Dispersal traits may reflect dispersal distances,but dispersers may not connect populations demographically

Ecological traits that reflect movement potential are often used as proxies for measured dispersal distances. Whether such traits reflect actual dispersal is often untested. Such tests are important because maximum dispersal distances may not be achieved and many dispersal events may be unsuccessful (without reproduction). For insects, many habitat patches harbour ‘resident’ species that are present as larvae (sedentary) and adults (winged and dispersing), and ‘itinerant’ species present only as adults that have dispersed from elsewhere and fail to reproduce. We tested whether itinerancy patterns were temporally consistent, and whether itinerant and resident species differed in wing morphology, a strong correlate of flight capability. Over 3 years and at multiple locations in a 22 km stream length, we sampled larvae and adults of caddisflies in the genus Ecnomus to categorize species as residents or itinerants. Flight capacity was measured using wing size (length and area) and shape parameters (aspect ratio and the second moment of wing area). Three species of Ecnomus were residents and three species were itinerants, and patterns were consistent over 3 years. On average, itinerant species had larger wings, suggesting a greater capacity to fly long distances. Wing shape differed between species, but did not differ systematically between residents and itinerants. Wing morphology was associated with actual but not effective dispersal of some species of Ecnomus. Morphological traits may have weak explanatory power for hypotheses regarding the demographic connectedness of populations, unless accompanied by data demonstrating which dispersers contribute new individuals to populations.     

Nectar,not colour,may lure insects to their death

We experimentally demonstrate in the field that prey of the carnivorous plant Sarracenia purpurea are attracted to sugar, not to colour. Prey capture (either all taxa summed or individual common taxa considered separately) was not associated with total red area or patterning on pitchers of living pitcher plants. We separated effects of nectar availability and coloration using painted ‘pseudopitchers’, half of which were coated with sugar solution. Unsugared pseudopitchers captured virtually no prey, whereas pseudopitchers with sugar solution captured the same amount of prey as living pitchers. In contrast to a recent study that associated red coloration with prey capture but that lacked controls for nectar availability, we infer that nectar, not colour, is the primary means by which pitcher plants attract prey.     

Rights and Responsibilities of Tuberculosis Patients,and the Global Fund: A Qualitative Study

Background

Implementation of the Charter to protect patients’ rights is an important criterion to achieve patient-centered approach and receive financial support from the Global Fund. Our study aims to explore the knowledge of tuberculosis (TB) patients about their rights and responsibilities at the Chest Disease Unit of the Bahawal Victoria Hospital, Bahawalpur, Pakistan.

Methods

This was a qualitative study. The data from purposefully selected TB patients was collected by in-depth interviews. Eligibility criteria included confirmed diagnosis of TB and enrollment in the TB program. A pilot tested interview protocol was based upon the objectives of the study, and was used uniformly in each interview to maintain the consistency. The sample size was limited by applying the saturation criteria. All interviews were audiotaped and transcribed verbatim. Inductive thematic content analysis was applied to analyze the data and draw conclusions.

Results

Out of the total 16 patients, four were female, and seven were illiterate. Eight patients were known cases of multi-drug resistant TB. Analysis of the data yielded seven themes; tuberculosis care services, moral support and stigmatization, dignity and privacy, complaints, fear of losing job, information sharing and compliance to the treatment plan, and contribution to eradicate TB. First five represented the rights section while latter two were related to the responsibilities section of the Charter.

Conclusion

Discriminatory access to TB care services and the right to privacy were two major concerns identified in this study. However, the respondents recognized their responsibilities as a TB patient. To ensure uninterrupted investment from the Global Fund, there is a need to implement fair TB care policies which support human rights-based approach.     

