Excess Bias Research Articles

Ge-on-Si single-photon avalanche diode using a double mesa structure

We present experimental results of Ge-on-Si single-photon avalanche diodes based on a novel, to our knowledge, double mesa structure. Using this structure, the electric field at the mesa edges is suppressed compared to a traditional single mesa, leading to significant performance improvements. The dark current in linear mode shows a smaller increase for larger reverse voltages, resulting in a reduction by more than 260 times at low temperatures. Operated in the Geiger-mode at 110 K, the dark count rate in the double mesa is 100 times smaller. The devices achieve a dark count rate of 953 kHz, a single-photon detection efficiency of 7.3%, and a record-low jitter of 81 ps at an excess bias of 17.6% and a temperature of 110 K.

Non-genetic risk factors for preeclampsia: an updated umbrella review

Abstract Background Preeclampsia (PE) is a common pregnancy disorder with complex mechanisms, and multiple risk factors may contribute to its development. Our objective is to update our literature search from our previous umbrella review, summarizing recent evidence on non-genetic risk factors associated with PE and assessing their credibility to identify those supported by robust epidemiological evidence. Methods We searched PubMed, EMBASE, Scopus, and ISI Web of Science up to June 2023. For each meta-analysis, we computed summary effect estimates, 95% confidence intervals, 95% prediction intervals, and assessed heterogeneity using I², while also examining small-study effects and excess significance bias. Quality assessment was conducted using the AMSTAR-2 tool. Results 89 meta-analyses were identified, providing data on 219 associations. Of these, 151 (69%) showed statistically significant findings at P < 0.05, with 52 (24%) remaining significant at P < 10-6. Large or very large heterogeneity was observed in 121 (55%) associations. Evidence for small-study effects and excess significance bias was found in 27 (12%) and 29 (13%) associations, respectively. Only 16 (7%) presented convincing evidence: Polycystic Ovary Syndrome (PCOS), PCOS (adjusted), Obstructive Sleep Apnea (OSA), Obesity (adjusted), Chronic Kidney Disease (CKD), Pregnancy Intrahepatic Cholestasis, SARS-CoV-2 infection (adjusted), Oocyte donation (OD) vs. In vitro fertilization (IVF), Fresh embryo transfer vs. spontaneous conception (SC) (singleton), Frozen embryo transfer vs. SC, OD vs. SC (singleton), IVF-OD vs. IVF-AO, IVF-OD fresh ET vs. IVF-AO fresh ET, NC frozen embryo transfer vs. AC frozen embryo transfer, Fetal sex (term), and Smoking. Conclusions Maternal health conditions like PCOS, along with reproductive interventions such as OD and IVF, as well as lifestyle factors like obesity and smoking, showed convincing associations with PE. Key messages • Maternal health conditions, reproductive interventions, and lifestyle factors showed compelling evidence of association with preeclampsia. • Our findings emphasize the multifactorial nature of preeclampsia and suggest potential avenues for further research and clinical intervention.

Maternal factors for neural tube defects in offspring: An umbrella review.

We conducted an umbrella review focusing on maternal risk factors during pregnancy associated with neural tube defects (NTDs). Our search was in databases PubMed, Scopus, and Web of Science. We specifically targeted meta-analyses examining maternal factors during pregnancy in relation to NTDs. The comparison involved assessing metrics such as odds ratio (OR) or related risk ratios reported in the included studies, as well as parameters like heterogeneity (I²), 95% prediction interval, small-study effects, excess significance biases, and sensitivity analysis. Three risk factors for fetal NTDs, namely hyperthermia with an OR of 1.92, obesity with an OR of 1.68, and passive smoking with an OR of 1.90, were classified as highly suggestive evidence (Class II). Influenza, with an OR of 3.33, was considered a risk factor with suggestive evidence (Class III). Multivitamin supplementation during pregnancy, with an OR of 0.76, and low maternal vitamin B12, with an OR of 2.41, were categorized as weak evidence (Class IV). We identified four risk factors including hyperthermia, influenza, obesity, and passive smoking as suggestive or highly suggestive evidence for NTDs. Low maternal vitamin B12 was identified as a risk factor for NTDs, supported by weak evidence.

