Large Variation Research Articles

Establishment of Diagnostic Reference Levels in Portuguese Interventional Radiology departments

PurposeTo establish Portuguese Diagnostic Reference Levels (DRLs), for six body fluoroscopy guided interventional procedures (FGIP). MethodA retrospective study was conducted in five interventional departments most representative of Interventional Radiology (IR) practice. Dose values, in terms of air kerma area product (PKA in Gy.cm2), air kerma at the patient entrance reference point (Ka,r in mGy), and exposure parameters (fluoroscopy time (FT) and number of cine runs) were collected. Examinations were selected per procedure (at least 20), according to the antero-posterior and lateral diameter mean value (±5 cm), measured on previous Computed Tomography (CT) examinations. ResultsData of 489 body FGIP show a large variation on dose values per procedure and per department. National DRLs in terms of PKA were 20.2 Gy.cm2 for Percutaneous transhepatic biliary drainage (PTBD), 98.2 Gy.cm2 for Bronchial artery embolisation (BAE), 247.7 Gy.cm2 for Transarterial chemoembolisation (TACE), 331.6 Gy.cm2 for Inferior epigastric arteries embolisation (IEAE), 312.0 Gy.cm2 for Transjugular intrahepatic portosystemic shunt (TIPS) and 19.3 Gy.cm2 for Endovascular treatment of femoral popliteal arteries (ETFPA). ConclusionsThis is the first study reporting Interventional Radiology DRLs in Portugal and we propose preliminary national estimates for the six more common body FGIP. The results of this study will be presented and discussed with all Portuguese IR departments, to promote procedures optimisation.

Spatial variation and controls of soil microbial necromass carbon in a tropical montane rainforest

Soil microbial necromass carbon is an important component of the soil organic carbon (SOC) pool which helps to improve soil fertility and texture. However, the spatial pattern and variation mechanisms of fungal- and bacterial-derived necromass carbon at local scales in tropical rainforests are uncertain. This study showed that microbial necromass carbon and its proportion in SOC in tropical montane rainforest exhibited large spatial variation and significant autocorrelation, with significant high-high and low-low clustering patterns. Microbial necromass carbon accounted for approximately one-third of SOC, and the fungal-derived microbial necromass carbon and its proportion in SOC were, on average, approximately five times greater than those of bacterial-derived necromass. Structural equation models indicated that soil properties (SOC, total nitrogen, total phosphorus) and topographic features (elevation, convexity, and aspect) had significant positive effects on microbial necromass carbon concentrations, but negative effects on its proportions in SOC (especially the carbon:nitrogen ratio). Plant biomass also had significant negative effects on the proportion of microbial necromass carbon in SOC, but was not correlated with its concentration. The different spatial variation mechanisms of microbial necromass carbon and their proportions in SOC are possibly related to a slower accumulation rate of microbial necromass carbon than of plant-derived organic carbon. Geographic spatial correlations can significantly improve the microbial necromass carbon model fit, and low sampling resolution may lead to large uncertainties in estimating soil carbon dynamics at specific sites. Our work will be valuable for understanding microbial necromass carbon variation in tropical forests and soil carbon prediction model construction with microbial participation.

Concurrently assessing water supply and demand is critical for evaluating vulnerabilities to climate change

AbstractAligning water supply with demand is a challenge, particularly in areas with large seasonal variation in precipitation and those dominated by winter precipitation. Climate change is expected to exacerbate this challenge, increasing the need for long‐term planning. Long‐term projections of water supply and demand that can aid planning are mostly published as agency reports, which are directly relevant to decision‐making but less likely to inform future research. We present 20‐year water supply and demand projections for the Columbia River, produced in partnership with the Washington State Dept. of Ecology. This effort includes integrated modeling of future surface water supply and agricultural demand by 2040 and analyses of future groundwater trends, residential demand, instream flow deficits, and curtailment. We found that shifting timing in water supply could leave many eastern Washington watersheds unable to meet late‐season out‐of‐stream demands. Increasing agricultural or residential demands in watersheds could exacerbate these late‐season vulnerabilities, and curtailments could become more common for rivers with federal or state instream flow rules. Groundwater trends are mostly declining, leaving watersheds more vulnerable to surface water supply or demand changes. Both our modeling framework and agency partnership can serve as an example for other long‐term efforts that aim to provide insights for water management in a changing climate elsewhere around the world.

