69 research outputs found
The effects of calcite silicon-mediated particle film application on leaf temperature and grape composition of Merlot (Vitis vinifera L.) vines under different irrigation conditions
This study examined whether the application of calcite-silicon mediated particle film (CaPF) at veraison can mitigate a drought-induced increase in leaf temperature on grapevine, thus contributing to improved leaf functionality, yield and grape composition traits. A total of 48 five-year-old Merlot (Vitis vinifera L.) vines grafted onto SO4 were grown (in 20 L PVC pots) under Mediterranean conditions (Southern Italy). The vines were pruned to two spurs with two winter buds irrigated daily to 100 % field capacity, and fertilised weekly. At veraison and using a 2×2 factorial experimental design, the two main factors, thermoregulation and water, were imposed at two levels: spraying with a thermoregulation compound (CaPF) and no spraying (NS); irrigation (WW) and drought stress (D)). A group of 24 vines was subjected to a 15-day drought period by receiving, every day, 25 % (D) of the daily water consumption of WW vines. The other 24 vines continued to be fully irrigated on a daily basis (WW). Twelve vines per group were sprayed (WW+CaPF, D+CaPF) with calcite-silicon mediate (3 % V/V) at the beginning of drought imposition, the remaining 24 vines were not sprayed (WW-NS, D-NS). Soil water moisture and stem water potential values were monitored from 11.30 to 13:30 nearly every week, and other vegetative and reproductive parameters were also measured. During the experiment, air temperature peaked at ≈35 °C at midday, VPD at about 3.7 kPa and PAR reached ≈2000 µmol m-2 s–1. Results show that in CaPF sprayed vines, leaf-air temperature differences were lower than in unsprayed vines in both irrigated and drought stressed groups. WW+CaPF vines retained significantly more leaf area and showed the highest value of accumulated vine transpiration. Calcite-silicon mediated particle film could enhance the resilience of grapevine to adverse environmental conditions and may contribute to preserve terroir elements in highly reputed wine grape growing areas. The study showed that foliar application of calcite silicon-mediated processed particles films can be used in arid regions to mitigate leaf temperatures in grapevines
Edelfosine induced suicidal death of human erythrocytes
Background/Aims: The anti-inflammatory, anti-autoimmune, antiparasitic, and anti-viral ether phospholipid edelfosine (1-O-octadecyl-2-O-methylglycero-3-phosphocholine) stimulates apoptosis of tumor cells and is thus considered for the treatment of malignancy. Similar to apoptosis of nucleated cells, erythrocytes may enter eryptosis, the suicidal erythrocyte death characterized by cell shrinkage and phospholipid scrambling of the cell membrane with phosphatidylserine translocation to the erythrocyte surface. Triggers of eryptosis include Ca2+ entry with increase of cytosolic Ca2+ activity ([Ca2+]i) and oxidative stress. The present study explored, whether and how edelfosine induces eryptosis. Methods: Flow cytometry and photometry, respectively, were employed to estimate phosphatidylserine exposure at the cell surface from annexin-V-binding, cell volume from forward scatter, hemolysis from hemoglobin release, [Ca2+]i from Fluo3-fluorescence, and abundance of reactive oxygen species (ROS) from 2',7'-dichlorodihydrofluorescein diacetate (DCFDA) fluorescence. Results: A 6 hours exposure of human erythrocytes to edelfosine (5 \u3bcM) significantly increased the percentage of annexin-V-binding cells, significantly decreased forward scatter, and significantly increased Fluo3-fluorescence, but did not significantly modify DCFDA fluorescence. The effect of edelfosine on annexin-V-binding was significantly blunted, but not abolished by removal of extracellular Ca2+. Conclusions: Edelfosine triggers cell shrinkage and phospholipid scrambling of the erythrocyte cell membrane, an effect in part due to stimulation of Ca2+ entry
Nocodazole Induced Suicidal Death of Human Erythrocytes
Background: The microtubule assembly inhibitor nocodazole has been shown to trigger caspase-independent mitotic death and caspase dependent apoptosis. Similar to apoptosis of nucleated cells, erythrocytes may undergo eryptosis, the suicidal erythrocyte death characterized by cell shrinkage and cell membrane scrambling with phosphatidylserine translocation to the erythrocyte surface. Stimulators of eryptosis include increase of cytosolic Ca2+ activity ([Ca2+]i), oxidative stress and ceramide. The present study explored, whether and how nocodazole induces eryptosis. Methods: Flow cytometry was employed to determine phosphatidylserine exposure at the cell surface from annexin-V-binding, cell volume from forward scatter, [Ca2+]i from Fluo3-fluorescence, the abundance of reactive oxygen species (ROS) from 2\u2032,7\u2032-dichlorodihydrofluorescein (DCF) diacetate dependent fluorescence as well as ceramide surface abundance utilizing specific antibodies. Tubulin abundance was quantified by TubulinTracker\u2122 Green reagent and visualized by confocal microscopy. Results: A 48 hours exposure of human erythrocytes to nocodazole ( 65 30 \u3bcg/ml) significantly increased the percentage of annexin-V-binding cells without significantly modifying average forward scatter. Nocodazole significantly increased Fluo3-fluorescence, significantly increased DCF fluorescence and significantly increased ceramide surface abundance. The effect of nocodazole on annexin-V-binding was significantly blunted, but not abolished by removal of extracellular Ca2+ and was not modified in the presence of Caspase 3 inhibitor zVAD (1 \u3bcM). Nocodazole treatment reduced the content of total tubulin. Conclusions: Nocodazole triggers cell shrinkage and phospholipid scrambling of the erythrocyte cell membrane, an effect in part due to stimulation of Ca2+ entry, oxidative stress and ceramide
