bluuebunny/crossref_metadata_2025_split huggingface dataset:
Can we predict subject‐specific dynamic cortical thickness maps during infancy from birth?
Authors: Meng Yu , Li Gang , Rekik Islem , Zhang Han , Gao Yaozong , Lin Weili , Shen Dinggang 
Published: March 2017

AbstractUnderstanding the early dynamic development of the human cerebral cortex remains a challenging problem. Cortical thickness, as one of the most important morphological attributes of the cerebral cortex, is a sensitive indicator for both normal neurodevelopment and neuropsychiatric disorders, but its early postnatal development remains largely unexplored. In this study, we investigate a key question in neurodevelopmental science: can we predict the future dynamic development of cortical thickness map in an individual infant based on its available MRI data at birth? If this is possible, we might be able to better model and understand the early brain development and also early detect abnormal brain development during infancy. To this end, we develop a novel learning‐based method, called Dynamically‐Assembled Regression Forest (DARF), to predict the development of the cortical thickness map during the first postnatal year, based on neonatal MRI features. We applied our method to 15 healthy infants and predicted their cortical thickness maps at 3, 6, 9, and 12 months of age, with respectively mean absolute errors of 0.209 mm, 0.332 mm, 0.340 mm, and 0.321 mm. Moreover, we found that the prediction precision is region‐specific, with high precision in the unimodal cortex and relatively low precision in the high‐order association cortex, which may be associated with their differential developmental patterns. Additional experiments also suggest that using more early time points for prediction can further significantly improve the prediction accuracy. Hum Brain Mapp 38:2865–2874, 2017. © 2017 Wiley Periodicals, Inc.
Functional organization of the human posterior cingulate cortex, revealed by multiple connectivity‐based parcellation methods
Authors: Cha Jungho , Jo Hang Joon , Gibson William S. , Lee Jong‐Min 
Published: March 2017

AbstractBased on cytoarchitecture, the posterior cingulate cortex (PCC) is thought to be comprised of two distinct functional subregions: the dorsal and ventral PCC (dPCC and vPCC). However, functional subregions do not completely match anatomical boundaries in the human brain. To understand the relationship between the functional organization of regions and anatomical features, it is necessary to apply parcellation algorithms based on functional properties. We therefore defined functionally informed subregions in the human PCC by parcellation of regions with similar patterns of functional connectivity in the resting brain. We used various patterns of functional connectivity, namely local, whole‐brain and diffuse functional connections of the PCC, and various clustering methods, namely hierarchical, spectral, andk‐means clustering to investigate the subregions of the PCC. Overall, the approximate anatomical boundaries and predicted functional regions were highly overlapped to each other. Using hierarchical clustering, the PCC could be clearly separated into two anatomical subregions, namely the dPCC and vPCC, and further divided into four subregions segregated by local functional connectivity patterns. We show that the PCC could be separated into two (dPCC and vPCC) or four subregions based on local functional connections and hierarchical clustering, and that subregions of PCC display differential global functional connectivity, particularly along the dorsal‐ventral axis. These results suggest that differences in functional connectivity between dPCC and vPCC may be due to differences in local connectivity between these functionally hierarchical subregions of the PCC.Hum Brain Mapp 38:2808–2818, 2017. ©2017 Wiley Periodicals, Inc.
Genital Mycoplasma infection among Mexican women with systemic lupus erythematosus
Authors: Méndez‐Martínez Socorro , García‐Carrasco Mario , Cedillo‐Ramírez María L. , Mendoza‐Pinto Claudia , Etchegaray‐Morales Ivet , Gil‐Juárez Constantino , Montiel‐Jarquín Álvaro J. , Taboada‐Cole Alejandro , Jiménez‐Herrera Erick A. , Muñóz‐Guarneros Margarita , Cervera Ricard 
Published: March 2017

