Extending the Osmometer Method for Assessing Drought Tolerance in Herbaceous Species

Community-scale surveys of plant drought tolerance are essential for understanding semi-arid ecosystems and community responses to climate change. Thus, there is a need for an accurate and rapid methodology for assessing drought tolerance strategies across plant functional types. The osmometer method for predicting leaf osmotic potential at full turgor ((o)), a key metric of leaf-level drought tolerance, has resulted in a 50-fold increase in the measurement speed of this trait; however, the applicability of this method has only been tested in woody species and crops. Here, we assess the osmometer method for use in herbaceous grassland species and test whether (o) is an appropriate plant trait for understanding drought strategies of herbaceous species as well as species distributions along climate gradients. Our model for predicting leaf turgor loss point ((TLP)) from (o) ((TLP)=0.80(o)-0.845) is nearly identical to the model previously presented for woody species. Additionally, (o) was highly correlated with (TLP) for graminoid species ((tlp)=0.944(o)-0.611; r(2)=0.96), a plant functional group previously flagged for having the potential to cause erroneous measurements when using an osmometer. We report that (o), measured with an osmometer, is well correlated with other traits linked to drought tolerance (namely, leaf dry matter content and leaf vulnerability to hydraulic failure) as well as climate extremes linked to water availability. The validation of the osmometer method in an herb-dominated ecosystem paves the way for rapid community-scale surveys of drought tolerance across plant functional groups, which could improve trait-based predictions of ecosystem responses to climate change

Changing impacts of Alaska-Aleutian subduction zone tsunamis in California under future sea-level rise

The amplification of coastal hazards such as distant-source tsunamis under future relative sea-level rise (RSLR) is poorly constrained. In southern California, the Alaska-Aleutian subduction zone has been identified as an earthquake source region of particular concern for a worst-case scenario distant-source tsunami. Here, we explore how RSLR over the next century will influence future maximum nearshore tsunami heights (MNTH) at the Ports of Los Angeles and Long Beach. Earthquake and tsunami modeling combined with local probabilistic RSLR projections show the increased potential for more frequent, relatively low magnitude earthquakes to produce distant-source tsunamis that exceed historically observed MNTH. By 2100, under RSLR projections for a high-emissions representative concentration pathway (RCP8.5), the earthquake magnitude required to produce \u3e1 m MNTH falls from ~Mw9.1 (required today) to Mw8.0, a magnitude that is ~6.7 times more frequent along the Alaska-Aleutian subduction zone

Qualitative Analysis of String Cosmologies

A qualitative analysis is presented for spatially flat, isotropic and homogeneous cosmologies derived from the string effective action when the combined effects of a dilaton, modulus, two-form potential and central charge deficit are included. The latter has significant effects on the qualitative dynamics. The analysis is also directly applicable to the anisotropic Bianchi type I cosmology.Comment: 13 pages, 4 postscript figures, accepted to Physical Review

Anatomy of ethylene-induced floral-organ abscission in Chamelaucium uncinatum (Myrtaceae)

Postharvest abscission of Geraldton waxflower (Chamelaucium uncinatum Schauer) flower buds and flowers is ethylene-mediated. Exposure of floral organs to exogenous ethylene (1 mu L L-1) for 6 h at 20 degrees C induced separation at a morphologically and anatomically distinct abscission zone between the pedicel and. oral tube. Flower buds with opening petals and flowers with a nectiferous hypanthium were generally more responsive to exogenous ethylene than were flower buds enclosed in shiny bracteoles and aged (senescing) flowers. The anatomy of abscission-zone cells did not change at sequential stages of floral development from immature buds to aged flowers. The zone comprised a layer of small, laterally elongated-to-rounded, closely packed and highly protoplasmic parenchyma cells. Abscission occurred at a two- to four-cell-wide separation layer within the abscission zone. The process involved degradation of the middle lamella between separation layer cells. Following abscission, cells on both the proximal and distal faces of the separation layer became spherical, loosely packed and contained degenerating protoplasm. Central vascular tissues within the surrounding band of separation layer cells became torn and fractured. For flower buds, bracteoles that enclose the immature floral tube also separated at an abscission zone. However, this secondary abscission zone appeared less sensitive to ethylene than the primary ( central). oral-tube abscission zone as bracteoles generally only completely abscised when exposed to 10 mu L L-1 ethylene for the longer period of 24 h at 20 degrees C. The smooth surfaces of abscised separation-layer cells suggest that hydrolase enzymes degrade the middle lamella between adjacent cell walls

Association between patient activation, self-management behaviours and clinical outcomes in adults with diabetes or related metabolic disorders: a systematic review and meta-analysis protocol.

