bluuebunny/crossref_metadata_2025 huggingface dataset:
Genomic Characterization of a Pattern D Streptococcus pyogenes
emm53
Isolate Reveals a Genetic Rationale for Invasive Skin Tropicity
Authors: Bao Yun-Juan , Liang Zhong , Mayfield Jeffrey A. , Donahue Deborah L. , Carothers Katelyn E. , Lee Shaun W. , Ploplis Victoria A. , Castellino Francis J.
Published: April 2016

The genome of an invasive skin-tropic strain (AP53) of serotype M53 group A
Streptococcus pyogenes
(GAS) is composed of a circular chromosome of 1,860,554 bp and carries genetic markers for infection at skin locales,
viz
.,
emm
gene family pattern D and FCT type 3. Through genome-scale comparisons of AP53 with other GAS genomes, we identified 596 candidate single-nucleotide polymorphisms (SNPs) that reveal a potential genetic basis for skin tropism. The genome of AP53 differed by ∼30 point mutations from a noninvasive pattern D serotype M53 strain (Alab49), 4 of which are located in virulence genes. One pseudogene, yielding an inactive sensor kinase (CovS
−
) of the two-component transcriptional regulator CovRS, a major determinant for invasiveness, severely attenuated the expression of the secreted cysteine protease SpeB and enhanced the expression of the hyaluronic acid capsule compared to the isogenic noninvasive AP53/CovS
+
strain. The collagen-binding protein transcript
sclB
differed in the number of 5′-pentanucleotide repeats in the signal peptides of AP53 and Alab49 (9 versus 15), translating into different lengths of their signal peptides, which nonetheless maintained a full-length translatable coding frame. Furthermore, GAS strain AP53 acquired two phages that are absent in Alab49. One such phage (ΦAP53.2) contains the known virulence factor superantigen exotoxin gene tandem
speK-slaA
. Overall, we conclude that this bacterium has evolved in multiple ways, including mutational variations of regulatory genes, short-tandem-repeat polymorphisms, large-scale genomic alterations, and acquisition of phages, all of which may be involved in shaping the adaptation of GAS in specific infectious environments and contribute to its enhanced virulence.

IMPORTANCE
Infectious strains of
S. pyogenes
(GAS) are classified by their serotypes, relating to the surface M protein, the
emm
-like subfamily pattern, and their tropicity toward the nasopharynx and/or skin. It is generally agreed that M proteins from pattern D strains, which also directly bind human host plasminogen, are skin tropic. We have sequenced and characterized the genome of an invasive pattern D GAS strain (AP53) in comparison to a very similar strain (Alab49) that is noninvasive and developed a genomic rationale as to possible reasons for the skin tropicity of these two strains and the greater invasiveness of AP53.
Type IV Pilus Expression Is Upregulated in Nontypeable Haemophilus influenzae Biofilms Formed at the Temperature of the Human Nasopharynx
Authors: Mokrzan Elaine M. , Ward Michael O. , Bakaletz Lauren O.
Published: April 2016

NontypeableHaemophilus influenzae(NTHI), a commensal of the human nasopharynx (hNP), is a common cause of biofilm-associated diseases of the respiratory tract. However, NTHI biofilm biology at the average hNP temperature, i.e., 34°C, has not been well studied. Here we grew NTHI biofilms at 34°C and 37°C, to evaluate relative biofilm growth, expression, and function of the type IV pilus (Tfp), a critical adhesin important for NTHI biofilm formation. The kinetics and regulation of Tfp expression in NTHI biofilms are unclear, especially at 34°C. Tfp expression, as estimated bypilApromoter activity, was distributed throughout the biofilms, with a unique pattern that was dependent on temperature, time in culture, and position within the maturing biofilm. Tfp expression was required for the formation of the characteristic tower structures of NTHI biofilms and was significantly upregulated in NTHI biofilms formed at 34°C versus 37°C. This increase correlated with significantly greater twitching motility at 34°C than at 37°C. Treatment with antisera targeting the major subunit of Tfp (PilA) significantly inhibited NTHI biofilm formation at both temperatures, confirming the importance of this critical adhesin in biofilm formation. Additionally, treatment of preestablished biofilms with antisera against PilA significantly decreased biofilm biomass and mean thickness at both temperatures. These results demonstrated a pivotal role for Tfp in NTHI biofilm formation and stability at the temperature of the hNP, and they underscore the utility of PilA as a vaccine candidate for treatment and/or prevention of NTHI biofilm-associated diseases.

