Consuming Processes Research Articles

A ball milling-based one-step transformation of chitin biomass to organo-dispersible strong nanofibers passing highly time and energy consuming processes

Chitin, a sustainable and functional biological macromolecule, can be converted into chitin nanofibers (ChNFs), and are applicable as a mechanically reinforcing and bioactive filler for polymer matrices. Improving the performance of ChNFs typically relies on their nanofibrilization and miscibility with matrices. To transform chitin biomass into organo-dispersible ChNFs, a series of time-/energy-consuming chemical and mechanical treatments are required: 1) deacetylation, 2) disintegration, 3) surface modification to minimize their aggregation through hydrogen bonds, 4) drying, and 5) re-dispersion. This paper presents a one-step method to transform chitin biomass to organo-dispersible acetylated ChNFs via a ball-milling method in the presence of relatively low toxic acetic anhydride without water. This method minimizes water contaminations and energy for dehydrating. The resulting chitin nanofiber material is mixed with poly(l‑lactic acid) (PLLA) to produce all-bio-based nanocomposites. The composite indicated a 66% increase in Young's modulus and a 100% increase in tensile strength compared to the pristine PLLA. Furthermore, it did not exhibit any observable cytotoxic effect, thus potentially applicable as a biomedical material.

A Generalized Procedure for the Production of High-Grade, Porous Biogenic Silica

Biomasses are a sustainable, CO2 neutral source used in biorefining. Si-accumulating plants can be used for the production of biogenic silica in a biomass valorisation process. This study examines the production of high-grade porous silica from different plant parts like rice, oat and spelt husk, rice straw and horsetail using a generalized procedure for all. The silica materials were produced by a 2-step method. First, the biomasses were pretreated with water and then subjected to leaching with citric acid. As a second step, a sequential burning program was applied. The characterization of the untreated biomasses was carried out by X-ray fluorescence (XRF) analysis and thermal analysis (TG–DTA). The biogenic silica samples were subjected to XRF, carbon content analysis, low temperature nitrogen physisorption, scanning and transmission electron microscopy as well as X-ray diffraction. Independent of the initial composition of the plant part, the established method resulted in amorphous, biogenic silica with up to 99.7% purity, mesopores between 2 and 30 nm with pore volumes of up to 0.46 cm3 g−1 and specific surfaces of up to 303 m2 g−1. It was shown that the generalized method developed works not only for all the biomasses separately, but also if treated in the same batch. The produced biogenic silica can be considered as sustainable alternative to other silica products like precipitated silica, silica gel and fumed silica which are produced in highly energy consuming processes.

En route into chloroplasts: preproteins' way home.

Chloroplasts are the characteristic endosymbiotic organelles of plant cells which during the course of evolution lost most of their genetic information to the nucleus. Thus, they critically depend on the host cell for allocation of nearly their complete protein supply. This includes gene expression, translation, protein targeting, and transport-all of which need to be tightly regulated and perfectly coordinated to accommodate the cells' needs. To this end, multiple signaling pathways have been implemented that interchange information between the different cellular compartments. One of the most complex and energy consuming processes is the translocation of chloroplast-destined proteins into their target organelle. It is a concerted effort from chaperones, receptor proteins, channels, and regulatory elements to ensure correct targeting, efficient transport, and subsequent folding. Although we have discovered and learned a lot about protein import into chloroplasts in the last decades, there are still many open questions and debates about the roles of individual proteins as well as the mechanistic details. In this review, I will summarize and discuss the published data with a focus on the translocation complex in the chloroplast inner envelope membrane.

