1,721,102 research outputs found
Does poly(ADP-ribosyl)ation regulate the DNA methylation pattern?
No full textThe existence of a possible correlation between poly(ADP-ribosyl)ation and DNA methylation processes was investigated. In vivo and in vitro experiments were carried out on L929 mouse fibroblasts preincubated for 24 h with or without 3-aminobenzamide, a well-known inhibitor of poly(ADP-ribose) polymerase. Both experimental approaches evidenced a close relationship between these two important nuclear enzymatic mechanisms, suggesting that the poly(ADP-ribosyl)ated isoform of H1 histone and/or long and branched protein-free ADP-ribose polymers could act as protecting agents against full methylation of the CpG dinucleotides in genomic DNA
Mouse CpG island Htf9: dependence of its unmethylated state on the poly(ADP-ribosyl)ation process
No full textEnergy Saving in Link Stability Routing Protocol
Full text linkBecause the CPU is a very expensive resource in mobile ad hoc networks (MANETs), it is very important to consider the overhead introduced in a routing protocol. Many theories have been hypothesized with the aim of minimizing it. But how much is the energy consumption from a network node’s battery induced by the routing protocol overhead? In a previous work, we dealt with a routing protocol based on link stability (link duration observed in a time interval). In this work, we attempt to hypothesize a model for conserving the battery energy consumed by nodes in a MANET adopting the link stability routing protocol
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Indexes of tobacco smoke contribution to environmental particulates based on molecular fingerprints of alkanes
No full textTobacco smoke (TS) is the source of a number of toxicants affecting the atmosphere and poses a threat to smokers and the whole
community. Chemical, physical, and toxicological features of smoking products (vapors as well as mainstream, side stream, and
third-hand smoke) have been investigated extensively. Special attention is paid to organic compounds (individually or in
combination giving rise to peculiar molecular fingerprints), potentially able to act as “chemical signature” of TS. In this regard,
the percent distribution of long-chainnormal, iso, and anteiso alkanes was ascertained as typical of TS. Nevertheless, until now
no indexes have been identified as suitable for assessing the global TS contribution to environmental pollution, e.g., the TS
percentage in carbonaceous aerosol and in deposited dusts, the only exception consisting in the use of nicotelline as tracer. This
paper describes the results of an extensive study aimed at chemically characterizing the nonpolar lipid fraction associated to
suspended particulates (PMs) and deposition dusts (DDs) collected at indoor and outdoor locations. Based on the iso, anteiso, and
normal C29–C34 alkane profile in the samples as well in tobacco smoke- and no-TS-related emissions (literature data), various
parameters describing the distribution of compounds were investigated. Finally, a cumulative variable was identified as the
tobacco smoke impact index (TS%) suitable for estimating the TS percentage occurring in the particulate matter. The TS% rates
were plotted vs. the exceedance of normal C31 alkane with respect to the average of C29 and C33 homologs, which results higher
in TS than in most other emissions, revealing a link in the case of suspended particulates but not of deposited dusts. According to
back analysis carried out on all particulate matter sets, it was found that traces of TS affect even remote areas, while inside the
smokers’ homes the contributions of TS to PM could account for up to ~61% and ~10%, respectively, in PM and DD. This
confirms the need of valuing the health risk posed by TS to humans, by means of tools easy to apply in extensive investigations
Inquinamento di ambenti indoor da farmaci e sostanze per la cura personale
No full textE’ stato effettuato uno studio preliminare riguardo alla presenza di sostanze farmaceutiche e per la cura personale in due tipologie d’ambiente indoor: un ospedale e una farmacia. In specie, cinque ambienti sono stati individuati nell’ospedale (ingresso, sala ticket, bar, cappella e ufficio-studio) e due nella farmacia (sala di esposizione/vendita e locale scala interno). L’indagine è stata compiuta sulle polveri di deposizione, raccolte su superfici piane orizzontali poste a 1.8-2.0 m d’altezza. L’estensione superficiale (0.15÷0.50 m2) e la durata dell’esposizione (1÷60 d) variavano con le postazioni, in base alla frequenza delle operazioni di pulizia dei locali. I carichi di contaminante sono stati stimati sia in termini di velocità di deposizione giornaliera per unità di superficie [μg/(m2*d)], sia di concentrazione di massa (μg/g).
