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Cutting tool materials are the backbone of machining and play a vital role in the manufacturing industry. Innovation in cutting tools is important for customized and demanding applications. This state-of-the-art review is focused on innovations and future research directions for cutting tools covering i) tool materials/microstructure/property relationships, ii) coatings and their effect on tool performance, iii) cutting edge and functional surface preparation and effect on tool performance, iv) tool geometry for high performance and stable machining considering rapid machining, sustainability, and circularity aspects. The vision is to identify tool material/coating/geometry/functional surface relationships for significant improvement in machining performance. This paper includes perspectives from several research groups with a detailed discussion on current advances, capabilities, and challenges in engineered design of cutting tools, materials, coatings, structures and sets a new agenda for future tooling and research directions. [ABSTRACT FROM AUTHOR]

Today more than ever, educational institutions need educational leaders who are able to promote profound, substantive and sustainable change. This paper is based on the efforts and results of the first stage of a European project implemented in universities and primary and secondary schools in Spain, Finland and the Czech Republic. The project seeks to explore the changes (and its educational effects) that have occurred in the last decade regarding digital competencies, especially in relation to the emergence of a culture of collaboration that connects youth learning, technology and a Do-it-Yourself (DIY) ethos. To achieve the project's objective, we followed a methodology based on the principles of collaborative action research (CAR). We have analysed the curricula and study plans of the participating institutions in order to explore how and where the project could be applied. We conducted a series of focus groups with teachers, students and parents to discuss notions of DIY learning among the educational communities. Based on these discussions, we began to analyse how each context envisions DIY learning and how it relates to the notion of virtual space. We finished the first stage with the professional development of the teachers, which was aimed at shaping the DIYLabs implementation plan.

This article focuses on the relevance that aesthetic practices play extending parental involvement and influence in school contexts in Spain. One rural, one urban and one peri-urban school have been included in the research. Participant observation and interviews were the main means of data production. In the results all the different schools promoted parents' participation. However, differences in aesthetic practices and experiences were found. Parental involvement was developed in schools in different ways in relation to local contextual conditions and the salient characteristics of the geographic spaces the schools belonged to. Practical aesthetic knowledge produced multiple strategies of action.

Abstract Transketolase (TK) has been previously engineered, using semi-rational directed evolution and substrate walking, to accept increasingly aliphatic, cyclic, and then aromatic substrates. This has ultimately led to the poor water solubility of new substrates, as a potential bottleneck to further exploitation of this enzyme in biocatalysis. Here we used a range of biophysical studies to characterise the response of both E. coli apo- and holo-TK activity and structure to a range of polar organic co-solvents: acetonitrile (AcCN), n-butanol (nBuOH), ethyl acetate (EtOAc), isopropanol (iPrOH), and tetrahydrofuran (THF). The mechanism of enzyme deactivation was found to be predominantly via solvent-induced local unfolding. Holo-TK is thermodynamically more stable than apo-TK and yet for four of the five co-solvents it retained less activity than apo-TK after exposure to organic solvents, indicating that solvent tolerance was not simply correlated to global conformational stability. The co-solvent concentrations required for complete enzyme inactivation was inversely proportional to co-solvent log(P), while the unfolding rate was directly proportional, indicating that the solvents interact with and partially unfold the enzyme through hydrophobic contacts. Small amounts of aggregate formed in some cases, but this was not sufficient to explain the enzyme inactivation. TK was found to be tolerant to 15% (v/v) iPrOH, 10% (v/v) AcCN, or 6% (v/v) nBuOH over 3 h. This work indicates that future attempts to engineer the enzyme to better tolerate co-solvents should focus on increasing the stability of the protein to local unfolding, particularly in and around the cofactor-binding loops.

Inconel 718 is a widely used alloy in the aeronautic sector due to its excellent mechanical and corrosion wear resistance under high temperature conditions. However, its good mechanical properties can be a double edge sword in terms of manufacturing, especially in those processes based in mechanical principles, such as machining or forming. Considering that most aeronautic components are exposed to cyclic load and temperature, fatigue resistance becomes critical, and therefore, the finishing processes. The surface integrity of a component plays an important role on its fatigue behaviour, as the most common crack initiation area is usually the surface. The present work compares three different mechanical finishing processes that confer better surface properties to the component: polishing, burnishing, and hammer-peening. Each one achieves different degrees of roughness, and residual stress on the surface. The study is not only focused on the resultant mechanical properties, but also in productivity and process robustness. It is concluded that each technology excels in a different property.

