Log Variance Research Articles

Trade liberalization, labor market power, and misallocation across firms: Evidence from China's WTO accession

This paper studies the impact of trade liberalization on the heterogeneity of labor market power among manufacturing firms, which is a potential source of misallocation. The model shows that heterogeneity of labor market power distorts the allocation of the factors of production, and the variance in the natural log of the markdown serves as a sufficient statistic to infer its negative impact on overall production efficiency. Using China's accession to the World Trade Organization (WTO) as a natural experiment, the empirical results suggest that lower input tariffs decrease the variance in the natural log of the markdown, which reflects the improvement in misallocation. In contrast, reductions in output tariffs have no significant effects.

Validating statistical properties of resilience indicators derived from simulated longitudinal performance measures of farmed animals

Resilience is commonly defined as the ability of an individual to be minimally affected or to quickly recover from a challenge. Improvement of animals’ resilience is a vital component of sustainable livestock production but has so far been hampered by the lack of established quantitative resilience measures. Several studies proposed that summary statistics of the deviations of an animal’s observed performance from its target performance trajectory (i.e., performance in the absence of challenge) may constitute suitable quantitative resilience indicators. However, these statistical indicators require further validation. The aim of this study was to obtain a better understanding of these resilience indicators in their ability to discriminate between different response types and their dependence on different response characteristics of animals, and data recording features. To this purpose, milk-yield trajectories of individual dairy cattle differing in resilience, without and when exposed to a short-term challenge, were simulated. Individuals were categorised into three broad response types (with individual variation within each type): Fully Resilient animals, which experience no systematic perturbation in milk yield after challenge, Non-Resilient animals whose milk yield permanently deviates from the target trajectory after challenge and Partially Resilient animals that experience temporary perturbations but recover. The following statistical resilience indicators previously suggested in the literature were validated with respect to their ability to discriminate between response types and their sensitivity to various response features and data characteristics: logarithm of mean of squares (LMS), logarithm of variance (LV), skewness (S), lag-1 autocorrelation (AC1), and area under the curve (AUC) of deviations. Furthermore, different methods for estimating unknown target trajectories were evaluated. All of the considered resilience indicators could distinguish between the Fully Resilient response type and either of the other two types when target trajectories were known or estimated using a parametric method. When the comparison was between Partially Resilient and Non-Resilient, only LMS, LV, and AUC could correctly rank the response types, provided that the observation period was at least twice as long as the perturbation period. Skewness was in general the least reliable indicator, although all indicators showed correct dependency on the amplitude and duration of the perturbations. In addition, all resilience indicators except for AC1 were robust to lower frequency of measurements. In general, parametric methods (quantile or repeated regression) combined with three resilience indicators (LMS, LV and AUC) were found the most reliable techniques for ranking animals in terms of their resilience.

Menstrual blood loss is an independent determinant of hemoglobin and ferritin levels in premenopausal blood donors.

To prevent blood donors from developing iron deficiency (ferritin <15 μg/L) and subsequent anemia (hemoglobin <120 g/L), blood services rely on information about known risk factors, including the donor's sex and age. For example, while Finnish women are able to donate whole blood with a minimum donation interval of 91 days, women in the 18 to 25-year-old age group are recommended to donate no more than once per year. Menstrual blood loss is not accounted for in blood donation interval recommendations, despite being a known risk factor of iron deficiency. We aim to investigate to what extent menstrual bleeding is associated with ferritin and hemoglobin levels in female blood donors, and quantify the association of other menstruation-related variables not currently accounted for by blood services (i.e., use of hormonal contraception, heavy menstrual bleeding) with iron deficiency or anemia. The study population consisted of 473 premenopausal and 491 postmenopausal Dutch whole blood donors. Exclusion criteria were current pregnancy, BMI ≥50, ferritin ≥200, pictorial blood assessment chart (PBAC) ≥400, and age <18 or ≥70 years. Menstrual blood loss was quantified using a PBAC, a semiquantitative method to evaluate the number of used menstrual products and the degree of staining. We identified predictors of log(ferritin)/hemoglobin and iron deficiency/anemia using Bayesian linear and logistic regression models and quantified the average percentage of variance in log(ferritin) and hemoglobin explained by the covariates. Menstrual blood loss accounted for most of the explained variance in hemoglobin (8%) and second only to the number of days since last donation for ferritin (8%). Heavy menstrual bleeding (PBAC ≥150, OR = 3.56 [1.45-8.85], prevalence 13%) was associated with anemia, and use of levonorgestrel-releasing intrauterine device was negatively associated with iron deficiency (OR = 0.06 [0.01-0.44]). After statistical control for menstrual blood loss, age was not associated with iron status. Menstrual blood loss and blood donation were the most important determinants of iron status in premenopausal women. Thus, results suggest that accounting for menstrual blood loss in donation interval guidelines may benefit blood donors.

