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1.
Phys Rev Lett ; 132(25): 256701, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38996263

RESUMO

Converting angular momentum between different degrees of freedom within a magnetic material results from a dynamic interplay between electrons, magnons, and phonons. This interplay is pivotal to implementing spintronic device concepts that rely on spin angular momentum transport. We establish a new concept for long-range angular momentum transport that further allows us to address and isolate the magnonic contribution to angular momentum transport in a nanostructured metallic ferromagnet. To this end, we electrically excite and detect spin transport between two parallel and electrically insulated ferromagnetic metal strips on top of a diamagnetic substrate. Charge-to-spin current conversion within the ferromagnetic strip generates electronic spin angular momentum that is transferred to magnons via electron-magnon coupling. We observe a finite angular momentum flow to the second ferromagnetic strip across a diamagnetic substrate over micron distances, which is electrically detected in the second strip by the inverse charge-to-spin current conversion process. We discuss phononic and dipolar interactions as the likely cause to transfer angular momentum between the two strips. Moreover, our Letter provides the experimental basis to separate the electronic and magnonic spin transport and thereby paves the way towards magnonic device concepts that do not rely on magnetic insulators.

2.
Phytochem Anal ; 2024 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-39034429

RESUMO

INTRODUCTION: Untargeted metabolomics is a powerful tool that provides strategies for gaining a systematic understanding of quantitative changes in the levels of metabolites, especially when combining different metabolomic platforms. Vanilla is one of the world's most popular flavors originating from cured pods of the orchid Vanilla planifolia. However, only a few studies have investigated the metabolome of V. planifolia, and no LC-MS or GC-MS metabolomics studies with respect to leaves have been performed. OBJECTIVE: The aim of the study was to comprehensively characterize the metabolome of different organs (leaves, internodes, and aerial roots) of V. planifolia. MATERIAL AND METHODS: Characterization of the metabolome was achieved using two complementary platforms (GC × GC-MS, LC-QToF-MS), and metabolite identification was based on a comparison with in-house databases or curated external spectral libraries. RESULTS: In total, 127 metabolites could be identified with high certainty (confidence level 1 or 2) including sugars, amino acids, fatty acids, organic acids, and amines/amides but also secondary metabolites such as vanillin-related metabolites, flavonoids, and terpenoids. Ninty-eight metabolites showed significantly different intensities between the plant organs. Most strikingly, aglycons of flavonoids and vanillin-related metabolites were elevated in aerial roots, whereas its O-glycoside forms tended to be higher in leaves and/or internodes. This suggests that the more bioactive aglycones may accumulate where preferably needed, e.g. for defense against pathogens. CONCLUSION: The results derived from the study substantially expand the knowledge regarding the vanilla metabolome forming a valuable basis for more targeted investigations in future studies, e.g. towards an optimization of vanilla plant cultivation.

3.
Nat Commun ; 15(1): 4961, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38862514

RESUMO

Phases with spontaneous time-reversal ( T ) symmetry breaking are sought after for their anomalous physical properties, low-dissipation electronic and spin responses, and information-technology applications. Recently predicted altermagnetic phase features an unconventional and attractive combination of a strong T -symmetry breaking in the electronic structure and a zero or only weak-relativistic magnetization. In this work, we experimentally observe the anomalous Hall effect, a prominent representative of the T -symmetry breaking responses, in the absence of an external magnetic field in epitaxial thin-film Mn5Si3 with a vanishingly small net magnetic moment. By symmetry analysis and first-principles calculations we demonstrate that the unconventional d-wave altermagnetic phase is consistent with the experimental structural and magnetic characterization of the Mn5Si3 epilayers, and that the theoretical anomalous Hall conductivity generated by the phase is sizable, in agreement with experiment. An analogy with unconventional d-wave superconductivity suggests that our identification of a candidate of unconventional d-wave altermagnetism points towards a new chapter of research and applications of magnetic phases.

