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The application of geosynthetics in infrastructure is an innovative development in concrete with the usage of geo-grid. In the plastic hinge region of Reinforced Concrete (RC) beams the additional shear reinforcement was provided by using glass fibers. The present study is carried out for the RC beam specimens, in which the additional shear confinement was given by geo-grid of various sizes was studied. In RC beams, less labor work only needed for the confinement and with the usage of geo-grid and also for the confinement the usage of geo-grid will be an effective solution. The effect of geo-grid with the glass fiber reinforced concrete has also been investigated by experimental observations and non-linear finite element simulations. Detailed 3D non-linear finite element analyses with perfect bonding of RC beam confined with geo-grid in ANSYS was carried out. One conventional beam, one conventional beam with glass fiber and three beams with a different configuration of geo-grid and volume of glass fiber were casted. For studying load–deflection behaviour, the single point loading was carried out for the geo-grid specimens and conventional beam specimens under flexure. Depend upon the usage of glass fibers and geo-grid confinement in the beam specimens, the experimental test results show that there is an enhancement in the post-yield behaviour and strength. The flexure test on beam specimens reveals that the strength of the geo-grid and its size plays a vital role in improving the load-deformation behaviour as well as crack propagation. The load–displacement behaviour and damage predicted from finite element analysis almost agree with the experimental result. Hence geo-grid seem to be an alternative material which having great ductile behaviour for the strengthening of RC beam.

The Laser Communications Relay Demonstration is NASA’s multi-year demonstration of laser communication from the Earth to a geosynchronous satellite. The mission currently has two optical ground stations (OGSs), with one in California (OGS1) and one in Hawaii (OGS2). Each ground terminal optical system consists of a high-order adaptive optics (AO) system, a laser transmit system, and a camera for target acquisition. The OGS1 AO system is responsible for compensating for the downlink beam for atmospheric turbulence and coupling it into the modem’s single mode fiber. The mission requires a coupling efficiency of 50%, which necessitates a high-order AO system. To achieve this performance, the AO system uses two deformable mirrors with one mirror correcting for low-spatial-frequency aberrations with large amplitude and a second deformable mirror correcting for high-spatial-frequency aberrations with small amplitude. Turbulence is sensed with a Shack–Hartmann wavefront sensor. To meet its performance requirements in the most stressing conditions, the system can operate at frame rates of 20 kHz. This high frame rate is enabled by the design of the real-time control system. We present an overview of both the hardware and software design of the system, and describe the control system and methods of reducing non-common path aberrations. Finally, we show measured system performance.

Significance There are numerous reasons why institutions of higher education may choose to embrace diversity. A common rationale sanctioned by the US Supreme Court is that diversity provides compelling educational benefits and is thus instrumentally useful. We show that such instrumental rationales are the predominant rationale for diversity efforts in American higher education, are preferred by White Americans and not by Black Americans, that they are expected to advantage White Americans, and that they correspond to greater racial disparities in academic achievement. Overall, these findings suggest that the rationales behind universities’ embrace of diversity have nonlegal consequences that should be considered in institutional decision making., It is currently commonplace for institutions of higher education to proclaim to embrace diversity and inclusion. Though there are numerous rationales available for doing so, US Supreme Court decisions have consistently favored rationales which assert that diversity provides compelling educational benefits and is thus instrumentally useful. Our research is a quantitative/experimental effort to examine how such instrumental rationales comport with the preferences of White and Black Americans, specifically contrasting them with previously dominant moral rationales that embrace diversity as a matter of intrinsic values (e.g., justice). Furthermore, we investigate the prevalence of instrumental diversity rationales in the American higher education landscape and the degree to which they correspond with educational outcomes. Across six experiments, we showed that instrumental rationales correspond to the preferences of White (but not Black) Americans, and both parents and admissions staff expect Black students to fare worse at universities that endorse them. We coded university websites and surveyed admissions staff to determine that, nevertheless, instrumental diversity rationales are more prevalent than moral ones are and that they are indeed associated with increasing White–Black graduation disparities, particularly among universities with low levels of moral rationale use. These findings indicate that the most common rationale for supporting diversity in American higher education accords with the preferences of, and better relative outcomes for, White Americans over low-status racial minorities. The rationales behind universities’ embrace of diversity have nonlegal consequences that should be considered in institutional decision making.

