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The extrapolability of the lysimeter test as a dissipation simulator in an actual paddy field was evaluated using mathematical models and their inverse analyses for predicting pesticide fate and transport processes in paddy test systems. As a source of experimental data, a four-year comparative experiment in lysimeters and paddy fields was conducted using various paddy pesticides. First, the dissipations for various active ingredients in granule pesticides under submerged applications were statistically compared using simple kinetic modeling. Second, the dissipation pathways, unobserved experimental components, and effect of the experimental setting were evaluated using a higher tier mathematical model with a novel inverse analysis protocol. Finally, owing to experimental constraints, the unobtainable parameters were extracted from the laboratory container test before being transferred to compare the outdoor experimental data under different formulation types.

Background Extraction of environmental fate parameters for pesticides by inverse modeling in laboratory experiments has evolved to become a common practice in higher tier exposure modeling. This study focuses on flooded paddy soil conditions using a simple container test system. Four active ingredients of paddy herbicide were tested. The results were parameterized and transferred to analyze the effect of formulation types on the outdoor experimental data via inverse analyses of two structurally-compatible mathematical models, namely: pesticide concentration in paddy field for laboratory (PCPF-LR) and PCPF for outdoors (PCPF-1Rv1.1 ). Results After in-laboratory calibration, the PCPF-LR model revealed statistically acceptable or ideal simulations of pesticide concentrations in both the aqueous and soil phases (e.g. Nash-Sutcliffe efficiency > 0.7), in addition to determining the apparent sorption from the laboratory data. The extracted persistence indicators (degradation half-life, DegT50 ) in the aqueous phase were 1.4-38.7 times higher than those of the dissipation (DT50 ) due to the exclusion of partitioning and phase transfer processes (diffusion and sorption). In the outdoor experiment, 72% of the outdoor-calibrated simulations of the PCPF-1Rv1.1 model, showed statistically acceptable representations of the concentrations in paddy water. Furthermore, the DegT50 as 'bulk' degradation in paddy water was statistically insignificant between the formulation types; however, the DT50 demonstrated statistically different results. Conclusion The laboratory/outdoor data interconnections using proposed modeling approach facilitate the data-specific model calibration and analysis. These can be useful in the exposure modeling of paddy pesticide by manipulating the parameter uncertainties associated with the experimental constraints. © 2020 Society of Chemical Industry.

Comparative experiments investigating the dissipation of four nursery-box-applied pesticides and three foliar-applied pesticides were conducted using lysimeters and in actual paddy fields. In the lysimeter experiments, there were test plots for submerged application for both application types. Analytical concentrations of the pesticides in paddy water were evaluated using appropriate kinetic models. The detection levels of pesticides in the paddy water for the nursery-box and foliar applications were 10–77% and 42–79% of the submerged application, respectively. The times required for 50% dissipation (DT(50)s) in case of the nursery-box and foliar applications were 0.8–10.4 days and 0.5–2.7 days, respectively. Although overall dissipations were affected by the physicochemical properties of the pesticide and the experimental design in the test plots, the initial detection levels in the lysimeters, governed by the runoff at transplanting and the deposition at spraying, were comparable with those in the actual paddy fields.

BACKGROUND In Japan, while experimental data for the dissipation behavior of paddy pesticides under a standardized test system are available, the application of a mathematical model is limited. This paper proposes a new model calibration procedure for inversely deriving the model parameters from the experimental data. This procedure is tested in the open software R by running an improved Pesticide Concentration in Paddy Field-1 (PCPF-1) model with R packages to analyze the dissipation of simetryn and molinate in flooded lysimeters and paddy fields. RESULTS The model fitting was performed by a random minimization routine. Furthermore, the uncertainties of the model parameters envisioned by the global sensitivity analysis were successfully reduced using the Markov chain Monte Carlo technique. The calibrated simulation was validated at each test plot by confirming multiple statistical indices (i.e. Nash-Sutcliffe efficiency 0.88-1.00, percent bias

We show that for an arbitrarily given closed Riemannian manifold $M$ admitting a point $p \in M$ with a single cut point, every closed Riemannian manifold $N$ admitting a point $q \in N$ with a single cut point is diffeomorphic to $M$ if the radial curvatures of $N$ at $q$ are sufficiently close in the sense of $L^1$-norm to those of $M$ at $p$. Our result hence not only produces a weak version of the Cartan--Ambrose--Hicks theorem in the case where underlying manifolds admit a point with a single cut point, but also is a kind of a weak version of the Blaschke conjecture for spheres proved by Berger. In particular that result generalizes one of theorems in Cheeger's Ph.D. Thesis in that case. Remark that every exotic sphere of dimension $> 4$ admits a metric such that there is a point whose cut locus consists of a single point., 16 page, minor corrections and revision

