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Coronavirus disease 2019 (COVID-19) pandemic disorganised healthcare systems and has caused a reduction in the number of hospitalizations and procedures. Cardiac implantable electronic device (CIED) procedure rates and clinical characteristics of their recipients were compared in corresponding weeks of 2019 and 2020 were analyzed.The database of the National Health Fund (NHF) in Poland was retrospectively analyzed. 3206 patients who underwent CIED implantation in the Silesia - a region in Southern Poland comprising an adult population of 3.8 million between 12th and 31st week of 2020. Patients were classified into groups: the recipient of an implantable cardioverter-defibrillator or cardiac resynchronization therapy group (ICD/CRT) or pacemaker group (PM).During the pandemic a reduction of 39.38% of implantations was observed compared to the same period in 2019 (1210 vs. 1996 patients) and had impacted both groups. Two phases lasting 10 weeks each could be distinguished: total lockdown (maximal reduction) and the recovery phase with growing numbers of procedures. Patient baseline characteristics (sex, age, comorbidities) who were implanted during the COVID-19 pandemic did not differ from the 2019 period. The rate of peri-procedural mortality was also similar.During COVID-19 pandemic period a reduction in CIED implantations of all types was observed. Despite the decreased number of performed CIED implants, no differences in baseline patient characteristics were observed.

Heart failure (HF) remains a disease with a poor prognosis. Telemonitoring is a medical service aimed at remote monitoring of patients.The study aimed to identify the clinical relevance of non-invasive telemonitoring devices in HF patients.Sixty patients aged 66.1 (11) years, with left ventricular ejection fraction (LVEF) 26.3 (6.8)% underwent cardiac resynchronization therapy (CRT) implantation. They were randomly allocated to the control (standard medical care) or study (standard medical care + telemonitoring device) groups. During the follow-up (24 months), the patients in the study group provided body mass and blood pressure, along with electrocardiogram on a daily basis. The data were transferred to themonitoring center and consulted with a cardiologist. Transthoracic echocardiography and a 6-minute walk test were performed before and 24 months after CRT implantation.During the two-year observation, the composite endpoint (death or HF hospitalization) occurred in 21 patients, more often in the control group (46.8% vs. 21.4%; P = 0.026). Inunivariate analysis: the use of telemetry (hazard ratio [HR], 0.2; 95% confidence interval [CI], 0.07-0.7; P=0.004), thepresence of coronary heart disease (HR, 41.4; 95% CI, 3.1-567.7; P=0.005), hypertension (HR, 0.24; 95% CI, 0.07-0.90; P = 0.035), and patient's body mass (HR, 0.36; 95% CI, 0.14-0.92; P = 0.03) were related to the occurrence of the composite endpoint.The use of a telemonitoring device in CRT recipients improved theprognosis in2-year observation and contributed to the reduction of HF hospitalization.

A retrospective analysis of 60 patients with hybrid ICD systems: Boston Scientific device paired with non-Boston leads. In 10 (17%) patients transient, out-of-range peaks of ventricular pace impedance trend were observed. Probable cause is header-lead interaction incompatibility. This matter is known mainly for pacemakers systems but not for ICDs. Investigation this issue is crucial because consequences in ICD systems are unpredictable and risk might be higher than in pacing systems. This article is protected by copyright. All rights reserved.

Genetic factors can influence the risk of coronary artery disease (CAD) and the survival of patients. Our previous research led to the identification of genetic variants predisposing to CAD in the Polish population. Since many of them affect the clinical phenotype of the disease, the aim of this study was searching for genetic factors potentially influencing survival in patients with CAD. The study included 276 patients hospitalized due to coronary artery disease. The database of medical history and genotypic results of 29 polymorphisms were used. The endpoint was defined as death from cardiovascular causes. Survival was defined as the period from angiographic confirmation of CAD to death from cardiovascular causes. Three of all the analyzed genes were associated with survival. In the case of the

Background: The present study aimed to determine whether the polymorphisms of the 11q23.3 locus affect the risk and mortality of coronary artery disease in 5-year and 10-year observations. Methods: The study group consisted of 519 subjects: 276 patients with CAD and 243 blood donors as controls. The genotyping of polymorphisms (rs10750097, rs3741298, and rs1729410) was performed using the TaqMan-PCR method. Survival was defined as the period from the angiographic confirmation of CAD to cardiovascular death, and the endpoint was defined as death from cardiovascular causes. Results: The G allele of the rs1729410 polymorphism increased the risk of CAD (OR = 1.55, p = 0.04) and showed a synergistic correlation with overweight/obesity (additive synergy index (SI) = 11.01, p < 0.001). The carriers of the GG genotype and over-normative LDL levels increased the risk of CAD by over 12-fold higher than expected (multiplicative synergy index (SIM) = 12.34, p < 0.001). In the case of the rs10750097 variant, an effect on mortality was shown in both 5-year and 10-year periods. Conclusion: The results revealed that the rs1729410 polymorphism increases the risk of CAD in synergy with traditional risk factors, and the rs10750097 polymorphism of the 11q23.3 locus affects the risk of death in patients with CAD.

