Search

OBJECTIVES This study was designed to examine the outcomes of adult living-donor lobar lung transplants (LDLLTs) using small-for-size grafts. METHODS A calculated graft forced vital capacity of <50% of the predicted forced vital capacity of the recipient was considered to indicate a small-for-size graft. Adult recipients (≥18 years) who underwent LDLLTs between 2008 and 2022 were included in this study. RESULTS We performed 80 adult LDLLTs, using small-for-size grafts in 15 patients and non-small grafts in 65 patients. Grade 3 primary graft dysfunction developed within 72 h after the transplant in 3 patients (20%) in the small group and in 3 patients (4.6%) in the non-small group (P  = 0.0763). The 1- and 5-year survival rates were 86.7% and 69.3% in the small group and 93.8% and 77.1% in the non-small group (P  = 0.742). In the small group, the native lungs were spared in 8 patients, whereas 2 lobar grafts were implanted with non-spared native lungs in the other 7 patients. The 1- and 5-year survival rates were significantly better in the spared group (both 100%) than in the non-spared group (71.4% and 23.8%; P  = 0.0375). The spared group showed a significantly higher median percent forced vital capacity after the transplant than the non-spared group (68.5% vs 44.9%; P  = 0.0027). CONCLUSIONS Although the use of small-for-size grafts was associated with a higher rate of severe primary graft dysfunction, no differences were found in survival rates. When the graft is small, the native lung should be partially spared if possible. [ABSTRACT FROM AUTHOR]

Cardiac volume-based estimation offers an alternative to donor-recipient weight ratio (DRWR) in pediatric heart transplantation (HT) but has not been correlated to posttransplant outcomes. We sought to determine whether estimated total cardiac volume (eTCV) ratio is associated with HT survival in infants. The United Network for Organ Sharing database was used to identify infants (aged <1 year) who received HT in 1987-2020. Donor and recipient eTCV were calculated from weight using previously published data. Patient cohort was divided acc ording to the significant range of eTCV ratio; characteristics and survival were compared. A total of 2845 infants were identified. Hazard ratio with cubic spline showed prognostic relationship of eTCV ratio and DRWR with the overall survival. The cut point method determined an optimal eTCV ratio range predictive of infant survival was 1.05 to 1.85, whereas no range for DRWR was predictive. Overall, 75.6% of patients had an optimal total cardiac volume ratio, while 18.1% were in the lower (LR) and 6.3% in the higher (HR) group. Kaplan-Meier analysis showed better survival for patients within the optimal vs LR (p = 0.0017) and a similar significantly better survival when compared to HR (p = 0.0053). The optimal eTCV ratio group (n = 2,151) had DRWR, ranging from 1.09 to 5; 34.3% had DRWR of 2% to 3%, and 5.0% had DRWR of >3. Currently, an upper DRWR limit has not been established in infants. Therefore, determining the optimal eTCV range is important to identify an upper limit that significantly predicts survival benefit. This finding suggests a potential increase in donor pool for infant recipients since over 40% of donors in the optimal eTCV range include DRWR values >2 that are traditionally not considered for candidate listing. [ABSTRACT FROM AUTHOR]

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]

Lung transplantation is an established management strategy for advanced end-stage lung disease with the goal of restoring normal pulmonary physiology. This principle guided our management approach to the clinical challenge of a lung transplant recipient with a small chest cavity from fibrotic lung disease. Size matching should occur based on the recipient’s predicted total lung capacity, which best reflects the recipient’s normal chest cavity size. We present an instructive case that suggests that the small chest cavity size adjusts relatively quickly toward normal once the fibrotic lungs are removed, and normal allograft is implanted.