INTRODUCTION: Diabetes and related metabolic disorders such as obesity and cardiovascular diseases (CVD) are a growing global issue. Equipping individuals with the necessary 'knowledge, skills and confidence to self-manage their health' (ie, patient activation (PAct)) may lead to improvements in health outcomes. It is unclear whether existing evidence allows us to assume a causal relationship. We aim to synthesise and critically appraise evidence on the relationship between PAct and self-management behaviours and clinical outcomes of people living with diabetes and related metabolic disorders. METHODS AND ANALYSIS: The protocol is based on guidance on Preferred Reporting Items for Systematic Review and Meta-analysis Protocols. We will search Medline, Embase, CENTRAL, PsycInfo, Web of Science and CINAHL using search terms related to PAct, diabetes, pre-diabetes, obesity and CVD. Any quantitative study design is eligible provided studies assess the association between PAct and clinical outcomes and/or self-management behaviours of diabetes and related metabolic disorders. Outcomes include behavioural (eg, diet) and clinical (eg, blood pressure) outcomes. Two reviewers will independently screen titles/abstracts and full texts and assess risk of bias using the revised Cochrane risk-of-bias tool for randomised trials or the Risk of Bias Assessment Tool for Nonrandomised Studies (RoBANS).One reviewer will extract data, with independent checking by a second reviewer. We will critically assess the level of evidence available for assuming a causal association between PAct and outcomes. Data permitting, we will use the Hunter-Schmidt random-effects method to meta-analyse correlations across studies. ETHICS AND DISSEMINATION: Ethical approval is not required. The review will be disseminated in the form of a peer-reviewed journal article, at conferences and other presentations. The findings of the review will be of interest to clinical commissioning groups, policymakers and intervention deliverers/developers. PROSPERO REGISTRATION NUMBER: CRD42021230727

Evidence for a Proton–Protein Symport Mechanism in the Anthrax Toxin Channel

The toxin produced by Bacillus anthracis, the causative agent of anthrax, is composed of three proteins: a translocase heptameric channel, (PA63)7, formed from protective antigen (PA), which allows the other two proteins, lethal and edema factors (LF and EF), to translocate across a host cell's endosomal membrane, disrupting cellular homeostasis. It has been shown that (PA63)7 incorporated into planar phospholipid bilayer membranes forms a channel capable of transporting LF and EF. Protein translocation through the channel is driven by a proton electrochemical potential gradient on a time scale of seconds. A paradoxical aspect of this is that although LFN (the N-terminal 263 residues of LF), on which most of our experiments were performed, has a net negative charge, it is driven through the channel by a cis-positive voltage. We have explained this by claiming that the (PA63)7 channel strongly disfavors the entry of negatively charged residues on proteins to be translocated, and hence the aspartates and glutamates on LFN enter protonated (i.e., neutralized). Therefore, the translocated species is positively charged. Upon exiting the channel, the protons that were picked up from the cis solution are released into the trans solution, thereby making this a proton–protein symporter. Here, we provide further evidence of such a mechanism by showing that if only one SO3−, which is essentially not titratable, is introduced at most positions in LFN, through the reaction of an introduced cysteine residue at those positions with 2-sulfonato-ethyl-methanethiosulfonate, voltage-driven LFN translocation is drastically inhibited. We also find that a site that disfavors the entry of negatively charged residues into the (PA63)7 channel resides at or near its Φ-clamp, the ring of seven phenylalanines near the channel's entrance

