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1.
Ann Sci ; 78(2): 162-196, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33646924

RESUMO

We are interested in the case of Friedrich Christoph Mayer, who in the 1720s, while at the Imperial Academy of Sciences in St. Petersburg (in Latin Academiae scientiarum imperialis Petropolitanae), developed a system of the aurora borealis, as well as a mathematical method for calculating the height of the aurora from the geometrical characteristics of the auroral arc. Mayer, encountering a major contradiction in his system which placed the aurora at the height of the clouds, whereas his mathematical method led to an altitude a hundred times higher, never applied his method to concrete cases to deduce the height of the aurora, and quickly lost interest in their detailed description, a task that was nevertheless assigned to him at the St. Petersburg Observatory. Jean-Jacques Dortous de Mairan suggests that Mayer's abandonment was due to his lack of confidence in observations. We set Mayer's case against that of Leonhard Euler who, working with Mayer and being aware of the great height of the aurora, later developed a system of the aurora borealis that was compatible with the observational fact. We put forward possible hypotheses to explain Mayer's disinterest in observing the aurora and in the mathematical method he himself had developed.


Assuntos
Astronomia/história , Atmosfera , Meio Ambiente Extraterreno , Alemanha , História do Século XVIII , Modelos Teóricos , Federação Russa
2.
J Urban Health ; 92(6): 1105-16, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26446875

RESUMO

Commercial sex workers (CSWs) in the Russian Federation are at high risk of HIV infection and transmission as a result of unsafe sexual and injecting behaviors. Their clients might be at increased risk of acquiring HIV; however, little is known about the population of men purchasing sex services. This study aims to investigate factors associated with a history of purchasing sex services by men in Saint Petersburg and Leningrad Oblast, Russian Federation. Data were collected as part of a cross-sectional study offering free anonymous rapid HIV testing in Saint Petersburg and Leningrad Oblast in 2014; in total, 3565 men aged 18 years and older provided information about their behaviors associated with risk of acquiring HIV during face-to-face interviews. Prevalence of CSW use in our study was 23.9%. Multivariable analyses using log-binomial regression were stratified by self-reported HIV testing during the 12 months preceding the study interview. In both strata, older age, multiple sex partners, and a history of sex with an injection drug user (IDU) were associated with an elevated prevalence ratio (PR) for history of purchasing sex services, although the strength of the association differed by strata. Among men who reported recent HIV testing, condom use (PR = 1.22, 90% confidence interval (CI) 1.0, 1.48) was associated with a history of purchasing sex services, and among men who did not report recent HIV testing, having a consistent sex partner was associated with purchasing sex services (PR = 1.23, 90% CI 1.1, 1.37). The high prevalence of CSW service use and associations found in this study raise serious concerns about potential for sexual HIV transmission and should be investigated more closely.


Assuntos
Trabalho Sexual/estatística & dados numéricos , Comportamento Sexual/estatística & dados numéricos , Parceiros Sexuais , Sexo sem Proteção/estatística & dados numéricos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Humanos , Masculino , Pessoa de Meia-Idade , Assunção de Riscos , Federação Russa , Fatores Socioeconômicos , Fatores de Tempo , Adulto Jovem
3.
Viruses ; 14(12)2022 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-36560752

RESUMO

The HIV/AIDS epidemic in Russia is among the fastest growing in the world. HIV epidemic burden is non-uniform in different Russian regions and diverse key populations. An explosive epidemic has been documented among people who inject drugs (PWID) starting from the mid-1990s, whereas presently, the majority of new infections are linked to sexual transmission. Nationwide, HIV sub-subtype A6 (previously called AFSU) predominates, with the increasing presence of other subtypes, namely subtype B and CRF063_02A. This study explores HIV subtype B sequences from St. Petersburg, collected from 2006 to 2020, in order to phylogenetically investigate and characterize transmission clusters, focusing on their evolutionary dynamics and potential for further growth, along with a socio-demographic analysis of the available metadata. In total, 54% (107/198) of analyzed subtype B sequences were found grouped in 17 clusters, with four transmission clusters with the number of sequences above 10. Using Bayesian MCMC inference, tMRCA of HIV-1 subtype B was estimated to be around 1986 (95% HPD 1984-1991), whereas the estimated temporal origin for the four large clusters was found to be more recent, between 2001 and 2005. The results of our study imply a complex pattern of the epidemic spread of HIV subtype B in St. Petersburg, Russia, still in the exponential growth phase, and in connection to the men who have sex with men (MSM) transmission, providing a useful insight needed for the design of public health priorities and interventions.


