bluuebunny/crossref_metadata_2025 huggingface dataset:
Ultimate bending performance and fatigue life of U-shaped metal bellows
Authors: Hao Zengliang , Chen Yuhang , Chen Lihuan , Cai Yi , Luo Junting
Published: May 2022

Metal bellows used in the flexible connection of metallurgical converter oxygen lance compensates for pipeline displacement through its bending deformation, and adjacent waveforms in the concentrated deformation area are squeezed, resulting in premature fracture. The bending geometric model of U-shaped metal bellows is established in this paper, and the geometric relationship between waveform structure parameters and ultimate bending radius is derived. Moreover, a mathematical model of bending moment (M) with bending angular displacement (θ) about wave height H and wave crest fillet radius Rc is established. Then, combined with Fe-safe fatigue life analysis software, the fatigue life and failure location of metal bellows are obtained. The optimal waveform parameter design range of DN80 metal bellows with high repeated bending fatigue life under large bending is determined. Finally, the bending performance and fatigue life of bellows are tested on a bending fatigue testing machine. The distribution law of fatigue life and the propagation law of cracks at the wave trough of metal bellows under different bending angular displacement amplitudes are obtained. The crack propagation mechanism and fracture mechanism under different displacement amplitudes are revealed by a scanning electron microscope. In the engineering application of large bending, the pipeline failure caused by the ultimate bending deformation of metal bellows can be avoided according to the prediction results of fatigue life.
Prevalence of and factors associated with anal high-risk human papillomavirus in urban Tanzanian men who have sex with men, 2011-2012
Authors: Nyitray Alan G , Masunaga Ka ` imi  ` aina , Nyoni Joyce , Ross Michael W
Published: May 2022

Background: Anal cancer is primarily caused by high-risk human papillomavirus (hrHPV), is associated with HIV infection, and has a very high incidence among men who have sex with men (MSM). We assessed prevalence of hrHPV, and factors associated with hrHPV in anal canal specimens collected in Dar es Salaam, Tanzania from HIV-positive and HIV-negative MSM. Methods: MSM were recruited using respondent-driven sampling in this cross-sectional study. The primary outcome in this ancillary analysis of 116 MSM was prevalence of HPV-16 and other hrHPV types. Prevalence ratios (PR) estimated the association between hrHPV and HIV-negative participants’ demographics, sexual behaviour and sexually transmitted infections. Results: Median age was 23 years and 33.6% of participants were HIV-positive. HrHPV and HPV-16 prevalence was 54.3% and 17.2%, respectively, with HPV-16 prevalence highest among HIV-positive MSM identifying as gay (36.1%) and lowest among HIV-negative MSM identifying as bisexual (2.9%). Having two or more receptive anal sex partners in the past month was associated with hrHPV (PR 3.20, 95%CI 1.69-6.07, vs. 0 partners) among HIV-negative MSM.Conclusions: HrHPV prevalence was high among MSM in Dar es Salaam and highest among HIV-positive MSM identifying as gay. These estimates may be used to support HPV vaccination and screening initiatives.
Effect of the hub cavity leakage on the aerodynamic performance and strength characteristics of the 150 kW SCO2 centrifugal compressor
Authors: Cao Run , Li Zhigang , Deng Qingua , Li Jun , Gao Tieyu
Published: May 2022

The hub cavity leakage has large effect on the aerodynamic performance on the Supercritical carbon dioxide (SCO2) centrifugal compressor. In this paper, the aerodynamic performance and strength characteristics of the 150 kW SCO2 centrifugal compressor with the hub cavity were numerically investigated using three-dimensional Reynolds-Averaged Navier-Stokes (RANS) and [Formula: see text] turbulence model. The high precision physical properties tables of SCO2 were used to calculate the SCO2 property parameters across the centrifugal compressor flow passages. The aerodynamic performance of the 150 kW SCO2 centrifugal compressor without and with the hub cavity and the labyrinth seal at different mass flow coefficients was compared. The equivalent (von-Mises) stress and the deformation on the SCO2 centrifugal impeller were obtained by the combination of the aerodynamic pressure and centrifugal force calculation. The results show that the isentropic efficiency of the SCO2 centrifugal compressor without and with the hub cavity and the labyrinth seal at the designed flow coefficient equal 73.2% and 72.1% respectively. The effects of the hub cavity leakage on the pressure ratio of the SCO2 centrifugal compressor are limited. The hub cavity leakage decreases with the flow coefficient increasing. The similar isentropic efficiency of the SCO2 centrifugal compressor without and with the hub cavity and the labyrinth seal at the largest flow coefficient is obtained. The axial thrust of the SCO2 centrifugal compressor with the hub cavity and the labyrinth seal ranges from 1000N to 2000N at different flow coefficients, as well as keeps the same direction. The maximum equivalent (von-Mises) stress of the impeller is 109.95 MPa and less than the allowable stress 137 MPa (using 304 steel as the impeller material). The maximum deformation of the seal teeth is less than 0.003 mm. This work provides the reference of the compressor design and safety operation for the SCO2 centrifugal compressor.
Ryanair pilots: Unlikely pioneers of transnational collective action
Authors: Golden Darragh , Erne Roland
Published: May 2022

