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1.
Nanomaterials (Basel) ; 14(7)2024 Mar 22.
Article in English | MEDLINE | ID: mdl-38607096

ABSTRACT

Samaria-doped ceria (SDC) overlayers were deposited on Ag cathodes by sputtering. The SDC sputtering time was varied to investigate the properties of the Ag-SDC overlayer cathode-coated fuel cells depending on the thickness of the SDC overlayers. Among the fabricated fuel cells, Ag with a 10-nm-thick SDC overlayer (Ag-SDC10) cathode-coated fuel cell exhibited the highest peak power density of 6.587 mW/cm2 at 450 °C, showing higher performance than a pristine Pt-coated fuel cell. Moreover, electrochemical impedance spectroscopy revealed that the Ag-SDC10 cathode-coated fuel cell significantly mitigated polarization loss originating from enhanced oxygen reduction reaction kinetics compared to the pristine Ag-coated fuel cell.

2.
Inflamm Bowel Dis ; 2023 Oct 20.
Article in English | MEDLINE | ID: mdl-37861390

ABSTRACT

BACKGROUND: Outcomes of inflammatory bowel disease (IBD) following flare complicated by enteric infection (EI) are limited by follow-up duration and insufficient assessment of the role of non-Clostridioides difficile pathogens. We compared 2-year IBD outcomes following flare with and without EI. METHODS: We performed a retrospective cohort study of adults evaluated with stool PCR testing for IBD flare. Subjects were stratified by presence of EI at flare and were matched for age, sex, and date to those without EI. The primary outcome was a composite of steroid-dependent IBD, colectomy, and/or IBD therapy class change/dose escalation at 2 years. Additional analyses were performed by dividing the EI group into C. difficile infection (CDI) and non-CDI EI, and further subdividing non-CDI EI into E. coli subtypes and other non-CDI EI. RESULTS: We identified 137 matched subjects, of whom 62 (45%) had EI (40 [29%] CDI; 17 [12%] E. coli). Enteric infection at flare was independently associated with the primary outcome (adjusted odds ratio, 4.14; 95% confidence interval [CI], 1.62-11.5). After dividing EI into CDI and non-CDI EI, only CDI at flare was independently associated with the primary outcome (adjusted odds ratio, 4.04; 95% CI, 1.46-12.6). After separating E. coli subtypes from non-CDI EI, E. coli infection and CDI at flare were both independently associated with the primary outcome; other EI was not. CONCLUSIONS: Enteric infection at flare-specifically with CDI-is associated with worse IBD outcomes at 2 years. The relationship between E. coli subtypes at flare and subsequent IBD outcomes requires further investigation.


Enteric infection complicating IBD flare is associated with worse IBD outcomes at 2 years compared with flare without infection. Clostridioides difficile is implicated in this relationship, but Escherichia coli may also have a contributing role.

3.
Nanomaterials (Basel) ; 13(5)2023 Feb 27.
Article in English | MEDLINE | ID: mdl-36903764

ABSTRACT

This study demonstrated a silver (Ag) and samarium-doped ceria (SDC) mixed ceramic and metal composite (i.e., cermet) as a cathode for low-temperature solid oxide fuel cells (LT-SOFCs). Introducing the Ag-SDC cermet cathode for LT-SOFCs revealed that the ratio between Ag and SDC, which is a crucial factor for catalytic reactions, can be tuned by the co-sputtering process, resulting in enhanced triple phase boundary (TPB) density in the nanostructure. Ag-SDC cermet not only successfully performed as a cathode to increase the performance of LT-SOFCs by decreasing polarization resistance but also exceeded the catalytic activity of platinum (Pt) due to the improved oxygen reduction reaction (ORR). It was also found that less than half of Ag content was effective to increase TPB density, preventing oxidation of the Ag surface as well.

