The Geography of Non-formal Manifolds

We show that there exist non-formal compact oriented manifolds of dimension $n$ and with first Betti number $b_1=b\geq 0$ if and only if $n\geq 3$ and $b\geq 2$, or $n\geq (7-2b)$ and $0\leq b\leq 2$. Moreover, we present explicit examples for each one of these cases.Comment: 8 pages, one reference update

Earth's first snowball event: Evidence from the early Paleoproterozoic Huronian Supergroup

Ever since it was first proposed that the Earth completely froze during glaciations ∼ 640 million years ago evidence supporting this hypothesis has been increasing, primarily from samples of carbonates directly overlying glacial diamictites, termed cap carbonates. However, this was not the first extensive glacial period that affected planet Earth: ∼1750 million years prior to Neoproterozoic glaciations the Earth went through its first major glacial episode, the early Paleoproterozoic Huronian glaciations. The second Huronian ice advance deposited the Bruce Formation, with its overlying cap carbonate, the Espanola Formation. This up to ∼ 300 m thick succession of limestone, siltstone, dolostone and sandstone overlies diamictite containing a dropstone-bearing layer with δ13Ccarb of −10‰. The 12C-enriched interval also has rare earth element (REE) patterns with negative Eu anomalies, radiogenic Sr isotopes, and negative εNd(0) in the carbonate. The first of these observations is probably due to highly reducing conditions in the sediment, and the possible thawing of methane-rich areas, releasing fluids that mixed with the overlying bottom waters; the last two reflect the diagenetic incorporation into the carbonate of radiogenic Sr, and derivation of REEs, including Nd, from abundant silty loess. This infers a stratified water mass with a relatively stagnant bottom layer during disintegration of an ice shelf. Above this REE patterns through the basal Espanola become increasingly more light depleted upwards, C becomes heavier, Sr is less radiogenic, εNd(0) is near 0 and one area has up to ∼ 1300 ppm Ba incorporated into the carbonate, indicating breakdown of water-mass stratification. Vertically over ∼ 200 m δ13Ccarb increases from −4.5 to −2.5‰ as the environment shallowed incorporating gradually increasing amounts of seawater into the freshwater plume, which initially extended to depths below wave base. Strata deposited in the upper Espanola near the strandline contain layers of Fe-Mn-rich dolomite with positive Eu anomalies reflecting Paleoproterozioc seawater composition dominating even the nearshore by this time. These observations are similar to those from Neoproterozoic cap carbonates, and provide new evidence for the possibly snowball Earth-like nature of the ∼ 2.4 Ga Bruce glaciation

An X-Ray Spectral Classification Algorithm with Application to Young Stellar Clusters

A large volume of low signal-to-noise, multidimensional data is available from the CCD imaging spectrometers aboard the Chandra X-Ray Observatory and the X-Ray Multimirror Mission (XMM-Newton). To make progress analyzing this data,itisessentialtodevelopmethods tosort,classify,and characterize thevastlibrary of X-rayspectrain a nonparametric fashion (complementary to current parametric model fits). We have developed a spectral classification algorithm that handles large volumes of data and operates independently of the requirement of spectral model fits.Weuseprovenmultivariatestatisticaltechniquesincludingprincipalcomponentanalysisandanensembleclassifier consistingofagglomerativehierarchicalclusteringandK-meansclusteringappliedforthefirsttimeforspectralclassification.Thealgorithmpositionsthesourcesinamultidimensionalspectralsequenceandthengroupstheorderedsources into clusters based on their spectra. These clusters appear more distinct for sources with harder observed spectra. The apparent diversity ofsource spectra isreduced toa three-dimensional locus inprincipal component space,withspectral outliers falling outside this locus. The algorithm was applied to a sample of 444 strong sources selected from the 1616 X-ray emitting sources detected in deep Chandra imaging spectroscopy of the Orion Nebula Cluster. Classes form sequencesinNH,AV,andaccretionactivityindicators,demonstratingthatthealgorithmefficientlysortstheX-raysources into a physically meaningful sequence. The algorithm also isolates important classes of very deeply embedded, active young stellar objects, and yields trends between X-ray spectral parameters and stellar parameters for the lowest mass, pre‐main-sequence stars

Increased ¹⁸F-FDG signal recovery from small physiological structures in digital PET/CT and application to the pituitary gland.

