EFFECTS OF MICROBIOME ON CONIFER HEALTH AND RESISTANCE TO BIOTIC AND ABIOTIC STRESS: A SYSTEMATIC REVIEW

ABSTRACT The dynamics of plant-microbiome interactions under different stress conditions are important to understand in order to elucidate the mechanisms underlying forest decline and tree mortality. This study aims to evaluate the importance of ectomycorrhizal fungi in alleviating stress and enhancing defense in Pinus and Picea species. A meta-analysis was performed on primary research articles that assessed effects of ectomycorrhizal fungal on growth and resistance of these tree species. The stress factors studied were drought, pathogen infection, herbivory and pollutant stress. A PRISMA systematic review guideline was used in screening the articles from the two databases Web of Science and SCOPUS. The search produced a total of 1 806 articles, which were further screened by excluding review articles, book chapters, conference papers and other papers that did not include Pinus or Picea species and ectomycorrhizal fungi. A total of 118 articles were assessed and the statistical analysis was conducted as per factor (growth, survival, biotic and abiotic stress). Most of the published articles were on Pinus and a few on Picea. Overall, ectomycorrhizal fungi were found to enhance growth but had no effect on survival, though the results are more confined to Pinus species. Ectomycorrhizal fungi were not effective in alleviating abiotic and biotic stress. There was high heterogeneity among papers and publication bias in the analysis. As a result my analysis did not provide a concrete conclusion in endorsing ectomycorrhizal fungi as promoting conifer growth, survival and resistance to biotic and abiotic stress. Further research is needed on conifer- soil feedbacks in relation to ectomycorrhizal fungi. Moreover, there is need for conducting more experiments in the field to enable the life strategies of ectomycorrhizal fungi to be brought into sharper focus. This is important because conifer species are of high economic value through producing high quality timber and plays a crucial role in mitigating climate change. Key words: Ectomycorrhizal fungi, Pinus, Picea, heterogeneity, publication bias, growth, survival, biotic and abiotic

The Alkaloidal Constituents of Gelsemium sempervirens With an Additional Paper: Fission and Molecular Rearrangement as Alternate Modes of Reaction

The starting material for this investigation consisted of 22.5 kilograms of the dry powdered root of Gelsemium sempervirens, Aiton, and the object of the work was the isolation of the alkaloidal constituents of the root, followed by their chemical investigation. On account of the fact that sempervirine is unstable to heat, and is resinified to a large extent in boiling alcohol, it was decided, after some preliminary experiments, to carry out an extraction first of all with cold rectified spirit, followed by an extraction with boiling alcohol. It was decided also to use the method of separation (14) devised by Sayre for the isolation of gelsemine, sempervirine, and the amorphous alkaloids, and also to attempt the isolation of gelsemicine from the gelsemine mother liquors as described by Chou (15) , with certain small modifications in each case. This was done and the yields of gelsemine and sempervirine were found to be very much larger than those recorded by Sayre, particularly in the case of the latter. This was due, presumably, to the employment of a cold alcoholic extraction. The yield of gelsemine obtained was 0. 13% compared with 0.07% recorded by Sayre (14) and that of sempervirine (as nitrate) was 0.084% compared with 0.026% reported by Sayre. A small quantity of an amorphous alkaloid, not previously reported, was found in the gelsemine fraction, but could not be obtained crystalline. This alkaloid was found to be very slightly soluble in water and alcohol on long heating. The melting point of this amorphous alkaloid is 324d. An amorphous piorate was formed from water but could not be crystallised. On evaporating this alkaloid to dryness with hydrochloric acid a crystalline hydrochloride was formed, melting above 340, but owing to the extreme solubility of this hydrochloride and the small amount available, it was not found possible to prepare a sufficient quantity of the pure material for analysis determinations. Prom the fraction of the amorphous alkaloids called gelsemoidine by Sayre, there has been isolated a crystalline methiodide not previously reported. Analysis figures for this methiodide indicate a formula of either C20H24O3N2. CH3I or C20H22O3N2. CH3I. The melting point of this methiodide suggests its identity with apogelsemine methiodide C20H24O3N2. CH3I (melting points 296-297d. and 295d. respectively), but the determination of its specific rotation would seem to discount this view. The value Moore (11) has found for the specific rotation of apogelsemine methiodide is [x]D+12.4. An attempt was made to repeat, as far as possible, the conditions employed by Moore for apogelsemine methiodide, for the determination of the specific rotation of "gelsemoidine" methiodide. This has, however, been found impossible, the new methiodide being less soluble in water than apogelsemine methiodide has been recorded to be. A saturated solution was used for the determination and a value of [a]20D +3.9 was found. For comparison purposes the specific rotation of gelsemine methiodide was determined, and found to differ slightly from Moore's value. The value found was [a]10D+6.0, compared with that of [a]D +8.9 recorded by Moore(10). These results for gelsemine methiodide are in much closer agreement than those for "gelsemoidine" methiodide and apogelsemine methiodide, and it seems possible that the methiodide isolated from the gelsemoidine fraction is not, in fact, identical with apogelsemine methiodide. This possibility is, to a certain extent, enhanced by the fact that neither Sayre nor the present author were able to obtain "gelsemoidine" hydrochloride in the crystalline state, whereas apogelsemine hydrochloride is a crystalline substance. No attempt was made to prepare apogelsemine methiodide for comparison purposes as, for the isolation of pure apogelsemine, a relatively large expenditure of gelsemine would have been involved. The attempted isolation of gelsemicine was not successful, this fraction consisting of a dark brown tarry material which contained some gelsemine

