Fluorochrome Interaction with the Mitochondrial Membrane THE EFFECT OF ENERGY CONSERVATION

Abstract The interaction of 1-anilino-8-naphthalenesulfonate and 6-p-toluidino-2-naphthalenesulfonate with the membrane of both mitochondria and submitochondrial particles was studied. A fluorescence increase of the added fluorochromes was observed when energy was supplied to the membrane of submitochondrial particles, while a fluorescence decrease was observed with intact mitochondria. Binding studies and a comparison of the two fluorochromes have indicated that polarity changes of the membrane are not measured by 1-anilino-8-naphthalenesulfonate and 6-p-toluidino-2-naphthalenesulfonate. The fluorescence changes associated with energy conservation can be attributed to changes in the binding of the fluorochromes. Either a conformational change or a membrane potential change could account for the results

COMPARAZIONE DEL MANTELLO LITOSFERICO AFRICANO: STUDIO DEGLI XENOLITI DI MANTELLO DEI DISTRETTI VULCANICI DEL MAROCCO E DEL MAIN ETHIOPIAN RIFT

Two distinct mantle xenoliths series has been studied: one from the Azrou-Timahdite volcanic district, in the Middle Atlas (Morocco) and the other one from Mega in the Main Ethiopian Rift (MER), Sidamo region. The aim of the work is the characterization of the lithospheric mantle domains under the above mentioned areas and the comparison of these domains with other African volcanic provinces already studied; in the Saharan belt (Hoggar, Algeria and Gharyan, Lybia), and in the Ethiopian plateau (Injibara, Gojam and Dedessa, Wollega). Mantle xenoliths from the Pliocene-Quaternary volcanic diatremes of Azrou-Timadite area include spinel lherzolites xenoliths, 1 hazburgite and 1 olivin-websterite, with protogranular to porphyroclastic textures with superimposed metasomatic textures involving clinopyroxene, ortopyroxene and spinel as the main reacting phases. Olivine (ol) shows forsterite (Fo) between 88.7 in the lherzolites up to 91.8 in the harzburgite. Ortopyroxene (opx) composition varies with the following ranges: enstatite (En) 88.0 – 90.0, ferrosilite (Fs) 9.1 – 10.7 and wollastonite (Wo) 0.7 – 1.9. Clinopyroxene composition shows the following ranges: En 45.6 – 52.9, Fs 4.4 – 6.0 and Wo 41.3 – 49.0. Spinel is generally characterized by Mg# [Mg/(Mg+Fe)] between 72 – 84 and Cr# [Cr/(Cr+Fe)] between 6 – 32. Bulk rock trace elements, have flat Heavy Rare Earth Element (HREE) patterns (0.6 – 2.0 times chondrite) and are variably enriched in Light REE (LREE, with LaN/YbN between 1.1 and 15.6). The constituent clinopyroxenes are characterized by flat HREE distributions (3 – 10 times chondrite) and variable LREE enrichment with LaN/YbN from 0.1 to 23.7, which generally conform to the bulk rock chemistry. Sr-Nd-Pb isotope compositions of the cpx separates show the following compositional ranges: 87Sr/86Sr from 0.70243 to 0.70335, 143Nd/144Nd from 0.51273 to 0.51325, 206Pb/204Pb from 17.5 to 19.11, 207Pb/204Pb from 14.61 to 15.6 and 208Pb/204Pb from 36.34 to 39.08. Helium isotope determinations have been made on gases trapped in olivine and pyroxene from several xenoliths and show a narrow 3He/4He range between 6.2 – 6.8 Ra. On the whole these data indicate a lithospheric mantle that records a variable depletion by extraction of basic magma and subsequent metasomatic enrichments caused by interaction with alkali-silicate melts with a carbonatitic component. The isotope compositions show a prevalent HIMU metasomatic signature. Moreover, the relatively low 3He/4He isotopic rations suggest an origin within the upper mantle for this metasomatic agent. This situation is also recorded in other Northern African volcanic occurrences such as Hoggar (Algeria, Beccaluva et al., 2007) and Gharyan (Libya, Beccaluva et al., 2008), suggesting a common sublithospheric metasomatic agent across the area of the lithospheric mantle. Therefore, the