Focusing and imaging with increased numerical apertures through multimode fibers with micro-fabricated optics

The use of individual multimode optical fibers in endoscopy applications has the potential to provide highly miniaturized and noninvasive probes for microscopy and optical micromanipulation. A few different strategies have been proposed recently, but they all suffer from intrinsically low resolution related to the low numerical aperture of multimode fibers. Here, we show that two-photon polymerization allows for direct fabrication of micro-optics components on the fiber end, resulting in an increase of the numerical aperture to a value that is close to 1. Coupling light into the fiber through a spatial light modulator, we were able to optically scan a submicrometer spot (300 nm FWHM) over an extended region, facing the opposite fiber end. Fluorescence imaging with improved resolution is also demonstrated.Comment: 5 pages, 3 figure

Impact of obesity on semen quality in men of infertile couples: a cross-sectional study in a tertiary care centre

Background: Obesity is an emerging problem worldwide. The aim of the study was to determine the association of Body mass index and central obesity with semen parameters in men of infertile couples.Methods: This was a descriptive study conducted in a population that included 219 men of infertile couples who attended the infertility clinic. A detailed history was taken from the participants and measurements of height, weight, waist circumference and hip circumference were done by standard methods. General, systemic and urogenital tract examinations were done. The participants were advised to collect semen specimens and semen was analyzed and various semen parameters were noted based on WHO criteria 2010.Results: Among the overweight and obese men, 12.7% and 20.5% were oligozoospermic respectively. Asthenozoospermia was seen in 21.2% and 25% of overweight and obese men. Among men with waist circumference ≥102 cm, 14.3% had oligozoospermia and 35.7% of men had asthenozoospermia. Around 12.2% of men with a Waist-hip ratio >0.9 had oligozoospermia and 19.8% of them had asthenozoospermia.Conclusions: A significant negative association was seen between WHR and sperm concentration, total sperm count, total progressive motility and total motility were seen to be removed. There was no significant association between WC, BMI and sperm concentration, total sperm count, total progressive motility, and total motility

In Vitro Screening of Cytotoxic, Antimicrobial and Antioxidant Activities of Clinacanthus nutans (Acanthaceae) leaf extracts

Purpose: To evaluate the in vitro cytotoxic, antioxidant and antimicrobial activities of Clinacanthus nutans extracts and semi-fractions.Method: The plant was subjected to cold solvent extraction to produce petroleum ether, ethyl acetate and methanol crude extracts, followed by isolation using bioassay-guided fractionation. The crude extracts (0.2 to 10.0 mg/ml) were tested against HeLa and K-562 cell lines using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and antioxidant activity using 1, 1-diphenyl-2- picrylhydrazyl (DPPH) assay. Furthermore, fractions isolated from ethyl acetate leaf extract (0.02 to10.0 mg/ml) were tested against Bacillus cereus (ATCC11778), Escherichia coli (ATCC25922), Salmonella enterica Typhimurium (ATCC14028) and Candida albicans (ATCC10231) using minimum inhibitory concentration (MIC) and minimum bactericidal or fungicidal (MBC/MFC) assays.Results: Petroleum ether extracts demonstrated the strongest cytotoxic activity against HeLa and K-562 cells with IC50 of 18.0 and 20.0 ìg/mL, respectively. Petroleum ether extracts also displayed the highest radical scavenging activity of 82.00 ± 0.02 %, compared with ascorbic acid and á-tocopherol corresponding values of 88.7 ± 0.0 and 86.6 ± 0.0 %, respectively. In MIC assay, all the crude extracts and fractions showed inhibition against all tested microorganisms. Fraction 7 displayed the lowest MIC and MBC/MFC values against B. cereus and C. albicans at 1.39 mg/ml, respectively. Ampicillin and amphotericin B displayed MIC value of 1.3 mg/ml.Conclusion: The bioactive compounds from C. nutans are potential  cytotoxic, antimicrobial and antioxidant agents.Keywords: Clinacanthus nutans, Cytotoxic, Antioxidant, Antimicrobia

