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The Altamira Yellowthroat Geothlypis flavovelata is endemic to north-eastern Mexico, with a restricted distribution due to the spatial arrangement of its major habitat: wetlands. Given the lack of information regarding this vulnerable and endemic landbird, here we describe and analyse the sites where we recorded it in Northern Veracruz, as well as its population density, and natural history information. Our results show that the average density of this endemic yellowthroat is 1.006 ind/ha, with more individuals recorded in Tecolutla when compared to Tuxpan. We found a strong association between the Altamira Yellowthroat and southern cat-tail Typha domingensis, although we found scenarios under which the presence of the cat-tail was not a determinant of Altamira Yellowthroat presence. In light of the strong anthropogenic pressures on wetlands in the region, the Altamira Yellowthroat has become highly vulnerable. Thus, if we aim to preserve this endemic species, together with other wetland-dependent species, it is crucial to moderate –and even stop– human pressures on these ecosystems and mitigate past damages.
The rocky shores of the north-east Atlantic have been long studied. Our focus is from Gibraltar to Norway plus the Azores and Iceland. Phylogeographic processes shape biogeographic patterns of biodiversity. Long-term and broadscale studies have shown the responses of biota to past climate fluctuations and more recent anthropogenic climate change. Inter- and intra-specific species interactions along sharp local environmental gradients shape distributions and community structure and hence ecosystem functioning. Shifts in domination by fucoids in shelter to barnacles/mussels in exposure are mediated by grazing by patellid limpets. Further south fucoids become increasingly rare, with species disappearing or restricted to estuarine refuges, caused by greater desiccation and grazing pressure. Mesoscale processes influence bottom-up nutrient forcing and larval supply, hence affecting species abundance and distribution, and can be proximate factors setting range edges (e.g., the English Channel, the Iberian Peninsula). Impacts of invasive non-native species are reviewed. Knowledge gaps such as the work on rockpools and host–parasite dynamics are also outlined.
With respect to De Dreu and Gross's article, we comment on the psychological functions for attack and defense, focusing on associations between individual differences in psychopathic personality traits and the behavioral patterns observed in attack-defense conflicts. We highlight the dimensional nature of psychopathy and formulate hypothetical associations between distinct traits, their different behavioral outcomes, and associated brain mechanisms.
Over recent decades, biomass gains in remaining old-growth Amazonia forests have declined due to environmental change. Amazonia’s huge size and complexity makes understanding these changes, drivers, and consequences very challenging. Here, using a network of permanent monitoring plots at the Amazon–Cerrado transition, we quantify recent biomass carbon changes and explore their environmental drivers. Our study area covers 30 plots of upland and riparian forests sampled at least twice between 1996 and 2016 and subject to various levels of fire and drought. Using these plots, we aimed to: (1) estimate the long-term biomass change rate; (2) determine the extent to which forest changes are influenced by forest type; and (3) assess the threat to forests from ongoing environmental change. Overall, there was no net change in biomass, but there was clear variation among different forest types. Burning occurred at least once in 8 of the 12 riparian forests, while only 1 of the 18 upland forests burned, resulting in losses of carbon in burned riparian forests. Net biomass gains prevailed among other riparian and upland forests throughout Amazonia. Our results reveal an unanticipated vulnerability of riparian forests to fire, likely aggravated by drought, and threatening ecosystem conservation at the Amazon southern margins.
The South China Sea (SCS) is a biodiversity hotspot, however, most biodiversity surveys in the region are confined to shallow water reefs. Here, we studied the benthic habitat and fish assemblages in the upper mesophotic coral ecosystems (MCEs; 30–40 m) and SWRs (8–22 m) at three geographic locations (Luzon Strait; Palawan; and the Kalayaan Group of Islands) in the eastern SCS (also called the West Philippine Sea) using diver-based survey methods. Mean coral genera and fish species richness ranged from 17–25 (per 25 m2) and 11–17 (per 250 m2) in MCEs, respectively; although none of these were novel genera/species. Coral and fish assemblages were structured more strongly by location than by depth. Location differences were associated with the variability in benthic composition, wherein locations with higher hard coral cover had higher coral genera richness and abundance. Locations with higher algae and sand cover had higher diversity and density of fish herbivores and benthic invertivores. Fishing efforts may also have contributed to among-location differences as the highly exploited location had the lowest fish biomass. The low variation between depths may be attributed to the similar benthic composition at each location, the interconnectivity between depths due to hydrological conditions, fish motility, and the common fishing gears used in the Philippines that can likely extend beyond SWRs. Results imply that local-scale factors and anthropogenic disturbances probably dampen across-depth structuring in coral genera and fish species assemblages.
