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1
Çöl, Başak Gökçe, Meryem Akhan, Burcu Çakmak Sancar, Melikenur Türkol, Seydi Yıkmış, and Canan Hecer. "Effect of Thermosonication on Amino Acids, Phenolic Compounds, Sensory Properties and Microbial Quality in Freshly Squeezed Verjuice." Foods 12, no. 11 (May 27, 2023): 2167. http://dx.doi.org/10.3390/foods12112167.
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Thermosonication is a process that can be used as an alternative to thermal pasteurization by combining mild temperature and ultrasound treatments. This study evaluated the effects of verjuice on the thermosonication process and its bioactive values modeled with the RSM (response surface method). The bioactive components of verjuice were found to increase with high predictive values. Additionally, the presence and amounts of 20 free amino acids in C-VJ (untreated verjuice), P-VJ (thermally pasteurized verjuice) and TS-VJ (thermosonicated verjuice) samples were investigated. Significant (p < 0.05) differences were detected among C-VJ, P-VJ and TS-VJ samples in all free amino acid values except methionine. Although 17 free amino acids were detected at various concentrations, glycine, taurine and cystine were not found in any samples. Thirteen phenolic filters in C-VJ, P-VJ and TS-VJ samples were also examined in this study. Eight phenolic donors with various abilities were detected in the C-VJ sample, along with nine phenolic acceptors in the P-VJ sample and eleven phenolic contents in the TS-VJ sample. The content of phenolic products in the TS-VJ sample increased by 37.5% compared to the C-VJ techniques and by 22.22% compared to the P-VJ techniques. Thermosonication did not significantly affect color and physiochemical values. Panelists generally appreciated the effects of thermosonication. It is concluded that the thermosonication process is a good alternative to thermal pasteurization. The results of this study provide essential data for future in vivo studies and show that the bioactive values of verjuice can be increased by using the thermosonication process.
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Pagaduan, Jeffrey, and Haris Pojskic. "A Meta-Analysis on the Effect of Complex Training on Vertical Jump Performance." Journal of Human Kinetics 71, no. 1 (January 31, 2020): 255–65. http://dx.doi.org/10.2478/hukin-2019-0087.
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AbstractComplex training (CT) is a strength training intervention performed by completing all the sets of a resistance exercise followed by a series of high-velocity/plyometric exercise/s. The purpose of this novel study was to conduct a meta-analysis on the effect of CT on vertical jump (VJ) performance. Five electronic databases were searched using terms related to CT and the VJ. Studies needed to include randomized trials comparing CT with traditional resistance training (RT)/plyometric training (PLYO)/control (CON) lasting ≥ 4 weeks and the VJ as a dependent variable. Seven studies qualified for the meta-analysis with two studies differentiating VJ performance from CT and RT, two studies comparing VJ performance of CT and PLYO, and two studies establishing the difference in VJ performance between CT and CON. Results indicated similar improvement in VJ performance from CT and RT (p = 0.88). On the other hand, greater VJ performance in CT than PLYO was identified (ES = 0.86; 95% CI 0.24, 1.47; p = 0.01). CT also showed significantly greater enhancement in VJ compared to CON (ES = 1.14; 95% CI 0.60, 1.68; p < 0.01). In conclusion, CT can serve as alternative training from RT in improving VJ performance. On the other hand, CT is a better option in VJ enhancement than PLYO and CON.
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Peracchia, Camillo. "Gap Junction Channel Regulation: A Tale of Two Gates—Voltage Sensitivity of the Chemical Gate and Chemical Sensitivity of the Fast Voltage Gate." International Journal of Molecular Sciences 25, no. 2 (January 12, 2024): 982. http://dx.doi.org/10.3390/ijms25020982.
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Gap junction channels are regulated by gates sensitive to cytosolic acidification and trans-junctional voltage (Vj). We propose that the chemical gate is a calmodulin (CaM) lobe. The fast-Vj gate is made primarily by the connexin’s NH2-terminus domain (NT). The chemical gate closes the channel slowly and completely, while the fast-Vj gate closes the channel rapidly but incompletely. The chemical gate closes with increased cytosolic calcium concentration [Ca2+]i and with Vj gradients at Vj’s negative side. In contrast, the fast-Vj gate closes at the positive or negative side of Vj depending on the connexin (Cx) type. Cxs with positively charged NT close at Vj’s negative side, while those with negatively charged NT close at Vj’s positive side. Cytosolic acidification alters in opposite ways the sensitivity of the fast-Vj gate: it increases the Vj sensitivity of negative gaters and decreases that of positive gaters. While the fast-Vj gate closes and opens instantaneously, the chemical gate often shows fluctuations, likely to reflect the shifting of the gate (CaM’s N-lobe) in and out of the channel’s pore.
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LU, CHENGBIAO, DAO-QI ZHANG, and DOUGLAS G. McMAHON. "Electrical coupling of retinal horizontal cells mediated by distinct voltage-independent junctions." Visual Neuroscience 16, no. 5 (September 1999): 811–18. http://dx.doi.org/10.1017/s0952523899165015.
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Electrical coupling between H2 horizontal cell pairs isolated from the hybrid bass retina was studied using dual whole-cell, voltage-clamp technique. Voltage-dependent inactivation of junctional currents in response to steps in transjunctional voltage (Vj) over a range of ±100 mV was characterized for 89 cell pairs. Approximately one-quarter of the pairs exhibited strongly voltage-dependent junctions (>50% reduction in junctional current at ±100 mV), another quarter of the pairs exhibited voltage-independent junctional current (<5% reduction at ±100 mV), and the remainder of the pairs exhibited intermediate values for voltage inactivation. We focused on further characterizing the Vj-independent junctions of horizontal cells, which have not been described previously in detail. When Lucifer Yellow dye was included in one recording pipette, pairs exhibiting Vj-independent coupling showed no (9/12), or limited (3/12), passage of dye. Vj-independent coupling was markedly less sensitive to the modulators SNP (100–300 μM, −9% reduction in coupling) and dopamine (100–300 μM, −6%) than were Vj-dependent junctions (−45% and −44%). However, simultaneous application of both SNP and dopamine significantly reduced Vj-independent coupling (−56%). Both Vj-independent and Vj-dependent junctions were blocked by DMSO (1–2%), but Vj-independent junctions were not blocked by heptanol. Single-channel junctional conductances of Vj-independent junctions range from 112–180 pS, versus 50–60 pS for Vj-dependent junctions. The results reveal that Vj-independent coupling in a subpopulation of horizontal cells from the hybrid bass retina is mediated by cellular junctions with physiological and pharmacological characteristics distinct from those previously described in fish horizontal cells.
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Chung, Hyuk-Jin, Hwanhui Lee, Guknam Na, Heechul Jung, Dong-Gun Kim, Sang-Ick Shin, Seong-Eun Jung, et al. "Metabolic and Lipidomic Profiling of Vegetable Juices Fermented with Various Probiotics." Biomolecules 10, no. 5 (May 6, 2020): 725. http://dx.doi.org/10.3390/biom10050725.
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Fermented vegetable juices have gained attention due to their various beneficial effects on human health. In this study, we employed gas chromatography–mass spectrometry, direct infusion-mass spectrometry, and liquid chromatography–mass spectrometry to identify useful metabolites, lipids, and carotenoids in vegetable juice (VJ) fermented with Lactobacillus plantarum HY7712, Lactobacillus plantarum HY7715, Lactobacillus helveticus HY7801, and Bifidobacterium animalis ssp. lactis HY8002. A total of 41 metabolites, 24 lipids, and 4 carotenoids were detected in the fermented and non-fermented VJ (control). The lycopene, α-carotene, and β-carotene levels were higher in VJ fermented with L. plantarum strains (HY7712 and HY7715) than in the control. Proline content was also elevated in VJ fermented with HY7715. Uracil, succinic acid, and α-carotene concentration was increased in VJ fermented with HY7801, while glycine and lycopene levels were raised in VJ fermented with HY8002. This study confirmed that each probiotic strain has distinctive characteristics and produces unique changes to metabolic profiles of VJ during fermentation. Our results suggest that probiotic-fermented VJ is a promising functional beverage that contains more beneficial metabolites and carotenoids than commercial non-fermented VJ.
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Davis, Kyle, Stephen Rossi, Jody Langdon, and Jim McMillan. "The Relationship Between Jumping and Sprinting Performance in Collegiate Ultimate Athletes." Journal of Coaching Education 5, no. 2 (August 2012): 24–37. http://dx.doi.org/10.1123/jce.5.2.24.
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The purpose of the present investigation was to examine the relationship between jumping and sprinting among members of a regionally competitive club-level ultimate team. Twenty-two subjects (mean ± SD; 21.1±2.26 year) volunteered to participate in two testing sessions the week before the team’s regional tournament. Testing sessions included body-composition measurement, a 40-yard sprint (with a 10-yard split time recorded), a standing long jump (LJ) and a vertical jump (VJ). Pearson product-moment correlations revealed a significant negative correlation between LJ and 40-yard sprint time. Significant positive relationships were observed between VJ height and 10-yard power, VJ power and 10-yard power, VJ power and relative 10-yard power, relative VJ power and relative 10-yard power, BJ distance and 10-yard power, VJ height and 40-yard power, VJ power and 40-yard power, and relative VJ power and relative 40-yard power. BJ distance related significantly to 40-yard velocity, 40-yard power and 40-yard relative power. There appears to be a relationship between jumping ability and sprinting in this population, but more studies with this population are needed to confirm these results.