Let $M$ be a connected complete noncompact $n$-dimensional Riemannian manifold with a base point $p \in M$ whose radial sectional curvature at $p$ is bounded from below by that of a noncompact surface of revolution which admits a finite total curvature where $n \geq 2$. Note here that our radial curvatures can change signs wildly. We then show that $\lim_{t\to\infty} \mathrm{vol} B_t(p) / t^n$ exists where $\mathrm{vol} B_t(p)$ denotes the volume of the open metric ball $B_t(p)$ with center $p$ and radius $t$. Moreover we show that in addition if the limit above is positive, then $M$ has finite topological type and there is therefore a finitely upper bound on the number of ends of $M$., 8 pages, minor corrections

This study aimed to develop and validate a Dynamic in-River Agrochemical Fate and Transport (DRAFT) model simulating one-dimensional advective and dispersive pesticide transport processes under unsteady flow regime in a riverine system. The DRAFT model was coupled with two other modeling components, the PCPF-B model and the land use based tank model, which simulated hydrological/pesticide process in paddy fields and hydrological process in other land uses such as city, agricultural field and forest, respectively. The PCPF-B/DRAFT model was fed with the spatial information of the target catchment by incorporating the Geographical Information System (GIS). For the model validation, a full catchment monitoring data of a rice herbicide, mefenacet, along the Kose River, Fukuoka, Japan was utilized. After model calibration, hourly river discharge and daily mefenacet concentration were simulated by the PCPF-B/DRAFT model at individual observed points of the Kose River and model performance was evaluated by graphical assessment and multiple statistical indices (e.g. Nash-Sutcliffe efficiencies were 0.84–0.86 for streamflow and 0.16–0.72 for herbicide, respectively). The predicted mefenacet concentrations were strongly affected by: (1) water managements practiced in rice fields and (2) intensive rainfall events. The former concentrations were characterized by broad peak while for the latter the peak concentration was sharp and narrow. We used the PCPF-B/DRAFT model to further evaluate the applications of 7 days of water holding period after herbicide application in paddy fields, which was shown to effectively reduce the total loss of mefenacet from 18.9 to 12.8% of applied mass. Consequently, the broad peak concentrations of mefenacet in the Kose River decreased remarkably while the water management practice was less effective to reduce the sudden and sharp peak concentration resulting from intensive rainfall events.

Unlike common polyaromatic hydrocarbons, acridine is a characteristic compound bearing both π-stackable large surfaces and a protonable nitrogen atom. Here we report the first synthesis of a supramolecular capsule with multiple acridine panels. In water, the assembly and disassembly of the capsule reversibly occur under neutral and acidic conditions, respectively (≥10 cycles). Notably, the pH-responsive capsule encapsulates a variety of large hydrophobic compounds (up to 1.6 nm in diameter) such as coumarins, metallophthalocyanines and subphthalocyanine in neutral water and subsequently releases them by simple addition of acid.

Three-year comprehensive experiments were conducted to compare the dissipation patterns of a total of 16 pesticides, including 3 metabolites, as granular formulations applied in lysimeters and paddy fields with two soil types. Analytical concentrations of the target pesticides in paddy water were analyzed using a granular kinetic model consisting of the following parameters: release rate, decrease rate, and dissolved concentration. Results of parameter grouping analyses of the kinetic models showed that 56% of data reproducibility (entire grouping) was obtained between replicates for the lysimeters. In comparisons between the lysimeters and paddy fields, 48% of decrease rates and 34% of release rates were grouped, although significant differences were observed with a nearly 90% difference for dissolved concentrations. These differences might be attributed to the hydrological components such as water management and meteorological covariates in paddy fields, the daily percolation in lysimeters and the adsorption-desorption kinetics between paddy water and soil.

In this work, by casting water-soluble ammonium anthracene on metal oxides, the organic surface modifier re-engineered the interface of the metal oxide to improve charge transport. The energy level of ammonium anthracene increased the work function of indium tin oxide (ITO), functioning as a hole-blocker (electron-transporter). Solar cells in which ITO was treated by the ammonium anthracene produced an average power conversion efficiency (PCE) of 5.8% without ZnO, the electron-transporting layer. When the ammonium anthracene was applied to ZnO, an average PCE of 8.1% was achieved, which is higher than the average PCE of 7.5% for nontreated ZnO-based devices.

