Carboxyl terminal domain of Gs alpha specifies coupling of receptors to stimulation of adenylyl cyclase

The alpha subunits of Gs and Gi link different sets of hormone receptors to stimulation and inhibition, respectively, of adenylyl cyclase. A chimeric alpha i/alpha s cDNA was constructed that encodes a polypeptide composed of the amino terminal 60% of an alpha i chain and the carboxyl terminal 40% of alpha s. The cDNA was introduced via a retroviral vector into S49 cyc- cells, which lack endogenous alpha s. Although less than half of the hybrid alpha chain is derived from alpha s, its ability to mediate beta-adrenoceptor stimulation of adenylyl cyclase matched that of the normal alpha s polypeptide expressed from the same retroviral vector in cyc- cells. This result indicates that carboxyl terminal amino acid sequences of alpha s contain the structural features that are required for specificity of interactions with the effector enzyme, adenylyl cyclase, as well as with the hormone receptor.     

Finite-frequency tomography reveals a variety of plumes in the mantle

We present tomographic evidence for the existence of deep-mantle thermal convection plumes. P-wave velocity images show at least six well-resolved plumes that extend into the lowermost mantle: Ascension, Azores, Canary, Easter, Samoa, and Tahiti. Other less well-resolved plumes, including Hawaii, may also reach the lowermost mantle. We also see several plumes that are mostly confined to the upper mantle, suggesting that convection may be partially separated into two depth regimes. All of the observed plumes have diameters of several hundred kilometers, indicating that plumes convey a substantial fraction of the internal heat escaping from Earth.     

Impact of branch reorientation on breaking stress in Liriodendron tulipifera L.

It has been observed that during ice, snow, and wind storms, branches oriented vertically tend to incur more damage than branches oriented horizontally. A study was conducted to determine breaking stress and breaking position of branches reoriented nearly horizontal and nearly vertical. Branches oriented 40–50° from horizontal with mean diameter 4.9 cm (SD ± 0.73) were removed from two trees and transferred to a custom branch pulling station. Branches were reoriented either nearly horizontal (76–89°) or vertical (6–29°) to a reinforced vertical post. Branches were pulled vertically downward from three equidistant positions along the branch until they broke. Failure stress for horizontal oriented branches (64 MPa) was double the stress required to pull vertical oriented branches to failure (32 MPa). Nine of ten horizontal branches failed between the branch base and the pull point closest to the base (proximal pull point); whereas seven of ten vertical branches failed farther from the base, between the proximal and middle pull points. Average length from branch base to failure point for horizontal branches was 12.8 cm, and 74.6 cm for vertical branches. Despite requiring less stress to break, branch angle change at the distal and middle pull points from the original position to the position at failure for vertical branches was greater than for horizontal branches; whereas angle change at the proximal pull point was greater for horizontal branches. Branch taper was not different between reorientation treatments. Implications on pruning strategies are discussed.     

How many herbarium specimens are needed to detect threatened species?

The distribution, ecology and conservation status of the majority of plant species are poorly known. One of the challenges ahead is to address this knowledge gap and give more emphasis to this important group of species that represents a critical component of earth’s biodiversity. Full conservation assessments require expert knowledge of the group concerned, but for the majority of plant species, especially those from the tropics, the best source of knowledge is specimens housed within herbaria. Digitisation projects are underway to render information from this important global biodiversity resource more accessible; the next step is to assemble and utilise these data to make better informed conservation decisions. One crucial question is: how many herbarium specimens are needed to detect threatened species? Such information would inform and help to prioritise digitisation efforts. Using 11,461 herbarium records we assessed species geographic range to determine a preliminary conservation status of 661 endemic species of Leguminosae and Orchidaceae from Madagascar, following the IUCN criteria. By capturing 15 georeferenced specimens per species we produced range estimates for use in conservation assessments consistent with estimates based on all known specimens, for more than 95% of species. None of the threatened species were misclassified as not threatened, and less than 3% of species would receive conservation support as a result of being falsely identified as threatened. This approach can therefore help progress towards the Global Strategy for Plant Conservation target of a conservation assessment for each plant species, while reducing digitisation effort by up to half.     

Design, loading, and water quality in recirculating systems for Atlantic Salmon (Salmo salar) at the USDA ARS National Cold Water Marine Aquaculture Center (Franklin, Maine)

