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In the past decade, a lot of work has been reported on the use of polyvinylidene fluoride (PVDF) based thermoplastic composites as energy storage devices, and implant materials. But hitherto little has been reported on the dimensional stability and surface characteristics of 3D-printed PVDF composites after autoclaving for implant applications. In this study, the effect of autoclaving on surface characteristics (Shore-D hardness, surface roughness (Ra), morphological characteristics), and dimensional stability of 3D printed PVDF-hydroxyapatite (HAp)- chitosan (CS) composite has been reported for implant applications. The signal-to-noise (S/N) ratio approach was used to ascertain the best setting of process parameters for 3D printing by fused filament fabrication (FFF) process. This study suggests that the best setting for the FFF process, for the 3D printing of PVDF composite (90%PVDF-8%HAp-2%CS) are the nozzle temperature (NT) of 225°C, raster angle (RA) 0°, and printing speed (PS) 40 mm/s, resulting in Shore-D hardness 48.5 HD (before autoclaving) and 55.0 HD (after autoclaving), dimensional deviation 0.01 mm (after autoclaving). The results are supported by scanning electron microscopy (SEM) and Fourier transmission infrared (FTIR) spectroscopy analysis. [ABSTRACT FROM AUTHOR]

In the recent past some studies have been reported on the compressive, tensile, and flexural properties of 3D-printed polyvinylidene fluoride (PVDF) composite-based intramedullary (IM) pins for canines. However, in actual working conditions (due to trauma or accident), the IM pin may also be under torsional loading conditions. But hitherto little has been testified on the torsional behavior of PVDF composite-based IM pins. This study highlights the torsional behavior at 1 rpm (from 0 to 800° of the angle of twist/rotation) of PVDF composite (PVDF-90%; hydroxyapatite (HAp8%); chitosan (CS2%)) based IM pin fabricated by fused filament fabrication (FFF) process. The study suggests that better torsional properties were obtained for 3D printed samples prepared at nozzle temperature (NT) of 235°C, raster angle (RA) of 45°, and printing speed (PS) of 60 mm/s respectively resulting in a maximum torque of 3.44 Nm at the angle of twist of 800° (as per ASTM A938). The morphological analysis based on scanning electron microscopy (SEM) supports the results of the fractured surface (at cross section) and along the lateral axis. [ABSTRACT FROM AUTHOR]

In the last two decades, several studies have been conducted for the process parametric optimization of fused filament fabrication (FFF) with a variety of thermoplastic composites, especially for mechanical properties. But hitherto less has been conveyed, on the development of dynamic reduced order models (ROMs) for digital twining (DT) of tensile properties (of 3D printed implants/scaffolds) with novel thermoplastic-based composites. In this study, for the generation of dynamic ROM (for hybrid analytics), the signal-to-noise (S/N) ratio was used to ascertain the best settings of parameters for tensile properties of polyvinylidene fluoride (PVDF) composite. The study suggests that the best setting of the FFF process, for the 3D printing of PVDF composite (90% PVDF, 8% hydroxyapatite (HAp), and 2% Chitosan (CS) (for maximizing the tensile properties as per ASTM-D638-Type-V) are nozzle temperature (NT) of 235°C, raster angle (RA) 45°, printing speed (PS) of 60 mm/s respectively resulting in peak load (PL) 394.87 N, peak stress (PSt) 33.92 MPa, Young's modulus (E) 2.606 MPa. For a modulus of toughness (MOT) of 0.484 MPa, the best settings are NT 230°C, RA 90°, and PS 50 mm/s. The results are supported by the morphological analysis. [ABSTRACT FROM AUTHOR]

