bluuebunny/crossref_metadata_2025_split huggingface dataset:
Student nurses’ perceptions of their educational environment at a school of nursing in Western Cape province, South Africa: A cross-sectional study
Authors: Mthimunye Katlego D.T. , Daniels Felicity M. 
Published: April 2019

Background: Educational environments have been found to bear a substantial relationship with the academic performance and success, as well as the retention, of students.Objectives: The study objectives were to (1) evaluate the educational environment as perceived by undergraduate nursing students at a school of nursing (SON) in Western Cape province and (2) investigate whether the educational environment, or components thereof, is perceived negatively or positively among undergraduate nursing students of different year level, gender, home language and ethnicity.Method: A quantitative research method with a cross-sectional design was implemented. Data were collected from 232 undergraduate nursing students from a SON at a university in Western Cape province, South Africa. The subscales and the items of the educational environment questionnaire were compared among undergraduate nursing students. Data were analysed by means of the IBM Statistical Package for Social Sciences (IBM SPSS-24) using analysis of variances (ANOVAs), independent-sample t-tests, mean scores, standard deviations and percentages.Results: The mean score attained for the entire participant group was 195 (standard deviation [SD] = 24.2) out of 268 (equivalent to 72.8% of maximum score), which indicated that the educational environment was perceived substantially more positively than negatively. The overall mean score was significantly higher (p < 0.05) for male students (M = 202; SD = 21) and for black students (M = 202; SD = 21). The digital resources (DR) subscale was the only subscale with a statement or item that was rated as absolute negative (M = 1.9; SD = 0.9).Conclusion: The educational environment at the institution concerned was perceived as predominantly positive by its undergraduate nursing students. Although the educational environment was predominantly perceived as positive, the results of this study also indicated that enhancements are required to improve the physical classroom conditions, skills laboratories, DR and the implemented teaching and learning strategies. It is vital for university management to prioritise the creation of an educational environment which would ensure that quality learning takes place.
HIV viraemia during pregnancy in women receiving preconception antiretroviral therapy in KwaDukuza, KwaZulu-Natal
Authors: Ntlantsana Vuyokazi , Hift Richard J. , Mphatswe Wendy P. 
Published: April 2019

Background: Preconception antiretroviral therapy (PCART) followed by sustained viral suppression is effective in preventing mother-to-child transmission of HIV. The rates of persistent and transient viraemia in such patients have not been prospectively assessed in South Africa.Objectives: We determined the prevalence of transient and persistent viraemia in HIV-positive women entering antenatal care on PCART and studied variables associated with viraemia.Methods: We performed a prospective cross-sectional observational study of HIV-positive pregnant women presenting to a primary healthcare facility in KwaZulu-Natal. All had received at least 6 months of first-line PCART. Viral load (VL) was measured, patients were interviewed, adherence estimated using a visual analogue scale and adherence counselling provided. Viral load was repeated after 4 weeks where baseline VL exceeded 50 copies/mL.Results: We enrolled 82 participants. Of them, 59 (72%) pregnancies were unplanned. Fifteen participants (18.3%) were viraemic at presentation with VL > 50 copies/mL. Of these, seven (8.5%) had viral suppression (VL < 50 copies/mL), and eight remained viraemic at the second visit. Adherence correlated significantly with viraemia at baseline. Level of knowledge correlated with adherence but not with lack of viral suppression at baseline. Socio-economic indicators did not correlate with viraemia. No instances of vertical transmission were observed at birth.Conclusions: Approximately 20% of women receiving PCART may demonstrate viraemia. Half of these may be transient. Poor adherence is associated with viraemia, and efforts to encourage and monitor adherence are essential. The rate of unplanned pregnancies is high, and antiretroviral therapy programmes should focus on family planning needs of women in the reproductive age group to prevent viral non-suppression prior to pregnancy.Keywords: Preconception Antiretroviral Therapy; HIV; Viraemia; Antenatal Care; Adherence.
Samenwerking in de landbouw en de mededingingsregels
Authors: Litjens Maria , van Rijn Thomas 
Published: April 2019

