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AISI-1080 eutectoid steel is a low-cost material, which is widely used in several industries, including machinery parts and tools. However, surface modifications are necessary to upgrade the mechanical and tribological properties. Common heat treatments for surface modification of eutectoid steel are reported in the literature. In this work, the cathodic cage plasma deposition (CCPD) technique consisting of a titanium cathodic cage is used to deposit a titanium nitride (TiN) coating on eutectoid steel, and noteworthy improvement in surface properties is obtained. The effect of sample biasing and gas composition (nitrogen–hydrogen) on surface properties is examined. The cathodic samples exhibit iron nitrides (Fe2N, Fe4N) with minor TiN phases, and, at floating potential, the sample contains iron nitrides (Fe3N, Fe4N) and TiN phases. The hardness is upgraded to 1100 HV0.25 when the samples are treated at floating potential with higher hydrogen contents, much higher than the hardness reported by other treatments. The wear volume obtained by the micro-abrasive wear test is reduced after the coating deposition, and the lowest wear volume is obtained at floating potential with higher hydrogen contents (10-2 mm3), whereas the untreated sample exhibits wear volume (42 × 10−2 mm3). This study suggests that, instead of conventional heat treatments with a high temperature and extended treatment time, CCPD TiN deposition at floating potential with optimum gas composition is much more advantageous for eutectoid steel's hardness and wear resistance. [ABSTRACT FROM AUTHOR]

The expansion and potential rupture of the swim bladder due to rapid decompression, a major cause of barotrauma injury in fish that pass through turbines and pumps, is generally assumed to be governed by Boyle's Law. In this study, two swim bladder expansion models are presented and tested in silico. One based on the quasi-static Boyle's Law, and a Modified Rayleigh Plesset Model (MRPM), which includes both inertial and pressure functions and was parametrised to be representative of a fish swim bladder. The two models were tested using a range of: (1) simulated and (2) empirically derived pressure profiles. Our results highlight a range of conditions where the Boyle's Law model (BLM) is inappropriate for predicting swim bladder size in response to pressure change and that these conditions occur in situ, indicating that this is an applied and not just theoretical issue. Specifically, these conditions include any one, or any combination, of the following factors: (1) when rate of pressure change is anything but very slow compared to the resonant frequency of the swim bladder; (2) when the nadir pressure is near or at absolute zero; and (3) when a fish experiences liquid tensions (i.e. negative absolute pressures). Under each of these conditions, the MRPM is more appropriate tool for predicting swim bladder size in response to pressure change and hence it is a better model for quantifying barotrauma in fish. [ABSTRACT FROM AUTHOR]

Sillenites have been a subject of increasing interest for electronics applications due to their unique crystal structure, ease of synthesis and vast potential for combination with other elements. In this study, bismuth–cobalt-based material is produced and applied as microstrip patch antenna (MPA) substrate. Synthesis, characterization, simulations and measurements are detailed. To produce Bi13Co11, a sol–gel technique modified by ionic coordination reaction (ICR) was performed, followed by calcination and sintering. Structural characterization was performed by x-ray diffraction, followed by Rietveld refinement, resulting in a main phase-weighted percentage of 53.82%, to which the magnetic property of the material was ascribed. Dielectric characterization from 1.0 GHz to 8.5 GHz presented real permittivity around 5.0 and dielectric loss tangent around 0.02. Material performance as substrate was evaluated through two microstrip patch antenna geometries. Reflection coefficient (S11) measurements presented dual-band characteristics, good agreement with simulations and maximum resonance frequency error of 4.84%, validating characterizations. Directional behavior was observed through simulated radiation patterns. Efficiency ranged from 75% to 85% in all cases. [ABSTRACT FROM AUTHOR]

Youths living in crowded impoverished urban areas face higher risk of infection by SARS-CoV-2. This article presents lessons learned from a preventive intervention project intersected by the COVID-19 crisis that moved from a mix-methods study design to online ethnography. The 'home-officed' research team e-witnessed high-school students' daily lives and collaborated in youths' and community-based organisations' responses in the territories where they study and live. Psychosocial distress increased, also driven by the disastrous governmental response to the health and economic crises. There was growing anxiety about meeting friends and dating, with structural limits for sustaining the recommended social distancing, which added to gender/sexuality-based violence. Simultaneously, we observed students becoming relevant actors through co-producing preventive practices, surpassing risk-group notions and combining SARS-CoV-2 prevention with sexuality, gender, racism and mental-health issues. They managed internet-mediated applications to promote critical thinking and collective actions aimed at health promotion among their peers, from their homes. Freire's concept of 'untested-feasibility' fostered researchers', students' and community leaders' imaginations in the face of this unprecedented crisis, thereby enhancing social responses to the epidemic to become rights-based comprehensive dialogical preventive activities. This ongoing intervention-research stresses how prevention sciences can go beyond reduction of this pandemic to a viral event. [ABSTRACT FROM AUTHOR]

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Worldwide, fishways are increasingly criticized for failing to meet conservation goals. We argue that this is largely due to the dominance of diadromous species of the Northern Hemisphere (e.g., Salmonidae) in the research that underpins the concepts and methods of fishway science and management. With highly diverse life histories, swimming abilities and spatial ecologies, most freshwater fish species do not conform to the stereotype imposed by this framework. This is leading to a global proliferation of fishways that are often unsuitable for native species. The vast majority of fish populations do not undertake extensive migrations between clearly separated critical habitats, yet the movement of individuals and the genetic information they carry is critically important for population viability. We briefly review some of the latest advances in spatial ecological modelling for dendritic networks to better define what it means to achieve effective fish passage at a barrier. Through a combination of critical habitat assessment and the modelling of metapopulations, climate change‐driven habitat shifts, and adaptive gene flow, we recommend a conceptual and methodological framework for fishway target‐setting and monitoring suitable for a wide range of species. In the process, we raise a number of issues that should contribute to the ongoing debate about fish passage research and the design and monitoring of fishways. [ABSTRACT FROM AUTHOR]

