bluuebunny/crossref_metadata_2025_split huggingface dataset:
Clinical comparison of unilateral biportal endoscopic discectomy with percutaneous endoscopic lumbar discectomy for single l4/5‐level lumbar disk herniation
Authors: Hao Jie , Cheng Jiaqi , Xue Huawei , Zhang Feng 
Published: September 2021

AbstractObjectiveThe purpose of this research was to investigate the outcomes between unilateral biportal endoscopic discectomy (UBE) and percutaneous endoscopic lumbar discectomy (PELD) for the single L4/5‐level lumbar disk herniation (sLDH).MethodsFrom January 2018 to January 2021, a total of 40 patients with sLDH were retrospectively analyzed in this study. All the patients had received spinal surgeries in Affiliated Hospital of Nantong University and Affiliated Nantong Hospital 3 of Nantong University. Among them, 20 patients were treated with PELD (PELD group), and 20 patients were treated with UBE discectomy (UBE group). Postoperative length of hospital stay, estimated blood loss, operation time, and clinical complications of the patients were compared between the two groups. The visual analog scale (VAS) and Oswestry Disability Index (ODI) were measured before surgeries and 3 days, 1, and 6 months after surgeries.ResultsCompared with the UBE group, the PELD group had obviously less intraoperative blood loss, shorter operative time, and shorter hospital stay. The differences in the rate of complications were not statistically significant between the two groups. The VAS score and the ODI score of the two groups had a great reduction after operation. In addition, both the groups had satisfactory clinical outcome; the VAS score and ODI of the PELD group decreased more obviously.ConclusionThe UBE for sLDH yielded similar clinical outcomes to PELD as minimally invasive surgeries; however, PELD is superior to UBE in terms of intraoperative blood loss, operative time, postoperative hospitalization, and short‐term postoperative pain relief. The advantages and disadvantages of the two surgeries should be circumspectly balanced when evaluating a patient for a minimally invasive surgery for sLDH, selecting the most appropriate surgical method for patients.
Systemic inequities and depressive symptomology in Hispanic mothers: A path analysis model
Authors: Crawford Allison D. , Cleveland Lisa , McGrath Jacqueline M. , Berndt Andrea 
Published: September 2021

AbstractBackgroundHispanic mothers are one of the largest groups to give birth. They also experience high rates of morbidity and mortality; however, there is limited data related to their health inequities.PurposeThe purpose of this study was to evaluate systemic inequities associated with discrimination using the Reproductive Justice Framework to observe factors that influenced depressive symptomology in Hispanic women.MethodsA path analysis was conducted to evaluate systemic inequities that influenced postpartum depression using the public database, Listening to Mothers III (LMIII). The sub‐sample consisted of n = 406 Hispanic mothers. Data was initially collected between the years 2011 and 2013.ResultsHispanic mothers were more likely to experience occurrences of perceived discrimination while seeking perinatal healthcare. These occurrences of discrimination led to lower trust in their healthcare providers, lower satisfaction with care, more instances of unwanted medical procedures, the need to feel to hold back comments about their health which ultimately resulted in higher rates of self‐reported postpartum depression. The model fit indices supported the model's plausibility (χ2/df ratio = 3.16, Comparative Fit Index = 0.91, Root Mean Square Error of Approximation = 0.06).ConclusionsThis data supported our hypothesis that the pathway of discriminatory barriers Hispanic mothers experience during pregnancy influence postpartum depression.
Expression of astrocyte‐elevated gene‐1 indicates prognostic value of fluoropyrimidine‐based adjuvant chemotherapy in resectable stage III colorectal cancer
Authors: Lin Long‐Wei , Lai Peng‐Sheng , Chen Ying‐Yin , Chen Chung‐Yu 
Published: September 2021

