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Vision Transformer (ViT) is becoming more and more popular in the field of image processing. This study aims to improve the robustness against the unknown perturbations without retraining the ViT model from scratch. Since our approach does not alter the training phase, it does not need to repeat computationally heavy pretraining of ViT. Specifically, we use test-time adaptation (TTA) for this purpose, which corrects its prediction during test-time by itself. The representative test-time adaptation method, Tent, is recently found to be applicable to ViT by modulating parameters and gradient clipping. However, we observed that Tent sometimes catastrophically fails, especially under severe perturbations. To stabilize the adaptation, we propose a new loss function called Attent, which minimizes the distributional differences of the attention entropy between the source and target. Experiments of image classification task on CIFAR-10-C, CIFAR-100-C, and ImageNet-C show that both Tent and Attent are effective on a wide variety of corruptions. The results also show that by combining Attent and Tent, the classification accuracy on corrupted data is further improved.

Sequential variational autoencoders (VAEs) with a global latent variable z have been studied for disentangling the global features of data, which is useful for several downstream tasks. To further assist the sequential VAEs in obtaining meaningful z, existing approaches introduce a regularization term that maximizes the mutual information (MI) between the observation and z. However, by analyzing the sequential VAEs from the information-theoretic perspective, we claim that simply maximizing the MI encourages the latent variable to have redundant information, thereby preventing the disentanglement of global features. Based on this analysis, we derive a novel regularization method that makes z informative while encouraging disentanglement. Specifically, the proposed method removes redundant information by minimizing the MI between z and the local features by using adversarial training. In the experiments, we trained two sequential VAEs, state-space and autoregressive model variants, using speech and image datasets. The results indicate that the proposed method improves the performance of downstream classification and data generation tasks, thereby supporting our information-theoretic perspective for the learning of global features.

Lead halide perovskite solar cells (PSCs) with a structure of glass/FTO/TiO2/CH3NH3PbI3 with single-walled carbon nanotubes (SWNT) as the transparent top electrodes, followed by polymethyl methacrylate (PMMA) over-coating were fabricated. The SWNT-based PSCs do not require expensive metal electrodes and hole-transporting materials yet produce a decent power conversion efficiency of 11.8%, owing to the densifying effect of SWNTs by PMMA. The resulting devices demonstrate reduced hysteresis, improved stability, and increased power conversion efficiency.

This study aimed to examine the influence of immediate loading on the dynamic changes of bone metabolism around dental implants using a high-resolution semiconductor sodium 18F-fluoride (Na18F)-PET. Tibiae of 12 adult male rats were divided into 4 groups: immediate loading (IL), no loading (NL), bone defect (BD), and control (CTR). For the IL group, a 4.0-N load was applied continuously by two closed-coil springs attached between two implants in tibia. Each rat received an intravenous injection of Na18F and was scanned by high-resolution Na18F-PET at day 1 and then at weeks 1, 2, 3, 4, 5, 6, and 8 after surgery. Bone metabolism around the implant was evaluated by standardized uptake value (SUV), which indicates the outcome of Na18F accumulation. CT scanning was also performed, and PET and CT images were superposed to determine the anatomical orientation in PET images. Bone metabolism peaked at 7 days after surgery and then gradually decreased in all three test groups (IL, NL, and BD). SUVs of all three test groups were significantly higher than the baseline at 1, 2, 3, and 4 weeks after surgery, with SUVs in the IL group returning to baseline levels earlier than those in the NL and BD groups. Fluorine integrates preferentially with the initial low-calcified bone; thus, our results suggest that immediate loading promotes the calcification of the bone tissue in the early stage on peri-implant bone formation. Na18F-PET allows for an estimate of bone metabolism change around the implant.

Instanton partition functions of $\mathcal{N}=1$ 5d Super Yang-Mills reduced on $S^1$ can be engineered in type IIB string theory from the $(p,q)$-branes web diagram. To this diagram is superimposed a web of representations of the Ding-Iohara-Miki (DIM) algebra that acts on the partition function. In this correspondence, each segment is associated to a representation, and the (topological string) vertex is identified with the intertwiner operator constructed by Awata, Feigin and Shiraishi. We define a new intertwiner acting on the representation spaces of levels $(1,n)\otimes(0,m)\to(1,n+m)$, thereby generalizing to higher rank $m$ the original construction. It allows us to use a folded version of the usual $(p,q)$-web diagram, bringing great simplifications to actual computations. As a result, the characterization of Gaiotto states and vertical intertwiners, previously obtained by some of the authors, is uplifted to operator relations acting in the Fock space of horizontal representations. We further develop a method to build qq-characters of linear quivers based on the horizontal action of DIM elements. While fundamental qq-characters can be built using the coproduct, higher ones require the introduction of a (quantum) Weyl reflection acting on tensor products of DIM generators., 42 pages

The pages and hyperlinks of the World Wide Web may be viewed as nodes and edges in a directed graph. In this paper, we propose a new definition of the distance between two pages, called average-clicks. It is based on the probability to click a link through random surfing. We compare the average-clicks measure to the classical measure of clicks between two pages, and show the average-clicks fits better to the users' intuition of distance.