Robust Parameter Design on Dual Stochastic Response Models With Constrained Bayesian Optimization

In engineering system design, minimizing the variations of the quality measurements while guaranteeing their overall quality up to certain levels, namely the robust parameter design (RPD), is crucial. Recent works have dealt with the design of a system whose response-control variables relationship is a deterministic function with a complex shape and function evaluation is expensive. In this work, we propose a Bayesian optimization method for the RPD of stochastic functions. Dual stochastic response models are carefully designed for stochastic functions. The heterogeneous variance of the sample mean is addressed by the predictive mean of the log variance surrogate model in a two-step approach. We establish an acquisition function that favors exploration across the feasible and optimality-improvable regions to effectively and efficiently solve the stochastic constrained optimization problem. The performance of our proposed method is demonstrated by the extensive numerical and case studies. <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Note to Practitioners</i> —Many manufacturing processes involve undesirable variations, which create variations in the final products. For example, many emerging manufacturing processes, such as nanomanufacturing, involve complex physical and chemical dynamics and transformation, creating variations in the manufacturing output. In such processes, it is crucial to design the manufacturing processes or products so that they have minimum variations in their quality. Meanwhile, it is also important to maintain the overall quality of the designed processes or products. Furthermore, acquiring data from many advanced manufacturing processes is often very costly, especially in the designing stage. In this work, we propose a data-driven method that automatically finds the best setting of manufacturing processes or products with the minimum variations of quality and a given constraint on the average quality satisfied. Our proposed method is used before conducting every experiment; It analyzes the historical data from previous experiments and provides a setting to be used in the next experiment. Our proposed method efficiently utilizes the historical data, and thus finds the best robust setting by conducting only a small number of experiments.

Sobrepeso y obesidad materna antes del embarazo como predictores de asma infantil en menores de cinco años: una cohorte retrospectiva en Perú

Abstract Objectives: to estimate the role of maternal overweight and obesity before pregnancy as predictors of childhood asthma in a population of Peruvian children under five years. Methods: we carried out a retrospective cohort study of children aged five years or less and their mothers from the Regional Hospital of Ayacucho and the María Auxiliadora Hospital in Lima, Peru. We included children who were born between 2013 and 2014 and follow them up until 2018 and 2019, respectively. The diagnosis of overweight and obesity of the mother before pregnancy and asthma in the child were registered in their clinical histories. Crude (cRR) and adjusted relative risks (aRR) and 95% confidence intervals (CI95%) were obtained using a generalized lineal model of the Poisson family with link log and robust variances. Results: we evaluated 431 medical records and found that 20.9% of the children had asthma, 26.7% of the mothers were overweight, and 20.2% were obese before pregnancy. In the adjusted regression model, overweight (aRR=2.94; CI95%= 1.54-5.60) and maternal obesity (aRR=5.10; CI95%= 2.73-9.51) were predictors of an increased risk of childhood asthma. Conclusions: maternal overweight and maternal obesity increased the risk of her children developing asthma threeand five-fold, respectively.

Low-Density Lipoprotein Cholesterol Is Not a Major Determinant of High-Sensitivity C-Reactive Protein Levels in People Without Known Diabetes Mellitus.

