Flexible resource use strategies of a central-place forager experiencing dynamic risk and opportunity

We used data collected from GPS loggers on golden-mantled ground squirrels (Callospermophilus lateralis) to model selection or avoidance of resources in two seasons of seed availability and one season in which no seeds were available. Movement decisions were measured in short-term discrete time intervals using high resolution location data. Selection or avoidance of specific resource features that entail fitness consequences were then assessed using resource selection functions.University of Nevada, Reno, Whittell Forest Graduate Fellowship endowed fundOpen access journalThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

Toward a feminist political ecology of household food and water security during drought in northern Nicaragua

Few studies assess the relationship between food and water access, despite global concerns about people’s inability to maintain access to both food and water. We conducted a mixed-methods comparative case study in northern Nicaragua, with smallholders from two neighboring communities that differed in water availability and institutional strength, using a feminist political ecology framework and food and water security definitions that focus on access, availability, use, and stability. We adopted a participatory approach that included: a sex-disaggregated survey in 2016; interviews, participant observation, and community-based water quality testing from 2014 to 2019; and analysis of a severe drought that occurred from 2014 to 2017. Our results suggest that uneven power relations, biophysical conditions, gender, and institutions shape food and water access, and indicate that households across both communities average 2 months of drinking water insecurity during the dry season followed by an average of 2.5 months of food insecurity early in the growing season. The average duration of lean food months was similar across communities and sex, but water insecurity lasted longer in the community that had weaker local institutions and less surface water availability. Ethnographic research helped to document uneven and gendered experiences of water access and to illustrate how they were also shaped by conflicts over water for irrigation vs. domestic uses and cross-scalar limitations in water and land governance. Although we found that gender and institutions were not strong predictors of several food and water insecurity indicators on their own, both factors influenced the terms of access, conflict, and cooperative governance needed to secure resources and well-being. Our study highlights the need for theory, methods, and field research that integrate the analysis of food and water security, and it contributes to developing a feminist political ecology approach that unifies this analysis with a focus on gender

Work and Family Variables as Related to Paternal Engagement, Responsibility, and Accessibility in Dual-Earner Couples with Young Children

Fathers and mothers (N = 75 dual-earner couples) of preschool-aged children completed questionnaires that examined work and family variables as related to paternal involvement in three areas: engagement (i.e., directly interacting with the child), responsibility (i.e., scheduling activities and being accountable for the child\u27s well-being), and accessibility (i.e., being available to the child but not in direct interaction). Fathers\u27 reports of responsibility and accessibility were significantly predicted by structural variables and beliefs; however, fathers\u27 reports of engagement were not predicted by work and family variables. Mothers\u27 reports of work and family variables did not predict their reports of father involvement. These findings suggest that for fathers of young children, parental involvement appears mainly self-determined

Identification of source-sink dynamics in mountain lions of the Great Basin

Natural and anthropogenic boundaries have been shown to affect population dynamics and population structure for many species with movement patterns at the landscape level. Understanding population boundaries and movement rates in the field for species that are cryptic and occur at low densities is often extremely difficult and logistically prohibitive; however genetic techniques may offer insights that have previously been unattainable. We analyzed thirteen microsatellite loci for 739 mountain lions (Puma concolor) using muscle tissue samples from individuals in the Great Basin throughout Nevada and the Sierra Nevada mountain range to test the hypothesis that heterogeneous hunting pressure results in source-sink dynamics at the landscape scale. We used a combination of non-spatial and spatial model-based Bayesian clustering methods to identify genetic populations. We then used a recently developed Bayesian multilocus genotyping method to estimate asymmetrical rates of contemporary movement between those subpopulations and to identify source and sink populations. We identified two populations at the highest level of genetic structuring with a total of five subpopulations in the Great Basin of Nevada and the Sierra Nevada range. Our results suggest that source-sink dynamics occur at landscape scales for wide-ranging species, such as mountain lions, and that source populations may be those that are under relatively less hunting pressure and that occupy refugia

Mitochondria-Penetrating Peptides

SummaryMitochondria are important targets for cancer chemotherapy and other disease treatments. Gaining access to this organelle can be difficult, as the inner membrane is a barrier limiting diffusive transport. A mitochondrial molecular carrier would be a boon to the development of organelle-specific therapeutics. Here, we report a significant advance in the development of mitochondrial transporters—synthetic cell-permeable peptides that are able to enter mitochondria. Efficient uptake of these mitochondria-penetrating peptides (MPPs) is observed in a variety of cell types, and organellar specificity is attained with sequences that possess specific chemical properties. The MPPs identified are cationic, but also lipophilic; this combination of characteristics facilitates permeation of the hydrophobic mitochondrial membrane. The examination of a panel of MPPs illustrates that mitochondrial localization can be rationally controlled and finely tuned by altering lipophilicity and charge

Towards smallholder food and water security: Climate variability in the context of multiple livelihood hazards in Nicaragua

