Project description:Switchable tribological properties of ferroelectrics offer an alternative route to visualize and control ferroelectric domains. Here, we observe the switchable friction and wear behavior of ferroelectrics using a nanoscale scanning probe-down domains have lower friction coefficients and show slower wear rates than up domains and can be used as smart masks. This asymmetry is enabled by flexoelectrically coupled polarization in the up and down domains under a sufficiently high contact force. Moreover, we determine that this polarization-sensitive tribological asymmetry is widely applicable across various ferroelectrics with different chemical compositions and crystalline symmetry. Finally, using this switchable tribology and multi-pass patterning with a domain-based dynamic smart mask, we demonstrate three-dimensional nanostructuring exploiting the asymmetric wear rates of up and down domains, which can, furthermore, be scaled up to technologically relevant (mm-cm) size. These findings demonstrate that ferroelectrics are electrically tunable tribological materials at the nanoscale for versatile applications.
Project description:Journals have been described as "duty bearers" of upholding fundamental ethical principles that are essential for maintaining the ethical integrity of newly generated and disseminated knowledge. To play our part, we evaluated diversity and inclusion in the leadership and management of global and international health journals. We developed Journal Diversity Index (JDI) to measure three parameters of diversity and representation (gender, geographic, socioeconomic status). Relevant information regarding editorial board members of systematically screened journals was sequentially extracted and job titles were categorized into five editorial roles. Chi-squared test was utilized to study associations between gender and geographic distribution of editors along with the Medline indexing of the journal and its impact factor. Out of 43 journals included, 62.7% were published from two high-income countries. Women comprised 44% of the total editors. Among all the editorial board members, we did not find any information suggesting the representation of non-binary and transgender individuals. Furthermore, 68.2% of editors were based in high-income countries with 67.3% of the editors belonging to the Global North. This disparity in geographic region and socioeconomic level was observed across all five editorial roles. Among all women editors, more than 70% worked in non-Medline and non-impact factor journals. Only two journals scored "excellent" on JDI. Despite the continuous evolution of the definition of global health ethics, marginalized individuals, and their perspectives remain underrepresented in this field. Thus, we call for swift action regarding the decentralization and redistribution of global and international health journal editorial boards.Supplementary informationThe online version contains supplementary material available at 10.1007/s41649-023-00243-8.
Project description:Solutions for the generation of FAIR (Findable, Accessible, Interoperable, and Reusable) data and metadata in experimental tribology are currently lacking. Nonetheless, FAIR data production is a promising path for implementing scalable data science techniques in tribology, which can lead to a deeper understanding of the phenomena that govern friction and wear. Missing community-wide data standards, and the reliance on custom workflows and equipment are some of the main challenges when it comes to adopting FAIR data practices. This paper, first, outlines a sample framework for scalable generation of FAIR data, and second, delivers a showcase FAIR data package for a pin-on-disk tribological experiment. The resulting curated data, consisting of 2,008 key-value pairs and 1,696 logical axioms, is the result of (1) the close collaboration with developers of a virtual research environment, (2) crowd-sourced controlled vocabulary, (3) ontology building, and (4) numerous – seemingly – small-scale digital tools. Thereby, this paper demonstrates a collection of scalable non-intrusive techniques that extend the life, reliability, and reusability of experimental tribological data beyond typical publication practices.
Project description:BackgroundThe Breast Health Global Initiative (BHGI) established a series of resource-stratified, evidence-based guidelines to address breast cancer control in the context of available resources. Here, the authors describe methodologies and health system prerequisites to support the translation and implementation of these guidelines into practice.MethodsIn October 2018, the BHGI convened the Sixth Global Summit on Improving Breast Healthcare Through Resource-Stratified Phased Implementation. The purpose of the summit was to define a stepwise methodology (phased implementation) for guiding the translation of resource-appropriate breast cancer control guidelines into real-world practice. Three expert consensus panels developed stepwise, resource-appropriate recommendations for implementing these guidelines in low-income and middle-income countries as well as underserved communities in high-income countries. Each panel focused on 1 of 3 specific aspects of breast cancer care: 1) early detection, 2) treatment, and 3) health system strengthening.ResultsKey findings from the summit and subsequent article preparation included the identification of phased-implementation prerequisites that were explored during consensus debates. These core issues and concepts are key components for implementing breast health care that consider real-world resource constraints. Communication and engagement across all levels of care is vital to any effectively operating health care system, including effective communication with ministries of health and of finance, to demonstrate needs, outcomes, and cost benefits.ConclusionsUnderserved communities at all economic levels require effective strategies to deploy scarce resources to ensure access to timely, effective, and affordable health care. Systematically strategic approaches translating guidelines into practice are needed to build health system capacity to meet the current and anticipated global breast cancer burden.