Global mangrove root production,its controls and roles in the blue carbon budget of mangroves

Mangroves are among the most carbon-dense ecosystems worldwide. Most of the carbon in mangroves is found belowground, and root production might be an important control of carbon accumulation, but has been rarely quantified and understood at the global scale. Here, we determined the global mangrove root production rate and its controls using a systematic review and a recently formalised, spatially explicit mangrove typology framework based on geomorphological settings. We found that global mangrove root production averaged ~770 ± 202 g of dry biomass m⁻² year⁻¹ globally, which is much higher than previously reported and close to the root production of the most productive tropical forests. Geomorphological settings exerted marked control over root production together with air temperature and precipitation (r² ≈ 30%, p < .001). Our review shows that individual global changes (e.g. warming, eutrophication, drought) have antagonist effects on root production, but they have rarely been studied in combination. Based on this newly established root production rate, root-derived carbon might account for most of the total carbon buried in mangroves, and 19 Tg C lost in mangroves each year (e.g. as CO₂). Inclusion of root production measurements in understudied geomorphological settings (i.e. deltas), regions (Indonesia, South America and Africa) and soil depth (>40 cm), as well as the creation of a mangrove root trait database will push forward our understanding of the global mangrove carbon cycle for now and the future. Overall, this review presents a comprehensive analysis of root production in mangroves, and highlights the central role of root production in the global mangrove carbon budget.     

Competitive ability,not tolerance,may explain success of invasive plants over natives

When entering a new community, introduced species leave behind members of their native community while simultaneously forming novel biotic interactions. Escape from enemies during the process of introduction has long been hypothesized to drive the increased performance of invasive species. However, recent studies and quantitative syntheses find that invaders often receive similar, or even more, damage from enemies than do native species. Therefore, invasives may be those more tolerant to enemy damage, or those able to maintain competitive ability in light of enemy damage. Here, we investigate whether tolerance and competitive ability could contribute to invasive plant success. We determined whether invasive plants were more competitive than native or noninvasive exotic species in both the presence and absence of simulated herbivory. We found competition and herbivory additively reduced individual performance, and affected the performance of native, invasive, and noninvasive exotic species’ to the same degree. However, invasives exerted stronger competitive effects on an abundant native species (Elymus canadensis) in both the presence and absence of herbivory. Therefore, while invasive species responded similarly to competition and simulated herbivory, their competitive effects on natives may contribute to their success in their introduced range.     

Neandertal humeri may reflect adaptation to scraping tasks, but not spear thrusting

Unique compared with recent and prehistoric Homo sapiens, Neandertal humeri are characterised by a pronounced right-dominant bilateral strength asymmetry and an anteroposteriorly strengthened diaphyseal shape. Remodeling in response to asymmetric forces imposed during regular underhanded spear thrusting is the most influential explanatory hypothesis. The core tenet of the "Spear Thrusting Hypothesis", that underhand thrusting requires greater muscle activity on the right side of the body compared to the left, remains untested. It is unclear whether alternative subsistence behaviours, such as hide processing, might better explain this morphology. To test this, electromyography was used to measure muscle activity at the primary movers of the humerus (pectoralis major (PM), anterior (AD) and posterior deltoid (PD)) during three distinct spear-thrusting tasks and four separate scraping tasks. Contrary to predictions, maximum muscle activity (MAX) and total muscle activity (TOT) were significantly higher (all values, p<.05) at the left (non-dominant) AD, PD and PM compared to the right side of the body during spear thrusting tasks. Thus, the muscle activity required during underhanded spearing tasks does not lend itself to explaining the pronounced right dominant strength asymmetry found in Neandertal humeri. In contrast, during the performance of all three unimanual scraping tasks, right side MAX and TOT were significantly greater at the AD (all values, p<.01) and PM (all values, p<.02) compared to the left. The consistency of the results provides evidence that scraping activities, such as hide preparation, may be a key behaviour in determining the unusual pattern of Neandertal arm morphology. Overall, these results yield important insight into the Neandertal behavioural repertoire that aided survival throughout Pleistocene Eurasia.     

