Nanotag luminescent fingerprint anti-counterfeiting technology

ABSTRACT: We describe a method to fabricate, transfer and validate via image processing nanofibre-based, unique security marks ('nanotags') for anti-counterfeiting purposes. Epitaxial surface growth of oligophenylenes on a heated muscovite mica crystal results in a thin film of mutually aligned nanofibres with dimensions of tens of nanometres in height, hundreds of nanometres in width and tens to hundreds of micrometres in length. By applying a shadow mask, a film pattern is generated which contains only sparse, randomly grown nanofibres, which in turn represent a unique 'fingerprint' of the growth area. This fingerprint can be transferred on an adhesive tape as a label of a product, imaged using low magnification microscopy, digitalised and stored in a database. Infrared surface heating, enforced cooling and load lock transfer makes the fabrication process fast and scalable to mass production.     

Common Fragile Sites: Genomic Hotspots of DNA Damage and Carcinogenesis

Genomic instability, a hallmark of cancer, occurs preferentially at specific genomic regions known as common fragile sites (CFSs). CFSs are evolutionarily conserved and late replicating regions with AT-rich sequences, and CFS instability is correlated with cancer. In the last decade, much progress has been made toward understanding the mechanisms of chromosomal instability at CFSs. However, despite tremendous efforts, identifying a cancer-associated CFS gene (CACG) remains a challenge and little is known about the function of CACGs at most CFS loci. Recent studies of FATS (for Fragile-site Associated Tumor Suppressor), a new CACG at FRA10F, reveal an active role of this CACG in regulating DNA damage checkpoints and suppressing tumorigenesis. The identification of FATS may inspire more discoveries of other uncharacterized CACGs. Further elucidation of the biological functions and clinical significance of CACGs may be exploited for cancer biomarkers and therapeutic benefits.     

Predicting diffuse illuminance on vertical surfaces at Arcavacata di Rende (Italy) for various types of sky

The diffuse natural illuminance of variously oriented vertical surfaces was calculated by nine models under various sky conditions, subdividing the experimental data into eight types of sky, on the basis of the value of the Perez sky clearness index parameter. The calculated data were compared with the experimental data measured over a complete year at Arcavacata di Rende (Italy) (latitude 39°21′N, longitude 16°13′E).     

The practice of ring constraint in peptidomimetics using bicyclic and polycyclic amino acids

Medicinal chemistry has witnessed major advances with the discovery of small synthetic molecules that mimic natural peptidic substrates. These small synthetic mimics do not undergo proteolytic degradation, an advantage they hold over their natural counterparts. Small synthetic molecules make up a number of life-saving marketed drugs that inhibit certain physiologically relevant proteases. The advent of sophisticated instrumental methods, such as X-ray crystallography and high-field NMR, has played a pivotal role in the design of structure-based enzyme inhibitors. Highly stereocontrolled methods of synthesis have led to a variety of functionally diverse molecules that function as peptidomimetics because they have isosteric subunits not affected by proteolytic enzymes. Further studies to optimize biological activity and achieve desirable pharmacokinetic profiles can eventually lead to drug substances. The practice of constraining natural amino acids like their conformationally rigid counterparts has been highly successful in the design and synthesis of peptidomimetic molecules. With some notable exceptions, structural information gathered from protein X-ray crystallography of therapeutically relevant target enzymes, alone or in complex forms with inhibitor molecules, has been instrumental in the design of peptidomimetics. For example, a significant number have become marketed drugs as antihypertensives and antivirals. Natural products have also been a source of inspiration for the design and synthesis of truncated analogues with the intention of maintaining, or even improving, their biological activities. However, lower molecular weight peptides are not suitable as therapeutic agents because they are subject to rapid amide proteolysis. They are poorly transported to the brain and rapidly excreted through the liver and kidney. Thus, lower molecular weight peptides are eliminated as potential drug substances in clinical practice. A synthetic peptidomimetic is needed that is resistant to cleavage but maintains its biological activity. Conformationally constrained monocyclic and bicyclic unnatural amino acids can be directly incorporated in a potential inhibitor molecule as part of the design element. In this Account, we describe our efforts in the synthesis of constrained azacycles that contain proline or pipecolic acid as an integral part of bicyclic and polycyclic amino acids. We devised syntheses of conformationally biased monocyclic, bicyclic, and polycyclic amino acid analogues, into which pharmacologically or structurally relevant functional groups were incorporated. Stereocontrolled reactions for C-C, C-N, and C-O bond formation had to be implemented on appropriately protected amino acid frameworks. A number of these frameworks provided access to functionally diverse scaffolds for further use as core subunits in more elaborated structures. Specific applications as peptidomimetics of natural substrates for relevant enzymes, such as thrombin, were also pursued, resulting in highly active inhibitors in vitro.     

