Refractive index sensing setup based on a taper and an intrinsic micro Fabry-Perot interferometer

In this work, a refractive index sensor setup based on a biconically tapered fiber (BTF) concatenated to an intrinsic all-fiber micro Fabry-Perot interferometer (MFPI) is presented. Here, the power of the MFPI spectral fringes decreases as the refractive index interacts with theevanescent field of the BTF segment. Furthermore, it is demonstrated that the RI sensitivity can be enhanced by bending the BTF segment.Finally, it is shown that by using this sensing arrangement, at ~1.53 µm wavelength, it is possible to detect refractive index changeswithin the measurement range of 1.3 to 1.7 RIU, with a sensitivity of 39.92 dB/RIU and a RI resolution of 2.5 x 10^-3 RIU with a curvature of C = 18.02 m^-1

Vaccines against Tuberculosis: Where Are We and Where Do We Need to Go?

In this review we discuss recent progress in the development, testing, and clinical evaluation of new vaccines against tuberculosis (TB). Over the last 20 years, tremendous progress has been made in TB vaccine research and development: from a pipeline virtually empty of new TB candidate vaccines in the early 1990s, to an era in which a dozen novel TB vaccine candidates have been and are being evaluated in human clinical trials. In addition, innovative approaches are being pursued to further improve existing vaccines, as well as discover new ones. Thus, there is good reason for optimism in the field of TB vaccines that it will be possible to develop better vaccines than BCG, which is still the only vaccine available against TB

Effects of Anacetrapib in Patients with Atherosclerotic Vascular Disease

BACKGROUND: Patients with atherosclerotic vascular disease remain at high risk for cardiovascular events despite effective statin-based treatment of low-density lipoprotein (LDL) cholesterol levels. The inhibition of cholesteryl ester transfer protein (CETP) by anacetrapib reduces LDL cholesterol levels and increases high-density lipoprotein (HDL) cholesterol levels. However, trials of other CETP inhibitors have shown neutral or adverse effects on cardiovascular outcomes. METHODS: We conducted a randomized, double-blind, placebo-controlled trial involving 30,449 adults with atherosclerotic vascular disease who were receiving intensive atorvastatin therapy and who had a mean LDL cholesterol level of 61 mg per deciliter (1.58 mmol per liter), a mean non-HDL cholesterol level of 92 mg per deciliter (2.38 mmol per liter), and a mean HDL cholesterol level of 40 mg per deciliter (1.03 mmol per liter). The patients were assigned to receive either 100 mg of anacetrapib once daily (15,225 patients) or matching placebo (15,224 patients). The primary outcome was the first major coronary event, a composite of coronary death, myocardial infarction, or coronary revascularization. RESULTS: During the median follow-up period of 4.1 years, the primary outcome occurred in significantly fewer patients in the anacetrapib group than in the placebo group (1640 of 15,225 patients [10.8%] vs. 1803 of 15,224 patients [11.8%]; rate ratio, 0.91; 95% confidence interval, 0.85 to 0.97; P=0.004). The relative difference in risk was similar across multiple prespecified subgroups. At the trial midpoint, the mean level of HDL cholesterol was higher by 43 mg per deciliter (1.12 mmol per liter) in the anacetrapib group than in the placebo group (a relative difference of 104%), and the mean level of non-HDL cholesterol was lower by 17 mg per deciliter (0.44 mmol per liter), a relative difference of -18%. There were no significant between-group differences in the risk of death, cancer, or other serious adverse events. CONCLUSIONS: Among patients with atherosclerotic vascular disease who were receiving intensive statin therapy, the use of anacetrapib resulted in a lower incidence of major coronary events than the use of placebo. (Funded by Merck and others; Current Controlled Trials number, ISRCTN48678192 ; ClinicalTrials.gov number, NCT01252953 ; and EudraCT number, 2010-023467-18 .)

Effects of Once-Weekly Exenatide on Cardiovascular Outcomes in Type 2 Diabetes.

