Atomic layer deposition of BN as a novel capping barrier for B2O3

Article demonstrating in situ deposition of BN by sequential BCl₃/NH₃ reactions at 600 K on two different oxidized boron substrates: (a) B₂O₃ deposited using BCl₃/H₂O ALD on Si at 300 K (“B₂O₃/Si”) and (b) a boron-silicon oxide formed by sequential BCl₃/O₂ reactions at 650 K on SiO₂ followed by annealing to 1000 K (“B-Si-oxide”). The data presented demonstrates that ultrathin BN films deposited by BCl₃/NH₃ ALD are promising candidates for passivation of boron oxide used in shallow doping applications

Characterization of basal ganglia volume changes in the context of HIV and polysubstance use

HIV and psychoactive substances can impact the integrity of the basal ganglia (BG), a neural substrate of cognition, motor control, and reward-seeking behaviors. This study assessed BG gray matter (GM) volume as a function of polysubstance (stimulant and opioid) use and HIV status. We hypothesized that comorbid polysubstance use and HIV seropositivity would alter BG GM volume differently than would polysubstance use or HIV status alone. We collected structural MRI scans, substance use history, and HIV diagnoses. Participants who had HIV (HIV +), a history of polysubstance dependence (POLY +), both, or neither completed assessments for cognition, motor function, and risk-taking behaviors (N = 93). All three clinical groups showed a left-lateralized pattern of GM reduction in the BG relative to controls. However, in the HIV + /POLY + group, stimulant use was associated with increased GM volume within the globus pallidus and putamen. This surpassed the effects from opioid use, as indicated by decreased GM volume throughout the BG in the HIV-/POLY + group. Motor learning was impaired in all three clinical groups, and in the HIV + /POLY + group, motor learning was associated with increased caudate and putamen GM volume. We also observed associations between BG GM volume and risk-taking behaviors in the HIV + /POLY- and HIV-/POLY + groups. The effects of substance use on the BG differed as a function of substance type used, HIV seropositivity, and BG subregion. Although BG volume decreased in association with HIV and opioid use, stimulants can, inversely, lead to BG volume increases within the context of HIV

Neuroendocrine Differentiation of Prostate Cancer—An Intriguing Example of Tumor Evolution at Play

Our understanding of neuroendocrine prostate cancer (NEPC) has assumed a new perspective in light of the recent advances in research. Although classical NEPC is rarely seen in the clinic, focal neuroendocrine trans-differentiation of prostate adenocarcinoma occurs in about 30% of advanced prostate cancer (PCa) cases, and represents a therapeutic challenge. Even though our knowledge of the mechanisms that mediate neuroendocrine differentiation (NED) is still evolving, the role of androgen deprivation therapy (ADT) as a key driver of this phenomenon is increasingly becoming evident. In this review, we discuss the molecular, cellular, and therapeutic mediators of NED, and emphasize the role of the tumor microenvironment (TME) in orchestrating the phenotype. Understanding the role of the TME in mediating NED could provide us with valuable insights into the plasticity associated with the phenotype, and reveal potential therapeutic targets against this aggressive form of PCa

Atomic layer deposition of h-BN(0001) multilayers on Ni(111) and chemical vapor deposition of graphene on h-BN(0001)/Ni(111)

Article studying atomic layer deposition. In situ direct, epitaxial growth of multilayers of hexagonal boron nitride (h-BN) and graphene without physical transfer is of significant interest for the scalable production of graphene/h-BN heterostructures for device applications. Deposition on magnetic substrates is of particular interest for spin tunneling applications. X-ray photoelectron spectroscopy and low energy electron diffraction demonstrate epitaxial atomic-layer deposition (ALD) of multilayer h-BN(0001) on Ni(111) and subsequent deposition of azimuthally-aligned multilayer graphene on h-BN(0001)/Ni(111) by chemical vapor deposition. Boron nitride ALD was accomplished with alternating cycles of BCl₃/NH₃ at a 600 K substrate temperature, and subsequent annealing in ultrahigh vacuum. Subsequent deposition of graphene was achieved by chemical vapor deposition using ethylene (CH₂CH₂) at 1000 K

