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1.
Artigo em Inglês | MEDLINE | ID: mdl-38557405

RESUMO

BACKGROUND: Environmental exposures impact amyotrophic lateral sclerosis (ALS) risk and progression, a fatal and progressive neurodegenerative disease. Better characterization of these exposures is needed to decrease disease burden. OBJECTIVE: To identify exposures in the residential setting that associate with ALS risk, survival, and onset segment. METHODS: ALS and control participants recruited from University of Michigan completed a survey that ascertained exposure risks in the residential setting. ALS risk was assessed using logistic regression models followed by latent profile analysis to consider exposure profiles. A case-only analysis considered the contribution of the residential exposure variables via a Cox proportional hazards model for survival outcomes and multinomial logistic regression for onset segment, a polytomous outcome. RESULTS: This study included 367 ALS and 255 control participants. Twelve residential variables were associated with ALS risk after correcting for multiple comparison testing, with storage in an attached garage of chemical products including gasoline or kerosene (odds ratio (OR) = 1.14, padjusted < 0.001), gasoline-powered equipment (OR = 1.16, padjusted < 0.001), and lawn care products (OR = 1.15, padjusted < 0.001) representing the top three risk factors sorted by padjusted. Latent profile analysis indicated that storage of these chemical products in both attached and detached garages increased ALS risk. Although residential variables were not associated with poorer ALS survival following multiple testing corrections, storing pesticides, lawn care products, and woodworking supplies in the home were associated with shorter ALS survival using nominal p values. No exposures were associated with ALS onset segment. CONCLUSION: Residential exposures may be important modifiable components of the ALS susceptibility and prognosis exposome.


Assuntos
Esclerose Lateral Amiotrófica , Exposição Ambiental , Fenótipo , Humanos , Esclerose Lateral Amiotrófica/epidemiologia , Esclerose Lateral Amiotrófica/mortalidade , Feminino , Masculino , Michigan/epidemiologia , Estudos de Casos e Controles , Exposição Ambiental/efeitos adversos , Exposição Ambiental/estatística & dados numéricos , Pessoa de Meia-Idade , Idoso , Fatores de Risco , Adulto
2.
Heliyon ; 10(8): e29496, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38681590

RESUMO

The woodworking applications are a fast-growing field that aims to create advanced coatings with superior wear resistance, reduced friction, and robust corrosion protection. Chromium silicon carbonitride (CrSiCN) coatings have emerged as a promising solution that offers a unique combination of properties ideal for various industrial applications. The C/N ratio significantly influences the coatings' mechanical and tribological properties. By optimizing the C/N ratio, this research aims to reveal new insights for CrSiCN coatings, enhancing their application in environments that require durability, efficiency, and longevity. In this paper, the effect of the C/N ratio on the structural, mechanical, and corrosion resistance of CrSiCN coatings deposited by cathodic arc evaporation on different steel substrates was studied. The main purpose was to enhance the mechanical and anticorrosion properties of the CrSiCN coatings and to select the optimum parameters for the deposition of layers with superior properties. The results showed that the final properties can be tailored by choosing specific deposition conditions. In this case, the C/N ratio proved to be critical since coatings with higher carbon content presented enhanced corrosion resistance, being able to withstand operating conditions similar to real-life.

3.
Sensors (Basel) ; 24(4)2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38400250

RESUMO

The advancement of machine learning in industrial applications has necessitated the development of tailored solutions to address specific challenges, particularly in multi-class classification tasks. This study delves into the customization of loss functions within the eXtreme Gradient Boosting (XGBoost) algorithm, which is a critical step in enhancing the algorithm's performance for specific applications. Our research is motivated by the need for precision and efficiency in the industrial domain, where the implications of misclassification can be substantial. We focus on the drill-wear analysis of melamine-faced chipboard, a common material in furniture production, to demonstrate the impact of custom loss functions. The paper explores several variants of Weighted Softmax Loss Functions, including Edge Penalty and Adaptive Weighted Softmax Loss, to address the challenges of class imbalance and the heightened importance of accurately classifying edge classes. Our findings reveal that these custom loss functions significantly reduce critical errors in classification without compromising the overall accuracy of the model. This research not only contributes to the field of industrial machine learning by providing a nuanced approach to loss function customization but also underscores the importance of context-specific adaptations in machine learning algorithms. The results showcase the potential of tailored loss functions in balancing precision and efficiency, ensuring reliable and effective machine learning solutions in industrial settings.

