bluuebunny/crossref_metadata_2025_split huggingface dataset:
Widespread bacterial utilization of guanidine as nitrogen source
Authors: Sinn Malte , Hauth Franziskus , Lenkeit Felina , Weinberg Zasha , Hartig Jörg S. 
Published: February 2021

AbstractGuanidine is sensed by at least four different classes of riboswitches that are widespread in bacteria. However, only very few insights into physiological roles of guanidine exist. Genes predominantly regulated by guanidine riboswitches are Gdx transporters exporting the compound from the bacterial cell. In addition, urea/guanidine carboxylases and associated hydrolases and ABC transporters are often found combined in guanidine‐inducible operons. We noted that the associated ABC transporters are configured to function as importers, challenging the current view that riboswitches solely control the detoxification of guanidine in bacteria. We demonstrate that the carboxylase pathway enables utilization of guanidine as sole nitrogen source. We isolated three enterobacteria (Raoultella terrigena, Klebsiella michiganensis, and Erwinia rhapontici) that utilize guanidine efficiently as N‐source. Proteome analyses show that the expression of a carboxylase, associated hydrolases and transport genes is strongly induced by guanidine. Finding two urea/guanidine carboxylase enzymes in E. rhapontici, we demonstrate that the riboswitch‐controlled carboxylase displays specificity toward guanidine, whereas the other enzyme prefers urea. We characterize the distribution of riboswitch‐associated carboxylases and Gdx exporters in bacterial habitats by analyzing available metagenome data. The findings represent a paradigm shift from riboswitch‐controlled detoxification of guanidine to the uptake and assimilation of this enigmatic nitrogen‐rich compound.
Several geranylgeranyl diphosphate synthase isoforms supply metabolic substrates for carotenoid biosynthesis in tomato
Authors: Barja M. Victoria , Ezquerro Miguel , Beretta Stefano , Diretto Gianfranco , Florez‐Sarasa Igor , Feixes Elisenda , Fiore Alessia , Karlova Rumyana , Fernie Alisdair R. , Beekwilder Jules , Rodríguez‐Concepción Manuel 
Published: February 2021

Summary

Geranylgeranyl diphosphate (GGPP) produced by GGPP synthase (GGPPS) serves as a precursor for many plastidial isoprenoids, including carotenoids. Phytoene synthase (PSY) converts GGPP into phytoene, the first committed intermediate of the carotenoid pathway.

Here we used biochemical, molecular, and genetic tools to characterise the plastidial members of the GGPPS family in tomato (Solanum lycopersicum) and their interaction with PSY isoforms.

The three tomato GGPPS isoforms found to localise in plastids (SlG1, 2 and 3) exhibit similar kinetic parameters. Gene expression analyses showed a preferential association of individual GGPPS and PSY isoforms when carotenoid biosynthesis was induced during root mycorrhization, seedling de‐etiolation and fruit ripening. SlG2, but not SlG3, physically interacts with PSY proteins. By contrast, CRISPR‐Cas9 mutants defective in SlG3 showed a stronger impact on carotenoid levels and derived metabolic, physiological and developmental phenotypes compared with those impaired in SlG2. Double mutants defective in both genes could not be rescued.

Our work demonstrates that the bulk of GGPP production in tomato chloroplasts and chromoplasts relies on two cooperating GGPPS paralogues, unlike other plant species such as Arabidopsis thaliana, rice or pepper, which produce their essential plastidial isoprenoids using a single GGPPS isoform.
The Effect of Laser Bio‐modulation on Dysplastic Lesions, an Animal Study
Authors: Pourshahidi Sara , Ghasem Zadeh Hoseini Elaheh , Shirazian Shiva , Ebrahimi Hooman , Chiniforush Nasim , Alaeddini Mojgan , Etemad‐Moghadam Shahroo , Amaral Mendes Rui 
Published: February 2021

