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Abstract Background There is limited knowledge on how to increase soil organic carbon (SOC) stocks under tropical conditions. This study investigates SOC changes after converting land from native savanna (NS) to improved pasture (IP) land use. Methods Two acidic soil conversion sites were examined: (i) a poorly drained slope with medium‐texture soil (Casanare [CAS]1) and (ii) flat terrain with fine‐texture soil (CAS2). Another flat site was evaluated (Atlántico [ATL]), with fine‐textured to moderately textured neutral soil. Soil samples were collected and analyzed. SOC stocks (0–60 cm soil depth) were estimated, with a complex analysis of variance analyzing pasture type and soil depth. Results NS to IP conversion resulted in significant SOC accumulation in two regions, with losses in one (CAS2). ATL showed higher SOC accumulation than CAS. IP adoption led to SOC accumulation at depth (0–60 cm) after 10 years in CAS1. Elevated clay content in CAS2 favored SOC storage, while poorly drained areas hindered accumulation in CAS1. Cultivating rice before IP at CAS2 likely depleted SOC (0–20 cm), with 4 years of IP not restoring initial levels. Conclusions Adopting IP over NS can increase SOC. Grassland type, soil properties, and land‐use change all influence SOC accumulation. These data inform sustainable land management for low‐emission livestock production.

Abstract As climate change accelerates, understanding which species are most vulnerable and why they are vulnerable will be vital to inform conservation action. Climate change vulnerability assessments (CCVAs) are tools to assess species' responses to climate change, detect drivers of vulnerability, and inform conservation planning. CCVAs are commonly composed of three elements: exposure, sensitivity, and adaptive capacity. Incorporating all three elements can be challenging, and including only two of the three elements may be a more feasible approach in many systems. Although two‐element CCVA approaches have become more common, their utility and procedures remain poorly documented. We conducted a literature review to explore the scope, methods, and rationale of CCVAs that use a two‐element approach to assess vertebrate vulnerability. Despite the potential to expand CCVAs into understudied systems, two‐element assessments had similar geographic and taxonomic biases as those previously detected in CCVAs in general. Methods varied, yet we found that variables used in two‐element studies could be condensed into standardized categories to enhance comparability. Finally, limitations in data availability and computational resources were common rationales for using a two‐element approach. By clarifying the purposes, opportunities, and limitations of two‐element assessment, this review can aid in selecting appropriate methods for CCVAs.

Abstract The diverse range of patterns in porous media formed by dissolution processes depends on the relative magnitude of flow, transport, and chemical reactions at pore surfaces. However, distinguishing between regimes often relies solely on qualitative, visual comparisons of emergent structures. Here, we propose a quantitative measure capable of identifying different regimes using the concept of the spatial flow focusing profile, which segments the medium into cross sections along the flow direction to calculate the flow focusing index for each section. We employ this measure in numerical simulations of a dissolving porous medium using a pore network model. We obtain a morphological phase diagram of dissolution patterns, which we characterize using the flow focusing profile. In particular, we demonstrate that analyzing the temporal changes in the profile allows one to quantitatively distinguish between wormholing and channeling. The transition between them is shown to be affected by the heterogeneity of the system.

Abstract We perform a set of reactive transport simulations in three‐dimensional fracture networks to characterize the impact of geochemical reactions on flow channelization. Flow channelization, a frequently observed phenomenon in porous and fractured subsurface rock formations, results from the spatially variable hydraulic resistance offered by a geological structure. In addition to geo‐structural features such as network connectivity, geometry, and hydraulic resistance, geochemical reactions, for example, dissolution and precipitation, can dynamically inhibit or enhance flow channelization. These geochemical processes can change the fracture permeability leading to increased flow channelization, which are localized connected regions of high volumetric flow rates that are seemingly ubiquitous in the subsurface. In our simulations, fractures partially filled with quartz are gradually dissolved until quasi‐steady state conditions are obtained. We compare the flow field's initial unreacted and final dissolved states in terms of flow and transport observations. We observe that the dissolved fracture networks provide less resistance to flow and exhibit increased flow channelization when compared to their unreacted counterparts. However, there is substantial variability in the magnitude of these changes which implies that the channelization strongly depends on the network structure. In turn, we identify the interplay between the particular network structure and the impact of geochemical dissolution on flow channelization. The presented results indicate that geological systems that have been weathering or reactive for longer times in older landscapes are likely to have increased flow channelization compared to their equivalent but younger counterparts, which implies a time dependence on flow channelization in fractured media.

