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Peptide-directed crystal growth modification in the formation of ZnO
Biomolecule-mediated synthesis is fascinating in terms of the level of control and the intricate hierarchical structures of the materials that can be produced. In this study we compare the behavior of a phage display identified peptide, EAHVMHKVAPRP (EM-12) with that of a mutant peptide EAHVCHKVAPRP (EC-12), having additional complexation capability, on the formation of ZnO from solution. The synthesis conditions (Zn(CH3COO)2–NH3 hydrothermal method at 50 °C) were chosen to generate rod-shaped ZnO via layered basic zinc salts (LBZs) as intermediates. Both peptides affected the crystal formation process by moderating the amount of Zn2+ ions in solution (EC12 having a greater effect than EM12) but only EC12 was shown to interact with the solid phase(s) formed during the reaction. Depending on the peptide concentration used, EM-12 was shown to delay and/or suppress ZnO formation. In contrast, additions of EC-12, although leading to the retention of higher levels of Zn2+ ions in solution did not similarly delay the transformation of the intermediate phases to ZnO but were found to dramatically modify the morphology of ZnO crystallites with mushroom shaped crystals being formed. From the results of detailed materials characterization and changes in the morphology observed, the interactions between the peptide(s) and solution and solid state species present during the process of ZnO crystal formation in the presence of EM-12 and EC-12 are proposed
Storage protein profiles in Spanish and runner market type peanuts and potential markers
BACKGROUND: Proteomic analysis has proven to be the most powerful method for describing plant species and lines, and for identification of proteins in complex mixtures. The strength of this method resides in high resolving power of two-dimensional electrophoresis (2-DE), coupled with highly sensitive mass spectrometry (MS), and sequence homology search. By using this method, we might find polymorphic markers to differentiate peanut subspecies. RESULTS: Total proteins extracted from seeds of 12 different genotypes of cultivated peanut (Arachis hypogaea L.), comprised of runner market (A. hypogaea ssp. hypogaea) and Spanish-bunch market type (A. hypogaea ssp. fastigiata), were separated by electrophoresis on both one- and two-dimensional SDS-PAGE gels. The protein profiles were similar on one-dimensional gels for all tested peanut genotypes. However, peanut genotype A13 lacked one major band with a molecular weight of about 35 kDa. There was one minor band with a molecular weight of 27 kDa that was present in all runner peanut genotypes and the Spanish-derivatives (GT-YY7, GT-YY20, and GT-YY79). The Spanish-derivatives have a runner-type peanut in their pedigrees. The 35 kDa protein in A13 and the 27 kDa protein in runner-type peanut genotypes were confirmed on the 2-D SDS-PAGE gels. Among more than 150 main protein spots on the 2-D gels, four protein spots that were individually marked as spots 1–4 showed polymorphic patterns between runner-type and Spanish-bunch peanuts. Spot 1 (ca. 22.5 kDa, pI 3.9) and spot 2 (ca. 23.5 kDa, pI 5.7) were observed in all Spanish-bunch genotypes, but were not found in runner types. In contrast, spot 3 (ca. 23 kDa, pI 6.6) and spot 4 (ca. 22 kDa, pI 6.8) were present in all runner peanut genotypes but not in Spanish-bunch genotypes. These four protein spots were sequenced. Based on the internal and N-terminal amino acid sequences, these proteins are isoforms (iso-Ara h3) of each other, are iso-allergens and may be modified by post-translational cleavage. CONCLUSION: These results suggest that there may be an association between these polymorphic storage protein isoforms and peanut subspecies fastigiata (Spanish type) and hypogaea (runner type). The polymorphic protein peptides distinguished by 2-D PAGE could be used as markers for identification of runner and Spanish peanuts
The FANCD2-FANCI complex is recruited to DNA interstrand crosslinks before monoubiquitination of FANCD2
The Fanconi Anemia (FA) pathway is important for the repair of DNA interstrand
crosslinks (ICL). The FANCD2-FANCI complex is central to the pathway, and localizes
to ICLs dependent on its monoubiquitination. It has remained elusive whether the
complex is recruited before or after the critical monoubiquitination. Here we report the
first structural insight into the human FANCD2-FANCI complex by obtaining the cryo-
EM structure. The complex contains an inner cavity, large enough to accommodate a