An Umbrella Review for Assessment of Treatment Effectiveness of Clear Aligners Compared to Conventional Fixed Appliances in Orthodontic Patients

Introduction Orthodontic improvements, mainly through the previous decade, have led to a substantial rise in patients’ esthetic needs. Traditional orthodontic procedures have been linked with a compromise in facial appearance, which increases concern among patients pursuing orthodontic treatment. Methods PubMed, MEDLINE, Google Scholar, and Cochrane Library of Systematic Reviews databases were searched using appropriate entry terms and Boolean operators. Search strategy was conducted till June 2022 for systematic reviews and meta-analyses. Publications were systematically assessed for eligibility, and two observers independently graded the methodologic quality using AMSTAR-2 tool. For each meta-analysis, we estimated the summary effect size by the use of random-effects and fixed-effects models and the 95% confidence interval. We estimated the between-study heterogeneity expressed by I 2 (defined as large for I 2 ≥50%), evidence of small-study effects (i.e., large studies had significantly more conservative results than smaller studies), and evidence of excess significance bias (i.e., more studies than expected with significant results). Results Overall, 16 unique systematic reviews and meta-analyses following the eligibility criteria were selected for umbrella review. The results of qualitative analysis of studies revealed that 4 studies had a critically low risk of bias, 11 showed low risk, and 1 study had moderate risk. The results of the meta-analysis favored clear aligners with respect to oral hygiene and root resorption parameters. When tooth movements were considered, the results favored conventional orthodontic treatment. Conclusion Clear aligner therapy (CAT) has significant advantages with regard to efficiency (treatment time, chair time) in mild-moderate malocclusion cases. The overall accuracy of CAT when compared to fixed orthodontic treatment was found to be 55-82%.

Role of diet in the risks of esophageal adenocarcinoma and squamous cell carcinoma: an updated umbrella review.

This updated umbrella review aimed to evaluate the evidence regarding the associations between dietary factors and the risks of esophageal squamous cell carcinoma (ESCC) and esophageal adenocarcinoma (EAC). The PubMed, Embase, Cochrane Library, and Web of Science databases were searched to identify relevant studies. The quality of the included meta-analyses was evaluated using A MeaSurement Tool to Assess systematic Reviews 2 (AMSTAR 2). For each association, the number of cases, random effects pooled effect size, 95% confidence intervals (CIs), heterogeneity, 95% prediction interval (PrI), small-study effect, and excess significance bias were recalculated to determine the evidence level. We identified 33 meta-analyses describing 58 dietary factors associated with ESCC and 29 meta-analyses describing 38 dietary factors associated with EAC. There was convincing evidence regarding the association of 2 dietary factors (areca nut and high alcohol) with the risk of ESCC. There was highly suggestive evidence regarding the association of only 1 dietary factor (healthy pattern) with the risk of ESCC. There was suggestive evidence regarding the association of 11 dietary factors with the risk of ESCC, including fruit, citrus fruit, vegetables, pickled vegetables, maté tea, moderate alcohol, hot beverages and foods, hot tea, salt, folate, and vitamin B6. There was convincing evidence regarding the association of one dietary factor (vitamin B6) with the risk of EAC. There was suggestive evidence regarding the association of 4 dietary factors with the risk of EAC, including processed meat, dietary fibre, carbohydrate, and vitamin B12. The convincing evidence regarding the associations between dietary factors and the risks of ESCC and EAC remained robust in sensitivity analyses. This umbrella review highlighted convincing evidence regarding the associations of areca nut and high alcohol with a higher risk of ESCC. Additionally, an association between vitamin B6 and a decreased risk of EAC was observed. Further research is needed to examine the dietary factors with weak evidence regarding their associations with ESCC and EAC.

A 64 × 128 3D-Stacked SPAD Image Sensor for Low-Light Imaging.

