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Achromatic, planar Fresnel-reflector for a single-beam magneto-optical trap. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2024; 95:013202. [PMID: 38270499 DOI: 10.1063/5.0174674] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Accepted: 12/19/2023] [Indexed: 01/26/2024]
Abstract
We present a novel achromatic, planar, periodic mirror structure for single-beam magneto-optical trapping and demonstrate its use in the first- and second-stage cooling and trapping for different isotopes of strontium. We refer to it as a Fresnel magneto-optical trap (MOT) as the structure is inspired by Fresnel lenses. By design, it avoids many of the problems that arise for multi-color cooling using planar structures based on diffraction gratings, which have been the dominant planar structures to be used for single-beam trapping thus far. In addition to a complex design process and cost-intensive fabrication, diffraction gratings suffer from their inherent chromaticity, which causes different axial displacements of trap volumes for different wavelengths and necessitates trade-offs in their diffraction properties and achievable trap depths. In contrast, the Fresnel-reflector structure presented here is a versatile, easy-to-manufacture device that combines achromatic beam steering with the advantages of a planar architecture. It enables miniaturizing trapping systems for alkaline-earth-like atoms with multiple cooling transitions as well as multi-species trapping in the ideal tetrahedral configuration and within the same volume above the structure. Our design presents a novel approach for the miniaturization of cold-atom systems based on single-beam MOTs and enables the widespread adoption of these systems.
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Cantharidin increases the force of contraction and protein phosphorylation in isolated human atria. NAUNYN-SCHMIEDEBERG'S ARCHIVES OF PHARMACOLOGY 2023; 396:2613-2625. [PMID: 37097333 PMCID: PMC10497697 DOI: 10.1007/s00210-023-02483-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Accepted: 03/30/2023] [Indexed: 04/26/2023]
Abstract
Cantharidin, an inhibitor of protein phosphatase 1 (PP1) and protein phosphatase 2A (PP2A), is known to increase the force of contraction and shorten the time to relaxation in human ventricular preparations. We hypothesized that cantharidin has similar positive inotropic effects in human right atrial appendage (RAA) preparations. RAA were obtained during bypass surgery performed on human patients. These trabeculae were mounted in organ baths and electrically stimulated at 1 Hz. For comparison, we studied isolated electrically stimulated left atrial (LA) preparations and isolated spontaneously beating right atrial (RA) preparations from wild-type mice. Cumulatively applied (starting at 10 to 30 µM), cantharidin exerted a positive concentration-dependent inotropic effect that plateaued at 300 µM in the RAA, LA, and RA preparations. This positive inotropic effect was accompanied by a shortening of the time to relaxation in human atrial preparations (HAPs). Notably, cantharidin did not alter the beating rate in the RA preparations. Furthermore, cantharidin (100 µM) increased the phosphorylation state of phospholamban and the inhibitory subunit of troponin I in RAA preparations, which may account for the faster relaxation observed. The generated data indicate that PP1 and/or PP2A play a functional role in human atrial contractility.
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Comparing ultrastable lasers at 7 × 10 -17 fractional frequency instability through a 2220 km optical fibre network. Nat Commun 2022; 13:212. [PMID: 35017500 PMCID: PMC8752831 DOI: 10.1038/s41467-021-27884-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Accepted: 12/14/2021] [Indexed: 11/24/2022] Open
Abstract
Ultrastable lasers are essential tools in optical frequency metrology enabling unprecedented measurement precision that impacts on fields such as atomic timekeeping, tests of fundamental physics, and geodesy. To characterise an ultrastable laser it needs to be compared with a laser of similar performance, but a suitable system may not be available locally. Here, we report a comparison of two geographically separated lasers, over the longest ever reported metrological optical fibre link network, measuring 2220 km in length, at a state-of-the-art fractional-frequency instability of 7 × 10-17 for averaging times between 30 s and 200 s. The measurements also allow the short-term instability of the complete optical fibre link network to be directly observed without using a loop-back fibre. Based on the characterisation of the noise in the lasers and optical fibre link network over different timescales, we investigate the potential for disseminating ultrastable light to improve the performance of remote optical clocks.
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Improved Constraints on Primordial Gravitational Waves using Planck, WMAP, and BICEP/Keck Observations through the 2018 Observing Season. PHYSICAL REVIEW LETTERS 2021; 127:151301. [PMID: 34678017 DOI: 10.1103/physrevlett.127.151301] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Accepted: 08/12/2021] [Indexed: 06/13/2023]
Abstract
We present results from an analysis of all data taken by the BICEP2, Keck Array, and BICEP3 CMB polarization experiments up to and including the 2018 observing season. We add additional Keck Array observations at 220 GHz and BICEP3 observations at 95 GHz to the previous 95/150/220 GHz dataset. The Q/U maps now reach depths of 2.8, 2.8, and 8.8 μK_{CMB} arcmin at 95, 150, and 220 GHz, respectively, over an effective area of ≈600 square degrees at 95 GHz and ≈400 square degrees at 150 and 220 GHz. The 220 GHz maps now achieve a signal-to-noise ratio on polarized dust emission exceeding that of Planck at 353 GHz. We take auto- and cross-spectra between these maps and publicly available WMAP and Planck maps at frequencies from 23 to 353 GHz and evaluate the joint likelihood of the spectra versus a multicomponent model of lensed ΛCDM+r+dust+synchrotron+noise. The foreground model has seven parameters, and no longer requires a prior on the frequency spectral index of the dust emission taken from measurements on other regions of the sky. This model is an adequate description of the data at the current noise levels. The likelihood analysis yields the constraint r_{0.05}<0.036 at 95% confidence. Running maximum likelihood search on simulations we obtain unbiased results and find that σ(r)=0.009. These are the strongest constraints to date on primordial gravitational waves.
