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To modify its characteristics, expand its applicability, and, in some cases, its processability, new blends using ultra-high-molecular-weight polyethylene (UHMWPE) have been developed. In this study, three different formulations of linear low-density polyethylene (LLDPE) and UHMWPE blends were prepared with 15, 30, and 45% (% w / w ) UHMWPE in the LLDPE matrix. All mixtures were prepared by hot pressing and were immersed in water for one hour afterwards at a controlled temperature of 90 °C to relieve the internal stresses that developed during the forming process. The thermal characterization showed that the blends showed endothermic peaks with different melting temperatures, which may be the result of co-crystallization without mixing between the polymers during the forming process. The mechanical characteristics presented are typical of a ductile material, but with the increase in the percentage of UHMWPE, there was a decrease in the ductility of the blends, as the elongation at rupture of the blends was higher than that of the pure components. The morphologies observed by SEM indicate that there were two phases in the blends. This is the result of the system's immiscibility due to the mode of preparation of the blends, wherein the two polymers may not have mixed intimately, confirming the results found with the thermal analyses.

The ergogenic effects of photobiomodulation therapy combined with a static magnetic field (PBMT-sMF) on exercises with characteristics similar to those of CrossFit® are unknown. This study was aimed at investigating the effects of PBMT-sMF applied at different times on recovery and physical performance in CrossFit® athletes by analyzing functional aspects, muscle damage, inflammatory processes, and oxidative stress. This was a prospectively registered, triple-blinded, placebo-controlled, crossover trial. CrossFit® athletes were recruited and assigned to receive one of the four possible interventions. Each intervention included protocols before and after the exercise (referred to as the workout of the day (WOD)). The four possibilities of intervention were as follows: placebo before and after WOD (placebo), PBMT-sMF before and placebo after WOD (PBMT-sMF before), placebo before and PBMT-sMF after WOD (PBMT-sMF after), and PBMT-sMF before and after WOD (PBMT-sMF before and after). The order of possibilities for the interventions was randomized. The primary outcome was the functional test performance. The secondary outcomes were the subjective perception of exertion, muscle damage, inflammation, and oxidative stress. The outcomes were measured before the WOD; immediately after the intervention; and 1, 24, and 48 hours after the WOD. Statistical analysis was performed using repeated measures ANOVA followed by the Bonferroni post hoc test to examine the differences between the interventions at each time point. Twelve participants were randomized and analyzed for each sequence. PBMT-sMF enhanced the performance on functional tests (calculated as a percentage of change) when applied before or after WOD in the assessment performed immediately post-WOD and at 24 and 48 hours later ( p < 0.05) compared to placebo and PBMT-sMF before and after WOD. In terms of the secondary outcomes, PBMT-sMF applied before or after WOD significantly decreased the creatine kinase, catalase, and superoxide dismutase activities and interleukin-6, thiobarbituric acid, and carbonylated protein levels (all p < 0.05) compared to the other possibilities of intervention. In addition, PBMT-sMF applied before and after WOD decreased creatine kinase activity at 24 hours and IL-6 levels at 24 and 48 hours compared to placebo ( p < 0.05). None of the participants reported any adverse events. PBMT-sMF enhanced the performance of functional tests, decreased the levels of biochemical markers of muscle damage and inflammation, decreased oxidative stress, and increased antioxidant activity in CrossFit® athletes when applied before or after WOD., Competing Interests: Professor Ernesto Cesar Pinto Leal-Junior received research support from Multi Radiance Medical (Solon, OH, USA), a laser device manufacturer. Shaiane Silva Tomazoni has a personal relationship with Ernesto Cesar Pinto Leal-Junior. The remaining authors declare that they have no support from any organization for the submitted work, no financial relationships with any organization with an interest in the submitted work within the last three years, and no other relationships or activities that could appear to have influenced the submitted work., (Copyright © 2022 Henrique Dantas Pinto et al.)

