Group Size Research Articles

Seeing the Futures: Evaluating the Application of Structured Analytic Technique Alternative Futures Analysis

The Structured Analytic Technique (SAT) Alternative Futures Analysis (AFA) is an imaginative thinking technique used by intelligence analysts in circumstances of uncertainty to generate and explore a range of potential future states. Recent literature on SATs has been critical of their use because of an absence of robust evidence of their value. This research observed focus groups which applied AFA to a specific case study and evaluated their outputs. The results suggest AFA can be used less prescriptively than some of the literature sets out in terms of group size and timeframe, while also supporting the recommended use of a facilitator. An understanding of the purpose of AFA as an imaginative thinking technique, intended to explore future possibilities, is vital in applying the technique, evaluating it, and communicating the results. The potential for mismatch between the criteria suggested to analyse SATs in general and the intent of AFA as a technique, undervalues the technique. A key consideration in evaluating AFA, is the need to ensure the technique is applied as intended. Further, this research identifies that the learning context may influence the application of AFA.

The application of interventional methods in control of blood loss during giant upper extremity tumor resection

BackgroundThe purposes of this retrospective study were to determine the efficacy of interventional methods in control of intraoperative blood losses and investigate the perioperative complications.MethodsThe cases of 44 patients in whom a giant upper extremity tumor had been operated between 2008 and 2022 were analyzed retrospectively. Of these, 29 patients were treated with interventional methods (Group A) and 15 were treated without (Group B). Group A was further divided based on the intervention methodss: Group C (combination of balloon occlusion and transarterial embolization [TAE], n = 11) and Group D (single TAE, n = 18). Within Group D, patients were categorized based on the timing of TAE relative to surgery into Group E (TAE on the same day as surgery) and Group F (TAE performed days before surgery). We compared demographic features, blood loss, ICU admission rates, and use of vasopressors during surgery.ResultsWe collected clinical records from 44 patients diagnosed with a giant upper extremity tumor who underwent surgery. Group sizes were as follows: A (29), B (15), C (11), D (18), E (7), and F (11). Tumor volumes in the interventional and non-interventional groups were similar (704.19 ± 812.77 cm³ vs. 1224.53 ± 1414.01 cm³, P = 0.127). Blood plasma transfusion was significantly higher in Group B compared to Group A (425.33 ± 476.20 ml vs. 155.90 ± 269.67 ml, P = 0.021). Although overall blood loss did not significantly differ between Group A and Group B (467.93 ± 302.08 ml vs. 1150 ± 1424.15 ml, P = 0.087), the rate of massive bleeding (defined as blood loss over 1000 ml) was lower in Group A (6.9% vs. 46.47%, P = 0.004). The proportion of minors (patients aged less than 18) in Group C was significantly higher than in Group D (27.7% vs. 0.00%, P = 0.045). The amount of RBC transfusion was also significantly higher in Group C compared to Group D (458.18 ± 292.22 ml vs. 164.44 ± 224.03 ml, P = 0.021). No significant perioperative complications were observed.ConclusionsInterventional techniques have been shown to reduce both blood loss and the necessity for blood transfusions in patients with large upper extremity tumors. Furthermore, no significant perioperative complications have been observed.

Parrots live in smaller groups on islands.

Species living on islands are predictably different from their mainland counterparts in morphology and behaviour, but the source of these differences is still debated. Islands, in particular, are characterized by depauperate predator communities. Relaxed predation pressure might explain why living in groups, a common anti-predator adaptation in animals, is considered less likely on islands. However, the empirical evidence for this effect is scant and alternative explanations have been overlooked. For instance, smaller groups might be more common because island species are less studied, because a more stable food supply associated with benign climate on islands favours territoriality, or because the population density is too low to allow the formation of larger groups. I examined the determinants of foraging group size in parrots, a large worldwide avian order with many island populations. Using a multivariable phylogenetic framework, I found that foraging group size was smaller on islands than on the continents controlling for ecological variables known to influence group size such as diet and body size. In addition, the island effect persisted after controlling for research effort, climate variables and population density, suggesting that impoverished predator communities are an important driver of group size on islands.