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Zong, Hongliang, Narsimha Reddy Penthala, Siddhartha Sen, Sarah Brennan, Vijayakumar Sonar, Peter A. Crooks, and Monica L. Guzman. "The Acrylonitrile Analog, VJ-289 Ablates Acute Myelogenous Leukemia Blast, Progenitor and Stem Cell Populations by Inducing Tubulin Acetylation and Caspase Activation." Blood 118, no. 21 (November 18, 2011): 2496. http://dx.doi.org/10.1182/blood.v118.21.2496.2496.
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Abstract Abstract 2496 Combretastatin A-4, a derivative of combretastatin, a natural product of the South African tree Combretum caffrum, has been reported to have anti-angiogenic and anti-tubulin effects in different cancer cell lines. We synthesized 48 novel combretastatin analogs to assess anti-leukemia activity in a panel of 12 leukemia cell lines. We identified an analog, VJ-289 [(Z)-3-(1H-indol-2-yl)-2-(3,4,5-trimethoxyphenyl)acrylonitrile] with robust anti-leukemic activity. VJ-289 showed a dose-dependent toxicity to most of the leukemic cell lines tested. The average LD50 for the 12 different leukemia cell lines was 132 nM (95% CI, 91.8–170.5). Specifically, MV4-11 cells demonstrated the most sensitivity to VJ-289 (LD50 = 66 nM), whereas THP-1 was the most resistant (LD50 = 227 nM). Furthermore, when the activity of VJ-289 was tested, five out of 14 primary AML samples demonstrated resistance to VJ-289 with an LD50 > 300nM. The average LD50 for the sensitive primary AML samples was 64.06 nM (95% CI, 35.36–92.76; N=9). Most importantly, normal CD34+ cord blood cells were significantly less affected by VJ-289 (LD50 > 500 nM). Furthermore, VJ-289 was capable of eliminating AML progenitor/stem cells as determined by phenotypic analysis in 15 primary AML samples, colonies forming ability (N=6) and xenotransplant assays (N=6). Overall, we observed a 90.3% decrease in colony formation after treatment with 150 nM VJ-289 relative to untreated control. In contrast, VJ-289 had less impact on colony forming ability of normal hematopoietic stem/progenitor cells from cord blood cells (66.1% decrease relative to untreated; p=0.013). To investigate the role of VJ-289 in leukemic cell apoptosis, various cell survival signaling pathways were examined. Western blotting and intracellular staining/flow cytometry data showed that caspases, including caspase 3 and 8, were activated alongside the cleavage of PARP in a dose-dependent manner. Caspase activation was observed as early as 4 h after treatment with 100 nM VJ-289. PI3K/AKT, MAPK and NF-κB were decreased upon VJ-289 treatment. Moreover, the degradation of MCL1 and the cleavage of Bcl2, two anti-apoptotic Bcl2 family members, were decreased by VJ-289 in a dose- and time-dependent manner. Interestingly, the acetylation of α-tubulin, which is critical for microtubule stabilization, and is involved in multiple cellular functions, ranging from cell motility, cell cycle progression or cell differentiation to intracellular trafficking and signaling, was transiently induced by VJ-289 within 2 hours, and was inhibited dramatically after 4 hours. In summary, we have identified a combrestastatin A-4 analog, VJ-289, as a new anti-leukemia agent with the ability to ablate blast, progenitor and stem cell populations via induction of caspase activation and α-tubulin acetylation. Studies are underway to determine what modulates sensitivity to VJ-289 across AML specimens. Disclosures: No relevant conflicts of interest to declare.
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Xi, Weige, Lixiang Cai, Wutao Shang, and Yidan Su. "On the General Sum Distance Spectra of Digraphs." Mathematics 11, no. 2 (January 6, 2023): 308. http://dx.doi.org/10.3390/math11020308.
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Let G be a strongly connected digraph, and dG(vi,vj) denote the distance from the vertex vi to vertex vj and be defined as the length of the shortest directed path from vi to vj in G. The sum distance between vertices vi and vj in G is defined as sdG(vi,vj)=dG(vi,vj)+dG(vj,vi). The sum distance matrix of G is the n×n matrix SD(G)=(sdG(vi,vj))vi,vj∈V(G). For vertex vi∈V(G), the sum transmission of vi in G, denoted by STG(vi) or STi, is the row sum of the sum distance matrix SD(G) corresponding to vertex vi. Let ST(G)=diag(ST1,ST2,…,STn) be the diagonal matrix with the vertex sum transmissions of G in the diagonal and zeroes elsewhere. For any real number 0≤α≤1, the general sum distance matrix of G is defined asSDα(G)=αST(G)+(1−α)SD(G). The eigenvalues of SDα(G) are called the general sum distance eigenvalues of G, the spectral radius of SDα(G), i.e., the largest eigenvalue of SDα(G), is called the general sum distance spectral radius of G, denoted by μα(G). In this paper, we first give some spectral properties of SDα(G). We also characterize the digraph minimizes the general sum distance spectral radius among all strongly connected r-partite digraphs. Moreover, for digraphs that are not sum transmission regular, we give a lower bound on the difference between the maximum vertex sum transmission and the general sum distance spectral radius.
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Latorre-Román, Pedro Ángel, Felipe García-Pinillos, Emilio José Martínez-López, and Victor Manuel Soto-Hermoso. "Concurrent fatigue and postactivation potentiation during extended interval training in long-distance runners." Motriz: Revista de Educação Física 20, no. 4 (December 2014): 423–30. http://dx.doi.org/10.1590/s1980-65742014000400009.
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The purpose of this study is to analyze acute effect of running extended interval training(EIT) on vertical jump (VJ) and handgrip strength (HS) performance in experienced endurance athletes. In order to analyze mechanical parameters of the VJ and HS between runs, sixteen experienced male athletes performed an EIT (4x3x400m). The results show that fatigue induced by EIT does not impair handgrip strength or VJ performance. A significant improvement (p< .05) was noted for VJ due to the postactivation potentiation (PAP) phenomenon. A positive correlation (r= .619, p= .011) was found between VJ and lactate. The results suggest that experienced long-distance runners can maintain their strength levels and, consequently, work capacity, despite the induced fatigue by the field training demand. Therefore, VJ performance during EIT can be used as an indicator of muscular adaptations to training and, together, with handgrip strength, become indicators of fatigue. These indicators allow proper prescription training routines.
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Pereira, Lucas A., Tomás T. Freitas, Vinicius Zanetti, and Irineu Loturco. "Variations in Internal and External Training Load Measures and Neuromuscular Performance of Professional Soccer Players During a Preseason Training Period." Journal of Human Kinetics 81, no. 1 (January 28, 2022): 149–62. http://dx.doi.org/10.2478/hukin-2022-0012.
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Abstract We described the internal and external training loads (TLs) experienced by soccer players over a 4-week preseason, examined their effects on vertical jump (VJ) performance, and investigated the relationships between different TL variables. Eighteen professional soccer players performed 17 training sessions and 1 friendly-match (FM) over the preseason. The internal TL was obtained using the session-rating of perceived exertion method. The external TL variables collected were total and high-intensity distances, body-load, and high-metabolic power distance via the GPS system. VJ performance was assessed 13 times throughout the study. Moreover, total quality recovery and delayed onset muscle soreness were assessed before every training session as a measure of recovery status. Players were divided, using a median split analysis, into two groups, according to their VJ performance (i.e., “lower” and “higher” VJ). External TL variables displayed similar variations across training sessions and were significantly interrelated (r ranging from 0.48 to 0.88). In periods where higher internal TLs were detected, impaired recovery status was noticed. Notably, the higher VJ group exhibited decreased jump performance at post-test and higher internal and external TLs across the entire preseason (compared to the lower VJ group). From our results it is suggested that professional soccer players with higher VJ performance are potentially more susceptible to concurrent training effects.
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Wang, X. G., and C. Peracchia. "Connexin 32/38 chimeras suggest a role for the second half of inner loop in gap junction gating by low pH." American Journal of Physiology-Cell Physiology 271, no. 5 (November 1, 1996): C1743—C1749. http://dx.doi.org/10.1152/ajpcell.1996.271.5.c1743.
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Gap junction channels are regulated by gates that close with cytosolic acidification and transjunctional voltage (Vj). For identifying the connexin (Cx) domain(s) involved in channel gating, CO2 and Vj sensitivities of channels made of Cx38, Cx32, Cx32/Cx38 chimeras, and Cx32 mutants were studied in Xenopus oocyte pairs. Recently, we have reported that Cx38 is more sensitive to CO2 and Vj than Cx32 because of differences in the Cx inner loop. To identify the responsible inner loop domain, chimeras of Cx32/Cx38 in which the first (I1) or the second (I2) half of the inner loop of Cx38 replaced that of Cx32 and I2 mutants of Cx32 were tested. The chimera Cx32/Cx38I2 (Cx32 with I2 of Cx38) was like Cx38 in CO2 sensitivity but like Cx32 in Vj sensitivity. Cx32/Cx38I1 (Cx32 with I1 of Cx38) did not express channels. Of the three Cx32 mutants, Cx32-VH/IR VH of Cx32 replaced with IR of Cx38) and Cx32-WW/MC WW of Cx32 replaced with MC of Cx38) were like Cx32 in both CO2 and Vj sensitivity, whereas Cx32-S*T/Q*P (S*T of Cx32 replaced with Q*P of Cx38) was closer to Cx38 in CO2 sensitivity but behaved like Cx32 in Vj gating. The data suggest that I1 and I2 contain domains relevant for Vj and CO2 gating, respectively.