Abstract Replacement of pollutant fluids with eco-friendly strategies in machining operations significantly contributes to protecting the environment, diminishing global warming, and ensuring a healthier workplace for employees. This study compares cryogenic coolants with conventional coolants in cylindrical plunge grinding using a Cubic Boron Nitride (CBN) wheel. Samples of 27MnCr5 steel used in the manufacture of automotive transmission components were ground using (i) Liquid Nitrogen (LN2), (ii) a combination of LN2 + Minimum Quantity Lubrication (MQL), and (iii) a conventional coolant. The effects of the different cooling methods on the surface integrity of the ground surfaces were examined in terms of surface roughness, microstructural defects, microhardness profiles, and residual stresses. In general, surface roughness was similar for the tested cooling systems, even after grinding three subsequent surfaces in which the process stability was analyzed. Interestingly, the use of eco-friendly cryogenic systems induced fewer microstructural defects than conventional systems, and particularly, LN2+MQL lead to more compressive surface residual stresses that would improve the in-service performance of components. These results show opportunities for replacing conventional pollutant systems with eco-friendly cryogenic strategies for refrigerating/lubricating grinding processes to reduce harmful effects on the environment and pose health risks to operators.

Prostate cancer (PCa) is the second most frequent cancer diagnosed in men worldwide. The detection methods for PCa are either unreliable, like prostate-specific antigen (PSA), or extremely invasive, such as in the case of biopsies. Therefore, there is an urgent necessity for reliable and less invasive detection procedures that can differentiate between patients with benign diseases and those with cancer. In this matter, microRNAs (miRNAs) are suggested as potential biomarkers for cancer. MiRNAs have been found to be dysregulated in several different cancers, and these genetic alterations may present specific signatures for a given malignancy. Here, we examined the expression of miR141-3p, miR145-5p, miR146a-5p, and miR148b-3p in human tissue samples of PCa ( n = 41) and benign prostatic diseases (BPD) ( n = 30) using reverse transcription-quantitative polymerase chain reaction (RT-qPCR). We combined the expression results with patient clinicopathological characteristics in logistic regression models to create accurate PCa predictive models. A model including information of miR148b-3p and patient age showed relevant prediction results (area under the curve [AUC] = 0.818, precision = 0.763, specificity = 0.762, and accuracy = 0.762). A model including all four miRNAs and patient age presented outstanding prediction results (AUC = 0.918, precision = 0.861, specificity = 0.861, and accuracy = 0.857). Our results represent a potential novel procedure based on logistic regression models that utilize miRNA expressions and patient age to assist with PCa diagnosis.

ABSTRACT: Current commercial strains of broiler breeders display reproductive dysregulation when fed to satiety, but they can achieve optimal hatching egg production under feed restriction. However, chronic feed restriction in broiler breeders is a welfare concern due to physiological and behavioral signs of hunger, lack of satiety, and frustrated feeding motivation. The purpose of this study was to assess the welfare and productivity of slower-growing broiler breeders during lay. A total of 336 broiler breeders from 5 strains of slower-growing broiler breeders (3 female strains: 100 hens per strain, and 2 male strains: 12 and 24 roosters per strain) were kept in 12 identical pens throughout lay, 4 pens per combination of roosters and hens: A hens with Y roosters, B hens with Y roosters, and C hens with X roosters. According to guidelines, strain B and C hens and X roosters were slower growing strains and strain A hens and Y roosters were intermediate growing strains. Egg production was recorded daily, and settable eggs laid at 30, 40, and 50 wk of age were incubated to hatch. Growth rate, feed and water intake, and welfare indicators (feeding motivation, behavior, and physical assessment: feather coverage, foot and leg health, and keel bone status) were recorded during lay. Additionally, a subsample of 5 hens per pen was dissected for anatomical analyses. Laying rate started and peaked earlier in B hens than in A hens and remained above 70% in both strains, yielding high cumulative egg production (>165 eggs/hen) until 53 wk of age. Until 50 wk of age, fertility and hatched of fertile was high in slower growing broiler breeders, on average, above 95 and 80%, respectively. Compared to A hens, B and C hens had better feather coverage, lower feeding motivation, and lower daily water and feed intake. Results of this study suggest that slower growing broiler breeders show reduced signs of poor welfare and improved productivity during lay although susceptibility to obesity-related problems on laying rate may be strain-specific.

The purpose of this article is twofold: firstly, to highlight how school strategies and priorities relate to family participation practices through social media and, secondly, to further our knowledge of the basic aspects involved. The concept of cultural capital is used to discuss how parental resources affect virtual family participation and how these virtual family participation practices can unfold and enable families to participate in each school we researched. We observed how the schools seemed to prioritise virtual family participation practices based on information practices. The study also raises questions concerning a digital divide, in terms of the possibilities that virtual space offers to extend parental participation in schools and to extend the study of this participation.

