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Early onset of a microcystin-producing cyanobacterial bloom in an agriculturally-influenced Great Lakes tributary

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journal of Oceanology and Limnology 2018年第4期36卷 1112-1125页

作者： Robert Michael L.McKAY taylor TUTTLE Laura A.REITZ George S.BULLERjAHN william R.CODY Adam j.McDOwELL Timothy w.DAVIS Department of Biological Sciences Bowling Green State University Bowling Green OH 43403 USA Aquatic Taxonomy Specialists Malinta OH 43535 USA City of Defiance Water Division Defiance OH 43512 USA NOAA Great Lakes Environmental Research Laboratory Ann Arbor MI USA

In late May 2016, a cyanobacterial harmful algal bloom(cHAB) was detected in the Maumee River, the largest tributary to Lake Erie, the southernmost lake of the Laurentian Great Lakes system. Testing on 31 May identified Planktothrix agardhii as the dominant cyanobacterium with cell abundance exceeding 1.7×10~9 cells/L and total microcystins(MC) reaching 19 μg/L MC-LR equivalents, a level over 10-fold higher than the 2015 revised U.S. Environmental Protection Agency(EPA) national health advisory levels for drinking water exposure to adults. Low river discharge coincident with negligible precipitation through the latter half of May coincided with an 80% decline in river turbidity that likely favored bloom formation by a low-light adapted P. agardhii population. Also contributing to the c HAB were high initial nutrient loads and an increase of the river temperature from 13℃ to 26℃ over this same period. The bloom persisted through 5 june with microcystins exceeding 22 μg/L MC-LR equivalents at the bloom peak. By 6 june, the river had returned to its muddy character following a rain event and sampling on 7 june detected only low levels of toxin(water systems located near the bloom origin. The elevated toxin production associated with this early onset bloom was without precedent for the Maumee River and an unique attribute of the c HAB was the high proportion of potentially-toxic genotypes. whereas Planktothrix spp. is common in lotic environments, and has been previously detected in the Maumee, blooms are not commonly reported. This early onset, microcystin-producing c HAB provided a rare opportunity to glean insights into environmental factors that promote bloom development and dominance by Planktothrix in lotic environments.

关键词：伊利湖蓝藻生态系统生物学

Update of transmission modelling and projections of gambiense human African trypanosomiasis in the Mandoul focus, Chad

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Infectious Diseases of Poverty 2022年第1期11卷 34-46页

作者： Kat S.Rock Ching-I Huang Ronald E.Crump paul R.Bessell paul E.Brown Inaki Tirados Philippe Solano Marina Antillon Albert Picado Severin Mbainda justin Darnas Emily H.Crowley Steve j.Torr Mallaye Peka Mathematics Institute University of WarwickAcademic Loop RoadCoventryCV47ALUK Zeeman Institute for Systems Biology&Infectious Disease Epidemiology Research(SBIDER) University of WarwickAcademic Loop RoadCoventryCV47ALUK Independent Consultant EdinburghUK Department of Vector Biology Liverpool School of Tropical MedicineLiverpoolUK Institut de Recherche pour le Développement UMR INTERTRYP IRD-CIRADUniversitéde Montpellier34398MontpellierFrance Swiss Tropical and Public Health Institute BaselSwitzerland University of Basel BaselSwitzerland Foundation for Innovative New Diagnostics(FIND) GenevaSwitzerland Programme National de Lutte contre la Trypanosomiase Humaine Africaine(PNLTHA) MoundouChad

