Unweighted Analysis Research Articles

Experiencing chronic cough symptoms for 3 years is associated with increased rates of healthcare resource use and higher healthcare costs in the United States compared to resolved chronic cough

Objective Chronic cough (CC) symptoms can persist as refractory or unexplained CC (RCC). We sought to characterize the clinical and economic burden of RCC. Methods In this retrospective US cohort study using data from Optum’s de-identified CDM Database (01/2015–03/2022), CC was identified as ≥1 CC diagnosis or ≥3 cough events (with ≥8 weeks and ≤120 days between the first and third events and ≥3 weeks between any 2 events). The index date was set as the earliest date of meeting the CC definition. The baseline period was defined as the 364 days prior to and including the index date. Adults with CC at baseline who met CC requirements (≥1 CC diagnosis, or ≥2 cough events occurring ≥8 weeks but ≤120 days apart) in both follow-up year 2 and follow-up year 3 were defined as having ‘3-year chronic cough’ (3YCC), a proxy measure of RCC, and compared to adults with CC at baseline who did not meet CC requirements in follow-up years 2 and 3 (non-3YCC). A propensity score weighting approach was used to adjust for baseline differences between the 3YCC and non-3YCC groups to compare clinical characteristics and healthcare resource use and costs in the two groups during the follow-up period. Results At baseline, the 3YCC group (N = 3,338) had significantly more comorbidities and higher all-cause healthcare resource use and costs than the non-3YCC group (N = 43,122) in unweighted analyses. After weighting, the groups (N = 3,338 with 3YCC and N = 3,145 without) were compared during a 3-year follow-up period. The 3YCC group had significantly more comorbidities, higher levels of all-cause healthcare resource use, and higher all-cause healthcare costs during the follow-up period compared to the non-3YCC group, after adjusting for baseline differences. For example, the mean total healthcare costs (in 2022 US dollars) were significantly higher among the 3YCC group than the non-3YCC group in each follow-up year, at $49,454 versus $42,144 in follow-up year 1, $49,339 versus $36,939 in follow-up year 2, and $51,737 versus $36,503 in follow-up year 3 (p<0.001 for each comparison). Conclusions After adjusting for baseline differences, persistent symptoms of CC were associated with significantly higher comorbidity, healthcare resource use, and healthcare costs compared to CC that resolved. Effective treatments for RCC would thus be expected to result in improved health as well as substantial healthcare cost offsets.

Real-life use of the PEXIVAS reduced-dose glucocorticoid regimen in granulomatosis with polyangiitis and microscopic polyangiitis

BackgroundThe PEXIVAS (Plasma exchange and glucocorticoids in severe antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis) trial showed that a reduced-dose glucocorticoid regimen (redGC) was non-inferior to a standard-dose regimen (standGC) with respect...

Exploring gut microbiota diurnal fluctuation in alcohol-dependent patients with sleep disturbance.

Introduction. Alcohol dependence (AD) and sleep disturbance (SD) independently affect gut microbiota, potentially disrupting the circadian rhythm of the microbiota and the host. However, the impact of SD on the composition and rhythmicity of gut flora in AD patients remains poorly understood.Gap Statement. Characteristics of gut flora and diurnal oscillations in AD patients experiencing SD are unknown.Aim. This study aims to explore alterations in gut flora and diurnal oscillations in AD patients experiencing SD.Methodology. Thirty-two AD patients and 20 healthy subjects participated, providing faecal samples at 7 : 00 AM, 11 : 00 AM, 3 : 00 PM and 7 : 00 PM for gut microbiota analysis using 16S rDNA sequencing. AD patients were further categorized into those with poor sleep (ADwPS) and those with good sleep (ADwGS) for further analyses.Results. The ADwPS group demonstrated elevated levels of anxiety, depression and withdrawal severity compared to the ADwGS group (all P<0.05). The β-diversity of gut microbiota in the ADwPS group differed from that in the ADwGS group (P<0.05). Bacterial abundances at various taxonomic levels, including Cyanobacteria and Pseudomonadales, differed between the ADwPS and ADwGS groups (all P<0.05). Utilizing unweighted UniFrac analysis, the β-diversity of gut microbiota in the ADwPS group demonstrated robust diurnal oscillation (P<0.05), whereas this pattern was statistically insignificant in the ADwGS group. Notably, the abundance of pathogenic bacteria like Pseudomonadales and Pseudomonadaceae exhibited marked diurnal fluctuation in the ADwPS group (all P<0.05).Conclusion. SD in AD patients extends beyond alcohol-induced alterations, impacting gut microbiota composition, function and diurnal oscillation patterns. This highlights its add-on influence, supplementing AD-related changes.

