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81.
The International Journal of Life Cycle Assessment - Vegetative roofs (VRs) are fully planted roof spaces that offer aesthetic view, storm water management, sound insulation, energy savings, and...  相似文献   
82.

Pathogens carried by ticks pose a threat to both human and animal health across the world. Typically associated with rural landscapes, ticks appear to adapt well to life in urban recreational areas. Although Dermacentor reticulatus is commonly found across Europe, data on the prevalence of pathogens in this tick species, in an urban environment, are very limited. PCR was used to examine 368 D. reticulatus individuals collected in the Zwierzyniecki Forest Nature Reserve in Bia?ystok, Poland. In total, 10.3% of ticks were infected, with Babesia spp. (9.2%), Anaplasma phagocytophilum (0.8%) and Borrelia burgdorferi sensu lato (0.3%). Rickettsia spp., Bartonella spp., and Coxiella burnetii were not detected. Sequence analysis for Babesia-positive samples identified 79.4% of them as Babesia canis, 8.8% as Babesia microti, 5.9% as Babesia spp., 2.9% as Babesia venatorum, and 2.9% as Babesia vogeli. Results obtained in this study indicate that D. reticulatus ticks found within the urban premises of the study area are infected with at least three pathogens and therefore are an important factor in public health risk for tick-borne diseases.

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83.
Neurochemical Research - Acrylamide (ACR) is an environmental pollutant with well-demonstrated neurotoxic and neurodegenerative effects in both humans and experimental animals. The present study...  相似文献   
84.
85.
Rhizoliths, that is, roots fossilized by secondary carbonates, have been known for ages and are increasingly used for paleoenvironmental reconstructions. However, knowledge about their formation mechanisms remains limited. This study reports the mineralogical and chemical characterization of rhizoliths at different stages of mineralization and fossilization in the Late Pleistocene loess–paleosol sequence of Nussloch (SW Germany). Scanning electron microscopy coupled with elemental mapping and 13C solid‐state nuclear magnetic resonance were used to concomitantly characterize the mineral and organic matter of the rhizoliths. These joint analyses showed for the first time that large rhizoliths are not necessarily remains of single large roots but consist of numerous microrhizoliths as remains of fine roots, formed mainly by calcium carbonates with only low amounts of Mg and Si. They further revealed that the precipitation of secondary carbonates occurs not only around, but also within the plant root and that fossilization leads to the selective preservation of recalcitrant root biopolymers—lignin and suberin. The precipitation of secondary carbonates was observed to occur first around fine roots, the epidermis acting as a first barrier, and then within the root, within the cortex cells, and even sometimes around the phloem and within the xylem. This study suggests that the calcification of plant roots starts during the lifetime of the plant and continues after its death. This has to be systematically investigated to understand the stratigraphic context before using (micro)rhizoliths for paleoenvironmental reconstructions in terrestrial sediments.  相似文献   
86.
BackgroundTreatment of ST-elevation myocardial infarction (STEMI) has improved over the years. Current challenges in the management of STEMI are achievement of early reperfusion and the prevention of microvascular injury. Sonothrombolysis has emerged as a potential treatment for acute myocardial infarction, both for epicardial recanalisation as well as improving microvascular perfusion. This study aims to determine safety and feasibility of sonothrombolysis application in STEMI patients in the ambulance.MethodsTen patients with STEMI will be included and treated with sonothrombolysis in the ambulance during transfer to the PCI centre. Safety will be assessed by the occurrence of ventricular arrhythmias and shock during sonothrombolysis intervention. Feasibility will be assessed by the extent of protocol completion and myocardial visibility. Efficacy will be determined by angiographic patency rate, ST-elevation resolution, infarct size and left ventricular volumes, and function measured with cardiovascular magnetic resonance imaging, and contrast and strain echocardiography. A comparison will be made with matched controls using an existing STEMI database.DiscussionSonothrombolysis is a novel technique for the treatment of cardiovascular thromboembolic disease. The first clinical trials on its use for STEMI have demonstrated promising results. This study will be the first to examine the feasibility of in-ambulance sonothrombolysis for STEMI.Trial registrationEU Clinical Trials Register (identifier: 2019-001883-31), registered 2020-02-25.  相似文献   
87.