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Ernst, Gregory P., Ethan Saliba, David R. Diduch, Shepard R. Hurwitz, and Donald W. Ball. "Lower-Extremity Compensations Following Anterior Cruciate Ligament Reconstruction." Physical Therapy 80, no. 3 (March 1, 2000): 251–60. http://dx.doi.org/10.1093/ptj/80.3.251.
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AbstractBackground and Purpose. Several studies have demonstrated that patients with knee injury scored within a normal range during one-legged hop tests yet showed quadriceps femoris muscle weakness with non–weight-bearing isokinetic testing. This study evaluated lower-extremity kinetics while subjects performed a single-leg vertical jump (VJ) and a lateral step-up (LSU) in an attempt to explain this phenomenon. Subjects and Methods. Using a motion analysis and force platform system, hip, knee, and ankle extension moments of 20 subjects with anterior cruciate ligament (ACL) reconstructions and 20 matched subjects were measured while they performed an LSU and a VJ. Results. An analysis of variance revealed that the knee extension moment of the ACL-reconstructed extremity was lower than that of the uninjured and matched extremities during the LSU, VJ take-off, and VJ landing. However, there was no difference in summated extension moment (hip + knee + ankle) among extremities during the LSU and VJ take-off. The summated extension moment of the ACL-reconstructed extremity during VJ landing was less than that of the uninvolved and matched extremities. Conclusions and Discussion. These results suggest that the hip or ankle extensors may compensate for the knee extension moment deficit. The decrease in summated extension moment in the ACL-reconstructed extremity during VJ landing represents inadequate attenuation of landing forces, which may expose the skeleton and joint structures to injury.
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Keefe, Marcos S., Ryan M. Thiele, and Cameron S. Mackey. "Evaluation of Peak Power Output in Healthy Adults during Sit-to-Stand and Vertical Jump Assessments." Translational Journal of the American College of Sports Medicine 9, no. 2 (2024): 1–5. http://dx.doi.org/10.1249/tjx.0000000000000247.
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ABSTRACT Introduction Measuring maximal, or peak, power output (Pmax) through vertical jumps (VJ) may not be appropriate for all individuals; the sit-to-stand (STS) test could potentially be more functionally relevant for older adults. However, the reliability of measuring Pmax in conjunction with STS and the relationships between Pmax during STS and VJ are unknown. This study aimed to determine the reliability and relationships of Pmax during VJ and STS assessments using a commercially designed testing device. Methods Sixteen healthy males (mean ± standard deviation: age, 24 ± 4 yr; height, 177 ± 7 cm; mass, 86 ± 19 kg) visited the laboratory on two occasions separated by 2–7 d. During each visit, participants performed three maximal STS tests from a table at knee flexions of 90° (STS90) and 120° (STS120) and three countermovement jumps (CMJ) and squat jumps (SJ) in randomized order. Reliability for Pmax during STS and VJ were determined using intraclass correlation coefficients (ICC; model 2,1) and standard errors of the mean (SEM). Systematic variability was examined using separate one-way repeated-measures analyses of variance (ANOVA). Pearson correlation coefficients (r) examined relationships between Pmax as measured during the STS and the VJ. Results ANOVA indicated no systematic variability in Pmax across trials (P > 0.05). ICC and SEM expressed as percentages of the mean ranged from 0.958 to 0.978 and 5.586% to 6.396% for STS and from 0.924 to 0.974 and 4.025% to 6.534% for VJ, respectively. Significant positive relationships were observed between Pmax as measured during STS90, STS120, CMJ, and SJ (r = 0.751–0.962, P ≤ 0.001). Conclusion Results indicate that commercially designed devices may be highly reliable for assessing Pmax during STS and VJ. STS testing is potentially an effective alternative to VJ for assessing lower-body muscle power.
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Oh, Seunghoon, Charles K. Abrams, Vytas K. Verselis, and Thaddeus A. Bargiello. "Stoichiometry of Transjunctional Voltage–Gating Polarity Reversal by a Negative Charge Substitution in the Amino Terminus of a Connexin32 Chimera." Journal of General Physiology 116, no. 1 (July 1, 2000): 13–32. http://dx.doi.org/10.1085/jgp.116.1.13.
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Gap junctions are intercellular channels formed by the serial, head to head arrangement of two hemichannels. Each hemichannel is an oligomer of six protein subunits, which in vertebrates are encoded by the connexin gene family. All intercellular channels formed by connexins are sensitive to the relative difference in the membrane potential between coupled cells, the transjunctional voltage (Vj), and gate by the separate action of their component hemichannels (Harris, A.L., D.C. Spray, and M.V. Bennett. 1981. J. Gen. Physiol. 77:95–117). We reported previously that the polarity of Vj dependence is opposite for hemichannels formed by two closely related connexins, Cx32 and Cx26, when they are paired to form intercellular channels (Verselis, V.K., C.S. Ginter, and T.A. Bargiello. 1994. Nature. 368:348–351). The opposite gating polarity is due to a difference in the charge of the second amino acid. Negative charge substitutions of the neutral asparagine residue present in wild-type Cx32 (Cx32N2E or Cx32N2D) reverse the gating polarity of Cx32 hemichannels from closure at negative Vj to closure at positive Vj. In this paper, we further examine the mechanism of polarity reversal by determining the gating polarity of a chimeric connexin, in which the first extracellular loop (E1) of Cx32 is replaced with that of Cx43 (Cx43E1). The resulting chimera, Cx32*Cx43E1, forms conductive hemichannels when expressed in single Xenopus oocytes and intercellular channels in pairs of oocytes (Pfahnl, A., X.W. Zhou, R. Werner, and G. Dahl. 1997. Pflügers Arch. 433:733–779). We demonstrate that the polarity of Vj dependence of Cx32*Cx43E1 hemichannels in intercellular pairings is the same as that of wild-type Cx32 hemichannels and is reversed by the N2E substitution. In records of single intercellular channels, Vj dependence is characterized by gating transitions between fully open and subconductance levels. Comparable transitions are observed in Cx32*Cx43E1 conductive hemichannels at negative membrane potentials and the polarity of these transitions is reversed by the N2E substitution. We conclude that the mechanism of Vj dependence of intercellular channels is conserved in conductive hemichannels and term the process Vj gating. Heteromeric conductive hemichannels comprised of Cx32*Cx43E1 and Cx32N2E*Cx43E1 subunits display bipolar Vj gating, closing to substates at both positive and negative membrane potentials. The number of bipolar hemichannels observed in cells expressing mixtures of the two connexin subunits coincides with the number of hemichannels that are expected to contain a single oppositely charged subunit. We conclude that the movement of the voltage sensor in a single connexin subunit is sufficient to initiate Vj gating. We further suggest that Vj gating results from conformational changes in individual connexin subunits rather than by a concerted change in the conformation of all six subunits.
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Weber, J. S., J. Berry, T. Manser, and J. L. Claflin. "Position of the rearranged V kappa and its 5' flanking sequences determines the location of somatic mutations in the J kappa locus." Journal of Immunology 146, no. 10 (May 15, 1991): 3652–55. http://dx.doi.org/10.4049/jimmunol.146.10.3652.
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Abstract Somatic hypermutation is known to occur in the VJ kappa exon and its flanking sequences, yet little is known about the hypermutation mechanism or its exact target within the rearranged locus. Mutations may occur at the same frequency, spanning a region from the leader intron to 3' of J kappa 5, regardless of which J is chosen for VJ rearrangement. Another possibility is that mutations may be limited to the rearranged VJ kappa and its immediate flanking sequences. To distinguish between these possibilities, the JC introns of 21 alleles with V kappa rearranged to J kappa 1 were sequenced, and mutations were located. The frequency of mutations was determined for different sections of the intron and compared with the frequencies of mutations found in the JC intron of a set of VJ kappa 5 alleles. The results showed that mutations were concentrated in and around the rearranged VJ, regardless of whether J kappa 1 or J kappa 5 was used. These data imply that the hypermutational mechanism focuses on rearranged V genes.
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Sales, Marcelo, Ana Maciel, Samuel Aguiar, Ricardo Asano, Daisy Motta-Santos, José Moraes, Polissandro Alves, et al. "Vertical Jump Is Strongly Associated to Running-Based Anaerobic Sprint Test in Teenage Futsal Male Athletes." Sports 6, no. 4 (October 25, 2018): 129. http://dx.doi.org/10.3390/sports6040129.
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As one of the most popular sport modalities in Brazil, and with an exponential growth in Europe, futsal is characterized by intermittent stimulus of anaerobic high intensity sprints. The running-based anaerobic sprint test (RAST) is one of the most common tests to assess anaerobic power in futsal athletes, however, it presents both time and physical challenges. Therefore, we aimed to correlate RAST with a simpler test, the vertical jump (VJ), in teenage male futsal athletes; Methods: Thirteen volunteers were enrolled and underwent two visits to the laboratory, one for the VJ and the other for the RAST in a randomized order; Results: The association test indicates a strong and significant correlation between VJ and RAST. We conclude that VJ can be used as an alternative to RAST in teenage male futsal athletes.
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Bechtel, Cale, Joshua A. Cotter, and Evan E. Schick. "Back Squat Potentiates Both Vertical and Horizontal Jump Performance in Collegiate Ice Hockey Players." International Journal of Kinesiology and Sports Science 6, no. 1 (January 31, 2018): 26. http://dx.doi.org/10.7575/aiac.ijkss.v.6n.1p.26.