IMPORTANCENTHI is an important cause of chronic respiratory tract infections, including otitis media, chronic rhinosinusitis, and exacerbations of chronic obstructive pulmonary disease and cystic fibrosis. The chronic and recurrent nature of these diseases is attributed to the presence of bacterial biofilms, which are highly resistant to antimicrobials. We characterized NTHI biofilm growth and expression of PilA, the major subunit of the Tfp, at the temperature of the hNP, which is the commensal habitat of NTHI. Our results expand the current understanding of the role of Tfp during biofilm formation and maturation at the temperature of both the hNP and the middle ear, and they strengthen support for PilA as a vaccine candidate for the prevention and treatment of NTHI biofilm-associated diseases.
Adaptor Scaffoldins: An Original Strategy for Extended Designer Cellulosomes, Inspired from Nature
Authors: Stern Johanna , Moraïs Sarah , Lamed Raphael , Bayer Edward A.
Published: April 2016

Designer cellulosomes consist of chimeric cohesin-bearing scaffoldins for the controlled incorporation of recombinant dockerin-containing enzymes. The largest designer cellulosome reported to date is a chimeric scaffoldin that contains 6 cohesins. This scaffoldin represented a technical limit of sorts, since adding another cohesin proved problematic, owing to resultant low expression levels, instability (cleavage) of the scaffoldin polypeptide, and limited numbers of available cohesin-dockerin specificities—the hallmark of designer cellulosomes. Nevertheless, increasing the number of enzymes integrated into designer cellulosomes is critical, in order to further enhance degradation of plant cell wall material. Adaptor scaffoldins comprise an intermediate type of scaffoldin that can both incorporate various enzymes and attach to an additional scaffoldin. Using this strategy, we constructed an efficient form of adaptor scaffoldin that possesses three type I cohesins for enzyme integration, a single type II dockerin for interaction with an additional scaffoldin, and a carbohydrate-binding module for targeting to the cellulosic substrate. In parallel, we designed a hexavalent scaffoldin capable of connecting to the adaptor scaffoldin by the incorporation of an appropriate type II cohesin. The resultant extended designer cellulosome comprised 8 recombinant enzymes—4 xylanases and 4 cellulases—thereby representing a potent enzymatic cocktail for solubilization of natural lignocellulosic substrates. The contribution of the adaptor scaffoldin clearly demonstrated that proximity between the two scaffoldins and their composite set of enzymes is crucial for optimized degradation. After 72 h of incubation, the performance of the extended designer cellulosome was determined to be approximately 70% compared to that of native cellulosomes.

IMPORTANCE
Plant cell wall residues represent a major source of renewable biomass for the production of biofuels such as ethanol via breakdown to soluble sugars. The natural microbial degradation process, however, is inefficient for achieving cost-effective processes in the conversion of plant-derived biomass to biofuels, either from dedicated crops or human-generated cellulosic wastes. The accumulation of the latter is considered a major environmental pollutant. The development of designer cellulosome nanodevices for enhanced plant cell wall degradation thus has major impacts in the fields of environmental pollution, bioenergy production, and biotechnology in general. The findings reported in this article comprise a true breakthrough in our capacity to produce extended designer cellulosomes via synthetic biology means, thus enabling the assembly of higher-order complexes that can supersede the number of enzymes included in a single multienzyme complex.
Behaviour-change intervention in a multicentre, randomised, placebo-controlled COPD study: methodological considerations and implementation
Authors: Bourbeau Jean , Lavoie Kim L , Sedeno Maria , De Sousa Dorothy , Erzen Damijan , Hamilton Alan , Maltais François , Troosters Thierry , Leidy Nancy
Published: April 2016

Introduction

Chronic obstructive pulmonary disease is generally progressive and associated with reduced physical activity. Both pharmacological therapy and exercise training can improve exercise capacity; however, these are often not sufficient to change the amount of daily physical activity a patient undertakes. Behaviour-change self-management programmes are designed to address this, including setting motivational goals and providing social support. We present and discuss the necessary methodological considerations when integrating behaviour-change interventions into a multicentre study.

Methods and analysis

PHYSACTO is a 12-week phase IIIb study assessing the effects on exercise capacity and physical activity of once-daily tiotropium+olodaterol 5/5 µg with exercise training, tiotropium+olodaterol 5/5 µg without exercise training, tiotropium 5 µg or placebo, with all pharmacological interventions administered via the Respimat inhaler. Patients in all intervention arms receive a behaviour-change self-management programme to provide an optimal environment for translating improvements in exercise capacity into increases in daily physical activity. To maximise the likelihood of success, special attention is given in the programme to: (1) the Site Case Manager, with careful monitoring of programme delivery; (2) the patient, incorporating patient-evaluation/programme-evaluation measures to guide the Site Case Manager in the self-management intervention; and (3) quality assurance, to help identify and correct any problems or shortcomings in programme delivery and ensure the effectiveness of any corrective steps. This paper documents the comprehensive methods used to optimise and standardise the behaviour-change self-management programme used in the study to facilitate dialogue on the inclusion of this type of programme in multicentre studies.

Ethics and dissemination

The study has been approved by the relevant Institutional Review Boards, Independent Ethics Committee and Competent Authority according to national and international regulations. The results of this study will be disseminated through relevant, peer-reviewed journals and international conference presentations.

Trial registration number

NCT02085161.
Counterfeit medicines in Peru: a retrospective review (1997–2014)
Authors: Medina Edwin , Bel Elvira , Suñé Josep María
Published: April 2016

Objective

To consolidate and assess information on counterfeit medicines subject to pharmaceutical alerts issued by the Peruvian Medicines Regulatory Authority over 18 years (1997–2014) of health monitoring and enforcement.

Design

A retrospective review of drug alerts.

Setting

A search of the website of the General Directorate of Medicines, Supplies and Drugs (DIGEMID) of the Ministry of Health of Peru for drug alerts issued between 1997 and 2014.

