bluuebunny/crossref_metadata_2025 huggingface dataset:
The Printing Parameters Effects on the Dimensional Accuracy of the Parts Made of Photosensitive Resin
Authors: Boca Marius‐Andrei , Sover Alexandru , Slătineanu Laurențiu
Published: April 2021

The liquid crystal display is a resin additive manufacturing process applied in the dental, jewellery, engineering industries or hobby, in applications where surface quality, level of details and dimensional accuracy are the main requirements. This paper identifies and explains issues concerning the dimensional accuracy, which are experimentally identified using printed samples made from dedicated photosensitive resin material and Gw basic software to determinate the optimal printing parameters.
Realization of Dental Metallic Works Using a 3D Printer Type MYSINT 100 Through the Selective Laser Melting Process
Authors: Tulică Alexandru Constantin , Drugă Corneliu Nicolae
Published: April 2021

The paper presents a series of aspects regarding the design and realization of metal dental works on a 3D printer type MYSINT 100. This printer is based on the process of selective laser melting of metal powders (selective laser melting) to perform metal dental works (crowns dental, dental bridges, dental implants, etc.). The first part of the paper presents a series of information on how to cast metal alloy for dental bridges. The paper shows main stages of CAD‐CAM design of metal dental works using the ExoCAD program. After obtaining the 3D model (s), they are introduced in the Magics software, to identify errors, collisions on the work platform, determine the volume of work and material consumption (metal powder). Later, they are made using the MYSINT 100 printer.
Study of Antimicrobial Activities of Thyme and Propolis of PLA films
Authors: Ardjoum Nadjet , Chibani Nacera , Boukerrou Amar , Djidjelli Hocine
Published: April 2021

Active films using poly(lactic acid) (PLA) as a polymeric matrix containing propolis and Thymus vulgaris concentrations (3, 6, and 9%) as the active agent are developed using a casting method. The purpose is to determine the effects of the incorporation of active agent on the physical properties of the films and to evaluate the antioxidant and antimicrobial activities.
On the Mechanical Properties of Composites Based on Wheat Husk and Polyvinyl Chloride
Authors: Aouat Hassina , Hammiche Dalila , Boukerrou Amar
Published: April 2021

This work is aimed to valorize the agricultural waste based on the wheat husk (WH) by its incorporation as the reinforcing filler in the polyvinyl chloride (PVC) matrix. To improve interfacial adhesion, the fiber is chemically treated with acetic anhydride (AA). Various composite samples made of PVC and WH fibers at different loading rates, i.e., 10, 20, and 30 wt% are prepared. The transmission Fourier transform infrared spectroscopy IRTF results revealed that the reaction of acetylation has occurred. The results indicate a reduction in the mechanical properties according to the load factor as well as an improvement for the treated composites compared to the untreated composites. There is a reduction in the modulus according to the load factor for PVC/WHAA composites compared to the PVC/WH for both the 20 and 30 wt% formulations.
Experimental Stand Design for an Automatic Wiping Board Concept
Authors: Nută Andrei‐Bogdan , Ulmeanu Mihaela‐Elena , Doicin Cristian‐Vasile , Enache Andrei‐George , Tunsoiu Nicolae
Published: April 2021

The current research aims to develop an experimental stand for functionality testing of an automatic wiping board, to establish its optimal working parameters and select the appropriate materials for functional parts based on Finite Element Analysis (FEA) and experiment results. The conducted research started with the conceptual design of the experimental stand and main component identification. Within this stage, a comprehensive bill of materials is done, ensuring that the specifications of each component are in accordance with its’ function within the main assembly. Next, the load cell is fitted with the Arduino board and with a designated computer. The Arduino board is initiated with a programming sequence recommended by the manufacturer and the data acquisition software is programmed using LabView. An initial test of the load cell is undertaken to determine the reading directions and the final experimental stand is assembled. Four tests, each with two travels, are used to analyze the working hypothesis of the wiping board. Results interpretation led to selecting the optimum working parameters of the proposed wiping board concept. The optimum force is used to conduct fatigue FEA on functional parts manufactured from ABS by additive manufacturing and injection molding technologies. Future research includes the integration of a Wi‐Fi and an infrared sensor, to enable remote operation of the system. Also, the functional parts will be 3D printed, fitted onto the experimental stand of the automatic wiping board and tested for fatigue using the parameters set in the FEA simulation.
An Improved Vantage Point Bees Algorithm to Solve Combinatorial Optimization Problems from TSPLIB
Authors: Zeybek Sultan , Ismail Asrul Harun , Hartono Natalia , Caterino Mario , Jiang Kaiwen
Published: April 2021

This paper presents an improved version of the Vantage Point Bees Algorithm (VPBA‐II), which is implemented to solve the Travelling Salesman Problem. The Vantage Point Tree has been used to produce initial tour solutions and also as a global search operator of the proposed algorithm to find the minimal Hamiltonian tour of the Travelling Salesman Problem. VPBA‐II is tested on 15 different benchmark datasets from TSPLIB, particularly for the high dimensional combinatorial solution spaces, and it outperformed the basic Bees Algorithm. The composition of the local search operators combined with Vantage Point Tours perform better except one dataset and achieved optimum results according to best‐known solutions of Travelling Salesman Problem as a best‐case scenario. The experiments prove that Vantage Point Tour construction could be used as initialization and global search operator to improve the basic Bees Algorithm performance on the combinatorial domains.
Assessment on Energy Absorption of Foam Core Sandwich Panels Under Low Velocity Impact
Authors: Mocian Oana Alexandra , Constantinescu Dan Mihai , Indreş Andrei
Published: April 2021

