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الملخص: أهداف البحث: الاختناق في الفترة المحيطة بالولادة هو السبب الرئيسي لوفيات الأطفال دون الشهر الخامسة ويمارس ضغطا كبيرا على النظام الصحي. تعتبر المراقبة الكافية للجنين أثناء المخاض أمرا بالغ الأهمية في الكشف المبكر عن ضائقة الجنين من أجل منع الاختناق في الفترة المحيطة بالولادة. يتم استخدام عدة طرق لمراقبة الجنين بفاعلية متفاوتة. هدفت هذه الدراسة إلى التحقق من مدى فعالية مقايسة اللاكتات الشريانية السرية في التنبؤ بالنتائج الضارة في الفترة المحيطة بالولادة. طريقة البحث: كانت دراسة طولية مستقبلية شملت 160 امرأة حامل في المرحلة النشطة من المخاض عند الأوان والذين استوفوا معايير الاشتمال. تم استقطابهم باستخدام تقنية أخذ العينات المتتالية وتم إجراء تخطيط القلب لهم. ثم تم تصنيفهم إلى مجموعات تخطيط القلب الطبيعية وغير الطبيعية. عند الولادة، تم جمع الدم الشرياني السري لجميع الأطفال ومعايرته من أجل اللاكتات في الدم وتم ربط المستويات بنتيجة الفترة المحيطة بالولادة. تم قياس النتائج في الفترة المحيطة بالولادة بواسطة درجات أبغار، والقبول في وحدة حديثي الولادة واعتلال الدماغ الإقفاري بنقص التأكسج. تم إجراء التحليل لتحديد حساسية ونوعية اللاكتات الشرياني السري في التنبؤ باختناق الولادة واعتلال الدماغ الإقفاري بنقص التأكسج وقبول وحدة حديثي الولادة. النتائج: كان متوسط العمر ± الانحراف المعياري بين مجموعتي تخطيط القلب، طبيعي (30.55 ±5.59) سنة وغير طبيعي (29.86 ±5.51) سنة، متشابها. تنبأ تركيز اللاكتات الشرياني السري الحرج الذي يزيد عن 9.1 مليمول/لتر بدرجات أبغار 9.1 مليمول/لتر مع حساسية 61.90% (فترة الثقة 38,4-81,9) ونوعية 91.30% (فترة الثقة 85,3-95,4). تنبأت مستويات لاكتات الشريان السري > 11.2 مليمول/لتر بتطور اعتلال الدماغ الإقفاري بنقص التأكسج عند الولدان بحساسية 100% (فترة الثقة 39,8-100) ونوعية 88.39% (فترة الثقة 82,3-93,0). الاستنتاجات: يرتبط لاكتات الشريان السري بنتائج الحمل الضارة وهو أداة ممتازة للتنبؤ بالنتائج الضارة لحديثي الولادة. Abstract: Background: Perinatal asphyxia is a leading cause of under-5 mortality and exerts great pressure on the health system. Adequate foetal monitoring in labour is paramount in the early detection of foetal distress to prevent perinatal asphyxia. Several methods of foetal monitoring are in use with varying efficacy. This study investigated the efficacy of umbilical arterial (UA) lactate assay in predicting adverse perinatal outcomes. Methodology: This was a prospective longitudinal study involving 160 pregnant women in the active phase of labour at term who met the inclusion criteria. They were recruited using a consecutive sampling technique and underwent a cardiotocography. Then they were classified into normal and abnormal cardiotocographic groups. At delivery, the UA blood of all of the babies was collected and assayed for serum lactate, and the levels were correlated with the perinatal outcome. The perinatal outcomes were measured by Apgar scores, admission into the neonatal unit, and hypoxic ischaemic encephalopathy. Analysis was done to determine the sensitivity and specificity of UA lactate in predicting birth asphyxia, hypoxic ischaemic encephalopathy, and neonatal unit admission. Results: The mean age ± standard deviation (SD) between the two cardiotocography (CTG) groups, normal years (30.55 ± 5.59) and abnormal years (29.86 ± 5.51), were similar. A critical UA lactate concentration > 9.1 mmol/L predicted Apgar scores < 7 at 5 min with a sensitivity and specificity of 76.47% (CI: 50.1–93.2) and 91.55% (CI: 85.7–95.6%), respectively. Also, the need for neonatal unit admission was predicted at a cut-off point >9.1 mmol/L with a sensitivity of 61.90% (CI: 38.4–81.9) and specificity of 91.30% (CI: 85.3–95.4). Umbilical artery lactate levels > 11.2 mmol/L predicted the development of hypoxic ischaemic encephalopathy in neonates with a sensitivity of 100% (CI: 39.8–100.0) and specificity of 88.39% (CI: 82.3–93.0). Conclusion: Umbilical artery lactate correlates with adverse pregnancy outcomes and is an excellent tool for predicting adverse neonatal outcome.

