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1.
Molecules ; 29(13)2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38999002

RESUMO

We examine the optical and electronic properties of a GaAs spherical quantum dot with a hydrogenic impurity in its center. We study two different confining potentials: (1) a modified Gaussian potential and (2) a power-exponential potential. Using the finite difference method, we solve the radial Schrodinger equation for the 1s and 1p energy levels and their probability densities and subsequently compute the optical absorption coefficient (OAC) for each confining potential using Fermi's golden rule. We discuss the role of different physical quantities influencing the behavior of the OAC, such as the structural parameters of each potential, the dipole matrix elements, and their energy separation. Our results show that modification of the structural physical parameters of each potential can enable new optoelectronic devices that can leverage inter-sub-band optical transitions.

2.
Nutrients ; 16(13)2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38999785

RESUMO

Excessive vitamin A (VA) negatively impacts bone. Interactions between VA and vitamin D (VD) in bone health are not well-understood. This study used a traditional two-by-two factorial design. Pigs were weaned and randomized to four treatments (n = 13/group): -A-D, -A+D, +A-D, and +A+D for 3 and 5 wk. Serum, liver, kidney, adrenal glands, spleen, and lung were analyzed by ultra-performance LC. Growth was evaluated by weight measured weekly and BMD by DXA. Weights were higher in -A+D (18.1 ± 1.0 kg) and +A+D (18.2 ± 2.3 kg) at 5 wk than in -A-D (15.5 ± 2.1 kg) and +A-D (15.8 ± 1.5 kg). Serum retinol concentrations were 0.25 ± 0.023, 0.22 ± 0.10, 0.77 ± 0.12, and 0.84 ± 0.28 µmol/L; and liver VA concentrations were 0.016 ± 0.015, 0.0065 ± 0.0035, 2.97 ± 0.43, 3.05 ± 0.68 µmol/g in -A-D, -A+D, +A-D, and +A+D, respectively. Serum 25(OH)D3 concentrations were 1.5 ± 1.11, 1.8 ± 0.43, 27.7 ± 8.91, and 23.9 ± 6.67 ng/mL in -A-D, +A-D, -A+D, +A+D, respectively, indicating a deficiency in -D and adequacy in +D. BMD was highest in +D (p < 0.001). VA and the interaction had no effect on BMD. Dietary VD influenced weight gain, BMD, and health despite VA status.


Assuntos
Densidade Óssea , Deficiência de Vitamina A , Vitamina A , Vitamina D , Animais , Densidade Óssea/efeitos dos fármacos , Vitamina D/sangue , Suínos , Vitamina A/sangue , Feminino , Masculino , Modelos Animais de Doenças , Fígado/metabolismo , Fígado/efeitos dos fármacos , Suplementos Nutricionais
3.
Anat Sci Educ ; 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38961266

RESUMO

Undergraduate introductory human anatomy and human physiology courses are either taught as discipline-specific or integrated anatomy and physiology (A&P) sequences. An institution underwent a curricular revision to change the course approach from discipline-specific Human Anatomy and Human Physiology to an integrated A&P I and II sequence, allowing the unique opportunity to explore the potential role of contextual learning in academic achievement and content retention. Mediation and moderation analysis was used to evaluate lecture examinations, laboratory practical examinations, and anatomical content retention between the different course approaches. Undergraduate students in the integrated A&P I course approach performed significantly better on lecture assessments and had a higher anatomy content retention rate at the end of the year than students enrolled in the standalone Human Anatomy course. The lecture examination averages between Human Physiology and A&P II (the second course in the sequence), as well as the anatomy laboratory practical examinations, were not significantly different between discipline-specific and integrated course approaches. The results suggest contextual learning-providing physiological context to anatomical structures-increases the anatomical content retention and academic achievement overall.

