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During the steam explosion pretreatment of plant biomass, degradation products are generated, and some of these have inhibitory activity against biogas production. The aim of this study was to investigate and quantify the effect of selected model inhibitory compounds on methane production. The results showed no significant inhibition of methane production by furfural at concentrations below 1 g/L. In addition, the microbial community was able to restore biogas production inhibited by this compound after a certain time. 5 hydroxymethylfurfural was evaluated as a more potent inhibitor, with a significant effect above 0.2 g/L. Both compounds were more effective inhibitors with cellulose as the carbon substrate, probably reflecting higher sensitivity of the cellulolytic step in biogas production. No significant inhibition was observed for the phenolic compounds tested, gallic and tannic acids, at concentrations of up to 2 g/L. Thus, the compounds investigated should not represent a problem for the biogas production involving steam explosion preprocessed plant biomass.

Recenze publikace - VOZÁR, Jozef a kol.: Sloboda prejavu v rozhodnutiach súdov Bratislava: VEDA, Vydavateľstvo Slovenskej akadémie vied, 2015, 224 s. ISBN 978-80-224-1470-8.

V příspěvku je popsán výzkum populace digitálních imigrantů a digitálních domorodců na katedře cizích jazyků Ekonomické fakulty Technické univerzity v Liberci v České republice. Autorky nejprve definují hlavní pojmy a posléze přehledně shrnují dosažené výsledky výzkumných projektů provedených v zahraničí a v České republice. Představují svůj výzkum, z jehož výsledků získaných pomocí dotazníkového šetření a vyhodnocení projektové práce studentů v hodinách vyplývá, že dovednosti nově přijímaných studentů a jejich motivace pracovat s informačními a komunikačními technologiemi (ICT) v hodinách jsou překvapivě pozitivní. Tato nová situace je příslibem toho, že se v dalším inovování studijního programu má na čem stavět.

Příspěvek zkoumá roli webquests v pregraduálním vzdělávání, nastiňuje jejich strukturování a možné problémy. Řešení problému kultivuje různé inteligence: intrapersonální, interpersonální, lingvistickou, matematickou, prostorovou a existenční. Studenti jsou vedeni k propojování znalostí z jednotlivých studijních disciplín. Studenti se aktivně zapojují do spoluvytváření vědomostí. Tento moderní přístup k výuce povzbuzuje studenty k prvním výzkumným pokusům, k zacházení s informacemi a uspořádávání výsledků. Výuková situace je stimulující a lépe zapamatovatelná. Strukturováním a vedením studenta od snazšího problému k složitějšímu učitelé nabízejí smysluplné vzdělávací dobrodružství, které přinese výsledky, jež student ocení a využije ve své budoucí profesi.

Reprezentační systémy jsou jedním z modelů používaných v neuro-lingvistickém programování (NLP), které se zaměřují na studium toho, jak lidská mysl zpracovává informace. Neuro-lingvisté uvádějí vizuální, auditorní, kinestetické, olfaktorní a chuťové smysly jako součásti tohoto systému, který poskytuje pedagogům jeden z nástrojů ke zkoumání, jak lidé přiřazují význam k událostem a jak jej následně formulují verbálně. Nejčastěji používaný způsob zpracování dat je směs prvních tří základních smyslů uvedených výše. Hlavním cílem tohoto příspěvku je ukázat repertoár úloh a aktivit používaných při práci se třídou, kdy se využívá prvků z teorie NLP a rozmanitých inteligencí. Příspěvek ukáže, jak tato cvičení využívat s vysokoškolskými studenty, kteří se učí obchodní angličtinu a anglický jazyk jako jazyk cizí. Můžeme je využít pro konstruktivistký přístup k budování jejich jazykových strategií a jazykových dovedností a vést je ke změně jejich vzorců vyjadřování.

Tento příspěvek shrnuje dosavadní zkušenosti s použitím Britského národního korpusu v hodinách anglického jazyka u studentů na Ekonomické fakultě TU v Liberci. Protože současné výsledky byly pozitivní, autorka v závěru nastiňuje, jakým způsobem plánuje v zavádění aktivit založených na BNC a rozšiřovat škálu jejich využití v akademickém roce 2009/2010.