AbstractPotentially malignant disorders are one of the clinical challenges. Dysplasia in these lesions can be a predictor of more potential for malignant changes. Photo‐bio‐modulation in benign lesions has advantages, but there is doubt on its safety in potentially malignant lesions. This study aims to assess if low‐level laser can promote dysplastic changes while the method can play an important role in management of dysplastic lesions. Dysplasia was induced on anterior wall of the buccal pouch of 80 young Syrian male hamsters. Then, hamsters were divided to four groups to receive 4 and 12 sessions irradiation of 660 and 810 nanometers low‐level lasers. For histopathologic study of the tissue, we used light microscopes. Using SPSS, data were analyzed via Wilcoxon signed rank test and Mann–Whitney U‐test. In all of our four groups, the severity of dysplasia had no statistical difference in study sides comparing with their own controls. Wavelength and numbers of laser irradiation sessions had no statistically meaningful effect on the severity of dysplasia either. Low‐level lasers appear to show no relevant or significant effect over the aggravation of the dysplasia's severity. Neither the wavelength nor the number of sessions appear to have any impact in the results.
Neural markers of procrastination in white matter microstructures and networks
Authors: Chen Zhiyi , Liu Peiwei , Zhang Chenyan , Yu Zeyuan , Feng Tingyong 
Published: February 2021

AbstractMore than 15% of adults suffer from pathological procrastination, which leads to substantial harm to their mental and psychiatric health. Our previous work demonstrated the role of three neuroanatomical networks as neural substrates of procrastination, but their potential interaction remains unknown. Three large‐scale independent samples (total n = 901) were recruited. In sample A, tract‐based spatial statistics (TBSS) and connectome‐based graph‐theoretical analysis was conducted to probe association between topological properties of white matter (WM) network and procrastination. In sample B, the above analysis was reproduced to demonstrate replicability. In sample C, machine learning models were built to predict individual procrastination. TBSS results showed a negative association between procrastination and WM integrity of limbic‐prefrontal connection, and a positive relationship between intra‐connection within the limbic system and procrastination. Also, both the efficiency and integrity of limbic WM network were found to be linked to procrastination. The above findings were all confirmed to replicate in an independent sample; prediction models demonstrated that these WM features can predict procrastination accurately in sample C. In conclusion, this study moves forward our understanding of procrastination by clarifying the role of interplay of self‐control and emotional regulation with it.
D‐index as a marker of bloodstream infections in patients with allogeneic hematopoietic stem cell transplantation
Authors: Vijayvargiya Prakhar , Lara Abad Cybele , Esquer Garrigos Zerelda , O'Horo John C. , Walker Randall C. , Hogan William J. , Tande Aaron J. 
Published: February 2021

AbstractBackgroundNeutropenia is a risk factor for development of infections; however, the direct effect of neutropenia on development of bloodstream infection (BSI) is not known. D‐index, which is area between the neutrophil time curve and a neutrophil count of 0.5 × 109/L, incorporates the combined effect of severity and duration of neutropenia. We aimed to evaluate whether D‐index can be used as a marker for BSI in patients with allogeneic stem cell transplantation.MethodWe conducted a retrospective cohort study of patients undergoing allogeneic stem cell transplantation between January 1, 2005, and September 30, 2015. The primary outcome measure was the development of BSI within 30 days of transplantation.ResultsA total of 714 patients were included in the study of whom 101 developed BSI. Patients with BSI had a significantly higher median D‐index value compared with patients who did not have BSI (4990 vs. 3570, P < .001). As a marker, the performance of the D‐index was similar to that of the duration of profound neutropenia (P = .18) and significantly better than the total duration of neutropenia (P = .001).ConclusionThe D‐index performed better than the total duration of neutropenia as a marker for BSI in patients with allogeneic stem cell transplantation. There was no difference between D‐index and, a more easily calculable indicator, duration of profound neutropenia.
An Efficient Assisted Bidirectional Glenn Design With Lowered Superior Vena Cava Pressure for Stage-One Single Ventricle Patients
Authors: Jia Dongjie , Peroni Matthew , Khalapyan Tigran , Esmaily Mahdi 
Published: February 2021

