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1.
Journal of Chemical Ecology - The sex pheromone composition of alfalfa plant bugs, Adelphocoris lineolatus (Goeze), from Central Europe was investigated to test the hypothesis that insect species...  相似文献   
2.
The Council of Europe, the oldest European intergovernmental organization, recognised early on the importance of a quick and adequate response to the challenge of computer technology and the risk of its misuse. In 1989, seeking the harmonization of the law and practice in its member States and to improve international legal co‐operation, the Council of Europe adopted a recommendation and a report on computer‐related crime. These constitute, perhaps not the first, but certainly the most comprehensive, comparative analysis of the relevant substantive criminal law questions. Then followed another recommendation, in 1995, on criminal procedural law problems connected with the use of information technology. With the arrival of the cyberspace, the Council of Europe will start negotiating, in 1997, an international treaty on information technology crimes, addressing questions of criminal substantive law, procedural law and international cooperation. To safeguard the privacy of individuals and to ensure a clear regulatory environment for business in member States, the Council has also adopted a treaty on data protection, progressively supplemented with sectorial recommendations.  相似文献   
3.
Many materials become appreciably translucent in the soft X-ray range, making them suitable for use as optical elements. However, since none is Perfectly transparent, it is crucial that optimum design procedures be followed in order to minimize unnecessary optical losses. In this paper we demonstrate such a solution for the ordinary metallic zone plate and compare its performance to some recently proposed configurations which were advanced on the basis of more restricted considerations.  相似文献   
4.
The pregnancy-induced rapid degeneration of the adrenergic nerves innervating the uterus is a well-known but poorly understood phenomenon. Since most of the published investigations were carried out by histological assay, our aim was to describe the loss of the adrenergic function during pregnancy and the re-innervational procedure in the postpartum period. Myometrial and cervical samples from rats were loaded with [3H]noradrenaline and then transferred into a chamber for superfusion. After a wash-out period, fractions were collected. The fifth and fifteenth fraction tissues were stimulated with an electric field. The [3H]noradrenaline contents of the fractions were determined, together with the amount remaining in the tissue. The myometrial [3H]noradrenaline release was substantially decreased in early pregnancy, and absent in the late stage. Differences in release profile were detected between the implantation sites and the interimplantation areas. As a refinement of the results of previous histochemical studies, the noradrenergic functions of the cervix were found to be deeply affected in the early postpartum period. The pregnancy-induced denervational procedure can be followed by means of a superfusional technique after [3H]noradrenaline loading. As our technique is considered to be similar in sensitivity to histological methods, superfusion can be regarded as a model for functional investigations of pregnancy-induced denervation.  相似文献   
5.
There is growing evidence regarding the role of mitochondrial dysfunction in osteoarthritis (OA) and rheumatoid arthritis (RA). However, quantitative comparison of synovial mitochondrial derangements in these main arthritis forms is missing. A prospective clinical study was conducted on adult patients undergoing knee surgery. Patients were allocated into RA and OA groups based on disease-specific clinical scores, while patients without arthritis served as controls. Synovial samples were subjected to high-resolution respirometry to analyze mitochondrial functions. From the total of 814 patients, 109 cases were enrolled into the study (24 RA, 47 OA, and 38 control patients) between 1 September 2019 and 31 December 2021. The decrease in complex I-linked respiration and dyscoupling of mitochondria were characteristics of RA patients, while both arthritis groups displayed reduced OxPhos activity compared to the control group. However, no significant difference was found in complex II-related activity between the OA and RA groups. The cytochrome C release and H2O2 formation were increased in both arthritis groups. Mitochondrial dysfunction was present in both arthritis groups; however, to a different extent. Consequently, mitochondrial protective agents may have major benefits for arthritis patients. Based on our current study, we recommend focusing on respiratory complex I in rheumatoid arthritis research.  相似文献   
6.