In this work, we conduct a detailed study to understand the photoelectrochromic properties of Al-Pt co-doped tungsten oxide (WO3). Similarly, we support the photoelectrochromic findings with material characterization, providing additional understanding of the photoelectrochromic performance exhibited by the prepared samples. Additionally, we discuss the effects of Al and Pt doping on photoelectrochromic performance in detail, with a focus on X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) combined with EDS, X-ray photoelectron spectroscopy (XPS), and optical transmittance. XRD peaks confirm the presence of hexagonally-structured WO3 in the prepared samples with a polycrystalline nature, and a similar observation is confirmed via TEM analysis. Surface characterizations conducted through SEM and EDS analyses unveil the morphologies and particle sizes. Optical studies show a bandgap of 1.88 eV and 1.95 eV for Al doped and Al-Pt co-doped WO3, indicating bandgap shrinkage in comparison to the optical bandgap of WO3 of 2.36 eV. The Al-Pt co-doping results in a significant enhancement in photoelectrochromic performance, attaining an optical modulation of 43.61 % at 550 nm and consequently 85 % of the initial transmittance recovered after 2 h of bleaching in the dark. This is an improvement in comparison to the Al doped sample which attains a coloration depth of 43.15 % at 550 nm with only 75 % of the original transmittance being recovered after 2 h under dark conditions.

Rice sheath blight, caused by the soil-borne fungus Rhizoctonia solani (teleomorph: Thanatephorus cucumeris, Basidiomycota), is one of the most devastating phytopathogenic fungal diseases and causes yield loss. Here, we report on a very high prevalence (100%) of potential virus-associated double-stranded RNA (dsRNA) elements for a collection of 39 fungal strains of R. solani from the rice sheath blight samples from at least four major rice-growing areas in the Philippines and a reference isolate from the International Rice Research Institute, showing different colony phenotypes. Their dsRNA profiles suggested the presence of multiple viral infections among these Philippine R. solani populations. Using next-generation sequencing, the viral sequences of the three representative R. solani strains (Ilo-Rs-6, Tar-Rs-3, and Tar-Rs-5) from different rice-growing areas revealed the presence of at least 36 viruses or virus-like agents, with the Tar-Rs-3 strain harboring the largest number of viruses (at least 20 in total). These mycoviruses or their candidates are believed to have single-stranded RNA or dsRNA genomes and they belong to or are associated with the orders Martellivirales, Hepelivirales, Durnavirales, Cryppavirales, Ourlivirales, and Ghabrivirales based on their coding-complete RNA-dependent RNA polymerase sequences. The complete genome sequences of two novel RNA viruses belonging to the proposed family Phlegiviridae and family Mitoviridae were determined.

Abstract Stress freezing is an important and powerful procedure in 3-dimensional experimental stress analysis using photoelasticity. The application of the stress freezing technique to extract stress components from loaded engineering structures has, however, declined over the years even though its principles are well established. This is attributed to huge costs arising from energy consumption during the process. In addition, significant time is needed to generate the desired information from isoclinic and isochromatic fringes. To overcome the limitations of stress freezing in photoelasticity and transform it into an economical device for stress analysis in an engineering environment, a new stress freezing cycle that lasts 5 h is proposed. The proposed technique is used in several applications of elastomeric seals with different cross-sectional profiles to assess their suitability. It was found that reducing the cycle time can lead to huge energy savings without compromising the quality of the fringes. Moreover, the use of isochromatic only to extract stress components leads to a shorter processing time to achieve desirable information since the process of obtaining isoclinic data is involving. In this paper, results of stress analysis from stress-frozen elastomeric seals with various cross-sections using the new stress freezing cycle are presented.

Introduction: This study investigates the impact of informative prior on Bayesian structural equation model (BSEM) with heteroscedastic error structure. A major drawback of homogeneous error structure is that, in most studies the underlying assumption of equal variance across observation is often unrealistic, hence the need to consider the non-homogenous error structure. Methods: Updating appropriate informative prior, four different forms of heteroscedastic error structures were considered at sample sizes 50, 100, 200 and 500. Results: The results show that both posterior predictive probability (PPP) and log likelihood are influenced by the sample size and the prior information, hence the model with the linear form of error structure is the best. Conclusions: The study has been able to address sufficiently the problem of heteroscedasticity of known form using four different heteroscedastic conditions, the linear form outperformed other forms of heteroscedastic error structure thus can accommodate any form of data that violates the homogenous variance assumption by updating appropriate informative prior. Thus, this approach provides an alternative approach to the existing classical method which depends solely on the sample information.

