Tag: statistics

IEEE Trans Image Process. 2021 May 4;PP. doi: 10.1109/TIP.2021.3076310. Online ahead of print.

ABSTRACT

Inpainting arbitrary missing regions is challenging because learning valid features for various masked regions is nontrivial. Though U-shaped encoder-decoder frameworks have been witnessed to be successful, most of them share a common drawback of mask unawareness in feature extraction because all convolution windows (or regions), including those with various shapes of missing pixels, are treated equally and filtered with fixed learned kernels. To this end, we propose our novel mask-aware inpainting solution. Firstly, a Mask-Aware Dynamic Filtering (MADF) module is designed to effectively learn multi-scale features for missing regions in the encoding phase. Specifically, filters for each convolution window are generated from features of the corresponding region of the mask. The second fold of mask awareness is achieved by adopting Point-wise Normalization (PN) in our decoding phase, considering that statistical natures of features at masked points differentiate from those of unmasked points. The proposed PN can tackle this issue by dynamically assigning point-wise scaling factor and bias. Lastly, our model is designed to be an end-to-end cascaded refinement one. Supervision information such as reconstruction loss, perceptual loss and total variation loss is incrementally leveraged to boost the inpainting results from coarse to fine. Effectiveness of the proposed framework is validated both quantitatively and qualitatively via extensive experiments on three public datasets including Places2, CelebA and Paris StreetView.

PMID:33945479 | DOI:10.1109/TIP.2021.3076310

Expert Rev Respir Med. 2021 May 4. doi: 10.1080/17476348.2021.1925546. Online ahead of print.

ABSTRACT

OBJECTIVES: The questions remained if mortality benefits with dexamethasone seen in patients with coronavirus disease 2019 (COVID-19) also extend to other systemic corticosteroids such as methylprednisolone. This article presents a meta-analysis of randomized controlled trials (RCTs) to ascertain if methylprednisolone can be recommended for use in patients with COVID-19 to prevent deaths.

METHODS: Systematic literature search was performed in PubMed, Scopus, Cochrane Central Register of Controlled Trials, and preprint servers until 13^th April 2021. The outcome of interest was all-cause mortality. The random-effects model for the meta-analysis was utilized to estimate the pooled odds ratio (OR) at 95% confidence intervals (CI).

RESULTS: Five RCTs were included in the meta-analysis. The pooled OR for all-cause mortality was 0.64 (95% CI: 0.29 -1.43, n=652) comparing methylprednisolone with the control, indicating no mortality benefits. A similar finding was noted with a sub-group analysis including four trials that used low-dose methylprednisolone. However, the only trial that administered high doses of methylprednisolone indicated a statistically significant mortality benefit (OR 0.08, 95% CI: 0.02-0.42).

CONCLUSIONS: A short duration (3 to 5 days) pulse therapy of high-dose methylprednisolone can be a promising alternative to the low-dose dexamethasone therapy in severely ill patients with COVID-19 to prevent deaths.

PMID:33945381 | DOI:10.1080/17476348.2021.1925546

Expert Rev Respir Med. 2021 May 4. doi: 10.1080/17476348.2021.1923482. Online ahead of print.

ABSTRACT

BACKGROUND: Different scoring systems (A2DS2, AISAPS, ISAN) have been designed to predict the risk of in-hospital stroke-associated pneumonia (SAP). Studies have assessed the accuracy of these scores for predicting SAP. We performed this meta-analysis to consolidate the evidence on the predictive accuracies for SAP of the A2DS2, AISAPS, and ISAN scores.

MATERIALS AND METHODS: We conducted a systematic search for all studies reporting the SAP predictive accuracy of A2DS2, AISAPS, or ISAN scores in the databases of PubMed Central, SCOPUS, MEDLINE, Embase, and Cochrane from inception until December 2020. We used the STATA software for the meta-analysis.

RESULTS: : We included 19 studies with 35 849 patients. The pooled score sensitivities were 78% (95% CI, 71%-83%) for A2DS2, 79% (95% CI, 77%-81%) for AISAPS, and 79% (95% CI, 77%-81%) for ISAN. The pooled score specificities were 73% (95% CI, 65%-80%) for A2DS2, 74% (95% CI, 69%-79%) for AISAPS, and 74% (95% CI, 69%-79%) for ISAN. We found significant heterogeneity for all the scoring systems based on the chi-square test results and an I² statistic > 75%. We performed meta-regression to explore the source of heterogeneity and found that patient selection (p<0.05) and reference standards (p<0.05) in the sensitivity model, index test standards (p<0.05), flow and timing of tests (p<0.01) in the specificity model, and mean age (p<0.001) in the joint model were the source of heterogeneity.

