bluuebunny/crossref_metadata_2025 huggingface dataset:
Total matrix addressing
Authors: Smith Euan C.
Published: January 2008

Abstract— A new passive‐matrix OLED drive technology, Total matrix addressing (TMA™), has been developed, which substantially extends the application space for passive panels beyond the limited panel size and resolution of existing passive‐matrix drive schemes. A number of demonstration systems have been constructed to test the viability and performance of this drive scheme. The development of both the TMA drive methodology and image factorization algorithm will be described, and preliminary performance figures from the demonstration systems presented.
Consecutive multiline addressing: A scheme for addressing PMOLEDs
Authors: Xu Chihao , Karrenbauer Andreas , Soh Kian Min , Codrea Cosmin
Published: January 2008

Abstract— Consecutive multiline addressing (CMLA) has been developed to increase a PMOLED display's lifetime, resolution, and power efficiency. Mathematically, it decomposes an image matrix into a set of multiline matrices and a residual single‐line matrix. The decomposition is lossless and implemented by a combinatorial algorithm allowing small chip size for the logic and high processing speed, e.g., for video applications. The additional memory needed for CMLA is just a fraction of the graphic data memory (GDRAM). The printed‐circuit‐board (PCB) prototype with a field programmable gate array (FPGA) proves that the CMLA produces images of the same visual quality as the conventional single‐line addressing (SLA), while the power efficiency is substantially higher.
PIN OLEDs — Improved structures and materials to enhance device lifetime
Authors: Birnstock Jan , Canzler Tobias , Hofmann Michael , Lux Andrea , Murano Sven , Wellmann Philipp , Werner Ansgar
Published: January 2008

Abstract— Currently, three issues are identified that decide upon the commercial success of organic light‐emitting diodes (OLEDs), both in display and lighting applications: power efficiency, lifetime, and price competitiveness. PIN OLEDs are widely seen as the preferred way to maximize power efficiency. Here, it is reported that this concept also delivers the world longest lifetimes. For a highly efficient deep‐red PIN OLED, a half‐lifetime of 25,000 hours for a starting brightness of 10,000 cd/m2 and a minimal voltage increase over lifetime is reported. This value corresponds to more than 1 × 106 hours at 1000 cd/m2 using an exponent of n = 1.7, which was measured by driving the OLEDs at different starting luminances. Because there is no initial luminance drop, these PIN OLEDs also exhibit a very high 80% lifetime (>300,000 hours at 1000 cd/m2). New record lifetime values for blue and green will be reported as well. Additionally, further topics that have impact on the production yield and cost such as the newly developed air‐stable organic n‐doping material NDN‐26 and top‐emitting structures will be discussed.
Oxide TFT with multilayer gate insulator for backplane of AMOLED device
Authors: Lee Ho‐Nyun , Kyung Jaewoo , Sung Myeon‐Chang , Kim Do Youl , Kang Sun Kil , Kim Seong‐Joong , Kim Chang Nam , Kim Hong‐Gyu , Kim Sung‐Tae
Published: January 2008

Abstract— An indium gallium zinc oxide (IGZO) film with an amorphous phase was deposited and had a very flat morphology with a RMS value of 0.35 nm. IGZO TFTs were fabricated on a glass substrate by conventional photolithography and wet‐etching processes. IGZO TFTs demonstrated a high mobility of 124 cm2/V‐sec, a high on/off ratio of over 108, a desirable threshold voltage of 0.7 V, and a sub‐threshold swing of 0.43 V/decade. High mobility partially resulted from the fringing‐electric‐field effect that leads to an additional current flow beyond the device edges. Therefore, considering our device geometry, the actual mobility was about 100 cm2/V‐sec, and had a very low dependence on the variation of W/L (channel width and length) and thickness of the active layer. IGZO TFTs were also fabricated on a flexible metal substrate for a conformable display application. TFT devices showed an actual mobility of 72 cm2/V‐sec, a high on/off ratio of ∼107, and a sub‐threshold swing of 0.36 V/decade. There was no significant difference before, during, or after bending. Moreover, an IGZO TFT array was fabricated and a top‐emitting OLED device was successfully driven by it. Therefore, the oxide TFT could be a promising candidate as a backplane for OLED devices.
Practical CNT‐FED structure for high‐luminance character displays
Authors: Yotani Junko , Uemura Sashiro , Nagasako Takeshi , Kurachi Hiroyuki , Ezaki Tomotaka , Maesoba Tsuyoshi , Nakao Takehiro , Ito Masaaki , Sakurai Akira , Shimoda Hideo , Yamada Hiromu , Saito Yahachi
Published: January 2008

Abstract— A high‐luminance CNT‐FED character display using a simple line rib structure was constructed. The display panel had 48 × 480 dots and the subpixel pitch was 1 mm. The greatest benefit of a display using CNT technology is high luminance performance with low‐power consumption. The luminance of the green‐color dot wasca. 10,000 cd/m2 under 1/1 6 duty‐cycle driving at a 6‐kV anode voltage. The high luminance of the display panel can provide good visibility when installed even in outdoor locations, and the power consumption was ca. 4 W at the character displaying module. This, a CNT‐FED for character displays also has potential multifunctionality, which could be battery driven. It should be useful for public displays even under emergency no‐power conditions. In this work, a practical structure and process technologies for making ribs with reasonable cost were developed. The newly introduced 2‐mm‐tall line ribs as spacers were formed by using innovative production processes; i.e., the rib paste was pushed out of a multi‐slit nozzle, and the rib shape was formed by UV‐light irradiation. The developed panel structure and manufacturing processes also had the advantages of size flexibility and high production yield.
Magnetically inert medical projection system with an image‐guiding optical fiber
Authors: Riehemann Stefan , Lippmann Uwe , Notni Gunther
Published: January 2008

