Unusual transport characteristics of nitrogen-doped single-walled carbon nanotubes

Electrical transport characteristics of nitrogen-doped single-walled carbon nanotubes (N-SWCNTs), in which the nitrogen dopant is believed to form a pyridinelike bonding configuration, are studied with the field effect transistor operations. Contrary to the expectation that the nitrogen atoms may induce a n -type doping, the electrical transports through our N-SWCNTs are either ambipolar in vacuum or p -type in air. Through the first-principles electronic structure calculations, we show that the nitrogen dopant indeed favors the pyridinelike configuration and the Fermi level of the pyridinelike N-SWCNT is almost at the intrinsic level.open01

Fulminant myocarditis managed with pulsatile extracorporeal life support; use of Twin Pulse Life support (T-PLS®)

Fulminant myocarditis frequently results in severe hemodynamic deterioration. High-dose vasopressors or sometimes mechanical circulatory support are required. We report on two cases of fulminant myocarditis successfully treated with pulsatile extracorporeal life support (T-PLS®, Twin Pulse Life support, New heart bio.BHK, Seoul, Korea). With T-PLS, we were able to provide mechanical support to patients until they recovered completely

catena-Poly[[bis­(N,N-dimethyl­formamide-κO)zinc]-μ2-oxalato-κ4 O 1,O 2:O 1′,O 2′]

In the crystal structure of the title compound, [Zn(C2O4)(C3H7NO)2]n, the ZnII ion is situated on a twofold rotation axis and has a distorted octa­hedral coordination geometry defined by the O atoms of two dimethyl­formamide mol­ecules and four O atoms of two bidentate oxalate ligands. The oxalate anion is located on an inversion centre and bridges two metal ions, resulting in a polymeric structure with infinite zigzag chains extending parallel to [010]

Tumor hypoxia and reoxygenation: the yin and yang for radiotherapy.

Tumor hypoxia, a common feature occurring in nearly all human solid tumors is a major contributing factor for failures of anticancer therapies. Because ionizing radiation depends heavily on the presence of molecular oxygen to produce cytotoxic effect, the negative impact of tumor hypoxia had long been recognized. In this review, we will highlight some of the past attempts to overcome tumor hypoxia including hypoxic radiosensitizers and hypoxia-selective cytotoxin. Although they were (still are) a very clever idea, they lacked clinical efficacy largely because of ‘reoxygenation’ phenomenon occurring in the conventional low dose hyperfractionation radiotherapy prevented proper activation of these compounds. Recent meta-analysis and imaging studies do however indicate that there may be a significant clinical benefit in lowering the locoregional failures by using these compounds. Latest technological advancement in radiotherapy has allowed to deliver high doses of radiation conformally to the tumor volume. Although this technology has brought superb clinical responses for many types of cancer, recent modeling studies have predicted that tumor hypoxia is even more serious because ‘reoxygenation’ is low thereby leaving a large portion of hypoxic tumor cells behind. Wouldn’t it be then reasonable to combine hypoxic radiosensitizers and/or hypoxia-selective cytotoxin with the latest radiotherapy? We will provide some preclinical and clinical evidence to support this idea hoping to revamp an enthusiasm for hypoxic radiosensitizers or hypoxia-selective cytotoxins as an adjunct therapy for radiotherapy. © 2016. The Korean Society for Radiation Oncology.11Yscopu

Menthol Enhances an Antiproliferative Activity of 1α,25-Dihydroxyvitamin D3 in LNCaP Cells

1α,25-dihydroxyvitamin D3 [1α,25(OH)2D3], the most active form of vitamin D3, and its analogues have therapeutic benefits for prostate cancer treatment. However, the development of hypercalcemia is an obstacle to clinical applications of 1α,25(OH)2D3 for cancer therapy. In this study, we provide evidence that menthol, a key component of peppermint oil, increases an anti-proliferation activity of 1α,25(OH)2D3 in LNCaP prostate cancer cells. We found that menthol per se does not exhibit antiproliferative activity, but it is able to enhance 1α,25(OH)2D3-mediated growth inhibition in LNCaP cells. Fluorometric assays using Fura-2 showed that 1α,25(OH)2D3 does not induce acute Ca2+ response, whereas menthol evokes an increase in [Ca2+]i, which suggests that cross-talks of menthol-induced Ca2+ signaling with 1α,25(OH)2D3-mediated growth inhibition pathways. In addition, Western blot analysis revealed that 1α,25(OH)2D3 and menthol cooperatively modulate the expression of bcl-2 and p21 which provides the insight into the molecular mechanisms underlying the enhanced 1α,25(OH)2D3-mediated growth inhibition by menthol. Thus, our findings suggest that menthol may be a useful natural compound to enhance therapeutic effects of 1α,25(OH)2D3

