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Petrogenesis of the Late Cretaceous Tholeiitic Volcanism and Oceanic Island Arc Affinity of the Chagai Arc, Western Pakistan

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Acta Geologica Sinica(English Edition) 2017年第4期91卷 1248-1263页

作者： Rehanul Haq SIddIQUI M. Qasim JAN Mohammad Asif KHAN M. Ishaq KAKAR john d. FOdEN Baluchistan University of Information Technology Engineering and Management Sciences Quetta Pakistan National Centre of Excellence in Geology University of Peshawar Peshawar & COMSTECH Islamabad Pakistan Karakoram International University Gilgit Pakistan Centre of Excellence in Mineralogy University of Baluchistan Quetta Pakistan department of Earth Sciences University of Adelaide SA 5005 Australia

The Late Cretaceous Chagai arc outcrops in western Pakistan, southern Afghanistan and eastern Iran. It is in the Tethyan convergence zone, formed by northward subduction of the Arabian oceanic plate beneath the Afghan block. The oldest unit of the Chagai arc is the Late Cretaceous Sinjrani Volcanic Group. This is composed of porphyritic lava flows and volcaniclastic rocks, and subordinate shale, sandstone, limestone and chert. The flows are fractionated low-K tholeiitic basalts, basaltic- andesites, and andesites. Relative enrichment in their LILE and depletion in HFSE, and negative Nb and Ta and positive K, Ba and Sr anomalies point to a subduction-related origin. Compared to MORB, the least fractionated Chagai basalts have low Na2O, Fe2O3^T, CaO, Ti, Zr, Y and ^87Sr/^86Sr. Rather than an Andean setting, these results suggest derivation from a highly depleted mantle in an intraoceanic arc formed by Late Cretaceous convergence in the Ceno-Tethys. The segmented subduction zone formed between Gondwana and a collage of small continental blocks （Iran, Afghan, Karakoram, Lhasa and Burma） was accompanied by a chain of oceanic island arcs and suprasubduction ophiolites including Semail, Zagros, Chagai-Raskoh, Kandahar, Muslim Bagh, Waziristan and Kohistan-Ladakh, Nidar, Nagaland and Manipur. These complexes accreted to the southern margin of Eurasia in the Late Cretaceous.

关键词： Chagai arc tholeiitic volcanics Late Cretaceous western Pakistan

A tissue-engineered rostral migratory stream for directed neuronal replacement

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Neural Regeneration Research 2018年第8期13卷 1327-1331页

作者： john C.O'donnell Kritika S.Katiyar Kate V.Panzer d.Kacy Cullen Center for Brain Injury & Repair Department of Neurosurgery Perelman School of Medicine University of Pennsylvania Center for Neurotrauma Neurodegeneration & Restoration Corporal Michael Crescenz Veterans Affairs Medical Center School of Biomedical Engineering Drexel University department of Bioengineering School of Engineering and Applied Science University of Pennsylvania

New neurons are integrated into the circuitry of the olfactory bulb throughout the lifespan in the mamma- lian brain--including in humans. These new neurons are born in the subventricular zone and subsequently mature as they are guided over long distances via the rostral migratory stream through mechanisms we are only just beginning to understand. Regeneration after brain injury is very limited, and although some neuroblasts from the rostral migratory stream will leave the path and migrate toward cortical lesion sites, this neuronal replacement is generally not sustained and therefore does not provide enough new neurons to alleviate functional deficits. Using newly discovered microtissue engineering techniques, we have built the first self-contained, implantable constructs that mimic the architecture and function of the rostral migratory stream. This engineered microtissue emulates the dense cord-like bundles of astrocytic somata and processes that are the hallmark anatomical feature of the glial tube. As such, our living microtissue-en- gineered rostral migratory stream can serve as an in vitro test bed for unlocking the secrets of neuroblast migration and maturation, and may potentially serve as a living transplantable construct derived from a patient＇s own cells that can redirect their own neuroblasts into lesion sites for sustained neuronal replace- ment following brain injury or neurodegenerative disease. In this paper, we summarize the development of fabrication methods for this microtissue-engineered rostral migratory stream and provide proof-of-princi- ple evidence that it promotes and directs migration of immature neurons.