The physicochemical, material and compressional properties of the Irvingia gabonensis (O’Rorke) Bail polymer were evaluated and compared with xanthan gum and hydroxy propyl methylcellulose (HPMC). The Irvingia polymer was extracted using established methods and processed using two methods of drying, that is, oven-drying and freeze-drying. The compression mechanisms were evaluated using the Heckel and Kawakita equations. The mechanical strength of the tablets was evaluated using crushing strength and friability. The results showed that the Irvingia kernel polymer was slightly acidic, free of heavy metals, with irregularly shaped particles that exhibited some degree of crystallinity. The Irvingia kernel polymer was directly compressible and formed intact non-disintegrating tablets similar to the standard polymers. The Heckel and Kawakita equations indicated that the Irvingia polymer deformed plastically with fast onset and a high amount of plastic deformation compared to xanthan gum and HPMC. The freeze-dried Irvingia gum showed significantly (p

A majority of lymphatic valves tend to form in proximity to vessel junctions, and it is often proposed that disturbed flow at junctions creates oscillating shear stress that leads to accumulation of transcription factors which bring about valvogenesis at these sites. In images of networks of dorsal skin lymphatics from embryonic mice (day E16), we compared simulated fluid flow patterns and observed distributions of the transcription factor Prox1, which is implicated in valve formation. Because of creeping-flow conditions, flow across vessel junctions was not 'disturbed', and within a given vessel, shear stress varied inversely with local conduit width. Prox1 concentration was indeed localised to vessel end-regions, but over three networks was not consistently correlated with the vessel normalised-distance distribution of either fluid shear stress or shear-stress axial gradient. These findings do not support the presently accepted mechanism for the role of flow in valve localisation.

Abstract Background Healthcare workers are a burnout-prone occupational group and the prevalence is particularly high among physicians. With the prevailing low physician-patient ratio in Nigeria which has worsened with the recent wave of physician emigration, among other socio-economic constraints; a setting for high physician burnout may have been nurtured. Our survey set out to determine the prevalence of burnout among physicians practicing in Nigeria, ascertain the factors that were associated with the development of burnout and evaluate the respondents’ perceived impact of physician burnout on patient safety. Methods We used the Oldenburg burnout inventory as the measurement tool for burnout in the cross-sectional study conducted between November and December, 2019 among physicians in five tertiary health institutions in Nigeria. A 5- point Likert-type scale was used to evaluate the participants rating of their perceived impact of physician burnout on patient safety. Data entry and analysis were done using IBM Statistical package for social sciences software version 25 and the level of statistical significance was determined by a p value

Abstract Background World Health Organization guidelines recommend preventive chemotherapy with praziquantel to control morbidity due to schistosomiasis. The primary aim of this cross-sectional study was to determine if 4 years of annual mass drug administration (MDA) in primary and secondary schools lowered potential markers of morbidity in infected children 1 year after the final MDA compared to infected children prior to initial MDA intervention. Methods Between 2012 and 2016 all students in two primary and three secondary schools within three kilometers of Lake Victoria in western Kenya received annual mass praziquantel administration. To evaluate potential changes in morbidity we measured height, weight, mid-upper arm circumference, hemoglobin levels, abdominal ultrasound, and quality of life in children in these schools. This study compared two cross-sectional samples of Schistosoma mansoni egg-positive children: one at baseline and one at year five, 1 year after the fourth annual MDA. Data were analyzed for all ages (6–18 years old) and stratified by primary (6–12 years old) and secondary (12–18 years old) school groups. Results The prevalence of multiple potential morbidity markers did not differ significantly between the egg-positive participants at baseline and those at 5 years by Mann Whitney nonparametric analysis and Fisher’s exact test for continuous and categorical data, respectively. There was a small but significantly higher score in school-related quality of life assessment by year five compared to baseline by Mann Whitney analysis (P = 0.048) in 13–18 year olds where malaria-negative. However, anemia was not positively impacted by four annual rounds of MDA, but registered a significant negative outcome. Conclusions We did not detect differences in morbidity markers measured in a population of those infected or re-infected after multiple MDA. This could have been due to their relative insensitivity or a failure of MDA to prevent morbidity among those who remain infected. High malaria transmission in this area and/or a lack of suitable methods to measure the more subtle functional morbidities caused by schistosomiasis could be a factor. Further research is needed to identify and develop well-defined, easily quantifiable S. mansoni morbidity markers for this age group.

