bluuebunny/crossref_metadata_2025_split huggingface dataset:
Radiation – induced preparation of polyaniline/poly vinyl alcohol nanocomposites and their properties
Authors: Saleh Hoda H. , Sokary Rehab , Ali Zakaria I. 
Published: March 2019

Abstract
Polyaniline (PANI) nanoparticles and PANI/poly vinyl alcohol (PVA) nanocomposite films were synthesized by the oxidative polymerization of aniline and ammonium peroxodisulfate (APS), as an oxidizing agent in aqueous medium. The PANI/PVA nanocomposite films were exposed to γ-irradiation after oxidative polymerization. Synthesized polyaniline (PANI) nanoparticles and PANI/PVA nanocomposite films were characterized by attenuated total reflectance infrared spectroscopy (FTIR-ATR), X-ray diffraction, high resolution scanning electron microscopy, (HRSEM) high resolution transmission electron microscopy, (HRTEM) and UV-VIS absorption spectroscopy. Energy band gap of PANI nanofibers was determined from Tauc’s plots which equal 4.2 eV. Scanning electron microscopy images show that chemically synthesized of polyaniline has nanofibers structure and irradiated PANI/PVA nanocomposite have a mixture of nanorod and nanosphere structures. The transmission electron microscopy show that chemically synthesized of polyaniline has average length in the range 34 ± 10 nm with less wide distribution, where as the irradiated PANI/PVA nanocomposite has coreshell structure.
Spontaneous emergence of language-like and music-like vocalizations from an artificial protolanguage
Authors: Ma Weiyi , Fiveash Anna , Thompson William Forde 
Published: March 2019

AbstractHow did human vocalizations come to acquire meaning in the evolution of our species? Charles Darwin proposed that language and music originated from a common emotional signal system based on the imitation and modification of sounds in nature. Thisprotolanguageis thought to have diverged into two separate systems, with speech prioritizingreferentialfunctionality and music prioritizingemotionalfunctionality. However, there has never been an attempt to empirically evaluate the hypothesis that a single communication system can split into two functionally distinct systems that are characterized by music- and languagelike properties. Here, we demonstrate that when referential and emotional functions are introduced into an artificial communication system, that system will diverge into vocalization forms with speech- and music-like properties, respectively. Participants heard novel vocalizations as part of a learning task. Half referred to physical entities and half functioned to communicate emotional states. Participants then reproduced each sound with the defined communicative intention in mind. Each recorded vocalization was used as the input for another participant in a serial reproduction paradigm, and this procedure was iterated to create 15 chains of five participants each. Referential vocalizations were rated as morespeech-like, whereas emotional vocalizations were rated as moremusic-like, and this association was observed cross-culturally. In addition, a stable separation of the acoustic profiles of referential and emotional vocalizations emerged, with some attributes diverging immediately and others diverging gradually across iterations. The findings align with Darwin’s hypothesis and provide insight into the roles of biological and cultural evolution in the divergence of language and music.
Water in zeolite L and its MOF mimic
Authors: Fois Ettore , Tabacchi Gloria 
Published: March 2019

Abstract
Confinement of molecules in one dimensional arrays of channel-shaped cavities has led to technologically interesting materials. However, the interactions governing the supramolecular aggregates still remain obscure, even for the most common guest molecule: water. Herein, we use computational chemistry methods (#compchem) to study the water organization inside two different channel-type environments: zeolite L – a widely used matrix for inclusion of dye molecules, and ZLMOF – the closest metal-organic-framework mimic of zeolite L. In ZLMOF, the methyl groups of the ligands protrude inside the channels, creating nearly isolated nanocavities. These cavities host well-separated ring-shaped clusters of water molecules, dominated mainly by water-water hydrogen bonds. ZLMOF provides arrays of “isolated supramolecule” environments, which might be exploited for the individual confinement of small species with interesting optical or catalytic properties. In contrast, the one dimensional channels of zeolite L contain a continuous supramolecular structure, governed by the water interactions with potassium cations and by water-water hydrogen bonds. Water imparts a significant energetic stabilization to both materials, which increases with the water content in ZLMOF and follows the opposite trend in zeolite L. The water network in zeolite L contains an intriguing hypercoordinated structure, where a water molecule is surrounded by five strong hydrogen bonds. Such a structure, here described for the first time in zeolites, can be considered as a water pre-dissociation complex and might explain the experimentally detected high proton activity in zeolite L nanochannels.
Decomposition Kinetics of Levofloxacin: Drug-Excipient Interaction
Authors: Nisar Jan , Iqbal Mudassir , Iqbal Munawar , Shah Afzal , Akhter Mohammad Salim , Sirajuddin  , Khan Rafaqat Ali , Uddin Israr , Shah Luqman Ali , Khan Muhammad Sufaid 
Published: March 2019

