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971.
The gobioid fish Apocryptes bato (Hamilton, 1822) is a species of mudskipper found in Bangladesh, India, and Myanmar. The reproductive biology of A. bato including sex ratio, size at sexual maturity, breeding season, fecundity, and condition factor was studied in the Payra River, southern Bangladesh during May 2016 to April 2017. A total of 1,028 specimens (303 males and 725 females) were collected. The overall sex ratio was significantly different from the expected value of 1:1 (male: female = 1:2.39, χ2 = 173.23, p < 0.05). Size at sexual maturity was estimated as 4.9 cm standard length. Monthly variations in gonadosomatic index indicate that the main breeding season is from May to December. There was a significant positive correlation of body length and body weight with fecundity. Fulton's condition factor varied in both sexes and was attributed to variations in GSI with maturity. Breeding season was significantly associated with rainfall, but not air temperature. Our findings should improve management and conservation of this fish in the Payra River and surrounding ecosystems.  相似文献   
972.
A high cholesterol diet is related to ovarian dysfunction and infertility which has been increased among young ages consuming processed food products. The present study was conducted to evaluate the role of a high cholesterol diet on the ovaries of young female rats via assessments of histopathology, immunohistochemistry, oxidative stress and apoptic markers. Also, mating of hypercholesterolemic female rats was carried out to measure the fertility and numbers of their offspring. At the same time, phytotherapy was carried out through supplementing the diet with barley and/ or date palm fruits (10%) during the experiment to assess the phyto-therapeutic impacts in attenuation of drastic hypercholesterolemic effects.Hypercholesterolemic diet-fed rats exhibited damage of the ovarian follicles and increased follicular atresia. Furthermore, expression of cleaved caspase-3 was upregulated, while PCNA was downregulated in granulosa, theca and stroma cells. Hypercholesterolemic female rats showed marked depletion of antioxidative enzymes, increased lipid peroxidation and apoptotic markers. Alterations to the female serum hormones were detected. Offspring maternally fed on hypercholesterolemic diet showed a significant decrease of body weight and altered sex ratio. However, concomitant supplementation of barley and or date fruits to hypercholesterolemic groups revealed marked improvement of ovarian structure and function.On the basis of these evidences, it is believed that the enhanced synergistic effects of barley and/or date palm fruits in the amelioration of ovarian structure and functions were elicited by the potential antioxidant activity of their phytomicronutrients, polyphenols, β-glucan and trace elements. These materials scavenge free radicals from inflamed cells that can be used to establish an effective and novel therapeutic strategy for activating ovarian cell regeneration.  相似文献   
973.
974.
Lichens are complex symbiotic organisms able to produce a vast array of compounds. The Algerian lichen diversity has only prompted little interest even given the 1085 species listed. Herein, the chemodiversity of four Algerian lichens including Cladonia rangiformis, Ramalina farinaceae, Rfastigiata, and Roccella phycopsis was investigated. A dereplication strategy, using ultra high performance liquid chromatography‐high resolution‐electrospray ionization‐mass spectrometry (UHPLC‐HRMS/MS), was carried out for a comprehensive characterization of their substances including phenolics, depsides, depsidones, depsones, dibenzofurans, and aliphatic acids. Some known compounds were identified for the first time in some species. Additionally, the lichenic extracts were evaluated for their antifungal and antimicrobial activities on human pathogenic strains (Candida albicans, Cglabrata, Aspergillus fumigatus, Staphylococcus aureus, and Escherichia coli). Cyclohexane extracts were found particularly active against human pathogenic fungi with MIC80 values ranging from 8 to 62.5 μg/mL, without cytotoxicity. This study highlights the therapeutic and prophylactic potential of lichenic extracts as antibacterial and antifungal agents.  相似文献   
975.
Metallic phase molybdenum disulfide (MoS2) is well known for orders of magnitude higher conductivity than 2H semiconducting phase MoS2. Herein, for the first time, the authors design and fabricate a novel porous nanotube assembled with vertically aligned metallic MoS2 nanosheets by using the scalable solvothermal method. This metallic nanotube has the following advantages: (i) intrinsic high electrical conductivity that promotes the rate performance of battery and eliminates the using of conductive additive; (ii) hierarchical, hollow, porous, and aligned structure that assists the electrolyte transportation and diffusion; (iii) tubular structure that avoids restacking of 2D nanosheets, and therefore maintains the electrochemistry cycling stability; and (iv) a shortened ion diffusion path, that improves the rate performance. This 1D metallic MoS2 nanotube is demonstrated to be a promising anode material for lithium‐ion batteries. The unique structure delivers an excellent reversible capacity of 1100 mA h g?1 under a current density of 5 A g?1 after 350 cycles, and an outstanding rate performance of 589 mA h g?1 at a current density of 20 A g?1. Furthermore, attributed to the material's metallic properties, the electrode comprising 100% pure material without any additive provides an ideal system for the fundamental electrochemical study of metallic MoS2. This study first reveals the characteristic anodic peak at 1.5 V in cyclic voltammetry of metallic MoS2. This research sheds light on the fabrication of metallic 1D, 2D, or even 3D structures with 2D nanosheets as building blocks for various applications.  相似文献   
976.
An encapsulation system comprising of a UV‐curable epoxy, a solution processed polymer interlayer, and a glass cover‐slip, is used to increase the stability of methylammonium lead triiodide (CH3NH3PbI3) perovskite planar inverted architecture photovoltaic (PV) devices. It is found this encapsulation system acts as an efficient barrier to extrinsic degradation processes (ingress of moisture and oxygen), and that the polymer acts as a barrier that protects the PV device from the epoxy before it is fully cured. This results in devices that maintain 80% of their initial power conversion efficiency after 1000 h of AM1.5 irradiation. Such devices are used as a benchmark and are compared with devices having initially enhanced efficiency as a result of a solvent annealing process. It is found that such solvent‐annealed devices undergo enhanced burn‐in and have a reduced long‐term efficiency, a result demonstrating that initially enhanced device efficiency does not necessarily result in long‐term stability.  相似文献   
977.

