bluuebunny/crossref_metadata_2025 huggingface dataset:
Mobile health messaging service and helpdesk for South African mothers (MomConnect): history, successes and challenges
Authors: Barron Peter , Peter Joanne , LeFevre Amnesty E , Sebidi Jane , Bekker Marcha , Allen Robert , Parsons Annie Neo , Benjamin Peter , Pillay Yogan
Published: April 2018

MomConnect is a flagship programme of the South African National Department of Health that has reached over 1.5 million pregnant women. Using mobile technology, MomConnect provides pregnant and postpartum women with twice-weekly health information text messages as well as access to a helpdesk for patient queries and feedback. In just 3 years, MomConnect has been taken to scale to reach over 95% of public health facilities and has reached 63% of all pregnant women attending their first antenatal appointment. The helpdesk has received over 300 000 queries at an average of 250 per day from 6% of MomConnect users. The service is entirely free to its users. The rapid deployment of MomConnect has been facilitated by strong government leadership, and an ecosystem of mobile health implementers who had experience of much of the content and technology required. An early decision to design MomConnect for universal coverage has required the use of text-based technologies (short messaging service and Unstructured Supplementary Service Data) that are accessible via even the most basic mobile phones, but cumbersome to use and costly at scale. Unlike previous mobile messaging services in South Africa, MomConnect collects the user’s identification number and facility code during registration, enabling future linkages with other health and population databases and geolocated feedback. MomConnect has catalysed additional efforts to strengthen South Africa’s digital health architecture. The rapid growth in smartphone penetration presents new opportunities to reduce costs, increase real-time data collection and expand the reach and scope of MomConnect to serve health workers and other patient groups.
User assessments and the use of information from MomConnect, a mobile phone text-based information service, by pregnant women and new mothers in South Africa
Authors: Skinner Donald , Delobelle Peter , Pappin Michele , Pieterse Desiree , Esterhuizen Tonya Marianne , Barron Peter , Dudley Lilian
Published: April 2018

MomConnect was designed to provide crucial health information to mothers during pregnancy and in the early years of child rearing in South Africa. The design drew on the success of the Mobile Alliance for Maternal Action’s programme in South Africa, as well as a growing list of mobile health (mHealth) interventions implemented internationally. Services such as MomConnect are dependent on user acceptability as all engagements are voluntary, meaning that tools have to be easy to use and useful to be successful. This paper describes the evaluation of the tool by pregnant women and new mothers using the tool. A purposive sample of 32 individual semistructured interviews and 7 focus groups were conducted, across five provinces in South Africa. All the sessions were transcribed and then analysed using a contextualised interpretative approach, with the assistance of Atlas.ti. The women were consistently positive about MomConnect, attaching high value to the content of the messages and the medium in which they were delivered. The system was found to work well, with minor problems in some language translations. Respondents were enthusiastic about the messages, stating that the information was of great use and made them feel empowered in their role as a mother, with some saving the messages to use as a resource or to share with others. The most significant problems related to network coverage. There was strong support for this intervention to continue. Given the user acceptability of mHealth interventions, MomConnect appeared to meet the target of identifying and responding to the recipient’s needs.
Self-enrolment antenatal health promotion data as an adjunct to maternal clinical information systems in the Western Cape Province of South Africa
Authors: Heekes Alexa , Tiffin Nicki , Dane Pierre , Mutemaringa Themba , Smith Mariette , Zinyakatira Nesbert , Barron Peter , Seebregts Chris , Boulle Andrew
Published: April 2018

Information systems designed to support health promotion in pregnancy, such as the MomConnect programme, are potential sources of clinical information which can be used to identify pregnancies prospectively and early on. In this paper we demonstrate the feasibility and value of linking records collected through the MomConnect programme, to an emergent province-wide health information exchange in the Western Cape Province of South Africa, which already enumerates pregnancies from a range of other clinical data sources. MomConnect registrations were linked to pregnant women known to the public health services using the limited identifiers collected by MomConnect. Three-quarters of MomConnect registrations could be linked to existing pregnant women, decreasing over time as recording of the national identifier decreased. The MomConnect records were usually the first evidence of pregnancy in pregnancies which were subsequently confirmed by other sources. Those at lower risk of adverse pregnancy outcomes were more likely to register. In some cases, MomConnect was the only evidence of pregnancy for a patient. In addition, the MomConnect records provided gestational age information and new and more recently updated contact numbers to the existing contact registry. The pilot integration of the data in the Western Cape Province of South Africa demonstrates how a client-facing system can augment clinical information systems, especially in contexts where electronic medical records are not widely available.
Nursing workload, patient safety incidents and mortality: an observational study from Finland
Authors: Fagerström Lisbeth , Kinnunen Marina , Saarela Jan
Published: April 2018

Objective

To investigate whether the daily workload per nurse (Oulu Patient Classification (OPCq)/nurse) as measured by the RAFAELA system correlates with different types of patient safety incidents and with patient mortality, and to compare the results with regressions based on the standard patients/nurse measure.

Setting

We obtained data from 36 units from four Finnish hospitals. One was a tertiary acute care hospital, and the three others were secondary acute care hospitals.

