Brain serotonin 4 receptor binding is inversely associated with verbal memory recall.

Science.gov (United States)

Stenbæk, Dea S; Fisher, Patrick M; Ozenne, Brice; Andersen, Emil; Hjordt, Liv V; McMahon, Brenda; Hasselbalch, Steen G; Frokjaer, Vibe G; Knudsen, Gitte M

2017-04-01

We have previously identified an inverse relationship between cerebral serotonin 4 receptor (5-HT 4 R) binding and nonaffective episodic memory in healthy individuals. Here, we investigate in a novel sample if the association is related to affective components of memory, by examining the association between cerebral 5-HT 4 R binding and affective verbal memory recall. Twenty-four healthy volunteers were scanned with the 5-HT 4 R radioligand [ 11 C]SB207145 and positron emission tomography, and were tested with the Verbal Affective Memory Test-24. The association between 5-HT 4 R binding and affective verbal memory was evaluated using a linear latent variable structural equation model. We observed a significant inverse association across all regions between 5-HT 4 R binding and affective verbal memory performances for positive ( p  = 5.5 × 10 -4 ) and neutral ( p  = .004) word recall, and an inverse but nonsignificant association for negative ( p  = .07) word recall. Differences in the associations with 5-HT 4 R binding between word categories (i.e., positive, negative, and neutral) did not reach statistical significance. Our findings replicate our previous observation of a negative association between 5-HT 4 R binding and memory performance in an independent cohort and provide novel evidence linking 5-HT 4 R binding, as a biomarker for synaptic 5-HT levels, to the mnestic processing of positive and neutral word stimuli in healthy humans.

A Projected Non-linear Conjugate Gradient Method for Interactive Inverse Kinematics

DEFF Research Database (Denmark)

Engell-Nørregård, Morten; Erleben, Kenny

2009-01-01

Inverse kinematics is the problem of posing an articulated figure to obtain a wanted goal, without regarding inertia and forces. Joint limits are modeled as bounds on individual degrees of freedom, leading to a box-constrained optimization problem. We present A projected Non-linear Conjugate...... Gradient optimization method suitable for box-constrained optimization problems for inverse kinematics. We show application on inverse kinematics positioning of a human figure. Performance is measured and compared to a traditional Jacobian Transpose method. Visual quality of the developed method...

Serum 25-Hydroxyvitamin D Concentration Is Independently Inversely Associated with Insulin Resistance in the Healthy, Non-Obese Korean Population

Directory of Open Access Journals (Sweden)

So Young Ock

2016-07-01

Full Text Available BackgroundWe evaluated the associations between 25-hydroxyvitamin D (25(OHD concentrations in serum and insulin resistance in the healthy Korean population.MethodsWe conducted this cross-sectional analysis in 1,807 healthy Korean people (628 men and 1,179 women aged 30 to 64 years in the Cardiovascular and Metabolic Disease Etiologic Research Center study. All participants were assessed for 25(OHD, fasting glucose, and insulin levels, and completed a health examination and lifestyle questionnaire according to standard procedures. Insulin resistance was defined as the homeostasis model assessment insulin resistance higher than the 75 percentile.ResultsCompared to those in the highest tertile (≥14.3 ng/mL, the odds ratio (OR for insulin resistance was 1.37 (95% confidence interval [CI], 1.01 to 1.86 for the 1st tertile (<9.7 ng/mL and 1.19 (95% CI, 0.08 to 1.62 for the 2nd tertile (9.7 to 14.3 ng/mL after adjusting for age, gender, waist circumference, alcohol consumption, smoking status, physical exercise, season, and cohort. After stratification of the subjects by adiposity, these associations remained only in non-obese subjects (lowest tertile vs. highest tertile, multivariable OR, 1.64; 95% CI, 1.05 to 2.56.ConclusionSerum 25(OHD has an independent inverse association with insulin resistance in the healthy, non-obese Korean population, even among people with vitamin D insufficiency.

Inverse scattering solution of non-linear evolution equations in one space dimension: an introduction

International Nuclear Information System (INIS)

Alvarez-Estrada, R.F.

1979-01-01

A comprehensive review of the inverse scattering solution of certain non-linear evolution equations of physical interest in one space dimension is presented. We explain in some detail the interrelated techniques which allow to linearize exactly the following equations: (1) the Korteweg and de Vries equation; (2) the non-linear Schrodinger equation; (3) the modified Korteweg and de Vries equation; (4) the Sine-Gordon equation. We concentrate in discussing the pairs of linear operators which accomplish such an exact linearization and the solution of the associated initial value problem. The application of the method to other non-linear evolution equations is reviewed very briefly

Frequency-domain full-waveform inversion with non-linear descent directions

Science.gov (United States)

Geng, Yu; Pan, Wenyong; Innanen, Kristopher A.

2018-05-01

Full-waveform inversion (FWI) is a highly non-linear inverse problem, normally solved iteratively, with each iteration involving an update constructed through linear operations on the residuals. Incorporating a flexible degree of non-linearity within each update may have important consequences for convergence rates, determination of low model wavenumbers and discrimination of parameters. We examine one approach for doing so, wherein higher order scattering terms are included within the sensitivity kernel during the construction of the descent direction, adjusting it away from that of the standard Gauss-Newton approach. These scattering terms are naturally admitted when we construct the sensitivity kernel by varying not the current but the to-be-updated model at each iteration. Linear and/or non-linear inverse scattering methodologies allow these additional sensitivity contributions to be computed from the current data residuals within any given update. We show that in the presence of pre-critical reflection data, the error in a second-order non-linear update to a background of s0 is, in our scheme, proportional to at most (Δs/s0)3 in the actual parameter jump Δs causing the reflection. In contrast, the error in a standard Gauss-Newton FWI update is proportional to (Δs/s0)2. For numerical implementation of more complex cases, we introduce a non-linear frequency-domain scheme, with an inner and an outer loop. A perturbation is determined from the data residuals within the inner loop, and a descent direction based on the resulting non-linear sensitivity kernel is computed in the outer loop. We examine the response of this non-linear FWI using acoustic single-parameter synthetics derived from the Marmousi model. The inverted results vary depending on data frequency ranges and initial models, but we conclude that the non-linear FWI has the capability to generate high-resolution model estimates in both shallow and deep regions, and to converge rapidly, relative to a

Vitamin D Levels Are Inversely Associated with Liver Fat Content and Risk of Non-Alcoholic Fatty Liver Disease in a Chinese Middle-Aged and Elderly Population: The Shanghai Changfeng Study.

Science.gov (United States)

Wang, Dan; Lin, Huandong; Xia, Mingfeng; Aleteng, Qiqige; Li, Xiaoming; Ma, Hui; Pan, Baishen; Gao, Jian; Gao, Xin

2016-01-01

Vitamin D exerts metabolic activities. We investigated whether the 25-hydroxy vitamin D [25(OH)D] is associated with liver fat content (LFC) and non-alcoholic fatty liver disease (NAFLD) in a middle-aged, elderly Chinese population. A total of 2,960 participants (954 men and 2,006 women) aged over 45 years old were enrolled. Each participant underwent a standard interview, anthropometric measurements and laboratory examinations. Vitamin D deficiency and insufficiency was diagnosed when serum 25(OH) D level was vitamin D deficiency, 769 (26.0%) had vitamin D insufficiency, and 209 (7%) had normal vitamin D. Male subjects with vitamin D deficiency and insufficiency had significantly higher LFC than those with normal 25(OH)D (P = 0.034), while the LFC values showed no significant difference among the female subjects with vitamin D sufficiency, insufficiency and deficiency (P = 0.396). Univariate correlation analysis showed that 25(OH)D had a significantly negative association with LFC in men (r = -0.085, P = 0.009), but not in women. After adjusting for age, cigarette smoking, examination season, serum calcium, PTH and all possible confounders that displayed significant associations with LFC in univariate correlation analysis, serum 25(OH)D remained associated with LFC in middle-aged and elderly Chinese men. Serum 25(OH)D level was inversely associated with LFC in middle-aged and elderly Chinese men.

On the inverse transfer of (non-)helical magnetic energy in a decaying magnetohydrodynamic turbulence

Science.gov (United States)

Park, Kiwan

2017-12-01

In our conventional understanding, large-scale magnetic fields are thought to originate from an inverse cascade in the presence of magnetic helicity, differential rotation or a magneto-rotational instability. However, as recent simulations have given strong indications that an inverse cascade (transfer) may occur even in the absence of magnetic helicity, the physical origin of this inverse cascade is still not fully understood. We here present two simulations of freely decaying helical and non-helical magnetohydrodynamic (MHD) turbulence. We verified the inverse transfer of helical and non-helical magnetic fields in both cases, but we found the underlying physical principles to be fundamentally different. In the former case, the helical magnetic component leads to an inverse cascade of magnetic energy. We derived a semi-analytic formula for the evolution of large-scale magnetic field using α coefficient and compared it with the simulation data. But in the latter case, the α effect, including other conventional dynamo theories, is not suitable to describe the inverse transfer of non-helical magnetic energy. To obtain a better understanding of the physics at work here, we introduced a 'field structure model' based on the magnetic induction equation in the presence of inhomogeneities. This model illustrates how the curl of the electromotive force leads to the build up of a large-scale magnetic field without the requirement of magnetic helicity. And we applied a quasi-normal approximation to the inverse transfer of magnetic energy.

Large Airborne Full Tensor Gradient Data Inversion Based on a Non-Monotone Gradient Method

Science.gov (United States)

Sun, Yong; Meng, Zhaohai; Li, Fengting

2018-03-01

Following the development of gravity gradiometer instrument technology, the full tensor gravity (FTG) data can be acquired on airborne and marine platforms. Large-scale geophysical data can be obtained using these methods, making such data sets a number of the "big data" category. Therefore, a fast and effective inversion method is developed to solve the large-scale FTG data inversion problem. Many algorithms are available to accelerate the FTG data inversion, such as conjugate gradient method. However, the conventional conjugate gradient method takes a long time to complete data processing. Thus, a fast and effective iterative algorithm is necessary to improve the utilization of FTG data. Generally, inversion processing is formulated by incorporating regularizing constraints, followed by the introduction of a non-monotone gradient-descent method to accelerate the convergence rate of FTG data inversion. Compared with the conventional gradient method, the steepest descent gradient algorithm, and the conjugate gradient algorithm, there are clear advantages of the non-monotone iterative gradient-descent algorithm. Simulated and field FTG data were applied to show the application value of this new fast inversion method.

Periodontitis is associated with significant hepatic fibrosis in patients with non-alcoholic fatty liver disease.

Science.gov (United States)

Alazawi, William; Bernabe, Eduardo; Tai, David; Janicki, Tomasz; Kemos, Polychronis; Samsuddin, Salma; Syn, Wing-Kin; Gillam, David; Turner, Wendy

2017-01-01

Non-alcoholic fatty liver disease (NAFLD) has a bidirectional association with metabolic syndrome. It affects up to 30% of the general population, 70% of individuals with diabetes and 90% with obesity. The main histological hallmark of progressive NAFLD is fibrosis. There is a bidirectional epidemiological link between periodontitis and metabolic syndrome. NAFLD, periodontitis and diabetes share common risk factors, are characterised by inflammation and associated with changes in commensal bacteria. Therefore we tested the hypothesis that periodontitis is associated with NAFLD and with significant fibrosis in two study groups. We analyzed data from a population-based survey and a patient-based study. NHANES III participants with abdominal ultrasound and sociodemographic, clinical, and oral examination data were extracted and appropriate weighting applied. In a separate patient-based study, consenting patients with biopsy-proved NAFLD (or with liver indices too mild to justify biopsy) underwent dental examination. Basic Periodontal Examination score was recorded. In NHANES, periodontitis was significantly associated with steatosis in 8172 adults even after adjusting for sociodemographic factors. However, associations were fully explained after accounting for features of metabolic syndrome. In the patient-based study, periodontitis was significantly more common in patients with biopsy-proven NASH and any fibrosis (F0-F4) than without NASH (p = 0.009). Periodontitis was more common in patients with NASH and significant fibrosis (F2-4) than mild or no fibrosis (F0-1, p = 0.04). Complementary evidence from an epidemiological survey and a clinical study show that NAFLD is associated with periodontitis and that the association is stronger with significant liver fibrosis.

Chromosome 17: association of a large inversion polymorphism with corticosteroid response in asthma.

Science.gov (United States)

Tantisira, Kelan G; Lazarus, Ross; Litonjua, Augusto A; Klanderman, Barbara; Weiss, Scott T

2008-08-01

A 900-kb inversion exists within a large region of conserved linkage disequilibrium (LD) on chromosome 17. CRHR1 is located within the inversion region and associated with inhaled corticosteroid response in asthma. We hypothesized that CRHR1 variants are in LD with the inversion, supporting a potential role for natural selection in the genetic response to corticosteroids. We genotyped six single nucleotide polymorphisms (SNPs) spanning chromosome 17: 40,410,565-42,372,240, including four SNPs defining inversion status. Similar allele frequencies and strong LD were noted between the inversion and a CRHR1 SNP previously associated with lung function response to inhaled corticosteroids. Each inversion-defining SNP was strongly associated with inhaled corticosteroid response in adult asthma (P values 0.002-0.005). The CRHR1 response to inhaled corticosteroids may thus be explained by natural selection resulting from inversion status or by long-range LD with another gene. Additional pharmacogenetic investigations into regions of chromosomal diversity, including copy number variation and inversions, are warranted.

An inverse method based on finite element model to derive the plastic flow properties from non-standard tensile specimens of Eurofer97 steel

Directory of Open Access Journals (Sweden)

S. Knitel

2016-12-01

Full Text Available A new inverse method was developed to derive the plastic flow properties of non-standard disk tensile specimens, which were so designed to fit irradiation rods used for spallation irradiations in SINQ (Schweizer Spallations Neutronen Quelle target at Paul Scherrer Institute. The inverse method, which makes use of MATLAB and the finite element code ABAQUS, is based upon the reconstruction of the load-displacement curve by a succession of connected small linear segments. To do so, the experimental engineering stress/strain curve is divided into an elastic and a plastic section, and the plastic section is further divided into small segments. Each segment is then used to determine an associated pair of true stress/plastic strain values, representing the constitutive behavior. The main advantage of the method is that it does not rely on a hypothetic analytical expression of the constitutive behavior. To account for the stress/strain gradients that develop in the non-standard specimen, the stress and strain were weighted over the volume of the deforming elements. The method was validated with tensile tests carried out at room temperature on non-standard flat disk tensile specimens as well as on standard cylindrical specimens made of the reduced-activation tempered martensitic steel Eurofer97. While both specimen geometries presented a significant difference in terms of deformation localization during necking, the same true stress/strain curve was deduced from the inverse method. The potential and usefulness of the inverse method is outlined for irradiated materials that suffer from a large uniform elongation reduction.

Brain serotonin 4 receptor binding is inversely associated with verbal memory recall

DEFF Research Database (Denmark)

Stenbæk, Dea S; Fisher, Patrick M; Ozenne, Brice

2017-01-01

the association between cerebral 5-HT 4R binding and affective verbal memory recall. METHODS: Twenty-four healthy volunteers were scanned with the 5-HT 4R radioligand [11C]SB207145 and positron emission tomography, and were tested with the Verbal Affective Memory Test-24. The association between 5-HT 4R binding...... and affective verbal memory was evaluated using a linear latent variable structural equation model. RESULTS: We observed a significant inverse association across all regions between 5-HT 4R binding and affective verbal memory performances for positive (p = 5.5 × 10-4) and neutral (p = .004) word recall......BACKGROUND: We have previously identified an inverse relationship between cerebral serotonin 4 receptor (5-HT 4R) binding and nonaffective episodic memory in healthy individuals. Here, we investigate in a novel sample if the association is related to affective components of memory, by examining...

Periodontitis is associated with significant hepatic fibrosis in patients with non-alcoholic fatty liver disease.

Directory of Open Access Journals (Sweden)

William Alazawi

Full Text Available Non-alcoholic fatty liver disease (NAFLD has a bidirectional association with metabolic syndrome. It affects up to 30% of the general population, 70% of individuals with diabetes and 90% with obesity. The main histological hallmark of progressive NAFLD is fibrosis. There is a bidirectional epidemiological link between periodontitis and metabolic syndrome. NAFLD, periodontitis and diabetes share common risk factors, are characterised by inflammation and associated with changes in commensal bacteria. Therefore we tested the hypothesis that periodontitis is associated with NAFLD and with significant fibrosis in two study groups.We analyzed data from a population-based survey and a patient-based study. NHANES III participants with abdominal ultrasound and sociodemographic, clinical, and oral examination data were extracted and appropriate weighting applied. In a separate patient-based study, consenting patients with biopsy-proved NAFLD (or with liver indices too mild to justify biopsy underwent dental examination. Basic Periodontal Examination score was recorded.In NHANES, periodontitis was significantly associated with steatosis in 8172 adults even after adjusting for sociodemographic factors. However, associations were fully explained after accounting for features of metabolic syndrome. In the patient-based study, periodontitis was significantly more common in patients with biopsy-proven NASH and any fibrosis (F0-F4 than without NASH (p = 0.009. Periodontitis was more common in patients with NASH and significant fibrosis (F2-4 than mild or no fibrosis (F0-1, p = 0.04.Complementary evidence from an epidemiological survey and a clinical study show that NAFLD is associated with periodontitis and that the association is stronger with significant liver fibrosis.

NON-INVASIVE INVERSE PROBLEM IN CIVIL ENGINEERING

Directory of Open Access Journals (Sweden)

Jan Havelka

2017-11-01

Full Text Available In this contribution we focus on recovery of spatial distribution of material parameters utilizing only non-invasive boundary measurements. Such methods has gained its importance as imaging techniques in medicine, geophysics or archaeology. We apply similar principles for non-stationary heat transfer in civil engineering. In oppose to standard technique which rely on external loading devices, we assume the natural fluctuation of temperature throughout day and night can provide sufficient information to recover the underlying material parameters. The inverse problem was solved by a modified regularised Gauss-Newton iterative scheme and the underlying forward problem is solved with a finite element space-time discretisation. We show a successful reconstruction of material parameters on a synthetic example with real measurements. The virtual experiment also reveals the insensitivity to practical precision of sensor measurements.

Pre- and/or Intra-Operative Prescription of Diuretics, but Not Renin-Angiotensin-System Inhibitors, Is Significantly Associated with Acute Kidney Injury after Non-Cardiac Surgery: A Retrospective Cohort Study.

Science.gov (United States)

Tagawa, Miho; Ogata, Ai; Hamano, Takayuki

2015-01-01

Pre- and/or intra-operative use of diuretics, angiotensin-converting enzyme inhibitors (ACE-I) or angiotensin II receptor blockers (ARB) constitutes a potentially modifiable risk factor for postoperative acute kidney injury (AKI). It has been studied whether use of these drugs predicts AKI after cardiac surgery. The objective of this study was to examine whether administration of these agents was independently associated with AKI after non-cardiac surgery. This was a retrospective observational study. Inclusion criteria were adult patients (age ≥ 18) who underwent non-cardiac surgery under general anesthesia from 2007 to 2009 at Kyoto Katsura Hospital. Exclusion criteria were urological surgery, missing creatinine values, and preoperative dialysis. The exposures of interest were pre- and/or intra-operative use of diuretics or ACE-I/ARB. Outcome variables were postoperative AKI as defined by the AKI Network (increase in creatinine ≥ 0.3 mg/dL or 150% within 48 hours, or urine output 6 hours). Multivariable logistic regression analyses were conducted and adjusted for potential confounders. Propensity scores (PS) for receiving diuretics or ACE-I/ARB therapy were estimated and PS adjustment, PS matching, and inverse probability weighting were performed. There were 137 AKI cases (5.0%) among 2,725 subjects. After statistical adjustment for patient and surgical characteristics, odds (95% CI) of postoperative AKI were 2.07 (1.10-3.89) (p = 0.02) and 0.89 (0.56-1.42) (p = 0.63) in users of diuretics and ACE-I/ARB, respectively, compared with non-users. PS adjustment, PS matching, and inverse probability weighting yielded similar results. The effect size of diuretics was significantly greater in the patients with lower propensity for diuretic use (p for interaction diuretics, but not ACE-I/ARB, was independently associated with postoperative AKI after non-cardiac surgery, especially in patients with low propensity for diuretic use. It might be reasonable to withhold

A dosimetric comparison between traditionally planned and inverse planned radiation therapy of non-small cell lung cancer

International Nuclear Information System (INIS)

Wu, V.W.C.; Sham, J.S.T.; Kwong, D.L.W.

2003-01-01

This study applied inverse planning in 3-dimensional conformal radiation therapy (3DCRT) of non-small cell lung cancer (NSCLC) patients and evaluated its dosimetric results by comparison with the forward planning of 3DCRT and inverse planning of intensity modulated radiotherapy (IMRT). For each of the 15 NSCLC patients recruited, the forward 3DCRT, inverse 3DCRT and inverse EVIRT plans were produced using the FOCUS treatment planning system. The dosimetric results and the planner's time of all treatment plans were recorded and compared. The inverse 3DCRT plans demonstrated the best target dose homogeneity among the three planning methods. The tumour control probability of the inverse 3DCRT plans was similar to the forward plans (p 0.217) but inferior to the IMRT plans (p < 0.001). A similar pattern was observed in uncomplicated tumour control. The average planning time for the inverse 3DCRT plans was the shortest and its difference was significant compared with the forward 3DCRT plans (p < 0.001) but not with the IMRT plans (p = 0.276). In conclusion, inverse planning for 3DCRT is a reasonable alternative to the forward planning for NSCLC patients with a reduction of the planner's time. However, further dose escalation and improvement of tumour control have to rely on IMRT. Copyright (2003) Australian Institute of Radiography

A large uterine leiomyoma leading to non-puerperal uterine inversion: A case report

Directory of Open Access Journals (Sweden)

Batool Teimoori

2017-08-01

Full Text Available Background: Although leiomyomas are the most common gynecologic disorders, non-puerperal uterine inversion due to leiomyoma is considered as a rare clinical problem. This condition can occur as a complication of a large sub-mucous leiomyoma that leads to dilate cervix and protrude into vagina. The patient may have several symptoms such as heavy vaginal bleeding, pelvic pain and intermittent acute urinary retention. Case: We presented a 32-year-old nulliparous woman with 17 years of unexplained infertility and diagnosis of a large vaginal prolapsed non-pedunculated leiomyoma. Conclusion: Haultain’s procedure was used to reposition uterine inversion and remove leiomyoma through a posterior incision, using laparotomy

Inverse Boundary Value Problem for Non-linear Hyperbolic Partial Differential Equations

OpenAIRE

Nakamura, Gen; Vashisth, Manmohan

2017-01-01

In this article we are concerned with an inverse boundary value problem for a non-linear wave equation of divergence form with space dimension $n\\geq 3$. This non-linear wave equation has a trivial solution, i.e. zero solution. By linearizing this equation at the trivial solution, we have the usual linear isotropic wave equation with the speed $\\sqrt{\\gamma(x)}$ at each point $x$ in a given spacial domain. For any small solution $u=u(t,x)$ of this non-linear equation, we have the linear isotr...

Investigation of inversion polymorphisms in the human genome using principal components analysis.

Science.gov (United States)

Ma, Jianzhong; Amos, Christopher I

2012-01-01

Despite the significant advances made over the last few years in mapping inversions with the advent of paired-end sequencing approaches, our understanding of the prevalence and spectrum of inversions in the human genome has lagged behind other types of structural variants, mainly due to the lack of a cost-efficient method applicable to large-scale samples. We propose a novel method based on principal components analysis (PCA) to characterize inversion polymorphisms using high-density SNP genotype data. Our method applies to non-recurrent inversions for which recombination between the inverted and non-inverted segments in inversion heterozygotes is suppressed due to the loss of unbalanced gametes. Inside such an inversion region, an effect similar to population substructure is thus created: two distinct "populations" of inversion homozygotes of different orientations and their 1:1 admixture, namely the inversion heterozygotes. This kind of substructure can be readily detected by performing PCA locally in the inversion regions. Using simulations, we demonstrated that the proposed method can be used to detect and genotype inversion polymorphisms using unphased genotype data. We applied our method to the phase III HapMap data and inferred the inversion genotypes of known inversion polymorphisms at 8p23.1 and 17q21.31. These inversion genotypes were validated by comparing with literature results and by checking Mendelian consistency using the family data whenever available. Based on the PCA-approach, we also performed a preliminary genome-wide scan for inversions using the HapMap data, which resulted in 2040 candidate inversions, 169 of which overlapped with previously reported inversions. Our method can be readily applied to the abundant SNP data, and is expected to play an important role in developing human genome maps of inversions and exploring associations between inversions and susceptibility of diseases.

PERMODELAN KURVA KARAKTERISTIK INVERSE NON-STANDART PADA RELE ARUS LEBIH DENGAN METODE ADAPTIVE NEURO FUZZY INFERENCE SYSTEM (ANFIS

Directory of Open Access Journals (Sweden)

Erhankana Ardiana Putra

2017-01-01

Full Text Available Pada sistem kelistrikan terutama pada sistem proteksi kelistrikan dewasa ini sangat dibutuhkan sistem yang handal, sehingga  perkembangan pada sistem proteksi sudah semakin maju dengan adanya penggunaan rele digital. Rele digital digunakan dengan mempertimbangkan kecepatan, keakuratan dan serta flexible dalam sistem koordinasi. Flexibilitas ini dimaksudkan bahwa rele digital dapat digunakan menjadi rele arus lebih (overcurrent relay sesuai pembahasan tugas akhir ini dan dapat disetting menurut keinginan user sesuai karakteristik kurva OCR konvensional/standart (normal inverse, very inverse, long time inverse, extreme inverse yang akan digunakan dalam koordinasi. Jenis kurva pada rele digital juga dapat disetting diluar rumus kurva konvensional/standart yang seperti sudah disebutkan sebelumnya, kurva diluar rumusan standart disebut kurva rele non-standart. Kurva rele non-standart digunakan untuk memudahkan pengguna untuk menentukan waktu trip berdasarkan arus yang diinginkan dan sebagai solusi jika pada koordinasi proteksi mengalami kendala dalam koordinasi kurva rele. Pada tugas akhir ini akan dibahas bagaimana membuat atau memodelkan kurva karakteristik inverse overcurrent rele non-standart dengan menggunakan metode (Adaptive Neuro Fuzzy Inference System atau biasa disebut metode pembelajaran ANFIS. Kurva non-standart didapatkan dengan pengambilan titik-titik data baru berupa arus dan waktu trip sesuai keinginan user. Data baru tersebut akan digabungkan dengan data lama sehingga menghasilkan data non-standart yang nantinya akan dilakukan pembelajaran dengan metode ANFIS untuk mendapatkan desain kurva non-standart. Setelah didapatkan desain kurva non-standart akan dilakukan pengujian keakuratan dengan mengganti nilai MF (membership function didapatkan hasil rata-rata error terkecil 2,56% (MF=10 dan epoch=100. Pengujian selanjutnya dengan mengubah nilai epoch didapatkan nilai keakuratan dengan error terkecil pada epoch = 500. Simulasi pada

Medial joint line bone bruising at MRI complicating acute ankle inversion injury: What is its clinical significance?

International Nuclear Information System (INIS)

Chan, V.O.; Moran, D.E.; Shine, S.; Eustace, S.J.

2013-01-01

Aim: To assess the incidence and clinical significance of medial joint line bone bruising following acute ankle inversion injury. Materials and methods: Forty-five patients who underwent ankle magnetic resonance imaging (MRI) within 2 weeks of acute ankle inversion injury were included in this prospective study. Integrity of the lateral collateral ligament complex, presence of medial joint line bone bruising, tibio-talar joint effusion, and soft-tissue swelling were documented. Clinical follow-up at 6 months was carried out to determine the impact of injury on length of time out of work, delay in return to normal walking, delay in return to sports activity, and persistence of medial joint line pain. Results: Thirty-seven patients had tears of the anterior talofibular ligament (ATFL). Twenty-six patients had medial joint line bone bruising with altered marrow signal at the medial aspect of the talus and congruent surface of the medial malleolus. A complete ATFL tear was seen in 92% of the patients with medial joint line bone bruising (p = 0.05). Patients with an ATFL tear and medial joint line bone bruising had a longer delay in return to normal walking (p = 0.0002), longer delay in return to sports activity (p = 0.0001), and persistent medial joint line pain (p = 0.0003). There was no statistically significant difference in outcome for the eight patients without ATFL tears. Conclusion: Medial joint line bone bruising following an acute ankle inversion injury was significantly associated with a complete ATFL tear, longer delay in the return to normal walking and sports activity, as well as persistent medial joint line pain. Its presence should prompt detailed assessment of the lateral collateral ligament complex, particularly the ATFL

Non-unitary neutrino mixing and CP violation in the minimal inverse seesaw model

International Nuclear Information System (INIS)

Malinsky, Michal; Ohlsson, Tommy; Xing, Zhi-zhong; Zhang He

2009-01-01

We propose a simplified version of the inverse seesaw model, in which only two pairs of the gauge-singlet neutrinos are introduced, to interpret the observed neutrino mass hierarchy and lepton flavor mixing at or below the TeV scale. This 'minimal' inverse seesaw scenario (MISS) is technically natural and experimentally testable. In particular, we show that the effective parameters describing the non-unitary neutrino mixing matrix are strongly correlated in the MISS, and thus, their upper bounds can be constrained by current experimental data in a more restrictive way. The Jarlskog invariants of non-unitary CP violation are calculated, and the discovery potential of such new CP-violating effects in the near detector of a neutrino factory is discussed.

Chocolate Consumption is Inversely Associated with Calcified Atherosclerotic Plaque in the Coronary Arteries: The NHLBI Family Heart Study

Science.gov (United States)

Djoussé, Luc; Hopkins, Paul N.; Arnett, Donna K.; Pankow, James S.; Borecki, Ingrid; North, Kari E.; Ellison, R. Curtis

2010-01-01

Background and Aims While a diet rich in anti-oxidant has been favorably associated with coronary disease and hypertension, limited data have evaluated the influence of such diet on subclinical disease. Thus, we sought to examine whether chocolate consumption is associated with calcified atherosclerotic plaque in the coronary arteries (CAC). Methods In a cross-sectional design, we studied 2,217 participants of the NHLBI Family Heart Study. Chocolate consumption was assessed by a semi-quantitative food-frequency questionnaire and CAC was measured by cardiac CT. We defined prevalent CAC using an Agatston score of at least 100 and fitted generalized estimating equations to calculate prevalence odds ratios of CAC. Results There was an inverse association between frequency of chocolate consumption and prevalent CAC. Odds ratios (95% CI) for CAC were 1.0 (reference), 0.94 (0.66-1.35), 0.78 (0.53-1.13), and 0.68 (0.48-0.97) for chocolate consumption of 0, 1-3 times per month, once per week, and 2+ times per week, respectively (p for trend 0.022), adjusting for age, sex, energy intake, waist-hip ratio, education, smoking, alcohol consumption, ratio of total-to-HDL-cholesterol, non-chocolate candy, and diabetes mellitus. Controlling for additional confounders did not alter the findings. Exclusion of subjects with coronary heart disease or diabetes mellitus did not materially change the odds ratio estimates but did modestly decrease the overall significance (p = 0.07). Conclusions These data suggest that chocolate consumption might be inversely associated with prevalent CAC. PMID:20655129

On dynamically consistent Jacobian inverse for non-holonomic robotic systems

Directory of Open Access Journals (Sweden)

Ratajczak Joanna

2017-12-01

Full Text Available This paper presents the dynamically consistent Jacobian inverse for non-holonomic robotic system, and its application to solving the motion planning problem. The system’s kinematics are represented by a driftless control system, and defined in terms of its input-output map in accordance with the endogenous configuration space approach. The dynamically consistent Jacobian inverse (DCJI has been introduced by means of a Riemannian metric in the endogenous configuration space, exploiting the reduced inertia matrix of the system’s dynamics. The consistency condition is formulated as the commutativity property of a diagram of maps. Singular configurations of DCJI are studied, and shown to coincide with the kinematic singularities. A parametric form of DCJI is derived, and used for solving example motion planning problems for the trident snake mobile robot. Some advantages in performance of DCJI in comparison to the Jacobian pseudoinverse are discovered.

Dietary Phytoestrogen Intake is Inversely Associated with Hypertension in a Cohort of Adults Living in the Mediterranean Area

Directory of Open Access Journals (Sweden)

Justyna Godos

2018-02-01

Full Text Available Background: Dietary polyphenols, including phytoestrogens are abundantly present in a balanced diet. Evidence for their role in preventing non-communicable diseases is emerging. Methods: We examined the association between estimated habitual intakes of dietary phytoestrogens and hypertension in a cohort study. The baseline data included 1936 men and women aged 18 years and older. Intakes of total phytoestrogens, isoflavones, and lignans were calculated from validated food frequency questionnaire. Data on the polyphenols content in foods were retrieved from the Phenol-Explorer database. Results: Individuals in the highest quartile of dietary phytoestrogens intake were less likely to be hypertensive (OR: 0.66, 95% CI: 0.44–0.98; moreover, the association showed a significant decreasing trend. Isoflavones and lignans were not associated with lower odds of hypertension; however, some individual compounds, such as biochanin A and pinoresinol showed an independent inverse association with hypertension. Conclusions: Dietary phytoestrogens are associated with lower likelihood of hypertension in adults living in the Mediterranean area. Future studies are needed to confirm the present findings (i.e., prospective cohort studies and to better understand the mechanisms underlying such associations.

Incremental inverse kinematics based vision servo for autonomous robotic capture of non-cooperative space debris

Science.gov (United States)

Dong, Gangqi; Zhu, Z. H.

2016-04-01

This paper proposed a new incremental inverse kinematics based vision servo approach for robotic manipulators to capture a non-cooperative target autonomously. The target's pose and motion are estimated by a vision system using integrated photogrammetry and EKF algorithm. Based on the estimated pose and motion of the target, the instantaneous desired position of the end-effector is predicted by inverse kinematics and the robotic manipulator is moved incrementally from its current configuration subject to the joint speed limits. This approach effectively eliminates the multiple solutions in the inverse kinematics and increases the robustness of the control algorithm. The proposed approach is validated by a hardware-in-the-loop simulation, where the pose and motion of the non-cooperative target is estimated by a real vision system. The simulation results demonstrate the effectiveness and robustness of the proposed estimation approach for the target and the incremental control strategy for the robotic manipulator.

Symmetry realization via a dynamical inverse Higgs mechanism

Science.gov (United States)

Rothstein, Ira Z.; Shrivastava, Prashant

2018-05-01

The Ward identities associated with spontaneously broken symmetries can be saturated by Goldstone bosons. However, when space-time symmetries are broken, the number of Goldstone bosons necessary to non-linearly realize the symmetry can be less than the number of broken generators. The loss of Goldstones may be due to a redundancy or the generation of a gap. In either case the associated Goldstone may be removed from the spectrum. This phenomena is called an Inverse Higgs Mechanism (IHM) and its appearance has a well defined mathematical condition. However, there are cases when a Goldstone boson associated with a broken generator does not appear in the low energy theory despite the lack of the existence of an associated IHM. In this paper we will show that in such cases the relevant broken symmetry can be realized, without the aid of an associated Goldstone, if there exists a proper set of operator constraints, which we call a Dynamical Inverse Higgs Mechanism (DIHM). We consider the spontaneous breaking of boosts, rotations and conformal transformations in the context of Fermi liquids, finding three possible paths to symmetry realization: pure Goldstones, no Goldstones and DIHM, or some mixture thereof. We show that in the two dimensional degenerate electron system the DIHM route is the only consistent way to realize spontaneously broken boosts and dilatations, while in three dimensions these symmetries could just as well be realized via the inclusion of non-derivatively coupled Goldstone bosons. We present the action, including the leading order non-linearities, for the rotational Goldstone (angulon), and discuss the constraint associated with the possible DIHM that would need to be imposed to remove it from the spectrum. Finally we discuss the conditions under which Goldstone bosons are non-derivatively coupled, a necessary condition for the existence of a Dynamical Inverse Higgs Constraint (DIHC), generalizing the results for Vishwanath and Wantanabe.

Prognosis of non-significant coronary atherosclerotic disease detected by coronary artery tomography

Energy Technology Data Exchange (ETDEWEB)

Barros, Marcio Vinicius Lins; Siqueira, Bruna Pinto; Guimaraes, Carolina Camargos Braichi; Cruz, David Filipe Silva; Guimaraes, Leiziane Assuncao Alves; Lima, Maicom Marcio Perigolo, E-mail: marciovlbarros@gmail.com [Faculdade de Saude e Ecologia Humana, Vespasiano, MG (Brazil); Nunes, Maria do Carmo Pereira [Universidade de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Faculdade de Medicina; Siqueira, Maria Helena Albernaz [Hospital Materdei, Belo Horizonte, MG (Brazil)

2015-07-15

Introduction: Although studies have shown high diagnostic accuracy of coronary tomography (CT) in detecting coronary artery disease (CAD), data on the prognostic value of this method in patients with no significant coronary obstruction are limited. Objective: To evaluate the value of CT in predicting adverse events in patients with suspected CAD and no significant coronary obstruction. Methods: We prospectively evaluated 440 patients between January 2008 and July 2013 by MDCT, diagnosed with no significant obstruction or no atherosclerotic coronary obstruction with an average follow-up of 33 months. The outcomes evaluated were: cardiac death, myocardial infarction, unstable angina associated with hospitalization or coronary artery bypass grafting. Results: Of the 440 patients studied, 295 (67%) were men with mean age 55.9 ± 12.0 years. Non-significant obstruction was found in 152 (35%) of the patients and there were 49 (11%) outcomes. In the multivariate analysis using the Cox regression model, the predictors of clinical outcomes were non-significant obstruction on CT (hazard ratio 3.51; 95% CI 1.73 - 7.8; p <0.01), age and hypertension. Non-significant obstruction on CT was associated with adverse clinical outcomes and survival analysis showed a significant difference (log-rank 24.6; p <0.01) in predicting these outcomes. Conclusion: The detection of non-significant atherosclerotic obstruction by CT was associated with the presence of adverse events in patients with suspected CAD, which may prove useful in the risk stratification of these patients. (author)

An inverse association between tea consumption and colorectal cancer risk.

Science.gov (United States)

Chen, Yuetong; Wu, Yuan; Du, Mulong; Chu, Haiyan; Zhu, Lingjun; Tong, Na; Zhang, Zhengdong; Wang, Meilin; Gu, Dongying; Chen, Jinfei

2017-06-06

It is well known that the tea extracts, mainly polyphenols as chemo-preventive elements, could act as cancer progression blockers. Although the association between tea consumption and colorectal cancer risk has been widely investigated, the results still remain inconsistent. We conducted a dose-response meta-analysis to evaluate their relationships by enrolling qualified 29 literatures. The summary odds ratio (OR) of colorectal cancer for the highest vs. lowest tea consumption was 0.93 with 0.87-1.00 of 95% confidence intervals (CIs) among all studies with modest heterogeneity (P = 0.001, I2 = 43.4%). Stratified analysis revealed that tea, especially green tea, had a protective effect among female and rectal cancer patients. Particularly, the dose-response analysis showed that there was a significant inverse association between an increment of 1 cup/day of tea consumption and colorectal cancer risk in the subgroup of the green tea drinking (OR = 0.98, 95% CI = 0.96-1.01, Pnonlinear = 0.003) and female (OR = 0.68, 95% CI = 0.56-0.81, Pnonlinear colorectal cancer risk, which may have significant public health implications in the prevention of colorectal cancer and further similar researches.

Remarks on the inverse scattering transform associated with toda equations

Science.gov (United States)

Ablowitz, Mark J.; Villorroel, J.

The Inverse Scattering Transforms used to solve both the 2+1 Toda equation and a novel reduction, the Toda differential-delay equations are outlined. There are a number of interesting features associated with these systems and the related scattering theory.

Serum Folate Shows an Inverse Association with Blood Pressure in a Cohort of Chinese Women of Childbearing Age: A Cross-Sectional Study.

Directory of Open Access Journals (Sweden)

Minxue Shen

Full Text Available It has been reported that higher folate intake from food and supplementation is associated with decreased blood pressure (BP. The association between serum folate concentration and BP has been examined in few studies. We aim to examine the association between serum folate and BP levels in a cohort of young Chinese women.We used the baseline data from a pre-conception cohort of women of childbearing age in Liuyang, China, for this study. Demographic data were collected by structured interview. Serum folate concentration was measured by immunoassay, and homocysteine, blood glucose, triglyceride and total cholesterol were measured through standardized clinical procedures. Multiple linear regression and principal component regression model were applied in the analysis.A total of 1,532 healthy normotensive non-pregnant women were included in the final analysis. The mean concentration of serum folate was 7.5 ± 5.4 nmol/L and 55% of the women presented with folate deficiency (< 6.8 nmol/L. Multiple linear regression and principal component regression showed that serum folate levels were inversely associated with systolic and diastolic BP, after adjusting for demographic, anthropometric, and biochemical factors.Serum folate is inversely associated with BP in non-pregnant women of childbearing age with high prevalence of folate deficiency.

The association between the metabolic syndrome and metabolic syndrome score and pulmonary function in non-smoking adults.

Science.gov (United States)

Yoon, Hyun; Gi, Mi Young; Cha, Ju Ae; Yoo, Chan Uk; Park, Sang Muk

2018-03-01

This study assessed the association of metabolic syndrome and metabolic syndrome score with the predicted forced vital capacity and predicted forced expiratory volume in 1 s (predicted forced expiratory volume in 1 s) values in Korean non-smoking adults. We analysed data obtained from 6684 adults during the 2013-2015 Korean National Health and Nutrition Examination Survey. After adjustment for related variables, metabolic syndrome ( p metabolic syndrome score ( p metabolic syndrome score with metabolic syndrome score 0 as a reference group showed no significance for metabolic syndrome score 1 [1.061 (95% confidence interval, 0.755-1.490)] and metabolic syndrome score 2 [1.247 (95% confidence interval, 0.890-1.747)], but showed significant for metabolic syndrome score 3 [1.433 (95% confidence interval, 1.010-2.033)] and metabolic syndrome score ⩾ 4 [1.760 (95% confidence interval, 1.216-2.550)]. In addition, the odds ratio of restrictive pulmonary disease of the metabolic syndrome [1.360 (95% confidence interval, 1.118-1.655)] was significantly higher than those of non-metabolic syndrome. Metabolic syndrome and metabolic syndrome score were inversely associated with the predicted forced vital capacity and forced expiratory volume in 1 s values in Korean non-smoking adults. In addition, metabolic syndrome and metabolic syndrome score were positively associated with the restrictive pulmonary disease.

Efficient Monte Carlo sampling of inverse problems using a neural network-based forward—applied to GPR crosshole traveltime inversion

Science.gov (United States)

Hansen, T. M.; Cordua, K. S.

2017-12-01

Probabilistically formulated inverse problems can be solved using Monte Carlo-based sampling methods. In principle, both advanced prior information, based on for example, complex geostatistical models and non-linear forward models can be considered using such methods. However, Monte Carlo methods may be associated with huge computational costs that, in practice, limit their application. This is not least due to the computational requirements related to solving the forward problem, where the physical forward response of some earth model has to be evaluated. Here, it is suggested to replace a numerical complex evaluation of the forward problem, with a trained neural network that can be evaluated very fast. This will introduce a modeling error that is quantified probabilistically such that it can be accounted for during inversion. This allows a very fast and efficient Monte Carlo sampling of the solution to an inverse problem. We demonstrate the methodology for first arrival traveltime inversion of crosshole ground penetrating radar data. An accurate forward model, based on 2-D full-waveform modeling followed by automatic traveltime picking, is replaced by a fast neural network. This provides a sampling algorithm three orders of magnitude faster than using the accurate and computationally expensive forward model, and also considerably faster and more accurate (i.e. with better resolution), than commonly used approximate forward models. The methodology has the potential to dramatically change the complexity of non-linear and non-Gaussian inverse problems that have to be solved using Monte Carlo sampling techniques.

Evaluation of the significance of inverse oxidation for HTGR graphites

International Nuclear Information System (INIS)

Lee, B.S.; Heiser, J. III; Sastre, C.

1983-01-01

The inverse oxidation refers to a higher mass loss inside the graphite than the outside. In 1980, Wichner et al reported this phenomenon (referred to as inside/out corrosion) observed in some H451 graphites, and offered an explanation that a catalyst (almost certainly Fe) is activated by the progressively increasing reducing conditions found in the graphite interior. Recently, Morgan and Thomas (1982) investigated this phenomenon is PGX graphites, and agreed on the existing mechanism to explain this pheomenon. They also called for attention to the possibility that this phenomenon may occur under HTGR (High Temperature Gas-Cooled Reactor) operating conditions. The purpose of this paper is to confirm the above mentioned explanation for this phenomenon and to evaluate the significance of this effect for HTGR graphites under realistic reactor conditions

Visceral adiposity index is associated with significant fibrosis in patients with non-alcoholic fatty liver disease.

Science.gov (United States)

Petta, S; Amato, M C; Di Marco, V; Cammà, C; Pizzolanti, G; Barcellona, M R; Cabibi, D; Galluzzo, A; Sinagra, D; Giordano, C; Craxì, A

2012-01-01

Metabolic factors have been associated with liver damage in patients with non-alcoholic fatty liver disease (NAFLD). To test a new marker of adipose dysfunction, the visceral adiposity index (VAI), in NAFLD patients to assess whether or not it is associated with host factors, and to investigate a potential correlation with histological findings. One hundred and forty-two consecutive NAFLD patients were evaluated by liver biopsy, and clinical and metabolic measurements, including insulin resistance with the homeostasis model assessment (HOMA), and VAI by using waist circumference, body mass index, triglycerides and HDL. Serum levels of TNFα, IL-6, adiponectin and leptin were also assessed. All biopsies were scored for NAFLD activity score (NAS) and its components, and for staging (Kleiner). By multiple linear regression analysis, VAI was independently associated with higher HOMA (P = 0.04), and fibrosis (P = 0.04). In addition, an independent association was found between higher VAI and lower adiponectin levels (P = 0.002). Higher HOMA (OR 1.149, 95% CI 1.003-1.316, P = 0.04), higher VAI (OR 1.446, 95% CI 1.023-2.043, P = 0.03), lobular inflammation (OR 3.777, 95% CI 1.771-8.051, P = 0.001), and ballooning (OR 2.884, 95% CI 1.231-6.757, P = 0.01) were correlated with significant fibrosis (F2-F4) on multiple logistic regression analysis. In particular, the prevalence of significant fibrosis progressively increased from patients with a VAI ≤ 2.1 and HOMA ≤ 3.4 (26%) to those with a VAI > 2.1 and HOMA > 3.4 (83%). In NAFLD patients, visceral adiposity index is an expression of both qualitative and quantitative adipose tissue dysfunction and, together with insulin resistance, is independently correlated with significant fibrosis. © 2011 Blackwell Publishing Ltd.

Inverse reasoning processes in obsessive-compulsive disorder.

Science.gov (United States)

Wong, Shiu F; Grisham, Jessica R

2017-04-01

The inference-based approach (IBA) is one cognitive model that aims to explain the aetiology and maintenance of obsessive-compulsive disorder (OCD). The model proposes that certain reasoning processes lead an individual with OCD to confuse an imagined possibility with an actual probability, a state termed inferential confusion. One such reasoning process is inverse reasoning, in which hypothetical causes form the basis of conclusions about reality. Although previous research has found associations between a self-report measure of inferential confusion and OCD symptoms, evidence of a specific association between inverse reasoning and OCD symptoms is lacking. In the present study, we developed a task-based measure of inverse reasoning in order to investigate whether performance on this task is associated with OCD symptoms in an online sample. The results provide some evidence for the IBA assertion: greater endorsement of inverse reasoning was significantly associated with OCD symptoms, even when controlling for general distress and OCD-related beliefs. Future research is needed to replicate this result in a clinical sample and to investigate a potential causal role for inverse reasoning in OCD. Copyright © 2016 Elsevier Ltd. All rights reserved.

The development of computational algorithms for manipulator inverse kinematics

International Nuclear Information System (INIS)

Sasaki, Shinobu

1989-10-01

A solution technique of the inverse kinematics for multi-joint robot manipulators has been considered to be one of the most cumbersome treatment due to non-linearity properties inclusive of trigonometric functions. The most traditional approach is to use the Jacobian matrix on linearization assumptions. This iterative technique, however, is attended with numerical problems having significant influences on the solution characteristics such as initial guess dependence and singularities. Taking these facts into consideration, new approaches have been proposed from different standpoints, which are based on polynomial transformation of kinematic model, the minimization technique in mathematical programming, vector-geometrical concept, and the separation of joint variables associated with the optimization problem. In terms of computer simulations, each approach was identified to be a useful algorithm which leads to theoretically accurate solutions to complicated inverse problems. In this way, the short-term goal of our studies on manipulator inverse problem in the R and D project of remote handling technology was accomplished with success, and consequently the present report sums up the results of basic studies on this matter. (author)

Inverse association between serum creatinine and mortality in acute kidney injury.

Science.gov (United States)

de Souza, Sergio Pinto; Matos, Rodrigo Santos; Barros, Luisa Leite; Rocha, Paulo Novis

2014-01-01

Sepsis is a leading precipitant of Acute Kidney Injury (AKI) in intensive care unit (ICU) patients, and is associated with a high mortality rate. We aimed to evaluate the risk factors for dialysis and mortality in a cohort of AKI patients of predominantly septic etiology. Adult patients from an ICU for whom nephrology consultation was requested were included. End-stage chronic renal failure and kidney transplant patients were excluded. 114 patients were followed. Most had sepsis (84%), AKIN stage 3 (69%) and oliguria (62%) at first consultation. Dialysis was performed in 66% and overall mortality was 70%. Median serum creatinine in survivors and non-survivors was 3.95 mg/dl (2.63 - 5.28) and 2.75 mg/dl (1.81 - 3.69), respectively. In the multivariable models, oliguria and serum urea were positively associated with dialysis; otherwise, a lower serum creatinine at first consultation was independently associated with higher mortality. In a cohort of septic AKI, oliguria and serum urea were the main indications for dialysis. We also described an inverse association between serum creatinine and mortality. Potential explanations for this finding include: delay in diagnosis, fluid overload with hemodilution of serum creatinine or poor nutritional status. This finding may also help to explain the low discriminative power of general severity scores - that assign higher risks to higher creatinine levels - in septic AKI patients.

Association between Dietary Vitamin C Intake and Non-Alcoholic Fatty Liver Disease: A Cross-Sectional Study among Middle-Aged and Older Adults.

Science.gov (United States)

Wei, Jie; Lei, Guang-Hua; Fu, Lei; Zeng, Chao; Yang, Tuo; Peng, Shi-Fang

2016-01-01

Non-alcoholic fatty liver disease (NAFLD) has become one of the most prevalent chronic liver disease all over the world. The objective of this study was to evaluate the association between dietary vitamin C intake and NAFLD. Subjects were diagnosed with NAFLD by abdominal ultrasound examination and the consumption of alcohol was less than 40g/day for men or less than 20g/day for women. Vitamin C intake was classified into four categories according to the quartile distribution in the study population: ≤74.80 mg/day, 74.81-110.15 mg/day, 110.16-146.06 mg/day, and ≥146.07 mg/day. The energy and multi-variable adjusted odds ratio (OR), as well as their corresponding 95% confidence interval (CI), were used to determine the relationship between dietary vitamin C intake and NAFLD through logistic regression. The present cross-sectional study included 3471 subjects. A significant inverse association between dietary vitamin C intake and NAFLD was observed in the energy-adjusted and the multivariable model. The multivariable adjusted ORs (95%CI) for NAFLD were 0.69 (95%CI: 0.54-0.89), 0.93 (95%CI: 0.72-1.20), and 0.71 (95%CI: 0.53-0.95) in the second, third and fourth dietary vitamin C intake quartiles, respectively, compared with the lowest (first) quartile. The relative odds of NAFLD was decreased by 0.71 times in the fourth quartile of dietary vitamin C intake compared with the lowest quartile. After stratifying data by sex or the status of obesity, the inverse association remained valid in the male population or non-obesity population, but not in the female population or obesity population. There might be a moderate inverse association between dietary vitamin C intake and NAFLD in middle-aged and older adults, especially for the male population and non-obesity population.

Association between Dietary Vitamin C Intake and Non-Alcoholic Fatty Liver Disease: A Cross-Sectional Study among Middle-Aged and Older Adults.

Directory of Open Access Journals (Sweden)

Jie Wei

Full Text Available Non-alcoholic fatty liver disease (NAFLD has become one of the most prevalent chronic liver disease all over the world. The objective of this study was to evaluate the association between dietary vitamin C intake and NAFLD.Subjects were diagnosed with NAFLD by abdominal ultrasound examination and the consumption of alcohol was less than 40g/day for men or less than 20g/day for women. Vitamin C intake was classified into four categories according to the quartile distribution in the study population: ≤74.80 mg/day, 74.81-110.15 mg/day, 110.16-146.06 mg/day, and ≥146.07 mg/day. The energy and multi-variable adjusted odds ratio (OR, as well as their corresponding 95% confidence interval (CI, were used to determine the relationship between dietary vitamin C intake and NAFLD through logistic regression.The present cross-sectional study included 3471 subjects. A significant inverse association between dietary vitamin C intake and NAFLD was observed in the energy-adjusted and the multivariable model. The multivariable adjusted ORs (95%CI for NAFLD were 0.69 (95%CI: 0.54-0.89, 0.93 (95%CI: 0.72-1.20, and 0.71 (95%CI: 0.53-0.95 in the second, third and fourth dietary vitamin C intake quartiles, respectively, compared with the lowest (first quartile. The relative odds of NAFLD was decreased by 0.71 times in the fourth quartile of dietary vitamin C intake compared with the lowest quartile. After stratifying data by sex or the status of obesity, the inverse association remained valid in the male population or non-obesity population, but not in the female population or obesity population.There might be a moderate inverse association between dietary vitamin C intake and NAFLD in middle-aged and older adults, especially for the male population and non-obesity population.

Solution of the inverse scattering problem at fixed energy with non-physical S matrix elements

International Nuclear Information System (INIS)

Eberspaecher, M.; Amos, K.; Apagyi, B.

1999-12-01

The quantum mechanical inverse elastic scattering problem is solved with the modified Newton-Sabatier method. A set of S matrix elements calculated from a realistic analytic optical model potential serves as input data. It is demonstrated that the quality of the inversion potential can be improved by including non-physical S matrix elements to half, quarter and eighth valued partial waves if the original set does not contain enough information to determine the interaction potential. We demonstrate that results can be very sensitive to the choice of those non-physical S matrix values both with the analytic potential model and in a real application in which the experimental cross section for the symmetrical scattering system of 12 C+ 12 C at E=7.998 MeV is analyzed

Inverse problems with non-trivial priors: efficient solution through sequential Gibbs sampling

DEFF Research Database (Denmark)

Hansen, Thomas Mejer; Cordua, Knud Skou; Mosegaard, Klaus

2012-01-01

Markov chain Monte Carlo methods such as the Gibbs sampler and the Metropolis algorithm can be used to sample solutions to non-linear inverse problems. In principle, these methods allow incorporation of prior information of arbitrary complexity. If an analytical closed form description of the prior...... is available, which is the case when the prior can be described by a multidimensional Gaussian distribution, such prior information can easily be considered. In reality, prior information is often more complex than can be described by the Gaussian model, and no closed form expression of the prior can be given....... We propose an algorithm, called sequential Gibbs sampling, allowing the Metropolis algorithm to efficiently incorporate complex priors into the solution of an inverse problem, also for the case where no closed form description of the prior exists. First, we lay out the theoretical background...

Hyperuricemia Inversely Correlates with Disease Severity in Taiwanese Nonalcoholic Steatohepatitis Patients.

Directory of Open Access Journals (Sweden)

Jee-Fu Huang

Full Text Available Asians are more susceptible to non-alcoholic steatohepatitis (NASH as well as metabolic disorder than other ethnicities. We aimed to assess the interaction between metabolic factors and fibrosis in Taiwanese NASH patients.A total of 130 biopsy-proven Taiwanese NASH patients (94 males, age = 43.0 ± 13.0 years were consecutively enrolled. Their demographic, metabolic profiles and histopathological manifestations were analyzed.Twenty-four (18.5% NASH patients were non-obese. Thirty-three (25.4% patients had significant fibrosis (F2 or more: 22 (16.9% patients were of F2, whilst 11 (8.5% patients were of advanced fibrosis (F3-4. The prevalence of metabolic syndrome, diabetes and hypertension were 60.8%, 39.4%, and 61.5%, respectively. There was a significant inverse correlation between hyperuricemia and fibrosis stages, ranging from 48.4% of F0-1, 33.3% of F2, and 9.1% of F3-4, respectively (P = 0.01, linear trend. Multivariate logistic regression analysis showed that a decreased serum albumin level (OR = 40.0, 95% CI = 4.5-300, P = 0.001 and normal uric acid level (OR = 5.6, 95% CI = 1.5-21.7, P = 0.01 were the significant factors associated with significant fibrosis.Hyperuricemia inversely predicts fibrosis stages. Females might carry a more disease severity than males in Taiwanese NASH patients.

Coffee and Tea Consumption Are Inversely Associated with Mortality in a Multiethnic Urban Population123

Science.gov (United States)

Gardener, Hannah; Rundek, Tatjana; Wright, Clinton B.; Elkind, Mitchell S. V.; Sacco, Ralph L.

2013-01-01

Coffee and tea are commonly consumed beverages. Inverse associations with mortality have been suggested for coffee and tea, but the relationships with cause-specific mortality are not well understood. We examined regular and decaffeinated coffee and tea in relation to mortality due to all causes, vascular, nonvascular, and cancer in the multi-ethnic, prospective, population-based Northern Manhattan Study. The study population included 2461 participants with diet data who were free of stroke, myocardial infarction, and cancer at baseline (mean age 68.30 ± 10.23 y, 36% men, 19% white, 23% black, 56% Hispanic). During a mean follow-up of 11 y, we examined the associations between coffee and tea consumption, assessed by food frequency questionnaire, and 863 deaths (342 vascular related and 444 nonvascular including 160 cancer deaths) using multivariable-adjusted Cox models. Coffee consumption was inversely associated with all-cause mortality [for each additional cup/d, HR = 0.93 (95% CI: 0.88, 0.99); P = 0.02]. Caffeinated coffee was inversely associated with all-cause mortality, driven by a strong protection among those who drank ≥4 cups/d. An inverse dose-response relationship between tea and all-cause mortality was suggested [for each additional cup/d, HR = 0.91 (95% CI: 0.84, 0.99); P = 0.01]. Coffee consumption ≥4/d was protective against nonvascular death [vs. coffee and vascular-related mortality among Hispanics only. Further study is needed, including investigation into the mechanisms and compounds in coffee and tea responsible for the inverse associations with mortality. The differential relationship between coffee and vascular death across race/ethnicity underscores the need for research in similar multi-ethnic cohorts including Hispanics. PMID:23784068

Inverse association between serum creatinine and mortality in acute kidney injury

Directory of Open Access Journals (Sweden)

Sergio Pinto de Souza

2014-12-01

Full Text Available Introduction: Sepsis is a leading precipitant of Acute Kidney Injury (AKI in intensive care unit (ICU patients, and is associated with a high mortality rate. Objective: We aimed to evaluate the risk factors for dialysis and mortality in a cohort of AKI patients of predominantly septic etiology. Methods: Adult patients from an ICU for whom nephrology consultation was requested were included. End-stage chronic renal failure and kidney transplant patients were excluded. Results: 114 patients were followed. Most had sepsis (84%, AKIN stage 3 (69% and oliguria (62% at first consultation. Dialysis was performed in 66% and overall mortality was 70%. Median serum creatinine in survivors and non-survivors was 3.95 mg/dl (2.63 - 5.28 and 2.75 mg/dl (1.81 - 3.69, respectively. In the multivariable models, oliguria and serum urea were positively associated with dialysis; otherwise, a lower serum creatinine at first consultation was independently associated with higher mortality. Conclusion: In a cohort of septic AKI, oliguria and serum urea were the main indications for dialysis. We also described an inverse association between serum creatinine and mortality. Potential explanations for this finding include: delay in diagnosis, fluid overload with hemodilution of serum creatinine or poor nutritional status. This finding may also help to explain the low discriminative power of general severity scores - that assign higher risks to higher creatinine levels - in septic AKI patients.

Inverse association between plasma homocysteine concentrations and type 2 diabetes mellitus among a middle-aged and elderly Chinese population.

Science.gov (United States)

Yu, C; Wang, J; Wang, F; Han, X; Hu, H; Yuan, J; Miao, X; Yao, P; Wei, S; Wang, Y; Liang, Y; Chen, W; Zhang, X; Guo, H; Yang, H; Tang, Y; Zheng, D; Wu, T; He, M

2018-03-01

Plasma homocysteine concentrations have been reported to be associated with type 2 diabetes mellitus (T2DM) with controversial findings. The aim of the present study was to investigate the association between plasma homocysteine concentrations and T2DM. A cross-sectional study including 19,085 eligible participants derived from the Dongfeng-Tongji cohort was conducted. Plasma homocysteine concentrations were measured by Abbott Architect i2000 Automatic analyzer and T2DM was defined according to American Diabetes Association criteria. Logistic regression model was used to explore the association between plasma homocysteine concentrations and T2DM. The prevalence of T2DM was 19.0% in the whole population (mean age 62.9 years), 21.8% in males, and 17.1% in females. In the multivariable logistic regression analyses, compared with those in the lowest quintile, the OR (95% CI) of T2DM was 1.05 (0.92-1.21), 0.99 (0.86-1.14), 0.90 (0.78-1.05), and 0.77 (0.66-0.90) for quintile 2 to quintile 5 of homocysteine concentrations after adjustment for potential confounders (P for trend associated with decreased T2DM prevalence risk (OR = 0.88 per SD increase of homocysteine concentration; 95% CI: 0.84-0.93). A significant interaction between homocysteine concentrations and drinking status on T2DM prevalence risk was observed (P for interaction = 0.03). The inverse association of plasma homocysteine concentrations with T2DM prevalence risk was observed in non-drinkers but not in current drinkers. Plasma homocysteine concentrations were inversely correlated with T2DM among a middle-aged and elderly Chinese population. Copyright © 2017 The Italian Society of Diabetology, the Italian Society for the Study of Atherosclerosis, the Italian Society of Human Nutrition, and the Department of Clinical Medicine and Surgery, Federico II University. Published by Elsevier B.V. All rights reserved.

