125 research outputs found
Load Balancing and Job Migration Algorithms for Autonomic Grid Environment
Resource management and load balancing are the main areas of concern in a distributed, heterogeneous and dynamic environment like Grid. Load balancing may further cause Job migration or in some cases resubmission of Job. In this paper a number of job migration algorithms have been surveyed and studied which have resulted because of the Load balancing problem. A comparative analysis of these algorithms has also been presented which summarizes the utility and applicability of different algorithms in different environment and circumstances
An Experimental and Modeling Study on the Response to Varying Pore Pressure and Reservoir Fluids in the Morrow A Sandstone
In mature oil fields undergoing enhanced oil recovery methods, such as CO2 injection, monitoring the reservoir changes becomes important. To understand how reservoir changes influence compressional wave (P) and shear wave (S) velocities, we conducted laboratory core experiments on five core samples taken from the Morrow A sandstone at Postle Field, Oklahoma. The laboratory experiments measured P- and S-wave velocities as a function of confining pressure, pore pressure, and fluid type (which included CO2 in the gas and supercritical phase). P-wave velocity shows a response that is sensitive to both pore pressure and fluid saturation. However, S-wave velocity is primarily sensitive to changes in pore pressure. We use the fluid and pore pressure response measured from the core samples to modify velocity well logs through a log facies model correlation. The modified well logs simulate the brine- and CO2-saturated cases at minimum and maximum reservoir pressure and are inputs for full waveform seismic modeling. Modeling shows how P- and S-waves have a different time-lapse amplitude response with offset. The results from the laboratory experiments and modeling show the advantages of combining P- and S-wave attributes in recognizing the mechanism responsible for time-lapse changes due to CO2 injection
Incarcerated Grynfelt-Lesshaft's giant lumbar hernia: a case report
A uncommon posterior abdominal wall defect called the Grynfeltt-Lesshaft hernia permits the herniation of retro and intraperitoneal tissues via the upper lumbar triangle. We describe a case of a post-menopausal woman who visited the surgical OPD because of a bulge that was steadily growing in the right lumbar area. She had a history of spinal tuberculosis and underwent computed tomography (CT) guided aspiration of a paravertebral abscess and surgical fixation of vertebrae. During the initial clinical examination, the swelling resembled a large lipoma, but other potential diagnoses considered were an incisional hernia, large lipoma, abscess, or hematoma. Ultrasonography was inconclusive in differentiating due to the large size and limited visibility. Consequently, contrast-enhanced computed tomography (CECT) scans of the abdomen revealed a substantial defect in the right lumbar area with herniation of the small bowel, large bowel, and omental fat. The diagnosis of a right Grynfelt hernia was established, and the patient was referred for surgical repair. Preoperatively, the hernia was classified as a type "A" lumbar hernia, according to Moreno-Egea et al classification. For the diagnosis of lumbar hernia and surgical planning, computed tomography (CT) is the most commonly used imaging modality. It allows for accurate visualization and assessment of the hernia, aiding in both the diagnosis and the planning of the surgical procedure
A CME Source Region Catalogue and their Associated Properties
The primary objective of this study is to connect the coronal mass ejections
(CMEs) to their source regions, primarily creating a CME source region (CSR)
catalogue, and secondly probing into the influence the source regions have on
different statistical properties of CMEs. We create a source region catalogue
for 3327 CMEs from 1998 to 2017, thus capturing the different phases of cycle
23 and 24. The identified source regions are segregated into 3 classes, Active
Regions (ARs), Prominence Eruptions (PEs) and Active Prominences (APs), while
the CMEs are segregated into slow and fast based on their average projected
speeds. We find the contribution of these three source region types to the
occurrences of slow and fast CMEs to be different in the above period. A study
of the distribution of average speeds reveals different power-laws for CMEs
originating from different sources, and the power-law is different during the
different phases of cycles 23 and 24. A study of statistical latitudinal
deflections showed equator-ward deflections, while the magnitude of deflections
again bears an imprint of the source regions. An East-West asymmetry is also
noted, particularly in the rising phase of cycle 23, with the presence of
active longitudes for the CMEs, with a preference towards the Western part of
the Sun. Our results show that different aspects of CME kinematics bear a
strong imprint of the source regions they originate from, thus indicating the
existence of different ejection and/or propagation mechanisms of these CMEs.Comment: 29 Pages, 18 Figures. Accepted in The Astrophysical Journal
Supplement Series (APJS
Establishment of age-specific reference intervals for AMH in Indian women and enhancing its use as a diagnostic marker in PCOS
Background: Anti Mullerian hormone (AMH) level is a reliable marker of ovarian reserve. It is known to be influenced by factors like age, ethnicity, and ovarian pathology. Establishment of age-specific reference intervals for AMH, characteristic of different nationalities, is therefore of utmost importance. Serum AMH is known to be elevated in women with polycystic ovarian syndrome (PCOS). It is desirable to determine a population-specific cut-off of AMH, for it to be used as a diagnostic marker for PCOS.
