Application of higher-order spectra for automated grading of diabetic maculopathy

Diabetic macular edema (DME) is one of the most common causes of visual loss among diabetes mellitus patients. Early detection and successive treatment may improve the visual acuity. DME is mainly graded into non-clinically significant macular edema (NCSME) and clinically significant macular edema according to the location of hard exudates in the macula region. DME can be identified by manual examination of fundus images. It is laborious and resource intensive. Hence, in this work, automated grading of DME is proposed using higher-order spectra (HOS) of Radon transform projections of the fundus images. We have used third-order cumulants and bispectrum magnitude, in this work, as features, and compared their performance. They can capture subtle changes in the fundus image. Spectral regression discriminant analysis (SRDA) reduces feature dimension, and minimum redundancy maximum relevance method is used to rank the significant SRDA components. Ranked features are fed to various supervised classifiers, viz. Naive Bayes, AdaBoost and support vector machine, to discriminate No DME, NCSME and clinically significant macular edema classes. The performance of our system is evaluated using the publicly available MESSIDOR dataset (300 images) and also verified with a local dataset (300 images). Our results show that HOS cumulants and bispectrum magnitude obtained an average accuracy of 95.56 and 94.39 % for MESSIDOR dataset and 95.93 and 93.33 % for local dataset, respectively.

Strength and stiffness assessment technologies for improving grading effectiveness of radiata pine wood.

This work was designed to provide the Australian structural radiata pine processing industry with some indications for improving stress grading methods and/or technologies to give an increase in structural grade yields, and significantly reduce processing costs without compromising product quality. To achieve this, advanced statistical techniques were used in conjunction with state-of-the-art property measurement systems applied to the same sample of sawn timber. Acoustic vibration analyses were conducted on green and dry boards. Raw data from existing in-line systems was captured on the same boards. The Metriguard HCLT stress rating system was used as the "reference" machine grading because of its current common use in the industry. A WoodEye optical scanning system and an X-ray LHG scanner were also able to provide relevant information on knots. The data set was analyzed using classical and advanced statistical tools to provide correlations between data sets, and to develop efficient strength and stiffness prediction equations. Reductions in non-structural dry volumes can be achieved..

Improvement in the voltage grading (axial and radial) of the generator column of a Van de Graaf generator by the use of a resistor chain

It is well known that the use of a series of resistors, connected between the equipotential rings of a Van de Graaff generator, improves the axial voltage grading of the generator. The work reported in this paper shows how the resistor chain also improves the radial voltage gradient. The electrolytic field mapping technique was adopted in the present work.

Peripheral facial palsy : Grading, Etiology, and Melkersson-Rosenthal Syndrome

The objective of this study was to assess the utility of two subjective facial grading systems, to evaluate the etiologic role of human herpesviruses in peripheral facial palsy (FP), and to explore characteristics of Melkersson-Rosenthal syndrome (MRS). Intrarater repeatability and interrater agreement were assessed for Sunnybrook (SFGS) and House-Brackmann facial grading systems (H-B FGS). Eight video-recorded FP patients were graded in two sittings by 26 doctors. Repeatability for SFGS was from good to excellent and agreement between doctors from moderate to excellent by intraclass correlation coefficient and coefficient of repeatability. For H-B FGS, repeatability was from fair to good and agreement from poor to fair by agreement percentage and kappa coefficients. Because SFGS was at least as good in repeatability as H-B FGS and showed more reliable results in agreement between doctors, we encourage the use of SFGS over H-B FGS. Etiologic role of human herpesviruses in peripheral FP was studied by searching DNA of herpes simplex virus (HSV) -1 and -2, varicella-zoster virus (VZV), human herpesvirus (HHV) -6A, -6B, and -7, Epstein-Barr virus (EBV), and cytomegalovirus (CMV) by PCR/microarray methods in cerebrospinal fluid (CSF) of 33 peripheral FP patients and 36 controls. Three patients and five controls had HHV-6 or -7 DNA in CSF. No DNA of HSV-1 or -2, VZV, EBV, or CMV was found. Detecting HHV-7 and dual HHV-6A and -6B DNA in CSF of FP patients is intriguing, but does not allow etiologic conclusions as such. These DNA findings in association with FP and the other diseases that they accompanied require further exploration. MRS is classically defined as a triad of recurrent labial or oro-facial edema, recurrent peripheral FP, and plicated tongue. All three signs are present in the minority of patients. Edema-dominated forms are more common in the literature, while MRS with FP has received little attention. The etiology and true incidence of MRS are unknown. Characteristics of MRS were evaluated at the Departments of Otorhinolaryngology and Dermatology focusing on patients with FP. There were 35 MRS patients, 20 with FP and they were mailed a questionnaire (17 answered) and were clinically examined (14 patients). At the Department of Otorhinolaryngology, every MRS patient had FP and half had the triad form of MRS. Two patients, whose tissue biopsies were taken during an acute edema episode, revealed nonnecrotizing granulomatous findings typical for MRS, the other without persisting edema and with symptoms for less than a year. A peripheral blood DNA was searched for gene mutations leading to UNC-93B protein deficiency predisposing to HSV-1 infections; no gene mutations were found. Edema in most MRS FP patients did not dominate the clinical picture, and no progression of the disease was observed, contrary to existing knowledge. At the Department of Dermatology, two patients had triad MRS and 15 had monosymptomatic granulomatous cheilitis with frequent or persistent edema and typical MRS tissue histology. The clinical picture of MRS varied according to the department where the patient was treated. More studies from otorhinolaryngology departments and on patients with FP would clarify the actual incidence and clinical picture of the syndrome.

