bluuebunny/crossref_metadata_2025 huggingface dataset:
Tribological properties of rock-bit journal bearings tribo-pair with micro-dimples under contaminated grease lubrication
Authors: Zhong Lin , Kang Guirong , Wang Guorong , Wei Gang , Wang Zixuan , Wu Xiaolong , Chen Linyan
Published: December 2021

The failure of bit bearings is one of the main factors that restrict the life of a bit, and studies revealed that sealing and adhesive wear failure are common failure modes of bit bearings. To study the adaptability of the optimal textures to anti-wear and anti-friction performance of an 8 1/2” rock bit journal bearingunder sealing leakage conditions, the rheological properties of grease in the range of 0%–50% of the water-based drilling fluid volume in the compound lithium-based grease (rock bit grease) were tested. For the cylindrical dimples (diameter: 300 μm; depth: 40 μm, area ratio: 5%) and elliptical dimples (major and minor axis of 720 and 360 μm, respectively; depth: 40 μm, area ratio: 10%), the experimental study on the wear resistance of the optimized texture tribo-pairs was carried out as the grease invaded different drilling fluid contents based on the pin-disk pair. Results showed that the drilling fluid volume in the rock bit grease significantly affected the rheological properties of the grease. Furthermore, the cylindrical and elliptical dimples still had good anti-wear and anti-friction effects. Especially when the drilling fluid volume ratios in the grease reached 50%, the elliptical dimples can still reduce the friction coefficient and wear amount of the pair by 19.88% and 56.99%, respectively. With the increase of drilling fluid invasion into grease, the wear morphology of the un-textured tribo-pairs showed that the wear form changed from abrasive to adhesive wear, while that of the preferred textured tribo-pairs indicated slight abrasive wear.
Children’s oppositional defiant disorder symptoms make parents difficult to be nice: Longitudinal association among parent emotion regulation, child emotion regulation and children’s oppositional defiant disorder symptoms in Chinese children with oppositional defiant disorder
Authors: Chen Hui , He Ting , Xu Min , Zhao Jianjun , Li Longfeng , Lin Xiuyun
Published: December 2021

The current study aims to clarify the longitudinal relations among parent emotion regulation (ER), child ER, and children’s oppositional defiant disorder (ODD) symptoms. In the current study, parents of 275 children (195 boys, 70.1%) with ODD symptoms ( Mage = 9.32 years, SD = 1.64) reported their ER using the Difficulties in Emotion Regulation Scale, child ERs using the Emotion Regulation Checklist, and children’s ODD symptoms using the eight symptoms indicated in the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV-TR) at three time points (T1, T2, and T3) within 2 years. Results indicated the longitudinal relationships between parent ER and children’s ODD symptoms were directly influenced by each other. Children’s ODD symptoms had important effects on both child ER and parent ER. Findings suggested that to reduce children’s ODD symptoms, it is necessary not only to improve child ER but also to improve parent ER.
Implicit theories of body weight and engagement in healthy lifestyles among young adults: The mediating effect of self-control
Authors: Zhang Ying , Zhang Ning , Xu Chenyang
Published: December 2021

Engaging in a healthy lifestyle could be helpful to decrease lifestyle-related health risks and bring long-term health benefits. This research investigated how implicit theories of body weight influence people’s engagement in healthy lifestyle among young adults in China. The results suggested that implicit theories of body weight significantly influence people’s engagement in heathy eating behaviors and physical activity. Self-control mediated the effect of implicit (incremental) theories of body weight on people’s engagement in healthy eating. Implications of the current research for understanding how to promote engagement in healthy lifestyle and directions for future research are discussed.
The relationship between COVID-19-induced death thoughts and depression during a national lockdown
Authors: Fairlamb Samuel
Published: December 2021

Evidence suggests that the COVID-19 pandemic has increased rates of depression worldwide. Many factors have been identified to relate to this increase depression, but according to Terror Management Theory, the heightened awareness of death during the pandemic has the potential to increase depression for those with low self-esteem. This hypothesis was examined in a U.K. sample during the first national lockdown where depression, self-esteem and death-thought accessibility (DTA) were measured, and a COVID Index (COVID-19 cases and deaths on date of participation) was produced. The COVID Index was positively related to DTA. Additionally, DTA mediated the relationship between the COVID Index and depression scores when participants had low levels of self-esteem. These findings suggest that heightened existential concerns may be a neglected factor increasing depression during the pandemic.
Fatigue prediction model of ultra-high-performance concrete beams prestressed with CFRP tendons
Authors: Hu Rui , Fang Zhi , Jiang Ruinian , Xiang Yu , Liu Chuanle
Published: December 2021