Analysis of pedestrian crossing violations at an overpass location by using a logit model

Jaywalking significantly increases accident risks compared to marked crosswalks. Overpasses are often installed to address this, but violations continue. This study examines pedestrian behavior at overpass locations, focusing on 438 individuals recorded on video. Factors like parked vehicles, gender, age, group size, mobile phone distraction, carrying items, the number of waiting pedestrians upon arrival, waiting times, and traffic volume were analyzed. Since jaywalking is more frequent during off-peak hours when traffic is not congested, observations were made at random intervals during these times. A binary logit model was used to identify the factors influencing jaywalking. The study found that points of interest near overpasses significantly affect pedestrian behavior. Additionally, parked vehicles near the overpass reduce crossing distance, encouraging jaywalking. Policy recommendations include implementing parking restrictions and strategically locating overpasses to align with pedestrian movement patterns and nearby points of interest.

A metal–organic frameworks-imprinted emulsion interface with dynamic size- and site-selective recognition for significantly enhanced flavoniods extraction

The boronic acid suspended Cr based MIL-100 (MIL-100-B) sorbents have been widely used to separation of cis-diol containing molecules. However, it’s still challenging in fabrication of high performance metal organic frameworks (MOFs) due to its irregular size and low content of functional groups. For improving identification efficiency, the emulsion microreactor were firstly designed to purify MIL-100-B prior to their use. Herein, a highly ordered MOFs-imprinted polymer microsphere was synthesized by O/W Pickering emulsion template, which can highly selective separation of MIL-100-B via the synergistic effect of boronic acid sites and imprinted cavities. The obtained purified H-MIL-100-B exhibited the uniform size and abundant boronic acid groups (B elements ratio up to 27.37 %). The emulsion imprinted microsphere (EIMs) showed the good selectivity towards MIL-100-B. Additionally, the obtained MOF-imprinted microsphere exhibited green, convenient, sustainable separation process towards the purification and recycle of MIL-100-B. The purified MOFs (H-MIL-100-B) were used to specific bind with cis-diol flavoniods naringin (NRG). Satisfactorily, H-MIL-100-B show high adsorption amount (43.69μmol/g at 308 K), fast capture kinetics (160 min), high selectivity and excellent regenerability (up to seven cycles). Remarkably, the purified NRG solutions displayed lasting antibacterial activity against Staphylococcus aureus (S. aureus) with inhibition zone of 13.47 mm. More importantly, the H-MIL-100-B could effectively promote the specific recognition ability of NRG by reducing matrix interference and improving purification efficiency (93.93 %) from complex natural extracts. A high score (0.75) was predicted via analytical GREEnness (AGREE) approaches, demonstrating environmentally friendly and greenness of separation process. The MOFs-imprinted emulsion microspheres possessed dynamic recognition properties towards target MOFs, thus opening new direction for the development of convenient and efficient microreactor for the purification of other functional MOFs.

