Reduction In Variables Research Articles

Effects of a Very Low-Carbohydrate High-Fat Diet and High-Intensity Interval Training on Visceral Fat Deposition and Cardiorespiratory Fitness in Overfat Individuals: A Randomized Controlled Clinical Trial.

Purpose: This randomized controlled parallel-group study examined the effects of a very low-carbohydrate high-fat (VLCHF) diet and high-intensity interval training (HIIT) program over 12 weeks on visceral adipose tissue (VAT) and cardiorespiratory fitness (CRF) level in overfat individuals.Methods: Ninety-one participants were randomly allocated to the HIIT (N = 22), VLCHF (N = 25), VLCHF+HIIT (N = 25), or control (N = 19) groups for 12 weeks. Body composition and CRF were analyzed before the experimental period and after 4, 8, and 12 weeks. Dual-energy X-ray absorptiometry (DXA) and graded exercise test (GXT) to volitional exhaustion were used for the body composition and CRF assessments, respectively.Results: There were significant between-group differences in the VAT mass and body composition outcome changes. VAT mass decreased after 12 weeks only in the VLCHF and VLCHF+HIIT groups (p < 0.001, median [95% CI]: VLCHF: −142.0 [−187.0; −109.5] g; VLCHF+HIIT: −104.0 [−135.0; −71.0] g). Similarly, changes in body mass, total body fat, trunk fat mass, waist and hip circumferences were distinctly decreased in the VLCHF and VLCHF+HIIT groups, when compared to HIIT and Control groups. Total lean mass significantly decreased in the VLCHF and VLCHF+HIIT groups (−2.1 [−3.0; −1.6] kg and −2.5 [−3.6; −1.8] kg, respectively) after 12 weeks. While the HIIT program significantly increased total time to exhaustion in the GXT, peak oxygen uptake was unchanged.Conclusions: A VLCHF diet, either in isolation or in combination with HIIT, was shown to induce a significant reduction in VAT mass and body composition variables. HIIT alone did not cause such effects on body composition, but improved exercise capacity. Our findings indicate that the VLCHF diet and exercise training provoked different and isolated effects on body composition and CRF.Clinical Trial Registration: https://clinicaltrials.gov/ct2/show/NCT03934476, identifier: NCT03934476.

Hypoglycemic and hypolipidemic properties of Casuarina equisetifolia leaf extracts in alloxan induced diabetic rats

BackgroundCausarina equisetifolia is a plant used traditionally as a remedy for various disorders such as diabetes, hyperlipidemia, gastric problems and muscle weakness. The aqueous, ethanol and methanol extracts of C. equisetifolia leaves were studied for hypoglycemic and hypolipidemic potentials. MethodologyPhytochemical analysis was carried out using standard procedures. Rats of both sexes, weighing (145–255 g) were randomly allotted to six groups with each group having four rats. Rats in group A were the normoglycemic, while those in groups B, C, D, E, and F were rendered diabetic by the administration of 110 mg/kg bodyweight of alloxan monohydrate. Group C rats were treated with 15 mg/kg bodyweight of standard drug (Glidazide), while groups D, E, and F rats were respectively treated with 150 mg/kg bodyweight of aqueous, ethanol, and methanol extracts for 15 days. The group B rats were untreated (negative control). Blood glucose was checked after every three days using glucometer. At the end of the treatment, the rats were anaesthetized under chloroform vapor and blood samples were collected by jugular puncture and used for analyzing biochemical parameters. ResultsExtracts showed presence of tannins, flavonoids, saponins, phenols, alkaloids and reducing sugars. There was 64%, 59% and 58% reduction in blood glucose concentration of diabetic rats treated with ethanol, aqueous, methanol extracts respectively. Serum cholesterol and triacylglycerol of the three treated groups reduced (p < 0.05) with the aqueous and methanol extract treated groups having the most significant reductions in both variables (147.93±8.04, 152.91±10.85 mg/dL) when compared with the diabetic group (203.21±6.45, 355.16±11.25 mg/dL) respectively. AST and ALP activities reduced significantly (p < 0.05) in the aqueous extract treated group (33.18±4.48, 52.60±7.23 u/L) with no significant differences when values were compared to that of the normal control group (25.64±4.18, 44.13±5.80 u/L) respectively. Urea concentration decreased in all extract treatment groups except the group treated with the aqueous extract. Creatinine also decreased in the extract treated groups apart from the group treated with the aqueous and methanol extracts when both compared with the normal control group. ConclusionThe extracts from the leaves of C. equisetifolia have hypoglycemic and hypolipidemic effects, and can be further explored as a natural novel lead for drug development in the management of diabetes and dyslipidemia.