Climate variability and change affect both food and water security, as do other hazards, such as shifting food prices, plant pathogens, and political economic changes. Although household food and water insecurity affect billions, most studies analyze them separately. This article develops a relational approach to explaining household access to food and water in a multi-hazard context. We identify pathways linking hazards to livelihood vulnerability and assess the relative importance of climate-related hazards. Analyzing longitudinal data collected from two surveys of the same 311 smallholder households in northern Nicaragua, conducted in 2014 and again in 2017, we find that peak seasons of food and water stress are asynchronous across the agricultural calendar, resulting in a total of five to six months of food and/or water stress. Across households, we find a significant positive relationship between water and food insecurity, even after adjusting for household fixed effects. Households experienced less food and water insecurity in 2017 than in 2014, due in part to the end of a severe drought in 2016, but remained concerned about damage from a severe coffee leaf rust outbreak and unfavorable agrifood prices that reduce income and threaten food security. Higher incomes and larger farm areas correlated with improved food and water security. We propose a generalizable approach for the joint assessment of household food and water security, which foregrounds the influence of seasonality and climate variability in the context of multiple hazards. This approach and our findings can contribute to developing integrated risk reduction strategies, building resilient livelihoods, and informing policy changes and partnerships with organized smallholders to improve resource access and sovereignty

Non-global Structure of the O({\alpha}_s^2) Dijet Soft Function

High energy scattering processes involving jets generically involve matrix elements of light- like Wilson lines, known as soft functions. These describe the structure of soft contributions to observables and encode color and kinematic correlations between jets. We compute the dijet soft function to O({\alpha}_s^2) as a function of the two jet invariant masses, focusing on terms not determined by its renormalization group evolution that have a non-separable dependence on these masses. Our results include non-global single and double logarithms, and analytic results for the full set of non-logarithmic contributions as well. Using a recent result for the thrust constant, we present the complete O({\alpha}_s^2) soft function for dijet production in both position and momentum space.Comment: 55 pages, 8 figures. v2: extended discussion of double logs in the hard regime. v3: minor typos corrected, version published in JHEP. v4: typos in Eq. (3.33), (3.39), (3.43) corrected; this does not affect the main result, numerical results, or conclusion

Novel mutations in TARDBP (TDP-43) in patients with familial amyotrophic lateral sclerosis.

The TAR DNA-binding protein 43 (TDP-43) has been identified as the major disease protein in amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration with ubiquitin inclusions (FTLD-U), defining a novel class of neurodegenerative conditions: the TDP-43 proteinopathies. The first pathogenic mutations in the gene encoding TDP-43 (TARDBP) were recently reported in familial and sporadic ALS patients, supporting a direct role for TDP-43 in neurodegeneration. In this study, we report the identification and functional analyses of two novel and one known mutation in TARDBP that we identified as a result of extensive mutation analyses in a cohort of 296 patients with variable neurodegenerative diseases associated with TDP-43 histopathology. Three different heterozygous missense mutations in exon 6 of TARDBP (p.M337V, p.N345K, and p.I383V) were identified in the analysis of 92 familial ALS patients (3.3%), while no mutations were detected in 24 patients with sporadic ALS or 180 patients with other TDP-43-positive neurodegenerative diseases. The presence of p.M337V, p.N345K, and p.I383V was excluded in 825 controls and 652 additional sporadic ALS patients. All three mutations affect highly conserved amino acid residues in the C-terminal part of TDP-43 known to be involved in protein-protein interactions. Biochemical analysis of TDP-43 in ALS patient cell lines revealed a substantial increase in caspase cleaved fragments, including the approximately 25 kDa fragment, compared to control cell lines. Our findings support TARDBP mutations as a cause of ALS. Based on the specific C-terminal location of the mutations and the accumulation of a smaller C-terminal fragment, we speculate that TARDBP mutations may cause a toxic gain of function through novel protein interactions or intracellular accumulation of TDP-43 fragments leading to apoptosis

Variation in diet of desert bighorn sheep (Ovis canadensis nelsoni): Tradeoffs associated with parturition

Selection of forage and habitats is driven by nutritional needs of individuals. Some species may sacrifice nutritional quality of forage for the mother in favor of safety of offspring (risk-averse strategy), immediately following parturition. We studied diet quality and forage selection by bighorn sheep before and following parturition to determine how nutritional demands associated with rearing offspring influenced forage acquisition. We used desert bighorn sheep, Ovis canadensis nelsoni, to investigate that potential tradeoff. We captured and radio-collared female bighorn sheep from 2016 to 2018. We used vaginal implant transmitters (VIT)s in pregnant females to identify parturition and to capture and radio-collar neonates to monitor survival of young. We collected fecal samples throughout the breeding season and throughout the year to understand diet quality and composition throughout those temporal periods. We determined diet quality and composition for pre-parturient females, females provisioning offspring, females that lost offspring, and non-pregnant individuals using fecal nitrogen and DNA metabarcoding analyses. Additionally, we compared the diet quality and composition of offspring and adult females during the spring, as well as summer and winter months. Our results indicated differences in diet quality between individuals provisioning offspring and those whose offspring had died. Females that were provisioning dependent young had lower quality diets than those that lost their offspring. Diet composition among those groups was also markedly different; females that had lost an offspring had a more diverse diet than did females with dependent young. Diet quality differed among seasons, wherein offspring and adult females had higher quality diets during the spring months, with decreasing quality as the year progressed. Diet diversity was similar across seasons, although spring months tended to be most diverse. Our results support tradeoffs associated with risk-averse strategies made by adult females associated with parturition. Nutritional quality of forage was linked to provisioning status, indicating that females were trading diet quality for safety of offspring, but those females whose offspring had died selected high quality forages. Those results help explain habitat selection observed in mountain ungulates around parturition and provide further insight into the evolutionary processes and adaptive significance exhibited by those specialized artiodactyls