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We present all nontrivial real equiangular tight frames {fm}M m=1 in RN obtained as spherical embeddings of primitive rank 3 graphs on M vertices, and those such that one of their associated M strongly regular graphs on M - 1 vertices is a primitive rank 3 graph. [ABSTRACT FROM AUTHOR]

Importance sampling techniques significantly reduce variance in physically based rendering. In this article, we propose a novel online framework to learn the spatial-varying distribution of the full product of the rendering equation, with a single small neural network using stochastic ray samples. The learned distributions can be used to efficiently sample the full product of incident light. To accomplish this, we introduce a novel closed-form density model, called the Normalized Anisotropic Spherical Gaussian mixture, that can model a complex light field with a small number of parameters and that can be directly sampled. Our framework progressively renders and learns the distribution, without requiring any warm-up phases. With the compact and expressive representation of our density model, our framework can be implemented entirely on the GPU, allowing it to produce high-quality images with limited computational resources. The results show that our framework outperforms existing neural path guiding approaches and achieves comparable or even better performance than state-of-the-art online statistical path guiding techniques. [ABSTRACT FROM AUTHOR]

This study investigated the efficacy and safety profiles of neoadjuvant chemoradiotherapy (NCRT) followed by radical cystectomy (RC) in patients with muscle-invasive bladder cancer (MIBC). Of the 119 patients, 111 underwent RC; ypT0 and downstaging to ≤ypT1 were observed in 42 and 76 patients, respectively. This is the largest series of patients with MIBC undergoing NCRT followed by RC. Introduction: Cisplatin-based systemic chemotherapy is recommended as neoadjuvant treatment for muscle-invasive bladder cancer (MIBC) before radical cystectomy (RC). However, clinical challenges include the possibility of primary chemoresistance and limited feasibility in patients with renal impairment. This study investigated the efficacy and safety profiles of neoadjuvant chemoradiotherapy (NCRT) followed by RC. Materials and Methods: We retrospectively analyzed 119 patients with nonmetastatic MIBC, who were pathologically diagnosed with urothelial carcinoma and underwent NCRT before RC. The pathological response to NCRT was evaluated using RC specimens. Recurrencefree survival (RFS) and cancer-specific survival (CSS) were compared according to pathological responses to NCRT. Results: Of the 119 patients, 111 (93%) underwent RC; ypT0 and downstaging to ≤ypT1 were observed in 42 (38%) and 76 (68%) patients, respectively. In the multivariable analysis, smaller tumor size was independently associated with ypT0. During a median follow-up of 5.2 years, 28 (25%) patients developed recurrence and 22 (20%) died of bladder cancer after RC. The 5-year RFS and CSS rates were 75% and 80%, respectively. The 5-year RFS rates in patients with ypT0, ypTa/is/1, and ≥ypT2 were 87%, 87%, and 46%, respectively. Similarly, patients with ypT0 and ypTa/is/1 had more favorable CSS (90% and 87% at 5 years, respectively) than those with ≥ypT2 (60%, P = .001). None of the patients experienced ≥grade 4 adverse events related to NCRT or ≥grade 4 complications of RC. Conclusions: This study demonstrated sufficient efficacy and safety profile of NCRT followed by RC. Chemoradiotherapy may be a helpful alternative for neoadjuvant treatment before RC. [ABSTRACT FROM AUTHOR]

Objective: To cross-sectionally assess erectile and ejaculatory functions after tetramodal bladder-sparing therapy consisting of transurethral resection, chemoradiotherapy, and consolidative partial cystectomy in patients with muscle invasive bladder cancer. Materials and Methods: Among 72 enrolled male patients who underwent tetramodal bladder-sparing therapy from 2006 to 2019, 42 who visited the outpatient clinic from February to October 2020 received questionnaires. Erectile function, ejaculatory function, and quality of life were assessed using the International Index of Erectile Function short form, the Male Sexual Health Questionnaire Ejaculatory Dysfunction short form, and the Functional Assessment of Cancer Therapy. Results: Among the 42 patients, 9 were excluded because of incomplete responses and 33 were eligible for analyses. The median (range) age at survey and the time from treatment completion to responding to the questionnaires was 70 (50-87) years and 4.2 (0.4-14.0) years, respectively. The median International Index of Erectile Function short form-5 score was 11 (5-25), and 3 (9.1%) and 9 (27.3%) patients had no and mild erectile dysfunction, respectively. The Male Sexual Health Questionnaire Ejaculatory Dysfunction short form results showed that 23 (69.7%) patients responded that they could ejaculate. Patients with higher Male Sexual Health Questionnaire Ejaculatory Dysfunction short form scores had better erectile function and quality of life than those with lower Male Sexual Health Questionnaire Ejaculatory Dysfunction short form scores. Conclusion: Preservation of erectile and ejaculatory functions was demonstrated in muscle invasive bladder cancer patients treated with tetramodal bladder-sparing therapy. In addition to lower urinary tract function, preservation of male sexual function, especially ejaculatory function, in bladder-sparing therapy can be an advantage over radical cystectomy. [ABSTRACT FROM AUTHOR]