Although researchers investigating psychological contributors to educational inequality have traditionally focused on students, a growing literature highlights the importance of teachers' psychology in shaping disparities in students' educational achievement and attainment. In this review, we discuss recent advances linking teachers' attitudes, perceptions, and beliefs to inequality in students' outcomes. First, we identify specific aspects of teacher psychology that contribute to educational disparities, including teachers' biases, perceptions and expectations of students, beliefs about the nature of ability, and beliefs about group differences. Second, we synthesize mechanisms underlying the effects of teacher psychology on educational inequality, including teachers' disparate assessment of students' work and abilities, interpersonal interaction with students, and psychological impact on students. Implications for future research and interventions are discussed.

Previous Mendelian randomization (MR) studies on 25-hydroxyvitamin D (25(OH)D) and cancer have typically adopted a handful of variants and found no relationship between 25(OH)D and cancer; however, issues of horizontal pleiotropy cannot be reliably addressed. Using a larger set of variants associated with 25(OH)D (74 SNPs, up from 6 previously), we perform a unified MR analysis to re-evaluate the relationship between 25(OH)D and ten cancers. Our findings are broadly consistent with previous MR studies indicating no relationship, apart from ovarian cancers (OR 0.89; 95% C.I: 0.82 to 0.96 per 1 SD change in 25(OH)D concentration) and basal cell carcinoma (OR 1.16; 95% C.I.: 1.04 to 1.28). However, after adjustment for pigmentation related variables in a multivariable MR framework, the BCC findings were attenuated. Here we report that lower 25(OH)D is unlikely to be a causal risk factor for most cancers, with our study providing more precise confidence intervals than previously possible., Studies of the genetic association between vitamin D and cancer risk have typically been underpowered. Here the authors analyse this using Mendelian Randomisation with more than 70 vitamin D variants obtained from the UK Biobank and large-scale data from various consortia, confirming null associations between vitamin D and most cancers.

Coronavirus disease 2019 (COVID-19) has gained international attention as it poses a significant threat to global health. Currently, medical researchers are working to exhaust all strategies that may prove beneficial in combating this disease. Heat has been shown to destabilize other coronavirus strains in testing environments, and it has been hypothesized that heated air may destabilize viral pathogens in vivo as well. The present report describes the engineering of a micro-sauna prototype for the delivery of heated air. Concept formulation, process highlights, and the final prototype are all discussed. The prototype can deliver air heated to 80-90 degrees Celsius in a safe and tolerable manner. The goal of this technical report is to further encourage the study of heated air as a potential COVID-19 treatment.

The purpose of the link column frame is to provide acceptable collapse prevention performance and also easily repaired following a moderate earthquake. Linked column frame system (LCF) for steel structures was proposed by Peter Dusicka et.al (2009) with the objective of utilizing replaceable components that are strategically placed to protect the gravity load carrying system. In this paper the concept is extended to Reinforced concrete structures. The analytical studies were presented in this paper mainly focuses on the behavior of normal and link column RC frames with different connection configurations. Quasi-static cyclic load analytical results are presented and discussed for three 1:3 scaled RC frames with and without link column. Link column with various connections between the main beam and the link column i.e. rigid and hinged connection as per IS 12303-1987. With respect to experimental results, by using ANSYS software, the finite element model related to these frames is made and calibrated, and then analysis under cyclic static loading are performed. The test results showed a significant increase in the energy dissipation with a decrease in relative storey drifts for the link column frames with hinged connection. Greater amounts of energy were dissipated by the link column frame which has a hinge connection designed according to IS 12303-1987.

WFIRST Coronagraph Instrument (CGI) uses its Low Order Wavefront Sensing and Control (LOWFS/C) subsystem to maintain the coronagraph contrast in presence of wavefront disturbances from the WFIRST observatory. The Occulting Mask Coronagraph (OMC) dynamic testbed is used to demonstrate LOWFS/C performance together with the coronagraphs. We have demonstrated that LOWFS/C can maintain coronagraph contrast to better than 10-8 in presence of WFIRST-like LoS and low order WFE disturbances for both Hybrid Lyot Coronagraph (HLC) and Shaped Pupil Coronagraph (SPC) modes. However, in our previous tests the LoS disturbances simulated on the testbed were from the modeling of a single reaction wheel with a quasi-static wheel speed. In this paper we will describe the LOWFS/C LoS performance test in which the injected LoS disturbances are derived from all six reaction wheels on WFIRST, each with an independent varying wheel speed profile modeled for a typical coronagraph observational scenario. We will describe the LoS disturbances profile and testbed implementation approach. We will present the LOWFS/C LoS feedback and feed forward loops testbed performance under these realistic LoS disturbances in which we have demonstrated the LoS control that meets the CGI requirement.

