bluuebunny/crossref_metadata_2025 huggingface dataset:
An identification algorithm of driver steering characteristics based on backpropagation neural network
Authors: Zhao Shangyu , Chen Guoying , Hua Min , Zong Changfu
Published: August 2019

This paper presents a novel identification method of driver steering characteristics based on backpropagation neural network. First, a driving simulator is built to collect required driving data. After careful analysis, three feature parameters that reflect driver steering characteristics are determined, including the average steering wheel angular speed, the standard deviation of the steering wheel angle, and the average vehicle longitudinal speed. Then, steering feature parameter vectors are extracted from raw data and clustered by the K-means algorithm. According to the clustering result, driver steering characteristics are divided into three types: cautious, average, and aggressive. Subsequently, a backpropagation neural network with two hidden layers is designed and trained to identify the types of feature parameter vectors. Verification results show that the established backpropagation neural network has high identification accuracy and good generalization ability for the identification of driver steering characteristics.
Robust H∞ state-feedback control for path following of autonomous ground vehicle based on lateral velocity estimation
Authors: Feng Pengpeng , Zhang Jianwu , Yang Weimiao
Published: August 2019

A robust [Formula: see text] observer-based static state-feedback controller is designed for the path following of autonomous ground vehicles in this paper. Considering the lateral velocity of vehicle is usually difficult to measure, an observer is designed to estimate the value of lateral velocity first. Then, a robust controller is proposed to cope with the modeling uncertainty and disturbance, such as the variation of road coefficient and lateral disturbance. Numerical simulations using a high-fidelity and full-vehicle model based on a CarSim–Simulink joint platform have verified the effectiveness of the proposed approach.
Semi-cascade network for driver’s distraction recognition
Authors: Hu Jun , Liu Wei , Kang Jiawen , Yang Wenxing , Zhao Hong
Published: August 2019

A novel method for the eight most common driver’s distraction actions recognition is presented in this paper. To this end, a semi-cascade network (SCN) with very lightweight architecture is designed. The approach recognizes the morphology of the human face and hands to make judgments about the driver’s actions rather than just judging facial information. In order to subdivide similar actions, a SCN structure which effectively reduces the network’s scale is employed. A joint training approach is proposed for training the network and achieving 95.61% accuracy. In addition, to verify the validity of the method, a dataset containing 100,000 samples is created. Finally, a warning strategy is provided for our system and 93.9% warning rate for the driver’s distraction behavior is achieved.
Who are the civilians in the wars of South Sudan?
Authors: Kindersley Nicki , Rolandsen Øystein H
Published: August 2019

This longitudinal study explores the place of the civilian populations in the wars of what is now South Sudan. Using a broad range of empirical evidence, we trace the evolution of conflict practices and norms from the 1800s to today. Two main insights stand out: First, since the initial colonial incursions, local residents have been strategic assets to be managed and exploited, and thus populations are not just legitimate targets in conflicts but also key resources to capture and control. Second, violent governance structures and practices have been created and reformed through these generations of coercive rule and civil wars. These two issues have undermined, and redefined, the distinction between military and civilian actors. This analysis does not excuse the massive and systematic violence against the general population of these countries. However, without due consideration of these deeply engraved historical systems and logics of violent governance, today’s brutal conflicts become incomprehensible, and there is a significant risk that international approaches to mitigating this violence – such as Protection of Civilians camps – become incorporated into these systems rather than challenging them.
Tracing the dune activation of Badain Jaran Desert and Tengger Desert by using near infrared spectroscopy and chemometrics
Authors: Zhang Xin , Liu Panpan , Pan Baolin , Wei Mingjian , Zhang Zhuoyong
Published: August 2019

Tracing the sand source is helpful to interpret the evolution of deserts and explain the relations between the desert and the climatic geographical condition around. Furthermore, it is helpful to investigate the reasons for sandstorms in corresponding areas. In this work, near infrared spectroscopy combined with hierarchical cluster analysis was proposed as a novel method to characterize sand samples collected from Badain Jaran and Tengger Deserts, two main sources of sandstorms in North China. Partial least square discriminant analysis gives a classification result with an accuracy of 100% for the estimation of hierarchical cluster analysis. The results provide support that Badain Jaran Desert and Tengger Desert have sand exchanged by monsoonal weather events. The transmission between the two deserts is also affected by the local terrain. The sand samples were also analyzed by electron microscopy, energy dispersive spectroscopy and Fourier transform infrared spectroscopy to investigate the sample differences in morphology, elemental contents and molecular structures. Near infrared spectroscopy combined with chemometric methods has the potential to be used for the identification of sand samples to determine the sources of sands with advantages of fast, nondestructive, low cost and in situ analysis.
Cultural Influences on Childhood Obesity in Ethnic Minorities: A Qualitative Systematic Review
Authors: Chatham Rebecca E. , Mixer Sandra J.
Published: August 2019