Metabolic Activity of the Liver during Exercise—A Metabolomics Approach

The liver plays a pivotal role in substrate metabolism during fasting and exercise. Chances in the hepatic uptake or release of metabolites regulate the hepatic energy supply for other organs. Here we evaluated substrate flow over the hepato-splanchnic bed by assessing arterial-to-venous differences based on UPLC and CE-MS metabolomics analysis at rest and during exercise. Catheterized healthy young male subjects (n = 10) performed 2 h of ergometer cycling followed by 4 h of recovery. In response to exercise there was pronounced hepatic uptake of lactate, pyruvate, various amino acids and dicarboxylic acids, indicating high demand for gluconeogenic substrates and increase in anaplerotic reactions of the citric acid cycle. Medium chain fatty acids e.g., caproic acid showed a clear hepatic uptake during exercise, underlining their potential role as regulators of gluconeogenesis and mitochondrial substrate oxidation. While most long chain fatty acids showed increased hepatic uptake, saturated fatty acids with carbon chain > 18 were released. In contrast to other amino acids, branched chain amino acids were not taken up or released from the liver at any time point. Notably, the hepato-splanchnic bed showed pronounced uptake of oxygen and release of CO2 during exercise indicating up-regulation of energy consuming metabolic processes. In conclusion, the data provide novel insight in the regulation of hepatic metabolism at rest and during exercise. Disclosure P. Plomgaard: None. C. Hu: None. J.S. Hansen: Employee; Self; Novo Nordisk A/S. X. Zhao: None. M. Hoene: None. X. Wang: None. N. Secher: None. H. Haering: None. R. Lehmann: None. G. Xu: None. C. Weigert: None.

Interfacial self-assembly of monolayer Mg-doped NiO honeycomb structured thin film with enhanced performance for gas sensing

The relatively low sensitivity, slow response and complicated or energy consuming preparation processes of NiO-based sensors greatly restrict their further application. In this work, monolayer Mg-doped NiO thin film was fabricated via an interfacial self-assemble strategy and a subsequent annealing process. Polystyrene spheres with diameters of about 700 nm were used as templates. The as-prepared monolayer Mg-doped NiO thin film presents a honeycomb structure. The film formation process and possible sensing mechanism of the honeycomb structured Mg-doped NiO thin film are also discussed. Moreover, the film-based gas sensor presents a high selectivity to ethanol gas against other gases. The response ratio of the Mg-doped NiO film sensor to 100 ppm ethanol is 10.4 at 325 °C. This ratio is also much better than some of the previously reported values in literatures. Furthermore, the Mg-doped NiO sensor also shows a significantly enhanced sensing properties in terms of higher selectivity, faster response and recovery time than our honeycomb structured pure NiO thin film. The remarkable properties may be attributed to the honeycomb structure and the Mg doping, which produce more active sites for the gas reaction and adsorption on the surface of the sensing materials. This facile fabrication strategy can be further utilized to prepare other monolayer metal oxide film-based devices.

Dynamic biochar effects on soil nitrous oxide emissions and underlying microbial processes during the maize growing season

Biochar application is a promising approach to decrease nitrous oxide (N2O) emissions from agricultural soils, yet little is known about how biochar affects N2O-producing and consuming microbial processes under changing field conditions. We conducted a field study to assess if growing season patterns in soil N2O emissions were correlated with the underlying microbial processes of nitrification and denitrification. We measured soil N2O emissions, potential nitrification and denitrification rates, and the abundance of key soil nitrogen (N)-cycling functional genes in an intensive maize production field trial in Illinois, USA that included the following four treatments: Control (unamended), Biochar (100 Mg ha−1), Nitrogen (269 kg N ha−1 as Urea Ammonium Nitrate fertilizer), and Biochar + Nitrogen (100 Mg ha−1 and 269 kg N ha−1, respectively). Biochar increased potential nitrification rates when soil ammonium concentrations were high following fertilizer application, thus enhancing N2O emissions in the Biochar + Nitrogen treatment early in the season which were likely nitrification-associated. However, over the full growing season, biochar application reduced cumulative N2O emissions in Biochar + Nitrogen plots to levels similar to the unamended Control. This could be attributed to biochar suppression of potential denitrification throughout the growing season. The treatments amended with biochar avoided large pulses of N2O emissions following intense rain events in the mid-season, while also sustaining lower N2O emissions in the late-season. Our study demonstrates that biochar can have dynamic effects on soil N2O emissions and the underlying microbial processes that depend on changing edaphic conditions, such as soil inorganic nitrogen availability and moisture, over the growing season.

Renal oncocytoma characterized by the defective complex I of the respiratory chain boosts the synthesis of the ROS scavenger glutathione.

