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Numerous studies have shown reduced performance in plants that are surrounded by neighbours of the same species1,2, a phenomenon known as conspecific negative density dependence (CNDD)3. A long-held ecological hypothesis posits that CNDD is more pronounced in tropical than in temperate forests4,5, which increases community stabilization, species coexistence and the diversity of local tree species6,7. Previous analyses supporting such a latitudinal gradient in CNDD8,9 have suffered from methodological limitations related to the use of static data10-12. Here we present a comprehensive assessment of latitudinal CNDD patterns using dynamic mortality data to estimate species-site-specific CNDD across 23 sites. Averaged across species, we found that stabilizing CNDD was present at all except one site, but that average stabilizing CNDD was not stronger toward the tropics. However, in tropical tree communities, rare and intermediate abundant species experienced stronger stabilizing CNDD than did common species. This pattern was absent in temperate forests, which suggests that CNDD influences species abundances more strongly in tropical forests than it does in temperate ones13. We also found that interspecific variation in CNDD, which might attenuate its stabilizing effect on species diversity14,15, was high but not significantly different across latitudes. Although the consequences of these patterns for latitudinal diversity gradients are difficult to evaluate, we speculate that a more effective regulation of population abundances could translate into greater stabilization of tropical tree communities and thus contribute to the high local diversity of tropical forests.

Plant‐mycorrhizal type has been suggested as an integrator of plant functional traits, yet most of what is known about these relationships comes from studies of different plant taxa, where the effects of mycorrhizal type cannot be isolated. In addition to affecting carbon‐nutrient exchanges, plants that associate with distinct mycorrhizal types often differ in several traits, with consequences for myriad below‐ground processes.We used two common gardens planted with Populus fremontii, a tree species that can simultaneously associate with both arbuscular mycorrhizal (AM) and ectomycorrhizal (ECM) fungi, to examine the degree to which mycorrhizal‐type dominance influences root traits and trait relationships across the root economic space.While P. fremontii formed AM and ECM associations simultaneously, individuals displayed a dominant mycorrhizal type driven primarily by garden location. Trees in the low‐elevation garden, regardless of provenance, were colonized primarily by AM fungi, whereas trees in the high‐elevation garden were colonized primarily by ECM fungi. In root systems at the low‐elevation garden, AM colonization rates were negatively related to specific root length indicating trade‐off with investment in foraging roots. In contrast, root systems at the high‐elevation garden, ECM colonization was negatively related to root tissue density, demonstrating a potential trade‐off between resource acquisition and root growth/defence. All other root economic traits remained similar between mycorrhizal types.While root traits varied little between AM‐ and ECM‐dominated trees (and gardens), their relationships with one another differed in each garden, suggesting unique strategies and trait trade‐offs in a single species. As global change continues to alter environments, species like P. fremontii, which experience a range of abiotic conditions, could signal how other tree species might modify root traits and strategies in response. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

The growing interest in bamboo fibers for pulp, paper, and board production in the USA necessitates a comprehensive financial viability assessment. This study conducts a detailed technoeconomic analysis (TEA) of bamboo fiber production, primarily for the consumer hygiene tissue market although it is also applicable to other industrial uses. The economic viability of two pulping methods – alkaline peroxide mechanical pulping (APMP) and ammonium bisulfite chemical pulping (ABS) – was explored within three different pulp mill settings to supply pulp to two nonintegrated tissue and towel mills in South Carolina, USA. The target was to produce wet lap bamboo bleached pulp at 50% consistency and 70% ISO brightness. Despite higher initial capital invesment and operating costs, ABS achieved a lower minimum required selling price – USD 544 to 686 per bone dry metric ton (BDt = 1000 BDkg) – in comparison with USD 766 to 899 BDt−1 for APMP. This price advantage is partly due to an additional revenue stream (lignosulfonate byproduct), which not only boosts revenue but also circumvents the need for expensive chemical recovery systems. When compared with traditional kraft pulping, both methods require significantly lower capital investments, with minimum required selling prices (estimated to achieve 16% IRR) below current market rates for extensively used bleached kraft pulps in the USA tissue industry. The economic benefits derive from several factors: the low cost of bamboo as raw material, reduced capital needs for new pulping technologies, lower transportation costs from the pulp mill to tissue and towel manufacturing facilities, and the high market price of bleached kraft pulp. [ABSTRACT FROM AUTHOR]