Abstract Background Omega-3 fatty acids’ inclusion as feed supplement in the diets of both human and animals has been found to play a significant role in body metabolism. The aim of this present study was to evaluate the effects of graded doses of omega-3 fatty acids on haematology and body weight of adult male and female Rattus norvegicus (Wistar albino rats) as a model animal. Methods A total of seventy-two adult male and female albino rats were randomly assigned into two experimental units. Each unit was grouped into three and received different treatment diets. Blood erythrocytes and weight were sampled on days 0, 14 and 28 to evaluate haematological parameters and body weight. Results Results showed concentration- and time-dependent significant increases (p < 0.05) in the packed cell volume (PCV), haemoglobin (Hb), white blood cells (WBCs), mean cell volume (MCV) and mean cell haemoglobin (MCH) and non-significant change (p > 0.05) in the red blood cells (RBCs) and mean cell haemoglobin concentration (MCHC) in male rats after day 0. In female rats, significant increases (p < 0.05) were recorded in the PCV, Hb, MCV and MCH, whereas no significant increase was observed in the RBCs. Activities of WBCs and MCHC showed mixed trend in female rats. The results of the body weight recorded non-significant increases (p > 0.05) in both experimental units. Conclusion Our findings depict that the use of omega-3 fatty acids in the diets of both male and female rats produced a dose-dependent effect on blood formation while its role in controlling weight gain was observed. Hence, its intake in both animal and human diets should be rightly prescribed.

The majority of formulae for predicting in-channel mixing by longitudinal dispersion are based on empirical evidence from medium to large rivers, whereas small creeks and streams are under-represented despite their hydrological and ecological importance. In this study, twenty-six formulae for predicting the longitudinal dispersion coefficient (Kx) were evaluated for their applicability to small channels using field measurements and hydraulic modeling. Predicted values for Kx, following guidelines recommended in the original publications for the formulae, were compared to measured dispersion coefficients obtained from sodium-chloride plumes injected into two small channels (a concrete-lined, trapezoidal channel and a small, natural stream) based on fitting the Hayami solution to the one-dimensional advection-dispersion equation (ADE) to each plume. The predicted Kx coefficients from the formulae were also utilized to create model-simulated plumes, which were compared to those measured well downstream of the point of injection. The findings demonstrate that the predictive accuracy of the twenty-six formulae was extremely variable; none were able to predict the dispersion process in the small channels with better than ± 50% accuracy. These results show that “universal” formulae are plagued with a large degree of uncertainty and should be used with caution when applied to small channels, although more robust predictions are possible with some formulae if site-specific data are available for calibration.

The face is the second most important biometric part of the human body, next to the finger print. Recognition of face image with partial occlusion (half image) is an intractable exercise as occlusions affect the performance of the recognition module. To this end, occluded images are sometimes reconstructed or completed with some imputation mechanism before recognition. This study assessed the performance of the principal component analysis and singular value decomposition algorithm using discrete wavelet transform (DWT-PCA/SVD) as preprocessing mechanism on the reconstructed face image database. The reconstruction of the half face images was done leveraging on the property of bilateral symmetry of frontal faces. Numerical assessment of the performance of the adopted recognition algorithm gave average recognition rates of 95% and 75% when left and right reconstructed face images were used for recognition, respectively. It was evident from the statistical assessment that the DWT-PCA/SVD algorithm gives relatively lower average recognition distance for the left reconstructed face images. DWT-PCA/SVD is therefore recommended as a suitable algorithm for recognizing face images under partial occlusion (half face images). The algorithm performs relatively better on left reconstructed face images.

Experiments were performed to investigate bubble behaviors and pool boiling Critical Heat Flux (CHF) on a thin flat rectangular copper heater fabricated on Printed Circuit Board (PCB), at various inclination angles. The surface inclination angles were 0°, 45°, 90°, 135°, and 180°. Results showed the Onset of Nucleate Boiling (ONB) heat flux increased with increasing heater orientation from 0° to 90°, while early ONB occurred when the heater faced downwards (135° and 180°). The nucleate boiling was observed to be unstable at low heat flux (1–21% of CHF) and changed into typical boiling when the heat flux was above 21% of CHF. The result shows the CHF decreased with increasing heater orientation from 0° to 180°. In addition, the bubble departure diameter at the heater facing upwards (0°, 45°, and 90°) was more prominent compared to that of the heater facing downward (135°). The nucleation site density also observed increased with increasing heat flux. Moreover, the departed bubbles with larger size were observed to require a longer time to re-heat and activate new nucleation sites. These results proved that the ONB, CHF, and bubble dynamics were strongly dependent on the heater surface orientation. Keywords: Critical heat flux, Inclination angle, Pool boiling, Bubble behavior