Metabolic syndrome in the setting of obesity: impact on in-hospital complications and outcomes after total knee and hip arthroplasty.

This study aims to evaluate the impact of metabolic syndrome in the setting of obesity on in-hospital outcomes and resource use after total joint replacement (TJR). A retrospective analysis was conducted using the National Inpatient Sample from 2006 to the third quarter of 2015. Discharges representing patients aged 40 years and older with obesity (BMI > 30 kg/m2) who underwent primary TJR were included. Patients were stratified into two groups with and without metabolic syndrome. The inverse probability of treatment weighting (IPTW) method was used to balance covariates. The obese cohort with metabolic syndrome was significantly older, more likely to be female, had higher rates of Medicare insurance, and more likely to be non-Hispanic Black than the obese cohort without metabolic syndrome. In the unweighted analysis, patients with obesity and metabolic syndrome were more likely to experience cardiac, gastrointestinal, genitourinary, and postoperative anemia complications, had a longer length of stay, and were less likely to be discharged home compared to obese patients without metabolic syndrome. After adjusting for covariates using IPTW, patients with obesity and metabolic syndrome were more likely to experience postoperative anemia complications only and had lower rates of home discharge, but there were no significant differences in any other complication variables or length of stay. Given the variability of metabolic health in obesity, the development of tailored perioperative protocols and recommendations acknowledging this variability in metabolic health in obese patients would ultimately potentially benefit patients and improve outcomes of TJR.

A-020 Evaluation of the QuidelOrtho Diagnostics Vitros NT-proBNP II Assay

Abstract Background N-terminal-proBNP (NT-proBNP), a short peptide originating from the cleavage of proBNP by Corin, can be used as a diagnostic test in individuals presenting with signs and symptoms consistent with heart failure (HF). QuidelOrtho Diagnostics released its latest reformulation of its NT-proBNP assay, the Vitros NT-proBNP II assay. The analytical performance of this assay was evaluated. Methods Repeatability, reproducibility, and carryover were assessed using quality control material. The analytical measuring range and clinical reportable range (AMR and CRR) were assessed using commercially available material and diluted patient samples. Accuracy was assessed by comparing results from the Vitros NT-proBNP II assay and results from the Vitros NT-proBNP assay. Instrument-to-instrument comparison was performed by comparing results from the NT-proBNP II assay from two different Vitros 5600 chemistry analyzers. Paired heparin and EDTA plasma samples were assessed for specimen type comparison. Results Repeatability and reproducibility were &amp;lt;=10% CV and no carryover was observed. The AMR was 20 - 30,000 pg/mL and the CRR extended the range to 600,000 pg/mL. Passing-Bablok analysis showed a significant proportional bias with a slope of 1.34 for samples up to 12,000 pg/mL (Vitros NT-proBNP). Vendor-performed comparison studies showed no significant proportional bias with a slope of 1.06 using unweighted Deming analysis for samples up to 20,700 pg/mL (Vitros NT-proBNP). Instrument-to-instrument and heparin-to-EDTA plasma comparisons showed no significant biases. Conclusions The NTproBNP II assay showed acceptable repeatability, reproducibility, and no carryover. The AMR analysis verified the measuring range in the IFU of the assay and the CRR is extended to 600,000 pg/mL. Results were very comparable between two different Vitros 5600s and between paired heparin and EDTA plasma specimens. Comparison between the Vitros NT-proBNP and Vitros NT-proBNP II assays showed a very significant proportional bias (slope of 1.34) for specimens up to 12,000 pg/mL measured on the Vitros NT-proBNP assay, but the proportional bias is less significant at higher NT-proBNP values (&amp;gt;20,000 pg/mL, Vitros NT-proBNP) are included in the analysis. There may be a significant matrix effect or interference at lower NT-proBNP concentrations with the reformulated reagent, which may be less prominent when NT-proBNP is present at much higher concentrations.

