Dinitrosyl Iron Complex-Derived Nanosized Zerovalent Iron (NZVI) as a Template for the Fe-Co Cracked NZVI: An Electrocatalyst for the Oxygen Evolution Reaction.

Nanosized zerovalent iron (NZVI) Fe@Fe3O4 with a core-shell structure derived from photocatalytic MeOH aqueous solution of dinitrosyl iron complex (DNIC) [(N3MDA)Fe(NO)2] (N3MDA = N,N-dimethyl-2-(((1-methyl-1H-imidazole-2-yl)methylene)amino)ethane-1-amine) (1-N3MDA), eosin Y, and triethylamine (TEA) is demonstrated. The NZVI Fe@Fe3O4 core shows a high percentage of zerovalent iron (Fe0 %) and is stabilized by a hydrophobic organic support formed through the photodegradation of eosin Y hybridized with the N3MDA ligand. In addition to its well-known reductive properties in wastewater treatment and groundwater remediation, NZVI demonstrates the ability to form heterostructures when it interacts with metal ions. In this research, Co2+ is employed as a model contaminant and reacted with NZVI Fe@Fe3O4 to result in the formation of a distinct Fe-Co heterostructure, cracked NZVI (CNZVI). The slight difference in the standard redox potentials between Fe2+ and Co2+, the magnetic properties of Co2+, and the absence of surface hydroxides of Fe@Fe3O4 enable NZVI to mildly reduce Co2+ and facilitate Co2+ penetration into the iron core. Taking advantage of the well-dispersed nature of CNZVI on an organic support, the reduction in particle size due to Co2+ penetration, and Fe-Co synergism, CNZVI is employed as a catalyst in the alkaline oxygen evolution reaction (OER). Remarkably, CNZVI exhibits a highly efficient OER performance, surpassing the benchmark IrO2 catalyst. These findings show the potential of using NZVI as a template for synthesizing highly efficient OER catalysts. Moreover, the study demonstrates the possibility of repurposing waste materials from water treatment as valuable resources for catalytic energy conversion, particularly in water oxidation processes.

One-Pot Photosynthesis of Cubic Fe@Fe3O4 Core-Shell Nanoparticle Well-Dispersed in N-Doping Carbonaceous Polymer Using a Molecular Dinitrosyl Iron Precursor.

Nanoscale zerovalent iron (NZVI) features potential application to biomedicine, (electro-/photo)catalysis, and environmental remediation. However, multiple-synthetic steps and limited ZVI content prompt the development of a novel strategy for efficient preparation of NZVI composites. Herein, a dinitrosyl iron complex [(N3MDA)Fe(NO)2] (1-N3MDA) was explored as a molecular precursor for one-pot photosynthesis of a cubic Fe@Fe3O4 core-shell nanoparticle (ZVI% = 60%) well-dispersed in an N-doping carbonaceous polymer (NZVI@NC). Upon photolysis of 1-N3MDA, photosensitizer Eosin Y, and sacrificial reductant TEA, the α-diimine N3MDA and noninnocent NO ligands (1) enable the slow reduction of 1-N3MDA into an unstable [(N3MDA)Fe(NO)2]- species, (2) serve as a capping reagent for controlled nucleation of zerovalent Fe atom into Fe nanoparticle, and (3) promote the polymerization of degraded Eosin Y with N3MDA yielding an N-doping carbonaceous matrix in NZVI@NC. This discovery of a one-pot photosynthetic process for NZVI@NC inspires continued efforts on its application to photolytic water splitting and ferroptotic chemotherapy in the near future.

Communication Network Architectures for Driver Assistance Systems.

Autonomous Driver Assistance Systems (ADAS) are of increasing importance to warn vehicle drivers of potential dangerous situations. In this paper, we propose one system to warn drivers of the presence of pedestrians crossing the road. The considered ADAS adopts a CNN-based pedestrian detector (PD) using the images captured from a local camera and to generate alarms. Warning messages are then forwarded to vehicle drivers approaching the crossroad by means of a communication infrastructure using public radio networks and/or local area wireless technologies. Three possible communication architectures for ADAS are presented and analyzed in this paper. One format for the alert message is also presented. Performance of the PDs are analyzed in terms of accuracy, precision, and recall. Results show that the accuracy of the PD varies from 70% to 100% depending on the resolution of the videos. The effectiveness of each of the considered communication solutions for ADAS is evaluated in terms of the time required to forward the alert message to drivers. The overall latency including the PD processing and the alert communication time is then used to define the vehicle braking curve, which is required to avoid collision with the pedestrian at the crossroad.

Diffusion of glycophorin A in human erythrocytes.

