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1.
J Chem Phys ; 157(24): 244504, 2022 Dec 28.
Article in English | MEDLINE | ID: mdl-36586975

ABSTRACT

We investigate the structural relaxation of a soft-sphere liquid quenched isochorically (ϕ = 0.7) and instantaneously to different temperatures Tf above and below the glass transition. For this, we combine extensive Brownian dynamics simulations and theoretical calculations based on the non-equilibrium self-consistent generalized Langevin equation (NE-SCGLE) theory. The response of the liquid to a quench generally consists of a sub-linear increase of the α-relaxation time with system's age. Approaching the ideal glass-transition temperature from above (Tf > Ta), sub-aging appears as a transient process describing a broad equilibration crossover for quenches to nearly arrested states. This allows us to empirically determine an equilibration timescale teq(Tf) that becomes increasingly longer as Tf approaches Ta. For quenches inside the glass (Tf ≤ Ta), the growth rate of the structural relaxation time becomes progressively larger as Tf decreases and, unlike the equilibration scenario, τα remains evolving within the whole observation time-window. These features are consistently found in theory and simulations with remarkable semi-quantitative agreement and coincide with those revealed in a previous and complementary study [P. Mendoza-Méndez et al., Phys. Rev. 96, 022608 (2017)] that considered a sequence of quenches with fixed final temperature Tf = 0 but increasing ϕ toward the hard-sphere dynamical arrest volume fraction ϕHS a=0.582. The NE-SCGLE analysis, however, unveils various fundamental aspects of the glass transition, involving the abrupt passage from the ordinary equilibration scenario to the persistent aging effects that are characteristic of glass-forming liquids. The theory also explains that, within the time window of any experimental observation, this can only be observed as a continuous crossover.


Subject(s)
Glass , Molecular Dynamics Simulation , Temperature , Transition Temperature , Glass/chemistry
2.
Rev. chil. enferm. respir ; 38(1): 11-19, mar. 2022. ilus, tab
Article in Spanish | LILACS | ID: biblio-1388167

ABSTRACT

Resumen El uso de escalas de predicción clínica puede incrementar la detección temprana de enfermedad pulmonar obstructiva crónica (EPOC). Su rendimiento en población latinoamericana ha sido pobremente estudiado. Nuestro objetivo fue determinar la validez y reproducibilidad del cuestionario PUMA, como herramienta de tamización en atención primaria en población colombiana, mediante un estudio tipo corte transversal; donde se establecieron las características operativas del cuestionario, área bajo la curva de características operativas del receptor (ACOR) y el mejor punto de corte para esta población. 1.980 sujetos fueron incluidos en el análisis. La prevalencia de EPOC correspondió a 18,9%. La capacidad discriminatoria del cuestionario fue de 0,69 (IC95%: 0,66-0,72), para un punto de corte óptimo mayor de 5, con una sensibilidad del 60%, especificidad 66% y un valor predictivo negativo de 88%. La escala PUMA para tamizaje de pacientes en riesgo de EPOC tiene una capacidad discriminatoria moderada y una excelente reproducibilidad en la población estudiada.


The use of clinical prediction scales may increase the early detection of chronic obstructive pulmonary disease (COPD). The performance characteristics of these scales in the Latin American population is poorly studied. We aimed to evaluate validity and reproducibility of PUMA questionnaire as a screening tool in primary care in a Colombian population. A cross-sectional study was performed. Operational characteristics of the questionnaire, the area under the received operator curve (AUROC), and the best cut-off point of the score were calculated. 1,980 individuals were included in this analysis. Prevalence of COPD was 18.9%. AUROC of the questionary was 0.69 (CI95%: 0.66-0.72), with an optimal cut-off point greater than 5 (sensitivity 60%, specificity 66%); predictive negative value was 88%. PUMA's scale for the screening of patients at risk of COPD has a moderate accuracy and an excellent reproducibility in the studied population.


