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1.
J Gerontol A Biol Sci Med Sci ; 74(Suppl_1): S13-S20, 2019 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-31529019

RESUMO

BACKGROUND: The 122 years and 164 days age claim of Jeanne Calment, the world oldest person who died in 1997, is the most thoroughly validated age claim. Recently the claim that families Calment and Billot organized a conspiracy concerning tax fraud based on identity fraud between mother and daughter gained international media attention. METHODS: Here, we reference the original components of the validation as well as additional documentation to address various claims of the conspiracy theory and provide evidence for why these claims are based on inaccurate facts or unrelated to the death of Yvonne Billot-Calment, the daughter of Jeanne Calment, in 1934. RESULTS: Also, countering the contention that the occurrence of a 122 year old person is statistically impossible, mathematical models are presented which also supports the hypothesis that though extremely rare, as would be expected for the oldest person ever, Jeanne Calment's age claim is plausible. CONCLUSIONS: In total, the quality of the investigation supporting the claim of conspiracy as well as the mathematical analysis aiming to back it do not reach the level expected for a scientific publication.


Assuntos
Confiabilidade dos Dados , Expectativa de Vida , Idoso de 80 Anos ou mais , Feminino , França , Humanos , Modelos Teóricos
2.
Nat Commun ; 10(1): 264, 2019 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-30651568

RESUMO

Permafrost warming has the potential to amplify global climate change, because when frozen sediments thaw it unlocks soil organic carbon. Yet to date, no globally consistent assessment of permafrost temperature change has been compiled. Here we use a global data set of permafrost temperature time series from the Global Terrestrial Network for Permafrost to evaluate temperature change across permafrost regions for the period since the International Polar Year (2007-2009). During the reference decade between 2007 and 2016, ground temperature near the depth of zero annual amplitude in the continuous permafrost zone increased by 0.39 ± 0.15 °C. Over the same period, discontinuous permafrost warmed by 0.20 ± 0.10 °C. Permafrost in mountains warmed by 0.19 ± 0.05 °C and in Antarctica by 0.37 ± 0.10 °C. Globally, permafrost temperature increased by 0.29 ± 0.12 °C. The observed trend follows the Arctic amplification of air temperature increase in the Northern Hemisphere. In the discontinuous zone, however, ground warming occurred due to increased snow thickness while air temperature remained statistically unchanged.

3.
IEEE Trans Biomed Circuits Syst ; 12(6): 1289-1300, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30387742

RESUMO

This paper presents the EcoChip, a new system based on the state-of-the-art electro-chemical impedance (EIS) technologies allowing the growth of single strain organisms isolated from northern habitats. This portable system is a complete and autonomous wireless platform designed to monitor and cultivate microorganisms directly sampled from their natural environment, particularly from harsh northern environments. Using 96-well plates, the EcoChip can be used in the field for real-time monitoring of bacterial growth. Manufactured with high-quality electronic components, this new EIS monitoring system is designed to function at a low excitation voltage signal to avoid damaging the cultured cells. The high-precision calibration network leads to high-precision results, even in the most limiting contexts. Luminosity, humidity, and temperature can also be monitored with the addition of appropriate sensors. Access to robust data storage systems and power supplies is an obvious limitation for northern research. That is why the EcoChip is equipped with a flash memory that can store data over long periods of time. To resolve the power issue, a low-power micro-controller and a power management unit control and supply all electronic building blocks. Data stored in the EcoChip's flash memory can be transmitted through a transceiver whenever a receiver is located within the functional transmission range. In this paper, we present the measured performance of the system, along with results from laboratory tests in vitro and from two field tests. The EcoChip has been utilized to collect bio-environemental data in the field from the northern soils and ecosystems of Kuujjuarapik and Puvirnituq, during two expeditions, in 2017 and 2018, respectively. We show that the EcoChip can effectively carry out EIS analyses over an excitation frequency ranging from 750 Hz to 10 kHz with an accuracy of 2.35%. The overall power consumption of the system was 140.4 mW in normal operating mode and 81 µW in sleep mode. The proper development of the isolated bacteria was confirmed through deoxyribonucleic acid sequencing, indicating that bacteria thrive in the EcoChip's culture wells while the growing conditions are successfully gathered and stored.