CONCLUSIONS: To summarize, we found that A2S2, AISAPS and ISAN have moderate predictive accuracy for SAP with A2S2 having a stable cut-off value.

PMID:33945394 | DOI:10.1080/17476348.2021.1923482

Hum Vaccin Immunother. 2021 May 4:1-9. doi: 10.1080/21645515.2021.1914804. Online ahead of print.

ABSTRACT

Objective: A bibliometric analysis was conducted to build an all-inclusive view of the status of research on hepatitis A virus (HAV) for facilitating researchers, health professionals, and policymakers to understand the characteristics of research output in this particular domain.Methods: A comprehensive search was conducted in the Web of Science database. The obtained data were exported into Microsoft Excel 2019, OriginPro 2018 and VOSviewer software for windows.Results: From 1985 to 2019, a total of 5,950 studies on HAV were published, with an overall h-index of 105, and 90,350 total citations. The most cited article on HAV was “Classification of chronic viral hepatitis: a need for reassessment” authored by Scheuer in the Journal of Hepatology with a total of 1,121 citations. The most cited article on HAV vaccine was “A controlled trial of a formalin-inactivated hepatitis A vaccine in healthy children” by Werzberger et al. in the New England Journal of Medicine with 401 citations. The most frequent year of publication was 2019 (n = 250). The largest number of studies were funded by the United States Department of Health Human Services (n = 199). The organization with the highest number of publications was the United States Centers for Disease Control and Prevention (n = 228). The United State of America (n = 1,500) was the country with the most publications. ‘Vaccine’ was the leading journal with 299 publications.Conclusions: The highest numbers of studies were published in developed countries. There is a clear need for interdisciplinary research approaches to evaluate and intervene in HAV endemic areas.

PMID:33945397 | DOI:10.1080/21645515.2021.1914804

J Air Waste Manag Assoc. 2021 May 4. doi: 10.1080/10962247.2021.1923586. Online ahead of print.

ABSTRACT

Light-duty gasoline vehicle (LDGV) tailpipe emission rates can be quantified based on pollutant concentrations measured using portable emission measurement systems (PEMS). Emission rates depend on exhaust flow. For simplified and micro-PEMS, exhaust flow is inferred from engine mass air flow (MAF) and air-to-fuel ratio. For many LDGVs, MAF is broadcast via the on-board diagnostic (OBD) interface. For some vehicles, only indirect indicators of MAF are broadcast. In such cases, MAF can be estimated using the speed-density method (SDM). The SDM requires an estimate of the engine volumetric efficiency (VE), which is the ratio of actual to theoretical MAF. VE is affected by intra-vehicle variability in the engine load and inter-vehicle variability in engine characteristics (e.g., the type of valvetrain). The suitability of SDM-based estimates of MAF in conjunction with simplified and micro-PEMS has not been adequately evaluated. Therefore, the objectives are to: (1) quantify VE accounting for intra- and inter-vehicle variability; and (2) evaluate the accuracy of SDM-based vehicle emission rate estimation approaches. Seventy-seven naturally-aspirated LDGVs were measured using PEMS. For each vehicle, VE was estimated using three approaches: (1) constant VE calibrated to actual fuel use; (2) average estimates of VE for Vehicle Specific Power modes imputed from OBD data; and (3) modeled VE using multilinear regression (MLR). The MLR models were developed based on engine load and engine characteristics. The best model was selected based on various statistical diagnostics. When engines were under load, variability in VE was most sensitive to variations in engine load. During idling, VE differed between engines depending on engine characteristics. The constant and modeled VE estimation approaches enable the accurate estimation of microscale and mesoscale emission rates, with errors typically within ±10% compared to values imputed from OBD data. Thus, accurate emission rates can be obtained from simplified and micro-PEMS. Implications StatementSimplified and micro portable emission measurement systems (PEMS) enable widespread measurement of vehicle exhaust emission. As a cost saving measure, they estimate exhaust flow indirectly rather than via measurement, typically based on engine mass air flow (MAF). For some vehicles, MAF is not reported by the on-board diagnostic (OBD) system but can be inferred from other reported variables and volumetric efficiency (VE). However, VE is typically proprietary. Methods demonstrated here for estimating VE enable accurate quantification of emission rates, thereby enabling use of these PEMS for policy-relevant applications such as technology assessments, trends analysis, and emissions inventories.