This work reports on the use of low-cost pineapple leaf fiber (PALF) as an alternative reinforcing material to the established, commonly used material for prosthetic socket fabrication which is carbon-fiber-reinforced composite (CFRC) due to the high strength and stiffness of carbon fiber. However, the low range of loads exerted on a typical prosthetic socket (PS) in practice suggests that the use of CFRC may not be appropriate because of the high material stiffness which can be detrimental to socket-limb load transfer. Additionally, the high cost of carbon fiber avails opportunities to look for an alternative material as a reinforcement for composite PS development. PALF/Methyl Methacrylate-based (MMA) composites with 0°, 45° and 90° fiber orientations were made with 5–50 v/v fiber volume fractions. The PALF/MMA composites were subjected to a three-point flexural test to determine the effect of fiber volume fraction and fiber orientation on the flexural properties of the composite. The results showed that 40% v/v PALF/MMA composite with 0° fiber orientation recorded the highest flexural strength (50 MPa) and stiffness (1692 MPa). Considering the average load range exerted on PS, the flexural performance of the novel composite characterized in this work could be suitable for socket-limb load transfer for PS fabrication.

Evidence-based research had shown that elevated alkali treatment of pineapple leaf fiber (PALF) compromised the mechanical properties of the fiber. In this work, PALF was subjected to differential alkali concentrations: 1, 3, 6, and 9% wt/wt to study the influence on the mechanical and crystal properties of the fiber. The crystalline and mechanical properties of untreated and alkali-treated PALF samples were investigated by X-ray diffractometry (XRD), Fourier transform infrared spectroscopy (FTIR), and tensile testing analysis. The XRD results indicated that crystal properties of the fibers were modified with 6% wt/wt alkali-treated PALF recording the highest crystallinity and crystallite size of 76% and 24 nm, respectively. The FTIR spectra suggested that all alkali-treated PALF samples underwent lignin and hemicellulose removal to varying degrees. An increase in the crystalline properties improved the mechanical properties of the PALF treated with alkali at 6% wt/wt, which has the highest tensile strength (1620 MPa). Although the elevated alkali treatment resulted in decreased mechanical properties of PALF, crystallinity generally increased. The findings revealed that the mechanical properties of PALF not only improve with increasing crystallinity and crystallite size, but are also dependent on the intermediate bond between adjacent cellulose chains.

The aim of the work is to improve the release properties of curcumin onto human breast cancer cell lines using coated halloysite nanotubes (HNTs) with chitosan as a polycation. A loading efficiency of 70.2% (w/w) was attained for loading 4.9 mg of the drug into 0.204 g bed volume of HNTs using the vacuum suction method. Results acquired from Brunauer-Emmett-Teller (BET), Fourier-transform infrared (FTIR) spectroscopy, transmission electron microscopy (TEM), scanning electron spectroscopy (SEM), zeta potential, and thermogravimetric analysis (TGA) indicated the presence of the drug and the biopolymer in and around the nanotubes. The release properties of drug-loaded HNTs (DLHNTs) and chitosan-coated drug-loaded HNTs (DLHNTs-CH) were evaluated. The release percentages of DLHNTs and DLHNTs-CH after 6 h were 50.7 and 37%, respectively. Based on the correlation coefficients obtained by fitting the release nature of curcumin from the two samples, the Korsmeyer-Peppas model was found to be the best-fitted model. In vitro cell viability studies were carried out on the human breast cancer cell line MCF-7, using the MTT and trypan blue exclusion assays. Prior to the Trypan blue assay, the IC50 of curcumin was determined to be ~30 µM. After 24 h of incubation, the recorded cell viability values were 94, 68, 57, and 51% for HNTs, DLHNTs-CH, DLHNTs, and curcumin, respectively. In comparison to the release studies, it could be deducted that sustained lethal doses of curcumin were released from the DLHNTs-CH within the same time. It is concluded from this work that the “burst release” of naked drugs could be slowly administered using chitosan-coated HNTs as potential drug carriers.

