357 research outputs found
An electromyographic evaluation of dual role breathing and upper body muscles in response to front crawl swimming
The upper body trunk musculature is key in supporting breathing, propulsion, and stabilization during front crawl swimming. The aim of this study was to determine if the latissimus dorsi, pectoralis major, and serratus anterior contributed to the development of inspiratory muscle fatigue observed following front crawl swimming. Fourteen trained swimmers completed a 200-m front crawl swim at 90% of race pace. Maximal inspiratory and expiratory mouth pressures (PImax and PEmax) were assessed before (baseline) and after each swim, and electromyography was recorded from the three muscles. Post-swim PImax fell by 11% (P < 0.001, d = 0.57) and the median frequency (MDF: a measure of fatigue) of the latissimus dorsi, pectoralis major, and serratus anterior fell to 90% (P = 0.001, d = 1.57), 87% (P = 0.001, r = −0.60) and 89% (P = 0.018, d = 1.04) of baseline, respectively. The fall in serratus anterior MDF was correlated with breathing frequency (r = 0.675, P = 0.008) and stroke rate (r = 0.639, P = 0.014). The results suggest that the occurrence of inspiratory muscle fatigue was partly caused by fatigue of these muscles, and that breathing frequency and stroke rate particularly affect the serratus anterior
Local Stellar Kinematics from RAVE data - VII. Metallicity Gradients from Red Clump Stars
We investigate the Milky Way Galaxy's radial and vertical metallicity
gradients using a sample of 47,406 red clump stars from the RAVE DR4. This
sample is more than twice the size of the largest sample in the literature
investigating radial and vertical metallicity gradients. The absolute magnitude
of Groenewegen (2008) is used to determine distances to our sample stars. The
resulting distances agree with the RAVE DR4 distances Binney et al. (2014) of
the same stars. Our photometric method also provides distances to 6185 stars
that are not assigned a distance in RAVE DR4. The metallicity gradients are
calculated with their current orbital positions ( and ) and with
their orbital properties (mean Galactocentric distance, and ),
as a function of the distance to the Galactic plane:
d[Fe/H]/d- dex/kpc for kpc and
d[Fe/H]/d- dex/kpc for kpc. This
reaffirms the radial metallicity gradient in the thin disc but highlights that
gradients are sensitive to the selection effects caused by the difference
between and . The radial gradient is flat in the distance
interval 0.5-1 kpc from the plane and then becomes positive greater than 1 kpc
from the plane. The radial metallicity gradients are also eccentricity
dependent. We showed that d[Fe/H]/d-, -,
- and - dex/kpc for , ,
and sub-samples, respectively, in the distance
interval kpc. Similar trend is found for vertical
metallicity gradients. Both the radial and vertical metallicity gradients are
found to become shallower as the eccentricity of the sample increases. These
findings can be used to constrain different formation scenarios of the thick
and thin discs.Comment: 18 pages, including 16 figures and 6 tables, accepted for publication
in PAS
A COMPARATIVE ANALYSIS OF THE FACTORS THAT INFLUENCE THE BRAND PREFERENCES OF UNIVERSITY STUDENTS STUDYING SPORTS IN TURKEY AND PORTUGAL
The purpose of this study is to find out and compare the factors effective in brand preferences of the students of Ondokuz Mayıs University Yaşar Doğu Faculty of Sport Sciences in Turkey and Instituto Politecnico da Guarda Faculty of Sports in Portugal in terms of sports products. 266 students (170 male, 96 female) attending sports faculties in Turkey and Portugal participated in this study. A questionnaire about the sports products preferences developed by Tozoğlu (2009) was used in order to find out the brand preferences of students. Student t-test was used to determine whether there is a significant difference between sport faculty students in Portugal and in Turkey. Chi square analysis was used to find out whether the students’ reasons for preferring a brand differed in terms of the schools, they were attending. Differences were found between the factors that affected the brand preferences of the students of Ondokuz Mayıs University (OMU) Yaşar Doğu Faculty of Sport Sciences and Instituto Politecnico da Guarda (IPG) Faculty of Sports in sports products. It was found that when compared with the students of IPG, students of OMU preferred brands since they provided quality guarantee, they were indicators of status and they gave a sense of security. It was found that students of OMU and IPG paid attention to the price while buying a brand product. Turkish students were found to be more dependent on brands when compared with Portuguese students. In addition, the price factor in the purchase of branded products is becoming a common element of the students of both countries. The tendency towards branded sporting products can manifest itself in increasing or decreasing proportions relative to advertising and promotional activities. The management of this orientation as a healthy process can be achieved by the effects of planned school education on the cultural structure. Article visualizations
Metallicity and absolute magnitude calibrations for F-G type main-sequence stars in the Gaia era
In this study, photometric metallicity and absolute magnitude calibrations
were derived using F-G spectral type main-sequence stars in the Solar
neighbourhood with precise spectroscopic, photometric and Gaia astrometric data
for UBV photometry. The sample consists of 504 main-sequence stars covering the
temperature, surface gravity and colour index intervals
K, (cgs) and mag, respectively. Stars with
relative trigonometric parallax errors were
