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1.
Science ; 376(6595): 874-879, 2022 05 20.
Article in English | MEDLINE | ID: mdl-35587960

ABSTRACT

Optical fiber-based sensing technology can drastically improve Earth observations by enabling the use of existing submarine communication cables as seafloor sensors. Previous interferometric and polarization-based techniques demonstrated environmental sensing over cable lengths up to 10,500 kilometers. However, measurements were limited to the integrated changes over the entire length of the cable. We demonstrate the detection of earthquakes and ocean signals on individual spans between repeaters of a 5860-kilometer-long transatlantic cable rather than the whole cable. By applying this technique to the existing undersea communication cables, which have a repeater-to-repeater span length of 45 to 90 kilometers, the largely unmonitored ocean floor could be instrumented with thousands of permanent real-time environmental sensors without changes to the underwater infrastructure.

2.
Mater Sci Eng C Mater Biol Appl ; 84: 118-122, 2018 Mar 01.
Article in English | MEDLINE | ID: mdl-29519419

ABSTRACT

Curcumin (Curc) reacts with zinc di­iodine (ZnI2) in 2:1molar ratio in the presence of an excess of a base triethylamine ((CH3CH2)3N) in methanol (CH3OH) solution towards the amorphous solid material of formula [ZnI2(Curc)2] (1). The complex was characterized by melting point (m.p.), Fourier Transform-Infra Red (FT-IR) and Nuclear Magnetic Resonance of hydrogen nucleus (1H NMR) spectroscopy. The formula of 1 was determined by X-ray fluorescence (XRF) analysis. The retention of the structure in solution was confirmed by 1H NMR spectroscopy. The antimicrobial activity of the complex has been studied against the bacteria Pseudomonas aeruginosa (PAO1). The Minimum Inhibitory Concentrations (MIC) of the compounds 1 and Curc against P. aeruginosa (PAO1) are: 71.3µΜ (75.3µg/mL) for [ZnI2(Curc)2] and 339µM (125µg/mL) for Curc, respectively. Moreover, the antimicrobial activity of the new material which was diffused in polystyrene against biofilm formed by PAO1 was also calculated.


Subject(s)
Anti-Infective Agents/chemistry , Curcumin/chemistry , Anti-Infective Agents/pharmacology , Biological Products/chemistry , Biological Products/pharmacology , Coordination Complexes/chemical synthesis , Coordination Complexes/chemistry , Coordination Complexes/pharmacology , Curcumin/pharmacology , Drug Compounding , Magnetic Resonance Spectroscopy , Microbial Sensitivity Tests , Polystyrenes/chemistry , Pseudomonas aeruginosa/drug effects , Spectroscopy, Fourier Transform Infrared , X-Ray Diffraction , Zinc/chemistry
3.
J Sports Med Phys Fitness ; 54(4): 456-74, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24739257

ABSTRACT

Overweight and obesity are widespread nutritional disorders. Their treatment aims at effective weight loss (WL) and weight loss maintenance (WLM). Previous systematic reviews show weight regain, after recommended exercise and diet combined. However, certain experimental and methodological inconsistencies in the original studies and in these reviews left space for a substantial revisit of this problem. This study aimed at systematically re-reviewing the effectiveness of exercise combined with diet on WLM in overweight and obese adults. Literature was searched through Embase and Sport Discus (up to 2008), and PubMed (Medline) and ISI Web of science (up to 2012). 14 randomized clinical trials (RCT) were retained, their quality was assessed by the Jadad scale, and detailed methodological and statistical characteristics were evaluated. Overall estimations showed a WL of 11.1 kg (about 13%) after an average of about 4 months from baseline, a WLM of 5.8 kg (about 52%) and a weight regain of 5.1 kg after an average period of about 21 months. WL was successful but almost half of it (about 48%) was regained, which agrees with previous findings. The Jadad score showed very good to excellent quality for all 14 studies. However, further assessment revealed serious weakness such as high average dropout (>20%), not estimating experimental power or not using a control group in more than half of the studies, possible lack of adherence and variability in demographic traits. Future studies may focus on improving these limitations for more accurate results in this crucial research field.


Subject(s)
Diet, Reducing , Exercise Therapy , Obesity/therapy , Overweight/therapy , Weight Loss , Humans , Research Design
4.
J Sports Med Phys Fitness ; 50(4): 465-74, 2010 Dec.
Article in English | MEDLINE | ID: mdl-21178934

ABSTRACT

AIM: Soccer players possess various degrees of functional footedness. Their lower limbs are subjected to consistent asymmetrical workloads and neuromuscular adaptations, and as a result develop asymmetrical patterns of musculoskeletal function. This study focused on the myodynamic profile of the knee and ankle joint in professional soccer players. Special emphasis was put on the multivariate quantification of three types of asymmetry: directional (left vs. right), fluctuating (dominant vs. non dominant) and absolute (left vs. right). METHODS: One-hundred professional soccer players (mean age 23.4 years, weight 73.3, height 177.6) were tested isokinetically for concentric and eccentric isokinetic muscle strength (1) of the knee flexors and extensors, and (2) of the ankle dorsal and plantar flexors. Knee flexion-extension was tested at 60o, 180o and 300o/s for the concentric mode of contraction and at 60o and 180o/s for the eccentric. The ankle joint was tested only at 60o/s for both the concentric and eccentric action. RESULTS: MANOVA showed significances for all three types of strength asymmetry (joint and action combined): directional (Wilks' Λ=0.66, F=2.957, P=0.001), fluctuating (Wilks' Λ=0.61, F=2.957, P=0.007), and absolute asymmetry (Wilks' Λ=0.47, F=116.26, P=0.000). Several significant asymmetries were also revealed at the univariate level of analysis (P<0.05). CONCLUSION: It seems that the lower limbs of professional soccer players are characterized by significant compound muscle strength asymmetries. These findings substantiate the idea of asymmetry in the myodynamic adaptations that take place at the knee and ankle joint of soccer players during the game. Individual modification of the training load, targeting in strength asymmetry correction, should be taken into consideration for injury prevention.