Renal oncocytomas are rare benign tumors of the kidney and characterized by a deficient complex I (CI) enzyme activity of the oxidative phosphorylation (OXPHOS) system caused by mitochondrial DNA (mtDNA) mutations. Yet, little is known about the underlying molecular mechanisms and alterations of metabolic pathways in this tumor. We compared renal oncocytomas with adjacent matched normal kidney tissues on a global scale by multi-omics approaches, including whole exome sequencing (WES), proteomics, metabolomics, and metabolic pathway simulation. The abundance of proteins localized to mitochondria increased more than 2-fold, the only exception was a strong decrease in the abundance for CI subunits that revealed several pathogenic heteroplasmic mtDNA mutations by WES. We also observed renal oncocytomas to dysregulate main metabolic pathways, shunting away from gluconeogenesis and lipid metabolism. Nevertheless, the abundance of energy carrier molecules such as NAD+, NADH, NADP, ATP, and ADP were significantly higher in renal oncocytomas. Finally, a substantial 5000-fold increase of the reactive oxygen species scavenger glutathione can be regarded as a new hallmark of renal oncocytoma. Our findings demonstrate that renal oncocytomas undergo a metabolic switch to eliminate ATP consuming processes to ensure a sufficient energy supply for the tumor.

Assessing the applicability of OpenStreetMap data to assist the validation of land use/land cover maps

ABSTRACTThe validation of land use/land cover (LULC) maps is usually performed using a reference database consisting of a sample of points or regions to which the ‘real’ class is assigned. This assignment is usually performed by specialists using photointerpretation (PI) of high-resolution imagery and/or field visits, which are time consuming and expensive processes. The aim of this article is to assess if the data available in the collaborative project OpenStreetMap (OSM) may be used as a source of data to assist the creation of these reference databases, reducing the time spent and costs associated with their generation. For this aim, two case studies were used, where the validation of the Global Monitoring for Environment and Security Urban Atlas (UA) was performed. The used methodology requires the harmonization of the data available in OSM with the UA nomenclature, and the subsequent creation of a LULC map from the OSM data. This map was then compared to UA to assess the similarity of the regions mapped in both. To test the usefulness of OSM data to assess the accuracy of UA, a sample of points was created and two reference databases generated, one assigning the data extracted automatically from OSM to the points where these data were available, and PI for the remaining points, and the other using only PI. The accuracy assessment of UA for the two case studies was then made building confusion matrixes and computing accuracy indicators. The results showed that for the two study areas, only low percentages of points had to be photo interpreted in the first reference database (respectively, 12% and 2% for the two study areas), decreasing the work load considerably. The results obtained with both reference databases are comparable for level 1 classes. For level 2 classes, worse results were obtained for some classes, showing that the OSM data used are not enough to create reliable reference data.

The biogeochemistry of gas generation from low-level nuclear waste: Modelling after 18 years study under in situ conditions

Gas generation from low- and intermediate-level nuclear waste (LILW) is an important process related to the safety of near surface and geological nuclear waste repositories. Generation of a gas phase has the potential to transport gaseous radionuclides such as 14C to the biosphere. Furthermore, pressurisation and gas phase formation can affect the engineered barrier system and water flow, which can affect the transport of radionuclides and other soluble contaminants in water. Microbial gas generation is coupled with a wider range of biogeochemical processes that are also relevant to the safety of LILW repositories through effects on pH, Eh and organic complexation. The large scale Gas Generation Experiment (GGE), located at the VLJ repository, Olkiluoto, Finland has been in operation for 18 years to study processes of gas generation from cellulose-containing low-level waste (LLW) from the Olkiluoto power plants. Here we provide an update of the experiment data set that records, over a period of 18 years, the neutralisation of the initial pH 10–11 conditions in the water filled regions of the experiment that were buffered by a concrete container, of relatively small mass, by acidity generated by degradation of cellulose LLW materials. The neutralisation of pH below pH 9 coincides with a doubling of the generation rate of a CH4-rich gas to around 1 m3 per year. Aqueous sulfide is also present at low levels (<3 × 10−6 M) at this time, consistent with equilibrium with mackinawite (FeS). Dissolved organic carbon attained a peak concentration of 8 mM during the early stages of the experiment, prior to the higher gas generation rate, but after 9 years declined. After 18 years the Eh of the tank water measured by a Pt electrode is consistent with that calculated for the S(-2)/S(6) and methanogenesis redox couples suggesting equilibration of redox processes. Carbonate concentration has increased steadily to around 15 mM. After 7 years CO2 gas and aqueous and solid carbonates are also close to equilibrium. The experimental data has been interpreted with the aid of a biogeochemical model that represents the coupled processes of organic waste degradation, pH buffering and microbial gas generation. The model simulates that the majority of the gas is generated by H2 and organic consuming methanogenic processes in the waste drums. The increase in CH4 generation is simulated to be the result of methanogenic processes that consume soluble cellulose degradation products that diffuse into the tank water from the waste drums. It is expected that under the steady state conditions now established, resulting from gas/liquid/solid equilibrium and diffusion processes, that gas generation should continue until the cellulose and steel materials are exhausted. The experimental data and biogeochemical model can be used to predict the rate of CH4-rich gas generation from the VLJ and other repositories with higher proportions of cementitious materials. In addition the study has shed further light on the role of microbial processes in affecting pH buffering of cementitious conditioned LILW.