AbstractObjectiveTo assess the prevalence of genital Mycoplasma spp. among women with systemic lupus erythematosus (SLE) and to identify factors associated with such infection.MethodsA cross‐sectional study was conducted among patients with SLE and healthy women who attended a hospital in Puebla, Mexico, between July 29, 2014, and January 4, 2015. All participants were aged 18 years or older and sexually active. A structured interview assessed sociodemographic, obstetric, gynecologic, and clinical characteristics. Disease activity was evaluated using the Mexican SLE Disease Activity Index. Polymerase chain reaction was used to detect the presence of Mycoplasma spp. in genital samples.ResultsUreaplasma urealyticum was the only genital mycoplasma detected; it was present in 32 (24.6%) of 130 patients with SLE and 12 (12.8%) of 94 healthy women. Patients with SLE had increased odds of infection (odds ratio 2.120, 95% confidence interval 1.046–4.296). Among patients with SLE, multiparity was more common in those with U. urealyticum infection (P=0.043).ConclusionOne‐quarter of women with SLE had genital infection with U. urealyticum. An association was found between infection and multiparity among women with SLE.
The Estimation of Second-Generation HR-pQCT From First-Generation HR-pQCT Using In Vivo Cross-Calibration
Authors: Manske Sarah L , Davison Erin M , Burt Lauren A , Raymond Duncan A , Boyd Steven K 
Published: March 2017

ABSTRACT

Second-generation high-resolution peripheral quantitative computed tomography (HR-pQCT) provides the highest resolution in vivo to assess bone density and microarchitecture in 3D. Although strong agreement of most outcomes measured with first- (XCTI) and second- (XCTII) generation HR-pQCT has been demonstrated, the ability to use the two systems interchangeably is unknown. From in vivo measurements, we determined the limits of estimating XCTII data from XCTI scans conducted in vivo and whether that estimation can be improved by linear cross-calibration equations. These data are crucial as the research field transitions to the new technology. Our study design established cross-calibration equations by scanning 62 individuals on both systems on the same day and then tested those cross-calibrations on the same cohort 6 months later so that estimated (denoted as XCTII*) and “true” XCTII parameters could be compared. We calculated the generalized least-significant change (GLSC) for those predictions. There was strong agreement between both systems for density (R2 &gt; 0.94), macroarchitecture (R2 &gt; 0.95), and most microarchitecture outcomes with the exception of trabecular thickness (Tb.Th, R2 = 0.51 to 0.67). Linear regression equations largely eliminated the systematic error between XCTII and XCTII* and produced a good estimation of most outcomes, with individual error estimates between 0.2% and 3.4%, with the exception of Tt.BMD. Between-system GLSC was similar to within-XCTI LSC (eg, 8.3 to 41.9 mg HA/cm3 for density outcomes). We found that differences between outcomes assessed with XCTI and XCTII can be largely eliminated by cross-calibration. Tb.Th is poorly estimated because it is measured more accurately by XCTII than XCTI. It may be possible to use cross-calibration for most outcomes when both scanner generations are used for multicenter and longitudinal studies. © 2017 American Society for Bone and Mineral Research.
In situ and post‐synthesis immobilization of enzymes on nanocrystalline MOF platforms to yield active biocatalysts
Authors: Gascón Victoria , Castro‐Miguel Elsa , Díaz‐García Manuel , Blanco Rosa M , Sanchez‐Sanchez Manuel 
Published: March 2017

AbstractBACKGROUNDVery recently, metal‐organic framework (MOF) materials have been postulated as emerging supports to achieve solid‐state enzyme‐contained biocatalysts. In this work, post‐synthesis and in situ strategies to immobilize β‐glucosidase and laccase on different MOF materials were studied. The MOF‐based supports, i.e. MIL‐53(Al), NH2‐MIL‐53(Al) and Mg‐MOF‐74, were prepared under soft and sustainable conditions (room temperature and pH values compatible with enzymatic activity), allowing development of the in situ strategy.RESULTSIn both post‐synthesis and in situ approaches, the intercrystalline mesoporosity of the MOF‐based support favored the immobilization efficiency or the specific activity. The latter expressed as units per milligram of immobilized enzyme was higher in the post‐synthesis immobilization, whereas the biocatalysts prepared in situ gave much higher enzyme loading (over 85%) and lower enzyme leaching (around 5%). The in situ approach even worked in a non‐aqueous (N,N‐dimethylformamide) media in which the free enzyme was completely inactive. The immobilized enzymes are much larger than the structural pores of the MOFs.CONCLUSIONSEnzymes can be efficiently immobilized on nanocrystalline MOFs prepared under soft and sustainable conditions despite the supports lacking large enough pores to host the enzymes. The in situ approach is very efficient capturing enzymes and preserving some of their activity even under adverse conditions. © 2017 Society of Chemical Industry
Diffusion tensor imaging MR neurography for the detection of polyneuropathy in type 1 diabetes
Authors: Vaeggemose Michael , Pham Mirko , Ringgaard Steffen , Tankisi Hatice , Ejskjaer Niels , Heiland Sabine , Poulsen Per L. , Andersen Henning 
Published: March 2017