Assuntos
Técnicas Bacteriológicas/instrumentação , Monitoramento Ambiental/instrumentação , Microbiologia do Solo , Microbiologia da Água , Bacillus subtilis/genética , Bacillus subtilis/isolamento & purificação , Bacillus subtilis/fisiologia , Clima , DNA Bacteriano/análise , Espectroscopia Dielétrica/instrumentação , Desenho de Equipamento , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Escherichia coli/fisiologia
4.
Sci Total Environ ; 581-582: 161-173, 2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-28062107

RESUMO

Cryosols contain ~33% of the global soil organic carbon. Cryosol warming and permafrost degradation may enhance the CO2 release to the atmosphere through the microbial decomposition. Despite the large carbon pool, the permafrost carbon feedback on the climate remains uncertain. In this study, we aimed at better understanding the diurnal evolution of the temperature sensitivity of CO2 efflux in Cryosols. A Histic Cryosol and a Turbic Cryosol were instrumented in tussock tundra ecosystems near Salluit (Nunavik, Canada). Open top chambers were installed during summer 2011 and the ground temperature, the soil moisture and meteorological variables were recorded hourly while the ecosystem respiration was measured three times per day every second day with opaque and closed dynamic chambers in control and warm stations. Despite warmer conditions, the average CO2 efflux at the control stations at the Histic site (1.29±0.45µmolCO2m-2s-1) was lower than at the Turbic site (2.30±0.74µmolCO2m-2s-1). The increase in CO2 efflux with warming was greater in the Histic Cryosol (~39%) than in the Turbic Cryosol (~16%). Our study showed that the temperature sensitivity of the ecosystem respiration evolved during the day and decreased with the experimental warming. Both sites exhibited diurnal hysteresis loops between CO2 efflux and the soil surface temperature. The width of hysteresis loops increased with the solar radiation and decreased along the growing season. We developed simple linear models that took into account the diurnal evolution of the temperature sensitivity of CO2 efflux and we estimated the seasonal cumulative carbon release to the atmosphere. The calculation using solely diurnal measurements significantly differed from the seasonal carbon release modelled hourly. Our study highlighted that the time of the day when measurements are performed should be taken into account to accurately estimate the seasonal carbon release from tundra ecosystems.

5.
Knee Surg Sports Traumatol Arthrosc ; 14(7): 629-36, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16341690

RESUMO

We reviewed 33 patients who underwent anterior cruciate ligament (ACL) reconstruction using a two-bundle, four-tunnel technique. The posterolateral bundle (PLB) and anteromedial bundle (AMB) were individually reconstructed with gracilis and semitendinosus tendon auto-grafts, respectively, using separate tibial and femoral tunnels. At final follow-up (24 months post surgery, range 18-31) the International Knee Documentation Committee's (IKDC) objective final evaluation scores were 69 A, 19 B, 12% C. The mean global subjective IKDC score was 86+/-12 points. Ninety-four percent of the patients had returned to sport after an average of 9 months following surgery and 75% returned to their preinjury sporting level. One patient had suffered a graft rupture as a result of a further sports injury. Eighty-four percent of the patients had a negative pivot shift (IKDC A), 9% a glide (IKDC B), and 6% a "clunk" (IKDC C). The mean postoperative side-to-side laxity, measured with KT1000 arthrometry at manual maximum, was 0.9 mm (SD 1.9). Eighty-one percent of the patients had less than 3 mm difference, with only one patient having greater than 5 mm. Our early experience with this new technique appears to demonstrate satisfactory results that are at least equivalent to other techniques and show an apparent trend towards improved control of anterior laxity.


Assuntos
Ligamento Cruzado Anterior/cirurgia , Fêmur/cirurgia , Procedimentos Ortopédicos/métodos , Tendões/transplante , Tíbia/cirurgia , Adolescente , Adulto , Ligamento Cruzado Anterior/fisiopatologia , Lesões do Ligamento Cruzado Anterior , Artrometria Articular , Feminino , Seguimentos , Humanos , Instabilidade Articular/diagnóstico por imagem , Instabilidade Articular/fisiopatologia , Articulação do Joelho/diagnóstico por imagem , Articulação do Joelho/fisiopatologia , Articulação do Joelho/cirurgia , Masculino , Radiografia , Amplitude de Movimento Articular/fisiologia , Recuperação de Função Fisiológica/fisiologia , Transplante Autólogo , Resultado do Tratamento
6.
Knee ; 13(2): 127-31, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16352431

RESUMO

Bone tunnel enlargement following anterior cruciate ligament (ACL) reconstruction can complicate revision surgery. This study compared postoperative tibial tunnel widening in patients who underwent arthroscopically assisted, single-incision, four-strand hamstring ACL reconstruction using a poly-L-lactic acid/hydroxyapatite blend (PLLA+HA) bioabsorbable interference screw for tibial fixation, with those in whom a plain poly-L-lactic acid (PLLA) screw was used. Thirty-four patients (13 with PLLA+HA tibial interference screw fixation and 21 with plain PLLA tibial interference screws) underwent a spiral CT scan to assess maximum tibial tunnel cross-sectional area at an average of 28.7 months follow-up. An assessment of tunnel wall sclerosis adjacent to the screw (cortication) was also made. The two groups were well matched for age, sex and graft diameters. Mean tibial tunnel enlargement in patients with PLLA+HA screws was 29.9% at average 30.9 months follow-up compared with 46% in patients with plain PLLA screw at an average 26.5 months follow-up (p=0.03). The tunnel wall adjacent to the screw appeared corticated in only 21% of patients with PLLA+HA screws (p=0.02) compared with 73% of patients with PLLA screws. The blending of HA with PLLA appears to reduce postoperative tunnel widening, and the reduced tunnel wall sclerosis seen postoperatively may indicate improved screw incorporation.


