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Conserving and restoring the Caicos pine forests: The first decade

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Plant Diversity 2019年第2期41卷 75-83页

作者： Michele Dani Sanchez Bryan Naqqi Manco Junel Blaise Marcella Corcoran Martin Allen Hamilton The Herbarium Royal Botanic Gardens Department of environment and Coastal Resources National Environmental Centre

The severe and rapid attack on the Caicos pine Pinus caribaea var. bahamensis(Pinaceae) by the nonnative invasive pine tortoise scale, Toumeyella parvicornis, has resulted in the death of most of the trees in the Turks and Caicos Islands(TCI) in just over a decade. Local and international conservation efforts have enabled the necessary multi-disciplinary research, data gathering, and monitoring to develop and implement a restoration strategy for this endemic tree from the Bahaman archipelago. The native plant nursery established on North Caicos and horticultural expertise acquired throughout the years were crucial to the successful rescue of Caicos pine saplings from the wild populations and cultivation of new saplings grown from locally sourced seeds. These saplings have been used to establish six Restoration Trial Plots on Pine Cay and a seed orchard on North Caicos in TCI. Core Conservation Areas(CCAs) for the Caicos pine forests have been identified and mapped. To date, forest within the Pine Cay CCA has been supplemented by planting more than 450 pine trees, which have survived at a high(>80%)rate.

关键词： Pine forest restoration Plant nursery Pinus caribaea var. bahamensis Caribbean Conservation Turks and Caicos Islands

Synthesis and Structural Characterization of N,N-disubstituted Acylguanidines

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Chinese Journal of Structural Chemistry 2018年第5期37卷 710-718页

作者：王凡凡侯宪辉朱成奔李海普杨鹰 School of Chemistry and Chemical Engineering Centre for Environment and Water Resource Central South University

A series of five N,N-disubstituted acylguanidines R1C（O）N=C[N（H）R2]NR23（R1=Mes or Ph; R2=Ar′′or Ar′; R3=Cy, Bn, iPr, or Et）（Mes=2,4,6-Me3C6H2, Ar′′=2,6-iPr2C6H3, Ar′=2,6-Me2C6H3） was synthesized from the reactions of parent acylthioureas with respective secondary amines. According to structutral characterization by single-crystal X-ray diffraction, the rough reduction of the steric hindrance of R substitutents of R1 C（O）N=C[N（H）R2]NR23（also abbreviated as R1-R2-R3 for comparison purposes） led to the slight enlongation of N（1）–C（1） bond lengthes and small decrease of N（1）–C（1）–N（3） bond angles from Mes–Ar′′–Cy（1） to Ph–Ar′′–Bn（2）, Ph–Ar′′–iPr（3） and Ph–Ar′–Cy（4）. At the same time, the N（1）–H（1）···O（1） intramolecular hydrogen bonds were observed in these cases. When R3=Et, an interesting compound Ph-Ar′-Et（5） was obtained with the formation of intermolecular hydrogen bonds instead. 1 belongs to the monoclinic system, space group P2（1/n） with a=9.6488（3）, b=28.5318（8）, c=11.9155（3） A, b=91.439（2）°, V=3279.27（16） A3, and Z=4. 2 belongs to the triclinic system, space group P1 with a=9.6759（7）, b=10.8613（8）, c=15.7642（12） A, a=70.429（3）, b=79.257（4）, g=69.052（4）°, V=1453.63（19） A3 and Z=2. 3 belongs to the monoclinic system, space group P2（1/c） with a=11.1393（4）, b=13.0643（4）, c=17.6600（6） A, b=101.866（2）o, V=2515.09（15） A3 and Z=4. 4 belongs to the monoclinic system, space group C2/c with a=17.8466（3）, b=13.6126（2）, c=21.6710（4） A, b=90.7310（10）°, V=4992.72（14） A3 and Z=8. 5 is of orthorhombic system, space group P212121 with a=10.5555（2）, b=11.8913（2）, c=14.9558（4） A, V=1877.23（5） A3 and Z=4.

