GLM Model Research Articles

Determinants of impaired coupling of right ventricle to hemodynamic load in advanced HFrEF

Abstract Background The mechanisms and consequnces of impaired right ventricular (RV) dysfunction and impaired RV-pulmonary artery (PA) coupling in advanced heart failure (HF) poorely understood. Purpose To compare RV-PA coupling parameters in patients with advanced HFrEF, PAH and in controls to ellucidate determinants and prognostic impact of RV-PA uncoupling in HFrEF. Methods 260 pacients with advanced HF (NYHA 3.0±0.5, 40% CAD, LVEF: 23±10%, 87% males, BMI: 28±4.5 kg/m2, BNP: 1238±982 pg/ml), 39 controls and 21 PAH patients underwent lab tests, ecocardiography, right heart catheterisation and equilibrium gated blood pool SPECT to precisely measure cardiac volumes. RV End-systolic elastance (Ees) and Effective arterial elastance (Ea) were calculated by single beat method. Patients were longitudinally followed for occurrence of adverse outcome (urgent Tx, LVAD or death without Tx/LVAD). Results PAH patients had higher PA pressures and more dilated RV than HFrEF and controls. Despite of that, RV-PA coupling, reflected by Ees/Ea ratio, was more profoundly reduced in HFrEF than in PAH (Figure). While RV contractility (Ees) was augmented by increased afterload in PAH, such augmentation was absent in HFrEF. At follow-up (median 258; 53–763 days), 69% of HFrEF subjects experienced adverse event (17% death, 24% urgent HTx, 28% LVAD). In HFrEF, RV-PA coupling was strongly predictive od adverse outcome, more than RV EF%, RV EDV or RV Ees. The strongest predictors of reduced RV Ees/Ea ratio in HFrEF were in descending order: RV EF, RV EDV, PA systolic/systemic systolic pressure ratio (PAs/SBP), PAWP, heart rate, PA compliance, RA mean pressure, PA mean pressure, BNP level, SBP, PAs, Tri Reg grade, Non-CAD etiology of HF, Mi Reg grade, PVR, RV dyssynchrony, absence of ACEi/ARB/S-V (GLM model, all p<0.001). RV Ees/Ea ratio correlated with PAs/SBP ratio, that reflects systolic ventricular interdependence. Invasive PAs/SBP predicted outcome and closely correlated with non-invasive estimation of PAs/SBP. Conclusion Despite having less PH and smaller RV, RV coupling is more impaired in HFrEF than in PAH due to absence of RV contractility enhancement. Higher RV volume, heart rate, tricuspid regurgitation, lower PA compliance, higher PAWP and systolic ventricular interdependence (PAs/SBP) are main determinants of RV PA decoupling in HFrEF. Elevated PA systolic pressure but low systemic BP (high PAs/SBP ratio) is associated with poor RV-PA coupling and prognosis. Funding Acknowledgement Type of funding sources: Public grant(s) – National budget only. Main funding source(s): AZV NU20-02-00052, AZV NU21-02-00402

Evaluation of lung inflammation from daily exposures to fine and ultrafine particulate matter in a trade school

Background - Daily short-term exposure to ambient fine particles (PM₂.₅ ; < 2.5 μm) in the general environment has been related to acute respiratory effects such as respiratory symptoms and inflammation, emergency room visits for respiratory conditions and mortality. Although exposure is higher in trade/occupational settings, acute respiratory effects of daily exposures remain unexplored. Objective - To evaluate the association between daily exposures to fine particles (PM₂.₅) and Ultrafine Particles (UFP; < 0.1 μm), and fractional exhaled nitric oxide (FeNO), a relevant indicator of lung inflammation, in two trade settings from a construction school. Method - A repeated-measure panel study was carried out on students performing welding and bricklaying activities (n=30). PM₂.₅ and UFP concentrations were measured daily (area measurements with direct-reading instruments) and fractional exhaled FeNO were measured two times per day, pre-work and post-work, for 5 consecutive days. Mixed GLM models were used to assess associations. Results - Daily geometric mean exposure to PM₂.₅ from welding and bricklaying activities were respectively 183 μg/m³ (σg=3.5) and 90.8 μg/m³ (σg=1.6). Daily geometric mean UFP concentrations for these activities were 106,000 (σg=1.6) particles/cm³ and 4,400 (σg=1.7) particles/cm³. Combining bricklaying and welding activities, for a 10,000 particles/cm³ increase in UFP, there was a 0.2 ppb (95%CI: 0.05-0.3) increase in FeNO inter-day. There was also a tendency for a small increase in FeNO (0.2 ppb; 95%CI: -0.06 - 0.5) per 100 µg/m³ of PM₂.₅ . Further analyses will be performed with additional participants and stratified by occupational trade. Conclusion - Bricklaying and welding activities expose workers daily to PM₂.₅ and UFP that may contribute to recurrent pulmonary inflammation and impair respiratory health. Keywords: particulate matter, occupational exposures, short-term exposure, pulmonary inflammation.

