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A review of the literature on the impact of sexual contacts between adults and boys reveals the existence of two principal outcomes: 1) some participants develop various disorders once in adulthood, such as behavioural problems, sexual disorders, or personality problems; 2) some participants do not present with any major disorders in the long run. These different outcomes may be associated with several moderating variables related to the sexual contacts, such as the level of coercion at the time of these contacts, the bond between the child and the adult, or the context of the sexual relation. However, the conclusions relating to the relations between early sexual contacts with adults and subsequent problems of adaptation in adulthood are difficult to determine. This is because of various methodological problems associated with relevant studies (i.e., definition of these contacts, nature of the sample, method evaluation, statistical analyses). In this article, we propose certain avenues of research that may help clarify this problem. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Hurst P.J. Lewis S.H. Keane J.P. Aram F. Dyer K.C. 《IEEE transactions on circuits and systems. I, Regular papers》2004,51(2):275-285
Several Miller compensation schemes using a current buffer in series with the compensation capacitor to modify the right-half-plane zero in fully differential two-stage CMOS operational amplifiers are analyzed. One scheme uses a current mirror as a current buffer, while the rest use a common-gate transistor as a current buffer. The gain transfer functions are derived for each topology, and approximate transfer-function coefficients are found that allow accurate estimation of the zero(s) and poles. 相似文献
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Jan Haas Karen S. Frese Farbod Sedaghat-Hamedani Elham Kayvanpour Rewati Tappu Rouven Nietsch Oguz Firat Tugrul Michael Wisdom Carsten Dietrich Ali Amr Tanja Weis Torsten Niederdrnk Michael P. Murphy Thomas Krieg Marcus Drr Uwe Vlker Jens Fielitz Norbert Frey Stephan B. Felix Andreas Keller Hugo A. Katus Benjamin Meder 《International journal of molecular sciences》2021,22(4)
With more than 25 million people affected, heart failure (HF) is a global threat. As energy production pathways are known to play a pivotal role in HF, we sought here to identify key metabolic changes in ischemic- and non-ischemic HF by using a multi-OMICS approach. Serum metabolites and mRNAseq and epigenetic DNA methylation profiles were analyzed from blood and left ventricular heart biopsy specimens of the same individuals. In total we collected serum from n = 82 patients with Dilated Cardiomyopathy (DCM) and n = 51 controls in the screening stage. We identified several metabolites involved in glycolysis and citric acid cycle to be elevated up to 5.7-fold in DCM (p = 1.7 × 10−6). Interestingly, cardiac mRNA and epigenetic changes of genes encoding rate-limiting enzymes of these pathways could also be found and validated in our second stage of metabolite assessment in n = 52 DCM, n = 39 ischemic HF and n = 57 controls. In conclusion, we identified a new set of metabolomic biomarkers for HF. We were able to identify underlying biological cascades that potentially represent suitable intervention targets. 相似文献
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In this study, we analyze data from surveys conducted in 2006 and 2010, tracking changes in awareness, engagement and attitudes surrounding emerging digital cultural forms over this 5‐year period. Our analysis, based on results from thousands of adults around the globe, shows that not only have remixes, mashups and other forms of “configurable culture” become mainstream phenomena, but also that the attitudes surrounding their cultural legitimacy are shifting. While copyright industries still promote a binary theft/permission framework, many people acknowledge the validity of some appropriation, and are actively negotiating the law's limitations. Yet, those most engaged in challenging dominant copyright narratives and exploring these emergent forms are those who hold the reins of cultural power: the young, educated and wealthy. 相似文献