Low-light imaging capabilities are in urgent demand in many fields, such as security surveillance, night-time autonomous driving, wilderness rescue, and environmental monitoring. The excellent performance of SPAD devices gives them significant potential for applications in low-light imaging. This article presents a 64 (rows) × 128 (columns) SPAD image sensor designed for low-light imaging. The chip utilizes a three-dimensional stacking architecture and microlens technology, combined with compact gated pixel circuits designed with thick-gate MOS transistors, which further enhance the SPAD's photosensitivity. The configurable digital control circuit allows for the adjustment of exposure time, enabling the sensor to adapt to different lighting conditions. The chip exhibits very low dark noise levels, with an average DCR of 41.5 cps at 2.4 V excess bias voltage. Additionally, it employs a denoising algorithm specifically developed for the SPAD image sensor, achieving two-dimensional grayscale imaging under 6 × 10-4 lux illumination conditions, demonstrating excellent low-light imaging capabilities. The chip designed in this paper fully leverages the performance advantages of SPAD image sensors and holds promise for applications in various fields requiring low-light imaging capabilities.

Skilful probabilistic medium‐range precipitation and temperature forecasts over Vietnam for the development of a future dengue early warning system

AbstractDengue fever is a source of substantial health burden in Vietnam. Given the well‐established influence of temperature and precipitation on vector biology and disease transmission, predictions of meteorological variables, such as those issued by ECMWF as a world‐leading provider of global ensemble forecasts, are likely to be valuable model inputs to a future dengue early warning system. In the absence of established verification at municipal and regional scales, this study assesses the skill of rainy season (May–October) ensemble precipitation and 2‐m temperature retrospective forecasts over North and South Vietnam initialized for dates during the period 2001–2020, evaluated against the ERA5 reanalysis for the same period. Forecasts are found to be significantly skilful compared with both climatology and persistence for lead times up to 10 days, including for cumulative precipitation values considered against independent rain gauge data. Rank histograms demonstrate that ensembles generally avoid excessive bias and consistently positive CRPSS values indicate substantial skill for temperature and cumulative precipitation forecasts for all spatial scales considered, despite differences in rainy season characteristics between North and South Vietnam. This forecast reliability demonstrates that meteorological input data based on ECMWF ensemble forecasts would add appreciably more value to the development of a future dengue early warning system compared to reference forecasts like climatology or persistence. These results raise hope for further exploration of predictive skill for relevant meteorological variables, particularly focused on their downscaling to produce district‐level epidemiological forecasts for urban areas where dengue is most prevalent.

A Study on the Prediction Method of English Performance in Universities based on the Stacking Integrated Model

Students’ performance in higher education reflects their overall quality in higher education. By predicting the performance, students with greater learning problems can be screened out early and given appropriate guidance. To predict students’ performance in English, the knowledge information of courses, examination papers, and historical examination records are used to build a feature project of students’ examinations. Meanwhile, the features strongly correlated with their performance are filtered out. Then the next step of performance prediction is carried out. The results showed that a neural network long and short-term memory performance prediction model incorporating an attention mechanism was more effective than other models in predicting English performance in higher education. Further experiments found that the model reduced the error by 1.04% on the MAE metric, 0.53% on the RMSE metric, and increased its value by 4.12% on the R2 metric. Adding the new feature dataset led to better forecasting by the Att-LSTM model in all metrics. This indicated that the enhanced dataset temporality could improve the effectiveness of the Att-LSTM model in predicting English grades in higher education. The stacked integrated prediction model, by integrating multiple strong regressors, can avoid poor prediction and excessive overall bias due to one regressor and increase the soundness and prediction precision of the mode.

ABO and Rhesus blood groups and multiple health outcomes: an umbrella review of systematic reviews with meta-analyses of observational studies