Subject(s)
Humans , Male , Female , Adult , Middle Aged , Aged , Primary Health Care , Surveys and Questionnaires , Pulmonary Disease, Chronic Obstructive/diagnosis , Pulmonary Disease, Chronic Obstructive/epidemiology , Mass Screening , Prevalence , Cross-Sectional Studies , Predictive Value of Tests , Reproducibility of Results , Sensitivity and Specificity , Colombia/epidemiology
3.
Rev. guatemalteca cir ; 21(1): 22-28, 2015. tab
Article in Spanish | LILACS | ID: biblio-869917

ABSTRACT

Introducción: La residencia médica es un período de riesgo para el desarrollo de problemas de salud mental. Los estudios de ansiedad en residentesson contrastantes; sin embargo, se cree que los niveles de ansiedad son altos ya que los programas se desarrollan en hospitales nacionales que carecende recursos fsicos, materiales y humanos. El objetvo del presente estudio es determinar los niveles de ansiedad en médicos residentes en diferentesespecialidades empleando el cuestonario inventario de la ansiedad rasgo-estado (IDARE).Métodos: Se administró una encuesta electrónica para determinar el nivel de ansiedad en médicos residentes en diferentes especialidades del HospitalGeneral San Juan de Dios.Resultados: Se obtuvieron 132 encuestas para el análisis. La mayoría de los médicos encuestados son hombres (59%), solteros (83%) que no tenendependientes (79%), cursan residencia de cirugía o medicina interna (54%), trabajan más de 80 horas por semana (85%) y viajan menos de una horapara llegar al lugar de residencia (67%). El promedio del nivel de ansiedad-estado de los médicos residentes fue 46.94 puntos, mientras que el nivelpromedio de ansiedad-rasgo fue de 42.77 puntos. El 35% de los residentes poseen niveles de ansiedad medio y 59% altos en el momento de responderla encuesta; y el 56% posee niveles de ansiedad medio y 37% alto generalmente. No se encontró diferencia estadístcamente signifcatva en los nivelesde ansiedad en base a género, estado civil, tpo de residencia, dependientes y horas de tráfco. La única variable asociada con ansiedad fue la cantdadde horas de trabajo por semana.Conclusiones: La mayoría de los residentes encuestados poseen niveles de ansiedad medio-altos, la única variable asociada con niveles de ansiedadfue la cantdad de horas de trabajo por semana.


Background: Medical residency is a risky period for the development of mental health problems. Although anxiety studies in medical residents areinconclusive; we hypothesize anxiety levels in residents are high, since residency programs are developed in community hospitals that lack material andhuman resources. The aim of this study is to determine the levels of anxiety in medical residents of diferent specialtes using the State Trait-AnxietyInventary (STAI).Methods: An electronic poll with STAI was administered to medical residents of diferent specialtes of a tertary referral hospital.Results: We received 132 questonnaires for analysis. Most of the respondents are men (59%), single (83%), without dependents (79%), belong tosurgical or internal medicine residency (54%), work more than 80 hours per week (85%) and travel less than an hour to get to the hospital (67%). Theaverage level of state anxiety of the residents was 46.94 points, while the average level of trait anxiety was 42.77 points. Thirty fve percent of theresidents have medium anxiety levels and 59% high anxiety levels at the tme they answered the inventory; and 56% have medium anxiety levels and37% have high anxiety levels as a trait. We did not found a statstcal diference in anxiety levels based on gender, marital status, and type of residency,number of dependents or number of hours spent in trafc. The only variable that was associated with anxiety was the amount of work hours per week.Conclusions: Most of the residents have medium-high levels of anxiety; the only variable associated with anxiety levels was the amount of work hoursper week


Subject(s)
Humans , Burnout, Professional/diagnosis , Anxiety/diagnosis , Internship and Residency
4.
Phys Rev E Stat Nonlin Soft Matter Phys ; 90(5-1): 052301, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25493790

