bluuebunny/crossref_metadata_2025 huggingface dataset:
Investigation on multiple periodic solution branches of a system with piecewise linear nonlinear energy sink
Authors: Wang Qian , Liu Heng , Liu Yi , Yu Yupeng , Jing Minqing
Published: January 2022

The multiple solution problem of nonlinear energy sinks (NESs) is of great interest in academic research and engineering applications; however, there exists only limited work on the multiple solution branches of piecewise linear NESs. Piecewise linear NESs can give rise to the appearance of isolated solution branches (ISBs), which are harmful to the performance of dynamical systems. It is difficult to detect the ISBs of a dynamical system with a piecewise linear NES. Hence, in this study, the multiple periodic solution branch distribution of a four-degree-of-freedom dynamical system with a piecewise linear NES is investigated. A method based on polynomial homotopy that can capture ISBs is developed to search multiple solution branches. Spurious periodic solutions can exist owing to the use of the implicit polynomial approach; therefore, the harmonic balance method with high harmonic orders and alternating frequency/time-domain technique are employed to distinguish true periodic solutions. Numerical experiments demonstrate that the proposed method can search for multiple periodic solution branches. A parameter analysis is conducted on the multiple solution branches, and the inner and outer ISBs are observed.
Optimization and experimental study on structural parameters of bio-inspired tarsus compliant end-effector to reduce the risk of fruit sliding out from end-effector for cherry tomato harvesting
Authors: Xie Huaibei , Kong Deyi , Wang Qiong
Published: January 2022

High success rate of fruit picking is part of key technologies for robotic cherry tomato harvesting, which is closely related to the structure of end-effector. In order to prevent the fruit slipping from the end-effector for a high success rate of fruit picking during picking process, this paper presents a compliant end-effector with bio-inspired tarsus compliant gripper inspired by the structure and mechanics of the tarsal chain in the Serica orientalis Motschulsky. An experimental study to confirm the effect of the key structural parameters of the compliant end-effector on the angle (ESGA) formed by the extended segment tarsomere of two bio-inspired tarsus compliant grippers. Experiments were designed according to response surface methodology—box Behnken design by maintaining three levels of four process parameters—length of the offset segment tarsomere (OSL), angle of the inclined segment tarsomere (ISA), thickness of the extended segment tarsomere (EST), and length of the extended segment tarsomere (ESL). Results showed that ISA is the most important parameter, and ESL has little effect on ESGA, and ESGA was found within the range of 4.2°–17.5°. Results also revealed that the desired ESGA (12°) was obtained by the optimum conditions of OSL of 2.4 mm, ISA of 18°, EST of 4.9 mm, and ESL of 18 mm. Besides, the key structural parameters of the bio-inspired tarsus compliant end-effector are optimized by the expectation function. The reliability and feasibility of the constructed model are verified by validation experiments.
Influence of the inlet boundary layer on non-axisymmetric endwall contouring effects in a linear compressor cascade
Authors: Ma Yuchen , Teng Jinfang , Zhu Mingmin , Qiang Xiaoqing
Published: January 2022

The modern aero-engine compressors are commonly designed to be highly loaded which can introduce strong three-dimensional flow separation, and effective flow control is of vital importance in improving compressor performance. Non-axisymmetric endwall contouring nowadays is conducted on axial compressors to control the flow separation. In this paper, a contoured endwall is designed based on a linear CDA compressor cascade. The genetic algorithm and ANN surrogate model are used in the optimization process of the hub contouring, based on RANS simulations. Three inlet boundary layers which follow the fully turbulent boundary layer assumption are generated with different thickness, and the influence mechanism is numerically investigated. The optimal endwall with streamwise concave near the suction side provides great performance improvement at all inlet boundary layers at the aerodynamic design point. The endwall flow near the suction side is accelerated by the contoured endwall with cross-flow pressure gradient altered, suppressing the corner separation. The main pressure loss is closely related to one streamwise vortex that blocks the endwall flow. A thicker inlet boundary layer can induce early forming and increased strength on the streamwise vortex, enhancing the cross-flow movement and its interaction with the blade surface flow. In addition, the pressure loss near endwall in the inlet boundary layer is found more dominant on the endwall contouring effect than the boundary layer thickness.
Size-dependent vibrational behavior of embedded spinning tubes under gravitational load in hygro-thermo-magnetic fields
Authors: Lingling Liu , Ruonan Ma , Koochakianfard Omid
Published: January 2022