BackgroundNumerous studies have been conducted to investigate the relationship between ABO and Rhesus (Rh) blood groups and various health outcomes. However, a comprehensive evaluation of the robustness of these associations is still lacking.MethodsWe searched PubMed, Web of Science, Embase, Scopus, Cochrane, and several regional databases from their inception until Feb 16, 2024, with the aim of identifying systematic reviews with meta-analyses of observational studies exploring associations between ABO and Rh blood groups and diverse health outcomes. For each association, we calculated the summary effect sizes, corresponding 95% confidence intervals, 95% prediction interval, heterogeneity, small-study effect, and evaluation of excess significance bias. The evidence was evaluated on a grading scale that ranged from convincing (Class I) to weak (Class IV). We assessed the certainty of evidence according to the Grading of Recommendations Assessment, Development, and Evaluation criteria (GRADE). We also evaluated the methodological quality of included studies using the A Measurement Tool to Assess Systematic Reviews (AMSTAR). AMSTAR contains 11 items, which were scored as high (8–11), moderate (4–7), and low (0–3) quality. We have gotten the registration for protocol on the PROSPERO database (CRD42023409547).ResultsThe current umbrella review included 51 systematic reviews with meta-analysis articles with 270 associations. We re-calculated each association and found only one convincing evidence (Class I) for an association between blood group B and type 2 diabetes mellitus risk compared with the non-B blood group. It had a summary odds ratio of 1.28 (95% confidence interval: 1.17, 1.40), was supported by 6870 cases with small heterogeneity (I2 = 13%) and 95% prediction intervals excluding the null value, and without hints of small-study effects (P for Egger’s test > 0.10, but the largest study effect was not more conservative than the summary effect size) or excess of significance (P < 0.10, but the value of observed less than expected). And the article was demonstrated with high methodological quality using AMSTAR (score = 9). According to AMSTAR, 18, 32, and 11 studies were categorized as high, moderate, and low quality, respectively. Nine statistically significant associations reached moderate quality based on GRADE.ConclusionsOur findings suggest a potential relationship between ABO and Rh blood groups and adverse health outcomes. Particularly the association between blood group B and type 2 diabetes mellitus risk.

The maternal factors associated with infant low birth weight: an umbrella review

BackgroundIn this umbrella review, we systematically evaluated the evidence from meta-analyses and systematic reviews of maternal factors associated with low birth weight.MethodsPubMed, Scopus, and Web of Science were searched to identify all relevant published studies up to August 2023. We included all meta-analysis studies (based on cohort, case-control, cross-sectional studies) that examined the association between maternal factors (15 risk factors) and risk of LBW, regardless of publication date. A random-effects meta-analysis was conducted to estimate the summary effect size along with the 95% confidence interval (CI), 95% prediction interval, and heterogeneity (I2) in all meta-analyses. Hedges’ g was used as the effect size metric. The effects of small studies and excess significance biases were assessed using funnel plots and the Egger’s test, respectively. The methodological quality of the included studies was assessed using the AMSTAR 2 tool.ResultsWe included 13 systematic Review with 15 meta-analysis studies in our study based on the inclusion criteria. The following 13 maternal factors were identified as risk factors for low birth weight: crack/cocaine (odds ratio [OR] 2.82, 95% confidence interval [CI] 2.26–3.52), infertility (OR 1.34, 95% CI 1.2–1.48), smoking (OR 2.00, 95% CI 1.76–2.28), periodontal disease (OR 2.41, 95% CI 1.67–3.47), depression (OR 1.84, 95% CI 1.34–2.53), anemia (OR 1.32, 95% CI 1.13–1.55), caffeine/coffee (OR 1.34, 95% CI 1.14–1.57), heavy physical workload (OR 1.87, 95% CI 1.00-3.47), lifting ≥ 11 kg (OR 1.59, 95% CI 1.02–2.48), underweight (OR 1.79, 95% CI 1.20–2.67), alcohol (OR 1.23, 95% CI 1.04–1.46), hypertension (OR 3.90, 95% CI 2.73–5.58), and hypothyroidism (OR 1.40, 95% CI 1.01–1.94). A significant negative association was also reported between antenatal care and low birth weight.ConclusionsThis umbrella review identified drug use (such as crack/cocaine), infertility, smoking, periodontal disease, depression, caffeine and anemia as risk factors for low birth weight in pregnant women. These findings suggest that pregnant women can reduce the risk of low birth weight by maintaining good oral health, eating a healthy diet, managing stress and mental health, and avoiding smoking and drug use.

