Economic evaluation of long-distance hydrogen transmission by chemical closed-loop cycle

All over the world there are enormous unexploited renewable energy reserves (hydro, geothermic, solar, wind, etc.). Most originate far from the location of the users, so their exploitation would greatly benefit from the disclosure of new, more economical, and technically feasible transmission systems.A possible alternative to electricity is the use of hydrogen as a medium for transportation of energy. This work proposes a chemical closed-loop cycle based upon catalytic reversible reactions as a means to transmit hydrogen. A real example for the application of the proposed system for transportation of secondary energy was considered. In particular, choosing a large hydro-electric source as reference, a comparison was made between costs and efficiencies in transferring energy as hydrogen (in its different forms) over long distances, with respect to transportation of the same energy as electricity.     

Use of the ARPE-19 cell line as a model of RPE polarity: basolateral secretion of FGF5

PURPOSE: To determine the polarity of fibroblast growth factor 5 (FGF5) secretions from retinal pigment epithelium (RPE) cells and to examine the viability and utility of the ARPE-19 cell line as a model for the study of RPE polarity. METHODS: Influenza infection and adenovirus-mediated gene transfer were used to deliver and express genes encoding influenza hemagglutinin (HA), p75-NTR (a neurotrophin receptor), low-density lipoprotein (LDL) receptor (LDLR), and FGF5 in confluent monolayers of ARPE-19 cells. The localization of HA, p75-NTR, and LDLR was determined by confocal microscopy. Domain selective biotinylation assays were used to quantitatively determine the polarities of p75-NTR and LDLR. The secretion of FGF5 into the apical and basal media of ARPE-19 cultures was examined by immunoblot analysis of conditioned media. RESULTS: Hemagglutinin and p75-NTR were found to be localized on the apical surface of infected and transduced ARPE-19 cells. In contrast, LDLR was associated preferentially with the basolateral membrane of ARPE-19 cells. Biotinylation studies indicated that 84% of p75-NTR was present on the apical surface, and 79% of LDLR was basolaterally polarized. Over the course of 6 hours, more than 90% of the total secreted FGF5 protein accumulated in the basolateral media. CONCLUSIONS: ARPE-19 cells exhibit a polarized distribution of cell surface markers when examined by either confocal microscopy or surface-labeling assays. This indicates that the ARPE-19 cell line is a valid model for studies of RPE cell polarity. FGF5, a secreted protein normally produced by RPE cells, is accumulated preferentially in the basal media after only 6 hours, suggesting that it is vectorially secreted from the basolateral surface of ARPE-19 cells.     

Synthesis of crystalline metal nitride and metal carbide nanostructures by sol–gel chemistry

Attention toward nanosized metal nitrides and carbides is rapidly increasing thanks to their chemical characteristics that make them as valid and sustainable alternatives to noble metals in catalysis and to air-sensitive metals or oxides for applications under harsh conditions. They are mostly used as bulk phase or micron sized powders, due to an intrinsic difficulty to synthesize them as nanoparticles in a systematic and scalable fashion. However, nanosized metal nitrides and carbides could exhibit improved performances, e.g. in catalysis due to a higher surface area, and can be shaped more easily than corresponding larger grains for further specific applications. Recently, sol–gel chemistry has closed this gap and now enables the simple, cheap, and sustainable production of metal nitride and carbide nanoparticles.In the present review we give an overview on recent sol–gel based pathways for the synthesis of metal nitride and carbide nanoparticles, believing that a better knowledge of the potentialities of these still hardly touched materials stimulates research interest and applications.     

Microstructured fibre Bragg gratings: analysis and fabrication

A microstructured fibre Bragg grating that relies on a partial and localised etching of the cladding layer along the grating region is proposed. The main effect is the formation of defect states inside the bandgap depending on surrounding refractive index. This leads to the possibility of realising novel optoelectronic devices for sensing and telecommunication applications.     

Dual carrier suppression interferometer for measurement of phasenoise

A new scheme for phase noise measurement is presented, based on dual stage suppression of the carrier and synchronous detection of the noise sidebands of the device being tested. This scheme features real time output and intrinsically low instrument flicker. A prototype shows a residual flicker as low as -160 dBrad²/Hz at 1 Hz off the 100 MHz carrier. Other implementations are possible, from 1 MHz to several gigahertz. Applications include the noise characterisation of components and the design of innovative ultrastable oscillators     

A Fiber-Optic Bragg Grating Seismic Sensor

Here we present a fiber-optic seismic waves sensor based on in-fiber Bragg gratings. Fiber-Bragg-grating (FBG) sensors have been demonstrated to have very high sensitivity to dynamical strain and very extended dynamical response. The seismic sensing system is based on the integration of three FBGs' dynamical strain sensors in a mechanical structure acting as an inverse pendulum. Polar symmetry of the mechanical system and 120deg placement of the FBG sensors could enable directional capability of the seismic sensor. Design, manufacturing, and preliminary dynamical testing of the seismic sensor are discussed.     