AbstractIt is unclear which prognostic factor such as pathological features and gene mutation are majorly relevant for stage III disease and whether they aid in determining patients who will be benefit from postoperative adjuvant chemotherapy. The expression of astrocyte‐elevated gene‐1 (AEG‐1), thymidylate synthase (TS), excision repair cross‐complementation group 1 (ERCC1), epidermal growth factor receptor (EGFR), and vascular endothelial growth factor (VEGF) was examined to investigate their role in adjuvant chemotherapy for patients with resectable stage III colorectal cancer (CRC). A significant positive correlation was observed between AEG‐1, TS, ERCC1, EGFR, and VEGF gene expression levels in CRC cell lines, and low AEG‐1 and TS expression were highly sensitive to 5‐fluorouracil treatment. Our results showed that AEG‐1 expression was high in T4 and caused CRC recurrence or metastasis. Patients with T4, high AEG‐1, TS and VEGF expression had a significantly short disease‐free survival and overall survival. In multivariate Cox regression analysis, high AEG‐1 expression could be an independent prognostic factor indicating poor survival in patients with resectable stage III CRC treated with adjuvant chemotherapy. In conclusion, AEG‐1 expression and tumor grade are potential prognostic factors for recurrence and survival in patients with stage III CRC receiving adjuvant fluoropyrimidine‐based chemotherapy.
The effect of individual reminiscence therapy on adaptation difficulties of the elderly: a randomized clinical trial
Authors: Kaplan Tuğçe , Keser İlkay 
Published: September 2021

AbstractBackgroundReminiscence therapy is one of various interventions that can be made to protect and improve the mental health of the elderly. The aim of this study was to evaluate the effect of individual reminiscence therapy given during home visits on adaptation difficulties.MethodThis was a randomized controlled, single‐blind study designed with a pretest–post‐test and follow‐up pattern. We divided the participants, 65 elderly people living in Isparta, Turkey, by simple randomization into intervention (31) and control (34) groups. Individual reminiscence therapy was applied to the intervention group participants for eight weeks during house visits once a week. The weekly topics of the reminiscence therapy included childhood, business life, married life, old items, holidays, traditional dishes, and songs and movies, and were all culture‐specific. No intervention was applied to the control group. Study data were collected by using a Sociodemographic Data Form created by the researchers, the Assessment Scale of Adaptation Difficulty for the Elderly (ASADE), and the Nurses' Observation Scale for Geriatric Patients (NOSGER). Pretest, post‐test, and follow‐up data were collected at the individuals' homes in face‐to‐face interviews.ResultsAfter the eight‐week course of reminiscence therapy, there was a significant decrease in the ASADE mean score for the intervention group (P = 0.003) and a significant increase for the control group (P < 0.001). Significant increases were also found in the mean NOSGER scores for the intervention (P = 0.039) and control (P < 0.001) groups; however, the score increase was higher for the control than for the intervention group. Also, there was a significant difference in the ASADE (P < 0,001) and NOSGER (P = 0.01) mean scores of the intervention and control groups.ConclusionThis study found that individual reminiscence therapy decreased adaptation difficulties in the elderly.
Cognition‐Enhanced Machine Learning for Better Predictions with Limited Data
Authors: Sense Florian , Wood Ryan , Collins Michael G. , Fiechter Joshua , Wood Aihua , Krusmark Michael , Jastrzembski Tiffany , Myers Christopher W. 
Published: September 2021

AbstractThe fields of machine learning (ML) and cognitive science have developed complementary approaches to computationally modeling human behavior. ML's primary concern is maximizing prediction accuracy; cognitive science's primary concern is explaining the underlying mechanisms. Cross‐talk between these disciplines is limited, likely because the tasks and goals usually differ. The domain of e‐learning and knowledge acquisition constitutes a fruitful intersection for the two fields’ methodologies to be integrated because accurately tracking learning and forgetting over time and predicting future performance based on learning histories are central to developing effective, personalized learning tools. Here, we show how a state‐of‐the‐art ML model can be enhanced by incorporating insights from a cognitive model of human memory. This was done by exploiting the predictive performance equation's (PPE) narrow but highly specialized domain knowledge with regard to the temporal dynamics of learning and forgetting. Specifically, the PPE was used to engineer timing‐related input features for a gradient‐boosted decision trees (GBDT) model. The resulting PPE‐enhanced GBDT outperformed the default GBDT, especially under conditions in which limited data were available for training. Results suggest that integrating cognitive and ML models could be particularly productive if the available data are too high‐dimensional to be explained by a cognitive model but not sufficiently large to effectively train a modern ML algorithm. Here, the cognitive model's insights pertaining to only one aspect of the data were enough to jump‐start the ML model's ability to make predictions—a finding that holds promise for future explorations.
A basic model for cell cholesterol homeostasis
Authors: Steck Theodore L. , Tabei S. M. Ali , Lange Yvonne 
Published: September 2021

