Sgr A* ``Visual Binaries'': A Direct Measurement of the Galactocentric Distance

We present a new geometrical method for measuring the distance to the Galactic center (R_0) by solving for the Keplerian orbit of individual stars bound to the black hole associated with the Sgr A* from radial velocity and proper motion measurements. We identify three stars to which the method may be applied, and show that 1-5 % accuracy of R_0 can be expected after 15 years of observing, and 0.5-2 % after 30 years of observing, depending on what the orbital parameters of these three stars turn out to be. Combining the measurements of the three stars with favorable orbital parameters leads to even more precise values. In the example that we present, such combined solution yields 4 % accuracy already by the year 2002. All these estimates assume that annual position measurements will continue to be made with the 2 mas precision recently reported by Ghez et al. The precision of the distance measurement is relatively insensitive to the radial velocity errors, provided that the latter are less than 50 km/s. Besides potentially giving an estimate of R_0 that is better than any currently in use, the greatest advantage of this method is that it is free from systematic errors.Comment: Submitted to ApJ, 14 pages, 8 figure

Note on improvement precision of recursive function simulation in floating point standard

An improvement on precision of recursive function simulation in IEEE floating point standard is presented. It is shown that the average of rounding towards negative infinite and rounding towards positive infinite yields a better result than the usual standard rounding to the nearest in the simulation of recursive functions. In general, the method improves one digit of precision and it has also been useful to avoid divergence from a correct stationary regime in the logistic map. Numerical studies are presented to illustrate the method.Comment: DINCON 2017 - Conferencia Brasileira de Dinamica, Controle e Aplicacoes - Sao Jose do Rio Preto - Brazil. 8 page

Coherent control of nanomagnet dynamics via ultrafast spin torque pulses

The magnetization orientation of a nanoscale ferromagnet can be manipulated using an electric current via the spin transfer effect. Time domain measurements of nanopillar devices at low temperatures have directly shown that magnetization dynamics and reversal occur coherently over a timescale of nanoseconds. By adjusting the shape of a spin torque waveform over a timescale comparable to the free precession period (100-400 ps), control of the magnetization dynamics in nanopillar devices should be possible. Here we report coherent control of the free layer magnetization in nanopillar devices using a pair of current pulses as narrow as 30 ps with adjustable amplitudes and delay. We show that the switching probability can be tuned over a broad range by timing the current pulses with the underlying free-precession orbits, and that the magnetization evolution remains coherent for more than 1 ns even at room temperature. Furthermore, we can selectively induce transitions along free-precession orbits and thereby manipulate the free magnetic moment motion. We expect this technique will be adopted for further elucidating the dynamics and dissipation processes in nanomagnets, and will provide an alternative for spin torque driven spintronic devices, such as resonantly pumping microwave oscillators, and ultimately, for efficient reversal of memory bits in magnetic random access memory (MRAM).Comment: 4 pages, 3 figures, submitted to Nature Physic

PREPARATION OF BUDESONIDE-PECTIN BEADS USING THE PERISTALTIC PUMP

Objective: To formulate and evaluate budesonide-pectin beads using novel assembly with a peristaltic pump.Methods: The prepared budesonide-pectin dispersion was added to calcium chloride solution with the help of assembly. Provided at least 2 h for hardening and dried at 60 °C for 3 h. Assembly was assembled with the use of a peristaltic pump, polymeric solution reservoir, hose, needle, magnetic stirrer, gelling bath. One side of hose was dipped in pectin solution container and another side was passed through the peristaltic pump and connected to the needle. Peristaltic pump produced pumping of pectin solution through the hose. Needles with variable diameters are available. The gelling bath was kept on magnetic stirrer to keep prepared beads in motion, which helped to provide new surface and sufficient reaction time and helped to avoid agglomeration. There were 10 different batches with different process parameters prepared. Production yield, the diameter of beads, swelling index, and in vitro budesonide dissolution in phosphate buffer pH 7.4 after 5 h was determined.Results: There was a significant difference between selection of process parameter among the batches (p = 0.049, q = 6.11). As nozzle diameter was increased, percentage yield was decreased (p = 0.0038, q>5.98). However, if hardening time was decreased percentage release was increased (p = 0.0361, q>5.98).Conclusion: The novel assembly for bead generation had developed a uniform, spherical shaped, and smooth surfaced beads

Contaminación fúngica de frutos secos de vid y detección de ocratoxina en jugo de uva enDuhok, Iraq