Forests around the world are experiencing changes due to climate variability and human land use. How these changes interact and influence the vulnerability of forests are not well understood. In the eastern United States, well‐documented anthropogenic disturbances and land‐use decisions, such as logging and fire suppression, have influenced forest species assemblages, leading to a demographic shift from forests dominated by xeric species to those dominated by mesic species. Contemporarily, the climate has changed and is expected to continue to warm and produce higher evaporative demand, imposing stronger drought stress on forest communities. Here, we use an extensive network of tree‐ring records from common hardwood species across ~100 sites and ~1300 trees in the eastern United States to examine the magnitude of growth response to both wet and dry climate extremes. We find that growth reductions during drought exceed the positive growth response to pluvials. Mesic species such as Liriodendron tulipifera and Acer saccharum, which are becoming more dominant, are more sensitive to drought than more xeric species, such as oaks (Quercus) and hickory (Carya), especially at moderate and extreme drought intensities. Although more extreme droughts produce a larger annual growth reduction, mild droughts resulted in the largest cumulative growth decreases due to their higher frequency. When using global climate model projections, all scenarios show drought frequency increasing substantially (3–9 times more likely) by 2100. Thus, the ongoing demographic shift toward more mesic species in the eastern United States combined with drier conditions results in larger drought‐induced growth declines, suggesting that drought will have an even larger impact on aboveground carbon uptake in the future in the eastern United States. [ABSTRACT FROM AUTHOR]

Background: HIV is associated with an increased risk of progression to chronic kidney disease (CKD), and this risk is higher in people of West African descent than many other ethnicities. Our study assessed the rates of eGFR change and predictors of rapid eGFR progression in patients receiving antiretroviral therapy (ART), including tenofovir disoproxil fumarate (TDF), in central Ghana between 2003 and 2018. Methods: This single-centre retrospective study enrolled people with HIV (PWH) initiating ART in Ghana between 2003–2018. Demographics, hepatitis B (HBsAg) status, ART regimens and estimated glomerular filtration rate (eGFR) measurements were recorded, and analyses including multi-level model linear regression were performed to determine predictors of greater levels of eGFR decline and risk of rapid eGFR decline. Results: Six hundred and fifty-nine adult participants were included in the study with a median follow-up time of 6 years (IQR 3.6–8.9). 149 participants (22.6%) also had confirmed HBV co-infection. eGFR mean values were lowest at the point of diagnosis and highest on the second measurement taken; mean eGFR slowly decreased over subsequent measures thereafter. TDF use was associated with the highest mean rate of eGFR decline of all nucleoside or nucleotide reverse transcriptase inhibitors (NRTIs) with a statistically significant greater annual decline of -1.08 mL/min/1.73m2/year (CI: -1.92, -0.24) compared with zidovudine. Nevirapine (-0.78mL /min/173m2/year; CI: -1.39, -0.17) and protease inhibitors (-1.55mL/mil/173m2/year; CI: -2.68, -0.41) were associated with greater eGFR declines compared with efavirenz. Negative HBsAg status was associated with greater eGFR decline compared with positive HBsAg status (-1.25mL/mil/173m2/year; CI 0.29. -2.20). Conclusions: Increased rates of eGFR decline amongst PWH in Ghana were associated with TDF, nevirapine, and protease inhibitor use as well as negative HBsAg status. Additional research using mortality outcome data is needed to closely assess long-term predictors of eGFR decline in African populations. [ABSTRACT FROM AUTHOR]

Host immune response is key for protection in tuberculosis, but the causative agent, Mycobacterium (M.) tuberculosis, manages to survive despite immune surveillance. Key mechanisms of immune protection have been identified, but the role of immunopathology in the peripheral blood of tuberculosis patients remains unclear. Tuberculosis immunopathology in the blood is characterised by patterns of immunosuppression and hyperinflammation. These seemingly contradictory findings and the pronounced heterogeneity made it difficult to interpret the results from previous studies and to derive implications of immunopathology. However, novel approaches based on comprehensive data analyses and revitalisation of an ancient plasma milieu in vitro assay connected inflammation with immunosuppressive factors in tuberculosis. Moreover, interrelations between the aberrant plasma milieu and immune cell pathology were observed. This review provides an overview of studies on changes in plasma milieu and discusses recent findings linking plasma factors to T‐cell and monocyte/macrophage pathology in pulmonary tuberculosis patients. [ABSTRACT FROM AUTHOR]