Mental and physical health morbidity among people in prisons: an umbrella review

People who experience incarceration are characterised by poor health profiles. Clarification of the disease burden in the prison population can inform service and policy development. We aimed to synthesise and assess the evidence regarding the epidemiology of mental and physical health conditions among people in prisons worldwide. In this umbrella review, five bibliographic databases (Web of Science, PubMed, PsycINFO, Embase, and Global Health) were systematically searched from inception to identify meta-analyses published up to Oct 31, 2023, which examined the prevalence or incidence of mental and physical health conditions in general prison populations. We excluded meta-analyses that examined health conditions in selected or clinical prison populations. Prevalence data were extracted from published reports and study authors were contacted for additional information. Estimates were synthesised and stratified by sex, age, and country income level. The robustness of the findings was assessed in terms of heterogeneity, excess significance bias, small-study effects, and review quality. The study protocol was pre-registered with PROSPERO, CRD42023404827. Our search of the literature yielded 1909 records eligible for screening. 1736 articles were excluded and 173 full-text reports were examined for eligibility. 144 articles were then excluded due to not meeting inclusion criteria, which resulted in 29 meta-analyses eligible for inclusion. 12 of these were further excluded because they examined the same health condition. We included data from 17 meta-analyses published between 2002 and 2023. In adult men and women combined, the 6-month prevalence was 11·4% (95% CI 9·9-12·8) for major depression, 9·8% (6·8-13·2) for post-traumatic stress disorder, and 3·7% (3·2-4·1) for psychotic illness. On arrival to prison, 23·8% (95% CI 21·0-26·7) of people met diagnostic criteria for alcohol use disorder and 38·9% (31·5-46·2) for drug use disorder. Half of those with major depression or psychotic illness had a comorbid substance use disorder. Infectious diseases were also common; 17·7% (95% CI 15·0-20·7) of people were antibody-positive for hepatitis C virus, with lower estimates (ranging between 2·6% and 5·2%) found for hepatitis B virus, HIV, and tuberculosis. Meta-regression analyses indicated significant differences in prevalence by sex and country income level, albeit not consistent across health conditions. The burden of non-communicable chronic diseases was only examined in adults aged 50 years and older. Overall, the quality of the evidence was limited by high heterogeneity and small-study effects. People in prisons have a specific pattern of morbidity that represents an opportunity for public health to address. In particular, integrating prison health within the national public health system, adequately resourcing primary care and mental health services, and improving linkage with post-release health services could affect public health and safety. Population-based longitudinal studies are needed to clarify the extent to which incarceration affects health. Research Foundation-Flanders, Wellcome Trust, National Institutes of Health.

Modelling atmospheric behaviour over southern West Africa using RegCM 4.7.1: Case assessment of relative humidity and zonal wind profiles based on the 2016 DACCIWA summertime field campaign

In this paper, we present an analysis of summertime atmospheric simulation (June–July 2016) for southern West Africa (sWA) using the RegCM 4.7.1 regional climate model to describe the atmospheric behaviour over the region, and also engage comparisons between the modelled data and observed upper air data acquired during the DACCIWA (Dynamics–Aerosol–Chemistry–Cloud Interactions in West Africa) field campaign period. First, assessments of relative humidity and zonal wind profiles were made for selected coastal and inland stations, to infer the relative vertical and temporal atmospheric differences for both locations. Thereafter, the model’s performance was evaluated, capturing an excessive wet bias in RH profiles of the model with accompanying reduced zonal winds at the Tropical Easterly Jet (TEJ) region and thus produces excessive upper tropospheric cloud liquid water content. Also, in the lower troposphere (particularly, the monsoon layer), RegCM 4.7.1 model captures adequate spatial differences in both RH and zonal wind profiles along the coast and inland. We judge this outcome to be a valuable contribution on the path to rendering RegCM4 a good tool for simulating atmospheric and climate dynamics in sWA.

Environmental Risk Factors, Protective Factors, and Biomarkers for Hearing Loss: An Umbrella Review.