Several artificial colouring agents are used as food additives to improve the foods' visual appearance. A recent increase in the use of natural colouring with bioactive properties (antioxidants) as a substitute for additives used in the food industry has led to the search for novel sources to produce such substances with functional colouring. The present work was aimed to isolate and select yeasts from the Cerrado (Savannah) biome (Central region, Brazil) to produce carotenoids. Sixty-nine of the 470 colonies, selected after screening, presented colours from yellow to red. These yeasts were grouped into three colours: yellow, pink and orange. Yeast belonging to the pink group, identified as Rhodotorula toruloides, was chosen for improvement of the factors (physical and nutritional) involved in submerged cultivation. Carotenoid bioproduction was improved by using an experimental design which evaluated the characteristics of the physical processes (agitation and temperature), followed by 25-1 factorial experimental design to select the relevant factors for the culture medium. Following statistical analysis, a complete second-order experimental design was employed to optimise the composition of the culture medium. The maximum carotenoid production obtained was 1,333.11 μg.L-1 (106.92 μg.g-1) after 144 h at 25°C and 130 rpm in yeast malt (YM) medium containing 45.95 g.L-1 glucose, 1 g.L-1 malt extract, 0.7 g.L-1 yeast extract, and 0.4 g.L-1 peptone, with an initial pH value of 6. This result showed the potential of this yeast as a viable source of biopigments. [ABSTRACT FROM AUTHOR]

Abstract: Streptococcus agalactiae is among the most relevant aetiologic agent of bovine clinical and subclinical mastitis, a major problem for the dairy industry. In Brazil, clonal diversity, capsular typing and multidrug resistance profiles of S. agalactiae related to human and bovine infections need further investigation. Presently, S. agalactiae isolates of bovine subclinical mastitis, from Brazilian Northeastern region, were submitted to capsular and pulsed‐field gel electrophoresis (PFGE)‐typing, antimicrobial susceptibility and assays of biofilm formation at different time incubation and pH levels. Sixteen bovine isolates were characterized by polymerase chain reaction assay as S. agalactiae capsular type II (CTII) and classified by PFGE in A1/A2 (n = 06), B1/B2 (n = 06), C (n = 03) and D (n = 01) patterns. Bovine S. agalactiae CTII strains were classified as 25% multidrug‐resistant (MDR) with susceptibility to penicillin, linezolid and vancomycin. Biofilm formation on abiotic surface was strain‐ and time‐dependent with significantly higher rates at pH 6·5. In conclusion, S. agalactiae capsular type II isolates recovered from bovine subclinical mastitis produced different pH‐dependent biofilm levels. Our findings suggest that biofilm production is modulated by environmental factors and provides S. agalactiae advantageous in colonizing mammary gland during mastitis development, including MDR strains. Significance and Impact of the Study: Streptococcus agalactiae is among the most relevant aetiologic agent of bovine clinical and subclinical mastitis, a major problem for the dairy industry. The disease may cause significant economic loss due to decreased production and milk quality and increased use of medicaments. Presently, data demonstrated that biofilm formation favours the establishment of infectious process in health mammary tissue by S. agalactiae and emphasizes that an acidic pH promotes adhesion by biofilm‐forming bacterial strains. S. agalactiae strains (25%) showed resistance to tetracycline, azithromycin, erythromycin and clindamycin, and consequently were classified as multidrug‐resistant strains. [ABSTRACT FROM AUTHOR]

This experiment evaluated the impacts of supplementing a yeast-derived product (Celmanax; Church & Dwight Co., Inc., Princeton, NJ, USA) on productive and health responses of beef steers, and was divided into a preconditioning (days 4 to 30) and feedlot receiving phase (days 31 to 69). In all, 84 Angus × Hereford steers were weaned on day 0 (BW=245±2 kg; age=186±2 days), and maintained in a single group from days 0 to 3. On day 4, steers were allocated according to weaning BW and age to a 21-pen drylot (4 steers/pen). Pens were randomly assigned to ( n =7 pens/treatment): (1) no Celmanax supplementation during the study, (2) Celmanax supplementation (14 g/steer daily; as-fed) from days 14 to 69 or (3) Celmanax supplementation (14 g/steer daily; as-fed) from days 31 to 69. Steers had free-choice access to grass-alfalfa hay, and were also offered a corn-based concentrate beginning on day 14. Celmanax was mixed daily with the concentrate. On day 30, steers were road-transported for 1500 km (24 h). On day 31, steers returned to their original pens for the 38-day feedlot receiving. Shrunk BW was recorded on days 4, 31 and 70. Feed intake was evaluated daily (days 14 to 69). Steers were observed daily (days 4 to 69) for bovine respiratory disease (BRD) signs. Blood samples were collected on days 14, 30, 31, 33, 35, 40, 45, 54 and 69, and analyzed for plasma cortisol, haptoglobin, IGF-I, and serum fatty acids. Preconditioning results were analyzed by comparing pens that received (CELM) or not (CONPC) Celmanax during the preconditioning phase. Feedlot receiving results were analyzed by comparing pens that received Celmanax from days 14 to 69 (CELPREC), days 31 to 69 (CELRECV) or no Celmanax supplementation (CON). During preconditioning, BRD incidence was less ( P =0.03) in CELM v. CONPC. During feedlot receiving, average daily gain (ADG) ( P =0.07) and feed efficiency ( P =0.08) tended to be greater in CELPREC and CELRECV v. CON, whereas dry matter intake was similar ( P ⩾0.29) among treatments. No other treatment effects were detected ( P ⩾0.20). Collectively, Celmanax supplementation reduced BRD incidence during the 30-day preconditioning. Moreover, supplementing Celmanax tended to improve ADG and feed efficiency during the 38-day feedlot receiving, independently of whether supplementation began during preconditioning or after feedlot entry. These results suggest that Celmanax supplementation benefits preconditioning health and feedlot receiving performance in beef cattle. [ABSTRACT FROM AUTHOR]

