1,157 research outputs found
Phenomenological interpolation of the inclusive J/psi cross section to proton-proton collisions at 2.76 TeV and 5.5 TeV
We present a study of the inclusive J/psi cross section at 2.76 TeV and 5.5
TeV. The energy dependence of the cross section, rapidity and transverse
momentum distributions are evaluated phenomenologically. Their knowledge is
crucial as a reference for the interpretation of A-A and p-A J/psi results at
the LHC. Our approach is the following: first, we estimate the energy evolution
of the pt-integrated J/psi cross section at mid-rapidity; then, we evaluate the
rapidity dependence; finally, we study the transverse momentum distribution
trend. Whenever possible, both theory driven (based on pQCD predictions) and
functional form (data driven fits) calculations are discussed. Our predictions
are compared with the recently obtained results by the ALICE collaboration in
pp collisions at 2.76 TeV.Comment: 23 pages, 19 figures, updated text+figures, added comparison to ALICE
measurements at 2.76Te
Calcium silicate and calcium hydroxide materials for pulp capping: biointeractivity, porosity, solubility and bioactivity of current formulations
AIM:
The chemical-physical properties of novel and long-standing calcium silicate cements versus conventional pulp capping calcium hydroxide biomaterials were compared.
METHODS:
Calcium hydroxide-based (Calxyl, Dycal, Life, Lime-Lite) and calcium silicate-based (ProRoot MTA, MTA Angelus, MTA Plus, Biodentine, Tech Biosealer capping, TheraCal) biomaterials were examined. Calcium and hydroxyl ion release, water sorption, interconnected open pores, apparent porosity, solubility and apatite-forming ability in simulated body fluid were evaluated.
RESULTS:
All calcium silicate materials released more calcium. Tech Biosealer capping, MTA Plus gel and Biodentine showed the highest values of calcium release, while Lime-Lite the lowest. All the materials showed alkalizing activity except for Life and Lime-Lite. Calcium silicate materials showed high porosity values: Tech Biosealer capping, MTA Plus gel and MTA Angelus showed the highest values of porosity, water sorption and solubility, while TheraCal the lowest. The solubility of water-containing materials was higher and correlated with the liquid-to-powder ratio. Calcium phosphate (CaP) deposits were noted on materials surfaces after short aging times. Scant deposits were detected on Lime-Lite. A CaP coating composed of spherulites was detected on all calcium silicate materials and Dycal after 28 days. The thickness, continuity and Ca/P ratio differed markedly among the materials. MTA Plus showed the thickest coating, ProRoot MTA showed large spherulitic deposits, while TheraCal presented very small dense spherulites.
CONCLUSIONS:
calcium silicate-based cements are biointeractive (ion-releasing) bioactive (apatite-forming) functional biomaterials. The high rate of calcium release and the fast formation of apatite may well explain the role of calcium silicate biomaterials as scaffold to induce new dentin bridge formation and clinical healing
External root resorption management of an avulsed and reimplanted central incisor: A case report
Background: Avulsion and reimplantation of permanent teeth represent a major challenge in terms of treatment and long-term prognosis. The present study reported clinical management of external root resorption of an avulsed and reimplanted maxillary central incisor. Case report: A 9-year-old boy reported an uncomplicated crown fracture and avulsion of tooth 11 and complicated crown fracture of tooth 21 due to trauma. Reimplantation of element 11 was obtained within 30 min post-trauma and 3 days after both elements were diagnosed with necrotic pulp. In addition, tooth 11 showed early external root resorption. Both elements underwent endodontic treatment and root closure with apical plug using calcium-silicate-based cement. At 6-month follow-up root resorption appeared to be arrested. Twenty-four months after trauma the clinical results were stable, although signs and symptoms of ankylosis were observed. Conclusions: An immediate endodontic approach and use of calcium-silicate-based cement seemed to contrast the progression of root resorption of an avulsed and reimplanted central incisor after 24 months of follow-up
Different pulp dressing materials for the pulpotomy of primary teeth: A systematic review of the literature
Background: Pulpotomy of primary teeth provides favorable clinical results over time; however, to date, there is still not a consensus on an ideal pulp dressing material. Therefore, the aim of the present systematic review was to compare pulpotomy agents to establish a preferred material to use. Methods: After raising a PICO question, the PRISMA guideline was adopted to carry out an electronic search through the MEDLINE database to identify comparative studies on several pulp dressing agents, published up to October 2019. Results: The search resulted in 4274 records; after exclusion, a total of 41 papers were included in the present review. Mineral trioxide aggregate (MTA), Biodentine and ferric sulphate yielded good clinical results over time and might be safely used in the pulpotomies of primary molars. Among agents, MTA seemed to be the material of choice. On the contrary, calcium hydroxide showed the worst clinical performance. Although clinically successful, formocreosol should be replaced by other materials, due to its potential cytotoxicity and carcinogenicity. Conclusion: MTA seemed to be the gold standard material in the pulpotomy of primary teeth. Promising results were also provided by calcium silicate-based cements. Further randomized clinical trials (RCTs) with adequate sample sizes and long follow-ups are encouraged to support these outcomes
