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While plastic mulch (PM) can increase crop yield and reduce weed growth, there are negative environmental impacts associated with the production, use, and disposal of PM films. There is currently a gap in the literature on the negative impacts of PM throughout its entire lifecycles, with most studies limited to investigating the global warming potential (GWP) of the practice during field operations. The objective of this study is to conduct a comprehensive life cycle assessment (LCA) for low density polyethylene PM for maize to investigate the environmental impacts of all stages of mulching. The LCA was conducted using SimaPro with data obtained from relevant literature and from the Ecoinvent database. The system boundaries include the production, transportation, installation, operation, removal, and disposal of the PM. The results reveal that the field operation of the PM has the highest impact in GWP. A sensitivity analysis was conducted to assess the effect of parameter variability for the field operations stage, and the GWP impact was observed to be sensitive to changes in carbon dioxide and net ecosystem carbon budget. The production of PM has the highest impact in abiotic depletion, but this impact can be reduced through energy recovery. Incineration yields the least harmful impacts, but the results of the study may vary depending on the exact disposal method. More data on the disposal of PM is needed to assess its impacts reliably and reduce uncertainties in the results. The impact of PM can be mitigated through proper waste management and mitigation measures, including regulations on disposal.

The diagnostic performance of the available risk assessment models for VTE in patients who are critically ill receiving pharmacologic thromboprophylaxis is unclear.

Purpose To examine barriers and adherence to topical glaucoma medication in a pediatric glaucoma population in Saudi Arabia.Methods This cross-sectional study was undertaken at the King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia during 2016–2017. Parents (father or mother) of children aged 6 months to 15 years with a history of glaucoma were interviewed. Rasch analysis was performed to assess the psychometric properties of the developed 12-item barriers-to-adherence tool (BAT-12) and to identify barriers deemed highly important. The 12-items were adapted from previous studies examining different barriers to adherence in different populations. Medication adherence was assessed by asking parents a series of closed-ended questions about the frequency of missed medications. Determinants of missed medications on at least 1 out of the last 3 days were examined using Poisson regression.Results One hundred and six parents were interviewed. The 12-item scale had acceptable psychometric properties. Barriers deemed important were forgetfulness (logit −0.59), complex dosing regimen (logit 0.09), and being too busy with other work/activities (logit 0.14). When asked how often, on average, their child missed the prescribed medication, 26 (24.5%) reported daily, 17(16.0%) reported few times per week, and 32 (30.2%) reported once per week. A third of parents (n = 37, 34.9%) reported having missed giving all drops on at least one day in the last 3 days. Poisson regression with robust variance revealed that increase in age of the child (prevalence ratio, 1.08 [95% CI, 1.03–1.14]; p = 0.003) and increase in parents’ barriers score (prevalence ratio, 2.13 [95% CI, 1.49, 3.03]; p < 0.001) were significantly associated with having missed medications on at least one out of the last three days while adjusting for the effect of father's current employment status and area of residence.Conclusions The tool we used to examine barriers to glaucoma medication had acceptable psychometric properties and could be used and strengthened in future studies. Our study highlights poor adherence to glaucoma medications among children with glaucoma.

This research aims to characterize reservoir properties by applying rock physics and AVO analysis followed by pre-stack inversion. Two approaches are investigated: One approach addresses the case in which there are wells and seismic data, and the other addresses cases where only seismic data are available. The former approach is achieved by using well-log cross-plots for rock physics modeling to determine the feasibility and pay zone through gas fluid substitution followed by AVO analysis. Pre-stack inversion is then used to predict porosity and gas saturation. In the second approach, a synthetic seismogram is generated and compared to the observed seismic trace at the location of interest by forward modeling P-wave interval velocity and density. The best-matching P-wave velocity and density are subsequently used to generate synthetic well logs at the same location. Pre-stack inversion is then performed on these synthetic wells to predict porosity and gas saturation. Property prediction is performed by a feasibility study and pay zone calculation using rock physics modeling of the nearest well to the seismic block. Finally, the results of this case are validated using real wells. This new approach of reservoir characterization using synthetic wells is applied on reservoir channels and yielded a fairly good porosity prediction but a less accurate prediction of gas saturation.

Novel Zn(II)–benzohydrazide complexes have been synthesized using Zn(NO3)2·6H2O salt. All new synthesises were investigated by available analytical and spectral tools to demonstrate their formulae. Binuclear complexes were proposed with all ligands through pentadentate mode of bonding. Octahedral geometry was the only structural form proposed for complexes. Benzohydrazide derivatives coordinate by the same mode, which point to negligible effect of p-substituents on donor site environment. This mode was verified basically by IR and 1H, 13C NMR spectra. According to XRD patterns, crystallite particles of complexes were appeared in nanosized range. Such feature is preferable in variable application fields. Molecular modeling and molecular docking were interested in this study to strengthen experimental studies. One of these complexes [Zn(II)–H2L2] was examined to be an additive optimizing the performance of traditional fertilizer (NH4NO3) in planting corn hybrid. This complex significantly improved components of photosynthetic carbon assimilation as photosynthetic pigments, sucrose, and soluble sugars. Interestingly, the applied complex induced responses, which were consistently higher than those treated by traditional fertilizer (NH4NO3). Therefore, these results highlight the promising behavior of Zn(II)–H2L2complex in planting improvement.