The mechanism that leads to microbial inactivation by high hydrostatic pressure remains elusive. In this study, a high-pressure system interfaced with a photomultiplier tube (PMT) was developed to monitor cellular metabolism in situ using bioluminescent bacterial strains. Preliminary characterization of the system was performed using Pseudomonas fluorescens 5RL expressing lux proteins from Vibrio fischeri. Stepwise increases in pressure at 34 MPa and above resulted in decreased bioluminescence. Square wave exposure to pressures of 69, 103 and 138 MPa showed bioluminescence reductions greater than 95%, but when cells were returned to ambient pressure bioluminescence returned to 51, 38, and 4% of initial bioluminescence values, respectively. An Escherichia coli strain expressing lux proteins from V. fischeri was constructed to determine whether this reversible effect could be observed in another bacterial genus. Square wave perturbations of 69, 103 and 138 MPa resulted in bioluminescence reductions of about 94% at the highest pressure treatment. Upon decompression, bioluminescence returned to 74, 58 and 30% of the initial bioluminescence values for cells treated at 69, 103 and 138 MPa, respectively. These results suggest that square wave exposure to pressure up to 138 MPa induces reversible cell damage in P. fluorescens 5RL and E. coli VF lux.  相似文献   
7.
Csonka S  Weymann I  Zarand G 《Nanoscale》2012,4(12):3635-3639
We present a proposal for a fully electrically controllable quantum dot based spin current injector. The device consists of a quantum dot that is strongly coupled to a ferromagnetic electrode on one side and weakly coupled to a nonmagnetic electrode on the other side. The presence of the ferromagnetic electrode results in an exchange field that splits the dot level. We show that this exchange-induced splitting can lead to almost full spin polarization of the current flowing through the device. Moreover, we also demonstrate that the sign of polarization can be changed by the gate or the bias voltage within a switching time in the nanosecond range. Thus, the proposed device can operate as an electrically controlled, rapidly switchable spin current source, which can be realized in various state-of-the-art nanostructures.  相似文献   
8.
9.
Four devices are discussed. In each of these, electromagnetic waves of wavelength λ (which may be in the optical range) are to be used to modulate the energy of extreme relativistic charged particle beams on a scale of ≳λ/2. The devices are: (1) two-wave modulators; the well-known optical klystron is a special case and has been used in the past for energy modulation. The other three are proposed as appropriate alternatives, depending on the circumstances: (2) vacuum modulator; it is the simplest in construction, and its energy modulation amplitude is essentially the function of only the power carried by the wave (e.g., laser power) and not the geometry nor λ; (3) Cherenkov modulator; and (4) resonator energy modulator. Their capabilities, including the energy modulation amplitude, and efficiency, are compared  相似文献   
10.
There is a growing body of evidence showing the importance of physical activity against acute ischemic events in various organs. Ischemia/reperfusion injury (I/R) is characterized by tissue damage as a result of restriction and subsequent restoration of blood supply to an organ. Oxidative stress due to increased reactive oxygen species formation and/or insufficient antioxidant defense is considered to play an important role in I/R. Physical activity not only decreases the general risk factors for ischemia but also confers direct anti-ischemic protection via myokine production. Myokines are skeletal muscle-derived cytokines, representing multifunctional communication channels between the contracting skeletal muscle and other organs through an endocrine manner. In this review, we discuss the most prominent members of the myokines (i.e., brain-derived neurotrophic factor (BDNF), cathepsin B, decorin, fibroblast growth factors-2 and -21, follistatin, follistatin-like, insulin-like growth factor-1; interleukin-6, interleukin-7, interleukin-15, irisin, leukemia inhibitory factor, meteorin-like, myonectin, musclin, myostatin, and osteoglycin) with a particular interest in their potential influence on reactive oxygen and nitrogen species formation or antioxidant capacity. A better understanding of the mechanism of action of myokines and particularly their participation in the regulation of oxidative stress may widen their possible therapeutic use and, thereby, may support the fight against I/R.  相似文献   
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