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3552. Pre-portland cements and geopolymers
- Creator:
- Tomáš Hanzlíček, Perná, Ivana, Ertl, Zdenek, and Miller, Sean M.
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Geologie. Meteorologie. Klimatologie, cement, caementum, cementitious, calcareous cement, hydraulic cement, Roman cement, English cement, cement of Boulogne pebbles, Pouilly cement, Russian cement, cement of Baye, aqua-fortis cement, plastic cement, Parker’s cement, common cement, Portland cement, 7, and 551
- Language:
- English
- Description:
- This paper presents the historical background of the 20th-century technology of geopolymers in light of a literature research of the 15th to 19th centuries and offers a hypothesis on why this historical knowledge was forgotten when Portland cement appeared. The recapitulation of the different cementitious calcareous matters returns all the way to the Bible builders; Ancient Vitruvius Pollio’s work "Ten Books of Architecture". These books were not only read but practically proven in pre-Portland times and especially at the beginning of 19th century. The long-term stability of Roman mortars and constructions was studied from the perspective of the cementitious materials, and the cited literature demonstrates the historical evolution of calcareous cements, then the reasons for the interruption of progress and return to the historical experience in the 1980s., Tomáš Hanzlíček, Ivana Perná, Zdenek Ertl and Sean M. Miller., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3553. Precise near real-time GNSS analyses at geodetic observatory Pecný: precise orbit determination and water vapour monitoring
- Creator:
- Jan Douša
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Geologie. Meteorologie. Klimatologie, GPS (navigační systém), geodynamika, GPS (navigation system), geodynamics, near real-time, troposphere delay, GLONASS, precise orbit prediction, 7, and 551
- Language:
- English
- Description:
- This paper provides a summary of the Geodetic Observatory Pecný achievements within the Centre for the Earth Dynamics Research (CEDR, 2005-2009) project in the field of precise near real-time GNSS analyses. The GOP data centre supporting our own near real-time activities as well as those of various other institutes has been enhanced by including GLONASS data, real-time GNSS data and some other supporting products. The ultra-rapid GNSS orbits are routinely determined and predicte dat GOP by analysing a global network of 60 stations. Significant improvements, which resulted in the fitted and predicted satellite positionrms of 4 and 10 cm, respectively, were achieved within the CEDR project. The GOP orbit product is updated every 6 hours and it routinely contributes to the International GNSS Service (IGS). Based on these predicted precise orbits, the GOP near real-time regiona l GNSS network solution is routinely provided for monitoring water vapour in the atmosphere. Resulting zenith troposphere delays achieved a standard deviation of 3-5 cm compared to precise EUREF post-processing results or a standard deviation of 1-2 mm when converted to precipitable water vapour and compared to a nearby radiosonde. The troposphere delays estimated in GOP are operationally used in the Numerical Weather Prediction., Jan Douša., and Obsahuje bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3554. Preclinical atherosclerosis and other determinants of venous thromboembolism in patients with thrombophilias
- Creator:
- Ondřej Auzký, Libuše Pagáčová, Tomáš Šejda, and Jan Piťha
- Format:
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, ultrasonografie, trombóza, ultrasonography, venous thrombosis, preclinical atherosclerosis, venous thromboembolism, thrombophilia, 14, and 612
- Language:
- English
- Description:
