Defining Dry Eye from a Clinical Perspective

Over the past decades, the number of patients with dry eye disease (DED) has increased dramatically. The incidence of DED is higher in Asia than in Europe and North America, suggesting the involvement of cultural or racial factors in DED etiology. Although many definitions of DED have been used, discrepancies exist between the various definitions of dry eye disease (DED) used across the globe. This article presents a clinical consensus on the definition of DED, as formulated in four meetings with global DED experts. The proposed new definition is as follows: “Dry eye is a multifactorial disease characterized by a persistently unstable and/or deficient tear film (TF) causing discomfort and/or visual impairment, accompanied by variable degrees of ocular surface epitheliopathy, inflammation and neurosensory abnormalities.” The key criteria for the diagnosis of DED are unstable TF, inflammation, ocular discomfort and visual impairment. This definition also recommends the assessment of ocular surface epitheliopathy and neurosensory abnormalities in each patient with suspected DED. It is easily applicable in clinical practice and should help practitioners diagnose DED consistently. This consensus definition of DED should also help to guide research and clinical trials that, to date, have been hampered by the lack of an established surrogate endpoint.     

The relationship between squaraine dye surface morphology and sensitization behavior on SnS2 electrodes

Bis(4-dimethylamino-2-dihydroxyphenyl)squaraine (1-1 OHSQ) dyes were deposited on van der Waals surfaces of SnS₂ single crystals by two methods, dipping in a dye solution and evaporation of dye solution. Dye morphologies and photosensitization properties on the same samples were studied with atomic force microscopy (AFM) and photoelectrochemical measurements. AFM experiments in air revealed two distinct morphologies of dye aggregates and photocurrent measurements on the same samples in aqueous electrolytes showed correspondingly different photocurrent spectra. Three-dimensional needle-shaped 1-1 OHSQ aggregates aligned along crystal directions and showed a broad excitation spectrum that extended into the near-IR region with a peak around 800 nm. In contrast, flat aggregates presumably consisting of monolayers of 1-1 OHSQ molecules, had a sensitization maximum around 680 nm. Both peaks were red-shifted from absorption peak of 1-1 OHSQ in bulk dichloromethane solution. Spectral differences between these dye aggregates are discussed in terms of intermolecular interactions.     

The effects of air pollution and climatic factors on atmospheric corrosion of marble under field exposure

The atmospheric corrosion of marble was evaluated in terms of SO₂ concentration as air pollution and climatic factors such as rainfall, relative humidity, temperature and so on under the field exposure. Marble of calcite type (CaCO₃) was exposed to outdoor atmospheric environment with and without a rain shelter at four test sites in the southern part of Vietnam for 3-month, 1- and 2-year periods from July 2001 to September 2003. The thickness loss of marble was investigated gravimetrically. X-ray diffraction and X-ray fluorescent methods were applied to study corrosion products on marble. The corrosion product of marble was only gypsum (CaSO₄ · 2H₂O) and was washed out by rain under the unsheltered exposure condition. It was found that the most substantial factors influencing the corrosion of marble were rainfall, SO₂ concentration in the air and relative humidity. Based on the results obtained, we estimated the dose-response functions for the atmospheric corrosion of marble in the southern part of Vietnam.     

Suppressive effects of bifidobacteria on lipid peroxidation in the colonic mucosa of iron-overloaded mice

The antioxidative effects of live bifidobacteria on lipid peroxidation in the colonic mucosa were investigated. Bifidobacterium bifidum strain Yakult, which has been used for production of fermented milk, most effectively inhibited lipid peroxidation catalyzed by ferrous iron in liposomes among 10 species of bifidobacteria from human intestinal flora. Oral administration of B. bifidum strain Yakult for 2 wk significantly decreased the level of lipid peroxide (thiobarbituric acid reactive substance) in the colonic mucosa of iron-overload mice (Fe 0.07% in diet). The iron concentrations in plasma and cecum contents were not affected by administration of B. bifidum strain Yakult. Bifidobacterium bifidum strain Yakult had no chelating or incorporating activity for ferrous iron in vitro. Therefore, the antioxidative effect of B. bifidum strain Yakult in the colonic mucosa was not thought to be based on the removal of ferrous iron from the reaction system of lipid peroxidation. These results suggested that B. bifidum strain Yakult protected the colonic mucosa from oxidative injury without inhibiting iron absorption.     

