Evaluating Success Factors and Challenges Among Small-Scale Agricultural Producers: A Texas Case Study

Literature on small farms in the U.S. is limited though they are the most numerous farm type, generate over twenty percent of agricultural production, and are more likely to be operated by historically underserved (i.e., beginning, minority, veteran, women, young) farmers than large-scale farms. This article details an online survey study of small-scale agricultural producers using a purposive sample from Texas. We used cross tabulations to evaluate qualitative operational and demographic (e.g., age, gender) factors of success, finding several significant variables with moderate effect sizes. Generally, producers regarded quality of life as more important to success than profitability. Producers’ top challenges were capital, production, marketing, legal, financial, informational, and social, in that order. While results may not be representative of all small producers, in Texas or otherwise, they provide an important look at an understudied population who contribute meaningfully to sustainable production, local and regional food systems, and overall agricultural structure

Assessing the Gene Content of the Megagenome: Sugar Pine (Pinus lambertiana).

Sugar pine (Pinus lambertiana Douglas) is within the subgenus Strobus with an estimated genome size of 31 Gbp. Transcriptomic resources are of particular interest in conifers due to the challenges presented in their megagenomes for gene identification. In this study, we present the first comprehensive survey of the P. lambertiana transcriptome through deep sequencing of a variety of tissue types to generate more than 2.5 billion short reads. Third generation, long reads generated through PacBio Iso-Seq have been included for the first time in conifers to combat the challenges associated with de novo transcriptome assembly. A technology comparison is provided here to contribute to the otherwise scarce comparisons of second and third generation transcriptome sequencing approaches in plant species. In addition, the transcriptome reference was essential for gene model identification and quality assessment in the parallel project responsible for sequencing and assembly of the entire genome. In this study, the transcriptomic data were also used to address questions surrounding lineage-specific Dicer-like proteins in conifers. These proteins play a role in the control of transposable element proliferation and the related genome expansion in conifers

Descriptive Complexity of Deterministic Polylogarithmic Time and Space

We propose logical characterizations of problems solvable in deterministic polylogarithmic time (PolylogTime) and polylogarithmic space (PolylogSpace). We introduce a novel two-sorted logic that separates the elements of the input domain from the bit positions needed to address these elements. We prove that the inflationary and partial fixed point vartiants of this logic capture PolylogTime and PolylogSpace, respectively. In the course of proving that our logic indeed captures PolylogTime on finite ordered structures, we introduce a variant of random-access Turing machines that can access the relations and functions of a structure directly. We investigate whether an explicit predicate for the ordering of the domain is needed in our PolylogTime logic. Finally, we present the open problem of finding an exact characterization of order-invariant queries in PolylogTime.Comment: Submitted to the Journal of Computer and System Science

Plasmas and Controlled Nuclear Fusion

Contains reports on three research projects.U. S. Atomic Energy Commission (Contract AT(30-1)-3980

Climate response to the 8.2 ka event in coastal California

A fast-growing stalagmite from the central California coast provides a high-resolution record of climatic changes synchronous with global perturbations resulting from the catastrophic drainage of proglacial Lake Agassiz at ca. 8.2 ka. High frequency, large amplitude variations in carbon isotopes during the 8.2 ka event, coupled with pulsed increases in phosphorus concentrations, indicate more frequent or intense winter storms on the California coast. Decreased magnesium-calcium ratios point toward a sustained increase in effective moisture during the event, however the magnitude of change in Mg/Ca suggests this event was not as pronounced on the western North American coast as anomalies seen in the high northern latitudes and monsoon-influenced areas. Nevertheless, shifts in the White Moon Cave record that are synchronous within age uncertainties with cooling of Greenland, and changes in global monsoon systems, suggest rapid changes in atmospheric circulation occurred in response to freshwater input and associated cooling in the North Atlantic region. Our record is consistent with intensification of the Pacific winter storm track in response to North Atlantic freshwater forcing, a mechanism suggested by simulations of the last deglaciation, and indicates this intensification led to increases in precipitation and infiltration along the California coast during the Holocene

