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The origin of diamond in ureilites has been frequently debated. We investigated carbon phase assemblages (CPAs) in five ureilitic samples of the brecciated asteroid 2008 TC3, found within the Almahata Sitta (AHS) strewn field, by transmission electron microscopy, Raman spectroscopy, synchrotron X‐ray diffraction, and cathodoluminescence. Samples MS‐MU 006, MS‐187, and MS‐170, are of low to moderate shock degree (U‐S2 and U‐S3), and samples MS‐MU 027 (U‐S4) and MS‐MU 045 (U‐S5) have a higher shock degree. In MS‐MU 006 and MS‐187, we did not find any diamond grains. MS‐170 contains disordered and distorted graphite with diamond grains up to 12 μm in size and containing inclusions of Fe,Ni‐metal, FeS, Fe‐phosphide, and Cr,Fe‐oxide. These diamond grains formed under relatively low (5–15 GPa) shock pressures through a catalytic process in the presence of a Fe,Ni,Cr,S,P‐rich melt. The highly shocked and fine‐grained ureilites MS‐MU 027 and MS‐MU 045 have three different types of CPAs, namely a nanopolycrystalline assemblage of diamond and defect‐rich diamond/lonsdaleite, disordered and distorted graphite, and polycrystalline diamond with abundant Fe‐rich mineral inclusions. The CPAs that have only diamond and planar defect‐rich diamond (e.g., MS‐MU 027) most likely formed through martensitic transformation of graphite to diamond and lonsdaleite at >15 GPa and >2000 K. The assemblage of diamond, defect‐rich diamond, and disordered and distorted graphite (e.g., MS‐MU 045) formed by martensitic transformation of graphite to diamond and lonsdaleite, followed by back‐transformation to disordered graphite. We did not find any conclusive evidence to support the formation of diamond grains under high static pressure. [ABSTRACT FROM AUTHOR]

ABSTRACT This article presents quad-directional magneto-dielectric (MD) resonator antenna configuration, designed using two different MD materials with stack configuration. These materials have been designed such that their temperature coefficient is approximately zero. The microwave dielectric constant (εr) and permeability (μr) of both materials are calculated by Nicholson-Ross-Weir conversion technique and found to be 8.02, 1.64 and 10.47, 1.52, respectively. The designed antenna can radiates in four directions simultaneously at the resonant frequency of 5.84 GHz. The beam shaping has been achieved using single feed and this property can be utilized for the angle diversity. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:62-64, 2016 [ABSTRACT FROM AUTHOR]

Introduction: With up to 8.55 wt% carbon [1], ureilites are the most carbon-rich meteorites. Graphite is the most abundant carbon allotrope, typically located in interstitial sites between silicate grains. Main group ureilites have experienced varying degrees of shock processing, altering their texture [e.g., 2]. Understanding the carbon mineralogy is crucial for interpretations regarding the processing of the ureilite parent body (UPB) [e.g., 3, 4], the debated origin of diamonds [e.g., 5-7], and graphite-based geothermometry [e.g., 8]. Methods: Raman spectra were obtained in 14 samples with a IDR-Micro-532 micro-Raman spectrometer. A Nd:YAG laser with a wavelength of 532 nm, and a laser power of 1.1 mW on the sample surface was used. An analysis consisted of a measurement time of 10 s with 5 accumulations. The statistical evaluation included baseline subtraction, peak identification, and the extraction of selected parameters (e.g., G band position and FWHM). Results: Based on the texture, the investigated samples can be catergorized into coarse-grained and fine-grained ureilites. The G band positions of graphite in coarse-grained ureilites cluster in a confined range between 1580-1583 cm-1, corresponding to crystalline graphite. Shock indicators in olivine [cf. 9] suggest that these coarsegrained samples have experienced relatively low shock pressures up to 15-20 GPa. In contrast, the Raman signatures obtained in fine-grained ureilties show a large variability and significantly higher G band positions/FWHMs, which can be attributed to a high degree of crystallographic disorder. Overall, the G band position and the G band FWHM show a nearly linear positive correlation. Discussion: A strong correlation between the texture (coarse-grained and fine-grained) and the Raman signature of graphite (crystalline graphite and disordered graphite/poorly graphitized carbon) can be observed. This raises the question, which underlying process is responsible for the increased crystallographic disorder present in graphite in fine-grained ureilites? One key observation is that the carbon phases in fine-grained ureilites often occur in textural units, which resemble the shape of graphite grains found in coarse-grained ureilites. This suggests that graphite was highly crystalline in the first place, and was subsequently replaced/modified by parent body processing. The resulting carbon phases in fine-grained ureilites are considerably more diverse compared to coarse-grained ureilites, where graphite is by far the dominant carbon allotrope. Most likely, the underlying mechanism is related to the same process, which lead to mosaicism and the visible fragmentation of silicates. In this case, the process should be related to post-accretionary shock, induced by high velocity impacts. Yet, it is unclear whether disordered graphite is a direct product of the transformation from highly crystalline graphite, or if disordered graphite might also result from the back-transformation of diamond. Conclusion: The parent body processing of ureilties has a significant effect on the carbon mineralogy. The G band parameters of graphite in finegrained and coarse-grained ureilites form two clusters, which plot on a nearly linear trend reflecting crystallographic order. Presumably, the underlying process is related to the post-accretionary shock processing of the ureilite parent body. [ABSTRACT FROM AUTHOR]

