Retrieving poorly degraded OCR documents

A significant portion of currently available documents exist in the form of images, for instance, as scanned documents. Electronic documents produced by scanning and OCR software contain recognition errors. This paper uses an automatic approach to examine the selection and the effectiveness of searching techniques for possible erroneous terms for query expansion. The proposed method consists of two basic steps. In the first step, confused characters in erroneous words are located and editing operations are applied to create a collection of erroneous error-grams in the basic unit of the model. The second step uses query terms and error-grams to generate additional query terms, identify appropriate matching terms, and determine the degree of relevance of retrieved document images to the user's query, based on a vector space IR model. The proposed approach has been trained on 979 document images to construct about 2,822 error-grams and tested on 100 scanned Web pages, 200 advertisements and manuals, and 700 degraded images. The performance of our method is evaluated experimentally by determining retrieval effectiveness with respect to recall and precision. The results obtained show its effectiveness and indicate an improvement over standard methods such as vectorial systems without expanded query and 3-gram overlapping.     

Diabetic-like retinopathy: early and late intervention therapies in galactose-fed rats

PURPOSE: To determine whether the diabetic-like thickening of retinal capillary basement membrane (RCBM) that develops in the galactose-fed rat model of diabetic ocular complications could be halted or ameliorated after 4 or 8 months of galactosemia by treatment with ARI-509, a potent new aldose reductase inhibitor (ARI), or by withdrawal of the galactose diet. METHODS: Weanling female Sprague-Dawley rats were randomized into eight groups and fed laboratory chow plus 50% starch, control group (CON); 50% D-galactose, galactose-fed group (GAL); 50% D-galactose with ARI-509 at 25 mg/kg or 10 mg/kg body wt per day, high-dose prevention group (HDP) and low-dose prevention group (LDP), respectively; 50% D-galactose for 4 or 8 months and then intervention by addition of ARI-509 (25 mg/kg body wt per day), 4-month intervention group (4IN) and 8-month intervention group (8IN), respectively; or 50% D-galactose for 4 or 8 months and then intervention by withdrawing galactose and replacing it with the 50% starch diet, 4-month galactose withdrawal group (4GW) and 8-month galactose withdrawal group (8GW), respectively. After 4, 8, 16, and 24 months of the experimental diets, the levels of carbohydrates in tissues and the extent of RCBM thickening in capillaries of the outer plexiform layer were determined in all groups. RESULTS: Retinal polyol was reduced by 95% in all ARI-treated groups and by 100% in the 4GW and 8GW groups after withdrawal of the galactose. The mean RCBM thickness increased rapidly in GAL rats, becoming almost two times greater (189 +/- 9.4 nm) than in CON rats (103 +/- 3.4 nm) by 24 months. Treatment with ARI-509 in high and low doses (HDP, LDP) initiated with the introduction of the galactose diet significantly prevented RCBM thickening at all time points (P < 0.05). In contrast, intervention by withdrawing galactose from the diet or by adding the high dose of ARI-509 had no significant effect (P < 0.05) on RCBM thickening until the 24-month time point (4IN, 166 +/- 10.3 nm; 8IN, 161 +/- 8.2 nm; 4GW, 136 +/- 5.1 nm; 8GW, 163 +/- 9.6 nm). CONCLUSIONS: Both early and late interventions decreased RCBM thickening compared with that in untreated GAL rats. The decreased thickening, however, was not evident until 16 to 20 months after the intervention. Because RCBM thickening is one of the earliest changes in diabetic and galactosemic retinopathy, the findings suggest that RCBM thickening and possibly subsequent retinal lesions are caused by early biochemical alterations induced by the galactose diet that are not readily reversed. The delayed response to therapy is consistent with that observed in the Diabetes Control and Complications Trial. The cumulative evidence indicates that intervention should begin as early after onset of diabetes as possible, and long follow-up periods should be used to evaluate efficacy.     

A preventive registry for hereditary nonpolyposis colorectal cancer

Hereditary nonpolyposis colorectal cancer (HNPCC) is a genetic disorder characterized by a strong family history of colorectal and extracolonic cancers, usually at a young age. This article presents a new provincial service for families with HNPCC. The Steve Atanas Stavro Familial Gastrointestinal Cancer Registry at Mount Sinai Hospital is accruing patients that meet a set of criteria establishing a putative diagnosis of HNPCC. The objectives of the Registry are to develop and assess patient pedigrees, to coordinate screening procedures for at-risk persons, to maintain a prospective database of patient information, to provide education and support for families and to contribute to research. To date, surgeons and patients are the most common referral sources, while oncologists and geneticists are the least common. The ultimate goal of the HNPCC service is the secondary prevention of cancer and a corresponding decrease in mortality for HNPCC family members.     

The probability of unique solutions of sequencing by hybridization

This paper examines issues related to oral hygiene performance. Results from interviews with 113 adults who had received oral hygiene instruction in eight general dental practices are presented with an emphasis on three issues--the respondents' tooth cleaning pattern (the location within other routines of tooth cleaning), the respondents' tooth cleaning structure (the range of items used in tooth cleaning) and the reported content of the oral hygiene instruction given. Respondents reported that the oral hygiene instruction concentrated upon issues of tooth cleaning structure and did not consider issues of tooth cleaning pattern. The two variables (structure and pattern) were cross-tabulated to create an hypothesis to explain individual variation in tooth cleaning performance. The implications of this hypothesis for understanding patient compliance and developing further quantitative investigations are described.     