ABSTRACT

A self-consistent generalized Langevin-equation theory is proposed to describe the self- and collective dynamics of a liquid of linear Brownian particles. The equations of motion for the spherical harmonics projections of the collective and self-intermediate-scattering functions, F_{lm,lm}(k,t) and F_{lm,lm}^{S}(k,t), are derived as a contraction of the description involving the stochastic equations of the corresponding tensorial one-particle density n_{lm}(k,t) and the translational (α=T) and rotational (α=R) current densities j_{lm}^{α}(k,t). Similar to the spherical case, these dynamic equations require as an external input the equilibrium structural properties of the system contained in the projections of the static structure factor, denoted by S_{lm,lm}(k). Complementing these exact equations with simple (Vineyard-like) approximate relations for the collective and the self-memory functions we propose a closed self-consistent set of equations for the dynamic properties involved. In the long-time asymptotic limit, these equations become the so-called bifurcation equations, whose solutions (the nonergodicity parameters) can be written, extending the spherical case, in terms of one translational and one orientational scalar dynamic order parameter, γ_{T} and γ_{R}, which characterize the possible dynamical arrest transitions of the system. As a concrete illustrative application of this theory we determine the dynamic arrest diagram of the dipolar hard-sphere fluid. In qualitative agreement with mode coupling theory, the present self-consistent equations also predict three different regions in the state space spanned by the macroscopic control parameters η (volume fraction) and T* (scaled temperature): a region of fully ergodic states, a region of mixed states, in which the translational degrees of freedom become arrested while the orientational degrees of freedom remain ergodic, and a region of fully nonergodic states.

5.
Lupus ; 14(11): 890-5, 2005.
Article in English | MEDLINE | ID: mdl-16335581

ABSTRACT

The objective of this study was to identify the factors associated with important clinical outcomes in a case-control study of 213 patients with lupus nephritis. Included were 47% Hispanics, 44% African Americans and 9% Caucasians with a mean age of 28 years. Fifty-four (25%) patients reached the primary composite outcome of doubling serum creatinine, end-stage renal disease or death during a mean follow-up of 37 months. Thirty-four percent African Americans, 20% Hispanics and 10% Caucasians reached the primary composite outcome (P < 0.05). Patients reaching the composite outcome had predominantly proliferative lupus nephritis (WHO classes: 30% III, 32% IV, 18% V and 5% II, P < 0.025) with higher activity index score (7 +/- 6 versus 5 +/- 5, P < 0.05), chronicity index (CI) score (4 +/- 3 versus 2 +/- 2 unit, P < 0.025), higher baseline mean arterial pressure (MAP) (111 +/- 21 versus 102 +/- 14 mmHg, P < 0.025) and serum creatinine (1.9 +/- 1.3 versus 1.3 +/- 1.0 mg/dL, P < 0.025), but lower baseline hematocrit (29 +/- 6 versus 31 + 5%, P < 0.025) and complement C3 (54 +/- 26 versus 65 + 33 mg/dL, P < 0.025) compared to controls. More patients reaching the composite outcome had nephrotic range proteinuria compared to controls (74% versus 56%, P < 0.025). By multivariate analysis, CI (hazard ratio [95% CI] 1.18 [1.07-1.30] per point), MAP (HR 1.02 [1.00-1.03] per mmHg), and baseline serum creatinine (HR 1.26 [1.04-1.54] per mg/dL) were independently associated with the composite outcome. We concluded that hypertension and elevated serum creatinine at the time of the kidney biopsy as well as a high CI are associated with an increased the risk for chronic renal failure or death in patients with lupus nephritis.


Subject(s)
Kidney Failure, Chronic/mortality , Lupus Nephritis/mortality , Adult , Black or African American/statistics & numerical data , Case-Control Studies , Creatinine/blood , Female , Hispanic or Latino/statistics & numerical data , Humans , Kidney Failure, Chronic/ethnology , Lupus Nephritis/ethnology , Male , Predictive Value of Tests , Proportional Hazards Models , Risk Factors , White People/statistics & numerical data
6.
J Am Mosq Control Assoc ; 21(3): 310-5, 2005 Sep.
Article in English | MEDLINE | ID: mdl-16252523

ABSTRACT

The objective of this study was to determine some of the most important bionomic parameters related to the capacity of transmission of Trypanosoma cruzi and to estimate the potential transmission capacity and role of 3 groups of recent colonized Mexican Triatoma barberi, T. rubida sonoriana, and Meccus (formerly Triatoma) mazzottii in the prevalence of Chagas disease cases based on the distribution area of each species. Among the studied Triatominae species, the life cycle was shorter in T. r. sonoriana and longer in T. barberi, by as much as 4 times. The 1st and 5th instars had the highest rates of mortality in most of the studied species. Statistically significant shorter duration of feeding of instars was observed for T. r. sonoriana and longer duration was found for M. mazzottii when the species were compared. The mean number of blood meals per nymphal stadium was statistically greater in T. barberi than in T. r. sonoriana and M. mazzottii. Triatoma r. sonoriana and M. mazzotti had shorter defecation delay than in T. barberi and the delay was uniform in all instars. Most of the studied parameters showed that T. r. sonoriana and M. mazzotti could have an important potential role in the prevalence of Chagas disease cases where these species are commonly found.