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Abstract
Background Texture-related factors such as consistency, vascularity, and adherence vary considerably in meningioma and are thought to be linked with surgical resectability and morbidity. However, data analyzing the true impact of meningioma texture on the surgical management is sparse. Methods Patients with intracranial meningioma treated between 08/2014 and 04/2018 at our institution were prospectively collected for demographics, clinical presentation, histology, and surgical treatment with related morbidity and extend of resection. Tumor characteristics were reported by the surgeon using a standardized questionnaire including items such as tumor consistency, homogeneity, vascularization, and adherence to surrounding neurovascular structure and analyzed for their impact surgical outcome parameters using univariate and logistic regression analyses. Results Tumor texture-related parameters of 300 patients (72.3% female) with meningioma were analyzed. Meningioma localizations were grouped into 3 different cohorts namely convexity, skull base, and posterior. Postoperative occurrence of a neurological deficit (transient 23.0%; permanent 6.1%) was associated with the duration of surgery (P = .001), size of tumor (P = .046), tumor vascularization (P = .015), and adherence to neurovascular structures (P = .002). Coherently, the duration of surgery (mean 230.99 ± 101.33 min) was associated with size of tumor (P < .0001), vascularization (P < .0001), and adherence (P < .0001). Similar associations were recapitulated in subgroup analyses of different tumor localizations. Noteworthy, tumor rigidity had no significant impact on time of surgery and neurological outcome. Conclusions Our analysis demonstrates that tumor texture has an impact on the surgical management of meningioma and provides data that tumor vascularization and adherence are significant factors influencing surgical outcome whereas the influence of tumor consistency has less impact than previously thought.
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MNGI-02. FEATURES OF TUMOR TEXTURE INFLUENCE SURGERY AND OUTCOME IN INTRACRANIAL MENINGIOMA. Neuro Oncol 2019. [DOI: 10.1093/neuonc/noz175.584] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
OBJECTIVE
Texture-related factors such as consistency, vascularity and adherence vary considerably in meningioma and are thought to be linked with surgical resectability and morbidity. However, data analyzing the true impact of meningioma texture on the surgical management is sparse.
METHODS
Patients with intracranial meningioma treated between 08/2014-04/2018 were prospectively collected for demographics and surgical treatment with related morbidity and extend of resection (EOR). Tumor characteristics were reported by the surgeon using a standardized questionnaire including items such as tumor rigidity, homogeneity, vascularization and adherence to surrounding neurovascular structure and analyzed for their impact on EOR and neurological outcome using multivariate regression analyses.
RESULTS
296 patients (214 female (72.3%) with intracranial meningiomas were included with a mean age of 60.4 years. 23% of patients had a transient and 6.1% permanent neurological deficits and three patients (1.1%) died. The occurrence of a neurological deficit was associated with duration of surgery (p = 0.013) and tumor adherence to neurovascular structures (p = 0.014). Similar associations were observed in subgroup analyses of different tumor localizations (e.g. convexity and skull base). With regard to EOR, the tumor adherence (p < 0.001) and recurrent surgery (p = 0.001) were found as independent predictors for subtotal resection. Noteworthy, the tumor rigidity had no significant impact on the morbidity or EOR.
CONCLUSION
Our analysis supports the notion that tumor texture has an impact on the surgical management of meningioma and provides sound data that tumor adherence is a significant factor influencing neurological outcome and EOR. In contrast, the influence of tumor rigidity has less impact than previously thought. Preoperative prediction of tumor texture is therefore required for optimized risk assessment.
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Abstract
BACKGROUND Children and adolescents with severe hemophilia commonly suffer from acute and chronic pain as a consequence of hemophilia-related bleeding. Intervention-related pain also plays a major role. Despite its high prevalence in this patient group, hemophilia-related pain is not always adequately addressed and sufficiently treated. OBJECTIVES This paper discusses how to improve pain management for children and adolescents (0-18 years) with hemophilia and which specific features in this population should influence decisions in pain management. MATERIALS AND METHODS An expert panel discussed challenges in pain treatment in children and adolescents with hemophilia. Recommendations are based on evidence and clinical experience. RESULT Pain management in children with hemophilia needs improvement. Children with hemophilia are at risk of developing chronic pain and of suffering traumatization due to insufficient pain management. Pain therapy can be challenging in these children as both their age and the underlying disease limit the options in particular in pain medication. The expert panel developed recommendations to improve pain management in children with hemophilia.
