Internal stresses and breakup of rigid isostatic aggregates in homogeneous and isotropic turbulence

By characterising the hydrodynamic stresses generated by statistically homogeneous and isotropic turbulence in rigid aggregates, we estimate theoretically the rate of turbulent breakup of colloidal aggregates and the size distribution of the formed fragments. The adopted method combines Direct Numerical Simulation of the turbulent field with a Discrete Element Method based on Stokesian dynamics. In this way, not only the mechanics of the aggregate is modelled in detail, but the internal stresses are evaluated while the aggregate is moving in the turbulent flow. We examine doublets and cluster-cluster isostatic aggregates, where the failure of a single contact leads to the rupture of the aggregate and breakup occurs when the tensile force at a contact exceeds the cohesive strength of the bond. Due to the different role of the internal stresses, the functional relationship between breakup frequency and turbulence dissipation rate is very different in the two cases. In the limit of very small and very large values, the frequency of breakup scales exponentially with the turbulence dissipation rate for doublets, while it follows a power law for cluster-cluster aggregates. For the case of large isostatic aggregates it is confirmed that the proper scaling length for maximum stress and breakup is the radius of gyration. The cumulative fragment distribution function is nearly independent of the mean turbulence dissipation rate and can be approximated by the sum of a small erosive component and a term that is quadratic with respect to fragment size.Comment: 31 pages, 19 figure

Living "in the glow of the cyber-capital.": finance capital in Don DeLillo's fiction

The present thesis reads Don DeLillo’s fiction as expressive of the process of financialization which emerged in response to the 1970s capitalist crisis in the United States and gave rise to a specific social materiality and peculiar “structure of feeling” grounded in finance capital. I will argue that DeLillo’s works offer a powerful representation and critique of the workings of finance capital and of American hegemony pursued via the emergence, consolidation and expansion of finance. As DeLillo’s novels depict a specifically finance-driven US hegemony, they also register the attempts to resist such hegemony. Simultaneously, I shall focus on DeLillo’s analysis of a culture immersed in what Keynes called “the fetish of liquidity”, and on DeLillo’s investigation of how the seemingly dematerialising power of speculative capital modifies the construction of a new social materiality and human experience. By articulating a comparison between specific mechanisms within finance capital and the workings of mourning and melancholia, I shall explore the anxiety and dread pervading DeLillo’s characters as originating within the erasure of the commodity form from the dominant financial mode. Within such purview, I will first explore those texts, written in the 1970s, which best depict the crisis in US capitalism and the response to such crisis via the emergence of a chiefly financial economic and cultural mode. Subsequently, I will investigate DeLillo’s latest production in order to highlight how such works expose the contradictions and limitations of a finance-dominated economy and its attendant “structure of feeling”, and express an ever-growing need to return to less virtual, less evanescent forms of economic production

Quantitative risk assessment on a hydrogen refuelling station

The Directive 2014/94/UE (DAFI, Alternative Fuel Initiative Directive) on the deployment of alternative fuels (i.e. hydrogen) infrastructures has been recently transposed into national law in Italy. Consequently, the technical regulation on fire prevention for H2fuelling stations has been updated, in order to consider the current maximum delivery pressure (700 bar) of gaseous hydrogen for road vehicles. This technical regulation establishes the prescriptive safety distance from a piece of equipment. In the case of a new station, an assessment of the frequency of the event and its potential consequences is necessary. This is to understand which risk can reasonably be mitigated by a safety distance or whether additional mitigation or prevention measures should be taken. This paper presents the quantitative risk assessment (QRA) study on a hydrogen station planned to be installed, study which aims at determining the safety distances. Such study utilizes the Sandia-developed QRA tool, Hydrogen Risk Analysis Model (HyRAM), to calculate risk values when developing risk-equivalent plans. HyRAM combines reduced order deterministic models that characterize hydrogen release and flame behavior with probabilistic risk models to quantify risk values. Thanks to HyRAM tool it is possible to estimate physical effects and consequences on people and structures and plants, related to risk scenarios, by means of a damage model library. Use of risk assessment may allow station owners and designers to flexibly define station-specific mitigations, with the purpose of achieving equal or better levels of safety with respect to prescriptive recommendation levels, as suggested by ISO19880-1 (2018)

Severe bloodstream infection due to KPC-producer e coli in a renal transplant recipient treated with the double-carbapenem regimen and analysis of in vitro synergy testing a case report

