bluuebunny/crossref_metadata_2025_split huggingface dataset:
Yields and Characterization of Dissolved Organic Matter From Different Aged Soils in Northern Alaska
Authors: Gao Lei , Zhou Zhengzhen , Reyes Alberto V. , Guo Laodong 
Published: June 2018

AbstractSoil organic matter (SOM) in northern high‐latitude regions is a major component of the global carbon cycle. However, the yield of soil‐dissolved organic matter (DOM) during soil‐water interactions and its chemical characteristics and reactivities remain poorly understood. We report here elemental composition and isotopic signatures of bulk‐SOM from northern Alaska, and yields of water‐leachable soil‐DOM, including dissolved organic carbon, dissolved organic nitrogen, and dissolved organic phosphorus, and nutrients (dissolved inorganic nitrogen and phosphate). The bulk‐SOM contained 5,400–373,900 μg‐C/g‐soil, 500–12,610 μg‐N/g‐soil, and 38.6–384 μg‐P/g‐soil, with a C/N ratio of 13–37 and a C/P ratio of 80–3,911. The water‐extractable dissolved organic carbon, dissolved organic nitrogen, and dissolved organic phosphorus only accounted for 0.58–2.5%, 0.91–3.4%, and 1.2–3.0% of their corresponding total soil‐OC, N, and OP, respectively. While SOM‐δ13C was less variable (−27.08‰ to −26.49‰) showing the same overall C source, 14C‐ages varied widely from 1,170 ± 20 to 16,200 ± 55 years before present, indicating different deposition‐conditions and subsequent‐processes among the soil samples. The specific‐UV‐absorbance at 254 nm (or aromaticity) of soil‐DOM differed considerably and was negatively correlated to spectral slope values. A humic‐like (C1), a low‐molecular‐weight fulvic‐like (C2), and a protein‐like component (C3) were identified as the major fluorescent‐DOM components. The C3/C2 and C3/C1 ratios generally increased with SOM‐14C‐age, suggesting a preferential degradation/transformation of humic‐like and fulvic‐like components or a transformation/production of protein‐like components within permafrost. Both biological and humification indices increased with 14C‐age, excluding the oldest soil, which pointed to a preferential preservation or transformation/production of protein‐like DOM within permafrost, implying that soil‐DOM derived from old permafrost can be highly vulnerable and readily decomposed upon permafrost thaw.
Succinate induces aberrant mitochondrial fission in cardiomyocytes through GPR91 signaling
Authors: Lu Yi-Tong , Li Lan-Zhu , Yang Yi-Lin , Yin Xiaojian , Liu Qun , Zhang Lei , Liu Kang , Liu Baolin , Li Jia , Qi Lian-Wen 
Published: June 2018

AbstractAltered mitochondrial metabolism acts as an initial cause for cardiovascular diseases and metabolic intermediate succinate emerges as a mediator of mitochondrial dysfunction. This work aims to investigate whether or not extracellular succinate accumulation and its targeted G protein-coupled receptor-91 (GPR91) activation induce cardiac injury through mitochondrial impairment. The results showed that extracellular succinate promoted the translocation of dynamin-related protein 1 (Drp1) to mitochondria via protein kinase Cδ (PKCδ) activation, and induced mitochondrial fission factor (MFF) phosphorylation via extracellular signal-regulated kinases-1/2 (ERK1/2) activation in a GPR91-dependent manner. As a result, enhanced localization of MFF and Drp1 in mitochondria promoted mitochondrial fission, leading to mitochondrial dysfunction and cardiomyocyte apoptosis. We further showed that inhibition of succinate release and GPR91 signaling ameliorated oxygen–glucose deprivation-induced injury in cardiomyocytes and isoproterenol-induced myocardial ischemia injury in mice. Taken together, these results showed that in response to cardiac ischemia, succinate release activated GPR91 and induced mitochondrial fission via regulation of PKCδ and ERK1/2 signaling branches. These findings suggest that inhibition of extracellular succinate-mediated GPR91 activation might be a potential therapeutic strategy for protecting cardiomyocytes from ischemic injury.
Individuality and convergence of the infant gut microbiota during the first year of life
Authors: de Muinck Eric J. , Trosvik Pål 
Published: June 2018

