High resolution X-ray computed tomographic (CT) images of chondrites and a chondrule

In order to study internal textures of meteorites, images were obtained by X-ray computer tomography (CT). This combined high resolution X-ray radiography and computer tomography system belongs to the so-called third generation type with a micro-focus X-ray source and a linear CCD detector with 2048 elements. This allows a spacial resolution of a few μm in the images. Samples examined include the Moorabie meteorite (L3), Allende meteorite (CV3), and a chondrule removed from Allende meteorite. In images, Fe-Ni alloy, troilite, and silicates can be distinguished clearly, and chondrules can be resolved from their Fe-rich rims in Moorabie meteorite. In Allende Fe-Ni alloy, pentlandite, and silicates can be distinguished, and chondrules, CAI\u27s, and matrix can be recognized. Many euhedral crystals, probably olivine and/or pyroxene, were identified in a chondrule, suggesting that the chondrule has a porphyritic texture. In addition to minerals or their assemblages, holes can be identified by the X-ray CT method and were found in chondrules in Allende

Bias amplification in the g-computation algorithm for time-varying treatments: a case study of industry payments and prescription of opioid products

BACKGROUND: It is often challenging to determine which variables need to be included in the g-computation algorithm under the time-varying setting. Conditioning on instrumental variables (IVs) is known to introduce greater bias when there is unmeasured confounding in the point-treatment settings, and this is also true for near-IVs which are weakly associated with the outcome not through the treatment. However, it is unknown whether adjusting for (near-)IVs amplifies bias in the g-computation algorithm estimators for time-varying treatments compared to the estimators ignoring such variables. We thus aimed to compare the magnitude of bias by adjusting for (near-)IVs across their different relationships with treatments in the time-varying settings. METHODS: After showing a case study of the association between the receipt of industry payments and physicians' opioid prescribing rate in the US, we demonstrated Monte Carlo simulation to investigate the extent to which the bias due to unmeasured confounders is amplified by adjusting for (near-)IV across several g-computation algorithms. RESULTS: In our simulation study, adjusting for a perfect IV of time-varying treatments in the g-computation algorithm increased bias due to unmeasured confounding, particularly when the IV had a strong relationship with the treatment. We also found the increase in bias even adjusting for near-IV when such variable had a very weak association with unmeasured confounders between the treatment and the outcome compared to its association with the time-varying treatments. Instead, this bias amplifying feature was not observed (i.e., bias due to unmeasured confounders decreased) by adjusting for near-IV when it had a stronger association with the unmeasured confounders (≥0.1 correlation coefficient in our multivariate normal setting). CONCLUSION: It would be recommended to avoid adjusting for perfect IV in the g-computation algorithm to obtain a less biased estimate of the time-varying treatment effect. On the other hand, it may be recommended to include near-IV in the algorithm unless their association with unmeasured confounders is very weak. These findings would help researchers to consider the magnitude of bias when adjusting for (near-)IVs and select variables in the g-computation algorithm for the time-varying setting when they are aware of the presence of unmeasured confounding

Hydrothermally synthesized poorly-crystalline binary oxides with ZrW2O8 composition : preparation, structural analysis, and catalytic activity for the alkylation of anisole with benzyl alcohol

Hydrothermally synthesized poorly-crystalline metastable Zr–W binary hydroxide (W/Zr = 2), after calcination, was confirmed to be a strong solid acid catalyst to promote the alkylation of anisole with benzyl alcohol. The preparation conditions, structure of the as-prepared catalysts and the calcined hydroxides were investigated using XRD, nitrogen adsorption isotherms, TG-DTA, and XANES/EXAFS techniques. The crystalline phase was controlled by the hydrochloric acid concentration used for preparing a mother gel, and 5–9 M HCl was suitable for preparing the active phase. The tungsten species exists as a six-valent WO6 distorted octahedron connected with the ZrO7 unit via corner-sharing linkages. The incompleteness of the network structure is suggested to be responsible for the solid acidity

Complete nucleotide sequence of the Cryptomeria japonica D. Don. chloroplast genome and comparative chloroplast genomics: diversified genomic structure of coniferous species

