WorldWideScience
1

Mechanistic fracture criteria for the failure of human cortical bone  

Energy Technology Data Exchange (ETDEWEB)

A mechanistic understanding of fracture in human bone is critical to predicting fracture risk associated with age and disease. Despite extensive work, a mechanistic framework for describing how the underlying microstructure affects the failure mode in bone is lacking.

2002-12-13

2

Prevalence of Early and Late Age-Related Macular Degeneration in India: The INDEYE Study  

UK PubMed Central (United Kingdom)

Purpose.To estimate the prevalence of early and late age-related macular degeneration (AMD) in India.Methods.Of 7518 people aged 60 years and older...Full Text Available

2010-02-01

3

Early Changes in Bone Specific Turnover Markers During the Healing Process After Vertebral Fracture  

UK PubMed Central (United Kingdom)

Background:The present study measured longitudinal changes in bone turnover markers in elderly patients with vertebral fracture and investigated the relationship among bone turnover...Full Text Available

4

Estrogen and raloxifene improve metaphyseal fracture healing in the early phase of osteoporosis. A new fracture-healing model at the tibia in rat  

British Library Electronic Table of Contents (United Kingdom)

Background Fracture healing in osteoporosis is delayed. Quality and speed of fracture healing in osteoporotic fractures are crucial with regard to the outcome of patients. The question arises whether established antiosteoporotic drugs can further improve fracture healing. Materials and methods Osteoporosis manifests predominantly in the metaphyseal bone. Nevertheless, an established metaphyseal fracture model is lacking. A standardized metaphyseal fracture-healing model with stable plate fixation was developed for rat tibiae. The healing process was analyzed by biomechanical, gene expression, and histomorphometric methods in ovariectomized (OVX) and sham-operated rats (SHAM), compared to standardized estrogen (E)- and raloxifene (R)-supplemented diets. Results Estrogen and raloxifene impro...

2010-01-01

5

For early diagnosis of the fracture healing, nonunion and avascular necorsis  

Energy Technology Data Exchange (ETDEWEB)

Complications of non-union and avascular necrosis during fracture healing process are the most important problems. Early detection of the evidence of non-union and avascular necrosis and follow-up study of fracture healing process will reduce complications and sequellae in fracture patients. Femoral neck and tibial shaft are the most important fracture sites where non-union and/or avascular necorsis are frequently developed. Osteomedullography was performed in 30 cases of fracture, 21 femoral neck, 8 tibial shafts and 1 talar neck, in the Department of Radiology of national Medical Center during the period form August 1977 to March 1981. The following results were obtained: 1. 16 patients of femoral neck fracture were performed osteomedullography one. Non-union showing no crossing vein through the fracture site was noted ...

1981-09-15

6

Effect of orientation on the in vitro fracture toughness ofdentin: The role of toughening mechanisms  

Energy Technology Data Exchange (ETDEWEB)

A micro-mechanistic understanding of bone fracture thatencompasses how cracks interact with the underlying microstructure anddefines their local failure mode is lacking, despite extensive research nthe response of bone to a variety of factors like aging, loading, and/ordisease.

2003-01-28

8

Effect of Aging on the Toughness of Human Cortical Bone: Evaluation by R-Curves  

Energy Technology Data Exchange (ETDEWEB)

Age-related deterioration of the fracture properties of bone, coupled with increased life expectancy, are responsible for increasing incidence of bone fracture in the elderly, and hence, an understanding of how its fracture properties degrade with age is essential. The present study describes ex vivo fracture experiments to quantitatively assess the effect of aging on the fracture toughness properties of human cortical bone in the longitudinal direction. Because cortical bone exhibits rising crack-growth resistance with crack extension, unlike most previous studies the toughness is evaluated in terms of resistance-curve (R-curve) behavior, measured for bone taken from wide range of age groups (34-99 years). Using this approach, both the ex vivo crack-initiation and crack-growth toughness are ...

2004-10-08

9

To study the role of dynamic magnetic resonance imaging in assessing the femoral head vascularity in intracapsular femoral neck fractures  

Energy Technology Data Exchange (ETDEWEB)

Intracapsular femoral neck fractures remain unsolved fractures even after improvement in techniques of diagnosis and internal fixation. Individuals who sustain displaced femoral neck fractures are at high risk of developing avascular necrosis and non-union. Although several methods for predicting the viability of femoral head have been reported, they are not effective or widely used because of unreliability, potential complications and technical difficulties. Dynamic MRI was introduced in the recent past as a simple, non-invasive technique to predict the femoral head viability after the femoral neck fractures. In this study role of dynamic MRI was studied in 30 patients with 31 intracapsular femoral neck fractures. Fractures were divided in to three types according to dynamic curve patterns on MRI evaluation and were followed up for 6 months to 2 years to ...

2010-09-15

10

To study the role of dynamic magnetic resonance imaging in assessing the femoral head vascularity in intracapsular femoral neck fractures  

International Nuclear Information System (INIS)

Intracapsular femoral neck fractures remain unsolved fractures even after improvement in techniques of diagnosis and internal fixation. Individuals who sustain displaced femoral neck fractures are at high risk of developing avascular necrosis and non-union. Although several methods for predicting the viability of femoral head have been reported, they are not effective or widely used because of unreliability, potential complications and technical difficulties. Dynamic MRI was introduced in the recent past as a simple, non-invasive technique to predict the femoral head viability after the femoral neck fractures. In this study role of dynamic MRI was studied in 30 patients with 31 intracapsular femoral neck fractures. Fractures were divided in to three types according to dynamic curve patterns on MRI evaluation and were followed up for 6 months to 2 years to ...

2010-09-01

11

Effect of mean stress (stress ratio) and aging on fatigue-crack growth in a metastable beta titanium alloy, Ti-10V-2Fe-3Al  

International Nuclear Information System (INIS)

The effect of mean stress, or the stress ratio (R), on the fatigue-crack growth (FCG) behavior of #alpha#-aged and #omega#-aged microstructures of the beta titanium alloy Ti-10V-2Fe-3Al was investigated. While the mean stress had a negligible effect on the FCG behavior of the #alpha#-aged microstructure, a strong effect was observed in the #omega#-aged microstructure. In particular, the values of the threshold stress-intensity range (#DELTA#K_t_h) exhibited a strong dependence on R in the #omega#-aged microstructure, while this dependence was weak in the #alpha#-aged microstructure. These effects seem to arise primarily from fracture-surface roughness-induced crack closure. The crack closure levels for the #alpha#-aged microstructure were found to be very low compared to those for the #omega#-aged ...

2000-03-01

12

Radionuclide scintimetry for diagnosis of complications following femoral neck fracture  

Energy Technology Data Exchange (ETDEWEB)

A scintimetric study using Tc-99m MDP was made of 54 patients with delayed union, nonunion, or late segmental collapse of the femoral head, 4-92 months after femoral neck fracture. In radiographically verified collapse, the radionuclide uptake ratio between the femoral head on the fractured and on the intact side (HHR) was significantly higher than in fractures resulting in delayed union or nonunion. On the basis of scintimetric and radiographic findings, the patients with healing disturbances could be divided into three groups, characterized by the following features: (1) Satisfactory post-reduction position of the fracture without subsequent redisplacement and a high HHR, which as a rule turned out to be delayed union; (2) The same radiographic pattern but with a lower HHR, which in most cases resulted in nonunion; (3) Inadequate reduction or early redisplacement of the ...

1984-01-01

13

Risedronate Prevents Early Radiation-Induced Osteoporosis in Mice at Multiple Skeletal Locations  

UK PubMed Central (United Kingdom)

IntroductionIrradiation of normal, non-malignant bone during cancer therapy can lead to atrophy and increased risk of fracture at several skeletal sites, particularly...Full Text Available

2010-01-01

14

Early Post-operative Periprosthetic Femur Fracture in the Presence of a Non-cemented Tapered Wedge Femoral Stem  

UK PubMed Central (United Kingdom)

Non-cemented femoral fixation in hip arthroplasty has become the standard of practice in the USA. However, recent literature has brought attention to an increasing incidence of periprosthetic femur...Full Text Available

2010-09-01

15

In Vitro Fracture of Human Cortical Bone: Local Fracture Criteria and Toughening Mechanisms  

Energy Technology Data Exchange (ETDEWEB)

A micro-mechanistic understanding of bone fracture that encompasses how cracks interact with the underlying microstructure and defines their local failure mode is lacking, despite extensive research on the response of bone to a variety of factors like aging, loading, and/or disease. Micro-mechanical models for fracture incorporating such local failure criteria have been widely developed for metallic and ceramic materials systems; however, few such deliberations have been undertaken for the fracture of bone. In fact, although the fracture event in mineralized tissues such as bone is commonly believed to be locally strain controlled, until recently there has been little experimental evidence to support this widely held belief. In the present study, a series of in vitro experiments involving a double-notch bend test geometry are performed in order to shed further light on the nature of ...

2004-08-18

16

Pioneering the nuclear age  

Energy Technology Data Exchange (ETDEWEB)

This paper reviews the historical aspects of nuclear physics. The scientific aspects of the early transuranium elements are discussed and arms control measures are reviewed. 11 refs., 14 figs. (LSP)

1988-09-01

17

Evolution of age at menarche and at onset of regular cycling in a large cohort of French women  

UK PubMed Central (United Kingdom)

BackgroundEarly exposure to ovarian hormones is considered to increase breast cancer incidence. The age at which the ovaries become functional is thus important.Full Text Available

2002-01-01

18

Avascular necrosis associated with nailing of femoral neck fracture  

Energy Technology Data Exchange (ETDEWEB)

Two patients with femoral neck fractures, one displaced and one undisplaced, are presented. Preoperative intravital staining with tetracycline and Tc-MDP scintimetry both showed intact femoral head circulation while Tc-MDP-scintimetry 1 week after operation showed pronounced circulatory deficiency. Sr/sup 85/-scintimetry performed at the same time was inconclusive. Segmental collapse was observed radiographically, 8 and 12 months postoperatively. The major vascular injury resulting in avascularity most probably occured during the procedure of osteosynthesis, and Tc-MDP-scintimetry was found suitable for early postoperative recognition of avascular necrosis in both fractures.

1983-01-01

19

Avascular necrosis associated with nailing of femoral neck fracture  

International Nuclear Information System (INIS)

Two patients with femoral neck fractures, one displaced and one undisplaced, are presented. Preoperative intravital staining with tetracycline and Tc-MDP scintimetry both showed intact femoral head circulation while Tc-MDP-scintimetry 1 week after operation showed pronounced circulatory deficiency. SR"8"5-scintimetry performed at the same time was inconclusive. Segmental collapse was observed radiographically, 8 and 12 months postoperatively. The major vascular injury resulting in avascularity most probably occured during the procedure of osteosynthesis, and Tc-MDP-scintimetry was found suitable for early postoperative recognition of avascular necrosis in both fractures. (author).

20

Rest life time management of Kozloduy NPPP Unit 3 and 4  

International Nuclear Information System (INIS)

The radiation life time of reactor pressure vessel (RPV) is the most important limiting factor for the term of exploitation of the whole power unit. The main degradation mechanism of RPV metal is the neutron induced embrittlement. Processes of radiation ageing running in RPV metal lead to fracture toughness decrease and to increased probability of brittle fracture of the vessel under thermal shocks. This explains the importance of RPV integrity assessment and rest life time management

2002-11-04

21

Inguino-scrotal hernia detection in the early phase of a bone scan  

International Nuclear Information System (INIS)

A large inguino-scrotal hernia was detected in the early phase of a radionuclide bone scan performed for evaluation of a femoral neck fracture not visualized on plain x-rays. The patient was administered 1 GBq of Scrotal scintigraphy using "9"9"mTc-MDP and a regional three-phase bone scan of the pelvis, hips and proximal femora was obtained on the gamma camera. Copyright (1999) Blackwell Science Pty Ltd

1999-11-01

22

Ageing and the environment: the effects of early nutrition and reproductive effort on senescence in birds.  

Environmental Research Database

DescriptionThe overall aim of this application is to examine experimentally environmental influences on the pattern of senescence in birds. We plan to experimentally uncouple chronological age and reproductive effort and examine their effects on reproductive performance and lifespan. We also plan to examine experimentally how these relationships are influenced by nutritional conditions during early development. We will combine the organismal fitness measures of lifespan and reproductive performance with me [continued...

2005-01-30

23

Effect of heat treatment on tensile properties and fracture toughness of two-phase #alpha#+#beta# titanium alloy Ti-6Al-2Mo-2Cr  

International Nuclear Information System (INIS)

In the paper results of the investigation on the effect of microstructure on room temperature tensile properties and fracture toughness of two-phase #alpha#+#beta# titanium alloy Ti-6Al-2Mo-2Cr have been presented. Microstructure has been varied by changes in the cooling rate from the solution treatment temperature and aging time and temperature. Mechanical properties examined show dependence on the treatment conditions, especially aging conditions. It has been attributed mainly to the amount and morphology of #alpha# phase obtained after heat treatment. The higher volume fraction of lamellar #alpha# structure, the higher fracture toughness. (author)

1998-05-17

24

Low-pH injection grout for deep repositories. Summary report from a co-operation project between NUMO (Japan), Posiva (Finland) and SKB (Sweden)  

Energy Technology Data Exchange (ETDEWEB)

The use of standard cementitious material creates pulses of pH in the magnitude of 12-13 in the leachates and release alkalis. Such a high pH is detrimental and also unnecessarily complicates the safety analysis of the repository. As no reliable pH-plume models exist, the use of products giving a pH below 11 in the leachates facilitates the safety analysis. Also, according to current understanding, the use of low-pH cement (pH = 11) will not disturb the functioning of the bentonite, although limiting the amount of low-pH cement is recommended. A result of the project is that there are both low-pH cementitious material for grouting larger fractures (= 100 {mu}m) and non-cementitious material for grouting smaller fractures (< 100 {mu}m) that will, after further optimisation work, be recommended for grouting of deep repositories. This project concentrated on the technical development of properties for the low pH grouts. Long-term safety and ...

2005-06-01

25

An Ecological Risk Model for Early Childhood Anxiety: The Importance of Early Child Symptoms and Temperament  

Science.gov (United States)

Childhood anxiety is impairing and associated with later emotional disorders. Studying risk factors for child anxiety may allow earlier identification of at-risk children for prevention efforts. This study applied an ecological risk model to address how early childhood anxiety symptoms, child temperament, maternal anxiety and depression symptoms, violence exposure, and sociodemographic risk factors predict school-aged anxiety symptoms. This longitudinal, prospective study was conducted in a representative birth cohort (n = 1109). Structural equation modeling was used to examine hypothesized associations between risk factors measured in toddlerhood/preschool (age = 3.0 years) and anxiety symptoms measured in kindergarten (age = 6.0 years) and second grade (age = 8.0 years). Early child risk factors (anxiety symptoms and temperament) emerged as the most robust ...

2011-05-01

26

Complex radiation degradation behaviour of PVC materials under accelerated aging conditions  

International Nuclear Information System (INIS)

The radiation degradation behavior of three commercial polyvinyl chloride (PVC) materials has been investigated. All three exhibit an interesting reversal in the trend of the tensile strength part way through the aging experiment: the tensile strength first drops, then rises. The early drop is associated with oxidative scission; the rise is associated with crosslinking and is preceded by the material reaching the gel point. It was also found that the tensile elongation tended to level out in advanced stages of aging with the levelling-out values dependent on the dose rate. These phenomena pose complications for the design of accelerated aging tests. (author).

1982-10-01

27

Complex radiation degradation behavior of PVC materials under accelerated aging conditions  

Energy Technology Data Exchange (ETDEWEB)

The radiation degradation behavior of three commercial polyvinyl chloride (PVC) materials has been investigated. All three exhibit an interesting reversal in the trend of the tensile strength part way through the aging experiment: the tensile strength first drops, then rises. The early drop is associated with oxidative scission; the rise is associated with crosslinking and is preceded by the material reaching the gel point. It was also found that the tensile elongation tended to level out in advanced stages of aging with the leveling-out values dependent on the dose rate. These phenomena pose complications for the design of accelerated aging tests.

1983-07-01

28

Femoral head vitality after intracapsular hip fracture  

International Nuclear Information System (INIS)

Femoral head vitality before, during and at various intervals from the operation was determined by tetracycline labeling and/or _9_9 sp (m)Tc-MDP scintimetry. In a three-year follow-up, healing prognosis could be determined by scintimetry 3 weeks from operation; deficient femoral head vitality predicting healing complications and retained vitality predicting uncomplicated healing. A comparison between pre- and postoperative scintimetry indicated that further impairment of the femoral head vitality could be caused by the operative procedure, and as tetracycline labeling prior to and after fracture reduction in 370 fractures proved equivalent, it was concluded that the procedure of osteosynthesis probably was responsible for capsular vessel injury, using a four-flanged nail. The four-flanged nail was compared with a low-traumatic method of osteosynthesis, two hook-pins, in a prospective randomized 14 month study, and the postoperative femoral ...

2010-06-01

29

The influence of inclusion spacing and microstructure on the fracture toughness of the secondary hardening steel AF1410  

Energy Technology Data Exchange (ETDEWEB)

An approach to the ductile fracture of ultra high strength steels has been evaluated. According to this approach the critical crack tip opening, delta/sub IC/, will scale with X/sub 0/(R/sub V//R/sub I/vertical bar/sub R//sub 0/. X/sub 0/ is an average inclusion spacing and (R/sub V/R/sub I/)vertical bar/sub R//sub 0/ is the void radius divided by the radius of the inclusion nucleating the void evaluated at the average inclusion size. AF1410 was selected to test this approach because it has exceptionally high fracture toughness on aging at 510/sup 0/C and because its toughness varies markedly with aging temperature. The results from this and earlier work showed a linear relationship exists between delta/sub IC/ and X/sub 0/(R/sub V//R/sub I/)vertical bar /sub R//sub 0/ for values of delta/sub IC/ ranging from about 8 ..mu..m to 60 ..mu..m. The values of (R/sub V//R/sub I/)vertical bar /sub R//sub 0/ for ...

1987-07-01

30

Osteocyte death and hip fracture.  

Science.gov (United States)

The viability of osteocytes can be demonstrated in sawn decalcified sections of bone by their lactate dehydrogenase activity. In the cancellous bone of the femoral head, the proportion of lacunae containing viable osteocytes decreased from 88 +/- 7% (mean +/- SD) at 10-29 years to 58 +/- 12% (P Ultimate compressive strength did not correlate with osteocyte viability. In the femoral head there is gradual, age-related reduction in osteocyte viability that can be more pronounced in hip fracture. Osteocyte death may affect bone quality by impairing repair of fatigue damage. PMID:8275364

1993-01-01

31

Humeral cortical thickness in female Bantu - its relationship to the incidence of femoral neck fracture  

International Nuclear Information System (INIS)

Measurements of the humeral cortical thickness demonstrate that generalised osteoporosis in female Bantu commences in the fifth decade and gradually increases until, in the ninth decade, all subjects are osteoporotic. The combined cortical thickness (CCT) of the humerus in young adults is very similar to that found previously in a white London population and the loss of cortex with age is very similar. It is concluded that the known low incidence of femoral neck fracture in Bantu is not due to a lower incidence of generalised osteoporosis but to environmental factors. The chief environmental factor postulated is the greater amount of physical work performed by the Bantu. A more careful mode of walking is suggested as a subsidiary cause. (orig.).

32

Switchgrass ultimate stresses at typical biomass conditions available for processing  

Energy Technology Data Exchange (ETDEWEB)

Biomass tensile and shear ultimate failure stresses were measured with the aim of identifying biomass 'weakest mode of failure' or 'natural fracture point' as a basis for future grinder designs. Switchgrass (Panicum virgatum L.) ultimate stresses were determined for Alamo and Kanlow varieties over ranges in maturity and moisture content. Alamo had greater ultimate tensile stress than Kanlow (P=0.0091), with mean values of 97.8 and 89.7MPa, respectively. Alamo had greater ultimate shear stress than Kanlow (P=0.0091), with mean values of 20.5 and 17.9MPa, respectively. Shear was the 'weakest mode of failure'. Grinders that use knives, shear bars, and mechanical pinch points that apply opposed-sliding actions are expected to be more energy efficient. Mean ultimate tensile stress and shear stress were significantly different between switchgrass varieties. A survey of failure stresses for a range of biomass ...

2006-03-15

33

Putative Biomarkers and Targets of Estrogen Receptor Negative Human Breast Cancer  

UK PubMed Central (United Kingdom)

Breast cancer is a progressive and potentially fatal disease that affects women of all ages. Like all progressive diseases, early and reliable diagnosis is the key for successful treatment and annihilation....Full Text Available

34

PKU is a reversible neurodegenerative process within the nigrostriatum that begins as early as 4 weeks of age in Pahenu2 mice  

UK PubMed Central (United Kingdom)

Phenylketonuria (PKU) is a common genetic disorder in humans that arises from deficient activity of phenylalanine hydroxylase (PAH), which catalyzes the conversion of phenylalanine to tyrosine....Full Text Available

2007-01-05

35

Impaired Perinatal Growth and Longevity: A Life History Perspective  

UK PubMed Central (United Kingdom)

Life history theory proposes that early-life cues induce highly integrated responses in traits associated with energy partitioning, maturation, reproduction, and aging such that the individual phenotype...Full Text Available

2009-01-01

36

If started early in life, metformin treatment increases life span and postpones tumors in female SHR mice  

UK PubMed Central (United Kingdom)

Hyperglycemia and hyperinsulinemia accelerate both aging and cancer. Antidiabetic biguanides such as metformin decrease glucose, insulin and IGF-1 level. Metformin increases lifespan and prevents cancer...Full Text Available

37

Age at the onset of senescence in birds and mammals is predicted by early-life performance  

UK PubMed Central (United Kingdom)

Life-history theory predicts that traits involved in maturity, reproduction and survival correlate along a fast–slow continuum of life histories. Evolutionary theories and empirical results...Full Text Available

2010-09-22

38

The explosion reason analysis of urea reactor of Pingyin  

British Library Electronic Table of Contents (United Kingdom)

In allusion to the explosion of a urea reactor took place in a fertilizer plant at Pingyin, Shandong, China, a series of evidence collection and inspection jobs which includes collecting operation condition and parameters, sampling the explosion fracture, reactor body apart from explosion fracture, and leak detection medium and its hangover, etc., had been carried out firstly. Based on these jobs, farther analysis and computation work has been done to the structural and materials characteristics and the operation condition of the urea reactor, including compositions, metallographic phases, tensile properties, impact energy, strain ageing characteristics, and fracture toughness of the urea reactor steels, the compositions of leak detection medium and its hangover in the urea reactor, and ex...

2009-01-01

39

Early detection by sup(99m)Tc-Sn-pyrophosphate scintigraphy of femoral head necrosis following medial femoral neck fractures  

International Nuclear Information System (INIS)

A selected series of 24 patients with displaced medial femoral neck fracture, treated with closed reduction and osteosynthesis with cancellous bone screws (ASIF), were investigated. During an observation period of 6 to 26 months, serial hip joint scintigraphies were performed and compared with serial X-ray examinations. At the first scintigraphic examination performed on average 5-6 weeks after the fracture, two separate investigators found a decreased amount of activity or no activity in the femoral head of 10 and 8 patients, respectively. At the second scintigraphic examination performed on average 11.1 weeks after the fracture both investigators found no activity or a decreased amount of activity in 8 patients. This figure declined to 7 during the following period, because one patient with decreased activity was recorded as having normal activity 15 months after the fracture. These 7 patients all ...

40

Study of Tibial Shaft Fractures in Children  

Science.gov (United States)

Tibial Shaft Fractures in Children

2010-11-09

41

Early cretaceous age of orthogneiss from the Charleston Metamorphic Group, New Zealand  

International Nuclear Information System (INIS)

Discordant U-Pb zircon isotopic data from amphibolite facies orthogneisses of the Charleston Metamorphic Group, western South Island, New Zealand, define a lower intercept age of 114#+-#18 m.y. that is interpreted as the crystallization age of the orthogneiss magmas. The upper intercept age of 1026#+-#97 m.y. reflects inherited components of Precambrian zircon derived from the source region of the magmas. The age, and whole rock chemical characteristics, indicate that the orthogneisses are part of the same phase of Early cretaceous magmatic activity that produced voluminous arc-related calc-alkaline plutonic rocks throughout western South Island. Previously published K-Ar and Rb-Sr mineral ages indicate uplift and cooling of the Charleston Metamorphic Group to less than 400deg C by 110-90 m.y. This uplift occurred as a consequence of low-angle normal faulting ...

42

Modeling jet penetration in glass  

Energy Technology Data Exchange (ETDEWEB)

It is well known that composite armors, consisting of glass elements confined with metallic tampers, are extraordinarily effective against shaped charge attack. Early experiments showed that jets fired against glass targets appeared to be bombarded by tiny fragments that destroyed alignment and reduced residual jet penetration. This result was attributed to an elastic rebound effect in which the outward radial motion of the target around the jet periphery was supposed to be arrested by tensile hoop stresses which developed behind the divergent shock front. Glass fragments were then accelerated radially inward and these destabilized the jet. To sustain the large tensile hoop stresses required, the glass must not have been fractured by the initial shock, behind which the stress state is typically well above the Hugoniot elastic limit. Modeling the penetration of a jet into glass requires not only determining the spall strength, i.e., the tensile ...

1990-04-05

43

Focus on O & M  

Energy Technology Data Exchange (ETDEWEB)

A series of short articles discusses: use of a chemically bonded ceramic composite liner, WellerDensit, to protect the steel surface of pulverizer classifier cones; use of a fused cast basalt liners developed by Abresist Corp. in pipes for transporting coal and ash; a survey completed by the National Energy Technology Laboratory to identify causes of outages and other concerns expressed by PC and FBC boiler operators; and Temp-Age, Early Visc-Age and Modern Visc-Age systems for controlling the viscosity of heavy fuel oil to maintain proper combustion. 7 figs.

2004-10-01

44

Study of osteoporosis using dual energy X-ray absorptiometry  

Energy Technology Data Exchange (ETDEWEB)

Dual energy X-ray absorptiometry (Hologic QDR-1000) was used to quantitatively analyze the diagnosis and prevention of osteoporosis. The peak bone mineral density (BMD) of the spine appeared in normal men in their twenties and in normal women in their thirties. There was acceleration of bone loss in the 50 to 60 year age bracket (premenopause and postmenopause) in normal women. On the contrary, the peak BMD of the femoral neck in normal men and women appeared in their twenties after which it decreased slightly with age. Comparison showed that the femoral neck BMD of normal women was lower than that of men throughout all ages. The fracture threshold, 0.756 g/cm[sup 2] for the spine, was obtained by scanning 73 females with spinal fractures, the mean BMDs for L2-L4 at the 90th percentile level were used as the fracture threshold. The fracture ...

1992-04-01

45

Strength of VT22 titanium alloy in various structural states  

International Nuclear Information System (INIS)

The influence of heat treatment on the structure, mechanical properties and fracture peculiarities of high-strength (#alpha#+#beta#)-titanium alloy VT22 has been studied. It is ascertained that thermal cycling and subsequent high-temperature aging permit to reduce considerably crack growth rate. Thermal cycling is realized in the following mode: heating in #beta#-region, cooling and allowance in (#alpha#+#beta#)-region, heating in #beta#-region.

46

Microstructure and crack propagation in Ti-3Al-8V-6Cr-4Mo-4Zr  

International Nuclear Information System (INIS)

Fatigue-crack growth in air and in aqueous 3.5-percent NaCl as well as fracture toughness are evaluated for the metastable beta-titanium alloy Ti-3Al-8V-6Cr-4Mo-4Zr in various microstructural conditions. Two solution heat treatments (SHT), 800 C and 927 C, were chosen to produce two different grain sizes. Approximately 20 vol pct unrecrystallized beta grains remained after SHT at the lower temperature. Yield stresses were 895 and 850 MPa, respectively. Both simplex and duplex aging treatments were performed for both grain sizes to vary the distribution of alpha precipitates while keeping the yield stress in the range of 1075-1220 MPa for all aged conditions. Unaged material exhibits significantly higher fracture toughness levels than aged material. The unrecrystallized regions were associated with a loss in ductility and toughness. 21 refs.

1990-10-07

47

Studies on scintigraphic findings after femoral head replacement  

Energy Technology Data Exchange (ETDEWEB)

Femoral head replacement was performed for femoral neck fracture or femoral head necrosis on 36 hips of 34 patients on whom Tc-99m MDP scintigraphy was done for analysis of radioisotope uptake around the prosthesis. In the cases with satisfactory clinical course after replacement surgery the uptake was high in the area between the prosthesis and the trochanter, in the area of the stem tip of the prosthesis and in the acetabular area. The high uptake decreased gradually and reached a normal level by 8 months after surgery. The cases with no decrease of high uptake by 8 months after surgery were considered to have had an eventful postoperative course associated with some complication such as infection, fracture, loosening etc. Tc-99m MDP scintigraphy was useful for early detection of complications and to evaluate progress of the operated patients. (author)

2001-03-01

48

Ewing's sarcoma recurrence vs radiation necrosis in dynamic contrast-enhanced MR imaging: a case report  

International Nuclear Information System (INIS)

Purpose. We report a case of Ewing's sarcoma in the right distal femur in a 6-year-old male to demonstrate how dynamic contrast-enhanced magnetic resonance imaging (DEMRI) findings predicted histopathology. Materials and methods. DEMRI was performed at presentation and during and after completion of chemotherapy and radiation therapy. Histopathologic studies were done at presentation, at 77 weeks (20 weeks after a pathological fracture), and from the en bloc resection at 104 weeks. Results. DEMRI predicted the early tumor response, absence of tumor recurrence, presence of necrosis and lack of fracture healing, confirmed by histopathology. Conclusion. DEMRI is a clinically useful tool in managing Ewing's sarcoma. (orig.)

1999-04-01

49

Mechanical properties of Fe -10Ni -7Mn martensitic steel subjected to severe plastic deformation via cold rolling and wire drawing  

Energy Technology Data Exchange (ETDEWEB)

Fe-Ni-Mn martensitic steels are one of the major groups of ultra-high strength steels that have good mechanical properties and ductility in as annealed condition but they suffer from severe inter-granular embitterment after aging. In this paper, the effect of heavy shaped cold rolling and wire drawing on the mechanical properties of Fe-Ni-Mn steel was investigated. This process could provide a large strain deformation in this alloy. The total strain was {epsilon} {approx}7. Aging behavior and tensile properties of Fe-10Ni-7Mn were studied after aging at 753 K. The results showed that the ultimate tensile strength and ductility after cold rolling, wire drawing and aging increased up to 2540 MPa and 7.1 %, respectively, while the conventional steels show a premature fracture stress of 830 MPa with about zero ductility after aging.

2010-07-01

50

Mechanical properties of Fe -10Ni -7Mn martensitic steel subjected to severe plastic deformation via cold rolling and wire drawing  

International Nuclear Information System (INIS)

Fe-Ni-Mn martensitic steels are one of the major groups of ultra-high strength steels that have good mechanical properties and ductility in as annealed condition but they suffer from severe inter-granular embitterment after aging. In this paper, the effect of heavy shaped cold rolling and wire drawing on the mechanical properties of Fe-Ni-Mn steel was investigated. This process could provide a large strain deformation in this alloy. The total strain was #epsilon# #approx#7. Aging behavior and tensile properties of Fe-10Ni-7Mn were studied after aging at 753 K. The results showed that the ultimate tensile strength and ductility after cold rolling, wire drawing and aging increased up to 2540 MPa and 7.1 %, respectively, while the conventional steels show a premature fracture stress of 830 MPa with about zero ductility after aging.

2010-07-01

51

Evaluation of bone mineral content using Quantitative Computed Tomography  

International Nuclear Information System (INIS)

The authors have evaluated bone mineral content in the vertebral spongiosa by means of Computed Tomography. The method proposed by Genant and Cann [17, 18] has been applied to examine 164 healthy volunteers and 108 patients. Both healthy males and females showed a progressive bone mineral loss increasing with age; the bone mineral loss was most severe in females during the 4th and 5th decade of life. Pathology included patients with osteoporotic fractures (vertebral and femural neck), patients with partial gastrectomy, renal failure, primary hyperparathyroidism, Cushing syndrome, corticosteroid therapy. Bone mineral values were significantly lower in most pathologic groups. Computed Tomography proves thus to be a valuable method to assess bone mineral content and to identify patients at risk for fractures.

1988-01-01

52

Estimating personal costs incurred by a woman participating in mammography screening in the National Breast and Cervical Cancer Early Detection Program  

British Library Electronic Table of Contents (United Kingdom)

BACKGROUND.The National Breast and Cervical Cancer Early Detection Program (NBCCEDP) covers the direct clinical costs of breast and cervical cancer screening and diagnostic follow-up for medically underserved, low-income women. Personal costs are not covered. In this report, the authors estimated personal costs per woman participating in NBCCEDP mammography screening by race/ethnicity and also estimated lifetime personal costs (ages 50-74 years).METHODS.A decision analysis model was constructed and parameterized by using empiric data from a retrospective cohort survey of mammography rescreening among women ages 50 years to 64 years who participated in the NBCCEDP. Data from 1870 women were collected from 1999 to 2000. The model simulated the flow of resources incurred by a woman participat...

2008-01-01

53

A calf for all seasons? The potential of stable isotope analysis to investigate prehistoric husbandry practices  

British Library Electronic Table of Contents (United Kingdom)

The Early Bronze Age barrows at Irthlingborough and Gayhurst in central England are notable for the large number of cattle (Bos taurus) remains associated with their human Beaker burials. Previous work using strontium isotope analysis has indicated that most of the cattle analysed, and one aurochs (Bos primigenius), were of local origin [Towers, J., Montgomery, J., Evans, J., Jay, M., Parker Pearson, M., 2010. An investigation of the origins of cattle and aurochs deposited in the Early Bronze Age barrows at Gayhurst and Irthlingborough. Journal of Archaeological Science 37, 508-515.]. In this study, stable isotope analysis of enamel and bone was carried out to investigate whether the mature cattle had experienced similar husbandry practices, climate and environment. Bulk carbon, nitrogen a...

2011-01-01

54

Open-pit explosives  

Energy Technology Data Exchange (ETDEWEB)

This paper explains how mine operators are taking a closer look at the power of explosives and how primary breakage affects other open-pit mining costs. Slurries have overcome most of the disadvantages attributed to them in their early years and may replace Anfo. Effective blasting is the key to an efficient, low-cost mining operation. Reviews are presented on research in crater studies, computer-aided design, the expanding gas theory, and high-speed motion picture cameras that show the importance of shock energy in fracturing the rock interfaces throughout the burden. The paper concludes with MSHA-approved courses in blasting offered throughout the US.

1982-07-01

55

Bone scanning after muscle-pedicle bone graft for femoral neck fracture, (1). Preliminary report  

Energy Technology Data Exchange (ETDEWEB)

sup(99m)Tc-MDP bone scintigraphy was performed on patients who received muscle-pedicle bone graft. In each of the bone head and the bone graft, a time-activity curve was obtained. In this muscle-pedicle bone graft, active revascularization and marked osteogenesis, which suggested rapid bone repairing, were observed. The bone scintigraphy was considered to be useful in observing the result of bone grafts, blood circulation, and time of bone fusion, and of value for early detection of secondary changes.