Objectives: To use real-world data to better understand the temporal impact of COVID-19 on frequency of outpatient visits in urology clinics and apply a data quality framework to identify and resolve issues that could influence the validity of analyses. Methods: We examined visit trends from 157 outpatient urologic practices and 3,165 providers included in the American Urological Association Quality (AQUA) Registry, a national Qualified Clinical Data Registry designed to measure, report and improve healthcare quality and patient outcomes. As of December 2020, 50 million patient visits from 7.3 million unique patients exist in the database. We used a data quality framework to assess issues related to data completeness and timeliness. Past data lag trends were assessed to determine a temporal cutoff point that minimized lag. To account for missing data, a comprehensive visit definition that went beyond E/M (Evaluation and Management) coding was applied and compared to results using the E/M-only definition. Results: Correlating with the onset of the COVID-19 pandemic in the US in mid-March 2020, outpatient visits declined for five weeks, resulting in a 47.7% drop from the February 2020 baseline, followed by an 83.1% recovery back to baseline by July 31. Based on timeliness scores, which consider the average time between visit date and the visit data processing date from the selected practices, a 90-day buffer between data cutoff and the end of the analysis’s observation period was necessary to minimize data lag. Total patient encounters increased by more than 20% when using a more comprehensive visit definition Conclusions: The COVID-19 pandemic contributed to a reduction in outpatient visits, followed by a recovery close to baseline. Our data quality framework identified and informed key study design decisions to account for inadequate data timeliness and completeness. These methods prevented an overestimation of the true decline in patient encounters and missed patient encounters.

Residual speckles due to aberrations arising from optical errors after the split between the wavefront sensor and the science camera path are the most significant barriers to imaging extrasolar planets. While speckles can be suppressed using the science camera in conjunction with the deformable mirror, this requires knowledge of the phase of the electric field in the focal plane. We describe a method which combines a coronagraph with a simple phase-shifting interferometer to measure and correct speckles in the full focal plane. We demonstrate its initial use on the Stellar Double Coronagraph at the Palomar Observatory. We also describe how the same hardware can be used to distinguish speckles from true companions by measuring the coherence of the optical field in the focal plane. We present results observing the brown dwarf HD 49197b with this technique, demonstrating the ability to detect the presence of a companion even when it is buried in the speckle noise, without the use of any standard "calibration" techniques. We believe this is the first detection of a substellar companion using the coherence properties of light., Comment: 32 pages, 11 figures. Accepted for publication in MNRAS

We posit instructors' implicit racial bias as a factor in racial disparities in academic achievement and test the relationship between this factor, instructor lesson quality, and learners' subsequent test performance. In Study 1, white participants were assigned to the role of instructor and gave a short lesson to a learner who was either black or white. Instructors' implicit bias predicted diminished test performance on the part of black, but not white, learners. Further, instructors' anxiety and lesson quality, as rated by coders, mediated the relationship between their implicit bias and learners' test performance. In Study 2, a separate sample of non-black participants watched videos of instructors from cross-race lessons from the first experiment. Once again, instructors' implicit bias predicted diminished test performance by participants. These findings suggest that underperformance by minorities in academic domains may be driven by the effect implicit racial biases have on educators' pedagogical effectiveness.

This study assessed the solute permeability of a family of UV and moisture cured acrylates-based adhesives during in vitro ageing in pH 7.4 buffer. Acrylates have a potential role in bone fracture fixation, but their inability to allow microsolute exchange between the fractured bone surfaces may contribute to ineffective healing. Cyclic voltammetry and chronoamperometry were used to determine the diffusion coefficients for various electrochemically active probe molecules (O2, H2O2, acetaminophen, catechol, uric acid and ascorbic acid) at proprietary acrylic, urethane – acrylate and cyanoacrylate adhesives. All adhesives proved to be impermeable for up to 9 days ageing, following which a near-exponential increase in permeability resulted for all solutes. At 18 days, the diffusion coefficients were in the range of 10−5 cm2s−1 for O2 and H2O2 and 10−6 cm2s−1 for the organic solutes; no transport selectivity was seen between the latter. Adhesive joint strength showed a direct, inverse, correlation with permeability, with the more hydrophilic cyanoacrylates showing the greatest loss of strength. Adhesive permeabilisation does not appear to be compatible with the retention of bonding strength, but it serves as a new non-destructive predictor of adhesion strength change during ageing and practical use., Graphical abstract Image 1

Deformable mirrors are at the heart of any adaptive optics system. We present the results of tests of deformable mirrors from Microscale. One of the key innovations of these deformable mirrors is that the facesheet is created from a silicon on insulator (SOI) wafer with integral posts for mechanical linkage to the actuators. This dramat- ically reduces the variability of the influence function. The facesheet is bonded to an array of piezoelectric stack actuators. The actuators are currently PZT, but single crystal PMN actuators are being developed. We present results of optical and electrical tests of the performance of the DM.

