bluuebunny/crossref_metadata_2025 huggingface dataset:
Combining Ability and Genetic Diversity of Extra‐Early White Maize Inbreds under Stress and Nonstress Environments
Authors: Badu‐Apraku B. , Oyekunle M. , Akinwale R. O. , Aderounmu M.
Published: February 2014

Maize (Zea mays L.) has the greatest yield potential in savannas of West and Central Africa (WCA). However, production in this agroecology is constrained by low levels of N, drought, and parasitism by striga [Striga hermonthica (Del) Benth.]. Diallel crosses involving 17 extra‐early white maize inbreds were evaluated under drought, striga, and optimal environments at three locations in Nigeria for 2 yr. The objectives of this study were to estimate general and specific combining ability for grain yield, classify the inbreds into heterotic groups, and identify inbred testers. Gene action controlling grain yield and most other traits was predominantly nonadditive. TZEEI 14, TZEEI 29, TZEEI 21, and TZEI 13 were the best testers across environments. Four heterotic groups were identified based on the heterotic group's specific and general combining ability (HSGCA) method and five groups based on microsatellite markers. TZEEI 29 × TZEEI 14 was the second highest yielding and most stable across environments. Fifty‐nine alleles with an average of 2.57 alleles per locus were detected among the inbreds. Correlation between genetic distance estimates of parental lines and their F1 hybrid means were not significant for grain yield and most other traits. There was close correspondence between heterotic groups identified by the HSGCA method and microsatellite markers. Extra‐early inbreds and hybrids with drought tolerance and striga resistance genes identified should be used to reduce instability of maize yields in WCA.
The Effect of Ohmic Cable Losses on Time‐Domain Reflectometry Measurements of Electrical Conductivity
Authors: Castiglione P. , Shouse P. J.
Published: February 2014

In time domain reflectometry (TDR), the ohmic resistance of the sample medium is related to the amplitude of the reflected signal at long time, once all the multiple reflections have taken place and steady state is achieved. Such a relationship, which permits measuring the sample electrical conductivity, is exact when no signal dissipation occurs other than in the sample. To account for signal attenuation along the coaxial cable, sample and cable are generally modeled as two resistors in series. In this work we review the fundamentals of the transmission line theory and demonstrate, both theoretically and experimentally, that such a formulation is incorrect. We propose a new simple procedure for the analysis of TDR signals based on a difference reflection method, by scaling the reflection coefficients with respect to one or more standards of known conductivity. The procedure was tested on 16 CaCl2 solutions, using two different TDR probes and two cable lengths. The experimental results are in excellent agreement with the theory.
Dissolved Phosphorus from Undisturbed Soil Cores
Authors: Akhtar M. Saleem , Richards Brian K. , Medrano Pedro A. , deGroot Maarten , Steenhuis Tammo S.
Published: February 2014

While the rapid transport of nonadsorbed chemicals is relatively well understood, preferential transport of adsorbable chemicals including P requires further study. Our objective was to characterize subsurface P transport in glaciated soils of the northeastern USA. Large intact columns from five soils with differing structures were subjected in duplicate to both synthetic acid rainfall at a low rate simulating natural rainfall, and ponded water for observing saturated flow. The rain was enriched with inorganic and organic P after baseline conditions were established. Drainage water P concentrations were measured and adsorption isotherms were determined. Type of flow was characterized using Cl breakthrough curves and visualizations of blue dye patterns. Baseline P concentrations in drainage water were 0.02 to 0.04 mg L−1 At low flow rates, P appeared in the drainage water soon after application of either inorganic or organic P for the silt loam soil (firm, moderate coarse prismatic parting to moderate medium subangular blocky structure) in which preferential flow paths carried most of the water flow. In contrast, the soils in which matrix type flow dominated (weak fine granular or weak medium subangular blocky structures) had little or no increase in drainage water P. However, under ponded conditions all soils exhibited preferential flow and rapid P breakthrough. Elevated P concentration in the drainage water could not be explained by the P adsorption strength with the possible exception of the sandy loam soil, where the outflow P concentration was consistently low. Variation in flow rate in conjunction with soil structure satisfactorily explained elevated concentrations of dissolved inorganic and organic P in drainage water from surface applied P.
Changes in Composition of Nitrogen‐15‐Labeled Gases during Storage in Septum‐Capped Vials
Authors: Laughlin Ronald J. , Stevens R. James
Published: February 2014

We tested the reliability of 12‐mL Exetainers (Labco Ltd., High Wycombe, UK) fitted with bromobutyl rubber septa for the storage of a gas sample containing15N‐labeled N2O and N2The gas mixture was analyzed monthly over a 1‐yr storage period by continuous‐flow isotope‐ratio mass spectrometry (IRMS). After a year the N2O concentration had decreased by 30% but the change in15N enrichment of N2O was not detectable. Accurate determination of the N2O concentration was possible up to 1 yr if a calibration gas was stored and analyzed along with the test mixture. This technique has wide applicability because diffusive loss of N2O as a fraction of starting concentration was predicted by Fick's Law to be almost independent of concentration above 3 μL L−1The rate of decrease in the enrichment of N2as measured by the ratio differences for 29/28 and 30/28 was slow. Decreases were not significantly different from time zero values after storage for 8 wk. After 1 yr of storage the losses of29N2and30N2significantly lowered the calculated value for the fraction of the N2from the labeled pool (d) by about 2% of the initial value, but had no effect on the calculated value for the enrichment of the labeled pool (15XN). The diffusivity of N2O, calculated from loss rate and concentration gradient between Exetainer and atmosphere using Fick's Law, was 40 times higher than that of29N2or30N2Nitrous oxide may have been lost from the Exetainer because of adsorption by the septum as well as diffusion through the septum.
Infiltration and Erosion in Soils Treated with Dry PAM and Gypsum
Authors: Yu Jian , Lei T. , Shainberg I. , Mamedov A. I. , Levy G. J.
Published: February 2014