4.
Polymers (Basel) ; 15(4)2023 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-36850342

RESUMO

The thermal treatment of wood can improve the appearance of the wood product's surface, its dimensional stability, and resistance to fungal attacks. However, the heat treatment changes the technological properties of wood, making it a new engineering material. This work investigates the effect of the low-thermal treatment of birch wood (Betula pendula Roth.), European beech wood (Fagus sylvatica L.), and alder wood (Alnus glutinosa L.) on the fine dust particles creation during woodworking. The samples of thermally treated wood with temperatures commonly used for the change of wood colour (105, 125, and 135 °C) were compared with reference samples made of natural wood. All 12 variants of the tested woods were milled using the 5-axis CNC machining center (20 mm diamond cutter, rotational speed 18,000 rev·min-1, the depth of cut 3 mm, feed rates of 2, 4 and 6 m∙min-1). A sieving analysis method allowed measuring the dust particle size distributions in all dust samples. The experiment's result analysis points out that wood type, thermal treatment, and feed rate meaningfully affect the size distribution of dust particles. Compared to birch wood and beech wood, the milling of alder wood samples created a much higher content of the finest dust particles, with particle sizes smaller than 0.032 mm. Increased temperatures in thermal treatment increase the share of fine dust particles with sizes smaller than 0.125 mm, compared to wood in its natural state. Milling with a lower feed rate (2 m·min-1) creates finer dust than processing with higher feed rates (4 and 6 m·min-1). Generally, the milling of alder in a natural or thermally treated state is a source of fine dust particles, particularly at low feed speed-rate milling, compared to birch and beech wood. In general, these results indicate that the low temperature thermal treatment parameters attribute new technological properties to all thermally modified types of wood tested.

5.
Environ Health Insights ; 16: 11786302221080829, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35237048

RESUMO

BACKGROUND: Occupational injuries are still a major public health problem and one of the leading causes of disability, morbidity, and mortality. This study aimed to assess occupational injuries and associated factors among workers in the small-scale woodworking industry in Hawassa city, southern Ethiopia. MATERIALS AND METHODS: An institutional-based cross-sectional study was conducted among 418 randomly selected small-scale woodworking industry workers. Questionnaires and an observational checklist were used to collect data. The data was entered into Epi data version 3.1 and analyzed using SPSS version 21. Multivariate logistic regression analysis with 95% CI and P < .05 was used to identify factors associated with occupational injury. RESULTS: The prevalence of at least one occupational injury in the previous 12 months among small-scale woodworking industry workers was 41.6% [95% CI: 36.9-46.4]. Work experience 1 to 2 years [AOR = 2.8, 95% CI: 1.49-5.2], working more than 48 hours per week [AOR = 2.2, 95% CI: 1.41-3.49], lack of occupational safety and health (OSH) training [AOR = 2.5, 95% CI: 1.35-4.75], and non-use of personal protective equipment (PPE) [AOR = 3.3, 95% CI: 1.85-5.83] were factors significantly associated with occupational injury. CONCLUSIONS: In this study, the prevalence of occupational injuries among workers in the small-scale woodworking industry was high. Lack of OSH training, non-use of PPE, work experience of 1 to 2 years, and working more than 48 hours per week were all factors that contributed to occupational injuries. Therefore, workers in the small-scale woodworking industry should receive ongoing occupational safety and health (OSH) training, and personal protective equipment (PPE) should be provided and monitored.