Eligibility criteria

Drug alerts related to counterfeit medicines.

Results

A total of 669 DIGEMID alerts were issued during the study period, 354 (52.91%) of which cover 1738 cases of counterfeit medicines (many alerts deal with several cases at a time). 1010 cases (58.11%) involved pharmaceutical establishments and 349 (20.08%) involved non-pharmaceutical commercial outlets. In 126 cases (7.25%), counterfeit medicines were seized in an unauthorised trade (without any marketing authorisation); in 253 cases (14.56%) the type of establishment or business associated with the seized product was not identified.

Conclusions

Counterfeit medicines are a serious public health problem in Peru. A review of the data cannot determine whether counterfeit medicines in Peru increased during the study period, or if monitoring by different government health agencies highlighted the magnitude of the problem by providing more evidence. The problem is clearly structural, since the majority of cases (58.11% of the total) were detected in legitimate supply chains. Most counterfeit medicines involve staple pharmaceutical products and common dosage forms. Considerable work remains to be done to control the serious problem of counterfeit medicines in Peru.
Quality of relationships as predictors of outcomes in people with dementia: a systematic review protocol
Authors: Edwards Hannah B , Savović Jelena , Whiting Penny , Leach Verity , Richards Alison , Cullum Sarah , Cheston Richard
Published: April 2016

Introduction

Serious adverse outcomes for people with dementia include institutionalisation, hospitalisation, death, development of behavioural and psychiatric symptoms, and reduced quality of life. The quality of the relationship between the person with dementia and their informal/family carer is thought to affect the risk of these outcomes. However, little is known about which aspects of relationship quality are important, or how they affect outcomes for people with dementia.

Methods and analysis

This will be a systematic review of the literature. Electronic databases MEDLINE, EMBASE, Web of Science, PsycInfo, the Cochrane Database, ALOIS and OpenGrey will be searched from inception. 2 independent reviewers will screen results for eligibility with standardised criteria. Data will be extracted for relevant studies, and information on the associations between relationship quality and dementia outcomes will be synthesised. Meta-analysis will be performed if possible to calculate pooled effect sizes. Narrative synthesis will be performed if study heterogeneity rules out meta-analysis.

Ethics and dissemination

Ethical review is not necessary as this review summarises data from previous studies. Results will be disseminated via peer-reviewed publication. Results will also be disseminated to a patient and public involvement group and an expert panel for their views on the findings and implications for future work.

Trial registration number

CRD42015020518.
Patient attitudes about the clinical use of placebo: qualitative perspectives from a telephone survey
Authors: Ortiz Robin , Chandros Hull Sara , Colloca Luana
Published: April 2016

Objectives

To examine qualitative responses regarding the use of placebo treatments in medical care in a sample of US patients.

Survey studies suggest a deliberate clinical use of placebos by physicians, and prior research has found that although most US patients find placebo use acceptable, the rationale for these beliefs is largely unknown.

Setting

Members of the Outpatient Clinic at the Kaiser Permanente Northern California interviewed research participants who had been seen for a chronic health problem at least once in the prior 6 months.

Participants

853 women (61%) and men, white (58%) and non-white participants aged 18–75 years.

Primary and secondary outcomes

Qualitative responses on perceptions of placebo use from one-time telephone surveys were analysed for common themes and associations with demographic variables.

Results

Prior results indicated that a majority of respondents felt it acceptable for doctors to recommend placebo treatments. Our study found that a lack of harm (n=291, 46.1%) and potential benefit (n=250, 39.6%) were the most common themes to justify acceptability of placebo use. Responses citing potential benefit were associated with higher education (r=0.787; p<0.024). Of the minority of respondents who judged it never acceptable for doctors to recommend placebo treatments, the most often referenced rationale was obligation of the doctor to do more (n=102, 48.3%). Additional themes emerged around the issue of whether a doctor was transparent about placebo use, including honesty, patient's right to know and power of the mind. Older age was associated with likelihood to cite overall physician, as opposed to treatment, related themes (r=0.753; p<0.002).

Conclusions

Participants seem to appreciate and understand the lack of harm and potential benefit associated with placebo treatments, while valuing the role of the physician and the patient in its implementation.
Glycosylated haemoglobin for screening and diagnosis of gestational diabetes mellitus
Authors: Khalafallah Alhossain , Phuah Eileen , Al-Barazan Abdul Majeed , Nikakis Irena , Radford Andrea , Clarkson Wade , Trevett Clinton , Brain Terry , Gebski Val , Corbould Anne
Published: April 2016

Objectives

The oral glucose tolerance test (OGTT) is a cumbersome test that is time consuming, labour intensive and often poorly tolerated by pregnant women. To date, glycosylated haemoglobin (HbA1c) is the most accepted measure of chronic glycaemia outside of pregnancy. HbA1c is an uncomplicated test, less time consuming, does not require any specific patient preparation and is considered straightforward compared with the OGTT. Therefore, we prospectively tested the utility of the HbA1c when used as a screening tool in pregnancy for gestational diabetes mellitus (GDM).

Settings

Primary health care. Single tertiary referral centre, Tasmania, Australia.

