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Recently, the utilisation of essential oils extracted from spices has been garnering interest due to their phytochemical constituents which could be extracted using various techniques. Studies have demonstrated antimicrobial activities from essential oils against foodborne pathogens, and thus, their application has been considered to be a possible preservative for foods. Pimenta dioica is a type of aromatic plant, and its essential oil is is rich in eugenol, a phenolic compound with wide antimicrobial spectrum. Other bioactive compounds in P. dioica extract include glycosides, alkaloids, carbohydrates, proteins, flavonoids, and tannins. The incorporation of essential oils into food is limited because they have an intense aroma, and might affect consumer acceptance. Therefore, nanotechnology is applied as a tool to rectify this limitation, and it is now possible to apply essential oils in active packaging, or to encapsulate them in biodegradable materials or edible coatings with controlled release. However, there is little information on the interaction of nanoencapsulated bioactive composites, and thus, it is essential to assess the viability of biomaterials before their use. The objective of this work is to show the use of the essential oil of Pimenta dioica and its phytochemical composites in a general way for its potential application in food technology. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate the diagnostic performance of 18F-choline PETCT in staging prostate cancer (PC) and whether the use of this imaging modality changes the therapeutic decision in patients previously staged by conventional imaging. The secondary aim was to determine the prognostic factors associated with positive choline PETCT findings in both detection of disseminated disease and in changes in the therapeutic indication. Materials and methods: Multicentre, retrospective, observational study of 269 patients diagnosed with PC. Mean age was 69 ± 9.2 years. Of the 269 patients, 62 (23%) had high-risk localized PC (group 1), 118 (43.9%) biochemical failure after radical prostatectomy (group 2), and 89 (33.1%) biochemical failure after radiotherapy (group 3). None of the patients showed clear evidence of distant disease on computed tomography or bone scans. The following potential prognostic factors were assessed: PSA level at diagnosis; primary and secondary Gleason; Gleason score (GS); clinical and pathologic T and N stage; number of positive cylinders in the biopsy; presence of vascular or lymphatic invasion; status of surgical margins; androgen deprivation therapy (ADT); time to biochemical recurrence; and PSA, PSA doubling time (PSADT), and PSA velocity (PSAV) at failure. Univariate and multivariate analyses were performed, and receiver-operating curves calculated. Results: The mean PSA by groups was, group 1: 31.22 ng/ml, group 2: 2.52 ng/ml and group 3: 5.85 ng/ml. The tumor detection rate with 18F-choline PETCT was 74% (group 1: 85.5%, group 2: 55.1% and group 3: 91%). Prognostic factors for positive 18F-choline PETCT were identified only in group 2: PSA at failure and PSADT. 18F-choline PETCT changed the therapeutic indication in 62.8% (group 1: 71%, group 2: 55.2% and group 3: 70.1%). The prognostic factors for a change in treatment were identified only in group 1: secondary Gleason ≤ 4 and GS ≤ 7 and in group 2: PSA at failure, PSA nadir after surgery and pathologic stage N0. 18F-choline PETCT identified lymph node and/or metastatic disease in 32.7% (group 1: 25.8%, group 2: 29.7% and group 3: 41.6%). Prognostic factors for detecting lymph node/metastasis were identified in the group 2: PSA failure ≥ 1.37 ng/ml and PSADT < 4 months and in the group 3: PSADT < 4.6 months and time to failure < 5 years. Conclusion: These findings support the clinical use de 18F-choline PET-CT in staging high-risk patients with a secondary Gleason ≤ 4 and GS ≤ 7, in restaging patients with biochemical recurrence after RP if PSA at failure ≥ 1.37 ng/ml or PSADT ≤ 4 months and in patients with biochemical failure after RT, if PSADT ≤ 4.6 months and time to failure < 5 years, because it determines a change in the therapeutic indication. [ABSTRACT FROM AUTHOR]

Presents a study which investigated selenium-related DX centers in AlGaAs alloys using deep-level transient spectroscopy (DLTS) and constant-capacitance DLTS. Sample preparation; Experimental results and discussion; Conclusions.

Presents a study that analyzed the generation-recombination processes in semiconductors by numerical simulation. Occurrence of current saturation; Description of generation-recombination in the space-charge zone; Saturation of the generation-recombination rate.

Characterizes the DX centers in aluminum gallium arsenide: silicon alloys doped with silicon. Impurities of the deep centers; Optical emission processes of DX centers; Admittance spectroscopy of DX centers.