TWO PHASE CFD FLOW ANALYSIS OF R134a AND R1234yf REFRIGERANTS AND ITS EFFECT ON COOLING PERFORMANCE IN AN AUTOMOBILE HVAC EVAPORATOR CORE

The purpose of this research is to conduct a two-phase fluid analysis and simulation for examining the influence of refrigerant (R134a/R1234yf) properties on cooling performance of an automobile HVAC (Heating, Ventilation and Air Conditioning) evaporator core and compare their performances. In this research, streamline deviation, static pressure, velocity magnitude, pressure co-efficiency, Reynolds number and turbulent kinetic energy play a key role in the comparison of the refrigerants R1234yf and R134a two-phase fluids. Subsequently, it was found that R134a properties were better towards the cooling performance of an automobile HVAC evaporator core.&nbsp

Ethnobotany, Phytochemistry and Pharmacology of \u3cem\u3eMussaenda\u3c/em\u3e Species (Rubiaceae)

The genus Mussaenda is an important source of medicinal natural products, particularly iridoids, triterpenes and flavonoids. The purpose of this paper is to cover the more recent developments in the ethnobotany, pharmacology and phytochemistry of this genus. The species in which the largest number of compounds has been identified is Mussaenda pubescens. Pharmacological studies have also been made, however, of other species in this genus. These lesser known plants of the genus are described here according to their cytotoxicity, anti-inflammatory, antiviral, antioxidant and antibacterial properties. The information given here is intended to serve as a reference tool for practitioners in the fields of ethnopharmacology and natural products chemistry

Identification of Beryllium Hydride Isotopomer Lines in Sunspot Umbral Spectra

A high resolution spectrum of FTS sunspot umbra of NSO/Kitt Peak was used to conduct a search for the molecular absorption lines due to BeH, BeD and BeT isotopomers. Analysis led to estimates of identification of the molecular lines of bands A - X (0,0), (1,1) and (2,2) for BeH, A - X (0,0), (1,1), (2,2) and (3,3) for BeD and of A - X (0,0), (1,1) and (2,2) for BeT. Among the identified lines, those which are well resolved were selected for measurements to calculate equivalent widths. The values of effective rotational temperature T were estimated for bands A - X(1,1) and (2,2) of BeH, A - X(1,1) of BeD and A - X(2,2) of BeT to be 4228K, 4057K, 3941K and 3243K respectively

Jet: Multilevel Graph Partitioning on GPUs

The multilevel heuristic is the dominant strategy for high-quality sequential and parallel graph partitioning. Partition refinement is a key step of multilevel graph partitioning. In this work, we present Jet, a new parallel algorithm for partition refinement specifically designed for Graphics Processing Units (GPUs). We combine Jet with GPU-aware coarsening to develop a $k$-way graph partitioner. The new partitioner achieves superior quality when compared to state-of-the-art shared memory graph partitioners on a large collection of test graphs.Comment: Submitted as a non-archival track paper for SIAM ACDA 202

Simulation of a dipeptide Boc-Ile-Ile-NHMe as a drug carrier

Reverse micelles are discrete nanoscale particles composed of a water core surrounded by surfactant. In this current study the the self assembling properties of the dipeptide Boc-Ile-Ile-NHMe in chloroform to form a stable micelle at various temperatures ranging from 200 to 350 Kelvin has been analysed using insilico methods. The computational analysis was carried out using the steepest descent algorithm, a minimization tool used to study the protein energy level in insilco and it was compared with the thermodynamic parameters determined experimentally. Such reverse micelles finds a vast area of application one of which is drug delivery in nanotechnology. The present dipeptide is shown to carry drugs by insilico methods.   Key words: Reverse micelles, tetra peptide, minimization, drug delivery, nanotechnology