Effectiveness of predator satiation in masting oaks is negatively affected by conspecific density.

Variation in seed availability shapes plant communities, and is strongly affected by seed predation. In some plant species, temporal variation in seed production is especially high and synchronized over large areas, which is called 'mast seeding'. One selective advantage of this phenomenon is predator satiation which posits that masting helps plants escape seed predation through starvation of predators in lean years, and satiation in mast years. However, even though seed predation can be predicted to have a strong spatial component and depend on plant densities, whether the effectiveness of predator satiation in masting plants changes according to the Janzen-Connell effect has been barely investigated. We studied, over an 8-year period, the seed production, the spatiotemporal patters of weevil seed predation, and the abundance of adult weevils in a holm oak (Quercus ilex) population that consists of trees interspersed at patches covering a continuum of conspecific density. Isolated oaks effectively satiate predators, but this is trumped by increasing conspecific plant density. Lack of predator satiation in trees growing in dense patches was caused by re-distribution of insects among plants that likely attenuated them against food shortage in lean years, and changed the type of weevil functional response from type II in isolated trees to type III in trees growing in dense patches. This study provides the first empirical evaluation of the notion that masting and predator satiation should be more important in populations that start to dominate their communities, and is consistent with the observation that masting is less frequent and less intense in diverse forests.

Movement-Related EEG Oscillations of Contralesional Hemisphere Discloses Compensation Mechanisms of Severely Affected Motor Chronic Stroke Patients.

Conventional rehabilitation strategies for stroke survivors become difficult when voluntary movements are severely disturbed. Combining passive limb mobilization, robotic devices and EEG-based brain-computer interfaces (BCI) systems might improve treatment and clinical follow-up of these patients, but detailed knowledge of neurophysiological mechanisms involved in functional recovery, which might help for tailoring stroke treatment strategies, is lacking. Movement-related EEG changes (EEG event-related desynchronization (ERD) in [Formula: see text] and [Formula: see text] bands, an indicator of motor cortex activation traditionally used for BCI systems), were evaluated in a group of 23 paralyzed chronic stroke patients in two unilateral motor tasks alternating paretic and healthy hands ((i) passive movement, using a hand exoskeleton, and (ii) voluntary movement), and compared to nine healthy subjects. In tasks using unaffected hand, we observed an increase of contralesional hemisphere activation for stroke patients group. Unexpectedly, when using paralyzed hand, motor cortex activation was reduced or absent in severely affected group of patients, while patients with moderate motor deficit showed an activation greater than control group. Cortical activation was reduced or absent in damaged hemisphere of all the patients in both tasks. Significant differences related to severity of motor deficit were found in the time course of [Formula: see text]-[Formula: see text] bands power ratio in EEG of contralesional hemisphere while moving affected hand. These findings suggest the presence of different compensation mechanisms in contralesional hemisphere of stroke patients related to the grade of motor disability, that might turn quantitative EEG during a movement task, obtained from a BCI system controlling a robotic device included in a rehabilitation task, into a valuable tool for monitoring clinical progression, evaluating recovery, and tailoring treatment of stroke patients.

Acute respiratory distress syndrome in a child with human parvovirus B19 infection.

A 6-year-old girl developed shock and multiple organ dysfunction including acute respiratory distress syndrome in association with parvovirus B19 infection. The diagnosis was based on positive antibodies and the detection of parvovirus 19 DNA in serum, bronchial secretions and skin biopsy. It seems likely, but it was not proved, that the parvovirus infection caused acute respiratory distress syndrome.

Unexpected consequences of a drier world: evidence that delay in late summer rains biases the population sex ratio of an insect.

The complexity of animal life histories makes it difficult to predict the consequences of climate change on their populations. In this paper, we show, for the first time, that longer summer drought episodes, such as those predicted for the dry Mediterranean region under climate change, may bias insect population sex ratio. Many Mediterranean organisms, like the weevil Curculio elephas, become active again after summer drought. This insect depends on late summer rainfall to soften the soil and allow adult emergence from their underground refuges. We found that, as in many protandric species, more C. elephas females emerged later in the season. Male emergence timing was on average earlier and also more dependent on the beginning of late summer rainfall. When these rains were delayed, the observed weevil sex ratio was biased towards females. So far, the effects of global warming on animal sex ratios has been reported for temperature-dependent sex determination in reptiles. Our results show that rainfall timing can also bias the sex ratio in an insect, and highlight the need for keeping a phenological perspective to predict the consequences of climate change. We must consider not just the magnitude of the predicted changes in temperature and rainfall but also the effects of their timing.

Transtympanic steroids for Ménière's disease.

