156 research outputs found

    Room temperature co-precipitation synthesis of magnetite nanoparticles in a large pH window with different bases

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    pre-printMagnetite nanoparticles (Fe3O4) represent the most promising materials in medical applications. To favor high-drug or enzyme loading on the nanoparticles, they are incorporated into mesoporous materials to form a hybrid support with the consequent reduction of magnetization saturation. The direct synthesis of mesoporous structures appears to be of interest. To this end, magnetite nanoparticles have been synthesized using a one pot co-precipitation reaction at room temperature in the presence of different bases, such as NaOH, KOH or (C2H5)4NOH. Magnetite shows characteristics of superparamagnetism at room temperature and a saturation magnetization (Ms) value depending on both the crystal size and the degree of agglomeration of individual nanoparticles. Such agglomeration appears to be responsible for the formation of mesoporous structures, which are affected by the pH, the nature of alkali, the slow or fast addition of alkaline solution and the drying modality of synthesized powders

    Leveraging Mobility Flows from Location Technology Platforms to Test Crime Pattern Theory in Large Cities

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    Crime has been previously explained by social characteristics of the residential population and, as stipulated by crime pattern theory, might also be linked to human movements of non-residential visitors. Yet a full empirical validation of the latter is lacking. The prime reason is that prior studies are limited to aggregated statistics of human visitors rather than mobility flows and, because of that, neglect the temporal dynamics of individual human movements. As a remedy, we provide the first work which studies the ability of granular human mobility in describing and predicting crime concentrations at an hourly scale. For this purpose, we propose the use of data from location technology platforms. This type of data allows us to trace individual transitions and, therefore, we succeed in distinguishing different mobility flows that (i) are incoming or outgoing from a neighborhood, (ii) remain within it, or (iii) refer to transitions where people only pass through the neighborhood. Our evaluation infers mobility flows by leveraging an anonymized dataset from Foursquare that includes almost 14.8 million consecutive check-ins in three major U.S. cities. According to our empirical results, mobility flows are significantly and positively linked to crime. These findings advance our theoretical understanding, as they provide confirmatory evidence for crime pattern theory. Furthermore, our novel use of digital location services data proves to be an effective tool for crime forecasting. It also offers unprecedented granularity when studying the connection between human mobility and crime

    Experimental Evidence of the Effectiveness and Applicability of Colloidal Nanosilica Grouting for Liquefaction Mitigation

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    AbstractThe low viscosity and the ability to control solidification rate make colloidal nanosilica grout an excellent ground-improvement solution which is functional for different engineering purpo..

    Late diagnosis of celiac disease in an asymptomatic infant with growth failure

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    The clinical spectrum for celiac disease (CD) is broad and includes cases with either typical (intestinal) or atypical (extraintestinal) features, often making the diagnosis of CD very difficult. We describe the case of a girl presenting with stunted growth and malnourishment. She was evaluated at 14 months for decreased growth rate without any signs of gastrointestinal, renal or endocrine disorders. She was evaluated for CD, but resulted negative for anti-tTG antibodies. At the age of 4.1 years, she exhibited basal dental enamel hypoplasia, iron deficiency anaemia despite repeated iron supplementation, with persistent reduced height (-2.79 SDS), BMI (-0.76 SDS), growth velocity (-1.79 SDS) and delayed bone age (1.5 year). The CD screening was repeated and very high anti-tTG-IgA (128 IU/ml, normal values 40 IELs/100 epithelial cells) confirming the diagnosis of CD. A gluten-free diet was started and after only four months, her growth velocity increased from 4.83 cm/year (-1.79 SDS) to 6.53 cm/year (-0.15 SDS). In conclusion, we report the development of a positive serology for CD in an asymptomatic child with growth retardation, who previously was investigated for CD and resulted negative. Therefore, when faced with retarded growth in young patients, after excluding other malabsorption conditions and even when CD serological markers are negative, the paediatric endocrinologist should request HLA genotyping, before the intestinal biopsy, in order to check for the presence of risk alleles

    Strength of sandy and clayey soils cemented with single and double fluid jet grouting

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    Abstract Innovations in jet grouting technology have primarily focused on the cutting efficiency of the jets, with the aim of creating larger columns and increasing the productivity of construction sites. Relatively little attention has been paid to the consequences of the grouting system on the mechanical properties of the formed material. This paper investigates this aspect by analysing the results of two field trials carried out in both sandy and clayey soils, where single and double fluid jet grouting were simultaneously performed, with varied grout composition and injection parameters. Parallel uniaxial compressive tests on samples cored from the columns show that the material formed with the double system is systematically lower in strength than the material formed using the single fluid system. The mineralogical composition of samples cored from the columns was analysed by performing parallel Scanning Electron Microscopy (SEM), X-ray diffraction analysis (XRD), Differential Thermal Analysis (DTA) and Thermo-Gravimetric Analyses (TGA) to determine the reasons for this difference. A lower proportion of cementitious products, an accelerated carbonation of portlandite and a less homogeneous distribution of cement hydration products was found on the surface of the soil particles of the double samples than for the single fluid columns

