In Situ Tracking of Water Oxidation Generated Nanoscale Dynamics in Layered Double Hydroxides Nanosheets.

Layered double hydroxides (LDHs) are potential catalysts for water oxidation, and it is recognized that they undergo dynamic evolution during the operation. However, little is known about the interfacial behaviors at the nanoscale under working conditions nor the underlying effects on electrocatalytic performance. Herein, using electrochemical atomic force microscopy, we in situ visualize the heterogeneous evolution of LDH nanosheets during oxygen evolution reaction (OER). By further combining density functional theory calculations, we elucidate the origin of the heterogeneous dynamics and their impact on the OER efficiency. Our findings demonstrate that NiCo LDHs transform to the catalytically active NiCoOx(OH)2-x phase during OER, and the redox transition between is accompanied by compressive and tensile strain, leading to in-plane contraction and reversible expansion of the nanosheets. Nonisotropic strain and out-of-plane strain relaxation due to defects and interparticle interactions result in cracking and wrinkling in the nanostructure, which is responsible for the partial activation and long-term deterioration of LDH electrocatalysts toward the OER. With this knowledge, we suggest and validate that engineering defects can precisely tune these dynamic behaviors, improving the OER activity and stability among LDH-based electrocatalysts.

Cardiovascular disease risk perceptions and influencing factors among Chinese systemic lupus erythematosus patients.

BACKGROUND: Systemic Lupus Erythematosus patients (SLE) are at a higher risk of cardiovascular events than the general population. This study aimed to investigate the risk perception of cardiovascular disease (CVD) and to analyze its influence factors among Chinese SLE patients. METHODS: This was a cross-sectional study. Convenience sampling was used to select 201 patients with SLE who had attended the outpatient and inpatient departments of the Department of Rheumatology and Immunology at the First Affiliated Hospital of the University of Science and Technology of China from November 2022 to March 2023. The following were used in the study: the Chinese version of the Attitudes and Beliefs about Cardiovascular Disease Risk Questionnaire, the Social Support Rating Scale, the Connor-Davidson Resilience Scale, the General Self-Efficacy Scale, the Hospital Anxiety and Depression Scale, the Health Literacy Management Scale, and sociodemographic and disease-related data. RESULTS: The mean (standard deviation) risk perception score of CVD patients with SLE was 57.18 ± 13.02. A Pearson correlation analysis showed that CVD risk perceptions were positively correlated with health literacy (r = 0.152, p < .05) and depression (r = 0.277, p < .05), and negatively correlated with social support (r = -0.393, p < .05) and psychological resilience (r = -0.374, p < .05). A multiple linear regression analysis showed that body mass index (BMI), family history, health literacy, depression, social support, and psychological resilience were the main factors influencing CVD risk perceptions among Chinese SLE patients (p < .05). CONCLUSIONS: Body mass index, family history, health literacy, depression, social support, and psychological resilience influenced CVD risk perceptions among Chinese SLE patients. Healthcare workers should objectively and accurately assess the levels of CVD risk perception among SLE patients, identify the risk factors of CVD, adopt effective health risk communication strategies to help patients develop appropriate risk perceptions, and raise risk awareness to adopt active coping approaches to reduce risk.

Comparative transcriptome profile analysis of granulosa cells from porcine ovarian follicles during early atresia.

At various stages of ovarian follicular development, more than 99% of follicles will be eliminated through a degenerative process called atresia. The regulatory mechanisms of atresia have been elucidated to some extent, involving hormones, growth factors, cytokines, and other factors. However, the stimuli initiating atresia in follicular granulosa cells remain unknown. In this study, we isolated the granulosa cells from porcine ovarian follicles (3-5 mm diameter) divided into healthy follicles (HFs) and early atretic follicles (EAFs). We applied high-throughput RNA sequencing to identify and compare differentially expressed genes (DEGs) between HFs and EAFs. A total of 31,694 genes were detected, of which 21,806 were co-expressed in six samples, and 243 genes (p < 0.05; FDR < 0.05) were differentially expressed (DEGs), including 123 downregulated and 120 upregulated in EAFs. GO analysis highlighted hormone metabolism, plasma membrane localization, and transporter activity. The pathway analysis indicated that 51 DEGs, involved in steroidogenesis, cell adhesion molecules, and TGF-beta signaling pathways, were highly related to atresia. Additionally, the interaction network of DEGs (p < 0.01; FDR < 0.05) using STRING highlighted LHR, ACACB, and CXCR4 as central nodes. In summary, this transcriptome analysis enriched our knowledge of the shifted mechanisms in granulosa cells during early atresia and provided novel perspectives into the atresia initiation.