This experiment evaluated the impacts of estrus expression and intensity, estimated by physical activity during a timed-AI protocol, on reproductive performance of Bos indicus-influenced beef cows. A total of 290 lactating, primiparous, and multiparous nonpregnant Nelore × Angus cows received a 2 mg injection of estradiol benzoate and an intravaginal progesterone (P4) releasing device (CIDR) on d -11, a 12.5 mg injection of PGF2α on d -4, CIDR removal in addition to 0.6 mg injection of estradiol cypionate and 300 IU injection of eCG on d -2, and timed-AI on d 0. Cows were fitted with a pedometer behind their left shoulder on d -4. An estrus detection patch was attached to the tail-head of each cow on d -2. Pedometer results were recorded on d -2 and 0. Estrus expression was defined as removal of >50% of the rub-off coating from the patch on d 0. Net physical activity during estrus was calculated by subtracting total steps from d -4 to -2 (nonestrus basal activity) from total steps from d -2 to 0 (proestrus + estrus period) of each cow. Cows that did not express estrus were classified as NOESTR. Cows that expressed estrus were ranked by net physical activity; those above the median were classified as HIESTR and the remaining cows as LWESTR. Ovarian ultrasonography was performed on d 0 and 7. Blood was collected on d 0, 7, 20, and 30. Pregnancy status was verified by ultrasonography on d 30. Only data from cows responsive to the estrus synchronization protocol were utilized (NOESTR, n = 59; LWESTR, n = 100; HIESTR, n = 98). Diameter of dominant follicle on d 0, corpus luteum volume on d 7, and plasma P4 concentrations on d 7 were greater (P ≤ 0.05) in HIESTR vs. LWESTR and NOESTR and also greater (P ≤ 0.05) for LWESTR vs. NOESTR. Plasma P4 concentrations on d 0 were greater (P < 0.01) in NOESTR vs. HIESTR and LWESTR and similar (P = 0.93) between HIESTR and LWESTR. Whole blood mRNA expression of myxovirus resistance 2 on d 20 was greater (P ≤ 0.05) in HIESTR vs. LWESTR and NOESTR, and similar (P = 0.72) between LWESTR and NOESTR. Pregnancy rates were less (P ≤ 0.04) in NOESTR vs. HIESTR and LWESTR (52.4%, 68.9%, and 73.5%, SEM = 7.2), and similar (P = 0.57) between HIESTR and LWESTR. Hence, expression of estrus during a timed-AI protocol improved ovarian dynamics and pregnancy success, whereas estrus intensity modulated key biological markers associated with fertility but not pregnancy rates in B. indicus-influenced cows beef cows. [ABSTRACT FROM AUTHOR]

In all, 60 Angus×Hereford heifers were ranked by age and BW (210±2 days and 220±2 kg) on day 0, and assigned to: (a) one of three drylot pens (10×14 m pens; 10 heifers/pen) resulting in a stocking density of 14 m2/heifer (HIDENS; n=3), or (b) one of three pastures (25 ha pastures; 10 heifers/pasture), resulting in a stocking density of 25 000 m2/heifer (LOWDENS; n=3). Pastures were harvested for hay before the beginning of this experiment, and negligible forage was available for grazing to LOWDENS heifers during the experiment (days 0 to 182). All heifers received the same limited-fed diet, which averaged (dry matter basis) 4.0 kg/heifer daily of hay and 3.0 kg/heifer daily of a corn-based concentrate. Heifer shrunk BW was recorded after 16 h of feed and water withdrawal on days −3 and 183 for BW gain calculation. On day 0, heifers were fitted with a pedometer behind their right shoulder. Each week, pedometer results were recorded and blood samples were collected for puberty evaluation via plasma progesterone. Plasma samples collected on days 0, 28, 56, 84, 112, 140, 161 and 182 were also analyzed for cortisol concentrations. On days 0, 49, 98, 147 and 182, hair samples were collected from the tail switch for analysis of hair cortisol concentrations. On days 28, 102 and 175, blood samples were collected for whole blood RNA isolation and analysis of heat shock protein (HSP) 70 and HSP72 mRNA expression. Heifers from LOWDENS had more (P<0.01) steps/week compared with HIDENS. No treatment effects were detected (P=0.82) for heifer BW gain. Plasma cortisol concentrations were greater (P⩽0.05) in LOWDENS compared with HIDENS heifers on days 84, 140, 161 and 182 (treatment×day interaction; P<0.01). Hair cortisol concentrations were greater (P<0.01) in HIDENS compared with LOWDENS heifers beginning on day 98 (treatment×day interaction; P<0.01). Heifers from LOWDENS had greater (P=0.04) mean mRNA expression of HSP72, and tended (P=0.09) to have greater mean mRNA expression of HSP70 compared with HIDENS. Heifers from HIDENS experienced delayed puberty attainment and had less (P<0.01) proportion of pubertal heifers on day 182 compared with LOWDENS (treatment×day interaction; P<0.01). In summary, HIDENS altered heifer stress-related and physiological responses, and delayed puberty attainment compared with LOWDENS. [ABSTRACT FROM PUBLISHER]