1982-04-01

56

Early detection of damage and analysis of damage development in metal structural components. Schaedigungsfrueherkennung und Schadensablauf bei metallischen Bauteilen  

Energy Technology Data Exchange (ETDEWEB)

The topics of these short lectures on the subject of cyclic stress were: Microstructural mechanisms of damage accumulation under a multistage cyclic stress until incipient cracking; influence of surface decarbonizing phenomena on the failure behaviour of steel construction parts subjected to cyclic stress; thermocyclic fatigue of pipe samples of austenitic steel 1.4436; studies on surface structuring, microstructure and fatigue in LCF area. The short lectures on effects of quasi-static and creep stress were: Shear fracture in AlMg alloys as a result of local plastic instability; study of formation and growth of pores for an early recognition of damage and the course of damage in heat-resistant steels under creep test; experimental and numeric studies of the infuence of the microstructure on the course of damage during shear fractures of steel; numerical modelling of ductile fractures on the basis of ...

1989-01-01

57

Serum Osteocalcin/Bone-Specific Alkaline Phosphatase Ratio Is a Predictor for the Presence of Vertebral Fractures in Men with Type 2 Diabetes  

British Library Electronic Table of Contents (United Kingdom)

We examined whether or not BMD or bone markers were useful for assessing the risk of vertebral fractures in 248 Japanese men with type 2 diabetes. We analyzed the relationships between bone markers (osteocalcin [OC], bone-specific alkaline phosphatase [BAP], urinary N-terminal cross-linked telopeptide of type-I collagen) or BMD and HbA1c, urinary C-peptide, insulin-like growth factor-I (IGF-I), parathyroid hormone, 1,25(OH)2 vitamin D, and the presence of prevalent vertebral fractures. Multiple regression analysis adjusted for age, body height, weight, duration of diabetes, and serum creatinine showed that serum OC and OC/BAP ratio were correlated negatively with HbA1c (P?P?P?

2009-01-01

58

Effect of fatiguing exercise on longitudinal bone strain as related to stress fracture in humans.  

Science.gov (United States)

Muscular fatigue in the training athlete or military recruit has been hypothesized to cause increased bone strain that may contribute to the development of a stress fracture. Under normal circumstances, muscles exert a protective effect by contracting to reduce bending strains on cortical bone surfaces. In vivo strain studies in dogs show that muscle fatigue following strenuous exercise elevates bone strain and changes strain distribution. However, a similar experiment has yet to be performed in humans. The purpose of this work was to test the hypothesis in humans that strenuous fatiguing exercise causes an elevation in bone strain. It was also hypothesized that this elevation is greater in younger people than in older people due to the decline in muscle strength and endurance that normally occurs with age. To test these hypotheses, strain in the tibiae of seven human volunteers was measured during walking before and after a period of fatiguing ...

59

Early spondyloarthropathy: scintigraphic, biological, and clinical findings in MRI-positive patients  

British Library Electronic Table of Contents (United Kingdom)

There are no specific diagnostic tests or a gold standard method for measuring disease activity and outcome in spondyloarthropathies (SpA). Many different methods have been developed to assess the signs and symptoms in SpA. The aim of this study was to evaluate the value of scintigraphy, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and Bath Ankilosing Spondylitis Disease Activity Index (BASDAI) in the evaluation of disease activity in early axial SpA diagnosed with magnetic resonance imaging (MRI). Thirty early MRI-positive axial SpA patients (23 males, 7 females) with a median age of 35 (18?55) years and a median duration of inflammatory low back pain of 24 (8?60) months were included in the study. In the patients with sacroiliitis, the sensitivity, specificity, and pos...

2008-01-01

60

Thermal aging of cast stainless steels in LWR systems: Estimation of mechanical properties  

Energy Technology Data Exchange (ETDEWEB)

A procedure and correlations are presented for predicting Charpy-impact energy, tensile flow stress, fracture toughness J-R curve, and J{sub IC} of aged cast stainless steels from known material information. The ``saturation`` impact strength and fracture toughness of a specific cast stainless steel, i.e., the minimum value that would be achieved for the material after long-term service, is estimated from the chemical composition of the steel. Mechanical properties as a function of time and temperature of reactor service are estimated from impact energy and flow stress of the unaged material and the kinetics of embrittlement, which are also determined from chemical composition. The J{sub IC} values are determined from the estimated J-R curve and flow stress. Examples of estimating mechanical properties of cast stainless steel components during reactor service are presented. A common ``lower-bound`` J-R curve for cast ...

1991-11-01

61

A personal computer based system to evaluate J-integral by a single specimen unloading compliance method: Pt. 2  

International Nuclear Information System (INIS)

A personal computer based single specimen unloading technique has been demonstrated using a nuclear grade pressure vessel material, A533B Class I steel, and an #alpha#-#beta# titanium alloy, CORONA-5. Experimental parameters investigated in the case of steel include the effect of test temperature, loading rate and neutron irradiation. Results revealed the effect of dynamic strain aging (DSA) as a drop in the critical crack initiation fracture toughness (Jsub(q)); the minimum in Jsub(q) shifts to higher temperatures at higher test speeds as predicted from DSA models. In CORONA-5, the effects of microstructure and heat treatment for two different sizes of equiaxed #alpha# morphology in a #beta#-matrix heat treated to different yield strengths were investigated. It is found that the observed higher values of Jsub(q) and tearing modulus result from a greater tortuosity of the crack path and ease of crack blunting. The largest increase in Jsub(q) ...

63

Uranium-lead zircon ages from the Median Tectonic Zone, New Zealand  

International Nuclear Information System (INIS)

The Median Tectonic Zone (MTZ) of New Zealand is a generally north trending belt of Mesozoic subduction related I-type plutonic, volcanic, and sedimentary rocks in South Island and Stewart Island that separates Permian strata of the Eastern Province Brook Street Terrane from lower to mid Gondwana margin assemblages of the Western Province. High precision isotope dilution U/Pb ages of zircons from 30 rocks are reported. Pre-digestion leaching of zircon in hydrofluoric acid yielded significantly more concordant residues by removing common Pb and dissolving more soluble high-U domains that have been more affected by relatively recent Pb loss. The results show that MTZ magmatism ranges in age from at least Early Triassic to Early Cretaceous (247-131 Ma), with a pronounced gap in the Middle Jurassic. Triassic plutons tend to occur on the eastern side of the MTZ, and they intrude volcanic/sedimentary ...

64

Processing and properties of novel high strength {gamma}-TiAl  

Energy Technology Data Exchange (ETDEWEB)

Extrusion and subsequent heat treatment of the alloys investigated can lead to reasonable room temperature ductilities and very high strengths being developed compared to the cast + HlPed material. In Ti-45Al-10Nb reasonably room temperature fracture toughness was developed which did not depend on extrusion temperature. For the alloy Ti-48Al-2Cr-0.2C a previously developed solution and ageing heat treatment did not increase the high temperature strength properties when compared to the 'annealed' condition. (orig.)

2000-07-01

65

Optimising post-weld heat treatment for alloy 800/(9Cr-1Mo) steel joints using toughness parameters from tensile tests  

Energy Technology Data Exchange (ETDEWEB)

Proposed ductile fracture toughness parameters from tensile tests have been successfully used to determine the post-weld heat treatment temperature for an alloy 800/(9Cr-1Mo) steel dissimilar metal weld joint that is optimum with respect to accelerated aging, which simulates service conditions. This approach proved superior to using microstructural analysis, microhardness profiles, and conventional tensile properties. (author).

1997-04-01

66

Effect of #alpha#-phase morphology and distribution on the tensile ductility of a metastable beta titanium alloy  

International Nuclear Information System (INIS)

In a program to develop a metastable beta alloy with improved fracture toughness, it was found that the tensile ductility of the alloy Ti-8 Mo-4.5 Cr-2.5 Al was strongly dependent on both processing history and annealing temperature. Evaluation of the microfracture mode of tensile samples by scanning electron microscope and metallographic techniques showed that the presence of a continuous grain boundary alpha is the most significant parameter controlling the ductility and is highly detrimental. It is concluded that, for optimum processing, the material must be worked prior to aging to avoid this grain boundary phase.

67

The quest to beat aging  

CERN Document Server

The quest to beat aging

2000-01-01

68

The industrial application of fracture mechanics concepts discussed at the background of international standards and guidelines; Die industrielle Anwendung bruchmechanischer Konzepte vor dem Hintergrund internationaler Bewertungsvorschriften und Regelwerke  

Energy Technology Data Exchange (ETDEWEB)

Many features from the background for an intensified application of fracture mechanics concepts in many industries world-wide. These include requirements for a permanent increase of the level of performance of technical components and structures by the introduction of new materials, joining technologies and design principles, the problem of ageing components and life extension, an increased emphasis on non-destructive in-service inspection combined with improved NDT techniques, and also a number of failure events caused by fatigue and fracture The aim of the present paper is to give a brief state-of-the-art review on how fracture mechanics is applied in different industrial branches today. This is based on standards and guidelines in the aerospace industry, in the nuclear and fossil power generation, in the chemical and petrochemical and the pipeline industry, in civil engineering, offshore technique ...

2000-07-01

69

Aging, tumor suppression and cancer: High-wire act!  

Energy Technology Data Exchange (ETDEWEB)

Evolutionary theory holds that aging is a consequence of the declining force of natural selection with age. We discuss here the evidence that among the causes of aging in complex multicellular organisms, such as mammals, is the antagonistically pleiotropic effects of the cellular responses that protect the organism from cancer. Cancer is relatively rare in young mammals, owing in large measure to the activity of tumor suppressor mechanisms. These mechanisms either protect the genome from damage and/or mutations, or they elicit cellular responses--apoptosis or senescence--that eliminate or prevent the proliferation of somatic cells at risk for neoplastic transformation.We focus here on the senescence response, reviewing its causes, regulation and effects. In addition, we describe recent data that support the idea that both senescence and apoptosis may indeed be the double-edged swords predicted by the evolutionary hypothesis ...

2004-08-15

70

Effect of V and W addition on the high temperature strength properties of 12%Cr-15%Mn austenitic steels. 12%Cr-15%Mn austenite ko no ondo kyodo ni oyobosu V to W tenka no eikyo  

Energy Technology Data Exchange (ETDEWEB)

Experimental discussions were given on effect of V and W addition on the high temperature strength properties of 12% Cr-15% Mn austenite steels. The test samples were added with W at 0% to 3.5% and V at 0% to 0.5% in addition to C and N, and were given aging treatment or solution treatment. This paper describes the following matters on the results of high-temperature strength measurements and structural observation: A remarkable trend was observed that M23 Cb type carbides precipitate in the aging treatment, wherein aging hardening appears prominently which is attributable to ultra-fine deposits of vanadium nitride (VN) in the V-added material; the V addition is very effective in increasing the high-temperature tensile strength and creep fracture strength as compared with single W addition, wherein the said carbides that accelerate the precipitation as a result of the V addition make a large ...

1992-11-01

71

Quantitative assessment of bone scintigraphy in the hip joint disease  

International Nuclear Information System (INIS)

Quantitative assessment of bone scintigraphy was performed in fifty-six patients with hip joint disease including femoral neck fracture, aseptic necrosis of the femoral head, traumatic dislocation of the hip, Perthes disease, and transient synovitis of the hip. In the static study, bone scintigraphy was obtained 3 hours after injection of sup(99m)Tc-MDP by gamma camera equipped with a computer and uptake ratios were calculated. In the dynamic study, bone scintigraphy was performed in one, 3 and 5 hours after injection of radionuclide. Femoral head uptake ratio was markedly decreased in osteonecrosis following femoral neck fracture and characteristically increased in aseptic necrosis of the femoral head but prolonged retention of sup(99m)Tc-MDP could be observed. Uptake ratios of epiphysis were decreased in Perthes disease but normal in transient synovitis of the hip. Static and dynamic study of bone scintigraphy may be useful for ...

72

Two-year diagnostic stability in early-onset first-episode psychosis  

British Library Electronic Table of Contents (United Kingdom)

Background:- Only one study has used a prospective method to analyze the diagnostic stability of first psychotic episodes in children and adolescents. The Child and Adolescent First-Episode Psychosis Study (CAFEPS) is a 2-year, prospective longitudinal study of early-onset first episodes of psychosis (EO-FEP). Aim:- To describe diagnostic stability and the variables related to diagnostic changes. Methods:- Participants were 83 patients (aged 9-17-years) with an EO-FEP consecutively attended. They were assessed with a structured interview (Kiddie-Schedule for Affective Disorders and Schizophrenia, Present and Lifetime version) and clinical scales at baseline and after 2-years. Results:- The global consistency for all diagnoses was 63.9%. The small group of bipolar disorder had high stabilit...

2011-01-01

73

Cochrane Review: Polysaccharide vaccines for preventing serogroup A meningococcal meningitis  

British Library Electronic Table of Contents (United Kingdom)

AbstractBackground Randomised controlled trials (RCTs) in the 1970s and early 1980s showed the polysaccharide serogroup A vaccine (SgAV) prevented serogroup A meningococcal meningitis (SGAMM). Subsequent non-RCTs suggested significant variations in the age-specific duration of protection among children. Objectives To determine the protective effect, duration of protection, age-specific effects and the effect of booster doses in children of the SgAV against SGAMM. Search strategy We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2010, issue 2) which contains the Acute Respiratory Infections Group's Specialised Register, MEDLINE (January 1950 to May Week 3, 2010) and EMBASE (January 1974 to May 2010). Selection criteria We included RCTs. Non-RCTs ...

2011-01-01

74

The Assessment of Fracture Risk  

UK PubMed Central (United Kingdom)

Bone mineral density is considered to be the standard measure for the diagnosis of osteoporosis and the assessment of fracture risk. The majority of fragility fractures occur in patients with bone mineral...Full Text Available

2010-03-01

75

DISCUSSION ON SPINAL INJURIES  

UK PubMed Central (United Kingdom)

(1).—Varieties of spinal injuries, the three groups of common usage: fractures, dislocations, fracture-dislocations. Shall not refer in detail to fractures of the spinous or transverse processes....Full Text Available

1928-02-01

76

Research activities of MPA, Stuttgart University, for enhanced safety and reliability of components under complex load; Forschungsaktivitaeten der MPA Universitaet Stuttgart zu Erhoehung der Sicherheit und Zuverlaessigkeit komplex beanspruchter Bauteile  

Energy Technology Data Exchange (ETDEWEB)

MPA research activities focus on fracture prevention and on the development of a generally applicable method of component integrity testing which, independent of the safety relevance of the components involved, is also part of ageing management. (orig.) [German] Die Forschungsaktivitaeten an der MPA im Hinblick auf die Erhoehung der Sicherheit und Zuverlaessigkeit komplex beanspruchter Bauteile orientieren sich an den Grundgedanken des Basissicherheitskonzepts (Prinzip des Bruchausschlusses). Zielsetzung war dabei die Entwicklung eines allgemein anwendbaren Nachweisverfahrens zur Komponentenintegritaet, das, abhaengig von der sicherheitstechnischen Relevanz der zu betrachtenden Komponenten, auch Bestandteil des Alterungsmanagements ist. (orig.)

2004-07-01

77

Noninvasive prediction of vertebral body compressive strength using nonlinear finite element method and an image based technique  

British Library Electronic Table of Contents (United Kingdom)

Noninvasive prediction of vertebral body strength under compressive loading condition is a valuable tool for the assessment of clinical fractures. This paper presents an effective specimen-specific approach for noninvasive prediction of human vertebral strength using a nonlinear finite element (FE) model and an image based parameter based on the quantitative computed tomography (QCT). Nine thoracolumbar vertebrae excised from three cadavers with an average age of 42 years old were used as the samples. The samples were scanned using the QCT. Then, a segmentation technique was performed on each QCT sectional image. The segmented images were then converted into three-dimensional FE models for linear and nonlinear analyses. A new material model was implemented in our nonlinear model being more...

2010-01-01

78

Geothermal resource assessment of Idaho Springs, Colorado. Resource series 16  

Energy Technology Data Exchange (ETDEWEB)

Located in the Front Range of the Rocky Mountains approximately 30 miles west of Denver, in the community of Idaho Springs, are a series of thermal springs and wells. The temperature of these waters ranges from a low of 68/sup 0/F (20/sup 0/C) to a high of 127/sup 0/F (53/sup 0/C). To define the hydrothermal conditions of the Idaho Springs region in 1980, an investigation consisting of electrical geophysical surveys, soil mercury geochemical surveys, and reconnaissance geological and hydrogeological investigations was made. Due to topographic and cultural restrictions, the investigation was limited to the immediate area surrounding the thermal springs at the Indian Springs Resort. The bedrock of the region is faulted and fractured metamorphosed Precambrian gneisses and schists, locally intruded by Tertiary age plutons and dikes. The investigation showed that the thermal waters most likely are fault controlled and the thermal area does not have ...

1982-01-01

79

Magnetic resonance imaging: early detection of central nervous system involvement in acquired immunodeficiency syndrome (AIDS)  

International Nuclear Information System (INIS)

Central Nervous System (CNS) involvement, whether primary by the Human Immunodeficiency Virus - HIV - itself, or secondary (toxoplasmosis or lymphoma) is remarkably frequent in AIDS, in 40 to 70% of cases, depending upon the author. In order to study the natural history of this illness, a cohort of 25 asymptomatic seropositive patients have been established. Every 6 months these patients undergo biological and clinical examinations, as well as Magnetic Resonance brain scans. After two examinations at a 6 month's interval, the first results are reported. Out of these 25 cases, 9 present anomalies: One patient with diffuse cerebral atrophy and 8 others with high signal intensity areas on T2 weighted sequences, like those of the Multiple Sclerosis. No relationship could be demonstrated between the existence of these lesions and various criteria such as age, sex, risk factors and T4 cells count. The nature of these lesions is not lear. They certainly indicate ...

80

Ewing's sarcoma. Evaluation of radiotherapy and control of the primary tumor  

International Nuclear Information System (INIS)

From 1964 to 1973 at the Institute of Oncology and Radiobiology, Havana City, 18 clinical histories were studied, all of them from patients with Erwing's sarcoma, histologically diagnosticated by biopsy. Age, sex, race, traumatism background, hemogram disturbances, radiographic signs, primary tumor localization, and early treatment, were exposed. Early treatment in 14(83%) patients as radiotherapy. Local recurrence or metastasis was presented in 10(55,5%) patients during the two first years following attack treatment. Five (35,7%) patients was the survival rate within five years starting early treatemt. After five years, three (21,4%) patients were alive: for 18 and 14 year, and 64 month period; two patients died at 62 and 64 months. It is concluded that this survival may be increased by initial behaviour enclosed at the technologic therapeutic patterns of the the Institute of Oncology and Radiobiology, ...

82

CT evaluation of acetabular fractures  

International Nuclear Information System (INIS)

The paper deals with sixteen cases of acetabular fractures studied with CT. After a short description of the normal CT findings, the different kind of fractures are reported. The usefulness of CT examination in evaluating acetabular fractures and their complications is confirmed both in conservative treatment and surgical approach.

1986-01-01

83

Application of sequence stratigraphy to carbonate reservoir prediction, Early Palaeozoic eastern Warburton basin, South Australia  

Energy Technology Data Exchange (ETDEWEB)

The Early Palaeozoic Warburton Basin underlies the gas and oil producing Cooper and Eromanga Basins. Postdepositional tectonism created high potential fracture porosities, complicating the stratigraphy and making reservoir prediction difficult. Sequence stratigraphy integrating core, cuttings, well-log, seismic and biostratigraphic data has recognized a carbonate-dominated to mixed carbonate/siliciclastic supersequence comprising several depositional sequences. Biostratigraphy based on trilobites and conodonts ensures reliable well and seismic correlations across structurally complex areas. Lithofacies interpretation indicates sedimentary environments ranging from carbonate inner shelf, peritidal, shelf edge, deep outer shelf and slope to basin. Log facies show gradually upward shallowing trends or abrupt changes indicating possible sequence boundaries. With essential depositional models and sequence analysis from well data, seismic facies ...

1996-12-31

84

Normal development of paranasal sinuses in children: A CT study  

Energy Technology Data Exchange (ETDEWEB)

To evaluate the normal development of the paranasal sinuses in children with CT, authors prospectively studied with brain CT scans of 260 children without known sinus disease, ranging image from 7 days to 16 years. Maximal anteroposterior and transverse diameters(mm) and maximal cross- sectional area(mm{sup 2}) of both sides of the maxillary sinus were measured with the aid of computer device. As to the ethmoidal and spheroidal sinuses, we simply documented the presence of the aplastic ethmoidal sinus and calculated the age-incidence of the spheroidal sinus pneumatization, respectively.There noted three phases in the development of the maxillary sinus. The anteroposterior and transverse diameters of the maxillary sinus increased nearly in parallel. The former was always greater than the latter. In no cases was the edathamil sinus aplastic and almost all sinuses were pneumatized even in infants as early as 7 old days. CT identified the conchal ...

1993-11-15

85

Impingement fracture of the anteromedial tibial margin: a radiographic sign of combined posterolateral complex and posterior cruciate ligament disruption  

Energy Technology Data Exchange (ETDEWEB)

Marginal fractures of the tibial plateau are associated with a high incidence of soft tissue injuries to the stabilising structures of the knee joint. Injuries to the anterior cruciate ligament are associated with the Segond fracture and impingement fractures of the posteromedial tibial plateau. Recognition of these fractures aids diagnosis of these injuries. Marginal fractures of the tibial plateau associated with posterior cruciate ligament injuries are less common, though recently a ''reverse'' Segond fracture has been recognised. We describe a fracture of the anteromedial tibial plateau associated with complete disruption of the posterior cruciate ligament and posterolateral complex. (orig.)

2001-02-01

86

Characteristics of the Mechanical Properties and the Fractures ...  

Science.gov (United States)

... Accession Number : ADA136144. Title : Characteristics of the Mechanical Properties and the Fractures of an Alpha Beta Titanium Alloy,. ...

1983-11-18

87

Development of regional cerebral blood flow during childhood studied with Iodine-123-IMP SPECT  

International Nuclear Information System (INIS)

Regional cerebral blood flow (rCBF) was assessed with single photon emission computed tomography (SPECT), "1"2"3I-N-isopropyl-iodoamphetamine ("1"2"3I-IMP), and the Table-Look-Up method in 51 children (27 boys, 24 girls) considered neurologically normal and aged 1 month to 15 years (mean age, 4 years 1 month; standard deviation (SD) 3 years 11 months) divided into seven age groups. The rCBF was measured in cortical regions, the cerebellum, thalamus, and the head of the caudate nucleus. Curves for reference values and standard deviations were defined for each region. The rCBF rapidly increased until 2 years of age, reaching maximum values during the third to fifth periods (2 to 10 years of age) in each region. The rCBFs then decreased, reaching adult levels at 10 to 15 years of age. The rCBF reached maximum values later in the frontal region than in other ...

2006-06-01

88

Estimation of the age of the universe by the nucleochronology method  

Energy Technology Data Exchange (ETDEWEB)

Unconditional estimates are suggested for the age of radioactive nuclei and hence for the age of the Universe.

1983-10-01

89

FORMATION EPOCHS, STAR FORMATION HISTORIES, AND SIZES OF MASSIVE EARLY-TYPE GALAXIES IN CLUSTER AND FIELD ENVIRONMENTS AT z = 1.2: INSIGHTS FROM THE REST-FRAME ULTRAVIOLET  

International Nuclear Information System (INIS)

We derive stellar masses, ages, and star formation histories (SFHs) of massive early-type galaxies in the z = 1.237 RDCS1252.9-2927 cluster and compare them with those measured in a similarly mass-selected sample of field contemporaries drawn from the Great Observatories Origin Deep Survey South Field. Robust estimates of these parameters are obtained by comparing a large grid of composite stellar population models with 8-9 band photometry in the rest-frame near-ultraviolet, optical, and IR, thus sampling the entire relevant domain of emission of the different stellar populations. Additionally, we present new, deep U-band photometry of both fields, giving access to the critical far-ultraviolet rest frame, in order to empirically constrain the dependence of the most recent star formation processes on the environment. We also analyze the morphological properties of both samples to examine the dependence of their scaling relations on their mass ...

2010-01-20

90

The effect of age hardening on creep crack growth in alloy 800  

International Nuclear Information System (INIS)

The creep crack growth properties of two versions of Alloy 800 have been compared at 500 and 600"0C in the Grade II condition in tests up to 10"4 hours duration. The two alloys were a low carbon alloy containing (wt.%) 0.024 C, 0.5 Ti, 0.3 Al (Alloy B) and a higher carbon alloy containing (wt.%) 0.038 C, 0.2-0.3 Ti, 0.2-3.0 Al (Alloy J). At 600"0C, Alloy B attained maximum age hardening in 10"2 hours, whereas J did not harden significantly in time up to 10"4 hours. Both alloys age hardened at 550"0C with Alloy J hardening more rapidly than B. The creep displacements and displacement rates in small compact tension specimens at 600"0C were smaller than Alloy B than in Alloy J. However, failure times were shorter in Alloy B because of lower displacements for crack initiation and propagation and higher crack growth rates. At 550"0C the displacements for initiation and propagation in Alloy J were smaller than at 600"0C. A consequence of this ...

91

Application of fracture mechanics to cementitious composites  

Energy Technology Data Exchange (ETDEWEB)

This work contains 27 chapters which cover recent advances in fracture mechanics applied to cement-based composites: concrete, reinforced concrete, and fiber reinforced concrete. The book, based on a NATO Advanced Study Institute, is a comprehensive survey of treating nonlinearity associated with crack growth in brittle materials such as cement composites, rocks and ice. The book is divided into 8 major themes: advances in nonlinear fracture mechanics; fracture processes; numerical modelling of fracture; experimental methods of determining fracture parameters; damage and continuum modelling; strain-rate and dynamic effects of crack propagation; stress-corrosion, time and temperature effects on fracture; and implications for concrete structures.

1985-01-01

92

The detection and characterization of natural fractures using P-wave reflection data, multicomponent VSP, borehole image logs and the in-situ stress field determination  

Energy Technology Data Exchange (ETDEWEB)

The objectives of this project are to detect and characterize fractures in a naturally fractured tight gas reservoir, using surface seismic methods, borehole imaging logs, and in-situ stress field data. Further, the project aims to evaluate the various seismic methods as to their effectiveness in characterizing the fractures, and to formulate the optimum employment of the seismic methods as regards fracture characterization.

1995-04-01

93

Intraoperative electron beam therapy and external photon beam therapy with lumpectomy as primary treatment for early breast cancer  

International Nuclear Information System (INIS)

Between 1984 and 1988, seven women with breast cancer were treated with intraoperative electron beam therapy (IOEBT). All patients were Caucasian. Patient age ranged from 37 to 62 (median 53) years. Histopathology was infiltrating duct carcinoma (6/7) or medullary carcinoma (1/7). Four tumors were staged T1 N0 MO, one T1 N1 MO, one T2 N1 MO, and one lesion was recurrent. At the time of primary lumpectomy or axillary node dissection, a dose of 10 or 15 Gy IOEBT was administered to the tumor bed with 6 or 9 MeV electrons through the lumpectomy wound. All patients received 45 or 50 Gy over five to six weeks with 6 MV photons to the breast and, in four patients, to the regional nodes. Three patients received adjuvant chemotherapy and tamoxifen. No post-operative complications were observed. All patients are alive as of August, 1989, with no evidence of recurrent disease. Excellent cosmesis is the rule. Clinical and technical aspects of treatment are presented along ...

94

Computed Tomography in pulmonary cystic fibrosis  

International Nuclear Information System (INIS)

This study was aimed at evaluating CT sensitivity in identifying the signs of pulmonary cystic fibrosis (CF). The chests of 39 patients (16 males and 23 females, mean age 19.1 years) were examined by CT: all patients had been given a clinical score according to Schwachman and Kulckzycki criteria. Thickened bronchial walls were observed in all cases, which are typical of peribronchitis. Bronchiectases were present in 87% of cases; their extent, pattern and localization were exactly shown on CT scans. Bronchoceles were seen on CT scans in 64% of patients; less frequent was the finding of atelectases and subpleural bullous emphysema. In a great number of patients (64% and 82%, respectively) pleural thickening and hilar adenopathy were demonstrated on CT scans. In conclusion, our results confirm CT as a more sensitive method than conventional radiography to identify and locate the signs of pulmonary CF. The early identification of the lesions of ...

1991-01-01

95

{sup 3}H-tetracycline as a proxy for {sup 41}Ca for measuring dietary perturbations of bone resorption  

Energy Technology Data Exchange (ETDEWEB)

Our group is interested in evaluating early effects of dietary interventions on bone loss. Postmenopausal women lose bone following reduction in estrogen which leads to increased risk of fracture. Traditional means of monitoring bone loss and effectiveness of treatments include changes in bone density, which takes 6 months to years to observe effects, and changes in biochemical markers of bone turnover, which are highly variable and lack specificity. Prelabeling bone with {sup 41}Ca and measuring urinary {sup 41}Ca excretion with accelerator mass spectrometry provides a sensitive, specific, and rapid approach to evaluating effectiveness of treatment. To better understand {sup 41}Ca technology as a tool for measuring effective treatments on reducing bone resorption, we perturbed bone resorption by manipulating dietary calcium in rats. We used {sup 3}H-tetracycline ({sup 3}H-TC) as a proxy for {sup 41}Ca and found that a single dose is feasible ...

2007-06-15

96

Matrix diffusion studies by electrical conductivity methods. Comparison between laboratory and in-situ measurements  

Energy Technology Data Exchange (ETDEWEB)

Traditional laboratory diffusion experiments in rock material are time consuming, and quite small samples are generally used. Electrical conductivity measurements, on the other hand, provide a fast means for examining transport properties in rock and allow measurements on larger samples as well. Laboratory measurements using electrical conductivity give results that compare well to those from traditional diffusion experiments. The measurement of the electrical resistivity in the rock surrounding a borehole is a standard method for the detection of water conducting fractures. If these data could be correlated to matrix diffusion properties, in-situ diffusion data from large areas could be obtained. This would be valuable because it would make it possible to obtain data very early in future investigations of potentially suitable sites for a repository. This study compares laboratory electrical conductivity measurements with in-situ resistivity ...

1998-09-01

97

Carbon steel corrosion rates and mechanisms in aqueous nickel chloride at 300C  

International Nuclear Information System (INIS)

Rapid corrosion of PWR steam generator carbon steel support structures and consequential denting of steam generator tubes led to considerable investigation of the mechanism of corrosion and for palliatives. The basic mechanism is now fairly well understood. Chloride present in the boiler feedwater from condenser leakage is concentrated in the support plate crevice as a result of the superheat present. This leads to the formation of a low pH acid ferrous chloride environment either through the hydrolysis of a weak base chloride such as MgCl_2 or the combined action of a neutral chloride with an oxidizing agent. Rapid attack of the carbon steel ensues with the Fe_3O_4 corrosion product forming at the metal/oxide interface. This oxide has a volume approximately twice that of the steel consumed and thus eventually fills the crevice between the tube and the support plate. Oxide growth continues leading to compression of the Alloy 600 primary tube and to distortion and eventual ...

1985-03-01

98

[Neurodevelopmental follow-up of premature children in Lausanne and Geneva].  

Science.gov (United States)

Preterm children born before 32 weeks of gestation represent 1% of the annual births in Switzerland, and are the most at risk of neurodevelopmental disabilities. A neurological surveillance is thus implemented in the neonatal units, and multidisciplinary neurodevelopmental follow-up is offered to all our preterm patients. The follow-up clinics of the University hospitals in Lausanne and Geneva follow the Swiss guidelines for follow-up. An extended history and neurological examination is taken at each appointment, and a standardized test of development is performed. These examinations, which take place between the ages of 3 months and 9 years old, allow the early identification and treatment of developmental disorders frequent in this population, such as motor, cognitive or behavioral disorders, as well as the monitoring of the quality of neonatal care. PMID:21452511

2011-02-23

99

Susceptibility to invasive bacterial infections in children with sickle cell disease  

British Library Electronic Table of Contents (United Kingdom)

Individuals with sickle cell disease (SCD) demonstrate an increased susceptibility to invasive bacterial infections (IBI). The most common organisms causing IBI are Streptococcus pneumoniae, nontyphi Salmonella species and Haemophilus influenzae type b (Hib). IBI are the most common causes of death in children below 5 years of age with SCD. Increased susceptibility to IBI is because of several factors including dysfunctional antibody production and opsonophagocytosis as well as defective splenic clearance. Early diagnosis of Hib and pneumococcal infections combined with antibiotic prophylaxis and immunization programs, could lead to significant improvements in mortality, especially in Africa. Pediatr Blood Cancer. 2010;55:401-406. Copyright 2010 Wiley-Liss, Inc.

2010-01-01

100

Effect of age-at-weaning on digestive capacity of white seabream (Diplodus sargus)  

British Library Electronic Table of Contents (United Kingdom)

White seabream (Diplodus sargus) is today recognized as a potential species for Mediterranean aquaculture. Still, scarce information exists on weaning practices in order to reduce the live food period. This study aims to evaluate the effect of an early weaning on fish larvae digestive enzymes activities. In order to accomplish this, larvae were weaned with an inert diet at 20days after hatching (DAH) (feeding regime W20) and a control group was weaned at 27DAH (feeding regime W27). Before weaning, the onset and development of the main digestive enzymes were studied. The pattern of variation of digestive enzymes activities were analyzed at 0, 2, 9, 13 and 20DAH, and from then on at 0, 1 and 3weeks after diet introduction; that is, at 20, 27 and 41days for feeding regime W20, and days 27, 34...

2010-01-01

101

Description of Cretaceous Sedimentary Sequence of the Yaojia Formation Recovered by CCSD-SK-Is Borehole in Songliao Basin: Lithostratigraphy, Sedimentary Facies and Cyclic Stratigraphy  

British Library Electronic Table of Contents (United Kingdom)

The Yaojia Formation recovered by CCSD-SK-Is borehole (China Cretaceous Continental Scientific Drilling-SongkeI-the south borehole) is 157.67 m long and 99.96% of cores recovery. The age of the formation corresponds with a range from the Santonian to the early Campanian. The sequences and processes of lithology-lithofacies and cyclic stratigraphy are revealed by a detailed core description. Eleven rock types and three kinds of sedimentary subfacies, including shallow lake, deep lake, and delta front, are recognized from the drilling core. There are eleven sedimentary microfacies including dolostone, argillaceous limestone, shallow lake turbidite, deep lake turbidite, subaqueous mouth bar, distal bar, sheet sandstone, subaqueous distributary bay, slump deposits, shallow lake mudstone, and d...

2009-01-01

102

Treatment of proliferative haemangiomas with the 585 nm pulsed dye laser.  

Science.gov (United States)

Haemangiomas usually develop within the first few weeks of life, most regressing spontaneously before the age of 7 years. Some may ulcerate or compromise a vital function, in which case systemic corticosteroids, surgery or radiotherapy may be helpful. All of these treatment modalities are associated with significant morbidity. Treatment with the 585 nm flashlamp pulsed dye laser is safe and effective in the management of superficial vascular malformations. We report seven patients, under 12 months of age, who presented with proliferative haemangiomas, causing functional impairment. Ulcerated lesions were present in four patients. The patients were treated with the 585 nm pulsed dye laser (fluences 7.0-9.25 J/cm2), at intervals of 4-8 weeks. All of the lesions showed a significant reduction in size, together with improvement in the colour and integrity of the overlying skin. Treatment with the 585 nm pulsed dye laser should be considered in the ...

