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Background Studies on occupational stress have shown that police officers (POs) are vulnerable to the effects of stress, demonstrated by increased risk of cardiometabolic diseases, which may be exacerbated by the use of maladaptive coping techniques. Although there is an abundance of research pertaining to stress in POs, little research has been done to assess a subset of law enforcement, crime scene personnel (CSP). Aims To assess the stress levels, anxiety levels and coping mechanisms of CSP across the state of Texas. Methods The Perceived Stress Scale (PSS), Police Stress Questionnaire (PSQ), and the Distress Thermometer were used to measure stress levels, the State-Trait Anxiety Inventory (STAI) was utilized to measure anxiety, and the Brief COPE questionnaire was used to measure coping mechanisms. Results CSP (N = 76) surveyed reported both low stress and low anxiety for all measures used, with males reporting slightly higher stress and anxiety than females. Differences in coping mechanisms used by CSP were observed between males and females, but not between sworn officers and civilian workers. Female CSP used emotional support (P < 0.01), instrumental support (P < 0.05) and positive reframing (P < 0.05) as a coping mechanism significantly more often than males. Conclusions The results suggest that adaptive coping mechanisms should be emphasized by those supervising CSP. With little research available on CSP, further evaluation of the type of stressors experienced by these members of law enforcement is warranted. [ABSTRACT FROM AUTHOR]

Within Santa Margarita Ecological Reserve (SMER), southern California, an ~ 108 Ma diorite-gabbro pluton has weathered spheroidally resulting in the formation of concentric rindlets, i.e., a rindlet zone, around an unaltered ellipsoidal core of the parent rock. To our knowledge little is known about how spheroidal weathering is produced in Mediterranean climates like that characteristic of portions of the Peninsular Ranges. Hence, we undertook a detailed study aimed at determining the textural and chemical changes associated with the spheroidal weathering of the diorite-gabbro pluton. The parental spheroidally weathered corestone is characterized by a hypidomorphic-granular texture, and consists primarily of plagioclase, amphibole, and biotite, along with minor amounts of pyroxene and quartz. Within the corestone, sericite, and uncommonly, calcite and chlorite, replace plagioclase. The latter mineral also infrequently replaces portions of amphibole and biotite. Such alteration products are derived from sub-solidus deuteric alteration of the pluton. XRD clay mineral analysis of the 13 rindlets indicates the presence of mostly kaolinite and vermiculite, and a far lesser volume of green smectite. Thin section study of rindlet samples suggests that vermiculite is derived from the weathering of biotite, the most extensively altered mineral in the rindlet zone. Such alteration is paralleled by statistically significant losses of K mass across the rindlet zone. In addition, statistically significant losses of Ca and Na mass across the rindlet zone, likely reflect conversion of sericite to kaolinite. In contrast, the absence of statistically significant losses of Mg, Fe, and Mn over most of the rindlet zone, implies that fluids were mostly oxidizing, and that any Mg leached from amphibole was likely fixed within smectite, while leached Fe and Mn precipitated out as oxides or oxyhydroxides. Though calcite was present in the corestone, its absence in the rindlets indicates that fluids were sufficiently acidic to dissolve and remove it. Previous studies have shown that spheroidal weathering occurs when volume expansion produced by a positive ΔV of reaction builds up internal elastic strain energy in the rock. For example, this type of reaction occurs when iron oxidizes within biotite resulting in an expansion of d(001) from 10 Å to 10.5 Å, or when biotite is transformed into vermiculite leading to an expansion of d(001) from 10 Å to 14 Å. Data presented here suggest that the conversion of biotite to vermiculite, and the resulting positive ΔV produced the spheroidal fracturing of the corestone at SMER. Hence, these and other data discussed in this paper suggest that the weathering of biotite is the primary driving force in the formation of spheroidally weathered corestone in the Mediterranean climate of the Peninsular Ranges. [ABSTRACT FROM AUTHOR]