Background: Several markers of inflammation have been associated with oncologic outcomes. Prognostic markers are not well-defined for renal cell carcinoma (RCC). We sought to investigate the association of preoperative neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR), and De Ritis ratio with mortality in RCC. Methods: Multi-center retrospective analysis of patients undergoing surgery for RCC. Primary outcome of interest was all-cause mortality (ACM). Secondary outcomes were non-cancer mortality (NCM) and cancer-specific mortality (CSM). Elevated NLR was defined as ≥2.27, elevated PLR as ≥165, and elevated De Ritis ratio as ≥ 2.72. Multivariable cox regression analysis (MVA) was conducted to elucidate risk factors for primary and secondary outcomes, and Kaplan-Meier analysis (KMA) was used to evaluate survival outcomes comparing elevated and non-elevated NLR, PLR, and De Ritis ratio. Results: 2656 patients were analyzed (874 patients had elevated NLR; 480 patients had elevated PLR and 932 patients had elevated De Ritis). Elevated NLR was a significant predictor of ACM (HR 1.32, 95% CI: 1.07-1.64, p=0.003) and NCM (HR 1.79, 95% CI: 1.30-2.46, p<0.001) in MVA. Elevated De Ritis was a significant predictor of ACM (HR 2.04, 95% CI: 1.65-2.52), NCM (HR 1.84, 95% CI: 1.33-2.55, p<0.001), and CSM (HR 1.97, 95% CI:1.48-2.63, p<0.001). KMA revealed significant difference in 5-year overall survival (OS) (48% vs. 68%, p<0.001), non-cancer survival (NCS) (69% vs. 87%, p<0.001), and cancer-specific survival (CSS) (60% vs. 73%, p<0.001) for elevated versus non-elevated NLR. For PLR, there was a difference in 5-year OS (51% vs. 61%, p<0.001) and CSS (60% vs. 73%, p<0.001) with KMA. Conclusions: Elevated NLR was independently associated with worse ACM and NCM, while elevated De Ritis was predictive for CSM in addition to ACM and NCM. These differences may be useful in refining risk stratification with respect to cancer-related and non-cancer mortality in RCC patients and deserve further investigation. [ABSTRACT FROM AUTHOR]

The prognostic value of C-reactive protein was evaluated in patients with non-metastatic papillary renal cell carcinoma undergoing curative surgery using the international multi-institutional cohort. We demonstrated that C-reactive protein was significantly associated with poor recurrence-free survival. C-reactive protein can serve as a useful adjunct biomarker to screen patients with a high risk of recurrence. Introduction: C-reactive protein is a useful biomarker for screening renal cell carcinoma (RCC); however, its significance in papillary RCC is unclear. We assessed the prognostic effect of serum C-reactive protein levels in patients with surgically treated non-metastatic papillary RCC. Patients and Methods: We established an international multiinstitutional database (the INternational Marker Consortium for Renal Cancer) of 3799 patients with surgically treated RCC. Among these, data of 400 patients with non-metastatic papillary RCC were analyzed. An elevated pretreatment serum C-reactive protein level was defined as > 10 mg/L. Associations of clinical covariates with recurrence-free survival were investigated. Results: Among the patients, 174 were Afr ican Amer icans, 155 were European-Americans, 50 were Asians, and 21 were of other races. Pathological T stages were 1, 2, 3, and 4 in 313, 46, 32, and 3 patients, respectively. The median pretreatment C-reactive protein level was 1.0 mg/L; 48 patients exhibited an elevated C-reactive protein level. During follow-up (median 18 months), 30 patients presented recurrence. The 1-, 3-, and 5-year recurrence-free rates were 95%, 91%, and 87%, respectively. Multivariate analysis revealed a significant association of the elevated pretreatment C-reactive protein level with poor recurrence-free survival (hazard ratio 2.47, 95% confidence interval 1.03-5.48; P = .043). The 5-year recurrence-free survival was significantly worse for patients with elevated C-reactive protein levels (67% vs. 90%; P = .001). Conclusions: C-reactive protein is a significant prognostic factor for patients with non-metastatic papillary RCC and can serve as a useful adjunct biomarker for screening patients with a high risk of recurrence. [ABSTRACT FROM AUTHOR]