In the present paper, a comprehensive study on the flexural fatigue behavior of ultra-high-performance concrete (UHPC) beams prestressed with carbon-fiber-reinforced polymer (CFRP) tendons is reported. A total of two UHPC beams prestressed with CFRP tendons were experimentally investigated. On the basis of the fatigue constitutive model of the materials, a fatigue prediction model (FPM) was developed to simulate the flexural fatigue evolvement of the beams. The strain and stress in UHPC and CFRP tendons were calculated by the sectional stress analysis. The influence of steel fiber was considered in the formulae for the crack resistance and crack width, and the midspan deflection was calculated using the sum of deflection before cracking and increment after cracking. The obtained test results were used to verify the FPM. A parametric study was then conducted to analyze the fatigue development of such component, and a formula to predict the flexural fatigue life of UHPC beams under different fatigue loads was proposed.
Improving the NOx reduction performance of an Euro VI d SCR System in real-world condition via nonlinear model predictive control
Authors: Petrillo Alberto , Prati Maria Vittoria , Santini Stefania , Tufano Francesco
Published: December 2021

This paper deals with the possibility of improving the urea dosage control for the Selective Catalytic Reduction Systems (SCR) of an Euro VI d diesel light commercial vehicle in order to increase [Formula: see text] after-treatment reduction performance. To this aim, first, we assess the effective emissions abatement performance for the appraised diesel vehicle via real-world experimental campaign, carried out according to the Real Driving Emissions (RDE) tests on urban, extra-urban and motorway road sections in Naples, Italy. Based on these real-world data, we derive a parameterized control-oriented model for the SCR system which is, then, exploited for the designing of an alternative urea injection logic which could be able to maximize the [Formula: see text] reduction efficiency while minimizing tailpipe ammonia slip. Specifically, the optimal AdBlue injection rate is designed according to a Nonlinear Model Predictive Control Approach which allows obtaining a proper trade-off between the [Formula: see text] abatement and the urea overdosing problem. The effectiveness of the proposed controller is evaluated by comparing the performance assessed for the appraised SCR system during the experimental tests with the ones achievable if the Euro VI diesel would be equipped with the proposed control strategy. Numerical simulation discloses the effectiveness of the NMPC controller in ensuring improved [Formula: see text] reduction with performance complying with the emissions norms, main in avoiding excessive ammonia slip and in guaranteeing a reduced feed ratio w.r.t. to the standard industrial SCR controller mounted on the vehicle.
A novel method to overcome the shortcomings of turbocharging a single cylinder diesel engine
Authors: Ramkumar Jayaraman , Krishnasamy Anand , Ramesh A
Published: December 2021

Single-cylinder diesel engines are generally not turbocharged because of highly pulsating exhaust gas flow, resulting in increased speed fluctuations and reduced turbine performance. In the present work, a novel and simple method is proposed wherein an exhaust plenum is placed before the turbine to reduce the flow fluctuations. A production light-duty naturally aspirated (NA) diesel engine modified into the turbocharged version was incorporated with an exhaust plenum. Steady-state experiments were performed with the base naturally aspirated engine, the turbocharged version without an exhaust plenum (conventional pulse turbocharging), and the turbocharged version with the exhaust plenum. The present work attempts to establish the limitations of conventional pulse turbocharging in a single-cylinder diesel engine unavailable in the existing literature. Though the conventional pulse turbocharged version could deliver a boost pressure of about 2 bar (absolute), a brake power reduction of 40% and the associated drop in brake mean effective pressure was observed compared to the base NA engine due to high exhaust back pressures. The pumping work was four times higher in conventional pulse turbocharging than the NA engine, thus reducing the performance. After validating the simulation models, a one-dimensional simulation tool was used to evaluate the effect of incorporating exhaust plenum before the turbine. Simulated results predicted the brake power output within a 3% error for the NA and plenum turbocharging configurations. An optimal plenum volume was arrived at using the validated simulation model. Subsequent experiments on the turbocharged engine with the plenum in place showed a significant improvement in the engine performance and reduced exhaust emissions compared to the NA version. Brake power output was enhanced by 25%, which indicated improved thermal efficiency of 2%. Compared to the NA version, the soot, carbon monoxide (CO) and unburned hydrocarbon HC emissions were reduced by 93%, 88%, and 53%, respectively. However, an increase in oxides of nitrogen (NOx) emissions was seen, which can be controlled with suitable mitigation methods taking advantage of the significantly lower soot levels. Thus, the proposed method of placing an exhaust plenum before the turbine makes turbocharging viable on single-cylinder diesel engines with performance improvement and emission reduction when suitable NOx mitigation measures are adopted.
A new torsional vibration coupling model for transmission system in diesel generator
Authors: Chen Bin , Hu Yunbo , Guo Yibin , Shuai Zhijun , Liu Chongpei , Li Wanyou
Published: December 2021

The coupling between the crankshaft and the camshaft is neglected before in fault diagnosis which may lead to incomplete fault information. In this paper, a new torsional coupling model of a diesel generator transmission system is proposed for fault diagnosis. The natural frequency and forced torsional vibration response of the model are obtained by the system matrix method and Newmark-β method. For the system without considering the lumped mass of camshafts, some key natural frequencies are lost. The vibration dynamics are compared for the transmission system with and without the new coupling model. And important frequency responses are missed in the spectrums of the forced torsional vibration without the new coupling model. Finally, the new coupling model is implemented in fault diagnosis and the cause of an unusual vibration fault is deduced in the simulation, which confirms the feasibility of the proposed model in fault diagnosis.
Taking deliberative research online: Lessons from four case studies
Authors: Willis Rebecca , Yuille Andy , Bryant Peter , McLaren Duncan , Markusson Nils
Published: December 2021

