Efecto de la radiación UV-C y del agua caliente en el contenido de calcio y calidad poscosecha de manzanas

To increase the storage shelf life of "Red Delicious" and "Golden Delicious" apples they were treated with UV-C irradiation at doses of 0, 5 and 15 min irradiation at 1.435 x 10E-4 W/square cm and with hot water containing 4% CaCl2 at four levels (control, dipping at 25 deg C for 10 min, dipping at 38 deg C for 5 min and dipping in 54 deg C for 1 min) in a factorial design with 4 replicates. The results showed that UV-C irradiation and dipping of fruit in hot water increased the storage life and improved fruit quality factors in "Red Delicious" and "Golden Delicious" apples at the end of cold storage. Both UV-C and hot water treatments decreased pH and total soluble solids/titratable acids ratio and increased fruit titratable acids and firmness. UV-C and hot water treatment increased fruit Ca content during storage. The results showed that UV-C and hot water treatment can retard fruit ripening and maintain fruit quality in cold storage. These treatments can also increase Ca concentration of fruit flesh and thus increase the nutritional value of the apples.Con el fin de prolongar el periodo de vida útil durante la conservación frigorífica de manzanas "Red Delicious" y "Golden Delicious", éstas se trataron con radiación UV-C en tres dosis (0, 5 y 15 min de irradiación a 1,435 x 10E-4 W/cm cuadrado) y agua caliente con CaCl2 al 4% en cuatro niveles (control 0, inmersión a 25 grados C 10 min, 38 grados C 5 min ó 54 grados C 1 min), en un diseño factorial con 4 repeticiones por tratamiento. La irradiación con UV-C y la inmersión de los frutos en agua caliente permitió alargar el periodo de conservación y mejoró la calidad de manzanas "Red Delicious" y "Golden Delicious" tras el almacenamiento en frío. Ambos tratamientos aumentaron la acidez titulable y la firmeza de los frutos, también disminuyeron el pH y la relación sólidos solubles/acidez. El tratamiento con UV-C y agua caliente incrementó el contenido en calcio de los frutos durante el almacenamiento. Los resultados muestran que estos tratamientos pueden retrasar los procesos de maduración de los frutos y mantener su calidad durante el almacenamiento frigorífico, así como aumentar el contenido en Ca de la pulpa del fruto y por tanto incrementar su valor nutricional

A novel approach to study laser induced void array formation in fused silica

This study investigated multi-void formation in fused silica using high resolution Finite-Difference-Time-Domain (FDTD) simulations. Despite extensive research dedicated to understanding the mechanisms behind multi-void formation in materials, the fundamental aspects and mechanisms governing self-void array formation in dielectrics and polymers remain poorly understood. By modeling the voids as concentric spheres with densified shells and simulating the laser interaction with the voids, we showed that void array generation in fused silica is a linear mechanism. This study provides valuable insight into the mechanism behind the formation of void arrays in fused silica.Comment: arXiv admin note: substantial text overlap with arXiv:2305.0297

Histological characterisation of the skin of the Paraechinus hypomelas, Brandt, 1836 (Erinaceidae: Eulipotyphla)

Background: The current study represents the first description of the histological characterisations of the normal skin of Brandt’s hedgehog (paraechinus hypomelas). Materials and methods: Skin samples were collected from abdomen, back, nostril and cloacal regions. Results: The skin consisted of 3 layers including epidermis, dermis and hypodermis. The epidermis was covered by a layer of keratinised squamous epithelium mainly in the back region, but the skin keratinisation was present with a little amount or may was absent in other regions. Histologically, the total thickness of skin was maximum on the back and minimum on the cloacal regions. The epidermis consisted of 4 layers and stratum lucidum was absent in all regions. Beneath the epidermis, the dermis layer was constituted of dense connective tissue in which the hair follicles, sweat glands, sebaceous glands, arrector pilli muscles and blood vessels were present. The sweat and sebaceous glands were more populated in the nostril region. The hair follicles were located in the epidermal and dermal regions. Vibrissae were only in the nostrils region and characterised from other hairs by their large and well innervated hair follicle which was surrounded by the blood sinus. Conclusions: The present findings show that in Brandt’s hedgehog (paraechinus hypomelas) the back and cloacal regions have thickest and thinnest skin respectively as compared to the nostril and abdominal regions. In addition, sebaceous and sweat glands were mainly populated in the nostril regio

A simple thermal treatment synthesis and characterization of Ni-Zn ferrite (Ni0.5Zn0.5Fe2O4) nanocrystals