Relationship between physical activity, objective sleep parameters, and circadian rhythm in patients with head and neck cancer receiving chemoradiotherapy: A longitudinal study.

ObjectivesThis study was developed to assess the relationship between physical activity, sleep and circadian rhythm using accelerometer and urine melatonin levels in patients with head and neck cancer (HNC). Also, this study evaluated the changes in physical activity, sleep, and circadian rhythm during the seven‐week course of chemoradiotherapy.MethodsThis longitudinal study recruited 27 participants diagnosed with HNC who were planning to undergo chemoradiotherapy. Accelerometers worn for 3 days during the 1st, 3rd, and 7th weeks of chemoradiotherapy were used to assess physical activity levels (step count and metabolic equivalents [METs]) and sleep quality (total sleep time [TST], sleep onset latency [SOL], and sleep efficiency [SE]). Urine melatonin analysis was conducted using the morning void urine sample on 1st, 3rd, and 7th weeks. The change in variables during the seven weeks and the correlation between them were analyzed.ResultsDuring the seven weeks, trends of reduction in variables of physical activity, sleep and circadian rhythm were observed with significant decrease in step count, TST and melatonin levels. SE was found to have strong negative correlation with physical activity. TST was found to have moderate correlation with SE and step count. The variables of physical activity also showed moderate correlation among them.ConclusionThis study concludes that higher physical activity is associated with poor SE due to increased night‐time activity. There was a significant reduction in physical activity and sleep observed during seven weeks with moderate association between them. The significant circadian rhythm deregulation however showed poor association with the other variables.Level of Evidence: 2b

The Study of Usefulness of a Set of Fractal Parameters to Build Classes of Disease Units Based on Images of Pigmented Skin Lesions.

Dermatoscopic images are also increasingly used to train artificial neural networks for the future to provide fully automatic diagnostic systems capable of determining the type of pigmented skin lesion. Therefore, fractal analysis was used in this study to measure the irregularity of pigmented skin lesion surfaces. This paper presents selected results from individual stages of preliminary processing of the dermatoscopic image on pigmented skin lesion, in which fractal analysis was used and referred to the effectiveness of classification by fuzzy or statistical methods. Classification of the first unsupervised stage was performed using the method of analysis of scatter graphs and the fuzzy method using the Kohonen network. The results of the Kohonen network learning process with an input vector consisting of eight elements prove that neuronal activation requires a larger learning set with greater differentiation. For the same training conditions, the final results are at a higher level and can be classified as weaker. Statistics of factor analysis were proposed, allowing for the reduction in variables, and the directions of further studies were indicated.

Improved Workflow for Fault Detection and Extraction Using Seismic Attributes and Orientation Clustering

Faults represent important analytical targets for the identification of perceptual ground motions and associated seismic hazards. In particular, during oil production, important data such as the path and flow rate of fluid flows can be obtained from information on fault location and their connectivity. Seismic attributes are conventional methods used for fault detection, whereby information obtained from seismic data are analyzed using various property processing methods. The analyzed data eventually provide information on fault properties and imaging of fault surfaces. In this study, we propose an efficient workflow for fault detection and extraction of requisite information to construct a fault surface model using 3D seismic cubes. This workflow not only improves the ability to detect faults but also distinguishes the edges of a fault more clearly, even with the application of fewer attributes compared to conventional workflows. Thus, the computing time of attribute processing is reduced, and fault surface cubes are generated more rapidly. In addition, the reduction in input variables reduces the effect of the interpreter’s subjective intervention on the results. Furthermore, the clustering method can be applied to the azimuth and dip of the fault to be extracted from the complexly intertwined fault faces and subsequently imaged. The application of the proposed workflow to field data obtained from the Vincentian oil field in Australia resulted in a significant reduction in noise compared to conventional methods. It also led to clearer and continuous edge detection and extraction.