5.
BMC Gastroenterol ; 22(1): 236, 2022 May 12.
Article in English | MEDLINE | ID: mdl-35550029

ABSTRACT

BACKGROUND: Capsule endoscopy (CE) provides a novel approach to evaluate obscure gastrointestinal bleeding. Yet CE is not routinely utilized in the inpatient setting for a variety of reasons. We sought to identify factors that predict complete CE and diagnostically meaningful CE, as well as assess the impact of inpatient CE on further hospital management.1 na d2 METHODS: We conducted a retrospective review of patients undergoing inpatient CE at a tertiary referral, academic center over a 3 year period. We analyzed data on patient demographics, medical history, endoscopic procedures, hospital course, and results of CE. The primary outcome was complete CE and the secondary outcome was positive findings of pathology on CE. RESULTS: 131 patients were included (56.5% were men 43.5% women, median age of 71.0 years). Overall, CE was complete in 77.1% of patients. Complete CE was not related to motility risk factors, gender, or administration modality. Patients with incomplete CE tended to be older, have lower BMI, and Caucasian, however results did not reach statistical significance (p = 0.06; p = 0.06; p = 0.08 respectively). Positive CE was noted in 73.3% of patients, with 35.1% of all patients having active bleeding. Positive CE was not associated with AVM risk factors or medication use. 28.0% of patients underwent subsequent hospital procedures, among which 67.6% identified the same pathology seen on CE. CONCLUSIONS: Contrary to previous studies, we found the majority of inpatient CEs were complete and positive for pathology. We found high rates of correlation between CE and subsequent procedures. The use of CE in the inpatient setting helps to guide the diagnosis and treatment of hospitalized patients with obscure gastrointestinal bleeding.


Subject(s)
Capsule Endoscopy , Aged , Capsule Endoscopy/adverse effects , Endoscopy, Gastrointestinal/methods , Female , Gastrointestinal Hemorrhage/diagnosis , Gastrointestinal Hemorrhage/etiology , Gastrointestinal Hemorrhage/pathology , Humans , Inpatients , Male , Referral and Consultation , Retrospective Studies
6.
Inflamm Bowel Dis ; 27(10): 1634-1640, 2021 10 18.
Article in English | MEDLINE | ID: mdl-33386740

ABSTRACT

BACKGROUND: Differentiating between enteric infection and relapse of inflammatory bowel disease (IBD) is a common clinical challenge. Few studies have evaluated the impact of multiplex gastrointestinal polymerase chain reaction (GI PCR) pathogen panels on clinical practice compared to stool culture. Our aim was to compare the impact of PCR stool testing to conventional stool testing in outpatients presenting with relapse of IBD. METHODS: In a retrospective cohort study of outpatients with IBD presenting to NYU Langone Health with flare from September 2015 to April 2019, we compared patients who underwent stool testing with GI PCR to age-, sex-, and IBD-subtype-matched patients who underwent culture and ova and parasite exam (conventional testing). The primary outcome was IBD therapy escalation after testing. Secondary outcomes included rates of posttesting endoscopy, abdominal radiography, antibiotics, and IBD-related emergency department visits, hospitalizations, and abdominal surgeries. RESULTS: We identified 134 patients who underwent GI PCR matched to 134 patients who underwent conventional testing. Pathogens were more frequently identified on GI PCR (26 vs 5%; P < 0.01). We found that GI PCR was associated with less escalation in IBD therapy (16 vs 29%; P < 0.01) and fewer posttest endoscopies (10% vs 18%; P = 0.04), with no differences in IBD outcomes. On multivariate analysis, testing with GI PCR was associated with an odds ratio of 0.26 (95% confidence interval, 0.08-0.84; P = 0.02) for escalation of IBD therapies. CONCLUSIONS: Testing with GI PCR was associated with higher rates of pathogen detection and lower rates of IBD therapy escalation and endoscopy in the outpatient setting. These changes in management were not associated with a difference in IBD outcomes.


Subject(s)
Colitis , Inflammatory Bowel Diseases , Chronic Disease , Feces , Humans , Inflammatory Bowel Diseases/diagnosis , Outpatients , Recurrence , Retrospective Studies
7.
ACS Appl Mater Interfaces ; 11(44): 41338-41346, 2019 Nov 06.
Article in English | MEDLINE | ID: mdl-31603644

ABSTRACT

In this Research Article, gadolinia-doped ceria (GDC), which is a highly catalyzed oxide ionic conductor, was explored to further improve oxygen surface reaction rates using a grain-controlled layer (GCL) concept. Typically, GDC materials have been used as a cathode functional layer by coating the GDC between the electrode and electrolyte to accelerate the oxygen reduction reaction (ORR). To further improve the oxygen surface kinetics of the GDC cathodic layer, we modified the grain boundary density and crystallinity developed in the GDC layer by adjusting RF power conditions during the sputtering process. This approach revealed that engineered nanograins of GDC thin films directly affected ORR kinetics by catalyzing the oxygen surface reaction rate, significantly enhancing the fuel cell performance. Using this innovative concept, the fuel cells fabricated with a GDC GCL demonstrated a peak power density of 240 mW/cm2 at 450 °C.