Bond strength of self-adhesive flowable composites and glass ionomer cements to primary teeth: A systematic review and meta-analysis of in vitro studies
Background: Conventional composites are largely used in pediatric restorative dentistry and demonstrate successful clinical outcomes. However, the need for simplification of operative steps in young or uncooperative children demands reliable alternatives. Therefore, the aim of the present systematic review and meta-analysis was to evaluate the in vitro bond strength of glass ionomer cements (GICs) and self-adhesive flowable composites (SFCs) on deciduous teeth. Methods: A comprehensive literature search according to the PRISMA checklist was manually and electronically performed by two independent reviewers through the following databases: MEDLINE/PubMed, Google Scholar, Scopus, and Embase, to include in vitro studies comparing GICs and SFCs bond strength values of restorations on primary teeth. In addition, three groups of meta-analyses were conducted using random-effects models. Results: Three articles meeting the inclusion criteria were selected and subjected to both qualitative and quantitative assessment. No statistically significant difference was found between SFC versus GIC; however, both groups significantly differed with conventional flowable composites (CFs). Conclusions: Despite the absence of significant difference in bond strength values, SFCs may be considered a valid alternative to GICs in the restoration of deciduous teeth, although CFs proved better in vitro performances
Cinética da adsorção de Cd, Co, Cr, Cu, K, Ni e Zn em soluçÔes aquosas usando zeólita natural integrada à tecnologia LTCC.
Materiais naturais, disponĂveis em grandes quantidades e que possam ser empregados como adsorventes de baixo custo para o tratamento de efluentes, vem sendo o alvo de inĂșmeras pesquisas. Quitosana, zeĂłlitas, esponjas naturais e carvĂŁo ativado sĂŁo empregados com sucesso para este propĂłsito1. Dentro deste contexto, o objetivo do trabalho foi investigar a capacidade de remoção de Cd, Co, Cr, Cu, K, Ni e Zn atravĂ©s de uma amostra de zeĂłlita natural integrada a dispositivos cerĂąmicos mediante a tecnologia LTCC
Prevalence, virulence and antimicrobial susceptibility of Salmonella spp., Yersinia enterocolitica and Listeria monocytogenes in european wild boar (Sus scrofa) hunted in Tuscany (central Italy)
Wild boar is an animal the population of which constantly increases in Europe. This animal plays an important role as a reservoir for several pathogens, including three of the most important zoonoses: salmonellosis, yersiniosis and listeriosis. The aim of this investigation was to eval-uate the occurrence of antimicrobial-resistant and virulence factor genes of Salmonella spp., Yersinia enterocolitica and Listeria monocytogenes isolated from wild boar in Tuscany (Central Italy). During two consequent hunting seasons (2018/2019 and 2019/2020), rectal swabs, spleens and livers were collected from 287 hunted wild boar to isolate strains. Each isolate was tested to investigate its an-timicrobial resistance and to detect virulence factor genes by PCR. Eighteen Salmonella strains (6.27%) were isolated. Of these, 66.7% were resistant to streptomycin, 13.4% to cephalothin, 6.67% to imipenem and one isolate (6.67%) was resistant simultaneously to five antimicrobials. Moreover, the most detected genes were sopE (73.4%), pipB (66.7%), sodCI (53.3%), spvR and spvC (46.7%). In total, 54 (17.8%) Yersinia enterocolitica were isolated; of them, 26 (48.1%), 9 (16.7%), 17 (31.5%), 1 (1.85%) and 1 (1.85%) belonged to biotypes 1, 2, 3, 4 and 5, respectively. All strains (100%) demon-strated resistance to cephalothin and 70.4% to amoxicillin-clavulanic acid, 55.6% to ampicillin, and 37.0% to cefoxitin. Additionally, the most detected genes were ystA (25.9%), inv (24.1%), ail (22.2%), ystB (18.5%) and virF (14.8%). Finally, only one Listeria monocytogenes isolate (0.35%) was obtained, belonging to serogroup IVb, serovar 4b, and it was found to be resistant to cefoxitin, cefotaxime and nalidixic acid. The results highlighted the role of wild boar as a carrier for pathogenic and antimi-crobial-resistant Salmonella spp., Yersinia enterocolitica and Listeria monocytogens, representing a possible reservoir for domestic animals and human pathogens
Presence and characterization of zoonotic bacterial pathogens in wild boar hunting dogs (Canis lupus familiaris) in tuscany (italy)