Seals formed at the soil surface during rainstorms reduce rain infiltration and cause runoff and erosion. Surface application of anionic polyacrylamide (PAM) in solution has been found to be very effective in decreasing seal formation, runoff, and erosion. The objective of this study was to investigate the effect of surface application of granular PAM (10 and 20 kg ha−1) and gypsum (2 and 4 Mg ha−1) on the infiltration rate (IR) and soil erosion from a silty loam (Calcic Haploxeralf) and sandy clay (Typic Chromoxerert) during simulated distilled water rainstorms. Mixing dry PAM with the upper 5 mm of the soil surface reduced slightly the IRs, and reduced significantly soil erosion from the two soils. Spreading gypsum at the soil surface doubled the final IR compared with that of control and reduced erosion slightly. Spreading dry PAM mixed with gypsum was very effective in increasing the rain IR and reducing erosion. Mixture of 20 kg ha−1PAM and 4 Mg ha−1gypsum increased the final IR of the two soils by four times and reduced erosion to 30% that of the control. Gypsum added to the erosion benefits of PAM by increasing infiltration and decreasing runoff. However, mixing gypsum with dry PAM decreased the beneficial effect of PAM in reducing erosion in the silty loam soil. The mechanisms responsible for the specific effects of PAM (mixed with soil and gypsum) on rain infiltration and soil losses are discussed.
Changes in Soil Phosphorus from Manure Application
Authors: Griffin T. S. , Honeycutt C. W. , He Z.
Published: February 2014

Manure and mineral fertilizer P sources vary in their contributions to soil P pools. We conducted incubation experiments to (i) assess temporal changes in soil P concentration for 84 d following application of KH2PO4 or manure (beef, dairy, poultry, or swine), and (ii) to evaluate interactive effects of P rate, P source, and background P level on soil P pools 90 d after P application. Changes in soil P over time were evaluated following the amendment of a coarse‐loamy, mixed, frigid Typic Haplorthod soil (pH 5.8) at a rate of 100 mg total P kg−1 Water soluble P (WSP), 0.01 M CaCl2–extractable P (CaCl2–P), and modified Morgan P (MMP) declined to <3 mg P kg−1 soil within 21 d of application, following an exponential decay function; P extracted by anion‐exchange membrane (AEMP) and Mehlich‐III (M3‐P) also declined rapidly and are attributed to the high level of exchangeable Al and Fe in this soil. Ninety days after application, all soil P pools exhibited linear increases in concentration for application rates up to 800 mg P kg−1 soil, regardless of P source. Phosphorus applied as KH2PO4 was more efficient at increasing CaCl2–P and M‐3P. Manure P sources generally had a greater effect on MMP, and poultry manure was more efficient than all other sources. Efficiency of P sources at increasing soil P concentration (b, slope of linear regression) varied from <1% for rapidly available P pools (CaCl2–P) to nearly 50% for more recalcitrant P (M3‐P). Efficiency also increased as background M3‐P increased from 150 to 750 mg kg−1 soil. The amount of CaCl2–extractable P increased rapidly when soil P saturation ([Mehlich III‐P]/[Mehlich‐III Al + Fe]) exceeded 0.25 mol mol−1 Manure and KH2PO4 contribute to different soil P pools, and these differences are magnified at high application rates and high background soil P levels.
Dissolution of Ripidolite (Mg, Fe‐Chlorite) in Organic and Inorganic Acid Solutions
Authors: Hamer M. , Graham R. C. , Amrhein C. , Bozhilov K. N.
Published: February 2014

Although chlorites are an important source of Mg and micronutrients in soils, little is known about their weathering behavior in acidic environments. The effect of organic (acetic, oxalic, citric) and inorganic (hydrochloric, nitric, sulfuric) acids on the dissolution of ripidolite was studied at 25°C over an acid concentration range of 0.03 to 10 mM The increasing ripidolite dissolution with increasing acid concentration can be described by the same empirical equation for all six acids used in this study. Because proton and ligand promoted dissolution mechanisms are additive, the influence of ligands can be calculated by subtracting the influence of protons from the total dissolution of ripidolite. We assume that the influence of Cl− in HCl systems can be neglected. Greater dissolution of ripidolite in the presence of the other acids at the same pH is attributed to the accompanying anion. At pH 3.5 and an anion concentration of 10−3.5 mol L−1, the relative effectiveness of the acids used in this experiment in promoting dissolution was nitric (enhancement factor: 0.97) ≅ hydrochloric (1.00) ≅ acetic (1.01) < sulfuric (1.19) < citric (2.70) < oxalic acid (3.27). The dissolution of ripidolite was nonstoichiometric with a preferential release of Si relative to Al, Fe, and, in some cases, Mg at low proton and ligand concentrations for all six acids. At higher acid concentrations the dissolution becomes almost stoichiometric in the presence of inorganic acids, whereas in the presence of oxalic acid Al, Fe, and Mg were released preferentially relative to Si. In the presence of citric acid, Fe is released preferentially relative to Si. The alteration of chlorites in soils and the amount of released elements into the soil solution therefore depends on the composition of acidifying agents in soils.
A novel acoustic imaging tool for monitoring the state of rapid sand filters
Authors: Allouche Nihed , Simons Dick G. , Keijzer Paul , Rietveld Luuk C. , Kappelhof Joost
Published: February 2014