4.
Environ Res ; 257: 119238, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-38815717

RESUMO

BACKGROUND: Despite plausible behavioral and physiological pathways, limited evidence exists on how daily temperature variability is associated with acute mental health-related episodes. OBJECTIVES: We aimed to explore associations between daily temperature range (DTR) and mental health-related hospital visits using data of all hospital records in New York State during 1995-2014. We further examined factors that may modify these associations, including age, sex, hospital visit type and season. METHODS: Using a case-crossover design with distributed lag non-linear DTR terms (0-6 days), we estimated associations between ZIP Code-level DTR and hospital visits for mood (4.6 million hospital visits), anxiety (2.4 million), adjustment (∼368,000), and schizophrenia disorders (∼211,000), controlling for daily mean temperature, via conditional logistic regression models. We assessed potential heterogeneity by age, sex, hospital visit type (in-patient vs. out-patient), and season (summer, winter, and transition seasons). RESULTS: For all included outcomes, we observed positive associations from period minimum DTR (0.1 °C) until 25th percentile (5.2 °C) and between mean DTR (7.7 °C) and 90th percentile (12.2 °C), beyond which we observed negative associations. For mood disorders, an increase in DTR from 0.1 °C to 12.2 °C was associated with a cumulative 16.0% increase (95% confidence interval [CI]: 12.8, 19.2%) in hospital visit rates. This increase was highest during transition seasons (32.5%; 95%CI: 26.4, 39.0%) compared with summer (10.7%; 95%CI: 4.8, 16.8%) and winter (-1.6%; 95%CI: -7.6, 4.7%). For adjustment and schizophrenia disorders, the strongest associations were seen among the youngest group (0-24 years) with almost no association in the oldest group (65+ years). We observed no evidence for modification by sex and hospital visit type. DISCUSSION: Daily temperature variability was positively associated with mental health-related hospital visits within specific DTR ranges in New York State, after controlling for daily mean temperature. Given uncertainty on how climate change modifies temperature variability, additional research is crucial to comprehend the implications of these findings, particularly under different scenarios of future temperature variability.


Assuntos
Temperatura , New York , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , Idoso , Adulto Jovem , Adolescente , Estações do Ano , Transtornos Mentais/epidemiologia , Hospitalização/estatística & dados numéricos , Estudos Cross-Over , Saúde Mental/estatística & dados numéricos , Esquizofrenia/epidemiologia , Criança , Pré-Escolar
5.
Sci Adv ; 10(18): eadm8680, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38701214

RESUMO

Gas and propane stoves emit nitrogen dioxide (NO2) pollution indoors, but the exposures of different U.S. demographic groups are unknown. We estimate NO2 exposure and health consequences using emissions and concentration measurements from >100 homes, a room-specific indoor air quality model, epidemiological risk parameters, and statistical sampling of housing characteristics and occupant behavior. Gas and propane stoves increase long-term NO2 exposure 4.0 parts per billion volume on average across the United States, 75% of the World Health Organization's exposure guideline. This increased exposure likely causes ~50,000 cases of current pediatric asthma from long-term NO2 exposure alone. Short-term NO2 exposure from typical gas stove use frequently exceeds both World Health Organization and U.S. Environmental Protection Agency benchmarks. People living in residences <800 ft2 in size incur four times more long-term NO2 exposure than people in residences >3000 ft2 in size; American Indian/Alaska Native and Black and Hispanic/Latino households incur 60 and 20% more NO2 exposure, respectively, than the national average.


Assuntos
Poluição do Ar em Ambientes Fechados , Dióxido de Nitrogênio , Propano , Dióxido de Nitrogênio/análise , Humanos , Estados Unidos , Poluição do Ar em Ambientes Fechados/análise , Poluição do Ar em Ambientes Fechados/efeitos adversos , Exposição Ambiental/efeitos adversos , Habitação , Culinária , Poluentes Atmosféricos/análise
6.
J Am Board Fam Med ; 37(2): 290-294, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38740467

RESUMO

BACKGROUND: The COVID-19 pandemic disrupted how primary care patients with chronic pain received care. Our study sought to understand how long-term opioid therapy (LtOT) for chronic pain changed over the course of the pandemic overall and for different demographic subgroups. METHODS: We used data from electronic health records of 64 primary care clinics across Washington state and Idaho to identify patients who had a chronic pain diagnosis and were receiving long-term opioid therapy. We defined 10-month periods in 2019 to 2021 as prepandemic, early pandemic and late pandemic and used generalized estimating equations analysis to compare across these time periods and demographic characteristics. RESULTS: We found a proportional decrease in LtOT for chronic pain in the early months of the pandemic (OR = 0.94, P = .007) followed by an increase late pandemic (OR = 1.08, P = .002). Comparing late pandemic to prepandemic, identifying as Asian or Black, having fewer comorbidities, or living in an urban area were associated with higher likelihood of being prescribed LtOT. DISCUSSION: The use of LtOT for chronic pain in primary care has increased from before to after the COVID-19 pandemic with racial/ethnic and geographic disparities. Future research is needed to understand these disparities in LtOT and their effect on patient outcomes.


