Unseen science? Representation of BRICs in global science

A survey of scientific periodical publications (or venues-as distinct from articles) from BRIC country practitioners counted more than 15,000 national publications. Data collected from and about Brazil, Russia, India, and China (BRIC countries) show that 495 venues, or about 3%, are listed in the Science Citation Index Expanded^© (SCIE^©) in 2010. Contrary to our expectation of under-representation overall and coverage limitation of SCIE, the average percentage of SCIE-listed venues for the BRICs is about the same as that for advanced countries. China has the lowest representation of national venues in SCIE at 2% of all publications; Russia has the highest at about 8%. India has about 6% of venues in SCIE; Brazil has about 4%. In other words, SCIE includes about the same percentage of high quality science from these four countries as for North America and Europe, meaning that these countries are not under-represented in SCIE. Moreover, the number of national venues available as outlets suggests that national scientists in these countries have good access to publications and venues. Some of the BRIC national publications are difficult to “see” at the global level because of language barriers, diverse publication formats, and lack of digitization. Other national differences represent historical traditions surrounding publication.     

A new approach to network heterogeneity: Polymerization induced phase separation in photo-initiated,free-radical methacrylic systems

Non-reactive, thermoplastic prepolymers (poly- methyl, ethyl and butyl methacrylate) were added to a model homopolymer matrix composed of triethylene glycol dimethacrylate (TEGDMA) to form heterogeneous networks via polymerization induced phase separation (PIPS). PIPS creates networks with distinct phase structure that can partially compensate for volumetric shrinkage during polymerization through localized internal volume expansion. This investigation utilizes purely photo-initiated, free-radical systems, broadening the scope of applications for PIPS since these processing conditions have not been studied previously.The introduction of prepolymer into TEGDMA monomer resulted in stable, homogeneous monomer formulations, most of which underwent PIPS upon photo-irradiation, creating heterogeneous networks. During polymerization the presence of prepolymer enhanced autoacceleration, allowing for a more extensive ambient cure of the material. Phase separation, as characterized by dynamic changes in sample turbidity, was monitored simultaneously with monomer conversion and either preceded or was coincident with network gelation. Dynamic mechanical analysis shows a broadening of the tan delta peak and secondary peak formation, characteristic of phase-separated materials, indicating one phase rich in prepolymer and another depleted form upon phase separation. In certain cases, PIPS leads to an enhanced physical reduction of volumetric shrinkage, which is attractive for many applications including dental composite materials.     

Shelf life of powdered Campomanesia adamantium pulp in controlled environments

The objective of this study was to evaluate the shelf life of powdered guavira pulp obtained by a foam mat drying process. The dehydrated guavira pulp was packed into low density polyethylene (LDPE) bags and stored under two controlled conditions: environmental (25 °C, RH 75%) and accelerated (35 °C, RH 90%) for 90 days. The shelf life was accompanied by carrying out the following analyses every 10 days: moisture content, water activity, vitamin C content, pH and titratable acidity. Vitamin C was the quality attribute used to determine the shelf life of the product, by determining its degradation kinetics as a function of storage time. The linear regression data showed that the vitamin C degradation reaction fitted the zero and first order kinetic models. The shelf life of the powdered guavira pulp under environmental conditions was approximately 49 days, and under accelerated conditions (35 °C) 45 days. The Q10 was equal to 1.09, predicting a shelf life similar to that found under environmental conditions. The moisture content for these conditions was 10.0% e 5.4% for 35 °C and 25 °C, respectively. The above demonstrate the efficiency of the accelerated test in predicting the shelf life of the product.     

Microencapsulation of Propolis in Protein Matrix Using Spray Drying for Application in Food Systems

Propolis presents several health benefits due to the presence of bioactive compounds, mainly phenolic compounds; however, its application in food is limited due to undesirable odor and low water solubility. The bioactive compounds are usually susceptible to degradation by exposure to light, heat, or oxygen or by interaction with other compounds, which may limit its biological activity. The study aimed the propolis extract microencapsulation using rice, pea, soybean, and ovoalbumin proteins as wall material by spray drying and to analyze their in vitro digestion. The propolis extract presented a high concentration of apigenin. Encapsulation efficiency was greater than 70%, and it was maintained the antioxidant activity of propolis (88% inhibition of DPPH for propolis extract and >?73% for the microparticles). The DSC, ATR-FTIR, and X-ray diffraction techniques confirmed the encapsulation. The microparticles showed different shapes, sizes, and physical characteristics. The microparticles encapsulated with pea protein could be used in formulations of Minas Frescal cheese due to the controlled released, whereas the other microparticles could be used in pudding formulations.     