Combined mental and physical stress is associated with exacerbated cortisol production which may increase risk for the progression of cardiovascular disease in individuals working in high-stress occupations (e.g., firefighters, military personnel, etc.). Carbohydrate (CHO) ingestion prior to physical stress may attenuate cortisol concentrations. This project was the first to investigate the effect of CHO ingestion on cortisol response from combined mental and physical stress. 16 men 21-30 years old were randomly assigned a 6.6% CHO beverage or non-CHO control 15 min prior to performing a dual-concurrent-stress challenge. This consisted of physical stress (i.e., steady state exercise) combined with computerized mental challenges. Blood was sampled 70, 40, and 15 min before exercise, immediately at onset of exercise, 10,20,30,35 min during exercise, and 15,30,45, and 60 min after exercise. There was a significant main effect for treatment regarding mean cortisol concentrations (F=5.30, P=0.0219). The total area under curve for cortisol was less when CHO was ingested (T7 = 4.07, P=0.0048). These findings suggest that CHO ingestion immediately prior to combined mental and physical stress may attenuate cortisol responses. [ABSTRACT FROM AUTHOR]

The influence of psychological states on physiological responses during exercise is of considerable importance to individuals for which the efficiency of energy production is critical to occupational performance. Numerous studies have shown that aerobic fitness is associated with enhanced cardiovascular efficiency at rest and that responses to mental stress demonstrate evidence of increased sensitivity (relative increase in HR response) and enhanced efficiency (a decrease in absolute HR). However, the effect of aerobic fitness and its impact on cardiorespiratory (CR) responses to psychological stress during exercise has not been investigated. Therefore, the purpose of this study was three-fold; (1) to examine during exercise, anxiety, effort sense, and CR responses to a mental challenge, (2) to examine anxiety and heart rate (HR) responses from rest to exercise with mental challenge between below average fitness (Low Fit) and well-above average fitness (Hi Fit) individuals (exercising at similar relative intensities), and (3) to examine anxiety, effort sense, and CR responses of Low Fit and Hi Fit individuals to a mental challenge during exercise at a similar relative intensity. Twelve Low Fit and eleven Hi Fit subjects participated in two, 32-minute cycle ergometer rides at 65% Of VO2max. In the mental challenge condition (MCC), subjects rode while participating in mentally challenging tasks (Stroop Color-Word task and mental arithmetic) from mm 6 to mm 14 of the protocol. In the no mental challenge condition (NMCC), subjects exercised at the same intensity and duration without a stressor. Subjects were counter-balanced between fitness levels and condition. HR, VE, VE/VO2, RR, VO2, RER, effort sense (RPE), and state anxiety (SAl) were assessed at 5, 14, 24, and 30 mm. SAl was also assessed at -5 mm before exercise and after 15 mm of recovery. In addition, the NASA task load index (NTLX) was used to assess perceived overall workload. SAl increased significantly at 14 mm in the MCC. NTLX scores indicated that the MCC was perceived as a greater overall workload. Furthermore, HR, VE, VE/VO2, and RR were significantly elevated during the mental challenge condition at 14 mm. The Hi Fit subjects tended to respond to the dual stress of exercise and mental challenge with a relative increase in HR, while absolute HR was similar in both groups. An examination of fitness group differences revealed that SAL and NTLX were similar for Low Fit and Hi Fit subjects when exercising in the MCC, although, Hi Fit subjects demonstrated lower HR responses from 6 mm to 14 mm. VE, VE/VO2, and RR were similar for Low Fit and Hi Fit subjects. These results suggest that psychological stress during physical activity can exacerbate cardiorespiratory responses and suggests that factors that impact CR adjustment to mental challenge from resting baseline may differ from the factors that impact CR adjustment to mental challenge during exercise. Finally, fitness level attenuates HR and may attenuate additional cardiorespiratory responses while participating in a dual stress condition, of exercise and mental challenge. [ABSTRACT FROM AUTHOR]

An exerpt from the "Journal of the Tennessee Academy of Science" 22, No. 2 in the 1947 issue is presented.