Background

Pneumonia is the fourth leading cause of death worldwide, and Streptococcus pneumoniae is the most commonly associated pathogen. Increasing evidence suggests that mesenchymal stromal cells (MSCs) have anti-inflammatory roles during innate immune responses such as sepsis. However, little is known about the effect of MSCs on pneumococcal pneumonia.

Methods

Bone marrow–derived macrophages (BMDMs) were stimulated with various ligands in the presence or absence of MSC-conditioned medium. For in vivo studies, mice intranasally-inoculated with S. pneumoniae were intravenously treated with MSCs or vehicle, and various parameters were assessed.

Results

After stimulation with toll-like receptor (TLR) 2, TLR9 or TLR4 ligands, or live S. pneumoniae, TNF-α and interleukin (IL)–6 levels were significantly decreased, whereas IL-10 was significantly increased in BMDMs cultured in MSC-conditioned medium. In mice, MSC treatment decreased the number of neutrophils in bronchoalveolar lavage fluid (BALF) after pneumococcal infection, and this was associated with a decrease in myeloperoxidase activity in the lungs. Levels of proinflammatory cytokines, including TNF-α, IL-6, GM-CSF and IFN-γ, were significantly lower in MSC-treated mice, and the bacterial load in the lung after pneumococcal infection was significantly reduced. In addition, histopathologic analysis confirmed a decrease in the number of cells recruited to the lungs; however, lung edema, protein leakage into the BALF and levels of the antibacterial protein lipocalin 2 in the BALF were comparable between the groups.