Non-local currents in 2D QFT: an alternative To - the quantum inverse scattering method

International Nuclear Information System (INIS)

Bernard, D.; Leclair, A.; Cornell Univ., Ithaca, NY

1990-01-01

The formalism based on non-local charges that we propose provides an alternative to the quantum inverse scattering method for solving integrable quantum field theories in 2D. The content of the paper is: 1. Introduction: historical background. 2. The NLC approach to 2D QFT: a summary. 3 Exchange algebras and on-shell conservation laws: why non-local charges are useful. 4. The lattice construction: the geometrical origin of non-local conserved currents. 5. The continuum construction: how to deal with non-local conserved currents. 6. Examples: Yangian and quantum group currents. 7 Conclusions: open problems. 22 refs., 4 figs

On the internal stability of non-linear dynamic inversion: application to flight control

Czech Academy of Sciences Publication Activity Database

Alam, M.; Čelikovský, Sergej

2017-01-01

Roč. 11, č. 12 (2017), s. 1849-1861 ISSN 1751-8644 R&D Projects: GA ČR(CZ) GA17-04682S Institutional support: RVO:67985556 Keywords : flight control * non-linear dynamic inversion * stability Subject RIV: BC - Control Systems Theory OBOR OECD: Automation and control systems Impact factor: 2.536, year: 2016 http://library.utia.cas.cz/separaty/2017/TR/celikovsky-0476150.pdf

Inverse associations of outdoor activity and vitamin D intake with the risk of Parkinson's disease.

Science.gov (United States)

Zhu, Dan; Liu, Gui-you; Lv, Zheng; Wen, Shi-rong; Bi, Sheng; Wang, Wei-zhi

2014-10-01

Early studies had suggested that vitamin D intake was inversely associated with neurodegenerative diseases, such as Alzheimer's disease and multiple sclerosis. However, the associations of vitamin D intake and outdoor activities with Parkinson's disease (PD) are still unclear, so this study is to evaluate these relationships from a case-control study in elderly Chinese. The study population involved 209 cases with new onsets of PD and 210 controls without neurodegenerative diseases. The data on dietary vitamin D and outdoor activities were collected using a food-frequency questionnaire and self-report questionnaire. Multivariable logistic regressions were used to examine the associations between dietary outdoor activities, vitamin D intake and PD. Adjustment was made for sex, age, smoking, alcohol use, education, and body mass index (BMI). Adjusted odds ratios (ORs) for PD in quartiles for outdoor physical activity were 1 (reference), 0.739 (0.413, 1.321), 0.501 (0.282, 0.891), and 0.437 (0.241, 0.795), respectively (P=0.002 for trend). Adjusted ORs for PD in quartiles for total vitamin D intake were 1 (reference), 0.647 (0.357, 1.170), 0.571 (0.318, 1.022), and 0.538 (0.301, 0.960), respectively (P=0.011 for trend). Our study suggested that outdoor activity and total vitamin D intake were inversely associated with PD, and outdoor activity seems to be more significantly associated with decreased risk for PD.

Inverse analysis of non-uniform temperature distributions using multispectral pyrometry

Science.gov (United States)

Fu, Tairan; Duan, Minghao; Tian, Jibin; Shi, Congling

2016-05-01

Optical diagnostics can be used to obtain sub-pixel temperature information in remote sensing. A multispectral pyrometry method was developed using multiple spectral radiation intensities to deduce the temperature area distribution in the measurement region. The method transforms a spot multispectral pyrometer with a fixed field of view into a pyrometer with enhanced spatial resolution that can give sub-pixel temperature information from a "one pixel" measurement region. A temperature area fraction function was defined to represent the spatial temperature distribution in the measurement region. The method is illustrated by simulations of a multispectral pyrometer with a spectral range of 8.0-13.0 μm measuring a non-isothermal region with a temperature range of 500-800 K in the spot pyrometer field of view. The inverse algorithm for the sub-pixel temperature distribution (temperature area fractions) in the "one pixel" verifies this multispectral pyrometry method. The results show that an improved Levenberg-Marquardt algorithm is effective for this ill-posed inverse problem with relative errors in the temperature area fractions of (-3%, 3%) for most of the temperatures. The analysis provides a valuable reference for the use of spot multispectral pyrometers for sub-pixel temperature distributions in remote sensing measurements.

Comparison of forward planning with automated inverse planning for three-dimensional conformal radiotherapy of non-small cell lung cancer without IMRT

International Nuclear Information System (INIS)

Mendes, Ruheena; Lavrenkov, Konstantin; Bedford, James L.; Henrys, Anthony; Ashley, Sue; Brada, Michael

2006-01-01

The forward and inverse treatment plans of 10 patients with lung cancer were compared in terms of PTV coverage, sparing of normal lung and time required to generate a plan. The inverse planning produced as good treatment plans as an experienced dosimetrist with considerable reduction in staff time. When translated to other complex sites, inverse non-IMRT planning may have considerable impact on manpower requirements

Estimation of biological parameters of marine organisms using linear and nonlinear acoustic scattering model-based inversion methods.

Science.gov (United States)

Chu, Dezhang; Lawson, Gareth L; Wiebe, Peter H

2016-05-01

The linear inversion commonly used in fisheries and zooplankton acoustics assumes a constant inversion kernel and ignores the uncertainties associated with the shape and behavior of the scattering targets, as well as other relevant animal parameters. Here, errors of the linear inversion due to uncertainty associated with the inversion kernel are quantified. A scattering model-based nonlinear inversion method is presented that takes into account the nonlinearity of the inverse problem and is able to estimate simultaneously animal abundance and the parameters associated with the scattering model inherent to the kernel. It uses sophisticated scattering models to estimate first, the abundance, and second, the relevant shape and behavioral parameters of the target organisms. Numerical simulations demonstrate that the abundance, size, and behavior (tilt angle) parameters of marine animals (fish or zooplankton) can be accurately inferred from the inversion by using multi-frequency acoustic data. The influence of the singularity and uncertainty in the inversion kernel on the inversion results can be mitigated by examining the singular values for linear inverse problems and employing a non-linear inversion involving a scattering model-based kernel.

Methylation of SOCS3 is inversely associated with metabolic syndrome in an epigenome-wide association study of obesity.

Science.gov (United States)

Ali, Omar; Cerjak, Diana; Kent, Jack W; James, Roland; Blangero, John; Carless, Melanie A; Zhang, Yi

2016-09-01

Epigenetic mechanisms, including DNA methylation, mediate the interaction between gene and environment and may play an important role in the obesity epidemic. We assessed the relationship between DNA methylation and obesity in peripheral blood mononuclear cells (PBMCs) at 485,000 CpG sites across the genome in family members (8-90 y of age) using a discovery cohort (192 individuals) and a validation cohort (1,052 individuals) of Northern European ancestry. After Bonferroni-correction (P α=0.05 = 1.31 × 10 -7 ) for genome-wide significance, we identified 3 loci, cg18181703 (SOCS3), cg04502490 (ZNF771), and cg02988947 (LIMD2), where methylation status was associated with body mass index percentile (BMI%), a clinical index for obesity in children, adolescents, and adults. These sites were also associated with multiple metabolic syndrome (MetS) traits, including central obesity, fat depots, insulin responsiveness, and plasma lipids. The SOCS3 methylation locus was also associated with the clinical definition of MetS. In the validation cohort, SOCS3 methylation status was found to be inversely associated with BMI% (P = 1.75 × 10 -6 ), waist to height ratio (P = 4.18 × 10 -7 ), triglycerides (P = 4.01 × 10 -4 ), and MetS (P = 4.01 × 10 -7 ), and positively correlated with HDL-c (P = 4.57 × 10 -8 ). Functional analysis in a sub cohort (333 individuals) demonstrated SOCS3 methylation and gene expression in PBMCs were inversely correlated (P = 2.93 × 10 -4 ) and expression of SOCS3 was positively correlated with status of MetS (P = 0.012). We conclude that epigenetic modulation of SOCS3, a gene involved in leptin and insulin signaling, may play an important role in obesity and MetS.

PREFACE: First International Congress of the International Association of Inverse Problems (IPIA): Applied Inverse Problems 2007: Theoretical and Computational Aspects

Science.gov (United States)

Uhlmann, Gunther

2008-07-01

This volume represents the proceedings of the fourth Applied Inverse Problems (AIP) international conference and the first congress of the Inverse Problems International Association (IPIA) which was held in Vancouver, Canada, June 25 29, 2007. The organizing committee was formed by Uri Ascher, University of British Columbia, Richard Froese, University of British Columbia, Gary Margrave, University of Calgary, and Gunther Uhlmann, University of Washington, chair. The conference was part of the activities of the Pacific Institute of Mathematical Sciences (PIMS) Collaborative Research Group on inverse problems (http://www.pims.math.ca/scientific/collaborative-research-groups/past-crgs). This event was also supported by grants from NSF and MITACS. Inverse Problems (IP) are problems where causes for a desired or an observed effect are to be determined. They lie at the heart of scientific inquiry and technological development. The enormous increase in computing power and the development of powerful algorithms have made it possible to apply the techniques of IP to real-world problems of growing complexity. Applications include a number of medical as well as other imaging techniques, location of oil and mineral deposits in the earth's substructure, creation of astrophysical images from telescope data, finding cracks and interfaces within materials, shape optimization, model identification in growth processes and, more recently, modelling in the life sciences. The series of Applied Inverse Problems (AIP) Conferences aims to provide a primary international forum for academic and industrial researchers working on all aspects of inverse problems, such as mathematical modelling, functional analytic methods, computational approaches, numerical algorithms etc. The steering committee of the AIP conferences consists of Heinz Engl (Johannes Kepler Universität, Austria), Joyce McLaughlin (RPI, USA), William Rundell (Texas A&M, USA), Erkki Somersalo (Helsinki University of Technology

NON-LTE INVERSIONS OF THE Mg ii h and k AND UV TRIPLET LINES

Energy Technology Data Exchange (ETDEWEB)

De la Cruz Rodríguez, Jaime; Leenaarts, Jorrit [Institute for Solar Physics, Dept. of Astronomy, Stockholm University, AlbaNova University Centre, SE-106 91 Stockholm Sweden (Sweden); Ramos, Andrés Asensio [Instituto de Astrofísica de Canarias, E-38205, La Laguna, Tenerife (Spain)

2016-10-20

The Mg ii h and k lines are powerful diagnostics for studying the solar chromosphere. They have become particularly popular with the launch of the Interface Region Imaging Spectrograph ( IRIS ) satellite, and a number of studies that include these lines have lead to great progress in understanding chromospheric heating, in many cases thanks to the support from 3D MHD simulations. In this study, we utilize another approach to analyze observations: non-LTE inversions of the Mg ii h and k and UV triplet lines including the effects of partial redistribution. Our inversion code attempts to construct a model atmosphere that is compatible with the observed spectra. We have assessed the capabilities and limitations of the inversions using the FALC atmosphere and a snapshot from a 3D radiation-MHD simulation. We find that Mg ii h and k allow reconstructing a model atmosphere from the middle photosphere to the transition region. We have also explored the capabilities of a multi-line/multi-atom setup, including the Mg ii h and k, the Ca ii 854.2 nm, and the Fe i 630.25 lines to recover the full stratification of physical parameters, including the magnetic field vector, from the photosphere to the chromosphere. Finally, we present the first inversions of observed IRIS spectra from quiet-Sun, plage, and sunspot, with very promising results.

A higher level of education amplifies the inverse association between income and disability in the Spanish elderly.

Science.gov (United States)

Abellán, Antonio; Rodríguez-Laso, Ángel; Pujol, Rogelio; Barrios, Laura

2015-12-01

This paper aims to estimate if the education level modifies the association of income with disability prevalence in the elderly. Education can have a confounding effect on income or interact with it as a health determinant. It is important to analyze the relationship between socio-economic status and disability in older people, because it helps to better understand health inequalities and organize appropriate social policies. The study is based on the Survey on Disability, Personal Autonomy and Dependency Situations (Spanish National Statistics Institute). Binary logistic regression models are adjusted (bivariate, adjusted for gender and age, with all variables and with the interaction between income and education levels). A bad adjustment of the model is detected and a scobit link is added, which helps to differentiate disabled and non-disabled individuals better. People with difficulty in carrying out activities of daily living are much older, frequently women and with low education and income levels. The significant interaction between education level and income means that the odds of being disabled is 43% less in people of high income compared with people of low income if they are well educated, while it is only 21%, among those with low education. A higher education level amplifies significantly the inverse association between income and disability in the Spanish elderly, what suggests that those with higher education will profit more than those with lower education from universal economic benefits policies aimed at the disabled, increasing health inequalities between groups.

Statistical perspectives on inverse problems

DEFF Research Database (Denmark)

Andersen, Kim Emil

of the interior of an object from electrical boundary measurements. One part of this thesis concerns statistical approaches for solving, possibly non-linear, inverse problems. Thus inverse problems are recasted in a form suitable for statistical inference. In particular, a Bayesian approach for regularisation...... problem is given in terms of probability distributions. Posterior inference is obtained by Markov chain Monte Carlo methods and new, powerful simulation techniques based on e.g. coupled Markov chains and simulated tempering is developed to improve the computational efficiency of the overall simulation......Inverse problems arise in many scientific disciplines and pertain to situations where inference is to be made about a particular phenomenon from indirect measurements. A typical example, arising in diffusion tomography, is the inverse boundary value problem for non-invasive reconstruction...

High rates of de novo 15q11q13 inversions in human spermatozoa

Directory of Open Access Journals (Sweden)

Molina Òscar

2012-02-01

Full Text Available Abstract Low-Copy Repeats predispose the 15q11-q13 region to non-allelic homologous recombination. We have already demonstrated that a significant percentage of Prader-Willi syndrome (PWS fathers have an increased susceptibility to generate 15q11q13 deletions in spermatozoa, suggesting the participation of intrachromatid exchanges. This work has been focused on assessing the incidence of de novo 15q11q13 inversions in spermatozoa of control donors and PWS fathers in order to determine the basal rates of inversions and to confirm the intrachromatid mechanism as the main cause of 15q11q13 anomalies. Semen samples from 10 control donors and 16 PWS fathers were processed and analyzed by triple-color FISH. Three differentially labeled BAC-clones were used: one proximal and two distal of the 15q11-q13 region. Signal associations allowed the discrimination between normal and inverted haplotypes, which were confirmed by laser-scanning confocal microscopy. Two types of inversions were detected which correspond to the segments involved in Class I and II PWS deletions. No significant differences were observed in the mean frequencies of inversions between controls and PWS fathers (3.59% ± 0.46 and 9.51% ± 0.87 vs 3.06% ± 0.33 and 10.07% ± 0.74. Individual comparisons showed significant increases of inversions in four PWS fathers (P Results suggest that the incidence of heterozygous inversion carriers in the general population could reach significant values. This situation could have important implications, as they have been described as predisposing haplotypes for genomic disorders. As a whole, results confirm the high instability of the 15q11-q13 region, which is prone to different types of de novo reorganizations by intrachromatid NAHR.

Causal role for inverse reasoning on obsessive-compulsive symptoms: Preliminary evidence from a cognitive bias modification for interpretation bias study.

Science.gov (United States)

Wong, Shiu F; Grisham, Jessica R

2017-12-01

The inference-based approach (IBA) is a cognitive account of the genesis and maintenance of obsessive-compulsive disorder (OCD). According to the IBA, individuals with OCD are prone to using inverse reasoning, in which hypothetical causes form the basis of conclusions about reality. Several studies have provided preliminary support for an association between features of the IBA and OCD symptoms. However, there are currently no studies that have investigated the proposed causal relationship of inverse reasoning in OCD. In a non-clinical sample (N = 187), we used an interpretive cognitive bias procedure to train a bias towards using inverse reasoning (n = 64), healthy sensory-based reasoning (n = 65), or a control condition (n = 58). Participants were randomly allocated to these training conditions. This manipulation allowed us to assess whether, consistent with the IBA, inverse reasoning training increased compulsive-like behaviours and self-reported OCD symptoms. Results indicated that compared to a control condition, participants trained in inverse reasoning reported more OCD symptoms and were more avoidant of potentially contaminated objects. Moreover, change in inverse reasoning bias was a small but significant mediator of the relationship between training condition and behavioural avoidance. Conversely, training in a healthy (non-inverse) reasoning style did not have any effect on symptoms or behaviour relative to the control condition. As this study was conducted in a non-clinical sample, we were unable to generalise our findings to a clinical population. Findings generally support the IBA model by providing preliminary evidence of a causal role for inverse reasoning in OCD. Copyright © 2017 Elsevier Ltd. All rights reserved.

Characterization of the chromosomal inversion associated with the Koa mutation in the mouse revealed the cause of skeletal abnormalities

Directory of Open Access Journals (Sweden)

Suzuki Hiroetsu

2009-09-01

Full Text Available Abstract Background Koala (Koa is a dominant mutation in mice causing bushy muzzle and pinna, and is associated with a chromosomal inversion on the distal half of chromosome 15. To identify the gene responsible for the Koa phenotypes, we investigated phenotypes of Koa homozygous mice and determined the breakpoints of the inversion with a genetic method using recombination between two different chromosomal inversions. Results Skeletal preparation of Koa homozygotes showed marked deformity of the ribs and a wider skull with extended zygomatic arches, in addition to a general reduction in the lengths of long bones. They also had open eyelids at birth caused by a defect in the extension of eyelid anlagen during the embryonic stages. The proximal and distal breakpoints of the Koa inversion were determined to be 0.8-Mb distal to the Trsps1 gene and to 0.1-Mb distal to the Hoxc4 gene, respectively, as previously reported. The phenotypes of mice with the recombinant inverted chromosomes revealed the localization of the gene responsible the Koa phenotype in the vicinity of the proximal recombinant breakpoint. Expression of the Trsps1 gene in this region was significantly reduced in the Koa homozygous and heterozygous embryos. Conclusion While no gene was disrupted by the chromosomal inversion, an association between the Koa phenotype and the proximal recombinant breakpoint, phenotypic similarities with Trps1-deficient mice or human patients with TRSP1 mutations, and the reduced expression of the Trsps1 gene in Koa mice, indicated that the phenotypes of the Koa mice are caused by the altered expression of the Trps1 gene.

Non puerperal uterine inversion in a young female- a case report.

Science.gov (United States)

Rathod, Setu; Samal, Sunil Kumar; Pallavee, P; Ghose, Seetesh

2014-09-01

We report a case of 28-year-old, primipara who presented with complaints of mass descending per vaginum along with excessive bleeding and foul smelling vaginal discharge for the past six months. Clinical examination revealed an inverted uterus, cervix and vagina with a large submucosal fundal fibroid. A diagnosis of non-puerperal uterine inversion was made. Surgical management included vaginal myomectomy with repositioning of the uterus using an abdomino-vaginal approach and a successful outcome. Histopathology confirmed the diagnosis of leiomyoma. Hence, we conclude that uterus-sparing surgery should be considered in young females desirous for future pregnancy until the final pathology is known.

Solar radiation is inversely associated with inflammatory bowel disease admissions.

Science.gov (United States)

Jaime, Francisca; Riutort, Maria C; Alvarez-Lobos, Manuel; Hoyos-Bachiloglu, Rodrigo; Camargo, Carlos A; Borzutzky, Arturo

To explore the associations between latitude and solar radiation with inflammatory bowel disease admission rates in Chile, the country with the largest variation in solar radiation in the world. This is an ecological study, which included data on all hospital-admitted population for inflammatory bowel disease between 2001 and 2012, according to different latitudes and solar radiation exposures in Chile. The data were acquired from the national hospital discharge database from the Department of Health Statistics and Information of the Chilean Ministry of Health. Between 2001 and 2012 there were 12,869 admissions due to inflammatory bowel disease (69% ulcerative colitis, 31% Crohn's disease). Median age was 36 years (IQR: 25-51); 57% were female. The national inflammatory bowel disease admission rate was 6.52 (95% CI: 6.40-6.63) per 100,000 inhabitants with increasing rates over the 12-year period. In terms of latitude, the highest admission rates for pediatric ulcerative colitis and Crohn's disease, as well as adult ulcerative colitis, were observed in the southernmost region with lowest annual solar radiation. Linear regression analysis showed that regional solar radiation was inversely associated with inflammatory bowel disease admissions in Chile (β: -.44, p = .03). Regional solar radiation was inversely associated with inflammatory bowel disease admission rates in Chile; inflammatory bowel disease admissions were highest in the southernmost region with lowest solar radiation. Our results support the potential role of vitamin D deficiency on inflammatory bowel disease flares.

Prostate cancer incidence in Australia correlates inversely with solar radiation.

Science.gov (United States)

Loke, Tim W; Seyfi, Doruk; Sevfi, Doruk; Khadra, Mohamed

2011-11-01

What's known on the subject? and What does the study add? Increased sun exposure and blood levels of vitamin D have been postulated to be protective against prostate cancer. This is controversial. We investigated the relationship between prostate cancer incidence and solar radiation in non-urban Australia, and found a lower incidence in regions receiving more sunlight. In landmark ecological studies, prostate cancer mortality rates have been shown to be inversely related to ultraviolet radiation exposure. Investigators have hypothesised that ultraviolet radiation acts by increasing production of vitamin D, which inhibits prostate cancer cells in vitro. However, analyses of serum levels of vitamin D in men with prostate cancer have failed to support this hypothesis. This study has found an inverse correlation between solar radiation and prostate cancer incidence in Australia. Our population (previously unstudied) represents the third group to exhibit this correlation. Significantly, the demographics and climate of Australia differ markedly from those of previous studies conducted on men in the United Kingdom and the United States. • To ascertain if prostate cancer incidence rates correlate with solar radiation among non-urban populations of men in Australia. • Local government areas from each state and territory were selected using explicit criteria. Urban areas were excluded from analysis. • For each local government area, prostate cancer incidence rates and averaged long-term solar radiation were obtained. • The strength of the association between prostate cancer incidence and solar radiation was determined. • Among 70 local government areas of Australia, age-standardized prostate cancer incidence rates for the period 1998-2007 correlated inversely with daily solar radiation averaged over the last two decades. •  There exists an association between less solar radiation and higher prostate cancer incidence in Australia. © 2011 THE AUTHORS. BJU

Inverse Association of Parkinson Disease With Systemic Lupus Erythematosus: A Nationwide Population-based Study.

Science.gov (United States)

Liu, Feng-Cheng; Huang, Wen-Yen; Lin, Te-Yu; Shen, Chih-Hao; Chou, Yu-Ching; Lin, Cheng-Li; Lin, Kuen-Tze; Kao, Chia-Hung

2015-11-01

The effects of the inflammatory mediators involved in systemic lupus erythematous (SLE) on subsequent Parkinson disease have been reported, but no relevant studies have focused on the association between the 2 diseases. This nationwide population-based study evaluated the risk of Parkinson disease in patients with SLE.We identified 12,817 patients in the Taiwan National Health Insurance database diagnosed with SLE between 2000 and 2010 and compared the incidence rate of Parkinson disease among these patients with that among 51,268 randomly selected age and sex-matched non-SLE patients. A Cox multivariable proportional-hazards model was used to evaluate the risk factors of Parkinson disease in the SLE cohort.We observed an inverse association between a diagnosis of SLE and the risk of subsequent Parkinson disease, with the crude hazard ratio (HR) being 0.60 (95% confidence interval 0.45-0.79) and adjusted HR being 0.68 (95% confidence interval 0.51-0.90). The cumulative incidence of Parkinson disease was 0.83% lower in the SLE cohort than in the non-SLE cohort. The adjusted HR of Parkinson disease decreased as the follow-up duration increased and was decreased among older lupus patients with comorbidity.We determined that patients with SLE had a decreased risk of subsequent Parkinson disease. Further research is required to elucidate the underlying mechanism.

Solving Non-Isospectral mKdV Equation and Sine-Gordon Equation Hierarchies with Self-Consistent Sources via Inverse Scattering Transform

International Nuclear Information System (INIS)

Li Qi; Zhang Dajun; Chen Dengyuan

2010-01-01

N-soliton solutions of the hierarchy of non-isospectral mKdV equation with self-consistent sources and the hierarchy of non-isospectral sine-Gordon equation with self-consistent sources are obtained via the inverse scattering transform. (general)

Wave-equation dispersion inversion

KAUST Repository

Li, Jing

2016-12-08

We present the theory for wave-equation inversion of dispersion curves, where the misfit function is the sum of the squared differences between the wavenumbers along the predicted and observed dispersion curves. The dispersion curves are obtained from Rayleigh waves recorded by vertical-component geophones. Similar to wave-equation traveltime tomography, the complicated surface wave arrivals in traces are skeletonized as simpler data, namely the picked dispersion curves in the phase-velocity and frequency domains. Solutions to the elastic wave equation and an iterative optimization method are then used to invert these curves for 2-D or 3-D S-wave velocity models. This procedure, denoted as wave-equation dispersion inversion (WD), does not require the assumption of a layered model and is significantly less prone to the cycle-skipping problems of full waveform inversion. The synthetic and field data examples demonstrate that WD can approximately reconstruct the S-wave velocity distributions in laterally heterogeneous media if the dispersion curves can be identified and picked. The WD method is easily extended to anisotropic data and the inversion of dispersion curves associated with Love waves.

Gene alterations at Drosophila inversion breakpoints provide prima facie evidence for natural selection as an explanation for rapid chromosomal evolution.

Science.gov (United States)

Guillén, Yolanda; Ruiz, Alfredo

2012-02-01

Chromosomal inversions have been pervasive during the evolution of the genus Drosophila, but there is significant variation between lineages in the rate of rearrangement fixation. D. mojavensis, an ecological specialist adapted to a cactophilic niche under extreme desert conditions, is a chromosomally derived species with ten fixed inversions, five of them not present in any other species. In order to explore the causes of the rapid chromosomal evolution in D. mojavensis, we identified and characterized all breakpoints of seven inversions fixed in chromosome 2, the most dynamic one. One of the inversions presents unequivocal evidence for its generation by ectopic recombination between transposon copies and another two harbor inverted duplications of non-repetitive DNA at the two breakpoints and were likely generated by staggered single-strand breaks and repair by non-homologous end joining. Four out of 14 breakpoints lay in the intergenic region between preexisting duplicated genes, suggesting an adaptive advantage of separating previously tightly linked duplicates. Four out of 14 breakpoints are associated with transposed genes, suggesting these breakpoints are fragile regions. Finally two inversions contain novel genes at their breakpoints and another three show alterations of genes at breakpoints with potential adaptive significance. D. mojavensis chromosomal inversions were generated by multiple mechanisms, an observation that does not provide support for increased mutation rate as explanation for rapid chromosomal evolution. On the other hand, we have found a number of gene alterations at the breakpoints with putative adaptive consequences that directly point to natural selection as the cause of D. mojavensis rapid chromosomal evolution.

Gene alterations at Drosophila inversion breakpoints provide prima facie evidence for natural selection as an explanation for rapid chromosomal evolution

Directory of Open Access Journals (Sweden)

Guillén Yolanda

2012-02-01

Full Text Available Abstract Background Chromosomal inversions have been pervasive during the evolution of the genus Drosophila, but there is significant variation between lineages in the rate of rearrangement fixation. D. mojavensis, an ecological specialist adapted to a cactophilic niche under extreme desert conditions, is a chromosomally derived species with ten fixed inversions, five of them not present in any other species. Results In order to explore the causes of the rapid chromosomal evolution in D. mojavensis, we identified and characterized all breakpoints of seven inversions fixed in chromosome 2, the most dynamic one. One of the inversions presents unequivocal evidence for its generation by ectopic recombination between transposon copies and another two harbor inverted duplications of non-repetitive DNA at the two breakpoints and were likely generated by staggered single-strand breaks and repair by non-homologous end joining. Four out of 14 breakpoints lay in the intergenic region between preexisting duplicated genes, suggesting an adaptive advantage of separating previously tightly linked duplicates. Four out of 14 breakpoints are associated with transposed genes, suggesting these breakpoints are fragile regions. Finally two inversions contain novel genes at their breakpoints and another three show alterations of genes at breakpoints with potential adaptive significance. Conclusions D. mojavensis chromosomal inversions were generated by multiple mechanisms, an observation that does not provide support for increased mutation rate as explanation for rapid chromosomal evolution. On the other hand, we have found a number of gene alterations at the breakpoints with putative adaptive consequences that directly point to natural selection as the cause of D. mojavensis rapid chromosomal evolution.

Gene alterations at Drosophila inversion breakpoints provide prima facie evidence for natural selection as an explanation for rapid chromosomal evolution

Science.gov (United States)

2012-01-01

Background Chromosomal inversions have been pervasive during the evolution of the genus Drosophila, but there is significant variation between lineages in the rate of rearrangement fixation. D. mojavensis, an ecological specialist adapted to a cactophilic niche under extreme desert conditions, is a chromosomally derived species with ten fixed inversions, five of them not present in any other species. Results In order to explore the causes of the rapid chromosomal evolution in D. mojavensis, we identified and characterized all breakpoints of seven inversions fixed in chromosome 2, the most dynamic one. One of the inversions presents unequivocal evidence for its generation by ectopic recombination between transposon copies and another two harbor inverted duplications of non-repetitive DNA at the two breakpoints and were likely generated by staggered single-strand breaks and repair by non-homologous end joining. Four out of 14 breakpoints lay in the intergenic region between preexisting duplicated genes, suggesting an adaptive advantage of separating previously tightly linked duplicates. Four out of 14 breakpoints are associated with transposed genes, suggesting these breakpoints are fragile regions. Finally two inversions contain novel genes at their breakpoints and another three show alterations of genes at breakpoints with potential adaptive significance. Conclusions D. mojavensis chromosomal inversions were generated by multiple mechanisms, an observation that does not provide support for increased mutation rate as explanation for rapid chromosomal evolution. On the other hand, we have found a number of gene alterations at the breakpoints with putative adaptive consequences that directly point to natural selection as the cause of D. mojavensis rapid chromosomal evolution. PMID:22296923

Non-steroidal anti-inflammatory drugs use is associated with reduced risk of inflammation-associated cancers: NIH-AARP study.

Directory of Open Access Journals (Sweden)

Fatma M Shebl

Full Text Available Chronic inflammation has been linked to cancers, and use of non-steroidal anti-inflammatory drugs (NSAIDs has been associated with reduced risk of several cancers. To further refine the magnitude of NSAID-related associations, in particular for cancers related to inflammation, such as alcohol-, infection-, obesity-, and smoking-related cancers, as well as for less common cancers, we evaluated the use of NSAIDs and cancer risk in a very large cohort. We used propensity scores to account for potential selection bias and hypothesized that NSAID use is associated with decreased cancer incidence.We conducted a prospective study among 314,522 participants in the NIH-AARP Diet and Health Study. Individuals who completed the lifestyle questionnaire, which included NSAID use, in 1996-1997 were followed through 2006. Information on cancer incidence was ascertained by linking to cancer registries and vital status databases.During 2,715,994 person-years of follow-up (median 10.1 person-years, there were 51,894 incident cancers. Compared with non-users of NSAIDs, individuals who reported use in the 12 months prior to interview had a significantly lower risk of all inflammation-related cancer, alcohol-related, infection-related, obesity-related, and smoking-related cancers [hazard ratio (HR (95% CI 0.90 (0.87-0.93, 0.80 (0.74-0.85, 0.82 (0.78-0.87, 0.88 (0.84-0.92, and 0.88 (0.85-0.92 respectively].After accounting for potential selection bias, our data showed an inverse association between NSAID use and alcohol-related, infection-related, obesity-related, and smoking-related cancers and support the hypothesis that inflammation is related to an increased risk of certain cancers.

Limits to Nonlinear Inversion

DEFF Research Database (Denmark)

Mosegaard, Klaus

2012-01-01

For non-linear inverse problems, the mathematical structure of the mapping from model parameters to data is usually unknown or partly unknown. Absence of information about the mathematical structure of this function prevents us from presenting an analytical solution, so our solution depends on our......-heuristics are inefficient for large-scale, non-linear inverse problems, and that the 'no-free-lunch' theorem holds. We discuss typical objections to the relevance of this theorem. A consequence of the no-free-lunch theorem is that algorithms adapted to the mathematical structure of the problem perform more efficiently than...... pure meta-heuristics. We study problem-adapted inversion algorithms that exploit the knowledge of the smoothness of the misfit function of the problem. Optimal sampling strategies exist for such problems, but many of these problems remain hard. © 2012 Springer-Verlag....

Segmental Duplication, Microinversion, and Gene Loss Associated with a Complex Inversion Breakpoint Region in Drosophila

Science.gov (United States)

Calvete, Oriol; González, Josefa; Betrán, Esther; Ruiz, Alfredo

2012-01-01

Chromosomal inversions are usually portrayed as simple two-breakpoint rearrangements changing gene order but not gene number or structure. However, increasing evidence suggests that inversion breakpoints may often have a complex structure and entail gene duplications with potential functional consequences. Here, we used a combination of different techniques to investigate the breakpoint structure and the functional consequences of a complex rearrangement fixed in Drosophila buzzatii and comprising two tandemly arranged inversions sharing the middle breakpoint: 2m and 2n. By comparing the sequence in the breakpoint regions between D. buzzatii (inverted chromosome) and D. mojavensis (noninverted chromosome), we corroborate the breakpoint reuse at the molecular level and infer that inversion 2m was associated with a duplication of a ∼13 kb segment and likely generated by staggered breaks plus repair by nonhomologous end joining. The duplicated segment contained the gene CG4673, involved in nuclear transport, and its two nested genes CG5071 and CG5079. Interestingly, we found that other than the inversion and the associated duplication, both breakpoints suffered additional rearrangements, that is, the proximal breakpoint experienced a microinversion event associated at both ends with a 121-bp long duplication that contains a promoter. As a consequence of all these different rearrangements, CG5079 has been lost from the genome, CG5071 is now a single copy nonnested gene, and CG4673 has a transcript ∼9 kb shorter and seems to have acquired a more complex gene regulation. Our results illustrate the complex effects of chromosomal rearrangements and highlight the need of complementing genomic approaches with detailed sequence-level and functional analyses of breakpoint regions if we are to fully understand genome structure, function, and evolutionary dynamics. PMID:22328714

Inverse modelling and pulsating torque minimization of salient pole non-sinusoidal synchronous machines

Energy Technology Data Exchange (ETDEWEB)

Ait-gougam, Y.; Ibtiouen, R.; Touhami, O. [Laboratoire de Recherche en Electrotechnique, Ecole Nationale Polytechnique, BP 182, El-Harrach 16200 (Algeria); Louis, J.-P.; Gabsi, M. [Systemes et Applications des Technologies de l' Information et de l' Energie (SATIE), CNRS UMR 8029, Ecole Normale Superieure de Cachan, 61 Avenue du President Wilson, 94235 Cachan Cedex (France)

2008-01-15

Sinusoidal motor's mathematical models are usually obtained using classical d-q transformation in the case of salient pole synchronous motors having sinusoidal field distribution. In this paper, a new inverse modelling for synchronous motors is presented. This modelling is derived from the properties of constant torque curves in the Concordia's reference frame. It takes into account the non-sinusoidal field distribution; EMF, self and mutual inductances having non-sinusoidal variations with respect to the angular rotor position. Both copper losses and torque ripples are minimized by adapted currents waveforms calculated from this model. Experimental evaluation was carried out on a DSP-controlled PMSM drive platform. Test results obtained demonstrate the effectiveness of the proposed method in reducing torque ripple. (author)

Free Triiodothyronine Concentrations are Inversely Associated with Elevated Carotid Intima-Media Thickness in Middle-Aged and Elderly Chinese Population.

Science.gov (United States)

Zhou, Yulin; Zhao, Liebin; Wang, Tiange; Hong, Jie; Zhang, Jie; Xu, Baihui; Huang, Xiaolin; Xu, Min; Bi, Yufang

2016-01-01

Increased carotid artery intima media thickness (C-IMT) is an early feature of atherosclerosis. It has been reported to be altered in patients with thyroid dysfunction, and the evidence is still controversial. The present study aimed to explore the relationship between C-IMT and possible variations in thyroid function in Chinese adults aged 40 years and above. A community-based cross-sectional study was conducted among 2276 non-diabetic participants. Serum free triiodothyronine (FT3), free thyroxine (FT4), and thyroid stimulating hormone (TSH) were determined by chemiluminescent microparticle immunoassay. The prevalence of elevated C-IMT decreased according to FT3 quartiles (29.8%, 24.3%, 24.2%, and 22.2%, P for trend=0.005). In both univariate and multivariate linear regression analyses, FT3 levels were inversely associated with C-IMT (both P values ≤ 0.002). Multivariate-adjusted logistic regression analysis showed that high FT3 levels were associated with low prevalent elevated C-IMT. The adjusted odds ratio for elevated C-IMT was 0.71 (95% confidence interval, 0.52-0.99, P=0.04) when comparing the highest with the lowest quartile of FT3. Serum FT3 levels were inversely associated with elevated C-IMT in middle-aged and elderly Chinese adults without diabetes, independent of traditional risk factors for atherosclerosis.

Physical activity inversely associated with the presence of depression among urban adolescents in regional China

Directory of Open Access Journals (Sweden)

Liang YaQiong

2009-05-01

Full Text Available Abstract Background An inverse relationship between physical activity (PA and depression among adolescents has been reported in developed communities without consideration of sedentary behaviors (SB, including sitting for course study, viewing TV, and sleeping. We explored the association between recreational PA time (hr/wk and depression after adjustment with SB and other possible confounders among Chinese adolescents. Methods A population-based cross-sectional study was conducted in Nanjing municipality of China in 2004 using a multi-stage cluster sampling approach. A total of 72 classes were randomly selected from 24 urban junior high schools and all students completed the structured questionnaire. Adolescent depression was examined by the Children's Depression Inventory (CDI of Chinese version with cutoff point value of 20 or above as the presence of depression. Recreational PA time was measured by a question on weekly hours of PA outside of school. Descriptive statistics, multivariate logistic and linear regression models were used in analysis. Results The overall prevalence of depression was 15.7% (95%CI: 14.3%, 17.1% among 2,444 eligible participants. It was found that physical activity was negatively associated with depression. After adjustment for sedentary behaviors and other potential confounders, participants who spent 1–7 hr/wk, 8–14 hr/wk and 15+ hr/wk for recreational PA, respectively, had odds ratios of 0.70 (95% CI = 0.57, 0.86, 0.68 (95% CI = 0.53, 0.88 and 0.66 (95% CI = 0.50, 0.87 for likelihood of being depressive, compared to their counterparts who spent 0–0.9 hr/wk for PA. This inverse relationship between PA time and depression remained statistically significant by gender and grade. Conclusion This study, conducted among Chinese adolescents, strengthened the evidence that physical activity was inversely associated with depression. Our study has important implications for health officers and public health

Inverse association between yoghurt intake and upper aerodigestive tract cancer risk in a Japanese population.

Science.gov (United States)

Kawakita, Daisuke; Sato, Fumihito; Hosono, Satoyo; Ito, Hidemi; Oze, Isao; Watanabe, Miki; Hanai, Nobuhiro; Hatooka, Shunzo; Hasegawa, Yasuhisa; Shinoda, Masayuki; Tajima, Kazuo; Murakami, Shingo; Tanaka, Hideo; Matsuo, Keitaro

2012-09-01

Although the combination of tobacco smoking and alcohol drinking account for approximately 80% of upper aerodigestive tract (UADT) cancer risk, the role of dietary factors, including dairy products, in the risk of these cancers remains controversial. We aimed to evaluate the association between dairy product intake and UADT cancer risk in a Japanese population. We conducted a case-control study in 959 patients with UADT cancer and 2877 sex- and age-matched noncancer control subjects who visited the Aichi Cancer Center in Nagoya, Japan. Data on lifestyle factors, including diet, were obtained by self-administered questionnaire. Associations were assessed by multivariate logistic regression models that considered potential confounders. We found a significant inverse association between yoghurt intake and UADT cancer risk with multivariate-adjusted odds ratios and 95% confidence intervals for <1 time/week, ≥ 1 time/week and <1 time/day, and ≥ 1 time/day consumption of yoghurt of 0.70 (95% confidence interval: 0.54-0.91), 0.67 (0.54-0.84), and 0.73 (0.55-0.95) relative to nonconsumers (P trend=0.005). When stratified by primary tumor site, this association was significant among patients with hypopharyngeal, laryngeal, and esophageal cancer. However, we saw no significant association between milk or butter intake and UADT cancer risk. In this study, we found that a high intake of yoghurt may lower the risk of developing UADT cancer in a Japanese population. Further investigation of this association is warranted.

Inverse scattering problems with multi-frequencies

International Nuclear Information System (INIS)

Bao, Gang; Li, Peijun; Lin, Junshan; Triki, Faouzi

2015-01-01

This paper is concerned with computational approaches and mathematical analysis for solving inverse scattering problems in the frequency domain. The problems arise in a diverse set of scientific areas with significant industrial, medical, and military applications. In addition to nonlinearity, there are two common difficulties associated with the inverse problems: ill-posedness and limited resolution (diffraction limit). Due to the diffraction limit, for a given frequency, only a low spatial frequency part of the desired parameter can be observed from measurements in the far field. The main idea developed here is that if the reconstruction is restricted to only the observable part, then the inversion will become stable. The challenging task is how to design stable numerical methods for solving these inverse scattering problems inspired by the diffraction limit. Recently, novel recursive linearization based algorithms have been presented in an attempt to answer the above question. These methods require multi-frequency scattering data and proceed via a continuation procedure with respect to the frequency from low to high. The objective of this paper is to give a brief review of these methods, their error estimates, and the related mathematical analysis. More attention is paid to the inverse medium and inverse source problems. Numerical experiments are included to illustrate the effectiveness of these methods. (topical review)

QCD-instantons and conformal inversion symmetry

Energy Technology Data Exchange (ETDEWEB)

Klammer, D.

2006-07-15

Instantons are an essential and non-perturbative part of Quantum Chromodynamics, the theory of strong interactions. One of the most relevant quantities in the instanton calculus is the instanton-size distribution, which can be described on the one hand within the framework of instanton perturbation theory and on the other hand investigated numerically by means of lattice computations. A rapid onset of a drastic discrepancy between these respective results indicates that the underlying physics is not yet well understood. In this work we investigate the appealing possibility of a symmetry under conformal inversion of space-time leading to this deviation. The motivation being that the lattice data seem to be invariant under an inversion of the instanton size. Since the instanton solution of a given size turns into an anti-instanton solution having an inverted size under conformal inversion of space-time, we ask in a first investigation, whether this property is transferred to the quantum level. In order to introduce a new scale, which is indicated by the lattice data and corresponds to the average instanton size as inversion radius, we project the instanton calculus onto the four-dimensional surface of a five-dimensional sphere via stereographic projection. The radius of this sphere is associated with the average instanton size. The result for the instanton size-distribution projected onto the sphere agrees surprisingly well with the lattice data at qualitative level. The resulting symmetry under an inversion of the instanton size is almost perfect. (orig.)

QCD-instantons and conformal inversion symmetry

International Nuclear Information System (INIS)

Klammer, D.

2006-07-01

Instantons are an essential and non-perturbative part of Quantum Chromodynamics, the theory of strong interactions. One of the most relevant quantities in the instanton calculus is the instanton-size distribution, which can be described on the one hand within the framework of instanton perturbation theory and on the other hand investigated numerically by means of lattice computations. A rapid onset of a drastic discrepancy between these respective results indicates that the underlying physics is not yet well understood. In this work we investigate the appealing possibility of a symmetry under conformal inversion of space-time leading to this deviation. The motivation being that the lattice data seem to be invariant under an inversion of the instanton size. Since the instanton solution of a given size turns into an anti-instanton solution having an inverted size under conformal inversion of space-time, we ask in a first investigation, whether this property is transferred to the quantum level. In order to introduce a new scale, which is indicated by the lattice data and corresponds to the average instanton size as inversion radius, we project the instanton calculus onto the four-dimensional surface of a five-dimensional sphere via stereographic projection. The radius of this sphere is associated with the average instanton size. The result for the instanton size-distribution projected onto the sphere agrees surprisingly well with the lattice data at qualitative level. The resulting symmetry under an inversion of the instanton size is almost perfect. (orig.)

An Inverse Association between Mediterranean- Like Dietary Pattern and Blood Pressure in Male, But Not Female, Adults in Shiraz

Directory of Open Access Journals (Sweden)

Farideh Dastsouz

2016-01-01

Full Text Available Background: Dietary pattern is an effective way of studying the effect of diet on diseases. We investigated the association between dietary patterns and blood pressure (BP in adults aged 20-50 years. Methods: In a cross-sectional design, 418 individuals were selected through stratified multistage random sampling from households living in different regions of Shiraz. Information on demographic characteristics, anthropometric features, dietary intakes, and systolic (SBP and diastolic (DBP blood pressure was gathered. Dietary patterns were determined using a validated food frequency questionnaire. Results: Three dietary patterns were specified: vegetable (high in vegetables and legumes, Western-like (high in meat, sugarsweetened beverages, salty and sweet snacks, refined grains, high-fat dairy, and Mediterranean-like (rich in low-fat dairy, fruit, vegetables, nuts, olive, fish, and low in hydrogenated fats. After adjustment for confounders, Mediterranean-like dietary pattern had an inverse association with SBP (β=-0.24; 95% CI: -5.25, -1.27 and DBP (β=-0.17; 95% CI: -3.65, -0.20 in males but not females. Vegetable and Western-like dietary patterns were not associated with BP in either sex after adjusting for confounders. Positive relationships were observed between BP and body mass index (r=0.28 and 0.33 for SBP and DBP, P<0.001, waist circumference (r=0.51 and 0.45 for SBP and DBP, P<0.001, and waist-to-hip ratio (r=0.54 and 0.44 for SBP and DBP, P<0.001. Dietary energy and carbohydrates were positively and fats inversely associated with BP. Among micronutrients, vitamin E had a significant inverse association with BP. Conclusion: Mediterranean-like dietary pattern may lower the risk of hypertension in Shiraz males.

Non-conventional procedure of polarimetry data inversion in conditions of comparable Faraday and Cotton-Mouton effects

International Nuclear Information System (INIS)

Kravtsov, Yu.A.; Chrzanowski, J.; Mazon, D.

2011-01-01

A new procedure for inverting plasma polarimetry data is proposed in this paper. The procedure is based on the fit between a two parameter knowledge-based plasma model, which is using both magnetic and Thompson scattering data, and the polarimetric measurements. In turn the polarimetry system is assumed to measure two angular parameters of polarization: its azimuthal and ellipticity angles. The inversion procedure under consideration is based on the angular variables technique (AVT), describing evolution of the angular parameters of polarization ellipse in weakly anisotropic plasma. Generally inversion procedure can be applied both for weak and significant Faraday and Cotton-Mouton effects. For weak polarimetric effects inversion procedure shows the results of traditional polarimetry.

Mercury in Hair Is Inversely Related to Disease Associated Damage in Systemic Lupus Erythematosus

Directory of Open Access Journals (Sweden)

William Crowe

2015-12-01

Full Text Available Systemic lupus erythematosus (SLE is an autoimmune inflammatory disease, and environmental factors are proposed to exacerbate existing symptoms. One such environmental factor is mercury. The aim of this study was to investigate the relationship between exposure to mercury (Hg and disease activity and disease associated damage in Total Hg concentrations in hair and urine were measured in 52 SLE patients. Dental amalgams were quantified. Disease activity was assessed using three indexes including the British Isles Lupus Assessment Group Index (BILAG. Disease associated damage was measured using the Systemic Lupus International Collaborating Clinics/American College of Rheumatology SLICC/ACR Damage Index. Pearson’s correlation identified a significant negative correlation between hair Hg and BILAG (r = −0.323, p = 0.029 and SLICC/ACR (r = −0.377, p = 0.038. Multiple regression analysis identified hair Hg as a significant predictor of disease associated damage as determined by SLICC/ACR (β = −0.366, 95% confidence interval (CI: −1.769, −0.155 p = 0.019. Urinary Hg was not related to disease activity or damage. Fish consumption is the primary route of MeHg exposure in humans and the inverse association of hair Hg with disease activity observed here might be explained by the anti-inflammatory effects of n-3 long chain polyunsaturated fatty acids also found in fish.

Semiautomatic and Automatic Cooperative Inversion of Seismic and Magnetotelluric Data

Science.gov (United States)

Le, Cuong V. A.; Harris, Brett D.; Pethick, Andrew M.; Takam Takougang, Eric M.; Howe, Brendan

2016-09-01

Natural source electromagnetic methods have the potential to recover rock property distributions from the surface to great depths. Unfortunately, results in complex 3D geo-electrical settings can be disappointing, especially where significant near-surface conductivity variations exist. In such settings, unconstrained inversion of magnetotelluric data is inexorably non-unique. We believe that: (1) correctly introduced information from seismic reflection can substantially improve MT inversion, (2) a cooperative inversion approach can be automated, and (3) massively parallel computing can make such a process viable. Nine inversion strategies including baseline unconstrained inversion and new automated/semiautomated cooperative inversion approaches are applied to industry-scale co-located 3D seismic and magnetotelluric data sets. These data sets were acquired in one of the Carlin gold deposit districts in north-central Nevada, USA. In our approach, seismic information feeds directly into the creation of sets of prior conductivity model and covariance coefficient distributions. We demonstrate how statistical analysis of the distribution of selected seismic attributes can be used to automatically extract subvolumes that form the framework for prior model 3D conductivity distribution. Our cooperative inversion strategies result in detailed subsurface conductivity distributions that are consistent with seismic, electrical logs and geochemical analysis of cores. Such 3D conductivity distributions would be expected to provide clues to 3D velocity structures that could feed back into full seismic inversion for an iterative practical and truly cooperative inversion process. We anticipate that, with the aid of parallel computing, cooperative inversion of seismic and magnetotelluric data can be fully automated, and we hold confidence that significant and practical advances in this direction have been accomplished.

A Joint Method of Envelope Inversion Combined with Hybrid-domain Full Waveform Inversion

Science.gov (United States)

CUI, C.; Hou, W.

2017-12-01

Full waveform inversion (FWI) aims to construct high-precision subsurface models by fully using the information in seismic records, including amplitude, travel time, phase and so on. However, high non-linearity and the absence of low frequency information in seismic data lead to the well-known cycle skipping problem and make inversion easily fall into local minima. In addition, those 3D inversion methods that are based on acoustic approximation ignore the elastic effects in real seismic field, and make inversion harder. As a result, the accuracy of final inversion results highly relies on the quality of initial model. In order to improve stability and quality of inversion results, multi-scale inversion that reconstructs subsurface model from low to high frequency are applied. But, the absence of very low frequencies (time domain and inversion in the frequency domain. To accelerate the inversion, we adopt CPU/GPU heterogeneous computing techniques. There were two levels of parallelism. In the first level, the inversion tasks are decomposed and assigned to each computation node by shot number. In the second level, GPU multithreaded programming is used for the computation tasks in each node, including forward modeling, envelope extraction, DFT (discrete Fourier transform) calculation and gradients calculation. Numerical tests demonstrated that the combined envelope inversion + hybrid-domain FWI could obtain much faithful and accurate result than conventional hybrid-domain FWI. The CPU/GPU heterogeneous parallel computation could improve the performance speed.

Ureaplasma urealyticum is significantly associated with non-gonococcal urethritis in heterosexual Sydney men.

Science.gov (United States)

Couldwell, D L; Gidding, H F; Freedman, E V; McKechnie, M L; Biggs, K; Sintchenko, V; Gilbert, G L

2010-05-01

We investigated the prevalence of various genital organisms in 268 men with (cases) and 237 men without (controls) urethral symptoms/signs (urethral discharge, dysuria and/or urethral irritation) from two sexual health clinics in Sydney between April 2006 and November 2007. The presence of urethral symptoms/signs was defined as non-gonococcal urethritis (NGU) for this study. Specific aims were to investigate the role of Ureaplasma urealyticum in NGU and the prevalence of Mycoplasma genitalium in our population. Multiplex polymerase chain reaction-based reverse line blot (mPCR/RLB) assay was performed to detect 14 recognized or putative genital pathogens, including Chlamydia trachomatis, M. genitalium, U. urealyticum and U. parvum. U. urealyticum was associated with NGU in men without another urethral pathogen (odds ratio [OR] 2.0, 95% confidence interval [CI] 1.1-3.8; P = 0.04); this association remained after controlling for potential confounding by age and history of unprotected vaginal sex in the last four weeks (OR 2.0, 95% CI: 1.1-3.9; P = 0.03). C. trachomatis (OR 7.5, P urethral pathogens. Further research should investigate the role of U. urealyticum subtypes among heterosexual men with NGU.

Inverse association between serum bilirubin levels and arterial stiffness in Korean women with type 2 diabetes.

Directory of Open Access Journals (Sweden)

Eun Sook Kim

Full Text Available BACKGROUND: Considerable evidence suggests that bilirubin is a potent physiologic antioxidant that may provide important protection against cardiovascular disease (CVD and inflammation. We investigated the relationship between serum total bilirubin (TB levels and arterial stiffness, measured by the brachial-ankle pulse wave velocity (baPWV, in patients with type 2 diabetes. METHODS: We conducted a cross-sectional analysis of 1,711 subjects with type 2 diabetes (807 men and 904 women; mean age, 57.1 years. The subjects were stratified based on gender-specific tertiles of TB values, and a high baPWV was defined as greater than 1,745 cm/s ( >75th percentile. RESULTS: The serum TB concentration was negatively correlated with the duration of diabetes, HbA1c, the 10-year Framingham risk score, and baPWV and was positively correlated with high-density lipoprotein cholesterol and the eGFR in both genders. Inverse association between TB categories and unadjusted prevalence of high PWV was only observed in women. After adjusting for confounding factors, the TB levels were inversely associated with a greater risk of a high baPWV, both as a continuous variable [a 1-SD difference; odds ratio (OR, 0.70; 95% confidence interval (CI, 0.54-0.90; P = 0.005] and when categorized in tertiles (the highest vs. the lowest tertile; OR, 0.49; 95% CI, 0.28-0.85; P = 0.011 in women but not in men. The relationship remained significant even after adjusting for retinopathy and nephropathy. CONCLUSIONS: Low TB levels were significantly associated with arterial stiffness in Korean women with type 2 diabetes. Our data suggested that bilirubin may protect against macrovascular disease in diabetic women.

Angelman syndrome associated with an inversion of chromosome 15q11.2q24.3

Energy Technology Data Exchange (ETDEWEB)

Greger, V.; Knoll, J.H.M.; Wagstaff, J.; Lalande, M. [and others

1997-03-01

Angelman syndrome (AS) most frequently results from large ({ge}5 Mb) de novo deletions of chromosome 15q11-q13. The deletions are exclusively of maternal origin, and a few cases of paternal uniparental disomy of chromosome 15 have been reported. The latter finding indicates that AS is caused by the absence of a maternal contribution to the imprinted 15q11-q13 region. Failure to inherit a paternal 15q11-q13 contribution results in the clinically distinct disorder of Prader-Willi syndrome. Cases of AS resulting from translocations or pericentric inversions have been observed to be associated with deletions, and there have been no confirmed reports of balanced rearrangements in AS. We report the first such case involving a paracentric inversion with a breakpoint located {approximately}25 kb proximal to the reference marker D15S10. This inversion has been inherited from a phenotypically normal mother. No deletion is evident by molecular analysis in this case, by use of cloned fragments mapped to within {approximately}1 kb of the inversion breakpoint. Several hypotheses are discussed to explain the relationship between the inversion and the AS phenotype. 47 refs., 3 figs.

Anisotropic three-dimensional inversion of CSEM data using finite-element techniques on unstructured grids

Science.gov (United States)

Wang, Feiyan; Morten, Jan Petter; Spitzer, Klaus

2018-05-01

In this paper, we present a recently developed anisotropic 3-D inversion framework for interpreting controlled-source electromagnetic (CSEM) data in the frequency domain. The framework integrates a high-order finite-element forward operator and a Gauss-Newton inversion algorithm. Conductivity constraints are applied using a parameter transformation. We discretize the continuous forward and inverse problems on unstructured grids for a flexible treatment of arbitrarily complex geometries. Moreover, an unstructured mesh is more desirable in comparison to a single rectilinear mesh for multisource problems because local grid refinement will not significantly influence the mesh density outside the region of interest. The non-uniform spatial discretization facilitates parametrization of the inversion domain at a suitable scale. For a rapid simulation of multisource EM data, we opt to use a parallel direct solver. We further accelerate the inversion process by decomposing the entire data set into subsets with respect to frequencies (and transmitters if memory requirement is affordable). The computational tasks associated with each data subset are distributed to different processes and run in parallel. We validate the scheme using a synthetic marine CSEM model with rough bathymetry, and finally, apply it to an industrial-size 3-D data set from the Troll field oil province in the North Sea acquired in 2008 to examine its robustness and practical applicability.

Free Triiodothyronine Concentrations Are Inversely Associated with Microalbuminuria

Directory of Open Access Journals (Sweden)

Yulin Zhou

2014-01-01

Full Text Available Thyroid function and microalbuminuria are both associated with vascular disease and endothelial damage. However, whether thyroid function is associated with microalbuminuria is not well established. The objective was to explore the relationship between thyroid hormones and microalbuminuria in Chinese population. A community-based cross-sectional study was performed among 3,346 Chinese adults (aged ≥ 40 years. Serum free triiodothyronine (FT3, free thyroxine (FT4, and TSH (thyroid stimulating hormone were determined by chemiluminescent microparticle immunoassay. A single-void first morning urine sample was obtained for urinary albumin-creatinine ratio measurement. The prevalence of microalbuminuria decreased according to FT3 quartiles (13.2, 9.5, 8.6, and 8.2%, P for trend = 0.0005. A fully adjusted logistic regression analysis showed that high FT3 levels were associated with low prevalent microalbuminuria. The adjusted odds ratios for microalbuminuria were 0.61 (95% CI, 0.43–0.87, P = 0.007 when comparing the highest with the lowest quartile of FT3. The exclusion of participants with abnormal FT3 did not appreciably change the results (OR = 0.69, 95% CI, 0.49–0.98, P = 0.02. We concluded that serum FT3 levels, even within the normal range, were inversely associated with microalbuminuria in middle-aged and elderly Chinese adults. FT3 concentrations might play a role in the pathogenesis of microalbuminuria.

Allergic Contact Dermatitis Is Associated with Significant Oxidative Stress

Directory of Open Access Journals (Sweden)

S. Kaur

2014-01-01

Full Text Available Background. Research has confirmed the involvement of oxidative stress (OxS in allergic contact dermatitis whilst other inflammation-related biomarkers have been less studied. Objective. To evaluate systemic levels of selected inflammatory markers, OxS indices and adipokines as well as their associations in allergic contact dermatitis. Methods. In 40 patients, interleukin- (IL- 6, monocyte chemoattractant protein (MCP-1, and IL-10 levels were measured in sera with the Evidence Investigator Cytokine & Growth factors High-Sensitivity Array, total peroxide concentration (TPX and total antioxidant capacity (TAC by means of spectrophotometry, and the plasma concentrations of adiponectin and leptin by the quantitative sandwich enzyme immunoassay technique. Results. TNF-α level (P < 0.01 and TPX (P < 0.0001 were increased whilst IL-10 (P < 0.05 and TAC (P < 0.0001 were decreased in the patients as compared to controls. Correlation and multiple linear regression analysis identified both, TPX and TAC (inversely, as possible independent markers for evaluating allergic contact dermatitis. Adiponectin level in patients was increased (P < 0.0001, but neither adiponectin nor leptin correlated significantly with the biomarkers of inflammation or OxS. Conclusion. OxS parameters, especially TPX and OSI, reflect the degree of systemic inflammation associated with allergic contact dermatitis in the best way. The relation between OxS and adiponectin level warrants further studies.

MARE2DEM: a 2-D inversion code for controlled-source electromagnetic and magnetotelluric data

Science.gov (United States)

Key, Kerry

2016-10-01

This work presents MARE2DEM, a freely available code for 2-D anisotropic inversion of magnetotelluric (MT) data and frequency-domain controlled-source electromagnetic (CSEM) data from onshore and offshore surveys. MARE2DEM parametrizes the inverse model using a grid of arbitrarily shaped polygons, where unstructured triangular or quadrilateral grids are typically used due to their ease of construction. Unstructured grids provide significantly more geometric flexibility and parameter efficiency than the structured rectangular grids commonly used by most other inversion codes. Transmitter and receiver components located on topographic slopes can be tilted parallel to the boundary so that the simulated electromagnetic fields accurately reproduce the real survey geometry. The forward solution is implemented with a goal-oriented adaptive finite-element method that automatically generates and refines unstructured triangular element grids that conform to the inversion parameter grid, ensuring accurate responses as the model conductivity changes. This dual-grid approach is significantly more efficient than the conventional use of a single grid for both the forward and inverse meshes since the more detailed finite-element meshes required for accurate responses do not increase the memory requirements of the inverse problem. Forward solutions are computed in parallel with a highly efficient scaling by partitioning the data into smaller independent modeling tasks consisting of subsets of the input frequencies, transmitters and receivers. Non-linear inversion is carried out with a new Occam inversion approach that requires fewer forward calls. Dense matrix operations are optimized for memory and parallel scalability using the ScaLAPACK parallel library. Free parameters can be bounded using a new non-linear transformation that leaves the transformed parameters nearly the same as the original parameters within the bounds, thereby reducing non-linear smoothing effects. Data

Angle-domain inverse scattering migration/inversion in isotropic media

Science.gov (United States)

Li, Wuqun; Mao, Weijian; Li, Xuelei; Ouyang, Wei; Liang, Quan

2018-07-01

The classical seismic asymptotic inversion can be transformed into a problem of inversion of generalized Radon transform (GRT). In such methods, the combined parameters are linearly attached to the scattered wave-field by Born approximation and recovered by applying an inverse GRT operator to the scattered wave-field data. Typical GRT-style true-amplitude inversion procedure contains an amplitude compensation process after the weighted migration via dividing an illumination associated matrix whose elements are integrals of scattering angles. It is intuitional to some extent that performs the generalized linear inversion and the inversion of GRT together by this process for direct inversion. However, it is imprecise to carry out such operation when the illumination at the image point is limited, which easily leads to the inaccuracy and instability of the matrix. This paper formulates the GRT true-amplitude inversion framework in an angle-domain version, which naturally degrades the external integral term related to the illumination in the conventional case. We solve the linearized integral equation for combined parameters of different fixed scattering angle values. With this step, we obtain high-quality angle-domain common-image gathers (CIGs) in the migration loop which provide correct amplitude-versus-angle (AVA) behavior and reasonable illumination range for subsurface image points. Then we deal with the over-determined problem to solve each parameter in the combination by a standard optimization operation. The angle-domain GRT inversion method keeps away from calculating the inaccurate and unstable illumination matrix. Compared with the conventional method, the angle-domain method can obtain more accurate amplitude information and wider amplitude-preserved range. Several model tests demonstrate the effectiveness and practicability.

The origin, global distribution, and functional impact of the human 8p23 inversion polymorphism.

