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Response of endemic afroalpine rodents to the removal of livestock grazing pressure

Current Zoology 2011年第6期57卷 741-750页

作者： Flavie VIAL David w. MACDONALD daniel T. HAYDON Boyd Orr Centre for Population and Ecosystem Health Institute of Biodiversity Animal Health and Comparative Medicine College of Medical Veterinary and Life Sciences University of Glasgow Glasgow G12 8QQ UK. wildlife Conservation Research Unit Zoology Department University of Oxford The Recanati-Kaplan Centre Tubney House Tubney OX13 5QL UK.

The Bale Mountains of Ethiopia represent the world＇s largest continuous extent of afroalpine habitat. with a peak combined density of over 8000 individuals/km2, the endemic giant mole rat Tachyoryctes macrocephalus, Blick＇s grass rat Arvi- canthis blicki and the brush-furred mouse Lophuromys melanonyx are the dominant wild herbivores within this ecosystem and may be affected by the presence of high densities of domestic livestock. The purpose of this study was to establish whether these endemic rodent populations could respond to the removal of grazing pressure inside three 0.25 hectare livestock exclosures （paired with grazed control plots） and to determine whether such response was mediated through concomitant changes in the vegetation structure. we hypothesised that livestock grazing negatively affects endemic rodent populations through competition or increased predation risk and we predicted an increase in rodent biomass following the removal of grazing pressure. we found no evidence of rodent populations responding to the removal of livestock after fourteen months. The short-term nature of the ex- perimental design, environmental fluctuations and the ecosystem＇s inherent stochasticity may explain the apparent lack of a sig- nificant response. However, while this study is inconclusive, it emphasises the need for more long-term experimental investiga- tions to assess the effects of domestic grazers on vegetation and on dependent communities. The effects of rapidly increasing livestock numbers in the Bale Mountains will require continued close monitoring of vegetation and endemic animal communities as the afroalpine is altered by external biotic and abiotic forces .

关键词： Afroalpine Bale Mountains Exclosures Livestock grazing Murid rodents

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Minimal observability of Boolean networks

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science China(Information sciences) 2022年第5期65卷 157-168页

作者： Yang LIU Jie ZHONG daniel w.C.HO weihua GUI College of Mathematics and Computer science Zhejiang Normal University Department of Mathematics City University of Hong Kong school of Information science and Engineering Central South University

In this study, the minimum observability of Boolean networks(BNs) is investigated by using the semi-tensor product(sTP) of matrices. First, a new system based on the considered BN is obtained to analyze states pair dynamic trajectories, from which a necessary and sufficient condition for the observability of BNs is determined. second, adding a new observer improves the observability without affecting the observable states. Thus, an algorithm is presented to design an observer for an unobservable BN. In addition, a necessary condition is obtained to determine the minimum number of nodes required to be directly measurable. Further,an algorithm to address the minimal observability is presented. Finally, examples are provided to demonstrate the effectiveness of the obtained results.

关键词： Boolean networks minimal observability semi-tensor product

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Dredging effects on selected nutrient concentrations and ecoenzymatic activity in two drainage ditch sediments in the lower Mississippi River Valley

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International soil and water Conservation Research 2017年第3期5卷 190-195页

作者： Matt Moore Martin A.Locke Michael Jenkins Robert w.steinriede daniel s.McChesney UsDA-Agricultural Research service National Sedimentation Laboratory598 McElroy DriveOxfordMS 38655USA

Agricultural drainage ditches are conduits between production acreage and receiving aquatic *** overlooked for their mitigation capabilities,agricultural drainage ditches provide an important role for nutrient transformation via microbial *** in ecoenzyme activities have been used to elucidate microbial metabolism and resource demand of microbial communities to better understand the relationship between altered nutrient ratios and microbial activity in aquatic *** agricultural drainage ditches,one in the northeast portion of the Arkansas Delta and the other in the lower Mississippi Delta,were monitored for a *** samples were collected prior to each ditch being dredged(cleaned),and subsequent post-dredging samples occurred as soon as access was *** samples were then collected throughout a year to examine effects of dredging on selected nutrient concentrations and ecoenzymatic activity recovery in drainage ditch *** concentrations in sediments after dredging decreased 33–66%,depending on ditch and phosphorus extraction ***,ecoenzymatic activity was significantly decreased in most sediment samples after *** diacetate hydrolysis activity,an estimate of total microbial activity,decreased 56–67%after dredging in one of the two *** sample sites also had significant phosphorus and ecoenzymatic activity differences between the post-dredge samples and the year-long follow-up *** indicate microbial metabolism in dredged drainage ditches may take up to a year or more to recover to pre-dredged ***,while sediment nutrient concentrations may be decreased through dredging and removal,runoff and erosion events over time tend to quickly replenish nutrient concentrations in replaced *** nutrient dynamics and microbial metabolism within agricultural drainage ditches is a crucial step toward addressing issues of nutri