Participants

A direct comparison between HbA1c levels and the OGTT results in pregnant women, tested concurrently at the 24–28 gestational week, was undertaken. A full profile of 480 pregnant women during the period from September 2012 to July 2014 was completed. Median and mean age of participants was 29 years (range 18–47 years).

Interventions

A simultaneous prospective assessment of HbA1c versus standard OGTT in a cohort of consecutive pregnant women presenting to our institute was performed.

Results

The number of women who had GDM according to OGTT criteria was 57, representing 11.9% of the evaluated 480 pregnant women. Using a cut-off value for HbA1c at 5.1% (32 mmol/mol) for detecting GDM showed sensitivity of 61% and specificity of 68% with negative predictive value (NPV) of 93%, versus sensitivity of 27% and specificity of 95% with NPV of 91% when using HbA1c cut-off value of 5.4% (36 mmol/mol).

Conclusions

Our results suggest that pregnant women with an HbA1c of≥5.4% (36 mmol/mol) should proceed with an OGTT. This may result in a significant reduction in the burden of testing on both patients and testing facility staff and resources. Further investigations are required to integrate and optimise the HbA1c as a single, non-fasting, screening tool for GDM.

Trial registration number

ACTRN12611000739910.
Improving feedback on junior doctors’ prescribing errors: mixed-methods evaluation of a quality improvement project
Authors: Reynolds Matthew , Jheeta Seetal , Benn Jonathan , Sanghera Inderjit , Jacklin Ann , Ingle Digby , Franklin Bryony Dean
Published: April 2016

Background

Prescribing errors occur in up to 15% of UK inpatient medication orders. However, junior doctors report insufficient feedback on errors. A barrier preventing feedback is that individual prescribers often cannot be clearly identified on prescribing documentation.

Aim

To reduce prescribing errors in a UK hospital by improving feedback on prescribing errors.

Interventions

We developed three linked interventions using plan–do–study–act cycles: (1) name stamps for junior doctors who were encouraged to stamp or write their name clearly when prescribing; (2) principles of effective feedback to support pharmacists to provide feedback to doctors on individual prescribing errors and (3) fortnightly prescribing advice emails that addressed a common and/or serious error.

Implementation and evaluation

Interventions were introduced at one hospital site in August 2013 with a second acting as control. Process measures included the percentage of inpatient medication orders for which junior doctors stated their name. Outcome measures were junior doctors' and pharmacists' perceptions of current feedback provision (evaluated using quantitative pre-questionnaires and post-questionnaires and qualitative focus groups) and the prevalence of erroneous medication orders written by junior doctors between August and December 2013.

Results

The percentage of medication orders for which junior doctors stated their name increased from about 10% to 50%. Questionnaire responses revealed a significant improvement in pharmacists' perceptions but no significant change for doctors. Focus group findings suggested increased doctor engagement with safe prescribing. Interrupted time series analysis showed no difference in weekly prescribing error rates between baseline and intervention periods, compared with the control site.

Conclusion

Findings suggest improved experiences around feedback. However, attempts to produce a measurable reduction in prescribing errors are likely to need a multifaceted approach of which feedback should form part.
‘Down-triage’ for children with abnormal vital signs: evaluation of a new triage practice at a paediatric emergency department in Japan
Authors: Takahashi Takuto , Inoue Nobuaki , Shimizu Naoki , Terakawa Toshiro , Goldman Ran D
Published: April 2016

Objective

Assessment of abnormal vital signs in triage is a challenge in the paediatric emergency department (PED), since vital signs may reflect anxiety, fever or pain rather than the clinical deterioration of the child. We aimed to evaluate the efficacy of subjective ‘down-triage’ (change of the initially determined acuity levels) of Japanese Triage and Acuity Scale (JTAS).

Methods

This is a retrospective cohort study of patients in PED up to 15 years of age at a tertiary paediatric medical centre in Japan during a 1-year period. At the end of every JTAS triage process, PED nurses were allowed to ‘down-triage’ acuity levels of well-appearing patients with abnormal HR or RR, which were presumably attributable to fever, crying or being upset. We compared predictive performance of the triage system before and after ‘down-triage’ using admission rate as the primary outcome.

Results

Among 37 961 PED visits during the study period, we analysed 37 219 records. A total of 17 089 patients (45.9%) were ‘down-triaged’ after their initial triage allocation upon arrival. Admission rates after ‘down-triage’ (83%, 33%, 7%, 1% and 3% for levels 1–5, respectively), compared with those of unmodified initial level (16%, 11%, 6%, 2% and 6% for levels 1–5, respectively), had a better apparent relevance with the anticipated admission rates of Canadian Triage and Acuity Scale.