A new technology based on acoustic waves is developed to monitor the state of sand filters used in drinking water treatment. Changes in the sand filter, due to the removal of suspended particles from the water and their accumulation in the pores, result in an increase of the bulk density and acoustic speed of the granular material. Consequently, the reflected acoustic response changes as the filter is in use. To monitor these changes, an instrument composed of an omnidirectional transmitter and an array of hydrophones was built. With frequencies ranging between 10 and 110 kHz, high resolution is achieved in the vertical direction enabling the detectability of clogged layers with a minimum thickness of 1 cm. The novel instrument is tested by conducting a monitoring experiment in a filter used in practice. A 2D scan over a part of the filter was performed and repeated every 2 hours over a period of 10 days. An analysis of the data revealed a local increase of the reflected acoustic response with increasing filter run time. The changes in acoustic signal are mainly observed at the upper 5 cm of the sand bed. It is also clear that the filter bed is slowly compacting as a function of time. The total compaction after a period of 10 days reached 3.5 cm. The filter bed is expanded again during the cleaning procedure. Once the procedure is completed, the upper 30 cm of the filter becomes more transparent, showing small accumulations of material at greater depth. The observed changes in the filter bed demonstrate the potential of this acoustic-based tool to monitor the state of rapid sand filters and optimise their performance. The new tool can be used to evaluate the cleaning procedure and is valuable in detecting lateral variations in the filter bed. These variations may indicate local clogging that needs to be removed effectively to avoid deterioration of the overall performance in the long term. This type of information is difficult to obtain from the monitoring techniques currently used in drinking water treatment.
Modelling both the continual erosion and regeneration of discolouration material in drinking water distribution systems
Authors: Furnass W. R. , Collins R. P. , Husband P. S. , Sharpe R. L. , Mounce S. R. , Boxall J. B.
Published: February 2014

The erosion of the cohesive layers of particulate matter that causes discolouration in water distribution system mains has previously been modelled using the Prediction of Discolouration in Distribution Systems (PODDS) model. When first proposed, PODDS featured an unvalidated means by which material regeneration on pipe walls could be simulated. Field and laboratory studies of material regeneration have yielded data that suggest that the PODDS formulations incorrectly model these processes. A new model is proposed to overcome this shortcoming. It tracks the relative amount of discolouration material that is bound to the pipe wall over time at each of a number of shear strengths. The model formulations and a mass transport model have been encoded as software, which has been used to verify the model's constructs and undertake sensitivity analyses. The new formulations for regeneration are conceptually consistent with field and laboratory observed data and have potential value in the proactive management of water distribution systems, such as evaluating change in discolouration risk and planning timely interventions.
Removal of DOM and AOC in a full-scale advanced water treatment plant: effects of operational periods of BAC filters
Authors: Lohwacharin J. , Yang Y. , Watanabe N. , Phetrak A. , Takizawa S.
Published: February 2014

Water utilities in Japan want to reduce residual chlorine levels so as to reduce disinfection byproducts and the chlorine smell, but bacterial regrowth is a concern. In advanced water treatment plants using ozonation and biological activated carbon (BAC), BAC plays the most important role in reducing assimilable organic carbon (AOC). Therefore, we analyzed the removal of dissolved organic matter (DOM) and AOC by full-scale BAC filters with different operational periods. Seasonal variation in AOC in raw water was wide, with a maximum of 306 μg acetate-C/L in November, and ozonation increased AOC. Nonetheless, BAC filters that had operated for 6 years produced water with lower AOC than ones with shorter operational periods, although they released a small amount of aromatic DOM. A diagram was constructed to derive the required levels of residual chlorine for no bacterial regrowth at various AOC levels of BAC effluents, which were linked with the operational periods of BAC filters and AOC in the ozonation effluents. Although BAC filters operated for longer than 100 weeks can effectively reduce AOC, lowering AOC levels in the ozonation effluent was indispensable for preventing bacterial regrowth in the water supply network at lower levels of residual chlorine than at present.
Somaclonal variation of sugar beet resistant to pathogenic root rot Fusarium oxysporum var. orthoceras
Authors: Urazaliev Kairat , Abekova Alfiya , Bazylova Tamara , Bersimbaeva Gulnara , Daniyarova Aliya , Massonichich-Shotunova Raushan
Published: February 2014

