bluuebunny/crossref_metadata_2025 huggingface dataset:
Nonlinear generalized minimum variance control and control performance assessment of nonlinear systems based on a Wiener model
Authors: Kazemi Mahdi , Arefi Mohammad Mehdi
Published: February 2017

In this paper, a nonlinear generalized minimum variance (NGMV) controller based on a Wiener model is designed. The NGMV controller is used as a benchmark in control performance assessment to assess a class of nonlinear systems modelled by the proposed Wiener model, while a general linear disturbance is added in the output of the plant. It is shown that, to assess a nonlinear system, the routine input–output operating data and an estimated value of the intermediate signal in the Wiener model can be used to evaluate the performance of the current controller. The proposed methodology is simulated for two nonlinear plants with different nonlinear characteristics to show the effectiveness of the proposed approach.
Observer-based bumpless switching control for switched linear systems with sensor faults
Authors: Qi Yiwen , Hu Jiaming
Published: February 2017

This paper investigates the bumpless transfer problem of switched linear systems with sensor faults. The framework of the switched control systems includes two kinds of controllers, one is for normal use and the other is for fault-tolerant control when sensor faults have occurred. Considering that the information of the sensor faults is unknown to the controller, an observer is designed for the fault-tolerant controller. Moreover, in view of the issue that the output difference between the online and offline controllers may induce undesired oscillations in control input at the switching instant, a bumpless transfer compensator is presented based on sliding mode control. Due to the reasonably designed compensator, the difference can be minimized to a small value to guarantee smooth transitions of the control input when sensor faults have occurred. Finally, numerical simulations verify the effectiveness of the proposed method.
A prototype telerobotic platform for live transmission line maintenance: Review of design and development
Authors: Banthia Vikram , Maddahi Yaser , Zareinia Kourosh , Liao Stephen , Olson Tim , Fung Wai-Keung , Balakrishnan Subramaniam , Sepehri Nariman
Published: February 2017

This paper reports technical design of a novel experimental test facility, using haptic-enabled teleoperation of robotic manipulators, for live transmission line maintenance. The goal is to study and develop appropriate techniques in repair overhead power transmission lines by allowing linemen to wirelessly guide a remote manipulator, installed on a crane bucket, to execute dexterous maintenance tasks, such as twisting a tie wire around a cable. Challenges and solutions for developing such a system are outlined. The test facility consists of a PHANToM Desktop haptic device (master site), an industrial hydraulic manipulator (slave site) mounted atop a Stewart platform, and a wireless communication channel connecting the master and slave sites. The teleoperated system is tested under different force feedback schemes, while the base is excited and the communication channel is delayed and/or lossy to emulate realistic network behaviors. The force feedback schemes are: virtual fixture, augmentation force and augmented virtual fixture. Performance of each scheme is evaluated under three measures: task completion time, number of failed trials and displacement of the slave manipulator end-effector. The developed test rig has been shown to be successful in performing haptic-enabled teleoperation for live-line maintenance in a laboratory setting. The authors aim at establishing a benchmark test facility for objective evaluation of ideas and concepts in the teleoperation of live-line maintenance tasks.
Neural-network-based robust hybrid force/position controller for a constrained robot manipulator with uncertainties
Authors: Ghajar Mohammad-Hossein , Keshmiri Mehdi , Bahrami Javad
Published: February 2017

Here, an intelligent hybrid position/force controller is designed for a constrained robot manipulator with contact friction between its end-effector and environment in presence of both large parameter and dynamic uncertainties. The controller includes two major parts. The first part, denoted as the main controller, consists of two closed-loops fulfilling motion tracking and force tracking objectives. The second part, called the tuning controller, is an adaptive neural network controller to compensate for the deficiencies of the model-based controller. The stability of the overall system is guaranteed through the Lyapunov and passivity theorems. The performance of the controller is evaluated using numerical simulations as well as experimental implementation. In the experimental analyses, the proposed controller is implemented on a two-link robot manipulator that interacts with a vertical surface. Results show a significant decrease in tracking error in the presence of uncertainties, owing to use of neural network sub-block.
Looking Backward to Move Forward
Authors: Hameiri Boaz , Nadler Arie
Published: February 2017

Two large-scale surveys conducted in Israel (Study 1A) and the Palestinian Authority (Study 1B) show that the belief by group members that people in the “enemy” group acknowledge their victimhood (i.e., Holocaust and Nakba for Jews and Palestinians, respectively) is associated with Israeli-Jews’ readiness to accept responsibility for Palestinian sufferings and offer apologies. For Palestinians, this belief is linked to a perceived higher likelihood of a reconciled future with Israelis. Three field experiments demonstrate that a manipulated high level of acknowledgment of Jewish victimhood by Palestinians (Studies 2 and 4) and of Palestinian victimhood by Israeli-Jews (Study 3) caused greater readiness to make concessions for the sake of peace on divisive issues (e.g., Jerusalem, the 1967 borders, the right of return) and increased conciliatory attitudes. Additional analyses indicate the mediating role of increased trust and reduced emotional needs in these relationships.
An Interview with Elizabeth Grosz: Geopower, Inhumanism and the Biopolitical
Authors: Grosz Elizabeth , Yusoff Kathryn , Clark Nigel
Published: February 2017

