bluuebunny/crossref_metadata_2025 huggingface dataset:
Nanostructured Triblock Copolymer Network With Tailorable Electroactive Response
Authors: Krishnan Arjun S. , Shankar Ravi , Ghosh Tushar K. , Spontak Richard J.
Published: July 2009

In recent years, the use of electroactive polymers (EAPs), which are polymeric materials that respond to an external electrical stimulus by changing shape or size, has been the focus of considerable research effort. While most studies have considered chemically cross-linked homopolymers, only a few reports have addressed the use of physically cross-linked triblock copolymer systems. We have previously demonstrated that triblock copolymer networks swollen by a midblock-selective, nonvolatile solvent constitute excellent candidates as dielectric elastomers, one class of EAP materials. Due to the presence of a molecularly self-organized nanostructure in such materials, this EAP genre is generally referred to as electro-active nanostructured polymers (ENPs). These systems not only exhibit high actuation strains (>200%), but are also amenable to facile processing and recycling. In this study, we examine the electromechanical response of symmetric triblock copolymers possessing styrenic endblocks and a rubbery midblock selectively solvated with an aliphatic mineral oil. Our findings show that the specimen thickness has a significant effect on the electroactive response of the system. Moreover, we are able to correlate the electromechanical properties of ENPs with their mechanical properties.
Magnetorheological Shock Absorber for Crew Seats in the Expeditionary Fighting Vehicle
Authors: Hu Wei , Wilson Nicholas , Hiemenz Gregory J. , Wereley Norman M.
Published: July 2009

A magnetorheological shock absorber (MRSA) system is designed and tested to integrate semi-active shock and vibration mitigating technology into the existing EFV (Expeditionary Fighting Vehicle) forward seating positions. Based on the operational requirements of the vehicle, the MRSA is designed so that it can not only isolate occupants from harmful whole body vibration (WBV) during normal operations but also reduce injury risk during extreme events such as a “rogue” wave or ballistic/UNDEX shock event. The MRSA consists of a piston with a circular flow-mode valve, a magnetorheological (MR) fluid cylinder, and a nitrogen accumulator. Piston motion forces MR fluids enclosed in the fluid cylinder to flow through the valve where it is activated by a magnetic field in the valve. Based on the Bingham-plastic constitutive relation and a steady state fluid motion model, the valve parameters are determined using a magnetic circuit analysis tool and are validated by electromagnetic finite element analysis (FEA). The high-speed field-off viscous force of the MRSA is predicted using computational fluid dynamic analysis. To experimentally evaluate the damping performance of the MRSA and validate the design, the MRSA is tested under single frequency sinusoidal displacement excitation on a material dynamic testing machine for low piston velocities (up to 0.9 m/s) performance evaluation. For performance evaluation at high piston velocities (up to 2.2 m/s), the MRSA is tested under impact loading on a rail-guided mass-drop test stand. Equivalent viscous damping is used to characterize the controllable damping behavior of the MRSA. To describe the time response of the MRSA, a dynamic model is developed based on geometrical parameters and MR fluid properties.
Behavior of Magnetorheological Fluids Employing Carrier Fluids Certified for Landing Gear Use
Authors: Ahure´ Louise , Wereley Norman M.
Published: July 2009

Magnetorheological (MR) fluids were prepared in order to investigate their performance for potential use in landing gear hydraulic systems, such as shock struts. MR fluids formulated here utilized three hydraulic oils certified for use in landing gear, two different average diameters of spherical magnetic particles, and a Lecithin surfactant. The fluids were characterized in order to measure and analyze their rheological behavior. Therefore, different characteristics were taken into consideration, such as 1) magnetorheology as a function of magnetic field, 2) cycling of a small-scale damper undergoing sinusoidal excitations at frequencies of 2.5 and 5 Hz, and 3) sedimentation analysis conducted with an inductance-based sensor. The goal of this research is to analyze the performance of these particular MR fluids, to compare their behavior to standard commercial MR fluids, and to determine their feasibility for use in helicopter landing gear.
Response to Comment by Goldberg
et al.
on “DNA from Pre-Clovis Human Coprolites in Oregon, North America”
Authors: Rasmussen Morten , Cummings Linda Scott , Gilbert M. Thomas P. , Bryant Vaughn , Smith Colin , Jenkins Dennis L. , Willerslev Eske
Published: July 2009

Goldberg
et al
. use data from micromorphological and Fourier transform infrared analyses to argue that Paisley Cave pre-Clovis coprolite 1374-5/5D-31-2 is of herbivore, rather than human, origin. We argue that the diagnostic capability of the techniques used by Goldberg
et al
. are limited, and we present new genetic data that support our original claims.
Comment on “DNA from Pre-Clovis Human Coprolites in Oregon, North America”
Authors: Poinar Hendrik , Fiedel Stuart , King Christine E. , Devault Alison M. , Bos Kirsti , Kuch Melanie , Debruyne Regis
Published: July 2009

Gilbert
et al
. (Reports, 9 May 2008, p. 786) analyzed DNA from radiocarbon-dated paleofecal remains from Paisley Cave, Oregon, which ostensibly demonstrate a human presence in North America predating the well-established Clovis complex. We question the authenticity of their DNA results and argue that in the absence of intact stratigraphy and diagnostic artifacts, and in view of carbon isotope anomalies, the radiocarbon dates of the oldest specimens are unreliable.
Predicting Fatigue Failures
Authors: Kruzic Jamie J.
Published: July 2009

New methods for predicting fatigue may extend the usefulness of materials that actively resist cracking.
Oriented Assembly of Metamaterials
Authors: Stebe Kathleen J. , Lewandowski Eric , Ghosh Moniraj
Published: July 2009