Organic solar cells (OSCs) offer the possibility of harnessing the sun's ubiquitous energy in a low-cost, environmentally friendly and renewable manner. OSCs based on small molecule semiconductors (SMOSCs) – have made a substantial improvement in recent years and are now achieving power conversion efficiencies (PCEs) that match those achieved for polymer:fullerene OSCs. To date, all efficient SMOSCs have relied on the same fullerene acceptor, PCBM, in order to achieve high performance. The use of PCBM however, is unfavourable due to its low lying LUMO level, which limits the open-circuit voltage (VOC). Alternative fullerene derivatives with higher lying LUMOs are thus required to improve the VOC. The challenge, however, is to prevent the typical concomitant decrease in the short circuit current density (JSC) when using a higher LUMO fullerene. In this communication, we address the issue by applying methano indene fullerene, MIF, a bis-functionalised C60 fullerene that has a LUMO level 140 mV higher than PCBM, in solution processed SMOSCs with a well known small molecule donor, DPP(TBFu)2. MIF-based devices show an improved VOC of 140 mV over PC61BM and only a small decrease in the JSC, with the PCE increasing to 5.1% (vs. 4.5% for PC61BM).

We diagonalize the Hilbert space of some subclass of the quasifinite module of the \Winf algebra. States are classified according to their eigenvalues for infinitely many commuting charges and the Young diagrams. The parameter dependence of their norms is explicitly derived. The full character formulae of the degenerate representations are given as summation of the bilinear combinations of the Schur polynomials.

We study quasifinite highest weight modules over the supersymmetric extension of the $W_{1+\infty}$ algebra on the basis of the analysis by Kac and Radul. We find that the quasifiniteness of the modules is again characterized by polynomials, and obtain the differential equations for highest weights. The spectral flow, free field realization over the $(B,C)$--system, and the embedding into $\Glinf$ are also presented.

Gastric mucosal lesions are an important complication in endotoxemia. In order to define the role played by the vagus nerve and endothelial-derived relaxing factor (EDRF) in gastric mucosal blood flow, an investigation was carried out on four groups of rats: a control group; a group given lipopolysaccharide (LPS, 5 mg/kg); a group given gossypol-acetic acid (gossypol), which has an injurious effect on the vascular endothelial cell; and a group given L-NG-monomethyl arginine (LNMMA). Following the administration of acetylcholine and papaverine hydrochloride (via the splenic artery) and vagus nerve stimulation in all four groups of rats, the effects of vagus nerve stimulation and EDRF on the gastric mucosal blood flow were determined with a laser Doppler rheometer. In the LPS group, the gastric mucosal blood flow was decreased after acetylcholine administration and vagus nerve stimulation. This was also the case in the gossypol group. These findings suggest that inhibition of EDRF release may be responsible for the reduced gastric mucosal blood flow observed in endotoxemia.

We show that Nekrasov instanton partition function for SU(N) gauge theories satisfies recursion relations in the form of U(1)+Virasoro constraints when {\beta} = 1. The constraints give a direct support for AGT conjecture for general quiver gauge theories., Comment: 23 pages, 7 figures. v2: typos corrected

Motivated by application to multiple M5 branes, we study some properties of non-Abelian two-form gauge theories. We note that the fake curvature condition which is commonly used in the literature would restrict the dynamics to be either a free theory or a topological system. We then propose a modification of transformation law which simplifies the gauge transformation of 3-form field strength and enables us to write down a gauge invariant action. We then argue that a generalization of Stueckelberg mechanism naturally gives mass to the two-form gauge field. For the application to multiple M5-branes, it should be identified with the KK modes., 21 pages

This article describes design of fullerene-based electron-accepting materials to obtain high performance in organic thin-film photovoltaic devices. A 1,4-bis(dimethylphenylsilylmethyl)[60]fullerene gives higher open circuit voltage than 1,2-diadduct because of smaller π-conjugated systems, and enables columnar fullerene-core array for high electron mobility and thermal crystallization for ideal phase separation with electron-donor materials. A 56π-electron fullerene derivative possessing the dihydromethano group as the smallest carbon addend does not disrupt fullerene-fullerene contact in solid state, giving high open-circuit voltage without decreasing of short-circuit current density and fill factor.