4.
JMIR Mhealth Uhealth ; 12: e55094, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39018100

RESUMO

BACKGROUND: Personal sensing, leveraging data passively and near-continuously collected with wearables from patients in their ecological environment, is a promising paradigm to monitor mood disorders (MDs), a major determinant of the worldwide disease burden. However, collecting and annotating wearable data is resource intensive. Studies of this kind can thus typically afford to recruit only a few dozen patients. This constitutes one of the major obstacles to applying modern supervised machine learning techniques to MD detection. OBJECTIVE: In this paper, we overcame this data bottleneck and advanced the detection of acute MD episodes from wearables' data on the back of recent advances in self-supervised learning (SSL). This approach leverages unlabeled data to learn representations during pretraining, subsequently exploited for a supervised task. METHODS: We collected open access data sets recording with the Empatica E4 wristband spanning different, unrelated to MD monitoring, personal sensing tasks-from emotion recognition in Super Mario players to stress detection in undergraduates-and devised a preprocessing pipeline performing on-/off-body detection, sleep/wake detection, segmentation, and (optionally) feature extraction. With 161 E4-recorded subjects, we introduced E4SelfLearning, the largest-to-date open access collection, and its preprocessing pipeline. We developed a novel E4-tailored transformer (E4mer) architecture, serving as the blueprint for both SSL and fully supervised learning; we assessed whether and under which conditions self-supervised pretraining led to an improvement over fully supervised baselines (ie, the fully supervised E4mer and pre-deep learning algorithms) in detecting acute MD episodes from recording segments taken in 64 (n=32, 50%, acute, n=32, 50%, stable) patients. RESULTS: SSL significantly outperformed fully supervised pipelines using either our novel E4mer or extreme gradient boosting (XGBoost): n=3353 (81.23%) against n=3110 (75.35%; E4mer) and n=2973 (72.02%; XGBoost) correctly classified recording segments from a total of 4128 segments. SSL performance was strongly associated with the specific surrogate task used for pretraining, as well as with unlabeled data availability. CONCLUSIONS: We showed that SSL, a paradigm where a model is pretrained on unlabeled data with no need for human annotations before deployment on the supervised target task of interest, helps overcome the annotation bottleneck; the choice of the pretraining surrogate task and the size of unlabeled data for pretraining are key determinants of SSL success. We introduced E4mer, which can be used for SSL, and shared the E4SelfLearning collection, along with its preprocessing pipeline, which can foster and expedite future research into SSL for personal sensing.


Assuntos
Transtornos do Humor , Aprendizado de Máquina Supervisionado , Dispositivos Eletrônicos Vestíveis , Humanos , Estudos Prospectivos , Dispositivos Eletrônicos Vestíveis/estatística & dados numéricos , Dispositivos Eletrônicos Vestíveis/normas , Masculino , Feminino , Transtornos do Humor/diagnóstico , Transtornos do Humor/psicologia , Adulto , Exercício Físico/psicologia , Exercício Físico/fisiologia , Universidades/estatística & dados numéricos , Universidades/organização & administração
5.
Hepatol Commun ; 8(8)2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39023332

RESUMO

BACKGROUND: The epigenome, the set of modifications to DNA and associated molecules that control gene expression, cellular identity, and function, plays a major role in mediating cellular responses to outside factors. Thus, evaluation of the epigenetic state can provide insights into cellular adaptions occurring over the course of disease. METHODS: We performed epigenome-wide association studies of primary sclerosing cholangitis (PSC) and primary biliary cholangitis (PBC) using the Illumina MethylationEPIC Bead Chip. RESULTS: We found evidence of increased epigenetic age acceleration and differences in predicted immune cell composition in patients with PSC and PBC. Epigenetic profiles demonstrated differences in predicted protein levels including increased levels of tumor necrosis factor receptor superfamily member 1B in patients with cirrhotic compared to noncirrhotic PSC and PBC. Epigenome-wide association studies of PSC discovered strongly associated 5'-C-phosphate-G-3' sites in genes including vacuole membrane protein 1 and SOCS3, and epigenome-wide association studies of PBC found strong 5'-C-phosphate-G-3' associations in genes including NOD-like receptor family CARD domain containing 5, human leukocyte antigen-E, and PSMB8. Analyses identified disease-associated canonical pathways and upstream regulators involved with immune signaling and activation of macrophages and T-cells. A comparison of PSC and PBC data found relatively little overlap at the 5'-C-phosphate-G-3' and gene levels with slightly more overlap at the level of pathways and upstream regulators. CONCLUSIONS: This study provides insights into methylation profiles of patients that support current concepts of disease mechanisms and provide novel data to inspire future research. Studies to corroborate our findings and expand into other -omics layers will be invaluable to further our understanding of these rare diseases with the goal to improve and individualize prognosis and treatment.