Science.gov (United States)

Salm, Maximilian P A; Horswell, Stuart D; Hutchison, Claire E; Speedy, Helen E; Yang, Xia; Liang, Liming; Schadt, Eric E; Cookson, William O; Wierzbicki, Anthony S; Naoumova, Rossi P; Shoulders, Carol C

2012-06-01

Genomic inversions are an increasingly recognized source of genetic variation. However, a lack of reliable high-throughput genotyping assays for these structures has precluded a full understanding of an inversion's phylogenetic, phenotypic, and population genetic properties. We characterize these properties for one of the largest polymorphic inversions in man (the ∼4.5-Mb 8p23.1 inversion), a structure that encompasses numerous signals of natural selection and disease association. We developed and validated a flexible bioinformatics tool that utilizes SNP data to enable accurate, high-throughput genotyping of the 8p23.1 inversion. This tool was applied retrospectively to diverse genome-wide data sets, revealing significant population stratification that largely follows a clinal "serial founder effect" distribution model. Phylogenetic analyses establish the inversion's ancestral origin within the Homo lineage, indicating that 8p23.1 inversion has occurred independently in the Pan lineage. The human inversion breakpoint was localized to an inverted pair of human endogenous retrovirus elements within the large, flanking low-copy repeats; experimental validation of this breakpoint confirmed these elements as the likely intermediary substrates that sponsored inversion formation. In five data sets, mRNA levels of disease-associated genes were robustly associated with inversion genotype. Moreover, a haplotype associated with systemic lupus erythematosus was restricted to the derived inversion state. We conclude that the 8p23.1 inversion is an evolutionarily dynamic structure that can now be accommodated into the understanding of human genetic and phenotypic diversity.

Significance of deep T-wave inversions in asymptomatic athletes with normal cardiovascular examinations: practical solutions for managing the diagnostic conundrum.

Science.gov (United States)

Wilson, M G; Sharma, S; Carré, F; Charron, P; Richard, P; O'Hanlon, R; Prasad, S K; Heidbuchel, H; Brugada, J; Salah, O; Sheppard, M; George, K P; Whyte, G; Hamilton, B; Chalabi, H

2012-11-01

Preparticipation screening programmes for underlying cardiac pathologies are now commonplace for many international sporting organisations. However, providing medical clearance for an asymptomatic athlete without a family history of sudden cardiac death (SCD) is especially challenging when the athlete demonstrates particularly abnormal repolarisation patterns, highly suggestive of an inherited cardiomyopathy or channelopathy. Deep T-wave inversions of ≥ 2 contiguous anterior or lateral leads (but not aVR, and III) are of major concern for sports cardiologists who advise referring team physicians, as these ECG alterations are a recognised manifestation of hypertrophic cardiomyopathy (HCM) and arrhythmogenic right ventricular cardiomyopathy (ARVC). Subsequently, inverted T-waves may represent the first and only sign of an inherited heart muscle disease, in the absence of any other features and before structural changes in the heart can be detected. However, to date, there remains little evidence that deep T-wave inversions are always pathognomonic of either a cardiomyopathy or an ion channel disorder in an asymptomatic athlete following long-term follow-up. This paper aims to provide a systematic review of the prevalence of T-wave inversion in athletes and examine T-wave inversion and its relationship to structural heart disease, notably HCM and ARVC with a view to identify young athletes at risk of SCD during sport. Finally, the review proposes clinical management pathways (including genetic testing) for asymptomatic athletes demonstrating significant T-wave inversion with structurally normal hearts.

Association of Blood and Seminal Plasma Cadmium and Lead Levels With Semen Quality in Non-Occupationally Exposed Infertile Men in Abakaliki, South East Nigeria

Directory of Open Access Journals (Sweden)

Ademola C Famurewa

2017-10-01

Full Text Available Objective: To evaluate association of blood and seminal plasma lead and cadmium with sperm quality of non-occupationally exposed male partners of couples with infertility.Materials and methods: A cross-sectional study was conducted on 75 men aged 20-45 years (mean = 37.1 ± 7.0 yrs. with infertility recruited from the Fertility Clinic of a hospital in Abakaliki. Sperm count done in accordance with the WHO guidelines was used to classify the participants as normospamia, oligospermia and azospermia. Atomic absorption spectrophotometer was used to determine lead and cadmium levels in plasma from blood and semen.Results: There were 15 azospermics, 22 oligospermics and 36 normospermics. Seminal and blood plasma cadmium as well as blood plasma lead were significantly (p < 0.01 higher in azospermic and oligospermic men compared to normospermic men. However, while seminal plasma lead was significantly (p < 0.05 higher in oligospermic and normospernic men than in azospermic men, the seminal plasma lead was comparable between oligospermic and normospermic men. Significant inverse associations (p < 0.01 were found between blood and seminal cadmium levels and sperm count, motility and morphology; blood lead was inversely correlated with sperm count only.Conclusion: The study suggests that environmental exposure to cadmium and lead may contribute to development of poor sperm quality and infertility in men of reproductive age in Nigeria.

Relative sensitivity of depth discrimination for ankle inversion and plantar flexion movements.

Science.gov (United States)

Black, Georgia; Waddington, Gordon; Adams, Roger

2014-02-01

25 participants (20 women, 5 men) were tested for sensitivity in discrimination between sets of six movements centered on 8 degrees, 11 degrees, and 14 degrees, and separated by 0.3 degrees. Both inversion and plantar flexion movements were tested. Discrimination of the extent of inversion movement was observed to decline linearly with increasing depth; however, for plantar flexion, the discrimination function for movement extent was found to be non-linear. The relatively better discrimination of plantar flexion movements than inversion movements at around 11 degrees from horizontal is interpreted as an effect arising from differential amounts of practice through use, because this position is associated with the plantar flexion movement made in normal walking. The fact that plantar flexion movements are discriminated better than inversion at one region but not others argues against accounts of superior proprioceptive sensitivity for plantar flexion compared to inversion that are based on general properties of plantar flexion such as the number of muscle fibres on stretch.

Time-domain incomplete Gauss-Newton full-waveform inversion of Gulf of Mexico data

KAUST Repository

AlTheyab, Abdullah

2013-09-22

We apply the incomplete Gauss-Newton full-waveform inversion (TDIGN-FWI) to Gulf of Mexico (GOM) data in the space-time domain. In our application, iterative least-squares reverse-time migration (LSRTM) is used to estimate the model update at each non-linear iteration, and the number of LSRTM iterations is progressively increased after each non-linear iteration. With this method, model updating along deep reflection wavepaths are automatically enhanced, which in turn improves imaging below the reach of diving-waves. The forward and adjoint operators are implemented in the space-time domain to simultaneously invert the data over a range of frequencies. A multiscale approach is used where higher frequencies are down-weighted significantly at early iterations, and gradually included in the inversion. Synthetic data results demonstrate the effectiveness of reconstructing both the high- and low-wavenumber features in the model without relying on diving waves in the inversion. Results with Gulf of Mexico field data show a significantly improved migration image in both the shallow and deep sections.

Inverse kinematic-based robot control

Science.gov (United States)

Wolovich, W. A.; Flueckiger, K. F.

1987-01-01

A fundamental problem which must be resolved in virtually all non-trivial robotic operations is the well-known inverse kinematic question. More specifically, most of the tasks which robots are called upon to perform are specified in Cartesian (x,y,z) space, such as simple tracking along one or more straight line paths or following a specified surfacer with compliant force sensors and/or visual feedback. In all cases, control is actually implemented through coordinated motion of the various links which comprise the manipulator; i.e., in link space. As a consequence, the control computer of every sophisticated anthropomorphic robot must contain provisions for solving the inverse kinematic problem which, in the case of simple, non-redundant position control, involves the determination of the first three link angles, theta sub 1, theta sub 2, and theta sub 3, which produce a desired wrist origin position P sub xw, P sub yw, and P sub zw at the end of link 3 relative to some fixed base frame. Researchers outline a new inverse kinematic solution and demonstrate its potential via some recent computer simulations. They also compare it to current inverse kinematic methods and outline some of the remaining problems which will be addressed in order to render it fully operational. Also discussed are a number of practical consequences of this technique beyond its obvious use in solving the inverse kinematic question.

Non-Random Inversion Landscapes in Prokaryotic Genomes Are Shaped by Heterogeneous Selection Pressures.

Science.gov (United States)

Repar, Jelena; Warnecke, Tobias

2017-08-01

Inversions are a major contributor to structural genome evolution in prokaryotes. Here, using a novel alignment-based method, we systematically compare 1,651 bacterial and 98 archaeal genomes to show that inversion landscapes are frequently biased toward (symmetric) inversions around the origin-terminus axis. However, symmetric inversion bias is not a universal feature of prokaryotic genome evolution but varies considerably across clades. At the extremes, inversion landscapes in Bacillus-Clostridium and Actinobacteria are dominated by symmetric inversions, while there is little or no systematic bias favoring symmetric rearrangements in archaea with a single origin of replication. Within clades, we find strong but clade-specific relationships between symmetric inversion bias and different features of adaptive genome architecture, including the distance of essential genes to the origin of replication and the preferential localization of genes on the leading strand. We suggest that heterogeneous selection pressures have converged to produce similar patterns of structural genome evolution across prokaryotes. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

Reverse Universal Resolving Algorithm and inverse driving

DEFF Research Database (Denmark)

Pécseli, Thomas

2012-01-01

Inverse interpretation is a semantics based, non-standard interpretation of programs. Given a program and a value, an inverse interpreter finds all or one of the inputs, that would yield the given value as output with normal forward evaluation. The Reverse Universal Resolving Algorithm is a new...... variant of the Universal Resolving Algorithm for inverse interpretation. The new variant outperforms the original algorithm in several cases, e.g., when unpacking a list using inverse interpretation of a pack program. It uses inverse driving as its main technique, which has not been described in detail...... before. Inverse driving may find application with, e.g., supercompilation, thus suggesting a new kind of program inverter....

Macroporous Inverse Opal-like MoxC with Incorporated Mo Vacancies for Significantly Enhanced Hydrogen Evolution.

Science.gov (United States)

Li, Feng; Zhao, Xianglong; Mahmood, Javeed; Okyay, Mahmut Sait; Jung, Sun-Min; Ahmad, Ishfaq; Kim, Seok-Jin; Han, Gao-Feng; Park, Noejung; Baek, Jong-Beom

2017-07-25

The hydrogen evolution reaction (HER) is one of the most important pathways for producing pure and clean hydrogen. Although platinum (Pt) is the most efficient HER electrocatalyst, its practical application is significantly hindered by high-cost and scarcity. In this work, an Mo x C with incorporated Mo vacancies and macroporous inverse opal-like (IOL) structure (Mo x C-IOL) was synthesized and studied as a low-cost efficient HER electrocatalyst. The macroporous IOL structure was controllably fabricated using a facile-hard template strategy. As a result of the combined benefits of the Mo vacancies and structural advantages, including appropriate hydrogen binding energy, large exposed surface, robust IOL structure and fast mass/charge transport, the synthesized Mo x C-IOL exhibited significantly enhanced HER electrocatalytic performance with good stability, with performance comparable or superior to Pt wire in both acidic and alkaline solutions.

Inverse consistent non-rigid image registration based on robust point set matching

Science.gov (United States)

2014-01-01

Background Robust point matching (RPM) has been extensively used in non-rigid registration of images to robustly register two sets of image points. However, except for the location at control points, RPM cannot estimate the consistent correspondence between two images because RPM is a unidirectional image matching approach. Therefore, it is an important issue to make an improvement in image registration based on RPM. Methods In our work, a consistent image registration approach based on the point sets matching is proposed to incorporate the property of inverse consistency and improve registration accuracy. Instead of only estimating the forward transformation between the source point sets and the target point sets in state-of-the-art RPM algorithms, the forward and backward transformations between two point sets are estimated concurrently in our algorithm. The inverse consistency constraints are introduced to the cost function of RPM and the fuzzy correspondences between two point sets are estimated based on both the forward and backward transformations simultaneously. A modified consistent landmark thin-plate spline registration is discussed in detail to find the forward and backward transformations during the optimization of RPM. The similarity of image content is also incorporated into point matching in order to improve image matching. Results Synthetic data sets, medical images are employed to demonstrate and validate the performance of our approach. The inverse consistent errors of our algorithm are smaller than RPM. Especially, the topology of transformations is preserved well for our algorithm for the large deformation between point sets. Moreover, the distance errors of our algorithm are similar to that of RPM, and they maintain a downward trend as whole, which demonstrates the convergence of our algorithm. The registration errors for image registrations are evaluated also. Again, our algorithm achieves the lower registration errors in same iteration number

Acute puerperal uterine inversion

International Nuclear Information System (INIS)

Hussain, M.; Liaquat, N.; Noorani, K.; Bhutta, S.Z; Jabeen, T.

2004-01-01

Objective: To determine the frequency, causes, clinical presentations, management and maternal mortality associated with acute puerperal inversion of the uterus. Materials and Methods: All the patients who developed acute puerperal inversion of the uterus either in or outside the JPMC were included in the study. Patients of chronic uterine inversion were not included in the present study. Abdominal and vaginal examination was done to confirm and classify inversion into first, second or third degrees. Results: 57036 deliveries and 36 acute uterine inversions occurred during the study period, so the frequency of uterine inversion was 1 in 1584 deliveries. Mismanagement of third stage of labour was responsible for uterine inversion in 75% of patients. Majority of the patients presented with shock, either hypovolemic (69%) or neurogenic (13%) in origin. Manual replacement of the uterus under general anaesthesia with 2% halothane was successfully done in 35 patients (97.5%). Abdominal hysterectomy was done in only one patient. There were three maternal deaths due to inversion. Conclusion: Proper education and training regarding placental delivery, diagnosis and management of uterine inversion must be imparted to the maternity care providers especially to traditional birth attendants and family physicians to prevent this potentially life-threatening condition. (author)

Significant decrease of saturation index in erythrocytes membrane from subjects with non-alcoholic fatty liver disease (NAFLD).

Science.gov (United States)

Notarnicola, Maria; Caruso, Maria Gabriella; Tutino, Valeria; Bonfiglio, Caterina; Cozzolongo, Raffaele; Giannuzzi, Vito; De Nunzio, Valentina; De Leonardis, Giampiero; Abbrescia, Daniela I; Franco, Isabella; Intini, Vincenza; Mirizzi, Antonella; Osella, Alberto R

2017-08-23

The lipidomic profiling of erythrocyte membranes is expected to provide a peculiar scenario at molecular level of metabolic and nutritional pathways which may influence the lipid balance and the adaptation and homeostasis of the organism. Considering that lipid accumulation in the cell is important in promoting tissue inflammation, the purpose of this study is to analyze the fatty acid profile in red blood cell membranes of patients with Non-Alcoholic Fatty Liver Disease (NAFLD), in order to identify and validate membrane profiles possibly associated with the degree of hepatic damage. This work presents data obtained at baseline from 101 subjects that participated to a nutritional trial (registration number: NCT02347696) enrolling consecutive subjects with NAFLD. Diagnosis of liver steatosis was performed by using vibration-controlled elastography implemented on FibroScan. Fatty acids, extracted from phospholipids of erythrocyte membranes, were quantified by gas chromatography method. The subjects with severe NAFLD showed a significant decrease of the ratio of stearic acid to oleic acid (saturation index, SI) compared to controls, 1.281 ± 0.31 vs 1.5 ± 0.29, respectively. Low levels of SI in red blood cell membranes, inversely associated with degree of liver damage, suggest that an impairment of circulating cell membrane structure can reflect modifications that take place in the liver. Subjects with severe NAFLDalso showed higher levels of elongase 5 enzymatic activity, evaluated as vaccenic acid to palmitoleic acid ratio. Starting from these evidences, our findings show the importance of lipidomic approach in the diagnosis and the staging of NAFLD.

Sex, Adiposity, and Hypertension Status Modify the Inverse Effect of Marine Food Intake on Blood Pressure in Alaska Native (Yup'ik) People.

Science.gov (United States)

Beaulieu-Jones, Brendin R; O'Brien, Diane M; Hopkins, Scarlett E; Moore, Jason H; Boyer, Bert B; Gilbert-Diamond, Diane

2015-05-01

Alaska Native people currently have a higher prevalence of hypertension than do nonnative Alaskans, although in the 1950s hypertension was rare among Alaska Native people. A novel biomarker of marine foods, the nitrogen isotope ratio (δ¹⁵N) in RBCs was shown to be negatively associated with systolic and diastolic blood pressure. Few studies have examined how individual characteristics modify the association of marine food intake with blood pressure. This exploratory analysis examined whether sex, adiposity, and hypertension modify the inverse association between marine food intake and blood pressure. We used covariate-adjusted linear models to describe the association between δ¹⁵N and blood pressure in 873 adult Alaska Native (Yup'ik) people who resided in 8 communities in southwest Alaska. We separately stratified by sex, body mass index (BMI) group, abdominal obesity, and hypertension status and assessed the interaction between δ¹⁵N and participant characteristics on blood pressure via likelihood ratio tests. The association between δ¹⁵N and systolic blood pressure was modified by sex, BMI status, and abdominal obesity, with the inverse association observed only in the male (β = -1.5; 95% CI: -2.4, -0.6 : , nonobese BMI (β = -1.7; 95% CI: -2.5, -1.0), and non-abdominally obese (β = -1.6; 95% CI: -2.4, -0.9) strata (all P-interaction blood pressure associated with δ¹⁵N was observed in the nonobese BMI (β = -1.1; 95% CI: -1.7, -0.5) and non-abdominally obese (β = -1.1; 95% CI: -1.7, -0.5) strata, although only the interaction between BMI group and δ¹⁵N with diastolic blood pressure was significant. The inverse association between δ¹⁵N and both systolic and diastolic blood pressure was observed in nonhypertensive individuals, although the comparison had limited power. The results were consistent with those identified by using combined RBC concentrations of eicosapentaenoic acid and docosahexaenoic acid as the biomarker of marine food

Inversion (X)(p11.4q22) associated with Norrie disease in a four generation family.

Science.gov (United States)

Pettenati, M J; Rao, P N; Weaver, R G; Thomas, I T; McMahan, M R

1993-03-01

We report on a 4-generation family in which Norrie disease occurs together with a pericentric inversion of the X chromosome in all affected males and carrier females. The breakpoint in the short arm of the X chromosome appears to be at the purported location of the Norrie disease gene. This is the second report of an association between Norrie disease and a chromosome aberration involving Xp11, and the first report of a specific gene disruption, thus physical gene location, due to a pericentric chromosome inversion.

Diet quality is inversely associated with C-reactive protein levels in urban, low-income African-American and white adults.

Science.gov (United States)

Kuczmarski, Marie Fanelli; Mason, Marc A; Allegro, Deanne; Zonderman, Alan B; Evans, Michele K

2013-12-01

C-reactive protein (CRP), an inflammatory biomarker, is influenced by many factors, including socioeconomic position, genetics, and diet. The inverse association between diet and CRP is biologically feasible because micronutrients with antioxidative properties may enable the body to manage the balance between production and accumulation of reactive species that cause oxidative stress. To determine the quality of the diet consumed by urban, low-income African-American and white adults aged 30 to 64 years, and association of diet quality with CRP. Data from a cross-sectional study were used to evaluate diet quality assessed by mean adequacy ratio (MAR). Two 24-hour recalls were collected by trained interviewers using the US Department of Agriculture automated multiple pass method. The sample consisted of Healthy Aging in Neighborhoods of Diversity across the Life Span baseline study participants, 2004-2009, who completed both recalls (n=2,017). MAR equaled the average of the ratio of intakes to Recommended Dietary Allowance for 15 vitamins and minerals. CRP levels were assessed by the nephelometric method utilizing latex particles coated with CRP monoclonal antibodies. Linear ordinary least square regression and generalized linear models were performed to determine the association of MAR (independent variable) with CRP (dependent variable) while adjusting for potential confounders. MAR scores ranged from 74.3 to 82.2. Intakes of magnesium and vitamins A, C, and E were the most inadequate compared with Estimated Average Requirements. CRP levels were significantly associated with MAR, dual-energy x-ray absorptiometry-measured body fat, and hypertension. A 10% increase in MAR was associated with a 4% decrease in CRP. The MAR was independently and significantly inversely associated with CRP, suggesting diet is associated with the regulation of inflammation. Interventions to assist people make better food choices may not only improve diet quality but also their health

Association between menarche and iron deficiency in non-anemic young women.

Directory of Open Access Journals (Sweden)

Deepa L Sekhar

Full Text Available The prevalence of iron deficiency (ID among non-pregnant, reproductive-age US women significantly exceeds rates among males. In clinical practice ID screening relies on hemoglobin, a late-stage indicator of ID. As a single, low-cost laboratory test to diagnose ID before anemia develops is lacking, the study objective was to improve ID screening by identifying risk factors among non-anemic, iron-deficient reproductive age women.Cross-sectional data were from the National Health and Nutrition Examination Survey (NHANES 2003-2010. Hemoglobin identified non-anemic women. ID was defined using the body iron formula, requiring ferritin and transferrin receptor values. Logistic regression assessed the association of sociodemographic, behavioral, and reproductive risk factors in an anemia-based conceptual framework with non-anemic reproductive age women (12-49 years with ID, as well as subsets of younger (12-21 years and older (22-49 years women, recognizing that risks may differ by age.Among 6216 women, 494 had ID (prevalence was 8.0%, 95% CI 7.3%, 8.6%. Among non-anemic younger women, 250 (8.7%, 95% CI 7.7%, 9.8% had ID, compared to 244 (7.3%, 95% CI 6.4%, 8.2% older women. Among younger women, menstruation for over 3 years was the only variable significantly associated with non-anemic ID (risk ratio 3.18, 95% CI 2.03, 4.96. No other significant risk factors were identified.Menstrual years was the only risk factor significantly associated with ID among non-anemic younger women. The negative results suggest ID risk factors among non-anemic women may need to be considered separately from those associated with ID anemia.

Inverse problems in complex material design: Applications to non-crystalline solids

Science.gov (United States)

Biswas, Parthapratim; Drabold, David; Elliott, Stephen

The design of complex amorphous materials is one of the fundamental problems in disordered condensed-matter science. While impressive developments of ab-initio simulation methods during the past several decades have brought tremendous success in understanding materials property from micro- to mesoscopic length scales, a major drawback is that they fail to incorporate existing knowledge of the materials in simulation methodologies. Since an essential feature of materials design is the synergy between experiment and theory, a properly developed approach to design materials should be able to exploit all available knowledge of the materials from measured experimental data. In this talk, we will address the design of complex disordered materials as an inverse problem involving experimental data and available empirical information. We show that the problem can be posed as a multi-objective non-convex optimization program, which can be addressed using a number of recently-developed bio-inspired global optimization techniques. In particular, we will discuss how a population-based stochastic search procedure can be used to determine the structure of non-crystalline solids (e.g. a-SiH, a-SiO2, amorphous graphene, and Fe and Ni clusters). The work is partially supported by NSF under Grant Nos. DMR 1507166 and 1507670.

Inverse association between dietary vitamin D and risk of cutaneous melanoma in a northern Italy population

Science.gov (United States)

Vinceti, Marco; Malagoli, Carlotta; Fiorentini, Chiara; Longo, Caterina; Crespi, Catherine M.; Albertini, Giuseppe; Ricci, Cinzia; Lanzoni, Anna; Reggiani, Maurizio; Virgili, Annarosa; Osti, Federica; Lombardi, Mara; Santini, Marcello; Fanti, Pier Alessandro; Dika, Emi; Sieri, Sabina; Krogh, Vittorio; Seidenari, Stefania; Pellacani, Giovanni

2010-01-01

The possibility of an inverse association between vitamin D and risk of cancer and, in particular, of cutaneous malignant melanoma has been suggested, but results of epidemiologic studies are still conflicting. We examined the relation between dietary vitamin D intake and melanoma risk through a population-based case-control study (380 cases, 719 controls) in a northern region of Italy, a country with average vitamin D intake lower than in northern Europe or the US. We assessed average daily intake of vitamin D from foodstuffs using the European Prospective Investigation into Cancer and Nutrition (EPIC) semiquantitative food frequency questionnaire. In this population, levels of vitamin D intake were considerably lower than those observed in recent US studies. We found an inverse relation between dietary vitamin D and melanoma risk in the sample as a whole, in both crude and adjusted analyses. In sex and age-specific analyses, this association appeared to be stronger among males and among older subjects. These findings suggest that, at the relatively low levels of intake observed in this sample, an inverse relation between dietary vitamin D and risk of cutaneous malignant melanoma may exist. PMID:21541899

Jump-and-return sandwiches: A new family of binomial-like selective inversion sequences with improved performance

Science.gov (United States)

Brenner, Tom; Chen, Johnny; Stait-Gardner, Tim; Zheng, Gang; Matsukawa, Shingo; Price, William S.

2018-03-01

A new family of binomial-like inversion sequences, named jump-and-return sandwiches (JRS), has been developed by inserting a binomial-like sequence into a standard jump-and-return sequence, discovered through use of a stochastic Genetic Algorithm optimisation. Compared to currently used binomial-like inversion sequences (e.g., 3-9-19 and W5), the new sequences afford wider inversion bands and narrower non-inversion bands with an equal number of pulses. As an example, two jump-and-return sandwich 10-pulse sequences achieved 95% inversion at offsets corresponding to 9.4% and 10.3% of the non-inversion band spacing, compared to 14.7% for the binomial-like W5 inversion sequence, i.e., they afforded non-inversion bands about two thirds the width of the W5 non-inversion band.

Distribution and correlates of non-high-density lipoprotein cholesterol and triglycerides in Lebanese school children.

Science.gov (United States)

Gannagé-Yared, Marie-Hélène; Farah, Vanessa; Chahine, Elise; Balech, Nicole; Ibrahim, Toni; Asmar, Nadia; Barakett-Hamadé, Vanda; Jambart, Selim

2016-01-01

The prevalence of dyslipidelmia in pediatric Middle-Eastern populations is unknown. Our study aims to investigate the distribution and correlates of non-high-density lipoprotein cholesterol (non-HDL-C) and triglycerides among Lebanese school children. A total of 969 subjects aged 8-18 years were included in the study (505 boys and 464 girls). Recruitment was done from 10 schools located in the Great Beirut and Mount-Lebanon areas. Non-fasting total cholesterol, triglycerides, and HDL-cholesterol (HDL-C) were measured. Non-HDL-C was calculated. Schools were categorized into 3 socioeconomic statuses (SESs; low, middle, and high). In the overall population, the prevalence of high non-HDL-C (>3.8 mmol/L), very high non-HDL-C (>4.9 mmol/L), and high triglycerides (>1.5 mmol/l) are respectively 9.2%, 1.24%, and 26.6%. There is no significant gender difference for non-HDL-C or triglycerides. Non-HDL-C and triglycerides are inversely correlated with age in girls (P triglycerides are higher in children from lower SES schools. After adjustment for age and body mass index (BMI), testosterone is inversely associated with triglycerides in boys (P triglycerides are independently associated with BMI and schools' SES in both girls and boys. This study confirms, in our population, the association between obesity and both high non-HDL-C and triglycerides, and between high triglycerides and low SES. Copyright © 2016 National Lipid Association. Published by Elsevier Inc. All rights reserved.

Non-Puerperal Uterine Inversion Following a Prolapsed Leiomyoma ...

African Journals Online (AJOL)

Surgical repositioning can also be done through a laparotomy using the Huntington procedure, which consists in locating the cup of uterus formed by the inversion, dilating the cervical ring digitally, and gentle upward traction of the round ligaments of the uterus [6]. The. Haultaim procedure uses a vertical incision in the post.

FAST INVERSION OF SOLAR Ca II SPECTRA

International Nuclear Information System (INIS)

Beck, C.; Choudhary, D. P.; Rezaei, R.; Louis, R. E.

2015-01-01

We present a fast (<<1 s per profile) inversion code for solar Ca II lines. The code uses an archive of spectra that are synthesized prior to the inversion under the assumption of local thermodynamic equilibrium (LTE). We show that it can be successfully applied to spectrograph data or more sparsely sampled spectra from two-dimensional spectrometers. From a comparison to a non-LTE inversion of the same set of spectra, we derive a first-order non-LTE correction to the temperature stratifications derived in the LTE approach. The correction factor is close to unity up to log τ ∼ –3 and increases to values of 2.5 and 4 at log τ = –6 in the quiet Sun and the umbra, respectively

Associations between andrological measures, hormones and semen quality in fertile Australian men: inverse relationship between obesity and sperm output.

Science.gov (United States)

Stewart, T M; Liu, D Y; Garrett, C; Jørgensen, N; Brown, E H; Baker, H W G

2009-07-01

The World Health Organization developed a time to pregnancy (TTP) study (number of menstrual cycles taken to conceive) to determine whether the average TTP is increasing and semen quality decreasing with time. The present study describes clinical, semen and hormone characteristics obtained from male partners of pregnant women in Melbourne, Australia, and examines the associations between these characteristics. Male partners (n = 225) of pregnant women (16-32 weeks) who conceived naturally had physical examination, health and lifestyle questionnaires, semen and hormone (FSH, LH, sex hormone-binding globulin, testosterone and Inhibin B) analyses. Previously known associations between semen, hormone and clinical variables were confirmed as significant: sperm numbers (concentration and total sperm count) correlated positively with Inhibin B and inversely with FSH and left varicocele, while total testicular volume correlated positively with sperm numbers and Inhibin B and inversely with FSH. However, only abstinence, total testicular volume, varicocele grade and obesity (BMI > 30 kg/m2) were independently significantly related to total sperm count. Compared with those with BMI sperm count (mean 324 versus 231 million, P = 0.013) and Inhibin B (187 versus 140 pg/ml, P < 0.001) but not FSH (3.4 versus 4.0 IU/l, P = 0.6). Obese fertile men appear to have reduced testicular function. Whether this is cause or effect, i.e. adiposity impairing spermatogenesis or reduced testicular function promoting fat deposition, remains to be determined.

Dairy consumption is inversely associated with type 2 diabetes: dose-response meta-analysis of prospective cohort studies

NARCIS (Netherlands)

Gijsbers, L.; Geleijnse, J.M.; Soedamah-Muthu, S.S.

2011-01-01

Observational studies suggest an inverse association between dairy intake and incident type 2 diabetes, but the quantity of dairy is not known. Previous meta-analyses did not take into account the type of dairy product. Therefore, we examined dose-response associations between the intake of total

The significance of platelet-associated immunoglobulin G in non-thrombocytopenic patients with systemic lupus erythematosus

DEFF Research Database (Denmark)

Sørensen, P G; Mickley, H; Fristed, P

1985-01-01

The possible pathogenetic significance of platelet-associated immunoglobulin G in systemic lupus erythematosus (SLE) has been studied, using a semiquantitative immunofluorescence technique. The study included 22 patients suffering from SLE during the period 1973-81. Thirteen patients had various ...

The Omega-3 Index Is Inversely Associated with Depressive Symptoms among Individuals with Elevated Oxidative Stress Biomarkers123

Science.gov (United States)

Bigornia, Sherman J; Falcón, Luis M; Ordovás, José M; Lai, Chao-Qiang

2016-01-01

Background: Omega-3 (n–3) fatty acid (FA) consumption is thought to improve depressive symptoms. However, current evidence is limited, and whether this association exists among Puerto Ricans, a population burdened by depression, remains uncertain. Objectives: We examined the association between ω-3 FA biomarkers and depressive symptoms as well as the potential influence of oxidative stress. Methods: Baseline and longitudinal analyses were conducted in the Boston Puerto Rican Health Study (n = 787; participants aged 57 ± 0.52 y, 73% women). Urinary 8-hydroxy-2′-deoxyguanosine (8-OHdG) concentration, a measure of oxidative stress, and erythrocyte FA composition were collected at baseline. We calculated the omega-3 index as the sum of eicosapentaenoic and docosahexaenoic acids, expressed as a percentage of total FAs. Baseline and 2-y depressive symptoms were characterized by using the Center for Epidemiological Studies–Depression Scale (CES-D). Statistical analyses included linear and logistic regression. Results: Urinary 8-OHdG concentration tended to modify the relation between the erythrocyte omega-3 index and baseline CES-D score (P-interaction = 0.10). In stratified analyses, the omega-3 index was inversely associated with CES-D score (β = −1.74, SE = 0.88; P = 0.02) among those in the top quartile of 8-OHdG concentration but not among those in the lower quartiles. The relation between the omega-3 index and CES-D at 2 y was more clearly modified by 8-OHdG concentration (P-interaction = 0.04), where the omega-3 index was inversely associated with CES-D at 2 y, adjusted for baseline (β = −1.66, SE = 0.66; P = 0.02), only among those with elevated 8-OHdG concentrations. Among individuals not taking antidepressant medications and in the top tertile of urinary 8-OHdG concentration, the omega-3 index was associated with significantly lower odds of a CES-D score ≥16 at baseline (OR: 0.72; 95% CI: 0.53, 0.96) but not at 2 y (OR: 0.83; 95% CI: 0.60, 1

Inverse association between yerba mate consumption and idiopathic Parkinson's disease. A case-control study.

Science.gov (United States)

Gatto, Emilia Mabel; Melcon, Carlos; Parisi, Virginia L; Bartoloni, Leonardo; Gonzalez, Claudio D

2015-09-15

Yerba mate tea is a very common beverage in some countries of South America. We conducted a case-control study on an individual basis using hospital records to investigate the association between Parkinson's disease (PD) and yerba mate intake. A case was defined as an age of ≥ 40 years with ≥ 1 year of PD. Each case was individually matched by two controls. Exposure was measured by yerba mate consumption, coffee, tea, and alcohol intake and smoking status. The sample consisted of 223 PD patients (mean age 68 years and mean disease duration 7.3 years) and 406 controls. There was an inverse association between yerba mate "bombilla" consumption and PD (OR 0.64, 95% CI: 0.54-0.76, p=0.00001). A multivariate analysis with a logistic regression adjusted by sex, alcohol intake and smoking provided the following results: yerba mate (OR 0.63, 95% CI: 0.53-0.76), tea (OR 0.60, 95% CI: 0.42-0.86), coffee (OR 0.51, 95% CI: 0.35-0.73). We found an inverse association between yerba mate consumption and PD. These results led us to hypothesize that yerba mate may have a potential protective role in the development of PD. Copyright © 2015 Elsevier B.V. All rights reserved.

Non-destructive testing: significant facts

International Nuclear Information System (INIS)

Espejo, Hector; Ruch, Marta C.

2006-01-01

In the last fifty years different organisations, both public and private, have been assigned to the mission of introducing into the country the most relevant aspects of the modern technological discipline 'Non Destructive Testing' (NDT) through a manifold of activities, such as training and education, research, development, technical assistance and services, personnel qualification/certification and standardisation. A review is given of the significant facts in this process, in which the Argentine Atomic Energy Commission, CNEA, played a leading part, a balance of the accomplishments is made and a forecast of the future of the activity is sketched. (author) [es

Early detection of crop injury from herbicide glyphosate by leaf biochemical parameter inversion

Science.gov (United States)

Early detection of crop injury from glyphosate is of significant importance in crop management. In this paper, we attempt to detect glyphosate-induced crop injury by PROSPECT (leaf optical PROperty SPECTra model) inversion through leaf hyperspectral reflectance measurements for non-Glyphosate-Resist...

A healthy lifestyle index is associated with reduced risk of colorectal adenomatous polyps among non-users of non-steroidal anti-inflammatory drugs.

Science.gov (United States)

Tabung, Fred K; Steck, Susan E; Burch, James B; Chen, Chin-Fu; Zhang, Hongmei; Hurley, Thomas G; Cavicchia, Philip; Alexander, Melannie; Shivappa, Nitin; Creek, Kim E; Lloyd, Stephen C; Hebert, James R

2015-02-01

In a Columbia, South Carolina-based case-control study, we developed a healthy lifestyle index from five modifiable lifestyle factors (smoking, alcohol intake, physical activity, diet, and body mass index), and examined the association between this lifestyle index and the risk of colorectal adenomatous polyps (adenoma). Participants were recruited from a local endoscopy center and completed questionnaires related to lifestyle behaviors prior to colonoscopy. We scored responses on each of five lifestyle factors as unhealthy (0 point) or healthy (1 point) based on current evidence and recommendations. We added the five scores to produce a combined lifestyle index for each participant ranging from 0 (least healthy) to 5 (healthiest), which was dichotomized into unhealthy (0-2) and healthy (3-5) lifestyle scores. We used logistic regression to calculate odds ratios (OR) and 95% confidence intervals (CI) for adenoma with adjustment for multiple covariates. We identified 47 adenoma cases and 91 controls. In the main analyses, there was a statistically nonsignificant inverse association between the dichotomous (OR 0.54; 95% CI 0.22, 1.29) and continuous (OR 0.75; 95% CI 0.51, 1.10) lifestyle index and adenoma. Odds of adenoma were significantly modified by the use of non-steroidal anti-inflammatory drugs (NSAIDs) (p(interaction) = 0.04). For participants who reported no use of NSAIDs, those in the healthy lifestyle category had a 72% lower odds of adenoma as compared to those in the unhealthy category (OR 0.28; 95% CI 0.08, 0.98), whereas a one-unit increase in the index significantly reduced odds of adenoma by 53% (OR 0.47; 95% CI 0.26, 0.88). Although these findings should be interpreted cautiously given our small sample size, our results suggest that higher scores from this index are associated with reduced odds of adenomas, especially in non-users of NSAIDs. Lifestyle interventions are required to test this approach as a strategy to prevent colorectal adenomatous

Satisfaction (sexual, life, relationship, and mental health) is associated directly with penile-vaginal intercourse, but inversely with other sexual behavior frequencies.

Science.gov (United States)

Brody, Stuart; Costa, Rui Miguel

2009-07-01

Some sex therapists and educators assume that many sexual behaviors provide comparable sexual satisfaction. Evidence is required to determine whether sexual behaviors differ in their associations with both sexual satisfaction and satisfaction with other aspects of life. To test the hypothesis that satisfaction with sex life, life in general, sexual partnership, and mental health correlates directly with frequency of penile-vaginal intercourse (PVI) and inversely with frequency of both masturbation and partnered sexual activity excluding PVI (noncoital sex). A representative sample of 2,810 Swedes reported frequency of PVI, noncoital sex, and masturbation during the past 30 days, and degree of satisfaction with their sex life, life in general, partnership, and mental health. Multivariate analyses (for the sexes separately and combined) considering the different satisfaction parameters as dependent variables, and the different types of sexual activities (and age) as putative predictors. For both sexes, multivariate analyses revealed that PVI frequency was directly associated with all satisfaction measures (part correlation = 0.50 with sexual satisfaction), masturbation frequency was independently inversely associated with almost all satisfaction measures, and noncoital sex frequencies independently inversely associated with some satisfaction measures (and uncorrelated with the rest). Age did not confound the results. The results are consistent with evidence that specifically PVI frequency, rather than other sexual activities, is associated with sexual satisfaction, health, and well-being. Inverse associations between satisfaction and masturbation are not due simply to insufficient PVI.

Inverse association between the frequency of nut consumption and obesity among Iranian population: Isfahan Healthy Heart Program.

Science.gov (United States)

Mohammadifard, Noushin; Yazdekhasti, Narges; Stangl, Gabriele I; Sarrafzadegan, Nizal

2015-09-01

Recently, controversies have arisen concerning the association between nut intake and obesity. This study was performed to investigate the relationship between nut consumption and obesity among Iranian adults. In a cross-sectional survey, 9,660 randomly chosen adults aged ≥19 years were selected based on gender, age and their settlement distributions in three districts of central Iran in 2007. Nutritional behaviors including regular intake of walnuts, almonds, pistachios, hazelnuts and sunflower seed were assessed by validated 48-item-food-frequency questionnaire and a 24-h recall questionnaire. Using hierarchical logistic regression test, odds ratio (OR) 95% CI of obesity based on nut consumption was determined in an unadjusted and four adjusted models. The results showed a significant association between high nut consumption and lower prevalence of overweight or general obesity as well as abdominal obesity in women (p = 0.01 and p = 0.047, respectively), but not men. The frequency of nut consumption was associated with lower risk of overweight or general obesity [OR (95% CI) 0.57 (0.38-0.86)] and abdominal obesity [OR (95% CI) 0.51 (0.28-0.95)] only in women. After adjusting for gender, age and other potential confounders, the strength of the associations was blunted, but they were still significant. Frequent nuts and seeds consumption, particularly ≥1 time/day, had an inverse association with all classes of obesity among women.

Association between cancer and contact allergy: a linkage study

DEFF Research Database (Denmark)

Engkilde, Kaare; Thyssen, Jacob P; Menné, Torkil

2011-01-01

by logistic regression analysis. Results An inverse association between contact allergy and non-melanoma skin- and breast cancer, respectively, was identified in both sexes, and an inverse trend for brain cancer was found in women with contact allergy. Additionally, a positive association between contact...... allergy and bladder cancer was found. Conclusion The inverse associations support the immunosurveillance hypothesis (ie, individuals with an allergy are less likely to get cancer due to a triggered immune system), while the positive association with bladder cancer could be due to accumulations of chemical...

Joint inversion of hydraulic head and self-potential data associated with harmonic pumping tests

Science.gov (United States)

Soueid Ahmed, A.; Jardani, A.; Revil, A.; Dupont, J. P.

2016-09-01

Harmonic pumping tests consist in stimulating an aquifer by the means of hydraulic stimulations at some discrete frequencies. The inverse problem consisting in retrieving the hydraulic properties is inherently ill posed and is usually underdetermined when considering the number of well head data available in field conditions. To better constrain this inverse problem, we add self-potential data recorded at the ground surface to the head data. The self-potential method is a passive geophysical method. Its signals are generated by the groundwater flow through an electrokinetic coupling. We showed using a 3-D saturated unconfined synthetic aquifer that the self-potential method significantly improves the results of the harmonic hydraulic tomography. The hydroelectric forward problem is obtained by solving first the Richards equation, describing the groundwater flow, and then using the result in an electrical Poisson equation describing the self-potential problem. The joint inversion problem is solved using a reduction model based on the principal component geostatistical approach. In this method, the large prior covariance matrix is truncated and replaced by its low-rank approximation, allowing thus for notable computational time and storage savings. Three test cases are studied, to assess the validity of our approach. In the first test, we show that when the number of harmonic stimulations is low, combining the harmonic hydraulic and self-potential data does not improve the inversion results. In the second test where enough harmonic stimulations are performed, a significant improvement of the hydraulic parameters is observed. In the last synthetic test, we show that the electrical conductivity field required to invert the self-potential data can be determined with enough accuracy using an electrical resistivity tomography survey using the same electrodes configuration as used for the self-potential investigation.

Directive and non-directive food-related parenting practices: Associations between an expanded conceptualization of food-related parenting practices and child dietary intake and weight outcomes.

Science.gov (United States)

Loth, K A; Friend, S; Horning, M L; Neumark-Sztainer, D; Fulkerson, J A

2016-12-01

This study examines associations between an expanded conceptualization of food-related parenting practices, specifically, directive and non-directive control, and child weight (BMI z-score) and dietary outcomes [Healthy Eating Index (HEI) 2010, daily servings fruits/vegetables] within a sample of parent-child dyads (8-12 years old; n = 160). Baseline data from the Healthy Home Offerings via the Mealtime Environment (HOME Plus) randomized controlled trial was used to test associations between directive and non-directive control and child dietary outcomes and weight using multiple regression analyses adjusted for parental education. Overall variance explained by directive and non-directive control constructs was also calculated. Markers of directive control included pressure-to-eat and food restriction, assessed using subscales from the Child Feeding Questionnaire; markers of non-directive control were assessed with a parental role modeling scale and a home food availability inventory in which an obesogenic home food environment score was assigned based on the types and number of unhealthful foods available within the child's home food environment. Food restriction and pressure-to-eat were positively and negatively associated with BMI z-scores, respectively, but not with dietary outcomes. An obesogenic home food environment was inversely associated with both dietary outcomes; parental role modeling of healthful eating was positively associated with both dietary outcomes. Neither non-directive behavioral construct was significantly associated with BMI z-scores. Greater total variance in BMI-z was explained by directive control; greater total variance in dietary outcomes was explained by non-directive control. Including a construct of food-related parenting practices with separate markers for directive and non-directive control should be considered for future research. These concepts address different forms of parental control and, in the present study, yielded

Docosahexaenoic acid status at 9 months is inversely associated with communicative skills in 3-year-old girls

DEFF Research Database (Denmark)

Engel, Sara; Tronhjem, Kathrine Marie Hagerup; Hellgren, Lars

2013-01-01

by the parents using third edition of the Ages and Stages Questionnaire (ASQ-3). RBC DHA levels ranged from 2.2% to 12.6% of the RBC fatty acids. The age of reaching milestones correlated with psychomotor development, particularly with gross motor function at 3 years. An association between milestones and later...... personal and social skills was also observed, but only for girls. In girls, RBC-DHA was found to be inversely correlated with communication at 3 years of age (odds ratio = 0.69, 95% confidence interval: 0.56-0.86, P = 0.001), but no other associations with psychomotor development or milestones were found....... The results from study indicate that DHA status at 9 months may not have a pronounced beneficial effect on psychomotor development in early childhood and that communicative skills at 3 years of age may even be inversely associated with early RBC-DHA levels in girls....

Numerical solution of a coefficient inverse problem with multi-frequency experimental raw data by a globally convergent algorithm

Science.gov (United States)

Nguyen, Dinh-Liem; Klibanov, Michael V.; Nguyen, Loc H.; Kolesov, Aleksandr E.; Fiddy, Michael A.; Liu, Hui

2017-09-01

We analyze in this paper the performance of a newly developed globally convergent numerical method for a coefficient inverse problem for the case of multi-frequency experimental backscatter data associated to a single incident wave. These data were collected using a microwave scattering facility at the University of North Carolina at Charlotte. The challenges for the inverse problem under the consideration are not only from its high nonlinearity and severe ill-posedness but also from the facts that the amount of the measured data is minimal and that these raw data are contaminated by a significant amount of noise, due to a non-ideal experimental setup. This setup is motivated by our target application in detecting and identifying explosives. We show in this paper how the raw data can be preprocessed and successfully inverted using our inversion method. More precisely, we are able to reconstruct the dielectric constants and the locations of the scattering objects with a good accuracy, without using any advanced a priori knowledge of their physical and geometrical properties.

Identification of polymorphic inversions from genotypes

Directory of Open Access Journals (Sweden)

Cáceres Alejandro

2012-02-01

Full Text Available Abstract Background Polymorphic inversions are a source of genetic variability with a direct impact on recombination frequencies. Given the difficulty of their experimental study, computational methods have been developed to infer their existence in a large number of individuals using genome-wide data of nucleotide variation. Methods based on haplotype tagging of known inversions attempt to classify individuals as having a normal or inverted allele. Other methods that measure differences between linkage disequilibrium attempt to identify regions with inversions but unable to classify subjects accurately, an essential requirement for association studies. Results We present a novel method to both identify polymorphic inversions from genome-wide genotype data and classify individuals as containing a normal or inverted allele. Our method, a generalization of a published method for haplotype data 1, utilizes linkage between groups of SNPs to partition a set of individuals into normal and inverted subpopulations. We employ a sliding window scan to identify regions likely to have an inversion, and accumulation of evidence from neighboring SNPs is used to accurately determine the inversion status of each subject. Further, our approach detects inversions directly from genotype data, thus increasing its usability to current genome-wide association studies (GWAS. Conclusions We demonstrate the accuracy of our method to detect inversions and classify individuals on principled-simulated genotypes, produced by the evolution of an inversion event within a coalescent model 2. We applied our method to real genotype data from HapMap Phase III to characterize the inversion status of two known inversions within the regions 17q21 and 8p23 across 1184 individuals. Finally, we scan the full genomes of the European Origin (CEU and Yoruba (YRI HapMap samples. We find population-based evidence for 9 out of 15 well-established autosomic inversions, and for 52 regions

Unified dark energy-dark matter model with inverse quintessence

Energy Technology Data Exchange (ETDEWEB)

Ansoldi, Stefano [ICRA — International Center for Relativistic Astrophysics, INFN — Istituto Nazionale di Fisica Nucleare, and Dipartimento di Matematica e Informatica, Università degli Studi di Udine, via delle Scienze 206, I-33100 Udine (UD) (Italy); Guendelman, Eduardo I., E-mail: ansoldi@fulbrightmail.org, E-mail: guendel@bgu.ac.il [Department of Physics, Ben-Gurion University of the Negeev, Beer-Sheva 84105 (Israel)

2013-05-01

We consider a model where both dark energy and dark matter originate from the coupling of a scalar field with a non-canonical kinetic term to, both, a metric measure and a non-metric measure. An interacting dark energy/dark matter scenario can be obtained by introducing an additional scalar that can produce non constant vacuum energy and associated variations in dark matter. The phenomenology is most interesting when the kinetic term of the additional scalar field is ghost-type, since in this case the dark energy vanishes in the early universe and then grows with time. This constitutes an ''inverse quintessence scenario'', where the universe starts from a zero vacuum energy density state, instead of approaching it in the future.

Unified dark energy-dark matter model with inverse quintessence

International Nuclear Information System (INIS)

Ansoldi, Stefano; Guendelman, Eduardo I.

2013-01-01

We consider a model where both dark energy and dark matter originate from the coupling of a scalar field with a non-canonical kinetic term to, both, a metric measure and a non-metric measure. An interacting dark energy/dark matter scenario can be obtained by introducing an additional scalar that can produce non constant vacuum energy and associated variations in dark matter. The phenomenology is most interesting when the kinetic term of the additional scalar field is ghost-type, since in this case the dark energy vanishes in the early universe and then grows with time. This constitutes an ''inverse quintessence scenario'', where the universe starts from a zero vacuum energy density state, instead of approaching it in the future

Serum γ-Glutamyl Transferase Is Inversely Associated with Bone Mineral Density Independently of Alcohol Consumption

Directory of Open Access Journals (Sweden)

Han Seok Choi

2016-03-01

Full Text Available Backgroundγ-Glutamyl transferase (GGT is a well-known marker of chronic alcohol consumption or hepatobiliary diseases. A number of studies have demonstrated that serum levels of GGT are independently associated with cardiovascular and metabolic disorders. The purpose of this study was to test if serum GGT levels are associated with bone mineral density (BMD in Korean adults.MethodsA total of 462 subjects (289 men and 173 women, who visited Severance Hospital for medical checkup, were included in this study. BMD was measured using dual energy X-ray absorptiometry. Cross-sectional association between serum GGT and BMD was evaluated.ResultsAs serum GGT levels increased from the lowest tertile (tertile 1 to the highest tertile (tertile 3, BMD decreased after adjusting for confounders such as age, body mass index, amount of alcohol consumed, smoking, regular exercise, postmenopausal state (in women, hypertension, diabetes mellitus, and hypercholesterolemia. A multiple linear regression analysis showed a negative association between log-transformed serum GGT levels and BMD. In a multiple logistic regression analysis, tertile 3 of serum GGT level was associated with an increased risk for low bone mass compared to tertile 1 (odds ratio, 2.271; 95% confidence interval, 1.340 to 3.850; P=0.002.ConclusionSerum GGT level was inversely associated with BMD in Korean adults. Further study is necessary to fully elucidate the mechanism of the inverse relationship.

Improvements on a non-invasive, parameter-free approach to inverse form finding

Science.gov (United States)

Landkammer, P.; Caspari, M.; Steinmann, P.

2018-04-01

Our objective is to determine the optimal undeformed workpiece geometry (material configuration) within forming processes when the prescribed deformed geometry (spatial configuration) is given. For solving the resulting shape optimization problem—also denoted as inverse form finding—we use a novel parameter-free approach, which relocates in each iteration the material nodal positions as design variables. The spatial nodal positions computed by an elasto-plastic finite element (FE) forming simulation are compared with their prescribed values. The objective function expresses a least-squares summation of the differences between the computed and the prescribed nodal positions. Here, a recently developed shape optimization approach (Landkammer and Steinmann in Comput Mech 57(2):169-191, 2016) is investigated with a view to enhance its stability and efficiency. Motivated by nonlinear optimization theory a detailed justification of the algorithm is given. Furthermore, a classification according to shape changing design, fixed and controlled nodal coordinates is introduced. Two examples with large elasto-plastic strains demonstrate that using a superconvergent patch recovery technique instead of a least-squares (L2)-smoothing improves the efficiency. Updating the interior discretization nodes by solving a fictitious elastic problem also reduces the number of required FE iterations and avoids severe mesh distortions. Furthermore, the impact of the inclusion of the second deformation gradient in the Hessian of the Quasi-Newton approach is analyzed. Inverse form finding is a crucial issue in metal forming applications. As a special feature, the approach is designed to be coupled in a non-invasive fashion to arbitrary FE software.

Non medical factors associated with psychological disorders in cancer patients

International Nuclear Information System (INIS)

Iqbal, A.; Intikhab, K.; Saeed, K.

2002-01-01

Objective: To find out major non-medial factors associated with psychological disorders in cancer patients. Design: An observational study conducted on adult cancer patients. Place and Duration of Study: The study was conducted at Shaukat Khanum Memorial Cancer Hospital and Research Center Lahore Pakistan from January 1999. Patients and Methods: Two hundred and twenty-four newly-diagnosed adult cancer patients were interviewed by the clinical psychologist and data was collected regarding non-medical causal factors, patients age, gender family support system, general home atmosphere and marital status. Collected data was analyzed by utilizing. SPSS for windows version 10.0. Results: Of the 224 patients 142 (63.4%) reported non-medical factors causing psychological distress and 82 (36.6%) reported that medical sources are the most distressing. Ten most common non-medical sources of developing psychological disorders were identified. It was observed that family support system and general home atmosphere were significantly associated with the development of psychological disorders whereas the other variables such as age, gender and marital status had no significant relationship with the non Medical factors. Conclusion: It was concluded that non-medical factors causing psychological problems are significant in cancer patients. The results suggest that we should identify these factors and target psychosocial intervention for those patients most at risk. (author)

SMARANDACHE NON-ASSOCIATIVE RINGS

OpenAIRE

Vasantha, Kandasamy

2002-01-01

An associative ring is just realized or built using reals or complex; finite or infinite by defining two binary operations on it. But on the contrary when we want to define or study or even introduce a non-associative ring we need two separate algebraic structures say a commutative ring with 1 (or a field) together with a loop or a groupoid or a vector space or a linear algebra. The two non-associative well-known algebras viz. Lie algebras and Jordan algebras are mainly built using a vecto...

Free testosterone concentration is inversely associated with markers of liver fibrosis in men with type 2 diabetes mellitus.

Science.gov (United States)

Miyauchi, Shozo; Miyake, Teruki; Miyazaki, Masumi; Eguchi, Toru; Niiya, Tetsuji; Yamamoto, Shin; Senba, Hidenori; Furukawa, Shinya; Matsuura, Bunzo; Hiasa, Yoichi

2017-12-28

The association between serum testosterone level and liver fibrosis in patients with non-alcoholic fatty liver disease is unclear. To clarify this association, we investigated the relationship between serum free testosterone concentration and markers of liver fibrosis in men with type 2 diabetes mellitus but no obvious features of alcohol consumption. This retrospective observational cross-sectional study enrolled 248 men with type 2 diabetes mellitus. The FIB-4 index was measured as a marker of liver fibrosis, and multiple linear regression analysis was performed to examine its association with serum free testosterone concentration. In addition, the 7S domain of type IV collagen (IV-7S) was examined in 140 of the 248 patients. The mean free testosterone concentration was 10.6 ± 6.8 pg/mL and the means of the FIB-4 index and IV-7S were 1.64 ± 1.19 and 4.02 ± 1.11 ng/mL, respectively. After adjusting for all relevant variables, serum free testosterone concentrations were inversely associated with both the FIB-4 index and IV-7S (β; -0.28, P diabetes mellitus may help to predict progression to advanced liver disease. Identifying patients at risk may help to prevent the development of cirrhosis and hepatocellular carcinoma.

Non-alcoholic steatohepatitis : Clinical significance and pathogenesis

NARCIS (Netherlands)

de Knegt, RJ

2001-01-01

Non-alcoholic steatohepatitis (NASH) is a form of liver disease resembling alcoholic liver disease in a patient who does not consume significant amounts of alcohol. Since its first description in 1980 it has been recognized with increasing frequency. The natural course is relatively benign, but

Monitoring of Cyclic Steam Stimulation by Inversion of Surface Tilt Measurements

Science.gov (United States)

Maharramov, M.; Zoback, M. D.

2014-12-01

Temperature and pressure changes associated with the cyclic steam simulation (CSS) used in heavy oil production from sands are accompanied by significant deformation. Inversion of geomechanical data may provide a potentially powerful reservoir monitoring tool where geomechanical effects are significant. Induced pore pressure changes can be inverted from measurable surface deformations by solving an inverse problem of poroelasticity. In this work, we apply this approach to estimating pore pressure changes from surface tilt measurements at a heavy oil reservoir undergoing cyclic steam simulation. Steam was injected from November 2007 through January 2008. Surface tilt measurements were collected from 25 surface tilt stations during this period. The injection ran in two overlapping phases: Phase 1 ran from the beginning of the injection though mid-December, and Phase 2 overlapped with Phase 1 and ran through the beginning of January. During Phase 1 steam was injected in the western part of the reservoir, followed by injection in the eastern part in Phase 2. The pore pressure evolution was inverted from daily tilt measurements using regularized constrained least squares fitting, the results are shown on the plot. Estimated induced pore pressure change (color scale), observed daily incremental tilts (green arrows) and modeled daily incremental tilts (red arrows) are shown in three panels corresponding to two and five weeks of injection, and the end of injection period. DGPS measurements available for a single location were used as an additional inversion constraint. The results indicate that the pore pressure increase in the reservoir follows the same pattern as the steam injection, from west to east. This qualitative behaviour is independent of the amount of regularization, indirectly validating our inversion approach. Patches of lower pressure appear to be stable with regard to regularization and may provide valuable insight into the efficiency of steam injection

Association of Exposure to Fine Particulate Matter and Risk Factors of Non-Communicable Diseases in Children and Adolescents

Directory of Open Access Journals (Sweden)

Parinaz Poursafa

2017-10-01

Full Text Available Background: Risk factors of non-communicable disease (NCD origin from early life, and exposure to environmental pollutant may be a predisposing factor. This study aimed to investigate the association of air quality index (AQI and fine particulate matter (PM2.5 with some NCD risk factors in a sample of Iranian children and adolescents. Materials and Methods: This cross-sectional study was conducted in 2014 to 2016 among children and adolescents, aged 6-18 years, in Isfahan, Iran. Physical examination, including weight, height, and blood pressure, was conducted by standard methods. Fasting blood sample was obtained for fasting blood glucose, total cholesterol, high density lipoprotein-cholesterol, low-density lipoprotein- cholesterol, and triglycerides. The mean AQI and PM2.5 values from the study time till one year prior to the survey were used. Multiple linear regression analysis was conducted for the association of AQI and PM2.5 with other variables. Results: Participants consisted of 186 children and adolescents with mean (SD age of 10.52(2.38 years. Exposure to higher level of PM2.5 had significant associations with higher levels of systolic blood pressure, low-density lipoprotein cholesterol, and triglycerides. It also had positive relationship with other risk factors and inverse association with low-density lipoprotein cholesterol (LDL-C, but these associations were not statistically significant. The corresponding figures were not significant for AQI. Conclusion: At current study results showed that exposure to higher levels of fine particulates was associated with some NCD risk factors in children and adolescents. Early life prevention of NCDs can lead to large reductions in disease risk; adverse effects of ambient pollutants should be considered in this regard.

Cruciferous vegetable intake is inversely associated with lung cancer risk among smokers: a case-control study

Directory of Open Access Journals (Sweden)

Zhang Yuesheng

2010-04-01

Full Text Available Abstract Background Inverse associations between cruciferous vegetable intake and lung cancer risk have been consistently reported. However, associations within smoking status subgroups have not been consistently addressed. Methods We conducted a hospital-based case-control study with lung cancer cases and controls matched on smoking status, and further adjusted for smoking status, duration, and intensity in the multivariate models. A total of 948 cases and 1743 controls were included in the analysis. Results Inverse linear trends were observed between intake of fruits, total vegetables, and cruciferous vegetables and risk of lung cancer (ORs ranged from 0.53-0.70, with P for trend Conclusions Our findings are consistent with the smoking-related carcinogen-modulating effect of isothiocyanates, a group of phytochemicals uniquely present in cruciferous vegetables. Our data support consumption of a diet rich in cruciferous vegetables may reduce the risk of lung cancer among smokers.

Non centered minor hysteresis loops evaluation based on exponential parameters transforms of the modified inverse Jiles–Atherton model

International Nuclear Information System (INIS)

Hamimid, M.; Mimoune, S.M.; Feliachi, M.; Atallah, K.

2014-01-01

In this present work, a non centered minor hysteresis loops evaluation is performed using the exponential transforms (ET) of the modified inverse Jiles–Atherton model parameters. This model improves the non centered minor hysteresis loops representation. The parameters of the non centered minor hysteresis loops are obtained from exponential expressions related to the major ones. The parameters of minor loops are obtained by identification using the stochastic optimization method “simulated annealing”. The four parameters of JA model (a,α, k and c) obtained by this transformation are applied only in both ascending and descending branches of the non centered minor hysteresis loops while the major ones are applied to the rest of the cycle. This proposal greatly improves both branches and consequently the minor loops. To validate this model, calculated non-centered minor hysteresis loops are compared with measured ones and good agreements are obtained

Non-stationarities significantly distort short-term spectral, symbolic and entropy heart rate variability indices

International Nuclear Information System (INIS)

Magagnin, Valentina; Bassani, Tito; Bari, Vlasta; Turiel, Maurizio; Porta, Alberto; Maestri, Roberto; Pinna, Gian Domenico

2011-01-01

The autonomic regulation is non-invasively estimated from heart rate variability (HRV). Many methods utilized to assess autonomic regulation require stationarity of HRV recordings. However, non-stationarities are frequently present even during well-controlled experiments, thus potentially biasing HRV indices. The aim of our study is to quantify the potential bias of spectral, symbolic and entropy HRV indices due to non-stationarities. We analyzed HRV series recorded in healthy subjects during uncontrolled daily life activities typical of 24 h Holter recordings and during predetermined levels of robotic-assisted treadmill-based physical exercise. A stationarity test checking the stability of the mean and variance over short HRV series (about 300 cardiac beats) was utilized to distinguish stationary periods from non-stationary ones. Spectral, symbolic and entropy indices evaluated solely over stationary periods were contrasted with those derived from all the HRV segments. When indices were calculated solely over stationary series, we found that (i) during both uncontrolled daily life activities and controlled physical exercise, the entropy-based complexity indices were significantly larger; (ii) during uncontrolled daily life activities, the spectral and symbolic indices linked to sympathetic modulation were significantly smaller and those associated with vagal modulation were significantly larger; (iii) while during uncontrolled daily life activities, the variance of spectral, symbolic and entropy rate indices was significantly larger, during controlled physical exercise, it was smaller. The study suggests that non-stationarities increase the likelihood to overestimate the contribution of sympathetic control and affect the power of statistical tests utilized to discriminate conditions and/or groups

Association of history of allergies and influenza-like infections with laryngeal cancer in a case-control study.