Nucleation is an activated process in which the system has to overcome a free energy barrier in order for a first-order phase transition between the metastable and the stable phases to take place. In the liquid-to-solid transition, the process occurs between phases of different symmetry, and it is thus inherently a multi-dimensional process, in which all symmetries are broken at the transition. In this Focus Article, we consider some recent studies which highlight the multidimensional nature of the nucleation process. Even for a single-component system, the formation of solid crystals from the metastable melt involves fluctuations of two (or more) order parameters, often associated with the decoupling of positional and orientational symmetry breaking. In other words, we need at least two order parameters to describe the free-energy of a system including its liquid and crystalline states. This decoupling occurs naturally for asymmetric particles or directional interactions, focusing here on the case of water, but we will show that it also affects spherically symmetric interacting particles, such as the hard-sphere system. We will show how the treatment of nucleation as a multi-dimensional process has shed new light on the process of polymorph selection, on the effect of external fields on the nucleation process and on glass-forming ability. [ABSTRACT FROM AUTHOR]

Background and Objectives: Naldemedine is a peripherally acting µ-opioid receptor antagonist that improves opioid-induced constipation. Although clinical trials have excluded patients with poor performance status (PS) and those started on naldemedine early after opioid initiation, clinical practice has used naldemedine for the same patients. Therefore, we investigated the treatment patterns of naldemedine in a real-world setting. Materials and Methods: This was a multicenter, retrospective chart review study of opioid-treated patients with cancer receiving naldemedine. Adverse events that occurred within 7 days of naldemedine initiation were evaluated in those who received one or more doses of the same. Effectiveness was assessed in patients who used naldemedine for more than 7 days. Results: A total of 296 patients satisfied the eligibility criteria, among whom 129 (43.6%) had a PS of ≥3 and 176 (59.5%) started naldemedine within 2 weeks of opioid initiation. Moreover, 203 (79.6%) patients had ≥3 bowel movements per week. Incidences of all grades of diarrhea and abdominal pain were 87 (29.4%) and 12 (4.1%), respectively. No patient had grade 4 or higher adverse events. Conclusions: Although nearly half of the patients receiving naldemedine in clinical practice belonged to populations that were not included in the clinical trials, our results suggested that naldemedine in clinical practice had the same efficacy and safety as that in clinical trials. [ABSTRACT FROM AUTHOR]

An association between the development of overall or specific immune-related adverse events (irAEs) and outcomes of immune checkpoint inhibitors has recently been suggested. To address this emerging association in patients with urothelial cancer receiving pembrolizumab, we conducted a multicenter retrospective analysis, which is the first and largest in an Asian cohort as well as a systematic literature review. We retrospectively evaluated 97 patients with advanced urothelial cancer treated with pembrolizumab as second- or later-line treatment between January 2018 and March 2019. irAEs were categorized by the involved organs and graded using Common Terminology Criteria for Adverse Events version 5.0. Associations between irAEs and pembrolizumab efficacy, including objective response rate (ORR), progression-free survival (PFS), and overall survival (OS), were evaluated. In our review of the literature, 28 studies, including 9 studies involving patients with urothelial cancer and 19 studies reporting the association between outcomes and spectrum of irAEs, were analyzed. Patients with irAEs had significantly higher ORR (52% vs. 16%, P < .01), longer PFS (11.0 months vs. 3.6 months, P < .01) and OS (median not reached vs. 13.1 months, P = .12) than in patients without irAEs. Endocrine (P = .02), pneumological (P = .06), and other (gastrointestinal, hematological, hepatic) (P = .04) irAEs were associated with increased ORR, whereas skin irAEs were not. Endocrine irAEs (P = .04) was associated with improved OS, whereas pneumological and skin irAEs were not. The association between the occurrence of irAEs and clinical efficacy of immune checkpoint inhibitors was consistently supported by the multiple studies we reviewed. The association between clinical outcomes and the spectrum of organs/systems affected by irAEs seems to be inconsistent and could be dependent on tumor type. irAEs were associated with a higher ORR and better survival of patients with advanced urothelial cancer treated with pembrolizumab. [ABSTRACT FROM AUTHOR]

The origin of water's anomalies has been a matter of long-standing debate. A two-state model, dating back to Röntgen, relies on the dynamical coexistence of two types of local structures--locally favored tetrahedral structure (LFTS) and disordered normal-liquid structure (DNLS)--in liquid water. Phenomenologically, this model not only explains water's thermodynamic anomalies but also can rationalize the existence of a liquid-liquid critical point (LLCP) if there is a cooperative formation of LFTS. We recently found direct evidence for the coexistence of LFTS and DNLS in the experimental structure factor of liquid water. However, the existence of the LLCP and its impact on water's properties has remained elusive, leaving the origin of water's anomalies unclear. Here we propose a unique strategy to locate the LLCP of liquid water. First, we make a comprehensive analysis of a large set of experimental structural, thermodynamic, and dynamic data based on our hierarchical two-state model. This model predicts that the two thermodynamic and dynamical fluctuation maxima lines should cross at the LLCP if it exists, which we confirm by hundred-microsecond simulations for model waters. Based on recent experimental results of the compressibility and diffusivity measurements in the no man's land, we reveal that the two lines cross around 184 K and 173 MPa for real water, suggesting the presence of the LLCP around there. Nevertheless, we find that the criticality is almost negligible in the experimentally accessible region of liquid water because it is too far from the LLCP. Our findings would provide a clue to settle the long-standing debate. [ABSTRACT FROM AUTHOR]