PurposeTo evaluate if diffusion tensor imaging MR neurography (DTI‐MRN) can detect lesions of peripheral nerves in patients with type 1 diabetes.Materials and MethodsEleven type 1 diabetic patients with polyneuropathy (DPN), 10 type 1 diabetic patients without polyneuropathy (nDPN), and 10 healthy controls (HC) were investigated with a 3T MRI scanner. Clinical examinations, nerve‐conduction studies, and vibratory‐perception thresholds determined the presence of DPN. DTI‐MRN (voxel size: 1.4 × 1.4 × 3 mm3; b‐values: 0, 800 s/mm2) covered proximal (sciatic nerve) and distal regions of the lower extremity (tibial nerve). Fractional anisotropy (FA) and apparent diffusion coefficient (ADC) were calculated and compared to T2‐relaxometry and proton‐spin density obtained from a multiecho turbo spin echo (TSE) sequence. Furthermore, we evaluated DTI reproducibility, repeatability, and diagnostic accuracy.ResultsDTI‐MRN could accurately discriminate between DPN, nDPN, and HC. The proximal FA was lowest in DPN (DPN 0.37 ± 0.06; nDPN 0.47 ± 0.03; HC 0.49 ± 0.06; P < 0.01). In addition, distal FA was lowest in DPN (DPN 0.31 ± 0.05; nDPN 0.41 ± 0.07; HC 0.43 ± 0.08; P < 0.01). Likewise, proximal ADC was highest in DPN (DPN 1.69 ± 0.25 × 10−3mm2/s; nDPN 1.50 ± 0.06 × 10−3mm2/s; HC 1.42 ± 0.12 × 10−3mm2/s; P < 0.01) as was distal ADC (DPN 1.87 ± 0.45 × 10−3mm2/s; nDPN 1.59 ± 0.19 × 10−3mm2/s; HC 1.57 ± 0.26 × 10−3mm2/s; P = 0.09). The combined interclass‐correlation (ICC) coefficient of DTI reproducibility and repeatability was high in the sciatic nerve (ICC: FA = 0.86; ADC = 0.85) and the tibial nerve (ICC: FA = 0.78; ADC = 0.66). T2‐relaxometry and proton‐spin‐density did not enable detection of neuropathy.ConclusionDTI‐MRN accurately detects DPN by lower nerve FA and higher ADC. These alterations are likely to reflect proximal and distal nerve fiber pathology.Level of Evidence: 1J. Magn. Reson. Imaging 2017;45:1125–1134
Aligned Poly(ε‐caprolactone) Nanofibers Guide the Orientation and Migration of Human Pluripotent Stem Cell‐Derived Neurons, Astrocytes, and Oligodendrocyte Precursor Cells In Vitro
Authors: Hyysalo Anu , Ristola Mervi , Joki Tiina , Honkanen Mari , Vippola Minnamari , Narkilahti Susanna 
Published: March 2017

Stem cell transplantations for spinal cord injury (SCI) have been studied extensively for the past decade in order to replace the damaged tissue with human pluripotent stem cell (hPSC)‐derived neural cells. Transplanted cells may, however, benefit from supporting and guiding structures or scaffolds in order to remain viable and integrate into the host tissue. Biomaterials can be used as supporting scaffolds, as they mimic the characteristics of the natural cellular environment. In this study, hPSC‐derived neurons, astrocytes, and oligodendrocyte precursor cells (OPCs) are cultured on aligned poly(ε‐caprolactone) nanofiber platforms, which guide cell orientation to resemble that of spinal cord in vivo. All cell types are shown to efficiently spread over the nanofiber platform and orient according to the fiber alignment. Human neurons and astrocytes require extracellular matrix molecule coating for the nanofibers, but OPCs grow on nanofibers without additional treatment. Furthermore, the nanofiber platform is combined with a 3D hydrogel scaffold with controlled thickness, and nanofiber‐mediated orientation of hPSC‐derived neurons is also demonstrated in a 3D environment. In this work, clinically relevant materials and substrates for nanofibers, fiber coatings, and hydrogel scaffolds are used and combined with cells suitable for developing functional cell grafts for SCI repair.
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Synthesis of Activated Ester Functional Polyesters through Light‐Induced [4+4] Cycloaddition Polymerization
Authors: Baysak Elif , Durmaz Hakan , Tunca Umit , Hizal Gurkan 
Published: March 2017

