The constrained modified KP hierarchy and the generalized Miura transformations

In this letter, we consider the second Hamiltonian structure of the constrained modified KP hierarchy. After mapping the Lax operator to a pure differential operator the second structure becomes the sum of the second and the third Gelfand-Dickey brackets defined by this differential operator. We simplify this Hamiltonian structure by factorizing the Lax operator into linear terms.Comment: 8 pages, latex, no figure

Large area growth and electrical properties of p-type WSe2 atomic layers.

Transition metal dichacogenides represent a unique class of two-dimensional layered materials that can be exfoliated into single or few atomic layers. Tungsten diselenide (WSe(2)) is one typical example with p-type semiconductor characteristics. Bulk WSe(2) has an indirect band gap (∼ 1.2 eV), which transits into a direct band gap (∼ 1.65 eV) in monolayers. Monolayer WSe(2), therefore, is of considerable interest as a new electronic material for functional electronics and optoelectronics. However, the controllable synthesis of large-area WSe(2) atomic layers remains a challenge. The studies on WSe(2) are largely limited by relatively small lateral size of exfoliated flakes and poor yield, which has significantly restricted the large-scale applications of the WSe(2) atomic layers. Here, we report a systematic study of chemical vapor deposition approach for large area growth of atomically thin WSe(2) film with the lateral dimensions up to ∼ 1 cm(2). Microphotoluminescence mapping indicates distinct layer dependent efficiency. The monolayer area exhibits much stronger light emission than bilayer or multilayers, consistent with the expected transition to direct band gap in the monolayer limit. The transmission electron microscopy studies demonstrate excellent crystalline quality of the atomically thin WSe(2). Electrical transport studies further show that the p-type WSe(2) field-effect transistors exhibit excellent electronic characteristics with effective hole carrier mobility up to 100 cm(2) V(-1) s(-1) for monolayer and up to 350 cm(2) V(-1) s(-1) for few-layer materials at room temperature, comparable or well above that of previously reported mobility values for the synthetic WSe(2) and comparable to the best exfoliated materials

From development zones to edge urban areas in China: A case study of Nansha, Guangzhou City

The new millennium signified a new phase in the development zone-oriented suburbanization of China. Spurred by a new round of urban development strategies, development zones in many large cities face a need for enormous transformations and re-development. These areas have often been compared with the Western concept of “edge cities”, although in this paper we argue that this “imported” concept, in practice, bears little resemblance to the actual development tendencies in China. Taking a comparative approach, this paper presents a critical examination of edge urban formations in the Chinese context, and identifies the major differences between the concept in China and the United States. Drawing upon a case study of Nansha in Guangzhou, the unique paths and underlying dynamics driving these transformations are revealed. It is concluded that Chinese edge urban areas are being transformed from mono-function development zones into new fully functional cities. A city in China like Nansha reveals the dynamics of both state interventions and local actions in boosting the polycentric economies of large city regions

N-(4-Chloro-2-nitro­phen­yl)-5-methyl­isoxazole-4-carboxamide

In the title compound, C11H8ClN3O4, the dihedral angle between benzene and isoxazole rings is 9.92 (1) °. The nitro group is almost coplanar with the benzene ring with an O—N—C—C torsion angle of 8.4 (3)°. The mol­ecular conformation is stabilized by an intra­molecular N—H⋯O hydrogen bond, closing a six-membered ring

N-(2,6-Dichloro­phen­yl)-5-methyl-1,2-oxazole-4-carboxamide monohydrate

In the title compound, C11H8Cl2N2O2·H2O, the dihedral angle between the benzene and isoxazole rings is 59.10 (7)°. In the crystal, the components are linked by N—H⋯O and O—H⋯O hydrogen bonds into a three-dimensional network. The crystal structure is further stabilized by π–π stacking inter­actions [centroid–centroid distance = 3.804 (2) Å]

PRL-3, a Metastasis Associated Tyrosine Phosphatase, Is Involved in FLT3-ITD Signaling and Implicated in Anti-AML Therapy

Combination with other small molecule drugs represents a promising strategy to improve therapeutic efficacy of FLT3 inhibitors in the clinic. We demonstrated that combining ABT-869, a FLT3 inhibitor, with SAHA, a HDAC inhibitor, led to synergistic killing of the AML cells with FLT3 mutations and suppression of colony formation. We identified a core gene signature that is uniquely induced by the combination treatment in 2 different leukemia cell lines. Among these, we showed that downregulation of PTP4A3 (PRL-3) played a role in this synergism. PRL-3 is downstream of FLT3 signaling and ectopic expression of PRL-3 conferred therapeutic resistance through upregulation of STAT (signal transducers and activators of transcription) pathway activity and anti-apoptotic Mcl-1 protein. PRL-3 interacts with HDAC4 and SAHA downregulates PRL-3 via a proteasome dependent pathway. In addition, PRL-3 protein was identified in 47% of AML cases, but was absent in myeloid cells in normal bone marrows. Our results suggest such combination therapies may significantly improve the therapeutic efficacy of FLT3 inhibitors. PRL-3 plays a potential pathological role in AML and it might be a useful therapeutic target in AML, and warrant clinical investigation