Conclusions

Modification of JTAS through ‘down-triage’ by experienced staff improves prediction of disposition in a PED. Further research is needed to determine an objective protocol for ‘down-triage’ to ensure safe practice in a PED.
Procedural sedation and analgesia in the emergency room of a field hospital after the Nepal earthquake
Authors: Weiser Giora , Ilan Uri , Mendlovic Joseph , Bader Tarif , Shavit Itai
Published: April 2016

Procedural sedation and analgesia (PSA) should be a priority in the emergency care of injured children. This humanistic approach is particularly important in paediatric victims of disaster, because these patients are prone to psychological distress secondary to the traumatic event. Following the Nepal earthquake, an Israeli field hospital (IFH) was deployed in Kathmandu. We report our experience with PSA in the emergency room (ER) of the IFH. 22 children underwent surgery in the operating room and 10 underwent PSA in the ER by paediatric emergency physicians: 6 had wound debridement, 2 had fracture reduction and 2 had laceration repair. All the procedures were successfully completed in the ER and no patient required intubation or admission to the intensive care unit due to an adverse event. The present study is the first report of the practice of paediatric PSA by non-anaesthesiologists in a field hospital.
Study protocol for the Flooring for Injury Prevention (FLIP) Study: a randomised controlled trial in long-term care
Authors: Lachance Chantelle C , Feldman Fabio , Laing Andrew C , Leung Pet Ming , Robinovitch Stephen N , Mackey Dawn C
Published: April 2016

Background

A promising strategy for reducing the incidence and severity of fall-related injuries in long-term care (LTC) is to decrease the ground surface stiffness, and the subsequent forces applied to the body parts at impact, through installation of compliant flooring that does not substantially affect balance or mobility. Definitive evidence of the effects of compliant flooring on fall-related injuries in LTC is lacking. The Flooring for Injury Prevention (FLIP) Study is designed to address this gap.

Methods

The FLIP Study is a 4-year, parallel-group, 2-arm, randomised controlled superiority trial of flooring in 150 resident rooms at a LTC site. The primary objective is to determine whether compliant flooring reduces serious fall-related injuries relative to control flooring. Intervention (2.54 cm SmartCells compliant; 74 rooms) and control (2.54 cm plywood; 76 rooms) floorings were installed over the top of existing concrete floors and covered with identical 2.00 mm vinyl. The primary outcome is serious fall-related injury, defined as any impact-related injury due to a fall in a study room that results in Emergency Department visit or hospital admission. Secondary outcomes include minor fall-related injury, any fall-related injury, falls, number of fallers, fractures, and healthcare utilisation and costs for serious fall-related injuries. Randomisation of study rooms, and residents in rooms, was stratified by residential unit, and flooring assignments were concealed. Outcome ascertainment began September 2013.

Discussion

Results from the FLIP Study will provide evidence about the effects of compliant flooring on fall-related injuries in LTC and will guide development of safer environments for vulnerable older adults.

Trial registration number

NCT01618786.
Patients as story-tellers of healthcare journeys
Authors: Lamprell Klay , Braithwaite Jeffrey
Published: April 2016

There are gaps in our comprehension of patients' subjective experiences as they engage with and transit through the healthcare environments implicated in their treatment trajectories. Patients' stories, unlike patient experience data gathered in questionnaires and surveys, express the deeply personal, narrative nature of the journeys that patients take, creating opportunities for qualitative healthcare research. Yet narrative capabilities and propensities vary with individuals, and are affected by the stresses of illness and treatment. This article extends the growing interest in narrative competence training for both practitioners and patients with the investigation of a story-telling model that could facilitate patients to narrate their experiences of healthcare systems. This model is derived from the literary arts. In fiction and autobiography, the journey arc of the central character is often one in which he or she is compelled to leave the comfort of everyday life and face a series of extraordinary events involving challenge and change which forces the character towards practical, intellectual, psychological and philosophical adjustments that define, by the end of the story, the character's ‘new normal’. This pattern is known as the ‘hero journey’. Its parallels with patients' experiences of healthcare and the way people narrate their stories of illness have long been recognised. We present here a new idea for applying this model as a narrative structure by which patients may construct their stories about being in and moving through the healthcare system.
Mobile internet service for self-management of physical activity in people with rheumatoid arthritis: evaluation of a test version
Authors: Revenäs Åsa , Opava Christina H , Ahlén Henrik , Brusewitz Maria , Pettersson Susanne , Åsenlöf Pernilla
Published: April 2016

Objectives

Life-long adherence to health-enhancing physical activity (PA) is a major challenge for people with rheumatoid arthritis (RA). Our aim was to evaluate the utilisation of and experiences with a RA-specific, mobile internet PA support service, ‘tRAppen’, developed through a co-design process.

Methods

28 participants with RA formed 3 web communities and tested tRAppen for 6 weeks. A mixed-method design was used to combine different types of data. Log data and questionnaire data were analysed quantitatively, while data from telephone interviews were analysed with a directed content analysis.

Results

25 of the 28 participants used tRAppen. Log data indicated that a majority of them registered their PA, sent likes and posted comments to peers, set personal goals and made exercise plans. tRAppen was rated as easy and fun to use, and fairly informative and supportive for PA, and was highly recommended for people with RA. The interview analysis resulted in the following 6 categories describing the utilisation of and experiences with tRAppen: (1) experiences in general, (2) feasibility of features, (3) value as support for PA, (4) enjoyment, (5) ideas for improvements and (6) additional factors.