Assuntos
Infecções por HIV , HIV-1 , Minorias Sexuais e de Gênero , Masculino , Humanos , Homossexualidade Masculina , Infecções por HIV/epidemiologia , HIV-1/genética , Teorema de Bayes , Federação Russa/epidemiologia , Filogenia
4.
Viruses ; 14(5)2022 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-35632653

RESUMO

Introduction. Since the detection of the first COVID-19 patient, 2 years have passed, during which more than 287,862,000 people have fallen ill globally, of which about 1.9% died. The implementation of SARS-CoV-2 control programs required efforts from almost all countries. An important direction in the fight against COVID-19 has been the formation of herd immunity, the main tool for managing the pandemic. Study goal. The aim of the study was to assess the seroprevalence of antibodies (Abs) to SARS-CoV-2 nucleocapsid (Nc) and receptor binding domain (RBD) in the St. Petersburg population during the COVID-19 pandemic. Materials and methods. A longitudinal cohort randomized monitoring study of Ab seroprevalence (SARS-CoV-2 Nc, RBD) was organized and conducted according to a unified methodology developed by Rospotrebnadzor with the participation of the St. Petersburg Pasteur Institute. For this purpose, a cohort was formed of 1000 volunteers who participated in all five stages of seromonitoring. The cohort was divided into seven age groups: 1−17; 18−29; 30−39; 40−49; 50−59; 60−69; 70; and older (70+) years. Seropositivity levels (Nc, RBD) were assessed by quantitative and qualitative enzyme immunoassays. During the second year of monitoring, some volunteers were vaccinated with the GamCOVIDVac (84%) or EpiVacCorona (11.6%) vaccines approved in Russia. Statistical processing was carried out using Excel 2010. Confidence intervals for shares and percentages (95% CI) were calculated using the method of A. Wald and J. Wolfowitz with adjustment (A. Agresti, B.A. Coull). The statistical significance of differences was calculated by z-test, using the appropriate online calculator (p < 0.05) unless indicated. Results. There was a trend toward an increase in Nc seropositivity in stages 1−3 of seromonitoring, with a decrease in stages 4−5 among children and adults. The share of RBD seropositive steadily increased during all five stages of seromonitoring. The most frequent finding was low anti-RBD Abs levels (22.6−220 BAU/mL). High Ab levels were recorded statistically significantly less frequently. Asymptomatic forms were observed in 84−88% of SARS-CoV-2 seropositive volunteers. By the fifth stage of monitoring, this indicator significantly decreased to 69.8% (95% CI: 66.1−73.4). The monitoring revealed a statistically significant increase in anti-RBD Abs alongside a statistically significant decrease in the proportion of Nc seropositives. This dynamic was especially characteristic of persons vaccinated with GamCOVIDVac. Conclusion. Prior to the use of specific vaccines, a seroprevalence of anti-Nc Abs was noted. After the introduction of the GamCOVIDVac vaccine in adults, a decrease in the level of anti-Nc Abs was noted due to an increase in the proportion of RBD seropositive persons.


Assuntos
COVID-19 , Vacinas Virais , Adolescente , Anticorpos Antivirais , COVID-19/epidemiologia , Vacinas contra COVID-19 , Criança , Pré-Escolar , Estudos de Coortes , Humanos , Lactente , Pandemias , SARS-CoV-2 , Estudos Soroepidemiológicos , Vacinas Sintéticas
5.
Talanta ; 206: 119759, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31514836

RESUMO

The year 2019 marks the 150th year of the founding of analytical chemistry department at St. Petersburg State University and of the founding of the periodic table of chemical elements as proposed by Professor Dmitry Mendeleev. 2019 has been decreed by chemists as the "International Year of the Periodic Table" in celebration of these historical events. A celebration marking this anniversary was held at the university on March 1. This historical account will recount the early days of the department and Mendeleev's development of the periodic table, and then highlight some of the major analytical contributions of the department.

6.
Top Cogn Sci ; 12(1): 417-432, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31899591

RESUMO

The St. Petersburg paradox is a centuries-old philosophical puzzle concerning a lottery with infinite expected payoff for which people are only willing to pay a small amount to play. Despite many attempts and several proposals, no generally accepted resolution is yet at hand. In this work, we present the first resource-rational, process-level explanation of this paradox, demonstrating that it can be accounted for by a variant of normative expected utility valuation which acknowledges cognitive limitations. Specifically, we show that Nobandegani et al.'s (2018) metacognitively rational model, sample-based expected utility (SbEU), can account for major experimental findings on this paradox. Crucially, our resolution is consistent with two empirically well-supported assumptions: (a) People use only a few samples in probabilistic judgments and decision-making, and (b) people tend to overestimate the probability of extreme events in their judgment. Our work seeks to understand the St. Petersburg gamble as a particularly risky gamble whose process-level explanation is consistent with a broader process-level model of human decision-making under risk.