The Influence of X-ray Radiation on the Morphological, Biochemical, and Molecular Changes in Copiapoa tenuissima Seedlings

Cactaceae are a significant group of ornamental plants in the horticultural market. In the present study, X-rays were used for the first time to induce mutational changes in the cactus Copiapoa tenuissima. The aim of this study was to assess the genetic variability in seedlings exposed to in vitro X-ray irradiation at doses of 0, 15, 20, 25, and 50 Gy (radiation time from 5 min 13 s to 17 min 22 s) by morphological analysis, a spectrophotometric evaluation of plant pigment content, and the confirmation of changes at the genetic level using SCoT (start codon targeted) markers. The results showed that the percentage of colorful seedlings increased with the radiation dose and was the highest for the 50 Gy dose (4.89%). The radiation doses of 25 and 50 Gy generated seedlings with a new color (orange-brown), which had not yet been observed in C. tenuissima. With the increase in the radiation dose, as compared to control seedlings, brown seedlings showed an increase in the concentrations of carotenoids, chlorophyll a, and chlorophyll b, while green seedlings showed an increase in the concentrations of anthocyanins and chlorophyll b and a decrease in the concentrations of carotenoids and chlorophyll a. The unweighted pair group method analysis showed a very large genetic distance among the tested genotypes exposed to X-rays. The results of the present study provide a novel direction for using X-rays to breed new cultivars of C. tenuissima.

Frailty index is an independent predictor of all-cause and cardiovascular mortality in Eastern Europe: a multicentre cohort study

BackgroundThis study investigates the association between frailty and mortality in Eastern European populations, which remains largely unexplored compared with Western Europe. The aim is to assess the risk of all-cause...

Gut microbiota compositions in the carriers and noncarriers of third-generation cephalosporin–resistant Escherichia coli: A study among children in southern Taiwan

BackgroundAntimicrobial resistance, particularly in third-generation cephalosporin–resistant (3GC-R) Escherichia coli (E. coli), poses major global health challenges and has various clinical implications. Researchers have explored the relationship between extended-spectrum β-lactamase–producing E. coli and gut microbiota composition, which influence host health and disease susceptibility, in adults. In this study, we analyzed gut microbiota composition in Taiwanese children by the colonization status of 3GC-R E. coli. MethodsThis cross-sectional study included children (age, 0–6 years) from Kaohsiung, Taiwan. Fecal samples were subjected to microbiological and gut microbiome (full-length 16S rRNA sequencing) analyses. The antimicrobial susceptibility of E. coli colonies isolated from the samples was tested. Furthermore, gut microbiota compositions and diversity indices were compared between 3GC-R E. coli carriers and noncarriers. ResultsApproximately 46% of all children aged <6 years carried 3GC-R E. coli. The abundances of Drancourtella, Romboutsia, and Desulfovibrio (genus level) were higher in carriers than in noncarriers. By contrast, the abundances of Odoribacteraceae (family level) and Sutterella (genus level) were higher in noncarriers than in carriers. No significant between-group difference was observed in alpha diversity. However, a significant between-group difference was noted in beta diversity (unweighted UniFrac analysis). ConclusionThis is the first study that investigated differences in the gut microbiota between healthy 3GC-R E. coli carriers and noncarriers in children, suggesting potential mechanisms involving altered utilization of short-chain fatty acids and elevated succinate levels contributing to increased colonization of 3GC-R E. coli. The other taxa identified in this study may contribute to colonization resistance in the pediatric population.

CLUSTER ANALYSIS OF YEARLING BODY WEIGHT OF SHEEP OF NORTHERN NIGERIA AND THEIR CROSSES

Clumping structure of yearling body weight among sheep of Northern Nigeria and their crosses was investigated using cluster analysis. Body weights of 65 yearling sheep were also analyzed using General Linear Model procedure of SAS. Distances were used to construct dendrogram using the Unweighted Pairs Group Method Analysis implemented in R 2.13.0 package. TREE procedure that prints the dendrogram based on the distances between the clusters was introduced in PROC CLUSTER procedure. Yearling genotype affected BWT_12 (P&lt;0.05). The pure Balami yearling (BL X BL) had the highest body weight at 12 months (29.10±4.02 kg). Yearling produced from Balami- sired mating with Yankasa ewe had the next heaviest weight (24.00±2.84 kg). This was followed in the third ranking when Balami was as the dam and Uda was used as the sire (20.50±4.02 kg). The least overall weight at 12 months of age was recorded when Yankasa was used as the sire on Balami ewe (15.12±4.02 kg). The BWT_12 recorded for YK x YK (14.79±0.80 kg) was similar (P&gt;0.05) to what was obtained when Yankasa was used as sire on Balami ewe. Sheep of Northern Nigeria and their crosses were grouped into two clusters at distance 2.656 on the basis of body weight of the yearling sheep. Pure Balami (BL X BL) formed the first cluster while the rest of the genotypes belong to the second cluster. The yearling body weight of Balami was superior to that of other genotypes. The cluster analysis grouped pure Balami yearling distinctly from other genotypes. Improvement programmes of Nigerian sheep breeds should consider exploitation of the genetic potentials of Balami rams and ewes in terms of fast growth rate.

