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Reference conditions are difficult to find in the Anthropocene but essential for effective biodiversity conservation. Aquatic ecosystems in the Andes‐Amazon transition zone of Colombia are now at high risk due to expanded human activities after peace agreements in 2016 ended armed conflict because lands formerly controlled by FARC and other armed groups are now prone to agricultural and urban expansion. Particularly, expanding human land use may reduce fish diversity across the altitudinal gradient, especially in the premontane streams (i.e., <500 m a.s.l.) because lands are more amenable to human use than at greater altitudes. We evaluated fish α‐diversity (measured as species richness, total abundance, and effective species number) and β‐diversity (spatial and temporal) in 12 sites over 8 years bracketing the end of armed conflict. All α‐diversity and β‐diversity analyses were evaluated relative to categorical altitude (< or >500 m) and continuous altitude. Strong differences in fish community structure among sites occurred as a function of altitude. Fish communities exhibit altitudinal biodiversity gradients that are consistent in space and time, and that need to be accounted for conservation and management considerations. Our results provide a reference to identify short‐ and long‐term changes due to impending human land use at a critical moment for the conservation of tropical fish diversity. Similar studies in other areas of the upper Amazon Basin are needed to evaluate effects of subsequent human activities on diversity patterns and our study area to compare to reference conditions reported here. [ABSTRACT FROM AUTHOR]

Nonnative species mitigation is important to conserve Florida's native wildlife, especially with nonnative reptiles such as Nile Monitors (Varanus niloticus). Nile Monitors are habitat and dietary generalists in their native (Africa) and nonnative (Florida) ranges and were introduced to Florida in the early 1990s through the pet trade. Nile Monitors have since become established in three coastal counties in southern Florida. Confirmed sightings extend beyond established Nile Monitor populations into parts of central and northern Florida, but it is unclear whether spread is likely to these areas or even into surrounding states. Mitigation strategies to locate, remove, and proactively prevent introduction and spread of nonnative species include species distribution models (SDMs). Two Nile Monitor SDMs currently exist but are not at an appropriate scale to inform regional management practices and include various methods that do not meet current model quality standards. Nile Monitor SDMs here represent high-quality, region-scale predictions at a 1 km2 resolution fitted with ensembles of algorithms, 14 predictors (including environmental and anthropogenic variables), and occurrence data from both the native and nonnative ranges. Final SDM predictions indicate little habitat suitability and low probability of spread beyond the central region of Florida, contradictory to existing Nile Monitor SDMs. Pathways of suitable habitat exist from established populations into other central and southern parts of Florida along coastlines and suggest possible anthropophilic habitat preferences that will require further telemetric behavioral studies to validate. [ABSTRACT FROM AUTHOR]

Explaining the mechanisms underlying spatial and temporal variation in community composition is a major challenge. Nevertheless, the processes controlling temporal variation at a site (i.e. temporal β‐diversity, including its turnover and nestedness components) are less understood than those affecting variation among sites (i.e. spatial β‐diversity). Short‐term temporal turnover (e.g. throughout an annual cycle) is expected to correlate positively with seasonal environmental variability and landscape connectivity, but also species pool size (γ‐diversity). We use the megadiverse Amazonian freshwater ichthyofauna as a model to ask whether seasonality and landscape connectivity drive variation in temporal species turnover among geomorphological habitat types, while accounting for between‐habitat variation in γ‐diversity. We collected 11 397 fish representing 260 species during a year‐long sampling program from an area containing the lowland Amazon's four major geomorphological habitat types: rivers, floodplains, terra firme streams, and shield streams. River‐floodplain systems exhibit strong but predictable seasonality (via a high‐amplitude annual flood pulse), high connectivity, and high species richness with many rare species. Terra firme and shield streams exhibit low seasonality, low connectivity, and low species richness with proportionally fewer rare species. Based on these parameters we predicted that river‐floodplain systems should have higher temporal turnover than stream systems. Using a null model approach combined with β‐deviation calculations, we confirmed that rivers and floodplains do exhibit higher turnover (but not nestedness) than terra firme and shield streams, even when controlling for the potentially confounding effect of higher species richness in river‐floodplain systems. All habitats exhibit low temporal nestedness, indicating that short‐term changes in community composition result primarily from temporal species turnover. Our results provide a timely reminder that efforts to conserve the Amazon's threatened aquatic biodiversity should account for the distinct temporal dynamics of habitat types and variation in hydrological seasonality. [ABSTRACT FROM AUTHOR]

High intensity interval training (HIIT) has been shown to consistently elicit rapid and significant adaptations in a number of physiological systems, across many different healthy and clinical populations. In addition, there is increasing interest in how some acute, yet transient responses to high intensity exercise potentially reduce the risks of particular diseases. Recent work has shown that discrete, brief bouts of high intensity exercise (termed 'exercise snacks') can improve glucose control and vascular health and thus counter the negative cardiometabolic consequences of prolonged, uninterrupted periods of inactivity. In this brief review, we advance the case, using evidence available from pre‐clinical studies in the exercise oncology literature, that brief, frequently completed bouts of high intensity exercise embedded within an individual's overall daily and weekly physical activity schedule, may transiently impact the tumour microenvironment and improve the health outcomes for those who have been diagnosed and treated for cancer. [ABSTRACT FROM AUTHOR]

Combined effects of disturbance and productivity on ecological diversity have been considered for decades as the dynamic equilibrium model (DEM) but are rarely tested together. Instead, most studies focus on either the intermediate disturbance hypothesis or sometimes the intermediate productivity hypothesis. In addition, most analyses of disturbance and productivity effects have relied on nonexperimental patterns, limited sample sizes, inaccurate proxies for productivity, and/or simple measures of diversity. The DEM operates at regional and local scales; here, we conducted a year‐long experiment at local scales using submersed aquatic vegetation in outdoor mesocosms with a factorial combination of physical disturbance and productivity treatments. We evaluated diversity in several ways, directly measured productivity, and compared alternative hypotheses using model selection. The DEM was supported for effective diversity; both productivity and disturbance effects were clear, though productivity effects were stronger. Other diversity measures for the simple communities in the mesocosms did not clearly reflect treatments. The DEM is a valuable general framework for understanding disturbance and productivity effects on ecological systems and is made more general by minor conceptual adjustments here. [ABSTRACT FROM AUTHOR]

Mental fatigue has been shown to negatively influence physical, technical and tactical aspects of sporting performance. However, mental fatigue is not routinely monitored or managed in elite sport and it is not clear whether mental fatigue occurs and/or changes across the varied contextual demands experienced by elite athletes in training, preparation and competition. This study explored self-report measures of mental fatigue across eight training camps and six competition periods (two benchmark tournaments and four international test series) with international netballers (n = 22, 25.9 ± 2.7 years) during the 2018–2019 representative period. Mental fatigue was higher during training camps (p < 0.001; 3.20 [3.12, 3.27]) and preparation camps (p < 0.05; 3.27 [3.19, 3.34]) compared to the competition periods (3.49 [3.44, 3.55]). Significant within-group differences were also identified between individual preparation camps and competition subsets. Higher mental fatigue was reported during the preparation camp for international test series 2 comparative to the preparation camp for benchmark tournament 1 (p = 0.047). For individual competitions; greater mental fatigue was found during the international test series 3 competition in comparison to both the benchmark tournament 1 (p <0.001) and international test series 1 (p = 0.020) competition periods. International representative netballers experience differing levels of mental fatigue across training and preparation camps and competition periods. Practitioners should be aware that athletes report instances of elevated mental fatigue across camps, and competition. Mental fatigue is not limited to competition and thus is recommended to be monitored during periods of training and preparation for competition. International representative netballers experience differing levels of mental fatigue across camp and competition environments. Mental fatigue was higher during training camps and preparation camps compared to the competition periods. Mental fatigue is not limited to competition so is recommended to be monitored during periods of training and preparation for competition. [ABSTRACT FROM AUTHOR]