A combination of light‐induced [4+4] cycloaddition polymerization and activated ester substitution reaction is demonstrated as a new method to obtain novel polymeric structures. Bis‐anthracene functionalized compound involving perfluorophenyl ester moiety namely, bisanthracenyl‐PFPE, is prepared by an esterification reaction, then polymerized under UV light irradiated at 365 nm. The resulting polymer is reacted with a variety of amine compounds namely allylamine, benzylamine, furfurylamine, and propargylamine, under mild conditions. Quantitative conversions of perfluorophenyl ester groups into the respective amide groups as well as the thermal behaviors of all polymers are revealed by using various spectroscopic measurements such as Fourier transform infrared spectroscopy (FT‐IR), gel permeation chromatography, NMR, and differential scanning calorimetry.
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Cross‐Linking Dynamics of Cellulose Nanofibrils‐Based Transient Network Hydrogels: A Study of pH Dependence
Authors: Yin Aishu , Yang Jun 
Published: March 2017

Interactions between polymer chains and nanoparticles can play a dominant role in composites mechanics, yet the control of such interfacial dynamics is still a significant challenge. This paper reports the effect of pH on cellulose nanofibrils (CNFs) transient hydrogels network mechanics via interfacial ionic cross‐linking bonds. For this purpose, carboxylated CNFs are incorporated with amine groups terminated 8‐arm poly(ethylene glycol) (PEG‐NH2) to assemble the first noncovalent network via reversible ionic interactions at the CNF surfaces, where the end‐group acrylate modified linear difunctional PEG forms the second lightly covalent cross‐linked network. The viscoelastic properties of the supramolecular gels are examined as a function of pH, and the unique transient mechanics resulting from CNF‐PEG complexation structures show that the processing from acidic‐to‐alkaline pH change leads to the gel cross‐links transition from covalent type to covalent–noncovalent hybrid one. This finding offers an alternative way to tune CNF gels mechanical reinforcement and sheds light on the pH dependence of network architectural changes.image
Nitric oxide‐enhanced Shiga toxin production was regulated by Fur and RecA in enterohemorrhagic Escherichia coli O157
Authors: Ichimura Kimitoshi , Shimizu Takeshi , Matsumoto Akio , Hirai Shinichiro , Yokoyama Eiji , Takeuchi Hiroki , Yahiro Kinnosuke , Noda Masatoshi 
Published: March 2017

AbstractEnterohemorrhagic Escherichia coli (EHEC) produces Shiga toxin 1 (Stx1) and Shiga toxin 2 (Stx2). Nitric oxide (NO), which acts as an antimicrobial defense molecule, was found to enhance the production of Stx1 and Stx2 in EHEC under anaerobic conditions. Although EHEC O157 has two types of anaerobic NO reductase genes, an intact norV and a deleted norV, in the deleted norV‐type EHEC, a high concentration of NO (12–29 μmol/L, maximum steady‐state concentration) is required for enhanced Stx1 production and a low concentration of NO (~12 μmol/L, maximum steady‐state concentration) is sufficient for enhanced Stx2 production under anaerobic conditions. These results suggested that different concentration thresholds of NO elicit a discrete set of Stx1 and Stx2 production pathways. Moreover, the enhancement of Shiga toxin production in the intact norV‐type EHEC required treatment with a higher concentration of NO than was required for enhancement of Shiga toxin production in the deleted norV‐type EHEC, suggesting that the specific NorV type plays an important role in the level of enhancement of Shiga toxin production in response to NO. Finally, Fur derepression and RecA activation in EHEC were shown to participate in the NO‐enhanced Stx1 and Stx2 production, respectively.
Optimized Metallization for Interdigitated Back Contact Silicon Heterojunction Solar Cells
Authors: Stang Johann‐Christoph , Franssen Thijs , Haschke Jan , Mews Mathias , Merkle Agnes , Peibst Robby , Rech Bernd , Korte Lars 
Published: March 2017