Participants

Patients’ nursing intensity (249 123 classifications), nursing resources, patient safety incidents and patient mortality were collected on a daily basis during 1 year, corresponding to 12 475 data points. Associations between OPC/nurse and patient safety incidents or mortality were estimated using unadjusted logistic regression models, and models that adjusted for ward-specific effects, and effects of day of the week, holiday and season.

Primary and secondary outcome measures

Main outcome measures were patient safety incidents and death of a patient.

Results

When OPC/nurse was above the assumed optimal level, the adjusted odds for a patient safety incident were 1.24 (95% CI 1.08 to 1.42) that of the assumed optimal level, and 0.79 (95% CI 0.67 to 0.93) if it was below the assumed optimal level. Corresponding estimates for patient mortality were 1.43 (95% CI 1.18 to 1.73) and 0.78 (95% CI 0.60 to 1.00), respectively. As compared with the patients/nurse classification, models estimated on basis of the RAFAELA classification system generally provided larger effect sizes, greater statistical power and better model fit, although the difference was not very large. Net benefits as calculated on the basis of decision analysis did not provide any clear evidence on which measure to prefer.

Conclusions

We have demonstrated an association between daily workload per nurse and patient safety incidents and mortality. Current findings need to be replicated by future studies.
Cross-sectional study on the prevalence and predictors of pregnancy among women living in HIV discordant relationships in a rural Rakai cohort, Uganda
Authors: Nakiganda Lydia Jacenta , Agardh Anette , Asamoah Benedict Oppong
Published: April 2018

Objectives

This study examines the prevalence of pregnancy in serodiscordant couples and identifies predictors associated with pregnancy in rural Rakai, Uganda.

Study design

A population-based cross-sectional study that used data from the Rakai Community Cohort Study (RCCS).

Setting and participants

We used data from the RCCS survey round 17 (2015–2016), which included 488 women in serodiscordant relationships. This study was conducted in Rakai district, located in south-western Uganda.

Primary outcomes

Pregnancy status.

Statistical analysis

Multivariable modified Poisson regression using stepwise selection was used to determine characteristics and behaviours associated with pregnancy status.

Results

The prevalence of pregnancy was 12% in women among serodiscordant couples. HIV-negative women in serodiscordant couples had a slightly higher pregnancy prevalence rate (13.6%) compared with HIV-positive women in serodiscordant couples (11%). Factors significantly associated with higher prevalence of pregnancy were; younger age 15–24 years (prevalence risk ratio (PRR)=4.04; 95% CI 1.72 to 9.50), middle age 25–34 years (PRR=2.49; 95% CI 1.05 to 5.89), Christian religion (PRR=2.26; 95% CI 1.41 to 3.63) and inconsistent condom use in the last 12 months (PRR=4.38, 95% CI 1.09 to 17.53). Neither HIV status nor HIV status disclosure was significantly associated with risk of getting pregnant.

Conclusion

Nearly 12% of women in serodiscordant relationships were pregnant, highlighting the need for integrated services to prevent unintended pregnancies and reduce conceptional related risks for those choosing to conceive. Association with younger age and inconsistent condom use suggests a role for early and continued couple-based conception counselling.
Health-related quality of life in Chinese inpatients with lung cancer treated in large general hospitals: across-sectional study
Authors: Gu Wen , Xu Yan-Min , Zhong Bao-Liang
Published: April 2018

Objective

In China, psychosocial problems of patients with cancer are under-recognised and undertreated in medical oncology practice. This study examined the health-related quality of life (QOL) in inpatients with lung cancer treated in large general hospitals and explored the demographic, clinical and psychosocial factors associated with QOL.

Design

Cross-sectional study.

Participants and setting

Altogether, 148 inpatients with lung cancer were consecutively recruited from two large general hospitals in Tianjin, China.

Main outcome measured

QOL, pain intensity, depressive and anxiety symptoms, and social support were assessed with WHO QOL Scale Brief Version, four-point Verbal Rating Scale, Hospital Anxiety and Depression Scale and Social Support Rating Scale, respectively.

Results

Compared with the normative data for the Chinese general population, patients had significantly lower scores in physical (t=−25.860, p<0.001) and psychological (t=−18.225, p<0.001) QOL. Being unmarried (β=−2.471, 95% CI −4.908 to –0.034), poor economic status (β=−1.764, 95% CI −2.964 to –0.564), cancer metastasis (β=−1.328, 95% CI −2.632 to –0.024), poor performance status (β=−0.959, 95% CI −1.542 to –0.376), depression (β=−0.465, 95% CI −0.631 to –0.299), anxiety (β=−0.208, 95% CI −0.354 to –0.062) and low utilisation of social support (β=−0.344, 95% CI −0.577 to –0.111) were independently associated with poor physical QOL, while female gender (β=−1.494, 95% CI −0.649 to –2.339), less education years (β=−0.209, 95% CI −0.294 to –0.123), currently receiving chemotherapy (β=−1.536, 95% CI −3.051 to –0.021), small-cell cancer (β=−1.157, 95% CI −2.223 to –0.091), more intense pain (β=−0.535, 95% CI −0.919 to –0.151), poor performance status (β=−0.930, 95% CI −1.383 to –0.477), anxiety (β=−0.178, 95% CI −0.248 to –0.108) and inadequate subjective social support (β=−0.137, 95% CI −0.153 to –0.121) were independently associated with poor psychological QOL.