Esterified estrogens with and without methyltestosterone decrease arterial LDL metabolism in cynomolgus monkeys

OBJECTIVES: To assess retinal complications and to identify risk factors for retinal complications following aqueous shunt procedures. MATERIALS AND METHODS: Records of 38 consecutive aqueous shunt procedures that were performed on 36 patients at the Eye Institute of the Medical College of Wisconsin, Milwaukee, from June 1993 to March 1995 (minimum follow-up, 6 months) were reviewed. The mean +/- SD follow-up was 11.4 +/- 5.2 months (median, 10.5 months). RESULTS: Twelve patients (32%) had the following retinal complications: 4 serous choroidal effusions (10%) that required drainage, 3 suprachoroidal hemorrhages (8%), 2 vitreous hemorrhages (5%), 1 rhegmatogenous retinal detachment (3%), 1 endophthalmitis (3%), and 1 scleral buckling extrusion (3%). Surgical procedures for retinal complications were required in 8 (67%) of these 12 patients. Visual acuity decreased 2 lines or more in 9 (75%) of these 12 patients. The median onset of a postoperative retinal complication was 12.5 days, with 10 patients (83%) experiencing complications within 35 days. Serous choroidal effusions developed in 10 other patients (26%), and these effusions resolved spontaneously. Visual acuity decreased 2 lines or more in 2 (20%) of these additional 10 patients. Patients who experienced serious retinal complications were significantly older, had a higher rate of hypertension, and postoperative ocular hypotony. Serious retinal complications were distributed evenly among patients with Krupin valves with discs and Molteno and Baerveldt devices. Experience with the Ahmed glaucoma valve implant was limited. CONCLUSION: Aqueous shunt procedures may be associated with significant retinal complications and subsequent visual loss.     

CVT-313, a specific and potent inhibitor of CDK2 that prevents neointimal proliferation

The activity of cyclin-dependent kinase 2 (CDK2) is essential for progression of cells from G1 to the S phase of the mammalian cell cycle. CVT-313 is a potent CDK2 inhibitor, which was identified from a purine analog library with an IC50 of 0.5 microM in vitro. Inhibition was competitive with respect to ATP (Ki = 95 nM), and selective CVT-313 had no effect on other, nonrelated ATP-dependent serine/threonine kinases. When added to CDK1 or CDK4, a 8.5- and 430-fold higher concentration of CVT-313 was required for half-maximal inhibition of the enzyme activity. In cells exposed to CVT-313, hyperphosphorylation of the retinoblastoma gene product was inhibited, and progression through the cell cycle was arrested at the G1/S boundary. The growth of mouse, rat, and human cells in culture was also inhibited by CVT-313 with the IC50 for growth arrest ranging from 1.25 to 20 microM. To evaluate the effects of CVT-313 in vivo, we tested this agent in a rat carotid artery model of restenosis. A brief intraluminal exposure of CVT-313 to a denuded rat carotid artery resulted in more than 80% inhibition of neointima formation. These observations suggest that CVT-313 is a promising candidate for evaluation in other disease models related to aberrant cell proliferation.     

The effects of silver nitrate on the structure and properties of polyurethanes containing pyridyl units

In this study, 2,6-pyridinedimethanol was used as a chain extender to synthesize a new polyurethane, PDM-PU. Further, various amounts of silver nitrate were incorporated to produce PDM-PU/AgNO₃ complexes. FT-IR and UV–Vis analyses confirm the formation of complex in the PDM-PU/AgNO₃. DSC and DMA results show that the glass transition temperature (T _g), dynamic T _g and storage modulus at 25 °C of the PDM-PU/AgNO₃ complexes increase with increasing AgNO₃ content. This is due to the formation of complex structure that can restrict the segmental motion of polymer chains. The TGA and stress–strain test results show that the thermal decomposition temperature, tensile strength and elongation at break increase with the AgNO₃ content initially. Then, they decrease inversely. This indicates that the formation of complex structure raises these properties when the AgNO₃ content is below certain value. But as more coordinate bonds were formed, the specimens become brittle. In addition, the crosslink effect caused by coordinate bonds inhibits the dissolution of polymer chains and thereby reduces the swelling degree of the complexes in solvent. Furthermore, AgNO₃ imparts antibacterial activity against S. aureus and K. pneumoniae to the complexes     

Hierarchical models for analysis and recognition of handwritten characters

Different hierarchical models in pattern analysis and recognition are proposed, based on occurrence probability of patterns. As an important application of recognizing handprinted characters, three typical kinds of hierarchical models such asM _89-89,M _89-36 andM _36-36 have been presented, accompanied by the computer algorithms for computing recognition rates of pattern parts. Moreover, a comparative study of their recognition rates has been conducted theoretically; and numerical experiments have been carried out to verify the analytical conclusions made. Various hierarchical models deliberated in this paper can provide users more or better choices of pattern models in practical application, and lead to a uniform computational scheme (or code). The recognition rates of parts can be improved remarkably by a suitable hierarchical model. For the modelM _89-36 in which case some of the Canadian standard handprinted characters have multiple occurrence probabilities, the total mean recognition rates of the given sample may reach 120% of that by the model proposed by Li et al., and 156% of that obtained from the subjective experiments reported by Suen.