Synthesis,Characterization, and Biological Activities of Pendant Arm‐Pyridyltetrazole Copper(II) Complexes: DNA Binding/Cleavage Activity and Cytotoxic Studies

2‐(1H‐Tetrazol‐5‐yl)pyridine ( L ) has been reacted separately with Me₂NCH₂CH₂Cl?HCl and ClCH₂CH₂OH to yield two regioisomers in each case, N,N‐dimethyl‐2‐[5‐(pyridin‐2‐yl)‐1H‐tetrazol‐1‐yl]ethanamine ( L1 )/N,N‐dimethyl‐2‐[5‐(pyridin‐2‐yl)‐2H‐tetrazol‐2‐yl]ethanamine ( L2 ) and 2‐[5‐(pyridin‐2‐yl)‐1H‐tetrazol‐1‐yl]ethanol ( L3 )/2‐[5‐(pyridin‐2‐yl)‐2H‐tetrazol‐2‐yl]ethanol ( L4 ), respectively. These ligands, L1 – L4 , have been coordinated with CuCl₂?H₂O in 1 : 1 composition to furnish the corresponding complexes 1 – 4 . EPR Spectra of Cu complexes 1 and 3 were characteristic of square planar geometry, with nuclear hyperfine spin 3/2. Single X‐ray crystallographic studies of 3 revealed that the Cu center has a square planar structure. DNA binding studies were carried out by UV/VIS absorption; viscosity and thermal denaturation studies revealed that each of these complexes are avid binders of calf thymus DNA. Investigation of nucleolytic cleavage activities of the complexes was carried out on double‐stranded pBR322 circular plasmid DNA by using a gel electrophoresis experiment under various conditions, where cleavage of DNA takes place by oxidative free‐radical mechanism (OH ^? ). In vitro anticancer activities of the complexes against MCF‐7 (human breast adenocarcinoma) cells revealed that the complexes inhibit the growth of cancer cells. The IC₅₀ values of the complexes showed that Cu complexes exhibit comparable cytotoxic activities compared to the standard drug cisplatin.     

Corrugation Enabled Asymmetrically Ultrastretchable (95%) Monocrystalline Silicon Solar Cells with High Efficiency (19%)

Stretchable solar cells are of growing interest due their key role in realizing many applications such as wearables and biomedical devices. Ultrastretchability, high energy‐efficiency, biocompatibility, and mechanical resilience are essential characteristics of such energy harvesting devices. Here, the development of wafer‐scale monocrystalline silicon solar cells with world‐record ultrastretchability (95%) and efficiency (19%) is demonstrated using a laser‐patterning based corrugation technique. The demonstrated approach transforms interdigitated back contacts (IBC) based rigid solar cells into mechanically reliable but ultrastretchable cells with negligible degradation in the electric performance in terms of current density, open‐circuit voltage, and fill factor. The corrugation method is based on the creation of alternating grooves resulting in silicon islands with different shapes. The stretchability is achieved by orthogonally aligning the active silicon islands to the applied tensile stress and using a biocompatible elastomer (Ecoflex) as a stretchable substrate. The resulting mechanics ensure that the brittle silicon areas do not experience significant mechanical stresses upon asymmetrical stretching. Different patterns are studied including linear, diamond, and triangular patterns, each of which results in a different stretchability and loss of active silicon area. Finally, finite element method based simulation is conducted to study the generated deformation in the different patterned solar cells.     

Investigation of the Effects of the Fenoxaprop-p-Ethyl Herbicide and Salicylic Acid on the Ascorbic Acid and Vitamin B6 Vitamers in Wheat Leaves

Journal of Plant Growth Regulation - Herbicides inhibit plant growth and development by various mechanisms, and oxidative stress is a common plant response to herbicide treatment. In a limited...     

Analysis of stochastic strategies in bacterial competence: a master equation approach

Competence is a transiently differentiated state that certain bacterial cells reach when faced with a stressful environment. Entrance into competence can be attributed to the excitability of the dynamics governing the genetic circuit that regulates this cellular behavior. Like many biological behaviors, entrance into competence is a stochastic event. In this case cellular noise is responsible for driving the cell from a vegetative state into competence and back. In this work we present a novel numerical method for the analysis of stochastic biochemical events and use it to study the excitable dynamics responsible for competence in Bacillus subtilis. Starting with a Finite State Projection (FSP) solution of the chemical master equation (CME), we develop efficient numerical tools for accurately computing competence probability. Additionally, we propose a new approach for the sensitivity analysis of stochastic events and utilize it to elucidate the robustness properties of the competence regulatory genetic circuit. We also propose and implement a numerical method to calculate the expected time it takes a cell to return from competence. Although this study is focused on an example of cell-differentiation in Bacillus subtilis, our approach can be applied to a wide range of stochastic phenomena in biological systems.     

The descending branch of the superficial circumflex artery supplying anteromedial thigh skin

This report presents an extended groin flap design that consists of a conventional skin paddle in the groin region and a vertical extension in the anteromedial thigh region, based on the superficial iliac circumflex artery and an unnamed descending branch, respectively. The inferior branch of the superficial iliac circumflex artery that supplies the thigh extension of the flap, spanning approximately the upper half of the thigh region, was found to originate approximately 2 cm from the origin of the superficial iliac circumflex artery. A total of six free and four local flaps were used in 10 patients with ages ranging from 10 to 60 years (average, 45 years). There were six male and four female patients. The free flaps were required for total facial resurfacing, through-and-through cheek defect, and burn scar contractures and traumatic defects of the lower extremity. The local flaps were used for reconstruction of scrotum defect, trochanteric decubitus ulcer, and lower abdominal skin and fascia defects. All 10 flaps survived completely. The groin flap with anteromedial thigh extension offers the following advantages: (1) it is very easy and quick to elevate; (2) a significantly increased volume of tissue is available for reconstruction, based on one axial vessel and being completely reliable; (3) the flap offers two skin paddles that are independently mobile; (4) there is no need for positional change and a two-team approach is possible; and (5) it can be raised as a vertical skin island only. The authors conclude that the groin flap with anteromedial thigh extension is a useful modification for reconstruction of both distant and local defects.     

Serum Levels of Zinc,Copper, Iron,Cobalt, Magnesium,and Selenium Elements in Children Diagnosed with <Emphasis Type="Italic">Giardia Intestinalis</Emphasis> and <Emphasis Type="Italic">Enterobiosis Vermicularis</Emphasis> in Hatay,Turkey

The intestinal parasites are noted to be an important health problem in Turkey as similarly reported in the globe. The aim of this study was to investigate the changes in total content of essential elements, namely, zinc, iron, copper, cobalt, magnesium, and selenium, in children infected with intestinal parasites aged between 6 and 12 years inhabiting in Hatay Province, Turkey. These essential elements were measured in the children/patient who was positive for intestinal parasites, Giardia intestinalis and Enterobius vermicularis. Scores were obtained from the positive study group (SG), and their age matched the healthy children control group (CG). Serological levels of zinc, iron, copper, cobalt, magnesium, and selenium were analyzed by Varian Liberty Series II inductively coupled plasma atomic emission spectrometer (ICP-AES). The mean magnesium concentrations were found to be statistically different at 95% confidence interval level between study groups. As a result of this study, selenium was found to be uncorrelated with all other elements examined; whereas, copper was observed to have statistically significant correlations with cobalt, magnesium, and zinc. In addition, cobalt-magnesium, cobalt-zinc, and magnesium-zinc metal pairs were found to have statistically significant correlations based on study findings.