julilili42/papers huggingface dataset:
Corticofugal projection patterns of whisker sensorimotor cortex to the sensory trigeminal nuclei
2015-09-30

The primary (S1) and secondary (S2) somatosensory cortices project to several trigeminal sensory nuclei. One putative function of these corticofugal projections is the gating of sensory transmission through the trigeminal principal nucleus (Pr5), and some have proposed that S1 and S2 project differentially to the spinal trigeminal subnuclei, which have inhibitory circuits that could inhibit or disinhibit the output projections of Pr5. Very little, however, is known about the origin of sensorimotor corticofugal projections and their patterns of termination in the various trigeminal nuclei. We addressed this issue by injecting anterograde tracers in S1, S2 and primary motor (M1) cortices, and quantitatively characterizing the distribution of labeled terminals within the entire rostro-caudal chain of trigeminal sub-nuclei. We confirmed our anterograde tracing results by injecting retrograde tracers at various rostro-caudal levels within the trigeminal sensory nuclei to determine the position of retrogradely labeled cortical cells with respect to S1 barrel cortex. Our results demonstrate that S1 and S2 projections terminate in largely overlapping regions but show some significant differences. Whereas S1 projection terminals tend to cluster within the principal trigeminal (Pr5), caudal spinal trigeminal interpolaris (Sp5ic), and the dorsal spinal trigeminal caudalis (Sp5c), S2 projection terminals are distributed in a continuum across all trigeminal nuclei. Contrary to the view that sensory gating could be mediated by differential activation of inhibitory interconnections between the spinal trigeminal subnuclei, we observed that projections from S1 and S2 are largely overlapping in these subnuclei despite the differences noted earlier.
Cognitive foundations of organizational learning: re-introducing the distinction between declarative and non-declarative knowledge
2015-09-30

Contemporary research into socio-cognitive foundations of organizational learning tends to disregard the distinction between declarative and non-declarative knowledge. By reviewing the literature from organizational learning research and cognitive psychology we explain that this distinction is crucial. We describe the foundations of organizational learning by referring to models that consider the interplay between individual and collective knowledge-related processes in organizations. We highlight the existence of a research gap resulting from the finding that these approaches have widely neglected the existence of different types of knowledge. We then elaborate on characteristics of declarative and non-declarative knowledge in general, consider organizations as structures of distributed cognition, and discuss the relationship between organizational knowledge and practice. Subsequently, we examine the role of declarative and non-declarative knowledge in the context of organizational learning. Here, we analyze (1) the cognitive and social mechanisms underlying the development of declarative and non-declarative knowledge within structures of distributed cognition; and (2) the relationship between alterations in declarative and non-declarative types of knowledge on the one hand and changes in organizational practice on the other. Concluding, we discuss implications of our analysis for organizational learning research. We explain how our integrative perspective may offer starting points for a refined understanding of the sub-processes involved in organizational learning and unlearning and may support a better understanding of practical problems related to organizational learning and change.
Efficiency of advanced wastewater treatment technologies for the reduction of hormonal activity in effluents and connected surface water bodies by means of vitellogenin analyses in rainbow trout (Oncorhynchus mykiss) and brown trout (Salmo trutta f. fario)
2015-09-30

Endocrine effects in the aquatic environment are in the focus of scientists and media along with debates on the necessity of further steps in wastewater treatment. In the present study VTG responses were compared to evaluate upgrades at wastewater treatment plants (WWTPs). We investigated several advanced sewage treatment technologies at two WWTPs connected to the Schussen, a tributary of Lake Constance, for the reduction of hormonal activity: (1) a powdered activated charcoal filter at the WWTP Langwiese; and (2) a combination of ozonation, sand filter, and granulated activated carbon filter at the WWTP Eriskirch. Rainbow trout and brown trout were either directly exposed to the effluents in aquaria or cages, or in a bypass system flown through by surface water of the Schussen. As a reference, trout were kept in bypass aquaria at the Argen River, which is less influenced by micropollutants. As a biomarker for estrogenicity, we analyzed the yolk precursor protein vitellogenin in immature rainbow trout and brown trout and in trout larvae (100 days post-fertilization) prior to and after the upgrade with the new technologies. Trout of different ages and species were used to detect differences in their sensitivity. At both bypass stations, larvae of brown trout showed significantly higher vitellogenin levels prior to the upgrade compared to negative control levels. Female brown trout exposed at the bypass station downstream of the WWTP showed decreased vitellogenin levels after the upgrade. In 1-year-old immature trout directly exposed to the respective effluents, no significant effects of the upgrades on vitellogenin levels were found. In general, larger effects were observed in brown trout than in rainbow trout, indicating that they are more sensitive test organisms.
Higher Lipoprotein (a) Levels Are Associated with Better Pulmonary Function in Community-Dwelling Older People – Data from the Berlin Aging Study II
2015-09-30