Two studies investigate the relationship between racial attitude (dis)similarity and interpersonal liking for racial minorities and Whites in same-race and cross-race pairs. In nationally representative and local samples, minorities report personally caring about racial issues more than Whites do (Pilot Study), which we theorize makes racial attitude divergence with ingroup members especially disruptive. Both established friendships (Study 1) and face-to-face interactions among strangers (Study 2) provided evidence for the dissimilarity-repulsion hypothesis in same-race interactions for minorities but not Whites. For minorities, disagreeing with a minority partner or friend about racial attitudes decreased their positivity toward that person. Because minorities typically report caring about race more than Whites, same-race friendships involving shared racial attitudes may be particularly critical sources of social support for them, particularly in predominately White contexts. Understanding challenges that arise in same-race interactions, not just cross-race interactions, can help create environments in which same-race minority friendships flourish.

Accurately perceiving whether interaction partners feel understood is important for developing intimate relationships and maintaining smooth interpersonal exchanges. During interracial interactions, when are Whites and racial minorities likely to accurately perceive how understood cross-race partners feel? We propose that participant race, desire to affiliate, and racial salience moderate accuracy in interracial interactions. Examination of cross-race roommates (Study 1) and interracial interactions with strangers (Study 2) revealed that when race is salient, Whites higher in desire to affiliate with racial minorities failed to accurately perceive the extent to which racial minority partners felt understood. Thus, although the desire to affiliate may appear beneficial, it may interfere with Whites' ability to accurately perceive how understood racial minorities feel. By contrast, racial minorities higher in desire to affiliate with Whites accurately perceived how understood White partners felt. Furthermore, participants' overestimation of how well they understood partners correlated negatively with partners' reports of relationship quality. Collectively, these findings indicate that racial salience and desire to affiliate moderate accurate perceptions of cross-race partners-even in the context of sustained interracial relationships-yielding divergent outcomes for Whites and racial minorities. (PsycINFO Database Record (c) 2015 APA, all rights reserved).

The structural and non-structural components of a building is subjected to seismic forces that must have adequate strength and stiffness to minimize the inter-storey drift during structure excitations. One of the most efficient methods was proposed by Dusicka et al. [6] in the Linked Column Frame (LCF) system for steel structures. The main objective of this system is in utilizing the replaceable components that are positioned in such a way to protect the gravity load carrying system of the structure. In this paper, the concept of LCF is extends to Reinforced Concrete structures. The experimental investigation carried out in this research presents the behaviour of LCF with various connections which include rigid and hinged connection as per IS 12303-1987.Design of the LCF system should be checked to ensure that the plastic hinges developed in the links of the linked column should have reduced storey drift compared to the plastic hinges developed in the moment resisting frame system. In this experiment, cyclic load tests are carried out on a single bay frame with and without linked column. A significant reduction in the relative storey drifts along with an increase in energy dissipation of the linked column frame was noticed.

Marine renewables have made great strides in recent years. The IEC, ABS, and DNV GL continue to generate standards and recommended practices in an effort to formulate approved processes as the renewable products make their way offshore and into the market. There are many similarities in some of the processes and designs when compared to oil and gas structures, especially when it comes to moorings. However, many design areas are uniquely related to renewables, even within the same field of energy conversion (e.g. multiple types of wave energy converters). As more renewable systems are installed, the standards will continue to transition from philosophical to more prescriptive recommendations. One area in which the lines are blurred between oil and gas and renewable industries is mooring systems. The interdependency between the mooring and power generation systems plays a crucial role early in the design phase. Modeling marine energy converters and the mooring system can be complex due the variability of moving parts, and without proper attention, it may be easy to underestimate the loads and fatigue cycles to which moorings will be exposed. Moorings for these structures should incorporate existing standards and recommended practices to ensure safety and reliability. Inspection, maintenance, repair, and replacement should also be considered. As the renewable industry continues to move forward from scaled prototypes to farms of devices, the oil and gas supply chain will contemplate when to become involved from a financial and resource perspective. However, there are still hurdles within the US authorization bodies like BSEE, BOEM, FERC, NOAA, USCG, etc. to overcome. This paper addresses the existing mooring related standards and delineates areas that need further refinement or conservatism as the renewable industry moves forward with the installation of offshore energy converters.

