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Maintaining biologically functional and compatible social groups is a primary welfare concern for captive animals. The aim of this study was to determine the effect of a pack size change -due to a new yearling- on the daily activity, use of space and inter-individual distance in a mated pair of Iberian wolves (Canis lupus signatus) housed at the Barcelona Zoo. Multifocal sampling methods were used for data collection, and instantaneous scans were made at 15-min intervals during 10-h sessions. 432 sampling points were balanced for the daily periods – morning, midday, and afternoon - for two different phases: dyad and triad phase. The subjects studied during the dyad phase - from April to May 1999 - were the mated pair. For the triad phase - from April to May 2000 – we studied the mated pair and the new yearling. When comparing these two study phases, there were statistically significant differences for the daily activity and the use of space. The mated pair used the space more homogenously during the triad phase. In the same phase, the inter-individual distance between the mated pair was statistically significantly closer in the morning and in the midday. The mated pair also showed individualized results for their daily activity, use of space and inter-individual proximity during the triad phase. Increasing understanding about the pack size enables the improvement of management to provide wolf packs with the most appropriate social environments.

Body size has a long history of study in paleobiology and underlies many important phenomena in macroevolution. Body-size patterns in the fossil record are often examined by utilizing size data alone, which hinders our ability to describe the biological meaning behind size change on macroevolutionary timescales. Without data reflecting the biological and geologic factors that drive size change, we cannot assess its mechanistic underpinnings. Existing frameworks for studying ontogeny and phylogeny can remedy this problem, particularly the classic age–size–"shape" space originally developed for studies of heterochrony. When evaluated based on metrics for age, size, and phenotype in populations, proposed mechanisms for size change can be outlined theoretically and tested empirically in the record. Using this framework, we can compare ontogenetic trajectories within and between species and determine how changes in size emerge. Here, we outline ontogenetic mechanisms for evolutionary size change, such as heterochrony, as well as how geologic factors can drive apparent, non-biological size change (e.g., taphonomic size sorting). To demonstrate the utility of this framework in actual paleobiological problems, we apply it to the Lilliput effect, a compelling and widely documented pattern of size decrease during extinction events. However, little is known about the mechanisms underlying this pattern. We provide a brief history of the Lilliput effect and refine its definition in a framework that can be mechanistically tested. Processes that likely produce Lilliput effects include allometric and sequence repatterning (including heterochrony) and evolutionary size-selective sorting. We describe these mechanisms and highlight relevant examples of the Lilliput effect for which feasible empirical tests are possible. [ABSTRACT FROM AUTHOR]

Clinical Relevance: Pupil size evaluation using clinical examination may be important for detecting and monitoring individuals at risk of neurotoxic effects from chemical exposure, as it may enable early intervention and the implementation of preventive measures., Background: This work aimed to investigate the association between pesticide exposure and pupil size. Pupil size is regulated by muscarinic and nicotinic receptors, and it is well-established that common pesticide chemicals disrupt this regulation., Methods: Twenty agricultural workers exposed to pesticides, and twenty participants not exposed, underwent visual screening, and pupil size evaluation under mesopic and photopic conditions. Additionally, signs of neurotoxicity and pesticide exposure in both groups were evaluated using the modified version of the neurotoxic symptoms questionnaire (Q16) and measuring cholinesterase (AChE) levels in blood, respectively., Results: Agricultural workers exposed to pesticides had a score indicating medium-high level of neurotoxicity (49.85 (SD ± 8.94)) which was significantly higher (t (36) = 7.659, p  ≤ 0.0001) than non-exposed participants who had low levels of neurotoxicity (27.25 SD ± 8.86). There was a significant difference in pupil size (mm) under mesopic (t (19) 4.42 p  = 0.003) and scotopic (t (19) 4.63, p  = 0.0002) conditions between the two groups. Additionally, there was a significant difference in AChE blood levels (t (19) 2.94 p  = 0.008) between exposed and non-exposed participants, indicating that exposed workers had low levels of this enzyme (average exposed group 3381 U/L (SD ± 1306)) compared to the non-exposed group (average non-exposed group 4765 U/L (SD ± 1300)). A significant negative correlation between AChE levels, years of exposure, and pupil size was found. The latter finding importantly showed that smaller pupils are associated with the accumulation of acetylcholine or a decrease in the activity of the enzyme AChE., Conclusion: Pupil size of agricultural workers exposed to pesticides can be abnormal and is associated with neurotoxicity as indicated by symptomatology and cholinesterase levels. Evaluation of pupil size may be useful for clinically detecting neurotoxicity.