AbstractCells manage their cholesterol by negative feedback using a battery of sterol‐responsive proteins. How these activities are coordinated so as to specify the abundance and distribution of the sterol is unclear. We present a simple mathematical model that addresses this question. It assumes that almost all of the cholesterol is associated with phospholipids in stoichiometric complexes. A small fraction of the sterol is uncomplexed and thermodynamically active. It equilibrates among the organelles, setting their sterol level according to the affinity of their phospholipids. The activity of the homeostatic proteins in the cytoplasmic membranes is then set by their fractional saturation with uncomplexed cholesterol in competition with the phospholipids. The high‐affinity phospholipids in the plasma membrane (PM) are filled to near stoichiometric equivalence, giving it most of the cell sterol. Notably, the affinity of the phospholipids in the endomembranes (EMs) is lower by orders of magnitude than that of the phospholipids in the PM. Thus, the small amount of sterol in the EMs rests far below stoichiometric capacity. Simulations match a variety of experimental data. The model captures the essence of cell cholesterol homeostasis, makes coherent a diverse set of experimental findings, provides a surprising prediction and suggests new experiments.
Radiographic and anatomical morphometric assessments of heart size in presumed healthy pet guinea pigs
Authors: De Silva Margherita , Bo Pierfrancesco , Dora Genocchi Elisabetta , Tagliavia Claudio , Roccaro Mariana , Grandis Annamaria , Baron Toaldo Marco 
Published: September 2021

AbstractCardiac disease in guinea pigs has been reported in the literature; however, reference intervals for normal radiographic heart size obtained using objective measurement methods have not been provided for this species. The aim of this prospective, reference interval study was to describe cardiac dimensions in presumed healthy guinea pigs using the vertebral heart scale (VHS) from thoracic radiographs, as described for dogs and cats. Furthermore, an anatomical study was carried out to compare the radiographic and anatomical findings. Thoracic radiographs were acquired in right lateral recumbency for 30, client‐owned, conscious, presumed healthy guinea pigs and radiographs were acquired in left lateral recumbency for 10 presumed healthy guinea pigs as comparisons. The influence of sex, age, body weight (BW), and recumbency on the VHS and absolute cardiac measurements was investigated. The median (interquartile range; IQR) VHS was 7.4 (7.1‐7.6). No differences emerged between the VHS measured in right versus left lateral recumbency (P = .41) or between sexes (P = .16). The VHS values were not influenced by age (P = .53) or BW (P = .26). The anatomical study was carried out on 10 guinea pig cadavers, and in situ and ex situ cardiac measurements were taken using a caliper. A median (IQR) 7.5 (7.2‐8.0) VHS was assessed by this anatomical study. The reference intervals provided should be useful tools in the future for the radiographic interpretation of cardiac size in guinea pigs in clinical practice.
Coupling Moving Morphable Voids and Components Based Topology Optimization of Hydrogel Structures Involving Large Deformation
Authors: Qiu Yisong , Zhang Shuaiqi , Zhang Weisheng , Ye Hongfei , Zhang Hongwu , Zheng Yonggang 
Published: September 2021