Sugar beet (Beta vulgaris L.) - one of the most important crop in the world.
In Kazakhstan, it is a traditional and major source of domestic sugar. The
industry of cultivation and production of sugar beet is one of the priority
areas of agricultural development of the country. In this paper, we studied
the regeneration ability of different genotypes of sugar beet explants on
selective media with the culture filtrate of the pathogen fungus F. oxysporum
var. orthoceras. From the roots and shoots of sugar beet the pathogen
Fusarium root rot was isolated. Was obtained pure cultures of the isolated
pathogen. As a result, of morphological and cultural descriptions, as well as
microbiological analysis it was revealed that the isolated pathogen is
Fusarium Oxysporum. The results showed the pathogenicity of the fungus. For
regeneration in vitro of the sugar beet genotypes resistant to the pathogen
the culture media was optimized to the culture filtrate of the fungus F.
oxysporum var. orthoceras. The frequency of shoot regeneration, depending on
the genotype, was 1,0-12,5 %. On these explants the multiple shoot formations
were observed.
Genetic variability and divergence analyses in Jatropha curcas based on floral and yield traits
Authors: Maurya Ramanuj , Verma Saurabh , Gupta Astha , Singh Bajrang , Yadav Hemant
Published: February 2014

Genetic variability of 80 accessions of Jatropha curcas showed that oil
content varied between 20.8-36.1% (X=26.2?0.38). Thirty seven accessions
showed seed weight/plant above average mean value (180.2g) and 26 accessions
showed oil content above average mean (26.2%). The hierarchical clustering
grouped all the accessions into 4 clusters. Clustering showed that majority
of accessions i.e. 56 (70%) were genetically close to each other and grouped
in two clusters. The maximum intra cluster distance was recorded in cluster
IV (30.15). The inter cluster distance varied from 47.59 (between cluster I
and cluster II) to 211.27 (between cluster III and cluster I). The cluster
III showed maximum genetic distance with cluster I, followed by cluster IV
and cluster II suggesting comparatively wider genetic diversity among them.
The Principal Component Analysis (PCA) showed that first four principal
components (PCs) accounted for more than 93% of the total variation. The
first principal components accounted for 42.5% of the total variation mainly
due to seed length, seed width, seed weight/plant and number of seeds/plant
which had maximum and positive weight on this component. Oil content had
negative weight on PC1. Thus, PC1 related to the accessions with thick seeds,
moderate to high seed yielder with low oil content.
Genetic diversity in maize dent landraces assessed by morphological and molecular markers
Authors: Ristic Danijela , Babic Vojka , Andjelkovic Violeta , Vancetovic Jelena , Mladenovic-Drinic Snezana , Ignjatovic-Micic Dragana
Published: February 2014

Maize Research Institute ?Zemun Polje? genebank maintains a collection of
landraces grouped into 18 agro-ecological collected from ex-Yugoslavia
territories. The application and comparison of different marker systems are
important for the characterization and use of maize landraces in breeding
program, as potential sources of desirable traits. In this study, 15
morphological traits, 7 RAPD primers and 10 SSR primer pairs were applied to
i) to determine genetic distance between 21 maize dent landraces and ii)
compare results obtained on morphological and molecular markers. Phenotypic
analysis showed high level of heterogeneity between landraces. Higher level
of genetic diversity was obtained with SSR than with RAPD. Genetic distance
mean value for RAPD data was 0.35 i.e. for SSR 0.48. Based on the
morphological traits and molecular markers, unweighted pairgroup method
(UPGMA) analysis was applied for cluster analysis, using statistical NTSYSpc
program package. Cluster analysis of morphological and molecular markers
distances did not show the same population grouping. Better agreement with
agro-ecological data was obtained with RAPD markers. Correlations between
dissimilarity matrices for different types of markers were low. Data obtained
in this work could be useful for further study of a larger number of
landraces, and conservation of genetic resources and their genetic diversity.
Toxicology and cytogenetic analysis of a Drosophila melanogaster mutant resistant to Imidacloprid and DDT
Authors: Kalajdzic Predrag , Oehler Stefan , Markaki Maria , Savakis Charalambos
Published: February 2014

Resistance to all major insecticide classes has developed in numerous and
diverse insect field populations. Imidacloprid, the worldwide most used
neonicotinoid, has been extensively applied during the last decade for the
control of different insect pests. Lately, cases of sporadic resistance also
to neonicotinoids, including Imidacloprid, have been reported. Drosophila
melanogaster is one of the most popular model organisms in biology and,
although not a pest species, a promising model system for insecticide
resistance research. In this study, we present a toxicological and karyotypic
analysis of a Drosophila mutant (MiT[w-]3R2) resistant to Imidacloprid and
cross-resistant to DDT. Karyotype analysis of polytene chromosome of
MiT[w-]3R2 flies did not identify any apparent structural change of the
polytene chromosome linked with the resistance phenotype.
Genetic characterization of pathogenic fluorescent pseudomonads isolated from necrotic cherry and plum buds in Serbia
Authors: Gavrilovic Veljko , Ivanovic Zarko , Popovic Tatjana , Zivkovic Svetlana , Stankovic Slavisa , Beric Tanja , Fira Djordje
Published: February 2014

During past few years a symptoms of plum and cherry bud necrosis were
observed in some regions with significant cherry production in Serbia. Gram
negative, fluorescent, oxidative bacterial strains were isolated from the
margin of necrotic tissue. All investigated strains are levan and HR
positive, while negative results are recorded in oxidase, pectinase and
arginin dihydrolase tests (LOPAT+---+). Symptoms similar to those observed in
natural infection were obtained after artificial inoculation of cherry leaf
scares and dormant one year old cherry shoots. Investigated strains as well
as reference strain of P. syringae pv. morsprunorum cause the superficial
necrosis on artificially inoculated immature cherry fruits, but negative
results were recorded in immature pear and lemon fruit tests as well as
syringae leaves and bean pods. Gelatin and aesculin tests were negative and
tyrosinase and tartrate were positive. Investigated strains isolated from
necrotic cherry buds had identical REP-PCR pattern with reference strain of
P. syringae pv. morsprunorum. On the basis of obtained results, it was
concluded that this bacterium is causal agent of cherry trees bud necrosis in
Serbia.
Psychometric characteristics of the scale for assessment of the risk of children and juveniles for conflict with the law
Authors: Marcetic-Radunovic Gordana , Hrncic Jasna , Zegarac Nevenka
Published: February 2014