A Study of the Diverse T Dwarf Population Revealed by WISE

We report the discovery of 87 new T dwarfs uncovered with the Wide-field Infrared Survey Explorer (WISE) and 3 brown dwarfs with extremely red near-infrared colors that exhibit characteristics of both L and T dwarfs. Two of the new T dwarfs are likely binaries with L7 ± 1 primaries and mid-type T secondaries. In addition, our follow-up program has confirmed 10 previously identified T dwarfs and 4 photometrically selected L and T dwarf candidates in the literature. This sample, along with the previous WISE discoveries, triples the number of known brown dwarfs with spectral types later than T5. Using the WISE All-Sky Source Catalog we present updated color-color and color-type diagrams for all the WISE-discovered T and Y dwarfs. Near-infrared spectra of the new discoveries are presented along with spectral classifications. To accommodate later T dwarfs we have modified the integrated flux method of determining spectral indices to instead use the median flux. Furthermore, a newly defined J-narrow index differentiates the early-type Y dwarfs from late-type T dwarfs based on the J-band continuum slope. The K/J indices for this expanded sample show that 32% of late-type T dwarfs have suppressed K-band flux and are blue relative to the spectral standards, while only 11% are redder than the standards. Comparison of the Y/J and K/J index to models suggests diverse atmospheric conditions and supports the possible re-emergence of clouds after the L/T transition. We also discuss peculiar brown dwarfs and candidates that were found not to be substellar, including two young stellar objects and two active galactic nuclei. The substantial increase in the number of known late-type T dwarfs provides a population that will be used to test models of cold atmospheres and star formation. The coolest WISE-discovered brown dwarfs are the closest of their type and will remain the only sample of their kind for many years to come

Herbal extracts and memory enhancement: response to Scholey et al.

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/46364/1/213_2004_Article_2063.pd

Evidence for Direct Roles of Two Additional Factors, SECp43 and Soluble Liver Antigen, in the Selenoprotein Synthesis Machinery

Selenocysteine (Sec) is inserted into selenoproteins co-translationally with the help of various cis- and trans-acting factors. The specific mechanisms of Sec biosynthesis and insertion into protein in eukaryotic cells, however, are not known. Two proteins, SECp43 and the soluble liver antigen (SLA), were previously reported to interact with tRNA [Ser]Sec, but their functions remained elusive. Herein, we report that knockdown of SECp43 in NIH3T3 or TCMK-1 cells using RNA interference technology resulted in a reduction in the level of methylation at the 2’-hydroxylribosyl moiety in the wobble position (Um34) of Sec tRNA [Ser]Sec, and consequently reduced glutathione peroxidase 1 expression. Double knockdown of SECp43 and SLA resulted in decreased selenoprotein expression. SECp43 formed a complex with Sec tRNA [Ser]Sec and SLA, and the targeted removal of one of these proteins affected the binding of the other to Sec tRNA [Ser]Sec. SECp43 was located primarily in the nucleus, whereas SLA was found in the cytoplasm. Co-transfection of both proteins resulted in the nuclear translocation of SLA suggesting that SECp43 may also promote shuttling of SLA and Sec tRNA [Ser]Sec between different cellular compartments. Taken together, these data establish the role of SECp43 and SLA in selenoprotein biosynthesis through interaction with tRNA [Ser]Sec in a multiprotein complex. The data also reveal a role of SECp43 in regulation of selenoprotein expression by affecting the synthesis of Um34 on tRNA[ [Ser]Sec and the intracellular location of SLA

A first-in-human phase 1 study of cavrotolimod, a TLR9 agonist spherical nucleic acid, in healthy participants: Evidence of immune activation

IntroductionTumor immunotherapy is designed to control malignancies through the host immune response but requires circumventing tumor-dysregulated immunomodulation through immunostimulation, relieving immunorepression, or a combination of both approaches. Here we designed and characterized cavrotolimod (formerly AST-008), an immunostimulatory spherical nucleic acid (SNA) compound targeting Toll-like receptor 9 (TLR9). We assessed the safety and pharmacodynamic (PD) properties of cavrotolimod in healthy participants in a first-in-human Phase 1 study under protocol AST-008-101 (NCT03086278; https://clinicaltrials.gov/ct2/show/NCT03086278).MethodsHealthy participants aged 18 to 40 years were enrolled to evaluate four dose levels of cavrotolimod across four cohorts. Each cohort included four participants, and all received a single subcutaneous dose of cavrotolimod. The dose levels were 5, 10, 12.5 and 18.8 µg/kg.Results and discussionCavrotolimod was well tolerated and elicited no serious adverse events or dose limiting toxicities at the doses tested. The results demonstrated that cavrotolimod is a potent innate immune activator, specifically stimulating Th1-type immune responses, and exhibits PD properties that may result in anti-tumor effects in patients with cancer. This study suggests that cavrotolimod is a promising clinical immunotherapy agent