Surface Collective Modes in the Topological Insulators Bi_{2}Se_{3} and Bi_{0.5}Sb_{1.5}Te_{3-x}Se_{x}.

We used low-energy, momentum-resolved inelastic electron scattering to study surface collective modes of the three-dimensional topological insulators Bi_{2}Se_{3} and Bi_{0.5}Sb_{1.5}Te_{3-x}Se_{x}. Our goal was to identify the "spin plasmon" predicted by Raghu and co-workers [Phys. Rev. Lett. 104, 116401 (2010)]. Instead, we found that the primary collective mode is a surface plasmon arising from the bulk, free carriers in these materials. This excitation dominates the spectral weight in the bosonic function of the surface χ^{"}(q,ω) at THz energy scales, and is the most likely origin of a quasiparticle dispersion kink observed in previous photoemission experiments. Our study suggests that the spin plasmon may mix with this other surface mode, calling for a more nuanced understanding of optical experiments in which the spin plasmon is reported to play a role.

Post-transplant HLA class II antibodies and high soluble CD30 levels are independently associated with poor kidney graft survival.

HLA-specific antibodies (HSA) and soluble CD30 (sCD30) were measured in 208 renal transplant recipients with functioning grafts at least 1 year after transplantation (median 8.2 years) to investigate the predictive value of HSA and sCD30 on subsequent graft outcome. HSA (class I and class II) were detected by both ELISA LAT-M and Luminex LabScreen assays. Data on graft outcome was collected with a median follow-up time of 3.5 years after antibody and sCD30 measurement. Recipients with post-transplant HLA class II antibodies had particularly poor graft outcome with a hazard ratio (HR) of 7.8 (p < 0.0001) when detected by ELISA, and a HR of 6.0 (p < 0.0001) when detected by Luminex. A high post-transplant sCD30 level >or=100 U/mL was associated with increased risk of subsequent graft failure (HR 2.7, p = 0.03). sCD30 and HSA had an independent and additive association with graft outcome. Recipients with HLA class II antibody and high sCD30 had the highest risk of subsequent graft failure (HR 43.4, p < 0.0001 and HR 18.1, p = 0.0008 for ELISA and Luminex, respectively). These data show that detection of HSA and serum sCD30 measured at least 1-year post-transplant provides valuable and predictive information regarding subsequent graft outcome.

Mental health service use by African American women: exploration of subpopulation differences.

Studies focusing on mental health service use have consistently viewed African American women as a homogeneous population, and very few studies have examined subgroup differences. However, important differences exist both within and between groups in lifestyle, stressors, type and availability of support resources, societal interactions, and risk-taking behaviors. This study examined rates and patterns of mental health service use by African American lesbian women and a matched sample of heterosexual women. Results suggest both similarities and differences in factors associated with use of services. Despite evidence of substantial emotional distress, relatively few African American lesbian and heterosexual women reported current use of mental health services. These findings are consistent with past reports on African American heterosexual women but differ from other published reports on lesbians' use of therapy. Findings from this study, including clear differences between lesbians and heterosexual women in past use of therapy and preferences for mental health providers, have important implications for service provision.

Sexual assault and alcohol abuse: a comparison of lesbians and heterosexual women.

PURPOSE: To compare and contrast lesbians' and heterosexual women's experiences of sexual assault and to investigate relationships between sexual assault and alcohol abuse. METHODS: In-depth interviews were conducted with 63 lesbians and a demographically matched comparison group of 57 heterosexual women. Lesbians' and heterosexual women's experiences of sexual assault, drinking levels, and alcohol-abuse indicators were compared using descriptive statistics. LISREL analysis was used to test the effects of sexual assault on a latent measure of alcohol abuse. RESULTS: Lesbians reported more childhood sexual experiences, were more likely to meet the study definition for childhood sexual abuse (CSA), and were more likely to perceive themselves as having been sexually abused as children. CSA was associated with lifetime alcohol abuse in both lesbian and heterosexual women. However, adult sexual assault (ASA) was associated with alcohol abuse only in heterosexual women. IMPLICATIONS: Sexual assault is a common experience among both lesbians and heterosexual women. Findings emphasize the importance of asking about sexual assault in health histories, and assessing clients for substance abuse and other sequelae of sexual assault.

Sexual identity and alcohol-related outcomes: contributions of workplace harassment.

PURPOSE: While workplace sexual harassment has received a great deal of attention in both the popular media and scientific literature, less attention has been directed to the differential occurrence of sexual harassment among lesbians, gay men, and heterosexual men and women, and the relationships between these experiences and alcohol-related outcomes. Additionally, the distribution of alcohol-related outcomes of non-sexual forms of workplace harassment among these groups have not been adequately explored. METHOD: Using data from a university-based study of workplace harassment and alcohol use (N = 2492), we focus on exposure to workplace harassment and alcohol-related outcomes for lesbians, gay men, and bisexuals compared to heterosexual men and women. RESULTS: Lesbian/bisexual women did not differ significantly from heterosexual women in their experiences of workplace harassment. However, stronger linkages between harassment and increased alcohol consumption and problems were found for lesbian and bisexual women than for heterosexual women. Gay/bisexual men, on the other hand, experienced significantly more sexual harassment than heterosexual men, but did not report a corresponding increase in alcohol use and abuse. IMPLICATIONS: Implications for future research on sexual identity, alcohol use, and workplace harassment are discussed.