Assuntos
Colangite Esclerosante , Metilação de DNA , Epigênese Genética , Estudo de Associação Genômica Ampla , Cirrose Hepática Biliar , Humanos , Colangite Esclerosante/genética , Colangite Esclerosante/imunologia , Cirrose Hepática Biliar/genética , Cirrose Hepática Biliar/imunologia , Feminino , Pessoa de Meia-Idade , Masculino , Adulto , Epigenoma , Epigenômica , Idoso
6.
J Opt Soc Am A Opt Image Sci Vis ; 41(5): 892-905, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38856576

RESUMO

In this three-part paper series, we develop a method to trace the lines of flux through a three-dimensional wavefield by following a direction that is governed by the derivative of the phase at each point, a process that is best described as flux tracing but which we interchangeably name "nonlinear ray tracing." In this first part, we provide a tutorial on the high-speed calculation of three-dimensional complex wavefields, which is a necessary precursor to flux tracing. The basis of this calculation is the angular spectrum method, a well-known numerical algorithm that can be used to efficiently and accurately calculate diffracted fields for numerical apertures <0.7. It is known that this approach yields identical predictions to the first Rayleigh-Sommerfeld solution. We employ the angular spectrum method to develop two algorithms that generate the 3D complex wavefield in the region of focus of a lens. The first algorithm is based on the thin lens approximation, and the second is based on the concept of an ideal lens, which can be modeled using an optical Fourier transform. We review how these algorithms can be used to calculate focused laser beams with T E M 00 and T E M 01 laser profiles. The three-dimensional sampling requirements of the focused field are explained in detail, and expressions for the computational and memory efficiency of the two algorithms are developed. These two algorithms generate the 3D scaffold for the flux tracing method developed in the second paper, and in the third paper we highlight the application of the method to understanding monochromatic lens aberration. Disregarding the second and third papers, this first paper will serve as a practical tutorial for anyone seeking to compute focused fields in three dimensions.

7.
J Opt Soc Am A Opt Image Sci Vis ; 41(5): 906-919, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38856577

RESUMO

In this three-part paper series, we develop a method to trace the lines of flux through a three-dimensional wavefield by following a direction that is governed by the derivative of the phase at each point, a process that is best described as flux tracing but which we interchangeably name "nonlinear ray tracing." In the first part we focused on the high-speed calculation of focused three-dimensional complex wavefields in the paraxial approximation for T E M 00 and T E M 01 laser modes. The algorithms developed in the first paper are first used to generate the three-dimensional grid of samples of the complex wavefield in the focal region. In this second part, we focus on tracing a flux through this three-dimensional point cloud. For a given "ray" at an arbitrary position in the 3D volume, interpolation of the three-dimensional samples is applied to determine the derivative of the phase (normal to the direction of propagation) at the ray position, which is then used to direct the ray as it "propagates" forward in a straight line over a short distance to a subsequent plane; the process is repeated between consecutive planes. The initial origin of the ray can be chosen arbitrarily at any point, and the ray can then be traced through the volume with appropriate interpolation. Results are demonstrated for focused wavefields in the absence of aberrations, corresponding to the cases highlighted in the first paper. Some of the most interesting results relate to focused Laguerre-Gaussian beams, for which the rays are found to spiral at different rates of curvature. In the third paper we extend the application of this algorithm to the investigation of lens aberration.

8.
J Opt Soc Am A Opt Image Sci Vis ; 41(5): 920-931, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38856578

RESUMO

Using the flux tracing algorithm developed in the previous two parts, we examine the nonlinear rays that pass through the focus of a lens containing monochromatic aberrations. Lens aberration is modeled differently in the numerical propagation algorithms relating to the thin lens and the ideal lens cases. For the former, an additive phase term is applied to the transmission function of the thin lens, which describes a distortion in the thickness function of the lens, and for the latter an additive phase term is added to the pupil function of the lens (the Fourier transform of the image plane). In both cases, the Zernike polynomials are applied to model various aberrations including spherical, defocus, comatic, astigmatism, trefoil, and quadrafoil. Despite the different methods of modeling aberration for the two types of lenses, remarkably similar results are obtained for both cases. A discussion is also provided on the relationship between classical wavefront aberration theory and nonlinear tracing. This paper demonstrates the extraordinary potential of nonlinear ray tracing to gain insights into complex optical phenomena.