Polyvinylidene fluoride (PVDF) is one of the established thermoplastics with inherent piezoelectric characteristics. In the past two decades, a lot of work has been reported on the use of virgin Polyvinylidene fluoride thermoplastics for sensing applications. But hitherto little has been reported on 3D printing of secondary (2°) recycled Polyvinylidene fluoride as a smart energy storage device (ESD). This work is focused on exploring the possibilities for 3D printing of smart energy storage device comprising of Polyvinylidene fluoride having (melt flow index (MFI) 30 g /(10 min) as per ASTM D 1238) reinforced with MnO2, graphite, ZnCl2, and N H 4 Cl in different weight proportions to form a feedstock filament for fused deposition modeling (FDM) in the first stage. The MFI of Polyvinylidene fluoride composites reinforced with MnO2, graphite, ZnCl2, and N H 4 Cl (34.095, 8.480, 42.982, 11.807 g /(10 min) respectively) was ascertained for possible 3D printing on FDM. The results suggest that even with an acceptable MFI of prepared 2° recycled Polyvinylidene fluoride, the same was not printable. Further for possible 3D printing on FDM, low-density polyethylene (LDPE) was blended in a Polyvinylidene fluoride matrix, and successful 3D printing-based energy storage device was prepared in the second stage. The study also highlights the mechanical, and morphological properties of Polyvinylidene fluoride composites have been improved after processing with a twin-screw extruder (TSE) by using different input parameters (screw temperature (T), screw speed (S), and load (L)). Overall, the study suggests that the proportion of LDPE, MnO2, graphite, ZnCl2, and N H 4 Cl has a significant effect on the rheological, mechanical, and morphological properties. The results have been supported with scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and Fourier-transformed infrared spectroscopy (FTIR) analysis. [ABSTRACT FROM AUTHOR]

Crohn's disease (CD) is a complex chronic inflammatory disorder with both gastrointestinal and extra-intestinal manifestations associated immune dysregulation. Analyzing 202,359 cells from 170 specimens across 83 patients, we identify a distinct epithelial cell type in both terminal ileum and ascending colon (hereon as 'LND') with high expression of LCN2, NOS2, and DUOX2 and genes related to antimicrobial response and immunoregulation. LND cells, confirmed by in-situ RNA and protein imaging, are rare in non-IBD controls but expand in active CD, and actively interact with immune cells and specifically express IBD/CD susceptibility genes, suggesting a possible function in CD immunopathogenesis. Furthermore, we discover early and late LND subpopulations with different origins and developmental potential. A higher ratio of late-to-early LND cells correlates with better response to anti-TNF treatment. Our findings thus suggest a potential pathogenic role for LND cells in both Crohn's ileitis and colitis., (© 2024. The Author(s).)

Background: When it comes to readiness to transition to an adult subspecialty clinic, perspectives between patients with inflammatory bowel disease (IBD) and their caregivers may differ and influence the ability to successfully transition. Patients with IBD have been shown to suffer from poor transfers of care. There is a need to more efficiently and accurately assess transition readiness to improve the transfer process., Methods: Patients transferring to an adult subspecialty clinic and their caregivers were each administered the Transition Readiness Assessment Questionnaire and IBD Self-Efficacy Scale-Adolescent. Differences between patient and caregiver responses and agreement among each dyad were tested., Results: There were 29 dyads of patients and caregivers who enrolled. There was no difference between patient and caregiver total scores. The average level of agreement between patients and caregivers was 78%. There was no association between patient response and their age, gender, ethnicity, age at time of transfer, age at diagnosis, or number of emergency room visits in the prior year., Conclusions: Patient-reported readiness to transition to adult care was confirmed by their caregivers using validated readiness assessment tools. As transition clinics must focus on high-yield interventions, a readiness survey of young adult patients without a survey of their caregivers may be adequate. However, as experts in each patient's journey, caregivers may be utilized when setting goals and priorities for a transition readiness program. The surveys used in this study can be used broadly to aid subspecialty clinics that are trying to improve the transition process., Competing Interests: Sarah N. Horst, MD, MPH- consultant and advisory board for Abbvie, Jannsen, USB, Takeda, and Gilead; Robin L. Dalal, MD- Consultant and advisory board for Abbvie; Baldeep Pabla, MD- Advisory board for BMS and Jannsen, Consultant for Abbvie and Ossium Health; David A. Schwartz, MD- consultant for Abbvie, Genetech, Gilead, Janssen, Pfizer, Takeda, and UCB. Dawn Beaulieu- consultant and the advisory board for Abbvie, Takeda, consultant for Bristol Myers Squibb, Celltrion, and the Institute of Functional Medicine. For the remaining authors, none is declared., (© The Author(s) 2024. Published by Oxford University Press on behalf of Crohn's & Colitis Foundation.)