Exploring the nutritional potentials of wild Vigna legume species for neo-domestication prospects

AbstractProjected increases in human population suggest that 70% more food will be needed in the near future, this makes it imperative to search for alternative food and feed sources for human and animal nutrition to feed the exponentially growing human population. According to the FAO 2019 report, the immense challenge of achieving the Zero Hunger target by 2030 is persistent. Exploring the unexplored, refining unrefined traits, cultivating the uncultivated, and popularizing the unpopular remain the most adequate steps proposed by researchers to achieve the domestication of the undomesticated for food and nutrition security. In that line of thought, this study explored the proximate composition of 87 accessions of four wild unexplored Vigna species (V. racemosa, V. ambacensis, V. reticulata, V. vexillata) in order to reveal information leading to their future domestication and utilization. Standard procedures and methods approved by the Association of Official Analytical Chemists were used in carrying out the proximate composition (%protein, %lipid, %fibre, %ash and % moisture and % carbohydrate) of the wild Vigna legumes. The study revealed that the wild Vigna species possess a large variation range of nutrient characteristics which could be exploited in the improvement of domesticated species or guide their domestication. It was also found that some individual wild accessions have higher nutrient, content as compared with domesticated ones which could be advantageous for bio-fortification or domestication. Indications relating to the candidate accessions favourable for domestication, based on the nutrient characteristics were revealed.

Exploration of differential responses to FODMAPs and gluten in people with irritable bowel syndrome- a double-blind randomized cross-over challenge study

IntroductionThere is large variation in response to diet in irritable bowel syndrome (IBS) and determinants for differential response are poorly understood.ObjectivesOur aim was to investigate differential clinical and molecular responses to provocation with fermentable oligo-, di-, monosaccharides, and polyols (FODMAPs) and gluten in individuals with IBS.MethodsData were used from a crossover study with week-long interventions with either FODMAPs, gluten or placebo. The study also included a rapid provocation test. Molecular data consisted of fecal microbiota, short chain fatty acids, and untargeted plasma metabolomics. IBS symptoms were evaluated with the IBS severity scoring system. IBS symptoms were modelled against molecular and baseline questionnaire data, using Random Forest (RF; regression and clustering), Parallel Factor Analysis (PARAFAC), and univariate methods.ResultsRegression and classification RF models were in general of low predictive power (Q2 ≤ 0.22, classification rate < 0.73). Out of 864 clustering models, only 2 had significant associations to clusters (0.69 < CR < 0.73, p < 0.05), but with no associations to baseline clinical measures. Similarly, PARAFAC revealed no clear association between metabolome data and IBS symptoms.ConclusionDifferential IBS responses to FODMAPs or gluten exposures could not be explained from clinical and molecular data despite extensive exploration with different data analytical approaches. The trial is registered at www.clinicaltrials.gov as NCT03653689 31/08/2018.

Neurological outcomes and mortality after neonatal seizures with electroencephalographical verification. A systematic review

