Search results for "AMS"

Multipolar interactions in the D pocket of thrombin: large differences between tricyclic imide and lactam inhibitors.

2006

Two series of tricyclic inhibitors of the serine protease thrombin, imides (+/-)-1-(+/-)-8 and lactams (+/-)-9-(+/-)-13, were analysed to evaluate contributions of orthogonal multipolar interactions with the backbone C=O moiety of Asn98 to the free enthalpy of protein-ligand complexation. The lactam derivatives are much more potent and more selective inhibitors (K(i) values between 0.065 and 0.005 microM, selectivity for thrombin over trypsin between 361- and 1609-fold) than the imide compounds (Ki values between 0.057 and 23.7 microM, selectivity for thrombin over trypsin between 3- and 67-fold). The increase in potency and selectivity is explained by the favorable occupancy of the P-pocke…

Forest drainage: a threat to benthic biodiversity of boreal headwater streams?

1998

1. Forest drainage, including mainly ditching of waterlogged peatlands in order to increase wood growth, has caused substantial changes in the hydrology and water quality of Finnish streams. However, knowledge on the ecological impact of these changes is poor. This paper studies the potential impact of forest drainage, catchment characteristics and habitat factors on the water quality and benthic macroinvertebrates in headwater streams of the River Isojoki, western Finland. An intensive programme of water sampling was carried out at nine study sites, while zoobenthic samples covered a total of 18 streams. 2. According to multivariate regression models concentrations of aluminium and suspend…

Changes in habitat structure, benthic invertebrate diversity, trout populations and ecosystem processes in restored forest streams: a boreal perspect…

2007

SUMMARY 1. Most Finnish streams were channelised during the 19th and 20th century to facilitate timber floating. By the late 1970s, extensive programmes were initiated to restore these degraded streams. The responses of fish populations to restoration have been little studied, however, and monitoring of other stream biota has been negligible. In this paper, we review results from a set of studies on the effects of stream restoration on habitat structure, brown trout populations, benthic macroinvertebrates and leaf retention. 2. In general, restoration greatly increased stream bed heterogeneity. The cover of mosses in channelised streams was close to that of unmodified reference sites, but a…

Stress transfer mechanism investigation in hybrid steel trussed-concrete beams by push-out tests

2014

Abstract Results of push-out tests carried out on Hybrid Steel Trussed–Concrete Beams (HSTCBs) before and after the concrete casting are presented and interpreted. Firstly, in order to check the ability of weldings before casting, tensile tests were performed on specimens reproducing different types of welded joints. Simplified design formulae were used to predict their ultimate strength. Secondly, results obtained by push-out tests on specimen representative of the beam before and after the concrete casting are presented and discussed. Finally, simplified analytical models proposed by the current European building code were adapted to the specific typology to roughly predict the ultimate s…

FEM analysis of push-out test response of Hybrid Steel Trussed Concrete Beams (HSTCBs)

2015

Abstract Aiming to investigate the steel truss–concrete stress transfer mechanism in Hybrid Steel Trussed–Concrete Beams (HSTCBs), a three-dimensional (3D) nonlinear Finite Element (FE) model is developed. The constitutive relationship of the steel composing the plates and the rebars is modeled by means of a quadri-linear law, while the concrete behavior is defined by means of a Concrete Damaged Plasticity (CDP) model, suitable for modeling concrete and brittle materials. Two main failure mechanisms are considered, namely the tensile cracking and the compressive crushing. In order to accurately grasp the complicate dowel and bond phenomena arising at the steel–concrete interface, a 3D solid…

Etudes culturelles en Italie: un paradigme possible

2010

Risk Factors and treatment needs of batterer intervention program participants with substance abuse problems

2021

espanolEl objetivo de este estudio fue identificar los principales factores de riesgo y necesidades de tratamiento de los participantes en un programa de intervencion con maltratadores (BIP) con problemas de abuso de alcohol y/o drogas (ADAP), mas alla de sus problemas de abuso de substancias, teniendo en cuenta cuatro conjuntos de variables: sociodemograficas (i.e., edad, nivel educativo, ingresos, empleo y estatus de inmigrante), trastornos de personalidad y ajuste psicologico (i.e., sintomatologia clinica, trastornos de personalidad, ira, impulsividad y autoestima), variables socio-relacionales (i.e., apoyo comunitario, apoyo intimo, eventos vitales estresantes y rechazo social percibido…

Space partitioning of exchange-correlation functionals with the projector augmented-wave method

2018

We implement a Becke fuzzy cells type space partitioning scheme for the purposes of exchange-correlation within the GPAW projector augmented-wave method based density functional theory code. Space partitioning is needed in the situation where one needs to treat different parts of a combined system with different exchange-correlation functionals. For example, bulk and surface regions of a system could be treated with functionals that are specifically designed to capture the distinct physics of those regions. Here, we use the space partitioning scheme to implement the quasi-nonuniform exchange-correlation scheme, which is a useful practical approach for calculating metallic alloys on the gene…

Process and technology challenges in swift-starting virtual teams

2007

Originally published in the journal Information & Management : http://www.sciencedirect.com/science/journal/03787206 Virtual teams often face tight schedules and a need to start quickly and perform instantly. The goal of our study was to enhance understanding of the challenges faced by such teams. We used time–interaction–performance theory as the framework for following the processes and functions within virtual teams working on a systems development task. Our study provided a detailed examination of the group process, applied to virtual teams working under time pressure. The challenges faced by virtual teams in such settings showed that teams must work to enhance their effectiveness in mu…

Day-night differences in the sensitivity of adrenoceptors in the Syrian hamster pineal gland: an in vivo iontophoretic study.

1989

Abstract Investigations on the regulation of pineal melatonin synthesis in the Syrian hamster revealed distinct differences compared to this well-understood mechanism in rat. E.g., a circadian profile of pineal norepinephrine (NE) is absent, there is no β-adrenoceptor sensitivity during daytime and adrenergic receptor supersensitivity is not easily achieved. To elucidate the action of NE on pineal receptor sites, the effects of iontophoretic application of adrenergic compounds on spontaneous electrical discharge rates of pinealocytes were investigated during day- and nighttime. Following application of either NE, isoproterenol or clonidine, cells were activated, inhibited or not affected. W…