1,874 research outputs found
A carbonylative cross-coupling strategy to the total synthesis of the sarcodictyins: preliminary studies and synthesis of a cyclization precursor
Improved cardiac performance with human calcitonin gene related peptide in patients with congestive heart failure
Study objective - The aim of the study was to assess the cardiovascular effects of human calcitonin gene related peptide (CGRP) in patients with congestive heart failure. Design - The effects of CGRP II (or β), 12.5 μg·h−1, given by intravenous infusion for 24 h to digitalised patients with congestive heart failure, were assessed by measurement of cardiac functional indices. Patients - Five patients (four female) were studied. Age was 73-82 years. Three were in New York Heart Association phase III and two in phase IV. Measurements and main results - The pre-ejection period to left ventricular ejection time ratio and the QT distance adjusted for heart rate were lowered by 21% and 4% respectively. The left ventricular shortening index was raised by 43%. The arterial pressure and heart rate did not change consistently. Conclusion - Calcitonin gene related peptide improves myocardial contractility in patients with congestive heart failure. This is the first time this has been show
Copper phosphoramidite-catalyzed enantioselective desymmetrization of meso-cyclic allylic bisdiethyl phosphates
A highly regio-, diastereo-, and enantioselective desymmetrization of five-, six-, and seven-membered meso-cyclic allylic bis-diethyl phosphates (2a, 2b, and 2c, respectively) was obtained with diethylzinc, using catalytic amounts of [Cu(OTf)](2).C6H6 and phosphoramidite ligands 5. Enantiomeric excesses of up to 87, 94, and >98% were obtained for the addition of diethylzinc to cyclopentene, cyclohexene, and cycloheptene bis-diethyl phosphates, respectively
Gastrointestinal helminths in calves and cows in an organic milk production system
The main aim of this study was to determine the distribution of populations of gastrointestinal helminths in lactating crossbred cows and calves during the grazing season in an organic milk production system. In addition, the potential importance of the peripartum in relation to the parasite load was examined. Between January 2007 and December 2008, parasitological fecal examinations were performed on cattle belonging to the Integrated Animal Production Program of Embrapa Agrobiology. The cows' parasite load remained low during the study period, and there were no statistical differences (p > 0.05) in comparisons between the seasons. The average egg count showed a positive correlation (0.80) with the peripartum, such that egg elimination per gram (p < 0.05) was higher during the week of labor than during the pre and postpartum periods. Calves showed low parasite loads, with significantly higher egg elimination (p < 0.05) during the winter. The study indicated that infection with gastrointestinal helminths was not a limiting factor for milk production in the organic system. Specifically, it was concluded that the nematode load can be maintained at moderate levels throughout the production system, even in the absence of anthelmintic treatment
Human perception in segmentation of sketches
In this paper, we study the segmentation of sketched engineering
drawings into a set of straight and curved segments. Our immediate objective is
to produce a benchmarking method for segmentation algorithms. The criterion
is to minimise the differences between what the algorithm detects and what
human beings perceive. We have created a set of sketched drawings and have
asked people to segment them. By analysis of the produced segmentations, we
have obtained the number and locations of the segmentation points which
people perceive. Evidence collected during our experiments supports useful
hypotheses, for example that not all kinds of segmentation points are equally
difficult to perceive. The resulting methodology can be repeated with other
drawings to obtain a set of sketches and segmentation data which could be used
as a benchmark for segmentation algorithms, to evaluate their capability to
emulate human perception of sketches
Memories in context: the social and economic function of cinema in 1950s Rome
During the 1950s, cinema in Italy blossomed, bringing film entertainment to Italians on an unprecedented scale. This study draws upon the testimony of 325 elderly Romans about their cinemagoing experiences during this period. Their memories are set in the particular context of the film programs that they (and fellow filmgoers) selected—information that is derived from daily newspapers and supplemented with trade listings of the most popular films screened in Rome. In producing a bottom-up account of cinemagoing, the paper contributes to the general debate about film culture in Italy in the postwar era
SBOL-OWL: An ontological approach for formal and semantic representation of synthetic biology information
Standard representation of data is key for the reproducibility of designs in synthetic biology. The Synthetic Biology Open Language (SBOL) has already emerged as a data standard to represent information about genetic circuits, and it is based on capturing data using graphs. The language provides the syntax using a free text document that is accessible to humans only. This paper describes SBOL-OWL, an ontology for a machine understandable definition of SBOL. This ontology acts as a semantic layer for genetic circuit designs. As a result, computational tools can understand the meaning of design entities in addition to parsing structured SBOL data. SBOL-OWL not only describes how genetic circuits can be constructed computationally, it also facilitates the use of several existing Semantic Web tools for synthetic biology. This paper demonstrates some of these features, for example, to validate designs and check for inconsistencies. Through the use of SBOL-OWL, queries can be simplified and become more intuitive. Moreover, existing reasoners can be used to infer information about genetic circuit designs that cannot be directly retrieved using existing querying mechanisms. This ontological representation of the SBOL standard provides a new perspective to the verification, representation, and querying of information about genetic circuits and is important to incorporate complex design information via the integration of biological ontologies
Transmission curves and effective refraction indices of MKO near infrared consortium filters at cryogenic temperatures
We report transmission measurements at cryogenic temperatures for 4 broad-band filters of the Mauna Kea Observatories (MKO) near-infrared filter set and 5 narrow-band filters. The spectral scans were collected using the multi-mode IR instrument of the TNG telescope (NICS) in which these filters are permanently mounted and commonly used for astronomical observations. We determined the transmission curves at a temperature of 78K and found no significant red-leak up to 2.6 microns, the data are available in electronic form on the TNG web page. We also estimated the variation of the wavelength response with the incidence angle and found it compatible with an effective refractive index of about 2
The systemic pro-inflammatory response: targeting the dangerous liaisonbetween COVID-19 and cancer
Phosphine Oxide Porous Organic Polymers Incorporating Cobalt(II) Ions: Synthesis, Characterization, and Investigation of H2Production
Suitably functionalized porous matrices represent versatile platforms to support well-dispersed catalytic centers. In the present study, porous organic polymers (POPs) containing phosphine oxide groups were fabricated to bind transition metals and to be investigated for potential electrocatalytic applications. Cross-linking of mono- and di-phosphine monomers with multiple phenyl substituents was subject to the Friedel-Crafts (F-C) reaction and the oxidation process, which generated phosphine oxide porous polymers with pore capacity up to 0.92 cm3/g and a surface area of about 990 m2/g. The formation of the R3P·BH3 borohydride adduct during synthesis allows to extend the library of phosphine-based monomeric entities when using FeCl3. The porous polymers were loaded with 0.8-4.2 w/w % of cobalt(II) and behaved as hydrogen evolution reaction (HER) catalysts with a Faradaic efficiency of up to 95% (5.81 × 10-5 mol H2 per 11.76 C) and a stable current density during repeated controlled potential experiments (CPE), even though with high overpotentials (0.53-0.68 V to reach a current density of 1 mA·cm-2). These studies open the way to the effectiveness of tailored phosphine oxide POPs produced through an inexpensive and ecofriendly iron-based catalyst and for the insertion of transition metals in a porous architecture, enabling electrochemically driven activation of small molecules
- …