Abstract
Recently, the assisted bidirectional Glenn (ABG) procedure has been proposed as an alternative to the modified Blalock–Taussig shunt (mBTS) operation for neonates with single-ventricle physiology. Despite success in reducing heart workload and maintaining sufficient pulmonary flow, the ABG also raised the superior vena cava (SVC) pressure to a level that may not be tolerated by infants. To lower the SVC pressure, we propose a modified version of the ABG (mABG), in which a shunt with a slit-shaped nozzle exit is inserted at the junction of the right and left brachiocephalic veins. The proposed operation is compared against the ABG, the mBTS, and the bidirectional Glenn (BDG) operations using closed-loop multiscale simulations. Both normal (2.3 Wood units-m2) and high (7 Wood units-m2) pulmonary vascular resistance (PVR) values are simulated. The mABG provides the highest oxygen saturation, oxygen delivery, and pulmonary flow rate in comparison to the BDG and the ABG. At normal PVR, the SVC pressure is significantly reduced below that of the ABG and the BDG (mABG: 4; ABG: 8; BDG: 6; mBTS: 3 mmHg). However, the SVC pressure remains high at high PVR (mABG: 15; ABG: 16; BDG: 12; mBTS: 3 mmHg), motivating an optimization study to improve the ABG hemodynamics efficiency for a broader range of conditions in the future. Overall, the mABG preserves all advantages of the original ABG procedure while reducing the SVC pressure at normal PVR.
An Inconspicuous, Integrated Electronic Travel Aid for Visual Impairment
Authors: Boldini Alain , Garcia Andy Louis , Sorrentino Marc , Beheshti Mahya , Ogedegbe Okpe , Fang Yi , Porfiri Maurizio , Rizzo John-Ross 
Published: February 2021

Abstract
With a globally aging population, visual impairment is an increasingly pressing problem for our society. Visual disability drastically reduces quality of life and constitutes a large cost to the health care system. Mobility of the visually impaired is one of the most critical aspects affected by this disability, and yet, it relies on low-tech solutions, such as the white cane. Many avoid solutions entirely. In part, reluctance to use these solutions may be explained by their obtrusiveness, a strong deterrent for the adoption of many new devices. Here, we leverage new advancements in artificial intelligence, sensor systems, and soft electroactive materials toward an electronic travel aid with an obstacle detection and avoidance system for the visually impaired. The travel aid incorporates a stereoscopic camera platform, enabling computer vision, and a wearable haptic device that can stimulate discrete locations on the user’s abdomen to signal the presence of surrounding obstacles. The proposed technology could be integrated into commercial backpacks and support belts, thereby guaranteeing a discreet and unobtrusive solution.
A Simplified Algorithm for Count Rate Processing in Radiation Monitors That Address Statistical Fluctuations and Spurious Counts
Authors: Nanda Biswamohan , Madhavi Voleti , Suguna Devi S. V. , Balachandran R. 
Published: February 2021

Abstract
While processing the signals from radiation detectors, for finding the true mean-count-rate, algorithms with hybrid pulse collection methodology have been proposed and used over the years. An algorithm based on this technique with a new methodology of adoption and implementation including spurious rejection is proposed here. It enables a specified and controllable error when the mean-count-rate remains within certain predefined limits from its true value. Effort is made to optimize the response time of prediction at low count rates preserving the optimum possible relative-standard-deviation (RSD). Chi-squared test is utilized for verifying the counting system to check if the observed fluctuations are consistent with the expected statistical fluctuations. A C-program code has been developed to test the algorithm. An observed set of detector outputs are given as input to the program and the corresponding Output is analyzed. A comparative study between the proposed method and floating-mean method is presented for the same set of observations. A typical short-lived high voltage (HV) induced spurious noise pattern is fed as input to the program verifying limited-spurious rejection capability of the algorithm. An embedded C program was written for microcontroller implementation of the algorithm. Case-study of a neutron roentgen equivalent man (REM) counter is presented for evaluating response time for various ranges of operation with calculation of RSD at these ranges. This general-purpose algorithm can enhance the read-out accuracy of radiation monitors used for radiation safety applications.
Numerical and Experimental Modeling of the Thermal Flow in a Modern Rotary Transfer Machine
Authors: Robusto Francesco , Croccolo Dario , De Agostinis Massimiliano , Fini Stefano , Olmi Giorgio , Rizzitelli Marco , Vincenzi Nicolò 
Published: February 2021

