bluuebunny/crossref_metadata_2025_split huggingface dataset:
Measuring biological materials mechanics with atomic force microscopy ‐ Determination of viscoelastic cell properties from stress relaxation experiments
Authors: Weber Andreas , Benitez Rafael , Toca‐Herrera José L. 
Published: June 2022

AbstractCells are complex, viscoelastic bodies. Their mechanical properties are defined by the arrangement of semiflexible cytoskeletal fibers, their crosslinking, and the active remodeling of the cytoskeletal network. Atomic force microscopy (AFM) is an often‐used technique for the study of cell mechanics, enabling time‐ and frequency‐dependent measurements with nanometer resolution. Cells exhibit time‐dependent deformation when stress is applied. In this work, we have investigated the stress relaxation of HeLa cells when subjected to a constant strain. We have varied the applied force (1, 2, 4, and 8 nN) and pause time (1, 10, and 60 s) to check for common assumptions for the use of models of linear viscoelasticity. Then, we have applied three models (standard linear solid, five element Maxwell, power law rheology) to study their suitability to fit the datasets. We show that the five element Maxwell model captures the stress relaxation response the best while still retaining a low number of free variables. This work serves as an introduction and guide when performing stress relaxation experiments on soft matter using AFM.Research Highlights
Cells exhibit linear viscoelastic properties when subjected to stress relaxation measurements at the studied different forces and times.
The stress relaxation is best described by a five element Maxwell model.
All three used models capture a softening and fluidization of cells when disrupting actin filaments.
The Clean Water Act and biosolids: A 45‐year chronological review of biosolids land application research in Colorado
Authors: Ippolito James A. , Barbarick Ken A. 
Published: June 2022

AbstractThe 1972 U.S. Clean Water Act set forth the generation of biosolids. In Colorado, biosolids land application research began in 1976 and continues today. Pastureland research suggested that sewage effluent could effectively be land applied to benefit aboveground plant growth and to polish water prior to reaching receiving waters. Forest wildfire–affected ecosystems can also benefit from biosolids applications; application rates of up to 80 Mg ha−1 can lead to greater plant establishment, soil microbial activity, and nutrient turnover and reduced nutrient and heavy metal concentrations in runoff below livestock and USEPA drinking water standards. Long‐term (24‐yr) observations in oil shale–mined lands showed that biosolids (up to 224 Mg ha−1) can have a positive effect on microbial‐mediated nutrient cycling and, in turn, on aboveground plant community structure. Biosolids applications of up to 40 Mg ha−1 in high‐elevation shrubland ecosystems, dominated by Mo‐containing shale deposits, can aid in reducing imbalances between Mo and Cu in soils and plants; excessive plant Mo, when consumed by ruminants, can lead to molybdenosis. Biosolids and lime applications (both at 224 Mg ha−1) have been shown to improve long‐term reclamation success on acid‐generating, heavy metal–containing fluvial mine tailings. Thirty years of grazing land research, focused on soil and aboveground plant benefits, illustrate that soil health and plant productivity can be improved to the greatest extent at biosolids application rates close to 10 Mg ha−1. Finally, 40 yr of dryland agroecosystem research (a) have helped identify biosolids N fertilizer equivalency (∼8 kg N Mg−1) and thus dryland winter wheat application rates (e.g., 4.5–6.7 dry Mg ha−1); (b) have identified first‐year mineralization rates of 25–32%; (c) dispute the “time bomb” theory by showing that plant metal uptake follows an exponential rise to a maximum; (d) showcase economic return to producers via increased wheat grain protein content; (e) suggest that biosolids‐borne proteins and their degradation products are labile C and N sources; (f) have led to long‐term tracking of micronutrients and heavy metals in soils and revealed that plants–soil concentrations will not lead to groundwater degradation and that plants are safe for human consumption; and (g) have shown that biosolids provide Zn, helping to overcome soil deficiencies and enhancing Zn biofortification in wheat grain. This latter point is important because ∼2 billion people globally suffer from Zn deficiencies. Forty‐five years of research in Colorado have proven that biosolids can enhance environmental quality, improve soil health, and produce healthy food products.
Between proper and strong edge‐colorings of subcubic graphs
Authors: Hocquard Herve , Lajou Dimitri , Lužar Borut 
Published: June 2022