6.
Artigo em Inglês | MEDLINE | ID: mdl-35162168

RESUMO

BACKGROUND: Millions of workers around the world are exposed to wood dust, as a by-product of woodworking. Nasopharynx cancers (NPCs) and sinonasal cancers (SNCs) are two cancers that can be caused by occupational exposure to wood dust, but there is little evidence regarding their burden in Canada. OBJECTIVE: the aim of this study was to estimate the incidence and economic burden of newly diagnosed cases of NPC and SNC in 2011 in Canada, attributable to occupational exposures to wood dust. METHODS: calculating the incidence of cancer attributable to occupational exposure involved three steps of defining relative risk, assessing the prevalence of exposure and population modelling. We estimated the lifetime costs of newly diagnosed NPC and SNC from the societal perspective. The three major cost categories that we considered were direct costs (healthcare costs, out-of-pocket costs, and informal caregiving costs), indirect costs (labour productivity/output costs, employer adjustment costs, and home production losses), and intangible costs (health-related quality of life losses). To generate an estimate of economic burden, we used secondary data from multiple sources and applied them to our computational model developed from an extensive literature review. RESULTS: From approximately 1.3 million workers exposed to wood dust, we expected 28%, 43% and 29% were exposed to low, medium, and high levels, respectively. We estimated from 235 newly diagnosed cases of NPC and 245 newly diagnosed cases of SNC, 4.6% (11 cases) and 4.4% (11 cases) were attributed to occupational exposure to wood dust, respectively. Our estimates of the economic burden of occupational NPC and SNC were about CAD 5.4 million (CAD 496,311 per-case) and CAD 6.7 million (CAD 627,437 per-case), respectively. For NPC direct costs constituted approximately 20% of all costs, and indirect and intangible costs accounted for 55% and 25%, while for SNC the breakdown distribution were 16%, 42% and 42%, respectively. CONCLUSIONS: Our estimates highlighted the importance of occupational NPC and SNC amongst other occupational cancers, especially in countries with large wood-related industries. This paper also serves the information needs of policymakers who are seeking to make evidence-based decisions about occupational cancer prevention efforts.


Assuntos
Doenças Profissionais , Exposição Ocupacional , Neoplasias dos Seios Paranasais , Poeira , Humanos , Nasofaringe , Doenças Profissionais/epidemiologia , Exposição Ocupacional/análise , Qualidade de Vida , Madeira
7.
Materials (Basel) ; 14(16)2021 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-34443150

RESUMO

The article dealt with the assessment of the quality of hydraulic oil and determination of the mode of wear of the friction surfaces of Baljer & Zembrod manipulating lines through the information traces in the oils by applying tribotechnical diagnostics. We presented the assessment of the level of degradation of the oils. In addition, we presented the mode of wear of the friction surfaces washed in oil through evaluation of the qualitative and quantitative characteristics of the particles found in the oil. In detail, we focused on the application of suitable multivariate statistical methods on the data matrix. The article also presents predictive models that can sort oils into groups based on the assessment of quality of the oil and the state of the friction couples. The models can be used in research and in solving practical tasks in tribotechnical diagnostics of hydraulic fluids in woodworking equipment. Our results showed that the manipulation lines were greatly thermically stressed due to inadequate oil and machine maintenance. By correlative integration of all methods used, we could determine the real mode of the wear of the tribologic nodes of the machine. The experiment enabled the early detection of an undesirable process in the tribological node and implementation of corrective measures before the machine would break down.

8.
J Hum Evol ; 156: 102999, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34022498

RESUMO

Understanding early stone tools, particularly relationships between form and function, is fundamental to understanding the behavioral evolution of early hominins. The oldest-claimed flake tools date to ca. 3.3 million years ago, and their development may represent a key step in hominin evolution. Flake form, and its relationship to function, has long been a focus of Paleolithic studies, almost exclusively with respect to meat acquisition. However, evidence for woodworking is now known from sites dating to 1.5 Ma. Additionally, Pan troglodytes are known to manufacture wooden tools for hunting and foraging, thus creating a phylogenetic (parsimony) argument for more ancient woodworking. However, few studies examining woodworking and Paleolithic tools have been completed to date. Indeed, it remains an open question whether woodworking may have instigated specific selective demands on the form of early stone tools. Here, we conducted an experiment testing the comparative woodworking efficiency (measured by time) of small and large flakes. Two groups of participants used either a relatively small or large unretouched flake to remove a predefined area from standardized samples of wood. Those using larger flakes were significantly more efficient (i.e., required less time) during this woodworking task. Our results demonstrate that larger flakes could have been preferentially chosen by hominins for woodworking, consistent with previous data generated experimentally in other (non-woodworking) tasks. Moreover, the production of relatively large flakes, such as those at Lomekwi, could have been motivated by woodworking, rather than, or in addition to, butchery. Such issues may also have encouraged the use of Levallois production strategies in later times.


