Autogenous and efficient acceleration of energetic ions upstream of Earth's bow shock.

Earth and its magnetosphere are immersed in the supersonic flow of the solar-wind plasma that fills interplanetary space. As the solar wind slows and deflects to flow around Earth, or any other obstacle, a 'bow shock' forms within the flow. Under almost all solar-wind conditions, planetary bow shocks such as Earth's are collisionless, supercritical shocks, meaning that they reflect and accelerate a fraction of the incident solar-wind ions as an energy dissipation mechanism1,2, which results in the formation of a region called the ion foreshock3. In the foreshock, large-scale, transient phenomena can develop, such as 'hot flow anomalies'4-9, which are concentrations of shock-reflected, suprathermal ions that are channelled and accumulated along certain structures in the upstream magnetic field. Hot flow anomalies evolve explosively, often resulting in the formation of new shocks along their upstream edges5,10, and potentially contribute to particle acceleration11-13, but there have hitherto been no observations to constrain this acceleration or to confirm the underlying mechanism. Here we report observations of a hot flow anomaly accelerating solar-wind ions from roughly 1-10 kiloelectronvolts up to almost 1,000 kiloelectronvolts. The acceleration mechanism depends on the mass and charge state of the ions and is consistent with first-order Fermi acceleration14,15. The acceleration that we observe results from only the interaction of Earth's bow shock with the solar wind, but produces a much, much larger number of energetic particles compared to what would typically be produced in the foreshock from acceleration at the bow shock. Such autogenous and efficient acceleration at quasi-parallel bow shocks (the normal direction of which are within about 45 degrees of the interplanetary magnetic field direction) provides a potential solution to Fermi's 'injection problem', which requires an as-yet-unexplained seed population of energetic particles, and implies that foreshock transients may be important in the generation of cosmic rays at astrophysical shocks throughout the cosmos.

Characteristics of Minor Ions and Electrons in Flux Transfer Events Observed by the Magnetospheric Multiscale Mission.

In this study, the ion composition of flux transfer events (FTEs) observed within the magnetosheath proper is examined. These FTEs were observed just upstream of the Earth's postnoon magnetopause by the National Aeronautics and Space Administration (NASA) Magnetospheric Multiscale (MMS) spacecraft constellation. The minor ion characteristics are described using energy spectrograms, flux distributions, and ion moments as the constellation encountered each FTE. In conjunction with electron data and magnetic field observations, such observations provide important contextual information on the formation, topologies, and evolution of FTEs. In particular, minor ions, when combined with the field-aligned streaming of electrons, are reliable indicators of FTE topology. The observations are also placed (i) in context of the solar wind magnetic field configuration, (ii) the connection of the sampled flux tube to the ionosphere, and (iii) the location relative to the modeled reconnection line at the magnetopause. While protons and alpha particles were often depleted within the FTEs relative to the surrounding magnetosheath plasma, the He+ and O+ populations showed clear enhancements either near the center or near the edges of the FTE, and the bulk plasma flow directions are consistent with magnetic reconnection northward of the spacecraft and convection from the dayside toward the flank magnetopause.

[Efficacy and safety of transcranial magnetic stimulation in patients with non-fluent aphasia, following an ischaemic stroke. A controlled, randomised and double-blind clinical trial]. / Eficacia y seguridad de la estimulacion magnetica transcraneal en pacientes con afasia no fluente, posterior a ictus isquemico. Ensayo clinico controlado, aleatorizado y doble ciego.