The article focuses on a study which described the effect of neutron irradiation on jute fiber. It cites the ability of fast neutrons to produce dense ionization at deep levels in materials as a significant aspect of neutron irradiation. Results of the study showed that irradiation has a negative effect on the thermal stability of fibers. The study also found a decrease in the mechanical properties of the fibers following irradiation.

Fibrotic diseases cause organ failure that lead to ~45% of all deaths in the United States. Activated macrophages stimulate fibrosis by secreting cytokines that induce fibroblasts to synthesize collagen and extracellular matrix proteins. Although suppression of macrophage-derived cytokine production can halt progression of fibrosis, therapeutic agents that prevent release of these cytokines (e.g., TLR7 agonists) have proven too toxic to administer systemically. Based on the expression of folate receptor β solely on activated myeloid cells, we have created a folate-targeted TLR7 agonist (FA-TLR7-54) that selectively accumulates in profibrotic macrophages and suppresses fibrosis-inducing cytokine production. We demonstrate that FA-TLR7-54 reprograms M2-like fibrosis-inducing macrophages into fibrosis-suppressing macrophages, resulting in dramatic declines in profibrotic cytokine release, hydroxyproline biosynthesis, and collagen deposition, with concomitant increases in alveolar airspaces. Although nontargeted TLR7-54 is lethal at fibrosis-suppressing doses, FA-TLR7-54 halts fibrosis without evidence of toxicity. Taken together, FA-TLR7-54 is shown to constitute a novel and potent approach for treating fibrosis without causing dose-limiting systemic toxicities., (© 2020 The Authors. Published under the terms of the CC BY 4.0 license.)

Malaria is the most lethal and debilitating disease caused by the protozoan parasite Plasmodium worldwide. The most severe forms of disease and the incidence rates of mortality are associated with P. falciparum infections. With the identification of disease source and symptoms, many chemical entities were developed naturally and synthetically for administration as a potential antimalarial drug. The major classes of approved antimalarial drugs that are governed as first-line treatment in tropical and subtropical areas include quinolines, naphthoquinones, antifolates, 8-aminoquinolines, and endoperoxides. However, the efficacy of antimalarial drugs has decreased due to ongoing multidrug resistance problem to current drugs. With increasing resistance to the current antimalarial artemisinin and its combination therapies, malaria prophylaxis has declined gradually. New-generation antimalarial and novel drug target are required to check the incidence of malaria resistance. This review summarizes the emergence of multidrug resistance to known antimalarial and the development of new antimalarial to resolve drug resistance condition. Few essential proteins are also discussed that can be considered as novel drug target against malaria in future., (© 2019 John Wiley & Sons A/S.)