On conventional PET/CT, and under physiological conditions, the volume of the pituitary gland (PG) is small, and its metabolic activity is commonly comparable to the surrounding background level in <sup>18</sup> F-FDG imaging. We compared the physiological <sup>18</sup> F-FDG uptake of the PG in patients imaged with digital PET (dPET) and with conventional PET (cPET). Additionally, we performed phantom experiments to characterize signal recovery and detectability of small structures. We retrospectively included 10 dPET and 10 cPET patients and measured PG SUVmax, SUVmean and SUVratio (using cerebellum as reference). We imaged a modified NEMA/IEC phantom with both dPET and cPET (background activity 5 kBq/mL, and 3× and 5× higher concentrations in ∅2-20-mm spherical inserts). Mean recovery coefficients (RCmean) and signal-difference-to-noise-ratio (SDNR) were computed to assess lesion detectability. Patients imaged with dPET presented higher PG SUVmax and SUVratio (SUVR) compared to patients imaged with cPET (4.7 ± 2.05 vs. 2.9 ± 0.64, p = 0.004; and 0.62 ± 0.25 vs 0.39 ± 0.09, p = 0.029, respectively), while there was no difference for SUVmean (2.7 ± 1.32 vs 2.1 ± 0.44, p = 0.39). Thus, with a SUV readout scale of 0-5 g/mL, normal PG appeared abnormally hot with dPET, but not with cPET. Phantom evidenced higher RCmean in dPET compared to cPET. For both 3x and 5x measurements, lesion detectability according to size was systematically superior with dPET. In conclusion, patients imaged with dPET presented higher <sup>18</sup> F-FDG physiological uptake of the PG as compared to patients imaged with cPET. These findings were supported by phantom experiments demonstrating superior signal recovery and small region detectability with dPET. Awareness of this new "higher" SUV of the normal <sup>18</sup> F-FDG uptake of the PG is important to avoid potential pitfalls in image interpretation, notably in oncologic patients treated with immunotherapy, who are at increased risk to develop hypophysitis

Papillary Thyroid Carcinoma with Desmoid-Type Fibromatosis: Review of Published Cases.

Desmoid-type fibromatosis (DTF) is a very rare variant of papillary thyroid carcinoma (PTC). It is essentially a dual tumor with a component of classical PTC with malignant epithelial proliferation (BRAF-mutated) and another component of mesenchymal proliferation (CTNNB1-mutated). We conducted a literature review on PTC-DTF. In total, 31 articles were identified, that together reported on 54 patients. The mean age was 47 years, with a 2.2:1 female predominance. No ultrasound features were found to be helpful in differentiating PTC-DTF from other PTC variants. Of the 43 cases that reported histological details, 60% had locally infiltrative disease (T3b or T4). Around 48% had cervical lymph node metastases, but none had distant metastases. While PTC-DTF may be locally more aggressive than classic PTC, its overall behavior is similar and can include extrathyroidal extension and lymph node metastases, which may contain a stromal component and show extranodal invasion. The mainstay of treatment for PTC-DTF is surgery, and the DTF component is not expected to be sensitive to radioactive iodine. External radiotherapy, non-steroidal anti-inflammatory drugs, tyrosine kinase inhibitors and chemotherapy have also been used in selected cases. Due to the rarity of these tumors and the lack of specific treatment guidelines, management should be discussed in a multidisciplinary team

Deep Markov Random Field for Image Modeling

Markov Random Fields (MRFs), a formulation widely used in generative image modeling, have long been plagued by the lack of expressive power. This issue is primarily due to the fact that conventional MRFs formulations tend to use simplistic factors to capture local patterns. In this paper, we move beyond such limitations, and propose a novel MRF model that uses fully-connected neurons to express the complex interactions among pixels. Through theoretical analysis, we reveal an inherent connection between this model and recurrent neural networks, and thereon derive an approximated feed-forward network that couples multiple RNNs along opposite directions. This formulation combines the expressive power of deep neural networks and the cyclic dependency structure of MRF in a unified model, bringing the modeling capability to a new level. The feed-forward approximation also allows it to be efficiently learned from data. Experimental results on a variety of low-level vision tasks show notable improvement over state-of-the-arts.Comment: Accepted at ECCV 201