- At present, the supposed association between venous thromboembolism and atherosclerosis has yet to be proven. However, no data are available from patients with thrombophilias. We evaluated the association between preclinical atherosclerosis and prevalence of thromboembolic events in patients with thrombophilias. Presence of preclinical atherosclerosis in common carotid and femoral arteries measured by ultrasound was assessed by Belcaro score (based mainly on the presence of plaques) and by measurements of intima media thickness in the same location in 109 patients (43 men, mean age 41.5±13 years) with established thrombophilias. Other parameters under the study were age, presence of traditional cardiovascular risk factors, anthropometric and clinical data including blood pressure measurements and medication. The differences between patients with (n=47) and without (n=62) thromboembolic events were assessed by paired t-test and chi square tests. In patients with a history of venous thromboembolism, body mass index and the prevalence of antihypertensive treatment (AT) were significantly higher than in patients without history of thromboembolism (BMI: 26.5±5.0 vs. 24.4±3.7 kg/m2; p=0.04, AT: 25.5 % vs. 8.1 %; p=0.013). No significant differences between groups were found regarding preclinical atherosclerosis. Overweight and hypertension, but not preclinical atherosclerosis, were more prevalent in patients with thrombophilias suffering from thromboembolism., O. Auzký ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3555. Preconditioning by hypoventilation increases ventricular arrhythmia threshold in wistar rats
- Creator:
- Pavol Švorc and Imola Bračoková
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie, physiology, hypoventilation, cardioprotection, preconditioning, ventricular arrhythmia, rats, 14, and 612
- Language:
- English
- Description:
- Hypoventilation, as one of ventilatory disorders, decreases the electrical stability of the heart similarly as ischemia. If preconditioning by short cycles of ischemia has a cardioprotective effect against harmful influences of a prolonged ischemic period, then preconditioning by hypoventilation (HPC) can also have a similar effect. Anesthetized rats (ketamine 100 mg/kg + xylasine 15 mg/kg i.m., open chest experiments) were subjected to 20 min of hypoventilation followed by 20 min of reoxygenation (control group). The preconditioning (PC) was induced by one (1PC), two (2PC) or three (3PC) cycles of 5-min hypoventilation followed by 5-min reoxygenation. The electrical stability of the heart was measured by a ventricular arrhythmia threshold (VAT) tested by electrical stimulation of the right ventricle. Twenty-minute hypoventilation significantly decreased the VAT in the control and 1PC groups (p<0.05) and non-significantly in 2PC vs. the initial values. Reoxygenation reversed the VAT values to the initial level only in the control group. In 3PC, the VAT was increased from 2.32±0.69 mA to 4.25±1.31 mA. during hypoventilation (p<0.001) and to 4.37±1.99 mA during reoxygenation (p<0.001). It is concluded that cardioprotection against the hypoventilation/ reoxygenation-induced decrease of VAT proved to be effective only after three cycles of HPC., P. Švorc, I. Bračoková., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3556. Preconditioning Modulates Susceptibility to Ischemia-Induced Arrhythmias in the Rat Heart: The Role of a-Adrenergic Stimulation and K(ATP) Channels
- Creator:
- Ravingerová, T., Dezider Pancza, Atila Ziegelhöffer, and Ján Styk
- Format:
- print, bez média, and svazek
- Type:
- article, studie, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie člověka, human physiology, Ischemic preconditioning, Arrhythmias, Adrenergic stimulation, K(ATP) channels, 14, and 612
- Language:
- English
- Description:
- a1_A new concept of cardioprotection based on the exploitation of endogenous mechanisms is known as ischemic preconditioning (IPC). It has been hypothesized that substances released during brief ischemic stress (e.g. catecholamines) stimulate the receptors and trigger multiple cell signaling cascades. Opening of ATP-sensitive K+ channels [K(ATP)] has been suggested as a possible final step in the mechanisms of protection. In this study, the role of adrenergic activation was tested in Langendorff-perfused rat hearts subjected to test ischemia (TI; 30 min occlusion of LAD coronary artery) by: 1) mimicking IPC (5 min ischemia, 10 min reperfusion) with short-term (5 min) administration of norepinephrine (NE, 1 µM), 15 min prior to TI; 2) blockade with b- or a1-receptor antagonists, propranolol (10 µM) and prazosin (2 µM), respectively, applied 15 min prior to TI