Surface Passivation of Layered MoSe2 via van der Waals Stacking of Amorphous Hydrocarbon

Development of efficient surface passivation methods for semiconductor devices is crucial to counter the degradation in their electrical performance owing to scattering or trapping of carriers in the channels induced by molecular adsorption from the ambient environment. However, conventional dielectric deposition involves the formation of additional interfacial defects associated with broken covalent bonds, resulting in accidental electrostatic doping or enhanced hysteretic behavior. In this study, centimeter-scaled van der Waals passivation of transition metal dichalcogenides (TMDCs) is demonstrated by stacking hydrocarbon (HC) dielectrics onto MoSe₂ field-effect transistors (FETs), thereby enhancing the electric performance and stability of the device, accompanied with the suppression of chemical disorder at the HC/TMDCs interface. The stacking of HC onto MoSe₂ FETs enhances the carrier mobility of MoSe₂ FET by over 50% at the n-branch, and a significant decrease in hysteresis, owing to the screening of molecular adsorption. The electron mobility and hysteresis of the HC/MoSe₂ FETs are verified to be nearly intact compared to those of the fabricated HC/MoSe₂ FETs after exposure to ambient environment for 3 months. Consequently, the proposed design can act as a model for developing advanced nanoelectronics applications based on layered materials for mass production.

Quantitation of propionic acid in emmental cheese products by direct solvent extraction

Propionic acid (PA) is commonly present in Emmental cheese (EM) with relatively high concentration. Even though PA is allowed as GRAS in the USA, it may cause neurological disorders if it is consumed excessively. The maximum level of the preservative PA in cheese is set at 3.0 g/kg by the Korean Food Code. Also, the minimum level of PA in EM (150 mg / 100 g) was set by Codex in 1967. Therefore, PA monitoring in EM, with relatively high level of intrinsic PA, is necessary to recommend the sound use of the PA in the EM ripened. The current official PA analysis method consisting of steam distillation and solvent extraction / evaporation, is too cumbersome to be handled in sample preparation process. In this study, acidic acetone-based direct extraction method was successfully applied to 12 EM samples for the determination of PA level.

Purification Method for Multi-residual Pesticides in Green Tea

Dried green tea leaves, fortified with more than 190 multi-class pesticides, were analyzed by the newly modified Luke multiresidue method. This consists of acetone-acetonitrile extraction, dichloromethane partition and florisil cartridge purification, eluting with n-hexane-dichloromethane-acetonitrile (50:45:5), which was optimized in this study. The final sample, in n-hexane, was analyzed by GC-ECD and/or NPD. Of the 194 pesticides tested, 147 pesticides were recovered with more than 70% from dried green tea leaves. Eighteen pesticides were not recovered at all with this method.

Interregional correlations of glucose metabolism between the basal ganglia and different cortical areas: an ultra-high resolution PET/MRI fusion study using 18F-FDG

Basal ganglia have complex functional connections with the cerebral cortex and are involved in motor control, executive functions of the forebrain, such as the planning of movement, and cognitive behaviors based on their connections. The aim of this study was to provide detailed functional correlation patterns between the basal ganglia and cerebral cortex by conducting an interregional correlation analysis of the ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography (PET) data based on precise structural information. Fifteen participants were scanned with 7-Tesla magnetic resonance imaging (MRI) and high resolution research tomography (HRRT)-PET fusion system using ¹⁸F-FDG. For detailed interregional correlation analysis, 24 subregions of the basal ganglia including pre-commissural dorsal caudate, post-commissural caudate, pre-commissural dorsal putamen, post-commissural putamen, internal globus pallidus, and external globus pallidus and 80 cerebral regions were selected as regions of interest on the MRI image and their glucose metabolism were calculated from the PET images. Pearson's product-moment correlation analysis was conducted for the interregional correlation analysis of the basal ganglia. Functional correlation patterns between the basal ganglia and cerebral cortex were not only consistent with the findings of previous studies, but also showed new functional correlation between the dorsal striatum (i.e., caudate nucleus and putamen) and insula. In this study, we established the detailed basal ganglia subregional functional correlation patterns using ¹⁸F-FDG PET/MRI fusion imaging. Our methods and results could potentially be an important resource for investigating basal ganglia dysfunction as well as for conducting functional studies in the context of movement and psychiatric disorders.

Production of a fermented organic rice syrup with higher isomalto-oligosaccharide using Lactobacillus plantarum

Isomalto-oligosaccharide (IMO) syrup was prepared from organic rice, in which Lactobacillus plantarum as a starter was inoculated to raise its purity and also produce a fermented rice beverage. Of the five strains of lactic acid bacteria tested, L. plantarum was preferentially selected in terms of a viable cells (7.3 × 10⁸ colony forming unit (CFU/mL) and higher dry cell weight (13 mg/mL). The fermented syrup-based medium did not affect the growth of L. plantarum. As expected, the residual sugar content gradually decreased by 1.34% compared with the initial concentration. It was apparent that the residual sugars but not oligosaccharides were removed during the L. plantarum fermentation period. The production of lactic acid was the highest (8125.78 mg/kg) among the organic acids produced in the fermented IMO syrup.