A Variation in the Mortality of European Anchovy and European Pilchard After Sieving and Discarding from a Purse Seine Fishery in the Eastern Mediterranean

Discard mortality of European anchovy (Engraulis encrasicolus) and European pilchard (Sardina pilchardus) was investigated during commercial purse seine fishing operations off İzmir Bay, Turkey. In total, 6703 anchovy and 2545 sardine individuals were observed for seven days in five survival experiments carried out from March to October 2019. Only in March, fish cages were used and observed by divers. In the other trials, fish were observed in holding tanks; dead fish were collected and any surviving fish were fed. In the study, we compared the mortality of sorted and unsorted fish. The GLM model for European anchovy demonstrated a highly significant category effect (p<0.0001) and a highly significant interaction between length-related mortality and season (CL: season; p<0.0001). There were also significant differences in length-related mortality ratio according to the different categories in both seasons (p<0.0001). However, there was a highly significant interaction between mortality ratio, length, uncrowded category, and spring (p<0.005) for European pilchard. The observations showed that high mortalities occurred in the sorted fish categories of both pelagic species during the experiments.

Mixed exposure to phenol, parabens, pesticides, and phthalates and insulin resistance in NHANES: A mixture approach

PurposeThe effects of environmental chemicals on insulin resistance have attracted extensive attention. Previous studies typically focused on the single chemical effects. This study adopted three different models to analyze the mixed effects of nine common chemicals (one phenol, two parabens, two chlorophenols and four phthalates) on insulin resistance. MethodsUrinary concentrations of chemicals were extracted from National Health and Nutrition Examination Survey (NHANES) 2009–2016. Insulin resistance was assessed using homeostatic model assessment (HOMA) and defined as HOMA-IR >2.6. The generalized linear regression (GLM), weighted quantile sum regression (WQS) and Bayesian kernel machine regression models (BKMR) were applied to assess the relationship between chemical mixture and HOMA-IR or insulin resistance. ResultsOf the 2067 participants included, 872 (42.19 %) were identified as insulin resistant. In single-chemical GLM model, di-2-ethylhexyl phthalate (DEHP) had the highest parameter (β/OR, 95 % CIs) of 0.21 (quartile 4, 0.12– 0.29) and 1.95 (quartile 4, 1.39– 2.74). Similar results were observed in the multi-chemical models, with DEHP (quartile 4) showing the positive relationship with HOMA-IR (0.18, 0.08– 0.28) and insulin resistance (1.76, 1.17– 2.64). According to WQS models, the WQS indices were significantly positively correlated with both HOMA-IR (β: 0.07, 95 % CI: 0.03– 0.12) and insulin resistance (OR: 1.25, 95 % CI: 1.03– 1.53). DEHP was the top-weighted chemical positively correlated with both HOMA-IR and insulin resistance. In the BKMR model, the joint effect was also positively correlated with both outcomes. DEHP remained the main contributor to the joint effect, consistent with WQS analysis. ConclusionOur findings suggested that these chemical mixtures had the positive joint effects on both HOMA-IR and insulin resistance, with DEHP being the potentially predominant driver. The inter-validation of the three models may indicate that reducing the DEHP concentration could improve glucose homeostasis and reduce the risk of insulin resistance. However, further studies are recommended to deepen our findings and elucidate the mechanisms of insulin resistance and chemical mixture.