1996-04-01

103

Long-term effects of prenatal x-ray of human females: reproductive experience  

Energy Technology Data Exchange (ETDEWEB)

A cohort of singleton black human females exposed to diagnostic x-ray in utero and controls matched by parity, hospital of birth and birthdate have been followed to ages 25 to 30 years in Baltimore, Maryland. The search for possible effects of prenatal irradiation has focused on health, growth, development, and reproductive experience of exposed and control women. This paper reports findings related to reproductive experience. From an original data set of 1458 matched exposed-control pairs of women, questionnaire responses were received from 1109 exposed and 1124 control women including 852 each from pairs in which both the exposed and control woman responded. After careful search for alternative explanations of the findings, the authors concluded that females exposed in utero to low doses of x-ray (probably 1 to 5 rads) had significant increases in their rates of early onset of menses, births at age 15 years or less, ...

1981-09-01

104

HD 100453: A Link Between Gas-Rich Protoplanetary Disks and Gas-Poor Debris Disks  

CERN Document Server

HD 100453 has an IR spectral energy distribution (SED) which can be fit with a power-law plus a blackbody. Previous analysis of the SED suggests that the system is a young Herbig Ae star with a gas-rich, flared disk. We reexamine the evolutionary state of the HD 100453 system by refining its age (based on a candidate low-mass companion) and by examining limits on the disk extent, mass accretion rate, and gas content of the disk environment. We confirm that HD 100453B is a common proper motion companion to HD 100453A, with a spectral type of M4.0V - M4.5V, and derive an age of 10 +/- 2 Myr. We find no evidence of mass accretion onto the star. Chandra ACIS-S imagery shows that the Herbig Ae star has L_X/L_Bol and an X-ray spectrum similar to non-accreting Beta Pic Moving Group early F stars. Moreover, the disk lacks the conspicuous Fe II emission and excess FUV continuum seen in spectra of actively accreting Herbig Ae stars, ...

2009-01-01

105

Carbonate shoreline sedimentation in San Andres Formation, Lincoln County, New Mexico  

Energy Technology Data Exchange (ETDEWEB)

The Permian San Andres Formation of late Leonardian-early Guadalupian age is a significant hydrocarbon producer and crops out over a large area in south-central New Mexico. However, since its definition in 1909, the age and depositional environment of this unit have been questioned. In 1971 in Pecos County, Vincent Kelly divided the unit into three members: Rio Bonito, Bonney Canyon, and Fourmile Draw. The lowest member, although named for the Rio Bonito, has a type section designated at Sunset along U.S. Highway 70/380. Two miles east of Sunset, near Riverside, on the Rio Bonito, the Rio Bonito Member is exposed in a long series of roadcuts. Petrographic investigation of these rocks reveals an alternating sequence of high to low-energy intertidal to subtidal facies marked by oolitic and fossiliferous dolocalcarenite interbedded with dolomitic mudstone. The unit has been recrystallized and stylolites are abundant, as is ...

1986-03-01

106

Age sensitivity of juvenile mussels (Utterbackia imbeciles Say) to copper and cadmium exposure  

Energy Technology Data Exchange (ETDEWEB)

In recent years, there has been increased interest in using early life stages of freshwater bivalves to test the toxicity of dissolved constituents in water. The authors have developed laboratory and in situ assays with artificially cultured Utterbackia imbecillis to examine effects of contaminants and existing conditions in embayments and rivers on mortality and reproductive success of unionid mussels. Age sensitivity of U. imbecillis to Cd and Cu was examined using both static acute and 8-day static renewal bioassays. Both aqueous and sediment exposures demonstrated greater sensitivity to Cd than Cu. LC{sub 50}`s for two-day old (2d) and 9d mussels were approximately half the LC{sub 50} calculated for 16d mussels in 48-hr bioassays with Cd. Additionally, acute assays were repeated twice to examine variability in response between different mussel cultures to the two metals. The results of this work reinforce the potential of juvenile U. ...

1994-12-31

107

Surgical approach for high-energy posterior tibial plateau fractures  

UK PubMed Central (United Kingdom)

Background:High-energy fractures of posterior tibial plateau always need surgical treatment. Generally, posterior fragments of these fractures could not be exposed and reduced...Full Text Available

2011-03-01

108

Older hip fracture patients: three groups with different needs  

UK PubMed Central (United Kingdom)

BackgroundNorway, and particularly Oslo, has the highest reported incidence of hip fractures in the world. It is increasingly common to care for older hip fracture patients in orthogeriatric...Full Text Available

109

Non-traumatic fractures following seizures: two case reports  

UK PubMed Central (United Kingdom)

IntroductionSeizures with or without trauma may cause fractures that occur commonly in epileptic seizures. Fracture risk is less reported in non-epileptic seizures. Some metabolic...Full Text Available

110

Efficacy and cost-effectiveness of nutritional intervention in elderly after hip fracture: design of a randomized controlled trial  

UK PubMed Central (United Kingdom)

BackgroundHip fracture patients often have an impaired nutritional status at the time of fracture, which can result in a higher complication rate, prolonged rehabilitation time and...Full Text Available

111

Cement-based composites: Strain rate effects on fracture  

Energy Technology Data Exchange (ETDEWEB)

This book contains over 20 selections. Some of the titles are: Continuum damage mechanics studies on the dynamic fracture of concrete; Dynamic compressive strength of cementitious materials; Rate-sensitivity of mode I and mode II fracture concrete; and An impact damage model of concrete.

1986-01-01

112

Addressing the Challenges Special Needs Students Face when Transitioning from the Classroom to the Workplace  

Science.gov (United States)

One of the biggest fears and challenges a parent of a child with special needs faces is navigating the post-22 landscape. When a child hits the age of 22, the Department of Elementary and Secondary Education (DESE) is no longer required to provide daily services and support. Whatever the abilities, or disabilities, of a child, every parent has the same concerns about how their child will productively fill their days and live as independently as possible without the safety net of the DESE. One of the transition paths most frequented is entering the workforce. Public and private schools alike work to teach their students the basic skills they need to work. In fact, the national Individuals with Disabilities Education Act (IDEA) states that students must have a transition plan in formulation by the age of 16. This article describes the vocational program developed by the League School of Greater Boston which specifically addresses the challenges ...

2010-10-01

113

Stress fracture of the clavicle associated with sternocostoclavicular hyperostosis  

Energy Technology Data Exchange (ETDEWEB)

We report a case of stress fracture of the clavicle associated with sternocostoclavicular hyperostosis. A 60-year-old man sustained a stress fracture of the right clavicle with no history of trauma. On radiography, hyperostosis of the anterior chest wall and ankylosis of the sternoclavicular joint were evident in addition to the fracture. Fracture healing was uneventful after 2.5 months. Ankylosis of the sternoclavicular joint may have caused increased stress at the midshaft of the clavicle by daily activity or minor trauma. Such a fracture is a rare complication of sternocostoclavicular hyperostosis. (orig.)

2005-07-01

114

Multi-Phase Fracture-Matrix Interactions Under Stress Changes  

Energy Technology Data Exchange (ETDEWEB)

The main objectives of this project are to quantify the changes in fracture porosity and multi-phase transport properties as a function of confining stress. These changes will be integrated into conceptual and numerical models that will improve our ability to predict and optimize fluid transport in fractured system. This report details our progress on: (a) developing the direct experimental measurements of fracture aperture and topology and fluid occupancy using high-resolution x-ray micro-tomography, (b) counter-current fluid transport between the matrix and the fracture, (c) studying the effect of confining stress on the distribution of fracture aperture and two-phase flow, and (d) characterization of shear fractures and their impact on multi-phase flow. The three-dimensional surface that describes the large-scale structure of the fracture ...

2005-12-07

115

Update on the oxidative stress theory of aging: Does oxidative stress play a role in aging or healthy aging?  

UK PubMed Central (United Kingdom)

The oxidative stress theory of aging predicts that manipulations that alter oxidative stress/damage will alter aging. The gold standard for determining whether aging is altered is lifespan,...Full Text Available

2010-03-01

116

Study of fractures in cast parts of high-strength aluminum alloy  

Energy Technology Data Exchange (ETDEWEB)

Results are presented from studies on the quality of cast parts made by counterpressure casting of high-strength aluminum alloy AMKh-605, and Al-Cu-Mn-Cr alloys (5.6-6.4% Cu, 0.25-0.55% Mn, 0.20-0.55% Cr, 0.20-0.45% Ti, 0.08-0.25% Zr, less than or equal to0.25% Fe, less than or equal to0.25% Si, less than or equal to0.05% Mg). Chill castings were heat treated by quenching from 450/sup 0/C (20 hours) in water, aging at 160/sup 0/C for five hours with cooling in air. Fractograms of tensile specimens are presented. Scanning electron microscopy allows an ambiguous determination of the cause of failure of a part, be it at initial crystallization crack defects or burns, and also allows a relationship to be established between structure and mechanical properties.

1985-03-01

117

Promising materials for HTGR high temperature heat exchangers  

International Nuclear Information System (INIS)

The service conditions for high-temperature heat-exchangers with helium coolant of HTGRs and requirements imposed on materials for their production are discussed. The choice of nickel-base alloys with solid-solution hardening for long-term service at high temperatures is grounded. Results of study on properties and structure of types Ni-25Cr-5W-5Mo and Ni-20Cr-20W alloy in the temperature range of 900 deg. - 1,000 deg. C are given. The ageing of Ni-25Cr-5W-5Mo alloy at 900 deg. - 950 deg. C results in decreased corrosion-mechanical properties and is caused by the change of structural metal stability. Alloy with 20% tungsten retains a high stability of both structure and properties after prolonged exposure in helium at above temperatures. The alloy has also increased resistance to delayed fracture and low-cycle fatigue at high temperatures. The developed alloy of type Ni-20Cr-20W with microalloying is recommended for production of tubes for HTGR ...

1989-06-01

118

Optimizing the microstructure of implant alloy TiAl5Fe2.5 by microprobe analysis  

International Nuclear Information System (INIS)

For optimizing the microstructure of the (#alpha# + #beta#)-titanium alloy TiAl5Fe2.5 the content of the two alloying elements aluminium and iron in the #alpha#- and #beta#-phase was determined by microprobe analysis. The alloys with the composition of the #alpha#- and of the #beta#-phase at 850 degC TiAl6Fe0.5 (#alpha#-phase) and TiAl3.5Fe6.5 (#beta#-phase) were prepared by arc melting and rolling at 850 degC. The mechanical properties of the '#alpha#'- and of the '#beta#'-phase-alloy are compared with the properties of the (#alpha# + #beta#)-alloy TiAl5Fe2.5 in the as rolled and swaged condition and after an additional aging at 550 degC. By this optimizing process it was possible to achieve a tensile strength of Rsub(m) = 1012 N/mm"2, an yield strength of Rsub(p0.2) 954 N/mm"2 and an elongation at fracture A = 14.5% in the TiAl5Fe2.5-alloy, although the degree of hot deformation was small. By a higher degree of deformation these properties ...

1985-05-13

119

Local control and sequelae following irradiation of Ewing's sarcoma  

International Nuclear Information System (INIS)

135 patients with histologically proven Ewing's sarcoma, treated at the Institute Gustave Roussy between 1960-1974 were reviewed in order to establish the effectiveness and the complications associated with radiotherapy. In 133 patients, a dose of at least 60 Gy for long bones, 55 Gy for flat bones and 45 Gy for vertebrae was given. 26 major complications (of which more than one occured in certain patients) were observed: 12 cases of growth retardation, loss of joint function in 7 cases, 3 fractures, 2 osteonecroses, 2 cases of delayed healing, one massive soft tissue fibrosis, 1 abdominocutaneous fistula, 2 cases of symptomatic pulmonary fibrosis with associated infection, 2 cases of radiation enteropathy, 2 of mammary hypoplasia and 1 osteosarcoma developing in an irradiated zone. These complications necessitated 12 surgical interventions, including 4 disarticulations or amputations. The incidence of complications can be related to the age of ...

120

Fundamental study on evaluation method for alkali-resistance of fibers. Kakushu sen'i no tai arukarisei no hyokaho ni kansuru kiso kenkyu  

Energy Technology Data Exchange (ETDEWEB)

In order to clarify the alkali-resistance of fibers to be utilized as reinforcing materials for concrete, such as glass fiber, Aramid fiber, and carbon fiber, accelerated aging tests in alkaline solution were conducted. In detail, the degree of degradation of the fracture strength and Young's modulus were investigated through static tensile strength tests after soaking in alkaline solution of these fibers and then the mechanism of degradation was examined by observation using a scanning electron microscope. The conclusion obtained was as follows. Glass fiber was easily degraded in the alkaline solution and the progress of degradation was simulated quantitatively by the method proposed in this paper, which was based on a diffusion theory. Both Aramid fiber and carbon fiber showed a significant alkali-resistance without degrading. The reaction of glass fiber with alkaline solution proceeded uniformly from the surface of glass fiber into ...

1994-05-20

121

Environmental cracking of the alpha-beta titanium alloy, Ti-6Al-6V-2Sn  

International Nuclear Information System (INIS)

The combined effects of environment, yield strength and stress state on the cracking susceptibility of beta-extruded Ti-6Al-6V-2Sn have been examined. At a constant yield strength and under plane strain conditions, the stress intensity required for slow crack propagation decreased as the severity of the environment increased, i.e., from laboratory air to 3.5% NaCl. Furthermore, the crack propagation rates were a function of both stress intensity, and environmental severity. Although the fracture toughness and threshold stress intensities for slow crack growth generally decreased with increasing yield strength, aging, which resulted in the precipitation of ordered Ti3Al particles in the primary alpha phase, tended to accentuate the susceptibility of this alloy to sustained load/stress corrosion cracking. Finally, at constant yield strength, the sustained load cracking threshold stress intensity was a function of stress state.

122

Cementless bipolar hemiarthroplasty in femoral neck fractures in elderly  

UK PubMed Central (United Kingdom)

Background:Cemented hip arthroplasty is an established treatment for femoral neck fracture in the mobile elderly. Cement pressurization raises intramedullary pressure and...Full Text Available

2011-05-01

123

Brief guide to the MINC-method for modeling flow and transport in fractured media  

Science.gov (United States)

MINC stands for Multiple INteracting continua.'' It is an approximate method for modeling fluid and heat flow in fractured- porous media, developed by Pruess and Narasimhan (1982, 1985) at the Lawrence Berkeley Laboratory. The method is applicable to flow processes in which an important aspect is the exchange of fluid, heat, or chemical species between fractures and unfractured rock. Examples include production and injection operations in fractured geothermal reservoirs, water-flooding, steamflooding, and other methods for enhanced oil recovery from fractured reservoirs, as well as chemical transport and contaminant migration in fractured rock. MINC can only be applied to media in which the fractures are sufficiently well connected so that a continuum treatment of flow in the fracture network can be made.

1992-05-01

124

Analysis of in-situ fracture of oil sand formations by explosives  

Energy Technology Data Exchange (ETDEWEB)

An analytical model is proposed for the design and simulation of in-situ fracture of deep oil sand formations. This model is based on the finite element variational principle in conjunction with special empirical modules to characterize in-situ oil sands behavior. A computer code by the name of SANFRAC was developed to handle the dynamic fracture of formations induced by explosives. Simulation of hydraulic fracture processes can be treated by the same code as special cases using the quasi-static analysis. Numerical case studies by the SANFRAC code indicate that extensive horizontal fracture can be achieved by dynamic loads with proper fracture starters configured at the injection well. The unique advantage of the dynamic fracturing technique over the hydraulic fracture methods is also demonstrated by these studies.

1987-03-01

125

A retrospective analysis of bilateral fractures over sixteen years: localisation and variation in treatment of second hip fractures  

British Library Electronic Table of Contents (United Kingdom)

The aim of this study was the evaluation of contralateral hip fractures after a previous hip fracture. For this retrospective analysis patients were selected from the database of the LUMC, a teaching hospital in the south-west of the Netherlands. We analyzed all patients with a second fracture of a hip between 1992 and 2007. The exclusion criteria were high impact trauma and patients with diseases or medication known to have a negative effect on bone metabolism. A total of 1,604 hip fractures were identified. The possible predictive factors for the second fracture and descriptive statistics related to surgery (Hb and HT before and after the operation, total amount of intra- and postoperative blood loss, type of osteosynthesis, complications, time of death after the last fracture, time betw...

2011-01-01

126

Prospective evaluation of femoral head viability following femoral neck fracture  

International Nuclear Information System (INIS)

The bone scans of 33 patients (pts) with recent subcapital fractures (fx) of the femur were evaluated prospectively to determine their value in predicting femoral head visability. Each of the 33 pts (ll men, 22 women, age range 30-92) had a pre-operative bone scan within 72 hrs of the fx (23 pts within 24 hrs). Anterior and posterior planar views of both hips and pinhole views (50% of pts) were obtained 2 hrs after administration of Tc-99m HDP. The femoral head was classified as perfused if it showed the same activity as the opposite normal side or if it showed only slightly decreased activity. Femoral heads showing absent activity were classified as nonperfused. Overall, 20 of the 33 pts showed a photopenic femoral head on the side of the fx. Only 2 pts showed increased activity at hte site of the fx. Internal fixation of the fx was performed in 23 pts, 12 of whom had one or more follow-up scans. Five of these 12 pts showed absent femoral head ...

1984-06-05

127

Evaluation of the hemodynamics of the femoral head compared with the ilium, femoral neck and femoral intertrochanteric region in healthy adults. Measurement with positron emission tomography (PET)  

International Nuclear Information System (INIS)

Non-traumatic osteonecrosis of the femoral head (ONF) is considered to be a disease that occurs primarily due to ischemia of the femoral head, while its etiology and pathology are not fully understood. It is therefore necessary to identify the characteristics of the hemodynamics of the femoral head. In this study, the hemodynamics in the ilium and proximal regions of the femur, including the femoral head, was investigated using positron emission tomography (PET). The subjects of this study consisted of 8 hip joints of four healthy male adults and 3 hip joints on the contralateral side of a femoral neck fracture, avulsion fracture of the greater trochanter and coxarthrosis (1 case each, all females) for a total of 11 hip joints of 7 subjects. The ages of the subjects ranged from 25 to 87 years (average age: 54 years). Blood flow was measured by means of the H_2"1"5O dynamic study method and blood volume ...

2005-10-01

128

The Importance of Mitochondrial DNA in Aging and Cancer  

UK PubMed Central (United Kingdom)

Mitochondrial dysfunction has been implicated in premature aging, age-related diseases, and tumor initiation and progression. Alterations of the mitochondrial genome accumulate both in aging tissue...Full Text Available

129

Mitochondria and PGC-1? in Aging and Age-Associated Diseases  

UK PubMed Central (United Kingdom)

Aging is the most significant risk factor for a range of degenerative disease such as cardiovascular, neurodegenerative and metabolic disorders. While the cause of aging and its associated diseases...Full Text Available

131

Natural fracture characterization using passive seismic illumination  

Energy Technology Data Exchange (ETDEWEB)

The presence of natural fractures in reservoir rock can significantly enhance gas production, especially in tight gas formations. Any general knowledge of the existence, location, orientation, spatial density, and connectivity of natural fractures, as well as general reservoir structure, that can be obtained prior to active seismic acquisition and drilling can be exploited to identify key areas for subsequent higher resolution active seismic imaging. Current practices for estimating fracture properties before the acquisition of surface seismic data are usually based on the assumed geology and tectonics of the region, and empirical or fracture mechanics-based relationships between stratigraphic curvature and fracturing. The objective of this research is to investigate the potential of multicomponent surface sensor arrays, and passive seismic sources in the form of local earthquakes ...

2003-01-08

132

Fracture characterizatioin of the Bandelier tuff in OU-1098 (TA-2 and TA-41)  

Energy Technology Data Exchange (ETDEWEB)

Rock fracture characterization documents a total of 1496 fractures in unit 2 of the Tshirege Member of the Bandelier Tuff along 6013 feet of Los Alamos Canyon`s north wall adjacent to Operational Unit 1098. Geologically termed joints, these fractures likely owe their primary origin to brittle failure during the cooling contraction of the tuff after its emplacement nearly 1 million years ago. Subsequent tectonic movement along the Pajarito Fault system has modified fracture strikes, dips, apertures, and linear density. From a background linear density of approximately 20 fractures per 100-foot interval along the canyon wall, fracture density increases to values in excess of 50 fractures per 100-foot interval in a zone at and immediately east of the Omega West reactor building TA-2-1. This increase in fracture density is ...

1996-10-01

133

Role of positron emission tomography-computed tomography in staging and early chemotherapy response evaluation in children with neuroblastoma  

International Nuclear Information System (INIS)

To evaluate the role of positron emission tomography-computed tomography (PET-CT) in staging and determining early treatment response to chemotherapy in children with neuroblastoma (NB) and its correlation with the final outcome. Patients and Methods: Seventeen patients of NB with mean age of 51.5 months (age range 2-132 months; 14 males, 3 females) underwent serial "1"8F-fluorodeoxyglucose (FDG) PET-CT imaging. All 17 patients were for staging before any treatment. Twelve of 17 patients underwent "1"3"1I meta-iodobezylguanidine (MIBG) scan and bone scan. MIBG uptake was seen in the primary lesion in 11/12 patients. MIBG uptake in bones was seen in 3/12 patients. All bone lesions were concordant on MIBG and bone scan. Early response to chemotherapy was evaluated after two cycles using PET-CT. A 30% reduction in longest diameter was taken as cut-off value for response on CT based on the response ...

134

THE INFLUENCE OF GRAIN BOUNDARY CARBIDE ...  

Science.gov (United States)

... Title : THE INFLUENCE OF GRAIN BOUNDARY CARBIDE DENSITY ON THE BRITTLE FRACTURE OF FERRITE PEARLITE STEELS. ...

135

N7'5 20853  

Science.gov (United States)

of fracture -stimulated geothermal reservoirs; 2) the development of ... of the mathematical simulation model of geothermal reservoirs. ...

138

Fracture imaging with converted elastic waves  

Energy Technology Data Exchange (ETDEWEB)

This paper examines the seismic signatures of discrete, finite-length fractures, and outlines an approach for elastic, prestack reverse-time imaging of discrete fractures. The results of this study highlight the importance of incorporating fracture-generated P-S converted waves into the imaging method, and presents an alternate imaging condition that can be used in elastic reverse-time imaging when a direct wave is recorded (e.g., for crosswell and VSP acquisition geometries).

2001-05-29

140

Microstructure, mechanical properties and fracture behavior of #alpha# particle irradiated type 316 stainless steel  

International Nuclear Information System (INIS)

The present work is a research of the effect of helium on the microstructure, mechanical properties and fracture behaviors of a type 316 austenitic steel. Helium implantation was performed by 30-MeV #alpha#-particle injection on very small size specimens, using a cyclotron. Average helium content in a He-deposited region was up to 2000 appm He. In the case of 2000appm He implantation, intergranular fracture was sometimes observed on the helium deposited region after tensile test at room temperature. At elevated temperature test, however, this material showed the transition of fracture mode from transgranular-ductile fracture at 773K to intergranular fracture at 873. In the case of 500 appm He implantation, the transition of fracture mode was recognized at a temperature range of 873K to 973K. (author).

141

Geometry of elastic hydrofracturing by injection of an over pressured non-Newtonian Fluid  

CERN Document Server

The nucleation and propagation of hydrofractures by injection of over pressured fluids in an elastic and isotropic medium are studied experimentally. Non-Newtonian fluids are injected inside a gelatine whose mechanical properties are assumed isotropic at the experimental strain rates. Linear elastic theory predicts that plastic deformation associated to breakage of gelatin bonds is limited to a small zone ahead of the tip of the propagating fracture and that propagation will be maintained while the fluid pressure exceeds the normal stress to the fracture walls (Ch\\'avez-\\'Alvarez,2008) (i.e., the minimum compressive stress), resulting in a single mode I fracture geometry. However, we observed the propagation of fractures type II and III as well as nucleation of secondary fractures, with oblique to perpendicular trajectories with respect to the initial ...

2009-01-01

142

Bilateral femoral neck fractures following pelvic irradiation  

International Nuclear Information System (INIS)

Over 300 cases of femoral neck fractures following radiotherapy for intrapelvic malignant tumor have been reported in various countries since Baensch reported this disease in 1927. In Japan, 40 cases or so have been reported, and cases of bilateral femoral neck fractures have not reached to ten cases. The authors experienced a case of 75 year-old female who received radiotherapy for cancer of the uterus, and suffered from right femoral neck fracture 3 months after and left femoral neck fracture one year and half after. As clinical symptoms, she had not previous history of trauma in bilateral femurs, but she complained of a pain in a hip joint and of gait disturbance. The pain in left femoral neck continued for about one month before fracture was recognized with roentgenogram. As histopathological findings, increase of fat marrow, decrease of bone trabeculae, and its marked ...

143

Radiation therapy for Kasabach-Merritt syndrome. Analysis of unfavorable factors in 5 children  

Energy Technology Data Exchange (ETDEWEB)

During the past 10 years, five infants with Kasabach-Merritt syndrome (K-M) receiving radiation therapy were reported. We investigated whether radiation therapy for K-M was useful and what the unfavorable factors of K-M were. During the past 10 years, we have treated five infants with K-M. The syndrome occurred at ages ranging from birth to 4 months. The incidence of female to male ratio was 3:2. Among 5 cases, the site of hemangioma was as follows; shoulder, anterior chest wall, lower abdominal wall, face and neck and inguinal site. All 5 cases received medication to control the coagulopathy including prednisone and blood transfusion at first. Because the platelet count and the bleeding tendency did not improve in any case, these cases received radiation therapy. Total dose ranged from 5 to 10 Gy and fraction-size ranged from 0.5 to 1.75 Gy. Irradiation session was 2 or 3 times per week. In 5 cases, 4 cases showed cure of bleeding tendency and disappearance of ...

1996-03-01

144

Functional magnetic resonance imaging of the normal and abnormal visual system in early life.  

DEFF Research Database (Denmark)

Functional magnetic resonance imaging (fMRI) in young children may provide information about the development of the visual cortex, and may have predictive value for later visual performance. The purpose of this study was to evaluate the usefulness of fMRI for examining cerebral processing of vision in very young infants and in infants with brain damage. We examined 15 preterm infants, 12 children suspected of having a cerebral visual impairment and 10 children with a normal visual system, all of whom were either spontaneously asleep or sedated with chloral hydrate. Cortical response to stroboscopic light stimulation could be demonstrated in all technically acceptable data sets from children with a post-menstrual age (PMA) of > 41 weeks, but not in younger infants. Children < 60 weeks PMA showed either a blood oxygenation level-dependent (BOLD) signal increase or decrease, while all older children showed a signal decrease. The activated cortical volumes showed ...

2000-01-01

146

Emerging technologies for academic libraries in the digital age  

CERN Document Server

Emerging technologies for academic libraries in the digital age

2009-01-01

147

Pre-waste-emplacement ground-water travel time sensitivity and uncertainty analyses for Yucca Mountain, Nevada; Yucca Mountain Site Characterization Project  

Energy Technology Data Exchange (ETDEWEB)

Yucca Mountain, Nevada is a potential site for a high-level radioactive-waste repository. Uncertainty and sensitivity analyses were performed to estimate critical factors in the performance of the site with respect to a criterion in terms of pre-waste-emplacement ground-water travel time. The degree of failure in the analytical model to meet the criterion is sensitive to the estimate of fracture porosity in the upper welded unit of the problem domain. Fracture porosity is derived from a number of more fundamental measurements including fracture frequency, fracture orientation, and the moisture-retention characteristic inferred for the fracture domain.

1993-01-01

148

Back pain in the osteoporotic individual: A physiatric approach  

British Library Electronic Table of Contents (United Kingdom)

Back pain from osteoporosis is commonly related to compression fractures. The patient with vertebral compression fractures additionally suffers from an ongoing risk of recurrent fractures and postural abnormalities that can result in impaired respiratory function, leading to increased risk of morbidity. Weakened back muscles, especially the back extensor group, are felt to contribute significantly to this risk. The combination of pharmacologic and nonpharmacologic interventions, through physical activity, exercise, and modalities, are potential interventions that could be used to help reduce the pain of osteoporotic compression fractures as well as potentially reducing recurrent fracture rates.

2011-01-01

150

Extracting energy from hydraulically-fractured geothermal reservoirs  

Science.gov (United States)

The governing equations for heat and mass transfer were derived for hydraulically fractured geothermal reservoirs. When converted to nondimensional form it was shown that the equations can be considerably simplified. The resulting equations can be strongly influenced by the effects of buoyancy; the magnitude of the effect is measured by the ratio of the Grashof and Reynolds numbers, and the ratio of the actual permeability of the fracture and the square of the fracture gap width. Significant quantities of energy can be extracted from hydraulic fractures--even without thermal stress fracturing. The amount is limited by the size of the fracture and the low thermal conductivity of rock. The viscous pressure drop in open fractures is insignificant, and depending upon losses in piping and surface equipment, the entire system could be ...

1976-01-01

151

Transcription from the SV40 early-early and late-early overlapping promoters in the absence of DNA replication.  

UK PubMed Central (United Kingdom)

Transcription for a hybrid SV40 promoter-beta globin coding sequence recombinant initiates from both early-early (EE) and late-early (LE) SV40 start sites (EES and LES) in the absence of DNA replication....Full Text Available

1983-01-01

152

Well Test Analysis in Naturally Fissured, Geothermal Reservoirs with Fracture Skin  

Science.gov (United States)

Mineral deposition or alteration is commonly found at fracture-block interfaces is fissured, geothermal reservoirs. In response to pressure reduction in the fissures such mineralization, if less permeable than the matrix rock, will retard the flow of fluid from the blocks to the fissures and is termed fracture skin in this paper. The problem of fluid flow to a production well in a double-porosity reservoir with fracture skin was analyzed theoretically. One of the findings of the analysis was that fully transient block-to-fissure flow can be approximated by pseudo-steady state flow if fracture skin permeability is sufficiently low. Type curves generated by numerical inversion of Laplace transform solutions are used to cooroborate the results of a finite-difference model of steam transport to a well in a naturally fissured, geothermal reservoir with fracture skin.

1983-12-15

153

Some mismatches occurred when simulating fractured reservoirs as homogeneous porous media  

Science.gov (United States)

The understanding of transport processes that occur in naturally fractured geothermal systems is far from being complete. Often, evaluation and numerical simulations of fractured geothermal reservoirs, are carried out by assuming equivalent porous media and homogeneous petrophysical properties within big matrix blocks. The purpose of this paper, is to present a comparison between results obtained from numerical studies of a naturally fractured reservoir treated as a simple porous medium and the simulation of some real aspects of the fractured reservoir. A general conclusion outlines the great practical importance of considering even approximately, the true nature of such systems. Our results show that the homogeneous simplified evaluation of the energy resource in a fractured system, could result in unrealistic estimates of the reservoir capacity to generate ...

1996-01-24

154

Some mismatches occurred when simulating fractured reservoirs as homogeneous porous media  

Energy Technology Data Exchange (ETDEWEB)

The understanding of transport processes that occur in naturally fractured geothermal systems is far from being complete. Often, evaluation and numerical simulations of fractured geothermal reservoirs, are carried out by assuming equivalent porous media and homogeneous petrophysical properties within big matrix blocks. The purpose of this paper, is to present a comparison between results obtained from numerical studies of a naturally fractured reservoir treated as a simple porous medium and the simulation of some real aspects of the fractured reservoir. A general conclusion outlines the great practical importance of considering even approximately, the true nature of such systems. Our results show that the homogeneous simplified evaluation of the energy resource in a fractured system, could result in unrealistic estimates of the reservoir capacity to generate electricity.

1996-12-31

155

A numerical study on the long term thermo-poroelastic effects of cold water injection into naturally fractured geothermal reservoirs  

British Library Electronic Table of Contents (United Kingdom)

The residing fracture system and the prevailing in situ stresses have a significant impact on fluid flow and heat transfer in crystalline rocks. The long term response of fracture systems to changes in effective stresses, in particular the long term geo-mechanical effects of thermal stresses on reservoir characteristics is of particular interest to the geothermal industry.In this paper, a geothermal reservoir model is presented, in which a thermo-poroelastic finite element module is coupled to a fracture geomechanical module. This describes fracture closure as a function of effective stress and the changes in parameters, such as effective permeability, porosity and discrete fracture apertures. The novelty of this approach lies in its dynamic treatment of the characteristic properties of in...

2011-01-01

156

Soft tissue signal abnormality associated with eosinophilic granuloma. Correlation of MR imaging with pathologic findings  

Energy Technology Data Exchange (ETDEWEB)

Six patients with eosinophilic granuloma were studied retrospectively in order to correlate the MRI appearances with the pathology. Ages ranged from 2 years 6 months to 11 years. The bones involved were the humerus, ulna, radius, femur, clavicle and ilium. Plain films, MRI and pathology specimens were obtained. A lytic lesion with indistinct margins, endosteal erosions and periosteal reaction was seen in all cases on plain radiographs. Bone marrow signal was decreased on T1-weighted images and increased on T2-weighted images throughout the bony lesion in all cases. T2-weighted images showed extensive soft-tissue abnormalities suggesting inflammatory changes in four cases. In two cases abnormalities were limited. Extensive changes correlated histologically with an early phase lesion. Localized minor changes were associated with a mid-phase lesion. Inflammatory soft-tissue changes could be associated with eosinophilic granuloma. The size of the ...

1994-09-01

157

Perfusion impairments in children with reactive attachment disorder (RAD) on "9"9"mTc-ECD brain SPECT: comparison with MR findings  

International Nuclear Information System (INIS)

This study aimed to reveal that severe disturbance of attachment relationship with primary care-giver can affect functional and anatomical brain development by measuring cerebral perfusion on "9"9"mTc-ECD brain SPECT and correlative MRI. We included 18 children aged 31 to 76 months who met the diagnostic criteria of RAD as defined in DSM-IV and ICD-10 and SSP and CARS. "9"9"mTc-ECD SPECT was performed using CERASPECT. MRI was performed in all patients. SPECT data were visually assessed. 15 of 18 children had abnormal perfusion on SPECT, revealing decreased perfusion of Lt.thalamus (7/15) and Rt.thalamus (3/15), and bilateral thalami (5/15). Perfusion of basal ganglia was decreased in 8 children. Decreased perfusion of Lt. parietal area was seen in 2. Whereas, all patients had normal MR findings. Perfusion abnormalities involving thalamus, BG in most children with RAD were found in this study. These results suggest that brain development of infant could be impeded ...

2002-11-15

158

Online monitoring of power transformers - a new low-cost system for small and medium power transformers; Monitoring von Leistungstransformatoren - Jetzt auch fuer kleine und mittlere Baugroessen  

Energy Technology Data Exchange (ETDEWEB)

Until now, monitoring of power transformers focussed mainly large generator and network transformers. Siemens goes a step ahead and provides a system especially developed and designed for small and medium power transformers, e.g. for the 100 kV level. This low cost version could be achieved by restriction to really necessary measuring quantities. This allows to realize also for small and medium power transformers an online monitoring including an estimation of aging and as an option an early warning to avoid unexpected failures. (orig.) [German] Die Ueberwachung (Monitoring) von Leistungstransformatoren war bisher vor allem fuer Maschinentransformatoren und grosse Netzkuppeltransformatoren in der Diskussion. Siemens geht einen Schritt weiter und stellt nun auch ein System bereit, das speziell fuer kleine und mittlere Leistungstransformatoren, z.B. der 110-kV-Spannungsebene, konzipiert ist. Diese kostenguenstige Variante wurde durch ...