Optical bistability and multistability via quantum coherence in chiral molecules

The optical bistability (OB) and multistability (OM) in chiral molecules are investigated by placing the sample into a unidirectional ring cavity. Because of broken mirror symmetry of the effective potential, the chiral molecules have a cyclic three-level Δ-configuration structure, in which one- and two-photon transitions can coexist. We find that the OB is achievable in this system on exact one-, two- and three-photon resonance conditions but absent in the three-level Λ-type system under the two-photon resonance. Moreover, the OM and the switching between OB and OM are also realized by choosing parameters properly. Interestingly, the left- and right-handed chiral molecules exhibit different bistable and multistable behaviors. It is shown that the threshold intensity of OB is strongly dependent on the percentage of the two enantiomers in the mixture. This provides an effective approach to probe molecular chirality and to determine enantiomer excess, which may find potential application in organic chemistry, pharmacology, biochemistry, etc..

Dynamics of quantum correlation between separated nitrogen-vacancy centers embedded in plasmonic waveguide

We investigate the dynamics of quantum correlation between two separated nitrogen vacancy centers (NVCs) placed near a one-dimensional plasmonic waveguide. As a common medium of the radiation field of NVCs propagating, the plasmonic waveguide can dynamically induce quantum correlation between the two NVCs. It is interesting to find that such dynamically induced quantum correlation can be preserved in the long-time steady state by locally applying individual driving on the two NVCs. In particular, we also show that a large degree of quantum correlation can be established by this scheme even when the distance between the NVCs is much larger than their operating wavelength. This feature may open new perspectives for devising active decoherence-immune solid-state optical devices and long-distance NVC-based quantum networks in the context of plasmonic quantum electrodynamics.

Galactooligosaccharide and Sialyllactose Content in Commercial Lactose Powders from Goat and Cow Milk

The most commonly used infant formulas contain lactose originating from cow milk. Goat milk has recently been claimed to be nutritionally more effective for infants than other milks. In baby foods, much emphasis is placed on the concentrations of intestinal microflora-promoting oligosaccharides, which are generally transferred into lactose from milk during crystallization process. Here we show that higher level of free sialic acid is present in goat lactose powder compared to cow lactose powder. Without proteinase K treatment, the amount of 3-sialyllactose and 6-sialyllactose were similar in goat and cow lactose powders. However, after proteolysis, 6-sialyllactose was present at higher levels in goat than in cow lactose powder. Galactooligosaccharides, a group of prebiotics, are present in milk in the form of glycoproteins. Galactooligosaccharide content was also higher in goat lactose powder than in cow lactose powder.

Majorana transport in superconducting nanowire with Rashba and Dresselhaus spin-orbit couplings

The tunneling experiment is a key technique for detecting Majorana fermion (MF) in solid state systems. We use Keldysh non-equilibrium Green function method to study two-lead tunneling in superconducting nanowire with Rashba and Dresselhaus spin-orbit couplings. A zero-bias dc conductance peak appears in our setup which signifies the existence of MF and is in accordance with previous experimental results on InSb nanowire. Interestingly, due to the exotic property of MF, there exists a hole transmission channel which makes the currents asymmetric at the left and right leads. The ac current response mediated by MF is also studied here. To discuss the impacts of Coulomb interaction and disorder on the transport property of Majorana nanowire, we use the renormalization group method to study the phase diagram of the wire. It is found that there is a topological phase transition under the interplay of superconductivity and disorder. We find that the Majorana transport is preserved in the superconducting-dominated topological phase and destroyed in the disorder-dominated non-topological insulator phase.

Severity of acute and chronic urticaria correlates with D-dimer level, but not C-reactive protein or total IgE

BACKGROUND

Although various scoring systems for measuring urticaria severity have been introduced, most rely on subjective criteria. Therefore, additional objective criteria such as laboratory markers would be helpful adjuncts in making this assessment.

AIM

To evaluate the usefulness of three laboratory markers [D-dimer, C-reactive protein (CRP), and total IgE] in assessing disease severity of both acute urticaria (AU) and chronic urticaria (CU).

METHODS

We conducted a retrospective analysis of 94 patients with urticaria. Correlations between the aforementioned laboratory markers and the Urticaria Activity Score (UAS) were calculated.