AimTo conduct a systematic review of post-neonatal neurological outcomes and mortality following neonatal seizures with electroencephalographical verification. MethodsThe databases Medline, Embase and Web of Science were searched for eligible studies. All abstracts were screened in a blinded fashion between research team members and reports found eligible were obtained and screened in full text by two members each. From studies included, outcome results for post-neonatal epilepsy, cerebral palsy, intellectual disability, developmental delay, mortality during and after the neonatal period and composite outcomes were extracted. A quality assessment of each study was performed. ResultsIn total, 5518 records were screened and 260 read in full text. Subsequently, 31 studies were included, containing cohorts of either mixed or homogenous etiologies. Follow-up time and gestational ages varied between studies. No meta-analysis could be performed due to the low number of studies with comparable outcomes and effect measures. Reported cumulative incidences of outcomes varied greatly between studies. For post-neonatal epilepsy the reported incidence was 5–84%, for cerebral palsy 9–78%, for intellectual disability 24–67%, for developmental delay 10–67% and for mortality 1–62%. Subgroup analysis had more coherent results and in cohorts with status epilepticus a higher incidence of post-neonatal epilepsy from 46 to 84% was shown. ConclusionThe large variation of reported incidences for neurological outcomes and mortality found even when restricting to cohorts with electroencephalographically verified neonatal seizures indicates selection bias as a significant confounder in existing studies. Population-based approaches are thus warranted to correctly predict outcomes in this group.

Underreporting of non-study cigarette use by study participants confounds the interpretation of results from ambulatory clinical trial of reduced nicotine cigarettes

BackgroundAs part of its comprehensive plan to significantly reduce the harm from tobacco products, the US Food and Drug Administration is establishing a product standard to lower nicotine in conventional cigarettes to make them “minimally addictive or non-addictive". Many clinical studies have investigated the potential impact of such a standard on smoking behavior and exposure to cigarette constituents. These ambulatory studies required participants who smoke to switch to reduced nicotine study cigarettes. In contrast to clinical trials on pharmaceuticals or medical devices, participants had ready access to non-study conventional nicotine cigarettes and high rates of non-study cigarette use were consistently reported. The magnitude of non-compliance, which could impact the interpretation of the study results, was not adequately assessed in these trials.MethodsWe conducted a secondary analysis of data from a large, randomized trial of reduced nicotine cigarettes with 840 participants to estimate the magnitude of non-compliance, i.e., the average number of non-study cigarettes smoked per day by study participants assigned to reduced nicotine cigarettes. Individual participants’ non-study cigarette use was estimated based on his/her urinary total nicotine equivalent level, the nicotine content of the study cigarette assigned and the self-reported number of cigarettes smoked, using a previously published method.ResultsOur analysis showed that (1) there is a large variation in the number of non-study cigarettes smoked by participants within each group (coefficient of variation 90–232%); (2) participants in reduced nicotine cigarette groups underreported their mean number of non-study cigarettes smoked per day by 85–91%; and (3) the biochemical-based estimates indicate no reduction in the mean number of total cigarettes smoked per day for any group assigned to reduced nicotine cigarettes after accounting for non-study cigarettes.ConclusionsHigh levels of non-compliance, in both the rate and magnitude of non-study cigarette use, are common in ambulatory reduced nicotine cigarette trials where participants have access to conventional nicotine non-study cigarettes. The potential impact of high non-compliance on study outcomes should be considered when interpreting the results from such ambulatory studies.

Template-specific optimization of NGS genotyping pipelines reveals allele-specific variation in MHC gene expression.

Using high-throughput sequencing for precise genotyping of multi-locus gene families, such as the major histocompatibility complex (MHC), remains challenging, due to the complexity of the data and difficulties in distinguishing genuine from erroneous variants. Several dedicated genotyping pipelines for data from high-throughput sequencing, such as next-generation sequencing (NGS), have been developed to tackle the ensuing risk of artificially inflated diversity. Here, we thoroughly assess three such multi-locus genotyping pipelines for NGS data, the DOC method, AmpliSAS and ACACIA, using MHC class IIβ data sets of three-spined stickleback gDNA, cDNA and "artificial" plasmid samples with known allelic diversity. We show that genotyping of gDNA and plasmid samples at optimal pipeline parameters was highly accurate and reproducible across methods. However, for cDNA data, the gDNA-optimal parameter configuration yielded decreased overall genotyping precision and consistency between pipelines. Further adjustments of key clustering parameters were required tο account for higher error rates and larger variation in sequencing depth per allele, highlighting the importance of template-specific pipeline optimization for reliable genotyping of multi-locus gene families. Through accurate paired gDNA-cDNA typing and MHC-II haplotype inference, we show that MHC-II allele-specific expression levels correlate negatively with allele number across haplotypes. Lastly, sibship-assisted cDNA-typing of MHC-I revealed novel variants linked in haplotype blocks, and a higher-than-previously-reported individual MHC-I allelic diversity. In conclusion, we provide novel genotyping protocols for the three-spined stickleback MHC-I and -II genes, and evaluate the performance of popular NGS-genotyping pipelines. We also show that fine-tuned genotyping of paired gDNA-cDNA samples facilitates amplification bias-corrected MHC allele expression analysis.

