Physiological Aspects of Different Roller Skiing Techniques in Field Conditions

AbstractThe main goal of the study was to evaluate the impact of different roller skiing techniques (classical CT and skating ST) performed under field conditions on physical capacity variables in cross-country skiers. The second purpose was to evaluate the possibility to use the test results conducted under field and laboratory conditions interchangeably to determine training loads. Eight international-level cross-country skiers (4 male, 4 female) with 8.8 ± 1.3 years of skiing experience took part in the study. The athletes performed three graded tests to exhaustion: two under field conditions (roller skiing CT and ST techniques) and one in the laboratory: treadmill running (TR). All tests were conducted within a period of two weeks to compare general and specific physical capacity outcomes. ANOVA demonstrated significant differences in the threshold heart rate (HRAT4) (ST 175.3 ± 10.8 bpm, CT 175.8 ± 10.9 bpm, TR 181.5 ± 11.1 bpm; p = 0.004), maximal oxygen uptake (VO2max) (ST 64.0 ± 4.65 ml/kg/min, CT 61.5 ± 5.09 ml/kg/min, TR 65.9 ± 2.30 ml/kg/min; p = 0.008) and maximal HR (ST 189.3 ± 10.9 bpm, CT 188.9 ± 10.6 bpm, TR 199.5 ± 10.3 bpm; p = 0.002). No significant differences were observed between classical and skating roller skiing techniques for maximal and threshold values except for threshold velocity (CT 13.4 ± 1.11 km/h vs. ST 14.7 ± 1.17 km/h p = 0.002). Maximal velocity was not measured. The main finding of the study is that it is possible to use threshold HR values obtained in roller skiing tests performed using the classical or skating techniques interchangeably to determine roller skiing training loads. The results of the study indicate that there is a need to verify maximal treadmill running exertion variables in specific roller skiing tests.

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Is using ICT at home good or bad for learning? A cross-country comparison of the impact of home use of ICT for entertainment and learning on PISA 2015 Science test results

10.31219/osf.io/9dv5k ◽

2020 ◽

Cited By ~ 1

Author(s):

Adrian Hatos

Keyword(s):

Regression Models ◽

Large Body ◽

Test Results ◽

Research Results ◽

Ict Use ◽

Country Level ◽

Science Test ◽

Cross Country ◽

The Impact ◽

At Home

There is much contradiction in the results of recent research results concerning the impact of ICT home use by students on learning. Despite the availability of the large body of data from the PISA 2015 survey in which respondents from 47 countries answered the ICT use modules, the research results are still far from conclusive either. Consequently, the purpose of the present research is to explore the cross-country variation of the impact of ICT use at home for entertainment and for learning on the Science test results obtained by students in PISA 2015. More specifically, linear regression models of PISA 2015 Science test results at country-level will be ran, then the variations in betas of the regression models for the 47 countries will be statistically investigated including correlations with other presumably important country-level descriptors. The main conclusions are that is erroneous to expect for positive or negative general effects, as most probably they depend on country-level features, and that the impact of home use, for learning and for entertainment respectively, of ICT are in a kind of homeopathic negative cross-country relationship.

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Impact of external currency exposures on macroeconomic policies

Voprosy Ekonomiki ◽

10.32609/0042-8736-2020-8-23-40 ◽

2020 ◽

pp. 23-40

Author(s):

I. V. Prilepskiy

Keyword(s):

Monetary Policy ◽

Exchange Rate ◽

Positive Impact ◽

Exchange Rate Regime ◽

Macroeconomic Policies ◽

Panel Regressions ◽

Financial Account ◽

Currency Exposure ◽

Cross Country ◽

The Impact

Based on cross-country panel regressions, the paper analyzes the impact of external currency exposures on monetary policy, exchange rate regime and capital controls. It is determined that positive net external position (which, e.g., is the case for Russia) is associated with a higher degree of monetary policy autonomy, i.e. the national key interest rate is less responsive to Fed/ECB policy and exchange rate fluctuations. Therefore, the risks of cross-country synchronization of financial cycles are reduced, while central banks are able to place a larger emphasis on their price stability mandates. Significant positive impact of net external currency exposure on exchange rate flexibility and financial account liberalization is only found in the context of static models. This is probably due to the two-way links between incentives for external assets/liabilities accumulation and these macroeconomic policy tools.

