bluuebunny/crossref_metadata_2025_split huggingface dataset:
Imaging FlowCytobot modified for high throughput by in‐line acoustic focusing of sample particles
Authors: Olson Robert J. , Shalapyonok Alexi , Kalb Daniel J. , Graves Steven W. , Sosik Heidi M. 
Published: September 2017

AbstractImaging FlowCytobot, a submersible instrument that measures optical properties and captures images of nano‐ and microplankton‐sized particles, has proved useful in plankton studies, but its sampling rate is limited by the ability of hydrodynamic focusing to accurately position flowing sample particles. We show that IFCB's sampling rate can be increased at least several‐fold by implementing in‐line acoustic focusing upstream of the flow cell. Particles are forced to the center of flow by acoustic standing waves created by a piezo‐electric transducer bonded to the sample capillary and driven at the appropriate frequency. With the particles of interest confined to the center of the sample flow, the increased size of the sample core that accompanies increased sample flow rate no longer degrades image and signal quality as it otherwise would. Temperature affects the optimum frequency (through its effect on the speed of sound in water), so a relationship between sample temperature and optimum frequency for acoustic focusing was determined and utilized to control the transducer. The modified instrument's performance was evaluated through analyses of artificial particles, phytoplankton cultures, and natural seawater samples and through deployments in coastal waters. The results show that large cells, especially dinoflagellates, are acoustically focused extremely effectively (which could enable, for example, > 10‐fold increased sampling rate of harmful algal bloom species, if smaller cells are ignored), while for nearly all cell types typically monitored by IFCB, threefold faster data accumulation was achieved without any compromises. Further increases are possible with more sophisticated software and/or a faster camera.
Freshwater sample preservation for the analysis of dissolved low molecular mass thiols
Authors: Leclerc Maxime , Planas Dolors , Amyot Marc 
Published: September 2017

AbstractLow molecular mass (LMM) thiols are ubiquitous organosulfur peptides that play key roles in biogeochemical element cycling. These LMM thiols, found at low concentrations in the water column, are highly sensitive to oxidation and degradation processes which may lead to problems with detection and analysis. Natural water samples should be stored and handled appropriately to reduce thiol loss in the time period from sampling to analysis. Storage temperatures were investigated for optimal preservation of four thiols species. Thiol degradation varied between species and was generally slower in samples stored at −80°C and 4°C compared to −20°C and 21°C. Two natural freshwater matrices were tested, one from a fluvial lake subject to agricultural inputs and one from an oligotrophic pristine lake. After 6 d of storage at −20°C, the most affected thiol species was glutathione with a degradation rate (kD) of (3.0 ± 0.5) × 10−3 h−1 in the fluvial lake water and l‐cysteine‐l‐glycine (CYS‐GLY) with a kD of (3.8 ± 0.8) × 10−3 h−1 in the oligotrophic lake water. Argon purging of samples did not prevent thiol degradation or oxidation after storage for 7 d. Pre‐concentration by freeze‐drying techniques led to significant loss for every thiol species tested (up to 65% for cysteine). We recommend improving storage methods by using temperatures of −80°C or 4°C. The use of correction factors to estimate initial thiol concentrations is possible but should be used with caution due to highly site‐specific kD in natural waters.
Littlewood–Paley characterizations of higher‐order Sobolev spaces via averages on balls
Authors: He Ziyi , Yang Dachun , Yuan Wen 
Published: September 2017

AbstractIn this article, the authors characterize higher‐order Sobolev spaces , with , and , or with , and , via the Lusin area function and the Littlewood–Paley ‐function in terms of ball averages, where denotes the maximal integer not greater than . Moreover, the authors also complement the above results in the endpoint cases of p via establishing some weak type estimates. These improve and develop the corresponding known results for Sobolev spaces with smoothness order .
Graphene Oxide (GO) as Stabilizer for Preparing Chirally Helical Polyacetylene/GO Hybrid Microspheres via Suspension Polymerization
Authors: Li Jun , Deng Jinrui , Li Weifei , Pan Kai , Deng Jianping 
Published: September 2017