Cubic structured nickel-zinc ferrite nanoparticles (Ni0.5Zn0.5Fe2O4) have been synthesized by thermal treatment method. This simple procedure employed an aqueous solution containing only metal nitrates as precursors, polyvinyl pyrrolidone as a capping agent, and deionized water as a solvent. The solution was thoroughly stirred for 2 hour, dried at 353 K for 3 hour, the dried material crushed into powder and calcined the powder at 873 K to remove organic substances and crystallize the particles. The microstructure properties of the prepared ferrite nanoparticles were measured using FTIR, XRD, TEM, and EDX and the magnetic properties were determined using VSM and EPR. The average particle size increased from 7 to 22 nm with the increase of calcination temperature from 723 to 873 K. The saturation magnetization, coercivity field, and g-factor increased respectively from 24 emu/g, 11 G, and 2.0673at 723 K to 38 emu/g, 60 G, and 2.1227 at 873 K. This method offers simplicity, a low cost, and an environmentally friendly operation since it produces no by-product effluents

Triple-drug treatment is effective for lymphatic filariasis microfilaria clearance in Samoa

Following the first triple-drug mass drug administration (MDA) for lymphatic filariasis in Samoa in 2018, unexpected persistence of microfilaria (Mf) positivity in 18 (15%) of 121 antigen-positive persons was observed in a nationwide household survey 1–2 months later. Of the 18 Mf positive persons, 14 reported taking the MDA, raising concerns about MDA efficacy. In 2019, 5–6 months after the 2018 survey, a monitored treatment study was done to evaluate directly observed weight-based treatment in these Mf positive individuals. Mf presence and density were assessed before and 7 days after treatment, using 1 mL membrane filtered venous blood, and 60 uL thick blood films on slides prepared from venous or fingerprick blood. All 14 participants were still Mf positive on filters from venous blood pre-treatment samples, but two were negative by slide made from the same samples. Mf were cleared completely by day 7 in 12 of 13 participants followed up, and by day 30 in the remaining participant. Filtered blood using EDTA samples (to reduce clumping of Mf) is preferred over slides alone for improving the likelihood of detecting Mf and estimating their density. The triple-drug MDA strategy was effective at clearing Mf when given and taken at the correct dose

Probiotic Bacillus subtilis 29,784 improved weight gain and enhanced gut health status of broilers under necrotic enteritis condition

The study investigated the benefit of a Bacillus subtilis probiotic (Bs 29,784) in necrotic enteritis (NE)-challenged broilers. Four treatments were performed with 312 male day-old Ross 308 reared in floor pens from day 0 to day 35: 2 groups fed control diet without or with NE challenge (CtrlNC and CtrlNE); 2 groups fed probiotic and antibiotic supplements in the control diet with NE challenge (ProNE and AntNE). Necrotic enteritis challenge procedures commenced with inoculation of Eimeria spp 1 mL/bird per os at day 9 and Clostridium perfringens EHE-NE18 (approximately 108 cfu/mL) 1 mL/bird per os at day 14 and day 15. Performance parameters were measured on day 16 and day 35. Lesion, cecal microbiota, and jejunal gene expression were analyzed on day 16. Necrotic enteritis challenge significantly suppressed the performance parameters compared with CtrlNC: 27% weight gain reduction, 11 points feed conversion ratio (FCR) increase at day 16, and 12% weight gain reduction, 5-point FCR increase at day 35. By day 35, ProNE and AntNE treatments enabled significantly higher weight gain (4 and 9%, respectively) than CtrlNE. Compared with CtlrNE and contrary to AntNE, ProNE treatment exhibited upregulation of genes coding for tight junctions proteins (CLDN1, JAM2, TJP1), cytokines (IL12, interferon gamma, TGFβ), and Toll-like receptors (TLR5, TLR21) suggesting enhanced immunity and intestinal integrity. 16S NGS analysis of cecal microbiota at day 16 showed a decreased alpha diversity in challenged groups. Principal component analysis of operational taxonomic unit (OTU) abundance revealed that ProNE and AntNE grouped closely while both distantly from CtrlNC and CtrlNE, which were separately grouped, indicating the similar effects of ProNE and AntNE on the OTU diversity that were however different from both CtrlNC and CtrlNE. Microbiota analysis revealed an increase of genera Faecalibacterium, Oscillospira, and Butyricicoccus; and a decrease of genera Ruminococcus, Lactobacillus, and Bacteroides; and an increase of the Firmicutes-to-Bacteroidetes ratio in ProNE and AntNE groups compared with the CtlrNE group. It is concluded that Bs 29,784 may enable improved health of broiler chickens under NE conditions thus performance implications

Resistance of different tomato cultivars to the two-spotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae)