Abstract— A visual system for stimulating specific human brain functions inside a clinical magnetoencephalography (MEG) measurement chamber was developed. This system is based on a three‐panel LCOS projection unit and uses a 4.5‐m‐long image‐guiding optical‐fiber bundle to transfer the image into the magnetically shielded MEG measurement chamber. In addition to a proper optical system design, special attention had to be paid to all materials used inside the magnetically shielded chamber. Here, no interfering fields due to electrics or ferromagnetic materials are allowed. The system concept, optical design, and the realized prototype are presented.
Progress of LED backlights for LCDs
Authors: Anandan Munisamy
Published: January 2008

Abstract— Cold‐cathode fluorescent lamps (CCFLs) are being used for LCD backlighting and is currently the dominant technology for LCD backlighting. However, recent attention has been given to LEDs as light sources for LCD backlighting because of their (i) long life, (ii) low‐voltage operation, (iii) fast response time, and (iv) wide color gamut. This review article commences with the basics of LEDs as light sources and their limitations, followed by various backlight structures employing LEDs in cell phones, notebook computers, and LCD TVs. The description of the improvement in image quality on an LCD screen, stemming from the characteristics of LEDs, is also given. In conclusion, the possible rapid growth of LED backlights is outlined, thus gradually ending the domination of CCFL backlights.
Power savings and enhancement of gray‐scale capability of LCD TVs with an adaptive dimming technique
Authors: Shiga Tomokazu , Shimizukawa Sho , Mikoshiba Shigeo
Published: January 2008

Abstract— The luminance of a backlight unit for an LCD TV is adaptively and locally dimmed along with the input video signal in order to reduce the power consumption and also to improve the picture quality. By adopting the zero‐dimensional (0D), 1D, and 2D adaptive dimming techniques, a sample movie having 8.0% post‐gamma average picture levels (APL) could be displayed using 83%, 71%, and 50% of the original backlight power, respectively. For an adoption of the 2D dimming, an LED backlight is preferable. The adaptive‐dimming technique also allows the differential aging characteristics between the LED components and temperature dependence of color and luminance to be overcome. From simulations of a reduction in power consumption, it was found that 40 × 40 pixels is a unit of the local dimming, 30 frames for the sampling period, 24 dimming steps, and an equal‐signal‐step method for determining the dimming factor have been found to be appropriate. The gray‐scale capability of low‐luminance images can also be improved by dimming the backlight luminance and expanding the input signal. By using an LCD TV having an 8‐bit capability, an 11‐bit‐equivalent gray‐scale expression was experimentally proven.
Implementation of an LED backlight for avionics displays
Authors: Nodari Mauro , Zaraga Federico , Grassetti Riccardo
Published: January 2008

Abstract— The replacement of conventional light sources used to backlight displays with LEDs is very attractive in avionics. Today's LED technology provides devices suitable to implement display backlight sources but specific requirements need to be satisfied for avionics displays. This paper covers the development of an innovative LED backlight dedicated to avionics displays, realized in a new box geometry in order to generate more than 10,000 cd/m2 on a 6 × 5‐in. active area using less than 28 W of power.
A YC‐separation‐type projector: High dynamic range with double modulation
Authors: Kusakabe Yuichi , Kanazawa Masaru , Nojiri Yuji , Furuya Masato , Yoshimura Makato
Published: January 2008

Abstract— An experimental projector that features double modulation to obtain high‐resolution (4096 × 2160 pixels) and high‐dynamic‐range images has been developed. Although a conventional projector contains three modulators for red, green, and blue and outputs light after combining the modulated light from these three sources, our projector has an additional modulator for luminance that modulates the combined RGB modulated light. It can display high‐resolution color images by combining three low‐resolution panels for chrominance modulation and one high‐resolution panel for luminance modulation. In addition, the dynamic range is dramatically improved because the double‐modulation scheme minimizes black levels in projected images. The projector demonstrates an extremely high dynamic range of 1.1 million to 1 and 10‐bit tone reproduction.
Management of novel ecosystems: are novel approaches required?
Authors: Seastedt Timothy R , Hobbs Richard J , Suding Katharine N
Published: January 2008

Most ecosystems are now sufficiently altered in structure and function to qualify as novel systems, and this recognition should be the starting point for ecosystem management efforts. Under the emerging biogeochemical configurations, management activities are experiments, blurring the line between basic and applied research. Responses to specific management manipulations are context specific, influenced by the current status or structure of the system, and this necessitates reference areas for management or restoration activities. Attempts to return systems to within their historical range of biotic and abiotic characteristics and processes may not be possible, and management activities directed at removing undesirable features of novel ecosystems may perpetuate or create such ecosystems. Management actions should attempt to maintain genetic and species diversity and encourage the biogeochemical characteristics that favor desirable species. Few resources currently exist to support the addition of proactive measures and rigorous experimental designs to current management activities. The necessary changes will not occur without strong input from stakeholders and policy makers, so rapid information transfer and proactive research–management activities by the scientific community are needed.
Applying the Underbalanced-for-Life Philosophy to Well Construction
Authors: Bowling J. , Riyami M. , Somat E. , Vieira P.
Published: January 2008

Three years ago Petroleum Development Oman (PDO) implemented an "Underbalanced for Life" philosophy as a means to improve well and reservoir productivity. This philosophy requires not only drilling the well underbalanced but completing the well underbalanced so that only produced fluids are exposed to the reservoir.