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Model estimates of the results of diabetes patients using modern glucometers with tri-color technology for displaying test results

Medical Technologies Assessment and Choice (Медицинские технологии Оценка и выбор) ◽

10.31556/2219-0678.2019.37.3.081-089 ◽

2019 ◽

pp. 81-89

Author(s):

Larisa Dmitrievna Popovich ◽

Svetlana Valentinovna Svetlichnaya ◽

Aleksandr Alekseevich Moiseev

Keyword(s):

Diabetes Mellitus ◽

Type 2 Diabetes ◽

Type 1 Diabetes ◽

Economic Benefits ◽

Test Results ◽

Self Monitoring ◽

Patients With Diabetes ◽

The Impact

Diabetes – a disease in which the effect of the treatment substantially depends on the patient. Known a study showed that the use of glucometers with the technology of three-color display of test results facilitates self-monitoring of blood sugar and leads to a decrease in glycated hemoglobin (HbAlc). Purpose of the study: to modeling the impact of using of a glucometer with a color-coded display on the clinical outcomes of diabetes mellitus and calculating, the potential economic benefits of reducing the hospitalization rate of patients with diabetes. Material and methods. Based on data from two studies (O. Schnell et al. and M. Baxter et al.) simulation of the reduction in the number of complications with the use of a glucometer with a color indication. In a study by O. Schnell et al. a decrease of HbA1c by 0.69 percent is shown when using the considered type of glucometers, which was the basis of the model. Results. In the model, the use of a glucometer with a color-coded display for type 1 diabetes led to a decrease in the total number of complications by 9.2 thousand over 5 years per a cohort of 40 thousand patients with different initial levels of HbA1c. In a cohort of 40 thousand patients with type 2 diabetes, the simulated number of prevented complications was 1.7 thousand over 5 years. When extrapolating these data to all patients with diabetes included in the federal register of diabetes mellitus (FRD), the number of prevented complications was 55.4 thousand cases for type 1 diabetes and 67.1 thousand cases for type 2 diabetes. The possible economic effect from the use of the device by all patients with a diagnosis of diabetes, which are included in the FRD, estimated at 1.5 billion rubles for a cohort of patients with type 1 diabetes and 5.3 billion rubles for patients with type 2 diabetes. Conclusion. Improving the effectiveness of self-monitoring, which is the result of the use of glucometers with color indicators, can potentially significantly reduce the incidence of complications in diabetes and thereby provide significant economic benefits to society.

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Preanalytical Issues and Cycle Threshold Values in SARS-CoV-2 Real-Time RT-PCR Testing: Should Test Results Include These?

ACS Omega ◽

10.1021/acsomega.1c00166 ◽

2021 ◽

Author(s):

Ilka Engelmann ◽

Enagnon Kazali Alidjinou ◽

Judith Ogiez ◽

Quentin Pagneux ◽

Sana Miloudi ◽

...

Keyword(s):

Real Time ◽

Test Results ◽

Threshold Values ◽

Rt Pcr ◽

Cycle Threshold

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Treadmill Running Changes Endothelial Lipase Expression: Insights from Gene and Protein Analysis in Various Striated Muscle Tissues and Serum

Biomolecules ◽

10.3390/biom11060906 ◽

2021 ◽

Vol 11 (6) ◽

pp. 906

Author(s):

Agnieszka Mikłosz ◽

Bartłomiej Łukaszuk ◽

Adrian Chabowski ◽

Jan Górski

Keyword(s):