Association mapping for abiotic stress tolerance using heat- and drought-related syntenic markers in okra.

Considerable production losses are caused by heat and drought stress in okra. Germplasm evaluation at genetic level is essential for the selection of promising genotypes. Lack of genomic information of okra limits the use of genetic markers. However, syntenic markers of some related family could be used for molecular characterization of major economic traits. Herein, 56 okra genotypes were evaluated for drought and heat tolerance. Sixty-one expressed sequence tags (ESTs) identified for heat and drought tolerance in cotton were searched from literature surveys and databases. The identified ESTs were BLAST searched into okra unigene database. Primers of selected okra unigenes were synthesized and amplified in all genotypes using standard polymerase chain reaction (PCR) protocol. Marker trait association (MTA) of the syntenic unigenes were identified between genotypic and phenotypic data on the basis of linkage disequilibrium Functional syntenic analysis revealed that out of these 61 cotton ESTs 55 had functional homology with okra unigenes. These 55 unigenes were used as markers for further analysis (amplification). Okra genotypes showed significance variations for all the physo-morphological parameters under heat and drought stress. Genotypes Perbhani Karanti, IQRA-III, Selection Super Green, Anmol and Line Bourd performed better under drought stress whereas genotypes Perbhani Karanti, IQRA-III, Green Gold, OK-1501 and Selection Super Green showed heat tolerance. Fifty markers showed amplification in okra. Fifty-six okra genotypes were clustered into three distinct populations. LD analysis has shown most significant linkage between markers Unigene43786 and Unigene3662. MTAs using MLM and GLM models revealed that 23 markers have significant associations (p < 0.05) with different traits under control and stressed conditions. Relative water content is associated with four markers (Unigene10673, Unigene99547, Unigene152901, and Unigene129684) under drought conditions. Whereas, Electrolyte leakage was associated with 3 markers (Unigene109922, Unigene28667 and Unigene146907) under heat stress. These identified unigenes may be helpful in the development of drought and heat tolerant genotypes in okra.

Rotifer Species Richness in Kenyan Waterbodies: Contributions of Environmental Characteristics

The aquatic microfauna of Africa is poorly characterized, especially in the case of planktonic rotifers inhabiting waterbodies other than large lakes. In addition, little is known about factors that structure these communities. Here, we assessed the roles of climatic region, habitat type, macrophyte abundance, and a suite of abiotic environmental factors in determining rotifer species’ richness and composition in waterbodies located across a 2300 m altitudinal gradient in Kenya. Plankton samples were obtained from 33 sites in 23 waterbodies. From these, 93 rotifer taxa were identified from 18 families comprising 31 genera. About one fourth (25 taxa) were new records for Kenya, from which 4 species were new for Africa. Species richness was the highest in permanent as compared to temporary habitats. Richness was strongly positively correlated with all environmental factors and strongly influenced by macrophyte abundance. When spatial structure was added to the GLM model, species richness was no longer significantly correlated with macrophytes. Unconstrained detrended correspondence analysis conducted at the species level indicated four suites of species associated with either (1) longitude, (2) elevation, (3) latitude, temperature, and hydroperiod, or (4) macrophytes. This study contributes to our knowledge of the patterns of rotifer biogeography and species richness in Africa.

Reszinate—A Phase 1/2 Randomized Clinical Trial of Zinc and Resveratrol Utilizing Home Patient-Obtained Nasal and Saliva Viral Sampling