From 2002 to 2004, the UBD campaign focused on wells and fields that had a reservoir pressure low enough to not flow to surface. This meant BHA trips and well completion operations were conducted conventionally and no special procedures and operations were required. At the end of 2004, PDO began drilling underbalanced in fields that had sufficient reservoir pressure to flow to surface.

Until recently, the only way for a drilling rig to trip pipe into and out of the well was to kill the well so that there was no surface pressure or to snub the pipe under pressure. A new alternative was identified where a down hole valve is used to lubricate pipe into and out of the well without surface pressure. To meet the philosophy of "underbalanced for life" the down hole valve was selected and new equipment, procedures and methods developed.

Early trials with the retrievable down hole valve provided sufficient success to continue drilling wells with natural flow to surface. More than 20 flowing wells have been completed underbalanced with a high rate of success.

This paper explains the well design, procedures and equipment used to implement the "Underbalanced for Life" philosophy.
Systematic Evaluation of Kuwaiti Reservoirs to Determine Optimum Candidates for Underbalanced Drilling
Authors: Al-Matar Bader , Al-Atroshi Kamal , Chetri Hom , El-Aziz Sabry Abd , Kabir Mir Md Rezaul , Shayegi Sara , Ibrahim Emad Bakri
Published: January 2008

Underbalanced drilling technology (UBD) has increased production potential from many oil and gas reservoirs worldwide. Kuwait Oil Company (KOC) decided to pilot this technology in Kuwaiti reservoirs to assess the viability of this technique and its capability to optimize production and development of their reservoirs. To maximize the potential for successful implementation, a scientifically rigorous process was implemented to evaluate the reservoir candidates.

The reservoirs include Upper Burgan, Mauddud, Tayarat, and Radhuma. Since there is a high degree of variation in reservoir quality, hydrocarbon properties, formation pressures and other properties depending on location, candidates from different locations were examined. In the first phase, a high order qualitative ranking of the candidates was performed. The basis of comparison included an examination of the reservoir and fluid properties, production data, review of the core, log and geological/geophysical data, drilling and operational information.

The ranking of the candidates was based on production potential, drilling benefits, potential for instability, early water break through, and other operational, reservoir and drilling considerations. The top-ranked candidates were examined determining the range of potential reservoir behavior during UBD and the corresponding wellbore hydraulics (drilling the well on paper) was performed.

It was concluded that UBD technology was suited for several of the reservoirs but that some of the candidates might not realize as much improvement as others to justify implementation in the first implementation stage. If UBD proves successful on the candidates chosen for the pilot study, the candidates showing a lesser degree of potential will again be considered.

This paper describes the screening methodology used and discusses the results from the candidate evaluation process.
Underbalanced Drilling of Oil Wells in Saudi Arabia: Case History and Lessons Learned
Authors: Muqeem Muhammad A. , Jarrett Clark M. , Abdul Hassan J.
Published: January 2008

Saudi Aramco started a campaign in the fall of 2004 to drill Power Water Injection (PWI) Wells underbalanced. After drilling several PWI wells, it was envisaged that adequate experience and learning curve has been established to implement the next phase of this campaign. In the 4th quarter of 2005, a three well pilot program was undertaken to plan and execute this enabling technology safely and in an environmentally safe manner in oil wells.

The primary objective of drilling these oil wells underbalanced was to demonstrate that a closed/semi-closed system can be utilized properly and safely to undertake underbalanced drilling (UBD) operations in the Ghawar field. Furthermore, the aim was also to verify whether it is possible to ship the produced sour crude to the nearby facilities without any environmental or operational concerns.

This paper summarizes Saudi Aramco's experience gained during the drilling of these three oil wells. Mechanical and hydraulic down-hole valves were utilized for tripping and stripping into and out of these wells in an underbalanced mode. It further highlights the operational complexity and the challenges faced during the implementation of this technology in a hydrocarbon bearing zone for the first time. It also elaborates on the interdisciplinary team that was instrumental behind the safe and successful implementation of underbalanced drilling.

The paper also elaborates on the lessons learned and how they were implemented continuously with regards to Health, Safety and Environmental (HSE) during the drilling operations. The long term goal was to evaluate whether the application of UBD can be extended to other asset teams/areas effectively to reap its potential benefit.
Sometimes Neglected Hydraulic Parameters of Underbalanced and Managed Pressure Drilling
Authors: Stone Charles R. "Rick" , Tian Shifeng
Published: January 2008

Successful drilling, especially in very deep wells, may be driven by hydraulic limiting parameters. Two new technologies, UnderBalanced Drilling (UBD) and Managed Pressure Drilling (MPD) have emerged as solutions to specific hydraulic issues during drilling. A hydraulic parameter can be defined as any factor, mechanical, structural or fluid that impacts the exertion of hydrostatic head on the open hole. Hydraulic parameters, as a group, must be planned for and managed during all drilling operations to prevent unwanted or unsafe conditions.

Many hydraulic parameters are documented thoroughly and therefore well-known in the upstream oil and gas industry. They include; Pump Rate; Drillstring and Hole Geometry; Mud Rheology (including surge effect, swab effect, standpipe pressure and hole cleaning); Surface Backpressure; and Rate of Penetration (ROP). These factors are commonplace and routinely addressed as part of a complete drilling program. Other hydraulic limiting parameters are lesser known and sometimes not addressed in the basis of design for unconventional drilling prospects.