Researchers using deliberative techniques tend to favour in-person processes. However, the COVID-19 pandemic has added urgency to the question of whether meaningful deliberative research is possible in an online setting. This paper considers the reasons for taking deliberation online, including bringing people together more easily; convening international events; and reducing the environmental impact of research. It reports on four case studies: a set of stakeholder workshops considering greenhouse gas removal technologies, convened online in 2019, and online research workshops investigating local climate strategies; as well as two in-person processes which moved online due to COVID-19: Climate Assembly UK, a Citizens’ Assembly on climate change, and the Lancaster Citizens’ Jury on Climate Change. It sets out learnings from these processes, concluding that deliberation online is substantively different from in-person meetings, but can meet the requirements of deliberative research, and can be a rewarding and useful process for participants and researchers alike.
Enacting settler responsibilities towards decolonisation
Authors: Bell Avril , Yukich Rose , Lythberg Billie , Woods Christine
Published: December 2021

This special issue showcases research exploring the work of settler individuals and groups in support of projects of decolonisation in Aotearoa New Zealand, Australia, Canada and Israel. The papers gathered here were developed from presentations at an international symposium held in Auckland, New Zealand and online in February 2021. As symposium organisers and editors of this collection, we speak and write as settler subjects ourselves, and this collection is situated within the field of Settler Colonial Studies (SCS). This editorial provides an opening framing of the field into which these papers speak, and a survey of some of the key themes within the wider literature. We aim firstly to locate this work within the wider field of scholarship and activism on decolonisation and decoloniality, delimiting the particular focus of decolonisation within settler-dominated contexts. We then discuss the critiques that have been mounted against SCS and some important defences of the field. We argue that while settler colonialism persists, work in SCS has a contribution to make – in highlighting and critiquing settler logics and in identifying changes that it is within the power of settler peoples themselves to make as a contribution towards Indigenous-led decolonisation. Further, we argue that decolonising settler societies must involve settlers learning to be ‘in relation’ with Indigenous worlds and people outside of deeply habituated logics and practices of domination. The papers gathered here provide examples of settler subjects at various points on the path of decolonising themselves and learning the work of ‘being in relation’.
The normal life of settlers
Authors: Svirsky Marcelo
Published: December 2021

This paper concerns Let me tell you a story about Israel, a theatrical play tasked with influencing existing perceptions of the Palestine/Israel conflict amongst international audiences. Drawing on the work of philosopher Baruch Spinoza, I explore the complex issue of how to address the need to change people’s political perceptions by using theatre as a form of activist persuasion. The play attempts to create an image of the conflict mostly absent in the commentaries of international observers who are unaware of the full implications of the conflict’s settler colonial character. Typically, they understand it in terms of two sides competing over land, frontiers and recognition. The sense of balance that this perception conveys pre-empts coming to grips with the colonial history of Palestine beginning with the advent of Zionism from late 19th century. Such a view also obscures the nature of current forms of Israeli domination and fails to take into account a major historical factor: that the settler colonial dynamic in Palestine rests on the ways social life in Israel is organised and reproduced. Hence, the play aims to make perceptible the relation between the social mechanisms of subjectivity formation in the Israeli society on the one hand, and the everyday performance of settler colonial power on the other. Making this relation observable is a necessary step towards rethinking where change could possibly come from.
Modular Endo-Bentall Procedure Using a “Rendez-Vous Access”
Authors: Gandet Thomas , Westermann Dirk , Conradi Lenard , Panuccio Giuseppe , Heidemann Franziska , Rohlffs Fiona , Kölbel Tilo
Published: December 2021

Purpose:

The concept of a single endovascular valve-carrying conduit device was designated endo-Bentall, but published experience is limited to a single case. This technical note describes an alternative modular endo-Bentall technique and a novel access technique to implant it.

Technique:

A 82-year-old woman with chest pain referred for a 10 cm symptomatic aneurysm of the distal arch and descending aorta. An ascending aortic aneurysm of 5.5 cm prevented endovascular aortic arch repair due to lack of a proximal landing zone. The technique is a modular approach combining a physician-modified endograft (PMEG) with 3 large fenestrations for coronary artery perfusion and a transcatheter aortic valve implantation (TAVI). A “rendez-vous access” with a transapical and transfemoral through-and-through wire offered rapid sequential deployment in a modular fashion of both components. The PMEG was deployed first, landing 5 mm deep in the left ventricular outflow tract (LVOT) and the transcatheter aortic valve was implanted few millimeters below. The endo-Bentall procedure was combined with endovascular aortic arch repair.