Background: It has been well established that high-sensitivity C-reactive protein (hs-CRP) is strongly associated with obesity, insulin resistance, high blood pressure, and dyslipidemia. However, the effects of different lipid parameters on hs-CRP levels are less deliberated. The purpose of the study was to compare the relative contribution of triglycerides (TGs), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C) to the levels of hs-CRP. Methods: Three hundred seventy-eight subjects without known history of diabetes were recruited for the study. No concomitant antilipid or antidiabetes agents were allowed. Each subject received anthropometric measurements, fasting sampling for lipid profile and hs-CRP, and a 75-gram oral glucose tolerance test for the measurements of insulin resistance (surrogated by insulin sensitivity index ISI0,120). Results: Levels of hs-CRP levels were positively correlated with Log (TG) and negatively correlated with HDL-C in partial correlation after adjustments for confounding variables, but not with LDL-C. The hs-CRP levels in the three groups by tertiles of LDL-C were similar. Subsequently, we found that body mass index (first step), Log (ISI0,120) (second step), and Log (TG) (third step) independently predicted the variance of Log (hs-CRP) in stepwise multiple regression. However, both HDL-C and LDL-C failed to be entered into the models to explain Log (hs-CRP). Conclusions: Our data demonstrated that Log (TG) was a major lipid determinant of hs-CRP levels. The contribution of LDL-C to the levels of hs-CRP might be insignificant.

Spatial Integration of Cellular Shapes in Green Microalgae with Complex Morphology, the Genus Micrasterias (Desmidiales, Zygnematophyceae)

While ontogeny of multicellular organisms requires an interplay among tissues, morphogenesis of unicellular structures is typically organised with respect to differential growth of their cell covering. For example, shapes of various microalgae have often been emphasised as examples of symmetric fractal-like cellular morphology. Such a self-similar pattern is typical for the variability of a spatial fractal, with the shape variation remaining the same at different scales. This study investigated how these cells are integrated. A geometric morphometric analysis of spatial integration in the genus Micrasterias was used to assess the variation across scales by comparing the slopes of the linear fit of the log bending energy against the log variance of partial warps. Interestingly, the integration patterns were distinctly different from the notion of self-similarity. The variability consistently increased with decreasing scale, regardless of the cultivation temperature or the species examined. In addition, it was consistent after the adjustment of the slopes for the digitisation error. The developmental control over the final shape progressively declines with decreasing spatial scale, to the point that the terminal lobules are shaped almost independently of each other. These findings point to possible considerable differences in the generation of morphological complexity between free-living cells and multicellular organisms.

Review of calculation of conditional power, predictive power and probability of success in clinical trials with continuous, binary and time-to-event endpoints

Assessment of study success using conditional power (CP), the predictive power of success (PPoS) and probability of success (PoS) is becoming increasingly common for resource optimization and adaption of trials in clinical investigation. Determination of these measures is often a non-trivial mathematical task. Further, the terminologies used across the literature are not consistent, and there is no consolidated presentation on this. We have made a structured presentation on these measures for both trial success and clinical success: first, we have summarized the expressions of CP, PPoS and PoS in a general setting and subsequently, expressions for these measures are obtained for continuous, binary, and time-to-event endpoints in single-arm and two-arm trial settings. Many of these expressions are previously published; however, some of the expressions are very new including the expressions for testing median of time-to-event endpoint in a single-arm trial. We have also shown that $$1/(\text{ no. } \text{ of } \text{ events})$$ consistently underestimates the variance of log(median) and alternative expression for variance was derived. Examples are given along with the comparison of CP and PPoS. Expressions presented in this paper are implemented in LongCART package in R and in R shiny app https://ppos.shinyapps.io/public/ .

PAH atmospheric log(KP) values in Great Lakes samples are related to black carbon levels near each site

Many semi-volatile organic pollutants are present in the atmosphere both in the vapor and particle phases. About 50 years ago, a partition coefficient (KP) was defined as the compound's concentration in the particle phase (Cpart, in ng/m3 or pg/m3) divided by its concentration in the vapor phase (Cvapor, also in ng/m3 or pg/m3) divided by the atmospheric concentration of total suspended particles (TSP, in μg/m3) or, more recently, by the concentration of particulate matter with aerodynamic diameters less than 2.5 μm (PM2.5, also in μg/m3). The original point of this term was to account for surface adsorption of pollutants to the particles, but over the years it has become apparent that absorption, particularly to black carbon (BC, also known as elemental carbon) in the particles, may also be important. This study investigates the importance of this particle term using about 3000 polycyclic aromatic hydrocarbon (PAH) concentrations measured from 1997 to 2018 (inclusive) in 24-h samples collected once every 12 days at five sites on the shores of the North American Great Lakes and using U.S. Environmental Protection Agency PM2.5 concentrations at the same sites. Analyses of variance of the annual mean log(KP) values show significant differences for all six compounds among the five sites, which we attribute to the composition of the particles at the five sites. For example, the particles from the urban sites are likely to have higher black carbon levels compared to those from the more rural and remote sites. With an additional term for black carbon in these samples, these new ratios are similar across sites for a given compound. These results suggest that a black carbon term is useful and potentially important.