This study examined the reliability and scaling of the flexor carpi radialis (FCR) V-wave during submaximal and maximal voluntary muscle contractions (MVC). 23 participants were tested on three separate sessions. For each session, participants performed isometric wrist flexions at five contraction levels (20, 40, 60, 80 and 100 %MVC). When the target contraction level was reached, a supramaximal electrical stimulus was applied to the median nerve in order to elicit an FCR V-wave. Across all participants, the FCR V-wave amplitude, normalized to its superimposed M-wave amplitude, increased from 0.030 ± 0.001 to 0.143 ± 0.015 (P < 0.001) as the muscle contraction increased from 20 to 100 %MVC. Contraction level did not influence the reliability of evoking the FCR V-wave, as the V-wave demonstrated both stability and consistency. With the exception of a single day main effect during the 20 %MVC condition, V:Msup was not different across days or trials (P > 0.05) indicating measurement stability. High reliability co-efficients (0.827–0.913) at each contraction level signified measurement consistency. This study establishes that FCR V-waves can be reliably evoked during both submaximal and maximal muscle contractions and suggests the possibility for FCR V-wave recordings to be used to document neuromuscular adaptations associated with factors such as training or fatigue.  相似文献   
88.
Five novel macrocyclic monoterpene O-glycosides, parkinsenes A–E (15), and eleven known phenolic metabolites including three 3-O-glycosylflavonols (68), five C-glycosylflavones (913), p-hydroxybenzoic acid (14), esculetin (15), and diosmetin (16) were isolated from the leaves and small twigs of Parkinsonia aculeata L. (Fabaceae). Their structures were established by chemical and spectroscopic analyses (UV, ESI–MS, and 1D/2D NMR). The investigated 80 % aqueous methanol extract (AME) showed significant analgesic, antipyretic, anti-inflammatory, hepatoprotective, hypoglycemic, hypocholesterolemic, and antioxidant activities in a dose-dependent manner using two different doses 250 and 500 mg/kg b. wt.  相似文献   
89.
The aim of the present work is to evaluate the effect of caffeine, the world’s most popular psychoactive drug, on the electric activity of the rat’s brain that exposed to extremely low-frequency magnetic field (ELF-MF), during 15 days. The obtained results showed that administration of caffeine in a group of rats by dose of 10 mg/kg (equivalent to human daily consumption) caused a reduction in the mean power amplitude of electroencephalogram (EEG) trace for almost all frequency bands especially α (8–12 Hz). It was observed that the influence of caffeine was more evident in motor cortex than in visual cortex. While the exposure of another group to ELF-MF of intensity 0.2 mT during the same period caused an enhancement in the mean power amplitude of most EEG frequency bands; this was more observed in the right hemisphere of the brain than that of the left hemisphere. The administration of caffeine while rats were exposed to ELF-MF, led, after 5 days of exposure, to a great increase in the mean power amplitude of α band at all places of recording electrodes. It may be concluded that caffeine administration was more effective in reducing the hazardous of ELF-MF in motor cortex than in visual cortex.  相似文献   
90.
Nα‐Boc‐Nim‐(4‐toluenesulfonyl‐l ‐histidylbenzotriazole) enables convenient acylation of N‐, O‐, S‐, and C‐nucleophiles with no detectable racemization. We report efficient syntheses of novel histidine‐containing di‐, tri‐, and tetra‐peptides and models for the preparation of potentially biologically active histidine N‐, O‐, S‐, and C‐conjugates. Copyright © 2013 European Peptide Society and John Wiley & Sons, Ltd.  相似文献   
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