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Background: Back squats (BSQ) have been shown to transiently improve performance in explosive vertical movements such as the vertical jump (VJ). Still, understanding of this phenomenon, termed post-activation potentiation (PAP), remains nebulous as it relates to explosive horizontal movements. Objective: Therefore, the purpose of the present investigation was to assess whether heavy BSQ can potentiate both VJ and horizontal jump (HJ) performance. Method: Nine male ice hockey players from the Long Beach State ice hockey team performed five testing sessions separated by 96-hours. The first testing session consisted of a one repetition maximum (1-RM) BSQ to determine subsequent testing loads. The four subsequent testing sessions, which were randomized for order, consisted of five repetitions of BSQ at 87% 1-RM followed by horizontal jump (BSQ-HJ), five repetitions of BSQ at 87% 1-RM followed by vertical jump (BSQ-VJ), horizontal jump only (CT-HJ) and vertical jump only (CT-VJ). During the potentiated conditions, rest intervals were set at five minutes between the BSQ and either VJ or HJ. Alpha-level was set a priori at 0.05. Results: The results indicate that both vertical (p=0.017) and horizontal (p=0.003) jump were significantly increased (VJ= +5.51cm, HJ= +11.55cm) following a BSQ. Conclusion: These findings suggest that BSQ may improve both vertical and horizontal jump performance in athletes who participate in sports emphasizing horizontal power, such as ice hockey.
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Neeb, Karl-Hermann, and Ivan Penkov. "Cartan Subalgebras of." Canadian Mathematical Bulletin 46, no. 4 (December 1, 2003): 597–616. http://dx.doi.org/10.4153/cmb-2003-056-1.
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AbstractLet V be a vector space over a field of characteristic zero and V* be a space of linear functionals on V which separate the points of V. We consider V ⊗ V* as a Lie algebra of finite rank operators on V, and set (V, V*) := V ⊗ V*. We define a Cartan subalgebra of (V, V*) as the centralizer of a maximal subalgebra every element of which is semisimple, and then give the following description of all Cartan subalgebras of (V;V*) under the assumption that is algebraically closed. A subalgebra of (V, V*) is a Cartan subalgebra if and only if it equals for some one-dimensional subspaces Vj ⊆ V and (Vj)* ⊆ V* with (Vi)* (Vj) = δij and such that the spaces . We then discuss explicit constructions of subspaces Vj and (Vj)* as above. Our second main result claims that a Cartan subalgebra of (V, V*) can be described alternatively as a locally nilpotent self-normalizing subalgebra whose adjoint representation is locally finite, or as a subalgebra h which coincides with the maximal locally nilpotent h-submodule of (V, V*), and such that the adjoint representation of is locally finite.
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Thomas, Christopher, Paul Comfort, Paul A. Jones, and Thomas Dos’Santos. "A Comparison of Isometric Midthigh-Pull Strength, Vertical Jump, Sprint Speed, and Change-of-Direction Speed in Academy Netball Players." International Journal of Sports Physiology and Performance 12, no. 7 (August 2017): 916–21. http://dx.doi.org/10.1123/ijspp.2016-0317.
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Purpose:To investigate the relationships between maximal isometric strength, vertical jump (VJ), sprint speed, and change-of-direction speed (CoDS) in academy netball players and determine whether players who have high performance in isometric strength testing would demonstrate superior performance in VJ, sprint speed, and CoDS measures.Method:Twenty-six young female netball players (age 16.1 ± 1.2 y, height 173.9 ± 5.7 cm, body mass 66.0 ± 7.2 kg) from a regional netball academy performed isometric midthigh pull (IMTP), squat jumps (SJs), countermovement jumps (CMJs), 10-m sprints, and CoDS (505).Results:IMTP measures displayed moderate to strong correlations with sprint and CoDS performance (r = –.41 to –.66). The VJs, which included SJs and CMJs, demonstrated strong correlations with 10-m sprint times (r = –.60 to –.65; P < .01) and CoDS (r = –.60 to –.71; P = .01). Stronger players displayed significantly faster sprint (ES = 1.1–1.2) and CoDS times (ES = 1.2–1.7) and greater VJ height (ES = 0.9–1.0) than weaker players.Conclusion:The results of this study illustrate the importance of developing high levels of lower-body strength to enhance VJ, sprint, and CoDS performance in youth netball players, with stronger athletes demonstrating superior VJ, sprint, and CoDS performances.
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Yates, Allison A., Joanne Holden, Susan Gebhardt, and Suzanne P. Murphy. "Reply to VJ Drake et al." American Journal of Clinical Nutrition 87, no. 4 (April 1, 2008): 1068–69. http://dx.doi.org/10.1093/ajcn/87.4.1068.
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Joseph, K. L. Vincent, Jonghun Lim, A. Anthonysamy, Hyoung-il Kim, Wonyong Choi, and Jin Kon Kim. "Squaraine-sensitized composite of a reduced graphene oxide/TiO2 photocatalyst: π–π stacking as a new method of dye anchoring." Journal of Materials Chemistry A 3, no. 1 (2015): 232–39. http://dx.doi.org/10.1039/c4ta04313h.
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We synthesized a near infra-red (NIR) absorbing squaraine dye (VJ-S) showing a strong absorption and emission. Photocatalytic activity of VJ-S/r-NGOT in visible light wavelengths is much higher than that of r-NGOT alone.
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Lipiński, Kamil. "The Fragmentary Narrative in the Nomadic VJ Performance by Peter Greenaway." Panoptikum, no. 19 (June 30, 2018): 108–20. http://dx.doi.org/10.26881/pan.2018.19.08.
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The article explores fragmentary, transmedia images of the nomadic Tulse Luper VJ Performance in terms of activation of the senses. Considering its key characteristics (such as mobility of the spectator, the multiplicity of viewpoints, fragmentary storytelling), this VJ screen-based performance challenges ordinary assumptions of the cinematic experience. This perspective sheds a new light on the areal connection of the multi-screen environment that exceeds the perception of one linear story in favour of a kaleidoscopic stream of images and ekphrastic writing. By analysing spatio-temporal specifics of the No TV Tulse Luper VJ Performance, this methodological study attempted to demonstrate that the VJ projection could not only be perceived as a reconfiguration of the basic trilogy but also as a unique, non-linear, touch-based manipulation of storytelling that aims at transforming a cinematic event into a real-time, expanded audiovisual project.
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Perez-Armendariz, E. M., M. C. Romano, J. Luna, C. Miranda, M. V. Bennett, and A. P. Moreno. "Characterization of gap junctions between pairs of Leydig cells from mouse testis." American Journal of Physiology-Cell Physiology 267, no. 2 (August 1, 1994): C570—C580. http://dx.doi.org/10.1152/ajpcell.1994.267.2.c570.
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Leydig cells are coupled in vivo by numerous gap junctions. In vivo and in vitro cells were immunolabeled by connexin 43 (Cx43) but not by Cx26 or Cx32 antibodies; immunoblotting confirmed specificity of Cx43 labeling. Pairs of Leydig cells dissociated from mouse testis were studied by dual whole cell voltage clamp, and a high incidence of dye (n = 20) and electrical coupling (n = 60; > 90%) was found. Coupling coefficients were near 1 and junctional conductance (gj) averaged 7.2 +/- 1.2 nS (SE, n = 40). Large transjunctional voltage (Vj) decreased gj; currents decayed exponentially with time constants of seconds that decreased at greater Vj. The residual conductance at large Vj was at least approximately 40% of the initial conductance. Exposure of cell pairs to saline solutions saturated with CO2 (n = 15) or containing 2 mM halothane (n = 15) or 3.5 mM heptanol (n = 15) rapidly and reversibly reduced gj. In eight cell pairs, gating of single junctional channels was observed during halothane-induced reduction in gj. Most gating events at Vj < 40 mV were fit by a Gaussian distribution with a mean of approximately 100 pS. With Vj > 40 mV, smaller transitions of approximately 30 pS were also recorded, and the frequency and duration of the approximately 100-pS transitions decreased. Also, approximately 70-pS transitions between 30- and 100-pS conductances were observed in the absence of 70-pS transitions to or from the baseline, indicating that the 30-pS conductance was a substate induced by large Vj.
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Saidi, Nur Fatihah, Chee Hian Tan, Raja Mohammed Firhad Raja Azidin, Hashbullah Ismail, Choo Yee Yu, and Geik Yong Yu. "ASSOCIATIONS BETWEEN SPEED, POWER AND ENDURANCE PERFORMANCE IN SUPER LEAGUE SOCCER PLAYERS." Malaysian Journal of Sport Science and Recreation 18, no. 2 (September 15, 2022): 150–60. http://dx.doi.org/10.24191/mjssr.v18i2.19553.
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The physical characteristics favourable for soccer players includes high level of speed, explosive jumping power, and aerobic fitness which highlights the importance of assessing these characteristics for strength and conditioning training program development. The aim of this study is to examine the associations between speed, power and endurance performance of Malaysia Super League soccer players. Twenty-four male soccer players (age = 24.50 ± 3.11 years, height = 176.12 ± 8.11 cm, body mass = 70.86 ± 9.07 kg) were recruited in this study and all the players were tested for explosive lower body power (vertical jump, VJ), speed (30meter sprint), and endurance (Yo-Yo Intermittent Endurance level 2, YYIEL2). A statistically significant correlation was found between 30-meter sprint time and distance covered in YYIEL2, but contrary to previous findings reported in the literature, sprint time and VJ height were not correlated. Therefore, VJ training may not necessarily improve speed and an improvement in VJ performance may not reflect an improvement in speed. In addition, no significant correlation was found between VJ height and the distance covered in YYIEL2. Given the intermittent nature of the game, the negative moderate correlation between sprint time and distance covered in YYIEL2 (r = -0.43, p <0.05) indicated that specific aerobic and anaerobic performance could be enhanced simultaneously through the appropriate training programme.
