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PubMed2001

[Tree stomatal infiltration and SO2 injury and protection effect of ABA].

This paper deals with relation between tree stomatal infiltration and SO2 injury and the protection effect of ABA. Experiments of SO2 smoking to the selected trees were carried out and the data were collected in the field. The results show that stomatal infiltration was a comparably constant index for certain tree species. The infiltration of trees is negatively correlated with the combine extent of chlorophy, but not obviously. The index is also positively correlated with K+ efflux in leaf(r = 0.92, alpha < 0.01). In the experiment of SO2 smoking, the effect on infiltration of same species under different SO2 concentration was little, less than one grade, while K+ efflux increased with the increment of SO2 amount absorbed by the leaves. When the leaves were sprayed with ABA solution, the higher the ABA solution concentration was, the lower the K+ efflux was. When leaves sprayed with ABA solution were smoked with 2.5 mol.L-1 for four hours, the infiltration of leaves with 30 mol.L-1 ABA solution dropped 1.5-3 and K+ concentration decreased 36.5%-54.8% on leaves. It indicates that the ABA solution on leaves has remarkable effect of protection of SO2 injury.

Abscisic Acid↗

PubMed2000

[Tree species diversity in gaps of different sizes and developmental stages in lower subtropical evergreen broadleaved forest, South China].

The change pattern of tree species diversity in gaps of different sizes and developmental stages in the lower subtropical evergreen broadleaved forest was analyzed in this paper. The species diversity index(Shannon-Wienner) did not change in the gaps with a size of < 400 m2, reached the highest in those with a size of 400-500 m2 and the lowest in the gaps of 500-600 m2 size, and increased in those with a size of > 600 m2. The index was the highest in the middle period of 20-50 years, secondly high within 20 years, and lowest after 50 years of gap formation. The species diversity in regeneration layer(H < 1.5 m) reached a peak in the gaps with a size of 500-600 m2, and the lowest values occurred at the gaps with a size of > 600 m2 and 200-300 m2. Species diversity index in the regeneration layer reached the highest in the first 10 years after gap formation, then revealed a general trend of decreasing, but two relative peaks were formed in the gap ages of about 30-40 years and 50-60 years, respectively. The general trends of species richness were correspondent with those of species diversity index. Gaps of different sizes and ages had a strong influence on the tree species regeneration through changes of ecological factors in gaps, thus, tree species diversity was different in gaps of different sizes and ages. Gap is one of the most important mechanisms for the maintenance of tree species diversity in the lower subtropical evergreen broadleaved forest.

China↗

PubMedDate not supplied

[Correlation of the width of annual tree rings with climatic changes and solar activity].

Fluctuations in the width of annual tree rings in the time interval from the eighth century till the present time were analyzed on the basis of dendroclimatic scales. Periods of extremely high and low growth of trees were distinguished, and their correlations with heliogeophysical factors were studied. The major climatic parameters determining the growth of trees are warmth and moisture; a small gain is observed in cold and droughty periods. No correlations between the width of tree rings and the minima and maxima of solar activity cycles were observed with the method used.

Climate↗

PubMed2004

Spinal cord injuries due to falls from hunting tree stands in Oklahoma, 1988-1999.

Serious injuries resulting in paralysis or death have been shown to occur to hunters who have sustained falls from tree stands. A total of sixteen spinal cord injuries or deaths among Oklahoma hunters falling from tree stands were reported between 1987 and 1999. The mean height of the falls was 16.4 feet. Three (18.8%) of the cases were related to substance use. None of the patients were using a safety restraint. Nearly 90% of the injuries resulted in paraplegia/paresis; two (12.5%) of the injuries resulted in death. Forty-four percent of the spinal injuries occurred at the thoraco-lumbor junction (T12 or L1). Burst fractures were the most common fracture pattern. Hospitalizations averaged 19.6 days (range 3 to 73 days) and eight (50%) were discharged to inpatient rehabilitation facilities. Falls from tree stands can result in serious injuries or death. Hunter education and the use of safety harnesses for prevention of injuries related to tree stands are paramount.

Accidental Falls↗

PubMed2004

Diurnal and seasonal variability in the radial distribution of sap flow: predicting total stem flow in Pinus taeda trees.