In the present investigation, with the aim of performance improvement of size-dependent bi-gyroscopic structures, the vibrational behavior of spinning small-scale tunes conveying fluid embedded in various foundations subjected to distributed tangential load and hygro-thermo-magnetic environments by including gravitational effect is investigated. The modified couple stress theory is used to study the microscale tube, and the modified nonlocal theory is utilized to model the nanoscale tubes. A parametric investigation is also conducted to highlight the impacts of various key factors such as gravity, flow profile modification factor, fluid velocity, spinning speed, substrate coefficients, boundary conditions, size-dependent parameters, and environmental attacks on divergence and flutter thresholds of the structure. The dynamical equations are solved using Laplace transformation as well as Galerkin discretization techniques, and forward and backward frequencies are identified accordingly. Meanwhile, the instability borders of the system are obtained analytically. Campbell and stability diagrams, and the time history of the system, are acquired. The results revealed that contrary to influences of gravity, magnetization, and size-dependent parameters, the compressive tangential load and humidity have decreasing effects on the vibrational frequencies and make the system prone to experience static and dynamical instabilities. Moreover, it is determined that applying the viscous foundation eliminates the re-stabilization zone in the system stability evolution, and after the occurrence of the divergence phenomenon, the system immediately undergoes the flutter instability.
Analytical study of creeping flow of Maxwell fluid in a permeable slit with linear re-absorption
Authors: Mehboob Hira , Maqbool Khadija , Ramzan Muhammad , Jamil Qudsia , Malik Muhammad Yousaf
Published: January 2022

This research presents the analytical study of the creeping flow of a Maxwell fluid in a permeable slit under the effect of linear reabsorption. Analysis of fluid leakage on the slit wall is carried out with the help of the law of conservation of momentum in the rectangular coordinates. The mathematical model in the form of the system of nonlinear partial differential equations is solved by the recursive approach explaining the hydrodynamic aspects of creeping Maxwell fluid flow. The expressions for the velocity field, hydrostatic pressure, stream function, leakage flux, and fractional reabsorption on the boundary of the slit are obtained from the mathematical model. Graphical analysis is also established to demonstrate the effects of emerging parameters due to linear reabsorption on slit boundary and relaxation time. It is analyzed that the horizontal and vertical velocity decelerates by the growing values of the relaxation parameter, but the reabsorption rate gives an increasing effect on the shear stress, volume flow rate, and vertical velocity. This analytical study will help the bioengineers in designing the medical tools with the required pressure and flow rate, therefore the application of this model for the hemodialyzer is also important.
An experimental investigation of the potential of empirical correlations derived based on Dalton’s law and similarity theory to predict evaporation rate from still water surface
Authors: Aldarabseh Safa M , Merati Parviz
Published: January 2022

This paper investigates the applicability of two approaches (similarity theory and Dalton’s law) in predicting the evaporation rate. The results of this study showed that conventional Dalton’s based models could not be used to predict the evaporation rate at all convection regimes. Thus, a new formula as a function of vapor density difference was developed to predict evaporation rate at natural turbulent convection. However, still, it cannot get an acceptable result. Also, another two formulas were developed to predict the evaporation rate at forced and mixed convection regimes after considering the nonlinear relationship between the evaporation rate and the vapor pressure difference. The evaporation rate is proportional to the exponent ( n) of the partial vapor pressure difference. This exponent was written as a function of the higher-order polynomial of air velocity to get a good match between experimental results and predicted value, and satisfactory results were achieved. Similarity theory is an analogy between heat and mass transfer methods used to predict the evaporation rate from the still free water surface. The results show that the evaporation rate obtained from the similarity method is much larger than the actual evaporation rate. The similarity theory considers the effect of the vapor density difference. Thus, it can be observed that the experimental results and similarity method results are in good agreement at natural turbulent convection. It is noteworthy that the similarity theory cannot predict the evaporation rate from the still water surface at forced convection. In this convection regime, the evaporated water surface is not completely smooth, which violates the assumption of the similarity theory. A nonlinear regression analysis was conducted to evaluate the empirical correlation of the Sherwood number for mixed convection under turbulent conditions with the exponent n as a logarithmic function of the ratio [Formula: see text], then derived a new formula that can be used to evaluate evaporation rate at mixed convection regime, and the results are in good agreement with the experimental results. The laboratory measurements are made using the large wave tank-wind tunnel combination to control wind speed.
A Flow Model for Side Chambers of Centrifugal Pumps Considering Radial Wall Shear Stress
Authors: Gu Yandong , Cheng Jinwu , Wang Peng , Cheng Li , Si Qiaorui , Wang Chuan , Shouqi Yuan
Published: January 2022

The side chamber flow has a fundamental influence on the performance and reliability of centrifugal pumps. However, the radial wall shear stress in the flow modeling of pump side chambers is arbitrarily neglected. The current work proposes a model for the radial wall shear stress, which is an extension of the previous paper (DOI: 10.1115/1.4047532). By using the power-law for the velocity boundary layer and the Blasius law for the wall shear stress, introducing the Ekman layer thickness expression, and deducing the Bödewadt layer thickness expression, the radial wall shear stress on the rotating and stationary disks is formulated and then integrated into the side chamber flow model. Besides, the entire flow field of the centrifugal pump is solved using the computational fluid dynamics (CFD) software ANSYS CFX. The radial wall shear stress calculated by the new side chamber flow model (NSCFM) is in the identical magnitude as CFD. Compared with pressure measurements, NSCFM makes better pressure predictions than CFD from the rear seal to the hub; however, in other areas, CFD results are closer to experimental data than NSCFM results. The flow prediction tools show that the volumetric efficiency and the shroud thrust increase with the increase in flow rate. NSCFM achieves a good compromise between calculation speed and desired accuracy.
Force impact suppression of contact transition state in robot grinding and polishing of industrial blades
Authors: Li Zhen , Wang Hui , Zhao Huan , Ding Han
Published: January 2022