Mowing aggravates the adverse effects of nitrogen addition on soil acid neutralizing capacity in a meadow steppe.

Soil acidification induced by reactive nitrogen (N) inputs is a major environmental issue in grasslands, as it lowers the acid neutralizing capacity (ANC). The specific impacts of different N compound forms on ANC remain unclear. Grassland management practices like mowing and grazing can remove a considerable amount of soil N and other nutrients, potentially mitigating soil acidification by removing N from the ecosystem or aggravating it by removing base cations. However, empirical evidence regarding the joint effects of adding different forms of N compounds and mowing on ANC changes in different-sized soil aggregates is still lacking. This study aimed to address this knowledge gap by examining the effects of three N compounds (urea, ammonium nitrate, and ammonium sulfate) combined with mowing (mown vs. unmown) on soil ANC in different soil aggregate sizes (>2000 µm, 250-2000 µm, and <250 µm) through a 6-year field experiment in Inner Mongolia grasslands. We found that the average decline in soil ANC caused by ammonium sulfate (AS) addition (-78.9%) was much greater than that by urea (-25.0%) and ammonium nitrate (AN) (-52.1%) as compared to control. This decline was attributed to increased proton (H+) release from nitrification and the leaching of exchangeable Ca2+ and Mg2+. Mowing aggravated the adverse effects of urea and AN on ANC, primarily due to the reduction in soil organic matter (SOM) contents and the removal of exchangeable Ca2+, K+, and Na + via plant biomass harvest. This pattern was consistent across all aggregate fractions. The lack of variation in soil ANC among different soil aggregate fractions is likely due to the contrasting trend in the distribution of exchangeable Ca2+ and Mg2+. Specifically, the concentration of exchangeable Ca2+ increased with increasing aggregate size, while the opposite was true for that of exchangeable Mg2+. These findings underscore the importance of considering the forms of N compounds when assessing the declines of ANC induced by N inputs, which also calls for an urgent need to reduce N emissions to ensure the sustainable development of the meadow ecosystems.

The Optimal Layer for Breast Augmentation in an Autologous Fat Grafting Murine Model.

BACKGROUND: Fat grafting is an effective procedure for breast augmentation, but the variations in this technique result in unpredictable fat retention. Therefore, animal models are needed to simulate the operation and the optimal layer for fat retention. OBJECTIVES: An autologous fat grafting murine model for breast augmentation was built to detect a new layer for fat grafting in the chest. METHODS: The left side of the female rat inguinal fat flap was harvested, dissected into small pieces, and autotransplanted into 3 different layers of the breast. Retention rate and hematoxylin and eosin (H&E) staining were measured at 1, 4, 8 12, and 16 weeks. Immunofluorescence staining was utilized to detect adipocytes and endothelial cells, and immunohistochemistry was conducted to evaluate the expression of integrins ß1 and α6. RESULTS: The volume of fat grafts slightly grew in the intramuscular and submuscular layers at Week 4. Retention rates in the subcutaneous layer and submuscular layer were significantly higher than the intramuscular layer at Week 16. H&E staining showed that oil cysts existed in the subcutaneous layer throughout the 16 weeks. At the terminal time point, well-vascularized mature adipose structures were observed in intramuscular and submuscular layers, with smaller adipocytes in intramuscular layers. Immunohistochemistry analysis showed that integrin ß1 was identically expressed in every adipocyte in all the layers, whereas integrin α6 selectively expressed in bigger adipocytes in the intramuscular layer. The expression intensities of integrin ß1 and α6 were significantly higher in the intramuscular layer than in the subcutaneous and submuscular layers. CONCLUSIONS: The angiogenic and moderate mechanical environment makes the submuscular layer the optimal layer for fat retention.

EPOR activation attenuates colitis via enhancing LC3B-dependent apoptotic cell clearance.

