scholarly journals Bait-attending amphipods of the Tonga Trench and depth-stratified population structure in the scavenging amphipod Hirondellea dubia Dahl, 1959

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e5994 ◽  
Author(s):  
James P.A. Wilson ◽  
Kareen E. Schnabel ◽  
Ashley A. Rowden ◽  
Rachael A. Peart ◽  
Hiroshi Kitazato ◽  
...  
Keyword(s):  
Population Structure ◽  
Life Stage ◽  
Previous Suggestion ◽  
Bathymetric Range ◽  
Baited Traps ◽  
Shallow Site ◽  
New Hebrides ◽  
Deep Site ◽  
A Site ◽  
First Time

Background The hadal zone encompasses the deepest parts of the world’s ocean trenches from depths of ∼6,000–11,000 m. The communities observed at these depths are dominated by scavenging amphipods that rapidly intercept and consume carrion as it falls to the deepest parts of the trenches. New samples collected in the Tonga Trench provide an opportunity to compare the amphipod assemblages and the population structure of a dominant species, Hirondellea dubia Dahl, 1959, between trenches and with earlier data presented for the Tonga Trench, and other trenches in the South Pacific. Methods Over 3,600 individual scavenging amphipods across 10 species were collected in seven baited traps at two sites; in the Horizon Deep site, the deepest part of the Tonga Trench (10,800 m) and a site directly up-slope at the trench edge (6,250 m). The composition of the bait-attending amphipods is described and a morphometric analysis of H. dubia examines the bathymetric distribution of the different life stages encountered. Results The amphipod assemblage was more diverse than previously reported, seven species were recorded for the first time from the Tonga Trench. The species diversity was highest at the shallower depth, with H. dubia the only species captured at the deepest site. At the same time, the abundance of amphipods collected at 10,800 m was around sevenfold higher than at the shallower site. H. dubia showed clear ontogenetic vertical structuring, with juveniles dominant at the shallow site and adults dominant at the deep site. The amphipods of the deeper site were always larger at comparable life stage. Discussion The numbers of species encountered in the Tonga Trench is less than reported from the New Hebrides and Kermadec trenches, and six species encountered are shared across trenches. These findings support the previous suggestion that the fauna of the New Hebrides, Tonga and Kermadec Trenches may represent a single biogeographic province. The ontogenetic shift in H. dubia between the two Tonga Trench sites supports the hypothesis of interspecific competition at the shallower bathymetric range of the species, and the presence of competitive physiological advantages that allow the adults at the trench axis to exploit the more labile organic material that reaches the bottom of the trench.

scholarly journals The T788G Mutation in thecyp51CGene Confers Voriconazole Resistance in Aspergillus flavus Causing Aspergillosis

2012 ◽  
Vol 56 (5) ◽  
pp. 2598-2603 ◽  
Author(s):  
Wei Liu ◽  
Yi Sun ◽  
Wei Chen ◽  
Weixia Liu ◽  
Zhe Wan ◽  
...  
Keyword(s):  
Aspergillus Flavus ◽  
Resistant Strain ◽  
Antifungal Susceptibility ◽  
Gene Replacement ◽  
Content Type ◽  
Replacement Method ◽  
First Choice ◽  
The One ◽  
A Site ◽  
First Time

