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Background: Preoperative size matching is essential for both allogeneic and xenogeneic heart transplantation. In preclinical pig‐to‐baboon xenotransplantation experiments, porcine donor organs are usually matched to recipients by using indirect parameters, such as age and total body weight. For clinical use of xenotransplantation, a more precise method of size measurement would be desirable to guarantee a "perfect match." Here, we investigated the use of transthoracic echocardiography (TTE) and described a new method to estimate organ size prior to xenotransplantation. Methods: Hearts from n = 17 genetically modified piglets were analyzed by TTE and total heart weight (THW) was measured prior to xenotransplantation into baboons between March 2018 and April 2022. Left ventricular (LV) mass was calculated according to the previously published method by Devereux et al. and a newly adapted formula. Hearts from n = 5 sibling piglets served as controls for the determination of relative LV and right ventricular (RV) mass. After explantation, THW and LV and RV mass were measured. Results: THW correlated significantly with donor age and total body weight. The strongest correlation was found between THW and LV mass calculated by TTE. Compared to necropsy data of the control piglets, the Devereux formula underestimated both absolute and relative LV mass, whereas the adapted formula yielded better results. Combining the adapted formula and the relative LV mass data, THW can be predicted with TTE. Conclusions: We demonstrate reliable LV mass estimation by TTE for size matching prior to xenotransplantation. An adapted formula provides more accurate results of LV mass estimation than the generally used Devereux formula in the xenotransplantation setting. TTE measurement of LV mass is superior for the prediction of porcine heart sizes compared to conventional parameters such as age and total body weight. [ABSTRACT FROM AUTHOR]

Low‐concentration ethane capture is crucial for environmental protection and natural gas purification. The ideal physisorbent with strong C2H6 interaction and large C2H6 uptake at low‐concentration level has rarely been reported, due to the large pKa value and small quadrupole moment of C2H6. Herein, we demonstrate the perfectly size matching between the ultramicropore (pore size of 4.6 Å) and ethane (kinetic diameter of 4.4 Å) in a nickel pyridine‐4‐carboxylate metal–organic framework (IISERP‐MOF2), which enables the record‐breaking performance for low concentration C2H6 capture. IISERP‐MOF2 exhibits the large C2H6 adsorption enthalpy of 56.7 kJ/mol, and record‐high C2H6 uptake at low pressure of 0.01–0.1 bar and 298 K (1.8 mmol/g at 0.01 bar). Molecule simulations and C2H6‐loading crystal structure analysis revealed that the maximized interaction sites in IISERP‐MOF2 with ethane molecule originates the strong C2H6 adsorption. The dynamic breakthrough experiments for gas mixtures of C2H6/N2(1/999, v/v) and C2H6/CH4 (5/95, v/v) proved the excellent low‐concentration C2H6 capture performance. [ABSTRACT FROM AUTHOR]

A 16‐year‐old with new‐onset dilated cardiomyopathy underwent VAD placement, later complicated by low flow from outflow graft kinking. To expedite heart transplantation, TCV was calculated and compared with 141 normal patients pinpointing the upper weight threshold. He was transplanted 2 days later within the expanded weight range with no post‐transplant complications. [ABSTRACT FROM AUTHOR]

A long‐standing question in ecology is how species interactions are structured within communities. Although evolutionary theory predicts close size matching between floral nectar tube depth and pollinator proboscis length of interacting species, such size matching has seldom been shown and explained in multispecies assemblages. Here, we investigated the degree of size matching among Asteraceae and their pollinators and its relationship with foraging efficiency. The majority of pollinators, especially Hymenoptera, choose plant species on which they had high foraging efficiencies. When proboscides were shorter than nectar tubes, foraging efficiency rapidly decreased because of increased handling time. When proboscides were longer than nectar tubes, a decreased nectar reward rather than an increased handling time made shallow flowers more inefficient to visit. Altogether, this led to close size matching. Overall, our results show the importance of nectar reward and handling time as drivers of plant–pollinator network structure. [ABSTRACT FROM AUTHOR]

In heme, a porphyrin macrocycle naturally selects an iron ionic species. It was found that this natural combination is directly related to the geometry sizes of both components. Three series of monostrapped nonplanar metalloporphyrins [M = FeIIICl, CoII, NiII] and their metal-free counterparts were synthesized as model systems, their core sizes were compared, and density functional theory computations were used to calculate the molecular distortion energies. The results indicate that optimal size matching of both is to maintain minimal distortion energy of the macrocycle. This shows that the mutual selection process between the macrocycle and the metal ion is mainly based on the principle of minimum energy to tune the electronic structure of the central metal ion; this may be a common principle in natural tetrapyrroles containing metal species. The structural parameters of all the model compounds were directly obtained from their crystal structures. [ABSTRACT FROM AUTHOR]