Living-donor lobar lung transplantation (LDLLT) is indicated for critically ill patients who would not survive the waiting period in the case of severe brain-dead donor shortage. It is essential to confirm that potential donors are willing to donate without applying psychological pressure from others. In standard LDLLT, the right and left lower lobes donated by 2 healthy donors are implanted into the recipient under cardiopulmonary support. LDLLT can be applied to various lung diseases including restrictive, obstructive, infectious, and vascular lung diseases in both adult and pediatric patients if size matching is acceptable. Functional size matching by measuring donor pulmonary function and anatomical size matching by 3-dimensional computed tomography volumetry are very useful. When 2 donors with ideal size matching are not available, various transplant procedures, such as single lobe, segmental, recipient lobe-sparing, and inverted lobar transplants are valuable options. There seems to be immunological advantages in LDLLT as compared to cadaveric lung transplantation (CLT). Unilateral chronic allograft dysfunction is a unique manifestation after bilateral LDLLT, which may contribute to better prognosis. The growth of adult lung graft implanted into growing pediatric recipients is suggested by radiologic evaluation. Although only 2 lobes are implanted, postoperative pulmonary function is equivalent between LDLLT and CLT. The long-term outcome after LDLLT is similar to or better than that after CLT. The author has performed 164 LDLLTs resulting in 71.6% survival rate at 10 years. All living-donors returned to their previous life styles. Because of possible serious morbidity in donors, LDLLT should be applied only for critically ill patients. [ABSTRACT FROM AUTHOR]

BackgroundDonor/recipient size matching is paramount in heart transplantation. Body weight, height, body mass index, body surface area, and predicted heart mass (PHM) ratios are generally used in size matching. Precise size matching is important to achieve better clinical outcomes. This study aims to determine the donor/recipient ascending aortic diameter (AAoD) ratio as a metric for donor selection and its effect on postoperative clinical outcomes in heart transplant patients.MethodsWe retrospectively reviewed all consecutive patients who underwent heart transplantation from January 2015 to December 2018. A cutoff value of 0.8032 for the donor/recipient AAoD ratio (independent variable for the primary endpoint during unmatched cohort analysis) was determined for predicting in-hospital mortality. The patients were divided into two groups based on the cutoff value. Group A, AAoD < 0.8032 (n = 96), and Group B, AAoD > 0.8032 (n = 265). A propensity score-matched (PSM) study was performed to equalize the two groups comprising 77 patients each in terms of risk. A Cox regression model was developed to identify the independent preoperative variables affecting the primary end-point. The primary endpoint was all-cause in-hospital mortality.ResultsA total of 361 patients underwent heart transplantation during the given period. On the multivariate analysis, donor/recipient PHM ratio [HR 16.907, 95% confidence interval (CI) 1.535–186.246, P = 0.021], donor/recipient AAoD ratio 0.8032 could improve post-heart transplantation outcomes and donor heart utilization.

Nano-particles possess desirable attributes such as small particle size, excellent injectivity, and migration performance, making them highly compatible and adaptable for addressing the water flooding requirements of the low-permeability oil reservoir. When selecting an oil displacement agent for enhancing water flooding and improving oil recovery, factors such as injectivity and migration need to be carefully considered. In this study, through a comprehensive analysis of the mechanism and technical characteristics of nano-particle oil displacement agents, the plugging and profile control mechanisms recognized by the mainstream of nano-particles are elucidated. By examining various elements including outcrop fractures, natural micro-fractures, artificial support fractures, and dynamic monitoring data, a reevaluation of the dominant channel scale governing water drive in low permeability reservoirs is conducted, thereby defining the target entities for profile control and flooding operations. Drawing upon Darcy’s percolation law and leveraging enhanced oil recovery techniques based on the classical Kozeny equation, a profile control and flooding mechanism is proposed that focuses on increasing the specific surface area of polymer particles while simultaneously reducing reservoir permeability. This innovative approach establishes a novel matching method between nano-polymer particles and the diverse media found within the reservoir. Lastly, the application of nanoparticle flooding technology in Changqing Oilfield is presented, highlighting its practical implementation and benefits.

