Plant hydraulic traits reveal islands as refugia from worsening drought.

Relatively mesic environments within arid regions may be important conservation targets as 'climate change refugia' for species persistence in the face of worsening drought conditions. Semi-arid southern California and the relatively mesic environments of California's Channel Islands provide a model system for examining drought responses of plants in potential climate change refugia. Most methods for detecting refugia are focused on 'exposure' of organisms to certain abiotic conditions, which fail to assess how local adaptation or acclimation of plant traits (i.e. 'sensitivity') contribute to or offset the benefits of reduced exposure. Here, we use a comparative plant hydraulics approach to characterize the vulnerability of plants to drought, providing a framework for identifying the locations and trait patterns that underlie functioning climate change refugia. Seasonal water relations, xylem hydraulic traits and remotely sensed vegetation indices of matched island and mainland field sites were used to compare the response of native plants from contrasting island and mainland sites to hotter droughts in the early 21st century. Island plants experienced more favorable water relations and resilience to recent drought. However, island plants displayed low plasticity/adaptation of hydraulic traits to local conditions, which indicates that relatively conserved traits of island plants underlie greater hydraulic safety and localized buffering from regional drought conditions. Our results provide an explanation for how California's Channel Islands function as a regional climate refugia during past and current climate change and demonstrate a physiology-based approach for detecting potential climate change refugia in other systems

Adaptation and acclimatization to ocean acidification in marine ectotherms: an in situ transplant experiment with polychaetes at a shallow CO₂ vent system

Metabolic rate determines the physiological and life-history performances of ectotherms. Thus, the extent to which such rates are sensitive and plastic to environmental perturbation is central to an organism's ability to function in a changing environment. Little is known of long-term metabolic plasticity and potential for metabolic adaptation in marine ectotherms exposed to elevated pCO₂. Consequently, we carried out a series of in situ transplant experiments using a number of tolerant and sensitive polychaete species living around a natural CO₂ vent system. Here, we show that a marine metazoan (i.e. Platynereis dumerilii) was able to adapt to chronic and elevated levels of pCO₂. The vent population of P. dumerilii was physiologically and genetically different from nearby populations that experience low pCO₂, as well as smaller in body size. By contrast, different populations of Amphiglena mediterranea showed marked physiological plasticity indicating that adaptation or acclimatization are both viable strategies for the successful colonization of elevated pCO₂ environments. In addition, sensitive species showed either a reduced or increased metabolism when exposed acutely to elevated pCO₂. Our findings may help explain, from a metabolic perspective, the occurrence of past mass extinction, as well as shed light on alternative pathways of resilience in species facing ongoing ocean acidification

Fictive Kinships and the Remaking of Family Life in the Context of Paid Domestic Work: The Case of Philippine \u3ci\u3eYayas\u3c/i\u3e

In this chapter, we draw from our study on Filipina rural-to-urban migrant workers in the domestic care sector to illustrate how migrants make and remake family in the context of separation. The setting of our study is in Quezon City, Philippines, and our participants are women employed as yayas-domestic care workers employed to care for children. They live in their employers\u27 homes, and most of our respondents live apart from their own children and all are living away from their nuclear families. Details of this study are laid out in an earlier paper that focused on the experience of family separation for domestic care workers and strategies they utilized to reconfigure and maintain relationships across physical distance (de Guzman, 2014). Here, we reexamine our data with a lens toward understanding how they rebuild new family life in their immediate contexts. We explore the nature of those relationships and how they reflect deeply embedded notions of family life (e.g., family roles) and implications for coping and wellbeing given the challenges of migration and domestic care work

Education sector risk assessment in the time of pandemic

The study explored school teachers, school administrators, and staff exposure to the COVID-19 virus in the workplace, the risk reduction practices of their organizations, organization response to those workers who were found positive of Coronavirus, and lastly the respondents’ suggestions to help their organization protect their employees. The study used a researcher-made risk assessment questionnaire, through Google Forms. The questionnaire was used in 25 selected respondent schools in the Philippines. The study revealed that the majority of the respondents were adopting the work from home, the rest of the respondents are reporting to school 1 up to 6 days a week. There are three major categories in handling the COVID-19 positive person such as implementation of health protocols, support to dimension of wellness, quick and immediate response. Moreover, the top three suggestions of the respondents are: i) Embrace new normal (appointments, enrolment, admission, and other transactions should be online); ii) Regularly provide vitamins, health kits, face masks, face shields, alcohol, and other medical supplies; iii) Provide training and webinars on health, safety training, mental health awareness, and online teaching.

