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2022 ◽  
Vol 43 (2) ◽  
pp. 561-572
Author(s):  
Izamara Marzolla Gutierres Jacob Machado ◽  
◽  
Luiz Henrique Inacio ◽  
Nátaly Diane Rocha Silva ◽  
Francisco José Teixeira Gonçalves ◽  
...  

Peanut seed can be infected by pathogen diseases that adversely affect the oil crop’s value chain. Ozone gas (O3) can be an alternative for the control of fungal diseases due to its high oxidizing potential. In this study, we investigated the effects of O3 exposure time on physiological and health characteristics of seed from three peanut cultivars. Seed from peanut cultivars Granoleico, IAC OL3, and IAC 503 were analyzed for their health (blotter test) and physiological potential (germination, first count, and seedling length) after exposure to O3 for 0, 1, 8, and 16 h. Peanut seed physiological quality and health differed among cultivars. Exposure of seed from peanut cultivars IAC OL3, IAC 503, and Granoleico to O3 at a rate of 600 mg h-1 did not affect the development of normal seedlings as measured by the first count and germination, but seedling length increased, decreased, or was not affected in cultivars Granoleico, IAC 503, and IAC OL3, respectively. Also, O3 did not eradicate fungal infections in peanut seed treated with O3 at a rate of 600 mg h-1 for up to 16 h, but the incidence of the fungus Rhizopus sp. in seed from cultivars IAC OL3, Granoleico, and IAC 503 increased, decreased or was not affected, respectively, after 8 h.


2022 ◽  
Vol 19 (1) ◽  
Author(s):  
Bin-Hsu Mao ◽  
Yi-Kai Luo ◽  
Bour-Jr Wang ◽  
Chun-Wan Chen ◽  
Fong-Yu Cheng ◽  
...  

Abstract Background Silver nanoparticles (AgNPs) are considered a double-edged sword that demonstrates beneficial and harmful effects depending on their dimensions and surface coating types. However, mechanistic understanding of the size- and coating-dependent effects of AgNPs in vitro and in vivo remains elusive. We adopted an in silico decision tree-based knowledge-discovery-in-databases process to prioritize the factors affecting the toxic potential of AgNPs, which included exposure dose, cell type and AgNP type (i.e., size and surface coating), and exposure time. This approach also contributed to effective knowledge integration between cell-based phenomenological observations and in vitro/in vivo mechanistic explorations. Results The consolidated cell viability assessment results were used to create a tree model for generalizing cytotoxic behavior of the four AgNP types: SCS, LCS, SAS, and LAS. The model ranked the toxicity-related parameters in the following order of importance: exposure dose > cell type > particle size > exposure time ≥ surface coating. Mechanistically, larger AgNPs appeared to provoke greater levels of autophagy in vitro, which occurred during the earlier phase of both subcytotoxic and cytotoxic exposures. Furthermore, apoptosis rather than necrosis majorly accounted for compromised cell survival over the above dosage range. Intriguingly, exposure to non-cytotoxic doses of AgNPs induced G2/M cell cycle arrest and senescence instead. At the organismal level, SCS following a single intraperitoneal injection was found more toxic to BALB/c mice as compared to SAS. Both particles could be deposited in various target organs (e.g., spleen, liver, and kidneys). Morphological observation, along with serum biochemical and histological analyses, indicated that AgNPs could produce pancreatic toxicity, apart from leading to hepatic inflammation. Conclusions Our integrated in vitro, in silico, and in vivo study revealed that AgNPs exerted toxicity in dose-, cell/organ type- and particle type-dependent manners. More importantly, a single injection of lethal-dose AgNPs (i.e., SCS and SAS) could incur severe damage to pancreas and raise blood glucose levels at the early phase of exposure.


2022 ◽  
Vol 12 (1) ◽  
Author(s):  
Daifeng Dong ◽  
Maria Ironside ◽  
Emily L. Belleau ◽  
Xiaoqiang Sun ◽  
Chang Cheng ◽  
...  

