Discard Rate Research Articles

Improving the size selectivity of crayfish fyke-net codend, applying the hexagonal mesh and sorting grid

Context Owing to the use of fyke-nets with poor size selectivity in crayfish fishery, 40.7% of the landed undersized catch is discarded as bycatch. Aims This study investigated the effects of using hexagonal mesh (Hex34) instead of diamond nets (Com34) in the traditional crayfish fyke-net and the application of a sorting-grid (SG20, SG25, SG30) and stiff-rigged net (SRN34, SRN42, SRN50) on size selectivity. Methods A covered codend technique was used for determining the size selectivity of codends. Key results The average length at 50% retention probability (L50, in total length) for the trial groups of Com34, Hex34, SG20, SG25, SG30, SRN34, SRN42 and SRN50 was estimated as 9.1, 9.5, 10.1, 11.0, 12.3, 10.0, 10.3 and 11.1 cm respectively. Additionally, the discard rates were computed in the same order as 37.0, 27.3, 14.9, 5.8, 1.9, 19.1, 9.4 and 7.7%. Conclusions In conclusion, commercial crayfish (Com34) fyke-nets have a significantly high discard rate. In the modifications tested, the discard rate has been reduced to as low as 1.9%. When taking into account both L50 and fishing efficiency indicators, SRN42 was determined as the most successful trial group. Implications The application of the study results will make a significant contribution to the sustainability of natural crayfish stocks of Türkiye.

Certification Training and Liver Transplant Experience Improves Liver Procurement Outcomes: The Dutch Approach.

This study investigates the impact of certification training and liver transplant experience on procurement outcomes of deceased donor liver procurement in the Netherlands. Three groups (trainee, certified, and master) were formed, with further subdivision based on liver transplant experience. Three key outcomes-surgical injury, graft discard after injury, and donor hepatectomy duration-were analyzed. There were no significant differences in surgical graft injury in the three groups (trainee, 16.9%; certified, 14.8%; master, 18.2%; P = 0.357; 2011 to 2018). The only predictor for surgical graft injury was donation after circulatory death (odds ratio [OR], 1.49; 95% confidence interval [CI], 1.10-2.02). Of the three groups, the master group had the highest discard rate after surgical injury (trainee, 0%; certified, 1.3%; master, 2.8%; P = 0.013). Master group without liver transplant experience (OR, 3.16; 95% CI, 1.21-8.27) and male donor sex (OR, 3.58; 95% CI, 1.32-9.73) were independent risk factors for discarding livers after surgical injury. Independent predictors for shorter hepatectomy durations included donors older than 50 years (coefficient [Coeff], -7.04; 95% CI, -8.03 to -3.29; P < 0.001), and master group (Coeff, -9.84; 95% CI, -14.37 to -5.31; P < 0.001) and certified group with liver transplant experience (Coeff, -6.54; 95% CI, -10.83 to -2.26; P = 0.003). On the other hand, master group without liver transplant experience (Coeff, 5.00; 95% CI, 1.03-8.96; P = 0.014) and donation after circulatory death (Coeff, 10.81; 95% CI, 8.32-13.3; P < 0.001) were associated with longer hepatectomy durations. Training and certification in abdominal organ procurement surgery were associated with a reduced discard rate for surgical injured livers and shorter hepatectomy times. The contrast between master group with and without liver transplant experience underscores the need for specialized training in this field.

Review of methodologies for detecting an observer effect in commercial fisheries data

Observers are deployed on commercial fishing trips to collect representative samples of discard rates. However, fishers may change their fishing habits when an observer is onboard (“observer effect”) or observer programs may over- or under-sample portions of the fleet (“deployment effect”). If the extent of these effects are substantial, observer data will not be representative of unobserved trips, potentially biasing the estimation of discards. This sampling bias can impact catch monitoring, stock assessments, and fishery management. The purpose of this study was to examine the power and error rate of several published methods for detecting an observer effect using a simulation of observer and deployment effects at varying sampling ratios (i.e., observer coverage) for several sample statistics. The simplest methods (t-test and F-test for difference of means and variances) provided an accurate although imprecise estimate of the observer effect size, but only when there were no deployment effects. A generalized linear mixed effects model (GLMM) was also not reliable for detecting small bias, but was not confounded by deployment effects and was relatively robust to changing coverage rates. The most complicated tests involved comparing differences in trip characteristics between subsequent trips for observed-unobserved and unobserved-unobserved pairs. These tests were able to detect smaller observer effects and were not confounded by deployment effects, but were unreliable at high coverage rates (>60%), producing both high false positive and false negative rates. Sensitivity tests also showed differing detection accuracy as the distribution of the metric of interest changed. Thus, the optimal test for detecting an observer effect will depend on the metric of interest, the coverage rate, and whether a deployment effect exists. An example from the New England groundfish fishery is provided to illustrate how conflicting results may be explained. Results should always be considered carefully when declaring that an observer effect is or is not occurring because of the sensitivity of the tests.