Introduction: Childhood obesity remains an unrelenting public health problem disproportionately affecting ethnic minorities. Although research has examined ethnicity as a factor of childhood obesity, few studies have examined cultural influences. The purpose of this systematic review was to examine the qualitative evidence of cultural influences on childhood obesity in ethnic minority groups. Methodology: Selective sampling of studies since 2008 yielded 251 articles. Twelve articles that addressed cultural influences on childhood obesity were identified for review. The Culture Care Theory Sunrise Enabler factors were used as an a priori framework for theme coding. Results: Nine themes emerged: child feeding, family, gender roles, food, healthy child appearance, physical activity, sedentary activity, food cost, and obesogenic environment. Discussion: Cultural care practices such as traditional foods and family meals are protective factors in childhood obesity and should be encouraged by nurses caring for and working with ethnic minority populations.
Fibular Nail Fixation: Topical Review
Authors: Bäcker Henrik C. , Vosseller J. Turner
Published: August 2019

Background:

Intramedullary implants have been used historically in long bone fractures with success. In recent years, a variety of intramedullary implants for the treatment of fibular fractures have been investigated. These various implants have not been assessed together in a cohesive manner. In this review, we assess implants used for intramedullary fixation of fibular fractures with respect to implant design and clinical results.

Methods:

A comprehensive systematic literature review for intramedullary implants in fibular fractures was performed. All publications that assessed intramedullary fibular implants were reviewed. In total, 11 different intramedullary nails were found. Clinical results obtained from these studies were reviewed.

Results:

The intramedullary implants used for fibular fracture fixation generally fell into one of 3 categories: an unlocked longitudinal strut, an implant roughly equivalent to a large screw, or a more traditionally locked intramedullary nail. Reported clinical results were generally good, although inconsistent outcome reporting greatly limited comparison between studies. Complication rates varied with the implants but were generally low.

Conclusion:

Intramedullary implants for fibular fracture stabilization have changed over the years to improve stability. Although clinical results are limited, data suggest that these implants are safe and can potentially approximate more traditional implants.

Level of Evidence:

Level II, systematic review.
Ankle Motion and Offloading in Short Leg Cast and Low and High Fracture Boots
Authors: Nahm Nickolas , Bey Michael J. , Liu Serena , Guthrie S. Trent
Published: August 2019

Background:

Short leg casts (SLCs) and fracture boots are used to treat foot and ankle injuries, but the decision to use one device over the other is often subjective. This study compared the impact of SLCs and low and high fracture boots on ankle motion and offloading.

Methods:

Twenty healthy adults were prospectively studied. High-speed dynamic radiography was utilized to determine tibiotalar range of motion in the sagittal plane during nonweightbearing (NWB) and weightbearing (WB) gait in a shoe (control), SLC, and low and high fracture boots. Sensors captured peak plantar surface forces to determine ankle offloading.

Results:

In NWB, the low fracture boot (2.2 ± 2.0 degrees), high fracture boot (2.3 ± 1.6 degrees), and SLC (2.3 ± 1.5 degrees) had significantly less motion compared with the control (3.6 ± 2.1 degrees; P ≤ .026). During WB, the SLC (3.4 ± 1.4 degrees) and high fracture boot (4.8 ± 2.0 degrees) had less motion compared with the low fracture boot (7.8 ± 3.4 degrees; P < .001). Finally, the SLC (172.6% ± 48.3% body weight [BW]) and low fracture (165.1% ± 36.2% BW) and high fracture (154.5% ± 32.9% BW) boots were associated with less peak plantar surface force compared with the control (195.0% ± 43.8% BW; P ≤ .087).

Conclusion:

The SLC and high fracture boot immobilized the ankle in NWB and offloaded and immobilized the ankle in WB. The low fracture boot also immobilized the ankle in NWB, but in WB, the low fracture boot only offloaded the ankle and did not immobilize it.

Clinical Relevance:

The low fracture boot may be more suited for NWB or possibly immobilizing the foot in WB.
Clinical Results of Bioabsorbable Pin Fixation Relative to the Bone Condition for Osteochondral Lesion of the Talus
Authors: Nakasa Tomoyuki , Ikuta Yasunari , Ota Yuki , Kanemitsu Munekazu , Adachi Nobuo
Published: August 2019

Background:

Fixation of an osteochondral lesion of the talus (OLT) can restore the natural congruency of the joint surface with hyaline cartilage. In this procedure, the bone condition of the osteochondral fragment is important for stabilizing the lesion, and it may affect clinical outcomes. The aim of this study was to explore the influence of the fragment’s bone condition on clinical outcomes.

Methods:

Eighteen ankles in 17 patients with a mean age of 20.1 years, which had undergone fixation of an OLT using bioabsorbable pins, were included. Based on the fragment’s bone condition on preoperative computed tomography scans, ankles were divided into 3 groups: normal, segmentation, and absorption. The American Orthopaedic Foot & Ankle Society (AOFAS) scale and magnetic resonance imaging (MRI) findings were evaluated both pre- and postoperatively. Second-look arthroscopic findings were evaluated in 15 ankles and were compared with biopsy specimens from the initial surgery.