The creation of complex materials may be aided by advanced colloidal assembly methods involving anisotropically shaped particles.
Sunspot Flows and Filaments
Authors: Scharmer Göran
Published: July 2009

Numerical simulations capture the detailed structure and dynamics of sunspots.
Evolving Artists
Authors: Balter Michael
Published: July 2009

Judging from the successful few whose work shapes our ideas of ancient humans (
see main text
), there's no standard career path, but hefty doses of both artistic talent and scientific knowledge are essential to become a paleoartist.
Putative Novel Surface-Exposed
Streptococcus agalactiae
Protein Frequently Expressed by the Group B Streptococcus from Zimbabwe
Authors: Mavenyengwa Rooyen T. , Maeland Johan A. , Moyo Sylvester R.
Published: July 2009

Group B streptococci (GBS) express a variety of surface-exposed and strain-variable proteins which function as phenotypic markers and as antigens which are able to induce protective immunity in experimental settings. Among these proteins, the chimeric and immunologically cross-reacting alpha-like proteins are particularly important. Another protein, R3, which has been less well studied, occurred at a frequency of 21.5% in GBS from Zimbabwe and, notably, occurred in serotype V strains at a frequency of 75.9%. Working with rabbit antiserum raised against the R3 reference strain ATCC 49447 (strain 10/84; serotype V/R3) to detect the expression of the R3 protein, we recorded findings which suggested that strain 10/84 expressed a strain-variable protein antigen, in addition to R3. The antigen was detected by various enzyme-linked immunosorbent assay-based tests by using acid extract antigens or GBS whole-cell coats and by whole-cell-based Western blotting. We named the putative novel antigen the Z antigen. The Z antigen was a high-molecular-mass antigen that was susceptible to degradation by pepsin and trypsin but that was resistant to
m
-periodate oxidation and failed to show immunological cross-reactivity with any of a variety of other GBS protein antigens. The Z antigen was expressed by 33/121 (27.2%) of strains of a Zimbabwean GBS strain collection and by 64.2% and 72.4% of the type Ib and type V strains, respectively, and was occasionally expressed by GBS of other capsular serotypes. Thus, the putative novel GBS protein named Z showed distinct capsular antigen associations and presented as an important phenotypic marker in GBS from Zimbabwe. It may be an important antigen in GBS from larger areas of southern Africa. Its prevalence in GBS from Western countries is not known.
False-Negative Results Obtained with the Gen-Probe Amplified
Mycobacterium
tuberculosis
Direct Test Caused by Unrecognized Inhibition of the Amplification Reaction
Authors: Kim Ji Yeon , Ferraro Mary Jane , Branda John A.
Published: July 2009

The Gen-Probe Amplified
Mycobacterium tuberculosis
direct test is widely used in the diagnosis of tuberculosis. Specimens may contain amplification inhibitors, potentially leading to false-negative results if unrecognized. We report a failure to detect inhibition, despite adherence to the inhibition testing guidelines provided on the label, and recommend changes.
Transcriptional Changes in the Brains of Cattle Orally Infected with the Bovine Spongiform Encephalopathy Agent Precede Detection of Infectivity
Authors: Tang Yue , Xiang Wei , Hawkins Steve A. C. , Kretzschmar Hans A. , Windl Otto
Published: July 2009

Bovine spongiform encephalopathy (BSE) is a fatal, transmissible, neurodegenerative disease of cattle. BSE can be transmitted experimentally between cattle through the oral route, and in this study, brain tissue samples from animals at different time points postinoculation were analyzed for changes in gene expression. The aims of this study were to identify differentially regulated genes during the progression of BSE using microarray-based gene expression profiling and to understand the effect of prion pathogenesis on gene expression. A total of 114 genes were found to be differentially regulated over the time course of the infection, and many of these 114 genes encode proteins involved in immune response, apoptosis, cell adhesion, stress response, and transcription. This study also revealed a broad correlation between gene expression profiles and the progression of BSE in cattle. At 21 months postinoculation, the largest number of differentially regulated genes was detected, suggesting that there are many pathogenic processes in the animal brain even prior to the detection of infectivity in the central nervous systems of these orally infected cattle. Moreover, evidence is presented to suggest that it is possible to predict the infectious status of animals using the expression profiles from this study.
Ebolavirus Glycoprotein GP Masks both Its Own Epitopes and the Presence of Cellular Surface Proteins
Authors: Reynard Olivier , Borowiak Malgorzata , Volchkova Valentina A. , Delpeut Sebastien , Mateo Mathieu , Volchkov Viktor E.
Published: July 2009

Ebolavirus (EBOV) is the etiological agent of a severe hemorrhagic fever with a high mortality rate. The spike glycoprotein (GP) is believed to be one of the major determinants of virus pathogenicity. In this study, we demonstrated the molecular mechanism responsible for the downregulation of surface markers caused by EBOV GP expression. We showed that expression of mature GP on the plasma membrane results in the masking of cellular surface proteins, including major histocompatibility complex class I. Overexpression of GP also results in the masking of certain antigenic epitopes on GP itself, causing an illusory effect of disappearance from the plasma membrane.
The Closest Relatives of Icosahedral Viruses of Thermophilic Bacteria Are among Viruses and Plasmids of the Halophilic Archaea
Authors: Jalasvuori Matti , Jaatinen Silja T. , Laurinavičius Simonas , Ahola-Iivarinen Elina , Kalkkinen Nisse , Bamford Dennis H. , Bamford Jaana K. H.
Published: July 2009