Science.gov (United States)

Filippidis, Filippos T; Schwartz, Stephen M; Becker, Nikolaus; Dyckhoff, Gerhard; Kirschfink, Michael; Dietz, Andreas; Becher, Heiko; Ramroth, Heribert

2015-08-01

Prior studies suggest that history of allergy and infections early in life might be inversely associated with cancer. We explored the association between allergies, recent influenza infections and laryngeal cancer risk. We used data from a case-control study which included 229 cases of laryngeal cancer and 769 population controls matched for age and sex. History of a physician-diagnosed allergy, influenza-like infections in the past 5 years, smoking, alcohol consumption and occupational exposure to carcinogens were self-reported. Allergies were classified into two groups (Type I and Type IV), according to the underlying immunologic mechanism. Conditional logistic regression models were fitted using laryngeal cancer as the outcome, adjusting for smoking, alcohol consumption and occupational exposure and stratified for age and sex. Having any allergy was not associated significantly with laryngeal cancer. Although Type I and Type IV allergies were non-significantly associated with laryngeal cancer, Type IV allergies showed a strong inverse association after adjusting for smoking and alcohol (OR 0.50, 95 % CI 0.22-1.2). Participants who reported at least one influenza-like infection during the past 5 years were significantly less likely to have laryngeal cancer (OR 0.57, 95 % CI 0.39-0.81). After considering fever (≥38.5 °C) as a criterion for influenza infection, the association between influenza infection and laryngeal cancer was even stronger (OR 0.29, 95 % CI 0.13-0.63). We found no significant association between any allergy and laryngeal cancer, some indication of an inverse association between Type IV allergy and laryngeal cancer, whereas recent influenza infections were inversely associated with laryngeal cancer risk.

New Insights on the Uncertainties in Finite-Fault Earthquake Source Inversion

KAUST Repository

Razafindrakoto, Hoby

2015-04-01

New Insights on the Uncertainties in Finite-Fault Earthquake Source Inversion Hoby Njara Tendrisoa Razafindrakoto Earthquake source inversion is a non-linear problem that leads to non-unique solutions. The aim of this dissertation is to understand the uncertainty and reliability in earthquake source inversion, as well as to quantify variability in earthquake rupture models. The source inversion is performed using a Bayesian inference. This technique augments optimization approaches through its ability to image the entire solution space which is consistent with the data and prior information. In this study, the uncertainty related to the choice of source-time function and crustal structure is investigated. Three predefined analytical source-time functions are analyzed; isosceles triangle, Yoffe with acceleration time of 0.1 and 0.3 s. The use of the isosceles triangle as source-time function is found to bias the finite-fault source inversion results. It accelerates the rupture to propagate faster compared to that of the Yoffe function. Moreover, it generates an artificial linear correlation between parameters that does not exist for the Yoffe source-time functions. The effect of inadequate knowledge of Earth’s crustal structure in earthquake rupture models is subsequently investigated. The results show that one-dimensional structure variability leads to parameters resolution changes, with a broadening of the posterior 5 PDFs and shifts in the peak location. These changes in the PDFs of kinematic parameters are associated with the blurring effect of using incorrect Earth structure. As an application to real earthquake, finite-fault source models for the 2009 L’Aquila earthquake are examined using one- and three-dimensional crustal structures. One- dimensional structure is found to degrade the data fitting. However, there is no significant effect on the rupture parameters aside from differences in the spatial slip extension. Stable features are maintained for both

Non-regularized inversion method from light scattering applied to ferrofluid magnetization curves for magnetic size distribution analysis

International Nuclear Information System (INIS)

Rijssel, Jos van; Kuipers, Bonny W.M.; Erné, Ben H.

2014-01-01

A numerical inversion method known from the analysis of light scattering by colloidal dispersions is now applied to magnetization curves of ferrofluids. The distribution of magnetic particle sizes or dipole moments is determined without assuming that the distribution is unimodal or of a particular shape. The inversion method enforces positive number densities via a non-negative least squares procedure. It is tested successfully on experimental and simulated data for ferrofluid samples with known multimodal size distributions. The created computer program MINORIM is made available on the web. - Highlights: • A method from light scattering is applied to analyze ferrofluid magnetization curves. • A magnetic size distribution is obtained without prior assumption of its shape. • The method is tested successfully on ferrofluids with a known size distribution. • The practical limits of the method are explored with simulated data including noise. • This method is implemented in the program MINORIM, freely available online

Uncertainties in the 2004 Sumatra–Andaman source through nonlinear stochastic inversion of tsunami waves

Science.gov (United States)

Venugopal, M.; Roy, D.; Rajendran, K.; Guillas, S.; Dias, F.

2017-01-01

Numerical inversions for earthquake source parameters from tsunami wave data usually incorporate subjective elements to stabilize the search. In addition, noisy and possibly insufficient data result in instability and non-uniqueness in most deterministic inversions, which are barely acknowledged. Here, we employ the satellite altimetry data for the 2004 Sumatra–Andaman tsunami event to invert the source parameters. We also include kinematic parameters that improve the description of tsunami generation and propagation, especially near the source. Using a finite fault model that represents the extent of rupture and the geometry of the trench, we perform a new type of nonlinear joint inversion of the slips, rupture velocities and rise times with minimal a priori constraints. Despite persistently good waveform fits, large uncertainties in the joint parameter distribution constitute a remarkable feature of the inversion. These uncertainties suggest that objective inversion strategies should incorporate more sophisticated physical models of seabed deformation in order to significantly improve the performance of early warning systems. PMID:28989311

The value of qualitative and quantitative assessment of lesion to cerebral cortex signal ratio on double inversion recovery sequence in the differentiation of demyelinating plaques from non-specific T2 hyperintensities

Energy Technology Data Exchange (ETDEWEB)

Hamcan, Salih; Battal, Bilal; Akgun, Veysel; Sari, Sebahattin; Tasar, Mustafa [Gulhane Military Medical School, Department of Radiology, Etlik, Ankara (Turkey); Oz, Oguzhan; Tasdemir, Serdar [Gulhane Military Medical School, Department of Neurology, Ankara (Turkey); Bozkurt, Yalcin [Golcuk Military Hospital, Department of Radiology, Kocaeli (Turkey)

2017-02-15

To assess the usefulness of the visual assessment and to determine diagnostic value of the lesion-to-cerebral cortex signal ratio (LCSR) measurement in the differentiation of demyelinating plaques and non-specific T2 hyperintensities on double inversion recovery (DIR) sequence. DIR and fluid-attenuated inversion recovery (FLAIR) sequences of 25 clinically diagnosed multiple sclerosis (MS) patients and 25 non-MS patients with non-specific T2-hyperintense lesions were evaluated visually and LCSRs were measured by two observers independently. On DIR sequence, the calculated mean LCSR ± SD for demyelinating plaques and non-specific T2-hyperintense lesions were 1.60 ± 0.26 and 0.75 ± 0.19 for observer1, and 1.61 ± 0.27 and 0.74 ± 0.19 for observer2. LCSRs of demyelinating plaques were significantly higher than other non-specific T2-hyperintense lesions on DIR sequence. By using the visual assessment demyelinating plaques were differentiated from non-specific T2-hyperintensities with 92.8 % sensitivity, 97.5 % specificity and 95.1 % accuracy for observer1 and 92.8 % sensitivity, 95 % specificity and 93.9 % accuracy for observer2. Visual assessment and LCSR measurement on DIR sequence seems to be useful for differentiating demyelinating MS plaques from supratentorial non-specific T2 hyperintensities. This feature can be used for diagnosis of MS particularly in patients with only supratentorial T2-hyperintense lesions who are categorized as radiologically possible MS. (orig.)

Inverse association of leptin levels with renal cell carcinoma: results from a case-control study.

Science.gov (United States)

Spyridopoulos, Themistoklis N; Petridou, Eleni Th; Dessypris, Nick; Terzidis, Agapios; Skalkidou, Alkistis; Deliveliotis, Charalambos; Chrousos, George P

2009-01-01

Leptin is primarily produced in adipose tissue and appears to play a modulatory role between metabolism and immunity. Given that obesity, a state of chronic inflammation, is an established risk factor for Renal Cell Carcinoma (RCC), we investigated the association between plasma leptin levels and RCC risk. This case-control study included 70 patients with newly diagnosed, histologically confirmed RCC and 280 age-, gender- and district of residence-matched controls. Anthropometric data, socio-demographic variables, medical history, lifestyle habits and dietary data were derived from a personal interview. Serum leptin and adiponectin levels were determined using standard commercial kits. Adjusted odds ratios for RCC risk were derived through multiple logistic regression analyses. Leptin levels were inversely associated with RCC risk (OR: 0.53, CI: 0.28- 0.99, p = 0.05), even after controlling for potential confounding factors, such as Body Mass Index (BMI), recent weight change, history of diabetes mellitus and other obesity related hormones, notably adiponectin. The precise mechanism linking obesity with RCC remains unclear; however, the inverse association of leptin with RCC might be attributed, at least in part, to hormonal cross-talk with complex neuron-endocrine and immune circuits. These findings, if confirmed in prospective and interventional studies, might further elucidate the underlying mechanisms.

Surface waves tomography and non-linear inversion in the southeast Carpathians

International Nuclear Information System (INIS)

Raykova, R.B.; Panza, G.F.

2005-11-01

A set of shear-wave velocity models of the lithosphere-asthenosphere system in the southeast Carpathians is determined by the non-linear inversion of surface wave group velocity data, obtained from a tomographic analysis. The local dispersion curves are assembled for the period range 7 s - 150 s, combining regional group velocity measurements and published global Rayleigh wave dispersion data. The lithosphere-asthenosphere velocity structure is reliably reconstructed to depths of about 250 km. The thickness of the lithosphere in the region varies from about 120 km to 250 km and the depth of the asthenosphere between 150 km and 250 km. Mantle seismicity concentrates where the high velocity lid is detected just below the Moho. The obtained results are in agreement with recent seismic refraction, receiver function, and travel time P-wave tomography investigations in the region. The similarity among the results obtained from different kinds of structural investigations (including the present work) highlights some new features of the lithosphere-asthenosphere system in southeast Carpathians, as the relatively thin crust under Transylvania basin and Vrancea zone. (author)

Male infertility associated with de novo pericentric inversion of chromosome 1.

Science.gov (United States)

Balasar, Özgür; Zamani, Ayşe Gül; Balasar, Mehmet; Acar, Hasan

2017-12-01

Inversion occurs after two breaks in a chromosome have happened and the segment rotates 180° before reinserting. Inversion carriers have produced abnormal gametes if there is an odd number crossing- over between the inverted and the normal homologous chromosomes causing a duplication or deletion. Reproductive risks such as infertility, abortion, stillbirth and birth of malformed child would be expected in that case. A 54-year- old male patient was consulted to our clinic for primary infertility. The routine chromosome study were applied using peripheral blood lymphocyte cultures and analyzed by giemsa-trypsin-giemsa (GTG) banding, and centromer banding (C-banding) stains. Y chromosome microdeletions in the azoospermia factor (AZF) regions were analyzed with polymerase chain reaction. Additional test such as fluorescence in situ hybridization (FISH) was used to detect the sex-determining region of the Y chromosome (SRY). Semen analysis showed azoospermia. A large pericentric inversion of chromosome 1 46,XY, inv(1) (p22q32) was found in routine chromosome analysis. No microdeletions were seen in AZF regions. In our patient the presence of SRY region was observed by using FISH technique with SRY-specific probe. Men who have pericentric inversion of chromosome 1, appear to be at risk for infertility brought about by spermatogenic breakdown. The etiopathogenic relationship between azoospermia and pericentric inversion of chromosome 1 is discussed.

Association of hypovitaminosis Dwith persistent non-specific musculoskeletal pains

International Nuclear Information System (INIS)

Alam, H.M.A.; Kamran, M.; Rehman, S.U.; Khan, D.A.; Hussain, K.

2017-01-01

The study was conducted in Pakistani population to find association of vitamin D deficiency with persistent non-specific musculoskeletal pains by comparing with pain free controls. Study Design: Case control study. Material and Methods: Patients aged 12 years or more presenting to Medical OPD with persistent nonspecific musculoskeletal pains for more than 3 months were selected as cases, while healthy individuals served as controls Results: A total of 60 cases (patients with persistent non-specific pains) presenting to medical outpatients department at Military Hospital Rawalpindi and 60 controls were studied. Mean age of cases was 43.9 +- 14.0 years and amongst controls were 33.2 +- 17.8 years. Mean serum vitamin D level of 32.8 nmol/L was reported in cases whereas mean serum vitamin D level amongst controls was 26.7 +- 17.8 nmol/L. Hypovitaminosis D amongst cases and controls was 86.6% and 95% respectively. The proportion of vitamin D deficiency did not differ significantly as compared to controls. There was non-significant difference in proportion of deficiency amongst cases and controls. Conclusion: Overall there was no association between persistent non-specific musculoskeletal pains and vitamin D deficiency. (author)

Eosinophil inversely associates with type 2 diabetes and insulin resistance in Chinese adults.

Directory of Open Access Journals (Sweden)

Liying Zhu

Full Text Available CONTEXT: Limited population-based study focused on relationship between eosinophil and type 2 diabetes (T2D. OBJECTIVES: We aimed to evaluate the relationship between peripheral eosinophil percentage and glucose metabolism and insulin resistance in a large sample size of Chinese population aged 40 and older. DESIGN AND METHODS: A cross-sectional study was performed among 9,111 Chinese adults including 3,561 men and 5,550 women. The glucose metabolism status was confirmed by 75-g oral glucose tolerance test. Homeostasis model assessment of insulin resistance index and serum insulin levels were used to evaluate insulin resistance. Homeostasis model assessment-B was used to evaluate β cell function. RESULTS: The average age of participants was 58.5 years. The prevalence of T2D decreased across the tertiles of eosinophil percentage (21.3%, 18.2% and 16.9%, P<0.0001. Each one tertile increase of eosinophil percentage inversely associated with risk of T2D when referred not only to normal glucose tolerance (NGT (odds ratio (OR 0.81, 95% CI 0.76-0.87, P< 0.0001, but also to impaired glucose regulation (OR 0.89, 95% CI 0.83-0.97, P = 0.006, respectively, after adjustment for the confounding factors. Compared with the first tertile, the third tertile of eosinophil percentage associated with a 23% decrease of insulin resistance in NGT participants after full adjustments (P = 0.005. Each 1-standard deviation of increment of eosinophil percentage associated with a 37% decrease of insulin resistance (P = 0.005. CONCLUSIONS: Higher peripheral eosinophil percentage was associated with decreased risk of T2D. The inverse relation to insulin resistance was detected in NGT participants.

Identification of chromosome 7 inversion breakpoints in an autistic family narrows candidate region for autism susceptibility.

Science.gov (United States)

Cukier, Holly N; Skaar, David A; Rayner-Evans, Melissa Y; Konidari, Ioanna; Whitehead, Patrice L; Jaworski, James M; Cuccaro, Michael L; Pericak-Vance, Margaret A; Gilbert, John R

2009-10-01

Chromosomal breaks and rearrangements have been observed in conjunction with autism and autistic spectrum disorders. A chromosomal inversion has been previously reported in autistic siblings, spanning the region from approximately 7q22.1 to 7q31. This family is distinguished by having multiple individuals with autism and associated disabilities. The region containing the inversion has been strongly implicated in autism by multiple linkage studies, and has been particularly associated with language defects in autism as well as in other disorders with language components. Mapping of the inversion breakpoints by FISH has localized the inversion to the region spanning approximately 99-108.75 Mb of chromosome 7. The proximal breakpoint has the potential to disrupt either the coding sequence or regulatory regions of a number of cytochrome P450 genes while the distal region falls in a relative gene desert. Copy number variant analysis of the breakpoint regions detected no duplication or deletion that could clearly be associated with disease status. Association analysis in our autism data set using single nucleotide polymorphisms located near the breakpoints showed no significant association with proximal breakpoint markers, but has identified markers near the distal breakpoint ( approximately 108-110 Mb) with significant associations to autism. The chromosomal abnormality in this family strengthens the case for an autism susceptibility gene in the chromosome 7q22-31 region and targets a candidate region for further investigation.

Whole-Grain Intake, Reflected by Dietary Records and Biomarkers, Is Inversely Associated with Circulating Insulin and Other Cardiometabolic Markers in 8- to 11-Year-Old Children

DEFF Research Database (Denmark)

Damsgaard, Camilla T.; Biltoft-Jensen, Anja Pia; Tetens, Inge

2017-01-01

.05) as well as insulin (P = 0.003), which also tended to be inversely associated with whole-grain rye intake (P = 0.11). Adjustment for fat mass index did not change the associations. The C17-to-C21 alkylresorcinol ratio, reflecting whole-grain rye to wheat intake, was inversely associated with insulin (P

Recovering convexity in non-associated plasticity

Science.gov (United States)

Francfort, Gilles A.

2018-03-01

We quickly review two main non-associated plasticity models, the Armstrong-Frederick model of nonlinear kinematic hardening and the Drucker-Prager cap model. Non-associativity is commonly thought to preclude any kind of variational formulation, be it in a Hencky-type (static) setting, or when considering a quasi-static evolution because non-associativity destroys convexity. We demonstrate that such an opinion is misguided: associativity (and convexity) can be restored at the expense of the introduction of state variable-dependent dissipation potentials.

Creep and inverse stress relaxation behaviors of carbon nanotube yarns.

Science.gov (United States)

Misak, H E; Sabelkin, V; Miller, L; Asmatulu, R; Mall, S

2013-12-01

Creep, creep recovery and inverse stress relaxation behaviors of carbon nanotube yarns that consisted of 1-, 30-, and 100-yarn(s) were characterized. Primary and secondary creep stages were observed over the duration of 336 h. The primary creep stage lasted for about 4 h at an applied load equal to 75% of the ultimate tensile strength. The total strain in the primary stage was significantly larger in the carbon nanotube multi-yarn than in the carbon nanotube 1-yarn. In the secondary stage, 1-yarn also had a smaller steady state strain rate than the multi-yarn, and it was independent of number of yarns in multi-yarn. Strain response under cyclic creep loading condition was comparable to its counterpart in non-cyclic (i.e., standard) creep test except that strain response during the first cycle was slightly different from the subsequent cycles. Inverse creep (i.e., strain recovery) was observed in the 100-yarn during the cyclic creep tests after the first unloading cycle. Furthermore, inverse stress relaxation of the multi-yarns was characterized. Inverse stress relaxation was larger and for longer duration with the larger number of yarns.

The attitude inversion method of geostationary satellites based on unscented particle filter

Science.gov (United States)

Du, Xiaoping; Wang, Yang; Hu, Heng; Gou, Ruixin; Liu, Hao

2018-04-01

The attitude information of geostationary satellites is difficult to be obtained since they are presented in non-resolved images on the ground observation equipment in space object surveillance. In this paper, an attitude inversion method for geostationary satellite based on Unscented Particle Filter (UPF) and ground photometric data is presented. The inversion algorithm based on UPF is proposed aiming at the strong non-linear feature in the photometric data inversion for satellite attitude, which combines the advantage of Unscented Kalman Filter (UKF) and Particle Filter (PF). This update method improves the particle selection based on the idea of UKF to redesign the importance density function. Moreover, it uses the RMS-UKF to partially correct the prediction covariance matrix, which improves the applicability of the attitude inversion method in view of UKF and the particle degradation and dilution of the attitude inversion method based on PF. This paper describes the main principles and steps of algorithm in detail, correctness, accuracy, stability and applicability of the method are verified by simulation experiment and scaling experiment in the end. The results show that the proposed method can effectively solve the problem of particle degradation and depletion in the attitude inversion method on account of PF, and the problem that UKF is not suitable for the strong non-linear attitude inversion. However, the inversion accuracy is obviously superior to UKF and PF, in addition, in the case of the inversion with large attitude error that can inverse the attitude with small particles and high precision.

Projected change in characteristics of near surface temperature inversions for southeast Australia

Science.gov (United States)

Ji, Fei; Evans, Jason Peter; Di Luca, Alejandro; Jiang, Ningbo; Olson, Roman; Fita, Lluis; Argüeso, Daniel; Chang, Lisa T.-C.; Scorgie, Yvonne; Riley, Matt

2018-05-01

Air pollution has significant impacts on human health. Temperature inversions, especially near surface temperature inversions, can amplify air pollution by preventing convective movements and trapping pollutants close to the ground, thus decreasing air quality and increasing health issues. This effect of temperature inversions implies that trends in their frequency, strength and duration can have important implications for air quality. In this study, we evaluate the ability of three reanalysis-driven high-resolution regional climate model (RCM) simulations to represent near surface inversions at 9 sounding sites in southeast Australia. Then we use outputs of 12 historical and future RCM simulations (each with three time periods: 1990-2009, 2020-2039, and 2060-2079) from the NSW/ACT (New South Wales/Australian Capital Territory) Regional Climate Modelling (NARCliM) project to investigate changes in near surface temperature inversions. The results show that there is a substantial increase in the strength of near surface temperature inversions over southeast Australia which suggests that future inversions may intensify poor air quality events. Near surface inversions and their future changes have clear seasonal and diurnal variations. The largest differences between simulations are associated with the driving GCMs, suggesting that the large-scale circulation plays a dominant role in near surface inversion strengths.

Serum chemerin levels are inversely associated with renal function in a general population

DEFF Research Database (Denmark)

Zylla, Stephanie; Rettig, Rainer; Völzke, Henry

2018-01-01

OBJECTIVE: Chemerin has been found to be highly expressed in the kidneys of rodents and has been suggested to affect metabolic syndrome (MetS)-related phenotypes which are in turn related to kidney damage. Only few clinical studies have addressed the relation between circulating chemerin and renal...... function in humans, and no population-based analyses have yet been performed. The potential influence of MetS-related phenotypes on the assumed association has been largely neglected. We aimed to investigate the association of serum chemerin with renal function in a general population with special regard......GFR and revealed that each increase in chemerin per 25 ng/mL was associated with an about threefold higher odds of chronic kidney disease [odds ratio 2.72 (95% confidence interval 2.26-3.29)]. CONCLUSIONS: Our results demonstrate a strong inverse association between serum chemerin levels and renal function...

The Cauchy problem for non-linear Klein-Gordon equations

International Nuclear Information System (INIS)

Simon, J.C.H.; Taflin, E.

1993-01-01

We consider in R n+1 , n≥2, the non-linear Klein-Gordon equation. We prove for such an equation that there is neighbourhood of zero in a Hilbert space of initial conditions for which the Cauchy problem has global solutions and on which there is asymptotic completeness. The inverse of the wave operator linearizes the non-linear equation. If, moreover, the equation is manifestly Poincare covariant then the non-linear representation of the Poincare-Lie algebra, associated with the non-linear Klein-Gordon equation is integrated to a non-linear representation of the Poincare group on an invariant neighbourhood of zero in the Hilbert space. This representation is linearized by the inverse of the wave operator. The Hilbert space is, in both cases, the closure of the space of the differentiable vectors for the linear representation of the Poincare group, associated with the Klein-Gordon equation, with respect to a norm defined by the representation of the enveloping algebra. (orig.)

Stochastic Gabor reflectivity and acoustic impedance inversion

Science.gov (United States)

Hariri Naghadeh, Diako; Morley, Christopher Keith; Ferguson, Angus John

2018-02-01

To delineate subsurface lithology to estimate petrophysical properties of a reservoir, it is possible to use acoustic impedance (AI) which is the result of seismic inversion. To change amplitude to AI, removal of wavelet effects from the seismic signal in order to get a reflection series, and subsequently transforming those reflections to AI, is vital. To carry out seismic inversion correctly it is important to not assume that the seismic signal is stationary. However, all stationary deconvolution methods are designed following that assumption. To increase temporal resolution and interpretation ability, amplitude compensation and phase correction are inevitable. Those are pitfalls of stationary reflectivity inversion. Although stationary reflectivity inversion methods are trying to estimate reflectivity series, because of incorrect assumptions their estimations will not be correct, but may be useful. Trying to convert those reflection series to AI, also merging with the low frequency initial model, can help us. The aim of this study was to apply non-stationary deconvolution to eliminate time variant wavelet effects from the signal and to convert the estimated reflection series to the absolute AI by getting bias from well logs. To carry out this aim, stochastic Gabor inversion in the time domain was used. The Gabor transform derived the signal’s time-frequency analysis and estimated wavelet properties from different windows. Dealing with different time windows gave an ability to create a time-variant kernel matrix, which was used to remove matrix effects from seismic data. The result was a reflection series that does not follow the stationary assumption. The subsequent step was to convert those reflections to AI using well information. Synthetic and real data sets were used to show the ability of the introduced method. The results highlight that the time cost to get seismic inversion is negligible related to general Gabor inversion in the frequency domain. Also

Inversion effects for faces and objects in developmental prosopagnosia

DEFF Research Database (Denmark)

Klargaard, Solja K; Starrfelt, Randi; Gerlach, Christian

2018-01-01

The disproportionate face inversion effect (dFIE) concerns the finding that face recognition is more affected by inversion than recognition of non-face objects; an effect assumed to reflect that face recognition relies on special operations. Support for this notion comes from studies showing...... that face processing in developmental prosopagnosia (DP) is less affected by inversion than it is in normal subjects, and that DPs may even display face inversion superiority effects, i.e. better processing of inverted compared to upright faces. To date, however, there are no reports of direct comparisons...... between inversion effects for faces and objects, investigating whether the altered inversion effect in DP is specific to faces. We examined this question by comparing inversion effects for faces and cars in two otherwise identical recognition tasks in a group of DPs (N = 16) and a matched control group...

An Entropic Estimator for Linear Inverse Problems

Directory of Open Access Journals (Sweden)

Amos Golan

2012-05-01

Full Text Available In this paper we examine an Information-Theoretic method for solving noisy linear inverse estimation problems which encompasses under a single framework a whole class of estimation methods. Under this framework, the prior information about the unknown parameters (when such information exists, and constraints on the parameters can be incorporated in the statement of the problem. The method builds on the basics of the maximum entropy principle and consists of transforming the original problem into an estimation of a probability density on an appropriate space naturally associated with the statement of the problem. This estimation method is generic in the sense that it provides a framework for analyzing non-normal models, it is easy to implement and is suitable for all types of inverse problems such as small and or ill-conditioned, noisy data. First order approximation, large sample properties and convergence in distribution are developed as well. Analytical examples, statistics for model comparisons and evaluations, that are inherent to this method, are discussed and complemented with explicit examples.

Non-Gaussianity in a quasiclassical electronic circuit

Science.gov (United States)

Suzuki, Takafumi J.; Hayakawa, Hisao

2017-05-01

We study the non-Gaussian dynamics of a quasiclassical electronic circuit coupled to a mesoscopic conductor. Non-Gaussian noise accompanying the nonequilibrium transport through the conductor significantly modifies the stationary probability density function (PDF) of the flux in the dissipative circuit. We incorporate weak quantum fluctuation of the dissipative LC circuit with a stochastic method and evaluate the quantum correction of the stationary PDF. Furthermore, an inverse formula to infer the statistical properties of the non-Gaussian noise from the stationary PDF is derived in the classical-quantum crossover regime. The quantum correction is indispensable to correctly estimate the microscopic transfer events in the QPC with the quasiclassical inverse formula.

Dietary Fiber Intake Is Inversely Associated with Periodontal Disease among US Adults.

Science.gov (United States)

Nielsen, Samara Joy; Trak-Fellermeier, Maria Angelica; Joshipura, Kaumudi; Dye, Bruce A

2016-12-01

Approximately 47% of adults in the United States have periodontal disease. Dietary guidelines recommend a diet providing adequate fiber. Healthier dietary habits, particularly an increased fiber intake, may contribute to periodontal disease prevention. Our objective was to evaluate the relation of dietary fiber intake and its sources with periodontal disease in the US adult population (≥30 y of age). Data from 6052 adults participating in NHANES 2009-2012 were used. Periodontal disease was defined (according to the CDC/American Academy of Periodontology) as severe, moderate, mild, and none. Intake was assessed by 24-h dietary recalls. The relation between periodontal disease and dietary fiber, whole-grain, and fruit and vegetable intakes were evaluated by using multivariate models, adjusting for sociodemographic characteristics and dentition status. In the multivariate logistic model, the lowest quartile of dietary fiber was associated with moderate-severe periodontitis (compared with mild-none) compared with the highest dietary fiber intake quartile (OR: 1.30; 95% CI: 1.00, 1.69). In the multivariate multinomial logistic model, intake in the lowest quartile of dietary fiber was associated with higher severity of periodontitis than dietary fiber intake in the highest quartile (OR: 1.27; 95% CI: 1.00, 1.62). In the adjusted logistic model, whole-grain intake was not associated with moderate-severe periodontitis. However, in the adjusted multinomial logistic model, adults consuming whole grains in the lowest quartile were more likely to have more severe periodontal disease than were adults consuming whole grains in the highest quartile (OR: 1.32; 95% CI: 1.08, 1.62). In fully adjusted logistic and multinomial logistic models, fruit and vegetable intake was not significantly associated with periodontitis. We found an inverse relation between dietary fiber intake and periodontal disease among US adults ≥30 y old. Periodontal disease was associated with low whole

Some problems associated with the inversion of polar magnetic substorm data recorded at the Earth's surface

International Nuclear Information System (INIS)

Mareschal, M.

1975-01-01

The major thrust of this dissertation was to test an original method for resolving the current system associated with polar magnetic substorms from ground based magnetic observations. This method is based on a general technique of inversion reviewed by Wiggins in 1972 and appears to give quite satisfactory results, at least, when the current system considered is simulated by a three-dimensional current system consisting of field-aligned currents flowing down to the ionosphere, westward in the ionosphere, and back up again to the magnetosphere. Conclusions suggest that, for the purpose of inverting polar magnetic substorm data with the use of the three-dimensional model of current, the Earth's induction effects can be simulated by introducing a perfectly conducting layer inside the Earth. However, the depth of this equivalent conductor should be allowed to vary with the source frequency as the substorm develops with time. To determine how satisfactorily each model parameter could be expected to be resolved during the process of inversion, a study of the magnetic disturbance variations under specific parameter variations was then performed. The results of that study were encouraging enough to foster the inversion of an actual polar magnetic substorm data, the event of June 15, 1970. Despite the success of the enterprise, it seems reasonable to suggest that the technique of inversion should be further tested before being systematically used to resolve polar magnetic substorms

Inverse source problems in elastodynamics

Science.gov (United States)

Bao, Gang; Hu, Guanghui; Kian, Yavar; Yin, Tao

2018-04-01

We are concerned with time-dependent inverse source problems in elastodynamics. The source term is supposed to be the product of a spatial function and a temporal function with compact support. We present frequency-domain and time-domain approaches to show uniqueness in determining the spatial function from wave fields on a large sphere over a finite time interval. The stability estimate of the temporal function from the data of one receiver and the uniqueness result using partial boundary data are proved. Our arguments rely heavily on the use of the Fourier transform, which motivates inversion schemes that can be easily implemented. A Landweber iterative algorithm for recovering the spatial function and a non-iterative inversion scheme based on the uniqueness proof for recovering the temporal function are proposed. Numerical examples are demonstrated in both two and three dimensions.

Prognostic significance of overexpressed long non-coding RNA TUG1 in patients with clear cell renal cell carcinoma.

Science.gov (United States)

Wang, P-Q; Wu, Y-X; Zhong, X-D; Liu, B; Qiao, G

2017-01-01

The long non-coding RNAs (lncRNAs) study has gradually become one of the hot topics in the field of RNA biology. However, little is known about the pathological role of lncRNA TUG1 in clear cell renal cell carcinoma (ccRCC) patients. This study attempted to investigate the association of lncRNA TUG1 expression with progression and prognosis in ccRCC patients. Using qRT-PCR, the expression of TUG1 was measured in 203 ccRCC tissues and 45 adjacent non-cancerous tissues. Then, the relationships between TUG1 level and the clinicopathological factors of patients with ccRCC were analyzed. The prognostic significance was evaluated using Kaplan-Meier and Cox regression analyses. The relative level of TUG1was significantly higher in ccRCC tissues compared to the adjacent non-tumor tissues (p TUG1 was associated significantly with histological grade, tumor stage, lymph node metastasis and distant metastasis (all p TUG1 expression levels were associated with a shorter overall survival (p TUG1 expression was an independent prognostic marker of poor outcome. These findings suggested that TUG1 may act as a tumor promoter in ccRCC and could serve as a potential therapeutic target for this tumor.

Association of circulating adipokines with metabolic dyslipidemia in obese versus non-obese individuals.

Science.gov (United States)

Rahimlou, Mehran; Mirzaei, Khadijeh; Keshavarz, Seyed Ali; Hossein-Nezhad, Arash

2016-01-01

Previous studies have shown that circulating adipokines may play an important role in the pathogenesis of some obesity related chronic disease such as dyslipidemia and type2 diabetes mellitus. The aim of the present study was to investigate the association between vaspin, omentin-1 and retinol binding protein-4 levels with metabolic dyslipidemia (MD) criteria in obese and non-obese individuals. The study was conducted on 170 obese and 81 non-obese individuals. After collecting the blood samples, serum levels metabolic parameters as well as three circulating adipokines and body composition were measured. No significant difference was noted regarding the mean serum levels of omentin-1 and vaspin between the obese and non-obese groups, while, serum level of RBP4 was significantly higher in the non-obese group. We found the 0.22 increased risk of MD in obese individuals with higher RBP4 concentration. After the adjustment for confounding factors, this association was still significant. No significant association was noted between MD and its components relative risks with omentin-1 and vaspin levels. Our study demonstrated that circulating RBP4 was significantly higher in the obese individuals which may increase the risk of MD in them. Further researches are needed to address this association. Copyright © 2015 Diabetes India. Published by Elsevier Ltd. All rights reserved.

Coupled land surface-subsurface hydrogeophysical inverse modeling to estimate soil organic carbon content and explore associated hydrological and thermal dynamics in the Arctic tundra

Science.gov (United States)

Phuong Tran, Anh; Dafflon, Baptiste; Hubbard, Susan S.

2017-09-01

Quantitative characterization of soil organic carbon (OC) content is essential due to its significant impacts on surface-subsurface hydrological-thermal processes and microbial decomposition of OC, which both in turn are important for predicting carbon-climate feedbacks. While such quantification is particularly important in the vulnerable organic-rich Arctic region, it is challenging to achieve due to the general limitations of conventional core sampling and analysis methods, and to the extremely dynamic nature of hydrological-thermal processes associated with annual freeze-thaw events. In this study, we develop and test an inversion scheme that can flexibly use single or multiple datasets - including soil liquid water content, temperature and electrical resistivity tomography (ERT) data - to estimate the vertical distribution of OC content. Our approach relies on the fact that OC content strongly influences soil hydrological-thermal parameters and, therefore, indirectly controls the spatiotemporal dynamics of soil liquid water content, temperature and their correlated electrical resistivity. We employ the Community Land Model to simulate nonisothermal surface-subsurface hydrological dynamics from the bedrock to the top of canopy, with consideration of land surface processes (e.g., solar radiation balance, evapotranspiration, snow accumulation and melting) and ice-liquid water phase transitions. For inversion, we combine a deterministic and an adaptive Markov chain Monte Carlo (MCMC) optimization algorithm to estimate a posteriori distributions of desired model parameters. For hydrological-thermal-to-geophysical variable transformation, the simulated subsurface temperature, liquid water content and ice content are explicitly linked to soil electrical resistivity via petrophysical and geophysical models. We validate the developed scheme using different numerical experiments and evaluate the influence of measurement errors and benefit of joint inversion on the

Coupled land surface–subsurface hydrogeophysical inverse modeling to estimate soil organic carbon content and explore associated hydrological and thermal dynamics in the Arctic tundra

Directory of Open Access Journals (Sweden)

A. P. Tran

2017-09-01

Full Text Available Quantitative characterization of soil organic carbon (OC content is essential due to its significant impacts on surface–subsurface hydrological–thermal processes and microbial decomposition of OC, which both in turn are important for predicting carbon–climate feedbacks. While such quantification is particularly important in the vulnerable organic-rich Arctic region, it is challenging to achieve due to the general limitations of conventional core sampling and analysis methods, and to the extremely dynamic nature of hydrological–thermal processes associated with annual freeze–thaw events. In this study, we develop and test an inversion scheme that can flexibly use single or multiple datasets – including soil liquid water content, temperature and electrical resistivity tomography (ERT data – to estimate the vertical distribution of OC content. Our approach relies on the fact that OC content strongly influences soil hydrological–thermal parameters and, therefore, indirectly controls the spatiotemporal dynamics of soil liquid water content, temperature and their correlated electrical resistivity. We employ the Community Land Model to simulate nonisothermal surface–subsurface hydrological dynamics from the bedrock to the top of canopy, with consideration of land surface processes (e.g., solar radiation balance, evapotranspiration, snow accumulation and melting and ice–liquid water phase transitions. For inversion, we combine a deterministic and an adaptive Markov chain Monte Carlo (MCMC optimization algorithm to estimate a posteriori distributions of desired model parameters. For hydrological–thermal-to-geophysical variable transformation, the simulated subsurface temperature, liquid water content and ice content are explicitly linked to soil electrical resistivity via petrophysical and geophysical models. We validate the developed scheme using different numerical experiments and evaluate the influence of measurement errors and

A pericentric inversion of chromosome X disrupting F8 and resulting in haemophilia A.

Science.gov (United States)

Xin, Yu; Zhou, Jingyi; Ding, Qiulan; Chen, Changming; Wu, Xi; Wang, Xuefeng; Wang, Hongli; Jiang, Xiaofeng

2017-08-01

The frequency of X chromosome pericentric inversion is much less than that of autosome chromosome. We hereby characterise a pericentric inversion of X chromosome associated with severe factor VIII (FVIII) deficiency in a sporadic haemophilia A (HA) pedigree. PCR primer walking and genome walking strategies were adopted to identify the exact breakpoints of the inversion. Copy number variations (CNVs) of the F8 and the whole chromosomes were detected by AccuCopy and Affymetrix CytoScan High Definition (HD) assays, respectively. A karyotype analysis was performed by cytogenetic G banding technique. We identified a previously undescribed type of pericentric inversion of the X chromosome [inv(X)(p11.21q28)] in the proband with FVIII:C inversion segment was approximately 64.4% of the total chromosomal length. The karyotype analysis of the X chromosome confirmed the pericentric inversion of the X chromosome in the proband and his mother. A haplotype analysis traced the inversion to his maternal grandfather, who was not a somatic mosaic of the inversion. This finding indicated that the causative mutation may originate from his germ cells or a rare possibility of germ-cell mosaicism. The characterisation of pericentric inversion involving F8 extended the molecular mechanisms causing HA. The pericentric inversion rearrangement involves F8 by non-homologous end joining is responsible for pathogensis of severe HA. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Inversion of Gravity Anomalies Using Primal-Dual Interior Point Methods

Directory of Open Access Journals (Sweden)

Aaron A. Velasco

2016-06-01

Full Text Available Structural inversion of gravity datasets based on the use of density anomalies to derive robust images of the subsurface (delineating lithologies and their boundaries constitutes a fundamental non-invasive tool for geological exploration. The use of experimental techniques in geophysics to estimate and interpret di erences in the substructure based on its density properties have proven e cient; however, the inherent non-uniqueness associated with most geophysical datasets make this the ideal scenario for the use of recently developed robust constrained optimization techniques. We present a constrained optimization approach for a least squares inversion problem aimed to characterize 2-Dimensional Earth density structure models based on Bouguer gravity anomalies. The proposed formulation is solved with a Primal-Dual Interior-Point method including equality and inequality physical and structural constraints. We validate our results using synthetic density crustal structure models with varying complexity and illustrate the behavior of the algorithm using di erent initial density structure models and increasing noise levels in the observations. Based on these implementations, we conclude that the algorithm using Primal-Dual Interior-Point methods is robust, and its results always honor the geophysical constraints. Some of the advantages of using this approach for structural inversion of gravity data are the incorporation of a priori information related to the model parameters (coming from actual physical properties of the subsurface and the reduction of the solution space contingent on these boundary conditions.

Stratigraphic inversion of pre-stack multicomponent data; Inversion stratigraphique multicomposante avant sommation

Energy Technology Data Exchange (ETDEWEB)

Agullo, Y.

2005-09-15

This thesis present the extension of mono-component seismic pre-stack data stratigraphical inversion method to multicomponent data, with the objective of improving the determination of reservoir elastic parameters. In addiction to the PP pressure waves, the PS converted waves proved their interest for imaging under gas clouds; and their potential is highly significant for the characterization of lithologies, fluids, fractures... Nevertheless the simultaneous use ol PP and PS data remains problematic because of their different the time scales. To jointly use the information contained in PP and PS data, we propose a method in three steps first, mono-component stratigraphic inversions of PP then PS data; second, estimation of the PP to PS time conversion law; third, multicomponent stratigraphic inversion. For the second point, the estimation of the PP to PS conversion law is based on minimizing the difference between the S impedances obtained from PP and PS mono-component stratigraphic inversion. The pre-stack mono-component stratigraphic inversions was adapted to the case of multicomponent data by leaving each type of data in its own time scale in order to avoid the distortion of the seismic wavelet. The results obtained on a realistic synthetic PP-PS case show on one hand that determining PP to PS conversion law (from the mono-component inversion results) is feasible, and on the other hand that the joint inversion of PP and PS data with this conversion law improves the results compared to the mono-component inversion ones. Although this is presented within the framework of the PP and PS multi-component data, the developed methodology adapts directly to PP and SS data for example. (author)

Non-perturbational surface-wave inversion: A Dix-type relation for surface waves

Science.gov (United States)

Haney, Matt; Tsai, Victor C.

2015-01-01

We extend the approach underlying the well-known Dix equation in reflection seismology to surface waves. Within the context of surface wave inversion, the Dix-type relation we derive for surface waves allows accurate depth profiles of shear-wave velocity to be constructed directly from phase velocity data, in contrast to perturbational methods. The depth profiles can subsequently be used as an initial model for nonlinear inversion. We provide examples of the Dix-type relation for under-parameterized and over-parameterized cases. In the under-parameterized case, we use the theory to estimate crustal thickness, crustal shear-wave velocity, and mantle shear-wave velocity across the Western U.S. from phase velocity maps measured at 8-, 20-, and 40-s periods. By adopting a thin-layer formalism and an over-parameterized model, we show how a regularized inversion based on the Dix-type relation yields smooth depth profiles of shear-wave velocity. In the process, we quantitatively demonstrate the depth sensitivity of surface-wave phase velocity as a function of frequency and the accuracy of the Dix-type relation. We apply the over-parameterized approach to a near-surface data set within the frequency band from 5 to 40 Hz and find overall agreement between the inverted model and the result of full nonlinear inversion.

Down-regulation of p21 (CDKN1A/CIP1) is inversely associated with microsatellite instability and CpG island methylator phenotype (CIMP) in colorectal cancer.

Science.gov (United States)

Ogino, S; Kawasaki, T; Kirkner, G J; Ogawa, A; Dorfman, I; Loda, M; Fuchs, C S

2006-10-01

p21 (CDKN1A/CIP1/WAF1), one of the cyclin-dependent kinase inhibitors, plays a key role in regulating the cell cycle and is transcriptionally regulated by p53. Down-regulation of p21 is caused by TP53 mutations in colorectal cancer. CpG island methylator phenotype (CIMP) appears to be a distinct subtype of colorectal cancer with concordant methylation of multiple gene promoters and is associated with a high degree of microsatellite instability (MSI-H) and BRAF mutations. However, no study to date has evaluated the relationship between p21 expression and CIMP in colorectal cancer. The purpose of this study was to examine the inter-relationships between p21, p53, CIMP, MSI and KRAS/BRAF status in colorectal cancer. We utilized 737 relatively unbiased samples of colorectal cancers from two large prospective cohort studies. Using quantitative real-time PCR (MethyLight), we measured DNA methylation in five CIMP-specific gene promoters [CACNA1G, CDKN2A (p16/INK4A), CRABP1, MLH1 and NEUROG1]. CIMP-high (>or=4/5 methylated promoters) was diagnosed in 118 (16%) of the 737 tumours. We also assessed expression of p21 and p53 by immunohistochemistry. Among the 737 tumours, 371 (50%) showed p21 loss. Both p21 loss and p53 positivity were inversely associated with CIMP-high, MSI-H and BRAF mutations. The associations of p21 with these molecular features were still present after tumours were stratified by p53 status. In contrast, the associations of p53 positivity with the molecular features were no longer present after tumours were stratified by p21 status. When CIMP-high and non-CIMP-high tumours were stratified by MSI or KRAS/BRAF status, CIMP-high and MSI-H (but not BRAF mutations) were still inversely associated with p21 loss. In conclusion, down-regulation of p21 is inversely correlated with CIMP-high and MSI-H in colorectal cancer, independent of TP53 and BRAF status.

Serum bilirubin levels are inversely associated with PAI-1 and fibrinogen in Korean subjects.

Science.gov (United States)

Cho, Hyun Sun; Lee, Sung Won; Kim, Eun Sook; Shin, Juyoung; Moon, Sung Dae; Han, Je Ho; Cha, Bong Yun

2016-01-01

Oxidative stress may contribute to atherosclerosis and increased activation of the coagulation pathway. Bilirubin may reduce activation of the hemostatic system to inhibit oxidative stress, which would explain its cardioprotective properties shown in many epidemiological studies. This study investigated the association of serum bilirubin with fibrinogen and plasminogen activator inhibitor-1 (PAI-1), respectively. A cross-sectional analysis was performed on 968 subjects (mean age, 56.0 ± 11.2 years; 61.1% men) undergoing a general health checkup. Serum biochemistry was analyzed including bilirubin subtypes, insulin resistance (using homeostasis model of assessment [HOMA]), C-reactive protein (CRP), fibrinogen, and PAI-1. Compared with subjects with a total bilirubin (TB) concentration of 17.1 μmol/L had a smaller waist circumference, a lower triglyceride level, a lower prevalence of metabolic syndrome, and decreased HOMA-IR and CRP levels. Correlation analysis revealed linear relationships of fibrinogen with TB and direct bilirubin (DB), whereas PAI-1 was correlated with DB. After adjustment for confounding factors, bilirubin levels were inversely associated with fibrinogen and PAI-1 levels, respectively. Multivariate regression models showed a negative linear relationship between all types of bilirubin and fibrinogen, whereas there was a significant linear relationship between PAI-1 and DB. High bilirubin concentrations were independently associated with low levels of fibrinogen and PAI-1, respectively. The association between TB and PAI-1 was confined to the highest TB concentration category whereas DB showed a linear association with PAI-1. Bilirubin may protect against the development of atherothrombosis by reducing the hemostatic response. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Geodynamic inversion to constrain the non-linear rheology of the lithosphere

Science.gov (United States)

Baumann, T. S.; Kaus, Boris J. P.

2015-08-01

One of the main methods to determine the strength of the lithosphere is by estimating it's effective elastic thickness. This method assumes that the lithosphere is a thin elastic plate that floats on the mantle and uses both topography and gravity anomalies to estimate the plate thickness. Whereas this seems to work well for oceanic plates, it has given controversial results in continental collision zones. For most of these locations, additional geophysical data sets such as receiver functions and seismic tomography exist that constrain the geometry of the lithosphere and often show that it is rather complex. Yet, lithospheric geometry by itself is insufficient to understand the dynamics of the lithosphere as this also requires knowledge of the rheology of the lithosphere. Laboratory experiments suggest that rocks deform in a viscous manner if temperatures are high and stresses low, or in a plastic/brittle manner if the yield stress is exceeded. Yet, the experimental results show significant variability between various rock types and there are large uncertainties in extrapolating laboratory values to nature, which leaves room for speculation. An independent method is thus required to better understand the rheology and dynamics of the lithosphere in collision zones. The goal of this paper is to discuss such an approach. Our method relies on performing numerical thermomechanical forward models of the present-day lithosphere with an initial geometry that is constructed from geophysical data sets. We employ experimentally determined creep-laws for the various parts of the lithosphere, but assume that the parameters of these creep-laws as well as the temperature structure of the lithosphere are uncertain. This is used as a priori information to formulate a Bayesian inverse problem that employs topography, gravity, horizontal and vertical surface velocities to invert for the unknown material parameters and temperature structure. In order to test the general methodology

[Expression and significance of P-gp/mdr1 mRNA, MRP and LRP in non-Hodgkin's lymphoma].

Science.gov (United States)

Li, Le; Su, Li-ping; Ma, Li; Zhao, Jin; Zhu, Lei; Zhou, Yong-an

2009-03-01

To explore the expression and clinical significance of P-glycoprotein (P-gp)/mdr1mRNA, multidrug resistance-associated protein (MRP) and lung resistance protein (LRP) in newly diagnosed non-Hodgkin's lymphoma. mdr1 mRNA of in 41 patients with non-Hodgkin's lymphoma was assayed by semi-quantitative RT-PCR. The expressions of P-gp, MRP and LRP proteins in lymph node viable blasts were identified by flow cytometry. The results were compared with those obtained from control cases, and the correlation of the changes with clinical outcomes was analyzed. (1) Among the 41 cases, the positive expression of P-gp protein was detected in 8 cases, MRP in 7 cases, LRP in 15 cases, and mdr 1 mRNA in 11 cases. (2) The P-gp and LRP levels in NHL were significantly higher than those in control group, but MRP wasn't. The P-gp over-expression was significantly associated with mdr1mRNA (r = 0.396, P = 0.01). No correlation was showed among the expressions of P-gp, MRP and LRP. (3) Patients with P-gp expression had a poorer outcome of chemotherapy than those with P-gp-negative (P = 0.005). P-gp expression was significantly associated with higher clinical stage (P = 0.046) and elevated serum lactate dehydrogenase level (P = 0.032), but not associated with malignant degree (P = 0.298). MRP had no impact on the outcome of chemotherapy (P = 0.212), and wasn't significantly associated with higher clinical stage (P = 0.369), elevated LDH (P = 0.762) and higher malignant degree (P = 0.451). Patients with LRP expression had a poorer outcome of chemotherapy than those LRP-negative (P = 0.012). LRP expression was significantly associated with higher clinical stage (P = 0.0019), elevated LDH (P = 0.02) and higher malignant degree (P = 0.01). The data of this study indicate that P-gp and LRP expressions but not MRP expression are important in the mechanism of drug resistance associated with a poor clinical outcome in previously untreated NHL.

Testing causes for the European mid-Paleocene inversions

DEFF Research Database (Denmark)

Nielsen, S.B.; Stephenson, Randell; Hansen, D.L.

2006-01-01

For a period of approx. 20 Myr during the Late Cretaceous, the Paleozoic and Mesozoic rifts and basins on the European continent experienced compressional shortening and inversion. On the order of ~103m of erosion occurred along the inversion axes; the convergence of Africa and Europe has...... conventionally been held responsible. A second stage of inversion of the same structures occurred in the mid-Paleocene; however, this differed in structural style by being domal and non-ruptural with amplitudes on the order of ~102m. Furthermore, within the chronostratigraphic resolution, the onset of the mid......-Paleocene phase occurred synchronously at ~60 Ma. The different styles of inversion call for different explanations and, recently, the second phase of inversion has been explained by a relaxation or rotation (rather than further compression) of the in-plane stress field of the first Late Cretaceous phase...

A Comparison of Closed-Loop Performance of Multirotor Configurations Using Non-Linear Dynamic Inversion Control

Directory of Open Access Journals (Sweden)

Murray L. Ireland

2015-06-01

Full Text Available Multirotor is the umbrella term for the family of unmanned aircraft, which include the quadrotor, hexarotor and other vertical take-off and landing (VTOL aircraft that employ multiple main rotors for lift and control. Development and testing of novel multirotor designs has been aided by the proliferation of 3D printing and inexpensive flight controllers and components. Different multirotor configurations exhibit specific strengths, while presenting unique challenges with regards to design and control. This article highlights the primary differences between three multirotor platforms: a quadrotor; a fully-actuated hexarotor; and an octorotor. Each platform is modelled and then controlled using non-linear dynamic inversion. The differences in dynamics, control and performance are then discussed.

An Inversion Disrupting FAM134B Is Associated with Sensory Neuropathy in the Border Collie Dog Breed

Directory of Open Access Journals (Sweden)

Oliver P. Forman

2016-09-01

Full Text Available Sensory neuropathy in the Border Collie is a severe neurological disorder caused by the degeneration of sensory and, to a lesser extent, motor nerve cells with clinical signs starting between 2 and 7 months of age. Using a genome-wide association study approach with three cases and 170 breed matched controls, a suggestive locus for sensory neuropathy was identified that was followed up using a genome sequencing approach. An inversion disrupting the candidate gene FAM134B was identified. Genotyping of additional cases and controls and RNAseq analysis provided strong evidence that the inversion is causal. Evidence of cryptic splicing resulting in novel exon transcription for FAM134B was identified by RNAseq experiments. This investigation demonstrates the identification of a novel sensory neuropathy associated mutation, by mapping using a minimal set of cases and subsequent genome sequencing. Through mutation screening, it should be possible to reduce the frequency of or completely eliminate this debilitating condition from the Border Collie breed population.

Angle-domain Migration Velocity Analysis using Wave-equation Reflection Traveltime Inversion

KAUST Repository

Zhang, Sanzong

2012-11-04

The main difficulty with an iterative waveform inversion is that it tends to get stuck in a local minima associated with the waveform misfit function. This is because the waveform misfit function is highly non-linear with respect to changes in the velocity model. To reduce this nonlinearity, we present a reflection traveltime tomography method based on the wave equation which enjoys a more quasi-linear relationship between the model and the data. A local crosscorrelation of the windowed downgoing direct wave and the upgoing reflection wave at the image point yields the lag time that maximizes the correlation. This lag time represents the reflection traveltime residual that is back-projected into the earth model to update the velocity in the same way as wave-equation transmission traveltime inversion. The residual movemout analysis in the angle-domain common image gathers provides a robust estimate of the depth residual which is converted to the reflection traveltime residual for the velocity inversion. We present numerical examples to demonstrate its efficiency in inverting seismic data for complex velocity model.

Difference in Association of Obesity With Prostate Cancer Risk Between US African American and Non-Hispanic White Men in the Selenium and Vitamin E Cancer Prevention Trial (SELECT).

Science.gov (United States)

Barrington, Wendy E; Schenk, Jeannette M; Etzioni, Ruth; Arnold, Kathryn B; Neuhouser, Marian L; Thompson, Ian M; Lucia, M Scott; Kristal, Alan R

2015-06-01

African American men have the highest rates of prostate cancer incidence and mortality in the United States. Understanding underlying reasons for this disparity could identify preventive interventions important to African American men. To determine whether the association of obesity with prostate cancer risk differs between African American and non-Hispanic white men and whether obesity modifies the excess risk associated with African American race. Prospective study of 3398 African American and 22,673 non-Hispanic white men who participated in the Selenium and Vitamin E Cancer Prevention Trial (2001-2011) with present analyses completed in 2014. Total, low-grade (Gleason score American men and a corresponding 1453, 898, and 441 cases in non-Hispanic white men, respectively. Although not associated with risk among non-Hispanic white men, BMI was positively associated with an increase in risk among African American men (BMI, American race increased from 28% (HR, 1.28 [95% CI, 0.91-1.80]) among men with BMI less than 25 to 103% (HR, 2.03 [95% CI, 1.38-2.98]) among African American men with BMI at least 35 (P for trend = .03). Body mass index was inversely associated with low-grade prostate cancer risk within non-Hispanic white men (BMI, American men (BMI, American men, although the increase may be larger within African American men, albeit the racial interaction was not statistically significant (BMI, Obesity is more strongly associated with increased prostate cancer risk among African American than non-Hispanic white men and reducing obesity among African American men could reduce the racial disparity in cancer incidence. Additional research is needed to elucidate the mechanisms underlying the differential effects of obesity in African American and non-Hispanic white men.

Hybrid inverse design method for nonlifting bodies in incompressible flow

CSIR Research Space (South Africa)

Broughton, BA

2006-11-01

Full Text Available A methodology for the inverse design of non-lifting axisymmetric bodies in compressible flow is presented. In this method, an inverse design approach based on conformal mapping is used to design a set of airfoils in isolation. These airfoils...

Core flow inversion tested with numerical dynamo models

Science.gov (United States)

Rau, Steffen; Christensen, Ulrich; Jackson, Andrew; Wicht, Johannes

2000-05-01

We test inversion methods of geomagnetic secular variation data for the pattern of fluid flow near the surface of the core with synthetic data. These are taken from self-consistent 3-D models of convection-driven magnetohydrodynamic dynamos in rotating spherical shells, which generate dipole-dominated magnetic fields with an Earth-like morphology. We find that the frozen-flux approximation, which is fundamental to all inversion schemes, is satisfied to a fair degree in the models. In order to alleviate the non-uniqueness of the inversion, usually a priori conditions are imposed on the flow; for example, it is required to be purely toroidal or geostrophic. Either condition is nearly satisfied by our model flows near the outer surface. However, most of the surface velocity field lies in the nullspace of the inversion problem. Nonetheless, the a priori constraints reduce the nullspace, and by inverting the magnetic data with either one of them we recover a significant part of the flow. With the geostrophic condition the correlation coefficient between the inverted and the true velocity field can reach values of up to 0.65, depending on the choice of the damping parameter. The correlation is significant at the 95 per cent level for most spherical harmonic degrees up to l=26. However, it degrades substantially, even at long wavelengths, when we truncate the magnetic data sets to l currents, similar to those seen in core-flow models derived from geomagnetic data, occur in the equatorial region. However, the true flow does not contain this flow component. The results suggest that some meaningful information on the core-flow pattern can be retrieved from secular variation data, but also that the limited resolution of the magnetic core field could produce serious artefacts.

Optimization for nonlinear inverse problem

International Nuclear Information System (INIS)

Boyadzhiev, G.; Brandmayr, E.; Pinat, T.; Panza, G.F.

2007-06-01

The nonlinear inversion of geophysical data in general does not yield a unique solution, but a single model, representing the investigated field, is preferred for an easy geological interpretation of the observations. The analyzed region is constituted by a number of sub-regions where the multi-valued nonlinear inversion is applied, which leads to a multi-valued solution. Therefore, combining the values of the solution in each sub-region, many acceptable models are obtained for the entire region and this complicates the geological interpretation of geophysical investigations. In this paper are presented new methodologies, capable to select one model, among all acceptable ones, that satisfies different criteria of smoothness in the explored space of solutions. In this work we focus on the non-linear inversion of surface waves dispersion curves, which gives structural models of shear-wave velocity versus depth, but the basic concepts have a general validity. (author)

Workshop on Non-Associative & Non-Commutative Algebra and Operator Theory

CERN Document Server

Molina, Mercedes

2016-01-01

Presenting the collaborations of over thirty international experts in the latest developments in pure and applied mathematics, this volume serves as an anthology of research with a common basis in algebra, functional analysis and their applications. Special attention is devoted to non-commutative algebras, non-associative algebras, operator theory and ring and module theory. These themes are relevant in research and development in coding theory, cryptography and quantum mechanics. The topics in this volume were presented at the Workshop on Non-Associative & Non-Commutative Algebra and Operator Theory, held May 23—25, 2014 at Cheikh Anta Diop University in Dakar, Senegal in honor of Professor Amin Kaidi. The workshop was hosted by the university's Laboratory of Algebra, Cryptology, Algebraic Geometry and Applications, in cooperation with the University of Almería and the University of Málaga. Dr. Kaidi's work focuses on non-associative rings and algebras, operator theory and functional analysis, and he...

Solution accelerators for large scale 3D electromagnetic inverse problems

International Nuclear Information System (INIS)

Newman, Gregory A.; Boggs, Paul T.

2004-01-01

We provide a framework for preconditioning nonlinear 3D electromagnetic inverse scattering problems using nonlinear conjugate gradient (NLCG) and limited memory (LM) quasi-Newton methods. Key to our approach is the use of an approximate adjoint method that allows for an economical approximation of the Hessian that is updated at each inversion iteration. Using this approximate Hessian as a preconditoner, we show that the preconditioned NLCG iteration converges significantly faster than the non-preconditioned iteration, as well as converging to a data misfit level below that observed for the non-preconditioned method. Similar conclusions are also observed for the LM iteration; preconditioned with the approximate Hessian, the LM iteration converges faster than the non-preconditioned version. At this time, however, we see little difference between the convergence performance of the preconditioned LM scheme and the preconditioned NLCG scheme. A possible reason for this outcome is the behavior of the line search within the LM iteration. It was anticipated that, near convergence, a step size of one would be approached, but what was observed, instead, were step lengths that were nowhere near one. We provide some insights into the reasons for this behavior and suggest further research that may improve the performance of the LM methods

Inverse scattering transform and soliton solutions for square matrix nonlinear Schrödinger equations with non-zero boundary conditions

Science.gov (United States)

Prinari, Barbara; Demontis, Francesco; Li, Sitai; Horikis, Theodoros P.

2018-04-01

The inverse scattering transform (IST) with non-zero boundary conditions at infinity is developed for an m × m matrix nonlinear Schrödinger-type equation which, in the case m = 2, has been proposed as a model to describe hyperfine spin F = 1 spinor Bose-Einstein condensates with either repulsive interatomic interactions and anti-ferromagnetic spin-exchange interactions (self-defocusing case), or attractive interatomic interactions and ferromagnetic spin-exchange interactions (self-focusing case). The IST for this system was first presented by Ieda et al. (2007) , using a different approach. In our formulation, both the direct and the inverse problems are posed in terms of a suitable uniformization variable which allows to develop the IST on the standard complex plane, instead of a two-sheeted Riemann surface or the cut plane with discontinuities along the cuts. Analyticity of the scattering eigenfunctions and scattering data, symmetries, properties of the discrete spectrum, and asymptotics are derived. The inverse problem is posed as a Riemann-Hilbert problem for the eigenfunctions, and the reconstruction formula of the potential in terms of eigenfunctions and scattering data is provided. In addition, the general behavior of the soliton solutions is analyzed in detail in the 2 × 2 self-focusing case, including some special solutions not previously discussed in the literature.

Inverse Higgs effect in nonlinear realizations

International Nuclear Information System (INIS)

Ivanov, E.A.; Ogievetskij, V.I.