Wasted Potential: Decoding the Trifecta of Donor Kidney Shortage, Underutilization, and Rising Discard Rates

Kidney transplantation is a life-saving intervention for end-stage renal disease; yet, the persistent gap between organ demand and supply remains a significant challenge. This paper explores the escalating discard rates of deceased donor kidneys in the United States to assess trends, discard reasons, demographical differences, and preservation techniques. Data from the Scientific Registry of Transplant Recipients from 2010 to 2021 was analyzed using chi-squared tests for trend significance and logistic regression to estimate odds ratios for kidney discard. Over the last decade, discard rates have risen to 25% in 2021. Most discarded kidneys came from extended criteria donor (ECD) donors and elevated kidney donor profile index (KDPI) scores. Kidney biopsy status was a significant factor and predictor of discard. Discard rates varied greatly between Organ Procurement and Transplantation Network regions. Of reasons for discard, “no recipient located” reached a high of 60%. Additionally, there has been a twofold increase in hypothermic machine perfusion (HMP) since 2010, with transportation difficulties being the main reason for the discard of perfused kidneys. Our findings suggest a need to recalibrate organ utilization strategies, optimize the use of lower-quality kidneys through advanced preservation methods, and address the evolving landscape of organ allocation policies to reduce kidney discard rates.

O92: Machine perfusion in liver transplantation; Cochrane review and meta-analysis

Abstract Introduction Several novel machine perfusion technologies have been developed which attempt to improve outcomes compared with ice-box static cold storage (SCS). We aimed to evaluate the effects of different methods of machine perfusion liver transplantation. Methods We used standard, extensive Cochrane search methods to identify randomised machine perfusion trials. Data extraction was performed independently by two authors. Pairwise random-effects meta-analysis was performed. We assessed bias using Risk of Bias 2 and used GRADE to assess certainty of evidence. Results We included seven randomised trials (1024 transplant recipients from 1301 randomised/included livers); four compared end-ischaemic hypothermic oxygenated perfusion (HOPE) with SCS, and three compared normothermic machine perfusion (NMP) with SCS. When compared with SCS, HOPE was associated with improvement in the following clinically relevant outcomes: graft survival (HR=0.45, 95% CI=0.23-0.87; P=0.02; high-certainty evidence), serious adverse events (OR=0.45, 0.22-0.91; P=0.03; moderate-certainty evidence) and clinically significant ischaemic cholangiopathy (OR=0.31, 0.11-0.92; P=0.03; high-certainty evidence). NMP was not associated with improvement in any of these clinically relevant outcomes, although evidence for these outcomes was low certainty. NMP was associated with improved utilisation compared with SCS (one trial found a 50% lower rate of organ discard; P = 0.008). Conclusions Where the decision has been made to transplant a DCD or marginal DBD liver, HOPE will provide superior clinically relevant outcomes compared with SCS alone (graft survival, adverse events, cholangiopathy). NMP appears to improve utilisation of grafts that would otherwise be discarded, but well-powered trials specifically designed to assess utilisation are required.

Understanding the dynamics of deceased organ donation and utilization in Colombia.