Peroxide has been considered a chemical agent that can be used to tune the properties of polymeric materials. This research evaluated the influence of different concentrations of dialkyl peroxides on the mechanical, thermal, and morphological properties of linear low-density polyethylene (LLDPE) and ultra-high molecular weight polyethylene (UHMWPE). The neat polymer, as well as those with the addition of 1% and 2% by mass of dialkyl peroxides, were subjected to compression molding and immersion in water for 1 h, under controlled temperatures of 90 °C. The values of the gel content found in the samples indicated that the addition of peroxide to the LLDPE and to the UHMWPE promoted the formation of a reticulated network. The structure obtained by the crosslinking led to less reorganization of the chains during the crystallization process, resulting in the formation of imperfect crystals and, consequently, in the reduction in melting temperatures, crystallization and enthalpy. The mechanical properties were altered with the presence of the crosslinker. The polymers presented had predominant characteristics of a ductile material, with the occurrence of crazing with an increased peroxide content.

Epoxy systems are widely applied as adhesives in the aerospace industry. They have excellent adhesion properties, however, being thermosetting, epoxy systems show fracture brittleness characteristics. Polysulfide and polymercaptans are good options to increase the flexibility of the epoxy adhesive. Thermal analysis techniques are generally used to evaluate the curing degree of epoxy systems. In most cases, when infrared (IR) analysis is used, it is employed qualitatively. This paper presents the reaction study of a DGEBA epoxy prepolymer with diethylenetriamine (DETA) and linear and branched dodecyl mercaptans as flexibilizers. Conversion data and curing time were assessed qualitatively and quantitatively by Fourier Transform Infrared Spectroscopy (FT-IR) in the medium infrared region (MIR) and in the near infrared region, using near infrared reflectance accessory (NIRA). NIRA methodology showed satisfactory results, with errors between 3 and 7%, especially in samples with lower amine contents. Mechanical tests confirmed the flexibilization of the cured epoxy system by the addition of mercaptans, indicating a lower crosslinking degree in the matrix. Young's modulus (E) significantly decreased from 2017 MPa to 578 MPa with the addition of approximately 20 wt% of normal dodecyl mercaptan to the epoxy system.

Background: The direct application of photobiomodulation therapy (PBMT) using low-level laser therapy (LLLT) and light emitting diodes (LEDs) combined with a static magnetic field (sMF) (PBMT-sMF) to target tissues is shown to improve muscle performance and recovery. Studies have reported possible PBMT effects when a local distant to the target tissue is irradiated. Notably, the extent of these effects on musculoskeletal performance and the optimal site of irradiation remain unclear, although this information is clinically important since these aspects could directly affect the magnitude of the effect. Therefore, we investigated the effects of local and non-local PBMT-sMF irradiations on musculoskeletal performance and post-exercise recovery before an eccentric exercise protocol., Methods: This randomized, triple-blind (participants, therapists and assessors), placebo-controlled trial included 30 healthy male volunteers randomly assigned to the placebo, local, and non-local groups. Active or placebo PBMT-sMF was applied to 6 sites of the quadriceps muscle of both legs. An eccentric exercise protocol was used to induce fatigue. The primary outcome was peak torque assessed by maximal voluntary contraction (MVC). The secondary outcomes were delayed onset muscle soreness (DOMS) measured by visual analogue scale (VAS), muscle injury assessed by serum creatine kinase activity (CK), and blood lactate levels. Evaluations were performed before the eccentric exercise protocol (baseline), as well as immediately after and 1, 24, 48, and 72 h upon protocol completion., Results: Ten volunteers were randomized per group and analysed for all outcomes. Compared to the placebo and non-local groups, irradiation with PBMT-SMF led to statistically significant improvement ( p  < 0.05) with regard to all variables in the local group. The outcomes observed in the non-local group were similar to those in the placebo group with regard to all variables.The volunteers did not report any adverse effects., Conclusion: Our results support the current evidence that local irradiation of all exercised muscles promotes ergogenic effects. PBMT-sMF improved performance and reduced muscle fatigue only when applied locally to muscles involved in physical activity., Trial Registration: NCT03695458. Registered October 04th 2018., Competing Interests: Competing interestsProfessor Ernesto Cesar Pinto Leal-Junior receives research support from Multi Radiance Medical (Solon - OH, USA), a laser device manufacturer. The remaining authors declare that they have no conflict of interests., (© The Author(s) 2020.)