CHARACTERIZATION OF DONKEYS IN NORTH WEST NIGERIA USING COAT COLOUR AND HAIR TYPES

One hundred donkeys were sampled from each of Sokoto, Jigawa, Kano, Katsina, Kaduna, Zamfara and Kebbi State to make a total of 700 sample size for characterization of domestic donkeys in North- West Nigeria using coat colour and hair types among Red (Auraki), Black (Duni), White (Fari) and Brown (Idabari) strains of donkeys. Coat colour and hair types of donkeys was tabulated using frequency procedure while their distribution was tested using Chi Square of SAS. Distances were used to construct a dendogram using the Unweighted Pairs Group Method Analysis implemented in R 2.13.0. Coat colours and hair types were significantly (P&lt;0.01) distributed among donkeys in the studied population. The most prominent coat colour observable among donkeys in North West of Nigeria was Brown (86%) with confidence level between 85 and 87%. The most occurring hair type was short-smooth (75%) with confidence interval between 71 and 78%. The other variants of coat colours were short-rough (14%) and long-curly (11%). Two major clusters were formed. The first cluster showed close relationship between Red (Auraki) and Black (Duni) donkeys. The second cluster was further divided into two sub-groups with Brown (Idabari) as leader and White (Fari) as joiner. The dendogram indicated that the Idabari-Fari was more closely related with Idabari than with Fari and also indicated that Auraki and Duni are closer and similar for hair type but are distant from Idabari, Idabari-fari and Fari. Apart from coat colour, classification of donkeys on the basis of hair type should be developed using morphological, biochemical and molecular techniques.

Application of information from external data to correct for collider bias in a Covid-19 hospitalised cohort

BackgroundThroughout the Covid-19 pandemic, researchers have made use of electronic health records to research this disease in a rapidly evolving environment of questions and discoveries. These studies are prone to collider bias as they restrict the population of Covid-19 patients to only those with severe disease. Inverse probability weighting is typically used to correct for this bias but requires information from the unrestricted population. Using electronic health records from a South London NHS trust, this work demonstrates a method to correct for collider bias using externally sourced data while examining the relationship between minority ethnicities and poor Covid-19 outcomes.MethodsThe probability of inclusion within the observed hospitalised cohort was modelled based on estimates from published national data. The model described the relationship between patient ethnicity, hospitalisation, and death due to Covid-19 – a relationship suggested to be susceptible to collider bias. The obtained probabilities (as applied to the observed patient cohort) were used as inverse probability weights in survival analysis examining ethnicity (and covariates) as a risk factor for death due to Covid-19.ResultsWithin the observed cohort, unweighted analysis of survival suggested a reduced risk of death in those of Black ethnicity – differing from the published literature. Applying inverse probability weights to this analysis amended this aberrant result to one more compatible with the literature. This effect was consistent when the analysis was applied to patients within only the first wave of Covid-19 and across two waves of Covid-19 and was robust against adjustments to the modelled relationship between hospitalisation, patient ethnicity, and death due to Covid-19 made as part of a sensitivity analysis.ConclusionsIn conclusion, this analysis demonstrates the feasibility of using external publications to correct for collider bias (or other forms of selection bias) induced by the restriction of a population to a hospitalised cohort using an example from the recent Covid-19 pandemic.