ADAPTIVE CONTROL DESIGN FOR NONLINEARLY PARAMETERIZED SYSTEMS WITH A TRIANGULAR STRUCTURE

A novel adaptive backstepping design for a class of nonlinearly parameterized systems with a triangular structure is proposed. Under the Lipschitz condition with respect to unknown parameters of the system, an effective adaptive controller is designed without the requirement on the compactness of the unknown parametric set. Especially, the proposed adaptive control enables the advantage of “tuning function concept”, which results in only one estimation law for the unknown parameters. Our simulation with induction motor model particularly shows the viability of the obtained results.     

A theory of tie‐set graph and its application to information network management

This paper presents a new circuit theoretical concept based on the principal partition theorem for distributed network management focusing on loops of an information network. To realize a simple network management with the minimum number of local agents, namely the topological degrees of freedom of a graph, a reduced loop agent graph generated by contracting the minimal principal minor is proposed. To investigate the optimal distribution of the loop agents, a theory of tie‐set graph is proposed. Considering the total processing load of loop agents, a complexity of a tie‐set graph is introduced to obtain the simplest tie‐set graph with the minimum complexity. As for the simplest tie‐set graph search, an experimental result shows that the computational time depends heavily on the nullity of the original graph. Therefore, a tie‐set graph with the smallest nullity is essential for network management. Copyright © 2001 John Wiley & Sons, Ltd.     

Formation energies and site preference of substitutional divalent cations in carbonated apatite

First-principles calculations were performed to examine defect formation energies and site preference of substitutional divalent cations M²⁺ (M = Mg, Cu, Zn, Cd, Sr, Pb, and Ba) in hydroxyapatite (HAp, Ca₁₀(PO₄)₆(OH)₂) and carbonated apatite (CAp). All inequivalent substitutional sites of and M²⁺ were investigated to determine their most preferential sites. For all M²⁺ studied, their defect formation energies for the most stable substitutional sites were lower in CAp than in hydroxyapatite (HAp), demonstrating that M²⁺ are preferentially substituted into CAp over HAp. For Ca sites in CAp, correlations between the defect formation energies and Ca-O bond lengths showed that bigger and smaller M²⁺ than Ca²⁺ are preferentially substituted for Ca sites with longer and shorter bond lengths than those in HAp, respectively. In addition, Ca sites with lower coordination numbers than 6 are preferentially substituted by Zn²⁺ and Cu²⁺ that originally tend to form 4- or 5-fold coordination in their phosphate crystals. substitution is therefore likely to effectively stabilize substitutional foreign ions by modifying bond lengths and coordination numbers of Ca sites from those in pure HAp. These effects may play an important role in enhancing the M²⁺ solubility into CAp.     

An autonomous distributed control method based on tie‐set graph theory in future grid

In future power grids where electricity flows bidirectionally, the essential problem is to maximize the total efficiency of distributed energy resources. In complicated and large‐scale systems such as modern power distribution networks, maximizing the efficiency of the entire system as a whole is extremely difficult. To solve the global optimization problem of such a complex network, this paper proposes an efficient distributed control method for future grid on the basis of tie‐set graph theory, where a tie‐set is a set of all the edges in a loop of a graph. On the basis of tie‐set graph theory, global optimization of an entire network can be realized as a result of local optimization in μ‐dimensional liner vector space, where μ is the nullity of the underlying graph of a power network. Although each tie‐set has its limited local information, an entire network is gradually optimized in an orderly manner because of the theoretical basis of a tie‐set graph. Simulation results of several thousand‐node networks demonstrate balanced allocation of dispersed energy resources and thus effectiveness of the proposed method. Copyright © 2012 John Wiley & Sons, Ltd.