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The main goal of the Marine Light-Mixed Layers program (MLML) was to understand the biological and physical processes controlling bioluminescence in the sub-polar waters of the North Atlantic. Advection is hypothesized to cause much of the low-frequency variability in phyotplankton concentrations at the MLML site. The relationship between phytoplankton distributions and water mass properties was studied in particular.

Data indicate the unreliability of information from the spread for industrial production growth in predicting economic activity contrary to what Benjamin M. Friedman and Kenneth N. Kuttner postulated in a series of articles since 1989. Two outliers in the data indicate the predictive content of the spread, namely, the 1974 Franklin National Bank episode and the imposition of the Carter Credit controls in 1980.

Both abiotic and biotic factors can influence distributions of invasive plant species, and it is important to understand how such factors contribute to invasion success in order to develop successful management strategies. Microstegium vimineum, known as stiltgrass, is an invasive annual grass in U.S. eastern deciduous forests that can outcompete native understory species, decrease diversity, and prevent the regeneration of native trees. Microstegium is also known to form associations with arbuscular mycorrhizal fungi (AMF), but research has yet to demonstrate whether this association has a role in Microstegium invasion and dominance over native vegetation. We conducted a field survey in invaded and uninvaded habitats across six sites near Louisville, KY, USA, to explore the relative importance of biotic versus abiotic factors in predicting Microstegium abundance and size. Canopy openness was the strongest predictor of Microstegium abundance, followed by soil moisture. Soil nitrogen was the strongest predictor of Microstegium tiller height. Surprisingly, AMF extraradical hyphal abundance and root colonization were not significant predictors of Microstegium abundance or size. In terms of abiotic factors, our results confirm previous studies that have demonstrated that Microstegium grows best in areas with high light and high soil moisture; however, our analysis provides further insight by assessing the relative importance of each of these factors for Microstegium invasion. [ABSTRACT FROM AUTHOR]

Inflationary effects experienced during the 1980s are compared to post-World War II US inflation data. Research results indicate that inflation is less persistent in 1981 and that there is a change in the relationship between interest rates and inflation. Inflation in the 1980s is less persistent and cannot be used to predict future inflation trends. Inflation data for the 1980s is comparable to the behavior of inflation during the US gold standard.

Price stability could reduce uncertainty and the detrimental effects on long-term contracts and the allocation of resources. Monetary policymakers are also given less freedom in setting policies. Some of the conditions for price stability such as the targetting of monetary aggregates, nominal GNP, prices and interest rates are examined. It was shown that price stability does not hinder monetary policymakers to aim for short-term stabilization goals.

This paper assesses the real-time performance of the Commerce Department's composite index of leading indicators. The authors find that the composite leading index has failed to provide reliable advance warning of cyclical turning points. One reason for this failure is that the leading index's transition from expansion to contraction generally is not very sharp. Consequently, discerning real-time cyclical peaks in the index is difficult. Transitions from contraction to expansion on average are sharp. However, cyclical troughs in the leading index often precede cyclical troughs in the economy by only a few months. Thus, even timely recognition of troughs in the leading index fails to provide advance warning of turnarounds in the general level of economic activity., I. INTRODUCTION Among all the indexes designed to give advance warning of business-cycle turning points, the Commerce Department's composite index of leading economic indicators (CLI) is the most widely publicized.(1) [...]

A cross-sectional survey research design measured factors related to cigarette use among 2,212 senior high school students. Results showed 14.3% of the sample smoked cigarettes at least occasionally, with 5.3% reporting they were daily smokers. About 12.8% indicated they were ex-smokers. Males and females smoked at almost equal rates, and the percentage of 10th grade student smokers was slightly higher 16.4%) than the percentage of juniors and seniors who smoked. Approximately 22% of Hispanic students, 15% of Caucasian students, and 4.5% of African-American students reported smoking cigarettes at least occasionally. An initial regression analysis used 21 variables to predict cigarette smoking. A more parsimonious regression model ([R.sub.2] = .28), using variables from the initial regression analysis with significance levels of . 01 or less, indicated the most important predictors of cigarette use were ethnic group, attitude to ward females who smoke, close friends' use of cigarettes, personal use of marijuana, best friend's use of cigarettes, personal use of alcohol, and school self-esteem. Implications for school health programs are addressed. (J Sch Health. 1992;62(4):146-150), Research confirms smoking as the most important preventable cause of morbidity and mortality in the U.S.[1] Cigarette smoking is linked to a number of diseases, most notably coronary heart disease [...]

