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The effects of tannins-containing ground pine bark diet upon nutrient digestion,nitrogen balance,and mineral retention in meat goats

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Journal of Animal Science and Biotechnology 2015年第3期6卷 347-354页

作者： Byeng Ryel Min Sandra Solaiman thomas Terrill Aina Ramsay Irene Mueller-harvey Department of Agricultural and Environmental Sciences Tuskegee University Agricultural Research Station Fort-Valley State University School of Agriculture Policy and DevelopmentUniversity of Reading

Background： Pine bark is a rich source of phytochemical compounds including tannins, phenolic acids, anthocyanins, and fatty acids. These phytochemicals have potential to significantly impact on animal health and animal production. The goal of this work is to measure the effects of tannins in ground pine bark as a partial feed replacement on feed intake, dietary apparent digestibility, nitrogen balance, and mineral retention in meat goats. Results： Eighteen Kiko cross goats （initial BW = 31.8 ± 1.49 kg） were randomly assigned to three treatment groups （n = 6）. Dietary treatments were tested： control （0 % pine bark powder （PB） and 30 % wheat straw （WS））; ] 5 % PB and 15 % WS, and 30 % PB and 0 % WS. Although dry matter （DM） intake and digestibility were not affected （P〉 0.10） by feeding PB, neutral detergent fiber （linear; P= 0.01）, acid detergent fiber （linear; P= 0.001） and lignin digestibility （linear; P= 0.01） decreased, and crude protein （CP） digestibility tended to decrease （P=0.09） as PB increased in the diet, apparent retention of Ca （P= 0.09）, P （P=0.03）, Mg （P= 0.01）, Mn （P= 0.01）, Zn （P= 0.01） and Fe （P= 0.09） also increased linearly. Nitrogen intake and fecal N excretion were not affected （P〉 0.05） by addition of PB in the diet, but N balance in the body was quadratically increased （P〈 0.01） in the 15 % PB diet compared to other diets. This may be due to more rumen escape protein and less excreted N in the urine with the 15 % PB diet. The study showed that a moderate level of tannin-containing pine bark supplementation could improve gastrointestinal nitrogen balance with the aim of improving animal performance. Conclusion： These results suggest that tannin-containing PB has negative impact on fiber, lignin, and protein digestibility, but positively impacted on N-balance.

关键词： Digestibility Goats Phytochemicals Tannins

Differentiation and functional connectivity of fetal tectal transplants

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Neural Regeneration Research 2023年第11期18卷 2325-2331页

作者： Alan R.harvey School of Human Sciences The University of Western AustraliaLions Eye Instituteand Perron Institute for Neurological and Translational ScienceNedlandsWAAustralia

Data from studies analyzing the differentiation and functional connectivity of embryo nic neural tissue grafted into the mammalian nervous system has led to the clinical testing of the fetal graft approach in patients with neurodegenerative *** some success has been achieved,ethical concerns have led to a search for alternative therapeutic strategies,mostly exploring the use of neural precursors or neurons derived from pluripotent stem cells to replace damaged host neurons and restore lost *** more recent studies address questions of graft viability,differentiation,and connectivity similar to those posed by researchers in earlier fetal transplant work,thus reviews of the fetal graft literature may inform and help guide ongoing research in the stem cell/organoid *** brief review describes some key observations from research into the transplantation of neural tissue into the rat visual syste m,focusing on grafts of the fetal supe rior colliculus(tectal grafts) into neonatal or adult *** neonate hosts,grafts quickly develop connections with the underlying host mid b rain and attain a morphology typical of mature grafts by about 2 weeks.G rafts consistently contain numerous localized regions which,based on neurofibrillar staining,neuronal morphology(Golgi),neurochemistry,receptor expression,and glial architecture,are homologous to the stratum griseum supe rficiale of normal superior *** localized "patches" are also seen after explant culture and when donor tectal tissue is dissociated and reaggregated prior to *** almost all circumstances,host retinal innervation is restricted to these localized patches,but only those that are located adjacent to the graft surfa *** are formed and there is evidence of functional *** only exception occurs when Schwann cells are added to dissociated tecta prior to *** these co-grafts,the peripheral glia appear to compete with local target fa ctors a

关键词： axon regeneration differentiation embyronic grafts fetal tissue neural precursors retinotectal stem cells superior colliculus synaptogenesis transplantation

Structural and Mechanistic Aspects of Mn-oxo and Co-based Compounds in Water Oxidation Catalysis and Potential Applications in Solar Fuel Production

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Journal of Integrative Plant Biology 2010年第8期52卷 704-711页

作者： harvey J.M.Hou Department of Chemistry and Biochemistry University of Massachusetts Dartmouth North Dartmouth

To address the issues of energy crisis and global warming, novel renewable carbon-free or carbon-neutral energy sources must be identified and developed. A deeper understanding of photosynthesis is the key to provide a solid foundation to facilitate this transformation. To mimic the water oxidation of photosystem II oxygen evolving complex, Mn-oxo complexes and Co-phosphate catalytic material were discovered in solar energy storage. Building on these discoveries, recent advances in solar energy conversion showed a compelling working principle by combing the active Mn-oxo and Co-based catalysts in water splitting with semiconductor heteronanostructures for effective solar energy harnessing. In this review the appealing systems including Mn-oxo tetramer/Nafion, Mn-oxo dimer/TiO2, Mn-oxo oligomer/WO3, Co-Pi/Fe2O3, and Co-Pi/ZnO are summarized and discussed. These accomplishments offer a promising framework and have a profound impact in the field of solar fuel production.