Long-term surgical outcomes of ileovesicostomy at a single children's hospital

IntroductionThe ileovesicostomy (IV) is a surgical option for patients with refractory bladder dysfunction at-risk of upper tract deterioration who cannot catheterize or lack social support for managing an augmentation cystoplasty (AC). Long-term outcomes after IV in children are lacking in the literature. ObjectiveWe assessed the risk of long-term surgical complications in pediatric patients with IV at a single children’s hospital. Study designWe retrospectively reviewed the records of patients undergoing IV between 2002 to 2021 at a single children’s hospital. The primary outcome was the rate of surgical complications in IV patients after initial reconstruction. Specific complications of interest included intra-abdominal, reservoir, and stomal complications, respectively. We also assessed renal outcomes, including the change in glomerular filtration rate (ΔGFR) and Society of Fetal Urology (ΔSFU) hydronephrosis from the time of surgery to last follow up. ResultsThe study comprised 17 IV patients, with most patients having a diagnosis of spina bifida (65%). Median follow-up was 6.4 years. The mean rate of surgical complications per patient year was 0.11 +/- 0.20. On survival analysis, the time to first complication for IV was 84.4 months. The incidence of intra-abdominal, reservoir, and stomal complications over the study period was 2/17 (11.8%) for each of these complication types. The mean ΔSFU grade from the time of surgery to last follow up was -1.24 +/- 1.48 and mean ΔGFR was -2.5 +/- 32.7 ml/min. DiscussionWe found that IV in pediatric patients experience a low rate (0.11/year) of complications and that median time to first complication was 84 months. Additionally, IV offers adequate renal preservation. Our study is limited, though, by its retrospective nature, small sample size, heterogenous population and lack of comparison group. ConclusionOur experience demonstrates that IV has a low rate of surgical complications and preserves renal function. We believe it is a reasonable surgical option for the well selected patient with refractory bladder dysfunction at-risk of upper tract deterioration who is unable to reliably catheterize.

High-purity κ-carrageenan from Kappaphycus alvarezii algae for aerogel production by supercritical CO2 drying

Carrageenan, a polysaccharide mostly extracted from Kappaphycus alvarezii (KA), is valuable for cosmetic and food uses due to large quantities of κ-carrageenan. High-pressure sequential extractions can recover high-purity carrageenan from KA, adequate for aerogel production. The biopolymer properties such as size, shape, and sulphate groups affect the gel form and aerogel characteristics. In this work, aerogels were obtained by supercritical CO2 drying, and cryogels by freeze-drying, using high-purity carrageenan, recovered by sequential high-pressure extractions (HP), and commercial carrageenan (CC). The results indicated that HP samples showed higher volumetric shrinkage (96%), firmness (254N), and envelope density (0.008g.cm-3) compared to CC samples. Aerogels presented characteristics of pore volume, surface area, and density suggesting supercritical drying as feasible method to produce porous materials. Besides, the aerogels present valuable properties compared to cryogel, including high firmness, useful for applications in packages, scaffolds, or delivery systems, a tendency that must be increasingly explored.

Coordination failure in experimental banks of different sizes

We run a laboratory experiment to investigate how group size affects coordination in a bank-run game, in which participants choose simultaneously whether to withdraw or not and group members change over time. We find that bank size significantly affects the individual withdrawal probability, which is on average 12% higher in large than in small banks. In the initial round(s), all groups exhibit a similar withdrawal rate of about 40%; then, large and medium banks converge to the bank-run equilibrium, while small banks exhibit no systematic convergence. In all banks, experience and beliefs significantly affect the probability to withdraw and to experiment, i.e., to take in the current round the decision opposite to what was the best response in the previous one. We show that experimentation is a strategic choice, and interpret it as an attempt at promoting group convergence towards the efficient equilibrium.

A Meta-analysis of Horticultural Therapy Programs for Older Adults with Dementia

Background and objective: This study analyzed the effect size of each element to secure the expertise of horticultural therapy programs for older adults with dementia.Methods: This study conducted a meta-analysis to analyze the effectiveness of horticultural therapy programs for older adults with dementia using 'horticulture' as a search term. To this end, 29 articles were selected and analyzed from a total of 147 articles published between 2003 and 2022.Results: First, the overall effect size of horticultural therapy for older adults with dementia was .522, which is statistically significant. This is considered a medium effect size according to Cohen's (1988) criteria for effect size. Second, the group size, a variable related to the number of subjects, showed the largest effect size when the group had 21–30 participants, and the number of sessions per week showed the largest effect size when the number of sessions was once a week, followed by twice a week, and so on. The effect size was largest when the total number of sessions was 21 or more, and when each session was conducted for 90-120 minutes.Conclusion: This study examined previous studies related to horticultural therapy programs for older adults with dementia through a meta-analysis and presented the results of a systematic effect size analysis. The significance of this study is that it summarized the factors that have a large effect and quantified the effect sizes so that it can be used in various horticultural therapy programs for older adults with dementia.