Growing needs of our experts for operative and relevant tool for risk
assessment of children and adolescents in conflict with the law initiated
construction of the Scale for Assessment of the Risk of Children and
Juveniles for Conflict with the Law (Risk Scale). This paper presents results
of research aiming on assessment of psychometric characteristics of the Scale
and its applicability by experts in centres for social work (CSW). Scale has
72 items organized in nine subscales. Research included 65 subjects from 11
to 20 years of age, assessed by the Scale by 32 experts from nine
municipality?s CSW in Serbia. Scale as a whole and its five subscales have
good reliability. Two second order factors were extracted: Risks to the
child/young person and Environmental risks that have acceptable reliability
and good criteria validity in relation to Scale of Antisocial Behaviour
Chronicity. Experts assessed that Scale is useful in practice and most of
them didn?t have any difficulties in its application. Qualitative analysis of
the result provided guidelines for further improvement of the Risk scale and
for more comprehensive education of experts it the area.
Nikola Milosevic as critic of Marxism
Authors: Stankovic Dejan
Published: February 2014

In this essay, author analyses Nikola Milosevic's critique of Marxism. His
methodological approach is the mixture of philosophy, literature and positive
sciences, mostly psychology and history. His argument against Marxism
consists of two parts: practical, mostly, ethical and political, and
theoretical, mostly, methodological and epistemic. Ethical argument against
Marxism is based on the idea of critical reconsideration of the relation
between goals and means. For Milosevic, Marxism and real socialism are
obvious examples of maxim: ?Goal justifies any means necessary for its
achievement?. Such ethical standpoint justifies the regime of terror and
manipulation. On the other hand, at the methodological and epistemic level,
Marxism is an overt example of false theory in positivistic sense. It lacks
logical consistency and empirical evidence. Being a theory without a
scientific grounds, Marxism is a mere projection of the psychological and
political attitudes of its author. Marxism is not a theory in traditional
philosophical sense, it is just a theoretical rationalization of basic
psychological and political attitudes of it creator and his successors.
Study on tip leakage vortex in an axial flow pump based on modified shear stress transport k-ω turbulence model
Authors: Zhang Desheng , Pan Dazhi , Shi Weidong , Wu Suqing , Shao Peipei
Published: February 2014

The tip leakage vortex structure and trajectory in an axial flow pump were
investigated numerically and experimentally based on the modified shear
stress transport k-? turbulence model. Numerical results were compared with
the experimental leakage vortex trajectories, and a good agreement was
presented. The detailed trajectories of tip leakage vortex show that the
starting point of tip leakage vortex occurs near the leading edge at small
flow rate, and it moves from leading edge to about 30% chord length at design
flow rate. At larger flow rate condition, the starting point of tip leakage
vortex shifts to the middle of chord.
On the semi-inverse method and variational principle
Authors: Li Xue-Wei , Li Ya , He Ji-Huan
Published: February 2014

In this Open Forum, Liu et al. proved the equivalence between He-Lee 2009
variational principle and that by Tao and Chen (Tao, Z. L., Chen, G. H.,
Thermal Science, 17(2013), pp. 951-952) for one dimensional heat conduction.
We confirm the correction of Liu et al.?s proof, and give a short remark on
the history of the semi-inverse method for establishment of a generalized
variational principle.
A Quality Assurance Program for Human Immunodeficiency Virus Seropositivity Screening of Dried-Blood Spot Specimens
Authors: Hannon W. Harry , Lewis D. Sue , Jones Wanda K. , Powell Mary K.
Published: February 2014

Epidemiologic projects have been implemented for using dried-blood spot (DBS) specimens routinely collected on filter paper from neonates as a seroepidemiologic resource to monitor seroprevalence of human immunodeficiency virus (HIV) among child-bearing women. To ensure the quality of the data base produced from the national and other epidemiologic surveys, a quality assurance program was developed to interact with all the neonatal screening laboratories. The focus of the Centers for Disease Control's quality assurance program for HIV seropositivity testing of neonatal blood specimens is to maintain a national program to produce, certify, and provide external quality control materials as DBSs on filter paper, to monitor the filter paper matrix, to operate an external performance surveillance program, and to provide other special and consultative services. The dried-blood control and surveillance materials are certified by rigorous testing for accuracy, stability, and homogeneity. Preliminary results from the first performance evaluation of screening laboratories indicated excellent performance.
Epidemic of Serratia marcescens Bacteremia and Meningitis in a Neonatal Unit in Mexico City
Authors: Zaidi Mussaret , Sifuentes José , Bobadilla Miriam , Moncada David , de León Samuel Ponce
Published: February 2014

