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Matter and Radiation at Extremes 2020年第1期5卷 16-22页

作者： Joseph Nilsen Andrea L.Kritcher Madison EMartin Robert E.Tipton Heather D.Whitley damian c.swift Tilo Doppner Benjamin L.Bachmann Amy E.Lazicki Natalie B.Kostinski Brian R.Maddox Gilbert W.collins Siegfried H.Glenzer Roger W.Falcone Lawrence Livermore National Laboratory LivermoreCalifornia 94551USA University of Rochester RochesterNew York 14627USA SLAc National Accelerator Menlo ParkCalifornia 94025USA University of california Berkeley BerkeleyCalifornia 94720USA

Over the last six years many experiments have been done at the National Ignition Facility to measure the Hugoniot of materials,such ascHplastic at extreme pressures,up to 800 ***“Gbar”design employs a strong spherically converging shock launched through a solid ball of material using a hohlraum radiation *** shock front conditions are characterized using x-ray *** this paper we examine the role of radiation in heating the unshocked material in front of the shock to understand the impact it has on equation of state measurements and how it drives the measured data off the theoretical Hugoniot *** particular,the two main sources of radiation heating are the preheating of the unshocked material by the high-energy kilo-electron-volt x-rays in the hohlraum and the heating of the material in front of the shock,as the shocked material becomes hot enough to radiate *** our model,we estimate that preheating can reach 4 eV in unshocked material,and that radiation heating can begin to drive data off the Hugoniot significantly,as pressures reach above 400 Mb.

关键词： spherical equation radiative

A signal-substrate match in the substrate-borne component of a multimodal courtship display

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current Zoology 2010年第3期56卷 370-378页

作者： damian O.ELIAS Andrew c.MASON Eileen A.HEBETS Department of Environmental Science Policy and ManagementUniversity of California Integrative Behaviour and Neuroscience Group University of Toronto Scarborough School of Biological Sciences University of Nebraska

The environment can impose strong limitations on the efficacy of signal transmission. In particular, for vibratory communication, the signaling environment is often extremely heterogeneous at small scales. Nevertheless, natural selection is expected to select for signals well-suited for effective transmission. Here, we test for substrate-dependent signal efficacy in the wolf spider Schizocosa stridulans Strattou 1991. We first explore the transmission characteristics of this important signaling mo- dality by playing recorded substrate-bome signals through three different substrates （leaf litter, pine litter, and red clay） and measuring the propagated signal. We found that the substrate-bome signal of S. stridulans attenuates the least on leaf litter, the substrate upon which the species is naturally found. Next, by assessing mating success with artificially muted and non-muted males across different signaling substrates （leaf litter, pine litter, and sand）, we explored the relationship between substrate-bome signaling and signaling substrate for mating success. We found that muted males were unsuccessful in obtaining copulations re- gardless of substrate, while mating success was dependent on the signaling substrate for non-muted males. For non-muted males, more males copulated on leaf litter than any other substrate. Taken together, these results confLrm the importance of sub- strate-bome signaling in S. stridulans and suggest a match between signal properties and signal efficacy - leaf litter transmits the signal most effectively and males are most successful in obtaining copulations on leaf litter [current Zoology 56 （3）： 370-378, 2010].

关键词： Environmental heterogeneity Sensory drive Mate choice communication

can active late-type stars contribute to the Galactic lithium abundance?

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Research in Astronomy and Astrophysics 2020年第7期20卷 127-133页

作者： Darnell E.Kelly damian J.christian Mihalis Mathioudakis Darko Jevremovi′c Department of Physics and Astronomy California State UniversityNorthridgeCA 91330-8268USA Astrophysics Research centre School of Mathematics and PhysicsQueen’s University BelfastBelfast BT71NNUK Astronomical Observatory Volgina 711060 BelgradeSerbia

Lithium abundances in our Galaxy and especially 6 Li abundances provide important constraints on our understanding of Big Bang Nucleosynthesis(BBNS),stellar evolution and the creation of light elements by cosmic rays in the ISM.~6 Li has been detected in energetic solar events,one chromospherically active binary and several dwarf halo *** our work on active late-type stars with high lithium abundances,we expand our study to consider if the flare origin of lithium created by spallation can contribute significantly to the Galactic abundance of *** previously derived ~6 Li/~7 Li=0.030 ± 0.010 for active K dwarf GJ 117 using VLT UVES *** find^6 Li/~7 Li ratios of 0.02 and 0.10 for two other stars in our sample,GJ 182 and EUVE J1145-55.3 A,*** that these later type,active stars have significant flare rates and stellar winds,we have estimated the contribution of these stars to the Galactic lithium *** that K and M stars comprise over 84% of our Galaxy and that many of these can have significant stellar winds,we conclude that spallation in stellar flares can contribute 1% and up to 5% of the Galactic lithium abundance.