Wild pear (Pyrus pyraster (L.) Burgsd.) fruit and seed morphology depending on fruit size

The current study aims to evaluate the effects of fruit size of wild pear (Pyrus pyraster (L.) Burgsd.) on morphological fruit and seed traits. Wild pear fruit was collected from 10 trees in the area of Žumberačko gorje in the fall of 2022. The fruit was randomly collected from the ground and divided into three groups according to their weight (small (<10 g), medium (10 – 15 g) and large (>15 g)). Fruit size had a significant effect on the following morphological traits: fruit weight, fruit length, fruit width, the number of filled seeds, the weight of fresh seeds per fruit, the weight of 1 fresh seed and the weight of air-died seed, while no significant difference was found for fruit shape index, the number of empty seeds, the weight of 1 air dried seed and the share of seed dry matter. For all the aforementioned traits where the difference was significant, large fruit had significantly highest values, while in most cases (with the exception of the weight of 1 fresh seed), medium fruit had significantly higher values than small fruit. Comparing the correlation coefficients between different fruit size groups, it is evident that higher fruit size traits had a significant effect on the number of filled seeds in medium and large wild pear fruit only. In addition, it is visible that fruit weight and width, and not fruit length, had of the largest impact on the number of filled seeds. The principal component analysis revealed 3 significant principal components with eigenvalues greater than 1, which explained 75.88% of the total variability. It was shown that large fruit distinguish themselves from small and partly between medium by F1 axis. F1 was mainly influenced by fruit weight, fruit length, fruit width, the number of filled seeds, the weight of fresh seeds per fruit and the weight of air-dried seed per fruit. Based on the results obtained from this study, it can be concluded that for nursery production of wild pear seedlings bigger fruit should be used due to the higher number of filled seeds.

Exploring C2 and N6 Substituent Effects on Truncated 4'-Thioadenosine Derivatives as Dual A2A and A3 Adenosine Receptor Ligands.

Based on high binding affinity of truncated 2-hexynyl-4'-thioadenosine (3a) at both A2A adenosine receptor (AR) and A3 AR, we explored structure-activity relationship (SAR) of the C2-substitution by altering chain length of the 2-hexynyl moiety, thereby evaluating the hydrophobic pocket size. A series of truncated N6-substituted 4'-thioadenosine derivatives with C2-alkynyl substitution were successfully synthesized from D-mannose, using a palladium-catalyzed Sonogashira coupling reaction as the key step, whose structures were confirmed by the X-ray crystal structure of 4h. As the size of the alkynyl group at the C2-position increased, the binding affinity improved; however, when the substituted group was larger than hexynyl, the binding affinity decreased. The introduction of a bulky hydrophobic group such as 3-halobenzyl group at the free N6-amino group decreased the binding affinity at hA2AAR. These results confirm our previous findings that a free amino group at N6-position and longer hydrophobic chain at C2-position are essential for hA2A AR binding affinity. The introduction of a bulky hydrophobic group at free N6-amino group maintained the binding affinity at hA3 AR. The binding mode of truncated 2-substituted-4'-thioadenosine derivatives to hA2A and hA3 AR were predicted by a molecular docking study.

Symmetries of Fano varieties

Abstract Prokhorov and Shramov proved that the BAB conjecture, which Birkar later proved, implies the uniform Jordan property for automorphism groups of complex Fano varieties of fixed dimension. This property in particular gives an upper bound on the size of finite semi-simple groups (i.e., those with no nontrivial normal abelian subgroups) acting faithfully on 𝑛-dimensional complex Fano varieties, and this bound only depends on 𝑛. We investigate the geometric consequences of an action by a certain semi-simple group: the symmetric group. We give an effective upper bound for the maximal symmetric group action on an 𝑛-dimensional Fano variety. For certain classes of varieties – toric varieties and Fano weighted complete intersections – we obtain optimal upper bounds. Finally, we draw a connection between large symmetric actions and boundedness of varieties, by showing that the maximally symmetric Fano fourfolds form a bounded family. Along the way, we also show analogues of some of our results for Calabi–Yau varieties and log terminal singularities.

