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2.
Protist ; 174(5): 125983, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37573812

RESUMO

Based on scanning electron microscopy observations, a new species of the coccolithophore genus Calciopappus (Syracosphaeraceae, Prymnesiophyceae) is described from the surface waters off Bergen and from the lower photic zone of sub-tropical and tropical waters. Morphological, coccolith rim structure and biometric analyses strongly support separation of this morphotype from the two described Calciopappus species, but inclusion of it within the genus. The new form differs from the other species in being noticeably smaller and in morpho-structural details of each of the three coccolith types that form the coccosphere: (1) the body coccoliths have an open central area; (2) the whorl coccoliths have a wide central opening and two thumb-like protrusions; and (3) the appendage coccoliths are curved. On this basis, the species is formally described as Calciopappus curvus sp. nov., its systematic affinity is discussed and compared with other extant coccolithophores.


Assuntos
Haptófitas , Microscopia Eletrônica de Varredura
3.
Anaesth Intensive Care ; 51(4): 274-280, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37314224

RESUMO

High-fidelity models are required for technical mastery of bronchoscopic procedures in the fields of anaesthesia, intensive care, surgery and respiratory medicine. Our group has created a three-dimensional (3D) airway model prototype to emulate physiological and pathological movement. Developed from the concepts of our previously described 3D printed paediatric trachea for airway management training, this model produces movements created by injection of air or saline through a side Luer Lock port. The anaesthesia and intensive care applications of the model could include bronchoscopic navigation through narrow pathologies and simulated bleeding tumours. It also has the potential to be used to practice placement of a double-lumen tube and broncho-alveolar lavage among other procedures. For surgical training, the model has high tissue realism and allows for rigid bronchoscopy. The novel and high-fidelity 3D printed airway model with dynamic pathologies represents capability to provide both generic and patient-specific advancement for all modes of anatomical representation. The prototype illustrates the potential of combining the fields of industrial design with clinical anaesthesia.


Assuntos
Anestesia , Treinamento por Simulação , Criança , Humanos , Modelos Anatômicos , Impressão Tridimensional , Broncoscopia , Treinamento por Simulação/métodos
4.
Sci Adv ; 9(24): eadf8748, 2023 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-37327341

RESUMO

Staphylococcus aureus is the leading cause of skin and soft tissue infections and is a major health burden due to the emergence of antibiotic-resistant strains. To address the unmet need of alternative treatments to antibiotics, a better understanding of the protective immune mechanisms against S. aureus skin infection is warranted. Here, we report that tumor necrosis factor (TNF) promoted protection against S. aureus in the skin, which was mediated by bone marrow-derived immune cells. Furthermore, neutrophil-intrinsic TNF receptor (TNFR) signaling directed immunity against S. aureus skin infections. Mechanistically, TNFR1 promoted neutrophil recruitment to the skin, whereas TNFR2 prevented systemic bacterial dissemination and directed neutrophil antimicrobial functions. Treatment with a TNFR2 agonist showed therapeutic efficacy against S. aureus and Pseudomonas aeruginosa skin infections, which involved increased neutrophil extracellular trap formation. Our findings revealed nonredundant roles for TNFR1 and TNFR2 in neutrophils for immunity against S. aureus and can be therapeutically targeted for protection against bacterial skin infections.


Assuntos
Neutrófilos , Infecções Estafilocócicas , Humanos , Staphylococcus aureus , Receptores Tipo I de Fatores de Necrose Tumoral , Receptores Tipo II do Fator de Necrose Tumoral , Infecções Estafilocócicas/tratamento farmacológico
5.
ISME J ; 17(4): 630-640, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36747097

RESUMO

Marine phytoplankton play important roles in the global ecosystem, with a limited number of cosmopolitan keystone species driving their biomass. Recent studies have revealed that many of these phytoplankton are complexes composed of sibling species, but little is known about the evolutionary processes underlying their formation. Gephyrocapsa huxleyi, a widely distributed and abundant unicellular marine planktonic algae, produces calcified scales (coccoliths), thereby significantly affects global biogeochemical cycles via sequestration of inorganic carbon. This species is composed of morphotypes defined by differing degrees of coccolith calcification, the evolutionary ecology of which remains unclear. Here, we report an integrated morphological, ecological and genomic survey across globally distributed G. huxleyi strains to reconstruct evolutionary relationships between morphotypes in relation to their habitats. While G. huxleyi has been considered a single cosmopolitan species, our analyses demonstrate that it has evolved to comprise at least three distinct species, which led us to formally revise the taxonomy of the G. huxleyi complex. Moreover, the first speciation event occurred before the onset of the last interglacial period (~140 ka), while the second followed during this interglacial. Then, further rapid diversifications occurred during the most recent ice-sheet expansion of the last glacial period and established morphotypes as dominant populations across environmental clines. These results suggest that glacial-cycle dynamics contributed to the isolation of ocean basins and the segregations of oceans fronts as extrinsic drivers of micro-evolutionary radiations in extant marine phytoplankton.