Conclusions

Inpatients with lung cancer treated in Chinese large general hospitals have poorer QOL than the general population. Effective prevention and management of psychosocial problems are potentially effective to improve their QOL.
Hypertensive pregnancy complications in women with epilepsy and antiepileptic drugs: a population-based cohort study of first pregnancies in Norway
Authors: Danielsson Kim Christian , Borthen Ingrid , Morken Nils-Halvdan , Gilhus Nils Erik
Published: April 2018

Objectives

To estimate the risk of hypertensive pregnancy complications in women with epilepsy, with and without antiepileptic drugs, and assess the risk associated with the four most common antiepileptic drugs.

Design

A population-based cohort study using linked data from the Medical Birth Registry of Norway and the Norwegian Prescription Database. Women with epilepsy with and without antiepileptic drugs were compared with women without epilepsy.

Setting

Norway, 2004–2012.

Participants

All first pregnancies of women with epilepsy and women without epilepsy were included.

Primary and secondary outcome measures

Main outcome measures were hypertensive pregnancy complications: a compound variable of any hypertensive disorder, gestational hypertension, mild pre-eclampsia, severe pre-eclampsia, early onset pre-eclampsia, eclampsia and HELLP syndrome (haemolysis, elevated liver enzymes, low platelets).

Results

In total, 1778 pregnancies in women with epilepsy and 221 662 in women without epilepsy were analysed. 682 of the women with epilepsy used antiepileptic drugs, the most common in monotherapy being: lamotrigine (n=280), carbamazepine (n=94), levetiracetam (n=71) and valproate (n=51). There was an increased risk of any hypertensive disorder in women with epilepsy (adjusted OR (aOR) 1.2, 95% CI 1.0 to 1.5) and in the subcategory using valproat (aOR 2.9, 95% CI 1.3 to 6.4). The most frequent hypertensive complication was mild pre-eclampsia and the risk was increased in women with epilepsy (aOR 1.4, 95% CI 1.1 to 1.8) and women with epilepsy with valproat (aOR 3.3, 95% CI 1.2 to 9.4).

Conclusions

Women with epilepsy have an increased risk of mild pre-eclampsia, but not for the severe types of hypertensive pregnancy complications. Lamotrigine and levetiracetam do not predispose for mild pre-eclampsia, whereas valproate was associated with an increased risk of mild pre-eclampsia.
Endoscopy in 2017: a national survey of practice in the UK
Authors: Shenbagaraj Lavanya , Thomas-Gibson Siwan , Stebbing John , Broughton Raphael , Dron Michael , Johnston Debbie , Shaw Tim , Haboubi Hasan Nadim , Green John T
Published: April 2018

Introduction

The Joint Advisory Group on Gastrointestinal Endoscopy (JAG), hosted by the Royal College of Physicians, London, oversees the quality assurance of endoscopy services across the UK. Additional questions focusing on the pressures faced by endoscopy units to meet targets were added to the 2017 annual Global Rating Scale (GRS) return. This provides a unique insight into endoscopy services across all nations of the UK involving the acute and non-acute Nation Health Service sector as well as the independent sector.

Methods

All 508 services who are registered with JAG were asked to complete every field of the survey online in order to submit their completed April 2017 GRS return.

Results

A number of services reported difficulty in meeting national waiting time targets with a national average of only 55% of units meeting urgent cancer wait targets. Many services were insourcing or outsourcing patients to external providers to improve waiting times. Services are striving hard to increase capacity by backfilling lists and working weekends. Data collection was done in most units to reflect productivity but not to look at demand and capacity. Some of the units did not have an agreed capacity plan. The Did Not Attend rates for patients in the bowel cancer screening programme were much lower compared with standard lists.

Conclusion

This review highlights the increased pressure endoscopy services are under and the ‘just about coping’ situation. This is the first published overview of different aspects of UK-wide endoscopy services and the future challenges.
Controlled ecological evaluation of an implemented exercise training programme to prevent lower limb injuries in sport: differences in implementation activity
Authors: Donaldson Alex , Gabbe Belinda J , Lloyd David G , Cook Jill , Finch Caroline F
Published: April 2018

Objective

The public health benefits of injury prevention programmes are maximised when programmes are widely adopted and adhered to. Therefore, these programmes require appropriate implementation support. This study evaluated implementation activity outcomes associated with the implementation of FootyFirst, an exercise training injury prevention programme for community Australian football, both with (FootyFirst+S) and without (FootyFirst+NS) implementation support.

Method

An evaluation plan based on the Reach Effectiveness Adoption Implementation Maintenance (RE-AIM) Sports Setting Matrix was applied in a controlled ecological evaluation of the implementation of FootyFirst. RE-AIM dimension-specific (range: 0–2) and total RE-AIM scores (range: 0–10) were derived by triangulating data from a number of sources (including surveys, interviews, direct observations and notes) describing FootyFirst implementation activities. The mean dimension-specific and total scores were compared for clubs in regions receiving FootyFirst+S and FootyFirst+NS, through analysis of variance.

