A determination of the mean values of the #19 test for various age levels and a comparison to those of Donders and Duane

The purpose of this study is to determine the mean value and variability of the amplitude of accommodation as designated by the number nineteen finding in the standard analytical routine and to compare these to those means of Donders and Duane

Computer-Aided Detection of Pathologically Enlarged Lymph Nodes On Non-Contrast CT In Cervical Cancer Patients For Low-Resource Settings

The mortality rate of cervical cancer is approximately 266,000 people each year, and 70% of the burden occurs in Low- and Middle- Income Countries (LMICs). Radiation therapy is the primary modality for treatment of locally advanced cervical cancer cases. In the absence of high quality diagnostic imaging needed to identify nodal metastasis, many LMIC sites treat standard pelvic fields, failing to include node metastasis outside of the field and/or to boost lymph nodes in the abdomen and pelvis. The first goal of this project was to create a program which automatically identifies positive cervical cancer lymph nodes on non-contrast daily CT images, which are widely available in LMICs(1). A region of interest which is likely to contain the nodal volumes relevant for cervical cancer was defined on a single patient CT(2). This region was deformed onto new patients using an in-house, demons-based deformation software. Edge detection and erosion filtering were used to distinguish potential positive nodes from normal structures. Regions on adjacent slices were then connected into a potential nodal 3D-structure. To differentiate these 3D structures from normal tissues, eighty-six features were generated based on the shape and mean pixel values of the structures, and four classification ensemble methods were tested to differentiate the positive nodes from normal tissues. A cohort of fifty-eight MD Anderson cervical cancer patients with pathologically enlarged lymph nodes were used as a training-test set. Similarly, twenty MD Anderson cervical cancer patients were obtained as a validation set. They contained 154 and 35 pathologically enlarged lymph nodes, respectively. Model comparison led to the selection of the Adaboost ensemble model, utilizing 17 features. In the validation set, 60% of the clinically significant positive cervical cancer nodes were identified along with a false/true positive ratio of ~4:1. The entire process takes approximately 10/number-of-cores-minutes. Our findings demonstrated that our computer-aided detection model can assist in the identification of metastatic nodal disease where high quality diagnostic imaging is not readily available. By identifying these nodes, radiation treatment fields can be modified to include pathologically enlarged lymph nodes, which is an essential element to providing potentially curative radiotherapy for cervical cancer

HOW DO WE IDENTIFY MICRONYCTERIS (SCHIZONYCETRIS) SANBORNI SIMMONS, 1996 (CHIROPTERA, PHYLLOSTOMIDAE) RELIABLY AND WHERE WE CAN FIND THIS SPECIES IN BRAZIL?