Assuntos
Haptófitas , Fitoplâncton , Fitoplâncton/genética , Ecossistema , Haptófitas/genética , Oceanos e Mares , Plâncton
6.
Biomedica ; 42(Sp. 1): 79-88, 2022 05 01.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-35866732

RESUMO

INTRODUCTION: Non-communicable diseases are the leading cause of death worldwide and physical activity is a key preventive strategy to reduce them. There is a relationship between the built environment and the practice of physical activity, but little evidence as to whether those built environment interventions not initially designed for promoting physical activity actually have an impact on promoting the behavior. OBJECTIVE: To identify whether such built environment interventions were able to change physical activity in adults. MATERIALS AND METHODS: We conducted a systematic review of interventions targeting modifications to the built environment changes in urban areas. RESULTS: Out of 5,605 articles reviewed, only seven met our inclusion criteria. The seven studies found higher levels of physical activity after the interventions. CONCLUSIONS: We recommend greater specificity regarding the study design, the timeline of interventions implementation and post-intervention measurements, as well as the use of more objective measures. Finally, we point out the need to make more explicit the mechanisms of change related to the interventions assessed.


Introducción. Las enfermedades no transmisibles son la principal causa de muerte en todo el mundo y la actividad física es una estrategia preventiva clave para reducirlas. Hay una relación entre el entorno construido y la práctica de actividad física, pero poca evidencia de si las intervenciones no diseñadas en principio para promoverla, realmente tienen un impacto en ese sentido. Objetivo. Determinar si tales intervenciones en el entorno urbano pudieron cambiar la práctica de actividad física en adultos. Materiales y métodos. Se hizo una revisión sistemática de las intervenciones que apuntaban a modificar el entorno construido en zonas urbanas. Resultados. De 5.605 artículos considerados, solo siete cumplieron con nuestros criterios de inclusión y en todos ellos aumentó la actividad física después de la intervención. Conclusiones. Se recomienda que el diseño del estudio, el cronograma de implementación de las intervenciones y las mediciones posteriores sean más específicas, de manera que las medidas obtenidas sean más objetivas. Asimismo, se argumenta la necesidad de hacer más explícitos los mecanismos de cambio relacionados con las intervenciones evaluadas.


Assuntos
Ambiente Construído , Exercício Físico
7.
Biomédica (Bogotá) ; 42(supl.1): 79-88, mayo 2022. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1393997

RESUMO

Introduction: Non-communicable diseases are the leading cause of death worldwide and physical activity is a key preventive strategy to reduce them. There is a relationship between the built environment and the practice of physical activity, but little evidence as to whether those built environment interventions not initially designed for promoting physical activity actually have an impact on promoting the behavior. Objective: To identify whether such built environment interventions were able to change physical activity in adults. Materials and methods: We conducted a systematic review of interventions targeting modifications to the built environment changes in urban areas. Results: Out of 5,605 articles reviewed, only seven met our inclusion criteria. The seven studies found higher levels of physical activity after the interventions. Conclusions: We recommend greater specificity regarding the study design, the timeline of interventions implementation and post-intervention measurements, as well as the use of more objective measures. Finally, we point out the need to make more explicit the mechanisms of change related to the interventions assessed.


Introducción. Las enfermedades no transmisibles son la principal causa de muerte en todo el mundo y la actividad física es una estrategia preventiva clave para reducirlas. Hay una relación entre el entorno construido y la práctica de actividad física, pero poca evidencia de si las intervenciones no diseñadas en principio para promoverla, realmente tienen un impacto en ese sentido. Objetivo. Determinar si tales intervenciones en el entorno urbano pudieron cambiar la práctica de actividad física en adultos. Materiales y métodos. Se hizo una revisión sistemática de las intervenciones que apuntaban a modificar el entorno construido en zonas urbanas. Resultados. De 5.605 artículos considerados, solo siete cumplieron con nuestros criterios de inclusión y en todos ellos aumentó la actividad física después de la intervención. Conclusiones. Se recomienda que el diseño del estudio, el cronograma de implementación de las intervenciones y las mediciones posteriores sean más específicas, de manera que las medidas obtenidas sean más objetivas. Asimismo, se argumenta la necesidad de hacer más explícitos los mecanismos de cambio relacionados con las intervenciones evaluadas.


