Search results for "cycle"
showing 10 items of 3119 documents
Chalcogen‐Bonding Interactions in Telluroether Heterocycles [Te(CH2)m]n (n=1-4; m=3-7)
2020
The Te…Te secondary bonding interactions (SBI) in solid heterocyclic telluroethers were explored by preparing and structurally characterizing a series of [Te(CH2)m]n (n = 1‐4; m = 3‐7) species. The SBIs in 1,7‐Te2(CH2)10, 1,8‐Te2(CH2)12, 1,5,9‐Te3(CH2)9, 1,8,15‐Te3(CH2)18, 1,7,13,19‐Te4(CH2)20, 1,8,15,22‐Te4(CH2)24, and 1,9,17,25‐Te4(CH2)28 led to the tubular packing of the molecules, as has been observed previously for related thio‐ and selenoether rings. The nature of the intermolecular interactions was explored by solid‐state PBE0‐D3/pob‐TZVP calculations involving periodic boundary conditions. The packing of molecules in 1,7,13,19‐Te4(CH2)20, 1,8,15,22‐Te4(CH2)24, and 1,9,17,25‐Te4(CH2)…
Development of sustainable ORC applications in the tertiary sector: a case study in the Mediterranean climate
2022
Abstract In recent decades, climate change strong advancement has led many countries, especially the most developed ones, to a greater sense of environmental responsibility. On a global, European and national level, adaptation/mitigation strategies and actions aimed at improving energy-environmental sustainability and resilience in the tertiary sectors have been increasingly intensified. In this sector, therefore, plays a fundamental role the integration/introduction of technologies able to operate an efficient conversion of energy, such as indeed Organic Rankine Cycle (ORC) plant, other than renewable energy sources, in order to reduce both energy consumption and pollutant emissions. Withi…
Can cycling with an E-bike improve fitness? : effect of access to an Electric Assisted Bicycle on cycling distance and cardiopulmonary fitness in ina…
2016
Masteroppgave folkehelsevitenskap - Universitetet i Agder 2016 Background: The aims of the present study were to assess the effect of an eight-month intervention with access to an Electric assisted bicycle (E-bike) on (1) the amount of E-biking, (2) changes in cardiopulmonary fitness and (3) to assess whether cycled distance was associated with changes in cardiopulmonary fitness, among inactive adults. Methods: Twenty-five inactive Norwegian adults (33 – 57 years of age, 72 % women), were recruited through convenience sampling. Participants were given an E-bike for eight (N = 23) or three (N = 2) months. Socio-demographic characteristics were reported with a questionnaire. Bicycle use was m…
Effects of marathon fatigue on running kinematics and economy
2007
International audience; The influence of marathon fatigue on both running kinematics and economy was investigated with 8 subjects. The measurements included a treadmill test at 3 steady submaximal speeds performed before and after the marathon. One complete left leg cycle was videotaped at 100 Hz from the left side at each speed. The analysis included contact time (braking and push-off') and flight time as well as displacements and angular velocities of the left hip and knee. This analysis was complemented by the measurements of the electromyographic (EMG) activity of the gastrocnemius muscle at each running velocity, and energy expenditure (E) of the last 30.s at the 2 slowest speeds. The …
Life cycle methods for environmental assessment of nanotechnology
2012
Tämä tutkielma on kirjallisuuskatsaus, joka antaa yleissilmäyksen erilaisiin elinkaarimetodeihin, joilla voidaan arvioida nanoteknologiaa sisältävien tuotteiden ympäristövaikutuksia. Työssä selvitetään elinkaariajattelun tärkeys ja kuvataan erilaisia ympäristöarviointimenetelmiä. Tässä tutkielmassa tarkastellut menetelmät ovat elinkaariarvionti (LCA), hiilijalanjälki, vesijalanjälki, ekologinen jalanjälki ja ekologinen selkäreppu (MIPS). Työ käsittelee nanoteknologiaan liittyviä ympäristöasioita ja tarkastelee elinkaarimenetelmien soveltamista ja soveltuvuutta nanoteknologiaan. Työn tuloksena raportoidaan, että kuvatut ympäristöarviointimenetelmät soveltuvat nanoteknologian vaikutusten arvi…
A role for peroxisome proliferator-activated receptor gamma in resveratrol-induced colon cancer cell apoptosis.