The impact resistance and energy absorption capability of lightweight sandwich panels mainly depend on the material properties and geometrical features of the core. To study the energy absorption capabilities of foam core sandwich panels, low velocity impact tests on panels with polyurethane or polystyrene foam core and aluminum facesheets are carried out. The results show that the sandwich panels with polystyrene foam core are potentially an appropriate candidate for energy absorption applications due to their high absorption capabilities and minimum response force transferred from the sandwich panel.
Behavior of Different PLA Sandwich Structures Loaded in Three Points Bending
Authors: Jiga Gabriel Gh. , Burtoiu Mircea G. , Pascu Nicoleta E. , Dobrescu Tiberiu G.
Published: April 2021

Sandwich structures can be classed as composite materials in that they consist of two or more individual components of differing properties which when combined result in a high‐performance material. In contrast to monolithic composites—which consist of an intimate mixture of fibers (glass, Kevlar, carbon etc.) supported within a continuous matrix (e.g., thermoplastic or thermoset resin)—sandwich structures show a discrete structure in which a core material is bonded to, and faced with, a skin material. The skin material usually shows a high stiffness, whereas the core typically has high compressive and shear strength. The primary advantage of a sandwich composite is very high stiffness‐to‐weight and high bending strength‐to‐weight ratio. The sandwich enhances the flexural rigidity of the structure without adding substantial weight. First of all, the core should possess low density in order to add as little as possible to the total weight of the sandwich construction. In this paper, three different core configurations are been studied: honeycomb, inversed honeycomb and Kagome bonded to aluminum skins. The cores are made from PLA using the FDM (fusion deposition method) procedure, on a 3D printer.
Effects of the Surface Finish on Thin Specimens Made by Electron Beam Melting Technology
Authors: De Luca Alessandro , Lamanna Giuseppe , Caputo Francesco , Borrelli Rosario , Franchitti Stefania , Pirozzi Carmine , Sepe Raffale
Published: April 2021

Additive layer manufacturing (ALM) is increasingly attracting the research and industry community interest due to the several benefits provided by the layer‐by‐layer production approach. With respect to the surface finish, process parameters influence significantly the surface roughness. According to the State of the Art, it is found out that the roughness level may affect the structural performance of ALM products by both quasi‐static and fatigue points of view. In this paper, an experimental investigation is proposed, showing that the roughness level plays a more influent role for thin components, with respect to the quasi‐static response. The investigated ALM process concerns the electron beam melting technology.
Structural Analyses of Biodegradable Printed Samples
Authors: Mazurchevici Simona‐Nicoleta , Carausu Constantin , Popa Ramona‐Iuliana , Ciofu Ciprian , Paunoiu Viorel , Baroiu Nicusor , Nedelcu Dumitru
Published: April 2021

The aim of the present study is to investigate the chemical and physical structure of two printed lignin/PLA based biodegradable polymers, Fiber Wood® and Arboblend V2 Nature reinforced with Extrudr BDP Pearl. Also, are realized correlations with some previous results published by the research team. The analysis methods used are Fourier‐transform infrared spectroscopy and scanning electron microscope analysis. The revealed information's confirm the biodegradable structure of the printed samples, thus, facilitating the understanding of some mechanical and thermal characteristics, making it much easier to offer some recommendations regarding the substitution of nonbiodegradable synthetic thermoplastics with Fiber Wood® and Arboblend V2 Nature reinforced with Extrudr BDP Pear materials.
Ergonomic Assessment Methods Enhanced by IoT and Simulation Tools
Authors: Caterino Mario , Manco Pasquale , Rinaldi Marta , Macchiaroli Roberto , Lambiase Alfredo
Published: April 2021

The advent of Industry 4.0 (I4.0) principles and technologies has been a great boost for manufacturing companies, constantly focused on the production processes optimization in order to reach the double objective of improving productivity and minimizing related costs. Today, the use of I4.0 technologies seems to be more accessible for a large number of companies, allowing to perform a more detailed analysis on their processes by means of experimental data coming directly from the system. In this context, ergonomics, which has been underestimated until 30 years ago, is assuming more and more importance. This paper aims at proposing a methodology focused on an ergonomic analysis carried out by implementing data collected from the field; in particular, a set of inertial sensors integrated in the worker suit detects the body posture. Then, thanks to the Industrial Internet of Things (IIoT), data are transferred to a simulation software in order to quickly evaluate the current ergonomic effort. In this way, it is possible to perform a real‐time evaluation on the workstation design and consider a possible re‐design with the aim of improving ergonomics.
Human Fatigue Evaluation During Smart Working Sessions
Authors: Rinaldi Marta , Caterino Mario , Manco Pasquale , Fruggiero Fabio , Lambiase Alfredo
Published: April 2021