It is paramount that drillers consider all hydraulic parameters that influence UBD or MPD operations or the project can end in failure or with unsuccessful consequences. This paper discusses in general some of the lesser-known hydraulic issues that might be encountered when drilling vertical wells using UBD or MPD techniques, especially to deeper horizons.
Disparities in A1C Levels Between Hispanic and Non-Hispanic White Adults With Diabetes
Authors: Kirk Julienne K. , Passmore Leah V. , Bell Ronny A. , Narayan K.M. Venkat , D'Agostino Ralph B. , Arcury Thomas A. , Quandt Sara A.
Published: January 2008

OBJECTIVE—Hispanics have higher rates of diabetes and diabetes-related complications than do non-Hispanic whites. A meta-analysis was conducted to estimate the difference between the mean values of A1C for these two groups.

RESEARCH DESIGN AND METHODS—We executed a PubMed search of articles published from 1993 through July 2007. Data sources included PubMed, Web of Science, Cumulative Index to Nursing and Allied Health, the Cochrane Library, Combined Health Information Database, and Education Resources Information Center. Data on sample size, age, sex, A1C, geographical location, and study design were extracted. Cross-sectional data and baseline data from clinical trials and cohort studies for Hispanics and non-Hispanic whites with diabetes were included. Studies were excluded if they included individuals <18 years of age or patients with pre-diabetes or gestational diabetes.

RESULTS—A total of 495 studies were reviewed, of which 73 contained data on A1C for Hispanics and non-Hispanic whites, and 11 met the inclusion criteria. Meta-analysis revealed a statistically significant mean difference (P < 0.0001) of −0.46 (95% CI −0.63 to −0.33), correlating to an ∼0.5% higher A1C for Hispanics. Grouping studies by design (cross-sectional or cohort), method of data collection for A1C (chart review or blood sampling), and care type (managed or nonmanaged) yielded similar results.

CONCLUSIONS—In this meta-analysis, A1C was ∼0.5% higher in Hispanic patients with diabetes than in non-Hispanic patients. Understanding the reasons for this disparity should be a focus for future research.
Effects of Age, Time Period, and Birth Cohort on the Prevalence of Diabetes and Obesity in Korean Men
Authors: Kwon Jin-Won , Song Yun-mi , Park Hye soon , Sung Joohon , Kim Ho , Cho Sung-il
Published: January 2008

OBJECTIVE—We examined changes in the prevalence of diabetes, obesity, and overweight in 412,881 Korean men in birth cohorts from 1933 to 1972 over 8 years from 1992 to 2000 and separately analyzed the effects of age, time period, and birth cohort.

RESEARCH DESIGN AND METHODS—The study included male employees of Korean government organizations and schools who were between 20 and 59 years of age in 1992. Diabetes was diagnosed on the basis of self-reports in 1992 or fasting blood glucose levels (≥126 mg/ml, 7.0 mmol/l). The age-period-cohort model was used to estimate the effects of age, time period, and birth cohort.

RESULTS—In Korean male birth cohorts from 1933 to 1972, the age-specific prevalence of diabetes, obesity, and overweight in men aged 28–59 years increased annually by 0.41% (3.03 to 6.29%), 0.18% (0.70 to 2.16%), and 1.49% (23.48 to 35.41%), respectively, from 1992 to 2000. The relative change in diabetes was largest among the younger cohorts (>400% increase over 8 years) and corresponded to the change in obesity. Apart from the contribution of age, clear cohort and period effects were evident for diabetes, although the magnitude of the effect was slightly less than that for obesity.

CONCLUSIONS—Prevention of diabetes through the control of obesity, particularly in young men, clearly needs to be emphasized.
Glucose Indices, Health Behaviors, and Incidence of Diabetes in Australia
Authors: Magliano Dianna J. , Barr Elizabeth L.M. , Zimmet Paul Z. , Cameron Adrian J. , Dunstan David W. , Colagiuri Stephen , Jolley Damien , Owen Neville , Phillips Patrick , Tapp Robyn J. , Welborn Tim A. , Shaw Jonathan E.
Published: January 2008

OBJECTIVE—This national, population-based study reports diabetes incidence based on oral glucose tolerance tests (OGTTs) and identifies risk factors for diabetes in Australians.

RESEARCH DESIGN AND METHODS—The Australian Diabetes, Obesity and Lifestyle Study followed-up 5,842 participants over 5 years. Normal glycemia, impaired fasting glucose (IFG), impaired glucose tolerance (IGT), and diabetes were defined using World Health Organization criteria.

RESULTS—Age-standardized annual incidence of diabetes for men and women was 0.8% (95% CI 0.6–0.9) and 0.7% (0.5–0.8), respectively. The annual incidence was 0.2% (0.2–0.3), 2.6% (1.8–3.4), and 3.5% (2.9–4.2) among those with normal glycemia, IFG, and IGT, respectively, at baseline. Among those with IFG, the incidence was significantly higher in women (4.0 vs. 2.0%), while among those with IGT, it was significantly higher in men (4.4 vs. 2.9%). Using multivariate logistic regression, hypertension (odds ratio 1.64 [95% CI 1.17–2.28]), hypertriglyceridemia (1.46 [1.05–2.02]), log fasting plasma glucose (odds ratio per 1 SD 5.25 [95% CI 3.98–6.92]), waist circumference (1.26 [1.08–1.48]), smoking (1.70 [96% CI 1.11–2.63]), physical inactivity (1.56 [1.12–2.16]), family history of diabetes (1.82 [1.30–2.52]), and low education level (1.85 [1.04–3.31]) were associated with incident diabetes. In age- and sex-adjusted models, A1C was a predictor of diabetes in the whole population, in those with normal glycemia, and in those with IGT or IFG.

CONCLUSIONS—Diabetes incidence is 10–20 times greater in those with IGT or IFG than those with normal glycemia. Measures of glycemia, A1C, metabolic syndrome components, education level, smoking, and physical inactivity are risk factors for diabetes.
Body Iron Stores and Dietary Iron Intake in Relation to Diabetes in Adults in North China
Authors: Luan De Chun , Li Hui , Li Sui Jing , Zhao Zhuo , Li Xin , Liu Zhong Mei
Published: January 2008

OBJECTIVE—To evaluate the association between body iron stores, dietary iron intake, and risk of diabetes in northern China.

