Shared selection and genetic architecture drive strikingly repeatable evolution in long-term experimental hybrid populations.

The degree to which evolution repeats itself has implications regarding the major forces driving evolution and the potential for evolutionary biology to be a predictive (versus solely historical) science. To understand the factors that control evolutionary repeatability, we experimentally evolved four replicate hybrid populations of sunflowers at natural sites for up to 14 years and tracked ancestry across the genome. We found that there was very strong negative selection against introgressed ancestry in several chromosomes, but positive selection for introgressed ancestry in one chromosome.

Population genomics reveals strong impacts of genetic drift without purging and guides conservation of bull and giant kelp.

Kelp forests are declining in many parts of the northeast Pacific. In small populations, genetic drift can reduce adaptive variation and increase fixation of recessive deleterious alleles, but natural selection may purge harmful variants. To understand evolutionary dynamics and inform restoration strategies, we investigated genetic structure and the outcomes of genetic drift and purging by sequencing the genomes of 429 bull kelp (Nereocystis luetkeana) and 211 giant kelp (Macrocystis sp.

Transcriptome analysis of novel B16 melanoma metastatic variants generated by serial intracarotid artery injection.

The incidence of brain metastases (BrM) in patients with metastatic melanoma is reported to be 30-50% and constitutes the third most frequent BrM after breast and renal cancers. Treatment strategies including surgical resection, stereotactic radiation, and immunotherapy have improved clinical response rates and overall survival, but the changes that occur in circulating melanoma cells to promote invasion of the brain are not fully understood. To investigate brain tropism, we generated new variants of the B16 mouse melanoma model by serially passaging B16 cells through the brain of immune competent syngeneic C57BL/6 mice.

Enhanced copper passivation in pig manure composting through iron nanoparticle amendment.

As the world's leading producer of pigs, China is now experiencing large-scale pollution derived from agricultural usage of untreated pig manure, where passivation of metal toxicity in pig manure is a major challenge. Here, the effect of green synthesized iron nanoparticle (G-nFe) addition on copper (Cu) transformations during thermophilic aerobic composting of pig manure was investigated. The results revealed that following addition of G-nFe passivation of active Cu forms, including exchangeable (EXC-Cu), carbonate-bound (CARCu), and iron and manganese oxide-bound (IMOCu) Cu increased by 66.