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Recently, owing to abnormal climate caused by climate change, the frequency of heavy snow has increased, resulting in increased damage to horticultural facilities. Therefore, considering the characteristics of snow distribution, simulating the distribution of snow on the greenhouse is required. Additionally, because it is difficult to artificially design the experimental environment for measuring snow loads in the field experiment, a computer simulation technology approach is necessary as an alternative. In this study, the characteristics and distribution of snow on the greenhouse roof were identified through an artificial snow experiment, and a numerical analysis model was designed using the discrete element method (DEM). The designed model was verified through the results of artificial snow load tests. Using this validated model, the pressure distribution characteristics on the roof surface of the greenhouse for snow cover were analysed. Moreover, computational fluid dynamics (CFD) techniques was integrated to account for the impact of wind. According to the analysis results, the average load was highest at 59.33 Pa in the pitched-roof multi-span, and the maximum load was 193.62 Pa in the arched-roof multi-span greenhouse. CFD–DEM coupled model was developed to simulate the distribution of snow cover based on wind conditions. The simulation results revealed that the snow load on the leeward roof exhibited an increase compared to the windward roof. However, the snow load on the leeward roof tended to decrease as the wind speed increased. These simulation results could be utilised as a reference for greenhouse design standards. • Developed a DEM model simulating greenhouse snow distribution. • Achieved high validation (R2 > 0.96) with small-scale field experiments. • Coupled the DEM with a validated CFD model for commercial greenhouse assessment. • Demonstrated accurate snow load prediction within greenhouses using the CFD–DEM model. [ABSTRACT FROM AUTHOR]

In mechanically ventilated piglet houses, ventilation is considered the most important aspect that can enhance the rearing environment. However, the airflow rate of fans can be less than the design rate due to pressure losses caused by operating conditions. To ensure the accurate estimation of the airflow rate, pressure loss factors should be evaluated since they have a strong influence on ventilation. In this study, pressure losses were evaluated through field experiments with various inlet types (side window, ceiling slot), outlet types (side and chimney exhaust fan), and operating conditions (fan speed, inlet opening size). A fan airflow rate formula accounting for the characteristics of ventilation systems was developed based on the fan performance reported by the manufacturer (designed performance) and orifice theory. Compared with in-situ and design fan performance, the in-situ airflow rate reduced by an average of 7–35% due to pressure losses. The pressure loss of the chimney exhaust fan was higher than that of the side exhaust fan due to the long duct and the position of the fan. The ventilation rate for the ceiling slot inlet was prone to overestimation due to a higher resistance curve coefficient (0.4) than that of the side window inlet. The developed ventilation rate formula was validated using 360 cases and it showed high accuracy (side exhaust fan R 2 > 0.9947 , chimney exhaust fan R 2 > 0.9947). Thus, the evaluated pressure loss factors and the developed ventilation rate formula can be applied for the design of ventilation systems in piglet houses. • Evaluation of pressure loss factors according to ventilation system in piglet house. • In-situ fan perforamcnce estimated by design fan performance data. • Developing a ventilation rate equation using opening size, fan speed. [ABSTRACT FROM AUTHOR]