Reduced pulmonary function and elevated serum cholesterol levels are recognized risk factors for cardiovascular disease. Currently, there is some controversy concerning relationships between cholesterol, LDL-cholesterol, HDL-cholesterol, serum triglycerides and lung function. However, most previous studies compared patients suffering from chronic obstructive pulmonary disease (COPD) with healthy controls, and only a small number examined this relationship in population-based cohorts. Moreover, lipoprotein a [Lp(a)], another lipid parameter independently associated with cardiovascular diseases, appears not to have been addressed at all in studies of lung function at the population level. Here, we determined relationships between lung function and several lipid parameters including Lp(a) in 606 older community-dwelling participants (55.1% women, 68Â±4 years old) from the Berlin Aging Study II (BASE-II). We found a significantly lower forced expiration volume in 1 second (FEV1) in men with low Lp(a) concentrations (t-test). This finding was further substantiated by linear regression models adjusting for known covariates, showing that these associations are statistically significant in both men and women. According to the highest adjusted model, men and women with Lp(a) levels below the 20th percentile had 217.3ml and 124.2ml less FEV1 and 239.0ml and 135.2ml less FVC, respectively, compared to participants with higher Lp(a) levels. The adjusted models also suggest that the known strong correlation between pro-inflammatory parameters and lung function has only a marginal impact on the Lp(a)-pulmonary function association. Our results do not support the hypothesis that higher Lp(a) levels are responsible for the increased CVD risk in people with reduced lung function, at least not in the group of community-dwelling older people studied here.
Noise masking of White's illusion exposes the weakness of current spatial filtering models of lightness perception
2015-10-01

Spatial filtering models are currently a widely accepted mechanistic account of human lightness perception. Their popularity can be ascribed to two reasons: They correctly predict how human observers perceive a variety of lightness illusions, and the processing steps involved in the models bear an apparent resemblance with known physiological mechanisms at early stages of visual processing. Here, we tested the adequacy of these models by probing their response to stimuli that have been modified by adding narrowband noise. Psychophysically, it has been shown that noise in the range of one to five cycles per degree (cpd) can drastically reduce the strength of some lightness phenomena, while noise outside this range has little or no effect on perceived lightness. Choosing White's illusion (White, 1979) as a test case, we replicated and extended the psychophysical results, and found that none of the spatial filtering models tested was able to reproduce the spatial frequency specific effect of narrowband noise. We discuss the reasons for failure for each model individually, but we argue that the failure is indicative of the general inadequacy of this class of spatial filtering models. Given the present evidence we do not believe that spatial filtering models capture the mechanisms that are responsible for producing many of the lightness phenomena observed in human perception. Instead we think that our findings support the idea that low-level contributions to perceived lightness are primarily determined by the luminance contrast at surface boundaries.
The Archean Nickel Famine Revisited
2015-10-01

Iron formations (IF) preserve a history of Precambrian oceanic elemental abundance that can be exploited to examine nutrient limitations on early biological productivity. However, in order for IF to be employed as paleomarine proxies, lumped-process distribution coefficients for the element of interest must be experimentally determined or assumed. This necessitates consideration of bulk ocean chemistry and which authigenic ferric iron minerals controlled the sorption reactions. It also requires an assessment of metal mobilization reactions that might have occurred in the water column during particle descent and during post-depositional burial. Here, we summarize recent developments pertaining to the interpretation and fidelity of the IF record in reconstructions of oceanic trace element evolution. Using an updated compilation, we reexamine and validate temporal trends previously reported for the nickel content in IF (see Konhauser et al., 2009 ). Finally, we reevaluate the consequences of methanogen Ni starvation in the context of evolving views of the Archean ocean-climate system and how the Ni famine may have ultimately facilitated the rise in atmospheric oxygen.
Predictors of the antibody response to influenza vaccination in older adults with type 2 diabetes
2015-10-01