preferred from Gaia DR2 data for the estimation of their absolute
magnitudes. In order to obtain calibrations, and colour
indices of stars were preferred and a multi-variable second order equation was
used. Calibrations are valid for main-sequence stars in the metallicity and
absolute magnitude ranges dex and mag,
respectively. The mean value and standard deviation of the differences between
original and estimated values for the metal abundance and absolute magnitude
are dex and mag, respectively. In this work, it has been shown that
more precise iron abundance and absolute magnitude values were obtained with
the new calibrations, compared to previous calibrations in the literature.Comment: 14 pages, 10 figures and 4 tables, accepted for publication in
Astrophysics and Space Scienc
Implementing of aMMP-8 point-of-care test with a modified new disease classification in Finnish adolescent cohorts
Objectives: Periodontitis is a multifactorial biofilm-induced inflammatory disease; however, clinical and radiographic information reflects events that have already occurred. aMMP-8 lateral-flow chairside or point-of-care-test (POC-test) results have also come to complement the overall status of the patient's current situation. The current study aimed to clarify the usefulness of aMMP-8 chairside-test (aMMP-8 POCT) results to alert the initial or early periodontitis in adolescents, a potential periodontitis risk group with cut off 20 ng/ml in Stage I periodontitis, according to the current periodontitis classification system. Material and Methods: A total of 117 adolescents were aMMP-8 POC tested for aMMP-8 levels and examined for the full mouth and were interviewed for questions concerning health behavior. Results: Of all 117 participants, N = 38 (32.5%) was aMMP-8 POCT positive, and N = 34 (29.1%) had at least one 4 mm periodontal deepened pocket; however, only N = 16 (13.7%) had both characteristics. The subclinical stage (N = 47) could not be classified either as gingivitis or Stage I. Of the participants, who did not have any deepened periodontal pockets, 18 tested negative. Conclusions: Stage I is preceded by antecedent stages that should be tackled by oral healthcare prevention and personalized treatment modalities by professionals. Elevated (>20 nglml), positive aMMP-8 POCT results can be regarded as initial alarmer such as emerging risk. This should be utilized in the preventive personalized interventions by oral health professionals.Peer reviewe
Porphyry Cu-Mo-(Au) Mineralization at Paraga Area, Nakhchivan District, Azerbaijan: Evidence from Mineral Paragenesis, Hyrothermal Alteration and Geochemical Studies
The Paraga area is located at the extreme eastern part of Nakhchivan district at the boundary with Armenia. The field study is situated at Ordubad region placed in 9 km from Paraga village and stays at 2300-2800 m height over sea level. It lies within a region of low-grade metamorphic porphyritic volcanic and plutonic rocks. The detailed field studies revealed that this area composed mainly of metagabbro-diorite intrusive rocks with porphyritic character emplaced into meta-andesitic rocks. This complex is later intruded by unmapped olivine gabbroic rocks. The Cu-Mo-(Au) mineralization at Paraga deposit is vein-type mineralization that is essentially related to quartz veins stockwork which cut the dioritic rocks and concentrated at the eastern and northeastern parts of the area with different directions N80W, N25W, N70E and N45E. Also, this mineralization is associated with two shearing zones directed N75W and N15E. The host porphyritic rocks were affected by intense sulfidation, carbonatization, sericitization and silicification with pervasive hematitic alterations accompanied with mineralized quartz veins and quartz-carbonate veins. Sulfide minerals which are chalcopyrite, pyrite, arsenopyrite and sphalerite occurred in two cases either inside these mineralized quartz veins or disseminated in the highly altered rocks as well as molybdenite and also at the peripheries between the altered host rock and veins. Gold found as inclusion disseminated in arsenopyrite and pyrite as well as in their cracks
Porphyry Cu-Mo-(Au) Mineralization at Paraga Area, Nakhchivan District, Azerbaijan: Evidence from Mineral Paragenesis, Hyrothermal Alteration and Geochemical Studies
The Paraga area is located at the extreme eastern part of Nakhchivan district at the boundary with Armenia. The field study is situated at Ordubad region placed in 9 km from Paraga village and stays at 2300-2800 m height over sea level. It lies within a region of low-grade metamorphic porphyritic volcanic and plutonic rocks. The detailed field studies revealed that this area composed mainly of metagabbro-diorite intrusive rocks with porphyritic character emplaced into meta-andesitic rocks. This complex is later intruded by unmapped olivine gabbroic rocks. The Cu-Mo-(Au) mineralization at Paraga deposit is vein-type mineralization that is essentially related to quartz veins stockwork which cut the dioritic rocks and concentrated at the eastern and northeastern parts of the area with different directions N80W, N25W, N70E and N45E. Also, this mineralization is associated with two shearing zones directed N75W and N15E. The host porphyritic rocks were affected by intense sulfidation, carbonatization, sericitization and silicification with pervasive hematitic alterations accompanied with mineralized quartz veins and quartz-carbonate veins. Sulfide minerals which are chalcopyrite, pyrite, arsenopyrite and sphalerite occurred in two cases either inside these mineralized quartz veins or disseminated in the highly altered rocks as well as molybdenite and also at the peripheries between the altered host rock and veins. Gold found as inclusion disseminated in arsenopyrite and pyrite as well as in their cracks
