bluuebunny/crossref_metadata_2025 huggingface dataset:
Nitrogen Partitioning in Young “Julyprince” Peach Trees Grown with Different Irrigation and Fertilization Practices in the Southeastern United States
Authors: Casamali Bruno , van Iersel Marc W. , Chavez Dario J.
Published: February 2021

Fertilizer recommendations for peach cultivation in the southeastern United States were developed decades ago and may not reflect the peach trees’ needs under current cultivation practices. Adequate fertilization for young peach trees induces a balanced vegetative/reproductive growth, ensures efficient resource use, and is environmentally sound. Droughts in the region are becoming more common. Supplemental irrigation for peaches from the time of field establishment serves as insurance in case drought conditions occur and can increase/advance the yield of young peach trees. Our objective was to determine the influence of different fertilizer levels (25, 50, 100, and 200% of the recommended rate), irrigation levels (irrigated vs. non-irrigated), and irrigation systems (drip vs. micro-sprinkler) on nitrogen partitioning and concentration in different organs of young peach trees. The cumulative nitrogen (N) removal per tree was not affected by the different fertilizer levels. Most of the N allocation was accounted for by summer pruning and defoliation (68% of the total N removed). Irrigated trees had higher cumulative N removal after three years than non-irrigated trees, with differences between irrigated vs. non-irrigated trees in most vegetative removal events (winter and summer pruning, and defoliation). Drip-irrigated trees had higher cumulative N removal after three years than micro-sprinkler-irrigated tress, with differences in N removal found in vegetative and reproductive removal events. Differences in N removal were mainly driven by differences in dry weight rather than the N concentration of the organs. These results suggest that different fertilizer levels did not alter the N partitioning in young peach trees, indicating that reduction in fertilizer applications can be done without negative effects. Furthermore, irrigation induced greater vegetative growth, especially under drought conditions, which may result in greater canopy volume and fruit yield compared to non-irrigated trees. Differences between irrigation systems are not consistent; however, drip is more efficient than micro-sprinkler irrigation, with ~38% water savings.
Characterization and Modeling of Reversible Antibody Self-Association Provide Insights into Behavior, Prediction, and Correction
Authors: Mieczkowski Carl , Cheng Alan , Fischmann Thierry , Hsieh Mark , Baker Jeanne , Uchida Makiko , Raghunathan Gopalan , Strickland Corey , Fayadat-Dilman Laurence
Published: February 2021

Reversible antibody self-association, while having major developability and therapeutic implications, is not fully understood or readily predictable and correctable. For a strongly self-associating humanized mAb variant, resulting in unacceptable viscosity, the monovalent affinity of self-interaction was measured in the low μM range, typical of many specific and biologically relevant protein–protein interactions. A face-to-face interaction model extending across both the heavy-chain (HC) and light-chain (LC) Complementary Determining Regions (CDRs) was apparent from biochemical and mutagenesis approaches as well as computational modeling. Light scattering experiments involving individual mAb, Fc, Fab, and Fab’2 domains revealed that Fabs self-interact to form dimers, while bivalent mAb/Fab’2 forms lead to significant oligomerization. Site-directed mutagenesis of aromatic residues identified by homology model patch analysis and self-docking dramatically affected self-association, demonstrating the utility of these predictive approaches, while revealing a highly specific and tunable nature of self-binding modulated by single point mutations. Mutagenesis at these same key HC/LC CDR positions that affect self-interaction also typically abolished target binding with notable exceptions, clearly demonstrating the difficulties yet possibility of correcting self-association through engineering. Clear correlations were also observed between different methods used to assess self-interaction, such as Dynamic Light Scattering (DLS) and Affinity-Capture Self-Interaction Nanoparticle Spectroscopy (AC-SINS). Our findings advance our understanding of therapeutic protein and antibody self-association and offer insights into its prediction, evaluation and corrective mitigation to aid therapeutic development.
The Human Gut Microbe Bacteroides thetaiotaomicron Suppresses Toxin Release from Clostridium difficile by Inhibiting Autolysis
Authors: Elahi Miad , Nakayama-Imaohji Haruyuki , Hashimoto Masahito , Tada Ayano , Yamasaki Hisashi , Nagao Tamiko , Kuwahara Tomomi
Published: February 2021

Disruption of the human gut microbiota by antibiotics can lead to Clostridium difficile (CD)-associated diarrhea. CD overgrowth and elevated CD toxins result in gut inflammation. Herein, we report that a gut symbiont, Bacteroides thetaiotaomicron (BT), suppressed CD toxin production. The suppressive components are present in BT culture supernatant and are both heat- and proteinase K-resistant. Transposon-based mutagenesis indicated that the polysaccharide metabolism of BT is involved in the inhibitory effect. Among the genes identified, we focus on the methylerythritol 4-phosphate pathway gene gcpE, which supplies the isoprenoid backbone to produce the undecaprenyl phosphate lipid carrier that transports oligosaccharides across the membrane. Polysaccharide fractions prepared from the BT culture suppressed CD toxin production in vitro; the inhibitory effect of polysaccharide fractions was reduced in the gcpE mutant (ΔgcpE). The inhibitory effect of BT-derived polysaccharide fraction was abrogated by lysozyme treatment, indicating that cellwall-associated glycans are attributable to the inhibitory effect. BT-derived polysaccharide fraction did not affect CD toxin gene expression or intracellular toxin levels. An autolysis assay showed that CD cell autolysis was suppressed by BT-derived polysaccharide fraction, but the effect was reduced with that of ΔgcpE. These results indicate that cell wall-associated glycans of BT suppress CD toxin release by inhibiting cell autolysis.
Investigation of the Prevalence of Antibiotic Resistance Genes According to the Wastewater Treatment Scale Using Metagenomic Analysis
Authors: Yoo Keunje , Lee Gihan
Published: February 2021