Background: Safe, effective, and inexpensive treatment for COVID-19 is an urgent unmet medical need. Zinc and resveratrol have been reported to have antiviral activity, and resveratrol may increase zinc activity at the site of replication by increasing intracellular zinc concentrations.Methods: A 1:1 randomized, placebo-controlled trial of zinc 150 mg plus resveratrol 4 g daily for 5 days versus placebos in outpatients with SARS-CoV-2 was carried out from 9/21/2020–1/22/2021 in Seattle, Washington. Viral shedding was followed with patient self-collected nasal and saliva samples by measuring qRT-PCR for SARS-CoV-2 N gene days 1–7, 10, and 14. Patients filled out a web-based questionnaire on days 1–14 to report symptoms, vital signs and adherence to the study intervention. The study was posted as Clinical Trials.gov NCT04542993 on 9 September 2020.Results: A total of 30 participants (14 treatment; 16 placebos) had ≥1 day of the protocol treatment and were evaluable for the primary or secondary outcome. There was no difference in viral shedding between groups, nor in the resolution of symptoms. There was a trend toward a more rapid decrease in symptoms in the treatment group, though this was not statistically significant in the GLM model. Viral shedding was similar between patient self-collected mid-turbinate nasal swabs and expectorated saliva samples with a good correlation.Conclusion: SARS-CoV-2 shedding and COVID-19 symptoms were not statistically significantly decreased by treatment. Viral shedding correlates well between patient-obtained home nasal swabs and saliva sampling.

Traffic Safety at German Roundabouts—A Replication Study

Roundabouts are well-known for their ability to improve upon traffic safety, especially for motorized traffic. An in-depth analysis on this topic is known from previous work. It was found that different types of roundabouts have different levels of safety. The work at hand is a replication study for a previous study in this regard. It uses a mix of traditional and a Machine Learning (ML)-based approach, expands on the previous results and replicates some of the previous findings. This was possible especially by using a factor of 10 more roundabouts in the analysis, with considerably less manual intervention. Furthermore, this study could also draw some additional conclusions regarding the safety of bicyclists, which were not included in the original study. Finally, by using cross-validation techniques, a kind of minimal model could be established that needs fewer factors and achieves better prediction quality than straightforward glm models.

Mapping the FACT-G to EQ-5D-3L utility index in cancer with the Chinese values set

ABSTRACT Objective The purpose of this research was to create a function for mapping the cancer-specific instrument (FACT-G) to a preference-based measure (EQ-5D-3 L) utility index for health-related quality of life, with utility scores generated using the Chinese value set. Method A cross-sectional study among 243 Chinese patients with cancer was conducted through EQ-5D-3 L and FACT-G questionnaires survey. The EQ-5D-3 L utility index values were predicted based on OLS, GLM, CLAD, and Tobit model regression approaches. The performance and predictive power of each model were also evaluated using r 2 and adj- r 2, MAE, RMSE, ICC, and MID. Linear equating was used to avoid regression of the OLS model to mean. The model was validated using a 10-fold cross-validation method. Results Among all regression models for the FACT-G, the OLS 5 model predicted mean EQ-5D-3 L values the best, in terms of model goodness of fit (r 2 = 0.6230, MAE = 0.0448, RMSE = 0.0624). The OLS model proved to be the most accurate for the mean, and the linear equating scores were much closer to the observed scores. Conclusion Our results suggest that the best algorithm for FACT-G mapping to EQ-5D-3 L utility index is OLS model, based on the survey of Chinese patients with cancer.

Genome-wide association mapping and genomic prediction for pre‑harvest sprouting resistance, low α-amylase and seed color in Iranian bread wheat

BackgroundPre-harvest sprouting (PHS) refers to a phenomenon, in which the physiologically mature seeds are germinated on the spike before or during the harvesting practice owing to high humidity or prolonged period of rainfall. Pre-harvest sprouting (PHS) remarkably decreases seed quality and yield in wheat; hence it is imperative to uncover genomic regions responsible for PHS tolerance to be used in wheat breeding. A genome-wide association study (GWAS) was carried out using 298 bread wheat landraces and varieties from Iran to dissect the genomic regions of PHS tolerance in a well-irrigated environment. Three different approaches (RRBLUP, GBLUP and BRR) were followed to estimate prediction accuracies in wheat genomic selection.Results Genomes B, A, and D harbored the largest number of significant marker pairs (MPs) in both landraces (427,017, 328,006, 92,702 MPs) and varieties (370,359, 266,708, 63,924 MPs), respectively. However, the LD levels were found the opposite, i.e., genomes D, A, and B have the highest LD, respectively. Association mapping by using GLM and MLM models resulted in 572 and 598 marker-trait associations (MTAs) for imputed SNPs (− log10 P > 3), respectively. Gene ontology exhibited that the pleitropic MPs located on 1A control seed color, α-Amy activity, and PHS. RRBLUP model indicated genetic effects better than GBLUP and BRR, offering a favorable tool for wheat genomic selection.ConclusionsGene ontology exhibited that the pleitropic MPs located on 1A can control seed color, α-Amy activity, and PHS. The verified markers in the current work can provide an opportunity to clone the underlying QTLs/genes, fine mapping, and genome-assisted selection.Our observations uncovered key MTAs related to seed color, α-Amy activity, and PHS that can be exploited in the genome-mediated development of novel varieties in wheat.