Six-axis robots are increasingly employed in manufacturing due to their excellent volume on cost ratio and extensive reach, facilitating the machining of large components, including those made of composites. However, this enhanced volume on cost ratio often compromises rigidity. This study investigates the effect of cutting conditions on surface integrity and robotic drilling forces when machining Aluminum 6082-GFRP stacks using 6 mm solid carbide drills and a 6-axis Sta¨ubli TX200 robot. Two distinct drill geometries are assessed in various drilling sequences. Feed rate emerges as a pivotal parameter affecting drilling forces and hole quality. Comprehensive testing encompasses a range of feed rates and drilling strategies in both individual materials and stack sequences. The analysis includes cutting forces and hole quality, considering surface integrity and standard quality indicators such as delamination, arithmetic roughness, and burr height. The research seeks to propose optimal cutting conditions, specifically feed rate and cutting speed, essential for advanced industrial applications. These conditions ensure hole quality and surface integrity, which is particularly important for riveting processes and ensuring effective sealing. [ABSTRACT FROM AUTHOR]

Thin-walled aluminium components used in the structure of aircrafts are subjected to fatigue loads. Fatigue performance of those components is affected by the surface integrity generated in the last machining step. This paper proposes an analytical model to identify the fatigue crack initiation site considering the surface topography, residual stresses (RS) and mechanical properties induced by machining. To validate the model fatigue samples of aluminium 7050-T7451 were prepared by face milling. Machining-induced RS were measured by hole-drilling and the surface topography of the gauge region of the fatigue samples was characterised using a confocal microscope. Then, uniaxial fatigue tests were done at R = 0.1 and subsequently the fracture was analysed. The model predicted nucleation of cracks at the surface when the stress amplitude was above 290 MPa. Fatigue tests done at an amplitude of 350 MPa confirmed crack initiation at the points with the highest stress concentration predicted by the model. By contrast, the cracks were nucleated at the side of the samples when the stress amplitude was below 290 MPa. In fact, compressive RS induced by face milling protected the surface from crack nucleation at lower applied stresses as predicted by the model. [ABSTRACT FROM AUTHOR]

Titanium alloy Ti6Al4V is of great importance to the aeronautical and medical sectors due to its mechanical properties such as a high strength-to-weight ratio and corrosion resistance. On the downside, machining Ti6Al4V can lead to accelerated tool wear and poor surface finish of the machined part due to its low heat dissipation capacity. Traditionally, oil and water based metalworking fluids (MWFs) have been used to overcome such issues. However, new regulations and eco-friendly manufacturing trends suggest that conventional MWFs should be minimised, as they are hazardous to the environment and workers' health. Additionally, titanium prostheses contaminated with oil can cause severe integration problems on the patient. This article researches the feasibility of replacing conventional emulsions with sustainable liquid carbon dioxide (LCO 2) cooling. For this purpose, an optimisation of the tool geometry (helix angle, clearance angle and cutting edge geometry) for LCO 2 assisted milling of Ti6Al4V was carried out, taking into account parameters such as cutting forces, surface roughness and the microstructure of the machined surface. This research contributes to the development of environmentally friendly and work safe manufacturing processes that meet the challenges of machining Ti6Al4V for aerospace and medical applications. [ABSTRACT FROM AUTHOR]

Abstract High-precision metal cutting is increasingly relevant in advanced applications. Such precision normally requires a cutting feed in the micron or even sub-micron dimension scale, which raises questions about applicability of concepts developed in industrial scale machining. To address this challenge, we have developed a device to perform linear cutting with force measurement in the vacuum chamber of an electron microscope, which has been utilised to study the cutting process down to 200 nm of the feed and the tool tip radius. The machining experiments carried out in-operando in SEM have shown that the main classical deformation zones of metal cutting: primary, secondary and tertiary shear zones—were preserved even at sub-micron feeds. In-operando observations and subsequent structural analysis in FIB/SEM revealed a number of microstructural peculiarities, such as: a substantial increase of the cutting force related to the development of the primary shear zone; dependence of the ternary shear zone thickness on the underlaying grain crystal orientation. Measurement of the cutting forces at deep submicron feeds and cutting tool apex radii has been exploited to discriminate different sources for the size effect on the cutting energy (dependence of the energy on the feed and tool radius). It was observed that typical industrial values of feed and tool radius imposes a size effect determined primarily by geometrical factors, while in a sub-micrometre feed range the contribution of the strain hardening in the primary share zone becomes relevant.