关键词： Phosphorus FDA Denitrification Mehlich III Microbial Metabolism

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CD28 costimulation promotes an antitumor CD8^(+) T cell response in myeloid antigen-presenting cell niches

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Cellular & Molecular Immunology 2022年第2期19卷 147-149页

作者： Jacques A.Nunès daniel Olive Team Immunity and Cancer Centre de Recherche en Cancérologie de Marseille(CRCM)InsermU1068CNRSUMR7258Institut Paoli-CalmettesAix-Marseille UniversityUM 105MarseilleFrance IBisA Immunomonitoring Platform CRCMInstitut Paoli-CalmettesMarseilleFrance

Ectopic lymphoid structures found within the tumor stroma,such as tertiary lymphoid structures(TLss),are predictive markers of immune checkpoint blockade(ICB)in solid *** a recent study in Cancer Cell,Duraiswamy et *** other immune structures,such as myeloid antigen-presenting cell(APC)niches,in the context of high-grade serous ovarian cancers(HGsOCs)[1].In these structures,programmed cell death receptor 1(PD-1)^(+)tumor-infiltrating T lymphocytes(TILs)undergo a full activation program(a license to kill)via the CD28 costimulatory molecule during PD-1 blockade in HGsOC.

关键词： stimulation myeloid al.

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stabilization-based soil remediation should consider longterm challenges

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Frontiers of Environmental science & Engineering 2018年第2期12卷 1-3页

作者： Zhengtao shen Zhen Li daniel s. Alessi Department of Earth and Atmospheric sciences University of Alberta Edmonton AB T6G 2E3 Canada College of Resources and Environmental sciences Nanjing Agricultural University Nanjing 210095 China

soil remediation is of increasing importance globally, especially in developing countries. Among available remediation options, stabilization, which aims to immobilize contaminants within soil, has considerable advantages, including that it is cost-effective, versatile, sustainable, rapid, and often results in less secondary pollution. However, there are emerging challenges regard- ing the long-term performance of the technology, which may be affected by a range of environmental factors. These challenges stem from a research gap regarding the development of accurate, quantitative laboratory simula- tions of long-term conditions, whereby laboratory accel- erated aging methods could be normalized to real field conditions. Therefore, field trials coupled with long-term monitoring are critical to further verify conditions under which stabilization is effective. sustainability is also an important factor affecting the long-term stability of site remediation. It is hence important to consider these challenges to develop an optimized application of stabilization technology in soil remediation.

关键词： stabilization soil remediation Long-term,Trace metals

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Occurrence of D-amino acids in natural products

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Natural Products and Bioprospecting 2023年第1期13卷 181-205页

作者： daniel w.Armstrong Alain Berthod Department of Chemistry and Biochemistry University of Texas at ArlingtonArlingtonTX 76019USA Institut des sciences Analytiques CNRSUniversity of Lyon 169100 VilleurbanneFrance

since the identified standard genetic code contains 61 triplet codons of three bases for the 20 L-proteinogenic amino acids(AAs),no D-AA should be found in natural *** is not what is observed in the living world.D-AAs are found in numerous natural compounds produced by bacteria,algae,fungi,or marine animals,and even vertebrates.A review of the literature indicated the existence of at least 132 peptide natural compounds in which D-AAs are an essential part of their *** compounds are listed,numbered and described *** two biosynthetic routes leading to the presence of D-AA in natural products are:non-ribosomal peptide synthesis(NRPs),and ribosomally synthesized and post-translationally modified peptide(RiPP)synthesis which are *** methods used to identify the AA chirality within naturally occurring peptides are briefly *** biological activity of an all-L synthetic peptide is most often completely different from that of the D-containing natural *** the selected natural compounds showed that D-Ala,D-Val,D-Leu and D-ser are the most commonly encountered D-AAs closely followed by the non-proteinogenic D-allo-Thr.D-Lys and D-Met were the least prevalent D-AAs in natu-rally occurring compounds.

关键词： D-amino acid Chirality Biogenesis Natural products

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On the origin of plasticity-induced microstructure change under sliding contacts

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Friction 2023年第3期11卷 473-488页

作者： Yilun XU daniel s.BALINT Christian GREINER daniele DINI Department of Mechanical Engineering Imperial College LondonLondon SW72AZUK Department of Materials Imperial College LondonLondon SW72AZUK Karlsruhe Institute of Technology(KIT) Institue for Applied Materials(IAM)Kaisertrasse 12Karlsruhe 76131Germany KITIAM-CMs MicroTribology Center(μTC) Strasse am Forum 5Karlsruhe 76131Germany

Discrete dislocation plasticity(DDP)calculations are carried out to investigate the response of a single crystal contacted by a rigid sinusoidal asperity under sliding loading conditions to look for causes of microstructure change in the dislocation *** mechanistic driver is identified as the development of lattice rotations and stored energy in the subsurface,which can be quantitatively correlated to recent tribological experimental *** of surface slip initiation and substrate permanent deformation obtained from DDP calculations for varying contact size and normal load suggest ways of optimally tailoring the interface and microstructural material properties for various frictional loads.