Association between blood glucose levels and autonomic symptoms in Peru

AimsTo determine whether there is an association between high blood glucose levels and having autonomic symptoms among adults aged 30–69 years. Material and methodsA population-based cross-sectional study was conducted. The presence of autonomic symptoms was defined as the positive response to any item of the Survey of Autonomic Symptoms (SAS). Blood glucose levels were defined as euglycemia, prediabetes, and type 2 diabetes (T2D), based on oral glucose tolerance test. Poisson regression, with link log and robust variance, and linear regression were conducted to evaluate the association of interest. ResultsA total of 1607 subjects, mean age 48.2 (SD: 10.6) and 810 (49.7 %) women, were included. T2D was associated with higher prevalence of erectile dysfunction (PR = 3.00; 95 % CI: 1.78–5.02) and dryness of mouth and eyes (PR = 1.29; 95 % CI: 1.02–1.61) compared with those with euglycemia. Those with T2D had 0.32 (95 % CI: 0.04–0.62) and 1.03 (95 % CI: 0.03–2.03) more points in the SAS score and severity scale, respectively. ConclusionsErectile dysfunction and dry mouth and eyes are the more common autonomic symptoms associated with T2D. Our results suggest a periodic evaluation of sexual function and eye humidity among T2D patients.

The impact of the COVID-19 pandemic on gender-based violence and physical violence among women in Peru

Background: Gender-based violence (GBV) is an increasing social problem worldwide, but it has been neglected despite its high relevance to women’s health. In this study, we aim to assess the coronavirus disease 2019 (COVID-19) pandemic impact on GBV incidence in Peruvian, determine the physical violence prevalence and its associated factors among GBV victims. Methods: We assessed the impact of the COVID-19 pandemic on the GBV weekly incidence by fitting an autoregressive integrated moving average model. Additionally, we assessed the physical violence prevalence and its associated factors by fitting a multivariate Poisson regression model with a link log and robust variance. Results: We analyzed 588,587 cases of women victims of GBV and calculated an annual GBV incidence of 518, 714, 958, 596, and 846 cases per 100,000 women during the years 2017-2021, respectively. During the COVID-19 pandemic, the observed GBV weekly incidence went significantly below the forecasted GBV weekly incidence since 2021. Overall, most GBV cases were of middle to high-risk (76%), regular (75%), and verbal (82%) violence. Most victims were single (81%), rural (75%), mothers with children (60%), who did not complete high school (54%). Most aggressors were men (81%), paid workers (77%), had completed high school education (63%), and partner of their victims (58%). Around 44% of the victims suffered physical violence and its main associated factors were aggressor’s school education (adjusted prevalence ratio = 0.89; 95% confidence interval: 0.88-0.89), aggressor’s age &lt;40 years old (1.30; 1.29-1.30), aggressor’s paid job (0.99; 0.98-0.99), prior violence report (1.27; 1.26-1.27), victim’s age &lt;40 years old (1.23; 1.22-1.24), and victim non-Peruvian citizenship (1.04; 1.01-1.07). Conclusions: GBV is endemic in Peru, but the COVID-19 pandemic reduced its burden significantly in 2020-2021. Several characteristics of the cases, victims, and aggressors have changed over time, offering new opportunities for implementing interventions to address this social problem.

Reference curve sampling variability in one-sample log-rank tests.

The one-sample log-rank test is the method of choice for single-arm Phase II trials with time-to-event endpoint. It allows to compare the survival of patients to a reference survival curve that typically represents the expected survival under standard of care. The one-sample log-rank test, however, assumes that the reference survival curve is known. This ignores that the reference curve is commonly estimated from historic data and thus prone to sampling error. Ignoring sampling variability of the reference curve results in type I error rate inflation. We study this inflation in type I error rate analytically and by simulation. Moreover we derive the actual distribution of the one-sample log-rank test statistic, when the sampling variability of the reference curve is taken into account. In particular, we provide a consistent estimate of the factor by which the true variance of the one-sample log-rank statistic is underestimated when reference curve sampling variability is ignored. Our results are further substantiated by a case study using a real world data example in which we demonstrate how to estimate the error rate inflation in the planning stage of a trial.