Biological Soil Crusts as Modern Analogues for the Archean Continental Biosphere: Insights from Carbon and Nitrogen Isotopes

Stable isotope signatures of elements related to life such as carbon and nitrogen can be powerful biomarkers that provide key information on the biological origin of organic remains and their paleoenvironments. Marked advances have been achieved in the last decade in our understanding of the coupled evolution of biological carbon and nitrogen cycling and the chemical evolution of the early Earth thanks, in part, to isotopic signatures preserved in fossilized microbial mats and organic matter of marine origin. However, the geologic record of the early continental biosphere, as well as its evolution and biosignatures, is still poorly constrained. Following a recent report of direct fossil evidence of life on land at 3.22 Ga, we compare here the carbon and nitrogen isotopic signals of this continental Archean biosphere with biosignatures of cyanobacteria biological soil crusts (cyanoBSCs) colonizing modern arid environments. We report the first extended δ13C and δ15N data set from modern cyanoBSCs and show that these modern communities harbor specific isotopic biosignatures that compare well with continental Archean organic remains. We therefore suggest that cyanoBSCs are likely relevant analogues for the earliest continental ecosystems. As such, they can provide key information on the timing, extent, and possibly mechanism of colonization of the early Earth's emergent landmasses

Regulation of Motor Function and Behavior by Atypical Chemokine Receptor 1

The final publication is available at Springer via http://dx.doi.org/10.1007/s10519-014-9665-7Atypical Chemokine Receptor 1 (ACKR1), previously known as the Duffy Antigen Receptor for Chemokines, stands out among chemokine receptors for its high selective expression on Purkinje cells of the cerebellum, consistent with the ability of ACKR1 ligands to activate Purkinje cells in vitro. Nevertheless, evidence for ACKR1 regulation of brain function in vivo has been lacking. Here we demonstrate that Ackr1−/− mice have markedly impaired balance and ataxia when placed on a rotating rod and increased tremor when injected with harmaline, a drug that induces whole-body tremor by activating Purkinje cells. Ackr1−/− mice also exhibited impaired exploratory behavior, increased anxiety-like behavior and frequent episodes of marked hypoactivity under low-stress conditions. The behavioral phenotype of Ackr1−/− mice was the opposite of the phenotype occurring in mice with cerebellar degeneration and the defects persisted when Ackr1 was deficient only on non-hematopoietic cells. We conclude that normal motor function and behavior depend in part on negative regulation of Purkinje cell activity by Ackr1

Urban planning for healthy cities a review of the progress of the european healthy cities programme

The purpose of this paper is to evaluate the progress made by European cities in relation to Healthy Urban Planning (HUP) during Phase IV of the World Health Organization's Healthy Cities programme (2003-2008). The introduction sets out the general principle of HUP, identifying three levels or phases of health and planning integration. This leads on to a more specific analysis of the processes and substance of HUP, which provide criteria for assessment of progress. The assessment itself relies on two sources of data provided by the municipalities: the Annual Review Templates (ARTs) 2008 and the response to the Phase IV General Evaluation Questionnaire. The findings indicate that the evidence from different sources and questions in different sections are encouragingly consistent. The number of cities achieving a good level of understanding and activity inHUP has risen very substantially over the period. In particular, those achieving effective strategic integration of health and planning have increased. A key challenge for the future will be to develop planning frameworks which advance public health concerns in a spatial policy context driven often by market forces. A health in all policies approach could be valuable. © 2012 The New York Academy of Medicine

The homotopy type of the loops on (n−1)(n-1)-connected (2n+1)(2n+1)-manifolds

For $n\geq 2$ we compute the homotopy groups of $(n-1)$-connected closed manifolds of dimension $(2n+1)$. Away from the finite set of primes dividing the order of the torsion subgroup in homology, the $p$-local homotopy groups of $M$ are determined by the rank of the free Abelian part of the homology. Moreover, we show that these $p$-local homotopy groups can be expressed as a direct sum of $p$-local homotopy groups of spheres. The integral homotopy type of the loop space is also computed and shown to depend only on the rank of the free Abelian part and the torsion subgroup.Comment: Trends in Algebraic Topology and Related Topics, Trends Math., Birkhauser/Springer, 2018. arXiv admin note: text overlap with arXiv:1510.0519