ABSTRACTWith voriconazole (VRC) being approved as the first choice in treating invasive aspergillosis (IA) and its increasing use in treatment, a VRC-resistant strain ofAspergillus flavus, the second leading cause of IA afterAspergillus fumigatus, has emerged. The VRC-resistant strain ofA. flavuswas isolated for the first time from the surgical lung specimen of an IA patient with no response to VRC therapy. In order to ascertain the mechanism of VRC resistance, the azole target enzyme genes in this strain ofA. flavuswere cloned and sequenced, and 4 mutations generating amino acid residue substitutions were found in thecyp51Cgene. To further determine the role of this mutated gene for VRC resistance inA. flavus, anAgrobacterium tumefaciens-mediated gene replacement approach was applied. Consequently, the mutatedcyp51Cgene from thisA. flavusstrain was proven to confer the VRC resistance. Finally, to discern the one out of the four mutations in thecyp51Cgene that is responsible for contributing to VRC resistance, a site-directed gene mutagenesis procedure combined with a gene replacement method was performed. As a result, the T788G missense mutation in thecyp51Cgene was identified as responsible for VRC resistance inA. flavus. These findings indicated that the detection of this mutation inA. flavuscould serve as an indicator for physicians to avoid the use of VRC during IA treatment. Further comprehensive surveillance for antifungal susceptibility, as well as intensive study on the mechanism of azole resistance inA. flavuscausing IA, would be required to fully understand this mechanism.

scholarly journals Gravidographics: A Health Lifestyle Segmentation of Pregnant Women in Transition to First Time Motherhood

2021 ◽  
Author(s):  
◽  
Jayne Krisjanous
Keyword(s):  
Pregnant Women ◽  
Health Behaviour ◽  
Survey Design ◽  
Life Stage ◽  
Cross Sectional ◽  
Main Research ◽  
Health Lifestyle ◽  
Novel Approach ◽  
First Time ◽  
The Way

<p>The purpose of this thesis is to contribute a new health psychographic/ lifestyle segmentation of pregnant women in New Zealand who are in transition to first time motherhood. It provides a better understanding of the make up of the market and the way it aggregates into health lifestyle segments. By using a wide selection of pre-existing and pregnancy related health and attitude dimensions, it complements existing understanding and classifications of pregnancy health lifestyle. First, the study richly describes pregnancy health behaviour within a representative cohort of pregnant women in a transitional lifestyle using a holistic framework. It takes into account lifestyle as made up of a combination of factors and underlying motivations. Furthermore, it establishes the application of 'lifestyle' as it is used in marketing as legitimate for the study of a transitional health lifestyle. The research is cross disciplinary, and for that reason, integrates two perhaps seemingly disparate (marketing and health) understandings of lifestyle, using a somewhat novel approach. It is inclusive of high risk pregnant women and a much less oft studied group, normal, healthy or low risk women. Second, a key component of this study is the seminal development of a segmentation typology that classifies women's health in pregnancy through a situation specific psychographic approach. This typology has been termed 'Gravidographics', and identifies segments of pregnant women, who have distinct or unique identifiers in regard to their pregnancy health lifestyle. This knowledge will be useful for health behaviour change through social marketing and also the design and targeting of products and services to specific groups of pregnant consumers. A third focus of the study is the examination of health lifestyle within the concept of life stage transition. As pregnancy marks the transit into a new life stage, there are many adaptations that need to be made, and several underlying factors influence the way such a journey is approached and achieved. The study is exploratory and the conceptual framework, derived predominantly from the marketing and health literature, guides the study and informs development of the data collection tools. Eight main research questions are explored. The study uses a survey design and is cross sectional, with quantitative enquiry the dominant logic. A survey using a self administered health psychographic questionnaire was distributed by Lead Maternity Carers to pregnant women in their care. A sample of 478 women was obtained for this stage of the study. Quantitative analysis was undertaken through descriptive statistics and bi-variate analyses. Secondly, two step clustering was undertaken to develop pregnancy health lifestyle clusters. Four health lifestyle segments were identified. These segments were then profiled against additional variables and data that led to rich descriptions of each segment. Several managerial recommendations are made that will assist in the delivery and positioning of maternity health goods and services particularly in regard to healthcare marketing and segmentation. Secondly, recommendations for future marketing communication strategies targeting pregnant women are made. Through this work, the study's ultimate aim; making an academic contribution to knowledge that will lead to improved health outcomes for mother and baby, has been achieved.</p>

scholarly journals Seed Mediated Synthesis of Colloidal Halide Perovskite Nanoplatelets

