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This paper re-evaluates the formative year of quantum mechanics—from Heisenberg's first paper on matrix mechanics to Schrödinger's equivalence proof—by focusing on the role of radiation in the emerging theory. We argue that the radiation problem played a key role in early quantum mechanics, a role that has not been taken into account in the standard histories. Radiation was perceived by the main protagonists of matrix and wave mechanics as a central lacuna in these emerging theories and continued to contribute to the theoretical development and conceptual clarification of quantum mechanics. Studying the interplay between quantum mechanics and radiation, the paper provides an account of (a) how quantum mechanics was able to connect to its empirical basis in spectroscopy and (b) how Schrödinger's equivalence proof emerged from his explorative calculations on the emission of radiation. [ABSTRACT FROM AUTHOR]

This paper studies the notion of virtuality in the Bohr-Kramers-Slater theory of 1924. We situate the virtual entities of BKS within the tradition of the correspondence principle and the radiation theory of the Bohr model. We show how, in this context, virtual oscillators emerged as classical substitute radiators and were used to describe the otherwise elusive quantum transitions. They played an effective role in the quantum theory of radiation while remaining categorically distinct and ontologically separated from the quantum world of the Bohr model. The notion of virtuality thus differs markedly from its counterpart in quantum mechanics or QFT. [ABSTRACT FROM AUTHOR]

The European Physical Journal H (EPJH) is undergoing a major editorial reorganization in 2024, merging with the Quaderni di Storia della Fisica journal. This merger provides an opportunity to reflect on the scope of the new journal and how the distinct visions of EPJH and the Quaderni can be joined while respecting their traditions. EPJH focuses on historical studies of contemporary physics and aims to generate fruitful interaction between physicists and historians. The new EPJH will extend its scope to earlier historical periods and aims to be a central platform for researchers in the field of the history of physics. The journal also plans to introduce new formats for contributions, such as short communications and tandem papers co-written by physicists and historians. The editorial team is excited to embark on this journey with the readers. [Extracted from the article]

In a 1936 manuscript submitted to the Physical Review, Albert Einstein and Nathan Rosen famously claimed that gravitational waves do not exist. It has generally been assumed that there was a conceptual error underlying this fallacious claim. It will be shown, through a detailed study of the extant referee report, that this claim was probably only the result of a calculational error, the accidental use of a pathological coordinate transformation. [ABSTRACT FROM AUTHOR]

Background: Documenting perpetrators of human rights violations enables effective prosecution and can help prevent future atrocities. Doing so calls for collecting reliable data using verifiable and transparent methodology. We present methods used to document crimes and identify alleged perpetrators implicated in the 2017 attacks against Rohingya civilians in Myanmar. The findings and lessons-learned have relevance to contemporary crises with widespread atrocities. Methods: A mixed-methods assessment conducted from May to July 2018 included: (1) cross-sectional quantitative surveys among leaders of affected hamlets in northern Rakhine State, (2) qualitative interviews to record hamlet-level accounts, and (3) clinical evaluations of survivors of violence. Survey respondents who reported violence and destruction in each hamlet were asked to identify perpetrators of those acts, including known role or affiliation. The reported names were reviewed for clarity and divergent spellings, repeated references were aggregated, and the names and roles were analyzed and classified by location and affiliation. Results: 143 individuals were implicated in atrocities committed across three Northern Rakhine townships. Each was independently identified by at least three separate survey respondents as directly committing violence or destruction in their hamlet of origin, or as witnessed while fleeing to Bangladesh. Two-thirds (69%) of identified perpetrators were reported by four or more participants and 47% by five or more. Some form of additional identifying information, was provided for 85% of names. The most common affiliations were: Myanmar army (n = 40), Border Guard Police (n = 32), Village Tract Administrators (n = 17), and extremists (n = 25). Conclusions: The methodology presented here yielded a unique record of individuals purported to have directly committed acts of violence and destruction in Rakhine State in August 2017, forming the most extensive record of individuals implicated in ground-level perpetration of those crimes. This methodology can play a key role in accountability mechanisms for the Rohingya, and in other settings in which perpetrators are many and documentation of their crimes is difficult. The use of survey methods and standardized data collection amongst affected populations to comprehensively characterize crimes committed and to identify individuals implicated in those crimes can serve as a key tool in documentation and an important component of accountability. [ABSTRACT FROM AUTHOR]

The article discusses the unjust nature of underresourced health systems that are tasked with providing care to refugee populations across the globe. Topics covered include how individuals displaced by conflict and violence continue to bear the burdens of war decades later, the challenges of providing quality medical and surgical care for elderly patients in refugee camp settings and the population's absence in global surveys and health data.