<p>Abstract</p> <p>Background</p> <p>The recent determination of complete chloroplast (cp) genomic sequences of various plant species has enabled numerous comparative analyses as well as advances in plant and genome evolutionary studies. In angiosperms, the complete cp genome sequences of about 70 species have been determined, whereas those of only three gymnosperm species, <it>Cycas taitungensis</it>, <it>Pinus thunbergii</it>, and <it>Pinus koraiensis </it>have been established. The lack of information regarding the gene content and genomic structure of gymnosperm cp genomes may severely hamper further progress of plant and cp genome evolutionary studies. To address this need, we report here the complete nucleotide sequence of the cp genome of <it>Cryptomeria japonica</it>, the first in the Cupressaceae sensu lato of gymnosperms, and provide a comparative analysis of their gene content and genomic structure that illustrates the unique genomic features of gymnosperms.</p> <p>Results</p> <p>The <it>C. japonica </it>cp genome is 131,810 bp in length, with 112 single copy genes and two duplicated (<it>trn</it>I-CAU, <it>trn</it>Q-UUG) genes that give a total of 116 genes. Compared to other land plant cp genomes, the <it>C. japonica </it>cp has lost one of the relevant large inverted repeats (IRs) found in angiosperms, fern, liverwort, and gymnosperms, such as <it>Cycas </it>and <it>Gingko</it>, and additionally has completely lost its <it>trn</it>R-CCG, partially lost its <it>trn</it>T-GGU, and shows diversification of <it>acc</it>D. The genomic structure of the <it>C. japonica </it>cp genome also differs significantly from those of other plant species. For example, we estimate that a minimum of 15 inversions would be required to transform the gene organization of the <it>Pinus thunbergii </it>cp genome into that of <it>C. japonica</it>. In the <it>C. japonica </it>cp genome, direct repeat and inverted repeat sequences are observed at the inversion and translocation endpoints, and these sequences may be associated with the genomic rearrangements.</p> <p>Conclusion</p> <p>The observed differences in genomic structure between <it>C. japonica </it>and other land plants, including pines, strongly support the theory that the large IRs stabilize the cp genome. Furthermore, the deleted large IR and the numerous genomic rearrangements that have occurred in the <it>C. japonica </it>cp genome provide new insights into both the evolutionary lineage of coniferous species in gymnosperm and the evolution of the cp genome.</p

High-grade Glioma Masquerading as a Small Cerebral Hemorrhage: A Case Report

We report a rare case of a high-grade glioma masquerading as a small subcortical hemorrhage. A 71-year-old woman came to a local hospital with sudden right upper extremity numbness. Computed tomography revealed a small subcortical hemorrhage with faint perifocal edema in the left postcentral gyrus. Conservative treatment was initiated, and she was discharged from the hospital with no neurological deficits. Six months later after discharge, she suffered an acute partial seizure of the right upper extremity. Magnetic resonance imaging with gadolinium demonstrated a ring-enhancing mass surrounded by severe perifocal edema in the hemorrhagic scar. We performed complete resection of the tumor, and the histological diagnosis was anaplastic oligodendroglioma. The diagnosis of a high-grade glioma was delayed due to intratumoral hemorrhages mimicking a small subcortical hemorrhage; consequently, we suspected the hemorrhage was induced by cerebral amyloid angiopathy. It may be important to repeat radiological follow up, if necessary, and to maintain clinical observance of possible intracranial neoplasm, even when the hemorrhage is small, particularly when the cause of bleeding is unknown

Seronegative Oligoarthritis Preceding Psoriasis by 9.5 Years

We report a case of psoriatic arthritis where oligoarthritis preceded the skin lesions. A 57-year-old man complained of left third-finger pain. Laboratory examinations were negative for anti-cyclic citrullinated peptide antibodies and rheumatoid factor; he was treated for suspected rheumatoid arthritis. Six years later, X-ray revealed enthesitis of his fingers and wrist joint. At 9.5 years after the initial visit, skin lesions appeared in the left auricular region and buttock and dermatopathology findings indicated psoriasis vulgaris. The final diagnosis was psoriatic arthritis. In cases of seronegative oligoarthritis, psoriatic arthritis must be considered because some patients demonstrate osteoarticular lesions preceding skin lesions