Open Reduction and Internal Fixation Is a Feasible Alternative to Femoral Revision Arthroplasty in Geriatric Patients with Vancouver B2/3 Type Periprosthetic Fractures: A Study Analyzing In-Hospital Outcomes.

Purpose: The surgical management of periprosthetic femoral fractures is particularly challenging in geriatric patients due to physiological limitations. The choice between open reduction and internal fixation (ORIF) and hip revision arthroplasty for treating Vancouver B2 and B3 fractures remains controversial. This study aims to contribute further evidence by analyzing the in-hospital outcomes in geriatric patients with Vancouver B2/3 fractures. Methods: This retrospective study analyzed 133 patients treated for Vancouver B2/3 fractures at a level I trauma center from 2017 to 2023. Data were collected on preclinical characteristics, comorbidities, Vancouver classification, surgery-related parameters, and postoperative outcomes for an age- and gender-matched analysis. A subgroup analysis was also conducted on patients classified as American Society of Anesthesiologists (ASA) class 3 and 4. Results: Among the 133 patients, 85 suffered Vancouver B2 fractures and 48 Vancouver B3 fractures. Age-and-gender-matched analysis revealed that ORIF was more commonly performed in patients with higher ASA grades. A subgroup analysis of ASA 3 and 4 patients and an age-and-gender-matched analysis showed that ORIF resulted in shorter operation times and less blood loss. No significant differences were found in mortality or complication rates. Conclusions: ORIF is associated with shorter operation times, less bleeding, and comparable in-hospital outcomes in treating Vancouver B2/3 fractures in higher-risk geriatric patients compared to revision arthroplasty. The retrospective design and small sample size in the ORIF group are limitations of the study. Further studies with functional evaluation are still required.

A Moving Target: Studying the Effect of Continuous Transcutaneous CO2 Monitoring in ELBW Infants During an Equipoise Shift.

Objectives: To assess whether continuous non-invasive pCO2 monitoring by transcutaneous pCO2 monitor (TCpCO2) among extremely low birth weight (ELBW) premature infants, during the first week of life, will decrease the rate of high-grade intraventricular hemorrhage (IVH) or periventricular leukomalacia (PVL) or the combined outcome of IVH/PVL and death. Methods: This was a prospective, observational, multicenter study. Due to ethical constraints, allocation was based on TCpCO2 monitor availability. ELBW infants were either monitored by TCpCO2 monitor (Sentec, Therwil, Switzerland) (study group), or recruited to the control group if a TCpCO2 monitor was not available. Results: A total of 132 ELBW infants participated in the study. The size of the study group (106 infants) and the control group (26 infants) differed because monitor availability increased during the study period reflecting change in standard of care. The groups had comparable gestational age and baseline characteristics. No difference was found in the rate of IVH/PVL in the study vs. control groups (10% vs. 4%; p = 0.7, respectively), or in the combined outcome of PVL/IVH and death (16% vs. 15%; p = 1.0, respectively). Conclusions: This study demonstrates the challenges in conducting a prospective controlled trial in a rapidly evolving medical field. While the study began with a clear equipoise, this balance shifted as the care team gained more experience with TCpCO2 monitoring among the study population, despite the absence of new clinical evidence to justify such a shift. Consequently, the small control group limited our ability to draw definitive conclusions regarding the study's objective. However, our findings may increase awareness of continuous non-invasive pCO2 monitoring in extremely premature infants.