1999-09-20

159

Normal and abnormal water diffusion in the brain  

International Nuclear Information System (INIS)

Diffusion magnetic resonance imaging (MRI) has become an important tool in the radiologic diagnosis of diseases of the brain as it measures molecular motion of water that characterizes the microstructure of tissues. Its most important clinical use to date is the early detection of cerebral ischemia by revealing the ischemic injury shortly after vessel occlusion and simultaneously providing therapy-relevant information on the tissue at risk. Furthermore, diffusion MRI is diagnostically promising in other diseases of the brain and is thus increasingly becoming part of routine clinical protocols in the diagnosis of tumors, inflammation, trauma, demyelination, dysmyelination and neurodegeneration. Although abnormalities of diffusion are generally not pathognomonic, diffusion MRI affords information about tissue changes for specific disorders that complements information obtained with standard MR techniques and frequently shows pathology earlier. In addition, diffusion ...

2003-10-01

160

Iofetamine I 123 single photon emission computed tomography is accurate in the diagnosis of Alzheimer's disease  

Energy Technology Data Exchange (ETDEWEB)

To determine the diagnostic accuracy of iofetamine hydrochloride I 123 (IMP) with single photon emission computed tomography in Alzheimer's disease, we studied 58 patients with AD and 15 age-matched healthy control subjects. We used a qualitative method to assess regional IMP uptake in the entire brain and to rate image data sets as normal or abnormal without knowledge of subjects'clinical classification. The sensitivity and specificity of IMP with single photon emission computed tomography in AD were 88% and 87%, respectively. In 15 patients with mild cognitive deficits (Blessed Dementia Scale score, less than or equal to 10), sensitivity was 80%. With the use of a semiquantitative measure of regional cortical IMP uptake, the parietal lobes were the most functionally impaired in AD and the most strongly associated with the patients' Blessed Dementia Scale scores. These results indicated that IMP with single photon emission computed ...

1990-04-01

161

Evaluation of craniosynostosis surgery. Technetium-99m-HMPAO SPECT cerebral blood flow study in children with craniosynostosis  

International Nuclear Information System (INIS)

Premature fusion of multiple cranial sutures has been associated with increased intracranial pressure and the potential for mental impairment. Isolated craniosynostosis, however, is considered a benign condition primarily reconstructed for aesthetic purposes. A comparative analysis, to assess the differences between pre- and post operatory cerebral perfusion of patients who underwent surgery for simple cranisynostosis, was performed using single positron emission computed tomography ''SPECT'' Images. Cerebral blood flow studies were performed using "9"9"mTc-HMPAO SPECT in children with simple cranisynotoses. The subjects were 8 children with craniosynostosis (age, 2 months-9 years). Preoperative revealed regional hypovascularity in the cerebral hemisphere in 5 cases (62%). In 6 patients the cerebral blood flow normalized or increased after craniofacial reconstruction. We demonstrated the presence of regional hypovascularity in the cerebral hemisphere of simple ...

1998-09-01

162

CT appearances of unilateral cleft palate 20 years after bone graft surgery  

Energy Technology Data Exchange (ETDEWEB)

Purpose: To describe CT appearances in patients with unilateral cleft lip and palate (CLP) 20 years after bone graft surgery. Material and Methods: Eighteen consecutive patients with unilateral CLP were examined. All patients had been treated with primary closure, both in infancy and early childhood, supplemented with bone grafting at the age of around 10 years. The CT examination of the upper jaw included a dental CT program. The CT appearances of the cleft side were compared with those of the untreated non-cleft side. Results: Abnormal CT appearances included skew nasal aperture (n=17), nasal septal deviation (n=17), low floor of nasal aperture (n=15) at or towards the cleft side, and deviation of anterior nasal spine towards the non-cleft side (n=18). The posterior part of the bone cleft was visible in all patients, and the dental arch was V-shaped in 8. Conclusion: Although adherence to the present treatment protocol is considered to give ...

2002-11-01

163

CT appearances of unilateral cleft palate 20 years after bone graft surgery  

International Nuclear Information System (INIS)

Purpose: To describe CT appearances in patients with unilateral cleft lip and palate (CLP) 20 years after bone graft surgery. Material and Methods: Eighteen consecutive patients with unilateral CLP were examined. All patients had been treated with primary closure, both in infancy and early childhood, supplemented with bone grafting at the age of around 10 years. The CT examination of the upper jaw included a dental CT program. The CT appearances of the cleft side were compared with those of the untreated non-cleft side. Results: Abnormal CT appearances included skew nasal aperture (n=17), nasal septal deviation (n=17), low floor of nasal aperture (n=15) at or towards the cleft side, and deviation of anterior nasal spine towards the non-cleft side (n=18). The posterior part of the bone cleft was visible in all patients, and the dental arch was V-shaped in 8. Conclusion: Although adherence to the present treatment protocol is considered to give ...

2002-11-01

164

Body and brain development following exposure to "6"0Co #gamma#-irradiation during pregnancy in mice  

International Nuclear Information System (INIS)

We studied the dose-response effects of #gamma#-irradiation on the weight gains of the body and the brain in ICR mice exposed to various doses of "6"0Co #gamma#-irradiation ranging from 0 to 1.5 Gy on day 13 of pregnancy (E13). We found that 0.5 Gy #gamma#-irradiation caused a significant reduction in brain weight but not in body weight among 6-week-old mice. Higher doses (1.0, 1.5 Gy) seriously inhibited body and brain development, resulting in significantly low weights at 6 weeks of age. A significantly lower brain weight among fetuses exposed to 1.5 Gy was found as early as 24 hours after exposure, while significant reductions in the body weight of these same fetuses appeared 3 days after exposure. The effects of radiation on brain and body development were similar for both males and females. (author).

165

A prospective study of 100 roboticallyassisted laparoscopic adrenalectomies  

British Library Electronic Table of Contents (United Kingdom)

We evaluated robotically assisted laparoscopic adrenalectomy (RLA) in a prospective study of 100 consecutive patients (60 women and 40 men) undergoing unilateral adrenalectomy at the University Hospital. The median age was 59 (24?82) years and BMI 27.6 (17.1?40.9) kg/m2. Preoperative diagnoses were Conn?s syndrome 30%, pheochromocytoma 23%, Cushing syndrome 27% and non-functional tumor 20%. The median tumor size was 53 (10?106) mm. The majority of the 7% of the patients who were converted to open surgery were in the early phase after the introduction of the technique. The BMI of the patients who were converted to open surgery was significantly higher, 31.5 (range 25.3?37.8) compared to, 27.5 (range 17.1?40.9) in patients without conversion (P?=?0.047). The median weight of the tumor was 51...

2011-01-01

166

WHAT OLD MEANS TO BONE  

UK PubMed Central (United Kingdom)

The adverse effects of aging of other organs (ovaries at menopause) on the skeleton are well known, but ironically little is known of skeletal aging itself. Evidence indicates that age-related...Full Text Available

2010-06-01

167

Healthy aging and disease: role for telomere biology?  

UK PubMed Central (United Kingdom)

Aging is a biological process that affects most cells, organisms and species. Human aging is associated with increased susceptibility to a variety of chronic diseases, including cardiovascular disease,...Full Text Available

2011-05-01

168

Age Preservation of the Syntactic Processor in Production  

UK PubMed Central (United Kingdom)

Two experiments are reported on the influence of cognitive aging on grammatical choice in language production. In both experiments, participants from two age-groups (young and old) produced...Full Text Available

2003-09-01

169

Fracture Characteristics in a Disposal Pit on Mesita del Buey, Los Alamos National Laboratory  

Energy Technology Data Exchange (ETDEWEB)

The characteristics of fractures in unit 2 of the Tshirege Member of the Bandelier Tuff were documented in Pit 39, a newly excavated 13.7 m deep disposal pit at Material Disposal Area G on Mesita del Buey. The average spacing between fractures is about 1.0 to 1.3 m, the average fracture aperture is about 3 to 5 mm, and the average fracture dip is about 76o to 77o. Fracture spacing and dip in Pit 39 are generally consistent with that reported from other fracture studies on the Pajarito Plateau, although the fracture apertures in Pit 39 are less than reported elsewhere. Measured fracture orientations are strongly affected by biases imparted by the orientations of the pit walls, which, combined with a small data set, make identification of potential preferred orientations dlfflcult. The most prominent ...

1998-12-01

170

Transplacental movement of inorganic lead in early and late gestation in the mouse  

Energy Technology Data Exchange (ETDEWEB)

/sup 203/Pb(NO/sub 3/)/sub 2/ was administered i.v. to pregnant C57BL mice at different stages, from day 8 to day 18 of gestation. The whole animals or excised uteri were subjected to autoradiography or were autopsied for scintillation counting of excised organs. Lead appeared in embryonic and fetal tissues at all stages of gestation. Early (approx. day 8-11) lead was restricted mainly to the embryonic blood, suggesting that free lead was essentially not transferred to the embryo but may have been incorporated in the embryonic hemoglobin when the erythrocytes were formed in the yolk sac placenta (an extraembryonic membrane). From day 12 and later, an uptake was seen in the liver and the cartilaginous skeleton, and from day 14, a strong accumulation was found in calcified bone. This means that the overall fetal concentration increases successively with gestational age of the conceptus. The uptake in fetal liver may be related to the ...

1983-10-01

171

Transplacental movement of inorganic lead in early and late gestation in the mouse  

International Nuclear Information System (INIS)

"2"0"3Pb(NO_3)_2 was administered i.v. to pregnant C57BL mice at different stages, from day 8 to day 18 of gestation. The whole animals or excised uteri were subjected to autoradiography or were autopsied for scintillation counting of excised organs. Lead appeared in embryonic and fetal tissues at all stages of gestation. Early (approx. day 8-11) lead was restricted mainly to the embryonic blood, suggesting that free lead was essentially not transferred to the embryo but may have been incorporated in the embryonic hemoglobin when the erythrocytes were formed in the yolk sac placenta (an extraembryonic membrane). From day 12 and later, an uptake was seen in the liver and the cartilaginous skeleton, and from day 14, a strong accumulation was found in calcified bone. This means that the overall fetal concentration increases successively with gestational age of the conceptus. The uptake in fetal liver may be related to the erythropoiesis taking ...

172

Magnetobiostratigraphy of the continental Paleocene upper Coalspur and Paskapoo formations near Hinton, Alberta  

Energy Technology Data Exchange (ETDEWEB)

A chronology for Paleocene strata of the Hinton area of west-central Alberta was developed from the integration of a magnetostratigraphic and palynostratigraphic study of the upper Coalspur and middle to upper Paskapoo strata in the Coal Valley to Obed Mountain area. The study resulted in the compilation of a complete section of 1100 m of strata with a maximum sediment accumulation rate of 250 m/m.y. Four new informal biostratigraphic units were used to highlight stratigraphically useful bioevents not previously recognized in existing zonations. These strata range in age from magnetochron 29r to 24r and palynozones Wodehouseia spinata Zone, Aquilapollenites reticulatus Subzone through the Pistillipollenite mcgregorii Zone. The 3 intervals with the most rapid changes in the palynoflora were the earliest Paleocene; the transition from the early to middle Paleocene; and in the late Paleocene. Each coincides with critical times in basin ...

2008-06-15

173

High resolution sequence stratigraphy of Scythian-early Anisian continental deposits of east of Paris basin: Applications to gas storage  

Energy Technology Data Exchange (ETDEWEB)

Continental facies of Scythian-early Anisian age (Buntsandstein) of East of the Paris Basin form the underground gas storage reservoir exploited by Gaz de France in the area of Nancy (east of France). An accurate sedimentological study and the application of Genetic Stratigraphy principles lead to the understanding of the deposition of fluvial, which form the reservoirs, and to the reconstruction of their geometries. The subsurface data are calibrated on outcrops. Three types of fluvial systems (braided, sinuous to straight and anastomosed) are defined. A special focus on anastomosed channels permits to differentiate a proximal and a distal facies. Study of laterally continuous outcrops induces recurrent cycles of thickness, velocity and time variations (few tens to hundred ka). These correspond to the highest frequence stratigraphic units, i.e. parasequences or genetic units. Maximum of channel and levee presentation occurs during base-level ...

1995-08-01

174

Vertebroplasty and Kyphoplasty Can Restore Normal Spine Mechanics following Osteoporotic Vertebral Fracture  

UK PubMed Central (United Kingdom)

Osteoporotic vertebral fractures often lead to pain and disability. They can be successfully treated, and possibly prevented, by injecting cement into the vertebral body, a procedure known as vertebroplasty....Full Text Available

175

Ultrasound-Guided Three-In-One Nerve Block for Femur Fractures  

UK PubMed Central (United Kingdom)

Femur fractures typically affect elderly patients with multiple co-morbidities. Pain control can be difficult, requiring intensive nursing and physician care as elderly patients may manifest cardiovascular...Full Text Available

2010-09-01

176

The association between hip fracture and hip osteoarthritis: A case-control study  

UK PubMed Central (United Kingdom)

BackgroundThere have been reports both supporting and refuting an inverse relationship between hip fracture and hip osteoarthritis (OA). We explore this relationship using a case-control...Full Text Available

177

Surgery for hip fractures: Does surgical delay affect outcomes?  

UK PubMed Central (United Kingdom)

Hip fractures are associated with a high rate of mortality and profound temporary and sometimes permanent impairment of quality of life. Current guidelines indicate that surgeons should perform surgery...Full Text Available

2011-01-01

178

Progress in osteoporosis and fracture prevention: focus on postmenopausal women  

UK PubMed Central (United Kingdom)

In the past decade, we have witnessed a revolution in osteoporosis diagnosis and therapeutics. This includes enhanced understanding of basic bone biology, recognizing the severe consequences of fractures...Full Text Available

2009-01-01

179

Perspective on post-menopausal osteoporosis: establishing an interdisciplinary understanding of the sequence of events from the molecular level to whole bone fractures  

UK PubMed Central (United Kingdom)

Current drug treatments for post-menopausal osteoporosis cannot eliminate bone fractures, possibly because the mechanisms responsible for bone loss are not fully understood. Although research within...Full Text Available

2010-03-06

180

Magnetic resonance imaging findings in 46 elbows with a radial head fracture  

UK PubMed Central (United Kingdom)

Background and purposeRadial head fractures are common, and may be associated with other injuries of clinical importance. We present the results of a standard additional MRI scan...Full Text Available

2010-06-01

181

Intraoperative angioembolization in the management of pelvic-fracture related hemodynamic instability  

UK PubMed Central (United Kingdom)

BackgroundThis case series report discusses patients presenting with hemorrhage and hemodymanic compromise due to severe pelvic fractures and undergoing intraoperative angioembolization...Full Text Available

182

Identification and Treatment of Osteoporosis among Elderly Patients with Hip Fractures  

UK PubMed Central (United Kingdom)

OBJECTIVE:To evaluate the profile of osteoporosis treatment among patients hospitalized due to hip fractures at a tertiary-level university hospital. To compare the impact of hospitalization...Full Text Available

2009-12-01

183

Genetic predisposition for femoral neck stress fractures in military conscripts  

UK PubMed Central (United Kingdom)

BackgroundStress fractures are a significant problem among athletes and soldiers and may result in devastating complications or even permanent handicap. Genetic factors may increase...Full Text Available

184

Elastic stable intramedullary nailing of midclavicular fractures in athletes  

UK PubMed Central (United Kingdom)

Background: Intramedullary fixation of midclavicular fractures may be a better option than non-operative treatment for high performance/professional athletes because of the potential reduction...Full Text Available

2003-12-01

185

Dual mobility cup reduces dislocation rate after arthroplasty for femoral neck fracture  

UK PubMed Central (United Kingdom)

BackgroundHip dislocation after arthroplasty for femoral neck fractures remains a serious complication. The aim of our study was to investigate the dislocation rate in acute femoral...Full Text Available

186

Case Reports: Fractures of Threaded Cups: Rare Complications of a Well-established Implant  

UK PubMed Central (United Kingdom)

The use of cementless threaded cups in THA is a well-established treatment. Fractures of the cups are rare complications recorded in individual cases with material defects being discussed as the primary...Full Text Available

2009-03-01

187

Can Deterministic Mechanical Size Effects Contribute to Fracture and Microdamage Accumulation in Trabecular Bone?  

UK PubMed Central (United Kingdom)

Failure of bone under monotonic and cyclic loading is related to the bone mineral density, the quality of the bone matrix and the evolution of microcracks. The theory of linear elastic fracture...Full Text Available

2010-07-21

188

An interdisciplinary intervention for older Taiwanese patients after surgery for hip fracture improves health-related quality of life  

UK PubMed Central (United Kingdom)

BackgroundThe effects of intervention programs on health-related quality of life (HRQOL) of patients with hip fracture have not been well studied. We hypothesized that older patients...Full Text Available

189

Utilizing the right mix of environmental cleanup technologies  

International Nuclear Information System (INIS)

The Savannah River Site (SRS) is a 310-square-mile United States Department of Energy nuclear facility located along the Savannah River near Aiken, South Carolina. During operations, which started in 1951, hazardous substances (chemicals and radionuclides) were released to the environment. The releases occurred as a result of inadvertent spills and waste disposal in unlined pits and basins which was common practice before environmental regulations existed. The hazardous substances have migrated to the vadose zone and groundwater in many areas of the SRS, resulting in 515 waste units that are required by environmental regulations, to undergo characterization and, if needed, remediation. In the initial years of the SRS environmental cleanup program (early 1990's), the focus was to use common technologies (such as pump and treat, air stripping, excavation and removal) that actively and tangibly removed contamination. Exclusive use of these technologies required ...

2007-09-02

190

Thermal and tectonic history of the Ordos Basin, China: Evidence from apatite fission track analysis, vitrinite reflectance, and K-Ar dating  

Energy Technology Data Exchange (ETDEWEB)

Apatite fission track analysis, vitrinite reflectance data, and K-Ar dating of Permian-Carboniferous and Mesozoic core samples have been successfully integrated to reconstruct the thermal and tectonic history of the Ordos basin, China. Apatite fission track ages of Carboniferous-Jurassic sedimentary rocks range between 3 and 137 Ma, and are significantly younger than the stratigraphic ages. Confined fission track lengths demonstrate exclusively mixed length distribution, indicating complex thermal history. The data suggest that the samples must have all experienced higher paleotemperatures in the past. Mean virtinite reflectance values (R{sub o}) of the Triassic rocks range from 0.61 to 1.06%, giving a high coalification gradient of 0.36%/km and suggesting a high paleothermal gradient of 57{degrees}C/km. Permian-Carboniferous rocks have R{sub o} values on the order of 1.0-3.0%, and locally up to 4.0-6.0%. Some high R{sub o} values coincide with ...

1996-07-01

191

The advanced manufacturing science and technology program. FY 95 Annual Report  

Energy Technology Data Exchange (ETDEWEB)

This is the Fiscal Year 1995 Annual Report for the Advanced Manufacturing Science and Technology (AMST) sector of Los Alamos Tactical Goal 6, Industrial Partnering. During this past fiscal year, the AMST project leader formed a committee whose members represented the divisions and program offices with a manufacturing interest to examine the Laboratory`s expertise and needs in manufacturing. From a list of about two hundred interest areas, the committee selected nineteen of the most pressing needs for weapon manufacturing. Based upon Los Alamos mission requirements and the needs of the weapon manufacturing (Advanced Design and Production Technologies (ADaPT)) program plan and the other tactical goals, the committee selected four of the nineteen areas for strategic planning and possible industrial partnering. The areas selected were Casting Technology, Constitutive Modeling, Non-Destructive Testing and Evaluation, and Polymer Aging and Lifetime Prediction. For each ...

1996-03-01

192

Sequence stratigraphy in frontier regions: An example from the Rebi Block, Arafura Sea, Eastern Indonesia  

Energy Technology Data Exchange (ETDEWEB)

The Rebi Block is currently in the early stages of hydrocarbon exploration. The subsurface geology of this area is only known from seismic reflection data. By applying seismic stratigraphy techniques, unconformities and condensed sections were recognized. These discontinuities were dated using paleontological information from the Kulka-1 well, Northwest Shelf of Australia. With these age constraints, seven unconformities and three condensed sections were dated and correlated to the Exxon global sea level curve. The chronostratigraphic charts for the Rebi Block and the Northwest Shelf of Australia have clarified the Mesozoic stratigraphy of the study area. The Exxon global sea level curve has refined the ages determined by conventional paleontological dating. The chart has also helped in predicting source, reservoir and seal potential within a time framework. Prospective stratigraphic traps were those related to the incised ...

1996-12-31

193

New discoveries in prostate cancer pathogenesis  

International Nuclear Information System (INIS)

Background. Through PSA screening the rate of prostate cancers detected at an early stage has increased significantly; thus a decrease in mortality can be expected in the near future. Despite all scientific efforts, however, the molecular mechanisms underlying the development and progression of prostate cancer remain poorly understood. Prostate cancer is a disease of aging men and epidemiological evidence supports a major contribution to its development through diet, lifestyle and environmental factors. Genetic instability is the basic phenomenon of tissue cell cancerisation. This instability can be hereditary or due to mutations and other chromosomal aberrations acquired during life. In recent years a large number of interesting data have been collected which show the relationships between focal atrophy and genetic instability of the prostate epithelia. Atrophy can be the result of prostatitis, ischemia as well as of oxidative stress (diet). ...

194

Magnetic resonance imaging assessment of brain maturation in preterm neonates with punctate white matter lesions  

International Nuclear Information System (INIS)

Early white matter (WM) injury affects brain maturation in preterm infants as revealed by diffusion tensor imaging and volumetric magnetic resonance (MR) imaging at term postmenstrual age (PMA). The aim of the study was to assess quantitatively brain maturation in preterm infants with and without milder forms of WM damage (punctate WM lesions, PWML) using conventional MRI. Brain development was quantitatively assessed using a previously validated scoring system (total maturation score, TMS) which utilizes four parameters (progressive myelination and cortical infolding, progressive involution of glial cell migration bands and germinal matrix tissue). PWML were defined as foci of increased signal on T1-weighted images and decreased signal on T2-weighted images with no evidence of cystic degeneration. A group of 22 preterm infants with PWML at term PMA (PWML group) were compared with 22 matched controls with a normal MR appearance. The two groups ...

2007-02-01

195

Detection of Cholangiocarcinoma with Magnetic Resonance Spectroscopy of Bile in Patients with and without Primary Sclerosing Cholangitis  

International Nuclear Information System (INIS)

Background: Early detection of cholangiocarcinoma (CC) is very difficult, especially in patients with primary sclerosing cholangitis (PSC) who are at increased risk of developing CC. Purpose: To evaluate "1H magnetic resonance spectroscopy ("1H-MRS) of bile as a diagnostic marker for CC in patients with and without PSC. Material and Methods: The institutional review board approved the study, and all patients gave informed consent. Bile from 49 patients was sampled and investigated using "1H-MRS. MR spectra of bile samples from 45 patients (18 female; age range 22-87 years, mean age 57 years) were analyzed both conventionally and using computerized multivariate analysis. Sixteen of the patients had CC, 18 had PSC, and 11 had other benign findings. Results: The spectra of bile from CC patients differed from the benign group in the levels of phosphatidylcholine, bile acids, lipid, and cholesterol. It was possible to ...

2008-10-01

197

Reservoir technology research at the Idaho National Engineering Laboratory  

Energy Technology Data Exchange (ETDEWEB)

The Idaho National Engineering Laboratory (INEL) has been conducting geothermal reservoir research and testing sponsored by the US Department of Energy (DOE) since 1983. The INEL research program is primarily aimed at the development of reservoir engineering techniques for fractured geothermal reservoirs. Numerical methods have been developed which allow the simulation of fluid flow and heat transfer in complex fractured reservoirs. Sensitivity studies have illustrated the importance of incorporating the influence of fractures in reservoir simulations. Related efforts include fracture characterization, geochemical reaction kinetics and field testing.

1987-01-01

198

Hydrothermal coupling in a rough fracture  

CERN Document Server

Heat exchange during laminar flow is studied at the fracture scale on the basis of the Stokes equation. We used a synthetic aperture model (a self-affine model) that has been shown to be a realistic geometrical description of the fracture morphology. We developed a numerical modelling using a finite difference scheme of the hydrodynamic flow and its coupling with an advection/conduction description of the fluid heat. As a first step, temperature within the surrounding rock is supposed to be constant. Influence of the fracture roughness on the heat flux through the wall, is estimated and a thermalization length is shown to emerge. Implications for the Soultz-sous-For\\^{e}ts geothermal project are discussed.

2006-01-01

199

Glass Fragment Hazard from Windows Broken by Airblast  

Science.gov (United States)

... MATHEMATICAL PREDICTION, BODIES, SKIN(ANATOMY), SONIC BOOM, BIOPHYSICS, WOUND BALLISTICS, BONE FRACTURES, SKULL. ...

1980-05-30

200

Fractures in geothermal reservoirs. Special report No. 12  

Energy Technology Data Exchange (ETDEWEB)

Separate abstracts were prepared for thirteen papers. Two papers were abstracted previously for EDB. (MHR)

1982-01-01

201

Femoral neck fracture after irradiation therapy  

International Nuclear Information System (INIS)

Japanese Mar 1999 p. 371-372 Japan Shi, Dequan Yamazaki, Takashi

1999-03-01

202

Evaluation of perfusion of the femoral head after femoral neck fracture using bone scintigraphy  

International Nuclear Information System (INIS)

We treated 13 patients for femoral neck fracture. They consisted of 2 males and 11 females, and were classified according to Garden stage classification; Stage I, 3 cases; Stage II, 2 cases; Stage III, 2 cases; Stage IV, 4 cases. Two trochanteric fracture cases were used by control. We evaluated perfusion of the femoral head after femoral neck fracture using bone scintigraphy, which is considered useful for evaluation of perfusion of the femoral neck before operation. (author)

2002-09-01

203

A Covered Nitinol Stent Fracture in a Patient with a Malignant Esophageal Stricture: A Case Report  

Energy Technology Data Exchange (ETDEWEB)

Self-expanding metallic stent insertion has been widely applied for the palliative treatment of malignant esophageal strictures. Although it is known as an easy, safe, and effective procedure, complications are well known and include things such as stent migration and esophageal stent occlusion caused by tumor in growth. However, metallic stent fractures have been rarely reported in the esophagus, especially for nitinol stents. We report a case of a stent fracture associated with migration in a patient with a malignant esophageal stricture near the gastroesophageal junction. It is highly probable that the stent fracture was due to chemical erosion of the stent caused by gastric juice

2008-11-15

205

The implications of episodic nonequilibrium fracture-matrix flow on site suitability and total system performance  

International Nuclear Information System (INIS)

We apply our work on fracture- and matrix-dominated flow to develop a conceptual model of hydrological flow processes in the unsaturated zone at Yucca Mountain. The possibility of fracture-dominated flow is discussed, and various deductions are made on its impact on natural and total system performance, site characterization activities, and site suitability determination.

1992-04-12

206

Evaluation in femoral neck fracture scintimetry: modes of region of interest selection and influence on results  

Energy Technology Data Exchange (ETDEWEB)

Different sized ROIs within the femoral head and different modes of calculation were used in (/sup 99m/Tc)MDP scintimetry after femoral neck fracture. In preoperative scintimetry, correction for increased trochanteric uptake gave the best discrimination, whereas in postoperative scintimetry the direct ratio fractured/intact femoral head was superior. The change in ROI size had little influence.

1985-04-01

207

Classical fracture mechanics methods  

International Nuclear Information System (INIS)

Comprehensive Structural Integrity is a reference work which covers all activities involved in the assurance of structural integrity. It provides engineers and scientists with an unparalleled depth of knowledge in the disciplines involved. The new online Volume 11 is dedicated to the mechanical characteristics of materials. This paper contains the chapter 11.02 of this volume and is structured as follows: Test techniques; Analysis; Fracture behavior; Fracture toughness tests for nonmetals.

208

Cleaning Aged EPDM Rubber Roofing Membrane Material for ...  

Science.gov (United States)

... 5. The results of the bond strength measurements were compared to the surface cleanness of the aged EPDM as determined by the specified ...

1992-08-01

209

Lithofacial characteristics and geological structure of the Mesozoic to Cenozoic sediments of the Zapadno Rakushechniy Sea site  

Energy Technology Data Exchange (ETDEWEB)

Seismic exploration is used to identify the Zapadno Rakushechniy Sea uplift. It is promising with respect to prospecting for oil and gas deposits as a result of its proximity to the Severo Rakushechniy deposit with commercial oil and gas presence in the Triassic sediments. Structural prospecting wells are drilled at the Zapadno Rakushechnyy Sea site which open sediment from the Neogene to the upper Triassic. The Triassic sediments are represented by a thick terrigeneous to carbonate series washed out to a varying degree and covered by Jurassic sediments. A comparison of the lithofacial composition of the Triassic sediments shows that the thickness and lithological composition o the Triassic rocks varies by site, while the sediments of the upper Triassic are sharply reduced in thickness to the southsouthwest. The older are the sediments of the Indskiy stage of the lower Triassic. The isolated stages of the lower, middle and upper Jurassic suffer a reduction in thickness towards the ...

1984-01-01

210

Study on fracture behaviour of Al?15%Mg2Si metal matrix composite with and without beryllium additions  

British Library Electronic Table of Contents (United Kingdom)

In this study, the influence of Beryllium (Be) content on the fracture behaviour of Al?15%Mg2Si composite was investigated. The results showed an increase in mechanical properties with increasing of Be content. The stress?strain curves of samples showed a same category of serrations reflecting non-uniform deformation. Scanning electron microscopy was employed to examine the crack nucleation and fracture model. The results indicate that Al?15%Mg2Si composite shows different behaviours of crack initiation and fracture for samples with and without Be. Differences observed in the fracture behaviour were attributed to microstructural changes as well as morphological aspects of primary Mg2Si particles.

2011-01-01

211

Stresses and fractures in the Frontier Formation, Green River Basin, predicted from basin-margin tectonic element interactions  

Energy Technology Data Exchange (ETDEWEB)

Natural fractures and in situ stresses commonly dictate subsurface reservoir permeability and permeability anisotropy, as well as the effectiveness of stimulation techniques in low-permeability, natural gas reservoirs. This paper offers an initial prediction for the orientations of the fracture and stress systems in the tight gas reservoirs of the Frontier Formation, in the Green River basin of southwestern Wyoming. It builds on a previous report that addressed fractures and stresses in the western part of the basin and on ideas developed for the rest of the basin, using the principle that thrust faults are capable of affecting the stress magnitudes and orientations in little-deformed strata several hundreds of kilometers in front of a thrust. The prediction of subsurface stresses and natural fracture orientations is an undertaking that requires the willingness to revise models as definitive data are ...

1996-01-01

212

Sequential scintimetry after femoral neck fracture. Methodologic aspects and prediction of healing complications  

Energy Technology Data Exchange (ETDEWEB)

Forty-five patients with recent cervical hip fractures were included in a prospective, clinical, radiographic and sequential scintimetric study. Striking changes in radionuclide uptake over the entire hip region on the fracture side were found during the first 5 postoperative months. Fractures that healed without complications showed the highest relative femoral head uptake at 1 week and a peak value at 6 weeks, followed by a gradual decline at the subsequent examinations. Fractures with complications (redisplacement, nonunion, or late segmental collapse) showed a lower initial uptake and a more gradual increase and only a slight tendency towards increased uptake after 3 months. The accuracy in predicting nonunion with scintimetric examination alone is high both at 1 and at 6 weeks, and the accuracy is almost equally high with combined scintimetric, radiographic, and clinical assessment 3-5 months ...

1987-01-01

213

Microstructure and fracture toughness of hot pressed zirconia-toughened sialon  

International Nuclear Information System (INIS)

Zirconia-toughened sialon composites have been fabricated using conventional hot-pressing techniques. The fracture toughness and microstructure were determined for CeO_2- and Y_2O_3-stabilized ZrO_2 additives and also as a function of volume percent ZrO_2. The Yttria system showed a linear increase in fracture toughness with increasing volume fraction zirconia content while the ceria-stabilized system exhibited a peak in fracture toughness at 20 vol% ZrO_2 content. The fracture toughness at 800 C was measured and correlated with the microstructure. High-temperature stability was determined and it was found that the deleterious nitride phases of zirconium could be precluded from the microstructure.

214

Method of constraint loss correction of CTOD fracture toughness for fracture assessment of steel components  

British Library Electronic Table of Contents (United Kingdom)

This paper presents a procedure for transferring the CTOD fracture toughness obtained from laboratory specimens to an equivalent CTOD for structural components, taking constraint loss into account. The Weibull stress criterion is applied to correct the CTOD for constraint loss, which leads to an equivalent CTOD ratio, b, defined as b=d/dWP, where d and dWP are CTODs of the standard fracture toughness specimen and the structural component, respectively, at the same level of the Weibull stress. The CTOD ratio b is intended to apply to the fracture assessment of ferritic steel components to stress levels beyond small-scale yielding. Nomographs are given to determine the b-value as a function of the crack type and size in the component, the yield-to-tensile ratio of the material and the Weibul...

2006-01-01

215

Measurement of dynamic fracture toughness and failure behavior for explosive mock materials  

British Library Electronic Table of Contents (United Kingdom)

In this work, a pre-cracked semi-circular shaped explosive simulant was loaded using a split Hopkinson pressure bar (SHPB). A high-speed camera was used to capture the deformation and fracture process of the specimen in situ. The digital images were processed using the digital image correlation (DIC) method. Next, full displacement and strain fields were obtained. The displacement vector field shows that the specimen fractured under tensile stress action. The strain field can be used to predict the crack propagation. Results show that the method of combined DIC and SHPB is effective to study the dynamic deformation and fracture behavior of explosive simulants. In addition, the specimen was loaded using a drop weight. The fracture toughness of the specimen was preliminary measured.

2011-01-01

216

Fracture mechanics: proceedings of the 12th national symposium on fracture mechanics  

Energy Technology Data Exchange (ETDEWEB)

The conference proceedings contains 30 papers of which five are abstracted separately. The subjects covered include fatigue crack growth in aircraft materials, fractographic measurements, fatigue cracks in nylon 66 blends, cyclic inelastic deformation aspects, prestressing, tensile cracks in creeping solids, creep-crack-growth in 304 stainless steel, high-temperature fatigue, parallel impact loading, numerical fracture dynamic code, J-resistance curves, specimen geometry effects, reactor piping systems, temperature dependence of fracture toughness, small-scale yielding, compact specimens, power hardening materials, semi-empirical fracture analyses, pipeline girth welds, wrought steels, and A36 bridge steels.

1980-01-01

217

Fracture behavior under dynamic biaxial stress on magnesium alloy  

Energy Technology Data Exchange (ETDEWEB)

We conduct the static and dynamic loading fracture experiments on magnesium alloy (AZ31B) under the equitable and inequitable biaxial stress. We process specimens as cross type with cracks. There are different kinds of cracks defined by their crack angles. By using a hydraulic high-speed biaxial experiment machine, we put the equitable and inequitable stresses on the specimen. We analyze results using the caustic method. The experiments reveal a few important results. There is negative correlation between the fracture toughness value and the plate thickness in the magnesium alloy sheet specimen. The fracture toughness value decrease in the case the crack has the angle different from the loading direction. The fracture toughness value decreases significantly under the inequitable biaxial stress. (orig.)

2004-07-01

218

Coupled mechanical and chemical processes in engineered geothermal reservoirs with dynamic permeability  

British Library Electronic Table of Contents (United Kingdom)

A model is developed to represent mechanical strain, stress-enhanced dissolution, and shear dilation as innately hysteretic and interlinked processes in rough contacting fractures. The model is incorporated into a numerical simulator designed to examine permeability change and thermal exchange in chemically active and deformable fractured reservoirs. A candidate engineered geothermal reservoir system (EGS) is targeted. The mechanistic model is able to distinguish differences between the evolution of fluid transmission characteristics of (1) small scale, closely spaced fractures, and (2) large-scale, more widely spaced fractures. Alternate realizations of fracture frequency and scale, exhibiting identical initial bulk permeability, lead to significantly different conclusions regarding perme...