Assuntos
Analgésicos Opioides , COVID-19 , Dor Crônica , Disparidades em Assistência à Saúde , Atenção Primária à Saúde , Humanos , COVID-19/epidemiologia , Dor Crônica/tratamento farmacológico , Dor Crônica/epidemiologia , Masculino , Analgésicos Opioides/uso terapêutico , Feminino , Pessoa de Meia-Idade , Washington/epidemiologia , Disparidades em Assistência à Saúde/estatística & dados numéricos , Atenção Primária à Saúde/estatística & dados numéricos , Adulto , Idoso , Idaho/epidemiologia , SARS-CoV-2 , Pandemias
7.
J Acoust Soc Am ; 155(4): 2875-2890, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38682913

RESUMO

Numerical simulations of head-related transfer functions (HRTFs) conventionally assume a rigid boundary condition for the pinna. The human pinna, however, is an elastic deformable body that can vibrate due to incident acoustic waves. This work investigates how sound-induced vibrations of the pinna can affect simulated HRTF magnitudes. The work will motivate the research question by measuring the sound-induced vibrational patterns of an artificial pinna with a high-speed holographic interferometric system. Then, finite element simulations are used to determine HRTFs for a tabletop model of the B&K 5128 head and torso simulator for a number of directions. Two scenarios are explored: one where the pinna is modeled as perfectly rigid, and another where the pinna is modeled as linear elastic with material properties close to that of auricular cartilage. The findings suggest that pinna vibrations have negligible effects on HRTF magnitudes up to 5 kHz. The same conclusion, albeit with less certainty, is drawn for higher frequencies. Finally, the importance of the elastic domain's material properties is emphasized and possible implications for validation studies on dummy heads 1as well as the limitations of the present work are discussed in detail.


Assuntos
Simulação por Computador , Pavilhão Auricular , Análise de Elementos Finitos , Cabeça , Som , Vibração , Humanos , Pavilhão Auricular/fisiologia , Pavilhão Auricular/anatomia & histologia , Cabeça/fisiologia , Cabeça/anatomia & histologia , Holografia/métodos , Interferometria/métodos , Elasticidade , Análise Numérica Assistida por Computador , Modelos Biológicos , Movimento (Física) , Estimulação Acústica
8.
Gesundheitswesen ; 86(4): 263-273, 2024 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-38579731

RESUMO

BACKGROUND: Memory clinics can contribute significantly to a qualified diagnosis of dementia. Since the accessibility of medical facilities is an important predictor for their utilisation, the aim of this study was to determine the accessibility of memory clinics for persons with dementia in Bavaria. METHODS: We used a Geographic Information System (GIS) to determine travel times to the nearest memory clinic for all Bavarian municipalities based on OpenStreetMap road network data. RESULTS: The majority of the modelled persons with dementia in Bavaria (40%; n = 93,950) live in communities with an average travel time of 20 to 40 minutes to the nearest memory clinic. Almost 7,000 (3%) require more than one hour. Especially persons from rural communities have to travel significantly longer distances than people from urban areas. CONCLUSION: In view of demographic developments, there is an urgent need for memory clinics to be accessible throughout the country for all persons with dementia, regardless of where they live. The systematic development of memory clinics in areas with long travel times or the establishment of mobile diagnostic services could help to improve dementia care.