We monitored the radial distribution of sap flux density (v; g H2O m(-2) s(-1)) in the sapwood of six plantation-grown Pinus taeda L. trees during wet and dry soil periods. Mean basal diameter of the 32-year-old trees was 33.3 cm. For all trees, the radial distribution of sap flow in the base of the stem (i.e., radial profile) was Gaussian in shape. Sap flow occurred maximally in the outer 4 cm of sapwood, comprising 50-60% of total stem flow (F), and decreased toward the center, with the innermost 4 cm of sapwood (11-15 cm) comprising less than 10% of F. The percent of flow occurring in the outer 4 cm of sapwood was stable with time (average CV < 10%); however, the percentage of flow occurring in the remaining sapwood was more variable over time (average CV > 40%). Diurnally, the radial profile changed predictably with time and with total stem flow. Seasonally, the radial profile became less steep as the soil water content (theta) declined from 0.38 to 0.21. Throughout the season, daytime sap flow also decreased as theta decreased; however, nighttime sap flow (an estimate of stored water use) remained relatively constant. As a result, the percentage of stored water use increased as theta declined. Time series analysis of 15-min values of F, theta, photosynthetically active radiation (PAR) and vapor pressure deficit (D) showed that F lagged behind D by 0-15 min and behind PAR by 15-30 min. Diurnally, the relationship between F and D was much stronger than the relationship between F and PAR, whereas no relationship was found between F and theta. An autoregressive moving average (ARIMA) model estimated that 97% of the variability in F could be predicted by D alone. Although total sap flow in all trees responded similarly to D, we show that the radial distribution of sap flow comprising total flow could change temporally, both on daily and seasonal scales.

Circadian Rhythm↗

PubMed2005

Formulation and evaluation of an effective pH balanced topical antimicrobial product containing tea tree oil.

The effect of pH on the antimicrobial activity of Melaleuca alternifolia essential oil formulations was studied. Microemulsions, liposomal dispersions, multiple emulsions and a colloidal bed of sterile clay were formulated using 5% w/w of tea tree oil. A number of formulations were prepared at various pH values (5.0, 5.5, 6.0, 6.5, and 7.0). Thermal stability studies showed that the formulations were stable for more than eight months. Agar dilution tests showed MICs of 1.0% v/v S. aureus and S. epidermidis. In the broth dilution test, MBC of the oil for P. acnes was 0.5% v/v. MIC and MBC values were comparable to those of non-formulated tea tree oil, indicating that tea tree oil retained its activity in the above-mentioned formulations. The microbiological evaluation showed that the formulations containing 5% w/w tea tree oil had a maximum effect at pH 5.5.

Acne Vulgaris↗

PubMed2005

[Growth responses of four northern broadleaved tree species to soil Cd stress].

In this paper, the gradient (0, 10, 50, 100, 200 mg x kg(-1)) of soil Cd concentrations was established by mixing CdCl2 with soil and sand, and the growth responses of four northern broadleaved tree species Acer ginnala Pyrus ussuriensis, Acer mono and Malus baccata to soil Cd contamination were studied by growing their seedlings in pots in greenhouse. The results revealed that the seedling growth of all test species was enhanced under lower soil Cd concentrations (< or = 50 mg x kg(-1)), and Acer ginnala had the strongest response under 10 mg x kg(-1) treatment, with 135.8% and 146.0% increment of collar and height growth, respectively, in comparing with the control. But, the growth of aboveground part decreased with increasing soil Cd, and the collar and height growth of A. ginnala under the highest Cd concentration was only 24.1% and 28.0% of the control, respectively. Under lower Cd concentrations, an increase of foliage and new shoot growth was found in A. ginnala and P. ussuriensis, the biomass of new shoots increased but that of foliage decreased in M. baccata, and both foliage and new shoot decreased in A. mono. Under the highest Cd concentration, A. ginnala had the greatest decrease of foliage and new shoot biomass, being 4.6% and 7.3% of the control, respectively, while P. ussuriensis and M. baccata had a relatively less decrease. The biomass increase of new roots declined with increasing Cd concentration for all tree species except P. ussuriensis, and the least increase was A. ginnala, only 2.3% of the control. The new root biomass of P. ussuriensis was 125.5% and 117.1% of the control at 10 mg and 20 mg x kg(-1), respectively. The total biomass increment of A. ginnala and P. ussuriensis seedlings was greater than that of the control under lower Cd concentrations, while an obvious decrease was found for all tree species under higher Cd concentrations. Under the highest Cd concentration, the total biomass of A. ginnala, M. baccata, A. mono and P. ussuriensis was 13.7%, 27.2%, 36.4 and 40.1% of the control, respectively. Subordinate function analysis suggested that the tolerance of test tree species to soil Cd contamination was in order of M. baccata > A. ginnala > P. ussuriensis > A. mono. Analysis of Cd concentration in plant tissues demonstrated that P. ussuriensis had the highest Cd enrichment coefficient for its root, shoot and foliage, and M. baccata also had a higher Cd enrichment in its root and shoot.

