We build a theoretical model based on a generalization of harmonic applications of Misner-type. It results a sine-Gordon type fractal differential equation whose elliptical solutions can describe, through a convenient choice of fractal dynamic constants, various modes of drug release. Thus, the entire class of empirical models (Higuchi, Korsmeyer-Peppas, Peppas-Sahlin) describing the drug release processes can be dispensed with.
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It is known, as well as a rule, that plastic materials can not instictively and naturally degrade when released into the environment. Due to the persistence of plastics to degradation and also to propagation in industry, the problem of plastic pollution has progressed considerable in order to become a threat to global ecology, on land and sea. The present study presents a global mapping of actions brought in to reduce the use of plastic, plastic bags and foamed plastic products, followed by selected case studies from each region of the world, with more attention offered to the European Union countries and the strategies elaborated by them to provide a cleaner and safer environment.
The study aimed to highlight how unipodal stable equilibrium values are depending on the technical characteristics of plastic fitness equipment in relation to some anthropometric indices in order to optimize the physical potential. The best results recorded for the static balance test for both legs was on the Stability Disc, followed by Balance Board executions, and the weakest results were obtained on the Bosu Ball. The executions on the right leg were superior to executions on the left leg.
Negative pressure wound therapy is one of the newest methods of treatment used in wound healing. An important role of the system has a foam dressing that connects the wound with the vacuum. In general the sponge used in vacuum assisted therapies is made of polyurethane foam. We present the case of a 51-year-old male patient with a history of deep vein thrombosis (known for about 3 years) diagnosed with necrotizing fasciitis (NF). In this patient, after each step of the surgical treatment (large debridement and skin grafting) negative pressure wound therapy using polyurethane foam was used.
Flash-Free Orthodontic Adhesive System represents the latest technology in the field of orthodontics. In the present study the bonding technique is applied on CAD/CAM produced resin crowns. Ten resin blocks were shaped after an upper premolar crown design from the 3Shape Library, and they were divided ino two groups: on Group 1, control, Clarity Advanced braces (3M Unitek, Monrovia, CA, USA) were bonded using XT Adhesive Paste (3M Unitek, Monrovia, CA, USA), while on Groups 2 same aesthetic brackets were applied, using the APC Flash-Free Adhesive Coated Appliance System (3M Unitek, Monrovia, CA, USA). Bracket positioning time was recorded for each sample. Zwick Zoel Z005 testing machine was used to measure the shear bond strength (SBS) at which debonding takes place. Adhesive remnant index (ARI) was registered, as well as presence or absence of adhesive flash and accuracy of flash cleaning before curing. Group 1 showed a mean bonding time of 46.4 s, while Group 2 needed about 20.6 s for each bracket bonding. Mean SBS values for both groups are considered clinically acceptable (6.27 MPa for Group 1 and 7.77 MPa for Group 2). ARI scores were zero for all samples and after debonding, on group 1 can be observed the adhesive flash. In conclusion, APC Flash-Free Coated Appliance System showed reduced time for bracket positioning compared to the conventional technique. APC Flash-Free System showed acceptable SBS values, higher than the uncoated brackets. No composite was left on the resin crown after debonding, the adhesive flash resulted in the conventional technique remaining on the edges of the debonded brackets.