The Endangered Asian elephant Elephas maximus comes into widespread conflict with agrarian communities, necessitating active management. The species’ distribution is of primary importance for management planning. However, data-based countrywide distribution maps have not been available for any of the 13 Asian elephant range states. We conducted a 5 × 5 km grid-based questionnaire survey in Sri Lanka to produce an island-wide elephant distribution map. Elephants occur over 59.9% of Sri Lanka and people are resident in 69.4% of elephant range, indicating the challenge of separating people and elephants at a landscape scale. Elephants in Sri Lanka have lost 16.1% of their range since 1960 but their current distribution remains largely contiguous. We found the range of adult males was 15.1% greater, and less seasonal, than that of herds, possibly because males have a higher tolerance for conflict with people. The distribution of conflict coincided with the co-occurrence of humans and elephants. We conclude that a human–elephant coexistence model is the only viable option for effectively mitigating human–elephant conflict and conserving elephants in Sri Lanka. The findings are currently being used to effect a paradigm change in elephant conservation and management in the country.
Graded exercises tests are performed in adult populations; nonetheless, the use of this type of assessment is greatly understudied in overweight and obese adolescents.
To investigate heart rate autonomic responses to submaximal aerobic exercise in obese and overweight adolescents.
We recruited 40 adolescents divided into two groups: (1) overweight group comprising 10 boys and 10 girls between Z-score +1 and +2 and (2) obese group comprising 10 boys and 10 girls above Z-score >+2. Heart rate variability was analysed before (T1) and after exercise (T2–T4) on treadmill at a slope of 0%, with 70% of the maximal estimated heart rate (220 – age) for 20 minutes.
Heart rate in the overweight group was: 93.2±10.52 bpm versus 120.8±13.49 bpm versus 94.6±11.65 bpm versus 93.0±9.23 bpm, and in the obese group was: 92.0±15.41 bpm versus 117.6±16.31 bpm versus 92.1±12.9 bpm versus 91.8±14.33 bpm. High frequency in the overweight group was: 640±633.1 ms2 versus 84±174.66 ms2 versus 603.5±655.31 ms2 versus 762.6±807.21 ms2, and in the obese group was: 628.4±779.81 ms2 versus 65.4±119.34 ms2 versus 506.2±482.70 ms2 versus 677.9±939.05 ms2; and root mean square of successive differences in the overweight group was: 37.9±18.81 ms versus 10.9±8.41 ms versus 32.8±24.07 ms versus 36.7±21.86 ms, and in the obese group was: 38.7±23.17 ms versus 11.5±8.62 ms versus 32.3±16.74 ms versus 37.3±24.21 ms. These values significantly changed during exercise compared with resting values in overweight and obese groups. Moreover, we also reported no significant difference of resting parasympathetic control of heart rate between obese and overweight adolescents.
There was no significant difference of autonomic responses elicited by submaximal aerobic exercise between overweight and obese adolescents.
Recent open-label trials show that psychedelics, such as ayahuasca, hold promise as fast-onset antidepressants in treatment-resistant depression.
To test the antidepressant effects of ayahuasca, we conducted a parallel-arm, double-blind randomized placebo-controlled trial in 29 patients with treatment-resistant depression. Patients received a single dose of either ayahuasca or placebo. We assessed changes in depression severity with the Montgomery-Åsberg Depression Rating Scale (MADRS) and the Hamilton Depression Rating scale at baseline, and at 1 (D1), 2 (D2), and 7 (D7) days after dosing.
We observed significant antidepressant effects of ayahuasca when compared with placebo at all-time points. MADRS scores were significantly lower in the ayahuasca group compared with placebo at D1 and D2 (p = 0.04), and at D7 (p < 0.0001). Between-group effect sizes increased from D1 to D7 (D1: Cohen's d = 0.84; D2: Cohen's d = 0.84; D7: Cohen's d = 1.49). Response rates were high for both groups at D1 and D2, and significantly higher in the ayahuasca group at D7 (64% v. 27%; p = 0.04). Remission rate showed a trend toward significance at D7 (36% v. 7%, p = 0.054).