Transplant recipients are at high risk of infections caused by multidrug resistant microorganisms. Due to the limited thera- peutic options, innovative antimicrobial combinations against carbape- nem-resistant Enterobacteriaceae causing severe infections are necessary. A 61-year-old woman with a history of congenital solitary kidney underwent renal transplantation. The postoperative course was compli- cated by nosocomial pneumonia due to Stenotrophomonas maltophilia and pan-sensitive Escherichia coli, successfully treated with antimicrobial therapy. On postoperative day 22, diagnosis of surgical site infection and nosocomial pneumonia with concomitant bacteremia due to a Kle- bisella pneumoniae carbapenemase-producer E coli was made. The patient was treated with the double-carbapenem regimen (high dose of merope- nem plus ertapenem) and a potent synergistic and bactericidal activity of this un-conventional therapeutic strategy was observed in vitro. Despite a microbiological response with prompt negativity of blood cultures, the patient faced a worse outcome because of severe hemorrhagic shock. The double-carbapenem regimen might be considered as a rescue therapy in those subjects, including transplant recipients, in whom previous antimicrobial combinations failed or when colistin use might be discouraged. Performing in vitro synergy testing should be strongly encouraged in cases of infections caused by pan-drug resistant strains, especially in high-risk patients

Cerrado e etnoveterinária: o que se sabe em Jataí - GO?

A construção do conhecimento humano sobre o uso de plantas medicinais partiu da observação da relação animal-planta e o resgate de informações valiosas nesta área do conhecimento, pouco pesquisado no Cerrado brasileiro, pode ser útil no estabelecimento de novas relações e/ou manutenção daquelas já existentes. O objetivo deste estudo foi investigar e documentar o conhecimento popular local sobre as plantas com uso na Medicina Veterinária. Os 28 informantes foram amostrados pelo método “snow ball” e submetidos a entrevistas semiestruturadas. Os dados coletados foram submetidos à análise estatística descritiva e de variância. O conhecimento etnoveterinário de homens e mulheres revelou-se significativamente maior entre mulheres (P<0,0001). As plantas citadas foram coletadas, identificadas botanicamente e agrupadas em 21 famílias e 25 gêneros. Fabaceae e Euphorbiaceae apresentaram maior frequência de espécies citadas (14% cada). O hábito de crescimento das espécies identificadas foi predominantemente arbóreo (44%). As indicações terapêuticas relatadas foram agrupadas em oito categorias de uso e a categoria DSTe (desordens do sistema tegumentar) apresentou o maior fator de consenso entre os informantes (ICF = 0,53). Estabelecidos os valores de uso reportado (RU), consenso de uso (UCs) e diversidade de uso (UDs) as espécies Chiococca brachiata Ruiz & Pav., Chenopodium ambrosioides L., Stryphnodendron adstringens (Mart.) Coville e Strychnos pseudoquina A. St.- Hil., revelaram-se as de maior importância etnoveterinária para a população pesquisada. Este estudo permitiu um levantamento preliminar sobre as plantas de uso terapêutico veterinário na região, resgatando o saber popular local e gerou informações que podem ser úteis para pesquisas futuras

Higher levels of osteoprotegerin and immune activation/immunosenescence markers are correlated with concomitant bone and endovascular damage in HIV-suppressed patients

HIV-infected patients appear to have a significantly greater risk of non-AIDS comorbidities such as osteoporosis and atherosclerosis. Subjects with osteoporosis are at a higher risk of developing cardiovascular disease than those with normal bone mass, therefore a possible relation between these two conditions can be hypothesized. In the setting of HIV infection, several factors might contribute to bone disease and endothelial dysfunction. The aim of our study was to evaluate the relationship between bone and cardiovascular disease and to investigate the role of traditional factors, T-cell phenotype and osteoprotegerin in HIV positive subjects on effective antiretroviral therapy. We included 94 HIV positive subjects on antiretroviral therapy with virological suppression and 41 healthy subjects matched for age and gender as a control group. Carotid-Intima Media Thickness (c-IMT) and bone mineral density (BMD) were performed by ultrasound and DEXA, respectively. CD4+/CD8+ T-cell activation, senescence and osteoprotegerin plasma levels were measured by flow-cytometry and ELISA, respectively. Among HIV positive patients, 56.4% had osteopenia/osteoporosis and 45.7% had pathological c-IMT (&gt;0.9mm). Subjects with pathological c-IMT and BMD exhibited higher CD4+ and CD8+ activated, CD8+ senescent and osteoprotegerin than subjects with normal c-IMT and BMD. HIV positive subjects with osteopenia/osteoporosis had higher c-IMT than subjects with normal BMD, and linear regression analysis showed a negative correlation between BMD and c-IMT. Several factors are implicated in the pathogenesis of non-AIDS comorbidities in HIV positive patients. Osteoprotegerin together with inflammation and immunosenescence in HIV positive patients could affect bone and vascular system and could be considered as a possible common link between these two diseases

