julilili42/papers huggingface dataset:
Biosynthesis of Zinc Substituted Magnetite Nanoparticles with Enhanced Magnetic Properties
2013-12-16

The magnetic moments of magnetite nanoparticles are dramatically enhanced through the addition of zinc in a microbiologically driven synthesis procedure. The particles are produced through the reduction of Fe(III)‐compounds containing Zn(II) by the iron reducing bacterium Geobacter sulfurreducens . Results indicate a significant increase in the saturation magnetization by over 50% compared to magnetite at both room and low temperatures for relatively minor quantities of zinc substitution. A maximum saturation magnetization of nearly 100 emu g −1 of sample is measured at room temperature. Analysis of the cation site ordering reveals a complex dependence on the Zn content, with the combined effect of Zn substitution of Fe 3+ ions on tetrahedral sites, together with Fe 2+ cation oxidation, leading to the observed magnetization enhancement for low Zn doping levels. The improved magnetic properties give superior performance in MRI applications with an MRI contrast enhancement among the largest values reported, being more than 5 times larger than a commercial contrast agent (Feridex) measured under identical conditions. The synthesis technique applied here involves an environmentally benign route and offers the potential to tune the magnetic properties of magnetic nanoparticles, with increased overall magnetization desirable for many different commercial applications.
Impact of Heterogeneity on Oxygen Transfer in a Fluctuating Capillary Fringe
2013-12-16

Abstract We performed quasi‐two‐dimensional flow through laboratory experiments to study the effect of a coarse‐material inclusion, located in the proximity of the water table, on flow and oxygen transfer in the capillary fringe. The experiments investigate different phases of mass transfer from the unsaturated zone to anoxic groundwater under both steady‐state and transient flow conditions, the latter obtained by fluctuating the water table. Monitoring of flow and transport in the different experimental phases was performed by visual inspection of the complex flow field using a dye tracer solution, measurement of oxygen profiles across the capillary fringe, and determination of oxygen fluxes in the effluent of the flow‐through chamber. Our results show significant effects of the coarse‐material inclusion on oxygen transfer during the different phases of the experiments. At steady state, the oxygen flux across the unsaturated/saturated interface was considerably enhanced due to flow focusing in the fully water‐saturated coarse‐material inclusion. During drainage, a zone of higher water saturation formed in the fine material overlying the coarse lens. The entrapped oxygen‐rich aqueous phase contributed to the total amount of oxygen supplied to the system when the water table was raised back to its initial level. In case of imbibition, pronounced air entrapment occurred in the coarse lens, causing oxygen to partition between the aqueous and gaseous phases. The oxygen mass supplied to the anoxic groundwater following the imbibition event was found to be remarkably higher (approximately seven times) in the heterogeneous system compared with a similar experiment performed in a homogeneous porous medium.
Sensitivity and Specificity of Hypnosis Effects on Gastric Myoelectrical Activity
2013-12-16

Imagination with and without hypnosis exhibits similar changes in subjective and objective measures in response to imagining an appetizing and an unappetizing food, indicating high sensitivity but low specificity.
Luther’s Roots in Monastic-Mystical Piety
2013-12-16

The literature of a deepening fifteenth-century monastic spirituality focused on humility, based on Bonaventure and Bernard of Clairvaux, expressed in works from the 'Upper-Rhenish' circle, especially JohannesTauler, provided significant impetus to Luther's theological development. He turned away from Dionysian mysticism, but Taulerian mystical theology, emphasizing the centrality of penance, remorse for sin, and the comfort given by Christ's suffering and death, played a crucial role in cultivating his sense of the unconditional nature of God's grace. These ideas led him into his critique of indulgence practice and to editing the Theologia deutsch, his first published work. He grasped many insights of 'mystical theologians' and transformed them, largely moving beyond them.
Helium Ion Microscopy (HIM) for the imaging of biological samples at sub-nanometer resolution
2013-12-17