volcanic district of the Saharan belt could have been related to small, second-order, “hot fingers” triggered by intraplate rifting related to tectonic reactivation of the Pan-African cratonic basement (Azzouni-Sekkal et al., 2007). This, in turn, may be considered a far-field foreland reaction to the Africa-Europe collisional system (Liégeois et al., 2005). Mantle xenolith from southern MER (Mega) consist of spinel lherzolites to harzburites, with 1 olivin-websterite, characterized by prevalent protogranular textures showing various degrees of deformation and re-crystallization with 120° triple boundaries. Microprobe data on the mineral phases show slight compositional difference between lherzolites and harzburgites. Olivine varies in composition between Fo 88.4 – 91.1 in lherzolites, 89.3 – 91.8 in harzurgites and 89.3 – 89.7 in the olivine-websterite. Orthopyroxene varies in the ranges: En 88.1 – 90.5, Fs 8.2 – 10.9, Wo 0.6 – 1.7 in lherzolites; En 89.3 – 91.5, Fs 7.6 – 9.5, Wo 0.9 – 1.4 in harzburgites and En 88.7 – 89.5, Fs 9.5 – 10.1, Wo 0.9 – 1.2 in the olivin-websterite. Clinopyroxene shows the following compositional variation: En 47.0 – 50.6, Fs 3.2 – 5.4, Wo 42.9 – 47.3 in lherzolites; En 48.4 – 52.1, Fs 3.0 – 5.4, Wo 42.9 – 47.2 in harzburgites and En 48.0 – 49.2, Fs 4.3 – 4.9, Wo 46.1 – 47.6 in the olivn-websterite. Spinel compositions in the lherzolites has Mg# between 72 – 83, in harzburgites between 60 – 79 and in the olivine-websterite between 81 – 83. The Cr# ranges between 8 – 58 in lherzolites, between 38 – 79 in harzburgites and between 38 – 40 in the olivin-websterite. The whole rock REE distribution show a flat HREE/Ch decreasing from 2.0 to 0.14 from lherzolites to harzburgites, compatible with a progressive depletion of the mantle material by extraction of basic melts. On the other hand, LREE/Ch shows variable enrichment most probably due to metasomatic processes, with LaN/YbN up to 41.5. Clinopyroxene shows a REE distribution generally parallel to those of the respective bulk rock with a flat HREE/Ch patterns (0.1 – 2.0 chondrite) and variously enrichments in LREE, with LaN/YbN ranging from 0.1 (in the fertile lherzolites) to 64.4 (in the most depleted harzburgites). Sr-Nd isotopic composition of clinopyroxene separated from Mega xenoliths range from 87Sr/86Sr 0.70220 – 0.70311, 143Nd/144Nd 0.51301 – 0.51379 for lherzolites, and 87Sr/86Sr 0.70268 – 0.70326, 143Nd/144Nd 0.51274 – 0.51305 for harzburgites, with the exception of harzburgite MA 29 that displays 87Sr/86Sr 0.70454, 143Nd/144Nd 0.51291. Lead isotopes display: 206Pb/204Pb 18.5 – 19.34, 207Pb/204Pb 15.53 – 15.63, 208Pb/204Pb 38.09 – 38.96 in lherzolites and 206Pb/204Pb 18.38 – 18.52, 207Pb/204Pb 15.21 – 15.67, 208Pb/204Pb 37.58 – 38.42 in harzburgites. The helium isotopic composition varies between R/Ra 7.1 to 8. The petrological and geochemical data on both rock and constituent minerals indicate that mantle xenoliths from Mega record a depletion by melt extraction events with superimposed metasomatic enrichments. The REE and trace elements patterns of MER xenoliths suggest alkali-silicate melt(s) as the main metasomatic agent(s) with carbonatitic component. The isotope data suggest for the metasomatism a fingerprinting approaching the HIMU endmember. The data carried out from this work suggest that the Mega xenoliths display close analogies with those from other areas along the Red Sea (Ottonello et al., 1978) and from the continental margin of the Aden’s Gulf (Baker et al., 1996). By contrast, mantle xenoliths from the northern Ethiopian plateau of Injibara and Dedessa show a distinct metasomatism due to sub-alkaline melts similar to the CFB magmas connected to the Afar Plume

Site-directed spin labeling of the mitochondrial membrane. Synthesis and utilization of the adenosine triphosphatase inhibitor (N-(2, 2, 6, 6-tetramethyl-piperidyl-1-oxyl)-N'-(cyclohexyl)-carbodiimide).