Units of appreciation in general science

Thesis (M.A.)--Boston University, 1929. This item was digitized by the Internet Archive

Ineffective Aggregation of Filipino-American Health Assessment Data & It\u27s Effect on Individualized Healthcare

Background Filipino-Americans and their health care data seem to be difficult to find individually, and this is due to the continual grouping of this population with other Asian subgroups into the Asian-American population. The needs of the Filipino-American population are distinctly different from other Asian-American subgroups, and the underrepresentation leads to inadequate health care, lack of education within the community, and in some cases, disproportional deaths of Filipino-Americans. Objective To highlight the importance of adequate aggregation of health assessment data of a specific population on individualized care, in this paper, Filipino-Americans. Summary of Findings In the review of literature, it seems that aggregation of health assessment data specifically for Filipino-Americans depict major issues that may not reflect on the majority of the Asian-American population. The inadequate aggregation of Filipino-American healthcare data is also comparable to the experiences of Filipino-Canadians, who also face a similar issue in their country. Proposal Through a mixed-method study, the researchers aim to identify some of the more prominent health disparities of Filipinos in America, research possible interventions for those disparities, and create ways to prevent inadequate aggregation of Filipino-American healthcare data

A Macroporous TiO2 Oxygen Sensor Fabricated Using Anodic Aluminium Oxide as an Etching Mask

An innovative fabrication method to produce a macroporous Si surface by employing an anodic aluminium oxide (AAO) nanopore array layer as an etching template is presented. Combining AAO with a reactive ion etching (RIE) processes, a homogeneous and macroporous silicon surface can be effectively configured by modulating AAO process parameters and alumina film thickness, thus hopefully replacing conventional photolithography and electrochemical etch methods. The hybrid process integration is considered fully CMOS compatible thanks to the low-temperature AAO and CMOS processes. The gas-sensing characteristics of 50 nm TiO2 nanofilms deposited on the macroporous surface are compared with those of conventional plain (or non-porous) nanofilms to verify reduced response noise and improved sensitivity as a result of their macroporosity. Our experimental results reveal that macroporous geometry of the TiO2 chemoresistive gas sensor demonstrates 2-fold higher (∼33%) improved sensitivity than a non-porous sensor at different levels of oxygen exposure. In addition, the macroporous device exhibits excellent discrimination capability and significantly lessened response noise at 500 °C. Experimental results indicate that the hybrid process of such miniature and macroporous devices are compatible as well as applicable to integrated next generation bio-chemical sensors