1975-01-01

In theories with nonlinearly realized symmetry it is possible in a number of cases to eliminate some initial Goldstone and gauge fields by means of putting appropriate Cartan forms equal to zero. This is called the inverse Higgs phenomenon. We give a general treatment of the inverse Higgs phenomenon for gauge and space-time symmetries and consider four instructive examples which are the elimination of unessential gauge fields in chiral symmetry and in non-linearly realized supersymmetry and also the elimination of unessential Goldstone fields in the spontaneously broken conformal and projective symmetries

Factors associated with routine childhood vaccine uptake and reasons for non-vaccination in India: 1998-2008.

Science.gov (United States)

Francis, Mark Rohit; Nohynek, Hanna; Larson, Heidi; Balraj, Vinohar; Mohan, Venkata Raghava; Kang, Gagandeep; Nuorti, J Pekka

2017-08-24

Despite almost three decades of the Universal Immunization Program in India, a little more than half the children aged 12-23months receive the full schedule of routine vaccinations. We examined socio-demographic factors associated with partial-vaccination and non-vaccination and the reasons for non-vaccination among Indian children during 1998 and 2008. Data from three consecutive, nationally-representative, District Level Household and Facility Surveys (1998-99, 2002-04 and 2007-08) were pooled. Multinomial logistic regression was used to identify individual and household level socio-demographic variables associated with the child's vaccination status. The mother's reported reasons for non-vaccination were analyzed qualitatively, adapting from a previously published framework. The pooled dataset contained information on 178,473 children 12-23months of age; 53%, 32% and 15% were fully vaccinated, partially vaccinated and unvaccinated respectively. Compared with the 1998-1999 survey, children in the 2007-2008 survey were less likely to be unvaccinated (Adjusted Prevalence Odds Ratio (aPOR): 0.92, 95%CI=0.86-0.98) but more likely to be partially vaccinated (aPOR: 1.58, 95%CI=1.52-1.65). Vaccination status was inversely associated with female gender, Muslim religion, lower caste, urban residence and maternal characteristics such as lower educational attainment, non-institutional delivery, fewer antenatal care visits and non-receipt of maternal tetanus vaccination. The mother's reported reasons for non-vaccination indicated gaps in awareness, acceptance and affordability (financial and non-financial costs) related to routine vaccinations. Persisting socio-demographic disparities related to partial-vaccination and non-vaccination were associated with important childhood, maternal and household characteristics. Further research investigating the causal pathways through which maternal and social characteristics influence decision-making for childhood vaccinations is

Gauge equivalence of σ models with non-compact Grassmannian manifolds

International Nuclear Information System (INIS)

Kundu, A.

1986-01-01

The gauge equivalence (GE) of σ models associated with non-compact Grassmannian manifolds is investigated with emphasis on the necessary restrictions for the choice of gauge elements in such cases. The importance of GE in solving a non-linear system with the help of inverse scattering data of its gauge related counterpart is demonstrated. The gauge relations between generalised Landau-Lifshitz (LL) and non-linear Schroedinger (NLS) type equations and also between non-linear σ models and generalised 'sine-sinh-Gordon' equations for non-compact SU(p,q)/S(U(u,v) x U(s,t)) manifolds are established. Using H-gauge invariance of LL the GE is extended to some higher-order specific non-linear systems. The gauge connection among various LL and NLS equations are schematically represented. Along with the recovery of earlier results important new results, some with significant non-compact structures, are discovered. (author)

Circulating Irisin Concentrations Are Associated with a Favourable Lipid Profile in the General Population.

Directory of Open Access Journals (Sweden)

Simon Oelmann

Full Text Available Irisin is a myokine, which is mainly inversely associated with the risk for non-communicable diseases. Irisin improves cellular energy metabolism by uncoupling the mitochondrial respiratory chain resulting in increased energy expenditure using lipids. To date potential associations between irisin concentration and lipid profile are poorly understood. Therefore, this investigation aimed to evaluate potential associations between irisin and lipid levels in the general population.Data of 430 men and 537 women from the population-based Study of Health in Pomerania (SHIP-TREND with available irisin and lipid concentrations were used. Analyses of variance, linear and logistic regression models adjusted for age, HBA1c, waist circumference, physical activity, smoking, alcohol consumption, systolic blood pressure, ALAT were calculated.We detected significantly inverse associations between irisin and circulating levels of total [beta coefficient 0.21 (standard error 0.08, p = 0.01], low-density cholesterol [-0.16 (0.07, p = 0.03] and triglycerides [-0.17 (0.08, p = 0.02] for men. Females without lipid lowering medication had an inverse association between irisin and total cholesterol [-0.12 (0.06, p = 0.05]. Further, male subjects with irisin concentrations in the third tertile had an increased odds for elevated low-density cholesterol [odds ratio 1.96 (95% confidence interval 1.07-3.48, p = 0.03 and triglyceride [1.95 (1.09-3.47, p = 0.02] levels, even after exclusion of subjects with lipid lowering medication. In addition, our data revealed an annual rhythm of serum irisin levels with peak levels arise in winter and summer months.This is the first investigation to report a significant association between circulating irisin and a favourable lipid profile in the general population. This may infer that higher irisin concentrations are associated with a reduced risk for non-communicable diseases.

Connection between Dirac and matrix Schroedinger inverse-scattering transforms

International Nuclear Information System (INIS)

Jaulent, M.; Leon, J.J.P.

1978-01-01

The connection between two applications of the inverse scattering method for solving nonlinear equations is established. The inverse method associated with the massive Dirac system (D) : (iσ 3 d/dx - i q 3 σ 1 - q 1 σ 2 + mσ 2 )Y = epsilonY is rediscovered from the inverse method associated with the 2 x 2 matrix Schroedinger equation (S) : Ysub(xx) + (k 2 -Q)Y = 0. Here Q obeys a nonlinear constraint equivalent to a linear constraint on the reflection coefficient for (S). (author)

Recreational physical activity is inversely associated with asymptomatic gallstones in adult Mexican women.

Science.gov (United States)

Henao-Morán, Santiago; Denova-Gutiérrez, Edgar; Morán, Segundo; Duque, Ximena; Gallegos-Carrillo, Katia; Macías, Nayeli; Salmerón, Jorge

2014-01-01

Epidemiologic research suggests that physical activity (PA) reduces the risk of chronic diseases including gallstones. This study explores the association between recreational physical activity (RPA) and risk of asymptomatic gallstones (AG) in adult Mexican women. We performed a cross-sectional analysis of women from the Health Workers Cohort Study. The study population included Mexican women aged 17-94 years, with no history of gallstone (GS) or cholecystectomy. A self-administered questionnaire was used to collect information on weight change, gynecological health history, cholesterol-lowering medications and diuretics, history of diabetes mellitus type 2 (DM2), PA and diet. PA was calculated in minutes/day, minutes/week and Metabolic Equivalents (METs)/week. Gallstone diagnosis was performed using real-time ultrasonography. The association between RPA and risk of AG was evaluated using multivariate logistic regression models. Results. Of the 4,953 women involved in the study, 12.3% were diagnosed with AG. The participants with AG were significantly older, had a higher body mass index, and had a higher prevalence of DM2 than those without AG. The participants with > 30 min/day of RPA had lower odds of AG (OR = 0.80; 95% CI: 0.65-0.97; P = 0.03), regardless of other known risk factors for gallstone disease. Furthermore, we observed an inverse relationship between RPA time and AG risk, especially in women doing more than 150 min a week of RPA (OR = 0.76; 95%CI: 0.61- 0.95; P = 0.02). These findings support the hypothesis that RPA may protect against AG, although further prospective investigations are needed to confirm this association.

Interplay of Nitrogen-Atom Inversion and Conformational Inversion in Enantiomerization of 1H-1-Benzazepines.

Science.gov (United States)

Ramig, Keith; Subramaniam, Gopal; Karimi, Sasan; Szalda, David J; Ko, Allen; Lam, Aaron; Li, Jeffrey; Coaderaj, Ani; Cavdar, Leyla; Bogdan, Lukasz; Kwon, Kitae; Greer, Edyta M

2016-04-15

A series of 2,4-disubstituted 1H-1-benzazepines, 2a-d, 4, and 6, were studied, varying both the substituents at C2 and C4 and at the nitrogen atom. The conformational inversion (ring-flip) and nitrogen-atom inversion (N-inversion) energetics were studied by variable-temperature NMR spectroscopy and computations. The steric bulk of the nitrogen-atom substituent was found to affect both the conformation of the azepine ring and the geometry around the nitrogen atom. Also affected were the Gibbs free energy barriers for the ring-flip and the N-inversion. When the nitrogen-atom substituent was alkyl, as in 2a-c, the geometry of the nitrogen atom was nearly planar and the azepine ring was highly puckered; the result was a relatively high-energy barrier to ring-flip and a low barrier to N-inversion. Conversely, when the nitrogen-atom substituent was a hydrogen atom, as in 2d, 4, and 6, the nitrogen atom was significantly pyramidalized and the azepine ring was less puckered; the result here was a relatively high energy barrier to N-inversion and a low barrier to ring-flip. In these N-unsubstituted compounds, it was found computationally that the lowest-energy stereodynamic process was ring-flip coupled with N-inversion, as N-inversion alone had a much higher energy barrier.

Inverse vs. forward breast IMRT planning

International Nuclear Information System (INIS)

Mihai, Alina; Rakovitch, Eileen; Sixel, Katharina; Woo, Tony; Cardoso, Marlene; Bell, Chris; Ruschin, Mark; Pignol, Jean-Philippe

2005-01-01

Breast intensity-modulated radiation therapy (IMRT) improves dose distribution homogeneity within the whole breast. Previous publications report the use of inverse or forward dose optimization algorithms. Because the inverse technique is not widely available in commercial treatment planning systems, it is important to compare the 2 algorithms. The goal of this work is to compare them on a prospective cohort of 30 patients. Dose distributions were evaluated on differential dose-volume histograms using the volumes receiving more than 105% (V 105 ) and 110% (V 110 ) of the prescribed dose, and on the maximum dose (D max ) or hot spot and the sagittal dose gradient (SDG) being the gradient between the dose on inframammary crease and the dose prescribed. The data were analyzed using Wilcoxon signed rank test. The inverse planning significantly improves the V 105 (mean value 9.7% vs. 14.5%, p = 0.002), and the V 110 (mean value 1.4% vs. 3.2%, p = 0.006). However, the SDG is not statistically significantly different for either algorithm. Looking at the potential impact on skin acute reaction, although there is a significant reduction of V 110 using an inverse algorithm, it is unlikely this 1.6% volume reduction will present a significant clinical advantage over a forward algorithm. Both algorithms are equivalent in removing the hot spots on the inframammary fold, where acute skin reactions occur more frequently using a conventional wedge technique. Based on these results, we recommend that both forward and inverse algorithms should be considered for breast IMRT planning

Breast-cancer-associated metastasis is significantly increased in a model of autoimmune arthritis.

Science.gov (United States)

Das Roy, Lopamudra; Pathangey, Latha B; Tinder, Teresa L; Schettini, Jorge L; Gruber, Helen E; Mukherjee, Pinku

2009-01-01

Sites of chronic inflammation are often associated with the establishment and growth of various malignancies including breast cancer. A common inflammatory condition in humans is autoimmune arthritis (AA) that causes inflammation and deformity of the joints. Other systemic effects associated with arthritis include increased cellular infiltration and inflammation of the lungs. Several studies have reported statistically significant risk ratios between AA and breast cancer. Despite this knowledge, available for a decade, it has never been questioned if the site of chronic inflammation linked to AA creates a milieu that attracts tumor cells to home and grow in the inflamed bones and lungs which are frequent sites of breast cancer metastasis. To determine if chronic inflammation induced by autoimmune arthritis contributes to increased breast cancer-associated metastasis, we generated mammary gland tumors in SKG mice that were genetically prone to develop AA. Two breast cancer cell lines, one highly metastatic (4T1) and the other non-metastatic (TUBO) were used to generate the tumors in the mammary fat pad. Lung and bone metastasis and the associated inflammatory milieu were evaluated in the arthritic versus the non-arthritic mice. We report a three-fold increase in lung metastasis and a significant increase in the incidence of bone metastasis in the pro-arthritic and arthritic mice compared to non-arthritic control mice. We also report that the metastatic breast cancer cells augment the severity of arthritis resulting in a vicious cycle that increases both bone destruction and metastasis. Enhanced neutrophilic and granulocytic infiltration in lungs and bone of the pro-arthritic and arthritic mice and subsequent increase in circulating levels of proinflammatory cytokines, such as macrophage colony stimulating factor (M-CSF), interleukin-17 (IL-17), interleukin-6 (IL-6), vascular endothelial growth factor (VEGF), and tumor necrosis factor-alpha (TNF-alpha) may contribute

Breast cancer-associated metastasis is significantly increased in a model of autoimmune arthritis

Science.gov (United States)

Das Roy, Lopamudra; Pathangey, Latha B; Tinder, Teresa L; Schettini, Jorge L; Gruber, Helen E; Mukherjee, Pinku

2009-01-01

Introduction Sites of chronic inflammation are often associated with the establishment and growth of various malignancies including breast cancer. A common inflammatory condition in humans is autoimmune arthritis (AA) that causes inflammation and deformity of the joints. Other systemic effects associated with arthritis include increased cellular infiltration and inflammation of the lungs. Several studies have reported statistically significant risk ratios between AA and breast cancer. Despite this knowledge, available for a decade, it has never been questioned if the site of chronic inflammation linked to AA creates a milieu that attracts tumor cells to home and grow in the inflamed bones and lungs which are frequent sites of breast cancer metastasis. Methods To determine if chronic inflammation induced by autoimmune arthritis contributes to increased breast cancer-associated metastasis, we generated mammary gland tumors in SKG mice that were genetically prone to develop AA. Two breast cancer cell lines, one highly metastatic (4T1) and the other non-metastatic (TUBO) were used to generate the tumors in the mammary fat pad. Lung and bone metastasis and the associated inflammatory milieu were evaluated in the arthritic versus the non-arthritic mice. Results We report a three-fold increase in lung metastasis and a significant increase in the incidence of bone metastasis in the pro-arthritic and arthritic mice compared to non-arthritic control mice. We also report that the metastatic breast cancer cells augment the severity of arthritis resulting in a vicious cycle that increases both bone destruction and metastasis. Enhanced neutrophilic and granulocytic infiltration in lungs and bone of the pro-arthritic and arthritic mice and subsequent increase in circulating levels of proinflammatory cytokines, such as macrophage colony stimulating factor (M-CSF), interleukin-17 (IL-17), interleukin-6 (IL-6), vascular endothelial growth factor (VEGF), and tumor necrosis factor

On the connection between the inverse transform method and the exact quantum eigenstates

International Nuclear Information System (INIS)

Honerkamp, J.; Weber, P.; Wiesler, A.

1979-01-01

The 'inverse scattering transformation', which has been used to solve certain nonlinear field theories classically, is discussed in the context of the quantized version of these theories. In particular the non-linear Schroedinger equation and the massive Thirring model are considered. It is found that certain Jost functions of the associated scattering problem lead already, in quantizing the theory, to creation operators for the exact eigenstates of the corresponding Hamiltonians. (Auth.)

Serum 25(OHD is inversely associated with metabolic syndrome risk profile among urban middle-aged Chinese population

Directory of Open Access Journals (Sweden)

Yin Xiao

2012-09-01

Full Text Available Abstract Background Vitamin D deficiency is associated with a variety of chronic metabolic diseases. Limited evidence regarding vitamin D deficiency exists within the Chinese population. The present study aims to examine the association between serum vitamin D concentrations and cardiometabolic risk factors in the young and middle-aged, urban Chinese population Methods The cross-sectional relationships between serum 25-hydroxyvitamin D [25(OHD] concentrations and indices of adiposity and cardiometabolic risk factors (e.g., body mass index, waist circumference, fasting plasma glucose, etc. were evaluated in 601 non-diabetic adults. Result Vitamin D deficiency or insufficiency was present in 66% of the tested population, and serum 25(OHD levels were lower in patients who were overweight/obese or suffered metabolic syndrome when compared to individuals of healthy weight without metabolic syndrome (24.08 ± 8.08 vs 31.70 ± 11.77 ng/ml, 21.52 ± 6.9 vs 31.74 ± 10.21 ng/ml respectively. 25(OHD was inversely associated with waist circumference, fasting glucose, fasting insulin, triglycerides and LDL-cholesterol, and it was positively associated with HDL-cholesterol in a multivariable-adjusted regression model. Conclusion Vitamin D deficiency is common in the young and middle-aged, urban Chinese population, with high prevalence in overweight/obese individuals and patients with metabolic syndrome. Low vitamin D concentration was associated with indices of adiposity and cardiometabolic risk factors. Further studies are warranted to elucidate the cause-effect relation between vitamin D status, obesity and related metabolic disorders. Trial registration Current Controlled Trials (ISRCTN21527585

Two non-synonymous markers in PTPN21, identified by genome-wide association study data-mining and replication, are associated with schizophrenia.

LENUS (Irish Health Repository)

Chen, Jingchun

2011-09-01

We conducted data-mining analyses of genome wide association (GWA) studies of the CATIE and MGS-GAIN datasets, and found 13 markers in the two physically linked genes, PTPN21 and EML5, showing nominally significant association with schizophrenia. Linkage disequilibrium (LD) analysis indicated that all 7 markers from PTPN21 shared high LD (r(2)>0.8), including rs2274736 and rs2401751, the two non-synonymous markers with the most significant association signals (rs2401751, P=1.10 × 10(-3) and rs2274736, P=1.21 × 10(-3)). In a meta-analysis of all 13 replication datasets with a total of 13,940 subjects, we found that the two non-synonymous markers are significantly associated with schizophrenia (rs2274736, OR=0.92, 95% CI: 0.86-0.97, P=5.45 × 10(-3) and rs2401751, OR=0.92, 95% CI: 0.86-0.97, P=5.29 × 10(-3)). One SNP (rs7147796) in EML5 is also significantly associated with the disease (OR=1.08, 95% CI: 1.02-1.14, P=6.43 × 10(-3)). These 3 markers remain significant after Bonferroni correction. Furthermore, haplotype conditioned analyses indicated that the association signals observed between rs2274736\\/rs2401751 and rs7147796 are statistically independent. Given the results that 2 non-synonymous markers in PTPN21 are associated with schizophrenia, further investigation of this locus is warranted.

Wake Vortex Inverse Model User's Guide

Science.gov (United States)

Lai, David; Delisi, Donald

2008-01-01

NorthWest Research Associates (NWRA) has developed an inverse model for inverting landing aircraft vortex data. The data used for the inversion are the time evolution of the lateral transport position and vertical position of both the port and starboard vortices. The inverse model performs iterative forward model runs using various estimates of vortex parameters, vertical crosswind profiles, and vortex circulation as a function of wake age. Forward model predictions of lateral transport and altitude are then compared with the observed data. Differences between the data and model predictions guide the choice of vortex parameter values, crosswind profile and circulation evolution in the next iteration. Iterations are performed until a user-defined criterion is satisfied. Currently, the inverse model is set to stop when the improvement in the rms deviation between the data and model predictions is less than 1 percent for two consecutive iterations. The forward model used in this inverse model is a modified version of the Shear-APA model. A detailed description of this forward model, the inverse model, and its validation are presented in a different report (Lai, Mellman, Robins, and Delisi, 2007). This document is a User's Guide for the Wake Vortex Inverse Model. Section 2 presents an overview of the inverse model program. Execution of the inverse model is described in Section 3. When executing the inverse model, a user is requested to provide the name of an input file which contains the inverse model parameters, the various datasets, and directories needed for the inversion. A detailed description of the list of parameters in the inversion input file is presented in Section 4. A user has an option to save the inversion results of each lidar track in a mat-file (a condensed data file in Matlab format). These saved mat-files can be used for post-inversion analysis. A description of the contents of the saved files is given in Section 5. An example of an inversion input

2D acoustic-elastic coupled waveform inversion in the Laplace domain

KAUST Repository

Bae, Hoseuk

2010-04-01

Although waveform inversion has been intensively studied in an effort to properly delineate the Earth\\'s structures since the early 1980s, most of the time- and frequency-domain waveform inversion algorithms still have critical limitations in their applications to field data. This may be attributed to the highly non-linear objective function and the unreliable low-frequency components. To overcome the weaknesses of conventional waveform inversion algorithms, the acoustic Laplace-domain waveform inversion has been proposed. The Laplace-domain waveform inversion has been known to provide a long-wavelength velocity model even for field data, which may be because it employs the zero-frequency component of the damped wavefield and a well-behaved logarithmic objective function. However, its applications have been confined to 2D acoustic media.We extend the Laplace-domain waveform inversion algorithm to a 2D acoustic-elastic coupled medium, which is encountered in marine exploration environments. In 2D acoustic-elastic coupled media, the Laplace-domain pressures behave differently from those of 2D acoustic media, although the overall features are similar to each other. The main differences are that the pressure wavefields for acoustic-elastic coupled media show negative values even for simple geological structures unlike in acoustic media, when the Laplace damping constant is small and the water depth is shallow. The negative values may result from more complicated wave propagation in elastic media and at fluid-solid interfaces.Our Laplace-domain waveform inversion algorithm is also based on the finite-element method and logarithmic wavefields. To compute gradient direction, we apply the back-propagation technique. Under the assumption that density is fixed, P- and S-wave velocity models are inverted from the pressure data. We applied our inversion algorithm to the SEG/EAGE salt model and the numerical results showed that the Laplace-domain waveform inversion

Group inverses of M-matrices and their applications

CERN Document Server

Kirkland, Stephen J

2013-01-01

Group inverses for singular M-matrices are useful tools not only in matrix analysis, but also in the analysis of stochastic processes, graph theory, electrical networks, and demographic models. Group Inverses of M-Matrices and Their Applications highlights the importance and utility of the group inverses of M-matrices in several application areas. After introducing sample problems associated with Leslie matrices and stochastic matrices, the authors develop the basic algebraic and spectral properties of the group inverse of a general matrix. They then derive formulas for derivatives of matrix f

Interferometric full-waveform inversion of time-lapse data

KAUST Repository

Sinha, Mrinal

2017-08-17

One of the key challenges associated with time-lapse surveys is ensuring the repeatability between the baseline and monitor surveys. Non-repeatability between the surveys is caused by varying environmental conditions over the course of different surveys. To overcome this challenge, we propose the use of interferometric full waveform inversion (IFWI) for inverting the velocity model from data recorded by baseline and monitor surveys. A known reflector is used as the reference reflector for IFWI, and the data are naturally redatumed to this reference reflector using natural reflections as the redatuming operator. This natural redatuming mitigates the artifacts introduced by the repeatability errors that originate above the reference reflector.

Non-contrast MRA using an inflow-enhanced, inversion recovery SSFP technique in pediatric abdominal imaging

International Nuclear Information System (INIS)

Serai, Suraj; Towbin, Alexander J.; Podberesky, Daniel J.

2012-01-01

Abdominal contrast-enhanced MR angiography (CE-MRA) is routinely performed in children. CE-MRA is challenging in children because of patient motion, difficulty in obtaining intravenous access, and the inability of young patients to perform a breath-hold during imaging. The combination of pediatric-specific difficulties in imaging and the safety concerns regarding the risk of gadolinium-based contrast agents in patients with impaired renal function has renewed interest in the use of non-contrast (NC) MRA techniques. At our institution, we have optimized 3-D NC-MRA techniques for abdominal imaging. The purpose of this work is to demonstrate the utility of an inflow-enhanced, inversion recovery balanced steady-state free precession-based (b-SSFP) NC-MRA technique. (orig.)

Inverse photoemission

International Nuclear Information System (INIS)

Namatame, Hirofumi; Taniguchi, Masaki

1994-01-01

Photoelectron spectroscopy is regarded as the most powerful means since it can measure almost perfectly the occupied electron state. On the other hand, inverse photoelectron spectroscopy is the technique for measuring unoccupied electron state by using the inverse process of photoelectron spectroscopy, and in principle, the similar experiment to photoelectron spectroscopy becomes feasible. The development of the experimental technology for inverse photoelectron spectroscopy has been carried out energetically by many research groups so far. At present, the heightening of resolution of inverse photoelectron spectroscopy, the development of inverse photoelectron spectroscope in which light energy is variable and so on are carried out. But the inverse photoelectron spectroscope for vacuum ultraviolet region is not on the market. In this report, the principle of inverse photoelectron spectroscopy and the present state of the spectroscope are described, and the direction of the development hereafter is groped. As the experimental equipment, electron guns, light detectors and so on are explained. As the examples of the experiment, the inverse photoelectron spectroscopy of semimagnetic semiconductors and resonance inverse photoelectron spectroscopy are reported. (K.I.)

Association between simian virus 40 and non-Hodgkin lymphoma

Science.gov (United States)

Vilchez, Regis A.; Madden, Charles R.; Kozinetz, Claudia A.; Halvorson, Steven J.; White, Zoe S.; Jorgensen, Jeffrey L.; Finch, Chris J.; Butel, Janet S.

2002-01-01

BACKGROUND: Non-Hodgkin lymphoma has increased in frequency over the past 30 years, and is a common cancer in HIV-1-infected patients. Although no definite risk factors have emerged, a viral cause has been postulated. Polyomaviruses are known to infect human beings and to induce tumours in laboratory animals. We aimed to identify which one of the three polyomaviruses able to infect human beings (simian virus 40 [SV40], JC virus, and BK virus) was associated with non-Hodgkin lymphoma. METHODS: We analysed systemic non-Hodgkin lymphoma from 76 HIV-1-infected and 78 HIV-1-uninfected patients, and non-malignant lymphoid samples from 79 HIV-1-positive and 107 HIV-1-negative patients without tumours; 54 colon and breast carcinoma samples served as cancer controls. We used PCR followed by Southern blot hybridisation and DNA sequence analysis to detect DNAs of polyomaviruses and herpesviruses. FINDINGS: Polyomavirus T antigen sequences, all of which were SV40-specific, were detected in 64 (42%) of 154 non-Hodgkin lymphomas, none of 186 non-malignant lymphoid samples, and none of 54 control cancers. This difference was similar for HIV-1-infected patients and HIV-1-uninfected patients alike. Few tumours were positive for both SV40 and Epstein-Barr virus. Human herpesvirus type 8 was not detected. SV40 sequences were found most frequently in diffuse large B-cell and follicular-type lymphomas. INTERPRETATION: SV40 is significantly associated with some types of non-Hodgkin lymphoma. These results add lymphomas to the types of human cancers associated with SV40.

Parameter estimation and inverse problems

CERN Document Server

Aster, Richard C; Thurber, Clifford H

2005-01-01

Parameter Estimation and Inverse Problems primarily serves as a textbook for advanced undergraduate and introductory graduate courses. Class notes have been developed and reside on the World Wide Web for faciliting use and feedback by teaching colleagues. The authors'' treatment promotes an understanding of fundamental and practical issus associated with parameter fitting and inverse problems including basic theory of inverse problems, statistical issues, computational issues, and an understanding of how to analyze the success and limitations of solutions to these probles. The text is also a practical resource for general students and professional researchers, where techniques and concepts can be readily picked up on a chapter-by-chapter basis.Parameter Estimation and Inverse Problems is structured around a course at New Mexico Tech and is designed to be accessible to typical graduate students in the physical sciences who may not have an extensive mathematical background. It is accompanied by a Web site that...

An inverse method for non linear ablative thermics with experimentation of automatic differentiation

Energy Technology Data Exchange (ETDEWEB)

Alestra, S [Simulation Information Technology and Systems Engineering, EADS IW Toulouse (France); Collinet, J [Re-entry Systems and Technologies, EADS ASTRIUM ST, Les Mureaux (France); Dubois, F [Professor of Applied Mathematics, Conservatoire National des Arts et Metiers Paris (France)], E-mail: stephane.alestra@eads.net, E-mail: jean.collinet@astrium.eads.net, E-mail: fdubois@cnam.fr

2008-11-01

Thermal Protection System is a key element for atmospheric re-entry missions of aerospace vehicles. The high level of heat fluxes encountered in such missions has a direct effect on mass balance of the heat shield. Consequently, the identification of heat fluxes is of great industrial interest but is in flight only available by indirect methods based on temperature measurements. This paper is concerned with inverse analyses of highly evolutive heat fluxes. An inverse problem is used to estimate transient surface heat fluxes (convection coefficient), for degradable thermal material (ablation and pyrolysis), by using time domain temperature measurements on thermal protection. The inverse problem is formulated as a minimization problem involving an objective functional, through an optimization loop. An optimal control formulation (Lagrangian, adjoint and gradient steepest descent method combined with quasi-Newton method computations) is then developed and applied, using Monopyro, a transient one-dimensional thermal model with one moving boundary (ablative surface) that has been developed since many years by ASTRIUM-ST. To compute numerically the adjoint and gradient quantities, for the inverse problem in heat convection coefficient, we have used both an analytical manual differentiation and an Automatic Differentiation (AD) engine tool, Tapenade, developed at INRIA Sophia-Antipolis by the TROPICS team. Several validation test cases, using synthetic temperature measurements are carried out, by applying the results of the inverse method with minimization algorithm. Accurate results of identification on high fluxes test cases, and good agreement for temperatures restitutions, are obtained, without and with ablation and pyrolysis, using bad fluxes initial guesses. First encouraging results with an automatic differentiation procedure are also presented in this paper.

Polymorphism in COX-2 modifies the inverse association between Helicobacter pylori seropositivity and esophageal squamous cell carcinoma risk in Taiwan: a case control study.

Science.gov (United States)

Hu, Huang-Ming; Kuo, Chao-Hung; Lee, Chien-Hung; Wu, I-Chen; Lee, Ka-Wo; Lee, Jang-Ming; Goan, Yih-Gang; Chou, Shah-Hwa; Kao, Ein-Long; Wu, Ming-Tsang; Wu, Deng-Chyang

2009-05-23

Overexpression of Cyclooxygenase-2 (COX-2) was observed in many types of cancers, including esophageal squamous cell carcinoma (ESCC). One functional SNP, COX-2 -1195G/A, has been reported to mediate susceptibility of ESCC in Chinese populations. In our previous study, the presence of Helicobacter pylori (H. pylori) was found to play a protective role in development of ESCC. The interaction of COX-2 and H. pylori in gastric cancer was well investigated. However, literature on their interaction in ESCC risk is scarce. The purpose of this study was to evaluate the association and interaction between COX-2 single nucleotide polymorphism (SNP), H. pylori infection and the risk of developing ESCC. One hundred and eighty patients with ESCC and 194 controls were enrolled in this study. Personal data regarding related risk factors, including alcohol consumption, smoking habits and betel quid chewing, were collected via questionnaire. Genotypes of the COX-2 -1195 polymorphism were determined by PCR-based restriction fragment length polymorphism. H. pylori seropositivity was defined by immunochromatographic screening test. Data was analyzed by chi-squared tests and polytomous logistics regression. In analysis adjusting for the covariates and confounders, H. pylori seropositivity was found to be inversely association with the ESCC development (adjusted OR: 0.5, 95% CI: 0.3 - 0.9). COX-2 -1195 AA homozygous was associated with an increased risk of contracting ESCC in comparison with the non-AA group, especially among patients with H. pylori seronegative (adjusted OR ratio: 2.9, 95% CI: 1.2 - 7.3). The effect was strengthened among patients with lower third ESCC (adjusted OR ratio: 6.9, 95% CI 2.1 - 22.5). Besides, H. pylori seropositivity conveyed a notably inverse effect among patients with COX-2 AA polymorphism (AOR ratio: 0.3, 95% CI: 0.1 - 0.9), and the effect was observed to be enhanced for the lower third ESCC patients (AOR ratio: 0.09, 95% CI: 0.02 - 0.47, p for

Inverse Kinematics of a Humanoid Robot with Non-Spherical Hip: A Hybrid Algorithm Approach

Directory of Open Access Journals (Sweden)

Rafael Cisneros Limón

2013-04-01

Full Text Available This paper describes an approach to solve the inverse kinematics problem of humanoid robots whose construction shows a small but non negligible offset at the hip which prevents any purely analytical solution to be developed. Knowing that a purely numerical solution is not feasible due to variable efficiency problems, the proposed one first neglects the offset presence in order to obtain an approximate “solution” by means of an analytical algorithm based on screw theory, and then uses it as the initial condition of a numerical refining procedure based on the Levenberg-Marquardt algorithm. In this way, few iterations are needed for any specified attitude, making it possible to implement the algorithm for real-time applications. As a way to show the algorithm's implementation, one case of study is considered throughout the paper, represented by the SILO2 humanoid robot.

Eosinophilic fasciitis associated with hypereosinophilia, abnormal bone-marrow karyotype and inversion of chromosome 5.

Science.gov (United States)

Ferguson, J S; Bosworth, J; Min, T; Mercieca, J; Holden, C A

2014-03-01

We report the case of a male patient presenting with eosinophilia, pulmonary oedema and eosinophilic fasciitis (EF). He had the classic clinical appearance and magnetic resonance imaging of EF. Cytogenetic analysis of the bone marrow revealed a previously undescribed pericentric inversion of chromosome 5. Overall, the presentation was consistent with a diagnosis of chronic eosinophilic leukaemia, not otherwise specified (CEL-NOS). Dermatologists should consult a haematologist in cases of EF, in order to rule out possible haematological malignancies. © 2013 British Association of Dermatologists.

Gravimorphism in rice and barley: promotion of leaf elongation by vertical inversion in agravitropically growing plants.

Science.gov (United States)

Abe, K; Takahashi, H; Suge, H

1998-12-01

We have compared shoot responses of agravitropic rice and barley plants to vertical inversion with those of normal ones. When rice plants were vertically inverted, the main stems of a japonica type of rice, cv. Kamenoo, showed negative gravitropism at nodes 2-15 of both elongated and non-elongated internodes. However, shoots of lazy line of rice, lazy-Kamenoo, bent gravitropically at nodes 11-15 only elongated internodes but not at nodes 2-10 of non-elongated ones. Thus, shoots of Kamenoo responded gravitropically at all stages of growth, whereas shoots of lazy-Kamenoo did not show gravitropic response before heading. In Kamenoo plants, lengths of both leaf-sheath and leaf-blade were shortened by vertical inversion, but those of the vertically inverted plants of lazy-Kamenoo were significantly longer than the plants in an upright position. When agravitropic and normal plants of barley were vertically inverted, the same results as in rice were obtained; elongation of both leaf-sheath and leaf-blade was inhibited in normal barley plants, Chikurin-Ibaragi No. 1, but significantly stimulated in agravitropic plants of serpentina barley. These results suggest that vertical inversion of rice and barley plants enhances the elongation growth of leaves in the absence of tropistic response.

A new hybrid-FBP inversion algorithm with inverse distance backprojection weight for CT reconstruction

Energy Technology Data Exchange (ETDEWEB)

Narasimhadhan, A.V.; Rajgopal, Kasi

2011-07-01

This paper presents a new hybrid filtered backprojection (FBP) algorithm for fan-beam and cone-beam scan. The hybrid reconstruction kernel is the sum of the ramp and Hilbert filters. We modify the redundancy weighting function to reduce the inverse square distance weighting in the backprojection to inverse distance weight. The modified weight also eliminates the derivative associated with the Hilbert filter kernel. Thus, the proposed reconstruction algorithm has the advantages of the inverse distance weight in the backprojection. We evaluate the performance of the new algorithm in terms of the magnitude level and uniformity in noise for the fan-beam geometry. The computer simulations show that the spatial resolution is nearly identical to the standard fan-beam ramp filtered algorithm while the noise is spatially uniform and the noise variance is reduced. (orig.)

Association between cancer and contact allergy: a linkage study

DEFF Research Database (Denmark)

Engkilde, Kaare; Thyssen, Jacob P; Menné, Torkil

2011-01-01

by logistic regression analysis. Results An inverse association between contact allergy and non-melanoma skin- and breast cancer, respectively, was identified in both sexes, and an inverse trend for brain cancer was found in women with contact allergy. Additionally, a positive association between contact...... and cancer, few have looked into the association between cancer and contact allergy, a type IV allergy. By linking two clinical databases, the authors investigate the possible association between contact allergy and cancer. Methods Record linkage of two different registers was performed: (1) a tertiary...

Pericentric inversion of chromosome 11 (p14.3q21) associated with developmental delays, hypopigmented skin lesions and abnormal brain MRI findings - a new case report

Energy Technology Data Exchange (ETDEWEB)

Zachor, D.A.; Lofton, M. [Univ. of Alabama, Birmingham (United States)

1994-09-01

We report 3 year old male, referred for evaluation of developmental delays. Pregnancy was complicated by oligohydramnios, proteinuria and prematurity. Medical history revealed: bilateral inguinal hernia, small scrotal sac, undescended testes, developmental delays and behavioral problems. The child had: microcephaly, facial dysmorphic features, single palmar creases, hypopigmented skin lesions of variable size, intermittent exotropia and small retracted testes. Neurological examination was normal. Cognitive level was at the average range with mild delay in his adaptive behavior. Expressive language delays and severe articulation disorder were noted, as well as clumsiness, poor control and precision of gross and fine motor skills. Chromosomal analysis of peripheral leukocytes indicated that one of the number 11 chromosomes had undergone a pericentric inversion with breakpoints on the short (p) arm at band p14.3 and the long (q) arm at band q21. An MRI of the brain showed mild delay in myelinization pattern of white matter. Chromosome 11 inversion in other sites was associated with Beckwith-Wiedemann syndrome and several malignancies. To our knowledge this is the first description of inv(11)(p14.3q21) that is associated with microcephaly, dysmorphic features, hypopigmented skin lesions and speech delay. This inversion may disrupt the expression of the involved genes. However, additional cases with the same cytogenetic anomaly are needed to explore the phenotypic significance of this disorder.

Inverse transition radiation

International Nuclear Information System (INIS)

Steinhauer, L.C.; Romea, R.D.; Kimura, W.D.

1997-01-01

A new method for laser acceleration is proposed based upon the inverse process of transition radiation. The laser beam intersects an electron-beam traveling between two thin foils. The principle of this acceleration method is explored in terms of its classical and quantum bases and its inverse process. A closely related concept based on the inverse of diffraction radiation is also presented: this concept has the significant advantage that apertures are used to allow free passage of the electron beam. These concepts can produce net acceleration because they do not satisfy the conditions in which the Lawson-Woodward theorem applies (no net acceleration in an unbounded vacuum). Finally, practical aspects such as damage limits at optics are employed to find an optimized set of parameters. For reasonable assumptions an acceleration gradient of 200 MeV/m requiring a laser power of less than 1 GW is projected. An interesting approach to multi-staging the acceleration sections is also presented. copyright 1997 American Institute of Physics

EMERGENCE OF GRANULAR-SIZED MAGNETIC BUBBLES THROUGH THE SOLAR ATMOSPHERE. II. NON-LTE CHROMOSPHERIC DIAGNOSTICS AND INVERSIONS

Energy Technology Data Exchange (ETDEWEB)

Rodríguez, Jaime de la Cruz [Institute for Solar Physics, Department of Astronomy, Stockholm University, Albanova University Center, SE-10691 Stockholm (Sweden); Hansteen, Viggo; Ortiz, Ada [Institute of Theoretical Astrophysics, University of Oslo, P.O. Box 1029 Blindern, NO-0315 Oslo (Norway); Bellot-Rubio, Luis, E-mail: jaime@astro.su.se [Instituto de Astrofísica de Andalucía (CSIC), Apartado de Correos 3004, E-18080 Granada (Spain)

2015-09-10

Magnetic flux emergence into the outer layers of the Sun is a fundamental mechanism for releasing energy into the chromosphere and the corona. In this paper, we study the emergence of granular-sized flux concentrations and the structuring of the corresponding physical parameters and atmospheric diagnostics in the upper photosphere and in the chromosphere. We make use of a realistic 3D MHD simulation of the outer layers of the Sun to study the formation of the Ca ii 8542 line. We also derive semi-empirical 3D models from non-LTE inversions of our observations. These models contain information on the line-of-sight stratifications of temperature, velocity, and the magnetic field. Our analysis explains the peculiar Ca ii 8542 Å profiles observed in the flux emerging region. Additionally, we derive detailed temperature and velocity maps describing the ascent of a magnetic bubble from the photosphere to the chromosphere. The inversions suggest that, in active regions, granular-sized bubbles emerge up to the lower chromosphere where the existing large-scale field hinders their ascent. We report hints of heating when the field reaches the chromosphere.

An Inversion Disrupting FAM134B Is Associated with Sensory Neuropathy in the Border Collie Dog Breed.

Science.gov (United States)

Forman, Oliver P; Hitti, Rebekkah J; Pettitt, Louise; Jenkins, Christopher A; O'Brien, Dennis P; Shelton, G Diane; De Risio, Luisa; Quintana, Rodrigo Gutierrez; Beltran, Elsa; Mellersh, Cathryn

2016-09-08

Sensory neuropathy in the Border Collie is a severe neurological disorder caused by the degeneration of sensory and, to a lesser extent, motor nerve cells with clinical signs starting between 2 and 7 months of age. Using a genome-wide association study approach with three cases and 170 breed matched controls, a suggestive locus for sensory neuropathy was identified that was followed up using a genome sequencing approach. An inversion disrupting the candidate gene FAM134B was identified. Genotyping of additional cases and controls and RNAseq analysis provided strong evidence that the inversion is causal. Evidence of cryptic splicing resulting in novel exon transcription for FAM134B was identified by RNAseq experiments. This investigation demonstrates the identification of a novel sensory neuropathy associated mutation, by mapping using a minimal set of cases and subsequent genome sequencing. Through mutation screening, it should be possible to reduce the frequency of or completely eliminate this debilitating condition from the Border Collie breed population. Copyright © 2016 Forman et al.

Research Note: Full-waveform inversion of the unwrapped phase of a model

KAUST Repository

Alkhalifah, Tariq Ali

2013-12-06

Reflections in seismic data induce serious non-linearity in the objective function of full- waveform inversion. Thus, without a good initial velocity model that can produce reflections within a half cycle of the frequency used in the inversion, convergence to a solution becomes difficult. As a result, we tend to invert for refracted events and damp reflections in data. Reflection induced non-linearity stems from cycle skipping between the imprint of the true model in observed data and the predicted model in synthesized data. Inverting for the phase of the model allows us to address this problem by avoiding the source of non-linearity, the phase wrapping phenomena. Most of the information related to the location (or depths) of interfaces is embedded in the phase component of a model, mainly influenced by the background model, while the velocity-contrast information (responsible for the reflection energy) is mainly embedded in the amplitude component. In combination with unwrapping the phase of data, which mitigates the non-linearity introduced by the source function, I develop a framework to invert for the unwrapped phase of a model, represented by the instantaneous depth, using the unwrapped phase of the data. The resulting gradient function provides a mechanism to non-linearly update the velocity model by applying mainly phase shifts to the model. In using the instantaneous depth as a model parameter, we keep track of the model properties unfazed by the wrapping phenomena. © 2013 European Association of Geoscientists & Engineers.

Bilirubin concentration is positively associated with haemoglobin concentration and inversely associated with albumin to creatinine ratio among Indigenous Australians: eGFR Study.

Science.gov (United States)

Hughes, J T; Barzi, F; Hoy, W E; Jones, G R D; Rathnayake, G; Majoni, S W; Thomas, M A B; Sinha, A; Cass, A; MacIsaac, R J; O'Dea, K; Maple-Brown, L J

2017-12-01

Low serum bilirubin concentrations are reported to be strongly associated with cardio-metabolic disease, but this relationship has not been reported among Indigenous Australian people who are known to be at high risk for diabetes and chronic kidney disease (CKD). serum bilirubin will be negatively associated with markers of chronic disease, including CKD and anaemia among Indigenous Australians. A cross-sectional analysis of 594 adult Aboriginal and Torres Strait Islander (TSI) people in good health or with diabetes and markers of CKD. Measures included urine albumin: creatinine ratio (ACR), estimated glomerular filtration rate (eGFR), haemoglobin (Hb) and glycated haemoglobin (HbA1c). Diabetes was defined by medical history, medications or HbA1c≥6.5% or ≥48mmol/mol. Anaemia was defined as Hbbilirubin was performed. Participants mean (SD) age was 45.1 (14.5) years, and included 62.5% females, 71.7% Aboriginal, 41.1% with diabetes, 16.7% with anaemia, 41% with ACR>3mg/mmol and 18.2% with eGFRbilirubin concentration was lower in females than males (6 v 8μmol/L, pbilirubin; Hb and cholesterol (both positively related) and ACR, triglycerides, Aboriginal ethnicity and female gender (all inversely related). Serum bilirubin concentrations were positively associated with Hb and total cholesterol, and inversely associated with ACR. Further research to determine reasons explaining lower bilirubin concentrations among Aboriginal compared with TSI participants are needed. Copyright © 2017 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

The natural combination of full and image-based waveform inversion

KAUST Repository

Alkhalifah, Tariq Ali

2015-06-01

Integrating migration velocity analysis and full waveform inversion can help reduce the high non-linearity of the classic full waveform inversion objective function. The combination of inverting for the long and short wavelength components of the velocity model using a dual objective function that is sensitive to both components is still very expensive and have produced mixed results. We develop an approach that includes both components integrated to complement each other. We specifically utilize the image to generate reflections in our synthetic data only when the velocity model is not capable of producing such reflections. As a result, we get the migration velocity analysis working when we need it, and we mitigate its influence when the velocity model produces accurate reflections (possibly first for the low frequencies). This is achieved using a novel objective function that includes both objectives. Applications to a layered model and the Marmousi model demonstrate the main features of the approach. © 2015 European Association of Geoscientists & Engineers.

Waveform inversion of very long period impulsive signals associated with magmatic injection beneath Kilauea Volcano, Hawaii

Science.gov (United States)

Ohminato, T.; Chouet, B.A.; Dawson, P.; Kedar, S.

1998-01-01

We use data from broadband seismometers deployed around the summit of Kilauea Volcano to quantify the mechanism associated with a transient in the flow of magma feeding the east rift eruption of the volcano. The transient is marked by rapid inflation of the Kilauea summit peaking at 22 ??rad 4.5 hours after the event onset, followed by slow deflation over a period of 3 days. Superimposed on the summit inflation is a series of sawtooth displacement pulses, each characterized by a sudden drop in amplitude lasting 5-10 s followed by an exponential recovery lasting 1-3 min. The sawtooth waveforms display almost identical shapes, suggesting a process involving the repeated activation of a fixed source. The particle motion associated with each sawtooth is almost linear, and its major swing shows compressional motion at all stations. Analyses of semblance and particle motion are consistent with a point source located 1 km beneath the northeast edge of the Halemaumau pit crater. To estimate the source mechanism, we apply a moment tensor inversion to the waveform data, assuming a point source embedded in a homogeneous half-space with compressional and shear wave velocities representative of the average medium properties at shallow depth under Kilauea. Synthetic waveforms are constructed by a superposition of impulse responses for six moment tensor components and three single force components. The origin times of individual impulses are distributed along the time axis at appropriately small, equal intervals, and their amplitudes are determined by least squares. In this inversion, the source time functions of the six tensor and three force components are determined simultaneously. We confirm the accuracy of the inversion method through a series of numerical tests. The results from the inversion show that the waveform data are well explained by a pulsating transport mechanism operating on a subhorizontal crack linking the summit reservoir to the east rift of Kilauea. The crack

[Inverse probability weighting (IPW) for evaluating and "correcting" selection bias].

Science.gov (United States)

Narduzzi, Silvia; Golini, Martina Nicole; Porta, Daniela; Stafoggia, Massimo; Forastiere, Francesco

2014-01-01

the Inverse probability weighting (IPW) is a methodology developed to account for missingness and selection bias caused by non-randomselection of observations, or non-random lack of some information in a subgroup of the population. to provide an overview of IPW methodology and an application in a cohort study of the association between exposure to traffic air pollution (nitrogen dioxide, NO₂) and 7-year children IQ. this methodology allows to correct the analysis by weighting the observations with the probability of being selected. The IPW is based on the assumption that individual information that can predict the probability of inclusion (non-missingness) are available for the entire study population, so that, after taking account of them, we can make inferences about the entire target population starting from the nonmissing observations alone.The procedure for the calculation is the following: firstly, we consider the entire population at study and calculate the probability of non-missing information using a logistic regression model, where the response is the nonmissingness and the covariates are its possible predictors.The weight of each subject is given by the inverse of the predicted probability. Then the analysis is performed only on the non-missing observations using a weighted model. IPW is a technique that allows to embed the selection process in the analysis of the estimates, but its effectiveness in "correcting" the selection bias depends on the availability of enough information, for the entire population, to predict the non-missingness probability. In the example proposed, the IPW application showed that the effect of exposure to NO2 on the area of verbal intelligence quotient of children is stronger than the effect showed from the analysis performed without regard to the selection processes.

Calculation of the inverse data space via sparse inversion

KAUST Repository

Saragiotis, Christos

2011-01-01

The inverse data space provides a natural separation of primaries and surface-related multiples, as the surface multiples map onto the area around the origin while the primaries map elsewhere. However, the calculation of the inverse data is far from trivial as theory requires infinite time and offset recording. Furthermore regularization issues arise during inversion. We perform the inversion by minimizing the least-squares norm of the misfit function by constraining the $ell_1$ norm of the solution, being the inverse data space. In this way a sparse inversion approach is obtained. We show results on field data with an application to surface multiple removal.

Physical activity is inversely associated with multimorbidity in elderly men: results from the KORA-Age Augsburg Study.

Science.gov (United States)

Autenrieth, Christine S; Kirchberger, Inge; Heier, Margit; Zimmermann, Anja-Kerstin; Peters, Annette; Döring, Angela; Thorand, Barbara

2013-07-01

Physical activity is suggested to play a key role in the prevention of several chronic diseases. However, data on the association between physical activity and multimorbidity are lacking. Using data from 1007 men and women aged 65-94 years who participated in the population-based KORA (Cooperative Health Research in the Region of Augsburg)-Age project conducted in Augsburg/Germany and two adjacent counties in 2008/09, 13 chronic conditions were identified, and physical activity scores were calculated based on the self-reported physical activity scale for the elderly (PASE). Multivariable sex-specific logistic regression was applied to determine the association of the continuous physical activity score with multimorbidity (≥ 2 out of 13 diseases). Physical activity (mean PASE score±SD) was higher in men (125.1 ± 59.2) than in women (112.2 ± 49.2). Among men, the odds ratio (OR) for multimorbidity was 0.73 (95% CI: 0.60-0.90) for a 1 standard deviation increase of the PASE score. No significant results could be observed for women (OR: 1.05; 95% CI: 0.83-1.33). We demonstrated an inverse association between physical activity and multimorbidity among men. Further prospective studies have to confirm the temporality of effects. Copyright © 2013 Elsevier Inc. All rights reserved.

Inverse photoemission of uranium oxides

International Nuclear Information System (INIS)

Roussel, P.; Morrall, P.; Tull, S.J.

2009-01-01

Understanding the itinerant-localised bonding role of the 5f electrons in the light actinides will afford an insight into their unusual physical and chemical properties. In recent years, the combination of core and valance band electron spectroscopies with theoretic modelling have already made significant progress in this area. However, information of the unoccupied density of states is still scarce. When compared to the forward photoemission techniques, measurements of the unoccupied states suffer from significantly less sensitivity and lower resolution. In this paper, we report on our experimental apparatus, which is designed to measure the inverse photoemission spectra of the light actinides. Inverse photoemission spectra of UO 2 and UO 2.2 along with the corresponding core and valance electron spectra are presented in this paper. UO 2 has been reported previously, although through its inclusion here it allows us to compare and contrast results from our experimental apparatus to the previous Bremsstrahlung Isochromat Spectroscopy and Inverse Photoemission Spectroscopy investigations

Endometriosis Might Be Inversely Associated with Developing Chronic Kidney Disease: A Population-Based Cohort Study in Taiwan

Directory of Open Access Journals (Sweden)

Ben-Shian Huang

2016-07-01

Full Text Available This study was conducted to determine the risk of chronic kidney disease (CKD among women with endometriosis in Taiwan. We conducted a retrospective cohort study using the National Health Insurance Research Database of Taiwan. A total of 27,973 women with a diagnosis of endometriosis and 27,973 multivariable-matched controls (1:1 from 2000 to 2010 were selected. Cox regression and computed hazard ratios (HR with 95% confidence intervals (95% CI were used to determine the risk of CKD among women with endometriosis. The incidence rates (IR, per 10,000 person-years of CKD among women with and without endometriosis were 4.64 and 7.01, respectively, with a significantly decreased risk of CKD (crude HR 0.65, 95% CI 0.53–0.81; adjusted HR 0.69, 95% CI 0.56–0.86 among women with endometriosis. The IR of CKD progressively increased with age, but the trend of lower CKD risk among women with endometriosis was consistent. However, the lower risk of CKD in women with endometriosis was no longer statistically significant after adjusting for menopausal status (adjusted HR 0.85, 95% CI 0.65–1.10. The results suggest that endometriosis is inversely associated with CKD, but this effect was mediated by menopause. The possible mechanism of this association is worthy of further evaluation.

Patient-reported non-adherence and immunosuppressant trough levels are associated with rejection after renal transplantation.

Science.gov (United States)

Scheel, Jennifer; Reber, Sandra; Stoessel, Lisa; Waldmann, Elisabeth; Jank, Sabine; Eckardt, Kai-Uwe; Grundmann, Franziska; Vitinius, Frank; de Zwaan, Martina; Bertram, Anna; Erim, Yesim

2017-03-29

Different measures of non-adherence to immunosuppressant (IS) medication have been found to be associated with rejection episodes after successful transplantation. The aim of the current study was to investigate whether graft rejection after renal transplantation is associated with patient-reported IS medication non-adherence and IS trough level variables (IS trough level variability and percentage of sub-therapeutic IS trough levels). Patient-reported non-adherence, IS trough level variability, percentage of sub-therapeutic IS trough levels, and acute biopsy-proven late allograft rejections were assessed in 267 adult renal transplant recipients who were ≥12 months post-transplantation. The rate of rejection was 13.5%. IS trough level variability, percentage of sub-therapeutic IS trough levels as well as patient-reported non-adherence were all significantly and positively associated with rejection, but not with each other. Logistic regression analyses revealed that only the percentage of sub-therapeutic IS trough levels and age at transplantation remained significantly associated with rejection. Particularly, the percentage of sub-therapeutic IS trough levels is associated with acute rejections after kidney transplantation whereas IS trough level variability and patient-reported non-adherence seem to be of subordinate importance. Patient-reported non-adherence and IS trough level variables were not correlated; thus, non-adherence should always be measured in a multi-methodological approach. Further research concerning the best combination of non-adherence measures is needed.

Non-driver mutations in myeloproliferative neoplasm-associated myelofibrosis

Directory of Open Access Journals (Sweden)

Bing Li

2017-05-01

Full Text Available Abstract We studied non-driver mutations in 62 subjects with myeloproliferative neoplasm (MPN-associated myelofibrosis upon diagnosis, including 45 subjects with primary myelofibrosis (PMF and 17 with post-polycythemia vera or post-essential thrombocythemia myelofibrosis (post-PV/ET MF. Fifty-eight subjects had ≥1 non-driver mutation upon diagnosis. Mutations in mRNA splicing genes, especially in U2AF1, were significantly more frequent in PMF than in post-PV/ET MF (33 vs. 6%; P = 0.015. There were also striking differences in clonal architecture. These data indicate different genomic spectrums between PMF and post-PV/ET MF.

High resolution tsunami inversion for 2010 Chile earthquake

Directory of Open Access Journals (Sweden)

T.-R. Wu

2011-12-01

Full Text Available We investigate the feasibility of inverting high-resolution vertical seafloor displacement from tsunami waveforms. An inversion method named "SUTIM" (small unit tsunami inversion method is developed to meet this goal. In addition to utilizing the conventional least-square inversion, this paper also enhances the inversion resolution by Grid-Shifting method. A smooth constraint is adopted to gain stability. After a series of validation and performance tests, SUTIM is used to study the 2010 Chile earthquake. Based upon data quality and azimuthal distribution, we select tsunami waveforms from 6 GLOSS stations and 1 DART buoy record. In total, 157 sub-faults are utilized for the high-resolution inversion. The resolution reaches 10 sub-faults per wavelength. The result is compared with the distribution of the aftershocks and waveforms at each gauge location with very good agreement. The inversion result shows that the source profile features a non-uniform distribution of the seafloor displacement. The highly elevated vertical seafloor is mainly concentrated in two areas: one is located in the northern part of the epicentre, between 34° S and 36° S; the other is in the southern part, between 37° S and 38° S.

High resolution tsunami inversion for 2010 Chile earthquake

Science.gov (United States)

Wu, T.-R.; Ho, T.-C.

2011-12-01

We investigate the feasibility of inverting high-resolution vertical seafloor displacement from tsunami waveforms. An inversion method named "SUTIM" (small unit tsunami inversion method) is developed to meet this goal. In addition to utilizing the conventional least-square inversion, this paper also enhances the inversion resolution by Grid-Shifting method. A smooth constraint is adopted to gain stability. After a series of validation and performance tests, SUTIM is used to study the 2010 Chile earthquake. Based upon data quality and azimuthal distribution, we select tsunami waveforms from 6 GLOSS stations and 1 DART buoy record. In total, 157 sub-faults are utilized for the high-resolution inversion. The resolution reaches 10 sub-faults per wavelength. The result is compared with the distribution of the aftershocks and waveforms at each gauge location with very good agreement. The inversion result shows that the source profile features a non-uniform distribution of the seafloor displacement. The highly elevated vertical seafloor is mainly concentrated in two areas: one is located in the northern part of the epicentre, between 34° S and 36° S; the other is in the southern part, between 37° S and 38° S.

Anisotropic magnetotelluric inversion using a mutual information constraint

Science.gov (United States)

Mandolesi, E.; Jones, A. G.

2012-12-01

In recent years, several authors pointed that the electrical conductivity of many subsurface structures cannot be described properly by a scalar field. With the development of field devices and techniques, data quality improved to the point that the anisotropy in conductivity of rocks (microscopic anisotropy) and tectonic structures (macroscopic anisotropy) cannot be neglected. Therefore a correct use of high quality data has to include electrical anisotropy and a correct interpretation of anisotropic data characterizes directly a non-negligible part of the subsurface. In this work we test an inversion routine that takes advantage of the classic Levenberg-Marquardt (LM) algorithm to invert magnetotelluric (MT) data generated from a bi-dimensional (2D) anisotropic domain. The LM method is routinely used in inverse problems due its performance and robustness. In non-linear inverse problems -such the MT problem- the LM method provides a spectacular compromise betwee quick and secure convergence at the price of the explicit computation and storage of the sensitivity matrix. Regularization in inverse MT problems has been used extensively, due to the necessity to constrain model space and to reduce the ill-posedness of the anisotropic MT problem, which makes MT inversions extremely challenging. In order to reduce non-uniqueness of the MT problem and to reach a model compatible with other different tomographic results from the same target region, we used a mutual information (MI) based constraint. MI is a basic quantity in information theory that can be used to define a metric between images, and it is routinely used in fields as computer vision, image registration and medical tomography, to cite some applications. We -thus- inverted for the model that best fits the anisotropic data and that is the closest -in a MI sense- to a tomographic model of the target area. The advantage of this technique is that the tomographic model of the studied region may be produced by any

Non-contrast-enhanced hepatic MR angiography: Do two-dimensional parallel imaging and short tau inversion recovery methods shorten acquisition time without image quality deterioration?

Energy Technology Data Exchange (ETDEWEB)

Shimada, Kotaro, E-mail: kotaro@kuhp.kyoto-u.ac.jp [Department of Diagnostic Imaging and Nuclear Medicine, Kyoto University, Graduate School of Medicine, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507 (Japan); Isoda, Hiroyoshi, E-mail: sayuki@kuhp.kyoto-u.ac.jp [Department of Diagnostic Imaging and Nuclear Medicine, Kyoto University, Graduate School of Medicine, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507 (Japan); Okada, Tomohisa, E-mail: tomokada@kuhp.kyoto-u.ac.jp [Department of Diagnostic Imaging and Nuclear Medicine, Kyoto University, Graduate School of Medicine, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507 (Japan); Kamae, Toshikazu, E-mail: toshi13@kuhp.kyoto-u.ac.jp [Department of Diagnostic Imaging and Nuclear Medicine, Kyoto University, Graduate School of Medicine, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507 (Japan); Arizono, Shigeki, E-mail: arizono@kuhp.kyoto-u.ac.jp [Department of Diagnostic Imaging and Nuclear Medicine, Kyoto University, Graduate School of Medicine, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507 (Japan); Hirokawa, Yuusuke, E-mail: yuusuke@kuhp.kyoto-u.ac.jp [Department of Diagnostic Imaging and Nuclear Medicine, Kyoto University, Graduate School of Medicine, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507 (Japan); Shibata, Toshiya, E-mail: ksj@kuhp.kyoto-u.ac.jp [Department of Diagnostic Imaging and Nuclear Medicine, Kyoto University, Graduate School of Medicine, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507 (Japan); Togashi, Kaori, E-mail: ktogashi@kuhp.kyoto-u.ac.jp [Department of Diagnostic Imaging and Nuclear Medicine, Kyoto University, Graduate School of Medicine, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507 (Japan)

2011-01-15

Objective: To study whether shortening the acquisition time for selective hepatic artery visualization is feasible without image quality deterioration by adopting two-dimensional (2D) parallel imaging (PI) and short tau inversion recovery (STIR) methods. Materials and methods: Twenty-four healthy volunteers were enrolled. 3D true steady-state free-precession imaging with a time spatial labeling inversion pulse was conducted using 1D or 2D-PI and fat suppression by chemical shift selective (CHESS) or STIR methods. Three groups of different scan conditions were assigned and compared: group A (1D-PI factor 2 and CHESS), group B (2D-PI factor 2 x 2 and CHESS), and group C (2D-PI factor 2 x 2 and STIR). The artery-to-liver contrast was quantified, and the quality of artery visualization and overall image quality were scored. Results: The mean scan time was 9.5 {+-} 1.0 min (mean {+-} standard deviation), 5.9 {+-} 0.8 min, and 5.8 {+-} 0.5 min in groups A, B, and C, respectively, and was significantly shorter in groups B and C than in group A (P < 0.01). The artery-to-liver contrast was significantly better in group C than in groups A and B (P < 0.01). The scores for artery visualization and overall image quality were worse in group B than in groups A and C. The differences were statistically significant (P < 0.05) regarding the arterial branches of segments 4 and 8. Between group A and group C, which had similar scores, there were no statistically significant differences. Conclusion: Shortening the acquisition time for selective hepatic artery visualization was feasible without deterioration of the image quality by the combination of 2D-PI and STIR methods. It will facilitate using non-contrast-enhanced MRA in clinical practice.

Non-contrast-enhanced hepatic MR angiography: Do two-dimensional parallel imaging and short tau inversion recovery methods shorten acquisition time without image quality deterioration?

