Key Thresholds Research Articles

Settling down with anthropomorphic clay figurines in eastern North America

Indigenous peoples have occupied eastern North America for over 10,000 years; yet the earliest anthropomorphic figurines were only manufactured in the past several thousand years. This emergence of human figurine traditions in eastern North America is correlated with increased settlement permanence, and community size related to key demographic thresholds. In this study, I present an overview of two previously unreported figurine assemblages from the Middle Woodland period in Illinois and use these assemblages as a jumping-off point to examine the emergence of early human figurines in eastern North America. To illustrate the importance of the correlation between anthropomorphic figurines and settling down, I focus on what figurines do that encouraged the emergence of widespread traditions of figurine manufacture and use as the size of affiliative communities increased. This study involves examining early figurines and their broader context through the lens of a model of the socioeconomic dynamics of settling down in conjunction with an examination of the materiality of miniature 3-D anthropomorphic figurines. Key to this latter perspective is understanding not what figurines represent but what they do.

Identifying critical source areas of non-point source pollution to enhance water quality: Integrated SWAT modeling and multi-variable statistical analysis to reveal key variables and thresholds

By integrating soil and water assessment tool (SWAT) modeling and land use and land cover (LULC) based multi-variable statistical analysis, this study aimed to identify driving factors, potential thresholds, and critical source areas (CSAs) to enhance water quality in southern Alabama and northwest Florida's Choctawhatchee Watershed. The results revealed the significance of forest cover and of the lumped developed areas and cultivated crops ("Source Areas") in influencing water quality. The stepwise linear regression analysis based on self-organizing maps (SOMs) showed that a negative correlation between forest percent cover and total nitrogen (TN), organic nitrogen (ORGN), and organic phosphorus (ORGP), highlighting the importance of forests in reducing nutrient loads. Conversely, Source Area percentage was positively correlated with total phosphorus (TP) loads, indicating the influence of human activities on TP levels. The receiver operating characteristic (ROC) curve analysis determined thresholds for forest percentage and Source Area percentage as 37.47 % and 20.26 %, respectively. These thresholds serve as important reference points for identifying CSAs. The CSAs identified based on these thresholds covered a relatively small portion (28 %) but contributed 47 % of TN and 50 % of TP of the whole watershed. The study underscores the importance of considering both physical process-based modeling and multi-variable statistical analysis for a comprehensive understanding of watershed management, i.e., the identification of CSAs and the associated variables and their tipping points to maintain water quality.

Agricultural Production Efficiency and Ecological Transformation Efficiency in the Yangtze River Economic Belt

Measuring the agricultural production efficiency (APE) and the ecological transformation efficiency (ETE) is key to agricultural modernization and regional ecological civilization construction. Based on the agricultural input–output dataset of the Yangtze River Economic Belt (YREB) from 2000 to 2015, we use the panel stochastic frontier analysis (SFA) to measure the APE and ETE to explore the spatiotemporal patterns of regional APE and ETE from the geographical perspective. We rely on the quantitative association characteristics to explore the key threshold of ecological economic development in agriculture. The results show that: (1) In the study period, the APE increased from 0.2993 to 0.5495, indicating that the cumulative growth of the whole period was 83.60%, and the high-value units gradually changed from point distribution to spatial distribution; (2) Although the ETE of the YREB increased from 2000 to 2015, the proportion of the first-class species was still only 7.26% in 2015, and the inverted U-shaped polarization distribution characteristics of the high-efficiency cities and the band-like structure of global decision-making units were formed at the same time; (3) The improvement of ETE has obvious segment distribution and threshold crossing characteristics, and the APE is equal to 0.661, which is the threshold for high-speed growth and low-speed growth of ETE. The research framework, spatiotemporal rules and key thresholds have reference value for agricultural modernization and ecological civilization construction.