Biological Activity of Persian Sturgeon Recombinant Growth Hormone Molecules Trapped In Inclusion Bodies (IBs)

The biological activity of Persian sturgeon (PS) enfolded crude recombinant growth hormone (rGH) recovered from inclusion bodies (IB) estimated by administrating to fish fingerlings. The psrGH IBs expressed in E. coli were dissolved in cold guanidine HCl solution, immediately diluted ~1000 fold in cold sodium chloride 0.9% solution do not allow the rGH folding and administrated to fishes. It was revealed that intramuscularly injections of rGH at dosage of 0.5 μg/ g once a week for 8 weeks significantly accelerate the growth of fishes. Comparison of the mean growth rate and daily weight and length gain dates of Persian sturgeon fingerlings administrated by pure and crude grade rGH revealed the existence at list 2-5% potentially biologically active psrGH molecules in IBs. This fact enables to avoid the time and cost consuming processes of refolding and purification of rGHs.

Non-iterative Pseudo Inverse Based Recovery Algorithm (NIPIRA) for Compressively Sensed Images and Videos

Recent development in data compression emphasizes compressed sensing technique as a widely applied one for compression and reconstruction of images and videos by projecting the pixel values into smaller dimensional measurements. These compressed measurements are reconstructed at the receiver using suitable reconstruction algorithms, generally the greedy algorithms. Greedy algorithms are time consuming and complex processes, giving rise to a trade-off between reconstruction performance and algorithmic performance. This work proposes a non-iterative method, non-iterative pseudo inverse based recovery algorithm (NIPIRA), for reconstruction of compressively sensed images and videos that exhibits small complexity and time requirement along with preservation of reconstruction quality. Mathematical proofs for NIPIRA’s accuracy and optimality provide additional theoretical support to the algorithm. NIPIRA gives a minimum PSNR of 32 dB for very few measurements, accuracy of above 97 and 92% decrease in elapsed time compared with other iterative algorithms. The complexity of NIPIRA is \(O(MN)\) which is \(s\) times less than OMP and StOMP.

Cold Stress and Nitrogen Deficiency Affected Protein Expression of Psychrotrophic Dyadobacter psychrophilus B2 and Pseudomonas jessenii MP1.

Nitrogen (N) deficiency and low temperature conditions are the prominent facet of Western Himalayan agro-ecosystems. A slight change in the environment alters the protein expression of the microorganisms. Therefore, proteomes of the two psychrotrophs Dyadobacter psychrophilus B2 and Pseudomonas jessenii MP1 were analyzed using two dimensional electrophoresis and MALDI–TOF–MS, to determine the physiological response of altitudinally different but indigenous microorganisms in response to cold stress under N depleting conditions. Functional assessment of 150 differentially expressed proteins from both the psychrotrophs revealed several mechanisms might be involved in cold stress adaptation, protein synthesis/modifications, energy metabolism, cell growth/maintenance, etc. In both the proteomes, abundance of the proteins related to energy production and stress were significantly increased while, proteins related to biosynthesis and energy consuming processes decreased. ATP synthase subunit alpha, beta, ATP-dependent Clp protease, Enolase, groL HtpG and N(2)-fixation sustaining protein CowN proteins were found to be expressed in both B2 and MP1, similarly to previously studied diazotrophs under low temperature N2 fixing conditions and therefore, can be considered as a biomarker for monitoring the nitrogen fixation in cold niches. Nevertheless, in both the diazotrophs, a good fraction of the proteins were related to hypothetical proteins which are still uncharacterized, thereby, suggesting the need for in-depth studies on cold adapted diazotrophs and their adaptive mechanisms.

