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1.
Ann Ig ; 35(3): 282-296, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35861690

RESUMO

Background: The prevalence and mortality of sepsis in Internal Medicine Units (IMUs) is poorly understood as most of the data derive from studies conducted in Intensive Care Units. Aim of SEpsis Management in INternal medicine Apulia (SEMINA) study was to determine the prevalence of sepsis and the characteristics and outcomes of patients with Sepsis-3 criteria admitted in Apulia's Internal Medicine Units for over six months. Methods: The SEpsis Management in INternal medicine of Apulia study was a prospective, multicentre, observational study. Adult admissions to the 13 Apulia Region's Internal Medicine Units between November 15, 2018 and May 15, 2019 were screened for sepsis according to the Sepsis-3 criteria. Medical data were collected in electronic case report form. Results: Out of 7,885 adult patients of the Internal Medicine Units, 359 (4.55%) fulfilled the inclusion criteria, and 65 of them (18.1%) met the septic shock criteria. The patients enrolled were elderly, suffering from chronic poly-pathologies and from cognitive and functional impairment. The respiratory system was the most common site of infection and the most common pathogens isolated from blood cultures were Staphylococcus spp., E. coli, Klebsiella spp., Enterococcus spp. and Acinetobacter spp. The in-hospital fatality rate was 31.2% and was significantly higher for septic shock. Sequential Organ Failure Assessment score, dementia and infections from Acinetobacter spp. were independent risk factors for mortality. Conclusions: A high prevalence of sepsis and a high fatality rate were detected in Apulia Region's Internal Medicine Units. The high fatality rate observed in our study could be related to the underlying diseases and to the vulnerability of elderly patients admitted to our Internal Medicine Units.


Assuntos
Sepse , Choque Séptico , Adulto , Idoso , Humanos , Mortalidade Hospitalar , Unidades de Terapia Intensiva/estatística & dados numéricos , Estudos Prospectivos , Sepse/epidemiologia , Sepse/microbiologia , Sepse/terapia , Choque Séptico/epidemiologia , Choque Séptico/microbiologia , Choque Séptico/terapia , Prevalência
2.
Front Chem ; 9: 751054, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34778206

RESUMO

Using the simple (symmetric) Hubbard dimer, we analyze some important features of the GW approximation. We show that the problem of the existence of multiple quasiparticle solutions in the (perturbative) one-shot GW method and its partially self-consistent version is solved by full self-consistency. We also analyze the neutral excitation spectrum using the Bethe-Salpeter equation (BSE) formalism within the standard GW approximation and find, in particular, that 1) some neutral excitation energies become complex when the electron-electron interaction U increases, which can be traced back to the approximate nature of the GW quasiparticle energies; 2) the BSE formalism yields accurate correlation energies over a wide range of U when the trace (or plasmon) formula is employed; 3) the trace formula is sensitive to the occurrence of complex excitation energies (especially singlet), while the expression obtained from the adiabatic-connection fluctuation-dissipation theorem (ACFDT) is more stable (yet less accurate); 4) the trace formula has the correct behavior for weak (i.e., small U) interaction, unlike the ACFDT expression.

3.
Front Chem ; 9: 746735, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34692643

RESUMO

The Extended Koopman's Theorem (EKT) provides a straightforward way to compute charged excitations from any level of theory. In this work we make the link with the many-body effective energy theory (MEET) that we derived to calculate the spectral function, which is directly related to photoemission spectra. In particular, we show that at its lowest level of approximation the MEET removal and addition energies correspond to the so-called diagonal approximation of the EKT. Thanks to this link, the EKT and the MEET can benefit from mutual insight. In particular, one can readily extend the EKT to calculate the full spectral function, and choose a more optimal basis set for the MEET by solving the EKT secular equation. We illustrate these findings with the examples of the Hubbard dimer and bulk silicon.

