Potential Influences of Biotic and Abiotic Factors on Patterns of Activity in Galapagos Snakes: Locomotory Performance or Prey Abundance?

Biotic and abiotic factors were considered as the potential factors influencing the activity pattern of Galapagos snakes. Three hypothesis are tested in this study in order to examine the causes of variation in snake activity. The first hypothesis (variation in the number of snakes active throughout the day is caused by distribution and abundance of their prey) is rejected because snakes and lizards have different patterns of activity. Moreover, Chi-square Goodness-of-Fit test and 2 x 2 Contingency tables show significant differences between these patterns of activity. However there are hours of the day when lizard activity could influence snake activity. The alternate hypothesis (variation in the number of snakes active throughout the day is caused by the effect variation in environmental temperature on body temperatures of snakes) is partially falsified because low levels of activity of snakes during the midday do not correspond with the periods when the body temperatures of snakes are outside of the range of temperatures that provides fast sprint-speeds. The later hypothesis (decrease in activity of snakes during midday is response to avoiding overheating) is supported because levels of activity of the snakes are significantly greater during cloudy periods than during sunny periods. Moreover, this is supported by the Chi-square Goodness-of-Fit test. In summary, the analyses indicate that there is not a single answer to the question of rather biotic or abiotic factors contribute more. Rather it appears that there is a mix of the two

Ecophysiological observations on the body temperatures of the anurans Dendropsophus bifurcus, Rhinella marina, and Scinax ruber from upper basin Amazon in northeastern Ecuador

Ectothermic inhabitants of tropical forests are subjected to constant environmental temperatures, which determine their passive thermoregulatory strategies. We observe these trends during the summer of 2017, in the anurans Dendropsophus bifurcus, Rhinella marina, and Scinax ruber, in a tropical rainforest from the Upper Amazon Basin of Ecuador. D. bifurcus and S. ruber showed a tendency to tigmothermy, whereas R. marina presented tendencies towards heliothermy. Body temperatures (Tbs) did not differ between D. bifurcus and R. marina, but S. ruber presented a lower Tb. Our results suggest that thermal environment is influencing different thermoregulatory strategies as tigmothermy and heliothermy of frogs and toads distributed in tropical environments at low elevation

Redescripción de Anolisproboscis Peters & Orcés (Reptilia: Polychrotidae), con el descubrimiento de las hembras de la especie y comentarios sobre su distribución y taxonomía

We redescribe the enigmatic lizard Anolis proboscis based on new material collected on the Distrito Metropolitano de Quito, province of Pichincha, Ecuador. We describe the first females reported for the species, increasing the diagnosis to include sexually dimorphic data; and present new information on characters previously undescribed, such as the cranial helmet and hemipenial morphology. We propose that the nasal appendage is not a homologous apomorphic character among A. proboscis and A. phyllorhinus, thus the A. laevis species-group is not a valid clade. In fact, we suggest that A. proboscis is closely related to species previously classified as “Phenacosaurus ”; while A. phyllorhinus is part of the A. punctatus species-group. We provide new information on the distribution and natural history of A. proboscis; suggesting that it should be classified under the IUCN category and criteria of “Endangered EN B1ab (i,ii,ii) +2ab (i,ii,iii)”. We propose A. proboscis as an emblematic species of the Distrito Metropolitano de Quito, in particular for the conservation of Las Tolas and Lloa-Mindo regions.Redescribimos a la enigmática lagartija Anolis proboscis basados en nuevo material colectado en el Distrito Metropolitano de Quito, provincia de Pichincha, Ecuador. Describimos las primeras hembras conocidas de la especie, ampliando así la diagnosis con datos sobre dimorfismo sexual; y presentamos nueva información sobre caracteres antes no descritos, como el casco craneal y la morfología de los hemipenes. Proponemos que el apéndice nasal no es un carácter homólogo apomórfico entre A. proboscis y A. phyllorhinus, por lo que el grupo-de-especies A. laevis no es un clado válido. De hecho, sugerimos que A. proboscis está cercanamente relacionado con especies previamente clasificadas como Phenacosaurus; mientras que A. phyllorhinus es parte del grupo-de-especies A. punctatus. Aportamos nueva información sobre la distribución e historia natural de A. proboscis y sugerimos que sea clasificado bajo la categoría y criterios de riesgo de extinción de la lUCN de “En Peligro EN B1ab (i,ii,ii) +2ab (i,ii,iii)”. Proponemos que A. proboscis sea considerado una especie de reptil emblemática del Distrito Metropolitano de Quito, en especial para la conservación de la zonas de Las Tolas y Lloa-Mindo

Descubrimiento de dos poblaciones sobrevivientes de Sapos Arlequín (Amphibia: Bufonidae: Atelopus) en los Andes de Ecuador

We report the presence of new populations of arlequín toads belonging to Atelopus palmatus and A. nepiozomus species in the provinces of Pastaza and Loja respectively. These new findings allow us to re-evaluated and verify the conservation status of these two species. The information herein reported is a contribution to the knownlodge of the genus Atelopus on which still exist important information gaps on its taxonomy, systematics and natural history.Reportamos la presencia de nuevas poblaciones de sapos arlequines pertenecientes a las especies Atelopuspalmatus y A. nepiozomus en las provincias de Pastaza y Loja respectivamente. Estos nuevos hallazgos permiten re-evaluar y corroborar el estado de conservación de estas especies. La información aquí reportada es una contribución al conocimiento del género Atelopus sobre el cual existe todavía importantes vacíos de información sobre su taxonomía, sistemática e historia natural