In the entire world, 2020 will be remembered as a pandemic year, in which COVID‐19 virus has forced to lockdown entire cities and countries. In this context, the concept of work is radically changed, especially for production companies that are forced to temporarily close their production plants. On the other hand, other professional figures, such as engineers, analysts, call center workers, school and university professors, etc., are experimenting a different way of working, the so‐called “smart working”, namely a type of work free of time and place constraints. This paper aims at investigating how the change of working conditions affects the perceived fatigue by workers. In particular, an experimental study is conducted on some smart workers by means of the PERCLOS (PERcentage of eyelid CLOSure) method, that allows to evaluate sleepiness by recording workers faces during the job and analyzing their mouths and eyes.
The Influence of Chitosan Biopolymer on Aluminum Corrosion Resistance in Chloride Ions Environment
Authors: Cojocaru Anca , Maior Ioana , Ciobotaru Ioana Alina , Văireanu Dănuţ‐Ionel
Published: April 2021

The paper presents preliminary studies of the corrosion behavior in NaCl solution of a composite made up of a conversion coating of alumina obtained by sulphuric anodization and chitosan biopolymer. The results obtained from the electrochemical studies (potentiodynamic polarization, electrochemical impedance spectroscopy) indicate a decrease of the corrosion current density for alumina–chitosan composite and a corrosion resistance improvement comparing to untreated aluminum. The presence of the alumina–chitisan composite stabilizes the passivation behavior of the anodized samples due to the sealing of the alumina pores with chitosan biopolymer.
Digital Enterprise and Cyber Security Evolution
Authors: Raicu Alexandra , Raicu Gabriel
Published: April 2021

Industry 4.0 requires increased connectivity and the use of standard communication protocols which nowadays imply an increased need to protect critical industrial systems and manufacturing lines from cyber threats. One cannot talk about the evolution of the digital enterprise without cyber security. There are a lot of cyber security incidents related to Industry 4.0 and Internet of Things developments. PLM, as a whole concept, is prone to cyber threats due to complex interactions between management of design data, quality management, process management, portfolio management, supply chain management, customer relationship management, and management of whole things which are related to the product. The paper addresses the evolutionary cyber threats in last decade using public resources. At present, the large companies that supply industrial equipment have also taken into account the aspects of cyber security. The paper, also presents certain approaches from a scientific point of view in Constanta Maritime University (CMU) research center for the cyber security. To address this complex research field, CMU started several years ago, a complex research and innovative project related to advanced research, training, and development of new technologies in maritime cyber security. Using the CMU complex cyber security simulator, it is able to generate some massive scenarios in technical related fields such as maritime operations, technical design, and technical simulations and detect potential vulnerabilities. One of these kinds of activities is treated as potential long term risks due to the nature of induced vulnerabilities in PLM software.
The Application of Surface Plasmon Resonance with As2S3 Waveguide for Alcohols Identification
Authors: Popescu Aurelian , Miclos Siron , Savastru Dan , Baschir Laurentiu
Published: April 2021

In a composite structure, which contains dielectric‐metal interface, waves of electric charge densities can be initiated. The wave intensity decreases exponentially in adjacent media meaning that the wave closely localized at the interface does exist. Label‐free chemical sensors are realized as the propagation constant of the wave is highly sensitive to the refractive index. Surface plasmons can be excited by incident light flow directed at some specific angle (surface plasmon resonance) with a very sharp shape. In the present paper the possibility of identification of several most common alcohols such as methanol, ethanol, propanol, butanol, or pentanol, which have different refractive indices, has been studied. The structure is composed of a coupling prism made of rutile (TiO2), a thin gold film, and an amorphous arsenic sulfide (As2S3) thin film.
Study raises concerns over NIMH clinical research imbalance
Authors: Canady Valerie A.
Published: April 2021

Observing the need for the National Institute of Mental Health (NIMH) to develop better treatments for current patients as well as future ones, authors of a new study say NIMH researchers are leaning more toward basic science research instead of focusing more evenly on patients with serious mental illness.
Joint MH, COVID‐19 campaign offers critical resources
Authors: Canady Valerie A.
Published: April 2021

As COVID‐19 vaccinations and sign‐ups continue amid this pandemic, a new campaign has launched to emphasize the importance of treating its physical and mental health impacts. The focus is on getting vaccinated, getting resources and getting screened.
Bills addressing LGBTQ community concerning to advocates
Authors: Canady Valerie A.
Published: April 2021

A recent spate of bills addressing LGBTQ youth relating to sports and health care has raised concerns among advocates about discrimination and mental health issues for the population.
The deep inferior epigastric lymphatic cable flap connected to gastroepiploic lymph node flap for treatment of refractory chylous ascites: Report of two cases
Authors: Ciudad Pedro , Chen Hung‐Chi , Bustos Samyd S. , Manrique Oscar J. , Bolletta Alberto , Forte Antonio J. , Huayllani Maria T. , Agko Mouchammed , Urbina J. Antonio , Date Shivprasad , Kaya Burak
Published: April 2021