AbstractThe human gut microbiota plays a vital role in health and disease, and microbial colonization is a key process in infant development. Here, we analyze 2684 fecal specimens from 12 infants during their first year of life, providing detailed insights into the human gut colonization process. Maturation of the gut microbial community shows strong temporal structure and specific developmental stages. At 2–4 months of age, there is a period of accelerated convergence concurrent with a bloom ofBifidobacterium, a genus associated with metabolism of oligosaccharides found in breast milk. The end of this period coincides with the introduction of solid food, a reduction in the relative abundance ofBifidobacterium, and an increase in several groups of Firmicutes. Our findings highlight the dynamic nature and individuality of the gut colonization process, and the need for high-frequency sampling over an extended period when designing and interpreting infant microbiome studies.
Topologically frustrated dynamics of crowded charged macromolecules in charged hydrogels
Authors: Jia Di , Muthukumar Murugappan 
Published: June 2018

AbstractMovement of charged macromolecules in crowded aqueous environments is a ubiquitous phenomenon vital to the various living processes and formulations of materials for health care. While study of diffusion of tracer amounts of probe macromolecules trapped inside concentrated solutions, gels, or random media has led to an enhanced understanding of this complex process, the collective dynamics of charged macromolecules embedded inside congested charge-bearing matrices still remains to be fully explored. Here we report a frustrated dynamics of DNA and synthetic polyelectrolytes inside a charged host hydrogel where the guest molecules do not diffuse. Instead, they exhibit a family of relaxation processes arising from a combination of conformational entropy and local chain dynamics, which are frustrated by the confinement from the gel. We also have developed a model explaining this new universality class of non-diffusive topologically frustrated dynamics of charged macromolecules.
In vivo detection of nanometer-scale structural changes of the human tympanic membrane in otitis media
Authors: Dsouza Roshan , Won Jungeun , Monroy Guillermo L. , Hill Malcolm C. , Porter Ryan G. , Novak Michael A. , Boppart Stephen A. 
Published: June 2018

AbstractOtitis media (OM) is a common ear infection and a leading cause of conductive hearing loss in the pediatric population. Current technologies such as otoscopy, pneumatic otoscopy, tympanometry, and acoustic reflectometry are used to diagnose OM, which can reasonably diagnose the infection with a sensitivity and specificity of 50–90% and 60–90%, respectively. However, these techniques provide limited information about the physical architecture of the tympanic membrane (TM), or what may lie behind it. Here, we report the detection of nanometer-scale structural changes of the TM using nano-sensitive optical coherence tomography (nsOCT). In total, an image dataset from 65 pediatric subjects from three different groups (normal, acute OM, and chronic OM) and with longitudinal image-based analysis of ear infections were included in this study. The nsOCT data were correlated with physician diagnosis and with OCT thickness measurements and were found to be in good agreement with these results. We report that nsOCT detects in vivo structural deformations of the TM earlier than OCT alone, and enhances the detection sensitivity of OCT measurements. This unique technique for early detection of nano-scale structural modifications in the TM has the potential to aid in our understanding of microbiological effects, and possibly for early diagnosis and more effective treatment of OM.
Chloroquine and amodiaquine enhance AMPK phosphorylation and improve mitochondrial fragmentation in diabetic tubulopathy
Authors: Jeong Hye Yun , Kang Jun Mo , Jun Hak Hoon , Kim Dong-Jin , Park Seon Hwa , Sung Min Ji , Heo Jin Hyung , Yang Dong Ho , Lee Sang Ho , Lee So-Young 
Published: June 2018