This article is an interview with Elizabeth Grosz by Kathryn Yusoff and Nigel Clark. It primarily addresses Grosz’s approaches to ‘geopower’, and the discussion encompasses an exploration of her ideas on biopolitics, inhuman forces and material experimentation. Grosz describes geopower as a force that subtends the possibility of politics. The interview is accompanied by a brief contextualizing introduction examining the themes of geophilosophy and the inhumanities in Grosz’s work.
An Interview with Elizabeth Povinelli: Geontopower, Biopolitics and the Anthropocene
Authors: Povinelli Elizabeth A. , Coleman Mathew , Yusoff Kathryn
Published: February 2017

This article is an interview with Elizabeth Povinelli, by Mathew Coleman and Kathryn Yusoff. It addresses Povinelli’s approaches to ‘geontologies’ and ‘geontopower’, and the discussion encompasses an exploration of her ideas on biopolitics, her retheorization of power in the current conditions of late liberalism, and the situation of the inhuman within philosophical and anthropological economies. Povinelli describes a mode of power that she calls geontopower, which operates through the governance of Life and Nonlife. The interview is accompanied by a brief contextualizing introduction.
Leadership in start-ups
Authors: Zaech Simon , Baldegger Urs
Published: February 2017

This article explores the role of leadership in start-ups and outlines a model of when, why and how leadership behaviour of founder-CEOs influences start-up performance. The model has been tested using a sample of 102 start-ups and their founder-CEOs and includes feedback from 372 employees, rating their leadership behaviour of founder-CEOs. The results indicate that transformational leadership has a significant and positive effect on start-up performance. However, no significant, direct effects on start-up performance were found for transactional leadership or laissez-faire leadership. Furthermore, the size of the start-up has a significant, positive, moderating effect on the relationship between laissez-faire leadership and start-up performance, as well as a significant, positive, moderating effect on the relationship between the transactional leadership dimension, management by exception and start-up performance. Results indicate that for start-ups and their performance, leadership behaviour is as important as their context. Today, leadership is neglected by most entrepreneurs and is not considered a motivation for founding a business. The results show that founders should focus more on leadership behaviour.
Intentions to reenter venture creation: The effect of entrepreneurial experience and organizational climate
Authors: Hsu Dan K , Shinnar Rachel S , Powell Benjamin C , Coffey Betty S
Published: February 2017

We identify and examine an important but overlooked group of entrepreneurs – individuals who have started one or more business ventures in the past but are currently employed in established organizations. We label these individuals as ‘organizationally employed former entrepreneurs’ (OEFEs). Our goal is to provide insight into the factors affecting their serial entrepreneurship intentions, that is, their intentions to re-enter entrepreneurship by re-engaging in venture creation. Applying Schneider’s attraction-selection-attrition theory, we identify factors that are likely to affect serial entrepreneurship intentions of OEFEs: the length of their venture creation experience and the climate of their employing organizations. Using survey data from 196 OEFEs, we show that the length of OEFE venture creation experience is positively related to their serial entrepreneurial intentions and that this relationship is negatively moderated by the organizational structure and entrepreneurial orientation of the organization in which the OEFEs are employed.
Differentiation of ductal carcinoma in situ versus fibrocystic changes by magnetic resonance imaging: are there pathognomonic imaging features?
Authors: Dietzel Matthias , Kaiser Clemens G , Wenkel Evelyn , Clauser Paola , Uder Michael , Schulz-Wendtland Rüdiger , Baltzer Pascal AT
Published: February 2017

Background

In breast magnetic resonance imaging (MRI), the diagnosis of ductal carcinoma in situ (DCIS) remains controversial; the most challenging cause of false-positive DCIS diagnosis is fibrocystic changes (FC).

Purpose

To search for typical and pathognomonic patterns of DCIS and FC using a standard clinical MRI protocol.

Material and Methods

Consecutive patients scheduled for breast MRI (standardized protocols @ 1.5T: dynamic-T1-GRE before/after Gd-DTPA [0.1 mmol/kg body weight (BW)]; T1-TSE), with subsequent pathological sampling, were investigated. Sixteen MRI descriptors were prospectively assessed by two experienced radiologists in consensus (blinded to pathology) and explored in patients with DCIS (n = 77) or FC (n = 219). Univariate and multivariate statistics were performed to identify the accuracy of descriptors (alone, combined). Furthermore, pathognomonic descriptor-combinations with an accuracy of 100% were explored (χ2 statistics; decision trees).