Systemic immune activation and excessive inflammatory response, induced by intestinal barrier damage, are the major characteristics of inflammatory bowel disease (IBD). Excessive apoptotic cell accumulation leads to the production of a large number of inflammatory factors, further aggravating IBD development. Gene set enrichment analysis data showed that the homodimeric erythropoietin receptor (EPOR) was highly expressed in the whole blood of patients with IBD. EPOR is specifically expressed in intestinal macrophages. However, the role of EPOR in IBD development is unclear. In this study, we found that EPOR activation significantly alleviated colitis in mice. Furthermore, in vitro, EPOR activation in bone marrow-derived macrophage (BMDMs) promoted microtubule-associated protein 1 light chain 3B (LC3B) activation and mediated the clearance of apoptotic cells. Moreover, our data showed that EPOR activation facilitated the expression of phagocytosis- and tissue-repair-related factors. Our findings suggest that EPOR activation in macrophages promotes apoptotic cell clearance, probably via LC3B-associated phagocytosis (LAP), providing a new mechanism for understanding pathological progression and a novel potential therapeutic target for colitis.

Enhancement of the therapeutic efficacy of mesenchymal stem cell-derived exosomes in osteoarthritis.

Osteoarthritis (OA), a common joint disorder with articular cartilage degradation as the main pathological change, is the major source of pain and disability worldwide. Despite current treatments, the overall treatment outcome is unsatisfactory. Thus, patients with severe OA often require joint replacement surgery. In recent years, mesenchymal stem cells (MSCs) have emerged as a promising therapeutic option for preclinical and clinical palliation of OA. MSC-derived exosomes (MSC-Exos) carrying bioactive molecules of the parental cells, including non-coding RNAs (ncRNAs) and proteins, have demonstrated a significant impact on the modulation of various physiological behaviors of cells in the joint cavity, making them promising candidates for cell-free therapy for OA. This review provides a comprehensive overview of the biosynthesis and composition of MSC-Exos and their mechanisms of action in OA. We also discussed the potential of MSC-Exos as a therapeutic tool for modulating intercellular communication in OA. Additionally, we explored bioengineering approaches to enhance MSC-Exos' therapeutic potential, which may help to overcome challenges and achieve clinically meaningful OA therapies.

A new abietane diterpenoid from Lycopodium complanatum.

A new abietane diterpenoid, 1ß, 11-epoxyabieta-12-hydroxy-8, 11, 13-triene-7-one (1), along with three known compounds (2-4), was isolated from Lycopodium complanatum. Their structures were confirmed by the analysis of 1D, 2D NMR and HRESIMS data, and comparison with previous spectral data. All compounds were tested for inhibitory activities against A549, HepG2 and MCF-7 tumor cell lines. [Figure: see text].

The Role of Circular RNAs in the Physiology and Pathology of the Mammalian Ovary.

Circular RNAs (circRNAs) are an abundant class of endogenous non-coding RNAs (ncRNAs) generated from exonic, intronic, or untranslated regions of protein-coding genes or intergenic regions. The diverse, stable, and specific expression patterns of circRNAs and their possible functions through cis/trans regulation and protein-coding mechanisms make circRNA a research hotspot in various biological and pathological processes. It also shows practical value as biomarkers, diagnostic indicators, and therapeutic targets. This review summarized the characteristics, classification, biogenesis and elimination, detection and confirmation, and functions of circRNAs. We focused on research advances circRNAs in the mammalian ovary under conditions including ovarian cancer, polycystic ovarian syndrome (PCOS), and maternal aging, as well as during reproductive status, including ovarian follicle development and atresia. The roles of circRNAs in high reproductive traits in domestic animals were also summarized. Finally, we outlined some obstructive factors and prospects to work with circRNA, aiming to provide insights into the functional research interests of circRNAs in the reproduction and gynecology areas.

Association between alcohol consumption in midlife and cognitive function in old age: Findings from the China health and Nutrition Survey.

