Evergreen coniferous forests of the pacific northwest

The massive, evergreen coniferous forests in the Pacific Northwest are unique among temperate forest regions of the world. The region's forests escaped decimation during Pleistocene glaciation; they are now dominated by a few broadly distributed and well-adapted conifers that grow to large size and great age. Large trees with evergreen needle- or scale-like leaves have distinct advantages under the current climatic regime. Photosynthesis and nutrient uptake and storage are possible during the relatively warm, wet fall and winter months. High evaporative demand during the warm, dry summer reduces photosynthesis. Deciduous hardwoods are repeatedly at a disadvantage in competing with conifers in the regional climate. Their photosynthesis is predominantly limited to the growing season when evaporative demand is high and water is often limiting. Most nutrients needed are also less available at this time. The large size attained by conifers provides a buffer against environmental stress (especially for nutrients and moisture). The long duration between destructive fires and storms permits conifers to outgrow hardwoods with more limited stature and life spans.     

Redwood/tanoak stand development and response to tanoak mortality caused by Phytophthora ramorum

Coast redwood (Sequoia sempervirens) and tanoak (Lithocarpus densiflorus) form mixed-evergreen forests along the northern California coast. In the mid-1990s, an introduced pathogen (Phytophthora ramorum) began causing extensive mortality of tanoak in these forests. This research reconstructed stand development patterns occurring in stands with and without the pathogen, measured stand responses to tanoak mortality, and developed projections of future stand development and structure in the presence of P. ramorum. Redwood forms an upper canopy layer while tanoak forms a multicohort lower canopy, resulting in distinct vertical stratification patterns. Individual redwood tree response patterns to tanoak mortality included crown expansion, increased basal sprouting, and increased basal area growth. Future stand structures will likely have greater proportions of redwood relative to tanoak.     

Allometric relationships predicting foliar biomass and leaf area:sapwood area ratio from tree height in five Costa Rican rain forest species

We developed allometric equations to predict whole-tree leaf area (A(l)), leaf biomass (M(l)) and leaf area to sapwood area ratio (A(l):A(s)) in five rain forest tree species of Costa Rica: Pentaclethra macroloba (Willd.) Kuntze (Fabaceae/Mim), Carapa guianensis Aubl. (Meliaceae), Vochysia ferru-gi-nea Mart. (Vochysiaceae), Virola koshnii Warb. (Myris-ticaceae) and Tetragastris pana-mensis (Engl.) Kuntze (Burseraceae). By destructive analyses (n = 11-14 trees per species), we observed strong nonlinear allometric relationships (r(2) >/= 0.9) for predicting A(l) or M(l) from stem diameters or A(s) measured at breast height. Linear relationships were less accurate. In general, A(l):A(s) at breast height increased linearly with tree height except for Penta-clethra, which showed a negative trend. All species, however, showed increased total A(l) with height. The observation that four of the five species increased in A(l):A(s) with height is consistent with hypotheses about trade--offs between morphological and anatomical adaptations that favor efficient water flow through variation in the amount of leaf area supported by sapwood and those imposed by the need to respond quickly to light gaps in the canopy.     

The structure of the upper atmosphere of mars: In situ accelerometer measurements from mars global surveyor

The Mars Global Surveyor (MGS) z-axis accelerometer has obtained over 200 vertical structures of thermospheric density, temperature, and pressure, ranging from 110 to 170 kilometers, compared to only three previous such vertical structures. In November 1997, a regional dust storm in the Southern Hemisphere triggered an unexpectedly large thermospheric response at mid-northern latitudes, increasing the altitude of thermospheric pressure surfaces there by as much as 8 kilometers and indicating a strong global thermospheric response to a regional dust storm. Throughout the MGS mission, thermospheric density bulges have been detected on opposite sides of the planet near 90 degreesE and 90 degreesW, in the vicinity of maximum terrain heights. This wave 2 pattern may be caused by topographically-forced planetary waves propagating up from the lower atmosphere.     

The metabolism of benodanil in the rat

The metabolism of benodanil (2-iodobenzanilide) was studied in rats following an oral dose of 150 mg benodanil kg^?1 body weight. The major 24-h urinary metabolite was found to be the 4′-hydroxy derivative, both free (≈ 5%) and as the glucuronide (≈ 4%) and sulphate (≈ 4%) conjugates. Over a 6-day period, about 16% of the administered dose was excreted in the urine and about 80% in the faeces. After dosing with [¹⁴C]- benodanil, blood radioactivity levels were highest 30 min after dosing, with small broader peaks at 4 and 7 h, while biliary activity levels rose slowly to a maximum about 10–12 h after the dose, some 16% being excreted in 24 h as the glucuronide conjugate of the 4′-hydroxy derivative.     

The metabolism of carboxin in growing barley

The major soluble metabolite of carboxin (2,3-dihydro-6-methyl-5-phenylcarbamoyi-1,4-oxathiin) in barley seedlings and mature plants was identified as the-hydroxy phenyl derivative. This phenol was also bound to the lignin fraction. The distribution of carboxin and its metabolites in seedlings and mature plants grown from treated seed was studied; maximum residues were found in the three oldest internodes, with traces in the roots and flowering heads. Treated plants had altered chlorophyll/carotenoid ratios, and raised levels of some free amino acids.     

Histological and immunohistochemical investigations of ovarian interstitial glands during non‐breeding season in camels (Camelus dromedarius)

The aim of this was to investigate the histology and immunohistochemistry of interstitial glands during non‐breeding season in camel ovaries. A total of 21 mature, non‐pregnant and apparently healthy camels aged between 8 and 12 years were slaughtered. The ovaries were removed within 15 min, cleaned from adipose tissue, weighted and examined grossly. The histological preparation was made, and then, the blocks were cut at 3–5 microns thickness and stained by H&E for histological examinations. Moreover, some sections were stained with Sudan Black for lipid detection. Immunohistochemical analysis of paraffin‐embedded ovarian tissues was performed to detect the localization of S‐100, vimentin, progesterone receptors (PR) and oestrogen receptors (ER). Immunoreactive signals were detected using UltraVision Detection System. The results revealed that the interstitial glands were located in the cortical region and they were arranged in various arrangements either single, in couple or in groups rich in lipid droplet. All interstitial gland arrangements were enclosed by connective tissue capsules containing fibroblasts and collagenous fibres separated them from the surrounding ovarian structures. Both interstitial glands and their surrounding CT were penetrated by several blood vessels. There was a strong immunoreactive signal for S‐100 in the nuclei of interstitial cells, and no signals were detected either in cells of the interstitial glands or their connective tissue with PR. We could conclude that the interstitial gland is distinct in ovary of camel and further studies are needed to elucidate its rule in steroid synthesis.