OBJECTIVE: To describe the long-term efficacy of transtympanic steroids (TTS) using methyl-prednisolone in the treatment of Ménière's disease (MD). DESIGN: Descriptive prospective study. MAIN OUTCOME MEASURES: Pure-tone average (PTA) corresponding to the conversational frequencies on the audiogram (0.5, 1, 2, and 3 kHz), visual analog scale on tinnitus annoyance, and number of vertigo spells 24 months after treatment. RESULTS: Thirty-four MD patients referred to a tertiary center were treated with TTS. All patients were diagnosed as probable or definitive MD (following American Academy of Otolaryngology-Head and Neck Surgery 1995 criteria) and treated by TTS (3 consecutive doses). Data from 32 patients were achieved after 12 months. Forty-eight percent of the patients reduced the PTA in 10 or more decibels, average improvement was 8.6 dB compared with initial PTA (p = 0.004). Tinnitus relief was achieved by 81.5% of the patients. Number of vertigo spells was reduced from 4.3 to 0.3 after 12 months (p = 0.002); 81% of the patients were free of vertigo spells, and 92.6% had 1 or less spells of vertigo. Data from 29 patients were achieved after 24 months. A reduction of PTA in 10 or more decibels was shown by the 33.3% of the sample, and PTA improved in 3.3 dB compared with initial PTA (nonsignificant). Tinnitus relief was achieved in 78% of the patients. Number of vertigo spells was reduced from 4.3 to 0.5 (p = 0.033). Seventy-eight percent of the cases were free of vertigo, and 96% had none or 1 spell. Because of an increase in any of the symptoms, 12 patients (35.2%) required retreatment with 1 or 2 series of TTS (1-3 doses) along the 2-year period. Two patients of the sample (6.25%) required transtympanic gentamicin for vertigo control due to lack of benefit with TTS (14 and 18 mo since TTS). CONCLUSION: Transtympanic steroids in this cohort were associated with good preservation of hearing. Tinnitus control is achieved in more than 70% of the patients, and number of vertigo spells can be dramatically reduced in more than 90% of the patients after a 24-month follow-up.

Tinnitus retraining therapy: prognosis factors.

INTRODUCTION: Tinnitus retraining therapy (TRT) is, nowadays, one of the most extended treatments for tinnitus control. The goal is the habituation to a nonsignificative signal, that is, tinnitus, first, eliminating its reaction and, second, minimizing its perception. PURPOSE: The objective of this study is to identify the factors that could improve or reduce the efficacy of TRT. MATERIALS AND METHODS: A prospective nonrandomized clinical assay (n = 137) was conducted. Three parameters were considered for tinnitus evaluation at 1-year follow-up: patient self-evaluation, visual analogue scale for intensity, and Tinnitus Handicap Inventory. RESULTS: Tinnitus retraining therapy group improved at 1-year follow-up, considering the 3 parameters. The most important factor of failure to TRT efficacy has been the refuse to instrumentation when it was required, according to TRT recommendations. Tinnitus Handicap Inventory score in this group did not show any improvement (P = .009). Highest scores of tinnitus intensity (visual analogue scale) and handicap (Tinnitus Handicap Inventory) before treatment as well as the most disabled diagnosis (sudden deafness and Meniere's disease) had better response to TRT. Jastreboff's treatment categories, longer presence of tinnitus, existence of hyperacusis or hearing loss, type of prosthesis used, duration of the treatment, and index of assistance to our follow-up program were not related to the effectiveness of TRT. CONCLUSIONS: Tinnitus retraining therapy has demonstrated to be an effective treatment of tinnitus. More severe tinnitus are susceptible to get better response with this approach. Instrumentation, when recommended, is mandatory to obtain a higher relief of this symptom (EMB rating: B-2).

Experimentally increased testosterone affects social rank and primary sex ratio in the spotless starling.

It has been suggested that the amount of maternal testosterone allocated into the eggs might be implicated in the process of sex determination. However, recent findings on the effect that female social rank has on the level of egg testosterone suggest that reported associations between male-biased sex ratios and yolk testosterone may represent an indirect hormonal effect mediated by the interdependence among maternal hormones, female social rank, and sex ratio. Here, we report the results of a field experiment in which we manipulated the circulating levels of testosterone in female spotless starlings (Sturnus unicolor) before egg formation. Focal females were controlled in subsequent years to explore possible delayed effects of hormone manipulation on primary sex ratio and social status that could persist because of permanent hormonal change or through hormone-dominance interactions. The results indicate that testosterone-implanted females (T-females) produced significantly more sons than control females (C-females) in the year in which they were manipulated. These differences in offspring sex ratio between T- and C-females persisted in the next 3 years, although no additional hormone treatments were given. These results were not mediated by an eventual effect of testosterone treatment on the quality of the females' mates. A similar proportion of T- and C-females acquired a nest box and bred either in the manipulation year or in Year 1 after manipulation, but T-females tended to be more successful in acquiring a nest box than C-females in Years 2 and 3 after manipulation. These results suggest that added testosterone had a direct role on the acquisition and maintenance of high social rank. Delayed effects of testosterone on primary sex ratio might have been caused by altered endogenous production of T-females. Alternatively, the maintenance of sex ratio differences between T- and C-females long after having being implanted might be attributed to the positive effect that enhanced social rank of T-females has on their circulating testosterone levels.