double stranded DNA helix, as well as a protruding Tower domain. Disease-causing
mutations in the Tower domain is observed in several FA patients. Our work reveals that
recruitment of the complex to a stalled replication fork serves as the trigger for the
activating monoubiquitination event. Taken together, our results uncover the mechanism
of how the FANCD2-FANCI complex activates the FA pathway, and explains the
underlying molecular defect in FA patients with mutations in the Tower domain
The Carbon_h-Factor: Predicting Individuals' Research Impact at Early Stages of Their Career
Assessing an individual's research impact on the basis of a transparent algorithm is an important task for evaluation and comparison purposes. Besides simple but also inaccurate indices such as counting the mere number of publications or the accumulation of overall citations, and highly complex but also overwhelming full-range publication lists in their raw format, Hirsch (2005) introduced a single figure cleverly combining different approaches. The so-called h-index has undoubtedly become the standard in scientometrics of individuals' research impact (note: in the present paper I will always use the term “research impact” to describe the research performance as the logic of the paper is based on the h-index, which quantifies the specific “impact” of, e.g., researchers, but also because the genuine meaning of impact refers to quality as well). As the h-index reflects the number h of papers a researcher has published with at least h citations, the index is inherently positively biased towards senior level researchers. This might sometimes be problematic when predictive tools are needed for assessing young scientists' potential, especially when recruiting early career positions or equipping young scientists' labs. To be compatible with the standard h-index, the proposed index integrates the scientist's research age (Carbon_h-factor) into the h-index, thus reporting the average gain of h-index per year. Comprehensive calculations of the Carbon_h-factor were made for a broad variety of four research-disciplines (economics, neuroscience, physics and psychology) and for researchers performing on three high levels of research impact (substantial, outstanding and epochal) with ten researchers per category. For all research areas and output levels we obtained linear developments of the h-index demonstrating the validity of predicting one's later impact in terms of research impact already at an early stage of their career with the Carbon_h-factor being approx. 0.4, 0.8, and 1.5 for substantial, outstanding and epochal researchers, respectively
SSN: Shape Signature Networks for Multi-class Object Detection from Point Clouds
Multi-class 3D object detection aims to localize and classify objects of
multiple categories from point clouds. Due to the nature of point clouds, i.e.
unstructured, sparse and noisy, some features benefit-ting multi-class
discrimination are underexploited, such as shape information. In this paper, we
propose a novel 3D shape signature to explore the shape information from point
clouds. By incorporating operations of symmetry, convex hull and chebyshev
fitting, the proposed shape sig-nature is not only compact and effective but
also robust to the noise, which serves as a soft constraint to improve the
feature capability of multi-class discrimination. Based on the proposed shape
signature, we develop the shape signature networks (SSN) for 3D object
detection, which consist of pyramid feature encoding part, shape-aware grouping
heads and explicit shape encoding objective. Experiments show that the proposed
method performs remarkably better than existing methods on two large-scale
datasets. Furthermore, our shape signature can act as a plug-and-play component
and ablation study shows its effectiveness and good scalabilityComment: Code is available at https://github.com/xinge008/SS
Universal scaling relation in high-temperature superconductors
Scaling laws express a systematic and universal simplicity among complex
systems in nature. For example, such laws are of enormous significance in
biology. Scaling relations are also important in the physical sciences. The
seminal 1986 discovery of high transition-temperature (high-T_c)
superconductivity in cuprate materials has sparked an intensive investigation
of these and related complex oxides, yet the mechanism for superconductivity is
still not agreed upon. In addition, no universal scaling law involving such
fundamental properties as T_c and the superfluid density \rho_s, a quantity
