bluuebunny/crossref_metadata_2025_split huggingface dataset:
Meta-analysis of the effects of 1-methylcyclopropene (1-MCP) treatment on climacteric fruit ripening
Authors: Zhang Jing , Ma Yuanchun , Dong Chao , Terry Leon A. , Watkins Christopher B. , Yu Zhifang , Cheng Zong-Ming 
Published: December 2020

Abstract1-Methylcyclopropene (1-MCP) is an inhibitor of ethylene perception that is widely used to maintain the quality of several climacteric fruits during storage. A large body of literature now exists on the effects of 1-MCP on climacteric fruit ripening for different species and environmental conditions, presenting an opportunity to use meta-analysis to systematically dissect these effects. We classified 44 ripening indicators of climacteric fruits into five categories: physiology and biochemistry, quality, enzyme activity, color, and volatiles. Meta-analysis showed that 1-MCP treatment reduced 20 of the 44 indicators by a minimum of 22% and increased 6 indicators by at least 20%. These effects were associated with positive effects on delaying ripening and maintaining quality. Of the seven moderating variables, species, 1-MCP concentration, storage temperature and time had substantial impacts on the responses of fruit to 1-MCP treatment. Fruits from different species varied in their responses to 1-MCP, with the most pronounced responses observed in rosaceous fruits, especially apple, European pear fruits, and tropical fruits. The effect of gaseous 1-MCP was optimal at 1 μl/l, with a treatment time of 12–24 h, when the storage temperature was 0 °C for temperate fruits or 20 °C for tropical fruits, and when the shelf temperature was 20 °C, reflecting the majority of experimental approaches. These findings will help improve the efficacy of 1-MCP application during the storage of climacteric fruits, reduce fruit quality losses and increase commercial value.
Pathway engineering in yeast for synthesizing the complex polyketide bikaverin
Authors: Zhao Meng , Zhao Yu , Yao Mingdong , Iqbal Hala , Hu Qi , Liu Hong , Qiao Bin , Li Chun , Skovbjerg Christine A. S. , Nielsen Jens Christian , Nielsen Jens , Frandsen Rasmus J. N. , Yuan Yingjin , Boeke Jef D. 
Published: December 2020

AbstractFungal polyketides display remarkable structural diversity and bioactivity, and therefore the biosynthesis and engineering of this large class of molecules is therapeutically significant. Here, we successfully recode, construct and characterize the biosynthetic pathway of bikaverin, a tetracyclic polyketide with antibiotic, antifungal and anticancer properties, in S. cerevisiae. We use a green fluorescent protein (GFP) mapping strategy to identify the low expression of Bik1 (polyketide synthase) as a major bottleneck step in the pathway, and a promoter exchange strategy is used to increase expression of Bik1 and bikaverin titer. Then, we use an enzyme-fusion strategy to directly couple the monooxygenase (Bik2) and methyltransferase (Bik3) to efficiently channel intermediates between modifying enzymes, leading to an improved titer of bikaverin at 202.75 mg/L with flask fermentation (273-fold higher than the initial titer). This study demonstrates that the biosynthesis of complex fungal polyketides can be established and efficiently engineered in S. cerevisiae, highlighting the potential for natural product synthesis and large-scale fermentation in yeast.
Docking of acetyl-CoA carboxylase to the plastid envelope membrane attenuates fatty acid production in plants
Authors: Ye Yajin , Nikovics Krisztina , To Alexandra , Lepiniec Loïc , Fedosejevs Eric T. , Van Doren Steven R. , Baud Sébastien , Thelen Jay J. 
Published: December 2020

AbstractIn plants, light-dependent activation of de novo fatty acid synthesis (FAS) is partially mediated by acetyl-CoA carboxylase (ACCase), the first committed step for this pathway. However, it is not fully understood how plants control light-dependent FAS regulation to meet the cellular demand for acyl chains. We report here the identification of a gene family encoding for three small plastidial proteins of the envelope membrane that interact with the α-carboxyltransferase (α-CT) subunit of ACCase and participate in an original mechanism restraining FAS in the light. Light enhances the interaction between carboxyltransferase interactors (CTIs) and α-CT, which in turn attenuates carbon flux into FAS. Knockouts for CTI exhibit higher rates of FAS and marked increase in absolute triacylglycerol levels in leaves, more than 4-fold higher than in wild-type plants. Furthermore, WRINKLED1, a master transcriptional regulator of FAS, positively regulates CTI1 expression by direct binding to its promoter. This study reveals that in addition to light-dependent activation, “envelope docking” of ACCase permits fine-tuning of fatty acid supply during the plant life cycle.
Glacial heterogeneity in Southern Ocean carbon storage abated by fast South Indian deglacial carbon release
Authors: Gottschalk Julia , Michel Elisabeth , Thöle Lena M. , Studer Anja S. , Hasenfratz Adam P. , Schmid Nicole , Butzin Martin , Mazaud Alain , Martínez-García Alfredo , Szidat Sönke , Jaccard Samuel L. 
Published: December 2020

