A novel method for estimating subresolution porosity from CT images and its application to homogeneity evaluation of porous media.

We propose a new method, i.e., the statistical phase fraction (SPF) method, to estimate the total porosity and spatial distribution of local porosities from subresolution pore-dominated X-ray microtomography images of porous materials. The SPF method assumes that a voxel in a CT image is composed of either a single or a maximum of three pure phases of matter (solid, liquid and air). Gaussian function (GF) fitting is conducted on the basis that the summation of the area of each GF curve is equal to the total area covered by the CT histogram. The volume fraction of each phase corresponding to each GF is calculated based on the mean value of the GF, the area of the GF, and the CT numbers for pure phases. The SPF method is verified on three different types of components containing only air and solid phases, i.e., alumina ceramic and two sintered lunar regolith simulants with relatively homogenous and inhomogeneous microstructures. The estimated porosities of a total of 15 specimens (the total porosity ranges from 0 to 51%) via the SPF method show an average error of 3.11% compared with the ground truth. Spatial distribution of local porosities in the defined representative element volume is investigated for homogeneity evaluation. Results show that the local porosity inhomogeneity in the sintered FJS-1 specimens is more prominent than that in the sintered KLS-1 specimens.

Complementary Driving between 2D Heterostructures and Surface Functionalization for Surpassing Binary Logic Devices.

Recently, for overcoming the fundamental limits of conventional silicon technology, multivalued logic (MVL) circuits based on two-dimensional (2D) materials have received significant attention for reducing the power consumption and the complexity of integrated circuits. Compared with the conventional silicon complementary metal oxide semiconductor technology, new functional heterostructures comprising 2D materials can be readily implemented, owing to their unique inherent electrical properties. Furthermore, their process integration does not pose issues of lattice mismatch at junction interfaces. This facilitates the realization of new functional logic gate circuit configurations. However, the reported three-valued NOT gates (ternary inverters) based on 2D materials require stringent operating conditions and complex fabrication processes to obtain three distinct logic states. Herein, a general structure of MVL devices based on a simple series connection of 2D materials with partial surface functionalization is demonstrated. By arranging three 2D materials exhibiting p-type, ambipolar, and n-type conductivities, ternary inverter circuits can be established based on the complementary driving between 2D heterotransistors. This ternary inverter circuit can be further improved for quaternary inverter circuits by controlling the charge neutral point of partial ambipolar 2D materials using surface functionalization, which is an effective and nondestructive doping method for 2D materials.

Factors Associated with Molar-Incisor Hypomineralization: A Population-Based Case-Control Study.

Purpose: The purpose of this case-control study was to investigate the relationship between molar-incisor hypomineralization (MIH) and pre-, peri-, and postnatal conditions of children and mothers in South Korea. Methods: The Korean Academy of Pediatric Dentistry con- ducted this study to examine factors associated with MIH among six- to 13-year-olds. The European Academy of Pediatric Dentistry criteria and self-administered questionnaires associated with MIH were used. Results: In multivariable logistic regression analysis, the odds ratio (OR) of MIH for children whose mothers used health supplements during pregnancy was 0.65 (P=0.009). Also, children with more than three hours of out- door activities per day tended to have a lower MIH (P=0.03) than did those with zero hours of outdoor activity. Additionally, the OR of MIH for children whose mothers smoked during pregnancy was 2.37 (P=0.019) and the MIH found to be 1.33 times more frequent in children with respiratory infections during the first three years of life (P=0.048). Conclusions: Maternal smoking during pregnancy and child's pediatric respiratory infection suffered within three years after birth are factors associated with the MIH among Korean children. Further study is needed because the prevalence of MIH in children whose mothers taking health supplements (vitamins or folic acid or iron) during pregnancy is low.

Activity of LCB01-0371, a Novel Oxazolidinone, against Mycobacterium abscessus.

