A Note on Classification of Spatially Homogeneous Rotating Space-Times According to Their Teleparallel Killing Vector Fields in Teleparallel Theory of Gravitation

In this paper we classify spatially homogeneous rotating space-timesaccording to their teleparallel Killing vector fields using direct integration technique. It turns out that the dimension of the teleparallel Killing vector fields is 5 or 10. In the case of 10 teleparallel Killing vector fields the space-time becomes Minkowski and all the torsion components are zero. Teleparallel Killing vector fields in this case are exactly the same as in general relativity. In the cases of 5 teleparallel Killing vector fields we get two more conservation laws in the teleparallel theory of gravitation. Here we also discuss some well-known examples of spatially homogeneous rotating space-times according to their teleparallel Killing vector fields.     

A UPLC-DAD-Based Bio-Screening Assay for the Evaluation of the Angiotensin Converting Enzyme Inhibitory Potential of Plant Extracts and Compounds: Pyrroquinazoline Alkaloids from Adhatoda vasica as a Case Study

Angiotensin converting enzyme (ACE) plays a crucial role in regulating blood pressure in the human body. Identification of potential ACE inhibitors from medicinal plants supported the idea of repurposing these medicinal plants against hypertension. A method based on ultra-performance liquid chromatography (UPLC) coupled with a diode array detector (DAD) was used for the rapid screening of plant extracts and purified compounds to determine their ACE inhibitory activity. Hippuryl-histidiyl-leucine (HHL) was used as a substrate, which is converted into hippuric acid (HA) by the action of ACE. A calibration curve of the substrate HHL was developed with the linear regression 0.999. The limits of detection and quantification of this method were found to be 0.134 and 0.4061 mM, respectively. Different parameters of ACE inhibitory assay were optimized, including concentration, incubation time and temperature. The ACE inhibition potential of Adhatoda vasica (methanolic-aqueous extract) and its isolated pyrroquinazoline alkaloids, vasicinol (1), vasicine (2) and vasicinone (3) was evaluated. Compounds 1–3 were characterized by various spectroscopic techniques. The IC₅₀ values of vasicinol (1), vasicine (2) and vasicinone (3) were found to be 6.45, 2.60 and 13.49 mM, respectively. Molecular docking studies of compounds 1–3 were also performed. Among these compounds, vasicinol (1) binds as effectively as captopril, a standard drug of ACE inhibition.     

Thermogravimetric and differential thermal analyses of fluorescein dye in inert and static air atmosphere

Journal of Thermal Analysis and Calorimetry - Fluorescein dye was prepared and characterized on the basis of microanalytical methods, FTIR, NMR and UV–visible spectroscopy in order to ensure...     

Formulation and Evaluation of a Clove Oil-Encapsulated Nanofiber Formulation for Effective Wound-Healing

Wound-healing is complicated process that is affected by many factors, especially bacterial infiltration at the site and not only the need for the regeneration of damaged tissues but also the requirement for antibacterial, anti-inflammatory, and analgesic activity at the injured site. The objective of the present study was to develop and evaluate the natural essential oil-containing nanofiber (NF) mat with enhanced antibacterial activity, regenerative, non-cytotoxic, and wound-healing potential. Clove essential oil (CEO) encapsulated in chitosan and poly-ethylene oxide (PEO) polymers to form NFs and their morphology was analyzed using scanning electron microscopy (SEM) that confirmed the finest NFs prepared with a diameter of 154 ± 35 nm. The successful incorporation of CEO was characterized by Fourier transform infra-red spectroscopy (FTIR) and X-ray diffractometry (XRD). The 87.6 ± 13.1% encapsulation efficiency and 8.9 ± 0.98% loading of CEO was observed. A total of 79% release of CEO was observed in acidic pH 5.5 with 117% high degree of swelling. The prepared NF mat showed good antibacterial activity against Staphylococcus aureus and Escherichia coli and non-cytotoxic behavior against human fibroblast cell lines and showed good wound-healing potential.     

光谱指数的植被叶片含水量反演

利用光谱技术监测植被水分状况是了解植被生理状况及生长趋势的重要手段之一。选择艾比湖湿地自然保护区作为靶区。采用聚类分析、变量投影重要性分析(VIP)以及敏感性分析等方法，对植被不同含水量进行分级，并针对不同等级的植被含水量进行估算及验证。结果表明： (1)基于聚类分析中的欧氏距离的方法将植被叶片相对含水量划分为高等、中等、低等三个等级，其范围分别为70.76%～80.69%，53.27%～70.76%，31.00%～53.27%。在中红外与远红外(1 350～2 500 nm)之间，反射率越低植被含水量越高；波长380～1 350 nm范围，无此现象。(2)应用VIP方法可知，所选的8种植被水分指数VIP值均超过了0.8，说明植被水分指数预测能力均较强且差别不显著。其中MSI，GVMI与植被叶片相对含水量的非线性三次拟合函数效果最佳，MSI决定系数R2为0.6575和GVMI决定系数R2为0.674 2。植被叶片相对含水量在30%～45%范围，MSI指数的NE值最低，在45%～90%范围时，GVMI指数的NE值最低。NDWI₁₂₄₀指数的NE值在70%左右起伏较大，说明NDWI₁₂₄₀ 指数在植被含水量为70%左右，预测能力较差。(3)通过误差分析可知GVMI指数反演的结果误差最小，不同的植被指数对不同含水量的植被估算结果相差较为明显，因此分段估算植被含水量是有必要的。综上所述，利用高光谱遥感技术对监测艾比湖保护区植被生长及干旱环境提供基础研究。     

Design and analysis of a gallium lanthanum sulfide based nanoplasmonic coupler yielding 67% efficiency

In this paper, we propose a novel ultra-compact nanoplasmonic coupler using gallium lanthanum sulfide (GLS) which yields an efficiency of 67% at the optical communication wavelength. The analysis has been done numerically using the finite-difference time-domain method. Our proposed coupler can operate at a broad frequency range and easier to fabricate than couplers with multi-section tappers since it is a simple rectangular-shaped coupler with no variation along the whole length.     