Liquid-liquid transition (LLT) is an unconventional transition between two liquid states in a single-component system. This phenomenon has recently attracted considerable attention not only because of its counterintuitive nature but also since it is crucial for our fundamental understanding of the liquid state. However, its physical understanding has remained elusive, particularly of the critical dynamics and phase-ordering kinetics. So far, the hydrodynamic degree of freedom, which is the most intrinsic kinetic feature of liquids, has been neglected in its theoretical description. Here we develop a Ginzburg-Landautype kinetic theory of LLT taking it into account, based on a two-order parameter model. We examine slow critical fluctuations of the nonconserved order parameter coupled to the hydrodynamic degree of freedom in equilibrium. We also study the nonequilibrium process of LLT. We show both analytically and numerically that domain growth becomes faster (slower), depending upon the density decrease (increase) upon the transition, as a consequence of hydrodynamic flow induced by the density change. The coupling between nonconserved order parameter and hydrodynamic interaction results in anomalous domain growth in both nucleation-growth-type and spinodaldecomposition- type LLT. Our study highlights the characteristic features of hydrodynamic fluctuations and phase ordering during LLT under complex interplay among conserved and nonconserved order parameters and the hydrodynamic transport intrinsic to the liquid state. [ABSTRACT FROM AUTHOR]

Crystallization is one of the most familiar and fundamental phase transition phenomena. There is a possibility that crystallization may be enhanced by critical-like fluctuations associated with another nearby phase transition if the order parameter of the former is coupled to that of the latter; however, the mechanism of such order parameter coupling and its generality remain elusive due to the lack of experimental studies. Here we report experimental evidence for a nontrivial coupling between crystallization and liquid-liquid transition (LLT) for a molecular liquid, triphenyl phosphite. We find that the crystal nucleation frequency is drastically enhanced by short-time preannealing near but above the spinodal temperature of LLT. By successfully separating the thermodynamic and kinetic factors governing crystal nucleation, we show that this enhancement is induced by the lowering of the crystal-liquid interfacial energy due to the presence of criticallike order parameter fluctuations. This finding may be regarded as a fingerprint of the presence of LLT below the melting point. Thus, it may allow us not only to control the crystal nucleation frequency by LLT but also to unveil LLT hidden behind crystallization. This enhancement of nucleation frequency by critical-like fluctuations of another ordering phenomenon may be general to a variety of combinations of phase transitions. It would provide a way to control a crystal grain structure, which is a crucial control factor of mechanical and thermal properties of crystalline materials. [ABSTRACT FROM AUTHOR]

Glass transition is characterised by drastic dynamical slowing down upon cooling, accompanied by growing spatial heterogeneity. Its rationalisation by subtle changes in the liquid structure has been long debated but remains elusive, due to intrinsic difficulty in detecting the underlying complex structural ordering. Here we report that structural order parameter characterising local packing capability can well describe the glassy dynamics not only macro-scopically but also microscopically, no matter whether it is driven by temperature or density. A Vogel-Fulcher-Tammann (VFT)-like relation is universally identified between the structural relaxation time and the order parameter for supercooled liquids with isotropic interactions. More importantly, we find such an intriguing VFT-like relation to be statistically valid even at a particle level, between spatially coarse-grained structural order and microscopic particle-level dynamics. Such a unified description of glassy dynamics based solely on structural order is expected to contribute to the ultimate understanding of the long-standing glass-transition problem. [ABSTRACT FROM AUTHOR]