Acer↗

PubMedDate not supplied

[The role of historical processes in determining tree species richness in the forests of Western Caucasus].

To estimate the role of history in variation of tree species richness in the forests of the Western Caucasus we analyzed correlation between their local richness (S--the mean number of species per 300 m2) and size of actual species pool (N--the number of species per 1 ha). If compared communities are differently distant from the point of evolutionary equilibrium one should expect a significant variation in correlation between S and N (determined with the greater sensitivity of N than S in respect of historical factors). The lower value of N/S corresponds to less saturated level of historically determined species richness. A mean N/S ratio in Japana temperate broadleaved forests (Masaki et al., 1999) provided the basis for analysis. The present tree species richness of the forest communities in the 1 ha plots seem essentially determined by the historical processes. The mountain forest communities of Western Caucasus are characterized on the average with lower saturation level of the actual tree species pool in comparison with the Japan temperate broad-leaved forest communities. On the Western Caucasus the middle mountain beech and coniferous-broadleaved communities (400-1600 m a.s.l.) are characterized with the higher saturation level of the actual species pool in comparison with communities located lower and higher. These results confirm published historical reconstructions, according to which the middle mountain forest communities in the Western Caucasus are older than forests located higher or lower. Present low mountain forests of the southern (to Black Sea) and the northern macroslopes of the Western Caucasus are characterized with similar saturation level of the actual species pool. These data agree with the assumption of Dolukhanov (1980) that low mountain zone of the southern macroslope was not a refuge for tree species in Pleistocene.

Biological Evolution↗

PubMed2006

[Introduction to ethnographic decision tree modeling].

With rapid advances in healthcare technology, patients are increasingly compelled to make medical decisions in unfamiliar and highly stressful situations. Nurses, therefore, have a responsibility to understand the medical options, and consequences of each, in order to help patients make the best decisions for themselves. Ethnographic decision tree modeling is a research "triangulation" tool conducted in two stages. The first stage uses ethnographic fieldwork techniques to determine the criteria used by insiders (i.e., decision makers) to make a real-world decision. These criteria are combined into a decision tree. The second stage applies a quantitative research method to verify the degree of predictive accuracy of the decision tree. This method addresses the meaning and predictability of decision-making. This paper introduces ethnographic decision tree modeling and provides a perspective on inquiring about the bases of patient decision-making.

Anthropology, Cultural↗

PubMed1990

[IgG4 antibodies to the allergens of grass and tree pollens in pollinosis patients: their diagnostic and prognostic significance].

Total IgE, IgE and IgG4 antibodies to offending allergens were studied in 118 hay fever patients with allergy to tree pollen or to grass pollen. No difference in the level of total IgE and IgE antibodies was found between these groups of patients while the IgG4 antibody level was significantly higher in tree pollen-allergic patients. It has been established that in tree pollen allergy, the determination of IgG4 antibodies is of no less diagnostic value than the assay of IgE antibodies. The authors discuss the problems of the prognostic value of IgG4 antibody increase during the hyposensitization therapy and of a possible relationship between IgG4 antibodies and allergy to vegetable food often associated with tree pollen allergy.

Allergens↗

PubMed2006

[Correlations between diagnostic information and therapeutic efficacy in rheumatoid arthritis analyzed with decision tree model].

