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101.
Research has identified numerous mechanisms through which perceived social isolation and lack of social support negatively impact health. Little research attention has been dedicated to factors that influence the development of social networks, which have the potential to decrease perceptions of social isolation and provide social support. There is mixed evidence concerning the availability of supportive social networks for Latinos in the US. This study explores trauma-exposed Latina immigrants’ experiences of social isolation in the US and its perceived causes. Twenty-eight Latina immigrant women participated in an interview about traumatic experiences. Informal help seeking and the availability of friendships in the US were also queried. Frequent comparisons between experiences in their home countries and in the US shaped the emerging themes of social isolation and lack of social support. Women reported feeling lonely, isolated, closed-in, and less free in the US due to family separation and various obstacles to developing and maintaining relationships. Socioeconomic, environmental, and psychosocial barriers were offered as explanations for their limited social networks in the US. Understanding experiences of social isolation as well as barriers to forging social networks can help inform the development of social support interventions that can contribute to improved health among Latinos.  相似文献   
102.
Grounded theory provided a framework for examining 25 acculturating American Indian college students, 12 relatives of acculturating American Indians, and 7 postsecondary administrators. Acculturation was defined as the transformative process resulting from the integration of tribal culture and predominately White culture. Data sources included individual interviews, focus groups, and artifact analysis. The 16 emergent themes form an acculturation theory centered on a strength‐based acculturation process affecting American Indians’ transition to predominately White postsecondary settings.  相似文献   
103.
In Colombia, as in other Latin American countries, current population genetics research is based on the understanding that Colombians constitute a mestizo nation, given the admixture process that took place between Africans, Amerindians, and Europeans during colonial times. The mestizo is a pervasive category used by geneticists to conduct, organise, and publish research studies that deal with the continent's peopling process and the genetic makeup of its contemporary population(s). It is also the dominant imaginary for the Colombian population and a key nation-building ideology. By tracing how this category moves and is used across four Colombian genetics laboratories, it is possible to discern that despite its apparently clear-cut boundaries, the mestizo is contingent, contested, and flexible, allowing for multiple understandings and usages. This flexibility and multiplicity are visible in the quantification of genetic ancestry, the divisions of geographical location, and the understanding of gender. Such understandings allow one to think about a homogeneous nation (inclusive) that is simultaneously heterogeneous (exclusive); they provide multiple but not necessarily contradictory possibilities of being mestizo, allowing the coexistence of images of the nation that could otherwise seem contradictory; and they permit navigation around contested terms such as race, while simultaneously thinking of mixed races or racialised individuals. Finally, these flexible and multiple constructions of the mestizo (re)produce various subjects as ‘other’, whether they are women, the Indigenous, the black/dark, or the poor.  相似文献   
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105.
This work aims to compare in patients with anorexia nervosa, bulimia nervosa, and control subjects: (a) body checking types, frequency, and parts; (b) prevalence of body avoidance and the most checked body parts; (c) body checking cognitions. Eighty-five outpatients with eating disorders (ED) and 40 controls filled out validated body checking and cognition questionnaires. ED patients, especially bulimia nervosa, check their bodies more than do the control subjects. The most checked area was the belly. The most frequent means of body checking was mirror checking, while the most avoided was weighing. The reasons that participants in the various study groups check their bodies seem to differ. Given the importance of body checking in the etiology and maintenance of EDs, it is important that clinicians consider this behavior, as well as the factors that lead to checking/avoidance in the different eating disorder subtypes, so that treatment may be more specific.  相似文献   
106.
Object manipulation depends on a refined control of grip force (GF) and load force (LF). After a brain injury, the GF control is altered in the paretic hand but what happens with the non-paretic hand is still unclear. In this study, we compared the GF control and GF–LF coordination of the non-paretic hand of 10 stroke individuals who suffered right brain damage (RBD) and 10 who suffered left brain damage (LBD), with 20 healthy individuals during lifting and oscillation task, using an instrumented object. GF was recorded with a force transducer, and LF was estimated from the object weight and acceleration. Overall, the ipsilesional hand of stroke individuals, independent of the lesion side, presented similar GF control and GF–LF coordination. However, LBD individuals took longer to start lifting the object, which may be due to the need of more time to obtain somatosensory information from the contact with the object. The findings indicate that stroke individuals preserve their ability to control and coordinate GF and LF when using their ipsilesional hand for object manipulation and the left hemisphere may play an essential role in the processing of somatosensory information needed for the GF control.  相似文献   
107.