Introduction: Dried vine fruits (raisins) and their juice are widely consumed by human as a diet. Raisins have been shown highly contaminated with ochratoxin A (OTA) and OTA-producing fungi. Ochratoxin A is a potent nephrotoxic and carcinogen to human and animals. Materials and Methods: Dried vine fruit samples was obtained from local shops for fruit juice and soft drinks in Duhok province. Two different media, Dichloran R ose Ben gal Chloromphenicol Agar (DRBC) and Dichloran 18 % Glycerol Agar (DG-18) was used for the counting and isolation of fungi from dried vine fruits. Grape juice were prepared from dried vine fruit after blending with water in a commercial blender. Natural contamination with ochratoxin A was detected by LC-MS/MS technique. Results and Discussion: All samples confirmed to be contaminated with fungi with various degrees. A total of 19 filamentous genera of fungi as well to Yeasts and non sporulation mycelium was detected. Predominant genera detected on both media were Aspergillus and Penicillium. Detected value of ochratoxn A in juices obtained from dried vine fruits was between 0.37 ng/ml to 1.85 ng/ml. Samples contaminated with ochratoxin A were associated withAspergillus carbonarius, A. niger aggregate, A. sclerotium, A. ochraceus, and Penicillum verrucosum. Conclusion: Dried vines fruit were highly contaminated with a broad spectrum of filamentous fungi. Black aspergilli were the most detected species from samples naturally contaminated with ochratoxin

Diverse Glycosides from Gardenia latifolia with Antiviral Activity and Chemosystematic Significance

Several influenza pandemics have impacted our life, each with variable prevalence and severity. In a search for natural antivirals, further phytochemical investigation of Gardenia latifolia Aiton, Rubiaceae, was conducted. As a result, five structurally diverse glycosides were isolated, offering valuable chemotaxonomic data. Using the crystal violet technique, three isolates, canthoside C, (6R,7S,8S)-7α-[(β-d-glucopyranosyl) oxy] lyoniresinol, and ecdysanrosin A, were evaluated for their anti-influenza A (H1N1) activities. Based on previously reported anti-inflammatory activity of the guaiane class, we investigated the inhibitory effect of (1R,7R,8S,10R)-7,8,11-trihydroxy-guai-4-ene-3-one 8-O-β-d-glucopyranoside, a rare guaiane sesquiterpene glucoside, on inducible nitric oxide (NO) production by Griess assay. Regarding antiviral assay, canthoside C was the most active. It considerably inhibited H1N1 infectivity at an IC50 value of 10.93 µg/ml, showing a selectivity index (SI) of 12.88, compared with acyclovir as a standard. Besides, ecdysanrosin A displayed a moderate selective antiviral activity with an IC50 value of 28.03 µg/ml. Considering their low cytotoxicity on the host cells, canthoside C and ecdysanrosin A have additional merit as potential antiviral agents. Despite the claimed anti-inflammatory activity of guaianes, (1R,7R,8S,10R)-7,8,11-trihydroxy-guai-4-ene-3-one 8-O-β-d-glucopyranoside showed a limited anti-inflammatory activity. [Figure not available: see fulltext.

MicroRNA-377 expression level as a marker of nephropathy in Type 2 diabetes mellitus

Background: Diabetic nephropathy is one of the most dangerous complications of diabetes mellitus. To prevent these complications in diabetic patients monitoring of patients is a must. In last decades many authors were trying to investigate molecular biomarker to detect patients who are at risk. MicroRNA-377 is one of the promising biomarkers for prediction of diabetic nephropathy. Objective: This study aimed to investigate the role of miRNA-377 as early predictor of diabetic nephropathy in patients with type 2 diabetes mellitus.Patients and methods: Seventy five patients with type 2 diabetes and 25 healthy control participants are enrolled in a case-control study. Clinical evaluation, and laboratory investigations including fasting plasma glucose, serum creatinine, fasting lipid profile, glycosylated hemoglobin, estimated glomerular filtration rate (eGFR) and albumin creatinine ratio, The expression of serum miRNA-377 was measured via quantitative real-time-polymerase chain reaction (qRT-PCR). Results: Expression of miR-377 could differentiate diabetic patients from healthy control as the expression of miR-377 was significantly higher in overall T2DM patients than in the healthy control (2.5 fold change, P<0.001), and was progressively increased in the normoalbuminuric group and further increased in the microalbuminuric and macroalbuminuric groups (1.92, 2.76, 3.38 fold change respectively, P<0.001). MiR-377 expression levels were positively correlated with diabetes duration, fasting plasma glucose, HbA1C, total cholesterol, LDL-C, triglycerides, creatinine and ACR, while miR-377 expression levels were significantly negatively correlated with HDL-C and eGFR.Conclusions: MiR-377 might act as a promising biomarker for prediction of development of diabetic nephropathy in type 2 diabetes patients

Temperature dependent asymmetry of the nonlocal spin-injection resistance: evidence for spin non-conserving interface scattering

We report nonlocal spin injection and detection experiments on mesoscopic Co-Al2O3-Cu spin valves. We have observed a temperature dependent asymmetry in the nonlocal resistance between parallel and antiparallel configurations of the magnetic injector and detector. This strongly supports the existence of a nonequilibrium resistance that depends on the relative orientation of the detector magnetization and the nonequilibrium magnetization in the normal metal providing evidence for increasing interface spin scattering with temperature.Comment: 5 pages, 4 figures, accepted for publication in PRL, minor corrections (affiliation, acknowledgements, typo