International Nuclear Information System (INIS)

Shimada, Kotaro; Isoda, Hiroyoshi; Okada, Tomohisa; Kamae, Toshikazu; Arizono, Shigeki; Hirokawa, Yuusuke; Shibata, Toshiya; Togashi, Kaori

2011-01-01

Objective: To study whether shortening the acquisition time for selective hepatic artery visualization is feasible without image quality deterioration by adopting two-dimensional (2D) parallel imaging (PI) and short tau inversion recovery (STIR) methods. Materials and methods: Twenty-four healthy volunteers were enrolled. 3D true steady-state free-precession imaging with a time spatial labeling inversion pulse was conducted using 1D or 2D-PI and fat suppression by chemical shift selective (CHESS) or STIR methods. Three groups of different scan conditions were assigned and compared: group A (1D-PI factor 2 and CHESS), group B (2D-PI factor 2 x 2 and CHESS), and group C (2D-PI factor 2 x 2 and STIR). The artery-to-liver contrast was quantified, and the quality of artery visualization and overall image quality were scored. Results: The mean scan time was 9.5 ± 1.0 min (mean ± standard deviation), 5.9 ± 0.8 min, and 5.8 ± 0.5 min in groups A, B, and C, respectively, and was significantly shorter in groups B and C than in group A (P < 0.01). The artery-to-liver contrast was significantly better in group C than in groups A and B (P < 0.01). The scores for artery visualization and overall image quality were worse in group B than in groups A and C. The differences were statistically significant (P < 0.05) regarding the arterial branches of segments 4 and 8. Between group A and group C, which had similar scores, there were no statistically significant differences. Conclusion: Shortening the acquisition time for selective hepatic artery visualization was feasible without deterioration of the image quality by the combination of 2D-PI and STIR methods. It will facilitate using non-contrast-enhanced MRA in clinical practice.

Identification of sequence motifs significantly associated with antisense activity

Directory of Open Access Journals (Sweden)

Peek Andrew S

2007-06-01

Full Text Available Abstract Background Predicting the suppression activity of antisense oligonucleotide sequences is the main goal of the rational design of nucleic acids. To create an effective predictive model, it is important to know what properties of an oligonucleotide sequence associate significantly with antisense activity. Also, for the model to be efficient we must know what properties do not associate significantly and can be omitted from the model. This paper will discuss the results of a randomization procedure to find motifs that associate significantly with either high or low antisense suppression activity, analysis of their properties, as well as the results of support vector machine modelling using these significant motifs as features. Results We discovered 155 motifs that associate significantly with high antisense suppression activity and 202 motifs that associate significantly with low suppression activity. The motifs range in length from 2 to 5 bases, contain several motifs that have been previously discovered as associating highly with antisense activity, and have thermodynamic properties consistent with previous work associating thermodynamic properties of sequences with their antisense activity. Statistical analysis revealed no correlation between a motif's position within an antisense sequence and that sequences antisense activity. Also, many significant motifs existed as subwords of other significant motifs. Support vector regression experiments indicated that the feature set of significant motifs increased correlation compared to all possible motifs as well as several subsets of the significant motifs. Conclusion The thermodynamic properties of the significantly associated motifs support existing data correlating the thermodynamic properties of the antisense oligonucleotide with antisense efficiency, reinforcing our hypothesis that antisense suppression is strongly associated with probe/target thermodynamics, as there are no enzymatic

Consumption of minimally processed food is inversely associated with excess weight in adolescents living in an underdeveloped city.

Science.gov (United States)

Melo, Ingrid Sofia Vieira de; Costa, Clara Andrezza Crisóstomo Bezerra; Santos, João Victor Laurindo Dos; Santos, Aldenir Feitosa Dos; Florêncio, Telma Maria de Menezes Toledo; Bueno, Nassib Bezerra

2017-01-01

The consumption of ultra-processed foods may be associated with the development of chronic diseases, both in adults and in children/adolescents. This consumption is growing worldwide, especially in low and middle-income countries. Nevertheless, its magnitude in small, poor cities from the countryside is not well characterized, especially in adolescents. This study aimed to assess the consumption of minimally processed, processed and ultra-processed foods by adolescents from a poor Brazilian city and to determine if it was associated with excess weight, high waist circumference and high blood pressure. Cross-sectional study, conducted at a public federal school that offers technical education together with high school, located in the city of Murici. Adolescents of both sexes and aged between 14-19 years old were included. Anthropometric characteristics (weight, height, waist circumference), blood pressure, and dietary intake data were assessed. Associations were calculated using Poisson regression models, adjusted by sex and age. At total, 249 adolescents were included, being 55.8% girls, with a mean age of 16 years-old. The consumption of minimally processed foods was inversely associated with excess weight (Adjusted Prevalence Ratio: 0.61, 95% Confidence Interval: [0.39-0.96], P = 0.03). Although the consumption of ultra-processed foods was not associated with excess weight, high blood pressure and high waist circumference, 46.2% of the sample reported eating these products more than weekly. Consumption of minimally processed food is inversely associated with excess weight in adolescents. Investments in nutritional education aiming the prevention of chronic diseases associated with the consumption of these foods are necessary.

The Idea Is Good, but…: Failure to Replicate Associations of Oxytocinergic Polymorphisms with Face-Inversion in the N170.

Directory of Open Access Journals (Sweden)

Aisha J L Munk

Full Text Available In event-related potentials, the N170 manifests itself especially in reaction to faces. In the healthy population, face-inversion leads to stronger negative amplitudes and prolonged latencies of the N170, effects not being present in patients with autism-spectrum-disorder (ASD. ASD has frequently been associated with differences in oxytocinergic neurotransmission. This ERP-study aimed to investigate the face-inversion effect in association with oxytocinergic candidate genes. It was expected that risk-allele-carriers of the oxytocin-receptor-gene-polymorphism (rs53576 and of CD38 (rs379863 responded similar to upright and inverted faces as persons with ASD. Additionally, reactions to different facial emotional expressions were studied. As there have been difficulties with replications of those molecular genetic association studies, we aimed to replicate our findings in a second study.Seventy-two male subjects in the first-, and seventy-eight young male subjects in the replication-study conducted a face-inversion-paradigm, while recording EEG. DNA was extracted from buccal cells.Results revealed stronger N170-amplitudes and longer latencies in reaction to inverted faces in comparison to upright ones. Furthermore, effects of emotion on N170 were evident. Those effects were present in the first and in the second study. Whereas we found molecular-genetic associations of oxytocinergic polymorphisms with the N170 in the first study, we failed to do so in the replication sample.Results indicate that a deeper theoretical understanding of this research-field is needed, in order to generate possible explanations for these findings. Results, furthermore, support the hypotheses that success of reproducibility is correlated with strength of lower original p-values and larger effect sizes in the original study.

Significance of genetic variants in DLC1 and their association with hepatocellular carcinoma

Science.gov (United States)

XIE, CHENG-RONG; SUN, HONG-GUANG; SUN, YU; ZHAO, WEN-XIU; ZHANG, SHENG; WANG, XIAO-MIN; YIN, ZHEN-YU

2015-01-01

DLC1 has been shown to be downregulated or absent in hepatocellular carcinoma (HCC) and is associated with tumorigenesis and development. However, only a small number of studies have focused on genetic variations of DLC1. The present study performed exon sequencing for the DLC1 gene in HCC tissue samples from 105 patients to identify functional genetic variation of DLC1 and its association with HCC susceptibility, clinicopathological features and prognosis. A novel missense mutation and four non-synonymous single nucleotide polymorphisms (SNPs; rs3816748, rs11203495, rs3816747 and rs532841) were identified. A significant correlation of rs3816747 polymorphisms with HCC susceptibility was identified. Compared to individuals with the GG genotype of rs3816747, those with the GA (odds ratio (OR)=0.486; P=0.037) or GA+AA genotype (OR=0.51; P=0.039) were associated with a significantly decreased HCC risk. Furthermore, patients with the GC+CC genotype of rs3816748, the TC+CC genotype of rs11203495 or the GA+AA genotype of rs3816747 had small-sized tumors compared with those carrying the wild-type genotype. No significant association of DLC1 SNPs with the patients' prognosis was found. These results indicated that genetic variations in the DLC1 gene may confer a risk for HCC. PMID:26095787

Whole Blood ω-3 Fatty Acids Are Inversely Associated with Carotid Intima-Media Thickness in Indigenous Mexican Women.

Science.gov (United States)

Monge, Adriana; Harris, William S; Ortiz-Panozo, Eduardo; Yunes, Elsa; Cantu-Brito, Carlos; Catzin-Kuhlmann, Andres; López-Ridaura, Ruy; Lajous, Martín

2016-07-01

Long-chain ω-3 (n-3) polyunsaturated fatty acids (PUFAs) may reduce the risk of atherosclerosis. The association between n-3 PUFAs and cardiovascular disease may vary across different populations, and there is limited information on Hispanic individuals with mixed Amerindian and European origin. We evaluated the cross-sectional relations between whole blood n-3 PUFAs and carotid intima-media thickness (IMT) in Mexican women living in Mexico and assessed whether this relation was different in women who spoke an indigenous language compared with women who did not. In 2012-2013, we assessed the association between blood n-3 PUFAs and IMT in 1306 women free of disease in Chiapas and Yucatan, Mexico. We categorized blood n-3 PUFAs (% of total FAs) in quartiles and adjusted linear regression models by age, indigenous language, site, socioeconomic status, education, smoking, menopause, diabetes, hypertension, hypercholesterolemia, body mass index, physical activity, and diet. We stratified analyses by indigenous/nonindigenous language speakers (n = 315 of 991). Whole blood n-3 PUFAs (means ± SDs) were 3.58% ± 0.78% of total FAs. We did not observe a significant association between n-3 PUFAs and IMT in the overall study population. However, the adjusted mean difference of IMT was -6.5% (95% CI: -10.7%, -2.3%; P-trend women in the highest quartile compared with the lowest quartile of blood n-3 PUFAs. In nonindigenous women, we did not observe an association (-0.6%; 95% CI: -3.0%, 1.8%, comparing extreme quartiles; P-trend = 1.00). Overall, circulating n-3 PUFAs were not associated with IMT. However, we observed a strong statistically significant inverse association with IMT in indigenous Mexican women. Future studies should evaluate genetic markers that may reflect differences in n-3 PUFA metabolism across populations. © 2016 American Society for Nutrition.

Intake of specific nonfermented soy foods may be inversely associated with risk of distal gastric cancer in a Chinese population.

Science.gov (United States)

Kweon, Sun-Seog; Shu, Xiao-Ou; Xiang, Yongbing; Cai, Hui; Yang, Gong; Ji, Bu-Tian; Li, Honglan; Gao, Yu-Tang; Zheng, Wei; Epplein, Meira

2013-11-01

Because the association between soy consumption and gastric cancer is inconsistent, we evaluated the putative preventive effect of soy food on gastric cancer risk in the Shanghai Women's and Men's Health Studies, comprising a total of 128,687 participants. Intake of nonfermented soy foods was estimated using 2 validated food-frequency questionnaires. HRs were calculated with 95% CIs for intake amounts of total nonfermented soy food intake, soy protein, and isoflavones as well as individual soy food groups using Cox proportional hazards regression. A total of 493 distal gastric cancer cases were identified by 2010. Although all risk estimates for summary measures of soy food intake above the lowest quartile (quartile 1) were suggestive of a protective effect, no statistically significant associations with risk of distal gastric cancer were found. Among the separate soy food groups, significant reductions in risk of distal gastric cancer by increasing intake of tofu were found in men in quartile 2 (HR: 0.59; 95% CI: 0.40, 0.86), quartile 3 (HR: 0.62; 95% CI: 0.44, 0.88), and quartile 4 (HR: 0.64; 95% CI: 0.42, 0.99), resulting in a significant trend (P-trend = 0.02). Dry bean intake was also inversely associated with decreased risk of gastric cancer, but in postmenopausal women only [quartile 2 (HR: 0.54; 95% CI: 0.30, 0.96); quartile 3 (HR: 0.90; 95% CI: 0.64, 1.27); and quartile 4 (HR: 0.63; 95% CI: 0.43, 0.91)], resulting in a significant trend (P-trend = 0.03). Overall, our study found no statistically significant association between nonfermented soy food intake and distal gastric cancer risk, though the data supported the hypothesis that tofu may protect against distal gastric cancer in men and dry bean consumption may decrease the risk of gastric cancer in postmenopausal women.

Psychosocial factors associated with non-smoking adolescents' intentions to smoke.

Science.gov (United States)

Smith, Brian N; Bean, Melanie K; Mitchell, Karen S; Speizer, Ilene S; Fries, Elizabeth A

2007-04-01

Smoking is the most preventable cause of death in the United States. Most adult smokers began smoking during adolescence, making youth tobacco prevention an especially important public health goal. Guided by an extension of the theory of planned behavior (TPB), this study examined the role of psychosocial factors in accounting for adolescents' smoking intentions. Participants from three high schools (n = 785) were surveyed to assess smoking-related characteristics and behaviors as part of a statewide evaluation of tobacco prevention programming. Attitudes, subjective norms (and other normative factors) and perceived behavioral control were all associated with non-smokers' intentions to smoke. Having more favorable attitudes toward remaining tobacco free and perceiving that friends would not be supportive of smoking were both associated with decreased likelihood of intending to smoke. Normative influence and peer use were significant factors, such that having more friends who smoke was associated with increased odds of intent to smoke. Lastly, perceived difficulty to quit was related to smoking intentions, with higher confidence to quit significantly associated with intentions to smoke. Findings are consistent with the TPB--attitudes, normative factors and perceived behavioral control each helped account for non-smoking adolescents' intentions to smoke. Implications for theory and intervention building are discussed.

The formaldehyde budget as seen by a global-scale multi-constraint and multi-species inversion system

Directory of Open Access Journals (Sweden)

A. Fortems-Cheiney

2012-08-01

Full Text Available For the first time, carbon monoxide (CO and formaldehyde (HCHO satellite retrievals are used together with methane (CH₄ and methyl choloroform (CH₃CCl₃ or MCF surface measurements in an advanced inversion system. The CO and HCHO are respectively from the MOPITT and OMI instruments. The multi-species and multi-satellite dataset inversion is done for the 2005–2010 period. The robustness of our results is evaluated by comparing our posterior-modeled concentrations with several sets of independent measurements of atmospheric mixing ratios. The inversion leads to significant changes from the prior to the posterior, in terms of magnitude and seasonality of the CO and CH₄ surface fluxes and of the HCHO production by non-methane volatile organic compounds (NMVOC. The latter is significantly decreased, indicating an overestimation of the biogenic NMVOC emissions, such as isoprene, in the GEIA inventory. CO and CH₄ surface emissions are increased by the inversion, from 1037 to 1394 TgCO and from 489 to 529 TgCH₄ on average for the 2005–2010 period. CH₄ emissions present significant interannual variability and a joint CO-CH₄ fluxes analysis reveals that tropical biomass burning probably played a role in the recent increase of atmospheric methane.

Quantifying uncertainties of seismic Bayesian inversion of Northern Great Plains

Science.gov (United States)

Gao, C.; Lekic, V.

2017-12-01

Elastic waves excited by earthquakes are the fundamental observations of the seismological studies. Seismologists measure information such as travel time, amplitude, and polarization to infer the properties of earthquake source, seismic wave propagation, and subsurface structure. Across numerous applications, seismic imaging has been able to take advantage of complimentary seismic observables to constrain profiles and lateral variations of Earth's elastic properties. Moreover, seismic imaging plays a unique role in multidisciplinary studies of geoscience by providing direct constraints on the unreachable interior of the Earth. Accurate quantification of uncertainties of inferences made from seismic observations is of paramount importance for interpreting seismic images and testing geological hypotheses. However, such quantification remains challenging and subjective due to the non-linearity and non-uniqueness of geophysical inverse problem. In this project, we apply a reverse jump Markov chain Monte Carlo (rjMcMC) algorithm for a transdimensional Bayesian inversion of continental lithosphere structure. Such inversion allows us to quantify the uncertainties of inversion results by inverting for an ensemble solution. It also yields an adaptive parameterization that enables simultaneous inversion of different elastic properties without imposing strong prior information on the relationship between them. We present retrieved profiles of shear velocity (Vs) and radial anisotropy in Northern Great Plains using measurements from USArray stations. We use both seismic surface wave dispersion and receiver function data due to their complementary constraints of lithosphere structure. Furthermore, we analyze the uncertainties of both individual and joint inversion of those two data types to quantify the benefit of doing joint inversion. As an application, we infer the variation of Moho depths and crustal layering across the northern Great Plains.

Off-shell T-matrices from inverse scattering

International Nuclear Information System (INIS)

Von Geramb, H.V.; Amos, K.A.

1989-01-01

Inverse scattering theory is used to determine local, energy independent, coordinate space nucleon-nucleon potentials. Inversions are made of phase shifts obtained by analyzes of data and from meson exchange theory, in particular the Paris and the Bonn parametrizations. Half off-shell T-matrices are generated to compare the exact meson theoretical results with those of inversion and it is found that phase equivalent interactions have essentially the same off-shell behaviour for any physically significant range of momenta. 8 refs., 8 figs

Riemann–Hilbert problem approach for two-dimensional flow inverse scattering

Energy Technology Data Exchange (ETDEWEB)

Agaltsov, A. D., E-mail: agalets@gmail.com [Faculty of Computational Mathematics and Cybernetics, Lomonosov Moscow State University, 119991 Moscow (Russian Federation); Novikov, R. G., E-mail: novikov@cmap.polytechnique.fr [CNRS (UMR 7641), Centre de Mathématiques Appliquées, Ecole Polytechnique, 91128 Palaiseau (France); IEPT RAS, 117997 Moscow (Russian Federation); Moscow Institute of Physics and Technology, Dolgoprudny (Russian Federation)

2014-10-15

We consider inverse scattering for the time-harmonic wave equation with first-order perturbation in two dimensions. This problem arises in particular in the acoustic tomography of moving fluid. We consider linearized and nonlinearized reconstruction algorithms for this problem of inverse scattering. Our nonlinearized reconstruction algorithm is based on the non-local Riemann–Hilbert problem approach. Comparisons with preceding results are given.

Riemann–Hilbert problem approach for two-dimensional flow inverse scattering

International Nuclear Information System (INIS)

Agaltsov, A. D.; Novikov, R. G.

2014-01-01

We consider inverse scattering for the time-harmonic wave equation with first-order perturbation in two dimensions. This problem arises in particular in the acoustic tomography of moving fluid. We consider linearized and nonlinearized reconstruction algorithms for this problem of inverse scattering. Our nonlinearized reconstruction algorithm is based on the non-local Riemann–Hilbert problem approach. Comparisons with preceding results are given

Polytene chromosome map and inversion polymorphism in Drosophila mediopunctata

Directory of Open Access Journals (Sweden)

Galina Ananina

2002-07-01

Full Text Available Drosophila mediopunctata belongs to the tripunctata group, and is one of the commonest Drosophila species collected in some places in Brazil, especially in the winter. A standard map of the polytene chromosomes is presented. The breakpoints of the naturally occurring chromosomal rearrangements are marked on the map. The distribution of breaking points through the chromosomes of D. mediopunctata is apparently non-random. Chromosomes X, II and IV show inversion polymorphisms. Chromosome II is the most polymorphic, with 17 inversions, 8 inversions in the distal region and 9 in the proximal region. Chromosome X has four different gene arrangements, while chromosome IV has only two.

Multi-objective optimization of inverse planning for accurate radiotherapy

International Nuclear Information System (INIS)

Cao Ruifen; Pei Xi; Cheng Mengyun; Li Gui; Hu Liqin; Wu Yican; Jing Jia; Li Guoli

2011-01-01

The multi-objective optimization of inverse planning based on the Pareto solution set, according to the multi-objective character of inverse planning in accurate radiotherapy, was studied in this paper. Firstly, the clinical requirements of a treatment plan were transformed into a multi-objective optimization problem with multiple constraints. Then, the fast and elitist multi-objective Non-dominated Sorting Genetic Algorithm (NSGA-II) was introduced to optimize the problem. A clinical example was tested using this method. The results show that an obtained set of non-dominated solutions were uniformly distributed and the corresponding dose distribution of each solution not only approached the expected dose distribution, but also met the dose-volume constraints. It was indicated that the clinical requirements were better satisfied using the method and the planner could select the optimal treatment plan from the non-dominated solution set. (authors)

Association of surfactant protein-d with obesity

International Nuclear Information System (INIS)

Jawed, S.

2016-01-01

Obesity is associated with inflammatory diseases and obese individual's poses high risk for infections. Surfactant protein D (SP-D) is an important regulator of immunity and inflammation. Latest studies have suggested that it is also involved in lipid homeostasis and obese subjects have decrease concentration of SPD as compared to normal weight peoples. The aim of the current study was to elucidate the relationship among serum SP-D and BMI. Method: This cross sectional study was performed at Dow University of health sciences (DUHS), Karachi. We analysed 90 obese and non-obese subjects for serum SP-D concentration. SP-D was estimated by ELISA. Data was analysed by SPSS 16. Mean SP-D level and demographical variables between the groups were compared by t test, Associations of SP-D with BMI investigated by regression analysis. Results: obese subjects have significant lower levels of Serum SP-D than non-obese and negatively associated with BMI in both genders (p=0.000). Conclusion: This study concluded that obese subjects have lower concentration of SP-D as compare to non-obese and there is an inverse association between the SP-D and BMI. (author)

[Diagnostic Significance of BAT in Anaphylaxis to Non-ionic Contrast Media].

Science.gov (United States)

Zhang, Hao-yue; Xu, Su-jun; Tang, Xiao-xian; Niu, Ji-jun; Guo, Xiang-jie; Gao, Cai-rong

2015-06-01

To investigate the diagnostic significance of basophil activation test (BAT) in anaphylaxis to non-ionic contrast media through testing the content of CD63, mast cell-carboxypeptidase A3 (MC-CPA3), and terminal complement complex SC5b-9 of the individuals by testing their levels in the normal immune group and the anaphylaxis groups to β-lactam drugs and non -ionic contrast media. The CD63 expression of basophilic granulocyte in blood was detected by flow cytometry. The levels of MC-CPA3 in blood serum and SC5b-9 in blood plasma were detected by ELISA. The CD63 expression of basophilic granulocyte in blood, the levels of MC-CPA3 and SC5b-9 of anaphylaxis to non-ionic contrast media and β-lactam drugs were significantly higher than that in normal immune group (P contrast media. BAT can be used to diagnose the anaphylaxis to non-ionic contrast media.

Wave-equation reflection traveltime inversion

KAUST Repository

Zhang, Sanzong; Schuster, Gerard T.; Luo, Yi

2011-01-01

The main difficulty with iterative waveform inversion using a gradient optimization method is that it tends to get stuck in local minima associated within the waveform misfit function. This is because the waveform misfit function is highly nonlinear

Pesticides are Associated with Allergic and Non-Allergic Wheeze among Male Farmers

Science.gov (United States)

Hoppin, Jane A.; Umbach, David M.; Long, Stuart; London, Stephanie J.; Henneberger, Paul K.; Blair, Aaron; Alavanja, Michael; Freeman, Laura E. Beane; Sandler, Dale P.

2016-01-01

Background: Growing evidence suggests that pesticide use may contribute to respiratory symptoms. Objective: We evaluated the association of currently used pesticides with allergic and non-allergic wheeze among male farmers. Methods: Using the 2005–2010 interview data of the Agricultural Health Study, a prospective study of farmers in North Carolina and Iowa, we evaluated the association between allergic and non-allergic wheeze and self-reported use of 78 specific pesticides, reported by ≥ 1% of the 22,134 men interviewed. We used polytomous regression models adjusted for age, BMI, state, smoking, and current asthma, as well as for days applying pesticides and days driving diesel tractors. We defined allergic wheeze as reporting both wheeze and doctor-diagnosed hay fever (n = 1,310, 6%) and non-allergic wheeze as reporting wheeze but not hay fever (n = 3,939, 18%); men without wheeze were the referent. Results: In models evaluating current use of specific pesticides, 19 pesticides were significantly associated (p pyraclostrobin) had significantly different associations for allergic and non-allergic wheeze. In exposure–response models with up to five exposure categories, we saw evidence of an exposure–response relationship for several pesticides including the commonly used herbicides 2,4-D and glyphosate, the insecticides permethrin and carbaryl, and the rodenticide warfarin. Conclusions: These results for farmers implicate several pesticides that are commonly used in agricultural and residential settings with adverse respiratory effects. Citation: Hoppin JA, Umbach DM, Long S, London SJ, Henneberger PK, Blair A, Alavanja M, Beane Freeman LE, Sandler DP. 2017. Pesticides are associated with allergic and non-allergic wheeze among male farmers. Environ Health Perspect 125:535–543; http://dx.doi.org/10.1289/EHP315 PMID:27384423

Polymorphism in COX-2 modifies the inverse association between Helicobacter pylori seropositivity and esophageal squamous cell carcinoma risk in Taiwan: a case control study

Directory of Open Access Journals (Sweden)

Lee Jang-Ming

2009-05-01

Full Text Available Abstract Background Overexpression of Cyclooxygenase-2 (COX-2 was observed in many types of cancers, including esophageal squamous cell carcinoma (ESCC. One functional SNP, COX-2 -1195G/A, has been reported to mediate susceptibility of ESCC in Chinese populations. In our previous study, the presence of Helicobacter pylori (H. pylori was found to play a protective role in development of ESCC. The interaction of COX-2 and H. pylori in gastric cancer was well investigated. However, literature on their interaction in ESCC risk is scarce. The purpose of this study was to evaluate the association and interaction between COX-2 single nucleotide polymorphism (SNP, H. pylori infection and the risk of developing ESCC. Methods One hundred and eighty patients with ESCC and 194 controls were enrolled in this study. Personal data regarding related risk factors, including alcohol consumption, smoking habits and betel quid chewing, were collected via questionnaire. Genotypes of the COX-2 -1195 polymorphism were determined by PCR-based restriction fragment length polymorphism. H. pylori seropositivity was defined by immunochromatographic screening test. Data was analyzed by chi-squared tests and polytomous logistics regression. Results In analysis adjusting for the covariates and confounders, H. pylori seropositivity was found to be inversely association with the ESCC development (adjusted OR: 0.5, 95% CI: 0.3 – 0.9. COX-2 -1195 AA homozygous was associated with an increased risk of contracting ESCC in comparison with the non-AA group, especially among patients with H. pylori seronegative (adjusted OR ratio: 2.9, 95% CI: 1.2 – 7.3. The effect was strengthened among patients with lower third ESCC (adjusted OR ratio: 6.9, 95% CI 2.1 – 22.5. Besides, H. pylori seropositivity conveyed a notably inverse effect among patients with COX-2 AA polymorphism (AOR ratio: 0.3, 95% CI: 0.1 – 0.9, and the effect was observed to be enhanced for the lower third ESCC

Intersections, ideals, and inversion

International Nuclear Information System (INIS)

Vasco, D.W.

1998-01-01

Techniques from computational algebra provide a framework for treating large classes of inverse problems. In particular, the discretization of many types of integral equations and of partial differential equations with undetermined coefficients lead to systems of polynomial equations. The structure of the solution set of such equations may be examined using algebraic techniques.. For example, the existence and dimensionality of the solution set may be determined. Furthermore, it is possible to bound the total number of solutions. The approach is illustrated by a numerical application to the inverse problem associated with the Helmholtz equation. The algebraic methods are used in the inversion of a set of transverse electric (TE) mode magnetotelluric data from Antarctica. The existence of solutions is demonstrated and the number of solutions is found to be finite, bounded from above at 50. The best fitting structure is dominantly one dimensional with a low crustal resistivity of about 2 ohm-m. Such a low value is compatible with studies suggesting lower surface wave velocities than found in typical stable cratons

Intersections, ideals, and inversion

Energy Technology Data Exchange (ETDEWEB)

Vasco, D.W.

1998-10-01

Techniques from computational algebra provide a framework for treating large classes of inverse problems. In particular, the discretization of many types of integral equations and of partial differential equations with undetermined coefficients lead to systems of polynomial equations. The structure of the solution set of such equations may be examined using algebraic techniques.. For example, the existence and dimensionality of the solution set may be determined. Furthermore, it is possible to bound the total number of solutions. The approach is illustrated by a numerical application to the inverse problem associated with the Helmholtz equation. The algebraic methods are used in the inversion of a set of transverse electric (TE) mode magnetotelluric data from Antarctica. The existence of solutions is demonstrated and the number of solutions is found to be finite, bounded from above at 50. The best fitting structure is dominantly onedimensional with a low crustal resistivity of about 2 ohm-m. Such a low value is compatible with studies suggesting lower surface wave velocities than found in typical stable cratons.

Novel loci and pathways significantly associated with longevity

DEFF Research Database (Denmark)

Zeng, Yi; Nie, Chao; Min, Junxia

2016-01-01

Only two genome-wide significant loci associated with longevity have been identified so far, probably because of insufficient sample sizes of centenarians, whose genomes may harbor genetic variants associated with health and longevity. Here we report a genome-wide association study (GWAS) of Han ...

Trimming and procrastination as inversion techniques

Science.gov (United States)

Backus, George E.

1996-12-01

By examining the processes of truncating and approximating the model space (trimming it), and by committing to neither the objectivist nor the subjectivist interpretation of probability (procrastinating), we construct a formal scheme for solving linear and non-linear geophysical inverse problems. The necessary prior information about the correct model xE can be either a collection of inequalities or a probability measure describing where xE was likely to be in the model space X before the data vector y0 was measured. The results of the inversion are (1) a vector z0 that estimates some numerical properties zE of xE; (2) an estimate of the error δz = z0 - zE. As y0 is finite dimensional, so is z0, and hence in principle inversion cannot describe all of xE. The error δz is studied under successively more specialized assumptions about the inverse problem, culminating in a complete analysis of the linear inverse problem with a prior quadratic bound on xE. Our formalism appears to encompass and provide error estimates for many of the inversion schemes current in geomagnetism, and would be equally applicable in geodesy and seismology if adequate prior information were available there. As an idealized example we study the magnetic field at the core-mantle boundary, using satellite measurements of field elements at sites assumed to be almost uniformly distributed on a single spherical surface. Magnetospheric currents are neglected and the crustal field is idealized as a random process with rotationally invariant statistics. We find that an appropriate data compression diagonalizes the variance matrix of the crustal signal and permits an analytic trimming of the idealized problem.

Chocolate consumption is inversely associated with prevalent coronary heart disease: the National Heart, Lung, and Blood Institute Family Heart Study.

Science.gov (United States)

Djoussé, Luc; Hopkins, Paul N; North, Kari E; Pankow, James S; Arnett, Donna K; Ellison, R Curtis

2011-04-01

Epidemiologic studies have suggested beneficial effects of flavonoids on cardiovascular disease. Cocoa and particularly dark chocolate are rich in flavonoids and recent studies have demonstrated blood pressure lowering effects of dark chocolate. However, limited data are available on the association of chocolate consumption and the risk of coronary heart disease (CHD). We sought to examine the association between chocolate consumption and prevalent CHD. We studied in a cross-sectional design 4970 participants aged 25-93 years who participated in the National Heart, Lung, and Blood Institute (NHLBI) Family Heart Study. Chocolate intake was assessed through a semi-quantitative food frequency questionnaire. We used generalized estimating equations to estimate adjusted odds ratios. Compared to subjects who did not report any chocolate intake, odds ratios (95% CI) for CHD were 1.01 (0.76-1.37), 0.74 (0.56-0.98), and 0.43 (0.28-0.67) for subjects consuming 1-3 times/month, 1-4 times/week, and 5+ times/week, respectively (p for trend Consumption of non-chocolate candy was associated with a 49% higher prevalence of CHD comparing 5+/week vs. 0/week [OR = 1.49 (0.96-2.32)]. These data suggest that consumption of chocolate is inversely related with prevalent CHD in a general United States population. Published by Elsevier Ltd.

Nested Inversion Polymorphisms Predispose Chromosome 22q11.2 to Meiotic Rearrangements

NARCIS (Netherlands)

Demaerel, Wolfram; Hestand, Matthew S.; Vergaelen, Elfi; Swillen, Ann; López-Sánchez, Marcos; Pérez-Jurado, Luis A.; McDonald-Mcginn, Donna M.; Zackai, Elaine; Emanuel, Beverly S.; Morrow, Bernice E.; Breckpot, Jeroen; Devriendt, Koenraad; Vermeesch, Joris R.; Antshel, Kevin M.; Arango, Celso; Armando, Marco; Bassett, Anne S.; Bearden, Carrie E.; Boot, Erik; Bravo-Sanchez, Marta; Breetvelt, Elemi; Busa, Tiffany; Butcher, Nancy J.; Campbell, Linda E.; Carmel, Miri; Chow, Eva W C; Crowley, T. Blaine; Cubells, Joseph; Cutler, David; Demaerel, Wolfram; Digilio, Maria Cristina; Duijff, Sasja; Eliez, Stephan; Emanuel, Beverly S.; Epstein, Michael P.; Evers, Rens; Fernandez Garcia-Moya, Luis; Fiksinski, Ania; Fraguas, David; Fremont, Wanda; Fritsch, Rosemarie; Garcia-Minaur, Sixto; Golden, Aaron; Gothelf, Doron; Guo, Tingwei; Gur, Ruben C.; Gur, Raquel E.; Heine-Suner, Damian; Hestand, Matthew; Hooper, Stephen R.; Kates, Wendy R.; Kushan, Leila; Laorden-Nieto, Alejandra; Maeder, Johanna; Marino, Bruno; Marshall, Christian R.; McCabe, Kathryn; McDonald-Mcginn, Donna M.; Michaelovosky, Elena; Morrow, Bernice E.; Moss, Edward; Mulle, Jennifer; Murphy, Declan; Murphy, Kieran C.; Murphy, Clodagh M.; Niarchou, Maria; Ornstein, Claudia; Owen, Michael J; Philip, Nicole; Repetto, Gabriela M.; Schneider, Maude; Shashi, Vandana; Simon, Tony J.; Swillen, Ann; Tassone, Flora; Unolt, Marta; Van Amelsvoort, Therese; van den Bree, Marianne B M; Van Duin, Esther; Vergaelen, Elfi; Vermeesch, Joris R.; Vicari, Stefano; Vingerhoets, Claudia; Vorstman, Jacob; Warren, Steve; Weinberger, Ronnie; Weisman, Omri; Weizman, Abraham; Zackai, Elaine; Zhang, Zhengdong; Zwick, Michael

2017-01-01

Inversion polymorphisms between low-copy repeats (LCRs) might predispose chromosomes to meiotic non-allelic homologous recombination (NAHR) events and thus lead to genomic disorders. However, for the 22q11.2 deletion syndrome (22q11.2DS), the most common genomic disorder, no such inversions have

Inverse association of natural mentoring relationship with distress mental health in children orphaned by AIDS

Directory of Open Access Journals (Sweden)

Munakata Tsunetsugu

2010-01-01

Full Text Available Abstract Background The magnitude of the AIDS-orphaned children crisis in sub-Saharan Africa has so overstretched the resource of most families that the collapse of fostering in the sub-region seems imminent (UNICEF, 2003, fueling the need for a complementary/alternative care. This paper examines the probability of the natural mentoring care to ameliorate distress mental health in children orphaned by AIDS. Methods 952 children, mean age about 14 years, from local community schools and child-care centers in Kampala (Uganda and Mafikeng/Klerksdorp (South Africa towns participated in the study. The design has AIDS-orphaned group (n = 373 and two control groups: Other-causes orphaned (n = 287 and non-orphaned (n = 290 children. We use measures of child abuse, depression, social discrimination, anxiety, parental/foster care, self-esteem, and social support to estimate mental health. Natural mentoring care is measured with the Ragins and McFarlin (1990 Mentor Role Instrument as adapted. Results AIDS-orphaned children having a natural mentor showed significant decreased distress mental health factors. Similar evidence was not observed in the control groups. Also being in a natural mentoring relationship inversely related to distress mental health factors in the AIDS-orphaned group, in particular. AIDS-orphaned children who scored high mentoring relationship showed significant lowest distress mental health factors that did those who scored moderate and low mentoring relationship. Conclusions Natural mentoring care seems more beneficial to ameliorate distress mental health in AIDS-orphaned children (many of whom are double-orphans, having no biological parents than in children in the control groups.

Lymphoproliferative disorders in non-AIDS associated Kaposi's ...

African Journals Online (AJOL)

The association of the non-AIDS-related, classic fonn of Kaposi's sarcoma (KS) with secondary malignancies, especially Iymphoproliferative disorders, has frequently been noted. However, in endemic: African-type KS, such an association has been reported only rarely. A review of 62 non-AIDS-related cases of KS treated ...

A three-dimensional gravity inversion applied to São Miguel Island (Azores)

Science.gov (United States)

Camacho, A. G.; Montesinos, F. G.; Vieira, R.

1997-04-01

Gravimetric studies are becoming more and more widely acknowledged as a useful tool for studying and modeling the distributions of subsurface masses that are associated with volcanic activity. In this paper, new gravimetric data for the volcanic island of São Miguel (Azores) were analyzed and interpreted by a stabilized linear inversion methodology. An inversion model of higher resolution was calculated for the Caldera of Furnas, which has a larger density of data. In order to filter out the noncorrelatable anomalies, least squares prediction was used, resulting in a correlated gravimetric signal model with an accuracy of the order of 0.9 mGal. The gravimetric inversion technique is based on the adjustment of a three-dimensional (3-D) model of cubes of unknown density that represents the island's subsurface. The problem of non-uniqueness is solved by minimization with appropriate covariance matrices of the data (resulting from the least squares prediction) and of the unknowns. We also propose a criterion for choosing a balance between the data fit (which in this case corresponds to residues with rms of the order of 0.6 mGal) and the smoothness of the solution. The global model of the island includes a low-density zone in a WNW-ESE direction and a depth of the order of 20 km, associated with the Terceira rift spreading center. The minimums located at a depth of 4 km may be associated with shallow magmatic chambers beneath the main volcanoes of the island. The main high-density area is related to the Nordeste basaltic shield. With regard to the Caldera Furnas, in addition to the minimum that can be associated with a magmatic chamber, there are other shallow minimums that correspond to eruptive processes.

Single- and coupled-channel radial inverse scattering with supersymmetric transformations

International Nuclear Information System (INIS)

Baye, Daniel; Sparenberg, Jean-Marc; Pupasov-Maksimov, Andrey M; Samsonov, Boris F

2014-01-01

The present status of the three-dimensional inverse-scattering method with supersymmetric transformations is reviewed for the coupled-channel case. We first revisit in a pedagogical way the single-channel case, where the supersymmetric approach is shown to provide a complete, efficient and elegant solution to the inverse-scattering problem for the radial Schrödinger equation with short-range interactions. A special emphasis is put on the differences between conservative and non-conservative transformations, i.e. transformations that do or do not conserve the behaviour of solutions of the radial Schrödinger equation at the origin. In particular, we show that for the zero initial potential, a non-conservative transformation is always equivalent to a pair of conservative transformations. These single-channel results are illustrated on the inversion of the neutron–proton triplet eigenphase shifts for the S- and D-waves. We then summarize and extend our previous works on the coupled-channel case, i.e. on systems of coupled radial Schrödinger equations, and stress remaining difficulties and open questions of this problem by putting it in perspective with the single-channel case. We mostly concentrate on two-channel examples to illustrate general principles while keeping mathematics as simple as possible. In particular, we discuss the important difference between the equal-threshold and different-threshold problems. For equal thresholds, conservative transformations can provide non-diagonal Jost and scattering matrices. Iterations of such transformations in the two-channel case are studied and shown to lead to practical algorithms for inversion. A convenient particular technique where the mixing parameter can be fitted without modifying the eigenphases is developed with iterations of pairs of conjugate transformations. This technique is applied to the neutron–proton triplet S–D scattering matrix, for which exactly-solvable matrix potential models are constructed

Output Tracking for Systems with Non-Hyperbolic and Near Non-Hyperbolic Internal Dynamics: Helicopter Hover Control

Science.gov (United States)

Devasia, Santosh

1996-01-01

A technique to achieve output tracking for nonminimum phase linear systems with non-hyperbolic and near non-hyperbolic internal dynamics is presented. This approach integrates stable inversion techniques, that achieve exact-tracking, with approximation techniques, that modify the internal dynamics to achieve desirable performance. Such modification of the internal dynamics is used (1) to remove non-hyperbolicity which an obstruction to applying stable inversion techniques and (2) to reduce large pre-actuation time needed to apply stable inversion for near non-hyperbolic cases. The method is applied to an example helicopter hover control problem with near non-hyperbolic internal dynamic for illustrating the trade-off between exact tracking and reduction of pre-actuation time.

Efficient Stochastic Inversion Using Adjoint Models and Kernel-PCA

Energy Technology Data Exchange (ETDEWEB)

Thimmisetty, Charanraj A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States). Center for Applied Scientific Computing; Zhao, Wenju [Florida State Univ., Tallahassee, FL (United States). Dept. of Scientific Computing; Chen, Xiao [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States). Center for Applied Scientific Computing; Tong, Charles H. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States). Center for Applied Scientific Computing; White, Joshua A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States). Atmospheric, Earth and Energy Division

2017-10-18

Performing stochastic inversion on a computationally expensive forward simulation model with a high-dimensional uncertain parameter space (e.g. a spatial random field) is computationally prohibitive even when gradient information can be computed efficiently. Moreover, the ‘nonlinear’ mapping from parameters to observables generally gives rise to non-Gaussian posteriors even with Gaussian priors, thus hampering the use of efficient inversion algorithms designed for models with Gaussian assumptions. In this paper, we propose a novel Bayesian stochastic inversion methodology, which is characterized by a tight coupling between the gradient-based Langevin Markov Chain Monte Carlo (LMCMC) method and a kernel principal component analysis (KPCA). This approach addresses the ‘curse-of-dimensionality’ via KPCA to identify a low-dimensional feature space within the high-dimensional and nonlinearly correlated parameter space. In addition, non-Gaussian posterior distributions are estimated via an efficient LMCMC method on the projected low-dimensional feature space. We will demonstrate this computational framework by integrating and adapting our recent data-driven statistics-on-manifolds constructions and reduction-through-projection techniques to a linear elasticity model.

Inverse U-shaped Association between Sleep Duration and Semen Quality: Longitudinal Observational Study (MARHCS) in Chongqing, China

Science.gov (United States)

Chen, Qing; Yang, Huan; Zhou, Niya; Sun, Lei; Bao, Huaqiong; Tan, Lu; Chen, Hongqiang; Ling, Xi; Zhang, Guowei; Huang, Linping; Li, Lianbing; Ma, Mingfu; Yang, Hao; Wang, Xiaogang; Zou, Peng; Peng, Kaige; Liu, Taixiu; Cui, Zhihong; Ao, Lin; Roenneberg, Till; Zhou, Ziyuan; Cao, Jia

2016-01-01

Study Objectives: To investigate the association between sleep duration and semen parameters as well as reproductive hormone levels. Methods: We designed a cohort of male college students in Chongqing, China. A total of 796 subjects were recruited in 2013 and 656 (82.4%) were followed up in 2014. Each time, semen and peripheral blood samples were collected for semen quality and reproductive hormone measurement. Sleep duration was estimated by revised Munich Chronotype Questionnaire. In 2014, sleep quality was also measured by Pittsburgh Sleep Quality Index (PSQI). Results: There was a substantial inverse U-shaped association between sleep duration and two semen parameters (semen volume and total sperm number), with 7.0–7.5 h/day of sleep showing highest parameters. Either longer or shorter sleep was associated with decreased semen parameters in a dose-response manner (P = 0.002 and 0.001, respectively). Sleeping > 9.0 h was associated with a 21.5% (95% confidence interval 9.2, 32.2) reduction in semen volume and 39.4% (23.3, 52.1) reduction in total sperm number; sleeping ≤ 6.5 h was associated with 4.6% (−10.5, 22.3) and 25.7% (−1.2, 60.1) reduction. Increase of the two parameters was found in those who changed sleep duration toward 7.0–7.5 h/day from 2013 to 2014. The U-shaped association was independent from PSQI and was replicated in another dataset of 1,346 males. No association found between sleep duration and reproductive hormone. Conclusions: Either restricted or excessive sleep may impair semen quality. Further research is needed to validate this finding. Citation: Chen Q, Yang H, Zhou N, Sun L, Bao H, Tan L, Chen H, Ling X, Zhang G, Huang L, Li L, Ma M, Yang H, Wang X, Zou P, Peng K, Liu T, Cui Z, Ao L, Roenneberg T, Zhou Z, Cao J. Inverse u-shaped association between sleep duration and semen quality: longitudinal observational study (MARHCS) in Chongqing, China. SLEEP 2016;39(1):79–86. PMID:26350472

Inverse problems in vision and 3D tomography

CERN Document Server

Mohamad-Djafari, Ali

2013-01-01

The concept of an inverse problem is a familiar one to most scientists and engineers, particularly in the field of signal and image processing, imaging systems (medical, geophysical, industrial non-destructive testing, etc.) and computer vision. In imaging systems, the aim is not just to estimate unobserved images, but also their geometric characteristics from observed quantities that are linked to these unobserved quantities through the forward problem. This book focuses on imagery and vision problems that can be clearly written in terms of an inverse problem where an estimate for the image a

Intake of Specific Nonfermented Soy Foods May Be Inversely Associated with Risk of Distal Gastric Cancer in a Chinese Population123

Science.gov (United States)

Kweon, Sun-Seog; Shu, Xiao-Ou; Xiang, Yongbing; Cai, Hui; Yang, Gong; Ji, Bu-Tian; Li, Honglan; Gao, Yu-Tang; Zheng, Wei; Epplein, Meira

2013-01-01

Because the association between soy consumption and gastric cancer is inconsistent, we evaluated the putative preventive effect of soy food on gastric cancer risk in the Shanghai Women’s and Men’s Health Studies, comprising a total of 128,687 participants. Intake of nonfermented soy foods was estimated using 2 validated food-frequency questionnaires. HRs were calculated with 95% CIs for intake amounts of total nonfermented soy food intake, soy protein, and isoflavones as well as individual soy food groups using Cox proportional hazards regression. A total of 493 distal gastric cancer cases were identified by 2010. Although all risk estimates for summary measures of soy food intake above the lowest quartile (quartile 1) were suggestive of a protective effect, no statistically significant associations with risk of distal gastric cancer were found. Among the separate soy food groups, significant reductions in risk of distal gastric cancer by increasing intake of tofu were found in men in quartile 2 (HR: 0.59; 95% CI: 0.40, 0.86), quartile 3 (HR: 0.62; 95% CI: 0.44, 0.88), and quartile 4 (HR: 0.64; 95% CI: 0.42, 0.99), resulting in a significant trend (P-trend = 0.02). Dry bean intake was also inversely associated with decreased risk of gastric cancer, but in postmenopausal women only [quartile 2 (HR: 0.54; 95% CI: 0.30, 0.96); quartile 3 (HR: 0.90; 95% CI: 0.64, 1.27); and quartile 4 (HR: 0.63; 95% CI: 0.43, 0.91)], resulting in a significant trend (P-trend = 0.03). Overall, our study found no statistically significant association between nonfermented soy food intake and distal gastric cancer risk, though the data supported the hypothesis that tofu may protect against distal gastric cancer in men and dry bean consumption may decrease the risk of gastric cancer in postmenopausal women. PMID:23986366

High consumption of vegetable and fruit colour groups is inversely associated with the risk of colorectal cancer: a case-control study.

Science.gov (United States)

Luo, Wei-Ping; Fang, Yu-Jing; Lu, Min-Shan; Zhong, Xiao; Chen, Yu-Ming; Zhang, Cai-Xia

2015-04-14

The colour of the edible portion of vegetables and fruit reflects the presence of specific micronutrients and phytochemicals. No existing studies have examined the relationship between the intake of vegetable and fruit colour groups and the risk of colorectal cancer. The present study, therefore, aimed to investigate these associations in a Chinese population. A case-control study was conducted between July 2010 and July 2014 in Guangzhou, China, in which 1057 consecutively recruited cases of colorectal cancer were frequency-matched to 1057 controls by age (5-year interval), sex and residence (rural/urban). A validated FFQ was used to collect dietary information during face-to-face interviews. Vegetables and fruit were classified into four groups according to the colour of their primarily edible parts: green; orange/yellow; red/purple; white. Unconditional logistic regression models were used to estimate the OR and 95 % CI. A higher consumption of orange/yellow, red/purple and white vegetables and fruit was inversely associated with the risk of colorectal cancer, with adjusted OR of 0·16 (95 % CI 0·12, 0·22) for orange/yellow, 0·23 (95 % CI 0·17, 0·31) for red/purple and 0·53 (95 % CI 0·40, 0·70) for white vegetables and fruit when the highest and lowest quartiles were compared. Total vegetable intake and total fruit intake have also been found to be inversely associated with colorectal cancer risk. However, the intake of green vegetable and fruit was not associated with colorectal cancer risk. The results of the present study, therefore, suggest that a greater intake of orange/yellow, red/purple and white vegetables and fruit is inversely associated with the risk of colorectal cancer.

Automatic associations with the sensory aspects of smoking: Positive in habitual smokers but negative in non-smokers

OpenAIRE

Huijding, Jorg; Jong, Peter

2006-01-01

textabstractTo test whether pictorial stimuli that focus on the sensory aspects of smoking elicit different automatic affective associations in smokers than in non-smokers, 31 smoking and 33 non-smoking students completed a single target IAT. Explicit attitudes were assessed using a semantic differential. Automatic affective associations were positive in smokers but negative in non-smokers. Only automatic affective associations but not self-reported attitudes were significantly correlated wit...

Syrio. A program for the calculation of the inverse of a matrix

International Nuclear Information System (INIS)

Garcia de Viedma Alonso, L.

1963-01-01

SYRIO is a code for the inversion of a non-singular square matrix whose order is not higher than 40 for the UNIVAC-UCT (SS-90). The treatment stands from the inversion formula of sherman and Morrison, and following the Herbert S. Wilf's method for special matrices, generalize the procedure to any kind of non-singular square matrices. the limitation of the matrix order is not inherent of the program itself but imposed by the storage capacity of the computer for which it was coded. (Author)

ANNIT - An Efficient Inversion Algorithm based on Prediction Principles

Science.gov (United States)

Růžek, B.; Kolář, P.

2009-04-01

Solution of inverse problems represents meaningful job in geophysics. The amount of data is continuously increasing, methods of modeling are being improved and the computer facilities are also advancing great technical progress. Therefore the development of new and efficient algorithms and computer codes for both forward and inverse modeling is still up to date. ANNIT is contributing to this stream since it is a tool for efficient solution of a set of non-linear equations. Typical geophysical problems are based on parametric approach. The system is characterized by a vector of parameters p, the response of the system is characterized by a vector of data d. The forward problem is usually represented by unique mapping F(p)=d. The inverse problem is much more complex and the inverse mapping p=G(d) is available in an analytical or closed form only exceptionally and generally it may not exist at all. Technically, both forward and inverse mapping F and G are sets of non-linear equations. ANNIT solves such situation as follows: (i) joint subspaces {pD, pM} of original data and model spaces D, M, resp. are searched for, within which the forward mapping F is sufficiently smooth that the inverse mapping G does exist, (ii) numerical approximation of G in subspaces {pD, pM} is found, (iii) candidate solution is predicted by using this numerical approximation. ANNIT is working in an iterative way in cycles. The subspaces {pD, pM} are searched for by generating suitable populations of individuals (models) covering data and model spaces. The approximation of the inverse mapping is made by using three methods: (a) linear regression, (b) Radial Basis Function Network technique, (c) linear prediction (also known as "Kriging"). The ANNIT algorithm has built in also an archive of already evaluated models. Archive models are re-used in a suitable way and thus the number of forward evaluations is minimized. ANNIT is now implemented both in MATLAB and SCILAB. Numerical tests show good

The incorporation of SPECT functional lung imaging into inverse radiotherapy planning for non-small cell lung cancer

International Nuclear Information System (INIS)

Christian, Judith A.; Partridge, Mike; Nioutsikou, Elena; Cook, Gary; McNair, Helen A.; Cronin, Bernadette; Courbon, Frederic; Bedford, James L.; Brada, Michael

2005-01-01

Background and purpose: Patients with non-small cell lung cancer (NSCLC) often have inhomogeneous lung perfusion. Radiotherapy planning computed tomography (CT) scans have been accurately co-registered with lung perfusion single photon emission computed tomography (SPECT) scans to design radiotherapy treatments which limit dose to healthy 'perfused' lung. Patients and methods: Patients with localised NSCLC had CT and SPECT scans accurately co-registered in the planning system. The SPECT images were used to define a volume of perfused 'functioning' lung (FL). Inverse planning software was used to create 3D-conformal plans, the planning objective being either to minimise the dose to whole lungs (WL) or to minimise the dose to FL. Results: Four plans were created for each of six patients. The mean difference in volume between WL and FL was 1011.7 cm 3 (range 596.2-1581.1 cm 3 ). One patient with bilateral upper lobe perfusion deficits had a 16% reduction in FLV 2 (the percentage volume of functioning lung receiving ≥20 Gy). The remaining patients had inhomogeneous perfusion deficits such that inverse planning was not able to sufficiently optimise beam angles to avoid functioning lung. Conclusion: SPECT perfusion images can be accurately co-registered with radiotherapy planning CT scans and may be helpful in creating treatment plans for patients with large perfusion deficits

Quantum osp-invariant non-linear Schroedinger equation

International Nuclear Information System (INIS)

Kulish, P.P.

1985-04-01

The generalizations of the non-linear Schroedinger equation (NS) associated with the orthosymplectic superalgebras are formulated. The simplest osp(1/2)-NS model is solved by the quantum inverse scattering method on a finite interval under periodic boundary conditions as well as on the wholeline in the case of a finite number of excitations. (author)

Kinematic inversion of the 2008 Mw7 Iwate-Miyagi (Japan) earthquake by two independent methods: Sensitivity and resolution analysis

Science.gov (United States)

Gallovic, Frantisek; Cirella, Antonella; Plicka, Vladimir; Piatanesi, Alessio

2013-04-01

On 14 June 2008, UTC 23:43, the border of Iwate and Miyagi prefectures was hit by an Mw7 reverse-fault type crustal earthquake. The event is known to have the largest ground acceleration observed to date (~4g), which was recorded at station IWTH25. We analyze observed strong motion data with the objective to image the event rupture process and the associated uncertainties. Two different slip inversion approaches are used, the difference between the two methods being only in the parameterization of the source model. To minimize mismodeling of the propagation effects we use crustal model obtained by full waveform inversion of aftershock records in the frequency range between 0.05-0.3 Hz. In the first method, based on linear formulation, the parameters are represented by samples of slip velocity functions along the (finely discretized) fault in a time window spanning the whole rupture duration. Such a source description is very general with no prior constraint on the nucleation point, rupture velocity, shape of the velocity function. Thus the inversion could resolve very general (unexpected) features of the rupture evolution, such as multiple rupturing, rupture-propagation reversals, etc. On the other hand, due to the relatively large number of model parameters, the inversion result is highly non-unique, with possibility of obtaining a biased solution. The second method is a non-linear global inversion technique, where each point on the fault can slip only once, following a prescribed functional form of the source time function. We invert simultaneously for peak slip velocity, slip angle, rise time and rupture time by allowing a given range of variability for each kinematic model parameter. For this reason, unlike to the linear inversion approach, the rupture process needs a smaller number of parameters to be retrieved, and is more constrained with a proper control on the allowed range of parameter values. In order to test the resolution and reliability of the

Birth order and risk of non-hodgkin lymphoma--true association or bias?

Science.gov (United States)

Grulich, Andrew E; Vajdic, Claire M; Falster, Michael O; Kane, Eleanor; Smedby, Karin Ekstrom; Bracci, Paige M; de Sanjose, Silvia; Becker, Nikolaus; Turner, Jenny; Martinez-Maza, Otoniel; Melbye, Mads; Engels, Eric A; Vineis, Paolo; Costantini, Adele Seniori; Holly, Elizabeth A; Spinelli, John J; La Vecchia, Carlo; Zheng, Tongzhang; Chiu, Brian C H; Franceschi, Silvia; Cocco, Pierluigi; Maynadié, Marc; Foretova, Lenka; Staines, Anthony; Brennan, Paul; Davis, Scott; Severson, Richard K; Cerhan, James R; Breen, Elizabeth C; Birmann, Brenda; Cozen, Wendy

2010-09-15

There is inconsistent evidence that increasing birth order may be associated with risk of non-Hodgkin lymphoma (NHL). The authors examined the association between birth order and related variables and NHL risk in a pooled analysis (1983-2005) of 13,535 cases and 16,427 controls from 18 case-control studies within the International Lymphoma Epidemiology Consortium (InterLymph). Overall, the authors found no significant association between increasing birth order and risk of NHL (P-trend = 0.082) and significant heterogeneity. However, a significant association was present for a number of B- and T-cell NHL subtypes. There was considerable variation in the study-specific risks which was partly explained by study design and participant characteristics. In particular, a significant positive association was present in population-based studies, which had lower response rates in cases and controls, but not in hospital-based studies. A significant positive association was present in higher-socioeconomic-status (SES) participants only. Results were very similar for the related variable of sibship size. The known correlation of high birth order with low SES suggests that selection bias related to SES may be responsible for the association between birth order and NHL.

Soluble CD163, a product of monocyte/macrophage activation, is inversely associated with haemoglobin levels in placental malaria.

Directory of Open Access Journals (Sweden)

Caroline Lin Lin Chua

Full Text Available In Plasmodium falciparum malaria, activation of monocytes and macrophages (monocytes/macrophages can result in the production of various inflammatory mediators that contribute to immunopathology. Soluble CD163 (sCD163 is a specific marker of monocyte/macrophage activation typically found at increased levels during various inflammatory conditions and can be associated with poor clinical outcomes. To better understand the relationships between levels of sCD163 and clinical parameters in women with placental malaria, we measured plasma sCD163 levels in maternal peripheral and placental blood compartments at delivery and determined their correlations with birth weight and maternal haemoglobin concentrations. sCD163 levels were negatively correlated with birth weight only in the placental compartment (r = -0.145, p = 0.03 and were inversely correlated with maternal haemoglobin concentrations, both in peripheral blood (r = -0.238, p = 0.0004 and in placental blood (r = -0.259, p = 0.0001. These inverse relationships suggest a potential role for monocyte/macrophage activation in the pathogenesis of malaria in pregnancy, particularly in relation to malaria-associated anaemia.

Recombination and synaptic adjustment in oocytes of mice heterozygous for a large paracentric inversion.

Science.gov (United States)

Torgasheva, Anna A; Rubtsov, Nikolai B; Borodin, Pavel M

2013-03-01

Homologous chromosome synapsis in inversion heterozygotes results in the formation of inversion loops. These loops might be transformed into straight, non-homologously paired bivalents via synaptic adjustment. Synaptic adjustment was discovered 30 years ago; however, its relationship with recombination has remained unclear. We analysed this relationship in female mouse embryos heterozygous for large paracentric inversion In(1)1Rk using immunolocalisation of the synaptonemal complex (SYCP3) and mature recombination nodules (MLH1) proteins. The frequency of cells containing bivalents with inversion loops decreased from 69 % to 28 % during pachytene. If an MLH1 focus was present in the non-homologously paired inverted region of the straight bivalent, it was always located in the middle of the inversion. Most of the small, incompletely adjusted loops contained MLH1 foci near the points at which pairing partners were switched. This observation indicates that the degree of synaptic adjustment depended on the crossover position. Complete synaptic adjustment was only possible if a crossover (CO) was located exactly in the middle of the inversion. If a CO was located at any other site, this interrupted synaptic adjustment and resulted in inversion loops of different sizes with an MLH1 focus at or near the edge of the remaining loop.

Children's strategies to solving additive inverse problems: a preliminary analysis

Science.gov (United States)

Ding, Meixia; Auxter, Abbey E.

2017-03-01

Prior studies show that elementary school children generally "lack" formal understanding of inverse relations. This study goes beyond lack to explore what children might "have" in their existing conception. A total of 281 students, kindergarten to third grade, were recruited to respond to a questionnaire that involved both contextual and non-contextual tasks on inverse relations, requiring both computational and explanatory skills. Results showed that children demonstrated better performance in computation than explanation. However, many students' explanations indicated that they did not necessarily utilize inverse relations for computation. Rather, they appeared to possess partial understanding, as evidenced by their use of part-whole structure, which is a key to understanding inverse relations. A close inspection of children's solution strategies further revealed that the sophistication of children's conception of part-whole structure varied in representation use and unknown quantity recognition, which suggests rich opportunities to develop students' understanding of inverse relations in lower elementary classrooms.

Postmeal increment in intact glucagon-like peptide 1 level, but not intact glucose-dependent insulinotropic polypeptide levels, is inversely associated with metabolic syndrome in patients with type 2 diabetes.

Science.gov (United States)

Yoo, Soyeon; Yang, Eun-Jin; Lee, Sang Ah; Koh, Gwanpyo

2018-02-01

Metabolic syndrome increases the risk of cardiovascular disease. Recently glucagon-like peptide 1 (GLP-1) agonists proved to be effective in preventing cardiovascular disease (CVD) in patients with type 2 diabetes. We investigated the association of blood incretin levels with metabolic syndrome in patients with type 2 diabetes. This is a cross-sectional study involving 334 people with type 2 diabetes. Intact GLP-1 (iGLP-1) and intact glucose-dependent insulinotropic polypeptide (iGIP) levels were measured in a fasted state and 30 min after ingestion of a standard mixed meal. Metabolic syndrome was diagnosed based on the criteria of the International Diabetes Federation. Two hundred twenty-five (69%) of the subjects have metabolic syndrome. The fasting iGLP-1 level was no different between groups. Thirty-min postprandial iGLP-1 was non-significantly lower in the subjects who had metabolic syndrome. Incremental iGLP-1 (ΔiGLP-1, the difference between 30-min postmeal and fasting iGLP-1 levels) was significantly lower in those with metabolic syndrome. There were no significant differences in fasting iGIP, postprandial iGIP, and ΔiGIP between groups. The ΔiGLP-1, but not ΔiGIP levels decreased significantly as the number of metabolic syndrome components increased. In hierarchical logistic regression analysis, the ΔiGLP-1 level was found to be a significant contributor to metabolic syndrome even after adjusting for other covariates. Taken together, the iGLP-1 increment in the 30 min after meal ingestion is inversely associated with metabolic syndrome in patients with type 2 diabetes. This suggests that postmeal iGLP-1 increment could be useful in assessing cardiovascular risk in type 2 diabetes.

3D CSEM inversion based on goal-oriented adaptive finite element method

Science.gov (United States)

Zhang, Y.; Key, K.