AbstractHybrid materials consisting of polymers and graphene are gathering ever‐growing interest. This article reports a novel methodology for preparing chirally helical polyacetylene/graphene hybrid microspheres (MPs) via suspension polymerization in which graphene oxide (GO) or alkynylated GO (MGO) serves as a sole stabilizer. Such polymerizations show remarkable advantages in circumventing the difficulties in usual suspension polymerizations and especially in directly providing clean hybrid MPs. Scanning electron microscopy (SEM), Raman spectra, and electron dispersive spectroscopy indicate that graphene sheets cover the MPs through physical interaction (GO) or covalent bonds (MGO). The hybrid MPs are also characterized by Fourier‐transform infrared spectroscopy (FT‐IR), X‐ray photoelectron spectroscopy, and thermogravimetric analysis. Circular dichroism spectra demonstrate that the polymer chains constituting the MPs adopt predominantly one‐handed helices, endowing the MPs with intriguing optical activity. The established strategy opens a new approach for preparing hybrid MPs constructed by acetylenic polymers and GO.
Voxel‐based multimodel fitting method for modeling time activity curves in SPECT images
Authors: Sarrut David , Halty Adrien , Badel Jean‐Noel , Ferrer Ludovic , Bardiès Manuel 
Published: September 2017

PurposeEstimating the biodistribution and the pharmacokinetics from time‐sequence SPECT images on a per‐voxel basis is useful for studying activity nonuniformity or computing absorbed dose distributions by convolution of voxel kernels or Monte‐Carlo radiation transport. Current approaches are either region‐based, thus assuming uniform activity within the region, or voxel‐based but using the same fitting model for all voxels.MethodsWe propose a voxel‐based multimodel fitting method (VoMM) that estimates a fitting function for each voxel by automatically selecting the most appropriate model among a predetermined set with Akaike criteria. This approach can be used to compute the time integrated activity (TIA) for all voxels in the image. To control fitting optimization that may fail due to excessive image noise, an approximated version based on trapezoid integration, named restricted method, is also studied. From this comparison, the number of failed fittings within images was estimated and analyzed. Numerical experiments were used to quantify uncertainties and feasibility was demonstrated with real patient data.ResultsRegarding numerical experiments, root mean square errors of TIA obtained with VoMM were similar to those obtained with bi‐exponential fitting functions, and were lower (< 5% vs. > 10%) than with single model approaches that consider the same fitting function for all voxels. Failure rates were lower with VoMM and restricted approaches than with single‐model methods. On real clinical data, VoMM was able to fit 90% of the voxels and led to less failed fits than single‐model approaches. On regions of interest (ROI) analysis, the difference between ROI‐based and voxel‐based TIA estimations was low, less than 4%. However, the computation of the mean residence time exhibited larger differences, up to 25%.ConclusionsThe proposed voxel‐based multimodel fitting method, VoMM, is feasible on patient data. VoMM leads organ‐based TIA estimations similar to conventional ROI‐based method. However, for pharmacokinetics analysis, studies of spatial heterogeneity or voxel‐based absorbed dose assessment, VoMM could be used preferentially as it prevents model overfitting.
Fast dynamic ventilation MRI of hyperpolarized 129Xe using spiral imaging
Authors: Doganay Ozkan , Matin Tahreema N. , Mcintyre Anthony , Burns Brian , Schulte Rolf F. , Gleeson Fergus V. , Bulte Daniel 
Published: September 2017

PurposeTo develop and optimize a rapid dynamic hyperpolarized 129Xe ventilation (DXeV) MRI protocol and investigate the feasibility of capturing pulmonary signal‐time curves in human lungs.Theory and MethodsSpiral k‐space trajectories were designed with the number of interleaves Nint = 1, 2, 4, and 8 corresponding to voxel sizes of 8 mm, 5 mm, 4 mm, and 2.5 mm, respectively, for field of view = 15 cm. DXeV images were acquired from a gas‐flow phantom to investigate the ability of Nint = 1, 2, 4, and 8 to capture signal‐time curves. A finite element model was constructed to investigate gas‐flow dynamics corroborating the experimental signal‐time curves. DXeV images were also carried out in six subjects (three healthy and three chronic obstructive pulmonary disease subjects).ResultsDXeV images and numerical modelling of signal‐time curves permitted the quantification of temporal and spatial resolutions for different numbers of spiral interleaves. The two‐interleaved spiral (Nint = 2) was found to be the most time‐efficient to obtain DXeV images and signal‐time curves of whole lungs with a temporal resolution of 624 ms for 13 slices. Signal‐time curves were well matched in three healthy volunteers. The Spearman's correlations of chronic obstructive pulmonary disease subjects were statistically different from three healthy subjects (P < 0.05).ConclusionThe Nint = 2 spiral demonstrates the successful acquisition of DXeV images and signal‐time curves in healthy subjects and chronic obstructive pulmonary disease patients. Magn Reson Med 79:2597–2606, 2018. © 2017 The Authors Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance in Medicine. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
Respiratory variation in left ventricular cardiac function with 3D double golden‐angle whole‐heart cine imaging
Authors: Holst Karen , Ugander Martin , Sigfridsson Andreas 
Published: September 2017