Several approaches have been proposed to address the challenge of catheter ablation of persistent atrial fibrillation (AF). However, the optimal ablation strategy is unknown. We sought to evaluate the efficacy of pulmonary vein isolation (PVI) plus low-voltage area (LVA) ablation using contemporary high-density mapping to identify LVA in patients with persistent AF.

ABSTRACTOne-day old goat kids were separately allocated to three treatment groups; Baladi (n = 56), Shami (n = 47) and Hybrid (n = 25). The LBW and BWG (kg/kid) of the kids were recorded at weekly intervals, and the survivability was calculated at the end of the trial. The results indicated that mean weekly Live body weight (LBW) shows a significant increase (P < 0.05) for both males and females of the three goat breeds tested. The final LBW (12-week-age) of both sexes of Shami goats was significantly (P < 0.05) higher than Baladi and Hybrid. Male goats (15.45 ± 3.65, 17.71 ± 5.23 and 15.96 ± 4.99 kg/kid) had significantly (P < 0.05) higher LBW than their female counterparts (12.52 ± 3.41, 14.92 ± 5.10 and 11.01 ± 2.64 kg/kid) in Baladi, Shami and Hybrid, respectively. Total BWG of Shami goat males and females was higher than Baladi and Hybrid breeds. The total survivability was higher in Baladi (94.64%) than in Shami (91.49%) and Hybrid (80.00%). In conclusion, the present findings indicated that production performances of goats were considerably affecting by their breed and sex, and Shami breed had supported comparatively better growth responses. Therefore, Shami goat breed might be recommended for more economic and profitable for rearing under good farming management in Jordan.

Chemical flooding has been widely used in the oil industry since the 1980s for enhanced oil recovery (EOR) process. Previous studies have shown that the effectiveness of calcium carbonate scale inhibitors is affected by many factors, such as water composition, system pressure, temperature, production rates, pH etc. The breakthrough of the EOR chemicals in the production well could also affect scale formation process and interfere with the scale treatment program as well. However, the studies on the impacts of injected EOR chemicals to scale inhibitor performances are very limited. This paper presents the comprehensive laboratory study on the impacts of the EOR chemicals on CaCO3scale formation and prevention using static bottle and dynamic tube blocking methods. The EOR chemicals used in this study are a combination of surfactants and polymers. Three different types of inhibitors were evaluated: tri-phosphonate, penta-phosphonate, and polyacrylate based chemicals. Inhibition (%) from the bottle test and minimum effective dose (MED) based on the tube blocking method were determined for each inhibitor at 160 °F. Scale precipitates from the bottle tests were also characterized for morphology and polymorphs using environmental scanning electron (ESEM) and X-ray diffraction (XRD) techniques. Results suggest that the performance of scale inhibitors could be substantially affected by the EOR chemicals. In dynamic tube blocking tests, the MED values of inhibitors were increased roughly 10 times with the EOR chemicals. The static bottle tests showed considerable changes under the test conditions. The impact of EOR chemicals were also demonstrated by the remarkable ranges of crystal morphologies, changing from simple aragonite columns to nanorod, distorted spheroid, and flower-like superstructure in the presence of EOR chemicals and inhibitors.

Context:The number of women in academic medicine has increased significantly in recent years. However, female authors are underrepresented in major medical journals.Objective:The aim was to determine the distribution of female first and senior authors of original articles in four American endocrinology journals over a period of 25 years.Design:A retrospective analysis of the literature was undertaken.Setting:Four journals were selected: Journal of Clinical Endocrinology & Metabolism; Thyroid; Journal of Bone and Mineral Researchand Diabetes Care.Participants:The first and senior authors of all original articles published in 1991, 1996, 2001, 2006 and 2015 were included.Intervention:none.Results:The main outcome measure was the distribution of female first and senior authors of original articles. A total of 4 148 articles were included. Of these, 28.9% (1 199) articles were authored by females of whom 751 (62%) were first authors. Over the study period, there was a shift towards female authorship. A statistically significant trend was observed (p < 0.001).

There is limited data on the scar burden in patients with atrial fibrillation (AF). In this study, we sought to evaluate the presence and extent of an abnormal left atrial (LA) substrate in patients with paroxysmal or persistent AF.