Insights into the relationship between hydraulic safety, hydraulic efficiency and tree structural complexity from terrestrial laser scanning and fractal analysis

Key messageThis research focused on the interplay between tree structural complexity and drought tolerance, unraveling the crucial role of Db as an indicator of hydraulic efficiency and vulnerability in several tree species.The potential of trees to adapt to drier and hotter climates will determine the future state of forests in the wake of a changing climate. Attributes connected to the hydraulic network are likely to determine a tree’s ability to endure drought. However, how a tree’s architectural attributes related to drought tolerance remains understudied. To fill this gap, we compared the structural complexity of 71 trees of 18 species obtained from terrestrial laser scanning (TLS) with key hydraulic thresholds. We used three measures of xylem safety, i.e., the water potential at 12%, 50%, and 88% loss of hydraulic conductance (P12, P50, P88) and specific hydraulic conductivity (Ks) to assess the trees’ drought tolerance. TLS data were used to generate 3D attributes of each tree and to construct quantitative structure models (QSMs) to characterize the branching patterns. Fractal analysis (box-dimension approach) was used to evaluate the overall structural complexity of the trees (Db) by integrating horizontal and vertical extent as well as internal branching patterns. Our findings revealed a significant relationship between the structural complexity (Db) and the three measures of xylem safety along with Ks. Tree species with low structural complexity developed embolism-resistant xylem at the cost of hydraulic efficiency. Our findings also revealed that the Db had a stronger and more significant relationship with branch hydraulic safety and efficiency compared to other structural attributes examined. We conclude that Db seems to be a robust descriptor of tree architecture that relates to important branch hydraulic properties of a tree.

Electro-metabolic signaling.

Precise matching of energy substrate delivery to local metabolic needs is essential for the health and function of all tissues. Here, we outline a mechanistic framework for understanding this critical process, which we refer to as electro-metabolic signaling (EMS). All tissues exhibit changes in metabolism over varying spatiotemporal scales and have widely varying energetic needs and reserves. We propose that across tissues, common signatures of elevated metabolism or increases in energy substrate usage that exceed key local thresholds rapidly engage mechanisms that generate hyperpolarizing electrical signals in capillaries that then relax contractile elements throughout the vasculature to quickly adjust blood flow to meet changing needs. The attendant increase in energy substrate delivery serves to meet local metabolic requirements and thus avoids a mismatch in supply and demand and prevents metabolic stress. We discuss in detail key examples of EMS that our laboratories have discovered in the brain and the heart, and we outline potential further EMS mechanisms operating in tissues such as skeletal muscle, pancreas, and kidney. We suggest that the energy imbalance evoked by EMS uncoupling may be central to cellular dysfunction from which the hallmarks of aging and metabolic diseases emerge and may lead to generalized organ failure states-such as diverse flavors of heart failure and dementia. Understanding and manipulating EMS may be key to preventing or reversing these dysfunctions.

Conceptual framework for analyzing the sustainability of socio‐ecological systems with a focus on ecosystem services that support water security

AbstractWater security is a global concern sharpened by the biggest humanity challenge of climatic crisis. With the end of designing and implementing efficient and sustainable water management strategies, it is necessary to recognize the interdependence and coevolution between natural and social systems and understand how the double way relationships between these systems shape sustainability. The socio‐ecological systems (SES) sustainability approach is an alternative to this end. Conceptual challenges have been identified in the analysis of the sustainability of SES. These challenges include (i) A lack of clarity in the definition of SES sustainability, (ii) the non‐inclusion of some inherent SES characteristics that determine critical thresholds, and (iii) a lack of conceptual frameworks for analyzing the sustainability of SES and water security‐related ecosystem services. This study proposes a conceptual framework, based on a strong sustainability approach, for analyzing SES sustainability focusing on water security and addressing the above‐mentioned challenges. This conceptual development includes three elements: (i) the key thresholds to ensure ecological functionality; (ii) the benefits that society derives from ecological functioning and; (iii) the two‐way relationship between natural capital and social systems. Analyzing these three elements helps identification of different sustainability states of SESs, focusing on water security, in the presence of endogenous or exogenous drivers of change. The conceptualization and operationalization of SES sustainability focusing on water security allows the analysis of the trajectories of change and provides insights into the required water management strategies in the target territory.

Analysis of cell populations in the normal rhesus macaque (Macaca mulatta) lower intestinal tract and diagnostic thresholds for chronic enterocolitis.