Results:

The AOFAS scale significantly improved at the final follow-up in all groups with no significant differences among the 3 groups. MRI at 1 year showed good bone incorporation and a congruent cartilage surface in all groups, but the bone marrow lesion in the absorption group was significantly larger than that in the other groups. In second-look arthroscopy, all ankles showed stable and near-normal cartilage. There was no significant correlation between arthroscopic and histological findings.

Conclusion:

We found that fixation can be considered when there is a good cartilage surface on a large OLT, even if bone absorption in the fragment exists.

Level of Evidence:

Level III, comparative study.
Reliability of colour perimetry to assess macular pigment optical density in age-related macular degeneration
Authors: Coco-Martín Rosa M , Pichel-Mouzo María , Fernández Itziar , Plata-Cordero María , Lopez-Miguel Alberto
Published: August 2019

Background:

The aim of this study was to determine the intra-session repeatability and inter-examiner reproducibility of the colour perimetry technique when assessing in vivo macular pigment optical density in age-related macular degeneration patients.

Methods:

Age-related macular degeneration patients were classified into four groups: early age-related macular degeneration, intermediate age-related macular degeneration, atrophic age-related macular degeneration and neovascular age-related macular degeneration after undergoing fundus photography (TRC 50DX type IA) and spectral-domain optical coherence tomography analysis (Topcon 3D-2000). Central fixation was confirmed in all patients using the MP-1 microperimeter (Nidek, Padua, Italy). To analyse repeatability, one examiner obtained three consecutive macular pigment optical density measures with MonCV3 device (Metrovision, Perenchies, France). To study agreement between two observers, a second examiner performed another macular pigment optical density measurement in random order. Within-subject standard deviation, coefficient of variation, and intraclass correlation coefficient data were obtained.

Results:

Fifty two (32 females and 20 males) consecutive age-related macular degeneration patients having a mean age of 71.5 ± 8.2 years were recruited. Six had early age-related macular degeneration, 25 had intermediate age-related macular degeneration, 10 had atrophic age-related macular degeneration and 11 had neovascular age-related macular degeneration. For repeatability, coefficient of variation values ranged from 22.3% (neovascular age-related macular degeneration) to 41.0% (atrophic age-related macular degeneration) and intraclass correlation coefficient values from 0.52 (intermediate age-related macular degeneration) to 0.79 (neovascular age-related macular degeneration). For agreement between two examiners, coefficient of variation values ranged from 20.1% (intermediate age-related macular degeneration) to 37.8% (neovascular age-related macular degeneration) and intraclass correlation coefficient values from 0.61 (neovascular age-related macular degeneration) to 0.80 (atrophic age-related macular degeneration).

Conclusion:

The reliability (intra-session repeatability and inter-examiner reproducibility) of colour perimetry technique to assess macular pigment optical density in age-related macular degeneration patients is only moderate. Thus, it cannot be recommended to be performed when evaluating and monitoring age-related macular degeneration patients in the daily clinic.
Cannulation practices at haemodialysis initiation via an arteriovenous fistula or arteriovenous graft
Authors: Hill Kathleen , Sharp Rebecca , Childs Jessie , Esterman Adrian , Le Leu Richard , Juneja Rajiv , Jesudason Shilpa
Published: August 2019

Introduction:

A functioning long-term vascular access is required for haemodialysis therapy; however, establishing this can be challenging in the setting of advanced age and vessels damaged by diabetes. Complications include the inability to insert two needles for the treatment resulting in miscannulation trauma and in some cases insertion of a temporary central venous access device. The broad objective of this review is to define the evidence base regarding cannulation practices in the initiation of haemodialysis via an arteriovenous fistula or an arteriovenous graft.

Methods:

This review uses the framework recommended by the Joanna Briggs Institute and the process by which papers were included or excluded followed the standard Preferred Reporting Items for Systematic Reviews and Meta-Analyses group approach. A total of 20 primary research studies met the inclusion criteria.

Results:

Cannulation in the 10- to 15-week period rather than delaying past this time frame is associated with the best outcomes. New vascular access given time to mature through single-needle haemodialysis treatments may improve long-term patency. Duplex ultrasound mapping prior to initiation of cannulation supports the clinical decision-making process on timing of and selection of cannulation sites.

Conclusion:

Cannulation trauma at the initiation of haemodialysis could potentially be reduced with a strategy of incremental haemodialysis using single-needle treatment supported with duplex ultrasonography assessment to ‘map’ the vascular access as a guide for clinicians prior to cannulation initiation.
The Correlation Between Preoperative Findings of High-Resolution Computed Tomography (HRCT) and Intraoperative Findings of Chronic Otitis Media (COM)
Authors: Aljehani Mariam , Alhussini Rayan
Published: August 2019

Objectives:

The aim of this study was to investigate the correlation between the preoperative findings of high-resolution computed tomography (HRCT) of temporal bone in chronic otitis media (COM) and the intraoperative findings.

Methods:

This retrospective study was conducted in the ORL-HNS Unit at Ohud Hospital, Medina, Saudi Arabia, during the period from January to September 2018. We included all patients with COM, and an informed consent was obtained from all participants. The HRCT images were studied in comparison with the intraoperative findings. The parameters of comparison were tympanic membrane, middle ear structures, and the status of cholesteatoma.