410-P: Preoperative Diabetes Optimization and Clinical Outcomes

A diabetes optimization pathway for elective surgical patients with uncontrolled diabetes (A1c&amp;gt; 8%) has been in place at our institution for the last 5 years. Although we reported on improvement in glucose control before surgery in patients undergoing the intervention, impact on longer-term clinical outcomes was not known. We extracted EPIC medical record data for adult surgical patients in the diabetes optimization program between January 2016 and October 2021 (n=85) . The control group had uncontrolled diabetes and underwent surgery but had no intervention (n=1,111) . Logistic regression, GLM and Cox proportional hazard models were used to investigate relationship with 30 day complications, glucose at surgery, and overall mortality. Table 1 shows bivariate comparisons for the study cohort. The rates of perioperative complications were numerically lower in the intervention group, however, were not statistically significant. Unadjusted regression analyses found significantly lower glucose at surgery (β =-14.19, 95% CI=-27.94,-0.43) , and significantly lower hazard ratio for overall mortality (HR=0.34, 95% CI=0.13,0.93) for the intervention. After adjusting for demographics, clinical risk, and comorbidities, only glucose at surgery maintained significance (β =-16.89, 95% CI=-30.83,-2.95) . Prospective studies or a larger sample may be needed to confirm findings. Disclosure C.E.Mendez: Advisory Panel; Monarch Medical Technologies . R.J.Walker: None. E.Garacci: None. K.Pfeifer: None.

Time after time: detecting annual patterns in stream bacterial biofilm communities.

SummaryTo quantify the major environmental drivers of stream bacterial population dynamics, we modelled temporal differences in stream bacterial communities to quantify community shifts, including those relating to cyclical seasonal variation and more sporadic bloom events. We applied Illumina MiSeq 16S rRNA bacterial gene sequencing of 892 stream biofilm samples, collected monthly for 36‐months from six streams. The streams were located a maximum of 118 km apart and drained three different catchment types (forest, urban and rural land uses). We identified repeatable seasonal patterns among bacterial taxa, allowing their separation into three ecological groupings, those following linear, bloom/trough and repeated, seasonal trends. Various physicochemical parameters (light, water and air temperature, pH, dissolved oxygen, nutrients) were linked to temporal community changes. Our models indicate that bloom events and seasonal episodes modify biofilm bacterial populations, suggesting that distinct microbial taxa thrive during these events including non‐cyanobacterial community members. These models could aid in determining how temporal environmental changes affect community assembly and guide the selection of appropriate statistical models to capture future community responses to environmental change.

Antenatal Classes in the Context of Prenatal Anxiety and Depression during the COVID-19 Pandemic.

Perinatal maternal anxiety and depression negatively affect intrauterine fetal development, birth outcome, breastfeeding initiation, duration, and milk composition. Antenatal classes potentially reduce the anxiety of pregnant women and may thus contribute to healthy infant development. The study investigates the relationship between participation in online or in-person antenatal classes and levels of anxiety and depression in Polish women during the COVID-19 pandemic. The study group included 1774 adult, non-smoking pregnant women. We compared the state anxiety (STAI-State) and depression levels (EPDS) in women who (i) attended antenatal classes in-person, (ii) attended online classes, and (iii) did not attend any of them. The statistical analyses included a GLM model and trend analysis, while controlling for maternal trait anxiety, age, pregnancy complications, trimester of pregnancy, previous pregnancies, and COVID-19 infections. We observed statistically significant differences in the level of anxiety (and depression). Women who did attend antenatal classes in person had the lowest levels of anxiety and depression. Considering the importance of maternal mental well-being on fetal development, birth outcome, and breastfeeding, in-person participation in antenatal classes should be recommended to pregnant women.