Rhesus macaques (Macaca mulatta) are used extensively in biomedical research, often with a focus on the gastrointestinal tract, and yet a full characterization of their normal resident intestinal cell populations has not been published. In addition, chronic enterocolitis (CE), also known as idiopathic chronic diarrhea, affects up to 25% of colony-housed rhesus macaques, often requiring euthanasia for welfare concerns and severely limiting their value as a breeding animal or research subject. We aimed to characterize subjective and objective variables in sections of the ileum, cecum, colon, and rectum in 16 healthy rhesus macaques and compare these results with a cohort of 37 animals euthanized for CE to produce relevant diagnostic thresholds and to improve case definitions for future studies. We found neutrophils to be an infrequent but expected component of the large intestinal leukocyte population. Animals with CE had significantly increased total leukocyte populations between crypts in the cecum, colon, and rectum; variable increases in specific cell populations across all levels of the distal intestinal tract; and significantly increased intraepithelial CD3+ T cells in the colon and rectum. Concentrations of enteroendocrine cells, enterochromaffin cells, and intestinal mast cells were not significantly different between healthy and affected individuals. This study characterizes individual leukocyte populations in the rhesus macaque lower intestinal tract, is the first to evaluate rhesus macaque intestinal mast cells, and provides key diagnostic thresholds for evaluating animals with potential CE.

Driving factors for decoupling water resources ecological footprint and economic growth in water-deficient cities dominated by agriculture.

To explore the key factors and specific thresholds of water resources limiting economic development, and to provide technical support for water resources management in cities dominated by agriculture similar to Zhangjiakou. We used the Tapio elastic decoupling method to quantitatively evaluate the decoupling relationship between the water resources ecological footprint (WEF) and economic growth. Then the logarithmic mean Divisia index (LMDI) and mathematical statistics are used to identify the key factors and threshold effects. The results show a significant decreasing trend in the WEF and obvious spatial differences in Zhangjiakou between 2006 and 2015, with agricultural ecological footprint dominating all districts and counties (77.54 ± 14.35%). The changes in technological effect are a contributing factor to the decoupling between the WEF and the economy in Zhangjiakou, while the economic effect is the main restricting factor. In particular, there is a high correlation between the WEF and the number of water-saving irrigation machines and the total power of agricultural machinery. According to the findings, for water-scarce cities such as Zhangjiakou, where agriculture is the primary focus, it is suggested that increasing the number of agricultural machinery can effectively alleviate the problem of water scarcity constraining economic development.

Sample Size and Saturation: A Three-phase Method for Ethnographic Research with Multiple Qualitative Data Sources

Despite recent methodological advances in saturation, guidelines for its estimation in more complex research designs—such as ethnographic studies—have been lacking. We present an accessible, step-by-step approach to empirical assessment of data saturation, tested on a moderately sized ethnographic study with 109 combined direct observations and interviews. The three-phase method includes a priori sample size prediction, provisional saturation estimation during data collection, and post hoc confirmation. Post hoc analysis indicated we reached key thresholds of data saturation before ending fieldwork. We achieved 80% saturation at our 69th data collection event (63% of the full sample) and 90% saturation at our 91st data collection event (83% of the full sample). The method is designed to account for on-the-ground realities confronted in contemporary ethnographic research, including time constraints during fieldwork, and can accommodate studies with medium to large scopes, broad foci, heterogeneous populations, and analysis of multiple qualitative data sources.

The impact of sedative and vasopressor agents on cerebrovascular reactivity in severe traumatic brain injury