Results:

A total of 39 patients were included in the analysis: 14 male and 25 female patients. The age range was 9 to 50 years. As a result of the comparison between HRCT findings and intraoperative observations, we found that incus erosion through computed tomography (CT) was the same as during surgical observation in 12 cases (30.8%). Malleus appeared eroded on CT in 1 case (2.6%); however, 5 cases were seen with that observation during operation (12.8%). Cholesteatoma was similarly seen in the CT scan and during surgery with a significant relation between intraoperative cholesteatoma extending and HRCT findings of the disease (95% confidence level, P-value = 0.001). The sensitivity, specificity, positive predictive value, and negative predictive value were 100% for detecting sigmoid plate erosion, dura exposure, incus erosion, stapes erosion, and malleus-incus joint discontinuity through preoperative CT.

Conclusions:

Intraoperative findings and HRCT have shown better results with good correlation of diagnostic value regarding the comparisons between recorded observations, especially in detecting sigmoidal plate erosion, dural exposure, incus and stapes erosion, and malleus-incus joint discontinuity. Preoperative CT scan is beneficial and contributory in the decision of indicating surgery to patients.
Size facilitates profitable ski lift operations
Authors: Falk Martin , Steiger Robert
Published: August 2019

The book profits of 220 ski lift operators in Austria are analysed in order to identify the determinants relevant for business success. The median ratio of accounting profits to total assets was zero in 2013, while 43% had negative ‘book’ profits and another 12% had zero profits. Results using quantile regressions show that the ratio of book profits to total assets depends significantly on total length of ski slopes (size), maximum altitude of ski lifts, presence of a neighbour close by, the availability of nearby accommodation and the share of foreign overnight stays. Size usually has the greatest effect, which is even more pronounced in the lower part of the conditional distribution of the book profit ratio. Since size is the most important driver of the profit ratio, it can be expected that the pressure on, so far, untapped high alpine terrain will increase in the future.
Mediatization of conflict in the social media era: A case study of Sino-Indian border crisis in 2017
Authors: Zhang Shixin Ivy
Published: August 2019

Inspired by the concepts of Arrested War and actor–network theory, this study has traced and analyzed four main actors in the wars and conflicts in the social media age: social media platform, the mainstream news organizations, online users, and social media content. These four human and nonhuman actors associate, interact, and negotiate with each other in the social media network surrounding specific issues. Based on the case study of Sino-Indian border crisis in 2017, the central argument is that social media is playing an enabling role in contemporary wars and conflicts. Both professional media outlets and web users employ the functionalities of social media platforms to set, counter-set, or expand the public agenda. Social media platform embodies a web of technological and human complexities with different actors, factors, interests, and relations. These actor-networks and the macro social-political context are influential in the mediatization of conflict in the social media era.
Numerical investigation into the fuel evaporation and mixture formation characteristics of a free-piston diesel engine
Authors: Yuan Chenheng , Han Cuijie , Yang Mian , Zhang Yan
Published: August 2019

The free-piston engine generator becomes a new-type potential substitute for the conventional crankshaft combustion engine. This article presents a simulation to study the fuel spray and mixing characteristics of a diesel free-piston engine generator by comparing a corresponding crankshaft combustion engine. A full-cycle model which couples with piston dynamics, combustion, and gas exchange is developed to simulate the fuel spray, atomization, and mixing in the free-piston engine generator. The result indicates that compared with the crankshaft combustion engine, the free-piston engine generator provides a higher temperature and pressure for fuel spray and mixing during the ignition delay, but its ignition delay lasts shorter. The free-piston engine generator shows a shorter spray penetration and more fuel impingement due to its smaller combustion chamber volume during the injection process. The free-piston engine generator exhibits a lower level of air utilization and worse uniformity of fuel–air mixture in combustion chamber. In addition, the shorter ignition delay of free-piston engine generator makes the time of atomization, evaporation, and mixing of fuel shorter, and the mixing effect of free-piston engine generator is worse, resulting in less combustible mixture formed during the ignition delay. In addition, some guiding suggestions have been proposed to improve the fuel spray and fuel–air mixing characteristics of free-piston engine generator.
Daylight: What makes the difference?
Authors: Knoop M , Stefani O , Bueno B , Matusiak B , Hobday R , Wirz-Justice A , Martiny K , Kantermann T , Aarts MPJ , Zemmouri N , Appelt S , Norton B
Published: August 2019

Light is necessary for vision; it enables us to sense and perceive our surroundings and in many direct and indirect ways, via eye and skin, affects our physiological and psychological health. The use of light in built environments has comfort, behavioural, economic and environmental consequences. Daylight has many particular benefits including excellent visual performance, permitting good eyesight, effective entrainment of the circadian system as well as a number of acute non-image forming effects and the important role of vitamin D production. Some human responses to daylight seem to be well defined whilst others require more research to be adequately understood. This paper presents an overview of current knowledge on how the characteristics of daylight play a role in fulfilling these and other functions often better than electric lighting as conventionally delivered.
An Investigation of Probationary At-Risk Freshmen’s Future-Oriented Motivation and Future-Oriented Self-Regulated Learning
Authors: Lee Jieun , Blankenship Benjamin B.
Published: August 2019