Continuous synthesis of UiO-66 in microreactor: Pursuing the optimum between intensified production and structural properties

The increasing demand for MOFs can only be satisfied by establishing robust and reproducible synthesis routes which allow a profitable scale-up of the requested materials while preserving their textural properties and stability. A scalable MOF synthesis may provide a technology platform for the further development and modification of the product, from both a chemical and an engineering perspective. And, above all, MOFs could be delivered to the market at a substantially reduced price.In this work UiO-66 was synthesized continuously by employing micro reactors and the concept of flow chemistry. The microreaction technology (MRT) process turned out to be a viable alternative to the time and energy consuming conventional synthesis processes, as significantly faster reaction rates could be achieved compared to the conventional batch processes (Zhou et al., 2014; Frameworks for Commercial Success, 2016). Microreactors are characterized in particular by high surface-to-volume ratios and channel dimensions in the submillimeter range, which offer a significant enhancement of heat and mass transfer within the reactor, additionally the chemical reactions can be accelerated by orders of magnitude and can thus be processed close to their kinetic optimum conditions.Different reaction parameters were studied in order to elucidate their influence on the product properties. All synthesized MOF crystals were characterized by X-ray diffraction, scanning electron microscopy, thermogravimetric analysis and nitrogen adsorption measurements.The MRT approach allowed the continuous fabrication of MOF crystals with distinct morphological characteristics in a time-efficient manner. The obtained results represent a faster and energy-efficient route to continuously produce UiO-66, compared to the standard synthetic protocols. The materials prepared in this work have a lower coordination of the Zr sites in comparison to the UiO-66 that can be produced in batch (Cavka et al. 2008); nevertheless the presence of coordinative unsaturated sites is a preferred feature of MOFs for some specific application such as catalysis (Shearer et al., 2014).

Optimization of Yield for Extraction of an Essential Oil from Cinnamon Using Microwave-Assisted Extraction

Essential oil is concentrated hydrophobic liquid which containing volatile aromatic compounds extracted from flowers, leaves, stems, roots, seeds, barks, resins, or fruit rinds. These oils are often used for their flavor and their therapeutic or odoriferous properties, in a wide selection of products such as foods, medicines, and cosmetics. Extraction of essential oils is one of the most time and effort consuming processes. Cinnamon is an important herbal medicine with good effects of health promotion and disease prevention. In this work, the volatile compounds of cinnamon bark were extracted by Hydrodistillation and Microwave-assisted extraction (MAE) techniques. Gas chromatography/mass spectrometry was used to identify and quantify the volatile compound composition. The results indicated that cinnamaldehyde was the major component with the highest % area of 89.324% in the volatile oils extracted by MAE while in hydrodistillation method cinnamaldehyde was about 68%. MAE has been recognized as a technique with several advantages over other extraction methods, such as reduction of costs, extraction time, energy consumption, and CO2 emissions. MAE technique is a green technique which is highlighted by increased extraction yield, decreased time and solvent consumption, moreover the reproducibility is better. For this purpose, various process parameters such as solid loading, water volume, microwave power and extraction time were studied in detail and optimized using the Taguchi method and Artificial neural network. The optimized extraction conditions were obtained at, solid loading of 30 g, water volume of 250 ml, microwave power of 700 W and extraction time of 25 min. Under optimized conditions, 4.169% (w/w) yield of essential oil was obtained.

Numerical investigations in structures with imperfect material interfaces and cracks

AbstractNatural fiber reinforced bio‐polymers are in the focus of many research projects to understand and improve the mechanical behavior subjected to different process parameters during production. To provide safe and reliable light weight constructions, special interest is directed towards the damage and fracture behavior of such composite materials. Here, the material's behavior at the imperfect material interface between fiber and matrix plays an essential role and governs inelastic effects at the interfaces on the one hand, and the behavior of growing cracks on the other. The reduction of the elastic potential is related to both energy consuming processes in the system and in general is going along with a reduction of the crack tip loading and a shift of the crack growth direction. In this paper, the crack tip loading analysis in structures with perfect and imperfect material interfaces is presented and applied to different specimens. (© 2016 Wiley‐VCH Verlag GmbH &amp; Co. KGaA, Weinheim)