Objective Type 2 diabetes mellitus (T2DM) is one of the most prevalent chronic inflammatory diseases of the elderly. Its development is related to the alteration of the immune system with aging characterized by immunosenescence and inflamm-aging. In turn, T2DM also alters the immune response. As a consequence, older people with T2DM are more susceptible to influenza and to its complications as compared with healthy controls. Vaccination against influenza has shown poor efficacy in the older population and even less efficacy in patients with diabetes. We studied here the antibody response to vaccination in healthy and diabetic elderly participants. Research design and methods In 2 groups of elderly participants (healthy N=119 and T2DM N=102), we measured the immunogenicity of influenza vaccine by hemagglutination inhibition assays. We assessed several blood and functional parameters as potential predictors of the vaccine efficacy. Results We found no difference between antibody responses in diabetic elderly compared with healthy elderly. Among the biological and functional determinants, the cytomegalovirus (CMV) serostatus played a more prominent role in determining the magnitude of response. We concluded that in addition to age and diabetic status, immunological history such as CMV status should be taken into account. None of the other biological or functional parameters studied could be reliably linked to the vaccine antibody response in older adults who are not frail including those with well-controlled diabetes. Conclusions Our data strongly suggest that influenza vaccine should be administered to elderly patients with T2DM; however, the immune determinants of the antibody response to influenza vaccination should be further investigated.
Convex ancient solutions of the mean curvature flow
2015-10-01

We study solutions of the mean curvature flow which are defined for all negative times, usually called ancient solutions. We give various conditions ensuring that a closed convex ancient solution is a shrinking sphere. Examples of such conditions are: a uniform pinching condition on the curvatures, a suitable growth bound on the diameter, or a reverse isoperimetric inequality. We also study the behaviour of uniformly k-convex solutions, and consider generalizations to ancient solutions immersed in a sphere.
Facies analysis and sequence stratigraphy of the uppermost Jurassic– Lower Cretaceous Sulaiy Formation in outcrops of central Saudi Arabia
2015-10-01

ABSTRACT Uppermost Jurassic–Lower Cretaceous carbonates of the Sulaiy Formation are well exposed at the type locality Dahal Hit, and along the entire natural escarpment near Ar Riyad, the capital of the Kingdom of Saudi Arabia. This study provides a facies and sequence-stratigraphic analysis based on detailed sedimentological and gamma-ray logging of 12 outcrop sections. The sections represent the Sulaiy Formation along a 60 km-long outcrop belt, including the Hith-Sulaiy transition in a large solution cavity named Dahal Hit, situated south of Ar Riyad. The latter section is studied in detail because it is the only locality in Saudi Arabia where the Hith Anhyrite (Hith Formation in this study) to the Sulaiy Formation transition crops out. Ten lithofacies types were identified for the Sulaiy Formation including potential reservoirs such as oolitic cross-bedded grainstones, biostromal boundstones, and bioclast-rich, graded pack-to-grainstones. Lithofacies types are grouped into five facies associations: (1) offshoal, (2) transition zone, foreshoal, (4) shoal margin, and (5) shoal, distributed along a carbonate ramp. Their vertical stacking pattern revealed a systematic hierarchy of cyclicity consisting of small-scale cycles, medium-scale cycle sets and two large-scale sequences for the Sulaiy Formation. Four cycle motifs, with an average thickness of 2–4 m, are present: (1) offshoal to transition zone cycle motif, (2) offshoal to foreshoal cycle motif, (3) transition zone to shoal margin cycle motif, and foreshoal to shoal margin cycle motif. A total of 15 cycle sets, ranging between 8 and 12 m in thickness each, were interpreted. They were correlated, where possible, across the study area. Three types of medium-scale cycle sets are observed: (1) offshoal to shoal cycle set motif, (2) offshoal to foreshoal cycle set motif, and (3) shoal margin to offshoal cycle set motif. The Lower Sulaiy Sequence consists of twelve cycle sets and is interpreted to contain two Arabian Plate maximum flooding surfaces (MFS): (1) Upper Tithonian MFS J110 (147 Ma) in its lowermost part, which is interpreted to be the time-equivalent of the Manifa reservoir in subsurface Arabia. (2) Lower Berriasian MFS K10 (144 Ma) in the seventh-up cycle set. The Upper Sulaiy Sequence is only represented in the Wadi Nisah Section and is believed to be incomplete because the Sulaiy/Yamama Formation boundary was not included in our study. It is presumed to contain Upper Berriasian MFS K20 (141 Ma).
Imaging-Based Treatment Adaptation in Radiation Oncology
2015-10-01