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Lu, Chengbiao, and Douglas G. McMahon. "Gap junction channel gating at bass retinal electrical synapses." Visual Neuroscience 13, no. 6 (November 1996): 1049–57. http://dx.doi.org/10.1017/s0952523800007707.
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AbstractTo further characterize the properties of retinal horizontal cell electrical synapses, we have studied the gating characteristics of gap junctions between cone-driven horizontal cells from the hybrid striped bass retina using double whole-cell voltage-clamp techniques. In a total of 105 cell pairs, the macroscopic conductance ranged from 0.4–100 nS with most cell pairs exhibiting junctional conductances between 10 and 30 nS. The junctional current-voltage relationship showed that peak or instantaneous currents (Iinst) were linear within the Vj range of ±100 mV and that steady-state junctional currents (Iss) exhibited rectification with increasing voltage beginning around ±30–40 mV Vj. The normalized junctional current-voltage relationship was well fit by a two-state Boltzmann distribution, with an effective gating charge of 1.9 charges/channel, a half-maximal voltage of approximately ±55 mV, and a normalized residual conductance of 0.28. The decay of junctional current followed a single exponential time course with the time constant decreasing with increasing Vj. Recovery of junctional current from voltage-dependent inactivation takes about 1 s following a pulse of 80 mV, and is about five times slower than the inactivation time course at the same Vj. Single-channel analysis showed that the unitary conductance of junctional channels is 50–70 pS. The overall open probability decreased in a voltage-dependent manner. Both the mean channel open time and the frequency of channel opening decreased, while the channel closure time increased. The ratio of closed time/total recording time significantly increased as Vj increased. Increased Vj reduced the number of events at all levels and shifted the unitary conductance to a lower level. Kinetic analysis of channel open duration showed that the distribution of channel open times was best fit by two exponentials and increased Vj significantly reduced the slower time constant. These results indicate that bass retina horizontal cells exhibit voltage-dependent inactivation of macroscopic junctional current. The inactivation occurs at the single-channel level mainly by increasing the rate of closure of voltage-sensitive channels.
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Sanova, Zoya. "The level of milk production jersey cows depending on genealogy." Agrarian Bulletin of the 204, no. 01 (March 13, 2021): 60–69. http://dx.doi.org/10.32417/1997-4868-2021-204-01-60-69.
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Abstract. The purpose of the research. Was to study the milk productivity and reproductive abilities of Jersey cows in the context of bulls and their fathers. Object of research. Cows, bulls-fathers of the Jersey breed in the breeding reproducer, data from the “Selex” program. Results and practical significance. The results of evaluating the use of Jersey bulls by a set of characteristics are shown. Indicators of daughters of some bulls-producers are given; milk productivity and reproductive qualities. A wide range of characteristics was evaluated – from milk productivity and reproductive qualities, to health indicators (milk yield coefficient, milk yield rate, and animal body weight (exterior). It is shown that there is a sufficient spread of productivity values in the herd for some indicators, the best are the daughters of some bulls, and for others, the daughters of others. The best bulls of VJ Lutz, VJ Hihl and DJ Hulk with productivity of daughters more than 6000 kg, as well as the worst bulls of Q Hirse and VJ Lurak with yields below 6000 kg were identified. The percentage of fat in milk (more than 6.0 %) was higher in the daughters of Q Hirse, VJ Lutz. The coefficient of dairy cows depending on the bulls-producers ranged from 1267 (father VJ Zdzhorup) to 1575 kg (father VJ Herodot). The conducted research will allow selection and selection of bulls and cows taking into account the genetic trend in generations, and regulate the level of intensity of the selection process in the population. Scientific novelty. Breeding work in cattle breeding Kaluga region is to increase breeding value and enhance the productive qualities of Jersey cattle. For the first time in the region, a comprehensive assessment of imported Jersey cows on productive, reproductive and technological characteristics was given.
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Litichevskiy, D. V. "PYRAMID SCHEME FOR CONSTRUCTING BIORTHOGONAL WAVELET CODES OVER FINITE FIELDS." Prikladnaya Diskretnaya Matematika, no. 51 (2021): 101–19. http://dx.doi.org/10.17223/20710410/51/5.
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The existence of a biorthogonal decomposition of the space V of dimension n over the field GF(q) is constructively proved, namely, two representations of it are obtained as direct sums of subspaces V = W0⊕W1⊕. . .⊕WJ⊕VJ and V = W˜0⊕W˜1⊕. . .⊕W˜J⊕V˜J ,such that at the j-th level of the decomposition, for 0 < j 6 J, Vj−1 = Vj⊕Wj , V˜j−1 == V˜j ⊕ W˜j , the subspace Vj is orthogonal to W˜j , and the subspace Wj is orthogonal to V˜j . The partition of the space at the j-th level is made with the help of pairs of level filters (hj, gj) and (h˜j, g˜j), for the construction of which the corresponding algorithms have been developed and theoretically proved. A new family of biorthogonal wavelet codes is built on the basis of the multilevel wavelet decomposition scheme with coding rate 2−L, where L is the number of used decomposition levels, and examples of such codes are given.
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Faigenbaum, Avery D., James E. McFarland, Neil A. Kelly, Nicholas A. Ratamess, Jie Kang, and Jay R. Hoffman. "Influence of Recovery Time on Warm-Up Effects in Male Adolescent Athletes." Pediatric Exercise Science 22, no. 2 (May 2010): 266–77. http://dx.doi.org/10.1123/pes.22.2.266.
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The purpose of this study was to examine the influence of recovery time following a dynamic warm-up (DY) and a static stretch warm-up (SS) on power performance in adolescent athletes. Following baseline measures, 19 males (16.5 ± 1.1 yrs) performed the vertical jump (VJ) and seated medicine ball toss (MB) at the following time points after DY and SS: 2, 6, 10, 14, 18, 22 min. Analysis of variance revealed that VJ was significantly greater following DY than SS at 2, 6, 10, 14 and 18 min. Main effects indicated a significant increase in VJ from baseline at 2 and 6 min following DY (2.6–3.9%) and a significant decrease in VJ from baseline at 2, 6, 10, 14 and 18 min following SS (–3.2% to –7.0%). No significant interaction effects between DY and SS were observed for MB. These findings indicate that lower body power performance in male adolescent athletes can be enhanced following DY as compared with SS during the first 18 min of the post warm-up period.
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SAMUEL, STUART. "ON THE SPEED OF GRAVITY AND THE JUPITER/QUASAR MEASUREMENT." International Journal of Modern Physics D 13, no. 09 (October 2004): 1753–70. http://dx.doi.org/10.1142/s0218271804005900.
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I present the theory and analysis behind the experiment by Fomalont and Kopeikin involving Jupiter and quasar J0842+1845 that purported to measure the speed of gravity. The computation of the vJ/c correction to the gravitational time delay difference relevant to the experiment is derived, where vJ is the speed of Jupiter as measured from Earth. Since the vJ/c corrections are too small to have been measured in the Jupiter/quasar experiment, it is impossible that the speed of gravity was extracted from the data, and I explain what went wrong with the data analysis. Finally, mistakes are shown in papers by Fomalont and Kopeikin intended to rebut my work and the work of others.
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Lin, Xianming, and Richard D. Veenstra. "Action potential modulation of connexin40 gap junctional conductance." American Journal of Physiology-Heart and Circulatory Physiology 286, no. 5 (May 2004): H1726—H1735. http://dx.doi.org/10.1152/ajpheart.00943.2003.
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Connexin40 (Cx40) is abundantly expressed in the atrial myocardium, ventricular conduction system, and vascular endothelial and smooth muscle cells of the mammalian cardiovascular system. Rapid conduction through cardiac tissues depends on electrotonic transfer of the action potential between neighboring cells. To determine whether transjunctional voltages ( Vj) elicited by an action potential can modulate conductance of Cx40 gap junctions, simulated myocardial action potentials were applied as voltage-clamp waveforms to Cx40 gap junctions expressed in mouse neuro2A (N2A) cells. Junctional currents resembled the action potential morphology but declined by >50% from peak to near-constant plateau values. Kinetics of Cx40 voltage gating were examined at peak voltages ≥100 mV, and decay time constants changed e-fold per 17.6 mV for Vj > ±40 mV. Junctional conductance recovered during phase 3 repolarization and early diastole to initial values. These phasic changes in junctional conductance were due to rapid decay kinetics, increasing to tens of milliseconds at peak Vj of 130 mV, and the increase in the steady-state conductance curve as Vj returned toward 0 mV. Time-dependent conductance curves for Cx40 were modeled with one inactivation and two recovery Vj-dependent components. There was a temporal correlation between development of conduction delay or block and the inactivation phase of junctional conductance. Likewise, recovery of junctional conductance was coincident with recovery from refractoriness, suggesting that gap junctions may play a role in the genesis and propagation of cardiac arrhythmias.