Identifying adolescents at risk for suboptimal adherence to tuberculosis treatment: A prospective cohort study

Adolescents account for an estimated 800,000 incident tuberculosis (TB) cases annually and are at risk for suboptimal adherence to TB treatment. Most studies of adolescent TB treatment adherence have used surveillance data with limited psychosocial information. This prospective cohort study aimed to identify risk factors for suboptimal adherence to rifampicin-susceptible TB treatment among adolescents (10-19 years old) in Lima, Peru. We collected psychosocial data using self-administered surveys and clinical data via medical record abstraction. Applying k-means cluster analysis, we grouped participants by psychosocial characteristics hypothesized to impact adherence. Then, we conducted mixed effects regression to compare suboptimal adherence-defined as 10% of doses)-between clusters. Treatment setting (facility vs. home) and drug formulation (single drug vs. fixed dose combination) were interaction terms. Of 249 participants, 90 (36.1%) were female. Median age was 17 (IQR: 15, 16.6) years. We identified three clusters-A, B, and C-of participants based on psychosocial characteristics. Cluster C had the lowest support from caregivers, other family members, and friends; had the weakest motivation to complete TB treatment; were least likely to live with their mothers; and had experienced the most childhood adversity. Among the 118 (47.4%) participants who received facility-based treatment with single drug formulations, adherence did not differ between Clusters A and B, but Cluster C had six-fold odds of suboptimal adherence compared to Cluster A. In Clusters B and C, adherence worsened over time, but only in Cluster C did mean adherence fall below 90% within six months. Our findings have implications for the care of adolescents with TB. When caring for adolescents with low social support and other risk factors, clinicians should take extra measures to reinforce adherence, such as identifying a community health worker or peer to provide treatment support. Implementing newly recommended shorter regimens also may facilitate adherence.Revisión por pare

Timing Analysis of the 2022 Outburst of the Accreting Millisecond X-Ray Pulsar SAX J1808.4-3658: Hints of an Orbital Shrinking

We present a pulse timing analysis of NICER observations of the accreting millisecond X-ray pulsar SAX J1808.4-3658 during the outburst that started on 2022 August 19. Similar to previous outbursts, after decaying from a peak luminosity of ≃1 × 1036 erg s-1 in about a week, the pulsar entered a ~1 month long reflaring stage. Comparison of the average pulsar spin frequency during the outburst with those previously measured confirmed the long-term spin derivative of ν˙SD=−(1.15±0.06)×10−15 Hz s-1, compatible with the spin-down torque of a ≈1026 G cm3 rotating magnetic dipole. For the first time in the last twenty years, the orbital phase evolution shows evidence for a decrease of the orbital period. The long-term behavior of the orbit is dominated by an ~11 s modulation of the orbital phase epoch consistent with a ~21 yr period. We discuss the observed evolution in terms of a coupling between the orbit and variations in the mass quadrupole of the companion star

The Large Observatory For X-ray Timing: LOFT

LOFT, the Large Observatory for X-ray Timing, is a new space mission concept devoted to observations of Galactic and extra-Galactic sources in the X-ray domain with the main goals of probing gravity theory in the very strong field environment of black holes and other compact objects, and investigating the state of matter at supra-nuclear densities in neutron stars. The instruments on-board LOFT, the Large area detector and the Wide Field Monitor combine for the first time an unprecedented large effective area (~10 m2 at 8 keV) sensitive to X-ray photons mainly in the 2-30 keV energy range and a spectral resolution approaching that of CCD-based telescopes (down to 200 eV at 6 keV). LOFT is currently competing for a launch of opportunity in 2022 together with the other M3 mission candidates of the ESA Cosmic Vision Progra

The impact of surgical delay on resectability of colorectal cancer: An international prospective cohort study

AIM: The SARS-CoV-2 pandemic has provided a unique opportunity to explore the impact of surgical delays on cancer resectability. This study aimed to compare resectability for colorectal cancer patients undergoing delayed versus non-delayed surgery. METHODS: This was an international prospective cohort study of consecutive colorectal cancer patients with a decision for curative surgery (January-April 2020). Surgical delay was defined as an operation taking place more than 4 weeks after treatment decision, in a patient who did not receive neoadjuvant therapy. A subgroup analysis explored the effects of delay in elective patients only. The impact of longer delays was explored in a sensitivity analysis. The primary outcome was complete resection, defined as curative resection with an R0 margin. RESULTS: Overall, 5453 patients from 304 hospitals in 47 countries were included, of whom 6.6% (358/5453) did not receive their planned operation. Of the 4304 operated patients without neoadjuvant therapy, 40.5% (1744/4304) were delayed beyond 4 weeks. Delayed patients were more likely to be older, men, more comorbid, have higher body mass index and have rectal cancer and early stage disease. Delayed patients had higher unadjusted rates of complete resection (93.7% vs. 91.9%, P = 0.032) and lower rates of emergency surgery (4.5% vs. 22.5%, P < 0.001). After adjustment, delay was not associated with a lower rate of complete resection (OR 1.18, 95% CI 0.90-1.55, P = 0.224), which was consistent in elective patients only (OR 0.94, 95% CI 0.69-1.27, P = 0.672). Longer delays were not associated with poorer outcomes. CONCLUSION: One in 15 colorectal cancer patients did not receive their planned operation during the first wave of COVID-19. Surgical delay did not appear to compromise resectability, raising the hypothesis that any reduction in long-term survival attributable to delays is likely to be due to micro-metastatic disease