A case-control study was conducted on an epidemic of bacteremia and meningitis caused by Serratia marcescens in the neonatal intensive care unit and special care nursery of a general hospital in Mexico City, Mexico. A 19.9% incidence of bacteremia and meningitis was recorded in contrast to 1.4% and 3.7% during pre-epidemic and postepidemic periods; a 69% mortality rate was observed. Peripheral IV catheters and the use of mixed IV fluids prepared in the wards were the major risk factors (P < 0.001). Rectal and nasopharyngeal cultures were positive in 68% of asymptomatic neonates and hand cultures were positive in 16.7% of personnel. Strains were resistant to all aminoglycosides and broad-spectrum penicillins, and belonged to the A5/8 bio-group. Containment of this outbreak was difficult because of failure to identify colonized infants early in the epidemic and because of persistent carriage of S marcescens by personnel. Comparisons between this hospital and tertiary care centers in Mexico suggest that in developing countries nosocomial infections could be of greater magnitude in secondary than in tertiary level centers.
Impact of a Recapping Device on Venepuncture-Related Needlestick Injury
Authors: Goldwater Paul N. , Law R. , Nixon A.D. , Officer J.A. , Cleland J.F.
Published: February 2014

In a 33-month prospective analysis of needlestick injuries, venepuncturists working under Centers for Disease Control (CDC) guidelines for handling used needles were shown to incur a needlestick injury for every 3,175 to 4,006 needle-handling procedures. On the other hand, users of a simple device designed to reduce the risk of injury when recapping used needles were shown to incur a needlestick only once in every 16,100 venepunctures performed (P<0.00l). This represents a fourfold reduction in the rate of needlestick injuries. We thus question the effectiveness of the CDC nonrecapping policy.
Urinary Tract Infection Following Instrumentation for Urodynamic Testing
Authors: Hamill Richard J. , Wright Charles E. , Andres Nita , Koza Maureen A.
Published: February 2014

After identifying a temporal cluster of urinary tract infections in patients who had undergone urodynamic procedures, we examined the techniques within the urodynamic laboratory and retrospectively reviewed charts of all 155 patients tested in the previous six months. The rate of acquired urinary tract infections was 18.7%. Risk factors for infection included undergoing cystometrograms and being subject to the first procedure performed in a day. Technical errors in the performance of the urodynamic studies included failure to completely disassemble the apparatus upon completion of a procedure, failure to use sterile components, and lapses in aseptic technique. Bacteria implicated in the outbreak were isolated from tubing, transducers, and flush solutions. After the institution of appropriate technique, all patients tested in the subsequent six months were followed. The rate of acquired urinary tract infection dropped to 5%. Urodynamic apparatus should be completely disassembled following the completion of a procedure; reassembly using sterile components should occur immediately prior to the next procedure; aseptic technique should be maintained; and patients should undergo routine urine screening before a procedure. Surveillance of urodynamic procedures may reveal correctable flaws in technique.
Utilization Review and Management: A Brief Analysis of a Growth Industry
Authors: Credè William B. , Hierholzer Walter J.
Published: February 2014

Inpatient hospital care consumes more than 30% of health insurance dollars regardless of the reimbursement mechanism, be it standarti fee-for-service, preferred provider organization (PPO), or health maintenance organization (HMO). It is understandable that reducing these costs has become the highest priority of health care purchasers, and that utilization review and management, the process of evaluating and attempting to reduce the cost of medical practice, has become a major growth industry with providers and purchasers of health care.
Survey of veterinarians' perceptions of borreliosis in North Carolina
Authors: Pultorak Elizabeth L. , Breitschwerdt Edward B.
Published: February 2014

Objective—To evaluate the practices and perceptions of veterinarians in North Carolina regarding borreliosis in dogs in various geographic regions of the state.

Design—Cross-sectional survey.

Sample—Data from 208 completed surveys.

Procedures—Surveys were distributed to veterinary clinics throughout North Carolina. Descriptive statistics were used to summarize perceptions pertaining to borreliosis among dogs in North Carolina.

Results—A significantly higher proportion of responding veterinarians believed that borreliosisis was endemic in the coastal (67.2%) and Piedmont (60.9%) areas of North Carolina, compared with more western regions (37.5%). The 3 variables found to be significantly different between the northern and southern regions of the state were the estimated number of borreliosis cases diagnosed by each responding veterinary clinic during the past year, the perception of borreliosis endemicity, and the perceptions related to the likelihood of a dog acquiring borreliosis in the state.

Conclusions and Clinical Relevance—Veterinarians’ perception of the risk of borreliosis in North Carolina was consistent with recent scientific reports pertaining to geographic expansion of borreliosis in the state. As knowledge of the epidemiological features of borreliosis in North Carolina continues to evolve, veterinarians should promote routine screening of dogs for Borrelia burgdorferi exposure as a simple, inexpensive form of surveillance that can be used to better educate their clients on the threat of transmission of borreliosis in this transitional geographic region.
What is the Position of Agritourism on the Walloon Tourist Market?
Authors: Dubois Charline , Schmitz Serge
Published: February 2014

