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921.
Andrej Kitanovski 《Liver Transplantation》2020,10(10)
The need for energy‐efficient and environmentally friendly refrigeration, heat pumping, air conditioning, and thermal energy harvesting systems is currently more urgent than ever. Magnetocaloric energy conversion is among the best available alternatives for achieving these technological goals and has been the subject of substantial basic and applied research over the last two decades. The subject is strongly interdisciplinary, requiring proper understanding and efficient integration of knowledge in different specialized fields. This review article presents a historical and up‐to‐date account of the energy‐related applications of magnetocaloric materials and information about their processing and magnetic fields, thermodynamics, heat transfer, and other relevant characteristics. The article also discusses the conceptual design of magnetocaloric refrigeration and power generation systems and some guidelines for future research in the field. 相似文献
922.
As common ragweed (Ambrosia
artemisiifolia L.) spreads across Europe and other regions, it is becoming both a health and an economic threat. To better understand which
environmental conditions facilitate the spread of the invasive species, in 2010, a greenhouse experiment was conducted determining
the effects of various nitrogen levels (10, 50 and 100 kg N/ha), soil moisture level (low and high) and competition levels
(no competition, medium competition and high competition) on the growth parameters of ragweed. Single-grown ragweed responded
favourably to the medium nitrogen and water increase, whereas the ragweed growth parameters in competition stands increased
only when high levels of nitrogen and water were added. High competition reduced the total dry matter of ragweed by up to
83%, but the ragweed continued to increase its relative growth rate during the full-flowering stage and allocate its dry matter
to reproductive parts, producing up to 70 seeds per plant. Ragweed is a poor competitor when there is high resource availability;
however, under disturbance and in the shortage of nutrients and water conditions, the intensity of competition decreases and
the ragweed performance is minimally affected. The addition of medium levels of nitrogen to promote the growth of competitive
species, prevention of disturbance and establishment of plant communities with stress-tolerant species is measures that should
help to prevent the further spread of ragweed. 相似文献
923.
The preparation of MCPA had no formative effect on the shoot apex although it affected the development of lateral buds formed at the sides. As soon as the compound ceased to act the development of the spike continued normally. The formative effect of MCPA is displayed in the structure of the ear by a partial or complete reduction of its internodes. The inhibitory action of the preparation is sometimes reflected in a blockade of the formation of lateral shoots in a part of one or both orthostichs, or else the lateral bud is initiated but does not continue to develop and thus a branchless node is produced. Occasionally, on the contrary, the preparation has a stimulating effect; segments of the lateral stem of the first order are elongated and develop similarly to the main stem which brings about the so-called “branching” of the spike frequently imitating dichotomy. Rich branching occurs on stimulating several lateral stems. A frequently met morphosis is a locally disturbed distichy, and a decussation of orthostichs or their rotating by an angle of less than 90° and a disturbance in the normal course of mesotonic branching. The formation of apparent or true flower whorls formed in consequence to a reduction of the ear internodes or a disturbance of distichy is usually connected with the reduction of individual inflorescence parts, with an increase in the number of inflorescence parts, with their partial or complete cohesion and with a change of their position. 相似文献
924.
ObjectiveWe aimed to assess treatment outcomes and disease control status in patients with acromegaly using patient- and clinician-reported outcome tools and to analyze correlations among different components of both tools.MethodsThis cross-sectional study included 72 patients from a national referral center with a median follow-up of 8 (5-12) years. The baseline SAGIT score at diagnosis was determined retrospectively, whereas the follow-up SAGIT and acromegaly quality of life questionnaire (AcroQoL) results were assessed at the most recent visit and by additional telephone interviews.ResultsAll SAGIT subscores decreased significantly from baseline to follow-up (global score from 14 to 4 [P < .001]). The SAGIT scores at baseline did not discriminate the current disease control status. However, a higher baseline SAGIT score and subscore T were associated with uncontrolled disease after the first-line treatment. Diagnostic delay was correlated with baseline S, A, G, and global SAGIT scores. At the follow-up, the global SAGIT score discriminated between cured/controlled and uncontrolled groups (4 vs 6 [P = .007]). The AcroQoL score was 69.3, with the personal relations subscale being the least affected and the physical scale being the most affected. There was no difference in the AcroQoL score between patients classified as uncontrolled or cured/controlled. At baseline and follow-up, there were significant negative correlations between S and A subscores and AcroQoL score. A higher body mass index, the presence of swelling, joint symptoms, headaches, sleep apnea, and hypertension significantly impaired quality of life.ConclusionOur results emphasize the complementary nature of the patient- and clinician-reported outcome tools in acromegaly management. We identified modifiable signs, symptoms, and comorbidities as treatment targets that might help clinicians improve quality of life in this population. 相似文献
925.