Although extensive efforts have been made to investigate the dynamics of the occurrence and abundance of antibiotic resistance genes (ARGs) in wastewater treatment plants (WWTPs), understanding the acquisition of antibiotic resistance based on the WWTP scale and the potential effects on WWTPs is of relatively less interest. In this study, metagenomic analysis was carried out to investigate whether the WWTP scale could be affected by the prevalence and persistence of ARGs and mobile genetic elements (MGEs). As a result, 152 ARG subtypes were identified in small-scale WWTP samples, while 234 ARG subtypes were identified in large-scale WWTP samples. Among the detectable ARGs, multidrug, MLS (macrolide–lincosamide–streptogramin), sulfonamide, and tetracycline resistance genes had the highest abundance, and large and small WWTPs had similar composition characteristics of ARGs. In MGE analysis, plasmids and integrons were 1.5–2.0-fold more abundant in large-scale WWTPs than in small-scale WWTPs. The profile of bacteria at the phylum level showed that Proteobacteria and Actinobacteria were the most dominant bacteria, representing approximately 70% across large- and small-scale WWTPs. Overall, the results of this study elucidate the different abundances and dissemination of ARGs between large- and small-scale WWTPs, which facilitates the development of next-generation engineered wastewater treatment systems.
Virulence Determinants and Multidrug Resistance of Escherichia coli Isolated from Migratory Birds
Authors: Islam Md. Saiful , Nayeem Md. Mehedi Hasan , Sobur Md. Abdus , Ievy Samina , Islam Md. Amirul , Rahman Saifur , Kafi Md. Abdul , Ashour Hossam M. , Rahman Md. Tanvir
Published: February 2021

Migratory birds are carriers of multidrug resistant pathogenic Escherichia coli. However, their roles in the dissemination of these resistant pathogens are still being neglected in Bangladesh. The present study was therefore carried out to detect multidrug resistant E. coli. In addition, these isolates were also screened for the presence of avian pathogenic E. coli (APEC)-associated virulence genes. A total of 66 fecal matter samples of migratory birds were screened. E. coli were isolated and identified by culturing and biochemical tests followed by polymerase chain reaction (PCR). APEC-associated virulence genes were detected by PCR. Disk diffusion assays were employed to investigate antibiogram profiles. Bivariate analysis was performed to assess correlations in resistance patterns between antimicrobials and to assess associations between virulence genes of E. coli. Among the 66 samples assessed by PCR, 55 (83.33%) were found positive for E. coli. Of these 55 isolates, the APEC-associated virulence gene fimC was detected in 67.27% of the isolates, which was significantly higher than in the cases of iucD (29.09%) and papC (5.45%) genes. In addition, three isolates were found positive for all three virulence genes, while 23 and 12 isolates were positive for one and two virulence genes respectively. In the bivariate analysis, significant associations were detected between fimC and iucD virulence genes. Using the antibiogram, all E. coli isolates were found to be multidrug resistant (MDR). The isolates exhibited 100% resistance against ampicillin and erythromycin in addition to varying percentages of resistance against streptomycin, tetracycline, ciprofloxacin, and chloramphenicol. Highly positive correlations between tetracycline and ciprofloxacin, chloramphenicol and ciprofloxacin, chloramphenicol and tetracycline were observed by bivariate analysis. To the best of our knowledge, this is the first study that reports APEC-associated virulence genes of MDR E. coli from migratory birds in Bangladesh. Results indicate that migratory birds are reservoirs of MDR E. coli isolates carrying APEC-associated virulence genes, which can seriously contribute to the development of human and animal diseases.
Quantitative and Predictive Modelling of Lipid Oxidation in Mayonnaise
Authors: Merkx Donny W. H. , Swager Andries , van Velzen Ewoud J. J. , van Duynhoven John P. M. , Hennebelle Marie
Published: February 2021

Food emulsions with high amounts of unsaturated fats, such as mayonnaise, are prone to lipid oxidation. In the food industry, typically accelerated shelf life tests are applied to assess the oxidative stability of different formulations. Here, the appearance of aldehydes at the so-called onset time, typically weeks, is considered a measure for oxidative stability of food emulsions, such as mayonnaise. To enable earlier assessment of compromised shelf-life, a predictive model for volatile off-flavor generation is developed. The model is based on the formation kinetics of hydroperoxides, which are early oxidation products and precursors of volatile aldehydes, responsible for off-flavor. Under accelerated shelf-life conditions (50 °C), hydroperoxide (LOOH) concentration over time shows a sigmoidal curvature followed by an acceleration phase that occurs at a LOOH-concentration between 38–50 mmol/kg, here interpreted as a critical LOOH concentration (CCLOOH). We hypothesize that the time at which CCLOOH was reached is related to the onset of aldehyde generation and that the characterization of the LOOH-generation curvature could be based on reaction kinetics in the first days. These hypotheses are tested using semi-empirical models to describe the autocatalytic character of hydroperoxide formation in combination with the CCLOOH. The Foubert function is selected as best describing the LOOH-curvature and is hence used to accurately predict onset of aldehyde generation, in most cases within several days of shelf-life. Furthermore, we find that the defining parameters of this model could be used to recognize antioxidant mechanisms at play.
AFM Study of the Influence of Glycerol Flow on Horseradish Peroxidase near the in/out Linear Sections of a Coil
Authors: Ivanov Yuri D. , Pleshakova Tatyana O. , Shumov Ivan D. , Kozlov Andrey F. , Ivanova Irina A. , Ershova Maria O. , Tatur Vadim Yu. , Ziborov Vadim S.
Published: February 2021