INTRODUCTION: Non-fluent aphasia is a frequent complication in post-ischemic stroke patients, with repetitive transcranial magnetic stimulation (rTMS) being one of the possible treatment alternatives. AIM: To assess the efficacy and safety of rTMS in patients with non-fluent after-ischemic stroke aphasia. PATIENTS AND METHODS: Double blind, randomized controlled clinical trial in post-stroke patients who were assigned to receive 10 sessions (one daily) of active treatment or placebo of rTMS, without the addition of language therapy. The baseline characteristics were compared initially and the efficacy between the active group versus the placebo group at day 30 was evaluated through a Mann-Whitney U test. RESULTS: 82 patients were included: active group (n = 41) and placebo group (n = 41). At baseline, statistically significant differences were found between the groups in favor of the placebo in the domains of the Boston test of auditory compression (p = 0.024), denomination (p = 0.014) and praxis (p = 0.026), and also occurred on the 30th day in the naming domains (p = 0.037) and reading (p = 0.001). There were 39 adverse reactions: 23 (26.83%) in the active group vs 16 (21.96%) in the placebo group (p = 0.290); the majority corresponded to episodes of mild headache. CONCLUSION: rTMS is a safe therapy, however, given the conditions of this study, we could not demonstrate the efficacy of rTMS versus placebo in patients with non-fluent aphasia with involvement of Broca's area after an ischemic stroke.

TITLE: Eficacia y seguridad de la estimulacion magnetica transcraneal en pacientes con afasia no fluente, posterior a ictus isquemico. Ensayo clinico controlado, aleatorizado y doble ciego.Introduccion. La afasia no fluente es una complicacion frecuente en pacientes postictus isquemico y la estimulacion magnetica transcraneal repetitiva (EMTr) representa una de las posibles alternativas de tratamiento. Objetivo. Evaluar la eficacia y la seguridad de la EMTr en pacientes con afasia no fluente postictus isquemico. Pacientes y metodos. Ensayo clinico controlado doble ciego, aleatorizado, en pacientes postictus isquemico que fueron asignados a recibir 10 sesiones (una diaria) de tratamiento activo o placebo de EMTr, sin adicion de terapia del lenguaje. Las caracteristicas basales fueron comparadas inicialmente, y la eficacia entre el grupo activo frente al grupo placebo el dia 30 se evaluo a traves de una prueba U de Mann-Whitney. Resultados. Se incluyo a 82 pacientes: grupo activo (n = 41) y grupo placebo (n = 41). Se encontraron diferencias basales estadisticamente significativas entre los grupos a favor del placebo en los dominios del test de Boston de compresion auditiva (p = 0,024), denominacion (p = 0,014) y praxis (p = 0,026), e igualmente ocurrio el dia 30 en los dominios de denominacion (p = 0,037) y lectura (p = 0,001). Se presentaron 39 reacciones adversas, 23 en el grupo activo (26,83%) frente a 16 (21,96%) en el grupo placebo (p = 0,290), y la mayoria correspondia a episodios de cefalea leve. Conclusion. La EMTr es una terapia segura, pero dadas las condiciones de este estudio, no pudo demostrarse la eficacia de la EMTr frente al placebo en pacientes con afasia no fluente con afectacion del area de Broca posterior a un ictus isquemico.

[The role played by the autonomic nervous system in the relation between depression and cardiovascular disease]. / Papel del sistema nervioso autónomo en la relación entre depresión y enfermedad cardiovascular.

INTRODUCTION: Findings from several epidemiological studies have revealed that major depression is associated with an increased risk of developing cardiovascular diseases (CVD) and presenting complications and new events in subjects with already-established CVD. The pathophysiological mechanisms responsible for this increased cardiovascular risk in major depression remain unclear. DEVELOPMENT: The aim of this work is to review the literature on the possible pathophysiological mechanisms involved in the relation between major depression and CVD, with special emphasis on the studies dealing with cardiovascular autonomic dysfunction and heart rate variability. Likewise, recent hypotheses concerning the neural mechanisms underlying autonomic dysfunction in subjects with major depression are also discussed. CONCLUSIONS: The evidence that is currently available allows us to hypothesise that there are anomalies in the functioning of the central autonomic neural network in subjects with major depression, and more specifically in the hippocampus, prefrontal cortex and the brain stem nuclei. Such abnormalities, in association with lower central levels of serotonin give rise to a predominance of the sympathetic flow and a loss of cardiac vagal tone. The resulting cardiovascular autonomic dysfunction could be the main cause of the increased cardiovascular risk observed in major depression. In the future, studying the autonomic nervous system may be a useful tool in the development of new therapeutic strategies aimed at reducing cardiovascular morbidity and mortality in subjects with depression.

Coping-with-hearing-loss model for older adults.