RESULTS

A substantial proportion of patients with urticaria (acute 43.5%; chronic 39.6%) had an increased D-dimer level. Additionally, there was a significant correlation between D-dimer level and UAS (AU r = 0.60, P < 0.001; CU r = 0.37, P < 0.05). However, there was no significant correlation between UAS and either CRP or total IgE.

CONCLUSIONS

D-dimer level could be used as a marker of disease severity for both AU and CU. However, CRP and total IgE are not as reliable in predicting disease severity.

Canonical versus noncanonical equilibration dynamics of open quantum systems

In statistical mechanics, any quantum system in equilibrium with its weakly coupled reservoir is described by a canonical state at the same temperature as the reservoir. Here, by studying the equilibration dynamics of a harmonic oscillator interacting with a reservoir, we evaluate microscopically the condition under which the equilibration to a canonical state is valid. It is revealed that the non-Markovian effect and the availability of a stationary state of the total system play a profound role in the equilibration. In the Markovian limit, the conventional canonical state can be recovered. In the non-Markovian regime, when the stationary state is absent, the system equilibrates to a generalized canonical state at an effective temperature; whenever the stationary state is present, the equilibrium state of the system cannot be described by any canonical state anymore. Our finding of the physical condition on such noncanonical equilibration might have significant impact on statistical physics. A physical scheme based on circuit QED is proposed to test our results.

Test of genuine multipartite nonlocality without inequalities

In this Letter we propose a set of conditions on the joint probabilities as a test of genuine multipartite nonlocality without inequality. Our test is failed by all nonsignaling local models in which even nonlocal correlations among some observables (not all) are allowed as long as these correlations respect the nonsignaling principle. A pass of our test by a state therefore indicates that this state cannot be simulated by any nonsignaling local models; i.e., the state exhibits genuine multipartite nonlocality. It turns out that all entangled symmetric n-qubit (n≥3) states pass our test and therefore are n-way nonlocal. Also we construct two Bell-type inequalities from our proposed test whose violations indicate genuine multipartite nonlocal correlations.

Test of Einstein-Podolsky-Rosen steering based on the all-versus-nothing proof

In comparison with entanglement and Bell nonlocality, Einstein-Podolsky-Rosen steering is a newly emerged research topic and in its incipient stage. Although Einstein-Podolsky-Rosen steering has been explored via violations of steering inequalities both theoretically and experimentally, the known inequalities in the literatures are far from well-developed. As a result, it is not yet possible to observe Einstein-Podolsky-Rosen steering for some steerable mixed states. Recently, a simple approach was presented to identify Einstein-Podolsky-Rosen steering based on all-versus-nothing argument, offering a strong condition to witness the steerability of a family of two-qubit (pure or mixed) entangled states. In this work, we show that the all-versus-nothing proof of Einstein-Podolsky-Rosen steering can be tested by measuring the projective probabilities. Through the bound of probabilities imposed by local-hidden-state model, the proposed test shows that steering can be detected by the all-versus-nothing argument experimentally even in the presence of imprecision and errors. Our test can be implemented in many physical systems and we discuss the possible realizations of our scheme with non-Abelian anyons and trapped ions.

Detecting and estimating continuous-variable entanglement by local orthogonal observables

Entanglement detection and estimation are fundamental problems in quantum information science. Compared with discrete-variable states, for which lots of efficient entanglement detection criteria and lower bounds of entanglement measures have been proposed, the continuous-variable entanglement is much less understood. Here we shall present a family of entanglement witnesses based on continuous-variable local orthogonal observables (CVLOOs) to detect and estimate entanglement of Gaussian and non-Gaussian states, especially for bound entangled states. By choosing an optimal set of CVLOOs, our entanglement witness is equivalent to the realignment criterion and can be used to detect bound entanglement of a class of 2+2 mode Gaussian states. Via our entanglement witness, lower bounds of two typical entanglement measures for arbitrary two-mode continuous-variable states are provided.

Intrinsic dynamical fluctuation assisted symmetry breaking in adiabatic following

Classical adiabatic invariants in actual adiabatic processes possess intrinsic dynamical fluctuations. The magnitude of such intrinsic fluctuations is often thought to be negligible. This widely believed physical picture is contested here. For adiabatic following of a moving stable fixed-point solution facing a pitchfork bifurcation, we show that intrinsic dynamical fluctuations in an adiabatic process can assist in a deterministic selection between two symmetry-connected fixed-point solutions, with the outcome independent of the duration of the adiabatic process. Using a classical model Hamiltonian also relevant to a two-mode quantum system, we further demonstrate the formation of an adiabatic hysteresis loop in purely Hamiltonian mechanics and the generation of a Berry phase via changing one single-valued parameter only.