PurposeTo develop a 3‐dimensional free‐breathing cardiovascular MR technique for quantifying the variation in left ventricular end‐diastolic volume (LVEDV) during the respiratory cycle.MethodsA 3‐dimensional radial trajectory with double golden‐angle ordering was used for free‐running data acquisition during free breathing in healthy volunteers (N = 8). A respiratory self‐gating signal was extracted from the center of k‐space, and data were retrospectively binned into eight respiratory phases in end‐diastole. Three‐dimensional image volumes with 2‐mm isotropic spatial resolution were reconstructed with conjugate‐gradient sensitivity encoding for acquisition durations of 4.5, 9, and 25 min. The LVEDV was manually segmented for each respiratory phase and acquisition duration.ResultsRespiratory‐induced variation expressed as minimum LVEDV (during mid‐inspiration) relative to maximum LVEDV (during mid‐expiration) was 5.9 ± 0.3% for 4.5 min, 5.3 ± 0.4% for 9 min (P = 0.64 versus 4.5 min), and 5.0 ± 0.4% for 25 min (P = 0.25 versus 4.5 min, and P = 1.00 versus 9 min).ConclusionsThe proposed technique enables high spatial‐resolution quantification of the respiratory variation in LVEDV during free breathing in under 5 min, and was found to be 5 to 6% for healthy volunteers. Magn Reson Med 79:2693–2701, 2018. © 2017 International Society for Magnetic Resonance in Medicine.
Vaginal mesh repair SYSTEMS for pelvic organ prolapse: Anatomical study comparing transobturator/trangluteal versus single incision techniques
Authors: Campagna Giuseppe , Panico Giovanni , Morciano Andrea , Gadonneix Pierre , Delmas Vincent , Cervigni Mauro , Ercoli Alfredo , Scambia Giovanni 
Published: September 2017

IntroductionThe present study aim to compare the anatomic landmarks of two pelvic floor repair systems, in order to identify the potential neurovascular lesions related to different mesh fixation techniques.MethodsAbdominal and perineal dissections of 10 fresh cadavers after prolapse surgery using transobturator/transgluteal versus single incision techniques. Neuro‐vascular structures of obturator region and perineum were isolated. Distances between needles and anatomical structures were measured.ResultsDuring transobturator anterior repair, the superficial cannula passed 2.5 ± 0.6 cm medially to the obturator canal. The distance of superficial arm to the anterior obturator vessels was 2.2 ± 0.4 cm. The distance of deep cannula to the posterior obturator vessels branches was 1.3 ± 0.5 cm. In two of these cases we observed a lesion of posterior obturator vessels. During single incision repair the distance between the obturator canal and the superficial arms was 2.3 ± 0.7. The mean distances of superficial arms to the anterior and posterior obturator vessels were, respectively, 2.3 ± 0.5 cm and 3.2 ± 0.7 cm. During transgluteal posterior repair the distance between the cannula guide and the ischial spine was 1.7 ± 0.5 cm while it measured 2.3 ± 0.4 cm when single incision posterior device was placed.ConclusionsAnterior transobturator system presents an increased risk of posterior obturator vessels branches injury. During posterior transgluteal repair the distance of the ischio‐anal fossa to sacrospinous ligament represents a way that could rule against the correct needle positioning with increased risk of pudendal lesions. Single incision approach offers an easier access to the sacrospinous ligament with lower risk of pudendal lesions.
Diastolic Blood Pressure Rises with the Exacerbation of Obstructive Sleep Apnea in Males
Authors: Hu Wei , Jin Xian , Chen Chengjun , Zhang Peng , Li Dandan , Su Qian , Yin Guizhi , Hang Yanwen 
Published: September 2017

