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Polycrystalline HfPd2Al has been synthesized using the arc-melting method and studied under ambientpressure conditions by x-ray diffraction from room temperature up to 450 °C. High-pressure x-ray diffraction up to 23 GPa was also performed using Diacell-type membrane diamond anvil cells. The estimated linear thermal expansion coefficient was found to be a = 1.40(3) ×10∼5 K-1, and the bulk modulus derived from the fit to the third-order Birch-Murnaghan equation of state is B0 = 97(2) GPa. Resistivity studies under applied pressure (p ≲ 7.49 GPa) showed a linear decrease of superconducting critical temperature with increasing pressure and the slope dTc/dp = -0.13( 1) K GPa-1. The same behavior is observed for the electron-phonon coupling constant λep(p) that changes from 0.67 to 0.6, estimated for p = 0.05 and 7.49 GPa respectively. First-principles electronic structure and phonon calculation results are presented and used to estimate the magnitude of electron-phonon interaction Aep and its evolution with pressure. Theoretical results e×plain the experimentally observed decrease in Tc due to considerable lattice stiffening. [ABSTRACT FROM AUTHOR]

The unconventional superconductivity in the noncentrosymmetric LaNiC2, and its evolution with pressure, is analyzed basing on the ab initio computations and the full Eliashberg formalism. First-principles calculations of the electronic structure, phonons, and the electron-phonon coupling are reported in the pressure range 0-15 GPa. The thermodynamic properties of the superconducting state were determined numerically solving the Eliashberg equations. We found that already at p = 0 GPa, the superconducting parameters deviate from the BCS-type, and a large value of the Coulomb pseudopotential µ* = 0.22 is required to get the critical temperature Tc = 2.8 K consistent with experiment. If such µ* is used, the Eliashberg formalism reproduces also the experimentally observed values of the superconducting order parameter, the electronic specific heat jump at the critical temperature, and the change of the London penetration depth with temperature. This shows, that deviation of the above-mentioned parameters from the BCS predictions do not prejudge on the triplet or multiple gap nature of the superconductivity in this compound. Under the external pressure, calculations predict continuous increase of the electron-phonon coupling constant in the whole pressure range 0-15 GPa, consistent with the experimentally observed increase in Tc for the pressure range 0-4 GPa, but inconsistent with the drop of Tc above 4 GPa and the disappearance of the superconductivity above 7 GPa, reported experimentally. The disappearance of superconductivity may be accounted for by increasing the µ* to 0.36 at 7 GPa, which supports the hypothesis of the formation of a new high-pressure electronic phase, which competes with the superconductivity. [ABSTRACT FROM AUTHOR]

The introduction of allelopathic cover crops for green manuring or mulching is a regular practice in Integrated Weed Management. In this context, the alternative use of the abundant phytotoxic residues of allelopathic plants from the agroecosystem, e.g., the foliage of Eucalyptus , Acacia , or Cytisus species, is promising. Previous studies identified the phytotoxic compounds potentially involved in the effectiveness of some plant residues when added to the soil for weed control. The low quantities of allelochemicals present in the tissues and the weak phytotoxicity of each of them in their natural concentrations did not explain the significant levels of weed control observed at field scale. Here, to study hypothetical synergistic interactions among the volatile (VOCs) and water-soluble compounds released to the soil matrix, complex mixtures of VOCs, phenolics, or both, mimicking the chemical profiles of Cytisus scoparius were prepared and then tested in vitro on the germination and early growth of two weeds. The effects were calibrated against the VOCs naturally emitted by the fresh plant material and aqueous extract, acting together or not, and with or without soil. The presence of the aqueous extract significantly increased the phytotoxicity of VOCs on Amaranthus retroflexus root growth compared to the volatiles emitted alone. In addition, the soil factor enhanced synergistic interactions among VOCs and water-soluble compounds, resulting in a 54% decrease in total germination and an 80% inhibition of root and shoot growth. Multi-level synergistic chemical interactions should explain the bioherbicidal effectiveness of allelopathic residues applied as a soil amendment.