AbstractPast changes in ocean 14C disequilibria have been suggested to reflect the Southern Ocean control on global exogenic carbon cycling. Yet, the volumetric extent of the glacial carbon pool and the deglacial mechanisms contributing to release remineralized carbon, particularly from regions with enhanced mixing today, remain insufficiently constrained. Here, we reconstruct the deglacial ventilation history of the South Indian upwelling hotspot near Kerguelen Island, using high-resolution 14C-dating of smaller-than-conventional foraminiferal samples and multi-proxy deep-ocean oxygen estimates. We find marked regional differences in Southern Ocean overturning with distinct South Indian fingerprints on (early de-)glacial atmospheric CO2 change. The dissipation of this heterogeneity commenced 14.6 kyr ago, signaling the onset of modern-like, strong South Indian Ocean upwelling, likely promoted by rejuvenated Atlantic overturning. Our findings highlight the South Indian Ocean’s capacity to influence atmospheric CO2 levels and amplify the impacts of inter-hemispheric climate variability on global carbon cycling within centuries and millennia.
Polycrystalline Ni nanotubes under compression: a molecular dynamics study
Authors: Rojas-Nunez J. , Baltazar S. E. , Gonzalez R. I. , Bringa E. M. , Allende S. , Kiwi M. , Valencia F. J. 
Published: December 2020

AbstractMechanical properties of nanomaterials, such as nanowires and nanotubes, are an important feature for the design of novel electromechanical nano-architectures. Since grain boundary structures and surface modifications can be used as a route to modify nanostructured materials, it is of interest to understand how they affect material strength and plasticity. We report large-scale atomistic simulations to determine the mechanical response of nickel nanowires and nanotubes subject to uniaxial compression. Our results suggest that the incorporation of nanocrystalline structure allows completely flexible deformation, in sharp contrast with single crystals. While crystalline structures at high compression are dominated by dislocation pinning and the multiplication of highly localized shear regions, in nanocrystalline systems the dislocation distribution is significantly more homogeneous. Therefore, for large compressions (large strains) coiling instead of bulging is the dominant deformation mode. Additionally, it is observed that nanotubes with only 70% of the nanowire mass but of the same diameter, exhibit similar mechanical behavior up to 0.3 strain. Our results are useful for the design of new flexible and light-weight metamaterials, when highly deformable struts are required.
Early prediction of neoadjuvant chemotherapy response for advanced breast cancer using PET/MRI image deep learning
Authors: Choi Joon Ho , Kim Hyun-Ah , Kim Wook , Lim Ilhan , Lee Inki , Byun Byung Hyun , Noh Woo Chul , Seong Min-Ki , Lee Seung-Sook , Kim Byung Il , Choi Chang Woon , Lim Sang Moo , Woo Sang-Keun 
Published: December 2020

AbstractThis study aimed to investigate the predictive efficacy of positron emission tomography/computed tomography (PET/CT) and magnetic resonance imaging (MRI) for the pathological response of advanced breast cancer to neoadjuvant chemotherapy (NAC). The breast PET/MRI image deep learning model was introduced and compared with the conventional methods. PET/CT and MRI parameters were evaluated before and after the first NAC cycle in patients with advanced breast cancer [n = 56; all women; median age, 49 (range 26–66) years]. The maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) were obtained with the corresponding baseline values (SUV0, MTV0, and TLG0, respectively) and interim PET images (SUV1, MTV1, and TLG1, respectively). Mean apparent diffusion coefficients were obtained from baseline and interim diffusion MR images (ADC0 and ADC1, respectively). The differences between the baseline and interim parameters were measured (ΔSUV, ΔMTV, ΔTLG, and ΔADC). Subgroup analysis was performed for the HER2-negative and triple-negative groups. Datasets for convolutional neural network (CNN), assigned as training (80%) and test datasets (20%), were cropped from the baseline (PET0, MRI0) and interim (PET1, MRI1) images. Histopathologic responses were assessed using the Miller and Payne system, after three cycles of chemotherapy. Receiver operating characteristic curve analysis was used to assess the performance of the differentiating responders and non-responders. There were six responders (11%) and 50 non-responders (89%). The area under the curve (AUC) was the highest for ΔSUV at 0.805 (95% CI 0.677–0.899). The AUC was the highest for ΔSUV at 0.879 (95% CI 0.722–0.965) for the HER2-negative subtype. AUC improved following CNN application (SUV0:PET0 = 0.652:0.886, SUV1:PET1 = 0.687:0.980, and ADC1:MRI1 = 0.537:0.701), except for ADC0 (ADC0:MRI0 = 0.703:0.602). PET/MRI image deep learning model can predict pathological responses to NAC in patients with advanced breast cancer.
Evaluation of the relationship between glaucomatous disc subtypes and occurrence of disc hemorrhage and glaucoma progression in open angle glaucoma
Authors: Yamagami Akiko , Tomidokoro Astuo , Matsumoto Shun , Yamazaki Yoshio , Yoshikawa Keiji , Yamagami Junkichi , Tomita Goji , Araie Makoto 
Published: December 2020