Abstract BACKGROUND: The cardiovascular effects of adding once-weekly treatment with exenatide to usual care in patients with type 2 diabetes are unknown. METHODS: We randomly assigned patients with type 2 diabetes, with or without previous cardiovascular disease, to receive subcutaneous injections of extended-release exenatide at a dose of 2 mg or matching placebo once weekly. The primary composite outcome was the first occurrence of death from cardiovascular causes, nonfatal myocardial infarction, or nonfatal stroke. The coprimary hypotheses were that exenatide, administered once weekly, would be noninferior to placebo with respect to safety and superior to placebo with respect to efficacy. RESULTS: In all, 14,752 patients (of whom 10,782 [73.1%] had previous cardiovascular disease) were followed for a median of 3.2 years (interquartile range, 2.2 to 4.4). A primary composite outcome event occurred in 839 of 7356 patients (11.4%; 3.7 events per 100 person-years) in the exenatide group and in 905 of 7396 patients (12.2%; 4.0 events per 100 person-years) in the placebo group (hazard ratio, 0.91; 95% confidence interval [CI], 0.83 to 1.00), with the intention-to-treat analysis indicating that exenatide, administered once weekly, was noninferior to placebo with respect to safety (P<0.001 for noninferiority) but was not superior to placebo with respect to efficacy (P=0.06 for superiority). The rates of death from cardiovascular causes, fatal or nonfatal myocardial infarction, fatal or nonfatal stroke, hospitalization for heart failure, and hospitalization for acute coronary syndrome, and the incidence of acute pancreatitis, pancreatic cancer, medullary thyroid carcinoma, and serious adverse events did not differ significantly between the two groups. CONCLUSIONS: Among patients with type 2 diabetes with or without previous cardiovascular disease, the incidence of major adverse cardiovascular events did not differ significantly between patients who received exenatide and those who received placebo. (Funded by Amylin Pharmaceuticals; EXSCEL ClinicalTrials.gov number, NCT01144338 .)

Photocatalytic and Antimicrobial Properties of Ga Doped and Ag Doped ZnO Nanorods for Water Treatment

Water contamination is a worldwide concerning problem. Emerging contaminants have made conventional water treatment processes ineffective. This makes the search for new materials with improved physical-chemical properties for water treatment an urgent necessity. Doping metal oxides nanostructures can improve the photocatalytic degradation of contaminants and the antimicrobial activity of the material. During this process, water treatment not only involves the degradation of toxic pollutants, but also the elimination of virus and bacteria. Then, it is important to study not only the effect of a dopant in a material as photocatalyst but also the effect in its antimicrobial properties. In this work ZnO nanorods, Ga doped ZnO nanorods and Ag doped ZnO nanorods are synthesized and supported in polyethylene by a fast-hydrothermal microwave heating synthesis. Their photocatalytic performance and antimicrobial properties for water treatment were evaluated. Experiments show that Ag and Ga can improve the photocatalytic and antimicrobial properties of ZnO nanorods; the relationship between doping concentrations, with both the toxicity effect of the nanorods toward bacteria and the nanorods photocatalytic performance, is shown

Design of an electrochemical prototype to determine relative NaCl content and its application in fresh cheeses

An electrochemical prototype (ECP) was developmed and evaluated to determine NaCl electrical variables [volt (V), ampere (A), resistance (R) and power (P)] and its use in fresh cheeses. The ECP circuit consisted of two electrodes, an aluminum (anode) and a copper (cathode). The experimental parameters established in the ECP were distance between electrodes and the presence of a resistor. Seven treatment solutions were examined at 0, 2, 4, 6, 8, 10 and 12 g of NaCl/100 mL of water. Cheeses evaluated were a commercial cheese (Control) and a commercial light cheese. Treatment influenced (P<0.05) the electrical variables in NaCl solutions and cheeses. Regression analysis showed that the best fit was a quadratic model for the ECP. Prototype results showed that at higher NaCl concentrations, voltage and resistance decreased, while amperage and power increased.

Finely tunable laser based on a bulk silicon wafer for gas sensing applications

In this work a very simple continuously tunable laser based on an erbium ring cavity and a silicon wafer is presented. This laser can be tuned with very fine steps, which is a compulsory characteristic for gas sensing applications. Moreover the laser is free of mode hopping within a spectral range sufficiently wide to match one of the ro-vibrational lines of a target molecule. Here the proposed laser reached, at ∼1530 nm, a continuous tuning range of around 950 pm (>100 GHz) before mode hopping occurred, when a silicon wafer of 355 μm thickness was used. Additionally, the laser can be finely tuned with small tuning steps of <12 pm, achieving a resolution of 84.6 pm °C-1 and by using a thermo-electric cooler (TEC) the laser showed a high wavelength stability over time. These tuning characteristics are sufficient to detect molecules such as acetylene in which the mean separation between two ro-vibrational lines is around 600 pm. Finally, it is shown that the tuning range can be modified by using wafers with different thickness

Study of Thermal and Structural Properties of Starch Granules from Different Maize Genotypes