To obtain a comprehensive overview of organ donation, organ utilization, and discard in the entire donation process in Colombia. A retrospective study of 1 451 possible donors, distributed in three regions of Colombia, evaluated in 2022. The general characteristics, diagnosis, and causes of contraindication for potential donors were described. Among the 1 451 possible donors, 441 (30.4%) fulfilled brain death criteria, constituting the potential donor pool. Families consented to organ donation in 141 medically suitable cases, while 60 instances utilized legal presumption, leading to 201 eligible donors (13.9%). Of those, 160 (11.0%) were actual donors (in whom operative incision was made with the intent of organ recovery or who had at least one organ recovered). Finally, we identified 147 utilized donors (10.1%) (from whom at least one organ was transplanted). Statistically significant differences were found between age, sex, diagnosis of brain death, and donor critical pathway between regions. A total of 411 organs were transplanted from 147 utilized donors, with kidneys being the most frequently procured and transplanted organs, accounting for 280 (68.1%) of the total. This was followed by 85 livers (20.7%), 31 hearts (7.5%), 14 lungs (3.4%), and 1 pancreas (0.2%). The discard rate of procured deceased donors was 8.1%. About one-tenth of donors are effectively used for transplantation purposes. Our findings highlight areas of success and challenges, providing a basis for future improvements in Colombia.

Evaluation of word embedding models used for diachronic semantic change analysis

In the last decade, the quantitative analysis of diachronic changes in language and lexical semantic changes have become the subject of active research. A significant role was played by the development of new effective techniques of word embedding. This direction has been effectively demonstrated in a number of studies. Some of them have focused on the analysis of the optimal type of word2vec models, hyperparameters for training, and evaluation techniques. In this research, we used Corpus of Historical American English (COHA). The paper demonstrates the results of multiple training runs and the comparison of word2vec models with different variations of hyperparameters used for lexical semantic change detection. In addition to traditional word similarities and analogical reasoning tests, we used testing on an extended set of synonyms. We have evaluated word2vec models on the set of more than 100,000 English synsets that were randomly selected from the WordNet database. We have shown that changing the word2vec model parameters (such as a dimension of word embedding, a size of context window, a type of model, a word discard rate etc.) can significantly impact on the resulting word embedding vector space and the detected lexical semantic changes. Additionally, the results strongly depended on properties of the corpus, such as word frequency distribution.

Capacity configuration strategy for wind-photovoltaic-battery system based on optimized simulated annealing

Abstract Photovoltaic (PV) and wind power are very promising renewable energy sources. Wind-PV has good complementarity, and the battery can better smooth the power fluctuation of wind-PV, so the wind-PV-battery system has been widely used. The capacity configuration of the wind-PV-battery system is a complex issue because many factors affect it. Unlike other studies that focus on many meaningless parameters, the contribution of this paper is that we focus on three key elements, system reliability, cost, and wind-PV energy discard rate (EDR), which are the key factors affecting the capacity configuration of the system because system reliability and cost are factors that cannot be ignored during system operation. At the same time, the EDR is the government’s minimum requirement for system operation. Based on this, this paper establishes an optimization function to minimize the loss of power supply probability (LPSP), cost, and EDR, and then optimizes a simulated annealing (SA) algorithm to improve its optimization speed as well as accuracy, and finally verifies through simulation, that the optimized SA has better performance and can obtain a satisfactory reference configuration for wind-PV-battery capacity. Further, we have also analyzed the effectiveness obtained by applying retired batteries to the energy storage system. In our example, the cost of the system after using retired batteries is only about 61% of the cost of using new batteries, which suggests that utilizing retired batteries instead of new batteries has a better cost performance.

An image inpainting-based data augmentation method for improved sclerosed glomerular identification performance with the segmentation model EfficientNetB3-Unet

The percent global glomerulosclerosis is a key factor in determining the outcome of renal transfer surgery. At present, the rate is typically computed by pathologists, which is labour intensive and nonstandardized. With the development of Deep Learning (DL), DL-based segmentation models can be used to better identify and segment normal and sclerosed glomeruli. Based on this, we can better quantify percent global glomerulosclerosis to reduce the discard rate of donor kidneys. We used 51 whole slide images (WSIs) from different institutions that are publicly available on the internet. However, the number of sclerosed glomeruli is much smaller than that of normal glomeruli in different WSIs, which can reduce the effectiveness of Deep Learning. For better sclerosed glomerular identification and segmentation performance, we modified and trained a GAN (generative adversarial network)-based image inpainting model to obtain more synthetic sclerosed glomeruli. Our proposed inpainting method achieved an average SSIM (Structural Similarity) of 0.8086 and an average PSNR (Peak Signal-to-Noise Ratio) of 22.8943 dB in the area of generated sclerosed glomeruli. We obtained sclerosed glomerular segmentation performance improvement by adding synthetic sclerosed glomerular images and achieved the best Dice of glomerular segmentation in different test sets based on the modified Unet model.