The objective of this study was to evaluate the effects of the hormones prolactin (PRL) and hydrocortisone (HC) on bovine mammary alveolar (MAC-T) cells mitogen-activated protein kinase (MAPK) inflammatory signaling and inflammatory gene expression. MAC-T cells were cultured in the presence (+PRL +HC; Dulbecco's modified Eagle's medium [DMEM] 10% fetal bovine serum, 10 μg/mL of insulin, 100 IU/mL penicillin, 100 μg/mL streptomycin, 1 μg/mL ovine PRL, 0.5 μg/mL HC, and 10 mM sodium acetate) or the absence (-PRL -HC; DMEM 10% fetal bovine serum, 10 μg/mL insulin, 100 IU/mL penicillin, and 100 μg/mL streptomycin) of PRL and HC, and MAPK (extracellular signal-regulated kinase [ERK], c-Jun N-terminal kinase [JNK], and p38) phosphorylation and inflammatory gene expression were examined in response to tumor necrosis factor α (TNFα). Statistical analysis was assessed using 1-way ANOVA, and Tukey's post hoc analysis was used to assess statistical significance when P ≤ 0.05. MAC-T cells cultured in +PRL +HC and -PRL -HC were costimulated with increasing concentrations of TNFα (0, 10, 30, 100, 300, and 1,000 pM). Cell lysates were harvested 15 min after TNFα stimulation and assessed for MAPK phosphorylation using immunoblotting. c-Jun N-terminal kinase and p38 phosphorylation increased in a dose-dependent manner and was greater in cells cultured in -PRL -HC. MAC-T cells cultured in +PRL +HC and -PRL -HC were next stimulated with TNFα (300 pM), and lysates were harvested over time (0, 15, 30, 60, 120, and 180 min) after TNFα stimulation. c-Jun N-terminal kinase and p38 phosphorylation was transiently increased in MAC-T cells stimulated with TNFα; however, JNK and p38 signaling was greater in MAC-T cells cultured in -PRL -HC. We next examined inflammatory gene expression in MAC-T cells cultured in +PRL +HC and -PRL -HC. Cells were co-stimulated with (300 pM) or without TNFα. Ribonucleic acid was isolated 1 h after TNFα stimulation, and a PCR array was performed to examine the expression of 83 inflammatory genes. Gene expression was increased in MAC-T cells in response to TNFα. Consistent with enhanced MAPK signaling, inflammatory gene expression was increased in MAC-T cells cultured in -PRL -HC. Real-time quantitative PCR of 6 target genes was used to validate the PCR array findings. Collectively, our data demonstrate that -PRL -HC MAC-T cells are more responsive to TNFα stimuli. These findings suggest that cell culture conditions (e.g., treatment with hormones) greatly impact cellular response and should be considered prior to experimental design and hypothesis testing. [ABSTRACT FROM AUTHOR]

This experiment evaluated production and health parameters among cattle offered concentrates containing inorganic or organic complexed sources of supplemental Cu, Co, Mn and Zn during a 45-day preconditioning period. In total, 90 Angus×Hereford calves were weaned at 7 months (day −1), sorted by sex, weaning BW and age (261±2 kg; 224±2 days), and allocated to 18 drylot pens (one heifer and four steers per pen) on day 0; thus, all pens had equivalent initial BW and age. Pens were randomly assigned to receive a corn-based preconditioning concentrate containing: (1) Cu, Co, Mn and Zn sulfate sources (INR), (2) Cu, Mn, Co and Zn complexed organic source (AAC) or (3) no Cu, Co, Mn and Zn supplementation (CON). From day 0 to 45, cattle received concentrate treatments (2.7 kg/animal daily, as-fed basis) and had free-choice access to orchardgrass (Dactylis glomerata L.), long-stem hay and water. The INR and AAC treatments were formulated to provide the same daily amount of Co, Cu, Mn and Zn at a 50-, 16-, 8- and ninefold increase, respectively, compared with the CON treatment. On day 46, cattle were transported to a commercial feedlot, maintained as a single pen, and offered a free-choice receiving diet until day 103. Calf full BW was recorded on days −1 and 0, 45 and 46, and 102 and 103 for average daily gain (ADG) calculation. Liver biopsy was performed on days 0 (used as covariate), 22 and 45. Cattle were vaccinated against respiratory pathogens on days 15, 29 and 46. Blood samples were collected on days 15, 29, 45, 47, 49, 53 and 60. During preconditioning, mean liver concentrations of Co, Zn and Cu were greater (P⩽0.03) in AAC and INR compared with CON. No treatment effects were detected (P⩾0.17) for preconditioning feed intake, ADG or feed efficiency. No treatment effects were detected (P⩾0.48) for plasma concentrations of antibodies against Mannheimia haemolytica, bovine viral diarrhea types 1 and 2 viruses. Plasma haptoglobin concentrations were similar among treatments (P=0.98). Mean plasma cortisol concentration was greater (P⩽0.04) in CON compared with INR and AAC. No treatment effects were detected (P⩾0.37) for cattle ADG during feedlot receiving. Hence, INR and AAC increased liver concentrations of Co, Zn and Cu through preconditioning, but did not impact cattle performance and immunity responses during preconditioning and feedlot receiving. [ABSTRACT FROM PUBLISHER]