Results of Air Caloric and Other Vestibular Tests in Patients with Chronic Otitis Media

ObjectivesAir caloric results are supposed to be influenced by anatomic changes of the middle ear. The aims of our study were to evaluate the incidence and characteristics of abnormal air caloric results in patients with unilateral chronic otitis media and without any history of vertigo, and to compare caloric results with there of other vestibular function tests (VFTs).MethodsTwenty five patients with unilateral chronic otitis media (COM) who were scheduled for surgery underwent VFTs preoperatively. Hearing was assessed using pure-tone audiometry and vestibular function was assessed using a set of VFTs: air caloric, head-shaking nystagmus (HSN), vibration-induced nystagmus (VIN), and subjective visual vertical (SVV) tests.ResultsSix patients (24%) showed pathologic canal paresis (CP) on COM-sided ears. Two patients showed pathologic CP on the contralateral side. However, both of the two showed inverted nystagmus to warm air stimulation on the COM-side and hyperactive nystagmus to cold air stimulation on the COM-side, which means that the COM-sided ear was stimulated too much. There was pathologic HSN in 12 patients (48%), pathologic VIN in 7 (28%), and pathologic SVV in 5 (20%). Overall, 20 (80%) patients showed abnormal findings through a set of VFTs. Patients with an interaural difference of bone-conduction hearing thresholds ≥10 dB tended to show more abnormal VFT results than those for whom the interaural difference of bone-conduction hearing thresholds was <10 dB.ConclusionOur data show that one-fourth of patients with unilateral COM show abnormal caloric results on the COM side. However, subclinical latent vestibular imbalances were found to be common, which might be related to the gradual vestibular involvement in inflammatory processes, regardless of the caloric results. Results of a set of VFTs should be referred to when determining vestibular imbalance in patients with COM

Decision tree-based approach for online management of PEM fuel cells for residential application

This thesis demonstrates a new intelligent technique for the online optimal management of PEM fuel cells units for onsite energy production to supply residential utilizations. Classical optimization techniques are based on offline calculations and cannot provide the necessary computational speed for online performance. In this research, a Decision Tree (DT) algorithm is employed to obtain the optimal, or quasioptimal, settings of the fuel cell online and in a general framework. The main idea is to employ a classification technique, trained on a sufficient subset of data, to produce an estimate of the optimal setting without repeating the optimization process. A database is extracted from a previously-performed Genetic Algorithm (GA)-based optimization has been used to create a suitable decision tree, which was intended for generalizing the optimization results. The approach provides the flexibility of adjusting the settings of the fuel cell online according to the observed variations in the tariffs and load demands. Results at different operating conditions are presented to confirm the high accuracy of the proposed generalization technique. The accuracy of the decision tree has been tested by evaluating the relative error with respect to the optimized values. Then, the possibility of pruning the tree has been investigated in order to simplify its structure without affecting the accuracy of the results. In addition, the accuracy of the DTs to approximate the optimal performance of the fuel cell is compared to that of the Artificial Neural Networks (ANNs) used for the same purpose. The results show that the DTs can somewhat outperform the ANNs with certain pruning levels

Identification of restoration species for early roadcut slope regeneration using functional group approach

Current restoration protocols for roadside cut slopes in South Korea involve hydroseeding with exotic species to achieve early greening and soil stabilization. However, exotic species can negatively affect adjacent native ecosystems. This study investigated the functional traits of early colonizers in slope restoration and surrounding environments to inform restoration methods that generate similar communities as those of native ecosystems. Slope vegetation (species density, species cover, upperstory species, canopy cover) and environment (aspect, angle, soil properties) were surveyed from the road edge to the forest boundary, and were classified as three distinct zones: a hydroseeded slope, a transition zone, and the forest edge. Naturally occurring species were classified into functional groups to examine dominant traits during early colonization. Hemicryptophyte or geophyte forest species and forest interior woody species were well established and dominant in transition zones and cut slopes. Potential native species for slope restoration can be identified by examining functional group species in the adjacent forest. These native species can achieve restoration goals and block invasive species in the same functional group. Festuca arundinacea (tall fescue), which is reported as an invasive alien species, rapidly spread after introduction for restoration. Thus, continuous monitoring for impact on native communities is required after sowing invasive alien species. Future slope restoration should consider native woody species and perennial forest sedge species that develop rhizomes, and reconsider the use of tall fescue. This study indicates that cut slopes can be appropriately managed to enhance the quality of habitats for native species.N