AbstractWe investigated the effects of chloroquine (CQ) and amodiaquine (AQ) on AMPK phosphorylation in renal tubular cells in a diabetic environmentin vivoandin vitro. We also examined whether CQ- or AQ-mediated AMPK activity restoration attenuated diabetic tubulopathy by normalizing mitochondrial fragmentation. Human renal proximal epithelial cells (HKC8) were incubated in high-glucose conditions. Diabetes was induced with streptozotocin in male C57/BL6J mice. Treatment with CQ or AQ abolished high-glucose-induced phospho-AMPK and phosph-PGC1α down-regulation in HKC8 cells. Improvements in functional mitochondrial mass and balanced fusion/fission protein expression were observed in HKC8 cells after treatment with CQ or AQ in high-glucose conditions. Moreover, decreased mitochondrial ROS production and reduced apoptotic and fibrotic protein expression were noted in HKC8 cells after treatment with CQ or AQ, even in high-glucose conditions. CQ and AQ treatment effectively mitigated albuminuria and renal histopathologic changes and increased AMPK activity in the kidneys of diabetic mice. Electron microscopy analysis showed that mitochondrial fragmentation was decreased, and 8-OHdG content was low in the renal tubular cells of the CQ and AQ treatment groups compared with those of the diabetic control group. Our results suggest that CQ and AQ may be useful treatments for patients with diabetic kidney disease.
Control of Spreading Depression with Electrical Fields
Authors: Whalen Andrew J. , Xiao Ying , Kadji Herve , Dahlem Markus A. , Gluckman Bruce J. , Schiff Steven J. 
Published: June 2018

AbstractSpreading depression or depolarization is a large-scale pathological brain phenomenon related to migraine, stroke, hemorrhage and traumatic brain injury. Once initiated, spreading depression propagates across gray matter extruding potassium and other active molecules, collapsing the resting membrane electro-chemical gradient of cells leading to spike inactivation and cellular swelling, and propagates independently of synaptic transmission. We demonstrate the modulation, suppression and prevention of spreading depression utilizing applied transcortical DC electric fields in brain slices, measured with intrinsic optical imaging and potassium dye epifluorescence. We experimentally observe a surface-positive electric field induced forcing of spreading depression propagation to locations in cortex deeper than the unmodulated propagation path, whereby further propagation is confined and arrested even after field termination. The opposite surface-negative electric field polarity produces an increase in propagation velocity and a confinement of the wave to more superficial layers of cortex than the unmodulated propagation path. These field polarities are of opposite sign to the polarity that blocks neuronal spiking and seizures, and are consistent with biophysical models of spreading depression. The results demonstrate the potential feasibility of electrical control and prevention of spreading depression.
Simple, low-cost fabrication of acrylic based droplet microfluidics and its use to generate DNA-coated particles
Authors: Islam Md. Mamunul , Loewen Amanda , Allen Peter B. 
Published: June 2018

AbstractHydrogel microparticles were copolymerized with surface-immobilized DNA. Particles derived from a microfluidic device and particles derived from mechanical homogenization were compared. The hypothesis was tested that a controlled droplet generation mechanism would produce more homogeneous particles. Surprisingly, the DNA content of both particle types was similarly inhomogeneous. To make this test possible, a simple, low cost, and rapid method was developed to fabricate a microfluidic chip for droplet generation and in-line polymerization. This method used a low-cost laser cutter ($400) and direct heat bonding (no adhesives or intermediate layers). The flow focusing droplet generator produced droplets and hydrogel particles 10–200 μm in diameter.
Impact of physical confinement on nuclei geometry and cell division dynamics in 3D spheroids
Authors: Desmaison Annaïck , Guillaume Ludivine , Triclin Sarah , Weiss Pierre , Ducommun Bernard , Lobjois Valérie 
Published: June 2018

AbstractMulticellular tumour spheroids are used as a culture model to reproduce the 3D architecture, proliferation gradient and cell interactions of a tumour micro-domain. However, their 3D characterization at the cell scale remains challenging due to size and cell density issues. In this study, we developed a methodology based on 3D light sheet fluorescence microscopy (LSFM) image analysis and convex hull calculation that allows characterizing the 3D shape and orientation of cell nuclei relative to the spheroid surface. By using this technique and optically cleared spheroids, we found that in freely growing spheroids, nuclei display an elongated shape and are preferentially oriented parallel to the spheroid surface. This geometry is lost when spheroids are grown in conditions of physical confinement. Live 3D LSFM analysis of cell division revealed that confined growth also altered the preferential cell division axis orientation parallel to the spheroid surface and induced prometaphase delay. These results provide key information and parameters that help understanding the impact of physical confinement on cell proliferation within tumour micro-domains.
Mutations in blind cavefish target the light-regulated circadian clock gene, period 2
Authors: Ceinos Rosa Maria , Frigato Elena , Pagano Cristina , Fröhlich Nadine , Negrini Pietro , Cavallari Nicola , Vallone Daniela , Fuselli Silvia , Bertolucci Cristiano , Foulkes Nicholas S. 
Published: June 2018