关键词： stars:abundances stars:activity Galaxy:abundances

Photo enhanced degradation of contaminants of emerging concern in waste water

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Emerging contaminants 2020年第1期6卷 283-302页

作者： Olalekan c.Olatunde Alex T.Kuvarega damian c.Onwudiwe Material Science Innovation and Modelling(MaSIM)Research Focus Area Faculty of Natural and Agricultural SciencesNorth-West UniversityMafikeng CampusPrivate Bag X2046Mmabatho2735South Africa Department of chemistry School of Physical and Chemical SciencesFaculty of Natural and Agricultural SciencesNorth-West UniversityMafikeng CampusPrivate Bag X2046Mmabatho2735South Africa Nanotechnology and Water Sustainability Research Unit College of ScienceEngineering and TechnologyUniversity of South AfricaFlorida1709South Africa

Emerging contaminants are posing serious global threats to the environment due to their diversity,recalcitrant nature and *** disturbing is the fact that current wastewater treatment systems do not have the capacity to deal with these class of *** quest to develop new technologies to mitigate the adverse effects of these contaminants has engendered new research interest on photo-enhanced ***-enhanced processes,with the potential of mineralizing environmental pollutants,currently appears to be the main viable technology for dealing with emerging *** process of contaminant degradation could either proceed via oxidation or reduction routes,referred to as advanced oxidation processes(AOPs)and advanced reduction processes(ARPs)***,different processes have been incorporated into a single system in order to explore the synergy that ensue from the combination of these *** processes that are currently at the front line in dealing with various classes of emerging contaminants,whose presence in the environment continues to grow on a daily basis,are the focus of this review.

关键词： Photocatalysis Advanced oxidation processes Advanced reduction process Emerging contaminants Mineralization Waste water

Analysis of the lifetime and culling reasons for AI boars

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Journal of Animal Science and Biotechnology 2017年第4期8卷 866-874页

作者： damian Knecht Anna Jankowska-Maosa Kamil Duziński Institute of Animal Breeding Wroclaw University of Environmental and Life SciencesChelmonskiego 38C51–630 WroclawPoland

Background: The aim of the study was to analyze the lifetime and culling reasons for boars used in insemination centers(AI centers).Methods: The data collected from 355 culled boars from 1998 to 2013 included: age at start of semen collection,boar herd life, culling reason, daily gain and lean meat content, and number of ejaculates not meeting sales requirements after dilution. culling reasons were divided into 7 groups: low semen value(LSV), low or lack of libido(LL), leg problems(LP), infectious diseases(ID), old age(OA), reduced demand for semen from the given boar(RD),and others(OT).Results: The most common culling reasons for boars were LSV(23.7%) and RD(22.5%). It was observed that the lowest daily gains were noted in boars culled due to OA. Boars culled due to OA and RD were maintained in production for the longest time(over 1000 d), for LSV and ID retention was about 700 d, and due to LL below 400 d. The survival probability was over 0.9 until 1.5 yr, and just over 0.2 until 4 yr. The highest relative frequency was observed in the 36 ^(th) and 42 ^(nd) mo of life(over 16%). Hazard risk analysis revealed a more than 10 times higher risk of culling in the case of LL, ID or OT, in comparison to ***: The results can be used as a direct point of reference for the identification of emerging problems in AI boar exploitation and the development of an appropriate culling policy in AI centers.

关键词： AI centers Boars culling Exploitation Management

Origins of the supercontinent cycle

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Geoscience Frontiers 2013年第4期4卷 439-448页

作者： R.damian Nance J.Brendan Murphy Department of Geological Sciences.316 Clippinger Laboratories.Ohio University.Athens.OH 45701.USA Department of Earth Sciences st.Francis Xavier UniversityAntigonishNova Scotia B2G 2W5.Canada

The supercontinent cycle, by which Earth history is seen as having been punctuated by the episodic assembly and breakup of supercontinents, has influenced the rock record more than any other geologic phenomena, and its recognition is arguably the most important advance in Earth Science since plate tectonics. It documents fundamental aspects of the planet＇s interior dynamics and has charted the course of Earth＇s tectonic, climatic and biogeochemical evolution for billions of years. But while the widespread realization of the importance of supercontinents in Earth history is a relatively recent development, the supercontinent cycle was first proposed thirty years ago and episodicity in tectonic processes was recognized long before plate tectonics provided a potential explanation for its occurrence. With interest in the supercontinent cycle gaining momentum and the literature expanding rapidly, it is instructive to recall the historical context from which the concept developed. Here we examine the supercontinent cycle from this perspective by tracing its development from the early recognition of long-term epi- sodicity in tectonic processes, through the identification of tectonic cycles following the advent of plate tectonics, to the first realization that these phenomena were the manifestation of episodic superconti- nent assembly and breakup.