Surgical Aspects of Sleeve Gastrectomy Are Related to Weight Loss and Gastro-esophageal Reflux Symptoms

IntroductionA large variation in outcome has been reported after sleeve gastrectomy (SG) across countries and institutions. We aimed to evaluate the effect of surgical technique on total weight loss (TWL) and gastro-esophageal reflux disease (GERD).MethodsObservational cohort study based on data from the national registries for bariatric surgery in the Netherlands, Norway, and Sweden. A retrospective analysis of prospectively obtained data from surgeries during 2015–2017 was performed based on 2-year follow-up. GERD was defined as continuous use of acid-reducing medication. The relationship between TWL, de novo GERD and operation technical variables were analyzed with regression methods.ResultsA total of 5927 patients were included. The average TWL was 25.6% in Sweden, 28.6% in the Netherlands, and 30.6% in Norway (p < 0.001 pairwise). Bougie size, distance from the resection line to the pylorus and the angle of His differed between hospitals. A minimized sleeve increased the expected total weight loss by 5–10 percentage points. Reducing the distance to the angle of His from 3 to just above 0 cm increased the risk of de novo GERD five-fold (from 3.5 to 17.8%).ConclusionSmaller bougie size, a shorter distance to pylorus and to the angle of His were all associated with greater weight loss, whereas a shorter distance to angle of His was associated with more de novo reflux.Graphical

Uniaxial mechanical stretch properties correlated with three-dimensional microstructure of human dermal skin.

The intact and healthy skin forms a barrier to the outside world and protects the body from mechanical impact. The skin is a complex structure with unique mechano-elastic properties. To better direct the design of biomimetic materials and induce skin regeneration in wounds with optimal outcome, more insight is required in how the mechano-elastic properties emerge from the skin's main constituents, collagen and elastin fibers. Here, we employed two-photon excited autofluorescence and second harmonic generation microscopy to characterize collagen and elastin fibers in 3D in 24 human dermis skin samples. Through uniaxial stretching experiments, we derive uni-directional mechanical properties from resultant stress-strain curves, including the initial Young's modulus, elastic Young's modulus, maximal stress, and maximal and mid-strain values. The stress-strain curves show a large variation, with an average Young's modules in the toe and linear regions of 0.1 MPa and 21 MPa. We performed a comprehensive analysis of the correlation between the key mechanical properties with age and with microstructural parameters, e.g., fiber density, thickness, and orientation. Age was found to correlate negatively with Young's modulus and collagen density. Moreover, real-time monitoring during uniaxial stretching allowed us to observe changes in collagen and elastin alignment. Elastin fibers aligned significantly in both the heel and linear regions, and the collagen bundles engaged and oriented mainly in the linear region. This research advances our understanding of skin biomechanics and yields input for future first principles full modeling of skin tissue.