Assuntos
Tomada de Decisões , Modelos Psicológicos , Recompensa , Assunção de Riscos , Adulto , Tomada de Decisões/fisiologia , Humanos
7.
J Homosex ; 66(7): 937-969, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-29883282

RESUMO

This article explores queer sexual policing in late Imperial St. Petersburg (c.1900-1917). The focus is on the street-level constables who bore the principal responsibility for policing male homosexual offenses in the city's public and semi-public spaces. This emphasis on the street-level policing of homosexuality contrasts with other discussions of gay urban history and the oppression of queer men by the authorities. The article draws on new evidence from precinct-level police archives to complement and challenge previous discussions of queer sexual policing in the Imperial capital. By taking the fate of queer men in an autocratic city, this article refines our understanding of the ways in which homosexual practices and identities emerged in modern times. Specifically, it builds on Michel Foucault's descriptions of constables as "arbiters of illegalities," where the term arbiter suggests rule-based and yet discretionary coercion. Here, the influential model of disciplinary policing of sexuality is complemented by an emphasis on the role of discretionary power in the history of homosexuality.


Assuntos
Homossexualidade Masculina/história , Polícia/história , Minorias Sexuais e de Gênero/história , História do Século XX , Humanos , Masculino , Federação Russa , Delitos Sexuais/história , Delitos Sexuais/legislação & jurisprudência , Minorias Sexuais e de Gênero/legislação & jurisprudência
8.
J R Coll Physicians Edinb ; 47(1): 102-109, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28569293

RESUMO

Rhubarb was grown and used throughout China for thousands of years. It then found its way to St Petersburg where the Romanovs developed a flourishing trade in the plant to the rest of Europe. James Mounsey, a physician to the Tsar, brought back seeds from Russia to Scotland at considerable risk to himself. He passed some of the seeds to Alexander Dick and John Hope. Both these physicians then grew rhubarb at Prestonfield and the Botanic Garden (both in Edinburgh), respectively. Eventually rhubarb, in the form of Gregory's powder, became a common and popular medicine throughout the UK.


Assuntos
Fitoterapia/história , Preparações de Plantas/história , Rheum , Comércio/história , Jardinagem/história , Grécia Antiga , História do Século XVIII , História do Século XIX , História Antiga , Humanos , Medicina Arábica/história , Preparações de Plantas/intoxicação , Preparações de Plantas/uso terapêutico , Escócia
9.
Soc Sci Med ; 130: 154-61, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25703668

RESUMO

Experiences of stigma are often associated with negative mental and physical health outcomes. The present work tested the associations between stigma and health-related outcomes among people with HIV who inject drugs in Kohtla-Järve, Estonia and St. Petersburg, Russia. These two cities share some of the highest rates of HIV outside of sub-Saharan Africa, largely driven by injection drug use, but Estonia has implemented harm reduction services more comprehensively. People who inject drugs were recruited using respondent-driven sampling; those who indicated being HIV-positive were included in the present sample (n = 381 in St. Petersburg; n = 288 in Kohtla-Järve). Participants reported their health information and completed measures of internalized HIV stigma, anticipated HIV stigma, internalized drug stigma, and anticipated drug stigma. Participants in both locations indicated similarly high levels of all four forms of stigma. However, stigma variables were more strongly associated with health outcomes in Russia than in Estonia. The St. Petersburg results were consistent with prior work linking stigma and health. Lower barriers to care in Kohtla-Järve may help explain why social stigma was not closely tied to negative health outcomes there. Implications for interventions and health policy are discussed.


Assuntos
Infecções por HIV/psicologia , Nível de Saúde , Saúde Mental , Estigma Social , Abuso de Substâncias por Via Intravenosa/psicologia , Adulto , Contagem de Linfócito CD4 , Cidades , Estudos Transversais , Depressão/epidemiologia , Escolaridade , Estônia/epidemiologia , Feminino , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Política de Saúde , Humanos , Masculino , Federação Russa/epidemiologia , Comportamento Sexual , Abuso de Substâncias por Via Intravenosa/epidemiologia
10.
Hastings Cent Rep ; 16(6): 3, 1986 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11643946