Global late Quaternary megafauna extinctions linked to humans,not climate change

The late Quaternary megafauna extinction was a severe global-scale event. Two factors, climate change and modern humans, have received broad support as the primary drivers, but their absolute and relative importance remains controversial. To date, focus has been on the extinction chronology of individual or small groups of species, specific geographical regions or macroscale studies at very coarse geographical and taxonomic resolution, limiting the possibility of adequately testing the proposed hypotheses. We present, to our knowledge, the first global analysis of this extinction based on comprehensive country-level data on the geographical distribution of all large mammal species (more than or equal to 10 kg) that have gone globally or continentally extinct between the beginning of the Last Interglacial at 132 000 years BP and the late Holocene 1000 years BP, testing the relative roles played by glacial–interglacial climate change and humans. We show that the severity of extinction is strongly tied to hominin palaeobiogeography, with at most a weak, Eurasia-specific link to climate change. This first species-level macroscale analysis at relatively high geographical resolution provides strong support for modern humans as the primary driver of the worldwide megafauna losses during the late Quaternary.     

Apoptosis in cumulus cells, but not in oocytes, may influence bovine embryonic developmental competence

Aim of our study was to clarify if the occurrence of apoptosis in oocytes and cumulus cells is correlated to bovine oocyte developmental competence. The cumulus-oocyte complexes (COCs) were selected according to cumulus status: G1 with more than five layers of compact cumulus cells, G2 with one to five layers of compact cumulus cells and G3 with expanded cumulus cells. The degree of apoptosis in cumulus cells and oocytes measured by caspase staining and TUNEL assay before and after maturation, and 24 h post-insemination was compared to the cleavage, blastocyst formation and hatching rates of each group. Highest cleavage, blastocyst and hatching rates were found in cumulus-oocyte complexes with more than five layers of compact cumulus cells, but no apoptosis was detected in immature or in vitro matured oocytes, regardless of the cumulus status. Many cumulus cells contained active caspases before maturation, but caspase activity declined dramatically after maturation. TUNEL positive cells were rarely observed in each cumulus-oocyte complex upon oocyte recovery, but a huge increase of them was seen after in vitro maturation. Significantly more TUNEL and caspase positive cells were found in G2 cumulus-oocyte complexes. Our results suggest that: (i) oocyte apoptosis does not account for the inferior oocyte quality of G2 and G3; (ii) apoptosis occurs in cumulus cells regardless of the number and compactness of cumulus cells; and (iii) the degree of apoptosis in the compact cumulus-oocyte complexes (G1 and G2) is negatively correlated to the developmental competence of oocyte.     

The neotropical shrub Lupinus elegans,from temperate forests,may not adapt to climate change

Considering that their distribution is limited to altitudinal gradients along mountains that are likely to become warmer and drier, climate change poses an increased threat to temperate forest species from tropical regions. We studied whether the understorey shrub Lupinus elegans, endemic to temperate forests of west‐central Mexico, will be able to withstand the projected temperature increase under seven climate change scenarios. Seeds were collected along an altitudinal gradient and grown in a shade‐house over 7 months before determining their temperature tolerance as electrolyte leakage. The plants from colder sites tolerated lower temperatures, i.e. the temperature at which half of the maximum electrolyte leakage occurred (LT₅₀), ranged from −6.4 ± 0.7 to −2.4 ± 0.3 °C. In contrast, no pattern was found for tolerance to high temperature (LT₅₀ average 42.8 ± 0.3 °C). The climate change scenarios considered here consistently estimated an increase in air temperature during the present century that was higher for the maximum air temperature than for the mean or minimum. In particular, the anomaly from the normal maximum air temperature at the study region ranged from 2.8 °C by 2030 to 5.8 °C by 2090. In this respect, the inability of L. elegans to adapt to increasingly higher temperatures found here, in addition to a possible inhibition of reproduction caused by warmer winters, may limit its future distribution.     