Samenwerking in de landbouw en de mededingingsregels
De Nederlandse regering wil de wetgeving aanpassen om samenwerking in de landbouw te stimuleren. De meest recente Europese PO-regels (2018) zouden de basis moeten zijn, maar deze regels zijn niet duidelijk en niet afgestemd op de uitspraak van het Hof van Justitie in de Franse witlofzaak (2017). In dit artikel werken we uit hoe de Europese benadering uitgelegd kan worden. Het Hof van Justitie spreekt over uitsluiting waardoor bij een PO het kartelverbod niet van toepassing is, terwijl de Europese wetgever alleen een afwijking aangeeft. Dit verschil in benadering en ook de complexe regelgeving maakt het invullen van de regels op nationaal niveau lastig maar niet ondoenlijk. De Nederlandse overheid moet aansturen op verheldering van de Europese PO-regels en kan tegelijkertijd naar het voorbeeld van de Duitse regelgeving haar nationale regels verbeteren.
Meta-Heuristics Approach to Knapsack Problem in Memory Management
Authors: Oppong Emmanuel Ofori , Oppong Stephen Opoku , Asamoah Dominic , Abiew Nuku Atta Kordzo 
Published: April 2019

The Knapsack Problems are among the simplest integer programs which are NP-hard. Problems in this class are typically concerned with selecting from a set of given items, each with a specified weight and value, a subset of items whose weight sum does not exceed a prescribed capacity and whose value is maximum. The classical 0-1 Knapsack Problem arises when there is one knapsack and one item of each type. This paper considers the application of classical 0-1 knapsack problem with a single constraint to computer memory management. The goal is to achieve higher efficiency with memory management in computer systems.
This study focuses on using simulated annealing and genetic algorithm for the solution of knapsack problems in optimizing computer memory. It is shown that Simulated Annealing performs better than the Genetic Algorithm for large number of processes.
Biophysical Effect of EMR with 5GHz on Male Reproductive System of Mus musclus Mice
Authors: Al-dulamey Q. Kh. , Ismail A. H. , Al-Jawwady Yasir A. 
Published: April 2019

Aim: To study the effect of microwave radiation with power density 100,150 and 200 microwatt / cm2 (μW/cm2) of exposure on male reproductive system of Mus musclus Swiss albino mice.
Study Design: Twenty mice were used in the experiment, they were divided randomly and assigned into 4 groups of 5 animals each. White mice were used in this study Mus musculus Blub/c which range between 2-3 months of age and 23 -30 gm of weight . Healthy mice were obtained from the college of veterinary in Mosul University.
Place and Duration of Study: Mosul University, College of science, Biophysics department, IRAQ, between January 2014 and April 2014.
Methodology: Mice were exposed to 100,150 and 200 μW/cm2 for 60 days. Then mice were divided into 4 groups each of group contain 5 animals. Group I: considered as control group were placed in cages without exposure. Group Π: Mice group were exposed with microwave 100 μW/cm2 for 60 days. Group Ш : Mice of this group received 150/cm2 for 60 days. Group IV : Mice of this group received 200 μW/cm2 for 60 days. After exposure testis were obtain from each male group and experiment carried out on the sperm.
Results: The results in control group without exposure the parameters as No of sperm cells in epididymis, Percentage of living sperm cells, Percentage of dead sperm cells, Percentage of normal sperm cells and Percentage of abnormal sperm cells respectively recorded with, 28.96 a ± 0.99, 87.81 a±0.82, 12.19 d±0.81, 86.66 a±0.83 and 13.44 d±0.73 respectively. The first group exposed to 100 µW/cm2 and the results of the same parameters with 15.60 b±0.49, 46.05 b±0.44, 53.96 c±0.43, 44.97 b±0.55 and 55.03 c±0.55 recpectively showed a significant decrease (p˂0.05) in No. of sperm cells in epididymis, Percentage of living sperm cells and Percentage of normal sperm cells respectively while appeared a significant increase(p˂0.05) in Percentage of dead sperm cells and Percentage of abnormal sperm cells. The second and third groups exposed to microwave radiation at 150 and 200 µW/cm2. Also the results of same parameters recorded with 11.86 c±0.23, 35.90 c±0.69, 64.23 b±0.52, 34.93 c±0.72, 65.28 b±0.46, 6.88 d±0.26, 24.72 d±0.21, 75.28 a±0.21, 23.68 d±0.45 and 76.33 a±0.45 respectively.
Conclusion: The 5GHz of microwave radiation has harmful effect of physiological and histopathological for reproductive system and avoid the exposure for long time about radiation from communication That have this same frequency as Wi –Fi or any communication from internet.
Impact of Forest Combustion on Soil Contamination by PAHs Using QuEChERS and GC-MS/MSTQD
Authors: Marzoq Hadi. Al Fahd, , Mohamed S. Al-Sewailem, , Mohamed Hamza EL-Saeid, 
Published: April 2019