Background:In recent years,a programme of vector control,screening and treatment of gambiense human African trypanosomiasis(gHAT)infections led to a rapid decline in cases in the Mandoul focus of *** represent the biology of transmission between humans and tsetse,we previously developed a mechanistic transmission model,fitted to data between 2000 and 2013 which suggested that transmission was interrupted by *** present study outlines refinements to the model to:(1)Assess whether elimination of transmission has already been achieved despite low-level case reporting;(2)quantify the role of intensified interventions in transmission reduction;and(3)predict the trajectory of gHAT in Mandoul for the next decade under different ***:Our previous gHAT transmission model for Mandoul was updated using human case data(2000-2019)and a series of model *** include how diagnostic specificity is incorporated into the model and improvements to the fitting method(increased variance in observed case reporting and how underreporting and improvements to passive screening are captured).A side-by-side comparison of fitting to case data was performed between the ***:we estimated that passive detection rates have increased due to improvements in diagnostic availability in fixed health facilities since 2015,by 2.1-fold for stage 1 detection,and 1.5-fold for stage *** find that whilst the diagnostic algorithm for active screening is estimated to be highly specific(95%credible interval(CI):99.9-100%,Specificity=99.9%),the high screening and low infection levels mean that some recently reported cases with no parasitological confirmation might be false *** also find that the focus-wide tsetse reduction estimated through model fitting(95%CI:96.1-99.6%,Reduction=99.1%)is comparable to the reduction previously measured by the decline in tsetse catches from monitoring *** line with previous results,the model suggests that transmission was

关键词： Gambiense human African trypanosomiasis (gHAT) Modelling Elimination of transmission Validation Tsetse Vector control Glossina Diagnostics

Stem cell therapy for the treatment of Leydig cell dysfunction in primary hypogonadism

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world journal of Stem Cells 2016年第10期8卷 306-315页

作者： taylor C Peak Nora M Haney william wang Kenneth j DeLay wayne j Hellstrom Department of Urology School of MedicineTulane University

The production of testosterone occurs within the Leydig cells of the testes. when production fails at this level from either congenital, acquired, or systemic disorders,the result is primary hypogonadism. while numerous testosterone formulations have been developed, none are yet fully capable of replicating the physiological patterns of testosterone secretion. Multiple stem cell therapies to restore androgenic function of the testes are under investigation. Leydig cells derived from bone marrow, adipose tissue, umbilical cord, and the testes have shown promise for future therapy for primary hypogonadism. In particular, the discovery and utilization of a group of progenitor stem cells within the testes, known as stem Leydig cells(SLCs), has led not only to a better understanding of testicular development, but of treatment as well. when combining this with an understanding of the mechanisms that lead to Leydig cell dysfunction, researchers and physicians will be able to develop stem cell therapies that target the specific step in the steroidogenic process that is deficient. The current preclinical studies highlight the complex nature of regenerating this steroidogenic process and the problems remain unresolved. In summary, there appears to be two current directions for stem cell therapy in male primary hypogonadism. The first method involves differentiating adult Leydig cells from stem cells of various origins from bone marrow, adipose, or embryonic sources. The second method involves isolating, identifying, and transplanting stem Leydig cells into testicular tissue. Theoretically, in-vivo re-activation of SLCs in men with primary hypogonadism due to age would be another alternative method to treat hypogonadism while eliminating the need for transplantation.

关键词： Stem cell therapy Leydig cells Primary hypogonadism Stem Leydig cells Testosterone Bone marrow-derived stem cells Adipose-derived mesenchymal stem cells

Influences of Biochar and Biochar-Mineral Complex on Mycorrhizal Colonisation and Nutrition of wheat and Sorghum

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Pedosphere 2015年第5期25卷 686-695页

作者： paul BLACKwELL Stephen jOSEPH paul MUNROE Hossain M.ANAwAR paul STORER Robert j.GILKES Zakaria M.SOLAIMAN Department of Agriculture and Food western Australia Geraldton Regional Office School of Materials Science and Engineering University of New South WalesSydney Discipline of Chemistry University of Newcastle University of wollongong School of Earth and Environment and UwA Institute of Agriculture The University of Western Australia Australian Mineral Fertilisers Pty Ltd. Soil Biology and Molecular Ecology Group School of Earth and Environment and UWA Institute of AgricultureThe University of Western Australia