Introduction Diagnostic laparoscopy with appendicectomy (LA) has become the accepted method of investigation and treatment of appendicitis. However, concerns remain in cases of complicated appendicitis when many advocate conversion to an open procedure (LCOA) owing to the risk of complications. The aim of this study was to look for factors that could predict complications occurring in patients undergoing appendicectomy. Methods Data inclusive of all consecutive appendicectomies over a two-year period were retrieved from the computerised theatre database. Clinical details including admission inflammatory markers, complications, severity (final pathology) and length of stay were collected from the discharge letter. Readmissions were identified as those hospital identifiers had a second set of admission dates and/or a second discharge letter. Results During the 2-year study period, 517 appendicectomies were performed. Of these, 429 patients (83%) had LA and the remaining 88 (17%) had LCOA. The LA group had a mean age of 28 years (range: 2–86 years) and a mean C-reactive protein (CRP) level of 71mg/l (range: 0–480mg/l) while the LCOA group had a mean age of 46 years (range: 11–92 years) and a mean CRP level of 162mg/l (range: 3–404mg/l). These differences in age and CRP were significant (p150mg/l (pConclusions A high preoperative CRP level predicts an increased rate of postoperative complication due to established inflammation and/or infection. This raises the question of whether we should be offering primary open appendicectomies to patients with a CRP level of >150mg/l.

Everyday interactions with same-racial/ethnic others may confer positive benefits for adolescents, but the meaning of these interactions are likely influenced by individual differences and larger structural contexts. This study examined the situation-level association between contact with same-ethnic others and anxiety symptoms among a diverse sample of 306 racial/ethnic minority adolescents (Mage = 14 years; 66 % female), based on (1) individual differences in ethnic identity centrality and (2) developmental histories of transitions in diversity between elementary, middle, and high school. The results indicated that at the level of the situation, when adolescents interacted with more same-ethnic others, they reported fewer anxiety symptoms. Further, for adolescents who had experienced a transition in school diversity, the positive benefits of contact with same-ethnic others was only conferred for those who felt that their ethnicity was very important to them. The importance of examining individual differences within larger developmental histories to understand the everyday experiences of ethnic minority adolescents are discussed.

This study examined the daily-level association between contact with same-ethnic others and ethnic private regard among 132 Asian adolescents (mean age = 14 years) attending four high schools ranging in ethnic composition diversity. The data suggest a positive daily-level association between contact with same-ethnic others and ethnic private regard for adolescents, who were highly identified with their ethnic group and who attended predominantly White or ethnically heterogeneous schools. In addition, using time lag analyses, contact with same-ethnic others yesterday was positively related to ethnic private regard today, but ethnic private regard yesterday was unrelated to contact with same-ethnic others today, suggesting that adolescents' identity is responsive to their environments. The implications of these findings for the development of ethnic identity are discussed.

Objective: The study investigates the seismic performance of reinforced concrete linked column frame system under earthquake acceleration. The utilization of concrete as link elements to resist shear and optimize its connection to the columns for shear transfer has been presented. Methods/Analysis: The seismic responses of the systems was investigated for ground motions using time history analysis for Linked Column Frame for three building models namely, 4, 7 and 10 storey building and the results were compared with the normal frame using SAP 2000. Findings: Adding linked column to the normal frame shows that the inter storey drift and base shear are effectively reduced. Results of nonlinear time history analysis show that this system has better load dissipation capabilities. Conclusion/Application: Since the replaceable links are also modelled as reinforced concrete elements the cost of construction can be greatly reduced.

Two studies examined the cognitive costs of blatant and subtle racial bias during interracial interactions. In Study 1, Black participants engaged in a 10-minute, face-to-face interaction with a White confederate who expressed attitudes and behaviors consistent with blatant, subtle, or no racial bias. Consistent with contemporary theories of modern racism, interacting with a subtly biased, compared with a blatantly biased, White partner impaired the cognitive functioning of Blacks. Study 2 revealed that Latino participants suffered similar cognitive impairments when exposed to a White partner who displayed subtle, compared with blatant, racial bias. The theoretical and practical implications for understanding the dynamics of interracial interactions in the context of contemporary bias are discussed.

