Two-dimensional Stiefel-Whitney insulators in liganded Xenes

Two-dimensional (2D) Stiefel-Whitney insulator (SWI), which is characterized by the second Stiefel-Whitney class, is a class of topological phases with zero Berry curvature. As an intriguing topological state, it has been well studied in theory but seldom realized in realistic materials. Here we propose that a large class of liganded Xenes, i.e., hydrogenated and halogenated 2D group-IV honeycomb lattices, are 2D SWIs. The nontrivial topology of liganded Xenes is identified by the bulk topological invariant and the existence of protected corner states. Moreover, the large and tunable bandgap (up to 3.5 eV) of liganded Xenes will facilitate the experimental characterization of the 2D SWI phase. Our findings not only provide abundant realistic material candidates that are experimentally feasible but also draw more fundamental research interest towards the topological physics associated with Stiefel-Whitney class in the absence of Berry curvature.

Ameliorative Effects of Fenugreek Seeds and Curcumin on Hematotoxicity induced by Nicotine in Male Albino Rats

The present study aimed to investigate the ameliorative effects of fenugreek seeds and curcumin on hematotoxicity induced by nicotine in male albino rats. 30 male F-344/NHsd Fischer rats, weighing from 180 to 200g were used in the present study. The animals were divided into five groups (6 rats for each); Group I (control group), Group II (nicotine treated group), Group III (nicotine/fenugreek seeds co-administered), Group IV (nicotine/curcumin co-administered), and Group V (nicotine/curcumin& fenugreek seeds co-administered). At the end of the experimentation and 24 hours after the last dose, all animals were anaesthetized with ether and blood samples were collected by heart puncture. The samples were collected in clean dry tubes containing the anticoagulant substance EDTA and used for the hematological studies. The results showed that the animals treated with nicotine for 4 weeks showed a significant decrease in RBCs count, hemoglobin concentration, hematocrit value, MCH, MCHC, and platelets count, and increased MCV and WBCs count as compared to the control group. Co-administration of nicotine with fenugreek and/or curcumin caused improvement in all hematological parameters when compared with nicotine group. It can be concluded that nicotine had a strong effect on the hematological parameters. The ingestion of fenugreek and/or curcumin prevent the hematoxicity induced by nicotine. The current study suggests that fenugreek and curcumin may be useful in combating free radical-induced hematotoxicity induced by nicotine.

Photosensitive Schottky Barrier Diode Based on Cu/p-SnSe Thin Film Fabricated by Thermal Evaporation

Tin Selenide (SnSe), a group IV-VI compound semiconductor material is used to fabricate various solid state devices such as memory switching devices, P-N junction diodes, Schottky barrier diodes, etc. In...

Диэлектрические и оптические свойства кубических монокристаллов SiC, GeC и SnC: модельные оценки

Within the scope of the Harrison’s bond orbital model analytical expressions of the high- and low-frequency dielectric susceptibilities and dielectric constants, linear electrooptical coefficient, photoelastic constants and pressure dependences of the dielectric constants are obtained for the cubic carbides of the group IV elements.

The Superior Outcome of Collagen Nanosilver in Increasing Macrophage and Collagen on Deep Dermal Burn Wound Healing

AIM: This study aims to prove the superior outcome of collagen nanosilver in increasing macrophage and collagen on deep dermal burn wound healing. METHODS: This study was a randomized control trial design. All animals used were male Sprague Dawley rats aged 12–14 weeks old and weighed about 200–250 g. Each rat gets four site injuries and is given treatments. The treatment group includes: I (negative control using NaCl 0.9%), II (positive control using silver sulfadiazine cream), III (treatment with nanosilver collagen cream 1%), and IV (treatment with collagen nanosilver cream 2%). Macrophages counts were assessed using IHC F40/80 and collagen density was assessed using Masson’s trichrome staining. RESULTS: Macrophage on day 6 showed a significant difference as seen in group III and group IV. A significant difference was also obtained between macrophage on day 3 and day 6 from group IV, likewise between collagen between day 3 and day 6 from group III and IV. Collagen nanosilver acts as an antimicrobial and anti-inflammatory agent by increasing the mechanism of activation and migration of macrophages to the site of injury. Moreover, this formula modulated the collagen deposition, which forms the tissue fibers which ultimately provide a conducive environment for wound healing. CONCLUSION: Collagen nanosilver has a superior outcome in the increasing macrophage cell count and collagen density of deep dermal burn wound healing.