Inhibition of HSP70 expression by calcium ionophore A23187 in human cells. An effect independent of the acquisition of DNA-binding activity by the heat shock transcription factor

Heat shock proteins (HSPs) are induced in mammalian cells in a variety of pathophysiological states and have an important role in cytoprotection in vitro and in vivo. In this study, we report that the calcium ionophore A23187, a glucose-regulated protein (GRP) inducer, dramatically inhibits HSP70 synthesis and HSP70 mRNA transcription after induction by heat shock, sodium arsenite, or prostaglandin A1 treatment in human K562 cells. A23187 does not suppress, and it actually prolongs, the DNA-binding activity of the human heat shock transcription factor (HSF), while it alters HSF1 phosphorylation in heat shock-treated cells. To inhibit HSP70 expression, A23187 needs to be present during heat shock, while treatment before or after heat shock does not affect HSP70 mRNA transcription. The GRP inducer thapsigargin, which specifically inhibits the endoplasmic reticulum Ca2+-ATPase, has no effect on heat-induced HSP70 synthesis, indicating that A23187 inhibitory activity is not due to depletion of intracellular calcium stores and is independent of the concomitant induction of GRP genes. Inhibition of HSP70 expression is correlated with alterations in HSF1 phosphorylation in heat-shocked cells, but not in sodium arsenite-treated cells, indicating that different mechanisms may be involved in mediating A23187 inhibitory activity

Usporedbeno istraživanje metoda prikupljanja podataka u procesu sestrinske njege: otkrivanje nuspojava kemoterapije pomoću upitnika za samoprocjenu

