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The dark bridal canopy.

Physician narratives in family medicine have the potential to convey the vibrant spirit of our field and provide meaningful insights into disease, illness, suffering, and the nature of healing. They may also complement empirical research, education, and practice through their integrative, expressive nature. This true story depicts a challenge faced by the author while serving as a family physician in a desolate, desert region in Israel's southern Aravah Valley (south of the Dead Sea), where he was privileged to practice for a decade. The episode, a fatal car crash in which a newlywed Druse woman (a member of a secretive sect) was killed, involved much more than just the terse details listed in the emergency log. An example of a family medicine physician-and-self drama, this piece takes the reader beyond the basic medical facts into the experience and sensations of the event. It also provides a stark contrast to the usual medical description and emphasizes the importance of stories as reflective opportunities for improving health care, sustaining ourselves as practitioners, and maintaining the vitality of our field.

Adult↗

New Tachinidae (Diptera) host records of eastern North American forest canopy Lepidoptera: baseline data in a Bacillus thuriengiensis variety kurstaki nontarget study.

Macrolepidopteran caterpillars collected in 1995 and 1996 in the Monongahela National forest, Pocahontas County, WV, and the George Washington National forest, Augusta County, VA, yielded 60 previously unreported tachinid host associations. Most associations were between native species, but the introduced polyphagous tachinid Compsilura concinnata (Meigen) produced eight new associations with native hosts. The tachinids collected were slightly broader in their host preferences than associated Braconidae and Ichneumonidae, illustrating their potential importance in regulating foliage-feeding macrolepidopteran populations in the region studied. The sample years reported herein are the pretreatment baseline portion of a long-term study on the effects of Lymantria dispar (L.) defoliation, efficacy of applied Bacillus thuringiensis variety kurstaki Berliner, and the natural occurrence of the L. dispar pathogen Entomophaga maimaiga Humber, Shimazu & Soper on nontarget organisms.

Animals↗

[A research review on "fertile islands" of soils under shrub canopy in arid and semi-arid regions].

Due to the inclemency of climate and soil conditions and the intense disturbance of human beings, the soil resources heterogeneity in arid and semi-arid grassland ecosystems worldwide was gradually increased during the last century. The interaction between soil heterogeneity and shrubs induced the autogenic development of "fertile islands" and the increasing spread of shrubs in the grassland ecosystems. The development of "fertile islands" around individual shrubs could change the vegetation composition and structure, as well as the distribution patterns of soil resources, and thus, reinforced the changes of the ecosystem function and structure from a relative stable grassland ecosystem to a quasi-stable shrubland ecosystem. The study of "fertile islands" phenomenon would help us to understand the causes, consequences and processes of desertification in arid and semi-arid areas. In this paper, the causes of "fertile islands", its study methods and significance and its relationship with shrub spreading as well as the responses of vegetation to it were summarized. The problems which might occur in the study of this phenomenon were also pointed out. Our aim was to offer some references to the study of land desertification processes and vegetation restoration in the arid and semi-arid regions.

Desert Climate↗

Hypomelanotic canopy of sarcoidosis.

A case of cutaneous hypopigmented macules localized above deep dermal and subcutaneous sarcoid granulomas in a patient with systemic sarcoidosis is presented. Melanin was only sparsely distributed in the upper stratum malpighii. Hypopigmentation is an unusual manifestation of sarcoidosis. With an armamentarium of clinical observation, dermatologists may suspect a hypomelanotic cutaneous diadem overlying a palpable dermal mass to be a visual vignette of a sarcoidal montage requiring diagnostic biopsy.

Adult↗

Interception loss, throughfall and stemflow chemistry in pine and oak forests in northeastern Mexico.