Resumen: Objetivo: Conocer las percepciones y actitudes de profesionales médicos de familia (MF) ante consultas con gran componente emocional, denominadas inicialmente «consultas sagradas», e identificar ámbitos de mejora en su atención. Diseño: Metodología cualitativa con enfoque sociosubjetivo orientado a los servicios de salud. Estudio descriptivo-interpretativo. Emplazamiento: Centros de salud de Araba y Bizkaia. Participantes y/o contextos: Selección de 23 MF de 23 centros de salud urbanos y rurales. Método: Muestreo intencional buscando la diversidad discursiva. Datos generados en 2016 mediante 3 grupos de discusión y 3 entrevistas individuales grabadas y transcritas tras consentimiento informado. Presentación al Comité de Ética de Euskadi. Análisis temático con ayuda de mapas conceptuales y programa MaxQDA. Triangulación de los resultados entre investigadores y verificación por los participantes. Resultados y discusión: Los hallazgos se agruparon en áreas temáticas solapadas entre sí y relacionadas con el significado de dichas consultas, actitudes profesionales, contexto sanitario y pacientes. Se subraya la importancia de lo emocional en las consultas de atención primaria y su invisibilización, pero se cuestiona la idoneidad del término «sagradas». Su expresión se construye en la interrelación MF-paciente si el personal médico lo favorece y el paciente lo permite, discutiéndose las principales circunstancias que intervienen en una dimensión considerada clave de la integralidad de la atención. Conclusiones: La atención a la dimensión emocional en la consulta presenta deficiencias que es necesario subsanar. Además de su reconocimiento y evaluación, sería preciso modificar los factores organizativos, formativos y profesionales que condicionan la implicación del personal MF en su buena asistencia. Abstract: Objective: To determine the perceptions and attitudes of the general practitioners (GP) towards consultations with great emotional component, initially called “sacred encounters”, and to identify areas of improvement. Design: A qualitative methodology based on a socio-subjective approach and focused on health services research. Descriptive-interpretative study. Location: Health Centres of Alava and Biscay. Participants: Selection of 23 GP from 23 urban and rural Health Centres. Method: Intentional sampling aimed at looking for discursive diversity. Data generated in 2016 by means of 3 discussion groups and 3 individual interviews recorded and transcribed after informed consent. Presentation to the ethics committee of the Basque Country. Thematic analysis with the aid of conceptual maps and MaxQDA program. Triangulation of the results between researchers and verification by the participants. Results and discussion: The findings were clustered into overlapping thematic areas related to the meaning of these encounters, attitudes of GP, health context, and patients. The importance of the emotions in primary care encounters and their invisibility is underlined, but the adequacy of the term “sacred” is questioned. This expression is built into the GP-patient relationship, if GP favours it and the patient also allows it, discussing the main circumstances that intervene in an essential dimension of integral care. Conclusions: The attention to the emotional dimension in the encounters has deficiencies that need to be corrected. In addition to its recognition and evaluation, it would be necessary to modify the organisational, training and professional factors that determine the involvement of the GPs in their good health care.

This work provides three new photographic records and evidence of increase in distribution of Heloderma alvarezi based on different encounters between human activities and the displacement of this species along the central coast of Oaxaca, Mexico. Until now, this species occurred only in Chiapas State, however, the new records provide information about the increase in species distribution on the coast of Oaxaca, so this has increased the number of reptiles in Oaxaca to 448 species.

Marijuana (Cannabis sp.) is among the most recurred controlled substances in the world, and there is a growing tendency to legalize its possession and use; however, the genotoxic effects of marijuana remain under debate. A clear definition of marijuana's genotoxic effects remains obscure by the simultaneous consumption of tobacco and other recreational substances. In order to assess the genotoxic effects of marijuana and to prevent the bias caused by the use of substances other than cannabis, we recruited marijuana users that were sub-divided into three categories: (1) users of marijuana-only (M), (2) users of marijuana and tobacco (M+T), and (3) users of marijuana plus other recreative substances or illicit drugs (M+O), all the groups were compared against a non-user control group. We quantified DNA damage by detection of γH2AX levels and quantification of micronuclei (MN), one of the best-established methods for measuring chromosomal DNA damage. We found increased levels of γH2AX in peripheral blood lymphocytes from the M and M+T groups, and increased levels of MNs in cultures from M+T group. Our results suggest a DNA damage increment for M and M+T groups but the extent of chromosomal damage (revealed here by the presence of MNs and NBuds) might be related to the compounds found in tobacco. We also observed an elevated nuclear division index in all marijuana users in comparison to the control group suggesting a cytostatic dysregulation caused by cannabis use. Our study is the first in Mexico to assess the genotoxicity of marijuana in mono-users and in combination with other illicit drugs.

Purpose Youth are exposed to many types of protobacco influences, including smoking in movies, which has been shown to cause initiation. This study investigates associations between different channels of protobacco media and susceptibility to smoking cigar