bluuebunny/crossref_metadata_2025_split huggingface dataset:
A method for tumor dosimetry based on hybrid planar‐SPECT/CT images and semiautomatic segmentation
Authors: Roth Daniel , Gustafsson Johan , Sundlöv Anna , Sjögreen Gleisner Katarina 
Published: September 2018

PurposeA hybrid planar‐SPECT/CT method for tumor dosimetry in Lu‐DOTATATE therapy, applicable to datasets consisting of multiple conjugate‐view images and one SPECT/CT, is developed and evaluated.MethodsThe imaging protocol includes conjugate‐view imaging at 1, 24, 96, and 168 h post infusion (p.i.) and a SPECT/CT acquisition 24 h p.i. The dosimetry method uses the planar images to estimate the shape of the time–activity concentration curve, which is then rescaled to absolute units using the SPECT‐derived activity concentration. The resulting time‐integrated activity concentration coefficient (TIACC) is used to calculate the tumor‐absorbed dose. Semiautomatic segmentation techniques are applied for tumor delineation in both planar and SPECT images, where the planar image segmentation is accomplished using an active‐rays‐based technique. The selection of tumors is done by visual inspection of planar and SPECT images and applying a set of criteria concerning the tumor visibility and possible interference from superimposed activity uptakes in the planar images. Five different strategies for determining values from planar regions of interest (ROIs), based on entire or partial ROIs, and with and without background correction, are evaluated. Evaluation is performed against a SPECT/CT‐based method on data from six patients where sequential conjugate‐view and SPECT/CT imaging have been performed in parallel and against ground truths in Monte Carlo simulated images. The patient data are also used to evaluate the interoperator variability and to assess the validity of the developed criteria for tumor selection.ResultsFor patient images, the hybrid method produces TIACCs that are on average 6% below those of the SPECT/CT only method, with standard deviations for the relative TIACC differences of 8%–11%. Simulations show that the hybrid and SPECT‐based methods estimate the TIACCs to within approximately 10% for tumors larger than around 10 ml, while for smaller tumors, all methods underestimate the TIACCs due to underestimations of the activity concentrations in the SPECT images. The planar image segmentation has a low operator dependence, with a median Dice similarity coefficient of 0.97 between operators. The adopted criteria for tumor selection manage to discriminate the tumors for which the absorbed‐dose deviations between the hybrid and SPECT methods are the highest.ConclusionsThe hybrid method is found suitable for studies of tumor‐absorbed doses in radionuclide therapy, provided that selection criteria regarding the visibility and overlapping activities in the planar images are applied.
Validation of the Prodromal Questionnaire–Brief in a representative sample of adolescents: Internal structure, norms, reliability, and links with psychopathology
Authors: Fonseca‐Pedrero Eduardo , Inchausti Felix , Pérez‐Albéniz Alicia , Ortuño‐Sierra Javier 
Published: September 2018

AbstractObjectivesThe main purpose of the present study was twofold: to validate the Prodromal Questionnaire–Brief (PQ‐B) in a community‐derived sample of adolescents and to examine the links between psychotic‐like experiences and emotional and behavioral problems, prosocial behavior, suicidal ideation, and bipolar‐like experiences.MethodOne thousand five hundred eighty‐eight students selected by random sampling participated in a cross‐sectional survey. The PQ‐B, Paykel Suicide Scale, Strengths and Difficulties Questionnaire, Mood Disorder Questionnaire, Penn Matrix Reasoning Test, Family Affluence Scale‐II, and Oviedo Infrequency Scale were used.ResultsThe unidimensional factorial structure of the PQ‐B items showed adequate goodness of fit index. This model also showed configural and strong invariance across gender. The internal consistency of the PQ‐B total frequency score was 0.92. A high degree of overlap was found between psychotic‐like experiences and emotional and behavioral problems, suicidal ideation, and bipolar‐like experiences.ConclusionThe PQ‐B is a brief, easy, and reliable tool for screening psychotic‐like experiences in adolescents from the general population. The assessment of risk for psychosis and its relationship with other psychopathological risk factors in a close‐in strategy or two‐stage process model may help us to enhance the early identification for youths at heightened risk for serious mental disorders.
Regional investigation of lung function and microstructure parameters by localized 129Xe chemical shift saturation recovery and dissolved‐phase imaging: A reproducibility study
Authors: Kern Agilo Luitger , Gutberlet Marcel , Qing Kun , Voskrebenzev Andreas , Klimeš Filip , Kaireit Till Frederik , Czerner Christoph , Biller Heike , Wacker Frank , Ruppert Kai , Hohlfeld Jens M. , Vogel‐Claussen Jens 
Published: September 2018