关键词： rostral migratory stream glial tube astrocyte neuroblast brain injury neural repair neural regeneration tissue engineering

Subcutaneous fatty acid composition of steers finished as weanlings or yearlings with and without growth promotants

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Journal of Animal Science and Biotechnology 2014年第1期5卷 98-105页

作者： Cletos Mapiye Tyler d Turner john A Basarab Vern S Baron Jennifer L Aalhus Michael ER dugan Agriculture and Agri-Food Canada Lacombe Research Centre 6000 C & E Trail Lacombe Alberta T4L 1 W1 Canada Alberta Agriculture and Rural development Lacombe Research Centre 6000 C & E Trail Lacombe Alberta T4L 1 W1 Canada

Background： The current study evaluated the subcutaneous fatty acid （FA） composition of calf- and yearling-fed steer with or without growth promoting implants. Crossbred steers （n = 112; 267 ± 5.0 kg） of the same contemporary group were allocated to one of four production system and implant strategy based treatments in a completely randomized design with a 2 × 2 factorial arrangement of treatments. Results： There were no interactions （P 〉 0.05） between production systems and growth promoting implants for the total and individual subcutaneous FA. Yearling as opposed to calf finishing reduced （P 〈 0.05） subcutaneous proportions of C20：3n-6, trans （t）l 2-18：1, C14：0, several minor cis-monounsaturated FA （c-MUFA; c9-14：1, c11-16：1, cl 1-18：1, cl 2-18：1, cl 3-18：1, c9-20：1 and cl 1-20：1）, and increased （P 〈 0.05） subcutaneous proportions of tl 1 cl 5-18：2, total and individual branched-chain FA. Subcutaneous fat from steers implanted with growth promotants had higher （P 〈 0.05） proportions of total polyunsaturated FA （PUFA）, total n-6 PUFA, C18：2n-6 and individual t-18：1 isomers （t6 to tl0） compared to non-implanted steers. Conclusions： Overall, current findings show that production systems and growth promotants led to only minor differences in subcutaneous FA composition of beef steers.

关键词： Age at feedlot entry Beef Fatty acids Growth implant Steers

Bloch surface eigenstates within the radiation continuum

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Light(Science & Applications) 2013年第1期2卷 113-118页

作者： Chia Wei Hsu Bo Zhen Song-Liang Chua Steven G johnson john d Joannopoulos Marin Soljacic Research Laboratory of Electronics Massachusetts Institute of TechnologyCambridgeMA 02139USA department of Physics Harvard UniversityCambridgeMA 02138USA department of Mathematics Massachusetts Institute of TechnologyCambridgeMA 02139USA

From detailed numerical calculations,we demonstrate that in simple photonic crystal structures,a discrete number of Bloch surface-localized eigenstates can exist inside the continuum of free-space *** to the free space causes the surface modes to leak,but the forward and back-reflected leakage may interfere destructively to create a perfectly bound surface state with zero *** perform analytical temporal coupled-mode theory analysis to show the generality of such phenomenon and its robustness from variations of system ***,time-reversal invariance,two-fold rotational symmetry and a perfectly reflecting boundary are necessary for these unique states.

关键词： bound state in continuum embedded eigenvalue photonic crystal surface mode

Very Low-Level Heteroplasmy mtdNA Variations Are Inherited in Humans

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Journal of Genetics and Genomics 2013年第12期40卷 607-615页

作者： Yan Guo Chung-I Li Quanhu Sheng Jeanette F.Winther Qiuyin Cai john d.Boice Yu Shyr Vanderbilt Ingram Cancer Center Center for Quantitative Sciences department of Applied Mathematics Chiayi University (NCYU) Institute of Cancer Epidemiology Danish Cancer Society Vanderbilt Epidemiology Center Vanderbilt University School of Medicine National Council on Radiation Protection & Measurements

Little is known about the inheritance of very low heteroplasmy mitochondria dNA （mtdNA） variations. Even with the development of new next-generation sequencing methods, the practical lower limit of measured heteroplasmy is still about 1% due to the inherent noise level of the sequencing. In this study, we sequenced the mitochondrial genome of 44 individuals using Illumina high-throughput sequencing technology and obtained high-coverage mitochondria sequencing data. Our study population contains many mother-offspring pairs. This unique study design allows us to bypass the usual heteroplasmy limitation by analyzing the correlation of mutation levels at each position in the mtdNA sequence between maternally related pairs and non-related pairs. The study showed that very low heteroplasmy variants, down to almost 0.1%, are inherited maternally and that this inheritance begins to decrease at about 0.5%, cor- resnondin to abottleneck of about 200 mtdNA.