关键词： acylguanidine acylthiourea intramolecular hydrogen bond

Synthesis and Characterization of Copper(Ⅰ) Halide Complexes with Thiourea and Heterocyclic Thione

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Chinese Journal of Structural Chemistry 2015年第10期34卷 1571-1578页

作者：韩立潘霞李海普杨鹰 School of Chemistry and Chemical Engineering Centre for Environment and Water Resource Central South University

Reactions of N,NA-diisopropyl-thiourea（abbreviated as L1） with CuC l2 and Cu Br2 afforded the trimeric（L1Cu Cl）3（1） and（L1Cu Br）3（2）, respectively, featuring the sulfur bridged Cu3S3 six-membered ring each as the core structure. During the reaction, Cu（Ⅱ） was reduced to Cu（I）. Similarly, the reactions of L1 with Cu Cl and Cu Br gave the same products as those by L1 with respective Cu Cl2 and Cu Br2. In contrast, treatment of 1,3-diisopropyl-4,5-dimethylimidazole-2（3H）-thione（L2） with Cu I led to the formation of sulfur and iodide mixed-bridged complex [（L2）4（Cu I）5]（3）, in which two co-vertice Cu3S2 I six-membered rings were fused by an iodide atom. Compounds obtained were characterized by 1H NMR and 13 C spectroscopy, elemental analysis, and single-crystal X-ray diffraction. 2 belongs to the monoclinic system, space group P21/c with a = 19.6009（10）, b = 11.5069（6）, c = 17.1744（9） A, β = 109.062（3）o, V = 3661.2（3） A3, C21H48Br3Cu3N6S3, Mr = 911.18, Z = 4, Dc = 1.653 Mg/m^3, μ（Mo Kα） = 5.192 mm–1, F（000） = 1824, S = 1.030, the final R = 0.0374 and w R = 0.0808 for 4988 observed reflections（I 2σ（I）） and R = 0.0726 and wR = 0.0916 for all data. 3·2THF belongs to the monoclinic system, space group I2/a with a = 19.7335（6）, b = 13.3544（4）, c = 29.6355（11） A, β = 105.415（2）o, V = 7528.9（4） A3, C52H96Cu5I5N8O2S4, Mr = 1945.81, Z = 4, Dc = 1.717 Mg/m^3, μ（Mo Kα） = 3.589 mm–1, F（000） = 3816, S = 1.034, the final R = 0.0325 and w R = 0.0810 for 5704 observed reflections（I 2σ（I）） and R = 0.0447 and wR = 0.0910 for all data.

关键词： thiourea thione S donor copper

Two-day enema antibiotic therapy for parasite eradication and resolution of symptoms

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World Journal of Gastroenterology 2020年第26期26卷 3792-3799页

作者： Niloufar Roshan Annabel Clancy Anoja W Gunaratne Antoinette LeBusque Denise Pilarinos Thomas J Borody centre for Digestive Diseases New South Wales 2046Australia

BACKGROUND Blastocystis hominis(***)and Dientamoeba fragilis(***)are two protozoan parasites of human bowel that are found throughout the *** is still debate about the pathogenicity of these protozoans,despite them being commonly associated with gastrointestinal symptoms and can cause health issue in both children and *** parasites are usually transmitted through faecal-oral contact particularly under poor hygiene conditions or food/water *** a person is infected,the parasites live in the large intestine and are passed in the *** To investigate the effect of triple antibiotic therapy using enema infusion in the treatment of *** and *** *** This retrospective longitudinal study was conducted in a single medical centre,which included fifty-four patients(≥18 years)who were positive for ***,*** or both between 2017 and *** treatment consisted of triple antibiotics that were infused over two consecutive days through rectal *** samples were collected from participants pre-and post-treatment and were tested for parasites using microscopy and polymerase chain ***’symptoms were recorded prior and after the treatment as well as patient demographic *** Patients(n=54),were either positive for ***(37%),***(35%)or both(28%).All patients completed the two-day treatment and no serious adverse effect was *** most common side effect experienced by the patients during the treatment was urine discolouration which was cleared by six weeks of *** symptoms reported prior to treatment were diarrhoea,abdominal pain,constipation and *** symptoms included abdominal discomfort,dizziness and blood in the ***-nine percent of patients completed a final stool test *** six weeks post-treatment,79%of patients cleared the parasites from their *** such as abdominal discomfort,dizziness and blood

关键词： Blastocystis hominis Dientamoeba fragilis Parasitic infection Antibiotics Triple therapy Rectal enema route