In aviation, EU single market rules empowered Ryanair over three decades to defeat all pilot unions across Europe, regardless of the notionally strong power resources on which they were relying in their countries. Nonetheless, in December 2017, a transnational group of union-related pilots, the European Employee Representative Committee was critical in forcing Ryanair to finally recognize trade unions. This study shows that multinationals’ ability to circumvent national union power resources does not necessarily undermine transnational collective action. Hence, transnational union strength does not primarily depend on an aggregation of national power resources, but on union activists’ ability to exploit union-friendly peculiarities that the EU governance regime is also providing. We show that the apparently weaker institutional power resources at EU level provides more effective leverage for transnational collective action than apparently stronger power resources embedded within French, Danish, or Norwegian labour law. This requires an understanding of scale.
Using current research information systems to investigate data acquisition and data sharing practices of computer scientists
Authors: Rousi Antti Mikael
Published: May 2022

Without sufficient information about research data practices occurring in a particular research organisation, there is a risk of mismatching research data service efforts with the needs of its researchers. This study describes how data acquiring and data sharing occurring within a particular research organisation can be investigated by using current research information system publication data. The case study organisation’s current research information system was used to identify the sample of investigated articles. A sample of 193 journal articles published by researchers in the computer science department of the case study’s university during 2019 were extracted for scrutiny from the current research information system. For these 193 articles, a classification of the main study types was developed to accommodate the multidisciplinary nature of the case department’s research agenda. Furthermore, a coding framework was developed to capture the key elements of data acquiring and data sharing. The articles representing life sciences and computational research relatively frequently reused open data, whereas data acquisition of experimental research, human interaction studies and human intervention studies often relied on collecting original data. Data sharing also differed between the computationally intensive study types of life sciences and computational research and the study types relying on collection of original data. Research data were not available for reuse in only a minority of life science ( n = 2; 7%) and computational research ( n = 15; 14%) studies. The study types of experimental research, human interaction studies and human intervention studies less frequently made their data available for reuse. The findings suggest that research organisations representing computer sciences may include different subfields that have their own cultures of data sharing. This study demonstrates that analyses of publications listed in current research information systems provide detailed descriptions how the affiliated researchers acquire and share research data.
Delivering services in the new normal: Recording the experiences of UK public library staff during the COVID-19 pandemic
Authors: Robinson Elaine , Ruthven Ian , McMenemy David
Published: May 2022

This paper reports the results of a survey undertaken in December 2021 and January 2022 related to public library staff in the United Kingdom and their experiences of COVID-19, exploring the lockdowns that were enabled, the subsequent re-openings, their mental health and their views for the future of the service post-COVID-19. Over 200 responses were received, and the findings indicate a range of views. The importance of the library as a community resource is evident in the comments from staff, and their observations of patrons on library re-openings. Findings also indicate concern for the future of the library service, and fear that new technologies like e-books may be seen as adequate replacements for the traditional library service. Findings also indicate staff face stress and mental health issues in terms of dealing with patrons while the virus remains highly prevalent.
Point of view: Could social media use be contributing to rising rates of deliberate self-harm and suicide in Australian youth populations?
Authors: Webb Beatrice , Looi Jeffrey CL , Allison Stephen , Bidargaddi Niranjan , Bastiampillai Tarun
Published: May 2022

Objective

A rapid clinical update on the potential interplay between social media use and rates of deliberate self-harm amongst young people in Australia.

Conclusions

Rising social media use has been associated with increasing cyberbullying and deliberate self-harm, especially in young women. On the other hand, social media use also provides beneficial support. Examination of problematic social media use in assessments of young people presenting with self-harm may be useful, along with discussion of responses to negative social media. In this point of view, we discuss these matters and the UK Royal College of Psychiatrists’ recommendations for reducing the negative impact of social media.
Intoxication of llamas by Astragalus punae in Argentina
Authors: Marin Raul E. , Gardner Dale R. , Armien Anibal G. , Fortunato Renée H. , Uzal Francisco A.
Published: May 2022

Several plants that contain indolizidine alkaloids, including swainsonine, are toxic to livestock, causing dysfunctional lysosomes and storage disease. Swainsonine induces a neurovisceral disease, known as locoism, in sheep, goats, and cattle, which occurs in several parts of the world, including, but not limited to, the western United States, China, and parts of Australia. In South America, locoism has been described in the Andean region of Argentina affecting sheep, cattle, and llamas. Intoxication by consumption of Astragalus punae was suspected in 4 llamas in Jujuy Province, northwestern Argentina. The grazing area contained abundant specimens of A. punae. The clinical course was ~15 d, and included moderate ataxia, incoordination of hindlimbs, and progressive loss of body condition. Microscopically, fine cytoplasmic microvacuolation was observed in the proximal convoluted renal tubules. Ultrastructurally, these changes consisted of severely dilated lysosomes. Swainsonine was detected in stem and leaf samples of A. punae at a concentration of 0.06%. Based on clinical history and signs, histologic and ultrastructural changes, and plant analysis, a diagnosis of swainsonine toxicosis caused by consumption of A. punae was made, which has not been reported previously, to our knowledge.
The Long-Run Effects of Communism and Transition to a Market System on Self-Employment: The Case of Germany
Authors: Fritsch Michael , Greve Maria , Wyrwich Michael
Published: May 2022