In standard bilateral living-donor lobar lung transplantation (LDLLT), right and left lower lobes donated by 2 healthy donors are implanted into a recipient after right and left pneumonectomies. Because only 2 lobes are implanted, the grafts may be too small for an adult recipient. To overcome size mismatch, we have developed a technique of right-to-left inverted LDLLT based upon the fact that the right lower lobe is generally larger than the left lower lobe. In right-to-left inverted LDLLT, 2 donors donate their right lower lobes. The right graft is implanted in the right side of the recipient. The left graft is inverted and implanted in the left side. This operation is indicated when total graft forced vital capacity (FVC) is less than 60% of the recipient's predicted FVC or when donor's left lower lobectomy is technically difficult due to interlobar pulmonary artery anatomy. [ABSTRACT FROM AUTHOR]

The article discusses a study on double lung transplants, comparing right-first implantation to left-first implantation. The study found that right-first implantation reduced the need for intraoperative ECMO support and decreased the incidence of primary graft dysfunction grade 3 at 72 hours. The authors suggest that the size of the vascular bed in the right lung may play a role in these outcomes, and emphasize the importance of donor-to-recipient size matching in lung transplantation. [Extracted from the article]

In pediatric heart transplantation, donor: recipient weight ratio (DRWR) has long been the sole metric for size matching. Total cardiac volume (TCV)-based size matching has emerged as a novel method to precisely identify an upper limit of donor organ size of a heart transplant recipient while minimizing the risk of complications from oversizing. The clinical adoption of donor: recipient volume ratio (DRVR) to prevent short-term adverse outcomes of oversizing is unknown. The purpose of this single-center study is to determine the relationship of DRWR and DRVR to the risk of post-operative complications from allograft oversizing. Recipient TCV was measured from imaging studies and donor TCV was calculated from published TCV prediction models. DRVR was defined as donor TCV divided by recipient TCV. The primary outcome was short-term post-transplant complications (SPTC), a composite outcome of delayed chest closure and prolonged intubation > 7 days. A multivariable logistic regression model of DRWR (cubic spline), DRVR (linear) and linear interaction between DRWR and DRVR was used to examine the probability of experiencing a SPTC over follow-up as a function of DRWR and DRVR. A total of 106 transplant patients' records were reviewed. Risk of the SPTC increased as DRVR increased. Both low and high DRWR was associated with the SPTC. A logistic regression model including DRWR and DRVR predicted SPTC with an AUROC curve of 0.74. [95% CI 0.62 0.85]. The predictive model identified a "low-risk zone" of donor-recipient size match between a weight ratio of 0.8 and 2.0 and a TCV ratio less than 1.0. DRVR in combination with DRWR predicts short-term post-transplant adverse events. Accepting donors with high DRWR may be safely performed when DRVR is considered. [ABSTRACT FROM AUTHOR]

• Composites are prepared based on the principle of "host-guest adaptation". • PMo 4 @UiO-67 displays good desulfurization activity and reusability. • The desulphurization efficiency of different sulfides was compared. • The possible mechanism of the reaction was investigated. Deep desulphurization of diesel is essential because the sulfides from fuel combustion can cause acid rain, respiratory diseases and corrosion of industrial equipment. Peroxophosphomolybdate (BTA) 3 {PO 4 [MoO(O 2) 2 ] 4 }·3H 2 O, marked as PMo 4 , was confined in size-matched Zr-MOFs (UiO-66 and UiO-67) to prepared composites for extractive oxidative desulfurization. The composites underwent comprehensive characterization, including ICP-MS, FT-IR, XRD, SEM, XPS, TG and N 2 adsorption–desorption analysis. Desulfurization test was conducted with PMo 4 as homogeneous catalyst, and the reaction conditions were optimized. Then, the catalytic activity of the prepared composites was compared, and the result showed that the catalyst PMo 4 @UiO-67 can remove 94.1 % of the sulfides in the diesel within 100 min. After 15 consecutive tests, the total removal rate of sulfides still reached 88.5 %, thanks to the narrow window of carrier UiO-67 limited the leaching of the active component PMo 4. [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]

Purpose: A difference in the lower body to upper body ratio between similarly heighted individuals could lead to inadequately matched transplants. There has been a perception in clinical circles that body ratio varies between people of different races, and investigating this supposition would prove useful in increasing transplant match accuracy. The investigation's purpose was to derive an equation with a greater correlation to lung length than height alone. Methods: Lung transplantation donor data for 480 adult patients was obtained and divided by ethnicity—Caucasian, African American, and Hispanic. Height, weight, age, sex, right and left lung length were evaluated for significance. The R2 value of the multiple linear regression with these variables vs. lung length was determined and tested in a separate dataset of 100 patients. Results: Only the distribution of height was significant between the 3 ethnicities (P = 0.041). None of the ANCOVAs were significant (P < 0.05) or near significant (P < 0.10). For the strongest correlation model with lung length, height had a linear fit, weight had a cubic fit, and age had a logistic fit. Multiple regression models were successfully created for right lung (R2 = 0.202) and left lung (R2 = 0.213). Independent testing showed a correlation of 0.131 and 0.136, respectively. Conclusion: Using demographic information from the donor and recipient as proxies for estimating lung size should only serve as a rough guide due to their weak correlation with lung length. As a result, for greater accuracy, donor-recipient matching should be individualized by taking donor and recipient chest X-Rays and/or TLC into consideration. [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]

