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Segregation of F-2 interspecific hybrid growth performance and wing color patterns relative to parental species in the Papilio machaon species group （Lepidoptera： Papilionidae）

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Insect Science 2007年第5期14卷 389-400页

作者： j. mark SCRIBER Department of Entomology Michigan State University East Lansing Michigan USA

A strange Papilio female specimen with a prominent yellow wing band type very much like P. brevicauda （and also seen in P. machaon, and P. zelicaon） was captured in the forested mountains of southwest Vermont, USA. Despite its brevicauda-like appearance, it had mt-DNA of P. polyxenes. In eastern North America the P. brevicauda （Maritime Provinces of Canada） is currently believed to reflect previous （ancient） hybridization between ancestral P. machaon and P. polyxenes. It is uncertain whether the brevicauda-like wing trait features in the odd Vermont female may be a result of some introgression of P. machaon or P. brevicauda with P. polyxenes in eastern North America as seen also in the Ozark Mountains with P. joanae. Nonetheless, the significance of wing trait analyses in relation to hybrid zones with P. polyxenes remains relevant. The segregation of wing color patterns and hostplant use abilities （efficiencies and growth rates） were examined for laboratory hand-paired F-2 hybrids of P. zelicaon ~ Papilio polyxenes relative to the parental species and primary hybrids. The black adult color pattern characterizing P. polyxenes is presumed to be inherited as a simple autosomal dominant. These hybrids were examined to determine：（i） how F-1 primary hybrid offspring perform relative to the parental types in survival, growth rates, and growth efficiencies; and （ii） whether these larval traits and the adult color patterns might be linked with wing morphology in the F-2 hybrids. While the F-1 hybrids grew as well as the P. polyxenes parent （P. zelicaon was significantly less efficient and slower in growth than either of these）, we could not convincingly determine whether the growth performances of the F-2 segregants were linked with the parental wing patterns.

关键词： hybrid swarms feeding efficiencies autosomai trait genetics Papilio polyxenes,Papilio zelicaon Papilio brevicauda

Potential Contribution of Combined Atmospheric Ca^(2+) and Mg^(2+) Wet Deposition Within the Continental U.S. to Soil Inorganic Carbon Sequestration

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Pedosphere 2013年第6期23卷 808-814页

作者： E.A.MIKHAILOVA M.A.GODDARD C.j.post M.A.SCHLAUTMAN j.M.GALBRAITH School of Agricultural Forestand Environmental SciencesClemson University Department of Environmental Engineering and Earth Sciences Clemson University Department of Crop and Soil Environmental Sciences Virginia Tech

Soil inorganic carbon （SIC） stocks continuously change from the formation of pedogenic carbonates, a process requiring inputs of Ca2＋ and Mg2＋ ions. This study ranked the soil orders in terms of potential inorganic carbon sequestration resulting from wet Ca2＋ and Mg2＋ deposition from 1994 to 2003 within the continental United States. The analysis revealed that average annual atmospheric wet deposition of Ca2＋ and Mg2＋ was the highest in the Central Midwest-Great Plains region, likely due to soil particle input from loess-derived soils. The soil orders receiving the highest total average annual atmospheric wet Ca2＋ and Mg2＋ deposition, expressed as potential inorganic carbon formation （barring losses from erosion and leaching）, were： 1） Mollisols （1.1 × 10^8 kg C）, 2） Alfisols （8.4 × 10^7 kg C）, 3） Entisols （3.8 × 10^7 kg C）, and 4） Aridisols （2.8 × 10^7 kg C）. In terms of area-normalized result, the soil orders were ranked： 1） Histosols （73 kg C km-2）, 2） Alfisols and Vertisols （64 kg C km-2）, 3） Mollisols （62 kg C km-2）, and 4） Spodosols （52 kg C kin-2）. The results of this study provide an estimate of potential soil inorganic carbon sequestration as a result of atmospheric wet Ca2＋ and Mg2＋ deposition, and this information may be useful in assessing dynamic nature of soil inorganic carbon pools.

关键词： calcite carbon cycle dolomite pedogenic

Efficient ray casting of volumetric images using distance maps for empty space skipping

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Computational Visual Media 2020年第1期6卷 53-63页

作者： Lachlan j.Deakin mark A.Knackstedt Australian National University Canberra2601Australia

Volume and isosurface rendering are methods of projecting volumetric images to two dimensions for *** methods are common in medical imaging and scientific ***-mounted optical see-through displays have recently become an affordable technology and are a promising platform for volumetric image *** displayed on a head-mounted display must be presented at a high frame rate and with low latency to compensate for head *** latency can be jarring and may cause cybersickness which has similar symptoms to motion *** images can be very computationally expensive to render as they often have hundreds of millions of scalar ***,certain materials in images such as air surrounding an object boundary are often made transparent and need not be sampled,which improves rendering *** our previous work we introduced a novel ray traversal technique for rendering large sparse volumetric images at high frame *** method relied on the computation of an occupancy and distance map to speed up ray traversal through empty *** this work we achieve higher frame rates than our previous work with an improved method of resuming empty space skipping and the use of anisotropic Chebyshev distance *** optimised algorithm for computing Chebyshev distance maps on a graphical processing unit is introduced supporting real-time transfer function editing.

