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31.
全新安全战略--自防御网络   总被引:1,自引:0,他引:1  
不久前,计算机病毒还只是一种令人不快的小问题,很少引起高层管理人员的关注。但是现在,指数级增长的安全威胁、协作式应用和互联环境让网络安全问题成为了报纸的头条新闻。这里只举一个例子:在2003年1月,SQL Slammer蠕虫导致全球各地的大量网络陷于瘫痪,甚至让韩国电信的Freet  相似文献   
32.
A hydrophilic surface suitable for solid‐state peptide synthesis was developed on a solid support called a lantern. The split‐and‐mix combinatorial technique was used to prepare about 500 surfaces in a very short time. Surfaces were analyzed according to values for gel formation, percentage weight grafted, grafted copolymer composition, and number of functional groups per lantern. These values were correlated to the purity of a peptide synthesized on these surfaces. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 3371–3378, 2003  相似文献   
33.
Sapphire suffers a dramatic loss of c-axis compression strength at elevated temperatures. Irradiation of sapphire with fission-spectrum neutrons to an exposure of ∼1022 neutrons/m2 in the core of a 1 MW fission reactor increased the c-axis compression strength by a factor of ∼3 at 600 °C. Strength was similarly improved when 99% of slow neutrons (?0.1 eV) were removed by 10B and Cd shields during irradiation. Annealing at 600 °C for 10 min changed the yellow-brown color of irradiated sapphire to pale yellow, but had no effect on compressive strength. Annealing irradiated sapphire at 1200 °C for 24 h reduced the compressive strength to its baseline value. Transmission electron microscopy suggests that fast-neutron-induced displacement damage inhibits the propagation of r-plane twins which are responsible for the low compressive strength. When irradiated with 10B and Cd shielding, sapphire that was not grown in iridium crucibles is safe for unrestricted handling after 1 month.  相似文献   
34.
This study is designed to compare and test some predictions about the self-evaluation process based on the theories of Festinger and Rotter. Contrary to suggestions by Rotter, it was found that minimal goals were no more resistant to change than were expected scores. Changes in minimal goals and expected scores tended to occur so as to minimize discrepancies with actual performance, and thus reduce dissonance in accordance with Festinger's theory. Consistent with Festinger's theory of social comparison processes, it was found that individual's self-evaluations are only influenced by reference group norms in the absence of a more objective criterion for self-evaluation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
35.
While heterologous germ cell transplantation was successful in pigs and goats, autologous transplantation alone has been reported to result in donor-derived spermatogenesis in cattle. The objective of this study was to investigate whether the transplantation of heterologous germ cells could result in colonization of recipient testes in cattle of different breeds. Testicular cells were isolated from 8 Bos taurus donor bull calves and then transferred into 15 Bos indicus-cross bull calves. All animals were prepubertal, donors were aged 5-7 months and recipients 5-11 months, and scrotal circumferences ranged from 15 to 22 cm. Single cell suspensions of donor testicular cells, prepared by enzymatic digestion, were labelled with fluorescent dyes PKH26 or CFDA-SE, before transfer into the rete testis of recipients under ultrasonographic guidance. To assess the longevity of colonization by donor cells, recipients were castrated 2-30 weeks after cell transfer. Donor cells were observed in 15/25 (60%) of the testes that received PKH26-labelled cells, whereas no CFDA-SE-positive cell was identified in any recipients. The maturity of the donors or recipients (measured by scrotal circumference) did not affect colonization potential. In freshly isolated tubules, clumps of PKH26-positive cells were observed, which indicated either cell division or extensive local colonization of specific areas of the tubules. In frozen sections, PKH26-positive cells were identified on the seminiferous tubule basement membrane, which indicated that these cells had successfully migrated from the tubule lumen and were likely to be spermatogonia. We conclude that PKH26 was more suitable for labelling donor testis cells and donor cells can be identified up to 6 months following transfer. These results indicate that allogeneic transplantation of testicular cells can occur between Bos taurus and Bos indicus cattle. Further studies will investigate functionality of transferred testicular cells.  相似文献   
36.