This paper starts from the observation that the major hallmarks in the history of quantum mechanics centrally involved light and radiation. Consequently, we ask how precisely did concepts and ideas from radiation theory define the creation of quantum mechanics? And why was it a quantum theory of mechanics and not a quantum theory of electrodynamics that was crafted in the years 1925/26? Following these questions, this paper provides a reading of the history of the old quantum theory from the perspective of radiation. We argue that both wave and matrix mechanics, while emerging from widely different trajectories, emerged as spin-offs from nascent, ultimately unsuccessful quantum theories of radiation. We discuss the epistemological implications of this development for the historical and philosophical analysis of quantum mechanics and quantum field theory. [ABSTRACT FROM AUTHOR]

We reconstruct the genesis of the CPT theorem in quantum field theory from the first proofs of the spin-statistics theorem in 1939/1940 to the discovery of parity violation in 1957. Centrally, we highlight that the original motivation for pursuing the CPT theorem lay primarily in the attempt to identify the correct formulation of time reversal in relativistic quantum field theories. [ABSTRACT FROM AUTHOR]

This paper argues that non-empirical physics, as paradigmatically embodied by string theory, is a conservative research program, in spite of appearances. John Wheeler's 1950s research program of "daring conservatism" is identified as another non-empirical research program that checks all the same boxes as string theory. This case study is used to further analyze the connection between conservatism and a non-empirical approach. It is concluded that the prime difficulty of non-empirical physics is not that it involves unbridled speculation, but that the lack of empirical input prevents it from achieving revolutionary progress. [ABSTRACT FROM AUTHOR]

The article offers information on the innovations in public health delivery made by Pakistan. Topics discussed include school based mental health program and a community-based perinatal and newborn care program, which improved population health in Pakistan; expanding vaccine coverage targets for major childhood diseases, including diphtheria, pertussis, tetanus, hepatitis B; and an economic impact assessment of neglected tropical diseases (NTDs) in Pakistan.

An editorial is presented on climate change and its effect on infections induced by heminths. It highlights the significant role of the changes in the prospective activity of the parasitic worm's species as well as the emergence and downfall. It also outlines their management through vector control, biotechnology and mass drug administration (MDA).

The article offers information the quantum gravity meeting that was held in Copenhagen, Denmark in 1957. It mentions that three physicists met at the Institute for Theoretical Physics, the institute directed by Niels Bohr to discuss quantum theories of the gravitational field. It mentions that the meeting had been partially funded by the U.S. Air Force. It states that the document was deposited at the Aage Petersen Collection of Reprints and Manuscripts.

An introduction to the journal is presented in which the editor discusses various reports in the issue on the topics including the physicist, Albert Einstein's theory of gravitation, the field-theoretic law focused on energy-momentum distribution of matter and the history of General Relativity.

The preparticipation evaluation (PPE) is a widely used tool for detecting health conditions that may delay or disqualify athletic participation. The medical interview is the most valuable tool for identifying athletes who may be at increased risk for injury. Physical examination is tailored to identifying cardiac abnormalities or factors that may place an athlete at increased risk for injury. Although practiced in Europe, universal cardiac screening with electrocardiography is not currently recommended in the United States largely due to the high rate of false-positive results. Neuropsychological testing for management of concussion and laboratory testing for sickle cell trait may be indicated in select groups of athletes. Health care providers should view the PPE as a chance for anticipatory guidance and athlete-directed health counseling. Despite widespread acceptance of the PPE, the quality of such examinations varies significantly, which is an area for possible improvement and further research. [ABSTRACT FROM AUTHOR]