Subject(s)
Reduviidae/growth & development , Triatoma/growth & development , Animals , Feeding Behavior , Female , Fertility , Life Cycle Stages , Reduviidae/parasitology , Triatoma/parasitology
7.
Phys Rev E Stat Nonlin Soft Matter Phys ; 68(3 Pt 1): 031202, 2003 Sep.
Article in English | MEDLINE | ID: mdl-14524753

ABSTRACT

Long-time self-diffusion coefficients of ferrofluid suspensions are derived from an effective Langevin equation approach. The dependences of these transport properties on the volume fraction of particles and the strength of interparticle interaction are investigated. Strong reduction of the rotational and the translational Brownian motion of the particles is manifested upon increase of particle-particle interaction or ferrofluid concentration.

8.
Gynecol Oncol ; 61(1): 11-5, 1996 Apr.
Article in English | MEDLINE | ID: mdl-8626096

ABSTRACT

Six hundred thirty-nine patients with CIN on referral Pap were evaluated cytocolposcopically at the first visit and decided whether to be treated the same day or not. One hundred ninety-two patients (30%) were considered negative. Follow-up evidenced later appearance of CIN in five of them. One hundred fifty-three (24%) were candidates for delayed treatment due to conditions contraindicating same-day treatment. Two hundred ninety-four patients (46%) were randomly allocated in LEEP (149) or excisional laser (145) arms, and treated the same day under local anesthesia. Both arms were comparable. There were three microinvasive carcinomas diagnosed in the surgical specimen. LEEP was faster and produced less bleeding than laser, although required a mean of four slices to remove the lesion. Arterial hypertension after anesthetic infiltration was detected in 26% of cases. Two intraoperative and two delayed bleeders required surgery. The size of lesion and surgical defect were larger than those reported in the literature. Margins were involved in 8 patients (2.7%). Only 4.7% (7/149) of patients randomized to LEEP and 3.4% (5/145) with excisional laser had persistent or recurrent CIN on follow-up. Factors predisposing to failure included depth of surgical defect, grade of lesion, and operator's expertise. With this approach, 69% of patients referred for cytology of CIN were adequately managed in the first visit, which contrasts to classical management that reaches the state of treatment in 30% of patients. LEEP appears to be faster, less costly, and requires less expertise. Its use in conjunction with adequate screening is recommended for developing countries.


Subject(s)
Conization , Developing Countries , Electrosurgery , Laser Therapy , Uterine Cervical Dysplasia/therapy , Uterine Cervical Neoplasms/therapy , Female , Humans , Neoplasm, Residual/pathology , Patient Dropouts , Postoperative Complications , Prospective Studies , Treatment Outcome
9.
Gynecol Oncol ; 61(1): 11-5, 1996 Apr.
Article in English | MEDLINE | ID: mdl-8812512

ABSTRACT

Six hundred thirty-nine patients with CIN on referral Pap were evaluated cytocolposcopically at the first visit and decided whether to be treated the same day or not. One hundred ninety-two patients (30%) were considered negative. Follow-up evidenced later appearance of CIN in five of them. One hundred fifty-three (24%) were candidates for delayed treatment due to conditions contraindicating same-day treatment. Two hundred ninety-four patients (46%) were randomly allocated in LEEP (149) or excisional laser (145) arms, and treated the same day under local anesthesia. Both arms were comparable. There were three microinvasive carcinomas diagnosed in the surgical specimen. LEEP was faster and produced less bleeding than laser, although required a mean of four slices to remove the lesion. Arterial hypertension after anesthetic infiltration was detected in 26% of cases. Two intraoperative and two delayed bleeders required surgery. The size of lesion and surgical defect were larger than those reported in the literature. Margins were involved in 8 patients (2.7%). Only 4.7% (7/149) of patients randomized to LEEP and 3.4% (5/145) with excisional laser had persistent or recurrent CIN on follow-up. Factors predisposing to failure included depth of surgical defect, grade of lesion, and operator's expertise. With this approach, 69% of patients referred for cytology of CIN were adequately managed in the first visit, which contrasts to classical management that reaches the state of treatment in 30% of patients. LEEP appears to be faster, less costly, and requires less expertise. Its use in conjunction with adequate screening is recommended for developing countries.