Results

Six breast MRI descriptors significantly differentiated DCIS from FC ( Pcorrected < 0.05; odds ratio < 7.9). Pathognomonic imaging features were present in 33.8% (n = 100) of all cases allowing the identification of 42.9% of FC (n = 94).

Conclusion

Pathognomonic patterns of DCIS and FC were frequently observed in a standard clinical MRI protocol. Such imaging patterns could decrease the false-positive rate of breast MRI and hence might help to decrease the number of unnecessary biopsies in this clinically challenging subgroup.
Effect of a low-frequency pulsed electromagnetic field on expression and secretion of IL-1β and TNF-α in nucleus pulposus cells
Authors: Zou Jun , Chen Yufeng , Qian Jiale , Yang Huilin
Published: February 2017

Objective

To investigate changes in nucleus pulposus cell expression and secretion of interleukin (IL)-1β and tumour necrosis factor (TNF)-α following stimulation with a low-frequency (LF) pulsed electromagnetic field (PEMF).

Methods

Primary rat nucleus pulposus cells were isolated and cultured in vitro, followed by stimulation with LF-PEMFs at a frequency of 2 Hz and different intensities, ranging from 0.5–3.0 A/m. Cells were observed for morphological changes, and proliferation rates were measured by cell viability counts. Expression of IL-1β and TNF-α within the nucleus pulposus cells was measured using western blotting, and levels of IL-1β and TNF-α secreted in the culture media were measured using enzyme-linked immunosorbent assay.

Results

Stimulation of nucleus pulposus cells with LF-PEMFs did not appear to affect cell morphology or nucleus pulposus cell IL-1β and TNF-α expression levels. LF-PEMFs did not significantly affect cell proliferation, however, levels of IL-1β and TNF-α secreted into the culture media were found to be significantly reduced in an intensity-dependent manner.

Conclusion

Low-frequency PEMF stimulation may inhibit secretion of IL-1β and TNF-α in cultured nucleus pulposus cells.
Association between patency of the circle of Willis and diabetes mellitus in patients with cerebral ischaemic stroke
Authors: Chi Ying , Lu Zu-neng
Published: February 2017

Objective

To examine patency of the cerebral anterior and posterior communicating arteries in patients with ischaemic stroke with or without diabetes mellitus.

Methods

This retrospective study included patients with acute ischaemic stroke treated between July 2011 and May 2016. Cerebral infarction was evaluated by magnetic resonance imaging. Anterior and posterior communicating-artery patency was determined using magnetic resonance angiography. Vessels were defined as patent or occluded.

Results

Out of 1 406 patients, incidence of vertebral basilar artery brain infarction and posterior cerebral artery brain infarction were significantly higher in patients with diabetes versus those without diabetes (35.5% versus 22.3% and 11.7% versus 6.8%, respectively). Among patients with posterior cerebral artery brain infarction, anterior and posterior communicating-artery patency rates were higher in patients with diabetes versus those without diabetes (66.7 versus 23.5% and 33.3% versus 5.9% [bilateral], respectively). Among patients with vertebral basilar artery infarction and posterior cerebral artery P1 segment infarction, patency rate of the anterior communicating artery was higher in patients with diabetes versus those without diabetes (55.7% versus 45.9%).

Conclusion

Among patients with ischaemic stroke, patency rate of the circle of Willis may be higher in patients with diabetes than those without diabetes.
Rosai-Dorfman disease of the subdural spine with a long segment lesion: A case report and literature review
Authors: Tu Ji , Li Wen-Tian , Yang Cao
Published: February 2017

Rosai-Dorfman disease (RDD) or sinus histiocytosis with massive lymphadenopathy is a rare benign disorder usually characterized by massive painless cervical lymphadenopathy and systemic manifestations. Extranodal involvement, especially spinal involvement, is extremely rare. We report a 41-year-old man who presented with only intermittent dorsodynia. His condition was diagnosed as non-specific inflammatory disease on the basis of preoperative puncture biopsy results. We performed total surgical resection. Histopathological findings showed distinctive emperipolesis and immunohistochemistry results were positive for cluster of differentiation CD68 and S100 and negative for CD1a. A good prognosis was confirmed at the 3-month follow-up visit. This is the first case of RDD of the subdural spine with such a long segment lesion. There is still no consensus regarding appropriate therapy for this type of RDD and the preoperative diagnosis remains challenging. The unusual presentation of our case serves as a reference when diagnosing and treating RDD.
Music, ballet, mindfulness, and psychological inflexibility
Authors: Serrano Telmo , Espírito-Santo Helena Amaral
Published: February 2017

