Two-channel Kondo physics due to As vacancies in the layered compound ZrAs1.58Se0.39

We address the origin of the magnetic-field independent -|A| T^{1/2} term observed in the low-temperature resistivity of several As-based metallic systems of the PbFCl structure type. For the layered compound ZrAs_{1.58}Se_{0.39}, we show that vacancies in the square nets of As give rise to the low-temperature transport anomaly over a wide temperature regime of almost two decades in temperature. This low-temperature behavior is in line with the non-magnetic version of the two-channel Kondo effect, whose origin we ascribe to a dynamic Jahn-Teller effect operating at the vacancy-carrying As layer with a C_4 symmetry. The pair-breaking nature of the dynamical defects in the square nets of As explains the low superconducting transition temperature T_{\rm{c}}\approx 0.14 K of ZrAs_{1.58}Se_{0.39}, as compared to the free-of-vacancies homologue ZrP_{1.54}S_{0.46} (T_{\rm{c}}\approx 3.7 K). Our findings should be relevant to a wide class of metals with disordered pnictogen layers.Comment: 17 pages, 8 figures; submitte

Managing gender, age and disability diversity in an organization on the example of a robotics company

Purpose: the aim of this article is to present the role of diversity management in the organization’s development process by indicating the benefits and threats of implementing this concept. Method: a research method used was a case study. Also, good practices in the field of diversity management, used by “X” company operating in the robotics industry, were analyzed. The company’s diversity management strategy was examined as well, and it was found that an inclusive culture is an important determinant of its business success. The results of the study: the idea of diversity management is to build an open and inclusive work environment, the space of mutual respect in which employees have the opportunity to fulfill their own potential for the success of the entire company. Theoretical implications: an appropriate diversity management strategy could help the organization to identify areas of diversity and will result in higher staff efficiency. Diversity management is an important element of corporate social responsibility. Практична цінність дослідження: Diversity, which refers to all differences among people (ethnic, cultural, linguistic, ideological), is now more important than ever. Just as biodiversity gives the ecosystem strength and resilience, employee diversity contributes to building an integral work environment, and thereby it strengthens the organization. Companies with greater diversity are more creative, dynamic, flexible, and they understand the needs of the market better. Value: this article examines whether employee diversity management has a positive impact on the company’s development, and whether it generates innovation, efficiency, and better economic results for the organization. Papertype: theoretical

Small vessel coronary artery disease: How small can we go with myocardial revascularization?

The issue of small coronary artery atherosclerosis represents an intriguing aspect of coronary artery disease, which is related with higher rates of peri- and post-procedural complications and impaired long-term outcome. This problem is further complicated by the unclear definition of small coronary vessel. Recent randomized controlled trials have provided new data on possible novel interventional treatment of small coronary vessels with drug-coated balloons instead of traditional new-generation drug-eluting stent implantation. Also, the conservative management represents a therapeutic option in light of the results of the recent ISCHEMIA trial. The current article provides an overview of the most appropriate definition, interventional management, and prognosis of small coronary artery atherosclerosis

Effectiveness and safety of mechanical thrombectomy for acute ischaemic stroke in Latin American countries: A systematic review

YesTo describe the use, effectiveness, and safety outcomes of mechanical thrombectomy (MT) for acute ischemic stroke (AIS) in Latin American countries. Studies reporting MT outcomes for AIS in Latin America were identified in CINAHL, MEDLINE, Web of Science, SciELO, EMBASE, and LILACS databases. Synthesis was conducted according to effectiveness (recanalization rates) and safety measures (mortality and functional independence at 90 days). Seventeen studies were included, mainly from public and university hospitals. MT utilization varied from 2.6% to 50.1%, while successful recanalization ranged from 63% to 95%. Functional independence 90 days after stroke (a modified Rankin scale score of 0 to 2) was achieved in less than 40% across most studies. Mortality rates were below 30%; studies with posterior circulation strokes reported higher mortality rates. The randomized trial reported better health outcomes for functional independence among patients in the MT group (OR 2.28; 95% CI, 1.41 - 3.69), favoring MT over standard care. The included studies had great methodological heterogeneity due to differences in study design, the MT time window, and stroke location. The only randomized trial showed improved functional independence and lower mortality rates with MT than with standard care. The rest of the studies reported similar findings to available literature. Efforts to improve stroke care are reflected in improved patient outcomes in the region. Future studies should consider standard time window criteria and reduce the risk of bias by including representative samples and comparison groups

Insights into the regulation of DMSP synthesis in the diatom Thalassiosira pseudonana through APR activity, proteomics and gene expression analyses on cells acclimating to changes in salinity, light and nitrogen