We aimed to investigate the potential environmental risk factors, protective factors, and biomarkers of hearing loss (HL), and establish a hierarchy of evidence. Embase, PubMed, Cochrane Library, and Web of Science electronic database from inception to June 1, 2023. We included meta-analyses of observational studies of associations between HL and environmental risk factors, protective factors, or biomarkers. We calculated summary effect estimates, 95% confidence interval, heterogeneity I2 statistic, 95% prediction interval, small study effects, and excess significance biases. Of the 9211 articles retrieved, 60 eligible articles were included. The 60 eligible articles identified 47 potential environmental risk and protective factors (N = 4,123,803) and 46 potential biomarkers (N = 173,701). Evidence of association was convincing (class I) for rheumatoid arthritis (RA) and every 1 cm increase in height. Evidence of association was highly suggestive (class II) for human immunodeficiency virus (HIV), diabetes, cumulative noise exposure (CNE), smoking, congenital cytomegalovirus (CMV) infection, combined exposure to organic solvents and noise, non-Gaussian noise exposure, each 1 kg increase in birth weight, noise exposure, and alopecia areata (AA). In this umbrella review, RA, every 1 cm increase in height, HIV, diabetes, CNE, smoking, congenital CMV infection, combined exposure to organic solvents and noise, non-Gaussian noise exposure, each 1 kg increase in birth weight, noise exposure, and AA were strongly associated with HL.

Quantifying the association of sperm DNA fragmentation with assisted reproductive technology outcomes: An umbrella review.

Systematic reviews and meta-analyses are instrumental in shaping clinical practice. However, their findings can sometimes be marred by discrepancies and potential biases, thereby diluting the strength of the evidence presented. Umbrella reviews serve to comprehensively assess and synthesise these reviews, offering a clearer insight into the quality of the evidence presented. In the context of the relationship between sperm DNA fragmentation (SDF) and assisted conception outcomes, there is a divergence in the literature. Some reviews suggest a clear cause-and-effect linkage, whereas others present conflicting or inconclusive results. In this umbrella review we aimed to synthesise the evidence collated in systematic reviews and meta-analyses summarising the association of SDF with assisted reproductive technology (ART) outcomes. After preregistration (https://doi.org/10.17605/OSF.IO/6JHDP), we performed a comprehensive search of the PubMed, Scopus, Cochrane Library, Web of Science and Embase databases. We conducted a search for systematic reviews on the association between SDF and ART without any restrictions on language or publication date. Systematic reviews and meta-analyses assessing the association between SDF and ART outcomes were eligible. We assessed the quality of the included reviews using AMSTAR 2 and ROBIS, and determined the degree of overlap of primary studies between reviews estimating the corrected covered area (CCA), adjusted for structural missingness. We evaluated the most recent reviews assessing the association of SDF with live birth, pregnancy, miscarriage, implantation, blastulation and fertilisation. The synthesis of evidence was harmonised across all included quantitative syntheses, re-estimating the odds ratio (eOR) in random-effects meta-analyses with 95% confidence intervals (95% CIs) and 95% prediction intervals (95% PIs). We categorised the evidence strength into convincing, highly suggestive, suggestive, weak or nonsignificant, according to the meta-analysis re-estimated P-value, total sample size, I2 statistic for heterogeneity, small study effect, excess significance bias and the largest study significance. We initially captured and screened 49 332 records. After excluding duplicate and ineligible articles, 22 systematic reviews, 15 of which were meta-analyses, were selected. The 22 reviews showed a moderate degree of overlap (adjusted CCA 9.2%) in their included studies (overall n = 428, with 180 unique studies). The 15 meta-analyses exhibited a high degree of overlap (adjusted CCA = 13.6%) in their included studies (overall n = 274, with 118 unique studies). AMSTAR 2 categorised the quality of evidence in 18 reviews as critically low and the quality of evidence in four reviews as low. ROBIS categorised all the reviews as having a high risk of bias. The re-estimated results showed that the association of SDF with live birth was weak in one and nonsignificant in four meta-analyses. Similarly, the association of SDF with pregnancy, miscarriage, implantation, blastulation and fertilisation was also weak or nonsignificant. The association of high SDF with different ART outcomes was also weak or nonsignificant for different interventions (IVF, ICSI and IUI) and tests. This umbrella review did not find convincing or suggestive evidence linking SDF with ART outcomes. Caution should be exercised in making any claims, policies or recommendations concerning SDF.

