Search

In this paper, we address the problem of cooperative mapping (CM) using datasets collected by multiple users at different times, when the transformation between the users’ starting poses is unknown. Specifically, we formulate CM as a constrained optimization problem, in which each user's independently estimated trajectory and map are merged together by imposing geometric constraints between commonly observed point and line features. Additionally, we provide an algorithm for efficiently solving the CM problem, by taking advantage of its structure. The proposed solution is proven to be batch-least-squares (BLS) optimal over all users’ datasets, while it is less memory demanding and lends itself to parallel implementations. In particular, our solution is shown to be faster than the standard BLS solution, when the overlap between the users’ data is small. Furthermore, our algorithm is resource-aware as it is able to consistently trade accuracy for lower processing cost, by retaining only an informative subset of the common-feature constraints. Experimental results based on visual and inertial measurements collected from multiple users within large buildings are used to assess the performance of the proposed CM algorithm.

Magnetic resonance imaging (MRI) is the most sensitive imaging technique for the detection of bone marrow infiltration, and has therefore recently been included in the new diagnostic myeloma criteria, as proposed by the International Myeloma Working Group. Nevertheless, conventional MRI only provides anatomical information and is therefore only of limited use in the response assessment of patients with multiple myeloma. The additional information from functional MRI techniques, such as diffusion-weighted imaging and dynamic contrast-enhanced MRI, can improve the detection rate of bone marrow infiltration and the assessment of response. This can further enhance the sensitivity and specificity of MRI in the staging of multiple myeloma patients. This article provides an overview of the technical aspects of conventional and functional MRI techniques with practical recommendations. It reviews the diagnostic performance, prognostic value, and role in therapy assessment in multiple myeloma and its precursor stages.

In this paper, we present a novel approach to shared augmented reality (AR) for mobile devices operating in the same area that does not rely on cloud computing. In particular, each user’s device processes the visual and inertial data received from its sensors and almost immediately broadcasts a partial feature map of its surroundings. In parallel, every device localizes against the broadcasted maps by employing feature observations to determine its 4-DOF transformation to each of the gravity-aligned maps. By doing so, virtual content placed by any of the users is quickly and accurately displayed in all other users’ views. Furthermore, to reduce the effect of inconsistency introduced by relocalizing against incrementally created and updated maps, their transformations w.r.t. the device are modeled as random processes driven by white noise instead of constant, unknown parameters. Lastly, we assess the accuracy of our approach for the case of two users in a room-scale environment against VICON ground-truth.

Purpose To evaluate the value of the combined evaluation of SE MRI, dynamic contrast enhanced MRI (DCE-MRI) and diffusion weighted imaging (DWI) in multiple myeloma (MM) patients after treatment compared to the international myeloma working group (IMWG) response criteria. Materials and methods The retrospective study includes 27 newly diagnosed patients, providing 99 MRI-investigations. Patients were categorized according to the IMWG response criteria. Quantitative assessment was based on signal intensities (SI) of T1-weighted, fat-saturated T2-weighted and b1000 images, apparent diffusion coefficients (ADC) and parameters from time-intensity-curves (TIC) derived from L3. Qualitative visual analysis of conventional MRI-images, b1000-images and TICs, providing a “combined skeletal score”, was used to create MRI response criteria. Results The combined skeletal score could significantly differentiate between subgroups based on IMWG response criteria ( p = 0.016). The gold standard plasmacytosis could significantly differentiate between subgroups based on MRI response criteria ( p p p = 0.006). There is a good agreement between IMWG and MRI response criteria (Kendall’s coefficient = 0.761). Conclusion Response evaluation of MM-patients based on the combination of anatomical information from conventional MRI with functional information from DCE-MRI and DWI, is useful for monitoring therapy.