Despite the importance of dimethylsulphoniopropionate (DMSP) in the global sulphur cycle and climate regulation, the biological pathways underpinning its synthesis in marine phytoplankton remain poorly understood. The intracellular concentration of DMSP increases with increased salinity, increased light intensity and nitrogen starvation in the diatom Thalassiosira pseudonana. We used these conditions to investigate DMSP synthesis at the cellular level via analysis of enzyme activity, gene expression and proteome comparison. The activity of the key sulphur assimilatory enzyme, adenosine 5′- phosphosulphate reductase was not coordinated with increasing intracellular DMSP concentration. Under all three treatments coordination in the expression of sulphur assimilation genes was limited to increases in sulphite reductase transcripts. Similarly, proteomic 2D gel analysis only revealed an increase in phosphoenolpyruvate carboxylase following increases in DMSP concentration. Our findings suggest that increased sulphur assimilation might not be required for increased DMSP synthesis, instead the availability of carbon and nitrogen substrates may be important in the regulation of this pathway. This contrasts with the regulation of sulphur metabolism in higher plants, which generally involves upregulation of several sulphur assimilatory enzymes. In T. pseudonana changes relating to sulphur metabolism were specific to the individual treatments and, given that little coordination was seen in transcript and protein responses across the three growth conditions, different patterns of regulation might be responsible for the increase in DMSP concentration seen under each treatment

Clinical Study Complex Assessment of the Incidence and Risk Factors of Delirium in a Large Cohort of Cardiac Surgery Patients: A Single-Center 6-Year Experience

Background. Previous reports provided inconsistent data on the occurrence of postoperative delirium and emphasized its considerable impact on outcome. This study sought to evaluate the incidence and predictors of delirium, together with its relation to cerebral ischemia in a large cohort of cardiac surgery patients in a tertiary high-volume center. Methods and Results. Consecutive patients (n = 8792) were prospectively enrolled from 2003 to 2008. Exclusion criteria were history of psychiatric disorders, use of psychoactive drugs, alcohol abuse, and data incompleteness. Finally, 5781 patients were analyzed in terms of 100 perioperative patient-specific and treatment variables. The incidence of postoperative delirium (DSM IV criteria) was 4.1% and it coexisted with cerebral ischemia in 1.1% of patients. In bivariate analysis, 49 variables were significantly linked to postoperative delirium. Multivariate analysis confirmed that delirium was independently associated with postoperative stroke (logistic odds ratio (logOR) = 2.862, P = 0.004), any blood transfusions (logOR = 4.178, < 0.0001), age > 65 years (logOR = 2.417, P = 0.002), carotid artery stenosis (logOR = 2.15, P = 0.01), urgent/emergent surgery (logOR = 1.982, P = 0.02), fasting glucose level, intraoperative oxygen partial pressure fluctuations, and hematocrit. Area under ROC curve for the model was 0.8933. Conclusions. Early identification of nonpsychiatric perioperative determinants of delirium facilitates its diagnosis and might help develop preventive strategies to improve long-term outcome after cardiac surgery procedures

Distinguishing Asthma Phenotypes Using Machine Learning Approaches.

Asthma is not a single disease, but an umbrella term for a number of distinct diseases, each of which are caused by a distinct underlying pathophysiological mechanism. These discrete disease entities are often labelled as asthma endotypes. The discovery of different asthma subtypes has moved from subjective approaches in which putative phenotypes are assigned by experts to data-driven ones which incorporate machine learning. This review focuses on the methodological developments of one such machine learning technique-latent class analysis-and how it has contributed to distinguishing asthma and wheezing subtypes in childhood. It also gives a clinical perspective, presenting the findings of studies from the past 5 years that used this approach. The identification of true asthma endotypes may be a crucial step towards understanding their distinct pathophysiological mechanisms, which could ultimately lead to more precise prevention strategies, identification of novel therapeutic targets and the development of effective personalized therapies

Search for anomalous t t-bar production in the highly-boosted all-hadronic final state

A search is presented for a massive particle, generically referred to as a Z', decaying into a t t-bar pair. The search focuses on Z' resonances that are sufficiently massive to produce highly Lorentz-boosted top quarks, which yield collimated decay products that are partially or fully merged into single jets. The analysis uses new methods to analyze jet substructure, providing suppression of the non-top multijet backgrounds. The analysis is based on a data sample of proton-proton collisions at a center-of-mass energy of 7 TeV, corresponding to an integrated luminosity of 5 inverse femtobarns. Upper limits in the range of 1 pb are set on the product of the production cross section and branching fraction for a topcolor Z' modeled for several widths, as well as for a Randall--Sundrum Kaluza--Klein gluon. In addition, the results constrain any enhancement in t t-bar production beyond expectations of the standard model for t t-bar invariant masses larger than 1 TeV.Comment: Submitted to the Journal of High Energy Physics; this version includes a minor typo correction that will be submitted as an erratu

Search for the standard model Higgs boson in the H to ZZ to 2l 2nu channel in pp collisions at sqrt(s) = 7 TeV

A search for the standard model Higgs boson in the H to ZZ to 2l 2nu decay channel, where l = e or mu, in pp collisions at a center-of-mass energy of 7 TeV is presented. The data were collected at the LHC, with the CMS detector, and correspond to an integrated luminosity of 4.6 inverse femtobarns. No significant excess is observed above the background expectation, and upper limits are set on the Higgs boson production cross section. The presence of the standard model Higgs boson with a mass in the 270-440 GeV range is excluded at 95% confidence level.Comment: Submitted to JHE