This study examined how priming Whites with colorblind or multicultural approaches to diversity prior to an interracial interaction affects ethnic minorities' cognitive functioning. Although ethnic minorities did not explicitly know which prime their White partner received, ethnic minorities paired with Whites primed with colorblindness (vs. multiculturalism) showed poorer cognitive performance on the Stroop (1935) color-naming task following the interaction. Furthermore, Whites in interracial interactions primed with colorblindness exhibited more behavioral prejudice, which mediated ethnic minorities' decreased cognitive performance. These findings suggest that Whites' exposure to certain ideologies may affect the cognitive performance of the ethnic minorities they encounter.

Research on social stigma and disadvantage has flourished in the past two decades. The authors highlight the theoretical and methodological advancements that have been made, such as how experience sampling procedures and neuroscience have shed light on processes associated with social stigma. Finally, the authors discuss policy implications of historical and contemporary research on social stigma and disadvantage, as well as address ideas for future research that may be useful in creating policies and programs that promote social equality.

Pervasive representations of Blacks and Latinos as unintelligent and of Whites as racist may give rise to divergent impression management goals in interracial interactions. We present studies showing that in interracial interactions racial minorities seek to be respected and seen as competent more than Whites do, whereas Whites seek to be liked and seen as moral more than racial minorities do. These divergent impression management goals are reflected in Whites' and racial minorities' self-report responses (Studies 1a, 1b, 2, and 4) and behaviors (Studies 3a and 3b). Divergent goals are observed in pre-existing relationships (Study 2), as well as in live interactions (Studies 3a, 3b, and 4), and are associated with higher levels of negative other-directed affect (Study 4). Implications of these goals for interracial communication and misunderstandings are discussed.

We present a close companion search around sixteen known early-L dwarfs using aperture masking interferometry with Palomar laser guide star adaptive optics. The use of aperture masking allows the detection of close binaries, corresponding to projected physical separations of 0.6-10.0 AU for the targets of our survey. This survey achieved median contrast limits of Delta_K ~ 2.3 for separations between 1.2 - 4 lambda/D, and Delta_K ~ 1.4 at (2/3)lambda/D. We present four candidate binaries detected with moderate to high confidence (90-98%). Two have projected physical separations less than 1.5 AU. This may indicate that tight-separation binaries contribute more significantly to the binary fraction than currently assumed, consistent with spectroscopic and photometric overluminosity studies. Ten targets of this survey have previously been observed with the Hubble Space Telescope as part of companion searches. We use the increased resolution of aperture masking to search for close or dim companions that would be obscured by full aperture imaging, finding two candidate binaries. This survey is the first application of aperture masking with laser guide star adaptive optics at Palomar. Several new techniques for the analysis of aperture masking data in the low signal to noise regime are explored., 13 pages, 7 figures, 3 tables, accepted by ApJ

We investigated the relationship between Whites’ and ethnic minorities’ concerns about appearing prejudiced and anxiety during daily interracial interactions. College roommate pairs completed an individual difference measure of concerns about appearing prejudiced at the beginning of the semester. Then they completed measures of anxiety and perceptions of their roommates’ anxiety-related behaviors for 15 days. Results indicated that among interracial roommate pairs, Whites’ and ethnic minorities’ concerns about appearing prejudiced were related to their self-reported anxiety on a daily basis; but this was not the case among same-race roommate pairs. In addition, among interracial roommate pairs, roommates who were concerned about appearing prejudiced began to “leak” their anxiety towards the end of the diary period, as indicated by their out-group roommate who perceived their anxious behaviors as increasing across time, and who consequently liked them less. The implications of these findings for intergroup relations are discussed in this article.

This study examined whether members of low-status, stigmatized groups are less susceptible to the negative cognitive consequences of suppressing their emotional reactions to prejudice, compared with members of high-status, non-stigmatized groups. Specifically, we examined whether regulating one s emotional reactions to sexist comments—an exercise of self-regulation—leaves women less cognitively depleted than their male counterparts. We hypothesized that the greater practice and experience of suppressing emotional reactions to sexism that women are likely to have relative to men should leave them less cognitively impaired by such emotion suppression. Results were consistent with this hypothesis. Moreover, these results suggest that our social group memberships may play an important role in determining which social demands we find depleting.