We investigate how self-employment in East Germany was impacted by 40 years of Soviet-style communism and the subsequent shock transition to a market economic system. To this end, we compare self-employment in East and West Germany after reunification with self-employment before the separation of Germany after World War II. Our results show that the strict anti-entrepreneurial policies prevalent during the Soviet regime do not have a long-run negative effect on self-employment in East Germany. Quite to the contrary, self-employment in East Germany today is higher than before German separation. This finding cannot be explained by necessity self-employment. Our analysis suggests that current differences in self-employment between East and West Germany are pre-dominantly a result of the sudden shock transformation that occurred with reunification, rather than the outcome of four decades of anti-entrepreneurial policies and ideology.
Coping Skills Interventions for Fatigue in Adults with Hematologic Malignancies: A Systematic Review
Authors: Andersen Lucy , McHugh Molly , Ulrich Connie , Meghani Salimah , Deng Jie
Published: May 2022

Background: Persons with hematologic malignancies have a high symptom burden throughout the illness journey. Coping skills interventions effectively reduce fatigue for other cancer patients. The purpose of this systematic review is to identify if coping interventions can reduce fatigue in patients with hematologic malignancies. Methods: A search of PubMed, Embase, CINAHL, APA Psych INFO, Scopus, Cochrane, and non-traditional publications was performed in June 2021 for studies introducing coping interventions for adults with hematological cancers within the past 20 years. The Transactional Model of Stress and Coping was used as a framework with fatigue as the primary outcome. The Johns Hopkins Nursing Evidence Based Practice Appraisal tool was used for quality appraisal. Results: Twelve interventional studies met criteria for inclusion. Four studies significantly reduced fatigue, with an additional 3 showing a reduction in fatigue. Interventions that utilized both problem and emotion-focused coping were more effective at reducing fatigue compared to interventions that only used emotion or problem-focused coping. Conclusion: This systematic review found moderate-strength evidence to support that coping interventions can reduce fatigue, with mixed, but mostly beneficial results. Clinicians caring for patients with hematologic malignancies should consider using coping interventions to reduce fatigue.
Effectiveness of damping and inertance of two dampers on mitigation of multimode vibrations of stay cables by using the finite difference method
Authors: Wang Yuanyuan , Li Shouying , Qie Kai , Zhou Shuai , Chen Zhengqing
Published: May 2022

Stay cables of several cable-stayed bridges with a span of nearly 1000 m are confronted with the simultaneous actions of low-mode rain-wind induced vibration and high-mode vortex-induced vibration. It is difficult to effectively reduce these two kinds of cable vibrations by installing one damper at the end of the stay cable. In this paper, the effectiveness of two dampers attached at the lower end of the stay cable, including viscous dampers and viscous inertial mass dampers, is investigated by the finite difference method. First, the stay cable was simplified as an inclined cable with sag, and equation of motion governing the stay cable attached with two dampers was derived. This equation was then numerically solved by the finite difference method. Second, taking Cable A30 of the Suzhou-Nantong Yangtze River Bridge as a reference, a series of numerical simulations were carefully conducted to obtain the damping ratios of the first fifty modes. The results show that it is impossible to enhance the damping ratios of all of the concerned modes up to the minimum target value only by installing a single viscous damper or a single viscous inertial mass damper at the end of the stay cable. However, two viscous dampers installed at the lower end of the cable ( l1/ l = 2%, l2/ l = 5%) can overcome the shortcoming of a single viscous damper or viscous inertial mass damper to enhance the damping ratios of the first 34 modes up to the minimum target value (0.5%). In general, the optimized relative location of the two dampers ( l2/ l1) should be near 2. The optimized ratio of the damping coefficients ( η1/ η2) should be lower than l2/ l1, and the lower limit of η1/ η2 is determined by the minimum target values for modal damping ratios. Moreover, it appears that a lower installation position of two viscous dampers can realize the mitigation of higher modes even up to the 40th ∼ 50th modes.
Novel low frequency bionic vibration isolation structure
Authors: Shi Xiaojie , Xu Jin , Chen Tingkun , Cong Qian , Tian Weijun
Published: May 2022

Inspired by the hind limbs of goats, a bio-inspired polygon vibration isolation structure with nonlinear stiffness and damping is proposed. The bionic mechanism consists of four bionic legs with different rods (as skeleton), 12 inclined tension springs (as muscle or tendon), a bearing platform, a base, and so on. A theoretical model is developed to characterize its stiffness nonlinearity through geometrical and mechanical analysis. Theoretical analysis shows that the bionic structure has nonlinear positive stiffness and large working range. The dynamic model of the structure is established based on the Lagrange principle, and the influence of various structural parameters on the vibration isolation performance of the structure was analyzed combined with ADAMS. Thanks to the unique bionic design, the device allows the stiffness and damping characteristics of the system to be adjusted by varying the structural parameters, resulting in excellent stability, high static and low dynamic stiffness, excellent vibration isolation performance, and good load carrying capacity without active control.
Prospective Associations Between Early Childhood Intimate Partner Violence Exposure and Middle Childhood Internalizing and Externalizing Psychopathology
Authors: Lee Amy Hyoeun , Mirhashem Rebecca , Bernard Kristin , Dozier Mary
Published: May 2022

