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Randomized Branch Sampling (RBS) is a multistage sampling procedure using natural branching in order to select samples for the estimation of tree characteristics. Usually, sampling units are selected with unequal probabilities. Conventional RBS uses sampling with replacement (SWR) for repeated sampling on the first stage, and the sample size equals 1 on all subsequent stages, thus resulting in n so-called sample paths. When the sampling fraction is large multiple selections of first stage units are likely. Sampling without replacement (SWOR) at the first stage is an alternative that is expected to increase efficiency of the procedure. In this case, the second stage sample size m must be larger than 1 to enable unbiased variance estimation. In the present study, a theoretical and an empirical comparison of the conventional RBS and the SWOR variant was accomplished. Requiring a certain precision of the RBS estimation, the conventional RBS method is mostly more time-consuming than the variant with SWOR at the first stage. Only if m = 1 is chosen as second stage sample size for the SWOR RBS, this is often more time-consuming. In those cases, conventional RBS is up to 5% cheaper. In general, the larger m is, the more expensive is conventional RBS compared with the variant with swor at the first stage. The smaller the ratio of the variance between the primary units to the total variance of the estimate, the larger is the advantage of the SWOR variant. Generally, it can be shown that the gain of efficiency by SWOR is larger in case of weak correlations between auxiliary and target variable.

Fruit size can act as a physical barrier providing refuge for larvae of pest Anastrepha species against parasitoid attack. Therefore, the aim of this study was to evaluate the influence of fruit size in six fruit species infested by Anastrepha larvae on the parasitism of Diachasmimorpha longicaudata after its augmentative release. About 1500 parasitoids were weekly released in disturbed wild vegetation patches. Fruit sampling was performed at the Coastal Lowlands of the Soconusco Region, southeastern Mexico, between June 2021 and October 2022. Overall, 310 ripe fruits belonging to grapefruit, creole mamey (large-size fruits), sweet orange, creole mango, wild guava (medium-size fruits), and wild hog plum (small-size fruit) were collected. The length, frontal width, lateral width and pulp thickness of all sampled fruits were measured. Such physical characteristics are indicators of the fruit size. Fruit collection was performed 48 h after release. Results indicated an inverse correlation between fruit size and parasitism, with a significant r2 value higher than 75%. Host larvae in all fruits were parasitised only by D. longicaudata. The highest mean parasitism, which exceeded 90%, was recorded on hog plum and the lowest, below 20%, on Citrus spp. and mamey. Results corroborated the influence of host fruit size on parasitism levels by D. longicaudata regardless of its large-scale, open-field releases. Augmentative releases of D. longicaudata can be focused on wilderness areas with prevalence of medium-size to small-size Anastrepha host fruits. This would encourage long-term sustainable conservation of released parasitoid populations. [ABSTRACT FROM AUTHOR]

Aim: The present study aimed to investigate the effects of a single bout of resistance exercise on mitophagy in human skeletal muscle (SkM). Methods: Eight healthy men were recruited to complete an acute bout of one‐leg resistance exercise. SkM biopsies were obtained one hour after exercise in the resting leg (Rest‐leg) and the contracting leg (Ex‐leg). Mitophagy was assessed using protein‐related abundance, transmission electron microscopy (TEM), and fluorescence microscopy. Results: Our results show that acute resistance exercise increased pro‐fission protein phosphorylation (DRP1Ser616) and decreased mitophagy markers such as PARKIN and BNIP3L/NIX protein abundance in the Ex‐leg. Additionally, mitochondrial complex IV decreased in the Ex‐leg when compared to the Rest‐leg. In the Ex‐leg, TEM and immunofluorescence images showed mitochondrial cristae abnormalities, a mitochondrial fission phenotype, and increased mitophagosome‐like structures in both subsarcolemmal and intermyofibrillar mitochondria. We also observed increased mitophagosome‐like structures on the subsarcolemmal cleft and mitochondria in the extracellular space of SkM in the Ex‐leg. We stimulated human primary myotubes with CCCP, which mimics mitophagy induction in the Ex‐leg, and found that BNIP3L/NIX protein abundance decreased independently of lysosomal degradation. Finally, in another human cohort, we found a negative association between BNIP3L/NIX protein abundance with both mitophagosome‐like structures and mitochondrial cristae density in the SkM. Conclusion: The findings suggest that a single bout of resistance exercise can initiate mitophagy, potentially involving mitochondrial ejection, in human skeletal muscle. BNIP3L/NIX is proposed as a sensitive marker for assessing mitophagy flux in SkM. [ABSTRACT FROM AUTHOR]