Interception loss, gross precipitation, throughfall and stemflow solution chemistry beneath pine (Pinus pseudostrobus Lindl.), oak (Quercus sp.) and pine-oak natural forest canopies in northeastern Mexico were measured. Coefficients of variation for throughfall were 12% in pine and oak canopies and 17% in the mixed pine-oak canopy. The variability of stemflow averaged 66, 126 and 73% for pine, oak and the mixed pine-oak canopies, respectively. Linear regression analysis of net versus gross precipitation for the three canopies showed highly significant correlations (r = 0.974-0.984). Total precipitation during the experimental period was 974 mm and estimated interception loss was 19.2, 13.6 and 23% for the pine, oak and pine-oak canopies, respectively. Stemflow did not occur following rainfall events of less than 4 mm and, in all canopies, stemflow represented a minimal proportion of gross precipitation (0.60, 0.50 and 0.03% for pine, oak and pine-oak, respectively). Throughfall pH in pine (6.2), oak (6.3) and pine-oak (6.3) canopies was significantly more acidic than gross precipitation (6.6). Stemflow pH ranged from 3.7 (pine) to 6.0 (oak). The pine-oak canopy registered the highest throughfall and stemflow electrical conductivities, 104 and 188 microS cm(-1), respectively. Net nutrient leaching of K, Mg, Na, Fe, Mn and Zn was significantly higher from the pine-oak canopy than from the pure pine and oak canopies. Mean depositions of Ca and Cu in throughfall behaved similarly among the three types of canopies. A greater proportion of Zn in gross precipitation was absorbed by the oak canopy than by the pine and pine-oak canopies. Enrichment factors beneath the pine-oak canopy relative to gross precipitation varied from 1.2 to 3.2 for macro-nutrients (Ca, K, Mg and Na) and from 1.4 to 3.1 for micro-nutrients (Cu, Fe, Mn and Zn). Stemflow depositions of Ca, K, Mg and Cu were higher in the pine-oak canopy, whereas stemflow depositions of Na, Fe, Mn and Zn were higher in the pine canopy.

Mexico↗

Branchlet nutrient concentration in hoop pine (Araucaria cunninghamii) relative to family, stable carbon and oxygen isotope ratios and growth rate in contrasting environments.

Genetic variation in branchlet nutrient (N, P, K, Na, Ca, Mg, Mn and Fe) concentrations and mineral concentration (sum of branchlet P, K, Na, Ca, Mg, Mn and Fe concentrations) of 8-9-year-old hoop pine (Araucaria cunninghamii Ait. ex D. Don) half-sib families was assessed for four canopy positions at a wet site (23 families) and two canopy positions at an N- and water-limiting dry site (22 families) in relation to tree growth and associated branchlet carbon (delta13C) and oxygen (delta18O) isotope composition in southeast Queensland, Australia. Branchlet nutrient and mineral concentrations varied significantly among families and with canopy position and site. Depending on the canopy position sampled, the hoop pine family effect accounted for 0 to 13.8% of the total variation in branchlet N concentration, and for 0 to 30.3% of the total variation in branchlet mineral concentration at the wet site. The corresponding values for the family effect at the dry site were 0-13.3% for branchlet N concentration and 0-25.7% for branchlet mineral concentration. There were significant variations in branchlet P, K, Ca and Mg concentrations at both sites, and these variations differed with canopy position. Relationships between family means of branchlet N concentration and tree growth or delta13C or delta18O varied with canopy position at both sites. At the wet site, there were significant positive correlations between branchlet mineral concentration in the upper-outer or upper-inner canopy and tree height (r = 0.26 and 0.37, P < 0.01) and between branchlet mineral concentration and delta13C (r = 0.24, P < 0.01) in the upper-inner canopy, and a significant negative correlation between branchlet mineral concentration and delta13C (r = -0.21, P < 0.05) in the upper-outer canopy. At the dry site, branchlet mineral concentrations in the upper-inner and upper-outer canopy were significantly correlated with branchlet delta13C (r = -0.28 and -0.51, P < 0.01), and branchlet N concentration in the upper-inner canopy was significantly correlated with tree growth (r = 0.29, P < 0.01). A significant correlation between branchlet delta18O (an index of stomatal conductance) and branchlet mineral concentration at the dry site (r = 0.39, P = 0.020) indicated that stomatal conductance might be a factor regulating the variation in branchlet mineral concentration of the hoop pine families. Both branchlet N concentration and mineral concentration at particular canopy positions assist in selecting hoop pine families with improved tree growth and N- and water-use efficiency in environments where both N deficiency and a limited water supply are major factors affecting plantation productivity.

Carbon↗