Co-occurring adversities are common for young children with child protective services (CPS) involvement, with high rates of intimate partner violence (IPV) exposure in this population. Despite extensive research linking childhood IPV exposure to later psychopathology, fewer studies have examined the prospective associations between IPV exposure and psychopathology using a dimensional approach. Here, we conducted secondary analyses of data from a randomized controlled trial of a parenting intervention for CPS-involved children, examining the associations between early childhood IPV exposure (i.e., threat), co-occurring deprivation, and middle childhood internalizing and externalizing symptoms. Adversity variables were coded from data collected when children were infants ( N = 249, M age = 7.97 months) through 48-month assessments; internalizing and externalizing psychopathology were modeled as latent variables reflecting the mean of data from yearly assessments between ages 8 to 10. Results of our structural equation model demonstrated that, accounting for the effects of co-occurring deprivation, IPV exposure was significantly associated with both internalizing, β = .38, p = .001, and externalizing, β = .26, p = .019, symptoms. Results suggest links between early childhood IPV exposure (i.e., threat) and later psychopathology. Findings support screening and intervention efforts to mitigate the developmental sequelae of IPV exposure among CPS-involved children.
On waves in multi-scale chiral elastic systems
Authors: Movchan Alexander B , Movchan Natalia V , Jones Ian S
Published: May 2022

The paper addresses the question of the dynamic chirality in vibrating elastic systems. An overview of continuous and discrete models is presented with the focus on phenomena, associated with the rotational motion, which are absent in classical non-chiral media. The time dependence is essential for the models discussed in this paper—the effects attributed to the dynamic chirality do not occur in the case of static elastic deformations. A formal connection is also drawn between the mathematical formulations for a class of elastic waves in chiral systems and electromagnetic waves in magnetised media. Both continuum and discrete systems, analysed in the context of the wave localisation and dispersion, are discussed here.
The universal program of linear elasticity
Authors: Yavari Arash , Goriely Alain
Published: May 2022

Universal displacements are those displacements that can be maintained, in the absence of body forces, by applying only boundary tractions for any material in a given class of materials. Therefore, equilibrium equations must be satisfied for arbitrary elastic moduli for a given anisotropy class. These conditions can be expressed as a set of partial differential equations for the displacement field that we call universality constraints. The classification of universal displacements in homogeneous linear elasticity has been completed for all the eight anisotropy classes. Here, we extend our previous work by studying universal displacements in inhomogeneous anisotropic linear elasticity assuming that the directions of anisotropy are known. We show that universality constraints of inhomogeneous linear elasticity include those of homogeneous linear elasticity. For each class and for its known universal displacements, we find the most general inhomogeneous elastic moduli that are consistent with the universality constrains. It is known that the larger the symmetry group, the larger the space of universal displacements. We show that the larger the symmetry group, the more severe the universality constraints are on the inhomogeneities of the elastic moduli. In particular, we show that inhomogeneous isotropic and inhomogeneous cubic linear elastic solids do not admit universal displacements and we completely characterize the universal inhomogeneities for the other six anisotropy classes.
Analysis of radial expansion, eversion, and cavitation of soft functionally graded material spheres
Authors: Mousavi S Ali , Bahrami Arash , San Omer , Batra Romesh C
Published: May 2022

We study radial expansion, cavitation, and eversion of spherical shells made of incompressible, isotropic, and functionally graded (i.e. inhomogeneous) soft (or rubber-like) materials that are increasingly being used in prosthetics, seals, tires, flexible electronics, soft robots, and many other applications. We consider all geometric and material nonlinearities and assume the sphere material to be Mooney–Rivlin material whose two parameters, C1( R) and C2( R), are smooth functions of the radial coordinate, R, in the stress-free undeformed configuration. The shell’s inversion illustrates non-uniqueness of solutions in finite elasticity since sphere’s bounding surfaces are traction free in the reference and the deformed configurations but stresses/strains in the interior are different. Assuming that a shell under a dead tensile pressure on the outer surface cavitates when the radial stretch at the inner surface equals four, we delineate effects of functions C1( R) and C2( R) on the cavitation pressure. It is found that for power-law variations with indices m and n, respectively, for C1( R) and C2( R) the cavitation pressure can be controlled by suitably choosing m and n. Large positive and negative values of m and n are deleterious for a sphere loaded only by a pressure on the inner surface since they produce high hoop stresses within the sphere. Other results given in the paper will enable one to tailor functions C1( R) and C2( R) to either mitigate cavitation or initiate it at a desired pressure or have prescribed through-the-thickness variations of stresses to optimize sphere’s performance.
Elastodynamics of a coated half-space under a sliding contact
Authors: Bratov V , Kaplunov J , Lapatsin SN , Prikazchikov DA
Published: May 2022