Objective: Patients with anorexia nervosa (AN) are at increased risk of ventricular arrhythmias, which are considered to be associated with QT interval prolongation. The aims of this study was to analyse the QT interval in patients with AN considering the potential impact of pharmacotherapy and to verify various QT correction formulas. Method: Fifty-six patients hospitalized with AN (average age: 22.8±5.6 years; F/M: 54/2, mean BMI=13.6±2.6 kg/m2) were enrolled to analysis: Group non-D (n=44; 78,6%) included patients, who did not use drugs that prolong the QT interval, group D (n=12; 21,4%) included patients, who were treated with such drugs. QT intervals were measured in a 12-lead ECG and corrected using the four formulas: Bazett, Fridericia, Framingham and Hodges. Results: Mean heart rate (HR) was similar in both groups (61±16.3 bpm in group D vs 63.1±18.7 bpm in non-D, p > 0.05). Pathological bradycardia (HR < 50 bpm) was present in 5 patients (41.7%) in group D and in 13 patients (29.5%) in group non-D. QTc interval corrected with Framingham formula was longer in Group-D (459±81ms) vs non D-group (413±33ms) p=0.04. QT interval corrected with Bazett and Hodges formulas was significantly dependent on HR (R= -0.29, p=0.03 and R= -0.42, p=0.001, respectively). Influence of HR on results of Fridericia and Framingham formulas was not significant (R = -0.22, p=0.1 and R = -0.11, p=0.4). Conclussions: Information about pharmacotherapy in AN patients is key for QTc assessment. Choice of correction formula has impact on the QTc. QTc obtained using Framingham and Fridericia formulas were the least dependent on heart rate.

This research is intended to compare degradation processes in light-cured (dimeth)acrylate-type polymer/filler dental composites affected to aging in dry-air and water-immersed mode. The positron annihilation lifetime (PAL) spectroscopy has been employed to study changes in atomic-deficient structure in these composites under aging. Under light-curing polymerization initiating crosslinking of monomer chains, fragmentation of free-volume holes in resin matrix dominates over enhanced fraction of trapped positrons, since filler–particles assemblies get to be more tightly covered by surrounding polymer causing disappearing of interfacial voids at the filler–polymer surface. Therefore, the PAL spectra-transforming trend in light-cured composites obeys inverse positron-to-Ps trapping conversion. In contrast, the PAL spectra-transforming trend in these restoratives under aging obeys direct Ps-to-positron trapping conversion. After dry-air aging, the observed changes in the density of annihilation sites are ascribed to a strong agglomeration of Ps-decay holes in polymer sub-system accompanied by weaker agglomeration and appearance of positron traps in filler–polymer sub-system. Under the water aging, the agglomeration of Ps-decaying holes in the polymer sub-system is suppressed due to absorbed water molecules, this effect being slightly revealed at lower polymerization. New positron traps are observed at the filler–polymer interfaces in all light-cured composites. The agglomerated Ps-decay holes in a polymer matrix and positron traps inside filler–particles assemblies and filler–polymer interfaces of artificially aged composites cause their progressive microcracking.

The aim of the study was: (1) to verify the hypothesis that left ventricular global longitudinal strain (LVGLS) may be of additive prognostic value in prediction CRT response and (2) to obtain such a LVGLS value that in the best optimal way enables to characterize potential CRT responders. Forty-nine HF patients (age 66.5 ± 10 years, LVEF 24.9 ± 6.4%, LBBB 71.4%, 57.1% ischemic aetiology of HF) underwent CRT implantation. Transthoracic echocardiography was performed prior to and 15 ± 7 months after CRT implantation. Speckle-tracking echocardiography was performed to assess longitudinal left ventricular function as LVGLS. The response to CRT was defined as a ≥ 15% reduction in the left ventricular end-systolic volume (∆LVESV). Thirty-six (73.5%) patients responded to CRT. There was no linear correlation between baseline LVGLS and ∆LVESV (r = 0.09;p = 0.56). The patients were divided according to the percentile of baseline LVGLS: above 80th percentile; between 80 and 40th percentile; below 40th percentile. Two peripheral groups (above 80th and below 40th percentile) formed “peripheral LVGLS” and the middle group was called “mid-range LVGLS”. The absolute LVGLS cutoff values were − 6.07% (40th percentile) and − 8.67% (80th percentile). For the group of 20 (40.8%) “mid-range LVGLS” patients mean ΔLVESV was 33.3 ± 16.9% while for “peripheral LVGLS” ΔLVESV was 16.2 ± 18.8% (p p = 0.015). Baseline LVGLS may have a potential prognostic value in prediction CRT response with relationship of inverted J-shaped pattern. “Mid-range LVGLS” values should help to select CRT responders, especially in non-ischemic HF etiology patients.

