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1.
J Phys Chem Lett ; 14(51): 11768-11773, 2023 Dec 28.
Article in English | MEDLINE | ID: mdl-38126300

ABSTRACT

The recent synthesis of monolayer fullerene networks (Hou, L., et al. Nature 2022, 606, 507) provides new opportunities for photovoltaics and photocatalysis because of their versatile crystal structures for further tailoring of electronic, optical, and chemical function. To shed light on the structural aspects of the photocatalytic water splitting performance of fullerene nanomaterials, we compare the photocatalytic properties of individual polymeric fullerene chains and monolayer fullerene networks from first-principles calculations. We find that the photocatalytic efficiency can be further optimized by reducing the dimensionality from two-dimensional (2D) to one-dimensional (1D). The conduction band edge of the polymeric C60 chain provides an external potential for the hydrogen reduction reaction much higher than that of its monolayer counterparts over a wider range of pH values, and there are 2 times more surface active sites in the 1D chain than in the 2D networks from a thermodynamic perspective. These observations identify the 1D fullerene polymer as a more promising candidate as a photocatalyst for the hydrogen evolution reaction in comparison to monolayer fullerene networks.

2.
JPGN Rep ; 4(4): e384, 2023 Nov.
Article in English | MEDLINE | ID: mdl-38034444

ABSTRACT

Currently, there exists a scarcity of suitable nutrition training resources for the primary care physician (PCP) and a paucity of educational materials for pediatric residency programs. Barriers to nutritional education include: a lack of well-defined competencies, a dearth of centralized resources for nutritional education, and a reliance on didactic teaching methodology. Because PCPs often cite a lack of confidence as a primary reason for not providing nutritional counseling, we created an interactive 3-pronged nutritional curriculum for pediatric residents with the aim of increasing their confidence to provide nutritional counseling to patients. This curriculum included an in-person visit to a local supermarket, an online, interactive case during the resident's continuity clinic, and an interactive lecture. There was a statistically significant change in pediatric residents' confidence to manage issues of outpatient nutrition management. We find this particularly relevant as increasing physician confidence is key to increasing nutritional counseling in a clinical setting.

3.
Am J Perinatol ; 2023 Apr 18.
Article in English | MEDLINE | ID: mdl-37072015

ABSTRACT

OBJECTIVE: Monitoring heart rate (HR) and oxygen saturation (SpO2) in infants is essential in the neonatal intensive care unit. Wireless pulse oximeter technology has been advancing but with limited accuracy data on preterm infants. This observational study compared HR and SpO2 of the wireless Owlet Smart Sock 3 (OSS3) to the wired Masimo SET (Masimo) pulse oximeter in preterm or <2.5 kg infants. STUDY DESIGN: Twenty-eight eligible infants were enrolled. They weighed between 1.7 and 2.5 kg and were without anomalies or medical instability. OSS3 and Masimo simultaneously monitored HR and SpO2 for 60 minutes. The data were aligned by time epoch and filtered for poor tracings. The agreement was compared using the Pearson's correlation coefficient, the Bland-Altman method, average root mean square (ARMS), and prevalence and bias adjusted kappa (PABAK) analyses. RESULTS: Two infants' data were excluded due to motion artifacts or device failures. The corrected gestational age and current weights were 35 ± 3 weeks and 2.0 ± 0.2 kg (mean ± standard deviation), respectively. Over 21 hours of data showed that HR was strongly correlated between the two devices (r = 0.98, p < 0.001), with a difference of -1.3 beats per minute (bpm) and the limit of agreement (LOA) -6.3 to 3.4 bpm based on the Bland-Altman method. SpO2 was positively correlated between the two devices (r = 0.71, p < 0.001) with a SpO2 bias of 0.3% (LOA: -4.6 to 4.5%). The estimated ARMS of OSS3 compared with Masimo was 2.3% for SpO2 in the 70 to 100% range. The precision decreased with lower SpO2. A strong agreement (PABAK = 0.94) was between the two devices on whether SpO2 was above or below 90%. CONCLUSION: OSS3 provided comparable HR and SpO2 accuracy to Masimo in preterm or <2.5 kg infants. Motion artifacts, lack of arterial blood gas comparisons, and lack of racial and ethnic diversity are the study limitations. More OSS3 data on the Lower HR and SpO2 ranges were needed before implementing inpatient use. KEY POINTS: · Pulse oximeters are vital for monitoring preterm infants' HR and SpO2 levels.. · Limited data exist on the accuracy of the wireless OSS3 on preterm infants.. · This observational study found that the OSS3 is comparable to the Masimo SET in measuring HR and SpO2 in preterm or <2.5 kg infants..