One hundred eight Angus × Hereford steers, originating from 7 cow-calf were obtained from an auction yard on d -2 and transported by road (800 km; 12 h) to an experimental feedlot facility. Upon arrival on d -1, shrunk BW was recorded and steers were grouped with free-choice access to grass hay, mineral supplement, and water. On d 0, steers were ranked by source and shrunk BW and assigned to 1 of 18 pens (6 steers/pen). Pens were allocated to 1) no immunomodulatory ingredient supplementation during feedlot receiving (CON), 2) supplementation with OmniGen-AF (OMN; 22 g/steer daily, as-fed basis; Phibro Animal Health Corp., Teaneck, NJ) from d 0 to 30, or 3) 2 oral capsules of Stocker Immune Primer on d 0 + 15 g/steer daily (as-fed basis) of Stocker Preconditioned Premix (Ramaekers Nutrition, Santa Cruz, CA) from d 7 to 30 (IPF). From d 0 to 80, steers had free-choice access to grass hay and water and received a corn-based concentrate. Feed DMI was recorded from each pen, and steers were assessed for bovine respiratory disease (BRD) signs daily. Steers were vaccinated against BRD pathogens on d 0 and 21. Final shrunk BW was recorded on d 81, and blood samples were collected on d 0, 3, 7, 10, 14, 21, 31, 42, 56, and 73. Steer ADG and final BW were greater (P = 0.05) in CON steers than in OMN and IPF steers (1.23, 0.76, and 1.06 kg/d [SEM 0.06], respectively, and 320, 282, and 307 kg [SEM 4], respectively) and (P < 0.01) in IPF steers than in OMN steers. No treatment effects were detected (P = 0.76) for BRD incidence (66 ± 4%) and DMI, whereas G:F was greater (P < 0.01) in OMN steers than in CON steers. Mean plasma cortisol concentration was greater (P = 0.01) in CON steers than in OMN and IPF steers. Plasma haptoglobin concentrations tended (P = 0.10) to be greater in CON steers than in IPF steers on d 3, were greater (P = 0.04) in IPF steers than in CON steers on d 7, and tended (P = 0.10) to be less in OMN steers than in IPF and CON steers on d 21. Blood mRNA expression of interleukin 8 was greater (P = 0.05) in OMN and IPF steers than in CON steers on d 3 and in OMN steers than in CON and IPF steers on d 14. Blood mRNA expression of tumor necrosis-a was greater (P = 0.05) in OMN and IPF steers than in CON steers on d 10. Plasma IGF-I concentrations, serum antibody titers to BRD pathogens, and blood mRNA expression of chemokine ligand 5, cyclooxygenase 2, interleukin 8 receptor, and L-selectin did not differ (P = 0.21) among treatments. Collectively, the immunomodulatory feed ingredients evaluated herein impacted adrenocortical and innate immune responses but failed to mitigate BRD incidence and improve performance of receiving cattle. [ABSTRACT FROM AUTHOR]

Background: Resistant hypertension is a specific condition that affects approximately 10% of subjects with hypertension, and is characterized by persistently high blood pressure levels even using therapy of three or more antihypertensive agents or with blood pressure control using therapy with four or more antihypertensive agents. Changes in lifestyle, such as physical exercise, are indicated for controlling blood pressure. However, investigating studies about this therapy in individuals with resistant hypertension are few.Methods/design: This is a randomized controlled clinical trial. Forty-eight patients with resistant hypertension will be submitted to perform four short-term interventions: aerobic exercise sessions (mild-, moderate- and high-intensity) and control session, in random order and on separate days. After the short-term sessions, the patients will be randomly allocated into four groups for 8 weeks of follow-up: mild-, moderate- and high-intensity aerobic exercise, and a control group. The primary outcome is the occurrence of blood pressure reduction (office and ambulatory analysis, and acute and chronic effects). Secondary outcomes are autonomic and hemodynamic mechanisms: cardiac and vasomotor autonomic modulation, spontaneous baroreflex sensitivity, forearm blood flow and vascular resistance.Discussion: The importance of exercise for hypertension has been known for decades, but little is known about the effects on patients with resistant hypertension. This study will help to understand whether different aerobic exercise intensities can induce different responses, as well as by what mechanisms adjustments in blood pressure levels may occur.Trial Registration: ClinicalTrials.gov, ID: NCT02670681 . Registered on 28 January 2016 (first version); Brazilian Registry Platform Clinical Trials: protocol RBR-5q24zh . Registered on 24 June 2015. [ABSTRACT FROM AUTHOR]

Fish attempting to move upstream through hydroelectric dams can be trapped and killed in turbines. Understanding fish movement patterns can provide useful insights for how to manage dam operations to minimize fish kill in turbines. We evaluated the movements of two migratory fish (Curimba-Prochilodus argenteus and Mandi-Pimelodus maculatus) using acoustic telemetry in the tailrace of Três Marias Dam (São Francisco River, Brazil) from 31 October 2011 to 16 February 2012. The majority of tagged fish left the tailrace in less than one week; however, some individuals returned, performing several visits to the tailrace. Mandi remained longer in the tailrace than Curimba. The number of visits was influenced by diel period, turbine and spillway discharge. Although the diel period was the only important contributor to the visits performed by Curimba, the movements of Mandi were significantly influenced by three factors. We found that whereas Curimba was predominantly diurnal, Mandi showed nocturnal habits. Additionally, visits of Mandi were significantly greater during higher turbine and spillway discharge. We discuss the implications of these results for understanding fish movements in the Três Marias Dam tailrace and their potential implications for adapting hydroelectric operations to minimize fish kills. [ABSTRACT FROM AUTHOR]