2016-12-01

We present a parallel 3D frequency domain controlled-source electromagnetic inversion code name MARE3DEM. Non-linear inversion of observed data is performed with the Occam variant of regularized Gauss-Newton optimization. The forward operator is based on the goal-oriented finite element method that efficiently calculates the responses and sensitivity kernels in parallel using a data decomposition scheme where independent modeling tasks contain different frequencies and subsets of the transmitters and receivers. To accommodate complex 3D conductivity variation with high flexibility and precision, we adopt the dual-grid approach where the forward mesh conforms to the inversion parameter grid and is adaptively refined until the forward solution converges to the desired accuracy. This dual-grid approach is memory efficient, since the inverse parameter grid remains independent from fine meshing generated around the transmitter and receivers by the adaptive finite element method. Besides, the unstructured inverse mesh efficiently handles multiple scale structures and allows for fine-scale model parameters within the region of interest. Our mesh generation engine keeps track of the refinement hierarchy so that the map of conductivity and sensitivity kernel between the forward and inverse mesh is retained. We employ the adjoint-reciprocity method to calculate the sensitivity kernels which establish a linear relationship between changes in the conductivity model and changes in the modeled responses. Our code uses a direcy solver for the linear systems, so the adjoint problem is efficiently computed by re-using the factorization from the primary problem. Further computational efficiency and scalability is obtained in the regularized Gauss-Newton portion of the inversion using parallel dense matrix-matrix multiplication and matrix factorization routines implemented with the ScaLAPACK library. We show the scalability, reliability and the potential of the algorithm to deal with

Subspace-based Inverse Uncertainty Quantification for Nuclear Data Assessment

Energy Technology Data Exchange (ETDEWEB)

Khuwaileh, B.A., E-mail: bakhuwai@ncsu.edu; Abdel-Khalik, H.S.

2015-01-15

Safety analysis and design optimization depend on the accurate prediction of various reactor attributes. Predictions can be enhanced by reducing the uncertainty associated with the attributes of interest. An inverse problem can be defined and solved to assess the sources of uncertainty, and experimental effort can be subsequently directed to further improve the uncertainty associated with these sources. In this work a subspace-based algorithm for inverse sensitivity/uncertainty quantification (IS/UQ) has been developed to enable analysts account for all sources of nuclear data uncertainties in support of target accuracy assessment-type analysis. An approximate analytical solution of the optimization problem is used to guide the search for the dominant uncertainty subspace. By limiting the search to a subspace, the degrees of freedom available for the optimization search are significantly reduced. A quarter PWR fuel assembly is modeled and the accuracy of the multiplication factor and the fission reaction rate are used as reactor attributes whose uncertainties are to be reduced. Numerical experiments are used to demonstrate the computational efficiency of the proposed algorithm. Our ongoing work is focusing on extending the proposed algorithm to account for various forms of feedback, e.g., thermal-hydraulics and depletion effects.

Significant association of serum creatinine with HbA1C in impaired glucose tolerant Pakistani subjects.

Science.gov (United States)

Farasat, Tasnim; Sharif, Saima; Naz, Shagufta; Fazal, Sabiha

2015-01-01

The present study was conducted to assess the serum concentration of creatinine and determine its relationship with potential risk factors of diabetes in Impaired Glucose tolerance subjects. This cross sectional study was conducted on 100 IGT patients who attended Amin Hayat diabetic center in Lahore from January 2011- June 2011. Patients with age group 34-67 years, (both sexes) were included in the study. Different demographic parameters as age, BMI, WHR, B.P, personal history and socioeconomic status were recorded. Oral Glucose Tolerance Test was performed. The biochemical parameters including HbA1c, lipid profile, urea, uric acid, creatinine and bilirubin level were measured by chemistry analyzer. A strong correlation between creatinine and HbA1c was observed. The level of creatinine was also significantly associated with age in IGT subjects. Creatinine is non-significantly correlated with Cholesterol, LDL-Chol and TG while negatively significantly associated with BMI, fasting blood glucose and HDL-Chol. The present study concluded significant association of serum creatinine with HbA1c, BMI and HDL cholesterol.

Common non-synonymous SNPs associated with breast cancer susceptibility

DEFF Research Database (Denmark)

Milne, Roger L; Burwinkel, Barbara; Michailidou, Kyriaki

2014-01-01

Candidate variant association studies have been largely unsuccessful in identifying common breast cancer susceptibility variants, although most studies have been underpowered to detect associations of a realistic magnitude. We assessed 41 common non-synonymous single-nucleotide polymorphisms (ns......SNPs) for which evidence of association with breast cancer risk had been previously reported. Case-control data were combined from 38 studies of white European women (46 450 cases and 42 600 controls) and analyzed using unconditional logistic regression. Strong evidence of association was observed for three ns...... associations reached genome-wide statistical significance in a combined analysis of available data, including independent data from nine genome-wide association studies (GWASs): for ATXN7-K264R, OR = 1.07 (95% CI = 1.05-1.10, P = 1.0 × 10(-8)); for AKAP9-M463I, OR = 1.05 (95% CI = 1.04-1.07, P = 2.0 × 10...

3D inversion of full tensor magnetic gradiometry (FTMG) data

DEFF Research Database (Denmark)

Zhdanov, Michael; Cai, Hongzhu; Wilson, Glenn

2011-01-01

Following recent advances in SQUID technology, full tensor magnetic gradiometry (FTMG) is emerging as a practical exploration method. We introduce 3D regularized focusing inversion for FTMG data. Our model studies show that inversion of magnetic tensor data can significantly improve resolution...... compared to inversion of magnetic vector data for the same model. We present a case study for the 3D inversion of GETMAG® FTMG data acquired over a magnetite skarn at Tallawang, Australia. The results obtained from our 3D inversion agree very well with the known geology of the area....

Association between periodontal disease and non-communicable diseases

Science.gov (United States)

Lee, Jae-Hong; Oh, Jin-Young; Youk, Tae-Mi; Jeong, Seong-Nyum; Kim, Young-Taek; Choi, Seong-Ho

2017-01-01

Abstract The National Health Insurance Service–Health Examinee Cohort during 2002 to 2013 was used to investigate the associations between periodontal disease (PD) and the following non-communicable diseases (NCDs): hypertension, diabetes mellitus, osteoporosis, cerebral infarction, angina pectoris, myocardial infarction, and obesity. Univariate and multivariate logistic regression analyses adjusting for potential confounders during the follow-up period—including age, sex, household income, insurance status, residence area, health status, and comorbidities—were used to estimated odds ratios (ORs) with 95% confidence intervals (CIs) in order to assess the associations between PD and NCDs. We enrolled 200,026 patients with PD and 154,824 subjects with a healthy oral status. Statistically, significant associations were found between PD and the investigated NCDs except for cerebral and myocardial infarction after adjusting for sociodemographic and comorbidity factors (P periodontitis pathogenesis as a triggering and mediating mechanism. PMID:28658175

Association between bilirubin and risk of Non-Alcoholic Fatty Liver Disease based on a prospective cohort study.

Science.gov (United States)

Tian, Jianbo; Zhong, Rong; Liu, Cheng; Tang, Yuhan; Gong, Jing; Chang, Jiang; Lou, Jiao; Ke, Juntao; Li, Jiaoyuan; Zhang, Yi; Yang, Yang; Zhu, Ying; Gong, Yajie; Xu, Yanyan; Liu, Peiyi; Yu, Xiao; Xiao, Lin; Du, Min; Yang, Ling; Yuan, Jing; Wang, Youjie; Chen, Weihong; Wei, Sheng; Liang, Yuan; Zhang, Xiaomin; He, Meian; Wu, Tangchun; Yao, Ping; Miao, Xiaoping

2016-08-03

The study aimed to assess the association between total, direct, and indirect bilirubin and nonalcoholic fatty live disease (NAFLD) risk given its high prevalence and serious clinical prognosis. Among 27,009 subjects who participated in a healthy screening program from the Dongfeng-Tongji cohort study in 2008, 8189 eligible subjects (aged 35-86 years; males, 43.95%) were ultimately enrolled. The incidence rates of NAFLD in 2013 were compared with respect to baseline bilirubin levels among subjects free of NAFLD, and the effect sizes were estimated by logistic regression analysis. During 5 years follow-up, we observed 1956 cases of newly developed NAFLD with the overall incidence of 23.88%. Direct bilirubin was presented to inversely associate with NAFLD risk. Compared with quartile 1 of direct bilirubin, the multivariable-adjusted ORs (95% CIs) for NAFLD of quartile 2 to 4 were 1.104 (0.867-1.187), 0.843 (0.719-0.989), and 0.768 (0.652-0.905), respectively, P for trend 0.002). Similarly, inverse effects of direct bilirubin on NAFLD incidence were also observed when stratified by sex and BMI. However, no significant associations were found between total, and indirect bilirubin and NAFLD risk. Direct bilirubin reduced NAFLD risk independent of possible confounders among middle-aged and elderly Chinese population, probably based on the endogenous antioxidation of bilirubin.

Physiological Aldosterone Concentrations Are Associated with Alterations of Lipid Metabolism: Observations from the General Population.

Science.gov (United States)

Hannich, M; Wallaschofski, H; Nauck, M; Reincke, M; Adolf, C; Völzke, H; Rettig, R; Hannemann, A

2018-01-01

Aldosterone and high-density lipoprotein cholesterol (HDL-C) are involved in many pathophysiological processes that contribute to the development of cardiovascular diseases. Previously, associations between the concentrations of aldosterone and certain components of the lipid metabolism in the peripheral circulation were suggested, but data from the general population is sparse. We therefore aimed to assess the associations between aldosterone and HDL-C, low-density lipoprotein cholesterol (LDL-C), total cholesterol, triglycerides, or non-HDL-C in the general adult population. Data from 793 men and 938 women aged 25-85 years who participated in the first follow-up of the Study of Health in Pomerania were obtained. The associations of aldosterone with serum lipid concentrations were assessed in multivariable linear regression models adjusted for sex, age, body mass index (BMI), estimated glomerular filtration rate (eGFR), and HbA1c. The linear regression models showed statistically significant positive associations of aldosterone with LDL-C ( β -coefficient = 0.022, standard error = 0.010, p = 0.03) and non-HDL-C ( β -coefficient = 0.023, standard error = 0.009, p = 0.01) as well as an inverse association of aldosterone with HDL-C ( β -coefficient = -0.022, standard error = 0.011, p = 0.04). The present data show that plasma aldosterone is positively associated with LDL-C and non-HDL-C and inversely associated with HDL-C in the general population. Our data thus suggests that aldosterone concentrations within the physiological range may be related to alterations of lipid metabolism.

Point-source inversion techniques

Science.gov (United States)

Langston, Charles A.; Barker, Jeffrey S.; Pavlin, Gregory B.

1982-11-01

A variety of approaches for obtaining source parameters from waveform data using moment-tensor or dislocation point source models have been investigated and applied to long-period body and surface waves from several earthquakes. Generalized inversion techniques have been applied to data for long-period teleseismic body waves to obtain the orientation, time function and depth of the 1978 Thessaloniki, Greece, event, of the 1971 San Fernando event, and of several events associated with the 1963 induced seismicity sequence at Kariba, Africa. The generalized inversion technique and a systematic grid testing technique have also been used to place meaningful constraints on mechanisms determined from very sparse data sets; a single station with high-quality three-component waveform data is often sufficient to discriminate faulting type (e.g., strike-slip, etc.). Sparse data sets for several recent California earthquakes, for a small regional event associated with the Koyna, India, reservoir, and for several events at the Kariba reservoir have been investigated in this way. Although linearized inversion techniques using the moment-tensor model are often robust, even for sparse data sets, there are instances where the simplifying assumption of a single point source is inadequate to model the data successfully. Numerical experiments utilizing synthetic data and actual data for the 1971 San Fernando earthquake graphically demonstrate that severe problems may be encountered if source finiteness effects are ignored. These techniques are generally applicable to on-line processing of high-quality digital data, but source complexity and inadequacy of the assumed Green's functions are major problems which are yet to be fully addressed.

High performance matrix inversion based on LU factorization for multicore architectures

KAUST Repository

Dongarra, Jack

2011-01-01

The goal of this paper is to present an efficient implementation of an explicit matrix inversion of general square matrices on multicore computer architecture. The inversion procedure is split into four steps: 1) computing the LU factorization, 2) inverting the upper triangular U factor, 3) solving a linear system, whose solution yields inverse of the original matrix and 4) applying backward column pivoting on the inverted matrix. Using a tile data layout, which represents the matrix in the system memory with an optimized cache-aware format, the computation of the four steps is decomposed into computational tasks. A directed acyclic graph is generated on the fly which represents the program data flow. Its nodes represent tasks and edges the data dependencies between them. Previous implementations of matrix inversions, available in the state-of-the-art numerical libraries, are suffer from unnecessary synchronization points, which are non-existent in our implementation in order to fully exploit the parallelism of the underlying hardware. Our algorithmic approach allows to remove these bottlenecks and to execute the tasks with loose synchronization. A runtime environment system called QUARK is necessary to dynamically schedule our numerical kernels on the available processing units. The reported results from our LU-based matrix inversion implementation significantly outperform the state-of-the-art numerical libraries such as LAPACK (5x), MKL (5x) and ScaLAPACK (2.5x) on a contemporary AMD platform with four sockets and the total of 48 cores for a matrix of size 24000. A power consumption analysis shows that our high performance implementation is also energy efficient and substantially consumes less power than its competitors. © 2011 ACM.

Factors associated with urban non-fatal road-accident severity.

Science.gov (United States)

Potoglou, Dimitris; Carlucci, Fabio; Cirà, Andrea; Restaino, Marialuisa

2018-02-05

This paper reports on the factors associated with non-fatal urban-road accident severity. Data on accidents were gathered from the local traffic police in the City of Palermo, one of the six most populated cities in Italy. Findings from a mixed-effects logistic-regression model suggest that accident severity increases when two young drivers are involved, road traffic conditions are light/normal and when vehicles crash on a two-way road or carriageway. Speeding is more likely to cause slight or serious injury even when compared to a vehicle moving towards the opposite direction of traffic. An accident during the summer is more likely to result in a slight or serious injury than an accident during the winter, which is in line with evidence from Southern Europe and the Middle East. Finally, the severity of non-fatal accident injuries in an urban area of Southern Europe was significantly associated with speeding, the age of the driver and seasonality.

Inverse scattering scheme for the Dirac equation at fixed energy

International Nuclear Information System (INIS)

Leeb, H.; Lehninger, H.; Schilder, C.

2001-01-01

Full text: Based on the concept of generalized transformation operators a new hierarchy of Dirac equations with spherical symmetric scalar and fourth component vector potentials is presented. Within this hierarchy closed form expressions for the solutions, the potentials and the S-matrix can be given in terms of solutions of the original Dirac equation. Using these transformations an inverse scattering scheme has been constructed for the Dirac equation which is the analog to the rational scheme in the non-relativistic case. The given method provides for the first time an inversion scheme with closed form expressions for the S-matrix for non-relativistic scattering problems with central and spin-orbit potentials. (author)

Skeletal muscle fat content is inversely associated with bone strength in young girls.

Science.gov (United States)

Farr, Joshua N; Funk, Janet L; Chen, Zhao; Lisse, Jeffrey R; Blew, Robert M; Lee, Vinson R; Laudermilk, Monica; Lohman, Timothy G; Going, Scott B

2011-09-01

Childhood obesity is an established risk factor for metabolic disease. The influence of obesity on bone development, however, remains controversial and may depend on the pattern of regional fat deposition. Therefore, we examined the associations of regional fat compartments of the calf and thigh with weight-bearing bone parameters in girls. Data from 444 girls aged 9 to 12 years from the Jump-In: Building Better Bones study were analyzed. Peripheral quantitative computed tomography (pQCT) was used to assess bone parameters at metaphyseal and diaphyseal sites of the femur and tibia along with subcutaneous adipose tissue (SAT, mm(2) ) and muscle density (mg/cm(3) ), an index of skeletal muscle fat content. As expected, SAT was positively correlated with total-body fat mass (r = 0.87-0.89, p  .05), except the distal tibia (β = 0.09, p = .03). In conclusion, skeletal muscle fat content of the calf and thigh is inversely associated with weight-bearing bone strength in young girls. Copyright © 2011 American Society for Bone and Mineral Research.

Linearized versus non-linear inverse methods for seismic localization of underground sources

DEFF Research Database (Denmark)

Oh, Geok Lian; Jacobsen, Finn

2013-01-01

The problem of localization of underground sources from seismic measurements detected by several geophones located on the ground surface is addressed. Two main approaches to the solution of the problem are considered: a beamforming approach that is derived from the linearized inversion problem, a...

The association between sex hormone-binding globulin and type 2 diabetes in Nigerian men

Directory of Open Access Journals (Sweden)

Fayefori M. Abbiyesuku

2013-07-01

Full Text Available Background: Epidemiological studies have shown that sex hormone-binding globulin (SHBG has a role in glucose homeostasis in both men and women. However, a prospective study on Japanese-American subjects concluded that SHBG was not a significant risk factor in either men or women, suggesting ethnic differences. We were not aware of any evaluation of SHBG in subjects of African ancestry. Objectives: We investigated the association between SHBG and insulin resistance in type 2 diabetic diabetic men in a hospital in Nigeria. Method: Forty-eight male subjects with type 2 diabetes and 20 non-diabetic male subjects were recruited in this cross-sectional hospital-based study by the convenient sampling method.Height and circumferences around the waist and hip were measured to the nearest 0.5 cm and the waist–hip ratio was calculated from this measurement. Weight was measured and body mass index was calculated. Fasting plasma glucose concentration was measured by the glucose oxidase method with a between-run coefficient of variation of 3%. Insulin and SHBG were measured by means of enzyme-linked immunosorbent assay (ELISA. Results: There was a statistically-significant difference between test results for the diabetic and non-diabetic patients. The mean SHBG concentration was higher in the non-diabetic group (42.2 nmol/L than the diabetic group (30.5 nmol/L. A significant inverse association between insulin resistance and SHBG was observed (r = 0.353, p < 0.015. Conclusion: This study supported earlier observations that a significant inverse correlation exists between SHBG and insulin resistance and provides evidence that the relationship may extend to type 2 diabetic men of African ancestry in Nigeria.

How significant is the ‘significant other’? Associations between significant others’ health behaviors and attitudes and young adults’ health outcomes

Directory of Open Access Journals (Sweden)

Berge Jerica M

2012-04-01

Full Text Available Abstract Background Having a significant other has been shown to be protective against physical and psychological health conditions for adults. Less is known about the period of emerging young adulthood and associations between significant others’ weight and weight-related health behaviors (e.g. healthy dietary intake, the frequency of physical activity, weight status. This study examined the association between significant others’ health attitudes and behaviors regarding eating and physical activity and young adults’ weight status, dietary intake, and physical activity. Methods This study uses data from Project EAT-III, a population-based cohort study with emerging young adults from diverse ethnic and socioeconomic backgrounds (n = 1212. Logistic regression models examining cross-sectional associations, adjusted for sociodemographics and health behaviors five years earlier, were used to estimate predicted probabilities and calculate prevalence differences. Results Young adult women whose significant others had health promoting attitudes/behaviors were significantly less likely to be overweight/obese and were more likely to eat ≥ 5 fruits/vegetables per day and engage in ≥ 3.5 hours/week of physical activity, compared to women whose significant others did not have health promoting behaviors/attitudes. Young adult men whose significant other had health promoting behaviors/attitudes were more likely to engage in ≥ 3.5 hours/week of physical activity compared to men whose significant others did not have health promoting behaviors/attitudes. Conclusions Findings suggest the protective nature of the significant other with regard to weight-related health behaviors of young adults, particularly for young adult women. Obesity prevention efforts should consider the importance of including the significant other in intervention efforts with young adult women and potentially men.

Chromosomal inversions effect body size and shape in different breeding resources in Drosophila buzzatii.

Science.gov (United States)

Fernández Iriarte, P J; Norry, F M; Hasson, E R

2003-07-01

The cactophilic Drosophila buzzatii provides an excellent model for the study of reaction norms across discrete environments because it breeds on rotting tissues (rots) of very different cactus species. Here we test the possible effects of second chromosome inversions on body size and shape (wing loading) across suitable natural breeding substrates. Using homokaryotypic stocks derived from several lines homozygous for four naturally occurring chromosomal inversions, we show that arrangements significantly affect size-related traits and wing loading. In addition, karyotypes show differing effects, across natural breeding resources, for wing loading. The 2st and 2jz(3) arrangements decrease and the 2j arrangement increases wing loading. For thorax length and wing loading, karyotypic correlations across host plants are slightly lower in females than in males. These results support the hypothesis that these traits have a genetic basis associated with the inversion polymorphism.

Bayesian inversion of refraction seismic traveltime data

Science.gov (United States)

Ryberg, T.; Haberland, Ch

2018-03-01

We apply a Bayesian Markov chain Monte Carlo (McMC) formalism to the inversion of refraction seismic, traveltime data sets to derive 2-D velocity models below linear arrays (i.e. profiles) of sources and seismic receivers. Typical refraction data sets, especially when using the far-offset observations, are known as having experimental geometries which are very poor, highly ill-posed and far from being ideal. As a consequence, the structural resolution quickly degrades with depth. Conventional inversion techniques, based on regularization, potentially suffer from the choice of appropriate inversion parameters (i.e. number and distribution of cells, starting velocity models, damping and smoothing constraints, data noise level, etc.) and only local model space exploration. McMC techniques are used for exhaustive sampling of the model space without the need of prior knowledge (or assumptions) of inversion parameters, resulting in a large number of models fitting the observations. Statistical analysis of these models allows to derive an average (reference) solution and its standard deviation, thus providing uncertainty estimates of the inversion result. The highly non-linear character of the inversion problem, mainly caused by the experiment geometry, does not allow to derive a reference solution and error map by a simply averaging procedure. We present a modified averaging technique, which excludes parts of the prior distribution in the posterior values due to poor ray coverage, thus providing reliable estimates of inversion model properties even in those parts of the models. The model is discretized by a set of Voronoi polygons (with constant slowness cells) or a triangulated mesh (with interpolation within the triangles). Forward traveltime calculations are performed by a fast, finite-difference-based eikonal solver. The method is applied to a data set from a refraction seismic survey from Northern Namibia and compared to conventional tomography. An inversion test

Study of temperature inversion symmetry for the twisted Wess-Zumino model

International Nuclear Information System (INIS)

Oikonomou, V K

2007-01-01

The temperature inversion symmetry, for a non-interacting supersymmetric ensemble, at finite volume, is studied. It is found that the scaled free energy, f(ξ), is antisymmetric under temperature inversion transformation, i.e. f(ξ) = -ξ d (1/ξ). This occurs for antiperiodic bosons and periodic fermions in the compact dimension. In contrast, for periodic bosons and antiperiodic fermions, f(ξ = ξ d (1/ξ)

Inversions

Science.gov (United States)

Brown, Malcolm

2009-01-01

Inversions are fascinating phenomena. They are reversals of the normal or expected order. They occur across a wide variety of contexts. What do inversions have to do with learning spaces? The author suggests that they are a useful metaphor for the process that is unfolding in higher education with respect to education. On the basis of…

Tutorial for Wave Equation Inversion of Skeletonized Data

KAUST Repository

Lu, Kai

2017-04-25

Full waveform inversion of seismic data is often plagued by cycle skipping problems so that an iterative optimization method often gets stuck in a local minimum. To avoid this problem we simplify the objective function so that the iterative solution can quickly converge to a solution in the vicinity of the global minimum. The objective function is simplified by only using parsimonious and important portions of the data, which are defined as skeletonized data. We now present a mostly non-mathematical tutorial that explains the theory of skeletonized inversion. We also show its effectiveness with examples.

Solving probabilistic inverse problems rapidly with prior samples

NARCIS (Netherlands)

Käufl, Paul; Valentine, Andrew P.; de Wit, Ralph W.; Trampert, Jeannot

2016-01-01

Owing to the increasing availability of computational resources, in recent years the probabilistic solution of non-linear, geophysical inverse problems by means of sampling methods has become increasingly feasible. Nevertheless, we still face situations in which a Monte Carlo approach is not

Dustfall Effect on Hyperspectral Inversion of Chlorophyll Content - a Laboratory Experiment

Science.gov (United States)

Chen, Yuteng; Ma, Baodong; Li, Xuexin; Zhang, Song; Wu, Lixin

2018-04-01

Dust pollution is serious in many areas of China. It is of great significance to estimate chlorophyll content of vegetation accurately by hyperspectral remote sensing for assessing the vegetation growth status and monitoring the ecological environment in dusty areas. By using selected vegetation indices including Medium Resolution Imaging Spectrometer Terrestrial Chlorophyll Index (MTCI) Double Difference Index (DD) and Red Edge Position Index (REP), chlorophyll inversion models were built to study the accuracy of hyperspectral inversion of chlorophyll content based on a laboratory experiment. The results show that: (1) REP exponential model has the most stable accuracy for inversion of chlorophyll content in dusty environment. When dustfall amount is less than 80 g/m2, the inversion accuracy based on REP is stable with the variation of dustfall amount. When dustfall amount is greater than 80 g/m2, the inversion accuracy is slightly fluctuation. (2) Inversion accuracy of DD is worst among three models. (3) MTCI logarithm model has high inversion accuracy when dustfall amount is less than 80 g/m2; When dustfall amount is greater than 80 g/m2, inversion accuracy decreases regularly and inversion accuracy of modified MTCI (mMTCI) increases significantly. The results provide experimental basis and theoretical reference for hyperspectral remote sensing inversion of chlorophyll content.

Frequency of soup intake and amount of dietary fiber intake are inversely associated with plasma leptin concentrations in Japanese adults.

Science.gov (United States)

Kuroda, Motonaka; Ohta, Masanori; Okufuji, Tatsuya; Takigami, Chieko; Eguchi, Masafumi; Hayabuchi, Hitomi; Ikeda, Masaharu

2010-06-01

Previous studies have shown that the intake of soup negatively correlates with the body mass index (BMI), suggesting that soup intake reduces the risk of obesity. In this study, to clarify the association of the intake of soup and various nutrients with plasma leptin concentration, a cross-sectional study on 504 Japanese adults aged 20-76 years (103 men and 401 women) was performed. The intake of soup and various nutrients was investigated by food frequency questionnaires. Plasma leptin concentration was measured in fasting blood by radioimmunoassay. The correlation was analyzed by multiple regression analysis. The average frequency of soup intake was 7.6 times/week. The average plasma leptin concentration was 7.76 ng/ml. After adjusting the confounding factors, the frequency of soup intake has a significant inverse association with plasma leptin concentration. Among the macronutrients, only dietary fiber intake negatively correlated with plasma leptin concentration after the adjustment for potential confounding factors. These results suggest that the intakes of soup and dietary fiber were negatively correlated with plasma leptin concentration in Japanese adults. Copyright 2010 Elsevier Ltd. All rights reserved.

Inversion of lithium heparin gel tubes after centrifugation is a significant source of bias in clinical chemistry testing.

Science.gov (United States)

Lippi, Giuseppe; Salvagno, Gian Luca; Danese, Elisa; Lima-Oliveira, Gabriel; Brocco, Giorgio; Guidi, Gian Cesare

2014-09-25

This study was planned to establish whether random orientation of gel tubes after centrifugation may impair sample quality. Eight gel tubes were collected from 17 volunteers: 2 Becton Dickinson (BD) serum tubes, 2 Terumo serum tubes, 2 BD lithium heparin tubes and 2 Terumo lithium heparin tubes. One patient's tube for each category was kept in a vertical, closure-up position for 90 min ("upright"), whereas paired tubes underwent bottom-up inversion every 15 min, for 90 min ("inverted"). Immediately after this period of time, 14 clinical chemistry analytes, serum indices and complete blood count were then assessed in all tubes. Significant increases were found for phosphate and lipaemic index in all inverted tubes, along with AST, calcium, cholesterol, LDH, potassium, hemolysis index, leukocytes, erythrocytes and platelets limited to lithium heparin tubes. The desirable quality specifications were exceeded for AST, LDH, and potassium in inverted lithium heparin tubes. Residual leukocytes, erythrocytes, platelets and cellular debris were also significantly increased in inverted lithium heparin tubes. Lithium heparin gel tubes should be maintained in a vertical, closure-up position after centrifugation. Copyright © 2014 Elsevier B.V. All rights reserved.

Seismic velocity structure of the forearc in northern Cascadia from Bayesian inversion of teleseismic data

Science.gov (United States)

Gosselin, J.; Audet, P.; Schaeffer, A. J.

2017-12-01

The seismic velocity structure in the forearc of subduction zones provides important constraints on material properties, with implications for seismogenesis. In Cascadia, previous studies have imaged a downgoing low-velocity zone (LVZ) characterized by an elevated P-to-S velocity ratio (Vp/Vs) down to 45 km depth, near the intersection with the mantle wedge corner, beyond which the signature of the LVZ disappears. These results, combined with the absence of a "normal" continental Moho, indicate that the down-going oceanic crust likely carries large amounts of overpressured free fluids that are released downdip at the onset of crustal eclogitization, and are further stored in the mantle wedge as serpentinite. These overpressured free fluids affect the stability of the plate interface and facilitate slow slip. These results are based on the inversion and migration of scattered teleseismic data for individual layer properties; a methodology which suffers from regularization and smoothing, non-uniqueness, and does not consider model uncertainty. This study instead applies trans-dimensional Bayesian inversion of teleseismic data collected in the forearc of northern Cascadia (the CAFÉ experiment in northern Washington) to provide rigorous, quantitative estimates of local velocity structure, and associated uncertainties (particularly Vp/Vs structure and depth to the plate interface). Trans-dimensional inversion is a generalization of fixed-dimensional inversion that includes the number (and type) of parameters required to describe the velocity model (or data error model) as unknown in the problem. This allows model complexity to be inherently determined by data information content, not by subjective regularization. The inversion is implemented here using the reversible-jump Markov chain Monte Carlo algorithm. The result is an ensemble set of candidate velocity-structure models which approximate the posterior probability density (PPD) of the model parameters. The solution

Inverse semigroups the theory of partial symmetries

CERN Document Server

Lawson, Mark V

1998-01-01

Symmetry is one of the most important organising principles in the natural sciences. The mathematical theory of symmetry has long been associated with group theory, but it is a basic premise of this book that there are aspects of symmetry which are more faithfully represented by a generalization of groups called inverse semigroups. The theory of inverse semigroups is described from its origins in the foundations of differential geometry through to its most recent applications in combinatorial group theory, and the theory tilings.

Androgen Receptor Expression in Early Triple-Negative Breast Cancer: Clinical Significance and Prognostic Associations

Energy Technology Data Exchange (ETDEWEB)

Pistelli, Mirco, E-mail: mirco.pistelli@alice.it; Caramanti, Miriam [Clinica di Oncologia Medica, AO Ospedali Riuniti-Ancona, Università Politecnica delle Marche, Ancona 60020 (Italy); Biscotti, Tommasina; Santinelli, Alfredo [Anatomia Patologica, AO Ospedali Riuniti-Ancona, Università Politecnica delle Marche, Ancona 60020 (Italy); Pagliacci, Alessandra; De Lisa, Mariagrazia; Ballatore, Zelmira; Ridolfi, Francesca; Maccaroni, Elena; Bracci, Raffaella; Berardi, Rossana; Battelli, Nicola; Cascinu, Stefano [Clinica di Oncologia Medica, AO Ospedali Riuniti-Ancona, Università Politecnica delle Marche, Ancona 60020 (Italy)

2014-06-27

Background: Triple-negative breast cancers (TNBC) are characterized by aggressive tumour biology resulting in a poor prognosis. Androgen receptor (AR) is one of newly emerging biomarker in TNBC. In recent years, ARs have been demonstrated to play an important role in the genesis and in the development of breast cancer, although their prognostic role is still debated. In the present study, we explored the correlation of AR expression with clinical, pathological and molecular features and its impact on prognosis in early TNBC. Patients and Methods: ARs were considered positive in case of tumors with >10% nuclear-stained. Survival distribution was estimated by the Kaplan Meier method. The univariate and multivariate analyses were performed. The difference among variables were calculated by chi-square test. Results: 81 TNBC patients diagnosed between January 2006 and December 2011 were included in the analysis. Slides were stained immunohistochemically for estrogen and progesterone receptors, HER-2, Ki-67, ALDH1, e-cadherin and AR. Of the 81 TNBC samples, 18.8% showed positive immunostaining for AR, 23.5% and 44.4% of patients were negative for e-cadherin and ALDH1, respectively. Positive AR immunostaining was inversely correlated with a higher Ki-67 (p < 0.0001) and a lympho-vascular invasion (p = 0.01), but no other variables. Univariate survival analysis revealed that AR expression was not associated with disease-free survival (p = 0.72) or overall survival (p = 0.93). Conclusions: The expression of AR is associated with some biological features of TNBC, such as Ki-67 and lympho-vascular invasion; nevertheless the prognostic significance of AR was not documented in our analysis. However, since ARs are expressed in a significant number of TNBC, prospective studies in order to determine the biological mechanisms and their potential role as novel treatment target.

Androgen Receptor Expression in Early Triple-Negative Breast Cancer: Clinical Significance and Prognostic Associations

Directory of Open Access Journals (Sweden)

Mirco Pistelli

2014-06-01

Full Text Available Background: Triple-negative breast cancers (TNBC are characterized by aggressive tumour biology resulting in a poor prognosis. Androgen receptor (AR is one of newly emerging biomarker in TNBC. In recent years, ARs have been demonstrated to play an important role in the genesis and in the development of breast cancer, although their prognostic role is still debated. In the present study, we explored the correlation of AR expression with clinical, pathological and molecular features and its impact on prognosis in early TNBC. Patients and Methods: ARs were considered positive in case of tumors with >10% nuclear-stained. Survival distribution was estimated by the Kaplan Meier method. The univariate and multivariate analyses were performed. The difference among variables were calculated by chi-square test. Results: 81 TNBC patients diagnosed between January 2006 and December 2011 were included in the analysis. Slides were stained immunohistochemically for estrogen and progesterone receptors, HER-2, Ki-67, ALDH1, e-cadherin and AR. Of the 81 TNBC samples, 18.8% showed positive immunostaining for AR, 23.5% and 44.4% of patients were negative for e-cadherin and ALDH1, respectively. Positive AR immunostaining was inversely correlated with a higher Ki-67 (p < 0.0001 and a lympho-vascular invasion (p = 0.01, but no other variables. Univariate survival analysis revealed that AR expression was not associated with disease-free survival (p = 0.72 or overall survival (p = 0.93. Conclusions: The expression of AR is associated with some biological features of TNBC, such as Ki-67 and lympho-vascular invasion; nevertheless the prognostic significance of AR was not documented in our analysis. However, since ARs are expressed in a significant number of TNBC, prospective studies in order to determine the biological mechanisms and their potential role as novel treatment target.

Androgen Receptor Expression in Early Triple-Negative Breast Cancer: Clinical Significance and Prognostic Associations

International Nuclear Information System (INIS)

Pistelli, Mirco; Caramanti, Miriam; Biscotti, Tommasina; Santinelli, Alfredo; Pagliacci, Alessandra; De Lisa, Mariagrazia; Ballatore, Zelmira; Ridolfi, Francesca; Maccaroni, Elena; Bracci, Raffaella; Berardi, Rossana; Battelli, Nicola; Cascinu, Stefano

2014-01-01

Background: Triple-negative breast cancers (TNBC) are characterized by aggressive tumour biology resulting in a poor prognosis. Androgen receptor (AR) is one of newly emerging biomarker in TNBC. In recent years, ARs have been demonstrated to play an important role in the genesis and in the development of breast cancer, although their prognostic role is still debated. In the present study, we explored the correlation of AR expression with clinical, pathological and molecular features and its impact on prognosis in early TNBC. Patients and Methods: ARs were considered positive in case of tumors with >10% nuclear-stained. Survival distribution was estimated by the Kaplan Meier method. The univariate and multivariate analyses were performed. The difference among variables were calculated by chi-square test. Results: 81 TNBC patients diagnosed between January 2006 and December 2011 were included in the analysis. Slides were stained immunohistochemically for estrogen and progesterone receptors, HER-2, Ki-67, ALDH1, e-cadherin and AR. Of the 81 TNBC samples, 18.8% showed positive immunostaining for AR, 23.5% and 44.4% of patients were negative for e-cadherin and ALDH1, respectively. Positive AR immunostaining was inversely correlated with a higher Ki-67 (p < 0.0001) and a lympho-vascular invasion (p = 0.01), but no other variables. Univariate survival analysis revealed that AR expression was not associated with disease-free survival (p = 0.72) or overall survival (p = 0.93). Conclusions: The expression of AR is associated with some biological features of TNBC, such as Ki-67 and lympho-vascular invasion; nevertheless the prognostic significance of AR was not documented in our analysis. However, since ARs are expressed in a significant number of TNBC, prospective studies in order to determine the biological mechanisms and their potential role as novel treatment target

Inverse Problems in a Bayesian Setting

KAUST Repository

Matthies, Hermann G.

2016-02-13

In a Bayesian setting, inverse problems and uncertainty quantification (UQ)—the propagation of uncertainty through a computational (forward) model—are strongly connected. In the form of conditional expectation the Bayesian update becomes computationally attractive. We give a detailed account of this approach via conditional approximation, various approximations, and the construction of filters. Together with a functional or spectral approach for the forward UQ there is no need for time-consuming and slowly convergent Monte Carlo sampling. The developed sampling-free non-linear Bayesian update in form of a filter is derived from the variational problem associated with conditional expectation. This formulation in general calls for further discretisation to make the computation possible, and we choose a polynomial approximation. After giving details on the actual computation in the framework of functional or spectral approximations, we demonstrate the workings of the algorithm on a number of examples of increasing complexity. At last, we compare the linear and nonlinear Bayesian update in form of a filter on some examples.

Inverse Problems in a Bayesian Setting

KAUST Repository

Matthies, Hermann G.; Zander, Elmar; Rosić, Bojana V.; Litvinenko, Alexander; Pajonk, Oliver

2016-01-01

In a Bayesian setting, inverse problems and uncertainty quantification (UQ)—the propagation of uncertainty through a computational (forward) model—are strongly connected. In the form of conditional expectation the Bayesian update becomes computationally attractive. We give a detailed account of this approach via conditional approximation, various approximations, and the construction of filters. Together with a functional or spectral approach for the forward UQ there is no need for time-consuming and slowly convergent Monte Carlo sampling. The developed sampling-free non-linear Bayesian update in form of a filter is derived from the variational problem associated with conditional expectation. This formulation in general calls for further discretisation to make the computation possible, and we choose a polynomial approximation. After giving details on the actual computation in the framework of functional or spectral approximations, we demonstrate the workings of the algorithm on a number of examples of increasing complexity. At last, we compare the linear and nonlinear Bayesian update in form of a filter on some examples.

Inverse source problems for eddy current equations

International Nuclear Information System (INIS)

Rodríguez, Ana Alonso; Valli, Alberto; Camaño, Jessika

2012-01-01

We study the inverse source problem for the eddy current approximation of Maxwell equations. As for the full system of Maxwell equations, we show that a volume current source cannot be uniquely identified by knowledge of the tangential components of the electromagnetic fields on the boundary, and we characterize the space of non-radiating sources. On the other hand, we prove that the inverse source problem has a unique solution if the source is supported on the boundary of a subdomain or if it is the sum of a finite number of dipoles. We address the applicability of this result for the localization of brain activity from electroencephalography and magnetoencephalography measurements. (paper)

Application of optical deformation analysis system on wedge splitting test and its inverse analysis

DEFF Research Database (Denmark)

Skocek, Jan; Stang, Henrik

2010-01-01

. Results of the inverse analysis are compared with traditional inverse analysis based on clip gauge data. Then the optically measured crack profile and crack tip position are compared with predictions done by the non-linear hinge model and a finite element analysis. It is shown that the inverse analysis...... based on the optically measured data can provide material parameters of the fictitious crack model matching favorably those obtained by classical inverse analysis based on the clip gauge data. Further advantages of using of the optical deformation analysis lie in identification of such effects...

Prognostic significance of CD95, P53, and BCL2 expression in extranodal non-Hodgkin's lymphoma

OpenAIRE

Chatzitolios , Anastasios; Venizelos , Ioannis; Tripsiannis , Gregory; Anastassopoulos , George; Papadopoulos , Nikolaos

2010-01-01

Abstract Apoptosis-related proteins play an important role in lymphoma cell death during chemotherapy. In our study, we investigated the prognostic significance of CD95, BCL2, and P53 expression in extranodal non-Hodgkin?s lymphoma (NHL). We examined 71 patients with extranodal NHL [45 diffuse large B-cell lymphomas (DLBCLs) and 26 mucosa-associated lymphoid tissue lymphomas (MALTLs)], 35 male and 36 female, with a median age of 65.8 years. The most common site of origin was the st...

Inverse Problems and Uncertainty Quantification

KAUST Repository

Litvinenko, Alexander

2014-01-06

In a Bayesian setting, inverse problems and uncertainty quantification (UQ) - the propagation of uncertainty through a computational (forward) modelare strongly connected. In the form of conditional expectation the Bayesian update becomes computationally attractive. This is especially the case as together with a functional or spectral approach for the forward UQ there is no need for time- consuming and slowly convergent Monte Carlo sampling. The developed sampling- free non-linear Bayesian update is derived from the variational problem associated with conditional expectation. This formulation in general calls for further discretisa- tion to make the computation possible, and we choose a polynomial approximation. After giving details on the actual computation in the framework of functional or spectral approximations, we demonstrate the workings of the algorithm on a number of examples of increasing complexity. At last, we compare the linear and quadratic Bayesian update on the small but taxing example of the chaotic Lorenz 84 model, where we experiment with the influence of different observation or measurement operators on the update.

Inverse Problems and Uncertainty Quantification

KAUST Repository

Litvinenko, Alexander; Matthies, Hermann G.

2014-01-01

In a Bayesian setting, inverse problems and uncertainty quantification (UQ) - the propagation of uncertainty through a computational (forward) modelare strongly connected. In the form of conditional expectation the Bayesian update becomes computationally attractive. This is especially the case as together with a functional or spectral approach for the forward UQ there is no need for time- consuming and slowly convergent Monte Carlo sampling. The developed sampling- free non-linear Bayesian update is derived from the variational problem associated with conditional expectation. This formulation in general calls for further discretisa- tion to make the computation possible, and we choose a polynomial approximation. After giving details on the actual computation in the framework of functional or spectral approximations, we demonstrate the workings of the algorithm on a number of examples of increasing complexity. At last, we compare the linear and quadratic Bayesian update on the small but taxing example of the chaotic Lorenz 84 model, where we experiment with the influence of different observation or measurement operators on the update.

Inverse problems and uncertainty quantification

KAUST Repository

Litvinenko, Alexander

2013-12-18

In a Bayesian setting, inverse problems and uncertainty quantification (UQ)— the propagation of uncertainty through a computational (forward) model—are strongly connected. In the form of conditional expectation the Bayesian update becomes computationally attractive. This is especially the case as together with a functional or spectral approach for the forward UQ there is no need for time- consuming and slowly convergent Monte Carlo sampling. The developed sampling- free non-linear Bayesian update is derived from the variational problem associated with conditional expectation. This formulation in general calls for further discretisa- tion to make the computation possible, and we choose a polynomial approximation. After giving details on the actual computation in the framework of functional or spectral approximations, we demonstrate the workings of the algorithm on a number of examples of increasing complexity. At last, we compare the linear and quadratic Bayesian update on the small but taxing example of the chaotic Lorenz 84 model, where we experiment with the influence of different observation or measurement operators on the update.

New RADIOM algorithm using inverse EOS

Science.gov (United States)

Busquet, Michel; Sokolov, Igor; Klapisch, Marcel

2012-10-01

The RADIOM model, [1-2], allows one to implement non-LTE atomic physics with a very low extra CPU cost. Although originally heuristic, RADIOM has been physically justified [3] and some accounting for auto-ionization has been included [2]. RADIOM defines an ionization temperature Tz derived from electronic density and actual electronic temperature Te. LTE databases are then queried for properties at Tz and NLTE values are derived from them. Some hydro-codes (like FAST at NRL, Ramis' MULTI, or the CRASH code at U.Mich) use inverse EOS starting from the total internal energy Etot and returning the temperature. In the NLTE case, inverse EOS requires to solve implicit relations between Te, Tz, and Etot. We shall describe these relations and an efficient solver successively implemented in some of our codes. [4pt] [1] M. Busquet, Radiation dependent ionization model for laser-created plasmas, Ph. Fluids B 5, 4191 (1993).[0pt] [2] M. Busquet, D. Colombant, M. Klapisch, D. Fyfe, J. Gardner. Improvements to the RADIOM non-LTE model, HEDP 5, 270 (2009).[0pt] [3] M.Busquet, Onset of pseudo-thermal equilibrium within configurations and super-configurations, JQSRT 99, 131 (2006)

Prognostic significance of MCM2, Ki-67 and gelsolin in non-small cell lung cancer

International Nuclear Information System (INIS)

Yang, Jun; Tan, Dongfeng; Ramnath, Nithya; Moysich, Kirsten B; Asch, Harold L; Swede, Helen; Alrawi, Sadir J; Huberman, Joel; Geradts, Joseph; Brooks, John SJ

2006-01-01

Uncontrolled proliferation and increased motility are hallmarks of neoplastic cells, therefore markers of proliferation and motility may be valuable in assessing tumor progression and prognosis. MCM2 is a member of the minichromosome maintenance (MCM) protein family. It plays critical roles in the initiation of DNA replication and in replication fork movement, and is intimately related to cell proliferation. Ki-67 is a proliferation antigen that is expressed during all but G 0 phases of the cell cycle. Gelsolin is an actin-binding protein that regulates the integrity of the actin cytoskeletal structure and facilitates cell motility. In this study, we assessed the prognostic significance of MCM2 and Ki-67, two markers of proliferation, and gelsolin, a marker of motility, in non-small cell lung cancer (NSCLC). 128 patients with pathologically confirmed, resectable NSCLC (stage I-IIIA) were included. Immunohistochemistry was utilized to measure the expressions of these markers in formalin-fixed, paraffin-embedded tumor tissues. Staining and scoring of MCM2, Ki-67 and gelsolin was independently performed. Analyses were performed to evaluate the prognostic significance of single expression of each marker, as well as the prognostic significance of composite expressions of MCM2 and gelsolin. Cox regression and Kaplan-Meier survival analysis were used for statistical analysis. Of the three markers, higher levels of gelsolin were significantly associated with an increased risk of death (adjusted RR = 1.89, 95% CI = 1.17–3.05, p = 0.01), and higher levels of MCM2 were associated with a non-significant increased risk of death (adjusted RR = 1.36, 95% CI = 0.84–2.20, p = 0.22). Combined, adjusted analyses revealed a significantly poor prognostic effect for higher expression of MCM2 and gelsolin compared to low expression of both biomarkers (RR = 2.32, 95% CI = 1.21–4.45, p = 0.01). Ki-67 did not display apparent prognostic effect in this study sample. The results suggest

Polymorphisms in the TLR4 and TLR5 gene are significantly associated with inflammatory bowel disease in German shepherd dogs.

Science.gov (United States)

Kathrani, Aarti; House, Arthur; Catchpole, Brian; Murphy, Angela; German, Alex; Werling, Dirk; Allenspach, Karin

2010-12-23

Inflammatory bowel disease (IBD) is considered to be the most common cause of vomiting and diarrhoea in dogs, and the German shepherd dog (GSD) is particularly susceptible. The exact aetiology of IBD is unknown, however associations have been identified between specific single-nucleotide polymorphisms (SNPs) in Toll-like receptors (TLRs) and human IBD. However, to date, no genetic studies have been undertaken in canine IBD. The aim of this study was to investigate whether polymorphisms in canine TLR 2, 4 and 5 genes are associated with IBD in GSDs. Mutational analysis of TLR2, TLR4 and TLR5 was performed in 10 unrelated GSDs with IBD. Four non-synonymous SNPs (T23C, G1039A, A1571T and G1807A) were identified in the TLR4 gene, and three non-synonymous SNPs (G22A, C100T and T1844C) were identified in the TLR5 gene. The non-synonymous SNPs identified in TLR4 and TLR5 were evaluated further in a case-control study using a SNaPSHOT multiplex reaction. Sequencing information from 55 unrelated GSDs with IBD were compared to a control group consisting of 61 unrelated GSDs. The G22A SNP in TLR5 was significantly associated with IBD in GSDs, whereas the remaining two SNPs were found to be significantly protective for IBD. Furthermore, the two SNPs in TLR4 (A1571T and G1807A) were in complete linkage disequilibrium, and were also significantly associated with IBD. The TLR5 risk haplotype (ACC) without the two associated TLR4 SNP alleles was significantly associated with IBD, however the presence of the two TLR4 SNP risk alleles without the TLR5 risk haplotype was not statistically associated with IBD. Our study suggests that the three TLR5 SNPs and two TLR4 SNPs; A1571T and G1807A could play a role in the pathogenesis of IBD in GSDs. Further studies are required to confirm the functional importance of these polymorphisms in the pathogenesis of this disease.

Association between yogurt consumption and the risk of metabolic syndrome over 6 years in the SUN study.

Science.gov (United States)

Sayón-Orea, Carmen; Bes-Rastrollo, Maira; Martí, Amelia; Pimenta, Adriano M; Martín-Calvo, Nerea; Martínez-González, Miguel A

2015-02-21

The role of yogurt consumption in the development of metabolic syndrome (MetS) is not fully understood and the available epidemiologic evidence is scarce. The aim of our study was to assess the association between total, whole-fat, or low-fat yogurt consumption and the risk of developing MetS. Yogurt consumption was assessed at baseline through a 136-item validated FFQ. MetS was defined following the harmonized definition for MetS according to the AHA and the IDF criteria. Logistic regression models were used. During the first 6-y of follow-up of the SUN cohort, 306 incident cases of MetS were identified. Frequent consumption [≥875 g/week (≥7 servings/week) versus ≤ 250 g/week (2 servings/week)] of total, whole-fat and low-fat yogurt consumption showed non-significant inverse associations with MetS [OR = 0.84 (95% CI: 0.60-1.18); 0.98 (95% CI: 0.68-1.41); and 0.63 (95% CI: 0.39-1.02) respectively]. Only one component of the MetS, central adiposity, was inversely associated with total and whole-fat yogurt consumption [OR = 0.85 (95% CI: 0.74-0.98) and 0.85 (95% CI: 0.73-0.99) respectively]. In the joint assessment of exposure to total yogurt consumption and fruit consumption, those in the highest category of total yogurt consumption, and having a high fruit consumption (above the median ≥264.5 g/day) exhibited a significantly lower risk of developing MetS [OR = 0.61 (95% CI: 0.38-0.99)] compared with those in the lowest category of total yogurt consumption and had fruit consumption below the study median. No significant association between yogurt consumption and MetS was apparent. Only one component out of the 5 MetS criteria, central adiposity, was inversely associated with high yogurt consumption. The combination of high consumption of both yogurt and fruit was inversely associated with the development of MetS.

3D Inversion of SQUID Magnetic Tensor Data

DEFF Research Database (Denmark)

Zhdanov, Michael; Cai, Hongzhu; Wilson, Glenn

2012-01-01

Developments in SQUID-based technology have enabled direct measurement of magnetic tensor data for geophysical exploration. For quantitative interpretation, we introduce 3D regularized inversion for magnetic tensor data. For mineral exploration-scale targets, our model studies show that magnetic...... tensor data have significantly improved resolution compared to magnetic vector data for the same model. We present a case study for the 3D regularized inversion of magnetic tensor data acquired over a magnetite skarn at Tallawang, Australia. The results obtained from our 3D regularized inversion agree...

Breast cancer lymphoscintigraphy: Factors associated with sentinel lymph node non visualization.

Science.gov (United States)

Vaz, S C; Silva, Â; Sousa, R; Ferreira, T C; Esteves, S; Carvalho, I P; Ratão, P; Daniel, A; Salgado, L

2015-01-01

To evaluate factors associated with non identification of the sentinel lymph node (SLN) in lymphoscintigraphy of breast cancer patients and analyze the relationship with SLN metastases. A single-center, cross-sectional and retrospective study was performed. Forty patients with lymphoscintigraphy without sentinel lymph node identification (negative lymphoscintigraphy - NL) were enrolled. The control group included 184 patients with SLN identification (positive lymphoscintigraphy - PL). Evaluated factors were age, body mass index (BMI), tumor size, histology, localization, preoperative breast lesion hookwire (harpoon) marking and SLN metastases. The statistical analysis was performed with uni- and multivariate logistic regression models and matched-pairs analysis. Age (p=0.036) or having BMI (p=0.047) were the only factors significantly associated with NL. Being ≥60 years with a BMI ≥30 increased the odds of having a NL 2 and 3.8 times, respectively. Marking with hookwire seems to increase the likelihood of NL, but demonstrated statistical significance is lacking (p=0.087). The other tested variables did not affect the examination result. When controlling for age, BMI and marking with the harpoon, a significant association between lymph node metastization and NL was not found (p=0.565). The most important factors related with non identification of SLN in the patients were age, BMI and marking with hook wire. However, only the first two had statistical importance. When these variables were controlled, no association was found between NL and axillary metastases. Copyright © 2015 Elsevier España, S.L.U. and SEMNIM. All rights reserved.

Inverse Association between Diabetes and Altitude: A Cross Sectional Study in the Adult Population of the United States

Science.gov (United States)

Woolcott, Orison O.; Castillo, Oscar A.; Gutierrez, Cesar; Elashoff, Robert M.; Stefanovski, Darko; Bergman, Richard N.

2014-01-01

Objective To determine whether geographical elevation is inversely associated with diabetes, while adjusting for multiple risk factors. Design and Methods This is a cross-sectional analysis of publicly available online data from the Behavioral Risk Factor Surveillance System, 2009. Final dataset included 285,196 US adult subjects. Odds ratios were obtained from multilevel mixed-effects logistic regression analysis. Results Among US adults (≥20 years old), the odds ratio for diabetes were 1.00 between 0−499 m of altitude (reference), 0.95 (95% confidence interval, 0.90 to 1.01) between 500−1,499 m, and 0.88 (0.81 to 0.96) between 1,500−3,500 m, adjusting for age, sex, body mass index, ethnicity, self-reported fruit and vegetable consumption, self-reported physical activity, current smoking status, level of education, income, health status, employment status, and county-level information on migration rate, urbanization, and latitude. The inverse association between altitude and diabetes in the US was found among men [0.84 (0.76 to 0.94)], but not women [1.09 (0.97 to 1.22)]. Conclusions Among US adults, living at high altitude (1,500−3,500 m) is associated with lower odds of having diabetes than living between 0−499 m, while adjusting for multiple risk factors. Our findings suggest that geographical elevation may be an important factor linked to diabetes. PMID:24890677

Simultaneous inversion of seismic velocity and moment tensor using elastic-waveform inversion of microseismic data: Application to the Aneth CO2-EOR field

Science.gov (United States)

Chen, Y.; Huang, L.

2017-12-01

Moment tensors are key parameters for characterizing CO2-injection-induced microseismic events. Elastic-waveform inversion has the potential to providing accurate results of moment tensors. Microseismic waveforms contains information of source moment tensors and the wave propagation velocity along the wavepaths. We develop an elastic-waveform inversion method to jointly invert the seismic velocity model and moment tensor. We first use our adaptive moment-tensor joint inversion method to estimate moment tensors of microseismic events. Our adaptive moment-tensor inversion method jointly inverts multiple microseismic events with similar waveforms within a cluster to reduce inversion uncertainty for microseismic data recorded using a single borehole geophone array. We use this inversion result as the initial model for our elastic-waveform inversion to minimize the cross-correlated-based data misfit between observed data and synthetic data. We verify our method using synthetic microseismic data and obtain improved results of both moment tensors and seismic velocity model. We apply our new inversion method to microseismic data acquired at a CO2-enhanced oil recovery field in Aneth, Utah, using a single borehole geophone array. The results demonstrate that our new inversion method significantly reduces the data misfit compared to the conventional ray-theory-based moment-tensor inversion.

Support Minimized Inversion of Acoustic and Elastic Wave Scattering

Science.gov (United States)

Safaeinili, Ali

needs to be performed in three areas: (1) exploitation of state-of-the-art parallel computation, (2) improvement of theoretical formulation of the scattering process for better computation efficiency, and (3) development of better methods for guiding the non-linear inversion. (Abstract shortened by UMI.).

Aragonite-Calcite Inversion During Biogenic Carbonate Sampling: Considerations for Interpreting Isotopic Measurements in Paleoclimate Studies

Science.gov (United States)

Waite, A. J.; Swart, P. K.

2011-12-01

As aragonite is the metastable polymorph of calcium carbonate, it lends itself to monotropic inversion to the more stable polymorph, calcite. This inversion is possible through an increase in the temperature and pressure conditions to which the sample is exposed and, although first noted nearly a century ago, has been primarily discussed in the context of sample roasting prior to analyses in paleoclimatological studies. Over the last several decades, however, researchers have found evidence to suggest that the friction associated with the sampling of biogenic carbonates via milling/drilling also induces inversion. Furthermore, this inversion may be associated with a shift in measured oxygen isotopic values and ultimately have significant implications for the interpretation of paleoclimatic reconstructions. Despite this, the isotopic heterogeneity of biogenic aragonite skeletons makes the effects of inversion challenging to test and the subject remains underrepresented in the literature. Here we present a first order study into the effects of milling on both the mineralogy and isotopic compositions measured in sclerosponges, corals, and molluscs. X-Ray diffraction analysis of samples hand ground with a mortar and pestle reveal 100% aragonitic skeletons. Conversely, samples milled with a computerized micromill show measurable inversion to calcite. On average, percent inversion of aragonite to calcite for individual specimens was 15% for sclerosponges, 16% for corals, and 9% for molluscs. Isotopic data from these specimens show that the higher the percentage of aragonite inverted to calcite, the more depleted the measured oxygen isotopic values. In the largest of the datasets (sclerosponges), it is evident that the range of oxygen isotope values from milled samples (-0.02 to +0.84%) exceeds the range in values for those samples which were hand ground and showed no inversion (+0.53 to +0.90%). This, coupled with the strong correlation between the two variables

An inversion disrupting FAM134B is associated with sensory neuropathy in the Border Collie dog breed

OpenAIRE

Forman, Oliver P.; Hitti, Rebekkah J.; Pettitt, Louise; Jenkins, Christopher A.; O'Brien, Dennis P.; Shelton, G. Diane; De Risio, Luisa; Gutierrez Quintana, Rodrigo; Beltran, Elsa; Mellersh, Cathryn

2016-01-01

Sensory neuropathy in the Border Collie is a severe neurological disorder caused by the degeneration of sensory and, to a lesser extent, motor nerve cells with clinical signs starting between 2 and 7 months of age. Using a genome-wide association study approach with three cases and 170 breed matched controls, a suggestive locus for sensory neuropathy was identified that was followed up using a genome sequencing approach. An inversion disrupting the candidate gene FAM134B was identified. Genot...

Plasma mid-regional pro-adrenomedullin levels are inversely associated with anxiety but unrelated to depression: Results from the observational DIAST-CHF study in patients with cardiovascular risk factors.

Science.gov (United States)

Meyer, Thomas; Herrmann-Lingen, Christoph; Chavanon, Mira-Lynn; Pieske, Burkert; Wachter, Rolf; Edelmann, Frank

2015-12-01

It has been postulated that patients with heart failure have a high risk of ventricular arrhythmias and sudden cardiac death resulting from anxiety-induced autonomic arousal. In the prospective and multicenter DIAST-CHF (Diagnostic Trial on Prevalence and Clinical Course of Diastolic Dysfunction and Heart Failure) study, we therefore, tested the hypothesis that adrenomedullin (ADM), a well-established predictor for cardiovascular outcome, is associated with self-rated anxiety symptoms in patients at risk of suffering from or actually with overt heart failure. Study participants with risk factors for diastolic dysfunction were requested to complete the Hospital Anxiety and Depression Scale (HADS), and plasma mid-regional pro-adrenomedullin (MR-proADM) concentrations were measured. In bivariate analysis, we found significantly lower plasma MR-proADM levels in patients with elevated HADS-anxiety scores above the clinically relevant cut-off level of ≥11 (n=118, 536pmol/l, interquartile range [IQR] 449-626) as compared to non-anxious study participants (n=1,292, 573pmol/l, IQR 486-702, p=0.001). A set of multivariate models adjusted for potential confounders confirmed the negative association between self-rated anxiety symptoms and plasma MR-proADM. In similar models, no significant association was detected between HADS-depression scores and MR-proADM. The inverse relationship between plasma MR-proADM and anxiety observed in patients with cardiovascular risk factors supports a previous experimental study using a mutant mouse line with a brain-specific loss of ADM expression which displayed hyperactive and over-anxious behavior. Further experimental and clinical studies are warranted to test the hypothesis that also in humans ADM acts as a neuromodulator with anxiolytic properties. Copyright © 2015. Published by Elsevier Ltd.

Occult pneumothoraces in Chinese patients with significant blunt chest trauma: radiological classification and proposed clinical significance.

Science.gov (United States)

Lee, Ryan K L; Graham, Colin A; Yeung, Janice H H; Ahuja, Anil T; Rainer, Timothy H

2012-12-01

An occult pneumothorax (OP) is a pneumothorax not seen on a supine chest X-ray (CXR) but detected on abdominal or thoracic computed tomography (CT) scanning. With the increasing use of CT in the management of significantly injured trauma patients, more OPs are being detected. The aim of this study was to classify OPs diagnosed on thoracic CT (TCT) and correlate them with their clinical significance. Retrospective analysis of prospectively collected trauma registry data. Total 36 (N=36) consecutive significantly injured trauma patients admitted through the emergency department (ED) who sustained blunt chest trauma and underwent TCT between 1 January 2007 and 31 December 2008 were included. OP was defined as the identification (by a consultant radiologist) of a pneumothorax on TCT that had not been detected on supine CXR. OPs were classified by laterality (unilateral/bilateral) and location (apical, basal, non apical/basal). The size of pneumothoraces, severity of injury [including number of associated thoracic injuries and injury severity score (ISS)], length of hospital stay and mortality were compared between groups. The need for tube thoracostomy and clinical outcome were also analysed. Patients with bilateral OPs (N=8) had significantly more associated thoracic injuries (median: 2 vs. 1, p=0.01), higher ISS (median: 35 vs. 23, p=0.02) and longer hospital stay (median: 20 days vs. 11 days, p=0.01) than those with a unilateral OP (N=28). Basal OPs (N=7) were significantly larger than apical (N=10) and non-apical/basal Ops (N=11). Basal OPs were associated with significantly more associated thoracic injuries (median: 2 vs. 1, p=0.01), higher ISS (median: 35 vs. 25, p=0.04) and longer hospital stays (median: 23 days vs. 17 days, p=0.02) than apical Ops, which had higher ISS (median: 35 vs. 25, p=0.04) and longer hospital stays (median: 23 days vs. 15 days, p=0.02) than non-apical/basal OPs. Non-apical/basal OPs were associated with more related injuries (median: 2

Pet ownership is associated with increased risk of non-atopic asthma and reduced risk of atopy in childhood: findings from a UK birth cohort.