during IPC. The role of K(ATP) opening was examined by perfusion with a K(ATP) blocker glibenclamide (10 mM) during IPC. Both IPC and NE-induced PC effectively reduced the incidence of ventricular tachycardia (VT) to 33 % and 37 %, respectively, vs 100 % in the non-PC controls, whereby ventricular fibrillation (VF) was totally abolished by IPC and markedly suppressed by PC with NE (0 % and 10 %, respectively, vs 70 % in the non-PC hearts; P<0.05). The severity of arrhythmias (arrhythmia score, AS) was also markedly attenuated by both interventions (IPC: AS 1.7±0.4; NE-PC: AS 1.8±0.3 vs AS 4.1±0.2 in the controls; P<0.05). Protection was not suppressed by propranolol (VT 28 %; VF 14 %; AS 2.2±0.6), whereas prazosin reversed the protective effect of PC (VT 83 %; VF 67 %; AS 4.0±0.8). Antiarrhythmic protection afforded by NE-PC was abolished by pretreatment of rats with pertussis toxin (25 mg/kg, i.p.) given 48 h prior to the experiments., a2_Glibenclamide did not suppress the IPC-induced protection. In conclusion, the sensitivity of the rat heart to ischemic arrhythmias can be modulated by IPC. Protection is mediated via stimulation of a1-adrenergic receptors coupled with Gi-proteins but glibenclamide-sensitive K(ATP) channels do not appear to be involved in the mechanisms of antiarrhythmic protection in this model., T. Ravingerová, D. Pancza, A. Ziegelhoffer, J. Styk., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3557. Predation by Macrolophus pygmaeus (Hemiptera: Miridae) on Acyrthosiphon pisum (Hemiptera: Aphididae): Influence of prey age/size and predator's intraspecific interactions
- Creator:
- Durán Prieto, Juliana, Trotta, Vincenzo, Fanti, Paolo, Castañé, Cristina, and Battaglia, Donatella
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, polokřídlí, klopuškovití, mšicovití, Hemiptera, Miridae, Aphididae, Macrolophus pygmaeus, Acyrthosiphon pisum, pea aphid, polyphagous predator, prey selection, partial prey consumption, 2, and 59
- Language:
- English
- Description:
- Macrolophus pygmaeus (Hemiptera: Miridae) is an important predator of pests of horticultural crops and here its ability as a predator of Acyrthosiphon pisum (Hemiptera: Aphididae) is addressed for the first time. The percentage predation of the different aphid instars and the number partially consumed were studied. Our results, obtained using choice and no-choice tests, revealed that M. pygmaeus caught and consumed more young than later instars of A. pisum, which confirms results of previous studies using other species of aphids. We also studied the interactions between predators (male/female) foraging in the same patch. When the prey/predator ratio is kept constant at 10 : 1 the average percentage of aphids completely consumed by individual females or males does not change with increase in the number of foraging predators. However, the number of partially consumed aphids decreased when females shared the same patch. In contrast, there was an increase in the number of aphids partially consumed when two males shared the same patch. The results were discussed in terms of potential predator foraging strategies since intraspecific competition is a key factor modulating the dynamics of prey-predator systems., Juliana Durán Prieto, Vincenzo Trotta, Paolo Fanti, Cristina Castañé, Donatella Battaglia., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3558. Predicting psychological distress after primary oncological treatment in elderly breast cancer survivors: Retrospective study
- Creator:
- Skřivanová, Kateřina, Svěrák, Tomáš, Brančíková, Dagmar, Jarkovský, Jiří, Benešová, Klára, Anderková, Ľubomíra, Elfmarková, Nela, Peterková, Hana, Bendová, Marie, Minář, Luboš, Holoubková, Eva, Nedvěd, Jan, Protivánková, Markéta, and Dušek, Ladislav
- Format:
- print, text, and regular print
- Type:
- model:article, article, Text, práce podpořená grantem, and TEXT
- Subject:
- dospělí, lidé, lidé středního věku, staří, staří nad 80 let, ženské pohlaví, retrospektivní studie, nádory prsu--psychologie, psychický stres--diagnóza, adaptace psychologická, stupeň závažnosti nemoci, prognóza, lineární modely, multivariační analýza, C-reaktivní protein, úzkost--diagnóza, sebezhodnocení (psychologie), zpráva o sobě, osobnostní dotazník, škála projevu úzkosti--statistika a číselné údaje, and interview psychologický