Two-spotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae), is one of the most important pests of tomato crops. Using resistant cultivars is a useful control method against the pest in integrated pest management programs. In this study, resistance of the tomato cultivars Super Chief, Super Strain B, Korral, Khorram, HAS 2274, Super H, Calji, Early Urbana Y and Mobil to two-spotted spider mite were evaluated under laboratory conditions at 25 ± 2 °C, 60 ± 10% R.H. and a photoperiod of 16: 8 (L: D).The shortest pre-adult stage was recorded on Super Strain B. Female life span ranged from 26.47 to 30.40 days, on Super Chief and Early Urbana Y, respectively. The intrinsic rate of increase (rm) was from 0.091 to 0.163 day-1 which the lowest rm was observed on Super Chief and the highest rm was on Super Strain B. The lowest net reproductive rate (R0) and finite rate of increase (λ) belonged to Super Chief cultivar. Super Chief cultivar showed the highest antibiosis resistance against the two-spotted spider mite

A community survey of coverage and adverse events following country-wide triple-drug mass drug administration for lymphatic filariasis elimination, Samoa 2018

The Global Programme to Eliminate Lymphatic Filariasis has made considerable progress but is experiencing challenges in meeting targets in some countries. Recent World Health Organization guidelines have recommended two rounds of triple-drug therapy with ivermectin, diethylcarbamazine (DEC), and albendazole (IDA), in areas where mass drug administration (MDA) results with two drugs (DEC and albendazole) have been suboptimal, as is the case in Samoa. In August 2018, Samoa was the first country in the world to implement countrywide triple-drug MDA. This paper aims to describe Samoa’s experience with program coverage and adverse events (AEs) in the first round of triple-drug MDA. We conducted a large cross-sectional community survey to assess MDA awareness, reach, compliance, coverage and AEs in September/October 2018, 7–11 weeks after the first round of triple-drug MDA. In our sample of 4420 people aged ≥2 years (2.2% of the population), age-adjusted estimates indicated that 89.0% of the eligible population were offered MDA, 83.9% of the eligible population took MDA (program coverage), and 80.2% of the total population took MDA (epidemiological coverage). Overall, 83.8% (2986/3563) reported that they did not feel unwell at all after taking MDA. Mild AEs (feeling unwell but able to do normal everyday things) were reported by 13.3% (476/3563) and moderate or severe AEs (feeling unwell and being unable to do normal everyday activities such as going to work or school) by 2.9% (103/3563) of participants. This study following the 2018 triple-drug MDA in Samoa demonstrated a high reported program awareness and reach of 90.8% and 89.0%, respectively. Age-adjusted program coverage of 83.9% of the total population showed that MDA was well accepted and well tolerated by the community

Supporting elimination of lymphatic filariasis in Samoa by predicting locations of residual infection using machine learning and geostatistics

The global elimination of lymphatic filariasis (LF) is a major focus of the World Health Organization. One key challenge is locating residual infections that can perpetuate the transmission cycle. We show how a targeted sampling strategy using predictions from a geospatial model, combining random forests and geostatistics, can improve the sampling efficiency for identifying locations with high infection prevalence. Predictions were made based on the household locations of infected persons identified from previous surveys, and environmental variables relevant to mosquito density. Results show that targeting sampling using model predictions would have allowed 52% of infections to be identified by sampling just 17.7% of households. The odds ratio for identifying an infected individual in a household at a predicted high risk compared to a predicted low risk location was 10.2 (95% CI 4.2–22.8). This study provides evidence that a ‘one size fits all’ approach is unlikely to yield optimal results when making programmatic decisions based on model predictions. Instead, model assumptions and definitions should be tailored to each situation based on the objective of the surveillance program. When predictions are used in the context of the program objectives, they can result in a dramatic improvement in the efficiency of locating infected individuals

Evaluating Molecular Xenomonitoring as a Tool for Lymphatic Filariasis Surveillance in Samoa, 2018–2019

Molecular xenomonitoring (MX), the detection of filarial DNA in mosquitoes using molecular methods (PCR), is a potentially useful surveillance strategy for lymphatic filariasis (LF) elimination programs. Delay in filarial antigen (Ag) clearance post-treatment is a limitation of using human surveys to provide an early indicator of the impact of mass drug administration (MDA), and MX may be more useful in this setting. We compared prevalence of infected mosquitoes pre- and post-MDA (2018 and 2019) in 35 primary sampling units (PSUs) in Samoa, and investigated associations between the presence of PCR-positive mosquitoes and Ag-positive humans. We observed a statistically significant decline in estimated mosquito infection prevalence post-MDA at the national level (from 0.9% to 0.3%, OR 0.4) but no change in human Ag prevalence during this time. Ag prevalence in 2019 was higher in randomly selected PSUs where PCR-positive pools were detected (1.4% in ages 5–9; 4.8% in ages ≥10), compared to those where PCR-positive pools were not detected (0.2% in ages 5–9; 3.2% in ages ≥10). Our study provides promising evidence for MX as a complement to human surveys in post-MDA surveillance