MO540: Are the Haematological Markers of Inflammation Predictors of Fibroblast Growth Factor-23 in Non-Dialysis Chronic Kidney Disease?

Abstract BACKGROUND AND AIMS Recently, a growing body of evidence point to the relationships between inflammation and fibroblast growth factor 23 (FGF23) in adults with and without chronic kidney disease (CKD). On the other hand, some haematological indices derived from the complete blood count appear as simple and inexpensive biomarkers of systemic inflammation. Therefore, this study aimed to evaluate the association between the haematological markers of inflammation and FGF23 in non-dialysis CKD. METHOD This single centre, cross-sectional study prospectively enrolled 90 subjects with moderate to severe stable CKD [median estimated glomerular filtration rate (eGFR) 25 (95% confidence interval 95% CI 24.9–30.5) mL/min, 46% in stage G3, urinary albumin-to-creatinine ratio (ACR) 221 (95% CI 498–954) mg/g], mostly males (61%), aged 62 (95% CI 57–64) years. Patients on renal replacement therapy (RRT) and those with active malignancies, infectious and inflammatory diseases were excluded. Demographic, past medical history (CKD vintage and etiology, comorbidities, chronic medications) and laboratory data were collected. Haematological markers of systemic inflammation [red blood cell distribution width (RDW), platelet distribution width (PDW), neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR)] were obtained from the complete blood count. Other measured lab parameters were: c-terminal FGF23 (cFGF23), intact parathyroid hormone (iPTH), serum calcidiol (25OHD), total calcium (tCa), phosphate (PO4), alkaline phosphatase, C-reactive protein, albumin, transferrin, ferritin and transferrin saturation, as markers of mineral metabolism, inflammatory, nutritional and iron status, respectively. Associations among studied parameters were assessed by Spearman rank test, multivariate linear regression and logistic regression models. Non-parametric variables were log-transformed. RESULTS The median cFGF23 was 4.65 (95% CI 7.57–14.4) pg/mL. Subjects in the highest cFGF23 quartile [n = 22, cFGF23 20.8 (95% CI 20.8–40.8) pg/mL] had higher RDW (P = 0.02), iPTH (P &amp;lt; 0.001), PO4 (P = 0.005) and ACR (P = 0.004), but lower tCa (P = 0.04), haemoglobin (P = 0.01) and eGFR (P &amp;lt; 0.001) as compared to those in the lowest quartile [n = 23, cFGF23 0.84 (95% CI 0.71–1.10) pg/mL]. Moreover, they had higher proportions of arterial hypertension (P = 0.01) and previous treatment with intravenous iron (P = 0.03). A trend to higher PLR (P = 0.052), NLR (P = 0.064), and ferritin (P = 0.076) was also observed. However, beside the expected bivariate correlations with eGFR, ACR, iPTH, tCa and PO4, cFGF23 was further correlated solely with haemoglobin (rs = –0.33, P = 0.002). In a multivariate linear regression model which explained 34% of the log(cFGF23) variance, log(PLR) (B 1.59, 95% CI 0.14–3.03, P = 0.03) and log(eGFR) (B –1.65, 95% CI –2.51 to –0.80, P &amp;lt; 0.001) were independent predictors. After adjustment for history of arterial hypertension and previous intravenous iron treatment, in a model of logistic regression (Nagelkerke R2 0.57, Chi2 16.7, P = 0.03), log(eGFR) was found as independent predictor of the log(FGF23) [odds ratio (OR) 0.07, 95% CI 0.01–0.36, P = 0.002]. However, RDW was retained in the last step of this model with a borderline significance (OR 4.3, 95% CI 0.98–19.02, P = 0.052). CONCLUSION Taken together, our findings suggest that, in addition to the kidney function, RDW and PLR seem to predict cFGF23 in non-inflammed, stable, non-dialysis CKD adults. Thus, one might speculate in favour of the association between chronic inflammatory state and FGF23 metabolism and in support of the revelatory role of some haematological markers of inflammation, a hypothesis that needs further research.