After an initial burst of excitement about its extraordinary implications for our concept of space and time, the theory of general relativity underwent a thirty-year period of stagnation, during which only a few specialists worked on it, achieving little progress. In the aftermath of World War II, however, general relativity gradually re-entered the mainstream of physics, attracting an increasing number of practitioners and becoming the basis for the current standard theory of gravitation and cosmology-a process Clifford Will baptized the Renaissance of General Relativity. The recent detection of gravitational radiation by the LIGO experiment can be seen as one of the most outstanding achievements in this long-lasting historical process. In the paper, we present a new multifaceted historical perspective on the causes and characteristics of the Renaissance of General Relativity, focusing in particular on the case of gravitational radiation in order to illustrate this complex and far-reaching process. [ABSTRACT FROM AUTHOR]

In the 1970s, the reinterpretation of renormalization group techniques in terms of effective field theories and their subsequent rapid development led to a major reinterpretation of the entire renormalization program, originally formulated in the late 1940s within quantum electrodynamics (QED). A more gradual shift in its interpretation, however, occurred already in the early-to-mid-1950s when renormalization techniques were transferred to solid-state and nuclear physics and helped establish the notion of effective or quasi-particles, emergent entities that are not to be found in the original, microscopic description of the theory. We study how the methods of QED, when applied in different contexts, gave rise to this ontological reinterpretation. [ABSTRACT FROM AUTHOR]

The history of the theory of general relativity presents unique features. After its discovery, the theory was immediately confirmed and rapidly changed established notions of space and time. The further implications of general relativity, however, remained largely unexplored until the mid 1950s, when it came into focus as a physical theory and gradually returned to the mainstream of physics. This essay presents a historiographical framework for assessing the history of general relativity by taking into account in an integrated narrative intellectual developments, epistemological problems, and technological advances; the characteristics of post-World War II and Cold War science; and newly emerging institutional settings. It argues that such a framework can help us understand this renaissance of general relativity as a result of two main factors: the recognition of the untapped potential of general relativity and an explicit effort at community building, which allowed this formerly disparate and dispersed field to benefit from the postwar changes in the scientific landscape. [ABSTRACT FROM AUTHOR]

Sidney Dancoff׳s paper “On Radiative Corrections for Electron Scattering” is generally viewed in the secondary literature as a failed attempt to develop renormalized quantum electrodynamics (QED) a decade early, an attempt that failed because of a mistake that Dancoff made. I will discuss Dancoff׳s mistake and try to reconstruct why it occurred, by relating it to the usual practices of the quantum field theory of his time. I will also argue against the view that Dancoff was on the verge of developing renormalized QED and will highlight the conceptual divides that separate Dancoff׳s work from the QED of the late 1940s. I will finally discuss how the established view of Dancoff׳s paper came to be and how the reading of this specific anecdote relates to more general assessments of the conceptual advances of the late 1940s (covariant techniques, renormalization), in particular to their assessment as being conservative rather than revolutionary. [ABSTRACT FROM AUTHOR]

This essay argues that the most fruitful place for historians of science to look for and investigate science’s imagined pasts is in the literature reviews and bibliographies of scientific papers. [ABSTRACT FROM AUTHOR]

BACKGROUND AND OBJECTIVES: The 2010 Affordable Care Act mandates that health insurance companies make those up to age 26 eligible for their parents' policies. Thirty-four states previously enacted similar laws. The authors sought to examine the impact on access to care of state laws extending eligibility of parents' insurance to young adults. METHODS: By using a difference-in-differences analysis, we examined the 2002-2004 and 2008-2009 Behavior Risk Factor Surveillance System to compare 3 states enacting laws in 2005 or 2006 with 17 states that have not enacted laws on 4 outcomes: self-reported health insurance coverage, identification of a personal physician/clinician, physical exam from a physician within the past 2 years, and forgoing care in the past year due to cost. RESULTS: For each outcome there was differential improvement among states enacting laws compared with states without laws. Health insurance differentially increased 0.2% (95% confidence interval [CI], -3.8% to 4.2%), from 67.6% to 68.1% pre-post in states enacting laws and from 68.5% to 68.7% in states without. Personal physician/ clinician identification differentially increased 0.9% (95% CI -3.1% to 5.0%), from 62.4% to 65.5% in states enacting laws and from 58.0% to 60.2% in states without. Recent physical exams differentially increased significantly 4.6% (95% CI, 0%-9.2%), from 77.3% to 81.2% in states enacting laws and from 76.2% to 75.5% in states without. Forgone care due to cost differentially decreased significantly 3.9% (95% CI, -0.3% to -7.5%), from 20.4% to 18.2% in states enacting laws and from 17.8% to 19.4% in states without. CONCLUSIONS: States that expanded eligibility to parents' insurance in 2005 or 2006 experienced improvements in access to care among young adults. [ABSTRACT FROM AUTHOR]

