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Heuristic Estimation of the Vacuum Energy Density of the Universe: Part II-Analysis Based on Frequency Domain Electromagnetic Radiation

2005年

作者： Frederick S. Hillier gerald j. lieberman.

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j.urnal of Electromagnetic Analysis and Applications 2024年第1期16卷 1-9页

作者： Vernon Cooray gerald Cooray Marcos Rubinstein Farhad Rachidi Department of Electrical Engineering Uppsala University Uppsala Sweden Karolinska Institute Stockholm Sweden HEIG-VD University of Applied Sciences and Arts Western Switzerland Yverdon-les-Bains Switzerland Electromagnetic Compatibility Laboratory Swiss Federal Institute of Technology (EPFL) Lausanne Switzerland

In Part I of this paper, an inequality satisfied by the vacuum energy density of the universe was derived using an indirect and heuristic procedure. The derivation is based on a proposed thought experiment, according to which an electron is accelerated to a constant and relativistic speed at a distance L from a perfectly conducting plane. The charge of the electron was represented by a spherical charge distribution located within the Compton wavelength of the electron. Subsequently, the electron is incident on the perfect conductor giving rise to transition radiation. The energy associated with the transition radiation depends on the parameter L. It was shown that an inequality satisfied by the vacuum energy density will emerge when the length L is pushed to cosmological dimensions and the product of the radiated energy, and the time duration of emission is constrained by Heisenberg’s uncertainty principle. In this paper, a similar analysis is conducted with a chain of electrons oscillating sinusoidally and located above a conducting plane. In the thought experiment presented in this paper, the behavior of the energy radiated by the chain of oscillating electrons is studied in the frequency domain as a function of the length L of the chain. It is shown that when the length L is pushed to cosmological dimensions and the energy radiated within a single burst of duration of half a period of oscillation is constrained by the fact that electromagnetic energy consists of photons, an inequality satisfied by the vacuum energy density emerges as a result. The derived inequality is given by where is the vacuum energy density. This result is consistent with the measured value of the vacuum energy density, which is 5.38 × 10-10 j.m. The result obtained here is in better agreement with experimental data than the one obtained in Part I of this paper with time domain radiation.

关键词： Classical Electrodynamics Electromagnetic Radiation Action Radiated Energy Photon Heisenberg’s Uncertainty Principle Dark Energy Vacuum Energy Cosmological Constant Hubble Radius

Introduction to Operations Research 7th ed.

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Quantitative Analysis of Marine Biological Communities: Field Biology and Environment

丛书名： McGraw-Hill series in industrial engineering and management science

2001年

作者： Frederick S. Hillier gerald j. lieberman

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Transformer2 proteins protect breast cancer cells from accumulating replication stress by ensuring productive splicing of checkpoint kinase 1

2007年

作者： gerald j. Bakus

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Frontiers of Chemical Science and Engineering 2016年第2期10卷 186-195页

作者： Andrew Best Katherine j.mes gerald Hysenaj.Alison Tyson-Capper David j. Elliott Institute of Genetic Medicine Newcastle University Newcastle NE1 3BZ UK Interdisciplinary Computing and Complex BioSystems Research Group and Centre for Bacterial Cell Biology Newcastle University Newcastle NE1 3BZ UK Institute for Cellular Medicine Newcastle University Newcastle NE2 4HH UK

Increased expression levels of the RNA splicing regulator Transformer2fl （abbreviated Tra2fl） have been reported in several types of cancer. Recent work has revealed an intimate cross-regulation between Tra2fl and the highly similar Tra2a protein in human breast cancer cells, though these two proteins are encoded by separate genes created by a gene duplication that occurred over 500 million years ago. This cross-regulation involves splicing control of a special class of exons, called poison exons. Down-regulation of Tra2fl reduces splicing inclu- sion of a poison exon in the mRNA encoding Tra2a, thereby up-regulating Tra2a protein expression. This buffers any splicing changes that might be caused by individual depletion of Tra2fl alone. Discovery of this cross-regulation pathway, and its by-pass by j.int deple- tion of both human Tra2 proteins, revealed Tra2 proteins are essential for breast cancer cell viability, and led to the identification of important targets for splicing control. These exons include a critical exon within the checkpoint kinase 1 （CHK1） gene that plays a crucial function in the protection of cancer cells from replication stress. Breast cancer cells depleted for Tra2 proteins have reduced CHK1 protein levels and accumulate DNA damage. These data suggest Tra2 proteins and/or their splicing targets as possible cancer drug targets.