4.
Nutr Clin Pract ; 35(5): 911-918, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32578899

ABSTRACT

OBJECTIVES: Despite frequent placement of pediatric laparoscopic gastrostomy tubes (GTs), no rigorous evaluation of initial feeding and advancement regimens exists. Therefore, the aim of this study was to determine whether early enteral feeding after GT placement is associated with increased symptoms, procedural complications, or length of stay (LOS). METHODS: In this retrospective cohort study, the records of all patients at a tertiary care pediatric hospital who had gastrostomy placement were reviewed. Only patients fed exclusively via gastrostomy were included. Feeding was monitored starting with the first postoperative feed and subsequently in 24-hour increments. Adverse events were recorded based on clinical documentation. RESULTS: A total of 480 patients met inclusion criteria. Patients who started feeds between 24 and 36 hours had a shorter LOS compared with those who started at 36-48 hours (P = .0072) or >48 hours (P < .0001). Patients requiring ≥60 hours to reach goal feeds had significantly longer LOS than the other groups. There was no difference in the distribution of the LOS based on percentage of goal feeds initiated. Patients who required ≥60 hours to attain goal feeds had the most feeding complications. CONCLUSIONS: More aggressive feeding advancement and earlier initiation of feeds were associated with decreased LOS without an associated increase in adverse clinical events.


Subject(s)
Enteral Nutrition/methods , Gastrostomy/methods , Intubation, Gastrointestinal/methods , Laparoscopy/methods , Length of Stay/statistics & numerical data , Child, Preschool , Enteral Nutrition/adverse effects , Female , Gastrostomy/adverse effects , Humans , Infant , Intubation, Gastrointestinal/adverse effects , Laparoscopy/adverse effects , Male , Postoperative Complications/epidemiology , Postoperative Complications/etiology , Retrospective Studies , Time Factors , Treatment Outcome
5.
Small ; 14(12): e1703515, 2018 03.
Article in English | MEDLINE | ID: mdl-29383851

ABSTRACT

Here novel chromogenic photonic crystal sensors based on smart shape memory polymers (SMPs) comprising polyester/polyether-based urethane acrylates blended with tripropylene glycol diacrylate are reported, which exhibit nontraditional all-room-temperature shape memory (SM) effects. Stepwise recovery of the collapsed macropores with 350 nm diameter created by a "cold" programming process leads to easily perceived color changes that can be correlated with the concentrations of swelling analytes in complex, multicomponent nonswelling mixtures. High sensitivity (as low as 10 ppm) and unprecedented measurement range (from 10 ppm to 30 vol%) for analyzing ethanol in octane and gasoline have been demonstrated by leveraging colorimetric sensing in both liquid and gas phases. Proof-of-concept tests for specifically detecting ethanol in consumer medical and healthcare products have also been demonstrated. These sensors are inexpensive, reusable, durable, and readily deployable with mobile platforms for quantitative analysis. Additionally, theoretical modeling of solvent diffusion in macroporous SMPs provides fundamental insights into the mechanisms of nanoscopic SM recovery, which is a topic that has received little examination. These novel sensors are of great technological importance in a wide spectrum of applications ranging from environmental monitoring and workplace hazard identification to threat detection and process/product control in chemical, petroleum, and pharmaceutical industries.

6.
J Neurosci Methods ; 246: 13-21, 2015 May 15.
Article in English | MEDLINE | ID: mdl-25769273

ABSTRACT

BACKGROUND: In the area of connectomics, there is a significant gap between the time required for data acquisition and dense reconstruction of the neural processes contained in the same dataset. Automatic methods are able to eliminate this timing gap, but the state-of-the-art accuracy so far is insufficient for use without user corrections. If completed naively, this process of correction can be tedious and time consuming. NEW METHOD: We present a new semi-automatic method that can be used to perform 3D segmentation of neurites in EM image stacks. It utilizes an automatic method that creates a hierarchical structure for recommended merges of superpixels. The user is then guided through each predicted region to quickly identify errors and establish correct links. RESULTS: We tested our method on three datasets with both novice and expert users. Accuracy and timing were compared with published automatic, semi-automatic, and manual results. COMPARISON WITH EXISTING METHODS: Post-automatic correction methods have also been used in Mishchenko et al. (2010) and Haehn et al. (2014). These methods do not provide navigation or suggestions in the manner we present. Other semi-automatic methods require user input prior to the automatic segmentation such as Jeong et al. (2009) and Cardona et al. (2010) and are inherently different than our method. CONCLUSION: Using this method on the three datasets, novice users achieved accuracy exceeding state-of-the-art automatic results, and expert users achieved accuracy on par with full manual labeling but with a 70% time improvement when compared with other examples in publication.