RESEARCH DESIGN AND METHODS—The data of a cross-sectional household survey in 2002 in Liaoning Province in northern China was used. The final sample in our study contained 2,997 subjects aged ≥18 years. Fasting plasma glucose and serum ferritin were measured. Dietary information was collected by 3-day food records.

RESULTS—Serum ferritin was associated with elevated risk of diabetes even adjusted for age, sex, nondietary factors, and dietary factors. No association among total iron intake, nonheme iron intake, and diabetes risk was found. However, higher heme iron intake was significantly associated with elevated risk of diabetes after adjusting for known factors.

CONCLUSIONS—In Chinese, associations among higher serum ferritin level, higher heme iron intake, and elevated risk of diabetes were found.
Perception of Neighborhood Problems, Health Behaviors, and Diabetes Outcomes Among Adults With Diabetes in Managed Care
Authors: Gary Tiffany L. , Safford Monika M. , Gerzoff Robert B. , Ettner Susan L. , Karter Andrew J. , Beckles Gloria L. , Brown Arleen F.
Published: January 2008

OBJECTIVE—Recent data suggest that residential environment may influence health behaviors and outcomes. We assessed whether perception of neighborhood problems was associated with diabetes behaviors and outcomes.

RESEARCH DESIGN AND METHODS—This cross-sectional analysis included 7,830 diabetic adults enrolled in Translating Research Into Action for Diabetes, a study of diabetes care and outcomes in managed care settings. Perception of neighborhood problems was measured using a summary score of participants’ ratings of crime, trash, litter, lighting at night, and access to exercise facilities, transportation, and supermarkets. Outcomes included health behaviors and clinical outcomes. Hierarchical regression models were used to account for clustering of patients within neighborhoods and to adjust for objective neighborhood socioeconomic status (percentage living in poverty) and potential individual-level confounders (age, sex, race/ethnicity, education, income, comorbidity index, and duration of diabetes).

RESULTS—After adjustment, residents of neighborhoods in the lowest tertile (most perceived problems) reported higher rates of current smoking (15 vs. 11%) than those in the highest tertile and had slightly lower participation in any weekly physical activity (95 vs. 96%). In addition, their blood pressure control was worse (25 vs. 31% <130/80 mmHg), and their Short Form 12 scores were slightly lower (44 vs. 46 units for emotional well-being and 43 vs. 44 units for physical well-being); all P < 0.01.

CONCLUSIONS—Neighborhood problems were most strongly associated with more smoking and higher blood pressure, both of which have significant implications for cardiovascular risk. Potential mechanisms that explain these associations should be further explored in longitudinal studies.
High Serum Uric Acid as a Novel Risk Factor for Type 2 Diabetes
Authors: Dehghan Abbas , van Hoek Mandy , Sijbrands Eric J.G. , Hofman Albert , Witteman Jacqueline C.M.
Published: January 2008

OBJECTIVE—To investigate the association between serum uric acid level and risk of type 2 diabetes.

RESEARCH DESIGN AND METHODS—The population for analysis consisted of 4,536 subjects free from diabetes at baseline. During a mean of 10.1 years of follow-up, 462 subjects developed diabetes.

RESULTS—The age- and sex-adjusted hazard ratios (HRs) (95% CIs) for diabetes were 1.30 (0.96–1.76) for the second, 1.63 (1.21–2.19) for the third, and 2.83 (2.13–3.76) for the fourth quartile of serum uric acid, in comparison with the first quartile. After adjustment for BMI, waist circumference, systolic and diastolic blood pressure, and HDL cholesterol, the HRs decreased to 1.08 (0.78–1.49), 1.12 (0.81–1.53), and 1.68 (1.22–2.30), respectively.

CONCLUSIONS—The results of this population-based study suggest that serum uric acid is a strong and independent risk factor for diabetes.
Detection of a Meal Using Continuous Glucose Monitoring
Authors: Dassau Eyal , Bequette B. Wayne , Buckingham Bruce A. , Doyle Francis J.
Published: January 2008

OBJECTIVE—The purpose of this study was to introduce a novel meal detection algorithm (MDA) to be used as part of an artificial β-cell that uses a continuous glucose monitor (CGM).

RESEARCH DESIGN AND METHODS—We developed our MDA on a dataset of 26 meal events using records from 19 children aged 1–6 years who used the MiniMed CGMS Gold. We then applied this algorithm to CGM records from a DirecNet pilot study of the FreeStyle Navigator continuous glucose sensor. During a research center admission, breakfast insulin was withheld for 1 h, and discrete glucose levels were obtained every 10 min after the meal.

RESULTS—Based on the Navigator readings, the MDA detected a meal at a mean time of 30 min from the onset of eating, at which time the mean serum glucose was 21 mg/dl above baseline (range 2–36 mg/dl), and >90% of meals were detected before the glucose had risen 40 mg/dl from baseline.

CONCLUSIONS—The MDA will enable automated insulin dosing in response to meals, facilitating the development of an artificial pancreas.
Evaluation of a System for Automatic Detection of Diabetic Retinopathy From Color Fundus Photographs in a Large Population of Patients With Diabetes
Authors: Abràmoff Michael D. , Niemeijer Meindert , Suttorp-Schulten Maria S.A. , Viergever Max A. , Russell Stephen R. , van Ginneken Bram
Published: January 2008

OBJECTIVE—To evaluate the performance of a system for automated detection of diabetic retinopathy in digital retinal photographs, built from published algorithms, in a large, representative, screening population.