Statistical Modelling of Road Traffic KSI Car Accidents in England (STATS19)

Several generalised linear models for counts (i.e., Poisson Model) as well as for binary response (i.e., Binary Logistic Model) and ordinal response (i.e., Ordinal Logistic Model) depending on selected multiple explanatory factors (discrete/ categorical) were developed for the road KSI car accidents in England based on STATS19 data (that were manipulated and several new factors were created), after exploratory exploration of discrete/ dichotomous/ nominal/ ordinal factors applied graphical EDA techniques followed by univariate ANOVA/ ANCOVA as well as MANOVA/ MANCOVA based on same selected multiple explanatory factors. Only the main effects as well as two-way interactions were investigated. Majority of main effects and several interaction effects in GLM models were found statistically significant with greater or lesser likelihood of having consequences. The statistically significant KSI car accident factors were identified and quantified for leading to aims to reduce as well as to prevent the car accident, particularly the killed or seriously injured car accidents. It also leads to inform the policymakers on how best to reduce the number and severity of car crashes.

Relationship between polymorphism within Peptidoglycan Recognition Protein 1 gene (PGLYRP1) and somatic cell counts in milk of Holstein cows

Abstract Bovine peptidoglycan recognition protein 1 (PGLY RP1) is an important receptor that binds to murein peptidoglycans (PGN) of Grampositive and Gram-negative bacteria and is, therefore, involved in innate immunity. The SNP T&gt;C rs68268284 located in the 1st exon of the PGLYRP1 gene was identified by the PCR-RFLP method in a population of 319 Holstein cows. Somatic cell count (SC) was measured 7–10 times in each of three completed lactations to investigate whether the PGLYRP1 polymorphism is associated with SC. Using the GLM model, it was found that cows with the TT genotype showed significantly lower somatic cell counts than those with the CC genotype during the first lactation (P = 0.023). Moreover, during lactations 1–2 and 1–3, cows with the TT genotype reveal significantly lower SCC than CT heterozygotes, at P = 0.025 and P = 0.006, respectively. Computer-aided analysis showed that rs68268284 polymorphism could modify the PGLY RP1 functions because the mutated residue is located in a domain that is important for the binding of other molecules.

Infant colic, young children\u2019s temperament and sleep in a population based longitudinal cohort study

BackgroundColic and sleep problems are common among infants, constitute challenges and distress for parents, and are often reasons for seeking help from health professionals. The literature debates whether infant colic and sleep problems are linked together or not. Further, limited evidence exists on how colic impacts on child temperament and sleep during early childhood. Thus, the purpose of this study was to increase our knowledge of the characteristics of infants with a history of colic compared to infants without, and to study how infant colic is associated with the development of child temperament and sleep over time.MethodsThe study is based on The Norwegian Mother, Father and Child Cohort Study (MoBa), a population-based cohort study conducted by the Norwegian Institute of Public Health. This sample contains 88,186 mothers and children. Data was retrieved from questionnaires distributed to mothers at recruitment (in pregnancy) and when the child was 6 months, 18 months, 3 years, and 5 years. Data was analysed using linear mixed models and GLM models for repeated measures.ResultsAt 6 months, infants with reported colic are described as fussier, present more sleeping problems, are breastfed less, and the families visit the child health centre more often when compared to the non-colic group. Mothers of children with reported colic perceive their children’s temperament significantly more challenging from the age of 6 months to 5 years. Further, children with reported colic were more likely to sleep less than recommended (22%) and to have more frequent night awakenings (14%) than usual for their age (6 months to 5 years).ConclusionInfant colic often occurs together with other signs of regulatory problems which may amplify the load on the parents. Moderate differences in temperament and sleep-problems across time, between those with colic and those without, indicate that the diagnosis of colic is moderately associated with later behavioural difficulties. However, it is demanding for the parents, and important to be aware of and act upon symptoms of colic in the child health centres to reduce the parents’ load and prevent adverse long-term outcomes.

