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2.
Front Big Data ; 5: 787421, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35496379

RESUMO

In this community review report, we discuss applications and techniques for fast machine learning (ML) in science-the concept of integrating powerful ML methods into the real-time experimental data processing loop to accelerate scientific discovery. The material for the report builds on two workshops held by the Fast ML for Science community and covers three main areas: applications for fast ML across a number of scientific domains; techniques for training and implementing performant and resource-efficient ML algorithms; and computing architectures, platforms, and technologies for deploying these algorithms. We also present overlapping challenges across the multiple scientific domains where common solutions can be found. This community report is intended to give plenty of examples and inspiration for scientific discovery through integrated and accelerated ML solutions. This is followed by a high-level overview and organization of technical advances, including an abundance of pointers to source material, which can enable these breakthroughs.

3.
Knee ; 22(5): 424-8, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25795544

RESUMO

BACKGROUND: Early failure in cemented total knee replacement (TKR) due to aseptic loosening is uncommon. A small number of early failures requiring revision were observed at one hospital due to observed cement-implant fixation failure. The purpose of this case series is to report and identify possible causes for these early failures. METHODS: Between May 2005 and December 2010, 3048 primary TKRs were performed over a five-year period of time by six surgeons. Two total knee systems were used during this period of time. Nine early failures were observed in eight patients. High viscosity cement (HVC) was used in all these cases. RESULTS: Aseptic loosening of the tibial component was observed in all nine early total knee failures. The high viscosity bone cement was noted to be non-adherent to the tibial trays at the time of revision surgery. HVC was used in all these cases. CONCLUSIONS: Properties of HVC may contribute to make it more susceptible to early failure in a small number of TKRs. HVC in total hip replacement (THR) has been associated with cement micro-fractures, cement debris generation and early implant failure. The mechanical properties of HVC may similarly contribute to early failure at the cement-implant interface in a small percentage TKRs.


Assuntos
Artroplastia do Joelho , Cimentos Ósseos , Prótese do Joelho/efeitos adversos , Falha de Prótese , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reoperação , Estudos Retrospectivos
5.
Ann Occup Hyg ; 49(7): 575-85, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15964881

RESUMO

A critical review of studies examining exposures to the various forms of silver was conducted to determine if some silver species are more toxic than others. The impetus behind conducting this review is that several occupational exposure limits and guidelines exist for silver, but the values for each depend on the form of silver as well as the individual agency making the recommendations. For instance, the American Conference of Governmental Industrial Hygienists has established separate threshold limit values for metallic silver (0.1 mg/m3) and soluble compounds of silver (0.01 mg/m3). On the other hand, the permissible exposure limit (PEL) recommended by the Occupational Safety and Health Administration and the Mine Safety and Health Administration and the recommended exposure limit set by the National Institute for Occupational Safety and Health is 0.01 mg/m3 for all forms of silver. The adverse effects of chronic exposure to silver are a permanent bluish-gray discoloration of the skin (argyria) or eyes (argyrosis). Most studies discuss cases of argyria and argyrosis that have resulted primarily from exposure to the soluble forms of silver. Besides argyria and argyrosis, exposure to soluble silver compounds may produce other toxic effects, including liver and kidney damage, irritation of the eyes, skin, respiratory, and intestinal tract, and changes in blood cells. Metallic silver appears to pose minimal risk to health. The current occupational exposure limits do not reflect the apparent difference in toxicities between soluble and metallic silver; thus, many researchers have recommended that separate PELs be established.


Assuntos
Exposição Ambiental/efeitos adversos , Compostos de Prata/toxicidade , Prata/toxicidade , Argiria/etiologia , Doença Crônica , Oftalmopatias/induzido quimicamente , Guias como Assunto , Humanos , Doenças Profissionais/induzido quimicamente , Exposição Ocupacional/efeitos adversos , Doenças Respiratórias/induzido quimicamente , Prata/efeitos adversos , Prata/metabolismo , Compostos de Prata/efeitos adversos , Compostos de Prata/metabolismo , Sociedades Médicas , Solubilidade , Estados Unidos
6.
J Occup Environ Hyg ; 1(9): 613-9, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15559333

RESUMO

National Institute for Occupational Safety and Health method 7703 is a portable field procedure for the analysis of workplace air filter samples for hexavalent chromium (CrVI) content immediately after the samples are collected. The field method prescribes CrVI extraction from air filter samples with an ammonium sulfate/ammonium hydroxide extraction buffer using ultrasonic extraction (UE). Strong anion-exchange solid-phase extraction (SAE-SPE) is then used to separate CrVI from trivalent chromium and other interferences. Portable spectrophotometric measurement of CrVI is then conducted using the 1,5-diphenylcarbazide (DPC) method. However, it has been found that the ammonium extraction buffer does not adequately bring insoluble CrVI compounds into solution during the UE process. Thus, it was deemed necessary to modify the field method so that it would provide acceptable recoveries for insoluble CrVI compounds. To this end, a more alkaline extraction solution--sodium carbonate/sodium bicarbonate buffer--was investigated. The modified procedure using the highly alkaline extraction solution was demonstrated to be compatible with SAE-SPE cartridges when determining insoluble CrVI in air filter samples. It was found that the carbonate/bicarbonate buffer was equally effective for complete dissolution of both insoluble and soluble forms of CrVI. Furthermore, the modified procedure met desired performance criteria established for air sampling and analytical methods.


Assuntos
Poluição do Ar em Ambientes Fechados/análise , Carcinógenos Ambientais/análise , Cromo/análise , Exposição Ocupacional , Local de Trabalho , Soluções Tampão , Monitoramento Ambiental/normas , Filtração , Humanos , National Institute for Occupational Safety and Health, U.S. , Sensibilidade e Especificidade , Solubilidade , Estados Unidos
7.
J Hazard Mater ; 102(1): 29-38, 2003 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-12963281

RESUMO

Two methods for measuring airborne lead using field-portable instruments have been developed by the National Institute for Occupational Safety and Health (NIOSH): Method 7702 uses X-ray fluorescence (XRF), and Method 7701 employs ultrasonic extraction (UE) followed by anodic stripping voltammetry (ASV). The two portable methods were evaluated at mining sites. Area air samples were collected throughout two mills where ore from nearby mines was processed; the primary constituent of the ore was lead sulfide (galena). The air samples were collected on 37 mm mixed cellulose ester membrane filters housed within plastic filter cassettes. At the end of the work shift, the cassettes were collected and taken to a room off-site for analysis by the two portable methods. The filter samples were first analyzed by XRF and then by UE/ASV. Calibration was verified on both instruments according to standard procedures. The samples were then sent for confirmatory analysis via flame atomic absorption spectrometry (FAAS) according to NIOSH Method 7082. Pairwise comparisons between the methods using the paired t-test showed no statistically significant differences between ASV and FAAS (P>0.05); however, the comparison between XRF and FAAS was statistically significant (P<0.05). The elevated lead concentrations reported by XRF relative to FAAS were likely the result of the ability of XRF to report total lead, including lead silicates. This form of lead is not liberated in the digestion process prior to FAAS analysis, and is therefore not detected by this method. Despite this discrepancy, lead concentrations measured by both portable technologies were found to be highly correlated with the laboratory method (R2>0.96), suggesting that they are suitable as screening methods for airborne lead at mining sites.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental/instrumentação , Chumbo/análise , Mineração , Humanos , Saúde Ocupacional , Sensibilidade e Especificidade , Espectrometria por Raios X , Espectrofotometria Atômica
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