In many tumor types, significant effort is being put into patient-tailored adaptation of treatment to improve outcome and preferably reduce toxicity. These opportunities first arose with the introduction of modern irradiation techniques (e.g., intensity-modulated radiotherapy) combined with functional imaging for more precise delineation of target volume. On the basis of functional CT, MRI, and PET results, radiation target volumes are altered during the course of treatment, or subvolumes inside the primary tumor are defined to enhance the dosing strategy. Moreover, the probability of complications to normal tissues is predicted using anatomic or functional imaging, such as in the use of CT or PET to predict radiation pneumonitis. Besides focusing, monitoring, and adapting photon therapy for solid tumors, PET also has a role in verifying proton-beam therapy. This article discusses the current state and remaining challenges of imaging-based treatment adaptation in radiation oncology.
Classification of Rhinoentomophthoromycosis into Atypical, Early, Intermediate, and Late Disease: A Proposal
2015-10-01

We suggest a clinical staging system that underlines the benefit of early case detection and may guide the duration of antifungal treatment. The scientific value of this classification is its capacity to structure and harmonize the clinical and research approach towards rhinoentomophthoromycosis.
AP-2 Is the Crucial Clathrin Adaptor Protein for CD4 Downmodulation by HIV-1 Nef in Infected Primary CD4 + T Cells
2015-10-01

ABSTRACT HIV-1 Nef-mediated CD4 downmodulation involves various host factors. We investigated the importance of AP-1, AP-2, AP-3, V1H-ATPase, β-COP, and ACOT8 for CD4 downmodulation in HIV-1-infected short hairpin RNA (shRNA)-expressing CD4 + T cells and characterized direct interaction with Nef by Förster resonance energy transfer (FRET). Binding of lentiviral Nefs to CD4 and AP-2 was conserved, and only AP-2 knockdown impaired Nef-mediated CD4 downmodulation from primary T cells. Altogether, among the factors tested, AP-2 is the most important player for Nef-mediated CD4 downmodulation.
PALEOECOLOGICAL DYNAMICS OF SHALLOW-WATER BIVALVE CARPETS FROM A LOWER JURASSIC LAGOONAL SETTING, NORTHEAST ITALY
2015-10-01

Shell beds are products of complex biological, taphonomic, and sedimentological factors. Paleoecological analysis of Pliensbachian shell accumulations from northeast Italy, Southern Alps, records successive phases of colonization and demise, each of which are characterized by specific taphonomic features and sedimentary fabrics. Field studies were augmented by serial sectioning and thin sections revealing microfacies and microtaphofacies, as well as scanning electro-microscopy (SEM) and electron backscatter diffraction (EBSD). The term bivalve carpet is introduced to describe the original geometry of the bivalve accumulation colonizing the substrate. Within a lagoonal depositional setting, small, thin-shelled Isognomonidae-like bivalves lived as endo-byssate, non-siphonate suspension feeders. These bivalves, interpreted as juveniles, constructed bivalve carpets with a primary lateral extension while lacking a distinct vertical growth. Bivalves colonized firm, dysoxic carbonate substrates consisting of a mixture of peloids, bioclasts, and chemolithotrophic iron-oxidizing bacteria. Oxygen-rich bottom currents and microbial activity stabilized the lagoon floor thus allowing for the episodic settlement of fixosessile bivalves and their autochthonous preservation. Short-term anoxic phases interpreted to reflect seasonal decreases in water energy resulted in the mass mortalities of the juvenile bivalves. The abundance of articulated, vertical orientated valve pairs in the shell accumulations indicate that the bivalve carpets were embedded soon after the death of the organisms without prior physical disturbance.
Does a Heavy Fe-Isotope Composition of Akilia Quartz-Amphibole-Pyroxene Rocks Necessitate a BIF Origin?
2015-10-01