RT-Ranked: Towards Network Resiliency by Anticipating Demand in TSCH/RPL Communication Environments

Time-slotted Channel Hopping (TSCH) Media Access Control (MAC) was specified to target the Industrial Internet of Things needs. This MAC balances energy, bandwidth, and latency for deterministic communications in unreliable wireless environments. Building a distributed or autonomous TSCH schedule is arduous because the node negotiates cells with its neighbours based on queue occupancy, latency, and consumption metrics. The Minimal TSCH Configuration defined by RFC 8180 was specified for bootstrapping a 6TiSCH network and detailed configurations necessary to be supported. In particular, it adopts Routing Protocol for Low Power and Lossy networks (RPL) Non-Storing mode, which reduces the node’s network awareness. Dealing with unpredicted traffic far from the forwarding node is difficult due to limited network information. Anticipating this unexpected flow from multiple network regions is essential because it can turn the forwarding node into a network bottleneck leading to high latency, packet discard or disconnection rates, forcing RPL to change the topology. To cope with that, this work proposes a new mechanism that implements an RPL control message option for passing forward the node’s cell demand, allowing the node to anticipate the proper cell allocation for supporting the traffic originating by nodes far from the forwarding point embedded in Destination-Oriented Directed Acyclic Graph (DODAG) Information Object (DIO) and Destination Advertisement Object (DAO) RPL control messages. Implementing this mechanism in a distributed TSCH Scheduling developed in Contiki-NG yielded promising results in supporting unforeseen traffic bursts and has the potential to significantly improve the performance and reliability of TSCH schedules in challenging network environments.

Blood Component Usage and Discard in the Blood Centre of a Tertiary Care Hospital in a Remote Part of North-east India: A Cross-sectional Study

Introduction: Blood and its various components are valuable resources for sustaining life. They are routinely used and form an integral part of patient care. The judicious use of blood and its components is necessary in low socio-economic countries. Aim: To estimate the usage of blood and blood components and its discard in a tertiary care hospital. Materials and Methods: A hospital-based retrospective cross- sectional study was conducted in the Blood Centre, Diphu Medical College and Hospital, Karbi Anglong, Assam, India. Data was retrieved from Blood Centre registers over a period of 12 month, from July 2021 to June 2022. Both replacement and voluntary donors were selected based on donor selection criteria. All collected blood units were stored and subsequently subjected to Transfusion Transmitted Infections (TTI) testing. The data was tabulated using Microsoft Excel sheet. Results: During the study period, a total of 4,525 units of whole blood were collected, and 7,539 blood units, including both whole blood and blood components, were prepared. The highest number of issues during the period comprised of whole blood at 2,468 units. Among blood components, 1,854 units of Packed Red Blood Cells (PRBCs) were most commonly utilised, followed by 1,824 units of Fresh Frozen Plasma (FFP). A total of 334 units (4.43%) of blood/ blood components were discarded due to various reasons, with the highest discard rate observed for Platelet Concentrates (PC) at 71 (6.28%) units. The major reason for discard was seropositivity, accounting for 212 (63.5%) units. Conclusion: Adequate blood inventory, along with proper training and sensitisation of hospital staff, should be conducted at timely intervals regarding proper donor selection, collection, and storage of blood/ blood products. Clinicians should also be engaged to optimise the usage of blood/ blood products. These steps can help minimise wastage in resource limited countries.

Medical and economic impacts of managing corneas from older donors at the tissue bank-a single-center retrospective study spanning over 12 years.