Root zone soil moisture (RZSM) is an essential variable in meteorology, hydrology, and agriculture. Current methods in passive and active microwave remote sensing at L-band (e.g. SMOS or SMAP) are limited to a sensing depth of less than 10 cm. Observing RZSM (water in the top meter of soil) will require lower frequencies (P-band), presenting significant difficulties for a spaceborne instrument, due to the required antenna size, the presence of radio-frequency interference (RFI), and competition for spectrum allocations (in the case of active radar). Bistatic radar using Signal of Opportunity (SoOp) (e.g. digital satellite transmitters) offers the possibility of remote sensing using powerful signals already occupying bands allocated for communications. This paper will present early results from the first airborne campaign to study P-band reflectometry for soil moisture, conducted in Oklahoma between October 17–26, 2016. A geosynchronous communication satellite, transmitting a 25 KHz data signal on a 260.375 MHz carrier was uses at the signal source. Preliminary assessment of the data showed high reflectivity over a lake and consistent results between subsequent overflights of the watershed. Recently, a tower experiment has started using a 20 MHz wide signal centered at 370 MHz. Linearly polarized measurements were made over bare soil between 25-May-2017 and 8-June-2017 observing a strong reflected signal. Corn is being planted on the field and measurements will be made throughout the growing season.

In this paper, we address the problem of cooperative mapping (CM) using datasets collected by multiple users at different times, when the transformation between the users' starting poses is unknown. Specifically, we formulate CM as a constrained optimization problem, where each user's independently estimated trajectory and map are combined in a single map by imposing geometric constraints between commonly-observed point and line features. Furthermore, our formulation allows for modularity since new/old maps (or parts of them) can be easily added/removed with no impact on the remaining ones. Additionally, the proposed CM algorithm lends itself, for the most part, to parallel implementations, hence gaining in speed. Experimental results based on visual and inertial measurements collected from four users within two large buildings are used to assess the performance of the proposed CM algorithm.

In this paper, we seek to provide consistent, real-time 3D localization capabilities to mobile devices navigating within previously mapped areas. To this end, we introduce the Cholesky-Schmidt-Kalman filter (C-SKF), which explicitly considers the uncertainty of the prior map, by employing the sparse Cholesky factor of the map's Hessian, instead of its dense covariance-as is the case for the Schmidt-Kalman filter. By doing so, the C-SKF has memory requirements typically linear in the size of the map, as opposed to quadratic for storing the map's covariance. Moreover, and in order to bound the processing needs of the C-SKF (between linear and quadratic in the size of the map), we introduce two relaxations of the C-SKF algorithm: (i) The sC-SKF, which operates on the Cholesky factors of independent sub-maps resulting from dividing the map into overlapping segments. (ii) We formulate an efficient method for sparsifying the Cholesky factor by selecting and processing a subset of loop-closure measurements based on their temporal distribution. Lastly, we assess the processing and memory requirements of the proposed algorithms, and compare their positioning accuracy against other inconsistent map-based localization approaches that employ measurement-noise-covariance inflation to compensate for the map's uncertainty.

Magnetic resonance imaging (MRI) is increasingly being used in the diagnostic work-up of patients with multiple myeloma. Since 2014, MRI findings are included in the new diagnostic criteria proposed by the International Myeloma Working Group. Patients with smouldering myeloma presenting with more than one unequivocal focal lesion in the bone marrow on MRI are considered having symptomatic myeloma requiring treatment, regardless of the presence of lytic bone lesions. However, bone marrow evaluation with MRI offers more than only morphological information regarding the detection of focal lesions in patients with MM. The overall performance of MRI is enhanced by applying dynamic contrast-enhanced MRI and diffusion weighted imaging sequences, providing additional functional information on bone marrow vascularization and cellularity. This pictorial review provides an overview of the most important imaging findings in patients with monoclonal gammopathy of undetermined significance, smouldering myeloma and multiple myeloma, by performing a 'total' MRI investigation with implications for the diagnosis, staging and response assessment. Main message aEuro cent Conventional MRI diagnoses multiple myeloma by assessing the infiltration pattern. aEuro cent Dynamic contrast-enhanced MRI diagnoses multiple myeloma by assessing vascularization and perfusion. aEuro cent Diffusion weighted imaging evaluates bone marrow composition and cellularity in multiple myeloma. aEuro cent Combined morphological and functional MRI provides optimal bone marrow assessment for staging. aEuro cent Combined morphological and functional MRI is of considerable value in treatment follow-up.