Several lines of evidence suggest that glycophorin A (GPA) interacts with band 3 in human erythrocyte membranes including: i) the existence of an epitope shared between band 3 and GPA in the Wright b blood group antigen, ii) the fact that antibodies to GPA inhibit the diffusion of band 3, iii) the observation that expression of GPA facilitates trafficking of band 3 from the endoplasmic reticulum to the plasma membrane, and iv) the observation that GPA is diminished in band 3 null erythrocytes. Surprisingly, there is also evidence that GPA does not interact with band 3, including data showing that: i) band 3 diffusion increases upon erythrocyte deoxygenation whereas GPA diffusion does not, ii) band 3 diffusion is greatly restricted in erythrocytes containing the Southeast Asian Ovalocytosis mutation whereas GPA diffusion is not, and iii) most anti-GPA or anti-band 3 antibodies do not co-immunoprecipitate both proteins. To try to resolve these apparently conflicting observations, we have selectively labeled band 3 and GPA with fluorescent quantum dots in intact erythrocytes and followed their diffusion by single particle tracking. We report here that band 3 and GPA display somewhat similar macroscopic and microscopic diffusion coefficients in unmodified cells, however perturbations of band 3 diffusion do not cause perturbations of GPA diffusion. Taken together the collective data to date suggest that while weak interactions between GPA and band 3 undoubtedly exist, GPA and band 3 must have separate interactions in the membrane that control their lateral mobility.

A rapid and accurate method to detect active small bowel gastrointestinal bleeding on video capsule endoscopy.

BACKGROUND: Video capsule endoscopy (VCE) is indicated to evaluate for suspected small bowel bleeding, but "standard view" (SV) evaluation is time-consuming. Rapid Reader 6.0 software (Given Imaging, Duluth GA) contains two computer algorithmic systems: (1) "Quickview" (QV) which automatically skips similar images and (2) a pixel analysis program that identifies suspected blood (SBI). Combining the two modalities (QV + SBI) may provide a faster modality to assess for active small bowel bleeding. AIMS: This study was designed to assess the accuracy of QV + SBI for small bowel bleeding compared to SV findings. METHODS: This is a retrospective, case-control study at a single tertiary care referral hospital including all patients with VCE performed for suspected small bowel bleeding from 4/2007 to 3/2011. All studies were previously read using SV by one of two experienced faculty (CS, DR). The primary outcome was diagnostic accuracy of QV + SBI in assessing for active small bowel bleeding compared to SV. RESULTS: A total of 116 VCE were included, 28 with active small bowel bleeding identified by original SV. Using QV + SBI, all 28 VCEs with active small bowel bleeding were identified. The sensitivity of QV + SBI to detect active bleeding was 100%, while the specificity was 93-94%. The mean time to identify landmarks and read the entire study was 3 min 20 s. CONCLUSIONS: The QV + SBI reading format of VCE is an efficient, highly sensitive modality to assess for potential small bowel bleeding.

V(H)H (nanobody) directed against human glycophorin A: a tool for autologous red cell agglutination assays.

The preparation of a V(H)H (nanobody) named IH4 that recognizes human glycophorin A (GPA) is described. IH4 was isolated by screening a library prepared from the lymphocytes of a dromedary immunized by human blood transfusion. Phage display and panning against GPA as the immobilized antigen allowed isolating this V(H)H. IH4, representing 67% of the retrieved V(H)H sequences, was expressed as a soluble correctly folded protein in SHuffle Escherichia coli cells, routinely yielding approximately 100 mg/L fermentation medium. Because IH4 recognizes GPA independently of the blood group antigens, it recognizes red cells of all humans with the possible exception of those with some extremely rare genetic background. The targeted linear epitope comprises the GPA Y52PPE55 sequence. Based on surface plasmon resonance results, the dissociation constant of the IH4-GPA equilibrium is 33 nM. IH4 is a stable protein with a transition melting temperature of 75.8 °C (measured by differential scanning calorimetry). As proof of concept, we fused HIV p24 to IH4 and used the purified construct expressed in E. coli to show that IH4 was amenable to the preparation of autologous erythrocyte agglutination reagents: reconstituted blood prepared with serum from an HIV-positive patient was readily agglutinated by the addition of the bifunctional reagent.

Reversible gastroparesis: functional documentation of celiac axis compression syndrome and postoperative improvement.

Celiac axis compression syndrome has generated much controversy since its original description in 1963. The main symptoms are postprandial epigastric abdominal pain, regurgitation of undigested food, and weight loss, all of which are caused by gastric ischemia from impingement of the celiac axis by the median arcuate ligament of the diaphragm. These symptoms are seen in other common disorders such as chronic mesenteric ischemia and gastroparesis. This makes the diagnosis of celiac axis compression syndrome a true challenge for the clinician. We present data on three patients successfully treated. The pre- and postoperative studies clearly demonstrate a resolution of the condition. The duplex ultrasound images clearly show variable compression on the celiac axis. The angiogram presented shows a classic image of the disease. A review of the data has enabled us to develop an algorithm for the diagnosis of this disease.

Nonsteroidal anti-inflammatory drugs and inflammatory bowel disease: pathophysiology and clinical associations.

Nonsteroidal anti-inflammatory drugs (NSAIDs) produce significant gastrointestinal (GI) adverse events. Laboratory and clinical studies suggest that NSAIDs have the potential to trigger the onset or relapse of inflammatory bowel disease. In this review, the currently available information on the mechanism of action of NSAID injury of the GI tract and the pathophysiology of GI effects of NSAIDs, including immune dysregulation will be assessed. A detailed description of NSAID effects on individual GI organs will be discussed. This is followed by a MEDLINE review of clinical literature on the relationship between NSAID ingestion and the development and worsening of inflammatory bowel disease.