Scanning Electron Microscopy (SEM) has long been the standard in imaging the sub-micrometer surface ultrastructure of both hard and soft materials. In the case of biological samples, it has provided great insights into their physical architecture. However, three of the fundamental challenges in the SEM imaging of soft materials are that of limited imaging resolution at high magnification, charging caused by the insulating properties of most biological samples and the loss of subtle surface features by heavy metal coating. These challenges have recently been overcome with the development of the Helium Ion Microscope (HIM), which boasts advances in charge reduction, minimized sample damage, high surface contrast without the need for metal coating, increased depth of field, and 5 angstrom imaging resolution. We demonstrate the advantages of HIM for imaging biological surfaces as well as compare and contrast the effects of sample preparation techniques and their consequences on sub-nanometer ultrastructure.
Growth problems in youth elite sports. Social conditions, athletes’ experiences and sustainability consequences1
2013-12-17

In elite sports, growth and maturation are important preconditions for advancing performance and athletic development. However, intensive training at an early age may contribute to the occurrence of growth problems in adolescent athletes. In the elite sport context, growth problems are most often considered biomedical phenomena or reduced to individual disposition. Consequently, their social origins have gone unexamined. Drawing on interviews with German youth elite athletes, we outline how social conditions (e.g. discipline-specific body ideals and early selection) contribute to the genesis of growth problems. Furthermore, we offer insight into athletes' problematic growth experiences and analyze them as a risky condition for successful socialization into elite sports. In adopting the language of sustainability, we understand growth problems as an example of 'unsustainability'. We examine how they affect athletes' individual sustained development, safety, well-being and capacity building, and also question the organizational sustainability of high performance sports. We conclude by outlining the implications for coaching practices and the adjustments needed in the organization of youth elite sports.
Quantum criticality and population trapping of fermions by non-equilibrium lattice modulations
2013-12-17

An ultracold gas of interacting fermionic atoms in a three-dimensional optical lattice is considered, where the lattice potential strength is periodically modulated. This non-equilibrium system is non-perturbatively described by means of a Keldysh–Floquet–Green's function approach for Mott–Hubbard systems employing a generalized dynamical mean field theory (DMFT). Strong repulsive interactions between different atoms lead to a Mott insulator state for the equilibrium system, but the additional external driving at zero temperature yields a non-equilibrium quantum critical behavior, where an infinite number of Floquet states arise and a transition to the liquid and conducting phase is given.
Structure–function analysis of the ATP‐driven glycolipid efflux pump DevBCA reveals complex organization with TolC/HgdD
2013-12-17

In Gram‐negative bacteria, trans‐envelope efflux pumps have periplasmic membrane fusion proteins (MFPs) as essential components. MFPs act as mediators between outer membrane factors (OMFs) and inner membrane factors (IMFs). In this study, structure–function relations of the ATP‐driven glycolipid efflux pump DevBCA‐TolC/HgdD from the cyanobacterium Anabaena sp. PCC 7120 were analyzed. The binding of the MFP DevB to the OMF TolC absolutely required the respective tip‐regions. The interaction of DevB with the IMF DevAC mainly involved the β‐barrel and the lipoyl domain. Efficient binding to DevAC and TolC, substrate recognition and export activity by DevAC were dependent on stable DevB hexamers.
Rule Activity Related to Spatial and Numerical Magnitudes: Comparison of Prefrontal, Premotor, and Cingulate Motor Cortices
2013-12-17

Abstract In everyday situations, quantitative rules, such as “greater than/less than,” need to be applied to a multitude of magnitude comparisons, be they sensory, spatial, temporal, or numerical. We have previously shown that rules applied to different magnitudes are encoded in the lateral PFC. To investigate if and how other frontal lobe areas also contribute to the encoding of quantitative rules applied to multiple magnitudes, we trained monkeys to switch between “greater than/less than” rules applied to either line lengths (spatial magnitudes) or dot numerosities (discrete numerical magnitudes). We recorded single-cell activity from the dorsal premotor cortex (dPMC) and cingulate motor cortex (CMA) and compared it with PFC activity. We found the largest proportion of quantitative rule-selective cells in PFC (24% of randomly selected cells), whereas neurons in dPMC and CMA rarely encoded the rule (6% of the cells). In addition, rule selectivity of individual cells was highest in PFC neurons compared with dPMC and CMA neurons. Rule-selective neurons that simultaneously represented the “greater than/less than” rules applied to line lengths and numerosities (“rule generalists”) were exclusively present in PFC. In dPMC and CMA, however, neurons primarily encoded rules applied to only one of the two magnitude types (“rule specialists”). Our data suggest a special involvement of PFC in representing quantitative rules at an abstract level, both in terms of the proportion of neurons engaged and the coding capacities.
Relation between isospin-symmetry-breaking correction to superallowedβdecay and the energy of the charge-exchange giant monopole resonance
2013-12-17