Nexus between investor returns of Nigerian deposit money banks and integrated reporting with the moderating role of profit after tax

Integrating reporting strives to address issues with corporate reporting procedures and hold businesses responsible for their local surroundings, as well as additional stakeholders impacted by their operations in producing returns for investors. This study employed Nigerian deposit money banks to examine whether investor returns with profit after tax and integrated reporting are statistically and significantly related. Ex post facto research methodology was applied. Purposive sampling was used to sample ten Nigerian deposit money banks. Data were taken from the annual reports of the chosen banks. The international integrated reporting framework of 2021 checklist was utilized to extract integrated reporting data using the unweighted content analysis method. The integrated reporting disclosure index was used as a proxy for integrated reporting. Market price per share, dividend per share, and price-earnings ratio were used as proxies for investor returns. Profit after tax was used as a moderating variable. The results indicate that with the moderating variable, which is Profit after tax, integrated reporting and price-earnings ratio are related to coefficients of 9.9585. Integrated reporting and dividend per share are related to coefficients of 3.151612. Integrated reporting and market price per share are related to coefficients of 36.7535. Dividend per share and integrated reporting disclosure are significantly related to p-values of 0.001. Market price per share and integrated reporting disclosure are significantly related to p-values of 0.002. This study concluded that integrated reporting and investor returns are statistically and significantly related to the moderating role of Profit after tax of Nigerian deposit money banks. AcknowledgmentThe involvement of those who helped make this study successful is acknowledged below. We appreciate your involvement.

Comparison of the effects of cefmetazole and meropenem on microbiome: A pilot study

BackgroundCefmetazole (CMZ) is a carbapenem-sparing option in the treatment of extended-spectrum beta-lactamase (ESBL)-producing bacterial infection. In this pilot study, we aimed to compare the effects of antimicrobial treatment (meropenem [MP] and CMZ) with those of no antimicrobial treatment (control group) on the microbiome. MethodsThe study was a multicenter, prospective, observational pilot study conducted from October 2020 to October 2022. Feces and saliva samples were collected for microbiome analyses at two time points (early-period: days 1–3; and late-period: days 4–30) for the antimicrobial treatment group, and at one time point for the control group. ResultsFive feces (MP-F and CMZ-F) and five saliva (MP-S and CMZ-S) samples were included in the MP and the CMZ groups. Ten feces (C–F) and saliva (C–S) samples were included in the control group. Group α diversity was notably lower in the late-period MP-F group than the control group as determined with the Shannon richness index. β diversity analysis of the feces samples based on weighted and unweighted UniFrac distances revealed distinctions in both the late-period CMZ-F and MP-F groups compared with the control group. Weighted UniFrac analysis showed that only the early-period MP-F group differed from the control group. In the saliva samples, weighted and unweighted UniFrac analyses showed significant differences between the control group and the early CMZ, late CMZ, and late MP groups. ConclusionsMP treatment may cause larger impact on the feces microbiome than CMZ in Japanese patients.

Validation and Standardization of a Questionnaire for the Self-Assessment of Service-Learning Experiences in Higher Education (QaSLu-27)

There has been a proliferation of service-learning practices in many disciplines of higher education. Although there are many instruments to assess various aspects related to service-learning, only a few are valid and reliable. This research tries to fill that gap by providing an optimal instrument. To this end, 118 educators from 43 higher education institutions participated in the validation process. Sampling was incidental and based on opportunity. Participants were asked to fill in the Questionnaire for the Self-assessment of University Service-learning Experiences—45 (QaSLu-45), which consists of 45 items with a 5-point Likert scale and was validated qualitatively through the Delphi method in 2020. To validate the questionnaire psychometrically, four steps were followed. First, an exploratory factor analysis of the main components was performed. Next, robust unweighted least squares factor exploratory analysis was carried out. Then, the goodness-of-fit and reliability of the final questionnaire were calculated. Finally, the scales for the new reduced QaSLu-27 were established. These results provide a valid, robust, reliable instrument, the QaSLu-27, which not only facilitates the evaluation of service-learning experiences for improving teaching and learning processes but can also be useful for their design.

The association between the non-high-density lipoprotein cholesterol to high-density lipoprotein cholesterol ratio and the risk of osteoporosis among U.S. adults: analysis of NHANES data