Background: Longitudinal research reveals a unidirectional relationship between a nonsomatic symptom of depression, a negative view of the self, and later reported Crohn's disease (CD) activity. We evaluated whether health behaviors mediated this association using a longitudinal design., Methods: We studied 3304 adult volunteers with a self-reported diagnosis of CD who completed a baseline survey that included demographics, CD activity, a symptom-specific index of depression, and measures of physical activity, smoking, and sleep quality. Crohn's disease status and the cognitive index of depression were also measured 6 and 12 months after the baseline evaluation. We specified single-mediator and multiple-mediator models to elucidate the depression-disease activity relationship., Results: Among 2395 females and 909 males, we found a significant mediation effect for activity level ( P < .001) after adjusting for age, sex, and body mass index. There was no evidence that sleep quality and smoking are significant single mediators. When we considered multiple mediation models, smoking and less activity partially mediate the depression-CD association., Conclusions: Smoking and lower levels of physical activity are potential mediators of the unidirectional association between a nonsomatic symptom of depression-a negative view of the self-and patient-reported CD activity. Evaluating and treating specific symptoms of depression may reduce the frequency of CD exacerbations., Competing Interests: There are no conflicts of interest to disclose for all named authors. The study protocol was approved by the Institutional Review Boards at the universities where the data was collected and analyzed, respectively., (© The Author(s) 2023. Published by Oxford University Press on behalf of Crohn's & Colitis Foundation.)

For various orthopedic needs, several studies have been testified on non-absorbable implants, prepared with different metals/alloys, and composites. But yet little has been stated on the partially absorbable smart implants of thermoplastic composites for online health monitoring of veterinary patients. This article highlights the in-house development of affordable, polyvinylidene fluoride (PVDF) composite-based partially absorbable smart implants (with online sensing capability) for orthopedic needs in canines. Hydroxyapatite (HAp) and chitosan (CS) nanoparticles were reinforced in the PVDF matrix by a melt processing route with various weight proportions (wt.%) to fabricate a partially absorbable smart implant for the canine. The study suggests that the 8.0 wt.% HAp and 2.0 wt.% CS in PVDF is the superlative composition/proportion of reinforcement for preparing feedstock stock filaments (for 3D printing of partially absorbable smart implants), based on rheological, mechanical, thermal, dielectric, and voltage-current-resistance ( V - I - R ) characteristics. For the selected composition/proportion of PVDF composite, acceptable mechanical properties (such as modulus of toughness (MoT) 2.0 MPa, Young's modulus (E) 889 MPa), and dielectric properties (dielectric constant (ε r ) 9.6 at room temperature (30°C) and 20 MHz) for online sensing capabilities (for health monitoring) was observed. The results are braced by attenuated total reflection Fourier transform infrared (ATR-FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS) analysis.