Both music and dance training can be conceptualised as mindfulness-like practices due to their focus on the present moment. Mindfulness and music are associated with mental health. However, evidence from dance practice, especially among ballet students, shows an association with mental health problems. Psychological inflexibility involves cognitive fusion, which is an excessive involvement with internal events, leading to experiential avoidance. Since studies analysing these concepts are scarce in music and dance practice, we intended to examine their effects in young music and ballet students. This study involved 113 participants (9 to 16 years old), 64.4% girls, 34.5% with musical training, 29.2% with ballet training, and 36.3% with no training. All participants completed the Child and Adolescent Mindfulness Measure (CAMM) and the Avoidance and Fusion Questionnaire for Youth (AFQ-Y). AFQ-Y scores correlated with months of ballet training. Ballet students had greater psychological inflexibility than music students and students without any training. CAMM scores did not correlate with months of any practice, and did not distinguish between groups of practitioners. These data confirm prior findings that practice of ballet can have a potential impact on mental health by showing that young ballet students exhibit greater psychological inflexibility.
An Exploratory Study of the Effects of Work Environment Variables on Job Satisfaction Among Chinese Prison Staff
Authors: Jiang Shanhe , Lambert Eric G. , Liu Jianhong , Zhang Jinwu
Published: February 2017

Job satisfaction has been linked to many positive outcomes, such as greater work performance, increased organizational commitment, reduced job burnout, decreased absenteeism, and lower turnover intent/turnover. A substantial body of research has examined how work environment variables are linked to job satisfaction among U.S. correctional staff; far less research has examined prison staff in non-Western nations, especially China. Using survey data collected from two prisons in Guangzhou, China, this study investigated the level of job satisfaction among prison staff and how personal characteristics (i.e., gender, tenure, age, and educational level) and work environment variables (i.e., perceived dangerousness of the job, job variety, supervision, instrumental communication, and input into decision making) affect job satisfaction. The findings from ordinary least squares regression equations indicated that the work environment variables explained a greater proportion of the variance in the job satisfaction measure than the personal characteristics. In the full multivariate regression model, gender was the only personal characteristic to have a significant association with job satisfaction, with female staff reporting higher satisfaction. Input into decision making and job variety had significant positive associations, whereas dangerousness had a significant negative relationship with job satisfaction.
Assessment of unilateral neglect in stroke: Simplification and structuring of test items
Authors: Donoso Brown Elena V , Powell Janet M
Published: February 2017

Statement of context

Unilateral neglect is a complex impairment that is common after stroke and limits occupational performance. Sensitive assessment of unilateral neglect is critical for planning treatment and ensuring safe community discharge.

Critical reflection on practice

This reflection describes unexpected findings in the assessment of neglect with two individuals in the acute phase of recovery post-stroke. When trialing a new activity-based test battery, we observed few neglect behaviors during test tasks despite observation of multiple neglect behaviors outside of the testing situation. Upon reflection, we better understood how simplification and structuring of test items and environments could impact the observation and assessment of neglect behaviors.

Implications for practice

This practice analysis further supports the use of multiple assessments when evaluating unilateral neglect and specifically encourages the inclusion of assessment methods that maintain the complexity of everyday tasks and environments.
Self-organization of meaning and the reflexive communication of information
Authors: Leydesdorff Loet , Petersen Alexander M. , Ivanova Inga
Published: February 2017

Following a suggestion from Warren Weaver, we extend the Shannon model of communication piecemeal into a complex systems model in which communication is differentiated both vertically and horizontally. This model enables us to bridge the divide between Niklas Luhmann’s theory of the self-organization of meaning in communications and empirical research using information theory. First, we distinguish between communication relations and correlations among patterns of relations. The correlations span a vector space in which relations are positioned and can be provided with meaning. Second, positions provide reflexive perspectives. Whereas the different meanings are integrated locally, each instantiation opens global perspectives – ‘horizons of meaning’ – along eigenvectors of the communication matrix. These next-order codifications of meaning can be expected to generate redundancies when interacting in instantiations. Increases in redundancy indicate new options and can be measured as local reduction of prevailing uncertainty (in bits). The systemic generation of new options can be considered as a hallmark of the knowledge-based economy.
Mechanical and viscoelastic properties of epoxy nanocomposites reinforced with carbon nanotubes, nanoclay, and binary nanoparticles
Authors: Hosur Mahesh , Mahdi Tanjheel H , Islam Mohammad E , Jeelani S
Published: February 2017

Mechanical and viscoelastic properties of polymer nanocomposites reinforced with carboxyl functionalized multiwalled carbon nanotubes (COOH-MWCNT), montmorillonite nanoclays (MMT), and MWCNT/MMT binary nanoparticle were investigated. In this study, 0.3 wt% of COOH-MWCNT, 2 wt% of MMT, and 0.1 wt% COOH-MWCNT/2 wt% MMT binary nanoparticles by weight of epoxy were incorporated to modify SC-15 epoxy resin system. Nanocomposites were subjected to flexural test, dynamic mechanical, and thermomechanical analyses. Morphological study was conducted with microscopy. Addition of each of the nanoparticles in epoxy showed significant improvement in the mechanical and viscoelastic properties compared to those of the control ones. However, best results were obtained by addition of 0.1% MWCNT/2% MMT binary nanoparticles in epoxy. Nanocomposites modified with binary nanoparticles exhibited about 20% increase in storage modulus as well as 25℃ increase in the glass transition temperature. Flexural modulus for binary nanoparticle modified composites depicted about 30% improvement compared to the control ones. Thus, improvement of mechanical and viscoelastic properties was achieved by incorporating binary nanoparticles to epoxy nanocomposites. The increase in properties was attributed to the synergistic effect of MWCNTs and nanoclay in chemically interacting with each other and epoxy resin as well as in arresting and delaying the crack growth, once initiated.
Controlling bacterial fouling with polyurethane/N-halamine semi-interpenetrating polymer networks
Authors: Xiu Kemao , Wen Jianchuan , Porteous Nuala , Sun Yuyu
Published: February 2017