OBJECTIVE: To explore the correlations between diagnostic information and therapeutic efficacy in rheumatoid arthritis (RA) with decision tree model analysis. METHODS: Three hundred and ninety seven patients came from 9 clinical centers were randomly divided into the Western medicine (WM) group (n=194) treated with non-steroidal anti-inflammatory drugs and slow-acting antirheumatic drug and the Chinese medicine (CM) group (n=203) with basic therapy and syndrome-differentiation dependant TCM treatment. TCM and WM diagnostic information were collected. The ACR 20 was used for efficacy evaluation and the information of patients before treatment was analyzed by SAS 8.2 statistical package. Through single-factor exploratory analysis, odds ratio of efficacy and variable was calculated taken P < 0.2 as the including criteria for data mining analysis with decision tree model. All data were classified into the training set (75%) and verifying set (25%) with efficacy as the variable for layering to make further verification of the data-mining analysis. RESULTS: Twenty variables were included in the CM group and 26 in the WM group in the data-mining model. In the former, 9 variables were positively correlated to the efficacy, including degree of arthralgia, tenderness and morning stiffness, number of swollen joint, and joint with tenderness, levels of IgM, rheumatoid factor (RF), C-reactive protein (CRP), and total assessment from doctor; and disease duration and degree of nocturnal polyuria were negatively correlated to that. While in the latter, 8 were positively correlated to the efficacy, including erythrocyte sedimentation rate (ESR), sour and weak waist and knees, white fur in tongue, joint ache and stiffness, swollen joint, and total assessment from doctor and patient, and red tongue with yellow fur and leucocyte count negatively correlated to it. Data mining with decision tree analysis revealed that different combinations of morning stiffness, slight red tongue, joint tenderness and nocturnal polyuria in the CM group, and those of white fur in tongue, CRP level, leucocyte count and morning stiffness in the WM group showed different efficacy, which were also verified in the randomly chosen verifying set. CONCLUSION: To analyze the correlations between diagnostic information and therapeutic efficacy with decision tree analysis is conformed to the theory of TCM in applying treatment according to syndrome differentiation individually, thus it would contribute to elevate the accuracy of therapy.

Adolescent↗

PubMed2006

[Study on the application of classification tree model in screening the risk factors of malignant tumor].

OBJECTIVE: To introduce the partitioning algorithm of classification tree model, and to explore the value of this data mining technique applied in data analysis of multifactorial diseases as malignant tumors. METHODS: Data was analyzed from a survey that conducted on 84 breast cancer patients and 273 cancer-free controls selected randomly in Jiashan county. The classification tree model was constructed using Exhaustive CHAID method and evaluated by the Risk statistics and the area under the ROC curve. RESULTS: 9 out of 105 effect risks factors were selected, in which career was the most important factor indicating that workers, teachers and retirees suffered much more risks than others. Nevertheless, the number of pregnancies, breast examination, reasons for menopause, age at menarche, intake of shrimp, crab, kipper, kelp and laver etc were also risk factors on breast cancer. However, physical exercise played different roles on different people. The Risk statistics of model was 0.174, and the area under the ROC curve was 0.872 which was significantly different from 0.5, suggesting that the classification tree model fit the actuality very well. CONCLUSION: The classification tree model could screen out the major affecting factors quickly and effectively and could also identify the cutting-points for continuous and ordinal variables, as well as revealing the complex interaction among the factors at many levels. This model might become a powerful tool to explore the complexities of the risks on diseases.

Algorithms↗

PubMed1991

Airborne pollen survey for Lincoln, Nebraska: I. Trees.

Pollen counts in 1988, 1989, and 1990 revealed 14 different tree pollen types. The main tree pollination season in Lincoln extends from late February or early March through the end of May. First linden and then pine and juniper extend the trees through October. The sequence of flowering for the plants is similar to that found in other regions of the country. The highest counts (peaks of ca. 1000 grains/m3) are in March, April, and May when the largest number of trees are in bloom. Counts fall through June (highest ca. 300 grains/m3) and July (highest at ca. 35 grains/m3) when grasses and some weeds are flowering.

Air Pollution↗

PubMed1989

[Construction of a decision tree for preoperative diagnosis in urinary incontinence].

In order to analyse the decisions used in non-urodynamic preoperative diagnosis of female urinary incontinence we constructed a decision tree, consisting of decision nodes and probability nodes. Each branch of the decision tree leads to an end point (terminal node), to which an utility must be assigned. We describe the different steps in the construction of the decision tree: 1. listing of all possible decisions (questionnaire, clinical stress test, both, no preoperative tests), 2. assignment of probabilities to the different events (e.g. cure, failure, operation in the absence of genuine stress incontinence), and 3. assignment of utility factors to the end points. We used previously published probabilities from our clinic, utility was assigned arbitrarily using a score from -10 to +90. The decision tress allows not only the calculation of the strategy with the highest expected utility, but also threshold analysis, sensitivity analysis and cost-benefit analysis. We feel that decision trees are valuable tools for analysing how medical decisions are reached and are particularly useful in teaching situations.

