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1.
Entropy (Basel) ; 20(12)2018 Dec 17.
Article in English | MEDLINE | ID: mdl-33266705

ABSTRACT

The processing and analyzing of multimedia data has become a popular research topic due to the evolution of deep learning. Deep learning has played an important role in addressing many challenging problems, such as computer vision, image recognition, and image detection, which can be useful in many real-world applications. In this study, we analyzed visual features of images to detect advertising images from scanned images of various magazines. The aim is to identify key features of advertising images and to apply them to real-world application. The proposed work will eventually help improve marketing strategies, which requires the classification of advertising images from magazines. We employed convolutional neural networks to classify scanned images as either advertisements or non-advertisements (i.e., articles). The results show that the proposed approach outperforms other classifiers and the related work in terms of accuracy.

2.
J Fam Commun ; 17: 15-32, 2017.
Article in English | MEDLINE | ID: mdl-29056872

ABSTRACT

This current study identifies distinct parent prevention communication profiles and examines whether youth with different parental communication profiles have varying substance use trajectories over time. Eleven schools in two rural school districts in the Midwestern United States were selected, and 784 students were surveyed at three time points from the beginning of 7th grade to the end of 8th grade. A series of latent profile analyses were performed to identify discrete profiles/subgroups of substance-specific prevention communication (SSPC). The results revealed a 4-profile model of SSPC: Active-Open, Passive-Open, Active-Silent, and Passive-Silent. A growth curve model revealed different rates of lifetime substance use depending on the youth's SSPC profile. These findings have implications for parenting interventions and tailoring messages for parents to fit specific SSPC profiles.

3.
Prev Sci ; 17(2): 188-98, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26300049

ABSTRACT

Mexican-heritage youth are members of the fastest growing minority group and are at particular risk for substance use including alcohol consumption. Youth face numerous risk factors including positive descriptions of substance use on media and peer offers that are potentially ameliorated by parental anti-substance use socialization efforts. Guided by primary socialization theory and the theory of planned behavior, the present study posited eight research questions to identify discrete subgroups/patterns of Mexican-heritage youth alcohol use behavior and parental influence on youth outcomes. Longitudinal survey data (n = 1147) from youth in 29 public schools located in Phoenix, Arizona, were collected over 3 years. Latent class and transition analyses identified four discrete subgroups characterized by response patterns of alcohol use behaviors and perceptions in Mexican-heritage youth: (1) non-drinker, (2) potential drinker, (3) experimenter, and (4) regular drinker. Targeted parent-child communication about alcohol and parental monitoring were found to be significant predictors for youth alcohol use. Research implications and future directions are suggested.


Subject(s)
Alcohol Drinking , Alcoholism/prevention & control , Parent-Child Relations , Adolescent , Arizona , Child , Communication , Female , Health Surveys , Humans , Longitudinal Studies , Male , Mexican Americans
4.
Diagn Ther Endosc ; 2012: 418037, 2012.
Article in English | MEDLINE | ID: mdl-23197930

ABSTRACT

Wireless capsule endoscopy (WCE) enables a physician to diagnose a patient's digestive system without surgical procedures. However, it takes 1-2 hours for a gastroenterologist to examine the video. To speed up the review process, a number of analysis techniques based on machine vision have been proposed by computer science researchers. In order to train a machine to understand the semantics of an image, the image contents need to be translated into numerical form first. The numerical form of the image is known as image abstraction. The process of selecting relevant image features is often determined by the modality of medical images and the nature of the diagnoses. For example, there are radiographic projection-based images (e.g., X-rays and PET scans), tomography-based images (e.g., MRT and CT scans), and photography-based images (e.g., endoscopy, dermatology, and microscopic histology). Each modality imposes unique image-dependent restrictions for automatic and medically meaningful image abstraction processes. In this paper, we review the current development of machine-vision-based analysis of WCE video, focusing on the research that identifies specific gastrointestinal (GI) pathology and methods of shot boundary detection.