Potassium nutrition as a strategy to mitigate salt stress in melon grown under protected cultivation

The use of saline water is one of the major challenges of agriculture, as it can cause nutritional imbalances and thus reduce crop yield. This study proposes to examine the efficiency of potassium nutrition as a salt stress-mitigating agent in melon grown in a protected environment. The experiment was laid out in a randomized-block design with ten treatments in a 2 × 4 factorial arrangement represented by two melon cultivars (McLaren and SV1044MF) and four nutrient solutions (S1 - standard nutrient solution, 2.5 dS m-1; S2 - nutrient solution salinized with NaCl, 5.0 dS m-1; S3 - nutrient solution salinized with NaCl + 50% K, 6.5 dS m-1; and S4 - nutrient solution salinized with NaCl + 100% K, 7.5 dS m-1). Yield (average fruit weight, production, fruit diameter, internal cavity, and pulp thickness), quality (pulp firmness, total sugars, soluble solids [SS], vitamin C, pH, titratable acidity [TA] and SS/TA ratio) and nutritional (K, Na and K/Na ratio) variables were evaluated. Plants fertigated with standard nutrient solution showed the highest values for fruit weight (1,190.6 g), production (2,381.3 g per plant), fruit diameter (13.6 cm) and pulp thickness (2.6 cm). Cultivar McLaren produced heavier fruits (931.4 g) with larger diameter (12.4 cm) and pulp thickness (2.4 cm). The addition of NaCl to nutrient solution induced a reduction in the yield variables but did not influence fruit quality. The addition of extra K to salinized nutrient solution did not mitigate the deleterious effect of salinity on the yield of melon.

A Comparative Study of a Novel Postural Garment Versus Exercise for Women with Nonspecific Cervical Pain: A Randomized Cross-over Trial.

Randomized cross-over study. The aim of this study was to compare exercise, the criterion standard, to the postural garment PosturePlusForce in the management of nonspecific cervical pain in women. We also analyzed both interventions with regards to baseline posture, use of pharmacological pain relievers, compliance, and comfort. The prevalence of neck pain has increased during the last decade, preferentially affecting women. Those suffering from this condition may manifest a decrease in quality of life and inability to work. Consistent recommendations highlight the importance of exercise and posture for neck pain improvement. A total of 32 female health care professionals with cervical pain (≥3 on the visual analogue scale) entered the trial. Participants were allocated to either performing exercises or wearing the postural garment. The cross-over between interventions was separated by a 3-month washout period. Primary outcomes included pain intensity and posture. Secondary outcomes comprised cervical pain-related disability, psychological factors, physical activity, global perceived effect of treatment, and garment comfort. Treatment compliance, medication use, and adverse events were also recorded. Both interventions showed a significant improvement in pain in subjects with an adherence >60%. However, in participants with dorsal hyperkyphosis (>45°), the garment demonstrated a greater reduction in pain than exercise (P = 0.019). Additionally, those wearing the garment needed fewer pain relievers than those performing exercises (P = 0.007). Compliance was >50% for both interventions and comfort was contingent on season. In our study, PosturePlusForce showed, at least, a similar effect on pain to exercise, although those with dorsal hyperkyphosis exhibited a greater reduction in pain and related variables with the garment. Pain relievers were less required by those wearing PosturePlusForce than by those performing the exercises.Level of Evidence: 1.

Disease severity and ecophysiology of rootstock/scion combinations of different avocado (Persea americana Mill.) genotypes in response to laurel wilt