Background: Vedolizumab is a monoclonal antibody used to treat inflammatory bowel disease (IBD). There is little known about the safety and comparative efficacy of this agent in the elderly population., Aims: Here, we present data on the safety and comparative efficacy of vedolizumab versus tumor necrosis factor α antagonists (anti-TNF) in elderly patients with IBD., Methods: This retrospective cohort study included IBD patients started on vedolizumab or anti-TNF at age 60 or older at a single tertiary IBD center. Safety was evaluated by assessing for the development of serious infection. The comparative needs for IBD-related surgery, IBD-related hospitalization, and drug discontinuation for any reason were obtained. Efficacy was assessed by comparing changes in endoscopic, histologic, and patient-report outcomes., Results: 212 cases were identified-108 patients treated with vedolizumab and 104 patients treated with anti-TNF. There were no significant differences between cohorts in serious infection, surgical intervention, or IBD-hospitalization-free survival (p = NS). Drug discontinuation survival was different between anti-TNF and vedolizumab (p = 0.02) with more patients remaining on vedolizumab at the time of last follow-up (51.9% vs. 25.9%). Endoscopic remission and response rates were higher in the vedolizumab versus anti-TNF group (65.7% vs. 45.2%, p = 0.02; 80.0% vs. 59.3%, p < 0.001)., Conclusions: In a cohort of IBD patients over age 60, vedolizumab showed no statistically significant differences in infection, hospitalization, or surgical intervention-free survival as compared to anti-TNF. Vedolizumab was discontinued less frequently than anti-TNF. Patients on vedolizumab had higher rates of endoscopic remission and response., (© 2021. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Background: Tofacitinib has been approved for moderate-to-severe ulcerative colitis and studied in Crohn's disease. Understanding medication adherence to oral medications in severe disease is essential., Methods: We retrospectively reviewed adherence and real-world outcomes of inflammatory bowel disease patients who initiated tofacitinib at a single care center. Adherence was measured by proportion of days covered., Results: Sixty-three patients were identified. All patients failed at least one prior biologic therapy. Mean proportion of days covered was 95.7% for ulcerative colitis and 93.1% for Crohn's disease. Significant clinical and endoscopic response was seen., Conclusion: Adherence was high in a cohort with highly refractory disease., (© The Author(s) 2021. Published by Oxford University Press on behalf of Crohn\'s & Colitis Foundation.)

Ulcerative colitis (UC) is a chronic disease that can present at various stages of disease activity and severity. Traditionally, severity scoring has focused on disease activity during a single moment with various tools, including patient-reported symptoms, as well as clinical, laboratory-based, endoscopic, histologic, and imaging variables. Optimal delivery of care depends on the accurate assessment of disease severity, which must take longitudinal variables into account. This article reviews the history of severity scoring in UC and provides a concise, clinically oriented approach to assessing disease severity., Competing Interests: Disclosure Dr B.S. Pabla has no relevant financial disclosures. Dr D.A. Schwartz has the following financial disclosures: Abbvie, consultant; UCB, consultant, grant support; Janssen, consultant; Takeda, consultant; Gilead, consultant; Pfizer, consultant; Genetech, consultant., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Background & Aims: Gastric cancer is the leading cause of infection-related cancer death and the third-leading cause of cancer death worldwide. The effect of immigration on gastric cancer risk is not well-defined but might be helpful for screening or surveillance endeavors. We performed a systematic review and meta-analysis to define the risk of gastric cancer in immigrants from high-incidence regions to low-incidence regions (including Western Europe, Australia, Brazil, Canada, Israel, and the United States)., Methods: We searched MEDLINE and EMBASE databases, from January 1980 to January 2019, for studies that identified immigrants from high-incidence regions of gastric cancer, provided clear definitions of immigrant and reference populations, and provided sufficient data to calculate gastric cancer incidence and gastric cancer-related mortality. We performed meta-analyses of standardized incidence ratios (SIR) for first-generation immigrants from high- to low-incidence regions, stratified by immigrant generation, sex, and anatomic and histologic subtype, when data were available., Results: We identified 38 cohort studies that met our inclusion criteria. All 13 studies of 21 distinct populations reported significantly increased SIRs for gastric cancer in first-generation foreign-born immigrants (men SIR range, 1.24-4.50 and women SIR range, 1.27-5.05). The pooled SIR for immigrants with all types of gastric cancer was 1.66 (95% CI, 1.52-1.80) for men and 1.83 (95% CI, 1.69-1.98) for women. Nine studies from 2 high-incidence populations (the former Soviet Union and Japan) reported an increased gastric cancer standardized mortality ratio in first-generation immigrants who migrated to regions of low incidence (former Soviet Union immigrants, 1.44-1.91 for men and 1.40-2.56 for women)., Conclusions: Immigrants from regions with a high incidence of gastric cancer to regions of low incidence maintain a higher risk of gastric cancer and related mortality, based on a comprehensive systematic review and meta-analysis. Assessment of immigrant generation along with other risk factors might help identify high-risk populations for prevention and therapeutic interventions., (Copyright © 2020 AGA Institute. Published by Elsevier Inc. All rights reserved.)