Introduction: Under the hypothesis that early natural killer cell infusion (NKI) following haploidentical stem cell transplantation (haplo-SCT) will reduce relapse in the early post-transplant period, we conducted a pilot study to evaluate the safety and feasibility of NKI following haplo-SCT in children with recurrent neuroblastoma who failed previous tandem high-dose chemotherapy and autologous SCT. Methods: We used the high-dose 131I-metaiodobenzylguanidine and cyclophosphamide/fludarabine/anti-thymocyte globulin regimen for conditioning and infused 3 × 107/kg of ex-vivo expanded NK cells derived from a haploidentical parent donor on days 2, 9, and 16 post-transplant. Interleukin-2 was administered (1 × 106 IU/m2/day) subcutaneously to activate infused donor NK cells on days 2, 4, 6, 9, 11, 13, 16, 18, and 20 post-transplant. Results: Seven children received a total of 19 NKIs, and NKI-related acute toxicities were fever (n = 4) followed by chills (n = 3) and hypertension (n = 3); all toxicities were tolerable. Grade ≥II acute GVHD and chronic GVHD developed in two and five patients, respectively. Higher amount of NK cell population was detected in peripheral blood until 60 days post-transplant than that in the reference cohort. Cytomegalovirus and BK virus reactivation occurred in all patients and Epstein-Barr virus in six patients. Six patients died of relapse/progression (n = 5) or treatment-related mortality (n = 1), and one patient remained alive. Conclusion: NKI following haplo-SCT was relatively safe and feasible in patients with recurrent neuroblastoma. Further studies to enhance the graft-versus-tumor effect without increasing GVHD are needed. [ABSTRACT FROM AUTHOR]

Purpose: We aimed to report our single-center experience of allogeneic hematopoietic cell transplantation (HCT), which has been the only curative option for certain patients with lethal primary immunodeficiencies (PIDs).Methods: We summarized the results of HCT performed for patients with PIDs for 11 consecutive years from 2006 to 2016 at Samsung Medical Center, Seoul, Korea. Twenty-six patients with PIDs received HCT. Most had chronic granulomatous disease (42.3%), Wiskott Aldrich syndrome (15.4%), or severe combined immunodeficiency (11.5%).Results: Nine patients (34.6%) received HCT during the former half period and 17 patients (65.4%) during the latter half period. Donor types were categorized as: matched sibling donor (n = 5), unrelated donor (n = 17), and familial mismatched donor (FMMD) (n = 4). Unrelated HCT and FMMD transplantation were increasingly performed in the latter half period compared to the first (5 vs. 16, P = 0.034). Five patients experienced initial engraftment failure, but all of them were eventually engrafted after additional HCTs. The 3-year probability of overall survival was 72.0%. Seven patients (26.9%) died, and the causes of death were bacterial sepsis (n = 4), pneumonia (n = 1), chronic graft-versus-host disease (GVHD) (n = 1), and diffuse alveolar hemorrhage (n = 1). Two patients with bacterial sepsis and a patient with pneumonia also had chronic GVHD. Unrelated HCT and use of methotrexate were associated with poor outcome. Complete chimerism was attained in 85.0% at 1 year after HCT.Conclusion: PID candidates have been increasingly identified for allogeneic HCT in Korea, and the majority of them could be cured by HCT. Establishment of a systematic registry of PID patients for HCT is needed. [ABSTRACT FROM AUTHOR]

Monosomal karyotype (MK) is known as a far end of the unfavorable cytogenetics in adult acute myeloid leukemia (AML), while available data in childhood AML is scarce. In this study, we investigated the prevalence and prognostic value of MK with retrospectively analyzed 119 patients newly diagnosed with childhood de novo AML. Ten patients (8.4%) revealed to have MK. All MK-positive (MK(+)) AML were associated with complex cytogenetic abnormalities and belonged to the cytogenetic adverse-risk group. Nine of MK(+) patients (90%) achieved complete remission. The event-free survival (EFS) and overall survival (OS) of MK(+) adverse group were comparable to the ESF and OS of MK-negative non-adverse group (EFS 60.0 ± 15.5% vs 59.0 ± 5.1%, P = 0.925; OS 70.0 ± 14.5% vs 58.1 ± 5.3%, P = 0.696). In multivariate analysis, MK was not an independent adverse prognostic factor for EFS (hazard ratio 0.45, 95% C.I. 0.13–1.50, P = 0.194). In addition, 7 of 9 MK(+) patients who received allogeneic hematopoietic stem cell transplantation (HSCT) survived event-free, with a median follow-up of 64 months. In conclusion, MK did not act as an adverse prognostic factor in childhood de novo AML. Allogeneic HSCT might have contributed to the excellent outcome of MK(+) childhood de novo AML. [ABSTRACT FROM AUTHOR]