Assuntos
Arqueologia , Hominidae , Comportamento de Utilização de Ferramentas , Madeira , Animais , Feminino , Humanos , Masculino , Filogenia
9.
J Hand Surg Asian Pac Vol ; 26(1): 36-40, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33559580

RESUMO

Background: Angle grinders are a handheld power tool used for grinding and polishing stone, metal, and concrete. Some people, however, use them with a circular saw blade attachment for cutting wood and consequently, suffer injuries. We aimed to investigate the underlying cause and mechanisms of injuries caused by cutting wood with an angle grinder. Methods: We conducted a retrospective study using medical records from our trauma center and identified 15 patients treated for angle grinder injury between 2017 and 2018. Moreover, we contacted the National Consumer Affairs Center of Japan for further information about angle grinder injuries. Results: Nine of the 15 patients used angle grinders improperly, of which only three patients were aware of the risk of injury. The details of the nine patients were as follows: the types of injuries: complete finger amputation (n = 2), partial finger amputation (n = 1), tendon injury with phalangeal fracture (n = 5), and tendon injury alone, (n = 1); the causes of accidents: kickback (n = 7) and glove entanglement (n = 2); and the accident situations: on-the-job (n = 5) and do-it-yourself (n = 4). Conclusions: The primary cause of angle grinder injury caused by cutting wood was a lack of user knowledge that an angle grinder cannot be used as a cutting tool. Appropriate feedback from hand surgeons are necessary to urge manufacturers to take safety measures.


Assuntos
Amputação Traumática/etiologia , Traumatismos dos Dedos/etiologia , Falanges dos Dedos da Mão/lesões , Fraturas Ósseas/etiologia , Traumatismos dos Tendões/etiologia , Acidentes/estatística & dados numéricos , Adulto , Idoso , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Centros de Traumatologia , Madeira , Adulto Jovem
10.
J Med Life ; 13(2): 225-228, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32742518

RESUMO

The high prevalence of periodontal diseases in workers with professional contact with unfavorable factors of the production environment is an unresolved problem of dentistry. This study aimed to investigate the harmful effects of formaldehyde on periodontal tissues in woodworkers who have long-term contact with formaldehyde in their professional activities. Sixty-nine men with occupational exposure to formaldehyde were examined to study the effect of formaldehyde on the human periodontal tissues, looking particularly at signs of the periodontal tissues' inflammatory process using a series of periodontal indices. The study results showed that the condition of periodontal tissues was statistically significantly worse in woodworkers who have long-term contact with formaldehyde in their professional activities. However, the hygiene status was not significantly different in the main group and the comparison group. Thus, we concluded that working under conditions of constant exposure to formaldehyde has a negative effect on the condition of periodontal tissues.


Assuntos
Formaldeído/efeitos adversos , Indústrias , Exposição Ocupacional/análise , Periodonto/efeitos dos fármacos , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Saúde Bucal , Prevalência , Adulto Jovem
11.
Materials (Basel) ; 13(10)2020 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-32455996

RESUMO

The condition of the cutting tool is one of the most important factors as it directly affects the technological and economic efficiencies of the woodworking process. The large variety of raw materials of wood combined with possible impurities and inclusion of solids puts high demands on planing machines. One of the methods to modify their operational properties is to apply antiwear coating on their working surfaces using vacuum deposition methods, such as physical vapor deposition (PVD). The use of such coatings reduces the adhesion of planing products to the surface of industrial planer knives, reduces the friction between the cutting tool and the workpiece, and limits the penetration of heat into the tool, thereby contributing to extending its effective working life. This study examines the impact of PVD-based CrCN/CrN coating on the operational durability and intensity of wear of planer knives operating in production conditions compared to unmodified knives (typically used in the wood processing industry for pine wood planing). For the unmodified and CrCN/CrN-coated planing blades (before and after processing), detailed analyses were carried out. These analyses included determining the rounding radius and profile along the blade (worn edge displacement), calculating surface texture parameters of the rake face of planer knives, and carrying out visual microscopic analysis of its condition. The results of the experiments indicated an increase in durability of up to 142% for the CrCN/CrN-coated tools. It was also found that the use of PVD-based modified industrial planer knives turned out to be more beneficial in each analyzed area of analysis.