Flow-based coiled systems, through which a heat transfer fluid (such as glycerol) is pumped, are widely used for thermal stabilization of bioreactors and biosensor cuvettes and cells. Previously, using horseradish peroxidase (HRP) as a model protein, we have demonstrated that the incubation of a protein solution in a flow-based system over coiled pipe with flowing glycerol leads to a change in the adsorption properties of the protein macromolecules. Herein, we have studied the effect of the glycerol flow on the properties of HRP, the solution of which was placed differently: i.e., near either the inflow or the outflow linear sections of the pipe, while the coiled section of the pipe was shielded with a grounded metallic cover. Atomic force microscopy (AFM) has been employed in order to visualize the HRP protein macromolecules adsorbed from its solution onto the mica substrate surface. The quantity of adsorbed protein was estimated based on the AFM data. The enzymatic activity of HRP was estimated by spectrophotometry. We demonstrate that a change in the properties of HRP enzyme was observed after the incubation of its solution near the inflow/outflow linear sections of the pipe with flowing glycerol. Namely, after the incubation of HRP solution near the inflow section, a decrease in the protein adsorption onto mica was observed, but its enzymatic activity remained unchanged in comparison to the control sample. In another case, when the HRP solution was incubated near the outflow section, an increased protein adsorption was observed, while the enzyme exhibited considerably lower activity.
Assessment of GPM-Era Satellite Products’ (IMERG and GSMaP) Ability to Detect Precipitation Extremes over Mountainous Country Nepal
Authors: Nepal Bikash , Shrestha Dibas , Sharma Shankar , Shrestha Mandira Singh , Aryal Deepak , Shrestha Nitesh
Published: February 2021

The reliability of satellite precipitation products is important in climatic and hydro-meteorological studies, which is especially true in mountainous regions because of the lack of observations in these areas. Two recent satellite rainfall estimates (SREs) from Global Precipitation Measurement (GPM)-era—Integrated Multi-Satellite Retrievals for Global Precipitation Measurement (IMERG-V06) and gauge calibrated Global Satellite Mapping of Precipitation (GSMaP-V07) are evaluated for their spatiotemporal accuracy and ability to capture extreme precipitation events using 279 gauge stations from southern slope of central Himalaya, Nepal, between 2014 and 2019. The overall result suggests that both SREs can capture the spatiotemporal precipitation variability, although they both underestimated the observed precipitation amount. Between the two, the IMERG product shows a more consistent performance with a higher correlation coefficient (0.52) and smaller bias (−2.49 mm/day) than the GSMaP product. It is worth mentioning that the monthly gauge-calibrated IMERG product yields better detection capability (higher probability of detection (POD) values) of daily precipitation events than the daily gauge calibrated GSMaP product; however, they both show similar performance in terms of false alarm ratio (FAR) and critical success index (CSI). Assessment based on extreme precipitation indices revealed that the IMERG product outperforms GSMaP in capturing daily precipitation extremes (RX1Day and RX5Day). In contrast, the GSMaP product tends to be more consistent in capturing the duration and threshold-based precipitation extremes (consecutive dry days (CDD), consecutive wet days (CWD), number of heavy precipitation days (R10mm), and number of extreme precipitation days (R25mm)). Therefore, it is suggested that the IMERG product can be a good alternative for monitoring daily extremes; meanwhile, GSMaP could be a better option for duration-based extremes in the mountainous region.
Computational Challenges in Tissue Engineering for the Spine
Authors: Castro André P. G.
Published: February 2021

This paper deals with a brief review of the recent developments in computational modelling applied to innovative treatments of spine diseases. Additionally, it provides a perspective on the research directions expected for the forthcoming years. The spine is composed of distinct and complex tissues that require specific modelling approaches. With the advent of additive manufacturing and increasing computational power, patient-specific treatments have moved from being a research trend to a reality in clinical practice, but there are many issues to be addressed before such approaches become universal. Here, it is identified that the major setback resides in validation of these computational techniques prior to approval by regulatory agencies. Nevertheless, there are very promising indicators in terms of optimised scaffold modelling for both disc arthroplasty and vertebroplasty, powered by a decisive contribution from imaging methods.
Irisin and Incretin Hormones: Similarities, Differences, and Implications in Type 2 Diabetes and Obesity
Authors: Marrano Nicola , Biondi Giuseppina , Borrelli Anna , Cignarelli Angelo , Perrini Sebastio , Laviola Luigi , Giorgino Francesco , Natalicchio Annalisa
Published: February 2021