The age and origin of the quartz-amphibole-pyroxene (qap) gneiss from the island of Akilia, southern West Greenland, have been the subject of intense debate since the light C-isotope composition of graphite inclusions in apatite was interpreted to indicate the presence of Earth's earliest biological activity. Although this claim for biogenic relicts has been vigorously challenged, the possibility that the rocks might represent some of Earth's earliest water-lain sediments and, hence, a suitable repository for life remains an open question. While some workers have suggested that the entire sequence represents an originally mafic-ultramafic igneous precursor subsequently modified by metasomatism, quartz injection, high-grade metamorphism, and extreme ductile deformation, others maintain that at least a small part of the sequence retains geochemical characteristics indicative of a chemical sedimentary origin. Fractionated Fe isotopes with δ(56)Fe values similar to those observed in Isua BIF have been reported from high-SiO2 units of qap and used to support a chemical sedimentary protolith for the qap unit. Here, we present new Fe isotope data from all lithologic variants in the qap gneiss on Akilia, including layers of undisputed ultramafic igneous origin. Since the latter require introduction of fractionated Fe into at least part of the qap unit, we argue that Fe isotopes must therefore be treated with considerable caution when used to infer BIF for part or all of the qap protolith.
On the stability domain of a DC-DC buck converter with software control loop
2015-10-01

In recent years, there has been an increasing interest in developing software controlled DC-DC converters because of their fast configurability, e.g. for several supply and load values. This paper aims at exploring the stability of a DC-DC buck converter with a software control loop in the multidimensional space of control parameters. Once the stability domain is determined, it can be further used to search for the optimal parameter values for which the output voltage of the converter satisfies specific performance requirements. In this paper, we determine the stability domain by two approaches. First, we apply an analytical method that uses an analog-to-digital transform followed by the D-decomposition technique. Second, we apply a searching algorithm developed to efficiently characterize pass/fail behavior of electronic devices. The results obtained by the two methods are directly compared and discussed. The analytical approach is more conservative in determining the stability border, identifying a sub-domain of the real one. The search-based method proved to be more accurate in determining the stability border, at the cost of additional simulation runs.
Nucleon Properties in AdS/QCD models with several Fock States
2015-10-01

We discuss a holographic soft-wall model that consider several Fock states in nucleon description. In our approach nucleon structure is a superposition of a three-valence quark state with high Fock states including an adjustable number of partons (quarks, antiquarks and gluons). With a minimal number of free parameters (dilaton scale parameter, mixing parameters of partial contributions of Fock states, coupling constants in the effective Lagrangian) we achieve a reasonable agreement with data.
ChemInform Abstract: Detection and Characterization of Compounds in the Mn‐W‐Cl System Through a Combined Thermal Scanning ‐ XRD Approach.
2015-10-01

Abstract Thermal scanning of the Mn—W—Cl system reveals the formation of four new compounds, Mn x WCl 6 (I), MnW 2 Cl 10 (II), (Mn,W) 1‐x Cl 2 (III), and MnW 6 Cl 14 (IV) upon progressive reactions of WCl 6 and Mn powder (sealed quartz tube, 125—500 °C, 2—21 d).
Insights into Structure–Activity Relationships of Bacterial RNA Polymerase Inhibiting Corallopyronin Derivatives
2015-10-02

The new compound precorallopyronin A is a stable precursor in the biosynthesis of the antibiotic corallopyronin A. This natural product was isolated from the producer strain Corallococcus coralloides B035. Together with various semisynthetically obtained corallopyronin A derivatives its antibacterial effects were evaluated. In combination with an X-ray crystallization model limitations of derivatization possibilities were revealed. The antibiotic potential of the novel precorallopyronin A is comparable to that of the structurally more complex corallopyronin A, which highlights that the additional chiral center is not essential for activity.