AbstractIn a proper edge‐coloring the edges of every color form a matching. A matching is induced if the end‐vertices of its edges induce a matching. A strong edge‐coloring is an edge‐coloring in which the edges of every color form an induced matching. We consider intermediate types of edge‐colorings, where edges of some colors are allowed to form matchings, and the remaining form induced matchings. Our research is motivated by the conjecture proposed in a recent paper of Gastineau and Togni on ‐packing edge‐colorings asserting that, for subcubic graphs, by allowing three additional induced matchings, one is able to save one matching color. We prove that every graph with maximum degree 3 can be decomposed into one matching and at most eight induced matchings, and two matchings and at most five induced matchings. We also show that if a graph is in class I, the number of induced matchings can be decreased by one, hence confirming the above‐mentioned conjecture for class I graphs.
Initial experience with robotic liver resection: Audit of 120 consecutive cases at a single center and comparison with open and laparoscopic approaches
Authors: Kato Yutaro , Sugioka Atsushi , Kojima Masayuki , Kiguchi Gozo , Mii Satoshi , Uchida Yuichiro , Takahara Takeshi , Uyama Ichiro 
Published: June 2022

AbstractBackground/PurposeSurgical outcomes and utility of robotic liver resection (RLR) are undefined.MethodsWe retrospectively studied perioperative and long‐term outcomes of the single‐center 120 RLRs including non‐anatomic (NAR, n = 58) and anatomic (AR, n = 62) resections. To evaluate the feasibility and safety of RLR, perioperative outcomes of RLR (n = 103) were compared to those of open (OLR, n = 495) or laparoscopic (LLR, n = 451) resection in liver‐only resections without reconstruction, using 1:1 propensity score matching (PSM). The changing trends from the earlier to the later RLR cases were assessed. Long‐term outcomes were compared between RLR and LLR.ResultsVarious types of RLR with different surgical difficulties were performed, with mostly comparable postoperative morbidity between AR and NAR, or among AR subtypes. In segmentectomy and sectionectomy cases, perioperative outcomes significantly improved in the later period. In comparison between PSM‐selected OLR and RLR cases (87:87), RLR had significantly longer operative time, less blood loss, and shorter hospital stay. PSM‐selected LLR and RLR cases (91:91) showed comparable perioperative outcomes. Overall and recurrence‐free survivals after RLR for newly diagnosed hepatocellular carcinoma and colorectal metastasis were comparable to those after LLR.ConclusionsRLR is applicable to various types of liver resection with acceptable perioperative and long‐term outcomes in select patients.
Cementless femoral stem revision in total hip arthroplasty: The periprosthetic clamshell fracture. A biomechanical investigation
Authors: Kastner Philipp , Zderic Ivan , Gueorguiev Boyko , Richards Geoff , Schauer Bernhard , Hipmair Günter , Gotterbarm Tobias , Schopper Clemens 
Published: June 2022