Conclusion:

A modular endo-Bentall procedure combining a PMEG and TAVI is feasible and adaptable to emergent setting using the “rendez-vous access.”
First Experience With The GoBack-Catheter For Successful Crossing of Complex Chronic Total Occlusions in Lower Limb Arteries
Authors: Bakker Olaf , Bausback Yvonne , Wittig Tim , Branzan Daniela , Steiner Sabine , Fischer Axel , Konert Manuela , Düsing Sandra , Banning-Eichenseer Ursula , Scheinert Dierk , Schmidt Andrej
Published: December 2021

Purpose:

To evaluate the use of the GoBack-catheter (Upstream Peripheral Technologies) in complex revascularizations in lower limb arteries.

Materials and Methods:

In this retrospective single-center study, the results of the first 100 consecutive patients including 101 limb-revascularizations, performed between May 2018 and July 2020 with the study device, were analyzed. In all cases, guidewire-crossing failed, and all lesions were chronic total occlusions (CTO), either de novo, reocclusions, or in-stent reocclusions. Successful crossing was defined as passing the CTO using the study device. Patency at discharge and after 30 days was defined as less than 50% restenosis on duplex sonography, without target lesion revascularization.

Results:

Median lesion length was 24 cm and 38 patients (37.6%) had a calcium grading according to the peripheral arterial calcium scoring system (PACSS) of 4 or 5. In 20.8% of patients, an occluded stent was treated. CTOs involved the femoropopliteal segment in 91.1%, iliac arteries in 5.9%, and tibial arteries in 7.9%. The GoBack-catheter was employed for entering into or crossing through parts or the full length of a CTO or an occluded stent as well as for re-entering into the true lumen after subintimal crossing. The device was used via contralateral and ipsilateral antegrade as well as retrograde access with an overall technical success rate of 92.1%. In 3 patients minor bleeding occurred at the crossing or re-entry site, which were managed conservatively. Thirty-day adverse limb events comprised minor amputations in 4 patients (4.0%), 1 major amputation (1.0%), and reocclusions in 7 limbs (6.9%).

Conclusion:

The new GoBack-catheter offers versatile endovascular applicability for complex CTO recanalization in a broad range of peripheral vascular interventions with a high technical success and low complication rate.
Opening or Impasse? Critical Media Literacy Pedagogy in a Posttruth Era
Authors: Tebaldi Catherine , Nygreen Kysa
Published: December 2021

Critical media literacy (CML) education is an approach to teaching about power, ideology, and hegemony through media. As a critical intervention in mainstream media literacy education, CML education integrates a cultural studies lens with a critical pedagogy orientation. In this article, we use critical auto-ethnography and personal reflective narratives or “anti-biography” to explore the dynamics and tensions of teaching CML in the posttruth era. We locate the shift to posttruth in the 2016 U.S. presidential campaign and election of Donald Trump, which produced a resurgence in far-right discourses promoting distrust of media and state institutions. We show how this shift created openings to criticality that made teaching CML easier in some ways; however, as we look deeper, what appears as an opening may in fact be an impasse. Through personal narratives, we illustrate what these openings and impasses looked like, how they felt and how they played out, to theorize about the possibilities and tensions of teaching CML in the current political moment. We argue the posttruth era necessitates a change in how we teach CML but not, as commonly argued, by teaching students how to fact-check or identify reliable sources. Instead, we must learn and teach about how the right uses media in transgressive ways to promote and normalize a racist, sexist, and authoritarian political agenda. We must also work to better understand students’ experiences of economic precarity and the limits of neoliberal multiculturalism.
The Dyslexia Marker Test for Children: Development and Validation of a New Test
Authors: Nergård-Nilssen Trude , Friborg Oddgeir
Published: December 2021

This article describes the development and psychometric properties of a new Dyslexia Marker Test for Children (Dysmate-C). The test was designed to identify Norwegian students who need special instructional attention. The computerized test includes measures of letter knowledge, phoneme awareness, rapid automatized naming, working memory, decoding, and spelling skills. Data were collected from a sample of more than 1,100 students. Item response theory (IRT) was used for the psychometric evaluation, and principal component analysis for checking uni-dimensionality. IRT was further used to select and remove items, which significantly shortened the test battery without sacrificing reliability or discriminating ability. Cronbach’s alphas ranged between .84 and .95. Validity was established by examining how well the Dysmate-C identified students already diagnosed with dyslexia. Logistic regression and receiver operating characteristic (ROC) curve analyses indicated good to excellent accuracy in separating children with dyslexia from typical children (area under curve [AUC] = .92). The Dysmate-C meets the standards for reliability and validity. The use of regression-based norms, voice-over instructions, easy scoring procedures, accurate timing, and automatic computation of scores make the test a useful tool. It may be used as part of a screening procedure, and as part of a diagnostic assessment. Limitations and practical implications are discussed.
The Impact of Risk Assessment on Juvenile Justice Decision-Making and New Adjudication: An Analysis of Usage and Outcome
Authors: Petkus Amber A. , Sullivan Christopher J. , Lugo Melissa , Newsome Jamie
Published: December 2021