PurposeTo evaluate the reproducibility and regional variation of parameters obtained from localized 129Xe chemical shift saturation recovery (CSSR) MR spectroscopy in healthy volunteers and patients with chronic obstructive pulmonary disease (COPD) and to compare the results to 129Xe dissolved‐phase MR imaging.MethodsThirteen healthy volunteers and 10 COPD patients were scanned twice using 129Xe dissolved‐phase imaging, CSSR, and ventilation imaging sequences. A 16‐channel phased‐array coil in combination with the regularized spectral localization achieved by sensitivity heterogeneity (SPLASH) method was used to perform a regional analysis of CSSR data. Lung function and microstructural parameters were obtained using Patz model functions and their reproducibility was assessed.ResultsThe Patz model alveolar wall thickness parameter shows good reproducibility on a regional basis with a median coefficient of variation of 6.5% in healthy volunteers and 12.4% in COPD patients. Significant regional differences of lung function parameters derived from localized CSSR were found in healthy volunteers and correlations with spirometric indices were found.ConclusionLocalized 129Xe CSSR provides reproducible estimates of alveolar wall thickness and is able to detect regional differences of lung microstructure.
In vivo microscopic diffusional kurtosis imaging with symmetrized double diffusion encoding EPI
Authors: Ji Yang , Paulsen Jeffrey , Zhou Iris Yuwen , Lu Dongshuang , Machado Patrick , Qiu Bensheng , Song Yi‐Qiao , Sun Phillip Zhe 
Published: September 2018

PurposeDiffusional kurtosis imaging (DKI) measures the deviation of the displacement probability from a normal distribution, complementing the data commonly acquired by diffusion MRI. It is important to elucidate the sources of kurtosis contrast, particularly in biological tissues where microscopic kurtosis (intrinsic kurtosis) and diffusional heterogeneity may co‐exist.MethodsWe have developed a technique for microscopic kurtosis MRI, dubbed microscopic diffusional kurtosis imaging (µDKI), using a symmetrized double diffusion encoding (s‐DDE) EPI sequence. We compared this newly developed µDKI to conventional DKI methods in both a triple compartment phantom and in vivo.ResultsOur results showed that whereas conventional DKI and µDKI provided similar measurements in a compartment of monosphere beads, kurtosis measured by µDKI was significantly less than that measured by conventional DKI in a compartment of mixed Gaussian pools. For in vivo brain imaging, µDKI showed small yet significantly lower kurtosis measurement in regions of the cortex, CSF, and internal capsule compared to the conventional DKI approach.ConclusionsOur study showed that µDKI is less susceptible than conventional DKI to sub‐voxel diffusional heterogeneity. Our study also provided important preliminary demonstration of our technique in vivo, warranting future studies to investigate its diagnostic use in examining neurological disorders.
Wideband myocardial perfusion pulse sequence for imaging patients with a cardiac implantable electronic device
Authors: Hong KyungPyo , Collins Jeremy D. , Knight Bradley P. , Carr James C. , Lee Daniel C. , Kim Daniel 
Published: September 2018

AbstractPurposeTo develop a wideband cardiac perfusion pulse sequence and test whether it is capable of suppressing image artifacts in patients with a cardiac implantable electronic device (CIED), while not exceeding the specific absorption rate (SAR) limit (2.0 W/kg).MethodsA wideband perfusion pulse sequence was developed by incorporating a wideband saturation pulse to achieve a good balance between saturation of magnetization and SAR. Clinical standard and wideband perfusion MRI scans were performed back‐to‐back in a randomized order on 16 patients with a CIED undergoing clinical cardiac MRI. Two expert readers graded the artifact intensity and extent on a segmental basis using a 5‐point Likert scale, where significant artifact was defined by a composite score. The variance in myocardial signal prior to tissue‐enhancement was analyzed to quantify artifact‐intensity. Whole‐body SAR values computed by the MR scanner were read from the DICOM header. Either a paired t‐test or Wilcoxon signed‐rank test was performed to compare two groups.ResultsWhile the mean whole‐body SAR for a single‐slice wideband perfusion scan (0.38 ± 0.08W/kg) was significantly (p < 0.05) higher than for a single‐slice standard perfusion scan (0.11 ± 0.03W/kg), it was 81% below 2.0 W/kg. The mean variance in myocardial signal prior to tissue‐enhancement was significantly (p < 0.001) higher for standard (422.6 ± 306.6 a.u.) than wideband (107.0 ± 60.9 a.u.). Among 105 myocardial segments, standard produced 19 segments (18%) that were deemed to have significant artifacts, whereas wideband produced only 3 segments (3%).ConclusionA wideband perfusion pulse sequence is capable of suppressing image artifacts induced by a CIED while not exceeding SAR at 2.0 W/kg.
Assessment of Carbon Dioxide Piscicide Treatments
Authors: Cupp Aaron R. , Smerud Justin R. , Tix John A. , Rivera Jose M. , Kageyama Stacie A. , Merkes Christopher M. , Erickson Richard A. , Amberg Jon J. , Gaikowski Mark P. 
Published: September 2018