Chylous ascites is the leakage of lipid‐rich lymph into the peritoneal cavity usually due to disruption of lymphatics or increased peritoneal lymphatic pressure. Various surgical options have been proposed to treat chylous ascites but most have shown suboptimal outcomes. The gastroepiploic vascularized lymph node (GE‐VLN) flap has been described previously for the treatment of lymphedema. In chylous ascites, this flap could provide an alternate drainage pathway for the intraperitoneal chylous fluid. The purpose of this report is to present another option for the microsurgical treatment of refractory chylous ascites. Herein, we report two patients with refractory chylous ascites secondary to cancer who have undergone deep inferior epigastric‐based lymphatic “cable” flap (DIE‐LCF) connected to a pedicle GE‐VLN flap. Patients were followed‐up for a minimum of 2 years. Within the first 3 months following surgery, the patient's nutritional parameters improved along with drastic reduction of ascites. At 2 years follow‐up postoperative abdominal circumference decreased significantly. None required further peritoneal paracentesis and all patients were free of chylous ascites symptoms. In conclusion, the DIE‐LCF connected to a pedicle GE‐VLN flap could be a feasible option for the microsurgical treatment of refractory chylous ascites.
Robust stability analysis of a general class of interval delayed fractional order plants by a general form of fractional order controllers
Authors: Ghorbani Majid , Tavakoli‐Kakhki Mahsan
Published: April 2021

In this paper, the robust stability of interval fractional order plants with one time delay controlled by fractional order controllers is investigated in a general form. For robust stability analysis of the closed loop system by the zero exclusion principle, the distance between the origin and the value set of the characteristic function needs to be checked. It is known that the outer vertices of this value set may change at some switching frequencies and the repetitive calculation of these vertices at switching frequencies leads to additional calculations. In this study initially, new necessary and sufficient conditions are proposed to check the robust stability of a delayed fractional order closed loop system. Then, a novel robust stability testing function is presented based on some vertices, which are fixed for all positive frequencies. Therefore, no additional calculation is needed to obtain the outer vertices of the characteristic function value set for any pair of the switching frequencies. Also, a finite frequency range is presented to reduce the computational cost noticeably. Eventually, three numerical examples are given to verify the efficiency of the results of this paper.
A neutral fractional Halanay inequality and application to a Cohen–Grossberg neural network system
Authors: Kassim Mohammed D. , Tatar Nasser‐eddine
Published: April 2021

We extend the well‐known Halanay inequality to the fractional‐order case in presence of distributed delays and delays of neutral type (in the fractional derivative). Both the discrete and distributed neutral delays are investigated. It is proved that solutions decay toward zero in a Mittag–Leffler manner under some rather general conditions. Some large classes of kernels and examples satisfying our assumptions are provided. We apply our findings to prove Mittag–Leffler stability for solutions of fractional neutral network systems of Cohen–Grossberg type.
Carleman estimate for a 1D linear elastic problem involving interfaces: Application to an inverse problem
Authors: Méjri Bochra
Published: April 2021

The aim of this work is to study the stability of the reconstruction of some mechanical parameters that characterize interfaces within linear elastic bodies. The model considered consists of two bonded elastic solids. The adhesive elastic layer between them is a thin interphase that is approximated, by asymptotic analysis, as an interface. The resulting interface model is in turn characterized by a typical spring‐type linear elastic behavior. In this context and on a 1D configuration, we investigate a Carleman‐type estimate that relates to a unique continuation principle. The proof is based on the construction of suitable weight functions: their gradients are non‐zero, the jumps of the derivatives are positive across the interface, and the averages of the derivatives vanish. The design of such weight functions enables the control of the interface terms in the estimates. With this at hand, we establish a Lipschitz stability estimate for the inverse problem of identifying an interface stiffness parameter from measurements that are available on both sides of the external boundary.
Classifying Individuals Into a Dietary Pattern Based on Metabolomic Data
Authors: Prendiville Orla , Walton Janette , Flynn Albert , Nugent Anne P. , McNulty Breige A. , Brennan Lorraine
Published: April 2021

Scope

The objectives are to develop a metabolomic‐based model capable of classifying individuals into dietary patterns and to investigate the reproducibility of the model.

Methods and Results

K‐means cluster analysis is employed to derive dietary patterns using metabolomic data. Differences across the dietary patterns are examined using nutrient biomarkers. The model is used to assign individuals to a dietary pattern in an independent cohort, A‐DIET Confirm (n= 175) at four time points. The stability of participants to a dietary pattern is assessed. Four dietary patterns are derived: moderately unhealthy, convenience, moderately healthy, and prudent. The moderately unhealthy and convenience patterns has lower adherence to the alternative healthy eating index (AHEI) and the alternative mediterranean diet score (AMDS) compared to the moderately healthy and prudent patterns (AHEI = 24.5 and 22.9 vs 26.7 and 28.4,p< 0.001). The dietary patterns are replicated in A‐DIET Confirm, with good reproducibility across four time points. The stability of participants’ dietary pattern membership ranged from 25.0% to 61.5%.