9.
Cancer Cell ; 42(7): 1202-1216.e8, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38906155

RESUMO

Tumor-specific CD8+ T cells are frequently dysfunctional and unable to halt tumor growth. We investigated whether tumor-specific CD4+ T cells can be enlisted to overcome CD8+ T cell dysfunction within tumors. We find that the spatial positioning and interactions of CD8+ and CD4+ T cells, but not their numbers, dictate anti-tumor responses in the context of adoptive T cell therapy as well as immune checkpoint blockade (ICB): CD4+ T cells must engage with CD8+ T cells on the same dendritic cell during the effector phase, forming a three-cell-type cluster (triad) to license CD8+ T cell cytotoxicity and cancer cell elimination. When intratumoral triad formation is disrupted, tumors progress despite equal numbers of tumor-specific CD8+ and CD4+ T cells. In patients with pleural mesothelioma treated with ICB, triads are associated with clinical responses. Thus, CD4+ T cells and triads are required for CD8+ T cell cytotoxicity during the effector phase and tumor elimination.


Assuntos
Linfócitos T CD4-Positivos , Linfócitos T CD8-Positivos , Humanos , Linfócitos T CD8-Positivos/imunologia , Animais , Linfócitos T CD4-Positivos/imunologia , Camundongos , Imunoterapia/métodos , Neoplasias/imunologia , Neoplasias/terapia , Inibidores de Checkpoint Imunológico/uso terapêutico , Inibidores de Checkpoint Imunológico/farmacologia , Camundongos Endogâmicos C57BL , Imunoterapia Adotiva/métodos , Células Dendríticas/imunologia , Linhagem Celular Tumoral , Microambiente Tumoral/imunologia
10.
J Neurosci ; 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38937102

RESUMO

Neocortex and striatum are topographically organized for sensory and motor functions. While sensory and motor areas are lateralized for touch and motor control, respectively, frontal areas are involved in decision making, where lateralization of function may be less important. This study contrasted the topographic precision of cell type-specific ipsilateral and contralateral cortical projections while varying the injection site location in transgenic mice of both sexes. While sensory cortical areas had strongly topographic outputs to ipsilateral cortex and striatum, they were weaker and not as topographically precise to contralateral targets. Motor cortex had somewhat stronger projections, but still relatively weak contralateral topography. In contrast, frontal cortical areas had high degrees of topographic similarity for both ipsilateral and contralateral projections to cortex and striatum. Corticothalamic organization is mainly ipsilateral, with weaker, more medial contralateral projections. Corticostriatal computations might integrate input outside closed basal ganglia loops using contralateral projections, enabling the two hemispheres to act as a unit to converge on one result in motor planning and decision making.Significance Statement Each cerebral hemisphere is responsible for sensation and movement of the opposite side of the body. Many axonal projections cross the midline to target contralateral areas. Crossed corticocortical, corticostriatal, and corticothalamic projections originate from much of neocortex, but how these projections vary across cortical regions and cell types is unknown. We quantify differences in the strength and targeting of ipsilateral and contralateral projections from frontal, motor, and somatosensory areas. The contralateral corticocortical and corticostriatal projections are proposed to play a larger role in frontal areas than in sensory or motor ones as a circuit basis for unifying computation across hemispheres in motor planning, while contralateral connectivity plays a smaller role in sensory and motor processing.

11.
Sci Rep ; 14(1): 14446, 2024 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-38910176

RESUMO

Coyotes (Canis latrans) are believed to contribute to declining kit fox (Vulpes macrotis) numbers in the Great Basin desert through intraguild predation. Intraguild prey have been shown to exhibit adaptive compromise, whereby an animal increases selection for risky, but food-rich areas during times of food stress (i.e. winter). We evaluated the habitat selection of kit foxes in the Great Basin desert to elucidate if they demonstrated adaptive compromise as a method of coexisting with coyotes. We created 2nd order resource selection functions to analyze kit fox habitat selection associated with coyote relative probability of use (RPU), prey abundance, and type of soil substrate. In the summer, we found that kit fox selection for areas of relatively more abundant prey was not significant, and there was a small positive selection for coyote RPU. In the winter, we found a positive relationship between kit fox selection and prey abundance as well as a stronger selection for coyote RPU. These findings do follow the pattern of adaptive compromise. We also found kit foxes selected for silty and sandy soils, which are conducive to den construction, as they use dens seasonally for breeding but also year-round for multiple uses, including refugia from predators and extreme heat. Soil substrate appeared to be an important factor impacting kit fox habitat selection.


