934 research outputs found

    Measuring the accuracy of software vulnerability assessments: experiments with students and professionals

    Get PDF
    Assessing the risks of software vulnerabilities is a key process of software development and security management. This assessment requires to consider multiple factors (technical features, operational environment, involved assets, status of the vulnerability lifecycle, etc.) and may depend from the assessor's knowledge and skills. In this work, we tackle with an important part of this problem by measuring the accuracy of technical vulnerability assessments by assessors with dierent level and type of knowledge. We report an experiment to compare how accurately students with dierent technical education and security professionals are able to assess the severity of software vulnerabilities with the Common Vulnerability Scoring System (v3) industry methodology. Our results could be useful for increasing awareness about the intrinsic subtleties of vulnerability risk assessment and possibly better compliance with regulations. With respect to academic education, professional training and human resources selections our work suggests that measuring the effects of knowledge and expertise on the accuracy of software security assessments is feasible albeit not easy

    Survival rate of indirectly bonded brackets using single vs. two-component orthodontic adhesive: A 12-month split-mouth clinical trial

    Get PDF
    Objective: Compare the bonding survival rate of two distinct bonding materials: Ortho Solo + Gradia LoFlo Resin and single component GC Ortho Connect. Materials and Methods: Indirect bonding fixed appliance treatment was required for 26 consecutive patients, 8 males and 18 females, with a mean age of 22.1 +/- 4.2 years. All patients were treated with SWM (Straight-Wire Mirabella) technique (Sweden and Martina, Due Carrare, Padova, Italy). Each patient's bonding process followed a contralateral pattern. Firstly, a 37 % orthophosphoric acid etching gel was used for 20 s, subsequently the single or two components light-cured adhesives were applied through a split-mouth cross-arch procedure. The patients underwent a 12-month follow-up period and brackets failures were rebounded, but not further included in the study. Statistical analysis was performed to analyse the survival rate of the bonding materials and the influence of the variables, with a significant level of α = 0,05. Results: The GC Connect group was used on 349 teeth, while the Ortho Solo + Gradia group was used on 351 teeth, and the indirect debonding rate was respectively 17.5% and 12.8%. With respect to the total sample, statistically significant values were found for both sex and dental arch. The bracket's survival rate for incisors, canines, premolars and molars was not significant. However, a higher debonding rate was clinically appreciable in upper and lower molars. Conclusion: In a 12-months observation period, considering all maxillary and mandibular teeth the indirect survival rate for the group GC Ortho Connect and Ortho Solo + Gradia was respectively 82.5% and 87.2%. Although the difference was not significant, a pronounced tendency to debonding for the single component group was appreciable from a clinically point of view

    Palatal skeletal anchorage: multiple applications with a single appliance

    Get PDF
    Using a single bone-borne maxillary appliance with twofold mechanics, that is, rapid palatal expander and nonfrictional distalizing appliance (Pendulum) is a valuable option to treat young-adult patients with poor compliance. In this particular case, the same appliance was used to disinclude 2.3, eliminating reaction forces on the arch. Therefore, the first expansive phase was followed by the distalizing phase. After enough space was obtained for the recovery of tooth 2.3, a triple-looped titanium-molybdenum alloy (TMA) spring was used to perform canine orthodontic traction. The core concept is that digital planning and optimal positioning of two palatal mini-screws can ensure a bicortical anchorage which, in turn, enabled to tolerate the different orthodontic phases. As a matter of fact, a tooth-bone-borne anchorage was followed by a pure bone-borne anchorage with no lost of stability

    Drug Screening in Human Cells by NMR Spectroscopy Allows the Early Assessment of Drug Potency