RESUMO

KIE: Lewis summarizes the findings of a St. Petersburg Times poll asking readers to comment on four hypothetical ethical dilemmas in medicine. Opinions also were solicited from a panel of three physicians and a philosopher. The cases involved a choice among three patients for a liver transplant; a request by the wife of a comatose patient that her husband's life support systems be removed; a decision about whether to perform life-saving surgery over a patient's objections; and a decision about whether an older pregnant woman should undergo amniocentesis and abort her fetus if it were diagnosed as having Down's syndrome. Over 900 readers responded to the poll, the results of which were published in the 6 Oct 1986 issue of the St. Petersburg Times together with the responses of the panel members.^ieng


Assuntos
Temas Bioéticos , Bioética , Opinião Pública , Aborto Eugênico , Estado Terminal , Eutanásia Passiva , Florida , Alocação de Recursos para a Atenção à Saúde , Humanos , Meios de Comunicação de Massa , Transplante de Órgãos , Seleção de Pacientes , Estado Vegetativo Persistente , Diagnóstico Pré-Natal , Transplante , Recusa do Paciente ao Tratamento
11.
Med Anthropol Q ; 10(1): 3-19, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8689443

RESUMO

The Catholic Church is the largest (and arguably the best organized) single denomination in the United States, and it has extensive holdings in the health care field. It therefore has a material stake in the current debate over health care reform, as well as a moral interest in a question touching on the ethics of resource distribution. The position of the church on health care is analyzed as a case study of how organized religion interacts with and attempts to influence social policy in a pluralistic society.


Assuntos
Catolicismo , Reforma dos Serviços de Saúde/tendências , Obrigações Morais , Política Pública , Religião e Medicina , Justiça Social , Valores Sociais , Capitalismo , Análise Custo-Benefício , Diversidade Cultural , Ética Médica , Governo Federal , Regulamentação Governamental , Reforma dos Serviços de Saúde/economia , Humanos , Comunicação Interdisciplinar , Competição em Planos de Saúde/economia , Competição em Planos de Saúde/tendências , Princípios Morais , Filosofia , Política , Secularismo , Estados Unidos , Populações Vulneráveis
12.
Healthc Technol Lett ; 1(3): 98-103, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26609386

RESUMO

Electrocardiogram (ECG) beat classification plays an important role in the timely diagnosis of the critical heart condition. An automated diagnostic system is proposed to classify five types of ECG classes, namely normal (N), ventricular ectopic beat (V), supra ventricular ectopic beat (S), fusion (F) and unknown (Q) as recommended by the Association for the Advancement of Medical Instrumentation (AAMI). The proposed method integrates the Stockwell transform (ST), a bacteria foraging optimisation (BFO) algorithm and a least mean square (LMS)-based multiclass support vector machine (SVM) classifier. The ST is utilised to extract the important morphological features which are concatenated with four timing features. The resultant combined feature vector is optimised by removing the redundant and irrelevant features using the BFO algorithm. The optimised feature vector is applied to the LMS-based multiclass SVM classifier for automated diagnosis. In the proposed technique, the LMS algorithm is used to modify the Lagrange multiplier, which in turn modifies the weight vector to minimise the classification error. The updated weights are used during the testing phase to classify ECG beats. The classification performances are evaluated using the MIT-BIH arrhythmia database. Average accuracy and sensitivity performances of the proposed system for V detection are 98.6% and 91.7%, respectively, and for S detections, 98.2% and 74.7%, respectively over the entire database. To generalise the capability, the classification performance is also evaluated using the St. Petersburg Institute of Cardiological Technics (INCART) database. The proposed technique performs better than other reported heartbeat techniques, with results suggesting better generalisation capability.

14.
Judgm Decis Mak ; 4(4): 256-272, 2009 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-24179560

RESUMO

The St. Petersburg Paradox is a famous economic and philosophical puzzle that has generated numerous conflicting explanations. To shed empirical light on this phenomenon, we examined subjects' bids for one St. Petersburg gamble with a real monetary payment. We found that bids were typically lower than twice the smallest payoff, and thus much lower than is generally supposed. We also examined bids offered for several hypothetical variants of the St. Petersburg Paradox. We found that bids were weakly affected by truncating the gamble, were strongly affected by repeats of the gamble, and depended linearly on the initial "seed" value of the gamble. One explanation, which we call the median heuristic, strongly predicts these data. Subjects following this strategy evaluate a gamble as if they were taking the median rather than the mean of the payoff distribution. Finally, we argue that the distribution of outcomes embodied in the St. Petersburg paradox is so divergent from the Gaussian form that the statistical mean is a poor estimator of expected value, so that the expected value of the St. Petersburg gamble is undefined. These results suggest that this classic paradox has a straightforward explanation rooted in the use of a statistical heuristic.

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