The influence of animal wastes on crude oil degradation potential of strains of Proteus vulgaris and Bacillus subtilis isolated from animal wastes (poultry and pig droppings) and petroleum-polluted soil was compared in laboratory studies. Both bacterial strains were selected for high crude oil degradation ability after screening many isolates by the 2,6-dichlorophenol indophenol method. Analyses by gas chromatography (GC) showed that degradation of crude oil was markedly enhanced (88.3–97.3% vs 72.1–78.8%) in soil amended with animal wastes as indicated by the reduction of total petroleum hydrocarbon (TPH). TPH reduction by animal waste bacterial strains in animal waste-amended soil was more than the reduction by strains from soil contaminated with petroleum (P < 0.001). The greatest reduction of TPH (96.6–97.3% vs 80.4–95.9%) was by poultry waste strains and it occurred in soil amended with poultry waste. GC analyses of n-alkanes showed that although shorter chains were preferentially degraded [32.0–78.5% (C8–23) vs 6.3–18.5% (C24–36)] in normal soil, biodegradation of longer chains increased to 38.4–46.3% in animal waste-amended soil inoculated with the same animal wastes’ strains. The results indicate that these animal waste strains may be of potential application for bioremediation of oil-polluted soil in the presence of the wastes from where they were isolated.

In this work, optimization parameters were developed to capture plant metabolites from Dioclea Reflexa (DR) seed ex-tracts onto halloysites nanotubes (HNTs). A one-step pool of the crude extracts at neutral pH from the HNT lumen failed to elicit a reduction in breast cancer, Michigan Cancer Foundation-7 (MCF-7) cell viability. However, the pH-dependent elution of metabolites revealed that the acidic pH samples exhibited profound antiproliferative effects on the cancer cells compared to the basic pH metabolites using both trypan blue dye exclusion assay and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) viability test. pH~5.2 samples demonstrated by half-maximal inhibitory concentration (IC50) of 0.8 mg and a cyclic voltammetry oxidation peak potential and current of 234 mV and 0.45 µA, respectively. This indicates that the cancer cells death could be attributed to membrane polarization/depolarization effects of the sample. Fluorescence-activated cell sorting (FACS) studies confirmed that the plant metabolites affected breast cancer apoptotic signaling pathways of cell death. The studies proved that plant metabolites could be captured using simplified screening procedures for rapid drug discovery purposes. Such procedures, however, would require the integration of affordable analytical tools to test and isolate individual metabolites. Our approach could be an important strategy to create a library and database of bioactive plant metabolites based on pH values.

Mass drug administration (MDA) using praziquantel is the WHO-recommended approach for control of schistosomiasis. However, few studies have compared the impact of different schedules of MDA on the resultant infection levels. We wished to evaluate whether annual MDA was more effective than less frequent treatments for reducing community-level prevalence and intensity of Schistosoma mansoni infections.We performed a cluster randomized trial (ISRCTN 14849830) of 3 different MDA frequencies over a 5 year period in 75 villages with moderate (10%-24%) initial prevalence of S. mansoni in school children in western Kenya. Praziquantel was distributed by school teachers to students either annually, the first 2 years, or every other year over a 4 year period. Prevalence and intensity of infection were measured by stool examination in 9-12 year old students using the Kato-Katz method at baseline, each treatment year, and for the final evaluation at year 5. S. mansoni prevalence and intensity were also measured in first year students at baseline and year 5.Twenty-five schools were randomly assigned to each arm. S. mansoni prevalence and infection intensity in 9-12 year old students significantly decreased within each arm from baseline to year 5 but there were no differences between arms. There were no differences in infection levels in first year students either within or between arms.Strategies employing 2 or 4 rounds of MDA had a similar impact in schools with moderate initial prevalence, suggesting that schistosomiasis control can be sustained by school-based MDA, even if provided only every other year.

Dioclea reflexa bioactive compounds have been shown to contain antioxidant properties. The extracts from the same plant are used in traditional medical practices to treat various diseases with impressive outcomes. In this study, ionic mobility in Saccharomyces cerevisiae cells in the presence of D. reflexa seed extracts was monitored using electrochemical detection methods to link cell death to ionic imbalance. Cells treated with ethanol, methanol, and water extracts were studied using cyclic voltammetry and cell counting to correlate electrochemical behavior and cell viability, respectively. The results were compared with cells treated with pore-forming Amphotericin b (Amp b), as well as Fluconazole (Flu) and the antimicrobial drug Rifampicin (Rif). The D. reflexa seed water extract (SWE) revealed higher anodic peak current with 58% cell death. Seed methanol extract (SME) and seed ethanol extract (SEE) recorded 31% and 22% cell death, respectively. Among the three control drugs, Flu revealed the highest cell death of about 64%, whereas Amp b and Rif exhibited cell deaths of 35% and 16%, respectively, after 8 h of cell growth. It was observed that similar to SWE, there was an increase in the anodic peak current in the presence of different concentrations of Amp b, which also correlated with enhanced cell death. It was concluded from this observation that Amp b and SWE might follow similar mechanisms to inhibit cell growth. Thus, the individual bioactive compounds from the water extracts of D. reflexa seeds could further be purified and tested to validate their potential therapeutic application. The strategy to link electrochemical behavior to biochemical responses could be a simple, fast, and robust screening technique for new drug targets and to understand the mechanism of action of such drugs against disease models.