Wildlife‐vehicle collisions (WVCs) are a major source of wildlife mortality and should affect regional wildlife diversity and abundance, yet most WVC studies are locally scaled. Here, we evaluated biogeographic diversity (i.e., species richness, effective diversity) and abundance of WVCs at state parks across the Florida peninsula to answer two questions aimed to help inform wildlife conservation efforts: which parks have greatest WVC diversity, and why? We processed and compiled 9,254 WVC survey records collected by Florida State Parks personnel at 42 parks during a decade (2005–2015). Data for birds (138 species), mammals (35 species), reptiles (64 species), and all taxa combined were analyzed for patterns among parks (for the first question) and for biogeographic, climatic, ecoregion, and anthropogenic predictors of those patterns (for the second). Predictors represented nonexclusive alternative a priori hypotheses and were evaluated by model comparison. Parks differed widely in WVC diversity and abundance; we identify "hot spot" parks where management may most effectively reduce WVCs. Biogeographic and anthropogenic hypotheses were supported, but climatic and ecoregion hypotheses were not. Models for overall diversity fit data better (R2s > 0.50) than did models for specific taxa (e.g., birds). Larger parks closer to Florida's highly populated Atlantic Coast and with greater park attendance and perhaps faster speeds on adjacent roads have more WVC diversity and numbers. Of these predictors, attendance and speed limits are manageable. Traffic management in and near‐identified "hot spot" parks in Florida can most effectively reduce WVC effects on wildlife populations and diversity amidst a growing human population. [ABSTRACT FROM AUTHOR]

Aim: Ecological theory is not often applied to human appropriation of net primary production (HANPP), which estimates reduction of natural net primary production (NPP) due to harvest and land use. Here we use predator–prey theory to evaluate HANPP as "predation". Macroecology and adaptive life history strategies also help evaluate relationships among global terrestrial HANPP, NPP, and plant biomass (B). Location: Lands worldwide. Time period: 2000. Major taxa studied: Terrestrial plants. Methods: HANPP and potential NPP allometric scaling were estimated for terrestrial ecoregions (N = 819, for 86% of global land surface area) in the year 2000. HANPP and NPP scaling were compared and projected to current and year 2050 conditions. NPP scaling for potential versus actual conditions were also compared, as were biomass turnover rates (T; per year). Results: Global HANPP scales predictably with B; consistent with predator–prey theory, HANPP scaling is not clearly satiated at greater B. NPP scaling supports adaptive life history strategies theory. HANPP scaling is c. 16% of NPP scaling; a conservative estimate compared to a grid‐based 22%. HANPP scaling could become 25–35% of potential NPP scaling by 2050 due to population growth, or be constrained to 20–26% of potential NPP scaling if resource use efficiency improves. However, B is more sensitive than NPP to human effects, and human population size and HANPP now dominate as predictors of T. Main conclusions: Three ecological theories converged here to broadly support prior empirical estimates and enable novel insights. B and T are more sensitive to global human impacts than is NPP and should be priorities for carbon budgets and conservation. Human population growth and resource use efficiency strongly affect terrestrial plant HANPP, B and T, and thus global carbon budget. Both human "top‐down" effects (evaluated here) and "bottom‐up" drivers (e.g., climate, nutrients, CO2) need to be incorporated into global carbon models. [ABSTRACT FROM AUTHOR]

Regressions and meta-regressions are widely used to estimate patterns and effect sizes in various disciplines. However, many biological and medical analyses use relatively low sample size (N), contributing to concerns on reproducibility. What is the minimum N to identify the most plausible data pattern using regressions? Statistical power analysis is often used to answer that question, but it has its own problems and logically should follow model selection to first identify the most plausible model. Here we make null, simple linear and quadratic data with different variances and effect sizes. We then sample and use information theoretic model selection to evaluate minimum N for regression models. We also evaluate the use of coefficient of determination (R2) for this purpose; it is widely used but not recommended. With very low variance, both false positives and false negatives occurred at N < 8, but data shape was always clearly identified at N ≥ 8. With high variance, accurate inference was stable at N ≥ 25. Those outcomes were consistent at different effect sizes. Akaike Information Criterion weights (AICc wi) were essential to clearly identify patterns (e.g., simple linear vs. null); R2 or adjusted R2 values were not useful. We conclude that a minimum N = 8 is informative given very little variance, but minimum N ≥ 25 is required for more variance. Alternative models are better compared using information theory indices such as AIC but not R2 or adjusted R2. Insufficient N and R2-based model selection apparently contribute to confusion and low reproducibility in various disciplines. To avoid those problems, we recommend that research based on regressions or meta-regressions use N ≥ 25. [ABSTRACT FROM AUTHOR]

The aim of the current study was to investigate the effect of 180 mg of pseudoephedrine (PSE) on cycling time-trial (TT) performance. Six well-trained male cyclists and triathletes (age 33 ± 2 yr, mass 81 ± 8 kg, height 182.0 ± 6.7 cm, VO2max 56.8 ± 6.8 ml · kg-1 · min-1; M ± SD) underwent 2 performance trials in which they completed a 25-min variable-intensity (50-90% maximal aerobic power) warm-up, followed by a cycling TT in which they completed a fixed amount of work (7 kJ/kg body mass) in the shortest possible time. Sixty minutes before the start of exercise, they orally ingested 180 mg of PSE or a cornstarch placebo (PLA) in a randomized, crossover, double-blind manner. Venous blood was sampled immediately pre- and postexercise for the analysis of pH plus lactate, glucose, and norepinephrine (NE). PSE improved cycling TT performance by 5.1% (95% CI 0-10%) compared with PLA (28:58.9 ± 4:26.5 and 30:31.7 ± 4:36.7 min, respectively). There was a significant Treatment × Time interaction (p = .04) for NE, with NE increasing during the PSE trial only. Similarly, blood glucose also showed a trend (p = .06) for increased levels postexercise in the PSE trial. The ingestion of 180 mg of PSE 60 min before the onset of high-intensity exercise improved cycling TT performance in well-trained athletes. It is possible that changes in metabolism or an increase in central nervous system stimulation is responsible for the observed ergogenic effect of PSE. [ABSTRACT FROM AUTHOR]

Physical profile data from elite, sub-elite, regional, under 21s (U21), under 19s (U19) and under 17s (U17) (n = 845) players from a state netball association in Australia were analysed. Within season changes were examined for the elite and sub-elite players. Longitudinal changes were examined for the elite across four consecutive netball seasons. Elite were significantly older (24.3 ± 3.4years), taller (182.4 ± 7.2cm) and heavier (73.42 ± 6.95kg) than other playing levels (p < 0.001, ES 0.49–3.26) and had higher vertical jump (VJ) data compared to all groups (p < 0.001, ES 0.47–0.93). U17's were significantly faster than elite, sub-elite and U19 players over 5m (p < 0.05, ES 0.36–0.58) while elite were faster over 20m compared to all groups (p < 0.01, ES 0.45–0.72). Elite achieved a greater distance (1350.8m; p < 0.05, ES 0.32–0.50) in the Yo-YoIRT1 compared to the sub-elite, regional, U19 and U17. VJ height significantly increased from the 2014 (51.6 ± 4.8cm) to the 2017 season (59.6 ± 6.3cm) for the elite players (p < 0.01, ES 1.18). Yo-YoIRT1 test scores increased significantly between the pre-season and in-season phases (p < 0.05, ES 0.17). [ABSTRACT FROM AUTHOR]

