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Abstract
In order to improve the thermal performance of heat exchangers and air collectors, we insert various forms of artificial roughness, known as ribs, into the useful duct. These ribs promote the creation of turbulent flows and enhance heat transfer by conduction, convection and radiation.
However, the introduction of these ribs leads to an increase in pressure drop, requiring higher mechanical power to pump the heat transfer fluid. This experimental study focuses on estimating, using empirical approaches, the pressure losses induced by rectangular ribs with an inclined top. The ribs are made from 0.4 mm galvanized sheet steel.
An experimental set-up was designed to measure the head losses generated by the ribs, from the point of entry to the point of exit from the useful duct. Using the dimensional analysis method, correlations were established to evaluate head losses as a function of flow regime and rib geometry and configuration (including different geometries for rib arrangement over the configuration area).
Abstract
We sought to determine the association between Toxoplasma gondii (T. gondii) infection of the central nervous system and suicide in a sample of decedents in Mexico City. One hundred and forty-seven decedents (87 who committed suicide and 60 who did not commit suicide) were studied. Brain tissues (amygdala and prefrontal cortex) of decedents were examined for the detection of T. gondii using immunohistochemistry. Detection of T. gondii was positive in 7 (8.0%) of the 87 cases (6 found in prefrontal cortex and one in amygdala), and in one (1.7%) of the 60 controls (found in prefrontal cortex) (OR: 5.16; 95% CI: 0.61–43.10; P = 0.14). Results suggest that T. gondii infection in brain is not associated with suicide. Further studies to confirm this finding are needed.
Banana is a cash crop in Mediterranean Region of Türkiye, which is grown mainly in greenhouses and open fields. In weed flora surveys carried out in 2021 and 2022, an Eastern Asian plant, Cardamine occulta Hornem. (Brassicaceae), was determined first time in 60% of banana greenhouses in Türkiye. The species had been recorded in Europe in the second half of the 20th century, and then spread especially in urban areas of many European countries and Mediterranean Basin, which implies many habitats in Türkiye under the threat of C. occulta. The main diagnostic morphological features and an identification key are presented in comparison with those for allied C. flexuosa With. and C. hirsuta L. An eradication program is suggested because it is not scattered but limited with banana greenhouses in Türkiye.
The epiphyllous liverwort collection was continued after the Covid pandemic in 2023 at the low and medium elevations of Batanta Island in the tropical rainforest belt by the entomolo-gist Tibor Kovács and his colleagues, which were identified by Tamás Pócs. The collection resulted in 35 species of which 9 liverworts proved to be new to Batanta Island along the species already known from the previous collections: Cheilolejeunea trapezia, Cheilolejeunea vittata, Cololejeunea schmidtii, Cololejeunea tenella, Colura herzogi, Drepanolejeunea cyclops, Leptolejeunea maculata, Microlejeunea punctiformis, and Radula javanica. Further three taxa are new even to science: Cololejeunea tiberii, Cololejeunea touwii subsp. batantae subsp. nov. and Drepanolejeunea levicornua var. incurviloba var. nov., which were described and illustrated by macro and microphotos. One previous identification was corrected. The results of 7 years of collecting activity resulting in 48 epiphyllous liverwort taxa known from Batanta Island are summarised.
New Records for the Liverwort and Hornwort Flora of Vietnam, 3
Epiphyllous collections of Pierre Tixier in the Natural History Museum, Paris
Pierre Tixier deposited a large amount of bryophyte collections, including epiphylls, in the Cryptogamic Herbarium of the Natural History Museum in Paris (PC). A very large part of his valuable epiphyllous specimens collected between 1957 and 1965 in the southern half of Vietnam remained unidentified. Based on study of a small portion of these collections, 44 species are reported including six new to the country (Dendroceros subplanus, Ceratolejeunea singapurensis, Cheilolejeunea rigidula, Cololejeunea angulata, C. stephanii and Thysananthus aculeatus). Ceratolejeunea and Dendroceros are genera new to Vietnam.
Abstract
The fungal genus Fusarium encompasses a diverse group of species responsible for synthesizing mycotoxins, particularly deoxynivalenol, fumonisin, and zearalenone and inducing Fusarium head blight in wheat. The research was undertaken over a period of two consecutive growing seasons (2020 and 2021) on the premises and facilities of the Hungarian University of Agriculture and Life Sciences (MATE). The objective of this study was to investigate the impact of growing season, nitrogen fertilization, and wheat variety on Fusarium infection as well as mycotoxin contamination in wheat kernel. Zearalenone was absent throughout the course of the two growing seasons, whereas deoxynivalenol was found solely in 2020. The findings demonstrate that nitrogen fertilization failed to exhibit a statistically significant impact on both Fusarium infection and mycotoxin production. The impact of wheat variety on Fusarium infection and deoxynivalenol was not found to be statistically significant. However, it exerted a significant effect on fumonisin production. The growing season exerted a statistically significant impact on the incidence of Fusarium infection and the ensuing contamination with mycotoxins, attributable to augmented precipitation levels in 2021 compared to 2020, specifically during the flowering period when the spike of wheat is highly susceptible to Fusarium infection.