Effects of season, milking routine and cow cleanliness on bacterial and somatic cell counts of bulk tank milk

The aim of the study was to investigate the effects of season, cow cleanliness and milking routine on bacterial and somatic cell counts of bulk tank milk. A total of 22 dairy farms in Lombardy (Italy) were visited three times in a year in different seasons. During each visit, samples of bulk tank milk were taken for bacterial and somatic cell counts; swabs from the teat surface of a group of cows were collected after teat cleaning and before milking. Cow cleanliness was assessed by scoring udder, flanks and legs of all milking cows using a 4-point scale system. Season affected cow cleanliness with a significantly higher percentage of non-clean (NC) cows during Cold compared with Mild season. Standard plate count (SPC), laboratory pasteurization count (LPC), coliform count (CC) and somatic cell count, expressed as linear score (LS), in milk significantly increased in Hot compared with Cold season. Coagulase-positive staphylococci on teat swabs showed higher counts in Cold season in comparison with the other ones. The effect of cow cleanliness was significant for SPC, psychrotrophic bacterial count (PBC), CC and Escherichia coli in bulk tank milk. Somatic cell count showed a relationship with udder hygiene score. Milking operation routine strongly affected bacterial counts and LS of bulk tank milk: farms that accomplished a comprehensive milking scheme including two or more operations among forestripping, pre-dipping and post-dipping had lower teat contamination and lower milk SPC, PBC, LPC, CC and LS than farms that did not carry out any operation.     

Quality control of Toxoplasma gondii in meat packages: standardization of an ELISA test and its use for detection in rabbit meat cuts

Toxoplasma gondii causes severe disease both to man and livestock and its detection in meat after slaughtering requires PCR or biological tests. Meat packages contain retained exudate that could be used for serology due to its blood content. Similar studies reported false negative assays in those tests. We standardized an anti-T. gondii IgG ELISA in muscle juices from experimentally infected rabbits, with blood content determination by cyanhemoglobin spectrophotometry. IgG titers and immunoblotting profiles were similar in blood, serum or meat juice, after blood content correction. These assays were adequate regardless of the storage time up to 120 days or freeze-thaw cycles, without false negative results. We also found 1.35% (1/74) positive sample in commercial Brazilian rabbit meat cuts, by this assay. The blood content determination shows ELISA of meat juice may be useful for quality control for toxoplasmosis monitoring.     

Antimicrobial resistance in Salmonella enteritidis strains isolated from broiler carcasses, food, human and poultry-related samples

Antimicrobial resistance was investigated in 91 Salmonella enteritidis isolates from broiler carcasses, food, human and poultry-related samples originated from South of Brazil. A great proportion of resistant strains was found, 90.1% showing resistance to at least one antimicrobial drug. There was a high resistance to sulfonamides (75.8%) and nitrofurantoin (52.8%). Lower levels of resistance were found for tetracycline (15.4%), streptomycin (7.7%), nalidixic acid (7.7%), gentamicin (5.5%), norfloxacin (3.3%), trimethoprim (3.3%), cefalotin (2.2%), ampicillin (1.1%), and chloramphenicol (1.1%). Resistance to ciprofloxacin was not detected. A total of 51.6% of S. enteritidis strains were multiresistant (resistance to two or more antimicrobial agents) and 18 resistance patterns were found. The highest resistance was found in strains isolated from poultry-related samples, where all strains were resistant to at least one antimicrobial agent. No predominant resistance pattern was related to phage type in our isolates. The high number of antimicrobial resistant S. enteritidis found in Southern Brazil indicates the need for the prudent drugs uses to diminish the development and spread of antimicrobial resistance.     

Glass transition improvement in epoxy/graphene composites

Graphene oxide nanoplatelets (GO) were prepared from expanded graphite (EG) and functionalized with triethylenetetramine (GO-TETA). The GO-TETA consisted of a few layers of graphene (~4–6 layers), as determined by atomic force microscopy and Raman spectroscopy. X-ray photoelectron spectroscopy showed that the TETA was covalently linked to the GO in the GO-TETA sample. Epoxy composites based on the diglycidyl ether of bisphenol A with TETA as a hardener and with 0.5–3.0 wt% additions of EG and GO-TETA were investigated. The results showed that the addition of the nanofillers led to an increase of ~20 °C in the glass transition temperature. A slight increase in the ratio of the elastic modulus/hardness of the nanocomposites was observed by nanoindentation tests carried out at a depth range of 300 nm–1.3 μm; these tests indicated a tendency of increased fracture toughness. Microindentation had an enhancement of 40 % in hardness for the 1 wt% composite with GO-TETA relative to the corresponding value for the neat epoxy.     

Economic feasibility of adopting a hydroponics system on substrate in small rural properties

Clean Technologies and Environmental Policy - Objective is to analyze the economic feasibility of implementing a greenhouse in a hydroponics production system in substrate (sand) on a small family...