RESEARCH DESIGN AND METHODS—We conducted a retrospective analysis of 10,000 consecutive patient visits, specifically exams (four retinal photographs, two left and two right) from 5,692 unique patients from the EyeCheck diabetic retinopathy screening project imaged with three types of cameras at 10 centers. Inclusion criteria included no previous diagnosis of diabetic retinopathy, no previous visit to ophthalmologist for dilated eye exam, and both eyes photographed. One of three retinal specialists evaluated each exam as unacceptable quality, no referable retinopathy, or referable retinopathy. We then selected exams with sufficient image quality and determined presence or absence of referable retinopathy. Outcome measures included area under the receiver operating characteristic curve (number needed to miss one case [NNM]) and type of false negative.

RESULTS—Total area under the receiver operating characteristic curve was 0.84, and NNM was 80 at a sensitivity of 0.84 and a specificity of 0.64. At this point, 7,689 of 10,000 exams had sufficient image quality, 4,648 of 7,689 (60%) were true negatives, 59 of 7,689 (0.8%) were false negatives, 319 of 7,689 (4%) were true positives, and 2,581 of 7,689 (33%) were false positives. Twenty-seven percent of false negatives contained large hemorrhages and/or neovascularizations.

CONCLUSIONS—Automated detection of diabetic retinopathy using published algorithms cannot yet be recommended for clinical practice. However, performance is such that evaluation on validated, publicly available datasets should be pursued. If algorithms can be improved, such a system may in the future lead to improved prevention of blindness and vision loss in patients with diabetes.
Soluble CD36 and Risk Markers of Insulin Resistance and Atherosclerosis Are Elevated in Polycystic Ovary Syndrome and Significantly Reduced During Pioglitazone Treatment
Authors: Glintborg Dorte , Højlund Kurt , Andersen Marianne , Henriksen Jan Erik , Beck-Nielsen Henning , Handberg Aase
Published: January 2008

OBJECTIVE—We investigated the relation between soluble CD36 (sCD36), risk markers of atherosclerosis and body composition, and glucose and lipid metabolism in polycystic ovary syndrome (PCOS).

RESEARCH DESIGN AND METHODS—Thirty PCOS patients were randomized to 30 mg/day pioglitazone or placebo for 16 weeks. Fourteen weight-matched healthy female subjects were included as control subjects. sCD36, oxidized LDL (oxLDL), high-sensitivity C-reactive protein (hsCRP), interleukin (IL)-6, euglycemic-hyperinsulinemic clamps, and whole-body dual-energy X-ray absorptiometry scans were performed.

RESULTS—sCD36 (2.87 relative units [0.88–9.36] vs. 1.67 relative units [0.72–3.89]), oxLDL (44.9 units/l [26.9–75.1] vs. 36.1 units/l [23.4–55.5]), and hsCRP (0.26 mg/dl [0.03–2.41] vs. 0.12 mg/dl [0.02–0.81]) were significantly increased in PCOS patients versus control subjects (geometric mean ± 2 SD). In PCOS, positive correlations were found between central fat mass and sCD36 (r = 0.43), hsCRP (r = 0.43), and IL-6 (r = 0.42) (all P < 0.05). After adjusting for fat mass, sCD36 and oxLDL correlated inversely with measures of insulin-stimulated glucose metabolism and positively with lipid oxidation during insulin stimulation in PCOS patients and control subjects (n = 44). sCD36 and oxLDL were significant independent predictors of glucose and lipid metabolism, whereas hsCRP and IL-6 showed no significant contribution. Following pioglitazone treatment, insulin sensitivity increased, whereas sCD36 (3.21 relative units [0.76–13.6] vs. 2.33 relative units [0.84–6.46]) and hsCRP decreased (P < 0.05). No significant changes were measured in body composition.

CONCLUSIONS—sCD36 and oxLDL correlated with measures of insulin sensitivity independent of central fat mass. Pioglitazone treatment reduced sCD36 while improving insulin-stimulated glucose metabolism, further supporting the association between sCD36 and insulin resistance in PCOS.
Diabetes in U.S. Nursing Homes, 2004
Authors: Resnick Helaine E. , Heineman Janice , Stone Robyn , Shorr Ronald I.
Published: January 2008

The 2004 National Nursing Home Survey collected cross-sectional data for 11,939 nursing home residents aged ≥65 years representing ∼1.32 million individuals. That year, 24.6% of nursing home residents had diabetes as a primary admission and/or current diagnosis. Diabetes was present in 22.5 and 35.6% of white and nonwhite residents, respectively. Diabetic residents were admitted more often from acute care hospitals (42.5 vs. 35.3%), were more likely to have a length of stay ≤100 days (22.6 vs. 20.1%), and took more medications (10.3 vs. 8.4). Diabetic residents had 39% higher odds of having emergency department visits in the previous 90 days and 56% higher odds of having a pressure ulcer at the time of the survey. In the U.S. in 2004, one in four nursing home residents aged ≥65 years had diabetes, and diabetic residents had increased odds of several unfavorable outcomes that are important for care planning.
Isolated Impaired Fasting Glucose and Peripheral Insulin Sensitivity
Authors: Kim Sun H. , Reaven Gerald M.
Published: January 2008

OBJECTIVE—In a recent consensus statement, the American Diabetes Association (ADA) concluded that individuals with impaired fasting glucose (IFG) have “normal muscle insulin sensitivity.” To subject this conclusion to further validation, we evaluated the relationship between glucose tolerance categories and peripheral insulin sensitivity in a large nondiabetic population.