关键词： Maternal inheritance Next-generation sequencing High-depth sequencing Heteroplasmy mtdNA mutations Bottleneck

Characterization of gut microbiome and metabolome in Helicobacter pylori patients in an underprivileged community in the United States

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World Journal of Gastroenterology 2021年第33期27卷 5575-5594页

作者： Brian White john d Sterrett Zoya Grigoryan Lauren Lally Jared d Heinze Hyder Alikhan Christopher A Lowry Lark J Perez Joshua deSipio Sangita Phadtare department of Biomedical Sciences Cooper Medical School of Rowan UniversityCamdenNJ 08103United States department of Integrative Physiology University of Colorado BoulderBoulderCO 80309United States department of Internal Medicine Lenox Hill HospitalNYCNY 10075United States department of Internal Medicine Thomas Jefferson University HospitalPhiladelphiaPA 19107United States department of Biological Sciences Rowan UniversityGlassboroNJ 08028United States department of Chemistry and Biochemistry Rowan UniversityGlassboroNJ 08028United States department of Gastroenterology Cooper University HospitalCamdenNJ 08103United States

BACKGROUNd Helicobacter pylori(***),a bacterium that infects approximately half of the world’s population,is associated with various gastrointestinal diseases,including peptic ulcers,non-ulcer dyspepsia,gastric adenocarcinoma,and gastric *** the burden of antibiotic resistance increases,the need for new adjunct therapies designed to facilitate *** eradication and reduce negative distal outcomes associated with infection has become more *** of the interactions between ***,the fecal microbiome,and fecal fatty acid metabolism,as well as the mechanisms underlying these interactions,may offer new therapeutic *** To characterize the gut microbiome and metabolome in *** patients in a socioeconomically challenged and underprivileged inner-city *** Stool samples from 19 *** patients and 16 control subjects were analyzed.16S rRNA gene sequencing was performed on normalized pooled amplicons using the Illumina MiSeq System using a MiSeq reagent kit *** and beta diversity analyses were performed in QIIME ***-targeted fatty acid analysis of the samples was carried out using gas chromatography-mass spectrometry,which measures the total content of 30 fatty acids in stool after conversion into their corresponding fatty acid methyl ***-dimensional scaling(MdS)was performed on Bray-Curtis distance matrices created from both the metabolomics and microbiome datasets and a Procrustes test was performed on the metabolomics and microbiome MdS *** Fecal microbiome analysis showed that alpha diversity was lowest in *** patients over 40 years of age compared to control subjects of similar age *** diversity analysis of the samples revealed significant differences in microbial community structure between *** patients and control subjects across all ***-eight and six taxa had lower and higher relative abundance in *** patients,*** that were e

关键词： Gut microbiome Metabolome Helicobacter pylori Antibiotic resistance dysbiosis Eradication

Guild composition and habitat use of voles in 2 forest landscapes in south-eastern Norway

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Integrative Zoology 2011年第4期6卷 299-310页

作者： Lucrezia GORINI john d.C.LINNELL Luigi BOITANI Ulrike HAUPTMANN Morten OddEN Per WEGGE Erlend B.NILSEN department of Animal and Human Biology Sapienza University of RomeRomeItaly Faculty of Applied Ecology and Agricultural Sciences Hedmark University CollegeCampus EvenstadKoppangNorway Norwegian Institute for Nature Research TrondheimNorway department of Ecology and Natural Resource Management Norwegian University of Life SciencesÅsNorway