Abstract NCCD (N-(2,2,6,6-tetramethyl-piperidyl-1-oxyl)-N'-(cyclohexyl)carbodiimide) is a spin label inhibitor of ATPase of mitochondrial membrane fragments. Upon binding (∼0.5 nmole per mg of protein) its electron paramagnetic resonance spectrum becomes highly immobilized (τc = 2.10-8 s). The bound but not the free label is reduced by succinate, indicating that electrons can be transferred from the respiratory chain to the ATPase system. The Mn++ATP complex decreases the paramagnetic signal of NCCD bound to membrane fragments about 30%. Such an interaction can be the consequence of the vicinity of the binding sites of the two species

Photoelectrolytic oxidation of organic species at mesoporous tungsten trioxide film electrodes under visible light illumination

Operation of a photoelectrolyser fitted with a semitransparent semiconducting WO3 film photoanode is described. Due to its band-gap energy of 2.5eV, the photoresponse of the WO3 electrode extends into the blue part of the visible spectrum up to 500nm. The WO3 photoanode exhibits particularly high incident photon-to-current efficiencies for the oxidation of several organic species with the maximum occurring at ca. 400nm. Experiments conducted under simulated AM 1.5 solar illumination demonstrated efficient photodegradation of a variety of organic chemicals including small organic molecules as well as EDTA and anthraquinonic Acid Blue 80 dye. Although, due to the inherent mass transport limitations, the described device appears best suited to the treatment of industrial wastewater containing from 100ppm to few gL−1 of impurities, almost complete removal of organic carbon was observed in several photoelectrolysis runs. This is apparently associated with the concomitant photooxidation of sulphate-based supporting electrolyte resulting in the formation of a powerful chemical oxidant-persulphat

Elemental and isotopic profiling: a tool for distinguishing the botanical origin of oenological tannins

Much contemporary evidence underscores the pathophysiological importance of Ca2+ handling by acidic organelles such as lysosomes. Whereas our knowledge of how Ca2+ is released from these acidic Ca2+ stores (the ‘outs’) is advancing, we know relatively little about how Ca2+ uptake is effected (the ‘ins’). Here I highlight new work identifying animal Ca2+/H+ (CAX) exchangers that localize to acidic organelles, mediate Ca2+ uptake and regulate cell migration in vivo. Continued molecular definition of the acidic Ca2+ store toolkit provides new insight into Ca2+-dependent function

On Circuit Private, Multikey and Threshold Approximate Homomorphic Encryption

Homomorphic encryption for approximate arithmetic allows one to encrypt discretized real/complex numbers and evaluate arithmetic circuits over them. The first scheme, called CKKS, was introduced by Cheon et al. (Asiacrypt 2017) and gained tremendous attention. The enthusiasm for CKKS-type encryption stems from its potential to be used in inference or multiparty computation tasks that do not require an exact output. A desirable property for homomorphic encryption is circuit privacy, which requires that a ciphertext leaks no information on the computation performed to obtain it. Despite numerous improvements directed toward improving efficiency, the question of circuit privacy for approximate homomorphic encryption remains open. In this paper, we give the first formal study of circuit privacy for homomorphic encryption over approximate arithmetic. We introduce formal models that allow us to reason about circuit privacy. Then, we show that approximate homomorphic encryption can be made circuit private using tools from differential privacy with appropriately chosen parameters. In particular, we show that by applying an exponential (in the security parameter) Gaussian noise on the evaluated ciphertext, we remove useful information on the circuit from the ciphertext. Crucially, we show that the noise parameter is tight, and taking a lower one leads to an efficient adversary against such a system. We expand our definitions and analysis to the case of multikey and threshold homomorphic encryption for approximate arithmetic. Such schemes allow users to evaluate a function on their combined inputs and learn the output without leaking anything on the inputs. A special case of multikey and threshold encryption schemes defines a so-called partial decryption algorithm where each user publishes a ``masked\u27\u27 version of its secret key, allowing all users to decrypt a ciphertext. Similarly, in this case, we show that applying a proper differentially private mechanism gives us IND-CPA-style security where the adversary additionally gets as input the partial decryptions. This is the first security analysis of approximate homomorphic encryption schemes that consider the knowledge of partial decryptions. As part of our study, we scrutinize recent proposals for the definition and constructions of threshold homomorphic encryption schemes and show new random oracle uninstantiability results that may be of independent interest

An electrochemical study of natural and chemically controlled eumelanin

Eumelanin is the most common form of the pigment melanin in the human body, with functions including antioxidant behavior, metal chelation, and free radical scavenging. This biopigment is of interest for biologically derived batteries and supercapacitors. In this work, we characterized the voltammetric properties of chemically controlled eumelanins produced from 5,6-dihydroxyindole (DHI) and 5,6-dihydroxyindole-2-carboxylic acid (DHICA) building blocks, namely, DHI-melanin, DHICA-melanin, and natural eumelanin, extracted from the ink sac of cuttlefish, Sepia melanin. Eumelanin electrodes were studied for their cyclic voltammetric properties in acidic buffers including Na+, K+, NH4+, and Cu2+ ions

An electrochemical study on the effect of metal chelation and reactive oxygen species on a synthetic neuromelanin model