Conclusions

These results indicate that MSCs could represent a potential therapeutic application for the treatment of pneumonia caused by S. pneumoniae.  相似文献   
978.
Coffee is one of the historical socioeconomic crops. It has received an increasing attention at the global level, due to its positive interlinkage with the economic growth and on the gross domestic product for most of the producing countries, particularly, developing and least developed countries. Saudi Arabia is one of the coffee producing countries that has a relative comparative advantage of coffee cultivation. Yet, coffee cultivation has not received as much attention in Saudi Arabia as that of producing countries around the world. This study aims to assess the current state of coffee cultivation in Saudi Arabia and to investigate the potential to optimize coffee cultivation in Saudi Arabia that maximizes the net national economic return and export earnings, given limitation of cultivated areas, local market activities, and international trade activities. The study statistically analyzed primary data collected from around (65) coffee farms and traders in the study regions at the south and southwest Saudi Arabia, and optimized coffee cultivation in Saudi Arabia using LINGO optimization software. Empirical results of the study revealed the great potential of Saudi Arabia to expand coffee cultivation at south and southwest regions to meet the escalating local demand and to increase its share at the world market up to 2%. Optimization of coffee cultivation in Saudi Arabia showed a high potential to meet the local demand for coffee by producing 80.07 thousand tons grown over 2861.78 hectares and to generate a net return equivalent to $395.72 million a year, which is equivalent to $138.28 thousand per hectare and $4.94 thousand per ton of coffee. Optimizing coffee cultivation will play a substantial role to increase market share of Saudi Arabia to about 1–2% of the world market by increasing its export volume, respectively, to about 69.66 and 112.56 thousand tons, the national net economic return by about $395.86 and $395.95 million a year, and the export earnings of coffee by about $219.43–354.57 million a year, which in turns, will serve the national strategic trend to diversify the economic base and lower the dependency of incomes generated from oil exportation.  相似文献   
979.
Group B streptococcal infection (Streptococcus agalactiae) is one of the leading causes of life-threatening disease in the early neonatal period, resulting in sepsis, pneumonia, and meningitis. During invasive infections, an excessive release of pro-inflammatory cytokine, such as interleukin-6 (IL-6), thus IL-6 gene is significant, as a diagnostic marker of systemic infection of the newborns. The present study aimed to describe the epidemiology diagnostic of GBS disease in neonatal by phenotypic and genotypic methods. Nine hundred and ninety-six samples were taken at Maternity and Children Hospital, Jeddah, Saudi Arabia for a period of one year (2011–2012). Results indicated that out of 217 infected samples, twenty (9.23.0%) were positive for group B Streptococci bacteria. This study also shows that female infants are more susceptible than males. The level of IL-6 was higher in mothers above 30 years. Twenty positive Streptococci group B isolates showed bands with the cylE gene primers in the border between 228 bp, 267 bp and 50 bp. Molecular detection by Real time polymerase chain reaction was also done to detect the target (Sip gene) encoding the Sip surface immunogenic protein. Specific primers and TaqMan probe were chosen for this purpose. A Real-time PCR method targeting the sip gene of GBS in neonates after delivery has been evaluated.  相似文献   
980.
Two plant essential oils; camphor and castor were tested for insecticidal and antifeedant activity against the 4th instar larvae of Spodoptera littoralis, a serious pest on cotton in Egypt. Also the impact of LC10 of both oils on some physiological parameters in larvae was studied by using leaf dipping technique. Analysis of both oils using GC–MS revealed several insecticidal and antifeedant compounds. Our results showed higher insecticidal activity and antifeedant index of camphor oil against S. littoralis. The LC50 and the antifeedant indices were 163.1, 246.8?mg/ml and 12.69, 6.62% for camphor and castor bean oil, respectively. The total hemocyte count (THC) and differential hemocyte count (DHC) were reduced significantly after 48?h of treatment compared to controls. Both oils reduced all types of hemocytes except plasmatocytes which were reduced only by castor oil. Camphor oil decreased total proteins and carbohydrates while castor oil targeted only carbohydrate content. Both oils didn't affect the amount of total lipids. Lipase, α-amylase and glucose-6-phosphate dehydrogenase (G6PD) enzyme activities were increased significantly in larvae treated with camphor oil than other treatments. These results clearly indicate that castor and camphor oils can affect the nutritional status in S. littoralis larvae, thereby changing the internal metabolic processes in the larvae which make them as potential control agents in IPM programs against S. littoralis.  相似文献   
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