AbstractMajor Depressive Disorder (MDD) is characterized by increased stress sensitivity. Emerging findings in healthy adults suggest that stress responses within limbic/striatal-prefrontal regions are moderated by sex and unfold over time. Thus, we hypothesized that stress response abnormalities in MDD might be affected by sex and stress exposure time. The Montreal Imaging Stress Task was administered to 124 unmedicated patients with first-episode MDD (76 females) and 243 healthy controls (HC; 137 females) during functional magnetic resonance imaging (fMRI). Based on prior studies, amygdala, hippocampus, medial orbitofrontal cortex (mOFC), nucleus accumbens (NAc) and dorsolateral prefrontal cortex (dlPFC) were selected as a priori regions of interest. In a complementary approach, we probed the effects of stress on the frontoparietal network (FPN) and a network including the amygdala, NAc and anterior cingulate cortex (ACC). Across groups, males exhibited higher dlPFC activity and right FPN amplitude than females. Relative to female HCs, the female MDD group had less deactivation in limbic/striatal regions (amygdala, NAc, hippocampus, Amygdala-NAc-ACC network). Furthermore, unlike female HCs, the female MDD group failed to show a significant increase of deactivation over stress exposure time in the amygdala, mOFC and NAc. Our findings confirm the importance of considering sex differences when investigating neural stress responses. Case-control differences in neural stress responses observed in females (but not males) provide insights into sex differences in the etiology and pathophysiology of depression. The failure to deactivate limbic/NAc regions in depressed females point to dysfunction of adaptive stress responses over stress exposure time.


2022 ◽  
Vol 3 (1) ◽  
Author(s):  
K. Abha Manohar ◽  
Gopal Shukla ◽  
Bidhan Roy ◽  
Sumit Chakravarty

Abstract Background Stevia rebaudiana is an economically important medicinal plant that has generated interest among the growers and pharmacologists in terms of its industrial or pharmaceutical value. For the mass production of the seedlings, easy and convenient techniques are lacking while, micro propagation was reported promising but still out of reach at farm level. The unavailability of quality planting materials due to non-viable seeds is restricting its mass commercial scale cultivation. The present study was therefore attempted to standardize the plant growth regulators and growing media to standardize the vegetative propagation protocol through cuttings for its mass multiplication in Terai region of West Bengal, India. Methods Growing media (soil, FYM, saw dust and sand) as sole and in combination and growth hormones (IAA, IBA and NAA in different concentration and a commercial formulation i.e. Totoroot© with different exposure time) were compared with control (i.e. sole soil and no hormone treatment, respectively) to standardize the nursery protocol of Stevia. Results Sand used as sole was found the best growing media for survival and growth of cuttings while, cuttings treated with commercial growth hormone formulation for 5 mins was best. Cuttings treated with commercial growth hormone formulation performed significantly better in the field with respect to survival, growth and production of leaves. Conclusion The study recommends the use of sole sand media and commercial growth hormone formulation with 5 mins exposure time for mass nursery production of Stevia cuttings in Terai zone of West Bengal due to their better performance both in the nursery and after transplanting in the field.


2022 ◽  
Vol 22 (1) ◽  
Author(s):  
Evelyn Rute Carneiro Maciel ◽  
Eduarda Helena Leandro Nascimento ◽  
Hugo Gaêta-Araujo ◽  
Maria Luiza dos Anjos Pontual ◽  
Andrea dos Anjos Pontual ◽  
...  

Abstract Background This study aimed to investigate the effect of automatic exposure compensation (AEC) of intraoral radiographic systems on the gray values of dental tissues in images acquired with or without high-density material in the exposed region using different exposure times and kilovoltages. The influence of the distance of the high-density material was also investigated. Methods Radiographs from the molar region of two mandibles were obtained using the RVG 6100 and the Express systems, operating at 60 and 70 kV and 0.06, 0.10, and 0.16 s. Subsequently, a titanium implant was inserted in the premolar’s socket and other images were acquired. Using the ImageJ software, two regions of interest were determined on the enamel, coronary dentine, root dentine, and pulp of the first and second molars to obtain their gray values. Results In the RVG 6100, the implant did not affect the gray values (p > 0.05); the increase in kV decreased it in all tissues (p < 0.05), and the exposure time affected only the root dentine and pulp. In the Express, only enamel and coronary dentine values changed (p < 0.05), decreasing with the implant presence and/or with the increase in exposure factors. The distance of the implant did not affect the results (p > 0.05). Conclusions AEC’s performance varies between the radiographic systems. Its effect on the gray values depends not only on the presence or absence of high-density material but also on the kV and exposure time used.