Greenberger-Horne-Zeilinger paradoxes from qudit graph states

One fascinating way of revealing quantum nonlocality is the all-versus-nothing test due to Greenberger, Horne, and Zeilinger (GHZ) known as the GHZ paradox. So far genuine multipartite and multilevel GHZ paradoxes are known to exist only in systems containing an odd number of particles. Here we shall construct GHZ paradoxes for an arbitrary number (greater than 3) of particles with the help of qudit graph states on a special kind of graphs, called GHZ graphs. Furthermore, based on the GHZ paradox arising from a GHZ graph, we derive a Bell inequality with two d-outcome observables for each observer, whose maximal violation attained by the corresponding graph state, and a Kochen-Specker inequality testing the quantum contextuality in a state-independent fashion.

All entangled pure states violate a single Bell's inequality

We show that a single Bell's inequality with two dichotomic observables for each observer, which originates from Hardy's nonlocality proof without inequalities, is violated by all entangled pure states of a given number of particles, each of which may have a different number of energy levels. Thus Gisin's theorem is proved in its most general form from which it follows that for pure states Bell's nonlocality and quantum entanglement are equivalent.

Strongly interacting photons in asymmetric quantum well via resonant tunneling

We propose an asymmetric quantum well structure to realize strong interaction between two slow optical pulses. The essential idea is the combination of the advantages of inverted-Y type scheme and resonant tunneling. We analytically demonstrate that giant cross-Kerr nonlinearity can be achieved with vanishing absorptions. Owing to resonant tunneling, the contributions of the probe and signal cross-Kerr nonlinearities to total nonlinear phase shift vary from destructive to constrictive, leading to nonlinear phase shift on order of π at low light level. In this structure, the scheme is inherent symmetric for the probe and signal pulses. Consequently, the condition of group velocity matching can be fulfilled with appropriate initial electron distribution.

State-independent proof of Kochen-Specker theorem with 13 rays

Quantum contextuality, as proved by Kochen and Specker, and also by Bell, should manifest itself in any state in any system with more than two distinguishable states and recently has been experimentally verified. However, for the simplest system capable of exhibiting contextuality, a qutrit, the quantum contextuality is verified only state dependently in experiment because too many (at least 31) observables are involved in all the known state-independent tests. Here we report an experimentally testable inequality involving only 13 observables that is satisfied by all noncontextual realistic models while being violated by all qutrit states. Thus our inequality facilitates a state-independent test of the quantum contextuality for an indivisible quantum system. We also provide a record-breaking state-independent proof of the Kochen-Specker theorem with 13 directions determined by 26 points on the surface of a magic cube.

Fault-tolerant Greenberger-Horne-Zeilinger paradox based on non-Abelian anyons

We propose a scheme to test the Greenberger-Horne-Zeilinger paradox based on braidings of non-Abelian anyons, which are exotic quasiparticle excitations of topological states of matter. Because topological ordered states are robust against local perturbations, this scheme is in some sense "fault-tolerant" and might close the detection inefficiency loophole problem in previous experimental tests of the Greenberger-Horne-Zeilinger paradox. In turn, the construction of the Greenberger-Horne-Zeilinger paradox reveals the nonlocal property of non-Abelian anyons. Our results indicate that the non-Abelian fractional statistics is a pure quantum effect and cannot be described by local realistic theories. Finally, we present a possible experimental implementation of the scheme based on the anyonic interferometry technologies.

Investigation of the cyanuric acid contamination caused by acetonitrile and alkali detergent for the LC-ESI MS/MS analysis

During the replicate analysis of melamine and cyanuric acid by LC-ESI MS/MS for the method development, recurring cyanuric acid contamination was observed. The high concentration (6,950 mg/kg) of cyanuric acid was found in the strong alkali detergent used in a glassware washing machine. However, only small concentration of cyanuric acid (0.002-0.004 mg/kg) was detected in the glassware washed with the above alkali detergent. The major contamination source of cyanuric acid was some specific lot of acetonitrile (0.093 mg/kg) that increased the background level of the ion chromatogram.

The level of vitamin D in the serum correlates with fatty degeneration of the muscles of the rotator cuff

This study examined the role of vitamin D as a factor accounting for fatty degeneration and muscle function in the rotator cuff. There were 366 patients with disorders of the shoulder. A total of 228 patients had a full-thickness tear (group 1) and 138 patients had no tear (group 2). All underwent magnetic resonance arthrography and an isokinetic muscle performance test. The serum concentrations of vitamin D (25(OH)D(3)) were measured. In general, a lower serum level of vitamin D was related to higher fatty degeneration in the muscles of the cuff. Spearman's correlation coefficients were 0.173 (p = 0.001), -0.181 (p = 0.001), and -0.117 (p = 0.026) for supraspinatus, infraspinatus and subscapularis, respectively. In group 1, multivariate linear regression analysis revealed that the serum level of vitamin D was an independent variable for fatty degeneration of the supraspinatus and infraspinatus. The serum vitamin D level has a significant negative correlation with the fatty degeneration of the cuff muscle and a positive correlation with isokinetic muscle torque.

