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A<sc>bstract</sc> In this work, we present a lattice QCD calculation of the Mellin moments of the twist-2 axial-vector generalized parton distribution (GPD),$$ \overset{\sim }{H}\left(x,\xi, t\right) $$ $\tilde{H}\left(x,\xi ,t\right)$, at zero skewness,ξ, with multiple values of the momentum transfer,t. Our analysis employs the short-distance factorization framework on ratio-scheme renormalized quasi-GPD matrix elements. The calculations are based on anN_f= 2 + 1 + 1 twisted mass fermions ensemble with clover improvement, a lattice spacing ofa= 0.093 fm, and a pion mass ofm_π= 260 MeV. We consider both the iso-vector and iso-scalar cases, utilizing next-to-leading-order perturbative matching while omitting the disconnected contributions and gluon mixing in the iso-scalar case. For the first time, we determine the Mellin moments of$$ \overset{\sim }{H} $$ $\tilde{H}$up to the fifth order. From these moments, we discuss the quark helicity and orbital angular momentum contributions to the nucleon spin, as well as the spin-orbit correlations of the quarks. Additionally, we perform a Fourier transform over the momentum transfer, which allows us to explore the spin structure in the impact-parameter space. 

ABSTRACT The Household Water Insecurity Experiences (HWISE) and Individual Water Insecurity Experiences (IWISE) Scales are globally suitable tools for comparably measuring water insecurity experiences among households and adults, respectively. The potential range for HWISE and IWISE scores is 0–36. When the WISE Scales were first published, scores of 12 and higher were considered indicative of water insecurity, but additional cut-points are needed to provide more nuanced insights. We therefore sought to develop a practical set of cut-points for the WISE Scales using HWISE data from 13 sites across 12 countries (n = 3,293) and nationally representative samples of IWISE data from 38 countries collected by the Gallup World Poll (n = 52,343). We selected cut-points in water insecurity scores to establish four ordinal categories: no-to-marginal (0–2), low (3–11), moderate (12–23), and high (24–36) water insecurity. These categories were monotonically associated with increasing odds of reporting water dissatisfaction and helped to differentiate the breadth of water insecurity across populations with heterogenous water insecurity experiences and frequencies. These four water insecurity categories can be used to better understand how water insecurity may be related to livelihoods, health, and well-being, both at low and high water insecurity. 

Traditional water indicators primarily focus on water quantity and quality, but emergent research demonstrates that measurement of lived experiences with water availability, accessibility, and use is important for understanding how household water insecurity impacts health and well-being. Few empirical studies have explored which household water insecurity experiences are most salient, or their potential causes, in Latin American cities. We analyzed data from 266 households in a low-income settlement of Cartagena, Colombia, to identify correlates and perceived determinants of water insecurity. The most prevalent household water insecurity experiences were water supply interruptions (96%), water worry (94%), and anger about the water situation (90%). Unexpected water interruptions and use of non-piped primary drinking water sources were associated with greater household water insecurity scores, water worry subscores, and hygiene subscores. Respondents perceived water issues in their community to be caused by deficiencies in gray infrastructure (49%), which included deficiencies in water distribution, treatment, or storage technologies. Social infrastructure (36%), including issues with political, economic, or administrative systems, was also cited as a barrier to water security. We did not detect significant relationships between water insecurity scores and the attribution of these problems to gray or social infrastructure, but there may be relationships between these factors and duration of residency and using a non-piped water source. These findings underscore the importance of socio-political factors and community engagement for improving urban water insecurity through slum-upgrade projects. 

Caribou ( Rangifer tarandus ) have among the longest annual migrations of any terrestrial mammal as they move from winter ranges to spring calving grounds. Biomonitoring records indicate broad consistencies in calving geography across the last several decades, but how long have herds used particular calving grounds? Furthermore, how representative are modern patterns of calving geography to periods that pre-date recent climatic perturbations and increased anthropogenic stresses? While modern ecological datasets are not long enough to address these questions, bones from past generations of caribou lying on the tundra provide unique opportunities to study historical calving geography. This is possible because female caribou shed their antlers within days of giving birth, releasing a skeletal indicator of calving. Today, the Coastal Plain of the Arctic National Wildlife Refuge (Alaska) is a key calving ground for the Porcupine Caribou Herd (PCH). To test the duration across which caribou have used this area as a calving ground, we radiocarbon dated three highly weathered female antlers collected from tundra surfaces on the Coastal Plain. Calibrated radiocarbon dates indicate that these antlers were shed between ~1,600 and more than 3,000 calendar years ago. The antiquity of these shed antlers provides the first physical evidence of calving activity on the PCH calving grounds from previous millennia, substantiating the long ecological legacy of the Coastal Plain as a caribou calving ground. Comparisons to published lake core records also reveal that dates of two of the antlers correspond to periods with average summer temperatures that were warmer than has been typical during the last several decades of biomonitoring. This finding expands the range of climatic settings in which caribou are known to use the current PCH calving grounds and suggests that the Coastal Plain of the Arctic Refuge may remain an important caribou calving ground during at least portions of predicted future warming. Discarded skeletal materials provide opportunities to assess the historical states of living populations, including aspects of reproductive biology and migration. Particularly in high-latitude settings, these insights can extend across millennia and offer rare glimpses into the past that can inform current and future management policies.