Abstract
Few chemicals are approved to control or eradicate nuisance fish populations in the United States. Carbon dioxide (CO2) is currently being developed and studied as a new piscicide option for nonselective population control. This study evaluated dry ice (solid state CO2) as a simple CO2 delivery method during winter piscicide applications. Nonnative Silver Carp Hypophthalmichthys molitrix, Bighead Carp H. nobilis, and native Fathead Minnow Pimephales promelas were overwintered together in ice-covered ponds treated with 25 kg dry ice/100,000 L (low treatment) or 50 kg dry ice/100,000 L (high treatment). Overwinter fish survival was significantly reduced in ponds treated with dry ice relative to untreated control ponds. Fathead Minnows were less susceptible to CO2 exposure than the carps, with 26–96% survival in low-treatment ponds and 4–68% survival in high-treatment ponds. Silver Carp and Bighead Carp were more sensitive to CO2 treatments and no individuals of either species survived in ponds with the high-treatment level. Water samples were also collected in all ponds throughout this study, and we observed notably higher Silver Carp and Bighead Carp environmental DNA (eDNA) concentrations in dry-ice-treated ponds relative to untreated control ponds. Distinct changes in eDNA trends correlated with fish mortality, and results indicate that eDNA sampling could be a useful indicator of piscicide efficacy. This study demonstrates that CO2 administered as dry ice is an effective under-ice piscicide method.
Mix‐&‐Read Determination of Mercury(II) at Trace Levels with Hybrid Mesoporous Silica Materials Incorporating Fluorescent Probes by a Simple Mix‐&‐Load Technique
Authors: Climent Estela , Hecht Mandy , Witthuhn Heike , Gawlitza Kornelia , Rurack Knut 
Published: September 2018

AbstractThe synthesis, characterization, and application of mesoporous materials containing boron–dipyrromethene (BODIPY) moieties that allow the sensitive and selective detection of HgII in aqueous environments by fluorescence enhancement is reported. For this purpose, BODIPY dye I containing a thia‐aza crown ether receptor as the fluorescent probe for the detection of HgII in aqueous environments is encapsulated into mesoporous materials to avoid self‐quenching or aggregation in water. Determination of HgII is accomplished within a few seconds with high selectivity and sensitivity, reaching a limit of detection of 12 ppt. The determination of trace amounts of HgII in natural waters and in fish extracts is demonstrated by using our sensing material. The incorporation of the material into several μ‐PAD strips yields a portable, cheap, quick, and easy‐to‐handle tool for trace HgII analysis in water.
PSTPIP1‐associated myeloid‐related proteinemia inflammatory syndrome: A rare cause of childhood neutropenia associated with systemic inflammation and hyperzincemia
Authors: Hashmi Saman K. , Bergstrom Katie , Bertuch Alison A. , Despotovic Jenny M. , Muscal Eyal , Xia Fan , Bi Weimin , Marcogliese Andrea , Diaz Rosa 
Published: September 2018