(NZ)CH...O Contacts assist crystallization of a ParB-like nuclease

BACKGROUND: The major bottleneck for determination of 3 D structures of proteins using X-rays is the production of diffraction quality crystals. Often proteins are subjected to chemical modification to improve the chances of crystallization RESULTS: Here, we report the successful crystallization of a nuclease employing a reductive methylation protocol. The key to crystallization was the successful introduction of 44 new cohesive (NZ) CH...O contacts (3.2 – 3.7 Å) by the addition of 2 methyl groups to the side chain amine nitrogen (NZ) of 9 lysine residues of the nuclease. The new contacts dramatically altered the crystallization properties of the protein, resulting in crystals that diffracted to 1.2 Å resolution. Analytical ultracentrifugation analysis and thermodynamics results revealed a more compact protein structure with better solvent exclusion of buried Trp residues in the folded state of the methylated protein, assisting crystallization. CONCLUSION: In this study, introduction of novel cohesive (NZ)CH...O contacts by reductive methylation resulted in the crystallization of a protein that had previously resisted crystallization in spite of extensive purification and crystallization space screening. Introduction of (NZ)CH...O contacts could provide a solution to crystallization problems for a broad range of protein targets

Cortical and Subcortical Neural Correlates for Respiratory Sensation in Response to Transient Inspiratory Occlusions in Humans

Cortical and subcortical mechanosensation of breathing can be measured by short respiratory occlusions. However, the corresponding neural substrates involved in the respiratory sensation elicited by a respiratory mechanical stimulus remained unclear. Therefore, we applied the functional magnetic resonance imaging (fMRI) technique to study cortical activations of respiratory mechanosensation. We hypothesized that thalamus, frontal cortex, somatosensory cortex, and inferior parietal cortex would be significantly activated in response to respiratory mechanical stimuli. We recruited 23 healthy adults to participate in our event-designed fMRI experiment. During the 12-min scan, participants breathed with a specialized face-mask. Single respiratory occlusions of 150 ms were delivered every 2–4 breaths. At least 32 successful occlusions were collected for data analysis. The results showed significant neural activations in the thalamus, supramarginal gyrus, middle frontal gyrus, inferior frontal triangularis, and caudate (AlphaSim corrected p < 0.05). In addition, subjective ratings of breathlessness were significantly correlated with the levels of neural activations in bilateral thalamus, right caudate, right supramarginal gyrus, left middle frontal gyrus, left inferior triangularis. Our results demonstrated cortical sources of respiratory sensations elicited by the inspiratory occlusion paradigm in healthy adults were located in the thalamus, supramarginal gyrus, and the middle frontal cortex, inferior frontal triangularis, suggesting subcortical, and cortical neural sources of the respiratory mechanosensation are thalamo-cortical based, especially the connections to the premotor area, middle and ventro-lateral prefrontal cortex, as well as the somatosensory association cortex. Finally, level of neural activation in thalamus is associated with the subjective rating of breathlessness, suggesting respiratory sensory information is gated at the thalamic level

Investigating the kinematics of mountain building in Taiwan from the spatiotemporal evolution of the foreland basin and western foothills

The Taiwanese range has resulted from the collision between the Luzon volcanic arc and the Chinese continental margin, which started about 6.5 Myr ago in the north, and has since propagated southward. The building of the range has been recorded in the spatiotemporal evolution of the foreland basin. We analyze this sedimentary record to place some constraints on the kinematics of crustal deformation. The flexure of the foreland under the load of the growing wedge started with a 1.5 Myr long phase of rapid subsidence and sedimentation, which has migrated southward over the last 3.5 Myr at a rate of 31 +10/−5 mm/yr, reflecting the structural evolution of the range and the growth of the topography during the oblique collision. Isopachs from the Toukoshan (~0 to 1.1 Ma) and Cholan (~1.1 to 3.3 Ma) formations, as well as the sedimentation rates retrieved from a well on the Pakuashan anticline, indicate that the foreland basement has been moving toward the center of mass of the orogen by ~45–50 mm/yr during the development of the basin. From there, we estimate the long-term shortening rate across the range to 39.5–44.5 mm/yr. By considering available data on the thrust faults of the foothills of central Taiwan, we show that most (if not all) the shortening across the range is accommodated by the most frontal structures, with little if any internal shortening within the wedge. The range growth appears therefore to have been essentially sustained by underplating rather than by frontal accretion. In addition, only the upper ~7 to 9 km of the underthrusted crust participates to the growth of the orogen. This requires that a significant amount of the Chinese passive margin crust is subducted beneath the Philippine Sea plate

Expanding the palette of phenanthridinium cations

5,6-Disubstituted phenanthridinium cations have a range of redox, fluorescence and biological properties. Some properties rely on phenanthridiniums intercalating into DNA, but the use of these cations as exomarkers for the reactive oxygen species (ROS), superoxide, and as inhibitors of acetylcholine esterase (AChE) do not require intercalation. A versatile modular synthesis of 5,6-disubstituted phenanthridiniums that introduces diversity by Suzuki–Miyaura coupling, imine formation and microwave-assisted cyclisation is presented. Computational modelling at the density functional theory (DFT) level reveals that the novel displacement of the aryl halide by an acyclic N-alkylimine proceeds by an SNAr mechanism rather than electrocyclisation. It is found that the displacement of halide is concerted and there is no stable Meisenheimer intermediate, provided the calculations consistently use a polarisable solvent model and a diffuse basis set