Junction-Optimized SPAD With 50.6% Peak PDP and 0.64 cps/μm2 DCR at 2 V Excess Bias Voltage in 130 nm CMOS

Junction-Optimized SPAD With 50.6% Peak PDP and 0.64 cps/μm² DCR at 2 V Excess Bias Voltage in 130 nm CMOS

Room temperature operation of germanium-silicon single-photon avalanche diode.

The ability to detect single photons has led to the advancement of numerous research fields1-11. Although various types of single-photon detector have been developed12, because of two main factors-that is, (1) the need for operating at cryogenic temperature13,14 and (2) the incompatibility with complementary metal-oxide-semiconductor (CMOS)fabrication processes15,16-so far, to our knowledge, only Si-based single-photon avalanche diode (SPAD)17,18 has gained mainstream success and has been used in consumer electronics. With the growing demand to shift the operation wavelength from near-infrared to short-wavelength infrared (SWIR)for better safety and performance19-21, an alternative solution is required because Si has negligible optical absorption for wavelengths beyond 1 µm. Here we report a CMOS-compatible, high-performing germanium-silicon SPAD operated at room temperature, featuring a noise-equivalent power improvement over the previous Ge-based SPADs22-28 by 2-3.5 orders of magnitude. Key parameters such as dark count rate, single-photon detection probability at 1,310 nm, timing jitter, after-pulsing characteristic time and after-pulsing probability are, respectively, measured as 19 kHz µm-2, 12%, 188 ps, ~90 ns and <1%, with a low breakdown voltage of 10.26 V and a small excess bias of 0.75 V. Three-dimensional point-cloud images are captured with direct time-of-flight technique as proof of concept. This work paves the way towards using single-photon-sensitive SWIR sensors, imagers and photonic integrated circuits in everyday life.

Adaptive Point-Line Fusion: A Targetless LiDAR-Camera Calibration Method with Scheme Selection for Autonomous Driving.

Accurate calibration between LiDAR and camera sensors is crucial for autonomous driving systems to perceive and understand the environment effectively. Typically, LiDAR-camera extrinsic calibration requires feature alignment and overlapping fields of view. Aligning features from different modalities can be challenging due to noise influence. Therefore, this paper proposes a targetless extrinsic calibration method for monocular cameras and LiDAR sensors that have a non-overlapping field of view. The proposed solution uses pose transformation to establish data association across different modalities. This conversion turns the calibration problem into an optimization problem within a visual SLAM system without requiring overlapping views. To improve performance, line features serve as constraints in visual SLAM. Accurate positions of line segments are obtained by utilizing an extended photometric error optimization method. Moreover, a strategy is proposed for selecting appropriate calibration methods from among several alternative optimization schemes. This adaptive calibration method selection strategy ensures robust calibration performance in urban autonomous driving scenarios with varying lighting and environmental textures while avoiding failures and excessive bias that may result from relying on a single approach.

Enhancing the bond strength of magnetron-sputtered copper layers on polyimide and polyether ether ketone surfaces through surface modification

This study explores the fabrication of composites involving polyimide (PI) and polyether ether ketone (PEEK) resins with Cu using chemical treatment and sandblasting, followed by plasma cleaning in a vacuum environment charged with Ar. To enhance the bonding strength of Cu to PI and PEEK, vacuum magnetron sputtering was used to deposit an intermediate transition layer of titanium and a plated seed layer of Cu onto the resin. For PI/copper composites, the copper layer’s highest bonding strength was achieved through sandblasting and plasma cleaning for 150 s at a bias voltage of 100 V. For PEEK/Cu composites, the optimal bonding strength of the copper layer was observed after 80 s of plasma cleaning. Surface roughness is important in the bonding strength of the copper layer. Additionally, the Ti transition layer strengthens bonding forces between Cu and both PI and PEEK. X-ray photoelectron spectroscopy revealed Ti–O bond formation with oxygen in the resins and Ti–C bonds within the carbon, indicating chemical interactions that bolstered Cu adhesion to resins. Adjusting the bias voltage had varying effects on the bonding strength of resin/Cu. For PI/Cu, the bonding force decreased with increasing bias voltage (20–150 V) owing to excessive bias voltage causing surface defects on the plated Cu layer, which reduced the density of the plated Cu layer. Conversely, the PEEK/Cu bonding force initially increased with increasing bias voltage due to enhanced surface bombardment. Beyond an optimal point, the bonding force in PEEK/Cu decreased due to unfavorable effects on layer density.