A prediction model of PTSD in the Israeli population in the aftermath of october 7th, 2023, terrorist attack and the Israel–Hamas war

BackgroundOn October 7th, 2023, a mass terror attack was launched by Hamas militants, which was followed by the Israel-Hamas war. These events constitute a nationwide trauma with major ramifications for public mental health. This article presents an evidence-based model for the prediction of the prevalence of posttraumatic stress disorder (PTSD) related to the terrorist attack and the war.Main body: The creation of the model consisted of several steps. Firstly, the Israeli population was divided into six groups based on the intensity, context, and type of traumatic exposure (direct exposure to terror, close proximity to terror, soldiers in combat and support units, intense exposure to rocket attacks, moderate exposure to rocket attacks, and indirectly affected communities), and the population size of each group was assessed using official national databases. Secondly, an estimation of the expected prevalence of PTSD in each of the exposure groups was based on a review of the relevant literature. A random-effects meta-analysis of the prevalence rates was conducted separately per each exposure group. Finally, the predicted number of PTSD causalities in the population was calculated by multiplying the group size and the PTSD prevalence estimation. Based on population size and estimated PTSD prevalence within each exposure category, the model predicts that approximately 5.3% (N = 519,923) of the Israeli population (95% confidence interval, 1.64–9%), may develop PTSD as a result of the terrorist attack and the war.ConclusionsThe predicted number of individuals with PTSD following mass trauma is expected to be considerable. The presented model can assist policymakers, clinicians, and researchers in preparing and devising adequate interventions for the mental health needs of large populations. Moreover, this model can be applied in other instances of mass-trauma exposure.

Impact of Climate Deviation on Reproductive Profile of Nile Tilapia, Oreochromis niloticus (Linnaeus, 1758) from the Tons River, India

Nile tilapia, Oreochromis niloticus is among the leading farmed species around the world as well as a powerful invader in many countries globally. Studies were undertaken during the period from February 2019 to January 2020 from the lower stretch of the Tons River at Prayagraj, Uttar Pradesh, India. During the sampling period, 683 fish specimens of Nile Tilapia, Oreochromis niloticus (336 males and 347 females) were collected and studied for evaluation of sex ratio and sex structure. The sex ratios of male and female fishes were very close and reported 1.0:1.03 in the stock. The male ratio was higher in the small size group of fish with 81 to 200 mm size groups and 411 to 470 mm size group. The sex structure of males and females was observed at 49.19% and 50.81%, respectively in the case of stock. The female proportion was recorded as a minimum with 37.50% in the 441-470 cm size group and highest with 54.84% in the 381-410 mm size group. However, the male proportion was reported lowest at 45.16% in the 381-410 mm size group and highest at 62.50% in the 441-470 mm size group. In the present findings, O. niloticus was found to reach maturity starting below 138 mm of total length, taking individual fish. The fishes breed in the months of March to June and September to November of the year. The number of eggs per individual ranged from 393 to 4338 in the size of fish varied from 138-452 mm. The reported fecundity and sex ratio of O. niloticus indicated that the climatic condition or environmental condition of the Tons River was most suitable. The environmental condition (especially temperature) of the Tons River at Prayagraj is slightly warm compared to the Ganga River which is very favourable for O. niloticus. The water current velocity of the Tons River is very poor. Both parameters are very helpful for the stability of O. niloticus in the Tons River at Prayagraj. The high fecundity of O. niloticus in the Tons River at Prayagraj could probably be a result of a combination of different causes such as climatic conditions, habitat structure, food abundance, water quality, and quality of food. Therefore, the present study aimed to update the information on the sex ratio, sex structure, and fecundity of O. niloticus with respect to climate from the Tons River, India.