    Preventable Cases of Oral Anticoagulant-Induced Bleeding: Data From the Spontaneous Reporting System

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    Background: Despite the risk of bleeding is a well-known adverse effect of oral anticoagulants, there is scarce evidence on the preventability of oral anticoagulant-induced bleedings. Therefore, we investigated the potential risk factors related to preventable cases of oral anticoagulant-induced bleedings. Methods: We performed a study using Individual Case Safety Reports (ICSRs) with an oral anticoagulant as suspected drug among those reported through the spontaneous reporting system of Campania Region from 1 July 2012 to 31 December 2017. The P-method was used for the preventability assessment of all cases of bleeding. Results: In total, 58 cases out of 253 (22.9%) were preventable, and the most reported suspected drug was an indirect oral anticoagulant (warfarin). Sixty-eight critical criteria for preventability were identified, all related to healthcare professionals' practices. The most detected risk factor related to healthcare professionals' practices was the labeled drug-drug interaction for both direct and indirect oral anticoagulants. Conclusion: Our findings describe the most reported risk factors for preventability of oral anticoagulant-induced bleedings. These factors may be useful for targeting interventions to improve pharmacovigilance activities in our regional territory and to reduce the burden of medication errors and inappropriate prescription

    The New Paradigms in Clinical Research: From Early Access Programs to the Novel Therapeutic Approaches for Unmet Medical Needs

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    Despite several innovative medicines gaining worldwide approval in recent years, there are still therapeutic areas for which unsatisfied therapeutic needs persist. For example, high unmet clinical need was observed in patients diagnosed with type 2 diabetes mellitus and hemophilia, as well as in specific age groups, such as the pediatric population. Given the urgent need to improve the therapy of clinical conditions for which unmet clinical need is established, clinical testing, and approval of new medicines are increasingly being carried out through accelerated authorization procedures. Starting from 1992, the Food and Drug Administration and the European Medicines Agency have supported the so-called Early Access Programs (EAPs). Such procedures, which can be based on incomplete clinical data, allow an accelerated marketing authorization for innovative medicines. The growth in pharmaceutical research has also resulted in the development of novel therapeutic approaches, such as biotech drugs and advanced therapy medicinal products, including new monoclonal antibodies for the treatment of asthma, antisense oligonucleotides for the treatment of Duchenne muscular dystrophy and spinal muscular atrophy, and new anticancer drugs that act on genetic biomarkers rather than any specific type of cancer. Even though EAPs and novel therapeutic approaches have brought huge benefits for public health, their implementation is limited by several challenges, including the high risk of safety-related label changes for medicines authorized through the accelerated procedure, the high costs, and the reimbursement and access concerns. In this context, regulatory agencies should provide the best conditions for the implementation of the described new tools

    Supplementation with ribonucleotide-based ingredient (Ribodiet®) lessens oxidative stress, brain inflammation, and amyloid pathology in a murine model of Alzheimer

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    Abstract Alzheimer's disease (AD) is the most common type of dementia worldwide, characterized by the deposition of neurofibrillary tangles and amyloid-β (Aβ) peptides in the brain. Additionally, increasing evidence demonstrates that a neuroinflammatory state and oxidative stress, iron-dependent, play a crucial role in the onset and disease progression. Besides conventional therapies, the use of natural-based products represents a future medical option for AD treatment and/or prevention. We, therefore, evaluated the effects of a ribonucleotides-based ingredient (Ribodiet®) in a non-genetic mouse model of AD. To this aim, mice were injected intracerebroventricularly (i.c.v.) with Aβ1–42 peptide (3 µg/3 μl) and after with Ribodiet® (0.1–10 mg/mouse) orally (p.o.) 3 times weekly for 21 days following the induction of experimental AD. The mnemonic and cognitive decline was then evaluated, and, successively, we have assessed ex vivo the modulation of different cyto-chemokines on mice brain homogenates. Finally, the level of GFAP, S100β, and iron-related metabolic proteins were monitored as markers of reactive gliosis, neuro-inflammation, and oxidative stress. Results indicate that Ribodiet® lessens oxidative stress, brain inflammation, and amyloid pathology via modulation of iron-related metabolic proteins paving the way for its rationale use for the treatment of AD and other age-related diseases
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