Conclusions

tRAppen is the first co-designed mobile internet service developed specifically for the self-management of PA in people with RA. The results are promising and indicate that tRAppen may be useful for supporting a physically active lifestyle in a subpopulation at certain risk of poor health. It will now be revised, launched and continuously updated in an iterative process involving its future users.
Climatic and agronomic effects on leaf spots of spring wheat in the western Canadian Prairies
Authors: Fernandez M.R. , Wang H. , Cutforth H. , Lemke R.
Published: April 2016

Leaf spots (LS) of wheat continue to be widespread in western Canada. Most registered cultivars do not have a good level of resistance, thus it is important to evaluate the impact of agronomic practices. This study examined LS severity of spring wheat in a cropping sequence trial under conservation tillage, and compared it to results from two other agronomic trials conducted under different environmental conditions in the same area two decades earlier. In the present study, wheat grown after fallow generally had lower LS severity than wheat grown after another wheat crop, regardless of the sequence, with wheat grown after non-cereals (crop or green manure) having among the lowest disease levels. In most cases there were no differences in disease within phases of each sequence. Grain yield was highest in wheat grown after fallow or green manure than in wheat grown after another wheat, regardless of the sequence. Some of these results were different than those reported from studies conducted before, under conventional or conservation tillage, in particular in regards to disease levels after a fallow year, and the frequency of Pyrenophora tritici-repentis and Phaeosphaeria nodorum. Climatic conditions in the years of the present study (2010–2013) were different than when the previous studies were conducted (1993–1996), especially in regards to temperatures over the previous fall/winter and precipitation in the growing season, which were all higher in the most recent period. How these differences might have affected the survival and reproduction of the LS pathogens, and disease development, are discussed.
Schwartz operators
Authors: Keyl M. , Kiukas J. , Werner R. F.
Published: April 2016

In this paper, we introduce Schwartz operators as a non-commutative analog of Schwartz functions and provide a detailed discussion of their properties. We equip them, in particular, with a number of different (but equivalent) families of seminorms which turns the space of Schwartz operators into a Fréchet space. The study of the topological dual leads to non-commutative tempered distributions which are discussed in detail as well. We show, in particular, that the latter can be identified with a certain class of quadratic forms, therefore making operations like products with bounded (and also some unbounded) operators and quantum harmonic analysis available to objects which are otherwise too singular for being a Hilbert space operator. Finally, we show how the new methods can be applied by studying operator moment problems and convergence properties of fluctuation operators.
Automated Video Detection of Epileptic Convulsion Slowing as a Precursor for Post-Seizure Neuronal Collapse
Authors: Kalitzin Stiliyan N. , Bauer Prisca R. , Lamberts Robert J. , Velis Demetrios N. , Thijs Roland D. , Lopes Da Silva Fernando H.
Published: April 2016

Automated monitoring and alerting for adverse events in people with epilepsy can provide higher security and quality of life for those who suffer from this debilitating condition. Recently, we found a relation between clonic slowing at the end of a convulsive seizure (CS) and the occurrence and duration of a subsequent period of postictal generalized EEG suppression (PGES). Prolonged periods of PGES can be predicted by the amount of progressive increase of interclonic intervals (ICIs) during the seizure. The purpose of the present study is to develop an automated, remote video sensing-based algorithm for real-time detection of significant clonic slowing that can be used to alert for PGES. This may help preventing sudden unexpected death in epilepsy (SUDEP). The technique is based on our previously published optical flow video sequence processing paradigm that was applied for automated detection of major motor seizures. Here, we introduce an integral Radon-like transformation on the time–frequency wavelet spectrum to detect log–linear frequency changes during the seizure. We validate the automated detection and quantification of the ICI increase by comparison to the results from manually processed electroencephalography (EEG) traces as “gold standard”. We studied 48 cases of convulsive seizures for which synchronized EEG-video recordings were available. In most cases, the spectral ridges obtained from Gabor-wavelet transformations of the optical flow group velocities were in close proximity to the ICI traces detected manually from EEG data during the seizure. The quantification of the slowing-down effect measured by the dominant angle in the Radon transformed spectrum was significantly correlated with the exponential ICI increase factors obtained from manual detection. If this effect is validated as a reliable precursor of PGES periods that lead to or increase the probability of SUDEP, the proposed method would provide an efficient alerting device.
Equilibrium and nonequilibrium models on Solomon networks
Authors: Lima F. W. S.
Published: April 2016

We investigate the critical properties of the equilibrium and nonequilibrium systems on Solomon networks. The equilibrium and nonequilibrium systems studied here are the Ising and Majority-vote models, respectively. These systems are simulated by applying the Monte Carlo method. We calculate the critical points, as well as the critical exponents ratio [Formula: see text], [Formula: see text] and [Formula: see text]. We find that both systems present identical exponents on Solomon networks and are of different universality class as the regular two-dimensional ferromagnetic model. Our results are in agreement with the Grinstein criterion for models with up and down symmetry on regular lattices.
Descent Symmetrization of the Dai–Liao Conjugate Gradient Method
Authors: Babaie-Kafaki Saman , Ghanbari Reza
Published: April 2016