Laurel wilt, caused by the fungus Raffaelea lauricola, is a lethal vascular disease that affects many members of the Lauraceae family, including avocado (Persea americana Mill.) trees. Previous studies have shown differences in laurel wilt susceptibility among genotypes, with cultivars of the West Indian (WI) race generally more susceptible to laurel wilt than Guatemalan (G) or Mexican (M) race cultivars. We conducted four experiments to compare susceptibility and ecophysiological responses to laurel wilt among scion/rootstock combinations from the different botanical races. In the first two experiments, clonally propagated ‘Simmonds’ (WI) scion grafted on ‘Waldin’ (WI), ‘Reed’ (G) or ‘Duke 7’ (M) rootstock (Experiment 1), or grafted on ‘Waldin’, ‘Nabal’ (G) or ‘Zutano’ (M) rootstock (Experiment 2) were compared. In the other two experiments, ‘Waldin’, ‘Reed’ or ‘Duke 7’ scion grafted on ‘Duke 7’ rootstock (Experiment 3), or ‘Reed’ rootstock (Experiment 4) were compared. For each scion/rootstock combination, trees were divided into two treatments: inoculated with R. lauricola, or 2) inoculated with deionized water as a control. Disease severity in all trees was determined daily using a rating scale based on the percentage of visible symptoms. Net CO2 assimilation (A), stomatal conductance of water vapor (gs), the daily xylem sap flow rate, and the ratio of variable to maximum chlorophyll fluorescence (Fv/Fm) in leaves were determined three times per week until one or more scion/rootstock combination in the laurel wilt treatment showed severe symptoms. Trees from each treatment were then harvested and stem sections observed for browning of the sapwood (a characteristic laurel wilt symptom), and plated on a selective medium to recover the fungus if present. Raffaelea lauricola was recovered in all trees in the laurel wilt treatment and no trees in the control treatment. Laurel wilt susceptibility varied among the scion/rootstock combinations. Trees in the laurel wilt treatment with ‘Simmonds’ as the scion developed more symptoms and exhibited a greater reduction in physiological variables than the control trees, regardless of the genotype of the rootstock. ‘Duke 7’, either as the scion or rootstock, inoculated with the laurel wilt pathogen had less disease development and less of a reduction in physiological variables than the other genotypes. The results indicate that there are differences in laurel wilt susceptibility among grafted avocado cultivars of different genotypes. These difference may be related to the botanical race of the scion and/or the rootstock.

English

In the present study, fifteen cucumber genotypes were screened against Zucchini yellow mosaic virus (ZYMV) and root-knot nematode (Meloidogyne incognita) individually and in combinations. All the cucumber genotypes behaved differently regarding root and shoot lengths and weights, number of galls, eggmasses and ZYMV infection when inoculated with M. incognita and ZYMV alone and in combinations. None of the fifteen cucumber genotypes was found immune, highly or moderately resistant to M. incognita. Two genotypes viz., Alpha Prime and Patio were found resistant to the nematode. Contrarily, Max Pack and Beti-alpha were highly susceptible as evident by maximum galls on their roots and reductions in growth variables. Similarly, the genotypes Best PIC, Songrooh, Northern Pack, C-7 and C-5 appeared as moderately susceptible whereas Shaheen, Jakson, C-1, C-2, C-3 and C-9 genotypes showed susceptible reactions to the nematode alone. Similar trend was noticed when the genotypes were inoculated with both the nematode and the virus. Similarly, on the basis of disease rating scale, two genotypes viz., Alpha Prime and Patio were grouped as moderately resistant to ZYMV. On the other hand, eleven genotypes viz., Max Pack, Shaheen, Songrooh, Northern Pack, Jakson, Beti-alpha, C-1, C-2, C-3, C-5 and C-9 were catalogued as highly resistant while two genotypes Best PIC and C-7 were categorized as susceptible against ZYMV alone. Similarly, all the genotypes behaved in the same way when inoculated with M. incognita. Two genotypes Alpha Prime and Patio were found resistant against both the pathogens inoculated simultaneously and hence are recommended for cultivation. © 2021 Friends Science Publishers

Mechanical pruning and soil organic amendments in vineyards of Syrah: effects on grape composition

Aim: The interaction of mechanized pruning systems and soil organic amendment can increase vine productivity. However, since the increase in productivity may affect grape composition, this study aimed to understand the effects of the interaction between these two practices.Methods and materials: Two field trials were implemented in Shiraz vineyards in two different wine regions. Mechanical hedge pruning was compared with hand spur pruning and four different organic amendments were tested: biochar, municipal solid waste compost, cattle manure and sewage sludge.Results: Mechanical pruning reduced the total soluble solids (TSS) and pH of the grapes, but had no effects on the other variables. Organic amendments also reduced TSS, especially sewage sludge, and tended to reduce total anthocyanins and total phenols. The effect of the interaction between both factors on grape composition was never significant. A negative relationship between yield and TSS was observed, while titratable acidity had no relationship with yield. Total anthocyanins were also negatively related to yield. A positive relation between TSS and total anthocyanins was also observed.Conclusions: The results show that the combination of mechanical pruning and soil organic amendment is a powerful tool for increasing productivity, but it has some effects on grape composition.Significance and impact of study: The reduction in some fruit composition variables showed that, while mechanical pruning does not significantly affect grape composition, the choice of type and amount of organic amendment will depend on the destination of the grapes.