Background MicroRNAs (miRNAs) are a class of endogenous noncoding RNAs that play a pivotal role in the regulation of plant development and responses to the surrounding environment. Despite the efforts made to elucidate their function in the adaptation of plants to many abiotic and biotic stresses, their role in high light (HL) stress is still vague. HL stress often arises upon plant exposure to full sunlight. Subsequent changes in nuclear gene expression are triggered by chloroplast-derived retrograde signals. Results In this study, we show that HL is involved in miRNA-dependent regulation in Arabidopsis thaliana rosettes. Microtranscriptomic screening revealed a limited number of miRNAs reacting to HL. To explain the miRNA regulation mechanisms at the different biogenesis stages, chemical and genetic approaches were applied. First, we tested the possible role of plastoquinone (PQ) redox changes using photosynthetic electron transport chain inhibitors. The results suggest that increased primary transcript abundance (pri-miRNAs) of HL-regulated miRNAs is dependent on signals upstream of PQ. This indicates that such signals may originate from photosystem II, which is the main singlet oxygen (1O2) source. Nevertheless, no changes in pri-miRNA expression upon a dark–light shift in the conditional fluorescent (flu) mutant producing 1O2 were observed when compared to wild-type plants. Thus, we explored the 1O2 signaling pathway, which is initiated independently in HL and is related to β-carotene oxidation and production of volatile derivatives, such as β-cyclocitral (β-CC). Pri-miRNA induction by β-CC, which is a component of this 1O2 pathway, as well as an altered response in the methylene blue sensitivity 1 (mbs1) mutant support the role of 1O2 signaling in miRNA regulation. Conclusions We show that light stress triggers changes in miRNA expression. This stress response may be regulated by reactive oxygen species (ROS)-related signaling. In conclusion, our results link ROS action to miRNA biogenesis, suggesting its contribution to inconsistent pri- and mature miRNA dynamics.

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Scant data exist on long-term outcomes, including death, in patients with complica-tions related to transvenous lead extractions (TLE).We sought to characterize the population and examine the outcomes including risk factors for in-hospital complications and 12-month mortality and morbidity related to the complications in a large administrative database of patients undergoing TLE.From the database of patients hospitalized for cardiovascular diseases and included in the Silesian Cardiovascular Database (SILCARD) registry, we selected the admissions of those who underwent TLE according to the appropriate ICD-9 codes. The patients were divided into two groups based on whether they did or did not manifest any complications during their hospitalization for the TLE procedure. Between 2007 and 2019, we found a total of 835 patients who underwent TLE. TLE-related complications occurred in 56 patients (6.7%) of the Complications-Yes group while no complications were recorded in 779 (93.3%) patients of the Complications-No group. A significant difference in the rate of all-cause mortality (23.9% vs. 6.5%; P0.001) and major adverse cardiac events (MACE) (58.7% vs. 39.4%; P = 0.01) between the Complications-Yes and Complications-No groups were recorded. Multivariable analysis of the entire study population revealed that prior dialysis, chronic kidney disease, and ventricular tachycardia were independent factors of a higher risk of TLE-related in-hospital complications. Multivariable analysis of the patients discharged from the hospital after the TLE procedure showed that TLE-related complications, a history of heart failure, and older age independently affected 12-month mortality.The presence of TLE-related in-hospital complications increased 12-month mortality.

Introdução: Angiostrongylus vasorum é um nematoide parasito de canídeos domésticos e silvestres, cuja forma adulta pode ser encontrada no ventrículo direito, artérias pulmonares e ramificações. O ciclo do parasito é do tipo heteróxeno, seus hospedeiros definitivos são os canídeos e seus hospedeiros intermediários são moluscos terrestres e aquáticos que se infectam pela ingestão de larvas de primeiro estádio. Os canídeos podem ser infectados através da ingestão de hospedeiros paratênicos como anfíbios. Os sinais clínicos apresentados são: apatia, náusea, vômito, tosse, perda de peso, anorexia, ascite, menor tolerância a atividade física, dispneia intensa e dor abdominal. O diagnóstico clínico é feito através de testes laboratoriais juntamente com os sinais clínicos apresentados. No diagnóstico diferencial os principais achados são bronquite crônica e asma e pode ser utilizado os exames radiológicos, ecocardiográficos e eletrocardiográficos para o diagnóstico. Objetivo: relatar o caso clínico de um canino doméstico acometido por Angiostrongilose. Materiais e Métodos: revisão do prontuário, entrevista com tutor, registro fotográfico dos métodos diagnósticos, aos quais o paciente foi submetido e revisão da literatura. Resultados: as ocorrências de angiostrongilose na clínica médica são muito importantes para o conhecimento e no cotidiano do médico veterinário, além da contribuição para as estratégias adotadas para o diagnóstico e tratamento das doenças. A sintomatologia cardiorrespiratória pode ser justificada pela infiltração de células inflamatórias e broncopneumonia, resultantes da deposição de ovos e migração das larvas pela árvore brônquica do hospedeiro, nos achados radiográficos relacionados com o caso foi diagnosticado a broncopneumonia, e assim direcionado o diagnóstico. Conclusão: os sintomas de angiostrongilose canina pode ser confundida facilmente com outras enfermidades. Exames laboratoriais e de imagens são essenciais para o diagnóstico de angiostrongilose uma vez que sem eles os sinais clínicos apresentados são inconclusivos ao diagnóstico final.