Abstract
The aim of this study is to estimate the relative displacement between the spindle nose and the clamping vice in a rotary transfer machine due to temperature variations. The study was focused on the relative displacements caused by temperature variations produced by two heat sources: the environment around the machine and the three-axis computer numerical control station during the duty cycle. Regarding the last point, an analytical model was developed, in order to account for different thermal sources inside the three-axis module (e.g., ball-screws, rolling bearings, and guideways friction heat, as well as heat generation in the motor). The complete numerical model was calibrated and successfully validated. A comparison was run between numerical results and experimental data in the framework of trials involving a newly developed transfer machine. Finally, the complete model, considering the combination of both the heat sources, has made it possible to estimate spindle nose-clamp relative displacement during a typical working day, highlighting that the radial displacement risks affecting seriously the accuracy of a workpiece.
Analysis of the Positioning Process of Objects by the System of Oblique Friction Force Fields on the Example of the MSC Adams Model
Authors: Piatkowski Tomasz , Wolski Miroslaw 
Published: February 2021

Abstract
The paper concerns modelling of the rotational positioning process of cuboid objects with the system of oblique friction force fields produced by two conveyors. These conveyors are used when introducing streams of objects onto trays of the cross-belt sorting system. The purpose of positioning is to place the objects parallel to the edges of the trays with the greatest possible precision. The positioning precision depends on the choice of the conveyors’ motion velocities and conveyors’ position to each other, which can be determined on the basis of numerical simulations. During theoretical analyses, contact and friction models available in the MSC Adams environment were taken into account.
Experiment Study for Evaluation of Phase Change Material Cooling Vest’s Effectiveness at Two Melting Points Used by People With Paraplegia During Exercise
Authors: Mneimneh Farah , Ghaddar Nesreen , Ghali Kamel , Moussalem Charbel , Omeis Ibrahim 
Published: February 2021

Abstract
Phase change material (PCM) cooling vests were tested on people with thoracic (T1-T12) spinal cord injury (SCI), also called people with paraplegia (PA), during exercise in heat. The purpose was to reduce heat stress, limit the increase in core temperature, and improve thermal comfort for PA under high metabolic rates and hot ambient conditions. This health risk was a result of thoracic SCI and disruption of thermoregulatory responses in PA. The current study aims to evaluate the efficacy of cooling vest on PA during arm-crank exercise at two melting points, 20°C (V20) and 14°C (V14) compared to no vest test (NV).
Eleven participants with high- (T1-T3) and mid-thoracic SCI (T4-T8) were selected to participate in three tests. Core and skin temperatures and heart rate values were measured during 15-min precondition, 30-min exercise and 15-min recovery. Subjective voting of thermal comfort, sensation, skin wettedness and perceived exertion were recorded during exercise only. The main findings revealed significant reduction in change in core temperature (0.42±0.3°C;0.38±0.2°C) in V20 and V14 compared to NV tests for mid-thoracic group. For high-thoracic group, V20 and V14 were least effective in reducing core temperature (p &gt; 0.05). Improvements in thermal comfort was established when using V14 and V20 compared to NV by 85% and 30% for high-thoracic group and by 72% and 53% for mid-thoracic group.
Fluid Structure Interaction Simulation of a Benchmark Configuration With a Stress Blended-Eddy Simulation Model
Authors: Pratomo Hariyo P. S. 
Published: February 2021

Abstract
In this work, the application of a shear stress transport based-RANS/LES turbulence modelling approach on a fluid-structure interaction (FSI) benchmark is considered after a transient computation of turbulent flow over the configuration on an LES quality mesh is to be performed. Within the unsteady decoupled simulation the scale resolving method successfully produces complex unsteady eddy sizes behind the reference test case. At a subcritical Reynolds number, a numerical Strouhal number of 0.184 which is close to a reference value of 0.18 is demonstrated by the RANS/LES turbulence model. In this scenario, a rubber added on the back part of a fixed circular cylinder is treated as a rigid thin plate during the pure flow simulation. On the LES grid resolution, the shielding function resided in the hybrid limiter of the scale resolving formulation is found to be strong to safeguard the activation of the RANS mode in the near wall region where the demarcation line between the RANS and LES modes uniquely resembles the geometry. Moreover, in the FSI simulation resolved turbulence scales interacting with moving and deforming rubber immersed in the subcritical Reynolds number-turbulent flow are successfully captured by the hybrid modelling technique coupled with a structural solver under the coupling procedure of an implicit partitioned approach. Similar with earlier studies with different scale-resolving proposals on the same FSI case, a periodic oscillating motion of the rubber that is produced from a phase-averaging method is also demonstrated in this present investigation. Nevertheless, a non-physical deformation of the rubber in the spanwise direction occurs. The new FSI result is evaluated with existing results from earlier works as a pivotal basis for further researches, such as implementations of new mesh stiffness model and filter width.
Re-Sizable Quadrupedal Robot Platform: HARQ
Authors: Sohn Kiwon , Hussain Salman , Bradnan Matthew , May Owen 
Published: February 2021