This study examined the changes in running performance, maximal blood lactate concentrations and running kinematics between 85%BM anti-gravity (AG) running and normal over-ground (OG) running over an 8-week training period. Fifteen elite male developmental cricketers were assigned to either the AG or over-ground (CON) running group. The AG group (n = 7) ran twice a week on an AG treadmill and once per week over-ground. The CON group (n = 8) completed all sessions OG on grass. Both AG and OG training resulted in similar improvements in time trial and shuttle run performance. Maximal running performance showed moderate differences between the groups, however the AG condition resulted in less improvement. Large differences in maximal blood lactate concentrations existed with OG running resulting in greater improvements in blood lactate concentrations measured during maximal running. Moderate increases in stride length paired with moderate decreases in stride rate also resulted from AG training. The use of AG training to supplement regular OG training for performance should be used cautiously, as extended use over long periods of time could lead to altered stride mechanics and reduced blood lactate. [ABSTRACT FROM AUTHOR]

The aim of this brief study was to investigate the effects of repeated jump testing on performance over 2 consecutive days while considering the possibility of diurnal changes. Fourteenmale subjects and 14 recreationally active female subjects completed countermovement jump (CMJ) and squat jump (SJ) testing on 5 occasions (baseline [0,800], 5 minutes [0,820], 8 hours [1,600], 24 hours [0,800], and 32 hours [1,600]) over 32 hours. An additional rested baseline test was conducted on a separate day in the afternoon (1,600) to compare jump performance between morning and afternoon baseline values. Excluding small decreases in CMJ height at 24 hours (p50.292, Cliff's delta520.225) in male subjects and similar decreases in CMJ height at 5 minutes (p 5 0.034, Cliff's delta 5 20.245) in addition to SJ height:contraction time at 32 hours (p 5 0.126, Cliff's delta5 0.153) in female subjects, findings generally showed no changes in jump performance over multiple assessments. Squat jumpmetrics may have showed small improvements betweenmorning and afternoon baseline values inmale subjects (SJ height:contraction time [p50.030, Cliff's delta50.225]) and female subjects (SJ height [p50.013, Cliff's delta50.173] and SJ height:contraction time [p50.091, Cliff's delta50.163)]. As jump performance was largely unaffected by repeated jump testing, the present findings support the use ofmonitoring practices and research designs that require multiple jump assessments within acute periods (;32 hours). [ABSTRACT FROM AUTHOR]

The aim of this study was to examine responses at 3 and 27 hours after low-load jump squat (LL) and maximal isometric half-squat (ISO) priming stimuli. Fifteen resistance-trained males performed LL (4 3 3 at 20% 1 repetition maximum [1RM]), ISO (4 3 3 seconds), and control (CON) activities (standardized warm-up) in a randomized and counterbalanced order. Countermovement jump (CMJ) and isometric midthigh pull tests were conducted to assess performance changes after priming and CON activities. No clear changes in CMJ measures were found after priming activities compared with CON. However, small effect size improvements were found after priming stimuli completed on the same day. A 2.9% decrease in concentric phase duration (CI 5 0.3-5.9, p 5 0.333, Cliff's delta520.156) and a 9.1% increase in RSImod (CI 50.2-12.3, p50.151, Cliff's delta520.218) occurred at 3 hours after LL compared with CON. Braking phase duration (CI 5 0.8-10.6, p 5 0.333, Cliff's delta520.213) was 2.9% shorter at 3 hours after ISO compared with CON. No clear changes in isometric peak force occurred after priming activities compared with CON. Additionally, questionnaires were completed to assess perceptual state and perceived effectiveness of the priming stimulus to influence performance. An increase in the "effect of activity" was perceived at 3 hours after LL and ISO (p 5 0.013-0.044, Cliff's delta 5 0.578-0.6) and at 27 hours after ISO (p 5 0.99, Cliff's delta 5 0.173) compared with CON. An increase in "muscular heaviness" was also reported at 3 hours after ISO compared with CON (p 5 0.199, Cliff's delta 5 0.320). The collective findings suggest limited benefits over the day after LL and ISO priming stimuli. However, as there was substantial variation in individual responses, the relative nature of priming responses should be considered when prescribing similar strategies in practical environments. [ABSTRACT FROM AUTHOR]

Harrison, PW, Kelly, VG, Jenkins, DG, McGuigan, MR, Holmberg, PM, and James, LP. Does moderate-load priming activity influence maximal upper-body performance and perceptual state?. J Strength Cond Res 37(11): e581-e587, 2023--The results of previous research indicate that resistance exercise "priming" may improve strength-power measures within 48 hours after their completion. Although researchers have primarily examined performance responses after lower-body priming stimuli, investigations examining the effects of upper-body resistance priming exercises are presently limited. Therefore, the aim of this study was to examine upper-body pushing and pulling performance in addition to perceptual responses 3 and 27 hours after moderate-load (ML) upper-body resistance priming exercise. Fourteen resistance-trained men were assigned to complete ML priming (4 3 3 bench press and bench pull at 65% 1RM [repetition maximum]) and control (rest) protocols in a randomized and counterbalanced order. Peak velocity during the bench throw and bench pull tests involving different loads (25, 50, and 75% 1RM) showed no practical change at 3 and 27 hours after the priming session (p 5 0.216-0.99, Cliff's d520.041 to 0.225). Small effect size increases in perceptual measures ("physical feeling," "physical performance," "aggression" [p 5 0.400-0.553, Cliff's d 5 0.183-0.201], and "muscular heaviness" [p 5 0.178, Cliff's d 5 0.231]) were found at 3 hours postpriming. A moderate practical increase was observed in perceived "physical feeling" compared with control (p 5 0.385, Cliff's d 5 0.349) in addition to small effect size increases in perceived "physical performance" and "aggression" (Cliff's d50.243-0.290) at 27 hours after priming activities. These results indicate that upper-body strength-power changes within 27 hours after ML upper-body resistance exercise priming are not practically meaningful. [ABSTRACT FROM AUTHOR]

Allometric scaling of net primary production ( NPP) with plant biomass (B) is important to ecological carbon dynamics and energetics. Metabolic theory predicts a nonlinear power law for NPP scaling, based on fractal vascular systems, resulting in a linear model when using log NPP/log B axes that are standard in allometry. Alternatively, two other hypotheses predict nonlinear models for log-transformed data, with potential tipping points. Size-based competition may cause a quadratic curve as larger plants limit NPP by smaller plants. More inclusively, the plant adaptive strategies hypothesis predicts a sigmoidal curve to represent those same competitive effects, plus stress and ruderal adaptations that maintain relatively low NPP in habitats that are abiotically limiting or disturbed., We evaluated all three hypotheses for terrestrial vascular plants, using information theoretic model selection based on the Akaike Information Criterion ( AICc). Published data ( N = 709) were organised in subsets according to reported organisational level and plant growth form. Alternative curves were compared for a general model (using all data) and per subset. Potential tipping points were estimated using segmented regression., The plant adaptive strategies hypothesis was supported in general ( AICc weight = 1·00) and via internal consistency for five of six subsets (86% of data). Competition was supported as affecting NPP at greater B, where quadratic and sigmoidal models often coincided. Only non-woody assemblages most plausibly fit a power law model, perhaps related to sparse data at lowest B., Synthesis. Adaptive strategies and corresponding environmental conditions appear to constrain terrestrial net primary production scaling relative to metabolic theory's ideal. Moreover, tipping points in general nonlinear net primary production scaling (at c. 38 and 360 g m−2 B) indicate thresholds for rapid changes in net primary production given changing B that occurs via changing climate, human appropriation and land use. [ABSTRACT FROM AUTHOR]

