Colorless devices and reception techniques for polarization multiplexed communications

Future optical networks call for flexible, high performance and low cost coherent optical receivers. We present here several advances towards such receivers, including integrated optical couplers with ultra-broad bandwidth, as well as novel reception techniques and architectures that will enable high performance coherent reception without filtering and polarization splitting elements.Universidad de Málaga - Campus de Excelencia Internacional Andalucía Tech. Spanish Ministry of Science under project TEC2013-46917-C2-1-

Grapevine leaf uptake of mineral elements influenced by sugar foam amendment of an acidic soil

The use of sugar foam (industrial waste from sugar beet extraction) as an acidic soil (raña) liming agent has been studied in a singular winegrowing region. The contents of the major elements (Al, Ca, Fe, K, Na, Mg, S, Si) and trace elements (As, Ba, Ce, Co, Cr, Cs, Cu, Ga, Hf, La, Mo, Nb, Nd, Ni, Pb, Rb, Sc, Sn, Sr, Ta, Th, U, V, W, Y, Zn, Zr) in the original soil, the amended soil and in grapevine leaves has been measured by X-ray fluorescence. The addition of sugar foam modified the agronomic properties of the original soil. The amendment caused a slight increase in major elements (Ca, 10.4 g·kg-1; Mg, 1.9 g·kg-1 and K, 12.9 g·kg-1) and decreased Al (from 62 to 57.8 g·kg-1) and Fe (from 41.2 to 26.5 g·kg-1) content. Regarding trace elements, there was an increase in levels of Ba, Rb and Sr in the amended soil in comparison to the original soil. The major elements that accumulated in the vine leaf were Ca, Mg and S (Biological Absorption Coefficient, BAC, greater than 1). As for trace elements in leaf, Ba and Sr had a "medium" BAC (0.27 and 0.8, respectively) whereas Rb had a "slight"value (0.08). It is worth noting that the bioaccumulation rate of Zn was greater than 1. The use of sugar foam as a liming agent did not have a negative effect on the absorption of major and trace elements in vine leaves and led to improved BAC values for essential elements in the grapevine. The treatment did not increase the amount of trace elements in the soil above the reference levels for the region.

Factores asociados al intento suicida e ideación suicida persistente en un Centro de Atención Primaria. Bogotá, 2004-2006

Objective: Characterising patients attempting suicide who were evaluated by psychiatry at the Primary Care Unit (PCU) 'La Estrella' from October/2004 to October/2005 and determining persistent suicidal ideation and associated factors. Methods: An initial description of attempted suicide patients (n=156). A subsequent case control study (n=77) determined persistent suicidal ideation cases (n=27). A multivariate model was used for determining the remaining factors associated with persistent suicide ideation. Results: Cases increased from 6 in October/2004 to 10 in October/2005, average 12 ± 3,6 cases monthly. 80 % were aged 30 or younger, 66,7 % were female, 24,4 % were students and 20,5 % were unemployed. 35,2 % suffered family dysfunction and 35.2% had conflicts between couples as precipitant factors. 49 % had consumed alcohol prior to the suicide attempt. Persistent suicidal ideation was associated with being 31 years old or older, being unemployed and having a higher number of previous suicide attempts, unresolved conflicts and family dysfunction. Logistical regression revealed unresolved conflicts (OR=106.7; 6,8; 1 668,4 95 % CI) and family dysfunction (OR=11.05; 1,7; 71,2 95 % CI) as predictor variables for persistent suicidal ideation. Conclusion Unresolved conflicts and family dysfunction were found to be predictor factors for persistent suicidal ideation in subjects who had attempted suicide. Consuming alcohol and other associated factors should be controlled by mental health prevention and promotion programmes

Quantum gravity, space-time structure, and cosmology

A set of diverse but mutually consistent results obtained in different settings has spawned a new view of loop quantum gravity and its physical implications, based on the interplay of operator calculations and effective theory: Quantum corrections modify, but do not destroy, space-time and the notion of covariance. Potentially observable effects much more promising than those of higher-curvature effective actions result; loop quantum gravity has turned into a falsifiable framework, with interesting ingredients for new cosmic world views. At Planckian densities, space-time disappears and is replaced by 4-dimensional space without evolution.Comment: 8 pages, 7 figures, Plenary talk at CosGrav12, held at Indian Statistical Institute, Kolkat