Background/Aims: The most prevalent infectious disease, chronic periodontitis which leads to alveolar bone destruction and subsequent tooth loss, develops due to proinflammatory cytokine production induced by periodontopathic bacteria. Chronic obstructive pulmonary disease (COPD), a non-infectious disease, is the third leading cause of death globally. This condition exacerbates frequently, and which is attributable to proinflammatory cytokine production induced by infection by respiratory microorganisms such as Streptococcus pneumoniae. Although a positive association has recently been revealed between chronic periodontitis and COPD, how periodontitis contributes to the pathogenesis of COPD remains unclear. Therefore, we hypothesized that some periodontopathic bacteria are involved in the exacerbation of COPD through the induction of proinflammatory cytokine production by respiratory epithelial cells. In this connection, COPD develops in the airways; however, because most periodontopathic bacteria are anaerobic, they are unlikely to exhibit stable virulence in the lower respiratory organs in humans. Hence, we aimed to elucidate whether exposure to heat-inactivated periodontopathic bacteria induces proinflammatory cytokine production by several human respiratory epithelial cell lines and in the lower respiratory organs and serum in mice. Methods: Real-time polymerase chain reaction and enzyme-linked immunosorbent assay (ELISA) were used to investigate in vitro induction by heat-inactivated periodontopathic bacteria and S. pneumoniae for mRNA expression and protein production of interleukin (IL)-8 and IL-6 by human respiratory epithelial cell lines. ELISA was also used to determine in vivo induction of cytokine production in the lower respiratory organs and serum of intratracheally heat-inactivated Fusobacterium nucleatum-inoculated mice. Results: Some, but not all, periodontopathic bacteria, especially F. nucleatum, strongly induced IL-8 and IL-6 production by BEAS-2B bronchial epithelial cells. In addition, F. nucleatum induced IL-8 production by A549 alveolar epithelial cells as well as IL-8 and IL-6 production by Detroit 562 pharyngeal epithelial cells. Furthermore, F. nucleatum induced considerably higher cytokine production than S. pneumoniae. This was also observed in the entire lower respiratory organs and serum in mice. Conclusion: Exposure to increased number of F. nucleatum potentially induces proinflammatory cytokine production by human bronchial and pharyngeal epithelial cells, which may trigger exacerbation of COPD. [ABSTRACT FROM AUTHOR]

Liquid-liquid transition (LLT) is the transformation of one liquid to another via first-order phase transition. For example, LLT in a molecular liquid, triphenyl phosphite, is macroscopically the transformation from liquid I in a supercooled state to liquid II in a glassy state. Reflecting the transformation from the liquid to glassy state, the LLT is accompanied by considerable slowing down of overall molecular dynamics, but little is known about how this proceeds at a molecular level coupled with the evolution of the order parameter. We report such information by performing time-resolved simultaneous measurements of dielectric spectroscopy and phase contrast microscopy/Raman spectroscopy by using a dielectric cell with transparent electrodes. We find that the temporal change in molecular mobility crucially depends on whether LLT is nucleation growth type occurring in the metastable state or SD type occurring in the unstable state. Furthermore, our results suggest that the molecular mobility is controlled by the local order parameter: more specifically, the local activation energy of molecular rotation is controlled by the local fraction of locally favored structures formed in the liquid. Our study sheds light on the temporal change in the molecular dynamics during LLT and its link to the order parameter evolution. [ABSTRACT FROM AUTHOR]

Ferroelectricity and antiferroelectricity are widely seen in various types of condensed matter and are of technological significance not only due to their electrical switchability but also due to intriguing cross-coupling effects such as electro-mechanical and electro-caloric effects. The control of the two types of dipolar order has practically been made by changing the ionic radius of a constituent atom or externally applying strain for inorganic crystals and by changing the shape of a molecule for organic crystals. However, the basic physical principle behind such controllability involving crystal-lattice organization is still unknown. On the basis of a physical picture that a competition of dipolar order with another type of order is essential to understand this phenomenon, here we develop a simple model system composed of spheroid-like particles with a permanent dipole, which may capture an essence of this important structural transition in organic systems. In this model, we reveal that energetic frustration between the two types of anisotropic interactions, dipolar and steric interactions, is a key to control not only the phase transition but also the coupling between polarization and strain. Our finding provides a fundamental physical principle for selforganization to a crystal with desired dipolar order and realization of large electro-mechanical effects. [ABSTRACT FROM AUTHOR]

Liquids can be broadly classified into two categories, fragile and strong ones, depending on how their dynamical properties change with temperature. The dynamics of a strong liquid obey the Arrhenius law, whereas the fragile one displays a super-Arrhenius law, with a much steeper slowing down upon cooling. Recently, however, it was discovered that many materials such as water, oxides, and metals do not obey this simple classification, apparently exhibiting a fragile-to-strong transition far above Tg. Such a transition is particularly well known for water, and it is now regarded as one of water's most important anomalies. This phenomenon has been attributed to either an unusual glass transition behavior or the crossing of a Widom line emanating from a liquid-liquid critical point. Here by computer simulations of two popular water models and through analyses of experimental data, we show that the emergent fragile-to-strong transition is actually a crossover between two Arrhenius regimes with different activation energies, which can be naturally explained by a two-state description of the dynamics. Our finding provides insight into the fragile-to-strong transition observed in a wide class of materials. [ABSTRACT FROM AUTHOR]