The Steiner tree problem (STP) is a classical NP-hard combinatorial optimization problem with applications in computational biology and network wiring. The objective of this problem is to find a minimum cost subgraph of a given undirected graph G with edge costs, that spans a subset of vertices called terminals. We present currently used linear programming formulations of the problem based on two different approaches—the bidirected cut relaxation (BCR) and the hypergraphic formulations (HYP), the former offering better computational performance, and the latter better bounds on the integrality gap. As our contribution, we propose a new hierarchy of path-based extended formulations for STP.We show that this hierarchy provides better integrality gaps on graph instances used to define the worst-case lower bounds on the integrality gap for both BCR and HYP. We prove that each consecutive level of our hierarchy is at least as strong as the previous one. Additionally, we also present numerical results showing that several difficult STP instances can be solved to integer optimality by using this hierarchy. Our approach can be adapted to variants of STP or applied to hypergraphic formulations for further potential improvement on the integrality gap bounds, in exchange for additional computational effort.

This paper presents studies on the impact of the erbium ions Er3+ on the properties of magneto - optical of the tellurite glasses Magneto-optical properties were investigated based on measurements of the Faraday effect and magnetic susceptibility as well as optical properties of the glasses, i.e. transmission in the visible range. The tests were carried out for clean glass matrices synthesized using various modifiers and glasses additionally doped with erbium ions Er3+. The aim of doped with ions of the paramagnetic element from the lanthanide group was to try to obtain higher Verdet constant values in the examined materials. The dominant type of magnetic ordering was determined on the basis of measurements of the permanent magnetic susceptibility using a vibration magnetometer. The obtained results indicate the paramagnetic nature of the magnetic order in the examined glasses. Glass doped with paramagnetic ions Er3+ resulted in the increase of their magnetic susceptibility, which suggests the possibility of observing better magneto-optical properties. The magneto-optical properties of tellurite glasses were determined based on measurements of the Faraday effect and calculation of the Verdet constant for different wavelengths of polarized light. The obtained results confirm the improvement of the magneto-optical properties of the examined glasses under the influence of doped with erbium ions. The obtained optical parameters are interesting from the point of view of the design of optoelectronic systems. The results of transmission tests showed high permeability of the examined tellurite glasses. The presented results may be important for the development of new materials based on tellurite glasses for applications in optoelectronic devices.

Introduction. The pharmacological treatment of ventricular arrhythmias (VA) has significant limitations. Ranolazine is a relatively new drug with documented antianginal and anti-ischaemic mechanisms and where preclinical data provides evidence of additional antiarrhythmic properties. The aim of this article was to evaluate the safety and efficacy of ranolazine in patients with recurrent antiarrhythmic therapy-refractory VA. Material and methods. This prospective evaluation included 30 patients (pts) (male/female: 26/4; mean age: 65 ± 10 years; coronary artery disease/dilated cardiomyopathy: 20/10; New York Heart Association class I/II/III/IV: 2/14/12/2, left ventricular ejection fraction: 27 ± 10%; implantable cardioverter-defibrillator (ICD): 15 pts, implantable cardioverter- -defibrillator with cardiac resynchronisation therapy (CRT-D): 14 pts with recurrent significant VA [ventricular fibrillation, sustained ventricular tachycardia (VT) and/or non-sustained VT, multiple ventricular premature complexes > 1,000/ /day, biventricular stimulation (BiV) i.e. pharmacotherapy, coronary revascularisation, and percutaneous ablation, had proved ineffective. The severity of the arrhythmia was assessed by 24-hour electrocardiographic (ECG) Holter monitoring and in ICD/CRT-D memory recording. The patients received, in addition to the standard pharmacotherapy (amiodarone: 18 pts, beta-blocker: 26 pts) ranolazine 375 mg twice daily for three months. Baseline data was compared to the data obtained after the three months of ranolazine treatment. Results. We observed a significant reduction of total ventricular extrasystoles determined by ECG Holter monitoring (median: 1,737 vs 1,260, p = 0.04). Similarly, significant VA in ICD/CRT-D memory recording was diminished (67.7 vs 35.5%, p = 0.03). The number of ICD interventions in terms of both antitachycardia pacing (9 pts vs 2 pts, p = 0.01), and shock delivery (8 pts vs 2 pts, p = 0.01), was lower after the three-month observation. The therapy was ineffective for nine (29%) patients — two were hospitalised during the three-month follow-up because of recurrent arrhythmia and in seven pts there was no noticeable reduction in the amount of VA. Adverse effects, in the form of gastrointestinal symptoms (diarrhoea: two, constipation: one), occurred in three (10%) patients. Conclusions. Authors observed no significant QT prolongation in any patient. There were no differences between the baseline and the post-ranolazine patient clinical characteristics. Ranolazine seems to be a safe and effective second- line therapy in the reduction of VA and ICD interventions in patients with recurrent antiarrhythmic therapy-refractory events.

Triggered by the increasing number of renewable energy sources, the German electricity grid is undergoing a fundamental change from mono to bidirectional power flow. This paradigm shift confronts grid operators with new problems but also new opportunities. In this chapter we point out some of these problems arising on different layers of the grid hierarchy and sketch mathematical methods to handle them. While the transmission system operator’s main concern is stability and security of the system in case of contingencies, the distribution system operator aims to exploit inherent flexibilities. We identify possible interconnections among the layers to make the flexibility from the distribution grid available within the whole network. Our presented approaches include: the distributed control of energy storage devices on a residential level; transient stability analysis via a new set-based approach; a new clustering-based model-order reduction technique; and a modeling framework for the power flow problem on the transmission level which incorporates new grid technologies.