After application of an analytical transformation, a new exact representation\\nfor the nuclear isospin-symmetry breaking correction to superallowed\\nbeta decay is obtained. The correction is shown to be essentially the\\nreciprocal of the square of an energy parameter which characterizes\\nthe charge-exchange monopole strength distribution. The proportionality\\ncoefficient in this relation is determined by basic properties of the ground\\nstate of the even-even parent nucleus, and should be reliably calculable in any\\nrealistic nuclear model. Therefore, the single parameter contains\\nall the information about the properties of excited states needed to\\ndescribe . This parameter can possibly be determined experimentally\\nby charge-exchange reactions. Basic quantities of interest are calculated\\nwithin the isospin-consistent continuum random phase approximation, and the\\nvalues of are compared with the corresponding results from other\\napproaches.\\n
Impaired immune defense in hemodialysis patients: Role of α‐defensins?
2013-12-17

Abstract The mechanisms underlying the impaired immune response in hemodialysis ( HD ) patients are not completely understood. The α‐defensins human neutrophil peptides‐1, 2, and 3 are low molecular weight peptides with antimicrobial activity and important effector molecules of innate immune responses. We now examined the expression of these peptides in HD patients. Seventy‐six patients on chronic HD treatment (mean time on HD 5.8 years; mean age 70 years) were studied and compared with 38 healthy volunteers and 20 patients with infections and normal renal function. Expression of α‐defensins was analyzed semiquantitatively in leukocytes on the messenger RNA ( mRNA ) level by reverse transcriptase polymerase chain reaction; the α‐defensin protein levels in serum were detected by enzyme‐linked immunosorbent assay. α‐Defensin concentrations (140 ± 10.5 ng/mL; mean ± standard error of the mean) as well as mRNA levels in leukocytes (82.9 ± 7.9 arbitrary units [a.u.]) in HD patients were not significantly different from those in healthy volunteers (156 ± 15.2 ng/mL; 81.4 ± 11.3 a.u.). Defensin levels were independent of the time of the patient on HD and their age. During infection periods (mean increase of the C ‐reactive protein to 161 ± 17.3 mg/L), defensin serum levels increased to 321 ± 65 ng/mL (P &lt; 0.005) and mRNA expression in leukocytes to 159 ± 19.2 a.u. (P &lt; 0.05). These increases were not significantly different from those in patients with normal renal function (298 ± 46.8 ng/mL and 128 ± 9.1 a.u., respectively) suffering from infections ( C ‐reactive protein 222 ± 26.6 mg/L). Our results suggest that the impaired immune defense in dialysis patients is not due to a deficiency in α‐defensins in these patients as neither basal levels nor expression during infections were reduced compared with subjects with normal renal function.
PNPLA6 mutations cause Boucher-Neuhäuser and Gordon Holmes syndromes as part of a broad neurodegenerative spectrum
2013-12-18

Boucher-Neuhäuser and Gordon Holmes syndromes are clinical syndromes defined by early-onset ataxia and hypogonadism plus chorioretinal dystrophy (Boucher-Neuhäuser syndrome) or brisk reflexes (Gordon Holmes syndrome). Here we uncover the genetic basis of these two syndromes, demonstrating that both clinically distinct entities are allelic for recessive mutations in the gene PNPLA6. In five of seven Boucher-Neuhäuser syndrome/Gordon Holmes syndrome families, we identified nine rare conserved and damaging mutations by applying whole exome sequencing. Further, by dissecting the complex clinical presentation of Boucher-Neuhäuser syndrome and Gordon Holmes syndrome into its neurological system components, we set out to analyse an additional 538 exomes from families with ataxia (with and without hypogonadism), pure and complex hereditary spastic paraplegia, and Charcot-Marie-Tooth disease type 2. We identified four additional PNPLA6 mutations in spastic ataxia and hereditary spastic paraplegia families, revealing that Boucher-Neuhäuser and Gordon Holmes syndromes in fact represent phenotypic clusters on a spectrum of neurodegenerative diseases caused by mutations in PNPLA6. Structural analysis indicates that the majority of mutations falls in the C-terminal phospholipid esterase domain and likely inhibits the catalytic activity of PNPLA6, which provides the precursor for biosynthesis of the neurotransmitter acetylcholine. Our findings show that PNPLA6 influences a manifold of neuronal systems, from the retina to the cerebellum, upper and lower motor neurons and the neuroendocrine system, with damage of this protein causing an extraordinarily broad continuous spectrum of associated neurodegenerative disease.
Parkinson-related LRRK2 mutation R1441C/G/H impairs PKA phosphorylation of LRRK2 and disrupts its interaction with 14-3-3
2013-12-18