BACKGROUND AND AIMS: Alcohol consumption has been reported to impair the physical and mental health of the elderly. This study aimed to explore the association between alcohol consumption patterns in midlife and cognition in the elderly among the Chinese population. METHODS AND RESULTS: Study subjects were individuals aged ≥45 years in the shared database of the China Health and Nutrition Survey in 1997, who were followed up in 2006. A questionnaire was used to collect information about alcohol consumption (frequency, amount and type). Alcohol consumption (grams/week) was classified into none, light (≤84), light-to-moderate (84.01-168), moderate-to-heavy (168.01-336) and heavy (≥336.01) categories in men, and none, light (<42) and moderate (≥42) categories in women. Cognitive function was measured in 2006 using a subset of items from the modified Telephone Interview for Cognitive Status. The lowest quintile was used as the cut-off point for cognitive impairment. A multivariate logistic regression model was applied. The study involved 1926 participants with a mean age of 56.91 years, and men accounted for 51.66% of the total participants. Drinking behaviours and cognitive scores had significant sexual difference (P < 0.001). Cognitive impairment was identified in 135 men and 237 women. Compared with light drinking, heavy drinking and non-drinking were associated with cognitive impairment in men [adjusted odds ratio (aOR) and 95% CI were 2.19 (1.59-3.00), 1.54 (1.21-1.96), respectively; P < 0.001]. Compared with light drinkers, female non-drinkers and moderate drinkers were associated with cognitive impairment [aOR and 95% CI were 1.54 (1.16-2.03) and 1.75 (1.08-2.85), respectively; P < 0.001]. CONCLUSIONS: Scientific evidence on the adverse effects of heavy drinking on elderly cognition and the possibly protective effects of light drinking could influence policy decisions on alcohol consumption in China.

Combined lifestyle factors and risk of incident type 2 diabetes and prognosis among individuals with type 2 diabetes: a systematic review and meta-analysis of prospective cohort studies.

AIMS/HYPOTHESIS: A healthy lifestyle has been widely recommended for the prevention and management of type 2 diabetes. However, no systematic review has summarised the relationship between combined lifestyle factors (including, but not limited to, smoking, alcohol drinking, physical activity, diet and being overweight or obese) and incident type 2 diabetes and risk of health outcomes among diabetic individuals. METHODS: EMBASE and PubMed were searched up to April 2019 without language restrictions. References included in articles in relevant publications were also screened. Cohort studies investigating the combined associations of at least three lifestyle factors with incident type 2 diabetes and health outcomes among diabetic individuals were included. Reviewers were paired and independently screened studies, extracted data and evaluated study quality. Random-effects models were used to calculate summary HRs. Heterogeneity and publication bias tests were also conducted. RESULTS: Compared with participants considered to have the least-healthy lifestyle, those with the healthiest lifestyle had a 75% lower risk of incident diabetes (HR 0.25 [95% CI 0.18, 0.35]; 14 studies with approximately 1 million participants). The associations were largely consistent and significant among individuals from different socioeconomic backgrounds and baseline characteristics. Among individuals with type 2 diabetes (10 studies with 34,385 participants), the HRs (95% CIs) were 0.44 (0.33, 0.60) for all-cause death, 0.51 (0.30, 0.86) for cardiovascular death, 0.69 (0.47, 1.00) for cancer death and 0.48 (0.37, 0.63) for incident cardiovascular disease when comparing the healthiest lifestyle with the least-healthy lifestyle. CONCLUSIONS/INTERPRETATION: Adoption of a healthy lifestyle is associated with substantial risk reduction in type 2 diabetes and long-term adverse outcomes among diabetic individuals. Tackling multiple risk factors, instead of concentrating on one certain lifestyle factor, should be the cornerstone for reducing the global burden of type 2 diabetes.

Combined lifestyle factors, incident cancer, and cancer mortality: a systematic review and meta-analysis of prospective cohort studies.

BACKGROUND: Cancer poses a huge disease burden, which could be reduced by adopting healthy lifestyles mainly composed of healthy diet, body weight, physical activity, limited alcohol consumption, and avoidance of smoking. However, no systematic review has summarised the relations of combined lifestyle factors with cancer morbidity and mortality. METHODS: EMBASE and PubMed were searched up to April 2019. Cohort studies investigating the association of combined lifestyle factors with risks of incident cancer and cancer mortality were selected. Summary hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated using random-effects models. Heterogeneity and publication bias tests were conducted. RESULTS: The HRs (95% CIs) comparing individuals with the healthiest versus the least healthy lifestyles were 0.71 (0.66-0.76; 16 studies with 1.9 million participants) for incident cancer and 0.48 (0.42-0.54; 30 studies with 1.8 million participants) for cancer mortality. Adopting the healthiest lifestyles was also associated with 17 to 58% lower risks of bladder, breast, colon, endometrial, oesophageal, kidney, liver, lung, rectal, and gastric cancer. The relations were largely consistent and significant among participants with different characteristics in the subgroup analyses. CONCLUSIONS: Adopting healthy lifestyles is associated with substantial risk reduction in cancer morbidity and mortality, and thus should be given priority for cancer prevention.