ObjectiveTo characterize the association pattern between blood pressure (BP), metabolism changes, and obstructive sleep apnea (OSA) severity within male OSA patients.MethodsThe association between systolic BP (SBP), diastolic BP (DBP), glucose, lipids, apnea‐hypopnea index (AHI), oxygen desaturation index (ODI), and arousal index (ArI) was evaluated after adjustment for BMI and waist circumference/hip circumference ratio (WHR) in 1,370 male OSA patients.ResultsIn the multiple linear regression models using SBP as an independent variable, SBP did not associate with the increase of any OSA indexes. BMI and glucose positively associated with AHI, ODI, and ArI elevation. WHR was also positively associated with increasing AHI and ODI. Total cholesterol levels increased with ODI and ArI increases. Triglyceride was associated with ArI. In the multiple linear regression models using DBP as an independent variable, DBP associated universally with AHI, ODI, and ArI with stable coefficients ranging from 0.19 to 0.20. The remaining independent variables were associated with AHI, ODI, and ArI with a similar trend to the models including SBP as an independent variable.ConclusionsApnea‐hypopnea, hypoxemia, and arousal changed glycometabolism, fat metabolism, and BP profoundly in a particular pattern.
Preliminary evidence supports circulating microRNAs as prognostic biomarkers for type 2 diabetes
Authors: Flowers E. , Kanaya A. M. , Fukuoka Y. , Allen I. E. , Cooper B. , Aouizerat B. E. 
Published: September 2017

SummaryBackgroundCirculating microRNAs are emerging as potential prognostic biomarkers for the development of type 2 diabetes. However, microRNAs are also associated with complications from impaired glucose metabolism (e.g. endothelial cell function). Prior studies have not evaluated for associations between trajectories of circulating microRNAs with trajectories of fasting blood glucose over time and the responses to behavioral interventions to reduce risk. This study performed longitudinal assessment of microRNAs and fasting blood glucose and identified relationships between microRNAs and behavioral risk reduction interventions.MethodsMicroRNAs (n = 353) were measured in subsets (n = 10, n = 8) of participants from previously completed clinical trials that studied behavioral risk reduction interventions. Fasting blood glucose trajectories were associated with changes in 45 microRNAs over 12 months.ResultsFollowing a 3‐month physical activity and dietary intervention compared with baseline, 13 microRNAs were differentially expressed. Seven microRNAs (i.e. miR‐106b, miR‐20b, miR‐363, miR‐486, miR‐532, miR‐92a and miR‐93) were commonly identified between the two analyses.ConclusionsFurther studies are needed to determine which microRNAs are prognostic biomarkers of risk for type 2 diabetes versus consequences of impaired glucose metabolism. Additional future directions of this research are to differentiate whether microRNAs are prognostic and/or diagnostic biomarkers for risk for type 2 diabetes and predictive biomarkers of responses to risk reduction interventions.
Utility of the immature platelet fraction in pediatric immune thrombocytopenia: Differentiating from bone marrow failure and predicting bleeding risk
Authors: McDonnell Alicia , Bride Karen L. , Lim Derick , Paessler Michele , Witmer Char M. , Lambert Michele P. 
Published: September 2017