Cheatgrass (CG; Bromus tectorum), an introduced winter annual grass, is an aggressive invader of the sagebrush community in the Western United States. Because of its greater flammability, mature CG constitutes a fire hazard leading to repeated wildfires. One fuel-reduction strategy is livestock grazing. The objective of this study was to evaluate the effects of urea, molasses, or a combination of urea and molasses supplementation of a CG-based diet on digestibility, microbial fermentation, bacterial protein synthesis, and nutrient flow using a dual-flow continuous culture system. Eight fermenters were used in a replicate 4 x 4 Latin square design with four 10-d experimental periods. Experimental treatments (DM basis) were 1) forage only (CON), 2) CG plus urea alone (URE; 1.36% urea), 3) CG plus molasses alone (MOL; 15.9% molasses), and 4) CG plus urea and molasses combined (URE+MOL; 1.28% urea plus 19.3% molasses). Each fermenter was fed 72 g/d of DM, and data were analyzed using the GLIMMIX procedure of SAS (SAS Inst. Inc., Cary, NC). The true digestibilities of NDF and ADF were not affected by diets (P > 0.05). Molasses-containing diets had greater true digestibility of OM (P = 0.02). However, true digestibility of CP was increased when molasses was fed alone (P < 0.01). Molasses-containing diets had lower pH (P < 0.01) and greater VFA concentrations (P < 0.01) compared to those of the other diets. The URE+MOL diet resulted in a greater VFA concentration (P < 0.01). Propionate concentration increased (P < 0.01), whereas acetate concentration decreased (P < 0.01) when molasses alone or in combination with urea was added to the diets. Supplying molasses alone resulted in greater (P = 0.03) total branched-chain VFA compared to the other diets. The concentration of NH3-N and total N flow increased (P < 0.01) in response to urea supplementation and was greater (P < 0.01) when urea alone was supplemented in the diet. On the other hand, molasses- supplemented diets yielded more non-ammonia N (P < 0.01) and bacterial N (P = 0.04). Supplementation had no effect (P = 0.83) on bacterial efficiency. Results from this study indicate that the addition of urea and molasses in a CG-based diet could improve nutrient supply to animals, notably VFA supply and microbial N supply; however, in the levels tested in this study, it did not improve CG utilization as assessed by NDF digestion. [ABSTRACT FROM AUTHOR]

This experiment evaluated the effects of temperament on physiological, productive, and reproductive responses in Bos indicus beef cows. A total of 953 lactating, multiparous, non-pregnant Nelore cows (age = 99 ± 2 mo; days post-partum = 51.4 ± 0.3 d; BCS = 5.34 ± 0.04; BW = 430 ± 2 kg) were allocated into 8 groups of approximately 120 cows each. Groups were assigned to an estrus synchronization + timed- AI protocol at the beginning of the breeding season. Concurrently with AI, blood samples were collected, hair samples were clipped from the tail switch, and cow temperament was evaluated via chute score and exit velocity. Individual exit score was calculated within each group by dividing exit velocity into quintiles and assigning cows with a score from 1 to 5 (1 = slowest; 5 = fastest cow). Temperament scores were calculated by averaging cow chute score and exit score, and used to define cow temperament ( ≤ 3 = adequate, n = 726; ADQ; > 3 = excitable, n = 227; EXC). Cows not pregnant to AI were assigned to a second timed-AI protocol (n = 184 ADQ and 72 EXC) or exposed (n = 269 ADQ and 90 EXC) to bulls for 60 d. Pregnancy status was verified 30 d after each AI and 45 d after the breeding season via transrectal ultrasound. Cow age, BW, BCS, and d post-partum at the beginning of the breeding season were similar (P ≥ 0.27) between ADQ and EXC cows. At first timed-AI, EXC had greater (P < 0.01) serum cortisol but similar (P ≥ 0.87) serum haptoglobin and hair cortisol concentrations compared with ADQ cows (49.1 vs. 39.1 ng/mL of serum cortisol, SEM = 1.0). Pregnancy rate to first timed-AI tended (P = 0.09) to be less in EXC vs. ADQ cows (41.0 vs. 47.3%; SEM = 3.6), whereas no treatment differences were detected (P ≥ 0.23) for subsequent pregnancy outcomes. Calving rate was less (P = 0.04) in EXC vs. ADQ cows (68.3 vs. 74.8%; SEM = 2.2), which can be attributed to the greater (P = 0.05) pregnancy loss detected in EXC cows (9.9 vs. 5.9%; SEM = 1.4). Weaning rate tended (P = 0.09) to be less, whereas calf weaning BW and age were less (P ≤ 0.05) in EXC vs. ADQ cows (63.9 vs. 69.4%, SEM = 2.4; 209 vs. 212 d, SEM = 1; 204 vs. 210 kg, SEM = 2). Hence, kg of calf weaned/cow exposed to breeding was reduced (P = 0.04) in EXC vs. ADQ cows (130 vs. 146 kg, SEM = 5). In summary, B. indicus cows with excitable temperament had reduced reproductive performance and overall productivity compared to cohorts with adequate temperament when exposed to timed-AI + natural breeding. [ABSTRACT FROM AUTHOR]

This paper presents an electromagnetic characterization of aircraft composite materials, as well as numerical and experimental analyses of its effects on the antenna performance. Two uncalibrated S-parameters characterization methods have been applied for retrieving the complex electrical permittivity in the L- and C-band, namely: Air-region method and Sample-shifted method. Dielectric constants of 4.6 and 1.84 and loss tangent of 2.0x10-2 and 6.1x10-2 have been obtained for fiberglass and honeycomb composite materials, respectively. A 3.0-meters prototype of an Embraer light jet aircraft dorsal fin was fabricated and used in the experiments in a semi-anechoic chamber in order to evaluate the impact of installing aeronautical VHF and L-band antennas on a fuselage made of composite materials. [ABSTRACT FROM AUTHOR]

This paper presents an optically controlled reconfigurable antenna for millimetre-wave frequency range. Silicon switches are used to control the optical reconfiguration, modifying the frequency response and radiation pattern of the antenna design. Therefore, the system can switch between the lightly licensed 28 GHz and 38 GHz frequency bands, useful for future mobile 5G broadband cellular communication networks. Experimental results with the reconfigurable antenna on 16-QAM and 32-QAM wireless transmission supported by photonic downconversion are successfully reported under 78 dB link budget requirement. [ABSTRACT FROM AUTHOR]

