Direct observation of a hydrophobic bond in loop-closure of a capped (-OCH2CH2-)n oligomer in water

The small r variation of the probability density P(r) for end-to-end separations of a -CH2CH3 capped (-OCH2CH2-)n oligomer in water is computed to be closely similar to the CH4 ... CH4 potential of mean force under the same circumstances. Since the aqueous solution CH4 ... CH4 potential of mean force is the natural physical definition of a primitive hydrophobic bond, the present result identifies an experimentally accessible circumstance for direct observation of a hydrophobic bond which has not been observed previously because of the low solubility of CH4 in water. The physical picture is that the soluble chain molecule carries the capping groups into aqueous solution, and permits them to find one another with reasonable frequency. Comparison with the corresponding results without the solvent shows that hydration of the solute oxygen atoms swells the chain molecule globule. This supports the view that the chain molecule globule might have a secondary effect on the hydrophobic interaction which is of first interest here. The volume of the chain molecule globule is important for comparing the probabilities with and without solvent because it characterizes the local concentration of capping groups. Study of other capping groups to enable X-ray and neutron diffraction measurements of P(r) is discussed.Comment: 4 pages, 3 figure

DEVELOPMENT AND EVALUATION OF ANTIDIABETIC POLYHERBAL TABLET USING MEDICINAL PLANTS OF TRADITIONAL USE

Objective: The aim of the present study is to develop and evaluate poly herbal tablet prepared for management of diabetes with enhanced disintegration time. Methods: The polyherbal extract prepared using methanolic extract of selected traditionally used medicinal plants such as Adenanthera pavonina, Kigelia africana, Parkia biglandulosa and Syzygium jambose (1:1:1:2) was evaluated in the alloxan monohydrate induced diabetic rat model. The polyherbal tablets were prepared by wet granulation method with excipients microcrystalline cellulose, dicalcium phosphate dehydrate and sodium starch glycolate. After preformulation studies tablets were evaluated by using weight variation, hardness, friability and disintegration time. The diabetic rats treated with polyherbal extract were compared with the diabetic control rats group. Results: Positive results were obtained in the observed parameters, thus favoring the use of the plants. Pre-formulation study revealed that all the evaluated parameters were found to be within the acceptable limits. The weight variation of the formulated tablets was 1.43 % RSD. The disintegration time of the formulations was found to be 9.50 minutes. The tablets also underwent accelerated stability over the period of three months. No marked changes were observed in all the parameters evaluated during three months of accelerated stability study. Conclusion: Laboratory-scale preparation of polyherbal tablet can lead to new powerful and stable oral dosage formulations for diabetes mellitus and lighten the synergistic area of ​​action of herbs

Photoinduced Electron-transfer Along Alpha-helical And Coiled-coil Metallopeptides

A peptide-based electron-transfer system has been designed in which the specific positions of redox-active metal complexes appended to either an a-helix, or an a-helical coiled-coil, can be reversed to test the effect of the helix dipole in controlling photoinduced electron-transfer rates. Two 30-residue apopeptides were prepared having the following sequences: (1) Ac-K-(IEALEGK)(ICALEGK)(IEALEHK)-(IEALEGK)-G-amide, and (II) Ac-K-(IEALEGK)(IHALEGK)-(IEALECK)(IEALEGK)-G-amide. Each apopeptide was reacted first with [Ru(bpy)(2)(phen-ClAc)](2+), where bpy = 2,2\u27-bipyridine and phen-ClAc = 5-chloroacetamido-1,10-phenanthroline, to attach the ruthenium polypyridyl center to the cysteine side-chain of the polypeptide. The isolated products were then reacted with [Ru(NH3)(5)(H2O)](2+) to yield the binuclear electron-transfer metallopeptides ET-I and ET-II. In these systems, electron-transfer occurred from the photoexcited ruthenium polypyridyl donor to the pentammine ruthenium (111) acceptor such that the electron-transfer occurred toward the negative end of the helix dipole in ET-I, and toward the positive end in ET-II. Circular dichroism spectroscopy showed that both peptides exist as dimeric alpha-helical coiled-coils in 100 mM phosphate buffer at pH 7, and as monomeric a-helices in the lower dielectric solvents 2,2,2-trifluoroethanol, and a 1:1 (v/v) mixture of CH2Cl2 and 2,2,2-trifluoroethanol. The peptides were predominately (i.e., 65-72%) alpha-helical in these solvents. The emission lifetime behavior of ET-I was seen to be identical to that of ET-II in each of the three solvents: no evidence for directional electron-transfer rates was observed. Possible reasons for this behavior are discussed

Wound Healing Evaluation of Some Herbal Formulations Containing Curcuma Longa and Cynodon Dactalon Extract

The wound healing effect of herbal cream formulated with Curcuma longa, and Cynodon dactylon embedded in different ointment bases (anionic, cationic and non-ionic) has been evaluated in vivo using the incision, excision and dead space tissue wound models, on Swiss wister rat. Curcuma longa, and Cynodon dactylon was extracted using Pet ether (60-800C ), chloroform, ethanol, methanol and water. The  methanolic  extract formulated as herbal preparations. The herbal preparations were used to treat wounds inflicted on experimental  Swiss wister rat. The wound healing effects of the formulations were compared to that of a standard antibiotic. In all cases, there was a progressive decrease in wound area with time, indicating an efficacy of the formulations in healing the induced wounds. By the 14th day, the formulation  containing 100 mg/g of Curcuma longa, and Cynodon dactylon in cationic base showed 100 % healing. The wound areas in the animals treated with the standard antibiotic, showed a 100% healing by the 17 th day, indicating that the plant extract, at that given concentration, had a better wound healing property

