alloy. Results of different tests showed that overall corrosion resistance properties (measured in terms of pitting potential (E
pit), metastable pitting events density and time to failure etc.) decreased with an increase in Mn content of the alloys.
Dielectric and magnetic properties of Ba0.8Sr0.2TiO3 – Y3Fe5O12 – YFeO3 composites
Authors: Yang Yanyan , Yang Haibo , Lin Ying , Liu Miao
Published: March 2014

Ba0.8Sr0.2TiO3 – Y3Fe5O12 – YFeO3 (BST-YIG-YIP) composites were prepared via the in-situ growth solid-state method. The composites were obtained by sintering green bodies composed of Ba0.8Sr0.2TiO3 and Y3Fe5O12 powders at 1 350 °C. The phase composition and microstructure of the composites were analyzed. The dielectric and magnetic properties of the composites were also investigated. The results show that the as-prepared BST-YIG-YIP composites have large dielectric constants, high permeabilities and high saturation magnetizations.
Effects of rolling rate on microstructure and mechanical properties of Mg sheets
Authors: Dai Qingwei , Zhang Dingfei , Lan Wei , Chen Xi , Chen Qichuan , Bai Delei
Published: March 2014

This study investigates the effects of rolling rate on the microstructure and mechanical properties of magnesium alloy sheets. AZ31 plates were rolled at speeds of 5, 10, 20 and 30 r · min−1 at room temperature. Optical microscopy, micro-hardness testing, and X-ray diffraction were carried out to characterize the material microstructure. Results show that the number of twin grains increases as the rolling rate increases. Simultaneously, the micro-hardness of the samples decreases, and the (0 001) basal texture is weakened. These results suggest the use of high rolling speed to practically reduce the formation of unfavorable basal texture in manufacturing magnesium alloy sheets.
Carbon dioxide flux in the ablation area of Koxkar glacier, western Tien Shan, China
Authors: Wang Jian , Han Haidong , Zhang Shiqiang
Published: March 2014

Accelerating loss of glacial mass caused by rising global temperatures has significant implications. The global cycle of the greenhouse gas CO2 is also associated with mineral weathering and glaciation. In glaciated areas, most estimates of atmospheric CO2 consumption are confined to chemical ionic mass balance or analog modeling methods. We applied the gradient method to the surface of Koxkar glacier, western Tien Shan, China, for a 5 month period during 2012. The overall net glacier-system CO2 exchange (NGE) rate was measured as -0.05 and -0.07mmol m–2 s–1 for regions of exposed ice and supraglacial moraine, respectively. This suggests that atmospheric CO2 drawdown may occur during ice melting because of consumption of H+ by CO2 hydrolysis that occurs in solutions. Using the degree-day model to calculate glacier ablation in bare-ice regions and considering characteristics of the NGE rate in the supraglacial debris region with the support of GIS, the daily NGE rate was estimated to be -1.23 ± 0.17μmmol m–2 d–1 between Julian days 125 and 268 of 2012. These findings present a new approach for modeling the dynamics of glacial CO2 sinks undergoing melting, and develop an understanding of the mechanism of atmospheric CO2 exchange.
Investigation of the correlation between microstructure and hysteresis curve of li0.5-x/2cuxfe2.5-x/2o4 ferrites
Authors: Ullah M Samir , Hoque S Manjura , Khan FA
Published: March 2014

Cu substituted lithium ferrites with composition Li0.5-x/2CuxFe2.5-x/2O4 (where x = 0.0, 0.1, 0.2, 0.4 and 0.6) were synthesized by conventional double sintering ceramic technique and sintered at 1100oC for 3 hours in the normal atmosphere. The microstructures for the samples of different compositions were examined by scanning electron microscope (SEM). The average grain size was determined by the linear intercept method which demonstrates that the average grain size increases with the increase of Cu content. The initial permeability was found to increase with Cu content, x, which is attributed to increase of grain size of the samples. The parameters of hysteresis curve have been determined at room temperature by B-H Loop Tracer. It was found that coercivity and initial permeability were closely related to each other which are mainly governed by the anisotropy and grain size of the mixed ferrites. DOI: http://dx.doi.org/10.3329/jbas.v37i2.17551 Journal of Bangladesh Academy of Sciences, Vol. 37, No. 2, 121-129, 2013
Bioengineering approach for sewage sludge degradation through aerobic thermophilic process
Authors: Naik Bijaya Nanda , Masih Harison , Singh Ajaya
Published: March 2014