    Get PDF
    Structure-based drug development is often hampered by the lack of in vivo activity of promising compounds screened in vitro, due to low membrane permeability or poor intracellular binding selectivity. Herein, we show that ligand screening can be performed in living human cells by “intracellular protein-observed” NMR spectroscopy, without requiring enzymatic activity measurements or other cellular assays. Quantitative binding information is obtained by fast, inexpensive 1H NMR experiments, providing intracellular dose- and time-dependent ligand binding curves, from which kinetic and thermodynamic parameters linked to cell permeability and binding affinity and selectivity are obtained. The approach was applied to carbonic anhydrase and, in principle, can be extended to any NMR-observable intracellular target. The results obtained are directly related to the potency of candidate drugs, that is, the required dose. The application of this approach at an early stage of the drug design pipeline could greatly increase the low success rate of modern drug development

    Anthocyanins inhibit tumor necrosis alpha-induced loss of Caco-2 cell barrier integrity

    Get PDF
    An increased permeability of the intestinal barrier is proposed as a major event in the pathophysiology of conditions characterized by chronic gut inflammation. This study investigated the capacity of pure anthocyanins (AC), and berry and rice extracts containing different types and amounts of AC, to inhibit tumor necrosis alpha (TNFα)-induced permeabilization of Caco-2 cell monolayers. Caco-2 cells differentiated into intestinal epithelial cell monolayers were incubated in the absence/presence of TNFα, with or without the addition of AC or AC-rich plant extracts (ACRE). AC and ACRE inhibited TNFα-induced loss of monolayer permeability as assessed by changes in transepithelial electrical resistance (TEER) and paracellular transport of FITC-dextran. In the range of concentrations tested (0.25–1 ÎŒM), O-glucosides of cyanidin, and delphinidin, but not those of malvidin, peonidin and petunidin protected the monolayer from TNFα-induced decrease of TEER and increase of FITC-dextran permeability. Cyanidin and delphinidin acted by mitigating TNFα-triggered activation of transcription factor NF-ÎșB, and downstream phosphorylation of myosin light chain (MLC). The protective actions of the ACRE on TNFα-induced TEER increase was positively correlated with the sum of cyanidins and delphinidins (r2 = 0.83) content in the ACRE. However, no correlation was observed between TEER and ACRE total AC, malvidin, or peonidin content. Results support a particular capacity of cyanidins and delphinidins in the protection of the intestinal barrier against inflammation-induced permeabilization, in part through the inhibition of the NF-ÎșB pathway.Fil: Cremonini, Eleonora. University of California at Davis; Estados UnidosFil: Mastaloudis, Angela. Nu Skin Enterprises; Estados UnidosFil: Hester, Shelly N.. Nu Skin Enterprises; Estados UnidosFil: Verstraeten, Sandra Viviana. Universidad de Buenos Aires. Facultad de Farmacia y BioquĂ­mica. Departamento de QuĂ­mica BiolĂłgica; Argentina. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Houssay. Instituto de QuĂ­mica y FĂ­sico-QuĂ­mica BiolĂłgicas "Prof. Alejandro C. Paladini". Universidad de Buenos Aires. Facultad de Farmacia y BioquĂ­mica. Instituto de QuĂ­mica y FĂ­sico-QuĂ­mica BiolĂłgicas; ArgentinaFil: Anderson, Maureen. University of California at Davis; Estados UnidosFil: Wood, Steven M.. Nu Skin Enterprises; Estados UnidosFil: Waterhouse, Andrew L.. University of California at Davis; Estados UnidosFil: Fraga, CĂ©sar Guillermo. University of California at Davis; Estados Unidos. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Houssay. Instituto de BioquĂ­mica y Medicina Molecular. Universidad de Buenos Aires. Facultad de Farmacia y BioquĂ­mica. Instituto de BioquĂ­mica y Medicina Molecular; ArgentinaFil: Oteiza, Patricia Isabel. University of California at Davis; Estados Unidos. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas; Argentin