The Northeastern U.S. has the ideal location and unique opportunity to be a leader in cold water marine finfish aquaculture. However, problems and regulations on environmental issues, mandatory stocking of 100% native North American salmon, and disease have impacted economic viability of the U.S. salmon industry. In response to these problems, the USDA ARS developed the National Cold Water Marine Aquaculture Center (NCWMAC) in Franklin, Maine. The NCWMAC is adjacent to the University of Maine Center for Cooperative Aquaculture Research on the shore of Taunton Bay and shares essential infrastructure to maximize efficiency. Facilities are used to conduct research on Atlantic salmon and other cold water marine finfish species. The initial research focus for the Franklin location is to develop a comprehensive Atlantic salmon breeding program from native North American fish stocks leading to the development and release of genetically improved salmon to commercial producers. The Franklin location has unique ground water resources to supply freshwater, brackish water, salt water or filtered seawater to fish culture tanks. Research facilities include office space, primary and secondary hygiene rooms, and research tank bays for culturing 200+ Atlantic salmon families with incubation, parr, smolt, on-grow, and broodstock tanks. Tank sizes are 0.14 m³ for parr, 9 m³ for smolts, and 36, 46 and 90 m³ for subadults and broodfish. Culture tanks are equipped with recirculating systems utilizing biological (fluidized sand) filtration, carbon dioxide stripping, supplemental oxygenation and ozonation, and ultraviolet sterilization. Water from the research facility discharges into a wastewater treatment building and passes through micro-screen drum filtration, an inclined traveling belt screen to exclude all eggs or fish from the discharge, and UV irradiation to disinfect the water. The facility was completed in June 2007, and all water used in the facility has been from groundwater sources. Mean facility discharge has been approximately 0.50 m³/min (130 gpm). The facility was designed for stocking densities of 20–47 kg/m³ and a maximum biomass of 26,000 kg. The maximum system density obtained from June 2007 through January 2008 has approached 40 kg/m³, maximum facility biomass was 11,021 kg, water exchange rates have typically been 2–3% of the recirculating system flow rate, and tank temperatures have ranged from a high of 15.4 °C in July to a low of 6.6 °C in January 2008 without supplemental heating or cooling.     

月季新品种‘糖果雪山’

 ‘糖果雪山’是从现代切花月季品种‘雪山’栽培群体中选育出来的芽变新品种。花色为白 底深粉边,花径10 ~ 13 cm;温室栽培单枝切花生育期为38 ~ 42 d,切枝长度90 ~ 110 cm,年产量280 ~ 300 枝 · m^-2。     

Dermatomycosis caused by Paranannizziopsis australasiensis in five tuatara (Sphenodon punctatus) and a coastal bearded dragon (Pogona barbata) in a zoological collection in New Zealand

CASE HISTORY: Health monitoring of tuatara (Sphenodon punctatus) at Auckland Zoo between 2001 and 2009 showed that 58/93 tuatara had been affected by dermatitis of unknown origin. From 2011 onwards, cases of suspected fungal dermatitis underwent extensive diagnostic investigations.

CLINCAL FINDINGS: Six cases of dermatomycosis were attributed to Paranannizziopsis australasiensis, five in tuatara and one in a coastal bearded dragon (Pogona barbata). Cases presented typically as raised, yellow to brown encrustations on the skin. Severe cases progressed to necrotising ulcerative dermatitis, and in the bearded dragon to fatal systemic mycosis. Following topical and systemic treatments, lesions resolved in all five tuatara.

LABORATORY FINDINGS: Histopathological examination of skin biopsy samples revealed dermatitis with intralesional septate branching hyphae. Fungal culture yielded isolates morphologically resembling Chrysosporium species, and isolates were submitted for molecular confirmation and sequencing of DNA.

DIAGNOSIS: All six cases were confirmed as dermatitis due to infection with P. australasiensis, on the basis of fungal culture and DNA sequencing of isolates.

CLINICAL RELEVANCE: These are the first reported cases of dermatomycosis associated with P. australasiensis infection in tuatara, and the first cases in which systemic therapeutic agents have been used in the treatment of such disease. Tuatara at the Auckland Zoo are now routinely examined every 3 months and tissue samples from any lesions sent for histopathology and fungal culture. Further work to elucidate the epidemiology and significance of P. australasiensis infections in reptiles in New Zealand is important for both welfare and conservation purposes.     

Phenylpyrazoles,a new class of pesticide: Effects on neuromuscular transmission and acetylcholine responses

Phenylpyrazoles constitute a newly developed class of chemicals with insecticidal and herbicidal properties. In acute toxicity experiments in rats, near-lethal doses of phenylpyrazoles produce neurotoxic symptoms with an unknown mode of action. We have investigated the effects of two phenylpyrazoles, SLA4722 and SLA4685, in the frog neuromuscular junction and in the clonal muscle cell line BC3H-1. In the frog neuromuscular junction SLA4722 at concentrations ? 10^?5 M caused a pronounced increase in the frequency of miniature endplate potentials (MEPPs). SLA4685 caused a similar increase but was less potent. In the clonal muscle cell line BC3H-1, SLA4685 produced a concentration-dependent block of the acetylcholine (ACh) response (IC₅₀ = 2.4(±0.3) × 10^?5 M). At 10^?6 M a slight potentiating effect of SLA4685 on the ACh response was observed. SLA4722 was less potent in this preparation. The increased transmitter release might, at least partly, be responsible for the excitatory effects of the phenylpyrazoles in intact animals.