Metallophthalocyanines (MPcs) are very useful pigments but scarcely soluble without appropriate functional groups in common solvents. Herein, we report that bent polyaromatic amphiphiles act as excellent solubilizing reagents for nonfunctionalized MPcs and larger MPc derivatives (e.g., CuPc, perhalogenated CuPcs, Cu-naphthalocyanine, CuPc polymers, and double-decker MPcs) in neutral water upon encapsulation. The resultant MPc nanocomposites display high stability towards heat and pH change. More importantly, the encapsulated MPcs can be released by simple protocols under mild conditions both into a bulk solvent and onto glass or polymer plates.

A new molecular capsule with a flexible fluorescent shell was formed by the quantitative self-complementary assembly of amphiphilic, U-shaped polyaromatic subunits in water. The capsule can fully encapsulate a variety of non-fluorescent monoterpene compounds (e.g., menthone, menthol, and p-menthane) in the hydrophobic cavity and act as a fluorescent supramolecular probe for recognizing the structural identity of the analytes by emissive signals in water at room temperature.

Nanocarbons are synthetic carbon-rich compounds with polyaromatic frameworks that have lately attracted attention as emerging functional materials. However, their extreme hydrophobicity and aggregation peculiarity, besides their shape and size diversities, precluded their study in solution, especially in "green" water. More convenient and general solubilizing methods of nanocarbon frameworks are required by using non-covalent supramolecular interactions. Here we report a protocol for solubilizing a wide range of nanocarbons, that is, fullerenes (C60 , C70 , C84 , and C120 ), polyarenes (tetracene, pentacene, perylene, coronene, and hexabenzocoronene), and carbon nanotubes (single-walled and multi-walled CNTs), in water through manual grinding with V-shaped polyaromatic amphiphiles. The obtained aqueous nanocomposites are composed of nanocarbons encircled by the polyaromatic frameworks of the amphiphiles through multiple aromatic-aromatic interactions. Notably, the encapsulated photosensitive nanocarbons, such as tetracene, pentacene, and fullerene dimer, exhibit unusual stability toward UV/Vis light.

Spherical molecular assemblies with diameters of ∼2 nm were quantitatively formed in water from new amphiphilic meta-terphenyls with two hydrophilic pendants at the central benzene ring. Whereas intermolecular interactions between small aromatic rings are typically weak, the obtained nanoassemblies are stable enough at wide-ranging concentrations and mostly remain intact even in the presence of similar nanoassemblies with polyaromatic frameworks. The nanoassembly with pentamethyl-substituted terminal benzene rings provides superior host capability for fluorescent dyes in water.

V-shaped polyaromatic amphiphiles with phenanthrene or naphthalene rings spontaneously and quantitatively formed micelle-like nanocapsules in water at room temperature. In contrast to usual polyaromatic aggregates with weak fluorescent properties, the new capsules providing spherical polyaromatic shells with diameters of ∼2 nm show strong fluorescent emissions due to an aggregation-induced enhanced emission (AIEE) effect and moreover encapsulate a fluorescent coumarin dye to generate highly emissive host-guest composites.

Micelles are a versatile class of molecular assemblies typically composed of aliphatic molecules with hydrophilic groups. Polyaromatic molecules with hydrophilic groups, on the other hand, usually do not assemble into micellar structures in water but rather form columnar, π-stacked architectures. This Minireview article focuses on the recent development of aqueous micellar nanostructures with multiple oligoarylene rods or polyaromatic panels. The new micelles with spherical polyaromatic shells, which we name "aromatic micelles", serve as functional molecular flasks with superior binding abilities for medium to very large molecules in water.

Functionalization of the polyaromatic shell of a micelle-like molecular capsule was accomplished by simple functionalization of the amphiphilic subunits composed of a bent bis-anthracene framework and two trimethylammonium groups. In aqueous solutions, functionalized subunits assemble spontaneously and quantitatively into spherical capsules providing anthracene shells with external diameters of 2–3 nm through hydrophobic and aromatic-aromatic interactions. The shape and size of the functionalized capsules remain similar to the original, but the emissive intensities increase significantly (up to 5-fold) by attaching cyano or phenylethynyl groups. Furthermore, the shell-functionalization drastically enhances the host–guest photophysical properties (up to 8-fold) in the cavities of the capsules, as estimated by emission intensities from the encapsulated fluorescent dyes.