Symmetrizing the Dai–Liao (DL) search direction matrix by a rank-one modification, we propose a one-parameter class of nonlinear conjugate gradient (CG) methods which includes the memoryless Broyden–Fletcher–Goldfarb–Shanno (MLBFGS) quasi-Newton updating formula. Then, conducting an eigenvalue analysis, we suggest two choices for the parameter of the proposed class of CG methods which simultaneously guarantee the descent property and well-conditioning of the search direction matrix. A global convergence analysis is made for uniformly convex objective functions. Computational experiments are done on a set of unconstrained optimization test problems of the CUTEr collection. Results of numerical comparisons made by the Dolan–Moré performance profile show that proper choices for the mentioned parameter may lead to promising computational performances.
Synchronization of complex networks coupled by periodically intermittent noise
Authors: Li Shuang , Yan Huiyun , Li Jiaorui
Published: April 2016

Noise is ubiquitous in real systems, so it is important to investigate the effects of noise on the network system. In this paper, the synchronization of complex network coupled by periodically intermittent noise is investigated and a sufficient condition of noise-induced synchronization is obtained analytically via stability theory of stochastic differential equation. The sufficient condition provides a theoretical reference for the analysis of the impact of coupling noise intensity, duration, coupled oscillator number and other parameters on the synchronization behavior. As examples, Rossler-like and Lorenz network systems are presented to verify the theoretical result.
Electron paramagnetic resonance in Cu-doped ZnO
Authors: Buchheit R. , Acosta-Humánez F. , Almanza O.
Published: April 2016

In this work, ZnO and Cu-doped ZnO nanoparticles [Formula: see text], [Formula: see text], with a calcination temperature of 500[Formula: see text]C were synthesized using the sol–gel method. The particles were analyzed using atomic absorption spectroscopy (AAS), X-ray diffraction (XRD) and electron paramagnetic resonance (EPR) at X-band, measurement in a temperature range from 90 K to room temperature. AAS confirmed a good correspondence between the experimental doping concentration and the theoretical value. XRD reveals the presence of ZnO phase in hexagonal wurtzite structure and a nanoparticle size for the samples synthesized. EPR spectroscopy shows the presence of point defects in both samples with [Formula: see text]-values of [Formula: see text] for shallow donors and [Formula: see text] for ionized vacancies. It is important when these materials are required have been used as catalysts, as suggested that it is not necessary prepare them at higher temperature. A simulation of the Cu EPR signal using an anisotropic spin Hamiltonian was performed and showed good coincidence with the experimental spectra. It was shown that Cu[Formula: see text] ions enter interstitial octahedral sites of orthorhombic symmetry in the wurtzite crystal structure. Temperature dependence of the EPR linewidth and signal intensity shows a paramagnetic behavior of the sample in the measurement range. A Néel temperature [Formula: see text] K was determined.
Ballistic thermal transport properties at low temperatures in semiconductor nanowires-based heterojunctions
Authors: Yu Xia , Xie Zhong-Xiang , Liu Jun-Hun , Chen Qiao , Li Ke-Min , Zhang Yong
Published: April 2016

In this paper, we study ballistic thermal transport properties at low temperatures in semiconductor nanowires-based heterojunctions under hard-wall boundary conditions (HWBCs) and stress-free boundary conditions (SFBCs). Here, the numerical calculations for the asymmetric heterojunction (ASHJ) and symmetric heterojunction (SHJ) are done. When SFBCs are employed, the transmission coefficient exhibits different behaviors between ASHJ and SHJ especially at low frequency, but when HWBCs are employed, the transmission coefficient displays similar smooth platforms in both heterojunctions. In low temperature limit, the quantized thermal conductance can be observed in SHJ under SFBCs regardless of the structural details. However, this quantization cannot be observed in ASHJ under SFBCs, and the thermal conductance is strongly sensitive to the transverse width ratio rather than the slant angle. With increasing the transverse width ratio, the thermal conductance in both heterojunctions gradually increases especially, and such the increasing degree is more evident at higher temperatures. A brief analysis of these results is given.
On the Number of Invariant Cones and Existence of Periodic Orbits in 3-dim Discontinuous Piecewise Linear Systems
Authors: Huan Song-Mei , Yang Xiao-Song
Published: April 2016

For a family of discontinuous 3-dim homogeneous piecewise linear dynamical systems with two zones, we investigate the number of invariant cones and the existence of periodic orbits as a spatial relationship between the invariant manifolds of the subsystem changes. By studying the number of real roots of a quadratic equation induced by slopes of half straight lines starting from the origin in required domain, we obtain complete results on the number and stability of invariant cones. Especially, we prove that the maximum number of invariant cones is two, and obtain complete parameter regions on which there exist one or two invariant cones, on which one or two fake cones (corresponding to real roots of the quadratic equation that are not in the required domain) appear and on which an invariant cone will be foliated by periodic orbits.
Exploring Chaos and Entanglement in the Hénon–Heiles System Using Squeezed Coherent States
Authors: Joseph Sijo K. , Sanjuán Miguel A. F.
Published: April 2016

Quantum entanglement in the Hénon–Heiles system is analyzed using the squeezed coherent state. Enhancement of quantum entanglement via squeezing is explored in connection with chaotic and regular dynamics of the system. It is found that the entanglement enhancement via squeezing is implicitly linked to the local structure of the classical phase-space and it shows a clear quantum-classical correspondence. In particular, the entanglement enhancement via squeezing is found to be negligible for a highly chaotic orbit compared to the regular and weakly chaotic orbits, and shows a clear correspondence to the degree of chaos present in the classical initial condition. We believe that these results might be useful to develop efficient strategies to enhance entanglement in quantum systems.
Pro-p completions of groups of cohomological dimension 2
Authors: Kochloukova Dessislava H.
Published: April 2016