10.
Ginecol Obstet Mex ; 64: 18-20, 1996 Jan.
Article in Spanish | MEDLINE | ID: mdl-8948919

ABSTRACT

326 patients with the diagnosis of Preeclampsia-Eclampsia, were analyzed. There were 326 new born; 172 of them were female, and 154 male with a ratio 1.2/l. There is the probability of 1.6 times more for Eclampsia if the fetus is male. This report is in disagreement with other reports in world literature.


Subject(s)
Eclampsia/physiopathology , Adolescent , Adult , Female , Fetus , Humans , Infant, Newborn , Male , Pregnancy , Severity of Illness Index , Sex Characteristics
11.
Acta Med Port ; 7(1): 13-20, 1994 Jan.
Article in Portuguese | MEDLINE | ID: mdl-8184716

ABSTRACT

The authors present an audit to a multidisciplinary Intensive Care Unit of a tertiary Hospital (HSAC) over its first year (1/07/1991-30/06/1992). The total study population numbered 282 patients, 52.5% admitted from the emergency room. The mean age was 57.91 +/- 18.16 years. Cardiovascular failure (39%) and respiratory failure (35%) were the main diagnostic categories for admission; 50.7% of the patients needed mechanical ventilation, 44% echocardiogram, 13.5% bronchoscopy and 10.3% hemodynamic evaluation with Swan-Ganz catheter. These are patients with high mean values of severity scoring systems, ICU mortality (27%) and Hospital mortality (37.6%). APACHE II, SAPS I and TISS on day one of admission and maximum value over a 24 hour period of two multiple organ failure systems-MOF and OSF were validated in this population and were good outcome predictors.


Subject(s)
Intensive Care Units/organization & administration , Intensive Care Units/statistics & numerical data , Adolescent , Adult , Aged , Aged, 80 and over , Child , Female , Humans , Male , Middle Aged , Severity of Illness Index , Survival Analysis
12.
Acta Med Port ; 5(8): 425-8, 1992 Sep.
Article in Portuguese | MEDLINE | ID: mdl-1442191

ABSTRACT

OBJECTIVE: to characterize and to assess in terms of severity the surgical and trauma patients admitted to a medical intensive care unit (ICU). DESIGN: retrospective study base on clinical records and the ICU computerized database. SETTING: the medical ICU of a tertiary hospital. RESULTS: of the 2468 patients admitted to the ICU in 1989, 289 (11.7%) were surgical or trauma ones. The more frequent reasons for admission were: the need for mechanical ventilation, metabolic problems, and depression of consciousness. Of these 289 patients, 48.1% required mechanical ventilation, 14.9 hemodialysis; 4.8% had a pulmonary artery catheter inserted. Mean APACHE II, TISS and MOF scores were high (20.09 +/- 9.29, 24.17 +/- 11.45 and 5.4 +/- 3.59); they were determined in 79.2, 88.2 and 43.9% of patients respectively. Both APACHE and TISS scores were correlated with mortality. When compared with medical patients, surgical/trauma ones although younger (52.9 +/- 20.7 years versus 55.9 +/- 20.2, p = 0.00152), had a longer mean stay in the ICU (7.63 +/- 12.7 days v. 3.64 +/- 7.61, p = 0.0001), and a higher mortality (also in the ICU) (28.7 v. 16.7, p = 0.0005. COMMENTS: these are seriously ill patients, who are frequently referred to the ICU in late stages of clinical evolution. We propose they should be closely followed, from the earliest possible stage, by medical-surgical teams, in order to benefit from a multidisciplinary approach.