Fabrication of BSCF-based mixed oxide ionic-electronic conducting multi-layered membrane by sequential electrophoretic deposition process

The Ba_0.5Sr_0.5Co_0.8Fe_0.2O_3-δ (BSCF)-based multi-layered oxygen separation membrane was fabricated by the sequential electrophoretic deposition (EPD) process. A thin porous/dense bi-layer of BSCF was formed on a thick porous support of BSCF. The porous support prepared by a sacrificial template method using BSCF powder mixed with wheat starch (30 wt%) as a pore-forming agent, followed by uniaxial pressing and low-temperature sintering, was directly used as an EPD electrode. A thin BSCF layer was first formed on the porous support, and then a thin BSCF + PMMA (polymethyl methacrylate) layer was sequentially formed on the thin BSCF layer using a bimodal suspension of BSCF and PMMA. A 30-μm thin porous/dense bi-layer of BSCF of which the total thickness was obtained by optimizing the processes of EPD and subsequent co-sintering. The oxygen separation performance of 3.7 ml (STP) min^?1 cm^?2 at 860 °C was achieved for the BSCF-based multi-layered oxygen separation membrane.     

Theory as a source of software and system requirements

Requirements Engineering - Today, when undertaking requirements elicitation, engineers attend to the needs and wants of the user groups considered relevant for the software system. However, answers...     

Fluorescent Amino Acid Initiated de novo Cyclic Peptides for the Label-Free Assessment of Cell Permeability**

The major obstacle in applying peptides to intracellular targets is their low inherent cell permeability. Standard approaches to attach a fluorophore (e. g. FITC, TAMRA) can change the physicochemical properties of the parent peptide and influence their ability to penetrate and localize in cells. We report a label-free strategy for evaluating the cell permeability of cyclic peptide leads. Fluorescent tryptophan analogues 4-cyanotryptophan (4CNW) and β-(1-azulenyl)-L-alanine (AzAla) were incorporated into in vitro translated macrocyclic peptides by initiator reprogramming. We then demonstrate these efficient blue fluorescent emitters are good tools for monitoring peptide penetration into cells.     

Digital PCR Panel for Sensitive Hematopoietic Chimerism Quantification after Allogeneic Stem Cell Transplantation

Accurate and sensitive determination of hematopoietic chimerism is a crucial diagnostic measure after allogeneic stem cell transplantation to monitor engraftment and potentially residual disease. Short tandem repeat (STR) amplification, the current “gold standard” for chimerism assessment facilitates reliable accuracy, but is hampered by its limited sensitivity (≥1%). Digital PCR (dPCR) has been shown to combine exact quantification and high reproducibility over a very wide measurement range with excellent sensitivity (routinely ≤0.1%) and thus represents a promising alternative to STR analysis. We here aimed at developing a whole panel of digital-PCR based assays for routine diagnostic. To this end, we tested suitability of 52 deletion/insertion polymorphisms (DIPs) for duplex analysis in combination with either a reference gene or a Y-chromosome specific PCR. Twenty-nine DIPs with high power of discrimination and good performance were identified, optimized and technically validated. We tested the newly established assays on retrospective patient samples that were in parallel also measured by STR amplification and found excellent correlation. Finally, a screening plate for initial genotyping with DIP-specific duplex dPCR assays was designed for convenient assay selection. In conclusion, we have established a comprehensive dPCR system for precise and high-sensitivity measurement of hematopoietic chimerism, which should be highly useful for clinical routine diagnostics.     

Kernel density estimation based on Ripley’s correction

In this paper, we investigate a technique inspired by Ripley’s circumference method to correct bias of density estimation of edges (or frontiers) of regions. The idea of the method was theoretical and difficult to implement. We provide a simple technique – based of properties of Gaussian kernels – to efficiently compute weights to correct border bias on frontiers of the region of interest, with an automatic selection of an optimal radius for the method. We illustrate the use of that technique to visualize hot spots of car accidents and campsite locations, as well as location of bike thefts.