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Exploring Recent (1991?2020) Trends of Essential Climate Variables in Greece
No full textEurope and the Mediterranean are considered climate change hot spots. This is the reason
why this paper focuses on the analysis of the trends of essential climate variables in a Mediterranean
country, Greece. The analyzed period is 1991?2020, and the dataset used is ERA5-Land (produced
by the European Center for Medium-Range Weather Forecasts), which has global coverage and
an improved resolution of ~9 9 km compared to other datasets. Significant climatic changes
across Greece have been put in evidence during the analyzed period. More specifically, the country
averaged a 30-year trend of temperature of +1.5 C, locally exceeding +2 C, and this increasing
trend is positively correlated with the distance of the areas from the coasts. Accordingly, the number
of frost days has decreased throughout the country. In terms of rainfall, a major part of Greece
has experienced increasing annual rainfall amounts, while 86% of the Greek area has experienced
a positive trend of days with heavy rainfall (>20 mm). Finally, a multiple signal of the trend of
consecutive dry days was found (statistically non-significant in the major part of Greece)
Effects of two typical quinolone antibiotics in the marine environment on Skeletonema costatum
No full textThis study investigated the effects of levofloxacin (LEV) and norfloxacin (NOR) on
Skeletonema costatum, focusing on cell growth, chlorophyll a (Chla) content,
maximal quantum yield of PSII (Fv/Fm), protein content, enzyme activities of
superoxide dismutase (SOD), glutathione reductase (GR), and glutathione
peroxidase (GSH-PX), and the membrane lipid peroxidation product
malondialdehyde (MDA) content were conducted to analyze the responses of S.
costatum under LEV and NOR exposure. Cell growth, Chla content, Fv/Fm, protein
content, enzyme activities, and MDA content were assessed to elucidate
physiological changes. Both LEV and NOR inhibited S. costatum growth, except for
10 mg/L NOR, which promoted growth. Algal cells exhibited higher sensitivity to LEV,
with 96h-IC50 values of 14.770 mg/L for LEV and 44.250 mg/L for NOR. Low NOR
concentration (10 mg/L) increased Chla content, while high antibiotic concentrations
(>20 mg/L for LEV, >100 mg/L for NOR) decreased Chla content and Fv/Fm,
indicating an impact on photosynthesis. Elevated LEV and NOR levels reduced
protein and MDA content but increased GR, SOD, and GSH activities, indicating
induced oxidative stress. The study provides a comprehensive analysis of LEV and
NOR effects on marine microalgae growth and underlying physiologicalmechanisms,
shedding light on potential ecological risks posed by antibiotics inmarine ecosystems
Biodiversity and Hemolytic Toxicity of the Genus Heterocapsa (Dinophyceae) in the Beibu Gulf, China
No full textThe dinoflagellate genus Heterocapsa includes several widely distributed and potentially
toxic species associated with Harmful Algal Blooms (HABs), particularly affecting theWestern Pacific
Ocean. To reveal the biodiversity of Heterocapsa in Beibu Gulf, six strains were morphologically
characterized using light and scanning electron microscopy, while large subunit rDNA (LSU rDNA)
and internal transcribed spacer (ITS) were sequenced for phylogenetic analysis through maximum
likelihood and Bayesian inferences. Two strains (BGERL169, BGERL170) were identified as Heterocapsa
philippinensis ribotype I, three (BGERL171-BGERL173) as a new Heterocapsa philippinensis ribotype
II, and one strain (BGERL174) as Heterocapsa pseudotriquetra. Cells of H. philippinensis were ovoid
to spherical, yellowish-brown, with reticulate chloroplasts, and had a sausage-shaped nucleus
positioned longitudinally along the dorsal side of the cell, and the theca was arranged in Po, cp, X, 5? ,
3a, 7?? , 6c, 5s, 5??? , 2???? . Additionally, BGERL169 and BGERL171 showed no hemolytic toxicity in rabbit
erythrocyte lysis assays. To the best of our knowledge, this research provides the first morphological
and phylogenetic analysis of H. philippinensis, including the identification of a new ribotype, as well
as the discovery of H. pseudotriquetra in Chinese waters. The findings contribute to the understanding
of Heterocapsa species biogeography and toxicity in Chinese waters, offering valuable data for future
HAB monitoring in Beibu Gulf
PENYERAPAN AIR, SIFAT MEKANIKAL DAN ANALISIS KECACATAN GENTIAN SEMULA JADI KOMPOSIT HIBRID BERTETULANG
No full textPROFIL FITOKIMIA, AKTIVITI ANTIBAKTERIA, DAN SITOTOKSISITI TUMBUHAN PANTAI TERPILIH MENENTANG BEBERAPA BAKTERIA PENYEBAB PENUMONIA
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AKTIVITI ANTIOKSIDAN DAN ANTIKULAT EKSTRAK DALAM DAUN Pereskia bleo DAN POTENSINYA SEBAGAI PENGAYAAN DALAM SALUTAN YANG BOLEH DIMAKAN UNTUK PENGAWETAN TOMATO
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