Conclusion

The multivariate model classifies individuals into dietary patterns based on metabolomic data. In an independent cohort, the model classifies individuals into dietary patterns at multiple time points furthering the potential of such an approach for nutrition research.
Magnetic resonance biomarkers in radiation oncology: The report of AAPM Task Group 294
Authors: McGee Kiaran P. , Hwang Ken‐Pin , Sullivan Daniel C. , Kurhanewicz John , Hu Yanle , Wang Jihong , Li Wen , Debbins Josef , Paulson Eric , Olsen Jeffrey R. , Hua Chia‐ho , Warner Lizette , Ma Daniel , Moros Eduardo , Tyagi Neelam , Chung Caroline
Published: April 2021

Purpose

A magnetic resonance (MR) biologic marker (biomarker) is a measurable quantitative characteristic that is an indicator of normal biological and pathogenetic processes or a response to therapeutic intervention derived from the MR imaging process. There is significant potential for MR biomarkers to facilitate personalized approaches to cancer care through more precise disease targeting by quantifying normal versus pathologic tissue function as well as toxicity to both radiation and chemotherapy. Both of which have the potential to increase the therapeutic ratio and provide earlier, more accurate monitoring of treatment response. The ongoing integration of MR into routine clinical radiation therapy (RT) planning and the development of MR guided radiation therapy systems is providing new opportunities for MR biomarkers to personalize and improve clinical outcomes. Their appropriate use, however, must be based on knowledge of the physical origin of the biomarker signal, the relationship to the underlying biological processes, and their strengths and limitations. The purpose of this report is to provide an educational resource describing MR biomarkers, the techniques used to quantify them, their strengths and weakness within the context of their application to radiation oncology so as to ensure their appropriate use and application within this field.
Novel Protocol for Resole Phenol Formaldehyde Resins Synthesis with Tubular Reactor and Characterization
Authors: Pullichola Abdul Habid , Varghese Lity Alen , Unnikrishnan Gopalakrishna Panicker , Das Kottotil Mohan
Published: April 2021

A novel strategy has been established, in the laboratory scale, for the generation of the popular thermosetting resin phenol formaldehyde (PF; resole), through a continuous process using a tubular reactor, which is usually developed in the commercial scale through a batch process. A refractive index technique is employed to evaluate the optimum residence time within the tubular reactor to obtain a commercial grade equivalent of PF resin. The unreacted free formaldehyde level has been found to be very low in the resole resin prepared by using the new route. The initial characterization of the resin has been done through Fourier transform infrared spectroscopy and gel permeation chromatography. The cure characteristics of the resin have been analyzed through differential scanning calorimetry. The degradation features of the cured resole are investigated using a thermo gravimetric analyzer and the fractured surfaces are analyzed through scanning electron microscopy. It has been confirmed that the adverse effects of a batch reactor process can be significantly reduced by adopting a continuous resin manufacturing process for PF resin which can be successfully extended to commercialization after optimization.
Evaluating Alternative Hierarchical Modeling Approaches for the Estimation of Salmonid Smolt Abundance
Authors: Payton Quinn , Som Nicholas A.
Published: April 2021

Calibrated estimates of fisheries population abundance are vital in the development and appraisal of management actions. Capture–recapture (CR) experiments are invaluable monitoring tools for estimating abundance of biological populations in general. Many researchers, including those studying out-migrating juvenile Chinook Salmon Oncorhynchus tshawytscha in the Klamath Basin of Oregon and California, have attempted to employ Bayesian B-splines to smooth temporal variation in abundance estimates. However, concerns about overfitting and reduced precision are common with this approach. We conducted a simulation study assessing the relative fit of the standard Bayesian B-spline implementation—a B-spline model of abundance with a random effects (RE) binomial model of recapture probabilities—in comparison with that of three alternative model options: a B-spline model of abundance with an autoregressive (AR) model of recapture; an AR model of abundance with an RE model of recapture, and an AR model of abundance with an AR model of recapture. We analyzed 1–3 years of CR data from three rotary screw trap sites and simulated data sets of variable completeness to assess each model’s strengths and weaknesses in estimating the underlying data. Results demonstrated that in general, an AR model of abundance coupled with an RE binomial model of recapture was the least biased model, consistently exhibiting no greater than 5% bias in abundance estimates across data sets. The B-spline abundance models were able to produce narrower 95% credible intervals (CRIs), ranging from 15% to 30% of the parameterized annual abundance value, compared to CRI widths between 23% and 54% from the AR models. However, these narrower CRI widths were commonly errant, with coverage probability rates as low as 50–70% in half of the simulated data set collections compared to over 90% coverage for the AR models. These analyses provide valuable insight and caution for researchers employing modern methods of modeling abundance in natural populations.
Long-Term Trends in Juvenile Atlantic Sturgeon Abundance May Signal Recovery in the Hudson River, New York, USA
Authors: Pendleton Richard M. , Adams Robert D.
Published: April 2021