BackgroundOsteoporosis and atherosclerosis frequently afflict older adults, and recent insights suggest a deeper connection between these conditions that surpasses mere aging effects. The ratio of non-high-density to high-density lipoprotein cholesterol (NHHR) has emerged as a novel lipid marker for evaluating the risk of cardiovascular diseases. Nonetheless, investigations into the correlation of the NHHR with the risk of developing osteoporosis remain unexplored.MethodsWe collected NHHR and bone mineral density (BMD) data from 11,024 National Health and Nutrition Examination Survey (NHANES) participants between 2011 and 2018. Multivariate linear regression was employed to examine the correlation between BMD and NHHR. Smooth curves were employed to deal with the nonlinearity. To further account for the nonlinear link, we used a two-part linear regression model. The threshold effects were estimated using two components of a linear regression model. Subgroup and sensitivity analyses were carried out to ascertain the stability of the findings.ResultsWe discovered a negative relationship between the NHHR and lumbar spine BMD in all three models. An L-shaped curvilinear association existed between the NHHR and lumbar spine BMD, with a key inflection point of 6.91. The fully adjusted model showed that the BMD of the lumbar spine fell by 0.03 g/cm2 in those who were in the fourth quartile as opposed to the lowest quartile. The sensitivity analysis using unweighted logistic analysis verified the stability of the results. In addition, BMD in the nondiabetic group was more significantly affected by the negative effect of the NHHR in the subgroup analysis.ConclusionsAccording to this research, there appears to be a negative correlation between BMD and NHHR in US Adults. To clarify the precise physiological mechanisms by which the NHHR contributes to the onset of osteoporosis, more research is necessary.

The vaginal microbiota of healthy female cats

The vaginal microbiota of the queen (i.e., female cat) has never been described using culture independent methods. The objectives of the present research were to describe the vaginal microbiota of healthy domestic shorthair queens using both 16S rRNA sequencing and culture, and to assess the effects of age, living environment, and reproductive season on its composition. Thirty queens undergoing elective ovariectomy were included in the study. The vaginal samples were collected just before surgery, from animals under general anaesthesia. Two consecutive mini-swabs were introduced in the queens' vaginal tract. A preliminary study with 10 healthy queens aimed to negate sampling order's effect. Two consecutive samples for sequencing (5 queens, 10 swabs) and culture (5 queens, 10 swabs) were collected, confirming a match (100 % in culture, Bray-Curtis P = 0.96 in sequencing). The experiment included 20 queens that were prospectively grouped based on age (prepubertal N = 10, adult N = 10), living environment (indoor N = 10, outdoor N = 10), and time of the year, whether during the reproductive season (N = 10) or during seasonal anoestrous (N = 10). Bacteria were identified through metataxonomic analysis, amplifying the V1–V2 regions of 16S rRNA gene, and through standard culture followed by MALDI-TOF MS.The feline vaginal microbiota is dominated by Proteobacteria, Firmicutes, Bacteroidota, and Actinobacteria. Escherichia-Shigella, Streptococcus, and Pasteurella were the most abundant genera. Although culture underestimated bacterial richness and diversity compared to sequencing, Escherichia and Streptococcus were the most isolated bacteria. No bacterial growth was observed in 15 % of samples (N = 3/20), whereas growth of one or two bacterial species was observed in 64.7 % (N = 11/17) and 35.3 % (N = 6/17) of cases, respectively. No differences in terms of alpha (Kruskal-Wallis rank sum test P = 0.65) and beta diversity (Bray-Curtis, Unweighted and Weighted UniFrac analyses P > 0.5) were observed. Although a difference in alpha diversity based on phylogenetic tree (P = 0.02) was detected between indoor and outdoor queens. In conclusion, mixed and monoculture of Escherichia coli, Streptococcus canis, Staphylococcus felis, and Enterococcus spp. are normal findings within the cat vagina. Age and reproductive season do not influence the feline vaginal microbiota, whereas further research is needed to elucidate the role of the living environment.

Estimation of the causal effect of sex on neonatal intensive care unit outcomes among very low birth weight infants.

Estimate the causal effect of sex on outcomes in the neonatal intensive care unit (NICU) among very low birth weight (VLBW) infants. Retrospective cohort study using Vermont Oxford Network data to compare NICU outcomes for VLBW males versus females. Odds ratios (OR) for outcomes that differed significantly by sex were computed using standard unweighted analysis and inverse probability weighted (IPW) analysis to correct for selection bias. Using standard analysis, males were significantly more likely to die before discharge and experience six other adverse outcomes. From IPW analysis, male sex caused a 56% increase in the odds of death before discharge (OR = 1.56, 95% confidence interval: 1.18-1.94). Standard unweighted results were significantly biased towards increased risk of adverse outcomes for males (p = 0.005) compared to IPW results for which three outcomes were no longer significantly associated with male sex. Standard statistical methods generally overestimate the casual effect of sex among VLBW infants.