Waveform dispersion, not reflection, may be the major determinant of aortic pressure wave morphology

The objective of this study was to investigate the determinants of aortic pressure waveform morphology in the thoracoabdominal aorta with specific reference to features of potential prognostic value for cardiovascular disease. In particular, we aimed to determine the location of major pressure wave reflection sites within the aorta. Aortic pressure waveforms were acquired with 2-Fr Millar Mikro-tip catheter transducers in 40 subjects (26 men, 14 women), and repeated in 10 subjects, at five predetermined points within the aorta: aortic root, transverse arch, and at the levels of the diaphragm, renal arteries, and aortic bifurcation. Waveforms were analyzed for augmentation index (AI), time to inflection point (Ti), and pressure parameters. AI decreased progressively between the aortic root and bifurcation (P < 0.001), and Ti increased (P < 0.01). There was the expected progressive peripheral amplification of systolic and pulse pressures and fall in time to peak pressure (all P < 0.001). There was no difference on repeat pullback or between sexes. These data are at variance with the concept that central AI results solely from pressure wave reflection, when Ti would be expected to decrease and AI increase with distal progression. Pressure wave propagation phenomena may contribute, and the potential role of frequency dispersion merits investigation.     

Cathepsin V, but not cathepsins L, B and K, may release angiostatin-like fragments from plasminogen

Abstract Cathepsin V is a lysosomal cysteine peptidase highly expressed in corneal epithelium; however, its function in the eye is still unknown. Here, we describe the capability of cathepsin V to hydrolyze plasminogen, which is also expressed in human cornea at levels high enough to produce physiologically relevant amounts of angiostatin-related molecules. The co-localization of these two proteins suggests an important role for the enzyme in the maintenance of corneal avascularity, essential for optimal visual performance. Sodium dodecyl sulfate-polyacrylamide gel electrophoretic analysis of plasminogen digestion by cathepsin V revealed the generation of three major products of 60, 50 and 40 kDa, which were electrotransferred to polyvinylidene difluoride membranes and excised for characterization. NH(2)-terminal amino acid sequencing of these fragments revealed the sequences EKKVYL, TEQLAP and LLPNVE, respectively. These data are compatible with cleavage sites at plasminogen F94-E95, S358-T359 and V468-L469 peptide bonds generating fragments of the five-kringle domains. In contrast, we did not detect any plasminogen degradation by cathepsins B, K and L. Using a Matrigel assay, we confirmed the angiogenesis inhibition activity on endothelial cells caused by plasminogen processing by cathepsin V. Our results suggest a novel physiological role for cathepsin V related to the control of neovascularization in cornea.     

Global sharing of COVID-19 vaccines: A duty of justice,not charity

Global scarcity of COVID-19 vaccines raises ethical questions about their fair allocation between nations. Section I introduces the question and proposes that wealthy nations have a duty of justice to share globally scarce COVID-19 vaccines. Section II distinguishes justice from charity and argues that beneficiaries of unjust structures incur duties of justice when they are systematically advantaged at others expense. Section III gives a case-based argument describing three upstream structural injustices that systematically advantaged wealthy countries and disadvantaged poorer countries, contributing to global disparities of COVID-19 vaccines. Section IV examines more closely the duties of justice owed, including a duty to relinquish holdings, restitute victims, and restore relationships. Section V concludes that wealthy nations have a duty of justice to share COVID-19 vaccines with poor nations and to restore relationships damaged by injustice. All nations should take steps to transform unjust structures.     

Females may not obtain indirect genetic benefits from extra-pair paternity in vinous-throated parrotbills, Paradoxornis webbianus

In birds, determining what females seek through extra-pair paternity (EPP) is fundamental in the understanding of variation in the incidence of EPP within and between species. I conducted genetic parentage analyses in vinous-throated parrotbills, Paradoxornis webbianus, a typical double-brooded passerine with a strong flock habit. In this species, it is known that the prevalence of EPP varies significantly between two egg-laying peaks; 95% of EPP occurred in the first peak. In the present study, I focused on whether or not females obtain genetic benefits through EPP and its relevance to the biased distribution of EPP between the two laying peaks. I found that females did not obtain ‘good genes’ so that extra-pair young were not better than within-pair young in terms of their body condition at the nestling stage or their survival rate to their first winter. I also found no significant effect of parental genetic similarity and local genetic diversity on the occurrence of EPP, and these genetic correlates were not related to the patchy distribution of EPP. Overall, this study concluded that female parrotbills may not pursue indirect benefits through EPP, and further study testing the possibility of direct benefits will be worthwhile.