This study investigated at-risk freshmen’s future-oriented motivation (motivation for developing and pursuing academic future goals) and future-oriented self-regulated learning (commitment to utilizing self-regulatory strategies to achieve those goals) using the Persistent Academic Possible Selves Scale (PAPSS). Study goals were to validate the factor structure of the PAPSS and to assess the relationships between the PAPSS factors and important academic measures. Probationary at-risk freshmen due to low grade point averages (i.e., below 2.0) participated in an online survey at the end of the semester ( n = 226). The final factor model consists of three persistent goal factors (improving grades, better student, and more attention in class) and four theory-based factors (social identity, self-concept, motivational self-regulation, and performance). The factor structure and the relationships between the factors and other measures supported the PAPSS as an adequately valid measure for assessing at-risk college students’ future-oriented motivation and future-oriented self-regulated learning in educational settings.
Digital Media and the Changing Nature of Labor Action
Authors: Ullah Faiz
Published: August 2019

Precarious working conditions resulting from neoliberal policies of the Indian state have placed an overwhelmingly young and mobile industrial workforce under a lot of duress. Traditional forms of organizations and modes of resistance such as labor strikes that were thought to be effective are now increasingly seen as inadequate against the speed and complexity of contemporary production processes, forcing the workers to devise commensurate responses. In this article, I discuss some of the newer strategies of resistance gaining prominence among industrial workers, especially as they are mediated through digital media. Focusing on online self-work underpinning worker agitations, I argue that contemporary labor movement should devise creative strategies using new media tools, to which the millennial worker has unprecedented access, in addition to their traditional rank and file struggles, to counter contemporary challenges.
Safety of simultaneous bilateral carotid artery stenting for bilateral carotid artery stenosis
Authors: Oshita Jumpei , Sakamoto Shigeyuki , Okazaki Takahito , Ishii Daizo , Kurisu Kaoru
Published: August 2019

Background

Bilateral carotid artery stenting (BCAS) is often performed in two stages (staged BCAS) but it is also an option to be performed in one stage (simultaneous BCAS). To confirm the safety of simultaneous BCAS, we retrospectively analyzed perioperative and postoperative course of simultaneous BCAS compared with staged BCAS.

Materials and methods

Patients with symptomatic stenosis of ≥50% or asymptomatic stenosis of ≥80% of bilateral carotid arteries underwent BCAS. Procedure time, symptomatic ischemic complications, presence/absence of high-intensity spots on postoperative diffusion-weighted image, duration of postoperative hospital stays and 30 days outcome of patients performed with simultaneous BCAS (group A, 8 patients with 16 stenotic lesions (8 procedures)) were compared with those of staged BCAS (group B, 4 patients with 8 stenotic lesions (8 procedures)).

Results

In groups A and B, procedure time was 146.0 ± 53.8 and 103.5 ± 39.4 min; intraoperative hypotension was observed in 62.5% and 50.0%; postoperative hypotension occurred in 37.5% and 50.0%; diffusion-weighted image showed high-intensity spots in 37.5% and 12.5%; and duration of postoperative hospital stays was 5.1 ± 1.8 and 5.3 ± 2.3 days. No patients suffered symptomatic ischemic complications. In simultaneous BCAS, there was a tendency that procedure time was longer and high-intensity spots on postoperative diffusion-weighted image was more frequent, but there was no increase in symptomatic ischemic complications and duration of hospital stays compared to staged BCAS.

Conclusions

Safety of simultaneous BCAS may not be inferior to staged BCAS. In terms of duration of hospital stays, simultaneous BCAS can be superior to staged BCAS for patients with bilateral carotid artery stenosis.
Optimal delay time to initiate anticoagulation after ischemic stroke in atrial fibrillation (START): Methodology of a pragmatic, response-adaptive, prospective randomized clinical trial
Authors: King Benjamin T , Lawrence Patrick D , Milling Truman J , Warach Steven J
Published: August 2019

Rationale

An estimated 15% of all strokes are associated with untreated atrial fibrillation. Long-term secondary stroke prevention in atrial fibrillation is anticoagulation, increasingly with non-vitamin K oral anticoagulants. The optimal time to initiate anticoagulation following an atrial fibrillation-related stroke that balances hemorrhagic conversion with recurrent stroke is not yet known.

Aims

To determine if there is an optimal delay time to initiate anticoagulation after atrial fibrillation-related stroke that optimizes the composite outcome of hemorrhagic conversion and recurrent ischemic stroke.

Sample size estimates

The study will enroll 1500 total subjects split between a mild to moderate stroke cohort (1000) and a severe stroke cohort (500).

Methods and design

This study is a multi-center, prospective, randomized, pragmatic, adaptive trial that randomizes subjects to four arms of time to start of anticoagulation. The four arms for mild to moderate stroke are: Day 3, Day 6, Day 10, and Day 14. The time intervals for severe stroke are: Day 6, Day 10, Day 14, and Day 21. Allocation involves a response adaptive randomization via interim analyses to favor the arms that have a better risk–benefit profile.