Assuntos
Exercício Físico , Ambiente Construído , Promoção da Saúde
9.
Acta Crystallogr F Struct Biol Commun ; 78(Pt 2): 59-65, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-35102894

RESUMO

Giardiasis is the most prevalent diarrheal disease globally and affects humans and animals. It is a significant problem in developing countries, the number one cause of travelers' diarrhea and affects children and immunocompromised individuals, especially HIV-infected individuals. Giardiasis is treated with antibiotics (tinidazole and metronidazole) that are also used for other infections such as trichomoniasis. The ongoing search for new therapeutics for giardiasis includes characterizing the structure and function of proteins from the causative protozoan Giardia lamblia. These proteins include hypothetical proteins that share 30% sequence identity or less with proteins of known structure. Here, the atomic resolution structure of a 15.6 kDa protein was determined by molecular replacement. The structure has the two-layer αß-sandwich topology observed in the prototypical endoribonucleases L-PSPs (liver perchloric acid-soluble proteins) with conserved allosteric active sites containing small molecules from the crystallization solution. This article is an educational collaboration between Hampton University and the Seattle Structural Genomics Center for Infectious Disease.


Assuntos
Giardia lamblia/química , Proteínas de Protozoários/química , Domínio Catalítico , Cristalografia por Raios X , Modelos Moleculares , Conformação Proteica , Proteínas de Protozoários/metabolismo
10.
Acta Crystallogr F Struct Biol Commun ; 78(Pt 1): 25-30, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34981772

RESUMO

Paraburkholderia xenovorans degrades organic wastes, including polychlorinated biphenyls. The atomic structure of a putative dehydrogenase/reductase (SDR) from P. xenovorans (PxSDR) was determined in space group P21 at a resolution of 1.45 Å. PxSDR shares less than 37% sequence identity with any known structure and assembles as a prototypical SDR tetramer. As expected, there is some conformational flexibility and difference in the substrate-binding cavity, which explains the substrate specificity. Uniquely, the cofactor-binding cavity of PxSDR is not well conserved and differs from those of other SDRs. PxSDR has an additional seven amino acids that form an additional unique loop within the cofactor-binding cavity. Further studies are required to determine how these differences affect the enzymatic functions of the SDR.


Assuntos
Burkholderiaceae , Redutases-Desidrogenases de Cadeia Curta , Cristalografia por Raios X , Oxirredutases/química , Redutases-Desidrogenases de Cadeia Curta/metabolismo , Especificidade por Substrato
11.
Phys Rev Lett ; 127(12): 120501, 2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34597076

RESUMO

Because of their strong and tunable interactions, Rydberg atoms can be used to realize fast two-qubit entangling gates. We propose a generalization of a generic two-qubit Rydberg-blockade gate to multiqubit Rydberg-blockade gates that involve both many control qubits and many target qubits simultaneously. This is achieved by using strong microwave fields to dress nearby Rydberg states, leading to asymmetric blockade in which control-target interactions are much stronger than control-control and target-target interactions. The implementation of these multiqubit gates can drastically simplify both quantum algorithms and state preparation. To illustrate this, we show that a 25-atom Greenberger-Horne-Zeilinger state can be created using only three gates with an error of 5.8%.

12.
Opt Express ; 29(16): 25731-25744, 2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-34614896

RESUMO

Optical Kerr effects induced by the propagation of high peak-power laser beams through real atmospheres have been a topic of interest to the nonlinear optics community for several decades. This paper proposes a new analytical model for predicting the filamentation/light channel onset distance in real atmospheres based on modulation instability model considerations. The normalized intensity increases exponentially as the beam propagates through the medium. It is hypothesized that this growth can be modeled as a weighted ratio of the Gaussian beam diameter at range to the lateral coherence radius and can be used to set the power ratio for an absorbing, turbulent, nonlinear media to estimate the beam collapse distance. Comparison of onset distance predictions with those found from computer simulation and deduced from field experiments will be presented. In addition, this model will be used with an analytical approach to quantify the expected radius of light channels resulting from self-focusing both with and without the production of a plasma filament. Finally, this paper will describe a set of 1.5-micron, variable focal length USPL field experiments. Comparisons of theoretical radius calculations to measurements from field experiments will be presented.