We examine the processes involved in the development of interracial friendships. Using Reis and Shaver’s intimacy model, we explore the extent to which disclosure and perceived partner responsiveness influence intimacy levels in developing interracial and intraracial friendships. White and ethnic minority participants completed diary measures of self and partner disclosure and partner responsiveness every two weeks for 10 weeks about an in-group and an out-group person whom they thought they would befriend over time. The results revealed that perceived partner responsiveness mediated the relationships between both self and partner disclosure and intimacy in interracial and intraracial relationships. The implications of these results for intergroup relations are discussed.

A common ingroup identity promotes positive attitudes and behavior toward members of outgroups, but the durability of these effects and generalizability to relationships outside of the laboratory have been questioned. The present research examined how initial perceptions of common ingroup identity among randomly assigned college roommates provide a foundation for the development of intergroup friendships. For roommate dyads involving students who differed in race or ethnicity, respondents who were low on perceived intergroup commonality showed a significant decline in friendship over-time, whereas those high on perceived commonality showed consistently high levels of friendship. Similarly, participants in these dyads demonstrated a significant decline in feelings of friendship when their roommate was low in perceived commonality but not when their roommate was high in perceived commonality. These effects were partially mediated by anxiety experienced in interactions over-time. The implications of a common identity for intergroup relationship development are discussed.

The social psychological literature maintains unequivocally that interracial contact is stressful. Yet research and theory have rarely considered how stress may shape behavior during interracial interactions. To address this empirical and theoretical gap, the authors propose a framework for understanding and predicting behavior during interracial interactions rooted in the stress and coping literature. Specifically, they propose that individuals often appraise interracial interactions as a threat, experience stress, and therefore cope—they antagonize, avoid, freeze, or engage. In other words, the behavioral dynamics of interracial interactions can be understood as initial stress reactions and subsequent coping responses. After articulating the framework and its predictions for behavior during interracial interactions, the authors examine its ability to organize the extant literature on behavioral dynamics during interracial compared with same-race contact. They conclude with a discussion of the implications of the stress and coping framework for improving research and fostering more positive interracial contact.

Jobs, social group memberships, or living arrangements lead many people to interact every day with another person from a different racial background. Given that research has shown that interracial interactions are often stressful, it is important to know how these daily interactions unfold across time and what factors contribute to the success or failure of these interactions. Both members of same-race and mixed-race college roommate pairs completed daily questionnaires measuring their emotional experiences and their perceptions of their roommate. Results revealed that roommates in mixed-race dyads experienced less positive emotions and intimacy toward their roommates than did roommates in same-race dyads and that the experience of positive emotions declined over time for ethnic minority students with White roommates. Mediation analyses showed that the negative effects of roommate race were mediated by the level of intimacy-building behaviors performed by the roommate. Implications for future research and university policies are discussed.

We demonstrated that a self—other attributional bias impedes interracial friendship development. Whites were given the opportunity to become friends with a White or Black participant. Whites indicated how interested they were in becoming friends and how concerned they were about being rejected as a friend. They also indicated how interested they thought the other person was in becoming friends and how concerned they thought the other person was about being rejected as friend. Results revealed that lower-prejudice Whites made divergent explanations for the self and other when the potential friend was Black, whereas higher-prejudice Whites did not. Prejudice level did not influence the type of explanations made when the potential friend was White. Implications for interracial friendship development are considered.

Most of the research on intergroup anxiety has examined the impact of people's own anxiety on their own outcomes. In contrast, we show that in intergroup interactions, one's partner's anxiety is just as important as one's own anxiety (if not more important). Using a diary study among college roommates, we show that partners' anxiety predicts respondents' anxiety across time on a daily basis, as well as respondents' interest in living together again the next year. We discuss the importance of taking a relational approach to understanding intergroup interactions.

Two experiments (140 pigs in Exp. 1; 120 pigs in Exp. 2) evaluated a marine-based hydrolyzed protein source, (Peptiva Vitech Bio-Chem, San Fernando, CA) as a replacement for spray dried plasma protein (SDPP) in phase I weanling pig diets. Pigs (19 ± 4 d of age) were fed diets with protein supply based mainly on soy protein, or similar diets supplemented with SDPP or Peptiva after weaning for 7 to 10 d. The SDPP and Peptiva were supplemented at 3 and 6%, respectively, in Exp.1 and 1.5 and 3% in Exp. 2. In Exp. 1, pigs fed diets with SDPP had greater (P 0.05). A third experiment using 48 pigs investigated supplementation of SDPP or Peptiva in phase I diets on diet digestibility and N balance. Results indicated that 6% dietary inclusion of either specialty protein had no impact on N retention, digestibility, or protein biological value (P = 0.22 to 0.39) when compared with the control diet. Alteration in diet digestibility is not an important contributing factor to improved growth performance when SDPP is supplemented in phase I pig diets. The hydrolyzed protein source was acceptable as a general protein supplement, but did not elicit phase I growth stimulation typically observed with SDPP.