© 2014, Springer Science+Business Media New York. The thermal and structural properties of starch granules of four maize genotypes (Palomero Toluqueño native maize, HS-2 commercial hybrid, L3-Q2 M09 experimental hybrid and Cacahuacintle native maize) were studied. By using adiabatic scanning calorimetry (ASC), the specific heat capacity (cp(T)) of these samples was obtained. Also, by integration of the area under the cp(T) curves, the enthalpy for the starch gelatinization was determined, from which the percentage of gelatinized starch granules was obtained as a function of the temperature. From the X-ray diffraction patterns of the starch granules, the degree of crystallinity of the samples was derived. The average size of the starch granules, for the different maize genotypes, was calculated from the images obtained by Scanning Electron Microscopy (SEM). We found a correlation between the enthalpy of gelatinization and the average size of starch granules, and also between the degree of crystallinity and the average size of the starch granules.status: publishe

Effect of the transport vibration on the generation of the color reversion in blackberry fruit

Mexico provides 95% of the export market blackberry (Rubus fruticosus) worldwide. The characteristic black color of this fruit is an important quality factor. During its postharvest management, it can reverse its color from black to red (color reversion) this being a rejection factor in the market. Within 3-5% of the exported fruit can be rejected due to this problem. The origin of this change is not determined yet but can involve varietal aspects and postharvest handling. The objective of this study was to determine the effect of transport vibration on the color reversion. To identify the vibration conditions that generate the damage, exporting boxes with 12 clamshells of 6 oz with blackberry 'Tupy' were put under vibration patterns (5-30 Hz) with amplitude of 0.5 g. Under the identified damage conditions, different blackberry boxes were put at those conditions of vibration for 10 and 30 min, respectively, and later the fruit was stored at 3°C and 95% of HR for 2 days. The incidence of damage was evaluated and the black and red drupelets were separated from each fruit, frozen at -70°C and freeze dried for quantification of monomeric and polymeric anthocyanin. Fresh samples of each condition were prepared for its observation by optic microscopy and transmission electron microscopy (TEM). The frequency of 10 Hz and 0.5 g of amplitude generated color reversion, internal cellular damage and possible molecular changes in the anthocyanins structure. The monomeric anthocyanin content was lower on reverted drupelets (4.535 mg cyanidin-3-O-glucoside g-1 lyophilized sample) with respect to non-reverted (7.746 mg cyanidin-3-O-glucoside g-1 lyophilized sample), likewise the index of percentage of polymeric color was lower on the black drupelet (23%) in comparison with the red drupelets (37%). The tissue of the non-reverted drupelets showed a higher integrity and cellular order in comparison with the tissue of the drupelets with reversion of color. These results indicate that the frequency of 10 Hz should be avoided during the transportation of these fruits

Proapoptotic effect of endocannabinoids in prostate cancer cells

Artículo de publicación ISIIn the early stages, prostate cancer is androgendependent; therefore, medical castration has shown significant results during the initial stages of this pathology. Despite this early effect, advanced prostate cancer is resilient to such treatment. Recent evidence shows that derivatives of Cannabis sativa and its analogs may exert a protective effect against different types of oncologic pathologies. The purpose of the present study was to detect the presence of cannabinoid receptors (CB1 and CB2) on cancer cells with a prostatic origin and to evaluate the effect of the in vitro use of synthetic analogs. In order to do this, we used a commercial cell line and primary cultures derived from prostate cancer and benign prostatic hyperplasia. The presence of the CB1 and CB2 receptors was determined by immunohistochemistry where we showed a higher expression of these receptors in later stages of the disease (samples with a high Gleason score). Later, treatments were conducted using anandamide, 2-arachidonoyl glycerol and a synthetic analog of anandamide, methanandamide. Using the MTT assay, we proved that the treatments produced a cell growth inhibitory effect on all the different prostate cancer cultures. This effect was demonstrated to be dose-dependent. The use of a specific CB1 receptor blocker (SR141716) confirmed that this effect was produced primarily from the activation of the CB1 receptor. In order to understand the MTT assay results, we determined cell cycle distribution by flow cytometry, which showed no variation at the different cell cycle stages in all the cultures after treatment. Treatment with endocannabinoids resulted in an increase in the percentage of apoptotic cells as determined by Annexin V assays and caused an increase in the levels of activated caspase-3 and a reduction in the levels of Bcl-2 confirming that the reduction in cell viability noted in the MTT assay was caused by the activation of the apoptotic pathway. Finally, we observed that endocannabinoid treatment activated the Erk pathway and at the same time, produced a decrease in the activation levels of the Akt pathway. Based on these results, we suggest that endocannabinoids may be a beneficial option for the treatment of prostate cancer that has become nonresponsive to common therapies.Vicerrectoria de Investigacion y Desarrrollo of Universidad de Chile (VID) DI MULT 05/36-2 FONDECYT 1060500 1110269 1140417 Grant DI MULT 05/36-2. Grants FONDECYT, 1060500 (H.C.), 1110269 (H.C.) and 1140417 (E.C.)