Protein Expression ◽

Density Lipoprotein ◽

Treadmill Running ◽

Endothelial Lipase ◽

Type I ◽

Fiber Types ◽

Gene And Protein Expression ◽

Single Bout ◽

The Impact ◽

White Gastrocnemius

Endothelial lipase (EL) is an enzyme capable of HDL phospholipids hydrolysis. Its action leads to a reduction in the serum high-density lipoprotein concentration, and thus, it exerts a pro-atherogenic effect. This study examines the impact of a single bout exercise on the gene and protein expression of the EL in skeletal muscles composed of different fiber types (the soleus—mainly type I, the red gastrocnemius—mostly IIA, and the white gastrocnemius—predominantly IIX fibers), as well as the diaphragm, and the heart. Wistar rats were subjected to a treadmill run: 1) t = 30 [min], V = 18 [m/min]; 2) t = 30 [min], V = 28 [m/min]; 3) t = 120 [min], V = 18 [m/min] (designated: M30, F30, and M120, respectively). We established EL expression in the total muscle homogenates in sedentary animals. Resting values could be ordered with the decreasing EL protein expression as follows: endothelium of left ventricle > diaphragm > red gastrocnemius > right ventricle > soleus > white gastrocnemius. Furthermore, we observed that even a single bout of exercise was capable of inducing changes in the mRNA and protein level of EL, with a clearer pattern observed for the former. After 30 min of running at either exercise intensity, the expression of EL transcript in all the cardiovascular components of muscles tested, except the soleus, was reduced in comparison to the respective sedentary control. The protein content of EL varied with the intensity and/or duration of the run in the studied whole tissue homogenates. The observed differences between EL expression in vascular beds of muscles may indicate the muscle-specific role of the lipase.

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Application of Bacillus pumilus isolates for management of black rot disease in strawberry

Egyptian Journal of Biological Pest Control ◽

10.1186/s41938-021-00371-z ◽

2021 ◽

Vol 31 (1) ◽

Author(s):

Farid Abd-El-Kareem ◽

Ibrahim E. Elshahawy ◽

Mahfouz M. M. Abd-Elgawad

Keyword(s):

Root Rot ◽

Bacillus Pumilus ◽

Field Conditions ◽

Black Rot ◽

Bacterial Isolates ◽

Black Root Rot ◽

Root Rot Disease ◽

Growth Area ◽

Rot Disease ◽

The Impact

Abstract Background Black root rot of strawberry plants caused by Rhizoctonia solani, Fusarium solani, and Pythium sp. is a serious disease in Egypt. Biocontrol agents have frequently proved to possess paramount and safe tools against many diseases. The impact of soil treatments with 3 Bacillus pumilus isolates on black root rot disease of strawberry plants caused by R. solani, F., and Pythium sp. under laboratory and field conditions was examined herein on the commonly used ‘Festival’ strawberry cultivar. To increase the bacterial adhesion and distribution on the roots, each seedling was dipped in bacterial cell suspension at 1 × 108 colony-forming units/ml of each separate bacterial isolate for 30 min then mixed with 5% Arabic gum. Results The tested B. pumilus isolates significantly reduced the growth area of these 3 fungi. The two bacterial isolates Nos. 2 and 3 reduced the growth area by more than 85.2, 83.6, and 89.0% for R. solani, F. solani, and Pythium sp., respectively. Likewise, the 3 bacterial isolates significantly (P ≤ 0.05) inhibited the disease under field conditions. Isolates Nos. 2 and 3 suppressed the disease incidence by 64.4 and 68.9% and disease severity by 65.3 and 67.3%, respectively. The fungicide Actamyl had effect similar to that of the 2 isolates. B. pumilus isolates significantly enhanced growth parameters and yields of strawberry plants; isolates Nos. 2 and 3 raised the yield by 66.7 and 73.3%, respectively. Conclusions Bacillus pumilus isolates could effectively manage the black rot disease in strawberry herein. Due to the significant impact of the root rot disease on strawberry yield, B. pumilus should be further tested to manage the disease on strawberry on large scale in Egypt.

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Do hotel industry operations deteriorate air quality?

Tourism Economics ◽

10.1177/13548166211022423 ◽

2021 ◽

pp. 135481662110224

Author(s):

Liang-Ju Wang ◽

Ming-Hsiang Chen ◽

Zhandong Yang ◽

Ching-Hui (Joan) Su

Keyword(s):

Air Quality ◽

Hotel Industry ◽

Second Step ◽

Test Results ◽

Sales Revenue ◽

Key Indicator ◽

Regression Test ◽

Rolling Regression ◽

The Impact ◽

Regression Tests

This study proposes and tests two hypotheses concerning the effects of hotel industry operations on air quality based on data of 26 major tourist cities in China from 2002 to 2017. The empirical analyses take two steps. In the first step, panel regression test results reveal that hotel industry operations (measured by hotel sales revenue) significantly raise the value of particulate matter (PM)2.5 (the key indicator of air quality), supporting the first hypothesis that hotel industry operations deteriorate air quality and providing empirical evidence of the adverse impact of the hotel industry on air quality. In the second step, subsample analyses support the second hypothesis that the impact of hotel sales revenue on air quality diminishes over time. The results from the rolling regression tests validate the existence of a diminishing effect of hotel industry operations on air quality.