To evaluate DWI of the bone marrow in the differentiation of monoclonal gammopathy of undetermined significance (MGUS), smouldering myeloma (SMM) and multiple myeloma (MM).The retrospective study includes 64 patients with MGUS, 27 with SMM, 64 with new MM and 12 controls. Signal intensity (SI) of spinal SE-MRI and DWI (b0-1000) as well as apparent diffusion coefficients (ADC) were measured in the T10 and L3. Qualitative assessment of b-images was performed by one experienced radiologist.ADC600 and ADC1000 are the best ADC values in differentiating patient groups (p 0.030). SIT2, SIb1000 and ADC1000 are higher and SIT1 lower in L3 compared to T10 (p 0.050). All quantitative parameters of L3 can differentiate significantly between MGUS and MM (p 0.050) and between patients with percentage plasma cells (PC%) between 0-10 % compared to50 % (p = 0.001). Only SIT2 for L3 can differentiate MGUS from SMM (p = 0.044) and PC%0-10 from PC%10-25 (p = 0.033). Qualitative interpretation of b1000 images allows differentiating MM patients from those with MGUS or SMM (p 0.001).Spinal SE-MRI can differentiate among MGUS, SMM, MM and control subjects. DWI based on the SI on b1000 images and ADC values is increased in MM compared to MGUS and SMM. Qualitative assessment of b-images can differentiate MM from MGUS or SMM.• ADC values are higher in patients with MM compared to MGUS • DWI parameters change late in disease evolution • DWI is sensitive but not specific in diagnosing patients with MM • Qualitative DWI assessment is good in detecting myeloma patients.

Single-photon ionization of the HeH${}^{2+}$ molecular ion exposed to an attosecond x-ray laser pulse is investigated for photon energies of 200 and 300 eV. In the fixed-nuclei approximation, the temporal response of the system is obtained by solving the time-dependent Schr\"odinger equation through an ab initio time-dependent grid-based discrete-variable representation formulated in two-center prolate spheroidal coordinates. The two-center interference effect is clearly observable in the excited $2p\ensuremath{\sigma}$ state, whereas interference patterns almost disappear, in both the parallel and perpendicular geometries, when the system is started from the $1s\ensuremath{\sigma}$ ground state. The angular distributions are asymmetric with respect to the center between the helium and hydrogen nuclei. For the $2p\ensuremath{\sigma}$ state in the parallel geometry, a dynamically forbidden mode of photoionization is observed only on one side of the two nuclei, with the details depending on the laser parameters and the internuclear separation. We also address the similarities and differences between a plane-wave model for the ejected electron with a linear combination of atomic orbitals for the molecular bound states and the classical double-slit-like interference pattern.

To compare the ability of a computerized method of sperm morphology with the manually recorded method in predicting in vitro fertilization (IVF) results, to compare results obtained by both methods, and to determine the intraobservation variability.Forty-three stained semen slide preparations from two large level-three academic institutions' reproductive endocrinology units (IVF programs) were blindly evaluated, and the sperm were classified into normal and amorphous forms.Experiment 1: Twenty-one slide preparations from the Tygerberg gamete intrafallopian transfer program were manually evaluated; the fertilization rates for the groups with14% and14% normal sperm forms were 33.3% (15/45 oocytes) and 76.6% (46/60 oocytes), respectively. Corresponding fertilization rates with FERTECH were 46.8% (30/64) and 75.6% (31/41). Experiment 2: Twenty-two slide preparations from the Norfolk IVF program were evaluated. The manual method reported a fertilization rate in the group with14% normal forms of 27.4% (14/51 oocytes) compared with 90.0% (127/141 oocytes) in the group with14% normal forms. Corresponding figures for the FERTECH method were 33.9% (18/53) and 88.4% (123/139), respectively. Experiment 3: When the 43 slide preparations were blindly evaluated using both methods, 84% of the FERTECH evaluations correlated well with the manual method and FERTECH ability to diagnose the subfertile male (14% normal forms) was 95% (sensitivity). Experiment 4: A total of 16 different slides (8 per group) were randomly selected and analyzed five times (100 cells per reading) by the computerized method. The slides were obtained from men with normal sperm morphology of14% and14% as classified by the manual method. In the first group (14%) 97.5% (39/40) of the readings classified the sperm in the proper category, whereas in the second group (14%) 95% (38/40) of the cases were correctly identified.Using strict criteria for morphology evaluation, there is a positive and significant correlation between FERTECH evaluation and manual assessment. The reproducibility of the computerized method and the ability to distinguish between fertile and subfertile groups using those criteria are good.