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Constraints on Primordial Gravitational Waves Using Planck, WMAP, and New BICEP2/Keck Observations through the 2015 Season. PHYSICAL REVIEW LETTERS 2018; 121:221301. [PMID: 30547645 DOI: 10.1103/physrevlett.121.221301] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Revised: 08/28/2018] [Indexed: 06/09/2023]
Abstract
We present results from an analysis of all data taken by the bicep2/Keck CMB polarization experiments up to and including the 2015 observing season. This includes the first Keck Array observations at 220 GHz and additional observations at 95 and 150 GHz. The Q and U maps reach depths of 5.2, 2.9, and 26 μK_{CMB} arcmin at 95, 150, and 220 GHz, respectively, over an effective area of ≈400 square degrees. The 220 GHz maps achieve a signal to noise on polarized dust emission approximately equal to that of Planck at 353 GHz. We take auto and cross spectra between these maps and publicly available WMAP and Planck maps at frequencies from 23 to 353 GHz. We evaluate the joint likelihood of the spectra versus a multicomponent model of lensed-ΛCDM+r+dust+synchrotron+noise. The foreground model has seven parameters, and we impose priors on some of these using external information from Planck and WMAP derived from larger regions of sky. The model is shown to be an adequate description of the data at the current noise levels. The likelihood analysis yields the constraint r_{0.05}<0.07 at 95% confidence, which tightens to r_{0.05}<0.06 in conjunction with Planck temperature measurements and other data. The lensing signal is detected at 8.8σ significance. Running a maximum likelihood search on simulations we obtain unbiased results and find that σ(r)=0.020. These are the strongest constraints to date on primordial gravitational waves.
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EP-2011: Accuracy of NTCP models for rectum and bladder toxicity in prostate cancer patients. Radiother Oncol 2018. [DOI: 10.1016/s0167-8140(18)32320-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Abstract
BACKGROUND Resistance of uropathogenic bacteria against the common antibiotics is considerable-especially in the elderly. OBJECTIVES In Germany nitroxoline is licensed for the treatment of acute urinary tract infections and for prophylaxis of recurrent infections. What is the actual resistance pattern of uropathogenic bacteria? MATERIALS AND METHODS The in vitro susceptibility of 477 uropathogenic bacteria from patients in 2015 was determined by means of the agar diffusion method. RESULTS Obviously, this agent is still active against the vast majority of uropathogenic bacteria and in particular against strains of Escherichia coli (E. coli). Pseudomonas aeruginosa and enterococci are not really within the spectrum of nitroxoline. One has to keep in mind, however, that even among E. coli and other enterobacteriaceae there are single resistant isolates. This applies in particular to problem strains resistant to many other antibiotics. DISCUSSION Nitroxoline is a reasonable alternative and a promising option for calculated treatment of urinary tract infections-especially of the elderly, although this drug is not recommended in the current guideline. Laboratory testing of clinical isolates should be requested-at least when treatment fails.
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Whole-body vibration training as a workplace-based sports activity for employees with chronic low-back pain. Scand J Med Sci Sports 2017; 27:2027-2039. [PMID: 28185300 DOI: 10.1111/sms.12852] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/06/2017] [Indexed: 11/26/2022]
Abstract
The goal of this randomized and controlled study was to examine whether whole-body vibration (WBV) training is able to reduce back pain and physical disability in seated working office employees with chronic low-back pain in a real-world setting. A total of 41 subjects (68.3% female/mean age 45.5±9.1 years/mean BMI 26.6±5.2) were randomly allocated to an intervention group (INT [n=21]) or a control group (CON [n=20]). The INT participated in WBV training 2.5 times per week for 3 months. The primary outcome was the change in the Roland and Morris disability questionnaire (RMQ) score over the study period. In addition, secondary outcomes included changes in the Oswestry Disability Index (ODI), the Work Ability Index Questionnaire, the quality of life questionnaire SF-36, the Freiburger activity questionnaire, and an isokinetic test of the musculature of the trunk. Compliance with the intervention in the INT reached a mean of 81.1%±31.2% with no long-lasting unwanted side effects. We found significant positive effects of 3 months of WBV training in the INT compared to the CON regarding the RMQ (P=.027), the ODI (P=.002), the SF-36 (P=.013), the Freiburger activity questionnaire (P=.022), the post-interventional sick-leave in the INT (P=.008), and trends regarding a positive effect of the intervention on the muscular capacity of the muscles of the trunk in flexion. WBV training seems to be an effective, safe, and suitable intervention for seated working employees with chronic low-back pain.
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Improved Constraints on Cosmology and Foregrounds from BICEP2 and Keck Array Cosmic Microwave Background Data with Inclusion of 95 GHz Band. PHYSICAL REVIEW LETTERS 2016; 116:031302. [PMID: 26849583 DOI: 10.1103/physrevlett.116.031302] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2015] [Indexed: 06/05/2023]
Abstract
We present results from an analysis of all data taken by the BICEP2 and Keck Array cosmic microwave background (CMB) polarization experiments up to and including the 2014 observing season. This includes the first Keck Array observations at 95 GHz. The maps reach a depth of 50 nK deg in Stokes Q and U in the 150 GHz band and 127 nK deg in the 95 GHz band. We take auto- and cross-spectra between these maps and publicly available maps from WMAP and Planck at frequencies from 23 to 353 GHz. An excess over lensed ΛCDM is detected at modest significance in the 95×150 BB spectrum, and is consistent with the dust contribution expected from our previous work. No significant evidence for synchrotron emission is found in spectra such as 23×95, or for correlation between the dust and synchrotron sky patterns in spectra such as 23×353. We take the likelihood of all the spectra for a multicomponent model including lensed ΛCDM, dust, synchrotron, and a possible contribution from inflationary gravitational waves (as parametrized by the tensor-to-scalar ratio r) using priors on the frequency spectral behaviors of dust and synchrotron emission from previous analyses of WMAP and Planck data in other regions of the sky. This analysis yields an upper limit r_{0.05}<0.09 at 95% confidence, which is robust to variations explored in analysis and priors. Combining these B-mode results with the (more model-dependent) constraints from Planck analysis of CMB temperature plus baryon acoustic oscillations and other data yields a combined limit r_{0.05}<0.07 at 95% confidence. These are the strongest constraints to date on inflationary gravitational waves.