Abstract Background The Natural History Museum (NHM) is developing a repository for schistosomiasis-related material, the Schistosomiasis Collection at NHM (SCAN) as part of its existing Wolfson Wellcome Biomedical Laboratory (WWBL). This is timely because a major research and evaluation effort to understand control and move towards elimination of schistosomiasis in Africa has been initiated by the Schistosomiasis Consortium for Operational Research and Evaluation (SCORE), resulting in the collection of many important biological samples, including larval schistosomes and snails. SCAN will collaborate with a number of research groups and control teams and the repository will acquire samples relevant to both immediate and future research interest. The samples collected through ongoing research and field activities, WWBL’s existing collections, and other acquisitions will be maintained over the long term and made available to the global research community for approved research purposes. Goals include: · Consolidation of the existing NHM schistosome and snail collections and transfer of specimens into suitable long-term storage systems for DNA retrieval, · Long-term and stable storage of specimens collected as part of on going field programmes initially in Africa especially relating to the SCORE research programmes, · Provision of access to snail and schistosome collections for approved research activities.

Abstract Background Motile cilia are essential to the survival and reproduction of many eukaryotes; they are responsible for powering swimming of protists and small multicellular organisms and drive fluids across respiratory and reproductive surfaces in mammals. Although tremendous progress has been made to comprehend the biochemical basis of these complex evolutionarily-conserved organelles, few protein kinases have been reported to co-ordinate ciliary beat. Here we present evidence for p38 mitogen-activated protein kinase (p38 MAPK) playing a role in the ciliary beat of a multicellular eukaryote, the free-living miracidium stage of the platyhelminth parasite Schistosoma mansoni. Results Fluorescence confocal microscopy revealed that non-motile miracidia trapped within eggs prior to hatching displayed phosphorylated (activated) p38 MAPK associated with their ciliated surface. In contrast, freshly-hatched, rapidly swimming, miracidia lacked phosphorylated p38 MAPK. Western blotting and immunocytochemistry demonstrated that treatment of miracidia with the p38 MAPK activator anisomycin resulted in a rapid, sustained, activation of p38 MAPK, which was primarily localized to the cilia associated with the ciliated epidermal plates, and the tegument. Freshly-hatched miracidia possessed swim velocities between 2.17 - 2.38 mm/s. Strikingly, anisomycin-mediated p38 MAPK activation rapidly attenuated swimming, reducing swim velocities by 55% after 15 min and 99% after 60 min. In contrast, SB 203580, a p38 MAPK inhibitor, increased swim velocity by up to 15% over this duration. Finally, by inhibiting swimming, p38 MAPK activation resulted in early release of ciliated epidermal plates from the miracidium thus accelerating development to the post-miracidium larval stage. Conclusions This study supports a role for p38 MAPK in the regulation of ciliary-beat. Given the evolutionary conservation of signalling processes and cilia structure, we hypothesize that p38 MAPK may regulate ciliary beat and beat-frequency in a variety of eukaryotes.

Uterine contractile dysfunction leads to pregnancy complications such as preterm birth and labor dystocia. In humans, it is hypothesized that progesterone receptor isoform PGR-B promotes a relaxed state of the myometrium, and PGR-A facilitates uterine contraction. This hypothesis was tested in vivo using transgenic mouse models that overexpress PGR-A or PGR-B in smooth muscle cells. Elevated PGR-B abundance results in a marked increase in gestational length compared to control mice (21.1 versus 19.1 d respectively, P < 0.05). In both ex vivo and in vivo experiments, PGR-B overexpression leads to prolonged labor, a significant decrease in uterine contractility, and a high incidence of labor dystocia. Conversely, PGR-A overexpression leads to an increase in uterine contractility without a change in gestational length. Uterine RNA sequencing at midpregnancy identified 1,174 isoform-specific downstream targets and 424 genes that are commonly regulated by both PGR isoforms. Gene signature analyses further reveal PGR-B for muscle relaxation and PGR-A being proinflammatory. Elevated PGR-B abundance reduces Oxtr and Trpc3 and increases Plcl2 expression, which manifests a genetic profile of compromised oxytocin signaling. Functionally, both endogenous PLCL2 and its paralog PLCL1 can attenuate uterine muscle cell contraction in a CRISPRa-based assay system. These findings provide in vivo support that PGR isoform levels determine distinct transcriptomic landscapes and pathways in myometrial function and labor, which may help further the understanding of abnormal uterine function in the clinical setting. [ABSTRACT FROM AUTHOR]