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Filter-based offline analysis of atmospheric aerosol hygroscopicity coupled to composition analysis provides information complementary to that obtained from online analysis. However, its application itself and comparison to online analysis have remained limited to date. In this study, daily submicrometer aerosol particles (PM0.95, 50 % cutoff diameter 0.95 µm) were collected onto quartz fiber filters on Okinawa Island, a receptor of East Asian outflow, in the autumn of 2015. The chemical composition of water-soluble matter (WSM) in PM0.95, PM0.95 itself, and their respective hygroscopicities were characterized through the offline use of an aerosol mass spectrometer and a hygroscopicity tandem differential mobility analyzer. Thereafter, results were compared with those obtained from online analyses. Sulfate dominated the WSM mass (59 %), followed by water-soluble organic matter (WSOM, 20 %) and ammonium (13 %). WSOM accounted for most (91 %) of the mass of extracted organic matter (EOM) and the atomic O-to-C ratios (O:C) of WSOM and EOM were high (mean ± standard deviation were 0.84 ± 0.08 and 0.78 ± 0.08, respectively), both of which indicate highly aged characteristics of the observed aerosol. The hygroscopic growth curves showed clear hysteresis for most samples. At 85 % relative humidity (RH), the calculated hygroscopicity parameter κ values of the WSM (κWSM), WSOM, EOM, and PM0.95 (κPM0.95) were 0.50 ± 0.03, 0.22 ± 0.12, 0.20 ± 0.11, and 0.47 ± 0.03, respectively. An analysis using the thermodynamic Extended Aerosol Inorganics Model (E-AIM) shows, on average, that inorganic salts and WSOM contributed 88 % and 12 %, respectively, of the κWSM (or κPM0.95). High similarities were found between offline and online analysis for chemical compositions that are related to particle hygroscopicity (the mass fractions and O:C of organics and the degree of neutralization) and also for aerosol hygroscopicity. As possible factors governing the variation in κWSM, the influences of WSOM abundance and the neutralization of inorganic salts were assessed. At high RH (70 %–90 %), the hygroscopicity of WSM and PM0.95 was affected considerably by the presence of organic components; at low RH (20 %–50 %), the degree of neutralization could be important. This study not only characterized aerosol hygroscopicity at the receptor site of East Asian outflow but also shows that offline hygroscopicity analysis is an appropriate method, at least for aerosols of the studied type. The results encourage further applications to other environments and to more in-depth hygroscopicity analysis, in particular for organic fractions.

Formation of biogenic secondary organic aerosol (BSOA) and its subsequent evolution can modify the hygroscopicity of the organic aerosol component (OA) in the forest atmosphere, and affect the concentrations of cloud condensation nuclei (CCN) there. In this study, size-resolved aerosol hygroscopic growth at 85 % relative humidity and size-resolved aerosol composition were measured using a hygroscopic tandem differential mobility analyzer and an aerosol mass spectrometer, respectively, at a forest site in Wakayama, Japan, in August and September 2015. The hygroscopicity parameter of OA (κorg) presented daily minima in the afternoon hours, and it also showed an increase with the increase in particle dry diameter. The magnitudes of the diurnal variations in κorg for particles with dry diameters of 100 and 300 nm were on average 0.091 and 0.096, respectively, and the difference in κorg between particles with dry diameters of 100 and 300 nm was on average 0.056. The relative contributions of the estimated fresh BSOA and regional OA to total OA could explain 40 % of the observed diurnal variations and size dependence of κorg. The hygroscopicity parameter of fresh BSOA was estimated to range from 0.089 to 0.12 for particles with dry diameters from 100 to 300 nm. Compared with the use of time- and size-resolved κorg, the use of time- and size-averaged κorg leads to under- and over-estimation of the fractional contribution of OA to CCN number concentrations in the range from −5.0 % to 26 %. This indicates that the diurnal variations and size dependence of κorg strongly affect the overall contribution of OA to CCN concentrations. The fractional contribution of fresh BSOA to CCN number concentrations could reach 0.28 during the period of intensive BSOA formation. The aging of the fresh BSOA, if it occurs, increases the estimated contribution of BSOA to CCN number concentrations by 52 %–84 %.