Methods: Serum AMH, luteinizing hormone (LH), follicle-stimulating hormone (FSH), Estradiol, Progesterone and Testosterone assays were analyzed in 1978 Indian women, in the age range of 12–50 years. Age-specific reference intervals for AMH were derived for the study population. The cohort of study subjects were then divided into two groups, based on AMH values and clinical history: Control group, and patients with PCOS. The cut-off value of AMH in the study population, corresponding to the diagnosis of PCOS, was also established. Â
Results: Upper 95th percentile limits of reference intervals for the 18-25 26–30, 31–35, and 36–40, 41-45 and >45 age groups were 9.69, 7.60, 6.50, 6.1, 4.80 and 4.5 ng/ml respectively. In the PCOS group the 5th percentile value was 7.80 ng/ml and the upper 95th percentile was 21.81 ng/ml. The median percentile in PCOS group was 10.40 ng/ml. ROC analysis was done to obtain optimal cutoff values for each age group with better discriminative power than the reference limits. The best cut-off point of AMH value for PCOS in our study population was 7.51ng/ml. The sensitivity and specificity were 99.4% and 95.5%, respectively. The calculated area under the Receiver operating characteristic (ROC) curve was 0.988 (95% CI: 0.984-0.991, P <0.001). AMH, LH, and LH/FSH ratio was significantly higher in the PCOS group than in the control group (p < 0.001 for all comparisons). LH/FSH ratio was more than 2 in the PCOS group compared to controls. Serum Testosterone was significantly higher in PCOS.
Conclusions: The study aids to establish a biological reference interval for AMH, specific for different age groups in Indian women. 7.51ng/ml has been derived as a diagnostic cut-off of AMH for PCOS in our study population. The establishment of age-specific reference intervals, and syndrome-specific cut-offs in the Indian population will help overcome the influence of variables and broaden the use of AMH in women’s health
Correlation of Serum Insulin-Like Growth Factor-1 and Hand Wrist Radiographs as Skeletal Maturity Indicators: An ex-vivo Study
Introduction: Conventional Hand and Wrist radiographs, have certain drawbacks of exposing orthodontic patients to unnecessary radiation hazards and subjectivity to errors. Serum insulin-like growth factor 1 (IGF-1) levels have been reported to increase until the pubertal peak in literature. The present study aims to assess the relationship between serum IGF-1 and skeletal maturity indicators Materials and Methods: Lateral cephalograms of 60 patients were assigned SMI stage according to Fishman’s classification system. The serum IGF-1 levels of the patients were also evaluated. Correlation between the serum IGF-1 levels, age of the patient, and their SMI stage was analyzed. Results: Pearson's coefficient of correlation revealed a non-significant weak positive correlation (p=0.69; >0.05) between age and IGF-1 levels, and a non-significant weak negative correlation (p =0.52; >0.05) between SMI stages and IGF-1 levels. Results of the ANOVA test indicated that there was no significant difference between mean IGF-1 levels across the different age groups and eleven SMI groups. However, there was a significant difference noted in the mean IGF-1 levels and the restructured SMI categories and groups. Conclusion: The moderate correlation between age and serum IGF-1 fluctuations during puberty underscores the hormone's pivotal role in adolescent growth. This positions serum IGF-1 as a potentially specific and reliable marker for assessing mandibular growth modifications, offering a radiation-free alternative to conventional radiographic methods
Photoconductivity and photo-detection response of multiferroic bismuth iron oxide
We report visible light detection with in-plane BiFeO3 (BFO) thin films grown
on pre-patterned inter-digital electrodes. In-plane configured BFO film
displayed photocurrents with a 40:1 photo-to-dark-current ratio and improved
photo-sensing ability for >15000 s (4 hrs) under small bias voltage (42V).