It is widely believed that intensive forestry has influenced small mammal population dynamics,and thereby the entire mammalian community in Fennoscandian boreal *** nature of these impacts on the different species is subject to *** live-trapped voles between 2006 and 2009 in 2 commercially harvested forests in south-eastern *** investigated the variation in vole abundance among habitat types(*** forest and clear-cut)and the hypothesis that graminivorous species such as field voles(Microtus agrestis L.)benefit from clear-cuts at the expense of forest dwellers(*** bank vole,Myodes glareolus Schreb.),using fine-scale descriptors of the ground *** could not find support for the hypothesis that field voles show a preference for clear-cuts,and their overall abundance was low,while bank voles were the dominant species in all habitat types,including clear-cuts in the peak and pre-peak *** found a positive association between bank vole abundance and bilberry(Vaccinium myrtillus L.)availability rather than a specific habitat *** field vole density in clear-cuts might be due to variation in local productivity and ground vegetation as well as to large variation in the species temporal *** latter is particularly associated with the widespread decline of field voles in *** has the potential to negatively affect bank vole population dynamics because of the negative effect on bilberry development.

关键词： bank vole bilberry clear-cut field vole forestry

Metabolic Engineering of Plant-derived (E)-β-farnesene Synthase Genes for a Novel Type of Aphid-resistant Genetically Modified Crop Plants

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Journal of Integrative Plant Biology 2012年第5期54卷 282-299页

作者： Xiu-dao Yu john Pickett You-Zhi Ma Toby Bruce johnathan Napier Huw d.Jones Lan-Qin Xia Institute of Crop Sciences(ICS) Chinese Academy of Agricultural Sciences(CAAS)Beijing 100081China Rothamsted Research HarpendenHertfordshire AL52JQUK

Aphids are major agricultural pests that cause significant yield losses of crop plants each year. Excessive dependence on insec- ticides for long-term aphid control is undesirable because of the development of insecticide resistance, the potential negative effects on non-target organisms and environmental pollution. Transgenic crops engineered for resistance to aphids via a non-toxic mode of action could be an efficient alternative strategy. （E）-β-Farnesene （EβF） synthases catalyze the formation of EβF, which for many pest aphids is the main component of the alarm pheromone involved in the chemical communication within these species. EβF can also be synthesized by certain plants but is then normally contaminated with inhibitory compounds. Engineering of crop plants capable ofsynthesizing and emitting EβF could cause repulsion of aphids and also the attraction of natural enemies that use EβF as a foraging cue, thus minimizing aphid infestation. In this review, the effects of aphids on host plants, plants＇ defenses against aphid herbivory and the recruitment of natural enemies for aphid control in an agricultural setting are briefly introduced. Furthermore, the plant-derived EβF synthase genes cloned to date along with their potential roles in generating novel aphid resistance via genetically modified approaches are discussed.

关键词： Aphids (E)-β-farnesene sythase genetic-modified crops terpenoid.

2d matrix based indexing with color spectralhistogram for efficient image retrieval

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Journal of Systems Engineering and Electronics 2016年第5期27卷 1122-1134页

作者： maruthamuthu ramasamy john sanjeev kumar athisayam department of Software Engineering RVS College of EngineeringDindigul 624005India department of Computer Applications Thiagarajar College of EngineeringMadurai 625015India

A novel content based image retrieval （CBIR） algorithmusing relevant feedback is presented. The proposed frameworkhas three major contributions： a novel feature descriptor calledcolor spectral histogram （CSH） to measure the similarity betweenimages; two-dimensional matrix based indexing approach proposedfor short-term learning （STL）; and long-term learning （LTL）.In general, image similarities are measured from feature representationwhich includes color quantization, texture, color, shapeand edges. However, CSH can describe the image feature onlywith the histogram. Typically the image retrieval process starts byfinding the similarity between the query image and the imagesin the database; the major computation involved here is that theselection of top ranking images requires a sorting algorithm to beemployed at least with the lower bound of O（n log n）. A 2d matrixbased indexing of images can enormously reduce the searchtime in STL. The same structure is used for LTL with an aim toreduce the amount of log to be maintained. The performance ofthe proposed framework is analyzed and compared with the existingapproaches, the quantified results indicates that the proposedfeature descriptor is more effectual than the existing feature descriptorsthat were originally developed for CBIR. In terms of STL,the proposed 2d matrix based indexing minimizes the computationeffort for retrieving similar images and for LTL, the proposed algorithmtakes minimum log information than the existing approaches.

关键词： content based image retrieval (CBIR) color spectralhistogram (CSH) short-term learning (STL) long-term learning(LTL) similarity measures.