Soft tissue angiofibroma (STA), a recently suggested new histologic entity, is a benign fibrovascular soft tissue tumor composed of bland spindle-shaped tumor cells with abundant collagenous to myxoid stroma and branching small vessels. The lesion has a characteristic AHRR-NCOA2 fusion gene derived from chromosomal translocation of t(5;8)(p15;q13). However, morphologically similar tumors containing abundant fibrovascular and myxoid stroma can complicate diagnosis. We designed an original DNA probe for detecting NCOA2 split signals on fluorescence in situ hybridization (FISH) and estimated its utility with 20 fibrovascular tumors: 4 each of STAs, solitary fibrous tumors (SFTs), and cellular angiofibromas and 3 each of low-grade myxofibrosarcomas, myxoid liposarcomas, and low-grade fibromyxoid sarcomas. We also performed FISH for 13q14 deletion and immunohistochemistry (IHC) staining for estrogen receptor, progesterone receptor, retinoblastoma protein, and MUC-4 expression. Furthermore, IHC for Stat6 was conducted in the 20 cases analyzed by FISH and in an additional 26 SFTs. We found moderate to strong nuclear Stat6 expression in all SFTs but no expression in the other tumors. Both estrogen receptor and progesterone receptor expressions were observed in STAs, SFTs, and cellular angiofibromas. Expression of retinoblastoma protein was found in less than 10% of cells in all tumor types except myxoid liposarcoma. The low-grade fibromyxoid sarcomas were strongly positive for MUC-4. All STAs showed NCOA2 split signals on FISH. All tumors, regardless of histologic type, had 13q14 deletion. The NCOA2 FISH technique is a practical method for confirming STA diagnosis. The combination of NCOA2 FISH and Stat6 IHC proved effective for the differential diagnosis of STA, even when using small biopsy specimens.

Perpendicular spin-transfer-torque magnetic random access memory (p-STT-MRAM) is a promising candidate memory device for replacing dynamic random access memory (DRAM) facing with 10-nm sub scaling down. In addition to scaling down, p-STT MRAM has many advantages like fast write/read speed (~10ns) as DRAM, low power consumption (1014), and non-volatility (retention time > 10 years). But to replace DRAM, there are several challenges to be solved. First, high tunneling magneto-resistance (TMR) ratio for read sensing margin. Second, low critical current density(J C) for low power consumption. Third, thermal stability(Δ) for long retention time to save data. And also these parameters should be achieved at 350oC annealing temperature of the back-end-of line (BEOL) to be commercialized. Among them, thermal stability is closely related with cell size. As a cell size of MTJ decreases to achieve a high density memory device, thermal stability decreases with retention time, thus it is not easy to implement both high density and non-volatile memory device simultaneously by decreasing the cell size of MTJ. In our study to solve this issue, we propose the p-STT multi-level cell (MLC) magnetic tunnel junction (MTJ) because MLC MTJ can satisfy both high density and non-volatile memory device at the same time. In particular, we design the MTJ structure with dual free layers and MgO tunnel barriers, so that the MTJ can demonstrate four resistance states. In addition, we investigated the effect of the thickness of two free layers and MgO tunnel barriers on two magneto-resistance (MR) and switching voltage. In our experiments, the p-STT MTJ spin-valves were fabricated on 12-inch-diameter Si/ SiO2/W/TiN wafers by utilizing a 12-in. multi-chamber-cluster magnetron-sputtering system under a high vacuum (less than 110-8 Torr) without breaking the vacuum. Then, all samples were subject to ex-situ annealing at 350℃ at a back end of line (BEOL) for 30 minutes under a magnetic field of 3 tesla. In our presentation, we present how to optimize the thicknesses of two free layers and MgO tunnel barriers. In addition, we repot how the magnetic behavior and the resistance of MTJ is affected by magnetic and how the magneto-resistance of MTJ is closely related to the crystallinity of two MgO tunnel barriers. Acknowledgements This work was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIP) (No. 2017R1A2A1A05001285)

This paper demonstrates the procedures for probabilistic assessment of a pesticide fate and transport model, PCPF-1, to elucidate the modeling uncertainty using the Monte Carlo technique. Sensitivity analyses are performed to investigate the influence of herbicide characteristics and related soil properties on model outputs using four popular rice herbicides: mefenacet, pretilachlor, bensulfuron-methyl and imazosulfuron. Uncertainty quantification showed that the simulated concentrations in paddy water varied more than those of paddy soil. This tendency decreased as the simulation proceeded to a later period but remained important for herbicides having either high solubility or a high 1st-order dissolution rate. The sensitivity analysis indicated that PCPF-1 parameters requiring careful determination are primarily those involve with herbicide adsorption (the organic carbon content, the bulk density and the volumetric saturated water content), secondary parameters related with herbicide mass distribution between paddy water and soil (1st-order desorption and dissolution rates) and lastly, those involving herbicide degradations.