Synthesis of Metal Oxide Precursors for the Generation of Oxides or Similar Nanomaterials for Na-Ion Battery Cathode Production

The current growing need of energy storage is an issue that can be solved at least partially by electrochemical storage, like batteries. Nowadays, most of the Li-ion battery cathodes are made of lithium cobalt oxide, LiCoO2, prepared by highly energy consuming solid state processes, involving solid state method at high temperature and for long reaction times (600-900°C, 36hours [1]). Aurelien Crochet and Jean-Pierre Brog of the Fromm group developed a way of producing the high-temperature phase of LiCoO2 (HT-LiCoO2) [2] at low temperature using heterometallic Li-Co alkoxides complexes as molecular precursors, following the general equation below. [Li2Co(OR)4(L)4] → HT-LiCoO2 + Li2CO3 + CO2 + H2O Despite lower performances, Na-ion batteries are good candidates in an effort to produce cheaper and more environmentally friendly batteries compared to Li-ion batteries. Complexes of [NaxMy(OR)z(L)a], where M is a transition metal, OR an alkyl or aryl oxide group and L a ligand, can be synthesized in analogy to the lithium precursors in order to use them for the generation of sodium metal oxides. Those oxides will be characterized and tested as cathode materials. We will present our first efforts and results on this kind of synthesis.

Evaluation of energy metabolism and calcium homeostasis in cells affected by Shwachman-Diamond syndrome.

Isomorphic mutation of the SBDS gene causes Shwachman-Diamond syndrome (SDS). SDS is a rare genetic bone marrow failure and cancer predisposition syndrome. SDS cells have ribosome biogenesis and their protein synthesis altered, which are two high-energy consuming cellular processes. The reported changes in reactive oxygen species production, endoplasmic reticulum stress response and reduced mitochondrial functionality suggest an energy production defect in SDS cells. In our work, we have demonstrated that SDS cells display a Complex IV activity impairment, which causes an oxidative phosphorylation metabolism defect, with a consequent decrease in ATP production. These data were confirmed by an increased glycolytic rate, which compensated for the energetic stress. Moreover, the signalling pathways involved in glycolysis activation also appeared more activated; i.e. we reported AMP-activated protein kinase hyper-phosphorylation. Notably, we also observed an increase in a mammalian target of rapamycin phosphorylation and high intracellular calcium concentration levels ([Ca2+]i), which probably represent new biochemical equilibrium modulation in SDS cells. Finally, the SDS cell response to leucine (Leu) was investigated, suggesting its possible use as a therapeutic adjuvant to be tested in clinical trials.

The sensitivity of water chemistry to climate in a forested, nitrogen-saturated catchment recovering from acidification

Fluxes of major ions and nutrients were measured in the N-saturated mountain forest catchment-lake system of Čertovo Lake (Czech Republic) from 1998 to 2014. The lake has been rapidly recovering from atmospheric acidification due to a 90% decrease in sulphate (SO42−) deposition since the late 1980s and nitrate (NO3−) contribution to the pool of strong acid anion and leaching of dissolved organic carbon (DOC) have increased. Present concentrations of base cations, phosphorus (P), total organic N (TON), and ionic (Ali) and organically bound (Alo) aluminium in tributaries are thus predominantly governed by NO3− and DOC leaching. Despite a continuing recovery lasting 25 years, the Čertovo catchment is still a net source of protons (H+), producing 44mmolm−2yr−1 H+ on a catchment-area basis (corresponding to 35μmolL−1 on a concentration basis). Retention of the deposited inorganic N in the catchment averages 20%, and ammonium consumption (51mmolm−2yr−1) and net NO3− production (28molm−2yr−1) are together the dominant terrestrial H+ generating processes. In contrast, the importance of SO42− release from the soils on terrestrial H+ production is continuously decreasing, with an average of 47mmolm−2yr−1 during the study. The in-lake biogeochemical processes reduce the incoming acidity by ∼40%, neutralizing 23μmolL−1 H+ (i.e., 225mmolm−2yr−1 on a lake-area basis). Denitrification and photochemical and microbial decomposition of DOC are the most important in-lake H+ consuming processes (50 and 39%, respectively), while hydrolysis of Ali (from tributaries and photochemically liberated from Alo) is the dominant in-lake H+ generating process. Because the trends in water chemistry and H+ balance in the catchment-lake system are increasingly related to variability in NO3− and DOC leaching, they have become sensitive to climate-related factors (drought, elevated runoff) and forest damage that significantly modify the leaching of these anions. During the study period, increased exports of NO3− (accompanied by Ali and base cations) from the Čertovo catchment occurred after a dry and hot summer, after forest damage, and during elevated winter runoff. Increasing DOC export due to decreasing acid deposition was further elevated during years with higher runoff (and especially during events with lateral flow), and was accompanied by P, TON, and Alo leaching. The climate-related processes, which originally “only” confounded chemical trends in waters recovering from acidification, may soon become the dominant variables controlling water composition in N-saturated catchments.