An impedimetric sensor for persistent toxic substances, including organic pollutants and toxic inorganic ions is presented. The persistent toxic substances are detected using an ultrasensitive technique that is based on electron‐transfer blockage. This depends on the formation of guest–host complexes, hydrogen bonding, or a cyclodextrin (CD)‐metal complex (Mm(OH)n−β‐CD) structure between the target pollutants and β‐CD. [ABSTRACT FROM AUTHOR]

1. Changes in climatic factors could have major effects on the foraging performance of animals. To date, however, no study has attempted to examine the concurrent effect of different climatic factors on foraging performance of individual organisms. 2. In the present study, this issue was addressed by studying changes in foraging performance of seed-eating ant colonies of the genus Messor in response to variation in precipitation and ambient temperature along a macroecological gradient. In addition, we examined the way three colony-level attributes, foraging distance, forager number, and variance in worker-size, could affect foraging performance in those ants. Foraging performance was measured as size matching, i.e. the correlation between forager size and load size. The study was carried out for 2 years in six sites along a south-north productivity gradient in a semi-arid region of the Eastern- Mediterranean. 3. Size matching increased with increased precipitation as well as with an increase in worker-size variability, but slightly decreased with increasing temperatures, as predicted by foraging-decision models. In contrast, foraging distance had no effect on size matching. Interestingly, size matching showed a unimodal relationship with forager number. 4. These results indicate that interplay between climate and body size affects foraging performance either directly via physiological constraints, or indirectly through their effect on food availability. Moreover, this is one of the first evidences to support the assumption that ant colonies can differ in their ability to optimally allocate their workforce in natural environments. This emphasises the importance of studying the way foraging strategies vary across environmental gradients at macroecological scales. [ABSTRACT FROM AUTHOR]

Our aim is to develop and validate an accurate method for estimating TCV using standard echocardiographic imaging that can be easily employed to aid in donor-recipient size matching in pediatric heart transplantation. Thirty patients who underwent Echo and cardiac magnetic resonance imaging ( cMRI) were identified. TCV was measured on cMRI. TCV was determined echocardiographically by two methods: a volume measurement using the modified Simpson's method on a four-chamber view of the heart; and a calculated volume measurement which assumed a true-elliptical shape of the heart. These two methods where compared with the value obtained by cMRI using the concordance correlation coefficient (CCC). TCV by method 1 correlated well with cMRI (CCC = 0.98%, CI = 0.97, 0.99). TCV by method 2 had a CCC = 0.90 (CI = 0.9464, 0.9716) when compared to cMRI. Left ventricular end-diastolic volume (LVEDV) also correlated as a predictor of TCV in patients with structurally normal hearts and could be described by the equation: TCV = 6.6 (LVEDV) + 12 (R2 = 0.97). Echocardiographic assessment of TCV for recipients and their potential donors is a simple process and can be prospectively applied as part of donor evaluation. [ABSTRACT FROM AUTHOR]

1. Ergonomic optimisation theory proposes that by increasing variation in worker morphology, social insect colonies may increase their dietary breadth; however, little is known about how this relationship operates at the colony level. This study examines the colony-level pattern of forager size allocation to resource sites in a natural setting. 2. Using a biologically relevant measure of toughness, it is shown that leaf-cutter ant colonies exploit a variety of plant resources that vary significantly in toughness at any given time. 3. Forager size is shown to be matched to the toughness of plant material, with larger ants harvesting tougher material. 4. Furthermore, outbound foragers travelling to a harvest site are matched in size to the toughness of plant material contained within the site and are not a random selection of available foragers. The match between forager size and plant toughness may reduce the number of wasted trips and ill-matched foragers. 5. The observed colony-level pattern of forager allocation could be the result of learning by individual foragers, or the result of information shared at the colony level. [ABSTRACT FROM AUTHOR]

Background: Heart transplant waitlist mortality remains high in infants <1 year of age and among those with CHD. Currently, the median accepted donor‐to‐recipient weight percentage is approximately 130% of the recipient's weight. We hypothesized that patients with CHD may accept a larger organ using novel 3D‐derived imaging data to estimate donor and recipient TCV. Methods: A single‐center, retrospective study was performed using CT data for 13 patients with CHD and 94 control patients. 3D visualization software was used to create digital 3D heart models that provide an estimate of TCV. In addition, echocardiograms obtained prior to cross‐sectional imaging were reviewed for presence of ventricular chamber dilation. Results: Sixty‐two percent (8/13) of patients with CHD had 3D‐derived TCV resulting in a weight that was >130% larger than their actual weight. This was seen in single‐ventricle patients following Blalock‐Taussig shunt and Fontan palliation, and patients with biventricular repair. Of those, 75% (6/8) had reported moderate‐to‐severe ventricular chamber dilation by echocardiogram or cardiac magnetic resonance imaging. Conclusions: In a large portion of patients with CHD, 3D‐derived TCV place the recipient at a higher listing weight than their actual weight. We propose obtaining cross‐sectional imaging to better assess TCV in a recipient, which may increase the donor range for CHD recipients and improve organ utilization in pediatrics. [ABSTRACT FROM AUTHOR]