8.
Neuron ; 92(5): 1049-1062, 2016 Dec 07.
Article in English | MEDLINE | ID: mdl-27866800

ABSTRACT

Little is known about how animals integrate multiple sensory inputs in natural environments to balance avoidance of danger with approach to things of value. Furthermore, the mechanistic link between internal physiological state and threat-reward decision making remains poorly understood. Here we confronted C. elegans worms with the decision whether to cross a hyperosmotic barrier presenting the threat of desiccation to reach a source of food odor. We identified a specific interneuron that controls this decision via top-down extrasynaptic aminergic potentiation of the primary osmosensory neurons to increase their sensitivity to the barrier. We also establish that food deprivation increases the worm's willingness to cross the dangerous barrier by suppressing this pathway. These studies reveal a potentially general neural circuit architecture for internal state control of threat-reward decision making.


Subject(s)
Decision Making/physiology , Hunger/physiology , Interneurons/physiology , Animals , Autocrine Communication/physiology , Caenorhabditis elegans , Feedback , Models, Neurological , Nerve Net , Neurons/physiology , Neuropeptides/metabolism , Reward
9.
Nanotechnology ; 27(41): 415402, 2016 Oct 14.
Article in English | MEDLINE | ID: mdl-27595193

ABSTRACT

Yttria-stabilized zirconia (YSZ) thin film electrolyte deposited by plasma enhanced atomic layer deposition (PEALD) was investigated. PEALD YSZ-based bi-layered thin film electrolyte was employed for thin film solid oxide fuel cells on nanoporous anodic aluminum oxide substrates, whose electrochemical performance was compared to the cell with sputtered YSZ-based electrolyte. The cell with PEALD YSZ electrolyte showed higher open circuit voltage (OCV) of 1.0 V and peak power density of 182 mW cm(-2) at 450 °C compared to the one with sputtered YSZ electrolyte(0.88 V(OCV), 70 mW cm(-2)(peak power density)). High OCV and high power density of the cell with PEALD YSZ-based electrolyte is due to the reduction in ohmic and activation losses as well as the gas and electrical current tightness.

10.
Nanotechnology ; 27(21): 215302, 2016 May 27.
Article in English | MEDLINE | ID: mdl-27087196

ABSTRACT

Broadband optical antireflective arrays of sub-wavelength structures were fabricated on silicon substrates using colloidal nanosphere lithography in conjunction with reactive ion etching. The morphology of the nanostructures, including the shape, base diameter and height, was precisely controlled by modifying the conventional process of nanosphere lithography. We investigated their effects on the optical characteristics based on experimentally measured reflectance performance. The Si nanostructure arrays demonstrated optical antireflection performance with an average reflectance of about 1% across the spectral range from 300 to 800 nm, i.e. near-ultraviolet to visible wavelengths. This fabrication method can be used to create a large surface area and offers a promising approach for antireflective applications.

11.
Int Sch Res Notices ; 2014: 637295, 2014.
Article in English | MEDLINE | ID: mdl-27419207

ABSTRACT

Since the discovery that conjugation of ubiquitin to proteins can drive proteolytic degradation, ubiquitination has been shown to perform a diverse range of functions in the cell. It plays an important role in endocytosis, signal transduction, trafficking of vesicles inside the cell, and even DNA repair. The process of ubiquitination-mediated control has turned out to be remarkably complex, involving a diverse array of proteins and many levels of control. This review focuses on a family of structurally related E3 ligases termed the membrane-associated RING-CH (MARCH) ubiquitin ligases, which were originally discovered as structural homologs to the virals E3s, K3, and K5 from Kaposi's sarcoma-associated herpesvirus (KSHV). These proteins contain a catalytic RING-CH finger and are typically membrane-bound, with some having up to 14 putative transmembrane domains. Despite several lines of evidence showing that the MARCH proteins play a complex and essential role in several cellular processes, this family remains understudied.

12.
J Nanosci Nanotechnol ; 14(12): 9294-9, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25971054

ABSTRACT

The effects of a post-annealing treatment on the performance of low-temperature solid oxide fuel cells (LT-SOFCs) were investigated. Nickel oxide-samarium doped ceria (NiO-SDC) anodes and yttria stabilized zirconia (YSZ) electrolytes were deposited on anodized aluminum oxide (AAO) membranes by RF sputtering and DC reactive sputtering, respectively. The half-cell of YSZ/NiO-SDC was then heat-treated at 600 degrees C for 10 h, and a porous platinum (Pt) cathode was deposited on the annealed YSZ/NiO-SDC structure by DC magnetron sputtering. Electrochemical impedance spectroscopy (EIS) analysis revealed a significant decrease in the ohmic resistance and a slight increase in the cathodic impedance. Such a result may be attributed to the increased grain size and enhanced crystallinity of the YSZ electrolyte after the heat treatment. The maximum power density observed for the heat-treated cell was 35 mW/cm2 at 450 degrees C, more than three times higher than the 10 mW/cm2 value obtained for the as-deposited cell.

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