Norepinephrine receptors have been studied in emotion, memory, and attention. However, the role of alpha1-adrenergic receptors in fear conditioning, a major model of emotional learning, is poorly understood. We examined the effect of terazosin, an alpha1-adrenergic receptor antagonist, on cued fear conditioning. Systemic or intra-lateral amygdala terazosin delivered before conditioning enhanced short- and long-term memory. Terazosin delivered after conditioning did not affect consolidation. In vitro, terazosin impaired lateral amygdala inhibitory postsynaptic currents leading to facilitation of excitatory postsynaptic currents and long-term potentiation. Since alpha1 blockers are prescribed for hypertension and post-traumatic stress disorder, these results may have important clinical implications.Although norepinephrine (NE) has been widely studied as an important modulator of memory and emotion, comparatively little is known about the role of NE in amygdala-dependent Pavlovian fear conditioning, a major model for understanding the neural basis of fear learning and memory. In fear conditioning, an emotionally neutral conditioned stimulus (CS; i.e., tone) is temporally paired with an aversive unconditioned stimulus (US; i.e., footshock). After very few pairings, a lasting, robust CS–US association is acquired, and the CS elicits stereotypical defensive responses, including behavioral freezing (Blanchard and Blanchard 1969; Bolles and Fanselow 1980).The lateral nucleus of the amygdala (LA) is a key structure underlying fear conditioning (LeDoux 2000). Convergence of CS and US information in LA is believed to play an important role in initiating synaptic plasticity. Long-term potentiation (LTP)-like changes in LA CS processing are critical for fear memory storage (LeDoux 2000; Blair et al. 2001; Maren 2001; Walker and Davis 2002). LA receives auditory CS inputs from the thalamus and cortex and connects directly and indirectly with the central nucleus of the amygdala to control expression of Pavlovian fear responses.Of the noradrenergic receptor subtypes, alpha1 receptors have received the least attention in fear conditioning. LA receives NE-containing inputs from the locus coeruleus that fire tonically and phasically in response to aversive stimuli like footshock (Pitkänen 2000; Tanaka et al. 2000; Aston-Jones and Cohen 2005). Alpha1-adrenergic receptors are expressed in LA, most likely on both excitatory and inhibitory neurons (Jones et al. 1985; Domyancic and Morilak 1997). Alpha1 receptor activation stimulates GABA-mediated miniature inhibitory postsynaptic currents in LA (Braga et al. 2004), suggesting that alpha1 receptors contribute to inhibition in fear conditioning pathways. Several elegant experiments recently demonstrated that LA inhibition gates synaptic plasticity necessary for fear conditioning, and this inhibitory gate can be influenced by neuromodulators including NE (Stutzmann and LeDoux 1999; Shumyatsky et al. 2002; Bissière et al. 2003; Shaban et al. 2006; Shin et al. 2006; Tully et al. 2007). However, the role of alpha1 receptor activity in gating amygdala LTP and fear learning has never been examined.We hypothesized that alpha1 blockers would facilitate fear learning, possibly by impairing LA inhibition and facilitating LA LTP. To test this hypothesis, we injected rats with terazosin, a selective alpha1-adrenergic receptor antagonist, systemically or directly into LA before or after fear conditioning. We examined in vitro the effect of terazosin on LA pyramidal cell inhibitory postsynaptic currents (IPSCs) and excitatory postsynaptic currents (EPSCs) in response to fiber stimulation of the thalamic CS input pathway to LA, as well as the effect of terazosin on LA LTP in this same pathway. We found that intra-LA terazosin facilitated fear conditioning when injected before but not after training. We also found that terazosin impaired IPSCs in LA pyramidal cells, leading to facilitated EPSCs and LTP.Behavioral experiments were conducted on adult, male Sprague–Dawley rats (Hilltop Laboratory Animals) weighing approximately 300 g upon arrival. Rats were individually housed, maintained on a 12/12 h light/dark schedule, and allowed free access to food and water. Testing was conducted during the light phase. All procedures and experiments were approved by NYU''s Animal Care and Use Committee.For systemic injections, terazosin (20 mg/kg; Sigma) was dissolved in saline and injected intraperitoneally (i.p.) 30 min prior to conditioning in 1 mL/kg volume. For bilateral infusions, terazosin (125 ng/0.25 µL) was dissolved in aCSF and infused into the LA at 0.1 µL/min 30 min prior to or immediately after fear conditioning. Bilateral guide cannulae (22 gauge; Plastics One) aimed at LA (−3.3 mm anterior, 5.2 mm lateral, −7 mm dorsal to bregma) were surgically implanted as previously described (Sotres-Bayon et al. 2009). Rats were given at least 7 d to recover from surgery before testing. For infusions, dummy cannulae were removed, and infusion cannulae (28 gauge, +1 mm beyond guides) were inserted into guides. Infusion cannulae were connected to a 1.0 μL Hamilton syringe via polyethylene tubing. Infusion rate was controlled by a pump (PHD22/2000; Harvard Apparatus), and infusion cannulae were left in place for an additional 60 sec to allow diffusion of the solution away from the cannula tip, then dummy cannulae were replaced. Upon completion of the experiment, rats were euthanized, brains removed, and cannulae placements verified histologically as previously