AbstractTo biomechanically evaluate the stability of a diaphyseal anchored, cementless stem in presence of a proximal periprosthetic femoral medial wall defect compared to the stability of the same stem in an intact femur. Twenty‐two paired human cadaveric femora were pairwise assigned either to a fracture group, featuring a proximal medial wall defect involving 40% of the stems medial anchorage distance, or a control group with native specimens. The specimens were tested under a monotonically increasing cyclic axial loading protocol. Load, cycles, and multiples of the respective body weight at implant loosening was measured. Mean initial stiffness was 2243.9 ± 467.9 N/mm for the intact group and 2190.1 ± 474.8 N/mm for the fracture group. Mean load to loosening in the intact group was 3210.5 ± 1073.2 N and 2543.6 ± 576.4 N in the fracture group, with statistical significance. Mean cycles to loosening in the intact group were 27104.9 ± 10731.7 and 20431.5 ± 5763.7 in the fracture group, with statistical significance. Mean multiples of the resulting body weight at loosening in the intact group was 548.3 ± 158.5% and 441.4 ± 104% in the fracture group, with statistical significance. A medial wall defect involving 40% of the medial anchorage distance significantly decreases the axial stability of a diaphyseal anchored stem. However, mechanical failure occurred beyond physiological stress. At loosening rates of about 4 multiples of the body weight in the fracture group, a “safe zone” remains of a 0.5‐fold body weight for maximum loads and twofold body weights for average loads.
Surgical management of 144 diffuse‐type TGCT patients in a single institution: A 20‐year cohort study
Authors: Spierenburg Geert , van der Heijden Lizz , Mastboom Monique J. L. , van Langevelde Kirsten , van der Wal Robert J. P. , Gelderblom Hans , van de Sande Michiel A. J. 
Published: June 2022

AbstractBackground and ObjectivesSurgery is the mainstay of treatment for tenosynovial giant cell tumors (TGCTs). However, achieving a cure through surgery alone remains challenging, especially for the diffuse‐type (D‐TGCT).MethodsOur goal was to describe the surgical management of patients with D‐TGCT related to large joints, treated between 2000 and 2020. We analyzed the effect of (in)complete resections and the presence of postoperative tumor (POT) on magnetic resonance imaging (MRI) on radiological and clinical outcomes.ResultsA total of 144 patients underwent open surgery for D‐TGCT, of which 58 (40%) had treatment before. The median follow‐up was 65 months. One hundred twenty‐five patients underwent isolated open surgeries, in which 25 (20%) patients' D‐TGCT was intentionally removed incompletely. POT presence on the first postoperative MRI was observed in 64%. Both incomplete resections and POT presence were associated with higher rates of radiological progression (73% vs. 44%; Kaplan–Meier [KM] analysis p = 0.021) and 59% versus 7%; KM analysis p < 0.001), respectively. Furthermore, patients with POT presence clinically worsened more often than patients without having POT (49% vs. 24%; KM analysis p = 0.003).ConclusionsD‐TGCT is often resected incompletely and tumor presence is commonly observed on the first postoperative MRI, resulting in worse radiological and clinical outcomes. Therefore, surgeons should try to remove D‐TGCT in toto and consider other multimodal therapeutic strategies.
Manipulation of ROS‐Responsiveness of Dextran with Thioether Side Chains
Authors: Xia Yu , Chen Runhai , Ke Yue , Xiang Zehong , Ma Zhifang , Shi Qiang , Ataullakhanov Fazly I. , Panteleev Mikhail 
Published: June 2022

AbstractReactive oxygen species (ROS) ‐responsive polymers based on thioether are widely used for drug delivery platforms for inflammation. However, the responsiveness of polymers containing thioether is not tunable toward acute and chronic inflammation, respectively. Here, two kinds of thioether molecules are grafted onto the hydroxyl groups of dextran in a simple and efficient manner. The grafted dextrans possess similar macromolecular structure and molecular weight and easily form nanoparticles. Cytotoxicity experiments confirm the good biocompatibility and antioxidant properties of the nanoparticles. The grafted dextran responds to typical ROS molecules in the order of ClO−, KO2, and H2O2. As for H2O2, the grafted dextran with ester group responds much faster than that of the carbonate group, with the former responding six times faster than the latter, which provides opportunities for the treatment of acute and chronic inflammation, respectively. It is demonstrated that the ester group near the thioether renders the oxidation reaction easier than that of carbonate groups because of its lower energy barrier, which is directly confirmed by an in situ nuclear magnetic resonance (NMR) investigation of the reaction between model molecules and H2O2 and theoretical computational simulations. In conclusion, the ROS responsiveness of grafted dextran can be tunable and the grafted dextran exhibits the potential application in inflammation‐involved disease.
Gene editing provides a tool to investigate genes involved in reproduction of pigs
Authors: Geisert Rodney D. , Johns Destiny N. , Pfeiffer Caroline A. , Sullivan Riley M. , Lucas Caroline G. , Simintiras Constantine A. , Redel Bethany K. , Wells Kevin D. , Spencer Thomas E. , Prather Randall S. 
Published: June 2022