Incretins are gut hormones that potentiate glucose-stimulated insulin secretion (GSIS) after meals. Glucagon-like peptide-1 (GLP-1) is the most investigated incretin hormone, synthesized mainly by L cells in the lower gut tract. GLP-1 promotes β-cell function and survival and exerts beneficial effects in different organs and tissues. Irisin, a myokine released in response to a high-fat diet and exercise, enhances GSIS. Similar to GLP-1, irisin augments insulin biosynthesis and promotes accrual of β-cell functional mass. In addition, irisin and GLP-1 share comparable pleiotropic effects and activate similar intracellular pathways. The insulinotropic and extra-pancreatic effects of GLP-1 are reduced in type 2 diabetes (T2D) patients but preserved at pharmacological doses. GLP-1 receptor agonists (GLP-1RAs) are therefore among the most widely used antidiabetes drugs, also considered for their cardiovascular benefits and ability to promote weight loss. Irisin levels are lower in T2D patients, and in diabetic and/or obese animal models irisin administration improves glycemic control and promotes weight loss. Interestingly, recent evidence suggests that both GLP-1 and irisin are also synthesized within the pancreatic islets, in α- and β-cells, respectively. This review aims to describe the similarities between GLP-1 and irisin and to propose a new potential axis–involving the gut, muscle, and endocrine pancreas that controls energy homeostasis.
A Targeted and Tuneable DNA Damage Tool Using CRISPR/Cas9
Authors: Emmanouilidis Ioannis , Fili Natalia , Cook Alexander W. , Hari-Gupta Yukti , dos Santos Ália , Wang Lin , Martin-Fernandez Marisa L. , Ellis Peter J. I. , Toseland Christopher P.
Published: February 2021

Mammalian cells are constantly subjected to a variety of DNA damaging events that lead to the activation of DNA repair pathways. Understanding the molecular mechanisms of the DNA damage response allows the development of therapeutics which target elements of these pathways. Double-strand breaks (DSB) are particularly deleterious to cell viability and genome stability. Typically, DSB repair is studied using DNA damaging agents such as ionising irradiation or genotoxic drugs. These induce random lesions at non-predictive genome sites, where damage dosage is difficult to control. Such interventions are unsuitable for studying how different DNA damage recognition and repair pathways are invoked at specific DSB sites in relation to the local chromatin state. The RNA-guided Cas9 (CRISPR-associated protein 9) endonuclease enzyme is a powerful tool to mediate targeted genome alterations. Cas9-based genomic intervention is attained through DSB formation in the genomic area of interest. Here, we have harnessed the power to induce DSBs at defined quantities and locations across the human genome, using custom-designed promiscuous guide RNAs, based on in silico predictions. This was achieved using electroporation of recombinant Cas9-guide complex, which provides a generic, low-cost and rapid methodology for inducing controlled DNA damage in cell culture models.
The Impact of Intermittent Fasting on Brain-Derived Neurotrophic Factor, Neurotrophin 3, and Rat Behavior in a Rat Model of Type 2 Diabetes Mellitus
Authors: Elesawy Basem H. , Raafat Bassem M. , Muqbali Aya Al , Abbas Amr M. , Sakr Hussein F.
Published: February 2021

Type 2 diabetes mellitus (T2DM) is known to be associated with an increased risk of dementia, specifically Alzheimer’s disease and vascular dementia. Intermittent fasting (IF) has been proposed to produce neuroprotective effects through the activation of several signaling pathways. In this study, we investigated the effect of IF on rat behavior in type 2 diabetic rats. Forty male Wistar Kyoto rats were divided into four groups (n = 10 for each): the ad libitum (Ad) group, the intermittent fasting group (IF), the streptozotocin-induced diabetic 2 group (T2DM) fed a high-fat diet for 4 weeks followed by a single intraperitoneal (i.p.) injection of streptozotocin (STZ) 25 mg kg−1, and the diabetic group with intermittent fasting (T2DM+IF). We evaluated the impact of 3 months of IF (16 h of food deprivation daily) on the levels of brain-derived neurotrophic factor (BDNF), neurotrophin 3 (NT3), serotonin, dopamine, and glutamate in the hippocampus, and rat behavior was assessed by the forced swim test and elevated plus maze. IF for 12 weeks significantly increased (p < 0.05) the levels of NT3 and BDNF in both control and T2DM rats. Additionally, it increased serotonin, dopamine, and glutamic acid in diabetic rats. Moreover, IF modulated glucose homeostasis parameters, with a significant decrease (p < 0.05) in insulin resistance and downregulation of serum corticosterone level. Interestingly, T2DM rats showed a significant increase in anxiety and depression behaviors, which were ameliorated by IF. These findings suggest that IF could produce a potentially protective effect by increasing the levels of BDNF and NT3 in both control and T2DM rats. IF could be considered as an additional therapy for depression, anxiety, and neurodegenerative diseases.
Preparation and Applications of Fluorinated Graphenes
Authors: Ahmad Yasser , Batisse Nicolas , Chen Xianjue , Dubois Marc
Published: February 2021