Influence of soil grading on the characteristics of cement stabilised soil compacts

The paper deals with experimental investigations aiming at specifying optimum soil grading limits for the production of cement stabilised soil bricks (CSSB). Wide range of soil grading curves encompassing both fine and coarse grained soils were considered. Strength, durability and absorption characteristics of CSSB were examined considering 14 different types of soil grading curves and three cement contents. The investigations show that there is optimum clay content for the soil mix which yields maximum compressive strength for CSSB and the optimum clay content is about 10 and 14 % for fine grained and coarse grained soils respectively. Void ratio of the compacted specimens is the lowest at the optimum clay content and therefore possesses maximum strength at that point. CSSB using fine grained soils shows higher strength and better durability characteristics when compared to the bricks using coarse grained soils.

Finite Element Solutions for Plane Strain Mode I Crack with Strain Grading Effect

In this paper, a new phenomenological theory with strain gradient effects is proposed to account for the size dependence of plastic deformation at micro- and submicro-length scales. The theory fits within the framework of general couple stress theory and three rotational degrees of freedom omega(i) are introduced in addition to the conventional three translational degrees of freedom mu(i). omega(i) is called micro-rotation and is the sum of material rotation plus the particles' relative rotation. While the new theory is used to analyze the crack tip field or the indentation problems, the stretch gradient is considered through a new hardening law. The key features of the theory are that the rotation gradient influences the material character through the interaction between the Cauchy stresses and the couple stresses; the term of stretch gradient is represented as an internal variable to increase the tangent modulus. In fact the present new strain gradient theory is the combination of the strain gradient theory proposed by Chen and Wang (Int. J. Plast., in press) and the hardening law given by Chen and Wang (Acta Mater. 48 (2000a) 3997). In this paper we focus on the finite element method to investigate material fracture for an elastic-power law hardening solid. With remotely imposed classical K fields, the full field solutions are obtained numerically. It is found that the size of the strain gradient dominance zone is characterized by the intrinsic material length l(1). Outside the strain gradient dominance zone, the computed stress field tends to be a classical plasticity field and then K field. The singularity of stresses ahead of the crack tip is higher than that of the classical field and tends to the square root singularity, which has important consequences for crack growth in materials by decohesion at the atomic scale. (C) 2002 Elsevier Science Ltd. All rights reserved.

Use of length-weight relationship in grading processed beche-de-mer

Holothurians, belonging to the species Holothuria scabra, have been collected by diver-fishermen and processed for export. There is an active fishery for these animals in Palk Bay and Gulf of Mannar, off the north-western coast of Sri Lanka. The absence of standardized method of grading has led to unwarranted variation in sale prices and sometimes in loss of foreign exchange in Sri Lanka. In this paper an attempt is made to present a method to grade processed beche-de-mer by using the lenght-weight relationship.