With its marginal practices and diversified services, agritourism is a complex subject of study. In some European rural areas it is seen as a smart diversification solution. Even though agritourism is rather weak on the Walloon tourist market level, it is important for farmers for whom it is often a means of supplementary income. Based on crossed data concerning potential tourists, local tenants, privileged witnesses and promotional information, the position of agritourism on the Walloon tourist market is analysed. It is shown that agritourism is a multiple micro-niche market primarily complementary to other sources of tourist supply. This paper underscores how the assets of demand, of the region and of the farm all shape agritourist diversification. Instead of providing a standardized well-known product, agritourism in Wallonia is richly diverse, which creates difficulties in branding this tourist market sector.
Glufosinate Application Timing and Rate Affect Peanut Yield
Authors: Prostko Eric P. , Webster Theodore M. , Marshall Michael W. , Leon Ramon G. , Grey Timothy L. , Ferrell Jason A. , Dotray Peter A. , Jordan David L. , Grichar W. James , Brecke Barry J.
Published: February 2014

Field studies were conducted at 13 locations across the US peanut belt during 2010–2012 to evaluate peanut response to postemergence applications of glufosinate. Glufosinate was applied at 0, 41, 82, 164, 328 and 656 g ai/ha 30, 60, and 90 days after planting (DAP). There was a significant interaction for peanut yield between application time and glufosinate rate; peanut yield data were regressed on rate of glufosinate and fit to a log-logistic dose response curve by application timing. At 30 DAP, peanut yield ranged from 16 to 92% of the non-treated control, with glufosinate at 266 g/ha causing an estimated 50% reduction in yield (Y50). At 60 DAP, peanut yield ranged from 16 to 82% of the nontreated control, with Y50  =  266 g/ha of glufosinate. Peanut yield when glufosinate was applied at 90 DAP ranged from 20 to 78% of the non-treated control; Y50  =  187 g/ha of glufosinate, which was lower than that at 30 DAP and indicated greater peanut sensitivity. Peanut plants treated at 30 DAP had more time to recover from glufosinate injury at the lower rates and/or were in a less susceptible stage of growth relative to 90 DAP. These data provide peanut growers across the US with an estimate of potential yield losses associated with mis-application, off-target movement, or sprayer contamination of glufosinate.
Is in vivo manual palpation for thoracic pedicle screw instrumentation reliable?
Authors: Donohue Miriam L. , Moquin Ross R. , Singla Amit , Calancie Blair
Published: February 2014

Object

Previous reports on the accuracy of manual palpation for thoracic pedicle screw placement have been restricted to cadaveric studies. Authors of the present novel study assessed the accuracy of manual palpation for the detection of medial and lateral pedicle breaches during thoracic spine surgery in living adult humans.

Methods

Pedicle tracks were created freehand and manually palpated using a ball-tipped probe. Postoperative CT scans of all implanted thoracic and L-1 screws were evaluated with respect to screw position and the pedicle wall.

Results

Five hundred twenty-five pedicle track/screw placements were compared. There were 21 pedicles with medial breaches measuring ≥ 2 mm. The surgeon correctly identified only 4 of these pedicle tracks as having a medial breach. The surgeon correctly identified 17 of 128 pedicles with a significant (≥ 2 mm) lateral breach. One hundred two screw placements had no measurable breach in any direction (medial, lateral, or foraminal). The surgeon correctly identified 98% of these ideally placed screws.

Conclusions

In this real-time study of thoracic pedicle screw placement, the accuracy of manual palpation for detecting medial or lateral breaches that were ≥ 2 mm was disturbingly low. These findings are consistent with those in recent cadaveric evaluations of palpation accuracy and point to the critical need for more reliable alternative methods to assess pedicle integrity during the placement of thoracic pedicle screws for spine instrumentation surgery.
Acute spinal cord injury in rats should target activated autophagy
Authors: Hou Hongping , Zhang Lihai , Zhang Licheng , Tang Peifu
Published: February 2014

Object

Autophagy is a cellular mechanism of maintaining balance between protein synthesis and degradation; the latter can be induced by starvation and neurodegenerative disease. Spinal cord injury (SCI) induces necrosis and apoptosis. Autophagic flux has not yet been defined, especially the potential role of autophagy in relation to apoptosis in different tissue cells. The object of this study was to investigate the occurrence of autophagic flux and the potential role of autophagy and apoptosis post-SCI in rats.

Methods

Following creation of SCI in rats, activation of autophagic flux was detected at the protein (LC3, beclin1, and p62) and mRNA (beclin1) levels and on electron microscopy images. Distribution of LC3, colocalization of activated caspase-3, and changes in expression levels of bcl-2 and Bax were assessed to investigate the potential role of autophagy and apoptosis.

Sprague-Dawley rats were used, and T9–10 hemitransection was performed. Expression levels of LC3, beclin1, p62, bcl-2, and Bax were assessed by Western blot analysis, and beclin1 mRNA levels were assessed by reverse transcription–polymerase chain reaction. Distribution of LC3 and colocalization of activated caspase-3 were analyzed by immunohistochemistry. Autophagosome formation was investigated by electron microscopy.

Results

The authors found a dramatic elevation in LC3 and beclin1 levels near the scar region. Using double staining, they observed that upregulation of LC3 started at 4 hours in neurons and at 3 days in astrocytes after SCI. Confocal images indicated that the percentage of neurons with apoptosis was reduced, while the percentage of astrocytes with apoptosis was high at 4 hours, 8 hours, and 1 day post-SCI but decreased sharply at 3 days. Electron microscopy images provided evidence of autophagosome formation. Elimination of p62 indicated occurrence of autophagic flux. Expression levels of bcl-2 and Bax were increased and decreased, respectively, near the injury site.