Objectives: The aim of this study was to evaluate the effects of 8 weeks of strength training (ST) combined with whole-body electrical stimulation (EMS) on morphofunctional adaptations in active individuals., Methods: Fifty-eight volunteers were randomly distributed into the following groups: an untrained control (UN) group (n=16), an ST group (n=21) or an ST combined with EMS (ST+EMS) group (n=21). Both intervention groups (the ST and ST+EMS groups) performed 3 exercises (biceps curl, back squats and high-pulley tricep extensions) twice a week for 8 weeks. The subjects performed 3 sets of 8 to 12 maximum repetitions (MRs) with a 90-second rest duration between sets. The ST+EMS group performed the resistance training exercises wearing a whole-body suit that provided electrical stimulation at frequencies between 80-85 Hz, with a continuously bipolar impulse duration and pulse breadth of 350 µs. The intensity for each muscle group was controlled by Borg's category ratio (CR)-10 scale; the intensity started at 5-6 and eventually reached 7-8. One-repetition maximum strength (1RM) and muscle thickness (MT) were measured before and after the training intervention. MT was evaluated in the biceps brachii (BB), triceps brachii (TB), and vastus lateralis (VL)., Results: No differences (p>0.05) were found between the ST and ST+EMS groups. Improvements (p<0.05) in the absolute values of the morphofunctional parameters after the training protocol were observed. Significant differences were found between both the intervention groups and the UN group (p<0.05). The ST+EMS group presented high percentage changes (p<0.05) in muscular strength for the 1RMsquat (43.2%, ES=1.64) and the MT of the BB (21.6%, ES=1.21) compared to the ST (20.5%, ES=1.43, 11.9%, ES=0.77) group., Conclusions: Our data suggest that the combination of ST+EMS may promote alterations in muscle strength and MT in healthy active subjects.

The solid waste management problems caused by the accumulation of plastics require measures to mitigate the environmental damage, and mechanical recycling of plastics is among the possible solutions. In this context, the present study aimed to evaluate the effects of mechanical recycling on the properties of a polypropylene/poly(butylene adipate co-terephthalate)-thermoplastic starch blend (PP/PBAT-Thermoplastic starch blend) when it was subjected to seven reprocessing cycles by a single-screw extruder. The observations by infrared spectroscopy indicated that the chemical structures of the blend and the polypropylene matrix did not present significant changes with the reprocessing cycles. The X-ray diffraction analyses showed that the PP crystals were most affected when reprocessed in their pure form. The observations by thermogravimetry and differential scanning calorimetry indicated that the thermal stability of the blend was higher than that of polypropylene during the extrusion cycles. The scanning electron microscopy images indicated a weak interfacial interaction between the components of the blend, and the mechanical properties showed that the reprocessing improved the elasticity modulus and yield stress, with a consequential decrease of the impact strength., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Ureaplasma diversum infection in bovine females may result in various reproductive problems, including granular vulvovaginitis, abortion, weak calves, salpingitis, and spontaneous abortion. The presence of U. diversum in a dairy bovine population from midwestern Brazil has not been established. The aim of this study was to determine whether U. diversum was present in dairy cattle from midwestern Brazil using polymerase chain reaction (PCR). Vulvovaginal mucus was analyzed from 203 cows located in six municipalities in the north region of Mato Grosso State, Brazil. A total of 25% of dairy cows with vulvovaginitis were positive for U. diversum. The factors evaluated were included in a multivariable logistic regression model with the presence of at least one positive cow in the herd serving as the dependent variable. Three variables were significantly associated with a U. diversum-positive PCR and were included in the final multivariable model: number of parities, vulvar lesions, and reproductive problems. For each new parity, the chance of U. diversum infection decreased 0.03-fold, indicating that cows with the highest number of parities were more protected. The presence of vulvar lesions was increased 17.6-fold in females positive for U. diversum, suggesting that this bacterium could be related to the red granular lesions in the vulvar mucosa, whereas reproductive problems were increased 7.6-fold. However, further investigations should be conducted to ascertain the effects of U. diversum in association with other mycoplasma species in the herds studied.