Direct Steam Generation in Parabolic Troughs or Linear Fresnel solar collectors is a technology under development since beginning of nineties (1990's) for replacing thermal oils and molten salts as heat transfer fluids in concentrated solar power plants, avoiding environmental impacts. In parallel to the direct steam generation technology development, supercritical Carbon Dioxide Brayton power cycles are maturing as an alternative to traditional Rankine cycles for increasing net plant efficiency and reducing balance of plant equipments dimensions and cots. For gaining synergies between these two innovative technologies, in this paper, Direct Steam Generation and Brayton power cycles are integrated in line-focusing solar power plants. Four configurations are studied: Configuration 1 consists on installing a condenser between solar field and power cycle; condensing the heat transfer fluid (steam water) with the balance of plant working fluid (carbon dioxide). The condenser would be a shell & tubes type. Along tubes carbon dioxide flows, and steam water condensates at shell-side. Main advantage of the condenser equipment is the high heat transfer coefficient at water condensing-side, reducing condenser dimension and weight. The main disadvantage of this configuration is the high operating pressure required in solar field for condensing steam into liquid water. This pressure should be between 150 bar and 175 bar for obtaining 400 °C at turbine inlet. In the Configuration 2, the superheated steam delivered by solar collectors transfers the heat energy in a primary heat exchanger to the balance of plant working fluid. In this configuration the steam not condensate into liquid water, and only reduces the temperature from 550 °C–560 °C to 420 °C. The steam pressure drops in solar field along receivers, headers and heat exchangers are compensated by means of steam compressors. This second solution is compatible with higher turbine inlet temperatures, up to 550 °C. The keystones of this second configuration are the steam conditions at compressor inlet, pressure ∼175 bars and temperature ∼420 °C, for minimizing steam compressor electrical consumption. The third design solution (Configuration 3) includes a solar field with direct steam generation in solar collectors with boiling recirculation mode, but the balance of plant is integrated by two Brayton power cycles in cascade. The first power cycle operating at 550 °C turbine inlet, and the second cycle at 410 °C turbine inlet. Main advantage is the integration between a validated direct steam generation technology (recirculation boiling mode) with the Brayton power cycles avoiding steam compressors, a technology not yet commercially available, and main drawback of this design is the increasing number of balance of plant equipments. The Configuration 4 is very similar to the Configuration 2, with the same direct steam generation solar field with superheated steam without condensing, and a single reheating stage solar field with molten salt as heat transfer fluid. The Configuration 1 provides similar efficiency and net power output, for similar solar field effective aperture area, as obtained with molten salt solar collectors with supercritical carbon dioxide power cycle (recompression with main compression intercooling cycle provides 36.6% net efficiency, for a maximum 400 °C turbine inlet). The second design solution (Configuration 2) net efficiency is not very much impacted for steam compressor electrical consumption recompression cycle net efficiency is 43.6% with steam solar field, versus 45.16% with molten salt solar field, in both cases with 550 °C turbine inlet. The Configuration 3 performance is ∼39.7% with two cascade Brayton power cycles with recompression and main compression intercooling. Finally, the Configuration 4 optimum plant performance is obtained for the recompression cycle with a net efficiency ∼45.77%, and is constrained by the molten salt drawbacks (material corrosion, material cost, environmental impact, etc). [ABSTRACT FROM AUTHOR]

This study reports the characterization of the Tetrasphaera duodecadis bacteria and the techniques used therein. In order to evaluate the morphological characteristics of the T. duodecadis bacteria scanning electron microscope (SEM) was used throughout its different growth stages. These microorganisms were grown in vitamin B12 broths with 1% tryptone, 0.2% yeast extract, and 0.1% glucose. The turbidimetric method was employed for the determination of bacterial concentration and growth curve. The SEM results show small agglomerates of 0.8 ± 0.05 µm during the lag phase, and rod-like shapes during the exponential phase with similar shapes in the stationary phase. SCANNING 36:547-550, 2014. © 2014 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Highlights: [•] Greenhouse cover type and photoperiod affects the tomato lycopene content. [•] Tomatoes growing in March under double layer polyethylene had higher lycopene content. [•] The CaCO3 application on glass cover flat decreased the lycopene content. [•] Tomato fruits receiving greater amounts of light accumulated more lycopene. [ABSTRACT FROM AUTHOR]

