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1.
PLoS One ; 18(12): e0295893, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38085734

RESUMEN

[This corrects the article DOI: 10.1371/journal.pone.0173335.].

2.
Nano Lett ; 23(17): 8000-8005, 2023 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-37639696

RESUMEN

We investigate the electronic properties of a graphene and α-ruthenium trichloride (α-RuCl3) heterostructure using a combination of experimental techniques. α-RuCl3 is a Mott insulator and a Kitaev material. Its combination with graphene has gained increasing attention due to its potential applicability in novel optoelectronic devices. By using a combination of spatially resolved photoemission spectroscopy and low-energy electron microscopy, we are able to provide a direct visualization of the massive charge transfer from graphene to α-RuCl3, which can modify the electronic properties of both materials, leading to novel electronic phenomena at their interface. A measurement of the spatially resolved work function allows for a direct estimate of the interface dipole between graphene and α-RuCl3. Their strong coupling could lead to new ways of manipulating electronic properties of a two-dimensional heterojunction. Understanding the electronic properties of this structure is pivotal for designing next generation low-power optoelectronics devices.

3.
Microsc Microanal ; 29(Supplement_1): 374-375, 2023 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-37613622
4.
Hand (N Y) ; 18(8): 1342-1348, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35658639

RESUMEN

BACKGROUND: Cost and compliance are 2 factors that can significantly affect the outcomes of non-operative and operative treatment of trigger finger (TF) and both may be influenced by social factors. The purpose of this study was to investigate socioeconomic disparities in the surgical treatment for TF. METHODS: Adult patients (≥18 years old) were identified using International Classification of Diseases 9 and 10 Clinical Modification diagnostic codes for TF and Current Procedural Terminology (CPT) procedural codes (CPT: 26055) in the New York Statewide Planning and Research Cooperative System database. Each diagnosis was linked to procedure data to determine which patients went on to have TF release. A multivariable logistic regression was performed to assess the likelihood of receiving surgery. The variables included in the analysis were age, sex, race, social deprivation index (SDI), Charlson Comorbidity Index, and primary insurance type. A P-value < .05 was considered significant. RESULTS: Of the 31 411 TF patients analyzed, 8941 (28.5%) underwent surgery. Logistic regression analysis showed higher odds of receiving surgery in females (odds ratio [OR]: 1.108) and those with workers compensation (OR: 1.7). Hispanic (OR: 0.541), Asian (OR: 0.419), African American (OR: 0.455), and Other race (OR: 0.45) had decreased odds of surgery. Medicaid (OR: 0.773), Medicare (OR: 0.841), and self-pay (OR: 0.515) reimbursement methods had reduced odds of receiving surgery. Higher social deprivation was associated with decreased odds of surgery (OR: 0.988). CONCLUSIONS: There are disparities in demographic characteristics among those who receive TF release for trigger finger related to race, primary insurance, and social deprivation.


Asunto(s)
Disparidades en Atención de Salud , Trastorno del Dedo en Gatillo , Adolescente , Adulto , Anciano , Femenino , Humanos , Hispánicos o Latinos , Medicaid , Medicare , New York/epidemiología , Trastorno del Dedo en Gatillo/cirugía , Estados Unidos/epidemiología , Disparidades en Atención de Salud/economía , Disparidades en Atención de Salud/etnología , Disparidades en Atención de Salud/estadística & datos numéricos
5.
Artículo en Inglés | MEDLINE | ID: mdl-35960959

RESUMEN

INTRODUCTION: This study seeks to evaluate (1) the relationship between hospital and surgeon volumes of shoulder arthroplasty and complication rates and (2) patient demographics/socioeconomic factors that may affect access to high-volume shoulder arthroplasty care. METHODS: Adults older than 40 years who underwent shoulder arthroplasty between 2011 and 2015 were identified in the New York Statewide Planning and Research Cooperative System database using International Classification of Disease 9/10 and Current Procedural Terminology codes. Medical/surgical complications were compared across surgeon and facility volumes. The effects of demographic factors were analyzed to determine the relationship between such factors and surgeon/facility volume in shoulder arthroplasty. RESULTS: Seven thousand seven hundred eighty-five patients were included. Older, Hispanic/African American, socially deprived, nonprivately insured patients were more likely to be treated by low-volume facilities. Low-volume facilities had higher rates of readmission, urinary tract infection, renal failure, pneumonia, and cellulitis than high-volume facilities. Low-volume surgeons had patients with longer hospital lengths of stay. DISCUSSION: Important differences in patient socioeconomic factors exist in access to high-volume surgical care in shoulder arthroplasty, with older, minority, and underinsured patients markedly more likely to receive care by low-volume surgeons and facilities. This may highlight an area of potential focus to improve access to high-volume care.