Context and Objective: Intraoperative nerve monitoring has emerged as a valuable tool to facilitate recurrent laryngeal nerve identification during thyroid surgery, thereby avoiding its injury. The aim was to evaluate vocal fold mobility in patients who underwent thyroidectomy with intraoperative nerve monitoring., Design and Setting: Cohort formed by a consecutive series of patients, at a tertiary cancer hospital., Methods: The subjects were patients who underwent thyroidectomy using intraoperative laryngeal nerve monitoring, between November 2003 and January 2006. Descriptive analysis of the results and comparison with a similar group of patients who did not undergo nerve monitoring were performed., Results: A total of 104 patients were studied. Total thyroidectomy was performed on 65 patients. Vocal fold immobility (total or partial) was detected in 12 patients (6.8% of the nerves at risk) at the first postoperative evaluation. Only six (3.4% of the nerves at risk) continued to present vocal fold immobility three months after surgery. Our previous series with 100 similar patients without intraoperative nerve monitoring revealed that 12 patients (7.5%) presented vocal fold immobility at the early examination, and just 5 (3.1%) maintained this immobility three months after surgery, without significant difference between the two series., Conclusion: In this series, the use of intraoperative nerve monitoring did not decrease the rate of vocal fold immobility.

Objective: An epidemiological investigation was conducted to determine risk factors for adverse reactions among patients in hospitals and the possibility of extrinsic or intrinsic contamination of intravenous solutions., Design: A retrospective cohort study was conducted to identify solutions associated with adverse reactions. Implicated lots were cultured for bacteria, and endotoxin concentrations were measured., Setting: Five hospitals in the state of Pernambuco, Brazil, were investigated from February through March 2002., Patients: Surgical inpatients or outpatients receiving intravenous solutions during the study period., Results: Of 355 surgical patients or outpatients treated at hospitals, 28 (8%) developed illness within a mean of 2.5 hours after exposure to intravenous solutions implicated in adverse reactions; 5 (17.9%) of the case patients died. Laboratory testing of bottles from the lots of Ringer's lactate solution implicated in deaths demonstrated a high mean endotoxin concentration of 88.3 endotoxin units (EU)/mL (range, 9.7-298.0 EU/mL), compared with the permitted limit in Brazil of <0.5 EU/mL. Testing of metronidazole implicated in adverse reactions at another hospital and produced by the same company that manufactured the lots Ringer's lactate solution also showed high endotoxin concentrations (mean level, 8.3 EU/mL [range, 5.0-58.3 EU/mL]). The outbreak was controlled after a national recall of the implicated brand of intravenous solutions., Conclusions: Case patient status was associated with use of Ringer's lactate solution and metronidazole from large bottles, both of which were produced by the same company. High endotoxin concentrations were demonstrated in unopened bottles of implicated products, which is consistent with intrinsic contamination. The high mortality rate may have been compounded by the fact that clinicians administered additional volumes of contaminated 0.9% isotonic sodium chloride solution in response to hypotension or bleeding to some surgical patients. No additional case patients were identified after a national recall of products, inspection, closure of the implicated company's manufacturing facility, and establishment of random quality-control testing of intravenous solutions.

A series of house-to-house surveys in Central Brazil revealed 32 cases of reduction deformities of the limbs (brachydactyly, synbrachydactyly, ectrodactyly, amely, adactyly, achiry, apody, etc.) among 58,761 births (0.54 per thousand, being 0.66 per thousand among Whites and 0.43 per thousand among Mulattoes and Negroes). No sibship was found with two or more equally affected singleton members. One case of concordance among twins is referred. There were no parity, inbreeding, race and sex effects. Both hands and both feet were also equally affected. Precocious mortality and twinning were significantly higher among affected individuals. The presence of cleft lip and palate in one of our index patients may also reflect an etiological relationship. Among the sibs, the total incidence of congenital malformations was similar to that generally accepted for general populations.