Shwachman-Diamond Syndrome: Energetic Stress, Calcium Homeostasis and mTOR Pathway

Isomorphic mutation of SBDS gene is the cause of Shwachman-Diamond syndrome (SDS). SDS is a rare genetic bone marrow failure and cancer predisposition syndrome. SDS cells have altered ribosome biogenesis and protein synthesis, two high-energy consuming cellular processes. The reported increment in reactive oxygen species production, endoplasmic reticulum stress response and reduced mitochondrial functionality suggest a defect in the energy production in SDS cells.In this study, we analyzed the energetic metabolism in SDS cells and find that the oxygen consumption is impaired when it is induced by pyruvate/malate or succinate. This induces poor ATP production and AMP accumulation with a consequent alteration in the ATP/AMP ratio. Also respiratory chain activity was impaired because of faulty function of the complex IV; this defect is not dependent from impaired protein synthesis despite ribosome biogenesis and transduction defects in SDS. In fact, COX5A and Cox2, two subunits of Complex IV encoded respectively by a nuclear and mitochondrial gene, were expressed at normal levels. Impaired function of complex IV could be due to an increment of cytoplasmic calcium concentration that inhibits complex IV activity.Energetic stress induces changes in cellular metabolism, stimulating or inhibiting a network of molecules involved in regulation of energetic balance, such as AMPK and mTOR. In SDS cells as consequence of energetic stress, AMPK is hyper activated and the glycolytic pathway stimulated. Surprisingly, we found that also the AKT/mTOR pathway is aberrantly hyper activated since both these proteins are hyper-phosphorylated. We can speculate that hyper activation of mTOR is a way through which SDS cells support the energy defect and protein synthesis. All these defects were recovered when the SDS cells were complemented with SDS gene.Finally, leucine is an essential amino acid that induces cell proliferation and protein synthesis, restored OXPHOS and ATP synthesis, reduced the cytoplasmic calcium concentration and the AMPK and AKT/mTOR activity, and improved in vitro erythropoiesis from SDS individuals pointing to leucine as potential tool helpful to sustain deranged energetic metabolism and erythropoiesis in SDS patients.In conclusion, we report for the first time that SDS cells suffer of energetic stress and severe respiratory defect that is related to faulty SBSD protein. These defects are compensated by an enhanced activation of AMPK, glycolysis and mTOR/Akt pathways, which appear to adequately support protein synthesis. A pivotal role in the maintenance of this altered metabolism could be played by altered calcium homeostasis. Noteworthy biochemical defects might be largely corrected by leucine which also favourably affects in vitro erythropoiesis thus pointing to biochemical defects as important determinant for impaired hematopoiesis od SDS. DisclosuresDufour:Pfizer: Consultancy.

Influence of lapse of time when measuring causes and effects in the consumption of online services

The intention to continue to use is a basic variable in the processes of consuming goods and services because such intention affects the organizations' wealth and surviving capacities. Commonly, researchers measure the continuance intention when the users are still receiving the service. Contrariwise, the main contribution of the present research is to measure the variables of consumer behavior as a sequence of events, thus providing a time gap that allows researchers to detect and measure the causes and the effects in the relationships among variables. The conclusions of the research are relevant both from an epistemological viewpoint and from the perspective of the marketing strategies suitable for services whose consuming processes are susceptible to time lapses.