We have sequenced the genome and identified the structural proteins and lipids of the novel membrane-containing, icosahedral virus P23-77 ofThermus thermophilus. P23-77 has an ∼17-kb circular double-stranded DNA genome, which was annotated to contain 37 putative genes. Virions were subjected to dissociation analysis, and five protein species were shown to associate with the internal viral membrane, while three were constituents of the protein capsid. Analysis of the bacteriophage genome revealed it to be evolutionarily related to anotherThermusphage (IN93), archaealHalobacteriumplasmid (pHH205), a genetic element integrated intoHaloarculagenome (designated here as IHP for integratedHaloarculaprovirus), and theHaloarculavirus SH1. These genetic elements share two major capsid proteins and a putative packaging ATPase. The ATPase is similar with the ATPases found in the PRD1-type viruses, thus providing an evolutionary link to these viruses and furthering our knowledge on the origin of viruses.
Two Small RNAs Encoded within the First 1.5 Kilobases of the Herpes Simplex Virus Type 1 Latency-Associated Transcript Can Inhibit Productive Infection and Cooperate To Inhibit Apoptosis
Authors: Shen Wenwen , Sa e Silva Mariana , Jaber Tareq , Vitvitskaia Olga , Li Sumin , Henderson Gail , Jones Clinton
Published: July 2009

The herpes simplex virus type 1 (HSV-1) latency-associated transcript (LAT) is abundantly expressed in latently infected trigeminal ganglionic sensory neurons. Expression of the first 1.5 kb of LAT coding sequences is sufficient for the wild-type reactivation phenotype in small animal models of infection. The ability of the first 1.5 kb of LAT coding sequences to inhibit apoptosis is important for the latency-reactivation cycle. Several studies have also concluded that LAT inhibits productive infection. To date, a functional LAT protein has not been identified, suggesting that LAT is a regulatory RNA. Two small RNAs (sRNAs) were previously identified within the first 1.5 kb of LAT coding sequences. In this study, we demonstrated that both LAT sRNAs were expressed in the trigeminal ganglia of mice latently infected with an HSV-1 strain that expresses LAT but not when mice were infected with a LAT null mutant. LAT sRNA1 and sRNA2 cooperated to inhibit cold shock-induced apoptosis in mouse neuroblastoma cells. LAT sRNA1, but not LAT sRNA2, inhibited apoptosis less efficiently than both sRNAs. When rabbit skin cells were cotransfected with plasmids that express LAT sRNA1 and HSV-1 genomic DNA, the amount of infectious virus released was reduced approximately 3 logs. Although LAT sRNA2 was less effective at inhibiting virus production, it inhibited expression of infected cell protein 4 (ICP4). Neither LAT sRNA had an obvious effect on ICP0 expression. These studies suggested that expression of two LAT sRNAs plays a role in the latency-reactivation cycle by inhibiting apoptosis and productive infection.
Increased eIF2α Phosphorylation Attenuates Replication of Herpes Simplex Virus 2 vhs Mutants in Mouse Embryonic Fibroblasts and Correlates with Reduced Accumulation of the PKR Antagonist ICP34.5
Authors: Wylie Kristine M. , Schrimpf Jane E. , Morrison Lynda A.
Published: July 2009

Herpes simplex virus 2 (HSV-2) strains containing mutations in the virion host shutoff (vhs) protein are attenuated for replication compared with wild-type virus in mouse embryonic fibroblasts (MEFs). However, HSV-2 vhs mutants replicate to near wild-type levels in the absence of the RNA-activated protein kinase (PKR). PKR is one of several kinases that phosphorylates the eukaryotic initiation factor 2α (eIF2α) to inhibit translation initiation, and we previously found that more of the phosphorylated form of eIF2α accumulates in MEFs infected with HSV-2 vhs mutants than with wild-type virus. Here, we show that this increase in phosphorylated eIF2α is primarily PKR dependent. Using MEFs expressing nonphosphorylatable eIF2α, we demonstrate that phosphorylated eIF2α is the primary cause of attenuated replication of HSV-2 vhs mutants and that attenuation correlates with decreased accumulation of viral proteins. Normally, HSV antagonizes eIF2α phosphorylation through the action of ICP34.5, which redirects protein phosphatase 1α (PP1α) to dephosphorylate eIF2α during infection. We show that ICP34.5 does not accumulate efficiently in MEFs infected with HSV-2 vhs mutant viruses, suggesting that the accumulation of phosphorylated eIF2α and the attenuated phenotype of HSV-2 vhs mutants in MEFs result from a deficiency in ICP34.5.
Impact of Cytotoxic-T-Lymphocyte Memory Induction without Virus-Specific CD4
+
T-Cell Help on Control of a Simian Immunodeficiency Virus Challenge in Rhesus Macaques
Authors: Tsukamoto Tetsuo , Takeda Akiko , Yamamoto Takuya , Yamamoto Hiroyuki , Kawada Miki , Matano Tetsuro
Published: July 2009