Geometric entangling gates in decoherence-free subspaces with minimal requirements

We introduce a new strongly driven dispersive atom-cavity interaction and develop a new scheme for implementing the nontrivial entangling gates for two logical qubits in decoherence-free subspaces (DFSs). Our scheme combines the robust advantages of DFS and the geometric phase. Moreover, only two neighboring physical qubits, which encode a logical qubit, are required to undergo the collective dephasing in our scheme.

Butyl and phenyl tin compounds in fish and shellfish on the Korean market

The degree of organotin contamination was determined in samples of ten species of fish and shellfish that were representative of the Korean fish market. Shellfish and fish samples were collected in the fish markets of eight big cities in Korea (Gangneung, Ulsan, Pusan, Daegu, Guangju, Daejun, Incheon and Seoul). The edible portion of total 160 samples were analyzed for organotin compounds such as monobutltin (MBT), dibutyltin (DBT), tributyltin (TBT), monophenyltin (MPT), diphenyltin (DPT) and TPT (triphenyltin) by GC-MSD SIM mode after propylation and Florisil clean-up. Generally organotin levels of fish were higher than shellfish. The highest concentration of TBT was found in mackerel (average 67.02 ng/g-wet wt.) among fish and shellfish. TBT usually accounted higher percentage than that of MBT and DBT in most samples. However, the average concentration order of PTs in the tested samples was MPT > TPT > DPT except saury.

Monitoring of residual pesticides in herbal drug materials of Korea and China

The information of the pesticide residues in herbal drug materials (HDMs) is not sufficient to support the scientific risk management so far. Therefore, 30 types of HDMs such as the herba of Artemisia montana were analyzed for 47 different pesticides. Among 292 samples, eight Chinese and one Korean HDMs were contaminated with five pesticides such as methoxychlor, DDT, gamma-BHC, endosulfan, and procymidone (0.044-0.501 mg/kg). The detection rate of pesticides in the tested HDMs was determined as 3.1%. On critical observation of the detected amount of procymidone (0.501 mg/kg) and methoxychlor (0.382 and 0.312 mg/kg), further intensive monitoring of the pesticides might be necessary for HDMs.

Characterization and quantification of anthocyanins in grape juices obtained from the grapes cultivated in Korea by HPLC/DAD, HPLC/MS, and HPLC/MS/MS

The characterization and quantification of anthocyanins in grape cultivars of Oll-Meoru (Vitis coignetiaexVitis labrusca), Neut-Meoru (Vitis coignetiaexVitis labrusca), Muscal Bailey A. (Vitis labruscana), and Campbell Early (Vitis labruscaxV. vinifera) cultivated in Korea were carried out by partial purification through XAD-7 column chromatography followed by C-18 HPLC/diode array detector (DAD), HPLC/MS, and HPLC/MS/MS analyses. The column oven temperature during the reverse phase C-18 HPLC greatly affected the separation of individual anthocyanins. The result showed that the optimum column oven temperature was 35 degrees C. Sixteen different anthocyanins (11 nonacylated and 5 acylated anthocyanins) were identified in the grape juices. Oll-Meoru, Neut-Meoru, and Muscat Bailey A (MBA) grape juices contained only nonacylated anthocyanins. Oll-Meoru and Neut-Meoru grape juices had same anthocyanins, but their proportions were considerably different. Peonidin 3,5-diglucoside and malvidin 3,5-diglucoside were the major anthocyanins in Oll-Meoru grape juice. Delphinidin 3-glucoside was, however, the major anthocyanin in Neut-Meoru grape juice. Peonidin 3-glucoside and malvidin 3-glucoside were the most abundant anthocyanins in Muscal Bailey A grape juice. Campbell Early grape juice contained both nonacylated and acylated anthocyanins. Cyanidin 3-(p-coumaroyl)glucoside-5-glucoside and peonidin 3-(p-coumaroyl)glucoside-5-glucoside were the most abundant anthocyanins in Campbell Early grape juice. Total anthocyanin contents were greatly different in different grape jucies, with the highest in Neut-Meoru juice (1043.5 microg/mL), followed by Oll-Meoru (997.7 microg/mL), MBA (390.2 microg/mL), and Campbell Early (183.9 microg/mL) juices. The total anthocyanin content in Neut-Meoru grape juice was 5.67 times higher than that in Campbell Early grape juice. This represents the 1st report on the systematic characterization and quantification of anthocyanins in the juices of these grapes cultivated in Korea.