Abstract
The present study is focused on the thermal decomposition of Levofloxacin in the absence and presence of different excipients (sodium starch glycolate, magnesium stearate, microcrystalline cellulose and lactose using Thermogravimetry (TG). Fourier Transform Infra Red Spectroscopy (FTIR) and Differential Scanning Calorimetry (DSC) were used to study the possible drug – excipient interaction. It has been shown that the interaction of the first three excipients (sodium starch glycolate, magnesium stearate, and microcrystalline cellulose) with Levofloxacin is physical in nature. Lactose was shown to decrease the degradation temperature to a maximum extent. This indicates a strong chemical interaction between the drug and lactose. The activation energies in the former case were found almost similar but deviated considerably in the latter case.
A New Mathematical Approach to Explore the Post-exercise Recovery Process and Its Applicability in a Cold Water Immersion Protocol
Authors: Micheletti Jéssica K. , Vanderlei Franciele M. , Machado Aryane F. , de Almeida Aline C. , Nakamura Fábio Y. , Netto Junior Jayme , Pastre Carlos Marcelo 
Published: March 2019

Abstract
Micheletti, JK, Vanderlei, FM, Machado, AF, de Almeida, AC, Nakamura, FY, Netto Junior, J, and Pastre, CM. A new mathematical approach to explore the post-exercise recovery process and its applicability in a cold water immersion protocol. J Strength Cond Res 33(5): 1266–1275, 2019—The objective of this study was to propose a mathematical model to analyze the post-training recovery of perceptive, functional, metabolic, and autonomic parameters from the use of cold water immersion (CWI) through isolated and combined analysis. Following simulated training, 64 male soccer players were randomized into an experimental group (EG: CWI, 13 ± 1° C; 15 minutes) and a control group (CG: passive recovery; 15 minutes). Perceptive (soreness and perception of recovery), autonomic (heart rate variability [HRV]), metabolic (lactate concentration), and functional parameters (squat jump, T agility test, sprint test, 40-second test, and maximal voluntary isometric contraction) were analyzed before and at specific moments after training (without exceeding 2 hours after training). The variables were analyzed using the raw data, dichotomization of each variable (isolated analysis), and through a mathematical model using the combination of all parameters analyzed (combined analysis). The combined analysis did not demonstrate better efficacy of the EG compared with the CG (69.17 and 63.4%, p = 0.09). In the isolated analysis, a chance of the technique being better was observed in the metabolic parameter at 1 and 2 hours after training (odds ratio, 95% confidence interval = 3.75 [1.01–13.88] and 11.11 [1.25–98.49]), respectively, and in the autonomic parameter at 40–45 minutes after training (4.4 [1.09–17.67]). For the raw data, all parameters analyzed presented recovery by 2 hours after training for both groups. Based on the proposed mathematical model, it is concluded that CWI is not better than the control condition. However, considering the analysis of variables in isolation, the technique presents a better chance of recovery for blood lactate concentration and HRV.
Resisted Sprint Training in Youth: The Effectiveness of Backward vs. Forward Sled Towing on Speed, Jumping, and Leg Compliance Measures in High-School Athletes
Authors: Uthoff Aaron , Oliver Jon , Cronin John , Winwood Paul , Harrison Craig , Lee Jeong Eun 
Published: March 2019