The objective of this experiment was to compare hormonal, uterine, and conceptus factors associated with pregnancy establishment in Bos indicus beef cows supplemented or not with Ca salts of soybean oil (CSSO) for 21 d beginning after timed AI. One hundred lactating multiparous Nelore cows were allocated to 20 groups of 5 cows/group and timed inseminated on d 0 of the experiment. After AI, groups were randomly assigned to receive (as-fed basis) 100 g of protein–mineral mix + 100 g of ground corn per cow per day, in addition to 1) 100 g/cow daily of CSSO (n = 10) or 2) 100 g/cow daily of kaolin (CON; rumen-inert indigestible substance; n = 10). Groups were maintained in 4 Panicum maximum pastures (5 groups from the same treatment within each pasture) with ad libitum access to forage. Groups were segregated daily and individually offered treatments from d 0 to 21. Blood samples were collected and transrectal ultrasonography was performed to verify ovulation and corpus luteum (CL) volume immediately before AI (d 0) and on d 7 and 15. After ultrasonography on d 15, 60 cows (30 cows/treatment and 3 cows/group) diagnosed without the presence of a CL on d 0 but with a CL greater than 0.38 cm3 in volume on d 7 and 15 were assigned to conceptus collection via transcervical flushing with PBS followed by endometrial biopsy in the uterine horn ipsilateral to the CL. Additional blood samples were collected for whole-blood RNA extraction (d 20), and pregnancy status was verified by transrectal ultrasonography (d 30) in cows not assigned to conceptus collection. Cows receiving CSSO had greater (P ≤ 0.04) mean plasma linoleic acid concentration, plasma linoleic:linolenic acid ratio, plasma progesterone (P4) concentration, and CL volume during the experiment compared with CON cows. Moreover, CSSO supplementation increased (P ≤ 0.04) length and mRNA expression of prostaglandin E synthase and interferon-tau by the conceptus as well as blood mRNA expression of interferon-stimulated genes on d 20 in gestating cows. No treatment differences were detected (P ≥ 0.30) for endometrial mRNA expression of prostaglandin E synthase and cyclooxygenase-2. In summary, post-AI CSSO supplementation to B. indicus beef cows increased plasma concentration of linoleic acid and enhanced pregnancy establishment factors, which included CL development and plasma P4 concentration, conceptus growth, and mRNA expression of interferon-tau as well as blood mRNA expression of interferon-stimulated genes. [ABSTRACT FROM AUTHOR]

Ninety Angus × Hereford calves were ranked by sex, BW, and age and assigned to 1 of 3 vaccination schemes against the bovine respiratory disease complex: 1) vaccination at weaning (d 0) and a booster at feedlot entry (d 30; CON; n = 30), 2) vaccination 15 d before weaning (d -15) and a booster 15 d before feedlot entry (d 15; EARLY; n = 30), and 3) vaccination 15 d after weaning (d 15) and a booster 15 d after feedlot entry (d 45; DELAYED; n = 30). From d -15 to 7, calves were maintained as a single group on pasture. On d 8, calves were placed into 1 of 18 drylot pens (6 pens/treatment; 5 calves/pen) and fed alfalfa-triticale hay. On d 29, calves were transported 1,440 km in a livestock trailer and unloaded on d 30 at the same feed yard with the same pen arrangement used prior to transport. From d 30 to 75, calves were fed a receiving diet based on alfalfa–triticale hay + corn-based concentrate. Calf BW was recorded on 2 consecutive days (d -15, -14, 0, 1, 28, 29, 75, and 76). Blood samples were collected on d -15, 0, 15, 30, 45, 60, and 75. The EARLY calves had less (P ≤ 0.09) ADG before weaning (d -15 to -1); however, they had greater (P ≤ 0.01) ADG during feedlot receiving (d 30 to 75) compared with calves with the other treatments. During preconditioning (d 0 to 29), CON calves had greater (P ≤ 0.04) DMI compared with EARLY and DELAYED calves. During feedlot receiving, no treatment differences were detected (P ≥ 0.17) for hay or concentrate DMI, G:F, and morbidity and mortality rates. There were no treatment effects on calf BW at weaning and at the end of the preconditioning or receiving periods (P ≥ 0.65). Plasma concentrations of antibodies against Mannheimia haemolytica were greater (P ≤ 0.05) in EARLY calves than in CON and DELAYED calves on d 0, greater (P ≤ 0.04) for CON calves than for EARLY and DELAYED calves on d 15, greater (P ≤ 0.02) in DELAYED and EARLY calves than in CON calves on d 30, and greater (P = 0.03) in EARLY calves than in CON calves on d 75. Plasma concentrations of antibodies against bovine viral diarrhea viruses were greater (P ≤ 0.04) in EARLY calves than in CON and DELAYED calves on d 15 and greater for EARLY and CON calves than for DELAYED calves on d 30 and 45. Collectively, EARLY calves had greater plasma concentrations of antibodies against the evaluated pathogens at feedlot entry and increased ADG during receiving compared with their CON and DELAYED cohorts. Hence, anticipating initial and booster vaccinations against respiratory pathogens to provide both doses prior to feedlot entry appears to be a valid strategy to enhance cattle health and performance during feedlot receiving. [ABSTRACT FROM AUTHOR]

The jaguarundi Puma yagouaroundi is a small Neotropical cat that presents two main coloration phenotypes (grey/dark vs. reddish). Although these coat colour variants have been known for decades, and historically speculated to be associated with different habitats, their exact geographical distribution has never been mapped. Moreover, their association to different habitats has so far not been tested statistically, so that their ecological relevance with respect to varying environmental features remains unknown. Based on 566 location records encompassing the entire historical range of the species obtained from camera-traps, captures and skins held in scientific collections, we produced suitability models for both jaguarundi phenotypes using maximum entropy algorithms of niche modelling. The frequency of grey/dark jaguarundis is c. 80%, whereas reddish animals represent c. 20% of our overall sample set. However, there were marked differences in these frequencies across regions. Although the spatial distribution of grey/dark animals did not depart substantially from random expectations (as it encompassed the whole species range), the occurrence of the ancestral reddish form was strongly and significantly non-random. In spite of their broad distribution across multiple habitats, grey/dark animals were significantly associated with moist and dense forests, whereas reddish forms were associated with dry and open areas such as deserts and xeric landscapes. Furthermore, there were clear spatial differences in the suitability models generated for these coat colour phenotypes. We also employed the distribution models to investigate whether particular environmental predictors could explain these different distributions. Predictors related to moisture were especially influential on the differences between the grey/dark and reddish models, and demonstrate an effect of natural selection on coloration traits, suggesting that a complex interplay of different ecological processes regulates this system over evolutionary time. [ABSTRACT FROM AUTHOR]