Background: The pulp and paper industry (P&PI) is undergoing significant disruption driven by global megatrends that necessitate advanced tools for predicting future behavior and adapting strategies accordingly. Methods: This work utilizes a multi-criteria framework to quantify the effects of digitalization, changes in social behavior, and sustainability as three major megatrends transforming the P&PI industry, with a specific focus on hygiene tissue products. Thus, the research combines a comprehensive literature review, insights from a Delphi study, and topic modeling to qualitatively and quantitatively assess the present and future impacts of these global megatrends. Results: The findings suggest an urgent need to identify alternative raw materials to prevent potential supply chain disruptions. Moreover, due to shifts in social behavior, it becomes critical for businesses to substantiate their sustainability claims with hard data to avoid the risk of a "greenwashing" perception among consumers. Conclusions: This study provides decision support for strategic planning by highlighting actionable insights, quantitative predictions, and trend analysis, alongside the examination of consumer and market trends. It aims to incorporate diverse stakeholder perspectives and criteria into decision-making processes, thereby enriching the strategic planning and sustainability efforts within the P&PI industry. [ABSTRACT FROM AUTHOR]

Background: Stigma related to skin neglected tropical diseases like Buruli ulcer (BU) and yaws has remained underexplored and existing studies are limited to individual diseases despite the WHO call for integration in disease management. Within two districts in central Ghana, we explored stigma associated with BU and yaws to understand overlaps and disease-specific nuances to help guide integrated interventions. Methodology/Principal findings: In-depth interviews were conducted with 31 current or formerly affected individuals to assess the experiences, effects and coping strategies adopted to manage disease related stigma. Data were analysed along broad themes based on the sociological construct of macro and micro interaction and Goffman's treatise on stigma. Disapproving community labels fueled by misconceptions were noted among BU participants which contributed to macro stigma experiences, including exclusion, discrimination and avoidance. In contrast, a high level of social acceptance was reported among yaws participants although some micro-level stigma (anticipated, felt and self-stigma) were noted by individuals with both diseases. While younger participants experienced name-calling and use of derogatory words to address affected body parts, older participants and caregivers discussed the pain of public staring. Stigma experiences had negative consequences on psychosocial well-being, schooling, and social relations, particularly for BU affected people. Problem-focused strategies including confrontation, selective disclosure and concealment as well as emotion-focused strategies (religious coping and self-isolation) were noted. Conclusions and significance: The types and levels of stigma varied for BU and yaws. Stigma experiences also differed for adults and children in this setting and these differences should be accounted for in integrated interventions for these skin NTDs. School health programs need to prioritize educating school teachers about skin NTDs and the negative impact of stigma on the wellbeing of children. Author summary: Stigma related to Neglected Tropical Diseases (NTDs) constitutes a burden on the social and economic life of affected people, their caregivers and communities. Current evidence on stigma has been limited to a small number of NTDs. The WHO recommends integration approaches to NTDs are therefore understanding stigma and its differential impact is important. We explored stigma experiences, effects and coping strategies simultaneously in BU and yaws in two districts in central Ghana. Findings showed nuances for macro-level stigma associated with BU; individuals were stigmatized by community members; interestingly, this was not noted for yaws. Negative effects of stigma found included psychosocial burden, effects on academic work and straining of social relationships. Some affected individuals dealt with the source of stigma actively avoiding disclosure, selective disclosure, concealment with clothing and confrontation. Emotion-focused strategies such as religious coping and self-isolation were reported; these were noted to aggravate psychosocial problems being experienced by affected people. We propose that, the differences in stigma among people affected by BU and yaws, and the role of age in determining types of stigma identified in this study should be considered in integrated interventions for skin NTDs. School health programs are encouraged to educate teachers about skin NTDs and the negative effects of stigma on students. [ABSTRACT FROM AUTHOR]