Despite many efforts to develop AIDS vaccines eliciting virus-specific T-cell responses, whether induction of these memory T cells by vaccination before human immunodeficiency virus (HIV) exposure can actually contribute to effective T-cell responses postinfection remains unclear. In particular, induction of HIV-specific memory CD4
+
T cells may increase the target cell pool for HIV infection because the virus preferentially infects HIV-specific CD4
+
T cells. However, virus-specific CD4
+
helper T-cell responses are thought to be important for functional CD8
+
cytotoxic-T-lymphocyte (CTL) induction in HIV infection, and it has remained unknown whether HIV-specific memory CD8
+
T cells induced by vaccination without HIV-specific CD4
+
T-cell help can exert effective responses after virus exposure. Here we show the impact of CD8
+
T-cell memory induction without virus-specific CD4
+
T-cell help on the control of a simian immunodeficiency virus (SIV) challenge in rhesus macaques. We developed a prophylactic vaccine by using a Sendai virus (SeV) vector expressing a single SIV Gag
241-249
CTL epitope fused with enhanced green fluorescent protein (EGFP). Vaccination resulted in induction of SeV-EGFP-specific CD4
+
T-cell and Gag
241-249
-specific CD8
+
T-cell responses. After a SIV challenge, the vaccinees showed dominant Gag
241-249
-specific CD8
+
T-cell responses with higher effector memory frequencies in the acute phase and exhibited significantly reduced viral loads. These results demonstrate that virus-specific memory CD8
+
T cells induced by vaccination without virus-specific CD4
+
T-cell help could indeed facilitate SIV control after virus exposure, indicating the benefit of prophylactic vaccination eliciting virus-specific CTL memory with non-virus-specific CD4
+
T-cell responses for HIV control.
Insight into Poliovirus Genome Replication and Encapsidation Obtained from Studies of 3B-3C Cleavage Site Mutants
Authors: Oh Hyung Suk , Pathak Harsh B. , Goodfellow Ian G. , Arnold Jamie J. , Cameron Craig E.
Published: July 2009

A poliovirus (PV) mutant (termed GG), which is incapable of producing 3AB, VPg, and 3CD proteins due to a defective cleavage site between the 3B and 3C proteins, replicated, producing 3BC-linked RNA rather than the VPg-linked RNA produced by the wild type (WT). GG PV RNA is quasi-infectious. The yield of infectious GG PV relative to replicated RNA is reduced by almost 5 logs relative to that of WT PV. Proteolytic activity required for polyprotein processing is normal for the GG mutant. 3BC-linked RNA can be encapsidated as efficiently as VPg-linked RNA. However, a step after genome replication but preceding virus assembly that is dependent on 3CD and/or 3AB proteins limits production of infectious GG PV. This step may involve release of replicated genomes from replication complexes. A pseudorevertant (termed EG) partially restored cleavage at the 3B-3C cleavage site. The reduced rate of formation of 3AB and 3CD caused corresponding reductions in the observed rate of genome replication and infectious virus production by EG PV without impacting the final yield of replicated RNA or infectious virus relative to that of WT PV. Using EG PV, we showed that genome replication and encapsidation were distinct steps in the multiplication cycle. Ectopic expression of 3CD protein reversed the genome replication phenotype without alleviating the infectious-virus production phenotype. This is the first report of a
trans
-complementable function for 3CD for any picornavirus. This observation supports an interaction between 3CD protein and viral and/or host factors that is critical for genome replication, perhaps formation of replication complexes.
Block and shear-zone architecture of the Minnesota River Valley subprovince: implications for late Archean accretionary tectonics
Authors: Southwick D. L. , Chandler Val W.
Published: July 2009

The Minnesota River Valley subprovince of the Superior Province is an Archean gneiss terrane composed internally of four crustal blocks bounded by three zones of east-northeast-trending linear geophysical anomalies. Two of the block-bounding zones are verified regional-scale shears. The geological nature of the third boundary has not been established. Potential-field geophysical models portray the boundary zones as moderately north-dipping surfaces or thin slabs similar in strike and dip to the Morris fault segment of the Great Lakes tectonic zone at the north margin of the subprovince. The central two blocks of the subprovince (Morton and Montevideo) are predominantly high-grade quartzofeldspathic gneiss, some as old as 3.6 Ga, and late-tectonic granite. The northern and southern blocks (Benson and Jeffers, respectively) are judged to contain less gneiss than the central blocks and a larger diversity of syntectonic and late-tectonic plutons. A belt of moderately metamorphosed mafic and ultramafic rocks having some attributes of a dismembered ophiolite is partly within the boundary zone between the Morton and Montevideo blocks. This and the other block boundaries are interpreted as late Archean structures that were reactivated in the Early Proterozoic. The Minnesota River Valley subprovince is interpreted as a late accretionary addition to the Superior Province. Because it was continental crust, it was not subductible when it impinged on the convergent southern margin of the Superior Craton in late Archean time, and it may have accommodated to convergent-margin stresses by dividing into blocks and shear zones capable of independent movement.
Continental slope sedimentation in the Sheepbed Formation (Neoproterozoic, Windermere Supergroup), Mackenzie Mountains, N.W.T.
Authors: Dalrymple R. W. , Narbonne G. M.
Published: July 2009

The Sheepbed Formation (Ediacaran) is a 1 km thick, siliciclastic unit that overlies glacial deposits of the Ice Brook Formation and is overlain by carbonates of the Gametrail Formation. Observations in the Mackenzie Mountains indicate that the Sheepbed Formation accumulated in water depths of 1–1.5 km on a passive-margin, continental slope. The lower part of the formation consists predominately of dark mudstone. Fine-grained, turbiditic sandstone becomes more abundant upward, as does the scale and abundance of slope-instability indicators. Mesoscale facies successions (i.e., evidence of channels, lobes, and (or) compensation cycles) are developed in the upper half of the formation. The larger-scale changes are interpreted as reflecting a postglacial sea-level rise, followed by a relative fall and an increase in the rate of deposition. Contourites that may have been formed in response to the circulation of deep, cold water occur in the lowstand deposits. Their presence confirms previous speculation that the proto-Pacific Ocean was initiated at the beginning of Windermere deposition (ca. 780 Ma), not at the start of the Cambrian. The paleoflow direction toward the present-day northwest suggests that this part of Laurentia lay in the northern hemisphere. In situ Ediacaran megafossils are preserved on the soles of sandy turbidites; the deep-water setting indicates that these organisms were not photoautotrophs.
Petrography and depositional environment of coal seams in the Carboniferous Morien Group, Sydney Coalfield, Nova Scotia
Authors: Marchioni D. , Gibling M. , Kalkreuth W.
Published: July 2009