Shifts in Plant Functional Composition Following Long-term Drought in Grasslands

1. Plant traits can provide unique insights into plant performance at the community scale. Functional composition, defined by both functional diversity and community-weighted trait means (CWMs), can affect the stability of above-ground net primary production (ANPP) in response to climate extremes. Further complexity arises, however, when functional composition itself responds to environmental change. The duration of climate extremes, such as drought, is expected to increase with rising global temperatures; thus, understanding the impacts of long-term drought on functional composition and the corresponding effect that has on ecosystem function could improve predictions of ecosystem sensitivity to climate change. 2. We experimentally reduced growing season precipitation by 66% across six temperate grasslands for 4 years and measured changes in three indices of functional diversity (functional dispersion, richness and evenness), community-weighted trait means and phylogenetic diversity (PD). Specific leaf area (SLA), leaf nitrogen content (LNC) and (at most sites) leaf turgor loss point (pi(TLP)) were measured for species cumulatively representing similar to 90% plant cover at each site. 3. Long-term drought led to increased community functional dispersion in three sites, with negligible effects on the remaining sites. Species re-ordering following the mortality/senescence of dominant species was the main driver of increased functional dispersion. The response of functional diversity was not consistently matched by changes in phylogenetic diversity. Community-level drought strategies (assessed as CWMs) largely shifted from drought tolerance to drought avoidance and/or escape strategies, as evidenced by higher community-weighted pi(TLP), SLA and LNC. Lastly, ecosystem drought sensitivity (i.e. relative reduction in ANPP in drought plots) was positively correlated with community-weighted SLA and negatively correlated with functional diversity. 4. Synthesis. Increased functional diversity following long-term drought may stabilize ecosystem functioning in response to future drought. However, shifts in community-scale drought strategies may increase ecosystem drought sensitivity, depending on the nature and timing of drought. Thus, our results highlight the importance of considering both functional diversity and abundance-weighted traits means of plant communities as their collective effect may either stabilize or enhance ecosystem sensitivity to drought

Ablation of β1 integrin in mammary epithelium reveals a key role for integrin in glandular morphogenesis and differentiation

Integrin-mediated adhesion regulates the development and function of a range of tissues; however, little is known about its role in glandular epithelium. To assess the contribution of β1 integrin, we conditionally deleted its gene in luminal epithelia during different stages of mouse mammary gland development and in cultured primary mammary epithelia. Loss of β1 integrin in vivo resulted in impaired alveologenesis and lactation. Cultured β1 integrin–null cells displayed abnormal focal adhesion function and signal transduction and could not form or maintain polarized acini. In vivo, epithelial cells became detached from the extracellular matrix but remained associated with each other and did not undergo overt apoptosis. β1 integrin–null mammary epithelial cells did not differentiate in response to prolactin stimulation because of defective Stat5 activation. In mice where β1 integrin was deleted after the initiation of differentiation, fewer defects in alveolar morphology occurred, yet major deficiencies were also observed in milk protein and milk fat production and Stat5 activation, indicating a permissive role for β1 integrins in prolactin signaling. This study demonstrates that β1 integrin is critical for the alveolar morphogenesis of a glandular epithelium and for maintenance of its differentiated function. Moreover, it provides genetic evidence for the cooperation between integrin and cytokine signaling pathways

Expert Panel Recommendations on Lower Urinary Tract Health of Women Across Their Life Span

Urologic and kidney problems are common in women across their life span and affect their daily life, including physical activity, sexual relations, social life, and future health. Urological health in women is still understudied and the underlying mechanisms of female urological dysfunctions are not fully understood. The Society for Women's Health Research (SWHR?) recognized the need to have a roundtable discussion where researchers and clinicians would define the current state of knowledge, gaps, and recommendations for future research directions to transform women's urological health. This report summarizes the discussions, which focused on epidemiology, clinical presentation, basic science, prevention strategies, and efficacy of current therapies. Experts around the table agreed on a set of research, education, and policy recommendations that have the potential to dramatically increase awareness and improve women's urological health at all stages of life.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/140146/1/jwh.2016.5895.pd