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Antibiotikaverbrauch bei Kindern mit akuten Atemwegs- oder Ohrinfekten: eine prospektive Beobachtungsstudie zum Vergleich zwischen anthroposophischer und konventioneller Behandlung in der hausärztlichen Routineversorgung. ACTA ACUST UNITED AC 2016. [DOI: 10.14271/dms-20637-de] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Long-Term Respiratory Support for Children and Adolescents in Austria: A National Survey. KLINISCHE PADIATRIE 2015; 228:42-6. [PMID: 26697738 DOI: 10.1055/s-0035-1565240] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
BACKGROUND Population-based data on pediatric patients on long-term respiratory support (LTRS) in Austria are lacking. This study aimed to record the pediatric departments active in this field, as well as number and characteristics of patients on LTRS. METHODS A national cross-sectional study was carried out by means of questionnaires sent to all pediatric departments in Austria. RESULTS All departments answered to the questionnaires. On June 1st, 2013, the reference day for this study, 12 of the 41 pediatric departments in Austria were active in the field. At this time, these centers were caring for 143 patients, 111 (77.6%) of them under 18 years, which corresponds to a prevalence of 7.4 per 100 000. The patients suffered from neuromuscular disorders (44%), other neurological disorders (18.9%), disorders of respiratory drive (9.1%), obstructive sleep apnea (8.4%), thoracal and spinal diseases (8.4%), pulmonary disorders (4.9%) and other diseases (6.3%). Continuous positive airway pressure was used in 6.3%, non-invasive ventilation in 60.1% and invasive ventilation in 33.6% of the patients, respectively. LTRS was performed at home in 92.3%. CONCLUSION LTRS represents a common management strategy in children and adolescents with a variety of disorders. Census reports such as this one provide the basis for appropriate planning of resource allocation. The age distribution of our patients shows the need for structured transition into adult care.
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BICEP2/KECK ARRAY V: MEASUREMENTS OFB-MODE POLARIZATION AT DEGREE ANGULAR SCALES AND 150 GHz BY THE KECK ARRAY. ACTA ACUST UNITED AC 2015. [DOI: 10.1088/0004-637x/811/2/126] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Lithium-induced Clock Gene Expression in Lymphoblastoid Cells of Bipolar Affective Patients. PHARMACOPSYCHIATRY 2015; 48:145-9. [PMID: 26011568 DOI: 10.1055/s-0035-1549946] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
INTRODUCTION Disturbances of circadian rhythms occur in all episodes of bipolar disorder (BD). Lithium, as gold-standard in the maintenance treatment of BD, is known to influence circadian processes. METHODS In a pilot study lymphoblastoid cell lines (LCLs) were generated from 8 BD patients and 6 healthy controls. The LCLs were treated with lithiumchloride (LiCl) for 3 weeks. Cell cycles were then synchronized and expressional analysis by quantitative Real Time PCR was done. RESULTS BD and controls differed in the period length regarding DBP (albumin D-box binding protein) expression and DBP expression was also influenced by lithium treatment. Furthermore, baseline DBP expression was significantly different between non-treated BD and healthy controls. None of the other analyzed circadian genes showed to be influenced by chronic lithium treatment or to be differentially regulated due to the diagnosis. DISCUSSION We here show that chronic lithium treatment of LCLs leads to decreased expression of the clock gene DBP, rendering DBP a lithium-regulated gene. We could confirm the role of the circadian clock as well in lithium mode of action as in the pathomechanisms of BD although future studies with a greater number of participants and cell lines are needed.
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The skin of domestic mammals as a model for the human skin, with special reference to the domestic pig. CURRENT PROBLEMS IN DERMATOLOGY 2015; 7:39-52. [PMID: 752456 DOI: 10.1159/000401274] [Citation(s) in RCA: 287] [Impact Index Per Article: 31.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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PO-0893: Robustness of biologically-based treatment planning for prostate cancer patients. Radiother Oncol 2015. [DOI: 10.1016/s0167-8140(15)40885-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Joint analysis of BICEP2/keck array and Planck Data. PHYSICAL REVIEW LETTERS 2015; 114:101301. [PMID: 25815919 DOI: 10.1103/physrevlett.114.101301] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2015] [Indexed: 06/04/2023]
Abstract
We report the results of a joint analysis of data from BICEP2/Keck Array and Planck. BICEP2 and Keck Array have observed the same approximately 400 deg^{2} patch of sky centered on RA 0 h, Dec. -57.5°. The combined maps reach a depth of 57 nK deg in Stokes Q and U in a band centered at 150 GHz. Planck has observed the full sky in polarization at seven frequencies from 30 to 353 GHz, but much less deeply in any given region (1.2 μK deg in Q and U at 143 GHz). We detect 150×353 cross-correlation in B modes at high significance. We fit the single- and cross-frequency power spectra at frequencies ≥150 GHz to a lensed-ΛCDM model that includes dust and a possible contribution from inflationary gravitational waves (as parametrized by the tensor-to-scalar ratio r), using a prior on the frequency spectral behavior of polarized dust emission from previous Planck analysis of other regions of the sky. We find strong evidence for dust and no statistically significant evidence for tensor modes. We probe various model variations and extensions, including adding a synchrotron component in combination with lower frequency data, and find that these make little difference to the r constraint. Finally, we present an alternative analysis which is similar to a map-based cleaning of the dust contribution, and show that this gives similar constraints. The final result is expressed as a likelihood curve for r, and yields an upper limit r_{0.05}<0.12 at 95% confidence. Marginalizing over dust and r, lensing B modes are detected at 7.0σ significance.