Background: In both Europe and the US, resident physician work hour reduction has been a source of controversy within academic medicine. In 2008, the Institute of Medicine (IOM) recommended a reduction in resident physician work hours. We sought to assess the American public perspective on this issue. Methods: We conducted a national survey of 1,200 representative members of the public via random digit telephone dialing in order to describe US public opinion on resident physician work hour regulation, particularly with reference to the IOM recommendations. Results: Respondents estimated that resident physicians currently work 12.9-h shifts (95% CI 12.5 to 13.3 h) and 58.3-h work weeks (95% CI 57.3 to 59.3 h). They believed the maximum shift duration should be 10.9 h (95% CI 10.6 to 11.3 h) and the maximum work week should be 50 h (95% CI 49.4 to 50.8 h), with 1% approving of shifts lasting >24 h (95% CI 0.6% to 2%). A total of 81% (95% CI 79% to 84%) believed reducing resident physician work hours would be very or somewhat effective in reducing medical errors, and 68% (95% CI 65% to 71%) favored the IOM proposal that resident physicians not work more than 16 h over an alternative IOM proposal permitting 30-h shifts with ≥5 h protected sleep time. In all, 81% believed patients should be informed if a treating resident physician had been working for >24 h and 80% (95% CI 78% to 83%) would then want a different doctor. Conclusions: The American public overwhelmingly favors discontinuation of the 30-h shifts without protected sleep routinely worked by US resident physicians and strongly supports implementation of restrictions on resident physician work hours that are as strict, or stricter, than those proposed by the IOM. Strong support exists to restrict resident physicians' work to 16 or fewer consecutive hours, similar to current limits in New Zealand, the UK and the rest of Europe. [ABSTRACT FROM AUTHOR]

It has recently been speculated that the solar neutrino mixing angle is connected to the golden ratio ϕ. Two such proposals have been made, cot θ12 = ϕ and cos θ12 = ϕ/2. We compare these ansätze and discuss a model leading to cos θ12 = ϕ/2 based on the dihedral group D10. This symmetry is a natural candidate because the angle in the expression cos θ12 = ϕ/2 is simply τ/5, or 36°. This is the exterior angle of a decagon and D10 is its rotational symmetry group. We also estimate radiative corrections to the golden ratio predictions. [ABSTRACT FROM AUTHOR]

Kidney epithelia develop from the metanephric mesenchyme after receiving inductive signals from the ureteric bud and from the renal stroma. However, it is not clear how these signals induce the different types of epithelia that make up the nephron. To investigate inductive signaling, we have isolated clusters of epithelial progenitors from the metanephric mesenchyme, thereby separating them from the renal stroma. When the isolated progenitors were treated with the ureteric bud factor LIF, they expressed epithelial proteins (ZO-1, E-cadherin, laminin α5) and produced nephrons (36 glomeruli with 58 tubules), indicating that they are the target of inductive signaling from the ureteric bud, and that renal stroma is not absolutely required for epithelial development in vitro. In fact, stroma-depleted epithelial progenitors produced sevenfold more glomeruli than did intact metanephric mesenchyme (5 glomeruli, 127 tubules). Conversely, when epithelial progenitors were treated with both LIF and proteins secreted from a renal stromal cell line, glomerulogenesis was abolished but tubular epithelia were expanded (0 glomeruli, 47 tubules). Hence, by isolating epithelial progenitors from the metanephric mesenchyme, we show that they are targeted by factors from the ureteric bud and from the renal stroma, and that epithelial diversification is stimulated by the ureteric bud and limited by renal stroma. [Copyright &y& Elsevier]

The article discusses the authors' views about the importance of hospital awards and recognition programs in the U.S. as of 2017, and it mentions managerial culture, hospital performance, and the relationships between hospitals, public health agencies, and other community partners in America. The American Hospital Association's (AHA's) Nova Award is addressed, along with the U.S. Patient Protection and Affordable Care Act, community health improvement, and several other hospital awards.