Nearly sixty percent of the photo-induced charge carriers decay in 1.0 s and
follow a double-exponential decay model. At 373 K the effect of light does not
significantly increase the dark current, probably due to reduced mobility.
Sub-bandgap weak monochromatic light (1 mw/cm2) shows one fold increase in
photo-charge carriers.Comment: 18 pages, 7 figure
Limited Laminectomy and Restorative Spinoplasty in Spinal Canal Stenosis
Study DesignProspective cohort study.PurposeEvaluation of the clinico-radiological outcome and complications of limited laminectomy and restorative spinoplasty in spinal canal stenosis.Overview of LiteratureIt is critical to achieve adequate spinal decompression, while maintaining spinal stability.MethodsForty-four patients with degenerative lumbar canal stenosis underwent limited laminectomy and restorative spinoplasty at our centre from July 2008 to December 2010. Four patients were lost to follow-up leaving a total of 40 patients at an average final follow-up of 32 months (range, 24-41 months). There were 26 females and 14 males. The mean±standard deviation (SD) of the age was 64.7±7.6 years (range, 55-88 years). The final outcome was assessed using the Japanese Orthopaedic Association (JOA) score.ResultsAt the time of the final follow-up, all patients recorded marked improvement in their symptoms, with only 2 patients complaining of occasional mild back pain and 1 patient complaining of occasional mild leg pain. The mean±SD for the preoperative claudication distance was 95.2±62.5 m, which improved to 582±147.7 m after the operation, and the preoperative anterio-posterior canal diameter as measured on the computed tomography scan was 8.3±2.1 mm, which improved to 13.2±1.8 mm postoperatively. The JOA score improved from a mean±SD of 13.3±4.1 to 22.9±4.1 at the time of the final follow-up. As for complications, dural tears occurred in 2 patients, for which repair was performed with no additional treatment needed.ConclusionsLimited laminectomy and restorative spinoplasty is an efficient surgical procedure which relieves neurogenic claudication by achieving sufficient decompression of the cord with maintenance of spinal stability
FeFET-based MirrorBit cell for High-density NVM storage
HfO2-based Ferroelectric field-effect transistor (FeFET) has become a center
of attraction for non-volatile memory applications because of their low power,
fast switching speed, high scalability, and CMOS compatibility. In this work,
we show an n-channel FeFET-based Multibit memory, termed MirrorBit, which
effectively doubles the chip density via programming the gradient ferroelectric
polarizations in the gate using an appropriate biasing scheme. We have
experimentally demonstrated MirrorBit on GlobalFoundries HfO2-based FeFET
devices fabricated at 28 nm bulk HKMG CMOS technology. Retention of MirrorBit
states has been shown up to s at different temperatures. Also, the
endurance is found to be more than cycles. A TCAD simulation is also
presented to explain the origin and working of MirrorBit states based on the
FeFET model calibrated using the GlobalFoundries FeFET device. We have also
proposed the array-level implementation and sensing methodology of the
MirrorBit memory. Thus, we have converted 1-bit FeFET into 2-bit FeFET using a
particular programming scheme in existing FeFET, without needing any notable
fabrication process alteration, to double the chip density for high-density
non-volatile memory storage.Comment: 6 pages, 9 figure
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