Publications by authors named "Acosta V"

Article Synopsis
  • * Researchers used a specialized magnetic microscope to image the magnetic fields from many isolated SPIONs, discovering distinct magnetization patterns that traditional methods wouldn't reveal.
  • * The study also recorded SPION relaxation times after an applied magnetic field was turned off, showing a wide range of characteristics among the nanoparticles, indicating their varied behavior and potential for further nanomagnetism research.
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Native Hawaiian and Pacific Islanders (NHPIs) are overrepresented in Hawai'i's houseless population. Indigenous populations, such as NHPIs, may encounter experiences of historical trauma that impact their well-being. This original research project examines how NHPI identity and houselessness compound to affect the perceived stress and historical trauma of transition-aged youth.

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Many undergraduate neuroscience trainees aspire to earn a PhD. In recent years the number, demographics, and previous experiences of PhD applicants in neuroscience has changed. This has necessitated both a reconsideration of admissions processes to ensure equity for an increasingly diverse applicant pool as well as renewed efforts to expand access to the training and research experiences required for admission to graduate programs.

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Aging increases breast cancer risk while an early first pregnancy reduces a woman's life-long risk. Several studies have explored the effect of either aging or pregnancy on mammary epithelial cells (MECs), but the combined effect of both remains unclear. Here, we interrogate the functional and transcriptomic changes at single cell resolution in the mammary gland of aged nulliparous and parous mice to discover that pregnancy normalizes age-related imbalances in lineage composition, while also inducing a differentiated cell state.

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Substance use disorder (SUD) is a heterogeneous disorder, where severity, symptoms, and patterns of use vary across individuals. Yet, when rats self-administer cocaine under short-access conditions, their behavior tends to be well-regulated, though individual differences can emerge with long- or intermittent-access. In contrast, significant individual differences emerge when rats self-administer 3,4-methylenedioxypyrovalerone (MDPV), even under short-access conditions, wherein ~30 % of rats exhibit high levels of drug-taking.

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One of the initial causes of cystic ovarian disease (COD) is a failure in the normal ovulation mechanism. This study aimed to characterize the populations of immune cells (T-lymphocytes, B-lymphocytes, monocytes-macrophages and granulocytes) present in the ovary of cows with COD and induced follicular persistence, and evaluate their relation with follicular persistence and cyst formation. The follicular persistence model was developed using a progesterone (P4) slow-release intravaginal device, to obtain subluteal concentrations of P4.

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Article Synopsis
  • Latex allergy (NRLA) is a significant global health issue, particularly affecting children, with symptoms ranging from mild irritation to severe anaphylactic reactions.
  • Latex is sourced from the Hevea Brasiliensis tree, and despite safety measures, NRLA remains common, especially in vulnerable groups like children with spina bifida.
  • Effective diagnosis involves medical history and tests, while prevention mainly focuses on minimizing exposure, and treatment options like immunotherapy show mixed results, impacting the quality of life for affected children.
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We measure electron- and nuclear-spin transition frequencies in the ground state of nitrogen-vacancy (N-) centers in diamond for two nitrogen isotopes (N- and N-) over temperatures ranging from 77 to 400 K. Measurements are performed using Ramsey interferometry and direct optical readout of the nuclear and electron spins. We extract coupling parameters (for N-), , , , and , and their temperature dependences for both isotopes.

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Substance use disorder (SUD) is a heterogeneous disorder, where severity, symptoms, and patterns of substance use vary across individuals. Yet, when rats are allowed to self-administer drugs such as cocaine under short-access conditions, their behavior tends to be well-regulated and homogeneous in nature; though individual differences can emerge when rats are provided long- or intermittent-access to cocaine. In contrast to cocaine, significant individual differences emerge when rats are allowed to self-administer 3,4-methylenedioxypyrovalerone (MDPV), even under short-access conditions, wherein ~30% of rats rapidly transition to high levels of drug-taking.

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Scanning-probe and wide-field magnetic microscopes based on nitrogen-vacancy (NV) centers in diamond have enabled advances in the study of biology and materials, but each method has drawbacks. Here, we implement an alternative method for nanoscale magnetic microscopy based on optical control of the charge state of NV centers in a dense layer near the diamond surface. By combining a donut-beam super-resolution technique with optically detected magnetic resonance spectroscopy, we imaged the magnetic fields produced by single 30 nm iron-oxide nanoparticles.

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Scanning-probe and wide-field magnetic microscopes based on Nitrogen-Vacancy (NV) centers in diamond have enabled remarkable advances in the study of biology and materials, but each method has drawbacks. Here, we implement an alternative method for nanoscale magnetic microscopy based on optical control of the charge state of NV centers in a dense layer near the diamond surface. By combining a donut-beam super-resolution technique with optically detected magnetic resonance spectroscopy, we imaged the magnetic fields produced by single 30-nm iron-oxide nanoparticles.

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Radio frequency (RF) magnetometers based on nitrogen vacancy centers in diamond are predicted to offer femtotesla sensitivity, but previous experiments were limited to the picotesla level. We demonstrate a femtotesla RF magnetometer using a diamond membrane inserted between ferrite flux concentrators. The device provides ~300-fold amplitude enhancement for RF magnetic fields from 70 kHz to 3.