Micronycteris is divided into four subgenera, Micronycteris, Leuconycteris, Xenoctenes, and Schizonycteris. The latter includes Micronycteris (Schizonycteris) minuta, Micronycteris (S.) schmidtorum, Micronycteris (S.) sanborni and Micronycteris (S.) yatesi. Little is known of the biology of M. (S.) sanborni, which is widely distributed in the dry forests of South America, but is known from only few sites. The scarcity of records of M. sanborni appears to be at least partly related to the difficulty of differentiating this species from the other members of the subgenus Schizonycteris. The present study identifies the key traits that distinguish this species from other Schizonycteris, reviews the geographic distribution of the species, and presents some notes on breeding patterns. Six new localities are presented for M. sanborni, and are analyzed together with those available in the literature, providing new insights into ecological and zoogeographic patterns. A number of the diagnostic features established by Simmons (1996) in the description of M. sanborni proved to have little taxonomic value, especially for the differentiation of M. minuta and M. yatesi, which it closely resembles. The primary external difference is the pure white color of the ventral pelage and the proportion of the white base (2/3-4/5) of the dorsal hair in M. sanborni, in contrast with dirty white or pale gray and a much shorter white base of the dorsal hair in the other species. A number of cranial traits are also important. The distributional data now indicate that M. sanborni occurs mainly in mesic and open areas, including disturbed habitats, in the Caatinga scrublands and the Cerrado savannas of northeastern Brazil, especially in areas with rocky outcrops. Micronycteris sanborni appears to be monoestrous, with births coinciding with the rainy season.Micronycteris está dividido em quatro subgêneros, Micronycteris, Leuconycteris, Xenoctenes e Schizonycteris. Este último inclui Micronycteris (Schizonycteris) minuta, Micronycteris (S.) schmidtorum, Micronycteris (S.) sanborni e Micronycteris (S.) yatesi. Atualmente pouco se sabe sobre a biologia de M. (S.) sanborni, a qual é amplamente distribuída pelas florestas secas da América do Sul, apesar de ser conhecida de apenas poucas localidades. A escassez de registros de M. sanborni parece está parcialmente relacionado a dificuldade de diferenciar esta espécie de outros membros do subgênero Schizonycteris. Dessa forma, o presente estudo visa identificar as características diagnósticas que distingue esta espécie dos outros Schizonycteris, revisar a distribuição geográfica dessa espécie e apresentar comentários sobre o seu padrão reprodutivo. Seis novas localidades são apresentadas aqui para M. sanborni e, juntas com as outras disponíveis na literatura, foram analisadas fornecendo novas abordagens sobre o padrão ecológico e zoogeográfico dessa espécie. Várias características diagnósticas estabelecidas por Simmones (1996) na descrição de M. sanborni mostraram-se de pouco valor taxonômico, especialmente para a diferenciação entre M. minuta e M. yatesi, das quais mais se assemelha. As principais diferenças externas são a coloração branco pura do ventre e a proporção da base branca (2/3-4/5) do pelo dorsal em M. sanborni, em contraste com a coloração branco sujo ou acinzentado e a base dorsal branca muito mais curta das outras espécies. Outras características cranianas mostraram-se também importantes para a diferenciação. Os dados de distribuição levantados indicam que M. sanborni ocorre principalmente em áreas mésicas e abertas, incluindo ambientes alterados, na Caatinga arbustiva e nas savanas do Cerrado do nordeste do Brasil, especialmente em áreas com afloramentos rochosos. Micronycteris sanborni parece ser monoéstrico, com os nascimentos coincidindo com a estação chuvosa

Phosphonopeptides Revisited, in an Era of Increasing Antimicrobial Resistance

Given the increase in resistance to antibacterial agents, there is an urgent need for the development of new agents with novel modes of action. As an interim solution, it is also prudent to reinvestigate old or abandoned antibacterial compounds to assess their efficacy in the context of widespread resistance to conventional agents. In the 1970s, much work was performed on the development of peptide mimetics, exemplified by the phosphonopeptide, alafosfalin. We investigated the activity of alafosfalin, di-alanyl fosfalin and β-chloro-L-alanyl-β-chloro-L-alanine against 297 bacterial isolates, including carbapenemase-producing Enterobacterales (CPE) (n = 128), methicillin-resistant Staphylococcus aureus (MRSA) (n = 37) and glycopeptide-resistant enterococci (GRE) (n = 43). The interaction of alafosfalin with meropenem was also examined against 20 isolates of CPE. The MIC50 and MIC90 of alafosfalin for CPE were 1 mg/L and 4 mg/L, respectively and alafosfalin acted synergistically when combined with meropenem against 16 of 20 isolates of CPE. Di-alanyl fosfalin showed potent activity against glycopeptide-resistant isolates of Enterococcus faecalis (MIC90; 0.5 mg/L) and Enterococcus faecium (MIC90; 2 mg/L). Alafosfalin was only moderately active against MRSA (MIC90; 8 mg/L), whereas β-chloro-L-alanyl-β-chloro-L-alanine was slightly more active (MIC90; 4 mg/L). This study shows that phosphonopeptides, including alafosfalin, may have a therapeutic role to play in an era of increasing antibacterial resistance

Getting lost in the matrix? On how the characteristics and arrangement of linear landscape elements influence ecological connectivity