SUMMARY Chromium has been considered by many nutritionists as an essential nutrient for animals and humans. Research on the use of Cr from organic sources in poultry is limited. Two experiments were conducted to determine the effects of dietary addition of 0, 200, 400, or 800 ppb Cr as chromium propionate on growth performance and carcass traits in 0- to 42- or 0- to 49-d-old broilers. The results of these experiments indicate that Cr as chromium propionate improved feed efficiency in the later phases of growth and decreased mortality in one experiment but not another. Also, chromium propionate supplementation had no effect on carcass traits.

A study was conducted to determine whether direct-fed microbials (DFM) could be used to increase digestibility and minimize the risk of acidosis associated with feeding an increase in the amount of starch fed to horses. Fifteen mature Thoroughbred geldings were randomly assigned to 1 of 3 treatments in a 3 x 3 Latin square design balanced for carryover effects. Within each 26-d period, horses were offered grass hay + low-starch concentrate (LS; 1.2 g of starch x kg of BW(-1) x meal(-1)) from d 1 to 13 and then were abruptly changed to hay + high-starch concentrate (HS; 2.4 g of starch.kg of BW(-1)x meal(-1)) on d 14 continuing through d 26. The DFM treatments were offered in concentrate pellets at a target dosage of 10(8) cfu/(50 kg of BW x d) as follows: no DFM (CON; control), Lactobacillus acidophilus (LAC1; single-species DFM), or a mixture of L. acidophilus, Lactobacillus casei, Bifidobacterium bifidum, and Enterococcus faecium (LAC4; multiple-species DFM). Total feces were collected over 72 h from d 11 to 13 (LS; low dietary starch collection), from d 15 to 17 (AC; abrupt change in dietary starch collection), and at the end of each experimental period, from d 24 to 26 (HS; high dietary starch collection). Data collected consisted of total DM intake and fecal output, fecal pH, fecal acetate and propionate concentrations, and viable numbers of DFM in the feed. With the exception of Fe digestibility, there were no starch x DFM interactions. There was an effect of starch level (P 0.10). Horses supplemented with LAC4 had increased ether extract (P < 0.05) and a tendency for decreased Na (P < 0.10) digestibilities compared with CON horses. All DFM-supplemented horses had increased Cu (P < 0.05) and Fe and numerically increased Zn digestibilities compared with CON horses. Fecal pH decreased (P < 0.05), and fecal propionate concentration increased (P < 0.05) as dietary starch content changed from LS to HS. There was a tendency for elevated fecal pH (P < 0.10) in LAC1 horses compared with CON horses. These results confirm that increasing starch in the equine diet can enhance nutrient digestibility of the diet. Supplementing equine diets with either a single or mixed strain direct-fed lactic acid bacteria had limited effects on nutrient digestibility or on reducing the risk of acidosis associated with feeding high-starch concentrates to horses. The potential response of DFM supplementation should be evaluated when a more acute acidotic state is induced in horses than in the current study.

The United States is becoming increasingly diverse, yet interracial contact continues to be awkward, if not stressful, for many. Indeed, recent research suggests that individuals often exit interracial interactions feeling drained both cognitively and emotionally. This article reviews research examining how interracial encounters give rise to these outcomes, zeroing in on the mediating role of self-regulation and the moderating influence of prejudice concerns. Given that interracial contact may be the most promising avenue to prejudice reduction, it is important to examine factors that undermine positive interracial contact experiences, as well as those that facilitate them.

An experiment was conducted to determine the interactive effects of Zn, Cu and Mn addition to diets of 0 to 14-d old broilers on growth performance, bone breaking strength, bone ash percentage and tissue mineral concentrations. Two levels of Zn (0 or 75 ppm, as Zn sulfate), 2 levels of Mn (0 or 100 ppm, as Mn sulfate) and 2 levels of Cu (0 or 7 ppm, as Cu sulfate) were supplemented to corn-soybean meal diets in a 2×2×2 factorial arrangement. Each treatment had 6 replications with 5 chicks each and the initial and final BW were 46 and 382 g. Daily gain, daily feed intake, gain:feed, bone breaking strength and bone and pancreatic Zn concentrations were increased (p