Changes in Neuromuscular Status Across a Season of Professional Men's Ice Hockey.

Gannon, EA, Higham, DG, Gardner, BW, Nan, N, Zhao, J, and Bisson, LJ. Changes in neuromuscular status across a season of professional men's ice hockey. J Strength Cond Res 35(5): 1338-1344, 2021-To quantify changes in neuromuscular function over a full professional men's ice hockey season, 27 players (n = 18 forwards and 9 defensemen) performed 3 countermovement jumps (CMJ) each week over 30 sessions separated into 4 phases: preseason, early-season, midseason, and late-season. Outcome variables represented jump performance (jump height), kinematics (mean velocity and peak velocity), and movement strategy (countermovement depth). Mixed models characterized relationships between positional group, season phase, and CMJ outcomes. Statistical significance was set at p ≤ 0.05. Concentric peak velocity (p = 0.02), jump height (p = 0.001), and countermovement depth (p < 0.001) displayed a significant reduction across the season. Peak velocity was lower during the early-season than the preseason (-0.10 ± 0.06 m·s-1, mean change ± 95% confidence limit, p = 0.05). Countermovement depth was reduced during the early-season (-0.06 ± 0.03 m, p = 0.02), midseason (-0.10 ± 0.04 m, p = 0.002), and late-season (-0.15 ± 0.04 m, p < 0.001) relative to the preseason. Reductions in CMJ variables from preseason to in-season ranged from trivial to large. Changes in countermovement depth differed for forwards and defensemen by the season phase (p = 0.04). A professional ice hockey season decreases CMJ performance, with the effects of fatigue most prominent during the late-season phase. Countermovement depth was most sensitive to fatigue and differentiated positional-group responses. Frequent CMJ testing is useful for identifying the neuromuscular status of team-sport athletes relative to season-specific phases. Fatigue monitoring should incorporate movement-strategy variables alongside traditional measures of performance and kinematics.

Quantification of arterial, venous, and cerebrospinal fluid flow dynamics by magnetic resonance imaging under simulated micro-gravity conditions: a prospective cohort study

BackgroundAstronauts undergoing long-duration spaceflight are exposed to numerous health risks, including Spaceflight-Associated Neuro-Ocular Syndrome (SANS), a spectrum of ophthalmic changes that can result in permanent loss of visual acuity. The etiology of SANS is not well understood but is thought to involve changes in cerebrovascular flow dynamics in response to microgravity. There is a paucity of knowledge in this area; in particular, cerebrospinal fluid (CSF) flow dynamics have not been well characterized under microgravity conditions. Our study was designed to determine the effect of simulated microgravity (head-down tilt [HDT]) on cerebrovascular flow dynamics. We hypothesized that microgravity conditions simulated by acute HDT would result in increases in CSF pulsatile flow.MethodsIn a prospective cohort study, we measured flow in major cerebral arteries, veins, and CSF spaces in fifteen healthy volunteers using phase contrast magnetic resonance (PCMR) before and during 15° HDT.ResultsWe found a decrease in all CSF flow variables [systolic peak flow (p = 0.009), and peak-to-peak pulse amplitude (p = 0.001)]. Cerebral arterial average flow (p = 0.04), systolic peak flow (p = 0.04), and peak-to-peak pulse amplitude (p = 0.02) all also significantly decreased. We additionally found a decrease in average cerebral arterial flow (p = 0.040). Finally, a significant increase in cerebral venous cross-sectional area under HDT (p = 0.005) was also observed.ConclusionsThese results collectively demonstrate that acute application of −15° HDT caused a reduction in CSF flow variables (systolic peak flow and peak-to-peak pulse amplitude) which, when coupled with a decrease in average cerebral arterial flow, systolic peak flow, and peak-to-peak pulse amplitude, is consistent with a decrease in cardiac-related pulsatile CSF flow. These results suggest that decreases in cerebral arterial inflow were the principal drivers of decreases in CSF pulsatile flow.