2021 ◽  
Author(s):  
C. Meric Guvenc ◽  
sinan balci
Keyword(s):  
Optical Properties ◽  
Halide Salt ◽  
Seed Solution ◽  
Synthesis Route ◽  
Line Widths ◽  
Halide Perovskite ◽  
Seed Mediated ◽  
A Site ◽  
First Time ◽  
Lead Halide

<p><b>Two-dimensional lead halide perovskite nanoplatelets (2D LHP NPLs) have been emerging as one of the most promising semiconductor nanomaterials due to their narrow absorption and emission line widths, tunable bandgaps, high exciton binding energies, high defect tolerance as well as highly localized energy states. Colloidal synthesis of 2D LHP NPLs is generally performed using hot-injection or ligand assisted precipitation techniques (LARP). In the LARP method, perovskites are synthesized in polar solvents, which decrease the stability of the 2D LHP NPLs due to their weakly bonded nature. In fact, the presence of residual polar solvent in the LHP NPL colloid can cause deterioration of thickness uniformity, degradation of NPLs to parent precursors, and undesired phase transformations. Herein, for the first time, we report facile seed-mediated synthesis route of monolayer, 2-monolayers, and thicker lead halide perovskite nanoplatelets without using A site cation halide salt (AX</b><b>;</b><b> A = Cesium, methylammonium, formamidinium and, X = Cl, Br, I) and long chain alkylammonium halide salts (LX; L = oleylammonium, octylammonium, butylammonium and, X = Cl, Br, I). The seed solution has been synthesized by reacting lead (II) halide salt and coordinating ligands (oleylamine or octylamine and oleic acid) in nonpolar high boiling solvent (1-octadecene). The seed mediated synthesis has been carried out in hexane by reacting seed solution with A-site cation precursors (Cs-oleate, FA-oleate, or diluted MA solution in hexane) under ambient conditions. More importantly, the seed mediated growth of NPLs has been tracked for the first time by performing in-situ optical measurements. Furthermore, the optical properties and morphologies of the seeds have been extensively studied. We find that our facile synthesis route provides highly stable, monodisperse NPLs with narrow absorption, and photoluminescence line widths (68-201 meV), and high PLQY (37.6-1.66% for 2ML NPLs). Furthermore, anion exchange reactions have been performed by mixing pre-synthesized LHP NPLs with counter halide seeds. The optical properties of NPLs have been affectively tuned by postsynthetic chemical reactions without changing the thickness of the NPLs. We anticipate that our new synthetic route provides further understanding of growth dynamics of LHP NPLs.</b></p>

The Palace of the Republic versus the Stadtschloss: The Dilemmas of Planning in the Heart of Berlin

2003 ◽  
Vol 21 (4) ◽  
pp. 30-73 ◽  
Author(s):  
Susanne Ledanff
Keyword(s):  
Architectural Design ◽  
Capital City ◽  
Holocaust Memorial ◽  
The Republic ◽  
German Bundestag ◽  
Historical Sites ◽  
Architectural Competitions ◽  
A Site ◽  
Art And Architecture ◽  
First Time

On 4 July 2002, the German Bundestag had to decide on the futureof one of the capital city’s principal historical sites: the square knownas the Schlossplatz, where the Hohenzollern Palace once stood butthat since 1976 had been the site of the German Democratic Republic’sflagship Palace of the Republic. It was not the first time thatGerman politicians had been called upon to decide issues relating toart and architecture. On previous occasions votes had been taken onthe wrapping of the Reichstag by Christo and Jeanne-Claude, SirNorman Foster’s dome, Hans Haacke’s artistic installation “DerBevölkerung” inside the Reichstag, and Peter Eisenman’s design forBerlin’s Holocaust memorial.1 Their decision to rebuild the historicalpalace, however, differed in that the politicians did not vote onan architectural design, “in eigener Sache.”2 That is, it was not abuilding or monument belonging to the governmental or politicalsphere of the capital city but rather a site likely to house culturalinstitutions. Parliamentarians, thus, were called upon to settle atwelve-year-old planning and architectural controversy after all othermeans, including architectural competitions, had failed.