described (Sotres-Bayon et al. 2009).Two contexts (A and B) were used for all testing as previously described (Schiller et al. 2008). The grid floors in Context B were covered with black Plexiglas inserts to reduce generalization. No odors were used and chambers were cleaned between sessions. CSs were 30 sec, 5 kHz, 80 dB tones, and USs were 1 sec, 0.8 mA scrambled electric footshocks. Experiments consisted of two phases separated by 48 h: (1) fear conditioning in Context A and (2) long-term memory (LTM) test in Context B. On Day 1, rats were placed in Context A, allowed 5 min to acclimate, and then received three CS–US pairings separated by variable 5 min ITIs. On Day 3, rats were placed in Context B and allowed 5 min to acclimate before receiving one CS-alone presentation.The index of fear in behavioral experiments was “freezing,” the absence of all non-respiratory movement (Blanchard and Blanchard 1971; Fanselow 1980). Following testing, freezing was manually scored from DVDs by a scorer blind to group specification. Graphs represent group means ± SEM. Statistical analysis was conducted with GraphPad Prism.Whole-cell electrophysiological recordings were obtained from LA pyramidal cells using in vitro coronal slices from rats aged P21–P30 d as described in Cunha et al. (2010). Terazosin was bath-applied for 10 min to achieve stable responses before testing. The cells were voltage-clamped using an Axopatch 200B amplifier at −35 mV for recording EPSCs and IPSCs. Synaptic responses were evoked with sharpened tungsten bipolar stimulating electrodes. Internal capsule fibers containing thalamic afferents were stimulated for paired-pulse facilitation (PPF) (ISI = 50 msec; 0.1 Hz) using a photoelectric stimulus isolation unit with a constant current output. Cells were rejected if access resistance (8–26 MΩ) changed more than 15%. Signals were filtered at 2 kHz and digitized (Digidata 1440 A; Axon Instruments), and peak amplitude, 10%–90% rise time, and IPSC decay time constants were analyzed offline using pCLAMP10.2 software (Axon Instruments).Brain slices for LTP experiments were prepared from rats aged 3–5 wk as in Johnson et al. (2008) and maintained on an interface chamber at 31°C. Glass recording electrodes (filled with aCSF, 5 MΩ resistance) were guided to LA neurons. Bipolar stainless steel stimulating electrodes (75 kΩ) were positioned medial to LA in internal capsule fibers. Orthodromic synaptic potentials were evoked via an isolated current generator (Digitimer; 100 μsec pulses of 0.3–0.7 mA). Evoked field potentials were recorded with an Axoclamp 2B amplifier and Axon WCP software (Axon Instruments). Data were analyzed offline using WCP PeakFit (Axon Instruments). LTP was measured as a change in evoked field potential amplitude.Baseline responses were monitored at 0.05 Hz for 30 min with a stimulus intensity of 40%–50% of maximum fEPSP before LTP induction. Terazosin (10 µM) was superfused for 15 min, and then LTP was elicited by three tetanus trains (100 Hz × 1 sec, 3 min ITI) with the same intensity and pulse duration as the baseline stimuli. In one experiment, picrotoxin (PTX; 75 µM) was present in the perfusion solution to block fast GABAergic signaling.  相似文献   
108.
The present studies examined the extent to which (a) communalism, familism, and filial piety would pattern onto a single family/relationship primacy construct; (b) this construct would be closely related to indices of collectivism; and (c) this construct would be related to positive psychosocial functioning and psychological distress. In Study 1, 1,773 students from nine colleges and universities around the United States completed measures of communalism, familism, and filial piety, as well as of individualistic and collectivistic values. Results indicated that communalism, familism, and filial piety clustered onto a single factor. This factor, to which we refer as family/relationship primacy, was closely and positively related to collectivism but only weakly and positively related to individualism and independence. In Study 2, 10,491 students from 30 colleges and universities in 20 U.S. states completed measures of communalism, familism, and filial piety, as well as of positive psychosocial functioning and psychological distress. The family/relationship primacy factor again emerged and was positively associated with both positive psychosocial functioning and psychological distress. Clinical implications and future directions for the study of cultural values are discussed.  相似文献   
109.
The athlete's psychological profile is one of the most studied areas in sport psychology, but there is no consensus in this area. The purpose of this study was to elaborate and validate a scale to measure and classify athletes into a Idiocentric-Alocentric profile. The method was split in two phases: a) Items elaboration and theoretical model and b) Validation. Qualitative analyses were performed during the first phase and factorial analysis and Cronbach's Alpha were used to validate the instrument. The final instrument was composed by 27 items and the factorial structure showed three factors for Idiocentrism (Self-Realization & Competitiveness, Hedonism, Team Emotional Distance and a second order factor - Idiocentrism Level) and one factor for the Alocentrism (Alocentrism Level). It was concluded that the pattern and consistency of the results indicate that this inventory could be used as a reliable research tool in Brazilian sports context.  相似文献   
110.
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