Sarcopenia is an independent risk factor for morbidity and mortality in patients suffering from small cell lung cancer (SCLC), however, a universal indicator of sarcopenia usable in clinical practice is still missing. A novel indicator for describing the severity of cancer could be helpful in tailoring the anti-tumor therapy. The aim of this study was to evaluate the computed tomography (CT) scans of total muscle area and radiation attenuation in patients suffering from small cell lung cancer. We used staging CT scans performed at the time of diagnosis to measure total muscle area (TMA) and average psoas density (PD) at level of the 3rd lumbar vertebra. TMA and PD were statistically evaluated in association with overall survival and disease staging. We used Mann-Whitney test and Spearman´s correlation coefficient for statistical testing and p-value under 0.05 was considered statistically significant. Retrospectively we examined 47 patients suffering from SCLC (mean age 65.05±7.3 years, BMI 23.97±4.4 kg/m², BSA 1.77±0.2 m², 30-day mortality was 4.3 % with 10 months median survival). As sarcopenia was pointed TMA under 55 and 39 cm²/m² for men and women respectively. The sarcopenic patients had significantly shorter median survival (7 vs. 11 months, p=0.05). We observed a significant relationship between survival and performance status (Spearman´s correlation, R=-0.39, p=0.05). The patients were divided into two groups according to the extensive (ED, n=34) or limited (LD, n=13) form of the disease. We observed significant difference in PD (42.49±6.1 vs. 47.67±4.5 HU, p=0.006) between ED vs. LD groups. [ABSTRACT FROM AUTHOR]

Introduction: Sarcopaenia seems to be predictive factor for postoperative morbidity and mortality after colorectal resection for cancer. Nevertheless, an ideal sarcopaenic indicator is still to be identified. Aim: To evaluate computed tomography (CT) measured total abdominal muscle area (TAMA), total psoas muscle area (TPA), and psoas density (PD) -- previously described sarcopaenia indicators -- as possible risk factors for postoperative complications in patients after curative colon and rectal resections for colorectal cancer. Material and methods: Consecutive patients after elective curative colon or rectal resection for cancer at a single institution were divided into cohorts with uncomplicated postoperative course or complications Clavien-Dindo grade I-II (Cl-Di 0-II) and complications Clavien-Dindo grade III-V (Cl-Di III-V). Cohorts were statistically tested for significant differences in TAMA, TPA, and PD calculated from preoperative staging CT scans at the level of the third lumbar vertebra. Results: Data of 112 patients were analysed from a prospectively run database; 65 underwent colon and 47 rectal resections. PD was significantly higher in the Cl-Di 0-II cohort compared to the Cl-Di III-V for both colon (42.67 ±6.52 vs. 40.11 ±7.57 HU, p = 0.002) and rectal resections (44.08 ±5.86 vs. 43.03 ±5.70HU, p = 0.016). TAMA and TPA failed to show significant differences. Conclusions: Psoas density is significantly decreased in patients with Clavien-Dindo grade III-V complications after curative resection for colon and rectal cancer. Due to the simplicity and affordability of its assessment from preoperative staging CT scan, it might be considered an optimal sarcopaenic indicator to be utilised in everyday practice. [ABSTRACT FROM AUTHOR]