Estimated lifetime impact of a school-based intervention for mental health: A microsimulation study

Abstract Background The prevalence of childhood mental health problems is increasing. School-based interventions have the potential to reduce poor mental health and mental health inequalities. Our aim was to estimate the long-term costs and benefits of the Incredible Years Teacher® Classroom Management (IY-TCM) intervention in primary schools compared to no intervention. Methods LifeSim, an existing microsimulation model, was used to estimate the lifetime costs and benefits of IY-TCM by linking short-term changes in SDQ based on a previous trial in primary schools (Cluster RCT: 2075 children aged 4-9 years with a 30-month follow-up) to long-term health, social, economic and wellbeing outcomes. Benefits were measured in quality adjusted life years and wellbeing adjusted life years. We examined subgroup based on deprivation, conduct scores and parental depression. Results Microsimulation modelling estimated small gains in lifetime outcomes including reduced conduct disorder in adolescence and depression in adulthood. Estimates indicate IY-TCM could be cost-effective with a large amount of uncertainty (Net monetary benefit (NMB)=£21, Estimated CI = -£195, £240). IY-TCM was estimated to be more cost-effective for those with high deprivation (NMB = £231, Estimation CI - -£99, £231) and high conduct problem scores (NMB=£315, Estimated CI = £45, £483). Total net social benefit for a typical year size group was estimated to be £111m. Conclusions IY-TCM could be cost-effective compared to no intervention with a large estimated social benefit supporting wider implementation of IY-TCM, but results indicate a large amount of uncertainty. Greater benefits and higher certainty of cost-effectiveness for children with conduct problems and those living in a deprived area suggest IY-TCM has the potential to reduce mental health inequalities and may be more cost-effective for schools with higher deprivation and/or a high prevalence of conduct problems. Key messages • The Incredible Years Teacher Classroom Management intervention for mental health in primary schools could be considered cost-effective but there is a large amount of uncertainty. • Greater benefits for children with conduct problems and those living in a deprived area indicates the intervention has the potential to reduce mental health inequalities.

A novel viscosity sensitive hemicyanine fluorescent dye for real-time imaging of amyloid-β aggregation

Alzheimer's Disease (AD) is a neurodegenerative disease, of which β-amyloid (Aβ) deposition is one of the most important pathological features. It has been reported that during Aβ aggregation, the microenvironment around the Aβ protein is altered in terms of viscosity and polarity. In this work, we developed five novel hemicyanine fluorescent probes (MZs). After screening the photochemical properties, MZ-2 and 3 were found to enable the rapid detection of Aβ42 aggregates, which were also sensitive to ambient viscosity. After comparison the structure of probes, we also observed that extensions of conjugated π-systems effectively cause redshifts of excitation wavelength. In the meanwhile, hydroxyl groups with weaker ionization strengths are more responsive to Aβ42 aggregates than sulfonate groups, probably due to the small size of the hydroxyl group and the acidity. Overall, MZ-2 showed the best response to Aβ42 aggregates (15.35-fold) and viscosity (17.6-fold). MZ-2 can quickly cross the blood-brain barrier (BBB), enabling high-fidelity imaging of Aβ42 aggregates in the mice brain.

Identification of genetic variants associated with exercise-induced atrial fibrillation in high-performing racehorses

Abstract Background Atrial fibrillation (AF) is the most common cardiac arrhythmia in athletes. Despite a lower burden of classical cardiovascular risk factors, the prevalence of AF in athletes is comparable to that in the general population of similar age (~13%, mean age 65.5), suggesting that exercise-induced AF may have different underlying mechanisms. The prevalence of AF in thoroughbred (TB) and standardbred (STB) racehorses is also relatively high (~5%), suggesting exercise as an independent risk factor. Due to selective breeding and complete control of pedigrees, racehorses are well-suited for genetic studies. Common and rare genetic variation explain a substantial part of AF variance, but no study has identified genetic variants associated with exercise-induced AF in any species. Objective In this project, we aimed to use the racehorse as a model to identify genetic variants associated with exercise-induced AF, and in a future study, possibly replicate the results in human athletes. Here we present preliminary results from the genome-wide association study (GWAS) of AF in racehorses. Methods We collected blood or hair samples from 181 STB and TB racehorses in which 71 had paroxysmal or persistent AF verified by ECG. We extracted DNA and performed whole-genome genotyping using a commercial equine genotyping platform (670k markers). We phased and imputed un-genotyped markers and increased the sample size of the control group, using publicly available equine data from similar breeds from the European Nucleotide Archive. We conducted a GWAS of 7.85 million markers in 71 cases and 296 controls using PLINK2 with covariates adjusted for population stratification, batch and sex. Results We identified one significant locus downstream of the protocadherin gene PCDH18 associated with AF in racehorses. The same locus has been associated with the ECG-trait P-wave terminal force in humans. Changes in P-wave terminal force is associated with increased atrial size, delayed interatrial conduction, left ventricular fibrosis and left atrial function, and considered a good predictor of AF occurrence. Several non-significant but interesting signals were also identified including the genes SLC6A15 (amino acid transport), MYBPH (myosin binding), MYF6 and MYOG (myoblast differentiation). Conclusion In these preliminary results, we have identified a new genetic locus associated with AF in racehorses. In addition, we have identified several candidate genes for further studies to elucidate the genetic background of exercise-induced AF. We aim to replicate our findings in a population of human athletes. Our results may aid the development of risk prediction tools for exercise-induced AF and new drugs for tailored treatment of AF in general.

