Chaotic pulse position modulation to improve the efficiency of sonar sensors

Ultrasonic devices are widely used in robotics as exteroceptive sensors for ranging measurements. Robotic applications often involve a large number of sonars operating concurrently, giving rise to the phenomenon of crosstalk. In this work, the problem of improving performance of ultrasonic devices in the presence of crosstalk and noise is addressed. In order for each device to discriminate its own echo, chaos is exploited to create unique firing sequences. In particular, the firing scheme described in this work is inspired to a modulation scheme used in chaotic communications, called chaotic pulse position modulation (CPPM). The evaluation of the time of flight is performed by a detection filter. The experimental setup consists of a Polaroid 600 electrostatic transducer driven by a continuous CPPM modulator. Experimental results confirm the suitability of the approach.     

Complementary Effects of Carbamylated and Citrullinated LL37 in Autoimmunity and Inflammation in Systemic Lupus Erythematosus

LL37 acts as T-cell/B-cell autoantigen in Systemic lupus erythematosus (SLE) and psoriatic disease. Moreover, when bound to “self” nucleic acids, LL37 acts as “danger signal,” leading to type I interferon (IFN-I)/pro-inflammatory factors production. T-cell epitopes derived from citrullinated-LL37 act as better antigens than unmodified LL37 epitopes in SLE, at least in selected HLA-backgrounds, included the SLE-associated HLA-DRB1*1501/HLA-DRB5*0101 backgrounds. Remarkably, while “fully-citrullinated” LL37 acts as better T-cell-stimulator, it loses DNA-binding ability and the associated “adjuvant-like” properties. Since LL37 undergoes a further irreversible post-translational modification, carbamylation and antibodies to carbamylated self-proteins other than LL37 are present in SLE, here we addressed the involvement of carbamylated-LL37 in autoimmunity and inflammation in SLE. We detected carbamylated-LL37 in SLE-affected tissues. Most importantly, carbamylated-LL37-specific antibodies and CD4 T-cells circulate in SLE and both correlate with disease activity. In contrast to “fully citrullinated-LL37,” “fully carbamylated-LL37” maintains both innate and adaptive immune-cells’ stimulatory abilities: in complex with DNA, carbamylated-LL37 stimulates plasmacytoid dendritic cell IFN-α production and B-cell maturation into plasma cells. Thus, we report a further example of how different post-translational modifications of a self-antigen exert complementary effects that sustain autoimmunity and inflammation, respectively. These data also show that T/B-cell responses to carbamylated-LL37 represent novel SLE disease biomarkers.     

A universal design resource for rich Internet applications based on design patterns

Rich Internet applications have removed most of the constraints of Web 1.0 while giving users more responsiveness and advanced browsing and interaction experiences. These new horizons, however, raise many challenges for people with disabilities or using limited hardware and software technologies, whose risk to be excluded from the benefits deriving from advanced web applications. To address this problem, WCAG 2.0 guidelines have been released as the newest World Wide Web Consortium recommendation for accessible web content, and WAI-ARIA is a candidate recommendation which provides reference specifications for accessible rich Internet applications. However, both specifications contain a huge amount of information that often discourages most web designers from dealing with accessibility issues. Moreover, guidelines are suitable and usually adopted to judge a design solution a posteriori, but they do not suggest how to face a design problem constructively. This paper proposes a design pattern language for accessibility. The language can be regarded as a universal design resource for helping web designers create accessible rich Internet applications compliant with the most recent standards. Knowledge representation through design patterns reflects the problem-solving approach usually followed by software and web designers, while pattern organization in a structured language aims to guide web designers throughout the design process. The language has been implemented as an accessible rich Internet application itself, thus allowing designers with disabilities to participate in web design. In order to evaluate the design pattern language, a three-step process was carried out including: (1) a heuristic analysis with a group of human–computer interaction experts, (2) a survey study with a group of web designers, and (3) a validation on the field with two designers who have been requested to apply the language in real design cases.     

Aspects of nucleosomal positional flexibility and fluidity

Nucleosomes have been considered until recently to be stable and uniquely localized particles. We focus here on two properties of nucleosomes that are emerging as central attributes of their functions: mobility and multiplicity of localization. The biological relevance of these phenomena is based on the fact that chromatin functions depend on the relative stability of nucleosomes, on their covalent or conformational modifications, their dynamics, their localization, and the density of their distribution. In order to understand these complex behaviors both the structure of the nucleosome core particles and the informational rules governing their interaction with defined DNA sequences are here taken into consideration. The fact that nucleosomes solve the problem of how to locate a specific interaction site on a potentially infinite combination of sequences, with interactions recurring to a controlled level of informational ambiguity and stochasticity, is discussed. Nucleosomes have been shown to slide along DNA. This novel facet of their behavior and its implications in chromatin remodeling are reviewed.     

An analysis of XQuery benchmarks

This paper presents a survey and an analysis of the XQuery benchmark publicly available in 2006—XMach-1, XMark, X007, the Michigan benchmark, and XBench—from different perspectives. We address three simple questions about these benchmarks: How are they used? What do they measure? What can one learn from using them? One focus of our analysis is to determine whether the benchmarks can be used for micro-benchmarking. Our conclusions are based on an usage analysis, on an in-depth analysis of the benchmark queries, and on experiments run on four XQuery engines: Galax, SaxonB, Qizx/Open, and MonetDB/XQuery.     