A Repulsive Electrostatic Mechanism for Protein Export through the Type III Secretion Apparatus

This is the publisher's version. Copyright 2009 by Elsevier.Many Gram-negative bacteria initiate infections by injecting effector proteins into host cells through the type III secretion apparatus, which is comprised of a basal body, a needle, and a tip. The needle channel is formed by the assembly of a single needle protein. To explore the export mechanisms of MxiH needle protein through the needle of Shigella flexneri, an essential step during needle assembly, we have performed steered molecular dynamics simulations in implicit solvent. The trajectories reveal a screwlike rotation motion during the export of nativelike helix-turn-helix conformations. Interestingly, the channel interior with excessive electronegative potential creates an energy barrier for MxiH to enter the channel, whereas the same may facilitate the ejection of the effectors into host cells. Structurally known basal regions and ATPase underneath the basal region also have electronegative interiors. Effector proteins also have considerable electronegative potential patches on their surfaces. From these observations, we propose a repulsive electrostatic mechanism for protein translocation through the type III secretion apparatus. Based on this mechanism, the ATPase activity and/or proton motive force could be used to energize the protein translocation through these nanomachines. A similar mechanism may be applicable to macromolecular channels in other secretion systems or viruses through which proteins or nucleic acids are transported

Identification of the MxiH Needle Protein Residues Responsible for Anchoring Invasion Plasmid Antigen D to the Type III Secretion Needle Tip

The pathogenesis of Shigella flexneri requires a functional type III secretion apparatus to serve as a conduit for injecting host-altering effector proteins into the membrane and cytoplasm of the targeted cell. The type III secretion apparatus is composed of a basal body and an exposed needle that is an extended polymer of MxiH with a 2.0-nm inner channel. Invasion plasmid antigen D (IpaD) resides at the tip of the needle to control type III secretion. The atomic structures of MxiH and IpaD have been solved. MxiH (8.3 kDa) is a helix-turn-helix, whereas IpaD (36.6 kDa) has a dumbbell shape with two globular domains flanking a central coiled-coil that stabilizes the protein. These structures alone, however, have not been sufficient to produce a workable in silico model by which IpaD docks at the needle tip. Thus, the work presented here provides an initial step in understanding this important protein-protein interaction. We have identified key MxiH residues located in its PSNP loop and the contiguous surface that uniquely contribute to the formation of the IpaD-needle interface as determined by NMR chemical shift mapping. Mutation of Asn-43, Leu-47, and Tyr-50 residues severely affects the stable maintenance of IpaD at the Shigella surface and thus compromises the invasive phenotype of S. flexneri. Other residues could be mutated to give rise to intermediate phenotypes, suggesting they have a role in tip complex stabilization while not being essential for tip complex formation. Initial in vitro fluorescence polarization studies confirmed that specific amino acid changes adversely affect the MxiH-IpaD interaction. Meanwhile, none of the mutations appeared to have a negative effect on the MxiH-MxiH interactions required for efficient needle assembly

Involucrin modulates vitamin D receptor activity in the epidermis

Terminally differentiated keratinocytes are critical for epidermal function and are surrounded by involucrin (IVL). Increased IVL expression is associated with a near-selective sweep in European populations compared with those in Africa. This positive selection for increased IVL in the epidermis identifies human adaptation outside of Africa. The functional significance is unclear. We hypothesize that IVL modulates the environmentally sensitive vitamin D receptor (VDR) in the epidermis. We investigated VDR activity in Iv

The anti-depressant and anxiolytic properties of the lyophilized aqueous leaf extract of Mimosa pudica L. (Fabaceae)

Introduction: This study seeks to determine the antidepressant and anxiolytic properties of the lyophilized aqueous leaf extract of Mimosa pudica (LAL-MP) in mice. Methods: LAL-MP was administered orally to mice at 50 – 500 mg/kg, daily for 14 days, after which mice were individually subjected to the forced swimming (FST) and tail suspension (TST) tests, the elevated plus maze (EPM) model and locomotor activity count. Results: Generally, LAL-MP from 100 to 500 mg/kg exhibit antidepressant and anxiolytic properties in all 4 models of depression and dose levels at 400 and 500 mg/kg were found to be equipotent with the standard drug fluoxetine. Conclusions: This is the first report on the combined antidepressant and anxiolytic properties of LAL-MP

Comparative In Vitro Dissolution Profile of Commercial Azithromycin Dihydrate 500 mg Tablet Preparations in the Philipppines

This study seeks to compare the in vitro multi-point dissolution profiles between 3 off-patent products azithromycin dihydrate 500 mg and the innovator product. The paddle-type dissolution apparatus was used. This was rotated at a speed of 50 rpm using 0.1-N HCl as media. Random samples were withdrawn after certain time points and assayed for azithromycin dihydrate. Comparision between test samples and the innovator product was done by computing their similarity (f 1 ) and disimilarity (f 2 ) factors and by fitting them to various kinetics of drug release during dissolution. Test samples 1 and 3 were comparable to the innovator product because they complied with f 1 and f 2 specifications. Test sample 2, however, gave higher f 2 values making it non-equivalent with the innovator product. The Higuchi and Korsmeyer-Peppa kinetics of drug release characterized most of the dissolution profiles. This study showed that test samples 1 and 3 are equivalent with the innovator products in terms of comparative in vitro dissolution profiles where extra-Fickian release behaviors was exhibited by all the preparations