Results

The mean total RE-AIM score forclubs in the FootyFirst+S regions was 2.4 times higher than for clubs in the FootyFirst+NS region (4.73 vs 1.94; 95% CI for the difference: 1.64 to 3.74). Similarly, all dimension-specific scores were significantly higher for clubs in the FootyFirst+S regions compared with clubs in the FootyFirst+NS region. In all regions, the dimension-specific scores were highest for reach and adoption, and lowest for implementation.

Conclusion

Implementing exercise training injury prevention programmes in community sport is challenging. Delivering programme content supported by a context-specific and evidence-informed implementation plan leads to greater implementation activity, which is an important precursor to injury reductions.
Unintentional drowning mortality in China, 2006–2013
Authors: Wang Lijun , Cheng Xunjie , Yin Peng , Cheng Peixia , Liu Yunning , Schwebel David C , Liu Jiangmei , Qi Jinlei , Zhou Maigeng , Hu Guoqing
Published: April 2018

Background

Epidemiological characteristics and recent trends in unintentional drowning at the national level in China are unreported.

Methods

Using data from the Disease Surveillance Points system, the overall, sex-, location-, age- and cause-specific age-standardised mortality from unintentional drowning in China were calculated and compared. Linear regression was used to examine the significance of mortality trend changes over time.

Results

The average mortality was 4.05 per 100 000 persons between 2006 and 2013. Men and rural residents had much higher drowning mortality rates than women and urban residents at all time points. Drowning following a fall into natural water was the most common mechanism (46% of all drowning deaths). The overall drowning mortality rate remained stable for all subgroups except for distinct decreases in urban residents, children aged 5–9 years, and other specified and unspecified drowning (−10%, −36% and −25%, respectively).

Conclusions

The overall drowning mortality rate remained high and stable in China between 2006 and 2013. Effective prevention measures like removing or covering water hazards, wearing personal floatation devices, supervision of children, and teaching survival swimming and resuscitation skills should be implemented nationwide.
Coordinating Supply Chain with Buy-Back Contracts in the Presence of Risk Aversion
Authors: Luo Chunlin , Tian Xin , Mao Xiaobing , Cai Qiang
Published: April 2018

This paper addresses the operational decisions and coordination of the supply chain in the presence of risk aversion, where the risk averse retailer’s performance is measured by a combination of the expected profit and conditional value-at-risk (CVaR). Such performance measure reflects the desire of the retailer to maximize the expected profit on one hand and to control the downside risk of the profit on the other hand. The impact of risk aversion on the supply chain’s decision and performance is also explored. To overcome the inefficiency due to the double marginalization and the aggravation resulting from risk aversion, we investigate the buy-back contract to coordinate the supply chain. Such contract can largely increase the supply chain’s profit, especially when the retailer is more risk averse. Lastly, we extend such risk measure to the widely-used business model nowadays — platform selling model, and explore the impact of the allocation rule on the manufacturer’s decision.
Quantum no-singularity theorem from geometric flows
Authors: Alsaleh Salwa , Alasfar Lina , Faizal Mir , Ali Ahmed Farag
Published: April 2018

In this paper, we analyze the classical geometric flow as a dynamical system. We obtain an action for this system, such that its equation of motion is the Raychaudhuri equation. This action will be used to quantize this system. As the Raychaudhuri equation is the basis for deriving the singularity theorems, we will be able to understand the effects and such a quantization will have on the classical singularity theorems. Thus, quantizing the geometric flow, we can demonstrate that a quantum space–time is complete (nonsingular). This is because the existence of a conjugate point is a necessary condition for the occurrence of singularities, and we will be able to demonstrate that such conjugate points cannot occur due to such quantum effects.
Distribution law of the Dirac eigenmodes in QCD
Authors: Catillo Marco , Glozman Leonid Ya.
Published: April 2018

The near-zero modes of the Dirac operator are connected to spontaneous breaking of chiral symmetry in QCD (SBCS) via the Banks–Casher relation. At the same time, the distribution of the near-zero modes is well described by the Random Matrix Theory (RMT) with the Gaussian Unitary Ensemble (GUE). Then, it has become a standard lore that a randomness, as observed through distributions of the near-zero modes of the Dirac operator, is a consequence of SBCS. The higher-lying modes of the Dirac operator are not affected by SBCS and are sensitive to confinement physics and related [Formula: see text] and [Formula: see text] symmetries. We study the distribution of the near-zero and higher-lying eigenmodes of the overlap Dirac operator within [Formula: see text] dynamical simulations. We find that both the distributions of the near-zero and higher-lying modes are perfectly described by GUE of RMT. This means that randomness, while consistent with SBCS, is not a consequence of SBCS and is linked to the confining chromo-electric field.
On braneworld inverse power-law inflation
Authors: Es-sobbahi H. , Nach M.
Published: April 2018