We retrospectively analyzed infectious complications during tandem high-dose chemotherapy and autologous stem cell transplantation (HDCT/auto-SCT) in children and adolescents with high-risk or recurrent solid tumors. A total of 324 patients underwent their first HDCT/auto-SCT between October 2004 and September 2014, and 283 of them proceeded to their second HDCT/auto-SCT (a total of 607 HDCT/auto-SCTs). During the early transplant period of 607 HDCT/auto-SCTs (from the beginning of HDCT to day 30 post-transplant), bacteremia, urinary tract infection (UTI), respiratory virus infection, and varicella zoster virus (VZV) reactivation occurred in 7.1%, 2.3%, 13.0%, and 2.5% of HDCT/auto-SCTs, respectively. The early transplant period of the second HDCT/auto-SCT had infectious complications similar to the first HDCT/auto-SCT. During the late transplant period of HDCT/auto-SCT (from day 31 to 1 year post-transplant), bacteremia, UTI, and VZV reactivation occurred in 7.5%, 2.5%, and 3.9% of patients, respectively. Most infectious complications in the late transplant period occurred during the first 6 months post-transplant. There were no invasive fungal infections during the study period. Six patients died from infectious complications (4 from bacterial sepsis and 2 from respiratory virus infection). Our study suggests that infectious complications are similar following second and first HDCT/auto-SCT in children. [ABSTRACT FROM AUTHOR]

• The light intensity over 507 W ∙ m-2 did not have a significant effect on the transpiration rate increase. • The relationship between VPD and transpiration rate was expressed by Gauss peak fitting method. • Tomato transpiration model considering the specific environment in the greenhouse was developed. Since transpiration model of tomato is a main index for precise irrigation control in greenhouse soilless culture, more precise transpiration model needs to be developed for tomato cultivation. Although various models have been developed, they are limited under low VPD condition due to high light intensity in greenhouse, especially during the daytime at summer season of Korea. Therefore, the objective of this study was to develop an improved model considering the above unusual environment in greenhouse. Experiments were conducted between 2017 and 2018. The actual transpiration rate was measured by a load cell, weight measuring device, and used as data for model development. In 2018 experiment, an environment suitable for the growth of crops was established through shading film and humidification. The model equation was developed by calibrating parameters within the VPD range suitable for crop growth with compensated radiation under high light conditions. Experimental results showed that the transpiration rate had exponential increase to the maximum with respect to radiation and transpiration rate to VPD was fitted to gaussian peak shape. The developed model equation was verified by comparing with measured transpiration rate. Verification result showed that the developed model had a higher correlation coefficient than the existing one. In summary, a tomato transpiration model considering the specific environment in the greenhouse was developed in this study. It could be used to precision irrigation and environment control in greenhouse tomato cultivation. [ABSTRACT FROM AUTHOR]

The original version of this article unfortunately contained a mistake in the 7th author’s given name. The correct version is presented above. [ABSTRACT FROM AUTHOR]

A substantial reduction in the environmental impacts related to the construction and operation of agricultural buildings is needed to adapt to the continuing development of agriculture. The life cycle assessment (LCA) is a methodology used to quantify the environmental impact of different processes involved in the production and therefore has been increasingly applied to assess the environmental burden. However, most LCA-related research studies have focused on the overall environmental impact of the entire system without considering the energy load of the agricultural buildings. By integrating the LCA tool with other design tools such as the building energy simulation (BES), the identification of environmental hotspots and the mitigation options become possible during the design process. Thus, the objective of the paper was to identify the current integration approaches used to combine BES and LCA results to assess the environmental impact of different heating systems such as absorption heat pump (AHP) using energy from thermal effluent, electricity-powered heat pump and kerosene-powered boilers used in a conventional multi-span Korean greenhouse. The assessment result revealed that the environmental impact caused using a kerosene-powered boiler is largest in terms of the acidification potential (AP), global warming potential (GWP) and Eutrophication Potential (EP) of 1.15 × 100 kg SO2-eq, 1.13 × 102 kg CO2-eq and 1.62 × 10−1 kg PO4-eq, respectively. Detailed analysis of the result showed that the main contributor for greenhouse gas emission was caused by the type, amount and source of energy used to heat the greenhouse, which contributed to a maximum of 86.59% for case 1, 96.69% for case 2 and a maximum of 96.47% for case 3, depending on the type of greenhouse gas being considered. [ABSTRACT FROM AUTHOR]