Purpose: Oral contraceptive (OC) use reduces peak aerobic capacity (...O2peak); however, whether it also influences adaptations to training has yet to be determined. This study aimed to examine the influence of OC use on peak performance (peak power output [PPO]) and physiological adaptations (...O2peak and peak cardiac output [...peak]) after sprint interval training (SIT) in recreationally active women. Methods: Women taking an OC (n = 25) or experiencing natural regular menstrual cycles (MC; n = 16) completed an incremental exercise test to assess ...O2peak, PPO, and ...peak before, immediately after, and 4 wk after 12 sessions of SIT. The SIT consisted ten 1-min efforts at 100% to 120% PPO in a 1:2 work-rest ratio. Results: Though ...O2peak increased in both groups after SIT (both P < 0.001), the MC group showed greater improvement (OC, +8.5%; MC, +13.0%; P = 0.010). Similarly, ...peak increased in both groups, with greater improvement in the MC group (OC, +4.0%; MC, +16.1%; P = 0.013). PPO increased in both groups (OC, +13.1%; MC, +13.8%; NS). All parameters decreased 4 wk after SIT cessation, but remained elevated from pretraining levels; the OC group showed more sustained training effects in ...O2peak (OC, -4.0%; MC, -7.7%; P = 0.010). Conclusion: SIT improved peak exercise responses in recreationally active women. However, OC use dampened ...O2peak and ...peak adaptation. A follow-up period indicated that OC users had spared ...O2peak adaptations, suggesting that OC use may influence the time course of physiological training adaptations. Therefore, OC use should be verified, controlled for, and considered when interpreting physiological adaptations to exercise training in women. [ABSTRACT FROM AUTHOR]

As land is converted to agriculture (e.g., pastures), natural vegetation is repeatedly disturbed, creating various levels of habitat alteration in which flowering plants and pollinators (e.g., bees) interact. Community structure of flowering plants, bees, and flower-bee interactions may each respond to disturbance, but potentially in different ways or magnitudes. We studied flowering plants, bees, and their interactions across four mechanical disturbance levels in and near Archbold Biological Station, Florida (USA) for one year, using repeated sampling with standard techniques in replicated plots. Data were analyzed for community structure, flower-bee interactions and bipartite network structure. Over 7500 flowering plants (81 species) and almost 5000 bees (48 species) were sampled, representing > 80% of estimated species richness. Disturbance altered available flower diversity and both shifted and simplified compositions of floral and bee communities. Importantly, the number of foraging bee species did not decrease with disturbance but fewer bee species interacted with flowers given greater disturbance, indicating that disturbance reduced successful foraging. Interaction networks became simpler with disturbance, and the non-native European honey bee ( Apis mellifera ) became more dominant as disturbance intensity increased. Flower-bee interactions were most sensitive to disturbance. For some native bees, anthropogenic disturbance may contribute to ecological trap conditions and drive long-term diversity patterns. Attention to interaction networks will help land managers identify plant species to conserve and restore flowering plants that are vital to native pollinator communities. [ABSTRACT FROM AUTHOR]

Purpose: The objective of this study is to compare the integrated muscle protein synthesis (MPS) rates of masters and younger triathletes over three consecutive days of intense endurance training. Recovery of cycling performance, after muscle-damaging running, was also compared between groups. Methods: Five masters (age, 53 ± yr; ...O2max, 55.7 ± 6.9 mL⋅kg-1⋅min-1) and six younger (age, 27 ± 2 yr; ...O2max, 62.3 ± 1.5 kg-1⋅min-1) trained triathletes volunteered for the study. Baseline skeletal muscle and saliva were initially sampled, after which a 150-mL bolus of deuterium oxide (70%) was consumed. Participants then completed a 30-min downhill run; three 20-km cycling time trials (TT) were completed 10,24, and 48 h after the run. Saliva was collected each morning, and skeletal muscle was again sampled 72 h after the run; both were used for MPS analysis. Diet was controlled throughout the study. Results: Over 3 d, masters triathletes showed a significantly lower myofibrillar fractional synthetic rate (1.49% ± 0.12%-d-1) compared with the younger (1.70% ± 0.09%-d-1) triathletes (P = 0.009, d = 1.98). There was also a trend for masters triathletes to produce a slower cycle TT (-3.0%, d = 0.46) than younger triathletes (-1.4%, d = 0.29) at 10 h postrun in comparison with the baseline performance. The between-group comparison of change was moderate (d = 0.51), suggesting slower acute recovery among masters triathletes. Conclusions: The present data show lower MPS rates in well-trained masters triathletes over 3 d of training, and this likely contributes to poorer muscle protein repair and remodeling. Furthermore, acute recovery of cycle TT performance tended to be poorer in the masters triathletes. [ABSTRACT FROM AUTHOR]

• Humans impact terrestrial ecosystems through our actions, often permanently. • We find equations to predict a major human impact – our removal of plants. • Humans act like other predators to use more plants where more exist. • But climate, human population, economy, and technology also affect that pattern. • Strong predictions for where impacts occur helps to better manage those impacts. Human impacts on natural systems are often analysed using a statistical model based on the 50-year old IPAT concept, where impact (I) is a function of population (P), affluence (A), and technology (T). Varied results have accrued, but problems remain: ecological predictors are not part of the anthropocentric IPAT concept or statistical model; vastly different countries are often treated as statistical replicates; alternative hypotheses are rarely compared; and most studies evaluated only CO 2 emissions as impacts. Here we compare alternative mixed-effect models to predict human appropriation of net primary production (HANPP) as an indicator of global human impacts at relatively fine scale (5 arc-min grid). Predictors represent anthropocentric (P, A and T) and/or ecological (plant biomass and climate) effects, with countries (N = 168) and/or anthropogenic biomes (anthromes; N = 19) as random effects. The most efficient models predict location and amount of HANPP well (R2 = 0.91 and 0.63, respectively) and use all predictors listed above. In both cases, ecological predictors and population have greatest effects on HANPP, consistent with a general, ecological predator–prey relationship modified by socio-ecological conditions. Global human impacts on terrestrial ecosystems (measured as HANPP) depend on both ecological and socioeconomic factors revealed here. Understanding these relationships is a necessary step toward mitigating human impacts on land. [ABSTRACT FROM AUTHOR]

Human-aided transport is responsible for many contemporary species introductions, yet the contribution of human-aided transport to dispersal within non-native regions is less clear. Understanding dispersal dynamics for invasive species can streamline mitigation efforts by targeting routes that contribute disproportionally to spread. Because of its limited natural dispersal ability, rapid spread of the Asian tiger mosquito ( Aedes albopictus) has been attributed to human-aided transport, but until now, the relative roles of human-aided and natural movement have not been rigorously evaluated. Here, we use landscape genetics and information-theoretic model selection to evaluate 52 models representing 9240 pairwise dispersal paths among sites across the US range for Ae. albopictus and show that recent gene flow reflects a combination of natural and human-aided dispersal. Highways and water availability facilitate dispersal at a broad spatial scale, but gene flow is hindered by forests at the current distributional limit (range edge) and by agriculture among sites within the mosquito's native climatic niche (range core). Our results show that highways are important to genetic structure between range-edge and range-core pairs, suggesting a role for human-aided mosquito transport to the range edge. In contrast, natural dispersal is dominant at smaller spatial scales, reflecting a shifting dominance to natural movement two decades after introduction. These conclusions highlight the importance of (i) early intervention for species introductions, particularly those with readily dispersed dormant stages and short generation times, and (ii) strict monitoring of commercial shipments for transported immature stages of Ae. albopictus, particularly towards the northern edge of the US range. [ABSTRACT FROM AUTHOR]