重离子束治疗皮肤恶性肿瘤的初步临床结果；Clinical trial of carbon ion radiotherapy for malignant neoplasm of skin

目的:评价重离子束对皮肤恶性肿瘤放射治疗的近期疗效和毒副反应。方法:29例皮肤恶性肿瘤患者分6批接受重离子束放射治疗,其中恶性黑色素瘤13例,皮肤鳞癌及Bowen’s病各6例,基底细胞癌2例,其他皮肤恶性肿瘤2例。照射总剂量(50～70)GyE/(6～12)d,单次剂量5.5～11.67GyE,1f/d,连续治疗。采用RTOG标准和WHO近期疗效标准分别评价毒副反应和近期疗效。结果:截止2009-05,中位随访时间为13.5个月(1～25个月),随访率为100%。29例患者中完全缓解(CR)24例(82.8%),部分缓解(PR)5例(17.2%),有效率(RR)为100%,中位生存时间为22.8个月(95%CI:20.6～24.9)。皮肤反应0度11例(37.9%),Ⅰ度9例(31.0%),Ⅱ度6例(20.7%),Ⅲ度2例(6.9%),Ⅳ度1例(3.4%);血液毒副反应治疗前后无明显改变。结论:重离子束(12C6+)放射治疗皮肤恶性肿瘤近期疗效好,并发症轻,远期疗效、晚期副反应等尚需进一步长期全面的观察和更多的研究提供依据。

Volumetric consequences of particle loss by grading entropy.

Chemical and biological processes, such as dissolution in gypsiferous sands and biodegradation in waste refuse, result in mass or particle loss, which in turn lead to changes in solid and void phase volumes and grading. Data on phase volume and grading changes have been obtained from oedometric dissolution tests on sand–salt mixtures. Phase volume changes are defined by a (dissolution-induced) void volume change parameter (Λ). Grading changes are interpreted using grading entropy coordinates, which allow a grading curve to be depicted as a single data point and changes in grading as a vector quantity rather than a family of distribution curves. By combining Λ contours with pre- to post-dissolution grading entropy coordinate paths, an innovative interpretation of the volumetric consequences of particle loss is obtained. Paths associated with small soluble particles, the loss of which triggers relatively little settlement but large increase in void ratio, track parallel to the Λ contours. Paths associated with the loss of larger particles, which can destabilise the sand skeleton, tend to track across the Λ contours.

Timber grading seminar - Some things you should know about how strength grading works and what is changing in the standards.

Presentations from the seminar on timber grading. "This grading seminar will give you a crash course in timber strength grading, what it is, how it works, and how it is changing. It aims to demystify timber grading, tackle some widely held misconceptions, and tell you the things you need to be aware of to improve profitability, and remain correct and safe in what you do. The timber resource in the UK is changing, technology is advancing, and standards are being modified. This seminar will bring you the latest position, informed by CEN and BSI standards committee work and research conducted by the SIRT network."

Strength grading of sawn timber in Europe: an explanation for engineers and researchers.

This paper is a concise explanation of the normative background to strength grading in Europe, addressing important aspects that are commonly misunderstood by structural engineers and timber researchers. It also highlights changes that are being made to the standards to: incorporate requirements of the construction products regulations; add improvements to the system to accommodate the latest knowledge and technology; and widen the application of the standards. Where designs need to be optimised, there is an opportunity to use the system more intelligently, in combination with the latest technology, to better fit design values to the true properties of the timber resource. This can bring a design enhancement equivalent to effort improving other aspects of the structure, such as connectors and reinforcement. Parallel to this, researchers working on other aspects of structural improvement need to understand what grades really mean in respect of the properties of the timber, in order to correctly analyse the results of testing. It is also useful to know how techniques used in grading can assist with material properties characterisation for research. The amount of destructive testing involved in establishing machine grading settings and visual grading assignments presents a barrier to greater use of local timber, and diversification of commercial species, so it is important that any researcher assessing the properties of such species should consider, from the outset, doing the research in a way that can contribute to a grading dataset at a later date. This paper provides an overview of what is required for this.

Checklists for grading object-oriented CS1 programs: concepts and misconceptions

Sanders, K. and Thomas, L. 2007. Checklists for grading object-oriented CS1 programs: concepts and misconceptions. In Proceedings of the 12th Annual SIGCSE Conference on innovation and Technology in Computer Science Education (Dundee, Scotland, June 25 - 27, 2007). ITiCSE '07. ACM, New York, NY, 166-170