We investigate the finiteness structure of a complete non-compact $n$-dimensional Riemannian manifold $M$ whose radial curvature at a base point of $M$ is bounded from below by that of a non-compact von Mangoldt surface of revolution with its total curvature greater than $\pi$. We show, as our main theorem, that all Busemann functions on $M$ are exhaustions, and that there exists a compact subset of $M$ such that the compact set contains all critical points for any Busemann function on $M$. As corollaries by the main theorem, $M$ has finite topological type, and the isometry group of $M$ is compact., Comment: This version 2 is a version to appear in Math. Ann. 16 pages, No figures

Perpendicular spin-transfer-torque magnetic random access memory (p-STT MRAM) cells consist of a perpendicular magnetic tunnel junction and a selective device has been researched intensively because of the possibility of overcoming the scaling limitations of the current dynamic random access memory (DRAM) below the 10-nm design rule [1]. p-STT-MRAM requires high tunneling magnetoresistance (TMR) ratio greater than 150%, sufficient thermal stability (Δ=KuV/kBT) above 75 for a ten-year retention-time, and low switching current (J C0 ~ 1 MA/cm2) must be achieved for low power consumption [2-3]. However, the thermal stability is hard to maintain when scaling down in 10-nm scale of the p-STT MRAM cells for terabit integration. It requires high interfacial anisotropy K i to maintain the thermal stability requirement for 10-year retention time [4]. In this study, we designed a p-MTJ spin-valve with a double pinned structure to realize two-bit operation to secure a larger scaling limit (see Fig. 1(a)). We investigated the dependency of the number of [Co/Pt]n multilayers on the coupling strength to the pinned layers in order to control the spin-electron direction of the pinned layers. The total number of [Co/Pt]n SyAF multilayers ferro-coupled to the bottom pinned layer was reduced from 9 to 3 layers to reduce the roughness of the MgO tunneling barrier to increase the TMR ratio. Also, the number of [Co/Pt]n of the top upper SyAF multilayers was modulated so that the coercive field (H c) required to switch the spin-electron direction of the top pinned layer increased from about 0.3 kOe to 1 kOe which is sufficient to ensure the memory margin for two-bit operation, as shown in Fig. 1(b). Then, we investigated the multiple resistance states with the R-H loop of the double pinned p-MTJ spin-valve, as shown in Fig. 1(c). It showed four different resistance states depending on the spin-electron direction of the free layers and pinned layers as shown in Fig. 1(d) with a maximum TMR ratio of 166%. This implies that the double pinned p-MTJ spin-valve may be suitable for terabit integration compared to that of the single-bit operating p-STT MRAM memory cells. Acknowledgements This work was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIP) (No.2017R1A2A1A05001285) and Brain Korea 21 PLUS Program in 2014. References [1] K. C. Chun et al., IEEE J. Solid-st. Circ. 48, 598 (2013) [2] J. G. Park et al., IEEE Int. Electron Devices Meeting, IEDM 2015–February, 19.2.1-19.2.4 (2015). [3] Amiri, P.K., et al., App. Phys. Lett. 98, 112507 (2011) [4] Shouzhong Peng, et al., IEEE MAGNETICS LETTERS, volume 8 (2017). Figure 1

Recently, dynamic random access memory (DRAM) has scaling limit because of its capacitor area. To replace DRAM, the next generation memory devices are being studied. Among them, perpendicular spin transfer torque magnetic random access memory (p-STT MRAM) is considered as a promising candidate because of easy scaling down, low power consumption, high read and write speed and non-volatility. p-STT MRAM has several challenges for commercialization. To keep a high retention time (~10 years), STT-MRAM should have thermal stability greater than 74. Although the thickness of free layer is increased with thermal stability, the thickness of free layer is limited to maintain perpendicular magnetic anisotropy (PMA). One of studies, double MgO based p-MTJ spin-valve structure is issued for its large volume because in case of double MgO based p-MTJ spin-valve, PMA of the free layer is originated from two i-PMA between the CoFeB free layer / MgO tunneling barrier and CoFeB free layer / MgO capping layer. The i-PMA induced from the two interfaces increases the total volume of the magnetic free layer which increases the thermal stability, but it is still limited by the thickness of the individual CoFeB free layers. In our study, therefore, we propose a new structure using interfacial Co2Fe6B2 and [Co/Pt]n multi-layer as bulk PMA to achieve higher thermal stability than that of double MgO based p-MTJ spin-valve structure. The dependence of the magnetic moment and thermal stability on the number of [Co/Pt]n multi-layers was estimated by using vibrating sampling magnetometer (VSM) as shown in Fig.1 b. Magnetic moment t~180μemu/cm2) of i-PMA+[Co/Pt]2 multi-layers is similar to that(~180μemu/cm2) of double MgO based p-MTJ spin-valve structure. Also, magnetic moment (t~366μemu/cm2) of i-PMA+ [Co/Pt]5 multi-layers is about two times more than that of double MgO based p-MTJ spin-valve structure and thermal stability (~181) is two times higher than that (~74) of the double MgO based p-MTJ spin-valve structure. The thermal stability can be modulated by simply changing the number of [Co/Pt]n multi-layers. Obviously, these results show that i-PMA + [Co/Pt]n multilayer as bulk PMA based p-MTJ spin-valve can achieve a high thermal stability. In our presentation, we report the different characteristics of the p-MTJ spin-valve with [Co/Pt]n multi-layers by examining the static magnetization behavior, TMR ratio and MgO crystallinity. In addition, we present how these properties influence mechanism of p-MTJ spin-valve. Acknowledgements This work was supported by a Basic Science Research Program grant from the National Research Foundation of Korea (NRF) funded by the Korean government (MSIP) (No. 2017R1A2A1A05001285) and the Brain Korea 21 PLUS Program in 2014. Figure 1