- Language:
- Czech and English
- Description:
- Cílem této studie bylo stanovit prognózu psychologického distresu u pacientek s karcinomem prsu po primární onkologické léčbě pomocí biologických a psychologických proměnných. Skupina hodnocených pacientek zahrnovala 98 starších pacientek po léčbě karcinomu prsu (ve středním věku 65 let), které vyplnily dotazník SVF 78 (detekce způsobů zvládání stresu), dotazník NEO-FFI (detekce osobnostních rysů), dotazník SCL-90 (zjišťování psychopatologie) po dokončení léčby, a další retrospektivně po diagnóze. Stupnice SAS (měření stupně úzkosti) byla vyplněna menším počtem pacientek. Údaje o faktorech souvisejících s karcinomem a léčbou byly získány z lékařských záznamů. V rámci této studie byl psychologický distres měřen metodou SCL-90 pomocí indexu celkové závažnosti Global Severity Index (GSI) a indexu zátěže pozitivních příznaků Positive Symptom Distress Index (PSDI). Kvantifikace vztahu mezi biologickými a psychologickými prediktory a GSI a PSDI jakožto závislými proměnnými byla vyhodnocena pomocí lineárních regresních modelů s jednou proměnnou i více proměnnými. Po diagnóze a po jednom roce primární léčby byly sledovány hladiny C-reaktivního proteinu. Nejlepší model predikce GSI po léčbě byl zjištěn lineární regresí s více proměnnými jakožto kombinace prediktorů GSI, hladiny CRP a přívětivosti (podškála NEO-FFI) v době diagnózy, v níž R2 = 76,6 %. Nejlepší model predikce PSDI po léčení sestával z hodnoty PSDI, prvku sebeobviňování SVF 78 a stadia nemoci (IV. oproti nižším) v době diagnózy při R2 = 53,9 %. Začlenění celkového hrubého skóre metody SAS do modelů s více proměnnými pro predikci GSI a PSDI způsobilo nárůst hodnoty R2 (ze 71,5 % na 85,0 % a 46,0 % na 65,1 %). Biologické i psychologické prediktory se prokázaly jako významné a vhodné pro predikci psychologického distresu u starších pacientek s karcinomem prsu po dlouhodobém onkologickém léčení. Klíčová slova: C- reaktivní protein – starší přežívající s karcinomem prsu – multivariantní lineární regrese – psychoneuroimunologie – predikce psychologického distresu– retrospektivní studie, The aim of this study was to determine the prognosis of psychological distress in breast cancer survivors after primary oncological treatment using biological and psychological variables. The test group consisted of 98 elderly breast cancer survivors (median age was 65 years) who completed the SVF 78 questionnaire (coping styles measures), NEO-FFI questionnaire (personality traits measures), SCL-90 questionnaire (psychopathology measures) completing treatment and another retrospectively at diagnosis. The SAS scale (anxiety measures) was completed by a lower number of patients. Data on tumour-related factors and treatment were obtained from medical records. Within the scope of this study, psychological distress was measured via the SCL-90 method using Global Severity Index (GSI) and Positive Symptom Distress Index (PSDI). Quantification of the relationship between biological and psychological predictors and GSI and PSDI as dependent variables was estimated using both univariate and multivariate linear regression models. C-reactive protein levels were monitored at diagnosis and one year after primary treatment. The best model for the prediction of GSI after treatment was identified by multivariate linear regression as the combination of GSI, CRP level and agreeableness (NEO-FFI subscale) predictors at the time of diagnosis in which R2 = 76.6 %. The best model for predicting PSDI after treatment consisted of PSDI, the self-accusation component of SVF 78 and the stage of the disease (IV vs lower) at the time of diagnosis with R2 = 53.9 %. Incorporating the total raw score of the SAS questionnaire into the multivariate models for prediction of GSI and PSDI caused an increase in R2 (71.5 % to 85.0 % and 46.0 % to 65.1 %), respectively. Both biological and psychological predictors proved significant and suitable for psychological distress prediction in elderly breast cancer survivors after long-term oncological treatment. Key words: C-reactive protein – elderly breast cancer survivors – multivariate linear regression – psychoneuroimmunology – psychological distress prediction – retrospective study, and Kateřina Skřivanová, Tomáš Svěrák, Dagmar Brančíková, Jiří Jarkovský, Klára Benešová, Ľubomíra Anderková, Nela Elfmarková, Hana Peterková, Marcela Bendová, Luboš Minář, Eva Holoubková, Jan Nedvěd, Markéta Protivánková, Ladislav Dušek
