A lithium-isotope perspective on the evolution of carbon and silicon cycles.

The evolution of the global carbon and silicon cycles is thought to have contributed to the long-term stability of Earth's climate1-3. Many questions remain, however, regarding the feedback mechanisms at play, and there are limited quantitative constraints on the sources and sinks of these elements in Earth's surface environments4-12. Here we argue that the lithium-isotope record can be used to track the processes controlling the long-term carbon and silicon cycles. By analysing more than 600 shallow-water marine carbonate samples from more than 100 stratigraphic units, we construct a new carbonate-based lithium-isotope record spanning the past 3 billion years. The data suggest an increase in the carbonate lithium-isotope values over time, which we propose was driven by long-term changes in the lithium-isotopic conditions of sea water, rather than by changes in the sedimentary alterations of older samples. Using a mass-balance modelling approach, we propose that the observed trend in lithium-isotope values reflects a transition from Precambrian carbon and silicon cycles to those characteristic of the modern. We speculate that this transition was linked to a gradual shift to a biologically controlled marine silicon cycle and the evolutionary radiation of land plants13,14.

Kinetic and Thermodynamic Interplay of Polymer-Mediated Liquid-Liquid Phase Separation for Poorly Water-Soluble Drugs.

Understanding the interplay between kinetics and thermodynamics of polymer-mediated liquid-liquid phase separation is crucial for designing and implementing an amorphous solid dispersion formulation strategy for poorly water-soluble drugs. This work investigates the phase behaviors of a poorly water-soluble model drug, celecoxib (CXB), in a supersaturated aqueous solution with and without polymeric additives (PVP, PVPVA, HPMCAS, and HPMCP). Drug-polymer-water ternary phase diagrams were also constructed to estimate the thermodynamic behaviors of the mixtures at room temperature. The liquid-liquid phase separation onset point for CXB was detected using an inline UV/vis spectrometer equipped with a fiber optic probe. Varying CXB concentrations were achieved using an accurate syringe pump throughout this study. The appearance of the transient nanodroplets was verified by cryo-EM and total internal reflection fluoresence microscopic techniques. The impacts of various factors, such as polymer composition, drug stock solution pumping rates, and the types of drug-polymer interactions, are tested against the onset points of the CXB liquid-liquid phase separation (LLPS). It was found that the types of drug-polymer interactions, i.e., hydrogen bonding and hydrophobic interactions, are vital to the position and shapes of LLPS in the supersaturation drug solution. A relation between the behaviors of LLPS and its location in the CXB-polymer-water ternary phase diagram was drawn from the findings.

The historical sociology of medicine in India: Introduction to the special section.

This introduction to a special section brings together three papers first presented at a panel, 'Medical Professions in South Asia: Historical and Contemporary Analyses', at the 26th European Conference on South Asian Studies, held in Vienna, Austria and online, in July 2021. All three papers deal with aspects of the professionalisation of biomedical doctors in India since its independence in 1947. The authors bring together historical and sociological approaches to illuminate the growth of specialisms, patterns of practitioner-patient interactions and efforts to maintain occupational closure and maintain status in the face of growing challenges. The introduction concludes with a discussion of the relevance of these papers for the sociology of health and illness in India and beyond.

An Ethical Framework for Research Using Genetic Ancestry.

A wide range of research uses patterns of genetic variation to infer genetic similarity between individuals, typically referred to as genetic ancestry. This research includes inference of human demographic history, understanding the genetic architecture of traits, and predicting disease risk. Researchers are not just structuring an intellectual inquiry when using genetic ancestry, they are also creating analytical frameworks with broader societal ramifications. This essay presents an ethics framework in the spirit of virtue ethics for these researchers: rather than focus on rule following, the framework is designed to build researchers' capacities to react to the ethical dimensions of their work. The authors identify one overarching principle of intellectual freedom and responsibility, noting that freedom in all its guises comes with responsibility, and they identify and define four principles that collectively uphold researchers' intellectual responsibility: truthfulness, justice and fairness, anti-racism, and public beneficence. Researchers should bring their practices into alignment with these principles, and to aid this, the authors name three common ways research practices infringe these principles, suggest a step-by-step process for aligning research choices with the principles, provide rules of thumb for achieving alignment, and give a worked case. The essay concludes by identifying support needed by researchers to act in accord with the proposed framework.

Changes of heart: Debating the role of cardiology and cardiac surgery in India, 1948-1968.