Subject(s)
Critical Care , Postoperative Complications/therapy , Wounds and Injuries/therapy , Adult , Aged , Female , Humans , Intensive Care Units , Male , Middle Aged , Portugal , Postoperative Care , Postoperative Complications/mortality , Retrospective Studies , Severity of Illness Index , Wounds and Injuries/mortality
13.
Acta Med Port ; 5(7): 365-8, 1992 Jul.
Article in Portuguese | MEDLINE | ID: mdl-1442180

ABSTRACT

The authors present a retrospective study of medical records of patients with lung cancer, admitted at the Service 1 of Internal Medicine of Santo António dos Capuchos Hospital during a 12 year period (1978-1989). Of the 112 selected patients, 50% had histologic diagnosis, the remaining had strong clinical radiographic, endoscopic and/or autopsic evidence of pulmonary malignancy or malignant cytology in sputum, bronchial secretions or pleural fluid. The clinical symptoms and means of diagnosis are presented and the advanced stage of the disease, at admission, the problems concerning the histologic diagnosis and the high mortality rate (55.4%) are emphasized.


Subject(s)
Lung Neoplasms , Female , Hospital Departments , Humans , Internal Medicine , Lung Neoplasms/diagnosis , Lung Neoplasms/pathology , Male , Middle Aged , Portugal , Retrospective Studies
14.
Acta Med Port ; 5(3): 115-8, 1992 Mar.
Article in Portuguese | MEDLINE | ID: mdl-1595377

ABSTRACT

A retrospective analysis was made concerning 1340 admissions to a multidisciplinary Intensive Care Unit over four years (1986-1989), because of acute poisoning. In 666 patients occurred 735 drug overdoses and in 674 patients, 691 non-drug intoxications. The drugs with main action in central nervous system were the most frequent in drug overdoses and the organophosphates insecticides in the non-drug intoxications. During the considered period there was an absolute and relative fall in the number of admissions for acute poisoning (480 vs 244, 15.1% vs 9.9%). The patients admitted were 698 men (289 in drug-overdoses and 409 in non-drug group) with a statistically significant difference between the type of intoxication and sex (p less than 0.001). Age mean was 40.2 +/- 19.6 years, almost the same in the two groups of intoxications. The peak incidence occurred from March to October. From the hospital area of Lisbon came 814 patients and outside of Lisbon 495 patients. The mean duration of stay in the ICU was 3.90 +2- 6.15 days, being 2.71 +/- 3.80 in the drug overdoses and 5.08 +/- 7.62 in non-drug intoxications (p less than 0.001). From the therapeutic measures we emphasize mechanical ventilation (29.5%), total parenteral nutrition (18.5%), dialysis (2.9%), Swan-Ganz catheter (2.8%) and pacemaker (1.2%). The mortality rate was 13.7%, higher in non-drug intoxications (23.0%) than in drug overdoses (4.4%) (p less than 0.0001).


Subject(s)
Intensive Care Units/statistics & numerical data , Poisoning/epidemiology , Adolescent , Adult , Age Factors , Aged , Aged, 80 and over , Child , Child, Preschool , Drug-Related Side Effects and Adverse Reactions , Female , Humans , Infant , Male , Middle Aged , Poisoning/etiology , Poisoning/therapy , Retrospective Studies , Sex Factors , Time Factors
15.
Biomed Pharmacother ; 44(8): 435-7, 1990.
Article in English | MEDLINE | ID: mdl-2271742

ABSTRACT

Prolonged exposure to hyperoxia in order to compensate for inefficient ventilation can lead to progressive pulmonary damage and death. Since pulmonary macrophages control bacterial and viral penetration, we studied the effect of hyperoxia on pulmonary alveolar macrophages from newborn and adult rats, kept in air or in a 95% normobaric oxygen atmosphere. The viability of pulmonary alveolar macrophages in bronchoalveolar lavages of newborn rats after 3 d in oxygen was significantly lower than that of newborn rats after 3 days in air. The functional capacity, as measured by the phagocytosis of Candida was similarly affected and these observations mays explain why infections develop. Adult rat macrophages were not sensitive to hyperoxia.


Subject(s)
Lung/drug effects , Oxygen/toxicity , Animals , Dose-Response Relationship, Drug , Female , Lung/immunology , Macrophages/immunology , Male , Oxygen/administration & dosage , Phagocytosis/drug effects , Rats , Rats, Inbred Strains , Respiratory Insufficiency/therapy
16.
Phys Rev A Gen Phys ; 40(3): 1262-1278, 1989 Aug 01.
Article in English | MEDLINE | ID: mdl-9902259
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