In the framework of the braneworld Randall–Sundrum type II model, we investigate an inflationary scalar model in the high-energy regime. In this regime, the slow-roll parameters and the perturbation spectrum of the model are derived. The corresponding results are dealt with according to the known observational data. Then the solutions to the equations of motion on the brane are given.
Adinkras from ordered quartets of BC4 Coxeter group elements and regarding another Gadget’s 1,358,954,496 matrix elements
Authors: Gates S. James , Kang Lucas , Kessler David S. , Korotkikh Vadim
Published: April 2018

A Gadget, more precisely a scalar Gadget, is defined as a mathematical calculation acting over a domain of one or more adinkra graphs and whose range is a real number. A 2010 work on the subject of automorphisms of adinkra graphs, implied the existence of multiple numbers of Gadgets depending on the number of colors under consideration. For four colors, this number is two. In this work, we verify the existence of a second such Gadget and calculate (both analytically and via explicit computer-enabled algorithms) its 1,358,954,496 matrix elements over 36,864 minimal valise adinkras related to the Coxeter Group BC4.
Bandgap control and optical properties of β-Si3N4by single- and co-doping from a first-principles simulation
Authors: Lu Xuefeng , Gao Xu , Ren Junqiang , Li Cuixia , Guo Xin , Wei Yupeng , La Peiqing
Published: April 2018

Bandgap tailoring of [Formula: see text]-Si3N4is performed by single and co-doping by using density functional theory (DFT) of PBE functional and plane-wave pseudopotential method. The results reveal that a direct bandgap transfers into an indirect one when single-doped with As element. Also, a considerate decrease of bandgap to 0.221 eV and 0.315 eV is present for Al–P and As–P co-doped systems, respectively, exhibiting a representative semiconductor property that is characteristic for a narrower bandgap. Compared with other doped systems, Al-doped system with formation energy of 2.67 eV is present for a more stable structure. From charge density difference (CDD) maps, it is found that the blue area between co-doped atoms increases, illustrating an enhancement of covalent property for Al–P and Al–As bonds. Moreover, a slightly obvious “Blue shift” phenomenon can be obtained in Al, Al–P and Al–As doped systems, indicating an enhanced capacity of responses to light, which contributes to the insight for broader applications with regard to photoelectric devices.
Methods for Parallelizing Constraint Propagation through the Use of Strong Local Consistencies
Authors: Dasygenis Minas , Stergiou Kostas
Published: April 2018

Constraint programming (CP) is a powerful paradigm for various types of hard combinatorial problems. Constraint propagation techniques, such as arc consistency (AC), are used within solvers to prune inconsistent values from the domains of the variables and narrow down the search space. Local consistencies stronger than AC have the potential to prune the search space even more, but they are not widely used because they incur a high run time penalty in cases where they are unsuccessful. All constraint propagation techniques are sequential by nature, and thus they cannot be scaled up to modern multicore machines. For this reason, research on parallelizing constraint propagation is very limited. Contributing towards this direction, we exploit the parallelization possibilities of modern CPUs in tandem with strong local propagation methods in a novel way. Instead of trying to parallelize constraint propagation algorithms, we propose two search algorithms that apply different propagation methods in parallel. Both algorithms consist of a master search process, which is a typical CP solver, and a number of slave processes, with each one implementing a strong propagation method. The first algorithm runs the different propagators synchronously at each node of the search tree explored in the master process, while the second one can run them asynchronously at different nodes of the search tree. Preliminary experimental results on well-established benchmarks display the promise of our research by illustrating that our algorithms have execution times equal to those of serial solvers, in the worst case, while being faster in most cases.
Experimental Assessment of Differential Evolution with Grid-Based Parameter Adaptation
Authors: Tatsis Vasileios A. , Parsopoulos Konstantinos E.
Published: April 2018

Evolutionary algorithms have been long established as an essential field of research in Computational Intelligence. Differential Evolution is placed among the most successful algorithms of this type. However, it has proved to be highly sensitive on its parameters. For this purpose, offline and online parameter-control methods have been proposed. Recently, a grid-based parameter adaptation procedure was introduced and successfully applied on Differential Evolution. Despite the generality of the method, the resulting algorithm was capable to compete with already tuned adaptive algorithms on high-dimensional test problems without any additional preprocessing. The present work extends the experimental study of this approach on the state-of-the-art CEC-2013 test suite. Two variants of the algorithm are considered and different initial conditions are tested to shed light on its performance aspects. Comparisons with other algorithms as well as between the proposed approaches are reported. The results verify the potential of the grid-based parameter adaptation method as a general-purpose alternative for parameter setting.
Inverse problem: What can we tell about the matter and energy in our Universe from its dimensionality and evolution
Authors: Makaruk Hanna , Langenbrunner James
Published: April 2018