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We demonstrate the operation of a rotation sensor based on the nitrogen-14 (N) nuclear spins intrinsic to nitrogen-vacancy (NV) color centers in diamond. The sensor uses optical polarization and readout of the nuclei and a radio-frequency double-quantum pulse protocol that monitors N nuclear spin precession. This measurement protocol suppresses the sensitivity to temperature variations in the N quadrupole splitting, and it does not require microwave pulses resonant with the NV electron spin transitions.

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Purpose: There appears to be a negative association between reported microaggressions and mental health. Due to the subjective nature of microaggressions, however, certain factors may affect whether an interaction is perceived as microaggressive. This study investigated perceptions of microaggressions and neutral interactions, and influencing factors.

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Polymeric separators have been developed since 2010 to produce acoustophoretic separation of particles or cells in suspension with high efficiency. They rely on three-dimensional (3D) resonances of their whole structure actuated by ultrasounds. In this paper, a numerical 3D analysis is presented and validated as the only tool for optimization of these polymeric chips to perform efficient separation applications.

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Magnetometers based on nitrogen-vacancy (NV) centers in diamond are promising room-temperature, solid-state sensors. However, their reported sensitivity to magnetic fields at low frequencies (≾1 kHz) is presently ≿10 pT s, precluding potential applications in medical imaging, geoscience, and navigation. Here we show that high-permeability magnetic flux concentrators, which collect magnetic flux from a larger area and concentrate it into the diamond sensor, can be used to improve the sensitivity of diamond magnetometers.

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Article Synopsis
  • A 58-year-old man received bilateral proximal forearm transplants in 2012 and was monitored for 7 years to assess long-term functional outcomes.
  • After the transplant, he experienced some complications, including hypertriglyceridemia and systemic hypertension, but managed to maintain a significant level of grip strength and overall function in his arms.
  • By the end of the study, while he had improved limb strength and functional use of his elbow and wrist, he experienced some loss of fine motor skills and sensation, suggesting that proximal forearm transplantation can be beneficial for selected patients.
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Quantum sensors based on nitrogen-vacancy centers in diamond have emerged as a promising detection modality for nuclear magnetic resonance (NMR) spectroscopy owing to their micrometer-scale detection volume and noninductive-based detection. A remaining challenge is to realize sufficiently high spectral resolution and concentration sensitivity for multidimensional NMR analysis of picoliter sample volumes. Here, we address this challenge by spatially separating the polarization and detection phases of the experiment in a microfluidic platform.

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Magnetic microscopy of malarial hemozoin nanocrystals is performed by optically detected magnetic resonance imaging of near-surface diamond nitrogen-vacancy centers. Hemozoin crystals are extracted from -infected human blood cells and studied alongside synthetic hemozoin crystals. The stray magnetic fields produced by individual crystals are imaged at room temperature as a function of the applied field up to 350 mT.

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Introduction: Flat panel imaging for emergent large vessel occlusion can be acquired prior to mechanical thrombectomy (MT). In this study, we examined patients undergoing MT with computed tomography angiography (CTA) to determine agreement on the site of occlusion and CTA collateral score (CS).

Methods: Flat Panel CTA (FP-CTA) was acquired before MT.

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Introduction: Cigarette consumption among teenagers is one of the most critical health-related risk behaviors.

Method: Prospective study carried out in seven sites of five Latin American countries (Argentina [Cordoba, N=958, Corrientes, N=1013], Brazil [Curitiba, N=650; Uruguaiana, N=997], Cuba [Havana, N=1004], Mexico [Veracruz, N=991] and Paraguay [Ciudad del Este, N=868]) with public-school adolescents (aged 12-19 years). Respondents were asked to answer the California Student Tobacco Survey.

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Cognitive decline with aging is often due to altered levels of protein expression. The NMDA receptor (NMDAR) and the complex of proteins surrounding the receptor are susceptible to age-related changes in expression. In the frontal cortex of aged mice, there is a significant loss of expression of the GluN2B subunit of the NMDAR, an increase in Fyn expression, and no change in PSD-95.

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We propose a hybrid laser system consisting of a semiconductor external cavity laser associated to an intra-cavity diamond etalon doped with nitrogen-vacancy color centers. We consider laser emission tuned to the infrared absorption line that is enhanced under the magnetic field dependent nitrogen-vacancy electron spin resonance and show that this architecture leads to a compact solid-state magnetometer that can be operated at room-temperature. The sensitivity to the magnetic field limited by the photonshot-noise of the output laser beam is estimated to be less than 1 pT/Hz.

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Poor dietary patterns are associated with coronary artery disease (CAD) and cardiovascular events. The aim of this study was to determine whether reported dietary patterns change after undergoing invasive coronary angiography. Participants without a history of coronary revascularization were prospectively enrolled before undergoing coronary angiography at a tertiary center between February 2015 and February 2017.

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Regulation of the Wnt pathway in stem cells and primary tissues is still poorly understood. Here we report that Usp16, a negative regulator of Bmi1/PRC1 function, modulates the Wnt pathway in mammary epithelia, primary human fibroblasts and MEFs, affecting their expansion and self-renewal potential. In mammary glands, reduced levels of Usp16 increase tissue responsiveness to Wnt, resulting in upregulation of the downstream Wnt target Axin2, expansion of the basal compartment and increased in vitro and in vivo epithelial regeneration.

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