Many of the chemical additives in the plastic products, besides the possible safety problems that may arise during the production process, have negative effecty, too, on the environment and human health. Plastic is a synthetic polymer. The polymers include starch, latex and cellulose, combined with different substances and chemicals, used in various formulas, the polymer is included in the naylon. At high temperatures such as microwave oven temperature, polymers can migrate from the packaging plastic in food. In most cases, establishing the diagnosis of allergic disease is a complex and difficult operation. This difficulty is primarily related to the polymorphism of the clinical manifestations accompanying allergic reactions, the existence during the evolution of these conditions, of long clinical asymptomatic latencies, as well as due to numerous subjective and objective symptoms that overlap with those caused by the allergen, complicating and altering the clinical picture. Allergies are an abnormal reaction of the body to allergens and develop in two stages. After the first contact with the allergen, the IgE antibodies are produced, and the second contact produces the allergic reaction. The produced antibodies will release the chemical mediators (histamine, prostaglandine, etc.) which cause an inflammatory response, vascular changes and irritation of the tissues, with the appearance of symptoms specific to allergy: redness, rash, itching, edema, etc.The so complex symptom of allergic diseases comprises several systems and organs at the same time, and the existence of over-additive phenomena makes it impossible to have characteristic clinical symptoms of allergic diseases that allow their identification only by clinical examination. However, this does not mean that the clinical exam and the analysis of the various objective and subjective symptoms presented by the patient is of no importance in establishing the diagnosis and recognizing the allergic character of the disease.The study includes a number of patients studied at the Galati Allergy Clinic. Specific immunotherapy known as desensitization or anti-allergic vaccination, is designed to fight the causes of allergies that occur when the immune system misinterprets harmless substances. Clinical examination results are complemented by allergen and specific antibody research; skin tests are the most common method for allergen detection.
The development of antibiotic resistance in bacteria possesses a huge threat to public health by nullifying the effect of even the most efficient antibiotics. From years, LDHs type nanomaterials have been used as drug carriers for a wide variety of pharmaceutically active molecules due to their delivery properties, making these inorganic-organic nanohybrids very efficient antimicrobial agents. The major purpose of this work was to synthesize and characterize ceftriaxone intercalated layered nanostructures for further use to treat some infections, mostly of them child infections. The novel nanohybrid materials were prepared by ion exchange route and coprecipitation method. Structural and morphological characterization was performed by FTIR, EDX and SEM techniques. The results revealed a high incorporation of the drug in the interlayer space of promising nanostructures.
The present paper is focused on analyzing if appropriate adhesion between the polymeric matrix and titania filler nanoparticles is obtained for the PMMA-TiO2 photo-curable dental material, suitable for application in RP - stereolithography (SLA) for complete denture manufacturing. It was found that different amounts, between 0.2% and 2.5 % (w/w%), of added titanium oxide nanoparticles slightly modify the structural behavior of the PMMA polymeric matrix. The material characterization was carried out using FT-IR and microscopy techniques.
Using nanotechnology to produce composite materials it has been possible to obtain materials with similar or better mechanical properties than previous generation of microhybrids, and with exceptional aesthetics and chandelier due to the particularities of nanomaterials. At the same time, the improvement of adhesive techniques to enamel and dentin allowed the expansion of the area of direct composite restorations with a better prognostic over time.Eight carie-free molars were used and each of them was prepared with two class II cavities, which were filled using the C13 and C20 nanocomposites and the A1 and A2 experimental adhesive systems prepared at the Raluca Ripan Chemistry Research Institute. The teeth were divided into four groups of two teeth each, depending on the adhesive system and the composite material used. Scanning electron microscopy images (SEM) have described the adhesive interface and structure characteristics for the two nanocomposite materials and for the two studied adhesive systems.The studied nanocomposites have a variable number of porosities and air bubbles, with a clinical importance which is yet hard to establish.The experimental adhesives used produce a good interface and infiltration of the smear-layer but have not been visualized inside the dentinal canals.In vitro studies are necessary to evaluate the durability of adhesion in the case of self-etch adhesives in one or two steps.
The species from the increased biofouling on the paint layers applied to the metallic strength structure of a railway bridge located in a Natura 2000 protected area have been identified by specific biologic and microbiological methods. As a result of the analysis of the biological samples taken on the field, it has been found that relatively large variety of filamentous molds are present (Aspergillus fumigatus, Asprgillus flavus, Aspergillus niger, Paecilomyces variotii, Chaetomium globosum, Trichoderma viride, Stachybotris atra, Trichoderma sp., Alternaria sp and Penicillium sp.). Samples also show, lichens (Xanthoria parietina and Hypogymnia physodes) and lower plants capable of photosynthesis such as algae (Chlorophyta Xanthophyceae, Chrysophyceae) and moss (Lunularia cruciata, Marchantiophyta).