Assuntos
Demência , Viagem , Humanos , Alemanha/epidemiologia , Sistemas de Informação Geográfica , Instituições de Assistência Ambulatorial , Acessibilidade aos Serviços de Saúde , Demência/diagnóstico , Demência/epidemiologia
9.
Artigo em Alemão | MEDLINE | ID: mdl-38656540

RESUMO

Paraneoplastic pemphigus is a rare, life-threatening autoimmune disease that is clinically characterized by mostly extensive and refractory mucosal erosions and polymorphous skin lesions. We report here on a 16-year-old girl with isolated oral erosions, in whom mucosal pemphigoid was initially suspected and after treatment with prednisolone and dapsone marked improvement was achieved. However, a few months later the patient developed massive respiratory insufficiency as a result of bronchiolitis obliterans, so that a lung transplant was planned. As part of the preparatory diagnostic workup, unicentric, abdominally localized Castleman's disease was diagnosed, which ultimately led to the diagnosis of paraneoplastic pemphigus as evidenced by envoplakin autoantibodies. Tumor resection and subsequent lung transplantation achieved good results with sustained mucocutaneous remission.

10.
Ann Fam Med ; 22(3): 244-246, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38429105

RESUMO

The United States is facing a social isolation and loneliness crisis. In response, the US Surgeon General issued an advisory in May 2023 recommending actions that health care, community programs, and social services can take to collaboratively improve social connection. Primary care has a critical role to play in implementing the Surgeon General's recommendations. We present social isolation and loneliness as medical issues and highlight next steps for the primary care sector to combat this epidemic.Annals Early Access article.


Assuntos
Solidão , Atenção Primária à Saúde , Isolamento Social , Humanos , Solidão/psicologia , Isolamento Social/psicologia , Estados Unidos , COVID-19/psicologia , COVID-19/epidemiologia , Epidemias
11.
Glob Chang Biol ; 30(3): e17225, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38462708

RESUMO

It is well known that biodiversity positively affects ecosystem functioning, leading to enhanced ecosystem stability. However, this knowledge is mainly based on analyses using single ecosystem functions, while studies focusing on the stability of ecosystem multifunctionality (EMF) are rare. Taking advantage of a long-term grassland biodiversity experiment, we studied the effect of plant diversity (1-60 species) on EMF over 5 years, its temporal stability, as well as multifunctional resistance and resilience to a 2-year drought event. Using split-plot treatments, we further tested whether a shared history of plants and soil influences the studied relationships. We calculated EMF based on functions related to plants and higher-trophic levels. Plant diversity enhanced EMF in all studied years, and this effect strengthened over the study period. Moreover, plant diversity increased the temporal stability of EMF and fostered resistance to reoccurring drought events. Old plant communities with shared plant and soil history showed a stronger plant diversity-multifunctionality relationship and higher temporal stability of EMF than younger communities without shared histories. Our results highlight the importance of old and biodiverse plant communities for EMF and its stability to extreme climate events in a world increasingly threatened by global change.


Assuntos
Ecossistema , Pradaria , Biodiversidade , Plantas , Solo
12.
Langmuir ; 40(8): 4350-4360, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38364791

RESUMO

Ceria nanomaterials with facile CeIII/IV redox behavior are used in sensing, catalytic, and therapeutic applications, where inclusion of CeIII has been correlated with reactivity. Understanding assembly pathways of CeO2 nanoparticles (NC-CeO2) in water has been challenged by "blind" synthesis, including rapid assembly/precipitation promoted by heat or strong base. Here, we identify a layered phase denoted Ce-I with a proposed formula CeIV(OH)3(NO3)·xH2O (x ≈ 2.5), obtained by adding electrolytes to aqueous cerium ammonium nitrate (CAN) to force precipitation. Ce-I represents intermediate hydrolysis species between dissolved CAN and NC-CeO2, where CAN is a commonly used CeIV compound that exhibits unusual aqueous and organic solubility. Ce-I features Ce-(OH)2-Ce units, representing the first step of hydrolysis toward NC-CeO2 formation, challenging prior assertions about CeIV hydrolysis. Structure/composition of poorly crystalline Ce-I was corroborated by a pair distribution function, Ce-L3 XAS (X-ray absorption spectroscopy), compositional analysis, and 17O nuclear magnetic resonance spectroscopy. Formation of Ce-I and its transformation to NC-CeO2 is documented in solution by small-angle X-ray scattering (SAXS) and in the solid-state by transmission electron microscopy (TEM) and powder X-ray diffraction. Morphologies identified by TEM support form factor models for SAXS analysis, evidencing the incipient assembly of Ce-I. Finally, two morphologies of NC-CeO2 are identified. Sequentially, spherical NC-CeO2 particles coexist with Ce-I, and asymmetric NC-CeO2 with up to 35% CeIII forms at the expense of Ce-I, suggesting direct replacement.

