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This study aimed to evaluate the toxicity of Piper hispidinervum essential oil (PHEO) against 11 Brazilian populations of Sitophilus zeamais (Coleoptera: Curculionidae). The effects of sublethal doses of PHEO on the behavior (walking and flying), respiration, and population growth (ri) of the insect populations were investigated. PHEO toxicity was determined through concentration–mortality bioassays, with mortality curves established using increasing PHEO concentrations ranging from 140.00 to 1000.00 μL kg−1. Behavior was evaluated based on walking distance, walking time, walking speed, walking time proportion, flight height, and flight takeoff success. Respiration was measured via the respiratory rate, while population growth (ri) was assessed through the instantaneous growth rate. All 11 populations of S. zeamais were susceptible to PHEO, showing no signs of resistance. The populations exhibited varying behavioral and physiological responses to sublethal exposure to PHEO, indicating different mitigation strategies. The results confirm that PHEO possesses insecticidal potential for controlling S. zeamais populations. However, the observed behavioral and physiological responses should be considered when establishing control measures in pest management programs for stored products. [ABSTRACT FROM AUTHOR]

This paper investigates the application of modal analysis in the results of a proposed robust state estimation technique to determine the most critical buses of power distribution systems within the context of voltage stability assessment. In the proposed approach, the Weighted Least Squares (WLS) technique is used to estimate state variables based on micro-PMUs (Phasor Measurement Units) and SMs (smart meters) measurements. The estimated voltage magnitudes and angles are used to form a reduced Jacobian matrix which provides the sensitivities of reactive powers and voltage magnitudes at each load bus. Based on the calculation of eigenvalues and eigenvectors, participation factors are estimated for each load bus. In order to minimize the influence of gross errors, a bad data detection procedure is performed using Chi-squared test. The proposed identification procedure is based on the Median Absolute Deviation (MAD) of the normalized measurement residuals. The corrupted measurements are re-weighted in the proposed methodology to suppress its influence on the results yielding high accurate estimates. Simulations are carried out using a 33-bus test system. The impact of distributed generation units, aleatory errors and bad data is evaluated by different case studies to prove the efficiency of the proposed method. [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic is the biggest public health threat facing the world today. Multiple vaccines have been approved; however, the emergence of viral variants such as the recent Omicron raises the possibility of booster doses to achieve adequate protection. In Brazil, the CoronaVac (Sinovac, Beijing, China) vaccine was used; however, it is important to assess the immune response to this vaccine over time. This study aimed to monitor the anti-SARS-CoV-2 antibody responses in those immunized with CoronaVac and SARS-CoV-2 infected individuals. Samples were collected between August 2020 and August 2021. Within the vaccinated cohort, some individuals had a history of infection by SARS-CoV-2 prior to immunization, while others did not. We analyzed RBD-specific and neutralizing-antibodies. Anti-RBD antibodies were detected in both cohorts, with a peak between 45–90 days post infection or vaccination, followed by a steady decline over time. In those with a previous history of COVID-19, a higher, longer, more persistent response was observed. This trend was mirrored in the neutralization assays, where infection, followed by immunization, resulted in higher, longer lasting responses which were conditioned on the presence of levels of RBD antibodies right before the vaccination. This supports the necessity of booster doses of CoronaVac in due course to prevent serious disease. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the compliance of the practice with the evidence-based criteria in relation to interventions developed to improve the immunosuppressive adherence of adults in postkidney transplantation. Method: A best practice implementation project, based on the Joanna Briggs Institute's Practical Application of Clinical Evidence Systemand Getting Research into Practice audit tool for promoting change in health practice, was conducted. A baseline and a follow-up audit were conducted in a kidney transplant clinic, including a sample of kidney transplant patients with a maximum of 30 days postoperatively, and health professionals working in the post-transplant period. Results: The basic audit revealed that the parameters related to the professionals' knowledge did not reach adequate compliance; the involvement of patients in strategies to overcome barriers that interfere with nonadherence; guidelines for specific therapeutic regimens for patients and the prescription of immunosuppressants according to the patient's routine. To solve the identified weaknesses, training strategies were implemented with the professionals, follow-up by telephone contact with the patients and the elaboration and distribution of an educational booklet with guidance on the use of immunosuppressants, leading to an increase from 50 to 87.5% of conformity in the evaluated service. Conclusion: The evidence implementation project provided improvements in clinical practice behaviors. It demonstrated that there are strategies that facilitate the implementation of evidence regarding the promotion of interventions to improve immunosuppressive adherence. Additional audits are still needed to improve and assess the quality of interventions promoted by professionals regarding drug adherence in the post-transplant period, as well as to verify the behavior of patients, ensuring that the project will be maintained and supported. [ABSTRACT FROM AUTHOR]

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BACKGROUND Bemisia tabaci (Genn.) (Hemiptera: Aleyrodidae) was observed to have completed its reproductive cycle from the egg to the adult on maize ( Zea mays L.). Field and screenhouse studies were carried out to investigate the durability of this putative and unprecedented adaptation to a grass host. RESULTS Analysis of the mitochondrial COI gene sequence identified the maize-associated B. tabaci as the exotic B biotype (major clade North Africa-Mediterranean-Middle East). Results showed that whiteflies migrated from soybean crops and successfully established in maize plants. Females exhibited a preference for oviposition primarily on the first and second leaves of maize, but were also able to colonise developing leaves. A high, natural infestation on maize (193.3 individuals, all developmental stages) was observed within a 7.1 cm2 designated 'observation area'. Whiteflies collected from naturally infested maize leaves and allowed to oviposit on maize seedlings grown in a screenhouse developed from egg to adulthood in 28.6 ± 0.2 days. CONCLUSION This is the first report of the B biotype completing its development on maize plants. This surprising anomaly indicates that the B biotype is capable of adapting to monocotyledonous host plants, and importantly, broadens the host range to include at least one species in the Poaceae. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The objective of this study was to determine the toxicity of the nine synthetic dienamides against the insect pestDiaphania hyalinata(melonworm) and the selectivity of these substances for the predatorSolenopsis saevissima(fire ant). Four bioassays were conducted. To begin with, the dienamides that caused high mortality ofD. hyalinatahave been selected. In the second bioassay the dose-mortality curves of the selected dienamides have been constructed. In the third bioassay, the survival curves forD. hyalinataand the elapsed time to kill 50% of their population have been determined. In the fourth biological test, the selectivity of the substances to the predatorS. saevissimahas been evaluated. The most active (2E,4E)-N-butylhexa-2,4-dienamide3dhas killed 95% of the melonworm,D. hyalinata, and less than 10% of the natural enemyS. saevissima. The results presented by this compound are superior to the outcome displayed by the commercial insecticide Malathion®. Three of the dienamides prepared in this manuscript have proven to be selective in killing the pest, but not the beneficial insect. [ABSTRACT FROM PUBLISHER]