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Abstract
BACKGROUND Four international study groups undertook a large study in resectable osteosarcoma, which included two randomised controlled trials, to determine the effect on survival of changing post-operative chemotherapy based on histological response. PATIENTS AND METHODS Patients with resectable osteosarcoma aged ≤40 years were treated with the MAP regimen, comprising pre-operatively of two 5-week cycles of cisplatin 120 mg/m(2), doxorubicin 75 mg/m(2), methotrexate 12 g/m(2) × 2 (MAP) and post-operatively two further cycles of MAP and two cycles of just MA. Patients were randomised after surgery. Those with ≥10% viable tumour in the resected specimen received MAP or MAP with ifosfamide and etoposide. Those with <10% viable tumour were allocated to MAP or MAP followed by pegylated interferon. Longitudinal evaluation of quality of life was undertaken. RESULTS Recruitment was completed to the largest osteosarcoma study to date in 75 months. Commencing March 2005, 2260 patients were registered from 326 centres across 17 countries. About 1334 of 2260 registered patients (59%) were randomised. Pre-operative chemotherapy was completed according to protocol in 94%. Grade 3-4 neutropenia affected 83% of cycles and 59% were complicated by infection. There were three (0.13%) deaths related to pre-operative chemotherapy. At definitive surgery, 50% of patients had at least 90% necrosis in the resected specimen. CONCLUSIONS New models of collaboration are required to successfully conduct trials to improve outcomes of patients with rare cancers; EURAMOS-1 demonstrates achievability. Considerable regulatory, financial and operational challenges must be overcome to develop similar studies in the future. The trial is registered as NCT00134030 and ISRCTN 67613327.
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Toxicity and Efficacy Results From a Phase I Dose-Escalation Study of Single-Fraction Stereotactic Radiation Therapy for Liver Metastases. Int J Radiat Oncol Biol Phys 2014. [DOI: 10.1016/j.ijrobp.2014.05.186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Detection of B-mode polarization at degree angular scales by BICEP2. PHYSICAL REVIEW LETTERS 2014; 112:241101. [PMID: 24996078 DOI: 10.1103/physrevlett.112.241101] [Citation(s) in RCA: 98] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2014] [Indexed: 06/03/2023]
Abstract
We report results from the BICEP2 experiment, a cosmic microwave background (CMB) polarimeter specifically designed to search for the signal of inflationary gravitational waves in the B-mode power spectrum around ℓ∼80. The telescope comprised a 26 cm aperture all-cold refracting optical system equipped with a focal plane of 512 antenna coupled transition edge sensor 150 GHz bolometers each with temperature sensitivity of ≈300 μK(CMB)√s. BICEP2 observed from the South Pole for three seasons from 2010 to 2012. A low-foreground region of sky with an effective area of 380 square deg was observed to a depth of 87 nK deg in Stokes Q and U. In this paper we describe the observations, data reduction, maps, simulations, and results. We find an excess of B-mode power over the base lensed-ΛCDM expectation in the range 30 < ℓ < 150, inconsistent with the null hypothesis at a significance of >5σ. Through jackknife tests and simulations based on detailed calibration measurements we show that systematic contamination is much smaller than the observed excess. Cross correlating against WMAP 23 GHz maps we find that Galactic synchrotron makes a negligible contribution to the observed signal. We also examine a number of available models of polarized dust emission and find that at their default parameter values they predict power ∼(5-10)× smaller than the observed excess signal (with no significant cross-correlation with our maps). However, these models are not sufficiently constrained by external public data to exclude the possibility of dust emission bright enough to explain the entire excess signal. Cross correlating BICEP2 against 100 GHz maps from the BICEP1 experiment, the excess signal is confirmed with 3σ significance and its spectral index is found to be consistent with that of the CMB, disfavoring dust at 1.7σ. The observed B-mode power spectrum is well fit by a lensed-ΛCDM+tensor theoretical model with tensor-to-scalar ratio r = 0.20_(-0.05)(+0.07), with r = 0 disfavored at 7.0σ. Accounting for the contribution of foreground, dust will shift this value downward by an amount which will be better constrained with upcoming data sets.
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Abstract
We report on the first experiments with Fourier Transform technique in K-band. Due to the limited performance of some components frequencies up to 20.5 GHz only could be reached. Some T2-relaxation measurements are given.