Large variation in anti-factor Xa levels with nadroparin as thromboprophylaxis in COVID-19 and non-COVID-19 critically ill patients

PurposeCritically ill COVID-19 and non-COVID-19 patients receive thromboprophylaxis with the LMWH nadroparin. Whether a standard dosage is adequate in attaining the target anti-FXa levels (0.20–0.50 IU/ml) in these groups is unknown.MethodsThis study was a prospective, observational study in the ICU of a large general teaching hospital in the Netherlands. COVID-19 and non-COVID-19 patients admitted to the ICU who received LMWH in a prophylactic dosage of 2850 IU, 5700 IU or 11400 IU subcutaneously were eligible for the study. Anti-FXa levels were determined 4 h after administration. Relevant laboratory parameters, prespecified co-variates and clinical data were extracted from the electronic health record system. The primary goal was to evaluate anti-FXa levels in critically ill patients on a prophylactic dosage of nadroparin. The second goal was to investigate whether covariates had an influence on anti-FXa levels.ResultsA total of 62 patients were included in the analysis. In the COVID-19 group and non-COVID-19 group, 29 (96%) and 12 patients (38%) reached anti-FXa levels above 0.20 IU/ml, respectively. In the non-COVID-19 group, 63% of the patients had anti-FXA levels below the target range. When adjusted for nadroparin dosage a significant relation was found between body weight and the anti-FXa level (p = 0.013).ConclusionA standard nadroparin dosage of 2850 IU sc in the critically ill patient is not sufficient to attain target anti-FXa levels in the majority of the studied patient group. We suggest a standard higher dosage in combination with body-weight dependent dosing as it leads to better exposure to nadroparin.Clinical trials registrationRetrospectively registered, ClinicalTrials.gov ID NTC 05926518 g, date of registration 06/01/23, unique ID 2020/1725.

Effects of medical interventions on health-related quality of life in chronic disease - systematic review and meta-analysis of the 19 most common diagnoses.

The demographic shift leads to a tremendous increase in age-related diseases, which are often chronic. Therefore, a focus of chronic disease management should be set on the maintenance or even improvement of the patients' quality of life (QoL). One indicator to objectively measure QoL is the EQ-5D questionnaire, which was validated in a disease- and world region-specific manner. The aim of this study was to conduct a systematic literature review and meta-analysis on the QoL across the most frequent chronic diseases that utilized the EQ-5D and performed a disease-specific meta-analysis for treatment-dependent QoL improvement. The most common chronic disease in Germany were identified by their ICD-10 codes, followed by a systematic literature review of these ICD-10 codes and the EQ-5D index values. Finally, out of 10,016 independently -screened studies by two persons, 538 studies were included in the systematic review and 216 studies in the meta-analysis, respectively. We found significant medium to large effect sizes of treatment effects, i.e., effect size >0.5, in musculoskeletal conditions with the exception of fractures, for chronic depression and for stroke. The effect size did not differ significantly from zero for breast and lung cancer and were significantly negative for fractures. Our analysis showed a large variation between baseline and post-treatment scores on the EQ-5D health index, depending on the health condition. We found large gains in health-related quality of life mainly for interventions for musculoskeletal disease. https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42020150936, PROSPERO identifier CRD42020150936.

Population and Conservation Status of Bighorn Sheep in the State of Baja California, Mexico

The bighorn sheep in Mexico is classified as at-risk by the Mexican federal government. In the state of Baja California, wild sheep can be observed throughout the length of the state from the USA–Mexico border south to the Agua de Soda mountain range. This research aimed to document the historical trend of the bighorn population based on aerial surveys conducted in 1992, 1995, 1999, 2010, and 2021, and the abundance, distribution, and structure of bighorn sheep populations in Baja California, based on an aerial survey conducted from 8–14 November 2021, covering thirteen mountain ranges. The estimated sheep population in 2021 was based on the number of individuals observed; the sightability of the animals; the area sampled; and the total area of habitat available. In 30.5 flight hours, 456 bighorn sheep were observed, with an estimated population of 1697 ± 80 individuals. The observation rate was 16 sheep sighted per hour of flight, and the ram:ewe:lamb ratio was 62:100:19. When the results of the 2021 flight were compared to the results of the previous aerial surveys, there was a large variation between the data, which was related to the lack of consistency between the sampling designs used in each study. Nevertheless, a statistical test of the results of aerial surveys conducted in the state suggest that the Baja California bighorn sheep population remained stable between 1992 and 2021. This study highlights the need to standardize wild sheep aerial surveys by defining flight paths and establishing a consistent duration of flights. On the other hand, Baja California authorities should consider modifying the current conservation strategy for bighorn sheep to increase the species’ population in the state by initiating community-based wildlife conservation programs in rural communities.