5.
J Am Chem Soc ; 134(33): 13871-80, 2012 Aug 22.
Article in English | MEDLINE | ID: mdl-22827631

ABSTRACT

Bent-shaped rigid-core molecules with flexible chiral dendrons grafted to the outer side of the bend were synthesized and characterized by circular dichroism, differential scanning calorimetry, X-ray scatterings, and transmission electron microscopy in solution and the solid state. The bent aromatic rods based on hepta- and nonaphenylene with nitrile groups at both ends self-assemble into well-ordered hollow tubular structures in aqueous solution, while the bent rod based on heptaphenylene without nitrile groups showed no apparent aggregations in aqueous solution. In the solid state, the rigid-flexible molecules based on heptaphenylene rod without the nitrile group self-assemble into a 2D oblique columnar structure with the columnar cross-section containing two interlocked molecules. Remarkably, the rigid flexible molecules based on hepta-, nona-, and undecaphenylene with nitrile groups self-assemble into a hexagonal columnar structure with weak 3D order. A model of vesicular channel structure is proposed based on small- and wide-angle X-ray diffraction on oriented fibers, density measurement, reconstruction and simulation of electron density maps, and molecular dynamics simulation. In contrast to the hollow tubular structure found in solution, in the solid both the outside and the interior of the columns are filled by the pendant aliphatic coils. Filling of the interior of these vesicular channels is made possible by some bent rod molecules turning their obtuse apex inward. One in 7, 2 in 8, and 4 in 10 molecules are thus inverted in a column slice in compounds with hepta-, nona-, and undecaphenylene cores, respectively. These are new examples of vesicular double-segregated columnar structures recently discovered in some dendrons.


Subject(s)
Dendrimers/chemistry , Hydrocarbons, Aromatic/chemistry , Polyethylene Glycols/chemistry , Circular Dichroism , Dendrimers/chemical synthesis , Hydrocarbons, Aromatic/chemical synthesis , Microscopy, Electron, Transmission , Models, Molecular , Phase Transition , Polyethylene Glycols/chemical synthesis , X-Ray Diffraction
6.
Chem Commun (Camb) ; 48(28): 3418-20, 2012 Apr 07.
Article in English | MEDLINE | ID: mdl-22314373

ABSTRACT

In contrast to the known perpendicular ordering of conventional PS-b-PLA thin films, branched (PS)(2)-b-PLA thin films showed two different parallel orientations whose locations are strongly dependent upon film thickness.

8.
Artif Organs ; 34(1): 37-45, 2010 Jan.
Article in English | MEDLINE | ID: mdl-19821814

ABSTRACT

The immunogenicity of lyophilized porcine cornea is unknown. The purpose of this study was to examine the possibility of using lyophilized porcine cornea as a substrate for ocular surface reconstruction. A porcine cornea stromal button was freeze-dried and vacuum-packed. Lyophilized and fresh porcine corneas were examined histologically, and then implanted into intrastromal pockets in live rat corneas. Cytokine concentrations in plasma and protein extracts from the corneal buttons of rats were measured using the fluorokine multianalyte profiling assay, and histologic examination was performed. Immunoreactivity to the alpha-gal epitope was not found in lyophilized porcine corneas, whereas it was found in several keratocytes in fresh porcine corneas. The median survival time of rat corneas receiving lyophilized porcine transplants was 28.0 days, significantly longer than the 14.0-day survival of rat corneas that received fresh porcine transplants (P < 0.05). CD45RO(+) and CD68(+) cells were observed in rejected corneas, and interleukin-2 and interferon-gamma were elevated in rat plasma and corneal tissue. The lyophilized porcine corneal stroma, which is devoid of alpha-gal epitope, is less antigenic, and may be a useful biomaterial for ocular surface reconstruction and corneal collagen supplementation.


Subject(s)
Cornea/immunology , Corneal Transplantation , Graft Rejection/immunology , Animals , Cytokines/blood , Freeze Drying , Graft Rejection/prevention & control , Immunohistochemistry , Rats , Rats, Sprague-Dawley , Swine , Transplantation, Heterologous
10.
Angew Chem Int Ed Engl ; 48(9): 1664-8, 2009.
Article in English | MEDLINE | ID: mdl-19072811

ABSTRACT

On a roll: Attachment of flexible coils to the middle of a rigid rod generates T-shaped rod-coil molecules that self-assemble into layers that roll up to form filled cylindrical and hollow tubular scrolls, depending on the coil length, in the solid state (see picture); the rods are arranged parallel to the layer plane.