Introduction: Bariatric procedures lead to changes in body composition. Desired fat loss may be accompanied by decrease of muscle mass, thus raising the risk of sarcopenia. Aim: To detect the risk of sarcopenia in patients 24 months after different bariatric/metabolic (B/M) procedures by DEXA. Material and methods: Consecutive patients scheduled for a B/M procedure underwent DEXA scan and anthropometric assessment before and 24 months after surgery in a prospective manner. Obtained data were tested for significant differences (p < 0.05) to detect body composition changes and occurrence of sarcopenia. The International Physical Activity Questionnaire (IPAQ) was answered at 24 months to assess physical activity. Results: Nineteen patients were enrolled, with no drop-off at follow-up. Body mass index dropped from 42.4 ±6.3 to 30.3 ±4.9 kg/m², with excess weight loss of 72 ±25% and substantial improvement of all relevant anthropometric measurements (p < 0.001). Significant changes in DEXA parameters were observed: fat mass index (19.5 ±4.7 vs. 12.1 ±3.7 kg/m²), estimated visceral adipose area (235.8 ±70.0 vs. 126.5 ±50.4 cm²), lean mass index (22.1 ±2.4 vs. 18.1 ±2.3 kg/m²), appendage lean mass index (9.7 ±1.3 vs. 7.7 ±1.1 kg/m²), bone mineral content (1.22 ±0.1 vs. 1.12 ±0.1 kg), Z score (2.32 vs. 0.96) and T score (0.58 vs. -0.58). A low level of physical activity was recorded at 24 months. Conclusions: B/M procedures lead to significant changes in body composition at 24 months after surgery. DEXA detects these changes effectively. Desired fat loss is associated with significant reduction of skeletal muscle and bone mineral mass. As such, patients after B/M surgery are at risk of sarcopenia. A low level of physical activity may also play a negative role. [ABSTRACT FROM AUTHOR]

Three biodegradable plastics materials, namely pure poly( l -lactide) (PLA), PLA with plasticizer triacetine (TAC) and the mixture PLA/polyhydroxybutyrate (PHB) and TAC were investigated concerning changes of physical properties due to biodegradation in compost at 58 °C up to 16 days. With rising time of degradation in compost, both number and weight molecular masses were decreasing progressively, but only marginal change of the polydispersity index was observed which indicates that biodegradation is not random process. FTIR spectroscopy revealed that in spite of the extensive decrease of molecular weight, no substantial change in chemical composition was found. The most significant modification of the spectra consisted in an appearing of the broad band in region 3100–3300 cm −1 , which was assigned to a formation of biofilm on the sample surfaces. This effect appeared for all three materials, however, it was much more pronounced for samples containing also triacetine. Measurement of changes in crystalline portion confirmed that amorphous phase degrades substantially faster compared to crystalline part. The plasticizer triacetine is disappearing also rather fast from the sample resulting besides other effect also in a temporary increase of Tg, which at the beginning grows almost to the value typical for PLA without plasticizer but later the Tg is decreasing due to substantial changes in molecular weight. Generally during composting, the samples keep shape for up to 8 days, after that time the material disintegrates to rough powder. [ABSTRACT FROM AUTHOR]

Indoor air quality is always influenced by a number of sources of pollution and can be improved by controlling (minimizing the impact) these sources and by efficient ventilation. An important factor influencing the interior is also the outdoor air, which can be contaminated by nearby transport or industrial sources. Studies conducted between 2015 and 2016 focused on describing the environment of a specific group - children attending kindergartens. The intention was to update and expand information on the occurrence of substances in the indoor environment of kindergartens, their trends, existing resources, and problems and cooperative influences. A part of the study was a multifactorial questionnaire submitted to parents of children, consisting of six parts, which included, in addition to general questions, questions about the child's health, its timetable, and information on eating habits, questions about the domestic environment of the child, and questions about the socio-economic state of the family. [ABSTRACT FROM AUTHOR]

Anthracyclines represent one of the important classes of anti-cancer drugs; however, their major disadvantage is their profound cardiovascular toxicity. This study aimed to evaluate influence of anthracyclines on cardiovascular stiffness parameters estimated from pulse wave (PW). PW was measured in 59 cancer survivors treated with anthracyclines in childhood and in 248 healthy age-matched controls. Both patients and controls were divided into three age groups (13 - 15, 16 - 18 and 19 - 24 years). Central PW augmentation index (C-AI75) and augmentation pressure (C-AP75), both normalized to heart rate 75 bpm, were calculated as parameters of arterial wall stiffness. Central Buckberg sub-endocardial viability ratio (SEVR) was calculated as a parameter of diastolic function. Patients and controls were compared in each age group. C-AI75 and C-AP75 were significantly increased in patients in age groups 16 - 18 and 19 - 24 years. SEVR was decreased in patients in the oldest age group. Our results suggest that although toxic influence of anthracyclines to arterial wall and heart are developing during childhood and puberty, they can be detected rather in the adulthood. These changes are yet subclinical; however, their presence indicates potentially increased cardiovascular risk in childhood cancer survivors treated with anthracyclines during childhood. [ABSTRACT FROM AUTHOR]