13.
Sci Adv ; 10(7): eadi7494, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38354235

RESUMO

Nanoparticle aggregates in solution controls surface reactivity and function. Complete dispersion often requires additive sorbents to impart a net repulsive interaction between particles. Facet engineering of nanocrystals offers an alternative approach to produce monodisperse suspensions simply based on facet-specific interaction with solvent molecules. Here, we measure the dispersion/aggregation of three morphologies of hematite (α-Fe2O3) nanoparticles in varied aqueous solutions using ex situ electron microscopy and in situ small-angle x-ray scattering. We demonstrate a unique tendency of (104) hematite nanoparticles to maintain a monodisperse state across a wide range of solution conditions not observed with (001)- and (116)-dominated particles. Density functional theory calculations reveal an inert, densely hydrogen-bonded first water layer on the (104) facet that favors interparticle dispersion. Results validate the notion that nanoparticle dispersions can be controlled through morphology for specific solvents, which may help in the development of various nanoparticle applications that rely on their interfacial area to be highly accessible in stable suspensions.

14.
ACS Nano ; 18(4): 3497-3508, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38215492

RESUMO

Two-dimensional (2D) materials have attracted intense interest due to their potential for applications in fields ranging from chemical sensing to catalysis, energy storage, and biomedicine. Recently, peptoids, a class of biomimetic sequence-defined polymers, have been found to self-assemble into 2D crystalline sheets that exhibit unusual properties, such as high chemical stability and the ability to self-repair. The structure of a peptoid is close to that of a peptide except that the side chains are appended to the amide nitrogen rather than the α carbon. In this study, we investigated the effect of peptoid sequence on the mechanism and kinetics of 2D assembly on mica surfaces using in situ AFM and time-resolved X-ray scattering. We explored three distinct peptoid sequences that are amphiphilic in nature with hydrophobic and hydrophilic blocks and are known to self-assemble into 2D sheets. The results show that their assembly on mica starts with deposition of aggregates that spread to establish 2D islands, which then grow by attachment of peptoids, either monomers or unresolvable small oligomers, following well-known laws of crystal step advancement. Extraction of the solubility and kinetic coefficient from the dependence of the growth rate on peptoid concentration reveals striking differences between the sequences. The sequence with the slowest growth rate in bulk and with the highest solubility shows almost no detachment; i.e., once a growth unit attaches to the island edge, there is almost no probability of detaching. Furthermore, a peptoid sequence with a hydrophobic tail conjugated to the final carboxyl residue in the hydrophilic block has enhanced hydrophobic interactions and exhibits rapid assembly both in the bulk and on mica. These assembly outcomes suggest that, while the π-π interactions between adjacent hydrophobic blocks play a major role in peptoid assembly, sequence details, particularly the location of charged groups, as well as interaction with the underlying substrate can significantly alter the thermodynamic stability and assembly kinetics.


Assuntos
Peptoides , Peptoides/química , Peptídeos/química , Silicatos de Alumínio , Amidas/química
15.
J Gen Intern Med ; 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38273069

RESUMO

BACKGROUND: There are no consistent data on US primary care clinicians and primary care practices owing to the lack of standard methods to identify them, hampering efforts in primary care improvement. METHODS: We develop a pragmatic framework that identifies primary care clinicians and practices in the context of the US healthcare system, and applied the framework to the IQVIA OneKey Healthcare Professional database to identify and profile primary care clinicians and practices in the USA. RESULTS: Our framework prescribes sequential steps to identify primary care clinicians by cross-examining clinician specialties and organizational affiliations, and then identify primary care practices based on organization types and presence of primary care clinicians. Applying this framework to the 2021 IQVIA data, we identified 365,751 physicians with a primary specialty in primary care, and after excluding those who further specialized (24%), served as hospitalists (5%), or worked in non-primary care settings (41%), we determined that 179,369 (49%) of them were actually practicing primary care. We identified 287,506 nurse practitioners and 134,083 physician assistants and determined that 88,574 (31%) and 29,781 (22%), respectively, were delivering primary care. We identified 94,489 primary care practices, and found that 45% of them were with one primary care physician, 15% had two physicians, 12% employed nurse practitioners or physician assistants only, and 19% employed both primary care physicians and specialists. CONCLUSIONS: Our approach offers a pragmatic and consistent alternative to the diverse methods currently used to identify and profile primary care workforce and organizations in the USA.