Lobar lung transplantation (LLTx) from deceased donors is a potential solution for donor–recipient size mismatch for small sized recipients. We reviewed our institutional experience to compare outcomes after LLTx to standard lung transplantation (LTx). We retrospectively reviewed transplants in our institution from January 2000 to December 2017. LLTx early- and long-term outcomes were compared with LTx. Additional analysis of outcomes was performed after dividing the cohort into 2 eras (era 1, 2000-2012; era 2, 2013-2017). Among the entire cohort (1665), 75 were LLTx (4.5%). Compared with LTx, LLTx were more frequently bridged to transplant with extracorporeal life support or mechanical ventilation and were transplanted in a rapidly deteriorating status (respectively, 20% vs 4.4%, P =.001; 22.7% vs 7.9, P <.001; and 41.3% vs 26.5%, P =.013). LLTx had longer intensive care unit and hospital lengths of stay (respectively, median 17 vs 4 days, and 45 vs 23, both P <.001), and greater 30-day mortality (13.3% vs 4.3%, P =.001) and 90-day mortality (17.3% vs 7.2%, P =.003). In era 2, despite a significantly greater 30-day mortality (10.8% vs 2.8%, P =.026), there was no significant difference in 90-day mortality between LLTx and LTx (13.5% vs 5.1%, P =.070). Overall survival at 1, 3, and 5 years was not significantly different between LLTx and LTx (73.2% vs 84.4%, 56.9% vs 68.4% and 50.4% vs 55.8, P =.088). Although LLTx is a high-risk procedure, both mid- and long-term survival are comparable with LTx in all cohorts in the modern era. LLTx therefore represents a valuable surgical option for small-sized recipients. Lobar lung transplant should be considered a valid option for pediatric and small-sized recipients, as they have longer times on the waiting list. Survival has improved in the modern era, with equivalent 90-day and long-term survival when compared with standard bilateral lung transplant. [Display omitted] [ABSTRACT FROM AUTHOR]

Size-matching donors to recipients in lung transplantation continues to be a clinical challenge. Predicted total lung capacity equations, or more simply, donor and recipient heights, while widely used, are imprecise and may not be representative of the pool of donors and recipients. These inherent limitations may result in size discrepancies. The advent of easily accessible software and the widespread availability of computed tomography (CT) imaging in donor assessments have made it possible to directly measure lung volumes in donors and recipients. As a result, there is a growing interest in adopting personalized CT volumetry as an alternative. This article explores both methods and underscores the potential benefits and precision offered by CT., Competing Interests: Declaration of competing interest The authors of this manuscript have no conflicts of interest to disclose, as described by the American Journal of Transplantation., (Copyright © 2024 American Society of Transplantation & American Society of Transplant Surgeons. Published by Elsevier Inc. All rights reserved.)

