A longevity-specific bank of induced pluripotent stem cells from centenarians and their offspring.

Centenarians provide a unique lens through which to study longevity, healthy aging, and resiliency. Moreover, models of human aging and resilience to disease that allow for the testing of potential interventions are virtually non-existent. We obtained and characterized over 50 centenarian and offspring peripheral blood samples including those connected to functional independence data highlighting resistance to disability and cognitive impairment. Targeted methylation arrays were used in molecular aging clocks to compare and contrast differences between biological and chronological age in these specialized subjects. Isolated peripheral blood mononuclear cells (PBMCs) were then successfully reprogrammed into high-quality induced pluripotent stem cell (iPSC) lines which were functionally characterized for pluripotency, genomic stability, and the ability to undergo directed differentiation. The result of this work is a one-of-a-kind resource for studies of human longevity and resilience that can fuel the discovery and validation of novel therapeutics for aging-related disease.

Arabidopsis CDF3 transcription factor increases carbon and nitrogen assimilation and yield in trans-grafted tomato plants.

Grafting in tomato (Solanum lycopersicum L.) has mainly been used to prevent damage by soil-borne pathogens and the negative effects of abiotic stresses, although productivity and fruit quality can also be enhanced using high vigor rootstocks. In the context of a low nutrients input agriculture, the grafting of elite cultivars onto rootstocks displaying higher Nitrogen Use Efficiency (NUE) supports a direct strategy for yield maximization. In this study we assessed the use of plants overexpressing the Arabidopsis (AtCDF3) or tomato (SlCDF3) CDF3 genes, previously reported to increase NUE in tomato, as rootstocks to improve yield in the grafted scion under low N inputs. We found that the AtCDF3 gene induced greater production of sugars and amino acids, which allowed for greater biomass and fruit yield under both sufficient and limiting N supplies. Conversely, no positive impact was found with the SlCDF3 gene. Hormone analyses suggest that gibberellins (GA4), auxin and cytokinins (tZ) might be involved in the AtCDF3 responses to N. The differential responses triggered by the two genes could be related, at least in part, to the mobility of the AtCDF3 transcript through the phloem to the shoot. Consistently, a higher expression of the target genes of the transcription factor, such as glutamine synthase 2 (SlGS2) and GA oxidase 3 (SlGA3ox), involved in amino acid and gibberellin biosynthesis, respectively, was observed in the leaves of this graft combination. Altogether, our results provided further insights into the mode of action of CDF3 genes and their biotechnology potential for transgrafting approaches.

An evaluation of the Paycheck Protection Program using administrative payroll microdata.

The Paycheck Protection Program (PPP), a principal element of the fiscal stimulus enacted by Congress in response to the COVID-19 economic shock, was intended to assist small businesses to maintain employment and wages during the crisis, as well as cover other expenses. We use high-frequency administrative payroll data from ADP-one of the world's largest payroll processing firms-to estimate the causal effect of the PPP on the evolution of employment at PPP-eligible firms relative to PPP-ineligible firms, where eligibility is determined by industry-specific firm-size cutoffs. Our estimates indicate that the PPP boosted employment at eligible firms by between 2 percent to 5 percent at its peak effect around mid-May 2020. The boost to employment waned thereafter and ranged from no effect to a 3 percent boost at the end of 2020. Our estimates imply that employers retained an additional 3.6 million jobs as of mid-May 2020, and 1.4 million jobs at the end of 2020, as a consequence of PPP. The estimated cost per year of employment retained was $ 169 , 000 to $ 258 , 000 , equal to 3.4 to 5.2 times median earnings.