This paper introduces a methodology based on machine learning and remote sensing for detecting military-induced damages to agricultural lands in Ukraine using free Sentinel-2 satellite data. The most informative spectral bands (B2, B3) and vegetation indices (NDVI, GCI) were experimentally selected for recognizing damaged fields through the Random Forest classification algorithm. Additionally, an anomaly detection method based on the estimation of deviations of pixel values from the mean within each field was applied to determine local damage in the identified affected fields. The proposed methodology demonstrated high classification accuracy with an f1-score of 0.87%, producer’s accuracy of 0.89%, user’s accuracy of 0.85, and sensitivity for detecting local damage. The developed anomaly detection method allows to recognize damage visible on the 10-meter pixel of the Sentinel-2 satellite, but does not identify small craters. Cloudiness of satellite images can significantly impair the accuracy of damage detection, and the method of local damage detection can respond to non-military anomalies and requires careful selection of threshold coefficients for each field. The study conducted a comprehensive assessment of damages inflicted on Ukrainian agricultural fields during the period 2022-2023, revealing that a total of 1,544,952 hectares, equivalent to 5.72% of the total agricultural area, experienced damage. This included 509,107 ha of wheat, 114,302 ha of sunflower, 68,830 ha of maize, 4,029 ha of rapeseed, and 16,561 ha of other crops. The most affected regions were Donetsk, Zaporizhia, and Kherson oblasts. The comprehensive findings of this research provide valuable insights for monitoring the state of agriculture and formulating strategic plans for the recovery of agricultural resources amidst the ongoing military conflict.

Olive mill waste is low-quality feed and rarely used in ruminant nutrition because of its high lignocellulose content, the existence of anti-nutritional factors such as total polyphenol and condensed tannin, and low protein contents. This in vitro research was conducted to valorize this waste (crude olive cake, extracted olive cake, and olive leaves) using an exogenous fibrolytic enzyme produced from Trichoderma longibrachiatum in ruminal nutrition. The enzymatic activity of this additive was 1161 units of endoglucanase per millilitre, 113 units of exoglucanase per millilitre, and 2267 units of xylanases per millilitre. This treatment was applied by spraying substrates with four doses: 0 (control), 1 (low), 2 (medium), and 4µL g−1 µL g−1 (high) of dry matter olive mill waste in an air-conditioned room at 26 ∘C for 12 h before in vitro incubation. For the crude olive cake, this additive at high doses increased degradation of 14 % of cellulose and 8 % of hemicellulose compared with the control at 12 h before the in vitro incubation. Consequently, it increased dry matter solubility and reduced sugars at this period compared to the control. Upon ruminal incubation, the high dose of exogenous fibrolytic enzyme increased the gas production from the immediately soluble fraction and insoluble fraction, the rate of gas production for the insoluble fraction, the dry matter degradability by 26 %, the organic matter degradability by 24 %, the metabolizable energy value by 28 %, and the microbial crude protein production by 24 % compared with the control. For olive leaves, an exogenous fibrolytic enzyme at medium dosage can also hydrolyse the hemicellulose compound, release fewer sugars, and increase dry matter solubility compared with the control at 12 h before the in vitro incubation. Upon in vitro incubation, the medium dose increased the gas production from immediately soluble and insoluble fractions, the rate of gas production for the insoluble fraction, the dry matter degradability by 13 %, the organic matter degradability by 11 %, the metabolizable energy value by 12 %, and the microbial crude protein production by 12 % compared with the control. However, the highest dose altered the gas production from insoluble fractions and decreased microbial crude protein production by 6 % compared with the control. Under the same conditions, an exogenous fibrolytic enzyme applied to extracted olive cake did not produce any effect in the chemical composition and nutritional value. These results showed clearly that effectiveness of exogenous fibrolytic enzyme varied with incubated waste. Increasing the nutritional value of crude olive cake and olive leaves using an exogenous fibrolytic enzyme can encourage breeders to use this waste as feed at a low cost in animal nutrition. This valorization of waste is a good solution to reduce pollution of soils and groundwater caused by throwing out this polluted waste into the environment.