We investigate the topology of a complete Riemannian manifold whose radial curvature at the base point is bounded from below by that of a von Mangoldt surface of revolution. Sphere theorem is generalized to a wide class of metrics, and it is proven that such a manifold of a noncompact type has finitely many ends.

We investigated the significance of endogenous reactive oxygen species (ROS) produced by fungi treated with miconazole. ROS production inCandida albicanswas measured by a real-time fluorogenic assay. The level of ROS production was increased by miconazole at the MIC (0.125 μg/ml) and was enhanced further in a dose-dependent manner, with a fourfold increase detected when miconazole was used at 12.5 μg/ml. This increase in the level of ROS production was completely inhibited by pyrrolidinedithiocarbamate (PDTC), an antioxidant, at 10 μM. In a colony formation assay, the decrease in cell viability associated with miconazole treatment was significantly prevented by addition of PDTC. Moreover, the level of ROS production by 10 clinical isolates ofCandidaspecies was inversely correlated with the miconazole MIC (r= −0.8818;P< 0.01). These results indicate that ROS production is important to the antifungal activity of miconazole.

Spaces with radially symmetric curvature at base point p are shown to be diffeomorphic to space forms. Furthermore, they are either isometric to R n or S n under a radially symmetric metric, to RP n with Riemannian universal covering of S n equipped with a radially symmetric metric, or else have constant curvature outside a metric ball of radius equal to the injectivity radius at p.

Recently, perpendicular-spin-transfer torque magnetic random access memory (p-STT MRAM) has received considerable attention as the next-generation memory referred from its pre-eminent characteristics. It has high speed writing and reading property like dynamic random access memory (DRAM) with an additional property of non-volatility. Furthermore, it also has stable endurance (> 1014), less electric energy consumption to maintain its data (~1 pJ/bit) and high scalability. Because of these properties, p-STT MRAM has been considered to be the universal memory that can replace other memories in the market. However, it is difficult to be commercialized due to many critical issues of device parameters i.e., the tunneling magnetoresistance (TMR) ratio, thermal stability (Δ), and switching current density (JC). In particular, theses three device parameters should be achieved at 400oC temperature of the back-end of line (BEOL) to be manufactured into the market. To gain a reputation as a non-volatile memory at the market, p-STT MRAM needed low switching current density for low-power operating device. In our research, we investigated new MTJ structure using single MgO based double Co2Fe6B2free layers separated by a W spacer layer (See Fig.1) for low current switching. Samples were made by utilizing 12-inch multi-chamber magnetron sputtering system and magnetic vacuum oven. After sputtering process, samples were ex-situ annealed at 350 or 400oC under a perpendicular magnetic field of 3T for 30 minutes. Figure 2 shows the switching voltage of anti-parallel state to parallel state (AP-P) and parallel state to anti-parallel state (P-AP) on I-V measurement. The switching voltage of AP-P and P-AP at newly double free layer decreased about 3.8 and 5.2% respectively, compared with the conventional free layer. This means that upper Co2Fe6B2 free layer had an influence for the lower Co2Fe6B2 free layer, therefor the lower Co2Fe6B2free-layer easily switched to perpendicular direction by in-plane magnetic anisotropy (IMA) magnetic resonance coupling. In our presentation, we will present the switching property of Co2Fe6B2 double free layer for p-MTJs and review the switching mechanism for IMA magnetic resonance coupling by using IV measurement. In addition, we review the magnetic properties, atomic composition and TMR ratio, by using vibrating-sampling-magnetometer (VSM), Secondary-Ion-Mass-Spectrometry (SIMS), current-in–plane-tunneling (CIPT) measurement respectively. * This work was supported by a Basic Science Research Program grant from the National Research Foundation of Korea (NRF) funded by the Korean government (MSIP) (No. 2014R1A2A1A01006474) and the Brain Korea 21 PLUS Program in 2014. Figure 1