Condition monitoring systems are increasingly being employed in industrial applications to improve the availability of equipment to increase the overall equipment efficiency. Condition monitoring of gearboxes, a key element of rotating machines, ensures to continuously reduce and eliminate costs, unscheduled downtime and unexpected breakdowns. This study demonstrates a low-cost microcontroller-based non-contact data acquisition system for condition monitoring of rotating machinery. Experimental validation of the proposed system was carried out by performing examination tests on a gearbox test rig. A user-friendly graphical user interface was also developed which facilitates users to perform signal processing in both real-time and offline mode. The proposed system can perform most of the functions available in complex, stand-alone vibration analysers. The use of a general-purpose PC and standard programing language makes the system simple, economical and adaptable to a variety of problems. The tests show the developed system can perform properly as proposed., Competing Interests: We have no competing interests.

Surface integrity has attracted the attention of researchers for improving the functional performance of engineering products. Improvement in surface finish, one of the important parameters in surface integrity, has been attempted by researchers through different processes. Grinding has been widely used for final machining of components requiring smooth surfaces coupled with precise tolerances. Proper selection of grinding wheel material and grade with grinding parameters can result in an improved surface finish and improved surface characteristics. The present work reports the study of the effect of grinding parameters on surface finish of EN8 steel. Experiments were performed on surface grinding and cylindrical grinding for optimization of grinding process parameters for improved surface finish. Grinding wheel speed, depth of cut, table feed, grinding wheel material and table travel speed for surface grinding operation, and work speed for cylindrical grinding operation were taken as the input parameters with four types of grinding wheels (Al 2 O 3 of grades K and L, and white alumina of grades J and K). The surface roughness was taken as an output parameter for experimentation. The grinding wheel material and grade have been observed to be the most significant variables for both cylindrical grinding and surface grinding. Surface roughness in the case of surface grinding is better compared to that of cylindrical grinding, which can be attributed to vibrations produced in the cylindrical grinding attachment. Surface roughness ( R a ) values of 0.757 µm in cylindrical grinding and 0.66 µm in surface grinding have been achieved., Competing Interests: The authors have no competing interests.

Gearbox plays most essential role in the modern machinery for transmitting the required torque along with motion and contributes to wide range of applications. Any failure in gearbox components affects the productivity and efficiency of the system. Most machine breakdowns related to gears are a result of improper operating conditions and loading, hence lead to failure of the whole mechanism. Ensemble Empirical Mode Decomposition (EEMD) comprises advancement and valuable addition in Empirical Mode Decomposition (EMD) and has been widely used in fault detection of rotating machines. However, intrinsic mode functions (IMFs) produced by EEMD often carry the residual noise. Also, the produced IMFs are different in number due to addition of white Gaussian noise, which leads to final averaging problem. To alleviate these drawbacks, Complete Ensemble Empirical Mode Decomposition with Adaptive Noise (CEEMDAN) was previously presented. This paper describes and presents the implementation of CEEMDAN for fault diagnosis of simulated local defects using sound signals in a fixed-axis gearbox. Statistical parameters are extracted from decomposed sound signals for different simulated faults. Results show the effectiveness of CEEMDAN over EEMD in order to obtain more accurate IMFs and fault severity., Competing Interests: We have no competing interests.