Implementation of an interdisciplinary Behavior Management Program.

OBJECTIVE: To describe the establishment and utilization of an interdisciplinary Behavior Management Program in a Transitional Care Unit as a new model of Geriatrics Practice. DESIGN: Descriptive Study. SETTING: A 50-bed Transitional Care Unit in a Veterans Affairs Medical Center in Syracuse, New York. PARTICIPANTS: All residents admitted to the Transitional Care Unit were observed for a 6-month period under the Behavior Management Program. PROGRAM STRUCTURE: The Behavior Management Program involved an interdisciplinary team approach to the management of behavioral disturbances. This included development of a Behavior Team and a comprehensive Behavior Observation Record, which readily assisted caregivers in determining and monitoring target behaviors that required modification. Both nonpharmacological and pharmacological interventions were employed to assist in the modification of behavioral disturbances. RESULTS: The Behavior Management Program enhanced the overall care of Transitional Care Unit residents with behavioral disturbances. The more appropriate use of medications for specific target behaviors led to a reduction in behavioral disturbance episodes and increased the earlier diagnosis and treatment of depression. The interdisciplinary nature of the Behavior Management Program promoted educational efforts and camaraderie among staff and created a stronger liaison between the Transitional Care Unit and the Psychiatry Service. In addition, several management improvements were identified as a result of the implementation of the Behavior Management Program. CONCLUSIONS: An interdisciplinary Behavior Management Program can prove to be a valuable asset in the management of behaviors for people with dementia, psychiatric illness, and other medical illnesses. More effective use of nonpharmacological and psychopharmacological interventions enhances the quality of life in a frail older population. This approach has strong potential for successful use in a variety of clinical settings by providers and caregivers alike.

Effective peer responses to impaired nursing practice.

Chemical dependency within the nursing profession continues to be a significant problem affecting health care delivery. This article presents up-to-date information on responding to a peer who is demonstrating impaired nursing practice. Specific information on the scope and impact of the problem, indicators of impairment, return to practice, and fitness to practice issues are addressed. In addition, the authors share their insight regarding progress, trends, and challenges in responding to impaired practice.

Toward an understanding of addiction.

Given the large number of women with drug use and addiction problems, nurses have frequent opportunities to intervene to promote positive changes in drug use behavior. Classifications of drugs commonly used and terms relevant to drug use are presented. A discussion of different perspectives on addiction and a theory of change for addictive behaviors provides a foundation for working with women who have addictions.

Kinetic analysis of human deoxycytidine kinase with the true phosphate donor uridine triphosphate.

Deoxycytidine kinase is the rate-limiting process in the activation for several clinically important antitumor agents. Previous studies have focused on deoxycytidine (dCyd) and adenosine triphosphate (ATP) as substrates for this enzyme. In view of recent data indicating that uridine triphosphate (UTP) is the physiologic phosphate donor for this enzyme, a study of the kinetic properties of dCyd kinase with dCyd and UTP was undertaken. The results presented here demonstrate that UTP and ATP produce kinetically distinguishable differences in nucleoside phosphorylation by dCyd kinase. At high dCyd concentrations, dCyd kinase exhibited substrate activation with ATP. In contrast, in the presence of UTP, substrate inhibition was observed at concentrations of dCyd greater than 3 microM. Inhibition by dCyd was noncompetitive with respect to UTP and could not be reversed by a 200-fold increase in UTP concentration, indicating that the inhibition was not due to dCyd binding at the nucleotide binding site. The kinetic mechanism for dCyd kinase was determined with dCyd and UTP as substrates. UTP was the preferred phosphate donor with a true Km value of 1 microM compared to 54 microM with ATP, resulting in a 50-fold greater substrate efficiency for UTP. Although the double-reciprocal plots with UTP produced parallel lines, initial velocity plots with other phosphate donors and product inhibition studies indicated that dCyd kinase formed a ternary complex with its substrates. The parallel lines with UTP were apparently due to a low dissociation constant for UTP, which was calculated as more than 13-fold lower than its Km value. Analysis of product inhibition studies indicated that dCyd kinase followed an ordered A-B random P-Q reaction sequence, with UTP as the first substrate to bind. In contrast, previous results demonstrated a random bi-bi sequence for dCyd kinase in the presence of ATP. The combined results indicate that the enzyme can follow a random bi-bi reaction sequence, but with UTP as the phosphate donor, the addition of nucleotide prior to dCyd is strongly preferred. The noncompetitive substrate inhibition, which was independent of UTP concentration, indicates that high concentrations of dCyd promote addition of the nucleoside prior to UTP, resulting in a lower velocity.

Gender differences in alcohol and other drug use among young adults.