2014
Scope Resveratrol may function as a chemopreventive agent. A recent clinical study demonstrates a reduction in tumor cell proliferation in colorectal patients receiving repeated oral ingestion of resveratrol. However, gaps remain in our knowledge of the molecular mechanisms by which resveratrol exerts its chemopreventive effect. We have previously demonstrated that resveratrol induces apoptosis in colon cancer cells and that resveratrol can sensitize chemoresistant colon cancer cells to various drugs. Based on its ability to activate peroxisome proliferator-activated receptor gamma (PPARγ) in colon cancer cells, we sought to determine the implication of this nuclear transcription factor in …
L‐Aspartate as a high‐quality nitrogen source in Escherichia coli : Regulation of L‐aspartase by the nitrogen regulatory system and interaction of L‐…
2020
Escherichia coli uses the C4-dicarboxylate transporter DcuA for L-aspartate/fumarate antiport, which results in the exploitation of L-aspartate for fumarate respiration under anaerobic conditions and for nitrogen assimilation under aerobic and anaerobic conditions. L-Aspartate represents a high-quality nitrogen source for assimilation. Nitrogen assimilation from L-aspartate required DcuA, and aspartase AspA to release ammonia. Ammonia is able to provide by established pathways the complete set of intracellular precursors (ammonia, L-aspartate, L-glutamate, and L-glutamine) for synthesizing amino acids, nucleotides, and amino sugars. AspA was regulated by a central regulator of nitrogen meta…
De novo CCND2 mutations leading to stabilization of cyclin D2 cause megalencephaly-polymicrogyria-polydactyly-hydrocephalus syndrome
2014
Activating mutations in genes encoding phosphatidylinositol 3-kinase (PI3K)-AKT pathway components cause megalencephaly-polymicrogyria-polydactyly-hydrocephalus syndrome (MPPH, OMIM 603387)(1-3). Here we report that individuals with MPPH lacking upstream PI3K-AKT pathway mutations carry de novo mutations in CCND2 (encoding cyclin D2) that are clustered around a residue that can be phosphorylated by glycogen synthase kinase 313 (GSK-3 beta)(4). Mutant CCND2 was resistant to proteasomal degradation in vitro compared to wild-type CCND2. The PI3K-AKT pathway modulates GSK-3 beta activity(4), and cells from individuals with PIK3CA, PIK3R2 or AKT3 mutations showed similar CCND2 accumulation. CCND…
RASSF1A inhibits estrogen receptor alpha expression and estrogen-independent signalling: implications for breast cancer development
2012
The Ras association domain family 1 isoform A (RASSF1A) is a tumor suppressor whose inactivation is implicated in the development of many human cancers, including breast carcinomas. Little is known about the tumor-suppressive function of RASSF1A in breast tissue and whether its inactivation is mechanistically involved in the initiation and progression of breast tumors. Here, we show that RASSF1A inhibits breast cancer growth in vivo, and suppresses estrogen receptor (ERα) expression and function. Reconstitution of RASSF1A in MCF7 cells led to decreased ERα levels and reduced sensitivity to estrogen (E2). Concomitantly, we observed decreased expression of Id1 as well as the E2-responsive gen…
Sterigmatocystin: Occurrence, toxicity and molecular mechanisms of action – A review
2020
The mycotoxin sterigmatocystin (STE) is produced mainly by Aspergillus fungi. It has been reported to occur in grains and grain-based products, cheese, coffee, spices and beer. The STE is a known biogenic precursor of aflatoxin B1, sharing with it several structural and biological similarities. The STE has been shown to be hepatotoxic and nephrotoxic in animals and it has been classified as possible human carcinogen (group 2B) by IARC. The STE has been reported to cause a marked decrease in cell proliferation in different mammalian cells. Data available on literature suggest that the cellular mechanisms underlying STE-induced toxicity include the induction of oxidative stress, mitochondrial…