Background: Implantable cardioverter-defibrillator (ICD) therapy has been proven effective in the prevention of sudden cardiac death, but data on outcomes of ICD therapy in the young and otherwise healthy patients with long QT syndrome (LQTS) are limited. Aim: We sought to collect data on appropriate and inappropriate ICD discharges, risk factors, and ICD-related complications. Methods: All LQTS patients implanted with an ICD in 14 centres were investigated. Demographic, clinical, and ICD therapy data were collected. Results: The study included 67 patients (88% female). Median age at ICD implantation was 31 years (12–77 years). ICD indication was based on resuscitated cardiac arrest in 46 patients, syncope in 18 patients, and malignant family history in three patients. During a median follow-up of 48 months, 39 (58%) patients received one or more ICD therapies. Time to first appropriate discharge was up to 55 months. Inappropriate therapies were triggered by fast sinus rhythm, atrial fibrillation, and T-wave oversensing. No predictors of inappropriate shocks were identified. Risk factors for appropriate ICD therapy were: (1) recurrent syncope despite b-blocker treatment before ICD implantation, (2) pacemaker therapy before ICD implantation, (3) single-chamber ICD, and (4) noncompliance to b-blockers. In 38 (57%) patients, at least one complication occurred. Conclusions: ICD therapy is effective in nearly half the patient population; however, the rates of early and late complica­tions are high. Although the number of unnecessary ICD shocks and reimplantation procedures may be lowered by modern programming and increased longevity of newer ICD generators, other adverse events are less likely to be reduced.

The materials under investigation were the tellurite glasses. Basic glasses and glasses doped with erbium Er3+ ions were examined. The positron lifetime measurement method PALS (Positron Annihilation Lifetime Spectroscopy) and the Raman spectroscopy were applied in order to analyse their structural properties. The proposed PALS method allows to identify structural defects in amorphous materials (glasses, ceramics and polymers) that are difficult to detect with the use of other traditional measuring methods. The conducted studies revealed two positron lifetime components τ1 and τ2. On the basis of the two-state model, positron capture parameters were calculated, which allowed to draw conclusions concerning the nature and degree of defects of the examined tellurite glasses. Application of the Raman spectroscopy resulted in assessment of the effect of Er3+ on the structure of the examined material.

Silicone oil is the one of the artificial materials used in vitreoretinal surgery for retinal detachment treatment. Since the silicone oil is sometimes applied along with intraocular lens (IOL) implantation the direct influence of silicone oil on the artificial implant should be taken into account. Presented study was performed in order to determine the time-dependent impact of silicone oil on hydrogel based ophthalmic materials. Two kinds of IOLs based on hydroxyethyl 2-methacrylate (HEMA) hydrogel material were immersed in silicone oil based on linear poly(dimethylsiloxane) (PDMS). Incubation in oil medium was performed in 37 °C for 1, 3 and 6 months. After appropriate period of the incubation samples were examined by means of FTIR-ATR method as the technique of surface study as well as Positron Annihilation Lifetime Spectroscopy (PALS) as the method of internal structure investigation. Results obtained during the study revealed that silicone oil is not capable to penetrate the internal structure of investigated materials and its impact has come down to interaction with the samples surfaces only.

Introduction The aim of our study was to determine the risk factors for electrical storm (ES) and to assess the impact of ES on the long-term prognosis in patients after myocardial infarction (MI) with an implantable cardioverter-defibrillator (ICD) for secondary prevention of sudden cardiac death (SCD). Material and methods We retrospectively analyzed 416 patients with coronary artery disease after MI who had an implanted ICD for secondary prevention of SCD. Fifty (12%) patients had one or more incidents of an electrical storm – the ES (+) group. We matched the reference group of 47 patients from 366 ES (–) patients. Results We analyzed 3,408 episodes of ventricular arrhythmias: 3,148 ventricular tachyarrhythmic episodes in the ES (+) group (including 187 episodes of ES) and 260 in the ES (–) group. Multivariate logistic regression showed that inferior wall MI (RR = 3.98, 95% CI: 1.52–10.41) and the absence of coronary revascularization (RR = 2.92, 95% CI: 1.18–7.21) were independent predictors of ES (p = 0.0014). During 6-year observation of 97 patients, there were 39 (40%) deaths: 25 (50%) subjects in the ES (+) group and 14 (30%) in the ES (–) group (p = 0.036). Independent predictors of death were: the occurrence of ES (HR = 1.93), older age (HR = 1.06), and lower left ventricular ejection fraction (HR = 0.95) (for all p < 0.001). Conclusions Electrical storm in patients after MI with ICD for secondary prevention is a relatively common phenomenon and has a negative prognostic significance. Myocardial infarction of the inferior wall and the absence of coronary revascularization are predisposing factors for the occurrence of an ES.

The Raman, MIR and UV-vis spectroscopy have been used to characterize Omafilcon A material constructing the one of the Proclear family contact lenses. The Omafilcon A is hydrogel material composed of 2-hydroxyethyl methacrylate (HEMA) and 2-methacryloyloxyethyl phosphorylcholine (PC) polymers crosslinked with ethyleneglycol dimethacrylate (EGDMA). Vibrational and electronic properties of the Omafilcon A material were also investigated by quantum chemical calculations. Experimentally obtained Raman, MIR and optical spectra were compared to the theoretical ones calculated applying RHF and DFT methodology. The quantum chemical calculations were performed for isolated monomers of lenses compounds as well as for their dimers and trimers to elucidate the effect of Omafilcon A polymerization and the role of an individual components.