Effects of circadian rhythm disorder on the hippocampus of SHR and WKY rats.

The present study investigated the effects of circadian rhythm disorder (CRD) on the hippocampus of SHR and WKY rats. Male SHR rats (n = 27) and WKY rats (n = 27) were randomly divided into six groups: SHR and WKY normal (N)CR, SHR and WKY CRD 16/8 (CRD16/8), and SHR and WKY CRD 12/12 (CRD12/12). Activity patterns were adjusted using different photoperiods over 90 days and any changes were recorded. Rats were tested in the Morris water maze and in a novel object recognition experiment; serologic analysis, magnetic resonance imaging (diffusion tensor imaging + arterial spin labeling), hippocampal Nissl staining, Fluoro-Jade B staining, and immunohistochemistry were also performed. The results showed that both types of inverted photoperiod reduced CR amplitude and prolonged the circadian period. CRD and hypertension reduced memory performance and novel object recognition and preference. The decreases in memory and preference indices were greater in rats in the CRD12/12 group compared to the CRD16/8 group. CRD and hypertension decreased fractional anisotropy values, the number of neurons and astrocytes in the hippocampus, and the expression of brain-derived neurotrophic factor and synapsin 1; it also enhanced the degeneration of neurons and microglia and reduced blood flow in the hippocampus, and increased nuclear factor κB, caspase, neuron-specific enolase, and interleukin-6 levels. These findings reveal a biological basis for the link between CRD and cognitive decline, which has implications for CRD caused by shift work and other factors.

Effects of nitrogen and water addition on trace element stoichiometry in five grassland species.

A 9-year manipulative experiment with nitrogen (N) and water addition, simulating increasing N deposition and changing precipitation regime, was conducted to investigate the bioavailability of trace elements, iron (Fe), manganese (Mn), copper (Cu), and zinc (Zn) in soil, and their uptake by plants under the two environmental change factors in a semi-arid grassland of Inner Mongolia. We measured concentrations of trace elements in soil and in foliage of five common herbaceous species including 3 forbs and 2 grasses. In addition, bioaccumulation factors (BAF, the ratio of the chemical concentration in the organism and the chemical concentration in the growth substrate) and foliar Fe:Mn ratio in each plant was calculated. Our results showed that soil available Fe, Mn and Cu concentrations increased under N addition and were negatively correlated with both soil pH and cation exchange capacity. Water addition partly counteracted the positive effects of N addition on available trace element concentrations in the soil. Foliar Mn, Cu and Zn concentrations increased but Fe concentration decreased with N addition, resulting in foliar elemental imbalances among Fe and other selected trace elements. Water addition alleviated the effect of N addition. Forbs are more likely to suffer from Mn toxicity and Fe deficiency than grass species, indicating more sensitivity to changing elemental bioavailability in soil. Our results suggested that soil acidification due to N deposition may accelerate trace element cycling and lead to elemental imbalance in soil-plant systems of semi-arid grasslands and these impacts of N deposition on semi-arid grasslands were affected by water addition. These findings indicate an important role for soil trace elements in maintaining ecosystem functions associated with atmospheric N deposition and changing precipitation regimes in the future.

Photochemical Synthesis of Shape-Controlled Nanostructured Gold on Zinc Oxide Nanorods as Photocatalytically Renewable Sensors.

Biosensors always suffer from passivation that prevents their reutilization. To address this issue, photocatalytically renewable sensors composed of semiconductor photocatalysts and sensing materials have emerged recently. In this work, we developed a robust and versatile method to construct different kinds of renewable biosensors consisting of ZnO nanorods and nanostructured Au. Via a facile and efficient photochemical reduction, various nanostructured Au was obtained successfully on ZnO nanorods. As-prepared sensors concurrently possess excellent sensing capability and desirable photocatalytic cleaning performance. Experimental results demonstrate that dendritic Au/ZnO composite has the strongest surface-enhanced Raman scattering (SERS) enhancement, and dense Au nanoparticles (NPs)/ZnO composite has the highest electrochemical activity, which was successfully used for electrochemical detection of NO release from cells. Furthermore, both of the SERS and electrochemical sensors can be regenerated efficiently for renewable applications via photodegrading adsorbed probe molecules and biomolecules. Our strategy provides an efficient and versatile method to construct various kinds of highly sensitive renewable sensors and might expand the application of the photocatalytically renewable sensor in the biosensing area.

