Concerns about breast cancer and relations to psychosocial well-being in a multiethnic sample of early-stage patients.

Much work on psychosocial sequelae of breast cancer has been guided by the assumption that body image and partner reaction issues are focal. In a tri-ethnic sample of 223 women treated for early-stage breast cancer within the prior year, the authors assessed a wider range of concerns and relations to well-being. Strongest concerns were recurrence, pain, death, harm from adjuvant treatment, and bills. Body-image concerns were moderate; concern about rejection was minimal. Younger women had stronger sexual and partner-related concerns than older women. Hispanic women had many stronger concerns and more disruption than other women. Life and pain concerns and sexuality concerns contributed uniquely to predicting emotional and psychosexual disruption; life and pain concerns and rejection concerns contributed to predicting social disruption. In sum, adaptation to breast cancer is a process bearing on several aspects of the patient's life space. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Children Who Question Their Heterosexuality.

Many gay, lesbian, and bisexual adults report a period of childhood sexual questioning--an uneasy questioning of their heterosexuality brought on by same-sex attractions and motivating same-sex sexual exploration. This article evaluates hypotheses about the correlates, causes, and consequences of childhood sexual questioning. Participants were 182 children in the 4th through 8th grades. Compared with children more confident in their heterosexuality, sexual-questioning children reported more impaired self-concepts, fewer same-sex-typed attributes (but not more cross-sex-typed attributes), a greater sense of feeling different from same-sex others, and lesser satisfaction with their gender assignment. Short-term longitudinal analyses indicated that sexual questioning is more likely a determinant than a consequence of these correlated variables. However, influences of sexual questioning on these outcomes were small. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Hyperbranched polyhedral oligomeric silsesquioxane (HB‐POSS) nanomaterials for high transmission and radiation‐resistant space and solar applications

Hyperbranched polycarbosiloxanes and polysiloxanes with octafunctional polyhedral oligomeric silsesquioxane (POSS) branchpoints and curable alkoxysilane or silanol end‐groups were formulated with linear polysiloxanes to fabricate transparent and robust nanostructured POSS‐containing materials for use in a range of high performance space and solar applications. The effect of methyl vs. phenyl content, architecture and linear polysiloxane mass on transmission, thermal, physical, and proton, electron and UV radiation resistance properties was determined, and the physical properties of the nanomaterials were tailored to produce adhesives, or rigid or flexible coatings as desired. The methyl formulations showed superior electron resistance relative to a commercial space control material and to a POSS‐free HB polymer control material, even when directly exposed to radiation in coating form, whereas the phenyl formulations were shown to have inferior electron and UV resistance. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 3849–3861, 2013     

Long-Ultraviolet-Excited White-Light Emission in Rare-Earth-Activated Yttrium-Oxyorthosilicate

White-light emission was achieved by activating yttrium oxyorthosilicate with two rare-earth elements, (Y_{1− m − n} Ce _m Tb _n )₂SiO₅. Ce³⁺ strongly absorbs at λ _ex =358 nm and produces a broad, mainly blue emission with a tail that extends out to 600 nm (orange), and transfers energy efficiently to Tb³⁺, which produces strong green-line emissions at 550 nm and some red emission around 650 nm. At λ_{e x} =358 nm, chromaticity coordinates of the optimally activated (Y_0.9625Ce_0.0075Tb_0.03)₂SiO₅ were found to be x =0.266, y =0.365 with a color temperature 8512 K. Upon mixing in another red-emitting phosphor, (Y_0.955Bi_0.005Eu_0.04)₂O₃, the chromaticity and color rendering index values were improved.     

An exploratory study of social support, distress, and life disruption among low-income hispanic women under treatment for early stage breast cancer.