Objective: To evaluate the contribution of injection anxiety to disease modifying therapy (DMT) adherence among individuals with multiple sclerosis (MS). Injection anxiety has been associated with medication discontinuation early in the course of treatment, but little is known about the relationship between injection anxiety and sustained DMT adherence over time. Method: Eighty-nine outpatients receiving care at a Veterans Administration MS clinic completed a telephone survey at baseline and monthly telephone follow-up for 6 months. Results: Participants were established DMT users (M = 3.43 years, SD = 3.29), with relatively high adherence overall (over 80% achieved 80% adherence or greater). Using logistic regression and controlling for demographics, MS disability, type of DMT, and time on DMT, the authors found that baseline injection anxiety predicted lower levels of adherence at 4 months and 6 months, with a similar trend at 2 months. Conclusion: Sustained adherence to DMT remains a challenge for a subset of individuals with MS well beyond the initial period of acclimation. Injection anxiety is an important and promising target of psychological intervention during all periods of medication use. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
37.
This paper briefly reviews research that describes the sensation, generation and consumer acceptance of beef flavor. Humans sense the five basic tastes in their taste buds, and receptors in the nasal and sinus cavities sense aromas. Additionally, trigeminal senses such as metallic and astringent are sensed in the oral and nasal cavities and can have an effect on the flavor of beef. Flavors are generated from a complex interaction of tastes, tactile senses and aromas taken collectively throughout the tongue, nasal, sinus and oral cavities. Cooking beef generates compounds that contribute to these senses and result in beef flavor, and the factors that are involved in the cookery process determine the amount and type of these compounds and therefore the flavor generated. A low‐heat, slow cooking method generates primarily lipid degradation products, while high‐heat, fast cookery generates more Maillard reaction products. The science of consumer acceptance, cluster analyses and drawing relationships among all flavor determinants is a relatively new discipline in beef flavor. Consumers rate beef that has lipid degradation products generated from a low degree of doneness and Maillard flavor products from fast, hot cookery the highest in overall liking, and current research has shown that strong relationships exist between beef flavor and consumer acceptability, even more so than juiciness or tenderness. © 2015 Society of Chemical Industry  相似文献   
38.
Objective: To describe depressive symptoms, posttraumatic stress disorder (PTSD), and posttraumatic growth at 6 and 12 months following amputation and to explore differences by demographic variables and cognitive processing of trauma. Participants: 83 adults with newly acquired limb loss. Setting: Two large metropolitan hospitals. Main Outcome Measures: The Patient Health Questionnaire depression module, PTSD Checklist, and Posttraumatic Growth Inventory. Results: Significant depressive and PTSD symptoms were reported by 15%-25% of participants. Relatively low levels of posttraumatic growth were reported. Negative cognitive processing predicted depressive and PTSD symptoms at 6 months. Positive cognitive processing predicted posttraumatic growth at 12 months. Conclusion: Cognitive processing appears to be integral to positive and negative psychosocial outcomes following amputation and should be targeted by clinical interventions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
39.
Assessed the comparative effectiveness of heart rate biofeedback (HRB) training, false HRB training, and systematic desensitization (SD) in reducing speech anxiety for 27 students chosen for their high scores on the item "speaking before a group" of the Fear Survey Schedule. Results indicate that all 3 groups demonstrated a decrease in self-reported (Personal Report of Confidence as a Speaker) and overt motor components of anxiety during 2 posttreatment assessment periods. Physiological measures (HR and skin conductance), however, indicate that the HRB group was associated with less physiological responding during the posttreatment assessments of anxiety relative to the other 2 groups. Results demonstrate that the 3 behavioral component measures of anxiety are not always highly correlated. (4 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
40.
Sequence analysis of the newly defined SSU81 gene revealed an adjacent open reading frame (ORF) encoding a protein whose deduced amino acid sequence is identical to that of ribosomal protein L17. The DNA sequence of this region is different from that of the RPL17A gene and therefore represents a duplicate gene encoding L17. We have designated this gene RPL17B. The RPL17B coding region is split by an intron that occurs in the same position (codons 14/15) as the intron in RPL17A. The RPL17B promoter region includes two TATA boxes, a canonical UASRPG motif, and several pyrimidine-rich tracts. RPL17B was mapped by CHEF and lambda clone grid hybridization blots to the right arm of chromosome V, linked to the TRP2 and RAD51 genes. A partial ORF was identified adjacent to RPL17B and SSU81 that is homologous to an ORF (designated A509) physically linked to RPL17A. This observation, and the identical position of the introns within the RPL17 genes, suggest that one RPL17 locus arose by duplication and translocation of the other. The complete 3·8 kbp DNA sequence encompassing RPL17B has been entered in the GenBank data library under Accession Number U15653.  相似文献   
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