The most popular theories of everything are various versions of the superstring theory. The theories require existence of additional space dimensions, vibrations of which create the material particles in [Formula: see text] space. The additional space dimensions are understood as being currently smaller than the Planck Length and due to this not directly observable. We search for multidimensional models of the Universe (one time dimension; three isotropic, flat external dimensions, and [Formula: see text]-internal dimensions), which satisfy the multidimensional Einstein equations and which started from the same radius of all of the internal and external dimensions, with an anisotropic energy–momentum tensor. Analytical solution of [Formula: see text]-dimensional Einstein equation in a reparameterized time is reminded and discussed. The energy–momentum tensor is solely responsible for expansion of the external dimensions and shrinking of the internal ones; and to obtain this behavior of the space the tensor needs to fulfill some conditions i.e. the energy–momentum tensor cannot include only radiation, vacuum and baryonic matter. For the behavior of the physical space consistent with the one observed in our Universe, the dark energy and/or dark matter have to exist.
Analytical and numerical analysis of the complete Lipkin–Meshkov–Glick Hamiltonian
Authors: Co’ Giampaolo , De Leo Stefano
Published: April 2018

The Lipkin–Meshkov–Glick is a simple, but not trivial, model of a quantum many-body system which allows us to solve the many-body Schrödinger equation without making any approximation. The model, which in its unperturbed case is composed only by two energy levels, includes two interacting terms. A first one, the [Formula: see text] interaction, which promotes or degrades pairs of particles, and a second one, the [Formula: see text] interaction, which scatters one particle in the upper and another in the lower energy level. In comparing this model with other approximation methods, the [Formula: see text] term interaction is often set to zero. In this paper, we show how the presence of this interaction changes the global structure of the system, generates degeneracies between the various eigenstates and modifies the energy eigenvalues structure. We present analytical solutions for systems of two and three particles and, for some specific cases, also for four, six and eight particles. The solutions for systems with more than eight particles are only numerical but their behavior can be well understood by considering the extrapolations of the analytical results. Of particular interest is the study of how the [Formula: see text] interaction affects the energy gap between the ground state and the first-excited state.
Equality of derival automorphisms and certain automorphisms in finitely generated groups
Authors: Azhdari Zahedeh
Published: April 2018

Let [Formula: see text] be a group and [Formula: see text], [Formula: see text], [Formula: see text] and [Formula: see text] denote the group of all inner automorphisms, the group of all pointwise inner automorphisms, the group of all central automorphisms and the group of all derival automorphisms of [Formula: see text], respectively. We know that in a finite [Formula: see text]-group [Formula: see text] of class 2, [Formula: see text] if and only if [Formula: see text] is cyclic and [Formula: see text], where [Formula: see text] is the group of all derival automorphisms of [Formula: see text] which fix [Formula: see text] elementwise. In this paper, we characterize all finite nilpotent groups of class 2 for which [Formula: see text] or [Formula: see text] is equal to [Formula: see text], [Formula: see text], [Formula: see text] and [Formula: see text]. Also, we characterize all finitely generated nilpotent groups of class 2 for which [Formula: see text] is equal to [Formula: see text] and give some interesting corollaries in this regard.
Sparse time-frequency representation based on multiwindow discrete Gabor transform
Authors: Li Rui , Zhou Jian
Published: April 2018

The multiwindow discrete Gabor transform (M-DGT) is an important time-frequency analysis tool in many applications. In this paper, sparse time-frequency representation (TFR) based on M-DGT with sparse regularization theory is presented. The M-DGT is first formulated as a convex constrained optimization model by minimizing the objective function with a mixed [Formula: see text]–[Formula: see text] norm of the M-DGT coefficients. Then, an iterative algorithm based on the split Bergman method is utilized to compute the sparse Gabor time-frequency spectrum of the analyzed signal. According to the Heisenberg uncertainty principle, using an analysis window with good time resolution in M-DGT will lead to the Gabor TFR with high frequency resolution and vice versa. To obtain the sparse TFR with good time-frequency resolution (or concentration), the sparse spectra of M-DGT can be combined by the arithmetic average or the geometric average. Numerical experiments clearly show that the proposed method is an effective and powerful tool for analyzing nonstationary signals, by which the high time-frequency concentration (or resolution) of the Gabor time-frequency spectrum can be obtained as compared to traditional M-DGT.
Key rate estimation of measurement-device-independent quantum key distribution protocol in satellite-earth and intersatellite links
Authors: Khaleel Ahmed Ismael , Tawfeeq Shelan Khasro
Published: April 2018

In this work, an estimation of the key rate of measurement-device-independent quantum key distribution (MDI-QKD) protocol in free space was performed. The examined free space links included satellite-earth downlink, uplink and intersatellite link. Various attenuation effects were considered such as diffraction, atmosphere, turbulence and the efficiency of the detection system. Two cases were tested: asymptotic case with infinite number of decoy states and one-decoy state case. The estimated key rate showed the possibility of applying MDI-QKD in earth-satellite and intersatellite links, offering longer single link distance to be covered.
Golf Clubhead Optimization Based on Contribution of Eigenmodes
Authors: Wu Zhiqiang , Sogabe Yuji , Arimitsu Yutaka
Published: April 2018

