Search Results (10)

European hedgehogs are an important reservoir for many pathogens of health interest. Since hedgehogs live in close contact with humans, potential zoonotic fungi raise significant public health concerns, especially in areas with a high hedgehog density. From 2020 to 2023, 134 hedgehogs were surveyed for potential zoonotic fungi. Non-invasive methods were used, such as brushing live animals with a sterile toothbrush and taking oral and rectal swabs from deceased ones (86 animals). Dermatophytes were cultured on Dermasel agar and identified using molecular tools, while yeasts were isolated on Sabouraud agar with chloramphenicol and determined using Candida Chromogenic agar (MicroBiolDiagnostici^®, Cagliari, Italy) and MALDI-TOF (Microflex LT Smart Biotyper with FlexControlBiotyper 3.4 software, Bruker Daltonics, Bremen, Germany). Minimum inhibitory concentrations (MICs) were determined for Candida albicans isolates. Dermatophytes were found in just one hedgehog (0.8%, 95% C.I.: 0–0.04), identified as Paraphyton mirabile. Yeasts were detected in 22 of 86 hedgehogs (25.6%, 95% C.I.: 16.4–34.8), with 25 isolates obtained, including 21 Candida albicans, 2 Yarrowia lipolytica, 1 Rhodotorula mucilaginosa, and 1 Meyerozyma guilliermondii. All C. albicans isolates showed a high susceptibility to the antimycotic panel tested. Monitoring zoonotic fungi harbored by European hedgehogs, as well as raising public awareness on the topic, is of great importance for public health. Full article

Objectives. This study aimed to evaluate and compare the performance of different assays for antimicrobial susceptibility testing (AST) and minimum inhibitory concentration (MIC) determination for reserve antibiotics in carbapenem-resistant Enterobacterales (CREs), Pseudomonas aeruginosa (CRPAs), and Acinetobacter baumannii (CRABs). Methods. An analysis was conducted on 100 consecutive isolates: 50 CREs, 35 CRPAs, and 15 CRABs. Sensititre broth microdilution was used as a reference standard to evaluate the performance of VITEK 2 card AST-XN24 (bioMérieux), the respective gradient tests (bioMérieux), and UMIC colistin broth microdilution test strips (Bruker Daltonics). Errors, essential agreement (EA), and categorical agreement of MICs for colistin (COL), meropenem–vaborbactam (MVB), imipenem–relebactam (IRL), and eravacycline (ERV) were assessed. Results. The agreement between both of the COL broth microdilution (BMD) methods was perfect (100/100). The gradient test and VITEK 2 analysis yielded comparable EA rates (92/100 and 72/79, respectively), with the latter not registering any very major errors (VMEs). The MVB gradient test achieved EA in 66 of 85 isolates and VITEK 2 in 70/85. For IRL, EA was reached in 69 and 64 of 85 cases by gradient test and VITEK 2 analysis, respectively. The ERV gradient test yielded false results in nearly all (12/15) CRABs but achieved EA in 46 of 50 CREs. The VITEK system recorded EA for ERV in 60 of 65 isolates. Conclusions. We observed substantial variability in the measured MICs between BMD and the alternative methods. In only a few constellations, VITEK 2 or gradient tests could substitute the reference method. BMD is the method of choice for COL analysis, with VITEK 2 representing an alternative method for CRPA testing. Alternative methods for MVB did not provide reliable results, except for Enterobacterales, when tested with the gradient test. However, resistant results need to be confirmed by BMD. Only BMD can be used for IRL MIC determination. VITEK 2 was mostly accurate in measuring ERV MICs, while the corresponding gradient test yielded reliable results exclusively in CREs. It is essential that laboratories are aware of which testing method provides reliable results for each combination of microorganisms and reserve antibiotics. Full article

The objective of this paper is to reproduce and predict the series of solar cycle amplitudes using a simple time-series model that takes into account the variable time scale of the Gleissberg oscillation and the absence of clear evidence for odd–even alternation prior to Solar Cycle 9 (SC9). It is demonstrated that the Gleissberg oscillation can be quite satisfactorily modelled as a sinusoidal variation of constant amplitude with a period increasing linearly with time. Subtracting this model from the actual cycle amplitudes, a clear even–odd alternating pattern is discerned in the time series of the residuals since SC9. For this period of time, the mean value of the residuals for odd-numbered cycles is shown to exceed the value for even-numbered cycles by more than $4\sigma$, providing the clearest evidence yet for a persistent odd–even–odd alternation in cycle amplitudes. Random deviations from these means are less than half the standard deviation of the raw cycle amplitude time series for the same period, which allows the use of these regularities for solar cycle prediction with substantially better confidence than the simple climatological average. Predicted cycle amplitudes are found to be robust against the addition or omission of some data points from the input set, and the method correctly hindcasts SC23 and SC24. The potential physical background of the regularities is also discussed. Our predictions for the amplitudes of SC25, SC26, and SC27 are $155.8\pm 20.7$, $96.9\pm 25.1$ and $140.8\pm 20.7$, respectively. This suggests that the amplitude of SC26 will be even lower than that of SC24, making it the weakest cycle since the Dalton Minimum. Full article