This study was conducted in order to assess the influence of four doses (0, 0.5, 1, and 2 mg (g dry matter)−1 of commercial fibrolytic enzymes (MAXFIBER-I®, SHAUMANN GmbH, Wahlstedt, Germany) on in vitro fermentation of date palm (Phoenix dactylifera) by-products: date kernels, wasted dates, floral stems, and palm fronds. Rumen contents were obtained from two non-lactating Holstein cows. Enzyme supplementation to by-products was carried out 12 h prior to incubation. Compared to the control, the enzymatic supplementation quadratically increased the extent but not the gas production rate of date kernel fermentation. Indeed, the potential gas production increased notably by 14.8 % with the lowest enzymes dose following recorded gas production after 48, 72, and 96 h of incubation. The estimated organic-matter digestibility, metabolisable energy, and total volatile fatty acids in the incubation fluid tended to be increased with the lowest dose by 7.8 %, 8.4 %, and 13.9 % respectively. For the wasted dates, this feed additive tended to linearly increase the gas production rate of fermentation with the highest dose. On the other hand, this supplementation had no effect on the ruminal fermentation of the floral stems and palm fronds. The exogenous fibrolytic enzymes were more effective on fibrous but not on lignified date palm by-products.

The axolotl, Ambystoma mexicanum, which has no specific calcium-containing sieve layer in the dermis, provides useful material for the study of the effect of Ca2+ on the development of amiloride-blockable active Na+ transport across the skin of amphibians. We raised axolotls in thyroid hormone or aldosterone or cultured the skin with corticoid plus one of several Ca2+ concentrations and found that 1) although the short-circuit current (SCC) was increased by both aldosterone and 3,3',5-triiodo-L-thyronine in vivo, only corticoid was necessary for such an increase in vitro; 2) the development of the SCC in vitro was both corticoid and Ca2+ dependent, because the SCC was well developed with over 100 microM Ca2+ but not with under 10 microM Ca2+ in the presence of corticoid, nor even with 300 microM Ca2+ without corticoid; and 3) Ca2+, but not corticoid, was necessary for the formation of cell-to-cell junctions, because the resistance of the skin was well developed with 300 microM Ca2+ without corticoid.

Amiloride-blockable Na(+) channels participate in active Na(+) transport across adult, but not larval, bullfrog skin. Their development is induced in vitro by culturing the tadpole skin with aldosterone. When tadpoles were raised in aldosterone (5 x 10(-7) M) for 2 weeks, however, neither development of such channels nor localization of antigen A, a marker of adult-type epidermis, was seen, the skin still being of the larval type. In contrast, aldosterone treatment did potentiate (by a factor of two) the activity of the acetylcholine receptor (ACh-receptor) channel, a functional marker of larval-type skin. The short-circuit current (SCC) across the skin, far from being inhibited by amiloride, was stimulated by both amiloride and ACh. The nystatin-stimulated SCC was about twice its control amplitude, suggesting that the aldosterone treatment also potentiated the activity of the Na(+) pump.

EDTA-treated larval bullfrog skin, in which apical and skein cells had been removed and only basal cells remained, was cultured in one of four media. These contained either aldosterone (Aldo) or a mixture of Aldo, hydrocortisone (HC) and corticosterone (C), each either supplemented with prolactin (PRL) or lacking PRL. Skin cultured with Aldo alone or with the corticoid mixture (Aldo + HC + C) developed an adult-type epidermis: (i) both types of skin reacted to human blood group antigen A, a marker for the adult-type epidermis of bullfrog skin; (ii) amiloride decreased the short-circuit current Isc in these skin preparations, but acetylcholine (ACh) had no effect on the Isc. It seemed to make little difference to the results whether the skin was cultured with Aldo or with the corticoid mixture. PRL antagonized the action of Aldo and induced the development of a larval-type epidermis in both skin preparations: (i) the skin preparations did not react to human blood group antigen A; (ii) acetylcholine and amiloride each stimulated Isc in these preparations. Since ACh and amiloride each stimulated the Isc in skin with apical cells, ACh/amiloride-stimulated channels may be located on these cells.