The present review focuses on the numerous routes for the preparation of fluorinated graphene (FG) according to the starting materials. Two strategies are considered: (i) addition of fluorine atoms on graphenes of various nature and quality and (ii) exfoliation of graphite fluoride. Chemical bonding in fluorinated graphene, related properties and a selection of applications for lubrication, energy storage, and gas sensing will then be discussed.
Targeted Therapy in Advanced and Metastatic Non-Small Cell Lung Cancer. An Update on Treatment of the Most Important Actionable Oncogenic Driver Alterations
Authors: König David , Savic Prince Spasenija , Rothschild Sacha I.
Published: February 2021

Due to groundbreaking developments and continuous progress, the treatment of advanced and metastatic non-small cell lung cancer (NSCLC) has become an exciting, but increasingly challenging task. This applies, in particular, to the subgroup of NSCLC with oncogenic driver alterations. While the treatment of epidermal growth factor receptor (EGFR)-mutated and anaplastic lymphoma kinase (ALK)-rearranged NSCLC with various tyrosine kinase inhibitors (TKIs) is well-established, new targets have been identified in the last few years and new TKIs introduced in clinical practice. Even for KRAS mutations, considered for a long time as an “un-targetable” alteration, promising new drugs are emerging. The detection and in-depth molecular analysis of resistance mechanisms has further fueled the development of new therapeutic strategies. The objective of this review is to give a comprehensive overview on the current landscape of targetable oncogenic alterations in NSCLC.
Evaluating the Epithelial-Mesenchymal Program in Human Breast Epithelial Cells Cultured in Soft Agar Using a Novel Macromolecule Extraction Protocol
Authors: Lau Hiu Yeung , Tang Jingyi , Casey Patrick J. , Wang Mei
Published: February 2021

The ability to grow in anchorage-independent conditions is an important feature of malignant cells, and it is well-established that cellular phenotypes in adherent cultures can differ widely from phenotypes observed in xenografts and anchorage-independent conditions. The anchorage-independent soft-agar colony formation assay has been widely used as a bridge between adherent cell cultures and animal tumor studies, providing a reliable in vitro tool to predict the tumorigenicity of cancer cells. However, this functional assay is limited in its utility for molecular mechanistic studies, as currently there is no reliable method that allows the extraction of biological macromolecules from cells embedded in soft-agar matrices, especially in experimental conditions where no visible colonies form. We developed a set of new methods that enable the extraction of DNA, RNA and proteins directly from cells embedded in soft agar, allowing for a wide range of molecular signaling analysis. Using the new methods and human mammary epithelial cells (HMECs), we studied the role of epithelial-mesenchymal transition (EMT) in the ability of HMECs to form colonies in soft agar. We found that, when cultured in soft agar instead of in adherent cultures, immortalized non-malignant HME-hTERT cells upregulated the epithelial program, which was noted to be necessary for their survival in this anchorage-independent condition. Overexpression of SV40 small T antigen (ST) or the EMT master-regulator SNAI1 negates this requirement and significantly enhances colony formation in soft agar driven by mutant-RAS. Interestingly, we found that, similar to SNAI1, ST also promotes EMT changes in HMECs, providing further support for EMT as a prerequisite for the efficient anchorage-independent colony formation driven by mutant-RAS in our HMEC model.
Serum CYFRA 21.1 Level Predicts Disease Course in Thyroid Cancer with Distant Metastasis
Authors: Jeong Chaiho , Lee Jeongmin , Yoon Hyukjin , Ha Jeonghoon , Kim Min-Hee , Bae Ja-Seong , Jung Chan-Kwon , Kim Jeong-Soo , Kang Moo-Il , Lim Dong-Jun
Published: February 2021

Background: Serum Cyfra 21.1, the soluble fragment of CK19, has been used as a prognostic tumor marker in various cancers, indicating poor tumor differentiation and increased metastasis. Methods: We analyzed the serum Cyfra 21.1 level in 51 consecutive patients with thyroid cancer manifesting distant metastasis treated with prior total thyroidectomy. Serum Cyfra 21.1 levels of 26 thyroid cancer patients without metastasis and 50 healthy individuals were used for comparison. Results: Higher serum Cyfra 21.1 levels were detected in thyroid cancer patients with distant metastasis compared with healthy subjects and thyroid cancer patients without metastasis (p = 0.012). Serum Cyfra 21.1 levels were significantly increased in patients with positive BRAF V600E mutation (p = 0.019), undergoing Tyrosine Kinase Inhibitor (TKI) therapy (p = 0.008), with radioiodine-refractory status (p = 0.047), and in disease progression compared with those manifesting stable disease (p = 0.007). In progressive disease with undetectable or unmonitored thyroglobulin because of thyroglobulin antibody, serum Cyfra 21.1 was useful as a biomarker for follow-up of disease course. Conclusion: Serum Cyfra 21.1 in thyroid cancer patients might represent an alternative biomarker predicting tumor progression, especially in cases not associated with serum Tg levels.
Prediction of Excess Enthalpy Using Volume-Translated Peng–Robinson Equation of State
Authors: Köhn Christian , Kanzler Ulrike , Reichert Christian , Seyfang Bernhard Christian
Published: February 2021