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Giustino, Valerio, Giuseppe Messina, Antonino Patti, Elvira Padua, Daniele Zangla, Patrik Drid, Giuseppe Battaglia, Antonio Palma, and Antonino Bianco. "Effects of a Postural Exercise Program on Vertical Jump Height in Young Female Volleyball Players with Knee Valgus." International Journal of Environmental Research and Public Health 19, no. 7 (March 26, 2022): 3953. http://dx.doi.org/10.3390/ijerph19073953.
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Background: Although a knee valgus position is related to the increase in injury risk in volleyball players, there is a lack of studies on the relationship between knee valgus and vertical jump (VJ) performance. Hence, the aim of this study was to investigate the effects of a postural exercise program on VJ height in young female volleyball players with knee valgus. Methods: This pilot study included 19 young female volleyball players divided into the following groups: the Valgus Experimental Group (VEG); the Valgus Control Group (VCG); and the Neutral Control Group (NCG). All three groups carried out the same volleyball training program. In addition, only the VEG underwent a 3-month postural exercise program of 30–45 min/session, twice/week. VJ performance was measured through the Sargent test before (T0), at 6 weeks (T1), and at 12 weeks (T2). Results: A significant effect from T0 to T1 (p = 0.0017) and from T0 to T2 (p = 0.0001) was found in the VEG. No significant differences were found over time in the VCG and in the NCG. Conclusion: An integrated postural exercise program might lead to a more balanced muscle efficiency inducing athletes to obtain a higher VJ performance.
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Moran, Patricia. "VJ em cena: espaços como partitura audiovisual." Revista Contracampo, no. 13 (December 1, 2005): 155. http://dx.doi.org/10.22409/contracampo.v0i13.505.
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Vamos discutir neste artigo projeções de imagens manipuladas ao vivo que funcionam como partituras audiovisuais. São cintilação: imagens figurativas e gráficas, pessoas dançando sob luzes estroboscópicas. Na noite, em boates, raves e galerias, a distribuição das telas no lugar e o excesso de luzes coloridas criam o espaço-experiência, o espaço-estímulo, criam projeções-espaço. O espaço de estímulos aqui proporcionados promove uma experiência imersiva que se aproxima de outros dispositivos com imagens-espaço, como os ambientes dos videogames e da realidade virtual interativa. Por outro lado, deles se afastam por se constituírem de imagens-luz, de imagens cintilantes figurativas ou não, enfim, por se estruturarem como partituras audiovisuais.
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Augustsson, Sofia Ryman. "Maximum Strength in Squats Determines Jumping Height in Young Female Volleyball Players." Open Sports Sciences Journal 6, no. 1 (August 20, 2013): 41–46. http://dx.doi.org/10.2174/1875399x01306010041.
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Few data exist on the relationship between maximum strength and power performance, such as jumping ability in low-level female volleyball players. The aim of the present study was to determine the relationship between maximum strength and jumping performance in young female non-elite volleyball players before and after an in-season resistancetraining protocol. A 26-week, in-season resistance-training program was carried out on ten female volleyball players, aged 19 (±2). The 1 RM squat test was used to evaluate the players’ maximum strength in the lower extremities and a vertical jump (VJ) test was used to assess functional performance and power. There was a significant enhancement of 69% (p=0.005) for the squat test and 9% for the VJ test (p=0.008). A strong significant relationship was found between the VJ test and the 1 RM squat test (r=0.68, r2=0.47, p=0.0014) at the pre-test and post-test (r=0.88, r2=0.77, p=0.001). When comparing the coefficients of correlation (r=0.68 and r=0.88) between the squat tests and VJ tests, the difference that was noted was significant (p<0.001). A strong significant relationship was also noted between the 1RM squat and VJ test relative to body weight at pre-test (r=0.89, r2=0.79, p=0.001) and post-test (r=0.95, r2=0.90), p<0.001). This study demonstrates that maximum strength in squats is a major predictive factor for jumping height in young female volleyball players. Female volleyball players might therefore consider focusing on maximum strength training to improve their jumping performance.
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Veenstra, R. D. "Voltage-dependent gating of gap junction channels in embryonic chick ventricular cell pairs." American Journal of Physiology-Cell Physiology 258, no. 4 (April 1, 1990): C662—C672. http://dx.doi.org/10.1152/ajpcell.1990.258.4.c662.
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The dependence of macroscopic gap junctional conductance (Gj) on transjunctional voltage (Vj) was studied in paired myocytes after enzymatic dissociation of 7-day-old embryonic chick ventricles. The membrane voltage of both cells was independently controlled by separate patch-clamp circuits in the whole cell configuration. Two distinctive unitary junctional conductances were identified in recordings from seven different cell pairs. The larger channel had a mean conductance of 166 +/- 37 pS (n = 6 pairs), whereas a second channel averaged 58 +/- 10 pS (n = 3). Instantaneous Gj remained linear over a Vj range of -100 to +100 mV, whereas the steady-state Gj declined when voltages exceeded +/- 30 mV. Both decay and recovery phases of Gj follow exponential time courses, with the recovery time constant being four times slower than inactivation, requiring 1.1 s at 80 mV. The normalized steady-state Gj-Vj curve could be defined by a two-state Boltzmann distribution, assuming an effective gating charge of 1.72, a half-inactivation voltage of 45 mV, and a residual voltage-insensitive Gj of 27% of maximum. Single-channel recordings revealed closure of 160-pS channels on a Vj step to 80 mV, and the ensemble average of five such records produced an exponentially decaying junctional current with a time constant of 184 ms. The single-channel current-voltage relationship remains linear with a slope of 145 pS over the entire Vj range. The results support the hypothesis that a population of 160-pS gap junction channels is gated by transjunctional potentials.
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Abreu, Frederico, Vera Zymbal, and Fátima Baptista. "Musculoskeletal Fitness for Identifying Low Physical Function in Older Women." International Journal of Environmental Research and Public Health 20, no. 8 (April 12, 2023): 5485. http://dx.doi.org/10.3390/ijerph20085485.
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Aims: This cross-sectional study aimed to analyze the relevance of musculoskeletal fitness for identifying low physical functioning in community-dwelling older women. Methods: Sixty-six older women (73.62 ± 8.23 yrs old) performed a musculoskeletal fitness assessment of the upper and lower limbs. A handheld dynamometer was used to evaluate upper-limb muscle strength through a handgrip (HG) test. Lower-limb power and force were assessed from a two-leg countermovement vertical jump (VJ) on a ground reaction force platform. Physical functioning was assessed subjectively using the Composite Physical Function (CPF) questionnaire and objectively by daily step count measured by accelerometry and gait speed/agility assessed by the 8-Foot Up-and-Go (TUG) test. Logistic regressions and ROC curves were carried out, aiming to define odds ratios and ideal cutoff values for discriminatory variables. Results: VJ power showed the ability to identify low physical functioning when evaluated through the CPF (14 W/kg, 1011 W), gait speed/agility (15 W/kg, 800 W), or daily accumulated steps (17 W/kg). Considering that VJ power was normalized for body mass, the increase of 1 W/kg corresponds to a decrease of 21%, 19%, or 16% in the chance of low physical functioning when expressed by these variables, respectively. HG strength and VJ force did not show a capacity to identify low physical functioning. Conclusions: The results suggest that VJ power is the only marker of low physical functioning when considering the three benchmarks: perception of physical ability, capacity for mobility, and daily mobility.
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K A, Harikrishnan, and Manilal K. "On open neighborhood energy of graphs." Gulf Journal of Mathematics 15, no. 1 (August 18, 2023): 119–30. http://dx.doi.org/10.56947/gjom.v15i1.1122.
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The open neighborhood of a vertex u denoted by N(u) in a simple connected graph G is the collection of all vertices other than u and adjacent to u. In this paper, we introduce a square matrix of order n, called the open neighborhood matrix, ONM(G) of a graph G whose (i, j)th entry is |N(vi) ∩ N(vj)|/(di+dj) whenever vi~vj, i≠ j; and zero otherwise, where di and dj, are the degrees of vi and vj respectively. We then establish the relationship between the connectedness of the graph G and the multiplicity of the eigenvalue zero of the matrix ONM(G), if it exists. Furthermore, we found the bounds for the largest open neighbourhood eigenvalue and open neighbourhood energy of graphs.
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Lee, Jong-Tak. "Development of User's Evaluation Criteria for VJ Broadcasting Program." Journal of the Korea Contents Association 10, no. 5 (May 28, 2010): 135–43. http://dx.doi.org/10.5392/jkca.2010.10.5.135.
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Luebbers, Paul E., Matthew J. Andre, Andrew C. Fry, Luke A. Olsen, Keith B. Pfannestiel, and Dimitrije Cabarkapa. "Hormonal Responses and Jump Performance Across a Season in Collegiate Women Basketball Players." Women in Sport and Physical Activity Journal 30, no. 1 (April 1, 2022): 18–26. http://dx.doi.org/10.1123/wspaj.2021-0048.
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The testosterone-to-cortisol ratio (T/C) has been shown to be positively correlated with strength and power. However, few studies have examined the relationship between a standardized power performance measurement and T/C throughout a season of intercollegiate competition. The purpose of this study was to examine the relationships between salivary T/C and vertical jump (VJ) performance of female National Collegiate Athletic Association Division II basketball players across a season. Saliva samples were taken before practice, weekly, for a total of 29 weeks. Samples were assayed for testosterone (T) and cortisol (C). After saliva collection, players completed two countermovement VJs, with the best jump used for data analysis. A positive correlation between T/C and VJ was seen only during the preseason phase. Statistically significant differences were observed across the season for T/C and VJ. T/C in the nonconference phase was significantly lower than the preseason phase and the late-conference phase, p = .013 and p = .047, respectively. VJ was significantly lower in the late-conference phase when compared to the preseason and nonconference phases, p < .001 and p = .026, respectively. VJ in the early-conference phase was also significantly lower than the preseason phase, p < .001. These data support the literature that has indicated a positive relationship between the T/C and lower-body power but only in the preseason phase. This relationship reverses and trends toward a negative relationship, before disappearing in the second half of the season. Monitoring T/C may provide value in assessing female athletes’ performance potential in the preseason phase. T/C should be interpreted with more caution once the competitive season begins.