Significance Leucine-rich repeat kinase 2 (LRRK2) is a multidomain protein implicated in Parkinson disease, and cAMP-dependent protein kinase (PKA) has been suggested to act as an upstream kinase phosphorylating LRRK2. Using a phosphoproteomics approach, we identified several novel PKA phosphorylation sites on LRRK2. We could demonstrate that one PKA phosphosite comprises the second most common mutation in LRRK2 (R1441C/G/H) attributed to Parkinson disease. Our findings reveal that this site is mandatory for subsequent 14-3-3 binding and affects LRRK2 kinase activity. These data provide a mechanistic insight into the regulation of LRRK2 kinase activity and its perturbation by disease-associated mutations.
BRAF‐Mutated Pleomorphic Xanthoastrocytoma is Associated with Temporal Location, Reticulin Fiber Deposition and CD34 Expression
2013-12-18

Abstract BRAF V600E mutation and homozygous deletion of CDKN2A ( p 16) are frequent molecular alterations in pleomorphic xanthoastrocytomas ( PXA s). We investigated 49 PXAs for clinical, histological and immunohistochemical characteristics related to BRAF mutation status. BRAF mutation was detected by immunohistochemical assay and DNA sequencing in 38/49 (78%) tumors. All but one PXA located in the temporal lobe harbored a BRAF V600E mutation (23/24; 96%) compared with 10/19 nontemporal PXAs (53%; P = 0.0009). Histological and immunohistochemical analysis demonstrated increased reticulin deposition (76% vs. 27%; P = 0.003) and a more frequent expression of CD 34 in BRAF ‐mutant PXAs (76% vs. 27%; P = 0.003). We further investigated the utility of combined BRAF V600E ( VE 1) and p 16 analysis by immunohistochemistry to distinguish PXAs from relevant histological mimics like giant‐cell glioblastoma. Among PXAs , 38/49 (78%) were VE 1‐positive, and 30/49 (61%) had a loss of p16 expression. The combined features ( VE 1 positivity/ p 16 loss) were observed in 25/49 PXAs (51%) but were not observed in giant‐cell glioblastoma ( VE 1 0/28, p 16 loss 14/28). We demonstrate that temporal location, reticulin deposition and CD 34 expression are associated with BRAF mutation in PXA . Combined VE 1 positivity and p 16 loss represents a frequent immunoprofile of PXA and may therefore constitute an additional diagnostic tool for its differential diagnosis.
Influence of physical activity on T1 and T2* relaxation times of healthy achilles tendons at 3T
2013-12-18

Purpose To evaluate longitudinal (T1) and transverse (T2*) relaxation times at different Achilles tendon locations (insertion, mid‐portion, and musculotendinous area) in a cohort of subjects with variable tendon straining activity, but without any signs of tendinopathy. Materials and Methods T1 and T2* relaxation times of the Achilles tendon were measured using an ultrashort echo time (UTE) imaging sequence with flip angle and echo time variation on a 3T whole‐body clinical magnetic resonance (MR) scanner. Twenty‐four tendons of 12 healthy volunteers and 18 tendons of nine healthy recreational long‐distance runners (average weekly running distance of 47.4 ± 5.3 km) were enrolled. Results Mean T1 values of the whole tendon showed no marked group differences, whereas T2* relaxation times of runners were significantly longer (mean percentage increase 15.7 ± 4.9%; P = 0.0181) compared to controls. Regarding group differences for the investigated insertional, mid‐portion, and musculotendinous area of the Achilles tendon, only the mid‐portion of the Achilles tendon in the running group presented significantly longer T2* values (mean percentage increase 29.1 ± 23.0%; P = 0.0420) in comparison to the control group. Conclusion Prolonged T2* values especially in the mid‐portion of the Achilles tendon of runners are likely to reflect an adaptation of the tendon microstructure to repetitive tendon straining activity. J. Magn. Reson. Imaging 2015;41:193–201. © 2013 Wiley Periodicals, Inc .
Metallic oxide nanoparticles stimulate blood coagulation independent of their surface charge
2013-12-18