When using robots to carry out grinding and polishing processing of industrial blades, due to factors such as non-zero approach speed and discontinuous dynamic characteristics, the robot grinding and polishing processing has contact force impact and oscillation problems during the contact transition process, which seriously affects the quality of the blade surface processing, contour accuracy, and control system stability. In order to solve the problem of large impact of contact force in robot grinding and polishing, this paper proposes an optimization method for impact suppression in the transition state of robot grinding and polishing. Taking the robot abrasive belt grinding and polishing as the research object, the adaptive weighted particle swarm algorithm is used to optimize the input shaper and realize the parameter self-tuning of the input shaping technology. The experimental results show that the stabilization time is shortened by about 86.5%, and the maximum overshoot of contact force is reduced by about 88.5% during contact transition. The method proposed in this paper can realize the smooth transition of the blade grinding and polishing process, does not need system modeling, effectively shorten the system stabilization time, reduce the maximum overshoot, and accelerate the system response speed, and it has strong stability and flexibility.
Design and contact characteristics analysis of a new internal twin-screw pump
Authors: Zhewei Ye , Liang Luo , Kang Feng , Qinjue Yi , Lang Tan
Published: January 2022

This paper designs a new internal meshing twin-screw pump (new twin-screw pump). To study the new twin-screw pump in the principle, performance parameters, and contact characteristics of the differences with the single-screw pump, the mathematical method of motion conversion is used to convert the planetary motion of the single-screw pump into the fixed-axis rotation of the internally intermeshing twin-screw pump. It is found that the movement relationship of the two pumps is similar. When the structural parameters of the two pumps are the same, the flow per revolution of the single-screw pump is N+1 times that of the new twin-screw pump. To obtain the force transmission characteristics in the internal meshing process, a numerical method was used to analyze the structure of the new twin-screw pump statically. Due to the existence of the meshing relationship, the influence of the screw meshing fit clearance, progression, and pitch on the contact stress is further explored. The results of the study show that the internal and external rotor contact stresses show a trend of small in the middle and large at the ends, the stress distribution coefficient [Formula: see text] increases with the increase of the mating clearance, and the stress distribution becomes uneven with the increase of the number of screw stages and pitch. The results of this study provide a basis for the reasonable selection of structural parameters of the new twin-screw pump.
Analysis of the incremental sheet forming process and process parameters on aluminum sheets based on the vertical step sizes
Authors: Malyer Elif , Sönmez Fikret
Published: January 2022

The incremental sheet forming (ISF) is an effective forming method developed especially for rapid prototyping and small-batch production of sheet metals. The selection of parameters (in particular, vertical step size and toolpath geometry) in ISF is crucial. Besides, each parameter has different effects on the desired geometry, sheet thickness, forming time, and productivity. In this study, the ISF process was analyzed by investigating the effects of ISF parameters. For this purpose, AA5754 sheets were formed by different ISF parameters. The effects of toolpath strategies (based on the vertical step size) were examined with three spindle speeds and three feed rates. To achieve that objective, constant, increasing, and decreasing vertical step sizes were used for the first time in the same study. After the forming, the forming time, geometric tolerance, and thickness values were analyzed. Besides, the efficiency of each parameter on the ISF process was investigated with the Pareto analysis. It has been revealed that each strategy has some advantages and disadvantages in ISF. The shortest forming time (1.55 min), the best geometric tolerance values (−0.05 mm, +0.2 mm), and the best thickness values (0.58 mm, 0.51 mm) were achieved following toolpath strategy 1, strategy 2, and strategy 3, respectively. The Pareto analysis showed that spindle speed and feed rate have a significant effect on toolpath strategies. The results obtained from this study will shed light on the effective advancement of small-batch production of sheets. Furthermore, the study contributes to the determination of parameters according to which of the sheet metal properties are desired.
Study on mechanical and tribological characteristics of layered functionally graded polymer composite materials
Authors: Boggarapu Vasavi , Ruthik L , Gara Dheeraj Kumar , Ojha Shakuntala , Jain Satish , Gujjala Raghavendra , Bandaru Aswani Kumar , Inala Ramu
Published: January 2022