Abstract Background Medical mistrust, rooted in unethical research, is a barrier to cancer‐related health care for Black/African American (AA) persons. Understanding trust, mistrust, and health care experiences is crucial, especially in multiple myeloma (MM), which disproportionately burdens Black/AA persons in incidence and survival. Study Purpose This study qualitatively examines the experiences of Black/AA and White dyads (patient with MM and adult caregiver) to gain insights into these phenomena. Methods From November 2021 to April 2022, we recruited 21 dyads from the UNC Lineberger Comprehensive Cancer Center. Participants completed a sociodemographic survey and a 60–90 min semi‐structured interview. We used ATLAS.ti v9 for project management and to facilitate data analysis using the Sort and Sift, Think and Shift approach (ResearchTalk Inc). Results We interviewed 21 racially concordant dyads (11 Black/AA, 10 White) with mean patient ages of 70 (Black/AA) and 72 (White) at enrollment. Both Black/AA and White caregivers had a mean enrollment age of 68. The mean duration from MM diagnosis to enrollment for all patients was 5.5 years. Four key themes emerged: (1) knowledge and trust, (2) heightened emotions and discomfort, (3) differing mental constructs of health care experiences, and (4) mitigating mistrust, which varied by self‐identified race. Black/AA participants had greater knowledge of historical events like the U.S. Public Health Service Untreated Syphilis Study at Tuskegee and carried the emotional burden longer. They also emphasized self‐learning and self‐guided research about MM for informed medical decision‐making. Both Black/AA and White dyads emphasized the pivotal role of patient‐provider relationships and effective communication in fostering trust and addressing concerns. Conclusion Our study offers contextual insights into the enduring challenges of medical mistrust, particularly within the Black/AA community, and its implications for patients and caregivers accessing and receiving MM‐related care. Future studies should leverage these insights to guide the development of multilevel interventions addressing medical mistrust within the Black/AA community.

Abstract Objective Accumulation of misfolded superoxide dismutase‐1 (SOD1) is a pathological hallmark of SOD1‐related amyotrophic lateral sclerosis (ALS) and is observed in sporadic ALS where its role in pathogenesis is controversial. Understanding in vivo protein kinetics may clarify how SOD1 influences neurodegeneration and inform optimal dosing for therapies that lower SOD1 transcripts. Methods We employed stable isotope labeling paired with mass spectrometry to evaluate in vivo protein kinetics and concentration of soluble SOD1 in cerebrospinal fluid (CSF) of SOD1 mutation carriers, sporadic ALS participants and controls. A deaminated SOD1 peptide, SDGPVKV, that correlates with protein stability was also measured. Results In participants with heterozygous SOD1A5V mutations, known to cause rapidly progressive ALS, mutant SOD1 protein exhibited ~twofold faster turnover and ~ 16‐fold lower concentration compared to wild‐type SOD1 protein. SDGPVKV levels were increased in SOD1A5V carriers relative to controls. Thus, SOD1 mutations impact protein kinetics and stability. We applied this approach to sporadic ALS participants and found that SOD1 turnover, concentration, and SDGPVKV levels are not significantly different compared to controls. Interpretation These results highlight the ability of stable isotope labeling approaches and peptide deamidation to discern the influence of disease mutations on protein kinetics and stability and support implementation of this method to optimize clinical trial design of gene and molecular therapies for neurological disorders. Trial Registration Clinicaltrials.gov: NCT03449212.

Abstract The study of aging and neurodegenerative processes in the human brain requires a comprehensive understanding of cytoarchitectonic, myeloarchitectonic, and vascular structures. Recent computational advances have enabled volumetric reconstruction of the human brain using thousands of stained slices, however, tissue distortions and loss resulting from standard histological processing have hindered deformation‐free reconstruction. Here, the authors describe an integrated serial sectioning polarization‐sensitive optical coherence tomography (PSOCT) and two photon microscopy (2PM) system to provide label‐free multi‐contrast imaging of intact brain structures, including scattering, birefringence, and autofluorescence of human brain tissue. The authors demonstrate high‐throughput reconstruction of 4 × 4 × 2cm3 sample blocks and simple registration between PSOCT and 2PM images that enable comprehensive analysis of myelin content, vascular structure, and cellular information. The high‐resolution 2PM images provide microscopic validation and enrichment of the cellular information provided by the PSOCT optical properties on the same sample, revealing the densely packed fibers, capillaries, and lipofuscin‐filled cell bodies in the cortex and white matter. It is shown that the imaging system enables quantitative characterization of various pathological features in aging process, including myelin degradation, lipofuscin accumulation, and microvascular changes, which opens up numerous opportunities in the study of neurodegenerative diseases in the future.

Abstract We model flow and transport in fracture networks with varying degrees of fracture‐to‐fracture aperture heterogeneity and network intensity to show how changes in these properties can cause the emergence of anomalous flow and transport behavior. If fracture‐to‐fracture aperture heterogeneity is increased in sparse networks, velocity fluctuations inhibit high flow rates and solute transport can be delayed. Surprisingly, transport can be slowed even in cases where hydraulic aperture is monotonically increased. As the intensity of the networks is increased, more connected pathways allow for particles to bypass these effects. There exists transition behavior where with relatively few connected pathways in a network, first arrival times of particles are not heavily affected by fracture‐to‐fracture aperture heterogeneity, but the scaling behavior of the tails is strongly influenced. These results reinforce the importance of considering multi‐scale effects in fractured systems and can inform flow and transport processes in both natural and engineered fractured systems.