Overfishing, bycatch, and habitat loss and alteration during the late 19th century to the end of the 20th century caused significant declines in Atlantic Sturgeon Acipenser oxyrinchus stock abundances along the Atlantic coast. To prevent further stock reductions, a coastwide harvest moratorium was implemented in 1998. With fishery-dependent data unavailable to inform stock management, fishery-independent surveys contribute vital information for monitoring population trends by providing data for evaluating the effectiveness of the moratorium and for informing recovery planning. In 2004, a standardized monitoring survey was developed to assess trends in the relative abundance of juvenile Atlantic Sturgeon in the Hudson River, New York. The multimesh anchored gill-net survey randomly sampled locations in soft, deep depositional areas of Haverstraw Bay from late February through early May. Predicted length-at-age relationships were used to infer annual age structure and to examine the relationships between age and annual catch rates. Generalized additive regression modeling was used to describe the relationships between the environmental variables and catch rates and to standardize the abundance index to account for variability in environmental conditions over time. Atlantic Sturgeon catch rates generally increased with increasing water temperature and salinity, and the standardized abundance index (accounting for environmental variability) was highly correlated with the nominal abundance index. In the 16 years of annual monitoring, there has been a significant increase in the relative abundance of juvenile Atlantic Sturgeon. The average catch rate in recent years (2012–2019) is more than twice that observed during the first 8 years (2004–2011) of the survey, as the effects of the moratorium are expected to be delayed due to the long maturation period of Atlantic Sturgeon. These trends suggest that juvenile Atlantic Sturgeon in the Hudson River may be recovering in response to the moratorium and demonstrate the need for long-term fisheries-independent monitoring to document abundance trends in slow-maturing, long-lived species.
Influence of Stocking Practices, Predation, and Reservoir Characteristics on the Growth and Recruitment of Saugeye
Authors: Budnik Richard R. , Kallis Jahn L. , Marschall Elizabeth A.
Published: April 2021

Saugeye (female Walleye Sander vitreus × male Sauger S. canadensis) are stocked annually into Ohio reservoirs to maintain popular recreational fisheries. The growth and recruitment of stocked saugeye are highly variable among years and reservoirs, but the causes of this variability are not well understood. Using a multi-year (2004–2019), multi-reservoir (six reservoirs) data set, we implemented mixed-effects models and an information theoretic approach to identify possible predictors of saugeye poststocking growth and recruitment. Top-performing models (those with a difference in Akaike’s information criterion [ΔAICc] <2) explained 38–40% of the variation in stocked saugeye growth (N = 4 models) and 36–47% of the variation in stocked saugeye recruitment (N = 9 models). Specifically, our growth models identified stocking day of year and mean summer (July–August) water temperature as significant predictors, with saugeye experiencing higher daily growth rates when fish were stocked earlier in the year and when summer water temperatures were warmer. Based on the results from our recruitment models, stocking density was identified as the only significant predictor, with greater stocking densities leading to stronger stocked saugeye recruitment. From these relationships, we predict that saugeye fishery production will be greater when managers stock greater densities of saugeye earlier in the year and when summer reservoir temperatures are higher. Despite identifying significant predictors, our models could not explain much of the variation in stocked saugeye growth and recruitment, revealing the complexity of growth and recruitment processes in Ohio reservoirs.
Relating American Eel Abundance to Environmental DNA Concentration in the Bronx River
Authors: Chin Sam Chew , Waldman John , Bednarski Mike , Camhi Merry , LaBelle Jake , Elizabeth Alter S.
Published: April 2021

The American Eel Anguilla rostrata has experienced a marked population decline due to a multitude of threats, including pollution, overfishing, and damming. Government agencies responsible for American Eel management have identified gaps in survey coverage and understanding of habitat needs as critical obstacles to recovery. However, efforts to expand American Eel monitoring are hindered by this species’ resistance to capture, the wide variety of habitats in which they occur, and their extensive natural range, which would be cost prohibitive to survey using established techniques. Surveys based on analysis of environmental DNA (eDNA) may offer an affordable and efficient means of closing these gaps. While eDNA methods are increasingly used as a rapid, minimally invasive means of detecting species presence, attempts to use them to produce quantitative estimates of abundance have yielded mixed results. In order to evaluate the viability of eDNA as a quantitative American Eel monitoring tool, we compared the concentration of American Eel DNA in water samples to estimates of numerical and biomass density measured by electrofishing in the Bronx River, New York. Our results revealed a strong, positive association between DNA concentration and numerical density but no relationship with biomass density. Mass-specific eDNA production rates were found to decline with mean American Eel weight. While further study will be required to determine whether the observed relationship between DNA concentration and numerical abundance is consistent across sites and whether it can be generalized to other systems, our findings suggest that eDNA will likely be a feasible and cost-effective option for surveying American Eel abundance throughout their range.
Efficacy and Temporal Capture Patterns of Bank Poles in the Kansas River: A Novel Sampling Tool for Catfish
Authors: Dean Quintin J. , Hamel Martin J. , Werner Jake P. , Pegg Mark A.
Published: April 2021