The aerobic thermophilic sewage sludge treatment process was studied at various bioreactor scales through modified bioengineering design approach. The effectiveness of the biological system was controlled by varying the process operating conditions of bioreactor to enhance microbial degradation efficiency. The inactivation of pathogen each promoted by increase of temperature, while the residual CFU was lowered by reducing the total solids content of sewage sludge. The optimum sludge degradation through aerobic thermophilic process occurred in temperature range of 58 - 62oC but temperature more than 60oC was suitable for hygienic inactivation. Dual digestion systems of an aerobic theromophilic treatment followed by anaerobic thermophilic stabilization stage shows greater treatment and efficiency in degrading the organic sludge constituting up to seventy per cent. DOI: http://dx.doi.org/10.3329/jbas.v37i2.17556 Journal of Bangladesh Academy of Sciences, Vol. 37, No. 2, 159-163, 2013
Preparation and characterization of iron(iii) complex of saccharin
Authors: Tanvir Taj Al , Hossain Md Elius , Mamun Mohammad Al , Ehsan MQ
Published: March 2014

Complex of iron(III) with saccharin, [Fe(C7H4O3SN)2Cl] has been prepared in aqueous medium. The IR and electronic spectral analysis suggest that two saccharin molecules are attached to the metal ion through N atom and there is no chemically coordinated or crystalline water in the complex molecule. The magnetic moment value indicates the paramagnetic character of the complex. The cyclic voltammetric study indicates a quasi-reversible electron transfer process due to the presence of iron in the compound. DOI: http://dx.doi.org/10.3329/jbas.v37i2.17560 Journal of Bangladesh Academy of Sciences, Vol. 37, No. 2, 195-203, 2013
Sleep, Plasticity and the Pathophysiology of Neurodevelopmental Disorders: The Potential Roles of Protein Synthesis and Other Cellular Processes
Authors: Picchioni Dante , Reith R. , Nadel Jeffrey , Smith Carolyn
Published: March 2014

Sleep is important for neural plasticity, and plasticity underlies sleep-dependent memory consolidation. It is widely appreciated that protein synthesis plays an essential role in neural plasticity. Studies of sleep-dependent memory and sleep-dependent plasticity have begun to examine alterations in these functions in populations with neurological and psychiatric disorders. Such an approach acknowledges that disordered sleep may have functional consequences during wakefulness. Although neurodevelopmental disorders are not considered to be sleep disorders per se, recent data has revealed that sleep abnormalities are among the most prevalent and common symptoms and may contribute to the progression of these disorders. The main goal of this review is to highlight the role of disordered sleep in the pathology of neurodevelopmental disorders and to examine some potential mechanisms by which sleep-dependent plasticity may be altered. We will also briefly attempt to extend the same logic to the other end of the developmental spectrum and describe a potential role of disordered sleep in the pathology of neurodegenerative diseases. We conclude by discussing ongoing studies that might provide a more integrative approach to the study of sleep, plasticity, and neurodevelopmental disorders.
Recent Progress in the Definition of Thermodynamic Entropy
Authors: Zanchini Enzo , Beretta Gian
Published: March 2014

The principal methods for the definition of thermodynamic entropy are discussed with special reference to those developed by Carathéodory, the Keenan School, Lieb and Yngvason, and the present authors. An improvement of the latter method is then presented. Seven basic axioms are employed: three Postulates, which are considered as having a quite general validity, and four Assumptions, which identify the domains of validity of the definitions of energy (Assumption 1) and entropy (Assumptions 2, 3, 4). The domain of validity of the present definition of entropy is not restricted to stable equilibrium states. For collections of simple systems, it coincides with that of the proof of existence and uniqueness of an entropy function which characterizes the relation of adiabatic accessibility proposed by Lieb and Yngvason. However, our treatment does not require the formation of scaled copies so that it applies not only to collections of simple systems, but also to systems contained in electric or magnetic fields and to small and few-particle systems.
Germanium Based Field-Effect Transistors: Challenges and Opportunities
Authors: Goley Patrick , Hudait Mantu
Published: March 2014

The performance of strained silicon (Si) as the channel material for today’s metal-oxide-semiconductor field-effect transistors may be reaching a plateau. New channel materials with high carrier mobility are being investigated as alternatives and have the potential to unlock an era of ultra-low-power and high-speed microelectronic devices. Chief among these new materials is germanium (Ge). This work reviews the two major remaining challenges that Ge based devices must overcome if they are to replace Si as the channel material, namely, heterogeneous integration of Ge on Si substrates, and developing a suitable gate stack. Next, Ge is compared to compound III-V materials in terms of p-channel device performance to review how it became the first choice for PMOS devices. Different Ge device architectures, including surface channel and quantum well configurations, are reviewed. Finally, state-of-the-art Ge device results and future prospects are also discussed.