2010-01-01

219

Computed tomography of the acetabular fractures  

Energy Technology Data Exchange (ETDEWEB)

In a retrospective study of 21 patients, in whom the acetabular fractures were suspected on initial radiographs, we compared and analysed the computed tomographic findings and plain radiographic findings. The results were as follow: 1. In patients with multiple trauma, no further change in position was required during CT examinations. 2. CT showed intraarticular loose bodies, which were invisible on plain radiographs. 3. CT was useful in detecting the fractures of acetabular rims, medial wall of acetabulum, and femoral head. 4. CT permitted better evaluation of shape, extent, and degree of separation of fracture fragments. 5. CT was helpful in detecting the associated fractures and soft tissue injuries. 6. CT also demonstrated the adequacy of reduction, the position of metallic fixation devices, and the presence or absence of remaining intraarticular osseous fragments after surgery.

1986-04-15

220

Comparison of skeletal and bone marrow radionuclide scintimetry of femoral neck fracture  

Energy Technology Data Exchange (ETDEWEB)

Twenty-six patients with late complications following femoral neck fracture were examined with both skeletal and bone marrow radionuclide scintimetry. There was no correlation between the methods with respect to the quantitative assessment of femoral head vascularity based on different uptake ratios comparing the fractured and the intact side. Skeletal scintimetry always had good image quality and permitted reliable differentation between nonunion of the fracture and late segmental collapse, in contrast to bone marrow scintimetry which gave poor image quality. Skeletal scintimetry thus seems superior to bone marrow scintimetry for assessment and differential diagnosis of late complications following femoral neck fracture. It is emphasized that the physiological mechanisms for radionuclide uptake must be taken into account when comparing scintimetric studies using different tracers.

1984-01-01

221

Comparison of skeletal and bone marrow radionuclide scintimetry of femoral neck fracture  

International Nuclear Information System (INIS)

Twenty-six patients with late complications following femoral neck fracture were examined with both skeletal and bone marrow radionuclide scintimetry. There was no correlation between the methods with respect to the quantitative assessment of femoral head vascularity based on different uptake ratios comparing the fractured and the intact side. Skeletal scintimetry always had good image quality and permitted reliable differentation between nonunion of the fracture and late segmental collapse, in contrast to bone marrow scintimetry which gave poor image quality. Skeletal scintimetry thus seems superior to bone marrow scintimetry for assessment and differential diagnosis of late complications following femoral neck fracture. It is emphasized that the physiological mechanisms for radionuclide uptake must be taken into account when comparing scintimetric studies using different tracers. (author).

222

Flow regime transfer conditions for two-phase flow in a fracture  

Energy Technology Data Exchange (ETDEWEB)

Between 25 and 30 percent of total known petroleum reserves are contained within oil-laden fractured reservoirs where the dominant flow path is through the fractures. Economic oil recoveries from fractured reservoirs depend on a better understanding of the flow in fractures and networks of fractures. However, the flow of heavy oil and water, and particularly the flow regime map for two-phase immiscible flow has received less attention in contrast with gas-liquid flow in fractures. This paper discussed the use of flow pattern observations in a Hele-Shaw cell to generate two-phase flow regime maps. The paper investigated the effect of fracture gap and fluid viscosities on flow regimes. A correlation based on different flow and fracture properties was developed to define flow transition conditions between flow regimes. The ...

2010-07-01

223

Genes related to the very early stage of ConA-induced fulminant hepatitis: a gene-chip-based study in a mouse model  

UK PubMed Central (United Kingdom)

BackgroundDue to the high morbidity and mortality of fulminant hepatitis, early diagnosis followed by early effective treatment is the key for prognosis improvement. So far, little...Full Text Available

224

Stable isotopes of authigenic minerals in variably-saturated fractured tuff  

Energy Technology Data Exchange (ETDEWEB)

Identifying stable isotope variation and mineralogical changes in fractured rock may help establish the history of climatic and geomorphological processes that might affect the isolation properties of a waste repository site. This study examines the use of the stable isotope ratios of oxygen ({sup 18}O/{sup 16}O) and carbon ({sup 13}C/{sup 12}C) in authigenic minerals as hydrogeochemical tools tracing low-temperature rock-water interaction in variably-saturated fractured stuff. Isotopic compositions of fracture-filling and rock matrix minerals in the Apache Leap tuff, near Superior, Arizona were concordant with geothermal temperatures and in equilibrium with water isotopically similar to present-day meteoric water and groundwater. Oxygen and carbon isotope ratios of fracture-filling, in unsaturated fractured tuff, displayed an isotopic gradient believed to result from near-surface ...

1988-11-01

225

Estimates of the width of the wetting zone along a fracture subjected to an episodic infiltration event in variably saturated, densely welded tuff  

Energy Technology Data Exchange (ETDEWEB)

A central issue to be addressed within the Nevada Nuclear Waste Storage Investigations (NNWSI) is the role which fractures will play as the variably saturated, fractured rock mass surrounding the waste package responds to heating, cooling, and episodic infiltration events. Understanding the role of fractures during such events will, in part, depend on our ability to make geophysical measurements of perturbations in the moisture distribution in the vicinity of fractures. In this study we first examine the details of the perturbation in the moisture distribution in and around a fracture subjected to an episodic infiltration event, and then integrate that behavior over the scale at which moisture measurements are likely to be made during the Engineered Barrier Design Test of the NNWSI project. To model this system we use the TOUGH hydrothermal code and fracture and ...

1988-05-31

226

The early phase change Gene in Maize  

UK PubMed Central (United Kingdom)

Recessive mutations of the early phase change (epc) gene in maize affect several aspects of plant development. These mutations were identified initially because of...Full Text Available

2002-01-01

227

Effect of grain boundary microstructures of brittle fracture in polycrystalline molybdenum  

Energy Technology Data Exchange (ETDEWEB)

Superplasticity can be generally achieved by grain boundary sliding (GBS). The GBS in polycrystalline materials sometimes accompanies with intergranular fracture because of stress concentrations at triple points and/or GB irregularities. To develop the superplastic flow, it is necessary to suppress the intergranular cracking. In the present study, therefore, polycrystalline molybdenum with distinct GB microstructures, such as grain boundary character distribution (GBCD), has been employed to clarify the relationship between fracture behaviour and GB microstructures. Microstructures were analyzed using a FE-SEM/EBSP/OIM system prior to 4-points bending tests at 77K, thereafter, crack propagation was observed. The main results obtained are as follows. Stress fluctuations on stress - strain curves were observed for specimens with random oriented grains, whereas such behaviour rarely occurred for ones with textured grains. Difference in the ...

1999-07-01

228

Clinically silent heterotaxy with polysplenia syndrome and IVC azygous continuation draining to SVC: CT findings. Case report  

International Nuclear Information System (INIS)

Patients with heterotaxy syndrome often have complex cardiac and extracardiac anomalies requiring further detailed diagnostic evaluation. They often present severe cardiac failure early in life. Newer radiological modalities in the form of spiral computed tomography (CT) and three-dimensional reconstruction of spiral CT allow clear definition of the anatomy of these anomalies. A 59-year-old woman was diagnosed with polysplenia and multiple anomalies in an abdominal ultrasonography (US) during a control medical examination due to a trivial dietary mistake. She was then referred to our institution for further examination of these anomalies and an additional thoraco-abdominal computed tomography (CT) examination. The patient was totally asymptomatic at the time of admission. There was no significant past history and no abnormal laboratory data. We performed abdominal, pelvic and thoracic CT examinations using Somatom Siemens Emotion scanner. Non-enhanced sections were ...

2007-01-01

229

THE CHEMICAL EVOLUTION OF THE URSA MINOR DWARF SPHEROIDAL GALAXY  

International Nuclear Information System (INIS)

We present an abundance analysis based on high-resolution spectra of 10 stars selected to span the full range in metallicity in the Ursa Minor (UMi) dwarf spheroidal (dSph) galaxy. We find that [Fe/H] for the sample stars ranges from -1.35 to -3.10 dex. Combining our sample with previously published work for a total of 16 luminous UMi giants, we establish the trends of abundance ratios [X/Fe] as functions of [Fe/H] for 15 elements. In key cases, particularly for the #alpha#-elements, these trends resemble those for stars in the outer part of the Galactic halo, especially at the lowest metallicities probed. The neutron-capture elements show an r-process distribution over the full range of Fe metallicity reached in this dSph galaxy. This suggests that the duration of star formation in the UMi dSph was shorter than in other dSph galaxies. The derived ages for a larger sample of UMi stars with more uncertain metallicities also suggest a population dominated by ...

2010-08-10

230

Quantitative CT assessment of proximal femoral bone density. An experimental study concerning its correlation to breaking load for femoral neck fractures  

International Nuclear Information System (INIS)

Purpose: In an experimental study, the correlation between the trabecular bone density of the different regions of the proximal femur and the fracture load in the setting of femoral neck fractures was examined. Methods: The bone mineral density 41 random proximal human femora was estimated by single-energy quanitative CT (SE-QCT). The trabecular bone density was measured at the greatest possible extracortical volume at midcapital, midneck and intertrochanteric level and in the 1 cm"3 volumes of the centres of these regions in a standardised 10 mm thick slice in the middle of the femoral neck axis (in mg/ml Ca-hydroxyl apatite). The proximal femora were then isolated and mounted on a compression/bending device under two-legged stand conditions and loaded up to the point when a femoral neck fracture occurred. Results: Statistical analysis revealed a linear correlation between the trabecular bone density and the ...

231

Direct digital radiography versus storage phosphor radiography in the detection of wrist fractures  

Energy Technology Data Exchange (ETDEWEB)

AIM: To define the value of digital radiography with a clinical flat panel detector system for evaluation of wrist fractures in comparison with state of the art storage phosphor radiography. MATERIAL AND METHODS: Hard copy images of 26 fractured wrist specimens were acquired with the same exposure dose on a state of the art storage phosphor radiography system and a clinical flat panel detector. Image features like cortical bone surface, trabecular bone, soft tissues and fracture delineation were independently analysed by 4 observers using a standardised protocol. Image quality ratings were evaluated with an analysis of variance (ANOVA). RESULTS: Flat panel detector radiographs were rated superior with respect to cortical and trabecular bone representation as well as fracture evaluation, while storage phosphor radiographs produced better soft tissue detail. CONCLUSION: In some of the observed image ...

2002-04-01

232

Direct digital radiography versus storage phosphor radiography in the detection of wrist fractures  

International Nuclear Information System (INIS)

AIM: To define the value of digital radiography with a clinical flat panel detector system for evaluation of wrist fractures in comparison with state of the art storage phosphor radiography. MATERIAL AND METHODS: Hard copy images of 26 fractured wrist specimens were acquired with the same exposure dose on a state of the art storage phosphor radiography system and a clinical flat panel detector. Image features like cortical bone surface, trabecular bone, soft tissues and fracture delineation were independently analysed by 4 observers using a standardised protocol. Image quality ratings were evaluated with an analysis of variance (ANOVA). RESULTS: Flat panel detector radiographs were rated superior with respect to cortical and trabecular bone representation as well as fracture evaluation, while storage phosphor radiographs produced better soft tissue detail. CONCLUSION: In some of the observed image ...

2002-04-01

238

Creation of the BioBank, Early Detection and Discovery Biomarkers  

Science.gov (United States)

Pancreatic Cancer; Head and Neck Cancer; Breast Cancer

2011-04-03

239

In-vitro radioimmunoassay of prostate specific antigen (PSA) for the screening and management of prostate cancer in Lebanon  

International Nuclear Information System (INIS)

Full text: Immunoassays for prostate-specific antigen (PSA) are used to detect early-stage prostate cancer, monitor disease progress, and evaluate therapeutic response. At least two forms of PSA, free PSA (F-PSA) and PSA complexed to alpha-1 anti-chymotrypsin (PSA-ACT) are detected by commercial PSA assays. The fraction of F-PSA is shown to be smaller in patients with untreated prostate cancer than in patients with benign prostate hyperplasia (BPH). Thus, combined measurements of both total and free PSA are used for a better discrimination between BPH and prostate cancer. Detection of PSA for screening of prostate cancer has been a subject of debate for many years. The reason of this debate is mainly because screening for prostate cancer is not cost-effective, as was shown by studies undertaken in Europe and United States. In Lebanon, no previous programs of screening for prostate cancer were done and so the incidence of this cancer is not known. Recently, the ...

2004-01-01

240

The use of maxillomandibular fixation screws with essig wiring in the treatment of symphyseal fracture of deep bite patients  

British Library Electronic Table of Contents (United Kingdom)

Today, the use of the arch bars in the treatment of mandibular fractures is common [1]. But it has complications such as damaged teeth, periodontal tissue [2], risk of blood transmitted disease [3] and premature contact with maxillary incisor teeth in anterior deep bite occlusion. Many techniques are used for resolving these problems. In this paper, we describe the technique of using Maxillo-Mandibular Fixation Screws (MMFS) with essig wiring of anterior mandibular teeth in the management of symphyseal fracture of deep bite patients.

2009-01-01

241

Strength and toughness of a metastable beta-titanium alloy as influenced by strain rate variations  

International Nuclear Information System (INIS)

Strain rate effects for the high strength, metastable beta-titanium alloy Ti-8Mo-8V-2Fe-3Al are assessed in terms of tensile and fracture toughness behavior. It is shown that as the strain rate increases the yield strength, ultimate tensile strength, and ductility also increase. As a result of the decrease in the amount of intergranular fracture as the strain rate is increased, the dynamic fracture toughness values K/sub Id/ are greater than those obtained under static conditions as given by K/sub Q/.

242

A T-2 translational research perspective on interventions to improve post-fracture osteoporosis care  

British Library Electronic Table of Contents (United Kingdom)

The objectives of this paper are to: quickly outline the extent of the care gap in osteoporosis; define T-2 (knowledge) translation and its relationship to quality improvement; discuss the barriers to best practice in osteoporosis care after a fracture; convey the importance of rigor in design and evaluation of translational interventions by drawing upon examples from the broader literature; describe in some detail a series of post-fracture intervention trials conducted in Alberta, Canada; and make some conclusions specifically about osteoporosis interventions and more generally about T-2 translational research.

2011-01-01

243

Variable Pathogenicity Determines Individual Lifespan in Caenorhabditis elegans  

UK PubMed Central (United Kingdom)

A common property of aging in all animals is that chronologically and genetically identical individuals age at different rates. To unveil mechanisms that influence aging variability, we identified markers...Full Text Available

2011-04-01

244

The Human Ageing Genomic Resources: online databases and tools for biogerontologists  

UK PubMed Central (United Kingdom)

SummaryAgeing is a complex, challenging phenomenon that will require multiple, interdisciplinary approaches to unravel its puzzles. To assist basic research on ageing, we developed...Full Text Available

2009-02-01

245

Rethinking the evolutionary theory of aging: Transfers, not births, shape senescence in social species  

UK PubMed Central (United Kingdom)

The classic evolutionary theory of aging explains why mortality rises with age: as individuals grow older, less lifetime fertility remains, so continued survival contributes less to reproductive fitness....Full Text Available

2003-08-05

246

Reduced thermal sensitivity and Nav1.8 and TRPV1 channel expression in sensory neurons of aged mice  

UK PubMed Central (United Kingdom)

Sensory neurons in aging mammals undergo changes in anatomy, physiology and gene expression that correlate with reduced sensory perception. In this study we compared young and aged mice to identify...Full Text Available

2006-06-01

247

Comparative and alternative approaches and novel animal models for aging research  

UK PubMed Central (United Kingdom)

This special issue of AGE showcases powerful alternative or unconventional approaches to basic aging research, including the use of exceptionally long-lived animal model species and...Full Text Available

2008-09-01

248

Changes in Androgen Receptor, Estrogen Receptor alpha, and Sexual Behavior with Aging and Testosterone in Male Rats1  

UK PubMed Central (United Kingdom)

Reproductive aging in males is characterized by a diminution in sexual behavior beginning in middle age. We investigated the relationships among testosterone, androgen receptor (AR) and estrogen...Full Text Available

2010-07-01

249

Aging alters the expression of neurotransmission-regulating proteins in the hippocampal synaptoproteome  

UK PubMed Central (United Kingdom)

Decreased cognitive performance reduces independence and quality of life for aging individuals. Healthy brain aging does not involve significant neuronal loss, but little is known about the...Full Text Available

2010-06-01

250

Ageing in Drosophila: The role of the insulin/Igf and TOR signalling network  

UK PubMed Central (United Kingdom)

A remarkable discovery of recent years is that, despite the complexity of ageing, simple genetic interventions can increase lifespan and improve health during ageing in laboratory animals. The pathways...Full Text Available

2011-05-01

251

Advanced glycation end-products in senile diabetic and non-diabetic patients with cardiovascular complications  

UK PubMed Central (United Kingdom)

Advanced glycation end products (AGEs) have been reported to contribute to aging and cardiovascular complications. In the present study, the immunoreactivity of AGEs in human serum samples of healthy...Full Text Available

2008-12-01

252

AGEs Secreted by Bacteria Are Involved in the Inflammatory Response  

UK PubMed Central (United Kingdom)

Advanced Glycated End Products (AGEs) are formed by non-enzymatic protein glycation and are implicated in several physiological aspects including cell aging and diseases. Recent data indicate that bacteria...Full Text Available

253

The Combined Influence of Molecular Weight and Temperature on the ...  

Science.gov (United States)

[12] Kusy, R. P. and Turner, D. T.: Influence of molecular-weight ofpoly(methyl methacrylate)on fracture morphology in notched tension, Polymer. ...

254

Surgeons' beliefs and perceptions about removal of orthopaedic implants  

UK PubMed Central (United Kingdom)

BackgroundThe routine removal of orthopaedic fixation devices after fracture healing remains an issue of debate. There are no evidence-based guidelines on this matter, and little...Full Text Available

258

Mechanical properties and fracture behavior of #alpha# particle irradiated type 316 stainless steel at high temperature  

International Nuclear Information System (INIS)

The effect of helium on the mechanical properties and fracture behaviors of a type 316 austenitic steel is presented. Helium implantation was performed by 30-MeV #alpha#-particle injection on very small, thin specimens, using a cyclotron accelerator. Average helium content in the He-deposited region was 50 to 2000 appm He. These specimens showed the transition of fracture mode from transgranular to intergranular fracture in elevated temperature tests. The transition temperature decreased with increase in the amount of implanted helium. For example, in the case of 2000 appm and 500 appm He implantation, the transition temperatures were between 773 and 873 K and 873 and 973 K, respectively. (orig.).

259

MR findings in cases of suspected impacted fracture of the femoral neck  

Energy Technology Data Exchange (ETDEWEB)

Purpose: To evaluate MR imaging of the hip in patients with a clinically suspected impacted fracture of the femoral neck in cases where conventional plain films show negative or equivocal findings. Material and Methods: Twenty-seven such patients were prospectively examined by MR imaging with a 1.0 T unit, within 24 hours of admittance to hospital. A coronal T1-weighted turbo spin-echo sequence (n=27), and a coronal STIR sequence (n=25) or a coronal T2-weighted turbo spin-echo fast saturation sequence (n=2) were used. The evaluations were made by 2 radiologists with experience in musculoskeletal radiology. Results: There were 6 patients with a petrochanteric fracture, 2 without and 4 with slight displacement. Five patients had an impacted fracture of the femoral neck, and 3 had a fracture of the superior pubic bone. Of 2 patients with advanced arthrosis, i had an impacted femoral neck ...

1997-09-01

260

Hydraulic Fracture Stimulation Treatments at East Mesa, Well 58-30; Geothermal Reservoir Well Stimulation Program; Experiment 3 and 4  

Energy Technology Data Exchange (ETDEWEB)

The tests reported were part of the DOE Geothermal Reservoir Well Stimulation Program. This East Mesa (Imperial Valley, CA) well was successfully stimulated with two fracture treatments, a dendritic fracture and a planar fracture. The natural flow production of the well increased 114 percent, to 197,900 lb/hr. These tests were among the few successful attempts of this program to increase flow from geothermal production wells. The general belief is that these tests worked OK primarily because the formation was sedimentary rock (similar to rock in most oil and gas wells that have been stimulated successfully. Similar tests in geothermal hard rock reservoirs did not work very well. (DJE 2005)

1982-02-01

261

Facet joint injuries in acute cervical spine trauma : evaluation with CT and MRI  

Energy Technology Data Exchange (ETDEWEB)

To evaluate injury patterns of facet joints and associated soft tissue injuries in patients with acute traumatic cervical facet joint injuries. From among patients with cervical spine trauma, 27 with facet joint injuries, as seen on CT and MRI, were chosen for this study. CT scans were analyzed with regard to the location of facet joint injury, the presence or absence of facet dislocation or fracture, and other associated fractures. MR images were analyzed with regard to ligament injury, intervertebral disc injury, intervertebral disc herniation, and spinal cord injury. The most common location of facet joint injury was C6-7 level(n=10), followed by C5-6(n=8). Among these 27 patients with facet joint injuries, 12(44%) had bilateral injuries and 15(56%) unilateral injuries. Facet fractures were present in 17 cases(63%) and the fracture of inferior facet was more frequent than superior. Patterns of ...

1999-05-01

262

FATIGUE OF BIOMATERIALS: HARD TISSUES  

UK PubMed Central (United Kingdom)

The fatigue and fracture behavior of hard tissues are topics of considerable interest today. This special group of organic materials comprises the highly mineralized and load-bearing tissues...Full Text Available

2010-09-01

263

Estimating hip fracture risk from digital x-ray image data  

International Nuclear Information System (INIS)

The authors propose a method for determining the risk of femoral neck fracture in osteoporotic patients that is not based on densitometric techniques. The method is based on a structural analysis performed by a computer on data taken from a single digital anteroposterior projection of the hip. From the image, the effective cross-sectional area and cross-sectional moment of inertia are computed from attenuation principles. Together with other geometric measurements, these data are used in an engineering analysis to compute the yield strength of the proximal femur, under stress applied through the acetabulum in a one-legged stance. An index of fracture risk based on the ratio of estimated yield strength to body weight is proposed. Ultimately it is expected that this work will allow the clinician to estimate hip fracture risk in osteoporotic patient using widely available existing technology, a goal which has eluded bone ...

265

Do Higher Hospital-wide Nurse Staffing Levels Reduce In-hospital Mortality in Elderly Patients with Hip Fractures: A Pilot Study  

British Library Electronic Table of Contents (United Kingdom)

Background There is increasing recognition that lower nurse staffing levels are associated with higher morbidity and mortality among medical and surgical patients. The degree to which this applies to elderly patients with hip fractures is unclear. Questions/purposes We conducted a pilot study using administrative data as an initial step in investigating the relationship between nurse staffing levels and in-hospital mortality among elderly patients with hip fractures. Patients and Methods We retrospectively reviewed administrative data for 13,343 patients 65?years or older with a primary diagnosis of hip fracture admitted to 39 Michigan hospitals between 2003 and 2006. We used logistic regression to calculate the change in predicted probability of in-hospital death conferred by differences ...

2011-01-01

266

Do Estrogen and Alendronate Improve Metaphyseal Fracture Healing When Applied as Osteoporosis Prophylaxis?  

British Library Electronic Table of Contents (United Kingdom)

Osteoporosis is accompanied by predominantly metaphyseal fractures with a delayed and qualitatively reduced healing process. This study addressed the question of whether fracture healing in the context of osteoporosis prophylaxis is improved with estrogen (E) or alendronate (ALN). Thirty-six ovariectomized and 12 sham-operated 12-week-old rats received soy-free (osteoporotic C, sham), E-, or ALN- supplemented diets. After 10?weeks, a metaphyseal tibia osteotomy and standardized T-plate fixation were performed. After a 5-week healing process, the fracture callus was evaluated qualitatively by biomechanical bending test and quantitatively in microradiographic sections. The time course of callus formation was examined using fluorochrome-labeled histological sections. Administration of E impro...

2010-01-01

267

Development of Point Arguello field, offshore California  

Energy Technology Data Exchange (ETDEWEB)

Development drilling from Chevron-operated Platform Hermosa, located on OCS-P 0316 of the Point Arguello field, began on January 30, 1987. To date, seven development wells have been drilled in to the northwest-southeast-trending, doubly plunging anticlinal structure. The results from drilling have confirmed the presence of intense folding and fracturing in the targeted Monterey Formation. Over 700 ft of conventional core were recovered from the B-2 well in the lower Sisquoc and Monterey Formations. Analysis of the core material has yielded important information on lithologic variations and fracture patterns in the productive Monterey Formation. Initial results of core studies, DST data, and wireline studies indicate a correlation between rock type and fracturing. Fracture trends and directional permeability suggested by drill-stem testing may affect future drilling patterns in the field.

1988-03-01

268

DARPA - Advanced Composite Materials Annual Presentation ...  

Science.gov (United States)

... 66. BV Sankar and MA Pinheiro, "An Offset Beam Finite Element for Fracture Analysis of Delaminations," AIAA Paper Number 90-1024-CP, 31st ...

1992-11-20

269

Crack tip opening angle measurement through a girth weld in an X100 steel pipeline section  

British Library Electronic Table of Contents (United Kingdom)

ABSTRACT Crack tip opening angle (CTOA) is becoming one of the most accepted methods for characterizing fully plastic fracture. It provides a measure of the resistance to fracture for a material in cases where there is a large degree of stable-tearing crack extension during the fracture process. Our current pipeline research uses the CTOA test as an alternative, or addition, to the CTOD (crack tip opening displacement) and the fracture energy characterization provided by the J-integral approach. A test technique was developed for measurement of CTOA that uses a modified double cantilever beam (MDCB) specimen. A digital camera and image analysis software were used to record the progression of the crack tip and to estimate the CTOA. In this article, CTOA data on crack growth orientations per...

2008-01-01

270

Chylothorax  

UK PubMed Central (United Kingdom)

During a high speed road traffic accident, a 26-year-old man suffered multiple fractures of his thoracic vertebrae and bilateral pneumothoraces. The day after admission and commencement of nasogastric...Full Text Available

271

Behavior of particle-filled polymer composite under static and dynamic loading  

British Library Electronic Table of Contents (United Kingdom)

Experimental results of quasi-static and dynamic fracture of particle-filled polymer composite (PFPCM) "ALTUGLAS EI CH25" with a matrix of polymethylmethacrylate (PMMA) are reported in this paper. PMMA matrix is filled with rubber particles, as result a shock-resistant transparent composite is produced. The main task was to investigate experimentally and theoretically the fracture toughness of this composite under static and dynamic loading. A high-rate loading has been created by impulse magnetic field. Analysis of fracture process and its relation with the load parameters and material microstructure have been established. Application of the original testing method enabled determination of fracture toughness at very short loading times and comparison of the results with material dynamic p...

2008-01-01

272

Application of constraint-sensitive fracture mechanics to the assessment of girth weld integrity  

Energy Technology Data Exchange (ETDEWEB)

The dominant fracture parameters used in fracture mechanics analyses of pipelines are related to the asymptotic crack-tip stress and strain fields at the crack tip. This paper reviewed new developments in constraint-sensitive fracture mechanics for the assessment of pipeline girth weld integrity. Constraint theories and experimental studies were evaluated. Constraint models included brittle fracture models and ductile fracture models. Constraint models for brittle fracture are based on weakest link statistics and Weibull distribution. Specifically designed experimental tests are often necessary to derive the damage parameters of ductile fracture models. Experimental test data must then be calibrated with finite element analyses (FEA) to ensure that the correct damage parameters are chosen. The effects of specimen geometry and loading ...

2004-07-01

273

Multiple stress aging of solid-dielectric extruded dry-cured insulation systems for power transmission cables  

Energy Technology Data Exchange (ETDEWEB)

A detailed examination of the aging processes that may take place in solid-dielectric extruded-type high voltage transmission cables under dry conditions is presented. Particular emphasis is placed on the aging process as affected by the separate and simultaneous action of four main aging factors, namely the electrical, mechanical and thermal stresses, and the physical and chemical environment. A number of pertinent aging models are considered and their validity and applicability to accelerated aging tests on solid-type transmission cables are discussed.

1994-01-01

274

Accelerated-aging tests for predicting radiation degradation of organic materials  

Energy Technology Data Exchange (ETDEWEB)

Long-term aging of organic materials in reactor containment buildings has become a major issue within the nuclear community. In this article, the status of radiation-aging qualification test requirements in several countries is reviewed, and problems with the current aging methodologies are described. These problems include dose-rate and synergistic effects and environmental synergisms, which have been found for many different polymeric materials. A number of approaches to improved accelerated-radiation-aging tests for prediction of long-term aging behavior are discussed together with their limitations.

1984-03-01

275

Accelerated-aging tests for predicting radiation degradation of organic materials  

International Nuclear Information System (INIS)

Long-term aging of organic materials in reactor containment buildings has become a major issue within the nuclear community. In this article, the status of radiation-aging qualification test requirements in several countries is reviewed, and problems with the current aging methodologies are described. These problems include dose-rate and synergistic effects and environmental synergisms, which have been found for many different polymeric materials. A number of approaches to improved accelerated-radiation-aging tests for prediction of long-term aging behavior are discussed together with their limitations.

1984-01-01

276

War in the Information Age: A Primer for Cyberspace ...  

Science.gov (United States)

... A Primer for Cyberspace ... 4. TITLE AND SUBTITLE War in the Information Age: A Primer for Cyberspace Operations in 21st Century Warfare 5a. ...

2011-05-15

277

Tragedy and delight: the ethics of decelerated ageing  

UK PubMed Central (United Kingdom)

Biogerontology is sometimes viewed as similar to other forms of biomedical research in that it seeks to understand and treat a pathological process. Yet the prospect of treating ageing is extraordinary...Full Text Available

2011-01-12

278

The sites and topology of mitochondrial superoxide production  

UK PubMed Central (United Kingdom)

Mitochondrial superoxide production is an important source of reactive oxygen species in cells, and may cause or contribute to ageing and the diseases of ageing. Seven major sites of superoxide...Full Text Available

2010-08-01

279

Reversing B cell aging  

UK PubMed Central (United Kingdom)

Age-related alterations in the cellular composition of the B lineage are a major cause of the poor antibody response to vaccination and to infectious agents among the elderly population. The mechanisms...Full Text Available

280

Polyphenols and Aging  

UK PubMed Central (United Kingdom)

Age-associated changes within an individual are inherently complex and occur at multiple levels of organismal function. The overall decline in function of various tissues is known to play a...Full Text Available

2010-02-01

281

Oxidative Damage and the Prevention of Age-Related Cataracts  

UK PubMed Central (United Kingdom)

PurposeCataracts are often considered to be an unavoidable consequence of aging. Oxidative damage is a major cause or consequence of cortical and nuclear cataracts, the most common...Full Text Available

2010-09-01

282

Mitochondrial ROS production correlates with, but does not directly regulate lifespan in drosophila  

UK PubMed Central (United Kingdom)

The Mitochondrial Free Radical Theory of Aging (MFRTA) is currently one of the most widely accepted theories used to explain aging....Full Text Available

283

Mice as a Mammalian Model for Research on the Genetics of Aging  

UK PubMed Central (United Kingdom)

Mice are an ideal mammalian model for studying the genetics of aging: considerable resources are available, the generation time is short, and the environment can be easily controlled, an important...Full Text Available

2011-02-08

284

DUCTILITY RATIO OF AGED BETA TITANIUM ALLOY  

Science.gov (United States)

... Title : DUCTILITY RATIO OF AGED BETA TITANIUM ALLOY. Corporate Author : NEW YORK UNIV NY SCHOOL OF ENGINEERING AND SCIENCE. ...

1962-01-02

285

Considerations on Temperature, Longevity and Aging  

UK PubMed Central (United Kingdom)

A modest reduction in body temperature prolongs longevity and possibly retards aging in both poikilotherm and homeotherm animals. Some of the possible mechanisms mediating these effects are...Full Text Available

2008-06-01

286

Computational biology for ageing  

UK PubMed Central (United Kingdom)

High-throughput genomic and proteomic technologies have generated a wealth of publicly available data on ageing. Easy access to these data, and their computational analysis, is of great importance in...Full Text Available

2011-01-12

287

Can microRNAs act as biomarkers of aging?  

UK PubMed Central (United Kingdom)

Aging can be defined as a progressive decline in physiological efficiency regulated by an extremely complex multifactorial process. The genetic makeup of an individual appears to dictate this rate...Full Text Available

288

Apoptosis at Inflection Point in Liquid Culture of Budding Yeasts  

UK PubMed Central (United Kingdom)

Budding yeasts are highly suitable for aging studies, because the number of bud scars (stage) proportionally correlates with age. Its maximum stages are known ...Full Text Available

289

Age and the Thyrotropin Response to Hypothyroxinemia  

UK PubMed Central (United Kingdom)

Context: Some studies suggest altered pituitary functioning and TSH production with aging.Objective: Our objective was to test the hypothesis that less TSH production...Full Text Available

2010-08-01

290

Time Management in Acute Vertebrobasilar Occlusion  

International Nuclear Information System (INIS)

Acute vertebrobasilar occlusion (VBO) is associated with a high risk of stroke and death. Although local thrombolysis may achieve recanalization and improve outcome, mortality is still between 35% and 75%. However, without recanalization the chance of a good outcome is extremely poor, with mortality rates of 80-90%. Early treatment is a fundamental factor, but detailed studies of the exact time management of the diagnostic and interventional workflow are still lacking. Data on 18 patients were retrospectively evaluated. Time periods between symptom onset, admission to hospital, time of diagnosis, and beginning of intervention were correlated with postinterventional neurological status. The Glasgow Coma Scale and National Institute of Health Stroke Scale (NIHSS) were used to examine patients before and after local thrombolysis. Additionally, multivariate statistics were applied to reveal similarities between patients with neurological improvement. Primary ...

2009-03-01

291

Radioiodine dosimetry and prediction of consequences of thyroid exposure of the Russian population following the Chernobyl accident  

International Nuclear Information System (INIS)

In the early period after the Chernobyl accident, analysis of patterns of "1"3"1I exposure of the human thyroid showed that contaminated milk was the basic source of "1"3"1I intake among the inhabitants of Russia. The equipment and techniques used for measurement of the "1"3"1I content in the thyroids of these individuals are described in this work. A model of the "1"3"1I intake, taking into account protective actions, and a method of thyroid dose calculation are discussed. The mean thyroid dose and frequency distributions of the thyroid doses to inhabitants of towns and villages of the Bryansk, Tula and Orel regions of Russia are presented. The mean dose to the thyroids of children living in the villages was 2 to 5 times higher than the dose to adult thyroids; for children living in the towns, the mean dose was 1.5 to 12 times higher. The mean thyroid mass in adult inhabitants of the Bryansk region was 27 g, which exceeded the value for a standard man (20 g) and ...

292

RED NUGGETS AT z #approx# 1.5: COMPACT PASSIVE GALAXIES AND THE FORMATION OF THE KORMENDY RELATION  

International Nuclear Information System (INIS)

We present the results of Near-Infrared Camera and Multi-Object Spectrometer (NICMOS) imaging of a sample of 19 high-mass passively evolving galaxies with 1.2 < z < 2, taken primarily from the Gemini Deep Deep Survey (GDDS). Around 80% of galaxies in our GDDS sample have spectra dominated by stars with ages #approx#>1 Gyr. Our rest-frame R-band images show that most of these objects have compact regular morphologies which follow the classical R "1"/"4 law. These galaxies scatter along a tight sequence in the size versus surface brightness parameter space which defines the Kormendy relation. Around one-third (3/10) of the massive red objects in the GDDS sample are extraordinarily compact, with effective radii under 1 kpc. Our NICMOS observations allow the detection of such systems more robustly than is possible with optical (rest-frame UV) data, and while similar systems have been seen at z #approx#> 2, this is the first time such systems have been ...