We study when an abstract finitely presented group [Formula: see text] of cohomological dimension [Formula: see text] has pro-[Formula: see text] completion [Formula: see text] of cohomological dimension [Formula: see text]. Furthermore, we prove that for a tree hyperbolic limit group [Formula: see text] we have [Formula: see text] and show an example of a hyperbolic limit group [Formula: see text] that is not free and [Formula: see text] is free pro-[Formula: see text]. For a finitely generated residually free group [Formula: see text] that is not a limit group, we show that [Formula: see text] is not free pro-[Formula: see text].
ABOUT THE MULTIFRACTAL NATURE OF CANTOR’S BIJECTION: BOUNDS FOR THE HÖLDER EXPONENT AT ALMOST EVERY IRRATIONAL POINT
Authors: NICOLAY SAMUEL , SIMONS LAURENT
Published: April 2016

In this note, we investigate the regularity of Cantor’s one-to-one mapping between the irrational numbers of the unit interval and the irrational numbers of the unit square. In particular, we explore the fractal nature of this map by showing that its Hölder regularity lies between 0.35 and 0.72 almost everywhere (with respect to the Lebesgue measure).
STRUCTURAL COLOR MODEL BASED ON SURFACE MORPHOLOGY OF MORPHO BUTTERFLY WING SCALE
Authors: HUANG ZHONGJIA , CAI CONGCONG , WANG GANG , ZHANG HUI , HUTTULA MARKO , CAO WEI
Published: April 2016

Color production through structural coloration is created by micrometer and sub-micrometer surface textures which interfere with visible light. The shiny blue of morpho menelaus is a typical example of structural coloring. Modified from morphology of the morpho scale, a structure of regular windows with two side offsets was constructed on glass substrates. Optical properties of the bioinspired structure were studied through numerical simulations of light scattering. Results show that the structure can generate monochromatic light scattering. Wavelength of scattered light is tunable via changing the spacing between window shelves. Compared to original butterfly model, the modified one possesses larger illumination scopes in azimuthal distributions despite being less in polar directions. Present bionic structure is periodically repeated and is easy to fabricate. It is hoped that the computational materials design work can inspire future experimental realizations of such a structure in photonics applications.
TERRACE INDUCED HOMOCHIRAL SELF-ASSEMBLY OF ZINC PHTHALOCYANINEON COPPER (111) SURFACE
Authors: SONG XIN , KONG HUIHUI , LIU LACHENG , LIU XIAOQING , DONG MINGDONG , WANG LI
Published: April 2016

It is still a challenge to find a suitable method to fabricate a well-defined homochiral surface from achiral molecules, and one of the possible methods is to modify surfaces with organic molecular assemblies. Large-area chiral self-assembly nanostructures have been observed at room temperature by depositing ZnPc molecules on a Cu(111) surface. The growth process has been investigated. ZnPc molecules get adsorbed first at the terrace steps, and then extend over the lower terrace until the whole terrace is covered with ZnPc molecules; such growth process would be stopped when the self-assembly nanostructure run into a decorated upper terrace step edge. We found that the terrace steps with specific directions with respect to the close-packed directions of the substrate can induce homochiral self-assembly on the lower terraces. So we can propose a possible way to fabricate a well-defined homochiral surface from achiral organic molecules.
Effect of Weather on Agricultural Futures Markets on the Basis of DCCA Cross-Correlation Coefficient Analysis
Authors: Cao Guangxi , He Cuiting , Xu Wei
Published: April 2016

This study investigates the correlation between weather and agricultural futures markets on the basis of detrended cross-correlation analysis (DCCA) cross-correlation coefficients and [Formula: see text]-dependent cross-correlation coefficients. In addition, detrended fluctuation analysis (DFA) is used to measure extreme weather and thus analyze further the effect of this condition on agricultural futures markets. Cross-correlation exists between weather and agricultural futures markets on certain time scales. There are some correlations between temperature and soybean return associated with medium amplitudes. Under extreme weather conditions, weather exerts different influences on different agricultural products; for instance, soybean return is greatly influenced by temperature, and weather variables exhibit no effect on corn return. Based on the detrending moving-average cross-correlation analysis (DMCA) coefficient and DFA regression results are similar to that of DCCA coefficient.
Quasi-Baer and biregular generalized matrix rings
Authors: Birkenmeier Gary F. , Davis Donald D.
Published: April 2016

Generalized matrix rings are ubiquitous in algebra and have relevant applications to analysis. A ring is quasi-Baer (respectively, right p.q.-Baer) in case the right annihilator of any ideal (respectively, principal ideal) is generated by an idempotent. A ring is called biregular if every principal ideal is generated by a central idempotent. In this paper, we identify the ideals and principal ideals, the annihilators of ideals, and the central and semi-central idempotents of a generalized [Formula: see text] matrix ring. We characterize the generalized matrix rings that are quasi-Baer, right p.q.-Baer, prime, and biregular. We provide examples to illustrate these concepts.