Experimental Designs to Study the Aggregation and Colonization of Biofilms by Video Microscopy With Statistical Confidence.

The goal of this study was to quantify the variability of confocal laser scanning microscopy (CLSM) time-lapse images of early colonizing biofilms to aid in the design of future imaging experiments. To accomplish this a large imaging dataset consisting of 16 independent CLSM microscopy experiments was leveraged. These experiments were designed to study interactions between human neutrophils and single cells or aggregates of Staphylococcus aureus (S. aureus) during the initial stages of biofilm formation. Results suggest that in untreated control experiments, variability differed substantially between growth phases (i.e., lag or exponential). When studying the effect of an antimicrobial treatment (in this case, neutrophil challenge), regardless of the inoculation level or of growth phase, variability changed as a frown-shaped function of treatment efficacy (i.e., the reduction in biofilm surface coverage). These findings were used to predict the best experimental designs for future imaging studies of early biofilms by considering differing (i) numbers of independent experiments; (ii) numbers of fields of view (FOV) per experiment; and (iii) frame capture rates per hour. A spreadsheet capable of assessing any user-specified design is included that requires the expected mean log reduction and variance components from user-generated experimental results. The methodology outlined in this study can assist researchers in designing their CLSM studies of antimicrobial treatments with a high level of statistical confidence.

Abstract 13147: The Internally Translated Isoform of Connexin 43, GJA1-20k Rescues Cx43 Trafficking and Reduces Arrhythmias in the DSG2 Mutant Model of Arrhythmogenic Cardiomyopathy

Introduction: Arrhythmogenic cardiomyopathy (ACM) is an inherited condition caused by mutations of junctional proteins resulting in heart rhythm abnormalities, heart failure and sudden cardiac death. ACM subjects exhibit a loss of normal trafficking of the gap junction protein Connexin 43 (Cx43) to the intercalated disk. Our group has previously demonstrated that the Cx43 gene, GJA1, undergoes internal translation to form multiple truncations of the full-length protein. The 20 kilodalton isoform, (GJA1-20k) is required for trafficking of Cx43 gap junction channels, and exogenous expression of GJA1-20k increases trafficking of full length Cx43 to the membranes and the intercalated disk. Here, we hypothesize that GJA1-20K will reduce dysrhythmias by improving trafficking of Cx43 to the intercalated disc in a mouse model of ACM. Methods: Desmoglein 2 (DSG2) homozygous knock-out mice, producing a typical ACM phenotype, were injected with a viral vector containing either GJA1-20K-GFP or GFP alone at four weeks of age along with wild-type littermate controls. Echocardiography was performed every four weeks and Telemetry was recorded at ~18-19 weeks of age to record cardiac electrical activity over a continuous 12 hour period. At 20 weeks, the mice were sacrificed, and hearts were harvested for further analysis. Results: Compared to WT littermates DSG2-KO mice that received a GFP viral vector demonstrated over a 100 fold increase in mean number of PVCs observed over a 12 hour period (2 vs 371 respectively p=0.0005). Mice that received the GJA1-20k viral vector in contrast demonstrated significantly fewer PVCs than their GFP treated littermates 43 vs 371. (analysis of variance of Log(#PVC) p =0.015 N = 6-7 mice/group). Quantitative immunofluorescence analysis of hearts confirmed an increase in Cx43 localization at the intercalated disk (as measured as a percent of N-Cadherin-Cx43 colabeling) in mice treated with GJA1-20k relative to GFP (25% vs 6% respectively N= 7 images/mouse and 3 mice/ group) t-test p=0.0009). Conclusions: Our data indicate that GJA1-20K significantly reduces the number of PVCs and recovers Cx43 trafficking to the intercalated disk in a mouse model of ACM. Our results point to a therapeutic option for the treatment of ACM related arrhythmias.