Structured light metrology provides a precise and efficient digital reconstruction of real-world objects through projected light patterns and a camera system. However, conducting measurements through these systems often requires time-intensive manual setting of input measurement parameters that may not be generalizable across a wide range of objects. Automating the steps involved in optimizing these parameters can significantly improve the quality of measured data. This work presents a digital twin to automate and refine measurements based on ray-tracing simulations that reveal the best (combination of) exposure time(s). We also conduct operational verification of this approach by comparing the exposure time search conducted by experienced operators against our tool. More broadly, the optimization metric we developed and implemented is platform-independent and thus can serve to assess any structured light measurement and/or rank competing scanners. Lastly, it is straightforward to extend this approach for light-matter interactions in any system of interest. [Display omitted] • A platform-independent methodology for Digital twin of Structured light metrology system is presented. • Selection of Optimal Exposure time(s) is automated and demonstrated with use cases. • Proposed measurement coverage quality metric is suitable for benchmarking structured light measurement systems. • Coverage quality metric can be used to study effects of other measurement parameters. [ABSTRACT FROM AUTHOR]

Presents a letter to the editor about breast tissue development in obese children.

Endothelial progenitor cells (EPCs) contribute to de novo angiogenesis, tissue regeneration, and remodeling. Interleukin 10 (IL‐10), an anti‐inflammatory cytokine that primarily signals via STAT3, has been shown to drive EPC recruitment to injured tissues. Our previous work demonstrated that overexpression of IL‐10 in dermal wounds promotes regenerative tissue repair via STAT3‐dependent regulation of fibroblast‐specific hyaluronan synthesis. However, IL‐10's role and specific mode of action on EPC recruitment, particularly in dermal wound healing and neovascularization in both normal and diabetic wounds, remain to be defined. Therefore, inducible skin‐specific STAT3 knockdown mice were studied to determine IL‐10's impact on EPCs, dermal wound neovascularization and healing, and whether it is STAT3‐dependent. We show that IL‐10 overexpression significantly elevated EPC counts in the granulating wound bed, which was associated with robust capillary lumen density and enhanced re‐epithelialization of both control and diabetic (db/db) wounds at day 7. We noted increased VEGF and high C‐X‐C motif chemokine 12 (CXCL12) levels in wounds and a favorable CXCL12 gradient at day 3 that may support EPC mobilization and infiltration from bone marrow to wounds, an effect that was abrogated in STAT3 knockdown wounds. These findings were supported in vitro. IL‐10 promoted VEGF and CXCL12 synthesis in primary murine dermal fibroblasts, with blunted VEGF expression upon blocking CXCL12 in the media by antibody binding. IL‐10‐conditioned fibroblast media also significantly promoted endothelial sprouting and network formation. In conclusion, these studies demonstrate that overexpression of IL‐10 in dermal wounds recruits EPCs and leads to increased vascular structures and faster re‐epithelialization. [ABSTRACT FROM AUTHOR]

Background Mycobacterium tuberculosis (Mtb) strains resistant to isoniazid and rifampin (multidrug-resistant tuberculosis [MDR-TB]) are increasingly reported worldwide, requiring renewed focus on the nuances of drug resistance. Patients with low-level moxifloxacin resistance may benefit from higher doses, but limited clinical data on this strategy are available. Methods We conducted a 5-year observational cohort study of MDR-TB patients at a tertiary care center in India. Participants with Mtb isolates resistant to isoniazid, rifampin, and moxifloxacin (at the 0.5 µg/mL threshold) were analyzed according to receipt of high-dose moxifloxacin (600 mg daily) as part of a susceptibility-guided treatment regimen. Univariable and multivariable Cox proportional hazard models assessed the relationship between high-dose moxifloxacin and unfavorable treatment outcomes. Results Of 354 participants with MDR-TB resistant to moxifloxacin, 291 (82.2%) received high-dose moxifloxacin. The majority experienced good treatment outcomes (200 [56.5%]), which was similar between groups (56.7% vs 54.0%, P  = .74). Unfavorable outcomes were associated with greater extent of radiographic disease, lower initial body mass index, and concurrent treatment with fewer drugs with confirmed phenotypic susceptibility. Treatment with high-dose moxifloxacin was not associated with improved outcomes in either unadjusted (hazard ratio [HR], 1.2 [95% confidence interval {CI},.6–2.4]) or adjusted (HR, 0.8 [95% CI,.5–1.4]) models but was associated with joint pain (HR, 3.2 [95% CI, 1.2–8.8]). Conclusions In a large observational cohort, adding high-dose (600 mg) moxifloxacin to a drug susceptibility test–based treatment regimen for MDR-TB was associated with increased treatment-associated side effects without improving overall outcomes and should be avoided for empiric treatment of moxifloxacin-resistant MDR-TB. [ABSTRACT FROM AUTHOR]