This article describes gender differences in alcohol and other drug (AOD) use and misuse in a representative sample of young women and men in the United States. Data were drawn from the National Longitudinal Survey of Youth (NLSY) and focus on gender differences in prevalence and patterns of AOD use in African American, Hispanic, and White young adults ages 19 to 24 years old. Findings are summarized and implications for prevention are presented.

Use of alcohol among lesbians: research and clinical implications.

A review of the literature on the prevalence of alcohol use and problems among lesbians reveals that the few studies yielding information on this population are beset by design and methodological problems. Those factors possibly associated with higher risk status of lesbians are identified, as are gaps in the literature, and implications for clinical practice and research are discussed.

Improving nurses' responses toward substance-misusing patients: a clinical evaluation project.

Practitioners in acute and primary care settings often fail to identify and intervene with chemically dependent patients. Counterproductive attitudes, lack of knowledge, and poor clinical skills impede early identification, treatment, and referral. In response to these problems, an educational intervention was designed to improve practicing nurses' recognition of and responses to substance-misusing patients. Results of the pretest posttest comparison group evaluation suggest that educational interventions were influential in improving nurses' confidence in caring for substance misusing patients. Although data reflecting changes in attitudes were less compelling, the improvement in treatment optimism is a positive change that has important clinical implications.

Chief nurse executives' responses to chemically dependent nurses.

A survey completed by 195 chief nurse executives demonstrated that chemically impaired nursing practice is a commonly encountered problem. When a nurse becomes chemically dependent, numerous personal, institutional and professional implications and consequences ensue. The most powerful means of minimizing these consequences is the quick, supportive response of colleagues and administrators. Recognizing signs of chemical dependency, having standards to guide response and providing appropriate resources all support a nurse's recovery.

Is your colleague chemically dependent?

Don't shrug off signs of possible impairment--the problem is more common than you might think. Knowing how to recognize and report it can literally make the difference between life and death.

Enhanced cytotoxicity of antiviral drugs mediated by adenovirus directed transfer of the herpes simplex virus thymidine kinase gene in rat glioma cells.

The antiviral agents ganciclovir, 1-beta-D-arabinofuranosylthymine (araT), acyclovir, and 5-iodo-5'-amino-2',5'-dideoxyuridine were cytotoxic to rat C6 glioma cells expressing retrovirally transferred herpes simplex virus (HSV) type 1 thymidine kinase (TK) coding sequence, with concentrations that inhibited cell survival by 50% (IC50 values) of 0.06, 3, 13, and 23 mumol/L, respectively. In C6 cells not expressing HSV-TK, the IC50 value for ganciclovir was 140 mumol/L and a concentration of 1 mmol/L killed more than 99% of the cells. The other antiviral agents tested were less toxic in nontransduced cells. Compared with retrovirally transduced cells, transduction of C6BU1 cells with an adenovirus vector containing the coding sequence for HSV-TK (Ad.RSVtk) increased the cellular activity of the viral kinase up to 600-fold with increasing multiplicity of infection (MOl). Cells transduced with Ad.RSVtk exhibited as much as a fivefold and 12-fold decrease in IC50 value for ganciclovir and araT, respectively, compared with retrovirally transduced cells. Sensitivity to antiviral drugs increased with increasing exposure to Ad.RSVtk, with IC50 values of 0.6 and 0.005 mumol/L for araT and ganciclovir, respectively, at an MOl of 1000. These data suggest that adenoviral transfer of HSV-TK will allow the use of less toxic drugs or lower concentrations of toxic drugs such as ganciclovir for directed antitumor therapy in vivo.

Patterns of alcohol and drug use among women: focus on special populations.

Despite the growing national concern about the effect of the use of alcohol and other drugs on the health and productivity of men and women, relatively little is know about alcohol and other drug (AOD) problems in women. Because of this lack of research and the stigma associated with women who are alcoholic or drug addicted, AOD problems among women are less likely to be recognized and addressed. This article reviews patterns and consequences of AOD use among a number of special populations of women. Information about risk factors and assessment and screening are included to assist the nurse in the identification, counseling, and referral of women with AOD-related problems.

Influence of energy balance and body condition on estrus and estrous cycles in Holstein heifers.

The objective was to determine effects of energy balance and body condition on estrous behavior and estrous cycles in Holstein heifers. Before the experiment heifers were fed so body condition remained moderate or they became fat. During the 2 x 2 factorial experiment, moderate and fat heifers were in positive or negative energy balance. Heifers were fed individually twice daily, and energy balance was calculated daily. Heifers were observed for 30 min every 3 h, and all standing and mounting events were recorded for three consecutive estrous cycles. When progesterone in serum was less than 1 ng/ml, standing and mounting activity were profiled. Area, peak, and duration of activity profiles were examined among groups of heifers. Negative energy balance or fat body condition did not reduce peak or duration of estrous behavior and thus did not reduce detectability of estrus. Onset of diestrus was delayed in heifers that were fat and in negative energy balance relative to other heifers. We suggest that fat body condition, coincident with negative energy balance, may reduce accuracy of timing artificial insemination relative to ovulation and may consequently reduce fertility in cattle.