Aim: To comprehensively examine the associations of childhood and adulthood body size, and child-to-adult body size change with adult leucocyte telomere length (LTL)., Methods: We included 453 602 participants from the UK Biobank. Childhood body size at the age of 10 years was collected through a questionnaire. Adulthood body size was assessed using body mass index (BMI), waist circumference (WC), waist-to-hip ratio (WHR), fat mass index (FMI), and fat-free mass index (FFMI)., Results: Individuals with plumper body size in childhood exhibited shorter LTL in adulthood (-0.0086 [-0.0017, -0.0004]). Adulthood BMI (-0.0286 [-0.0315, -0.0258]), WC (-0.0271 [-0.0303, -0.0238]), WHR (-0.0269 [-0.0308, -0.0230]) and FMI (-0.0396 [-0.0438, -0.0351]) were negatively associated with LTL, whereas FFMI (0.0095 [0.0039, 0.0152]) was positively associated with LTL. Compared to individuals consistently having an average/normal weight in both childhood and adulthood, those who maintained or developed overweight/obesity from childhood to adulthood had a shorter adult LTL, regardless of childhood body size. Notably, the LTL shortening effect was not observed in individuals with plumper body size in childhood but normal weight in adulthood., Conclusions: Childhood and adulthood obesity are both associated with LTL shortening in adulthood. Transitioning to or maintaining overweight/obese status from childhood to adulthood is associated with shorter adult LTL, whereas this effect can be reversed if plumper children become normal weight., (© 2024 John Wiley & Sons Ltd.)

Tropical cyclone (TC) has brought huge losses to coastal areas, whose intensity and size are both important indicators of destruction. The Northwest Pacific is the area with the most TCs generated. Due to the lack of effective observation methods and monitoring information, the TC operational centers of coastal countries or regions have not yet established complete TC outer-core size prediction and testing service. Thus, to select factors that significantly impact TC size changes and improve TC size forecast, statistical analysis is carried out on the climatological characteristics and the lifetime covariation characteristics of intensity and outer-core size (selected as the radius of damaging-force winds, R26) over the Northwest Pacific from July to November during 2004-2020, using the tropical cyclone best track data from JTWC (Joint Typhoon Warning Center) and SHIPS (Statistical Hurricane Intensity Prediction Scheme) reanalysis data. The results show that TC intensity and size peak in October, mainly showing a higher proportion of strong and large-sized TCs with longer lifetime at sea than in other months. Generally, the TC size expands with the increase in intensity and shrinks as the TC weakens. TCs reach the lifetime maximum size (LMS) later than the lifetime maximum intensity (LMI), with a mean lag time of 40 hours. Compared to the TC rapid intensification and LMI, the mean meridional positions of TC rapid expansion and LMS are closer to the coastal continent. Initial vortex size of TC affects the size development, especially LMS. Specifically, 58% of small initial vortices maintain the size in the small to medium category, while 71% of vortices with large initial size develop to large vortices in later periods, with 59% intensify to strong TCs (no less than 59 m·s-1) at LMI stage. Compared to small initial vortices, vortices with larger initial sizes tend to attain the greater integrated kinetic energy. The size of the latter stage has a high correlation (no less than 0.45) with the initial R26 for 66 h, indicating that the initial size of TCs can be a key predictor. The peak of size change rate (ΔR26) is located at moderate intensity (25~50 m·s-1) and the peak intensity change rate (ΔVmax) is located at medium and small size (50-100 km). The outer-core size is more likely to expand outward and even leads to rapid expansion under the conditions of stronger upper air divergence, higher relative humidity, larger ocean heat content and moderate vertical shear.