Subject(s)
Liquid Crystals/chemistry , Nanostructures/chemistry , Microscopy, Electron, Transmission , Molecular Conformation , Surface-Active Agents/chemistry , Thermodynamics
11.
J Am Chem Soc ; 130(48): 16142-3, 2008 Dec 03.
Article in English | MEDLINE | ID: mdl-19006309

ABSTRACT

Binding of AuCl(4)(-) to amine groups tethered to the interior of a 2 nm siloxane nanocage was determined in solutions containing various concentrations of acid. The mode of binding was inferred from EXAFS and UV-vis spectra to be by ligand exchange of amine for chloride, which implies that the amines remain unprotonated. Cyclic voltammetry confirmed that the Au complexes bind to the nanocage interior and established a 1:1 relationship between bound Au complex and amine groups. The results suggested a 5-7 pH unit shift in the protonation constant of the interior amines relative to free amines in solution.

12.
J Am Chem Soc ; 130(44): 14448-9, 2008 Nov 05.
Article in English | MEDLINE | ID: mdl-18842040

ABSTRACT

We have demonstrated that the rod segments with lateral dendritic chains self-assemble into unique stepped strips in which the rods are aligned parallel to the strip long axis. This unique organization of the rod segments arises from a balance between the energetic gain of a parallel arrangement of the rods and the resulting entropic penalty associated with stretching of the lateral flexible chains.

13.
J Am Chem Soc ; 130(22): 7139-47, 2008 Jun 04.
Article in English | MEDLINE | ID: mdl-18454533

ABSTRACT

We prepared a series of amphiphilic dendron coils (1-3) containing aliphatic polyether dendrons with octadecyl peripheries and a poly(ethylene oxide) (PEO) coil (DP = 44). The molecular design in this study is focused on the variation of dendron generation (from first to third) with a fixed linear coil, upon which the thermal and self-assembling behavior of the dendron coils was investigated in the bulk. All the dendron coils exhibit two crystalline phases designated as k1 (both crystalline octadecyl chains and PEO) and k2 states (crystalline octadecyl chains and molten PEO). Crystallinities for both octadecyl peripheries and the PEO decrease as generation increases. In particular, the dendron coil (3) containing third generation shows a drastic reduction of the PEO crystallinity, which is attributed to the considerable chain folding and plasticization effects by the largest hydrophilic dendritic core segment. All the crystalline phases are bilayered lamellar morphologies. On going from k1 to k2, the periodic lamellar thickness decreases in the dendron coil (1) with first generation, but interestingly increases in 3. After melting of octadecyl peripheries, 1 shows no mesophase (i.e., liquid crystalline phase). Additionally, dendron coil 2 (3) displays a network cubic mesophase with Ia3d symmetry (micellar cubic with Pm3n) which is transformed into a lamellar (hexagonal columnar) mesophase upon heating. Remarkably, the temperature-dependent mesomorphic behavior in 2 and 3 is a completely reverse pattern in comparison with conventional linear-linear block copolymers. The unusual bulk morphological phenomena in the crystalline and liquid crystalline phases can be elucidated by the dendron coil architecture and the associated coil conformational energy.

14.
Article in English | MEDLINE | ID: mdl-17942346

ABSTRACT

The aim of this clinical report is to describe the unusual root canal anatomy of 2 maxillary second molars with 2 separated palatal roots and the endodontic treatment procedures for those teeth. In these presented cases, microscopy was useful to identify distopalatal orifice. Radiographic interpretation was difficult owing to the overlap of the buccal and secondary palatal roots.