2009-04-10

293

Probing the Early Stages of Low-Mass Star Formation in LDN 1689N: Dust and Water in IRAS 16293-2422A, B, and E  

CERN Document Server

We present deep images of dust continuum emission at 450, 800, and 850 micron of the dark cloud LDN 1689N which harbors the low-mass young stellar objects (YSOs) IRAS 16293-2422A and B (I16293A and I16293B) and the cold prestellar object I16293E. Toward the positions of I16293A and E we also obtained spectra of CO-isotopomers and deep submillimeter observations of chemically related molecules with high critical densities. To I16293A we report the detection of the HDO 1_01 - 0_00 and H2O 1_10 - 1_01 ground-state transitions as broad self-reversed emission profiles with narrow absorption, and a tentative detection of H2D+ 1_10 - 1_11. To I16293E we detect weak emission of subthermally excited HDO 1_01 - 0_00. Based on this set of submillimeter continuum and line data we model the envelopes around I16293A and E. The density and velocity structure of I16293A is fit by an inside-out collapse model, yielding a sound speed of a=0.7 km/s, an age of t=(0.6--2.5)e4 yr, and a ...

2004-01-01

294

Palynostratigraphy and palaeoenvironment of the Middle Jurassic Sortehat Formation (Neill Klinter Group), Jameson Land, East Greenland  

Energy Technology Data Exchange (ETDEWEB)

The grey-black mudstones of the Sonehat Formation form part of the Middle Jurassic fill of the Jameson Land Basin in East Greenland. The formation is exposed in the southernmost part of the north south-trending, Mesozoic rift system in East Greenland that was part of the epeiric seaway betaveen East Greenland and Norway. Sedimentological observations of the Sortehat Formation indicate deposition in an offshore marine setting that was typically low energy and periodically oxygen-deficient but was influenced by storm currents on occasion. Detailed palynological studies of the Sortehat Formation have resulted in the definition of theee palynological assemblage zones recognised at four localities, namely Enhjoerningen Dal and Pelion (north Jameson Land), the type section at Sortehat (central Jameson Land) and Albuen at Neill Klinter along Hurry Inlet (south-east Jameson Land). In stratigraphic order, these zones are termed the Botryococcus Assemblage Zone, the Naennoceratopsis gracilis- ...

2003-07-01

295

Late-onset Stargardt-like macular dystrophy maps to chromosome 1p13  

Energy Technology Data Exchange (ETDEWEB)

Stargardt`s disease (MIM 248200), originally described in 1909, is an autosomal recessive condition of childhood, characterized by a sudden and bilateral loss of central vision. Typically, it has an early onset (7 to 12 years), a rapidly progressive course and a poor final outcome. The central area of the retina (macula) displays pigmentary changes in a ring form with depigmentation and atrophy of the retinal pigmentary epithelium (RPE). Perimacular yellowish spots, termed fundus flavimaculatus, are observed in a high percentage of patients. We have recently reported the genetic mapping of Stargardt`s disease to chromosome 1p13. On the other hand, considering that fundus flavimaculatus (MIM 230100) is another form of fleck fundus disease, with a Stargardt-like retinal aspect but with a late-onset and a more progressive course, we decided to test the hypothesis of allelism between typical Stargardt`s disease and late-onset autosomal recessive fundus flavimaculatus. ...

1994-09-01

296

Large lignite steam generators with circulating fluidized bed combustion. Operating experience with a 290 t/h and 400 t/h plant in the RWE power station at Goldenberg; Grosse Braunkohle-Dampferzeuger mit zirkulierender Wirbelschichtfeuerung. Betriebserfahrungen aus der 290 t/h- und der 400 t/h-Anlage im Kraftwerk Goldenberg der RWE Energie AG  

Energy Technology Data Exchange (ETDEWEB)

Early in 1988 RWE decided to overhaul the power station at Goldenberg. This was necessary due to the age of the plant, the obligation to supply heat and process steam and recent amendments of environmental legislation. After analysing demands and needs one developed a plant concept with a 290 t/h and a 400 t/h steam generator. Due to lack of space the decision was made in favour of a circulating atmospheric fluidised bed combustion instead of steam generators with pulverised lignite combustion as these steam generators take up much more space due to the legally required desulphurisation plants for gaseous emissions. Apart from generating steam RWE wishes to gain experience with this combustion technology and test it for suitability and use in large-scale plant. (orig./KO) [Deutsch] Aufgrund des fortgeschrittenen Alters, der aktuellen Umweltschutzgesetzgebung sowie bestehender Versorgungsverpflichtungen fuer Waerme und Prozessdampf wurde Anfang ...

1995-12-31

297

Incredible Years Parent Training Support for Nursery Staff Working within a Disadvantaged Flying Start Area in Wales: A Feasibility Study  

Science.gov (United States)

Parenting programmes are effective interventions for preventing and treating conduct problems in young children. Up to 20% of children in disadvantaged areas have conduct disorder. Recent government initiatives such as targeting early years services to designated disadvantaged Flying Start areas in Wales have resulted in increased nursery-care provision for pre-schoolers, yet little has been done to equip nursery staff with effective child behaviour management strategies. The purpose of this non-randomised trial platform study was to establish the feasibility of delivery and the effectiveness of the new Incredible Years Toddler Parent Programme in supporting nursery staff in managing difficult behaviour in the nursery. The Parent Programme is a 12-session (a two-hour session/week) course for carers/parents of children aged one to three years old, which encourages carers to: establish positive relationships with children through play and ...

2010-12-01

298

Genetic control of immune response to pseudorabies and atrophic rhinitis vaccines: II. Comparison of additive direct and maternal genetic effects.  

Science.gov (United States)

Data from 52 litters farrowed in two seasons of a cross-fostering experiment were analyzed to estimate variances and covariances for additive direct and maternal genetic effects on immune response to pseudorabies virus and B. bronchiseptica vaccine. Twenty purebred boars and 44 sows of the Duroc, Landrace and Yorkshire breeds were used. Immune response was measured after vaccine challenge. A modified-live pseudorabies (PR) vaccine was administered to piglets at 28 d of age; response was measured by log2 serum neutralization titers at 56 d. An inactivated B. bronchiseptica bacterin was administered at 28, 42 and 112 d. Antibody levels were measured relative to positive and negative controls at 28, 56 and 119 d by using an enzyme-linked immunosorbent assay (ELISA). Results from this study for heritability were .18 +/- .09 for PR titer and .15 +/- .07 and .52 +/- .15 for 56- and 119-d ELISA values, respectively. The variability due to nurse environment (maternal ...

1987-02-01

299

Early and Late Bowel Complication Following Irradiation of Cancer of the Uterine Cervix-Whole Pelvis External Irradiation end High-Dose-Rate Interactively Irradiation  

International Nuclear Information System (INIS)

Cervix cancer is the most common female cancer in Korea. In spite of their relatively local invasive tendency, still 44% of patient will develop recurrent cancer This result suggests that more aggressive local treatment may increase the cure rate but increased complication risk also cannot be avoidable. Various institutions proposed different treatment regimen, but recommended dose were about 4500 cGy for whole pelvis and 8000 cGy at point A, even though they agreed that those doses may not be satisfactory for control of bulky disease. 96 cases of invasive cervical cancer, treated with postoperative or primary radiation therapy were analyzed to determine the complication rate and prognostic factor in our treatment regimen which is 500-1000 cGy higher than other institution. Mean follow up duration was 21 months. Symptomatic patients including mild but persistent abdominal discomfort was 46%, but only 1 patient (1%) had operative treatment because of incomplete obstruction of small ...

1989-06-01

300

Case report: Denys- Drash syndrome.  

Science.gov (United States)

BACKGROUND: Denys-Drash Syndrome (DDS) is an uncommon disorder that appears sporadically and in rare cases may be inherited as an autosomal dominant trait It manifests either at birth or within the first year of life and typically consists of the triad of congenital nephropathy, Wilms tumour and intersex disorder. CASE REPORT: A 10 year-old Caucasian girl was referred to the Dental Department, at Glasgow Royal Hospital for Sick Children by her Paediatric Nephrologist Consultant. The patient was being teased by her peers over her markedly discoloured teeth. The dental history revealed that the patient was a regular dental attendee from an early age. She was dentally anxious having only experienced dental treatment under general anaesthesia (GA) when she was 4 years old. Apparently her primary dentition also showed a generalised discolouration. TREATMENT: This consisted of multiple visits for diet analysis and tooth brushing instruction with the ...

2007-12-01

301

The role of imaging in the choice of correct treatment of unstable thoraco-lumbar fractures  

International Nuclear Information System (INIS)

The concept of unstable burst fracture has been discussed since over 50 years and this injury has received much attention in the literature as regards its radiological diagnosis and clinical treatment. The purpose of this article is to review the way we use imaging to diagnose the injury and to guide treatment.

2006-09-01

302

The Primary Patency and Fracture Rates of Self-Expandable Nitinol Stents Placed in the Popliteal Arteries, Especially in the P2 and P3 Segments, in Korean Patients  

Energy Technology Data Exchange (ETDEWEB)

We wanted to evaluate the status of self-expandable nitinol stents implanted in the P2 and P3 segments of the popliteal artery in Korean patients. We retrospectively analyzed 189 consecutive patients who underwent endovascular treatment for steno occlusive lesions in the femoropopliteal artery from July 2003 to March 2009, and 18 patients who underwent stent placement in popliteal arterial P2 and P3 segments were finally enrolled. Lesion patency was evaluated by ultrasound or CT angiography, and stent fracture was assessed by plain X-rays at 1, 3, 6 and 12 months and annually thereafter. At the 1-month follow-up, stent fracture (Type 2) was seen in one limb (up to P3, 1 of 18, 6%) and it was identified in seven limbs at the 3-month follow-up (Type 2, Type 3, Type 4) (n = 1: up to P2: n = 6: P3). At the 6-month follow-up, one more fracture (Type 1) (up to P3) was noted. At the 1-year follow-up, there were no additional stent ...

2011-04-15

303

Neglected simultaneous bilateral femoral neck fractures secondary to narcotic drug abuse treated by bilateral one-staged hemiarthroplasty: a case report  

UK PubMed Central (United Kingdom)

Simultaneous bilateral femoral neck fractures are extremely rare and associated with various conditions. Up to now Most cases had correlations with major trauma, repetitive minor trauma, seizure, parathyroid...Full Text Available

304

Discriminative ability of total body bone-mineral measured by dual photon absorptiometry  

Energy Technology Data Exchange (ETDEWEB)

We investigated the descriminative ability of total body bone-mineral expressed as the total body bone-density (TBBD) measured by dual photon absorptiometry (DPA) in 79 healthy premenopausal women, 27 healthy postmenopausal women, and 120 female osteoporotic fracture patients presenting with either Colles' fracture, vertebral fracture or femoral neck-fracture. TBBD was compared to the bone-mineral density of the lumbar spine (BMD{sub spine}) also measured by DPA, and to the bone-mineral content of the forearms (BMC{sub forearm}) measured by single photon absorptiometry (SPA). TBBD, BMD{sub spine} and BMC{sub forearm} showed that all the fracture patient groups had significantly reduced bone-mass. Using receiver operating characteristic (ROC) analysis, we found that TBBD had a tendency towards better discriminative ability than BMD{sub spine} or BMC{sub forearm} with regard ...

1989-04-01

305

Diagnostic imaging of the acutely injured patient  

Energy Technology Data Exchange (ETDEWEB)

This book provides an analysis of pathophysiologic concepts of trauma and reviews the effectiveness of the available imaging modalities in acute trauma of various organ system. Topics covered are chest injuries; abdominal trauma; fractures of long bones; the foot and ankle; the knee; hand and wrist; the elbow; the shoulder; the pelvis hips; the spine; the skull and facial trauma and the clinical assessment of multiple injuries patients. Comparative evaluation of diagnostic techniques of radiography is discussed. Normal anatomy and bone fractures along with soft-tissue injuries are described.

1985-01-01

306

A pragmatic study exploring the prevention of delirium among hospitalized older hip fracture patients: Applying evidence to routine clinical practice using clinical decision support  

UK PubMed Central (United Kingdom)

Delirium occurs in up to 65% of older hip fracture patients. Developing delirium in hospital has been associated with a variety of adverse outcomes. Trials have shown that multi-component preventive...Full Text Available

307

Unsaturated zone flow modeling for GWTT-95  

Energy Technology Data Exchange (ETDEWEB)

In accordance with the Nuclear Regulatory Commission regulation regarding groundwater travel times at geologic repositories, various models of unsaturated flow in fractured tuff have been developed and implemented to assess groundwater travel times at the potential repository at Yucca Mountain, Nevada. Kaplan used one-dimensional models to describe the uncertainty and sensitivity of travel times to various processes at Yucca Mountain. Robey and Arnold et al. used a two-dimensional equivalent continuum model (ECM) with inter- and intra-unit heterogeneity in an attempt to assess fast-flow paths through the unsaturated, fractured tuff at Yucca Mountain (GWTT-94). However, significant flow through the fractures in previous models was not simulated due to the characteristics of the ECM, which requires the matrix to be nearly saturated before flow through the fractures is initiated. In the current study ...

1995-12-31

308

Prognostic precision in postoperative /sup 99m/Tc-MDP scintimetry after femoral neck fracture  

Energy Technology Data Exchange (ETDEWEB)

A 2-year follow-up regarding healing complications, such as redisplacement, nonunion, and segmental collapse of the femoral head, was performed in 306 patients operated on for femoral neck fracture and examined with /sup 99m/Technetium-MDP scintimetry within 2 weeks postoperatively. Scintimetric evaluation was performed by selecting regions of interest over the femoral head on the fracture side and the intact side and by comparing the uptake. A femoral head ratio fractured/intact side thus was obtained. Of 199 patients with an intact femoral head uptake (ratio less than or equal to 1.0), 181 showed no signs of healing complications at 2 years, whereas 18 had developed healing complications. Of 107 cases with a deficient femoral-head uptake (ratio < 1.0), 96 had developed healing complications within 2 years from the operation, while 11 cases had no signs of radiographic complications. We conclude that /sup 99m/Tc-MDP ...

1987-01-01

309

Prognostic precision in postoperative "9"9"mTc-MDP scintimetry after femoral neck fracture  

International Nuclear Information System (INIS)

A 2-year follow-up regarding healing complications, such as redisplacement, nonunion, and segmental collapse of the femoral head, was performed in 306 patients operated on for femoral neck fracture and examined with "9"9"mTechnetium-MDP scintimetry within 2 weeks postoperatively. Scintimetric evaluation was performed by selecting regions of interest over the femoral head on the fracture side and the intact side and by comparing the uptake. A femoral head ratio fractured/intact side thus was obtained. Of 199 patients with an intact femoral head uptake (ratio #<=# 1.0), 181 showed no signs of healing complications at 2 years, whereas 18 had developed healing complications. Of 107 cases with a deficient femoral-head uptake (ratio < 1.0), 96 had developed healing complications within 2 years from the operation, while 11 cases had no signs of radiographic complications. We conclude that "9"9"mTc-MDP scintimetry performed ...

310

Low field magnetic resonance imaging of femoral neck fractures  

International Nuclear Information System (INIS)

Fourteen patients with cervical hip fractures were treated with internal fixation using titanium screws. The femoral head vitality was evaluated with "9"9Tc"m-MDP scintigraphy and scintimetry within 2 weeks postoperatively and by serial low field magnetic resonance imaging (MR). Two patients with reduced radionuclide uptake (femoral head ratio =# 1.0), MR revealed a focal decrease of the signal intensity in the femoral head or neck at 2, 3 and 7 months after fracture, respectively. The radiographs in one of these patients were normal at 7 months after fracture. The second one showed signs of necrosis at 16 months and the last one developed delayed/non-union. With a non-ferromagnetic osteosynthesis the healing course after femoral neck fracture can be studied with low field MR equipment without disturbing artifacts. The time period between ischaemia and definite abnormalities on MR may embrace several ...

311

Influence of second phase particles on fracture toughness in AZ31 magnesium alloys  

Energy Technology Data Exchange (ETDEWEB)

Three kinds of thin AZ31 wrought magnesium alloys sheets were used in order to investigate the influence of the second phase particles on fracture toughness. From the theoretical model, the ratio of {lambda}{sub p}/d{sub p} would be estimated 5 {proportional_to} 6. On the other hand, from the microstructural observation, average particle spacing on each material was sample A: 13.1 {mu}m, sample B: 14.1, and sample C: 12 {mu}. In addition, average particle size on each sample was sample A: 2.1, sample B: 1.9, and sample C: 2.3 {mu}m. Therefore, the ratio of {lambda}{sub p}/d{sub p} calculated from fracture surface observation would be predicted 6 {proportional_to} 7. In comparison with the result of the prediction by theoretical analysis was in good agreement with the result of fracture toughness observation. It was found that the variation in plane-strain fracture toughness on AZ31 were affected by both ...

2004-07-01

312

High resolution Computed Tomography in the study of temporal bone trauma  

International Nuclear Information System (INIS)

Thirty-five patients with temporal bone fractures were examined; the fractures were sometimes associated with dislocation of the assicular chain caused by road fatalities. Computed Tomography (CT) was performed either because of the presence of clinical symptoms associated with trauma of the temporal bone, because of a hemotympanum discovered during a CT scan of the brain. Thirty-three fractures were detected: 19 longitudinal, 6 transverse, and 8 complex. An incudostapedial dislocation was also detected, together with a displacement of a stapedial prosthesis from the lenticular process of incus, and 3 incus-malleus dislocation associated with fractures. High resolution CT allows the precise definition of the course of the fractures, of the associated dislocation of the ossicular chain, and of facial nerve lesion, thus allowing a more accurate surgical intervention. In the ...

1988-01-01

317

Postweld aging of a metastable beta-titanium alloy  

International Nuclear Information System (INIS)

(Nov 1973). United States Greenfield, MA Pierce, CM Chicago, IL.

318

Monovision  

Medline Plus

... Precautions Comprehensive Eye and Vision Examination Nutrition Lutein Antioxidants & Age-Related Eye Disease Lutein and Zeaxanthin - Eye- ...

322

Foreign Affair's: Fool's Gold  

Wastenet

aged gracefully: premature and accelerated corro - sion, erosion, and stress are raising maintenance costs.Last

323

Rb-Sr ages and palaeomagnetic data for some Angolan alkaline intrusives  

International Nuclear Information System (INIS)

New Rb-Sr age measurements are reported for a number of intrusives from Angola. Data for the Njoio and Tchivira nepheline syenite bodies yield mineral isochrons indicating ages of 104,3+-0,8 Ma and 130,8+-1,4 Ma respectively. Palaeomagnetic studies on the same occurrences gave marginal and scattered results respectively. Micas from the Camafuca crater-facies kimberlite yielded and apparent age of 1 822+-151 Ma, a result that is far in excess of the Tertiary (or younger) age inferred for this pipe. Similarly conflicting data were obtained for the Nova Lisboa kimberlite. It is likely that older crustal micas incorporated in the kimberlite breccias are responsible for the anomalous ages reported on the kimberlites. Satisfactory palaeomagnetic data are reported for the Zenza and Bailundu occurrences, not dated by the Rb-Sr method. A convenient K-Ar age of 80+-0,8 Ma ...

324

Precipitation behavior and tensile property of the stress-aged Ti-10Mo-8V-1Fe-3.5Al alloy  

British Library Electronic Table of Contents (United Kingdom)

A kind of metastable beta titanium alloy, i.e. Ti-10Mo-8V-1Fe-3.5Al, was aged under elastic compressive stress. Transmission electron microscopy (TEM) investigations revealed that, in the stress-aged samples, precipitated alpha plates were parallel to each other. However, in the conventionally aged samples, alpha plates intersected each other. In other words, variant of alpha plate was selected in the stress-aged samples. Tensile tests showed that, at equivalent tensile strength, the stress-aged samples exhibited higher ductility, compared to the conventionally aged ones.

2011-01-01

325

Safe ageing management of nuclear power plants: An European synthesis  

International Nuclear Information System (INIS)

Ageing of nuclear power plants means evolution of material or equipment properties on one side, and evolution of personnel skill and procedure adequacy on the other side, both of which, after a certain time, may not be compatible with the required safety provisions, or with an economic operation of the plant. Repair or replacement of components, as well as change in service conditions for a better compatibility with component reduced capabilities can be used to mitigate ageing effects. The paper summarises the results of a study conducted in this field with the support of the European Commission. It presents: the synthesis of the work done under international auspices, and in the European context; the comparison of ageing management approaches used in several European countries with international recommendations; the summary of the various potential phenomena and their governing parameters, the methods of in-service ...

2002-11-04

326

The adenovirus-2 EIIa early gene promoter: sequences required for efficient in vitro and in vivo transcription.  

UK PubMed Central (United Kingdom)

A series of deletion mutants extending from -250 toward the capsite has been constructed in the early promoter region of the adenovirus 2 EIIa gene and tested both in vitro, and in vivo after transfection...Full Text Available

1983-10-25

327

Sunbed use during adolescence and early adulthood is associated with increased risk of early-onset melanoma  

UK PubMed Central (United Kingdom)

Sunbed use is associated with increased risk of melanoma. Younger people might be more susceptible to the carcinogenic effects of ultraviolet radiation. We investigated the association between...Full Text Available

2011-05-01

328

Stage-specific protein synthesis during early embryogenesis in Drosophila melanogaster.  

UK PubMed Central (United Kingdom)

The changes in protein species synthesized during early Drosophila embryogenesis were characterized by two-dimensional electrophoresis. Of the 261 proteins scored, 68 (26%) show dramatic changes in...Full Text Available

1983-01-01

329

Sequential Molecular and Cellular Events during Neoplastic Progression: A Mouse Syngeneic Ovarian Cancer Model1  

UK PubMed Central (United Kingdom)

AbstractStudies performed to identify early events of ovarian cancer and to establish molecular markers to support early detection and development of chemopreventive regimens have been...Full Text Available

2005-10-01

330

One-Year Durability of the Effects of Cognitive Enhancement Therapy on Functional Outcome in Early Schizophrenia  

UK PubMed Central (United Kingdom)

Cognitive rehabilitation is an effective intervention for addressing cognitive impairments in patients with schizophrenia. Previous research has shown that the early application of Cognitive...Full Text Available

2010-07-01

331

Muscularis mucosae in desmoplastic stroma formation of early invasive rectal adenocarcinoma  

UK PubMed Central (United Kingdom)

The origin of myofibroblasts or myofibroblastic cells in the desmoplastic stroma associated with carcinoma invasion has been controversial. In the early invasive area of a rectal adenocarcinoma reported...Full Text Available

2009-10-21

332

Multiparameter Phospho-Flow Analysis of Lymphocytes in Early Rheumatoid Arthritis: Implications for Diagnosis and Monitoring Drug Therapy  

UK PubMed Central (United Kingdom)

BackgroundThe precise mechanisms involved in the initiation and progression of rheumatoid arthritis (RA) are not known. Early stages of RA often have non-specific symptoms, delaying...Full Text Available

333

Monitoring of Tumor Promotion and Progression in a Mouse Model of Inflammation-Induced Colon Cancer with Magnetic Resonance Colonography1  

UK PubMed Central (United Kingdom)

Early detection of precancerous tissue has significantly improved survival of most cancers including colorectal cancer (CRC). Animal models designed to study the early stages of cancer are valuable...Full Text Available

2009-03-01

334

Metal stenting to resolve post-photodynamic therapy stricture in early esophageal cancer  

UK PubMed Central (United Kingdom)

Photodynamic therapy (PDT) is an established endoscopic technique for ablating Barrett’s esophagus with high-grade dysplasia or early-stage intraepithelial neoplasia. The most common clinically...Full Text Available

2011-03-14

335

Inheritable Effect of Unpredictable Maternal Separation on Behavioral Responses in Mice  

UK PubMed Central (United Kingdom)

The long-term impact of early stress on behavior and emotions is well documented in humans, and can be modeled in experimental animals. In mice, maternal separation during early postnatal development...Full Text Available

336

Infant Milk Feeding Influences Adult Bone Health: A Prospective Study from Birth to 32 Years  

UK PubMed Central (United Kingdom)

BackgroundPeak bone mass, attained by early adulthood, is influenced by genetic and life-style factors. Early infant feeding and duration of breastfeeding in particular, associate...Full Text Available

337

Human Immunodeficiency Virus-1 Inhibition of Immunoamphisomes in Dendritic Cells Impairs Early Innate and Adaptive Immune Responses  

UK PubMed Central (United Kingdom)

SUMMARYDendritic cells (DCs) in mucosal surfaces are early targets for human immunodeficiency virus-1 (HIV-1). DCs mount rapid and robust immune responses upon pathogen encounter....Full Text Available

2010-05-28

338

Early auditory experience generates long-lasting memories that may subserve vocal learning in songbirds  

UK PubMed Central (United Kingdom)

In both humans and songbirds, infants learn vocalizations by imitating the sounds of adult tutors with whom they interact during an early sensitive period. Vocal learning occurs in few animal taxa;...Full Text Available

2006-01-24

339

Early Wound Healing Following One-Stage Dental Implant Placement With and Without Antibiotic Prophylaxis: A Pilot Study  

UK PubMed Central (United Kingdom)

BackgroundOne-stage implant placement has clinically acceptable treatment outcomes. Among other advantages, it may allow investigation of early wound healing. The...Full Text Available

2008-10-01

340

EARLY FLOWERING3 Encodes a Novel Protein That Regulates Circadian Clock Function and Flowering in Arabidopsis  

UK PubMed Central (United Kingdom)

Higher plants use photoperiodic cues to regulate many aspects of development, including the transition from vegetative to floral development. The EARLY FLOWERING3 (ELF3)...Full Text Available

2001-06-01

341

Cross sectional early mitral flow velocity profiles from colour Doppler.  

UK PubMed Central (United Kingdom)

Instantaneous cross sectional flow velocity profiles from early mitral flow in 10 healthy men were constructed by time interpolation of the velocity data from each point in sequentially delayed two...Full Text Available

1989-09-01

342

Characterization of the 5'-terminal cap structures of early simian virus 40 mRNA.  

UK PubMed Central (United Kingdom)

Early simian virus 40-specific mRNA was isolated from lytically infected and stably transformed cells and analyzed with respect to the 5'-terminal cap content. An analogous diversity of capped structures...Full Text Available

1980-09-01

343

SPACE FLIGHT 1999 - NASA  

Science.gov (United States)

Mission losses were incurred by an early warning satellite and a Milstar-2 communications satellite when their launch vehicles malfunctioned, the first, ...

345

Early axial spondyloarthritis  

UK PubMed Central (United Kingdom)

Purpose of reviewTo summarize recent advances in the classification of preradiographic axial spondyloarthritis (SpA).Recent findingsFull Text Available

2010-09-01

346

Early Season Applications of Fluridone for Control of Curlyleaf ...  

Science.gov (United States)

... While the large tanks served to regulate the water temper- ature, the polypropylene aquaria served as independent experimental units. ...

2010-12-01

347

Early Life Crises of Habitable Planets  

ScienceCinema

...global warming such such a pressing ...global warming and actually for all climate change problems that ...for the global warming problem ...

348

Demonstration of Synchronization Between Two ...  

Science.gov (United States)

... Abstract in early 1996 Milstar became the first geosynchronous satellife system to employ crosslinks for synchronization and syntoniulfion. ...

1996-12-01

350

A Study of the Geographic Origin, Education, and Experience ...  

Science.gov (United States)

... by starting and remaining in that size hotel. Another early study, conducted by Nailon (1968) sampled three general managers ...

1993-04-01

351

Staging of multiple myeloma with MRI: comparison to MSCT and conventional radiography; Staging des multiplen Myeloms mit der MRT: Vergleich zur MSCT und zur konventionellen Roentgendiagnostik  

Energy Technology Data Exchange (ETDEWEB)

The staging of patients with multiple myeloma demands sensitive imaging methods for the assessment of the skeletal system. MRI allows for direct visualization of the bone marrow which exhibits five different infiltration patterns in multiple myeloma: 1. normal appearance of the bone marrow, 2. focal involvement, 3. homogeneous diffuse infiltration, 4. combined diffuse and focal infiltration, 5. ''salt and pepper'' pattern with inhomogeneous bone marrow signals due to multiple fat islands. The combination of T1w-SE and STIR sequences is best suited for detecting all infiltration patterns and for the differential diagnoses e. g. hemangiomas. With parallel imaging in MRI, acquisition times can be markedly reduced and whole-body screening of the bone marrow can be achieved within 30 min. MRI is superior to radiography for the detection of focal as well as diffuse infiltration. Multidetector computed tomography and especially 16- and 64-detector row ...

2004-09-01

352

Measurement results of BHTV logging at the geothermal well. 1; Chinetsusei ni okeru BHTV kenso no sokutei kekka. 1  

Energy Technology Data Exchange (ETDEWEB)

In association with excavation of the No. 135 steam producing well in the Onikubi geothermal power plant in Miyagi Prefecture, shapes of production zones and drilling-induced fracture (DIF) were acquired from the borehole televiewer (BHTV) data. The BHTV logging shoots sound waves onto well walls of wells filled with fluid and detects the reflection waves to investigate the state of the well walls. Vertical fracture with opening lengths from 2 to 3 m were found at depths of about 1232 m and 1312 m. Water run-off has occurred at a depth of about 1312 m during the excavation, to which these vertical fractures might have contributed possibly. In depths of about 1232 m and 1312 m, fractures inclining toward north-east direction and south-west direction are predominant. Some fractures in the depth of about 1333 m incline toward east-south-east direction and west-north-west direction. ...

1997-05-27

353

Development of experimental verification techniques for non-linear deformation and fracture on the nanometer scale.  

Energy Technology Data Exchange (ETDEWEB)

This work covers three distinct aspects of deformation and fracture during indentations. In particular, we develop an approach to verification of nanoindentation induced film fracture in hard film/soft substrate systems; we examine the ability to perform these experiments in harsh environments; we investigate the methods by which the resulting deformation from indentation can be quantified and correlated to computational simulations, and we examine the onset of plasticity during indentation testing. First, nanoindentation was utilized to induce fracture of brittle thin oxide films on compliant substrates. During the indentation, a load is applied and the penetration depth is continuously measured. A sudden discontinuity, indicative of film fracture, was observed upon the loading portion of the load-depth curve. The mechanical properties of thermally grown oxide films on various substrates were ...

2005-11-01

354

Development of Intelligent Setting System for Fracture Based on X-Ray Image  

Energy Technology Data Exchange (ETDEWEB)

In order to achieve micro-wound, intelligence and high efficiency for fracture setting, intelligent setting system for fracture is proposed in accordance with biomechanics and fracture therapy theory. In the comprehensive medical system based on C-shape-arm X-machine, image processing and analysis is the core, programmable logical controller and stepping motor are important driving parts controlling mechanical parts. Six degree of freedom dynamics sensor ensures to control accurately force and moment. On the foundation of analyzing X-ray image peculiarities, method of processing and analysis is put forward, combining time domain with frequency domain. After mining domain knowledge in depth, setting actions is quantized into three non-continuous steps and is parameterized into two angles and one distance aiming at femoral-neck fracture. Objective features are extracted by virtue of three power ...

2006-10-15

355

Simultaneous plasma nitriding and ageing treatments of precipitation hardenable plastic mould steel  

Energy Technology Data Exchange (ETDEWEB)

Simultaneous nitriding and ageing heat treatments of precipitation hardenable tool steel was carried out inside a DC-pulsed plasma nitriding reactor. A single heat treatment cycle was done, as the plasma nitriding and age hardening processes occur approximately at the same ranges of temperatures and times. Specimens of Cr-Ni-Mo-Al age hardenable steel, in the solubilized and solubilized and aged conditions, were tested. Plasma nitriding and ageing, carried out at 500 deg. C for times ranging between 2 and 8 h, increased the surface hardness up to 1000 HV, producing case depths between 100 and 200 {mu}m. The core hardness of solubilized samples increased from 30 to 39 Rockwell C after the plasma nitriding treatment proving the possibility of nitriding and ageing at the same treatment cycle. The pre-aged samples did not show any overageing ...

2007-07-01

356

Simultaneous plasma nitriding and ageing treatments of precipitation hardenable plastic mould steel  

International Nuclear Information System (INIS)

Simultaneous nitriding and ageing heat treatments of precipitation hardenable tool steel was carried out inside a DC-pulsed plasma nitriding reactor. A single heat treatment cycle was done, as the plasma nitriding and age hardening processes occur approximately at the same ranges of temperatures and times. Specimens of Cr-Ni-Mo-Al age hardenable steel, in the solubilized and solubilized and aged conditions, were tested. Plasma nitriding and ageing, carried out at 500 deg. C for times ranging between 2 and 8 h, increased the surface hardness up to 1000 HV, producing case depths between 100 and 200 #mu#m. The core hardness of solubilized samples increased from 30 to 39 Rockwell C after the plasma nitriding treatment proving the possibility of nitriding and ageing at the same treatment cycle. The pre-aged samples did not show any overageing ...

357

Ageing assessments with application of PSA Models  

International Nuclear Information System (INIS)

One of the main applications of PSA studies is related to identification of the major key issues related to plant safety. In standard PSA one assumes a constant value for component failure rates by considering that the component doesn't experience any degradation that could affect its performance. Used in this manner, standard PSA tools do not adequately address important ageing issues, and this fact could have a significant impact on the conclusions drawn from PSA studies and applications, in conditions of operation of ageing plants. To obtain realistic results, it is necessary to consider in the PSA model the ageing effects, and to do that it is necessary to take into consideration the change in component failure rate as a function of component age. In case of ageing phenomena, this dependence causes the failure rate of a component (or a set of components) to increase in time as ...

2009-10-12

358

The use of tracers to analyze the effects of reinjection into fractured geothermal reservoirs  

Science.gov (United States)

This paper discusses the use of tracers as a reservoir engineering tool in fractured geothermal reservoirs. The principle concern in injecting cooler spent fluids into a fractured reservoir is that the fluids may move through high permeability channels and return to the production wells after contacting a relatively small volume of rock. As a consequence of this rapid transport, the fluids will be only partially reheated and after a short period time will effectively mine the heat from the limited volume of rock. The production wells will then experience a rapid and premature reduction in thermal output. Tracers can be used to infer the existence of high mobility conduits between injection and production wells and to monitor chemical changes of an injected fluid. Since tracer arrival precedes thermal breakthrough, tracer tests are a very useful forecasting tool.

1987-01-01

359

Superselective intra-arterial DSA in patients with femoral head necrosis and femoral neck fracture. Superselektive intraarterielle DSA bei Hueftkopfnekrose und Schenkelhalsfraktur  

Energy Technology Data Exchange (ETDEWEB)

The prospective study includes 25 patients without pathology of the femoral head for the evaluation of the normal femoral head perfusion. In addition 34 patients with femoral head necrosis underwent i.a. DSA preoperatively before pedicled pelvic bone grafting. 15 patients after pelvic bone graft operation and 7 patients with medial femoral head fracture were also examined via superselective DSA. In cases with femoral head necrosis a rarefaction or interruption of the rami nutricii proximales, or an occlusion of the medial circumflex femoral artery were observed. Patients with medial femoral neck fracture showed an interruption of the rami nutricii proximales of the femoral head. Postoperative DSA - after pedicled pelvic bone graft - revealed a regular arterial graft perfusion in 82%. (orig.).