Airflow dynamics over beach-foredune systems can be complex. Although a great deal is known about the effects of topographic forcing and vegetation cover on wind-field modification, the role of large woody debris (LWD) as a roughness element and modifier of boundary layer flow is relatively understudied. Individual pieces of LWD are non-porous elements that impose bluff body effects and induce secondary flow circulation that varies with size, density, and arrangement. Large assemblages of LWD are common on beaches near forested watersheds and collectively have a degree of porosity that increases aerodynamic roughness in ways that are not fully understood. A field study on a mesotidal sandy beach with a scarped foredune (Calvert Island, British Columbia, Canada) shows that LWD influences flow patterns and turbulence levels. Overall mean and fluctuating energy decline as flow transitions across LWD, while mean energy is converted to turbulent energy. Such flow alterations have implications for sand transport pathways and resulting sedimentation patterns, primarily by inducing deposition within the LWD matrix.

The sol-gel and cross-linking processes have been used by researchers to synthesize silica-based nanostructures and optimize their size and morphology by changing either the material or the synthesis conditions. However, the influence of the silica nanostructures on the overall physicochemical and mechanistic properties of organic biopolymers such as chitosan has received limited attention. The present study used a one-step synthetic method to obtain chitosan composites to monitor the uptake and release of a basic cationic dye (methylene blue) at two different pH values. Firstly, the composites were synthesized and characterized by Fourier Transform Infrared Spectroscopy (FTIR) and X-ray Diffraction (XRD) to ascertain their chemical identity. Adsorption studies were conducted suing methylene blue and these studies revealed that Acetic Acid-Chitosan (AA-CHI), Tetraethylorthosilicate-Chitosan (TEOS-CHI), Acetic Acid-Tetraethylorthosilicate-Chitosan (AA-TEOS-CHI), and Acetic Acid-Chitosan-Tetraethylorthosilicate (AA-CHI-TEOS) had comparatively lower percentage adsorbances in acidic media after 40 h, with AA-CHI adsorbing most of the methylene blue dye. In contrast, these materials recorded higher percentage adsorbances of methylene blue in the basic media. The release profiles of these composites were fitted with an exponential model. The R-squared values obtained indicated that the AA-CHI at pH ~ 2.6 and AA-TEOS-CHI at pH ~ 7.2 of methylene blue had steady and consistent release profiles. The release mechanisms were analyzed using Korsmeyer-Peppas and Hixson-Crowell models. It was deduced that the release profiles of the majority of the synthesized chitosan beads were influenced by the conformational or surface area changes of the methylene blue. This was justified by the higher correlation coefficient or Pearson’s R values (R ≥ 0.5) computed from the Hixson-Crowell model. The results from this study showed that two of the novel materials comprising acetic acid-chitosan and a combination of equimolar ratios of acetic acid-TEOS-chitosan could be useful pH-sensitive probes for various biomedical applications, whereas the other materials involving the two-step synthesis could be found useful in environmental remediation of toxic materials.

Rice tungro disease is a complex disease caused by the interaction between Rice tungro bacilliform virus and Rice tungro spherical virus (RTSV). RTSV alone does not cause recognizable symptoms in most Asian rice (Oryza sativa) plants, whereas some African rice (O. glaberrima) plants were found to become stunted by RTSV. Stunting of rice plants by virus infections usually accompanies the suppression of various cell wall-related genes. The expression of cell wall-related genes was examined in O. glaberrima and O. sativa infected with RTSV to see the relationship between the severity of stunting and the suppression of cell wall-related genes by RTSV. The heights of four accessions of O. glaberrima were found to decline by 14 to 34% at 28 days post-inoculation (dpi) with RTSV, whereas the height reduction of O. sativa plants by RTSV was not significant. RTSV accumulated more in O. glaberrima plants than in O. sativa plants, but the level of RTSV accumulation was not correlated with the degree of height reduction among the four accessions of O. glaberrima. Examination for expression of genes for cellulose synthase A5 (CESA5) and A6 (CESA6), cellulose synthase-like A9 (CSLA9) and C7, and -expansin 1 (expansin 1) and 15 precursors in O. glaberrima and O. sativa plants between 7 and 28 dpi with RTSV showed that the genes such as those for CESA5, CESA6, CSLA9, and expansin 1were more significantly suppressed in stunted plants of O. glaberrima at 14 dpi with RTSV than in O. sativa, suggesting that stunting of O. glaberrima might be associated with these cell wall-related genes suppressed by RTSV. Examination for expression of these genes in O. sativa plants infected with other rice viruses in previous studies indicated that the suppression of the expansin 1 gene is likely to be a signature response commonly associated with virus-induced stunting of Oryza species. These results suggest that stunting of O. glaberrima by RTSV infection might be associated with the suppression o