关键词： ray casting volume rendering isosurface rendering distance maps

Developing a USLE cover and management factor(C)for forested regions of southern China

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Frontiers of Earth Science 2020年第3期14卷 660-672页

作者： Conghui Li Lili Lin Zhenbang Hao Christopher j.post Zhanghao Chen jian Liu Kunyong Yu Fujian Agriculture and Forestry University Fuzhou350002China University Key Laboratory for Geomatics Technology and Optimized Resources Utilization in Fujian Province Fuzhou350002China Department of Forestry and Environmental Conservation Clemson UniversityClemsonSC29634USA

The Universal Soil Loss Equation model is often used to improve soil resource conservation by monitoring and forecasting soil *** study tested a novel method to determine the cover and management factor(C)of this model by coupling the leaf area index(LAI)and soil basal respiration(SBR)to more accurately estimate a soil erosion map for a typical region with red soil in Hetian,Fujian Province,*** spatial distribution of the LAI was obtained using the normalized difference vegetation index and was consistent with the LAI observed in the field(R^2=0.66).The spatial distribution of the SBR was obtained using the Carnegie-Ames-Stanford Approach model and verified by soil respiration field observations(R^2=0.51).Correlation analyses and regression models suggested that the LAI and SBR could reasonably reflect the structure of the forest canopy and understory vegetation,***,the C-factor was reconstructed using the proposed forest vegetation structure factor(Cs),which considers the effect of the forest canopy and shrub and litter layers on reducing rainfall *** feasibility of this new method was thoroughly verified using runoff plots(R2=0.55).The results demonstrated that Cs may help local governments understand the vital role of the structure of the vegetation layer in limiting soil erosion and provide a more accurate large-scale quantification of the C-factor for soil erosion.

关键词： leaf area index remote sensing soil basal respiration forest vegetation structure factor vegetation layer structure

Heart healthy equals prostate healthy and statins, aspirin, and/or metformin （S.A.M.） are the ideal recommendations for prostate cancer prevention

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Asian journal of Andrology 2015年第5期17卷 783-791,I0008页

作者： mark A Moyad Nicholas j Vogelzang Department of Urology University of Michigan Medical Center Ann Arbor Michigan USA Developmental Therapeutics Committee and Genitourinary Committee for US Oncology Research Comprehensive Cancer Centers of Nevada Las Vegas Nevada USA

Cardiovascular disease （CVD） has been the number one cause of death in the U.S. for 114 of the last 115 years. Lifestyle factors that promote CVD also appear to increase prostate cancer risk and those that reduce CVD risk also appear to reduce the risk of prostate cancer. The largest randomized trials utilizing dietary supplements or pharmacologic agents for prostate cancer prevention （Selenium and Vitamin E Cancer Prevention Trial [SELECT]） have also shed light on the problems and future solutions in this area. Dietary supplements that have not been found to be CVD protective, such as selenium and Vitamin E have not been found to be prostate protective. In addition, over exposure to specific anti-oxidants in nutritionally replete populations may be encouraging cancer growth. Futuretrials of dietary supplements to prevent prostate cancer could be problematic because by the time a definitive trial is initiated the participants will no longer be ＂deficient＂ in the nutrient being tested, which arguably occurred in the SELECT trial. It is also interesting that statins, aspirin, and/or metformin （S.A.M.） are 3 generic, low-cost, heart healthy agents derived from natural sources with separate mechanism of actions, which all appear to have the best benefit to risk ratio compared to any other agent available for prostate cancer prevention, especially aggressive disease, or as an ancillary agent （s） to conventional cancer treatment. It is time to focus on the forest over the trees and recommend proven CVD protective measures for men concerned about their risk of prostate cancer.

关键词： aspirin diet lifestyle metformin prostate cancer statins

Effects of diurnal temperature range on adult size and emergence times from diapausing pupae in Papilio glaucus and R canadensis （Papilionidae）

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Insect Science 2011年第4期18卷 435-442页

作者： j. mark Scriber Brittany Sonke Department of Entomology Michigan State University East Lansing Michigan McGuire Center for Lepidoptera and Biodiversity Flonda Museum of Natural History University of Florida Gainesville Florida USA

With recent climate warming trends, both the increase in thermal variance （i.e., diurnal temperature range; DTR） as well as increased mean temperature may impact many different organisms, especially poikilothermic invertebrates. Predictions of insect developmental rates using degree-days （thermal unit accumulations above the developmental base threshold of the insect） are based on daily mean temperatures, regardless of DTR. However, non-linearity and variance in the means and extremes are often ignored. The role of thermal variance （e.g., daily temperature extremes and DTR） was evaluated experimentally for two swallowtail butterfly sister species using a common day/night photoperiod of 18 ： 6 h photo ： scoto-phase and corresponding daytime thermophase and nighttime cryophase periods of 22 ： 22℃ （constant 22℃）, 24 ： 16℃, and 26 ： 10℃（all three treatments had the same daily mean and the same degree-day accumulations）. Although developmental rates ofpost-diapause pupae were largely unaffected for both species, our results show that sizes in P canadensis females （but not males） were smaller in the treatments with more variance （26℃ ： 10℃） compared to constant 22℃. Such potentially significant impacts of size reduction in P canadensis females were not observed in P glaucus males or females under the same series ofthermo-period treatments.

