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Plant protection unmanned aerial vehicles (UAVs) have become popular in mountain orchards, but due to the differences in planting structures, the chances of heavy spraying, missed spraying and pesticide drift are increasing. To mitigate the adverse effects of these phenomena, it is necessary to clarify the effective deposition range of aerial spray droplets. This study proposed an effective spray swath determination method for the effective spraying range of mountainous orchards with UAVs equipped with a mist nozzle (bilateral 1% coverage). This approach focused on exploring the effects of flight height (unidirectional flight modes of 2, 3 and 4 m), spray nozzle atomization performance (reciprocating flight modes of 20, 30 and 40 µm) and flight route (treetop flying and inter-row flying) on the spraying range in a mountain setting. In addition, the study analysed the relationship between the droplet-size spectrum and the effective swath position. The results showed that it is feasible to use the bilateral 1% coverage evaluation method to determine the effective spray swath of a UAV adapted with a mist nozzle for aerial operation in a mountainous Nangguo Pear orchard. With the increase in UAV flight height (2-4 m), the effective unidirectional spray swath also increased, and with the increase in atomization level (20-40 mm), the effective reciprocating spray swath showed a decreasing trend. Moreover, the average effective swath width measured by the UAV for treetop flight was greater than that measured for interrow flight. The study also found that the proportion of small droplets (droplet size less than 100 µm) below the UAV route was lower (approximately 50%) than along the sides of the route (approximately 80%), and the spray swath was not symmetrically distributed along the flight route but shifted laterally by approximately 3 to 4 m in the downhill direction. [ABSTRACT FROM AUTHOR]

The tuberculosis (TB) burden remains a significant global public health concern, especially in less developed countries. While pulmonary tuberculosis (PTB) is the most common form of the disease, extrapulmonary tuberculosis, particularly intestinal TB (ITB), which is mostly secondary to PTB, is also a significant issue. With the development of sequencing technologies, recent studies have investigated the potential role of the gut microbiome in TB development. In this review, we summarized studies investigating the gut microbiome in both PTB and ITB patients (secondary to PTB) compared with healthy controls. Both PTB and ITB patients show reduced gut microbiome diversity characterized by reduced Firmicutes and elevated opportunistic pathogens colonization; Bacteroides and Prevotella were reported with opposite alteration in PTB and ITB patients. The alteration reported in TB patients may lead to a disequilibrium in metabolites such as short-chain fatty acid (SCFA) production, which may recast the lung microbiome and immunity via the "gut-lung axis". These findings may also shed light on the colonization of Mycobacterium tuberculosis in the gastrointestinal tract and the development of ITB in PTB patients. The findings highlight the crucial role of the gut microbiome in TB, particularly in ITB development, and suggest that probiotics and postbiotics might be useful supplements in shaping a balanced gut microbiome during TB treatment. [ABSTRACT FROM AUTHOR]

The centrosome regulates mammalian meiosis by affecting recombination, synapsis, chromosome segregation, and spermiogenesis. Cep72 is one of the critical components of the centrosome. However, the physiological role of Cep72 in spermatogenesis and fertility remains unclear. In this study, we identify Cep72 as a testis-specific expression protein. Although Cep72 knockout mice were viable and fertile, their sperms were morphologically abnormal with incomplete flagellum structures. Transcriptome analysis reveals significant differences in six genes (Gm49527, Hbb-bt, Hba-a2, Rps27a-ps2, Gm29647, and Gm8430), which were not previously associated with spermatogenesis. Overall, these results indicate that Cep72 participates in regulating sperm morphology and yet is dispensable for fertility in mice. [ABSTRACT FROM AUTHOR]

The article titled "Retraction Note: The spillover of tourism development on CO2 emissions: a spatial econometric analysis" has been retracted by the publisher due to concerns regarding the peer review process, inappropriate references, nonstandard phrases, and the article's alignment with the journal's scope. The authors of the article, Yan Jiaqi, Yu Ziqi, Li Tingting, Song Yang, and Brian Sheng Xian Teo, have not responded to correspondence regarding the retraction. Springer Nature, the publisher, remains neutral regarding jurisdictional claims and institutional affiliations. [Extracted from the article]