Biological Sampling and Analysis Procedures for the United Nations Special Commission (UNSCOM) in Iraq

1995 ◽  
Vol 14 (2) ◽  
pp. 240-243 ◽  
Author(s):  
Alan J. Mohr
Keyword(s):  
United Nations ◽  
Environmental Samples ◽  
Biological Research ◽  
Special Commission ◽  
Biological Sampling ◽  
The United Nations ◽  
June July ◽  
A Site ◽  
First Time ◽  
Production Facilities

In June/July 1994, I was fortunate in having been selected by the United Nations Special Commission (UNSCOM) to be the chief inspector (CI) of one of the most interesting inspections conducted by the commission, namely UNSCOM 84/BW6. This particular inspection was fascinating because of its complexity—the team not only conducted inspections of Iraqi biological research and production facilities, it also excavated a site that UNSCOM surmised might contain materials from Iraq's former BW program. As such, this inspection was the first time that UNSCOM collected environmental samples for analysis. In this paper I discuss my experiences during this inspection and comment on the effectiveness of sampling and analysis as a verification measure.

scholarly journals A relict population of Cymbalophora rivularis on the Pollino Massif, southern Italy (Lepidoptera: Erebidae)

2018 ◽  
pp. 37-41
Author(s):  
Silvia Greco ◽  
Francesco Luigi Leonetti ◽  
Stefano Scalercio
Keyword(s):  
Plant Species ◽  
National Park ◽  
Southern Italy ◽  
First Record ◽  
South Italy ◽  
Refuge Area ◽  
Relict Populations ◽  
Relict Population ◽  
A Site ◽  
First Time

The first record for South Italy of Cymbalophora rivularis (Ménétriès, 1832) is reported, until now recorded in Italy only for Central Apennine. Three specimens were collected during August-September 2017, in an Acer spp. forest located on Monte Sparviere, a Site of Community Importance within the Pollino National Park. Furthermore, this species was successfully barcoded for the first time. This finding reinforces the biogeographic importance of Pollino Massif as refuge area for relict populations of several animal and plant species.

Evaluation of an in situ early life stage test with cutthroat trout, Oncorhynchus clarki, for environmental monitoring – a case study using mine effluent

2013 ◽  
Vol 49 (2) ◽  
pp. 95-103 ◽  
Author(s):  
B. Chalmers ◽  
J. Elphick ◽  
G. Gilron ◽  
H. Bailey
Keyword(s):  
Early Life ◽  
Life Stage ◽  
Cutthroat Trout ◽  
Early Life Stage ◽  
Exposure Period ◽  
Low Flow ◽  
Treated Effluent ◽  
Mine Effluent ◽  
A Site

This study evaluated an in situ early life stage test using cutthroat trout for potential use in Canada's Metal Mines Effluent Regulations' Environmental Effects Monitoring (EEM) program. Current field monitoring approaches focus on either adult fish surveys or mesocosm studies, but both of these have inherent limitations that may affect their suitability on a site-specific basis. This study evaluated an alternative approach, namely an in situ toxicity test, as part of an EEM program for a zinc, copper and gold mine. Hatchboxes containing cutthroat trout embryos were placed in a creek that receives treated effluent from the mine, and monitored through the swim-up stage to evaluate hatching success, survival, normal development and growth. Advantages of the method include: no feeding requirement during exposure, fixed exposure locations, relevant endpoints and high statistical sensitivity. In addition, the extended exposure period integrated long-term exposure variables, including low-flow and freshet events. This approach also has application to other salmonid species and types of discharges.