Subject(s)
Dental Caries/therapy , Dental Pulp Cavity/abnormalities , Molar/abnormalities , Root Canal Therapy/methods , Tooth Root/abnormalities , Adult , Dental Pulp Cavity/diagnostic imaging , Female , Humans , Microscopy/methods , Middle Aged , Molar/diagnostic imaging , Radiography , Retreatment/methods , Tooth Root/diagnostic imaging
16.
Med Image Anal ; 11(2): 110-27, 2007 Apr.
Article in English | MEDLINE | ID: mdl-17329146

ABSTRACT

Advances in video technology allow inspection, diagnosis and treatment of the inside of the human body without or with very small scars. Flexible endoscopes are used to inspect the esophagus, stomach, small bowel, colon, and airways, whereas rigid endoscopes are used for a variety of minimal invasive surgeries (i.e., laparoscopy, arthroscopy, endoscopic neurosurgery). These endoscopes come in various sizes, but all have a tiny video camera at the tip. During an endoscopic procedure, the tiny video camera generates a video signal of the interior of the human organ, which is displayed on a monitor for real-time analysis by the physician. However, many out-of-focus frames are present in endoscopy videos because current endoscopes are equipped with a single, wide-angle lens that cannot be focused. We need to distinguish the out-of-focus frames from the in-focus frames to utilize the information of the out-of-focus and/or the in-focus frames for further automatic or semi-automatic computer-aided diagnosis (CAD). This classification can reduce the number of images to be viewed by a physician and to be analyzed by a CAD system. We call an out-of-focus frame a non-informative frame and an in-focus frame an informative frame. The out-of-focus frames have characteristics that are different from those of in-focus frames. In this paper, we propose two new techniques (edge-based and clustering-based) to classify video frames into two classes, informative and non-informative frames. However, because intensive specular reflections reduce the accuracy of the classification we also propose a specular reflection detection technique, and use the detected specular reflection information to increase the accuracy of informative frame classification. Our experimental studies indicate that precision, sensitivity, specificity, and accuracy for the specular reflection detection technique and the two informative frame classification techniques are greater than 90% and 95%, respectively.


Subject(s)
Endoscopy/methods , Video Recording/methods , Diagnosis, Computer-Assisted , Fourier Analysis , Humans , Image Processing, Computer-Assisted , Sensitivity and Specificity
17.
Artif Organs ; 30(6): 424-31, 2006 Jun.
Article in English | MEDLINE | ID: mdl-16734593

ABSTRACT

The purpose of this article was to evaluate the graft efficacy of reconstructed corneal layer, composed of autologous corneal epithelium and fibroblasts on a lyophilized amniotic membrane (LAM), in a severely alkali-burned corneal model. After biopsy specimens were obtained from the left eyes of 24 rabbits, the corneal epithelial cells and fibroblasts were expanded in vitro and the corneal layer was reconstructed on LAM. Thirty-six eyes of rabbits underwent alkali burn (1 N NaOH, 30 s) to create a limbal deficiency and a deeply damaged corneal stroma. Four weeks later, group 1 underwent a graft of the reconstructed corneal layer composed of autologous corneal epithelium and fibroblasts on LAM. Group 2 was transplanted with a graft of the reconstructed autologous corneal epithelium, and group 3 served as a control without surgery. Wound healing and stabilization of the ocular surfaces occurred much faster in group 1 than in groups 2 and 3. The eyes in group 3 revealed typical limbal deficiencies with conjuctivalization and persistent corneal epithelial defects. However, the corneas in group 1 developed only mild peripheral neovascularization. Immunohistochemical staining in group 1 demonstrated that p63, cytokeratin 3, E-cadherin, transforming growth factor (TGF)-beta1, and collagen IV were expressed strongly in the corneal epithelium and basement membrane. On the basis of these results, transplantation of the reconstructed corneal layer, composed of autologous corneal epithelium and fibroblasts on LAM, partially accelerated the recovery of the alkali-injured rabbit ocular surface, and might be useful therapeutically for the treatment of patients with severely damaged cornea.


Subject(s)
Amnion , Burns, Chemical/therapy , Corneal Injuries , Corneal Transplantation/methods , Epithelium, Corneal/transplantation , Eye Burns/therapy , Animals , Bioartificial Organs , Cell Differentiation , Cornea/cytology , Fibroblasts/cytology , Fibroblasts/physiology , Freeze Drying , Humans , Rabbits
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