It is apparent that well-designed functionally graded materials (FGMs) exhibit smooth transition in properties. In this paper, polymer based functionally graded composite materials (FGCMs) were developed in combination with copper (Cu) particles and epoxy. A novel stepped layer configuration through a curing-phase approach at each layer in three different curing conditions (C1, C2, C3) have been processed. A significant enhancement in mechanical strength and erosion resistance was observed at higher curing temperatures (60°C) for sample C3. The results indicated tensile and compressive strengths of C3 enhanced by 40.20%, 17.48% and 20.18%, 9.74% compared to C1 and C2, respectively. Furthermore, when the FGM is loaded from top to bottom (T-B), there is an enhancement in flexural strength of C3 by 7.88% when compared to bottom to top (B-T) loading. In addition, the erosion wear of C3 was found to be lowest of all the samples.
Partnership status and time to viral suppression and sustained viral suppression among newly diagnosed heterosexual people with HIV
Authors: Sohail Maira , Long Dustin M , Batey D Scott , Mugavero Michael J , Ojesina Akinyemi I , Levitan Emily B
Published: January 2022

Background

Previous studies examining the role of partnership on HIV care outcomes have primarily focused on the men who have sex with men population in the United States, leaving a gap in the literature on this phenomenon among the heterosexual persons with HIV (PWH). This study examined association between partnership around diagnosis (married, unmarried-partnered, and un-partnered) with time to viral suppression (TVS) and sustained viral suppression (SVS) in newly diagnosed heterosexual PWH from a HIV clinic in Birmingham, Alabama.

Methods

TVS [time to first viral load (VL) <200 copies/ml] was measured using VLs from 12 months following diagnosis using Kaplan–Meier and proportional hazard model for interval censoring ( n=153) to calculate hazard ratios (HRs) and 95% confidence intervals (CIs). SVS was measured using VLs for 12 months after first VS using logistic regression model ( n=137) to calculate odds ratios (ORs) and 95% CIs. Models were adjusted for confounding demographics and clinical characteristics.

Results

The study population comprised of 77% Black, 57% male, and 46% aged 31–49 years; 24% were married, 35% unmarried-partnered, and 41% un-partnered. The median TVS (days) was 57 for married, 73 for unmarried-partnered, and 75 for un-partnered. Compared to un-partnered individuals, unmarried-partnered had similar, whereas married had 69% higher [HR (95% CI): 1.69 (1.02, 2.78)] hazard of TVS. Compared to un-partnered, unmarried-partnered and married individuals had similar odds of achieving SVS.

Conclusion

Married, newly diagnosed, heterosexual PWH had faster TVS than un-partnered individuals suggesting that intimate partners may help achieve HIV care goals.
Investigations into heat transfer and film cooling effect on winglet-squealer tips in a turbine stage
Authors: Yan Xin , Ye Mingliang , Huang Yan , He Kun
Published: January 2022

Heat transfer and film cooling effect on three kinds of winglet-squealer tips (i.e., conventional squealer tip, no P.S. rim tip and P.S. winglet tip) in a turbine stage are numerically investigated at two operation conditions (i.e., laboratory testing condition and sea-level take-off condition) and three cooling hole arrangements (i.e., un-cooled, with tip holes, and with both tip and pressure side holes), and the numerical results are also compared with those in stationary cascades. To reduce the heat transfer while enhancing film cooling effect on the P.S. winglet tip, ejection angles for the tip and pressure side cooling holes are varied to reveal the superior performance of P.S. winglet tip in turbine stage. The results show that the heat transfer coefficient and film cooling effectiveness distributions on three kinds of tips exhibit different trends in the stationary and rotating cases. Tip rotating significantly affects the trajectories of cooling flow in the conventional squealer tip and no P.S. rim tip due to different vortex system induced in the cavity. However, the relative rotating has little influence on the flow structures in the P.S. winglet tip. In un-cooled condition, the area-averaged heat transfer coefficient on P.S. winglet tip is lower than the conventional squealer tip by 11.6%. For the vertical ejection case in turbine stage, the P.S. winglet tip has a slightly worse heat transfer and film cooling effect than the conventional squealer tip. However, with inclined ejections, the area-averaged heat transfer coefficient on winglet tip in turbine stage is lower than the conventional squealer tip by 15.3%, and the area-averaged film cooling effectiveness on winglet tip is higher than the conventional squealer tip by 12.1%.
Numerical investigation of heat exchanger pipe equipped with chamfered circular ring separated from wall to intensify thermo-hydraulic performance
Authors: Agham Rahul D , Mahalle Ashish M
Published: January 2022