关键词： RNA splicing gene expression breast cancer,DNA damage CHK1

INTERACTION BETWEEN ESTUARINE PLUMES AND COASTAL WATERS

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Science China Mathematics 1988年第10期31卷 1222-1239页

作者：张庆华,LEONARD j. PIETRAFESA,gerald S. j.NOWITZ Institute of Oceanology Academia Sinica Qingdao Department of Marine Earth and Atmospheric Sciences NCSU Raleigh NC USA Department of Marine Earth and Atmospheric Sciences NCSU Raleigh NC USA

A simple analytical model is developed to describe the steady flow in an estuary-shelf interaction region where the water is treated as a two-layer density stratified flow. The motion is expanded in terms of the relative thickness of the vertical Ekman layer. The order-zero flow is geostrophic in each layer. Balancing the one-order quantities, an explicit solution of streamlines is obtained for the case of linear offshore sloping bottom. The flow behaviour of the river water plume depends on the vertical structure of the flow at the river mouth, the bottom slope and the ambient coastal flow. Under certain conditions, a salinity front exists as an offshore boundary of the river plume. These results are compared with observations of the Changj.ang River (in China,) and the Chesapeake Bay (in US) estuaries.

关键词： estuary-shelf interaction estuarine plumes coastal waters.

Using fluorescence-based microplate assay to assess DOM-metal binding in reactive materials for treatment of acid mine drainage

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j.urnal of Environmental Sciences 2011年第6期23卷 891-896页

作者： Carmen Mihaela Neculita Yves Dudal gerald j.Zagury Department of Civil and Environmental Engineering KAIST335 GwahangnoYuseong-guDaejeon 305-701Korea Institut National de la Recherche Agronomique UMR Eco&Sols-Ecologie Fonctionnelle et Biogéochimie des SolsMontpellier SupAgro-INRA-IRD2Place Pierre VialaBatiment 1234060 Montpellier Cedex 2France Department of Civil Geologicaland Mining EngineeringE'cole Polytechnique de Montre'alC.P.6079 Station Centre-villeMontrealQCH3C 3A7Canada

One potential drawback of compost-based passive bioreactors,which is a promising biotechnology for acid mine drainage（AMD） treatment,is the transport of dissolved organic matter（DOM）-metal complexes in surface *** address this problem,the obj.ctive of this study was to assess the maximum capacity of organic substrates to release soluble DOM-metal complexes in treated water. The reactivities of DOM in maple wood chips and sawdust,composted poultry manure,and leaf compost were quantified toward Cd2＋,Ni2＋,Fe2＋,and Cu2＋ using fluorescence *** DOM showed the highest reactivity toward Fe,but a limited number of available sites for sorption,whereas DOM-Cd complexes exhibited the lowest fluorescence ***,the DOM from a mixture of wastes formed higher concentrations of DOM-metal complexes relative to sole *** DOM-metal complexes, the concentrations of DOM-Ni complexes were the *** reaching steady-state,low concentrations of DOM-metal complexes were released in treated water,which is in agreement with theoretical predictions based on geochemical ***,in addition to physicochemical characterization,fluorescence quenching technique is recommended for the substrate selection of bioreactors.

关键词： passive bioreactors acid mine drainage DOM reactivity fluorescence quenching metal complexation

Assessing the influence of harvesting intensities on structural diversity of forests in south-west Germany

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Forest Ecosystems 2019年第3期6卷 249-260页

作者： Felix Storch gerald Kadler j.rgen Bauhus Chair of Silviculture University of FreiburgD-79085 FreiburgGermany Department of Biometry Forest Research Institute of Baden-WürttembergD-79100 FreiburgGermany

Background: To increase ecosystem resilience and biodiversity, the maintenance and improvement of structural and compositional diversity of forests has become an important goal in forest management for many forest owners and j.risdictions. At the same time, future harvesting intensity (HI) may increase to meet the demand for woody biomass by an increasing bioeconomy sector. Yet, the influence of HI on forest structural diversity is largely unknown. Here, we address this issue by analyzing the relationship between HI and structural diversity based on large-scale national forest inventory (NFI) data, where the latter is quantified using a previously developed Forest Structure Index and HI is expressed as wood volume removal during the period 2002-2012 for the same inventory plots. Results: Our results show a surprisingly small impact of harvesting intensity on changes in structural diversity for most of the analysed types of forests. Only intense harvesting (> 80%-90% of initial growing stock) led to a significant reduction in structural diversity. At low to moderate HI most aspects of structural diversity were positively influenced. Only the quadratic mean DBH and the volume of large trees (≥ 40 cm DBH) were substantially negatively influenced at HI > 60% and 70% of initial growing stock, respectively. Conclusions: In several forest types, HI could be increased without a reduction in overall structural diversity. Hence, structural diversity in these selectively managed forests appears to be a very resistant forest property in relation to HI. Other indicators at stand and landscape scale may be needed to adj.st levels of HI that are suited to maintain forest biodiversity.