Abstract
This paper presents the development of kinematically adjustable quadrupedal robot platform, HARQ (Human Assistive and Robust Quadruped) which has been designed and built by ART (Assistive Robot Team) in University of Hartford since 2019. The main objective of HARQ is to assist various tasks of human workers in dangerous work environments such as disasters. In this paper, the mechanical design and building processes of HARQ which focused on kinematic adaptivity and low-cost manufacturing as its main technical design requirements are described first. Then, the kinematic analysis and its implementation in the low-level body controller of the quadrupedal robot are described. Lastly, HARQ is tested and evaluated both in a simulated environment using its virtual model and in an outdoor environment using the physically built platform with various whole body motions which are designed for the robot’s navigation.
Energetic and Economic Potential for Load Control for Residential Customers in Austin, TX
Authors: Bandyopadhyay Arkasama , Conger Julia P. , Beagle Emily A. , Webber Michael E. , Leibowicz Benjamin D. 
Published: February 2021

Abstract
This study uses a linear optimization framework to evaluate the effect of different demand response (DR)/load control mechanisms on reduction in peak load and energy consumption from the electricity grid in a home with four major controllable appliances — HVAC (heating, ventilation, and air-conditioning) systems, electric water heaters (EWHs), electric vehicles (EVs), and pool pumps (PPs). Two incentive-based DR methods and four price-based DR schemes — real time pricing (RTP), time-of-use (TOU) rates, critical peak prices (CPP), and variable peak prices (VPP) — are analyzed. Load reduction potential is evaluated for scenarios where the home has both onsite solar and storage, only solar, and no solar or storage. Results show that, from the utility’s perspective, the optimal load control schemes, which result in greatest reduction in peak load and energy consumption from the grid during peak hours, are CPP and VPP (critical price option). By considering the combined effect of demand response, solar generation, and energy storage systems, this study aims to equip electric utilities with the ability to make decisions about dynamic rate design and direct load control to curtail peak demand and shift energy usage.
Manufacturing Capability Index of 3D Printing Parts for Impact Applications
Authors: Schmitz Anne 
Published: February 2021

Abstract
Three-dimensional (3D) printing with high-resolution stereolithography (SLA) has grown in popularity for creating personalized medical devices. 3D printing is now starting to expand to weight-bearing components, e.g. prosthetic feet, as data on the dynamic properties impact and fatigue is published in the literature. The next step towards using 3D printing in impact applications is to assess the capability of the high-resolution SLA process to manufacture components of uniform impact resistance. Because impact testing is destructive, a surrogate measure to check a part’s viability for resisting an impact load also needs to be established. Thirteen notched Izod specimens were printed on a Form2 SLA printer using the manufacturer’s clear V4, photocurable resin. Once all the specimens were printed, washed in isopropyl alcohol, and cured with ultraviolet light, the impact resistance was quantified using a pendulum impact tester in a notched Izod configuration. Then, the hardness of the specimens was quantified using a HBW 10/250 scale. The impact resistance of the clear, SLA polymer was 0.59 ± 0.14 ft-lb/in. With an upper standard limit of 0.53 ft-lb/in, the process capability index was 0.133. Impact resistance and Brinell hardness were not correlated with a Spearman coefficient of r = −0.108, p = 0.73. Since the process capability index was less than one, 3D printing with SLA polymers is not a viable manufacturing process for creating parts of consistent impact resistance. The current technology would lead to too many rejected parts. Also, Brinell hardness and impact strength were not related. Therefore, there is no non-destructive method to spot-check these components before use.