Project description:Monkeypox is caused by an orthopoxvirus, which is a DNA virus. Monkeypox is a zoonotic viral infection that has been endemic in West Africa and Central Africa for over a decade. Between 1 January and 22 June 2022, the World Health Organization (WHO) reported 3,413 laboratory-confirmed cases of monkeypox from 50 countries. Most cases (86%) were reported from Europe, with 2% from Africa and 11% from North and South America. In the US, the Centers for Disease Control and Prevention (CDC) identified an outbreak of monkeypox on May 17, 2022. In 99% of cases, the patients were men, 94% reported male-to-male sexual contact or intimate contact in the three weeks before they experienced symptoms of infection, 46% reported one or more genital lesions, and 41% had HIV infection. This initial data from the US showed widespread community transmission of monkeypox that mainly affected bisexual, gay, other men who had sex with men, and also ethnic and racial minority groups. Therefore, public health efforts in the US aim to prioritize these specific demographic groups for infection prevention and testing. By August 4, 2022, the US Department of Health and Human Services declared the monkeypox outbreak a public health emergency. This Editorial aims to present the current status of non-endemic global infections with the monkeypox virus, and current strategies for its prevention and management.
Project description:The discipline of cardio-oncology has expanded at a remarkable pace. Recent developments and challenges to clinicians who practice cardio-oncology were presented at the Global Cardio-Oncology Summit on October 3 to 4, 2019, in São Paulo, Brazil. Here, we present the top 10 priorities for our field that were discussed at the meeting, and also detail a potential path forward to address these challenges. Defining robust predictors of cardiotoxicity, clarifying the role of cardioprotection, managing and preventing thromboembolism, improving hematopoietic stem cell transplant outcomes, personalizing cardiac interventions, building the cardio-oncology community, detecting and treating cardiovascular events associated with immunotherapy, understanding tyrosine kinase inhibitor cardiotoxicity, and enhancing survivorship care are all priorities for the field. The path forward requires a commitment to research, education, and excellence in clinical care to improve our patients' lives.
Project description:Surface roughness affects many properties of colloids, from depletion and capillary interactions to their dispersibility and use as emulsion stabilizers. It also impacts particle-particle frictional contacts, which have recently emerged as being responsible for the discontinuous shear thickening (DST) of dense suspensions. Tribological properties of these contacts have been rarely experimentally accessed, especially for nonspherical particles. Here, we systematically tackle the effect of nanoscale surface roughness by producing a library of all-silica, raspberry-like colloids and linking their rheology to their tribology. Rougher surfaces lead to a significant anticipation of DST onset, in terms of both shear rate and solid loading. Strikingly, they also eliminate continuous thickening. DST is here due to the interlocking of asperities, which we have identified as "stick-slip" frictional contacts by measuring the sliding of the same particles via lateral force microscopy (LFM). Direct measurements of particle-particle friction therefore highlight the value of an engineering-tribology approach to tuning the thickening of suspensions.
Project description:In this study, we investigated the rheological and tribological properties of biopolymer mixtures of gelatinized corn starches (0.5 - 10.0 wt%) and κ-carrageenan (κC) (0.05 - 1.0 wt%). Two different starch samples were used. The first starch (CS1), despite extensive heating and shearing contained "ghost" granules, while the second starch (CS2) had no visible ghost granules after the same gelatinization process as CS1. Apparent viscosity measurements demonstrated that κC + CS1 mixtures were shear thinning liquids, with viscosity values being lower than the corresponding weight average of the values of the individual equilibrium phases at shear rates < 50 s-1 . Tribological results revealed that κC ≥ 0.5 wt% was required to observe any decrease in friction coefficients in the mixed lubrication regime. Starch (CS1) showed an unusual behavior at ≥ 5 wt%, where the friction coefficient decreased not only in the mixed regime but also in the boundary regime, probably due to the presence of the "ghost" granules, as the latter became entrained in the contact region. The CS1 + κC mixtures showed significantly lower friction coefficients than that of pure CS1 and κC in the mixed regime. However, the CS2 + κC mixture (i.e., containing no ghost granules) showed similar behavior to pure κC in the mixed regime, while lower friction coefficients than that of the pure CS2 and κC in the boundary regime. These findings illustrate new opportunities for designing biopolymer mixtures with tunable lubrication performance, via optimizing the concentrations of the individual biopolymers and the gelatinization state of the starch.