关键词： climate warming degree-days diurnal temperature range (DTR) photoperiods swallowtail butterflies thermoperiods

Divergence in the ovipositional behavior of the Papilio glaucus group

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Insect Science 2008年第4期15卷 361-367页

作者： Rodrigo j. Mercader j. mark Scriber Department of Entomology Michigan State University East Lansing MI48824 USA

This study contrasts the ovipositional profiles of four members of the Papilio glaucus group, P. glaucus, P. multicaudatus, P. canadensis, and P. rutulus. We used seven choice oviposition bioassays containing leaves from hosts in seven plant families utilized by members of the P. glaucus group. Specifically, we contrast the overall ovipositional profiles of these species and their acceptance of a host in a novel plant family （Populus tremuloides： Salicaceae） and a host in a putatively ancestral host plant family （Liriodendron tulipifera： Magnoliaceae）. Significant differences were observed between the ovipositional profiles of P. glaucus and P. multicaudatus relative to each other and to P. canadensis and P. rutulus. In contrast, no significant differences were observed between the ovipositional profiles of P. canadensis and P. rutulus, which were also the only species that accepted P. tremuloides. Unlike the acceptance of P. tremuloides, the acceptance of L. tulipifera was present throughout the group despite the inability of the larvae of most species in the group to utilize this host. These results support the prediction of the ＂hierarchical threshold model＂ that ancestral host plants are likely to be retained in the ovipositional hierarchy while novel hosts should only be accepted by derived populations.

关键词： host preference insect-plant interactions Lepidoptera Papilionidae

Myeloid immunosuppression and immune checkpoints in the tumor microenvironment

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Cellular & Molecular Immunology 2020年第1期17卷 1-12页

作者： Kyohei Nakamura mark j.Smyth Immunology in Cancer and Infection Laboratory QIMR Berghofer Medical Research InstituteHerston 4006 QLDAustralia

Tumor-promoting inflammation and the avoidance of immune destruction are hallmarks of *** innate immune cells,such as neutrophils,monocytes,and macrophages,are critical mediators for sterile and nonsterile inflammation,persistent inflammation,such as that which occurs in cancer,is known to disturb normal *** disturbance leads to the generation of immunosuppressive myeloid cells,such as myeloid-derived suppressor cells(MDSCs)and tumor-associated macrophages(TAMs).Due to their potent suppressive activities against effector lymphocytes and their abundance in the tumor microenvironment,immunosuppressive myeloid cells act as a major barrier to cancer ***,various therapeutic approaches directed toward immunosuppressive myeloid cells are actively being tested in preclinical and clinical *** include antiinflammatory agents,therapeutic blockade of the mobilization and survival of myeloid cells,and immunostimulatory *** recently,immune checkpoint molecules expressed on tumor-infiltrating myeloid cells have emerged as potential therapeutic targets to redirect these cells to eliminate tumor *** this review,we discuss the complex crosstalk between cancer-related inflammation and immunosuppressive myeloid cells and possible therapeutic strategies to harness antitumor immune responses.

关键词： myeloid macrophage innate immunity immune checkpoint inflammation

Intraventricular neurocysticercosis: Presentation, diagnosis and management

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Asian Pacific journal of Tropical Medicine 2016年第8期9卷 792-795页

作者： Tomas Ostergaard jensen jeffrey john post Department of Infectious Diseases Prince of Wales Hospital

Neurocysticercosis is thought to be the most common helminthic infection of the central nervous system and its epidemiology is changing due to increasing travel and *** to guide management of the intraventricular form is *** aimed to review the clinical presentation,diagnosis and treatment of intraventricular neurocysticercosis with reference to two recent cases seen at our *** intraventricular variant of neurocysticercosis is less common than parenchymal disease and usually presents with acutely raised intracranial pressure and untreated it progresses rapidly with high *** diagnosis is based on imaging and serological tests but more invasive testing including histopathological examination of surgically acquired tissue specimens is sometimes *** is mainly surgical,using a neuroendoscopic approach if *** should also receive antihelmintic treatment with concomitant corticosteroids to reduce the incidence of shunt failure if a ventricular shunt is inserted and to treat viable lesions elsewhere.

关键词： Taenia solium Cysticercosis Neurocysticercosis Intraventricular Human Adult