Toxicity of chemotherapy is a factor that most negatively affects the quality of life of cancer patients. Monitoring of side effects and adverse effects may be subject to errors due to various factors such as the lack of privacy during data collection, shame on the part of the patient to talk about some issues, lack of recognition of symptoms and/or unawareness of side effects of treatments, and/or inappropriate reference model of data collection. In order to assist caregivers in proper data collection, a ‘self-reporting questionnaire’ was designed. The questionnaire was developed using validated scales such as the Common Terminology Criteria for Adverse Event, Edmonton Symptom Assessment Scale and Douleur Neuropathique en 4 Questions. The survey involved the population of patients scheduled for chemotherapy in Day Hospital at the Campus Bio-Medico University Hospital, Rome, between June and July 2015. During the period of observation, 367 patients were admitted to Day Hospital, 57.5% of women and 38.4% of men, average age 64 years, for a total of 622 accesses; of these, only 173 were interviewed by the nursing staff in relation to side effects and toxicity. During the trial, 381 patients were involved, of which 60.1% of women (p=0.8) and 38.3% of men (p=0.9), average age 63 years (p=0.9), for a total of 611 accesses and 498 self-reporting questionnaires administered. At the end of the trial period, in order to evaluate usability, an evaluation questionnaire was given to medical personnel, including five doctors and six nurses, to consider possible amendments to the instrument and its perceived effectiveness. Comparative analysis of data collected during the observation period and the trial showed how the use of the self-reporting questionnaire allowed for detection of side effects of chemotherapy earlier and in a more detailed way than relying only on medical examination and unstructured interview by nursing staff. It also enabled reaching a larger number of users. In conclusion, the use of self-reporting systems, together with the work and clinical judgment of the expert, can contribute to improvement in the patient quality of life, corroborating nurse interviews through a precise and systematic data collection process that reduces the amount of interpretation of symptoms by the patient and the caregiver, while providing them with precise instructions on what to report and how to report it. The significant and rapid spread of computers, tablets and smartphones allows for speculating on further use and implementation of this system through its computerized application.Toksičnost kemoterapije je čimbenik koji ima najteži učinak na kvalitetu života u bolesnka s karcinomom. Praćenje nuspojava i štetnih učinaka može biti podložno greškama zbog raznih čimbenika kao što je nedostatna zaštita povjerljivosti ­tijekom prikupljanja podataka, nevoljkosti bolesnika da govori o nekim problemima, neprepoznavanje simptoma i/ili ­nepoznavanje nuspojava liječenja i/ili neodgovarajući referentni model prikupljanja podataka. Zato smo izradili upitnik za samoprocjenu kako bismo pomogli u ispravnom prikupljanju podataka onima koji pružaju skrb ovim bolesnicima. Upitnik je izrađen uz pomoć provjerenih ljestvica kao što su Common Terminology Criteria for Adverse Event, Edmonton Symptom ­Assessment Scale i Douleur Neuropathique en 4 Questions. Istraživanje je obuhvatilo bolesnike naručene za kemoterapiju u Dnevnoj bolnici Sveučilišne bolnice Campus Bio-Medico u Rimu u lipnju i srpnju 2015. godine. U tom razdoblju u Dnevnu bolnicu je primljeno 367 bolesnika, 57,5% žena i 38,4% muškaraca prosječne dobi od 64 godine, za ukupno 622 pristupa. Od svih tih bolesnika sestrinsko osoblje je samo njih 173 ispitalo o nuspojavama i toksičnosti. Za vrijeme istraživanja bio je uključen 381 bolesnik, od toga 60,1% žena (p=0,8) i 38,3% muškaraca (p=0,9) prosječne dobi od 63 godine (p=0,9), za ­ukupno 611 pristupa i 498 izdanih upitnika za samoprocjenu. Kako bismo procijenili primjenjivost ovoga upitnika, na kraju istraživanja upitnik za njegovu procjenu je podijeljen medicinskom osoblju uključujući pet liječnika i šest medicinskih sestara kako bi razmotrili moguće potrebne dopune ovoga instrumenta te njegovu učinkovitost. Usporedbena analiza podataka prikupljenih tijekom istraživanja pokazala je da je primjena upitnika za samoprocjenu omogućila otkrivanje nuspojava kemoterapije ranije i podrobnije nego kad se to oslanjalo samo na medicinski pregled i nestrukturirani razgovor sestrinskog osoblja s bolesnicima. Uz to, ovom metodom je obuhvaćen veći broj korisnika. U zaključku, primjena sustava za samoprocjenu zajedno sa stručnim radom i kliničkom prosudbom može doprinijeti poboljšanju bolesnikove kvalitete života, pružiti potporu razgovoru sestrinskog osoblja s bolesnikom kroz proces preciznog i sustavnog prikupljanja podataka, čime se znatno smanjuje tumačenje simptoma od strane bolesnika i osoba koje ih njeguju, ali im pruža točne upute o čemu trebaju izvijestiti i kako. Zahvaljujući značajnom i brzom širenju računala, tableta i ‘pametnih telefona’ može se promišljati o daljnjoj primjeni ovoga sustava kroz njegovu računalnu aplikaciju

One special question to start with: can HIF/NFkB be a target in inflammation?

Hypoxia and Inflammation are strictly interconnected with important consequences at clinical and therapeutic level. While cell and tissue damage due to acute hypoxia mostly leads to cell necrosis, in chronic hypoxia, cells that are located closer to vessels are able to survive adapting their phenotype through the expression of a number of genes, including proinflammatory receptors for alarmins. These receptors are activated by alarmins released by necrotic cells and generate signals for master transcription factors such as NFkB, AP1, etc. which control hundreds of genes for innate immunity and damage repair. Clinical consequences of chronic inflammatory reparative response activation include cell and tissue remodeling, damage in the primary site and, the systemic involvement of distant organs and tissues. Thus every time a tissue environment becomes stably hypoxic, inflammation can be activated followed by chronic damage and cell death or repair with vessel proliferation and fibrosis. This pathway can occur in cancer, myocardial infarction and stroke, diabetes, obesity, neurodegenerative diseases, chronic and autoimmune diseases and age-related diseases. Interestingly, proinflammatory gene expression can be observed earlier in hypoxic tissue cells and, in addition, in activated resident or recruited leukocytes. Herewith, the reciprocal relationships between hypoxia and inflammation will be shortly reviewed to underline the possible therapeutic targets to control hypoxia-related inflammation in a number of epidemiologically important human diseases and conditions