We proposed a coping-with-hearing-loss model that explains how hearing loss, psychosocial factors (i.e., attitudes about aging, personal adjustment to hearing loss, and perceived social support), and perceived strategy effectiveness affect the use of adaptive and maladaptive strategies. Adaptive strategies are behaviors that improve communication (i.e., asking others to repeat). Maladaptive strategies are coping behaviors that do not promote communication (i.e., pretending to understand the conversation). Nonaudiological variables were more important than physical hearing loss (as measured by an audiological examination) in predicting coping behaviors for hearing loss. The use of adaptive strategies was predicted by perceived strategy effectiveness. The use of maladaptive strategies was predicted by perceived effectiveness of the strategies to cope with hearing loss in daily life, poor adjustment to hearing loss, and poor social support. The results suggest that psychosocial issues may need to be addressed when older adults have difficulties coping with their hearing loss.

Short-term urea feeding decreases in vitro hatching of bovine blastocysts.

Cows fed high-protein diets may have impaired reproductive performance. Although the pathogenesis has not been completely elucidated, it appears that not only the uterus, but also the follicle and oocyte, are affected by excessive plasma urea nitrogen (PUN) concentrations. Thus, the objective was to determine the effects of short-term urea feeding on the competence of bovine oocytes. Forty crossbred heifers (Bos indicus vs Bos taurus) were allocated to two groups, namely CONTROL (maintenance diet) and UREA (maintenance diet supplemented with 75 g of urea/day), following a cross-over design. Heifers received their respective diets for 6 d (without adaptation). On the sixth day, blood samples were harvested both before and 3 h after feeding, and cumulus oocyte complexes (COCs) were collected by ovum pick-up. Although PUN concentrations were higher in UREA than CONTROL heifers (31.31 mg/dL ± 1.13 vs 22.12 mg/dL ± 0.86; mean ± SEM), neither the number of COCs recovered (8.8 ± 1.0 vs 9.2 ± 0.8, UREA vs CONTROL, respectively) nor their quality (based on morphology) differed significantly between groups. Next, oocytes were fertilized and cultured in vitro to assess developmental rates. There was an absence of significant differences between groups for rates of cleavage (Day 3) or blastocyst formation (Days 6, 7 and 9), but the hatched blastocyst rate on Day 11 after fertilization was lower (P < 0.05) in the UREA than the CONTROL groups (64.3 vs 83.5%). Therefore, we inferred that the effects of urea were only manifest later in development. In conclusion, high PUN concentrations decreased oocyte competence in heifers, reinforcing the hypothesis that poor reproductive performance in cows with high PUN was due, at least in part, to a deleterious effect on oocytes.

Adrenal gland trauma: diagnosis and management.

We describe 14 patients with adrenal injuries from penetrating (ten) or blunt (four) trauma. The severity of their injuries was evidenced by the high incidence of hypovolemic shock (57%), mean Trauma Score (11), mean transfusion requirement (18 Units), number of associated injuries (4.9 per patient), complication rate (57%), and deaths (14%). Twelve patients required surgical exploration; adrenal repair, rather than removal, was possible in seven. Although adrenal insufficiency was suspected in three patients, it was not documented and no patient required corticosteroid replacement.

Gunshot wounds to the male external genitalia.

We report on 23 patients with genital gunshot wounds treated since 1977. Of these 23 patients 16 received 1 shot and 7 received multiple shots. The bullet affected the scrotum in 12 patients, the penis in 4, and the penis and scrotum in the remaining 7. The same missile also compromised the thigh in 15 patients, with major vascular damage in 2. Management was based on serial clinical evaluation and aggressive imaging, related to the missile trajectory. Staging studies were 100% accurate in the patients in whom they were done. Nine patients had damage to the testis (7, 1 bilaterally) and/or spermatic cord (2): 5 required orchiectomy, in 3 the testis was repaired and in 2 the bullet transected the vas, which was ligated with nonabsorbable suture for later repair. Six patients had damage to the corpora, which were repaired. Three patients had urethral rupture (bulbar in 2 and penile in 1): primary repair was feasible in 2 and in 1 (with extensive urethral loss after a shotgun blast) a suprapubic tube was placed for delayed reconstruction. Ten patients had skin penetration only, 5 of whom were managed nonoperatively. There were no major complications or mortality. Also, there were no delayed problems in the nonoperated patients. Erection and normal voiding were reportedly present in all who underwent reconstruction and returned for followup. Early surgical exploration with conservative debridement and primary repair of damaged structures is the preferred treatment for these injuries.