Background Cardiac resynchronization therapy (CRT) reduces morbidity and mortality in heart failure individuals. Despite many efforts 30–40% patients with CRT still do not respond to therapy. Purpose The purpose was to propose and evaluate a novel dyssynchrony scoring system – Regional Strain Pattern Index (RSPI) in prediction of response to CRT. Methods Forty-nine HF patients (age: 66.5±10 years, LV ejection fraction: 24.9±6.4%, QRS: 173.1±19.1 ms, NYHA class II/III: 34.7%/63.3%, ischemic aetiology: 57.1%) underwent CRT implantation. Transthoracic echocardiography was performed before and 15±7 months after CRT implantation. Baseline dyssynchrony was studied by standard indices, strain pattern analysis and novel, author's index- RSPI. RSPI constitutes a method of quantification of LBBB-related strain curve pattern analysis. RSPI was calculated using longitudinal strain by 2D speckle tracking as the sum of dyssynchronous components across 12 segments from all three apical views. In one view, four components were assessed: 1) the contraction of the early-activated wall, 2) the prestretching of the late activated wall, 3) the contraction of the early-activated wall in the first 70% of the systolic ejection phase and 4) the peak contraction of the late-activated wall after aortic valve closure. One point was attributed to each component, thus the maximum was 12 points. RSPI was prospectively evaluated in predicting response to CRT. The response to CRT was defined as ≥15% reduction in the left ventricular end-systolic volume after 15 month follow-up. Results Thirty-six (73.5%) patients were responders. There were no significant differences in the baseline demographics, clinical, echocardiographic parameters between responders and non-responders. The mean RSPI in the overall population was 5.39±2.9 and higher RSPI values were observed in responders (5.86±2.9) than in non-responders (4.08±2.4, p=0.044). The ROC curve indicated that RSPI significantly predicted CRT response (area under curve, AUC=0.691, p=0.014) with the cut-off value at 7 points. Therefore, study population was divided into two groups according to RSPI score: ≥7 points (19 patients, 38.8% of population) and ROC curve for RSPI Conclusion RSPI constitutes a novel, valuable predictor for CRT response. Acknowledgement/Funding Grant for scientific research in the field of CRT efficacy funded by Medical University of Silesia.

In full sunlight, plants often experience a light intensity exceeding their photosynthetic capacity and causing the activation of a set of photoprotective mechanisms. Numerous reports have explained, on the molecular level, how plants cope with light stress locally in photosynthesizing leaves; however, the response of below-ground organs to above-ground perceived light stress is still largely unknown. Since small RNAs are potent integrators of multiple processes including stress responses, here, we focus on changes in the expression of root miRNAs upon high-intensity-light (HL) stress. To achieve this, we used Arabidopsis thaliana plants growing in hydroponic conditions. The expression of several genes that are known as markers of redox changes was examined over time, with the results showing that typical HL stress signals spread to the below-ground organs. Additionally, micro-transcriptomic analysis of systemically stressed roots revealed a relatively limited reaction, with only 17 up-regulated and five down-regulated miRNAs. The differential expression of candidates was confirmed by RT-qPCR. Interestingly, the detected differences in miRNA abundance disappeared when the roots were separated from the shoots before HL treatment. Thus, our results show that the light stress signal is induced in rosettes and travels through the plant to affect root miRNA levels. Although the mechanism of this regulation is unknown, the engagement of miRNA may create a regulatory platform orchestrating adaptive responses to various simultaneous stresses. Consequently, further research on systemically HL-regulated miRNAs and their respective targets has the potential to identify attractive sequences for engineering stress tolerance in plants.

The subject of the study was to determine the effect of erbium ions (Er3 +) on the structure of tellurite glasses. For this purpose, the positron annihilation lifetime and Raman spectroscopy were used. Changes in positron lifetime parameters and the corresponding intensities have been linked to the geometry and the number of free spaces, the pores of which vary from several angstroms to several dozen nanometers under the influence of erbium (Er3+) doped. Experimental spectra of positron lifetime have two constituent lifetimes of positrons − τ1 and τ2. The interpretation of lifetime components was based on the two-state trappingmodel. The application of Raman spectroscopy allowed to assess that the introduction of erbium ions into the tested phosphate tellurite glasses leads to depolymerization of the tellurium subnet.

We introduce a strong extended formulation of the convex recoloring problem on a tree, which has an application in analyzing phylogenetic trees. The extended formulation has only a polynomial number of constraints, but dominates the conventional formulation and the exponentially many valid inequalities introduced by Campelo et al. (Math Progr 156:303–330, 2016). We show that all valid inequalities introduced by Campelo et al. can be derived from the extended formulation. We also show that the natural restriction of the extended formulation provides a complete inequality description of the polytope of subtrees of a tree. The solution time using the extended formulation is much smaller than that with the conventional formulation. Moreover the extended formulation solves all the problem instances attempted in Campelo et al. (2016) and larger sized instances at the root node of the branch-and-bound tree without branching.