Asunto(s)
Artroplastía de Reemplazo de Hombro , Cirujanos , Adulto , Artroplastia , Demografía , Hospitales de Alto Volumen , Humanos
6.
Cogn Sci ; 46(6): e13167, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35678130

RESUMEN

The critical question for cognitive scientists is what does cognitive science do, if anything, for people? Cognitive science is primarily concerned with human cognition but has fallen short in continuously and critically assessing the who in human cognition. This complacency in a world where white supremacist and patriarchal structures leave cognitive science in the unfortunate position of potentially supporting those structures. We take it that many cognitive scientists operate on the assumption that the study of human cognition is both interesting and important. We want to invoke that importance to note that cognitive scientists must continue to work to show how the field is useful to all of humanity and reflects a humanity that is not white by default. We wonder how much the field has done, and can do, to show that it is useful not only in the sense that we might make connections with researchers in other fields, win grants and write papers, even of the highest quality, but useful in some material way to the billions of non-cognitive scientists across the globe.


Asunto(s)
Cognición , Ciencia Cognitiva , Humanos , Escritura
7.
Phys Rev Lett ; 128(14): 147401, 2022 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-35476465

RESUMEN

We use a novel scanning electron Mach-Zehnder interferometer constructed in a conventional transmission electron microscope to perform inelastic interferometric imaging with free electrons. An electron wave function is prepared in two paths that pass on opposite sides of a gold nanoparticle, where plasmons are excited before the paths are recombined to produce electron interference. We show that the measured spectra are consistent with theoretical predictions, specifically that the interference signal formed by inelastically scattered electrons is π out of phase with respect to that formed by elastically scattered electrons. This technique is sensitive to the phase of localized optical modes, because the interference signal amounts to a substantial fraction of the transmitted electrons. Thus, we argue that inelastic interferometric imaging with our scanning electron Mach-Zehnder interferometer provides a new platform for controlling the transverse momentum of free electrons and studying coherent electron-matter interactions at the nanoscale.

8.
J Magn Reson ; 335: 107138, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-35042173

RESUMEN

This paper investigates the possibility of using benchtop NMR spectroscopy for quantification of illicit drugs (methamphetamine) in binary and ternary mixtures with impurities and cutting agents (N-isopropylbenzylamine, phenethylamine and dimethylsulfone). To avoid handling regulated substances, methamphetamine in our experiments is substituted with amino-2-propanol, which has similar functional groups and chemical structure to methamphetamine and hence a related NMR spectrum. Binary and ternary mixtures at concentrations from 30 mmol/L up to 500 mmol/L for each of these species were measured using a 60 MHz benchtop spectrometer. The spectra were analysed using both integration and a model-based algorithm that relies on a full quantum mechanical description of the studied spin systems. Both techniques were able to quantify the composition of the mixtures. The root mean squared error in the measured concentration using the model-based algorithm was < 10 mmol/L, whereas the error using integration was typically > 20 mmol/L. Thus, we conclude benchtop NMR is viable for quantitative measurements of mixtures of illicit substances, particularly when coupled with a quantum mechanical model for the analysis.


Asunto(s)
Drogas Ilícitas , Metanfetamina , Algoritmos , Drogas Ilícitas/análisis , Drogas Ilícitas/química , Imagen por Resonancia Magnética , Espectroscopía de Resonancia Magnética/métodos
9.
Forensic Sci Int ; 329: 111093, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34773817

RESUMEN

Over the last few years there has been a dramatic increase in the amount of "Fantasy" type drugs seized in New Zealand, with gamma-butyrolactone (GBL) being by far the most prevalent. In 2018, N-methyl-2-pyrrolidone (NMP) was detected in a liquid, along with GBL, for the first time in New Zealand. Since this seizure, the number of seizures containing mixtures of GBL and NMP that have been submitted for analysis by New Zealand authorities have significantly increased, with 82% of submitted samples containing GBL also containing NMP. Analysis of these liquids showed that the majority had GBL and NMP purities of approximately 60-70% and 30-40%, respectively. Subsequent investigations by New Zealand authorities revealed a potential source of these liquids being a diverted legitimate industrial product. The health and psychoactive effects of NMP, along with GBL and NMP mixtures, are unknown. Health statistics in New Zealand have indicated increased harm from GBL use over the last few years.