The paper deals with elastic wave propagating in a layer on a half-space induced by a vertical force. The focus is on the effect of a sliding contact along the interface and its comparative study with a perfect one. The effective boundary conditions substituting the presence of the layer are derived. The leading order term in these conditions corresponds to vertical inertia of the layer, whereas next order correction involves the effect of plate waves in the coating. Analysis of the associated dispersion relation confirms the existence of a Rayleigh-type wave, along with extensional and shear plate waves. An asymptotic hyperbolic-elliptic formulation for surface wave field is also presented. This includes a hyperbolic equation singularly perturbed by a pseudo-differential operator playing a role of a boundary condition for the elliptic equation governing decay over the interior. The sign of the coefficient at the pseudo-differential operator is demonstrated to be always negative, corresponding to a local maximum of the phase speed at zero wave number, and consequently to a distinct receding type of the Rayleigh-type wave quasi-front induced by an impulse load.
Real-form solution for an anisotropic elastic elliptical inhomogeneity under uniform heat flux
Authors: Wang Xu , Schiavone Peter
Published: May 2022

We use the extended Stroh sextic formalism for thermo-anisotropic elasticity to present an elegant solution of the problem of an anisotropic elastic elliptical inhomogeneity embedded in an infinite anisotropic elastic matrix subjected to uniform remote heat flux. We prove rigorously that the remote thermal stresses cannot be set to zero in a generally anisotropic elastic matrix. In particular, a real-form solution is derived for the internal thermoelastic field describing stresses, strains, and displacements within the elliptical inhomogeneity.
Very fast finite element Poisson solvers on lower precision accelerator hardware: A proof of concept study for Nvidia Tesla V100
Authors: Ruda Dustin , Turek Stefan , Ribbrock Dirk , Zajac Peter
Published: May 2022

Recently, accelerator hardware in the form of graphics cards including Tensor Cores, specialized for AI, has significantly gained importance in the domain of high-performance computing. For example, NVIDIA’s Tesla V100 promises a computing power of up to 125 TFLOP/s achieved by Tensor Cores, but only if half precision floating point format is used. We describe the difficulties and discrepancy between theoretical and actual computing power if one seeks to use such hardware for numerical simulations, that is, solving partial differential equations with a matrix-based finite element method, with numerical examples. If certain requirements, namely low condition numbers and many dense matrix operations, are met, the indicated high performance can be reached without an excessive loss of accuracy. A new method to solve linear systems arising from Poisson’s equation in 2D that meets these requirements, based on “prehandling” by means of hier-archical finite elements and an additional Schur complement approach, is presented and analyzed. We provide numerical results illustrating the computational performance of this method and compare it to a commonly used (geometric) multigrid solver on standard hardware. It turns out that we can exploit nearly the full computational power of Tensor Cores and achieve a significant speed-up compared to the standard methodology without losing accuracy.
Inflammatory, Oxidative Stress, and Cardiac Damage Biomarkers and Radiation-Induced Fatigue in Breast Cancer Survivors
Authors: Vasbinder Alexi , Thompson Hilaire , Zaslavksy Oleg , Heckbert Susan R. , Saquib Nazmus , Shadyab Aladdin H. , Chlebowski Rowan T. , Warsinger Martin Lisa , Paskett Electra D. , Reding Kerryn W.
Published: May 2022

Purpose

Studies examining biomarkers associated with fatigue in breast cancer survivors treated with radiation are limited. Therefore, we examined the longitudinal association between serum biomarkers and post-breast cancer fatigue in survivors treated with radiation: [oxidative stress] 8-hydroxyguanosine, myeloperoxidase; [inflammation] interleukin-6 (IL-6), c-reactive protein, growth differentiation factor-15 (GDF-15), placental growth factor, transforming growth factor-beta, [cardiac damage] cystatin-C, troponin-I.

Methods

In a secondary analysis, we included participants from the Women’s Health Initiative if they had: a previous breast cancer diagnosis (stages I-III), no prior cardiovascular diseases, pre-and post-breast cancer serum samples drawn approximately 3 years apart, and fatigue measured using the Short-Form 36 vitality subscale at both serum collections. Biomarkers were measured using ELISA or RT-qPCR and modeled as the log2 post-to pre-breast cancer ratio.

Results

Overall, 180 women with a mean (SD) age of 67.0 (5.5) years were included. The mean (SD) vitality scores were 66.2 (17.2) and 59.7 (19.7) pre- and post-breast cancer, respectively. Using multivariable weighted linear regression, higher biomarker ratios of cystatin-C, IL-6, and GDF-15 were associated with a lower vitality score (i.e., higher fatigue). For example, for each 2-fold difference in cystatin-C biomarker ratio, the vitality score was lower by 7.31 points (95% CI: −14.2, −0.45).