Subject(s)
Ankle Joint/physiology , Knee Joint/physiology , Muscle Strength/physiology , Soccer/physiology , Adult , Humans , Multivariate Analysis , Muscle Contraction/physiology , Young Adult
5.
Foot (Edinb) ; 19(1): 29-35, 2009 Mar.
Article in English | MEDLINE | ID: mdl-20307446

ABSTRACT

BACKGROUND: Excessive subtalar pronation causes significant changes in the biomechanics of the lower leg, adversely influences proprioceptive feedback and neuromuscular reflex behavior and consequently, affects stability of the foot. However, the changes in muscle strength, caused by hyperpronation are unclear. OBJECTIVES: The purpose of the present study was to compare the evertor and invertor peak torque between hyperpronated and normal individuals as well as between their dominant and non-dominant foot. METHOD: 20 healthy male participants volunteered for this study. Leg dominance was assessed on the basis of a questionnaire and navicular drop measurements were used to classify participants into two groups: hyperpronated (> or =10 mm) and normals (5-9 mm). Isokinetic concentric eversion and inversion muscle group strength was tested at 30 degrees and 120 degrees/s using the Con-Trex MJ isokinetic dynamometer. RESULTS: In all cases, inversion peak torque was greater than eversion peak torque and declined with increasing angular velocity. No significant differences were found for inversion and eversion concentric strength at both speeds tested, neither between normal and hyperpronated individuals neither between their dominant and non-dominant foot. CONCLUSIONS: These results indicate the need re-evaluation of navicular drop values in order to identify normal and abnormal subtalar pronation. The assessment of eccentric contractions is also proposed when examining invertors and evertors isokinetic strength.


Subject(s)
Foot Deformities/physiopathology , Muscle, Skeletal/physiology , Pronation/physiology , Subtalar Joint/physiopathology , Torque , Adult , Humans , Male , Muscle Strength/physiology
6.
Knee Surg Sports Traumatol Arthrosc ; 12(1): 22-9, 2004 Jan.
Article in English | MEDLINE | ID: mdl-14586488

ABSTRACT

Anterior cruciate ligament (ACL) rupture causes instability to the knee joint which leads each patient to a different degree of disability. The purpose of this study was to examine the strength of the quadriceps and the hamstrings in ACL-deficient amateur soccer players at different levels of functional status. Thirty male amateur soccer players were separated into three groups according to their Lysholm score; the high-L1 (Lysholm > or =84), the intermediate-L2 (84> Lysholm > or =72) and the low-L3 (Lysholm <72) knee function groups. The control group consisted of 12 amateur soccer players. The strength of the quadriceps and hamstrings was assessed isokinetically at 60 degrees/s. The quadriceps demonstrated significant deficits of the injured knee compared to the intact knee in all groups, whilst the hamstrings showed significant weakness only in the low function group. Respective percentage deficits in groups L1, L2 and L3 were 13.7%, 16.0% and 18.6% for the quadriceps and 2.4%, 5.6% and 19.2% for the hamstrings. All groups had significant quadriceps weakness which did not differ between the groups. In contrast, the strength deficit of the hamstrings was an indicator of poor knee function, since they were significantly weak only in group L3, which represented patients who clearly failed to compensate for instability symptoms. In groups L1 and L2 the side-to-side differences were within the area of asymmetry measured in the control group. Clinical importance of the results is discussed.


Subject(s)
Anterior Cruciate Ligament Injuries , Joint Instability/physiopathology , Knee Joint/physiopathology , Muscle Weakness/physiopathology , Muscle, Skeletal/physiopathology , Adult , Case-Control Studies , Humans , Male , Soccer/physiology , Torque
7.
Percept Mot Skills ; 74(3 Pt 2): 1151-67, 1992 Jun.
Article in English | MEDLINE | ID: mdl-1501985

ABSTRACT

The purpose of this study was to examine the effects of four teaching methods on several measures of motor skill, self-concept, and social attitudes of 130 fifth-grade children (67 boys, 63 girls), who were randomly chosen from five elementary schools in one area. Teaching methods were systematically applied for 60 teaching days (20 weeks). Measurements were assessed on three occasions (pre-, mid-, and post-experiment). A 4 x 2 x 3 multivariate analysis of covariance showed the 'combined' method most effective in improving the students' motor ability, while 'indirect' and 'game-oriented' methods contributed to the improvement of self-concept and social attitudes, respectively. Since each of the four methods had different effects on various measures made to evaluate whether aims of physical education had been met, the teacher should be aware of many methods and able to implement them in various combinations, depending upon the special features and purposes of a lesson.


Subject(s)
Attitude , Motor Skills , Physical Education and Training/methods , Self Concept , Social Behavior , Child , Female , Greece , Humans , Male , Personality Development , Play and Playthings
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