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Chanson, M., K. J. Chandross, M. B. Rook, J. A. Kessler, and D. C. Spray. "Gating characteristics of a steeply voltage-dependent gap junction channel in rat Schwann cells." Journal of General Physiology 102, no. 5 (November 1, 1993): 925–46. http://dx.doi.org/10.1085/jgp.102.5.925.
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The gating properties of macroscopic and microscopic gap junctional currents were compared by applying the dual whole cell patch clamp technique to pairs of neonatal rat Schwann cells. In response to transjunctional voltage pulses (Vj), macroscopic gap junctional currents decayed exponentially with time constants ranging from < 1 to < 10 s before reaching steady-state levels. The relationship between normalized steady-state junctional conductance (Gss) and (Vj) was well described by a Boltzmann relationship with e-fold decay per 10.4 mV, representing an equivalent gating charge of 2.4. At Vj > 60 mV, Gss was virtually zero, a property that is unique among the gap junctions characterized to date. Determination of opening and closing rate constants for this process indicated that the voltage dependence of macroscopic conductance was governed predominantly by the closing rate constant. In 78% of the experiments, a single population of unitary junctional currents was detected corresponding to an unitary channel conductance of approximately 40 pS. The presence of only a limited number of junctional channels with identical unitary conductances made it possible to analyze their kinetics at the single channel level. Gating at the single channel level was further studied using a stochastic model to determine the open probability (Po) of individual channels in a multiple channel preparation. Po decreased with increasing Vj following a Boltzmann relationship similar to that describing the macroscopic Gss voltage dependence. These results indicate that, for Vj of a single polarity, the gating of the 40 pS gap junction channels expressed by Schwann cells can be described by a first order kinetic model of channel transitions between open and closed states.
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Maia, Carlos Vangerre de Almeida, Anny Kariny Feitosa, Vanessa Sandyla da Silva Rocha, Renata Saraiva Vidal, and Tiago Regis de Melo Alves. "Reflexões sobre a cobrança pelos serviços de gestão dos resíduos sólidos em municípios cearenses consorciados." DRd - Desenvolvimento Regional em debate 9 (October 29, 2019): 668–82. http://dx.doi.org/10.24302/drd.v9i0.2226.
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O Plano Estadual de Resíduos Sólidos do Ceará (PERSCE) determina que, até 2020, 20% dos seus municípios estejam consorciados e realizem cobrança pelos serviços de manejo de resíduos sólidos desvinculadamente do Imposto Predial Territorial Urbano (IPTU). O Consórcio de Gestão Integrada de Resíduos Sólidos – Vale do Jaguaribe (CGIRS-VJ) operará equipamentos de transbordo, transporte e disposição final por meio da iniciativa privada, cujo dispêndio poderá ser repassado aos usuários. Esse trabalho verificou se as variáveis sugeridas para a possível base de cálculo da cobrança do serviço na região estão entre as mais usuais; e comparou indicadores socioeconômicos dos entes do CGIRS-VJ (Grupo I) com de outros municípios igualmente consorciados e que já realizem a cobrança dessa maneira (Grupo II). Através do Sistema Nacional de Informações sobre Saneamento, identificou-se quais os municípios brasileiros estão consorciados e realizam a cobrança de maneira desvinculada do IPTU. As variáveis que compõem as bases de cálculo foram consultadas nas legislações municipais. Constatou-se que as variáveis sugeridas para compor a base de cálculo dos entes do CGIRS-VJ estão entre as mais recorrentes e há diferença significativa entre as médias do IDH e do PIB per capita dos integrantes do CGIRS-VJ, inferiores às médias dos municípios do Grupo II.
Palavras-chave: Sustentabilidade. Indicadores. Consórcios públicos.
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Fonseca, Renato Tavares, Gustavo Casimiro Lopes, Juliana Brandão Pinto de Castro, Luciano Alonso Valente dos Santos, Bruno Lucas Pinheiro Lima, Gilson Ramos de Oliveira Filho, Rodolfo de Alkmim Moreira Nunes, and Rodrigo Gomes de Souza Vale. "Analysis of vertical jump, rating of perceived exertion, delayed-onset muscle soreness, and muscular peak power in young male Brazilian football players submitted to plyometric and semi-squat training with weights." Retos 46 (August 9, 2022): 613–21. http://dx.doi.org/10.47197/retos.v46.94085.
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This study analyzed the effects of plyometric and strength training on vertical jump (VJ), rating of perceived exertion (RPE), delayed-onset muscle soreness (DOMS), and absolute (APP) and relative (RPP) muscle peak power in young male football players. Twenty-five participants were randomly divided into semi-squat training group (SSTG), plyometric training group (PTG), and control group (CG). The duration of the intervention was six weeks. VJ was analyzed with a computerized jumping platform. DOMS and RPE with the Borg’s Visual Analogue Scale (VAS) and the Adapted Borg Scale (ABS), respectively. The SSTG showed improvements (p < 0.05) in countermovement jump (CMJ), squat jump (SJ), APP (3190.67 ± 338.49 W), and RPP (47.75 ± 5.01 W/kg). PTG showed improvements (p < 0.05) in SJ. In the intragroup comparations, SSTG, PTG, and CG showed an increase (p < 0.05) in RPE and DOMS. Between groups, PTG presented an increase (p < 0.05) on RPE and DOMS compared with SSTG and CG. CMJ presented strong correlations between APP and VJ, RPP, and VJ, and APP and RPP. SJ showed a higher positive correlation between all the physical variables. Only SSTG promoted an increase in both types of jumps, with a greater APP and RPP and a lower RPE and DOMS.
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López-Riquelme, Germán Octavio, Elia E. Soto-Alba, Carlos Ricardo Mata-Bautista, and Rachid Marzoug. "Jugar videojuegos de estrategia en tiempo real tiene efectos positivos en la memoria de trabajo." Revista ConCiencia EPG 7, Edición especial (April 9, 2022): 143–75. http://dx.doi.org/10.32654/concienciaepg/eds.especial-7.
Full textAbstract:
Los videojuegos de estrategia en tiempo real (VJ-ETR) requieren que los jugadores planeen estrategias reclutando capacidades cognitivas como atención, habilidades motoras, habilidades visuoespaciales y memoria de trabajo (MT). Ya que jugar VJ-ETR depende del mantenimiento de metas principales y submetas activas, así como de la revisión dinámica de esas metas conforme la situación lo requiere, el objetivo de este trabajo fue estudiar si jugadores expertos de VJ-ETR (JExp-ETR) tienen una mayor capacidad de MT que no-jugadores (No-ETR). Para ello, comparamos el desempeño entre JExp-ETR y No-ETR en MT y velocidad de procesamiento (VP) empleando el Wechsler Adult Intelligence Scale (WAIS-IV) y la tarea n-back. Los resultados muestran que los JExp-ETR tienen un mayor índice de MT y una mejor precisión en el n-back que los No-ETR, principalmente en el 3-back, pero no encontramos diferencias en VP. Además, también encontramos que los JExp-ETR que juegan más horas a la semana tienen un mayor índice de MT que los JExp-ETR que juegan menos horas. Los resultados son discutidos en el marco de la capacidad de la MT, la importancia de los VJ-ETR y sus efectos en la cognición.
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Lockie, Robert G., Farzad Jalilvand, Corrin A. Jordan, Samuel J. Callaghan, Matthew D. Jeffriess, Tawni M. Luczo, and Adrian B. Schultz. "The Relationship between Unilateral Dynamic Stability and Multidirectional Jump Performance in Team Sport Athletes." Sport Science Review 24, no. 5-6 (December 1, 2015): 321–44. http://dx.doi.org/10.1515/ssr-2015-0022.
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AbstractThis study investigated relationships between dynamic stability and multidirectional jumping. A modified Star Excursion Balance Test (mSEBT), incorporating unilateral lower-body reaching in posteromedial, medial, and anteromedial directions, assessed dynamic stability. Unilateral vertical (VJ), standing broad (SBJ) and lateral jumps (LJ) assessed leg power. VJ power and relative SBJ and LJ distances were calculated. Thirty-two team sport athletes completed the mSEBT when each leg was used for stance, and left- and right-leg VJ, SBJ, and LJ. Correlations were drawn between data recorded from each leg when used for mSEBT stance and for each jump. Participants were dichotomized into better and lesser dynamic stability groups according to the sum of excursions for each leg. A one-way ANOVA determined mSEBT and jump differences (p< 0.05). The left-leg posteromedial and medial excursions correlated with VJ power; the medial excursion correlated with the LJ. The right-leg posteromedial excursion correlated with the SBJ; the anteromedial excursion correlated with the SBJ, and relative SBJ and LJ (r = 0.35-0.45). There were no differences in unilateral jumping between the better and lesser groups. Although there is some relationship with dynamic stability, this study further highlighted the complex interaction between the physical and technical characteristics of multidirectional jumping.
