Intense sub-kilometer-scale boundary layer rolls observed in hurricane fran

High-resolution observations obtained with the Doppler On Wheels (DOW) mobile weather radar near the point of landfall of hurricane Fran (1996) revealed the existence of intense, sub-kilometer-scale, boundary layer rolls that strongly modulated the near-surface wind speed. It is proposed that these structures are one cause of geographically varying surface damage patterns that have been observed after some landfalling hurricanes and that they cause much of the observed gustiness, bringing high-velocity air from aloft to the lowest observable levels. High-resolution DOW radar observations are contrasted with lower-resolution observations obtained with an operational weather radar, which underestimated peak low-level wind speeds.     

Amoeboid organisms attacking larvae of the potato root eelworm (Heterodera rostochiensis Woll.) in England and the beet eelworm (H. Schachtii Schm.). in Canada

Samenvatting Amoebe-achtige organismen werden geïsoleerd uit grondmonsters, die cysten vanHeterodera rostochiensis bevatten en afkomstig waren van twee plaatsen in Feltwell Fen, Norfolk, Engeland en uit grond van een perceel in het Blackwell district, Essex County., Ontario, Canada, dat besmet was metH. schachtii. Deze organismen gelijken sterk opTheratromyxa weberi Zwillenberg, die bekend is als parasiet van het aardappelcysteaaltje in Nederland. Er werden enkele verschillen in gedrag tussen de in Engeland en Canada gevonden organismen enT. weberi waargenomen, maar deze kunnen het gevolg zijn van verschillen in kweekwijze.     

A parathyroid hormone-related protein implicated in malignant hypercalcemia: cloning and expression

Humoral hypercalcemia of malignancy is a common complication of lung and certain other cancers. The hypercalcemia results from the actions of tumor factors on bone and kidney. We report here the isolation of full-length complementary DNA clones of a putative hypercalcemia factor, and the expression from the cloned DNA of the active protein in mammalian cells. The clones encode a prepro peptide of 36 amino acids and a mature protein of 141 amino acids that has significant homology with parathyroid hormone in the amino-terminal region. This previously unrecognized hormone may be important in normal as well as abnormal calcium metabolism.     

Blue-light-activated histidine kinases: two-component sensors in bacteria

Histidine kinases, used for environmental sensing by bacterial two-component systems, are involved in regulation of bacterial gene expression, chemotaxis, phototaxis, and virulence. Flavin-containing domains function as light-sensory modules in plant and algal phototropins and in fungal blue-light receptors. We have discovered that the prokaryotes Brucella melitensis, Brucella abortus, Erythrobacter litoralis, and Pseudomonas syringae contain light-activated histidine kinases that bind a flavin chromophore and undergo photochemistry indicative of cysteinyl-flavin adduct formation. Infection of macrophages by B. abortus was stimulated by light in the wild type but was limited in photochemically inactive and null mutants, indicating that the flavin-containing histidine kinase functions as a photoreceptor regulating B. abortus virulence.     

An M2 muscarinic receptor subtype coupled to both adenylyl cyclase and phosphoinositide turnover

To investigate whether a particular receptor subtype can be coupled to multiple effector systems, recombinant M2 muscarinic receptors were expressed in cells lacking endogenous receptor. The muscarinic agonist carbachol both inhibited adenylyl cyclase and stimulated phosphoinositide hydrolysis. The stimulation of phosphoinositide hydrolysis was significantly less efficient and more dependent on receptor levels than the inhibition of adenylyl cyclase. Both responses were mediated by guanine nucleotide binding proteins, as evidenced by their inhibition by pertussis toxin; the more efficiently coupled adenylyl cyclase response was significantly more sensitive. Thus, individual subtypes of a given receptor are capable of regulating multiple effector pathways.