Nonadditive quantum error-correcting code

We report the first nonadditive quantum error-correcting code, namely, a ((9, 12, 3)) code which is a 12-dimensional subspace within a 9-qubit Hilbert space, that outperforms the optimal stabilizer code of the same length by encoding more levels while correcting arbitrary single-qubit errors. Taking advantage of the graph states, we construct explicitly a complete encoding-decoding circuit for the proposed nonadditive error-correcting code.

Directed differentiation of human embryonic stem cells towards a pancreatic cell fate

AIMS/HYPOTHESIS

The relative lack of successful pancreatic differentiation of human embryonic stem cells (hESCs) may suggest that directed differentiation of hESCs into definitive endoderm and subsequent commitment towards a pancreatic fate are not readily achieved. The aim of this study was to investigate whether sequential exposure of hESCs to epigenetic signals that mimic in vivo pancreatic development can efficiently generate pancreatic endodermal cells, and whether these cells can be further matured and reverse hyperglycaemia upon transplantation.

MATERIALS AND METHODS

The hESCs were sequentially treated with serum, activin and retinoic acid (RA) during embryoid body formation. The patterns of gene expression and protein production associated with embryonic germ layers and pancreatic endoderm were analysed by RT-PCR and immunostaining. The developmental competence and function of hESC-derived PDX1-positive cells were evaluated after in vivo transplantation.

RESULTS

Sequential treatment with serum, activin and RA highly upregulated the expression of the genes encoding forkhead box protein A2 (FOXA2), SRY-box containing gene 17 (SOX17), pancreatic and duodenal homeobox 1 (PDX1) and homeobox HB9 (HLXB9). The population of pancreatic endodermal cells that produced PDX1 was significantly increased at the expense of ectodermal differentiation, and a subset of the PDX1-positive cells also produced FOXA2, caudal-type homeobox transcription factor 2 (CDX2), and nestin (NES). After transplantation, the PDX1-positive cells further differentiated into mature cell types producing insulin and glucagon, resulting in amelioration of hyperglycaemia and weight loss in streptozotocin-treated diabetic mice.

CONCLUSIONS/INTERPRETATION

Our strategy allows the progressive differentiation of hESCs into pancreatic endoderm capable of generating mature pancreatic cell types that function in vivo. These findings may establish the basis of further investigations for the purification of transplantable islet progenitors derived from hESCs.

Multi residual pesticide monitoring in commercial herbal crude drug materials in South Korea

In order to reduce health risks from residual pesticides in herbal drug products, the residue information of pesticides should be acquired. Therefore, 38 commodities (229 herbal crude drug materials) were analyzed for 44 different pesticides. Among the 229 samples (36 types of herbal crude drugs), seven imported and two domestic drug materials were contaminated with eight pesticides (0.034-0.579 mg/kg) such as BHC, procymidone, endosulfan, etc. Among the eight detected pesticides, four were fungicides, which were found in underground crude drug materials such as rhizoma or radix.

Sufficiency criterion for the validity of the adiabatic approximation

We examine the quantitative condition which has been widely used as a criterion for the adiabatic approximation but was recently found insufficient. Our results indicate that the usual quantitative condition is sufficient for a special class of quantum mechanical systems. For general systems, it may not be sufficient, but it, along with additional conditions, is sufficient. The usual quantitative condition and the additional conditions constitute a general criterion for the validity of the adiabatic approximation, which is applicable to all N-dimensional quantum systems. Moreover, we illustrate the use of the general quantitative criterion in some physical models.

Optically induced spin-Hall effect in atoms

We propose an optical means to realize the spin-Hall effect (SHE) in a neutral atomic system by coupling the internal spin states of atoms to radiation. The interaction between the external optical fields and the atoms creates effective magnetic fields that act in opposite directions on "electrically" neutral atoms with opposite spin polarizations. This effect leads to a Landau level structure for each spin orientation in direct analogy with the familiar SHE in semiconductors. The conservation and topological properties of the spin current, and the creation of a pure spin current are discussed.

Phase contrast radiography of Lewy bodies in Parkinson disease

Parkinson's disease (PD), defined as a neurodegenerative disorder, is characterized by the loss of dopaminergic neurons and the presence of Lewy bodies in neurons. Morphological study of Lewy bodies is important to identify the causes and the processes of PD. Here, we investigate a possibility of phase contrast radiography using coherent synchrotron X-rays to explore the microscopic details of Lewy bodies in thick (approximately 3 mm) midbrain tissues. Autopsied midbrain tissues of a PD patient were sliced in 3 mm thickness and then examined using synchrotron X-rays from the 7B2 beamline of the Pohang Light Source. Refraction-enhanced phase contrast radiography and microtomography were adopted to identify dark core and dim edge of Lewy bodies in neurons. The morphology of Lewy bodies was clearly revealed by the phase contrast radiography in very thick (3 mm) midbrain tissues without any staining treatment. Three-dimensional volume rendered microtomography of the autopsied midbrain tissues demonstrates striking evidence that several Lewy bodies are agglomerated by dim edges in a neuron. We suggest that the phase contrast radiography could be a useful tool to morphologically investigate the causes or the processes in PD.