Study outcomes

The primary outcome event is the composite occurrence of an ischemic or hemorrhagic event within 30 days of the index stroke. Secondary outcomes are also collected at 30 and 90 days.

Discussion

The optimal timing of direct oral anticoagulants post-ischemic stroke requires prospective randomized testing. A pragmatically designed trial with adaptive allocation and randomization to multiple time intervals such as the START trial is best suited to answer this question in order to directly inform current practice on this question.
The use of multiple externally directed attentional focus cues facilitates motor learning
Authors: Becker Kevin A , Fairbrother Jeffrey T
Published: August 2019

Attentional focus research consistently suggests that the use of an external focus of attention improves motor learning and performance relative to an internal focus. It appears, however, that external focus cues are not frequently adopted in applied sport settings. One issue that may contribute to this disparity relates to variability in how cues are employed in research and practice. Experimental research tends to use a single-cue approach, while in sports, athletes often sample several cues within the same practice. A limitation of the single-cue approach is that attentional focus effects could be due either to focus direction (internal vs. external) or to the relative effectiveness of a particular cue (e.g. an effective externally focused cue vs. an ineffective internally focused cue). This study tested whether external focus benefits generalize to situations in which participants use multiple cues of the same type throughout acquisition. Volunteers ( N = 22) learned a dart throwing task while using three internally or externally focused cues. Results indicated an external focus led to lower error scores during acquisition and a delayed retention test ( p’s < .05). These results demonstrate that the external focus benefit generalizes to situations where a performer uses multiple cues.
Investigating the functional grip strength of elderly fallers in Singapore
Authors: Mat Jais Ita Suzana , Nadkarni Nivedita Vikas , NG Yee Sien , Seow Dennis Chuen Chai , Wong Ting Hway
Published: August 2019

Background:

Static grip strength has been a reliable method for assessing the functional capacity of the individual and can be a useful marker for identifying elderly people at risk of functional deterioration leading to a fall. However, static grip strength alone may not represent the true maximum strength that an individual could exert in his/her daily life, especially if the task requires simultaneous forces from gripping and a forearm twisting action, which is termed as functional isometric grip strength. Hence, the objectives of this study were to determine the differences in the fallers’ grip strengths at static-neutral grip position and during isometric forearm pronation/supination, as well as the differences between the maximum and sustained isometric grip strengths.

Methods:

Data were analysed from 31 elderly people (11 males and 20 females) aged 70 and over. Using a custom-made hand strength measurement device, three measurements were taken: (1) grip strength in neutral forearm position; (2) grip strength during isometric forearm pronation; and (3) grip strength during isometric forearm supination.

Results:

Elderly fallers could only achieve approximately 60%–80% of the maximum normative strength. Additionally, it was found that their functional isometric grip strengths were generally weaker than their static maximal grip strength, especially during isometric supination as either maximum or sustained isometric supination grip strengths (Dominant hand: 10.6 kg and 8.5 kg, respectively (males); 6.0 kg and 4.4 kg, respectively (females)).

Conclusion:

Elderly fallers are weaker when their grip is subjected to additional torque, endurance or both. Hence, these findings have potential implications for designing better screening tools for the geriatric population.
Evaluating the use of machine learning in the assessment of joint angle using a single inertial sensor
Authors: Argent Rob , Drummond Sean , Remus Alexandria , O’Reilly Martin , Caulfield Brian
Published: August 2019

Introduction

Joint angle measurement is an important objective marker in rehabilitation. Inertial measurement units may provide an accurate and reliable method of joint angle assessment. The objective of this study was to assess whether a single sensor with the application of machine learning algorithms could accurately measure hip and knee joint angle, and investigate the effect of inertial measurement unit orientation algorithms and person-specific variables on accuracy.

Methods

Fourteen healthy participants completed eight rehabilitation exercises with kinematic data captured by a 3D motion capture system, used as the reference standard, and a wearable inertial measurement unit. Joint angle was calculated from the single inertial measurement unit using four machine learning models, and was compared to the reference standard to evaluate accuracy.

Results

Average root-mean-squared error for the best performing algorithms across all exercises was 4.81° (SD = 1.89). The use of an inertial measurement unit orientation algorithm as a pre-processing step improved accuracy; however, the addition of person-specific variables increased error with average RMSE 4.99° (SD = 1.83°).