Conclusions

The results of this research demonstrated that autophagic flux is activated after SCI. Potentially, inhibition of apoptosis could be a target to promote neural recovery.
A Review on Oral Lichen Planus
Authors: Islam ME , Jahan D
Published: February 2014

DOI: http://dx.doi.org/10.3329/bjdre.v4i1.18012 Bangladesh Journal of Dental Research & Education Vol.4(1) 2014: 21-25
Computer Literacy and Attitudes Towards e-learning among Bangladeshi Medical Students.
Authors: Chowdhury Nasrin Sultana , Chowdhury Nurun Nahar , Rabbi Ferdous , Tabassum Rehnuma , Ishrat Sonia
Published: February 2014

Background: The use of computer has enhanced undergraduate medical education. Computer assisted learning improves performence at examination, develops problem solving skill. The study evaluates computer literacy among the medical students in Dhaka, Bangladesh. Material and Method: Cross sectional descriptive type of study. Data collected by interviwing 322 randomly selected medical student from East West Medical College & Hospital , Dhaka, Bangladesh. Result: Maximum respondents are within 20 -22 yrs (52.8%) female (54.7%), and have average computer skill (61.8%), mostly use for personal purpose (69.6%). Among the user most of them(66.8%) have own computer at home, mostly have laptop (52.2%) from their school period (51.6%).Among most of them consider using this hamper their study (59%), but they found it helpful to improve study (38.2%).They use internet every alternative day, majority for (35.7%) email & browsing. Conclusion: This study showed that students browses net and email for recreation & social communication mostly rather than acquiring knowledge of medical science. Computer is a good source of knowledge of medical science. It can be used to gain update information of medical education. DOI: http://dx.doi.org/10.3329/updcj.v3i1.17977 Update Dent. Coll. j: 2013; 3 (1): 03-06
Lateral compression splint, a guide for stabilization of mandibular arch in case of dentoalveolar fracture of children
Authors: Quader Sheikh Md Shahriar , Shamsuzzaman Mohammad , Gofur Abdul , Fatema Shakila , Rahman Mohammad Aminur
Published: February 2014

Children (below 13 yrs of age) are usually susceptible to cranio facial trauma because of their greater cranial mass to body ratio. When compared to adults, the pattern of fractures and frequency of associated injuries are similar but the overall incidence is much lower. Treatment is usually performed without delay and can be limited to observation or closed reduction in non-displaced or minimally displaced fractures. Operative management should involve minimal manipulation and may be modified by the stage of skeletal and dental development. Open reduction and rigid internal fixation is indicated for severely displaced fractures. When tooth buds within the mandible do not allow internal fixation with plates and screws, this can be achieved with a mandibular compression splint fixed to the teeth, to the mandible with circum-mandibular wire. Children require long-term follow-up to monitor potential growth abnormalities. A case of a 9-year-old boy with fractured body of mandible managed by closed reduction using occlusal acrylic splint and circum mandibular wiring is presented. DOI: http://dx.doi.org/10.3329/updcj.v3i2.18001 Update Dent. Coll. j: 2013; 3 (2): 55-60
Individual-Based Allometric Equations Accurately Measure Carbon Storage and Sequestration in Shrublands
Authors: Mason Norman , Beets Peter , Payton Ian , Burrows Larry , Holdaway Robert , Carswell Fiona
Published: February 2014

Many studies have quantified uncertainty in forest carbon (C) storage estimation, but there is little work examining the degree of uncertainty in shrubland C storage estimates. We used field data to simulate uncertainty in carbon storage estimates from three error sources: (1) allometric biomass equations; (2) measurement errors of shrubs harvested for the allometry; and (3) measurement errors of shrubs in survey plots. We also assessed uncertainty for all possible combinations of these error sources. Allometric uncertainty had the greatest independent effect on C storage estimates for individual plots. The largest error arose when all three error sources were included in simulations (where the 95% confidence interval spanned a range equivalent to 40% of mean C storage). Mean C sequestration (1.73 Mg C ha–1 year–1) exceeded the margin of error produced by the simulated sources of uncertainty. This demonstrates that, even when the major sources of uncertainty were accounted for, we were able to detect relatively modest gains in shrubland C storage.
Insight into Conformational Change for 14-3-3σ Protein by Molecular Dynamics Simulation
Authors: Hu Guodong , Li Haiyan , Liu Jing-Yuan , Wang Jihua
Published: February 2014

14-3-3σ is a member of a highly conserved family of 14-3-3 proteins that has a double-edged sword role in human cancers. Former reports have indicated that the 14-3-3 protein may be in an open or closed state. In this work, we found that the apo-14-3-3σ is in an open state compared with the phosphopeptide bound 14-3-3σ complex which is in a more closed state based on our 80 ns molecular dynamics (MD) simulations. The interaction between the two monomers of 14-3-3σ in the open state is the same as that in the closed state. In both open and closed states, helices A to D, which are involved in dimerization, are stable. However, large differences are found in helices E and F. The hydrophobic contacts and hydrogen bonds between helices E and G in apo-14-3-3σ are different from those in the bound 14-3-3σ complex. The restrained and the mutated (Arg56 or Arg129 to alanine) MD simulations indicate that the conformation of four residues (Lys49, Arg56, Arg129 and Tyr130) may play an important role to keep the 14-3-3σ protein in an open or closed state. These results would be useful to evaluate the 14-3-3σ protein structure-function relationship.