Abstract
Uthoff, A, Oliver, J, Cronin, J, Winwood, P, Harrison, C, and Lee, JE. Resisted sprint training in youth: the effectiveness of backward vs. forward sled towing on speed, jumping, and leg compliance measures in high-school athletes. J Strength Cond Res 35(8): 2205–2212, 2021—Resisted sprinting (RS) is a popular training method used to enhance sprinting performance in youth. However, research has only explored the effects of forward RS (FRS) training. We examined the effects of FRS and backward RS (BRS) and compared these with a traditional physical education curriculum (CON). One hundred fifteen boys (age 13–15 years) were matched for maturity and allocated to either an FRS (n = 34), BRS (n = 46), or CON (n = 35) group. Training groups towed progressively overloaded sleds (20–55% body mass) 2 d·wk−1 for 8 weeks. Pre-training and post-training data were collected for sprinting times over 10 and 20 m, countermovement jump (CMJ) height, and leg stiffness (KN). Performance remained unchanged for the CON group (all p > 0.05), whereas all variables significantly improved (p < 0.05) after BRS, and all but 10-m performance improved after FRS. Compared with the CON, BRS and FRS significantly (p > 0.05) improved CMJ (Effect size [ES] = 0.67 and 0.38) and KN (ES = 0.94 and 0.69), respectively. No differences were found between training groups. The probabilities of improving sprinting performance after BRS (∼70%) were on average ∼10 and ∼8% better than the FRS and CON groups, respectively. The BRS and FRS showed similar probabilities of improving CMJ (75 and 79%) and KN (80 and 81%), respectively, over the CON group. It seems that BRS may be a means to improve sprint performance, and regardless of direction, RS seems to be a beneficial method for improving jumping height and leg stiffness in youth male athletes.
Sports Participation, Physical Activity, and Health-Related Fitness in Youth With Chronic Diseases or Physical Disabilities: The Health in Adapted Youth Sports Study
Authors: Lankhorst Kristel , Takken Tim , Zwinkels Maremka , van Gaalen Leendert , Velde Saskia te , Backx Frank , Verschuren Olaf , Wittink Harriet , de Groot Janke 
Published: March 2019

Abstract
Lankhorst, K, Takken, T, Zwinkels, M, van Gaalen, L, Velde, St, Backx, F, Verschuren, O, Wittink, H, and de Groot, J. Sports participation, physical activity, and health-related fitness in youth with chronic diseases or physical disabilities: the health in adapted youth sports study. J Strength Cond Res 35(8): 2327–2337, 2021—Youth with chronic diseases or physical disabilities (CDPD) often show reduced fitness and physical activity (PA) levels and participate less in organized sports compared with healthy peers. The purpose of this study was to examine the associations between participation in sports and health-related fitness and PA in youth with CDPD. A total of 163 subjects (mean age 14 years; range 8–19 years) with CDPD were included in this cross-sectional study, with 81 participating in organized sports and 82 not. Subjects were recruited between October 2014 and November 2016. Aerobic and anaerobic fitness, agility, and muscle strength were assessed in the laboratory, whereas PA was monitored in daily life using accelerometry during 1 week. Linear regression analyses were used to assess the associations of sports participation (independent variable) with health-related fitness and PA (dependent variables). Results show that youth with CDPD participating in organized sports 2 times a week performed better on all outcome measures. They reached a higher peak oxygen uptake (difference of 4.9 ml O2·kg−1·min−1, P = 0.001) compared with their peers not participating in sports. Also, anaerobic fitness, agility, muscle strength, and PA were all positively associated with sports participation. Moreover, the association between sports participation and aerobic fitness was mediated by PA for 31% (P = 0.045). In conclusion, participation in sports is associated with both higher levels of PA and health-related fitness in youth with CDPD. Promotion and stimulation of participation in sports seems a good way to promote health-related fitness as well as a healthy active lifestyle in youth with CDPD.
Reliability and Validity of a Pool-Based Maximal Oxygen Uptake Test to Examine High-Intensity Short-Duration Freestyle Swimming Performance
Authors: Nagle Elizabeth F. , Nagai Takashi , Beethe Anne Z. , Lovalekar Mita T. , Zera Jacquelyn N. , Connaboy Christopher , Abt John P. , Beals Kimberly , Nindl Bradley C. , Robertson Robert J. , Lephart Scott M. 
Published: March 2019