T91 steel is one of the candidate structural materials for the fourth generation reactor. The high temperature creep property after neutron irradiation is the key index to evaluate its service performance. In order to make full use of irradiation space, reduce irradiation parameter gradient and reduce specimen radioactivity, small-size specimens are needed for studying mechanical properties. However, the test data of small-size specimens may be different from that of standard specimens, which leads to the inaccuracy evaluation of material properties. In order to study the effect of specimen size change on the creep mechanical behavior of T91 steel, creep tests of standard rod specimens and small piece specimens of T91 steel in the temperature range of 675-725 ℃ and creep stress range of 80-120 MPa were carried out, the creep behavior and fracture mechanism of T91 steel between two specimens under the same test conditions were compared, the mechanism of influence of specimen size on creep properties was deduced, and the variation of size effect with creep temperature and stress and its reason were analyzed. Comparing and analyzing the creep test results of the two specimens, it is found that creep curves of two specimens of T91 steel under various test conditions consist of three stages—primary creep stage, steady-state creep stage and accelerated creep stage. With the increase of test temperature and creep stress, the steady-state creep stage shortens, the rupture time of T91 steel decreases and the steady creep rate increases. Compared with the standard rod specimen, the small piece specimen has longer creep rupture time and smaller steady-state creep rate. The creep activation energy of the two specimens is roughly the same, which means that the change of specimen size does not affect the creep deformation mechanism of T91 steel, while the reason for the difference is the difference of specimen stress state. Microanalysis results show that the fractures of all specimens are microporous aggregation ductile fracture, which means specimen size does not affect creep fracture type of T91 steel in microscopic scale. The dimple size of the small piece specimen fracture is relatively smaller, which means the poor creep fracture plasticity of small piece specimen. The dimples on the creep fracture of standard rod specimens are mainly equiaxed dimples, but the dimples on the creep fracture of small piece specimens are mainly equiaxed dimples, which means specimen size has effect on the macro fracture mode of T91 steel. Based on the creep test results, microanalysis results and relevant literature research, it can be found that specimen size affects creep properties of T91 steel by affecting the stress state of the specimen, different processes of microstructure evolution in the creep process is an important reason for the complex variation law of creep specimen size effect with the creep temperature and stress, and the effect of oxidation on size effect is not obvious.

Abstract Specimen‐based data have played a central role in documenting body‐size shifts as a possible response to global warming over the last century. Identification of the drivers and patterns of these trends requires comparisons across taxa, often through meta‐analyses; however, a lack of repeatability within and interoperability (i.e. the potential for a dataset to be augmented for future research) among published studies is a major obstacle. We reviewed published studies on mammal body‐size changes in the Anthropocene, focusing on those that used museum specimens to analyse body‐size trends over time in at least one species. We assessed these papers for repeatability and interoperability with the following criteria: raw data and specimen identifiers were published and accessible, measurements were unambiguously defined, and potential sex‐ and age‐based size differences among individuals were accounted for. Most published body‐size studies have low potential for replication or augmentation; only one of 27 met all of our criteria. Although these 27 papers collectively generated an estimated 51,790 new body‐size measurements, only 1.25% (649) could be repeated or readily used in further investigations, as the remainder did not include raw data and/or specimen identifiers. Based on these findings, we recommend the following best practices in the study of body‐size trends. First, authors should explicitly define and justify all measures of size and quantify measurement error and publish all data, including measurements and specimen catalogue numbers. In addition to complying with the fundamental scientific tenet of repeatability, this minimizes redundant handling and the concomitant risk of damage to irreplaceable and often fragile museum specimens. Second, authors should test and account for the effects of demography, as some dimensions can change throughout an individual's life. Adopting these practices will improve the quality of body‐size studies, enhance the utility of extended specimen data from natural history collections, and enable researchers to conduct more expansive investigations of size trends over time.

Background: RECIST criteria for progressive disease, partial response, and complete response, reflecting +20%, -30%, and -100% tumor size changes, respectively, are critical outcome variables in oncology clinical trials. Herein, we evaluated post-immunotherapy tumor size change correlation with outcomes., Methods: We used a unique clinical trial data resource, a multicenter basket trial in patients with rare solid tumors treated with nivolumab (anti-PD-1) and ipilimumab (anti-CTLA-4) between 2017 and 2023 (National Cancer Institute/Southwest Oncology Group-sponsored DART trial [NCT02834013]) (open at 1083 sites at its peak). Outcome associations were evaluated by survival analysis techniques including Martingale residuals., Results: In 638 evaluable patients, we found strong linear relationships between percent change in tumor measurement up to a 40%-50% increase and progression-free (PFS) and overall survival (OS) (both Cox regression P < .001; landmark analyses based on day 65). Pearson R correlation between survival estimates and tumor change category were -0.94, -0.89, and -0.89 (PFS) and -0.84, -0.90, and -0.90 (OS) for median, 6-month (PFS), and 1-year (OS) and for 1-year (PFS) and 2-year (OS) estimates., Conclusions: Percent change in tumor measurement per RECISTv1.1 (the sum of longest dimensions of target lesions) has a linear association with PFS and OS up to a 40% to 50% increase in tumor measurement in this cohort of patients with rare cancers who received combination immune checkpoint blockade. Quantitative first scan tumor measurement changes include important information to evaluate the potential efficacy of a therapy beyond the proportion of patients who achieve an objective response., (© The Author(s) 2024. Published by Oxford University Press. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