10.
Phys Rev Lett ; 127(11): 110401, 2021 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-34558944

RESUMEN

Here, we experimentally demonstrate interaction-free measurements with electrons using a novel electron Mach-Zehnder interferometer. The flexible two-grating electron interferometer is constructed in a conventional transmission electron microscope and achieves high contrast in discrete output detectors, tunable alignment with independently movable beam splitters, and scanning capabilities for imaging. With this path-separated electron interferometer, which closely matches theoretical expectations, we demonstrate electron interaction-free measurements with an efficiency of 14±1%. Implementing this quantum protocol in electron imaging opens a path toward interaction-free electron microscopy.

12.
Opt Express ; 28(12): 17334-17346, 2020 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-32679943

RESUMEN

Typical methods to holographically encode arbitrary wavefronts assume the hologram medium only applies either phase shifts or amplitude attenuation to the wavefront. In many cases, phase cannot be introduced to the wavefront without also affecting the amplitude. Here we show how to encode an arbitrary wavefront into an off-axis transmission hologram that returns the exact desired arbitrary wavefunction in a diffracted beam for phase-only, amplitude-only, or mixed phase and amplitude holograms with any periodic groove profile. We apply this to design thin holograms for electrons in a TEM, but our results are generally applicable to light and X-ray optics. We employ a phase reconstruction from a series of focal plane images to qualitatively show the accuracy of this method to impart the expected amplitude and phase to a specific diffraction order.

13.
Artículo en Inglés | MEDLINE | ID: mdl-32670197

RESUMEN

Over the last decade, mobile technology has emerged as a potentially useful platform to facilitate weight management and tackle the current obesity epidemic. Clinicians are being more frequently asked to give advice about the usefulness of mobile apps and many individuals have already integrated apps into their attempts to manage weight. Hence, it is imperative for clinicians involved in weight management to be aware of the latest developments and knowledge about available mobile apps and their usefulness in this field. A number of newly published studies have demonstrated promising results of mobile-based interventions for weight management across different populations, but the extent of their effectiveness remains widely debated. This narrative literature review synthesizes the latest evidence, primarily from randomized controlled trials (RCTs), regarding the clinical use of mobile applications for weight management, as well as highlight key limitations associated with their use and directions for future research and practice. Overall, evidence suggests that mobile applications may be useful as low-intensity approaches or adjuncts to conventional weight management strategies. However, there is insufficient evidence to support their use as stand-alone intensive approaches to weight management. Further research is needed to clarify the extent of utility of these applications, as well as the measures required to maximize their potential both as stand-alone approaches and adjuncts to more intensive programs.


Asunto(s)
Peso Corporal , Aplicaciones Móviles/estadística & datos numéricos , Obesidad/prevención & control , Manejo de la Enfermedad , Medicina Basada en la Evidencia , Humanos
14.
Appl Opt ; 59(6): 1594-1601, 2020 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-32225657

RESUMEN

In a transmission electron microscope, electrons are described by matter-waves with wavelengths five orders of magnitude smaller than optical electromagnetic waves. Analogous to optical holography, electron wavefronts can be shaped using nanoscale holographic gratings. Here we demonstrate a novel, scalable nanofabrication method for creating off-axis holographic gratings that demonstrate near ideal diffraction efficiencies for binary, sinusoidal, and blazed grating groove profiles. We show that this method can produce up to 50 µm diameter area gratings that diffract up to 68% of the transmitted electron wave into a desired diffraction order with less than 7% into any other order. Additionally, we find that the amount of inelastically scattered electrons from the material gratings remaining in the coherent diffraction orders from the gratings is negligible in the far field.

15.
Proc (Bayl Univ Med Cent) ; 33(2): 261-262, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32313481

RESUMEN

Metastatic disease to the oral and maxillofacial region is rare, with only about 1% of oral malignancy attributed to metastases. In approximately 20% of these patients, oral metastases are discovered before the detection of the primary tumor. Here we present a case of a 66-year-old man who presented with vague left mandibular pain and new-onset lip numbness as the first sign of occult malignancy from lung adenocarcinoma with multiple metastases.