Ophiocordyceps fungi manipulate the behaviour of their ant hosts to produce a summit disease phenotype, thereby establishing infected ant cadavers onto vegetation at elevated positions suitable for fungal growth and transmission. Multiple environmental and ecological factors have been proposed to shape the timing, positioning and outcome of these manipulations.We conducted a long‐term field study of Ophiocordyceps camponoti‐floridani infections of Camponotus floridanus ants—the Florida zombie ants. We propose and refine hypotheses on the factors that shape infection outcomes by tracking the occurrence of and fungal growth from hundreds of ant cadavers. We modelled and report these data in relation to weather, light, vegetation and attack by hyperparasites.We investigated environmental factors that could affect the occurrence and location of newly manipulated ant cadavers. New cadaver occurrence was preferentially biased towards epiphytic Tillandsia bromeliads, canopy openness and summer weather conditions (an interactive effect of temperature, humidity and precipitation). Furthermore, we suggest that incident light at the individual cadaver level reflects microhabitat choice by manipulated ants or selective pressure on cadaver maintenance for conditions that improve fungal survival.We also asked which environmental conditions affect fungal fitness. Continued fungal development of reproductive structures and putative transmission increased with moist weather conditions (interaction of humidity and precipitation) and canopy openness, while being reduced by hyperparasitic mycoparasite infections. Moreover, under the most open canopy conditions, we found an atypical Ophiocordyceps growth morphology that could represent a plastic response to conditions influenced by high light levels.Taken together, we explore general trends and the effects of various ecological conditions on host and parasite disease outcomes in the Florida zombie ant system. These insights from the field can be used to inform experimental laboratory setups that directly test the effects of biotic and abiotic factors on fungus–ant interactions or aim to uncover underlying molecular mechanisms. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Physical activity (PA) is related to colorectal cancer (CRC) mortality, with approximately 15% of CRC deaths worldwide attributable to physical inactivity. Moreover, higher levels of PA in CRC survivors have been associated with a reduced risk of the disease recurring. Despite the recognised nexus between PA and the risk of CRC, the physiological mechanisms underlying the inverse relationship between PA and mortality following CRC diagnosis are less apparent, with evidence primarily drawn from epidemiological studies. The insulin-like growth factor (IGF) axis plays a central role in cellular growth, proliferation regulation, differentiation and apoptosis. Specifically, high levels of insulin-like growth factor 1 (IGF-1) have been consistently linked to the severity of CRC tumours. Further, insulin-like growth factor binding protein 3 (IGFBP-3) regulates the bioavailability of IGF-I and therefore plays a central role in CRC prognosis. Decreasing levels of IGF-1 and increasing levels of IGFBP-3 may thus be a plausible mechanism underlying the inverse association between PA and CRC survival. [ABSTRACT FROM AUTHOR]

Land use (e.g. urbanization, agriculture, natural lands management) may directly affect populations by habitat loss and fragmentation, and indirectly by altering conditions needed for reproductive success. The effects of urbanization are especially pronounced for populations that remain among urbanized areas, but they are difficult to detect in long-lived species., We evaluated the effects of urbanization on the recruitment of cypress ( Taxodium distichum), a long-lived coniferous tree that dominates isolated wetlands in Orlando, Florida, USA, a rapidly urbanizing region. Cypress requires saturated but not flooded soils to germinate, and seedlings are easily out-competed in the absence of fire. We hypothesized that urbanization has altered the hydrology and fire regimes, leading to biological inertia and reduced cypress recruitment relative to managed forest and ranchland., We found low cypress recruitment in urban areas, but surprisingly in managed forest as well. Many cypress populations in managed forest were bounded by fire breaks which prevent upland fires from burning into the wetlands. Ranchland had significantly more recruitment than urban and managed forest, and these wetlands did not have fire breaks., In urban lands, the effects of urbanization were delayed. Cypress recruitment initially occurred near the edge of wetlands where hydrological conditions were most favourable, but virtually stopped at 20 years post-urbanization. Cypress recruitment also occurred near the edge of the wetlands in managed forests and ranchlands and was higher in larger wetlands., Synthesis and applications. Urbanization is associated with the eventual reproductive failure of cypress and in the absence of management practice changes, cypress recruitment may cease in many additional wetlands. If past urbanization rates continue, 80-90% of cypress populations in isolated wetlands in the path of urban sprawl could permanently cease recruitment in 100 years. Reducing urban sprawl and introducing prescribed fire in managed-forest cypress domes could mitigate this effect and conserve reproduction of this long-lived, dominant tree species and the diversity of the wetlands they typify. [ABSTRACT FROM AUTHOR]

The article discusses the impact of wrestling on the physiological and skills requirements in small-sided games. An overview of the game filmed to follow the number of possessions and quality of disposals along with the help of global positioning system unit is provided. The study reports that the games with wrestling show significant accelerations and repeated high-intensity efforts on body movements of the players.

Although ecology and biogeography had common origins in the natural history of the nineteenth century, they diverged substantially during the early twentieth century as ecology became increasingly hypothesis-driven and experimental. This mechanistic focus narrowed ecology's purview to local scales of time and space, and mostly excluded large-scale phenomena and historical explanations. In parallel, biogeography became more analytical with the acceptance of plate tectonics and the development of phylogenetic systematics, and began to pay more attention to ecological factors that influence large-scale distributions. This trend towards unification exposed problems with terms such as 'community' and 'niche,' in part because ecologists began to view ecological communities as open systems within the contexts of history and geography. The papers in this issue represent biogeographic and ecological perspectives and address the general themes of (i) the niche, (ii) comparative ecology and macroecology, (iii) community assembly, and (iv) diversity. The integration of ecology and biogeography clearly is a natural undertaking that is based on evolutionary biology, has developed its own momentum, and which promises novel, synthetic approaches to investigating ecological systems and their variation over the surface of the Earth. We offer suggestions on future research directions at the intersection of biogeography and ecology. [ABSTRACT FROM AUTHOR]

Both biogeography and ecology seek to understand the processes that determine patterns in nature, but do so at different spatial and temporal scales. The two disciplines were not always so different, and are recently converging again at regional spatial scales and broad temporal scales. In order to avoid confusion and to hasten progress at the converging margins of each discipline, the following papers were presented at a symposium in the International Biogeography Society's 2011 meeting, and are now published in this issue of the Philosophical Transactions of the Royal Society B. In a novel approach, groups of authors were paired to represent biogeographic and ecological perspectives on each of four topics: niche, comparative ecology and macroecology, community assembly, and diversity. Collectively, this compilation identifies points of agreement and disagreement between the two views on these central topics, and points to future research directions that may build on agreements and reconcile differences. We conclude this compilation with an overview on the integration of biogeography and ecology. [ABSTRACT FROM AUTHOR]

Community ecologists often compare assemblages. Alternatively, one may compare species distributions among assemblages for macroecological comparisons of species niche traits and dispersal abilities, which are consistent with metacommunity theory and a regional community concept. The aim of this meta-analysis is to use regressions of ranked species occupancy curves (RSOCs) among diverse metacommunities and to consider the common patterns observed. Diverse data sets from four continents are analysed. Six regression models were translated from traditional occupancy frequency distributions (OFDs) and are distributed among four equation families. Each regression model was fitted to each of 24 data sets and compared using the Akaike information criterion. The analysed data sets encompass a wide range of spatial scales (5 cm-50 km grain, 2-7000 km extent), study scales (11-590 species, 6-5114 sites) and taxa. Observed RSOC regressions were tested for the differences in scale and taxa. Three RSOC models within two equation families (exponential and sigmoidal) are required to describe the very different data sets. This result is generally consistent with OFD research, but unlike OFD-based expectations the simple RSOC patterns are not related to spatial scale or other factors. Species occupancy in diverse metacommunities is efficiently summarized with RSOCs, and multi-model inference reliably distinguishes among alternative RSOCs. RSOCs are simple to generate and analyse and clearly identified surprisingly similar patterns among very different metacommunities. Species-specific hypotheses (e.g. niche-based factors and dispersal abilities) that depend on spatial scale may not translate to diverse metacommunities that sample regional communities. A novel set of three metacommunity succession and disturbance hypotheses potentially explain RSOC patterns and should be tested in subsequent research. RSOCs are an operational approach to the regional community concept and should be useful in macroecology and metacommunity ecology. [ABSTRACT FROM AUTHOR]

The article presents the results of a study which investigated the physiological and anthropometric characteristics of rugby league football players who were particularly skilled at tackling. An overview of related previous research is provided, along with details of the experimental protocol, which involved tackling drills and vertical jump tests.

The article presents a study which examines the tackling ability of junior elite and subelite rugby football players, focusing on relationships between tackling ability and specific anthropometric and physiological characteristics. The criteria used for assessing tackling proficiency is reviewed. Results suggest that acceleration and lower body muscular power are the most important variables when predicting tackling ability.