AbstractTo compare the occurrence of disc hemorrhages (DH) and glaucoma progression in open-angle glaucoma (OAG) patients with different glaucomatous disc types. Prospective, hospital-based, observational cohort study. OAG patients examined between 2000 and 2005, whose discs were classified as typical myopic glaucomatous (MG), generalized enlargement of cup (GE), or focal glaucomatous (FG) disc type were included and followed for 5 years. The first occurrence of DH during follow-up was analyzed using Kaplan–Meier analysis and difference in DH occurrence based on glaucomatous disc type using the Cox proportional-hazards model to adjust for effects of confounding factors. For inter-group comparison of glaucoma progression, the change rate of the mean deviation, Collaborative Initial Glaucoma Treatment Study scores, and fundus photographs were used. Thirty-nine patients with MG-, 18 with FG-, and 17 with GE-disc types were included. No significant inter-group difference was seen in the rate of glaucoma progression. The five-year probability of DH occurrence was much lower with MG- than with FG- or GE-disc types (P < 0.0220). The central corneal thickness (P = 0.0024) and mean intraocular pressure and its variations (P = 0.0450, 0.0219) contributed to DH occurrence. The MG-disc type demonstrated a much lower DH occurrence during follow-up than other disc types.
Serum angiopoietin-like 3 levels are elevated in obese non diabetic men but are unaffected during an oral glucose tolerance test
Authors: Garcés Maria Fernanda , Buell-Acosta Julieth Daniela , Rodríguez-Navarro Haiver Antonio , Pulido-Sánchez Estefania , Rincon-Ramírez Juan José , Moreno-Ordóñez Diana Carolina , Franco-Vega Roberto , Roncancio-Muñoz Jhoan Sebastian , Burgos-Cardenas Alvaro Javier , Lacunza Ezequiel , Castaño Justo P. , Diéguez Carlos , Nogueiras Rubén , Sanchez Elizabeth , Caminos Jorge Eduardo 
Published: December 2020

AbstractThis study aimed to determine ANGPTL3 serum levels in healthy young lean and obese non-diabetic men during an oral glucose tolerance test (OGTT) and correlate them with anthropometric, biochemical and hormonal parameters. A case–control study was carried out and 30 young obese non-diabetic (23.90 ± 3.84 years and BMI 37.92 ± 4.85 kg/m2) and 28 age-matched healthy lean (24.56 ± 3.50 years and BMI of 22.10 ± 1.72 kg/m2) men were included in this study. The primary outcome measures were serum basal ANGPTL3 and ANGPTL3–area under the curve (AUC) levels. The percentage of body fat was measured by dual-energy X-ray absorptiometry and biochemical, hormonal and insulin resistance indices were determined. Basal ANGPTL3 and ANGPTL3–AUC levels were significantly elevated (p < 0.05) in young obese subjects compared with lean subjects and were positively and significantly associated with different anthropometric measurements. Fasting ANGPTL3 serum levels were positively correlated with fasting insulin, leptin, Leptin/Adiponectin index and triglyceride—glucose index. Moreover, ANGPTL3–AUC was negatively correlated with Matsuda index. In this regard, chronically high ANGPTL3 levels in young obese subjects might favor triglyceride-rich lipoprotein clearance to replenish triglyceride stores by white adipose tissue rather than oxidative tissues.
Incisional hernia after surgical correction of abdominal congenital anomalies in infants: a systematic review with meta-analysis
Authors: Eeftinck Schattenkerk Laurens D. , Musters Gijsbert D. , Nijssen David J. , de Jonge Wouter J. , de Vries Ralph , van Heurn L. W. Ernest , Derikx Joep PM. 
Published: December 2020