Subject(s)
Imaging, Three-Dimensional , Microscopy, Electron, Scanning , Neurons/ultrastructure , Pattern Recognition, Automated , Animals , Connectome , Models, Neurological , Neurons/metabolism
7.
Am J Physiol Regul Integr Comp Physiol ; 307(7): R862-8, 2014 Oct 01.
Article in English | MEDLINE | ID: mdl-25080497

ABSTRACT

ATP release from erythrocytes in response to reduced oxygen (O2) tension stimulates local vasodilation, enabling these cells to direct perfusion to areas in skeletal muscle in need of O2. Erythrocytes of humans with type 2 diabetes do not release ATP in response to low O2. Both C-peptide and insulin individually inhibit low O2-induced ATP release from healthy human erythrocytes, yet when coadministered at physiological concentrations and ratios, no inhibition is seen. Here, we determined: that 1) erythrocytes of healthy humans and humans with type 2 diabetes possess a C-peptide receptor (GPR146), 2) the combination of C-peptide and insulin at physiological ratios rescues low O2-induced ATP release from erythrocytes of humans with type 2 diabetes, 3) residual C-peptide levels reported in humans with type 2 diabetes are not adequate to rescue low O2-induced ATP release in the presence of 1 nM insulin, and 4) the effects of C-peptide and insulin are neither altered by increased glucose levels nor explained by changes in erythrocyte deformability. These results suggest that the addition of C-peptide to the treatment regimen for type 2 diabetes could have beneficial effects on tissue oxygenation, which would help to ameliorate the concomitant peripheral vascular disease.


Subject(s)
Adenosine Triphosphate/metabolism , C-Peptide/metabolism , Diabetes Mellitus, Type 2/metabolism , Erythrocytes/metabolism , Insulin/metabolism , Oxygen/metabolism , Cell Separation/methods , Humans , Muscle, Skeletal/metabolism
8.
J Neurosci Methods ; 226: 88-102, 2014 Apr 15.
Article in English | MEDLINE | ID: mdl-24491638

ABSTRACT

The study of neural circuit reconstruction, i.e., connectomics, is a challenging problem in neuroscience. Automated and semi-automated electron microscopy (EM) image analysis can be tremendously helpful for connectomics research. In this paper, we propose a fully automatic approach for intra-section segmentation and inter-section reconstruction of neurons using EM images. A hierarchical merge tree structure is built to represent multiple region hypotheses and supervised classification techniques are used to evaluate their potentials, based on which we resolve the merge tree with consistency constraints to acquire final intra-section segmentation. Then, we use a supervised learning based linking procedure for the inter-section neuron reconstruction. Also, we develop a semi-automatic method that utilizes the intermediate outputs of our automatic algorithm and achieves intra-segmentation with minimal user intervention. The experimental results show that our automatic method can achieve close-to-human intra-segmentation accuracy and state-of-the-art inter-section reconstruction accuracy. We also show that our semi-automatic method can further improve the intra-segmentation accuracy.


Subject(s)
Image Processing, Computer-Assisted/methods , Imaging, Three-Dimensional/methods , Microscopy, Electron/methods , Neurons/ultrastructure , Algorithms , Animals , Artificial Intelligence , Central Nervous System/ultrastructure , Cerebral Cortex/ultrastructure , Drosophila , Electronic Data Processing , Mice , Neuropil/ultrastructure
9.
Proc IEEE Int Symp Biomed Imaging ; 2013: 1304-1307, 2013.
Article in English | MEDLINE | ID: mdl-25143801

ABSTRACT

We introduce a novel method for utilizing user input to sparsely label membranes in electron microscopy images. Using gridlines as guides, the user marks where the guides cross the membrane to generate a sparsely labeled image. We use a best path algorithm to connect each of the sparse membrane labels. The resulting segmentation has a significantly better Rand error than automatic methods while requiring as little as 2% of the image to be labeled.

10.
Proc IEEE Int Symp Biomed Imaging ; 2013: 1457-1460, 2013.
Article in English | MEDLINE | ID: mdl-25143802

ABSTRACT

In connectomics, neuroscientists seek to identify the synaptic connections between neurons. Segmentation of cell membranes using supervised learning algorithms on electron microscopy images of brain tissue is often done to assist in this effort. Here we present a partial differential equation with a novel growth term to improve the results of a supervised learning algorithm. We also introduce a new method for representing the resulting image that allows for a more dynamic thresholding to further improve the result. Using these two processes we are able to close small to medium sized gaps in the cell membrane detection and improve the Rand error by as much as 9% over the initial supervised segmentation.

11.
J Perinatol ; 25(11): 725-30, 2005 Nov.
Article in English | MEDLINE | ID: mdl-16151471

ABSTRACT

OBJECTIVE: Darbepoetin is longer acting and more potent than recombinant erythropoietin (rEpo). In certain situations, preterm neonates might benefit from rEpo, and for such patients darbepoetin would require fewer doses at a lower cost. However, the proper dose and dosing interval have not been established. STUDY DESIGN: We performed a prospective trial in two level III Neonatal Intensive Care Units. Patients <32 weeks gestation at birth, with a birth weight (BW) <1500 g, were eligible for participation if they were >21-days-old and had a hemoglobin (Hgb) concentration

Subject(s)
Anemia, Neonatal/drug therapy , Erythropoietin/analogs & derivatives , Infant, Premature, Diseases/drug therapy , Anemia, Neonatal/blood , Area Under Curve , Biological Availability , Darbepoetin alfa , Erythropoietin/administration & dosage , Erythropoietin/pharmacokinetics , Half-Life , Humans , Infant, Newborn , Infant, Premature , Infant, Premature, Diseases/blood , Infant, Very Low Birth Weight , Pilot Projects , Prospective Studies , Reticulocyte Count
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