Assuntos
Coiotes , Clima Desértico , Ecossistema , Raposas , Comportamento Predatório , Estações do Ano , Animais , Raposas/fisiologia , Coiotes/fisiologia , Comportamento Predatório/fisiologia , Solo
12.
Clin Cancer Res ; 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38922360

RESUMO

BACKGROUND: Nonsurgical treatment options are increasingly needed for endometrial atypical hyperplasia (AH) and endometrioid endometrial cancer (EEC). Despite promising initial response rates, prospective long-term data and determinants for relapse are limited. METHODS: Follow-up data from patients in our prospective phase II trial of LIUD for AH/G1EEC were collected from medical records. Spatial transcriptomics (Nanostring GeoMX digital spatial profiling) with in silico cell type deconvolution and pathway analyses were employed on longitudinal biopsy samples from five patients across pre-treatment, on-treatment, and relapse. RESULTS: Of 43 participants exhibiting initial response to LIUD, 41 had follow-up data. Sixteen (39%) experienced relapse. Clinical factors associated with shorter response duration included younger age, initial diagnosis of G1EEC, lack of response at six months, premenopausal status, and Hispanic ethnicity (p<0.05), but only six-month response status remained a significant predictor in a multivariate model (p=0.023). LIUD increased abundance of NK cells (DMCP-counter score=46.13, FDR=0.004) and cytotoxic lymphocytes (DMCP-counter score=277.67, FDR=0.004), as well as lymphocyte cytotoxicity markers PRF1 (log2FC=1.62, FDR=0.025) and GZMA (log2FC=2.47, FDR=0.008). NK cells were reduced at relapse (DMCP-counter score=-55.96, FDR=0.02). Immune-related pathways (IFNα-response and TGFß-signaling) were enriched at relapse (FDR<0.05). IDO1 expression, reflecting immune exhaustion, was upregulated at relapse (FDR<0.05). CONCLUSIONS: Upfront resistance and relapse after initial response to LIUD for AH/G1EEC impacts nearly half of patients, remaining a major hurdle for non-surgical treatment of AH/G1EEC. Molecular studies evaluating longitudinal biopsies from a small cohort implicate immune mechanisms at relapse, including reversal of progestin-related immunomodulation and increased immune exhaustion.

13.
J Chem Inf Model ; 64(13): 5262-5272, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38869471

RESUMO

Venezuelan equine encephalitis virus (VEEV) is a highly virulent pathogen whose nuclear localization signal (NLS) sequence from capsid protein binds to the host importin-α transport protein and blocks nuclear import. We studied the molecular mechanisms by which two small ligands, termed I1 and I2, interfere with the binding of VEEV's NLS peptide to importin-α protein. To this end, we performed all-atom replica exchange molecular dynamics simulations probing the competitive binding of the VEEV coreNLS peptide and I1 or I2 ligand to the importin-α major NLS binding site. As a reference, we used our previous simulations, which examined noncompetitive binding of the coreNLS peptide or the inhibitors to importin-α. We found that both inhibitors completely abrogate the native binding of the coreNLS peptide, forcing it to adopt a manifold of nonnative loosely bound poses within the importin-α major NLS binding site. Both inhibitors primarily destabilize the native coreNLS binding by masking its amino acids rather than competing with it for binding to importin-α. Because I2, in contrast to I1, binds off-site localizing on the edge of the major NLS binding site, it inhibits fewer coreNLS native binding interactions than I1. Structural analysis is supported by computations of the free energies of the coreNLS peptide binding to importin-α with or without competition from the inhibitors. Specifically, both inhibitors reduce the free energy gain from coreNLS binding, with I1 causing significantly larger loss than I2. To test our simulations, we performed AlphaScreen experiments measuring IC50 values for both inhibitors. Consistent with in silico results, the IC50 value for I1 was found to be lower than that for I2. We hypothesize that the inhibitory action of I1 and I2 ligands might be specific to the NLS from VEEV's capsid protein.