Reproductive parameters of lambs immunocastrated with anti-GnRH vaccine.

The objective of this study was to evaluate the testicular biometric, seminal, and plasma testosterone levels in lambs subjected to an anti-GnRH vaccine as a method of castration. Thirty entire, crossbred Santa Inês male lambs were randomly distributed into three treatment (T): T1 was the control group, with the administration of 1 mL of saline solution subcutaneously (SC); 1.0 and 0.5 mL of an anti-GnRH vaccine were administered SC in T2 and T3, respectively. Testicular biometric variables, physical and morphological variables of semen, and plasma testosterone concentrations were evaluated. At D60, there was a reduction in testicular length, width, thickness, and scrotal circumference of the immunocastrated animals regardless of the vaccine dose used (P < 0.05). A reduction in semen physical variables at both dosages (P < 0.05) was observed, with azoospermia, in 80% and 70% of animals in the T2 and T3 groups, respectively. At D60, the immunocastrated animals also showed an increase in spermatozoa defects (P < 0.05), whereas plasma testosterone concentration decreased (P < 0.05). Immunocastration of lambs using the Bopriva vaccine at doses of 1.0 and 0.5 mL is efficient in inducing azoospermia in up to 80% of animals, although two doses in a 30-day interval are necessary for it to be an effective and safe method. Efficacy was demonstrated through a reduction in serum testosterone levels, testicular biometry, and seminal fluid analysis. Considering the efficacy of both doses in this study, we recommend using the lower dose (0.5 mL), which will allow for a 50% reduction in vaccine costs.

Large Reductions in Match Play Physical Performance Variables Across a Professional Football Season With Control for Situational and Contextual Variables.

This investigation examined match play physical performance across a professional football season using a multicamera computerized tracking system. A linear mixed-effects model, controlling for situational and contextual variables, identified decreases in team average total distance (TD): season quarter 1 (Q1) (11,047 m) > season quarter 2 (Q2) (10,473 m) (P = 0.002; ES = Small), season quarter 3 (Q3) (10,449 m) (P < 0.001; ES = Moderate), and season quarter 4 (Q4) (10,385 m) (P < 0.001; ES = Moderate); work rate (WR): Q1 (115 m/min) > Q3 (108 m/min) (P < 0.001; ES = Moderate), Q4 (107 m/min) (P < 0.001; ES = Moderate); Q2 (109 m/min) > Q4 (107 m/min) (P = 0.003; ES = Small); high-speed running distance (HSR): Q1 (1,051 m) > Q2 (813 m) (P = 0.006; ES = Small); number of high-speed runs (NHSR): Q1 (87) > Q2 (65) (P < 0.001; ES = Small), Q3 (64) (P = 0.002; ES = Small); sprint distance (SD): Q1 (202 m) > Q4 (130 m) (P < 0.001; ES = Moderate), Q2 (179 m) > Q3 (165 m) (P = 0.035; ES = Small), Q4 (130 m) (P < 0.001; ES = Moderate) and number of sprints (NS): Q1 (20.4) > Q3 (10.2) (P < 0.001; ES = Moderate), Q4 (8.3) (P < 0.001; ES = Large); Q2 (14.9) > Q3 (10.2) (P < 0.001; ES = Moderate), Q4 (8.3) (P < 0.001; ES = Large). Within-position changes were observed for WR: Q1 (122 m/min) > Q4 (113 m/min) (P = 0.002; ES = Large) in central midfielders and for NS: Q1 > Q3 in wide defenders (21.7 vs. 10.8) (P = 0.044; ES = Large) and central midfielders (18.1 vs. 8.3) (P = 0.002; ES = Large); Q1 > Q4 in central defenders (13.1 vs. 5.3) (P = 0.014; ES = Large), wide defenders (21.6 vs. 7.1) (P < 0.001; ES = Very Large), central midfielders (18.1 vs. 8.5) (P = 0.005; ES = Large), and wide midfielders (20.8 vs. 12.2) (P = 0.012; ES = Large); Q2 > Q3 in central midfielders (16.9 vs. 8.3) (P = 0.002; ES = Large) and Q2 > Q4 in wide defenders (16.3 vs. 7.1) (P = 0.005; ES = Very Large), central midfielders (16.9 vs. 8.5) (P = 0.004; ES = Large), and wide midfielders (20.8 vs. 12.2) (P = 0.007; ES = Large). The match-play physical performance was reduced across the competitive season. The most notable reductions were observed in wide defenders, central midfielders, and wide midfielders in sprint performance indices.