The pediatric heart transplant community uses weight-based donor-to-recipient size matching almost exclusively, despite no evidence to validate weight as a reliable surrogate of cardiac size. Donor size mismatch is the second most common reason for the refusal of donor hearts in current practice (∼30% of all refusals). Whereas case-by-case segmentation of total cardiac volume (TCV) by computed tomography (CT) for direct virtual transplantation is an attractive option, it remains limited by the unavailability of donor chest CT. We sought to establish a predictive model for donor TCV on the basis of anthropomorphic and chest X-ray (CXR) cardiac measures. Banked imaging studies from 141 subjects with normal CT chest angiograms were obtained and segmented using 3-dimensional modeling to derive TCV. CXR data were available for 62 of those subjects. A total of 3 predictive models of TCV were fit through multiple linear regression using the following variables: Model A (weight only); Model B (weight, height, sex, and age); Model C (weight, height, sex, age, and 1-view anteroposterior CXR maximal horizontal cardiac width). Model C provided the most accurate prediction of TCV (optimism corrected R2 = 0.99, testing set R2 = 0.98, mean absolute percentage error [MAPE] = 8.6%) and outperformed Model A (optimism corrected R2 = 0.94, testing set R2 = 0.94, MAPE = 16.1%) and Model B (optimism corrected R2 = 0.97, testing set R2 = 0.97, MAPE = 11.1%). TCV can be predicted accurately using readily available anthropometrics and a 1-view CXR from donor candidates. This simple and scalable method of TCV estimation may provide a reliable and consistent method to improve donor size matching. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Harbin University of Science & Technology is the property of Journal of Harbin University of Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Betaine surfactants reduce oil–water interfacial tension (IFT) to an ultralow level through the synergistic effects between the surfactants and the active components of crude oil. These surfactants exhibit potential for applications in chemical flooding. However, the synergistic effect is affected by the structure of betaine and the properties of the aqueous phase. In this study, the dynamic and equilibrium IFTs of a series of betaine surfactant solutions against crude oil were measured under different aqueous phase conditions. The results indicate that the sizes of the hydrophobic and hydrophilic groups of betaine considerably affect its ability to reduce the IFT against crude oil. In addition, the weak base sodium bicarbonate (NaHCO 3) in formation water reacts with petroleum acid and considerably promotes the mixed adsorption of crude oil components at the interface. As a result, the synergistic effect of IFT reduction between betaine and crude oil is strongly enhanced. Therefore, betaine molecular size and aqueous-phase pH are two major factors affecting the synergistic effect between betaine and crude oil. This study provides theoretical and practical guidance for chemical flooding to achieve enhanced oil recovery. [Display omitted] • The ultralow interfacial tension can be obtained when the size of betaine matches that of active components. • The divalent cations have little effect on the interfacial tensions of electrically neutral betaine solutions. • The reaction of alkali and petroleum acid can enhance the synergistic effect of betaine and crude oil. • The weak base in formation water is the main factor to produce ultra-low interfacial tension. [ABSTRACT FROM AUTHOR]

• 20 mm talar osteochondral grafts have similar profiles without size matching. • 30 mm talar grafts are similar within the male sex (female sex not investigated). • All tali have similar curvatures and profiles on the talar dome. • Size matching is not required for >20 mm talar ostechondral allografts. • Only sex matching is required if the graft is between 20–30 mm in length. Traumatic injury and idiopathic avascular necrosis of the talus bone can result in osteochondral lesions of the talus leading to pain, motion loss, and disability. Treatment with osteochondral allografting currently requires the donor talus to be size matched to the recipient talus to ensure precise fits. Eliminating or reducing the need for size matching would lessen costs and the delay between diagnosis and treatment. 3D models of 12 tali of varying sizes were used to analyze curvatures and profiles of select areas on the talar dome. The allograft procedure was mimicked to compare the results between using 20 mm and 30 mm osteochondral allografts with, and without, donor size matching. The observed curvatures and profiles on the talar dome were found to be consistent between tali of different sizes. Size matching was not required to have acceptable levels of deviation between donor and recipient tali when using 20 mm length segments. Deviations without size matching were found to be very similar to the deviations with size matching with only 14.8% of the fits without size matching having larger deviations (although less than 1.5 mm) than those with size matching. Using the 30 mm segments, there was a significant difference between the small female tali and the largest male tali. Thus, donor size matching is not necessary when treating large osteochondral lesions of the talus with an osteochondral allograft taken from the central 20 mm of the donor talar dome, and only sex matching may be necessary for 30 mm grafts. [ABSTRACT FROM AUTHOR]