1991-06-01

360

Structure, mechanical properties, and dynamic fracture in nanophase silicon nitride via parallel molecular dynamics  

Energy Technology Data Exchange (ETDEWEB)

Million-atom molecular-dynamics (MD) simulations are performed to study the structure, mechanical properties, and dynamic fracture in nanophase Si{sub 3}N{sub 4}. The authors find that intercluster regions are highly disordered: 50% of Si atoms in intercluster regions are three-fold coordinated. Elastic moduli of nanophase Si{sub 3}N{sub 4} as a function of grain size and porosity are well described by a multiphase model for heterogeneous materials. The study of fracture in the nanophase Si{sub 3}N{sub 4} reveals that the system can sustain an order-of-magnitude larger external load than crystalline Si{sub 3}N{sub 4}. This is due to branching and pinning of the crack front by nanoscale microstructures.

1997-09-01

361

Numerical evaluation of effective unsaturated hydraulic properties for fractured rocks  

Energy Technology Data Exchange (ETDEWEB)

To represent a heterogeneous unsaturated fractured rock by its homogeneous equivalent, Monte Carlo simulations are used to obtain upscaled (effective) flow properties. In this study, we present a numerical procedure for upscaling the van Genuchten parameters of unsaturated fractured rocks by conducting Monte Carlo simulations of the unsaturated flow in a domain under gravity-dominated regime. The simulation domain can be chosen as the scale of block size in the field-scale modeling. The effective conductivity is computed from the steady-state flux at the lower boundary and plotted as a function of the averaging pressure head or saturation over the domain. The scatter plot is then fitted using van Genuchten model and three parameters, i.e., the saturated conductivity K{sub s}, the air-entry parameter {alpha}, the pore-size distribution parameter n, corresponding to this model are considered as the effective K{sub s}, effective {alpha}, and ...

2009-01-01

362

Influence of pH, temperature and thermal treatment on site corrosion of SAE 304 steel in chlorinated solutions  

International Nuclear Information System (INIS)

The electrochemical behaviour and fracture morphology of homogenized and sensitized type SAE 304 stainless steel U bent specimens, in 3% NaCl solution, at pH=2.0 and pH=7.0 both at room temperature and 100"0C was studied. Polarization curves, galvanostatic and potentiostatic experiments were run. It could be observed that high temperature and low pH favour transgranular cracking and longer sensitization times lower fracture time and tend to give rise to intergranular fracture. Light sensitization can produce transgranular cracking even at room temperature, when the homogenized alloy does not present stress-corrosion cracking for the same condition. (Author).

363

Elastic properties, hardness and indentation fracture toughness of #beta#-sialons  

International Nuclear Information System (INIS)

Dense samples of #beta#-sialons (with z from 1 to 4) were pressuressly sintered for different time (15-240 minutes) and at relatively low temperature of 1600 C using single-phase #beta#-sialon powders synthesized by combustion nitridation. The samples were characterized using ultrasonic method for determination of elastic properties (E,G,#mu#). Also, hardness by Knoop and fracture toughness by Vickers indentation microfracture method was estimated. With increasing z number Young's modulus decreases from 293 to 179 GPa. Simultaneously Poisson ratio increases by about 30%. The highest values of hardness and fracture toughness were obtained for sialon with z equal to 1. (orig.).

1993-10-04

364

Absence of positive effect of black cohosh (Cimicifuga racemosa) on fracture healing in osteopenic rodent model  

British Library Electronic Table of Contents (United Kingdom)

Abstract The healing of predominantly metaphyseal fractures in postmenopausal osteoporosis is delayed and comparatively poor. Due to the potential side effects of HRT, natural alternatives are appealing. The aim of this study was to determine whether Cimicifuga racemosa extract BNO 1055 improves metaphyseal fracture healing in severe osteopenic bone in rats. Thirty three 12 week old female rats developed severe osteopenia during 10 weeks after ovariectomy. After metaphyseal tibial osteotomy and standardized T plate osteosynthesis, the healing periods in ovariectomized rats (C), 17 estradiol (E) and Cimicifuga racemosa (CR) supplemented diets were assessed for 35 days. Changes in callus morphology were evaluated qualitatively by biomechanical testing and quantitatively in microradiographies...

2010-01-01

365

Early Language Learning and Literacy: Neuroscience Implications for Education  

British Library Electronic Table of Contents (United Kingdom)

The last decade has produced an explosion in neuroscience research examining young children's early processing of language that has implications for education. Noninvasive, safe functional brain measurements have now been proven feasible for use with children starting at birth. In the arena of language, the neural signatures of learning can be documented at a remarkably early point in development, and these early measures predict performance in children's language and pre-reading abilities in the second, third, and fifth year of life, a finding with theoretical and educational import. There is evidence that children's early mastery of language requires learning in a social context, and this finding also has important implications for education. Evidence relating socioeconomic status (SES) ...

2011-01-01

366

The influence of aging on the intergranular corrosion of 22 chromium-5 nickel duplex stainless steel  

International Nuclear Information System (INIS)

Duplex stainless steels are widely used in severe corrosion environments because of their good corrosion performance. This paper deals with the influence of aging treatments on the intergranular corrosion (IGC) resistance of a commercial duplex stainless steel, SAF 2205. Duplex stainless steel was given aging treatments in the range 773-1173 K for time periods ranging from 6 min to 100 h. Optical microscopy and XRD was carried out on the aged stainless steels for the microstructural study. The aged samples were evaluated for the IGC susceptibility with the ASTM standard practices. Potentiodynamic cyclic polarization studies were also carried out to investigate the influence of aging treatments on the passivity breakdown. The results indicate that the sigma phase gets precipitated and is responsible for grain boundary attack. (author).

367

Predatory senescence in ageing wolves  

British Library Electronic Table of Contents (United Kingdom)

Abstract It is well established that ageing handicaps the ability of prey to escape predators, yet surprisingly little is known about how ageing affects the ability of predators to catch prey. Research into long-lived predators has assumed that adults have uniform impacts on prey regardless of age. Here we use longitudinal data from repeated observations of individually-known wolves (Canis lupus) hunting elk (Cervus elaphus) in Yellowstone National Park to demonstrate that adult predatory performance declines with age and that an increasing ratio of senescent individuals in the wolf population depresses the rate of prey offtake. Because this ratio fluctuates independently of population size, predatory senescence may cause wolf populations of equal size but different age structure to have d...

2009-01-01

368

Nuclear new-build - Status and Outlook from a German utility perspective  

International Nuclear Information System (INIS)

Full text: As one of the Top 5 utilities in Europe, Rheinisch-Westfaelisches Elektrizitaetswerk AG, FWB: RW, RWE, operates a diversified generating capacity of about 45 GW; RWE Power alone generates over 30 GW. Besides a share of approximately 20% nuclear power, a large proportion of the generating base is in lignite and hard coal. RWE has an ambitious, Euro10 bn newbuild program of about 10 GW modern fossil fired plants and further expansion plans across Europe. By 2012, RWE intends to invest between Euro 15 and 20 bn outside Germany.The European Union has a challenging policy to increase the share of renewables, improve energy efficiency, and reduce greenhouse gases by 2020. At the same time, ageing power plants need to be replaced. This requires an enormous investment program across Europe. Nuclear power therefore, as a proven technology with low lifecycle carbon emissions and reasonable lifecycle cost, is a crucial contributor to achieve Europe's 2020 goals. ...

2009-10-12

369

Liver trauma from penetrating injuries. Miscellanea, personal series, clinical and CT findings  

International Nuclear Information System (INIS)

Penetrating liver wounds are related to many causes and rank second after blunt abdominal and liver trauma. In this report are examined the clinical and radiological findings of personal series of patients with penetrating trauma, especially by firearms and stab and cut wounds. It will also tried to define the diagnostic workup of these traumas, which is especially based on CT signs of liver damage and associated changes and which is of basic importance for following treatment, both surgical or conservative. In the last seven years it was retrospectively reviewed 31 cases of penetrating liver trauma. The patients were 19 men and 12 women, ranging in age 18 to 73 (mean 42), with penetrating liver injuries from firearms (16 patients) and stab (9 cases) wounds; 6 patients had injuries from different cases. Abdominal CT was carried out in emergency with the CT Angiography (CTA) technique in all patients. In the patients with suspected chest and abdomen involvement CT ...

2000-12-01

370

In vitro MRI of brain development  

International Nuclear Information System (INIS)

In this review, we demonstrate the developmental appearance, structural features, and reorganization of transient cerebral zones and structures in the human fetal brain using a correlative histological and MRI analysis. The analysis of postmortem aldehyde-fixed specimens (age range: 10 postovulatory weeks to term) revealed that, at 10 postovulatory weeks, the cerebral wall already has a trilaminar appearance and consists of: (1) a ventricular zone of high cell-packing density; (2) an intermediate zone; (3) the cortical plate (in a stage of primary consolidation) with high MRI signal intensity. The anlage of the hippocampus is present as a prominent bulging in the thin limbic telencephalon. The early fetal telencephalon impar also contains the first commissural fibers and fornix bundles in the septal area. The ganglionic eminence is clearly visible as an expanded continuation of the proliferative ventricular zone. The basal ganglia showed an ...

2006-02-01

371

Emplacement ages of Jurassic-Cretaceous South African kimberlites by the Rb-Sr method on phlogopite and whole-rock samples  

International Nuclear Information System (INIS)

Rb-Sr phlogopite age determinations, interpreted as emplacement ages, are reported for 15 southern African kimberlites. Jagersfontein and Rietfontein (85 and 95 Ma) have ages typical of the majority of well-known Cretaceous kimberlites, whereas somewhat older ages of about 118 to 125 Ma have been obtained for localities in the Postmasburg, Barkly West and Boshoff districts. Previous zircon ages of 90Ma for Finsch and Roberts Victor are believed to be incorrect. Two other localities in the Barkly West area have significantly younger emplacement ages of about 114 Ma relative to most Barkly West occurrences. Two off-craton kimberlites, Uintjiesberg and Mzongwana, are 100 and 150 Ma in age respectively. Swartruggens and Elandskloof have ages of 150-160 and 165 Ma respectively. A Barkly West occurrence, Klipfontein, also has ...

372

Use of Oral Bisphosphonates by Older Adults with Fractures and Impaired Renal Function  

UK PubMed Central (United Kingdom)

Background:The manufacturers of oral bisphosphonates (alendronate, risedronate) recommend avoiding use of these drugs in patients with renal impairment. However, many patients who...Full Text Available

2011-01-01

373

The role of computed tomography in complex facial trauma  

Energy Technology Data Exchange (ETDEWEB)

Tridimensional localization of bone and soft tissue injuries in complex facial trauma is fundamental for treatment. The face can be conceptualized as 3 groups of interconnected osseous struts that are oriented in the horizontal, sagittal and coronal planes. Each group of struts is closely related to specific soft tissue structures that are susceptible to injury. Any single CT section in the coronal plane or in the axial plane contains parts of one or more these struts. Facial CT in biplane were performed in 32 patients of facial trauma. The most common site of facial fractures is found in middle part of horizontal struts, geometrically in anteromedial portion of the inferior orbital fissure of the face. The most common soft tissue injury combined with facial fracture is hematoma and/or herniated orbital contents into the maxillary sinus. The serious combined soft tissue injuries were ocular rupture, retroorbital hematoma and optic nerve injury ...

1988-02-15

374

Strength and fluoride release characteristics of a calcium fluoride based dental nanocomposite  

UK PubMed Central (United Kingdom)

Secondary caries and restoration fracture remain the two most common problems in restorative dentistry. Release of fluoride ions (F) could be a substantial benefit because F could enrich neighboring...Full Text Available

2008-11-01

375

Satisfaction of Search in Multi-trauma Patients: Severity of Detected Fractures  

UK PubMed Central (United Kingdom)

PurposeSatisfaction of search (SOS) occurs when an abnormality is missed because another abnormality has been detected. This research studied whether the severity...Full Text Available

2007-06-01

376

Optimal bone strength and mineralization requires the type 2 iodothyronine deiodinase in osteoblasts  

UK PubMed Central (United Kingdom)

Hypothyroidism and thyrotoxicosis are each associated with an increased risk of fracture. Although thyroxine (T4) is the predominant circulating thyroid hormone, target cell responses are determined...Full Text Available

2010-04-20

377

Musculoskeletal injuries in an Army airborne population.  

Science.gov (United States)

To maintain operational readiness, military personnel engage in vigorous physical and training activities that carry risk for injury. A 1-year prospective cohort study, starting April 1996, was conducted at Fort Bragg, North Carolina among 1,965 members of the 82nd Airborne Division to quantify musculoskeletal injuries. Information collected included type of injury, site, circumstances, and resultant limited duty days. These soldiers suffered 508 overuse injuries (including 38 stress fractures), 1,415 traumatic injuries (including 100 fractures), and 101 unclassified injuries. Injury rates were 6.8% per soldier per month for traumatic injury and 2.4% for overuse injury (totaling 1.2 injuries per soldier per year). Injuries resulted in 22,041 limited duty days, averaging 11 days per injury and 13 days per soldier (4.5% of total workdays). Fractures and stress fractures/reactions produced the most days ...

2002-12-01

378

Microstructure fracture toughness and fatigue crack growth rate in titanium alloys; Proceedings of the 1987 TMS-AIME Annual Symposium, Denver, CO, Feb. 24, 25, 1987  

Science.gov (United States)

The papers contained in this volume provide an overview of recent theoretical and experimental research related to the fracture toughness and fatigue crack growth characteristics of titanium alloys. Topics discussed include room temperature fatigue crack propagation in beta-titanium alloys, fatigue crack growth rate acceleration in alpha+beta Ti alloys, influence of transformed beta microstructures on fatigue crack growth rates in Ti-6Al-4V, and the role of inclusion and pore content on the fracture toughness of powder processed blended elemental Ti-10V-2Fe-3Al. Papers are also presented on fatigue crack growth measurements in an alpha-beta titanium alloy, the effects of thermal processing variation on the properties of Ti-6Al-4V, and the effect of microstructure on ductility and fracture toughness of alpha+beta titanium alloys.

1987-01-01

379

Intraoral Repair of All Ceramic Fixed Partial Denture Utilizing Preimpregnated Fiber Reinforced Composite  

UK PubMed Central (United Kingdom)

All ceramic fixed partial dentures (FPD)s exhibit enhanced biocompatibility and esthetics as compared to metal-ceramic restorations. However, framework fractures are frequently reported especially when...Full Text Available

2008-01-01

380

Integrated interpretation of AE clusters and fracture system in Hijiori HDR artificial reservoir; Hijiori koon gantai jinko choryuso no AE cluster to kiretsu system ni kansuru togoteki kaishaku  

Energy Technology Data Exchange (ETDEWEB)

With regard to a fracture system in the Hijiori hot dry rock artificial reservoir, an attempt was made on an interpretation which integrates different data. Major factors that characterize development and performance of an artificial reservoir are composed of a fracture system in rocks, which acts as circulating water paths, a heat exchange face and a reservoir space. The system relates not only with crack density distribution, but also with cracks activated by water pressure fracturing, cracks generating acoustic emission (AE), and cracks working as major flow paths, all of which are characterized by having respective behaviors and roles. Characteristics are shown on AE cluster distribution, crack distribution, production zone and estimated stress fields. Mutual relationship among these elements was discussed based on the Coulomb`s theory. The most important paths are characterized by distribution of slippery cracks. ...

1997-05-27

381

Influence of long-time stress relief treatments on the dynamic fracture toughness properties of ASME SA508 C1 2a and ASME SA533 GR B C12 pressure vessel steels  

Energy Technology Data Exchange (ETDEWEB)

Dynamic fracture toughness tests were performed on materials which had been subjected to one of three long-time post weld type stress relief heat treatments: 48 hours at 1000/degree/F (538/degree/C), 24 hours at 1125/degree/F (607/degree/C), and 48 hours at 1125/degree/F (607/degree/C). Linear elastic K/sub Id/ results were obtained at low temperatures while J-integral techniques were utilized to evaluate dynamic fracture toughness over the transition and upper shelf temperature ranges. Tensile, Charpy impact, and drop weight nil-ductility transition tests as well as room temperature, air environment fatigue crack growth rate tests (SA508 Cl 2a only) were also performed. The fracture toughness of both materials exceeded the ASME specified minimum reference toughness K/sub IR/ curve. 17 refs.

1982-03-01

382

Influence of long-time stress relief treatments on the dynamic fracture toughness properties of ASME SA508 C1 2a and ASME SA533 GR B C12 pressure vessel steels  

International Nuclear Information System (INIS)

Dynamic fracture toughness tests were performed on materials which had been subjected to one of three long-time post weld type stress relief heat treatments: 48 hours at 1000/degree/F (538/degree/C), 24 hours at 1125/degree/F (607/degree/C), and 48 hours at 1125/degree/F (607/degree/C). Linear elastic K/sub Id/ results were obtained at low temperatures while J-integral techniques were utilized to evaluate dynamic fracture toughness over the transition and upper shelf temperature ranges. Tensile, Charpy impact, and drop weight nil-ductility transition tests as well as room temperature, air environment fatigue crack growth rate tests (SA508 Cl 2a only) were also performed. The fracture toughness of both materials exceeded the ASME specified minimum reference toughness K/sub IR/ curve. 17 refs.

383

Fracture risk associated with continuation versus discontinuation of bisphosphonates after 5 years of therapy in patients with primary osteoporosis: a systematic review and meta-analysis  

UK PubMed Central (United Kingdom)

Purpose:The risks and benefits of continuing bisphosphonate therapy beyond 5 years in patients with primary osteoporosis have not been well established.Methods:We...Full Text Available

2011-01-01

384

Fracture characteristics obtained from the instrumented impact test of A533B steel for reactor pressure vessel  

Energy Technology Data Exchange (ETDEWEB)

Analyses of the date obtained from the instrumented impact test and of its correlation with static and dynamic J integral values and various tensile properties are made in this study. It is shown that a dynamic bending yield load recorded in the instrumented Charpy V test can be easily converted to a dynamic tensile yield stress using Server's equation. It is also possible to estimate a true fracture strain, COD value, and SZW easily if the load point displacement is recorded. Temperature dependency of Charpy V energy and J integral values is rather well simulated by a curve fitting method. However, a half value transition temperture obtained in that method has no physical meaning. Dynamic J sub(ID) is larger than a static J sub(IC) in the ductile fracture range in this study. This rise is proportional to the yield stress ratio sigmasub(yd)/sigmasub(y)(--1.2-1.3). It is found, therefore, that the following relation exists in the both ...

1983-07-01

385

Fracture characteristics obtained from the instrumented impact test of A533B steel for reactor pressure vessel  

International Nuclear Information System (INIS)

Analyses of the date obtained from the instrumented impact test and of its correlation with static and dynamic J integral values and various tensile properties are made in this study. It is shown that a dynamic bending yield load recorded in the instrumented Charpy V test can be easily converted to a dynamic tensile yield stress using Server's equation. It is also possible to estimate a true fracture strain, COD value, and SZW easily if the load point displacement is recorded. Temperature dependency of Charpy V energy and J integral values is rather well simulated by a curve fitting method. However, a half value transition temperture obtained in that method has no physical meaning. Dynamic J sub(ID) is larger than a static J sub(IC) in the ductile fracture range in this study. This rise is proportional to the yield stress ratio #sigma#sub(yd)/#sigma#sub(y)(--1.2-1.3). It is found, therefore, that the following relation exists in the both cases; ...

386

Fracture behavior of heat-affected zone in low alloy steels  

International Nuclear Information System (INIS)

Past elastic-plastic fracture studies for leak-before-break (LBB) assessment of low alloy steel pipings have been focused mostly on the behavior of base metals and their weld metals. In contrast, the heat-affected zone (HAZ) of a welded pipe has not been studied in detail primarily because the size of the HAZ is too small to make specimens for mechanical properties measurements. In this study, microstructural analyses, microhardness tests, tensile tests and J-R tests have been conducted as a function of distance from a fusion line and temperature for HAZ materials of SA106Gr.C low alloy piping steels. For the ferrite-pearlite steels such as SA106Gr.C, the HAZ specimens showed a higher yield strength and fracture toughness compared with those of its base metal. These characteristics, despite of grain coarsening, can be explained by cleaner microstructures of HAZ materials with a finer morphology of carbides compared with pearlitic-ferritic base ...

2001-11-01

387

Foraminal stenosis complicating retained broken epidural needle tip -A case report-  

UK PubMed Central (United Kingdom)

Lumbar epidural anesthesia is useful in a variety of chronic benign pain syndromes, including lumbar radiculopathy, low back pain syndrome, spinal stenosis, and vertebral compression fractures. Given...Full Text Available

2010-12-01

388

Dietary patterns associated with fall-related fracture in elderly Japanese: a population based prospective study  

UK PubMed Central (United Kingdom)

BackgroundDiet is considered an important factor for bone health, but is composed of a wide variety of foods containing complex combinations of nutrients. Therefore we investigated...Full Text Available

389

Development of multifocal atrial tachycardia in a patient using aminophylline -A case report-  

UK PubMed Central (United Kingdom)

An 82-year-old female, with left femoral neck fracture was scheduled for left hip hemiarthroplasty, under spinal anaesthesia. She had been suffering from diabetes, hypertension, lung cancer and was...Full Text Available

2010-12-01

390

Development and cytotoxicity evaluation of SiAlONs ceramics  

International Nuclear Information System (INIS)

SiAlONs are ceramics with high potential as biomaterials due to their chemical stability, associated with suitable mechanical properties, such as high fracture toughness and fracture resistance. The objective of this work was to investigate the mechanical properties and the cytotoxicity of these ceramic materials. Three different compositions were prepared, using silicon nitride, aluminum nitride and a rare earth oxide mixture as starting powders, yielding Si_3N_4-SiAlON composites or pure SiAlON ceramics, after hot-pressing at 1750 deg. C, for 30 min. The sintered samples were characterized by X-ray diffraction analysis (XRD) and scanning electron microscopy (SEM). Furthermore, hardness and fracture toughness were determined using the Vicker's indentation method. The biological compatibility was evaluated by in vitro cytotoxicity tests. Ceramic with elevated hardness, ranging between 17 and 21 GPa, and high ...

2007-01-01

391

DIFFERENCES IN THE MECHANICAL BEHAVIOR OF CORTICAL BONE BETWEEN COMPRESSION AND TENSION WHEN SUBJECTED TO PROGRESSIVE LOADING  

UK PubMed Central (United Kingdom)

The hierarchical arrangement of collagen and mineral into bone tissue presumabley maximizes fracture resistance with respect to the predominant strain mode in bone. Thus, the ability of cortical...Full Text Available

2009-12-01

392

DEXA as a Predictor of Fixator Removal in Distraction Osteogenesis  

UK PubMed Central (United Kingdom)

Premature removal of the fixator after a lengthening procedure can result in gradual bending or acute fracture of the regenerate. We reviewed the records of 26 patients who underwent 28 limb lengthenings...Full Text Available

2008-12-01

393

Bone stress injury of the ankle in professional ballet dancers seen on MRI  

UK PubMed Central (United Kingdom)

BackgroundBallet Dancers have been shown to have a relatively high incidence of stress fractures of the foot and ankle. It was our objective to examine MR imaging patterns of bone...Full Text Available

394

Biographical Sketch: John Royal Moore, MD 1899?1988  

British Library Electronic Table of Contents (United Kingdom)

This biographical sketch on John R. Moore corresponds to the historic text, The Classic: Cartilaginous-cup Arthroplasty in Ununited Fractures of the Neck of the Femur (1948), available at DOI External Reference Not Shown .

2011-01-01

395

Association of Paraoxonase 1 (PON1) polymorphisms with osteoporotic fracture risk in postmenopausal Korean women  

UK PubMed Central (United Kingdom)

There is increasing evidence of a biochemical link between lipid oxidation and bone metabolism. Paraoxonase 1 (PON1) prevents the oxidation of low-density lipoprotein (LDL) and metabolizes biologically...Full Text Available

2011-02-28

396

Toughened semicrystalline engineering polymers: Morphology, impact resistance, and fracture mechanisms  

Energy Technology Data Exchange (ETDEWEB)

Major factors that contribute to maximized impact resistance of semicrystalline engineering polymers include increased matrix molecular weight, minimal rubber glass-transition temperature, and optimal rubber-particle size, which depends on matrix type. Additional constraints are posed by the limitations of available materials and commercial requirements. Expanding the understanding of impact-modified crystalline engineering polymers will further extend their property ranges and utility. This chapter describes the phenomenology of certain factors, illustrates a new technique to measure rubber particle size, and contrasts the fracture mechanisms of poly(butylene terephthalate), nylon 66, and polyacetal. 49 refs., 24 figs.

1993-12-31

397

Scintigraphic detection of a radiologically equivocal fracture  

Energy Technology Data Exchange (ETDEWEB)

This case report makes evident that in a 75 years old patient with a (cured) femoral neck fracture 15 years ago a refracture at the same site following a new trauma could not be detected by conventional X-ray. The follow-up of a radionuclide bone study, however, enabled the dignosis of a refracture. From these findings, it is further evident that the decreased bone metabolism in older patients has to be considered. Thus, although the initial bone scan following the trauma is negative, a follow-up scan should be performed within a 4 day-period.

1988-04-01

398

Scintigraphic detection of a radiologically equivocal fracture  

International Nuclear Information System (INIS)

This case report makes evident that in a 75 years old patient with a (cured) femoral neck fracture 15 years ago a refracture at the same site following a new trauma could not be detected by conventional X-ray. The follow-up of a radionuclide bone study, however, enabled the dignosis of a refracture. From these findings, it is further evident that the decreased bone metabolism in older patients has to be considered. Thus, although the initial bone scan following the trauma is negative, a follow-up scan should be performed within a 4 day-period. (orig.).

399

Radiology of facial injury  

Energy Technology Data Exchange (ETDEWEB)

The authors present a guide to the imaging of facial fractures. It is illustrated with conventional radiographs and computed tomograms; the magnetic resonance images primarily suggest the potential applications of this technique. This book provides a source of imaging information on facial trauma. A section on pertinent anatomy is followed by a systematic discussion of the common isolated and complex facial fractures. Perspectives are offered on some commonly seen but infrequently described relationships, such as the tripod-LeFort II association. Consideration is also given to related soft-tissue injuries. The book includes a brief chapter on the type and utility of supplementary imaging studies in the evaluation of those intracranial injuries that may occur concurrently.

1988-01-01

400

Probabilistic fracture assessment of surface cracked pipes using strain-based approach  

British Library Electronic Table of Contents (United Kingdom)

Simplified strain-based fracture mechanics equations, established for external surface cracked pipelines subjected to an external bending load, are presented and used in probabilistic assessment of a pipeline girth weld. The model takes into account several parameters, such as variation in crack depth, crack length, internal pressure and material hardening. The critical strain from ductile tearing in the cracked pipeline is found by using the tangency criterion. The reliability problem is solved using first and second order reliability methods for different pipe dimensions and load levels.

2006-01-01

401

Posttraumatic tibia valga: a case demonstrating asymmetric activity at the proximal growth plate on technetium bone scan  

Energy Technology Data Exchange (ETDEWEB)

Posttraumatic tibia valga is a well-recognized complication following fracture of the upper tibial metaphysis in young children. We present a case of a child who developed a valgus deformity following fracture of the proximal tibia and fibula in which quantitative bone scintigraphy at 5 months after injury demonstrated increased uptake at the proximal tibial growth plate with proportionally greater uptake on the medial side. This finding suggests that the valgus deformity in this patient was due to a relative increase in vascularity and consequent overgrowth of the medial portion of the proximal tibial physis.

1987-07-01

402

Posttraumatic tibia valga: a case demonstrating asymmetric activity at the proximal growth plate on technetium bone scan  

International Nuclear Information System (INIS)

Posttraumatic tibia valga is a well-recognized complication following fracture of the upper tibial metaphysis in young children. We present a case of a child who developed a valgus deformity following fracture of the proximal tibia and fibula in which quantitative bone scintigraphy at 5 months after injury demonstrated increased uptake at the proximal tibial growth plate with proportionally greater uptake on the medial side. This finding suggests that the valgus deformity in this patient was due to a relative increase in vascularity and consequent overgrowth of the medial portion of the proximal tibial physis.

403

Extrinsic fracture mechanisms in two laminated metal composites  

Energy Technology Data Exchange (ETDEWEB)

The crack growth behavior and fracture toughness of two laminated metal composites (6090/SiC/25p laminated with 5182 and ultrahigh-carbon steel laminated with brass) have been studied in both ``crack arrester`` and ``crack divider`` orientations. The mechanisms of crack growth were analyzed and extrinsic toughening mechanisms were found to contribute significantly to the toughness. The influence of laminate architecture (layer thickness and component volume function), component material properties and residual stress on these mechanisms and the resulting crack growth resistance are discussed.

1994-11-29

404

Ewing's sarcoma of the humerus mimicking fibrous dysplasia on imaging and biological behavior  

International Nuclear Information System (INIS)

We present the case of a 12-year-old girl who presented with a pathological fracture through a benign-appearing osteolytic lesion that was presumed to represent fibrous dysplasia. The fracture healed, and over the next 2.5 years there was further refracturing and healing with progressive osteolysis. A biopsy was performed and revealed Ewing's sarcoma. The disease was locally controlled by neoadjuvant chemotherapy and radiation therapy. The patient is disease free with excellent function 6 years following the discovery of the lesion. We illustrate and discuss the sequence of events. (orig.)

2005-05-01

405

Evaluation of ultrasonic indications in steam turbine rotors by fracture mechanics analysis  

International Nuclear Information System (INIS)

The report summarizes ten years of experience in the analysis and evaluation of ultrasonic testing data measured in turbine and generator rotors. Apart from the information on type, position, size and distribution of flaws, the expert knowledge achieved in an interpretation of ultrasonic signals yields further insight, as e.g.: - Confirmation of assumptions taken as a basis for fracture-mechanical analysis of these flaws with regard to crack initiation and crack growth under low-cycle fatigue conditions (O=0.7-1 Rp 0.2, N<25.000 growth in length); - enhanced information on a correlation of ultrasonic testing data with the real flaw size. (orig.).

1990-10-04

406

Effect of yttrium on mechanical properties of 9Cr-2WVTa low active martensite steel  

International Nuclear Information System (INIS)

The effect of the rare earth element, yttrium, on the mechanical properties of 9Cr-2WVTa low active martensite steel for fusion reactor was studied and the metallurgical behavior of yttrium in the steel was primarily analyzed. The results show that it is easy for yttrium to aggregate and form the blocky yttrium rich inclusions in the steel, which can dissever the continuity of the matrix and produce micro-cracks for fracture. The yttrium rich inclusions were distributed along the rolling direction, which made the fracture surface delaminated in the tensile and impact samples, and reduced the mechanical properties of the steel. (authors)

2009-03-01

407

Effect of grain size and pearlite morphology on the components of the fracture energy in steel 45 in the region of the ductile-brittle transition  

Energy Technology Data Exchange (ETDEWEB)

It is known that in size reduction of the granular structure of ferrite and ferrite-pearlite steels the temperature of the transformation from ductile to brittle condition is lowered. This effect can also be caused by an increase in the dispersity of intragrain and intergrain segregations (sulfides, carbonitrides, and segregations of impurity atoms), which accompanies grain size reduction and promotes initiation and propagation of cracks. In order to clarify the mechanism of fracture of steel in the region of the ductile-brittle transition steel 45 with different grain sizes and pearlite morphologies has been investigated.

1995-11-01

408

Brittle fracture problem in composite insulators  

Energy Technology Data Exchange (ETDEWEB)

The report traces the documented incidences of brittle fracture in composite suspension insulators for use on high voltage transmission lines, and presents the subsequent investigations. It describes the part played by electrical activity, stress corrosion and humidity, and compares similar failures that have taken place in electric traction insulators. It then goes on to review related work on the humidity effects, stress corrosion, fatigue and partial discharges in glass fiber reinforced plastics in general. The final section summarizes the present understanding of the problem and the various measures taken by different manufactures to avoid it in the future. The need for acceptance criteria in this respect is outlined.

1984-04-01

409

Geological evolution of the center-southern portion of the Guyana shield based on the geochemical, geochronological and isotopic studies of paleoproterozoic granitoids from southeastern Roraima, Brazil; Evolucao geologica da porcao centro-sul do escudo das Guianas com base no estudo geoquimico, geocronologico e isotopico dos granitoides paleoproterozoicos do sudeste de Roraima, Brasil  

Energy Technology Data Exchange (ETDEWEB)

This study focuses the granitoids of center-southern portion of Guyana Shield, southeastern Roraima, Brazil. The region is characterized by two tectonic-stratigraphic domains, named as Central Guyana (GCD) and Uatuma-Anaua (UAD) and located probably in the limits of geochronological provinces (e.g. Ventuari-Tapajos or Tapajos-Parima, Central Amazonian and Maroni-Itacaiunas or Transamazon). The aim this doctoral thesis is to provide new petrological and lithostratigraphic constraints on the granitoid rocks and contribute to a better understanding of the origin and geo dynamic evolution of Guyana Shield. The GCD is only locally studied near to the UAD boundary, and new geological data and two single zircon Pb-evaporation ages in mylonitic biotite granodiorite (1.89 Ga) and foliated hastingsite-biotite granite (1.72 Ga) are presented. These ages of the protholiths contrast with the lithostratigraphic picture in the other areas of Cd (1.96-1.93 ...

2006-07-01

410

The prevalence and correlates of self-reported hearing impairment in the Ibadan Study of Ageing  

UK PubMed Central (United Kingdom)

AbstractThis cohort study of 1302 persons aged ≥65 years, conducted in the Yoruba-speaking regions of Nigeria, determines the prevalence and correlates of hearing impairment (HI)...Full Text Available

2010-08-01

411

The implication of Sir2 in replicative aging and senescence in Saccharomyces cerevisiae  

UK PubMed Central (United Kingdom)

The target of rapamycin (TOR) pathway regulates cell growth and aging in various organisms. In Saccharomyces cerevisiae, silent information regulator 2 (Sir2) modulates cellular senescence. Moreover,...Full Text Available

412

The first long-lived mutants: discovery of the insulin/IGF-1 pathway for ageing  

UK PubMed Central (United Kingdom)

Inhibiting insulin/IGF-1 signalling extends lifespan and delays age-related disease in species throughout the animal kingdom. This life-extension pathway, the first to be defined, was discovered through...Full Text Available

2011-01-12

413

The effects of androgens and gonadotropins on testicular development in the prepubertal rat.  

UK PubMed Central (United Kingdom)

Treatment of male rat pups from five to 34 days of age with dihydrotestosterone or 5 alpha-androstane-3 alpha, 17 beta-diol, resulted in reduced testicular size at 35 days of age. This appeared to be...Full Text Available

1985-07-01

414

The Aging Heart and Post-Infarction Left Ventricular Remodeling  

UK PubMed Central (United Kingdom)

Aging is a risk factor for heart failure, which is a leading cause of death world-wide. Elderly patients are more likely than young patients to experience a myocardial infarction (MI) and are...Full Text Available

2010-12-28

415

Survey on Aging Deterioration of Safety Related Equipment in Operating Nuclear Power Plants  

International Nuclear Information System (INIS)

As a basic research to consider aging deterioration of the operating nuclear power plant to seismic fragility analysis, aging deteriorations occurring safety related equipment of both Kori unit 1 and Wolsung unit 1, are investigated in this study. First of all, 378 and 152 safety related equipment are selected at Kori unit 1 and Wolsung unit 1 respectively. Seismic review team including seismic capability engineer, is organized and seismic walkdown is carried out using the nondestructive tests. As a results of seismic walkdown, crack is a typical aging deterioration which can reduce the seismic safety of safety related equipment and the other aging deteriorations such as concrete compressive strength, corrosion, and tightness of anchor bolt, have a much smaller influence than crack. In order to manage the aging deterioration data collected through the seismic walkdown in effective ...