Tetrahedral interactions describe the behavior of the most abundant and technologically important materials on Earth, such as water, silicon, carbon, germanium, and countless others. Despite their differences, these materials share unique common physical behaviors, such as liquid anomalies, opencrystalline structures, and extremely poor glass-forming ability at ambient pressure. To reveal the physical origin of these anomalies and their link to the shape of the phase diagram, we systematically study the properties of the Stillinger-Weber potential as a function of the strength of the tetrahedral interactionλ.We uncover a unique transition to a reentrant spinodal line at low values of λ, accompanied with a change in the dynamical behavior, from non-Arrhenius to Arrhenius. We then show that a two-state model can provide a comprehensive understanding on how the thermodynamic and dynamic anomalies of this important class of materials depend on the strength of the tetrahedral interaction. Our work establishes a deep link between the shape of the phase diagram and the thermodynamic and dynamic properties through local structural ordering in liquids and hints at why water is so special among all substances. [ABSTRACT FROM AUTHOR]

Water and silica are the most important materials with local tetrahedral symmetry. They have similar crystalline polymorphs and exhibit anomalous density maximum in the liquid state. However, water and silica also show very different characteristics. For instance, the density of water varies much more sharply than that of liquid silica near the maximum as temperature changes. More notably, silica is a very good glass-former, but water is an extremely poor one. The physical origins of these similarities and differences still remain elusive, due to the lack of a microscopic understanding of the structural ordering in these two important liquids. Here, by accessing microscopic structural information by computer simulations, we reveal that local translational symmetry breaking is responsible for the density anomalies. On the other hand, the difference in the degree of local orientational symmetry breaking between water and silica, which originates from the difference in their bonding nature, causes not only the difference in the sharpness of density anomalies, but also their distinct glass-forming abilities. Our work not only shows the crucial roles of local translational and orientational symmetry breaking in the physical properties of the two extremely important materials, water and silica, but also provides a unified scenario applicable for other tetrahedral liquids such as Si, Ge, C, BeF2, and GeO2. [ABSTRACT FROM AUTHOR]

Glass-forming liquids subjected to sufficiently strong shear universally exhibit striking nonlinear behavior; for example, a power-law decrease of the viscosity with increasing shear rate. This phenomenon has attracted considerable attention over the years from both fundamental and applicational viewpoints. However, the out-of-equilibrium and nonlinear nature of sheared fluids have made theoretical understanding of this phenomenon very challenging and thus slower to progress. We find here that the structural relaxation time as a function of the two-body excess entropy, calculated for the extensional axis of the shear flow, collapses onto the corresponding equilibrium curve for a wide range of pair potentials ranging from harsh repulsive to soft and finite. This two-body excess entropy collapse provides a powerful approach to predicting the dynamics of nonequilibrium liquids from their equilibrium counterparts. Furthermore, the two-body excess entropy scaling suggests that sheared dynamics is controlled purely by the liquid structure captured in the form of the two-body excess entropy along the extensional direction, shedding light on the perplexing mechanism behind shear thinning. [ABSTRACT FROM AUTHOR]

The possible role of growing static order in the dynamical slowing down toward the glass transition has recently attracted considerable attention. On the basis of random first-order transition theory, a new method to measure the static correlation length of amorphous order, called "point-to-set" (PTS) length, has been proposed and used to show that the dynamic length grows much faster than the static length. Here, we study the nature of the PTS length, using a polydisperse hard-disk system, which is a model that is known to exhibit a growing hexatic order upon densification. We show that the PTS correlation length is decoupled from the steeper increase of the correlation length of hexatic order and dynamic heterogeneity, while closely mirroring the decay length of two-body density correlations. Our results thus provide a clear example that other forms of order can play an important role in the slowing down of the dynamics, casting a serious doubt on the order-agnostic nature of the PTS length and its relevance to slow dynamics, provided that a polydisperse hard-disk system is a typical glass former. [ABSTRACT FROM AUTHOR]

A liquid-liquid transition (LLT) in a single-component substance is an unconventional phase transition from one liquid to another. LLT has recently attracted considerable attention because of its fundamental importance in our understanding of the liquid state. To access the order parameter governing LLT from a microscopic viewpoint, here we follow the structural evolution during the LLT of an organic molecular liquid, triphenyl phosphite (TPP), by timeresolved small- and wide-angle X-ray scattering measurements. We find that locally favored clusters, whose characteristic size is a few nanometers, are spontaneously formed and their number density monotonically increases during LLT. This strongly suggests that the order parameter of LLT is the number density of locally favored structures and of nonconserved nature. We also show that the locally favored structures are distinct from the crystal structure and these two types of orderings compete with each other. Thus, our study not only experimentally identifies the structural order parameter governing LLT, but also may settle a longstanding debate on the nature of the transition in TPP, i.e., whether the transition is LLT or merely microcrystal formation. [ABSTRACT FROM AUTHOR]