Left ventricular failure results from many myocardial diseases: the symptoms of left ventricular failure are the consequence of adaptations which the left ventricle and circulatory system activate to counteract the initial myocardial disease. The aims of treatment of cardiac failure are diverse depending on whether treatment is directed to correct the initial myocardial disease, its myocardial consequences, its circulatory consequences or, more simply, the patient's symptoms. The ideal treatment of cardiac failure would include a drug acting on the cause, a drug restoring left ventricular contraction and relaxation adapted to the conditions of cardiac load, a drug correcting regional blood flow disturbances and a drug relieving symptoms related to salt retention. An ideal drug for chronic left ventricular failure does not exist, and so treatment is a composite effort. Should it be in first intention? This is the current trend.

Left ventricular failure is caused by a variety of myocardial diseases and its symptoms results from adjustments attempted by the left ventricle and the circulatory system to cope with the initial myocardial pathology. Treatment of heart failure has various objectives, depending on whether one tries to correct the initial myocardial disease, or its consequences on the myocardium, or its repercussions on blood circulation, or, more simply, to alleviate the symptoms experienced by the patient. The ideal treatment of heart failure would include a drug acting on its cause, another drug to restore a degree of contraction and relaxation adjusted to the amount of load, a third drug bringing back to normal a perturbed peripheral circulation and a fourth drug to relieve the symptoms due to sodium retention. Such a treatment does not exist, and the management of chronic left ventricular failure can only be composite. Should it be prescribed from the start? This, increasingly, is the current trend.

Calmodulin content and distribution between soluble and particulate fractions were determined by radioimmunoassay in six human melanoma cell lines exhibiting differences in tumor origin (primary or metastatic), degree of tumorigenicity and of pigmentation (amelanotic or melanotic). The results indicate that a) total, soluble and particulate calmodulin levels expressed as ng/10(6) cells or ng/micrograms of proteins remained constant for five out of six cell lines when cells grew from subconfluency to confluency. For IGR 37 line, derived from metastatic melanoma, the calmodulin content decreases from 2.39 to 1.27 ng/micrograms protein for total calmodulin, from 2.17 to 1.52 ng/micrograms protein for soluble calmodulin and from 2.61 to 1.02 ng/micrograms protein for particulate calmodulin, b) total, soluble and particulate calmodulin levels expressed as ng/microgram proteins were twofold (at confluency) to fourfold (at subconfluency) higher in the two cell lines from metastatic origin, IGR 37 and IPC 167. As for example, for total calmodulin, values in IGR 37 and IPC 167 cell lines, were, respectively at subconfluency, 2.39 and 2.31 ng/micrograms protein as compared with the four other cell lines: 0.76 to 0.96 ng/micrograms protein and at confluency: 1.27 and 1.98 ng/micrograms protein as compared with the four other cell lines: 0.76 to 0.90 ng/micrograms protein, c) ratio of calmodulin between soluble and particulate fractions was about 1 for the two autologous cell lines IGR 37 and IGR 39 and varies from 2 to 3 for the four other cell lines.

It is emphasized that, under certain conditions, the frequency dependences of the real and imaginary parts of an electrical impedance are correlated by the Kramers-Kronig relations. The importance of these relations in electrochemistry is illustrated by the examples of certain electrochemical impedance types. Some misapprehensions appearing in the electrochemical literature are pointed out.

An experimental investigation was made on the electrode properties of oxidized Ti and of rutile single crystals. Polycrystalline samples were prepared by oxidation in air and partial reduction in H2 at various temperatures. The current-voltage characteristics in aqueous-indifferent electrolyte solutions in darkness and under illumination demonstrate that it is possible to obtain samples with photoelectrolytic performances at least equivalent to those of monocrystalline TiO2 samples. Moreover, a pronounced similarity is found between both types of electrodes with regard to the reactivity of the reducing agents added. The influence of different gases (H2, N2 or O2) on the current-voltage behaviour of these electrodes reveals some important aspects concerning their possible use for the conversion of optical energy into chemical or electrical energy.