This study is aimed to optimize a golf clubhead for the purposes of maximizing the driving distance. Since the sensitivity-based approaches cannot be applied in impact problem, the authors developed an optimization system by using basis vector method. The relation between the eigenfrequencies and the coefficient of restitution is examined with finite element method (FEM) models numerically at first. Based on evaluating the contribution of eigenmodes, the authors proposed an approach to create the basis vectors using the sensitivity functions of eigenvalues. Computational results are presented for demonstrating the effectiveness of the proposed approach.
THE IMPACT OF VISUAL PERFORMANCE MANAGEMENT ON DECISION-MAKING IN THE ENTREPRENEURIAL PROCESS
Authors: AAS TOR HELGE , ALAASSAR AHMAD
Published: April 2018

Effective decision-making is critical for entrepreneurial success due to constantly changing customer needs. Research has indicated that visual performance management approaches have the potential to improve decision-making during operations in established firms. However, how visual performance management may affect decision-making during the entrepreneurial process has not yet been adequately addressed in the extant research literature. To contribute in filling this knowledge gap, a visual performance management tool called Obeya was adapted and utilised during an entrepreneurial process, and its impact on decision-making during the process was qualitatively explored. The findings indicate that the implementation of the Obeya tool has the potential to positively impact the ability to understand and communicate performance related information during the entrepreneurial process. Moreover, these effects may lead to improvements in decision-making. In addition, visual performance management may be a particularly powerful tool when it is combined with the implementation of iterative experimental entrepreneurial processes, such as Lean Startup.
FeCoNi sulphide-derived nanodots as electrocatalysts for efficient oxygen evolution reaction
Authors: Wang Han , Yang Jinlong , Yang Luyi , Zhang Guangxing , Liu Chaokun , Tang Hanting , Zhao Qinghe , Pan Feng
Published: April 2018

Although many single- and bi-metal sulfides were reported as bifunctional catalysts for oxygen evolution reaction (OER), The catalytic activity of trimetal sulfides was seldom reported and their catalytic mechanisms need to be further investigated. Herein, trimetal FeCoNi sulphide nanostructures (MSx, M [Formula: see text] FeCoNi) are grown on carbon paper as OER catalytic electrodes for alkaline water splitting. The MSx outperforms the state-of-the-art IrO2 in 1[Formula: see text]M KOH with a reduced overpotential of 250[Formula: see text]mV and a superior Tafel Slope of 30[Formula: see text]mV dec[Formula: see text]. It is found that after OER the morphologies of MSx change to nanodots with the smaller size (3–5[Formula: see text]nm), therefore, the shorter hydrogen bond on the surfaces of MSx-derived nanodots may enable to significantly reduce kinetic energy barriers for H2O-splitting.
Superconducting Gap in s±-Wave Iron-Based Superconductors
Authors: Pradhan B. , Goi S. K. , Mishra R. N.
Published: April 2018

We present a theoretical model study of superconductivity for iron-based high-[Formula: see text] superconductors in s[Formula: see text]-wave symmetry, considering two degenerate orbitals and the electron hopping up to the third nearest neighbor as a two-orbital model. The analytic expression for the temperature dependence of the superconducting order parameter is derived by Zubarev’s technique of double time single particle Green’s function method and solved self-consistently. The effect of inter orbital hopping on the superconducting energy gap parameter and electronic specific heat is studied.
Sustainability, hope, and designerly action in the anthropocene
Authors: Bendor Roy
Published: April 2018

In this forum we highlight innovative thought, design, and research in the area of interaction design and sustainability, illustrating the diversity of approaches across HCI communities.
--- Roy Bendor, Editor
My users taught me to read with my ears
Authors: Romero Mario
Published: April 2018

The
Interactions
website (interactions.acm.org) hosts a stable of bloggers who share insights and observations on HCI, often challenging current practices. Each issue we'll publish selected posts from some of the leading and emerging voices in the field.
ACM fellows in the SIGMM community
Authors: Smeaton Alan
Published: April 2018

Multimedia can be defined as the seamless integration of digital technologies in ways which provide for an enriched experience for users as we create and consume information with high fidelity. Behind that definition lies a host of enabling digital technologies to allow us create, capture, store, analyse, index, locate, transmit and present information. But when did multimedia, as we now know it, start? Was it the ideas of Vannevar Bush and Memex, or Ted Nelson and Xanadu or the development of Apple computers in the mid 1980s or maybe the emergence of the web which enables distribution of multimedia?
MPEG column
Authors: Timmerer Christiam
Published: April 2018

The original blog post can be found at the Bitmovin Techblog (https://bitmovin.com/mpeg-121-meeting-report/) and has been updated here to focus on and highlight research aspects.
JPEG column
Authors: Pinheiro Antonio
Published: April 2018

The JPEG Committee had its 78th meeting in Rio de Janeiro, Brazil. Relevant to its ongoing standardization efforts in JPEG Privacy and Security, JPEG organized a special session to explore how to support blockchain and distributed ledger technologies to past, ongoing and future JPEG family of standards. This is motivated by the fact that considering the potential impact of such technologies in the future of multimedia, standardization will be required to enable interoperability between different systems and services of imaging relying on blockchain and distributed ledger technologies.
Socially significant music events
Authors: Yadati Karthik
Published: April 2018

http://osf.io/eydxk

Social media sharing platforms (e.g., YouTube, Flickr, Instagram, and SoundCloud) have revolutionized how users access multimedia content online. Most of these platforms provide a variety of ways for the user to interact with the different types of media: images, video, music. In addition to watching or listening to the media content, users can also engage with content in different ways, e.g., like, share, tag, or comment. Social media sharing platforms have become an important resource for scientific researchers, who aim to develop new indexing and retrieval algorithms that can improve users' access to multimedia content. As a result, enhancing the experience provided by social media sharing platforms.
Educational approach to cyber foundations in an undergraduate core program
Authors: Hussey Jason , Shaha Jacob
Published: April 2018