Colloidal clusters are an unusual state of matter where tunable interactions enable a sufficient reduction in their degrees of freedom that their energy landscapes can become tractable - they form a playground for statistical mechanics and promise unprecedented control of structure on the submicron lengthscale. We study colloidal clusters in a system where a short-ranged polymer-induced attraction drives clustering, while a weak, long-ranged electrostatic repulsion prevents extensive aggregation. We compare experimental yields of cluster structures with theory which assumes simple addition of competing isotropic interactions between the colloids. Here we show that for clusters of size 4⩽m ⩽7, the yield of minimum energy clusters is much less than expected. We attribute this to an anisotropic self-organized surface charge distribution which leads to unexpected kinetic trapping. We introduce a model for the coupling between counterions and binding sites on the colloid surface with which we interpret our findings. [ABSTRACT FROM AUTHOR]

The sedimentation of an initially inhomogeneous distribution of hard-sphere colloids confined in a slit is simulated using the multi-particle collision dynamics scheme which takes into account hydrodynamic interactions mediated by the solvent. This system is an example for soft matter driven out of equilibrium where various length and time scales are involved. The initial laterally homogeneous density profiles exhibit a hydrodynamic Rayleigh–Taylor-like instability. Solvent backflow effects lead to an intricate non-linear behaviour which is analyzed via the solvent flow field and the colloidal velocity correlation function. Our simulation data are in good agreement with real-space microscopy experiments. [ABSTRACT FROM AUTHOR]

Abstract   Objectives The aim of the present study was to determine the potential for pancreatic calcification in autoimmune pancreatitis by investigating osteopontin and CD44 expression. Methods Human pancreatic tissues in normal pancreas, chronic pancreatitis, and autoimmune pancreatitis were obtained from the surgical specimens of 42 patients. Pancreatic tissues from male Wistar Bonn/Kobori rats were also used as an animal autoimmune pancreatitis model. Results The incidences of osteopontin expression in centroacinar cells in chronic pancreatitis with calcification and in autoimmune pancreatitis were significantly greater than that in normal pancreas (P P Conclusions These results suggest that autoimmune pancreatitis has the potential for pancreatic calcification over a long-term clinical course. [ABSTRACT FROM AUTHOR]

This report describes a patient with radiation-induced rectal cancer with an unusual history. A 51-year-old man was admitted in 2000 because of ichorrhea of the skin on the left loin. The patient had received irradiation for a suspicious diagnosis of a malignant tumor in the pelvic cavity in 1975. A subcutaneous abscess in the right loin appeared in 1989, and rectocutaneous fistula was noted in 1992. Moreover, radiation-induced rectal cancer developed in 2000. Plain computed tomography and magnetic resonance imaging of the pelvis demonstrated a presacral mass and tumor in the rectum. Finally, we diagnosed the presacral mass to be an abscess attached to the center of the rectal cancer. The rectum was resected by Miles’ operation and a colostomy of the sigmoid colon was also performed. Many cases of radiation-induced rectal cancer have been reported. However, this is a rare case of radiation-induced rectal cancer originating from a presacral abscess and rectocutaneous fistula. [ABSTRACT FROM AUTHOR]

In this paper, we obtain certain discrete orthogonal polynomials expressed in terms of the $(d+1,2(d+1))$-hypergeometric functions, from the eigenmatrices of character algebras. [ABSTRACT FROM AUTHOR]

A temperature sensor integrated on a micro-device for biological experiments requires affordable, rapid and easy thermal calibration. However, such calibration cannot usually be done directly under the microscope, a fact that impedes biological experiments. We present in this paper an inexpensive and rapid method to achieve thermal calibration directly under the microscope. It is based on the use of a thermotropic liquid crystal: the 4-n-octyl-4-cyanobiphenyl (8 CB) exhibiting an isothermal phase change at 313 K that can be monitored optically. We demonstrate the advantages of this method by calibrating the temperature sensor integrated onto a micro-device. [ABSTRACT FROM AUTHOR]

This study theoretically investigates the effects of band structure parameters, such as the bandgap, effective mass, and Brillouin zone (BZ) width, on impact ionization coefficients. A Monte-Carlo simulation considering analytical and tunable band structures reveals that the smaller BZ width significantly reduces impact ionization coefficients, and its impacts can outperform those of the bandgap. The smaller BZ width also leads to positive temperature dependence of impact ionization coefficients, which is discussed focusing on the occurrence of the Bloch oscillation. Our results show the importance of the BZ width in discussing the behavior of impact ionization coefficients. [ABSTRACT FROM AUTHOR]

We formulate scattering mechanisms in quasi-two-dimensional systems with a large density of interface states such as 4H-SiC MOS interfaces, and calculate the electron Hall mobility in 4H-SiC MOS inversion layers by Monte Carlo simulation. In addition to phonon, ionized impurity, and surface roughness scattering, we take account of Coulomb scattering by the electrons trapped at the interface states and the interface fixed charges and scattering by electrically neutral defects. Considering that the number of trapped electrons can be comparable to or larger than that of mobile electrons, the trapped electrons are assumed to contribute to screening as well as scattering. Using the developed model, we analyze the dependence of Hall mobility in 4H-SiC MOS inversion layers on the body acceptor density, temperature, and interface state density. Our calculation reasonably reproduces the experimental behaviors of Hall mobility. We also discuss the physical mechanisms underlying the obtained results. [ABSTRACT FROM AUTHOR]