Conclusions

Hip and knee joint angle can be measured with a good degree of accuracy from a single inertial measurement unit using machine learning. This offers the ability to monitor and record dynamic joint angle with a single sensor outside of the clinic.
The Mediating Role of Mathematics Teaching Efficacy on the Relationships Between Pedagogical Content Knowledge and Mathematics Teaching Anxiety
Authors: Aksu Zeki , Kul Ümit
Published: August 2019

Teaching efficacy, teaching anxiety, and teaching knowledge are crucial factors in effective teaching. This study investigated the mediating role of mathematics teaching efficacy (MTE) in the relationship between pedagogical content knowledge (PCK) and mathematics teaching anxiety (MTA) for pre-service mathematics teachers. The participants were 463 volunteer pre-service teachers who completed a questionnaire package that included the MTE Scale, the MTA Scale, and the PCK Scale. The theoretical model was tested using structural equation modeling and a bootstrapping procedure. It was revealed that MTE has a partial mediating role in the relationship between PCK and MTA for pre-service teachers. The findings indicated that a high level of PCK increases pre-service teachers’ MTE, which decreases their MTA. Although PCK predicts MTE that in turn predicts MTA, more longitudinal and experimental studies are needed to better understand this sequence.
Peek or Push: An Examination of Two Types of Room Clearing Tactics for Active Shooter Event Response
Authors: Blair J. Pete , Martaindale M. Hunter , Sandel William L.
Published: August 2019

Prior to the modern era of active shooter events, the standard training for patrol officers responding to an ongoing shooting event required the responding patrol officer(s) to contain the shooter in the building where the attack was occurring, control access to the location, attempt to communicate with the shooter, and call the Special Weapons and Tactics (SWAT) team. Recently, research has been undertaken to empirically examine different law enforcement response options. This article details one such experiment. The article details a tactic known as the peek. Utilizing an experimental design, we present findings regarding the peek room entry technique.
Spatial segregation and urban form in Mexican cities
Authors: Garnica-Monroy Ruben , Alvanides Seraphim
Published: August 2019

With a population of more than 120 million people, most Mexican cities suffer from socioeconomic inequalities and these are worsened by spatial inequalities resulting from their urban form and structure. A number of studies have been published looking at limited public services and how this may affect those on lower incomes in Mexico. However, very few studies have used spatial accessibility as a means of explaining urban inequalities and informing city planning. Spatial accessibility is defined as the measurable geographical access from residential locations to destinations for services and public goods. This paper investigates the potential of a spatial accessibility index to provide evidence for making location/planning decisions that benefit the largest number of residents. To achieve this aim, we combine three geographical secondary data sets with geospatial analysis. First, two important urban public services, i.e. health and education, are located, and catchment areas are then generated according to their respective sizes. For the second set, the integration values of each city at metropolitan and district scales are calculated using Space Syntax to observe how its configuration may influence the distribution of activities and the way the inhabitants live and move. The third set is demographic data from the 2010 national census of Population and Housing, analysed at the residential block level. This paper focuses on the results of combining two accessibility indices (cumulative opportunities and Space Syntax’s integration value) that examine the degree to which the lack of a basic public service could be associated with the spatial segregation of an area to provide evidence (comprehensible by decision-makers) for making location and planning decisions that benefit the largest number of residents.
Voice hoarseness in a patient with underlying Eisenmenger's syndrome: A case report
Authors: Suryavanshi Palak , Parameswaran Sreejit , Sharma Nishant , Murphy Russell A. , Sharma Anil R.
Published: August 2019

Background

The natural history of patients diagnosed with Eisenmenger's Syndrome typically revolve around the pediatric population. Medical advances have allowed these patients to live longer and present with a different subset of symptoms as a result of the progression of their disease process.

Case presentation

In this case report, we discuss a 77-year-old Caucasian female with Eisenmenger's Syndrome presenting with hoarseness. Clinical and imaging studies reveal a left vocal cord paralysis secondary to a progressively enlarging patent ductus arteriosus (PDA) and dilation of pulmonary arteries causing mass effect on the left recurrent laryngeal nerve.

Conclusion

From a clinical perspective, this case highlights the need for otolaryngologists to be aware of the pathophysiology of Eisenmenger's Syndrome as it progresses with age.
Removal of all time-varying sea-surface effects by source deghosting and demultiple
Authors: Cecconello Elsa , Asgedom Endrias G. , Söllner Walter
Published: August 2019

Seismic source deghosting and sea-surface-related demultiple have been long-standing problems in marine seismic data processing. Although the receiver ghost problem may be considered as solved by using collocated measurement of pressure and normal velocity wavefields, the source deghosting and demultiple algorithms are still limited by assumptions related to the sea-surface condition. We have investigated the impact of a time-varying rough sea surface on source deghosting and demultiple. Starting from Rayleigh’s reciprocity theorem for time-varying sea surfaces, we uncover a fundamental limitation for source deghosting of time-dependent wavefields, such as marine seismic data that contain a receiver ghost or sea-surface-related multiples. We use simple synthetic examples to study the impact of source deghosting on sea-surface-related multiples. To resolve this limitation, we derive a method for simultaneous source deghosting and sea-surface-related demultiple for time-variant wavefields. Finally, we use the complex geologic model Sigsbee 2B first to illustrate that the source deghosting operation brings significant errors when applied to a data set containing sea-surface multiples. Second, we find that this problem can be resolved by simultaneously performing source deghosting and demultiple operations even in the presence of time-varying sea surfaces.
Development and Testing of the CAHPS Cancer Care Survey
Authors: Evensen Christian T. , Yost Kathleen J. , Keller San , Arora Neeraj K. , Frentzel Elizabeth , Cowans Tamika , Garfinkel Steven A.
Published: August 2019

PURPOSE:

The Consumer Assessment of Healthcare Providers and Systems (CAHPS) Cancer Care Survey is a systematic assessment of health care experiences of patients with cancer. It supports comparisons among all cancer treatment settings and modalities.