AbstractLight represents the principal signal driving circadian clock entrainment. However, how light influences the evolution of the clock remains poorly understood. The cavefishPhreatichthys andruzziirepresents a fascinating model to explore how evolution under extreme aphotic conditions shapes the circadian clock, since in this species the clock is unresponsive to light. We have previously demonstrated that loss-of-function mutations targeting non-visual opsins contribute in part to this blind clock phenotype. Here, we have compared orthologs of two core clock genes that play a key role in photic entrainment,cry1aandper2, in both zebrafish andP. andruzzii. We encountered aberrantly spliced variants for theP. andruzzii per2transcript. The most abundant transcript encodes a truncated protein lacking the C-terminal Cry binding domain and incorporating an intronic, transposon-derived coding sequence. We demonstrate that the transposon insertion leads to a predominantly cytoplasmic localization of the cavefish Per2 protein in contrast to the zebrafish ortholog which is distributed in both the nucleus and cytoplasm. Thus, it seems that during evolution in complete darkness, the photic entrainment pathway of the circadian clock has been subject to mutation at multiple levels, extending from opsin photoreceptors to nuclear effectors.
Angiogenesis in human brain tumors: screening of drug response through a patient-specific cell platform for personalized therapy
Authors: Guarnaccia Laura , Navone Stefania Elena , Trombetta Elena , Cordiglieri Chiara , Cherubini Alessandro , Crisà Francesco Maria , Rampini Paolo , Miozzo Monica , Fontana Laura , Caroli Manuela , Locatelli Marco , Riboni Laura , Campanella Rolando , Marfia Giovanni 
Published: June 2018

AbstractGliomas are the most common brain tumors, with diverse biological behaviour. Glioblastoma (GBM), the most aggressive and with the worst prognosis, is characterized by an intense and aberrant angiogenesis, which distinguishes it from low-grade gliomas (LGGs) and benign expansive lesions, as meningiomas (MNGs). With increasing evidence for the importance of vascularization in tumor biology, we focused on the isolation and characterization of endothelial cells (ECs) from primary GBMs, LGGs and MNGs. Gene expression analysis by Real-Time PCR, immunofluorescence and flow cytometry analysis, tube-like structures formation and vascular permeability assays were performed. Our results showed a higher efficiency of ECs to form a complex vascular architecture, as well as a greater impairment of a brain blood barrier model, and an overexpression of pro-angiogenic mediators in GBM than in LGG and MNG. Furthermore, administration of temozolomide, bevacizumab, and sunitinib triggered a different proliferative, apoptotic and angiogenic response, in a dose and time-dependent manner. An increased resistance to temozolomide was observed in T98G cells co-cultured in GBM-EC conditioned media. Therefore, we developed a novel platform to reproduce tumor vascularization as “disease in a dish”, which allows us to perform screening of sensitivity/resistance to drugs, in order to optimize targeted approaches to GBM therapy.
Music playschool enhances children’s linguistic skills
Authors: Linnavalli Tanja , Putkinen Vesa , Lipsanen Jari , Huotilainen Minna , Tervaniemi Mari 
Published: June 2018

AbstractSeveral studies have suggested that intensive musical training enhances children’s linguistic skills. Such training, however, is not available to all children. We studied in a community setting whether a low-cost, weekly music playschool provided to 5–6-year-old children in kindergartens could already affect their linguistic abilities. Children (N = 66) were tested four times over two school-years with Phoneme processing and Vocabulary subtests, along with tests for Perceptual reasoning skills and Inhibitory control. We compared the development of music playschool children to their peers either attending to similarly organized dance lessons or not attending to either activity. Music playschool significantly improved the development of children’s phoneme processing and vocabulary skills. No such improvements on children’s scores for non-verbal reasoning and inhibition were obtained. Our data suggest that even playful group music activities – if attended to for several years – have a positive effect on pre-schoolers’ linguistic skills. Therefore we promote the concept of implementing regular music playschool lessons given by professional teachers in early childhood education.
Wide‐input dynamic range 1 MHz clock ultra‐low supply flip‐flop
Authors: Ramaswami Palaniappan A. , Siek L. 
Published: June 2018