Mycobacterium abscessus is a highly pathogenic drug-resistant rapidly growing mycobacterium. In this study, we evaluated the in vitro, intracellular, and in vivo activities of LCB01-0371, a novel and safe oxazolidinone derivative, for the treatment of M. abscessus infection and compared its resistance to that of other oxazolidinone drugs. LCB01-0371 was effective against several M. abscessus strains in vitro and in a macrophage model of infection. In the murine model, a similar efficacy to linezolid was achieved, especially in the lungs. We induced laboratory-generated resistance to LCB01-0371; sequencing analysis revealed mutations in rplC of T424C and G419A and a nucleotide insertion at the 503 position. Furthermore, LCB01-0371 inhibited the growth of amikacin-, cefoxitin-, and clarithromycin-resistant strains. Collectively, our data indicate that LCB01-0371 might represent a promising new class of oxazolidinones with improved safety, which may replace linezolid for the treatment of M. abscessus.

Observation of a Flowing Duct in the Abdominal Wall by Using Nanoparticles.

The primo vascular system (PVS) is being established as a circulatory system that corresponds to acupuncture meridians. There have been two critical questions in making the PVS accepted as a novel liquid flowing system. The first one was directly to show the flow of liquid in PVS and the second one was to explain why it was not observed in the conventional histological study of animal tissues. Flow in the PVS in the abdominal cavity was previously verified by injecting Alcian blue into a primo node. However, the tracing of the dye to other subsystems of the PVS has not been done. In the current work we injected fluorescent nanoparticles (FNPs) into a primo node and traced them along a primo vessel which was inside a fat tissue in the abdominal wall. Linea alba is a white middle line in the abdominal skin of a mammal and a band of fat tissue is located in parallel to the linea alba in the parietal side of the abdominal wall of a rat. In this fat band a primo vessel runs parallel to the prominent blood vessels in the fat band and is located just inside the parietal peritoneum. About the second question on the reason why the PVS was not in conventional histological study the current work provided the answer. Histological analysis with hematoxyline and eosine, Masson's trichrome, and Toluidine blue could not discriminate the primo vessel even when we knew the location of the PVS by the trace of the FNPs. This clearly explains why the PVS is hard to observe in conventional histology: it is not a matter of resolution but the contrast. The PVS has very similar structure to the connective tissues that surround the PVS. In the current work we propose a method to find the PVS: Observation of mast cell distribution with toluidine blue staining and the PN has a high density of mast cells, while the lymph node has low density.

Feasibility of Using Volumetric Contrast-Enhanced Ultrasound with a 3-D Transducer to Evaluate Therapeutic Response after Targeted Therapy in Rabbit Hepatic VX2 Carcinoma.

The aim of this study was to assess the feasibility of using dynamic contrast-enhanced ultrasound (DCE-US) with a 3-D transducer to evaluate therapeutic responses to targeted therapy. Rabbits with hepatic VX2 carcinomas, divided into a treatment group (n = 22, 30 mg/kg/d sorafenib) and a control group (n = 13), were evaluated with DCE-US using 2-D and 3-D transducers and computed tomography (CT) perfusion imaging at baseline and 1 d after the first treatment. Perfusion parameters were collected, and correlations between parameters were analyzed. In the treatment group, both volumetric and 2-D DCE-US perfusion parameters, including peak intensity (33.2 ± 19.9 vs. 16.6 ± 10.7, 63.7 ± 20.0 vs. 30.1 ± 19.8), slope (15.3 ± 12.4 vs. 5.7 ± 4.5, 37.3 ± 20.4 vs. 15.7 ± 13.0) and area under the curve (AUC; 1004.1 ± 560.3 vs. 611.4 ± 421.1, 1332.2 ± 708.3 vs. 670.4 ± 388.3), had significantly decreased 1 d after the first treatment (p = 0.00). In the control group, 2-D DCE-US revealed that peak intensity, time to peak and slope had significantly changed (p < 0.05); however, volumetric DCE-US revealed that peak intensity, time-intensity AUC, AUC during wash-in and AUC during wash-out had significantly changed (p = 0.00). CT perfusion imaging parameters, including blood flow, blood volume and permeability of the capillary vessel surface, had significantly decreased in the treatment group (p = 0.00); however, in the control group, peak intensity and blood volume had significantly increased (p = 0.00). It is feasible to use DCE-US with a 3-D transducer to predict early therapeutic response after targeted therapy because perfusion parameters, including peak intensity, slope and AUC, significantly decreased, which is similar to the trend observed for 2-D DCE-US and CT perfusion imaging parameters.