This work is regarding the development of a novel antenna called optically controlled reconfigurable filtenna, which is based on the integration of a broadband printed antenna with a bandpass reconfigurable RF filter. The filter is designed by applying defected microstrip structure (DMS) technique and positioned in printed antenna feeding line in order to keep the same size of the original antenna. The filtenna bandwidth is optically reconfigurable by using two photoconductive silicon switches excited by CW laser at 808 nm. Numerical results rely on independent and switchable operational modes through the 2.4 and 5.1 GHz ISM bands, whereas measurements demonstrate two reconfigurable modes based on single-band/dual-band operation over the same frequency bands. The proposed device is validated by theoretical, numerical, and experimental results. [ABSTRACT FROM AUTHOR]

Flaxseed (FS) and chia seed (CS) are oilseeds rich in omega-3 fatty acids, which may change meat and milk composition when added to ruminants' diets and may have health benefits for humans. Literature on the effects of CS supplementation on ruminal metabolism is nonexistent. A dual-flow continuous culture fermenter system consisting of 6 fermenters was used to assess the effect of FS and CS supplementation in an alfalfa hay-based diet on ruminal fermentation, nutrient digestibility, microbial protein synthesis, and longchain fatty acid flow. Diets were randomly assigned to fermenters in a replicated 3 × 3 Latin square design, with 3 consecutive periods of 10 d each, consisting of 7 d for diet adaptation and 3 d for sample collection. Each fermenter was fed a total of 72 g of DM/d divided in 6 equal portions. Treatments were 1) alfalfa hay + calcium soaps of palm oil fatty acid (MEG; 69.3 g DM/d of alfalfa hay plus 2.7 g DM/d of calcium soaps of palm oil fatty acid), 2) alfalfa hay + FS (FLAX; 68.4 g DM/d of alfalfa hay plus 3.6 g DM/d of ground FS), and 3) alfalfa hay + CS (CHIA; 68.04 g DM/d of alfalfa hay plus 3.96 g DM/d of ground CS). Dietary treatments had similar amounts of total fat, and fat supplements were ground to 2-mm diameter. Effluents from the last 3 d of incubation were composited for analyses. Data were analyzed using the MIXED procedure of SAS. Ruminal apparent and true nutrient digestibility of all nutrients did not differ (P > 0.05) among treatments. Compared with MEG, FLAX and CHIA increased the flows of C18:3 n-3, C20:4 n-6, and total PUFA (P < 0.01). Both CHIA and FLAX treatments had greater ruminal concentrations of C18:0, indicating that both CS and FS fatty acids were extensively biohydrogenated in the rumen. The NH3-N concentration, microbial N flow, and efficiency of microbial protein synthesis were not affected (P > 0.05) by treatments. Lastly, there were no differences (P > 0.05) among diets for total VFA concentration and molar proportions of individual VFA. Results from this study indicate that FS and CS supplementation did not impair ruminal fermentation, digestibility, microbial efficiency, and ruminal N metabolism. Overall, CS appears to be as effective as FS as a fat source when added to ruminants' diets using a dual-flow continuous culture system. [ABSTRACT FROM AUTHOR]

This study was aimed to evaluate the behaviour of eighteen clones of Hevea brasiliensis (rubber) against South American leaf blight and to study progress of the disease. The experiment was conducted in Cachoeiro de Itapemirim- ES, where 18 clones were evaluated. The experimental design was a randomized block with four replicates; each experimental unit consisted of three plants. Evaluations were performed at 15-day intervals on 30 leaflets per tree. Disease incidence was quantified and infection classified according to the stages of development and type of damage. Leaf blight occurred during the entire experimental period; however, disease intensity varied with the resistance level of the clones and the time of year. Clones FX 3864, RRIM 725, RRIM 711, IAC 300 and IAN 873 exhibited the highest resistance to leaf blight. [ABSTRACT FROM AUTHOR]

Copyright of Revista Eletrônica de Materiais e Processos is the property of Revista Eletronica de Materiaia e Processos and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Plastics have been used in short-life products, which have presented harmful consequences for the nature, due to the low degradation rate reached by the most common polyolefins, such as the polypropylene. By this way, the incorporation of pro-oxidants has been shown nice results to the bio-assimilation of the common polymers. The aim of this study is to evaluate the mechanical and thermal properties of pure iPP, plasticized starch (TPS) with biodiesel glycerol (TPS) or commercial glycerol (TPS), and their blends (iPP/TPS). TPS was plasticized in proportions of 80/20 (wt starch/wt glycerin). Blends of iPP/TPS were obtained by extrusion in the following composition rates: 95/5, 90/10, 80/20, and 70/30 of modified PP/TPS. Mechanical properties, calorimetric analysis, and thermogravimetric data were obtained, and biodegradation under simulated soil was performed. It can be verified that there were no meaningful variation induced by the incorporation of TPS on the melting temperature on the blends, when compared to pure iPP. The addition of TPS caused an increasing on the crystallinity of iPP, mainly for the compositions 90/10 and 80/20 of iPP/TPS, probably due a morphological alteration such as crosslinking, which may have modified the molecular arrangement of the iPP macromolecules by the presence of glycerol, which was also indicated by mechanical evaluations. [ABSTRACT FROM AUTHOR]

Copyright of Saúde Coletiva is the property of MPM Comunicacao and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)