BackgroundThe aim of this study is to evaluate the impact of commonly administered sedatives (Propofol, Alfentanil, Fentanyl, and Midazolam) and vasopressor (Dobutamine, Ephedrine, Noradrenaline and Vasopressin) agents on cerebrovascular reactivity in moderate/severe TBI patients. Cerebrovascular reactivity, as a surrogate for cerebral autoregulation was assessed using the long pressure reactivity index (LPRx). We evaluated the data in two phases, first we assessed the minute-by-minute data relationships between different dosing amounts of continuous infusion agents and physiological variables using boxplots, multiple linear regression and ANOVA. Next, we assessed the relationship between continuous/bolus infusion agents and physiological variables, assessing pre-/post- dose of medication change in physiology using a Wilcoxon signed-ranked test. Finally, we evaluated sub-groups of data for each individual dose change per medication, focusing on key physiological thresholds and demographics.ResultsOf the 475 patients with an average stay of 10 days resulting in over 3000 days of recorded information 367 (77.3%) were male with a median Glasgow coma score of 7 (4–9). The results of this retrospective observational study confirmed that the infusion of most administered agents do not impact cerebrovascular reactivity, which is confirmed by the multiple linear regression components having p value > 0.05. Incremental dose changes or bolus doses in these medications in general do not lead to significant changes in cerebrovascular reactivity (confirm by Wilcoxon signed-ranked p value > 0.05 for nearly all assessed relationships). Within the sub-group analysis that separated the data based on LPRx pre-dose, a significance between pre-/post-drug change in LPRx was seen, however this may be more of a result from patient state than drug impact.ConclusionsOverall, this study indicates that commonly administered agents with incremental dosing changes have no clinically significant influence on cerebrovascular reactivity in TBI (nor do they impair cerebrovascular reactivity). Though further investigation in a larger and more diverse TBI patient population is required.

Effects of comprehensive landscape patterns on water quality and identification of key metrics thresholds causing its abrupt changes

Comprehensive landscape patterns influence water quality with multiple factors, complex processes, and scale dependence. However, studies identifying landscape thresholds causing abrupt water quality changes and characterizing the contribution of topography to water quality are still limited. Exploring the impact mechanisms of natural geographical and landscape characteristics on spatial and seasonal water quality variations is conducive to watershed water resource protection and ecosystem restoration. Based on water quality monitoring data of Minjiahe River in the typical headwater area of the upstream Dan River in China from 2019 to 2021, we employed redundancy analysis, partial redundancy analysis, and nonparametric change-point analysis to analyze the relationship between stream water quality and multi-spatial scale comprehensive landscape patterns, to obtain the interactive and independent contributions of different landscape categories at multi-spatial scales on water quality, and to find the key landscape threshold leading to abrupt changes in water quality. Results showed that landscape configuration, landscape composition, and topographic factors collectively explain over 89.1% of water quality variation. Most seasonal variations in water quality were primarily caused by landscape configuration. The landscape composition was mainly responsible for the differences in water quality variations among spatial scales. The topographic factors made the least independent contribution and had a potential impact on overall water quality variation. In order to protect the water quality of streams, it is more reasonable to regulate the landscape at different scales. At the sub-catchment scale, interspersion and juxtaposition index (IJI) and landscape shape index (LSI) should be controlled below 82% and 22. At the 100 m riparian scale, farmland, urban land, IJI, and LSI should be controlled below 29%, 6.5%, 92%, and 26, respectively. Our results provide important guidance for optimizing landscape patterns and water conservation in the watershed.

Predicting Chemotherapy Benefit across Different Races in Early-Stage Breast Cancer Patients Using the Oncotype DX Score.

Oncotype DX assay, a multigene molecular test, has been widely used to stratify relapse risk and guide chemotherapy treatment in breast cancer. However, the optimal threshold of the Oncotype DX score in predicting chemotherapy benefit and its racial variation has not been investigated. In this study, we apply a random forest survival model to the SEER-Oncotype cohort data (Surveillance, Epidemiology, and End Results with Oncotype DX test information for breast cancer patients) and determine chemotherapy benefit thresholds in early-stage, estrogen-receptor-positive (ER+), and HER2-negative (HER2-) patients of different races. Our results indicate that early-stage ER+, HER2-, and LN-/LN+ patients may benefit from receiving chemotherapy at a lower Oncotype DX score than current guidelines (Recurrence Score, RS > 25 or RS > 30) suggest. According to the estimated chemotherapy sensitivity thresholds from our models, 2.05-2.72-fold more lymph-node-negative (LN-) and 2.08-5.02-fold more lymph-node-positive (LN+) patients who may not currently be recommended for chemotherapy by their Oncotype DX test result may actually have the potential to benefit from chemotherapy. Furthermore, our models indicate a racial difference in chemotherapy benefit: white, black, and Asian women with early-stage ER+/LN- tumors benefit from chemotherapy when their Oncotype DX scores are greater than 19.9, 37.2, and 18.0, respectively. Our study provides a method for calibrating multigene molecular tests to help guide treatment decisions in racially and ethnically diverse patients with cancer. Specifically, we identify key chemotherapy sensitivity thresholds for the Oncotype DX recurrence score test in breast cancer patients and provide evidence that certain patients may benefit from receiving chemotherapy at a lower threshold than the current clinical guidelines suggest.