The effect of the polydimethylsiloxane (PDMS) based silicone oil, that is widely used in vitreoretinal surgery, on internal structures of the polymer intraocular lenses was investigated. The effect of PDMS was studied on the polymethyl methacrylate (PMMA) rigid lenses and poly(2-hydroxyethyl methacrylate) (PHEMA) flexible lenses. The research was carried out by means of the positron lifetime spectroscopy (PALS) as well as the infrared spectroscopy (FT-IR) and the Raman spectroscopy (RS). The studies involving the use of PALS and FT-IR methods have revealed that the PHEMA based lenses absorbed, whereas the PMMA lenses did not absorb, silicone oil. The results obtained with the use of the RS method were inconclusive, probably due to the too low intensity of the characteristic PDMS bands. The evidence from this study was discussed in terms of physics and related to the clinical use of both silicone oil and intraocular lenses.

The phenomenon of positron–electron annihilation in lifetime measuring mode is considered as a tool to study nanostructurization in solids possessing mixed positron and positronium (Ps) trapping. Structural inhomogeneities due to guest nanoparticles in such solids are described in terms of substitution trapping in positron- and Ps-related sites within the same host matrix. The developed approach allows estimation of interfacial free-volume voids as being responsible for positron trapping and defect-free bulk positron lifetimes of nanoparticle-modified solids. For the example of arsenic sulfide, As4S4 nanoparticles embedded in polyvinylpyrrolidone (PVP) environment under high-energy ball milling, an alternative algorithm to parameterize these structural imperfections is justified. Interfacial free-volume voids between neighboring nanoparticles filled with loosely packed As4S4 crystallites are considered as the most probable positron trapping sites. The observed variations in mixed positron–Ps trapping modes under nanostructurization are adequately defined with respect to the chemistry of guest nanoparticles. Direct evidence for this algorithm is provided as the basis of experimental three-term decomposed positron lifetime spectra for As4S4–PVP nanocomposites parameterized with respect to different fitting protocols.

Background Hydrogel and silicone-hydrogel polymeric materials are widely used in ophthalmology for the manufacture of contact lenses. An important aspect is the investigation of the structure of these materials. Objectives This study has been conducted in order to compare the degree of disorder and presence of free volumes in the internal structure of the polymeric soft contact lenses Omafilcon A (hydrogel) and Comfilcon A (silicone-hydrogel). Differences in the occurrence of trapping centers for positrons and free volumes between the types of investigated contact lenses have been demonstrated. Material and methods Two types of polymeric contact lenses were used as materials: Omafilcon A (hydrogel) and Comfilcon A (silicone-hydrogel). The study was performed using positron annihilation lifetime spectroscopy (PALS). Results When the results of the measurements has been obtained, a graphical curve has created to describe the relationship of the number of annihilation acts in time. Significant changes were observed between the contact lenses investigated in positron trapping in macropores (based on a two-state model) and the presence of free volumes (based on the Tao-Eldrup model). Conclusions The use of the positron annihilation two-state model made it possible to demonstrate that a higher positron trapping rate in macropores occurs in the silicone-hydrogel contact lens. Additionally, calculations using the Tao-Eldrup model show the existence of free volumes in both types of materials. The size and fraction of free volumes is much larger in the silicone-hydrogel contact lens.

The applicability of positron annihilation lifetime (PAL) spectroscopy to identify volumetric changes in nanostructured polymer/filler substances is first verified at the example of commercially available dimethacrylate-based dental restorative composites Charisma® (Heraeus Kulzer GmbH, Germany) affected to light-curing photopolymerization and one-year dry physical ageing. Principal channel governing PAL spectra in these nanocomposites is recognized as mixed positron-Ps trapping, where positronium Ps (i.e. bound positron-electron state) decay occurs in free-volume holes localized preferentially in polymer matrix, while free positron self-annihilation is character for interfacial voids at the surface of filler-particles assemblies in the filler and/or mixed filler-polymer environment. Methodological algorithm for experimental PAL spectra refinement referred to as the x3-x2-CDA (coupling decomposition algorithm) is validated for these nanocomposites, obeying changes in atomic-deficient structure due to direct conversion between positron-trapping and Ps-decaying sites. Straightforward parameterization of the reconstructed PAL spectra allows meaningful identification of free-volume entities responsible for nanostructurization-driven transformations.

Background The effects of external factors such as X-ray irradiation on the structure and physical properties of contact lenses are very important for both the patients using contact lenses and medical personnel. Objectives The aim of the study was to investigate the effect of X-rays on the structure of Narafilcon A silicone-hydrogel contact lenses. Material and methods In order to study the structural changes caused by X-rays in Narafilcon A polymer contact lenses, the following spectroscopy methods were used: positron annihilation lifetime spectroscopy (PALS), Fourier transform middle infrared spectroscopy (FTIR) and Raman spectroscopy (RS). Irradiation of the investigated sample was carried out using an Elekta Synergy accelerator. The contact lenses were irradiated with the following total doses of X-rays: 0.05 Gy, 0.5 Gy, 0.8 Gy, and 1.0 Gy. Results The PALS measurements showed that X-ray irradiation caused slight changes in the size of the free volume and the fractional free volume in the structure of the polymer contact lenses examined. However, the FTIR and RS measurements showed that X-rays did not break the monomer bonds in the polymeric structure of the sample. Conclusions The changes revealed by the PALS method may be related to possible displacement of monomer chains, resulting in changes in the dimensions and numbers of free volumes. The finding that X-ray radiation does not affect or damage polymer bonds can in the future contribute to the use of X-ray and gamma radiation to sterilize contact lenses.