Stochastic loss reserving with mixture density neural networks

In recent years, new techniques based on artificial intelligence and machine learning in particular have been making a revolution in the work of actuaries, including in loss reserving. A particularly promising technique is that of neural networks, which have been shown to offer a versatile, flexible and accurate approach to loss reserving. However, applications of neural networks in loss reserving to date have been primarily focused on the (important) problem of fitting accurate central estimates of the outstanding claims. In practice, properties regarding the variability of outstanding claims are equally important (e.g., quantiles for regulatory purposes).In this paper we fill this gap by applying a Mixture Density Network (“MDN”) to loss reserving. The approach combines a neural network architecture with a mixture Gaussian distribution to achieve simultaneously an accurate central estimate along with flexible distributional choice. Model fitting is done using a rolling-origin approach. Our approach consistently outperforms the classical over-dispersed model both for central estimates and quantiles of interest, when applied to a wide range of simulated environments of various complexity and specifications.We further extend the MDN approach by proposing two extensions. Firstly, we present a hybrid GLM-MDN approach called “ResMDN“. This hybrid approach balances the tractability and ease of understanding of a traditional GLM model on one hand, with the additional accuracy and distributional flexibility provided by the MDN on the other. We show that it can successfully improve the errors of the baseline ccODP, although there is generally a loss of performance when compared to the MDN in the examples we considered. Secondly, we allow for explicit projection constraints, so that actuarial judgement can be directly incorporated into the modelling process.Throughout, we focus on aggregate loss triangles, and show that our methodologies are tractable, and that they out-perform traditional approaches even with relatively limited amounts of data. We use both simulated data—to validate properties, and real data—to illustrate and ascertain practicality of the approaches.

Do the roadkills of different mammal species respond the same way to habitat and matrix?

While road network expansion connects human settlements between themselves, it also leads to deforestation and land use changes, reducing the connectivity between natural habitat patches, and increasing roadkill risk. More than 30% of registered mammal roadkills in Brazil are concentrated in four species: Cerdocyon thous (crab-eating fox); Euphractus sexcinctus (six-banded armadillo); Tamandua tetradactyla (collared anteater) and Myrmecophaga tridactyla (giant anteater), the latter being categorized as vulnerable by IUCN redlist. Our aim was to understand how these animals’ roadkills could be related to the land use proportions on landscapes all over the Brazilian territory, and investigate if the roadkill patterns differ among species. We collected secondary data on mammal roadkills (N = 2698) from several studies in different regions of Brazil. Using MapBiomas’ data on land use and land cover, we extracted landscape composition around each roadkill sample. Through the proportion of land use and land cover in the area of influence where the roadkill occurred, we built binomial GLM models and selected the best ones by Akaike Information Criteria. For crab-eating fox and the six-banded armadillo, the best models include matrix coverage resulting in increased roadkill risk, while both anteaters’ species have a habitat and a matrix component in their best models, with an interaction between the variables. These four species seem to be roadkilled in different landscape arrangements, but in all scenarios, anthropic areas had an important influence over the models. For habitat-dependent and more sensible species, such as Tamandua tetradactyla and Myrmecophaga tridactyla, the amount of matrix influencing the roadkill risk depends on habitat availability in the landscape. It changes the strength and direction of the effect according to the proportion of natural areas in the region, while with generalist species such as Cerdocyon thous and Euphractus sexcinctus, the quantity of human-modified coverage increases the risk.

Assessing Campylobacter cross-contamination of Danish broiler flocks at slaughterhouses considering true flock prevalence estimates and ad-hoc sampling