A classification of water erosion models according to their geospatial characteristics

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International Journal of Digital Earth 2014年第3期7卷 229-250页

作者： Christos G.Karydas Panos Panagos Ioannis Z.Gitas School of Forestry and Natural environment Aristotle University of ThessalonikiThessalonikiGreece Joint Research centre of the European Commission Institute for Environment and SustainabilityIspraItaly

In this article,an extensive inventory in the literature of water erosion modelling from a geospatial point of view is *** of scale,spatiality and complexity are explored and clarified in a theoretical *** of Geographic Information Systems(GIS)is pointed out as facilitating data mixing and model rescaling and thus increasing complexity in data-method *** scale,temporal scale and spatial methodologies are addressed as the most determining geospatial properties underlying water erosion *** these properties as classification criteria,82 water erosion models are identified and classified into eight *** a result,a complete overview of water erosion models becomes available in a single *** biggest share of the models is found in the category of the mechanistic pathway-type event-based models for watershed to landscape *** parallel,geospatial innovations that could be considered as milestones in water erosion modelling are highlighted and *** alphabetical list of all models is also listed in the *** manipulating scale efficiently,two promising spatial theories are suggested for further exploitation in the future such as hierarchy theory and fractals *** erosion applications,uncertainty analysis within GIS is considered to be necessary for further improving performance of erosion models.

关键词： erosion geospatial model classification digital earth

Numerical evaluation of enhanced green infrastructures for mitigating urban heat in a desert urban setting

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Building Simulation 2023年第9期16卷 1691-1712页

作者： Afifa Mohammed Ansar Khan Mattheos Santamouris Faculty of Built environment University of New South WalesSydneyAustralia Department of Geography Lalbaba CollegeUniversity of CalcuttaKolkataIndia

The cities of desert climates are anticipated to recognize a synergy of urban heat island(UHI)and severe heat waves during *** improve the urban thermal environment,the present study aims quantitatively explore a strategically designed network of vegetation patches called green infrastructure(GI)in subtropical desert cities such as *** achieve a more comfortable temperature environment,we built and simulated four GI situations with higher GI fractions,GI25,GI50,GI75,and *** a mesoscale urban model,the mosaic approach is utilized to test potential thermal improvement and urban climate impact,and a portion of each urban grid cell in the model domain is altered with various species of urban vegetation patches by 25%,50%,75%,and 100%.The daily peak reduction in ambient temperature at 17:00LT is similar to 0.0168℃ per unit of GI increase when compared to the untreated scenario;however,the maximum anticipated daytime summer temperature decline for GI25,GI50,GI75,and GI100 is 0.6℃,1.1℃,1.4℃,and 1.7℃,*** associated reduction in nighttime ambient temperature per unit increase in the GI is 0.0432℃,with a maximum temperature drop of around 2.4℃ for the GI100 *** GI reduces the height of the planetary boundary layer(PBL)by up to 468 m,which might lead to greater pollution *** GI-based cooling has a significant influence on delayed sea breeze and humidity,it may raise the risk of heat discomfort in the indoor building *** study adds to our understanding of the potential for GI mitigation as well as the seasonal impact of developing GIs on the desert urban boundary layer.

关键词： green infrastructure heat mitigation urban heat WRF-SLUCM Dubai city

Do concentrations in eggs and liver tissue tell the same story of temporal trends of mercury in high Arctic seabirds?

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Journal of environmental Sciences 2018年第6期30卷 65-72页

作者： Mark L.Mallory Birgit M.Braune Biology Department Acadia University environment and Climate Change Canada National Wildlife Research Centre Carleton University

Mercury（Hg） remains a key contaminant of concern in Arctic biota, and monitoring of Hg concentrations in seabird tissues will be an effective approach to track the effects of implementing the Minamata Convention. We examined trends in total Hg（THg） in liver and egg tissues of two Arctic seabirds, thick-billed murres（Uria lomvia） and northern fulmars（Fulmarus glacialis）, between 1976 and 2013 to assess whether both tissues showed similar patterns of Hg change. Hepatic THg was consistently higher than egg THg, and both species had similar egg THg concentrations, but fulmars had higher hepatic THg than *** THg concentrations showed more relative variation through time than *** suggest that egg THg better reflects exposure of birds to THg in local, Arctic prey,whereas liver THg may incorporate longer term, year-round THg exposure. Additional analysis of THg distribution in Arctic seabirds post-laying would help inform interpretation of long-term trends.