Thermogravimetric analyses revealed the bioenergy potential of <Emphasis Type="Italic">Eulaliopsis binata</Emphasis>

The present study was focused on the thermal degradation of Eulaliopsis binata biomass produced on a salt-affected soil without any fertilizer or pesticide applications. The plant biomass was subjected to thermal degradation experiments at three heating rates, 10, 30 and 50 K min^?1. The kinetic analyses were performed through isoconversional models of Kissinger–Akahira–Sunose and Flynn–Wall–Ozawa, followed by the calculation of thermodynamic parameters of activation. The high heating value was calculated as 15.10 MJ mol^?1. The activation energy values of the grass were shown to be ranging from 118 through 240 kJ mol^?1. Energy difference of enthalpies of activation between the reagent and the activated complex was in accordance with activation energies. Pre-exponential factors indicated the reaction to follow first-order kinetics. Gibbs free energy for the grass was measured to be ranging from 171 to 174 kJ mol^?1. Our data have shown that E. binata biomass offers remarkable potential as a low-cost biomass for bioenergy.     

Seimatoric acid and colletonoic acid:Two new compounds from the endophytic fungi,Seimatosporium sp.and Colletotrichum sp.

A new metabolite,named seimatoric acid(1),representing a new oxobutanoic acid derivative has been isolated from Seimatosporium sp., in addition to four known compounds viz.,2-hydroxymethyl-4β,5α,6β-trihydroxycyclohex-2-enone(2),(-)-phyllostine(3),(+)-epiepoxydon(4) and(+)-epoxydon monoacetate(5).Similarly one new benzoic acid derivative,named colletonoic acid(6) was isolated from the ethyl acetate fraction of Colletotrichum sp.The structures of the new compounds were elucidated by detailed ~1 H NMR,~(13)C NMR,COSY,HMQC.HMBC spectroscopic analysis,and HR-E1-MS.Seimatoric acid(1)was also isolated from another taxonomical unidentified fungal strain 4295 in ourgroup.The structures of the known compounds were elucidated by their spectral data comparison to literature data.Preliminary studies showed that colletonoic acid(6) showed good antibacterial,antifungal,and antialgal activities.     

Current Status of Endoplasmic Reticulum Stress in Type II Diabetes

The endoplasmic reticulum (ER) plays a multifunctional role in lipid biosynthesis, calcium storage, protein folding, and processing. Thus, maintaining ER homeostasis is essential for cellular functions. Several pathophysiological conditions and pharmacological agents are known to disrupt ER homeostasis, thereby, causing ER stress. The cells react to ER stress by initiating an adaptive signaling process called the unfolded protein response (UPR). However, the ER initiates death signaling pathways when ER stress persists. ER stress is linked to several diseases, such as cancer, obesity, and diabetes. Thus, its regulation can provide possible therapeutic targets for these. Current evidence suggests that chronic hyperglycemia and hyperlipidemia linked to type II diabetes disrupt ER homeostasis, thereby, resulting in irreversible UPR activation and cell death. Despite progress in understanding the pathophysiology of the UPR and ER stress, to date, the mechanisms of ER stress in relation to type II diabetes remain unclear. This review provides up-to-date information regarding the UPR, ER stress mechanisms, insulin dysfunction, oxidative stress, and the therapeutic potential of targeting specific ER stress pathways.     

Aloeverasides A and B: Two Bioactive C‐Glucosyl Chromones from Aloe vera Resin

Two new C‐glucosyl chromones named aloeverasides A ( 1 ) and B ( 2 ) were isolated from the resin of Aloe vera (L.) Burm.f . The structures of the two new natural products were elucidated based on 1D‐ (¹H‐ and ¹³C‐NMR) and 2D‐NMR (COSY, HSQC, and HMBC) spectroscopic techniques and mass spectrometry (ESI‐MS). Aloeverasides A ( 1 ) and B ( 2 ) were evaluated for their anticancer activity, and both induced a 76.4 and 70.5% growth inhibition of the breast cancer cell line (MDA‐MB‐231) at a concentration of 100 μm . Both compounds were also evaluated for their 1,1‐diphenyl‐2‐picryl‐hydrazyl antioxidant, urease enzyme, and α‐glucosidase enzyme inhibition activities. Aloeverasides A ( 1 ) and B ( 2 ) displayed good urease enzyme inhibition activities (62 and 55%, resp.), as well as antioxidant activity in which aloeveraside A ( 1 ) had a value of 60% inhibition, while aloeveraside B ( 2 ) demonstrated a more potent antioxidant activity with 80% inhibition.