Abstract
Nagle, EF, Nagai, T, Beethe, AZ, Lovalekar, MT, Zera, JN, Connaboy, C, Abt, JP, Beals, K, Nindl, BC, Robertson, RJ, and Lephart, SM. Reliability and validity of a pool-based maximal oxygen uptake test to examine high-intensity short-duration freestyle swimming performance. J Strength Cond Res 33(5): 1208–1215, 2019—A modality-specific swimming protocol to assess maximal oxygen uptake (Vo
2max
sw
) is essential to accurately prescribe and monitor swimming conditioning programs. Consequently, there is a need for a reliable and valid graded intensity swimming pool test to accurately assess Vo
2max
sw
using indirect calorimetry. The purpose of this study was to assess (a) reliability of an intensity self-regulated swimming pool test of Vo
2max
sw
and (b) validity of a Vo
2max
sw
test using performance swim (PS) time as the criterion. Twenty-nine men (n = 15) and women (n = 14) (age, 23 ± 6.4 years; body mass index, 23.5 ± 3.0 kg·m−2) performed 2 swimming pool Vo
2max
sw
trials (Vo
2max
sw
A and Vo
2max
sw
B), and 2 PS tests (45.7 m [31.20 ± 4.5 seconds] and 182 m [159.2 ± 25.5 seconds]). For test-retest reliability (trials A vs. B), strong correlations (p < 0.05) were found for Vo
2max
sw
(ml·kg−1·min−1) (r = 0.899), O2 pulse (ml O2·beat−1) (r = 0.833), and maximum expired ventilatory volume (L·min−1) (r = 0.785). For performance validity, moderately strong correlations (p < 0.05) were found between Vo
2max
sw
A and 45.7-m (r = −0.543) and 182-m (r = −0.486) swim times. The self-regulated graded intensity swimming pool protocol examined presently is a reliable and valid test of Vo
2max
sw
. Studies should consider the suitability of a Vo
2max
sw
test for military personnel, clinical populations, and injured athletes.
A New Short Track Test to Estimate the VO2max and Maximal Aerobic Speed in Well-Trained Runners
Authors: Pallarés Jesús G. , Cerezuela-Espejo Víctor , Morán-Navarro Ricardo , Martínez-Cava Alejandro , Conesa Elena , Courel-Ibáñez Javier 
Published: March 2019

Abstract
Pallarés, JG, Cerezuela-Espejo, V, Morán-Navarro, R, Martínez-Cava, A, Conesa, E, and Courel-Ibáñez, J. A new short track test to estimate the VO2max and maximal aerobic speed in well-trained runners. J Strength Cond Res 33(5): 1216–1221, 2019—This study was designed to validate a new short track test (Track(1:1)) to estimate running performance parameters maximal oxygen uptake (VO2max) and maximal aerobic speed (MAS), based on a laboratory treadmill protocol and gas exchange data analysis (Lab(1:1)). In addition, we compared the results with the University of Montreal Track Test (UMTT). Twenty-two well-trained male athletes (VO2max 60.3 ± 5.9 ml·kg−1·min−1; MAS ranged from 17.0 to 20.3 km·h−1) performed 4 testing protocols: 2 in laboratory (Lab(1:1)-pre and Lab(1:1)) and 2 in the field (UMTT and Track(1:1)). The Lab(1:1)-pre was designed to determine individuals' Vpeak and set initial speeds for the subsequent Lab(1:1) short ramp graded exercise testing protocol, starting at 13 km·h−1 less than each athlete's Vpeak, with 1 km·h−1 increments per minute until exhaustion. The Track(1:1) was a reproduction of the Lab(1:1) protocol in the field. A novel equation was yielded to estimate the VO2max from the Vpeak achieved in the Track(1:1). Results revealed that the UMTT significantly underestimated the Vpeak (−4.2%; bias = −0.8 km·h−1; p < 0.05), which notably altered the estimations (MAS: −2.6%, bias = −0.5 km·h−1; VO2max: 4.7%, bias = 2.9 ml·kg−1·min−1). In turn, data from Track(1:1) were very similar to the laboratory test and gas exchange methods (Vpeak: −0.6%, bias = <0.1 km·h−1; MAS: 0.3%, bias = <0.1 km·h−1; VO2max: 0.4%, bias = 0.2 ml·kg−1·min−1, p > 0.05). Thus, the current Track(1:1) test emerges as a better alternative than the UMTT to estimate maximal running performance parameters in well-trained and highly trained athletes on the field.
Sex Differences in the Velocity of Muscle Contraction of the Hamstring and Quadriceps Among Recreationally Active Young Adults
Authors: Martín-San Agustín Rodrigo , Medina-Mirapeix Francesc , Alakhdar Yasser , Benítez-Martínez Josep C. 
Published: March 2019