PMID:33945402 | DOI:10.1080/10962247.2021.1923586

Genet Test Mol Biomarkers. 2021 May 4. doi: 10.1089/gtmb.2020.0334. Online ahead of print.

ABSTRACT

Aim: The aim of this study was to explore the possible associations between single nucleotide polymorphisms (SNPs) and DNA methylation levels of seven genes in the inflammatory response pathway with susceptibility to chronic periodontitis (CP) among the Uighur population of the Xinjiang Autonomous Region of China. Methods: A total of 444 eligible subjects (279 CP patients and 165 healthy controls) were enrolled in the study. Genomic DNA was obtained from gingival tissue for genotyping eight SNPs and performing methylation measurements of seven genes. Results: SNP rs2070745 in the formyl peptide receptor 1 (FPR1) gene achieved statistical significance in the standard allelic association analysis for CP (p = 0.02). The frequency of the rs2070745 minor allele G was higher in the cases than in controls (0.367 vs. 0.291). Additionally, rs2070745 was significantly associated with CP under the dominant genetic model (p = 0.03). Using logistic regression analysis, rs2070745 was found to be consistently associated with CP under the additive dominant model, and this association remained significant after covariates were taken into account [odds ratio (OR) = 1.49 (1.09-2.05), p = 0.014; OR = 1.58 (1.04-2.40), p = 0.031, respectively]. No significant gene-gene interactions were identified. Although we did not find a polymorphism in interleukin 6 (IL6) associated with CP in our study, the methylation level of a CpG island region located within the promoter region of IL6 was significantly less in CP patients compared with controls (p < 0.05). Conclusions: The genetic polymorphism rs2070745 in FPR1 and the methylation level of the promoter region of IL6 might be associated with CP in the Uighur population of China.

PMID:33945309 | DOI:10.1089/gtmb.2020.0334

Neuromodulation. 2021 May 4. doi: 10.1111/ner.13401. Online ahead of print.

ABSTRACT

BACKGROUND: Patients with pudendal neuralgia (PN) experience long-lasting chronic pain, hyperalgesia, and comorbid emotional disorders, such as depression and anxiety. Treatment via conventional pulsed radiofrequency (PRF) current carries a significantly high rate of failure.

OBJECTIVE: To determine the safety and clinical efficacy of high-voltage, long-duration PRF application to the pudendal nerve in patients with PN.

STUDY DESIGN: Observational retrospective design, self before-after controlled clinical trial.

MATERIALS AND METHODS: We analyzed the records of 70 patients of our hospital with diagnosed PN. Treatment consisted of PRF application to the pudendal nerve, using computed tomography guidance to target the pudendal nerve at the level of the ischial spine or ischial tuberosity of the affected side. PRF was applied with the following parameters: temperature 42°C, frequency 2 Hz, pulse width 20 ms, field intensity ramped gradually from 40 to 90 V, duration 900 sec. The therapeutic effect was evaluated by collecting patient scores for the visual analog scale (VAS), SF-36 health survey questionnaire (SF-36), and patient health questionnaire (PHQ-9) before treatment and at 1-, 4-, and 12-week follow-ups after PRF treatment. Data were analyzed by paired t-test with p < 0.05 considered to be statistically significant.

RESULTS: VAS, SF-36, and PHQ-9 scores at 1, 4, and 12 weeks after high-voltage long-duration PRF treatment were significantly improved relative to their respective pretreatment baseline scores (p < 0.05 for all). The effective rate at 12 weeks after high-voltage long-duration PRF was up to 88.6%.

LIMITATIONS: A small sample size and lack of a control group.

CONCLUSIONS: High-voltage long-duration PRF provided significant short-term (at least 12 weeks) pain relief to most patients with PN; it also improved subjective measures of depression and quality of life over the same duration of time.

PMID:33945192 | DOI:10.1111/ner.13401

Australas J Ageing. 2021 May 4. doi: 10.1111/ajag.12950. Online ahead of print.