The Morien Group (Westphalian A – Stephanian) of the Sydney Basin, Nova Scotia, contains numerous coal seams, many of which can be traced across the onshore part of the basin. Depositional environments during coal formation range from proximal, fluvially dominated to intercalated distal fluvial, to restricted marine. Most of the coal samples analyzed in this study come from the Bras d'Or section, a near-continuous coastal exposure of the Sydney Mines Formation. Petrographic compositions of the samples are discussed in the context of the depositional setting of the enclosing strata. The coal seams have a high vitrinite content (70–90 vol. %), with moderate inertinite and low liptinite. Petrographic indices suggest that most coals of the Sydney Mines Formation are similar to seams deposited in interdistributary or lower delta plain settings in other basins and provide support for the interpreted sedimentological setting of this sequence. The coal seams of the Bras d'Or section show little variation in gross petrographic composition relative to their stratigraphic position, although a slight trend of increasing vitrinite content towards the upper part of the sequence may indicate peat accumulation in a more distal setting. Coal seams that developed in the lower part of the section have relatively high amounts of detrital macerals, indicative of higher water levels and a higher degree of water circulation within the mires. The common occurrence of red beds in the upper part of the section and the increase of structured macerals, including fusinite, suggest somewhat drier conditions during peat accumulation. Petrographic compositions of underlying coals of the South Bar Formation (Gardiner and Tracy seams) indicate deposition in a somewhat more proximal setting than most coals from the Sydney Mines Formation, reflecting the overall retrogradational development of the Morien Group.
Coal rank and burial history of Cretaceous – Tertiary strata in the Grande Cache and Hinton areas, Alberta, Canada: implications for fossil fuel exploration
Authors: Kalkreuth W. , McMechan M.
Published: July 2009

The present study discusses coal rank and burial histories for Cretaceous–Tertiary coal measures and thermal maturity of associated source rocks. Coal rank ranges from subbituminous to semianthracite. Coalification maps for selected coal zones indicate a broad coalification maximum east of the deformed belt. In the Pocahontas, Brûlé, and Hinton areas, rank levels appear to be elevated locally due to geothermal anomalies. Thermal modelling indicates that the westward decrease of coal rank in Lower Cretaceous strata is related to a westward decrease in the duration of burial beneath Maastrichtian–Eocene foreland-basin deposits. Upper Cretaceous – Tertiary strata were subjected to relatively low geothermal gradients (< 20 °C/km), whereas Lower Cretaceous strata were exposed to much higher gradients (up to 46 °C/km). Tectonic loading in the foothills had only a minor impact on coalification. At Obed Marsh (Alberta Syncline) thermal modelling suggests that deformation in the thrust belt continued for at least a few million years beyond the 60 Ma age recently suggested by fission-track analysis to indicate the end of Laramide deformation. Petroleum source rock intervals of the study area are currently at various stages of thermal maturity (oil generation window to dry gas zone). Coal seams in the Upper Cretaceous – Tertiary coal measures at and near surface have rank levels suitable for combustion, whereas seams in the Lower Cretaceous coal measures are high-quality metallurgical coals. East of the deformed belt the coal measures occur at depths that at the present time are uneconomic for production.
40Ar/39Ar phlogopite and U – Pb perovskite dating of lamprophyre dykes from the eastern Lake Superior region: evidence for a 1.14 Ga magmatic precursor to Midcontinent Rift volcanism
Authors: Queen M. , Hanes J. A. , Archibald D. A. , Farrar E. , Heaman L. M.
Published: July 2009

Thin lamprophyre dykes are abundant in the vicinity of the ca. 1.1 Ga Midcontinent Rift System and the late Archean – Early Proterozoic Kapuskasing Uplift in the Canadian Shield northeast of Lake Superior. However, the relationship between these dykes and spatially associated alkalic-carbonatite complexes has been unclear. To ascertain the temporal relationship between the two, we have determined, by 40Ar/39Ar and U–Pb dating, precise emplacement ages for six lamprophyre dykes from the region. The [Formula: see text] Ma U–Pb date for perovskite from the western Marathon and Wawa areas is indistinguishable from the 1144 ± 7 Ma 40Ar/39Ar date for phlogopite from the eastern Kapuskasing Uplift, and it is concluded that these dykes are part of a regional 1.14 Ga swarm that extends over 300 km. These dykes were therefore emplaced some 35 Ma prior to the 1109 Ma commencement of Midcontinent Rift volcanism and coeval alkaline-complex activity, but essentially simultaneously with emplacement of the 1141 ± 2 Ma Abitibi diabase dyke swarm. It is suggested that these widespread 1144 Ma lamprophyre dykes and the Abitibi diabase dykes represent the first magmatic response of initiation of the Midcontinent rifting event, and were precursors to the main rift magmatism at 1109 Ma.
Effects of symbiotic bacteria and tree chemistry on the growth and reproduction of bark beetle fungal symbionts
Authors: Adams A.S. , Currie C.R. , Cardoza Y. , Klepzig K.D. , Raffa K.F.
Published: July 2009