The high price of synthetic fertilisers and the price barrier for biochar as a soil amendment have encouraged the exploration of using biochar in fertiliser replacement formulations. Biochars coupled with fertilisers can be applied at lower application rates to achieve benefits in plant growth and nutrition, as well as soil biological fertility. It is necessary to evaluate the use of biochar as a fertiliser substitute. Therefore, this study investigated the comparative influences of biochars, including Acacia saligna(AS), Simcoa jarrah(Sj) and wundowie jarrah(wj), mineral fertiliser with microbes(MF + M), biochar-mineral complex(BMC) and their combination on mycorrhizal colonisation, growth and nutrition of wheat in a glasshouse experiment and sorghum in field conditions. BMC + MF +M treatment produced higher mycorrhizal colonisation than MF + M alone, indicating that BMC had a significant role in increasing mycorrhizal colonisation. Sj(treated with acetic acid) and MF + M treatments, as well as AS + MF + M application, showed similar effects on mycorrhizal colonisation, but lower colonisation than the BMC + MF + M treatment. Overall, the BMC + MF + M treatment supported the maximum shoot, root and total plant dry weight followed by AS + MF + M and wj + MF + M. The MF+ M treatment had the maximum shoot N and K concentrations, while BMC + MF + M application had the maximum shoot P concentration. AS + MF + M and wj + MF + M treatments supported the maximum N uptake by wheat shoots, while BMC + MF+ M supported the maximum P uptake. The results showed that biochars and BMCs could increase mycorrhizal colonisation, plant growth and nutrient uptake of wheat, particularly N, P, K, S and Zn. The field experiment confirmed that BMC application at a rate of 300 kg ha-1could increase the yield of irrigated sorghum on a loam soil and provide better applied P use efficiency compared to a water-soluble fertiliser alone. These results indicated that biochar-based fertilisers might

关键词：生物矿物小麦生长生物炭菌根营养高粱复合物可持续发展能力

Experimental Observation of Bright and Dark Solitons Mode-Locked with Zirconia-Based Erbium-Doped Fiber Laser

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Chinese Physics Letters 2018年第2期35卷 25-28页

作者： A.M.Markom S.j.Tan H.Haris M.C.paul A.Dhar S.Das S.w.Harun Faculty of Electrical Engineering Universiti Teknologi MARAMasai 81750Malaysia School of Engineering KDU University CollegeUtropolis GlenmarieShah Alam 40150Malaysia Department of Electrical Engineering University of MalayaKuala Lumpur 50603Malaysia Fiber Optics and Photonics Division CSIR-Central Glass and Ceramic Research InstituteKolkata 700032India

we demonstrate the generation of dark and bright solitons with our homemade zirconia-based erbium-doped fiber and graphene oxide（GO） saturable absorber in anomalous dispersion *** GO is fabricated using an abridged Hummer＇s method,which is combined with polyethylene oxide to produce a composite *** film is sandwiched between two optical ferrules and embedded in the laser cavity to enhance its birefringence and *** self-starting bright soliton is easily generated at pump power of 78 mw with the whole length cavity of 14.7 *** laser produces the bright pulse train with repetition rate,pulse width,pulse energy and central wavelength being 13.9 MHz,0.6 ps,2.74 p j and 1577.46 nm,***,by adding the 10 m of single mode fiber into the laser cavity,dark soliton pulse is *** the formation of dark pulse train,the measured repetition rate,pulse width,pulse energy and central wavelength are 8.3 MHz,20 ns and 4.98 p j and1596.82 nm,*** pulses operate in the anomalous region.