AIM: To explore the photopic pupil size behavior in myopic children undergoing overnight orthokeratology (ortho-k) over 1-year period and its effects on the axial elongation. METHODS: A total of 202 Chinese myopic children were enrolled in this prospective clinical trial. Ninety-five subjects in ortho-k group and eighty-eight subjects in spectacle group completed the 1-year study. Axial length (AL) was measured before enrollment and every 6mo after the start of ortho-k. The photopic pupil diameter (PPD) was determined using the Pentacam AXL and measured in an examination room with lighting of 300-310 Lx. Stepwise multiple linear regression analysis was used to identify variables contribution to axial elongation. RESULTS: Compared with spectacle group, the average 1-year axial elongation was significantly slower in the ortho-k group (0.25±0.27 vs 0.44±0.23 mm, P0.05, Bonferroni correction). The 4.81 mm PPD may be a possible cutoff point in the ortho-k group. Subjects with PPD below or equal to 4.81 mm tended to have smaller axial elongation compared to subjects with PPD above 4.81 mm after 1-year period (t=-3.09, P=0.003). In ortho-k group, univariate analyses indicated that those with older age, greater degree of myopia, longer AL, smaller baseline PPD (PPDbaseline) experienced a smaller change in AL. In multivariate analyses, older age, greater AL and smaller PPDbaseline were associated with smaller increases in AL. In spectacle group, PPD tended to be stable (P>0.05, Bonferroni correction) and did not affect axial growth. CONCLUSION: PPDs experience significantly decreases at 1-month and 3-month ortho-k treatment. Children with smaller PPD tend to experience slower axial elongation and may benefit more from ortho-k.

The solid and gaseous residues of coal dust explosion are the physical evidence for analyzing the detonation site and propagation path and the basis for deploying rescue work. The 20 L spherical explosion system is used to conduct explosion experiments on lignite coal dust with different concentrations and particle sizes. And the particle size change of the solid residue and the flammability of the gaseous residue of the lignite coal dust explosion are analyzed. The results show that the particle size range of lignite coal dust explosion solid residues is larger than that of the original lignite coal dust. When the coal dust concentration is constant, as the particle size decreases, the D10 change rate of lignite coal dust explosion solid residues tends to increase negatively, the D50 change rate fluctuates in the range of 10% to 20%, and the D90 change rate tends to increase positively. When the coal dust particle size is constant, as the coal dust concentration increases, the D10 of the lignite coal dust explosion solid residue first decreases and then increases, while the D50 and D90 continue to increase. The lignite coal dust explosion gaseous residue mainly contains O2, CO, H2,CO2,CH4,C2H6,C2H4,C2H2 and C3H6. As the particle size of coal dust decreases or the concentration increases, the content of O2 and CO2 in the gaseous residue decreases continuously, and the content of hydrocarbon gases such as CO, H2 and CH4 increases continuously. When the coal dust particle size is constant, the flammability index of lignite coal dust explosion gaseous residue within the concentration range of 100-200 g/m3 is less than 1, indicating that the gaseous residue is not combustible. The flammability index of lignite coal dust explosion gaseous residue within the concentration range of 300-600 g/m3 is greater than 1, indicating that the gaseous residue is combustible. When the coal dust concentration is constant, the flammability index of lignite coal dust explosion gaseous residue with the particle size of 180-250 μm is less than 1, indicating that the gaseous residue is not combustible. The flammability index of lignite coal dust explosion gaseous residue with the particle size of 38-180 μm is greater than 1, indicating that the gaseous residue is combustible. The content of H2 and CO in the gaseous residue is the key factor affecting the flammability of lignite coal dust explosion gaseous residue. The flammability is mostly affected by H2, followed by CO.