16.
Artigo em Inglês | MEDLINE | ID: mdl-38008877

RESUMO

The use of ß-lactam (BL) and ß-lactamase inhibitor (BLI) combinations, such as piperacillin-tazobactam (PIP-TAZ) is an effective strategy to combat infections by extended-spectrum ß-lactamase-producing bacteria. However, in Gram-negative bacteria, resistance (both mutational and adaptive) to BL-BLI combination can still develop through multiple mechanisms. These mechanisms may include increased ß-lactamase activity, reduced drug influx, and increased drug efflux. Understanding the relative contribution of these mechanisms during resistance development helps identify the most impactful mechanism to target in designing a treatment to counter BL-BLI resistance. This study used semi-mechanistic mathematical modeling in combination with antibiotic sensitivity assays to assess the potential impact of different resistance mechanisms during the development of PIP-TAZ resistance in a Klebsiella pneumoniae isolate expressing CTX-M-15 and SHV-1 ß-lactamases. The mathematical models were used to evaluate the potential impact of several cellular changes as a sole mediator of PIP-TAZ resistance. Our semi-mechanistic model identified 2 out of the 13 inspected mechanisms as key resistance mechanisms that may independently support the observed magnitude of PIP-TAZ resistance, namely porin loss and efflux pump up-regulation. Simulation using the resulting models also suggested the possible adjustment of PIP-TAZ dose outside its commonly used 8:1 dosing ratio. The current study demonstrated how theory-based mechanistic models informed by experimental data can be used to support hypothesis generation regarding potential resistance mechanisms, which may guide subsequent experimental studies.

17.
AJPM Focus ; 2(3): 100102, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37790667

RESUMO

Introduction: There were more than 100,000 fatal drug overdoses in the U.S. in 2021 alone. In recent years, there has been a shift in opioid mortality from predominantly White rural communities to Black urban communities. This study aimed to identify the Virginia communities disproportionately affected by the overdose crisis and to better understand the systemic factors contributing to disparities in opioid mortality. Methods: Using the state all-payer claims database, state mortality records, and census data, we created a multivariate model to examine the community-level factors contributing to racial disparities in opioid mortality. We used generalized linear mixed models to examine the associations between socioecologic factors and fatal opioid overdoses, opioid use disorder diagnoses, opioid-related emergency department visits, and mental health diagnoses. Results: Between 2015 and 2020, racial disparities in mortality widened. In 2020, Black males were 1.5 times more likely to die of an opioid overdose than White males (47.3 vs 31.6 per 100,000; p<0.001). The rate of mental health disorders strongly correlated with mortality (ß=0.53, p<0.001). Black individuals are not more likely to be diagnosed with opioid use disorder (ß=0.01, p=0.002) or with mental health disorders (ß= -0.12, p<0.001), despite higher fatal opioid overdoses. Conclusions: There are widening racial disparities in opioid mortality. Untreated mental health disorders are a major risk factor for opioid mortality. Findings show pathways to address inequities, including early linkage to care for mental health and opioid use disorders. This analysis shows the use of comprehensive socioecologic data to identify the precursors to fatal overdoses, which could allow earlier intervention and reallocation of resources in high-risk communities.