The article presents a study which examined the differences in skill and physiological demands of elite male rugby league players engaged in on-side and off-side games. Results suggest that the cognitive demands of on-side games are greater than those for off-side games, but the physiological and skill demands of off-side games are greater than those for on-side games.

Escherichia coli and Serratia liquefaciens, two bacterial spacecraft contaminants known to replicate under low atmospheric pressures of 2.5 kPa, were tested for growth and survival under simulated Mars conditions. Environmental stresses of high salinity, low temperature, and low pressure were screened alone and in combination for effects on bacterial survival and replication, and then cells were tested in Mars analog soils under simulated Mars conditions. Survival and replication of E. coli and S. liquefaciens cells in liquid medium were evaluated for 7 days under low temperatures (5, 10, 20, or 30°C) with increasing concentrations (0, 5, 10, or 20%) of three salts (MgCI2, MgSO4, NaCI) reported to be present on the surface of Mars. Moderate to high growth rates were observed for E. coli and S. liquefaciens at 30 or 20°C and in solutions with 0 or 5% salts. In contrast, cell densities of both species generally did not increase above initial inoculum levels under the highest salt concentrations (10 and 20%) and the four temperatures tested, with the exception that moderately higher cell densities were observed for both species at 10% MgSO4 maintained at 20 or 30°C. Growth rates of E. coli and S. liquefaciens in low salt concentrations were robust under all pressures (2.5, 10, or 101.3 kPa), exhibiting a general increase of up to 2.5 orders of magnitude above the initial inoculum levels of the assays. Vegetative E. coli cells were maintained in a Mars analog soil for 7 days under simulated Mars conditions that included temperatures between 20 and -50°C for a day/night diurnal period, UVC irradiation (200 to 280 nm) at 3.6 W m-2 for daytime operations (8 h), pressures held at a constant 0.71 kPa, and a gas composition that included the top five gases found in the martian atmosphere. Cell densities of E. coli failed to increase under simulated Mars conditions, and survival was reduced 1 to 2 orders of magnitude by the interactive effects of desiccation, UV irradiation, high salinity, and low pressure (in decreasing order of importance). Results suggest that E. coli may be able to survive, but not grow, in surficial soils on Mars. [ABSTRACT FROM AUTHOR]

Isolation by distance (IBD) has been a common measure of genetic structure among populations and is based on Euclidean distances among populations. Whereas IBD does not incorporate geographic complexity (e.g. dispersal barriers, corridors) that may better predict genetic structure, a new approach (landscape genetics) joins landscape ecology with population genetics to better model genetic structure. Should IBD be set aside or should it persist as the most simple model in landscape genetics? We evaluated the status of IBD by collecting and analyzing results of 240 IBD data sets among diverse taxa and study systems. IBD typically represented a low proportion of variance in genetic structure (mean r2=0.22) in part because many studies included relatively few populations (mean=11). The number of populations studied (N) was asymptotically related to IBD significance; a study with 9 populations has only 50% probability of significance, while one with >23 populations will have 90% probability of significance. Surprisingly, ectothermic animals were significantly (p=0.0018) more likely to have significant IBD than endotherms, which suggests a metabolic basis underlying gene flow rates. We also observed marginally significant effects on IBD significance for a) taxa in general and b) dispersal modes within actively-dispersing endotherms. Other factors analyzed (genetic markers, genetic distances, habitats, active or passive dispersal, plant growth form) did not significantly affect IBD, likely related to typical N. For multiple reasons we conclude that IBD should continue as the simplest reference standard against which all other, more complex models should be compared in landscape genetics research. [ABSTRACT FROM AUTHOR]

Australian Football, the most popular football code in Australia, is a contact sport played by two teams of 18 players who contest play over four 20-minute quarters; the object of the game is to score the most points through goal kicking. Sixteen professional senior sides compete against each other in the Australian Football League (AFL) and, similar to other football codes, game demands at the elite level in the AFL have changed considerably in recent years. Early time-motion analysis studies highlighted the long periods of time players spent in low intensity activities (standing and walking). While recent studies utilizing global positioning systems (GPS) technology are somewhat in agreement with earlier findings, available evidence suggests that the game is getting faster. For example, 'playing on' after a mark (a feature of the game where players who catch the ball on the full from a kick longer than 15m are awarded a free kick) is now much quicker. Indeed, rule changes in recent years have increased the flow and speed of the game; there has been a reduction in the time taken for umpires to restart play, and for players to kick-in (after the opposition kicks a behind) or take a set shot at goal. Nomadic players (a broad term for midfielders and ruckmen because they follow play over the entire playing field) cover slightly greater distances (12 310m) than both forwards (11 920m) and backs (11 880m) in a game. Compared with players in other positions, midfielders are consistently found to spend the most time at higher intensities (running and sprint efforts with movement velocities >4.44 m/sec), complete more high intensity efforts (∼98 per game), sustain them for longer and have shorter recovery periods between high intensity exercise bouts (∼90 seconds on average). 'Ruckmen' have similar but less intense running profiles, while forwards and backs generally have less game involvement but have a more intermittent running profile (longer recovery periods with shorter duration high intensity exercise bouts and less time spent in constant pace running). Endurance fitness remains very important for players at the elite level of competition, as does upper and lower body strength and power. In addition, given the increasing speed at which Australian Football is now played, repeated sprint ability of players is arguably more important now than it was in previous years. There are no significant differences in these measures between playing position. Similarly, speed over 10-40m does not appear to differ between playing position. Establishing the reliability of distance and velocity-derived GPS data in highly specific game-related activities is needed; once achieved, GPS data have the potential to accurately inform coaches of the position-specific demands on their players and to drive the development of training practices that reflect the changing demands of the game. [ABSTRACT FROM AUTHOR]

Aim The peninsula effect is the prediction that the number of species declines from a peninsula's base to its tip. We evaluated evidence for and against the peninsula effect, and conducted a field study designed to test alternative hypotheses for that effect. Location The Florida peninsula, USA. Methods First, we critically reviewed the accumulated literature on peninsula effects; second, we sampled microcrustaceans in palustrine wetlands on the ridges of peninsular Florida. Site selection in our field study accounted for historical effects and partially controlled for habitat effects. Statistical analyses further accounted for habitat effects, leaving peninsular geometry as the remaining causative mechanism for residual variation in species richness regression analyses. Results Our literature review found mixed evidence (49% of cases) for a peninsula effect. However, most study designs did not control for alternative hypotheses, most comparisons of alternative hypotheses were qualitative, and most studies focused on vertebrate animals. Our field study found that freshwater microcrustaceans inhabiting isolated wetlands on Florida’s peninsular ridges do not exhibit a peninsula effect. Essentially, no variation in microcrustacean species richness could be attributed to peninsular geometry, but 82.5% of variation in species richness was attributed to habitat and sampling effort. Main conclusions Although our research results support the ‘red herring’ label for the peninsula effect, our literature review leads us to argue that more illumination (in the form of study design and quantitative analysis) is needed if mechanisms causing the peninsula effect hypothesis are to be resolved. Future studies of peninsula effects need to control for alternative causative hypotheses (geometry, habitat or history) in study design, and compare quantitatively the effects of hypothesized mechanisms on peninsular diversity patterns. Additionally, studies of taxa other than vertebrate animals need to be conducted for generality. Our study may serve as an example of such an approach. [ABSTRACT FROM AUTHOR]