Assuntos
Ligação Competitiva , Simulação de Dinâmica Molecular , Sinais de Localização Nuclear , alfa Carioferinas , alfa Carioferinas/metabolismo , alfa Carioferinas/química , alfa Carioferinas/antagonistas & inibidores , Ligantes , Sinais de Localização Nuclear/química , Vírus da Encefalite Equina Venezuelana/metabolismo , Vírus da Encefalite Equina Venezuelana/química , Ligação Proteica , Peptídeos/química , Peptídeos/metabolismo , Peptídeos/farmacologia , Sequência de Aminoácidos
14.
Acta Psychiatr Scand ; 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38890010

RESUMO

BACKGROUND: Affective states influence the sympathetic nervous system, inducing variations in electrodermal activity (EDA), however, EDA association with bipolar disorder (BD) remains uncertain in real-world settings due to confounders like physical activity and temperature. We analysed EDA separately during sleep and wakefulness due to varying confounders and potential differences in mood state discrimination capacities. METHODS: We monitored EDA from 102 participants with BD including 35 manic, 29 depressive, 38 euthymic patients, and 38 healthy controls (HC), for 48 h. Fifteen EDA features were inferred by mixed-effect models for repeated measures considering sleep state, group and covariates. RESULTS: Thirteen EDA feature models were significantly influenced by sleep state, notably including phasic peaks (p < 0.001). During wakefulness, phasic peaks showed different values for mania (M [SD] = 6.49 [5.74, 7.23]), euthymia (5.89 [4.83, 6.94]), HC (3.04 [1.65, 4.42]), and depression (3.00 [2.07, 3.92]). Four phasic features during wakefulness better discriminated between HC and mania or euthymia, and between depression and euthymia or mania, compared to sleep. Mixed symptoms, average skin temperature, and anticholinergic medication affected the models, while sex and age did not. CONCLUSION: EDA measured from awake recordings better distinguished between BD states than sleep recordings, when controlled by confounders.

15.
bioRxiv ; 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38854096

RESUMO

The cardinal symptoms of Parkinson's disease (PD) such as bradykinesia and akinesia are debilitating, and treatment options remain inadequate. The loss of nigrostriatal dopamine neurons in PD produces motor symptoms by shifting the balance of striatal output from the direct (go) to indirect (no-go) pathway in large part through changes in the excitatory connections and intrinsic excitabilities of the striatal projection neurons (SPNs). Here, we report using two different experimental models that a transient increase in striatal dopamine and enhanced D1 receptor activation, during 6-OHDA dopamine depletion, prevent the loss of mature spines and dendritic arbors on direct pathway projection neurons (dSPNs) and normal motor behavior for up to 5 months. The primary motor cortex and midline thalamic nuclei provide the major excitatory connections to SPNs. Using ChR2-assisted circuit mapping to measure inputs from motor cortex M1 to dorsolateral dSPNs, we observed a dramatic reduction in both experimental model mice and controls following dopamine depletion. Changes in the intrinsic excitabilities of SPNs were also similar to controls following dopamine depletion. Future work will examine thalamic connections to dSPNs. The findings reported here reveal previously unappreciated plasticity mechanisms within the basal ganglia that can be leveraged to treat the motor symptoms of PD.

16.
Appl Spectrosc ; : 37028241254847, 2024 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-38825581

RESUMO

A wavenumber calibration protocol is proposed that replaces polynomial fitting to relate the detector axis and the wavenumber shift. The physical model of the Raman spectrometer is used to derive a mathematical expression relating the detector plane to the wavenumber shift, in terms of the system parameters including the spectrograph focal length, the grating angle, and the laser wavelength; the model is general to both reflection and transmission gratings. A fast search algorithm detects the set of parameters that best explains the position of spectral lines recorded on the detector for a known reference standard. Using three different reference standards, four different systems, and hundreds of spectra recorded with a rotating grating, we demonstrate the superior accuracy of the technique, especially in bands outside of the outermost reference peaks when compared with polynomial fitting. We also provide a thorough review of wavenumber calibration for Raman spectroscopy and we introduce several new evaluation metrics to this field borrowed from chemometrics, including leave-one-out and leave-half-out cross-validation.