Simulation of heavy rainfall over Mumbai on 26 july 2005 using high resolution icosahedral gridpoint model GME

In this paper an attempt has been made to simulate the exceptionally heavy rainfall event over Mumbai (Bombay) on 26 July 2005. Santa Cruz observatory near the International Airport of Mumbai recorded 944.2 mm of rainfall between 0300 UTC of 26 July 2005 and 0300 UTC of 27 July 2005 breaking all previous records. Some nearby places also recorded very heavy rainfall. Consequently, a deluge flooded the city and life in Mumbai came to a standstill. Mesoscale models or regional models are normally used to simulate such a small scale phenomenon. The model used in this paper to simulate the rainfall is the operational global numerical weather prediction model (GME) developed by the Deutscher Wetterdienst, The German Weather Service. Using European Center for Medium range Weather Forecast-ECMWF at T511 L91 data as the initial condition for the GME model, 24 hours accumulated precipitation has been computed. The model has a horizontal resolution of 40 km with 40 vertical levels and time step of 133s. The computed rainfall agrees reasonably well with the actual precipitation. The localized heavy rainfall might have occurred over Mumbai possibly due to several factors such as: well-marked low pressure over Orissa and adjoining Jharkhand with associated cyclonic circulation extending up to mid-troposheric level; off-shore trough on the west coast of India; low level jet over the peninsular India; intense convection and orographic lifting and interactions among these meteorological phenomena of different scales

Measurement and Modeling of Magnetic Hysteresis in the LHC Superconducting Correctors

The Large Hadron Collider, now under construction at CERN, relies heavily on superconducting magnets for its optics layout: besides the main magnets, almost all the correcting magnets are superconducting. Along with clear advantages, this brings about complications due to the effects of persistent currents in the superconducting filaments. Corrector magnets that trim key beam parameters or compensate field errors of the main magnets (among others those due to hysteresis), are in their turn hysteretic. In this paper we present the measured magnetic hysteresis and its possible influence on accelerator operation, with particular reference to realtime compensation of dynamic effects in the main magnets, and reproducibility issues between runs. The modeling strategy as a function of the required accuracy is discussed, and two examples are presented

Acute and subchronic toxicity study of Tamra Bhasma (incinerated copper) prepared with and without Amritikarana

AbstractBackgroundTamra Bhasma (TB) is one among herbo-metallic preparations extensively used in routine ayurvedic practice. In the present era, Bhasma preparations used in ayurvedic system of medicines are always under stern observations for containing heavy metals which may raise the question of safety aspect.ObjectiveIn the present study, TB prepared with and without Amritikarana was subjected to toxicity study to ascertain the role of Amritikarana on safety profile of TB in rats.Materials and methodsBoth the samples of TB were administered to rats for 28 consecutive days at the doses of 5.5, 27.5, and 55 mg/kg. The effects of both drugs were assessed on ponderal changes, hematological, serum biochemical, and histopathology of various organs.ResultsResults showed that both the samples of TB did not produce any sign and symptoms of toxicity at therapeutic dose level (5.5 mg/kg) and therapeutic equivalent dose (TED) × 5 (27.5 mg/kg) while at higher dose of TED × 10 (55 mg/kg) TB has mild toxicity in liver, kidney, heart, and thymus on repeated administration for 28 days in rats. The sample without Amritikarana has more magnitude of toxicity than the sample with Amritikarana.ConclusionFrom the present study, it is concluded that TB with Amritikarana was found to be relatively safer than TB without Amritikarana at different dose levels in rats and hence suggest for safely use in humans at therapeutic dose level. It proves the role of Amritikarana in the preparation of TB

Self-generated magnetic flux in YBa2_2Cu3_3O7−x_{7-x} grain boundaries

Grain boundaries in YBa$_2$Cu$_3$O$_{7-x}$ superconducting films are considered as Josephson junctions with a critical current density $j_c(x)$ alternating along the junction. A self-generated magnetic flux is treated both analytically and numerically for an almost periodic distribution of $j_c(x)$. We obtained a magnetic flux-pattern similar to the one which was recently observed experimentally.Comment: 7 pages, 3 figure

Pedestrian recognition and obstacle avoidance for autonomous vehicles using raspberry Pi

© Springer Nature Switzerland AG 2020. The aim of this paper is twofold: firstly, to use ultrasonic sensors to detect obstacles and secondly to present a comparison of machine learning and deep learning algorithms for pedestrian recognition in an autonomous vehicle. A mobility scooter was modified to be fully autonomous using Raspberry Pi 3 as a controller. Pedestrians were initially simulated by card board boxes and further replaced by a pedestrian. A mobility scooter was disassembled and connected to Raspberry Pi 3 with ultrasonic sensors and a camera. Two computer vision algorithms of histogram of oriented gradients (HOG) descriptors and Haar-classifiers were trained and tested for pedestrian recognition and compared to deep learning using the single shot detection method. The ultrasonic sensors were tested for time delay for obstacle avoidance and were found to be reliable at ranges between 100 cm and 500 cm at small angles from the acoustic axis, and at delay periods over two seconds. HOG descriptor was found to be a superior algorithm for detecting pedestrians compared to Haar-classifier with an accuracy of around 83%, whereas, deep learning outperformed both with an accuracy of around 88%. The work presented here will enable further tests on the autonomous vehicle to collect meaningful data for management of vehicular cloud