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
3559. Prediction of adrenocortical insufficiency after pituitary adenoma surgery using postoperative basal cortisol levels
- Creator:
- Hána, V., Jana Ježková, Mikuláš Kosák, Michal Kršek, Marek, J., David Netuka, Hill, M., and Václav Hána
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, adenomy hypofýzy, chirurgie, pituitary adenomas, surgery, adrenal insufficiency, hypocorticalism, ACTH test, 14, and 612
- Language:
- English
- Description:
- Our aim was to analyze the correlation of early postoperative cortisol levels in patients after transsphenoidal pituitary adenoma surgery compared to the standard dose ACTH test and Insulin tolerance test (ITT) several months later. We retrospectively reviewed data from 94 patients operated for pituitary adenoma in years 2009-2012. The comparison of day 7 (median) postoperative basal cortisol levels and 3.6 months (median) after pituitary adenoma surgery stimulation test - standard dose 250 μg 1-24ACTH test in 83 patients or ITT in 11 patients were performed. All 16 patients with early postoperative cortisol levels >500 nmol/l proved a sufficient response in the stimulation tests. At basal cortisol levels of 370-500 nmol/l the sufficient response was found in 96 % (27/28) of patients. In the postoperative basal cortisol levels 200-370 nmol/l we found a preserved corticotroph axis later on in 88 % (28/32) of cases. Patients with basal cortisol levels 100-200 nmol/l had a maintained corticotroph axis function in 8/11 cases - 73 %. All patients with an early postoperative basal cortisol level above 500 nmol/l proved in the stimulation tests a preserved corticotroph axis function. The interval 370-500 nmol/l showed a minimal risk of postoperative adrenal insufficiency., V. Hána Jr., J. Ježková, M. Kosák, M. Kršek, J. Marek, D. Netuka, M. Hil, V. Hána., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3560. Predictors of irinotecan toxicity and efficacy in treatment of metastatic colorectal cancer
- Creator:
- Paulík, Adam, Grim, Jiří, and Filip, Stanislav
- Format:
- print, text, and regular print
- Type:
- model:article, article, Text, časopisecké články, práce podpořená grantem, přehledy, and TEXT
- Subject:
- antitumorózní látky fytogenní--škodlivé účinky--farmakokinetika--terapeutické užití, kamptothecin--škodlivé účinky--analogy a deriváty--farmakokinetika--terapeutické užití, kolorektální nádory--genetika--patologie, průjem--chemicky indukované, lidé, neutropenie--chemicky indukované, and farmakogenetika
- Language:
- English
- Description:
- The colorectal cancer ranks high among the malignant tumours in incidence and mortality and irinotecan is standardly used in palliative treatment of metastatic disease in every therapeutic line. Unfortunately, the treatment with irinotecan is often associated with severe toxicities, especially neutropenia and diarrhea. The majority of the toxic manifestation is caused by the insufficient deactivation (glucuronidation) of irinotecan active metabolite SN-38 by UGT1A enzyme. The elevated SN-38 plasma concentration is responsible for the hematological and gastrointestinal toxicity that can become life-threatening. The patients carrying the mutation of the gene encoding UGT1A enzyme lack the ability of bilirubin glucuronidation, and suffer from the inherited un-conjugated hyperbilirubinemia (Gilbert syndrome, Crigler-Najjar type 1 and 2 syndrome). The mutations in other enzyme systems also play role in the etiopathogenesis of the irinotecan toxicity: CYP3A (cytochrome P-450), ABC family of transmembrane transporters (adenosine-triphosphate binding cassette). The goal of the contemporary research is to determine the predictive factors that will enable the individual adjustment of the individual drug dosage while minimising the adverse effects and maintaining the treatment benefit. and A. Paulík, J. Grim, S. Filip
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public