Anthocyanin profile of red fruits and black carrot juices,purees and concentrates by HPLC‐DAD‐ESI/MS‐QTOF

A fast and reliable method for anthocyanin extraction and identification by HPLC‐DAD‐ESI/MS‐QTOF was used to analyse the anthocyanin composition of commercial red fruit juices (blackberry, redcurrant and pomegranate), purees (strawberry, cherry and raspberry) and concentrates (elderberry, blueberry and red grape). The anthocyanin profile of black carrot juice is also reported. The extraction and analysis method allowed us to detect and quantify a wide range of individual anthocyanins in a simple and rapid way. Pelargonidin‐3‐glucoside was detected in redcurrant for the first time and petunidin‐3‐galactoside quantified for the first time in blueberries. Considering the health benefits that have been associated with anthocyanin consumption, all these fruit and vegetables processed products could appear as a good source of this group of phytochemical compounds for their direct consumption or their use as ingredients for the design of new food product or food supplements.     

The effect varied scanning electron microscopy desiccation techniques has on demineralized dentin

The study objective was to assess (a) the effect of a rubbing‐application of ethylenediaminetetraacetic acid (EDTA) or citric acid (CA) has on the ultrastructure of surface dentin and (b) the effect of two scanning electron microscopy (SEM) desiccation preparation techniques have on the collagen surface produced. Treatment regions on proximal root surfaces of extracted human teeth were root planned to expose dentin. Cotton pellets soaked in either 30% CA or 24% EDTA solution were rubbed on the treatment region then processed for SEM using one of two desiccation techniques, that is, (a) critically point dried from liquid CO₂ (control) or (b) air‐dried from tetramethylsilane (experimental). Specimens were coated with gold/palladium and viewed/photographed with an SEM. Specimens of the control groups displayed tufted fibrils (CA > EDTA) with many dentin tubules being partially obscured by overhanging fibrils. Air‐dried specimens of both treatment groups displayed a flat intact monolayer devoid of a matted meshwork of fibrous collagen. Discrete fibril “sprigs,” emanating from the surface monolayer, were characteristic of the EDTA group only. The rubbing‐application of EDTA on dentin produces a tufted fibril surface somewhat similar to that produced by CA. Air‐drying desiccation of both resulted in marked distortion with fibril collapse/coalescence of the tufted collagen matrix.     

Evidence for false-positive results for boldenone testing of veal urine due to faecal cross-contamination during sampling.

European Directive 96/22/EC, which controls veterinary residues in animals, does not permit the presence of synthetic growth promoters in products of animal origin or in livestock. Boldenone is categorized in class A3 (growth promoters -- steroids) and is thus a banned substance. Testing of veal urine for banned substances is part of the European Union statutory programme for animals going into the food chain. In relation to this monitoring, three studies were conducted to investigate the apparent presence of the banned growth promoter boldenone in veal urine, which was suspected as being caused by interference from faecal contamination of the sample. In the first study, urine samples were collected at different times (time 0 and after 30 min) using (1) a conventional zoonotechnical apron and (2) a technique designed specifically to avoid faecal contamination ('kettle'). This resulted in samples that were, respectively, positive and negative for the presence of alpha-boldenone (alpha-BOL). In a second study, urine samples negative to alpha-BOL were collected from eight veal calves, but became positive after deliberate faecal contamination. In a third study, data obtained from the Italian RNP (Residual National Program) indicated that 18.1% of 3295 urine samples collected using the zootechnical apron were positive for alpha-BOL and 2.1% for beta-boldenone (beta-BOL), whilst of 902 samples collected using the kettle, beta-BOL was not detected in any samples and only 0.2% were positive to alpha-BOL, in concentrations lower than 2 ng ml(-1). These results further support the supposition that faecal contamination of the urine during sample collection can lead to false-positive results during boldenone analysis.     

5,5-trans lactone-containing inhibitors of serine proteases: identification of a novel, acylating thrombin inhibitor

Synthesis of a variety of 5,5-trans fused lactones, related to compounds found in extracts of Lantana camara, has provided a series of novel acylating inhibitors of human thrombin, trypsin, chymotrypsin and human leucocyte elastase. The most effective thrombin inhibitor is 7 with an IC50 of 130 nM and a Kobs/[1] of 4,000 M-1 s-1.     