关键词： Zr EDF Experimental Observation of Bright and Dark Solitons Mode-Locked with Zirconia-Based Erbium-Doped Fiber Laser

The role of exosomes in peripheral nerve regeneration

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Neural Regeneration Research 2015年第5期10卷 743-747页

作者： Rosanna C.Ching paul j.Kingham Department of Integrative Medical Biology Umea University Department of Surgical & Perioperative Sciences Umea University

Peripheral nerve injuries remain problematic to treat, with poor functional recovery commonly observed. Injuries resulting in a nerve gap create specific difficulties for axonal regeneration. Approaches to address these difficulties include autologous nerve grafts （which are currently the gold standard treatment） and synthetic conduits, with the latter option being able to be im- pregnated with Schwann cells or stem cells which provide an appropriate micro-environment for neuronal regeneration to occur. Transplanting stem cells, however, infers additional risk of malignant transformation as well as manufacturing difficulties and ethical concerns, and the use of autologous nerve grafts and Schwann ceils requires the sacrifice of a functioning nerve. A new approach utilizing exosomes, secreted extracellular vesicles, could avoid these complications. In this review, we summarize the current literature on exosomes, and suggest how they could help to improve axonal regeneration following peripheral nerve injury.

关键词： axonal regeneration exosome extracellular vesicle microRNA microvesicle nerve gap neurite outgrowth peripheral nerve injury Schwann cell stem cell

Uncovering the genetic diversity of Giardia intestinalis in isolates from outbreaks in New Zealand

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Infectious Diseases of Poverty 2022年第3期11卷 27-36页

作者： paul Ogbuigwe Patrick j.Biggs juan Carlos Garcia-Ramirez Matthew A.Knox Anthony Pita Niluka Velathanthiri Nigel P.French David T.S.Hayman School of Veterinary Science Massey UniversityPalmerston NorthManawatu-WanganuiNew Zealand School of Natural Sciences Massey UniversityPalmerston NorthManawatu-WanganuiNew Zealand

Background:Giardia intestinalis is one of the most common causes of diarrhoea worldwide. Molecular techniques have greatly improved our understanding of the taxonomy and epidemiology of this parasite. Co-infection with mixed (sub-) assemblages has been reported, however, Sanger sequencing is sometimes unable to identify shared subtypes between samples involved in the same epidemiologically linked event, due to samples showing multiple dominant subtypes within the same outbreak. Here, we aimed to use a metabarcoding approach to uncover the genetic diversity within samples from sporadic and outbreak cases of giardiasis to characterise the subtype diversity, and determine if there are common sequences shared by epidemiologically linked cases that are missed by Sanger ***:we built a database with 1109 unique glutamate dehydrogenase (gdh) locus sequences covering most of the assemblages of G. intestinalis and used gdh metabarcoding to analyse 16 samples from sporadic and outbreak cases of giardiasis that occurred in New Zealand between 2010 and ***:There is considerable diversity of subtypes of G. intestinalis present in each sample. The utilisation of metabarcoding enabled the identification of shared subtypes between samples from the same outbreak. Multiple variants were identified in 13 of 16 samples, with Assemblage B variants most common, and Assemblages E and A present in mixed ***:This study showed that G. intestinalis infections in humans are frequently mixed, with multiple subtypes present in each host. Shared sequences among epidemiologically linked cases not identified through Sanger sequencing were detected. Considering the variation in symptoms observed in cases of giardiasis, and the potential link between symptoms and (sub-) assemblages, the frequency of mixed infections could have implications for our understanding of host–pathogen interactions.