Background: Rio de Janeiro (RJ) has been of major importance for the epidemiology of dengue viruses (DENVs) in Brazil. After the DENV1-4 introductions in 1986,1990, 2000 and 2011, respectively, the state has suffered explosive epidemics. We aimed to describe laboratorial, epidemiological and clinical aspects due to the emergence and re-emergence of distinct DENV in a 2-year period. Methods: Suspected dengue cases (n=2833), including 190 fatal cases, were submitted to virus isolation, RT-PCR and non-structural 1 (NS1) antigen capture ELISA, IgM antibody-capture (MAC)-ELISA and IgG-ELISA. Results: Case confirmation was 47.5%. MAC-ELISA confirmed 32.6% of the cases, RT-PCR confirmed 56.3%; DENV was recovered in 33.1% of samples inoculated and NS1 ELISA confirmed 27.5% of the cases. DENV-2 was prevalent in 2010, DENV-1 in 2011 and DENV-4 in 2012. Individuals infected by DENV-3 and over 65 years-old, and children 15 years-old and under infected by DENV-2 had a significantly higher risk of developing a severe disease. Fatal cases confirmed (n=67) were due to DENV-1 (26.8%), DENV-2 (14.9%), DENV-3 (2.9%) and DENV-4 (7.4%). Conclusions: It has been shown here that viral emergences or re-emergences may play different roles in the disease epidemiology, especially when many serotypes co-circulate. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate intake, digestibility, ingestive behaviour, and body weight variation in lambs fed mesquite pod meal (0, 30, 60 and 90%) in substitution of ground corn grains (as-fed basis) in pelleted diets. Twelve Santa Ines×Dorper lambs with average body weight of 25.0±1.8 kg were distributed through three 4×4 Latin Squares consisting of four periods and four treatments. Diets consisted of 30% alfalfa hay and 70% concentrate. The experimental period was 60 days, divided into 15-day periods. The intakes of dry matter (DM), total carbohydrates (TC) and total digestible nutrients (TDN) were not influenced (P>0.05) by the different levels of mesquite pod meal added in substitution of corn. The digestibility coefficients of DM, organic matter (OM), ether extracts (EE), neutral detergent fibre free of ash and protein (NDFap), TC and the TDN decreased linearly (P<0.05) as the level of mesquite pod meal in the diet was increased. Feed efficiency [g DM and neutral detergent fibre (NDF)/hour] was not influenced (P>0.05) by the mesquite pod meal levels; contrastingly, this feedstuff caused a reduction of 12.13 and 1.9 g in rumination efficiency (g DM and NDF/hour, respectively) for every percentage unit added. The average weight gain showed quadratic behaviour (P<0.05) as a result of the substitution level, and maximum weight gain was estimated at 275.9 g/day at the substitution level of 47.5%. [ABSTRACT FROM AUTHOR]

Simple Summary: The nutrients requirements of dairy cattle is the most used system to formulate dairy cattle diets. However, these guidelines were developed based on research using mostly purebred Holstein in temperate conditions and did not determine nutrient requirements of crossbred Holstein × Gyr or Gyr animals raised in a tropical environment. Studies conducted in tropical conditions demonstrated that breed largely affected the nutrient requirements of crossbred and Gyr cattle, which limits the use of this system. Our objective was to evaluate the effects of two feeding levels and three breed compositions on nutrient intake, digestibility, performance, and methane emissions of prepubertal (10-month-old) dairy heifers. We observed that feeding diets to allow gains of 400 and 800 g/day resulted in greater daily gain than the formulated, overestimating the nutritional requirements of the heifers. Overall, breed composition did not affect dry matter intake, but it did result in differences in nutrients digestibility coefficients and feed efficiency. Feeding prepubertal heifers above maintenance requirements was the main driver in reducing CH4 intensity in confinement conditions. The dairy Nutrients Requirements of Cattle (NRC) was developed using data from purebred Holsteins and it might not accurately predict the performance of crossbred cattle. Our objectives were to evaluate the effects of two feeding levels (FLs) and three breed compositions (BCs) on nutrient intake, digestibility, performance, and methane (CH4) emissions of prepubertal dairy heifers. We used thirty-six heifers from three BCs: purebred Holstein (H), purebred Gyr (G), and F1 Holstein × Gyr (HG). Each BC had 12 animals and the experiment was designed as twelve incomplete three by three Latin squares, in a factorial arrangement three by two, with three BCs and two FLs (400 and 800 g/day). Total tract nutrient digestibility was determined using total fecal collection and DMI was individually measured. The data were analyzed using the PROC MIXED in SAS. Dry matter intake of all nutrients increased from the medium to high feeding level and the nutrients digestibility coefficients did differ among BCs. Achieved body weight gain in the medium FL treatment was greater than those predicted using the NRC, suggesting that crossbred and Gyr heifers have similar performance to Holsteins. Breed composition does not influence body weight gain of confined dairy heifers, but Holstein heifers fed a medium FL had higher feed efficiency and reduced CH4 emissions intensity. [ABSTRACT FROM AUTHOR]