AbstractNeutropenia in pediatric patients can be due to a variety of disorders. We describe two patients who underwent extensive evaluation over many years for arthralgias and moderate neutropenia of unclear etiology. Genetic testing identified a pathogenic variant in PSTPIP1 (proline‐serine‐threonine phosphatase‐interacting protein 1) in both patients. Markedly elevated inflammatory markers and zinc levels confirmed the rare diagnosis of PSTPIP1‐associated myeloid‐related proteinemia inflammatory (PAMI) syndrome, tailoring treatment. Neutropenia is common in patients with PAMI syndrome. Unique mutations seen in PAMI syndrome may account for the specific phenotypic features of this disorder.
A structural reconsideration: Linear aliphatic or alicyclic hard segments for biodegradable thermoplastic polyurethanes?
Authors: Seidler Konstanze , Ehrmann Katharina , Steinbauer Patrick , Rohatschek Andreas , Andriotis Orestis G. , Dworak Claudia , Koch Thomas , Bergmeister Helga , Grasl Christian , Schima Heinrich , J. Thurner Philipp , Liska Robert , Baudis Stefan 
Published: September 2018

ABSTRACTThermoplastic polyurethane elastomers (TPUs) with a biodegradable chain extender and different nonaromatic diisocyanate hard segments were synthesized and tested concerning their thermal, mechanical, and degradation properties and for their processability regarding electrospinning. The design of the TPUs was based on the structural modification of the hard segment using linear aliphatic hexamethylene diisocyanate (HMDI), more rigid alicyclic 4,4′‐methylene bis(cyclohexylisocyanate) (H12MDI), 1,3‐bis(isocyanatomethyl)cyclohexane (BIMC), or isophorone diisocyanate (IPDI). The soft segment consisted of poly(tetrahydrofuran). Bis(2‐hydroxyethyl) terephthalate (BET) was used as chain extender with cleavable ester bonds. Some of the polyurethanes based on alicyclic diisocyanate showed better mechanical performance than the less rigid HMDI‐based TPU. The TPU in vitro degradability was tested for 25 days at elevated temperatures in PBS buffer and indicated a bulk erosion process. Electrospinning experiments were conducted and promising results with respect to further applicability of these materials in vascular tissue engineering were obtained. © 2018 The Authors Journal of Polymer Science Part A: Polymer Chemistry Published by Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 2214–2224
Synthesis and dilute solution properties of branched poly(benzyl methacrylate) using na‐clay supported aqueous‐phase catalysis
Authors: Aggarwal Ravi , Baskaran Durairaj 
Published: September 2018

ABSTRACTThe supported aqueous‐phase catalysis (SAPC) using hydrated interface has been used to synthesize branched polymers (star and graft) of benzyl methacrylate (BnMA) via atom‐transfer radical polymerization (ATRP) in the presence of Na‐clay supported catalyst in anisole at ambient temperature. The propagation of star poly(BnMA)s using diPENDTA‐Br6, as hexa‐functional initiator is confined at the hydrated interface between the support and the liquid medium as evident from the obtained polymers that are catalyst contamination‐free, and exhibited moderately narrow molecular weight distributions (Mw/Mn ≤ 1.33). The hexa‐functionality of synthesized stars is verified by 1H NMR, the measurement of their intrinsic viscosity ([η]), and radius of gyration (Rg). The polymerization was also recycled up to 5 times to produce star PBnMAs with high initiator efficiency. The star polymers prepared using hydrated Na‐clay supported is compared with star prepared using covalent silica supported catalyst system. The star polymer obtained from covalently supported catalyst gave broad Mw/Mn and poor initiator efficiency. The polystyrene‐graft‐PBnMA (PS‐g‐PBnMA) copolymer is also prepared using hydrated Na‐clay supported catalyst system in anisole at ambient temperature. The graft‐copolymer had narrow Mw/Mn and was confirmed using 1H NMR and atomic force microscopy. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 2225–2237
Facile One‐Step Synthesis of Black Phosphorus via Microwave Irradiation with Excellent Photocatalytic Activity
Authors: He Dongyang , Zhang Zhaocheng , Qu Jiao , Yuan Xing , Guan Jiunian 
Published: September 2018

AbstractA rapid one‐step microwave‐assisted liquid‐phase synthesis (MLS) method of black phosphorus (BP) is reported for the first time in this work. Under microwave irradiation, BP is generated within 45 min. The lattice spaces of the as‐prepared BP are determined as 0.338 and 0.158 nm, belonging to the (021) and (220) planes of BP, respectively. BP is grown in situ on red phosphorus (RP), which can be used directly as a metal‐free photocatalyst. The coupled BP–RP heterostructure exhibits an excellent performance in visible‐light photocatalytic degradation of methylene blue with BP acting as cocatalyst. The enhanced photocatalytic activity of BP–RP heterostructure compared with RP itself is obtained and explained in terms of the efficient separation of photogenerated electrons (eCB−) and holes (h+) due to the well‐matched energy level of BP and RP. The new‐developed MLS method holds great promise for developing an easy and efficient preparation method of BP for photocatalytic applications.
Multi‐scale observations of atmospheric moisture variability in relation to heavy precipitating systems in the northwestern Mediterranean during HyMeX IOP12
Authors: Khodayar Samiro , Czajka Beata , Caldas‐Alvarez Alberto , Helgert Sebastian , Flamant Cyrille , Di Girolamo Paolo , Bock Olivier , Chazette Patrick 
Published: September 2018

