Characteristics of operator entry into Iowa farming, 1959-60

The study of operator entry in Iowa farming reported in this bulletin had two primary objectives: ( 1) to establish a benchmark for analyzing posting, the conditions under which they achieved entry and the financial results experienced during the initial year of operation. A series of follow-up studies of the same group is planned for future years. Data for the current study were obtained by personal interview from a sample of farm operators who entered farming in 1959 and 1960. The sample of entrants was obtained from a state-wide sample survey involving nearly 7,000 farm operators. It was based on a self-weighting single-stage sample of area segments drawn at random from a universe defined as the open-country zone of Iowa by the current Master Sample materials. Entrants were classified into two groups: beginning entrants and other entrants. The beginning-entrant group consisted of persons who had never farmed before the year of entry and persons who had farmed before the year of entry but had disposed of their farming assets with the apparent intent of permanent withdrawal. Other entrants consisted of persons who had farmed during an earlier period but had temporarily withdrawn from farming (retained their farming assets) with the apparent intent of re-entering

Plant-Derived Bioactive Lipids Impacts Glucose Homeostasis and Energy Metabolism in Mice

There is a crucial need to identify and test sustainable alternatives to fish oil as a means to supplement dietary omega (n-3) fatty acids which have demonstrated health benefits to humans with metabolic syndrome and its associated diseases. Echium oil has a high content of the n-3 fatty acid stearidonic acid (SDA), a precursor of the bioactive lipids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) found in fatty cold-water fish, with known or possible functions to improve metabolism and delay the onset of or prevent diabetes. To characterize the effects of dietary Echium oil (EO) vs. fish oil (FO), the oils were formulated into either a low-fat (10% kcal; LF) or high fat (60% kcal; HF) diabetogenic diet and fed to male C57BL/6 Tac mice for 12 weeks. Compared to the low-fat or high-fat controls without the supplementation of EO or FO, EO and FO diets had no effect on blood glucose concentrations or plasma insulin levels throughout the study. The EO-enriched HF diet improved glucose tolerance by week 12 compared to the HF-CON (p\u3c0.05) and HF-FO (p\u3c0.1) groups. EO supplementation reduced visceral fat weight without affecting body mass, promoted a metabolically favorable high polyunsaturated fatty acid (PUFA) to saturated fatty acid (SFA) ratio in adipose and muscle tissues compared to the HF-CON and HF-FO diet groups, and led to higher tissue EPA and DHA concentrations compared to both LF and HF CON (p\u3c0.1). Tissue EPA and DHA in EO were not as high as the concentrations found in mice fed the FO diets for both HF and LF. In conclusion, EO-supplemented diets in mice appear to have distinct effects from FO diets that may be exploited in future strategies to curtail metabolic disorders

Vaccine Protection Against Zika Virus from Brazil

Zika virus (ZIKV) is a flavivirus that is responsible for an unprecedented current epidemic in Brazil and the Americas1,2. ZIKV has been causally associated with fetal microcephaly, intrauterine growth restriction, and other birth defects in both humans3–8 and mice9–11. The rapid development of a safe and effective ZIKV vaccine is a global health priority1,2, but very little is currently known about ZIKV immunology and mechanisms of immune protection. Here we show that a single immunization of a plasmid DNA vaccine or a purified inactivated virus vaccine provides complete protection in susceptible mice against challenge with a ZIKV outbreak strain from northeast Brazil. This ZIKV strain has recently been shown to cross the placenta and to induce fetal microcephaly and other congenital malformations in mice11. We produced DNA vaccines expressing full-length ZIKV pre-membrane and envelope (prM-Env) as well as a series of deletion mutants. The full-length prM-Env DNA vaccine, but not the deletion mutants, afforded complete protection against ZIKV as measured by absence of detectable viremia following challenge, and protective efficacy correlated with Env-specific antibody titers. Adoptive transfer of purified IgG from vaccinated mice conferred passive protection, and CD4 and CD8 T lymphocyte depletion in vaccinated mice did not abrogate protective efficacy. These data demonstrate that protection against ZIKV challenge can be achieved by single-shot subunit and inactivated virus vaccines in mice and that Env-specific antibody titers represent key immunologic correlates of protection. Our findings suggest that the development of a ZIKV vaccine for humans will likely be readily achievable

Characteristics of operator entry into Iowa farming, 1959-60

The study of operator entry in Iowa farming reported in this bulletin had two primary objectives: ( 1) to establish a benchmark for analyzing posting, the conditions under which they achieved entry and the financial results experienced during the initial year of operation. A series of follow-up studies of the same group is planned for future years. Data for the current study were obtained by personal interview from a sample of farm operators who entered farming in 1959 and 1960. The sample of entrants was obtained from a state-wide sample survey involving nearly 7,000 farm operators. It was based on a self-weighting single-stage sample of area segments drawn at random from a universe defined as the open-country zone of Iowa by the current Master Sample materials. Entrants were classified into two groups: beginning entrants and other entrants. The beginning-entrant group consisted of persons who had never farmed before the year of entry and persons who had farmed before the year of entry but had disposed of their farming assets with the apparent intent of permanent withdrawal. Other entrants consisted of persons who had farmed during an earlier period but had temporarily withdrawn from farming (retained their farming assets) with the apparent intent of re-entering.</p

Sesquiterpene Induction by the Balsam Woolly Adelgid (Adelges piceae) in Putatively Resistant Fraser Fir (Abies fraseri)

Fraser fir, Abies fraseri (Pursh) Poir., is a tree endemic to the Southern Appalachians and is found only in a few isolated populations at high elevations. Fraser firs are also cultivated on a commercial scale as Christmas trees. The species is imperiled by an introduced insect, the balsam woolly adelgid, Adelges piceae Ratzeburg (BWA). The insect severely damages Christmas tree crops and has caused substantial Fraser fir mortality in natural stands. Foliar terpenoids are one mechanism of host plant defense against invading insects and may be one focus of future Christmas tree breeding efforts. This study examines the correlation of foliar terpenoids with Fraser fir performance when infested with BWA. GC-MS and GC-FID analysis of artificially infested Fraser fir foliage reveals that increased concentrations of four terpenoid compounds are associated with BWA infestations. Foliar concentrations of two sesquiterpenes, camphene and humulene, are significantly higher in putatively resistant Fraser fir clones than in more susceptible clones after sustained adelgid feeding for a period of 20 weeks. Although it is unclear if the induction of these sesquiterpenes in the host fir is directly contributing to adelgid resistance, these compounds could serve as effective indicators while screening for BWA resistance in future Christmas tree breeding programs