Prevalence and predictors of work-related musculoskeletal disorders among workers of a gold mine in south Kivu, Democratic Republic of Congo

BackgroundWork-related musculoskeletal disorders (WRMSDs) are a major constraint to worker performance and health. However, research on their prevalence and associated factors among workers at gold mines in the Democratic Republic of Congo (DRC) is insufficient. The present study aimed to determine the prevalence and predictors of WRMSDs among workers of a Gold Mine in South Kivu, DRC.MethodsCross sectional data on prevalence of WRMSDs and risk factors was collected using a modified Nordic questionnaire and upper limb Core QX checklist from 196 workers of a gold mine. WRMSDs were defined as pain or injury(ies) or discomfort, numbness or limitation of movement in the musculoskeletal system at any time in the past 12 months which lasted at least 24 h. These had to be either induced or aggravated by work and circumstances of its performance. A generalised linear model of the Poison family with link log and robust error variances was used to generate prevalence ratios (PRs) and 95% confidence intervals (CIs) for the factors associated with WRMSDs. The effect of individual, ergonomic and psychosocial factors on WRMSDs were investigated while controlling for known confounders.ResultsMost workers were males 187 (95.4%) and their age ranged between 23 and 60 years with mean of 36.3 years. Of the 196 workers, 49 (25.0%) reported having at least one WRMSD during the previous 12 months. WRMSDs with highest occurrence rate were the lower back pain (14.8%), followed by thighs/hip pain (9.2%) and shoulder pain (8.2%). Prolonged heavy lifting/shovelling shovelling (PR = 1.69, 95% CI [1.32, 3.24] and longer work shifts (> 9 h) (PR = 3.56, 95% CI [1.76, 16.58]) were predictive for WRMSDs while jobs with low demands were protective against WRMSDs (PR = 0.18, 95% CI [0.08, 0.44]).ConclusionThe prevalence of WRMSDs is high and associated with prolonged heavy lifting/shovelling, longer work shifts and job demands. We recommend lowering workload and job demands and improving work ergonomics to mitigate and prevent the WRMSDs among workers in goldmines.

Automatic lung sound cycle extraction from single and multichannel acoustic recordings

A lung sound signal (LSS) consists of a series of inhalations–exhalations or lung sound cycles (LSCs), which provide valuable information about the status of the lungs. Currently, semiautomatic techniques are used to extract LSCs from an LSS. These face limitations in terms of extra cost and effort due to the need of reference signal and inconvenience caused to the patients. Automatic LSC extraction from lung sound (LS) recording can overcome these limitations. In this work, a novel signal processing based method is proposed for extraction of LSCs automatically. At first, the log variance features are calculated from preprocessed LSS, which represent an approximation of the respiratory flow and envelope, but it exhibits spikes. A novel filter-based approach is implemented to smoothen the envelope for better representation of the LSCs’ onset and offset points. The filtered envelopes representing the LS flow are selected through a majority voting technique employing single and multichannel frameworks. The study is conducted on 32 normal and 90 diseased subjects. The mean accuracy (ACC) and onset–offset error (τ) observed for normal category are 94.61% and 0.22 s for both multichannel and single channel frameworks. The same for diseased categories are within 88.96–94.18% and 0.31–0.34 s in multichannel framework and 86.75–92.73% and 0.28–0.34 s in single channel framework. These results are found to be superior when compared with a recently proposed method. The work addresses an important step towards non-invasive computer-aided LS analysis by automated segmentation of LSS without using any additional sensor.

Variations in patterns of internode and branch lengths for several bamboo species

Bamboos are an important plant resource both economically and ecologically and it is, therefore, important to fully understand their biosystem characteristics. In this study, the variations in patterns of internode and branch lengths for twelve bamboo species were examined. The results indicated that node distribution along the culm is not always dense near the ends of the culm and sparse in the middle part of the culm. There were variations in the position of maximum internode length among the 12 bamboo species. For most bamboo species, maximum internode lengths correlated with total culm heights. Similar relationships existed between log (node number) and log (accumulated internode length) at the individual and species levels, and these relationships can be fitted by a linear or sigmoid function of the third-order function. Scaling exponents changed gradually during internode growth for individuals. The relationships between log (average of internode length) and log (variance of internode length) were complicated between individuals and species. The frequency distribution of bamboo branches followed power laws, but the exponents varied with species and individuals. The results may provide a new understanding of the optimal design in the unique biosystem of bamboos.