The Rabbit in Subalpine South-eastern Australia. I. Population Structure and Productivity

1974 ◽  
Vol 1 (1) ◽  
pp. 1 ◽  
Author(s):  
DJ Dunsmore
Keyword(s):  
Population Structure ◽  
National Park ◽  
Initial Level ◽  
Adult Survival ◽  
South Eastern ◽  
Breeding Group ◽  
Eastern Australia ◽  
Domestic Livestock ◽  
A Site ◽  
Better Than

An unconfined, almost completely tagged rabbit population on a site of about 100 ha was studied by observation and trapping for 5 years. The commencement of the study coincided approximately with the incorporation of the area into the Kosciusko National Park, the elimination of grazing by domestic livestock, and the cessation of the previously almost annual burning of the area. During the 5-yr study the fecundity of the rabbits declined to little more than half the initial level. This was not a result of the concurrently increasing age of the population, which was shown to be quite unrelated. It was also shown that the 1yr old rabbits were less fecund than the older rabbits, whose fecundity remained constant. Although it appeared subjectively to be so, the area was not uniformly suitable for the survival of rabbits. In one of its four subdivisions adult survival was much better than in the others; and in one of the others it was much the worst. During the study there was considerable immigration to the area, presumably balanced by migration. Females tended to remain where they were born and in no case changed from one breeding group to another. Males were considerably less sedentary than the females.

scholarly journals Effects of anoxia and sulfide on concentrations of total and methyl mercury in sediment and water in two Hg-polluted lakes

2001 ◽  
Vol 58 (3) ◽  
pp. 506-517
Author(s):  
Olof Regnell ◽  
Tommy Hammar ◽  
Anders Helgée ◽  
Bo Troedsson
Keyword(s):  
Surface Sediment ◽  
Methyl Mercury ◽  
Manganese Oxides ◽  
Cellulose Fiber ◽  
Concomitant Decrease ◽  
Shallow Site ◽  
Fe And Mn ◽  
Total Hg ◽  
Deep Site

Between May and December 1996, monthly samples of surface sediment (0–1 cm), settling matter, and water were taken at a shallow site and a deep site in each of two consecutive Hg-polluted riverine lakes. In the upper lake, the sediment was polluted also with cellulose fiber. Both hypolimnia turned anoxic, but sulfide was detected only in the upper lake. When sulfide appeared, hypolimnetic methyl mercury (MeHg) increased and reached 47 pM (9.4 ng·L–1), whereas MeHg in the sediment below decreased. The increase in hypolimnetic inorganic Hg (IHg = total Hg – MeHg), which reached a peak of 40 pM (8.0 ng·L–1), was slower, possibly because mobilized IHg was methylated. In the lower lake, hypolimnetic MeHg and IHg increased less dramatically during summer stratification, reaching only 5 and 24 pM (1.0 and 4.8 ng·L–1), respectively. There was no detectable concomitant decrease in sediment MeHg. In both lakes, MeHg appeared to increase simultaneously with total Fe and Mn in the hypolimnion, as did IHg in the lower lake. Our observations suggest that the presence of hydrous ferric and manganese oxides decreased the mobility of Hg in both lakes but increased MeHg production in the upper lake.

The non-homogeneous Markov system in a stochastic environment

1993 ◽  
Vol 30 (02) ◽  
pp. 285-301 ◽  
Author(s):  
N. Tsantas ◽  
P.-C. G. Vassiliou
Keyword(s):  
Population Structure ◽  
Stochastic Environment ◽  
Input Process ◽  
Relative State ◽  
Markov System ◽  
Basic Parameters ◽  
Manpower System ◽  
Relative Structure ◽  
First Time

We introduce and define for the first time the concept of a non-homogeneous Markov system in a stochastic environment (S-NHMS). The problem of finding the expected population structure in an S-NHMS is studied, and important properties among the basic parameters of the S-NHMS are established. Moreover, we study the problem of maintaining the relative sizes of the states in a stochastic environment applying control in the input process. Among other things, we provide the probability of maintaining any vector of relative state sizes. Also strategies for attaining in an optimal way a desired relative structure are designed, with the use of a given algorithm. Finally, an illustration is provided of the present results in a manpower system.

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