4.
Faraday Discuss ; 224(0): 467-482, 2020 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-32940315

RESUMO

The optical spectra of two-dimensional (2D) periodic systems provide a challenge for time-dependent density-functional theory (TDDFT) because of the large excitonic effects in these materials. In this work we explore how accurately these spectra can be described within a pure Kohn-Sham time-dependent density-functional framework, i.e., a framework in which no theory beyond Kohn-Sham density-functional theory, such as GW, is required to correct the Kohn-Sham gap. To achieve this goal we adapted a recent approach we developed for the optical spectra of 3D systems [S. Cavo, J. A. Berger and P. Romaniello, Phys. Rev. B, 2020, 101, 115109] to those of 2D systems. Our approach relies on the link between the exchange-correlation kernel of TDDFT and the derivative discontinuity of ground-state density-functional theory, which guarantees a correct quasi-particle gap, and on a generalization of the polarization functional [J. A. Berger, Phys. Rev. Lett., 2015, 115, 137402], which describes the excitonic effects. We applied our approach to two prototypical 2D monolayers, h-BN and MoS2. We find that our protocol gives a qualitatively good description of the optical spectrum of h-BN, whereas improvements are needed for MoS2 to describe the intensity of the excitonic peaks.

5.
J Chem Theory Comput ; 15(9): 5080-5086, 2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31390204

RESUMO

In this work, we explore the performance of a recently derived many-body effective energy theory for the calculation of photoemission spectra in the regime of strong electron correlation. We apply the theory to paramagnetic MnO, FeO, CoO, and NiO, which are typical examples of strongly correlated materials and, therefore, a challenge for standard theories. We show that our method opens a correlation gap in all of the oxides studied without breaking the symmetry. Although the materials seem similar, we show that an analysis of the occupation numbers reveals that the nature of the gap is not the same for these materials. Overall, the results are very promising, although improvements are clearly required, since the band gap is overestimated for all of the systems studied. We indicate some possible strategies to further develop the theory.

6.
J Chem Phys ; 143(2): 024108, 2015 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-26178091

RESUMO

In this work, we explore the performance of approximations to electron correlation in reduced density-matrix functional theory (RDMFT) and of approximations to the observables calculated within this theory. Our analysis focuses on the calculation of total energies, occupation numbers, removal/addition energies, and spectral functions. We use the exactly solvable Hubbard dimer at 1/4 and 1/2 fillings as test systems. This allows us to analyze the underlying physics and to elucidate the origin of the observed trends. For comparison, we also report the results of the GW approximation, where the self-energy functional is approximated, but no further hypothesis is made concerning the approximations of the observables. In particular, we focus on the atomic limit, where the two sites of the dimer are pulled apart and electrons localize on either site with equal probability, unless a small perturbation is present: this is the regime of strong electron correlation. In this limit, using the Hubbard dimer at 1/2 filling with or without a spin-symmetry-broken ground state allows us to explore how degeneracies and spin-symmetry breaking are treated in RDMFT. We find that, within the used approximations, neither in RDMFT nor in GW, the signature of strong correlation is present, when looking at the removal/addition energies and spectral function from the spin-singlet ground state, whereas both give the exact result for the spin-symmetry broken case. Moreover, we show how the spectroscopic properties change from one spin structure to the other.

7.
Phys Rev E Stat Nonlin Soft Matter Phys ; 84(2 Pt 1): 021112, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21928954

RESUMO

Our theoretical and numerical investigation of the movement of an object that partitions a microtubule filled with small particles indicates that vibrations warranted by thermal equilibrium are reached only after a time that increases exponentially with the number of particles involved. This points to a basic mechanical process capable of breaching, on accessible time scales, the ultimate ergodic constraints that force randomness on bound microscale and nanoscale systems.

8.
J Pers Assess ; 77(3): 464-74, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11781033

RESUMO

The Comprehensive System (CS; Exner, 1974, 1978) for scoring Rorschach responses is the most widely taught and most widely accepted system in use today. The complexity and labor- intensive nature of the CS makes the issue of scoring accuracy a central concern. Twenty-one graduate psychology students and 12 professionals scored 20 Rorschach responses drawn from normal and clinical protocols. In general. accuracy scores for both students and professionals were below acceptable levels. Accuracy scores were clearly better for the code categories of Location, DQ, Pairs, Popular, and Z than for Determinants, FQ, Content, and Special Scores. Responses from clinical protocols were subject to more error. The results suggest that high levels of scoring errors may exist in the field use of the CS. Training standards may need to be devised to insure scoring competence.