Effect of a lactobacilli preparation on traveler's diarrhea. A randomized, double blind clinical trial.

The effectiveness of prophylactic ingestion of a commercial preparation of lactobacilli (Lactinex) for the prevention or modification of traveler's diarrhea was tested in a randomized double blind clinical trial in 50 volunteer travelers to Mexico from the United States. Twenty-six subjects received the lactobacilli preparation and 24 received placebo. The incidence of diarrhea and its duration during the 4 weeks of observation were quite similar for the two preparations: 35% for lactobacilli-treated subjects and 29% for placebo subjects. Typically, the diarrhea was mild, lasting 2 days. From the observations during this study we conclude that prophylactic ingestion of lactobacilli for 1 week does not reduce the incidence or duration of traveler's diarrhea either during the period of ingestion or during the following 3 weeks.

Papel del sistema nervioso autónomo en la relación entre depresión y enfermedad cardiovascular / The role playedby the autonomic nervous system in the relation between depression and cardiovascular disease

Introducción. Los resultados de varios estudios epidemiológicos han revelado que la depresión mayor está asociada con un riesgo incrementado de desarrollar enfermedades cardiovasculares (ECV) y presentar complicaciones y nuevos eventos en sujetos con ECV establecida. Los mecanismos fisiopatológicos responsables de este aumento del riesgo cardiovascular en la depresión mayor aún no se han esclarecido. Desarrollo. El objetivo del presente trabajo es revisar la literatura sobre los posibles mecanismos fisiopatológicos involucrados en la relación entre la depresión mayor y las ECV, con énfasis en los estudios relacionados con disfunción autonómica cardiovascular y variabilidad de la frecuencia cardíaca. Asimismo, se exponen hipótesis recientes acerca de los mecanismos neurales que subyacen en la disfunción autonómica en sujetos con depresión mayor. Conclusiones. La evidencia disponible permite establecer la hipótesis de que sujetos con depresión mayor presentan anormalidades en el funcionamiento de la red neuronal autonómica central, específicamente en el hipocampo, corteza prefrontal y núcleos del tallo cerebral, que asociadas a la disminución de los niveles centrales de serotonina ocasionan un predominio del flujo simpático y una pérdida del tono vagal cardíaco. La disfunción autonómica cardiovascular resultante podría ser la causa principal del riesgo cardiovascular aumentado observado en la depresión mayor. En el futuro, el estudio del sistema nervioso autónomo puede ser una herramienta útil en el desarrollo de nuevas estrategias terapéuticas enfocadas a disminuir la morbilidad y mortalidad cardiovascular en sujetos deprimidos

Introduction. Findings from several epidemiological studies have revealed that major depression is associated with an increased risk of developing cardiovascular diseases (CVD) and presenting complications and new events in subjects with already-established CVD. The pathophysiological mechanisms responsible for this increased cardiovascular risk in major depression remain unclear. Development. The aim of this work is to review the literature on the possible pathophysiological mechanisms involved in the relation between major depression and CVD, with special emphasis on the studies dealing with cardiovascular autonomic dysfunction and heart rate variability. Likewise, recent hypotheses concerning the neural mechanisms underlying autonomic dysfunction in subjects with major depression are also discussed. Conclusions. The evidence that is currently available allows us to hypothesise that there are anomalies in the functioning of the central autonomic neural network in subjects with major depression, and more specifically in the hippocampus, prefrontal cortex and the brain stem nuclei. Such abnormalities, in association with lower central levels of serotonin give rise to a predominance of the sympathetic flow and a loss of cardiac vagal tone. The resulting cardiovascular autonomic dysfunction could be the main cause of the increased cardiovascular risk observed in major depression. In the future, studying the autonomic nervous system may be a useful tool in the development of new therapeutic strategies aimed at reducing cardiovascular morbidity and mortality in subjects with depression