N-halamine-based interpenetrating polymer networks were developed as a simple and effective strategy in the preparation of antimicrobial polymers. An N-halamine monomer, N-chloro-2, 2, 6, 6-tetramethyl-4-piperidyl methacrylate, was incorporated into polyurethane in the presence of a cross-linker and an initiator. Post-polymerization of the monomers led to the formation of polyurethane/ N-halamine semi-interpenetrating polymer networks. The presence of N-halamines in the semi-interpenetrating polymer networks was confirmed by attenuated total reflectance infrared, water contact angle, and energy-dispersive X-ray spectroscopy analysis. The N-halamine contents in the semi-interpenetrating polymer networks could be readily controlled by changing reaction conditions. The distribution of active chlorines within the semi-interpenetrating polymer networks was characterized with energy-dispersive X-ray spectroscopy. Contact mode antimicrobial tests, zone of inhibition studies, and scanning electron microscopy observations showed that the semi-interpenetrating polymer networks had potent antimicrobial and antifouling effects against both Gram-positive and Gram-negative bacteria. Release tests demonstrated the outstanding stability of the N-halamine structures in the new semi-interpenetrating polymer networks.
Ontology, ‘hauntology’ and the ‘turn’ that keeps anthropology turning
Authors: Argyrou Vassos
Published: February 2017

Twentieth-century anthropology has been operating with the assumption of one nature and many cultures, one reality experienced and lived in many different ways. Its primary job, therefore, has been to render the otherness of the other understandable, to demonstrate that although different it is also the same; in short, to show that although other, others are people like us. The latest theoretical paradigm, known as the ‘ontological turn’, appears to reverse this assumption and to posit many natures and one culture. Whether it does in fact reverse it and constitutes a meta-ontology, as critics have pointed out, or it is only a heuristic, methodological device, as some of the proponents of the ‘turn’ have recently argued, the contention of my article is the same: first, this move – the ontological – is made in the hope of doing a better job in redeeming otherness than earlier anthropological paradigms; second, it fails as they did – in the same way and for the same reasons.
Relational psychoanalysis and anomalous communication
Authors: Wooffitt Robin
Published: February 2017

There has been consistent interest in telepathy within psychoanalysis from its start. Relational psychoanalysis, which is a relatively new development in psychoanalytic theory and practice, seems more receptive to experiences between patient and analyst that suggest ostensibly anomalous communicative capacities. To establish this openness to telepathic phenomena with relational approaches, a selection of papers recently published in leading academic journals in relational psychoanalysis is examined. This demonstrates the extent to which telepathy-like experiences are openly presented and seriously considered in the relational community. The article then discusses those characteristics of the relational approach that may facilitate greater openness to telepathic experience. The argument is that relational psychoanalysis provides a coherent framework in which otherwise anomalous phenomena of patient–analyst interaction can be understood.
Failure analysis of ceramic tool in intermittent turning of hardened steel
Authors: Ni Xiuying , Zhao Jun , Wang Fuzeng , Gong Feng , Zhong Xin , Tao Haiwang
Published: February 2017

The aim of this investigation is to identify the Al2O3-(W, Ti)C ceramic fracture modes and failure mechanisms under different cutting speeds and feed rates during intermittent turning of hardened 20CrMnTi steel. The failure surfaces of the cutting tools were examined by digital optical microscope and scanning electron microscope. The cutting forces and transient temperature in the intermittent turning process were measured during the entire life cycle. The experimental results showed that the cutting forces exhibited an increasing trend with the tool failure progression, which in turn accelerated the tool failure progression. The main failure modes of ceramic tools were wear and micro-chipping in the initial stage and final fractures, resulting from mechanical damage and thermal damage in intermittent turning processes. And the cutting temperature increased with the increase in cutting speed. The cutting speeds and feed rates were closely correlated with ceramic tool fracture modes and failure mechanisms. Furthermore, the combination of cutting parameters was divided into four regions with different fracture modes and failure mechanisms of cutting tools according to the fracture morphology of cutting tools. This partitioning analysis can provide a basis for the design and development of different ceramic cutting tools with the desired properties for different applications.
Rotor-state feedback control design to improve helicopter turbulence alleviation in hover
Authors: Ji Honglei , Chen Renliang , Li Pan
Published: February 2017