Science.gov (United States)

Collin, S M; Granell, R; Westgarth, C; Murray, J; Paul, E; Sterne, J A C; John Henderson, A

2015-01-01

Studies have shown an inverse association of pet ownership with allergy but inconclusive findings for asthma. To investigate whether pet ownership during pregnancy and childhood was associated with asthma and atopy at the age of 7 in a UK population-based birth cohort. Data from the Avon Longitudinal Study of Parents and Children (ALSPAC) were used to investigate associations of pet ownership at six time points from pregnancy to the age of 7 with asthma, atopy (grass, house dust mite, and cat skin prick test) and atopic vs. non-atopic asthma at the age of 7 using logistic regression models adjusted for child's sex, maternal history of asthma/atopy, maternal smoking during pregnancy, and family adversity. A total of 3768 children had complete data on pet ownership, asthma, and atopy. Compared with non-ownership, continuous ownership of any pet (before and after the age of 3) was associated with 52% lower odds of atopic asthma [odds ratio (OR) 0.48, 95% CI 0.34-0.68]. Pet ownership tended to be associated with increased risk of non-atopic asthma, particularly rabbits (OR 1.61, 1.04-2.51) and rodents (OR 1.86, 1.15-3.01), comparing continuous vs. non-ownership. Pet ownership was consistently associated with lower odds of sensitization to grass, house dust mite, and cat allergens, but rodent ownership was associated with higher odds of sensitization to rodent allergen. Differential effects of pet ownership on atopic vs. non-atopic asthma were evident for all pet types. Pet ownership during pregnancy and childhood in this birth cohort was consistently associated with a reduced risk of aeroallergen sensitization and atopic asthma at the age of 7, but tended to be associated (particularly for rabbits and rodents) with an increased risk of non-atopic asthma. The opposing effects on atopy vs. non-atopic asthma might be considered by parents when they are deciding whether to acquire a pet. © 2014 John Wiley & Sons Ltd.

Forward and Inverse Modeling of Self-potential. A Tomography of Groundwater Flow and Comparison Between Deterministic and Stochastic Inversion Methods

Science.gov (United States)

Quintero-Chavarria, E.; Ochoa Gutierrez, L. H.

2016-12-01

Applications of the Self-potential Method in the fields of Hydrogeology and Environmental Sciences have had significant developments during the last two decades with a strong use on groundwater flows identification. Although only few authors deal with the forward problem's solution -especially in geophysics literature- different inversion procedures are currently being developed but in most cases they are compared with unconventional groundwater velocity fields and restricted to structured meshes. This research solves the forward problem based on the finite element method using the St. Venant's Principle to transform a point dipole, which is the field generated by a single vector, into a distribution of electrical monopoles. Then, two simple aquifer models were generated with specific boundary conditions and head potentials, velocity fields and electric potentials in the medium were computed. With the model's surface electric potential, the inverse problem is solved to retrieve the source of electric potential (vector field associated to groundwater flow) using deterministic and stochastic approaches. The first approach was carried out by implementing a Tikhonov regularization with a stabilized operator adapted to the finite element mesh while for the second a hierarchical Bayesian model based on Markov chain Monte Carlo (McMC) and Markov Random Fields (MRF) was constructed. For all implemented methods, the result between the direct and inverse models was contrasted in two ways: 1) shape and distribution of the vector field, and 2) magnitude's histogram. Finally, it was concluded that inversion procedures are improved when the velocity field's behavior is considered, thus, the deterministic method is more suitable for unconfined aquifers than confined ones. McMC has restricted applications and requires a lot of information (particularly in potentials fields) while MRF has a remarkable response especially when dealing with confined aquifers.

Efficient inverse position transformation for TR 4000S robot manipulator

Directory of Open Access Journals (Sweden)

Kesheng Wang

1989-04-01

Full Text Available An efficient method is developed for computing the inverse kinematic position solution with a closed form for the TR 4000S spray painting robot manipulator with five degrees of freedom and non-spherical wrist construction. The inverse kinematic problem is defined as the transformation from Cartesian space to the joint space. The solution is based on the geometrical separation of the arm and wrist of a robot manipulator and shows that it is very systematic, efficient and easily derived.

Inverse scattering problem in turbulent magnetic fluctuations

Directory of Open Access Journals (Sweden)

R. A. Treumann

2016-08-01

Full Text Available We apply a particular form of the inverse scattering theory to turbulent magnetic fluctuations in a plasma. In the present note we develop the theory, formulate the magnetic fluctuation problem in terms of its electrodynamic turbulent response function, and reduce it to the solution of a special form of the famous Gelfand–Levitan–Marchenko equation of quantum mechanical scattering theory. The last of these applies to transmission and reflection in an active medium. The theory of turbulent magnetic fluctuations does not refer to such quantities. It requires a somewhat different formulation. We reduce the theory to the measurement of the low-frequency electromagnetic fluctuation spectrum, which is not the turbulent spectral energy density. The inverse theory in this form enables obtaining information about the turbulent response function of the medium. The dynamic causes of the electromagnetic fluctuations are implicit to it. Thus, it is of vital interest in low-frequency magnetic turbulence. The theory is developed until presentation of the equations in applicable form to observations of turbulent electromagnetic fluctuations as input from measurements. Solution of the final integral equation should be done by standard numerical methods based on iteration. We point to the possibility of treating power law fluctuation spectra as an example. Formulation of the problem to include observations of spectral power densities in turbulence is not attempted. This leads to severe mathematical problems and requires a reformulation of inverse scattering theory. One particular aspect of the present inverse theory of turbulent fluctuations is that its structure naturally leads to spatial information which is obtained from the temporal information that is inherent to the observation of time series. The Taylor assumption is not needed here. This is a consequence of Maxwell's equations, which couple space and time evolution. The inversion procedure takes

Pericentric inversion of chromosome 12; a three family study

DEFF Research Database (Denmark)

Haagerup, Annette; Hertz, Jens Michael

1992-01-01

A pericentric inversion of chromosome 12 has been followed in three large independently ascertained Danish families. Out of a total number of 52 persons examined, 25 were found to carry the inversion. The breakpoints in all three families were localized to p13 and q13, resulting in more than one...... rate is calculated to be 0.58, which is not significantly different from an expected segregation rate of 0.5. In family 3, an additional inversion of a chromosome 9 has been found in 4 individuals. Our results are discussed in relation to previous findings and with respect to the genetic counselling...... of families with pericentric inversions....

Spectral solution of the inverse Mie problem

Science.gov (United States)

Romanov, Andrey V.; Konokhova, Anastasiya I.; Yastrebova, Ekaterina S.; Gilev, Konstantin V.; Strokotov, Dmitry I.; Chernyshev, Andrei V.; Maltsev, Valeri P.; Yurkin, Maxim A.

2017-10-01

We developed a fast method to determine size and refractive index of homogeneous spheres from the power Fourier spectrum of their light-scattering patterns (LSPs), measured with the scanning flow cytometer. Specifically, we used two spectral parameters: the location of the non-zero peak and zero-frequency amplitude, and numerically inverted the map from the space of particle characteristics (size and refractive index) to the space of spectral parameters. The latter parameters can be reliably resolved only for particle size parameter greater than 11, and the inversion is unique only in the limited range of refractive index with upper limit between 1.1 and 1.25 (relative to the medium) depending on the size parameter and particular definition of uniqueness. The developed method was tested on two experimental samples, milk fat globules and spherized red blood cells, and resulted in accuracy not worse than the reference method based on the least-square fit of the LSP with the Mie theory. Moreover, for particles with significant deviation from the spherical shape the spectral method was much closer to the Mie-fit result than the estimated uncertainty of the latter. The spectral method also showed adequate results for synthetic LSPs of spheroids with aspect ratios up to 1.4. Overall, we present a general framework, which can be used to construct an inverse algorithm for any other experimental signals.

Megabase-Scale Inversion Polymorphism in the Wild Ancestor of Maize

Science.gov (United States)

Fang, Zhou; Pyhäjärvi, Tanja; Weber, Allison L.; Dawe, R. Kelly; Glaubitz, Jeffrey C.; González, José de Jesus Sánchez; Ross-Ibarra, Claudia; Doebley, John; Morrell, Peter L.; Ross-Ibarra, Jeffrey

2012-01-01

Chromosomal inversions are thought to play a special role in local adaptation, through dramatic suppression of recombination, which favors the maintenance of locally adapted alleles. However, relatively few inversions have been characterized in population genomic data. On the basis of single-nucleotide polymorphism (SNP) genotyping across a large panel of Zea mays, we have identified an ∼50-Mb region on the short arm of chromosome 1 where patterns of polymorphism are highly consistent with a polymorphic paracentric inversion that captures >700 genes. Comparison to other taxa in Zea and Tripsacum suggests that the derived, inverted state is present only in the wild Z. mays subspecies parviglumis and mexicana and is completely absent in domesticated maize. Patterns of polymorphism suggest that the inversion is ancient and geographically widespread in parviglumis. Cytological screens find little evidence for inversion loops, suggesting that inversion heterozygotes may suffer few crossover-induced fitness consequences. The inversion polymorphism shows evidence of adaptive evolution, including a strong altitudinal cline, a statistical association with environmental variables and phenotypic traits, and a skewed haplotype frequency spectrum for inverted alleles. PMID:22542971

Inverse association of marijuana use with nonalcoholic fatty liver disease among adults in the United States.

Directory of Open Access Journals (Sweden)

Donghee Kim

Full Text Available The impact of marijuana on nonalcoholic fatty liver disease (NAFLD is largely unknown. We studied the association between marijuana and NAFLD utilizing cross-sectional data from the National Health and Nutrition Examination Survey (NHANES from 2005-2014 and NHANES III (1988-1994.Suspected NAFLD was diagnosed if serum alanine aminotransferase (ALT was > 30 IU/L for men and > 19 IU/L for women in the absence of other liver diseases (NHANES 2005-2014. In NHANES III cohort, NAFLD was defined based on ultrasonography.Of the 14,080 (NHANES 2005-2014 and 8,286 (NHANES III participants, prevalence of suspected NAFLD and ultrasonographically-diagnosed NAFLD were inversely associated with marijuana use (p < 0.001. Compared to marijuana-naïve participants, marijuana users were less likely to have suspected NAFLD (odds ratio [OR]: 0.90, 95% confidence interval [CI]: 0.82-0.99 for past user; OR: 0.68, 95% CI: 0.58-0.80 for current user and ultrasonographically-diagnosed NAFLD (OR: 0.75, 95% CI: 0.57-0.98 for current user in the age, gender, ethnicity-adjusted model. On multivariate analysis, the ORs for suspected NAFLD comparing current light or heavy users to non-users were 0.76 (95% CI 0.58-0.98 and 0.70 (95% CI 0.56-0.89, respectively (P for trend = 0.001 with similar trends in ultrasonographically-diagnosed NAFLD (OR: 0.77, 95% CI: 0.59-1.00 for current user; OR: 0.71, 95% CI: 0.51-0.97 for current light user. In insulin resistance-adjusted model, marijuana use remained an independent predictor of lower risk of suspected NAFLD.In this nationally representative sample, active marijuana use provided a protective effect against NAFLD independent of known metabolic risk factors. The pathophysiology is unclear and warrants further investigation.

Inversion of the Williams syndrome region is a common polymorphism found more frequently in parents of children with Williams syndrome.

Science.gov (United States)

Hobart, Holly H; Morris, Colleen A; Mervis, Carolyn B; Pani, Ariel M; Kistler, Doris J; Rios, Cecilia M; Kimberley, Kendra W; Gregg, Ronald G; Bray-Ward, Patricia

2010-05-15

Williams syndrome (WS) is a multisystem disorder caused by deletion of about 1.55 Mb of DNA (including 26 genes) on chromosome 7q11.23, a region predisposed to recombination due to its genomic structure. Deletion of the Williams syndrome chromosome region (WSCR) occurs sporadically. To better define chance for familial recurrence and to investigate the prevalence of genomic rearrangements of the region, 257 children with WS and their parents were studied. We determined deletion size in probands by metaphase FISH, parent-of-origin of the deleted chromosome by molecular genetic methods, and inversion status of the WSCR in both parents by interphase FISH. The frequency of WSCR inversion in the transmitting parent group was 24.9%. In contrast, the rate of inversion in the non-transmitting parent group (a reasonable estimate of the rate in the general population) was 5.8%. There were no significant gender differences with respect to parent-of-origin for the deleted chromosome or the incidence of the inversion polymorphism. There was no difference in the rate of spontaneous abortion for mothers heterozygous for the WSCR inversion relative to mothers without the inversion. We calculate that for a parent heterozygous for a WSCR inversion, the chance to have a child with WS is about 1 in 1,750, in contrast to the 1 in 9,500 chance for a parent without an inversion.

Stabilizing inverse problems by internal data. II: non-local internal data and generic linearized uniqueness

KAUST Repository

Kuchment, Peter

2015-05-10

© 2015, Springer Basel. In the previous paper (Kuchment and Steinhauer in Inverse Probl 28(8):084007, 2012), the authors introduced a simple procedure that allows one to detect whether and explain why internal information arising in several novel coupled physics (hybrid) imaging modalities could turn extremely unstable techniques, such as optical tomography or electrical impedance tomography, into stable, good-resolution procedures. It was shown that in all cases of interest, the Fréchet derivative of the forward mapping is a pseudo-differential operator with an explicitly computable principal symbol. If one can set up the imaging procedure in such a way that the symbol is elliptic, this would indicate that the problem was stabilized. In the cases when the symbol is not elliptic, the technique suggests how to change the procedure (e.g., by adding extra measurements) to achieve ellipticity. In this article, we consider the situation arising in acousto-optical tomography (also called ultrasound modulated optical tomography), where the internal data available involves the Green’s function, and thus depends globally on the unknown parameter(s) of the equation and its solution. It is shown that the technique of (Kuchment and Steinhauer in Inverse Probl 28(8):084007, 2012) can be successfully adopted to this situation as well. A significant part of the article is devoted to results on generic uniqueness for the linearized problem in a variety of situations, including those arising in acousto-electric and quantitative photoacoustic tomography.

Physiological Aldosterone Concentrations Are Associated with Alterations of Lipid Metabolism: Observations from the General Population

Directory of Open Access Journals (Sweden)

M. Hannich

2018-01-01

Full Text Available Objective. Aldosterone and high-density lipoprotein cholesterol (HDL-C are involved in many pathophysiological processes that contribute to the development of cardiovascular diseases. Previously, associations between the concentrations of aldosterone and certain components of the lipid metabolism in the peripheral circulation were suggested, but data from the general population is sparse. We therefore aimed to assess the associations between aldosterone and HDL-C, low-density lipoprotein cholesterol (LDL-C, total cholesterol, triglycerides, or non-HDL-C in the general adult population. Methods. Data from 793 men and 938 women aged 25–85 years who participated in the first follow-up of the Study of Health in Pomerania were obtained. The associations of aldosterone with serum lipid concentrations were assessed in multivariable linear regression models adjusted for sex, age, body mass index (BMI, estimated glomerular filtration rate (eGFR, and HbA1c. Results. The linear regression models showed statistically significant positive associations of aldosterone with LDL-C (β-coefficient = 0.022, standard error = 0.010, p=0.03 and non-HDL-C (β-coefficient = 0.023, standard error = 0.009, p=0.01 as well as an inverse association of aldosterone with HDL-C (β-coefficient = −0.022, standard error = 0.011, p=0.04. Conclusions. The present data show that plasma aldosterone is positively associated with LDL-C and non-HDL-C and inversely associated with HDL-C in the general population. Our data thus suggests that aldosterone concentrations within the physiological range may be related to alterations of lipid metabolism.

Pericentric Inversion of Chromosome 9 in an Infant With Ambiguous Genitalia.

Science.gov (United States)

Sotoudeh, Arya; Rostami, Parastoo; Nakhaeimoghadam, Maryam; Mohsenipour, Reihaneh; Rezaei, Nima

2017-10-01

Pericentric inversion of Chromosome 9 is one of the most common chromosomal abnormalities, which could be associated with various manifestations in some cases. Herein, a patient is presented with ambiguous genitalia that karyotyping revealed pericentric inversion of Chromosome 9 (p12,q13). Pericentric inversion of Chromosome 9 could be considered in the list of differential diagnosis of those with ambiguous genitalia, while chromosomal karyotype and culture could be recommended in children with ambiguous genitalia.

[Clinic significance of nm23, collage IV and PCNA expression in non-small cell lung cancer].

Science.gov (United States)

Yu, Q; Ma, L; Jing, S; Xu, Y; Geng, D

2001-12-20

To study the significance of nm23, collagen IV and PCNA expressions in non-small cell lung cancer. Expressions of the nm23, collagen IV and PCNA in 84 cases of non-small cell lung cancer were examined with SP immunohistochemical technique. Of the 84 cases, there were squamous cell carcinoma 42, adenocarcinoma 42, stage I 27, stage II 24, stage III 24, and stage IV 9. Statistical analysis was performed with Chi-Square test. Expressions of the nm23, collagen IV and PCNA in 84 cases of non-small cell lung cancer were 60. 7% ( 51/ 84) , 75. 0% ( 63/ 84) and 53. 6% ( 45/ 84) respectively. There was negative correlation between the lymph node metastasis and the expressions of nm23 and collagen IV in squamous cell carcinoma, and the expressions of collagen IV and PCNA were associated with tumor differentiation. No correlation was found between TNM stage and expressions of nm23, collagen IV and PCNA. The results indicate that nm23, collagen IV and PCNA participate the modulation of metastasis of non-small cell lung cancer and that they may be used to evaluate the potential of metastasis.

Generalized inverses theory and computations

CERN Document Server

Wang, Guorong; Qiao, Sanzheng

2018-01-01

This book begins with the fundamentals of the generalized inverses, then moves to more advanced topics. It presents a theoretical study of the generalization of Cramer's rule, determinant representations of the generalized inverses, reverse order law of the generalized inverses of a matrix product, structures of the generalized inverses of structured matrices, parallel computation of the generalized inverses, perturbation analysis of the generalized inverses, an algorithmic study of the computational methods for the full-rank factorization of a generalized inverse, generalized singular value decomposition, imbedding method, finite method, generalized inverses of polynomial matrices, and generalized inverses of linear operators. This book is intended for researchers, postdocs, and graduate students in the area of the generalized inverses with an undergraduate-level understanding of linear algebra.

Seismic stochastic inversion identify river channel sand body

Science.gov (United States)

He, Z.

2015-12-01

The technology of seismic inversion is regarded as one of the most important part of geophysics. By using the technology of seismic inversion and the theory of stochastic simulation, the concept of seismic stochastic inversion is proposed.Seismic stochastic inversion can play an significant role in the identifying river channel sand body. Accurate sand body description is a crucial parameter to measure oilfield development and oilfield stimulation during the middle and later periods. Besides, rational well spacing density is an essential condition for efficient production. Based on the geological knowledge of a certain oilfield, in line with the use of seismic stochastic inversion, the river channel sand body in the work area is identified. In this paper, firstly, the single river channel body from the composite river channel body is subdivided. Secondly, the distribution of river channel body is ascertained in order to ascertain the direction of rivers. Morever, the superimposed relationship among the sand body is analyzed, especially among the inter-well sand body. The last but not at the least, via the analysis of inversion results of first vacuating the wells and continuous infilling later, it is meeted the most needs well spacing density that can obtain the optimal inversion result. It would serve effective guidance for oilfield stimulation.

Inverse modelling of European CH4 emissions during 2006-2012 using different inverse models and reassessed atmospheric observations

Science.gov (United States)

Bergamaschi, Peter; Karstens, Ute; Manning, Alistair J.; Saunois, Marielle; Tsuruta, Aki; Berchet, Antoine; Vermeulen, Alexander T.; Arnold, Tim; Janssens-Maenhout, Greet; Hammer, Samuel; Levin, Ingeborg; Schmidt, Martina; Ramonet, Michel; Lopez, Morgan; Lavric, Jost; Aalto, Tuula; Chen, Huilin; Feist, Dietrich G.; Gerbig, Christoph; Haszpra, László; Hermansen, Ove; Manca, Giovanni; Moncrieff, John; Meinhardt, Frank; Necki, Jaroslaw; Galkowski, Michal; O'Doherty, Simon; Paramonova, Nina; Scheeren, Hubertus A.; Steinbacher, Martin; Dlugokencky, Ed

2018-01-01

We present inverse modelling (top down) estimates of European methane (CH4) emissions for 2006-2012 based on a new quality-controlled and harmonised in situ data set from 18 European atmospheric monitoring stations. We applied an ensemble of seven inverse models and performed four inversion experiments, investigating the impact of different sets of stations and the use of a priori information on emissions. The inverse models infer total CH4 emissions of 26.8 (20.2-29.7) Tg CH4 yr-1 (mean, 10th and 90th percentiles from all inversions) for the EU-28 for 2006-2012 from the four inversion experiments. For comparison, total anthropogenic CH4 emissions reported to UNFCCC (bottom up, based on statistical data and emissions factors) amount to only 21.3 Tg CH4 yr-1 (2006) to 18.8 Tg CH4 yr-1 (2012). A potential explanation for the higher range of top-down estimates compared to bottom-up inventories could be the contribution from natural sources, such as peatlands, wetlands, and wet soils. Based on seven different wetland inventories from the Wetland and Wetland CH4 Inter-comparison of Models Project (WETCHIMP), total wetland emissions of 4.3 (2.3-8.2) Tg CH4 yr-1 from the EU-28 are estimated. The hypothesis of significant natural emissions is supported by the finding that several inverse models yield significant seasonal cycles of derived CH4 emissions with maxima in summer, while anthropogenic CH4 emissions are assumed to have much lower seasonal variability. Taking into account the wetland emissions from the WETCHIMP ensemble, the top-down estimates are broadly consistent with the sum of anthropogenic and natural bottom-up inventories. However, the contribution of natural sources and their regional distribution remain rather uncertain. Furthermore, we investigate potential biases in the inverse models by comparison with regular aircraft profiles at four European sites and with vertical profiles obtained during the Infrastructure for Measurement of the European Carbon

The association between non-Hodgkin lymphoma and organophosphate pesticides exposure: A meta-analysis

International Nuclear Information System (INIS)

Hu, Liqin; Luo, Dan; Zhou, Tingting; Tao, Yun; Feng, Jingwen; Mei, Surong

2017-01-01

Several epidemiological studies show the association between organophosphate pesticides (OPs) and the risk of non-Hodgkin lymphoma (NHL), yet various research results remain controversial. To explore the hazard of OPs exposure to human health, three kinds of OPs (Terbufos, Malathion, and Diazinon) that are non-halogenated aliphatic compounds were included in the meta-analysis. We searched PubMed and Web of Science Databases for articles published from 1985 to February 2017. The databases were also searched for eligible studies through a manual references search. The random-effect model was utilized to compute the odds ratios (ORs) and 95% confident intervals (CIs). A total of ten observational studies (five cohort, four case-control, and one nested case-control) were included in our meta-analysis, with a pooled OR of 1.22 (95% CI 1.04 to 1.43) of Malathion, Terbufos and Diazinion. The general heterogeneity for OR was moderate (P h  = 0.032, I 2  = 41.2%). The OR estimates in the subset analyses were utilized to compare the association between the three kinds of OPs and NHL; Terbufos (OR = 1.07, 95% CI 0.85 to 1.36) and Malathion (OR = 1.17, 95% CI 0.82 to 1.67) had a statistically non-significant relationship, whereas Diazinon (OR = 1.39, 95% CI 1.11 to 1.73) was significantly associated with an increased NHL risk. Because immune dysfunction was thought to increase NHL risk, the toxicity levels in the immune system of the three types of OPs were compared. Malathion attacked immune cells via a direct effect and Diazinon disrupted the neuro-immune system, which involves the cholinergic system of lymphocytes via indirect immune damage, whereas an immunotoxic effect involving Terbufos was not reported. Overall, the present meta-analysis indicated a statistically significant association between Diazinon exposure and NHL risk. - Highlights: • The present meta-analysis indicated a significantly positive association between Diazinon exposure and NHL risk.

Stochastic forward and inverse groundwater flow and solute transport modeling

NARCIS (Netherlands)

Janssen, G.M.C.M.

2008-01-01

Keywords: calibration, inverse modeling, stochastic modeling, nonlinear biodegradation, stochastic-convective, advective-dispersive, travel time, network design, non-Gaussian distribution, multimodal distribution, representers

This thesis offers three new approaches that contribute

Carleman estimates and applications to inverse problems for hyperbolic systems

CERN Document Server

Bellassoued, Mourad

2017-01-01

This book is a self-contained account of the method based on Carleman estimates for inverse problems of determining spatially varying functions of differential equations of the hyperbolic type by non-overdetermining data of solutions. The formulation is different from that of Dirichlet-to-Neumann maps and can often prove the global uniqueness and Lipschitz stability even with a single measurement. These types of inverse problems include coefficient inverse problems of determining physical parameters in inhomogeneous media that appear in many applications related to electromagnetism, elasticity, and related phenomena. Although the methodology was created in 1981 by Bukhgeim and Klibanov, its comprehensive development has been accomplished only recently. In spite of the wide applicability of the method, there are few monographs focusing on combined accounts of Carleman estimates and applications to inverse problems. The aim in this book is to fill that gap. The basic tool is Carleman estimates, the theory of wh...

Improving the reliability of POD curves in NDI methods using a Bayesian inversion approach for uncertainty quantification

Science.gov (United States)

Ben Abdessalem, A.; Jenson, F.; Calmon, P.

2016-02-01

This contribution provides an example of the possible advantages of adopting a Bayesian inversion approach to uncertainty quantification in nondestructive inspection methods. In such problem, the uncertainty associated to the random parameters is not always known and needs to be characterised from scattering signal measurements. The uncertainties may then correctly propagated in order to determine a reliable probability of detection curve. To this end, we establish a general Bayesian framework based on a non-parametric maximum likelihood function formulation and some priors from expert knowledge. However, the presented inverse problem is time-consuming and computationally intensive. To cope with this difficulty, we replace the real model by a surrogate one in order to speed-up the model evaluation and to make the problem to be computationally feasible for implementation. The least squares support vector regression is adopted as metamodelling technique due to its robustness to deal with non-linear problems. We illustrate the usefulness of this methodology through the control of tube with enclosed defect using ultrasonic inspection method.

Refraction traveltime tomography with irregular topography using the unwrapped phase inversion

KAUST Repository

Choi, Yun Seok

2013-01-01

Traveltime tomography has long served as a stable and efficient tool for velocity estimation, especially for the near surface. It, however, suffers from some of limitations associated with ray tracing and high-frequency traveltime in velocity inversion zones and ray shadow regions. We develop a tomographic approach based on traveltime solutions obtained by tracking the phase (instantaneous traveltime) of the wavefield solution of the Helmholtz wave equation. Since the instantaneous-traveltime does not suffer from phase wrapping, the inversion algorithm using the instantaneous-traveltime has the potential to generate robust inversion results. With a high damping factor, the instantaneous-traveltime inversion provides refraction tomography similar results, but from a single frequency. Despite the Helmholtz-based solver implementation, the tomographic inversion handles irrgular topography. The numerical examples show that our inversion algorithm generates a convergent smooth velocity model, which looks very much like a tomographic result. Next, we plan to apply the instantaneous-traveltime inversion algorithm to real seismic data acquired from the near surface with irregular topography.

Risk factors associated with allergic and non-allergic asthma in adolescents.

Science.gov (United States)

Janson, Christer; Kalm-Stephens, Pia; Foucard, Tony; Alving, Kjell; Nordvall, S Lennart

2007-07-01

Risk factors for asthma have been investigated in a large number of studies in adults and children, with little progress in the primary and secondary prevention of asthma. The aim of this investigation was to investigate risk factors associated with allergic and non-allergic asthma in adolescents. In this study, 959 schoolchildren (13-14 years old) answered a questionnaire and performed exhaled nitric oxide (NO) measurements. All children (n = 238) with reported asthma, asthma-related symptoms and/or increased NO levels were invited to a clinical follow-up which included a physician evaluation and skin-prick testing. Asthma was diagnosed in 96 adolescents, whereof half had allergic and half non-allergic asthma. Children with both allergic and non-allergic asthma had a significantly higher body mass index (BMI) (20.8 and 20.7 vs. 19.8 kg/m(2)) (p < 0.05) and a higher prevalence of parental asthma (30% and 32% vs. 16%) (p < 0.05). Early-life infection (otitis and croup) [adjusted odds ratio (OR) (95% confidence interval (CI)): 1.99 (1.02-3.88) and 2.80 (1.44-5.42), respectively], pets during the first year of life [2.17 (1.16-4.04)], window pane condensation [2.45 (1.11-5.40)] and unsatisfactory school cleaning [(2.50 (1.28-4.89)] was associated with non-allergic but not with allergic asthma. This study indicates the importance of distinguishing between subtypes of asthma when assessing the effect of different risk factors. While the risk of both allergic and non-allergic asthma increased with increasing BMI, associations between early-life and current environmental exposure were primarily found in relation to non-allergic asthma.

Some results on inverse scattering

International Nuclear Information System (INIS)

Ramm, A.G.

2008-01-01

A review of some of the author's results in the area of inverse scattering is given. The following topics are discussed: (1) Property C and applications, (2) Stable inversion of fixed-energy 3D scattering data and its error estimate, (3) Inverse scattering with 'incomplete' data, (4) Inverse scattering for inhomogeneous Schroedinger equation, (5) Krein's inverse scattering method, (6) Invertibility of the steps in Gel'fand-Levitan, Marchenko, and Krein inversion methods, (7) The Newton-Sabatier and Cox-Thompson procedures are not inversion methods, (8) Resonances: existence, location, perturbation theory, (9) Born inversion as an ill-posed problem, (10) Inverse obstacle scattering with fixed-frequency data, (11) Inverse scattering with data at a fixed energy and a fixed incident direction, (12) Creating materials with a desired refraction coefficient and wave-focusing properties. (author)

3D stochastic inversion and joint inversion of potential fields for multi scale parameters

Science.gov (United States)

Shamsipour, Pejman

In this thesis we present the development of new techniques for the interpretation of potential field (gravity and magnetic data), which are the most widespread economic geophysical methods used for oil and mineral exploration. These new techniques help to address the long-standing issue with the interpretation of potential fields, namely the intrinsic non-uniqueness inversion of these types of data. The thesis takes the form of three papers (four including Appendix), which have been published, or soon to be published, in respected international journals. The purpose of the thesis is to introduce new methods based on 3D stochastical approaches for: 1) Inversion of potential field data (magnetic), 2) Multiscale Inversion using surface and borehole data and 3) Joint inversion of geophysical potential field data. We first present a stochastic inversion method based on a geostatistical approach to recover 3D susceptibility models from magnetic data. The aim of applying geostatistics is to provide quantitative descriptions of natural variables distributed in space or in time and space. We evaluate the uncertainty on the parameter model by using geostatistical unconditional simulations. The realizations are post-conditioned by cokriging to observation data. In order to avoid the natural tendency of the estimated structure to lay near the surface, depth weighting is included in the cokriging system. Then, we introduce algorithm for multiscale inversion, the presented algorithm has the capability of inverting data on multiple supports. The method involves four main steps: i. upscaling of borehole parameters (It could be density or susceptibility) to block parameters, ii. selection of block to use as constraints based on a threshold on kriging variance, iii. inversion of observation data with selected block densities as constraints, and iv. downscaling of inverted parameters to small prisms. Two modes of application are presented: estimation and simulation. Finally, a novel

Towards the mechanical characterization of abdominal wall by inverse analysis.

Science.gov (United States)

Simón-Allué, R; Calvo, B; Oberai, A A; Barbone, P E

2017-02-01

The aim of this study is to characterize the passive mechanical behaviour of abdominal wall in vivo in an animal model using only external cameras and numerical analysis. The main objective lies in defining a methodology that provides in vivo information of a specific patient without altering mechanical properties. It is demonstrated in the mechanical study of abdomen for hernia purposes. Mechanical tests consisted on pneumoperitoneum tests performed on New Zealand rabbits, where inner pressure was varied from 0mmHg to 12mmHg. Changes in the external abdominal surface were recorded and several points were tracked. Based on their coordinates we reconstructed a 3D finite element model of the abdominal wall, considering an incompressible hyperelastic material model defined by two parameters. The spatial distributions of these parameters (shear modulus and non linear parameter) were calculated by inverse analysis, using two different types of regularization: Total Variation Diminishing (TVD) and Tikhonov (H 1 ). After solving the inverse problem, the distribution of the material parameters were obtained along the abdominal surface. Accuracy of the results was evaluated for the last level of pressure. Results revealed a higher value of the shear modulus in a wide stripe along the craneo-caudal direction, associated with the presence of linea alba in conjunction with fascias and rectus abdominis. Non linear parameter distribution was smoother and the location of higher values varied with the regularization type. Both regularizations proved to yield in an accurate predicted displacement field, but H 1 obtained a smoother material parameter distribution while TVD included some discontinuities. The methodology here presented was able to characterize in vivo the passive non linear mechanical response of the abdominal wall. Copyright © 2016 Elsevier Ltd. All rights reserved.

[Frequency of atypical squamous cells of undetermined significance (ASCUS) for pregnant and non-pregnant women].

Science.gov (United States)

Dufloth, Rozany Mucha; Vieira, Luiz Fernando Fonseca; Xavier Júnior, José Candido Caldeira; Vale, Diama Bhadra; Zeferino, Luiz Carlos

2015-05-01

To compare the frequency of an ASCUS Pap Smear result in pregnant and non-pregnant women, stratified by age group. We analyzed the results of 1,336,180 cytopathologyc exams of Pap smears performed between 2000 and 2009 (ten years) with the purpose of screening for cervical carcinoma. Comparisons were made between pregnant and non-pregnant women, and the sample was stratified into three age groups (20-24, 25-29 and 30-34 years). The χ2 test was used and the magnitude of association was determined by the by Odds Ratio (OR) with the 95% confidence interval (95%CI). A Total of 447,489 samples were excluded on the basis of the criteria adopted, for a total final sample of 37,137 pregnant women and 851,554 non-pregnant women. An ASCUS result was detected in 1.2% of cases, with a significant difference between pregnant and non-pregnant women in the age groups of 20-24 years (OR=0.85; 95%CI 0.75-0.97) and 25-29 years (OR=0.78; 95%CI 0.63-0.96). There was no difference in the group between 30-34 years (OR=0.76; 95%CI 0.57-1.03). This study suggested that non-pregnant women have a higher frequency of ASCUS, most evident in the age group of 20 to 29 years. The collection of cervical cancer screening should not be a compulsory part of the prenatal routine.

Iterative algorithms for the input and state recovery from the approximate inverse of strictly proper multivariable systems

Science.gov (United States)

Chen, Liwen; Xu, Qiang

2018-02-01

This paper proposes new iterative algorithms for the unknown input and state recovery from the system outputs using an approximate inverse of the strictly proper linear time-invariant (LTI) multivariable system. One of the unique advantages from previous system inverse algorithms is that the output differentiation is not required. The approximate system inverse is stable due to the systematic optimal design of a dummy feedthrough D matrix in the state-space model via the feedback stabilization. The optimal design procedure avoids trial and error to identify such a D matrix which saves tremendous amount of efforts. From the derived and proved convergence criteria, such an optimal D matrix also guarantees the convergence of algorithms. Illustrative examples show significant improvement of the reference input signal tracking by the algorithms and optimal D design over non-iterative counterparts on controllable or stabilizable LTI systems, respectively. Case studies of two Boeing-767 aircraft aerodynamic models further demonstrate the capability of the proposed methods.

A modified Mediterranean diet score is inversely associated with metabolic syndrome in Korean adults.

Science.gov (United States)

Kim, Youngyo; Je, Youjin

2018-03-21

Findings from studies in Western countries showed that Mediterranean diet is inversely associated with metabolic syndrome, but little is known about this association in Asian countries. To evaluate the association between Mediterranean diet and metabolic syndrome in Korean population, this study was conducted. A total of 8387 adults 19-64 years of age from the Korea National Health and Nutrition Examination Survey 2012-2015 were assessed. A 112-item dish-based semiquantitative food frequency questionnaire was used to assess dietary intakes. Mediterranean diet was assessed by a modified Mediterranean diet score, which was based on the alternate Mediterranean diet score of Fung et al. Multivariable logistic regression models were used to calculate odds ratios (ORs) with 95% confidence intervals (CIs) adjusted for other dietary and lifestyle variables. Participants with 5-6 and 7 or higher modified Mediterranean diet scores had a lower prevalence of metabolic syndrome by 27% (OR = 0.73, 95% CI: 0.56-0.96) and 36% (OR = 0.64, 95% CI: 0.46-0.89; P-trend = 0.0031), compared with those with 2 or lower modified Mediterranean diet scores, respectively. Higher modified Mediterranean diet scores were associated with a lower prevalence of abdominal obesity and hypertriglyceridemia, which are components of metabolic syndrome CONCLUSIONS: Our findings suggest that diet rich in fruit, vegetables, whole grains, legumes, peanuts and fish is associated with a lower prevalence of metabolic syndrome in Korean adults.

Schistosome infection intensity is inversely related to auto-reactive antibody levels.

Directory of Open Access Journals (Sweden)

Francisca Mutapi

2011-05-01

Full Text Available In animal experimental models, parasitic helminth infections can protect the host from auto-immune diseases. We conducted a population-scale human study investigating the relationship between helminth parasitism and auto-reactive antibodies and the subsequent effect of anti-helminthic treatment on this relationship. Levels of antinuclear antibodies (ANA and plasma IL-10 were measured by enzyme linked immunosorbent assay in 613 Zimbabweans (aged 2-86 years naturally exposed to the blood fluke Schistosoma haematobium. ANA levels were related to schistosome infection intensity and systemic IL-10 levels. All participants were offered treatment with the anti-helminthic drug praziquantel and 102 treated schoolchildren (5-16 years were followed up 6 months post-antihelminthic treatment. ANA levels were inversely associated with current infection intensity but were independent of host age, sex and HIV status. Furthermore, after allowing for the confounding effects of schistosome infection intensity, ANA levels were inversely associated with systemic levels of IL-10. ANA levels increased significantly 6 months after anti-helminthic treatment. Our study shows that ANA levels are attenuated in helminth-infected humans and that anti-helminthic treatment of helminth-infected people can significantly increase ANA levels. The implications of these findings are relevant for understanding both the aetiology of immune disorders mediated by auto-reactive antibodies and in predicting the long-term consequences of large-scale schistosomiasis control programs.

Exploration of Deregulated Long Non-Coding RNAs in Association with Hepatocarcinogenesis and Survival

Energy Technology Data Exchange (ETDEWEB)

Shen, Jing, E-mail: js2182@cumc.columbia.edu [Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University Medical Center, New York, NY 10032 (United States); Herbert Irving Comprehensive Cancer Center, Columbia University Medical Center, New York, NY 10032 (United States); Siegel, Abby B. [Herbert Irving Comprehensive Cancer Center, Columbia University Medical Center, New York, NY 10032 (United States); Department of Medicine, Columbia University Medical Center, New York, NY 10032 (United States); Remotti, Helen [Department of Pathology and Cell Biology, Columbia University Medical Center, New York, NY 10032 (United States); Wang, Qiao; Shen, Yueyue [Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University Medical Center, New York, NY 10032 (United States); Santella, Regina M. [Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University Medical Center, New York, NY 10032 (United States); Herbert Irving Comprehensive Cancer Center, Columbia University Medical Center, New York, NY 10032 (United States)

2015-09-10

Long non-coding RNAs (lncRNAs) are larger than 200 nucleotides in length and pervasively expressed across the genome. An increasing number of studies indicate that lncRNA transcripts play integral regulatory roles in cellular growth, division, differentiation and apoptosis. Deregulated lncRNAs have been observed in a variety of human cancers, including hepatocellular carcinoma (HCC). We determined the expression profiles of 90 lncRNAs for 65 paired HCC tumor and adjacent non-tumor tissues, and 55 lncRNAs were expressed in over 90% of samples. Eight lncRNAs were significantly down-regulated in HCC tumor compared to non-tumor tissues (p < 0.05), but no lncRNA achieved statistical significance after Bonferroni correction for multiple comparisons. Within tumor tissues, carrying more aberrant lncRNAs (6–7) was associated with a borderline significant reduction in survival (HR = 8.5, 95% CI: 1.0–72.5). The predictive accuracy depicted by the AUC was 0.93 for HCC survival when using seven deregulated lncRNAs (likelihood ratio test p = 0.001), which was similar to that combining the seven lncRNAs with tumor size and treatment (AUC = 0.96, sensitivity = 87%, specificity = 87%). These data suggest the potential association of deregulated lncRNAs with hepatocarcinogenesis and HCC survival.

Calculation of the inverse data space via sparse inversion

KAUST Repository

Saragiotis, Christos; Doulgeris, Panagiotis C.; Verschuur, Dirk Jacob Eric

2011-01-01

The inverse data space provides a natural separation of primaries and surface-related multiples, as the surface multiples map onto the area around the origin while the primaries map elsewhere. However, the calculation of the inverse data is far from

Palaeocene-early Eocene inversion of the Phuquoc-Kampot Som Basin

DEFF Research Database (Denmark)

Fyhn, Michael B. W.; Pedersen, Stig A.S.; Boldreel, Lars Ole

2010-01-01

/Pb analysis is used to unravel the basin history. This reveals a hitherto unknown earliest Palaeogene basin inversion associated with the Luconian suturing to SE Asia and the shutdown of palaeo-Pacific subduction underneath SE Asia. The Phuquoc–Kampot Som Basin and the Khorat Basin in Thailand constitute...... the erosional remnants of a larger basin that covered large parts of SE Asia in Late Mesozoic time, and subsequently became segregated during earliest Palaeogene inversion and erosion. Inversion was focused along the several hundred kilometres long Kampot and Khmer–Chanthaburi fold belts that confine...

The non-biphenyl-tetrazole angiotensin AT1 receptor antagonist eprosartan is a unique and robust inverse agonist of the active state of the AT1 receptor.

Science.gov (United States)

Takezako, Takanobu; Unal, Hamiyet; Karnik, Sadashiva S; Node, Koichi

2018-03-23

Conditions such as hypertension and renal allograft rejection are accompanied by chronic, agonist-independent, signalling by angiotensin II AT 1 receptors. The current treatment paradigm for these diseases entails the preferred use of inverse agonist AT 1 receptor blockers (ARBs). However, variability in the inverse agonist activities of common biphenyl-tetrazole ARBs for the active state of AT 1 receptors often leads to treatment failure. Therefore, characterization of robust inverse agonist ARBs for the active state of AT 1 receptors is necessary. To identify the robust inverse agonist for active state of AT 1 receptors and its molecular mechanism, we performed site-directed mutagenesis, competition binding assay, inositol phosphate production assay and molecular modelling for both ground-state wild-type AT 1 receptors and active-state N111G mutant AT 1 receptors. Although candesartan and telmisartan exhibited weaker inverse agonist activity for N111G- compared with WT-AT 1 receptors, only eprosartan exhibited robust inverse agonist activity for both N111G- and WT- AT 1 receptors. Specific ligand-receptor contacts for candesartan and telmisartan are altered in the active-state N111G- AT 1 receptors compared with the ground-state WT-AT 1 receptors, suggesting an explanation of their attenuated inverse agonist activity for the active state of AT 1 receptors. In contrast, interactions between eprosartan and N111G-AT 1 receptors were not significantly altered, and the inverse agonist activity of eprosartan was robust. Eprosartan may be a better therapeutic option than other ARBs. Comparative studies investigating eprosartan and other ARBs for the treatment of diseases caused by chronic, agonist-independent, AT 1 receptor activation are warranted. © 2018 The British Pharmacological Society.

Fully probabilistic seismic source inversion – Part 1: Efficient parameterisation

Directory of Open Access Journals (Sweden)

S. C. Stähler

2014-11-01

Full Text Available Seismic source inversion is a non-linear problem in seismology where not just the earthquake parameters themselves but also estimates of their uncertainties are of great practical importance. Probabilistic source inversion (Bayesian inference is very adapted to this challenge, provided that the parameter space can be chosen small enough to make Bayesian sampling computationally feasible. We propose a framework for PRobabilistic Inference of Seismic source Mechanisms (PRISM that parameterises and samples earthquake depth, moment tensor, and source time function efficiently by using information from previous non-Bayesian inversions. The source time function is expressed as a weighted sum of a small number of empirical orthogonal functions, which were derived from a catalogue of >1000 source time functions (STFs by a principal component analysis. We use a likelihood model based on the cross-correlation misfit between observed and predicted waveforms. The resulting ensemble of solutions provides full uncertainty and covariance information for the source parameters, and permits propagating these source uncertainties into travel time estimates used for seismic tomography. The computational effort is such that routine, global estimation of earthquake mechanisms and source time functions from teleseismic broadband waveforms is feasible.

Maximum a posteriori probability estimates in infinite-dimensional Bayesian inverse problems

International Nuclear Information System (INIS)

Helin, T; Burger, M

2015-01-01

A demanding challenge in Bayesian inversion is to efficiently characterize the posterior distribution. This task is problematic especially in high-dimensional non-Gaussian problems, where the structure of the posterior can be very chaotic and difficult to analyse. Current inverse problem literature often approaches the problem by considering suitable point estimators for the task. Typically the choice is made between the maximum a posteriori (MAP) or the conditional mean (CM) estimate. The benefits of either choice are not well-understood from the perspective of infinite-dimensional theory. Most importantly, there exists no general scheme regarding how to connect the topological description of a MAP estimate to a variational problem. The recent results by Dashti and others (Dashti et al 2013 Inverse Problems 29 095017) resolve this issue for nonlinear inverse problems in Gaussian framework. In this work we improve the current understanding by introducing a novel concept called the weak MAP (wMAP) estimate. We show that any MAP estimate in the sense of Dashti et al (2013 Inverse Problems 29 095017) is a wMAP estimate and, moreover, how the wMAP estimate connects to a variational formulation in general infinite-dimensional non-Gaussian problems. The variational formulation enables to study many properties of the infinite-dimensional MAP estimate that were earlier impossible to study. In a recent work by the authors (Burger and Lucka 2014 Maximum a posteriori estimates in linear inverse problems with logconcave priors are proper bayes estimators preprint) the MAP estimator was studied in the context of the Bayes cost method. Using Bregman distances, proper convex Bayes cost functions were introduced for which the MAP estimator is the Bayes estimator. Here, we generalize these results to the infinite-dimensional setting. Moreover, we discuss the implications of our results for some examples of prior models such as the Besov prior and hierarchical prior. (paper)

Inverse Limits

CERN Document Server

Ingram, WT

2012-01-01

Inverse limits provide a powerful tool for constructing complicated spaces from simple ones. They also turn the study of a dynamical system consisting of a space and a self-map into a study of a (likely more complicated) space and a self-homeomorphism. In four chapters along with an appendix containing background material the authors develop the theory of inverse limits. The book begins with an introduction through inverse limits on [0,1] before moving to a general treatment of the subject. Special topics in continuum theory complete the book. Although it is not a book on dynamics, the influen

Nested Inversion Polymorphisms Predispose Chromosome 22q11.2 to Meiotic Rearrangements.

Science.gov (United States)

Demaerel, Wolfram; Hestand, Matthew S; Vergaelen, Elfi; Swillen, Ann; López-Sánchez, Marcos; Pérez-Jurado, Luis A; McDonald-McGinn, Donna M; Zackai, Elaine; Emanuel, Beverly S; Morrow, Bernice E; Breckpot, Jeroen; Devriendt, Koenraad; Vermeesch, Joris R

2017-10-05

Inversion polymorphisms between low-copy repeats (LCRs) might predispose chromosomes to meiotic non-allelic homologous recombination (NAHR) events and thus lead to genomic disorders. However, for the 22q11.2 deletion syndrome (22q11.2DS), the most common genomic disorder, no such inversions have been uncovered as of yet. Using fiber-FISH, we demonstrate that parents transmitting the de novo 3 Mb LCR22A-D 22q11.2 deletion, the reciprocal duplication, and the smaller 1.5 Mb LCR22A-B 22q11.2 deletion carry inversions of LCR22B-D or LCR22C-D. Hence, the inversions predispose chromosome 22q11.2 to meiotic rearrangements and increase the individual risk for transmitting rearrangements. Interestingly, the inversions are nested or flanking rather than coinciding with the deletion or duplication sizes. This finding raises the possibility that inversions are a prerequisite not only for 22q11.2 rearrangements but also for all NAHR-mediated genomic disorders. Copyright © 2017. Published by Elsevier Inc.

Nonlinear problems in fluid dynamics and inverse scattering: Nonlinear waves and inverse scattering

Science.gov (United States)

Ablowitz, Mark J.

1994-12-01

Research investigations involving the fundamental understanding and applications of nonlinear wave motion and related studies of inverse scattering and numerical computation have been carried out and a number of significant results have been obtained. A class of nonlinear wave equations which can be solved by the inverse scattering transform (IST) have been studied, including the Kadaomtsev-Petviashvili (KP) equation, the Davey-Stewartson equation, and the 2+1 Toda system. The solutions obtained by IST correspond to the Cauchy initial value problem with decaying initial data. We have also solved two important systems via the IST method: a 'Volterra' system in 2+1 dimensions and a new one dimensional nonlinear equation which we refer to as the Toda differential-delay equation. Research in computational chaos in moderate to long time numerical simulations continues.

Inverse problems of geophysics

International Nuclear Information System (INIS)

Yanovskaya, T.B.

2003-07-01

This report gives an overview and the mathematical formulation of geophysical inverse problems. General principles of statistical estimation are explained. The maximum likelihood and least square fit methods, the Backus-Gilbert method and general approaches for solving inverse problems are discussed. General formulations of linearized inverse problems, singular value decomposition and properties of pseudo-inverse solutions are given

Independent and joint effects of tea and milk consumption on oral cancer among non-smokers and non-drinkers: a case-control study in China.

Science.gov (United States)

Chen, Fa; Yan, Lingjun; Lin, Lisong; Liu, Fengqiong; Qiu, Yu; Liu, Fangping; Huang, Jiangfeng; Wu, Junfeng; Cai, Lin; Cai, Guoxi; Aoyagi, Kiyoshi; He, Baochang

2017-07-25

This study aims to evaluate the independent and joint effects of tea and milk consumption on oral cancer risk among non-smokers and non-drinkers (NS/ND). A hospital-based case-control study was performed in Fujian, China. 421 cases and frequency-matched 1398 controls were included without tobacco smoking and alcohol drinking habits. Unconditional logistic regression model was used to assess the relationship of tea and milk consumption with oral cancer risk. Tea and milk consumption were significantly associated with decreased risk of oral cancer, the adjusted odds ratios (aORs) were 0.73 (95% CI: 0.54-0.97) and 0.69 (95% CI: 0.55-0.88), respectively. According to subgroup analysis, the inverse associations between tea consumption and oral cancer risk were only observed among the elders (>60 years) and urban residents. While the protect effect of milk drinking was more obvious in males, normal body mass index population (18.5-23.9), urban residents and those age ≤ 60 years. Additionally, a significantly multiplicative interaction between tea and milk consumption was observed for oral cancer risk (P = 0.001). The present study is the first to simultaneously assess the association of tea consumption and milk drinking with oral cancer risk. The results suggest that tea and milk consumption are independent protective factors for oral cancer among NS/ND, with a joint effect between them.

Significance of non-classical damping in seismic qualification of equipment and piping

Energy Technology Data Exchange (ETDEWEB)

Gupta, Abhinav, E-mail: agupta1@ncsu.edu; Bose, Mrinal K.

2017-06-15

Highlights: • Damping in coupled building-piping or building-equipment systems is nonlclassical. • Significance of nonclassical damping is illustrated. • Classical damping assumption can over predict or under predict response. • Significance of nonclassical damping increases for very light secondary systems. • Composite modal damping is another form of classical damping. - Abstract: This paper presents a discussion on the significance of non-classical damping in coupled primary-secondary systems such as building-equipment or building-piping. Closed-form expressions are used to illustrate that the effect of non-classical damping is significant in systems with tuned or nearly tuned uncoupled modes when the mass-interaction is sufficiently small. Further, simple primary-secondary systems are used to illustrate that composite modal damping is another form of classical damping for which the transformed damping matrix, obtained after pre- and post-multiplication of the damping matrix with the modal matrix, contains only diagonal terms. Both the composite and the classical damping give almost identical results that can be much different from the corresponding results for non-classical damping. Finally, it is shown that consideration of classical damping (ignoring the off-diagonal terms) can give excessively conservative results in nearly tuned primary-secondary systems. For perfectly tuned primary-secondary systems, however, classical damping can give responses that are much lower than what they should be.

Reconstruction Methods for Inverse Problems with Partial Data

DEFF Research Database (Denmark)

Hoffmann, Kristoffer

This thesis presents a theoretical and numerical analysis of a general mathematical formulation of hybrid inverse problems in impedance tomography. This includes problems from several existing hybrid imaging modalities such as Current Density Impedance Imaging, Magnetic Resonance Electrical...... Impedance Tomography, and Ultrasound Modulated Electrical Impedance Tomography. After giving an introduction to hybrid inverse problems in impedance tomography and the mathematical tools that facilitate the related analysis, we explain in detail the stability properties associated with the classification...... of a linearised hybrid inverse problem. This is done using pseudo-differential calculus and theory for overdetermined boundary value problem. Using microlocal analysis we then present novel results on the propagation of singularities, which give a precise description of the distinct features of solutions...

Identification of source velocities on 3D structures in non-anechoic environments: Theoretical background and experimental validation of the inverse patch transfer functions method

Science.gov (United States)

Aucejo, M.; Totaro, N.; Guyader, J.-L.

2010-08-01

In noise control, identification of the source velocity field remains a major problem open to investigation. Consequently, methods such as nearfield acoustical holography (NAH), principal source projection, the inverse frequency response function and hybrid NAH have been developed. However, these methods require free field conditions that are often difficult to achieve in practice. This article presents an alternative method known as inverse patch transfer functions, designed to identify source velocities and developed in the framework of the European SILENCE project. This method is based on the definition of a virtual cavity, the double measurement of the pressure and particle velocity fields on the aperture surfaces of this volume, divided into elementary areas called patches and the inversion of impedances matrices, numerically computed from a modal basis obtained by FEM. Theoretically, the method is applicable to sources with complex 3D geometries and measurements can be carried out in a non-anechoic environment even in the presence of other stationary sources outside the virtual cavity. In the present paper, the theoretical background of the iPTF method is described and the results (numerical and experimental) for a source with simple geometry (two baffled pistons driven in antiphase) are presented and discussed.

Inverse kinematics problem in robotics using neural networks

Science.gov (United States)

Choi, Benjamin B.; Lawrence, Charles

1992-01-01

In this paper, Multilayer Feedforward Networks are applied to the robot inverse kinematic problem. The networks are trained with endeffector position and joint angles. After training, performance is measured by having the network generate joint angles for arbitrary endeffector trajectories. A 3-degree-of-freedom (DOF) spatial manipulator is used for the study. It is found that neural networks provide a simple and effective way to both model the manipulator inverse kinematics and circumvent the problems associated with algorithmic solution methods.

Geostatistical regularization operators for geophysical inverse problems on irregular meshes

Science.gov (United States)

Jordi, C.; Doetsch, J.; Günther, T.; Schmelzbach, C.; Robertsson, J. OA

2018-05-01

Irregular meshes allow to include complicated subsurface structures into geophysical modelling and inverse problems. The non-uniqueness of these inverse problems requires appropriate regularization that can incorporate a priori information. However, defining regularization operators for irregular discretizations is not trivial. Different schemes for calculating smoothness operators on irregular meshes have been proposed. In contrast to classical regularization constraints that are only defined using the nearest neighbours of a cell, geostatistical operators include a larger neighbourhood around a particular cell. A correlation model defines the extent of the neighbourhood and allows to incorporate information about geological structures. We propose an approach to calculate geostatistical operators for inverse problems on irregular meshes by eigendecomposition of a covariance matrix that contains the a priori geological information. Using our approach, the calculation of the operator matrix becomes tractable for 3-D inverse problems on irregular meshes. We tested the performance of the geostatistical regularization operators and compared them against the results of anisotropic smoothing in inversions of 2-D surface synthetic electrical resistivity tomography (ERT) data as well as in the inversion of a realistic 3-D cross-well synthetic ERT scenario. The inversions of 2-D ERT and seismic traveltime field data with geostatistical regularization provide results that are in good accordance with the expected geology and thus facilitate their interpretation. In particular, for layered structures the geostatistical regularization provides geologically more plausible results compared to the anisotropic smoothness constraints.

Factors associated with an increased risk of vertebral fracture in monoclonal gammopathies of undetermined significance

International Nuclear Information System (INIS)

Piot, J M; Royer, M; Schmidt-Tanguy, A; Hoppé, E; Gardembas, M; Bourrée, T; Hunault, M; François, S; Boyer, F; Ifrah, N; Renier, G; Chevailler, A; Audran, M; Chappard, D; Libouban, H; Mabilleau, G; Legrand, E; Bouvard, B

2015-01-01

Monoclonal gammopathies of undetermined significance (MGUS) have been shown to be associated with an increased risk of fractures. This study describes prospectively the bone status of MGUS patients and determines the factors associated with vertebral fracture. We included prospectively 201 patients with MGUS, incidentally discovered, and with no known history of osteoporosis: mean age 66.6±12.5 years, 48.3% women, 51.7% immunoglobulin G (IgG), 33.3% IgM and 10.4% IgA. Light chain was kappa in 64.2% patients. All patients had spinal radiographs and bone mineral density measurement in addition to gammopathy assessment. At least one prevalent non-traumatic vertebral fracture was discovered in 18.4% patients and equally distributed between men and women. Fractured patients were older, had a lower bone density and had also more frequently a lambda light chain isotype. Compared with patients with κ light chain, the odds ratio of being fractured for patients with λ light chain was 4.32 (95% confidence interval 1.80–11.16; P=0.002). These results suggest a high prevalence of non-traumatic vertebral fractures in MGUS associated with lambda light chain isotype and not only explained by low bone density

Chromosomal inversion differences correlate with range overlap in passerine birds.

Science.gov (United States)

Hooper, Daniel M; Price, Trevor D

2017-10-01

Chromosomal inversions evolve frequently but the reasons for this remain unclear. We used cytological descriptions of 411 species of passerine birds to identify large pericentric inversion differences between species, based on the position of the centromere. Within 81 small clades comprising 284 of the species, we found 319 differences on the 9 largest autosomes combined, 56 on the Z chromosome, and 55 on the W chromosome. We also identified inversions present within 32 species. Using a new fossil-calibrated phylogeny, we examined the phylogenetic, demographic and genomic context in which these inversions have evolved. The number of inversion differences between closely related species is consistently predicted by whether the ranges of species overlap, even when time is controlled for as far as is possible. Fixation rates vary across the autosomes, but inversions are more likely to be fixed on the Z chromosome than the average autosome. Variable mutagenic input alone (estimated by chromosome size, map length, GC content or repeat density) cannot explain the differences between chromosomes in the number of inversions fixed. Together, these results support a model in which inversions increase because of their effects on recombination suppression in the face of hybridization. Other factors associated with hybridization may also contribute, including the possibility that inversions contain incompatibility alleles, making taxa less likely to collapse following secondary contact.

Socioeconomic status is inversely associated with esophageal squamous cell carcinoma risk: results from a population-based case-control study in China

Science.gov (United States)

Suo, Chen; Yuan, Ziyu; Cheng, Hongwei; Zhang, Yuechan; Jin, Li; Lu, Ming; Chen, Xingdong; Ye, Weimin

2018-01-01

Socioeconomic status (SES) is suspected to influence the risk of esophageal squamous-cell carcinoma (ESCC) in China, however, the evidence is still inconclusive and the selection of SES indicators remains inconsistent. In current study, we examined the association between SES and risk of ESCC based on a population-based case-control study in Taixing, China, with 1298 histopathology-confirmed cases and 1900 controls recruited between October 2010 and September 2013. Data on SES indicators was collected using a structured questionnaire. We constructed a composite wealth score based on the ownership of a series of household appliances and other variables by using multiple correspondence analysis (MCA). We used unconditional logistic regression to estimate odds ratios (ORs) with 95% confidence intervals (CIs) of ESCC in association with SES indicators. SES was inversely associated with ESCC risk in current study. Higher education (secondary high school or above vs illiteracy, OR=0.60, 95%CI, 0.41-0.87), larger house area per person (>70 vs 5 years also had a lower ESCC risk. Whereas physical labor (very active vs sedentary, OR=1.69, 95%CI, 1.27-2.26) and larger families (≥6 vs <3 in household, OR=1.63, 95%CI, 1.30-2.03) increased the risk of ESCC. These findings confirm the strong inverse association between SES and ESCC risk. Future studies are needed to verify these findings and identify contributing factors underlying the observed associations. PMID:29467939

Type 1 IGF Receptor Localization in Paediatric Gliomas: Significant Association with WHO Grading and Clinical Outcome.

Science.gov (United States)

Clément, Florencia; Martin, Ayelen; Venara, Marcela; de Luján Calcagno, Maria; Mathó, Cecilia; Maglio, Silvana; Lombardi, Mercedes García; Bergadá, Ignacio; Pennisi, Patricia A

2018-06-01

Nuclear localization of insulin-like growth factor receptor type 1 (IGF-1R) has been described as adverse prognostic factor in some cancers. We studied the expression and localization of IGF-1R in paediatric patients with gliomas, as well as its association with World Health Organization (WHO) grading and survival. We conducted a single cohort, prospective study of paediatric patients with gliomas. Samples were taken at the time of the initial surgery; IGF-1R expression and localization were characterized by immunohistochemistry (IHC), subcellular fractionation and western blotting. Tumours (47/53) showed positive staining for IGF-1R by IHC. IGF-1R nuclear labelling was observed in 10/47 cases. IGF-1R staining was mostly non-nuclear in low-grade tumours, while IGF-1R nuclear labelling was predominant in high-grade gliomas (p = 0.0001). Survival was significantly longer in patients with gliomas having non-nuclear IGF-1R localization than in patients with nuclear IGF-1R tumours (p = 0.016). In gliomas, IGF-1R nuclear localization was significantly associated with both high-grade tumours and increased risk of death. Based on a prospective design, we provide evidence of a potential usefulness of intracellular localization of IGF-1R as prognostic factor in paediatric patients with gliomas.

Polymorphisms in the Tlr4 and Tlr5 Gene Are Significantly Associated with Inflammatory Bowel Disease in German Shepherd Dogs

Science.gov (United States)

Kathrani, Aarti; House, Arthur; Catchpole, Brian; Murphy, Angela; German, Alex; Werling, Dirk; Allenspach, Karin