ABSTRACT

OBJECTIVES: To assess the impact of a Consumer Directed Care (CDC) model of service delivery on the quality of life of older people receiving home care packages.

METHODS: Quality of life was assessed using validated instruments. The relationship between quality of life and length of time exposed to CDC was examined using descriptive statistical and multivariate regression analyses.

RESULTS: Consenting older adults (n = 150) in receipt of home care packages participated. Quality of life and capability scores were higher for older people in receipt of a CDC model of service delivery for <12 months compared to those receiving the model of care for longer, although this difference was not statistically significant. However, older people with more recent exposure to CDC indicated a stronger capability to do things that made them feel valued.

CONCLUSION: Extended longitudinal follow-up is needed to facilitate a detailed examination of the relationship between the evolution of CDC and its longer-term influences on quality of life.

PMID:33945198 | DOI:10.1111/ajag.12950

Orthop Surg. 2021 May 4. doi: 10.1111/os.12960. Online ahead of print.

ABSTRACT

OBJECTIVE: To evaluate the clinical outcomes of oblique lumbar interbody fusion (OLIF) in conjunction with unilateral pedicle screw fixation (UPSF) via the Wiltse approach in treating degenerative lumbar scoliosis (DLS).

METHODS: The article is a retrospective analysis. Twelve patients with DLS who underwent combined OLIF and UPSF between July 2017 and December 2018 were included. The study included 2 male and 10 female patients, with a mean age at the time of the operation of 67.2 ± 9.1 years. The surgical characteristics and complications were evaluated. The clinical and radiological data such as the correction of deformity, coronal and sagittal profile were analyzed.

RESULTS: The mean follow-up time of the study was 26.8 ± 1.8 months. At the final follow-up, all patients who underwent combined OLIF and UPSF achieved statistically significant improvements in coronal Cobb angle (from 19.6° ± 4.8° to 6.9° ± 3.8°, P < 0.01), distance between the C7 plumb line and central sacral vertebral line (from 2.5 ± 1.7 cm to 0.9 ± 0.6 cm, P < 0.01), sagittal vertebral axis (from 4.3 ± 4.3 cm to 1.5 ± 1.0 cm, P = 0.03), lumbar lordosis (from 29.4° ± 8.6° to 40.8° ± 5.8°, P < 0.01), pelvic tilt (from 27.6° ± 10.8° to 18.3° ± 7.0°, P < 0.01), pelvic incidence-lumbar lordosis mismatch (from 23.3° ± 10.5° to 11.9° ± 8.4°, P < 0.01), and cross-sectional area of the dural sac (from 87.33 ± 39.41 mm² to 124.70 ± 39.26 mm² , P < 0.01). The visual analogue score for back and leg pain and Oswestry Disability Index of all patients significantly improved postoperatively (P < 0.01). One case of lumbar plexus injury was found after surgery. During the follow-up period, one patient had cage subsidence. A fusion rate of 100% and good positioning of the pedicle screws were achieved in all patients at the final follow-up.

CONCLUSION: OLIF in conjunction with UPSF is a safe and effective minimally invasive procedure for correcting both coronal and sagittal deformities, as it results in an improved quality of life in patients with DLS.

PMID:33945217 | DOI:10.1111/os.12960

J Morphol. 2021 May 4. doi: 10.1002/jmor.21365. Online ahead of print.

ABSTRACT

The discovery of cryptic biodiversity has blossomed under the advancements of genetic techniques, but species identification via morphology remains crucial to effective conservation efforts. In this study, we tested the use of continuous cranial shape variation in distinguishing the two living species of Mecistops: the West African slender-snouted crocodile (M. cataphractus) and the Central African slender-snouted crocodile (M. leptorhynchus). Using a combination of geometric morphometric characters and ratios of linear measurements, we identified statistically significant variation in cranial bone and overall skull shape of mature individuals that corroborates existing molecular and discrete morphological evidence for two distinct, extant species within Mecistops. Specifically, variation in the shape of the nasal appears particularly diagnostic, while ratios involving metrics of snout length to snout width at the premaxillary notch offer distinguishing features easily measured in the field. Because of the complementary results and applications of the morphometric and cranial ratio analyses, we argue that both methodologies remain relevant to species identification. Moreover, we recommend continued cooperation between geneticists and morphologists in diagnosing species of conservation concern.

PMID:33945166 | DOI:10.1002/jmor.21365