    Impact of TiO2 nanoparticles on Vicia narbonensis L.: potential toxicity effects

    Get PDF
    This work was aimed to provide further information about toxicology of TiO2 nanoparticles (NPs) on Vicia narbonensis L., considering different endpoints. After exposure to TiO2 nanoparticle suspension (mixture of rutile and anatase, size <100 nm) at four different concentrations (0.2, 1.0, 2.0 and 4.0 ‰), the seeds of V. narbonensis were let to germinate in controlled environmental conditions. After 72 h, the extent of the success of the whole process (seed germination plus root elongation) was recorded as the vigour index, an indicator of possible phytotoxicity. After the characterisation of the hydric state of different materials, oxidative stress and enzymatic and nonenzymatic antioxidant responses were considered as indicators of possible cytotoxicity and to assess if damage induced by TiO2 NPs was oxidative stress-dependent. Cytohistochemical detection of in situ DNA fragmentation as genotoxicity endpoint was monitored by TUNEL reaction. The treatments with TiO2 NPs in our system induced phytotoxic effects, ROS production and DNA fragmentation. The nonenzymatic and enzymatic antioxidant responses were gradually and differentially activated and were able to maintain the oxidative damage to levels not significantly different from the control. On the other hand, the results of DNA fragmentation suggested that the mechanisms of DNA repair were not effective enough to eliminate early genotoxicity effects

    The asymmetric diffusion of trust between communities: simulations in dynamic social networks

    Get PDF
    In this work, we present a model of social network showing non-trivial effects on the dynamics of trust and communication. Our model's results meet the characteristics of a typical social network, such as the limited node degree, assortativeness, clustering and communities formation. Simulations have been run first to present some of the most fundamental relations among the main model's attributes. Next, we focused on the emerging asymmetry with which trust develops within different communities in a network. In particular, we considered categories of nodes differing for their communication profiles and a specific example of bridge between two communities. The results are discussed to provide insights about the dynamic formation of communities based on trust relations. These results are the basis for future works with the aim of better understanding the dynamics of the diffusion of trust and its influence on a growing social network

    The use of sodium bicarbonate for marination of broiler breast meat

    Get PDF
    This study aimed at evaluating marination performances and effect on meat quality traits of sodium bicarbonate, used alone or in combination with sodium chloride, when compared with sodium trypolyphosphate by using advanced analytical tools including low-field nuclear magnetic resonance (LF-NMR) and differential scanning calorimetry (DSC). A total of 140 samples (cylindrical shape of 1×4 cm size) were obtained from a batch of 24h post mortem broiler breast meat (Ross 708, females, 47 day-old). Six of the groups were used for subsequent marination treatments, while the last group was kept as non-marinated control (C). Samples were subjected to vacuum tumbling in a special equipped laboratory rotary evaporator with a 12% (w/w) water:meat ratio using 6 marinade solutions: 7.7% (w/w) NaCl (S); 2.3% Na4O7P2 (w/w) (P); 2.3% (w/w) NaHCO3 (B); 7.7% (w/w) NaCl and 2.3% Na4O7P2 (w/w) (SP); 7.7% (w/w) NaCl and 2.3% (w/w) NaHCO3 (SB); 7.7% (w/w) NaCl, 2.3% Na4O7P2 (w/w) and 2.3% (w/w) NaHCO3 (SPB). Samples marinated with bicarbonate alone or in combination (B, SB and SPB) significantly increased (P<0.05) meat pH by approximately 0.7 units compared to the control, whilst phosphate alone or in combination with salt increased (P<0.05) the pH by 0.2 units. Combination containing all ingredients (SPB) produced the highest marinade performances, however sodium bicarbonate with salt (SB) was able to guarantee a better marinade uptake and water retention ability in respect to phosphates (SP). According to LR-NMR, the combined use of bicarbonate and/or phosphate with sodium chloride determined a remarkable increase of proportion of entrapped water into myofibrillar spaces, while extra-myofibrillar water fraction was not modified. Moreover water gain following marination does not correspond to an increase of freezable water amount as detected by DSC. In conclusion, bicarbonate is a very promising marinating agent and it can be exploited to develop processed poultry products with no added phosphates in order to match the request to avoid the nutritional drawbacks recently indicated with the use of phosphates
    • 

    corecore