Identification and quantitation of vitamins K1 and K3 in cosmetic products for facial skin protection

A simple and rapid analytical method was developed for the determination of vitamins K1 and K3 in facial anti-rash creams. The procedure is based on an ultrasonic extraction of the cosmetic sample with dimethylacetamide, in the presence of an internal standard, followed by HPLC separation. HPLC was performed using a C18 column and spectrophotometric detection at 333 nm. A linear gradient elution was carried out starting with 50% acetonitrile–methanol (75:25 v/v) and water up to 100% acetonitrile–methanol for 5 min. Linearity was established over the concentration range from 0.2 to 1.0 mg mL^-1 for vitamin K1 and from 0.02 to 0.1 mg mL^-1 for vitamin K3, with LOD values of 100 ng and 20 ng injected, respectively. The accuracy was verified by spiking experiments on model cosmetic samples. The proposed method has been successfully applied for the analysis of commercial samples of creams.     

Improving industrial suitability of incremental sheet forming process

Although in the last years a large amount of research work has been spent on incremental sheet forming process, industrial applications are not spreading accordingly. This is due to process characteristics such as slowness and limited accuracy. In the paper, the authors investigated the suitability of incremental sheet forming at very high feed rates to strongly reduce processing time. What is more, a simple strategy to reduce the part inaccuracy was implemented. The investigation concerned a simple conical shape but the obtained results are quite general.     

High-performance optical CDMA system based on 2-D optical orthogonal codes

Optical code-division multiple access (OCDMA) is an interesting subject of research because of its potential to support asynchronous, bursty communications. OCDMA has been investigated for local area networks, access networks, and, more recently, as a packet label for emerging networks. Two-dimensional (2-D) OCDMA codes are preferred in current research because of the flexibility of designing the codes and their higher cardinality and spectral efficiency (SE) compared with direct sequence codes based on on-off keying and intensity modulation/direct detection, and because they lend themselves to being implemented with devices developed for wavelength-division-multiplexed (WDM) transmission (the 2-D codes typically combine wavelength and time as the two dimensions of the codes). This paper shows rigorously that 2-D wavelength/time codes have better SE than one-dimensional (1-D) CDMA/WDM combinations (of the same cardinality). Then, the paper describes a specific set of wavelength/time (W/T) codes and their implementation. These 2-D codes are high performance because they simultaneously have high cardinality (/spl Gt/10), per-user high bandwidth (>1 Gb/s), and high SE (>0.10 b/s/Hz). The physical implementation of these W/T codes is described and their performance evaluated by system simulations and measurements on an OCDMA technology demonstrator. This research shows that OCDMA implementation complexity (e.g., incorporating double hard-limiting and interference estimation) can be avoided by using a guard time in the codes and an optical hard limiter in the receiver.     

Evaluation of sustainability of a city through fuzzy logic

The sustainable indicators are characterized by a low degree of aggregation and a high amount of information. An indicator must show a synthetic representation of a real environmental, by using a value or a parameter, so that they can be easily used by policy makers. It is necessary to connect, therefore, the various systems in an appropriately integrated sustainable system. The indicators need to be aggregated based on the structure of the data. Each indicator must to be defined through a weight with reference to another weighted indicator.     

A model to manage a large number of transactions: a case study

The aim of this paper is to present a model for the Computer Centre of an important Italian banking group. The model groups data and transactions to deal with the large dimension of the Centre. The transactions arrivals are considered as Posson stochastic variables and the probability values are estimated. Some computational results are given.     

Copper resistant human hepatoblastoma mutant cell lines without metallothionein induction overexpress ATP7B

Mutant human hepatoblastoma cell lines resistant to copper toxicity were isolated from mutagenized HuH7. Two copper resistant cell lines (CuR), CuR 23 and CuR 27, had reduced basal expression of metallothionein (MT) messenger RNA (mRNA) and exhibited minimal or no increase in resistance to cadmium or zinc toxicity. Copper uptake, efflux of newly transported copper, glutathione content, and efflux rate were comparable with HuH7, whereas holoceruloplasmin synthesis and secretion were slightly decreased. Subcellular distribution of copper at steady-state showed an increase in organelle and membrane fractions with a reduction in cytosol. Expression of ATP7B mRNA was fivefold increased, and ATP7B protein approximately threefold increased in both CuR 23 and 27. Another cell line, CuR 41, showed increased basal expression of MT and ATP7B mRNA but not ATP7B protein, and resistance to cadmium and zinc toxicity. Copper uptake in CuR 41 was comparable with HuH7, but initial rates of efflux of copper and glutathione were reduced. The synthesis of holoceruloplasmin but not ceruloplasmin peptide was markedly diminished in CuR 41. Subcellular distribution of copper showed an increase in cytosolic and decreased organelle and membrane-associated copper. These data suggest that cellular resistance to copper toxicity was achieved in two independent cell lines without MT induction and that the induction of ATP7B may lead to the enhanced intracellular sequestration of copper by organelles.     

Methodology for estimating saving of primary energy with membrane operations in industrial processes

Membrane separation processes can realize significant savings of direct energy (e.g., oil, gas, coal) and indirect energy (intrinsically contained in the materials recovered and/or recycled). The methodology of the energy analysis in various industrial cycles is described, and the benefits of these operations, based principally on electrical energy consumption, are evaluated using the definition of “substitution coefficient” (primary energy saved vs. 1 kWh of electrical energy consumed). The industrial sectors where this methodology has been applied are: textile (recycle of water, dyes and chemicals); polymer manufacturing (recycle of caprolactame and water); the tanning industry (recycle of sulfides and protein recovery), the dairy industry (saving of thermal energy and recovery of fat substances); and tomato and orange juice concentration (saving of thermal energy). The analyses show very interesting values for the substitution coefficients confirming the convenience of membrane operations from an energetic viewpoint.     

Synchronization Using Pulse Edge Tracking in Optical Pulse-Position Modulated Communication Systems

A pulse-position modulated (PPM) optical communication system using narrow pulses of light for data transmission requires accurate time synchronization between transmitter and receiver. The presence of signal energy in the form of optical pulses suggests the use of a pulse edge-tracking method of maintaining the necessary timing. In this report the edge-tracking operation in a binary PPM system is examined, taking into account the quantum nature of the optical transmissions. Consideration is given first to "pure" synchronization using a periodic pulsed intensity, then extended to the case where position modulation is present and auxiliary bit decisioning is needed to aid the tracking operation. Performance analysis is made in terms of timing error and its associated statistics. Timing error variances are shown as a function of system signal-to-noise ratio.     

Carbon nanowall growth on carbon paper by hot filament chemical vapour deposition and its microstructure

Carbon nanowall films were synthesized by plasma enhanced hot filament chemical vapour deposition on carbon paper, a three dimensionally structured material. The micro-structured nature of the carbon paper, which is composed of an irregular and open mesh of carbon fibres, allowed one to determine the microstructure of the carbon nanowalls both at the tip and at the fibre–nanowall base interface. The number of graphenes which pile up to form the structure of a single nanowall ranges from 1 to 2 at the tip up to several 10s at the base, making this material suitable to study and eventually exploit the electronic properties of graphenes on a macroscopic scale. Such material is promising for electrochemical applications.