Chamfered circular ring (CCR) innovated from conventional circular ring by introducing chamfered surface on its periphery at 30o attack angle is numerically investigated to study its effect on fluid flow characteristics, heat transfer enhancement, and friction factor in a heat exchanger pipe. In order to study flow blockage effect on overall performance of device, three diameter ratios (DR = Di/Do = 0.6, 0.7 and 0.8) with three spacing ratios (SR = s/D = 1, 2 and 3) are used. Turbulent model k – ε, RNG with enhanced wall treatment is used to solve governing equations. Results showed that CCR chamfered surface produced nozzle jet effect on pipe wall surface through clearance of 1 mm, which further induced turbulent and recirculating flow effect near pipe wall area. This resulted into higher heat transfer rate. All the diameter ratios with SR = 1 showed thermal performance factor value more than unity at most of the lower Reynolds number. The range of TPF shown by DR = 0.6, 0.7 and 0.8 with SR =1 is 1.21–0.93, 1.23–0.97, and 1.19–0.99, respectively. Compromised results of TPF are shown by DR = 0.7 and DR = 0.8 at SR = 1. Chamfered circular ring has shown better results over circular ring, perforated conical ring, short length twisted tape, twin co-twisted tape, wire rod bundles, and perforated twisted tape. Numerical results showed better agreement with predicted results within the range of 10%. Highest TPF of 1.23 is shown by DR = 0.7 and SR = 1 at Re 6000.
Mathematical model of hydraulic ram pump system
Authors: Li Jiazhen , Yang Kailin , Guo Xinlei , Huang Wei , Shi Chunrong , Guo Yongxin , Wang Tao , Fu Hui , Pan Jiajia
Published: January 2022

The hydraulic ram pump is water-powered machinery using low-head hydroenergy. An overall mathematical model is presented to consider the dynamic behavior of the waste and delivery valves. Model experiments, numerical simulations, and references analysis are combined to investigate the characteristics of pressure and water level fluctuations, the motion of the waste and delivery valves, as well as corresponding performance optimizations. The mathematical model can well represent the pressure and water level characteristics of the hydraulic ram pump, as well as the motion of the waste and delivery valves. The numerical results are in good agreement with the measured peak value, trough value, waveform, and period. The opening and closing of the waste valve are found to meet the power-function of time with the power exponents 1.5 and 0.2, respectively, while the delivery valve can experience multiple opening-closing processes for low lift cases. The partial water volume in the air chamber flows back into the pump body during the closure of the delivery valve, resulting in the degradation of the delivery flow. The delivery valve of perforated structure is a priority for the high lift case due to reducing backflow, while that of lift-check-valve structure is advised for other cases because of the small local head loss coefficient.
The labour market impact of robotisation in Europe
Authors: Antón José-Ignacio , Klenert David , Fernández-Macías Enrique , Urzì Brancati Maria Cesira , Alaveras Georgios
Published: January 2022

This paper explores the impact of robot adoption on European regional labour markets between 1995 and 2015. Specifically, we look at the effect of the usage of industrial robots on jobs and employment structures across European regions. Our estimates suggest that the effect of robots on employment tends to be mostly small and negative during the period 1995–2005 and positive during the period 2005–2015 for the majority of model specifications. Regarding the effects on employment structures, we find some evidence of a mildly polarising effect in the first period, but this finding depends to some extent on the model specifications. In sum, this paper shows that the impact of robots on European labour markets in the last couple of decades has been ambiguous and is not robust. The strength and even the sign of this effect are sensitive to the specifications, as well as to the countries and periods analysed.
When accumulation pressures meet regulatory institutions: A comparison in logistics
Authors: Pulignano Valeria , Thompson Paul , Doerflinger Nadja
Published: January 2022

This comparative study explores whether and how institutions can become a source of influence on accumulation dynamics in the labor process. It examines how employer strategies for the realization of value within the warehousing, parcel, and transport business divisions of a lead logistics multinational are operationalized in Germany, Belgium, and Sweden. Findings indicate within (and across) country variation in the operationalization paths we identify: compliance, avoidance, and exit. We explain the cross-country variation of each path by pointing to the strategies and negotiation processes pertaining to the usage of flexible labor at each workplace. We also illustrate that this usage relates to the mechanisms of optimization by standardization and of relational management used by employers to contain costs within the scope of each division’s managerial regime.
Slow, slow, quick, quick, slow: The ‘thick and thin’ of comparative (statactivist) research with a European trade union federation
Authors: Turnbull Peter
Published: January 2022

The greater insight and deeper understanding generated by slow comparative international research is beyond doubt. However, there are times when researchers need to ‘quicken up’, most notably when engaged in ‘real-time’ social science that is directly responsive to policy initiatives by the (supranational) state and/or new business strategies and employment practices developed by (multi-national) employers. This is a particular challenge for scholars working with European trade union federations, especially when they are drawn into political campaigns and/or European policy debates. Such engagement often calls for a (quick) step from slow (typically qualitative) to fast (predominantly quantitative) research, using statistics for activism in order to build evidence for representation that can pass the test of science as well as the test of action. The evidence is necessarily ‘thin’ but nonetheless sufficient, on occasion, to warrant collective action.
Nurses’ experiences of ethical responsibilities of care during the COVID-19 pandemic
Authors: Peter Elizabeth , Mohammed Shan , Killackey Tieghan , MacIver Jane , Variath Caroline
Published: January 2022

Background

The COVID-19 pandemic has forced rapid and widespread change to standards of patient care and nursing practice, inevitably leading to unprecedented shifts in the moral conditions of nursing work. Less is known about how these challenges have affected nurses’ capacity to meet their ethical responsibilities and what has helped to sustain their efforts to continue to care.