Assuntos
Implantes Absorvíveis , Ligamento Cruzado Anterior/cirurgia , Materiais Biocompatíveis , Parafusos Ósseos , Durapatita , Ácido Láctico , Polímeros , Adulto , Ligamento Cruzado Anterior/diagnóstico por imagem , Lesões do Ligamento Cruzado Anterior , Artroscopia , Feminino , Seguimentos , Humanos , Masculino , Osseointegração , Poliésteres , Radiografia , Estudos Retrospectivos , Tíbia/diagnóstico por imagem , Tíbia/cirurgia
7.
Exp Gerontol ; 38(4): 361-5, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12670622

RESUMO

This work, based on a matched case-control design, tests the assumption that centenarians were conceived by parents younger than the parents of individuals who had lifespan close to mean life duration. The centenarians are paired with controls of the same sex, born at the same place and at the same time in order to avoid traditional biases related to mortality peaks or secular trend of increase in life expectancy. The parental age at the time of the birth registration of 320 centenarians born in France between 1875 and 1890 and deceased between 1990 and 1999 is collected, as well as the one of 603 controls of the same sex whose births were recorded immediately before or after those of the future centenarians on the birth registers of the cities concerned. No difference is found between the parental age of parents of centenarians and of controls. In particular, no difference is found for females. Recent studies showed--from genealogical data--that the life expectancy of a female would be much reduced if her father was old at the time of her conception. Our study does not indicate a negative effect of a higher paternal age on the longevity of daughters.


Assuntos
Envelhecimento/fisiologia , Longevidade , Idade Materna , Idade Paterna , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Feminino , França , Humanos , Masculino
8.
Presse Med ; 32(8): 360-4, 2003 Mar 01.
Artigo em Francês | MEDLINE | ID: mdl-12712684

RESUMO

THE DEVELOPMENT OF STUDIES ON CENTENARIANS: In a spectacular context of increase in the number of centenarians and of emergence of super-centenarians (110 years old and over), large studies on the health of these very old populations were set up in France at the beginning of the 1990s. A HETEROGENIC POPULATION: The results of these studies make it possible to describe centenarians as a heterogenic population mainly composed of women. Their functional health, their sensory performance, their limitations in daily life activities, their social and family integration, their cognitive functioning, are very varied. They appear as robust individuals who have triumphed over the hardships they have lived. LONGEVITY AND DEMENTIA: The French study has revealed that 35% of the women and 58% of the men are free from any suspicion of dementia according to Pfeiffer's screening test, which is encouraging if we consider the disastrous scenarios which could have been forecasted.


Assuntos
Idoso de 80 Anos ou mais , Nível de Saúde , Atividades Cotidianas , Idoso , Cognição , Demência , Relações Familiares , Feminino , França , Humanos , Masculino , Apoio Social
9.
Arthroscopy ; 18(3): 232-7, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11877607

RESUMO

PURPOSE: The purpose of this study was to determine the outcome of 200 anterior cruciate ligament (ACL) reconstructions using hamstring tendons. TYPE OF STUDY: This is a case series reporting on 200 endoscopic procedures for reconstruction of the ACL. METHODS: This study included patients over 18 years old with a healthy controlateral knee, intact posterior cruciate ligament, and without any peripheral surgical procedure or cartilage injury. Patients having undergone prior ligament reconstruction were excluded from the study. The minimum follow-up was 1 year. Clinical review allowed for documentation of International Knee Documentation Committee (IKDC), KT-1000 arthrometer laxity measurement, and isokinetic dynamometric analysis. RESULTS: Quadriceps and hamstring muscle strength loss was less than 17%. At review, overall IKDC evaluation found that 50% of patients graded A, 44% graded B, and 6% were C or D. The differential anterior laxity was graded A for 157 patients with a median of 1 mm. Of the 113 high-performance athletes, 98 (86%) had resumed a preinjury level of sporting activity. CONCLUSIONS: Endoscopic reconstruction using 4-strand hamstring autograft may be considered safe, reliable, and reproducible. Preliminary outcome is fulfilling and this technique corresponds completely to therapeutic fields regarding ACL reconstructions.


Assuntos
Ligamento Cruzado Anterior/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Tendões/transplante , Adulto , Lesões do Ligamento Cruzado Anterior , Artroscopia , Parafusos Ósseos , Teste de Esforço , Feminino , Seguimentos , Humanos , Fixadores Internos , Traumatismos do Joelho/complicações , Traumatismos do Joelho/diagnóstico , Traumatismos do Joelho/cirurgia , Masculino , Metais/uso terapêutico , Esportes , Resultado do Tratamento
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