A new approach to measure spatial variability of soil parameters and field technique to test-value specific fertilizer recommendations

&lt;p&gt;Information on the distribution of soil properties is important to know the status of nutrients in the soils based on which fertilizer nutrients are recommended. Given the variability of nutrients in the soils, making a site-specific fertilizer recommendation seems to be a compelling work. To determine the spatial variability of soil nutrients and to make judicious and precise fertilizer recommendations, new measures are designed with this study. These measures are tested against the soil samples (n = 43) for total nitrogen (N), organic matter (OM), phosphorus (P2O5), and potassium (K2O) in the study area. The descriptive statistical analysis indicated an average of low nitrogen and organic matter, while phosphorus was found to be very high and the level of potassium was high. The spread of nutrients across the data sets, however, included low, medium, high, and very high levels of ratings. The Deviation Square Index was developed and applied for the variability measurement and found that the largest variation was with phosphorus distribution, followed by potassium, nitrogen, and organic matter. The coefficient of variation (CV%) analysis also exhibited similar trends in nutrient distributions. Nitrogen was the main determinant explaining the variations in rice yield, while phosphorus and potash were negatively related to the yield. An index of fertilizer nutrient recommendation called Test-Value Specific Dose (TVSD) was developed and used to calculate the nutrient recommendation for each sampled location. This new method gave easy and more accurate doses of fertilizer over the blanket recommendation to fit the variations across the soil samples.&lt;/p&gt;

Facility-Level Variation in Racial Disparities in Anticoagulation for Atrial Fibrillation: The REACH-AF Study.

Oral anticoagulation reduces stroke risk for patients with atrial fibrillation (AF). Prior research demonstrates lower anticoagulant prescribing in Black than in White individuals but few studies have examined racial differences in facility-level anticoagulant prescribing for AF. To assess variation in anticoagulant initiation by race within Veterans Health Administration (VA) facilities. Retrospective cohort study. Black and White patients enrolled in the VA with incident AF from 2020 through 2021. The primary outcome was rate of any anticoagulant initiation (i.e., warfarin or direct oral anticoagulant [DOAC]) or any DOAC therapy within 90days of an AF diagnosis, overall and for Black and White patients at each facility. We also estimated the adjusted Black-White risk difference. In 82 VA facilities serving 26,832 Black and White patients, overall unadjusted rates of any anticoagulant therapy ranged from 56.8 to 87.1% across facilities; the corresponding ranges for Black and White patients were 47.6 to 91.3% and 58.2 to 87.1%, respectively. Overall unadjusted rates of DOAC therapy ranged from 55.1 to 85.5% by facility; ranges for Black and White patients were 42.8 to 86.9% and 56.4 to 85.5%, respectively. The adjusted risk difference between Black and White patients ranged from - 29.9 (95% CI, - 54.9 to - 4.8) to 14.2 (95% CI, - 9.1 to 25.0) across facilities for any anticoagulant therapy and from - 28.8 (95% CI, - 58.3 to 0.8) to 15.0 (95% CI, - 8.0 to 38.1) for DOAC therapy.For any anticoagulant therapy there were 3 facilities where prescribing was statistically higher in White than Black patients; for DOAC therapy there were 5 such facilities. In a national cohort of patients with AF, we observed large facility-level variation and adjusted risk differences in any anticoagulant and DOAC initiation, overall and by race. These findings represent a target for local quality improvement in AF care.

How do paediatric physical therapists teach motor skills to children with Developmental Coordination Disorder? An interview study.