OBJECTIVES: Hypnotherapy is effective in several diseases with a psychosomatic component. Our aim was to study the effects of one session of hypnosis on the systemic and rectal mucosal inflammatory responses in patients with active ulcerative colitis (UC). METHODS: In total, 17 patients with active UC underwent a 50-min session of gut-focused hypnotherapy. Before and after each procedure, the systemic inflammatory response was assessed by serum interleukin (IL)-6 and IL-13 concentrations, tumor necrosis factor-alpha (TNF-α) and IL-6 production by lipopolysaccharide (LPS)-stimulated whole blood, leukocyte count, natural killer (NK) cell number, platelet activation, and platelet–leukocyte aggregate formation. Rectal inflammation was assessed by mucosal release of substance P (SP), histamine, IL-13 and TNF-α, reactive oxygen metabolite production, and mucosal blood flow. Eight patients with active UC underwent a control procedure. RESULTS: Hypnosis decreased pulse by a median 7 beats per minute (bpm) ( P= 0.0008); it also reduced the median serum IL-6 concentration by 53% ( P= 0.001), but had no effect on the other systemic variables assessed. Hypnosis reduced rectal mucosal release of SP by a median 81% ( P= 0.001), histamine by 35% ( P= 0.002) and IL-13 by 53% ( P= 0.003), and also, blood flow by 18% ( P= 0.0004). The control protocol had no effect on any of the variables assessed. CONCLUSIONS: Hypnosis reduced several components of the systemic and mucosal inflammatory response in active ulcerative colitis toward levels found previously in the inactive disease. Some of these effects may contribute to the anecdotally reported benefits of hypnotherapy and provide a rationale for controlled trials of hypnotherapy in UC. [ABSTRACT FROM AUTHOR]

Aim The aim of this study is to answer the questions: (1) do small organisms disperse farther than large, or vice versa; and (2) does the observed pattern differ for passive and active dispersers? These questions are central to several themes in biogeography (including microbial biogeography), macroecology, metacommunity ecology and conservation biology. Location The meta-analysis was conducted using published data collected worldwide. Methods We collected and analysed 795 data values in the peer-reviewed literature for direct observations of both maximal dispersal distance and mass of the dispersing organisms (e.g. seeds, not trees). Analysed taxa ranged in size from bacteria to whales. We applied macroecology analyses based on null models (using Monte Carlo randomizations) to test patterns relative to specific hypotheses. Results Collected dispersal distance and mass data spanned 9 and 21 orders of magnitude, respectively. Active dispersers dispersed significantly farther ( P < 0.001) and were significantly greater in mass ( P < 0.001) than passive dispersers. Overall, size matters: larger active dispersers attained greater maximum observed dispersal distances than smaller active dispersers. In contrast, passive-disperser distances were random with respect to propagule mass, but not uniformly random, in part due to sparse data available for tiny propagules. Conclusions Size is important to maximal dispersal distance for active dispersers, but not for passive dispersers. Claims that microbes disperse widely cannot be tested by current data based on direct observations of dispersal: indirect approaches will need to be applied. Distance–mass relationships should contribute to a resolution of neutral and niche-based metacommunity theories by helping scale expectations for dispersal limitation. Also, distance–mass relationships should inform analyses of latitudinal species richness and conservation biology topics such as fragmentation, umbrella species and taxonomic homogenization. [ABSTRACT FROM AUTHOR]

The article presents a study on oxidative stress in half and full Ironman triathletes. The study examined and compared pre- and postrace markers of oxidative stress in ultra endurance athletes training for a competion. The half Ironman triathletes had significantly higher erythrocytes glutathione peroxidase (GPX) activity at rest whereas the Ironman triathletes had significantly lower resting plasma malondialdehyde and significantly greater resting activities of GPX and catalese compared with controls.

Alternative models of community assembly emphasize regional, stochastic, dispersal-based processes or local, deterministic, niche-based processes. Community ecology's historical focus on local processes implicitly assumes that local processes surpass regional processes over time or across space to derive nonrandom metacommunity structure (i.e., a quorum effect). Quorum effects are expected late in succession among nearby sites, whereas quorum effects are not expected early in succession among distant sites, l conducted a metaanalysis of zooplankton data sets encompassing time scales of one to thousands of years and spatial scales of < 1 m to thousands of kilometers. Species co-occurrence analyses statistically evaluated presence/absence patterns relative to random patterns obtained with Monte Carlo null models. A series of weighted analyses was conducted and alternative randomization algorithms and null models were evaluated. Most zooplankton metacommunities were randomly structured in unweighted analyses, and the distribution of significant structure did not follow quorum effect predictions. Weighted analyses (e.g., by habitat area) revealed significant, nonrandom structure in most zooplankton metacommunities, but the distribution of significant structure still did not adhere well to quorum effect predictions. Finally, additional weighting for study scale (number of sites) nullified most significant area-weighted structure, and again, the distribution of significant structure did not follow quorum effect predictions. Overall, a quorum effect was not supported, perhaps related to zooplankton life histories and energetics and/or the quorum effect itself. Results at the presence/absence level of resolution indicated that local processes did not generally override regional processes over time or across space to drive community structure. A full integration of dispersal- and niche-based concepts in metacommunity dynamics will be most fruitful for unraveling community assembly. Species co-occurrence analyses were scale dependent (habitat area and study size). Future analyses should use weights for important factors (e.g., habitat area), and meta-analyses should include study scale as an additional factor contributing to apparent patterns. [ABSTRACT FROM AUTHOR]

Abstract Traditional expectations for how widely and how often freshwater invertebrates disperse differ from empirical data. Freshwater invertebrates have been characterized as frequent, widespread dispersers, particularly those that are transported passively. Our review finds that this characterization may describe the potential for dispersal in some taxa, but it is not an accurate generalization for actual dispersal rates. High variance among habitats and taxonomic groups is a consistent theme. Advances in population genetics may help resolve these issues, but underlying assumptions should be carefully tested. Further, even unbiased estimates of gene flow may not equate with individual movement, because not all dispersers survive and reproduce. Some freshwater invertebrates may exist in classic Levins metapopulations. However, other species fit into a broader metapopulation definition, where temporal dispersal via diapause is functionally equivalent to spatial dispersal. In the latter case, local extinctions and rescue effects may be rare or absent. Finally, limited dispersal rates in many taxa suggest that theories of freshwater community assembly and structure can be made more robust by integrating dispersal and local processes as joint, contingent regulators. Recent research on freshwater invertebrate dispersal has substantially advanced our basic and applied understanding of freshwaters, as well as evolutionary ecology in general. [ABSTRACT FROM AUTHOR]

Much of Illinois was once wet prairie, dotted with ancient (ca. 10,000-year-old) ephemeral wetlands. Most wetland habitat (85%) was converted to agriculture over a span of about 100 years (ca. 1850–1950). The consequences of this severe habitat fragmentation on wetland communities and metapopulations are unknown. We studied crustacean communities (weekly stovepipe samples throughout hydroperiods) for 3 years in a set of extant ephemeral wetlands in Illinois. We generated species-sites curves by rarefaction and extrapolated those curves to conservatively estimate that 83–85 crustacean species may have inhabited approximately 4 million ephemeral wetlands that once existed in Illinois; 8–9 crustacean species were driven to extinction in Illinois during drainage; and 75–76 crustacean species are extant in the few remaining ephemeral wetlands of Illinois. We also conducted cellular automata simulations to examine the potential effects of habitat fragmentation on the genetic structure of extant crustacean metapopulation. Simulations indicated that conversion of the former wet prairie to agriculture may have reduced crustacean metapopulations to isolated populations that are more vulnerable to future habitat loss. Despite severe habitat fragmentation, curvilinear species-sites relationships suggest that the greatest extinction rates have yet to occur for ephemeral wetland crustaceans. However, selection for limited dispersal during habitat fragmentation may contribute to extinction debt for extant species. Conservation programs can preserve much of the historical biodiversity of ephemeral wetlands, but future wetland biodiversity will depend heavily on the success of those efforts. The consequences of historical wetland loss and the importance of wetland conservation efforts to agriculture in the United States should be instructive for other regions. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the effects of 7 weeks of high- and low-velocity resistance training on strength and sprint running performance in nine male elite junior sprint runners (age 19.0 ± 1.4 years, best 100 m times 10.89 ± 0.21 s; mean ± s). The athletes continued their sprint training throughout the study, but their resistance training programme was replaced by one in which the movement velocities of hip extension and flexion, knee extension and flexion and squat exercises varied according to the loads lifted (i.e. 30–50% and 70–90% of 1-RM in the high- and low-velocity training groups, respectively). There were no between-group differences in hip flexion or extension torque produced at 1.05, 4.74 or 8.42 rad·s[sup -1], 20 m acceleration or 20 m 'flying' running times, or 1-RM squat lift strength either before or after training. This was despite significant improvements in 20 m acceleration time (P < 0.01), squat strength (P < 0.05), isokinetic hip flexion torque at 4.74 rad·s[sup -1] and hip extension torque at 1.05 and 4.74 rad·s[sup -1] for the athletes as a whole over the training period. Although velocity-specific strength adaptations have been shown to occur rapidly in untrained and non-concurrently training individuals, the present results suggest a lack of velocity-specific performance changes in elite concurrently training sprint runners performing a combination of traditional and semi-specific resistance training exercises. [ABSTRACT FROM AUTHOR]