Morphological and Biological Evaluations of Human Periodontal Ligament Fibroblasts in Contact with Different Bovine Bone Grafts Treated with Low-Temperature Deproteinisation Protocol

Several types of deproteinised bovine bone mineral (DBBM) are available on the market, and each one is obtained with a thermic and chemical process that can differ, achieving different results. Currently, several protocols using low temperature are suggested to reduce the possible particle crystallisation during the production process. This study aimed to evaluate the biomorphological reaction of periodontal fibroblast cultures in contact with different DBBM particles treated with a low-temperature protocol (Thermagen^®) and without exposure to sodium hydroxide (NaOH). Morphological evaluation was performed using light, confocal laser, and scanning electron microscopy, and the biological reaction in terms of proliferation was performed using an XTT proliferation assay at 24 h (T1), 72 h (T2), and 7 days (T3). The morphological analysis highlighted how the presence of the materials stimulated a change in the morphology of the cells into a polygonal shape, surface reactions with the thickening of the membrane, and expression of actin. In particular, the morphological changes were appreciable from T1, with a progressive increase in the considered morphological characteristics at T2 and T3 follow-ups. The proliferation assay showed a statistical significance between the different experimental materials and the negative control in T2 and T3 follow-ups. The post hoc analysis did not reveal any differences between the materials. In conclusion, the grafts obtained with the low-temperature extractions protocol and not exposed to NaOH solution showed positive morphological reactions with no differences in the sizes of particles.     

Putrescine: A Key Metabolite Involved in Plant Development,Tolerance and Resistance Responses to Stress

Putrescine (Put) is the starting point of the polyamines (PAs) pathway and the most common PA in higher plants. It is synthesized by two main pathways (from ornithine and arginine), but recently a third pathway from citrulline was reported in sesame plants. There is strong evidence that Put may play a crucial role not only in plant growth and development but also in the tolerance responses to the major stresses affecting crop production. The main strategies to investigate the involvement of PA in plant systems are based on the application of competitive inhibitors, exogenous PAs treatments, and the most efficient approaches based on mutant and transgenic plants. Thus, in this article, the recent advances in understanding the role of this metabolite in plant growth promotion and protection against abiotic and biotic stresses will be discussed to provide an overview for future research.     

Combination of freeze drying and molecular inclusion techniques improves the bioaccessibility of microencapsulated anthocyanins from black rice (Oryza sativa L.) and lavender (Lavandula angustifolia L.) essential oils in a model food system

Black rice and lavender are promising sources of bioactives, in terms of anthocyanins and essential oils. Their bioaccessibility were improved by microencapsulation, followed by mixing in order to benefit both from colour and flavour, along with radical scavenging and biological properties. The mixed powder showed a satisfactory anthocyanins of 2.55 mg g⁻¹ DW, leading to a radical scavenging activity of 65.14 mmol g⁻¹ DW. The powder displayed an inhibitory effect against α-glucosidase (~49%) and α-amylase (39%), respectively, with a controlled release in intestinal environment. To further examine the functional properties, the powder was added to a food model system. During storage, a release in anthocyanins and flavonoids were found, leading to an increase in radical scavenging activity. The sensorial analysis showed that supplemented biscuits were appreciated for colour and lavender aroma. The obtained results were promising in tailoring the health benefits of secondary metabolites, underutilised in human’s nutrition due to their low stability and bioavailability.     

Mutual Prodrugs of 5-Fluorouracil: From a Classic Chemotherapeutic Agent to Novel Potential Anticancer Drugs

The development of potent antitumor agents with a low toxicological profile against healthy cells is still one of the greatest challenges facing medicinal chemistry. In this context, the “mutual prodrug” approach has emerged as a potential tool to overcome undesirable physicochemical features and mitigate the side effects of approved drugs. Among broad-spectrum chemotherapeutics available for clinical use today, 5-fluorouracil (5-FU) is one of the most representative, also included in the World Health Organization model list of essential medicines. Unfortunately, severe side effects and drug resistance phenomena are still the primary limits and drawbacks in its clinical use. This review describes the progress made over the last ten years in developing 5-FU-based mutual prodrugs to improve the therapeutic profile and achieve targeted delivery to cancer tissues.     

A Kinetic Study on the Heat-Induced Changes of Whey Proteins Concentrate at Two pH Values

Whey protein concentrate (WPC) is used as food ingredients due to their commercially important functional properties. The effects of heat treatment on the components of milk are very important for the final product character, since they undergo modifications that affect sensorial and nutritional quality of milk. The heat-induced changes on dispersions of whey proteins concentrate were monitored by measurement of thiol availability, protein solubility, and turbidity at pH 6.6 and 7.5. The fractional conversion model was used to quantitatively describe the effect of different temperature–time combination on denaturation mechanism. The results demonstrate that heat-induced changes of WPC greatly influence their solubility, expressed as degree of denaturation at pH 4.6 and were related to the heating conditions. The denaturation mechanism involved a number of consecutive conformational changes in the molecules. A curvature in Arrhenius plots was observed around 75 °C, indicating changes in the reaction mechanism. The deflection of Arrhenius plot reflects the generally accepted two-step denaturation/aggregation process of whey proteins.