During the steam explosion pretreatment of plant biomass, degradation products are generated, and some of these have inhibitory activity against biogas production. The aim of this study was to investigate and quantify the effect of selected model inhibitory compounds on methane production. The results showed no significant inhibition of methane production by furfural at concentrations below 1 g/L. In addition, the microbial community was able to restore biogas production inhibited by this compound after a certain time. 5-hydroxymethylfurfural was evaluated as a more potent inhibitor, with a significant effect above 0.2 g/L. Both compounds were more effective inhibitors with cellulose as the carbon substrate, probably reflecting higher sensitivity of the cellulolytic step in biogas production. No significant inhibition was observed for the phenolic compounds tested, gallic and tannic acids, at concentrations of up to 2 g/L. Thus, the compounds investigated should not represent a problem for the biogas production involving steam explosion preprocessed plant biomass. [ABSTRACT FROM AUTHOR]

The degradation mechanism and kinetics of polylactic acid (PLA) nanocomposite films, containing various commercially available native or organo-modified montmorillonites (MMT) prepared by melt blending, were studied under composting conditions in thermophilic phase of process and during abiotic hydrolysis and compared to the pure polymer. Described first order kinetic models were applied on the data from individual experiments by using non-linear regression procedures to calculate parameters characterizing aerobic composting and abiotic hydrolysis, such as carbon mineralization, hydrolysis rate constants and the length of lag phase. The study showed that the addition of nanoclay enhanced the biodegradation of PLA nanocomposites under composting conditions, when compared with pure PLA, particularly by shortening the lag phase at the beginning of the process. Whereas the lag phase of pure PLA was observed within 27 days, the onset of CO 2 evolution for PLA with native MMT was detected after just 20 days, and from 13 to 16 days for PLA with organo-modified MMT. Similarly, the hydrolysis rate constants determined tended to be higher for PLA with organo-modified MMT, particularly for the sample PLA-10A with fastest degradation, in comparison with pure PLA. The acceleration of chain scission in PLA with nanoclays was confirmed by determining the resultant rate constants for the hydrolytical chain scission. The critical molecular weight for the hydrolysis of PLA was observed to be higher than the critical molecular weight for onset of PLA mineralization, suggesting that PLA chains must be further shortened so as to be assimilated by microorganisms. In conclusion, MMT fillers do not represent an obstacle to acceptance of the investigated materials in composting facilities. [ABSTRACT FROM AUTHOR]

The biodegradation of four poly( l -lactic acid) (PLA) samples with molecular weights ( MW ) ranging from approximately 34 to 160 kg mol −1 was investigated under composting conditions. The biodegradation rate decreased, and initial retardation was discernible in parallel with the increasing MW of the polymer. Furthermore, the specific surface area of the polymer sample was identified as the important factor accelerating biodegradation. Microbial community compositions and dynamics during the biodegradation of different PLA were monitored by temperature gradient gel electrophoresis, and were found to be virtually identical for all PLA materials and independent of MW . A specific PLA degrading bacteria was isolated and tentatively designated Thermopolyspora flexuosa FTPLA. The addition of a limited amount of low MW PLA did not accelerate the biodegradation of high MW PLA, suggesting that the process is not limited to the number of specific degraders and/or the induction of specific enzymes. In parallel, abiotic hydrolysis was investigated for the same set of samples and their courses found to be quasi–identical with the biodegradation of all four PLA samples investigated. This suggests that the abiotic hydrolysis represented a rate limiting step in the biodegradation process and the organisms present were not able to accelerate depolymerization significantly by the action of their enzymes. [ABSTRACT FROM AUTHOR]