Studies zooplankton community structure and function in experimental ponds to evaluate assumptions of environmental similarity among ponds. Analyses of species presence, colonization and species accrual curves and taxa; Dispersal as regulator of new zooplankton communities.

A 12 week kayak training programme was evaluated in children who either had or did not have the anthropometric characteristics identified as being unique to senior elite sprint kayakers. Altogether, 234 male and female school children were screened to select 10 children with and 10 children without the identified key anthropometric characteristics. Before and after training, the children completed an all-out 2 min kayak ergometer simulation test; measures of oxygen consumption, plasma lactate and total work accomplished were recorded. In addition, a 500 m time trial was performed at weeks 3 and 12. The coaches were unaware which 20 children possessed those anthropometric characteristics deemed to favour development of kayak ability. All children improved in both the 2 min ergometer simulation test and 500 m time trial. However, boys who were selected according to favourable anthropometric characteristics showed greater improvement than those without such characteristics in the 2 min ergometer test only. In summary, in a small group of children selected according to anthropometric data unique to elite adult kayakers, 12 weeks of intensive kayak training did not influence the rate of improvement of on-water sprint kayak performance. [ABSTRACT FROM AUTHOR]

Background: Despite an overwhelming body of evidence showing the benefits of physical activity (PA) and exercise for cancer survivors, few survivors meet the exercise oncology guidelines. Moreover, initiating, let alone maintaining exercise programs with cancer survivors continues to have limited success. The aim of this trial is to evaluate the influence of peer support on moderate-to-vigorous PA (MVPA) and various markers of health 12 months following a brief supervised exercise intervention in cancer survivors.Methods: Men and women previously diagnosed with histologically-confirmed breast, colorectal or prostate cancer (n = 226), who are >1-month post-treatment, will be invited to participate in this trial. Once enrolled, participants will complete 4 weeks (12 sessions) of supervised high intensity interval training (HIIT). On completion of the supervised phase, both groups will be provided with written recommendations and verbally encouraged to achieve three HIIT sessions per week, or equivalent exercise that meets the exercise oncology guidelines. Participants will be randomly assigned to receive 12 months of peer support, or no peer support (control). Primary and secondary outcomes will be assessed at baseline, after the 4-week supervised HIIT phase and at 3-, 6- and 12-months. Primary outcomes will include accelerometry-derived MVPA and prescribed HIIT session adherence; whilst secondary outcomes will include cardiorespiratory fitness ([Formula: see text]), body composition, quality of life and select cytokines, myokines and inflammatory markers. Random effects mixed modelling will be used to compare mean changes in outcomes between groups at each time point. A group x time interaction will be used to formally test for differences between groups (alpha =0.05); utilising intention-to-treat analyses.Discussion: If successful, peer support may be proposed, adopted and implemented as a strategy to encourage cancer survivors to maintain exercise beyond the duration of a short-term, supervised intervention. A peer support-exercise model has the long-term potential to reduce comorbidities, improve physical and mental wellbeing, and significantly reduce the burden of disease in cancer survivors.Ethics: Human Research Ethics Committee of Bellberry Ltd. (#2015-12-840).Trial Registration: Australian New Zealand Clinical Trial Registry 12618001855213 . Retrospectively registered 14 November 2018. Trial registration includes all components of the WHO Trial Registration Data Set, as recommended by the ICMJE. [ABSTRACT FROM AUTHOR]

Ants are a widespread group of ecologically important insects. Therefore, ants that are important predators of other ants are likely to play key roles by changing the abundance and impacts of their prey. Familiar arthropod predators, like army ants, are known for their overwhelming raids on invertebrate prey but are limited to mostly tropical systems. Thief ants (Genus: Solenopsis Westwood) are a cosmopolitan group of mostly subterranean ants found in a wide variety of ecosystem types. They are known for their extremely small sizes and their specialized predation where they stealthily tunnel into the nests of other larger ant species to capture and consume only immature ants (larvae and pupae). Predation of ant colonies by other ants, and specialized predatory behaviors of presumed top ant predators (e.g., army ants) are well known. However long‐term predation effects, such as across several seasons, are still poorly understood because of a lack of experimental studies. Here we report results of a ~1.5‐year press field experiment where thief ants were reduced in natural ant communities. Potential impacts, such as predator‐release, were quantified by sampling the co‐occurring ant community. Compared to control plots, overall worker abundance and biomass increased where thief ants were reduced, and effects varied among ant species. Results suggest predator release as select aboveground foraging ant species increased in abundance and that thief ants may act as significant predators. Because thief ants are abundant and widespread, similar predatory effects may occur in many ant communities, and our understanding of important predators may need to adjust to include thieving species as well as army ants. Thief ants are very abundant, tiny, specialized to consume immature life stages, equipped with powerful venom, eusocial, and subterranean. This suite of adaptive traits seems unique to eusocial predators compared to animals, where "thieving" predators are usually larger in size compared to their adult‐sized prey. Future work quantifying top‐down regulation of prey and cascading consumptive and non‐consumptive effects will help to understand thief ant predation and potential effects on ecosystem processes. [ABSTRACT FROM AUTHOR]

Rapid adaptation in response to novel environments can facilitate species invasions and range expansions. Understanding how invasive disease vectors rapidly evolve to novel conditions—particularly at the edge of its non‐native range—has important implications for mitigating the prevalence and spread of disease.Here, we evaluate the role of local adaptation in overwintering capability of the Asian tiger mosquito, Aedes albopictus. This species invaded the Southern United States in the 1980s and rapidly spread northward into novel climate compared to its native range. Photoperiodically induced egg diapause is a key trait contributing to the establishment and spread of Ae. albopictus in temperate latitudes, and diapause incidence rapidly developed a cline along a latitudinal gradient in the United States shortly after its initial invasion. However, variation in overwintering survival of diapause‐induced eggs along this gradient is not known, but is critical to the fitness‐related role of diapause evolution in the establishment of Ae. albopictus in its northern US range.Using reciprocal transplants, we detected local adaptation in overwinter survival of diapausing Aedes albopictus eggs. In northern range‐edge winters, eggs produced by range‐edge individuals survived better than those produced by range‐core individuals. Diapause eggs from range‐edge and range‐core locations survived equally well in range‐core winters, and no eggs survived a winter beyond the current northern range limit in the United States.Synthesis and applications. These results demonstrate rapid (~3 decades) local adaptation of egg diapause, a key trait facilitating overwinter survival and range expansion for the invasive Asian tiger mosquito. In light of these results, control efforts could shift from targeting satellite populations to a focus on preventing dispersal into locally adapted, range‐edge locations and to aim removal efforts towards areas surrounding locally adapted populations. Adopting new approaches to target rapidly adapting populations will require large‐scale collaboration among control agencies and research institutions, and should begin in the northern US range to better control Aedes albopictus mosquito populations in the face of rapid adaptation. [ABSTRACT FROM AUTHOR]