Proton therapy for mandibula plate phantom
Purpose: In this study, the required dose rates for optimal treatment of tumoral tissues when using proton therapy in the treatment of defective tumours seen in mandibles has been calculated. We aimed to protect the surrounding soft and hard tissues from unnecessary radiation as well as to prevent complications of radiation. Bragg curves of therapeutic energized protons for two different mandible (molar and premolar) plate phantoms were computed and compared with similar calculations in the literature. The results were found to be within acceptable deviation values. Methods: In this study, mandibular tooth plate phantoms were modelled for the molar and premolar areas and then a Monte Carlo simulation was used to calculate the Bragg curve, lateral straggle/range and recoil values of protons remaining in the therapeutic energy ranges. The mass and atomic densities of all the jawbone layers were selected and the effect of layer type and thickness on the Bragg curve, lateral straggle/range and the recoil were investigated. As protons move through different layers of density, lateral straggle and increases in the range were observed. A range of energies was used for the treatment of tumours at different depths in the mandible phantom. Results: Simulations revealed that as the cortical bone thickness increased, Bragg peak position decreased between 0.47–3.3%. An increase in the number of layers results in a decrease in the Bragg peak position. Finally, as the proton energy increased, the amplitude of the second peak and its effect on Bragg peak position decreased. Conclusion: These findings should guide the selection of appropriate energy levels in the treatment of tumour structures without damaging surrounding tissues. View Full-Text Keywords: proton treatment, biomaterials, bragg peak, mandible plate phantom, dental tumour, paediatric dentistrypublishedVersio
Pressing issues for oral care quality improvement: findings from the EU DELIVER project
Background: While oral health often takes a backseat to other health domains, it silently affects nearly half of the Worldwide population. The DELIVER project, funded by the EU’s Horizon Europe program, seeks to develop a blueprint model for improving the quality of oral health care for everyone. Methods: Applying the Nominal Group Technique (NGT), 17 stakeholders from various backgrounds participated in identifying pressing issues for oral care quality improvement across practice, community, and policy levels. Results: The results revealed significant differences at the different levels, with accessibility emerging as a prominent issue, encompassing affordability, availability, and acceptability of oral healthcare services. Conclusions: These findings emphasizes the need for policy reforms, increased investments, and a shift towards preventive and patient-centered dental care practices. It highlights the importance of collaborative efforts with multi-stakeholders and prioritizing pressing issues on a multi-level to drive positive change in improving oral care quality. © The Author(s) 2024.The authors disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This project has received funding from the European Union’s Horizon Europe research and innovation program under grant agreement 101057077: https://cordis.europa.eu/project/id/101057077
Role of Porphyromonas gingivalis gingipains in multi-species biofilm formation
BackgroundPeriodontal diseases are polymicrobial diseases that cause the inflammatory destruction of the tooth-supporting (periodontal) tissues. Their initiation is attributed to the formation of subgingival biofilms that stimulate a cascade of chronic inflammatory reactions by the affected tissue. The Gram-negative anaerobes Porphyromonas gingivalis, Tannerella forsythia and Treponema denticola are commonly found as part of the microbiota of subgingival biofilms, and they are associated with the occurrence and severity of the disease. P. gingivalis expresses several virulence factors that may support its survival, regulate its communication with other species in the biofilm, or modulate the inflammatory response of the colonized host tissue. The most prominent of these virulence factors are the gingipains, which are a set of cysteine proteinases (either Arg-specific or Lys-specific). The role of gingipains in the biofilm-forming capacity of P. gingivalis is barely investigated. Hence, this in vitro study employed a biofilm model consisting of 10 ¿subgingival¿ bacterial species, incorporating either a wild-type P. gingivalis strain or its derivative Lys-gingipain and Arg-gingipan isogenic mutants, in order to evaluate quantitative and qualitative changes in biofilm composition.ResultsFollowing 64 h of biofilm growth, the levels of all 10 species were quantified by fluorescence in situ hybridization or immunofluorescence. The wild-type and the two gingipain-deficient P. gingivalis strains exhibited similar growth in their corresponding biofilms. Among the remaining nine species, only the numbers of T. forsythia were significantly reduced, and only when the Lys-gingipain mutant was present in the biofilm. When evaluating the structure of the biofilm by confocal laser scanning microscopy, the most prominent observation was a shift in the spatial arrangement of T. denticola, in the presence of P. gingivalis Arg-gingipain mutant.ConclusionsThe gingipains of P. gingivalis may qualitatively and quantitatively affect composition of polymicrobial biofilms. The present experimental model reveals interdependency between the gingipains of P. gingivalis and T. forsythia or T. denticola
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