16.
Drug Test Anal ; 12(2): 195-214, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31595682

RESUMEN

We describe the validation of a method for the simultaneous analysis of 29 synthetic cannabinoids (SCs) and metabolites, 4 amphetamines, and 2 cannabinoids in human whole blood. This method enables one analysis to cover what previously required multiple analyses for these classic and novel drugs-of-abuse with diverse physicochemical properties. The scope of targeted analytes was based on the most prevalent drugs-of-abuse and SCs encountered at the New Zealand border in 2017 and included parent compounds and metabolites belonging to the indole and indazole carboxamide, quinolinyl indole carboxylate, and naphthoylindole classifications. Samples were prepared by supported-liquid-extraction (SLE) followed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis with positive electrospray ionization (ESI). The method was validated with respect to selectivity, matrix effects, process efficiency, sensitivity, repeatability, extract stability, and carryover for qualitative confirmation. Linearity as well as accuracy and precision data at target decision concentrations were also evaluated. The limits of detection and confirmation ranged from 0.1 to 6.0 ng/mL and 1.0 to 6.0 ng/mL, respectively. The described method was successfully applied to the analysis of 564 ante- and post-mortem blood samples in 2018. There were 132 cases (23%) with positive findings of at least one SC, with the five most commonly detected SCs being AMB-FUBINACA and/or acid (61%), 5F-ADB and/or acid (40%), ADB-FUBINACA (11%), 5F-MDMB-PICA acid (6%), and MDMB-FUBINACA acid (6%). The results also demonstrate the predominant presence of metabolites at higher levels than the unchanged parent SCs in blood, highlighting the need to maintain forensic screening methods capable of the simultaneous detection of both parent compounds and metabolites.


Asunto(s)
Anfetaminas/sangre , Cannabinoides/sangre , Drogas Ilícitas/sangre , Detección de Abuso de Sustancias/métodos , Espectrometría de Masas en Tándem/métodos , Anfetaminas/metabolismo , Cannabinoides/metabolismo , Cromatografía Liquida/métodos , Humanos , Drogas Ilícitas/metabolismo , Límite de Detección , Extracción Líquido-Líquido/métodos , Nueva Zelanda
17.
J Mol Endocrinol ; 63(2): 123-138, 2019 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-31357177

RESUMEN

It has been hypothesized that transcriptional changes associated with lower mTORC1 activity in mice with reduced levels of growth hormone and insulin-like growth factor 1 are responsible for the longer healthy lifespan of these mutant mice. Cell lines and tissues from these mice show alterations in the levels of many proteins that cannot be explained by corresponding changes in mRNAs. Such post-transcriptional modulation may be the result of preferential mRNA translation by the cap-independent translation of mRNA bearing the N6-methyl-adenosine (m6A) modification. The long-lived endocrine mutants - Snell dwarf, growth hormone receptor deletion and pregnancy-associated plasma protein-A knockout - all show increases in the N6-adenosine-methyltransferases (METTL3/14) that catalyze 6-methylation of adenosine (m6A) in the 5' UTR region of select mRNAs. In addition, these mice have elevated levels of YTH domain-containing protein 1 (YTHDF1), which recognizes m6A and promotes translation by a cap-independent mechanism. Consistently, multiple proteins that can be translated by the cap-independent mechanism are found to increase in these mice, including DNA repair and mitochondrial stress response proteins, without changes in corresponding mRNA levels. Lastly, a drug that augments cap-independent translation by inhibition of cap-dependent pathways (4EGI-1) was found to elevate levels of the same set of proteins and able to render cells resistant to several forms of in vitro stress. Augmented translation by cap-independent pathways facilitated by m6A modifications may contribute to the stress resistance and increased healthy longevity of mice with diminished GH and IGF-1 signals.