Quantitative conditions do not guarantee the validity of the adiabatic approximation

In this Letter, we point out that the widely used quantitative conditions in the adiabatic theorem are insufficient in that they do not guarantee the validity of the adiabatic approximation. We also reexamine the inconsistency issue raised by Marzlin and Sanders [Phys. Rev. Lett. 93, 160408 (2004)] and elucidate the underlying cause.

Experimental quantum cloning with prior partial information

When prior partial information about a state to be cloned is available, it can be cloned with a fidelity higher than that of universal quantum cloning. We experimentally verify this intriguing relationship between the cloning fidelity and the prior information by reporting the first experimental optimal quantum state-dependent cloner, using nuclear magnetic resonance techniques. Our experiments may further cast important implications into many quantum information processing protocols.

Qutrit state engineering with biphotons

The novel experimental realization of three-level optical quantum systems is presented. We use the polarization state of biphotons to generate a specific sequence of states that are used in the extended version of four-state QKD protocol quantum key distribution protocol. We experimentally verify the orthogonality of the basic states and demonstrate the ability to easily switch between them. The tomography procedure is employed to reconstruct the density matrices of generated states.

Gisin's theorem for three qubits

We present a theorem that all generalized Greenberger-Horne-Zeilinger states of a three-qubit system violate a Bell inequality in terms of probabilities. All pure entangled states of a three-qubit system are shown to violate a Bell inequality for probabilities; thus, one has Gisin's theorem for three qubits.

Kinematic approach to the mixed state geometric phase in nonunitary evolution

A kinematic approach to the geometric phase for mixed quantal states in nonunitary evolution is proposed. This phase is manifestly gauge invariant and can be experimentally tested in interferometry. It leads to well-known results when the evolution is unitary.

Coincidence bell inequality for three three-dimensional systems

We construct a Bell inequality for coincidence probabilities on a three three-dimensional (qutrit) system. We show that this inequality is violated when each observer measures two noncommuting observables, defined by the so-called unbiased six-port beam splitter, on a maximally entangled state of two qutrits. The strength of the violation agrees with the numerical results presented by Kaszlikowski et al, quant-ph/0202019. It is proven that the inequality defines facets of the polytope of local variable models.

Observation of geometric phases for mixed states using NMR interferometry

Examples of geometric phases abound in many areas of physics. They offer both fundamental insights into many physical phenomena and lead to interesting practical implementations. One of them, as indicated recently, might be an inherently fault-tolerant quantum computation. This, however, requires one to deal with geometric phases in the presence of noise and interactions between different physical subsystems. Despite the wealth of literature on the subject of geometric phases very little is known about this very important case. Here we report the first experimental study of geometric phases for mixed quantum states. We show how different they are from the well-understood, noiseless, pure-state case.

Non-linear registration for brain images by maximising feature and intensity similarities with a Bayesian framework

The objective of this work was to provide a new, precise registration of the cortical mantle with a non-linear transformation. Image registration is broadly classified into two types, using intensity similarity and feature similarity. Whereas the former approach has merit in global brain matching, the latter provides a fast registration centred on a region of interest. The hybrid registration proposed in this paper was achieved using a Bayesian framework, which consisted of a likelihood model including intensity similarity and a prior model including feature information and a smoothing constraint. In this approach, each voxel was spatially transformed, so that the distance between corresponding features was shortened and also so that the intensity correlation was maximised. The result of the hybrid method clearly showed a good match of global brain (r = 0.930) by including intensity similarity. Moreover, this method compensated for the approximated sulcus of the feature-based method with intensity information, so that the geometric shape and thickness of the sulcus at the feature-defined region was likely to be registered. The accuracy in the feature-defined area was improved by 33.4% and 7.5% compared with feature-based and intensity-based methods, respectively.

A modified method for intubation of a patient with ankylosing spondylitis using intubating laryngeal mask airway (LMA-Fastrach)--a case report