Abstract Background Cognitive difficulties have been described after chemotherapy for breast cancer, but there is no standard of care to improve cognitive outcomes in these patients. This trial examined the feasibility, tolerability, acceptability, and preliminary effects of memantine to prevent cognitive decline during chemotherapy for breast cancer. Methods Patients with stage I–III breast cancer, scheduled for neo/adjuvant chemotherapy, completed a cognitive battery prior to and 4 weeks after completing chemotherapy. Memantine (10 mg BID) was administered concurrent with chemotherapy. Our primary cognitive outcome was visual working memory assessed by the Delayed Matching to Sample test. We used the Brief Medication Questionnaire to assess acceptability. Results Of 126 patients approached, 56 (44%) enrolled. Forty‐five (80%) received ≥1 dose of memantine and completed pre‐post assessments. Seventy‐six percent reported taking ≥90% of scheduled doses. Participants were mean age of 56, 77% White, and 57% had stage I disease. Sixty‐four percent had stable or improved Delayed Matching to Sample test scores. Stable or improved cognition was observed in 87%–91% across objective cognitive domain composite measures. Sixty‐six percent self‐reported stable or improved cognitive symptoms. There were seven greater than or equal to grade 3 adverse events; two were possibly related to memantine. Only 5% reported that taking memantine was a disruption to their lives. Conclusions Memantine was well‐tolerated and consistently taken by a large majority of patients receiving breast cancer chemotherapy. The majority demonstrated stable or improved cognition from pre‐ to post‐assessment. Randomized trials are needed to determine memantine's efficacy to ameliorate cognitive loss. Trial Registration ClinicalTrials.gov NCT04033419.

Abstract Challenges facing societies around the globe as they plan for and adapt to climate change are so large that usable, research‐driven recommendations to inform management actions are urgently needed. We sought to understand factors that influence the variation of academic contribution and use of collaborative research on climate change. We surveyed researchers (n = 31), program‐leaders (n = 5), and stakeholders (n = 81) from projects supported by a federally funded network across the United States. Our results suggest that peer‐reviewed publications do not lead to use, but frequency of meetings with stakeholders significantly increased use. Overall, the factors needed for projects to have high degrees of academic contributions are distinct from those needed to be useful to stakeholders. Furthermore, leadership perceptions of use of projects were significantly different from users. Our quantitative results can inform future requests for proposals and better enable researchers using collaborative approaches to conduct science that is more often used by stakeholders.

Abstract Natural resource management involves balancing benefits and costs that accrue through time. How individuals and local communities weight such tradeoffs can profoundly influence how they use and conserve resources. Our goal was to understand time preferences of future benefits for goods that are relevant for developing effective conservation strategies. We surveyed >500 Fulani in Benin about their time preferences regarding financial, ecological, and agricultural goods, summarizing these in the form of discount rates. In a discrete‐time, constant annual form, our results were much higher (median: 150%) than values often discussed in literature. These discount rates declined through time; people valued the future more than would be assumed based on constant discounting. Discount rates were higher for financial goods than ecological or agricultural goods. We illustrate how our estimates of discount rates change recommendations for optimal management of forest resource harvesting in the tropics. While members of this grazing community discount future benefits at a high rate, they do so in ways that contrast with conventional economic theory and favor long‐term use of nontimber forest products.

Abstract Introduction Total tau (t‐tau) and phosphorylated tau (p‐tau) are abnormally elevated in the brain and cerebrospinal fluid of individuals with Alzheimer's disease (AD). Tau is also present in the salivary gland tissue and saliva, and salivary measures might produce an accurate, accessible, and inexpensive biomarker. Methods Using unstimulated saliva and Western blot analysis, we quantified the p‐tau/t‐tau ratio at different phosphorylation sites. Results We found that for one phosphorylation site, S396, p‐tau/t‐tau ratio was significantly elevated in patients with AD compared with normal elderly control subjects. The elevation in saliva, however, did not correlate with cerebrospinal fluid tau or with brain measures such as hippocampal volume. Discussion There is significant elevation of p‐tau/t‐tau ratio for the S396 phosphorylation site. Large variation in the AD salivary tau levels, however, limits the utility of this test as a clinical biomarker.

Abstract Introduction There is conflicting evidence whether high‐density lipoprotein cholesterol (HDL‐C) is a risk factor for Alzheimer's disease (AD) and dementia. Genetic variation in the cholesteryl ester transfer protein (CETP) locus is associated with altered HDL‐C. We aimed to assess AD risk by genetically predicted HDL‐C. Methods Ten single nucleotide polymorphisms within the CETP locus predicting HDL‐C were applied to the International Genomics of Alzheimer's Project (IGAP) exome chip stage 1 results in up 16,097 late onset AD cases and 18,077 cognitively normal elderly controls. We performed instrumental variables analysis using inverse variance weighting, weighted median, and MR‐Egger. Results Based on 10 single nucleotide polymorphisms distinctly predicting HDL‐C in the CETP locus, we found that HDL‐C was not associated with risk of AD (P > .7). Discussion Our study does not support the role of HDL‐C on risk of AD through HDL‐C altered by CETP. This study does not rule out other mechanisms by which HDL‐C affects risk of AD.