AbstractIncisional hernia (IH) in children could result in life-threatening complications, including incarceration and bowel strangulation. The incidence and risk factors of IH in infants are scarcely reported. Since IH-correction may require extensive surgery and a long recovery program, identifying infants and birth defects at risk, may lead to a different approach during the primary surgery. Therefore, the aim of this review is to systematically review the available data on the incidence of IH following surgery for congenital anomalies in infants. All studies describing IH were considered eligible. PubMed and Embase were searched and risk of bias was assessed. Primary outcome was the incidence of IH, secondary outcomes were difference in IH occurrence between disease severity (complex vs simple) and closure method (SILO vs primary closure) in gastroschisis patients. A meta-analysis was performed to pool the reported incidences in total and per congenital anomaly separately. Subgroup analysis within gastroschisis articles was performed. The 50 included studies represent 3140 patients. The pooled proportion of IH was 0.03 (95% CI 0.02–0.05; I2 = 79%, p ≤ 0.01) all anomalies combined. Gastroschisis (GS) reported highest pooled proportion 0.10 (95% CI 0.06–0.17; n = 142/1273; I2 = 86%; p ≤ 0.01). SILO closure (OR 3.09) and simple gastroschisis, i.e. without additional anomalies, (OR 0.18) were of significant influence. This review reports the incidence of IH in infants with different congenital abdominal anomalies, of which gastroschisis reported the highest risk. In GS patients, complex GS and SILO closure are risk factors for IH development.
Quantification and epigenetic evaluation of the residual pool of hepatitis B covalently closed circular DNA in long-term nucleoside analogue-treated patients
Authors: Lebossé Fanny , Inchauspé Aurore , Locatelli Maëlle , Miaglia Clothilde , Diederichs Audrey , Fresquet Judith , Chapus Fleur , Hamed Kamal , Testoni Barbara , Zoulim Fabien 
Published: December 2020

AbstractHepatitis B virus (HBV) covalently closed circular (ccc)DNA is the key genomic form responsible for viral persistence and virological relapse after treatment withdrawal. The assessment of residual intrahepatic cccDNA levels and activity after long-term nucleos(t)ide analogues therapy still represents a technical challenge. Quantitative (q)PCR, rolling circle amplification (RCA) and droplet digital (dd)PCR assays were used to quantify residual intrahepatic cccDNA in liver biopsies from 56 chronically HBV infected patients after 3 to 5 years of telbivudine treatment. Activity of residual cccDNA was evaluated by quantifying 3.5 kB HBV RNA (preC/pgRNA) and by assessing cccDNA-associated histone tails post-transcriptional modifications (PTMs) by micro-chromatin immunoprecipitation. Long-term telbivudine treatment resulted in serum HBV DNA suppression, with most of the patients reaching undetectable levels. Despite 38 out of 56 patients had undetectable cccDNA when assessed by qPCR, RCA and ddPCR assays detected cccDNA in all-but-one negative samples. Low preC/pgRNA level in telbivudine-treated samples was associated with enrichment for cccDNA histone PTMs related to repressed transcription. No difference in cccDNA levels was found according to serum viral markers evolution. This panel of cccDNA evaluation techniques should provide an added value for the new proof-of-concept clinical trials aiming at a functional cure of chronic hepatitis B.
On the possibility of using temperature to aid in thyroid nodule investigation
Authors: Damião C. P. , Montero J. R. G. , Moran M. B. H. , da Cruz Filho R. A. , Fontes C. A. P. , Lima G. A. B. , Conci A. 
Published: December 2020

AbstractThyroid nodules are common, and their investigation is very important to exclude the possibility of cancer. The increase in blood vessels of malignant tumours may be related to local temperature augmentation detectable on the skin surface. The objective of this paper is to evaluate the feasibility of Infrared Thermography for cancer identification. For this purpose, two studies were performed. One used numerical modelling to simulate regional metabolic temperature propagation to evaluate whether a nodule is perceptible on the skin surface. A second study considered thyroid nodule identification by using convolutional neural networks (CNNs). First, variations in nodular size and fat thickness were investigated, showing that the fat layer has an important role in regional heat transfer. In the second study, the training process achieved accuracy of 96% for in-sample and 95% for validation. In the testing phase, 92% accuracy, 100% precision and 80% recall were achieved. Thus, the presented studies suggest the feasibility of using Infrared Thermography with the CNN Artificial Intelligence technique as additional information in the investigation of thyroid nodules for patients without a very thick subcutaneous fat layer.
Forecasting the long-term trend of COVID-19 epidemic using a dynamic model
Authors: Sun Jichao , Chen Xi , Zhang Ziheng , Lai Shengzhang , Zhao Bo , Liu Hualuo , Wang Shuojia , Huan Wenjing , Zhao Ruihui , Ng Man Tat Alexander , Zheng Yefeng 
Published: December 2020