In our previous studies, the phytotoxicity of Ulex europaeus (gorse) and Cytisus scoparius (Scotch broom) was demonstrated in vitro and argued to be caused by the release of volatile and water-soluble compounds from fresh plant foliage. In light of these positive results, there was a need to test the effects ex vitro . In this work, gorse and Scotch broom were used as soil amendments in pot experiments in a glasshouse by incorporating slashed plant material into the soil at a ratio of 1% w/w on a dry mass basis. The phytotoxic effects on the emergence and early growth of maize and five accompanying weed species were analyzed, as were the effect on soil fertility and soil community-level physiological profiles. Thirty days after incorporation, significant decreases in weed density of 32.2% and 59.5% were found for gorse and Scotch broom soil amendments, respectively. Gorse soil amendment was notably effective impairing the establishment of Amaranthus retroflexus and diminishing the plant height of Digitaria sanguinalis and Portulaca oleracea . Scotch broom soil amendment was capable of significantly inhibiting the emergence of D. sanguinalis , Convolvulus arvensis , P. oleracea , and A. retroflexus , with a notable reduction of weed biomass. No undesirable side effects on maize crop or soil quality, including microbial activity, were detected. Our results suggest that the incorporation of gorse and Scotch broom foliage is promising for pre-emergent weed control in maize; however, field trials that support and expand these glasshouse results are essential.

New herbicides based on natural products are claimed to address weed resistance and environmental concerns related to synthetic herbicides. In our previous studies, certain volatile organic compounds (VOCs) produced by Ulex europaeus and Cytisus scoparius were argued to be responsible for the phytotoxicity of both shrub species. Interactions among VOCs were hypothesized to explain the inconsistency between the effects of the identified pure compounds and those naturally emitted from fresh plant material. In this work, eugenol, verbenone, terpinen-4-ol, α -terpineol, and linalool were assayed as binary mixtures of Amaranthus retroflexus and Digitaria sanguinalis . Powerful synergistic inhibitory effects were revealed for germination and early growth. Only 3.1 ppm of verbenone was enough to inhibit A. retroflexus germination when paired to other VOCs. Eugenol was capable of exacerbating the effects of terpinen-4-ol on A. retroflexus , even though it was innocuous when acting alone at 12.5 ppm. The verbenone and linalool pair produced very significant synergistic effects in terms of D. sanguinalis germination. The synergistic effects were predominantly irreversible for D. sanguinalis , since seeds exposed to paired VOCs were unable to recover their germination capacity after removing the phytotoxins or produced damaged seedlings. Both shrub species have been revealed as sources of natural herbicide molecules, with promising synergistic modes of action that deserve to be studied in depth.

The phytotoxic potential of the legume shrubs Ulex europaeus L. (gorse) and Cytisus scoparius (L.) Link. (Scotch broom) is studied in this work for the first time. On the basis of their richness in active principles, the previous evidence of biological activity, and the abundance of biomass in their native range and invaded areas, a question arose: can U. europaeus and C. scoparius be considered as potential sources of natural herbicides for sustainable agriculture? By means of volatile bioassays, the flowering fresh plant material of both shrub species was shown to produce and emit volatile organic compounds (VOCs) able to inhibit the germination and/or early growth of two agricultural weeds: Amaranthus retroflexus and Digitaria sanguinalis. Novel complete VOCs profiles from the volatile extracts of the shrub species were obtained by GC and GC/MS. A total of 20 compounds were identified from U. europaeus flowering biomass, theaspirane and eugenol, among others, being described in gorse for the first instance. The chemical profile of C. scoparius yielded 28 compounds and was rich in oxygenated monoterpenes such as terpinen-4-ol, verbenol, α-terpineol, and verbenone, which were also identified in this species for the first time. Using dose-response bioassays with pure compounds, these VOCs were argued to be involved in the phytotoxicity observed for the plant materials, even at very low concentrations. The phytotoxic effects were predominantly irreversible, particularly for D. sanguinalis, since the seeds exposed to the VOCs produced damaged seedlings, were unable to recover germination capacity after removing the phytotoxin or, when recovered, produced unviable seedlings. Our results extend the interest of the abundant U. europaeus and C. scoparius for the obtention of natural products with bioherbicide potential, or to be used as allelopathic biomass in the development of new sustainable agricultural practices., Competing Interests: The authors have declared that no competing interests exist.