Setlines and trotlines are useful tools for sampling catfish populations. These gears offer an alternative to sampling in habitats or conditions that are unsuitable for traditional sampling gears, and they may be capable of sampling a different subset of the population. However, little is known about their efficacy as catfish sampling gear. We developed a standardized method for deploying setlines in the form of bank poles and assessed the catch rate, species composition, and efficacy of bank poles in the Kansas River, Kansas. We also used Lindgren-Pitman hook timers to investigate temporal patterns of capture, retention rates, and optimal soak duration. Bank poles (n = 897) were equipped with 6/0 circle hooks baited with Silver Carp Hypophthalmichthys molitrix cut bait and were deployed overnight during the summers of 2018 and 2019. Bank poles captured a total of seven fish species, with 97% of the species composition being catfishes (n = 258; mean TL = 688 ± 182.7 mm; range = 392–1,310 mm). Blue Catfish Ictalurus furcatus (45%) was the most commonly captured species, followed by Channel Catfish I. punctatus (37%) and Flathead Catfish Pylodictis olivaris (15%). The success rate for hooking and landing fish with bank poles was 29%. There was no difference between total catch rates from standard bank poles and those from bank poles equipped with hook timers. Higher catch rates were observed early in the set time for Channel and Flathead catfish, whereas a relatively steady catch rate was observed for Blue Catfish. Overall, 46% of catfish were caught within 3 h of gear deployment and 72% were caught within 5 h. We recommend adopting shortened soak durations (about 5 h) to prevent bait loss and to optimize fish retention. Our study provides an alternative sampling approach to increase the catch of large individuals and offers insight into the catch dynamics and interactions of passive angling gears.
Range Expansion and Factors Affecting Abundance of Invasive Flathead Catfish in the Delaware and Susquehanna Rivers, Pennsylvania, USA
Authors: Smith Geoffrey D. , Massie Danielle L. , Perillo Joseph , Wagner Tyler , Pierce Daryl
Published: April 2021

Flathead Catfish Pylodictis olivaris have been either intentionally or accidentally introduced into Atlantic Slope drainages extending from Florida to Pennsylvania and have quickly become established. In Pennsylvania, Flathead Catfish were first detected in the Schuylkill River at the Fairmont Dam in 1999 and in the Susquehanna River at Safe Harbor Dam in 2002. The species has since moved throughout the respective basins, with subsequent detections during 244 riverine surveys in these drainages. Fishway and electrofishing surveys in the tidal Schuylkill River, a Delaware River tributary, have documented an increase in abundances since 2004, when the surveys were first implemented. Hoop-net surveys in nontidal large-river reaches found mean (±SD) catch rates varying from 0.00 to 4.51 ± 4.38 fish/series. A Bayesian hierarchical Poisson regression model indicated that Flathead Catfish abundance decreased as the distance from the initial point of detection increased, demonstrating a general pattern of fish expansion upstream from the point of detection. The distance downstream of the nearest dam, although not significant, had a relatively high posterior probability of being negatively correlated with Flathead Catfish abundance. Ongoing and future targeted surveys should help to better understand changes in the distribution and abundance of Flathead Catfish in these systems.
An extended numerical manifold method for unsaturated soil‐water interaction analysis at micro‐scale
Authors: Sun Hao , Wu Zhijun , Zheng Liange , Yang Yongtao , Huang Da
Published: April 2021

To investigate unsaturated soil‐water interaction at micro‐scale, this study extends the numerical manifold method (NMM) by incorporating a soil‐water coupling model considering specific capillary water distribution and capillary force calculation. The soil skeleton is constructed by a soil skeleton generation algorithm with random polygons. To more realistically capture the interaction between soil grains and capillary water, a capillary mechanics‐based geometric algorithm is proposed to iteratively calculate the capillary water distribution. The capillary forces corresponding to the capillary water distribution are calculated based on the Young‐Laplace equation. The proposed capillary water solving framework is first verified by reproducing the soil‐water characteristic curve and the capillary water distribution of an ideal contact‐disk model against analytical solutions. To further validate the ability of the capillary water solving framework to predict hydraulic behavior of the real soil, a laboratory test on the Toyoura sand is reproduced numerically. Then an ideal direct shear test is performed to further validate the two‐way soil‐water coupling procedure, in which a comparison between the numerical and analytical results regarding the shear strength and matric suction is presented. Finally, microscopic hydraulic and compression tests are conducted on two soil specimens with the same porosity and mean grain diameter but different uniformity coefficients. The results elucidate that the extended method is a potential tool to explore unsaturated soil behaviors at micro‐scale.
Household Food Insecurity, Hair Cortisol, and Adiposity Among Tsimane’ Hunter‐Forager‐Horticulturalists in Bolivia
Authors: Bethancourt Hilary J. , Ulrich Matthew A. , Almeida David M. , Rosinger Asher Y.
Published: April 2021

Objectives

This study examined how household food insecurity (HFI) and chronic stress relate to adiposity among Tsimane’ hunter‐forager‐horticulturalists in remote Bolivia with limited access to energy‐dense processed foods that promote weight gain among industrialized populations.

Methods

Retrospective cross‐sectional data on HFI (via the Household Food Insecurity Access Scale [HFIAS]), hair cortisol concentration (HCC), adiposity (BMI, body fat percentage [%BF]), and sociodemographics were collected from 171 men, 164 women, and 167 children. Linear mixed‐effects models tested linear, quadratic, joint, and interactive relationships between adiposity measures and both the HFIAS score and HCC.