A helicopter flight control system with rotor-state feedback to improve turbulence alleviation in hover is presented. First, a flight dynamic model coupled with turbulence model is developed and validated. Then, an integrated control strategy with a rotor-state feedback control law is proposed based on the baseline control system. The feedback gains of body and rotor states are designed in synergy to improve turbulence alleviation in the interested frequency range of handling qualities. Subsequently, the effects of the rotor-state feedback gains on both the stability of rotor dynamics and helicopter turbulence alleviation are analyzed in detail. Finally, the effectiveness of the integrated control system is evaluated with linear analysis in frequency domain and nonlinear simulation in time domain. The results indicate that with the rotor-state feedback control law integrated into the control system, the helicopter turbulence alleviation in the interested frequency range is improved with less degradation in helicopter stability margins, and the roll and pitch rate responses of helicopter to turbulence, measured with Root-Mean-Square (RMS) values, are reduced by more than 50% and 35% respectively.
Unsteady vortical flow simulation in a Francis turbine with special emphasis on vortex rope behavior and pressure fluctuation alleviation
Authors: Luo Xianwu , Yu An , Ji Bin , Wu Yulin , Tsujimoto Yoshinobu
Published: February 2017

Hydro turbines operating at partial flow conditions usually have vortex ropes in the draft tube that generate large pressure fluctuations. This unsteady flow phenomenon is harmful to the safe operation of hydropower stations. This paper presents numerical simulations of the internal flow in the draft tube of a Francis turbine with particular emphasis on understanding the unsteady characteristics of the vortex rope structure and the underlying mechanisms for the interactions between the air and the vortices. The pressure fluctuations induced by the vortex rope are alleviated by air admission from the main shaft center, with the water-air two phase flow in the entire flow passage of a model turbine simulated based on the homogeneous flow assumption. The results show that aeration with suitable air flow rate can alleviate the pressure fluctuations in the draft tube, and the mechanism improving the flow stability in the draft tube is due to the change of vortex rope structure and distribution by aeration, i.e. a helical vortex rope at a small aeration volume while a cylindrical vortex rope with a large amount of aeration. The preferable vortex rope distribution can suppress the swirl at the smaller flow rates, and is helpful to alleviate the pressure fluctuation in the draft tube. The analysis based on the vorticity transport equation indicates that the vortex has strong stretching and dilation in the vortex rope evolution. The baroclinic torque term does not play a major role in the vortex evolution most of the time, but will much increase for some specific aeration volumes. The present study also depicts that vortex rope is mainly associated with a pair of spiral vortex stretching and dilation sources, and its swirling flow is alleviated little by the baroclinic torque term, whose effect region is only near the draft tube inlet.
Concomitant effect of low dose of lindane and intranasal lipopolysaccharide on respiratory system of mice
Authors: Tewari A , Sethi RS , Banga HS , Singh B , Gill JPS
Published: February 2017

Lindane is very commonly used organochlorine pesticide and has been reported to cause several toxic effects including respiratory insufficiency. However, effects of low concentration of lindane alone or in combination with microbial molecules on lungs are not fully understood. To understand the effects a preliminary study was designed on Swiss albino mouse. Male mice were divided into treatment and control group (20; each). Treatment mice were given lindane in ground nut oil orally at 0.25 mg kg−1 day−1 for 60 days. After treatment, 10 mice were challenged with intranasal Escherichia coli lipopolysaccharide (LPS; 80 μg per mice) and remaining 10 with normal saline. The mice were euthanized 16 h post-LPS exposure. Control mice (10 each) were given normal saline or the LPS alone. Mice exposed with lindane and in combination with LPS had increase in total cell counts and leukocyte counts in broncho-alveolar lavage. Histological examination showed lung injury in the lindane-treated mice. The histopathological changes were more pronounced in lindane along with LPS-exposed mice. Lindane alone and in combination with LPS showed expression of immunopositive Toll-like receptor (TLR)-4 and tumour necrosis factor-alpha (TNF-α) positive reaction in various cells of lungs. While LPS induced acute inflammation in the lungs, combination of lindane and LPS exacerbated histological signs of the inflammation. The data indicate that lindane alone or in combination with LPS caused changes in lung morphology and altered TLR-4 and TNF-α expression which may have led to altered response to LPS challenge.
Effects of piroxicam on tissue distribution of sulfadimidine in West African Dwarf male and female goats
Authors: Akogwu EI , Saganuwan SA , Onyeyili PA
Published: February 2017