Juvenile risk and needs assessments (JRNAs) have been the focus of extensive research in the academic literature. Prior studies have primarily focused on the risk-recidivism relationship and establishing predictive validity with juvenile populations. Less investigated is the use of risk and need assessment in practice, including how such tools are used to inform decision-making. This study uses record data encompassing 3,034 youth from a multi-state study to examine dispositional and treatment decisions associated with the Ohio Youth Assessment System (OYAS). Specifically, mediation analyses were conducted to evaluate how current practices align with underlying logic and theory regarding the role of assessments in juvenile justice. Findings reveal varied and complex relationships between assessment scores, case decisions, and recidivism. While risk was generally associated with recidivism, our results suggest juvenile risk and need assessments are inconsistently used to inform case management and placement decisions. Implications for practice and future research are also discussed.
Past challenges and the future of discrete event simulation
Authors: Collins Andrew J , Sabz Ali Pour Farinaz , Jordan Craig A
Published: December 2021

The American scientist Carl Sagan once said: “You have to know the past to understand the present.” We argue that having a meaningful dialogue on the future of simulation requires a baseline understanding of previous discussions on its future. For this paper, we conduct a review of the discrete event simulation (DES) literature that focuses on its future to understand better the path that DES has been following, both in terms of who is using simulation and what directions they think DES should take. Our review involves a qualitative literature review of DES and a quantitative bibliometric analysis of the Modeling and Simulation (M&S) literature. The results from the bibliometric study imply that demographics of the M&S community are rapidly changing, both in terms of the nations that use M&S and the academic disciplines from which new simulationists hail. This change in demographics has the potential to help aid the community face some of its future challenges. Our qualitative literature review indicates that DES still faces some significant challenges: these include integrating human behavior; using simulation for exploration, not replication; determining return on investment; and communication issues across a splitting community.
Weight and configuration optimization of the launcher pod using finite element analysis
Authors: Dewangan Mithilesh Kumar , Panigrahi S K
Published: December 2021

This paper deals with the stress analysis of the launcher pod based on optimization of its configuration and weight without compromising its strength and stiffness. The launcher pod assembly is a complex fabricated structure, which is subjected to a variety of dynamic loads during firing of rockets. A series of finite element simulations reveal the critical location of the pod for different loading conditions based on the stress magnitude, which helps to optimize its weight and configuration of the launcher pod. It has been observed that the optimized weight of the given launcher pod after modification of materials and configuration, with the provided materials, loading, and boundary conditions, is reduced by 36.27% (without launcher tubes and rockets) against the initial weight of the launcher pod.
Comparative Study of 2 Bone Anchors Using a Limited Open Procedure for the Management of Distal Radioulnar Joint Instability
Authors: Monsivais Jose J. , Herber Agustin , Charest Guy , Ogunleye David , Weaver Mitchell
Published: December 2021

Background:

Arthroscopic and open surgical procedures are commonly used to repair distal radioulnar joint (DRUJ) instability. Both may result in patient dissatisfaction and recurrence of DRUJ instability. An alternative treatment that yields improved outcomes is a limited open approach using a bone anchor to support the DRUJ.

Methods:

A retrospective chart review of 58 patients (59 extremities) aged 18 to 60 years with type 1B Palmer rupture (3 months or more after injury) of the triangular fibrocartilage complex (TFCC) without distal radius fracture was conducted. Inclusion criteria are: 3 to 12 months after injury, clinical DRUJ instability, and minimum of 6 months of postoperative follow-up. Operative fixation with Stryker Sonic or Depuy Mitek anchor was done by the same surgeon using a limited open procedure. Preoperative and postoperative assessments included Disability of the Arm, Shoulder, and Hand; Brief Pain Inventory; Wong-Baker FACES Pain Rating Scale; Numeric Pain Scale; range of motion; and recurrence of instability. A multivariate analysis of variance model was fit to imputed data to assess the effect of both anchors.

Results:

Clinical and statistical differences were found in preoperative and postoperative assessments for either the Stryker Sonic or the Depuy Mitek anchor but not between anchor types. There was no recurrence after 3 years with either anchor.

Conclusion:

Patients requiring TFCC repair using the Stryker Sonic or Depuy Mitek anchor experienced: (1) significant clinical and statistical improvement in postoperative assessments; (2) patient satisfaction; and (3) corrected DRUJ instability. Consequently, major determinants in deciding which bone anchor to use may be based on cost or surgeon’s preference.
A National Survey of Hand Surgeons: Understanding the Rural Landscape
Authors: Meyerson Joseph , Liechty Andrew , Shields Tyler , Netscher David
Published: December 2021

Background:

Twenty percent of the US population is described as being rural and may have limited access to hand surgeons, especially on an emergency basis. Little is known about case type, call hours, employment status, and other relevant details of rural hand surgery.

Methods:

We surveyed members of the American Society of Surgery for the Hand to begin to describe the problem.

Results:

There were 471 responses from 2256 members surveyed with 387 completing 100% of questions asked. Ninety (19%) identified themselves as primarily located in a rural population and 381 (81%) in a metropolitan region. In our study, rural hand surgeons were more likely to be employed by a community hospital, followed by independent private practice, multispecialty group, academics, and then locum tenens. Rural surgeons’ practices were 80% solely hand surgery, while metropolitan surgeons’ practices were 89% ( P < .01). Metropolitan surgeons felt that of the transfers from rural facilities, 46% did not need emergency hand care and that 60% of the time, there was not actually a need for specialty hand surgery care.