To evaluate the impact of corneas from donors over 80 years of age on the activity of the North of France Tissue Bank and to determine the potential cost implications for banks using corneas from older donors. We analyzed data from a single-center retrospective cohort study of 6,023 corneas preserved at the Lille Tissue Bank between 2012 and 2023. Donors, unrestricted by age, were divided into two groups: younger (≤ 80 years) and older (> 80 years). Corneas were categorized based on endothelial cell density (ECD). Data were collected from patients who underwent corneal transplantation. A financial impact model was created to assess the effects of using corneas from different age groups on the overall benefits of corneal transplant procedures. The average donor age was 67.5 ± 14.5 years. The median age of donors gradually increased from 66 to 73 years over the 12-year study period, with donors over 80 years old representing more than 24% since 2021. Corneas from older donors had a higher discard rate (62.53% vs. 39.66%) due to poor endothelial quality and serological concerns (both p < 0.0001). Additionally, these corneas had lower ECD, with a larger proportion deemed unsuitable for grafting due to low ECD (30% vs. 8.2%). Corneas from younger donors were more often used for endothelial transplants, which require higher ECD. The mean economic benefit per cornea showed a moderate negative correlation with donor age. The net benefit of corneal transplants decreased as the proportion of donors aged over 80 years increased. It is predicted that a net benefit of zero would be attained when the proportion of donors over 80 years is 44.4%. Using corneas from donors over 80 years of age can help alleviate the shortage of donor tissue and be effective if certain quality standards are met. However, additional costs incurred by eye banks must be factored into this equation.

Future Blood Debt: Projecting Blood Supply and Demand of Korea Based on Subnational Population Projections (2021-2050).

South Korea faces a critical challenge with its rapidly declining fertility rates and an increasingly aging population, which significantly impacts the country's blood supply and demand. Despite these nationwide trends, regional disparities in blood supply and demand have not been thoroughly studied. This research utilized blood donation data from the Korean Red Cross and blood transfusion data from the Health Insurance Review and Assessment Service. We analyzed these datasets in conjunction with regional population projections to simulate blood supply and demand from 2021 to 2050 across South Korea. Sensitivity analyses were conducted to assess the impact of various factors, including the number of donors, age eligibility criteria for donations, frequency of donations, and blood discard rates. Our projections indicate a decreasing trend in blood supply, from 2.6 million units in 2021 to 1.4 million units by 2050, while demand is expected to peak at 5.1 million units by 2045 before declining. Metropolitan areas, particularly Gyeonggi Province, are projected to experience the most severe shortages. Sensitivity analyses suggest that increasing the donation frequency of existing donors and relaxing age eligibility criteria are more effective strategies in addressing these imbalances than merely increasing the number of new donors. Blood discard rates showed minimal impact on the overall blood shortage. The findings emphasize the urgent need for targeted strategies to mitigate national and regional blood supply shortages in South Korea. Encouraging frequent donations from experienced donors and broadening eligibility criteria are critical steps toward stabilizing the blood supply amidst demographic shifts. These strategies must be prioritized to address the impending regional disparities in blood availability.

Impact of cleanroom status on the reasons for discarding organ-cultured corneal transplants in a modern eye bank - More donor corneas thanks to astronaut suit?

This study investigated the influence of cleanroom conditions on the discard rates of donor corneas in a German university eye bank. Discard rates were analysed from 2017 to 2020 at the LIONS Cornea Bank at Saarland University Medical Center. 1941 corneas from 971 donors were included. 1262 corneas (65.1%) were stored in a class D cleanroom from 2017 to 2019 and processed in a cleanroom class A sterile bank (group 1). 679 corneas (34.9%) were continuously stored in a class B cleanroom and processed in a class A cleanroom safety cabinet in the same room from 2019 to 2020 (group 2). The target parameter of this work was the number of contamination-related discards. Although they cannot be influenced by the spatial conditions, the discards due to insufficient endothelial quality, serology, contraindications, scars and technical causes were also recorded. Statistical analysis was performed using SPSS and various testing procedures. In group 1, significantly more corneas were discarded due to positive serology (6.9%|3.8%, p = 0.020). There was no significant change between both groups for either contamination or the other reasons for discard. Optimization of hygiene standards from cleanroom class D to B did not reduce contamination. Serology, endothelial quality, medical contraindications and the presence of scars cannot be influenced by cleanroom conditions.

Exploring the Role of Intraoperative Positive Culture of Allograft Bone in Subsequent Postoperative Infections among Donors and Recipients in Bone Bank Processing.