12.
Arh Hig Rada Toksikol ; 68(2): 127-134, 2017 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-28665796

RESUMO

Wood compounds, especially sterols, are connected with the level of contamination with microscopic fungi. Within this study, tests were conducted on wood dust samples collected at various work stations in a pine and birch timber conversion plant. Their contamination with mycobiota was measured as the concentration of ergosterol (ERG) by ultra performance liquid chromatography (UPLC). Another aim of this study was to assess the effect of contamination with microscopic fungi on the sterol contents in wood dusts. Analyses were conducted on five sterols: desmosterol, cholesterol, lanosterol, stigmasterol, and ß-sitosterol using UPLC and their presence was confirmed using gas chromatography/mass spectrometry (GC/MS). The results of chemical analyses showed the greatest contamination with mycobiota in birch wood dust. We also observed varied contents of individual sterols depending on the wood dust type. Their highest concentration was detected in birch dust. The discriminant analysis covering all tested compounds as predictors showed complete separation of all tested wood dust types. The greatest discriminatory power was found for stigmasterol, desmosterol, and ergosterol.


Assuntos
Betula/química , Poeira/análise , Fungos/química , Pinus/química , Esteróis/análise , Madeira/química , Madeira/microbiologia , Monitoramento Ambiental/métodos , Exposição Ocupacional/análise , Polônia
13.
Chir Main ; 33(5): 325-9, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25043313

RESUMO

The primary objective of this study was to describe the injury characteristics and demographics of patients injured during woodworking activities, upon their arrival to the emergency department in a regional of France where this industry is prevalent. The secondary objective was to compare patient and injury characteristics for work-related and hobby-related accidents. A cohort of 87 patients who had suffered a woodworking accident over a two-year period was evaluated; 79 were available for follow-up. The context and circumstances of the accident, nature and location of the injuries and patient demographics were recorded. Hobby-related accidents accounted for two-thirds of the accidents (51/79). Most of the injured workers were either loggers (35%) or carpenters (46%). The hand was injured in 53 cases (67%). Work-related accidents resulted in significantly more serious consequences in terms of hospital stay, work stoppage, resumption of work or retraining than hobby-related accidents. For the workplace accidents, 86% occurred on new machines; more than 25% of the machines involved in accidents at home were over 15 years. Sixty-eight per cent of workers were wearing their safety gear, while only 31% of those injured during recreational woodworking wore the appropriate gear. Several elements of prevention should be improved: information about the need to maintain the equipment, protect the worker with suitable clothing, and learn which maneuvers are considered hazardous. Safety gear should be regularly inspected in the workplace.


Assuntos
Acidentes de Trabalho/estatística & dados numéricos , Traumatismos da Mão/epidemiologia , Passatempos , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Amputação Traumática/epidemiologia , Estudos de Coortes , Indústria da Construção , Seguimentos , França/epidemiologia , Humanos , Tempo de Internação/estatística & dados numéricos , Pessoa de Meia-Idade , Equipamentos de Proteção/estatística & dados numéricos , Retorno ao Trabalho , Licença Médica/estatística & dados numéricos , Adulto Jovem
14.
Dendrochronologia (Verona) ; 32(1): 90-96, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-27667920

RESUMO

In the present study, 208 furniture and 168 coopered vessels from three Austrian museums were examined. Dendrochronology was used to date objects and to extract further information such as the necessary time for seasoning, wood loss through wood-working and methods of construction. In most cases sampling was done by sanding the cross section and making digital photographs using a picture frame and measuring digitally. The dendrochronological dates of the sampled furniture range between 1524 and 1937. The group of furniture includes cupboards, chests, tables, benches, commodes and beds. In many cases furniture was artfully painted and sometimes even shows a painted year. With the help of dendrochronology it was proved that some objects had been painted for some time after construction, or had been over-painted. Most furniture, however, was painted immediately after completion. In this case, the seasoning and storage time of the boards and the wood loss due to shaping can be verified. As an average value, 14 years have passed between the dendrochronological date of the outermost ring and the painting. The time span includes time of seasoning and storage and the rings lost by wood-working. This leads, on the one hand to a short storage time of less than 10 years and on the other hand to very little wood loss due to manufacturing. Those boards being less shaped turned out to be back panels of cupboards, therefore they are recommended to be sampled for dating. Coopered vessels were dated between 1612 and 1940. There was evidence that staves were split and not sawn in many cases. The staves were often split out of the outermost part of the tree and hardly any wood was worked away which was proved by the close dendrochronological dates of the single staves of a vessel. Since there is a short time of storage and only little wood loss through wood-working, dating of objects without a waney edge becomes reasonable.

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