METHODS:

Formative research included 16 focus groups with patients receiving treatment and family members; advice from a panel of oncology and quality improvement experts; and interviews with stakeholders representing oncology associations, accredited cancer centers, and community oncology practices. We conducted cognitive tests of the instrument and field tests at six cancer centers and four community oncology practices, after which the survey was finalized and obtained the CAHPS trademark.

RESULTS:

The survey includes 56 questions that form six core composite measures (Getting Timely Care; Supporting Patient Self-Management; Available to Provide Care and Information; Provider Communication; Care Coordination; and Courteous Office Staff); two single-item measures of family participation in care and interpreter services; and two global ratings of cancer care and the treatment team. Sixteen additional items form three supplemental composite measures: Shared Decision-Making, Keeping Patients Informed, and Access to Care.

CONCLUSION:

Mail-only, mail-telephone mixed-mode, and Web-mail mixed-mode data collection methods are recommended. The questionnaires and instructions for use are free and available in English and Spanish on the CAHPS Website ( www.ahrq.gov/cahps ).
Conformational adaptation of UNCG loops upon crowding
Authors: Meyer Mélanie , Walbott Hélène , Oliéric Vincent , Kondo Jiro , Costa Maria , Masquida Benoît
Published: August 2019

If the A-form helix is the major structural motif found in RNA, the loops that cap them constitute the second most important family of motifs. Among those, two are overrepresented, GNRA and UNCG tetraloops. Recent surveys of RNA structures deposited in the PDB show that GNRA and UNCG tetraloops can adopt tertiary folds that are very different from their canonical conformations, characterized by the presence of a U-turn of a Z-turn, respectively. Crystallographic data from both a lariat-capping (LC) ribozyme and a group II intron ribozyme reveal that a given UUCG tetraloop can adopt a distinct fold depending on its structural environment. Specifically, when the crystal packing applies relaxed constraints on the loop, the canonical Z-turn conformation is observed. In contrast, a highly packed environment induces “squashing” of the tetraloop by distorting its sugar-phosphate backbone in a specific way that expels the first and fourth nucleobases out of the loop, and falls in van der Waals distance of the last base pair of the helix, taking the place of the pair formed between the first and fourth residues in Z-turn loops. The biological relevance of our observations is supported by the presence of similarly deformed loops in the highly packed environment of the ribosome and in a complex between a dsRNA and a RNase III. The finding that Z-turn loops change conformation under higher molecular packing suggests that, in addition to their demonstrated role in stabilizing RNA folding, they may contribute to the three-dimensional structure of RNA by mediating tertiary interactions with distal residues.
Adhering to evidence-based clinical practice guidelines results in lower readmission rates in Brazilian private hospitals
Authors: Geiger Sebastian Naschold , Japiassu André Miguel , Filho Hugo Tannus Mendonça , Rose Alexandre Maximiliano , Coudry Daniel , Wilson Margareth-Mary
Published: August 2019

Background/Aims

In clinical practice, an evidence-based approach is viewed as a pathway to creating a sustainable healthcare system. As such, many leaders in private hospitals still regard evidence-based approaches as tools to curtail length of stay. This article aimed to evaluate the impact of evidence-based clinical practice guidelines on the quality of care in Brazilian private hospitals.

Methods

The adherence to evidence-based clinical practice was compared to hospital readmission rates through a linear regression model. A machine learning clustering algorithm was applied to classify the hospitals according to these measures.

Results

The linear regression model showed a reverse correlation between adherence to evidence based clinical practice and readmission rates. The algorithm distributed the 83 hospitals into two groups, following the same pattern, with an additional finding suggesting an optimal hospital size for quality measures.

Conclusions

This article suggests that an evidence-based approach is associated with higher quality of care, by showing that hospitals following evidence-based guidelines have lower readmission rates than those who do not.
The inverse eigenvalue problem for Leslie matrices
Authors: Benvenuti Luca
Published: August 2019

The Nonnegative Inverse Eigenvalue Problem (NIEP) is the problem of determining necessary and sufficient conditions for a list of $n$ complex numbers to be the spectrum of an entry--wise nonnegative matrix of dimension $n$. This is a very difficult and long standing problem and has been solved only for $n\leq 4$. In this paper, the NIEP for a particular class of nonnegative matrices, namely Leslie matrices, is considered. Leslie matrices are nonnegative matrices, with a special zero--pattern, arising in the Leslie model, one of the best known and widely used models to describe the growth of populations. The lists of nonzero complex numbers that are subsets of the spectra of Leslie matrices are fully characterized. Moreover, the minimal dimension of a Leslie matrix having a given list of three numbers among its spectrum is provided. This result is partially extended to the case of lists of $n > 2$ real numbers.