The chilled adult technique is a suitable strategy for the mass - release of insects for the area - wide management of insect pests. Chilling may have undesirable effects on the released insects. The relationship between physical traits and the effects of cold-induced lethargy on the fitness of Diachasmimorpha longicaudata has not been fully explored. In the present study, we evaluated the relationship between weight, size, and water and lipid content in D. longicaudata subjected to cold-induced lethargy at 9, 6, and 3°C, and the effects of cold induction on the survival, flight ability, and fecundity of parasitoid adults. During gradual chilling from 15°C to 3°C over a 45 min period, we observed that most wasps became lethargic at 9°C. The tibias of wasps that became lethargic at 3°C were larger than those of parasitoids that became lethargic at 9 and 6°C. Body water and lipid contents were higher in lethargic females chilled at 3°C, but no differences were observed in males. Lethargic males experienced reduced flight ability compared with the control, whereas fecundity was reduced only in lethargic females that had been exposed to 3°C. The survival rate was lower in both sexes. Our results suggest that greater body size and higher water and lipid contents delay the onset of cold-induced lethargy, but do not prevent negative effects on survival, fecundity, and flight ability in D. longicaudata. This study will help the advancement of parasitoid-release field programmes that use the chilled adult technique. [ABSTRACT FROM AUTHOR]

BACKGROUND: Improving the mating competitiveness and survival of sterile males are direct means to increase the effectiveness of the sterile insect technique (SIT). Some insecticide growth regulators, such as the juvenile hormone analogue (JHA) methoprene, have been used to improve the mating competitiveness of male tephritid flies by reducing their sexual maturation period. However, the application of methoprene reduces fly resistance to stress and decreases survival. Here, we compared the effects of methoprene and pyriproxyfen (PPF), another JHA, in Anastrepha ludens males. PPF is an insect growth regulator that exhibits higher negative effects on the larval molting process than methoprene or natural juvenile hormone. Both compounds were administered at two doses (0.05% and 0.10%) via the male diet immediately after emergence. RESULTS: Our results show that both PPF and methoprene reduced male sexual maturation. However, PPF‐treated males exhibited a shorter maturation period and obtained more matings at a given age than methoprene‐treated males. No significant differences were observed between the two PPF doses tested (0.05% and 0.10%). Male survival was equally reduced by the two compounds. CONCLUSION: Our results demonstrate that PPF accelerated sexual development without reducing the mating propensity of sterile male flies and can be used as a suitable alternative for methoprene. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The authors compared the effects of bodyweight resistance training at moderate- or high-speed conditions on muscle power, velocity of movement, and functional performance in older females. In a randomized, single-blinded noncontrolled trial, participants completed 12 weeks (three sessions/week) of bodyweight resistance training at high (n = 14; age = 70.6 ± 4.3 years) or moderate (n = 12; age = 72.8 ± 4.2 years) speeds. Data were analyzed with an analysis of variance (Group × Time) with α level set at <.05. After the intervention, timed up and go test performance (p <.05) and the rising from a chair test mean (22.4%) and maximal velocity (28.5%), mean (24.4%) and maximal power (27.7%), normalized mean (25.1%), and normalized maximal power (28.5%) increased in the high-speed group (p <.05). However, the moderate-speed group achieved no improvements (Δ6.7–14.4%; p >.2). The authors conclude that high-speed bodyweight resistance training is an effective and economically practical strategy to improve the functional capacity of older women relevant to daily life activities. [ABSTRACT FROM AUTHOR]