Adult↗

PubMed1995

Mountain cedar allergens found in nonpollen tree parts.

BACKGROUND: Mountain cedar (Juniperus ashei) pollen is the principal aeroallergen in south central Texas from late December through February. The major mountain cedar allergen is a 40-kD glycoprotein, gp40. OBJECTIVE: To identify allergens in mountain cedar wood, leaves, and berries and to detect mountain cedar allergen in smoke from burning male or female trees. METHODS: SDS-PAGE plus mountain cedar human sIgE and monoclonal antibody immunoblots identified mountain cedar allergens within pollen and nonpollen tree part extracts. RESULTS: IgE immunoblots identified a single wood allergen at 36 kD and three berry allergens at 36, 26-27, and 21 kD, in addition to known pollen allergens. Mountain cedar monoclonal antibody bound an allergen epitope present not only on 40, 33, and 28-kD pollen allergens, but also on 36 and 32-kD wood allergens, and the 26-27-kD berry allergen. Immunoblot studies detected no mountain cedar allergen in leaves and no allergen in smoke from burning male and female trees. Allergens constituted a much smaller percentage of extractable protein in wood and berries than in pollen. CONCLUSIONS: Mountain cedar berry allergen content is too small to give credence to the ingestion of berries as a folk medicine treatment of mountain cedar pollinosis. In addition, while smoke from burning mountain cedar trees may be irritating, it contains no allergens that could cause allergic rhinoconjunctivitis.

Allergens↗

PubMed1994

[Allergic contact eczema due to 'tea tree' oil].

In four patients, three women aged 45, 29 and 52 years and a man aged 45 years, allergic contact dermatitis due to 'tea tree' oil was diagnosed. The case of the man was published before. 'Tea tree' oils are essential oils distilled from the leaves of myrtaceous trees and shrubs occurring in Australia and South-East Asia. The 'tea tree' oil available in the Netherlands is distilled from the Melaleuca alternifolia and mainly contains eucalyptol. Eucalyptol is probably the most important allergen.

Adult↗

PubMed1993

Constructing a minimal diagnostic decision tree.

Classification trees and discriminant function analysis were employed in order to ascertain whether a small number of diagnostic decision rules could be extracted from a large inventory of items. Several models, involving up to 17 symptoms, that led to a broad psychiatric diagnosis were then tested on a small validation sample of 53 patients. All methods, with the exception of CART used without any pruning, generated identical trees involving four items. Almost 90% of the validation sample was able to be correctly classified by all methods although poor classification performance was noted in the case of one particular diagnosis, Schizoaffective Psychosis. In contrast, stepwise linear discriminant analysis originally selected 17 items, although three out of the first four items selected were identical to those chosen by the tree-building methods. Although more research is required, there are indications that the latter methods may be usefully employed in constructing parsimonious decision trees.

Algorithms↗

PubMed1993

[Aeropollinologic and allergologic studies for the clarification of "poplar tree hay fever"].

The authors performed allergen research on patients reported hay fever symptoms during the poplar pollen season (March), and in patients with hay fever symptoms during the time of the year that the seed hairs of the poplar trees are blowing in the air (May). Skin prick tests (Epipharm) and serum specific IgE tests (Epignost IgE Quick and Phadezym Populus deltoides RAST, Pharmacia) were performed on the basis of the pollen calendar of Szeged region on 30 patients. The pollen containt of the air was measured by means of a Lanzoni sampler. According to the pollen calendar of our region a large amount of grass pollens could be found in the air at the same time as the seed hairs of poplar trees are present (in May). The season of poplar pollen is in March in this area. Poplar pollen sensitivity was found on 8 patients. This is 6.8% of the total number of hay fever patients. They were found to be sensitive to other tree pollens too. The 23 patients complaining about hay fever symptoms in May, during the flaying of the cottons of the poplar trees in the air were all found to be sensitive to grass pollens. On the basis of our results the poplar pollen sensitivity is a relatively rare cause of hay fever. Our patients having complained about the seed hairs were all found to be sensitive to grass pollens. It seems that the grass pollens are the real cause of their disease.

Allergens↗