1997-04-14

416

Survey on Aging Deterioration of Safety Related Equipment in Operating Nuclear Power Plants  

Energy Technology Data Exchange (ETDEWEB)

As a basic research to consider aging deterioration of the operating nuclear power plant to seismic fragility analysis, aging deteriorations occurring safety related equipment of both Kori unit 1 and Wolsung unit 1, are investigated in this study. First of all, 378 and 152 safety related equipment are selected at Kori unit 1 and Wolsung unit 1 respectively. Seismic review team including seismic capability engineer, is organized and seismic walkdown is carried out using the nondestructive tests. As a results of seismic walkdown, crack is a typical aging deterioration which can reduce the seismic safety of safety related equipment and the other aging deteriorations such as concrete compressive strength, corrosion, and tightness of anchor bolt, have a much smaller influence than crack. In order to manage the aging deterioration data collected through the seismic walkdown in effective ...

2008-02-15

417

Studies of osteoporosis in Singapore using isotope-related techniques  

International Nuclear Information System (INIS)

The main objectives of this study was to determine the bone density for the purposes of i) determining the age of peak bone mass in each study group and ii) quantifying the differences in bone density as functions of age and sex. The results of estimating the age dependence of mineral density for the femoral neck, spine and total body of healthy women and men using DEXA are given. The age changes in concentrations of major minerals and electrolytes found for compact and trabecular bones of healthy male femoral neck with regard for the wet and dry tissue calculations are represented. Information about femoral neck water content depending on the age of healthy men is tabulated. The number of performed observations and analyses is evidently insufficient to make any final decision, however some preliminary conclusions can be drawn. In accordance with DEXA results, BMD maximum for the ...

1996-10-07

418

Some highlights of research on aging with invertebrates, 2010  

UK PubMed Central (United Kingdom)

This annual review focuses on invertebrate model organisms, which continue to yield fundamental new insights into mechanisms of aging. This year, the budding yeast has been used to understand how asymmetrical...Full Text Available

2011-02-01

419

Socio-demographic and health-related factors associated with cognitive impairment in the elderly in Taiwan  

UK PubMed Central (United Kingdom)

BackgroundCognitive impairment is an age-related condition as the rate of cognitive decline rapidly increases with aging. It is especially important to better understand factors...Full Text Available

420

SirT1 brings stemness closer to cancer and aging  

UK PubMed Central (United Kingdom)

Sirtuin 1 acts in various cell processes, deacetylating both chromatin and non-histone proteins, and its role in cancer and aging has long been studied and debated. Here we discuss another aspect of...Full Text Available

421

RasGrf1 deficiency delays aging in mice  

UK PubMed Central (United Kingdom)

RasGRF1 is a Ras-guanine nucleotide exchange factor implicated in a variety of physiological processes including learning and memory and glucose homeostasis. To determine the role of RASGRF1 in aging,...Full Text Available

422

Quantitative bone scintigraphy in children and adolescents. Age dependence of skeleton uptake  

International Nuclear Information System (INIS)

French ... Orig. Title Scintigraphie osseuse quantifiee chez l'enfant et l'adolescent - repartition selon l'age des taux de fixation de diverses pieces osseuses normales.

423

Pulsars - survey of observational data  

Energy Technology Data Exchange (ETDEWEB)

The paper reviews the main observational data on pulsars, both the individual characteristics of pulsars and the properties they possess as members of the Galaxy. Consideration is then given to pulsar ages and to pulsar initial periods. An attempt is made to clarify the 'true' ages of pulsars.

1980-01-01

424

Protein stability and resistance to oxidative stress are determinants of longevity in the longest-living rodent, the naked mole-rat  

UK PubMed Central (United Kingdom)

The widely accepted oxidative stress theory of aging postulates that aging results from accumulation of oxidative damage. Surprisingly, data from the longest-living rodent known, naked mole-rats [MRs;...Full Text Available

2009-03-03

425

Physical Activity and Telomere Biology: Exploring the Link with Aging-Related Disease Prevention  

UK PubMed Central (United Kingdom)

Physical activity is associated with reduced risk of several age-related diseases as well as with increased longevity in both rodents and humans. Though these associations are well established, evidence...Full Text Available

426

Oxidative Stress and Longevity in Okinawa: An Investigation of Blood Lipid Peroxidation and Tocopherol in Okinawan Centenarians  

UK PubMed Central (United Kingdom)

Background. The Free Radical Theory of Aging mechanistically links oxidative stress to aging. Okinawa has among the world's longest-lived populations but oxidative stress in this...Full Text Available

2010-01-01

427

Opposing function of mitochondrial prohibitin in aging  

UK PubMed Central (United Kingdom)

While specific signalling cascades involved in aging, such as the insulin/IGF-1 pathway, are well-described, the actual metabolic changes they elicit to prolong lifespan remain obscure. Nevertheless,...Full Text Available

428

Natural variation in life history and aging phenotypes is associated with mitochondrial DNA deletion frequency in Caenorhabditis briggsae  

UK PubMed Central (United Kingdom)

BackgroundMutations that impair mitochondrial functioning are associated with a variety of metabolic and age-related disorders. A barrier to rigorous tests of the role of mitochondrial...Full Text Available

429

Mutation analysis of the ferritin L-chain gene in age-related cataract  

UK PubMed Central (United Kingdom)

PurposeTo investigate whether acquired somatic mutations in the iron response element of the ferritin L-chain gene account for the age-related cataract.MethodsThe...Full Text Available

430

Mechanisms of chemotherapy-induced human ovarian aging: double strand DNA breaks and microvascular compromise  

UK PubMed Central (United Kingdom)

The mechanism of chemotherapy-induced acceleration of ovarian aging is not fully understood. We used doxorubicin, a widely used cancer chemotherapeutic, in a variety of in vivo xenograft,...Full Text Available

431

Interrelationships between ambient temperature, age at calving, postpartum reproductive events and reproductive performance in dairy cows: a path analysis.  

UK PubMed Central (United Kingdom)

Path analysis was used to determine the interrelationships between ambient temperature, age at calving, postpartum reproductive events and reproductive performance in dairy cows. The data used in the...Full Text Available

1985-07-01

432

Increased superoxide in vivo accelerates age-associated muscle atrophy through mitochondrial dysfunction and neuromuscular junction degeneration  

UK PubMed Central (United Kingdom)

Oxidative stress has been implicated in the etiology of age-related muscle loss (sarcopenia). However, the underlying mechanisms by which oxidative stress contributes to sarcopenia have not been thoroughly...Full Text Available

2010-05-01

433

Hormone Receptor Status in Breast Cancer and its Relation to Age and Other Prognostic Factors  

UK PubMed Central (United Kingdom)

Background:Increasing evidence shows the importance of young age, estrogen receptor (ER), progesterone receptor (PR) status, and HER-2 expression in patients with breast cancers.Patients...Full Text Available

434

Hierarchical and serial processing in the spatial auditory cortical pathway is degraded by natural aging  

UK PubMed Central (United Kingdom)

The compromised abilities to localize sounds and to understand speech are two hallmark deficits in aged individuals. The auditory cortex is necessary for these processes, yet we know little...Full Text Available

2010-11-03

435

Heat Stress and Hormetin-Induced Hormesis in Human Cells: Effects on Aging, Wound Healing, Angiogenesis, and Differentiation  

UK PubMed Central (United Kingdom)

Accumulation of molecular damage and increased molecular heterogeneity are hallmarks of cellular aging. Mild stress-induced hormesis can be an effective way for reducing the accumulation of molecular...Full Text Available

436

Handgrip dynamometry, Cybex measurements and lean mass as markers of the ageing of muscle function.  

UK PubMed Central (United Kingdom)

Isometric handgrip force, isokinetic knee flexion and extension torque, and anthropometric data were obtained on 67 older men and women (ranging in age from 45 to 75 years, mean 59.7 years). Hydrostatic...Full Text Available

1991-12-01

437

Gender differences in metformin effect on aging, life span and spontaneous tumorigenesis in 129/Sv mice  

UK PubMed Central (United Kingdom)

Studies in mammals have led to the suggestion that hyperglycemia and hyperinsulinemia are important factors both in aging and in the development of cancer. It is possible that the life-prolonging effects...Full Text Available

438

Female rats display dose-dependent differences to the rewarding and aversive effects of nicotine in an age-, hormone-, and sex-dependent manner  

UK PubMed Central (United Kingdom)

IntroductionThe objective of this study was to examine age-, hormone-, and sex-dependent differences to the behavioral effects of nicotine using place-conditioning...Full Text Available

2009-10-01

439

Embryonic anti-aging niche  

UK PubMed Central (United Kingdom)

Although functional organ stem cells persist in the old, tissue damage invariably overwhelms tissue repair, ultimately causing the demise of an organism. The poor performance of stem cells in an aged...Full Text Available

440

Effects of old age on vascular complexity and dispersion of the hepatic sinusoidal network  

UK PubMed Central (United Kingdom)

ObjectivesIn old age, there are marked changes in both the structure of the liver sinusoidal endothelial cell and liver perfusion. The objective of this study was...Full Text Available

2008-04-01

441

Effects of gender, age, diabetes mellitus and renal and hepatic impairment on tadalafil pharmacokinetics  

UK PubMed Central (United Kingdom)

AimsTo evaluate the effects of gender, age, diabetes mellitus, renal and hepatic impairment on tadalafil pharmacokinetics and tolerability.MethodsSix...Full Text Available

2007-01-01

442

Effects of Age on Optical Coherence Tomography Measurements of Healthy Retinal Nerve Fiber Layer, Macula and Optic Nerve Head  

UK PubMed Central (United Kingdom)

PurposeTo determine the effects of age on global and sectoral peripapillary retinal nerve fiber layer (RNFL), macular thicknesses and optic nerve head (ONH) parameters...Full Text Available

2009-06-01

443

Effect of hypophysectomy on liver nuclear ribonucleic acid synthesis in aging rats.  

UK PubMed Central (United Kingdom)

Changes in RNA synthesis in liver nuclei were observed at different ages and after hypophysectomy and hormone replacement in female Sprague-Dawley rats. As determined by the incorporation of [3H]UMP...Full Text Available

1979-12-15

444

Does Damage to DNA and Other Macromolecules Play a Role in Aging? If So, How?  

UK PubMed Central (United Kingdom)

One of the most pervasive ideas regarding the causes of aging is that longevity is constrained in large measure by damage to macromolecules. An increasing body of cellular and molecular data, generated...Full Text Available

2009-02-01

445

Diverging trends in incidence and mortality of testicular cancer in Denmark, 1943-1982.  

UK PubMed Central (United Kingdom)

Between 1943 and 1982, 5,140 new cases of testicular cancer were diagnosed in Denmark. The age-standardized incidence rate more than doubled in the period. Striking variations is seen in the age-relationship...Full Text Available

1986-04-01

446

Demographics, aging and health care: is there a crisis?  

UK PubMed Central (United Kingdom)

Will the aging of Canada's population bankrupt the health care system? In this issue (see pages 1555 to 1560) Dr. Marie Demers reports that the increase in physician service costs for elderly people...Full Text Available

1996-12-01

447

Deficiency of circadian protein CLOCK reduces lifespan and increases age-related cataract development in mice  

UK PubMed Central (United Kingdom)

Circadian clock is implicated in the regulation of aging. The transcription factor CLOCK, a core component of the circadian system, operates in complex with another circadian clock protein BMAL1. Recently...Full Text Available

448

Cumulative Inflammatory Load Is Associated with Short Leukocyte Telomere Length in the Health, Aging and Body Composition Study  

UK PubMed Central (United Kingdom)

BackgroundLeukocyte telomere length (LTL) is an emerging marker of biological age. Chronic inflammatory activity is commonly proposed as a promoter of ...Full Text Available

449

Correspondence of Ultrasound Elasticity Imaging to Direct Mechanical Measurement in Aging DVT in Rats  

UK PubMed Central (United Kingdom)

Previous ultrasound elasticity imaging experiments supported a generally accepted concept that the hardness of deep venous thrombi increases with thrombus aging. Results also showed that this...Full Text Available

2005-10-01

450

Cell kinetics of growth cartilage of achondroplastic (cn) mice.  

UK PubMed Central (United Kingdom)

Mice homozygous for the recessive gene achondroplasia (cn) aged 16 and 17 days and some homozygotes aged 22-34 days have disruptions in the growth of the proximal tibial growth plate which are due solely...Full Text Available

1985-05-01

451

Caveolin-1 as a Novel Indicator of Wound-Healing Capacity in Aged Human Corneal Epithelium  

UK PubMed Central (United Kingdom)

Excess caveolin-1 has been reported to play a role in age-dependent hyporesponsiveness to growth factors in vitro. Therefore, we hypothesized that caveolin-1–dependent hyporesponsiveness...Full Text Available

2010-11-01

452

CYP17 MspA1 Polymorphism and Age at Menarche: a Meta-Analysis  

UK PubMed Central (United Kingdom)

ObjectiveLiterature data on the effects of CYP17 MspA1 polymorphism on age at menarche (AAM) are inconsistent. To reexamine this controversy, we...Full Text Available

2008-01-01

453

Association between hair mineral and age, BMI and nutrient intakes among Korean female adults  

UK PubMed Central (United Kingdom)

This study was performed to investigate the association between hair mineral levels and nutrient intakes, age, and BMI in female adults who visited a woman's clinic located in Seoul. Dietary intakes...Full Text Available

2009-01-01

454

Antioxidant enzyme activities are not broadly correlated with longevity in 14 vertebrate endotherm species  

UK PubMed Central (United Kingdom)

The free radical theory of ageing posits that accrual of oxidative damage underlies the increased cellular, tissue and organ dysfunction and failure associated with advanced age. In support of this...Full Text Available

2010-06-01

455

Aging of the Hair Follicle Pigmentation System  

UK PubMed Central (United Kingdom)

Skin and hair phenotypes are powerful cues in human communication. They impart much information, not least about our racial, ethnic, health, gender and age status. In the case of the latter parameter,...Full Text Available

2009-07-01

456

Aging and the Social Cognitive Determinants of Physical Activity Behavior and Behavior Change: Evidence from the Guide to Health Trial  

UK PubMed Central (United Kingdom)

Part one of this study investigated the effect of aging on social-cognitive characteristics related to physical activity (PA) among adults in the baseline phase of a health promotion...Full Text Available

457

Age-Related Differences in Naturally Acquired T Cell Memory to Plasmodium falciparum Merozoite Surface Protein 1  

UK PubMed Central (United Kingdom)

Naturally acquired immunity to Plasmodium falciparum malaria in malaria holoendemic areas is characterized by the gradual, age-related development of protection against high-density...Full Text Available

458

Age-Related Deterioration of Rod Vision in Mice  

UK PubMed Central (United Kingdom)

Even in healthy individuals, aging leads to deterioration in visual acuity, contrast sensitivity, visual field, and dark adaptation. Little is known about the neural mechanisms that drive the...Full Text Available

2010-08-18

459

Age affects over-marking of opposite-sex scent marks in meadow voles, Microtus pennsylvanicus  

UK PubMed Central (United Kingdom)

Models of age-related effects on behavior predict that among short-lived species younger adults are more attractive and attracted to opposite-sex conspecifics than are older adults, whereas...Full Text Available

2010-01-01

460

Accumulation of Long-Chain Glycosphingolipids during Aging Is Prevented by Caloric Restriction  

UK PubMed Central (United Kingdom)

BackgroundChronic kidney disease and end-stage renal disease are major causes of morbidity and mortality that are seen far more commonly in the aged population. Interestingly, kidney...Full Text Available

461

A Decline in p38 MAPK Signaling Underlies Immunosenescence in Caenorhabditis elegans  

UK PubMed Central (United Kingdom)

The decline in immune function with aging, known as immunosenescence, has been implicated in evolutionarily diverse species, but the underlying molecular mechanisms are not understood. During aging...Full Text Available

2011-05-01

462

Sequential changes in the femoral head after intracapsular fracture of the femoral neck. MRI findings  

International Nuclear Information System (INIS)

Authors obtained T1-weighted MRI images of the femoral head after fracture of the femoral neck and classified the signals into four patterns to investigate the sequential changes of the femoral head. The T1-weighted MRI images obtained initially after femoral neck fracture showed a normal pattern in 10 of the 15 hip joints studied. MRI images obtained subsequently still showed the normal signal pattern in eight of the 10 hip joints which had shown the normal pattern in the first MRI, while two of the 10 joints subsequently showed a band pattern. The joint with the homogeneous pattern in the first MRI subsequently showed a band pattern. Of the three joints with an inhomogeneous pattern in the first MRI, two joints showed a subsequent band pattern, and the other a normal pattern. The joints which showed a band pattern continued to show a similar band pattern. Eventually, all hip joints studied showed a normal or band pattern within six months ...

1998-07-01

463

SR 97 - Alternative models project. Discrete fracture network modelling for performance assessment of Aberg  

Energy Technology Data Exchange (ETDEWEB)

As part of studies into the siting of a deep repository for nuclear waste, Swedish Nuclear Fuel and Waste Management Company (SKB) has commissioned the Alternative Models Project (AMP). The AMP is a comparison of three alternative modeling approaches for geosphere performance assessment for a single hypothetical site. The hypothetical site, arbitrarily named Aberg is based on parameters from the Aespoe Hard Rock Laboratory in southern Sweden. The Aberg model domain, boundary conditions and canister locations are defined as a common reference case to facilitate comparisons between approaches. This report presents the results of a discrete fracture pathways analysis of the Aberg site, within the context of the SR 97 performance assessment exercise. The Aberg discrete fracture network (DFN) site model is based on consensus Aberg parameters related to the Aespoe HRL site. Discrete fracture pathways are identified from canister ...

1999-08-01

464

Greater Green River Basin production improvement project, Phase 1: Site characterization report  

Energy Technology Data Exchange (ETDEWEB)

Several tight, naturally-fractured, gas-productive formations in the Greater Green River Basin (GGRB) in Wyoming have been exploited using conventional vertical well technology. Typically, hydraulic fracture treatments must be performed in completing these wells to increase gas production rates to economic levels. However, with the maturation of horizontal drilling technology hydraulic fracture treatments may not be the most effective method for improving gas production from these tight reservoirs. Two of the most prolific tight gas reservoirs in the Green River Basin, the Frontier and the Mesaverde, are candidates for the application of horizontal well completion technology. The objective of the proposed project is to apply the DOE`s technical concept to the Second Frontier Formation on the western flank of the Rock Springs Uplift. Previous industry attempts to produce in commercial quantities from the Second Frontier ...

1996-05-01

465

Crack growth rates and fracture toughness of irradiated austenitic stainless steels in BWR environments.  

Energy Technology Data Exchange (ETDEWEB)

In light water reactors, austenitic stainless steels (SSs) are used extensively as structural alloys in reactor core internal components because of their high strength, ductility, and fracture toughness. However, exposure to high levels of neutron irradiation for extended periods degrades the fracture properties of these steels by changing the material microstructure (e.g., radiation hardening) and microchemistry (e.g., radiation-induced segregation). Experimental data are presented on the fracture toughness and crack growth rates (CGRs) of wrought and cast austenitic SSs, including weld heat-affected-zone materials, that were irradiated to fluence levels as high as {approx} 2x 10{sup 21} n/cm{sup 2} (E > 1 MeV) ({approx} 3 dpa) in a light water reactor at 288-300 C. The results are compared with the data available in the literature. The effects of material composition, irradiation dose, and water chemistry on CGRs ...

2008-01-21

466

Comparison of CT and MRI in patients with tibial plateau fracture: can CT findings predict ligament tear or meniscal injury?  

Energy Technology Data Exchange (ETDEWEB)

(1) To determine the accuracy of computed tomography (CT) in the evaluation of ligament tear and avulsion in patients with tibial plateau fracture. (2) To evaluate whether the presence or severity of fracture gap and articular depression can predict meniscal injury. A fellowship-trained musculoskeletal radiologist retrospectively reviewed knee CT and MRI examinations of 41 consecutive patients presenting to a level 1 trauma center with tibial plateau fractures. Fracture gap, articular depression, ligament tear and footprint avulsions were assessed on CT examinations. The MRI studies were examined for osseous and soft tissue injuries, including meniscal tear, meniscal displacement, ligament tear, and ligament avulsion. CT demonstrated torn ligaments with 80% sensitivity and 98% specificity. Only 2% of ligaments deemed intact on careful CT evaluation had partial or complete tears on MRI. Although the ...

2007-02-15

469

Contact Lenses  

Medline Plus

... Precautions Comprehensive Eye and Vision Examination Nutrition Lutein Antioxidants & Age-Related Eye Disease Lutein and Zeaxanthin - Eye- ...

472

Age determination of plutonium material in nuclear forensics by thermal ionisation mass spectrometry  

International Nuclear Information System (INIS)

Age is a key parameter when deducing the history of plutonium material, i.e. the plutonium produced in the nuclear reactors. This is of vital importance, when a smuggled plutonium sample has been seized and the origin has to be determined. A methodology is described which allows accurately to determine the age of plutonium material by thermal ionisation mass spectrometry using independent parent/daughter relations. This has been demonstrated for Reference Materials of known ages as well as for real samples. The already established method using gamma spectrometry is compared to this. (orig.)

2000-02-01

473

Accelerated aging tests for radiation degradation of organic materials  

International Nuclear Information System (INIS)

(Jun 1984). United States Clough, RL Gillen, KT Sandia Nat'l Laboratories

1984-06-03

474

[The indicators of biological age and accelerated aging in liquidators of the consequences of radiation emergency].  

Science.gov (United States)

The biological age (BA) of the majority of the liquidators of the consequences of the radiation accidents in the Navy and of the liquidators of the Chernobyl' APS accident exceeds the medium standard and the DBA (due BA). The index of the BA can be a characteristic of the influence of the social-hygienic factors on the health condition of the Special Risk Subunit--the liquidators of the consequences of the radiation accidents. It was established, that the radiation influence concerns to the factors dramatically increasing the BA and the rate of senescence of the liquidators of the consequences of the radiation accidents. PMID:21809627

2011-01-01

475

Long term accelerated aging tests on distribution cables under wet conditions  

Energy Technology Data Exchange (ETDEWEB)

Two accelerated aging test procedures are proposed for use on solid dielectric extruded distribution cables under wet conditions. One test method is a fixed time duration test in which the degree of cable specimen aging is assessed in terms of breakdown tests, while the other test method is a time to breakdown test in which the cable specimens are voltage stressed until failure ensues.

1996-10-01

476

Fundamental understanding of aging processes Review of the workshop results  

CERN Document Server

A study on the aging process of gas detectors was presented. How the development of more performing but delicate detectors, the use of faster but aggressive gases, and the need to cover large areas, led to unexpected problems was discussed. Various methods for curing aged detectors were also highlighted. (Edited abstract) 37 Refs.

2003-01-01

477

Evaluation of an eastern shale oil residue as an asphalt additive  

Energy Technology Data Exchange (ETDEWEB)

An evaluation of eastern shale oil (ESO) residue as an asphalt additive to reduce oxidative age-hardening and moisture susceptibility was conducted. Rheological and infrared analyses of the unaged and aged asphalts and blends were then conducted to evaluate oxidative age-hardening. 18 refs., 5 figs., 6 tabs.

1996-11-01

478

Evaluation of an eastern shale oil residue as an asphalt additive  

Energy Technology Data Exchange (ETDEWEB)

An evaluation of eastern shale oil (ESO) residue as an asphalt additive to reduce oxidative age hardening and moisture susceptibility was conducted by Western Research Institute (WRI). The ESO residue, have a viscosity of 23.9 Pa{lg_bullet}s at 60{degree}C (140{degree}F), was blended with three different petroleum-derived asphalts, ASD-1, AAK-1, and AAM-1, which are known to be very susceptible to oxidative aging. Rheological and infrared analyses of the unaged and aged asphalts and the blends were then conducted to evaluate oxidative age hardening. In addition, the petroleum-derived asphalts and the blends were coated onto three different aggregates, Lithonia granite (RA), a low-absorption limestone (RD), and a siliceous Gulf Coast gravel (RL), and compacted into briquettes. Successive freeze-thaw cycling was then conducted to evaluate the moisture susceptibility of the prepared briquettes. The ...

1995-09-01

479

Development of technical information basis of aging management for nuclear power plants  

International Nuclear Information System (INIS)

In order to implement effective safety regulations on aging management for reactor facilities etc., the information on important technology issues, the latest technical knowledge including evaluation technology, test and research outcomes, related codes and standards, regulation information, operation experiences such as accidents and trouble, etc. with respect to aging-induced deterioration in and outside Japan and in other industries, were collected, organized and evaluated. (author)

2007-08-01

480

Carbide transformations in a gamma/gamma-prime nickel alloy during prolonged aging  

Energy Technology Data Exchange (ETDEWEB)

Carbide reactions occurring in a precipitation-hardening gamma/gamma-prime Ni-Cr alloy during prolonged high-temperature aging are investigated experimentally. It is found that the decomposition of primary MC carbides, which is accompanied by the precipitation of M23C6 particles, may lead to void nucleation and growth. The effect of carbide transformations on the residual properties of the material at temperatures above the equicohesion temperature is observed at the late stages of aging only. 6 references.

1988-08-01

481

Accelerated aging tests with a resid hydrotreating catalyst  

International Nuclear Information System (INIS)

The author discusses the accelerated aging tests performed using Hondo and Maya as aging resids with a commercial large pore hydrotreating catalyst. The results from these tests were compared with those obtained under a normal full life test. The test resid was a sample of a typical refinery charge and the activities for sulfur and vanadium removal were determined at 720"0F after successive brief periods of exposure to the heavier oils.

1988-12-02

482

The influence of normal human ageing on automatic movements  

British Library Electronic Table of Contents (United Kingdom)

There is evidence that aged normal subjects have more difficulty in achieving automaticity than young subjects. The underlying central neural mechanism for this phenomenon is unclear. In the present study, functional magnetic resonance imaging (fMRI) was used to investigate the effect of normal ageing on automaticity. Aged healthy subjects were asked to practice self-initiated, self-paced, memorized sequential finger movements with different complexity until they could perform the tasks automatically. Automaticity was evaluated by having subjects perform a secondary task simultaneously with the sequential movements. Although it took more time, most aged subjects eventually performed the tasks automatically at the same level as the young subjects. Functional MRI results showed that, for bot...

2005-01-01

483

The effects of physical activity, education, and body mass index on the aging brain  

British Library Electronic Table of Contents (United Kingdom)

Abstract Normal human aging is accompanied by progressive brain tissue loss and cognitive decline; however, several factors are thought to influence brain aging. We applied tensor-based morphometry to high-resolution brain MRI scans to determine whether educational level or physical activity was associated with brain tissue volumes in the elderly, particularly in regions susceptible to age-related atrophy. We mapped the 3D profile of brain volume differences in 226 healthy elderly subjects (130F/96M; 77.9 3.6 SD years) from the Cardiovascular Health Study-Cognition Study. Statistical maps revealed the 3D profile of brain regions whose volumes were associated with educational level and physical activity (based on leisure-time energy expenditure). After controlling for age, sex, and physical...

2011-01-01

484

Proterozoic kimberlites and lamproites and a preliminary age for the Argyle lamproite pipe, Western Australia  

International Nuclear Information System (INIS)

The Argyle pipe occurring in the East Kimberley Province of Western Australia is a unique, highly-diamondiferous lamproite. Although it resembles other lamproites located in the West Kimberley Province with respect to its setting, structure, petrography and geochemistry, it is probably Proterozoic in age and hence substantially older than Tertiary occurrences of the West Kimberley Province. Rb-Sr measurements on whole rock and phlogopite samples from magmatic olivine-phlogopite lamproite, reveals a two point model age of 1126 +- 9 Ma for the Argyle pipe. This age is consistent with ages of other, similar volcanic igneous rocks occurring in several localities worldwide. The widespread occurrence of Proterozoic kimberlites and lamproites suggests that this was an important period of worldwide alkalic intrusive activity.

485

Memory of multiple aging stages above the freezing temperature in the Relaxor ferroelectric PLZT.  

Science.gov (United States)

The dynamic dielectric susceptibility and the elastic compliance of the relaxor ferroelectric lanthanum lead zirconate titanate (PLZT) 9/65/35 have been measured under different cooling and heating protocols in order to study aging and memory. The memory of multiple aging stages at different temperatures has been found (several dips in the susceptibility curves on heating), as in spin glass systems below the glass transition. Remarkably, in PLZT the memory of several aging stages is retained also above the freezing temperature deduced from the dynamic susceptibilities. The results are discussed in light of the existing models of aging and memory in spin and dipolar glasses. PMID:15447139

2004-08-24

486

Mechanical deformation and tensile super-elastic behaviors of a Ti-Mo based shape memory alloy  

Science.gov (United States)

Ni-free shape memory alloys are promising functional materials for medical applications. A newly developed Ti-Mo based shape memory alloy shows superelasticity after thermomechanical treatment. However, the microstructure evolution and precipitation during thermomechanical processes are still not well understood. In the present paper, compressive deformation behavior at a series of temperatures of 298K - 973K and tensile deformation behavior of the alloy after aged at 573K - 973K have been investigated systematically. It is found that the compressive yield stress and ultimate compressive strength change with the deformation temperature. The ultimate tensile strength and yield stress of aged specimens also change with the aging temperature following a non-linear relationship. Microstructures of aged specimens as well as effects of lattice softening and aging-induced precipitates on ...

2011-03-01

487

Mapping subcortical diffusivity. Application to brain development. Presidential award proceeding  

International Nuclear Information System (INIS)

We studied age-related microstructural changes in the subcortical white matter from adolescence to middle age in 16 healthy male subjects (age range: 12 to 47 years) using diffusion-weighted magnetic resonance (MR) imaging (DWI). Mean diffusivity (MD) of subcortical white matter was mapped onto the overlying cortical surface using our original method. The mean MD values within 76 cortical regions were measured using atlas-based gray matter segmentation and then correlated with age. A significant negative correlation with age was observed in subcortical MD values in several cortical regions, primarily over the bilateral temporal and occipital lobes. Our results demonstrated subcortical microstructural change in postadolescence that may reflect continuing myelination. (author)

2007-01-01

488

Internet use and online social support among same sex attracted individuals of different ages  

British Library Electronic Table of Contents (United Kingdom)

The current research addressed age differences in internet use among Same Sex Attracted (SSA) individuals. In general, online communities are found to be a source of social support, especially for minority group members. However, it is unclear whether younger and older SSA people differ in their use of these communities. The present research examined age differences in use of online communities, hypothesizing that young SSA people primarily use these for social interaction and support, whereas older SSA people use online communities to seek sexual contacts. Study 1 examined age differences in motives to start using these websites. Study 2 examined age differences in use of online profiles and online social support. Results of both studies confirmed our hypotheses. Younger compared to older...

2011-01-01

489

Analysis of deteriorating processes in primary circuit facilities and determination of their priorities and relevance to the lifetime of the main primary circuit components  

International Nuclear Information System (INIS)

The major degradation mechanisms acting during the aging of selected WWER-440/213 primary circuit facilities were assessed critically. The analysis gave evidence that such mechanisms include radiation and fatigue damage of the reactor pressure vessel (effect of the neutron flow, cyclic fatigue promoted by the corrosive medium, effect of thermal aging), corrosion-mechanical and thermo-mechanical (fatigue) damage of the steam generator (stress corrosion cracking, erosion corrosion, thermal aging, wear), thermal and dynamic aging of the pressurizer, and corrosion-mechanical damage of the primary circuit piping (thermal aging, corrosion). (J.B.). 5 tabs., 1 fig., 62 refs.

490

Age and gender differences in various topographical orientation strategies  

British Library Electronic Table of Contents (United Kingdom)

Orientation in the environment can draw on a variety of cognitive strategies. We asked 634 healthy volunteers to perform a comprehensive battery administered through an internet website (www.gettinglost.ca), testing different orientation strategies in virtual environments to determine the effect of age and gender upon these skills. Older participants (46-67years of age) performed worse than younger participants (18-30 or 31-45years of age) in all orientation skills assessed, including landmark recognition, integration of body-centered information, forming association between landmarks and body turns, and the formation and use of a cognitive map. Among all tests, however, the ability to form cognitive maps resulted to be the significant factor best at predicting the individuals' age group. ...

2011-01-01

491

Influence of animal age upon antioxidant-modified UV carcinogenesis  

International Nuclear Information System (INIS)

Studies were undertaken to examine the effects of animal age on the anticarcinogenic properties of antioxidants. Female hairless mice, 2.5, 4.5 and 9.5 months of age, were subjected to daily irradiation from Westinghouse BZS-WLG lamps for 19 weeks. Experimental groups of animals were maintained on a commercial rodent meal supplemented with a 2% (w/w) antioxidant mixture. Control groups received only the meal. Tumour latency, expressed as median time to tumor development, was significantly greater for all age groups receiving antioxidants than for their similarly aged controls. However, the response to antioxidants appeared to decrease with age and the antioxidant effect was significantly less in the 9.5 month-old group than in the 2.5 month-old group. Likewise, the two youngest groups receiving antioxidants demonstrated a significantly fewer number of tumors per animal. It is ...

492

Effect of antioxidants on aging of nuclear plant cable insulation  

International Nuclear Information System (INIS)

The effects of various antioxidants and antioxidant concentrations on the radiation and thermal stability of EPDM and XLPE polymers used for insulation of electric cable in nuclear power plants were measured. The objective was to determine if particular antioxidants could be identified as being especially effective for stabilization against radiation aging and combined thermal and radiation aging. Elongation to rupture was used as the measure of stability. Materials were irradiated to doses up to 2 MGy (200 Mrad) at a dose rate of 200 to 300 Gy/h in the Cobalt-60 Gamma Irradiation Facility at the University of Virginia. All of the antioxidants tested, which were known to provide excellent thermal stability, also provided good stability for radiation aging and combined thermal/radiation aging, although small differences between antioxidants were noted. No antioxidant or antioxidant combination was ...

493

US Forces in Iraq  

Science.gov (United States)

... Army 2nd Brigade, 82nd Airborne Division Fort Bragg, NC January, 2007 ... 1st Brigade, 82nd Airborne Division Fort Bragg, NC early-2007 ...

2007-01-11

494

September 1995 Prototypes and Studies Status  

Science.gov (United States)

4) Expand to include client-server interaction (small-scale archive interactions with the goal of evaluating information management capabilities) -- Early ...

495

Remote Sensor Systems for Unmanned Planetary Missions  

Science.gov (United States)

instrument is shown in Figure 4-9 The incoming radiation is focused onto ...... An early rocket-borne ultraviolet spectrometer of the Ebert type by ...

496

Minimising the stress of weaning of beef calves: a review  

UK PubMed Central (United Kingdom)

Weaning of beef calves is usually done abruptly and early compared to the natural weaning of the species, and is associated with simultaneous exposure of calves to a range of social and environmental...Full Text Available

497

Do Perturbed Epithelial-Mesenchymal Interactions Drive Early ...  

Science.gov (United States)

... At the same time, we observed that the neoplastic properties of rat mammary gland tumor cells can be restrained and "normalized" so that they ...

2005-04-01

498

Diagnostic Value of C-reactive Protein in Complicated Appendicitis  

UK PubMed Central (United Kingdom)

PurposeEarly detection of appendicitis has increased due to development of computed tomography and ultrasonography, yet we are frequently meeting complicated appendicitis, including...Full Text Available

2011-06-01