The impedance of several nearly ideally polarizable semiconductor electrodes (CdSe, CdS, TiO2) has been studied as a function of applied voltage and of frequency. The differential capacitance and resistance appear to obey to simple frequency laws. A mathematical model accounting for these laws is presented, in which a distribution of time constants is assumed, associated with dielectric relaxation phenomena in the double layer at the semiconductor/electrolyte interface. The experimental results indicate, that the source of the frequency-dependence has to be sought in structural irregularities of the surface region of the electrode. The proposed model appears to be also applicable to results, mentioned in the literature, concerning other semiconductor/electrolyte systems. The possibility of determining the flat-band potential from frequency-dependent capacitance data is discussed. Die Impedanz verschiedener fast ideal polarisierbaren Halbleiterelektroden (CdSe, CdS, TiO2) wurde in Abhangigkeit von der angelegten Spannung und der Frequenz untersucht. Die Differentialkapazitat und der Differentialwiderstand zeigen einfache Frequenzabhangigkeiten. Diese Gesetze werden aufgrund eines mathematischen Modells gedeutet, in dem eine Verteilung von Zeitkonstanten angenommen wird, die mit dielektrischen Relaxationserscheinungen in der Doppelschicht an der Halbleiter/Elektrolyt-Phasengrenze in Zusammenhang stehen. Die Ergebnisse deuten darauf hin, Strukturdefekte im Oberflachengebiet der Elektrode seien fur die Frequenzabhangigkeit verantwortlich. Es zeigt sich, das das vorgeschlagene Modell auch auf Literaturergebnisse betreffs anderer Halbleiter/Elektrolyt-Systeme anwendbar ist. Die Moglichkeit, das Flachbandpotential aus frequenzabhangigen Kapazitatsergebnissen zu bestimmen, wird besprochen.

The behaviour of several reactants at the illuminated TiO2 anode has been investigated. Current multiplication, indicating a two-step electrochemical oxidation mechanism in which both the valence and the conduction band of rutile are involved, was found with several inorganic and organic reactants. From the study of competitive electrochemical processes, it was concluded that several other reactants are oxidized by holes solely. In certain cases, it has been possible to obtain quantitative data concerning relative hole reactivities. Possible reaction schemes, the origin of the ρH-dependence of the multiplication factor, and the applicability of the direct electron transfer model to the reactions observed are discussed.

Classical psychological twin studies have yielded in part equivocal and sometimes contradictory results. Besides the complexity of the problem, the delicate character of the diagnosis, and the rudimentary tools which were used, several other factors are underlying this situation: (1) insufficient systematization of the set-up and the careless design of the investigations; (2) lack of follow-up studies; (3) uncertain diagnosis of zygosity; in MZ twins no attention to the age of the ovum at the time of cleavage; (4) lack of consideration for antenatal and perinatal influences; (5) no attention to the typical circumstances linked to the twin situation. All this makes it difficult to balance nature against nurture on the basis of comparison between MZ twins, DZ twins, and singletons. Interactions may also appear between the effect of twinning and other factors such as the socioeconomic circumstances. A new investigation was therefore started where, besides the twins, a group of matched control singletons was constituted. The follow-up study is now completed up to the age of 5 years in 13 MZ and 20 DZ twin pairs (+ controls, that is to say, 99 children).The children were observed and subjected to psychological tests at the age of 6 months and of 1, 2, 3, 4, and 5 years.