Abstract
A coupling of moving morphable void and component approach for the topology optimization of hydrogel structures involving recoverable large deformation is proposed in this paper. In this approach, the geometric parameters of moving morphable voids and components are set as design variables to respectively describe the outline and material distribution of hydrogel structures for the first time. To facilitate the numerical simulation of large deformation behavior of hydrogel structures during the optimization process, the design variables are mapped to the density field of the design domain and the density field is then used to interpolate the strain energy density function of the element. Furthermore, the adjoint sensitivity of the optimization formulation is derived and combined with the gradient-based algorithm to solve the topology optimization problem effectively. Finally, two representative numerical examples of the optimization of isotropic hydrogel structures are used to prove the effectiveness of the proposed method, and the optimization design of an anisotropic bionic hydrogel structure is presented to illustrate the applicability of the method. Experimental results are also presented to demonstrate that the explicit topologies obtained from the method can be directly used in the manufacture of hydrogel-based soft devices.
Interpolation and Extrapolation of Optimally Fitted Kinematic Error Model for Five-Axis Machine Tools
Authors: Ma Le , Bristow Douglas A. , Landers Robert G. 
Published: September 2021

Abstract
Machine tool geometric errors are frequently corrected by populating compensation tables that contain position-dependent offsets to each commanded axis position. While each offset can be determined by directly measuring the individual geometric error at that location, it is often more efficient to compute the compensation using a volumetric error model derived from measurements across the entire axis space. However, interpolation and extrapolation of measurements, once explicit in direct measurement methods, become implicit and obfuscated in the curve-fitting process of volumetric error methods. The drive to maximize model accuracy while minimizing measurement sets can lead to significant model errors in workspace regions at or beyond the range of the metrology equipment. In this paper, a method of constructing machine tool volumetric error models is presented in which the characteristics of the interpolation and extrapolation errors are constrained. Using a typical five-axis machine tool compensation methodology, a constraint bounding the tool tip modeled error slope is added to the error model identification process. By including this constraint over the entire space, the geometric errors over the interpolation space are still well identified. Also, the model performance over the extrapolation space is consistent with the behavior of the geometric error model over the interpolation space. The methodology is applied to an industrial five-axis machine tool. In the experimental implementation, for measurements outside of the measured region, an unconstrained model increases the mean residual by 40% while the constrained model reduces the mean residual by 40%.
Application of Ultra-Low NOx Combustor to the MHPS Existing Gas Turbine
Authors: Nishiumi Takashi , Ohara Hirofumi , Miyauchi Kotaro , Nakamura Sosuke , Ai Toshishige , Kataoka Masahito 
Published: September 2021

Abstract
In recent years, MHPS achieved a NET M501J gas turbine combined cycle (GTCC) efficiency in excess of 62% operating at 1,600°C, while maintaining NOx under 25ppm. Taking advantage of our gas turbine combustion design, development and operational experience, retrofits of earlier generation gas turbines have been successfully applied and will be described in this paper.
One example of the latest J-Series technologies, a conventional pilot nozzle was changed to a premix type pilot nozzle for low emission. The technology was retrofitted to the existing F-Series gas turbines, which resulted in emission rates of lower than 9ppm NOx(15%O2) while maintaining the same Turbine Inlet Temperature (TIT: Average Gas Temperature at the exit of the transition piece). After performing retrofitting design, high pressure rig tests, the field test prior to commercial operation was conducted on January 2019.
This paper describes the Ultra-Low NOx combustor design features, retrofit design, high pressure rig test and verification test results of the upgraded M501F gas turbine. In addition, it describes another upgrade of turbine to improve efficiency and of combustion control system to achieve low emissions. Furthermore it describes the trouble-free upgrade of seven (7) units, which was completed by utilizing MHPS integration capabilities, including handling all the design, construction and service work of the main equipment, plant and control systems.
Hybrid Electric Drive Systems in the United States Navy
Authors: Buonamici Gianfranco 
Published: September 2021

