Reproductive skew drives patterns of sexual dimorphism in sponge-dwelling snapping shrimps

Sexual dimorphism is typically a result of strong sexual selection on male traits used in male male competition and subsequent female choice. However, in social species where reproduction is monopolized by one or a few individuals in a group, selection on secondary sexual characteristics may be strong in both sexes. Indeed, sexual dimorphism is reduced in many cooperatively breeding vertebrates and eusocial insects with totipotent workers, presumably because of increased selection on female traits. Here, we examined the relationship between sexual dimorphism and sociality in eight species of Synalpheus snapping shrimps that vary in social structure and degree of reproductive skew. In species where reproduction was shared more equitably, most members of both sexes were physiologically capable of breeding. However, in species where reproduction was monopolized by a single individual, a large proportion of females but not males-were reproductively inactive, suggesting stronger reproductive suppression and conflict among females. Moreover, as skew increased across species, proportional size of the major chela-the primary antagonistic weapon in snapping shrimps increased among females and sexual dimorphism in major chela size declined. Thus, as reproductive skew increases among Synalpheus, female female competition over reproduction appears to increase, resulting in decreased sexual dimorphism in weapon size

Social Control of Reproduction and Breeding Monopolization in the Eusocial Snapping Shrimp Synalpheus elizabethae

Understanding why individuals within altruistic societies forgo reproduction to raise others\u27 offspring has fascinated scientists since Darwin. Although worker polymorphism is thought to have evolved only in sterile workers, worker subcastes appear to be common among social invertebrates and vertebrates. We asked whether sterility accompanies eusociality and morphological differentiation in snapping shrimps (Synalpheus)-the only known marine eusocial group. We show that workers in Synalpheus elizabethae are reproductively totipotent and that female-but not male-gonadal development and mating are mediated by the presence of a queen, apparently without physical aggression. In queenless experimental colonies, a single immature female worker typically became ovigerous, and no female workers matured in colonies with a resident queen. Thus, eusocial shrimp workers retain reproductive totipotency despite signs of morphological specialization. The failure of most female workers to mature is instead facultative and mediate

Backward walking training improves balance in school-aged boys

<p>Abstract</p> <p>Background</p> <p>Falls remain a major cause of childhood morbidity and mortality. It is suggested that backward walking (BW) may offer some benefits especially in balance and motor control ability beyond those experienced through forward walking (FW), and may be a potential intervention for prevention of falls. The objective of this study was to investigate the effects of BW on balance in boys.</p> <p>Methods</p> <p>Sixteen healthy boys (age: 7.19 ± 0.40 y) were randomly assigned to either an experimental or a control group. The experimental group participated in a BW training program (12-week, 2 times weekly, and 25-min each time) but not the control group. Both groups had five dynamic balance assessments with a Biodex Stability System (anterior/posterior, medial/lateral, and overall balance index) before, during and after the training (week- 0, 4, 8, 12, 24). Six control and six experimental boys participated in a study comparing kinematics of lower limbs between FW and BW after the training (week-12).</p> <p>Results</p> <p>The balance of experimental group was better than that of control group after 8 weeks of training (<it>P </it>< 0.01), and was still better than that of control group (<it>P </it>< 0.05), when the BW training program had finished for 12 weeks. The kinematic analysis indicated that there was no difference between control and experimental groups in the kinematics of both FW and BW gaits after the BW training (<it>P </it>> 0.05). Compared to FW, the duration of stance phase of BW tended to be longer, while the swing phase, stride length, walking speed, and moving ranges of the thigh, calf and foot of BW decreased (<it>P </it>< 0.01).</p> <p>Conclusion</p> <p>Backward walking training in school-aged boys can improve balance.</p

Is there an orthographic boost for ambiguous words during their processing?

The present study explores the issue of why ambiguous words are recognized faster than unambiguous ones during word recognition. To this end we contrasted two different hypotheses: the semantic feedback hypothesis (Hino and Lupker in J Exp Psychol Hum Percept Perform 22:1331-1356, 1996. https://doi.org/10.1037/0096-1523.22.6.1331 ), and the hypothesis proposed by Borowsky and Masson (J Exp Psychol Learn Mem Cognit 22:63-85, 1996. https://doi.org/10.1037/0278-7393.22.1.63 ). Although both hypotheses agree that ambiguous words benefit during recognition in that they engage more semantic activation, they disagree as to whether or not this greater semantic activation feeds back to the orthographic level, hence speeding up the orthographic coding of ambiguous words. Participants were presented with ambiguous and unambiguous words in two tasks, a lexical decision task (LDT) and a two-alternative forced-choice task (2AFC). We found differences between ambiguous and unambiguous words in both the LDT and the 2AFC tasks. These results suggest that the orthographic coding of ambiguous words is boosted during word processing. This finding lends support to the semantic feedback hypothesis.This research was funded by the Spanish Ministry of Economy and Competitiveness (PSI2015-63525-P) and by the Research Promotion Program of the Universitat Rovira i Virgili (2016PFR-URV-B2-37). This has also been partially supported by the FCT (Foundation for Science and Technology) through the state budget with Reference IF/00784/2013/CP1158/CT0013. The first author also holds a grant from the Universitat Rovira i Virgili (2015PMF-PIPF-16)