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Lockie, Robert G., Ashley J. Orjalo, Victoria L. Amran, Deshaun L. Davis, Fabrice G. Risso, and Farzad Jalilvand. "An introductory analysis as to the influence of lower-body power on multidirectional speed in collegiate female rugby players." Sport Science Review 25, no. 1-2 (May 1, 2016): 113–34. http://dx.doi.org/10.1515/ssr-2016-0007.
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AbstractThis study investigated relationships between lower-body power, measured by a vertical jump (VJ) and standing broad jump (SBJ), with multidirectional speed in collegiate female rugby players. The rugby player data was compared to that of general team sport athletes to ascertain whether there were characteristics specific to collegiate rugby players. Multi-directional speed was measured by a 20-meter (m) sprint (0-5, 0-10, 0-20 m intervals) and 505 change-of-direction speed test. Eight rugby players and eight team sport athletes completed all tests. Spearman’s correlations calculated relationships between the VJ and SBJ with the speed tests, and stepwise multiple regressions determined whether the jump tests predicted speed performance (p≤ 0.05). For the rugby players, the VJ correlated with the 0-20 m interval (r = −0.73). The SBJ correlated with the 0-5 and 0-10 m intervals, and the left-leg 505 (r = −0.71 to −0.88), and predicted 0-5 m and left-leg 505 time (r2= 0.50-0.58). For the team sport athletes, only the VJ correlated with left-leg 505 (r = −0.80), and predicted left- and right-leg 505 times (r2= 0.61-0.69). The results suggest that horizontal power measured by a SBJ has a greater contribution to multidirectional speed in collegiate female rugby players.
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Gerodimos, Vassilis, Andreas Zafeiridis, Stefanos Perkos, Konstantina Dipla, Vassiliki Manou, and Spiros Kellis. "The Contribution of Stretch-Shortening Cycle and Arm-Swing to Vertical Jumping Performance in Children, Adolescents, and Adult Basketball Players." Pediatric Exercise Science 20, no. 4 (November 2008): 379–89. http://dx.doi.org/10.1123/pes.20.4.379.
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This study examined from childhood to adulthood: (1) the effects of countermovement (use of stretch-shortening cycle-SSC) and arm-swing (AS) on vertical jumping (VJ) performance and (2) the ability to use the SSC and AS during VJ. Male basketball players (n = 106) were divided according to their age into: children (12.0 ± 0.23), young adolescents (14.5 ± 0.41), old adolescents (16.9 ± 0.27), and adults (21.9 ± 0.32). Each participant executed three maximal squat jumps (SJ), countermovement jumps without arms (CMJ) and with arms (CMJA). The contribution of SSC and AS was calculated by the augmentation (difference and percent change) in performance between CMJ and SJ, and CMJA and CMJ, respectively. CMJA performance was significantly (p < .05) higher than CMJ and SJ, and CMJ was higher than SJ within all age-groups. There were no significant differences (p > .05) among children, young and old adolescents, and adults in the percent contribution of SSC and AS to VJ performance. The variability in the contribution of SSC and AS to VJ performance was about twofold higher in children vs. adults. It appears that the ability to use the SSC and AS is not affected by the maturation process in males, trained in basketball.
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Thalavayalil, Timmy Tomy, and Sudev Naduvath. "A study on coarse deg-centric graphs." Gulf Journal of Mathematics 16, no. 2 (April 12, 2024): 171–82. http://dx.doi.org/10.56947/gjom.v16i2.1877.
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The coarse deg-centric graph of a simple, connected graph G, denoted by Gcd, is a graph constructed from G such that V(Gcd) = V(G) and E(Gcd) = {vi vj : dG( vi, vj) > degG(vi)}. This paper introduces and discusses the concepts of coarse deg-centric graphs and iterated coarse deg-centrication of a graph. It also presents the properties and structural characteristics of coarse deg-centric graphs of some graph families.
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Mondal, Sourav, and Kinkar Chandra Das. "Degree-Based Graph Entropy in Structure–Property Modeling." Entropy 25, no. 7 (July 21, 2023): 1092. http://dx.doi.org/10.3390/e25071092.
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Graph entropy plays an essential role in interpreting the structural information and complexity measure of a network. Let G be a graph of order n. Suppose dG(vi) is degree of the vertex vi for each i=1,2,…,n. Now, the k-th degree-based graph entropy for G is defined as Id,k(G)=−∑i=1ndG(vi)k∑j=1ndG(vj)klogdG(vi)k∑j=1ndG(vj)k, where k is real number. The first-degree-based entropy is generated for k=1, which has been well nurtured in last few years. As ∑j=1ndG(vj)k yields the well-known graph invariant first Zagreb index, the Id,k for k=2 is worthy of investigation. We call this graph entropy as the second-degree-based entropy. The present work aims to investigate the role of Id,2 in structure property modeling of molecules.
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Panoutsakopoulos, Vassilios, Mariana C. Kotzamanidou, Athanasios K. Giannakos, and Iraklis A. Kollias. "Relationship of Vertical Jump Performance and Ankle Joint Range of Motion: Effect of Knee Joint Angle and Handedness in Young Adult Handball Players." Sports 10, no. 6 (May 28, 2022): 86. http://dx.doi.org/10.3390/sports10060086.
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The purpose of the study is to examine the effect of the ankle joint range of motion (ROM) on the vertical jump (VJ) performance of adult handball players. The active (ACT) and passive (PAS) ankle joint ROM of 12 male members of the U21 National Handball Team with the knee joint at 0°, 40°, and 90° flexion (0° = fully extended knee) was evaluated using a video analysis measuring method. Participants also performed maximum VJ with (CMJ) and without (SQJ) countermovement, as well as with (AS) and without (NAS) an arm swing. Statistical analyses included 2 × 2 × 3 MANOVA, 2 × 2 repeated measures ANOVA, and Pearson’s correlation. Results reveal that PAS-ROM was larger (p < 0.05) in all knee joint flexion angles. ROM was smaller (p < 0.05) by approximately 10° at 0° compared to 90° knee flexion. No lateral effects on ROM due to the handedness of the players were observed. AS and CM resulted in increased jump height (p < 0.05). Finally, ACT-ROM when the knee joint was flexed at 40° was highly correlated (r ≥ 0.66, p < 0.05) with VJ performance except for CMJ-AS. In conclusion, the differences in the bi-articular gastrocnemius muscle flexibility due to the alteration of the angular position of the examined joints affected the ability to generate impulse during the VJ tests.
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Chulvi-Medrano, Iván, Manuel Pombo, Miguel Ángel Saavedra-García, Tamara Rial Rebullido, and Avery D. Faigenbaum. "A 47-Year Comparison of Lower Body Muscular Power in Spanish Boys: A Short Report." Journal of Functional Morphology and Kinesiology 5, no. 3 (August 20, 2020): 64. http://dx.doi.org/10.3390/jfmk5030064.
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Much of the evidence examining temporal trends in fitness among youth has found a decrease in measures of muscular strength and muscular power over recent decades. The aim of this study was to examine trends in lower body muscular power in Spanish boys over 47 years. In 1969 140 boys (10–11 years; body mass index = 19.24, SD = 2.91 kg/m2) and in 2016, 113 boys (10–11 years; body mass index = 19.20, SD = 3.15 kg/m2) were recruited. Lower body power was assessed using the vertical jump (VJ) and standing long jump (SLJ) tests. Significant differences and a large effect size were shown between groups in the SLJ (p = 0.001; d = 0.94) and the VJ (p = 0.001; d = 0.66). SLJ data in 1969 were higher (1.52 m, SD = 0.19) when compared to the 2016 data (1.34 m, SD = 0.18). The VJ performance of the 1969 sample was also higher (25.95 cm; SD = 6.58) than the 2016 sample (21.56 cm; SD = 4.72). SLJ and VJ performance of the 2016 group decreased 11.8% and 16.9%, respectively. There were no significant differences between groups in body mass index. The results indicate a secular decline in lower body muscular power in 10–11-year-old Spanish boys with no significant changes in body mass index over the 47-year study period.
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Cornara, Laura, Gabriele Ambu, Domenico Trombetta, Marcella Denaro, Susanna Alloisio, Jessica Frigerio, Massimo Labra, Govinda Ghimire, Marco Valussi, and Antonella Smeriglio. "Multidisciplinary Screening of Three Species belonging to Caprifoliaceae Family Traditionally Used as Antidepressants." Biology and Life Sciences Forum 4, no. 1 (December 1, 2020): 2. http://dx.doi.org/10.3390/iecps2020-08643.
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The essential oils (EOs) of the Eurasiatic Valeriana officinalis (Vo), the Himalayan Valeriana jatamansi (Vj) and Nardostachys jatamansi (Nj), are traditionally used to treat neurological disorders. A multidisciplinary approach based on micromorphology, DNA barcoding, EOs characterization as well as evaluation of the biological effects on the nervous system was carried out. Nj showed the highest inhibitory activity on acetylcholinesterase (IC50 67.15 μg/mL), followed by Vo (IC50 127.30 μg/mL) and Vj (IC50 246.84 μg/mL). Microelectrode arrays analyses on rat cortical neurons revealed stronger inhibition by Nj (IC50 18.8 and 11.1 μg/mL) and Vo (16.5 and 22.5 μg/mL), compared with Vj (68.5 and 89.3 μg/mL). These results could be related to the different EOs composition and in particular to the different content of oxygenated compounds such as aldehydes and ketones, which represents a discriminating factor in determining the order of potency. In conclusion, this multidisciplinary approach could be a useful tool to quickly discriminate these three plant species and avoid adulterations.