Abstract
With an increasing instability and cost fluctuation in the world energy markets, it has become more important to increase the US Navy fleet’s overall fuel efficiency. The Navy’s Energy Program for Security and Independence sets forth goals to reduce its overall consumption of energy and decrease its reliance on petroleum. One way that helps accomplish these goals is through the use of hybrid electric drive systems to replace gas turbine engines to accomplish lower ship speeds. Although gas turbines are power dense and fairly efficient at full load, their fuel efficiency decreases drastically at the lower power levels used when slower speeds are required to accomplish the ship’s mission. It is in this lower speed range where operating gas turbine generators closer to their optimum efficiency levels and powering an electric motor saves a significant amount of fuel.
This paper will discuss two in-service systems developed for various US Navy ships: the Hybrid Electric Drive (HED) system for DDG 103 and the Auxiliary Propulsion System (APS) for LHD 8 and LHA 7. It will describe each of the two configurations and their histories, how they are implemented and increase the capability of the ship, and the resulting fuel efficiencies that have been realized with their use.
Study on Conjugate Thermal Performance of a Steam-Cooled Ribbed Channel with Thick Metallic Walls
Authors: Xi Lei , Xu Liang , Gao Jianmin , Zhao Zhen 
Published: September 2021

Abstract
In this work, a conjugate heat transfer model was established to numerically investigate the conjugate thermal performance of a steam-cooled ribbed channel with thick metallic walls. By employing the software of ANSYS CFX, the flow field in the channel and the temperature field in the solid channel were calculated. The flow behavior, heat transfer performance and temperature gradient distributions of ribbed channels with wall thickness (δ) of 1–5 mm, rib height-to-hydraulic diameter (e/D) of 0.047–0.188, rib pitch-to-height ratio (P/e) of 5–15 and rib angle-of-attack (α) of 30°–90° were compared and analyzed. The optimum structure parameters of thick-wall ribbed channel with higher heat transfer performance and lower maximum temperature gradient were obtained. The results show that the SST k-ω turbulence model is more suitable for the conjugate heat transfer problem of steam in the thick-wall ribbed channels. The friction factor reduces gradually with the increase of Re, increases greatly with the increase of e/D and α, and first increases then decreases with the increase of P/e. The average Nusselt number increases up to 8.81 times, while the maximum temperature gradient decreases about 45.35% when Reynolds number varies from 10,000 to 70,000. The rib angle of about 45°–60°, e/D of 0.188, and P/e of 10 are suitable to obtain the optimum thermal performance of steam flow in the ribbed channel. The influence of δ on the flow and heat transfer characteristics is non-significant.
New Modeling Combining Kinematic and Stiffness Nonlinearity in Under Platform Dampers
Authors: Umehara Ryuichi , Takei Sotaro , Akaki Tomohiro , Kitada Hiroki 
Published: September 2021

Abstract
Turbine blades are used under increasingly severe conditions in order to increase the thermal efficiency of the gas turbines in operation. Friction dampers are often used to reduce the vibration of the blade and improve the plant reliability. Under platform dampers designed to generate friction between platforms and dampers have been widely adopted in gas turbines as one of the friction dampers. It is important to predict the vibration characteristics of such damper blades analytically during the design phase, and many analysis methods have been proposed vigorously. However, the phenomenon of the friction damper is not fully understood because of its complicated behavior due to nonlinearity such as contact and sliding. One of them is the variability of frequency generated in the under platform dampers. Recently, it has been reported on the variability of frequency in the mock-up blade test greatly under small excitation force, due to variability of contact surfaces. As different approach, mechanism of the variability of frequency is explained even if each damper pin has the same dimensions and characteristics of stiffness each other under the range of small vibration without slipped phenomena. In this paper, the phenomenon of this frequency variation is shown based on two physical phenomena. First, it shows the geometric nonlinear characteristics in which the normal load changes by the friction coefficient of the pin and the pin angle. Second, it shows the stiffness nonlinear characteristics in which the contact stiffness changes with the normal load of the pin. Based on the new proposed modeling of combining the geometric nonlinear characteristics and nonlinear stiffness characteristics, the phenomenon is shown in which the relative displacement of the pin changes the load and contact stiffness, and the frequency changes. It also shows that the maximum normal load before sliding is different depending on the friction coefficient and the pin angle, and that when the friction coefficient is large and the damper angle is large, the change in contact stiffness due to the normal load is large and the variability of frequency is large.