Paleozoic geology of the Round Mountain area, Blanco quadrangle, Texas

Geological Science

Likelihood inference for particle location in fluorescence microscopy

We introduce a procedure to automatically count and locate the fluorescent particles in a microscopy image. Our procedure employs an approximate likelihood estimator derived from a Poisson random field model for photon emission. Estimates of standard errors are generated for each image along with the parameter estimates, and the number of particles in the image is determined using an information criterion and likelihood ratio tests. Realistic simulations show that our procedure is robust and that it leads to accurate estimates, both of parameters and of standard errors. This approach improves on previous ad hoc least squares procedures by giving a more explicit stochastic model for certain fluorescence images and by employing a consistent framework for analysis.Comment: Published in at http://dx.doi.org/10.1214/09-AOAS299 the Annals of Applied Statistics (http://www.imstat.org/aoas/) by the Institute of Mathematical Statistics (http://www.imstat.org

Recovering facial shape using a statistical model of surface normal direction

In this paper, we show how a statistical model of facial shape can be embedded within a shape-from-shading algorithm. We describe how facial shape can be captured using a statistical model of variations in surface normal direction. To construct this model, we make use of the azimuthal equidistant projection to map the distribution of surface normals from the polar representation on a unit sphere to Cartesian points on a local tangent plane. The distribution of surface normal directions is captured using the covariance matrix for the projected point positions. The eigenvectors of the covariance matrix define the modes of shape-variation in the fields of transformed surface normals. We show how this model can be trained using surface normal data acquired from range images and how to fit the model to intensity images of faces using constraints on the surface normal direction provided by Lambert's law. We demonstrate that the combination of a global statistical constraint and local irradiance constraint yields an efficient and accurate approach to facial shape recovery and is capable of recovering fine local surface details. We assess the accuracy of the technique on a variety of images with ground truth and real-world images

Mosquitos Associated with Equine West Nile Virus Cases in Southeastern Georgia

Mosquito populations associated with equine and avian cases of West Nile Virus infections in five counties in southeastern Georgia were sampled in 2003 and 2004. More than 10,500 mosquitoes representing over 20 species were collected at 25 sites using light traps and vacuum aspirators. Of these, 8,500 mosquitoes were tested for the presence of West Nile Virus, Eastern Equine Encephalitis Virus, and Saint Louis Encephalitis Virus in 411 separate pools of 1-50 mosquitoes. No virus positive mosquitoes were detected. Blood meals from 377 engorged specimens caught at these sites were identified as of mammalian, avian, or reptile/amphibian origin using serological methods. Overall, results suggest that Culex nigripalpus was the most likely vector of West Nile Virus at rural sites in southeastern Georgia, because of the relative abundance of this species and its pattern of blood feeding on both birds and mammals

The Parkinson’s Gene VPS13C Encodes an ER-Lysosome Lipid Transfer Protein Linking Lysosomal Lipid Homeostasis and cGAS/STING-Mediated Innate Immunity