关键词： DNA sequencing Epidemiology Genetic diversity Giardiasis Metabarcoding

Feasibility, acceptability, and effectiveness of non-pharmaceutical interventions against infectious diseases among crisis-affected populations: a scoping review

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Infectious Diseases of Poverty 2022年第1期11卷 8-26页

作者： jonathan A.Polonsky Sangeeta Bhatia Keith Fraser Arran Hamlet janetta Skarp Isaac j.Stopard Stéphane Hugonnet Laurent Kaiser Christian Lengeler Karl Blanchet paul Spiegel world Health Organization GenevaSwitzerland Institute of Global Health Faculty of MedicineUniversity of GenevaGenevaSwitzerland MRC Centre for Global Infectious Disease Analysis Department of Infectious Disease EpidemiologyImperial College LondonLondonUK Abdul Latif jameel Institute for Disease and Emergency Analytics Imperial College LondonLondonUK Swiss Tropical and Public Health Institute BaselSwitzerland University of Basel BaselSwitzerland Geneva Centre of Humanitarian Studies University of GenevaGenevaSwitzerland Center for Humanitarian Health Johns Hopkins Bloomberg School of Public HealthBaltimoreUSA

Background:Non-pharmaceutical interventions(NPIs)are a crucial suite of measures to prevent and control infectious disease *** being particularly important for crisis-affected populations and those living in informal settlements,who typically reside in overcrowded and resource limited settings with inadequate access to healthcare,guidance on NPI implementation rarely takes the specific needs of such populations into *** therefore conducted a systematic scoping review of the published evidence to describe the landscape of research and identify evidence gaps concerning the acceptability,feasibility,and effectiveness of NPIs among crisis-affected populations and informal ***:we systematically reviewed peer-reviewed articles published between 1970 and 2020 to collate available evidence on the feasibility,acceptability,and effectiveness of NPIs in crisis-affected populations and informal *** performed quality assessments of each study using a standardised *** analysed the data to produce descriptive summaries according to a number of categories:date of publication;geographical region of intervention;typology of crisis,shelter,modes of transmission,NPI,research design;study design;and study ***:Our review included 158 studies published in 85 peer-reviewed *** research used low quality study *** acceptability,feasibility,and effectiveness of NPIs was highly context *** general,simple and cost-effective interventions such as community-level environmental cleaning and provision of water,sanitation and hygiene services,and distribution of items for personal protection such as insecticide-treated nets,were both highly feasible and ***,financial,and human resource constraints affected both the implementation and sustainability of *** engagement emerged as a strong factor contributing to the effectiveness of ***,measures that involve po

关键词： Disease outbreaks Communicable disease control Prevention & control Vulnerable populations warfare and armed conflicts Disasters Relief work Poverty areas

Species Concepts as Applied to the whitefly Bemisia tabaci Systematics:How Many Species Are There?

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journal of Integrative Agriculture 2012年第2期11卷 176-186页

作者： LIU Shu-sheng john Colvin paul j De Barro Key Laboratory of Agricultural Entomology Ministry of Agriculture~Institute of lnsect Sciences Zhejiang University Hangzhou 310058 P.R. China Natural Resources Institute University of Greenwich Kent ME4 4TB United Kingdom CSIRO Ecosystem Sciences Brisbane QLD 4001 Australia

The worldwide distribution and extensive genetic diversity of the whitefly,Bemisia tabaci,has long been ***,the levels of separation within *** and the nomenclature of the various genetic groups have been a subject of *** phylogenetic analyses indicate that *** is a complex composed of 28 morphologically indistinguishable *** this article,we first review the debate and difficulties associated with ***＇s taxonomy and systematics,and argue for the need to apply the biological species concept in order to elucidate ***＇s *** summarize the accumulated genetic and behavioural data on reproductive incompatibilities evident amongst phylogenetic mtCOI groups of *** studies have been conducted with 14 of the 28 putative species covering 54 reciprocal inter-species pairs,and observations on mating behaviour have been conducted for seven species *** from both crossing trials and behavioural observations indicate a consistent pattern of reproductive isolation among the putative *** then discuss the technical and conceptual complexities associated with crossing experiments and behavioural observations designed to reveal reproductive ***,we elaborate on a strategy for further clarifying the pattern of reproductive isolation between *** groups and propose future research directions on the systematics of this complex.

关键词： whitefly systematics biological species cryptic species phylogenetic species reproductive isolation mating behavior taxonomy