Leukocyte flow properties, polymorphonuclear membrane fluidity and cytosolic Ca2+ content in subjects with vascular atherosclerotic disease

Hereditary predisposition to thrombosis due to activated protein C resistance (APCR) has been attributed to a missense mutation in the factor V gene at nucleotide 1691 (G to A), causing replacement of arginine at codon 506 with glutamine. Using an RFLP-PCR assay to detect this mutation, we measured a prevalence of 3.3% in healthy Caucasians and 1.25% in healthy African-Americans. In addition, we evaluated a total of 90 consecutive specimens submitted to the coagulation laboratory at the Medical College of Virginia for the presence of this mutation. We compared our results for 78 of these specimens with the values measured by a modified partial thromboplastin assay, the COATEST. Twelve of the 90 samples could not be tested using the COATEST because the patients were undergoing anticoagulant therapy. One of the latter 12 specimens was positive by the RFLP-PCR test. Using the genetic test as the definitive assay and the cutoff value established for distinguishing between normal and abnormal results by the COATEST, the COATEST had a sensitivity of 50% and specificity of 93% for the detection of factor V mutation. Analysis of the 90 samples stratified by ethnic groups revealed a frequency of mutation of 13.3% for Caucasians and 6.88% for African-Americans, although with the present sample size, the difference was not statistically significant. Although the COATEST is technically simpler to perform than the genetic test for diagnosing the presence of the factor V mutation, its use for this purpose is limited due to low sensitivity. Thus where this disorder is clinically suspected, submission of the specimen directly for genetic testing by RFLP-PCR or equivalent assay should be considered.     

Adaptive reconfiguration of data networks using genetic algorithms

Genetic algorithms are applied to an important, but little investigated, network design problem, that of reconfiguring the topology and link capacities of an operational network to adapt to changes in its operating conditions. These conditions include: which nodes and links are unavailable; the traffic patterns; and the quality of service (QoS) requirements and priorities of different users and applications. Dynamic reconfiguration is possible in networks that contain links whose endpoints can be easily changed, such as satellite channels, terrestrial wireless connections, and certain types of optical connections. We report preliminary results that demonstrate the feasibility of performing genetic search quickly enough for online adaptation.     

Discrete Critical Values: a General Framework for Silhouettes Computation

Many shapes resulting from important geometric operations in industrial applications such as Minkowski sums or volume swept by a moving object can be seen as the projection of higher dimensional objects. When such a higher dimensional object is a smooth manifold, the boundary of the projected shape can be computed from the critical points of the projection. In this paper, using the notion of polyhedral chains introduced by Whitney, we introduce a new general framework to define an analogous of the set of critical points of piecewise linear maps defined over discrete objects that can be easily computed. We illustrate our results by showing how they can be used to compute Minkowski sums of polyhedra and volumes swept by moving polyhedra.     

Thermal performance analysis and economic evaluation of roof-integrated solar concrete collector

This paper examines the thermal performance of a roof-integrated solar concrete collector for reducing heat gain to a house and providing domestic hot water. The solar concrete collector is made of PVC pipes embedded in deck slab or concrete roof. No glazing on the top of the solar concrete collector or insulation at the back has been used as in conventional solar water heaters. To compare the energy saving, two test rooms of 2.3 m width, 2.5 m length and 2.5 m height were built. In the first room, the reinforced cement concrete (R.C.C.) slab was used as deck slab whereas the second room was equipped with a cement concrete solar collector. The experimental results showed that the cement concrete solar collector is extremely interesting as it can produce up to 40 l of hot water per day at water temperatures ranging from 40 to 50 °C. A mathematical model based on the conservation equations of energy is developed to predict the performance of the cement concrete solar collector. There is reasonable agreement from the comparison between measured data and predicted results. The economic analysis indicates that the payback period is rather fast.     

Minimum number of islets required to maintain euglycemia and their reduced immunogenicity after transplantation into diabetic mice

In streptozocin (SZ)-induced diabetic mice, 200 islets, but not 50 islets, consistently restore euglycemia within 1 week of transplantation. To determine the minimum number of islets sufficient to maintain euglycemia in a diabetic mouse, we first transplanted 50 and 150 syngeneic islets simultaneously into the right (RK) and left kidney (LK), respectively, and then removed the LK 1 week post-transplantation. The remaining 50 islets maintained euglycemia in 8 of 11 mice with normal intravenous glucose tolerance tests (IVGTT). Protection of 50 islets for at least 7 days was necessary because removal of the 150 islets at 5 or 3 days resulted in a much lower incidence of persistent euglycemia. Similarly, 25 islets were capable of maintaining euglycemia in 2 of 9 mice once hyperglycemia was reversed by split-transplantation of 25 (RK) and 175 (LK) islets. To examine if 50-islet allografts survive longer than 200-islet allografts, we split-transplanted 50 DBA/2 islets in the RK and 150 islets of either B6 (syngeneic), DBA/2 (allogeneic), or C3H/He (third party allogeneic) mouse origin in the LK in 3 groups of diabetic C57BL/6 (B6) mice. The survival of 50 DBA/2 islets in each group after removal of the LK on day 7 was compared to that of 200 DBA/2 islets in control B6 mice. Maximum prolongation of allograft survival was obtained with 50 DBA/2 islets that were split-transplanted with syngeneic B6 islets. These results clearly demonstrate that 50 islets are sufficient to maintain normal glucose tolerance once euglycemia is induced by transplantation of a larger number (i.e., 200) of islets and that 50 islet allografts are much less immunogenic than 200-islet allografts.