关键词： Supercontinent cyclePlate tectonicsTectonic episodicitySecular trends

cane toads beneath bird rookeries： utilization of a natural disturbance by an invasive species

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current Zoology 2018年第4期64卷 433-439页

作者： damian c. LETTOOF Jessica A. LYONS Richard SHINE Grdgoire MANIEL Martin MAYER Daniel J, D.NATUScHa School of Life and Environmental Sciences University of Sydney NSW 2006 Australia Resource Evaluation and Development Bamaga QLD 4876 Australia 87 cours Aristide Briand 33000 Bordeaux France Faculty of Arts and Sciences University College of Southeast Norway Bei Telemark Norway

Many invasive species exploit anthropogenically disturbed habitats, but most of those taxa evolved long before humans. Presumably, then, an ability to use natural （non-anthropogenic） disturbances pre-adapted invaders to a world later degraded by people. Studies on invasive species in naturally disturbed habitats thus can clarify the ancestral niche of invaders. In the Australian tropics, metallic starlings Aplonis metallica nest communally in emergent rainforest trees during the wet-season, and invasive cane toads Rhinella marina join other predators （mammals, birds, reptiles, and other anurans） to exploit the food resources beneath those trees. compared to conspecifics found along nearby roads through the forest, cane toads beneath bird-nesting trees occur at higher densities, and are smaller in body size. The sex ratio is female-biased, and recapture records suggest that fe- males may be philopatric at these sites （whereas recaptures were rare for both sexes found along the roads）. Some toads were found under the same trees in successive wet-seasons. Spooling showed that distances moved per night were similar along the road versus under the trees, but toads under trees showed lower net displacements. Diets also differed （based upon scat analysis）, with tree toads feeding more on beetles and less on ants. These nutrient-rich hotspots are ex- ploited primarily by adult females and juvenile toads, whereas adult males congregate at breeding sites. By magnifying pre-existing intraspecific divergences in habitat use, bird rookeries may en- hance population viability of cane toads by enabling critical age and sex classes to exploit food- rich patches that are rarely used by adult males.

关键词： ancestral niche communal nesting niche partitioning pre-adaptation spatial ecology

Monitoring nonlinear and fast deformation caused byunderground mining exploitation using multi-temporal Sentinel-1 radar interferometry and corner reflectors: application,validation and processing obstacles

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International Journal of Digital Earth 2023年第1期16卷 251-271页

作者： Kamila Pawłuszek-Filipiak Natalia Wielgocka damian Tondaś Andrzej Borkowski Institute of Geodesy and Geoinformatics Wroclaw University of Environmental and Life SciencesWroclawPoland

In this study,Differential Interferometric Synthetic Aperture Radar Interferometry(DInSAR)of artificial corner Reflectors(cRs)were validated in the area of fast and nonlinear deformation gradient caused by active coal longwall *** Sentinel-1 datasets were processed using conventional DInSAR,Persistent Scatterer Interferometry(PSI),and Small BAseline Subset methods implemented in ENVI SARscape™.For evaluation,leveling and Global Navigation Satellite System(GNSS)measurements were *** the challenge of snow cover,the removal of all winter images was not a successful strategy due to the long temporal baseline and strong movement,which cause phase unwrapping problems and underestimate the real *** results indicate that only conventional DInSAR and SBAS with low network redundancy allow us to capture maximal deformation gradient and the root mean square error calculated between the cRs and the ground truth is on the level of 2–3 cm for the vertical and easting deformation component,*** the small deformation gradient represented by the permanent GNSS station(4 cm/year),all SBAS techniques appeared to be more accurate than DInSAR,which corresponds to higher redundancy and better removal of the atmospheric *** contrast,DInSAR results allowed to capture information about two subsidence basins,which was not possible with SBAS and PSI approaches.