To our knowledge, this is the first controlled trial to test a psychedelic substance in treatment-resistant depression. Overall, this study brings new evidence supporting the safety and therapeutic value of ayahuasca, dosed within an appropriate setting, to help treat depression. This study is registered at http://clinicaltrials.gov (NCT02914769).
Facing a bottleneck in the growth of aquaculture, and a gap in the supply and demand of the highly beneficial n-3 long-chain PUFA (LC-PUFA), sustainable alternatives to traditional marine-based feeds are required. Therefore, in the present trial, a novel oil obtained from a genetically engineered oilseed crop, Camelina sativa, that supplied over 25 % n-3 LC-PUFA was tested as a sole dietary-added lipid source in Atlantic salmon (Salmo salar) feed. Three groups of fish were fed three experimental diets for 12 weeks with the same basal composition and containing 20 % added oil supplied by either a blend of fish oil and rapeseed oil (1:3) (COM) reflecting current commercial formulations, wild-type Camelina oil (WCO) or the novel transgenic Camelina oil (TCO). There were no negative effects on the growth, survival rate or health of the fish. The whole fish and flesh n-3 LC-PUFA levels were highest in fish fed TCO, with levels more than 2-fold higher compared with those of fish fed the COM and WCO diets, respectively. Diet TCO had no negative impacts on the evaluated immune and physiological parameters of head kidney monocytes. The transcriptomic responses of liver and mid-intestine showed only mild effects on metabolism genes. Overall, the results clearly indicated that the oil from transgenic Camelina was highly efficient in supplying n-3 LC-PUFA providing levels double that obtained with a current commercial standard, and similar to those a decade ago before substantial dietary fishmeal and oil replacement.
Here we evaluated the effect of fermented milk supplemented with whey protein (approximately 80 % protein), probiotic (Bifidobacterium animalis subsp. lactis BB12) and pomegranate juice (Punica granatum L.) on the physical performance, intestinal motility and villi structure, inflammatory markers and intestinal microbiota of rats under high-intensity acute exercise. In all, twenty-four Wistar rats were separated into groups: control (Ctrl), supplemented (Supp), exercised (Exe) and exercised and supplemented (Exe+Supp). Rats in the Supp groups received fermented milk during 6 weeks by oral administration. At the end of the supplementation period, the Exe groups were submitted to high-intensity acute exercise on a treadmill. We found that intense acute exercise caused changes in the intestinal villi interspace, changes in the proportion of Lactobacillus species and an increase in Clostridium species, as well as a decrease in intestinal motility. Supplementation increased intestinal motility, and maintained the intestinal villi interspace and the natural microbiota proportions of the exercised rats. Physical performance was not improved by fermented milk supplementation. We conclude that the fermented milk containing whey protein, B. animalis (BB12) and pomegranate juice can re-establish intestinal microbiota and protect the animals from the undesirable effects of intense acute exercise.
Mentorship is perceived to be an important component of residency education. However, evidence of the impact of mentorship on professional development in Emergency Medicine (EM) is lacking.
Online survey distributed to attending physician members of the Canadian Association of Emergency Physicians (CAEP), using a modified Dillman method. Survey contained questions about mentorship during residency training, and perceptions of the impact of mentorship on career development.
The response rate was 23.5% (309/1314). 63.6% reported having at least one mentor during residency. The proportion of participants with a formal mentorship component during residency was higher among those with mentors (44.5%) compared to those without any formal mentorship component during residency (8.0%, p<0.001). The most common topics discussed with mentors were career planning and work-life balance. The least common topics included research and finances. While many participants consulted their mentor regarding their first job (56.5%), fewer consulted their mentor regarding subspecialty training (45.1%) and research (41.1%). 71.8% chose to work in a similar centre as their mentor, but few completed the same subspecialty (24.8%), or performed similar research (30.4%). 94.1% stated that mentorship was important to success during residency. Participants in a formal mentorship program did not rate their experience of mentorship higher than those without a formal program.
Among academic EM physicians with an interest in mentorship, mentorship during EM residency may have a greater association with location of practice than academic scholarship or subspecialty choice. Formal mentorship programs increase the likelihood of obtaining a mentor, but do not appear to improve reported mentorship experiences.
There is limited knowledge on vitamin D status of children residing in the Andes and its association with undernutrition. We evaluated the vitamin D status of children residing in a low socio-economic status (SES) setting in the Ecuadorian Andes and assessed the association between vitamin D status, stunting and underweight. We hypothesized that children who were underweight would have lower serum 25-hydroxyvitamin D (25(OH)D) levels and lower 25(OH)D levels would be associated with a higher risk of stunting.