When teaching motor skills, paediatric physical therapists (PPTs) use various motor learning strategies (MLSs), adapting these to suit the individual child and the task being practised. Knowledge about the clinical decision-making process of PPTs in choosing and adapting MLSs when treating children with Developmental Coordination Disorder (DCD) is currently lacking. Therefore, this qualitative study aimed to explore PPTs' use of MLSs when teaching motor skills to children with DCD. Semi-structured individual and group interviews were conducted with PPTs with a wide range of experience in treating children with DCD. A conventional content analysis approach was used where all transcripts were open-coded by two reviewers independently. Categories and themes were discussed within the research group. Data were collected until saturation was reached. Twenty-six PPTs (median age: 49 years; range: 26-66) participated in 12 individual interviews and two focus-group interviews. Six themes were identified: (1) PPTs treated children in a tailor-made way; (2) PPTs' teaching style was either more indirect or direct; (3) PPTs used various strategies to improve children's motivation; (4) PPTs had reached the optimal level of practice when children were challenged; (5) PPTs gave special attention to automatization and transfer during treatment; and (6) PPTs considered task complexity when choosing MLSs, which appeared determined by task constraints, environmental demands, child and therapist characteristics. PPTs' clinical decision-making processes in choosing MLSs appeared strongly influenced by therapist characteristics like knowledge and experience, resulting in large variation in the use of MLSs and teaching styles to enhance motivation, automatization, and transfer. This study indicates the importance of the level of education on using MLSs to teach children motor skills, and clinical decision-making. Future research should focus on implementing this knowledge into daily practice.

WITHDRAWN: Insights into the source contributions to the elevated fine particulate matter in Nigeria using a source-oriented chemical transport model

In 2021, Nigeria was ranked by the World Health Organization (WHO) as one of the top countries with highly deteriorating air quality in the world. To date, no study has elucidated the sources of elevated fine particulate matter (PM2.5) concentrations over the entire Nigeria. In this study, the Community Multiscale Air Quality (CMAQ) model was applied to quantify the contributions of seven emissions sectors to PM2.5 and its components in Nigeria in 2021. Residential, industry, and agriculture were the major sources of primary PM (PPM) during the four seasons, elemental carbon (EC) and primary organic carbon (POC) were dominated by residential and industry, while residential, industry, transportation, and agriculture were the important sources of secondary inorganic aerosols (SIA) and its components in most regions. PM2.5 was up to 150 μg/m3 in the north in all the seasons, while it reached ∼80 μg/m3 in the south in January. Residential contributed most to PM2.5 (∼80 μg/m3), followed by industry (∼40 μg/m3), transportation (∼20 μg/m3), and agriculture (∼15 μg/m3). The large variation in the sources of PM2.5 and its components across Nigeria suggests that emissions control strategies should be separately designed for different regions. The results imply that urgent control of PM2.5 pollution in Nigeria is highly necessitated.

Forest demography and biomass accumulation rates are associated with transient mean tree size vs. density scaling relations.

Linking individual and stand-level dynamics during forest development reveals a scaling relationship between mean tree size and tree density in forest stands, which integrates forest structure and function. However, the nature of this so-called scaling law and its variation across broad spatial scales remain unquantified, and its linkage with forest demographic processes and carbon dynamics remains elusive. In this study, we develop a theoretical framework and compile a broad-scale dataset of long-term sample forest stands (n = 1,433) from largely undisturbed forests to examine the association of temporal mean tree size vs. density scaling trajectories (slopes) with biomass accumulation rates and the sensitivity of scaling slopes to environmental and demographic drivers. The results empirically demonstrate a large variation of scaling slopes, ranging from -4 to -0.2, across forest stands in tropical, temperate, and boreal forest biomes. Steeper scaling slopes are associated with higher rates of biomass accumulation, resulting from a lower offset of forest growth by biomass loss from mortality. In North America, scaling slopes are positively correlated with forest stand age and rainfall seasonality, thus suggesting a higher rate of biomass accumulation in younger forests with lower rainfall seasonality. These results demonstrate the strong association of the transient mean tree size vs. density scaling trajectories with forest demography and biomass accumulation rates, thus highlighting the potential of leveraging forest structure properties to predict forest demography, carbon fluxes, and dynamics at broad spatial scales.