The bis(pyrazole)zinc(II) benzoate complexes bis(3,5-diphenylpyrazole)zinc(II) benzoate (1), bis(3,5-diphenylpyrazole)zinc(II) 3,5-dinitrobenzoate (2), bis(3,5-diphenylpyrazole)zinc(II) 4-hydroxybenzoate (3), and bis(3,5-di-tert-butylpyrazole)zinc(II) 2-chlorobenzoate (4) were synthesized from the reaction of 3,5-diphenylpyrazole (L1) or 3,5-di-tert-butylpyrazole (L2), zinc(II) acetate and the appropriate benzene carboxylic acid. The molecular structure of complex 2 confirmed that these zinc(II) benzoate complexes adopt a 4-coordinate tetrahedral geometry. All four complexes were screened as catalysts for the copolymerization of carbon dioxide (CO2) and cyclohexene oxide (CHO) and were found to be active for the formation of poly(cyclohexene carbonate) (PCHC) at CO2 pressures as low as 1.0 MPa under solvent-free conditions and without the use of a co-catalyst. At some reaction condition, most of the catalysts produced PCHC with high carbonate content of up to 98% and a good amount of cyclic cyclohexene carbonate (CCHC). The copolymers produced have low to moderate molecular weights (5200–12300 g/mol) and with polydispersity indices that vary from 1.19 to 2.50. Matrix Assisted Laser Desorption/Ionization-Time of Flight Mass Spectra (MALDI-TOF MS) of these copolymers showed they have benzoate and hydroxyl end groups.

The title compound, (C6H16N)[Fe3(CH3CO2)8O(H2O)]·C7H8, was serendipitously crystallized from a reaction of disilanol with iron(II) acetate. The trinuclear acetatoferrate(III) anion has a triethylammonium cation as the counterion. The three Fe atoms lie on the vertices of a regular triangle and are octahedrally coordinated. The complete coordination of the anion includes shared ligands among the three metal ions: a central tribridging O atom and six bidentate bridging acetyl groups. The six-coordinations of two of the metal ions are completed by a monodentate acetate ligand, whereas that of the third metal ion is completed by a water molecule. The uncoordinated triethylammonium cation is involved in N—H...O hydrogen bonding to a singly coordinated acetyl group. The coordinated aqua molecule is involved in bifurcated O—H...O hydrogen bonding. C—H...O interactions are also observed. The toluene solvent molecule is disordered over two sets of sites in a 0.609 (11):0.391 (11) ratio.

The title compound, trans-[RhCl(C18H12Cl3P)2(CO)]·C3H6O, contains an Rh(I) atom in a distorted square-planar coordination with a P—Rh—P angle of 175.27 (2)° and Rh—P bond lengths of 2.3127 (4) and 2.3219 (4) Å. The rhodium complexes link each other through weak intermolecular contacts between the acetone methyl groups and the carbonyl O atom. Interactions between the acetone solvent molecule and the Cl—Rh unit results in a reduced P—Rh—Cl angle of 86.675 (15)°.

The use of metal compounds such as cisplatin and its derivatives as therapeutic and diagnostic agents against various diseases is well established. Although metallodrugs have been very successful clinically, low therapeutic selectivity and the potential toxicity of the metal compounds mandate the need for a continuous search for more efficient and specific treatments. Hence, the use of computer‐aided drug design (CADD), molecular modelling and theoretical studies in designing, selecting and applying potential drug candidates have become ever more necessary. Among the many computational and theoretical techniques, molecular docking and density functional theory play significant roles in predicting drug activity. Recent methodologies, within the past 5 years, that rely on these techniques to advance the adoption of potential metallodrugs are highlighted and thoroughly discussed. This is because advancements in computing power have led to the wide use of CADD approaches for drug discovery, development and analysis to shorten the time and reduce the costs associated with drug discovery. [ABSTRACT FROM AUTHOR]