The response to acetylcholine (ACh) can be used as a marker for larval-type bullfrog skin because apically applied ACh induces an increase in short-circuit current (SCC) in larval-type but not adult-type skin. EDTA-treated larval skin, which contains only basal cells and does not respond to ACh, was used as the starting material for our culture. ACh, carbamylcholine, and choline stimulated SCC in skin that had been cultured with aldosterone (5 x 10(-7) M) supplemented with prolactin (PRL; 2 micrograms/ml). Atropine and d-tubocurarine each inhibited the ACh-induced stimulation of SCC in skin so cultured. Eserine, an inhibitor of acetylcholinesterase, also inhibited the ACh response. Amiloride stimulated SCC itself, but it reduced the ACh response. All of these results are quite similar to those seen in intact larval skin, suggesting that a larval-skin had differentiated from the basal cells used as the starting point for our culture. This is the first physiological report that PRL induces differentiation in vitro into a true larval-type bullfrog skin.

Active Na+ transport differentiates in larval bullfrog skin cultured with corticoids. After 2 wk in culture, the epidermis became positive against human blood group antigen A, the marker for the adult-type cells of the epidermis, but was negative to the antibody against the acetylcholine receptor, the marker for the larval-type epidermis. Amiloride (10(-5) M) did not inhibit the differentiation of active Na+ transport. On the other hand, in skin cultured with prolactin (2 micrograms/ml), the epidermis remained negative against antigen A and positive against acetylcholine receptor, and the differentiation of active Na+ transport was inhibited. Thyroid hormone did not antagonize the inhibitory action of prolactin on this transport differentiation. Prolactin affected the basal cells of the larval epidermis and inhibited development of corticoid-induced adult features in the epidermis.

The hormone-induced differentiation of an active Na+ transport across larval bullfrog skin during metamorphosis was investigated in vitro and in vivo. In in vitro experiments, EDTA-treated larval dorsal skin from which apical cells were removed was used. Even in the absence of thyroid hormone, corticoids induced the differentiation. Although aldosterone was the most potent hormone, hydrocortisone or corticosterone was also effective. Prolactin inhibited the corticoid-induced differentiation. The differentiation of the transport system coincided almost exactly with the appearance of adult features of the epidermis, namely, the epidermis at 7 days carried the human blood group antigen A, a specific molecular marker of adult-type bullfrog epidermis. The transport system appeared to develop in cells that had been newly generated from basal cells. On the contrary, in in vivo experiments, the effect of amiloride on the short-circuit current of the skin of tadpoles raised in the presence of aldosterone was very small, suggesting that a mechanism exists to inhibit the ability of aldosterone to induce the differentiation of the transport system in vivo.

Some molluscan ganglion cells were hyperpolarized by an excess of external K, contrary to expectations by the Nernst equation. The membrane resistance of the cells was markedly decreased with the hyperpolarization. This phenomenon was considered to represent a result of the summated IPSP's elicited by the presynaptic inhibitory fibers which were primarily depolarized by high K. We examined the effect of Cd in low pH saline on the membrane potential of snail ganglion cells in order to analyze this phenomenon further. Since Cd has been reported to block Ca channels, it might prevent neurotransmitter release from the presynaptic ending. In pH 8 control saline, the excess of K (22 mM) caused significant hyperpolarization and an evident decrease in membrane resistance, and these changes were not modified much after 1mM Cd addition. In pH 6.5 and 5 saline, the high K-induced hyperpolarization was markedly suppressed or even changed to depolarization by 1 mM Cd. The resistance change was also decreased in low pH Cd saline. Cadmium exerted a greater effect at rather higher concentrations. The results obtained suggest that the high K-induced hyperpolarization is due to the release of inhibitory neurotransmitter.

High K+-induced hyperpolarization was recorded intracellularly from the snail neurons, Euhadra subnimbosa, and the ionic mechanism underlying this hyperpolarization was analyzed in comparison with the ACh-induced hyperpolarization of the same cell, the latter known to be Cl(-)-dependent. The membrane resistance always decreased during both hyperpolarizing responses to high K+ (24mM) and ACh (0.1 mM). Both hyperpolarizing responses to high K+ and ACh were reversed in Cl(-)-free Ringer to the depolarizing responses. Both hyperpolarizing responses to high K+ and ACh were markedly augmented immediately after returning to normal Cl- from Cl(-)-free Ringer perfusion. Increase in intracellular Cl(-)-concentration by a leak from KCl-electrode reversed both hyperpolarizing responses to high K+ and ACh. Reversal potential of high K+-response was always 10-20 mV more positive than that of ACh-response, when measured in normal Ringer perfusion. Intracellular Cl(-)-concentration of the cells which were hyperpolarized by high K+ was estimated to be one half of that of the cells which were depolarized by high K+. Above results indicated that the high K+-induced hyperpolarization is due to the permeability increase of the postsynaptic membrane toward Cl-, masking the depolarizing effect of high K+ on the same membrane.