Responses of Soil Bacterial Communities to Nitrogen Deposition and Precipitation Increment Are Closely Linked with Aboveground Community Variation.

It has been predicted that precipitation and atmospheric nitrogen (N) deposition will increase in northern China; yet, ecosystem responses to the interactive effects of water and N remain largely unknown. In particular, responses of belowground microbial community to projected global change and their potential linkages to aboveground macro-organisms are rarely studied. In this study, we examined the responses of soil bacterial diversity and community composition to increased precipitation and multi-level N deposition in a temperate steppe in Inner Mongolia, China, and explored the diversity linkages between aboveground and belowground communities. It was observed that N addition caused the significant decrease in bacterial alpha-diversity and dramatic changes in community composition. In addition, we documented strong correlations of alpha- and beta-diversity between plant and bacterial communities in response to N addition. It was found that N enriched the so-called copiotrophic bacteria, but reduced the oligotrophic groups, primarily by increasing the soil inorganic N content and carbon availability and decreasing soil pH. We still highlighted that increased precipitation tended to alleviate the effects of N on bacterial diversity and dampen the plant-microbe connections induced by N. The counteractive effects of N addition and increased precipitation imply that even though the ecosystem diversity and function are predicted to be negatively affected by N deposition in the coming decades; the combination with increased precipitation may partially offset this detrimental effect.

Examining the Effects of Biochar Application on Soil Phosphorus Levels and Phosphatase Activities with Visible and Fluorescence Spectroscopy

Biochar could be got from crop straw which contain rich carbon under oxygen free or oxygen limited conditions at low temperature. The application of biochar into soil is beneficial to ease the pressure of handling straw, reduce pollution, reduce greenhouse gas emissions and improve soil quality. This study was carried out in a cornfield containing meadow brown soil at the lower reaches of Liao River which was treated with different amounts of biochar (0, 360, 1 800, 3 600 kg·ha-1) and fertilizer. We investigated the contents of soil available phosphorus (AP), organic P (OP) and total P (TP). We also investigated the enzyme activities of soil acid phosphatase (AcP), alkaline phosphatase (AlP) and phosphodiesterase (PD) via a fluorescence spectroscopy method by using a fluorescent conjugated polymer as the substrate. Soil AP contents increased drastically with the increasing application of biochar, whereas the OP and TP contents exhibited little change. The increase in AP contents was ascribed to the introduction of P into the soil via biochar. Soil AlP and PD activities increased with increasing biochar application. Soil AcP activity increased significantly after the application of the appropriate amount of biochar (1 800 kg·ha-1), whereas it was inhibited by the application of high levels of biochar (3 600 kg·ha-1), perhaps due to the intrinsic alkalinity of biochar. The effect of Biochar inputs on soil phosphorus element and phosphatase activity is the comprehensive embodiment of the soil physical properties, chemical properties, and microbial community structure and metabolic capacity. We should further study such item. The fluorescent microplate method used in this study has many advantages, such as accuracy, rapidness and simple to perform.

External Validation and Further Exploration of Fall Prediction Models Based on Questionnaires and Daily-Life Trunk Accelerometry.

Ambulatory measurements of trunk accelerations can provide valuable insight into the amount and quality of daily life activities. Such information has been used to create models to identify individuals at high risk of falls. However, external validation of such prediction models is lacking, yet crucial for clinical implementation. We externally validated 3 previously described fall prediction models. Complete questionnaires and 1-week trunk acceleration data were obtained from 263 community-dwelling people (mean age 71.8 years, 68.1% female). To validate models, we first used the coefficients and optimal cutoffs from the original cohort, then recalibrated the original models, as well as optimized parameters based on our new cohort. Among all participants, 39.9% experienced falls during a 6-month follow-up. All models showed poor precision (0.20-0.49), poor sensitivity (0.32-0.58), and good specificity (0.45-0.89). Calibration of the original models had limited effect on model performance. Using coefficients and cutoffs optimized on the external cohort also had limited benefits. Lastly, the odds ratios in our cohort were different from those in the original cohort, which indicated that gait characteristics, except for the index of harmonicity ML (medial-lateral direction), were not statistically associated with falls. Fall risk prediction in our cohort was not as effective as in the original cohort. Recalibration as well as optimized model parameters resulted in a limited increase in accuracy. Fall prediction models are highly specific to the cohort studied. This highlights the need for large representative cohorts, preferably with an external validation cohort.