Graphical abstract Theoretical critical size matching ratios (K mc ) vs. magnetic induction in pulsating HGMS of ilmenite. Highlights • The size matching ratio varies with HGMS operations and is consistent with practice. • The new description contributes to the solution for size matching in real situation. • The new theoretical description contributes to the optimal design of matrix. Abstract Magnetic element is the basic component of matrix in high gradient magnetic separation (HGMS), and its configurative parameters such as size have marked effects on the capture efficiency of the matrix. Therefore, the geometric design of the element should be matched with the properties of the material to be separated, to optimize the HGMS performance. In this work, the capture of independent magnetic particles on a cylindrical element in pulsating HGMS process was theoretically described, and their size matching ratios (magnetic element to particle) under the maximum capture probability and critical capture conditions were specifically discussed. These theoretically calculated size ratios were much larger than that (2.69) in the literatures available, but generally consistent with those obtained from pulsating HGMS applications. The theoretical analysis were basically validated by the actual capture of ilmenite and hematite particles on cylindrical elements, using an experimental magnetic capture method. According to the new theoretical model, the size matching ratio is not fixed at the value of 2.69. It depends on the properties of the material to be separated such as volume magnetic susceptibility and the operating parameters of a HGMS process such as magnetic induction and flow velocity through the magnetic element. This theoretical description provides a new fundamental understanding in the size matching between magnetic element and particle, and would contribute to the solution of size matching issue in the real capture situation considering the interactions between magnetic particles, and therefore to the optimal design and operations of matrix in HGMS applications. [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]

Background: Total Cardiac Volume (TCV) based size matching using Computed Tomography (CT) is a novel technique to compare donor and recipient heart size in pediatric heart transplant that may increase overall utilization of available grafts. TCV requires manual segmentation, which limits its widespread use due to time and specialized software and training needed for segmentation., Objective: This study aims to determine the accuracy of a Deep Learning (DL) approach using 3-dimensional Convolutional Neural Networks (3D-CNN) to calculate TCV, with the clinical aim of enabling fast and accurate TCV use at all transplant centers., Materials and Methods: Ground truth TCV was segmented on CT scans of subjects aged 0-30 years, identified retrospectively. Ground truth segmentation masks were used to train and test a custom 3D-CNN model consisting of a Dense-Net architecture in combination with residual blocks of ResNet architecture., Results: The model was trained on a cohort of 270 subjects and a validation cohort of 44 subjects (36 normal, 8 heart disease retained for model testing). The average Dice similarity coefficient of the validation cohort was 0.94 ± 0.03 (range 0.84-0.97). The mean absolute percent error of TCV estimation was 5.5%. There is no significant association between model accuracy and subject age, weight, or height. DL-TCV was on average more accurate for normal hearts than those listed for transplant (mean absolute percent error 4.5 ± 3.9 vs. 10.5 ± 8.5, p = 0.08)., Conclusion: A deep learning based 3D-CNN model can provide accurate automatic measurement of TCV from CT images., Competing Interests: Declarations Disclosure / Financial Conflict of Interest Statement Dr. Morales reports contributions from Cormatrix, Inc., personal fees from Syncardia, Inc., personal fees and other contributions from Abbott Medical Inc., personal fees from Xeltis, Inc., personal fees from Azyio, Inc. all outside the submitted work. All other authors have no financial conflicts of interest to disclose. Dr. Zafar is Vice President of Cardiothoracic Clinical Development at Transmedics, Inc, his employment is outside the submitted work. All other authors report no conflicts of interest. Additional Declarations: No competing interests reported.

Abstract Different types of anion vacancies were optimized in passive films on copper via first-principles calculations based on density functional theory, and numerous potentiodynamic polarizations were performed to evaluate the size matching effect between anion vacancies and halide ions in passive film breakdown on copper. The size of the anion vacancies decreased to some extent compared with the corresponding atom due to the surface relaxation effect, and electrochemical experiments showed that the pitting potential for an oxide passive film on copper followed the order F− < Cl− < Br−, while this order was Cl− < F− < Br− for a sulfide passive film, which was attributed to the integrated effect of the energy of anion vacancy expansion and the Gibbs energy of dehydration. The pitting potential orders were the same on pre-oxidized or pre-sulfided copper with that of fresh copper in the same solution. Meanwhile, iodide ions were not compared due to the formation of poorly soluble copper iodides. The ratio of pit depth to pit mouth diameter on copper decreased with increasing pit volume, resulting in shallow pits with large mouth; thus, the catalytic-occluded cell effect was not obvious for copper. [ABSTRACT FROM AUTHOR]