Research objectives

1) To explore nurses’ experiences of striving to fulfill their ethical responsibilities of care during the COVID-19 pandemic and 2) to explore what has fostered nurses’ capacity to fulfill these responsibilities.

Research Design

A generic qualitative approach was used incorporating concepts coming from fundamental features of care.

Participants

Twenty-four Canadian Registered Nurses from a variety of practice settings were interviewed.

Ethical Considerations

After receiving ethics approval, signed informed consent was obtained before participants were interviewed.

Findings

Four themes were identified. 1) Challenges providing good care in response to sudden changes in practice. 2) Tensions in juggling the responsibility to prevent COVID-19 infections with other competing moral responsibilities. 3) Supports to foster nurses’ capacity to meet their caring responsibilities. 4) The preservation of nurses’ moral identity through expressions of gratitude and health improvement.

Discussion

Infection control measures and priorities set in response to the pandemic made at distant population and organizational levels impacted nurses who continued to try to meet the ideals of care in close proximity to patients and their families. Despite the challenges that nurses encountered, the care they received themselves enabled them to continue to care for others. Nurses benefited most from the moral communities they had with their colleagues and occasionally nurse leaders, especially when they were supported in a face-to-face manner. Conclusion: Moral community can only be sustained if nurses are afforded the working conditions that make it possible for them to support each other.
The Anthropocene Judgments project: A thought experiment in futureproofing the common law
Authors: Rogers Nicole , Maloney Michelle
Published: January 2022

We introduce here a new critical judgments project: the Anthropocene Judgments project. The project is intended to be an interdisciplinary, collaborative, visionary initiative, a collective effort on the part of legal scholars, writers of speculative fiction, literary scholars and climate scientists to anticipate what may lie ahead. Participants will engage in futuristic modelling and write judgments of, and for, the future – constructing innovative pathways of legal reasoning to address the novel, socio-legal and environmental challenges of the Anthropocene. In this article, we develop our ideas for the project, canvass possible directions for future judgment writing and explain the importance of this ambitious endeavour.
Applying the Psychology of Working Theory for Understanding Adaptive Career Progress of Youth
Authors: Kenny Maureen E. , Haase Richard F. , Tsai Brenda W. , Medvide Mary Beth. , Davila Alekzander
Published: January 2022

This study extends existing research on psychology of working theory by assessing components of the model among two community samples ( N = 364) of high school youth. We examined structural models linking student perceptions of external barriers to higher education to three indices of adaptive career progress, work volition, career adaptability, and school motivation. We also assessed the roles of student perceptions of proactive personality, critical motivation, and teacher social support as moderators of perceived external barriers for the three career progress indices. The findings reveal main effects, rather than moderating contributions for critical motivation and proactive personality, with only teacher support being a significant moderator for career adaptability and work volition. The moderating effect was inconsistent with theoretical expectations, however. The results are discussed with attention to further research and applicability for vocational intervention.
Young Adults’ Self-Regulatory Responses to Positive Career Goal Discrepancies: Testing Cross-Lagged Relationships
Authors: Akmal Sari Z. , Hood Michelle , Creed Peter A. , Duffy Amanda L.
Published: January 2022

Researchers have assessed young people’s outcomes when they do not meet their career goals, but little is known about the consequences when they do better than expected (positive discrepancies). We (a) tested the cross-lagged relationships between positive career goal discrepancies and the career-related outcomes of upward goal revision, career exploration, and career coasting, and (b) assessed the indirect relationships between positive career goal discrepancy and outcomes through self-efficacy and outcome expectations. Using a sample of 314 young adults (76% female, Mage 19.13 years), we found that the standard causation model was the most parsimonious. Positive discrepancies predicted more upward goal revision and exploration and less coasting after a 6-month time lag, both directly and indirectly through outcome expectations. The findings highlight the importance of positive career goal appraisals in career goal-setting, exploration, management and clarify the roles of agency (self-efficacy and outcome expectations) as explanatory mechanisms in these relationships.
How to Build Declarative and Procedural Fluency Simultaneously Using Complementary Independent Practice Strategies
Authors: Morano Stephanie , Aigotti Susan
Published: January 2022

Fluency in math facts and procedures is critical for math achievement overall and often challenging for students with emotional and behavioral disorders to develop. This article describes how to implement two complementary and evidence-based practice strategies, incremental rehearsal and Cover-Copy-Compare, to build declarative and procedural fluency in tandem. How-to steps, example materials, and additional resources are provided.
Theoretical optimization and experimental verification of a non-contact damper for high temperature superconducting Maglev systems
Authors: Li Haitao , Deng Zigang , Huang Huan , Yu Jinbo , Wang Li , Zhang Weihua
Published: January 2022