RESEARCH DESIGN AND METHODS—Insulin sensitivity was directly quantified by determining the steady-state plasma glucose (SSPG) concentration during an insulin suppression test in 446 nondiabetic individuals divided into four groups: normal glucose tolerance (NGT, n = 318), isolated IFG (n = 63), isolated impaired glucose tolerance (IGT, n = 33), and combined IFG and IGT (IFG/IGT, n = 32).

RESULTS—Insulin sensitivity was significantly different in all three groups with pre-diabetes (IFG, IGT, IFG/IGT) as compared with NGT (P < 0.05). Using tertiles of SSPG concentration in the NGT group as operational definitions of insulin resistance (highest tertile) and insulin sensitivity (lowest tertile), there was considerable heterogeneity within the pre-diabetic groups. Thus, 57% of IFG individuals were insulin resistant, and 13% were insulin sensitive. The IFG/IGT group was most homogeneous, with 94% classified as insulin resistant and only 3% as insulin sensitive.

CONCLUSIONS—Peripheral insulin sensitivity varies considerably in nondiabetic individuals, with IFG individuals showing the most heterogeneity within the pre-diabetes group. We believe that this heterogeneity in insulin sensitivity, and the relatively few patients in whom insulin sensitivity has been measured directly in the past, explain the discrepancy between our findings and those of the recent ADA consensus statement.
Effect of Supplementation of Coccinia cordifolia Extract on Newly Detected Diabetic Patients
Authors: Kuriyan Rebecca , Rajendran Ramaswamy , Bantwal Ganapathi , Kurpad Anura V.
Published: January 2008

OBJECTIVE—Coccinia indica (synonym Coccinia cordifolia), an herb growing abundantly in India, has been used in traditional treatment of diabetes. However, carefully controlled studies of its efficacy are lacking. This study aimed to evaluate the effectiveness of Coccinia cordifolia on blood glucose levels of incident type 2 diabetic patients requiring only dietary or lifestyle modifications.

RESEARCH DESIGN AND METHODS—The study was a double-blind, placebo-controlled, randomized trial. Sixty incident type 2 diabetic subjects (aged 35–60 years) were recruited from St. Johns Medical College Hospital, Bangalore, India. The subjects were randomly assigned into the placebo or experimental group and were provided with 1 g alcoholic extract of the herb for 90 days. Anthropometric, biochemical, dietary, and physical activity assessment were carried out at baseline and were repeated at days 45 and 90 of the study. All subjects were provided with standard dietary and physical activity advice for blood sugar control.

RESULTS—There was a significant decrease in the fasting, postprandial blood glucose and A1C of the experimental group compared with that of the placebo group. The fasting and postprandial blood glucose levels of the experimental group at day 90 significantly decreased, by 16 and 18%, respectively. There were no significant changes observed in the serum lipid levels.

CONCLUSIONS—This study suggests that Coccinia cordifolia extract has a potential hypoglycemic action in patients with mild diabetes. However, further studies are needed to elucidate mechanisms of action.
Decreased Non–Insulin-Dependent Glucose Clearance Contributes to the Rise in Fasting Plasma Glucose in the Nondiabetic Range
Authors: Jani Rucha , Molina Marjorie , Matsuda Masafumi , Balas Bogdan , Chavez Alberto , DeFronzo Ralph A. , Abdul-Ghani Muhammad
Published: January 2008

OBJECTIVE—To assess the contribution of decreased glucose clearance to the rise in fasting plasma glucose (FPG) in the nondiabetic range.

RESEARCH DESIGN AND METHODS—A total of 120 subjects with normal glucose tolerance received an oral glucose tolerance test and euglycemic insulin clamp with 3-[3H]glucose. The basal and insulin-stimulated rates of glucose appearance, glucose disappearance, and glucose clearance and the basal hepatic insulin resistance index were calculated. Simple Pearson's correlation was used to assess the relationship between variables.

RESULTS—The increase in FPG (range 75–125 mg/dl) correlated (r = 0.32, P < 0.0001) with the increase in BMI (20–50 kg/m2). The fasting plasma insulin (FPI) concentration also increased progressively with the increase in BMI (r = 0.62, P < 0.0001). However, despite increasing FPI, the basal glucose clearance rate declined and correlated with the increase in BMI (r = −0.56, P < 0.0001). Basal hepatic glucose production (HGP) decreased with increasing BMI (r = −0.51, P < 0.0001) and correlated inversely with the increase in FPI (r = −0.32, P < 0.0001). The hepatic insulin resistance (basal HGP × FPI) increased with rising BMI (r = 0.52, P < 0.0001). During the insulin clamp, glucose disposal declined with increasing BMI (r = −0.64, P < 0.0001) and correlated with the basal glucose clearance (r = 0.39, P < 0.0001).

CONCLUSIONS—These results demonstrate that in nondiabetic subjects, rising FPG is associated with a decrease (not an increase) in basal hepatic glucose production and is explained by a reduction in glucose clearance.
Impact of Autonomic Neuropathy on Left Ventricular Function in Normotensive Type 1 Diabetic Patients
Authors: Karamitsos Theodoros D. , Karvounis Haralambos I. , Didangelos Triantafyllos , Parcharidis Georgios E. , Karamitsos Dimitrios T.
Published: January 2008