AbstractCRISPR‐Cas9 gene editing technology provides a method to generate loss‐of‐function studies to investigate, in vivo, the specific role of specific genes in regulation of reproduction. With proper design and selection of guide RNAs (gRNA) designed to specifically target genes, CRISPR‐Cas9 gene editing allows investigation of factors proposed to regulate biological pathways involved with establishment and maintenance of pregnancy. The advantages and disadvantages of using the current gene editing technology in a large farm species is discussed. CRISPR‐Cas9 gene editing of porcine conceptuses has generated new perspectives for the regulation of endometrial function during the establishment of pregnancy. The delicate orchestration of conceptus factors facilitates an endometrial proinflammatory response while regulating maternal immune cell migration and expansion at the implantation site is essential for establishment and maintenance of pregnancy. Recent developments and use of endometrial epithelial “organoids” to study endometrial function in vitro provides a future method to screen and target specific endometrial genes as an alternative to generating a gene edited animal model. With continuing improvements in gene editing technology, future researchers will be able to design studies to enhance our knowledge of mechanisms essential for early development and survival of the conceptus.
Nonlinear dynamics investigation of contact force in a cam–follower system using the Lyapunov exponent parameter, power spectrum analysis, and Poincaré maps
Authors: Yousuf Louay S. 
Published: June 2022

AbstractThe aim of this article is to detect the detachment between the cam and the follower using the largest Lyapunov exponent parameter, the power density function of fast Fourier transform, and Poinaré maps due to the nonlinear dynamics phenomenon of the follower. The detachment between the cam and the follower was investigated for different cam speeds and different internal distances of the follower guide from inside. This study focuses on the use of the cam–follower system with a bionic quadruped robot through a linkage mechanism. Multishock absorber (spring–damper–mass) systems at the very end of the follower were used to improve the dynamic performance and to reduce the detachment between the cam and the follower. The SolidWorks program was used in the numerical solution, while a high‐speed camera at the foreground of the OPTOTRAK 30/20 equipment was used to identify the follower position. The friction and impact were considered between the cam and the follower and between the follower and its guide. In general, when the cam and the follower are in permanent contact, there is no loss in potential energy, and no impact or restitution. The detachment between the cam and the follower increases with increasing coefficient of restitution in the presence of the impact.
Correlation of BDNF, VEGF, TNF‐α, and S100B with cognitive impairments in chronic, medicated schizophrenia patients
Authors: Chukaew Phatcharee , Bunmak Nutthaya , Auampradit Natchaphon , Siripaiboonkij Apinya , Saengsawang Witchuda , Ratta‐apha Woraphat 
Published: June 2022

AbstractCognitive impairment is a prominent cause of disability in schizophrenia. Although antipsychotic drugs can rescue the psychotic symptoms, the cognitive impairments persist, with no treatment available. Alterations of BDNF, VEGF, TNF‐α, and S100B have been linked to cognitive impairment in several neurological disorders. However, it remains unclear whether their levels are correlated with the cognitive functions of schizophrenia patients. Forty‐one chronic, medicated schizophrenia patients were included in this study. Enzyme‐linked, immunosorbent assays were used to measure the serum concentrations of BDNF, VEGF, TNF‐α, and S100B. Associations between serum protein levels and various domains of the cognitive functions of the schizophrenia patients were observed. We found significant, positive correlations between serum BDNF and the processing speed and attention levels of the patients. Serum VEGF was also positively correlated with their memory and learning functions. In contrast, serum S100B and TNF‐α were negatively correlated with the processing speed and attention of the schizophrenia patients. The findings warrant further investigation of these molecules as potential prognostic markers or treatment targets for cognitive impairment in schizophrenia patients.
Prevalence of falls in noninstitutionalized people aged 65−80 and associations with sex and functional tests: A multicenter observational study
Authors: Blanco‐Blanco Joan , Albornos‐Muñoz Laura , Costa‐Menen Maria Àngels , García‐Martínez Ester , Rubinat‐Arnaldo Esther , Martínez‐Soldevila Jordi , Moreno‐Casbas María Teresa , Bays‐Moneo Ana Beatriz , Gea‐Sánchez Montserrat ,   Otago Project Working Group
Published: June 2022