Analysis of discharge events in the CMS GE1/1 GEMdetectors in presence of LHC beam

In July 2022, the experiments installed on the Large Hadron Collider (LHC) accelerator ring started a new data taking phase, Run-3. Before this period, an upgrade campaign took place during the so called Long Shutdown 2 (2018–2022). In particular, the muon system of the CMS experiment has been upgraded with the installation of a new gas detector station, GE1/1, based on Gas Electron Multiplier technology (GEM). The CMS experiment has scheduled the installation of two additional GEM stations: GE2/1 and ME0. The aim of the GEM stations is to maintain the performance of the muon system, reached during the last data taking phase (Run-2), with the increase of instantaneous luminosity expected at the LHC. The installed GE1/1 station covers the pseudorapidity region 1.55 <|η|< 2.18. GE1/1 participated in the CMS Run-3 data taking from July to November 2022 and, in this period, its detectors were exposed for the first time to the radiation produced during the collisions of the LHC beams, with a center of mass energy of 13.6 TeV. Since the first days of Run-3, where only a few bunches collided in CMS, the GE1/1 detectors started to experience a significant number of discharges, affecting their smooth operation during the data taking. In this talk, we present an analysis of discharges, which started by simply counting the number of discharges occurring per detector. An interesting phenomenon observed was that the discharge rate can vary a lot among the installed detectors; this is due to the fact that the occurrence of discharges is driven by the manufacturing of the GEM foils used in the detectors. Imperfections in their manufacturing can lead to large variation in the discharge rate. In addition, the rate can vary in time, due to the fact that discharges can produce damage at the site generating them, deactivating a particular hole or, in the worst case, producing a short circuit in the GEM foil, deactivating a part of the foil amplification region. We present the evolution of the discharge rate in time and its dependence on the HV working point and on the luminosity delivered by the LHC beams. This contribution illustrates the actions taken to mitigate the discharge rate and to assure a smooth detector operation.

Development and Validation of an Efficient and Safe Loud Music Exposure Paradigm.

The purpose of this study was to develop a time-efficient music exposure and testing paradigm that safely creates temporary cochlear dysfunction that could be used in future temporary threshold shift (TTS) studies. A 30-min audio compilation of pop rock music tracks was created. Adult volunteers with normal hearing were then exposed to this music material monaurally through headphones for 30 min at 97 dBA or 15 min at 100 dBA. Levels were measured from the ear of a manikin and are considered to provide an equivalent daily noise dose based on a 3-dB exchange. We assessed the changes in their hearing, by means of distortion product otoacoustic emission (DPOAE) testing, and standard and extended high-frequency pure-tone audiometry before and after exposure. There were 17 volunteers in total. In the first trial, eight volunteers (four females; Mdnage = 31 years [interquartile range, IQR = 4.25]) were included. Although TTS was observed in all eight participants for at least one frequency, a large variation in affected frequencies was observed. To address this issue, the audio material was further remastered to adjust levels across the different frequency bands. Fourteen adults (nine newly recruited and five from the first trial; seven females; Mdnage = 31 years [IQR = 5]) were exposed to the new material. All but two of 17 participants presented clinically significant TTS or decrease in DPOAE amplitude in at least one frequency. Statistically significant average TTS of 7.43 dB was observed at 6 kHz. There were statistically significant average DPOAE amplitude shifts of -2.55 dB at 4 kHz, -4.97 dB at 6 kHz, and -3.14 dB at 8 kHz. No participant presented permanent threshold shift. A monaural music paradigm was developed and shown to induce statistically significant TTS and DPOAE amplitude shifts, without evidence of permanent loss. This realistic and time-efficient paradigm may be considered a viable option for experimental studies of temporary music-induced hearing loss. https://doi.org/10.23641/asha.25016471.