Gluon mass and freezing of the QCD coupling

Infrared finite solutions for the gluon propagator of pure QCD are obtained from the gauge-invariant non-linear Schwinger-Dyson equation formulated in the Feynman gauge of the background field method. These solutions may be fitted using a massive propagator, with the special characteristic that the effective mass employed drops asymptotically as the inverse square of the momentum transfer, in agreement with general operator-product expansion arguments. Due to the presence of the dynamical gluon mass the strong effective charge extracted from these solutions freezes at a finite value, giving rise to an infrared fixed point for QCD.Comment: 3 pages, 2 figures, based on talk given at the 2007 Europhysics Conference on High Energy Physics, Manchester, 19-25 Jul

Influences of salinity on the physiology and distribution of the Arctic coralline algae, Lithothamnion glaciale (Corallinales, Rhodophyta)

In Greenland, free-living red coralline algae contribute to and dominate marine habitats along the coastline. Lithothamnion glaciale dominates coralline algae beds in many regions of the Arctic, but never in Godthåbsfjord, Greenland, where Clathromorphum sp. is dominant. To investigate environmental impacts on coralline algae distribution, calcification and primary productivity were measured in situ during summers of 2015 and 2016, and annual patterns of productivity in L. glaciale were monitored in laboratory-based mesocosm experiments where temperature and salinity were manipulated to mimic high glacial melt. The results of field and cold-room measurements indicate that both L. glaciale and Clathromorphum sp. had low calcification and photosynthetic rates during the Greenland summer (2015 and 2016), with maximum of 1.225 ± 0.17 or 0.002 ± 0.023 μmol CaCO3 · g-1 · h-1 and -0.007 ±0.003 or -0.004 ± 0.001 mg O2 · L-1 · h-1 in each species respectively. Mesocosm experiments indicate L. glaciale is a seasonal responder; photosynthetic and calcification rates increase with annual light cycles. Furthermore, metabolic processes in L. glaciale were negatively influenced by low salinity; positive growth rates only occurred in marine treatments where individuals accumulated an average of 1.85 ± 1.73 mg · d-1 of biomass through summer. These results indicate high freshwater input to the Godthåbsfjord region may drive the low abundance of L. glaciale, and could decrease species distribution as climate change increases freshwater input to the Arctic marine system via enhanced ice sheet runoff and glacier calving.Peer reviewedFinal Accepted Versio

The juice of fresh leaves of Catharanthus roseus Linn. reduces blood glucose in normal and alloxan diabetic rabbits

BACKGROUND: The leaf juice or water decoction of Catharanthus roseus L. (Apocyanaceae) is used as a folk medicine for the treatment of diabetes all over the world. In the present investigation, the leaf juice of C. roseus has been evaluated for its hypoglycemic activity in normal and alloxan-induced diabetic rabbits. METHODS: The blood glucose lowering activity of the leaf juice was studied in normal and alloxan-induced (100 mg/kg, i.v.) diabetic rabbits, after oral administration at doses of 0.5, 0.75 and 1.0 ml/kg body weight. Blood samples were collected from the marginal ear vein before and also at 4, 6, 8, 10, 12, 16, 18, 20 & 24 h after drug administration and blood glucose was analyzed by Nelson-Somogyi's method using a visible spectrophotometer. The data was compared statistically by using Student's t-test. RESULTS: The leaf juice of C. roseus produced dose-dependent reduction in blood glucose of both normal and diabetic rabbits and comparable with that of the standard drug, glibenclamide. The results indicate a prolonged action in reduction of blood glucose by C. roseus and the mode of action of the active compound(s) of C. roseus is probably mediated through enhance secretion of insulin from the β-cells of Langerhans or through extrapancreatic mechanism. CONCLUSIONS: The present study clearly indicated a significant antidiabetic activity with the leaf juice of Catharanthus roseus and supports the traditional usage of the fresh leaves by Ayurvedic physicians for the control of diabetes