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Quadrupole Coupling in Benzonitrile. An Application of Microwave Fourier Transform Spectroscopy. ACTA ACUST UNITED AC 2014. [DOI: 10.1515/zna-1981-1021] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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A Microwave Fourier Transform Spectrometer in the Range from 18 to 26.4 GHz Increased Sensitivity Using Circular Waveguides. Measurements of Isotopomeres of Carbonylsulfide and of Methane. ACTA ACUST UNITED AC 2014. [DOI: 10.1515/zna-1991-0511] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
We present a microwave Fourier transform spectrometer in the region of 18 to 26.4 GHz with an increase in sensitivity roughly by a factor of ten in comparison to a former set up. Measurements of rotational transitions of isotopomers of carbonylsulfide, OCS, in natural abundance and of rovibrational transitions of methane, CH4, illustrate the improvement
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Focused shape models for hip joint segmentation in 3D magnetic resonance images. Med Image Anal 2014; 18:567-78. [DOI: 10.1016/j.media.2014.02.002] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2013] [Revised: 01/29/2014] [Accepted: 02/05/2014] [Indexed: 01/18/2023]
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Photophysics of single crystal [Pt(o-phen) (CN)2]: Optical properties at external magnetic fields and at high pressures. ACTA ACUST UNITED AC 2014. [DOI: 10.1002/bbpc.19870911129] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Automatic model-based semantic registration of multimodal MRI knee data. J Magn Reson Imaging 2014; 41:633-44. [PMID: 24591252 DOI: 10.1002/jmri.24609] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2013] [Accepted: 02/11/2014] [Indexed: 11/11/2022] Open
Abstract
PURPOSE To propose a robust and automated model-based semantic registration for the multimodal alignment of the knee bone and cartilage from three-dimensional (3D) MR image data. MATERIALS AND METHODS The movement of the knee joint can be semantically interpreted as a combination of movements of each bone. A semantic registration of the knee joint was implemented by separately reconstructing the rigid movements of the three bones. The proposed method was validated by registering 3D morphological MR datasets of 25 subjects into the corresponding T2 map datasets, and was compared with rigid and elastic methods using two criteria: the spatial overlap of the manually segmented cartilage and the distance between the same landmarks in the reference and target datasets. RESULTS The mean Dice Similarity Coefficient (DSC) of the overlapped cartilage segmentation was increased to 0.68 ± 0.1 (mean ± SD) and the landmark distance was reduced to 1.3 ± 0.3 mm after the proposed registration method. Both metrics were statistically superior to using rigid (DSC: 0.59 ± 0.12; landmark distance: 2.1 ± 0.4 mm) and elastic (DSC: 0.64 ± 0.11; landmark distance: 1.5 ± 0.5 mm) registrations. CONCLUSION The proposed method is an efficient and robust approach for the automated registration between morphological knee datasets and T2 MRI relaxation maps.
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Healthcare worker-related MRSA cluster in a German neonatology level III ICU: A true European story. Int J Hyg Environ Health 2014; 217:307-11. [DOI: 10.1016/j.ijheh.2013.07.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2013] [Revised: 07/01/2013] [Accepted: 07/02/2013] [Indexed: 11/29/2022]
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Automatic detection of anatomical landmarks on the knee joint using MRI data. J Magn Reson Imaging 2014; 41:183-92. [DOI: 10.1002/jmri.24516] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2013] [Accepted: 10/23/2013] [Indexed: 11/08/2022] Open
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Evaluation of Six PCR Assays in Combination with Patient Related Data for the Diagnosis of Clostridium difficile-Associated Infections. Clin Lab 2014; 60:1343-50. [PMID: 25185420 DOI: 10.7754/clin.lab.2013.130735] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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[Serious sepsis treatment in intensive care departments in the Czech Republic - EPOSS Project pilot results]. VNITRNI LEKARSTVI 2013; 59:962-970. [PMID: 24279439] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
INTRODUCTION Severe sepsis is still associated with significant morbidity and mortality, which is however different, as well as its management, depending on the region. What is the situation in the Czech Republic and what is the character of patients with severe sepsis is currently not known. The aim of the project is to describe the processes of care, outcome and characteristics of patients with severe sepsis admitted to the intensive care department of the Czech Republic. METHODS This is a multicentre and observational project with retrospective enrollment of patients who meet the criteria for severe sepsis before or within 24 hours after admission to selected intensive care units (ICU EPOSS). RESULTS 394 patients were analyzed. Median age at admission was 66 (56- 76) years, males predominated (58.9%) and the median APACHE II score on admission was 25 (19- 32). Patients were predominantly medical (56.9%) and most were secondary admitted from other ICU (53.6%). Meeting the criteria of severe sepsis was most frequently within the period (± 4 hours) of admission the EPOSS ICU (77.6%). Median total fluid intake during the first 24 hours was 6,680 (4,840- 9,450) ml. Most patients required mechanical ventilation (58.4%). Compliance with the resuscitation bundle of severe sepsis in our group was very good and was associated with lower mortality of patients. Most frequently, the EPOSS ICU length of stay (LOS) was 7 (3- 15) days and median hospital LOS was 13 (8- 28) days. Hospital mortality in our cohort was 35.8%. CONCLUSION Introducing the project, which in its first stage obtained valuable and internationally comparable data about patients with severe sepsis admitted to the involved ICU in the Czech Republic.