Allografts have been frequently used in orthopedic procedures. The purposes of this study were to evaluate the discard rates and bacterial contamination of a bone bank, and to assess the clinical outcomes of recipients with bacterial culture-positive donor allografts. We retrospectively reviewed 1764 allografts which were harvested from living donors and stored in a bone bank from 2018 to 2022. The donors whose allografts displayed bacterial contamination at retrieval of the primary hip or knee arthroplasty were followed for microbiology and subsequent prosthetic joint infection analysis. The infected pathogens, antibiotic treatment and subsequent infection were reviewed for the intraoperative positive culture group. The discard rate was 17%, and the bacterial contamination rate of bone retrieval was 2.15%. Thirty-eight allografts at retrieval displayed confirmed bacterial growth, and 37 patients did not reveal infective signs at 6 months follow-up. A total of 1464 allografts were stored and implanted, among which 28 allografts (1.91%) were confirmed to be positive for bacterial growth and 13 cases (0.89%) were confirmed as surgical site infections. Our results validate the suggestion that our bone bank system performs good quality monitoring to eliminate the risk of dissemination of viral and bacterial diseases and to decrease surgical site infection after allograft implantation. By ensuring aseptic conditions and contamination-reducing strategies during harvesting and thawing, the allografts can be safely stored and implanted while limiting bacterial contamination. Our findings confirm that the intraoperative positive cultures of allografts did not contribute to subsequent postoperative surgical site infection in donors and recipients.

Preloaded DMEK with endo-in technique: Standardizing and minimizing the learning curve over 5 years using 599 corneal tissues.

To report the outcomes of standardizing pre-loaded DMEK with endothelium-inwards and its associated learning curve. Between 2017 and 2021, a total of 599 tissues were stripped using 'trephine and strip' method and loaded by folding the tissue as a taco-fold with endothelium-inwards. The folded tissues were pulled inside the funnel of a 2.2 mm IOL cartridge and stored for the desired number of days in organ culture media supplemented with dextran. Donor characteristics, endothelial cell loss (ECL) and mortality assessed by trypan blue positivity before and after stripping, and eventful cases during stripping/loading were recorded. The tissues found unsuitable for transplant after stripping (6.7%) were significantly higher compared with loading (0.67%). Central or peripheral tears, fragility of the tissues, and insufficient endothelial cell density mainly attributed towards the discard rate. Mean ECL from pre-stripping to post-stripping was 0.27% with endothelial cell mortality of 0.64% at the end of stripping. Cumulative endothelial mortality fold change (pre-strip to post-strip) was high in the first two years of operation (18.9%), which reduced to 5.1% in the following three years with significant difference (p = 0.0352). Average tissue wastage (3 operators) from first 1-150 tissues was 3%, which significantly reduced to 0.9% after achieving the learning curve (151-250) (p = 0.0492). DMEK graft preparation requires a learning curve. However, an operator with DMEK stripping skills can easily adapt to pre-loading a DMEK graft in endothelium-inwards fashion with minimal learning curve.

Later Brain Death Declaration Correlates to Favorable Donor Characteristics but Decreased Heart Acceptance.

With rates of potential donor heart discard as high as 66% nationally, quality improvement efforts must seek to optimize donor utilization. Whether the timing of donor brain death declaration (BDD) influences organ acceptance is understudied. The authors sought to characterize the impacts of time between donor hospital admission and BDD on heart utilization and posttransplant outcomes. All potential heart donors and recipients in the United Network for Organ Sharing database were identified (2006-2021). Admission-to-BDD cohorts were: 1 to 2 d (n = 52 469), 3 to 4 d (n = 44 033), 5 to 7 d (n = 24 509), and 8 to 10 d (n = 8576). Donor clinical characteristics were compared between cohorts, and donor acceptance was assessed using multivariable binary logistic regression. Recipient posttransplant survival was assessed with the Kaplan-Meier method. Donor demographics and comorbidity profiles (diabetes and hypertension) were comparable across cohorts. Anoxia/overdose deaths were more common (10% > 21% > 24% > 18%, respectively) and cardiopulmonary resuscitation requirements were higher (37% > 52% > 58% > 47%) when BDD occurred longer after admission. Renal dysfunction (44% > 44% > 35% > 29%) and inotrope requirements (52% > 25% > 36% > 29%) were lower in the later BDD cohorts. Proportions of hepatic dysfunction (18%-21%) and left ventricular ejection fraction <50% (13%-16%) were clinically equivalent. Donor acceptance differed by admission-to-BDD cohort (36% [1-2 d], 34% [3-4 d], 30% [5-7 d], and 28% [8-10 d]). Admission-to-BDD >4 d was independently associated with lower odds of acceptance on multivariable analysis (odds ratio 0.79, P < 0.001). Recipients experienced equivalent posttransplant survival for all donor admission-to-BDD cohorts ( P = 0.999 adults and P = 0.260 pediatrics). Heart donors with later BDD were disproportionately discarded despite similar-to-favorable overall clinical profiles, resulting in nearly 3000 fewer transplants during the study. Increased utilization of donors with later BDD and "high-risk" characteristics (eg, anoxia/overdose, cardiopulmonary resuscitation requirement) can improve rates of transplantation without compromising outcomes.