Introduction: Self-medication can contribute to the inappropriate use of antibiotics in respiratory tract infections (RTI). This phenomenon has not been well described, particularly in Poland. The aim of our study was to describe the prevalence of antibiotic self-medication for RTI, to explore factors influencing antibiotic use without prescription, and to determine the available sources of such antibiotics., Material and Methods: A self-administered questionnaire completed by patients presenting to family medicine clinics at Lodz and Wroclaw from 1(st) March to 15(th) May 2010., Results: A total of 891 patients in ten clinics completed the survey (response rate, 89.1%). Overall, 41.4% (n = 369) of patients reported self-medication with an antibiotic for RTI. The most common reason for antibiotic self-medication was a belief that antibiotics treat the majority of infections, including influenza and influenza-like illnesses (43.9%; n = 162). The predominant sources of antibiotics for self-medication were antibiotics from previous prescriptions stored by the patient at home (73.7%, n = 272), those received from a pharmacy without prescription (13.5%; n = 50), or from family members and friends (12.7%; n = 47)., Conclusions: Antibiotic self-medication for RTI was common in this population. This may be due to the belief that the antibiotics treat the majority of infections. A recommendation to either ask patients to return unused antibiotics to the physician's office or to dispense antibiotics in the exact amount which is necessary for an individual course, as well as the targeted education of pharmacy personnel and the general population, appear to be justified.

OBJECTIVE. To explore whether frequency and duration of sick-leave certification for acute airway infections differ between general practitioners (GPs) in Poland and Norway. DESIGN. Cross-sectional survey. SETTING. Educational courses for GPs. Intervention. We used a questionnaire with four vignettes presenting patients with symptoms consistent with pneumonia, sinusitis, common cold, and exacerbation of chronic obstructive pulmonary disease (COPD), respectively. For each vignette GPs were asked whether they would offer a sick-leave note, and if so, for how many days. Subjects. Convenience samples of GPs in Poland (n = 216) and Norway (n = 171). MAIN OUTCOME MEASURES. Proportion of GPs offering a sick-leave certificate. Duration of sick-leave certification. Results. In Poland 100%, 95%, 87%, and 94% of GPs would offer sick leave for pneumonia, sinusitis, common cold, and exacerbation of COPD, respectively. Corresponding figures in Norway were 97%, 83%, 60%, and 90%. Regression analysis adjusting for the GPs' sex, speciality, experience, and workload indicated that relative risks for offering sick leave (Poland versus Norway) were 1.16 (95% CI 1.07-1.26) for sinusitis and 1.50 (1.28-1.75) for common cold. Among GPs who offered sick leave for pneumonia, sinusitis, common cold, and exacerbation of COPD, mean duration was 8.9, 7.5, 5.1, and 6.9 days (Poland) versus 6.6, 4.3, 3.1, and 6.1 days (Norway), respectively. In regression analyses the differences between the Polish and Norwegian samples in duration of sick leave were statistically significant for all vignettes. A pattern of offering sick leave for three, five, seven, 10, or 14 days was observed in both countries. CONCLUSION. In the Polish sample GPs were more likely to offer sick-leave notes for sinusitis and common cold. GPs in Poland offered sick leaves of longer duration for pneumonia, sinusitis, common colds, and exacerbation of COPD compared with GPs in the Norwegian sample.