In 1950, the leaders of independent India celebrated the contributions that surgeons could make to modernising India. Surgeons, however, faced a difficult choice. Some wanted to invest in generalist surgeons to make basic surgical care available to all Indians. Others wanted to invest in specialists to ensure that India participated in cutting-edge surgical research and care. These debates shaped the emergence of cardiac surgery at two centres: the Christian Medical College in Vellore and the King Edward Memorial Hospital in Bombay. CMC invested in thoracic surgery in the 1940s to offer new treatments for tuberculosis. This gave surgeons the opportunity to explore new techniques of cardiac surgery. Debate quickly emerged about whether investments in cardiology and cardiac surgery made sense. In the end, the specialities were supported in order to attract paying patients. A parallel controversy took place at KEM, where the dean debated the Bombay Municipal Corporation about the role of surgical research at a public hospital. The Rockefeller Foundation influenced both sites, offering financial support if they adopted an American model of full-time faculty clinician-researchers. The two case studies reveal how unusual dynamics could contribute to the establishment of new medical specialities in India.

Unpacking the '15-Minute City' via 6G, IoT, and Digital Twins: Towards a New Narrative for Increasing Urban Efficiency, Resilience, and Sustainability.

The '15-minute city' concept is emerging as a potent urban regeneration model in post-pandemic cities, offering new vantage points on liveability and urban health. While the concept is primarily geared towards rethinking urban morphologies, it can be furthered via the adoption of Smart Cities network technologies to provide tailored pathways to respond to contextualised challenges through the advent of data mining and processing to better inform urban decision-making processes. We argue that the '15-minute city' concept can value-add from Smart City network technologies in particular through Digital Twins, Internet of Things (IoT), and 6G. The data gathered by these technologies, and processed via Machine Learning techniques, can unveil new patterns to understand the characteristics of urban fabrics. Collectively, those dimensions, unpacked to support the '15-minute city' concept, can provide new opportunities to redefine agendas to better respond to economic and societal needs as well as align more closely with environmental commitments, including the United Nations' Sustainable Development Goal 11 and the New Urban Agenda. This perspective paper presents new sets of opportunities for cities arguing that these new connectivities should be explored now so that appropriate protocols can be devised and so that urban agendas can be recalibrated to prepare for upcoming technology advances, opening new pathways for urban regeneration and resilience crafting.

Innovation and Tribulation in the History of Randomized Controlled Trials in Surgery.

Despite persistent critiques of the rigor of surgical research, surgeons have actually pursued careful empirical studies for centuries. Their work has enriched not only surgical science but also the development of evidencebased medicine. From conducting landmark controlled trials, to using statistics, alternate patient allocation, randomization, and sham controls, surgeons have long embraced innovative trial approaches and played important roles in the development of key methods of RCTs. However, historical contexts unique to surgery have shaped the implementation of RCTs in this field. Unlike the history of pharmaceuticals, in which substantial research funding has been devoted to testing new drugs before their approval, surgical trials have followed a different trajectory. New operations have repeatedly come into wide use in the absence of RCTs. On many occasions, when established procedures have become controversial, surgeons have then marshaled the resources to conduct RCTs reassessing the operations. Such trials have triggered powerful debates in which proponents of surgical RCTs battled against ingrained practices and preferences. In such cases, RCTs often were not decisive factors in determining the fate of surgical practices but supporting tools that followed and reflected changes in surgical judgment already underway. Surgical trialists also have encountered specific, recurring challenges, especially with the methodological and ethical complexity of blinded and sham-controlled trials. The history of surgical trials thus reveals major contributions from surgeons to the advancement of evidence-based medicine, as well as ongoing challenges. Strengthened and systematic trial support could advance the future of surgical RCTs.

Pandemic stricken cities on lockdown. Where are our planning and design professionals [now, then and into the future]?

Chinese cities have been placed upon lockdown in early 2020 in an attempt to contain the novel coronavirus (COVID-19), as increasingly huge demands are being placed upon Chinese and international health professionals to address this pandemic. Surprisingly, planning and design professionals are absent in the discourses about existing and post-COVID-19 strategies and actions even though previous pandemics historically revealed major impacts on the urban fabric from social and economic perspectives. This paper is a call for action for international architectural and urban organisations to include pandemics and similar in their disaster management strategies. This need is very evident in their need to better design creative and relevant protocols in partnership with health discipine organisations, and so that their applied deployment in pandemic stricken cities can be effected integrated seamlessly within normal city environment planning activities and also in incident situations like containing the current COVID-19 pandemic.