0463 Deep Learning Classification of Future PAP Adherence based on CMS and other Adherence Criteria

Abstract Introduction Improving positive airway pressure (PAP) adherence is crucial to sleep apnea therapy success. Although behavioral interventions may be deployed to increase PAP adherence, operationalization remains an ongoing clinical challenge. Treatment outcomes may be optimized by forecasting PAP use to identify patients at risk for non-adherence enabling early intervention. We build upon our previous work by leveraging a larger dataset, additional metadata, and new Deep Learning approaches to forecast future PAP adherence. Methods We collected a cohort of N=21,397 subjects with daily PAP usage recorded during 2015-2021. We defined the input to models as the number of minutes the PAP machine was used during each day for the first 30-days. The ground truth was defined as the PAP adherence of the patients at the 3-month, 6- month, and 1-year endpoints. Adherence was calculated based on a 30-day window as ≥4-hours of usage for ≥70% of nights. We evaluated a Deep Neural Network (DNN) model with 10-fold cross- validation to forecast future adherence by leveraging previous daily usage information. Results were compared to a naive method which assumes adherence at each time point equals adherence during the first 30-days. Results The DNN models predicted adherence with a sensitivity of 90%, 81%, 77% and a specificity of 90%, 81%, 77%, for 3-month, 6-month, and 1-year endpoints, with ROC-AUC values of 0.97, 0.89, and 0.84 respectively. The models converged to ROC-AUC performance >0.90 for the first 90-days within the first 7 to 14-days of PAP use. Conclusion DNN models demonstrated strong predictive performance for PAP adherence, as defined by the CMS adherence criteria, measured by sensitivity, specificity, and overall ROC-AUC results at clinically relevant 90-day, 6-month, and 1-year timepoints. AI approaches show promise as early predictors of the likelihood to meet key therapy utilization thresholds within the first 1-2 weeks of therapy, enabling early PAP intervention or transition to alternative therapies. Support (if any) AASM Foundation SRA205-SR-19

The responses of ecosystem water use efficiency to CO2, nitrogen deposition, and climatic drivers across China

The responses of ecosystem water use efficiency (WUE) to environmental perturbations are non-linearly dependent on how strongly coupled are water and carbon cycling. Here, we evaluate the structure of these non-linearities using two high-fidelity explainable machine learning (XML) models to disentangle the confounding effects of the air temperature (Ta), precipitation (PR), downward shortwave radiation (SR), atmospheric CO2 concentration (Ca), and nitrogen deposition (Ndep) on WUE. The findings suggest that mean annual PR plays a dominant role in shaping the spatial pattern of WUE. Spatially, WUE responded positively to PR and Ca but negatively to Ta and SR, while Ndep had little impact on WUE. For temporal trends, the spatial pattern of the mean annual WUE determined the spatial pattern of the WUE trend. Furthermore, the spatial patterns of the Ndep and Ca trends also contributed substantially to the spatial pattern of the WUE trend. Notably, the WUE and Ca trends exhibited negative correlations, while the WUE and Ndep trends showed positive or negative correlations depending on the different nutrient constraints on vegetation. The WUE growth rate responded negatively to SR in both spatial patterns and temporal trends. Additionally, using the trend of 0.077 K yr−1 and 0 mm yr−1 as the threshold, the trends of Ta and PR shifted from positive to negative relationships on WUE growth. Our results help identify key sensitivities and thresholds in WUE to environmental controls over space and time.

What We Know and Don’t Know About Climate Tipping Elements

As climate change continues, parts of the Earth system such as ice sheets, frozen soils, or the Amazon rainforest could shift—some quickly, some slowly—after crossing key thresholds or tipping points.