Conclusions:

Our survey begins to shed light on the details of rural hand surgery practice. We found that rural surgeons are more likely to be employed in community hospitals and take more call. When available, hand surgery specialists could prevent unnecessary transfer of patients to metropolitan areas. More work needs to be done to describe the differences between rural and metropolitan hand surgery practices as well as create rural hand surgeons.
The Transosseous Internal Four Strand Technique: A New All-Inside Technique for Zone 1 Flexor Tendon Repairs
Authors: Harenberg Patrick S. , Grünert Jörg G. , Christen Samuel M.
Published: December 2021

Background:

Multiple techniques for the repair of flexor tendon injuries in zone 1 have been proposed over time. While pull-out suture techniques and bone anchor seem to be stronger than internal suture techniques, they are associated with a higher complication rate. We therefore developed an alternative internal suture repair with similar biomechanical stability to those of pull-out sutures and bone anchors.

Methods:

Twenty porcine distal phalanges and deep flexor tendons were randomized to 2 groups of 10 each. The tendons were transsected at the level of the distal interphalangeal joint. In group 1, repairs were performed with a well-established intraosseous suture repair and in group 2 with our new multistrand technique. The repairs were biomechanically tested with linear distraction until failure.

Results:

We recorded a significantly higher 2-mm gap force (2GF)—and thus higher stability—of the repairs in group 1 in comparison to group 2. With a 2GF of more than 50 N, our suture technique allows for a modern early active motion rehabilitation protocol. Breakage of the suture construct occurred at random places in the repair in both groups. No pull-outs were noted.

Conclusions:

This study presents a strong transosseous multistrand repair technique for flexor tendon repair in zone 1 that is simple and fast to perform and should have enough strength to withstand early active motion rehabilitation.
Surgical Treatment for Recurrent Dupuytren Disease
Authors: Hozack Bryan A. , Rayan Ghazi M.
Published: December 2021

Background:

Revision procedures for recurrent Dupuytren disease (DD) can be difficult and carry a high risk of complications. Our goal was to describe surgical strategies used for cases of recurrence and report on their outcomes.

Methods:

We reviewed 1 surgeon’s operative cases for recurrent DD performed at 1 institution. Prior procedures included collagenase injection, percutaneous needle fasciotomy, or open surgical fasciectomy in the same digit or area of the hand.

Results:

From January 1981 to December 2020, 54 procedures were performed on 33 patients for recurrent DD. Most patients were men (82%), had bilateral involvement (64%) and family history (52%), and some had ectopic disease in their feet (24%). The small finger was involved in 76% of the cases, and the proximal interphalangeal (PIP) joint was involved in 83% of these digits. The procedures included 38 partial fasciectomies (72%), 12 dermofasciectomies (23%), 3 radical fasciectomies (6%), 1 of each needle fasciotomy, ray amputation, and PIP joint arthrodesis (2%). Twenty-three patients (43%) required full thickness skin grafts with an average area of 7.1 cm2 (range: 1-20 cm2).

Conclusions:

This study highlights the complexity of recurrent DD case management and found the treatment required for 95% of patients in this series was open partial fasciectomy with or without demofasciectomy. Full thickness skin grafting was necessary in nearly half of the cases.
Does the Nail Bed Regenerate?
Authors: Silva Jefferson Braga , Magnus Gabriela A. , Stanham Valentina , Wolff Cecília G. , Aranchipe Carolina S. , Cauduro Carolina
Published: December 2021

Background:

The regenerative potential of the nail bed after trauma remains controversial.

Methods:

We performed a retrospective review of 51 patients who underwent nail bed reconstruction with 2 techniques (direct flow island flap or a Tranquilli-Leali “Atasoy” flap) due to trauma involving the nail bed complex. These 2 flaps were used to support the loss of distal substance and to allow the regeneration of the nail bed. Outcomes were analyzed for at least 18 months. There were 34 men (66.7%), and the average age was 16.1 years. Most patients (56.9%) had crush injuries. The little (16) and index (14) fingers were the most affected. Twenty-seven were children (range: 4-11) with an average age of 7.4 ± 1.9 years. The middle finger was the most affected (29.2%).

Results:

The outcomes were good to excellent in 41 operated patients (80.4%). Hook nail was absent in 84.3% of the patients. Most patients (98%) did not develop necrosis. Children had an excellent/good outcome rate of 85.2%, while in adults, the rate was 75% of cases ( P = .485).

Conclusion:

The direct flow island flap is superior in terms of outcome, regardless of age, sex, affected finger, dominant hand, type of trauma, and injury zone. In cases where there was a correct reconstruction of the hyponychium, there was regeneration of the nail bed.
Nerves in Continuity Following Hand Trauma: A Descriptive Report
Authors: Pereira Daniel E. , Desai Mihir J.
Published: December 2021

Background:

Understanding the clinical presentation of nontransected nerve injuries in acute hand trauma/wrist trauma will help in early intervention, which is vital for maximizing return of function in patients. This retrospective study evaluated patients who experienced traumatic hand injuries with nerve in continuity within the zone of injury.