13.
Sci Data ; 8(1): 160, 2021 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-34183675

RESUMO

Planktonic foraminifera are a major constituent of ocean floor sediments, and thus have one of the most complete fossil records of any organism. Expeditions to sample these sediments have produced large amounts of spatiotemporal occurrence records throughout the Cenozoic, but no single source exists to house these data. We have therefore created a comprehensive dataset that integrates numerous sources for spatiotemporal records of planktonic foraminifera. This new dataset, Triton, contains >500,000 records and is four times larger than the previous largest database, Neptune. To ensure comparability among data sources, we have cleaned all records using a unified set of taxonomic concepts and have converted age data to the GTS 2020 timescale. Where ages were not absolute (e.g. based on biostratigraphic or magnetostratigraphic zones), we have used generalised additive models to produce continuous estimates. This dataset is an excellent resource for macroecological and macroevolutionary studies, particularly for investigating how species responded to past climatic changes.


Assuntos
Foraminíferos/classificação , Plâncton/classificação , Mudança Climática , Fósseis , Sedimentos Geológicos
15.
Phys Rev X ; 11(2)2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36451802

RESUMO

We induce strong nonlocal interactions in a 2D Fermi gas in an optical lattice using Rydberg dressing. The system is approximately described by a t - V model on a square lattice where the fermions experience isotropic nearest-neighbor interactions and are free to hop only along one direction. We measure the interactions using many-body Ramsey interferometry and study the lifetime of the gas in the presence of tunneling, finding that tunneling does not reduce the lifetime. To probe the interplay of nonlocal interactions with tunneling, we investigate the short-time-relaxation dynamics of charge-density waves in the gas. We find that strong nearest-neighbor interactions slow down the relaxation. Our work opens the door for quantum simulations of systems with strong nonlocal interactions such as extended Fermi-Hubbard models.

16.
Clin Infect Dis ; 72(6): 913-919, 2021 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-33033829

RESUMO

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has revolutionized the practice of ambulatory medicine, triggering rapid dissemination of digital healthcare modalities, including synchronous video visits. However, social determinants of health, such as age, race, income, and others, predict readiness for telemedicine and individuals who are not able to connect virtually may become lost to care. This is particularly relevant to the practice of infectious diseases (ID) and human immunodeficiency virus (HIV) medicine, as we care for high proportions of individuals whose health outcomes are affected by such factors. Furthermore, delivering high-quality clinical care in ID and HIV practice necessitates discussion of sensitive topics, which is challenging over video without proper preparation. We describe the "digital divide," emphasize the relevance to ID and HIV practice, underscore the need to study the issue and develop interventions to mitigate its impact, and provide suggestions for optimizing telemedicine in ID and HIV clinics.


Assuntos
COVID-19 , Doenças Transmissíveis , Infecções por HIV , Equidade em Saúde , Telemedicina , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Humanos , Políticas , SARS-CoV-2
17.
Phys Rev X ; 10(1)2020.
Artigo em Inglês | MEDLINE | ID: mdl-33364075

RESUMO

Driven-dissipative systems are expected to give rise to nonequilibrium phenomena that are absent in their equilibrium counterparts. However, phase transitions in these systems generically exhibit an effectively classical equilibrium behavior in spite of their nonequilibrium origin. In this paper, we show that multicritical points in such systems lead to a rich and genuinely nonequilibrium behavior. Specifically, we investigate a driven-dissipative model of interacting bosons that possesses two distinct phase transitions: one from a high- to a low-density phase-reminiscent of a liquid-gas transition-and another to an antiferromagnetic phase. Each phase transition is described by the Ising universality class characterized by an (emergent or microscopic) ℤ 2 symmetry. However, they coalesce at a multicritical point, giving rise to a nonequilibrium model of coupled Ising-like order parameters described by a ℤ 2 × â„¤ 2 symmetry. Using a dynamical renormalization-group approach, we show that a pair of nonequilibrium fixed points (NEFPs) emerge that govern the long-distance critical behavior of the system. We elucidate various exotic features of these NEFPs. In particular, we show that a generic continuous scale invariance at criticality is reduced to a discrete scale invariance. This further results in complex-valued critical exponents and spiraling phase boundaries, and it is also accompanied by a complex Liouvillian gap even close to the phase transition. As direct evidence of the nonequilibrium nature of the NEFPs, we show that the fluctuation-dissipation relation is violated at all scales, leading to an effective temperature that becomes "hotter" and "hotter" at longer and longer wavelengths. Finally, we argue that this nonequilibrium behavior can be observed in cavity arrays with cross-Kerr nonlinearities.