Abstract
Martín-San Agustín, R, Medina-Mirapeix, F, Alakhdar, Y, and Benítez-Martínez, JC. Sex differences in the velocity of muscle contraction of the hamstring and quadriceps among recreationally active young adults. J Strength Cond Res 33(5): 1252–1257, 2019—This study determines sex differences in the velocity of contraction (VC) of 5 isolated muscles (biceps femoris, semitendinosus, rectus femoris, vastus medialis, and vastus lateralis) and in the relationships between them. Thirty-six female and 34 male recreationally active young adults participated in the study. The VC was measured by tensiomyography using normalized response velocity (Vrn) to perform comparisons. Sex comparisons were adjusted by height and mass. The study of relationships was carried out by comparing and calculating means and ratios. Sex differences were observed in the VC of rectus femoris (mean difference = 6.20 mm·s−1; p < 0.001). Conversely, the biceps femoris only showed sex differences in the unadjusted analysis (mean difference = 6.66 mm·s−1; p = 0.002; d = 0.73. Both sexes showed lower VC values of the hamstring with respect to the quadriceps. Female participants showed differences greater than 15% relative to male participants between biceps femoris and quadriceps ratios and in ratios in the hamstring. Thus, our findings in the VC ratios indicate different mechanical contractile properties between sexes in the relations between the hamstring and quadriceps. Our analysis of the VC at these muscles supposes a new possibility to establish the relationships between knee agonists and antagonists, which allow monitoring the changes in the balance of the VC among the muscle groups.
Does stress echocardiography still have a role in the rapid access chest pain clinic post NICE CG95?
Authors: Pettemerides Victoria , Turner Thomas , Steele Conor , Macnab Anita 
Published: March 2019

Abstract

Introduction: The 2016 NICE clinical guideline 95 (CG95) demoted functional imaging to a second-line test following computed tomography coronary angiography (CTCA). Many cardiac CT services in the UK require substantial investment and growth to implement this. Chest pain services like ours are likely to continue to use stress testing for the foreseeable future. We share service evaluation data from our department to show that a negative stress echocardiogram can continue to be used for chest pain assessment.

Methods: 1815 patients were referred to rapid access chest pain clinic (RACPC) between June 2013 and March 2015. 802 patients had stress echocardiography as the initial investigation. 446 patients had normal resting left ventricular (LV) systolic function and a negative stress echocardiogram. At least 24 months after discharge, a survey was carried out to detect major adverse cardiovascular events (MACE) (cardiac death, myocardial infarction, admission to hospital for heart failure or angina, coronary artery disease at angiography, revascularisation by angioplasty or coronary artery bypass grafting) within 2 years.

Results: Overall, 351 patients were successfully followed up. The mean Diamond-Forrester (D-F) score and QRISK2 suggested a high pre-test probability (PTP) of coronary artery disease (CAD). There were nine deaths (eight non-cardiac deaths and one cardiac death). MACE occurred in four patients with a mean time of 17.5 months (11.6–23.7 months). The annual event rate was 0.6%.

Conclusion: A negative stress echocardiogram can reliably reassure patients and clinicians even in high PTP populations with suspected stable angina. It can continue to be used to assess stable chest pain post CG95.
Stance Taking in Social Media: the Analysis of the Comments About Us Presidential Candidates on Facebook and Twitter
Authors: Kriaučiūnienė Roma , La Roux Jefferey , Lauciūtė Miglė 
Published: March 2019

[full article and abstract in English]
The subject of the paper is the analysis of the expression of stance taking in an online environment, mainly in the comments of users of social networks such as Facebook and Twitter about the presidential candidates of the American Presidential Election in 2016. The empirical data analysis was carried out following the ideas of J. W. Du Bois (2007), D. Barton & C. Lee (2013) and R. Englebretson (2007) on stance taking and J. W. Du Bois’ (2007) model of stance triangle, i.e. grouping instances of stance-taking into one of these groups: evaluation, affect or epistemicity, which served as the main framework of this study. The work of linguists D. Barton & C. Lee (2013) on the expression of stance-taking in an online environment were also taken into consideration.
Having in mind the fact that stance identification is a challenging task , i.e. it could be implicitly as well as explicitly expressed and that it should be inferred from different modes of its expression and interpreted with reference to many contextual and intertextual factors, in the current analysis the authors focused on interpretation of linguistic as well as other multimodal means of the expression of stance that were used by users of social networks in their writing spaces on the topic of the Presidential Election in the United States in 2016. It should also be mentioned that the analysis presented in this article offers only one of the many possible interpretations of the data. Moreover, the current paper concentrates mainly on the presentation of the empirical data of the expression of affective stance. However, it should be indicated that in some cases stance types overlap, i.e. one instance could be treated as both taking an affective and an evaluative stance, as judgements and evaluation (i.e. evaluative stance) are often based on feelings (i.e. affective stance).
The main source of the empirical data were the instances of stance taking taken from comments found on Donald Trump’s and Hillary Clinton’s verified Facebook and Twitter pages during their presidential campaigns in 2016. All in all, 147 examples of posts and comments from the social networks Facebook and Twitter were collected: 72 comments incorporating stance taking on Donald Trump‘s posts, and 75 comments including stance taking on Hillary Clinton‘s posts. The results of the empirical data analysis showed that the affective stance was expressed by linguistic as well as multimodal means.