18.
J Neurosci ; 43(50): 8700-8722, 2023 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-37903594

RESUMO

Social communication is crucial for the survival of many species. In most vertebrates, a dedicated chemosensory system, the vomeronasal system (VNS), evolved to process ethologically relevant chemosensory cues. The first central processing stage of the VNS is the accessory olfactory bulb (AOB), which sends information to downstream brain regions via AOB mitral cells (AMCs). Recent studies provided important insights about the functional properties of AMCs, but little is known about the principles that govern their coordinated activity. Here, we recorded local field potentials (LFPs) and single-unit activity in the AOB of adult male and female mice during presentation of natural stimuli. Our recordings reveal prominent LFP theta-band oscillatory episodes with a characteristic spatial pattern across the AOB. Throughout an experiment, the AOB network shows varying degrees of similarity to this pattern, in a manner that depends on the sensory stimulus. Analysis of LFP signal polarity and single-unit activity indicates that oscillatory episodes are generated locally within the AOB, likely representing a reciprocal interaction between AMCs and granule cells. Notably, spike times of many AMCs are constrained to the negative LFP oscillation phase in a manner that can drastically affect integration by downstream processing stages. Based on these observations, we propose that LFP oscillations may gate, bind, and organize outgoing signals from individual AOB neurons to downstream processing stages. Our findings suggest that, as in other neuronal systems and brain regions, population-level oscillations play a key role in organizing and enhancing transmission of socially relevant chemosensory information.SIGNIFICANCE STATEMENT The accessory olfactory bulb (AOB) is the first central stage of the vomeronasal system, a chemosensory system dedicated to processing cues from other organisms. Information from the AOB is conveyed to other brain regions via activity of its principal neurons, AOB mitral cells (AMCs). Here, we show that socially relevant sensory stimulation of the mouse vomeronasal system leads not only to changes in AMC activity, but also to distinct theta-band (∼5 Hz) oscillatory episodes in the local field potential. Notably AMCs favor the negative phase of these oscillatory events. Our findings suggest a novel mechanism for the temporal coordination of distributed patterns of neuronal activity, which can serve to efficiently activate downstream processing stages.


Assuntos
Neurônios , Bulbo Olfatório , Camundongos , Masculino , Feminino , Animais , Bulbo Olfatório/fisiologia , Neurônios/fisiologia , Sinais (Psicologia)
19.
Sci Adv ; 9(43): eadi8986, 2023 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-37889970

RESUMO

Various cellular sources hamper interpretation of positron emission tomography (PET) biomarkers in the tumor microenvironment (TME). We developed an approach of immunomagnetic cell sorting after in vivo radiotracer injection (scRadiotracing) with three-dimensional (3D) histology to dissect the cellular allocation of PET signals in the TME. In mice with implanted glioblastoma, translocator protein (TSPO) radiotracer uptake per tumor cell was higher compared to tumor-associated microglia/macrophages (TAMs), validated by protein levels. Translation of in vitro scRadiotracing to patients with glioma immediately after tumor resection confirmed higher single-cell TSPO tracer uptake of tumor cells compared to immune cells. Across species, cellular radiotracer uptake explained the heterogeneity of individual TSPO-PET signals. In consideration of cellular tracer uptake and cell type abundance, tumor cells were the main contributor to TSPO enrichment in glioblastoma; however, proteomics identified potential PET targets highly specific for TAMs. Combining cellular tracer uptake measures with 3D histology facilitates precise allocation of PET signals and serves to validate emerging novel TAM-specific radioligands.


Assuntos
Glioblastoma , Glioma , Humanos , Camundongos , Animais , Glioblastoma/diagnóstico por imagem , Glioblastoma/metabolismo , Microambiente Tumoral , Glioma/patologia , Tomografia por Emissão de Pósitrons/métodos , Microglia/metabolismo , Proteínas de Transporte/metabolismo , Receptores de GABA/metabolismo
20.
Sci Rep ; 13(1): 14748, 2023 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-37679380

RESUMO

The microscopic mechanism of the light-matter interactions that induce orbital angular momentum (OAM) in electromagnetic fields is not thoroughly understood. In this work, we employ Archimedean spiral vortex generators in time-resolved numerical simulations using the Octopus code to observe the behind-the-scenes of OAM generation. We send a perfect circularly-polarized plane-wave light onto plasmonic optical vortex generators and observe the resulting twisted light formation with complete spatio-temporal information. In agreement with previous works, we find that emission from the plasmonic spiral branches shapes the vortex-like structure and governs the OAM generation in the outgoing electromagnetic field. To characterize the generated beam further, we emulate the emission from vortex generators with current emitters preserving the spiral geometry. We subject a point-particle system to the generated field and record the orbital angular momentum transfer between the electromagnetic field and the point particle. Finally, we probe the OAM density locally by studying the induced classical trajectory of point particles, which provides further insight into the spatio-temporal features of the induced OAM.

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