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Mechanical properties of wood plastic composites (WPCs) manufactured from sawdust and virgin and/or recycled plastics, namely high density polyethylene (HDPE) and polypropylene (PP), were studied. Sawdust was prepared from beech industrial sawdust by screening to the desired particle size and was mixed with different virgin or recycled plastics at 50% by weight fiber loading. The mixed materials were then compression molded into panels. Flexural and tensile properties and impact strength of the manufactured WPCs were determined according to the relevant standard specifications. Although composites containing PP (virgin and recycled) exhibited higher stiffness and strength than those made from HDPE (virgin and recycled), they had lower unnotched impact strengths. Mechanical properties of specimens containing recycled plastics (HDPE and PP) were statistically similar and comparable to those of composites made from virgin plastics. This was considered as a possibility to expand the use of recycled plastics in the manufacture of WPCs. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 3641–3645, 2006 相似文献
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Hossein Derakhshankhah Rana Jahanban-Esfahlan Somayeh Vandghanooni Sattar Akbari-Nakhjavani Bakhshali Massoumi Babak Haghshenas Aram Rezaei Amir Farnudiyan-Habibi Hadi Samadian Mehdi Jaymand 《应用聚合物科学杂志》2021,138(24):50578
Gelatin (Gel)-based pH- and thermal-responsive magnetic hydrogels (MH-1 and MH-2) were designed and developed as novel drug delivery systems (DDSs) for cancer chemo/hyperthermia therapy. For this goal, Gel was functionalized with methacrylic anhydride (GelMA), and then copolymerized with (2-dimethylaminoethyl) methacrylate (DMAEMA) monomer in the presence of methacrylate-end capped magnetic nanoparticles (MNPs) as well as triethylene glycol dimethacrylate (TEGDMA; as crosslinker). Afterward, a thiol-end capped poly(N-isopropylacrylamide) (PNIPAAm-SH) was synthesized through an atom transfer radical polymerization technique, and then attached onto the hydrogel through “thiol-ene” click grafting. The preliminary performances of developed MHs for chemo/hyperthermia therapy of human breast cancer was investigated through the loading of doxorubicin hydrochloride (Dox) as an anticancer agent followed by cytotoxicity measurement of drug-loaded DDSs using MTT assay by both chemo- and chemo/hyperthermia-therapies. Owing to porous morphologies of the fabricated magnetic hydrogels according to scanning electron microscopy images and strong physicochemical interactions (e.g., hydrogen bonding) the drug loading capacities of the MH-1 and MH-2 were obtained as 72 ± 1.4 and 77 ± 1.8, respectively. The DDSs exhibited acceptable pH- and thermal-triggered drug release behaviors. The MTT assay results revealed that the combination of hyperthermia therapy and chemotherapy has synergic effect on the anticancer activities of the developed DDSs. 相似文献
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Traditionally, two alternative design approaches have been available to engineers: top-down and bottom-up. In the top-down
approach, the design process starts with specifying the global system state and assuming that each component has global knowledge
of the system, as in a centralized approach. The solution is then decentralized by replacing global knowledge with communication.
In the bottom-up approach, on the other hand, the design starts with specifying requirements and capabilities of individual
components, and the global behavior is said to emerge out of interactions among constituent components and between components
and the environment. In this paper we present a comparative study of both approaches with particular emphasis on applications
to multi-agent system engineering and robotics. We outline the generic characteristics of both approaches from the MAS perspective,
and identify three elements that we believe should serve as criteria for how and when to apply either of the approaches. We
demonstrate our analysis on a specific example of load balancing problem in robotics. We also show that under certain assumptions
on the communication and the external environment, both bottom-up and top-down methodologies produce very similar solutions.
相似文献
Valentino CrespiEmail: |
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In this paper, we review the state-of-the-art in surface-enhanced Raman scattering (SERS) based optical detection techniques
with an application focus on cancer diagnostics. As we describe herein, SERS has several analytical, biological and engineering
advantages over other methods including extremely high sensitivity, inherent molecular specificity of unlabeled targets, and
narrow spectral bands. We review advances in both in vitro and in vivo applications of SERS and examine how technical issues
with the technology are being addressed. A special technology focus is given to emerging optofluidic devices which aim to
merge microfluidic and optical detection technologies into simple packages. We conclude with a brief discussion of some of
the emerging challenges in the field and some of the approaches that are likely to enhance their application.
Y. S. Huh and A. J. Chung contributed equally. 相似文献