Clinical factors associated with a conservative gait pattern in older male veterans with diabetes

<p>Abstract</p> <p>Background</p> <p>Patients with diabetes and peripheral neuropathy are at higher risk for falls. People with diabetes sometimes adopt a more conservative gait pattern with decreased walking speed, widened base, and increased double support time. The purpose of this study was to use a multivariate approach to describe this conservative gait pattern.</p> <p>Methods</p> <p>Male veterans (mean age = 67 years; SD = 9.8; range 37–86) with diabetes (n = 152) participated in this study from July 2000 to May 2001 at the Veterans Affairs Medical Center, White River Junction, VT. Various demographic, clinical, static mobility, and plantar pressure measures were collected. Conservative gait pattern was defined by visual gait analysis as failure to demonstrate a heel-to-toe gait during the propulsive phase of gait.</p> <p>Results</p> <p>Patients with the conservative gait pattern had lower walking speed and decreased stride length compared to normal gait. (0.68 m/s v. 0.91 m/s, <it>p </it>< 0.001; 1.04 m v. 1.24 m, <it>p </it>< 0.001) Age, monofilament insensitivity, and Romberg's sign were significantly higher; and ankle dorsiflexion was significantly lower in the conservative gait pattern group. In the multivariate analysis, walking speed, age, ankle dorsiflexion, and callus were retained in the final model describing 36% of the variance. With the inclusion of ankle dorsiflexion in the model, monofilament insensitivity was no longer an independent predictor.</p> <p>Conclusion</p> <p>Our multivariate investigation of conservative gait in diabetes patients suggests that walking speed, advanced age, limited ankle dorsiflexion, and callus describe this condition more so than clinical measures of neuropathy.</p

Autism as a disorder of neural information processing: directions for research and targets for therapy

The broad variation in phenotypes and severities within autism spectrum disorders suggests the involvement of multiple predisposing factors, interacting in complex ways with normal developmental courses and gradients. Identification of these factors, and the common developmental path into which theyfeed, is hampered bythe large degrees of convergence from causal factors to altered brain development, and divergence from abnormal brain development into altered cognition and behaviour. Genetic, neurochemical, neuroimaging and behavioural findings on autism, as well as studies of normal development and of genetic syndromes that share symptoms with autism, offer hypotheses as to the nature of causal factors and their possible effects on the structure and dynamics of neural systems. Such alterations in neural properties may in turn perturb activity-dependent development, giving rise to a complex behavioural syndrome many steps removed from the root causes. Animal models based on genetic, neurochemical, neurophysiological, and behavioural manipulations offer the possibility of exploring these developmental processes in detail, as do human studies addressing endophenotypes beyond the diagnosis itself

Eccentric exercise versus Usual-care with older cancer survivors: The impact on muscle and mobility- an exploratory pilot study

<p>Abstract</p> <p>Background</p> <p>Resistance exercise programs with high compliance are needed to counter impaired muscle and mobility in older cancer survivors. To date outcomes have focused on older prostate cancer survivors, though more heterogeneous groups of older survivors are in-need. The purpose of this exploratory pilot study is to examine whether resistance exercise via negative eccentrically-induced work (RENEW) improves muscle and mobility in a diverse sample of older cancer survivors.</p> <p>Methods</p> <p>A total of 40 individuals (25 female, 15 male) with a mean age of 74 (± 6) years who have survived (8.4 ± 8 years) since their cancer diagnosis (breast, prostate, colorectal and lymphoma) were assigned to a RENEW group or a non-exercise Usual-care group. RENEW was performed for 12 weeks and measures of muscle size, strength, power and mobility were made pre and post training.</p> <p>Results</p> <p>RENEW induced increases in quadriceps lean tissue average cross sectional area (Pre: 43.2 ± 10.8 cm²; Post: 44.9 ± 10.9 cm²), knee extension peak strength (Pre: 248.3 ± 10.8 N; Post: 275.4 ± 10.9 N), leg extension muscle power (Pre: 198.2 ± 74.7 W; Post 255.5 ± 87.3 W), six minute walk distance (Pre: 417.2 ± 127.1 m; Post 466.9 ± 125.1 m) and a decrease on the time to safely descend stairs (Pre: 6.8 ± 4.5 s; Post 5.4 ± 2.5 s). A significant (P < 0.05) group x time interaction was noted for the muscle size and mobility improvements.</p> <p>Conclusions</p> <p>This exploration of RENEW in a heterogeneous cohort of older cancer survivors demonstrates increases in muscle size, strength and power along with improved mobility. The efficacy of a high-force, low perceived exertion exercise suggests RENEW may be suited to older individuals who are survivors of cancer.</p> <p>Trial Registration</p> <p>ClinicalTrials.gov Identifier: <a href="http://www.clinicaltrials.gov/ct2/show/NCT00335491">NCT00335491</a></p

Exercise and the Prevention of Oesophageal Cancer (EPOC) study protocol: a randomized controlled trial of exercise versus stretching in males with Barrett's oesophagus