In this work volume-translated Peng–Robinson group contribution equation of state was used to calculate excess enthalpies. Four model systems were selected with the purpose to compare experimental and predicted enthalpy values at different temperatures. After the calculations were performed in Matlab software, results were verified with free software tool of Dortmunder Datenbank (DDB). In a next step, the mixing process and interaction forces were described on the basis of the sign and course of enthalpy values. The endothermic behavior of three systems could be well predicted, while for the most polar system, predictions were less precise. Furthermore, the discrepancy between experimental data from the literature and predicted values was discussed to evaluate the accuracy of the selected model. Lowest mean deviations (<75 J/mol and <15% at all temperatures) could be stated for alkane/benzene mixtures, while highest deviations could be again observed for the most polar mixture. Although the magnitude of deviations was in agreement with the literature, it could be shown that the selected temperature is of major importance for the quality of predictions. Furthermore, a review of different literature values for the n-hexane/benzene system could reveal that the reliability of experimental data has to be carefully checked.
Hidden Pseudogap and Excitation Spectra in a Strongly Coupled Two-Band Superfluid/Superconductor
Authors: Tajima Hiroyuki , Pieri Pierbiagio , Perali Andrea
Published: February 2021

We investigate single-particle excitation properties in the normal state of a two-band superconductor or superfluid throughout the Bardeen–Cooper–Schrieffer (BCS) to Bose–Einstein-condensation (BEC) crossover, within the many-body T-matrix approximation for multichannel pairing fluctuations. We address the single-particle density of states and the spectral functions consisting of two contributions associated with a weakly interacting deep band and a strongly interacting shallow band, relevant for iron-based multiband superconductors and multicomponent fermionic superfluids. We show how the pseudogap state in the shallow band is hidden by the deep band contribution throughout the two-band BCS-BEC crossover. Our results could explain the missing pseudogap in recent scanning tunneling microscopy experiments in FeSe superconductors.
TRNGs from Pre-Formed ReRAM Arrays
Authors: Cambou Bertrand , Telesca Donald , Assiri Sareh , Garrett Michael , Jain Saloni , Partridge Michael
Published: February 2021

Schemes generating cryptographic keys from arrays of pre-formed Resistive Random Access (ReRAM) cells, called memristors, can also be used for the design of fast true random number generators (TRNG’s) of exceptional quality, while consuming low levels of electric power. Natural randomness is formed in the large stochastic cell-to-cell variations in resistance values at low injected currents in the pre-formed range. The proposed TRNG scheme can be designed with three interconnected blocks: (i) a pseudo-random number generator that acts as an extended output function to generate a stream of addresses pointing randomly at the array of ReRAM cells; (ii) a method to read the resistance values of these cells with a low injected current, and to convert the values into a stream of random bits; and, if needed, (iii) a method to further enhance the randomness of this stream such as mathematical, Boolean, and cryptographic algorithms. The natural stochastic properties of the ReRAM cells in the pre-forming range, at low currents, have been analyzed and demonstrated by measuring a statistically significant number of cells. Various implementations of the TRNGs with ReRAM arrays are presented in this paper.
Sequencing of Organellar Genomes of Nowellia curvifolia (Cephaloziaceae Jungermanniales) Revealed the Smallest Plastome with Complete Gene Set and High Intraspecific Variation Suggesting Cryptic Speciation
Authors: Sawicki Jakub , Krawczyk Katarzyna , Ślipiko Monika , Szczecińska Monika
Published: February 2021

The leafy liverwort Nowellia curvifolia is a widespread Holarctic species belonging to the family Cephaloziaceae. It is made up of a newly sequenced, assembled and annotated organellar genomes of two European specimens, which revealed the structure typical for liverworts, but also provided new insights into its microevolution. The plastome of N. curvifolia is the second smallest among photosynthetic liverworts, with the shortest known inverted repeats. Moreover, it is the smallest liverwort genome with a complete gene set, since two smaller genomes of Aneura mirabilis and Cololejeunea lanciloba are missing six and four protein-coding genes respectively. The reduction of plastome size in leafy liverworts seems to be mainly impacted by deletion within specific region between psbA and psbD genes. The comparative intraspecific analysis revealed single SNPs difference among European individuals and a low number of 35 mutations differentiating European and North American specimens. However, the genetic resources of Asian specimen enabled to identify 1335 SNPs in plastic protein-coding genes suggesting an advanced cryptic speciation within N. curvifolia or the presence of undescribed morphospecies in Asia. Newly sequenced mitogenomes from European specimens revealed identical gene content and structure to previously published and low intercontinental differentiation limited to one substitution and three indels. The RNA-seq based RNA editing analysis revealed 17 and 127 edited sites in plastome and mitogenome respectively including one non-canonical editing event in plastid chiL gene. The U to C editing is common in non-seed plants, but in liverwort plastome is reported for the first time.
Improved Milk Production from Supplementation of Swamp Buffalo with Molasses Nutrient Blocks Containing 10% Urea
Authors: Windsor Peter , Martin Susan , Khounsy Syseng , Young James , Thomson Peter , Bush Russell
Published: February 2021