The diagnosis of inherited platelet function disorders (IPFDs) is challenging owing to the unavailability of essential testing methods, including light transmission aggregometry and flow cytometry, in several medical centers in Korea. This study, conducted by the Korean Pediatric Hematology Oncology Group from March 2017 to December 2020, aimed to identify the causative genetic variants of IPFDs in Korean patients using next-generation sequencing (NGS). Targeted exome sequencing, followed by whole-genome sequencing, was performed for diagnosing IPFDs. Of the 11 unrelated patients with suspected IPFDs enrolled in this study, 10 patients and 2 of their family members were diagnosed with Glanzmann thrombasthenia (GT). The variant c.1913+5G>T of ITGB3 was the most common, followed by c.2333A>C (p.Gln778Pro) of ITGB2B. Known variants of GT, including c.917A>C (p.His306Pro) of ITGB3 and c.2975del (p.Glu992Glyfs*), c.257T>C (p.Leu86Pro), and c.1750C>T (p.Arg584*) of ITGA2B, were identified. Four novel variants of GT, c.1451G>T (p.Gly484Val) and c.1595G>T (p.Cys532Phe) of ITGB3 and c.1184G>T (p.Gly395Val) and c.2390del (p.Gly797Valfs*29) of ITGA2B, were revealed. The remaining patient was diagnosed with platelet type bleeding disorder 18 and harbored two novel RASGRP2 variants, c.1479dup (p.Arg494Alafs*54) and c.813+1G>A. We demonstrated the successful application of NGS for the accurate and differential diagnosis of heterogeneous IPFDs. [ABSTRACT FROM AUTHOR]

The role of unrelated donor HSCT for children with de novo AML in CR1 is controversial. We performed this study to investigate the feasibility of unrelated donor HSCT who initially had intermediate‐ or high‐risk cytogenetics. We retrospectively reviewed medical records of patients with AML who received unrelated HSCT in CR1 at Samsung Medical Center between November 2001 and January 2012. Patients were allocated based on karyotype at diagnosis as follows: (a) low‐risk: inv(16), t(16;16), t(8;21), and t(15;17); (b) high‐risk: ‐5, 5q‐, ‐7, 3q abnormalities, t(8;16), t(6;9), t(6;11), t(6;21), t(10;11), complex karyotype (≥3 abnormalities), and acute megakaryocytic leukemia without t(1;22); and (c) IR: all the other karyotypes including normal. Patients in intermediate‐ or high‐risk group who were transplanted with either unrelated CB or matched unrelated BM/mobilized PB in their CR1 were included in this study. The projected OS and EFS rates were 74.9% and 71.1%, respectively, with a median follow‐up of 87.3 months after transplantation. The EFS was 70.1%, 80.7%, and 73.9% for CB, BM, and mobilized PB groups, respectively (P = 0.89), and 73.9% and 70.6% for IR and high‐risk groups (P = 0.76). The leading cause of death was relapse (n = 8), and only one patient died from non‐relapse cause. Unrelated donor HSCT seems a feasible approach for children with intermediate‐ or high‐risk AML in CR1. Relapse remains the leading cause of treatment failure among these patients. [ABSTRACT FROM AUTHOR]