As our main theorem, we prove that a Lipschitz map from a compact Riemannian manifold $M$ into a Riemannian manifold $N$ admits a smooth approximation via immersions if the map has no singular points on $M$ in the sense of F.H. Clarke, where $\dim M \leq \dim N$. As its corollary, we have that if a bi-Lipschitz homeomorphism between compact manifolds and its inverse map have no singular points in the same sense, then they are diffeomorphic. We have three applications of the main theorem: The first two of them are two differentiable sphere theorems for a pair of topological spheres including that of exotic ones. The third one is that a compact $n$-manifold $M$ is a twisted sphere and there exists a bi-Lipschitz homeomorphism between $M$ and the unit $n$-sphere $S^n(1)$ which is a diffeomorphism except for a single point, if $M$ satisfies certain two conditions with respect to critical points of its distance function in the Clarke sense. Moreover, we have three corollaries from the third theorem; the first one is that for any twisted sphere $\Sigma^n$ of general dimension $n$, there exists a bi-Lipschitz homeomorphism between $\Sigma^n$ and $S^n(1)$ which is a diffeomorphism except for a single point. In particular, there exists such a map between an exotic $n$-sphere $\Sigma^n$ of dimension $n>4$ and $S^n(1)$; the second one is that if an exotic $4$-sphere $\Sigma^4$ exists, then $\Sigma^4$ does not satisfy one of the two conditions above; the third one is that for any Grove-Shiohama type $n$-sphere $N$, there exists a bi-Lipschitz homeomorphism between $N$ and $S^n(1)$ which is a diffeomorphism except for one of points that attain their diameters., Comment: 39 pages, no figures, minor corrections

A sensitive method was developed for determination of n-hexane and cyclohexane in human body fluids by headspace capillary gas chromatography (GC) with cryogenic oven trapping. Whole blood and urine samples containing n-hexane and cyclohexane were heated in a 7.5 mL vial at 70°C for 15 min, and 5 mL of the headspace vapor was drawn into a glass syringe. All vapor was introduced through an injection port of a GC instrument in the splitless mode into an Rtx-Volatiles middle-bore capillary column at an oven temperature of −40°C for trapping volatile compounds. The oven temperature was programmed to 180°C for GC with flame ionization detection. These conditions gave sharp peaks for both n-hexane and cyclohexane, a good separation of each peak, and low background impurities for whole blood and urine. The extraction efficiencies of n-hexane and cyclohexane were 13.2–30.3% for whole blood and 12.7–20.7% for urine. The coefficients of within-day variation in terms of extraction efficiency of both compounds were 5.0–9.5% for whole blood and 3.8–10.8% for urine; those of day-to-day variationfor the compounds were not greater than 16.6%. The regression equations for n-hexane and cyclohexane showed good linearity in the range of 5–500 ng/0.5 mL for whole blood and urine. The detection limits (signal-to-noise ratio = 3) for both compounds were 1.2 and 0.5 ng/0.5 mL for whole blood and urine, respectively. The data on n-hexane or cyclohexane in rat blood after inhalation of each compound are also presented.

Eight triazine herbicides, prometon, propazine, atrazine, simazine, prometryn, ametryn, metribuzin, and cyanazine, have been extracted from human whole blood and urine samples by headspace solid-phase microextraction (SPME) with a polydimethylsiloxane-coated fiber and quantified by capillary gas chromatography with nitrogen-phosphorus detection.

An improved method for extraction of thinner components in human whole blood and urine samples by headspace solid-phase microextraction (SPME) with a Carboxen/polydimethylsiloxane-coated fiber is presented. The body fluid samples, containing ethyl acetate, benzene, 1-butanol, toluene, butyl acetate, isoamyl acetate and ethylbenzene as internal standard (IS), were heated at 70 degrees C in a silicone-rubber septum-capped vial in the presence of distilled water plus NaCl; a Carboxen/polydimethylsiloxane-coated SPME fiber was then exposed to the headspace of the vial to allow adsorption of the compounds before capillary gas chromatography (GC) with flame-ionization detection. For whole blood, extraction efficiencies of 1-butanol, ethyl acetate and isoamyl acetate were 8.72-31.1%, and those of IS, butyl acetate, toluene and benzene were 42.9-74.1%. For urine, those of all compounds were 10.7-75.4%. The regression equations for six thinner components extracted from whole blood and urine were linear in the range of 3-500 ng/0.5 ml for ethyl acetate and 1-butanol, and 0.5-500 ng/0.5 ml for benzene, toluene, butyl acetate and isoamyl acetate. The detection limits for each of the components were 0.25-1.5 ng/0.5 ml for both samples. The coefficients of within-day and day-to-day variation for all components were satisfactory and not greater than 11 and 13%, respectively. The data obtained from actual determination of ethyl acetate, benzene and toluene in rat whole blood and urine after inhalation of the compounds were also presented.