关键词： Large-scale inventory Structural diversity index Harvesting intensity Changes in structural diversity

Strategies to improve fiber utilization in swine

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j.urnal of Animal Science and Biotechnology 2013年第2期4卷 112-123页

作者： Brian j.Kerr gerald C Shurson USDA-ARS-National Laboratory for Agriculture and the Environment University of Minnesota

Application of feed processing methods and use of exogenous feed additives in an effort to improve nutrient digestibility of plant-based feed ingredients for swine has been studied for decades. The following review will discuss several of these topics, including： fiber characterization, impact of dietary fiber on gastrointestinal physiology, energy, and nutrient digestibility, mechanical processing of feed on fiber and energy digestibility, and the use of exogenous enzymes in diets fed to growing pigs. Taken together, the diversity and concentration of chemical characteristics that exists among plant-based feed ingredients, as well as interactions among constituents within feed ingredients and diets, suggests that improvements in nutrient digestibility and pig performance from mechanical processing or adding exogenous enzymes to diets fed to swine depends on a better understanding of these characteristics, but also relating enzyme activity to targeted substrates. It may be that an enzyme must not only match a target substrate（s）, but there may also need to be a ＇cocktail＇ of enzymes to effectively breakdown the complex matrixes of fibrous carbohydrates, such that the negative impact of these compounds on nutrient digestibility or voluntary feed intake are alleviated. With the inverse relationship between fiber content and energy digestibility being well described for several feed ingredients, it is only logical that development of processing techniques or enzymes that degrade fiber, and thereby improve energy digestibility or voluntary feed intake, will be both metabolically and economically beneficial to pork production.

关键词： Energy Enzymes Fiber Growing-finishing pigs Nutrient digestibility Processing

Evaluating the quality of feed fats and oils and their effects on pig growth performance

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j.urnal of Animal Science and Biotechnology 2016年第3期7卷 330-340页

作者： gerald C Shurson Brian j.Kerr Andrea R Hanson Department of Animal Science University of MinnesotaStPaulMN 55018USA usda-ars-national laboratory for agriculture and the environment Ames IA 50011USA svc-research St PeterMN 56082USA

Feed fats and oils provide significant amounts of energy to swine diets, but there is large variation in composition,quality, feeding value, and price among sources. Common measures of lipid quality include moisture, insolubles,and unsaponifiables（MIU）, titer, and free fatty acid content, but provide limited information regarding their feeding value. Lipid peroxidation is an important quality factor related to animal growth performance and health, but maximum tolerable limits in various lipids have not been established. Several indicative assays can be used to detect the presence of various peroxidation compounds, but due to the complexity and numerous compounds produced and degraded during peroxidation process, no single method can adequately determine the extent of peroxidation. Until further information is available, using a combination of peroxide value, thiobarbituric acid reactive substances（TBARS）, and anisidine value appear to provide a reasonable assessment of the extent of peroxidation in a lipid at a reasonable cost. However, fatty acid composition of the lipid being evaluated should be considered when selecting specific assays. Predictive tests can also be used to estimate the stability or susceptibility of lipids to peroxidation and include active oxygen method, oil stability index, and oxygen bomb method. A review of 16 published studies with pigs has shown an average decrease of 11.4% in growth rate, 8.8% feed intake fed isocaloric diets containing peroxidized lipids compared to diets containing unperoxidized lipids of the same ***, serum vitamin E content was generally reduced and serum TBARS content was increased when peroxidized lipids were fed in these studies, suggesting that feeding peroxidized lipids negatively affects metabolic oxidative status of pigs. However, it is unclear if antioxidants are useful additions to lipids to maintain optimal nutritional value, or if their addition to swine diets is beneficial in overcoming a met

关键词： Growth Indicative tests Lipids Metabolic oxidation Peroxidation Pigs