Methods:

This was a single-center retrospective chart review of 20 patients with hand or wrist trauma resulting in damage to bone, tendon, or soft tissues within Zones II to V. Patients were 18 to 70 years of age and had documented visualization of at least one nerve within the zone of injury at the time of surgery but no documented full or partial nerve transection. The cohort was characterized using descriptive statistics including mechanism of injury, extent of strength and sensation deficits, and outcomes. Resolution of symptoms was defined as full, partial, or none.

Results:

Of the 20 patients included in the study, 15 patients (75%) showed symptoms of impaired nerve function either prior to surgery or at the first post-surgical follow-up visit. Without direct nerve treatment, only 23% (3/13) of patients experienced full recovery based on qualitative sensory assessment. However, patients reporting pain after surgery (57%; 8/14) showed full recovery from pain despite no direct nerve treatment.

Conclusions:

In our retrospective cohort of patients with hand/wrist trauma that presented with an intact nerve in continuity, we found that a majority showed symptoms of nerve injury. Further, these patients showed slow recovery over time with a minority achieving partial or full recovery or improvement in pain.
Impact of renal chimney intra-aortic stent length on branch and end-stent angle in chimney endovascular aneurysm repair and endovascular aneurysm sealing configurations
Authors: Ullery Brant W , Suh Ga-Young , Thompson Patrick , Lee Jason T. , Holden Andrew , Dalman Ronald L. , Cheng Christopher P
Published: December 2021

Objective

Practice patterns and durability of parallel stent graft techniques in complex endovascular aneurysm repair (EVAR) remain poorly defined. We aimed to quantify and compare the impact of renal chimney intra-aortic stent length (IASL) on geometric deformations of renal arteries in complex EVAR.

Methods

Thirty-eight nonconsecutive patients underwent EVAR utilizing parallel stent graft techniques (chimney EVAR [chEVAR], n = 28; chimney endovascular aneurysm sealing [chEVAS], n = 10) between 2010 and 2016. A total of 59 renal chimney stent grafts were used. Geometric quantification was derived from three-dimensional model-based centerline extraction. Renal chimney intra-aortic stent length (IASL) was defined as the length of chimney stent that extended from the proximal edge of the chimney stent to the ostium of the corresponding renal artery.

Results

Mean IASL for both left and right renal arteries in the cohort was 35.7 mm. Renal arteries containing chimney IASL <30 mm trended toward a greater branch angle (135.4 vs. 127.8°, p = .06). Left renal arteries showed significantly greater branch angle among those with IASL <40 mm (135.5 vs. 121.7°, p = .045). Mean IASL for renal arteries in chEVAR was significantly longer compared to chEVAS (39.2 vs. 26.3 mm, p = .003). No difference was noted in overall branch angle or end-stent angle based on procedure type. ChEVAR with IASL <30 mm had significantly greater end-stent angle (48.2 vs. 33.5°, p = .03). In contrast, chEVAS patients showed no difference in end-stent angle based on IASL thresholds, but did have significantly greater branch angle among those with IASL <30 mm when grouped by both all renal arteries (133.5 vs. 113.5°, p = .004) and right renal arteries (134.3 vs. 111.6°, p = .02).

Conclusions

Renal chimney stents with longer IASL appear to exhibit less renal artery deformation, suggesting a more gradual and perpendicular transition of the chimney stent across the renal ostium.
Impact of COVID-19 on perceived wellbeing, self-management and views of novel modalities of care among medically vulnerable patients in Singapore
Authors: Yoon Sungwon , Hoe Pei Shan , Chan Angelique , Malhotra Rahul , Visaria Abhijit , Matchar David , Goh Hendra , Seng Bridget , Ramakrishnan Chandrika , Koh Mariko S , Yee Tiew Pei , Nadarajan Gayathri Devi , Bee Yong Mong , Graves Nicholas , Jafar Tazeen H. , Ong Marcus EH
Published: December 2021

Objectives

This study aims to examine the impact of COVID-19 measures on wellbeing and self-management in medically vulnerable non-COVID patients and their views of novel modalities of care in Singapore.

Methods

Patients with cardiovascular disease (CVD), respiratory disease, chronic kidney disease, diabetes and cancer were recruited from the SingHealth cluster and national cohort of older adults. Data on demographics, chronic conditions and perceived wellbeing were collected using questionnaire. We performed multivariable regression to examine factors associated with perceived wellbeing. Qualitative interviews were conducted to elicit patient's experience and thematically analyzed.

Results

A total of 91 patients participated. Male patients compared with female patients perceived a lower impact of the pandemic on subjective wellbeing. Patients with CVD compared to those having conditions other than CVD perceived a lower impact. Impacts of the pandemic were primarily described in relation to emotional distress and interference in maintaining self-care. Hampering of physical activity featured prominently, but most did not seek alternative ways to maintain activity. Despite general willingness to try novel care modalities, lack of physical interaction and communication difficulties were perceived as main barriers.