Abstract Positively charged metallic oxides prevent blood coagulation whereas negatively charged metallic oxides are thrombogenic. This study was performed to examine whether this effect extends to metallic oxide nanoparticles. Oscillation shear rheometry was used to study the effect of zinc oxide and silicon dioxide nanoparticles on thrombus formation in human whole blood. Our data show that oscillation shear rheometry is a sensitive and robust technique to analyze thrombogenicity induced by nanoparticles. Blood without previous contact with nanoparticles had a clotting time (CT) of 16.7 ± 1.0 min reaching a maximal clot strength (CS) of 16 ± 14 Pa (G') after 30 min. ZnO nanoparticles (diameter 70 nm, +37 mV zeta‐potential) at a concentration of 1 mg/mL prolonged CT to 20.8 ± 3.6 min and provoked a weak clot (CS 1.5 ± 1.0 Pa). However, at a lower concentration of 100 μg/mL the ZnO particles dramatically reduced CT to 6.0 ± 0.5 min and increased CS to 171 ± 63 Pa. This procoagulant effect decreased at lower concentrations reaching the detection limit at 10 ng/mL. SiO 2 nanoparticles (diameter 232 nm, −28 mV zeta‐potential) at high concentrations (1 mg/mL) reduced CT (2.1 ± 0.2 min) and stimulated CS (249 ± 59 Pa). Similar to ZnO particles, this procoagulant effect reached a detection limit at 10 ng/mL. Nanoparticles in high concentrations reproduce the surface charge effects on blood coagulation previously observed with large particles or solid metal oxides. However, nanoparticles with different surface charges equally well stimulate coagulation at lower concentrations. This stimulation may be an effect which is not directly related to the surface charge. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 102B: 897–902, 2014.
Coupling of optical far fields into apertureless plasmonic nanofiber tips
2013-12-18

This paper reports on the excitation of surface plasmons on gold-coated\\nnanofibre tips by side-illumination with a laser beam and the coupling of the\\nsurface plasmons to the optical fiber. The measurements show a strong\\ndependence of the coupling efficiency on the incidence angle with a maximum\\ncoupling efficiency on the order of few percent. Moreover, the fibre tip was\\nused as scanning probe device for measuring the beam waist of a focussed laser\\nbeam. This work is motivated by the goal to use such plasmonic nanofibre tips\\nin quantum optics experiments with cold atoms.\\n
Ontogenetic Study of Allometric Variation in Homo and Pan Mandibles
2013-12-18

ABSTRACT Investigating ontogenetic variation and allometry in the mandible can provide valuable insight and aid in addressing questions related to the ontogeny of the skull. Here, patterns of ontogenetic shape change and allometric trajectories were examined in the mandible of 187 sub‐adult and adult humans, bonobos, and chimpanzees. Procrustes‐based geometric morphometrics was employed to quantify and analyze mandibular form. Thirty three‐dimensional landmarks were used to capture the overall morphology of the mandible, and the landmarks were analyzed as a whole and subdivided into separate anterior and posterior units. Principal component analyses in Procrustes shape–space and form–space, and multivariate regressions were used to examine patterns of ontogenetic and allometric shape change. Results suggest that humans are distinct from Pan both in their mandibular morphology, particularly in the anterior‐alveolar region, and direction of allometric trajectory. Chimpanzees and bonobos have parallel ontogenetic trajectories, but also show differences in mandibular shape. Species‐specific features and adult mandibular shape are established before or by the eruption of the deciduous dentition. This suggests that developmental processes prior to deciduous teeth eruption have a stronger effect establishing taxa‐specific phenotypes than later postnatal effects. This additionally implies that divergent trajectories between Pan and Homo do not contribute much to the adult mandibular shape after deciduous teeth eruption. Separate analyses of the anterior‐alveolar region and ascending ramus show that these regions are semi‐independent in their developmental pattern of shape change and allometry. This implies that allometric variation and ontogenetic shape change in the hominoid mandible is decoupled. Anat Rec, 297:261–272, 2014. © 2013 Wiley Periodicals, Inc.