Conclusion

Inflammatory and cardiac damage biomarkers are associated with fatigue in breast cancer survivors treated with radiation; however, these findings should be replicated in a larger sample. Biomarkers could be measured in clinical practice or assessed in risk prediction models to help identify patients at high risk for fatigue.
Investigative study of hemodilution ratio: 4Vs for vein diameter, valve, velocity, and volumetric blood flow as factors for optimal forearm vein selection for intravenous infusion
Authors: Foor John S , Moureau Nancy L , Gibbons David , Gibson S Matthew
Published: May 2022

Background:

Multimodal research and guidelines recognize veins in the forearm used for peripheral intravenous catheter (PIVC) insertion can optimize dwell time. Yet, many PIVCs are still placed in areas of flexion or suboptimal locations such as the back of the hand causing premature failure of >50%. This study identified characteristics of the forearm cephalic vein that make the anatomical location highly successful for PIVC insertion. The goal was to increase the understanding of the human vasculature in association with fluid mechanics in veins above the wrist and below the antecubital fossa.

Methodology:

A prospective in-vivo study with 10 consented healthy human volunteers (HHVs) was performed with Color Pulse Wave Doppler Ultrasound that captured high-resolution video and images of vein diameter, velocity of blood flow, and location of venous valves in the forearm.

Results:

Forearm vein diameter was not directly correlated with higher or lower Velocity of Blood Flow (0.58 cm = 3.0 cm/s). However, Volumetric Blood Flow rates tended to be lower (2.51–8.28 mL/min) with Vein Diameters smaller than 0.29 cm. Ultrasound assessments and Volumetric Blood Flow calculations confirmed natural turbulence in blood and retrograde blood reflux correlated with venous valves opening and closing. Areas of turbulence, with pulse flushing, created backflow with retrograde blood flow around and into the catheter.

Conclusions:

Placement of long PIVCs in the cephalic veins of the upper forearm yield adequate flow and hemodilution capacity for veins with at least a 3 to 1 hemodilution ratio. The data from this study, along with previous research, suggest that PIVC placement in the cephalic vein, based on selection criteria, may help to reduce or eliminate intravenous complications such as chemical or mechanical thrombophlebitis causing premature catheter failure. Application of these investigational principles may result in better outcomes and catheter longevity for patients who require intravenous infusions.
A systematic review of right atrial bypass grafting in the management of central venous occlusive disease in patients undergoing hemodialysis
Authors: Paik Benjamin , Tee Zi Heng , Masuda Yoshio , Choong Andrew MTL , Ng Jun Jie
Published: May 2022

Introduction:

Central venous occlusive disease (CVOD) is a complication that can occur in patients with end-stage renal disease who are receiving hemodialysis. When CVOD develops, patients often require multiple re-interventions to maintain their dialysis access. CVOD can be treated by various strategies such as balloon angioplasty, stenting, lower limb or extra-anatomical grafts, hybrid grafts or surgical bypasses such as right atrial (RA). In this systematic review, we aim to evaluate the indications, technical aspects, and outcomes after RA bypass grafting for the treatment of CVOD in hemodialysis patients.

Methods:

A systematic and comprehensive literature search was conducted using various electronic databases. We included articles that reported described and reported outcomes of RA bypass grafting for the treatment of CVOD in hemodialysis patients. A narrative review of the indications and technical aspects of RA bypass grafting was performed. We also pooled and reported the primary patency, secondary patency, postoperative complications, and 30-day mortality of RA bypass grafting.

Results:

A total of 21 studies with 55 patients who underwent RA bypass grafting were included in our systematic review. Follow-up period ranged from 0.5 to 84 months. The mean pooled primary patency and secondary patency of RA bypass grafting were 8.1 ± 4.9 and 21.7 ± 20.1 months, respectively. The incidence of early postoperative complications such as surgical site infection, bleeding, and access thrombosis was 0%, 4%, and 4%, respectively. The overall 30-day mortality was 4%.

Conclusions:

This systematic review summarizes the patient characteristics, technical features and outcomes of RA bypass grafting in the treatment of hemodialysis-related CVOD. RA bypass grafting may be a viable last-resort option when less invasive or conventional treatment options have been exhausted.
Adherence to healthy dietary pattern is associated with lower risk of multiple sclerosis
Authors: Keykhaei Fatemeh , Norouzy Somayeh , Froughipour Mohsen , Nematy Mohsen , Saeidi Morteza , Jarahi Lida , Amiri Fatemeh , Malek Ahmadi Mahsa , Norouzy Abdolreza
Published: May 2022

Background

Different studies have confirmed the role of nutritional factors in the etiology of Multiple sclerosis (MS). However, dietary patterns associated with the risk of MS remain unknown.

Objectives

This study aimed to investigate the possible relationship between the existing dietary patterns and the risk of MS.

Methods

This case-control study was conducted in Mashhad city, Iran in 2015. In total, 197 MS patients and 200 control subjects (matched in terms of age, gender, education level, and body mass index) were enrolled in this study. The required data were collected through interviews and questionnaire completion. Moreover, the data on the usual dietary intake of each participant during the past year were evaluated using a valid and reliable semi-quantitative food frequency questionnaire (160 items). Logistic regression analysis was applied to discover the associations between dietary patterns and the risk of MS.