18.
Anaesth Intensive Care ; 48(3): 243-245, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32536185

RESUMO

There is a deficit of commercially available paediatric airway models for anaesthesia airway management training, particularly for infant front-of-neck access and customised airway planning. Acknowledging this, we created a three-dimensional printed prototype for an affordable, high-fidelity training device, incorporating realistic tactile feedback, reproducibility and potential for modification for specific patient pathologies. Our model, created on a Stratasys Polyjet J750™ (Rehovot, Israel) printer, is a novel and useful educational tool in paediatric airway management, and we are pleased to share access to this resource with readers. Our work adds credence to three-dimensional printing as an accessible, reproducible and pluripotent technology in clinical anaesthesia.


Assuntos
Manuseio das Vias Aéreas , Impressão Tridimensional , Traqueia , Criança , Humanos , Lactente , Israel , Modelos Anatômicos , Reprodutibilidade dos Testes
19.
Phys Rev Lett ; 125(24): 240405, 2020 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-33412027

RESUMO

Symmetry-breaking transitions are a well-understood phenomenon of closed quantum systems in quantum optics, condensed matter, and high energy physics. However, symmetry breaking in open systems is less thoroughly understood, in part due to the richer steady-state and symmetry structure that such systems possess. For the prototypical open system-a Lindbladian-a unitary symmetry can be imposed in a "weak" or a "strong" way. We characterize the possible Z_{n} symmetry-breaking transitions for both cases. In the case of Z_{2}, a weak-symmetry-broken phase guarantees at most a classical bit steady-state structure, while a strong-symmetry-broken phase admits a partially protected steady-state qubit. Viewing photonic cat qubits through the lens of strong-symmetry breaking, we show how to dynamically recover the logical information after any gap-preserving strong-symmetric error; such recovery becomes perfect exponentially quickly in the number of photons. Our study forges a connection between driven-dissipative phase transitions and error correction.

20.
Clin Infect Dis ; 70(5): 867-874, 2020 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-30994900

RESUMO

BACKGROUND: Substance use is common among people living with human immunodeficiency virus (PLWH) and a barrier to achieving viral suppression. Among PLWH who report illicit drug use, we evaluated associations between HIV viral load (VL) and reduced use of illicit opioids, methamphetamine/crystal, cocaine/crack, and marijuana, regardless of whether or not abstinence was achieved. METHODS: This was a longitudinal cohort study of PLWH from 7 HIV clinics or 4 clinical studies. We used joint longitudinal and survival models to examine the impact of decreasing drug use and of abstinence for each drug on viral suppression. We repeated analyses using linear mixed models to examine associations between change in frequency of drug use and VL. RESULTS: The number of PLWH who were using each drug at baseline ranged from n = 568 (illicit opioids) to n = 4272 (marijuana). Abstinence was associated with higher odds of viral suppression (odds ratio [OR], 1.4-2.2) and lower relative VL (ranging from 21% to 42% by drug) for all 4 drug categories. Reducing frequency of illicit opioid or methamphetamine/crystal use without abstinence was associated with VL suppression (OR, 2.2, 1.6, respectively). Reducing frequency of illicit opioid or methamphetamine/crystal use without abstinence was associated with lower relative VL (47%, 38%, respectively). CONCLUSIONS: Abstinence was associated with viral suppression. In addition, reducing use of illicit opioids or methamphetamine/crystal, even without abstinence, was also associated with viral suppression. Our findings highlight the impact of reducing substance use, even when abstinence is not achieved, and the potential benefits of medications, behavioral interventions, and harm-reduction interventions.


Assuntos
Infecções por HIV , Drogas Ilícitas , Transtornos Relacionados ao Uso de Substâncias , HIV , Infecções por HIV/prevenção & controle , Humanos , Estudos Longitudinais , Transtornos Relacionados ao Uso de Substâncias/complicações , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Carga Viral
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