Campylobacter cross-contamination of Danish broiler flocks at slaughterhouses was investigated using data from two national surveillance components and from ad-hoc sampling. The animal level (AL) and food safety (FS) components from 2018 were compared. The AL component contained results of PCR on pools of cloacal swabs from 3,012 flocks processed at two Danish slaughterhouses (S1-S2), while the FS component regarded culture testing of leg skins from 999/3,012 flocks. The monthly “apparent” (AP) and “true” flock prevalence (TP) were estimated. Agreement between components was measured in percentage and in weighted-Kappa values. The relationship between the occurrence of cross-contamination (flock positive only in the FS component = cross-contaminated or CC, vs. flock negative in both components or NegBoth), slaughterhouse and surveillance period (quarter: Q1 to Q4) was evaluated by a generalized linear mixed effects (GLM) model. Thereafter, a linear mixed effects (LME) model was used to investigate the relationship between the level of meat contamination of carcass positive flocks (y = log10 colony forming units per gram, cfu/g), slaughterhouse, surveillance period, and flock type (CC vs. positive in both components or PosBoth). For both models, the farm was the random effect. Finally, in autumn 2019, ad-hoc field investigations were carried out testing caecal and neck skin samples, from two consecutive flocks at S1 and S2. Whole genome sequencing (WGS) was performed on isolates, for multilocus sequence typing (MLST) and single nucleotide polymorphisms (SNP) analysis. The monthly TP was always higher for the FS than for the AL component. Agreement between the components was substantial, but 8.1–8.6% of the flocks were CC. Those had median cfu/g 21–28 times lower than that of PosBoth flocks. In the GLM model, the explanatory variables were both significant (P-value <0.05). For example, the odds ratios (ORs) were 8.4 (95% CI: 4.0; 17.6) for Q3 vs. Q1, and 3.1 (1.8; 5.2) for S2 vs. S1. In the LME model, the flock type and the interaction between the other two variables, were significant. In the field study, a caecal positive flock was succeeded by an initially negative flock, in one out of five sampling sessions at S2. The cecal negative flock was positive in 58.3% of the neck skins with the isolate genetically similar to that from the caecal positive flock. Those results show that cross-contamination can be affected by surveillance periods and slaughterhouses, and it can contribute significantly to the TP of carcass positive flocks.

Association between NF-κB Signal Pathway-Related Gene Polymorphisms and Response to Alendronate Treatment in Postmenopausal Chinese Women with Low Bone Mineral Density.

Background Osteoporosis is a systemic bone disease characterized by reduction of bone content. Bisphosphonates are first-line treatments for osteoporosis, but they have variable effectiveness. Genetic factors may explain these differences. The NF-κB signaling pathway plays a key role in the regulation of bone metabolism. We aimed to determine whether genetic variations in the NF-κB signaling pathway affect the effectiveness of alendronate in postmenopausal Chinese women with low bone mass. Methods We recruited 455 postmenopausal Han Chinese women with primary osteoporosis or osteopenia aged 48–90 yrs who had experienced no spontaneous menses for at least 1 yr. All participants had dual X-ray absorptiometry (DEXA) bone mineral density (BMD) measurement at baseline and 1 yr after treatment. Treatment involved 1 yr administration of 70 mg oral alendronate weekly and 600 mg calcium and 125 IU of vitamin D daily. Thirteen tagSNPs in NF-κB1 (rs28362491, rs3774937, rs230521, rs230510, and rs4648068), RELA (rs7119750, rs11820062), and NLRC5 (rs289747, rs1566439, rs1684575, rs289726, rs289723, and rs41383) were chosen from the NCBI Locus Link and HapMap and genotyped individually. Genetic variation in these genes and the corresponding therapeutic response to alendronate treatment were analyzed. Results Among the 13 tagSNPs, rs289747 was significantly correlated with the BMD change rate at the femoral neck (P=0.048). This significance no longer existed after Bonferroni correction. We then performed principal component analysis (PCA) and found NLRC5 (rs289747 and rs1566439) were strongly correlated with alendronate efficacy in femoral phenotypes and were major components of BMD change values, particularly total hip and intertrochanteric phenotypes. Furthermore, the PLINK linear regression GLM model revealed that haplotype TT of RELA (rs7119750 and rs11820062) and ICCTA of NF-κB1 (rs28362491, rs3774937, rs230521, rs230510, and rs4648068) were associated with BMD of the total hip among each haplotype after 1 yr of treatment. Conclusion The NF-κB1, RELA, and NLRC5 genetic variations affect the therapeutic response of alendronate treatment for postmenopausal osteoporosis.