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Automated bone segmentation from large field of view 3D MR images of the hip joint. Phys Med Biol 2013; 58:7375-90. [DOI: 10.1088/0031-9155/58/20/7375] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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Methylphenidate regulates HEY1, SLC2A3, ATXN1, GUCY1B3 and MAP3K8 in lymphoblastoid cells from adult ADHD patients. PHARMACOPSYCHIATRY 2013. [DOI: 10.1055/s-0033-1353318] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Three-dimensional morphological and signal intensity features for detection of intervertebral disc degeneration from magnetic resonance images. J Am Med Inform Assoc 2013; 20:1082-90. [PMID: 23813538 DOI: 10.1136/amiajnl-2012-001547] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
BACKGROUND AND OBJECTIVES Advances in MRI hardware and sequences are continually increasing the amount and complexity of data such as those generated in high-resolution three-dimensional (3D) scanning of the spine. Efficient informatics tools offer considerable opportunities for research and clinically based analyses of magnetic resonance studies. In this work, we present and validate a suite of informatics tools for automated detection of degenerative changes in lumbar intervertebral discs (IVD) from both 3D isotropic and routine two-dimensional (2D) clinical T2-weighted MRI. MATERIALS AND METHODS An automated segmentation approach was used to extract morphological (traditional 2D radiological measures and novel 3D shape descriptors) and signal appearance (extracted from signal intensity histograms) features. The features were validated against manual reference, compared between 2D and 3D MRI scans and used for quantification and classification of IVD degeneration across magnetic resonance datasets containing IVD with early and advanced stages of degeneration. RESULTS AND CONCLUSIONS Combination of the novel 3D-based shape and signal intensity features on 3D (area under receiver operating curve (AUC) 0.984) and 2D (AUC 0.988) magnetic resonance data deliver a significant improvement in automated classification of IVD degeneration, compared to the combination of previously used 2D radiological measurement and signal intensity features (AUC 0.976 and 0.983, respectively). Further work is required regarding the usefulness of 2D and 3D shape data in relation to clinical scores of lower back pain. The results reveal the potential of the proposed informatics system for computer-aided IVD diagnosis from MRI in large-scale research studies and as a possible adjunct for clinical diagnosis.
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Controversies in childhood osteosarcoma. Minerva Pediatr 2013; 65:125-148. [PMID: 23612259] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Osteosarcoma, the most frequent bone cancer of children and adolescents, will almost always result in death due to pulmonary metastatic disease unless treated by surgery and effective multidrug chemotherapy. Imaging of the primary tumor is by X-ray and magnetic resonance imaging. Imaging of the chest is by computed tomography, but many questions regarding the interpretation of small, nonspecific findings and how to deal with them remain. The diagnosis must be confirmed by a well-placed biopsy. Chemotherapy is usually initiated prior to definitive surgery. Treatment generally includes high-dose methotrexate, doxorubicin, and cisplatin, with some regimens also incorporating ifosfamide. While limb-saving resections have become standard after completion of skeletal growth, reconstruction in the growing child poses much greater challenges. The use of modern, expandable endoprostheses, but also rotation-plasties and even amputation may all be valid options in selected cases. Histologic response of the primary to preoperative chemotherapy has been identified as an important prognostic factor. Various imaging methods can help to predict tumor response to preoperative chemotherapy, yet all have their limitations. Results of a randomized trial assessing if modifying postoperative treatment based on the extent of response will improve results, EURAMOS-1, are pending. The debate about whether biologic agents or targeted therapies added to chemotherapy might improve outcomes is ongoing. Follow-up to detect late-effects of treatment and recurrences of osteosarcoma must be continued for several decades.
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Automated detection, 3D segmentation and analysis of high resolution spine MR images using statistical shape models. Phys Med Biol 2012. [PMID: 23201861 DOI: 10.1088/0031-9155/57/24/8357] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Recent advances in high resolution magnetic resonance (MR) imaging of the spine provide a basis for the automated assessment of intervertebral disc (IVD) and vertebral body (VB) anatomy. High resolution three-dimensional (3D) morphological information contained in these images may be useful for early detection and monitoring of common spine disorders, such as disc degeneration. This work proposes an automated approach to extract the 3D segmentations of lumbar and thoracic IVDs and VBs from MR images using statistical shape analysis and registration of grey level intensity profiles. The algorithm was validated on a dataset of volumetric scans of the thoracolumbar spine of asymptomatic volunteers obtained on a 3T scanner using the relatively new 3D T2-weighted SPACE pulse sequence. Manual segmentations and expert radiological findings of early signs of disc degeneration were used in the validation. There was good agreement between manual and automated segmentation of the IVD and VB volumes with the mean Dice scores of 0.89 ± 0.04 and 0.91 ± 0.02 and mean absolute surface distances of 0.55 ± 0.18 mm and 0.67 ± 0.17 mm respectively. The method compares favourably to existing 3D MR segmentation techniques for VBs. This is the first time IVDs have been automatically segmented from 3D volumetric scans and shape parameters obtained were used in preliminary analyses to accurately classify (100% sensitivity, 98.3% specificity) disc abnormalities associated with early degenerative changes.
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[Laboratory survey on the incidence of Pneumocystis jirovecii - obviously a peculiar fungus, but also a rare pathogen?]. Dtsch Med Wochenschr 2012; 137:2229-31. [PMID: 23076671 DOI: 10.1055/s-0032-1327231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Pneumocystsis jirovecii is a peculiar fungus for a variety of reasons. This opportunistic pathogen multiplies in humans only under certain conditions; a defect in the T-cell defense system creates a predisposition to this infection. In 2010 a data survey (IFT as well as PCR) from a few laboratories in Germany revealed 412 positive individuals. Even if only a few patients test positive for the colonization stage of this pathogen, the sheer number of individuals testing positive for other stages of infection indicate that the incidence of pneumocystosis in immunocompromised patients in Germany is underestimated.
