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InDrosophila melanogasterthere are two genes encoding ribosomal protein S5,RpS5aandRpS5b.Here, we demonstrate thatRpS5bis required for oogenesis. Females lackingRpS5bproduce ovaries with numerous developmental defects that undergo widespread apoptosis in mid-oogenesis. Females lacking germlineRpS5aare fully fertile, but germline expression of interfering RNA targeting germlineRpS5ain anRpS5bmutant background worsened theRpS5bphenotype and blocked oogenesis before egg chambers form. A broad spectrum of mRNAs co-purified in immunoprecipitations with RpS5a, while RpS5b-associated mRNAs were specifically enriched for GO terms related to mitochondrial electron transport and cellular metabolic processes. Consistent with this,RpS5bmitochondrial fractions are depleted for proteins linked to oxidative phosphorylation and mitochondrial respiration, andRpS5bmitochondria tended to form large clusters and had more heterogeneous morphology than those from controls. We conclude that RpS5b-containing ribosomes preferentially associate with particular mRNAs and serve an essential function in oogenesis.

Background Fruit growers largely depend on chemical control to reduce populations of the economically damaging invasive fly, Drosophila suzukii (Matsumura). Drosophila suzukii is susceptible to high temperatures and low humidity; therefore, it may be possible to implement cultural control practices that create microclimates unfavorable for its development and survival. In addition to other fruit production benefits, in-row mulches may impede the development of D. suzukii immatures when larvae leave the fruit to pupate in the soil. This study compared the effects of different mulches (black polypropylene fabric weedmats, sawdust, and wood chips) on temperature and relative humidity (RH), and on adult emergence of D. suzukii from larvae in blueberries and pupae, both above and below the ground surface in blueberry plantings (Vaccinium corymbosum L.). Results Across regions, both lower larval survival and longer periods with high suboptimal temperatures occurred above the ground in comparison to buried below the ground, regardless of mulch type. Fewer D. suzukii adults emerged from larvae on weedmat mulch at one site, but there was no effect of mulch type on temperature, RH, or D. suzukii emergence at most sites. The relationships between temperature, RH, and the emergence of adults from larvae and pupae varied by region. Natural infestation by D. suzukii in blueberries was lower over weedmat compared to wood-based mulches at one site. Greenhouse experiments showed that larvae burrowed to pupate underneath sawdust mulch, but were unable to pupate underneath a weedmat mulch. Conclusions Although weedmats may not modify temperatures or RH enough to consistently affect D. suzukii emergence, they can reduce field suitability for D. suzukii by providing a barrier that prevents larvae from reaching favorable pupation microhabitats underground. © 2019 Society of Chemical Industry.

Insect activity, survival, and development are affected by climatic conditions that elicit effects at multiple scales. Pruning small fruit crop canopies alters the microclimate, which in turn may influence insect pest activity. We investigated the effect of three canopy density treatments (high, medium, low) on Drosophila suzukii (Matsumura) (Diptera: Drosophilidae) fruit infestation in blueberries and caneberries using a two-year, multi-state experiment. We quantified the effect of canopy density on canopy microclimate, fruit quality (total soluble solids, fruit firmness), and yield. To better understand heterogeneity in canopy microclimate, parameters were further separated by canopy location (exterior vs. interior) in Maryland. In both crops, meta-analyses reveal small magnitude effects of the plant canopy on microclimate, whereas analysis of variance did not separate these effects, with mean canopy differences of 0.1–0.7 °C and 0.5–1.3 % relative humidity (RH) between caneberry canopy densities and locations. In caneberry multi-state trials, 0.14 fewer D. suzukii larvae (g fruit)−1 occurred on average in the low canopy density treatment, and 0.2 fewer D. suzukii larvae (g fruit)−1 occurred in exterior raspberries in Maryland compared with the canopy interior. Artificially infested blueberry fruit indicated immature D. suzukii survival within fruit can vary across canopy densities and locations. Although lower total yield was produced in low density canopies, canopy density did not influence berry quality or marketable yield. Microhabitats provide important shelter from extreme environmental conditions; the availability of shelter and ability to locate it affects insect pest populations and distributions. Understanding how crop canopy microclimate affects D. suzukii infestation can inform efforts to develop habitat manipulation tactics and improve the efficiency of fruit production.

The Internet is becoming an increasingly important component of political campaigns. This study employed content analysis to apply Functional Theory and Issue Ownership Theory to Obama’s and McCain’s presidential candidate webpages in the 2008 campaign. Acclaims (92%) were more common than attacks (98%); defenses did not occur in this sample. Policy (82%) was addressed more than character (18%). When discussing policy, these candidates addressed future plans most frequently, followed by general goals and then past deeds; on character, candidates discussed ideals, then personal qualities, and then leadership ability. This study shows that as candidates use the Internet to reach voters, their webpages conform to theoretical expectations.