Effect of dry‐heat treatments on the nutritional value of maize germ

Maize germ is a by‐product of the maize milling process that is characterised by a high nutritional value. Currently, heat treatments are employed to prevent full‐fat maize germ from spoilage. The aim of this research was to study the effect of five dry‐heat treatments on the nutritional value of full‐fat maize germ. The results confirmed that after each dry‐heat treatment, the lipase activity decreases but the use of high temperatures could be detrimental for phytosterol and thiamine concentrations. The main negative effects have been observed after treatments at 140 °C for 30 min and 160 °C for 10 min. No significant difference has been observed for protein, ash or fatty acid contents. The treatment at 140 °C for 20 min resulted an optimal combination between temperature and heating time to inactivate lipase without altering deeply the nutritional value and the colour of maize germ.     

Dietary krill oil increases docosahexaenoic acid and reduces 2-arachidonoylglycerol but not N-acylethanolamine levels in the brain of obese Zucker rats

Evidence suggests that dietary long chain polyunsaturated fatty acids (LCPUFAs), and particularly those belonging to the n-3 family, may influence the brain fatty acid profile and, thereby, the biosynthesis of endocannabinoids in rodents. However, the doses used are usually quite high and not comparable with human intake. Recently, we have shown that relatively low doses of dietary n-3 LCPUFAs (4 weeks), in the form of either fish or krill oil, balanced for EPA and DHA content, and against a control diet with no EPA and DHA and similar contents of oleic, linoleic and α-linolenic acids, lower the concentrations of the endocannabinoids, anandamide (AEA) and 2-arachidonoylglycerol (2-AG), in the visceral adipose tissue, and of AEA in the liver and heart, of obese Zucker rats. This, in turn, is associated with lower levels of arachidonic acid in membrane phospholipids and with amelioration of some metabolic syndrome parameters. We investigated here whether in Zucker rats, under the same conditions, fish and krill oil are also able to influence LCPUFA and endocannabinoid profiles in brain. Only krill oil was able to increase significantly DHA levels in brain phospholipids, with no changes in arachidonic acid. DHA increase was associated with lower levels of 2-AG in the brain, whereas AEA and its congeners, N-palmitoylethanolamine and N-oleoylethanolamine, were unchanged. We conclude that, despite the strong impact of dietary n-3 fatty acid on endocannabinoid levels previously observed in peripheral tissues, in the brain only 2-AG is affected by dietary krill oil, suggesting that the beneficial effect of the latter on the metabolic syndrome is mostly exerted by modifying peripheral endocannabinoids. Nevertheless, possible effects of dietary krill oil in the brain through modification of 2-AG levels deserve further investigation.     

Presynchronization with Double-Ovsynch improves fertility at first postpartum artificial insemination in lactating dairy cows

The objective of this study was to compare circulating progesterone (P4) profiles and pregnancies per AI (P/AI) in lactating dairy cows bred by timed artificial insemination (TAI) following Ovsynch-56 after 2 different presynchronization protocols: Double-Ovsynch (DO) or Presynch-Ovsynch (PS). Our main hypothesis was that DO would increase fertility in primiparous cows, but not in multiparous cows. Within each herd (n = 3), lactating dairy cows (n = 1,687; 778 primiparous, 909 multiparous) were randomly assigned to DO [n = 837; GnRH-7d-PGF_2α-3d-GnRH-7d-Ovsynch-56 (GnRH-7d-PGF_2α-56h-GnRH-16hTAI)] or PS (n = 850; PGF_2α-14d-PGF_2α-12d-Ovsynch-56). In 1 herd, concentrations of P4 were determined at the first GnRH (GnRH1) of Ovsynch-56 and at d 11 after TAI (n = 739). In all herds, pregnancy was diagnosed by palpation per rectum at 39 d. In 1 herd, the incidence of late embryo loss was determined at 74 d, and data were available on P/AI at the subsequent second service. Presynchronization with DO reduced the percentage of animals with low P4 concentrations (<0.50 ng/mL) at GnRH1 of Ovsynch-56 (5.4 vs. 25.3%, DO vs. PS). A lesser percentage of both primiparous and multiparous cows treated with DO had low P4 concentrations at GnRH1 of Ovsynch-56 (3.3 vs. 19.7%, DO vs. PS primiparous; and 8.8 vs. 31.9%, DO vs. PS multiparous). Presynchronization with DO improved P/AI at the first postpartum service (46.3 vs. 38.2%, DO vs. PS). Statistically, a fertility improvement could be detected for primiparous cows treated with DO (52.5 vs. 42.3%, DO vs. PS, primiparous), but only a tendency could be detected in multiparous cows (40.3 vs. 34.3%, DO vs. PS, multiparous), consistent with our original hypothesis. Presynchronization treatment had no effect on the incidence of late embryo loss after first service (8.5 vs. 5.5%, DO vs. PS). A lower body condition score increased the percentage of cows with low P4 at GnRH1 of Ovsynch-56 and reduced fertility to the TAI. In addition, P4 concentration at d 11 after TAI was reduced by DO. The method of presynchronization at first service had no effect on P/AI at the subsequent second service (34.7 vs. 36.5%, DO vs. PS). Thus, presynchronization with DO induced cyclicity in most anovular cows and improved fertility compared with PS, suggesting that DO could be a useful reproductive management protocol for synchronizing first service in commercial dairy herds.