Cases of Stevens–Johnson syndrome have been increasingly reported in Nigeria by individuals who consumed meat products of animals especially goats injected sulfonamides. Hence, tissue distribution and residues of intramuscular sulfadimidine were studied in West African Dwarf (WAD) goats. Twenty goats divided into two groups of 10 each (five males; five females) weighing 10.4 ± 1.63 kg were administered intramuscular sulfadimidine (100 mg/kg body weight), and the second group was coadministered 5 mg/kg of piroxicam via right and left thigh muscle, respectively. Samples of the liver, kidney, spleen, heart, lung, intestine, brain, and skeletal muscle were collected into sterile cellophane bags. Two untreated goats were killed and used for preparation of tissue standards. The tissue samples were stored frozen for analysis. High concentration of sulfadimidine residues was found in all the tissues of goats administered sulfadimidine as well as tissues of goats coadministered sulfadimidine/piroxicam for up to 30 days postdrug administration. Generally, residues of sulfadimidine were observed to be significantly higher than the acceptable limit (0.1 ppm). Hence, consumption of meats from WAD goats administered sulfadimidine may pose very high risk of Stevens–Johnson syndrome in sensitive humans. As such consumption of such meats should be avoided.
Pregnancy failure in patients with obstetric antiphospholipid syndrome with conventional treatment: the influence of a triple positive antibody profile
Authors: Latino J O , Udry S , Aranda F M , Perés Wingeyer S D A , Fernández Romero D S , de Larrañaga G F
Published: February 2017

Conventional treatment of obstetric antiphospholipid syndrome fails in approximately 20–30% of pregnant women without any clearly identified risk factor. It is important to identify risk factors that are associated with these treatment failures. This study aimed to assess the impact of risk factors on pregnancy outcomes in women with obstetric antiphospholipid syndrome treated with conventional treatment. We carefully retrospectively selected 106 pregnancies in women with obstetric antiphospholipid syndrome treated with heparin + aspirin. Pregnancy outcomes were evaluated according to the following associated risk factors: triple positivity profile, double positivity profile, single positivity profile, history of thrombosis, autoimmune disease, more than four pregnancy losses, and high titers of anticardiolipin antibodies and/or anti-βeta-2-glycoprotein-I (aβ2GPI) antibodies. To establish the association between pregnancy outcomes and risk factors, a single binary logistic regressions analysis was performed. Risk factors associated with pregnancy loss with conventional treatment were: the presence of triple positivity (OR = 5.0, CI = 1.4–16.9, p = 0.01), high titers of aβ2GPI (OR = 4.4, CI = 1.2–16.1, p = 0.023) and a history of more than four pregnancy losses (OR = 3.5, CI = 1.2–10.0, p = 0.018). The presence of triple positivity was an independent risk factor associated with gestational complications (OR = 4.1, CI = 1.2–13.9, p = 0.02). Our findings reinforce the idea that triple positivity is a categorical risk factor for poor response to conventional treatment.
No Time Like the Present
Authors: Hamaker Ellen L. , Wichers Marieke
Published: February 2017

There has been a strong increase in the number of studies based on intensive longitudinal data, such as those obtained with experience sampling and daily diaries. These data contain a wealth of information regarding the dynamics of processes as they unfold within individuals over time. In this article, we discuss how combining intensive longitudinal data with either time-series analysis, which consists of modeling the temporal dependencies in the data for a single individual, or dynamic multilevel modeling, which consists of using a time-series model at Level 1 to describe the within-person process while allowing for individual differences in the parameters of these processes at Level 2, has led to new insights in clinical psychology. In addition, we discuss several methodological and statistical challenges that researchers face when they are interested in studying the dynamics of psychological processes using intensive longitudinal data.
The Math Anxiety-Performance Link
Authors: Foley Alana E. , Herts Julianne B. , Borgonovi Francesca , Guerriero Sonia , Levine Susan C. , Beilock Sian L.
Published: February 2017

Demand for science, technology, engineering, and mathematics (STEM) professionals is on the rise worldwide. To effectively meet this demand, many governments and private organizations have revamped STEM education and promoted training to enhance math and science skills among students and workers. Education and training programs typically focus on increasing individuals’ math and science knowledge. However, data from laboratory studies and large-scale international assessments suggest that fear or apprehension about math, math anxiety, should also be considered when trying to increase math achievement and, in turn, STEM career success. This article reviews findings that shed light on antecedents of math anxiety, the bidirectional math anxiety-performance relation, underlying mechanisms, and promising routes to mitigating the negative relation between math anxiety and math performance.
Birth of a New Perspective? A Call for Biopsychosocial Research on Childbirth
Authors: Saxbe Darby E.
Published: February 2017

Childbirth is a major life event with implications for family health, but it has been understudied by psychological scientists. The biopsychosocial model, which posits that health is shaped by biological, social, psychological, and cultural processes, can describe birth. The physiology of birth involves the interplay of hormones such as cortisol and oxytocin that are known to be affected by socioemotional factors. Existing theories on pain, stress, and social support can be applied to birth. Psychologists can adapt and incorporate empirically supported treatments, such as cognitive-behavioral therapy and mindfulness-based stress reduction, into childbirth education. Although father presence at birth represents a relatively new phenomenon, research on partner support has been lacking. Birth experiences may mediate associations between prenatal stress and postpartum adjustment, suggesting a need for more integrated, longitudinal research on birth.
Competitors or Teammates
Authors: Abrams Lise , Davis Danielle K.
Published: February 2017