关键词： Canada Fulmarus glacialis Northern fulmar Thick-billed murre Uria lomvia

Application of nanoparticle tracking analysis for characterising the fate of engineered nanoparticles in sediment-water systems

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Journal of environmental Sciences 2018年第2期30卷 62-71页

作者： Ping Luo Alejandro Roca Karen Tiede Katie Privett Jiachao Jiang John Pinkstone Guibin Ma Jonathan Veinot Alisatair Boxall School of environment Science and Spatial informatics Chinese University of Mining and Technology Department of Physics University of York centre for Chemical Safety and Stewardship (CCSS) Food and Environment Research Agency (FERA) environment Department University of York Department of Chemistry University of Alberta

Novel applications of nanotechnology may lead to the release of engineered nanoparticles（ENPs）, which result in concerns over their potential environmental hazardous impact. It is essential for the research workers to be able to quantitatively characterise ENPs in the environment and subsequently to assist the risk assessment of the ENPs. This study hence explored the application of nanoparticle tracking system（NTA） to quantitatively describe the behaviour of the ENPs in natural sediment-water systems. The NTA allows the measurement of both particle number concentration（PNC） and particle size distribution（PSD） of the ENPs. The developed NTA method was applied to a range of gold and magnetite ENPs with a selection of surface properties. The results showed that the positively-charged ENPs interacted more strongly with the sediment than neutral and negatively-charged ENPs. It was also found that the citrate coated Au ENPs had a higher distribution percentage（53%） than 11-mercaptoundecanoic acid coated Au ENPs（20%） and citrate coated magnetite ENPs（21%）. The principles of the electrostatic interactions between hard（and soft） acids and bases（HSAB） are used to explain such behaviours; the hard base coating（i.e. citrate ions） will interact more strongly with hard acid（i.e. magnetite） than soft acid（i.e. gold）.The results indicate that NTA is a complementary method to existing approaches to characterise the fate and behaviour of ENPs in natural sediment.

关键词： Quantitative characterisation Hard and soft acids and bases Fate of engineered nanoparticles Nanoparticle tracking system Particle number concentration Particle size distribution

Hazards from lakes and reservoirs: new interpretation of the Vaiont disaster

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Journal of Mountain Science 2022年第6期19卷 1717-1737页

作者： Alan P.DYKES Edward N.BROMHEAD centre for Engineering Environment and Society ResearchSchool of Engineering and the EnvironmentKingston UniversityPenrhyn RoadKingston upon ThamesKTi 2EEUK

Hazards in reservoirs and lakes arising from subaerial landslides causing impact waves(or ‘lake tsunamis’) are now well known, with several recent examples having been investigated in detail. The potential scale of such hazards was not widely known at the time of the Vaiont dam project in the 1950s and early 1960s, although a small wave triggered by a landslide at another new reservoir nearby in the Dolomites(northern Italy) drew the possible hazard to the attention of the Vaiont project’s managers. The Vaiont disaster in 1963 arose from a combination of disparate and seemingly unrelated factors and circumstances that led to an occurrence that could not have been imagined at that time. The ultimate cause was a very large landslide moving very rapidly into a reservoir and displacing the water. The resulting wave overtopped the dam to a height of around 175 m and around 2000 people were killed. This paper identifies and examines all of the issues surrounding the Vaiont dam and landslide in order to identify causal factors, contributory factors(including aggravating factors) and underlying factors. In doing so, it demonstrates that the disaster arose from the Vaiont dam project and cannot be attributed simply to the landslide. Underlying geological factors gave rise to the high speed of the landslide, which would have occurred anyway at some time. However, without the contributory factors that account for the presence of the reservoir, i.e. the choice of location for the project and management of the project with respect to a possible landslide hazard, there would have been no disaster. Indeed, the disaster could have been avoided if the reservoir could have been emptied pending further ground investigations. Understanding of this case provides many lessons for future dam projects in mountainous locations but also highlights an ongoing and perhaps under-appreciated risk from similar events involving other water bodies including geologically recent lakes formed behind n

关键词： Vaiont landslide Impulse wave Lake tsunami Dam project Causal factors for disaster