Diblockopolymers containing the pH-responsive monomer 2-(diethylaminoethyl) methacrylate (DEAEMA) were synthesized via RAFT polymerization. cryo-TEM imaging revealed the formation of micelles that were used for dispersion of C60 fullerenes in native pH, and their responsiveness to pH modification and salt addition was monitored at different concentrations. Concentration-dependent responsiveness was observed: Just above the CMC in native pH, pH reduction results in precipitation (release) of pre-dispersed C60. At high polymer concentrations the C60 dispersions are non-responsive. Dispersions of Carbon Black, a colloidal particle of much larger diameter, characterized as a reference system, showed a different nanomorphology and were not responsive to pH modifications, due to a different dispersion mechanism. We concluded that good size matching between the dispersed particles is necessary for the formation of micelle-entrapped dispersions, and that the responsivity of the C60 dispersion to pH reduction is limited to a concentration range between the CMC in native conditions and the CMC in acidic conditions. [ABSTRACT FROM AUTHOR]

Background The International Society for Heart and Lung Transplantation (ISHLT) guidelines advise against inappropriate weight match (IWM) for heart transplant, defined as donor weight <70% of recipient’s weight. Few studies have explored in detail this size-matching recommendation, especially with regard to body mass index (BMI) and gender matching. We aimed to determine whether any difference could be observed between size-matching in obese and non-obese recipients with regard to mortality after cardiac transplantation. Methods Data from 52,455 adult heart transplants (recipients ≥18 years of age) between 1994 and 2013 were obtained from the ISHLT Registry. We defined the following subgroups of patients based on BMI: underweight, BMI <18.5; non-obese, BMI 18.5 to 30; and obese, BMI >30. The end-points were all-cause 30-day mortality and cumulative mortality. Results IWM was associated with increased 30-day mortality (odds ratio [OR] = 1.20, 95% confidence interval [CI] 1.01 to 1.43, p = 0.041) and cumulative mortality (hazard ratio [HR] = 1.14, 95% CI 1.07 to 1.22, p < 0.001). In non-obese recipients, IWM was associated with increased 30-day mortality (OR = 1.89, 95% CI 1.48 to 2.41, p < 0.001) as well as cumulative mortality (HR = 1.27, 95% CI 1.15 to 1.41, p < 0.001), whereas, for obese recipients, IWM was not associated with 30-day or cumulative mortality. Male recipients of female allografts (HR = 1.08, 95% CI 1.04 to 1.12, p < 0.001) as well as female recipients of male allografts (HR = 1.07, 95% CI 1.02 to 1.13, p = 0.003) had increased cumulative mortality compared with gender-matched transplants. There was no interaction between IWM and gender mismatch. Conclusions Our results indicate that donor weight <70% of recipient weight increases mortality in non-obese heart transplant recipients, but not in obese transplant recipients. Gender mismatch increases mortality independently of weight match. [ABSTRACT FROM AUTHOR]