A dataset of acoustic measurements from soundscapes collected worldwide during the COVID-19 pandemic
Political responses to the COVID-19 pandemic led to changes in city soundscapes around the globe. From March to October 2020, a consortium of 261 contributors from 35 countries brought together by the Silent Cities project built a unique soundscape recordings collection to report on local acoustic changes in urban areas. We present this collection here, along with metadata including observational descriptions of the local areas from the contributors, open-source environmental data, open-source confinement levels and calculation of acoustic descriptors. We performed a technical validation of the dataset using statistical models run on a subset of manually annotated soundscapes. Results confirmed the large-scale usability of ecoacoustic indices and automatic sound event recognition in the Silent Cities soundscape collection. We expect this dataset to be useful for research in the multidisciplinary field of environmental sciences
The survival of the pentachlorophenol degrading Rhodococcus chlorophenolicus PCP-1 and Flavobacterium sp. in natural soil
The survival of two different pentachlorophenol (PCP)-degrading bacteria were studied in natural soil. The PCP-degraders Rhodococcus chlorophenolicus and Flavobacterium sp., both able to mineralize PCP into CO2 and chloride in axenic culture, were tested for the capacity to survive and degrade PCP in natural soil. These bacteria were immobilized on polyurethane (PUR) foam and introduced into natural peaty soil to give about 10(9) cells g(-1) of soil (dry weight). R. chlorophenolicus induced PCP-degrading activity in soil remained detectable for 200 days whether or not a carbon source was added (distillery waste or wood chips). Electron microscopic investigation performed almost a year after inoculation, revealed the presence of R. chlorophenolicus-like cells in the PUR foam particles. PCP-degrading activity of Flavobacterium sp. declined within 60 days of burial in the soil without enhancing the PCP removal. R. chlorophenolicus degraded PCP in soil at a mean rate of 3.7 mg of PCP day(-1) kg(-1) of soil, which corresponds to ca. 5 x 10(-3) pg of PCP degraded per inoculated R. chlorophenolicus cell day(-1). The solvent extractable organic chlorine contents of the soil decreased stoichiometrically (>95%) with that of PCP indicating that PCP was essentially mineralized
Use of electrical stimulation devices in strengthening the quadriceps femoral muscle
Transcutaneous muscular electrical stimulation is widely used as a valid aid in rehabilitation protocols after cruciate ligament reconstructive surgery and other situations characterised by muscular hypotrophy with a consequent loss of muscular strenght. From a review of the bibliography, no attention appears to have been focused on the question of whether transcutaneous electrical stimulation can prevent deterioration in muscular performance resulting from an interruption in athletic training. The aim of this study was to evaluate whether electrical stimulation can, augment muscular strenght in non-professional athletes during a five-week period in which the subjects enrolled in the study did not take any kind of physical exercise. The fourteen athletes who agreed to take part in this study used two of the most commonly used apparatus for electrical stimulation: the 'simplex' and the 'compex'. Each subject was randomly assigned to one of the two devices by drawing names. The following protocols were used; For the Compex: stimulation frequency (75 Hz); duration of tetanic contraction (4 sec); duration of decontraction (19 sec); decontraction frequency (4 Hz); total duration of training (18 min). For the Simplex: stimulation frequency (60 HZ); duration of tetanic contraction (7 sec); duration of decontraction (13 sec); total duration of training (20 min). The frequencies used for both training protocols were deemed to be capable of stimulating type II fibres (FT). All athletes were tested on two consecutive days before the start of the protocol and at the end of the five-week period using 'dyna biopsy' and an 'ergometer'. The results of this study show that the use of electrical stimulators can replace active training as a means of increasing muscle strenght, without any loss of strenght. On the contrary, a striking increase in muscle strenght was observed in some subjects who took part in this study
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