A Prime-Logarithmic Method for Optimal Reliability Design

Optimal reliability design (ORD) problem is challenging and fundamental to the study of system reliability. For a system with $n$ components/stages where each of them can be set in $m$ possible reliability levels, state-of-the-art linear reformulation models of ORD problem require $O(nm)$ binary variables, $O(m^n)$ continuous variables together with either $O(m^n)$ inequality constraints or $O(nm)$ equality constraints. Using the special property of prime factorization and adopting the logarithmic expression technique, in this article, we propose a novel linear reformulation model of the ORD problem requiring $O(nm)$ binary variables, $O(\frac{m^n}{n!})$ continuous variables, and very few linear constraints. This theoretic reduction in variables and constraints can lead to significant savings in computational efforts. Our numerical experiments further confirm the drastic reduction in computational time for solving ORD problems in large size.

Effect of rainfall variability on the production of Vigna unguiculata (L.) Walp. in the semi-arid region of Paraíba

Agricultural production in semi-arid areas of the globe is dependent on species adapted to conditions of low availability of resources, such as water. Cowpea (Vigna unguiculata L. Walp.) is a vegetable widely grown in regions with water restrictions, however, even with its good adaptability, it is vulnerable to the effects of prolonged droughts. In this sense, this research aimed to analyze the influence of rainfall patterns on the production dynamics of cowpea during the period of fifteen years (2002-2016) in the municipality of Conceição, Paraíba, Brazil. A correlation matrix was used to analyze the influence of precipitation on the production variables of the cowpea crop, as well as the relationship between these variables. Subsequently, the Principal Component Analysis (PCA) was carried out. The results showed a strong reduction in the production variables of cowpea from the year 2012, which is due to the reduction of rainfall in this period and was proven through the correction matrix, which showed a positive correlation of rainfall mainly with the planted and harvested area. The PCA recorded 91.02% of explanation in the first two axes, and demonstrated that for production and productivity, other factors in addition to good rainfall levels are necessary to increase the productive results of cowpea in the municipality.

Parâmetros lineares da marcha de crianças com paralisia cerebral do tipo espástica: estudo de caso

INTRODUÇÃO: A paralisia cerebral (PC) ocorre devido lesão no sistema nervoso central, resultando em comprometimento funcional e alterações na marcha. OBJETIVO: verificar e descrever as variáveis lineares da marcha de crianças com paralisia cerebral do tipo espástica. MATERIAIS E MÉTODOS: participaram do estudo três crianças com idade entre seis e sete anos com paralisia cerebral do tipo espástica, GMFCS nível I e II, onde foi realizada a identificação do desempenho da função motora grossa por meio do Sistema de Classificação da Função Motora Grossa (GMFSC) com grau 3 e 4 de espasticidade em membros inferiores segundo a Escala Modificada de Ashworth (MAS). Para registro dos parâmetros lineares e organização dos dados foram utilizados o software livre CVMob e o método de análise de movimento MED - Movement Element Decomposition. RESULTADOS: Os valores encontrados para velocidade foram (0,64; 0,58; 0,96 m/s) comprimento do passo (0,34;0,36; 0,36 m) cadência (127; 118; 130 p/min). CONCLUSÃO: Foi verificada a diminuição das variáveis lineares da marcha para velocidade, comprimento do passo e cadência nas três crianças estudas. Apesar da dificuldade em obter amostra maior, os dados sugerem a necessidade de maior controle das variáveis da marcha de crianças com Paralisia cerebral do tipo espástica.