Relationships between distress and perceived availability of social support were examined in 51 Hispanic women being treated for early stage breast cancer. Distress and different types (emotional, instrumental) and sources (spouse, women family members, other family members, friends) of support were measured at presurgery, postsurgery, and at 3-, 6-, and 12-month follow-ups. Emotional support from friends and instrumental support from spouse at presurgery predicted lower distress postsurgery. No other prospective benefits of perceived support emerged. Distress at several time points predicted erosion of subsequent support, particularly instrumental support from women in the family. In contrast to the adverse effects of distress (and independent of them), illness-related disruption of recreational and social activities at 6 months elicited greater support at 12 months. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Human immunodeficiency virus type 1 membrane fusion mediated by a laboratory-adapted strain and a primary isolate analyzed by resonance energy transfer

Previous studies of human immunodeficiency virus type 1 (HIV-1) envelope glycoprotein-mediated membrane fusion have focused on laboratory-adapted T-lymphotropic strains of the virus. The goal of this study was to characterize membrane fusion mediated by a primary HIV-1 isolate in comparison with a laboratory-adapted strain. To this end, a new fusion assay was developed on the basis of the principle of resonance energy transfer, using HeLa cells stably transfected with gp120/gp41 from the T-lymphotropic isolate HIV-1LA1 or the macrophage-tropic primary isolate HIV-1JR-FL. These cells fused with CD4+ target cell lines with a tropism mirroring that of infection by the two viruses. Of particular note, HeLa cells expressing HIV-1JR-FL gp120/gp41 fused only with PM1 cells, a clonal derivative of HUT 78, and not with other T-cell or macrophage cell lines. These results demonstrate that the envelope glycoproteins of these strains play a major role in mediating viral tropism. Despite significant differences exhibited by HIV-1JR-FL and HIV-1LAI in terms of tropism and sensitivity to neutralization by CD4-based proteins, the present study found that membrane fusion mediated by the envelope glycoproteins of these viruses had remarkably similar properties. In particular, the degree and kinetics of membrane fusion were similar, fusion occurred at neutral pH and was dependent on the presence of divalent cations. Inhibition of HIV-1JR-FL envelope glycoprotein-mediated membrane fusion by soluble CD4 and CD4-IgG2 occurred at concentrations similar to those required to neutralize this virus. Interestingly, higher concentrations of these agents were required to inhibit HIV-1LAI envelope glycoprotein-mediated membrane fusion, in contrast to the greater sensitivity of HIV-1LAI virions to neutralization by soluble CD4 and CD4-IgG2. This finding suggests that the mechanisms of fusion inhibition and neutralization of HIV-1 are distinct.     

Building a virtual community for a tele-learning environment

This article presents the results of a research project that requires students and faculty to evolve a virtual community in a university class. The concepts, requirements, and importance of a virtual community are discussed, along with the skill requirements necessary for students to participate effectively in a virtual community. The Web sites and class assignments that form the basis of a virtual community are described. Finally, the importance of enriching the learning experience and humanizing the learning process through the use of a virtual community is also discussed     

Tin oxide-black molybdenum photothermal solar energy converters

Efficient photothermal solar converters exhibit high solar absorptance and low thermal emittance. The spectral selectivity of both tin oxide (SnO₂) and black molybdenum (BlMo) has been demonstrated in the literature. Tin oxide is transparent in the visible yet becomes reflective in the infrared. Black molybdenum is absorptive in the visible while exhibiting only moderate infrared reflectance, if post-deposition annealing is avoided. Coating BlMo with SnO₂ increases absorptance due to antireflection in the visible and decreases emittance due to the higher infrared reflectance of SnO₂. Typical $\text{SnO}{}_2\text{BlMo}$ stacks exhibit an absorptance of 91 % (of the air mass 2 solar input) and a normal emittance of 13 % (of the 200 C blackbody curve). Both layers are produced under one atmosphere at temperatures as high as 500 C. Exposure of the stacks to air at 400 C for over 48 hours has resulted in no observable optical changes.     

混频器用作开关，可使DAC采样频率加倍

只要把两个DAC交错接入一个单元,你就可以有效地使一个DAC的采样速率增加一倍.轮流更新每个DAC,并切换到合适的输出端,就可以使整个系统的有效吞吐率加倍.在复用这些DAC的输出时使用高质量的高速开关,这对系统总体性能是至关重要的.