2022 ◽  
Vol 23 (1) ◽  
Author(s):  
Weifeng Li ◽  
Hui Li ◽  
Haiying Wang ◽  
Shunyi Wang

Abstract Background The aim of this study was to discuss the treatment of extra-articular distal humeral shaft fractures using ultrasound-guided preoperative localization of radial nerve. Methods Between May 2010 and December 2019, 56 patients with extra-articular distal humeral shaft fractures were retrospectively reviewed. Twenty eight patients were received examination by using preoperative localization of radial nerve guided by ultrasound-guided preoperative localization (group A) and 28 control patients without ultrasound-guided (group B). All patients were treated surgically for distal humeral shaft fractures by posterior approach techniques. Operative time, radial nerve exposure time, intraoperative bleeding volume, union time and iatrogenic radial nerve palsy rate were compared between the two groups. Elbow function was also evaluated using the Mayo Elbow Performance Score (MEPS). Results A significant difference was observed between the two groups, Operative time (113.25 min vs 135.86 min) (P < 0.001), radial nerve exposure time (20.82 min vs 32.53 min) (P < 0.001), intraoperative bleeding volume (246.80 ml vs 335.52 ml) (P < 0.001). However, iatrogenic radial nerve palsy rate (3.6% vs 7.1%) (P = 0.129), the fracture union time (13.52 months vs 12.96 months) (P = 0.796) and the MEPS score (87.56 vs 86.38) (P = 0.594) were no significantly different in both groups. Conclusions The study demonstrates that ultrasound-guided preoperative localization is an effective approach in the treatment of extra-articular distal humeral shaft fracture by revealing radial nerve, which may help reduce the operative time, radial nerve exposure time and the intraoperative bleeding volume.


2022 ◽  
Vol 92 (2) ◽  
pp. 283
Author(s):  
А.М. Иванов ◽  
А.В. Клочков

A comparative analysis of the initial stages of degradation of ultraviolet and blue LED structures with InGaN / GaN quantum wells is carried out. In the mode of accelerated aging, the structures were subjected to short-term, sequential exposure to currents of 80–190 mA at forward bias. The exposure time did not exceed three hours. There was an increase (up to 20%) in the external quantum efficiency. The most probable physical mechanisms explaining the changes in InGaN / GaN LEDs are presented and possible ways to slow down the aging of UV LEDs are outlined.


Author(s):  
Abijo A.Z. ◽  
Ayannuga O.A. ◽  
Bamigboye O.S.

Background: The state of cortical neurons and astrocytes are pointers to the health of the brain. These cells are morphologically distorted by alcohol exposure. Intrauterine alcohol exposure remains a challenge with perinatal consequences. The role of exposure time and postnatal timeline on the degree of cortical cell derangement remains a subject of controversy till date. This study therefore examines alcohol exposure and postnatal changes on brain weight, cortical neurons and astrocytes at different developmental periods. Methods: Twenty mature female Wistar rats were time-mated and grouped into 4 groups. Group 1 (control) received distilled water (2 mL/kg), Groups 2, 3 and 4 were administered 2.5 mL/kg of 20% ethanol orally on the 4th, 11th and 18th days of gestation respectively. Rats produced litters and pups' brains were harvested and processed for H&E and Golgi Cox stains at the 3rd and 6th postnatal week. Neuronal and astrocytic densities in the cerebral cortex were evaluated. Results and Conclusion: There was statistically significant increase (p<0.05) in the density of degenerating neurons at the third postnatal week and sixth postnatal weeks in the experimental groups when compared with the control. There was also statistically significant increase (p<0.05) in astrocytic density in groups 2 and 4 at the 3rd postnatal week. There was no statistically significant difference (p>0.05) in the astrocytic densities across groups at the sixth postnatal week. It was concluded that intrauterine alcohol exposure in any of the developmental periods resulted in postnatal neuronal degeneration which persisted till the 6th week. However, increased astrocytic densities is a feature of 1st and 3rd trimester alcohol exposure noted in the 3rd but absent in the 6th postnatal week.