Fine root lifespan is a critical trait associated with contrasting root strategies of resource acquisition and protection. Yet, its position within the multidimensional "root economics space" synthesizing global root economics strategies is largely uncertain, and it is rarely represented in frameworks integrating plant trait variations. Here, we compiled the most comprehensive dataset of absorptive median root lifespan (MRL) data including 98 observations from 79 woody species using (mini-) rhizotrons across 40 sites and linked MRL to other plant traits to address questions of the regulators of MRL at large spatial scales. We demonstrate that MRL not only decreases with plant investment in root nitrogen (associated with more metabolically active tissues) but also increases with construction of larger diameter roots which is often associated with greater plant reliance on mycorrhizal symbionts. Although theories linking organ structure and function suggest that root traits should play a role in modulating MRL, we found no correlation between root traits associated with structural defense (root tissue density and specific root length) and MRL. Moreover, fine root and leaf lifespan were globally unrelated, except among evergreen species, suggesting contrasting evolutionary selection between leaves and roots facing contrasting environmental influences above vs. belowground. At large geographic scales, MRL was typically longer at sites with lower mean annual temperature and higher mean annual precipitation. Overall, this synthesis uncovered several key ecophysiological covariates and environmental drivers of MRL, highlighting broad avenues for accurate parametrization of global biogeochemical models and the understanding of ecosystem response to global climate change. [ABSTRACT FROM AUTHOR]

Although many medium-to-large terrestrial vertebrates are still counted by ground or aerial surveys, remote-sensing technologies and image analysis have developed rapidly in recent decades, offering improved accuracy and repeatability, lower costs, speed, expanded spatial coverage and increased potential for public involvement. This review provides an introduction for wildlife biologists and managers relatively new to the field on how to implement remote-sensing techniques (satellite and unoccupied aircraft systems) for counting large vertebrates on land, including marine predators that return to land to breed, haul out or roost, to encourage wider application of these technological solutions. We outline the entire process, including the selection of the most appropriate technology, indicative costs, procedures for image acquisition and processing, observer training and annotation, automation, and citizen science campaigns. The review considers both the potential and the challenges associated with different approaches to remote surveys of vertebrates and outlines promising avenues for future research and method development. [ABSTRACT FROM AUTHOR]

Viral encephalitis is a rare, yet severe neurological disorder. It poses a significant public health threat due to its high morbidity and mortality. Despite the disproportionate burden of the disease in impoverished African countries, the true extent of the problem remains elusive due to the scarcity of accurate diagnostic methods. The absence of timely and effective diagnostic tools, particularly Real-time Polymerase Chain Reaction, has led to misguided treatment, and an underestimation of the disease burden in Ghana. We conducted a prospective cross-sectional study to determine the viral aetiologies of encephalitis among patients presenting to a major referral hospital in Ghana from May 2019 and August 2022. The study aimed at providing a comprehensive information on the clinical epidemiology, and outcomes of viral encephalitis in Ghana. Clinical samples were collected from patients presenting with signs and symptoms of encephalitis and tested for viral agents using real-time polymerase chain reaction. We assessed the clinical epidemiology, risk factors and outcome of individuals using descriptive and logistic regression analysis. Seventy-seven (77) patients were enrolled unto the study. The participants frequently presented with fever (85.7%), seizures (80.5%), lethargy (64.9%) and headache (50.6%). Viruses were detected in 40.3% of the study participants in either cerebrospinal fluid, rectal or oral swab samples. The most frequently detected viruses were cytomegalovirus (48.4%), enteroviruses (38.7%) and HSV (29.0%). Twenty-one (27.3%) of the patients died while on hospital admission. Gender (OR = 5.70 (1.536–1.172), p = 0.01), and negative polymerase chain reaction test results were identified as significant factors associated with death. Antiviral treatment increased the chance of survival of viral encephalitis patients by 21.8%. Our results validate the crucial role of molecular tools as essential for the rapid diagnosis of viral encephalitis, enabling effective treatment and improved patient outcomes. This study contributes valuable epidemiological and clinical insight into viral encephalitis in Ghana. [ABSTRACT FROM AUTHOR]