Acknowledgements We would like to thank the Natural Environment Research Council and Natural England for providing the funding to conduct this study. We are also indebted to the work of Greta Bocedi in developing the RangeShifter platform prior to its implementation in this study. Funding This research was supported by the Natural Environment Research Council (NERC) [Grant No. NE/P009697/1]. Support was also received from Natural England (https://www.gov.uk/government/organisations/natural-england).Peer reviewedPublisher PD

Crystallization of a designed peptide from a molten globule ensemble

Backgound:The design of amino acid sequences that adopt a desired three-dimensional fold has been of keen interest over the past decade. However, the design of proteins that adopt unique conformations is still a considerable problem. Until very recently, all of the designed proteins that have been extensively characterized possess the hallmarks of the molten globular state. Molten globular intermediates have been observed in both equilibrium and kinetic protein folding/stability studies, and understanding the forces that determine compact non-native states is critical for a comprehensive understanding of proteins. This paper describes the solution and early solid state characterization of peptides that form molten globular ensembles.Results & Conclusions:Crystals diffracting to 3.5å resolution have been grown of a 16-residue peptide (α1A) designed to form a tetramer of α-helices. In addition, a closely related peptide, α1, has previously been shown to yield crystals that diffract to 1.2å resolution. The solution properties of these two peptides were examined to determine whether their well defined crystalline conformations were retained in solution. On the basis of an examination of their NMR spectra, sedimentation equilibria, thermal unfolding, and ANS binding, it is concluded that the peptides form α-helical aggregates with properties similar to those of the molten globule state. Thus, for these peptides, the process of crystallization bears many similarities to models of protein folding. Upon dissolution, the peptides rapidly assume compact molten globular states similar to the molten globule like intermediates that are formed at short times after refolding is initiated. Following a rate-determining nucleation step, the peptides crystallize into a single or a small number of conformations in a process that mimics the formation of native structure in proteins

Is there spin-charge separation in the 2D Hubbard and t-J models at low electronic densities?

The spin and density correlation functions of the two-dimensional Hubbard model at low electronic density $$ are calculated in the ground state by using the power method, and at finite temperatures by using the quantum Monte Carlo technique. Both approaches produce similar results, which are in close agreement with numerical and high temperature expansion results for the two-dimensional ${\rm t-J}$ model. Using perturbative approximations, we show that the examination of the density correlation function alone is not enough to support recent claims in the literature that suggested spin and charge separation in the low electronic density regime of the ${\rm t-J}$ model.Comment: 11 pages, tex, 3 figures upon request, NTHU - preprin

Simulation of Fixed– and Variable–Rate Application of Granular Materials

Research has shown that application errors exist with variable–rate technology (VRT) systems. Consequently, using prescription maps for economic and agronomic analyses can generate misleading results. The intent of this article was to develop and validate a spatial data model for generating “as–applied” maps to support the advancement of precision agriculture practices. Previous research modified ASAE Standard S341.2 to include a 2–D matrix of collection pans to assess fixed–rate and variable–rate (VR) deposition of granular fertilizers and agricultural lime from a spinner disc spreader. The “as–applied” spatial data model uses GIS functionality to generate “as–applied” surfaces by merging distribution patterns and a spatial field application file (FAF) into an “as–applied” surface representing the actual distribution of granular fertilizer or agricultural lime across a field. To validate the “as–applied” spatial data model, field studies were conducted by randomly placing collection pans across two fields. Murate of potash was then applied using a VR spinner spreader. The “as–applied” spatial data model was used to predict the amount of material each pan should have received. Comparisons were made between the actual and predicted application rates for two fields, with R2 values of 0.45 (field A) and 0.58 (field B) computed. However, R2 values of 0.16 (field A) and 0.21 (field B) were observed when comparing the actual application rates and prescription maps. These low R2 values indicated poor application by the spinner spreader but demonstrated that the “as–applied” model did a better job of representing the distribution of murate of potash when contrasted with the prescription maps. “As–applied” surfaces provide a means for evaluating fixed–rate and VR application of granular products while enhancing researchers’ ability to compare VR management approaches