The expression of two genes encoding xyloglucan endotransglucosylase/hydrolases (XTHs), Cs-XTH1 and Cs-XTH3, was upregulated during the onset of cucumber somatic embryogenesis. As a means of characterising the developmental regulation of these genes, the activity of the respective upstream regulatory regions was investigated in seedlings and somatic embryos of Arabidopsis thaliana and Cucumis sativus. GUS assays revealed that both genes are under developmental control. In addition, elevated promoter activity was found in the tension-bearing regions of the plant and in response to touch and wounding, which is consistent with the existence of numerous stress-related cis elements in the 5′-regulatory regions. In vivo xyloglucan endotransglucosylase (XET) action assays were performed to gain an overview on the role of XTHs during somatic embryogenesis. The highest XET action was observed in the external cell layers of somatic embryos in the cotyledonary region and in the presumptive region of peg formation. Based on the results, we propose a dual mechanism (one developmental and the second adaptive) for the regulation of Cs-XTH1 and Cs-XTH3 activity wherein the developmental pattern can be modified by mechanical stimuli.

Gender aspects continue to play an important role in science education, conditioning study choices or shaping beliefs about one's own capacities and those of others. Performing arts based initiatives are on the forefront of innovative science education approaches and have participatory, dialogic and dialectic qualities to engage students in democratic, inclusive and reflective ways of learning. Both these dimensions can be brought together in order to explore how arts-based science education can contribute to address gender bias and stereotypes in educational and team-collaborative settings. ispartof: Gender and innovation in STE(A)M education status: published

The objective of the study was the structural analysis of the TeO2-P2O5-ZnO-LiNbO3 tellurite glasses doped with ions of the rare-earth elements: Er3+, Nd3+ and Gd3+ based on the PALS (Positron Annihilation Lifetime Spectroscopy) method of measuring positron lifetimes. Values of positron lifetimes and the corresponding intensities may be connected with the sizes and number of structural defects, such as vacancies, mono-vacancies, dislocations or pores, the sizes of which range from a few angstroms to a few dozen nanometres. Experimental positron lifetime spectrum revealed existence of two positron lifetime components τ1 and τ2. Their interpretation was based on two-state positron trapping model where the physical parameters are the annihilation velocity and positron trapping rate.

Atrial fibrillation (AF) significantly increases the risk of thromboembolic events, in particular the risk of stroke. Anticoagulation therapy has been shown to reduce this risk; therefore, the treatment should be lifelong. However, the risk in patients with nonvalvular AF is not equally distributed, and there is a population of patients at low risk. According to the current guidelines, the decision on the need of anticoagulation is primarily dependent on whether the patient is at low risk. The CHA2DS2-VASc is currently the most commonly recommended scheme for assessing thromboembolic risk in patients with nonvalvular AF. In a large group of nontreated patients with a CHA2DS2-VASc of 0 (1 in women), the annual risk of stroke was 0.49%; ischemic stroke, 0.43%; bleeding, 1.08%; intracranial bleeding, 0.15%; and death, 3.87%. In patients on warfarin, the frequency of ischemic stroke was similar. Patients with a CHA2DS2-VASc of 0 (1 in women) are low-risk patients who do not benefit from anticoagulation. The low-risk group is also defined as patients younger than 65 years of age without structural cardiovascular disease, regardless of sex. They represent from 6% to 10% of patients with nonvalvular AF. Thromboembolic risk in patients with a score of 1 (2 in women) is much more controversial, as reflected by several recently published cohort studies. In a Swedish study, the risk was found to be low, while in Danish and Taiwanese studies-as significantly higher. Another analysis has shown that the use of vitamin K antagonists is appropriate when the risk of stroke is higher than 1.7%/year. Owing to a lower risk of intracranial bleeding, anticoagulation with nonvitamin K antagonist oral anticoagulants may be considered already at an annual risk of stroke exceeding 0.9%. Patients at low risk do not require chronic anticoagulation.

This paper is focused on the design, fabrication and characterization of tellurite glass of composition TeO2–WO3–PbO in terms of La2O3 addition. The effect of La2O3 on the structure of the obtained glasses has been investigated by means of spectrophotometric and ellipsometric measurements in the UV-Vis-NIR spectral region and then relevant optical parameters have been calculated. The DC magnetic susceptibility study has been used to investigate the influence of lanthanum ion (La3+) on the structural and magnetic properties of the investigated glass system. Based on DTA, PALS and Raman studies, it can be stated that modification of the basic structural units with La3+ ions, namely the TeO4 trigonal bipyramid (tbp) and the TeO3 trigonal pyramid (tp), both having a lone pair of electrons occupying one of the equatorial positions, affect the magnetic properties of these glasses.