The deployment of special instrumentation for the Hydrological Cycle in the Mediterranean Experiment (HyMeX) provides a valuable opportunity to investigate the spatio‐temporal variability of atmospheric water vapour across scales in relationship with the occurrence of Heavy Precipitation Systems (HPSs) in the north Western Mediterranean (WMed) during the Intensive Observation Period (IOP12), which is the focus of this investigation. High‐resolution convection‐permitting COSMO simulations complement the observational network and allow the calculation of on‐line trajectories.In addition to the presence of a favourable large‐scale situation and low‐level convergence, atmospheric moisture changes resulting in conditionally unstable air are identified as responsible for convective initiation (CI). All HPSs within the north‐WMed form in periods/areas of maximum integrated water vapour (IWV; 35–45 kg/m2) after an increase of about 10–20 kg/m2. The most intense events receive moisture from different sources simultaneously and show a sudden increase of about 10 kg/m2 between 6 and 12 h prior to the event, whereas in the less intense events the increase is larger, about 20 kg/m2, over a period of at least 24–36 h. Changes in the lower (∼900 hPa) and mid‐troposphere (∼700 hPa) control the evolution of the atmospheric moisture and the instability increase prior to CI. Spatial inhomogeneities in the lower boundary layer determine the timing and location of deep convection, whereas enhanced moisture in the mid‐troposphere favours intensification. Moister and deeper boundary layers, with updraughts reaching up to 2 km are identified in those pre‐convective environments leading to HPS, whereas dry, shallow boundary layers are found everywhere else. The build‐up time and vertical distribution of the moisture changes are found to be crucial for the evolution and severity of the HPSs rather than the amount of total column atmospheric moisture.
Failure time distributions for complex equipment
Authors: Collins David H. , Warr Richard L. 
Published: September 2018

AbstractThe exponential distribution is inadequate as a failure time model for most components; however, under certain conditions (in particular, that component failure rates are small and mutually independent, and failed components are immediately replaced or perfectly repaired), it is applicable to complex repairable systems with large numbers of components in series, regardless of component distributions, as shown by Drenick in 1960. This result implies that system behavior may become simpler as more components are added. We review necessary conditions for the result and present some simulation studies to assess how well it holds in systems with finite numbers of components. We also note that Drenick's result is analogous to similar results in other systems disciplines, again resulting in simpler behavior as the number of entities in the system increases.
Following the Kinetics of Barium Titanate Nanocrystal Formation in Benzyl Alcohol Under Near‐Ambient Conditions
Authors: Veldhuis Sjoerd A. , Stawski Tomasz M. , Gonzalez Rodriguez Pablo , Yuan Huiyu , Besselink Rogier , Benning Liane G. , ten Elshof Johan E. 
Published: September 2018

AbstractIn complex chemical syntheses (e.g., coprecipitation reactions), nucleation, growth, and coarsening often occur concurrently, obscuring the individual processes. Improved knowledge of these processes will help to better understand and optimize the reaction protocol. Here, a form‐free and model independent approach, based on a combination of time‐resolved small/wide‐angle X‐ray scattering, is employed to elucidate the effect of reaction parameters (such as precursor concentration, reactant stoichiometry, and temperature) on the nucleation, crystallization, and growth phenomena during the formation of nanocrystalline barium titanate. The strength of this approach is that it relies solely on the total scattered intensity (i.e., scattering invariant) of the investigated system, and no prior knowledge is required. As such, it can be widely applied to other synthesis protocols and material's systems. Through the scattering invariant, it is found that the amorphous‐to‐crystalline transformation of barium titanate is predominantly determined by the total amount of water released from the gel‐like barium hydroxide octahydrate precursor, and three rate‐limiting regimes are established. As a result of this improved understanding of the effect of varying reaction conditions, elementary boundary conditions can be set up for a better control of the barium titanate nanocrystal synthesis.