Results

Among children, each 3‐point HFIAS score increase was associated with a 0.44‐point higher %BF (SE = 0.22, P = 0.04). However, each 20% increase in HCC was associated with a −0.29‐point difference in %BF (SE = 0.12, P = 0.01). Among men, a slight curvilinear relationship emerged between HFIAS and BMI. HFIAS and HCC were unrelated to adiposity measures among women. HCC did not modify relationships between HFIAS and adiposity in any subgroup.

Conclusions

These findings from a remote, small‐scale population suggest that positive associations between HFI and adiposity are not isolated to contexts of industrialized food environments and heavy reliance on processed foods. However, these dynamics and the role of stress appear to differ by sex and age group.
A case of MuSK antibody‐positive myasthenia gravis patient mimicking amyotrophic lateral sclerosis with four videofluoroscopic examinations
Authors: Kasahara Takashi , Ikeda Saori , Koyama Yuji , Toyokura Minoru , Masakado Yoshihisa
Published: April 2021

Anti‐muscle‐specific tyrosine kinase (MuSK) antibody‐positive myasthenia gravis (MG) patients sometimes present with bulbar symptoms such as tongue atrophy, nasal voice, dysarthria, or dysphagia and subsequent progressive weight loss. These symptoms may be confused with those of bulbar‐onset amyotrophic lateral sclerosis (ALS). We performed four videofluoroscopic evaluations and investigated the clinical course of a MuSK‐MG patient before and after administration of intensive immunotherapies.
α4β7 Integrin expression and blockade in pediatric and young adult gastrointestinal graft‐versus‐host disease
Authors: Ibrahimova Azada , Davies Stella M. , Lane Adam , Jordan Michael B. , Lake Kelly , Litts Bridget , Chaturvedi Vijaya , Owsley Erika , Myers Kasiani C. , Nelson Adam S. , Mehta Parinda A. , Marsh Rebecca A. , Khandelwal Pooja
Published: April 2021

Background

We hypothesized that α4β7 integrin expression on effector memory T cells (TEMs) would be elevated in pediatric hematopoietic stem cell transplant (HSCT) patients before and at diagnosis of acute gastrointestinal graft‐versus‐host disease (GI GVHD) symptoms compared to patients without GVHD, and that clinical blockade of α4β7 integrin with vedolizumab would be effective in pediatric GI GVHD.

Methods

We analyzed surface expression of α4β7 integrin on T cells from 48 pediatric allogeneic HSCT recipients from our biorepository with known clinical outcomes as follows: acute GI GVHD (n = 22), isolated skin GVHD (n = 12), and no GVHD (n = 14). T‐cell analyses were performed 1 week before and at GVHD diagnosis in patients with GVHD, and day +30 after HSCT in patients without GVHD. We describe clinical outcomes of seven additional patients, different from above‐described 48 patients, who received vedolizumab (anti‐α4β7 integrin antibody) for the treatment of steroid‐refractory acute GI GVHD.

Results

Expression of α4β7 integrin on CD8+ TEMs was upregulated in patients with GI GVHD compared to the no GI GVHD (skin GVHD + no GVHD) group 1 week prior to clinical symptoms (p = .02) and at acute GI GVHD diagnosis (p = .05). Four of seven treated patients with clinical steroid‐refractory acute GI GVHD were evaluable for response to vedolizumab. One patient had a complete response at day +28, while two had a partial response, and one had no response. No adverse effects directly attributable to vedolizumab were observed.

Conclusion

Our data suggest a rationale for the blockade of α4β7 integrin for acute GI GVHD management in children.
Proteome characterisation of extracellular vesicles isolated from heart
Authors: Claridge Bethany , Rai Alin , Fang Haoyun , Matsumoto Aya , Luo Jieting , McMullen Julie R. , Greening David W.
Published: April 2021

Cardiac intercellular communication is critical for heart function and often dysregulated in cardiovascular diseases. While cardiac extracellular vesicles (cEVs) are emerging mediators of signalling, their isolation remains a technical challenge hindering our understanding of cEV protein composition. Here, we utilised Langendorff‐collagenase‐based enzymatic perfusion and differential centrifugation to isolate cEVs from mouse heart (yield 3–6 μg/heart). cEVs are ∼200 nm, express classical EV markers (Cd63/81/9+, Tsg101+, Pdcd6ip/Alix+), and are depleted of blood (Alb/Fga/Hba) and cardiac damage markers (Mb, Tnnt2, Ldhb). Comparison with mechanically‐derived EVs revealed greater detection of EV markers and decreased cardiac damage contaminants. Mass spectrometry‐based proteomic profiling revealed 1721 proteins in cEVs, implicated in proteasomal and autophagic proteostasis, glycolysis, and fatty acid metabolism; essential functions often disrupted in cardiac pathologies. There was striking enrichment of 942 proteins in cEVs compared to mouse heart tissue ‐ implicated in EV biogenesis, antioxidant activity, and lipid transport, suggesting active cargo selection and specialised function. Interestingly, cEVs contain marker proteins for cardiomyocytes, cardiac progenitors, B‐cells, T‐cells, macrophages, smooth muscle cells, endothelial cells, and cardiac fibroblasts, suggesting diverse cellular origin. We present a method of cEV isolation and provide insight into potential functions, enabling future studies into EV roles in cardiac physiology and disease.