Nitric oxide (NO) is a signaling molecule in humans that is known for its' vasodilative properties. L-arginine alpha-ketoglutarate is a natural product that has been shown to enhance the release of NO in the body. NO stimulators (NOS) are being marketed as being able to reduce fatigue associated with resistance training. PURPOSE: Therefore, the purpose of this study was to investigate L-arginine alpha-ketoglutarate on muscular strength and endurance during upper and lower body resistance exercise. METHODS: Twenty one active men (age = 20.04 ± 0.52) ingested L-arginine alpha-ketoglutarate (3-g) or a placebo (PL) 45 minutes prior to exercise in a randomized, double-blind crossover design. Participants refrained from supplement intake 72 hours and strenuous exercise 48 hours prior to the testing session, respectively. Initially, resting heart rate, blood pressure (BP) and lactate (LA) were obtained followed by one-repetition maximum (1-RM) testing on the barbell bench press and leg press. Upon determination of 1-RM, participants completed repetitions to failure at 60% of 1-RM. Heart rate, BP, LA, and rating of perceived exertion (RPE) were measured after the final repetition. RESULTS: Analysis revealed a significantly greater 1-RM bench press in the NOS condition compared to the PL (p = .04), however there was no difference between conditions for the 1-RM leg press. Additionally, no significant difference was seen between the PL and NOS treatments for upper or lower body muscular endurance. Measures of RPE, LA, BP, and heart rate were similar at the end of the muscular endurance set for both the upper and lower body exercise with NOS compared to PL. CONCLUSIONS: The results suggest that NOS may provide some ergogenic benefit during 1-RM on the bench press; however this ergogenic effect was not evident during maximal (1-RM) exertion on the leg press and muscular endurance exercises for the upper or lower body. PRACTICAL APPLICATION: In conclusion, NOS supplementation may provide some ergogenic benefits for upper body muscular strength (1-RM) on the bench press, yet this needs to be further explored. [ABSTRACT FROM AUTHOR]

Reconstitution of Semliki forest virus infected nude mice with spleen cells from their immunocompetent nu/+ litter mates resulted in an abolition of the otherwise persistent brain virus, production of anti-SFV IgG, and development of normally absent brain pathology. The brain pathological changes, including demyelination, seem to be mediated by T cells, and are maximum 14 days after sensitization of the reconstituting spleen cells. Sensitization of the spleen cells 7 days before transfer to the nude mice results in pathological changes advanced by about 8 days, compared to reconstitution with unsensitized cells. The involvement of T cells in the virus-induced pathology is discussed. [ABSTRACT FROM AUTHOR]

Infections with the avirulent (A7/74) strain of Semliki Forest virus which causes primary demyelination of the central nervous system in mice have been studied further in nude athymic (nu/nu) mice and their immunocompetent (nu/+) litter mates to measure the production of immunoglobulins. This has been done by radial immunodiffusion and enzyme-linked immunosorbent assays. Half the nude mice examined were able to synthesize specific IgG but at levels 1,000-fold lower than their nu/+ littermates. The majority of nude mice reconstituted with spleen cells from nu/+ mice 1 day before infection with virus were able to synthesize specific IgG nearly as well as the nu/+ animals. [ABSTRACT FROM AUTHOR]

Abrupt alterations in the 24-h light : dark cycle, such as those resulting from transmeridian air travel, disrupt circadian biological rhythms in humans with detrimental consequences on cognitive and physical performance. In the present study, a jetlag-simulated phase shift in photoperiod temporally impaired circadian peaks of peripheral clock gene expression in racehorses but acutely enhanced athletic performance without causing stress. Indices of aerobic and anaerobic capacities were significantly increased by a phase-advance, enabling prolonged physical activity before fatigue occurred. This was accompanied by rapid re-entrainment of the molecular clockwork and the circadian pattern of melatonin, with no disturbance of the adrenal cortical axis, but a timely rise in prolactin, which is a hormone known to target organs critical for physical performance. Subsequent studies showed that, unlike the circadian pattern of melatonin, and in contrast to other species, the daily rhythm of locomotor activity was completely eliminated under constant darkness, but it was restored immediately upon the reintroduction of a light : dark cycle. Resetting of the rhythm of locomotion was remarkably fast, revealing a rapid mechanism of adaptation and a species dependency on light exposure for the expression of daily diurnal activity. These results show that horses are exquisitely sensitive to sudden changes in photoperiod and that, unlike humans, can benefit from them; this appears to arise from powerful effects of light underlying a fast and advantageous process of adjustment to the phase shift. [ABSTRACT FROM AUTHOR]

