425 results match your criteria: "Harvard University. Cambridge[Affiliation]"

Sulfenyl fluorides are organic compounds of sulfur in formal oxidation state +2 with the formula R-S-F. Although the chloride, bromide, and iodide analogues have been extensively described in the literature, arenesulfenyl fluorides remain essentially unstudied. These structures have been implicated as putative intermediates in established processes to access polyfluorinated sulfur species; however, definitive and direct evidence of their existence has not been obtained, nor has a systematic understanding of their reactivity.

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The catalytic and plasmonic properties of bimetallic gold-palladium (Au-Pd) nanoparticles (NPs) critically depend on the distribution of the Au and Pd atoms inside the nanoparticle bulk and at the surface. Under operating conditions, the atomic distribution is highly dynamic. Analyzing gas induced redistribution kinetics at operating temperatures is therefore key in designing and understanding the behavior of Au-Pd nanoparticles for applications in thermal and light-driven catalysis, but requires advanced characterization strategies.

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Antibody-drug conjugates (ADCs), chemotherapeutic agents conjugated to an antibody to enhance their targeted delivery to tumors, represent a significant advancement in cancer therapy. ADCs combine the precise targeting capabilities of antibodies and the potent cell-killing effects of chemotherapy, allowing for enhanced cytotoxicity to tumors while minimizing damage to healthy tissues. Here, we provide an overview of the current clinical landscape of ADCs, highlighting 11 U.

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Directionality theory and the origin of life.

R Soc Open Sci

November 2024

Department of Organismic and Evolutionary Biology, Harvard University Cambridge, Cambridge, MA 02138, USA.

The origin of cellular life can be described in terms of the transition from inorganic matter to the emergence of cooperative assemblies of organic matter: DNA and proteins, capable of replication and metabolism. Directionality theory is a mathematical theory of the collective behaviour of networks of organic matter: activated macromolecules, cells and higher organisms. Evolutionary entropy, a generalization of the thermodynamic entropy of Boltzmann, is a statistical measure of the cooperativity of the biotic components.

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The microfossil record contains abundant, diverse, and well-preserved fossils spanning multiple trophic levels from primary producers to apex predators. In addition, microfossils often constitute and are preserved in high abundances alongside continuous high-resolution geochemical proxy records. These characteristics mean that microfossils can provide valuable context for understanding the modern climate and biodiversity crises by allowing for the interrogation of spatiotemporal scales well beyond what is available in neo-ecological research.

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This case underscores the importance of recognizing the potential link between hormonal fluctuations during the menstrual cycle and idiopathic intracranial hypertension (IIH), which could lead to spontaneous cerebrospinal fluid (CSF) rhinorrhea. Eliciting a history of intermittent clear rhinorrhea with the onset of menstrual cycle if presenting with menstrual migraines could allow for a more prompt diagnosis and treatment of IIH and CSF leak. Early diagnosis and intervention are crucial to prevent serious complications.

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Background: Discrimination may contribute to sleep health disparities among women, yet limited research has investigated the association between discrimination and insomnia with short sleep.

Methods And Results: Among a racially and ethnically diverse sample of women (N=25 920; mean age, 72.2±6.

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Meristic traits are often treated as distinct phenotypes that can be used to differentiate and delineate recently diverged species. For instance, the number of lateral line scales and vertebrae, two traits that vary substantially among Neotropical Heroine cichlid species, have been previously suggested to co-evolve. These meristic traits could co-evolve due to shared adaptive, developmental, or genetic factors.

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Due to their large size and obligate nature, Cymothoid isopods inflict a high degree of tissue damage to fish. Still, they are understudied at an ecosystem level despite their global presence and ecological role. In this work, we collected fish host-isopod parasite data, along with their life history and ecological traits, from the northern part of the east coast of India and investigated patterns in host specialisation and preference of isopod parasites using a trait-based network perspective.

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Nucleic acid amplification testing (NAAT) remains one of the most reliable methods for pathogen identification. However, conventional bulk NAATs may not be sufficiently fast or sensitive enough for the detection of clinically-relevant pathogens in point-of-care testing. Here, we have developed a digital droplet RT-LAMP (ddRT-LAMP) assay that rapidly and quantitatively detects the SARS-CoV-2 viral E gene in microfluidic drops.

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Metagenome comparison (MC): A new framework for detecting unique/enriched OMUs (operational metagenomic units) derived from whole-genome sequencing reads.

Comput Biol Med

September 2024

Faculty of Arts and Sciences Harvard University Cambridge, MA, 02138, USA; Microbiome Medicine and Advanced AI Lab, Cambridge, MA, 02138, USA; Computational Biology and Medical Ecology Lab Kunming Institute of Zoology Chinese Academy of Sciences, China. Electronic address:

Background: Current methods for comparing metagenomes, derived from whole-genome sequencing reads, include top-down metrics or parametric models such as metagenome-diversity, and bottom-up, non-parametric, model-free machine learning approaches like Naïve Bayes for k-mer-profiling. However, both types are limited in their ability to effectively and comprehensively identify and catalogue unique or enriched metagenomic genes, a critical task in comparative metagenomics. This challenge is significant and complex due to its NP-hard nature, which means computational time grows exponentially, or even faster, with the problem size, rendering it impractical for even the fastest supercomputers without heuristic approximation algorithms.