Milk production from Asiatic swamp buffalo is a new enterprise in Laos. As yields are limited, provision of high-quality cow-calf molasses nutrient blocks containing 10% urea (UMNB10) may improve productivity. A trial in a recently established commercial buffalo dairy examined dietary supplementation of lactating buffalo cows with UMNB10, with three groups of nine cows in mid-lactation randomly selected. Two groups received ad libitum access to UMBs with the remaining group free of block supplements. All animals were daily fed fresh Napier grass (30 kg), corn (750 gm), rice bran (1.45 kg), plus accessed fresh Mulatto grass. Daily milk production (DMP) and body condition score (BCS) were recorded for the 2 months of access to UMB. Average DMP for the two supplemented groups were 1.02 and 0.96 L, compared to 0.78 L for the control group, suggesting improved milk productivity of 31 and 24% from accessing UMB. Partial budget analysis identified a strong incentive for use of the molasses blocks, with a net profit of USD 408 and USD 295 over a 30-day period for the supplemented groups. A multi-intervention livestock development strategy that includes a combination of nutritional and health interventions has been proposed for scale-out to assist smallholder livestock farming efficiency in developing countries. The use of high-quality molasses blocks may be a simple motivator for these communities to increase the efficiency of large ruminant production, improving rural livelihoods, food security, and potentially, reducing greenhouse gas emissions (GHGe) from ruminant-derived foods.
Administrative Costs and Tariff Rates in the Presence of Customs Evasion: Evidence from Ecuador
Authors: González Aguirre Jazmín , Del Villar Alberto
Published: February 2021

This paper seeks to assess the effectiveness of customs policies in increasing the resources devoted to controlling and inspection. Specifically, it seeks to analyze whether an increase in the administrative cost of collecting taxes on foreign trade in Ecuador contributes to reducing customs fraud. To this end, we identify and estimate a transfer function model (ARIMAX), considering information on foreign trade such as official international trade statistics report and tariff rates, as well as the execution of budgetary expenditure and Ecuador’s gross domestic product (GDP). The period under study includes quarterly series from 2006 to 2018. The results obtained by the model indicate that allocating greater material and budgetary resources to combat customs fraud does not always achieve the objective of reducing customs evasion.
Testing the Role of Trade on Carbon Dioxide Emissions in Portugal
Authors: Leitão Nuno Carlos
Published: February 2021

This article considers the relationship between trade intensity, energy consumption, income per capita, and carbon dioxide emissions from 1970–2016 for the Portuguese economy. Considering the arguments of monopolistic competition, the article tests the hypotheses of trade and energy consumption on climate change. We use the autoregressive distributed lag-ARDL model, quantile regression, and cointegration models such as fully modified ordinary least squares (FMOLS), canonical cointegration regression, and dynamic ordinary least squares (DOLS) as an econometric strategy. The econometric results have support with the literature review. The variables used in this research are integrated with the first differences, as indicated by the unit root test. The empirical study proves that trade intensity contributes to environmental improvements. However, energy consumption presents a positive impact on CO2 emissions. The econometric results also demonstrated that a sustainable environmental system exists in the long run.
Bilevel vs. Passive Equalizers for Second Life EV Batteries
Authors: Mubenga Ngalula Sandrine , Salami Boluwatito , Stuart Thomas
Published: February 2021

Once lithium-ion batteries degrade to below about 80% of their original capacity, they are no longer considered satisfactory for electric vehicles (EVs), but they are still adequate for second-life energy storage applications. However, once this level is reached, capacity fade increases at a much faster rate, and the spread between the cell capacities becomes much wider. If the passive equalizer (PEQ) from the EV is still used, battery capacity remains equal to that of the worst cell in the stack, just like it was in the EV. Unfortunately, the worst cell eventually becomes much weaker than the cell average, and the other cells are not fully utilized. If operated while the battery is in use, an active equalizer (AEQ) can increase the battery capacity to a much higher value close to the cell average, but AEQs are much more expensive and are not considered cost effective. However, it can be shown that the bilevel equalizer (BEQ), a PEQ/AEQ hybrid, also can provide a capacity very close to the cell average and at a much lower cost than an AEQ.
Design of Efficient Floating-Point Convolution Module for Embedded System
Authors: Li Jiao , Zhou Xinjing , Wang Binbin , Shen Huaming , Ran Feng
Published: February 2021

The convolutional neural network (CNN) has made great success in many fields, and is gradually being applied in edge-computing systems. Taking the limited budget of the resources in the systems into consideration, the implementation of CNNs on embedded devices is preferred. However, accompanying the increasingly complex CNNs is the huge cost of memory, which constrains its implementation on embedded devices. In this paper, we propose an efficient, pipelined convolution module based on a Brain Floating-Point (BF16) to solve this problem, which is composed of a quantization unit, a serial-to-matrix conversion unit, and a convolution operation unit. The mean error of the convolution module based on BF16 is only 0.1538%, which hardly affects the CNN inference. Additionally, when synthesized at 400 MHz, the area of the BF16 convolution module is 21.23% and 18.54% smaller than that of the INT16 and FP16 convolution modules, respectively. Furthermore, our module using the TSMC 90 nm library can run at 1 GHz by optimizing the critical path. Finally, our module was implemented on the Xilinx PYNQ-Z2 board to evaluate the performance. The experimental results show that at the frequency of 100 MHz, our module is, separately, 783.94 times and 579.35 times faster than the Cortex-M4 with FPU and Hummingbird E203, while maintaining an extremely low error rate.
Virtual State Feedback Reference Tuning and Value Iteration Reinforcement Learning for Unknown Observable Systems Control
Authors: Radac Mircea-Bogdan , Borlea Anamaria-Ioana
Published: February 2021