Biallelic loss-of-function mutations in VPS13C cause early-onset Parkinson’s Disease (PD), and the VPS13C locus is a GWAS hit for sporadic PD risk. VPS13C is a member of the VPS13 family, which in humans contains three other proteins, VPS13A, VPS13B, and VPS13D, all with ties to neurological diseases. Mutations in VPS13A cause chorea-acanthocytosis a Huntington’s like syndrome with dysmorphic erythrocytes, mutations in VPS13B cause the neurodevelopmental disorder Cohen syndrome, and mutations in VPS13D cause spastic ataxia with varying presentation. The molecular function of these proteins, why their loss cause neurological diseases, and why they are each associated with distinct diseases despite their homology have all been open questions. In yeast, the single Vps13 protein localizes to contact sites between the mitochondria and vacuole, the yeast lysosome, and at the nuclear-vacuolar junction (NVJ), where multiple lines of indirect evidence has hinted that it may play a role in lipid transfer between these organelles. To understand whether human VPS13 proteins have diverged in their subcellular localization, we employed a combination of light and electron microscopy to demonstrate that VPS13A localizes to contact sites between the endoplasmic reticulum (ER) and mitochondria, while VPS13C localizes to contact sites between the ER and late endosomes/lysosomes. Both proteins also share a localization at ER-lipid droplet contact sites. We further show that the N-terminal portion of VPS13 forms a novel, tubular, hydrophobic cavity that can solubilize and transport glycerolipids between membranes. These findings identify VPS13 as a lipid transporter between the ER and other organelles, implicating defects in membrane lipid homeostasis in neurological disorders resulting from their mutations. Sequence and secondary structure similarity between the N-terminal portions of Vps13 and other proteins such as the autophagy protein ATG2 suggested lipid transport roles for these proteins as well, which has since been demonstrated. We next investigated the cellular phenotypes of VPS13C loss-of-function in an attempt to shed light on the pathophysiology of VPS13C-associated PD. We used CRISPR-Cas9 to generate VPS13C-knockout (VPS13CKO) HeLa cells. These cells have more lysosomes compared to WT, with accumulation of both membrane and luminal lysosomal proteins. These lysosomes have an altered lipid profile, including a substantial decrease in ether-linked phospholipids and an accumulation of di-22:6-BMP, a biomarker of the PD-associated leucine-rich repeat kinase 2 (LRRK2) G2019S mutation. In addition, the DNA-sensing cGAS/STING pathway, which was recently implicated in PD pathogenesis, is activated in these cells. This activation results from a combination of elevated mitochondrial DNA in the cytosol and a defect in the degradation of activated STING, a lysosome-dependent process. These results suggest a link between ER-lysosome lipid transfer and innate immune activation and place VPS13C in pathways relevant to PD pathogenesis. Further exploration of these pathways has the potential to yield new mechanistic understanding and novel therapeutic strategies for this debilitating illness

Linear Differential Constraints for Photo-polarimetric Height Estimation

In this paper we present a differential approach to photo-polarimetric shape estimation. We propose several alternative differential constraints based on polarisation and photometric shading information and show how to express them in a unified partial differential system. Our method uses the image ratios technique to combine shading and polarisation information in order to directly reconstruct surface height, without first computing surface normal vectors. Moreover, we are able to remove the non-linearities so that the problem reduces to solving a linear differential problem. We also introduce a new method for estimating a polarisation image from multichannel data and, finally, we show it is possible to estimate the illumination directions in a two source setup, extending the method into an uncalibrated scenario. From a numerical point of view, we use a least-squares formulation of the discrete version of the problem. To the best of our knowledge, this is the first work to consider a unified differential approach to solve photo-polarimetric shape estimation directly for height. Numerical results on synthetic and real-world data confirm the effectiveness of our proposed method.Comment: To appear at International Conference on Computer Vision (ICCV), Venice, Italy, October 22-29, 201

PRODUCER ACCEPTANCE OF A NEW PEANUT MARKETING COOPERATIVE: A SURVEY OF GEORGIA PEANUT PRODUCERS

Market conduct has become an important issue for peanut farmers. Consolidation in the first buyer market, increased imports, and political uncertainty have increased peanut producers' marketing risks. The purpose of this paper was to examine demographic differences in peanut producers' perceptions of the current marketing environment as well as their attitudes towards new marketing institutions. A standard t-test revealed that producers growing more than 250 acres of peanuts, irrigating at least 50 percent of their peanuts, and producers located in Southwest Georgia were statistically more dissatisfied with the current marketing environment and significantly more receptive to forming a new generation peanut cooperative.Agribusiness, Crop Production/Industries,

A NEW GENERATION PEANUT COOPERATIVE IN GEORGIA: A BENEFIT-COST ANALYSIS

A survey of Georgia peanut producers revealed that the Southwest corner of Georgia could be targeted for a new generation peanut cooperative (FS 01-07). The objective of this study was to examine the feasibility of this option. Preliminary results revealed that this might be an economically feasible solution to peanut producers' marketing problems. The projected discounted benefit-cost ratios ranged from 1.9 to 1.4 over a ten-year period.Agribusiness, Crop Production/Industries,