Could myocardial viability be related to left ventricular dyssynchrony? Simultaneous evaluation by gated SPECT-MPI

BackgroundLeft ventricular contraction dyssynchrony (LVCD) has been related to induced ischemia and transmural scar but the interplay of myocardial viability and dyssynchrony is unknown. The aim of the present study was to establish the role of dyssynchrony in the context of a viability study performed with nitrate augmentation gated single photon emission computed tomography (GSPECT) myocardial perfusion imaging (MPI). MethodsFifty-four consecutive patients with ischemic dilated cardiomyopathy (IDC) and depressed left ventricular ejection fraction (LVEF) were included. They underwent a two-day rest/nitroglycerine (NTG) study GSPECT MPI to determine the myocardial viability. Patients with a nitrate-induced uptake increase of > 10% vs baseline, in at least, two consecutive dysfunctional segments were considered viable as well as those who showed no improvement in the uptake but the uptake was > 50% on post NTG study. Patients with no nitrate-induced uptake increase of > 10% and the uptake of < 50% were considered non-viable. Perfusion, function and LVCD were compared in 25 viable patients vs 29 non-viable patients at baseline and after NTG administration. ResultsAfter NTG administration, in the viable group, the LVEF increased (36.44 ± 6.64% vs 39.84 ± 6.39%) and the end-systolic volume decreased significantly (119.28 ± 31.77 mL vs 109.08 ± 33.17 mL) (P < 0.01). These patients also experienced a significant reduction in the LVCD variables: phase standard deviation was reduced in the post NTG study (57.77° ± 19.47° vs 52.02° ± 17.09°) as well as the phase histogram bandwidth (190.20° ± 78.83° vs 178.0° ± 76.14°) (P < 0.05). Functional and LVCD variables remained similar in the non-viable patients (P > 0.05). ConclusionIn patients with IDC and depressed LVEF, the myocardial viability detected by rest/ NTG GSPECT MPI, might determine LVCD improvement.

Effect of plateletpheresis on total platelet count and mean platelet volume: A meta-analysis.

Currently, there are discrepancies in the reports on the extent of the reduction in platelet count after platelet donation by apheresis, and its impact on mean platelet volume (MPV). This study was conducted to meta-analyze the effect of plateletpheresis on platelet count and on mean platelet volume, based on studies published between 1980 and 2018. Medline-Pubmed, Scielo, ScienceDirect, and Scopus databases were searched from inception to December 31 2019. The PRISMA guidelines, reproducibility, and evaluation of the methodological quality were guaranteed. Heterogeneity was evaluated with DerSimonian-Laird's, publication bias with a Begg's test. Sensitivity analysis and cumulative meta-analysis were also conducted, as well as a forest plot. Twenty-five studies with 3769 donors were systematized to analyze platelet count, and seven studies with 1176 donors to observe MPV. Most studies were published in India and the United States. There was a postprocedure reduction in both variables. The reduction in platelet count was 14.3×103 /μL (95% CI 11.4 to 17.1×103 ⁄μL). The reduction in MPV was 1.43 fL (95% CI 0.3 to 2.5 fL). The analysis of subgroups showed that, in the case of platelet count, the reduction is not statistically significant two weeks after donation. Platelet donation by apheresis reduces platelet count and MPV in donors, which is detrimental to the purposes of the procedure; although the decrease is not clinically significant for the donor or the recipient. This demonstrates the need for subsequent studies to evaluate variables, such as donation frequency and donation intervals, should be considered to evaluate if the reported decrease is easily compensated, without adverse consequences for donors, or if modifications in donor selection criteria are required.

Root biomass and production of cotton cultivars subjected to saline water irrigation

Water scarcity and high levels of salinity in irrigation water limit irrigated cotton cultivation in the semiarid region of Northeast Brazil. So, it is necessary to adopt cultivation strategies that make the production system feasible. In this context, the present study aimed to evaluate the biomass and production of cotton cultivars subjected to different levels of saline water irrigation. The experiment was carried out under greenhouse conditions, with treatments distributed in a completely randomized design, in a 5 x 2 factorial arrangement, corresponding to five levels of irrigation water electrical conductivity - ECw (1.5, 3.0, 4.5, 6.0 and 7.5 dS m-1) and two cotton cultivars (BRS 368 RF and BRS Safira), with 4 replicates. Treatment effects were measured by the number of bolls per plant, lint weight, number of seeds per plant, total weight of seeds and dry and fresh biomass of stem, roots and leaves. Irrigation using water with electrical conductivity from 1.5 dS m-1 negatively affects the production of the cotton cultivars BRS SAFIRA and BRS 368 RF, causing reductions in all production variables analyzed. The cultivar BRS Safira has better production performance than BRS 368 RF when exposed to water salinity.