Bark beetles are associated with diverse assemblages of microorganisms, many of which affect their interactions with host plants and natural enemies. We tested how bacterial associates of three bark beetles with various types of host relationships affect growth and reproduction of their symbiotic fungi. Fungi were exposed to volatiles from bacteria in an arena that imposed physical separation but shared airspace. We also exposed fungi to vapors of the host compound, α-pinene, and to combinations of bacterial volatiles and α-pinene. Bacterial volatiles commonly stimulated growth of Leptographium procerum (W.B. Kendr.) M.J. Wingf. and Grosmannia clavigera (Rob.-Jeffr. & R.W. Davidson) Zipfel, Z.W. de Beer & Wingf., which are symbiotic fungi of Dendroctonus valens LeConte and Dendroctonus ponderosae Hopkins, respectively. They less commonly stimulated growth of Ophiostoma ips (Rumbold) Nannf., which is associated with Ips grandicollis Eichhoff. Some bacteria inhibited L. procerum, Ophiostoma montium (Rumbold) von Arx (another associate of D. ponderosae), and O. ips. Bacteria greatly stimulated spore production of symbionts of D. valens and D. ponderosae. α-Pinene strongly affected some of these relationships, causing amplification, reduction, or reversal of the interactions among the bacteria and fungi. Our results show that some bacteria associated with bark beetles directly affect fungal symbionts and interact with tree chemistry to affect fungal growth and sporulation. The strongest effects were induced by bacteria associated with beetles adapted to attacking living trees with vigorous defenses, and on fungal reproductive structures.
Tree growth at stand and individual scales in two dual-species mixture experiments in southern Washington State, USA
Authors: Erickson Heather E. , Harrington Constance A. , Marshall David D.
Published: July 2009

Planting with mixtures of tree species rather than single species is often considered during reforestation because of the potential increased productivity and other benefits. We examined tree growth at the stand and individual tree scales in two experiments contrasting monocultures with a 1:1 mixture of tree species: (1) Douglas-fir ( Pseudotsuga menziesii (Mirb.) Franco) with a conifer of similar shade tolerance (western white pine ( Pinus monticola Dougl. ex D. Don)) and (2) Douglas-fir with a more shade-tolerant conifer (western hemlock ( Tsuga heterophylla (Raf.) Sarg.)). There was no effect of mixture on growth or yield in the Douglas-fir – western white pine combination. In the Douglas-fir – western hemlock combination, yields in the mixture equaled those in Douglas-fir stands because of the enhanced performance of Douglas-fir in the mixture. For Douglas-fir, the height/diameter (h/d) ratio was significantly less in mixture, suggesting reduced competition for light when grown with western hemlock. In contrast, the h/d ratio for western hemlock was significantly greater in mixture, suggesting increased competition for light when grown with Douglas-fir. Neighborhood analyses showed that tree growth was directly related to initial size and inversely related to relative neighbor size and that the h/d ratio was positively related to relative neighbor size. In general, the size of a neighboring tree influenced growth more than species identity. Relationships between h/d ratios and growth rates suggest that growth differences between Douglas-fir and western hemlock in mixture will eventually increase.
Developing resilient ponderosa pine forests with mechanical thinning and prescribed fire in central Oregon's pumice region
Authors: Busse Matt D. , Cochran P.H. , Hopkins William E. , Johnson William H. , Riegel Gregg M. , Fiddler Gary O. , Ratcliff Alice W. , Shestak Carol J.
Published: July 2009

Thinning and prescribed burning are common management practices for reducing fuel buildup in ponderosa pine forests. However, it is not well understood if their combined use is required to lower wildfire risk and to help restore natural ecological function. We compared 16 treatment combinations of thinning, prescribed fire, and slash retention for two decades across a site quality gradient of second-growth pine stands, measuring changes in forest vegetation growth, structure, and composition. Thinning alone doubled the diameter growth increment of ponderosa pine, moderately stimulated shrub production, and resulted in lower tree mortality compared with unthinned plots. In contrast, repeated fire alone did not substantially alter stand structure or increase tree vigor, herbaceous production, or plant diversity. The combined use of thinning and repeated burning reduced shrub cover, yet produced no changes in herbaceous production, plant diversity, stand structure, or tree vigor compared with thin-only treatments. Additional findings identified (1) inconsequential effects of thinning residues on site productivity, (2) the need for multiple entries of prescribed fire if the abatement of shrubs is required, (3) the ineffectiveness of repeated burning to stimulate plant growth, and (4) that the thinning treatment served as an effective surrogate to fire for managing central Oregon forest vegetation.
Fire regimes of the piñon–juniper woodlands of Big Bend National Park and the Davis Mountains, west Texas, USA
Authors: Poulos H.M. , Gatewood R.G. , Camp A.E.
Published: July 2009

While piñon woodlands cover much of arid North America, surprisingly little is known about the role of fire in maintaining piñon forest structure and species composition. The lack of region-specific fire regime data for piñon–juniper woodlands presents a roadblock to managers striving to implement process-based management. This study characterized piñon–juniper fire regimes and forest stand dynamics in Big Bend National Park (BIBE) and the Davis Mountains Preserve of the Nature Conservancy (DMTNC) in west Texas. Mean fire return intervals were 36.5 and 11.2 years for BIBE and DMTNC, respectively. Point fire return intervals were 150 years at BIBE and 75 years at DMTNC. Tree regeneration in west Texas piñon–juniper woodlands occurred historically during favorable climatic conditions following fire years. The presence of multiple fire scars on our fire-scar samples and the multicohort stands of piñon suggested that low intensity fires were common. This study represents one of the few fire-scar-based fire regime studies for piñon–juniper woodlands. Our results differ from other studies in less topographically dissected landscapes that have identified stand-replacing fire as the dominant fire regime for piñon–juniper woodlands. This suggests that mixed-severity fire regimes are typical across southwestern piñon forests, and that topography is an important influence on fire frequency and intensity.
Ontogenetic strategy shift in sapling architecture of Fagus crenata in the dense understorey vegetation of canopy gaps created by selective cutting
Authors: Yagi Takanobu
Published: July 2009

