Crab in Amber Reveals an Early Colonization of Nonmarine Environments During the Cretaceous

Amber fossils provide snapshots of the anatomy, biology, and ecology of extinct organisms that are otherwise inaccessible. The best-known fossils in amber are terrestrial arthropods—principally insects—whereas aquatic organisms are rarely represented. Here, we present the first record of true crabs (Brachyura) in amber—from the Cretaceous of Myanmar [~100 to 99 million years (Ma)]. The new fossil preserves large compound eyes, delicate mouthparts, and even gills. This modern-looking crab is nested within crown Eubrachyura, or “higher” true crabs, which includes the majority of brachyuran species living today. The fossil appears to have been trapped in a brackish or freshwater setting near a coastal to fluvio-estuarine environment, bridging the gap between the predicted molecular divergence of nonmarine crabs (~130 Ma) and their younger fossil record (latest Cretaceous and Paleogene, ~75 to 50 Ma) while providing a reliable calibration point for molecular divergence time estimates for higher crown eubrachyurans

Fate of Minus-Strand Templates and Replication Complexes Produced by a P23-Cleavage-Defective Mutant of Sindbis Virus▿

SIN2V is an engineered mutant Sindbis virus (SIN) that is unable to process the P23 cleavage site in polyproteins P123 and P1234 that are translated from the genome after its entry into cells. Unlike wild-type (wt) SIN, it caused minus strands to be made continuously and replication-transcription complex (RTC) activity to be unstable (R. Gorchakov, E. Frolova, S. Sawicki, S. Atasheva, D. Sawicki, and I. Frolov, J. Virol. 82:6218-6231, 2008). We examined further the effects of P23 on SIN RNA replication and RTC activity. Continuous minus-strand synthesis by SIN2V produced 250% of wt levels of minus strands but accumulated only 110% of wt levels (0.39 pg, or 2.7 × 104 molecules of double-stranded RNA per cell). Because SIN2V-infected cells accumulated only 40% of the minus strands that were made, cells must possess some process to limit RTC accumulation. The loss of activity by SIN2V RTC after translation was inhibited was stochastic and not due to their inherent instability, based on finding that activity was lost without the degradation of the minus-strand templates. In addition to their normal functions, P23 RTCs exhibited the novel phenotype of being unable to switch from making less to making more genomes than subgenomic 26S mRNA at late times during infections. Our results lend credence to the hypothesis that nsP2 (and possibly nsP3) possesses functions other than those needed solely for RTC activity and that it may also act with the host to regulate minus-strand synthesis and the stability of the RTC

Preparation and Properties of Environmentally Friendly Resin-Based Artificial Stones Fabricated from Ceramic Waste

The rapid development of the traditional ceramic industry contributes considerably to economic advancements; however, the ecological hazards caused by the large amount of sintered ceramic wastes generated during ceramic production and discarded at landfill sites are becoming increasingly severe. To realize the large-scale resource utilization of ceramic waste, sintered ceramic waste was used in this study to partially replace natural quartz sand, and new environmentally friendly artificial stones were fabricated by using vacuum vibration molding and inorganic/organic composite curing technology. The effects of ceramic waste addition and particle size on the mechanical strength, surface hardness, wear resistance, stain resistance, and microstructure of artificial stone materials were investigated. The results showed that the replacement of quartz sand with 40–55% ceramic waste significantly improved the mechanical strength of artificial stone and maintained sufficient surface hardness and wear resistance. When 45% of ceramic waste powder (particle size ≥ 120 mesh) was added, the bending strength of the artificial stone was 64.4 MPa, whereas when 55% of ceramic waste particles with different particle sizes were added, the maximum compressive strength was 158.7 MPa. Good wear resistance and sufficient Moh’s hardness of 5.5–6.5 was obtained for all the samples. The prepared ceramic waste artificial stone also had a dense microstructure and low water absorption and porosity, which are helpful for improving stain resistance

Alirocumab and cardiovascular outcomes after acute coronary syndrome

BACKGROUN

Alirocumab and Cardiovascular Outcomes after Acute Coronary Syndrome

BACKGROUN