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Secondary electron emission yield (SEY) in amorphous and graphitic carbon films prepared by PLD. ACTA ACUST UNITED AC 2012. [DOI: 10.1002/pssc.201100813] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Pathways to Earth-like atmospheres. Extreme ultraviolet (EUV)-powered escape of hydrogen-rich protoatmospheres. ORIGINS LIFE EVOL B 2011; 41:503-22. [PMID: 22314970 DOI: 10.1007/s11084-012-9264-7] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2011] [Accepted: 01/23/2012] [Indexed: 10/14/2022]
Abstract
We discuss the evolution of the atmosphere of early Earth and of terrestrial exoplanets which may be capable of sustaining liquid water oceans and continents where life may originate. The formation age of a terrestrial planet, its mass and size, as well as the lifetime in the EUV-saturated early phase of its host star play a significant role in its atmosphere evolution. We show that planets even in orbits within the habitable zone of their host stars might not lose nebular- or catastrophically outgassed initial protoatmospheres completely and could end up as water worlds with CO2 and hydrogen- or oxygen-rich upper atmospheres. If an atmosphere of a terrestrial planet evolves to an N2-rich atmosphere too early in its lifetime, the atmosphere may be lost. We show that the initial conditions set up by the formation of a terrestrial planet and by the evolution of the host star's EUV and plasma environment are very important factors owing to which a planet may evolve to a habitable world. Finally we present a method for studying the discussed atmosphere evolution hypotheses by future UV transit observations of terrestrial exoplanets.
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Substitute voice production: quantification of PE segment vibrations using a biomechanical model. IEEE Trans Biomed Eng 2011; 58:2767-76. [PMID: 21558056 DOI: 10.1109/tbme.2011.2151860] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
After total larynx excision due to laryngeal cancer, the tracheoesophageal substitute tissue vibrations at the intersection between the pharynx and the esophagus [pharyngoesophageal segment (PE segment)] serve as voice generator. The quality of the substitute voice significantly depends on the vibratory characteristics of the PE segment. For improving voice rehabilitation, the relationship between the PE dynamics and the resulting substitute voice quality is a matter of particular interest. Precondition for a comprehensive analysis of this relationship is an objective quantification of the PE vibrations. For quantification purposes, a method is proposed, which is based on the reproduction of the tissue vibrations by means of a biomechanical model of the PE segment. An optimization procedure for an automatic determination of appropriate model parameters is suggested to adapt the model dynamics to tissue movements extracted from high-speed (HS) videos. The applicability of the optimization procedure is evaluated with ten synthetic data sets. A mean error of 8.2% for the determination of previously defined model parameters was achieved as well as an overall stability of 7.1%. The application of the model to six HS recordings presented a mean correlation of the vibration patterns of 82%.
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Abstract
ABSTRACTCo on AlGaN is expected to form a large barrier Schottky contact due to its high work function. We have used this material combination with 18 % of Al in AlxGaN for the study of transient photoresponse in the photovoltaic mode and in secondary photocurrent measurements after pulsed laser excitation. In reverse bias and in short- circuit mode a fast decay with a characteristic time of a few microseconds is dominant at room temperature. This mode is appropriate for UV detector operation. At elevated temperature, a much slower tail extending to several milliseconds is also observed. In forward bias operation the slow tail is dominating at any temperature. We discuss this asymmetry with respect to fast minority carrier collection within the space charge region for primary photocurrents and the slower majority carrier transport in forward bias.
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Vergleichende Untersuchungen zur Struktur der Haarfollikelgruppen bei neuseeländischen Cashmere-, Angora- und Cashgoraziegen. J Anim Breed Genet 2011; 111:391-403. [DOI: 10.1111/j.1439-0388.1994.tb00476.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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48
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Molekulare Pathogenese der Nephronophthise: Nephrozystin 4 reguliert die Aktivität des Hippo-Signalweges. KLINISCHE PADIATRIE 2011. [DOI: 10.1055/s-0031-1273783] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Carrier Transport Through Grain Boundaries in Hydrogenated Microcrystalline Silicon. ACTA ACUST UNITED AC 2011. [DOI: 10.1557/proc-283-513] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
ABSTRACTTo analyse the influence of the grain boundaries (gb) on the transport of carriers in hydrogenated microcrystalline silicon (μC-Si:H) the ambipolar diffusion length (LLMB) was measured by SSPG. In addition, the films were characterised by photo-conductivity, dark conductivity activation energy, Urbach energy (determined by CPM), hydrogen effusion, Raman spectroscopy, X-ray scattering and optical transmission.The sample series was prepared by PECVD of SiH4 diluted with increasing H2 content. Taking the structural information by Raman spectra and X-ray into account, we explain our optical and activation energy measurements within a three-phase-model (amorphous phase, crystalline phase, gb) and a Fermi level pinning in μc-Si:H.
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Abstract
AbstractWe report the preparation of α-(Si.Ge):H alloy films by decomposition of SiF4, GeF4, and H2 in a d.c. glow discharge. Germanium is incorporated very efficiently from GeF4. The germanium content and optical gap canbe controlled by varying the GeF4 flow while keeping the SiF4 and H2 flows constant. The films, all prepared at 300 ºC substrate temperature, exhibit high photo- to dark-conductivity ratios for compositions of up to -25% germanium.
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