Peak atrial longitudinal strain to replace atrial volume in diastolic function grading: associations with long-term outcomes in a community-based sample with normal left ventricular ejection fraction

Abstract Background Diastolic dysfunction (DD) often precedes symptomatic heart failure and is a predictor of adverse outcomes; thus, accurate assessment and grading are crucial for early interventions. Current guidelines recommend combining multiple echocardiographic parameters, including left atrial volume index (LAVi), for diagnosing DD in patients with normal left ventricular ejection fraction (LVEF). Recently, peak atrial longitudinal strain (PALS) emerged as a more sensitive marker of left atrial function, although its added value in the grading of DD and associated adverse outcomes is scarcely explored. Purpose We aimed to investigate the impact of replacing LAVi with PALS on DD grading by its associations with long-term all-cause mortality in a low-risk, community-based sample. Methods We retrospectively identified 1319 volunteers from a population-based screening program (mean age 53.8±14.9 years, 59.1% female) with LVEF>50%. Subjects underwent echocardiography to measure mitral annular early diastolic velocities (e’), the ratio between mitral inflow early diastolic velocity (E) and e' (E/e'), tricuspid regurgitation peak velocity, LAVi, and PALS by speckle tracking. Diastolic function was initially classified according to the 2016 ASE/EACVI guidelines into normal, indeterminate, and DD groups and then reclassified by replacing LAVi>34 ml/m² with a standard PALS cut-off of <24%. The primary endpoint was all-cause mortality. Results During the median follow-up time of 11 years, 135 (10,2%) subjects met the primary endpoint. According to guideline definitions, 59 subjects were diagnosed with DD, 128 were indeterminate, and 1132 showed normal function. Kaplan-Meier analysis (Figure 1) showed significant differences in mortality between normal versus indeterminate and DD groups (log-rank p<0.001), with a three-fold (HR [95% CI]: 3.363 [1.802 - 6.274], and nearly five-fold increased risk (HR [95% CI]: 4.935 [1.919 - 12.690], respectively. Notably, no significant difference was observed between the outcomes of the indeterminate and DD groups. When subjects were reclassified using PALS instead of LAVi, 35 had DD, 75 were indeterminate, and 1209 had normal function. This classification resulted in different outcomes between groups (Figure 2, log-rank p=0.003). Compared to the normal, the indeterminate group exhibited a two-fold increase in mortality risk (HR: 2.277 [95% CI: 1.038-4.997]), while the DD group had a ten-fold increased risk (HR: 10.180 [95% CI: 2.870-36.130]). DD was associated with a nearly five-fold increase in mortality risk (HR: 4.724 [95% CI: 2.177-10.250]) compared to the indeterminate group. Conclusions In a community-based sample with normal LVEF, replacing LAVi with PALS in diastolic function classification separated groups with significant differences in their long-term all-cause mortality. This adjustment also reduced the size of the indeterminate group and refined its mortality risk.Figure 1Figure 2