To determine whether in vitro secretion of two vasoactive peptides, endothelin and parathyroid hormone-related peptide (PTHrP), is different in decidua from pregnancies complicated by intrauterine growth restriction (IUGR) than in normal pregnancies.In ten IUGR and nine gestational age-matched control pregnancies, decidua was collected at delivery and explants cultured for 24 hours. Endothelin and PTHrP concentrations in the conditioned medium were determined. Lactate dehydrogenase release into the medium was measured at 4 and 24 hours in a separate group of four IUGR and three control decidua.Endothelin and PTHrP secretion by the decidua of the IUGR pregnancies were markedly lower than those in controls (endothelin 51 +/- 11 versus 105 +/- 16 pg/100 mg tissue/24 hours, P = .01; PTHrP 164 +/- 17 versus 641 +/- 209 ng/100 mg tissue/24 hours, P = .02). Lactate dehydrogenase release into the medium was not different between the IUGR and control decidua.Based on the known effects of endothelin and PTHrP on vascular smooth muscle, it was originally anticipated that more endothelin and less PTHrP would be secreted by the IUGR decidua than the control. The finding that both peptides decreased could not be explained by route of delivery or global tissue dysfunction. Investigation of potential mediators of decidual ET and PTHrP will be necessary to determine why these hormones are both decreased in pregnancies complicated by IUGR.

A study of the radial increment growth of native eastern white pine (Pinusstrobus L.) evaluated the possible effects of oxidant air pollution (primarily ozone) in long-term growth of forest species in the Blue Ridge Mountains of Virginia. Ten plots of three white pines of reproducing age (one each classified as tolerant, intermediate, and sensitive to ozone on a foliar basis) were sampled. Plots were dispersed over 446 km from the northern end of the Skyline Drive in Shenandoah National Park to the southern most part of the Blue Ridge Parkway in Virginia. Mean annual radial increment growth of the ozone sensitive trees was significantly smaller (P = 0.01) than that of tolerant trees for the period 1955–1978. Mean increment growth of all trees, regardless of their sensitivity to ozone, decreased during the period. Precipitation was positively correlated with radial growth in all sensitivity classes prior to 1964, but negatively correlated after 1964.

Along the Blue Ridge Parkway in Virginia, branchlets and pollen were collected from native eastern white pine (Pinusstrobus L.) trees that were sensitive, intermediate, and tolerant to oxidant air pollution based on foliar symptom expression. Fumigation of branchlets with 0.10 ppm ozone (O3) for 4 or 8 h/day until anthesis did not affect pollen production or germinability. However, the percent germination was significantly (P ≤ 0.01) reduced in pollen exposed under wet conditions to 0.15 O3 for 4 h. The importance of this finding in the reproduction of pines is discussed.

A cDNA probe (HOAT1) for ornithine aminotransferase (OAT) has recently been used to map (1) the structural gene for this enzyme to chromosome 10 and (2) several related DNA sequences to the X chromosome. We have defined six RFLPs for OAT, to explore its possible role in gyrate atrophy (GA) of the choroid and retina, an autosomal recessive genetic disorder associated with a deficiency of OAT activity. The RFLPs, which are detected by noncoding single-copy probes from the OAT gene and by subclones of the HOAT1 cDNA, all map on human chromosome 10, producing an overall level of heterozygosity for the OAT locus of 83%. Using the RFLPs, we have determined that the OAT locus segregates concordantly with GA in one available pedigree. Furthermore, the RFLPs display significant disequilibrium with GA, providing genetic evidence implicating a defect in the OAT structural gene as the cause of this disorder. The RFLPs for OAT are potentially applicable to prenatal diagnosis and carrier detection in families with a previous history of GA. They will also allow identification of specific haplotypes associated with GA chromosomes, as a guide for more detailed molecular-genetic investigations of the mutations underlying the disorder.

A new Ford speed control amplifier has been designed using an I 2L custom integrated circuit (IC) which was independently designed by multiple vendors from functional block diagrams, which included definition of all external components and characterization of all inputs and outputs. The IC's contain both analog and digital functions on a single substate. The designs have resulted in a speed control amplifier providing more features, reduced package size, and lower warranty return projections than the previous design.

(1959). The Occurrence of the Acarine Mite Acarapis Woodi in the Honeybee in the Belgian Congo. Bee World: Vol. 40, No. 6, pp. 156-156.