Discussion

Findings underline the need to alleviate emotional distress and develop adaptive strategies to empower patients to maintain wellbeing and self-care.
Factors influencing postoperative pain management among nurses in selected district hospitals in Ghana
Authors: Menlah Awube , OseiAppiah Evans , Garti Isabella , Frempomaa Agyare Dorcas
Published: December 2021

Background:

Poorly managed postoperative pain is linked to numerous postoperative complications worldwide and in Ghana. This is due to the myriad of physical and psychological problems, such as lifelong chronic pain syndromes, impaired functionality and death.

Purpose:

The aim of this study was to assess the barriers and factors influencing postoperative pain management by Ghanaian nurses working in four hospitals.

Methods:

A quantitative descriptive cross-sectional design was employed for this study. Participants were recruited using a multistage sampling technique by which 146 returned their questionnaires out of 194 participants. The statistical analysis of data was done with the Statistical Package of Social Sciences (SPSS) 20.0 version.

Results:

Findings revealed that some verbal and non-verbal cues from patients such as facial grimacing, restlessness, irritability and distress, lack of concentration and moaning or crying (verbalisation) influenced how nurses controlled postoperative pain with analgesia. The participants also identified several barriers to influence postoperative pain management by nurses.

Conclusion:

In conclusion, postoperative pain control by nurses is influenced by several factors, and hence, nurses need to manage patients’ pain effectively in Ghana and abroad using multiple approaches.
Composition of nests constructed by species in the Motacillidae, Sylviidae and Prunellidae
Authors: Dickinson Amy M , Locke Emily , Gray Liberty A , Bennett Sophie L , Biddle Lucia E , Goodman Adrian M , Deeming Denis Charles
Published: December 2021

Bird nests can be complex bio-engineered structures constructed from a range of materials to provide a site for incubation, and in many species chick rearing. Reports of the materials used in nest walls and cup linings are typically qualitative and do not assist in understanding the functional properties of the structure as a whole. This paper provides size and composition data for nests from four species of the Motacillidae family: the meadow pipit ( Anthus pratensis), pied wagtail ( Motacilla alba), grey wagtail ( Motacilla cinerea), and the yellow wagtail ( Motacilla flava), three species of the Sylviidae family: willow warbler ( Phylloscopus trochilus), Eurasian reed warbler ( Acrocephalus scirpaceus) and Eurasian blackcap ( Sylvia atricapilla), and the dunnock ( Prunella modularis) of the Prunellidae family. Three hypotheses were tested: do nest dimensions correlate with body mass? Is it possible to distinguish among species based on their nest composition; and for individual species? Is it possible to distinguish between the cup lining and outer nest wall based on the materials used in construction? Nest composition and size varied among species although the degree of intra-specific variation was different. Size of a nest was unrelated to average female adult body mass. Composition relied on similar types of materials but in differing quantities between species. It was possible to distinguish among species in terms of nest construction, and between the cup lining and the outer nest, on the basis of at least one of the component materials. By providing quantitative data on composition, it may be possible in the future to understand better the structural, insulative and hydrological properties of the nest. Such information will be invaluable as we begin to develop an understanding of the factors that have driven evolution of nest architecture.
Men’s Voices: Black and White Aspiring Principals Reflect on Their Preparation to be Racial Equity Leaders
Authors: Rasmussen Natalie , Raskin Candace
Published: December 2021

This phenomenological study examined the racial identity development of Black and White men—aspiring school leaders—who had recently completed a principal preparation program as members of a racially diverse cohort of students. The principal preparation program was designed with an unapologetic emphasis on race and addressing issues of racism. The study found that making race and issues of racism a focal point of all curriculum and pedagogy increased participants’ racialized realization and produced Black and White male aspiring principals who felt prepared to lead schools through the lens of racial equity.
Dynamic bearing capacity of point fixed corrugated metal profile sheets subjected to blast loading
Authors: Fischer Kai , van der Woerd Jan Dirk , Harwick Wilfried , Stolz Alexander
Published: December 2021

Blast loading scenarios and the corresponding hazards have to be evaluated for infrastructure elements and buildings especially at industrial sites for safety and security issues. Point fixed corrugated metal sheets are often applied as façade elements and can become a hazard for humans if they are pulled off.

This paper investigates the dynamic bearing capacity of such structural members in terms of their general bending behavior in the middle of the span and pull-out behaviors at the fixing points. The elements are fixed at two sides and the load transfer is uniaxial. An experimental series with static and dynamic tests forms the basis to identify the predominant failure modes and to quantify the maximum stress values that can be absorbed until the investigated structural members fail.

The experimental findings are applied to create and to optimize an engineering model for the fast and effective assessment of the structural response. The aim is the derivation of a validated model which is capable to predict the blast loading behavior of metal sheets including arbitrary dimensions, material properties, and screw connections. Results of this study can be integrated into a systematic risk and resilience management process to assess expected damage effects and the evaluation of robustness.