关键词： DInSAR PSI SBAS corner reflectors mining deformations nonlinear and significantdeformation phase unwrapping errors

MicroRNA profile in neosquamous esophageal mucosa following ablation of Barrett's esophagus

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World Journal of Gastroenterology 2017年第30期23卷 5508-5518页

作者： Loveena Sreedharan George c Mayne David I Watson Timothy Bright Reginald V Lord Alfiya Ansar Tingting Wang Jakob Kist David StJ Astill damian J Hussey Department of Surgery Flinders Medical Centre Flinders University St Vincent’s centre for Applied Medical Research Department of Anatomical Pathology Flinders Medical Centre

To investigate the microRNA expression profile in esophageal neosquamous epithelium from patients who had undergone ablation of Barrett’s esophagus. METHODSHigh throughput screening using TaqMan® Array Human MicroRNA quantitative PcR was used to determine expression levels of 754 microRNAs in distal esophageal mucosa (1 cm above the gastro-esophageal junction) from 16 patients who had undergone ablation of non-dysplastic Barrett’s esophagus using argon plasma coagulation vs pretreatment mucosa, post-treatment proximal normal non-treated esophageal mucosa, and esophageal mucosal biopsies from 10 controls without Barrett’s esophagus. Biopsies of squamous mucosa were also taken from 5 cm above the pre-ablation squamo-columnar junction. Predicted mRNA target pathway analysis was used to investigate the functional involvement of differentially expressed microRNAs. RESULTSForty-four microRNAs were differentially expressed between control squamous mucosa vs post-ablation neosquamous mucosa. Nineteen microRNAs were differentially expressed between post-ablation neosquamous and post-ablation squamous mucosa obtained from the more proximal non-treated esophageal segment. Twelve microRNAs were differentially expressed in both neosquamous vs matched proximal squamous mucosa and neosquamous vs squamous mucosa from healthy patients. Nine microRNAs (miR-424-5p, miR-127-3p, miR-98-5p, miR-187-3p, miR-495-3p, miR-34c-5p, miR-223-5p, miR-539-5p, miR-376a-3p, miR-409-3p) were expressed at higher levels in post-ablation neosquamous mucosa than in matched proximal squamous and healthy squamous mucosa. These microRNAs were also more highly expressed in Barrett’s esophagus mucosa than matched proximal squamous and squamous mucosa from controls. Target prediction and pathway analysis suggests that these microRNAs may be involved in the regulation of cell survival signalling pathways. Three microRNAs (miR-187-3p, miR-135b-5p and miR-31-5p) were expressed at higher levels in post-

关键词： Neosquamous Barrett’s esophagus Ablation

A comparative Study of Antioxidant Activities between Fresh and Dry Mushrooms in the Genera <i>cantharellus</i>and <i>Afrocantharellus</i>from Tanzania

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Food and Nutrition Sciences 2014年第2期5卷 212-221页

作者： Donatha damian Tibuhwa Department of Molecular Biology and Biotechnology (MBB) University of Dar es Salaam Dar es Salaam Tanzania.

cantharellus and Afrocantharellus mushrooms are widely consumed in both fresh and dry forms. However, their antioxidant and whether their values changing with drying processes are not known. This study establishes their values and the effect of sun drying on their quality and quantity. Methanolic extracts of five cantharellus and two Afrocantharellus species were investigated. The investigation used (1,1-diphenyl-2-picrylhydrazyl radical) DPPH as a substrate to determine radical scavenging abilities. Further quantitative analyses for carotenoids, flavonoid, total phenolic compounds and vitamin c content were done using spectrophotometric assay at 515 nm. comparatively, fresh mushroom had higher vitamin c and Lycopene contents than their dry counterparts with β-carotene. Flavonoid and phenolic compounds were higher in dry forms than those in their fresh counterparts. Radical scavenging ability also varied with fresh forms depicting higher activity compared to dry forms. The variation was low in Afrocantharellus species (0.8% and 0.99%) while it was higher in cantharellus species (24.12% and 7.52%). The highest ability was observed in fresh forms of cantharellus pseudocibarius (Ec50 50 = 0.4 mg/ml) was from dry form of cantharellus rufopunctatus. This shows that studied mushrooms are rich in antioxidants and their quality and quantities are affected differently in both forms. Both dry and fresh mushrooms are potential sources of natural antioxidants. The portrayed high scavenging ability by these mushrooms envisages promoting them into potential nutraceutics.

关键词： Antioxidant Activity Fresh Mushrooms Sun-Dried Mushrooms Afrocantharellus cantharellus 1 1-Diphenyl-2-picrylhydrazyl