<p>Abstract</p> <p>Background</p> <p>Chronic gastro-oesophageal reflux disease and excessive body fat are considered principal causes of Barrett's oesophagus (a metaplastic change in the cells lining the oesophagus) and its neoplastic progression, oesophageal adenocarcinoma. Metabolic disturbances including altered levels of obesity-related cytokines, chronic inflammation and insulin resistance have also been associated with oesophageal cancer development, especially in males. Physical activity may have the potential to abrogate metabolic disturbances in males with Barrett's oesophagus and elicit beneficial reductions in body fat and gastro-oesophageal reflux symptoms. Thus, exercise may be an effective intervention in reducing oesophageal adenocarcinoma risk. However, to date this hypothesis remains untested.</p> <p>The 'Exercise and the Prevention of Oesophageal Cancer Study' will determine whether 24 weeks of exercise training will lead to alterations in risk factors or biomarkers for oesophageal adenocarcinoma in males with Barrett's oesophagus. Our primary outcomes are serum concentrations of leptin, adiponectin, tumour necrosis factor-alpha, C-reactive protein and interleukin-6 as well as insulin resistance. Body composition, gastro-oesophageal reflux disease symptoms, cardiovascular fitness and muscular strength will also be assessed as secondary outcomes.</p> <p>Methods/Design</p> <p>A randomized controlled trial of 80 overweight or obese, inactive males with Barrett's oesophagus will be conducted in Brisbane, Australia. Participants will be randomized to an intervention arm (60 minutes of moderate-intensity aerobic and resistance training, five days per week) or a control arm (45 minutes of stretching, five days per week) for 24 weeks. Primary and secondary endpoints will be measured at baseline (week 0), midpoint (week 12) and at the end of the intervention (week 24).</p> <p>Discussion</p> <p>Due to the increasing incidence and very high mortality associated with oesophageal adenocarcinoma, interventions effective in preventing the progression of Barrett's oesophagus are urgently needed. We propose that exercise may be successful in reducing oesophageal adenocarcinoma risk. This primary prevention trial will also provide information on whether the protective association between physical activity and cancer is causal.</p> <p>Trial Registration</p> <p>ACTRN12609000401257</p

Human monkeypox virus infection in women and non-binary individuals during the 2022 outbreaks: a global case series.

BACKGROUND: Between May and November, 2022, global outbreaks of human monkeypox virus infection have been reported in more than 78 000 people worldwide, predominantly in men who have sex with men. We describe the epidemiological and clinical characteristics of monkeypox virus infection in cisgender (cis) and transgender (trans) women and non-binary individuals assigned female sex at birth to improve identification and understanding of risk factors. METHODS: International collaborators in geographical locations with high numbers of diagnoses of monkeypox virus infection were approached and invited to contribute data on women and non-binary individuals with confirmed monkeypox virus infection. Contributing centres completed deidentified structured case-report spreadsheets, adapted and developed by participating clinicians, to include variables of interest relevant to women and non-binary individuals assigned female at birth. We describe the epidemiology and clinical course observed in the reported infections. FINDINGS: Collaborators reported data for a total of 136 individuals with monkeypox virus infection who presented between May 11 and Oct 4, 2022, across 15 countries. Overall median age was 34 years (IQR 28-40; range 19-84). The cohort comprised 62 trans women, 69 cis women, and five non-binary individuals (who were, because of small numbers, grouped with cis women to form a category of people assigned female at birth for the purpose of comparison). 121 (89%) of 136 individuals reported sex with men. 37 (27%) of all individuals were living with HIV, with a higher proportion among trans women (31 [50%] of 62) than among cis women and non-binary individuals (six [8%] of 74). Sexual transmission was suspected in 55 (89%) trans women (with the remainder having an unknown route of transmission) and 45 (61%) cis women and non-binary individuals; non-sexual routes of transmission (including household and occupational exposures) were reported only in cis women and non-binary individuals. 25 (34%) of 74 cis women and non-binary individuals submitted to the case series were initially misdiagnosed. Overall, among individuals with available data, rash was described in 124 (93%) of 134 individuals and described as anogenital in 95 (74%) of 129 and as vesiculopustular in 105 (87%) of 121. Median number of lesions was ten (IQR 5-24; range 1-200). Mucosal lesions involving the vagina, anus, or oropharynx or eye occurred in 65 (55%) of 119 individuals with available data. Vaginal and anal sex were associated with lesions at those sites. Monkeypox virus DNA was detected by PCR from vaginal swab samples in all 14 samples tested. 17 (13%) individuals were hospitalised, predominantly for bacterial superinfection of lesions and pain management. 33 (24%) individuals were treated with tecovirimat and six (4%) received post-exposure vaccinations. No deaths were reported. INTERPRETATION: The clinical features of monkeypox in women and non-binary individuals were similar to those described in men, including the presence of anal and genital lesions with prominent mucosal involvement. Anatomically, anogenital lesions were reflective of sexual practices: vulvovaginal lesions predominated in cis women and non-binary individuals and anorectal features predominated in trans women. The prevalence of HIV co-infection in the cohort was high. FUNDING: None