Hyaluronan (HA) is abundant in the skin; while HA can be synthesized by the synthases (HAS1-3), HAS2 is the leading contributor. Dysregulation and accumulation of HA is implicated in the pathogenesis of diseases such as keloid scarring, lymphedema and metastatic melanoma. To understand how HA synthesis contributes to skin physiology, and pathologic and fibrotic disorders, we propose the development of skin-specific HA inhibition model, which tests an optimal delivery system of topical 4-methylumbelliferone (4-MU). A design-of-experiments (DOE) approach was employed to develop an optimal 4-MU skin-delivery formulation comprising propylene glycol, ethanol, and water, topically applied to dorsal skin in male and female C57BL/6J wildtype mice to determine the effect on HAS gene expression and HA inhibition. Serum and skin samples were analyzed for HA content along with analysis of expression of HAS1-3, hyaluronidases (HYAL 1-2), and KIAA1199. Using results from DOE and response surface methodology with genetic algorithm optimization, we developed an optimal topical 4-MU formulation to result in -70% reduction of HA in dorsal skin, with validation demonstrating ~50% reduction in HA in dorsal skin. 4-MU topical application resulted in significant decrease in skin HAS2 expression in female mice only. Histology showed thicker dermis in male mice, whereas female mice had thinner dermal layer with more adiposity; and staining for HAbinding protein showed that topical 4-MU resulted in breakdown in HA. Our data suggest a topical 4-MU formulation-based dermal HA inhibition model that would enable elucidating the skin-specific effects of HA in normal and pathologic states. [ABSTRACT FROM AUTHOR]

Abstract: Objectives: To strengthen the evidence-base for policy and practice for support of children outside of family care requires effective, efficient and sustainable mechanisms for monitoring and evaluation. Toward that end, two core questions guided a systematic review of evidence: What strategies are appropriate for monitoring the needs and circumstances of children outside of family care? What strategies are suitable for evaluating the impact of the programs intended to serve such children? Methods: A structured document search and review process was implemented within the context of the U.S. Government Evidence Summit on Protecting Children Outside of Family Care of December 2011. Through successive review phases, initially using structured screening criteria, followed by thematic review by an expert panel, 73 documents were identified for analysis. Results: Analysis of models and strategies indicates that: (1) tools are available for assessment of children''s needs, but require refining to accommodate contextual demands; (2) well-designed evaluations are able to identify the influence of assistance; (3) long-term follow-up is crucial to developing a strong evidence-base on effective strategies; and (4) insights into systems-wide monitoring mechanisms are emerging. In addition to describing key components of monitoring and evaluation strategies, findings draw attention to the evaluation of children''s resiliency and protective factors, community based monitoring and the role of caregivers, as well as concerns over the stigmatization of children (through data collection methodologies encouraging the ‘labeling’ of children) and the importance of children''s participation. Conclusions: Fostering a stronger evidence-base to improve protection for vulnerable children requires evaluations that are integrated into program development, use context-appropriate methodologies able to assess intervention scalability and employ more longitudinal designs to explore children''s trajectories. Further, future programming will benefit from systems-wide data coordination and international comparisons, research that emphasizes coping and resilience mechanisms, and children''s participation in monitoring and evaluation. [Copyright &y& Elsevier]