High-temperature superconducting (HTS) maglev has excellent potential in high-speed transportation due to its capability of passive stabilization levitation. However, in applications, the vibration of maglev vehicle with a large amplitude will be triggered for some external incentives or interference owing to its weak damping characteristics. Hence, it is preferable and necessary to find a way to reduce the vibration without mechanical contact. In terms of mechanical structure, the HTS maglev system mainly consists of HTS bulks and permanent magnets guideway (PMG). Utilizing the magnetic field provided by PMG, we designed and assessed an electromagnetic shunt damper (EMSD) for the HTS maglev system, by which the vibrations can be attenuated without contact. At first, the parameters of EMSD were theoretically optimized, respectively. Second, according to the structure of the Halbach PMG, the experimental EMSD was presented. In this damper, two groups of coils in reverse series were set above the two magnetic poles of the PMG to get a large induced electromotive force. Eventually, the experimental results show that the vibrations of the HTS maglev model vehicle can be attenuated more than 80% in the resonance region when the designed EMSD was employed in the system. Namely, this non-contacting damper will highly enhance the dynamic characteristics of HTS maglev systems.
Recurrence of Substantiated Maltreatment Reports between Low-Income Parents With Disabilities and Their Propensity-Score Matched Sample Without Disabilities
Authors: Cho Minhae , Lightfoot Elizabeth
Published: January 2022

Using the Longitudinal Studies of Child Abuse and Neglect dataset, 127 low-income parents with disabilities and a propensity score matched sample of 254 parents without disabilities were compared for the rates of repeated substantiated child maltreatment allegations and potentially distinct risks for substantiated child maltreatment recurrence. The number of substantiated child maltreatment allegations was not significantly higher for low-income parents with disabilities (M = 1.17, SD = 1.83) than their matched sample (M = .93, SD = 1.44) ( t = −1.29, p = .197). Findings from the negative binomial regression indicated that parental disability was also not a significant predictor for repeated substantiated child maltreatment allegations among low-income parents after controlling other risk factors (Exp(B) = 1.16, p < .353). In both groups, black parents were more likely to have repeated substantiated maltreatments than white parents. For parents with disabilities, being an older parent, receiving SNAP benefits, having a daughter, and having a child in continued out-of-home care significantly increased the risk for repeated substantiations while having a GED or higher education degree and living with a larger number of family decreased the risk. For parents without disabilities, family instability was the only additional risk factor for repeated maltreatment substantiations.
Risk of Postneonatal Infant Mortality Associated With Prior Founded Allegations of Child Abuse
Authors: Hauck Fern R. , Tanabe Kawai O. , Blackstone Sarah R.
Published: January 2022

This study examined the association between prior reports of child abuse and subsequent postneonatal death and differences by cause of death, using data from the Chicago Infant Mortality Study (CIMS). CIMS included all sudden, unexplained infant deaths up to 1 year of age in Chicago (November 1993–April 1996), and age, race-ethnicity, and birthweight-matched living controls. Information on prior child abuse reports and outcomes was obtained through the Illinois Department of Children and Family Services (DCFS) State Central Registry for each case and control. Conditional logistic regression modeling determined the odds of postneonatal death when there was a founded prior allegation. Families with founded allegations were almost 4 times more likely to have a child die during the postneonatal period (aOR = 3.79, 95% CI, 1.56, 9.10). Child protective services involvement is an opportunity for education on safe sleep messaging to help reduce the incidence of potentially preventable infant deaths.
Inequities in Child Protective Services Contact Between Black and White Children
Authors: Thomas Margaret M. C. , Waldfogel Jane , Williams Ovita F.
Published: January 2022

Child protective services (CPS) contact occurs at substantially higher rates among Black than White families. The present study considers systemic racism as a central driver of this disparity and emphasizes racialized poverty as a possible mechanism. We used data from the Fragile Families and Child Wellbeing Study and logistic regression analyses to assess the associations between income poverty, a racialized experience, and CPS contact, separately among Black and White families. Results indicated that income poverty was a significant predictor of CPS contact among White families, who were protected by higher income. In contrast, income per se was not a significant predictor of CPS contact among Black families, who were instead impacted by racialized family regulation and consequences of poverty, such as poor health and depression. Refundable state Earned Income Tax Credit (EITC) policies were protective for Black families, and more expansive Temporary Assistance for Needy Families (TANF) programs decreased CPS contact for Black and White families. Implications include centering systemic racism and specifically racialized poverty as causes of racial inequities in CPS contact and rethinking the role of CPS in protecting children.
The Development of Young Peoples’ Internalising and Externalising Difficulties Over the First Three-Years in the Public Care System
Authors: Hiller Rachel M , Fraser Abigail , Denne Megan , Bauer Andreas , Halligan Sarah L
Published: January 2022