Evaluating Alternative Nutrient Sources in Subsistence-Level Aquaponic Systems

Many food production methods are both economically and environmentally unsustainable. Our project investigated aquaponics, an alternative method of agriculture that could address these issues. Aquaponics combines fish and plant crop production in a symbiotic, closed-loop system. We aimed to reduce the initial and operating costs of current aquaponic systems by utilizing alternative feeds. These improvements may allow for sustainable implementation of the system in rural or developing regions. We conducted a multi-phase process to determine the most affordable and effective feed alternatives for use in an aquaponic system. At the end of two preliminary phases, soybean meal was identified as the most effective potential feed supplement. In our final phase, we constructed and tested six full-scale aquaponic systems of our own design. Data showed that soybean meal can be used to reduce operating costs and reliance on fishmeal. However, a more targeted investigation is needed to identify the optimal formulation of alternative feed blends

Política de desarrollo fronterizo y gobernanza local en América del Sur

18 páginasThis paper studies the dynamics of horizontal and vertical coordination arising from a set of sectoral and intersectoral projects in the border areas of Colombia–Venezuela and Brazil–Argentina. These are characterized by some common features such as population density, conurbation and trade patterns that in the absence of border regulation policies strengthen border security and development guidelines and extend local leadership. Officials and directors named in local governance networks were surveyed and interviewed at the municipal level. This research concludes that patterns of feedback between the local and the national are fundamental to the success of limited and informal initiatives, but strategic in cross-border cooperation and interaction.Este artículo estudia la dinámica de coordinación horizontal y vertical que surge de un conjunto de proyectos sectoriales e intersectoriales en las zonas fronterizas de Colombia-Venezuela y Brasil-Argentina. Estos se caracterizan por algunas características comunes, como la densidad de población, la conurbación y los patrones comerciales que, en ausencia de políticas de regulación fronteriza, fortalecen la seguridad fronteriza y las pautas de desarrollo y amplían el liderazgo local. Se encuestó y entrevistó a funcionarios y directores nombrados en redes de gobernanza local a nivel municipal. Esta investigación concluye que los patrones de retroalimentación entre lo local y lo nacional son fundamentales para el éxito de iniciativas limitadas e informales, pero estratégicas en la cooperación e interacción transfronteriza

Subarachnoid hemorrhage caused by intracranial aneurysms, experience in 82 patients Tratamiento de la hemorragia subaracnoidea aneurismática en el Hospital Clínico de la Universidad de Chile

© 2014, Sociedad Medica de Santiago. All rights reserved. Background: One third of patients with subarachnoid hemorrhage caused by intracranial aneurysms, die. Aim: Review of medical records of patients with subarachnoid hemorrhage treated at a clinical hospital. Material and Methods: Review of medical records of patients discharged from the hospital between 2006 and 2011 with the diagnosis of subarachnoid hemorrhage. Patients initially or subsequently treated elsewhere were not analyzed. Results: The medical records of 82 patients aged 24 to 100 years (77% females), were analyzed. The clinical diagnosis at the onset of the condition was correct in 82% of cases. In 95% of patients, an angiographic study and subsequent surgical intervention of the aneurysm were carried out within 24 hours of diagnosis. Global mortality was 23%. Twelve patients died prior to any possible treatment, due to the severity of the disease. Seventy six aneurysms in 70 patients were treated with clips or coils

Estimation of Apigenin, an Anxiolytic Constituent, in Turnera aphrodisiaca

An HPTLC densitometric method has been developed to estimate apigenin in Turnera aphrodisiaca aerial and its segregated parts (leaves, stems, flowers and fruits) so that plant can be standardized on the basis of its bioactive marker. The apigenin content in methanol extract of T. aphrodisiaca aerial parts was found to be about fourteen times less than acid hydrolyzed methanol extract of the plant indicating the presence of most of apigenin in glycosidic form. Amongst different plant parts, flowers possessed maximum content of apigenin followed by leaves. The apigenin content was also determined in three marketed formulations of T. aphrodisiaca viz., NLK, DWSG and SBL. DWSG contained higher content of apigenin. Aerial parts of the plant were collected at bimonthly intervals over a period of one year in the months of January, March, May, July, September and November. The plant material collected in September showed maximum content of apigenin