Serum gastrin levels in 44 peptic ulcer patients (26 gastric ulcer patients and 18 duodenal ulcer patients) were determined after they had been treated with omeprazole (OPZ) (20 mg/day) alone or in combination with pirenzepine (PZP) (100 mg/day). Serum gastrin levels were measured before, as well as 2, 4 and 6 weeks after administration, and the changes were compared. The levels were significantly elevated (twofold) at 2 weeks of treatment in both the OPZ and OPZ plus PZP groups. In patients taking OPZ alone, the levels rose up to 6 weeks, while in those taking OPZ plus PZP the levels decreased at 4 and 6 weeks. At 4 weeks, serum gastrin levels in the OPZ plus PZP group were lower (although not significantly) than those in patients taking OPZ alone. In gastric ulcer patients, serum gastrin levels in the OPZ group were significantly elevated, while in the OPZ plus PZP group, these levels were only slightly, but not significantly elevated. There was no significant difference between the two gastric ulcer groups at any time. In duodenal ulcer patients, serum gastrin levels increased significantly at 2 weeks of treatment in both groups. At 4 weeks and thereafter, the serum gastrin levels remained significantly high in patients taking OPZ alone, while they decreased at both 4 and 6 weeks in patients taking OPZ plus PZP. Thus, serum gastrin levels in duodenal ulcer patients were markedly decreased by the addition of PZP. These results demonstrate that PZP inhibits the increase in serum gastrin levels induced by OPZ, and suggest that PZP may suppress the rebound hyperacidity that occurs after treatment with OPZ, thus preventing ulcer recurrence.

The charge transport properties critically depend on the degree of ordering of the chains in the solid state as well as on the density of chemical or structural defects. In general, goodelectronic performance requires strong electronic coupling between adjace nt molecules in the solid-state that yield strong intermolecular π-overlap. Herein, we newly designed and synthesized organic semiconducting materials having both aryl (Ar) and perfluoroaryl (FAr) as substituents for organic electronics along with molecular packing control. Regarding this molecular design, we hypothesized and expected that the Ar and FAr substituents would induce well-defined π-π stacking structure of charge transport units for high performance organic electronics devices.

This is a detailed development for the $A_n$ case, of our previous article entitled "W-Geometries" to be published in Phys. Lett. It is shown that the $A_n$--W-geometry corresponds to chiral surfaces in $CP^n$. This is comes out by discussing 1) the extrinsic geometries of chiral surfaces (Frenet-Serret and Gauss-Codazzi equations) 2) the KP coordinates (W-parametrizations) of the target-manifold, and their fermionic (tau-function) description, 3) the intrinsic geometries of the associated chiral surfaces in the Grassmannians, and the associated higher instanton- numbers of W-surfaces. For regular points, the Frenet-Serret equations for $CP^n$--W-surfaces are shown to give the geometrical meaning of the $A_n$-Toda Lax pair, and of the conformally-reduced WZNW models, and Drinfeld-Sokolov equations. KP coordinates are used to show that W-transformations may be extended as particular diffeomorphisms of the target-space. This leads to higher-dimensional generalizations of the WZNW and DS equations. These are related with the Zakharov- Shabat equations. For singular points, global Pl\"ucker formulae are derived by combining the $A_n$-Toda equations with the Gauss-Bonnet theorem written for each of the associated surfaces., Comment: (60 pages )

The long-term prognosis of expanding bag dilatation therapy using a Matsuo pneumatic bag dilator was evaluated in 163 cases of esophageal achalasia treated by this method over the 26-year period from 1964 to 1989. In all these cases, one year or more had passed since therapy. Practically no correlation was found between the efficacy of the therapy and the grade of esophageal dilation prior to therapy, the previous history of symptomatic distress or the number of dilatations performed. The efficacy of expanding bag cardial dilatation was most obvious in the increase of body weight, 59 cases (36.2%) showing an increase of 1-5 kg and 48 cases (29.4%) showing an increase of 6-10 kg. The therapy was rated "highly effective" in 61 cases (37.4%) and "effective" in 60 cases (36.8%), i.e. it was effective in a total of 121 cases (74.2%). It was rated as being "ineffective" in 16 cases (9.8%) including 4.3% of cases in which an operation had been performed. This indicated that surgical operation of esophageal achalasia should be performed in those cases in which good long-term results were not obtained even after expanding bag dilatation therapy had been carried out several times.

The influence of vagotomy on bicarbonate secretion in the proximal duodenum was assessed in rats receiving truncal, hepatoduodenal and gastric vagotomy. Two weeks after vagotomy, animals fasted for 24 hr were subjected to laparotomy under urethane anesthesia. A proximal duodenal loop excluding the outlet of the common bile duct was prepared as part of an airtight extracorporeal perfusion circuit. The circuit was filled with a bathing solution at pH 4.5 and which was perfused at a rate of 10 ml/min at a constant temperature of 37 degrees C. The pH and CO2 tension of the bathing solution were determined using microelectrodes, and bicarbonate secretion was calculated from the pH and CO2 tension data by the Henderson-Hasselbalch equation. The bicarbonate secretion at the first portion of the duodenum over a 60-min period was significantly higher in the truncal and hepatoduodenal vagotomy groups than in the control group. However, there was no significant difference between the gastric vagotomy and control groups. Furthermore, no significant difference was noted between the truncal and hepatoduodenal vagotomy groups. Since bicarbonate secretion was increased by hepatoduodenal vagotomy, the hepatoduodenal branch of the vagus nerve appeared to inhibit bicarbonate secretion at the first portion of the duodenum.