Author(s):  
Ying-Ke Huang ◽  
Kai-Xing Lu ◽  
sha-sha li

Abstract Measuring the quasar distance through joint analysis of spectroastrometry (SA) and reverberation mapping (RM) observations is a new method for driving the development of cosmology. In this paper, we carry out detailed simulation and analysis to study the effect of four basic observational parameters (baseline length, exposure time, equivalent diameter and spectral resolution) on the data quality of differential phase curves (DPCs), furthermore on the accuracy of distance measurement. In our simulation, we adopt an axis symmetrical disc model of broad line region (BLR) to generate differential phase signals. We find that the differential phases and their Poisson errors could be amplified by extending the baseline, while the influence of OPD errors can be reduced during fitting the BLR model. Longer exposure time or larger equivalent diameter helps reduce the absolute Poisson error. Therefore, the relative error of DPCs could be reduce by increasing any of the above three parameters, then the the accuracy of distance measurement could be improved. In contrast, the uncertainty of $D_{\rm{A}}$ could be improved with higher spectral resolution, although the relative error of DPCs would be amplified. We show how the uncertainty of distance measurement varies with the relative error of DPCs. It is found that the relative error of DPCs $<$ 20$\%$ is a limit for accurate distance measurement. As any of the basic observational parameters become larger, the relative error of DPCs have a lower limit (roughly 5$\%$) and the uncertainty of distance measurement can be better than 2$\%$.


Toxins ◽  
2021 ◽  
Vol 14 (1) ◽  
pp. 21
Author(s):  
Zhiwei Chen ◽  
Fan Zhang ◽  
Lin Jiang ◽  
Zihan Chen ◽  
Hua Sun

Background: Fumonisin B1 (FB1) is one of the most common mycotoxins contaminating feed and food. Although regulatory limits about fumonisins have been established in some countries, it is still very important to conduct research on lower doses of FB1 to determine the tolerance limits. The aim of this study was to investigate the effects of different concentrations of FB1, provide further evidence about the toxic doses- and exposure time-associated influence of FB1 on mice, especially low levels of FB1 for long-term exposure. Methods: Female BALB/c mice were treated intragastrically (i.g.) with fumonisin B1 (FB1) solutions (0 mg/kg body weight (BW), 0.018 mg/kg BW, 0.054 mg/kg BW, 0.162 mg/kg BW, 0.486 mg/kg BW, 1.458 mg/kg BW and 4.374 mg/kg BW) once a day for 8 weeks to obtain dose- and time-dependent effects on body and organ weights, hematology, blood chemical parameters and liver and kidney histopathology. Results: After the long-term administration of FB1, the body weights of the mice tended to decrease. Over time, FB1 first increased the relative spleen weight, then increased the relative kidney weight, and finally increased the relative liver weight. The mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), hemoglobin (HGB), white blood cells (WBC), platelets (PLT), and mean platelet volume (MPV) were significantly elevated after treatment with FB1 for 8 weeks. Moreover, exposure time-dependent responses were found for aspartate aminotransferase (AST), alanine aminotransferase (ALT) and alkaline phosphatase (ALP) level, which were coupled with hepatic histopathological findings, necroinflammation and vacuolar degeneration and detrital necrosis. Linear dose response was also found for liver histopathology, in which, even the minimum dose of FB1 exposure also caused changes. Renal alterations were moderate compared to hepatic alterations. Conclusion: In conclusion, we demonstrated the systemic toxic effects of different doses of FB1 in female BALB/c mice at different times. Our data indicated that the effects observed in this study at the lowest dose tested are discussed in relation to the currently established provisional maximum tolerable daily intake (PMTDI) for fumonisins. This study suggested that recommendations for the concentration of FB1 in animals and humans are not sufficiently protective and that regulatory doses should be modified to better protect animal and human health. The toxicity of FB1 needs more attention.


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