We present an instance of successful use of an intubating laryngeal mask airway (LMA-Fastrach) and a Cook airway exchanger (CAE) for ventilation and intubation in a patient with severe ankylosing spondilitis (AS) receiving total hip arthroplasty. This measure may serve as an effective alternative for airway management in patients with difficult airway. A 61-year-old male was scheduled for right total hip arthroplasty because of degenerative osteoarthritis. He had been suffering from extensive ankylosing spondylitis, with the cervical spine markedly fixed in anterior flexion. Besides he could not open his mouth widely (35 mm when fully open) also because of ankylosis of jaw. Although we advised an awake fiberoptic tracheal intubation for anesthesia but he refused owing to a previous painful experience. After induction of anesthesia with glycopyrrolate, fentanyl, thiamylal sodium and succinylcholine, we inserted a # 5 Fastrach ILMA for primary airway maintenance. Then through the lumen of the ILMA we introduced the CAE as a guide for endotracheal tube (ETT) intubation. After applying the RAPI-FIT adapter to the CAE, we connected it to the capnography monitor for the confirmation of airway. We finally inserted an endotracheal tube into the trachea using the CAE as a guide. The whole procedure was uneventful and smooth. In sum, the modified Fastrach intubation method may facilitate tracheal intubation in patients with severe ankylosing spondilitis. It may be an alternative way for successful airway management in patients with difficult airway.

Synthesis and biological properties of C-2, C-8, N-9 substituted 6-(3-chloroanilino)purine derivatives as cyclin-dependent kinase inhibitors. Part II

In this study, C-2, C-8, N-9 substituted 6-(3-chloroanilino)purine derivatives were synthesized and their inhibitory effects on cyclin-dependent kinases (CDK2, 4) as well as their cytotoxicities were evaluated. The effects of substituents at the C-2, C-8, and N-9 positions of the substituted purine were investigated. Among the compounds tested, [6-(3-chloroanilino)-2-(2-hydroxymethyl-4-hydroxypyrrolidyl)-9- isopropylpurine] (4h) was the most active inhibitor of CDK2 with IC50 of 0.3 microM, i.e. a two-fold increased inhibitory activity as compared to roscovitine. Results from structure-activity relationship studies should allow the design of more potent and selective CDK2 inhibitors, which may provide an effective therapy for cancer or other CDK-dependant diseases.

Solar damage in skin tumors: quantification of elastotic material

BACKGROUND

The elastotic changes of the dermis are thought to be the primary indicator of the cumulative sun exposure of the dermis. The changes of elastotic material have been evaluated by several previous methods, but these did not quantitatively measure the amount of elastic tissue.

OBJECTIVE

The purpose of this study was to quantify dermal elastosis and to assess the significance of sun exposure in the pathogenesis of nonmelanomatous skin tumors such as basal cell carcinoma (BCC), squamous cell carcinoma (SCC) and Bowen's disease (BD).

METHODS

Ninety-nine sections from biopsy specimens of histopathologically proven BCC, SCC and BD were stained with Verhoeff-van Gieson stains. We studied the amount of elastotic material adjacent to the tumor by image analysis.

RESULTS

There was a 3- to 4-fold increase in the amount of elastotic material in BCC and SCC compared to the sun-exposed skin of normal controls (p < 0.0001). The amount of elastotic material was increased 1.3 times in BD as compared with the nonexposed skins of normal controls (p < 0.01).

CONCLUSION

We demonstrated a quantitative relationship between cumulative solar exposure and skin cancer such as SCC, BCC and BD.

Congenital esophageal stenosis in adults: clinical and radiographic findings in seven patients

OBJECTIVE

The purpose of this study was to determine the clinical and radiographic findings in seven adults with congenital esophageal stenosis.

CONCLUSION

In young or middle-aged individuals, particularly men with long-standing dysphagia, an upper or mid esophageal stricture with multiple ringlike constrictions is a characteristic appearance of congenital esophageal stenosis on double-contrast esophagography.

Quantitative histopathologic findings of erythromelanosis follicularis faciei et colli

BACKGROUND

Even though only 33 cases of Erythromelanosis follicularis faciei et colli (EFFC) have been reported around the world, there have been no quantitative clinicopathological studies yet. The purpose of this study is to examine quantitatively clinical and histopathological evaluations of EFFC using image analysis system.

METHOD

Clinical grading of its severity was assessed. Many parameters of the horny layer, granular layer, epidermis and the dermal components were measured and compared to controls by image analysis. The correlation between the histological findings and clinical grading was assessed.

RESULT

Thickness and compactness of the horny layer was significantly increased in EFFC. There were no significant differences in the number of melanocytes and severity of pigmentation between EFFC and controls; however, melanization was slightly increased in EFFC. The percent area of the superficial blood vessels was significantly increased and correlated with visual grading of erythema. Diameters of hair shafts and outer root sheaths, and thickness of inner root sheaths were decreased. Basal layer pigmentation was correlated with the clinical features of pigmentation.

CONCLUSION

This study supported the findings of hyperkeratosis and dilatation of superficial dermal blood vessels in EFFC. The pigmentation of the basal layer and the percent area of the inner spaces of the superficial dermal blood vessels may reflect the clinical severity more than the other parameters. Although follicular plugging is a characteristic clinical feature of EFFC, enlargement of hair follicles and hair shafts were not characteristic pathologic changes EFFC in our study.