Mentoring Relationships: A Mentee’s Journey

[Extract] Mentoring relationships are ideally driven by mentees and help mentees to tackle professional challenges and/or plan career development. Mentees can choose from several mentoring formats: senior, near peer, within or outside the institution, dyadic or network, in person or virtual. Regardless of the format, mentors guide key stages of mentee professional development, balance challenging and supporting the mentee, and help the mentee to reflect and make informed decisions. The figure below illustrates how a mentee starts the journey by identifying potential mentors, meets the mentor to discuss aspirations and challenges, and formulates next steps guided by the mentor. The mentee is the architect, and the mentor is the facilitator and guide. A short- or long-term mentoring relationship can be forged based on goals and compatibility. As depicted by the ladders in the figure below, mentoring relationships may require backward jumps and restarts to deal with changing circumstances

Delayed repolarization and ventricular tachycardia in patients with heart failure and preserved ejection fraction

Sudden death is the most common mode of mortality in patients with heart failure and preserved ejection fraction (HFpEF). Ventricular arrhythmias (VA) have been suspected as the etiology but the supporting evidence in patients with HFpEF is scarce. We sought to investigate VA prevalence, and to determine if VA are associated with prolonged repolarization, in patients with HFpEF. In a retrospective case-control study design, Cedars-Sinai patients who underwent prolonged ambulatory electrocardiographic monitoring (Zio Patch) between 2016 and 2018 were screened for a clinical diagnosis of HFpEF. Patients with normal diastolic and systolic function who underwent Zio Patch monitoring were also reviewed as controls. Multivariable logistic regression was used to compare the prevalence of rhythm disturbances in patients with and without HFpEF. Ventricular tachycardia (VT) was more prevalent in patients with HFpEF (37% vs. 16% in controls, p = 0.001). Most episodes were non-sustained except for one case of sustained VT in a patient with HFpEF. Covariate-adjusted logistic regression including HFpEF diagnosis, age, sex, body mass index, and the presence of comorbidities revealed that only HFpEF was associated with increased risk of VT (relative risk 2.86, p = 0.023). Subgroup-analyses revealed an association between increased QTc interval and risk of VT (460 ± 38 ms in HFpEF patients with VT vs. 445 ± 28 ms in HFpEF patients without VT, p = 0.03). Non-sustained VT was more prevalent in patients with HFpEF compared to patients without HFpEF, and QTc interval prolongation was associated with VT in HFpEF

Residential Proximity to Major Roadways Is Associated With Increased Levels of AC133+ Circulating Angiogenic Cells

Objectives?Previous studies have shown that residential proximity to a roadway is associated with increased cardiovascular disease risk. Yet, the nature of this association remains unclear, and its effect on individual cardiovascular disease risk factors has not been assessed. The objective of this study was to determine whether residential proximity to roadways influences systemic inflammation and the levels of circulating angiogenic cells.Approach and Results?In a cross-sectional study, cardiovascular disease risk factors, blood levels of C-reactive protein, and 15 antigenically defined circulating angiogenic cell populations were measured in participants (n=316) with moderate-to-high cardiovascular disease risk. Attributes of roadways surrounding residential locations were assessed using geographic information systems. Associations between road proximity and cardiovascular indices were analyzed using generalized linear models. Close proximity

Acrolein exposure is associated with increased cardiovascular disease risk

Background Acrolein is a reactive aldehyde present in high amounts in coal, wood, paper, and tobacco smoke. It is also generated endogenously by lipid peroxidation and the oxidation of amino acids by myeloperoxidase. In animals, acrolein exposure is associated with the suppression of circulating progenitor cells and increases in thrombosis and atherogenesis. The purpose of this study was to determine whether acrolein exposure in humans is also associated with increased cardiovascular disease (CVD) risk. Methods and Results Acrolein exposure was assessed in 211 participants of the Louisville Healthy Heart Study with moderate to high (CVD) risk by measuring the urinary levels of the major acrolein metabolite?3-hydroxypropylmercapturic acid (3-HPMA). Generalized linear models were used to assess the association between acrolein exposure and parameters of CVD risk, and adjusted for potential demographic confounders. Urinary 3-HPMA levels were higher in smokers than nonsmokers and were positively correlated with urinary cotinine levels. Urinary 3-HPMA levels were inversely related to levels of both early (AC133+) and late (AC133?) circulating angiogenic cells. In smokers as well as nonsmokers, 3-HPMA levels were positively associated with both increased levels of platelet?leukocyte aggregates and the Framingham Risk Score. No association was observed between 3-HPMA and plasma fibrinogen. Levels of C-reactive protein were associated with 3-HPMA levels in nonsmokers only. Conclusions Regardless of its source, acrolein exposure is associated with platelet activation and suppression of circulating angiogenic cell levels, as well as increased CVD risk