Nanoporous structures with a critical dimension comparable to or smaller than the phonon mean free path have demonstrated significant thermal conductivity reductions that are attractive for thermoelectric applications, but the presence of various geometric parameters complicates the understanding of governing mechanisms. Here, we use a ray tracing technique to investigate phonon boundary scattering phenomena in Si nanoporous structures of varying pore shapes, pore alignments, and pore size distributions, and identify mechanisms that are primarily responsible for thermal conductivity reductions. Our simulation results show that the neck size, or the smallest distance between nearest pores, is the key parameter in understanding nanoporous structures of varying pore shapes and the same porosities. When the neck size and the porosity are both identical, asymmetric pore shapes provide a lower thermal conductivity compared with symmetric pore shapes, due to localized heat fluxes. Asymmetric nanoporous structures show possibilities of realizing thermal rectification even with fully diffuse surface boundaries, in which optimal arrangements of triangular pores show a rectification ratio up to 13 when the injection angles are optimally controlled. For symmetric nanoporous structures, hexagonal-lattice pores achieve larger thermal conductivity reductions than square-lattice pores due to the limited line of sight for phonons. We also show that nanoporous structures of alternating pore size distributions from large to small pores yield a lower thermal conductivity compared with those of uniform pore size distributions in the given porosity. These findings advance the understanding of phonon boundary scattering phenomena in complex geometries and enable optimal designs of artificial nanostructures for thermoelectric energy harvesting and solid-state cooling systems. [ABSTRACT FROM AUTHOR]

Climate change and tourism's interaction and vulnerability have been among the most hotly debated topics recently. In this context, the study focuses on how CO2 emissions, the primary cause of global warming and climate change, respond to changes in tourism development. In order to do so, the impact of tourism development on CO2 emissions in the most visited countries is investigated. A panel data from 2000 to 2017 for top 70 tourist countries are analysed using a spatial econometric method to investigate the spatial effect of tourism on environmental pollution. The direct, indirect, and overall impact of tourism on CO2 emissions are estimated using the most appropriate generalized nested spatial econometric (GNS) method. The findings reveal that tourism has a positive direct effect and a negative indirect effect; both are significant at the 1% level. The negative indirect effect of tourism is greater than its direct positive effect, implying an overall significantly negative impact. Further, the outcome of financial development and CO2 emissions have an inverted U-shaped and U-shaped relationship in direct and indirect impacts. Population density, trade openness, and economic growth significantly influence environmental pollution. In addition, education expenditure and infrastructure play a significant moderating role among tourism and environmental pollution. The results have important policy implications as they establish an inverted-U-shaped relationship among tourism and CO2 emissions and indicate that while a country's emissions initially rise with the tourism industry's growth, it begins declining after a limit. [ABSTRACT FROM AUTHOR]

Population data are key indicators of policymaking, public health, and land use in urban and ecological systems; however, traditional censuses are time-consuming, expensive, and laborious. This study proposes a method of modelling population density estimations based on remote sensing data in Hefei. Four models with impervious surface (IS), night light (NTL), and point of interest (POI) data as independent variables are constructed at the township scale, and the optimal model was applied to pixels to obtain a finer population density distribution. The results show that: (1) impervious surface (IS) data can be effectively extracted by the linear spectral mixture analysis (LSMA) method; (2) there is a high potential of the multi-variable model to estimate the population density, with an adjusted R2 of 0.832, and mean absolute error (MAE) of 0.420 from 10-fold cross validation recorded; (3) downscaling the predicted population density from the township scale to pixels using the multi-variable stepwise regression model achieves a more refined population density distribution. This study provides a promising method for the rapid and effective prediction of population data in interval years, and data support for urban planning and population management. [ABSTRACT FROM AUTHOR]

The trends toward higher power, higher frequency, and smaller scale electronics are making heat dissipation ever more challenging. Passive thermal management based on high thermal conductivity materials or through-silicon vias (TSVs) may not provide sufficient cooling for hot spots reaching 1 kW cm−2, and active thermal management by thermoelectric cooling (TEC) may require large power consumption or suffer from a large off-state thermal resistance of thermoelectric materials. Here we address these issues by integrating a holey silicon-based TEC with a TSV that directly draws heat from a hot spot to combine active and passive cooling approaches. Our simulations of the TSV-integrated TEC demonstrate exceptional cooling performance, which reduces the hot spot temperature from 154 °C to 68 °C while dissipating a heat flux of 1 k W cm−2 and consuming 0.5 W for TEC operation. The off-state hot spot temperature, 154 °C, is 24 °C lower than that of the same TEC with no TSV, and the on-state hot spot temperature, 68 °C, is 67 °C lower than that of the same TEC with no TSV. We also investigate the cooling prospects of metal-filled holey silicon by modeling the electron–phonon coupling and size dependent transport phenomena, which can further increase the thermal conductivity anisotropy and improve the TEC performance depending on the metal-to-silicon interfacial resistance. These results show the combined passive and active cooling in TSV-integrated TEC offers effective hot spot thermal management solutions for advanced electronics. [ABSTRACT FROM AUTHOR]