Korean clinical practice guidelines: otitis media in children.

Acute otitis media (AOM) and otitis media with effusion (OME) are common infections in children, and their diagnosis and treatment have significant impacts on the health of children and the costs of providing national medical care. In 2009, the Korean Otologic Society organized a committee composed of experts in the field of otolaryngology, pediatrics, and family medicine to develop Korean clinical practice guidelines (CPG) for otitis media in children with the goal of meeting regional medical and social needs in Korea. For this purpose, the committee adapted existing guidelines. A comprehensive literature review was carried out primarily from 2004 to 2009 using medical search engines including data from Korea. A draft was written after a national questionnaire survey and several public audits, and it was editorially supervised by senior advisors before publication of the final report. These evidence-based guidelines for the management of otitis media in children provide recommendations to primary practitioners for the diagnosis and treatment of children younger than 15 yr old with uncomplicated AOM and OME. The guidelines include recommendations regarding diagnosis, treatment options, prevention and parent education, medical records, referral, and complementary/alternative medicine for treating pediatric otitis media.

Computerized fetal heart rate monitoring after vibroacoustic stimulation in the anencephalic fetus.

BACKGROUND: To quantify changes in fetal heart rate (FHR) parameters after vibroacoustic stimulation (VAS) and to evaluate the usefulness of VAS testing (VAST) in anencephalic fetuses. Our findings may also help to clarify the route(s) of vibration and sound transmission during VAST. STUDY DESIGN AND SUBJECTS: We obtained the antepartum FHR tracings of 16 anencephalic fetuses, including both the nonstress test (NST) and VAST. Using a computerized monitoring system, HYFM, we determined all FHR parameters from data collected for 10 min before and 10 min after VAS, at successive gestational stages. RESULTS: We observed three false reactive responses at term. The false reactive rate for VAST (3/16) was higher than that for NST (1/16). No FHR parameters increased significantly after VAS except for the number of fetal movements (FM), which increased significantly in all gestational groups (25th-32nd and 33rd-40th weeks). CONCLUSIONS: These findings call attention to an increased probability of a false reactive response in VAST analysis, when the fetus is affected by a CNS disorder. Increased numbers of FM after VAS suggest that the vibratory pathway is more likely to elicit fetal response than the auditory pathway in this setting, and that the vibratory stimulation travels by subcortical rather than by cortical pathways.

Serum selenium level in healthy Koreans.

Of trace elements in the serum of living organisms, selenium (Se) is an essential mineral and plays the role of an antioxidant as selenoproteins protecting the organism against oxidative damage induced by hydrogen peroxide, other lipid hydroperoxides, and their derivatives. The aim of this study was to determine the mean serum Se levels in healthy Korean volunteers (50 males and 50 females) by using an inductively coupled plasma-mass spectrometry method. The samples were collected at the Health Promotion Centre of Kangnam St. Mary's Hospital, College of Medicine, the Catholic University of Korea, Kangnam District, Seoul in accordance with procedures approved by the Institutional Review Board of the Catholic University of Korea. The mean serum Se level in healthy subjects was 112.05 +/- 30.42 microg/l. For gender, it was 120.81 +/- 27.37 microg/l for females and 103.29 +/- 31.05 microg/l for males. From the study result, there was a significant difference between the mean Se concentrations of gender groups (p = 0.0035). Also, the study indicated no effect of age on Se levels (p > 0.05) in the healthy individuals.