AbstractBackgroundDifferentiating childhood immune thrombocytopenia (ITP) from other cause of thrombocytopenia remains a diagnosis of exclusion. Additionally factors that predict bleeding risk for those patients with ITP are currently not well understood. Previous small studies have suggested that immature platelet fraction (IPF) may differentiate ITP from other causes of thrombocytopenia and in combination with other factors may predict bleeding risk.MethodsWe performed a retrospective chart review of thrombocytopenic patients with an IPF measured between November 1, 2013 and July 1, 2015. Patients were between 2 months and 21 years of age with a platelet count <50 × 109/l. Each patient chart was reviewed for final diagnosis and bleeding symptoms. A bleeding severity score was retrospectively assigned.ResultsTwo hundred seventy two patients met inclusion criteria, 97 with ITP, 11 with bone marrow failure (BMF), 126 with malignancy, and 38 with other causes of thrombocytopenia. An IPF > 5.2% differentiated ITP from BMF with 93% sensitivity and 91% specificity. Absolute immature platelet number (AIPN) was significantly lower in ITP patients with severe to life‐threatening hemorrhage than those without, despite similar platelet counts. On multivariate analysis, an IPF < 10.4% was confirmed as an independent predictor of bleeding risk at platelet counts <10 × 109/l in patients with ITP.ConclusionsIPF measurement alone has utility in both the diagnosis of ITP and identifying patients at increased risk of hemorrhage. Further study is required to understand the pathophysiological differences of ITP patients with lower IPF/AIPN.
Initial testing (stage 1) of M6620 (formerly VX‐970), a novel ATR inhibitor, alone and combined with cisplatin and melphalan, by the Pediatric Preclinical Testing Program
Authors: Kurmasheva Raushan T. , Kurmashev Dias , Reynolds C. Patrick , Kang Min , Wu Jianwrong , Houghton Peter J. , Smith Malcolm A. 
Published: September 2017

AbstractBackgroundM6620 is a novel inhibitor of the DNA damage repair enzyme ATR, and has potentiated the activity of cisplatin and irinotecan in non‐small cell lung cancer and colon cancer xenografts, respectively.ProceduresM6620 was tested in vitro at concentrations ranging from 1.0 nM to 10.0 μM and at 75 nM in combination with cisplatin or melphalan. M6620 was tested against 24 solid tumor xenografts alone and in combination with cisplatin. Cisplatin was administered intraperitoneally on days 1 and 8 at a dose of 5 mg/kg. M6620 was administered intravenously on days 2 and 9 at 20 mg/m2 approximately 16 hr after cisplatin.ResultsThe median relative IC50 (rIC50) value for M6620 was 0.19 μM (range 0.03–1.38 μM). M6620 reduced the mean IC50 of cisplatin and melphalan by 1.48‐ and 1.95‐fold, respectively. M6620 as a single agent in vivo induced significant differences in event‐free survival (EFS) distribution in 5 of 24 (21%) solid tumor xenografts, but induced no objective responses. Cisplatin as a single agent induced significant differences in EFS distribution compared to control in 18 of 24 (75%) solid tumor xenografts. Three objective responses to cisplatin were observed. The M6620 and cisplatin combination induced significant differences in EFS distribution compared to control in 21 of 24 (88%), with four objective responses.ConclusionsM6620 showed modest potentiation of cisplatin and melphalan activity for some cell lines. M6620 showed little single‐agent activity and the addition of M6620 to cisplatin significantly prolonged time to event for a minority of tested xenografts across several histologies.
A novel approach using long‐read sequencing and ddPCR to investigate gonadal mosaicism and estimate recurrence risk in two families with developmental disorders
Authors: Wilbe Maria , Gudmundsson Sanna , Johansson Josefin , Ameur Adam , Stattin Eva‐Lena , Annerén Göran , Malmgren Helena , Frykholm Carina , Bondeson Marie‐Louise 
Published: September 2017

AbstractObjectiveDe novo mutations contribute significantly to severe early‐onset genetic disorders. Even if the mutation is apparently de novo, there is a recurrence risk due to parental germ line mosaicism, depending on in which gonadal generation the mutation occurred.MethodsWe demonstrate the power of using SMRT sequencing and ddPCR to determine parental origin and allele frequencies of de novo mutations in germ cells in two families whom had undergone assisted reproduction.ResultsIn the first family, a TCOF1 variant c.3156C>T was identified in the proband with Treacher Collins syndrome. The variant affects splicing and was determined to be of paternal origin. It was present in <1% of the paternal germ cells, suggesting a very low recurrence risk. In the second family, the couple had undergone several unsuccessful pregnancies where a de novo mutation PTPN11 c.923A>C causing Noonan syndrome was identified. The variant was present in 40% of the paternal germ cells suggesting a high recurrence risk.ConclusionsOur findings highlight a successful strategy to identify the parental origin of mutations and to investigate the recurrence risk in couples that have undergone assisted reproduction with an unknown donor or in couples with gonadal mosaicism that will undergo preimplantation genetic diagnosis.