Methanol and its metabolite formic acid have been found extractable from human whole blood and urine by headspace solid-phase microextraction (SPME) with a Carboxen/polydimethylsiloxane fiber. The headspace SPME for formic acid was carried out after derivatization to methyl formate under acidic conditions. The determinations of both compounds were made by using acetonitrile as internal standard (IS) and capillary gas chromatography (GC) with flame ionization detection. The headspace SPME-GC gave sharp peaks for methanol, methyl formate and I.S.; and low background noises for whole blood and urine samples. Extraction efficiencies were 0.25-1.05% of methanol and 0.38-0.84% formic acid for whole blood and urine. The calibration curves for methanol and formic acid showed excellent linearity in the range of 1.56 to 800 and 1.56 to 500 microg/0.5 ml of whole blood or urine, respectively. The detection limits were 0.1-0.5 microg/0.5 ml for methanol and 0.6 microg/0.5 ml for formic acid for both body fluids. The within-day relative standard deviations in terms of extraction efficiency for both compounds in whole blood and urine samples were not greater than 9.8%. By using the established SPME method, methanol and formic acid were successfully separated and determined in rat blood after oral administration of methanol.

We will construct surfaces of revolution with finite total curvature whose Gauss curvatures are not bounded. Such a surface of revolution is employed as a reference surface of comparison theorems in radial curvature geometry. Moreover, we will prove that a complete non-compact Riemannian manifold M is homeomorphic to the interior of a compact manifold with boundary, if the manifold M is not less curved than a non-compact model surface of revolution, and if the total curvature of the model surface is finite and less than $2\pi$. Hence, in the first result mentioned above, we may treat a much wider class of metrics than that of a complete non-compact Riemannian manifold whose sectional curvature is bounded from below by a constant., Comment: Change in title. This v3 is a version to appear in Nagoya Mathematical Journal. 10 pages, no figures

A simple catalyst system, obtained by mixing of Ir2Cl2(cod)2 with diphosphine ligands in situ, allows for efficient preparation of pyridine derivatives from nitriles and alkynes.

A series of heterocyclic organobismuth(III) carboxylates 4 and 5 [RCO2Bi(C6H4-2-SO2C6H4-1′-)] derived from diphenyl sulfone was synthesized to determine the influence of the carboxylate ligand structure on the lipophilicity and antifungal activity against the yeast Saccharomyces cerevisiae. In contrast to the clear structure–activity relationship between the size of the inhibition zone and the value of ClogP for specific substitution on diphenyl sulfone scaffold 1 [ClBi(5-RC6H3-2-SO2C6H4-1′-)], scaffolds 4 and 5 showed similar inhibition activities irrespective of the ClogP value. This suggests that these molecules function inside the yeast cell by separating into the cationic heterocyclic bismuth scaffold and the anionic carboxylate moiety, and that the bismuth scaffold plays an important role in the inhibition activity.

A new salt-[Ni(II)(DMSO)(5)(TTFPy)](2)[α-SiW(12)O(40)] (1)-based on polyoxometalates was prepared by coordinating a cationic electron donor of pyridyltetrathiafulvalene (TTFPy) with Ni(II). Although the TTFPy molecule did not form a salt with the anionic α-[SiW(VI)(12)O(40)](4-) because of the weak charge-transfer (CT) interaction, the coordination of Ni with the pyridyl moiety permitted salt formation driven by electrostatic interaction, giving a single crystal of 1. Crystallographic analysis, UV-vis and IR spectroscopy and electrochemical characterization revealed that the fully oxidized α-[SiW(VI)(12)O(40)](4-) was crystallized with the neutral TTFPy moiety from the acetonitrile solution because of the low electron-withdrawing ability of α-[SiW(VI)(12)O(40)](4-), forming a brown-orange crystal. The crystal colour quickly turned to black by immersing in methanol, due to CT from TTF moiety to α-[SiW(VI)(12)O(40)](4-), which was caused by the solvent effect. Increase in the solvent acceptor number from 18.9 for acetonitrile to 41.3 for methanol resulted in the enhancement of the electron withdrawing ability of α-[SiW(VI)(12)O(40)](4-) by 0.317 V in methanol.