17.
J Am Chem Soc ; 146(22): 15019-15026, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38743719

RESUMO

Electrocatalytic water oxidation is a key transformation in many strategies designed to harness solar energy and store it as chemical fuels. Understanding the mechanism(s) of the best electrocatalysts for water oxidation has been a fundamental chemical challenge for decades. Here, we quantitate evolved dioxygen isotopologue composition via gas-phase EPR spectroscopy to elucidate the mechanisms of water oxidation on metal oxide electrocatalysts with high precision. Isotope fractionation is paired with computational and kinetic modeling, showing that this technique is sensitive enough to differentiate O-O bond-forming steps. Strong agreement between experiment and theory indicates that for the nickel-iron layered double hydroxide─one of the best earth-abundant electrocatalysts to be studied─water oxidation proceeds via a dioxo coupling mechanism to form a side-bound peroxide rather than a hydroxide attack to form an end-bound peroxide.

18.
Ambio ; 2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38795283

RESUMO

Globally, climate warming is increasing air temperatures and changing river flows, but few studies have explicitly considered the consequences for lake temperatures of these dual effects, or the potential to manage lake inflows to mitigate climate warming impacts. Using a one-dimensional model, we tested the sensitivity of lake temperatures to the separate and interacting effects of changes in air temperature and inflow on a small, short-residence time (annual average ≈ 20 days), temperate lake. Reducing inflow by 70% increased summer lake surface temperatures 1.0-1.2 °C and water column stability by 11-19%, equivalent to the effect of 1.2 °C air temperature warming. Conversely, similar increases in inflow could result in lake summer cooling, sufficient to mitigate 0.75 °C air temperature rise, increasing to more than 1.1 °C if inflow temperature does not rise. We discuss how altering lake inflow volume and temperature could be added to the suite of adaptation measures for lakes.

19.
Innovation (Camb) ; 5(4): 100612, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38756954

RESUMO

Environmental pollution is escalating due to rapid global development that often prioritizes human needs over planetary health. Despite global efforts to mitigate legacy pollutants, the continuous introduction of new substances remains a major threat to both people and the planet. In response, global initiatives are focusing on risk assessment and regulation of emerging contaminants, as demonstrated by the ongoing efforts to establish the UN's Intergovernmental Science-Policy Panel on Chemicals, Waste, and Pollution Prevention. This review identifies the sources and impacts of emerging contaminants on planetary health, emphasizing the importance of adopting a One Health approach. Strategies for monitoring and addressing these pollutants are discussed, underscoring the need for robust and socially equitable environmental policies at both regional and international levels. Urgent actions are needed to transition toward sustainable pollution management practices to safeguard our planet for future generations.

20.
J Clin Invest ; 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38743922

RESUMO

Recently developed anti-migraine therapeutics targeting calcitonin gene-related peptide (CGRP) signaling are effective, though their sites of activity remain elusive. Notably, the lymphatic vasculature is responsive to CGRP signaling, but whether meningeal lymphatic vessels (MLVs) contribute to migraine pathophysiology is unknown. Mice with lymphatic vasculature deficient in the CGRP receptor (CalcrliLEC mice) treated with nitroglycerin (NTG)-mediated chronic migraine exhibit reduced pain and light avoidance compared to NTG-treated littermate controls. Gene expression profiles of lymphatic endothelial cells (LECs) isolated from the meninges of Rpl22HA/+;Lyve1Cre RiboTag mice treated with NTG revealed increased MLV-immune interactions compared to cells from untreated mice. Interestingly, the relative abundance of mucosal vascular addressin cell adhesion molecule 1 (MAdCAM1)-interacting CD4+ T cells was increased in the deep cervical lymph nodes of NTG-treated control mice but not in NTG-treated CalcrliLEC mice. Treatment of cultured hLECs with CGRP peptide in vitro induced vascular endothelial (VE)-cadherin rearrangement and reduced functional permeability. Likewise, intra cisterna magna injection of CGRP caused rearrangement of VE-Cadherin, decreased MLV uptake of cerebrospinal fluid (CSF), and impaired CSF drainage in control mice, but not in CalcrliLEC mice. Collectively, these findings reveal a previously unrecognized role for lymphatics in chronic migraine, whereby CGRP signaling primes MLVs-immune interactions and reduces CSF efflux.

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