The electrochemical behaviour of semiconducting TiO2 electrodes has been investigated by means of impedance, current and potential measurements in darkness, and as well in indifferent electrolyte as in redox electrolyte solutions. The results allow the determination of the flat-band potential and of the position of the energy band edges at the TiO2 surface. The data obtained on electrochemical reactivity, both anodically and cathodically, appear to be qualitatively interpretable on the basis of the accepted theories for direct electron transfer at the semiconductor/electrolyte interface. Some particular features inherent to the TiO2/electrolyte system are discussed. Das elektrochemische Verhalten halbleitender TiO2-Elektroden wurde im Dunkeln durch Impedanz-, Strom- und Spannungsmessungen, sowohl in indifferenten Elektrolyt- wie in Redoxelektrolyt-Losungen untersucht. Die Ergebnisse lassen die Bestimmung des Flachbandpotentials und der energetischen Lage der Bandkanten an der TiO2-Oberflache zu. Es zeigt sich, das die anodischen und kathodischen Reaktivitatsergebnisse aufgrund der allgemein angenommenen Theorien fur direkten Elektronenubergang an der Halbleiter/Elektrolyt-Phasengrenze qualitativ interpretierbar sind. Einige dem TiO2/Elektrolyt-System inharente Eigentumlichkeiten werden besprochen.

The photolytic cage effect is studied over a wide density range of several bath gases in the laser flash photolysis of iodine at 694.3 nm. Particular attention is paid to measurements in the ‘‘simple’’ solvents Xe and Kr, which are compared with molecular dynamics calculations. Measurements in polyatomic gases and liquids are also reported, as well as the variation of the cage effect with temperature and applied magnetic field. While measuring the cage effect under such a wide variety of conditions, we simultaneously obtain the second order rate constants for iodine atom combination, which help to establish the detailed mechanism of this elementary chemical reaction.

The first hint to the nature of the thyroid microsomal antigen was provided by the observation that TPO was antigenical1y related to the microsomal antigen1. Then TPO was purified by monoclonal antibody (mAb) assisted affinity chromatography and shown to react with autoimmune antibodies (aAb) in serum of patients with autoimmune thyroid diseases 2. Titers of anti-TPO and anti-microsomal aAb in serum were found significantly correlated3 which suggested that TPO effectively was the microsomal antigen. Other groups of investigators confirmed that anti-thyroid aAb reacted with TPO, but proposed that TPO was only a part of a putative microsomal antigen complex 5 - 8. To answer the question whether TPO effectively was the microsomal antigen or only a part of i t we undertook different experiments based on the use of highly purified human TPO and mAb to it 9-11

Using calmodulin antibody, evidence for the presence of calmodulin, a calcium-binding protein modulator of numerous enzymes was shown by indirect immunofluorescence in 9 cell lines of cultured human malignant melanocytes. Calmodulin was localized in cytoplasm and in higher concentration in the perinuclear region. These observations agree with the distribution of calmodulin-binding proteins in cytoplasm and membranes.

Platelet inhibitors have widely been studied in various clinical situations resulting from atherosclerosis of the coronary arteries. At present, aspirin is virtually the only drug that has proved to be effective in all cases where the risk of coronary thrombosis was very high. Administered in daily doses of 160 to 1,500 mg, acetylsalicylic acid reduces the frequency of coronary thrombosis and its consequence, myocardial infarction, in the following clinical situations: year following myocardial infarction, acute phase of myocardial infarction, unstable angina, year following aorto-coronary bypass, days following dilatation of the coronary arteries. Acetylsalicylic acid has been compared with heparin and anti-vitamin K agents in four trial: whatever the model studied, no difference was found in the effectiveness of the two treatments tested. Aspirin ha recently been reported as preventing myocardial infarction in healthy subjects. The practical value of this finding is questionable. The various effects of aspirin have been ascribed to the fact that it interrupts a cascade of events ranging from rupture of atherosclerosis plaques to arterial thrombosis.

Introduction A number of recent investigations have demonstrated that sensory deprivation can induce transient but severe cognitive, emotional, and behavioral changes in man. 1,2 Sensory deprivation has been utilized as a technique for producing stress of a nonspecific type, capable of eliciting specific behavioral and physiological responses under controlled conditions. The advent of recent bioassay and biochemical techniques has permitted the separation and analysis of the adrenal medullary hormones, epinephrine and norepinephrine, in man. Work by von Euler 4 established that epinephrine normally is secreted only by the adrenal medulla, while norepinephrine is secreted primarily by the endings of peripheral sympathetic nerves and secondarily by the adrenal medulla. Since the early work of Cannon 5,6 and his associates, it has been known that a variety of stress situations may produce an adrenal medullary hormonal response, as reflected in alterations of cardiovascular function.