In this paper, a novel Virtual State-feedback Reference Feedback Tuning (VSFRT) and Approximate Iterative Value Iteration Reinforcement Learning (AI-VIRL) are applied for learning linear reference model output (LRMO) tracking control of observable systems with unknown dynamics. For the observable system, a new state representation in terms of input/output (IO) data is derived. Consequently, the Virtual State Feedback Tuning (VRFT)-based solution is redefined to accommodate virtual state feedback control, leading to an original stability-certified Virtual State-Feedback Reference Tuning (VSFRT) concept. Both VSFRT and AI-VIRL use neural networks controllers. We find that AI-VIRL is significantly more computationally demanding and more sensitive to the exploration settings, while leading to inferior LRMO tracking performance when compared to VSFRT. It is not helped either by transfer learning the VSFRT control as initialization for AI-VIRL. State dimensionality reduction using machine learning techniques such as principal component analysis and autoencoders does not improve on the best learned tracking performance however it trades off the learning complexity. Surprisingly, unlike AI-VIRL, the VSFRT control is one-shot (non-iterative) and learns stabilizing controllers even in poorly, open-loop explored environments, proving to be superior in learning LRMO tracking control. Validation on two nonlinear coupled multivariable complex systems serves as a comprehensive case study.
Optimal Scheduling of Non-Convex Cogeneration Units Using Exponentially Varying Whale Optimization Algorithm
Authors: Jadoun Vinay Kumar , Prashanth G. Rahul , Joshi Siddharth Suhas , Agarwal Anshul , Malik Hasmat , Alotaibi Majed A. , Almutairi Abdulaziz
Published: February 2021

This paper proposes an Exponentially Varying Whale Optimization Algorithm (EVWOA) to solve the single-objective non-convex Cogeneration Units problem. This problem seeks to evaluate the optimal output of the generator unit to minimize a CHP system’s fuel costs. The nonlinear and non-convex characteristics of the objective function demands a powerful optimization technique. The traditional Whale Optimization Algorithm (WOA) is improved by incorporating four different acceleration functions to fine-tune its performance during exploration and exploitation phases. Among the four variants of the proposed WOA, the emphasis is laid on the EVWOA which uses the exponentially varying acceleration function (EVAF). The proposed EVWOA is tested on six different small-scale to large-scale systems. The results obtained for these six test systems, followed by a statistical study highlight the supremacy of EVWOA for finding the best optimal solution and the convergence traits.
Hydrochemical Characteristics of Thermal Water Reservoir in Lądek-Zdrój in Light of Research into the Borehole LZT-1—The Deepest Borehole in the Sudetes (SW Poland)
Authors: Kiełczawa Barbara , Ciężkowski Wojciech , Wąsik Mirosław , Rasała Marek
Published: February 2021

Lądek-Zdrój is situated within the tectonic unit of the Lądek-Śnieżnik metamorphic complex. Thermal water is captured by five springs and borehole L-2. These waters are characterized by TDS content in the range of 160–230 mg/L and predominance of HCO3− (15–100% meq), SO42+ (10–36% meq), and Na+ (57–91% meq) ions. Increased concentrations of radon, hydrogen sulfide, and fluoride ions (7–13 mg/L) determine the medicinal properties of these waters, classified as thermal waters of Na-HCO3-(SO4), F−, H2S, Rn type, with temperatures of 18 to 30 °C and 41 to 45 °C in springs and in the L-2 borehole, respectively. At the turn of 2018 and 2019, a new borehole LZT-1 was drilled in the area of Lądek-Zdrój. It captured thermal waters with a temperature of 37.4 °C at the outflow. The water temperature at the bottom of the heated borehole reached about 59 °C. The lithology of rocks found in the recharged areas implied that the Ca2+ ions present in the studied waters originated from pyroxenes, amphiboles, calcite, calcium plagioclases, and fluorite. As for Na+ and K+ ions, they originate from sodium plagioclases, microcline, and orthoclase. The probable deposit temperature of waters from this borehole was estimated with the use of chemical geothermometers, as ranging from about 87 °C to 97 °C.
Comparative Analysis of SNP Discovery and Genotyping in Fagus sylvatica L. and Quercus robur L. Using RADseq, GBS, and ddRAD Methods
Authors: Ulaszewski Bartosz , Meger Joanna , Burczyk Jaroslaw
Published: February 2021

Next-generation sequencing of reduced representation genomic libraries (RRL) is capable of providing large numbers of genetic markers for population genetic studies at relatively low costs. However, one major concern of these types of markers is the precision of genotyping, which is related to the common problem of missing data, which appears to be particularly important in association and genomic selection studies. We evaluated three RRL approaches (GBS, RADseq, ddRAD) and different SNP identification methods (de novo or based on a reference genome) to find the best solutions for future population genomics studies in two economically and ecologically important broadleaved tree species, namely F. sylvatica and Q. robur. We found that the use of ddRAD method coupled with SNP calling based on reference genomes provided the largest numbers of markers (28 k and 36 k for beech and oak, respectively), given standard filtering criteria. Using technical replicates of samples, we demonstrated that more than 80% of SNP loci should be considered as reliable markers in GBS and ddRAD, but not in RADseq data. According to the reference genomes’ annotations, more than 30% of the identified ddRAD loci appeared to be related to genes. Our findings provide a solid support for using ddRAD-based SNPs for future population genomics studies in beech and oak.