AbstractFalls have a considerable impact on the functional prognosis of older adults. The main focus of this multicenter, retrospective, observational study was to examine the prevalence of falls in Spanish people aged 65−80 years still living at home. The secondary aims included examining the overall sociodemographic and clinical variables associated with a history of falls and then stratifying these findings by sex. We also aimed to determine the differences between sexes with regard to the history and consequences of falls and to evaluate associations between fall history and functional performance tests. The 747 older adults had all participated in the otago exercise program, which is a progressive home program of strength, balance, and endurance exercises. They were recruited by nurses in 21 primary care centers in 10 Spanish provinces between September 2017 to December 2018. The participants' mean age was 72.2 (SD: 4.3) years, and 67% were women. We recorded sociodemographic and clinical variables, functional performance test results, and any falls and/or injuries in the last 12 months. We found that 32% had fallen, 36% of those had fallen more than once, and 48% had sustained injuries when they fell. The bivariate analysis showed that women had more than twice the odds of falling than men and that living alone and being obese or overweight increased the odds of a fall, although living alone was not associated with falls in the multivariable analysis. Our results could guide the development of risk‐specific fall prevention programs to prevent disabilities in older people.
Adaptive reaching law‐based discrete‐time sliding mode control for mismatched uncertain systems
Authors: Xia Hongwei , Wang Cong , Wang Yanmin , Ren Shunqing 
Published: June 2022

AbstractIn this article, a novel adaptive reaching law is developed to address discrete‐time sliding mode control systems with mismatched uncertainties. By using the high‐order disturbance compensator, a new reduced‐order sliding surface is constructed to avoid redundancy and decrease superfluous computational expense. Then, an adaptive reaching law with adjustable switching gain is designed to guarantee globally fast convergence of sliding variable. Compared with existing similar works, the proposed reaching law has a main advantage that it can obtain arbitrarily small width of quasi sliding mode domain, leading to suppressed chattering. Based on the analysis of the closed‐loop system, the upper bound of steady states is established. The whole control scheme is able to counteract mismatched uncertainties and achieve high‐precision control at the same time. Finally, a simulated example on bank‐to‐turn missiles is given to verify this research achievement.
Experimental study of the compressive properties of a wood–plastic composite at different temperatures
Authors: Xi Fei , Zhao Longlong 
Published: June 2022

AbstractWood–plastic composites (WPCs) are environmentally friendly materials with good weather resistance and low cost. To investigate the feasibility of their use in different environments, a WPC was designed and subjected to a uniaxial compression test at seven temperatures to obtain the failure mode, uniaxial compressive strength, elastic modulus, proportional limit stress, peak stress, and ultimate strain. The results showed the following. The failure modes of the WPC specimens at various temperatures were mainly shear compression failure, double shear failure, and end compression failure. The uniaxial compressive strength and elastic modulus decreased with increasing temperature. Specifically, at temperatures of −60°C, 20°C (normal temperature), and 60°C, the WPC had an average compressive strength of 73.55, 33.7, and 13.51 MPa, respectively, and an average elastic modulus of 7819.11, 6141.71, and 2650.17 MPa, respectively. In terms of the WPC's stress–strain relationship, at a temperature greater than the normal temperature, the WPC had a small peak stress but good ductility; at the normal temperature and below, the WPC had a large peak stress but poor ductility. Based on these findings, the experimental phenomena and characteristic constants were analyzed to establish models of factors that reduce the uniaxial compressive elastic modulus and compressive strength of WPC at different temperatures, to provide a theoretical basis for the mechanical calculations for the application of WPC in various extreme environments.