关键词： Mn Structural and Mechanistic Aspects of Mn-oxo and Co-based Compounds in Water Oxidation Catalysis and Potential Applications in Solar Fuel Production II Figure

Silicification in Mississippian Lodgepole Formation,Northeastern Flank of Williston Basin,Manitoba,Canada

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Journal of Earth Science 2012年第1期23卷 1-18页

作者： harvey R Young Moe Kuroda Department of Geology Brandon University

Five types of replacement silica are recognized in the Lower Mississippian Virden Member carbonates on the northeastern flank of Williston basin： microcrystalline quartz, chalcedonic quartz, anhedral megaquartz, euhedral megaquartz, and stringy megaquartz. Silica tends to replace various bioclasts, and all except the stringy megaquartz also occur as non-replacive void-filling cement or as silica forming chert nodules and silicified limestone. Although crinoids, brachiopods, corals, bryozoans, molluscs, trilobites, forams, and ostracodes are present in the sediments studied, only the first three show evidence of silicification. Crinoids are commonly replaced by microcrystalline quartz whereas brachiopods typically by spherules of length slow chalcedony. Coalesced spherules, often in concentric rings （beekite rings）, may form sheet-like masses on the surface of corals and brachiopods. Although bryozoans are common in the Virden Member, none showed any evidence of silicification. The difference in the susceptibility to silicification may be related to the shell microstructure, biological group, size of organism, skeletal mineralogy, and organic content of the bioclasts. Biogenic silica derived from the dissolution of siliceous sponge spicules is considered to be the most likely silica source for silicification. Most silica is believed to be released during early diagenesis before the sediments were deeply buried. The Virden Member carbonate may have experienced two episodes of replacement, the first affecting the bioclasts, the second producing silicified limestone and chert nodules.

关键词： silicification Williston basin Lodgepole Formation Virden Member Mississippian carbonate.

Effect of host-cocoon mass on adult size in the secondary hyperparasitoid wasp, Pteromalus semotus （Hymenoptera： Pteromalidae）

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Insect Science 2012年第3期19卷 383-390页

作者： Jeffrey A. harvey Alex Gumovsky Rieta Gols Netherlands Institute of Ecology Department of Terrestrial Ecology Wageningen The Netherlands Schmalhausen Institute of Zoology Kiev Ukraine Laboratory of Entomology Plant Science Group Wageningen University Wageningen The Netherlands

Parasitoids have long proven to be model organisms in studying resourcerelated constraints on immature development. Here we examine the relationship between host cocoon （= pupal） size in the gregarious endoparasitoid wasp, Cotesia glomerata, and development time and adult size in the solitary idiobiont hyperparasitoid, Pteromalus semotus. Little is known about the biology or ecology of this ecto-hyperparasitoid species, although it is one of the major secondary hyperparasitoids of C. glomerata. The size of the adult wasp covaried with the size of the host cocoon at parasitism. Moreover, female wasps were larger than male wasps for a given cocoon size. Adult wasps have remarkably long life-spans, 3 months on average. Longevity did not significantly differ with sex. We also examined how larvae of P. semotus exclude other potential competitors. P. semotus is protandrous, with females taking significantly longer to complete their development than males. In experiments where several eggs of P. semotus were placed on individual pupae of C. glomerata, newly hatched hyperparasitoid larvae moved rapidly over the surface of the host and destroyed the eggs of any conspecifics by biting them before they would initiate feeding on host tissues. Our results are discussed in relation to those with other studies with solitary ichneumonid idiobiont hyperparasitoids of C. glomerata.

关键词： Cotesia glomerata growth idiobiont longevity protandry trade-off

Subwavelength thick ultrahigh-Q terahertz disc microresonators

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Photonics Research 2020年第7期8卷 1183-1188页

作者： Dominik Walter Vogt Angus harvey Jones thomas Alan Haase Rainer Leonhardt Department of Physics The University of AucklandAuckland 1010New Zealand The Dodd-Walls Centre for Photonic and Quantum Technologies Dunedin 9016New Zealand

Artificial structures that exhibit narrow resonance features are key to a myriad of scientific advances and *** particular,exploration of the terahertz(THz)spectrum—the final frontier of the electromagnetic spectrum—would greatly benefit from high-quality resonant *** we present a new paradigm of terahertz silicon disc microresonators with subwavelength *** results utilizing continuouswave THz spectroscopy establish quality factors in excess of 120,000 at 0.6 *** of the disc thickness to a fraction of the wavelength reduces the losses from the silicon substrate and paves the way to unparalleled possibilities for light–matter interaction in the THz frequency range.