Abstract
The acreage of English walnut (Juglans regia L.) is constantly expanding in Hungary, due to the favorable climatic conditions and economic importance. Last years, serious damage was reported from several orchards with high percentage of rotted, moldy kernels. The aim of this research was to identify the pathogens at different growth stages. Fungi were cultured from the spotty, shriveled and rotted kernels, and monosporic isolates were identified based on morphological characters and molecular markers (ITS region and tef1 locus sequences). Botryosphaeria dothidea and Diaporthe eres were identified in high proportion from symptomatic kernels. These species were also isolated from different parts of walnut trees in different seasons. D. eres was detected in a high proportion from asymptomatic buds in March, while the presence of both species was observed in symptomatic husks with Overnight Freezing-Incubation Technique (ONFIT) in June. Their optimal growth temperature defined to be between 20–25 °C, and the growth of D. eres isolates was completely inhibited at 35 °C.
Abstract
One of the major and yet unsolved threats for viticulture is the group of vascular fungal infections, the so-called grapevine trunk diseases. Besides their latent nature and the enormous number of associated pathogens, their control is also hampered by the lack of effective fungicides, directing growing attention toward the use of biocontrol agents. In the present study the isolation, identification, and characterization of a bacterial strain are presented, showing biocontrol potential against some main causal agents of grapevine trunk diseases. The strain was isolated from the wood of an asymptomatic grapevine and selected for the fungicidal activity against the pathogen Phaeomoniella chlamydospora. According to 16S rDNA, gyrA, and gyrB sequences, the isolate belongs to Bacillus velezensis species. Confrontation tests with the bacterium or with its fermentation broth further revealed growth inhibition and fungicide activity against Botryosphaeria dothidea, Eutypa lata and Diaporthe ampelina pathogens. Fractionation of the bacterial culture filtrate suggests that the antifungal agents secreted by the B. velezenzis isolate are mainly lipoproteins. Phytotoxicity tests were also carried out with the isolate, showing no harmful effects on grapevine foliar disks.
Abstract
Food industrial bacterial cells eliminate aflatoxin M1 (AFM1) at different ratios. The study aimed to investigate the effect of AFM1 on probiotic industrial bacteria (Lactococcus lactis ssp. lactis R703, Bifidobacterium animalis ssp. lactis BB12, and L. paracasei subsp. paracasei 431) and evaluating their AFM1 binding ability in naturally contaminated milk. The growth of the R703 strain was affected by AFM1 at 1.47 μg L−1 concentration. Peptidoglycan (PG) cell wall fractions of R703 and BB12 bound a significant amount of AFM1 from naturally contaminated milk under one-hour treatment, while L. paracasei 431 was not effective. PG was better absorbent for AFM1 than viable cells of BB12, while the difference was insignificant for the R703 strain. Increasing the time did not significantly change the mycotoxin binding of BB12, while for R703 PG the absorption seemed reversible. BB12 PG needs further analysis for biotechnological application in dairy products.
Abstract
This work used a carrageenan-based thrombosis model to determine the preventative effects of Lactobacillus plantarum YS1 (LPYS1) on thrombus. In thrombotic mice, LPYS1 improved the activated partial thromboplastin time (APTT), while decreasing the thrombin time (TT), prothrombin time (PT), and fibrinogen (FIB) content. In thrombotic mouse serum, LPYS1 decreased the levels of malondialdehyde (MDA), tumour necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), nuclear factor kappa-B (NF-κB), and interleukin-1 beta (IL-1β), while also increasing the activities of superoxide dismutase (SOD) and catalase (CAT). Moreover, LPYS1 upregulated the mRNA expression levels of copper/zinc-SOD (Cu/Zn-SOD), manganese-SOD (Mn-SOD), and CAT in the colon tissues of thrombotic mice, while downregulating those of NF-κB p65, IL-6, TNF-α, and interferon-gamma (IFN-γ) mRNA. In tail vein vascular tissues, LPYS1 suppressed the mRNA expression levels of NF-κB p65, intercellular cell adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and E-selectin. The abundances of both beneficial and pathogenic bacteria were altered by LPYS1. These findings show that LPYS1 has the capacity to protect mice from thrombosis, while also revealing some of the underlying mechanisms of this effect.