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Introduction: Fragility analysis is a method of further characterising the robustness of statistical outcomes. This study evaluates the statistical fragility of randomised controlled trials (RCTs) comparing patellar resurfacing versus non-patellar surfacing in total knee arthroplasty (TKA).

Methods: PubMed, MEDLINE and EMBASE were searched for RCTs comparing outcomes in TKA based on patellar resurfacing.

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Systematic revision of the South American "" (Opiliones, Laniatores, Triaenonychidae).

Zookeys

July 2024

División Aracnología, Museo Argentino de Ciencias Naturales-CONICET, Av. Ángel Gallardo 470, C1405DJR Buenos Aires, Argentina Museo Argentino de Ciencias Naturales-CONICET Buenos Aires Argentina.

The genus has long been the most speciose within the Opiliones family Triaenonychidae, comprising 63 species and subspecies distributed across New Zealand and South America. Recent molecular studies utilizing Sanger sequencing and ultraconserved elements (UCEs) have indicated that this genus is not monophyletic, and true are actually confined to New Zealand. Here, the morphology of all South American triaenonychids is re-examined and DNA sequence data compiled from three markers (18S rRNA, 28S rRNA and cytochrome oxidase subunit I) for a large number of triaenonychid species, including specimens from all areas with species currently and formerly classified in to reassess their phylogenetic position.

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Indonesia faces significant air quality issues due to multiple emissions sources, including rapid urbanization and peatland fires associated with agricultural land management. Limited prior research has estimated the episodic shock of intense fires on morbidity and mortality in Indonesia but has largely ignored the impact of poor air quality throughout the year on biomarkers of cardiovascular disease risk. We conducted a cross-sectional study of the association between particulate matter less than 2.

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Article Synopsis
  • The study investigates the use of a novel AI model to assess the surgical skill of physicians performing robotic distal gastrectomy (RDG) by identifying different surgical instruments used during the procedure.
  • Analyzing 55 robotic surgical videos, the AI model demonstrated strong accuracy metrics, with an average accuracy of 87.2% in recognizing instruments and a significant difference in usage patterns between experienced and non-experienced surgeons.
  • This research highlights the potential of AI technology in objectively evaluating surgical skills, making the process of assessing proficiency in RDG more accessible and unbiased.
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Migratory birds experience changes in their environment and diet during seasonal migrations, thus requiring interactions between diet and gut microbes. Understanding the co-evolution of the host and gut microbiota is critical for elucidating the rapid adaptations of avian gut microbiota. However, dynamics of gut microbial adaptations concerning elevational migratory behavior, which is prevalent but understudied in montane birds remain poorly understood.

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Background: Current protocols generate highly pure human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) in vitro that recapitulate characteristics of mature in vivo cardiomyocytes. Yet, a risk of arrhythmias exists when hiPSC-CMs are injected into large animal models. Thus, understanding hiPSC-CM maturational mechanisms is crucial for clinical translation.

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Object: Amplification of the epidermal growth factor receptor (EGFR) and its active mutant type III (EGFRvIII), frequently occurr in glioblastoma (GBM), contributing to chemotherapy and radiation resistance in GBM. Elucidating the underlying molecular mechanism of temozolomide (TMZ) resistance in EGFRvIII GBM could offer valuable insights for cancer treatment.

Methods: To elucidate the molecular mechanisms underlying EGFRvIII-mediated resistance to TMZ in GBM, we conducted a comprehensive analysis using Gene Expression Omnibus and The cancer genome atlas (TCGA) databases.

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We show that neural networks can implement reward-seeking behavior using only local predictive updates and internal noise. These networks are capable of autonomous interaction with an environment and can switch between explore and exploit behavior, which we show is governed by attractor dynamics. Networks can adapt to changes in their architectures, environments, or motor interfaces without any external control signals.

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Stepwise metalation of the hexadentate ligand LH (LH = 1,3,5-CH(NHCH--NHSiMeBu)) affords bimetallic trinuclear clusters (L)FeZn(thf) and (L)FeZn(py). Reactivity studies were pursued to understand metal atom lability as the clusters undergo ligand substitution, redox chemistry, and group transfer processes. Chloride addition to (L)FeZn(thf) resulted in a mixture of species including both all-zinc and all-iron products.

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Four new inquiline social parasites are described in the dolichoderine ant genus from the Nearctic region, and keys are provided for queens and males of the Nearctic species. The new social parasite species represent the first inquiline species in the genus and the first confirmed inquilines known from the ant subfamily Dolichoderinae. The four new species appear to be workerless inquilines that exploit a single host, (Say), and they represent at least two distinct life history syndromes.

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Tropical forest phenology directly affects regional carbon cycles, but the relation between species-specific and whole-canopy phenology remains largely uncharacterized. We present a unique analysis of historical tropical tree phenology collected in the central Congo Basin, before large-scale impacts of human-induced climate change. Ground-based long-term (1937-1956) phenological observations of 140 tropical tree species are recovered, species-specific phenological patterns analyzed and related to historical meteorological records, and scaled to characterize stand-level canopy dynamics.

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Common distributional patterns have provided the foundations of our knowledge of Neotropical biogeography. A distinctive pattern is the "circum-Amazonian distribution", which surrounds Amazonia across the forested lowlands south and east of the basin, the Andean foothills, the Venezuelan Coastal Range, and the Tepuis. The underlying evolutionary and biogeographical mechanisms responsible for this widespread pattern of avian distribution have yet to be elucidated.

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