Copyright of China Sciencepaper is the property of China Sciencepaper and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Predicted heart mass ratio (PHMr) has been proposed as an optimal size metric in the selection of a donor heart for transplant; however, it is not known if the same size matching criteria pertains uniformly to all types of cardiomyopathies. Heart transplant recipients in the United Network for Organ Sharing registry database were categorized into 6 groups based on the type of cardiomyopathy, dilated, coronary artery disease, hypertrophic, restrictive, valvular and adult congenital heart disease. Patients in each group of etiology were stratified based on the PHMr into 5 groups: severely undersized <0.86, moderately undersized 0.86 to 0.94, matched 0.95 to 1.04, moderately oversized 1.05 to 1.24, and severely oversized >1.25. The survival and cause of death of patients in each etiology group were reviewed. The United Network for Organ Sharing registry database from January 1987 to July 2021 included 53,573 patients who received a heart transplant. Compared with patients with size matched hearts, recipients with dilated (hazard ratio 1.17, p = 0.001) and valvular (hazard ratio 1.79, p = 0.032) cardiomyopathy who had an undersized heart with PHMr <0.86 had decreased survival. In addition, the survival of patients with hypertrophic or restrictive cardiomyopathy and adult congenital heart disease was not affected by size matching based on the PHMr (0.601 and 0.079, respectively, p = 0.873). In conclusion, our analysis suggests that the size matching criteria based on PHMr may not be uniform to all patients across various etiologies of cardiomyopathy. Therefore, the data can be used to increase the acceptance rate of donor hearts, particularly, for patients with hypertrophic, restrictive cardiomyopathy and congenital heart disease in which size matching is less significant for survival outcome., Competing Interests: Declaration of Competing Interest The authors have no competing interests to declare., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Living-donor lobar lung transplantation (LDLLT) was first performed in the USA and thereafter it was introduced in Japan in 1998 as an alternative modality to brain-dead donor lung transplantation (BDLT). Although the LDLLT procedure was employed for rapidly deteriorating patients who were hospitalized and mechanically ventilated at the time of transplantation, LDLLT demonstrated better or comparable post-transplant outcomes in comparison to BDLT. Less injured lobar grafts and a significantly shorter graft ischemic time possibly contributed to a significantly lower incidence of severe primary graft dysfunction (PGD) after LDLLT in comparison to BDLT. In standard LDLLT, patients obtained lobar grafts from two different donors, and thus most patients developed chronic lung allograft dysfunction (CLAD) only in the unilateral lung graft. This indicates that the contralateral unaffected lung graft could reserve lung function after the unilateral development of CLAD. In our transplant program, the incidence of CLAD per donor in LDLLT (14.4%) was also significantly lower in comparison to BDLT (24.7%). The 1-, 5- and 10-year survival rates after LDLLT were 90.9%, 75.5% and 57.2%, respectively, which were equivalent to those after BDLT (92.9%, 73.4% and 62.2%). The inherent surgical risk to the living donors should always be considered. In our experience, living-donor surgery was associated with a complication rate of 12.7%, and importantly, all living donors finally returned to their previous social lives. Precise functional and anatomical size matching between donor lobar graft and recipient could provide a favorable pulmonary function after LDLLT. We recently established multimodal surgical approaches, such as native upper lobe-sparing, right-to-left horizontally rotated, segmental, and single-lobe transplantation, in order to resolve the issue of size mismatch between the donor lobar graft and the recipient., Competing Interests: Conflicts of Interest: Both authors have completed the ICMJE uniform disclosure form (available at https://jtd.amegroups.com/article/view/10.21037/jtd-22-1867/coif). The special series “Why is the Outcome Good? Secrets of Lung Transplantation in Japan” was commissioned by the editorial office without any funding or sponsorship. The authors have no other conflicts of interest to declare., (2023 Journal of Thoracic Disease. All rights reserved.)

Objectives In standard living-donor lobar lung transplantation (LDLLT), the right and left lower lobes from 2 healthy donors are implanted. Because of the difficulty encountered in finding 2 donors with ideal size matching, various transplant procedures have been developed in our institution. The purpose of this retrospective study was to compare outcomes of nonstandard LDLLT with standard LDLLT. Methods Between June 2008 and January 2016, we performed 65 LDLLTs for critically ill patients. Functional size matching was performed by estimating graft forced vital capacity based on the donor's measured forced vital capacity and the number of pulmonary segments implanted. For anatomical size matching, 3-dimensional computed tomography volumetry was performed. In cases of oversize mismatch, single-lobe transplant or downsizing transplant was performed. In cases of undersize mismatch, native upper lobe sparing transplant or right-left inverted transplant was performed. In right-left inverted transplants, the donor's right lower lobe was inverted and implanted into the recipient's left chest cavity. Results Twenty-nine patients (44.6%) received nonstandard LDLLT, including 12 single-lobe transplants, 7 native upper lobe sparing transplants, 6 right-left inverted transplants, 2 sparing + inverted transplants, and 2 others. Thirty-six patients (57.4%) received standard LDLLT. Three- and five-year survival rates were similar between the 2 groups (89.1% and 76.6% after nonstandard LDLLT vs 78.0% and 71.1% after standard LDLLT, P = .712). Conclusions Various transplant procedures such as single, sparing and inverted transplants are valuable options when 2 donors with ideal size matching are not available for LDLLT. [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]