Impact of Deceased-donor Acute Kidney Injury on Kidney Transplantation.

Even as record numbers of deceased donors are undergoing organ recovery, the global transplant community continues to struggle with a shortage of donor organs and a high organ discard rate. Acute kidney injury (AKI) occurs in many hospitalized patients, including up to 25% of patients in critical condition. Registry studies have shown a significant increase in nonrecovery or organ discard rates in AKI donors, despite most studies reporting similar clinical outcomes compared with non-AKI donors. This review aims to capture the salient information learned from these studies and to summarize the efforts that have been made to gain a more granular understanding of how kidneys from donors with AKI behave posttransplant. In particular, we reviewed the studies that analyzed the clinical outcomes in different stages of AKI and AKI in marginal donors, such as kidney donor profile index of >85%, older donors, and donation after circulatory death donors. We summarized studies investigating molecular biomarkers, transcriptomics, and possible future therapeutic targets for postdonation AKI.

The role of Magellanic penguins (Spheniscus magellanicus) on landscape dynamics and lithic taphonomy in La Pastosa Islet, North Patagonia, Argentina

This study presents the results of a systematic survey of La Pastosa Islet, located 700 m off the west coast of Río Negro, Argentina. This small islet has the particularity of hosting the northernmost colony of Magellanic penguins ( Spheniscus magellanicus) to date and contains evidence of its use by hunter-gatherer groups during the late Holocene. This growing colony started around 2002 and has had a significant impact on the subsurface archeological record of the islet by increasing erosion and exposing buried materials through nest excavation, particularly lithic artifacts. The spatial analysis of the distribution of artifact and penguin burrows indicates that the actions of the latter generated a “snapshot” of the subsurface distribution of the lithic record. The observed distribution suggested higher discard rates at the center of the islet. Furthermore, this study shows the synergy between both types of records in the formation dynamics of the lithic landscape and the agency of penguins as active landscape engineers. Finally, the obtained results have important implications for the management of the protected sector of the recently established Islote Lobos National Park, within which the study area is located.

Preserved 2-y Liver Transplant Outcomes Following Simultaneous Thoracoabdominal DCD Organ Procurement Despite Effects on Liver Utilization Rate.

Current techniques for donation after circulatory determination of death (DCD) heart procurement, through either direct procurement and machine perfusion or thoracoabdominal normothermic regional perfusion (NRP), have demonstrated excellent heart transplant outcomes. However, the impact of thoracoabdominal DCD (TA-DCD) heart procurement on liver allograft outcomes and utilization is poorly understood. One hundred sixty simultaneous heart and liver DCD donors were identified using the United Network for Organ Sharing/Organ Procurement and Transplantation Network database between December 2019 and July 2021. Liver outcomes from TA-DCD donors were stratified by heart procurement technique and evaluated for organ utilization, graft survival, and patient survival. Results were compared with abdominal-only DCD (A-DCD; n = 1332) and donation after brain death (DBD; n = 12 891) liver transplants during the study interval. Kaplan-Meier methods with log-rank testing were used to evaluate patient and graft survival. One hundred thirty-three of 160 livers procured from TA-DCD donors proceeded to transplant. TA-DCD donors were younger (mean 28.26 y; P < 0.0001) with lower body mass index (mean 26.61; P < 0.0001) than A-DCD and DBD donors. TA-DCD livers had equivalent patient survival ( P = 0.893) and superior graft survival (P = 0.009) compared with A-DCD. TA-DCD livers had higher rates of organ discard for long warm ischemia time (37.0%) than A-DCD (20.5%) and DBD (0.5%; P < 0.0001), with direct procurement and machine perfusion procurements leading to a higher discard rate (18.5%) than NRP procurements (7.4%). Liver transplants after TA-DCD donation demonstrated equivalent patient outcomes and excellent graft outcomes. NRP procurements resulted in the lowest rate of organ discard after DCD donation and may represent an optimal strategy to maximize organ utilization.