We report on the design and manufacturing of interdigitated back contact cells based on the silicon heterojunction technology. The influence of geometry and overlap of the doped amorphous silicon layers forming the contact fingers on device performance have been investigated by simulation. Two contact formation concepts, with and without a TCO interlayer – an indium tin oxide/silver (ITO/Ag) stack, and a direct aluminum (Al) metallization – are experimentally evaluated. The former retains good passivation but leads to a too high contact resistivity, the latter shows the opposite behavior, but yields a slight benefit in terms of overall performance achieving more than 20% of efficiency. We show that in this case a contact system is formed whose properties can be tuned by annealing, enabling a trade‐off between VOC and FF.Structure of the presented solar cell; a SiNX layer covers the front side, the rear side is passivated by overlapping layer stacks of intrinsic and doped amorphous silicon, the latter are contacted by aluminum.
Sauropod tooth morphotypes from the Upper Jurassic of the Lusitanian Basin (Portugal)
Authors: Mocho Pedro , Royo‐Torres Rafael , Malafaia Elisabete , Escaso Fernando , Ortega Francisco 
Published: March 2017

AbstractThe Upper Jurassic of the Lusitanian Basin has yielded an important fossil record of sauropods, but little information is available about the tooth morphotypes represented in this region. A large sample of teeth, both unpublished and published, is described and discussed here. Four main tooth morphologies are identified: spatulate, heart‐shaped, pencil‐shaped, and compressed cone‐chisel‐shaped. Heart‐shaped teeth are considered to be exclusive to a non‐neosauropod eusauropod, tentatively referred to Turiasauria. The spatulate teeth can be attributed to members of the Macronaria; they have a complex cingulum, more than one lingual facet and a labial ridge. The compressed cone‐chisel‐shaped teeth are also attributed to macronarians and the presence of an axially twisted apex through an arc of 30°–45° suggests putative affinities withEuropasaurusand basal titanosauriforms. The variability observed in the overall morphology and wrinkling pattern of the compressed cone‐chisel‐shaped teeth may be due to factors related to the tooth position or to the ontogeny of individuals. Finally, pencil‐shaped teeth with high slenderness index values, oval and apically located wear facets, subcylindrical crowns and lacking carinae, are tentatively assigned to Diplodocoidea. The diversity of tooth morphologies is in accordance with the known palaeobiodiversity of the Portuguese Late Jurassic sauropod fauna, which is composed of non‐neosauropod eusauropods (turiasaurs), diplodocoids (diplodocids) and macronarians (camarasaurids and probably brachiosaurids). The Late Jurassic sauropod fossil record of the Iberian Peninsula presents the broadest tooth morphospace range in the world from this period, suggesting a wide niche partition for sauropods, and corresponding high taxonomic diversity.
A Population‐Based Cohort Study of Emergency Appendectomy Performed in England and New York State
Authors: Al‐Khyatt Waleed , Mytton Jemma , Tan Benjamin H. L. , Aquina Christopher T. , Evison Felicity , Fleming Fergal J. , Pasquali Sandro , Griffiths Ewen A. , Vohra Ravinder S. 
Published: March 2017

AbstractBackgroundTo compare selected outcomes (30‐day reoperation and total length of hospital stay) following emergency appendectomy between populations from New York State and England.MethodsThis retrospective cohort study used demographic and in‐hospital outcome data from Hospital Episode Statistics (HES) and the New York Statewide Planning and Research Cooperative System (SPARCS) administrative databases for all patients aged 18+ years undergoing appendectomy between April 2009 and March 2014. Univariate and adjusted multivariable logistic regression were used to test significant factors. A one‐to‐one propensity score matched dataset was created to compare odd ratios (OR) of reoperations between the two populations.ResultsA total of 188,418 patient records, 121,428 (64.4%) from England and 66,990 (35.6%) from NYS, were extracted. Appendectomy was completed laparoscopically in 77.7% of patients in New York State compared to 53.6% in England (P < 0.001). The median lengths of hospital stay for patients undergoing appendectomy were 3 (interquartile range, IQR 2–4) days versus 2 (IQR 1–3) days (P < 0.001) in England and New York State, respectively. All 30‐day reoperation rates were higher in England compared to New York State (1.2 vs. 0.6%, P < 0.001), representing nearly a twofold higher risk of 30‐day reoperation (OR 1.88, 95% CI 1.64–2.14, P < 0.001). As the proportion of appendectomy completed laparoscopically increased, there was a reduction in the reoperation rate in England (correlation coefficient −0.170, P = 0.036).ConclusionsReoperations and total length of hospital stay is significantly higher following appendectomy in England compared to New York State. Increasing the numbers of appendectomy completed laparoscopically may decrease length of stay and reoperations.