Research has documented that proper names are more difficult to learn and remember than other types of words. Various causes of this difficulty have been proposed to better understand how proper names are represented in memory and the degree to which names compete with each other. In the retrieval of names, some studies show competition, whereas other studies find facilitation. During comprehension, names demonstrate competition by causing a Moses illusion: People erroneously answer invalid questions such as “How many animals did Moses take on the ark?”, failing to detect that Noah is the correct name for the question. Errors in both name retrieval and comprehension are more likely when the correct name and distractor name sound similar, share biographical characteristics, or have some visual resemblance. However, shared visual information has played a competitive role more consistently in name comprehension than retrieval, an asymmetry that remains to be investigated.
Age Equality after the Employment Directive
Authors: Meenan Helen
Published: February 2017

This article examines the Employment Directive from the age perspective and endorses a life course approach to ageing. It explores the permitted exclusions on grounds of age and especially the exceptional justification for direct age discrimination, contained in Article 6. In the end, EU Member States may find it more difficult to successfully transpose Article 6 than they imagine. The article reveals special challenges for age and refers to age laws in Ireland and the USA, in particular. It also refers to preparations for transposition in a number of Member States, including the United Kingdom and the Netherlands. Whether and to what extent age will ultimately receive the least protection of all the new grounds, remains to be seen and will depend largely on the individual approaches of the Member States. The ultimate consequence of the additional opportunities for excluding or justifying age discrimination may well be different protected areas throughout the EU.
Legal Reasoning and Legal Integration
Authors: Hage Jaap
Published: February 2017

According to Legrand, harmonization of European private law by means of a European Civil Code would not work, because of the different legal cultures (mentalités) within which such a code would have to operate. In the civil law tradition, legal reasoning on the basis of such a code would be deductive in the sense of the application of rules that are posited prior to the cases to which they should be applied. In the common law tradition, the starting point of legal reasoning is in the cases themselves. As a consequence, common law reasoning would abstract less from the peculiarities of individual cases.

The main point of this paper is that Legrand's picture of civil law reasoning is based on the subsumption model of rule application, which does not allow adaptation of the law to the needs of concrete cases other than through the limited possibilities of interpretation. It is argued that this picture is wrong. As an alternative, the reason-based model of rule application is proposed, which allows legal decision makers much more leeway to tailor the law to the needs of concrete cases. In a comparison with case-based reasoning it is argued that rule-based reasoning, according to the reason-based model, gives the decision maker the same leeway.

The final conclusion is that possible differences in legal culture between the civil law and the common law tradition are not rooted in the distinction between rule-based reasoning and case-based reasoning, and are therefore merely contingent. There is no reason why the introduction of a European Civil Code could not overcome the differences between the two traditions. Whether this would be desirable is a different question.
Traffic Accident Compensation in Belgium: An Example for Europe?
Authors: van Schoubroeck Caroline
Published: February 2017

On June 10, 2002 the European Commission adopted a proposal for a new Motor Insurance Directive. One of the goals of this proposal is to ensure that pedestrians and cyclists are covered by the compulsory insurance of the vehicle involved in the accident. Examples of legislation which has already sought to do so includes the French law (Loi Badinter in France) and Swedish law. It may be less well-known that Article 29bis of the Belgian Act of 21 November 1989 on the insurance against civil liability regarding the use of motor vehicles is another example of national legislation providing such coverage, not only of pedestrians and cyclists but also of motor vehicle passengers themselves. Belgian law provides a specific compensation for bodily injury and death incurred by every victim of a traffic accident involving a motor vehicle, with the exception of the driver. This is so regardless of whether the driver or the victim is at fault or not. This paper gives a brief overview of the key features of this compensation regime and its subsequent statutory changes and places it within the context of the case law.
Talking with the ‘pouvoir constituant’ in Times of Constitutional Reform: The European Court of Justice on Private Applicants' Access to Justice
Authors: Hanf Dominik
Published: February 2017

This contribution analyzes a classic theme of the Court's case law: the relationship between judges and pouvoir constituant. This relationship has traditionally been marked by the ECJ's role as the driving force in the ‘constitutionalization’ of the EC Treaties – which has, to a large extent, been accepted and even codified by the Member States in subsequent treaty revisions. However, the ECJ appears to be now more reluctant to act as a ‘law-maker.’ In this context, the recent judgment in Unión de Pequeños Agricultores (UPA) – an important decision by which the ECJ refused to liberalize individuals' access to the Community Courts – is examined. It appears from this analysis that the ECJ's UPA judgment indicates the beginning of a new phase in the ‘constitutional dialogue’ between the ECJ and the ‘Masters of the Treaties.’