Abstract Aims: The aim of this study was to develop a polyacrylamide gel electrophoresis (PAGE) method for the rapid separation of 16S rRNA PCR amplicons from aetiological agents of acute meningitis. Methods and Results: Blood samples from 40 patients with suspected acute meningococcal meningitis were examined for the presence of causal agents, including Neisseria meningitidis employing two methods: (i) broad-range 16S rRNA PCR in conjunction with PAGE and automated sequencing and (ii) species-specific PCR employing ABI TaqMan technology for N. meningitidis . Analysis of clinical specimens employing 16S rRNA PCR yielded 33/40 (82·5%) positive for the presence of bacterial DNA. Species-specific PCR yielded 30/40 (75%) clinical specimens positive for N. meningitidis . Prior to separation by PAGE, only 6/33 (18·2%) amplicons were able to be identified by sequence analysis, the remaining amplicons (n =27) did not yield an identification due to the presence of mixed 16S rRNA PCR amplicons. Following separation, amplicons were re-amplified and sequenced, yielding 24/27 (88·9%) positive for N. meningitidis and three specimens positive for Acinetobacter sp., Staphylococcus aureus and Streptococcus pneumoniae . One specimen was positive for both N. meningitidis and Streptococcus spp. and another specimen was positive for N. meningitidis and Pseudomonas sp., by broad-range PCR. Seven clinical specimens were negative for N. meningitidis and other eubacteria using both detection techniques. Conclusions: Clinical specimens including blood and cerebrospinal fluid from patients with suspected acute bacterial meningitis, may become contaminated with commensal skin flora, resulting in difficulties in downstream sequencing of pathogen plus contaminant DNA. This study allows for the rapid separation of amplified pathogen from contaminant DNA. Significance and Impact of Study: This study demonstrated the usefulness of the rapid separation of multiple 16S rRNA PCR... [ABSTRACT FROM AUTHOR]

The article provides eleven abstracts of published medical research. Topics include atypical antipsychotic agents in treating schizophrenia, staging in colon cancer, strabismus in infants and prethreshold retinopathy, control of glycemia in children with diabetes mellitus, antibullying school programs, skin cancer in organ transplant recipients, squamous cell carcinoma, HIV-related diarrhea in gay men, effect of transcendental meditation in coronary heart disease patients, resistance training in HIV-positive women, and prognosis in multiple sclerosis.

Background: Clinical guidelines exhort clinicians to encourage patients to improve their health behaviours. However, most offer little support on how to have these conversations in practice. Clinicians fear that health behaviour change talk will create interactional difficulties and discomfort for both clinician and patient. This review aims to identify how healthcare professionals can best communicate with patients about health behaviour change (HBC). Methods: We included studies which used conversation analysis or discourse analysis to study recorded interactions between healthcare professionals and patients. We followed an aggregative thematic synthesis approach. This involved line-by-line coding of the results and discussion sections of included studies, and the inductive development and hierarchical grouping of descriptive themes. Top-level themes were organised to reflect their conversational positioning. Results: Of the 17,562 studies identified through systematic searching, ten papers were included. Analysis resulted in 10 top-level descriptive themes grouped into three domains: initiating; carrying out; and closing health behaviour change talk. Of three methods of initiation, two facilitated further discussion, and one was associated with outright resistance. Of two methods of conducting behaviour change talk, one was associated with only minimal patient responses. One way of closing was identified, and patients did not seem to respond to this positively. Results demonstrated a series of specific conversational practices which clinicians use when talking about HBC, and how patients respond to these. Our results largely complemented clinical guidelines, providing further detail on how they can best be delivered in practice. However, one recommended practice - linking a patient's health concerns and their health behaviours - was shown to receive variable responses and to often generate resistance displays. Conclusions: Health behaviour change talk is smoothly initiated, conducted, and terminated by clinicians and this rarely causes interactional difficulty. However, initiating conversations by linking a person's current health concern with their health behaviour can lead to resistance to advice, while other strategies such as capitalising on patient initiated discussions, or collaborating through question-answer sequences, may be well received. [ABSTRACT FROM AUTHOR]