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Viscoelastic Properties of Cell Structures Manufactured Using a Photo-Curable Additive Technology—PJM

Polymers ◽

10.3390/polym13111895 ◽

2021 ◽

Vol 13 (11) ◽

pp. 1895

Author(s):

Tomasz Kozior ◽

Czesław Kundera

Keyword(s):

Viscoelastic Properties ◽

Cellular Structure ◽

Material Selection ◽

Cellular Structures ◽

Test Results ◽

Additive Technology ◽

Polymer Resin ◽

Cell Structures ◽

Relaxation Curves ◽

The Impact

This research paper reviews the test results involving viscoelastic properties of cellular structure models made with the PolyJet Matrix—PJM additive technology. The designed test specimens were of complex cellular structure and made of three various photo-curable polymer resin types. Materials were selected taking into account the so-called “soft” and “tough” material groups. Compressive stress relaxation tests were conducted in accordance with the recommendations of standard ISO 3384, and the impact of the geometric structure shape and material selection on viscoelastic properties, as well as the most favorable geometric variants of the tested cellular structure models were determined. Mathematica and Origin software was used to conduct a statistical analysis of the test results and determine five-parameter functions approximating relaxation curves. The most favorable rheological was adopted and its mean parameters determined, which enables to match both printed model materials and their geometry in the future, to make a component with a specific rheological response. Furthermore, the test results indicated that there was a possibility of modelling cellular structures within the PJM technology, using support material as well.

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Neuronostatin inhibits cardiac contractile function via a protein kinase A- and JNK-dependent mechanism in murine hearts

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.00196.2009 ◽

2009 ◽

Vol 297 (3) ◽

pp. R682-R689 ◽

Cited By ~ 14

Author(s):

Yinan Hua ◽

Heng Ma ◽

Willis K. Samson ◽

Jun Ren

Keyword(s):

Contractile Function ◽

Peptide Hormone ◽

Left Ventricular ◽

Maximal Velocity ◽

Cardiac Contractile Function ◽

Mechanical Responses ◽

Cardiac Contractile ◽

Short Term Exposure ◽

The Impact ◽

Dependent Mechanism

Neuronostatin, a newly identified peptide hormone sharing the same precursor with somatostatin, exerts multiple pharmacological effects in gastrointestinal tract, hypothalamus, and cerebellum. However, the cardiovascular effect of neuronostatin is unknown. The aim of this study was to elucidate the impact of neuronostatin on cardiac contractile function in murine hearts and isolated cardiomyocytes. Short-term exposure of neuronostatin depressed left ventricular developed pressure (LVDP), maximal velocity of pressure development (±dP/d t), and heart rate in Langendorff heart preparation. Consistently, neuronostatin inhibited peak shortening (PS) and maximal velocity of shortening/relengthening (±dL/d t) without affecting time-to-PS (TPS) and time-to-90% relengthening (TR90) in cardiomyocytes. The neuronostatin-elicited cardiomyocyte mechanical responses were mimicked by somatostatin, the other posttranslational product of preprosomatostatin. Furthermore, the neuronostatin-induced cardiomyocyte mechanical effects were ablated by the PKA inhibitor H89 (1 μM) and the Jun N-terminal kinase (JNK) inhibitor SP600125 (20 μM). The PKC inhibitor chelerythrine (1 μM) failed to alter neuronostatin-induced cardiomyocyte mechanical responses. To the contrary, chelerythrine, but not H89, abrogated somatostatin-induced cardiomyocyte contractile responses. Our results also showed enhanced c-fos and c-jun expression in response to neuronostatin exposure (0.5 to 2 h). Taken together, our data suggest that neuronostatin is a peptide hormone with overt cardiac depressant action. The neuronostatin-elicited cardiac contractile response appears to be mediated, at least in part, through a PKA- and/or JNK-dependent mechanism.

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