Neuromelanin is present in the cathecolaminergic neuron cells of the substantia nigra and locus coeruleus of the midbrain of primates. Neuromelanin plays a role in Parkinson's disease (PD). Literature reports that neuromelanin features, among others, antioxidant properties by metal ion chelation and free radical scavenging. The pigment has been reported to have prooxidant properties too, in certain experimental conditions. We propose an explorative electrochemical study of the effect of the presence of metal ions and reactive oxygen species (ROS) on the cyclic voltammograms of a synthetic model of neuromelanin. Our work improves the current understanding on experimental conditions where neuromelanin plays an antioxidant or prooxidant behavior, thus possibly contributing to shed light on factors promoting the appearance of PD

Comparing adaptive capacity index across scales: The case of Italy

Measuring adaptive capacity as a key component of vulnerability assessments has become one of the most challenging topics in the climate change adaptation context. Numerous approaches, methodologies and conceptualizations have been proposed for analyzing adaptive capacity at different scales. Indicator-based assessments are usually applied to assess and quantify the adaptive capacity for the use of policy makers. Nevertheless, they encompass various implications regarding scale specificity and the robustness issues embedded in the choice of indicators selection, normalization and aggregation methods. We describe an adaptive capacity index developed for Italy’s regional and sub-regional administrative levels, as a part of the National Climate Change Adaptation Plan, and that is further elaborated in this article. The index is built around four dimensions and ten indicators, analysed and processed by means of a principal component analysis and fuzzy logic techniques. As an innovative feature of our analysis, the sub-regional variability of the index feeds back into the regional level assessment. The results show that composite indices estimated at higher administrative or statistical levels neglect the inherent variability of performance at lower levels which may lead to suboptimal adaptation policies. By considering the intra-regional variability, different patterns of AC can be observed at regional level as a result of the aggregation choices. Trade-offs should be made explicit for choosing aggregators that reflects the intended degree of compensation. Multiple scale assessments using a range of aggregators with different compensability are preferable. Our results show that within-region variability can be better demonstrated by bottom-up aggregation methods.Measuring adaptive capacity as a key component of vulnerability assessments has become one of the most challenging topics in the climate change adaptation context. Numerous approaches, methodologies and conceptualizations have been proposed for analyzing adaptive capacity at different scales. Indicator-based assessments are usually applied to assess and quantify the adaptive capacity for the use of policy makers. Nevertheless, they encompass various implications regarding scale specificity and the robustness issues embedded in the choice of indicators selection, normalization and aggregation methods. We describe an adaptive capacity index developed for Italy's regional and sub-regional administrative levels, as a part of the National Climate Change Adaptation Plan, and that is further elaborated in this article. The index is built around four dimensions and ten indicators, analysed and processed by means of a principal component analysis and fuzzy logic techniques. As an innovative feature of our analysis, the sub-regional variability of the index feeds back into the regional level assessment. The results show that composite indices estimated at higher administrative or statistical levels neglect the inherent variability of performance at lower levels which may lead to suboptimal adaptation policies. By considering the intra-regional variability, different patterns of adaptive capacity can be observed at regional level as a result of the aggregation choices. Trade-offs should be made explicit for choosing aggregators that reflect the intended degree of compensation. Multiple scale assessments using a range of aggregators with different compensability are preferable. Our results show that within-region variability can be better demonstrated by bottom-up aggregation methods

Biodegradation of bio-sourced and synthetic organic electronic materials towards green organic electronics

Ubiquitous use of electronic devices has led to an unprecedented increase in related waste as well as the worldwide depletion of reserves of key chemical elements required in their manufacturing. The use of biodegradable and abundant organic (carbon-based) electronic materials can contribute to alleviate the environmental impact of the electronic industry. The pigment eumelanin is a bio-sourced candidate for environmentally benign (green) organic electronics. The biodegradation of eumelanin extracted from cuttlefish ink is studied both at 25 °C (mesophilic conditions) and 58 °C (thermophilic conditions) following ASTM D5338 and comparatively evaluated with the biodegradation of two synthetic organic electronic materials, namely copper (II) phthalocyanine (Cu–Pc) and polyphenylene sulfide (PPS). Eumelanin biodegradation reaches 4.1% (25 °C) in 97 days and 37% (58 °C) in 98 days, and residual material is found to be without phytotoxic effects. The two synthetic materials, Cu–Pc and PPS, do not biodegrade; Cu–Pc brings about the inhibition of microbial respiration in the compost. PPS appears to be potentially phytotoxic. Finally, some considerations regarding the biodegradation test as well as the disambiguation of “biodegradability” and “bioresorbability” are highlighted