Maximizing a student's learning in a general education information technology course is critical when teachers have only a little time to cover numerous topics within the discipline. It is therefore paramount that programs utilize the most effective pedagogical approach to educating students on these topics. This allows teachers to take full advantage of this limited time per topic. The principal contribution of this paper is a statistical analysis of student performance in an intermediate-level information technology course when exposed to two popular methods of teaching information technology concepts. This course is part of the larger cyber education model at the United States Military Academy. Our study implemented and analyzed the results from a control group educated with systematic, skills-based instruction versus a treatment group where a problemcentered learning approach was utilized. Our experimental results provide statistically significant reinforcement of the idea that problem-centered learning is superior to skills-based instruction for educating students in information technology topics as a part of their cyber education.
Label Distribution Learning by Regularized Sample Self-Representation
Authors: Yang Wenyuan , Li Chan , Zhao Hong
Published: April 2018

Multilabel learning that focuses on an instance of the corresponding related or unrelated label can solve many ambiguity problems. Label distribution learning (LDL) reflects the importance of the related label to an instance and offers a more general learning framework than multilabel learning. However, the current LDL algorithms ignore the linear relationship between the distribution of labels and the feature. In this paper, we propose a regularized sample self-representation (RSSR) approach for LDL. First, the label distribution problem is formalized by sample self-representation, whereby each label distribution can be represented as a linear combination of its relevant features. Second, the LDL problem is solved by L2-norm least-squares and L2,1-norm least-squares methods to reduce the effects of outliers and overfitting. The corresponding algorithms are named RSSR-LDL2 and RSSR-LDL21. Third, the proposed algorithms are compared with four state-of-the-art LDL algorithms using 12 public datasets and five evaluation metrics. The results demonstrate that the proposed algorithms can effectively identify the predictive label distribution and exhibit good performance in terms of distance and similarity evaluations.
Mechanisms of Hearing Loss in a Guinea Pig Model of Superior Semicircular Canal Dehiscence
Authors: Tong Bu-Sheng , He Zi-Yu , Ding Chen-Ru , Yang Juan-Mei , Wang Jing , Han Zhao , Huang Yi-Bo , Gao Na , Jia Xian-Hao , Chi Fang-Lu , Ren Dong-Dong
Published: April 2018

Defective acoustic transmission in the cochlea is closely related with various auditory and vestibular symptoms. Among them, semicircular canal dehiscence (SCD) with a defective semicircular bone is typical. Currently, the pathogenesis of SCD is usually explained by the third window hypothesis; however, this hypothesis fails to explain the variability in the symptoms and signs experienced by superior SCD (SSCD) patients. We evaluated the mechanism of hearing loss in a guinea pig model of bony dehiscence with various sizes and locations along the superior semicircular canal. Auditory brainstem responses (ABRs) and laser Doppler velocimetry were used to measure hearing loss and vibration changes before and after fenestration, as well as after restorative patching. ABR thresholds at low frequencies (e.g., 1000 Hz) increased after fenestration and decreased back to the normal range after we repaired the defect. Energy leakage from the surgically introduced third window was detected in the range of 300–1500 Hz, accompanied by increased vibration at the umbo, stapes head, and the dehiscence site, while decreased vibration was observed at the round window membrane in the same frequency range. After the patching procedure, the deviant vibrations were recovered. The degree of postfenestration energy leakage was proportional to the size of fenestration and the proximity of the fenestration site to the oval window. These results suggest that the bony fenestration of the superior semicircular canal mimics the hearing loss pattern of patients with SSCD. The decrease in perilymph wave impedance likely accounts for the auditory changes.
Drosophila melanogasteras a Model for Diabetes Type 2 Progression
Authors: Álvarez-Rendón Jéssica P. , Salceda Rocío , Riesgo-Escovar Juan R.
Published: April 2018

Drosophila melanogasterhas been used as a very versatile and potent model in the past few years for studies in metabolism and metabolic disorders, including diabetes types 1 and 2.Drosophilainsulin signaling, despite having seven insulin-like peptides with partially redundant functions, is very similar to the human insulin pathway and has served to study many different aspects of diabetes and the diabetic state. Yet, very few studies have addressed the chronic nature of diabetes, key for understanding the full-blown disease, which most studies normally explore. One of the advantages of havingDrosophilamutant viable combinations at different levels of the insulin pathway, with significantly reduced insulin pathway signaling, is that the abnormal metabolic state can be studied from the onset of the life cycle and followed throughout. In this review, we look at the chronic nature of impaired insulin signaling. We also compare these results to the results gleaned from vertebrate model studies.