Assuntos
Projetos de Pesquisa/estatística & dados numéricos , Teste de Rorschach/estatística & dados numéricos , Estudantes/psicologia , Competência Clínica/estatística & dados numéricos , Educação de Pós-Graduação , Educação Profissionalizante , Humanos
10.
Am J Psychiatry ; 153(3): 376-81, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8610825

RESUMO

OBJECTIVE: This study investigated the correlates of a childhood history of anxiety disorders in adult patients participating in a longitudinal study of panic disorder. The authors hypothesized that a history of anxiety during childhood would be associated with higher rates of comorbid anxiety and depressive disorders, greater likelihood of anxiety disorders in family members, and greater chronicity, as reflected by decreased time spent in remission. METHOD: The presence of a childhood history of anxiety disorders was assessed by structured interview, and its association with comorbid anxiety and depressive disorders, family history, and select anxiety severity variables was examined in a replication sample of 94 patients. The influence of childhood anxiety on the prospectively ascertained course of disorder was assessed in a full group of 194 patients. RESULTS: Over half (54%) of the patients experienced anxiety disorders during childhood. These patients experienced higher rates of comorbid anxiety and depression, family history of anxiety, and increased levels of agoraphobia, panic frequency, and global severity of illness at baseline evaluation. Childhood anxiety disorders were not independently associated with the number of months in remission or the severity of illness over time, although a modest effect for this variable was evident when degree of avoidance and anxiety sensitivity at baseline were statistically controlled. CONCLUSIONS: Adult panic patients with a history of anxiety disorders in childhood have elevated rates of comorbid anxiety and depressive disorders and a tendency toward increased avoidance, but there was not strong evidence that these patients respond differently to treatment over time.


Assuntos
Transtornos de Ansiedade/epidemiologia , Transtorno de Pânico/epidemiologia , Adulto , Fatores Etários , Idade de Início , Transtornos de Ansiedade/diagnóstico , Criança , Comorbidade , Humanos , Estudos Longitudinais , Transtorno de Pânico/diagnóstico , Prevalência , Escalas de Graduação Psiquiátrica , Índice de Gravidade de Doença
11.
Am J Psychiatry ; 153(1): 110-3, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8540567

RESUMO

OBJECTIVE: The authors examined the prevalence and correlates of panic disorder in a group of patients who were referred for pulmonary function testing. METHOD: Patients (N = 115) were screened for the presence of panic attacks and panic disorder with a self-report questionnaire; a subgroup (N = 25) received structured diagnostic assessment. RESULTS: Of the 115 patients, 41% (N = 47) reported panic attacks and 17% (N = 20) met screening criteria for panic disorder. From the confirmed rate of panic disorder among the subgroup who received structured diagnostic assessment, the overall prevalence rate of panic disorder was estimated to be 11% and included six of the nine patients (67%) who had a diagnosis of chronic obstructive pulmonary disease. There were no significant differences between patients with and without panic in the severity of pulmonary function abnormalities or in the response to bronchodilators. However, patients with panic attacks were significantly more likely to report dyspnea at rest and irritable bowel symptoms and tended to report difficulty swallowing. CONCLUSIONS: This study suggests that panic disorder and subsyndromal panic are relatively common and may be unrecognized and inadequately treated in patients who present with respiratory symptoms.


Assuntos
Pneumopatias/epidemiologia , Transtorno de Pânico/epidemiologia , Obstrução das Vias Respiratórias/diagnóstico , Obstrução das Vias Respiratórias/epidemiologia , Comorbidade , Diagnóstico Diferencial , Feminino , Hospitais Gerais , Humanos , Pneumopatias/diagnóstico , Pneumopatias Obstrutivas/diagnóstico , Pneumopatias Obstrutivas/epidemiologia , Masculino , Pessoa de Meia-Idade , Transtorno de Pânico/diagnóstico , Prevalência , Escalas de Graduação Psiquiátrica , Encaminhamento e Consulta , Testes de Função Respiratória
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