Asunto(s)
Sistema Endocrino/metabolismo , Longevidad , Mutación/genética , Biosíntesis de Proteínas , Caperuzas de ARN/metabolismo , Regulación hacia Arriba , Adenosina/análogos & derivados , Adenosina/metabolismo , Animales , Fibroblastos/metabolismo , Humanos , Hidrazonas/farmacología , Hígado/efectos de los fármacos , Hígado/metabolismo , Hígado/patología , Ratones Noqueados , Ratones Mutantes , Proteolisis , ARN Mensajero/genética , ARN Mensajero/metabolismo , Proteínas de Unión al ARN/metabolismo , Receptores de Somatotropina/deficiencia , Receptores de Somatotropina/metabolismo , Tiazoles/farmacología , Regulación hacia Arriba/efectos de los fármacos
19.
Plant Physiol ; 177(3): 1198-1217, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29844229

RESUMEN

Long noncoding RNAs (lncRNAs) have been characterized extensively in animals and are involved in several processes, including homeobox gene expression and X-chromosome inactivation. In comparison, there has been much less detailed characterization of plant lncRNAs, and the number of distinct lncRNAs encoded in plant genomes and their regulation by developmental and epigenetic mechanisms remain largely unknown. Here, we analyzed transcriptome data from Asian rice (Oryza sativa) and identified 6,309 long intergenic noncoding RNAs (lincRNAs), focusing on their expression in reproductive tissues and organs. Most O. sativa lincRNAs were expressed in a highly tissue-specific manner, with an unexpectedly high fraction specifically expressed in male gametes. Mutation of a component of the Polycomb Repressive Complex2 (PRC2) resulted in derepression of another large class of lincRNAs, whose expression is correlated with H3K27 trimethylation in developing panicles. Overlap with the sperm cell-specific lincRNAs suggests that epigenetic repression of lincRNAs in the panicles was partially relieved in the male germline. Expression of a subset of lincRNAs also showed modulation by drought in reproductive tissues. Comparison with other cereal genomes showed that the lincRNAs generally have low levels of conservation at both the sequence and structural levels. Use of a novelty detection support vector machine model enabled the detection of nucleotide sequence and structural homology in ∼10% and ∼4% of the lincRNAs in genomes of purple false brome (Brachypodium distachyon) and maize (Zea mays), respectively. This is the first study to report on a large number of lncRNAs that are targets of repression by PRC2 rather than mediating regulation via PRC2. That the vast majority of the lincRNAs reported here do not overlap with those of other rice studies indicates that these are a significant addition to the known lincRNAs in rice.


Asunto(s)
Oryza/genética , Polen/genética , Complejo Represivo Polycomb 2/genética , ARN Largo no Codificante/genética , Secuencia de Bases , Brachypodium/genética , Cromatina/genética , Secuencia Conservada , Sequías , Represión Epigenética , Regulación de la Expresión Génica de las Plantas , Metilación , Complejo Represivo Polycomb 2/metabolismo , ARN de Planta , Alineación de Secuencia/métodos , Máquina de Vectores de Soporte
20.
Plant Cell Physiol ; 59(1): 179-189, 2018 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-29145642

RESUMEN

The plant hormone auxin plays critical roles in plant growth and development. Auxin response factors (ARFs) are a class of transcription factors which regulate auxin-mediated gene expression. While the functions of ARFs in sporophytic development have been well characterized, their functions specific to gametophytic development have not been studied extensively. In this study, Arabidopsis ARF genes were selectively down-regulated in gametophytes by misexpression of targeted microRNAs (amiRARF234, amiRARFMP and MIR167a) to silence AtARF2-AtAEF4, AtARF5, AtARF6 and AtARF8. Embryo sacs in amiRARF234- and amiRARFMP-expressing plants exhibited identity defects in cells at the micropylar pole, such as formation of two cells with egg cell-like morphology, concomitant with loss of synergid marker expression and seed abortion. The pollen grains of the transgenic plants were morphologically aberrant and unviable, and the inclusions and nuclei were lost in the abnormal pollen grains. However, plants misexpressing MIR167a showed no obvious abnormal phenotypes in the embryo sacs and pollen grains. Overall, these results provide evidence that AtARF2-AtARF4 and AtARF5 play significant roles in regulating both female and male gametophyte development in Arabidopsis.


Asunto(s)
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Proteínas de Unión al ADN/genética , Gametogénesis en la Planta/genética , Proteínas Nucleares/genética , Proteínas Represoras/genética , Factores de Transcripción/genética , Arabidopsis/crecimiento & desarrollo , Secuencia de Bases , Regulación hacia Abajo , Regulación del Desarrollo de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Células Germinativas de las Plantas/crecimiento & desarrollo , Células Germinativas de las Plantas/metabolismo , Células Germinativas de las Plantas/ultraestructura , Microscopía Electrónica de Transmisión , Plantas Modificadas Genéticamente , Semillas/genética , Semillas/crecimiento & desarrollo , Homología de Secuencia de Ácido Nucleico
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