The present study was conducted in one of the most dense forest area of Asir region located in the southwest of Saudi Arabia to study the Impact of Forest Combustion on surface and subsurface soil contamination by Poly Aromatic Hydrocarbons (PAHs). The major toxic effects of PAHs including cancers, immunity suppression, loss of fertility, mutagenic and cardiovascular diseases. The extraction and analytical methods, have been developed and validated for quantification of trace levels of 17 PAHs namely, Naphthalene, Acenaphthylene, Acenaphthene, Fluorene, Phenanthrene, Anthracene, Fluoranthene, Pyrene, Retene, Benzo [b+j] fluoranthene, Benzo (a)pyrene, Benzo [k] fluoranthene, 3-methylchol-anthrene, Dibenz [a,h] acridine, Indeno [1,2,3-cd]pyrene, Dibenz [a,h] anthracene and Benzo [ghi] perylene. Surface and subsurface soil samples were collected from Alsaqa and Murir post-fire forests in Asir Province, Saudi Arabia, and extracted by Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) and analyzed by Gas Chromatography-Mass Spectrometry Triple Quadrupole (GC-MS/MSTQD). The experimental results of 17 compounds of PAHs were highly satisfactory linearity, recovery and precision, especially with the tested soil samples. Recovery % ranged from 96.48±2.19 to 105.61±3.21%., the limit of detection (LOD) ranged from 3.71 to 6.77 µg kg-1. Meanwhile the limit of quantification (LOQ) for the analyzed PAHs were in the range of 10.47 to 16.42 µgkg-1. This method featured good sensitivity, lower quantification limits and the precision of the analyzed 17 PAHs. The calibration curves were linear over wide concentration ranges with correlation coefficients (r2) 0.7478 to 0.9822 for 17 PAHs analyzed by GC-MS/MSTQD. The concentrations of the investigated PAHs in Alsaqa forest surface (S) and subsurface (SS) soils ranged from F24.81±4.29 to 57.28±3.56 and 24.10±2.31to 55.47±4.15 mg kg-1dry weight respectively. Meanwhile, the PAHs concertation in Murir surface and subsurface soils ranged from 12.48±2.37 to 28.83±3.35 and 12.83±1.37 to 25.59±4.31 mg kg-1 dry weight respectively. Retene compound was detected in Alsaqa, and Murir forest investigated surface, and subsurface soil sample ranged from 57.28, 55.47, and 28.83, 25.59 mg/kg-1(ppm) respectively. Meanwhile, Retene was not detected (ND) in the control surface and subsurface soil sample. The detected PAHs by applying the modified QuEChERS and GC-MS/MSTQD method were applied successfully for the extraction and determination of the 17 PAHs in burned forest soil samples.
Abilities of Tectona grandis and Celtis zenkeri (Hardwood) Sawdust as Substrates of Pleurotus Species and Their Indigenous Fungi
Authors: Olatunji I. S. , Sobowale A. A. , Adenipekun C. O. 
Published: April 2019

Mushroom cultivation has continued to receive growing attention because of its nutritional and medicinal values. However, this study examined the effect of hardwood sawdust on the growth of Pleurotus ostreatus and Pleurotus pulmonarius were investigated. Relationship between fungal incidence of the substrates (sawdust) and that of the mushroom were examined. Both Pleurotus ostreatus and Pleurotus pulmonarius were inoculated on fermented and unfermented sawdust of Tectonal grandis and Celtis zenkeri. The fruiting bodies of the mushrooms were harvested and the growth parameters and biological efficiency was recorded. The isolated resident fungi were identified after obtaining pure cultures. The collected data were subjected to analysis (ANOVA) using Generalized Linear Model Procedure (GLM) of Statistical Analysis software (SAS). Means were separated using Duncan’s Multiple Range Test (DMRT) at p ≤ 0.05.
Some of the growth parameters of P. ostreatus were significantly (p ≤ 0.05) better than that of P. pulmonarius. Tectona grandis and Celtis zenkeri sawdust had significant (p ≤ 0.05) impact on different growth parameters of the two mushrooms. Fermentation or non-fermentation of the substrates (sawdust) had no significant (p ≤ 0.05) impact on growth parameters of the mushrooms. Growth parameters of the two mushrooms were significantly better in 0% additive (p ≤ 0.05) than in the other additive concentrations. Five fungi were identified as indigenous fungi of the unfermented sawdust which did not significantly differ from those of the fermented sawdust and mushrooms. Nutritional composition of the mushrooms that grew on fermented and unfermented sawdust were good and comparable. The mushrooms were rich in protein, fibre, ash, moisture, fat and carbohydrate. Cultivation of mushrooms on hardwood sawdust is thus an effective means of managing such waste.
A Review of Anti – Diarrheal Activity of Aegle marmelos
Authors: Rakulini R. , Kalaichelvi S. 
Published: April 2019