Jurassic neptunian dikes are common within Upper Triassic to Lower Jurassic platform limestone of the Julian Alps. At Mt Mangart,
the following geometries were observed: irregular dissolution cavities, thin penetrative fractures, larger fractures with
sharp sidewalls, and laterally confined breccia bodies. Inside a complex neptunian dike system two main generations of infillings
were differentiated. The first generation is heterogeneous and consists of bioclastic limestones, representing uniquely preserved
sediments subdivided into five different microfacies. The second generation is more common and typically consists of coarse-grained
breccias with host-rock clasts and marly limestone matrix containing echinoderms. Fracture formation and void filling of the
first generation of neptunian dikes is dated as Pliensbachian and is interpreted to be caused by the Julian carbonate platform
dissection due to widely recognized Lower Jurassic Tethyan rifting. The timing of formation for the second generation is only
broadly constrained, ranging from the Pliensbachian to the Late Cretaceous. 相似文献
926.
927.
Aleš Snoj Andrej Razpet Tea Tomljanović Tomislav Treer Simona Sušnik 《Conservation Genetics》2007,8(5):1213-1217
Genetic founder effects of a historical translocation (1965; app. 12 generations ago) of endangered softmouth trout from the
only remaining indigenous population to an adjacent uninhabited river were investigated.
A comparison of 15 microsatellites from contemporary samples in both the source and re-established populations indicated a
very low level of genetic diversity within the two populations. Furthermore, considerable differences in estimates of variability
and effective population sizes were detected between populations, but no recent bottlenecks were evident. Our data suggest
that the re-established population has lost variation due to genetic drift associated with founder effects following the translocation.
Accordingly, in relation to management, we suggest that the re-established population could serve as a secondary source of
individuals to buffer possible extinction due to demographic events. Finally, conservation initiatives to enhance the census
population size and increase levels of variability in the re-established population are proposed.
Electronic Supplementary Material
Supplementary material is available in the online version of this article at and is accessible for authorized users. 相似文献
928.
Our results show that cytokines derived from macrophages play an important role in pathogenesis of arthritis triggered by
CpG oligodinucleotide (CpG ODN). IL-12 is in this respect an important immunomodulator during the development of joint inflammation. 相似文献
929.
Ziegelhöffer Attila Ravingerová Tatiana Džurba Andrej Tribulová Narcisa Slezák Jan Breier Albert Szekeres László 《Molecular and cellular biochemistry》1996,160(1):257-263
It is demonstrated a fast and significant depression in the sarcolemmal (Na,K)-ATPase activity that occurs as early as 25 sec after the onset of Ca2+ depletion, and participates in the development of Ca2+-paradox in the rat heart. Pretreatment of the animals with 7-oxo-prostacyclin (PG12) 24–48 h prior to the experiment prevented fairly the Ca2+-depletion-induced depression in (Na,K)ATPase activity and the accompanying structural and functional damage to the heart and sarcolemma during Ca2+-depletion as well as the development of Ca2+-paradox during the subsequent Ca2+-repletion. Pretreatment with PGI, was chosen intentionally because previous experiments revealed, that in its late effect the drug is acting via stabilizing the membranes due induction of high activity of (Na,K)-ATPase that has increased affinity to ATP. From results obtained the following may be concluded: If during the phase of Ca2+-deprivation, the capability of heart sarcolemma to maintain sodium extrusion remains preserved, the expected aggravation of Ca2+-overload injury to Ca2+-paradox that would develop during Ca2+-repletion, may be definitely prevented. Sufficiently preserved (Na,K)-ATPase activity, hand in hand with stabilized sarcolemmal structure, may prevent an accumulation of sodium beneath the sarcolemma and consequently also an overexcessive entry of Ca2+ into the myocytes. 相似文献
930.
We evaluate 3D models of human nucleoside diphosphate kinase, mouse cellular retinoic acid binding protein I, and human eosinophil neurotoxin that were calculated by MODELLER , a program for comparative protein modeling by satisfaction of spatial restraints. The models have good stereochemistry and are at least as similar to the crystallographic structures as the closest template structures. The largest errors occur in the regions that were not aligned correctly or where the template structures are not similar to the correct structure. These regions correspond predominantly to exposed loops, insertions of any length, and non-conserved side chains. When a template structure with more than 40% sequence identity to the target protein is available, the model is likely to have about 90% of the mainchain atoms modeled with an rms deviation from the X-ray structure of ≈ 1 Å, in large part because the templates are likely to be that similar to the X-ray structure of the target. This rms deviation is comparable to the overall differences between refined NMR and X-ray crystallography structures of the same protein. © 1995 Wiley-Liss, Inc. 相似文献