(1) Background: In arid and semi-arid reservoirs, water surface evaporation is the main method of water dissipation in order to inhibit the evaporation of water and enhance economic efficiency. The evaporation inhibition rate of water-piled PV at different times of the year is derived from the anti-evaporation test of water-piled PV, and a new idea is proposed for water conservation in plains reservoirs in arid areas. (2) Methods: The test was conducted by dividing the area into groups A and B, with and without PV panel shading. In situ observation and numerical calculation were used to measure the atmosphere’s temperatures, test group, and PV module. The saturated water vapor pressure difference was then calculated according to Dalton’s principle to analyze the economic benefits of water saving. (3) Results: Based on the test results, it was found that the shading of PV panels had a cooling effect on the water body, the PV module, and the atmosphere. Group A showed a 44.2% decrease in the saturation water vapor pressure difference compared to Group B. The maximum evaporation suppression rate of 40.2% was observed in July, while the minimum rate of 12.2% was observed in January. The average evaporation suppression rate for the entire year was 29.2%. By utilizing the annual water savings for agricultural irrigation, it is possible to cover 38 hm² of land and generate a revenue of 39,000 CNY. (4) Conclusions: The photovoltaic water cover can effectively reduce water evaporation and generate economic benefits. Full article

Two Zn(II) coordination polymers, viz., [Zn₂Cl₂(H₂O)₂(µ-4-AmBz)₂]_n (1) and [ZnCl₂(µ-3-AmPy)₂]_n (2) (4-AmBz = 4-aminobenzoate, 3-AmPy = 3-aminopyridine) have been prepared at room temperature and characterized using elemental analysis, FT-IR, electronic spectroscopy, TGA (thermogravimetric analysis) and single crystal XRD. Crystal structure analyses of the polymers unfold the presence of non-covalent anion–π, π-stacking and unusual NH₂(amino)⋯π interactions which provide rigidity to the crystal structures. Unconventional Type I Cl⋯Cl interactions also play a pivotal role in the stability of compound 1. Molecular electrostatic potential (MEP) surface analysis reveals that the MEP values over the center of the aromatic rings of coordinated 4-AmBz and 3-AmPy moieties are positive on one side and negative on the other side which confirms the dual non-covalent donor-acceptor topologies of the aromatic rings and explains the concurrent formation of unusual non-covalent NH₂···π and anion–π interactions. DFT (density functional theory) calculations, QTAIM (quantum theory of atoms in molecules) and NCI plot (non-covalent index) index analyses reveal that among various non-covalent contacts involved in the crystal packing of the compounds, H-bonds in compound 1 and π-interactions (NH₂···π, π-π, anion–π) in compound 2 are energetically significant. We have explored in vitro cytotoxic potential of the compounds in Dalton’s lymphoma (DL) cancer cells using trypan blue and apoptosis assays. The studies show that compounds 1 and 2 can significantly exhibit cytotoxicity in DL cells with minimum cytotoxicity in healthy PBMC cells. Molecular docking studies reveal that the compounds effectively bind with the antiapoptotic target proteins; thereby establishing a structure activity relationship of the compounds. Full article

Based on newly-available meteorological reanalysis, we compile and present extended seasonal series of the North Atlantic Oscillation (NAO) and Greenland Blocking indices spanning 1800–2020, which we analyse for evidence of significant trends. This represents a major backward extension of the previously available instrumental-/reanalysis-based Azores–Iceland and principal component-based NAO indices, and allows us to evaluate the potential effect of natural climate perturbations, especially the 1809 and 1815 major volcanic eruptions and ~1790s–1830 Dalton solar minimum, on North Atlantic atmospheric circulation. We find that winters 1809/10 and 1816/17 mark positive NAO peaks, relative to several years before and afterwards, which is in accordance with the theory of volcanic forcing of climate. However, there is little evidence of a summer NAO volcanic signature. Overall, based on the significantly longer new reanalysis time series, the new series presented here corroborate and extend our previous results of: (1) a significantly more variable year-to-year NAO with a recent exceptional clustering of extreme events since 2000 for winter; (2) a significant increasing trend in blocking over Greenland in summer. These trends have major repercussions for the probability of the occurrence of extreme weather events over northwest Europe and for the sensitivity and response of the Greenland Ice Sheet to global warming, especially if they continue as an integral part of anthropogenic climate change. Full article