A new wide‐input dynamic range flip‐flop capable of operation at an ultra‐low supply voltage of 0.16 V is presented. The proposed flip‐flop named as capacitively boosted sense‐amplifier flip‐flop (CB‐SAFF) utilises a capacitively boosted sense‐amplifier master stage to sense the data signals and amplify them to a voltage higher than the supply and below the ground for driving the slave latch stage with improved strength. Using the same size of input/output transistors and load capacitance, the proposed CB‐SAFF outperforms existing state‐of‐the‐art sense‐amplifier flip‐flop designs at a low supply voltage operation from 0.16 to 0.6 V in terms of power delay product and clock to output propagation delay performance metrics. In addition, the proposed CB‐SAFF can also sample low‐swing data signals down to 0.2 V even at a 0.16 V supply voltage and 1 MHz clock frequency, thus making it highly suitable for applications that demand high speed and low power consumption such as for use in ultra‐low voltage Internet of Things, wireless sensor nodes and smart motes.
Magnetic field in a young circumbinary disk
Authors: Alves F. O. , Girart J. M. , Padovani M. , Galli D. , Franco G. A. P. , Caselli P. , Vlemmings W. H. T. , Zhang Q. , Wiesemeyer H. 
Published: June 2018

Context. Polarized continuum emission at millimeter-to-submillimeter wavelengths is usually attributed to thermal emission from dust grains aligned through radiative torques with the magnetic field. However, recent theoretical work has shown that under specific conditions polarization may arise from self-scattering of thermal emission and by radiation fields from a nearby stellar object.
Aims. We use multi-frequency polarization observations of a circumbinary disk to investigate how the polarization properties change at distinct frequency bands. Our goal is to discern the main mechanism responsible for the polarization through comparison between our observations and model predictions for each of the proposed mechanisms.
Methods. We used the Atacama Large Millimeter/submillimeter Array to perform full polarization observations at 97.5 GHz (Band 3), 233 GHz (Band 6) and 343.5 GHz (Band 7). The ALMA data have a mean spatial resolution of 28 AU. The target is the Class I object BHB07-11, which is the youngest object in the Barnard 59 protocluster. Complementary Karl G. Jansky Very Large Array observations at 34.5 GHz were also performed and revealed a binary system at centimetric continuum emission within the disk.
Results. We detect an extended and structured polarization pattern that is remarkably consistent between the three bands. The distribution of polarized intensity resembles a horseshoe shape with polarization angles following this morphology. From the spectral index between Bands 3 and 7, we derived a dust opacity index β ~ 1 consistent with maximum grain sizes larger than expected to produce self-scattering polarization in each band. The polarization morphology and the polarization levels do not match predictions from self-scattering. On the other hand, marginal correspondence is seen between our maps and predictions from a radiation field model assuming the brightest binary component as main radiation source. Previous molecular line data from BHB07-11 indicates disk rotation. We used the DustPol module of the ARTIST radiative transfer tool to produce synthetic polarization maps from a rotating magnetized disk model assuming combined poloidal and toroidal magnetic field components. The magnetic field vectors (i.e., the polarization vectors rotated by 90°) are better represented by a model with poloidal magnetic field strength about three times the toroidal one.
Conclusions. The similarity of our polarization patterns among the three bands provides a strong evidence against self-scattering and radiation fields. On the other hand, our data are reasonably well reproduced by a model of disk with toroidal magnetic field components slightly smaller than poloidal ones. The residual is likely to be due to the internal twisting of the magnetic field due to the binary system dynamics, which is not considered in our model.
Vitamine und Spurenelemente in der Onkologie
Authors: Holch Julian , Michl Marlies , Heinemann Volker , Erickson Nicole 
Published: June 2018

ZusammenfassungVitamine und Spurenelemente werden häufig von Patienten eingenommen, um Tumorerkrankungen vorzubeugen oder deren Fortschreiten zu verhindern. Dies geschieht oft auch ohne Wissen des behandelnden Arztes. Der vorliegende Artikel beleuchtet die aktuelle Evidenzlage zu den meist untersuchten Mikronährstoffen und leitet hieraus konkrete Handlungsempfehlungen ab.