Maternal Hyperleptinemia Increases Arterial Stiffening and Alters Vasodilatoy Responses to Insulin in Adult Male Mice Offspring

Cardiovascular disease (CVD) is the number one cause of death in the U.S., and exposure to adverse maternal environments has been associated with the development of CVD including hypertension. Gestational diabetes mellitus (GDM) is an adverse maternal environment that has been associated with metabolic and CVD outcomes in the offspring. Key features of GDM and CVD are maternal hyperleptinemia and vascular disfunction/remodeling, respectively. Yet, there is limited information on the effects of maternal hyperleptinemia has on the function and structure of the offspring’s resistance vasculature. We hypothesize that alterations in offspring’s resistance artery structure and function underlie programming mechanisms for cardiovascular disease that are associated with maternal hyperleptinemia and GDM. To test this hypothesis, we used Leprdb/+ mice dams, which exhibit maternal hyperleptinemia and wildtype (WT) as controls. Vascular function was assessed in WT male offspring of control and hyperleptinemic dams at 31 weeks of age, after half the offspring had been fed a high fat diet (HFD) for 6 weeks. On a standard diet (SD), offspring of hyperleptinemic dams had mesenteric arteries with larger internal diameters than those of WT dams (258.36±14.99 vs 233.65±9.36 μm, p<0.05) indicative of outwardly remodeled, and enhanced maximal vasodilatory responses to insulin (39.97±6.71 vs 32.23±5.07 %, p<0.05). In offspring of WT, but not hyperleptinemic dams, HFD increased vessel wall cross-sectional area (18590.01±1251.16 vs 12807.20±1060.70 μm2, p<0.05), and enhanced the maximal vasodilatory response to acetylcholine (33.74±4.92 vs 21.86±2.73 %, p<0.05). HFD reduced the maximal response to insulin in offspring of hyperleptinemic dams compared to their WT and lean controls (21.88±3.80 vs 37.42±7.84 and 39.97±6.71 % respectively, p<0.05). Offspring of hyperleptinemic dams fed a HFD had increased elastic moduli normalized as a function of the percolation of the internal elastic lamina compared to their WT and lean controls (0.53±0.038 vs 0.34±0.023 and 0.38±0.032 ×106 dynes/cm2 respectively, p<0.05). Offspring of hyperleptinemic dams also had stiffer arteries at high pressure under both dietary conditions (2.36±0.35 vs 1.45±0.11 ×106 dynes/cm2, p<0.05). We conclude that when mice were fed a SD, maternal hyperleptinemia had beneficial effects to offspring’s vascular health, but did not protect offspring fed a HFD. Furthermore, maternal hyperleptinemia induced arterial stiffness in offspring regardless of diet. These results suggest that GDM programs offspring vascular function and structure through mechanisms that may be in part dependent on circulating maternal leptin levels and are differentially affected by postnatal developmental exposures

A comparison of cut points for measuring risk factors for adolescent substance use and antisocial behaviors in the U.S. and Colombia

As the identification and targeting of salient risk factors for adolescent substance use become more widely used globally, an essential question arises as to whether U.S.-based cut points in the distributions of these risk factors that identify high risk can be used validly in other countries as well. This study examined proportions of youth at high risk using different empirically derived cut points in the distributions of 18 measured risk factors. Data were obtained from large-scale samples of adolescents in Colombia and the United States. Results indicated that significant (p \u3c 0.05) differences in the proportions of high risk youth were found in 38.9% of risk factors for 6th graders, 61.1% for 8th graders, and 66.6% for 10th graders. Colombian-based cut points for determining the proportion of Colombian youth at high risk were preferable to U.S.-based cut points in almost all comparisons that exhibited a significant difference. Our findings suggest that observed differences were related to the type of risk factor (e.g., drug specific vs. non-drug specific). Findings from this study demonstrate the need for collecting large-scale national data on risk factors for adolescent substance use and developing country-specific cut points based on the distributions of these measures to avoid misidentification of youth at high risk

A no-singularity scenario in loop quantum gravity

Canonical methods allow the derivation of effective gravitational actions from the behavior of space-time deformations reflecting general covariance. With quantum effects, the deformations and correspondingly the effective actions change, revealing dynamical implications of quantum corrections. A new systematic way of expanding these actions is introduced showing as a first result that inverse-triad corrections of loop quantum gravity simplify the asymptotic dynamics near a spacelike collapse singularity. By generic quantum effects, the singularity is removed.Comment: 10 page