Although we know there are high rates of mental health difficulties amongst young people in out-of-home care (i.e. social welfare-involved children), there is limited evidence on the longitudinal development of these problems, particularly from when they enter the care system. Using the routinely collected carer-reported strengths and difficulties questionnaire, we explored internalising (emotional and peer) and externalising (conduct and hyperactivity) difficulties for 672 young people across their first 3 years in the UK care system (2–16 yrs, 51% boys, 76% Caucasian). In all cases stable profiles (resilient or chronic) were most common, while changing profiles (recovery or delayed) were less common. Findings showed that entry into the care system is not enough of an intervention to expect natural recovery from mental health difficulties. Number of placements and being separated from siblings were associated with greater difficulties. Implications for child welfare and mental health systems are discussed.
What Difference Does Time Make? Analysis of Driver Behaviors Before and After Toll Implementation
Authors: Yusuf Juita-Elena (Wie) , Chapman David , O’Connell Lenahan , Jordan Meagan M. , Anuar Khairul A.
Published: January 2022

This study examines if and how drivers respond to tolls differently after implementation by analyzing drivers’ intention to pay tolls and toll avoidance behaviors. We apply the Theory of Planned Behavior to connect intention to pay and avoidance behavior to three categories of predictors: attitudes toward tolls, perceptions of toll benefits, and ability to pay. Since the theory does not explicitly consider factors such as past experience and changes in the decision-making process over time, we utilize three analytical approaches to examine: (1) if time affects intention to pay tolls and toll avoidance behavior; (2) pathways through which time makes a difference, and (3) how factors influencing intention behaviors change pre- and post-toll implementation. We find that time does in fact matter; there are direct and indirect pathways through which time makes a difference and time changes the strength of the relationships between intention to pay and behavior.
Perceived Message Effectiveness: Do People Need to Think About Message Effectiveness to Report the Message as Effective?
Authors: Popova Lucy , Li Yachao
Published: January 2022

How people make perceived message effectiveness (PME) judgments remains mostly unexplored. This study assessed whether people need to spontaneously think about message effectiveness to report the message as effective on rating scales and investigated emotions as precursors to PME. After viewing one of four e-cigarette prevention messages, 1,968 adult current and former smokers and nonsmokers freely expressed thoughts about the messages in an open-ended question and answered close-ended PME items. Four expressed PME variables (positive message perceptions, negative message perceptions, positive effect perceptions, and negative effect perceptions) were coded (1 = present, 0 = absent) in the open-ended responses, and all were significantly associated with measured PME. Positive and negative emotions predicted both expressed and measured PME. Negative message perceptions was the only expressed PME construct that mediated the relationships between emotions and measured PME and outcomes (perceived risk and behavioral intentions). This suggests that messages may not need to induce effectiveness thoughts to be reported as effective, but thoughts of message ineffectiveness are a useful indicator deserving further research.
A Team-Teaching Approach to Advertising Campaigns Capstone Course
Authors: Fernandes Juliana , Lu Lincoln , Nunez Sarai
Published: January 2022

Undergraduate advertising campaigns courses are known for their integration of knowledge, application of different skills, and group work. This capstone class partners with a real-world client and may be considered the last professional experience in an educational setting before students graduate. Using a multi-methods approach, this study describes a team-teaching method developed by advertising campaigns instructors at a mid-size private university in Florida, gauges students’ perceptions on several learning dimensions, and maps out how this course is taught in American universities.
Technique for a lateral approach to a superficial femoral artery-femoral vein thigh loop arteriovenous graft placement in avoidance of a traditional groin incision
Authors: Yuan Fang , De Grijs Derek , Goudreau Bernadette , Robinson William P
Published: January 2022

Introduction:

The number of patients with end stage renal disease reliant on long-term hemodialysis access continues to grow. When traditional upper extremity hemodialysis sites are exhausted, lower extremity access should be considered. Although autogenous lower extremity options are available, prosthetic lower extremity grafts are frequently used. However, infection can complicate a significant percentage of lower extremity grafts with a traditional groin incision. We present our technique and early results of a lateral approach to a superficial femoral artery-femoral vein thigh loop arteriovenous graft (lat-SFA-FV AVG) in the proximal thigh, which avoids a traditional groin incision and provides a functional access with promising patency.

Methods:

Between April 2017 and August 2019, five lat-SFA-FV AVG were placed in our institution for arteriovenous access in patients who had exhausted options in upper extremities.

Results:

Five patients were included in the study. Median SFA size was 8 mm. One patient had moderate SFA calcification, while the other four patients had either none or mild SFA calcification. All grafts were successfully placed with few postoperative complications, including no wound infections. One patient expired 3 weeks after the procedure due to unrelated cause. Three patients had functional grafts at a median follow-up of 499 days.

Conclusion:

Our early experience demonstrates that the lateral approach to the SFA-FV AVG has several advantages including avoidance of groin infection and acceptable patency. Furthermore, our early experience identifies patient factors which may be important to patient selection for this procedure.