Results

Four major dietary patterns were identified in this study, including Unhealthy, Western, Healthy, and Traditional. After adjustment for smoking habits, the family history of autoimmune diseases and the duration of breastfeeding, the highest tertile of Healthy dietary pattern was found to be associated with the reduced risk of MS by 74% (OR = .26; P < .001), whereas the Unhealthy dietary pattern was associated with a three-fold increased risk of MS (OR = 3.04; P < .001). However, no correlation was observed between the Western and Traditional dietary patterns and the risk of MS.

Conclusion

According to the results of this study, a healthy diet may reduce the risk of MS, whereas an unhealthy dietary pattern may.
Determining Prevalence of Depression and Covariates of Depression in a Cohort of Multiple Sclerosis Patients
Authors: Tardo Lauren M. , McCreary Morgan , Majeed Harris , Greenberg Benjamin M.
Published: May 2022

Background

Depression is one of the most common symptoms experienced by multiple sclerosis patients and may be secondary to the disease itself as well as other variables such as age, disease severity and side effects of treatment.

Objective

To determine if there is an association between disease modifying therapies and depression rates based on PHQ9 scores in multiple sclerosis.

Methods

This was a retrospective chart review. Patients followed at the University of Texas Southwestern Multiple Sclerosis and Neuroimmunology Clinic from 2017 to 2020 were included in this study. Patients’ most recent PHQ-9 scores were used. The following data was extracted from patient charts: disease modifying therapy, age, disease duration, gender, antidepressant use and ambulatory status.

Results

Data from our study included 2611 individual PHQ-9 scores. The majority of our patients were female and the mean age across all treatment groups was 50.37 years old. The median disease duration across all treatment groups was 12.74 years. Most patients in this cohort required no ambulatory assistance. 43.86% of patients were on antidepressants and use was correlated with a higher PHQ9 score. The median PHQ 9 score across all treatment groups was 4 (Interquartile range = 7). Across treatment groups, patients on interferon therapy had the lowest PHQ 9 scores with a median of 2.

Conclusions

Our study demonstrated that there were lower PHQ-9 scores among interferon treatment group as compared to other disease modifying therapies and non-treatment groups
Neonatal stress and behavior problems in preschool children born preterm
Authors: Cassiano Rafaela GM , Gaspardo Claudia M , Linhares Maria BM
Published: May 2022

The aim of the present longitudinal study was to examine the effect of preterm childbirth, acute neonatal stress, and child behavior at 18–36 months of age on later behavior outcomes in 4-5-year-old children. The sample comprised of 70 children who were born preterm. The neonatal characteristics of children were assessed during hospitalization by reviewing their medical records and utilizing the Neonatal Infant Stressor Scale. Behavior problems were evaluated by the maternal-report in the Child Behavior Checklist 1½-5 years. A multiple linear regression analysis was conducted. Also, the repeated measures analysis of variance and the McNemar test for paired samples were performed. Daily exposure of the infants to high neonatal acute stress during NICU hospitalization and more behavior problems at 18–36 months of age was associated with more total and externalizing behavior problems at 4–5 years of age. Lower gestational age at childbirth and more internalizing behavior problems at 18–36 months was associated with more internalizing problems at 4–5 years old. The present study showed the combination of predictors of neonatal conditions and behavioral problems at childhood, highlighting the relevance of the implementation of developmental care in the NICU and follow-up the preterm infants after discharge programs.
Improved four-level criteria for reliability assessment of timber components subjected to decay
Authors: Lu Weijie , Qiu Hongxing , Tian Panpan , Gu Junyang
Published: May 2022

Safety evaluation of existing timber structures is of paramount importance for making reliable and timely decisions on repair actions. Among the inspection items, biological decay is a key factor that seriously affects the structural performance of timber components. Given the unclear limits of safety grades in the existing assessment criteria and the increased reliability requirements by the latest Chinese code GB50068-2018, improved four-level criteria are proposed to update the grading rules for timber components subjected to decay. The criteria are developed by probabilistic models and limit state functions with the depth of decay as a key variable. The revised target reliability index and load partial coefficients are taken into account. The JC method and importance sampling method are applied to obtain the relationship between the reliability index and the relative depth of decay under various load conditions. The proposed four-level criteria give explicit grading rules for the safety evaluation of decayed timber components and satisfy the revised reliability requirements. It is suggested that the ratio of the decayed area to the whole cross-section ρcr is set to be 0, 5.58%, and 8.36% for main flexural components; 0, 7.40%, and 11.92% for main tension components; 0, 5.91%, and 8.61% for main compression components as limits between au and bu, bu and cu, cu and du.
Immediate solution for fractional nonlinear oscillators using the equivalent linearized method
Authors: El-Dib Yusry O
Published: May 2022

The existence of the derivative with a fractional-order in a class of differential equations could lead to complicating the analysis. In this paper, a novel approach has been introduced to facilitate the analysis of the oscillation having fractional-order derivatives and to obtain the analytical solution easily. The present technique is formulated to provide an easy way of understanding. The suggested technique has been utilized to study two examples for illustration. The similitude between the analytical and numerical solution verifies and gives satisfactory precision to the equivalent solution. The new technique is represented to be the best tool for solving the nonlinear oscillation problems in physics and engineering which have a fractional-order.
Unveiling the antecedents of senior citizens′ behavioural intentions to travel: A mixed-method approach
Authors: Hajra Vandita , Aggarwal Arun
Published: May 2022