Interventions for psychiatric disorders among university students: An umbrella review of systematic reviews and meta-analyses

BackgroundMental disorders are considered to be the main reason for the increase of the disease burden. College students seem to be more vulnerable to the adverse effects of stress, which makes them more at risk of suffering from mental disorders. This umbrella review aimed to evaluate the credibility of published evidence regarding the effects of interventions on mental disorders among university students. MethodsTo identify systematic reviews and meta-analyses investigating the effects of interventions on mental disorders in the university student population, extensive searches were carried out in databases including PubMed, Embase, and the Cochrane Database, spanning from inception to July 21, 2023. Subsequently, a thorough reanalysis of crucial parameters such as summary effect estimates, 95 % confidence intervals, heterogeneity I2 statistic, 95 % prediction intervals, small-study effects, and excess significance bias was performed for each meta-analysis found. ResultsNineteen articles involving 74 meta-analyses were included. Our grading of the current evidence showed that interventions based on exercise, Cognitive-behavioural Intervention (CBI), mindfulness-based interventions (MBI), and other interventions like mood and anxiety interventions (MAI) were effective whereas exercise intervention had the highest effect size for both depression and anxiety among university students. However, the credibility of the evidence was weak for most studies. Besides, suggestive evidence was observed for the positive effects of CBI on sleep disturbance(SMD: -0.603, 95 % CI: -0.916, -0.290; P-random effects<0.01) and MAI on anxiety (Hedges'g = -0.198, 95 % CI: -0.302, -0.094; P-random effects<0.01). ConclusionBased on our findings, it appears that exercise interventions, CBI, and MAI have the potential to alleviate symptoms related to mental disorders. Despite the overall weak credibility of the evidence and the strength of the associations, these interventions offer a promising avenue for further exploration and research in the future. More high-quality randomized controlled trials should be taken into account to verify the effects of these interventions on various mental disorders.

Care intervention on psychological outcomes among patients admitted to intensive care unit: an umbrella review of systematic reviews and meta-analyses

BackgroundNumerous studies have explored care interventions to improve the psychological outcome of intensive care unit (ICU) patients, but inconclusive evidence makes it difficult for decision-makers, managers, and clinicians to get familiar with all available literature and find appropriate interventions. This umbrella review aimed to analyze the relationship between care intervention and psychological outcomes of ICU patients based on existing systematic reviews.MethodsAn umbrella review of evidence across systematic reviews and meta-analyses published between 1987 and 2023 was undertaken. We systematically searched reviews that examined the association between care intervention and the improvement of adverse psychological outcomes in ICU patients using PubMed, EMBASE, Web of Science, Cochrane Library, and manual reference screening. The measurement tool (AMSTAR 2) was applied to evaluate the methodological quality of included studies. The excess significance bias, between-study heterogeneity expressed by I2, small-study effect, and evidence class were estimated.ResultsA total of 5110 articles were initially identified from the search databases and nine of them were included in the analysis. By applying standardized criteria, only weak evidence was observed in 13 associations, even though most included reviews were of moderate to high methodological quality. These associations pertained to eight interventions (music therapy, early rehabilitation, post-ICU follow-up, ICU diary, information intervention, preoperative education, communication and psychological support, surrogate decision-making) and five psychological outcomes (post-intensive care syndrome, transfer anxiety, post-traumatic stress disorder, anxiety, and depression). Weak or null association was shown among the rest of the associations (e.g., weak association between music therapy and maternal anxiety or stress level).ConclusionsThe evidence of these eight supporting interventions to improve the adverse psychological outcomes of ICU patients and caregivers was weak. Data from more and better-designed studies with larger sample sizes are needed to establish robust evidence.