Large leaf hydraulic safety margins limit the risk of drought‐induced leaf hydraulic dysfunction in Neotropical rainforest canopy tree species

Abstract The sequence of key water potential thresholds from the onset of water stress to mortality, and the timing of stomatal closure with regard to leaf xylem embolism formation are essential to characterizing plant adaptive strategies to drought. This constitutes a critical knowledge gap for tropical rainforest species, which may be less vulnerable to drought than previously thought. We recorded key leaf and stem water potential thresholds, leaf hydraulic safety margins (HSMleaf), leaf stomatal safety margins (SSMleaf) and estimated native embolism levels during a normal‐intensity dry season across 18 neotropical rainforest tree species. We also solved a sequence of key water potential thresholds. Additionally, we provide a cross‐biome analysis of SSMleaf encompassing 97 species from four major biomes based on a literature survey. In the studied rainforest species, leaf turgor loss point, used as a surrogate for stomatal closure, typically occurred before the onset of leaf xylem embolism. Most species exhibited positive HSMleaf and SSMleaf, with contrasting values across species and nearly absent embolism levels during the dry season irrespective of the experienced midday leaf water potentials. Our results point out that leaf xylem embolism is not routine for Neotropical rainforest tree species. Based on our proposal of the water potential sequence for tropical rainforest trees, we argue that leaf xylem embolism is a rare event for these species. This was supported by the literature survey, indicating that across biomes, most woody species have rather large SSMleaf and that leaves of tropical rainforest trees are not necessarily more vulnerable than in other biomes. However, we found evidence that some tropical rainforest species may be more vulnerable than others to ongoing climate change. Our data provide an opportunity to parametrize tree‐based or land‐surface models for tropical rainforests. Read the free Plain Language Summary for this article on the Journal blog.

Abstract 855: Model-informed drug design (MIDD) exploration of a theoretical CD47xTAA bispecific antibody using available data from magrolimab, an anti-CD47 monoclonal antibody

Abstract Purpose: The goal of this study is to outline the process and utility of using fit-for-purpose, semi-mechanistic PK/PD modeling to inform the design of a theoretical CD47 bispecific antibody targeted to a generic tumor-associated antigen (CD47xTAA bsAb) with improved efficacy, tolerability, and PK compared to single target anti-CD47 therapies. Approach: To help guide the CD47xTAA bsAb design, a 3-compartment human model was built to include a target-mediated drug disposition (TMDD) component from CD47 expressed on red blood cells (RBC), white blood cells (WBC), and cells in the peripheral compartment. The model was parameterized using available literature data and calibrated against magrolimab human PK data that exhibited potential TMDD. The magrolimab model was used to identify key CD47 receptor occupancy (RO) thresholds associated with tolerability (the priming dose threshold) and efficacy (the recommended Phase 2 dose/RP2D threshold). Next, assumed drug properties and TAA expression levels for a CD47xTAA bsAb were implemented in a similar human model and drug PK and doses required to match key CD47 RO thresholds were explored across a range of single-arm binding affinities. Results: The calibrated magrolimab model projected target engagement levels on RBCs and WBCs and showed rapid antibody-induced CD47 pruning on RBCs that is consistent with clinical PD measurements. At TAA binding affinities that produce sufficient binding to tumor antigen, the model predicts that lowering the CD47 binding affinity allows for a higher starting dose that matches the priming threshold, while lowering the dose required to match the RP2D threshold. The model also shows that lowering the binding affinity to CD47 may improve PK exposure in the tumor compartment by reducing systemic CD47 TMDD. Conclusions: This modeling exercise demonstrates how semi-mechanistic PK/PD models can be used in model-informed drug design (MIDD) by leveraging the targeting advantage of avid bispecific antibody therapies and by using publicly available preclinical and clinical data. Furthermore, these model projections can help inform future studies with bispecific CD47 drug candidates. Citation Format: Emily A. Pace, Bjorn L. Millard. Model-informed drug design (MIDD) exploration of a theoretical CD47xTAA bispecific antibody using available data from magrolimab, an anti-CD47 monoclonal antibody [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 855.

A novel neighbor selection scheme based on dynamic evaluation towards recommender systems.