The purpose of this study is to develop and validate a multi-dimensional scale on factors affecting senior citizens’ behavioural intentions to travel in terms of approach and avoidance. The study is longitudinal in nature and has used a mixed-method approach (qualitative and quantitative) to collect and confirm a series of indicators concerning the different constructs. Under study 1, a pool of items was generated by conducting industry expert survey and reviewing the existing literature. Afterwards, Exploratory Factor Analysis (EFA) was performed for extracting the distinct factors. Under study 2, Confirmatory Factor Analysis (CFA) was performed to validate the proposed scale. The results of EFA and CFA revealed six dimensions of push factors, three dimensions of pull factors, two dimensions of perceived travel risks, three dimensions of perceived travel constraints and two dimensions of behavioural intentions of senior citizen tourists. Under pull factors, two additional dimensions were found, namely, familiarity and friendliness quotient of a destination as well as health safety and security quotient of a destination and under perceived travel constraints, outbreak of COVID-19 has been identified as a novel structural constraint. Since there is very limited research on senior citizens’ behavioural intentions to travel, the current study adds to the body of knowledge by identifying the additional factors that affect the same. Further, the study develops and validates the items through qualitative and quantitative analysis.
A method for structural monitoring of multispan bridges using satellite InSAR data with uncertainty quantification and its pre-collapse application to the Albiano-Magra Bridge in Italy
Authors: Farneti Elisabetta , Cavalagli Nicola , Costantini Mario , Trillo Francesco , Minati Federico , Venanzi Ilaria , Ubertini Filippo
Published: May 2022

Synthetic Aperture Radar Interferometry (InSAR) using satellite data is revealing a promising tool for monitoring long-term deformation phenomena in critical infrastructural systems. Nevertheless, its use in structural engineering is still quite limited and a general understanding of its potential is still missing, especially when dealing with bridge structures for which specific methods of data processing and displacement assessment with error quantification need to be developed, accounting for the type of deformation phenomena and for the orientation of the bridge. In order to partly fill this research gap, this paper proposes a post-processing methodology to derive two-dimensional displacement configurations of multi-span bridges with properly defined error bounds, using both ascending and descending Synthetic Aperture Radar acquisitions. In order to obtain an engineering meaningful estimate of the uncertainties affecting the reconstructed bridge deformations, both random and systematic errors are quantified, accounting for the orientation of the bridge with respect to the Line-Of-Sights of the satellites, the hypothesized deformation plane and the accuracy of InSAR measurements. The proposed procedure has been applied to the illustrative case study of the Albiano-Magra Bridge in Italy, collapsed on 8 April 2020. The results, referred to the monitoring period 2015–2020, demonstrate the effectiveness of the proposed method in supporting engineering assessments. In particular, an initially temperature-induced stationary deformation phenomenon has been observed, with all spans moving upwards or downwards during summer and winter. Afterwards, displacements of increasing amplitude for two side spans have been observed during the three years preceding the failure, providing information on the possible cause of collapse.
A Call for Health Education Specialists: Addressing Racism Through an Ecological Framework
Authors: Pettit Michele L. , Pember Sarah E.
Published: May 2022

In the wake of the COVID-19 pandemic, racism has emerged as a priority area for the public health community. Due to systemic racism, persons of color have faced decades of inequities in education, health care, employment, transportation, housing, and other realms. These inequities have resulted in numerous disparities in health status and most recently have manifested in the disproportionate number of deaths from COVID-19 and inadequate access to COVID-19 vaccines among persons of color. We highlight historical and contemporary public health implications of racism and present strategies health education specialists can employ to address racism at each level of the ecological model.
A Socially Distanced Case Study: Implementing the Unified Protocol-Adolescent in the Treatment of Comorbid Depression and Anxiety via Telehealth
Authors: Martin McKenzie R. , Bolden Jennifer , Walton Jaima
Published: May 2022

Anxiety and depression are two of the most common mental health diagnoses in adolescents, with higher prevalence rates for gender-nonconforming youth relative to an age-equivalent population of cisgender youth ( Veale et al., 2017 ). This case study examined the effectiveness of the Unified Protocol-Adolescent (UP-A) for a gender-nonconforming 13-year-old diagnosed with both generalized anxiety and mild depression. Amid the ongoing COVID-19 pandemic, this transdiagnostic implementation provided psychoeducation and targeted emotion identification, present-moment awareness, cognitive restructuring, and problem-solving over 21 sessions. Outcome data demonstrated significant reductions in anxiety and depression symptoms, with a notable qualitative change on three subjective measures of anxiety/depression symptoms, as ratings moved from clinical to nonclinical score ranges. Moreover, outcome data demonstrated the potential efficacy of the UP-A administered via telehealth for nonbinary youth with comorbid anxiety and depression. Clinical and research implications regarding the utility of implementing a flexible, transdiagnostic approach to treating diverse adolescents’ emotional disorders are discussed.