An Experimental Study on Timing in Tracheal Stenosis Surgery

Background TNF-α, IL-6, and TGF-β are important bio mediators of the inflammatory process. This experimental study has investigated inflammatory biomarkers' efficacy to determine the appropriate period for anastomosis surgery in tracheal stenosis cases. Methods First, a pilot study was performed to determine the mean stenosis ratio (SR) after the surgical anastomosis. The trial was planned on 44 rats in four groups based on the pilot study's data. Tracheal inflammation and stenosis were created in each rat by using micro scissors. In rats of groups I, II, III, and IV, respectively, tracheal resection and anastomosis surgery were applied on the 2nd, 4th, 6th, 8th weeks after the damage. The animals were euthanized 8 weeks later, followed by histopathological assessment and analysis of TNF-α, IL-6, and TGF-β as biochemical markers. Results Mean SR of the trachea were measured as 21.9 ± 6.0%, 24.1 ± 10.4%, 25.8 ± 9.1%, and 19.6 ± 9.2% for Groups I to IV, respectively. While Group III had the worst SR, Group IV had the best ratio (p = 0.03). Group II had the highest values for the biochemical markers tested. We observed a statistically significant correlation between only histopathological changes and TNF-α from among the biochemical markers tested (p = 0.02). It was found that high TNF-α levels were in a relationship with higher SR (p = 0.01). Conclusion Tracheal anastomosis for post-traumatic stenosis is likely to be less successful during the 4th and 6th weeks after injury. High TNF-α levels are potentially predictive of lower surgical success. These results need to be confirmed by human studies.

Hemoglobin A1c Threshold for Reduction in Bone Turnover in Men With Type 2 Diabetes Mellitus

BackgroundEmerging data suggest that type 2 diabetes mellitus (T2D) is associated with an increased risk for fractures despite relatively normal or increased bone mineral density (BMD). Although the mechanism for bone fragility in T2D patients is multifactorial, whether glycemic control is important in generating this impairment in bone metabolism remains unclear. The purpose of our study is to identify a hemoglobin A1c (A1c) threshold level by which reduction in bone turnover begins in men with T2D.MethodA cross-sectional analysis of baseline data was obtained from 217 men, ages 35–65, regardless of the presence or absence of hypogonadism or T2D, who participated in 2 clinical trials. The following data were obtained: A1c by HPLC, testosterone and estradiol by LC/MS, bone turnover markers Osteocalcin [OC], C-terminal telopeptide [CTx], and sclerostin by ELISA, and BMD by DXA. Patients were grouped into 4 categories based of A1c (group I: <6%, group II: 6.0–6.4%, group III: 6.5–6.9%, and group IV: ≥7%). Threshold models were fit to the data using nonlinear regression and group comparisons among the different A1c categories performed by ANOVA.ResultsThreshold model and nonlinear regression showed an A1c cut-off of 7.0, among all choices of A1cs, yields the least sum of squared errors. A comparison of bone turnover markers revealed relatively lower OC (p = 0.002) and CTx (p = 0.0002) in group IV (A1c ≥7%), compared to the other groups. An analysis of men with T2D (n = 94) showed relatively lower OC (p=0.001) and CTx (p=0.002) in those with A1c ≥7% compared to those with <7%, respectively. The significance between groups persisted even after adjusting for medications and duration of diabetes.ConclusionAn analysis across our entire study population showed a breakpoint A1c level of 7% or greater is associated with lower bone turnover. Also in men with T2D, an A1c ≥7% is associated with low bone turnover.