关键词： discrete dislocation plasticity sliding size effect microstructure change

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Bone lesions in recurrent glucagonoma: A case report and review of literature

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world Journal of Gastrointestinal Oncology 2012年第6期4卷 152-155页

作者： Cristian Ghetie daniel Cornfeld Vassilios s Ramfidis Kostas N syrigos Muhammad w saif Danbury Hospital Danbury CT 06810 United States Department of Diagnostic Radiology Yale School of Medicine New Haven CT 06510 United States Third Department of Medicine Sotiria General Hospital Athens Medical School Athens 11527 Greece section of Medical Oncology Yale School of Medicine New Haven CT 06510 United States Division of Hematology and Oncology Department of Medicine Columbia University NY 10032 United States

Glucagonomas are rare neuroendocrine tumors that arise from cells of the pancreatic islets. Most of them are malignant and usually present as metastatic disease. sites most commonly involved in metastases are the liver and regional lymph nodes. Bone metastases are rare events and only a few cases have been reported in the literature. we present the case of a 53-year-old male with a medical history of recurrent non-functioning glucagonoma. He presented 17 years after the initial diagnosis with new blastic bone lesions involving the T1 vertebra and the sacrum. Diagnostic steps and medical management in metastatic glucagonoma are also reviewed.

关键词： Glucagonoma Bone metastases Blastic lesion Octreoscan

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Twisted fiber microfluidics:a cutting-edge approach to 3D spiral devices

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Microsystems & Nanoengineering 2024年第1期10卷 193-202页

作者： shunsuke Kato daniel w.Carlson Amy Q.shen Yuanyuan Guo Department of Electrical Information and Physics EngineeringSchool of EngineeringTohoku UniversityAoba-kuSendai 980-8579 MiyagiJapan Micro/Bio/Nanofluidics Unit Okinawa Institute of Science and TechnologyOnnaKunigami-gun 904-0495 OkinawaJapan Frontier Research Institute for Interdisciplinary sciences(FRIs) Tohoku UniversityAoba-kuSendai 980-0845 MiyagiJapan Graduate school of Biomedical Engineering Tohoku UniversityAoba-kuSendai 980-8579 MiyagiJapan Department of Physiology Graduate School of MedicineTohoku UniversityAoba-kuSendai 980-8575 MiyagiJapan

The development of 3D spiral microfluidics has opened new avenues for leveraging inertial focusing to analyze small fluid volumes,thereby advancing research across chemical,physical,and biological *** traditional straight microchannels rely solely on inertial lift forces,the novel spiral geometry generates Dean drag forces,eliminating the necessity for external fields in fluid ***,fabricating 3D spiral microfluidics remains a labor-intensive and costly endeavor,hindering its widespread ***,conventional lithographic methods primarily yield 2D planar devices,thereby limiting the selection of materials and geometrical *** address these challenges,this work introduces a streamlined fabrication method for 3D spiral microfluidic devices,employing rotational force within a miniaturized thermal drawing process,termed as *** innovation allows for rapid prototyping of twisted fiber-based microfluidics featuring versatility in material selection and heightened geometric *** validate the performance of these devices,we combined computational modeling with microtomographic particle image velocimetry(uTPiM)to comprehensively characterize the 3D flow *** results corroborate the presence of a steady secondary flow,underscoring the effectiveness of our *** 3D spiral microfluidics platform paves the way for exploring intricate microflow dynamics,with promising applications in areas such as drug delivery,diagnostics,and lab-on-a-chip systems.

关键词： thereby straight twisted

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Localization optoacoustic tomography

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Light(science & Applications) 2018年第1期7卷 1058-1062页

作者： X Luís Dean-Ben daniel Razansky Institute for Biological and Medical Imaging Helmholtz Center MunichNeuherberg 85764Germany school of Medicine and school of Bioengineering Technical University of MunichMunich 81675Germany

Localization-based imaging has revolutionized fluorescence optical microscopy and has also enabled unprecedented ultrasound images of microvascular structures in deep ***,we introduce a new concept of localization optoacoustic tomography(LOT)that employs rapid sequential acquisition of three-dimensional optoacoustic images from flowing absorbing *** show that the new method enables breaking through the spatial resolution barrier of acoustic diffraction while further enhancing the visibility of structures under limited-view tomographic *** the intrinsic sensitivity of optoacoustics to multiple hemodynamic and oxygenation parameters,LOT may enable a new level of performance in studying functional and anatomical alterations of microcirculation.

关键词： acoustic diffraction limited-view effects localization optoacoustic imaging photoacoustic imaging super-resolution

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