Nonsteroidal anti-inflammatory drugs (NSAIDs) cause gastric mucosal injury through multiple pharmacological effects (local and systemic) on mucosal defence. Although many factors contribute to mucosal defence, the most consistent and well studied effect of NSAIDs on the mechanisms of mucosal defence is the inhibition of prostaglandin generation. It is known that normal gastric mucosa has the ability to adapt to repeated administration of NSAIDs despite distinct evidence of mucosal injury after single administration. Nevertheless, the high incidence of mucosal injury in patients who are on long term NSAID therapy should not be overlooked, since gastroduodenal injury by long term use is associated with bleeding or perforation, both of which are serious complications. Among several factors responsible for mucosal defence, the role of epithelial renewal is discussed.

We show that there exists a cut-off version of Nambu-Poisson bracket which defines a finite dimensional Lie 3-algebra. The algebra still satisfies the fundamental identity and thus produces N=8 supersymmetric BLG type equation of motion for multiple M2 branes. By counting the number of the moduli and the degree of freedom, we derive an entropy formula which scales as N^{3/2} as expected for the multiple M2 branes., Comment: LaTeX, 21 pages; v2. added some references

We investigate the Bagger-Lambert-Gustavsson model associated with the Nambu-Poisson algebra as a theory describing a single M5-brane. We argue that the model is a gauge theory associated with the volume-preserving diffeomorphism in the three-dimenisonal internal space. We derive gauge transformations, actions, supersymmetry transformations, and equations of motions in terms of six-dimensional fields. The equations of motions are written in gauge-covariant form, and the equations for tensor fields have manifest self-dual structure. We demonstrate that the double dimensional reduction of the model reproduces the non-commutative U(1) gauge theory on a D4-brane with a small non-commutativity parameter. We establish relations between parameters in the BLG model and those in M-theory. This shows that the model describes an M5-brane in a large C-field background., 33 pages

We present two derivations of the multiple D2 action from the multiple M2-brane model proposed by Bagger-Lambert and Gustavsson. The first one is to start from Lie 3-algebra associated with given (arbitrary) Lie algebra. The Lie 3-algebra metric is not positive definite but the zero-norm generators merely correspond to Lagrange multipliers. Following the work of Mukhi and Papageorgakis, we derive D2-brane action from the model by giving a variable a vacuum expectation value. The second derivation is based on the correspondence between M2 and M5. We compactify one dimension and wind M5 brane along this direction. This leads to a noncommutative D4 action. Multiple D2 action is then obtained by suitably choosing the non-commutative parameter on the two-torus. It also implies a natural interpretation to the extra generator in Lie 3-algebra, namely the winding of M5 world volume around $S^1$ which defines the reduction of M theory to \IIA superstring., Comment: 20 pages, minor modifications, references added

Motivated by the recent proposal of an N=8 supersymmetric action for multiple M2-branes, we study the Lie 3-algebra in detail. In particular, we focus on the fundamental identity and the relation with Nambu-Poisson bracket. Some new algebras not known in the literature are found. Next we consider cubic matrix representations of Lie 3-algebras. We show how to obtain higher dimensional representations by tensor products for a generic 3-algebra. A criterion of reducibility is presented. We also discuss the application of Lie 3-algebra to the membrane physics, including the Basu-Harvey equation and the Bagger-Lambert model., Comment: 28 pages

The present study was designed to observe the effect of 15(R)-15-methyl PGE2 (arbaprostil) on duodenal bicarbonate secretion in male Wistar rats anesthetized with urethane. A proximal duodenal loop (1.5cm) was made and perfused with saline (pH4.5) in an air tight circle system. The pH and Pco2 of the perfusing fluid were measured continuously and the quantity of bicarbonate was calculated according to the Henderson-Hasselbalch equation. Vehicle or arbaprostil was injected intravenously as a bolus injection. The total output of bicarbonate in 30 min was as follows; control: 0.449 +/- 0.093 microEq (mean +/- SE); 1,10 and 100 mu/kg of arbaprostil: 0.752 +/- 0.218, 2.75 +/- 0.430 and 5.958 +/- 0.578 microEq respectively. Arbaprostil (10 and 100 micrograms/kg) increased the total output of bicarbonate significantly (p less than 0.001). The rate of secretion was also increased by arbaprostil.