Objective: To compare the frequency and duration of sickness certificates issued by GPs to Polish and Norwegian working adults with acute cough/lower respiratory tract infection (LRTI)., Design: Cross-sectional observational study with clinicians from nine primary care centres in Poland and 11 primary care centres in Norway. GPs filled out a case report form for all patients, including information on antibiotic prescribing, sickness certification, and advice to stay off work., Setting: Primary care research networks in Poland and Norway., Subjects: Working adults with a new or worsening cough or clinical presentation suggestive of LRTI., Main Outcome Measures: Issuing sickness certificates and advising patients to stay off work., Results: GPs recorded similar symptoms and signs in patients in the two countries. Antibiotics were prescribed more often in Polish than in Norwegian patients (70.4% vs. 27.1%, p < 0.0001). About half of the patients received a formal sickness certificate (50.5% in Norway and 52.0% in Poland). The proportion of patients advised to stay off work was significantly higher in the Polish sample compared with the Norwegian sample (75.2% vs. 56.1%, p = 0.002). Norwegian GPs less often issued sick certificates for more than seven days (5.6% vs. 36.9%, p < 0.0001)., Conclusion: The overall proportion of sickness certification for acute cough/LRTI was similar in Norwegian and Polish patients. However, in the Polish sample, GPs more often advised patients to take time off work without issuing a sick note. When sickness certificates were issued, duration of longer than seven days was more common in Polish than in Norwegian patients.

Unlabelled: Non-compliance is one of the leading reasons of therapy failure in case of antibiotherapy of respiratory tract infections in children. The organoleptic characteristic of the antibiotic suspension has strong influence on compliance in children. The aim of the present study was to compare taste and the other organoleptic factors of commonly prescribed antibiotics in order to find which of them are palatable to the extent which may positively influence patient compliance., Methods: 13 antibiotic suspensions were arbitrary chosen for the comparison. These drugs were blindly evaluated by 25 volunteers as to the appearance, smell, texture, taste and aftertaste compared to amoxycillin (Amotaks) as a reference dug. The overall score was calculated, as well. In the statistical analysis Duncan's test was used., Results: The important diversity of scores of assessed antibiotics was observed in every category. In most cases clindamycin and macrolides obtained the lowest scores, penicillins and co-trimoxazol--medium ones and cephalosporins--the best scores. Among penicillins, amoxicillins with clavulanic acids were scored lower than pure amoxicillins. In overall score, different preparations of the same substance obtained similar scores, statistically non-different, with one exception for clarithromycin, in which Klacid was characterized by better palatability., Conclusion: Observed differences in organoleptic characteristics of studied drugs may significantly influence patient compliance and therefore should be taken into consideration in the case of antibiotic selection for the treatment of infection in children.

Cardiopulmonary support (CPS) requires durability of the oxygenator. The life span of the oxygenator is affected by various clinical factors, including patient condition, perfusion condition, and equipment usage. Predictors for the durability of oxygenators were evaluated clinically in this study. Thirty-two patients, who had undergone CPS during the last 3 years in our institute were assigned to this study. Fifty oxygenators had been used (Capiox SX in 19, CB Maxima in 23, and AL-6000 in 8). Significant predictors for the durability of oxygenators were evaluated by nonparametric survival analysis and proportional hazards regression analysis. Univariate regression analysis revealed 6 significant predictors for the life span of oxygenators. These were the oxygenator type, type of centrifugal pump, acidosis with blood pH less than 7.35, base excess less than -5, blood glutamic-oxaloacetic transaminase (GOT) levels greater than 1,000 IU, and blood lactate dehydrogenase (LDH) levels greater than 3,000 IU. After multivariate analysis, there remained only 2 significant predictors. An oxygenator used with a noncoated CPS system (Capiox SX with Capiox EBS) proved to have a significantly shorter life span than one used with a heparin-coated system (CB Maxima or AL-6000 with CB BP-80) (hazards ratio, 3.588, p = 0.0065). Patient conditions, which revealed acidosis with less than -5 of base excess, significantly shortened the life of the oxygenator (hazards ratio, 3.595, p = 0.0188).