Two-thirds of the tested subesophageal ganglion cells of Japanese snail, Euhadra peliomphala, was hyperpolarized when they were perfused by high K-Ringer. This hyperpolarization was accompanied with a marked decrease in membrane resistance and was independent of cell types classified by ACh-induced response. Pentobarbital was found to convert high K-induced hyperpolarization into depolarization, or to augment K-depolarization. The high K-induced hyperpolarization was considered as the result of summated IPSP's elicited by the presynaptic inhibitory fibers which were primarily depolarized by high K. Pentobarbital may remove this synaptic inhibition and disclose the original K-depolarization underlying the cell. In Cl-free media, high K caused a marked depolarization instead of hyperpolarization, or augmented the depolarization observed in normal Ringer. This suggested that the subsynaptic membrane became permeable to Cl ions during the inhibitory presynaptic activity when high K was applied. ACh was found not to be responsible for this synaptic inhibition, because d-tubocurarine, which is known to block the Cl-dependent ACh response of the snail neurons, did not affect the high K-induced hyperpolarization. The possibility of indirect action of high K on the membrane potential through synaptically mediated inhibition was discussed as a cause of its hyperpolarizing effect.

Using the abdominal ganglion cells of Aplysia, we analyzed the effects of various enzymes and chemical modification reagents on the acetylcholine (ACh)-induced responses of the excitatory (Na+ -dependent) and inhibitory (Cl- -dependent) types. (1) Phospholipase A (2 mg/ml) caused no appreciable effects on either type of response. (2) Phospholipase C (2 mg/ml) markedly depressed both types of response. These suggested that the phosphoryl group of the phospholipid is an important site related to the binding of ACh, common to both types of ACh-receptors. (3) Carboxypeptidase A (10 mg/ml) caused no observable effects on either type of response. (4) Carboxypeptidase B (10 mg/ml) depressed the inhibitory type of response without affecting the excitatory one. (5) Pyridoxal-5'-phosphate (1 mM) also depressed the inhibitory response without affecting the excitatory one. These findings (4, 5) suggested that the Cl- -channel in the inhibitory ACh-receptor complex includes a C-terminal lysine which may play an active role in the movement of Cl- across the receptor membrane. (6) L-Leucine aminopeptidase (1 mg/ml) depressed the excitatory response without altering the inhibitory one. (7) p-Nitrothiophenol (1 mM)-also depressed the excitatory response without affecting the inhibitory one. These findings (6, 7) suggested the presence of a certain N-terminal amino acid near a glutamate or aspartate residue within a molecular moiety of Na+ -channel included in the excitatory ACh-receptor complex.

ACh-induced depolarization (D response) in D cells markedly decreases as the external Na(+) is reduced. However, when Na(+) is completely replaced with Mg(++), the D response remains unchanged. When Na(+) is replaced with Tris(hydroxymethyl)aminomethane, the D response completely disappears, except for a slight decrease in membrane resistance. ACh-induced hyperpolarization (H response) in H cells is markedly depressed as the external Cl(-) is reduced. Frequently, the reversal of the H response; i.e., depolarization, is observed during perfusion with Cl(-)-free media. In cells which show both D and H responses superimposed, it was possible to separate these responses from each other by perfusing the cells with either Na(+)-free or Cl(-)-free Ringer's solution. High [K(+)](0) often caused a marked hyperpolarization in either D or H cells. This is due to the primary effect of high [K(+)](0) on the presynaptic inhibitory fibers. The removal of this inhibitory afferent interference by applying Nembutal readily disclosed the predicted K(+) depolarization. In perfusates containing normal [Na(+)](0), the effects of Ca(++) and Mg(++) on the activities of postsynaptic membrane were minimal, supporting the current theory that the effects of these ions on the synaptic transmission are mainly presynaptic. The possible mechanism of the hyperpolarization produced by simultaneous perfusion with both high [K(+)](0) and ACh in certain H cells is explained quantitatively under the assumption that ACh induces exclusively an increase in Cl(-) permeability of the H membrane.