In this article a current-mode, second-order, CT Sigma-Delta modulator operating at a sampling frequency of 25 MHz and with an oversampling ratio of 64 has been designed. The modulator consists of current-mode, differential integrators based on a single-stage folded cascode topology and switched capacitors DACs cells generating exponential feedback waveforms. The modulator was analysed in detail from both a system- and a circuit-level point of view. A 'short' exponential DAC pulse, namely, an exponential pulse whose time constant is lower than the pulse width, was used to improve jitter rejection. Modulator feedback coefficients were analytically derived for an exponential feedback waveform. Jitter considerations paying special attention to its impact on CT Sigma-Delta modulators were presented, and two different contributions distinguished: independent jitter and accumulated jitter. Finally, functional- and transistor-level simulations have been accomplished to obtain significant features of the modulator performance. [ABSTRACT FROM AUTHOR]

A very low voltage solution for the realization of the hold capacitor in a Track&Hold circuit based on an open-loop architecture is introduced. The circuit is a modification based on the switched opamp approach of the Track&Hold circuit using Miller Capacitance. Simulations show that the circuit is able to operate at 1V 1MS/s with a Total Harmonic Distortion of -64 dB @ 100 kHz and a very low power consumption of 80 µW. [ABSTRACT FROM AUTHOR]

Objective: The aim was to review and update advances in genetics of obesity.Design: Analysis and interpretation of recent investigations about regulating the energy balance as well as about gene-nutrient interactions and current nutri-genomic research methods. BACKGROUND AND MAIN STATEMENTS: Obesity results from a long-term positive energy balance. However, its rising prevalence in developed and developing societies must reflect lifestyle changes, since genetic susceptibility remains stable over many generations. Like most complex diseases, obesity derives from a failure of adequate homoeostasis within the physiological system controlling body weight. The identification of genes that are involved in syndromic, monogenic and polygenic obesity has seriously improved our knowledge of body weight regulation. This disorder may arise from a deregulation at the genetic level (e.g. gene transcription or altered protein function) or environmental exposure (e.g. diet, physical activity, etc.).Conclusions: In practice, obesity involves the interaction between genetic and environmental factors. [ABSTRACT FROM AUTHOR]

Highlights Nowadays, non‐timber sources are of greater interest as they avoid deforestation and the pollution which occurs with cellulose obtention. An emerging alternative is using weeds such as windmill grass (Chloris spp.) to isolate cellulose since the plant grows in large quantities near crops or landfills used for farming. The present study aims to explore windmill grass as an alternative source of cellulose for applications as reinforcement in biopolymeric matrices. Treatment was conducted using the peroxyformic pulping method, varying the formic acid (FA) and hydrogen peroxide (HP) concentration to obtain an optimum cellulose extraction condition. The isolated celluloses were analyzed for chemical composition, yield, chemical functionality, crystallinity, and morphology. The optimum pulping condition (FA = 87.5%, HP = 3%) shows the gradual removal of non‐cellulosic components by microscopy. X‐ray diffraction analysis revealed a high crystallinity index (89.63%) with a characteristic cellulose type I pattern. To evaluate the reinforced effect of Chloris spp. celluloses, film formulations were made using sweet potato starch, glycerol, and cellulose at different concentrations (2.5, 5.0, and 7.5% w/w). The films' mechanical, physicochemical, and thermal properties were measured, and results indicate that adding cellulose fibers significantly improves these properties of sweet potato starch films, revealing further applications and non‐wood windmill grass added value with potential applications in the packaging sector. Windmill grass (Chloris spp.) is presented as a non‐wood source of cellulose. The peroxyformic method is reported as a less polluting cellulose extraction process. Optimal cellulose pulp presents enhanced physicochemical properties after bleaching. Cellulose‐reinforced sweet potato starch films exhibit a stable biopolymeric matrix. The films produced show enhanced water barrier and mechanical/thermal properties. [ABSTRACT FROM AUTHOR]

In this paper, a 10-bit 40-MS/s analog-to-digital converter (ADC) is presented. A power consumption of 12 mW was achieved by using a time-interleaved and pipelined architecture with shared operational amplifiers. This circuit was fabricated in a 2.5-V 0.25-μm technology with metal—oxide—metal capacitors. Experimental results are within design ranges and are in good agreement with simulation data. It turns out that the proposed Nyquist-rate ADC provides a potential solution for low-power high-speed applications, e.g., wireless LANs. [ABSTRACT FROM AUTHOR]