Le sostanze oggetto d’indagine erano:
- aspirina, paracetamolo, acetilcisteina, acido p-idrossibenzoico, ibuprofen, naproxen, fenoprefen, ketoprofen, diclofenac (sulfanilammide e fenofibrato sono risultati assenti per tutti gli ambienti);
- nonilfenolo, bisfenolo A, metilparaben, etilparaben, propilparaben; tonalide, galaxolide, N,N-dietil-meta-toluammide (DEET).
Inoltre, sono stati esaminati gli ftalati, in quanto generici indicatori d’inquinamento e, al tempo stesso, riconosciuti interferenti endocrini.
I risultati saranno presentati al Convegno; in ogni caso, si sono riscontrate ampie differenze tra la farmacia e l’ospedale e anche tra gli ambienti della medesima struttura, non solo per le concentrazioni nette ma anche per le composizioni percentuali
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Indexes of tobacco smoke contribution to environmental particulates based on molecular fingerprints of alkanes.
No full textTobacco smoke (TS) is the source of a number of toxicants affecting the atmosphere
and poses a threat to smokers and the whole community. Chemical, physical and
toxicological features of smoking products (vapours as well as mainstream, side
stream and third hand smoke) have been investigated extensively. Special attention is
paid to organic compounds (individually or in combination giving raise to peculiar
molecular fingerprints), potentially able to act as “chemical signature” of TS. At this
regard, the percent distribution of long-chain normal , iso and anteiso alkanes was
ascertained as typical of TS. Nevertheless, until now no indexes have been identified
as suitable for assessing the global TS contribution to environmental pollution, e.g. the
TS percentage in carbonaceous aerosol and in deposited dusts, the only exception
consisting in the use of nicotelline as tracer. This paper describes the results of an
extensive study aimed at chemically characterizing the non-polar lipid fraction
associated to suspended particulates (PMs) and deposition dusts (DDs) collected at
indoor and outdoor locations. Based on the iso , anteiso and normal C 29 -C 34
alkane profile in the samples as well in tobacco smoke and no-TS related emissions
(literature data), various parameters describing the distribution of compounds were
investigated. Finally, a cumulative variable was identified as tobacco smoke impact
index (TS%) suitable for estimating the TS percentage occurring in the particulate
matter. The TS% rates were plotted vs. the exceedance of normal C 31 alkane with
respect to average of C 29 and C 33 homologues, which results higher in TS than in
most other emissions, revealing a link in the case of suspended particulates but not of
deposited dusts. According to back analysis carried out on all particulate matter sets, it
was found that traces of TS affect even remote areas, while inside the smokers’ homes
the contributions of TS to PM could account for up to ~61% and ~10%, respectively, in
PM and DD. This confirms the need of valuing the health risk posed by TS to humans,
by means of tools ease to apply in extensive investigations
Potent inhibitory activity of taniborbactam towards NDM-1 and NDM-1Q119X mutants, and in vitro activity of cefepime/taniborbactam against MBLs producing Enterobacterales
No full textObjective: This study aimed to investigate the in vitro activity of taniborbactam (VNRX-5133), a novel broad-spectrum bicyclic boronate, against NDM-1 and Q119E, Q119K, Q119C, Q119F, Q119V, and Q119Y NDM-1 variants, which showed an increased activity towards some β-lactams, including cefepime. Methods: Inhibition kinetic assays were spectrophotometrically performed using cefepime (50 μM) as the reporter substrate and 80 nM of each enzyme. Taniborbactam behaves as a competitive inhibitor towards NDM-1 and NDM-1 Q119 variants with lower Ki values (range 3–16 nM). The phenotypic profile was assessed in both Enterobacterales clinical isolates and engineered Escherichia coli BL21(DE3) strains by conventional broth microdilution procedures according to the Clinical and Laboratory Standards Institute (CLSI). Results: Taniborbactam at a fixed concentration of 4 mg/L was able to restore activity of cefepime in 24 of 26 Enterobacterales clinical isolates harbouring metallo-β-lactamases with MIC50/MIC90 values of 14 mg/L. Cefepime MICs were drastically reduced in all clinical isolates and in NDM-1 and Q119X producing Escherichia coli BL21(DE3). Taniborbactam was unable to restore susceptibility to cefepime in two IMP variants producing clinical isolates. Conclusion: The inhibition level of NDM enzymes provided by taniborbactam protects the antibacterial activity of cefepime from this important metallo-β-lactamase
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