Cardiovascular autonomic neuropathy (CAN) is one of the most serious complications of diabetes and has been weakly linked with left ventricular (LV) diastolic dysfunction. Previous studies that explored this association either suffer from inadequate definition of CAN or have mainly used conventional Doppler or nuclear techniques to investigate LV diastolic function. Tissue Doppler imaging (TDI) has evolved as a new quantitative tool for the assessment of cardiac systolic function, diastolic function, and the hemodynamics of LV filling. We sought to investigate conventional and TDI-derived indexes of LV systolic and diastolic function in type 1 diabetic patients with and without CAN and also in normal control subjects. Our findings suggest that the presence of CAN seems to have an additive effect on LV diastolic dysfunction in type 1 diabetes.
Bone Fractures and Hypoglycemic Treatment in Type 2 Diabetic Patients
Authors: Monami Matteo , Cresci Barbara , Colombini Angela , Pala Laura , Balzi Daniela , Gori Francesca , Chiasserini Veronica , Marchionni Niccolò , Rotella Carlo Maria , Mannucci Edoardo
Published: January 2008

OBJECTIVE—Hypoglycemic treatments could modulate the risk for fractures in many ways. Most studies have not explored the effect on the incidence of bone fractures of individual oral hypoglycemic agents, rather all oral treatments as a whole. The aim of this case-control study, nested within a retrospective cohort, is the assessment of the risk for bone fractures associated with exposure to insulin or different oral hypoglycemic agents.

RESEARCH DESIGN AND METHODS—A case-control study nested within a cohort of 1,945 diabetic outpatients with a follow-up of 4.1 ± 2.3 years was performed, comparing 83 case subjects of bone fractures and 249 control subjects matched for age, sex, duration of diabetes, BMI, A1C, comorbidity, smoking, and alcohol abuse. Exposure to hypoglycemic drugs during the 10 years preceding the event (or matching index date) was assessed.

RESULTS—In a model including treatment with insulin secretagogues metformin and insulin for at least 36 months during the previous 10 years, no significant association was observed between bone fractures and medications. In an alternative model considering treatments at the time of fracture, insulin treatment was significantly associated with bone fractures in men (OR 3.20 [95% CI 1.32–7.74]) but not in women (1.41 [0.73–2.73]).

CONCLUSIONS—Insulin-sensitizing treatment with metformin is not associated with a higher incidence of bone fractures, suggesting that the negative effect of thiazolidinediones is due to a specific action on bone metabolism rather a reduction of insulinemia. Conversely, current treatment with insulin increases the risk of fractures; at the same time, exposure to this agent in the longer term does not appear to affect bone frailty.
Aspirin and Mortality in Patients With Diabetes Sustaining Acute Coronary Syndrome
Authors: Cubbon Richard M. , Gale Christopher P. , Rajwani Adil , Abbas Afroze , Morrell Christine , Das Raj , Barth Julian H. , Grant Peter J. , Kearney Mark T. , Hall Alistair S.
Published: January 2008

OBJECTIVE—We sought to compare mortality reduction associated with secondary prevention in patients with and without diabetes after acute coronary syndrome (ACS).

RESEARCH DESIGN AND METHODS—We conducted a cohort study involving 2,499 patients with ACS recruited from 11 U.K. hospitals. Multivariable analysis comparing all-cause mortality risk reduction associated with pharmacologic agents in patients with and without diabetes.

RESULTS—Aspirin was not associated with significant mortality benefit in diabetes sufferers (95% CI 0.50–1.08); nondiabetic patients derived a 48% mortality reduction (P < 0.001). The interaction between diabetes and aspirin use was statistically significant (P = 0.037), indicating that patients with diabetes experience less effective mortality reduction from aspirin use.

CONCLUSIONS—Aspirin, but not other secondary prevention agents, is associated with less effective mortality reduction in patients with diabetes and unstable coronary artery disease.
Quantifying the Impact of a Short-Interval Interruption of Insulin-Pump Infusion Sets on Glycemic Excursions
Authors: Zisser Howard
Published: January 2008

This prospective, open-label study was designed to measure the impact of short-term infusion-set disconnects on glucose levels. Continuous subcutaneous insulin infusion therapy allows for uninterrupted delivery of insulin. Patients disconnect their insulin pumps from their infusion sets when showering, swimming, exercising, or during intimate moments. Interrupting insulin infusion results in cessation of basal insulin delivery. Nineteen subjects with type 1 diabetes were studied on two separate in-clinic days. One hour after arriving at the clinic in a fasting state, subjects either temporarily disconnected their infusion sets from their pumps, interrupting basal insulin infusion for 30 min, or, on a separate day, changed their infusion sets. Glucose levels were monitored for an additional 4 h on both occasions. Changing infusion sets did not affect short-term glucose control. However, the 30-min interruption of basal insulin infusion resulted in significant glucose elevation; ∼1 mg/dl for each minute basal insulin infusion was interrupted.
Impact of Diabetes on Physical Function in Older People
Authors: Sinclair Alan J. , Conroy Simon P. , Bayer Antony J.
Published: January 2008

OBJECTIVE—To explore the nature of functional impairment in older people with diabetes.

RESEARCH DESIGN AND METHODS—A population-based case-control study with detailed assessment of diabetes and functional status was undertaken.

RESULTS—Altogether, 403 case subjects and 403 matched control subjects were studied (median age 75 years, 51% female). Subjects with diabetes had more comorbidities than control subjects (mean 2.5 vs. 1.9, P < 0.0001) and were more likely to have severe functional impairment (4 vs. 1%, Barthel score <5, P < 0.001). Health status pertaining to physical function was reduced in case subjects (SF36 60 vs. 40, P < 0.0001). In a multivariate model controlling for age, hypertension, cerebrovascular disease, chronic obstructive pulmonary disease, cancer, osteoarthritis, and dementia, diabetes remained significantly associated with mobility limitation (odds ratio 2.1, P < 0.001).

CONCLUSIONS—Older people with diabetes have considerable functional impairment associated with reduced health status. This population may benefit from comprehensive geriatric assessment and tailored diabetes management.