Domestic dogs (Canis lupus familiaris) used for wild boar (Sus scrofa) hunting may represent incidental hosts for several zoonotic pathogens. This investigation aimed to evaluate the presence of anti-Leptospira antibodies and the occurrence, antimicrobial resistance, and virulence of Salmonella spp., Yersinia enterocolitica, and Listeria monocytogenes in sera and rectal swabs collected from 42 domestic hunting dogs in the Tuscany region (Italy). Regarding Leptospira, 31 out of 42 serum samples (73.8%) were positive and serogroup Pomona was the most detected (71.4%) at titers between 1:100 and 1:400. Four Salmonella isolates (9.52%) were obtained, all belonging to serotype Infantis; two of them showed antimicrobial resistance to streptomycin, while pipB and sopE presence was assessed in all but one isolate. Concerning Yersinia enterocolitica, seven isolates (16.7%) were obtained, six belonging to biotype 1 and one to biotype 4. Resistance to amoxicillinâclavulanic acid, cephalothin, and ampicillin was detected. Biotype 4 presented three of the virulence genes searched (ystA, ystB, inv), while isolates of biotype 1 showed only one gene. No Listeria monocytogenes was isolated from dog rectal swabs. The results suggest that hunting dogs are exposed to different bacterial zoonotic agents, potentially linked to their work activity, and highlight the possible health risks for humans
Morpho-chemical observations of human deciduous teeth enamel in response to biomimetic toothpastes treatment
Today, biomaterial research on biomimetic mineralization strategies represents a new challenge in the prevention and cure of enamel mineral loss on delicate deciduous teeth. Distinctive assumptions about the origin, the growth, and the functionalization on the biomimetic materials have been recently proposed by scientific research studies in evaluating the different clinical aspects of treating the deciduous tooth. Therefore, appropriate morpho-chemical observations on delivering specific biomaterials to enamel teeth is the most important factor for controlling biomineralization processes. Detailed morpho-chemical investigations of the treated enamel layer using three commercial toothpastes (Biorepair, F1400, and F500) were performed through variable pressure scanning electron microscopy (VP-SEM) and energy dispersive X-ray spectroscopy (EDS) on deciduous teeth in their native state. A new microscopy methodology allowed us to determine the behaviors of silicate, phosphate, and calcium contents from the early stage, as commercially available toothpastes, to the final stage of delivered diffusion, occurring within the enamel layer together with their penetration depth properties. The reported results represent a valuable background towards full comprehension of the role of organic-inorganic biomaterials for developing a controlled biomimetic toothpaste in biofluid media
Kinetics of adsorption of Cd, Co, Cr, Cu, K, Ni and Zn in aqueous solutions using natural zeolite integrated to LTCC technology.
The LTCC technology (Low Temperature Co-fired Ceramics) has become much more versatile than any technique applied so far in the field of miniaturization, since allowing the construction of threedimensional devices quickly and easily. Due to the ease of handling, the green ceramic provide the multilayer arrangement of modules with different applications, such as, among others, in the field of microelectronics and manufacturing microvalves and microfluidic systems applied in flow injection systems. Natural materials, available in large quantities and that can be used as low cost adsorbents for wastewater treatment have been the target of numerous studies. As an example, chitosan, zeolites, natural sponges and activated carbon are used successfully for this purpose. Zeolites are natural or synthetic minerals, with a wide variety of technological applications. Its structure has channels and cavities in which it is possible to settle ions, water molecules or other adsorbates and salts. This study aimed to investigate the removal capacity of Cd, Cr, Cu, K, Ni and Zn by a sample of natural zeolite ceramic integrated devices through the LTCC technology. Ceramic systems with 2.6 cm long and 1.7 cm wide were constructed with natural zeolite integrated inside. The experimental parameters were optimized employing 10 mL of a 5 mg L-1 containing Cd, Co, Cr, Cu, K, Ni and Zn. The influence of pH and time on adsorption of metals by natural zeolite was evaluated. After the adsorption step solutions were analyzed by optical emission spectroscopy with inductively coupled plasma (ICP OES) for the analytes determination. The results showed that the determining factor in the adsorption capacity of natural zeolite is the pH of the solution. In the pH range of 6 up to 7 the competition adsorption of analytes was not observed. Values above 88% of adsorption were obtained for all metal ions studied. The kinetic study indicated that equilibrium was reached in approximately 2 hours of contact between the solution and natural zeolite. The results demonstrated the viability in the adsorption of Cd, Co, Cr, Cu, K, Ni and Zn in natural zeolite integrated ceramic systems, and the pH factor in optimizing the adsorption capacity of zeolite
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