ABSTRACTThe study aimed to determine the effect of goat breed (Shami, Mountain Black and Hybrid) on testicular and epididymal sperm reserves. The study was conducted at Mutah University Animal Farm, Jordan in March 2016. The study area lies between Latitude of 31°27″ N, Longitude of 35°74″ W, and an altitude of 960 m. Average temperature and relative humidity recorded during the study were 14.6°C and 59.0%, respectively. Hybrid had the heaviest (P = 0.04) right tail epididymal weight (6.36 ± 0.3 g), the highest (P = 0.03) epididymosomatic index (0.60 ± 0.1 g/kg), and the widest (P = 0.02) testicular width (0.32 ± 0.03 cm/kg) relative to body weight. Epididymal sperm concentrations in the right testicular side were the highest (P = 0.04) in Hybrid (0.530 ± 0.15 × 109sperm/ml) compared to Shami (0.386 ± 0.04 × 109sperm/ml) and Mountain Black (0.322 ± 0.10 × 109sperm/ml). Total testicular-epididymal sperm concentrations in both testes were the highest (P = 0.04) in Hybrid (0.810 ± 0.20 × 10 sperm/ml) compared to Shami (0.764 ± 0.09 × 109sperm/ml) and Mountain Black (0.716 ± 0.12 × 109sperm/ml). Furthermore, Hybrid had the highest (P = 0.05) epididymal body sperm concentrations (0.252 ± 0.05 × 109sperm/ml) in both testes compared to Mountain Black and Shami. Taken together, the outcomes of this work highlighted the testicular and epididymal sperm traits in bucks of three breeds native to the semiarid region of Jordan. Hybrid displayed greater testicular traits than Shami and Mountain Black.

Small ruminants (sheep and goats) play a predominant role in the economy of million people, and have provided meat, milk, skin, wool and fiber for centuries. Animals undergo various kinds of stressors, i.e. physical, nutritional, chemical, psychological and heat stress (HS). Among all, HS is the most concerning at present in the ever-changing climatic scenario. Climate change is the most serious long-term challenge faced by small ruminants’ owners worldwide. HS results in decreased growth, reproduction, production, milk quantity and quality, as well as natural immunity, making animals more vulnerable to diseases, and even death. Thus, HS results in great economic losses, emphasizing the necessity to objectively assess animal welfare. The increasing demand for animal products paralleled by the frequent hot climate is a serious threat for the agriculture sector. The ability of sheep and goats to cope with HS without harming their welfare and productive performance has been often overrated. To date, little attention has been paid to comprehensive detailed data on the adverse effect of HS on sheep and goats. Therefore, this review discusses in detail the sheep and goats’ behavioral, physiological, molecular/cellular, hematological, biochemical and immunological responses under HS conditions. In addition, this review also presents the adverse effects of HS on reproduction and fertility, milk quantity and quality, feed intake, and water consumption of sheep and goats. Finally, this review suggests various methods for HS alleviation. In conclusion, HS impairs productivity and well-being in sheep and goats. The improved understanding of the impact of HS on small ruminants will help in developing management techniques to alleviate HS and highlighting the need for future researches on HS in sheep and goats.

The article presents modeling and interpretation of production and actual pressure-transient responses of open-hole and horizontal multistage fracturing (MSF) wells in Saudi Arabia. It mentions that knowing whether to drill toward the minimum horizontal stress or maximum horizontal stress affects fracture behavior and ultimate production in heterogenous and tight carbonate reservoirs. A chart depicting Well B Pressure-Derivative response is cited.

The article studies the effect of zinc ions on calcium carbonate scale formation and scale inhibition performance under oilfield conditions. Calcium carbonate scale may cause operational inefficiency, equipment malfunction and system shutdown. Chemical changes due to the presence of zinc ions alter the effectivity of scale inhibitors with the active ingredients amino tri(methylene phosphonic acid) (ATMP), diethylenetriamine penta(methylene phosphonic acid) (DETPMP), or acrylate polymers.

Clinical characteristics, mode of presentation and pathological features of resectable carcinoma of the colon have been studied in 224 cases presenting between January 1971 and December 1975. Minimum length of follow-up is five years and is complete. Forty-three per cent of patients survived five years or more, only 23 per cent of tumours being early in histological terms. The conventional high risk groups contributed little to the total and their active surveillance will not significantly improve the overall statistics.

Several letters to the editor are presented in response to articles in previous issues including "When B-schoolers act as company consultant" in the July 28, 1975 issue, "A plan to slow the flood of illegal aliens" in the August 11, 1975, and "A spine stiffener" in the July 21, 1975 issue.

Probing behavior of adult potato leafhopper, Empoasca fabae (Harris), on alfalfa, Medicago sativa L., plants maintained at 3 water levels, was monitored using an AC electronic feeding monitor. Two waveform feeding types were predominant in occurrence and duration: Ia, multiple-cell laceration; and Ic, continuous ingestion without stylet movement. Number of probes per insect did not differ significantly among water treatments. Mean number of waveform events per insect, Ic waveform events per insect, waveform events per probe, Ia waveform events per probe, and Ic waveform events per probe, occurred significantly more often on high and moderate water than on low water. Probing duration per insect, Ia waveform duration per insect, and Ia waveform duration per event were not significantly different among water treatments. Duration of Ic waveforms per insect were significantly longer on low water than on high or moderate water, whereas duration of Ia tended to be longer on high and moderate water. Probing duration per probe was not significantly different among water treatments. Duration of Ia waveform per probe was significantly longer on high and moderate water than on low water, whereas duration of Ic was significantly longer on low water than on high and moderate. Probing duration per event and Ic waveform duration per event were significantly longer on low water than on high and moderate. Water deficit in alfalfa results in a shift of probing behavior in potato leafhopper from predominantly Ia to Ic waveforms, the latter being a behavior that is less injurious to the plant.