Collaborative filtering is a kind of widely used and efficient technique in various online environments, which generates recommendations based on the rating information of his/her similar-preference neighbors. However, existing collaborative filtering methods have some inadequacies in revealing the dynamic user preference change and evaluating the recommendation effectiveness. The sparsity of input data may further exacerbate this issue. Thus, this paper proposes a novel neighbor selection scheme constructed in the context of information attenuation to bridge these gaps. Firstly, the concept of the preference decay period is given to describe the pattern of user preference evolution and recommendation invalidation, and thus two types of dynamic decay factors are correspondingly defined to gradually weaken the impact of old data. Then, three dynamic evaluation modules are built to evaluate the user's trustworthiness and recommendation ability. Finally, A hybrid selection strategy combines these modules to construct two neighbor selection layers and adjust the neighbor key thresholds. Through this strategy, our scheme can more effectively select capable and trustworthy neighbors to provide recommendations. The experiments on three real datasets with different data sizes and data sparsity show that the proposed scheme provides excellent recommendation performance and is more suitable for real applications, compared to the state-of-the-art methods.

Inequalities in Immunization against Maternal and Neonatal Tetanus: A Cross-Sectional Analysis of Protection at Birth Coverage Using Household Health Survey Data from 76 Countries.

Substantial progress in maternal and neonatal tetanus elimination has been made in the past 40 years, with dramatic reductions in neonatal tetanus incidence and mortality. However, twelve countries have still not achieved maternal and neonatal tetanus elimination, and many countries that have achieved elimination do not meet key sustainability thresholds to ensure long-lasting elimination. As maternal and neonatal tetanus is a vaccine-preventable disease (with coverage of the infant conferred by maternal immunization during and prior to pregnancy), maternal tetanus immunization coverage is a key metric for monitoring progress towards, equity in, and sustainability of tetanus elimination. In this study, we examine inequalities in tetanus protection at birth, a measure of maternal immunization coverage, across 76 countries and four dimensions of inequality via disaggregated data and summary measures of inequality. We find that substantial inequalities in coverage exist for wealth (with lower coverage among poorer wealth quintiles), maternal age (with lower coverage among younger mothers), maternal education (with lower coverage among less educated mothers), and place of residence (with lower coverage in rural areas). Inequalities existed for all dimensions across low- and lower-middle-income countries, and across maternal education and place of residence across upper-middle-income countries. Though global coverage changed little over the time period 2001-2020, this obscured substantial heterogeneity across countries. Notably, several countries had substantial increases in coverage accompanied by decreases in inequality, highlighting the need for equity considerations in maternal and neonatal tetanus elimination and sustainability efforts.

Key Parameters and Thresholds Values for Obtaining High Performance Perovskite Solar Cells Indoors from Full Br Compositional and Bandgap Engineering

Perovskite solar cells (PSCs) have different theoretical optimal bandgaps (Eg) for outdoor and indoor light harvesting due to the different spectral distributions of the sun and indoor lamps. This work focuses on understanding how both indoor and outdoor photovoltaic (PV) performance of Cs0.05(MA0.17FA0.83)0.95Pb(I1–xBrx)3 PSCs depend on Br– content (x) spanning the whole 0–100% range, not only efficiency but also stability. Eg increases linearly with x: Eg/eV = 0.75x+1.48. Cells with x = 0.17 delivered the highest efficiency under indoor illumination, which did not correspond to the optimal theoretical bandgap. Via in depth analysis of crystal structure, morphology, and optoelectronic properties, we propose five key parameters and associated threshold values to be surpassed that enable one to achieve indoor efficiencies greater than 25% (1000 lx). First, films should possess average grain sizes greater than 300 nm (i.e., grain sizes > 70% of film thickness) and intergrain spacing ≪ 10 nm. Additionally, On/Off dark current and shunt/series resistance ratios should be higher than 102. Lastly the ratio between current density under indoor illumination and recombination currents in the dark should be >10. The aging rate of cells measured indoors (a fall of 65%) was higher than under 1 sun (41% fall), indicating that device performance is more sensitive to defects arising upon aging when measured under low intensity indoor light. Our investigation provides key parameters that can become a useful tool for researchers aiming to develop improved PSCs for indoor applications.