indicative of the number of charge carriers in the superconducting state, has
been discovered. Here we demonstrate that the scaling relation \rho_s \propto
\sigma_{dc} T_c, where the conductivity \sigma_{dc} characterizes the
unidirectional, constant flow of electric charge carriers just above T_c,
universally holds for a wide variety of materials and doping levels. This
surprising unifying observation is likely to have important consequences for
theories of high-T_c superconductivity.Comment: 11 pages, 2 figures, 2 table
3D geometric modelling of discontinuous fibre composites using a force-directed algorithm
A geometrical modelling scheme is presented to produce representative architectures for discontinuous fibre composites, enabling downstream modelling of mechanical properties. The model generates realistic random fibre architectures containing high filament count bundles (>3k) and high (~50%) fibre volume fractions. Fibre bundles are modelled as thin shells using a multi-dimension modelling strategy, in which fibre bundles are distributed and compacted to simulate pressure being applied from a matched mould tool. FE simulations are performed to benchmark the in-plane mechanical properties obtained from the numerical model against experimental data, with a detailed study presented to evaluate the tensile properties at various fibre volume fractions and specimen thicknesses. Tensile modulus predictions are in close agreement (less than 5% error) with experimental data at volume fractions below 45%. Ultimate tensile strength predictions are within 4.2% of the experimental data at volume fractions between 40%-55%. This is a significant improvement over existing 2D modelling approaches, as the current model offers increased levels of fidelity, capturing dominant failure mechanisms and the influence of out-of-plane fibres
Effect of prolonged HAART on oral colonization with Candida and candidiasis
BACKGROUND: Progressive cell-mediated immunodeficiency with decrease of CD4+ lymphocyte count to less than or equal to 200 cells/mm(3 )is a major risk factor for colonization with Candida species and development of candidiasis. Oropharyngeal candidiasis may occur in up to 90% of human immunodeficiency virus (HIV)-infected patients during the course of the disease. This study is to determine the effect of prolonged highly active antiretroviral therapy (HAART) on oropharyngeal colonization with Candida species and oral candidiasis. METHODS: A prospective, longitudinal follow-up study in HIV-infected patients receiving HAART. RESULTS: The mean CD4+ count increased from 232.5 to 316 cells/mm(3 )and the proportion of patients whose CD4+ count less than 200 cells/mm(3 )decreased from 50.0% to 28.9% (p = 0.0003) in patients receiving HAART for at least 2 years. The prevalence of oral candidiasis decreased from 10.6% to 2.1% (p = 0.004). The decrease in Candida colonization was less impressive, falling from 57.8% to 46.5 % (p = 0.06). Of the 142 patients enrolled in at least two surveys, 48 (33.8%) remained colonized with Candida and 42 (29.6%) remained negative. In the remaining 52 patients, 34 switched from culture positive to negative, and an increase in CD4+ lymphocytes was noted in 91.2% of them. Among the 18 patients who switched from culture negative to positive, 61.1% also demonstrated an increase in CD4+ lymphocyte count (p = 0.01). CONCLUSION: These findings indicate that HAART is highly effective in decreasing oral candidiasis in association with a rise in CD4+ lymphocyte counts, but only marginally effective in eliminating Candida from the oropharynx
Objective effect manifestation of pectus excavatum on load-stressed pulmonary function testing: a case report
Abstract Introduction Pectus excavatum is the most common congenital deformity of the anterior chest wall that, under certain conditions, may pose functional problems due to cardiopulmonary compromise and exercise intolerance. Case presentation We present the case of an otherwise physically-adept 21-year-old Chinese sportsman with idiopathic pectus excavatum, whose symptoms manifested only on bearing a loaded body vest and backpack during physical exercise. Corroborative objective evidence was obtained via load-stressed pulmonary function testing, which demonstrated restrictive lung function. Conclusion This report highlights the possible detrimental synergism of thoracic load stress and pectus excavatum on cardiopulmonary function. Thoracic load-stressed pulmonary function testing provides objective evidence in support of such a synergistic relationship.</p
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