Ontogenetic architectural variation is a key aspect of the light foraging of saplings under canopy gaps, where the interactions with the surrounding understorey plants are intense and change as saplings grow. Therefore, relationships between the allometry of 58 Fagus saplings (15–184 cm tall) and both the surrounding vegetation and light environment were investigated in the dense understorey of canopy gaps. The light available to the saplings exhibited a positive exponential relationship to their height, and at a given sapling height, it was inversely related to the height of the surrounding understorey. The slenderness of the saplings' stems increased as their height increased, and their crown architecture shifted from horizontally spread monolayer to vertically extended multilayer forms, indicating an ontogenetic strategy shift from shade tolerance to shade avoidance. These changes in sapling architecture were independent of the height of the surrounding understorey and, therefore, light availability, although the length of their current-year shoots (reflecting the rate of architectural development) was inversely related to the surrounding understorey height. Thus, ontogenetic architectural variation in Fagus saplings probably has the character of a developmentally programmed growth trajectory preadjusted to the most likely environments; the surrounding environments mainly affect the rate at which saplings move along this trajectory.
LATTICE BOLTZMANN SIMULATION OF THE MOTION OF SPHERICAL PARTICLES IN STEADY POISEUILLE FLOW
Authors: YI H. H. , FAN L. J. , CHEN Y. Y.
Published: July 2009

A technique, based on the stress-integration method, for the evaluation of hydrodynamic forces on solid boundaries is proposed to simulate the solid-fluid flow systems in three dimensions in lattice Boltzmann simulations. The accuracy of the scheme is demonstrated by simulating the sphere migrating in a pressure-driven Newtonian fluid flow in a cylindrical tube. The numerical simulation results recover the Segré–Silberberg effect. Using this scheme, we investigate the behavior of a pair of spheres in a tube Poiseuille flow. Oscillatory states are observed for two spheres with different radii placed on opposite sides. The simulation results show that the present model is an effective and efficient direct numerical simulation method for simulating particle motions in fluid flows at finite Reynolds numbers in three dimensions.
MOUNTAIN TRAIL FORMATION AND THE ACTIVE WALKER MODEL
Authors: GILKS S. J. , HAGUE J. P.
Published: July 2009

We extend the active walker model to address the formation of paths on gradients, which have been observed to have a zigzag form. Our extension includes a new rule, which prohibits direct descent or ascent on steep inclines, simulating aversion to falling. Further augmentation of the model stops walkers from changing direction very rapidly as that would likely lead to a fall. The extended model predicts paths with qualitatively similar forms to the observed trails, but only if the terms suppressing sudden direction changes are included. The need to include terms into the model that stop rapid direction change when simulating mountain trails indicates that a similar rule should also be included in the standard active walker model.
UNITARY OPERATORS, ENTANGLEMENT, AND GRAM–SCHMIDT ORTHOGONALIZATION
Authors: HARDY YORICK , STEEB WILLI-HANS
Published: July 2009

We consider finite-dimensional Hilbert spaces [Formula: see text] with [Formula: see text] with n ≥ 2 and unitary operators. In particular, we consider the case n = 2m, where m ≥ 2 in order to study entanglement of states in these Hilbert spaces. Two normalized states ψ and ϕ in these Hilbert spaces [Formula: see text] are connected by a unitary transformation (n×n unitary matrices), i.e. ψ = Uϕ, where U is a unitary operator UU* = I. Given the normalized states ψ and ϕ, we provide an algorithm to find this unitary operator U for finite-dimensional Hilbert spaces. The construction is based on a modified Gram–Schmidt orthonormalization technique. A number of applications important in quantum computing are given. Symbolic C++ is used to give a computer algebra implementation in C++.
EXACT DYNAMICAL EIGHTFOLD WAY BARYON SPECTRUM AND CONFINEMENT IN STRONGLY COUPLED LATTICE QCD
Authors: FARIA DA VEIGA PAULO A. , O'CARROLL MICHAEL
Published: July 2009

We obtain from the quark–gluon dynamics the eightfold way baryon spectrum exactly in an imaginary time functional integral formulation of 3+1 lattice QCD with Wilson's action in the strong coupling regime (small hopping parameter 0 < κ ≪ 1 and much smaller plaquette coupling [Formula: see text]). The model has SU(3)c local gauge and global SU(3)f flavor symmetries. A decoupling of the hyperplane method naturally unveils the form of the baryon composite fields. In the subspace of the physical Hilbert space of vectors with an odd number of quarks, the baryons are associated with isolated dispersion curves in the energy–momentum spectrum. Spectral representations are derived for the two-baryon correlations, which allow us to detect the energy–momentum spectrum and particles as complex momentum space singularities. The spin 1/2 octet and spin 3/2 decuplet baryons have asymptotic mass -3ln κ and for each baryon there is an antibaryon with identical spectral properties. An auxiliary function method is used to obtain convergent expansions for the masses after subtracting the singular part -3ln κ. The nonsingular part of the mass is analytic in κ and β, i.e. the expansions are controlled to all orders. For β = 0, all the masses have the form M = -3ln κ - 3κ3/4 + κ6r(κ), with r(κ) real analytic. Although we have no Lorentz symmetry in our lattice model, we show that there is a partial restoration of the continuous rotational symmetry at zero spatial momentum, which implies that for all members of the octet (decuplet) r(κ) is the same. So, there is no mass splitting within the octet and within the decuplet. However, there is an octet–decuplet mass difference of [Formula: see text] at β = 0; the splitting persists for β ≠ 0. We also obtain the (anti)baryon dispersion curves which admit the representation [Formula: see text], where [Formula: see text] and [Formula: see text] is of [Formula: see text]. For the octet, [Formula: see text] is jointly analytic in κ and in each pj, for small [Formula: see text]. A new local symmetry, which we call spin flip, is used to establish constraints for the matrix-valued two-baryon correlation and show that all the octet dispersion curves are the same and that the four decuplet dispersion curves are pairwise-identical and depend only on the modulus of the spin z-component. Using a correlation subtraction method we show that the spectrum generated by the baryon and antibaryon fields is the only spectrum, in the odd quark subspace of physical states, up to near the baryon–meson threshold of ≈ -5ln κ. Combining this result with a similar result for the mesons, with mass ≈ -2ln κ, shows that the only spectrum in the entire space of states, up to near the two-meson threshold of ≈ -4ln κ, is generated by the eightfold way hadrons. Hence, for 0 < κ ≪ β ≪ 1, we have shown confinement up to near this threshold.
THOUGHTS ON THE AREA THEOREM
Authors: PARK MU-IN
Published: July 2009