关键词： spectrum utilizing frontier

An efficient method for unfolding kinetic pressure driven VISAR data

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High Power Laser Science and Engineering 2015年第3期3卷 50-58页

作者： M.Hess K.Peterson A.harvey-Thompson Sandia National Laboratories

Velocity Interferometer System for Any Reflector(VISAR) [Barker and Hollenbach, J. Appl. Phys. 43, 4669(1972)]is a well-known diagnostic that is employed on many shock physics and pulsed-power experiments. With the VISAR diagnostic, the velocity on the surface of any metal flyer can be found. For most experiments employing VISAR, either a kinetic pressure [Grady, Mech. Mater. 29, 181(1998)] or a magnetic pressure [Lemke et al., Intl J. Impact Eng. 38,480(2011)] drives the motion of the flyer. Moreover, reliable prediction of the time-dependent pressure is often a critical component to understanding the physics of these experiments. Although VISAR can provide a precise measurement of a flyer's surface velocity, the real challenge of this diagnostic implementation is using this velocity to unfold the timedependent pressure. The purpose of this paper is to elucidate a new method for quickly and reliably unfolding VISAR data.

关键词： laser driven blast wave pulsed-power VISAR

Human epidermal growth factor receptor targeted inhibitors for the treatment of ovarian cancer

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Cancer Biology & Medicine 2018年第4期15卷 375-388页

作者： Maria Bonello ANDrew harvey Sims Simon Peter Langdon Cancer Research UK Edinburgh Center and Division of Pathology Laboratory MRC Institute of Genetics and Molecular Medicine University of Edinburgh

Ovarian cancer is the second most lethal gynecological cancer worldwide and while most patients respond to initial therapy, they often relapse with resistant disease. Human epidermal growth factor receptors(especially HER1/EGFR and HER2/ERBB2) are involved in disease progression; hence, strategies to inhibit their action could prove advantageous in ovarian cancer patients,especially in patients resistant to first line therapy. Monoclonal antibodies and tyrosine kinase inhibitors are two classes of drugs that act on these receptors. They have demonstrated valuable antitumor activity in multiple cancers and their possible use in ovarian cancer continues to be studied. In this review, we discuss the human epidermal growth factor receptor family; review emerging clinical studies on monoclonal antibodies and tyrosine kinase inhibitors targeting these receptors in ovarian cancer patients; and propose future research possibilities in this area.

关键词： Tyrosine kinase monoclonal antibodies ovarian cancer inhibitors HER receptors

Origin of tendon stem cells in situ

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Frontiers in Biology 2018年第4期13卷 263-276页

作者： Tyler harvey Chen-Ming Fan Department of Embryology Carnegie Institution for Science Baltimore MD 21218 USA Department of Biology The Johns Hopkins University Baltimore MD 21218 USA

BACKGROUND： Adult stem cells are surveillance repositories capable of supplying a renewable source of progenitors for tissue repair and regeneration to maintain tissue homeostasis throughout life. Many tissue-resident stem cells have been identified in situ, which lays the foundation for studying them in their native microenvironment, i.e. the niche. Within the musculoskeletal system, muscle stem cells have been unequivocally identified in the mouse, which have led to considerable advances in understanding their role in muscle homeostasis and regeneration. On the other hand, for bone and tendon progenitor cells, mesenchymal stem cells have been used as the main in vitro cell model as they can differentiate into osteogenic, chondrogenic and tenogenic fates. Despite considerable efforts and employment of modern tools, the in vivo origins of bone and tendon stem cells remain debated. Tendon regeneration via stem cells is understudied and deserves attention as tendon damage is noted for a bleak, time-consuming recovery and the repaired tendon seldom regains the structural integrity and strength of the native, uninjured state. OBJECTIVE： Here we review the past efforts and recent studies toward defining adult tendon stem cells and understanding tendon regeneration instead of tendon development. The focus is on adult tendon resident cells in situ and the uncertainty of their roles in regeneration. METHODS： A systematic literature search using the Pubmed search engine was conducted encompassing the seminal papers in the tendon field. CONCLUSIONS： Investigation of tendon stem cells in situ is in its infancy mainly due to lack of necessary tools and standardized injury model. We propose a concerted effort toward establishing a comprehensive cell atlas of the tendon, making genetic tools and choosing a reliable injury model for coordinated studies among different laboratories. Increasing our basic understanding should aid future therapeutic innovations to shorten and enhance

关键词： Tendon stem cells midsubstance sheath injury