Electric-field dependence of optical absorption induced by Franz–Keldysh (FK) effect strongly depends on the value of the reduced effective mass along electric field. In this study, reverse current–voltage characteristics of 4H-SiC{110} p–n junction diodes under sub-bandgap illumination were investigated. Under a reverse bias condition, a photocurrent induced by FK effect was observed and increased with the reverse voltage. We calculated a photocurrent with consideration of phonon-assisted optical absorption induced by FK effect in a depletion region using the reduced effective mass perpendicular to the c-axis ( = 0.26 ), and the calculated values showed good agreement with the experimental values. This result indicates that the anisotropy of optical absorption induced by FK effect in 4H-SiC is small, since the reduced effective mass perpendicular to the c-axis ( = 0.26 ) is close to that parallel to the c-axis ( = 0.28 ). [ABSTRACT FROM AUTHOR]

A system far from equilibrium is characterized by unconventional many-body dynamical effects, which can lead to anomalous density fluctuations and mass transport. Interestingly, these structural and dynamic features often emerge simultaneously in driven dissipative systems. Here we seek an origin of their co-existence by numerical simulations of a two-dimensional, driven system of inelastic particles without external damping terms. We reveal a causal link between superdiffusive transport and giant density fluctuations. The kinetic dissipation upon particle collisions depends on the relative velocity of colliding particles, and is responsible for the self-generated large-scale persistent directional motion of particles that underlies the link between structure and transport. This scenario is supported by a simple scaling argument. [ABSTRACT FROM AUTHOR]

Electrophoresis is one of the most important methods for separating colloidal particles, carbohydrates, pharmaceuticals, and biological molecules such as DNA, RNA, proteins, in terms of their charge (or size). This method relies on the correlation between the particle drift velocity and the charge (or size). For a high-resolution separation, we need to minimize fluctuations of the drift velocity of particles or molecules. For a high throughput, on the other hand, we need a concentrated solution, in which many-body electrostatic and hydrodynamic interactions may increase velocity fluctuations. Thus, it is crucial to reveal what physical factors destabilize the coherent electrophoretic motion of charged particles. However, this is not an easy task due to complex dynamic couplings between particle motion, hydrodynamic flow, and motion of ion clouds. Here we study this fundamental problem using numerical simulations. We reveal that addition of salt screens both electrostatic and hydrodynamic interactions, but in a different manner. This allows us to minimize the fluctuations of the particle drift velocity for a particular salt concentration. This may have an impact not only on the basic physical understanding of dynamics of driven charged colloids, but also on the optimization of electrophoretic separation. [ABSTRACT FROM AUTHOR]

Phase separation is a key phenomenon producing a heterogeneous structure in various kinds of material covering from liquid to soft and to hard matter. It is known that viscoelastic effects play a crucial role in phase separation of dynamically asymmetric mixtures such as polymer solutions, protein solutions, and colloidal suspensions, under a sufficiently deep quench: viscoelastic phase separation. In contrast to the common knowledge of normal phase separation that the minority phase always form isolated droplets, viscoelastic phase separation can produce a percolated network structure of a minority phase. Because of unique mechanical and electric properties of the network structure, viscoelastic phase separation is important not only scientifically, but also technologically. Here we report experimental evidence that viscoelastic phase separation of polymer solution accompanies transient gelation as a dynamic crossover, on the way to the final coexistence of the polymer-rich and -poor liquid phases. We find that dynamic phase diagrams can be scaled by the degree of polymerization N into the master one, suggesting the universality of transient gelation, i.e., dynamic crossover, in polymer solutions. This allows us to predict the type of phase separation as a function of the temperature, the polymer concentration and N of the mixture. [ABSTRACT FROM AUTHOR]

Colloidal suspensions can be regarded as an ideal model system for such key daily materials as emulsions, protein solutions, foods, and inks. When colloidal particles strongly attract each other, they aggregate, phase-separate, and sometimes form gels. The basic understanding of this spatially heterogeneous jamming process is of crucial importance from both scientific and industrial viewpoints. Usually it is believed that if colloids attract very strongly with adhesion energy more than 10 times the thermal energy, networks formed by aggregation do not coarsen with time and a stable gel is immediately formed. Contrary to this common belief, we demonstrate by numerical simulation that the coarsening of a colloidal network can proceed by self-generated mechanical stress even without any thermal noise for a system of long-range interactions: fracture-induced coarsening. This remarkable kinetic pathway of purely mechanical origin may shed new light on our basic understanding of the stability and aging (or coarsening) behaviour of colloidal gels. [ABSTRACT FROM AUTHOR]