ALTERED EXPRESSION OF GENES INVOLVED IN JAK-STAT, ADIPOCYTOKINE AND TOLL-LIKE RECEPTOR SIGNALING PATHWAYS ARE DETECTED IN BLASTOCOEL FLUID CONDITIONED MEDIA FROM EUPLOID EMBRYOS WITH POSITIVE IMPLANTATION OUTCOMES

Altered gene expression leading to modified expressions of pathways in preimplantation embryos may be a contributing factor in successful embryo implantation outcome. Identification of genes in day-5 blastocysts that are associated with successful uterine implantations would provide reproductive specialists with an additional measure of embryo quality when selecting the most viable embryo for transfer. This study evaluated global gene expression using RNASeq in blastocoel fluid-conditioned media from euploid IVF-generated embryos resulting in successful implantations versus those that failed to successfully implant. Retrospective analysis of day-5 euploid blastocoel fluid gene expression in seven (three successful; four unsuccessful) euploid embryos. Blastocoel fluid-conditioned media was obtained following biopsy of ICSI-generated day-5 blastocysts. RNA extractions, library preparation (SMART-Seq Stranded kit) and Illumina NextSeq500 sequencing were performed at the USC Functional Genomics Core. Standard RNASeq workflow was conducted: 1) removal of adaptor sequences 2) alignment to human Gh38 genome with STAR, and 3) FeatureCount to obtain raw gene count number for each sample. Differential gene expression analysis (DGE) of raw counts was performed using DESeq2 applying negative binomial generalized linear models and taking advantage of the package to generate more accurate shrunken log fold changes and variance stabilizing estimators for data with considerations regarding low counts and high dispersion. Significance was defined as a false-discovery rate (FDR) p-value <0.05 to adjust for multiple testing. Pathway analysis was performed using GAGE, mapping genes to KEGG pathways. After quality control 21,321 genes were included in the DGE analysis and 36 (FDRp<0.05) were identified as DE (6 up-regulated / 30 down-regulated). Pathway analysis revealed altered expression patterns of genes encoding proteins in the adipocytokine, Toll-like receptor and JAK-STAT signaling pathways between blastocoel fluid from embryos associated with successful versus unsuccessful implantation outcomes. Specifically, gene products of these pathways were up-regulated in blastocoel fluid from embryos associated with successful implantation. We identified differential gene expression in blastocoel fluid from euploid embryos associated with successful versus unsuccessful implantation. JAK-STAT pathway members were identified in this study, which is supported by a previous reports that members of this pathway are expressed during blastocyst stage development. Detection of these gene products in blastocoel fluid may represent apoptotic remnants of cells that were selectively eliminated from the developing embryo. One possibility is that the JAK-STAT pathway activates apoptotic gene expression in specific cells within the embryo as a means of embryo self-correction. Future research aims to clarify the roles of identified genes and consider bi-directionally dysregulated genes within a given pathway in the preimplantation embryo.

A-095 Processing Speed Indicators in Juvenile Huntington’s Disease: Assessing CAG Repeat, Age of Onset, and Mood

Abstract Objective In adult onset Huntington’s Disease (HD), processing speed deficits and depression can be detected in the prodromal stages. These factors, along with CAG repeat length, may be predictive of age of symptom onset. However, less is known about the relationship between the aforementioned factors for patients diagnosed with Juvenile Huntington’s Disease (JHD). The current study aimed to investigate the relationships between age of symptom onset, CAG repeat, processing speed, and mood to improve prediction of symptom manifestation for JHD patients. Method Data was analyzed from the Kids HD study and included 30 participants (age at diagnosis M = 13.6, SD = 5.4, CAG repeat mean = 69, SD = 16). Bivariate partial correlations, independent t-tests, and regression analyses examined differences in processing speed across CAG repeat, age of onset, and depressive symptomology. Results CAG repeat length significantly predicted the natural log of age at diagnosis, β = −.59, t(25) = −3.59, p &amp;lt; .01, and significantly explained variance in the natural log of age at diagnosis, R2 = .35, F(1, 25) = 12.86, p &amp;lt; .01. Finally, results indicated that CAG repeat length also predicted processing speed abilities when controlling for depressed mood symptomology, R2 = .39, F(3,24) = 5.18, p &amp;lt; .01. Conclusion CAG repeat length holds predictive power for the age of diagnosis and for processing speed, even when accounting for covariate depressive mood indicators. Overall, results indicate evidence of impacted processing speed abilities given expansive CAG repeat numbers. This is consistent with a subcortical neurodegenerative process, such as HD.