Hawking's area theorem can be understood from a quasistationary process in which a black hole accretes positive energy matter, independent of the details of the gravity action. I use this process to study the dynamics of the inner as well as the outer horizons for various black holes which include the recently discovered exotic black holes and three-dimensional black holes in higher derivative gravities as well as the usual Banados–Teitelboim–Zanelli (BTZ) black hole and the Kerr black hole in four dimensions. I find that the area for the inner horizon "can decrease," rather than increase, with the quasistationary process. However, I find that the area for the outer horizon "never decrease" such as the usual area theorem still works in our examples, though this is quite nontrivial in general. I also find that the recently proposed new entropy formulae for the above mentioned, recently discovered black holes satisfy the second law of thermodynamics.
MULTIPLE D2-BRANE ACTION FROM M2-BRANES
Authors: LI TIANJUN , LIU YAN , XIE DAN
Published: July 2009

We study the detailed derivation of the multiple D2-brane effective action from multiple M2-branes in the Bagger–Lambert–Gustavsson (BLG) theory and the Aharony–Bergman–Jafferis–Maldacena (ABJM) theory by employing the novel Higgs mechanism. We show explicitly that the high-order F3 and F4 terms are commutator terms, and conjecture that all the high-order terms are commutator terms. Because the commutator terms can be treated as the covariant derivative terms, these high-order terms do not contribute to the multiple D2-brane effective action. Inspired by the derivation of a single D2-brane from a M2-brane, we consider the curved M2-branes and introduce an auxiliary field. Integrating out the auxiliary field, we indeed obtain the correct high-order F4 terms in the D2-brane effective action from the BLG theory and the ABJM theory with SU(2) × SU(2) gauge symmetry, but we cannot obtain the correct high-order F4 terms from the ABJM theory with U(N) × U(N) and SU(N) × SU(N) gauge symmetries for N > 2. We also briefly comment on the (gauged) BF membrane theory.
Chapter 10 Baryon Spectrum
Authors: Bian Jian-Ming , Bytev Vladimir , Chen Ying , Jin Hong-Ying , Jin Shan , Qin Hu , Shen Xiao-Yan , Wu Ning , Xu Guo-Fa , Zhang Zhen-Xia , Zhao Qiang , Zhemchugov Alexey , Zheng Han-Qing , Zhu Shi-Lin , Zou Bing-Song
Published: July 2009

The following sections are included:

Baryons as qqq States

Outstanding Problems in Baryon Spectroscopy

Baryon Spectroscopy at BESI and BESII

Prospects for Baryon Spectroscopy at BESIII
Chapter 18 Hadronic Decays
Authors: Chen Yu-Qi , He Zhi-Guo , Mo Xiaohu , Wang Ping , Yuan Changzheng , Barnes T. , Rong G. , Zhang D.H. , Ma H.L. , Ping Ronggang
Published: July 2009

The following sections are included:

Light Hadron Decay

P-Wave hc Decay

ρ - π Puzzle

Open-Flavor Decays

ψ(3770) Non-[Formula: see text] Decays

Baryonic Decays

ψ(3770) and ψ(4415) Decays to [Formula: see text]
Chapter 19 Rare and Forbidden Charmonium Decays
Authors: Li Haibo , Ma Jianping , Zhang Xinmin
Published: July 2009

The following sections are included:

Weak Decays of Charmonium

Search for the Invisible Decays of Quarkonium

Search for C or P Violating Processes in J/ψ Decays

Lepton Flavor Violating Processes in Decays of J/ψ
Appendix A Statistics in HEP Data Analysis
Authors: Zhu Yong-Sheng
Published: July 2009

The following sections are included:

Parameter Estimation

Interval Estimation, Confidence Interval and Upper Limit

Tests of Hypotheses

Bibliography
UNIFORM L2-STABILITY ESTIMATES FOR THE RELATIVISTIC BOLTZMANN EQUATION
Authors: HA SEUNG-YEAL , LEE HO , YANG XIONGFENG , YUN SEOK-BAE
Published: July 2009

In this paper, we derive an a prioriL2-stability estimate for classical solutions to the relativistic Boltzmann equation, when the initial datum is a small perturbation of a global relativistic Maxwellian. For the stability estimate, we use the dissipative property of the linearized collision operator and a Strichartz type estimate for classical solutions. As a direct application of our stability estimates, we establish that classical solutions in Glassey–Strauss and Hsiao–Yu's frameworks satisfy a uniform L2-stability estimate.