AbstractThe current outbreak of coronavirus disease 2019 (COVID-19) has recently been declared as a pandemic and spread over 200 countries and territories. Forecasting the long-term trend of the COVID-19 epidemic can help health authorities determine the transmission characteristics of the virus and take appropriate prevention and control strategies beforehand. Previous studies that solely applied traditional epidemic models or machine learning models were subject to underfitting or overfitting problems. We propose a new model named Dynamic-Susceptible-Exposed-Infective-Quarantined (D-SEIQ), by making appropriate modifications of the Susceptible-Exposed-Infective-Recovered (SEIR) model and integrating machine learning based parameter optimization under epidemiological rational constraints. We used the model to predict the long-term reported cumulative numbers of COVID-19 cases in China from January 27, 2020. We evaluated our model on officially reported confirmed cases from three different regions in China, and the results proved the effectiveness of our model in terms of simulating and predicting the trend of the COVID-19 outbreak. In China-Excluding-Hubei area within 7 days after the first public report, our model successfully and accurately predicted the long trend up to 40 days and the exact date of the outbreak peak. The predicted cumulative number (12,506) by March 10, 2020, was only 3·8% different from the actual number (13,005). The parameters obtained by our model proved the effectiveness of prevention and intervention strategies on epidemic control in China. The prediction results for five other countries suggested the external validity of our model. The integrated approach of epidemic and machine learning models could accurately forecast the long-term trend of the COVID-19 outbreak. The model parameters also provided insights into the analysis of COVID-19 transmission and the effectiveness of interventions in China.
Production of a toxic polypeptide as a fusion inside GroEL cavity
Authors: Yurkova Maria S. , Sadykhov Elchin G. , Fedorov Alexey N. 
Published: December 2020

AbstractThe system is developed for efficient biosynthetic production of difficult-to-express polypeptides. A target polypeptide is produced fused into T. thermophilus GroEL chaperonin polypeptide chain in such a way that it is presented inside the GroEL cavity near the substrate binding surface. Such presentation allows alleviating potential problems of instability, toxicity or hydrophobicity of the fused peptide. Thermostability of thermophilic GroEL can be used for its one-step separation from the host cell proteins by heating. The target polypeptide may be released by any of amino acid-specific chemical treatments. In this study, GroEL was adapted for methionine-specific cleavage with cyanogen bromide by total replacement of methionine residues to facilitate further purification of the target polypeptide. The procedure is simple, robust and easy to scale-up. The capacity of this system to produce difficult-to-express polypeptides is demonstrated by production in bacterial system of one of the most potent antibacterial peptides polyphemusin I.
Effects of nickel content on the microstructure, microhardness and corrosion behavior of high-entropy AlCoCrFeNix alloys
Authors: López Ríos M. , Socorro Perdomo P. P. , Voiculescu I. , Geanta V. , Crăciun V. , Boerasu I. , Mirza Rosca J. C. 
Published: December 2020

AbstractIn this study the effect of three different nickel concentration on the microstructure, hardness and corrosion properties of high entropy alloys (HEAs) from AlCrFeCoNi system as an alternative material for medical instruments fabrication was investigated. The analyzed HEAs were AlCrFeCoNix obtained by vacuum arc remelting from high purity raw materials and having nickel atomic ratio x = 1.0, 1.4 and 1.8. The microscopy examination revealed the dendritic morphology for the reference alloy (AlCrFeCoNi) and that the extent of the interdendritic areas increased with the concentration of nickel while Cr was more segregated in the interdendritic areas than in dendrites. Hardness values decreased as the percentage of nickel increased due to the dissolution of the precipitates in a nickel-rich matrix and consequently the formation of continuous solid solutions. The corrosion properties of the synthesized HEAs were evaluated using a potentiodynamic polarization method. The alloys were immersed in Simulated Body Fluid during one week and the corrosion parameters were recorded. The low corrosion rates, low corrosion currents and high polarization resistance attest the good stability of these HEAs in simulated biological environment indicating their possible use for surgical and dental instruments.