In this study, the results from the analysis of annual ring widths (‘Dm’) time series of two “very sensitive” to the climate and solar–climate relationships of long lived European beech (Fagus sylvatica) samples (on age of 209 ± 1 and 245 ± 5 years correspondingly) are discussed. Both series are characterized by very good expressed and relating to the solar magnetic Hale cycle 20–22-year oscillations. A good coincidence between the changes of ‘Dm’ and the growth or fading of the solar magnetic cycle is found. The transition effects at the beginning and ending of the grand Dalton (1793–1833) and Gleissberg minima (1898–1933) are very clearly visible in the annual tree ring width data for the one of beech samples. Some of these effects are also detected in the second sample. The problem for the possible “lost” sunspot cycle at the end of 18th century is also discussed. A prediction for a possible “phase catastrophe” during the future Zurich sunspot cycles 26 and 27 between 2035–2040 AD as well as for general precipitation upward and temperature fall tendencies in Central Bulgaria, more essential after 2030 AD, are brought forth. Full article

This work analyses new climate data on Southern Spain during the period 1792–1808. The data source is the periodical Correo Mercantil de España y sus Indias (Mercantile Mail of Spain and the Spanish Indies), which published weekly summaries of the weather conditions in Spain over this period. The study focuses on the southern provinces, providing 2788 new records, some of them corresponding to areas with no previously recorded data (Córdoba, Jaén). The analysis indicates the predominance of cold and dry winters, cold and wet springs, warm and dry summers, and variable autumn conditions, cold and humid in the western provinces while warm and dry in the eastern provinces. Some examples of these situations are discussed. Full article

The chemical and physical properties of extracellular rhamnolipid synthesized by a nonfluorescent Pseudomonas species soil isolate, identified as DYNA270, is described, along with characteristics of rhamnolipid production under varying growth conditions and substrates. The biosurfactant is determined to be an anionic, extracellular glycolipid consisting of two major components, the rhamnopyranoside β-1-3-hydroxydecanoyl-3-hydroxydecanoic acid (GU-6) and rhamnopyranosyl β→β2-rhamnopyranoside-β1-3-hydroxydecanoyl-3-hydroxydecanoic acid (GL-2), of molecular weight 504 and 649 daltons, respectively. These glycolipids are produced in a stoichiometric ratio of 1:3, respectively. The purified rhamnolipid mixture exhibits a critical micelle concentration of 20 mg/L, minimum surface (air/water interface) tension of 22 mN/m, and minimum interfacial tension values of 0.005 mN/m (against hexane). The pH optimum, critical micelle concentration, and effective alkane carbon number were established for Pseudomonas species DYNA270 and compared to those of rhamnolipid produced by Pseudomonas aeruginosa PG201. Significant differences are documented in the physical properties of extracellular rhamnolipids derived from these two microorganisms. The surface properties of this rhamnolipid are unique in that ultra-low surface and interfacial tension values are present in both purified rhamnolipid and culture broth containing the rhamnolipid complex (GU6 and GL2). We are not aware of prior studies reporting surface activity values this low for rhamnolipids. An exception is noted for an extracellular trehalose glycolipid produced by Rhodococcus species H13-A, which measured 0.00005 mN/m in the presence of the co-agent pentanol (Singer et al. 1990). Similar CMC values of 20 mg/L have been reported for rhamnolipids, a few being recorded as 5–10 mg/L for Pseudomonas species DSM2874 (Lang et al. 1984). Full article

Lake evaporation is a critical component of the hydrological cycle. Quantifying lake evaporation in hyper-arid regions by measurement and estimation can both provide reliable potential evaporation (ET₀) reference and promote a deeper understanding of the regional hydrological process and its response towards changing climate. We placed a floating E601 evaporation pan on East Juyan Lake, which is representative of arid regions’ terminal lakes, to measure daily evaporation and conducted simultaneous bankside synoptic observation during the growing season of 2013–2015. A semi-empirical evaporation model derived from Dalton model was parameterized and validated with measured data. The model was then used to estimate lake evaporation during 2002–2015. According to in situ measurements, maximum, minimum and mean lake evaporation were 8.1, 3.7 and 6.5 mm/day, and growing season evaporation was 1183.3 mm (~80% of the annual amount). Adding up non-growing season evaporation that we converted from φ20 pan evaporation at Ejina weather station, the annual mean lake evaporation, 1471.3 mm, was representative of lower Heihe River’s ET₀. Model inter-comparison implied our model performed well both in simplicity and accuracy and has potential utilization in a data-sparse area. In 2002–2015, estimated mean daily evaporation was 6.5 mm/day and growing season evaporation was 1233.7 mm. Trend analysis of estimated evaporation proved the evaporation paradox’s existence in this hyper-arid region and validated complementary relationship theory’s adaptability. Full article