The aim of this study was review the anti – diarrheal activity of Aegle marmelos. Siddha literatures were obtained from the library of Unit of Siddha Medicine, University of Jaffna. Data was collected from books and internet and tabulated for the analysis. Beal Fruit Tree (Aegle marmelos) (Tamil name Vilvam, Kuvilam, Sinhala name Belli), belongs to the family of Rutaceae. It is the most valuable medicinal plant in Siddha system of Medicine due to its various medicinal properties. It is a small or medium sized deciduous tree. It has alternate leave arrangement, Its flowers are greenish white, Fruit globose, grey or yellowish colour, Seeds Numerous. Found all over the Sri Lanka. Fruit (both unripe & ripe), root – bark, leaves, rind of the ripe fruit & flowers are used in drug preparations. Un-ripe fruit is astringent, digestive & stomachic & a little constipative. According to Siddha, Aegle marmelos has bitter, astringent taste, hot potency, pungent bio availability and reduce Vatha, Pitha and Kapha dosha. Diarrhoeal diseases are amongst the most common infectious diseases worldwide resulting in 3.2% of all deaths killing about 1.8 million people globally each year. It is quite evident from this review that Aegle marmelos is an important medicinal herb and extensively used in Ayurveda, Siddha, unani and traditional medicine. Historically, Aegle marmelos has been used for the number of ethonobotanical purposes. The collected information suggests that Aegle marmelos has anti-diarrheal activity.
Combinatorial Mutation Analysis of ω‐Transaminase to Create an Engineered Variant Capable of Asymmetric Amination of Isobutyrophenone
Authors: Kim Hong‐Gon , Han Sang‐Woo , Shin Jong‐Shik 
Published: April 2019

Abstractω‐Transaminase (ω‐TA) is an important enzyme for asymmetric synthesis of chiral amines. Rapid creation of a desirable ω‐TA variant, readily available for scalable process operation, is demanded and has attracted intense research efforts. In this study, we aimed to develop a quantitative mutational analysis (i. e., R‐analysis) that enables prediction of combinatorial mutation outcomes and thereby provides reliable guidance of enzyme engineering through combination of already characterized mutations. To this end, we determined three mutatable active‐site residues of ω‐TA from Ochrobactrum anthropi (i. e., leucine 57, tryptophan 58 and valine 154) by examining activities of nine alanine‐scanning mutants for seven substrate pairs. The R‐analysis of the mutatable residues is based on assessment of changes in relative activities for a series of structurally analogous substrates. Using three sets of substrates (five α‐keto acids, six arylalkylamines and three arylalkyl ketones), we found that combination of two point mutations display additive effects of each mutational outcome such as steric relaxation for bulky substrates or catalytic enhancement for amination of ketones. Consistent with the R‐analysis‐based prediction, the ω‐TA variant harboring triple alanine mutations, i. e. L57A, W58A and V154A, showed high activity improvements for bulky substrates, e. g. a 3.2×104‐fold activity increase for 1‐phenylbutylamine. The triple mutant even enabled asymmetric amination of isobutyrophenone, carrying a branched‐chain alkyl substituent to be accepted in a small binding pocket that normally shows a steric limit up to an ethyl group, with >99% ee of a resulting (S)‐amine.magnified image
Highly Efficient and Stable Solar Cells with Hybrid of Nanostructures and Bulk Heterojunction Organic Semiconductors
Authors: Ram Kiran Sreedhar , Singh Jai 
Published: April 2019