A Dynamics-Weighted Principal Components Analysis of Dominant Atmospheric Drivers of Ocean Variability with an Application to the North Atlantic Subpolar Gyre

Abstract This paper describes a framework for identifying dominant atmospheric drivers of ocean variability. The method combines statistics of atmosphere–ocean fluxes with physics from an ocean general circulation model to derive atmospheric patterns optimized to excite variability in a specified ocean quantity of interest. We first derive the method as a weighted principal components analysis and illustrate its capabilities in a toy problem. Next, we apply our analysis to the problem of interannual upper ocean heat content (HC) variability in the North Atlantic Subpolar Gyre (SPG) using the adjoint of the MITgcm and atmosphere–ocean fluxes from the ECCOv4-r4 state estimate. An unweighted principal components analysis reveals that North Atlantic heat and momentum fluxes in ECCOv4-r4 have a range of spatiotemporal patterns. By contrast, dynamics-weighted principal components analysis collapses the space of these patterns onto a small subset—principally associated with the North Atlantic Oscillation—that dominates interannual SPG HC variance. By perturbing the ECCOv4-r4 state estimate, we illustrate the pathways along which variability propagates from the atmosphere to the ocean in a nonlinear ocean model. This technique is applicable across a range of problems across Earth system components, including in the absence of a model adjoint. Significance Statement While the oceans have absorbed 90% of the excess heat associated with human-forced climate change, the change in the ocean’s heat content is not steady, with peaks and troughs superimposed upon a general increase. These fluctuations come from chaotic changes in the atmosphere and ocean and can be hard to disentangle. We use this case of ocean heat content variability to introduce a new method for determining the patterns of weather and climate in the atmosphere that are most effective at generating fluctuations in the ocean. To do this, we combine the statistics of recent atmospheric activity with output from a state-of-the-art numerical ocean model that reveals physical processes driving changes in ocean quantities including ocean heat content. This approach suggests that the atmospheric patterns that stimulate the most energetic changes in ocean heat content in the northern North Atlantic are not necessarily the most energetic patterns present in the atmosphere. We test our findings by preventing these patterns from affecting the ocean in our numerical model and measure a strong reduction in ocean heat content fluctuations.

Stability and unweighted L1-gain analysis for switched time-delay positive systems with stable and unstable subsystems

This article investigates the stability and unweighted L1-gain analysis of switched time-delay positive systems (STDPSs) with stable and unstable subsystems. The persistent dwell time (PDT) switching is considered for the first time, which is more general compared with the typical dwell time (DT) or average dwell time (ADT) techniques. Under the PDT switching, the activation time of an unstable subsystem is less than an upper bound instead of greater than a given constant, which makes it easier to achieve stability in practice. Considering the stable and unstable subsystems, a piecewise multiple co-positive Lyapunov–Krasovskii functional is constructed to obtain the stability criterion of the STDPSs. Subsequently, the unweighted L1-gain for STDPSs is explored, which has explicit physical meaning compared with the weighted results and can be calculated by solving the linear programming problem. Finally, a water-quality model and a numerical example are provided to indicate the validity of the proposed methods.

Diversity of Banana Plant Types (Musa spp) in Kuala Dua Village, Sungai Raya District, Kubu Raya Regency

This research aims to determine the diversity and relationships of banana varieties (Musa spp) based on morphological characters. This research was conducted from January to April 2023 in 4 hamlets, namely Dusun Keramat 1, Dusun Keramat ll, Dusun Karya l, and Dusun Kary ll in Kuala Dua Village, Sungai Raya District, Kubu Raya Regency, West Kalimantan. There were 41 morphological characters observed including vegetative, generative and quantitative characters. Analysis of kinship relationships using the UPGMA (Unweighted Pair-wise Multivariate Analysis) method with the NTSYS ver 2.0 application is presented in the form of a dendrogram. In this research, 13 varieties were obtained, namely kapok bananas, crew bananas, 40 day bananas, cavendish bananas, green cooking bananas, chestnut bananas, mas bananas, Malaysian bananas, king bananas, areca nut bananas, Ambon bananas, red kak bananas, and prawn bananas. The results of the grouping analysis showed that 13 banana varieties had a similarity level of 39% and formed two main groups, namely groups A and B. Group A consisted of kapok bananas, crew bananas, red kak bananas, chestnut bananas, king bananas, areca nut bananas and prawn bananas. Group B consists of 40 day bananas, mas bananas, cavendish bananas, green ripe bananas and Malaysian bananas. At a similarity level of 83%, each banana variety forms a group within its respective variety.