We conducted a cross-sectional secondary analysis of a randomized controlled trial, the Vitamin A, Zinc and Pneumonia study. Children had serum 25(OH)D concentrations measured. A sensitivity analysis was undertaken to determine a vitamin D cut-off specific for our endpoints. Associations between serum 25(OH)D and underweight (defined as weight-for-age Z-score≤−1) and stunting (defined as height-for-age Z-score≤−2) were assessed using multivariate logistic regression.
Children residing in five low-SES peri-urban neighbourhoods near Quito, Ecuador.
Children (n 516) aged 6–36 months.
Mean serum 25(OH)D concentration was 58·0 (sd 17·7) nmol/l. Sensitivity analysis revealed an undernutrition-specific 25(OH)D cut-off of <42·5 nmol/l; 18·6 % of children had serum 25(OH)D<42·5 nmol/l. Children who were underweight were more likely to have serum 25(OH)D<42·5 nmol/l (adjusted OR (aOR)=2·0; 95 % CI 1·2, 3·3). Children with low serum 25(OH)D levels were more likely to be stunted (aOR=2·8; 95 % CI 1·6, 4·7).
Low serum 25(OH)D levels were more common in underweight and stunted Ecuadorian children.
Multiwall carbon nanotubes (MWCNTs) are utilized to resolve low coupling coefficient issue by dispersing MWCNTs in poly(vinylidene fluoride) matrix to create stress reinforcing network, dispersant, and electron conducting functions for barium titanate (BT) nanoparticles. Various BT and MWCNT percentages of nanocomposite film are fabricated by FDM three-dimensional (3D) printing which can simplify the fabrication process as well as lower cost and design flexibility. Increasing MWCNTs and BT particles gradually increase piezoelectric coefficient (d31) by 0.13 pC/N with 0.4 wt%-MWCNTs/18 wt%-BT. These results provide not only a technique to print piezoelectric nanocomposites but also unique materials combination for sensor application.
The crystal structure of karibibite, Fe33+(As3+O2)4(As23+O5)(OH), from the Urucum mine (Minas Gerais, Brazil), was solved and refined from electron diffraction tomography data [R1 = 18.8% for F > 4σ(F)] and further confirmed by synchrotron X-ray diffraction and density functional theory (DFT) calculations. The mineral is orthorhombic, space group Pnma and unit-cell parameters (synchrotron X-ray diffraction) are a = 7.2558(3), b = 27.992(1), c = 6.5243 (3) Å, V = 1325.10(8) Å3, Z = 4. The crystal structure of karibibbite consists of bands of Fe3+O6 octahedra running along a framed by two chains of AsO3 trigonal pyramids at each side, and along c by As2O5 dimers above and below. Each band is composed of ribbons of three edge-sharing Fe3+O6 octahedra, apex-connected with other ribbons in order to form a kinked band running along a. The atoms As(2) and As(3), each showing trigonal pyramidal coordination by O, share the O(4) atom to form a dimer. In turn, dimers are connected by the O(3) atoms, defining a zig-zag chain of overall (As3+O2)n-n stoichiometry. Each ribbon of (Fe3+O6) octahedra is flanked on both edges by the (As3+O2)n-n chains. The simultaneous presence of arsenite chains and dimers is previously unknown in compounds with As3+. The lone-electron pairs (4s2) of the As(2) and As(3) atoms project into the interlayer located at y = 0 and y = ½, yielding probable weak interactions with the O atoms of the facing (AsO2) chain.
The DFT calculations show that the Fe atoms have maximum spin polarization, consistent with the Fe3+ state.
The Recorrido Arqueológico de Coixtlahuaca (RAC) presents period-by-period settlement pattern maps for the valley of Coixtlahuaca in the northern Mixteca Alta. The RAC project made improvements in full-coverage survey methods. We identify limitations and suggest that similar projects in the future need to resolve several management and budget problems. The survey revealed two periods of heavy occupation, 700–300 BC and AD 1200–1520, separated by a long period of lower population. Archaeological and historical data indicate that during the AD 1200–1520 period, and probably earlier, small landholders organized in strong communities managed an intensive agroecosystem, investing in landesque capital. Urbanization was impressive, yet cities were aggregations of communities and barrios. Today local citizens pose questions about how the large prehispanic population could have organized and sustained itself; these questions coincide with anthropological interest in collective agency, property, landesque capital, and collapse.