AbstractThe power conversion efficiency (PCE) of a hybrid bulk hetero‐junction organic solar cell with an active layer of a blend of PBDT TS1 (donor) and PCBM (acceptor) incorporated with copper zinc tin sulfide (CZTS) quantum dots (QDs) and zinc oxide (ZnO) nanowires is simulated. It is found that the incorporation of CZTS‐QDs of a single radius (1.5 nm) enhances the PCE from 9.1% to 12.34% and of 13 different radii CZTS‐QDs elevates PCE to 14.96%. This enhancement occurs mainly due to the enhancement in absorption that enhances short‐circuit current density (Jsc) and fill factor (FF). Finally, a layer of ZnO nanowires is added on top of the glass to reduce the reflection losses and absorption of ultraviolet light in the active layer that causes degradation and reduces the stability of organic solar cells (OSCs). The hybrid structure, thus simulated, has an enhanced PCE of 16.32% and is expected to be relatively more stable. It is expected that the results of this simulation may inspire all researchers interested in the fabrication of highly efficient hybrid OSCs.
Suboptimal response rates to hypomethylating agent therapy in chronic myelomonocytic leukemia; a single institutional study of 121 patients
Authors: Coston Tucker , Pophali Prateek , Vallapureddy Rangit , Lasho Terra L. , Finke Christy M. , Ketterling Rhett P. , Carr Ryan , Binder Moritz , Mangaonkar Abhishek A. , Gangat Naseema , Al‐Kali Aref , Litzow Mark , Zblewski Darci , Pardanani Animesh , Tefferi Ayalew , Patnaik Mrinal M. 
Published: April 2019

AbstractHypomethylating agents (HMA) are currently the only FDA approved therapy for patients with chronic myelomonocytic leukemia (CMML). In the current retrospective study, we assessed response rates as adjudicated by the IWG (International Working Group) MDS (myelodysplastic syndrome) and MDS/MPN myeloproliferative neoplasm overlap syndrome response criteria, in 121 CMML patients treated with Azacitidine (AZA, n = 56) and Decitabine (DAC, n = 65). The overall response rates were 41% by the IWG MDS (AZA‐ 45%, DAC‐39%), and 56% by the IWG MDS/MPN (AZA‐56%, DAC‐58%) response criteria, with CR (complete remission) rates of <20% for both agents, by both criteria. There were no significant differences in response rates between proliferative and dysplastic CMML. Moreover, 29% of CMML patients in a CR with HMA progressed to AML (blast transformation), underscoring the limited impact of these agents on disease biology. Progression after HMA response was associated with a median overall‐survival (OS) of 8 months, while median OS in patients with primary HMA failure was 4 months. Lower serum LDH levels (<250 Units/L) were associated with HMA responses by both criteria; while ASXL1 and TET2 mutational status had no impact. HMA treated patients had a longer median OS (31 vs 18 months; P = .01), in comparison to those treated with conventional care regimens (excluding observation only patients), without any differences between AZA vs DAC (P = .37). In conclusion, this study highlights the inadequacies of HMA therapy in CMML, retrospectively validates the IWG MDS/MPN response criteria and underscores the need for newer, rationally derived therapies.
Step‐Growth Copolymerization Between an Immobilized Monomer and a Mobile Monomer in Metal–Organic Frameworks
Authors: Anan Shizuka , Mochizuki Yumi , Kokado Kenta , Sada Kazuki 
Published: April 2019

AbstractThe A–A/B–B step‐growth copolymerization between a monomer immobilized in the crystalline state and a monomer mobile in the solution state is demonstrated. One of the two monomers was immobilized as organic ligands of the metal–organic framework (MOF) and polymerized with the mobile guest monomer, resulting in the formation of linear polymers. The polymerization behavior was completely different from that of the solution polymerizations. In particular, the degrees of polymerization (DP) converged to a specific value depending on the MOF structures. The inevitable termination is caused not by imperfectness of the polymerization reaction, but by the selection of the two polymerization partners among the several adjacent immobilized monomers. This is fully supported by the Monte Carlo simulation on the basis of the polymerization mechanism. Precise immobilization of monomers in the supramolecular assemblies is a promising way for the controlled A–A/B–B step‐growth polymerization.
Molecular‐Dynamics‐Simulation‐Directed Rational Design of Nanoreceptors with Targeted Affinity
Authors: Sun Xiaohuan , Riccardi Laura , De Biasi Federico , Rastrelli Federico , De Vivo Marco , Mancin Fabrizio 
Published: April 2019

AbstractHere, we demonstrate the possibility of rationally designing nanoparticle receptors with targeted affinity and selectivity for specific small molecules. We used atomistic molecular‐dynamics (MD) simulations to gradually mutate and optimize the chemical structure of the molecules forming the coating monolayer of gold nanoparticles (1.7 nm gold‐core size). The MD‐directed design resulted in nanoreceptors with a 10‐fold improvement in affinity for the target analyte (salicylate) and a 100‐fold decrease of the detection limit by NMR‐chemosensing from the millimolar to the micromolar range. We could define the exact binding mode, which features prolonged contacts and deep penetration of the guest into the monolayer, as well as a distinct shape of the effective binding pockets characterized by exposed interacting points.