bluuebunny/crossref_metadata_2025 huggingface dataset:
Comment on “The Silicate-Mediated Formose Reaction: Bottom-Up Synthesis of Sugar Silicates”
Authors: Kim Hyo-Joong , Benner Steven A.
Published: August 2010

Lambert
et al
. (Reports, 19 February 2010, p. 984) reported that silicate ions catalyze the formation and stabilization of four- and six-carbon sugars from simple sugars, suggesting a possible prebiotic pathway for the synthesis of biologically important sugars. Here, we show that silicate has minimal impact in these respects, especially when compared to borate minerals.
Evidence of Recent Thrust Faulting on the Moon Revealed by the Lunar Reconnaissance Orbiter Camera
Authors: Watters Thomas R. , Robinson Mark S. , Beyer Ross A. , Banks Maria E. , Bell James F. , Pritchard Matthew E. , Hiesinger Harald , van der Bogert Carolyn H. , Thomas Peter C. , Turtle Elizabeth P. , Williams Nathan R.
Published: August 2010

Lunar Lobate Scarps Revealed

Lunar lobate scarps are relatively small-scale landforms that are thought to be formed by tectonic thrust faulting. Previously, lunar lobate scarps could only be identified clearly in high-resolution Apollo Panoramic Camera images confined to the lunar equatorial zone. Now, an analysis by

Watters
et al.

(p.
936
) of images returned by the Lunar Reconnaissance Orbiter Camera reveals 14 previously unknown lobate scarps and shows that lunar lobate scarps may be globally distributed. Their appearance suggests that lunar scarps are relatively young landforms (less than 1 Ga), possibly formed during a recent episode of global lunar radial contraction.
Chloroplasts Divide by Contraction of a Bundle of Nanofilaments Consisting of Polyglucan
Authors: Yoshida Yamato , Kuroiwa Haruko , Misumi Osami , Yoshida Masaki , Ohnuma Mio , Fujiwara Takayuki , Yagisawa Fumi , Hirooka Shunsuke , Imoto Yuuta , Matsushita Kazunobu , Kawano Shigeyuki , Kuroiwa Tsuneyoshi
Published: August 2010

Chloroplast Division Machinery

The machinery for photosynthesis, which captures the Sun's energy to generate carbohydrates, generally resides in subcellular chloroplasts of plant cells. Chloroplasts must divide as the plant cell divides, but to do so requires their own plastid dividing machinery.

Yoshida
et al.

(p.
949
: see the cover) have now analyzed the plastid dividing machinery of the single-celled alga
Cyanidioschyzon merolae
, whose cells each contain a single chloroplast. The plastid dividing machinery is made up of polysaccharide chains and the proteins that make them, which together generate a ring that constricts to physically divide the chloroplast.
Loss of DNA Replication Control Is a Potent Inducer of Gene Amplification
Authors: Green Brian M. , Finn Kenneth J. , Li Joachim J.
Published: August 2010

The Pitfalls of Re-Replication

The cell has several layers of regulation to ensure that the genome is replicated once and only once during cell division, presumably to avoid the formation of duplicated sequences, which have the potential to recombine and compromise genome stability. In agreement with this idea,

Green
et al.

(p.
943
; see the Perspective by

Kaochar
et al.

) now show that re-replication of a marked yeast replication origin causes a significant increase in copy number variation in the region encompassing the origin. The observed duplications range in size from 135 to 470 kilobases and are almost all tandemly arrayed in a head-to-tail orientation. The duplicated regions are bounded by Ty repetitive elements and arise from nonallelic homologous recombination between the re-replicated repetitive elements.
Partnerships for STEM Education
Authors: Foster K. M. , Bergin K. B. , McKenna A. F. , Millard D. L. , Perez L. C. , Prival J. T. , Rainey D. Y. , Sevian H. M. , VanderPutten E. A. , Hamos J. E.
Published: August 2010

Schoolteachers and higher-education faculty can benefit one another to improve teaching and student learning.
Females Use Multiple Mating and Genetically Loaded Sperm Competition to Target Compatible Genes
Authors: Pryke Sarah R. , Rollins Lee A. , Griffith Simon C.
Published: August 2010

Sauce for the Goose?

Extra-pair copulations benefit males by increasing their potential number of offspring. However, whether they have adaptive significance for females has long been debated.

Pryke
et al.

(p.
964
), provided female finches four different scenarios to test when extra-pair copulations occurred and measured the paternity of the resulting offspring. By varying the potential fathers from a supposedly adaptive, compatible male through a neutral context, to a supposedly maladaptive scenario, females biased paternity to the extra-pair male when his contribution was adaptive and away from the extra-pair male when his contribution was maladaptive. Thus, despite bias in copulation frequency in favor of the social pair, cryptic female choice may show a fertilization bias toward compatible genes.
Directing Light Emission from Quantum Dots
Authors: Giessen Harald , Lippitz Markus
Published: August 2010

The photon emission from a semiconductor quantum dot directed by a nanoscale gold antenna could be used in quantum optics.
After Outcry, Oil Data Inches Into the Open
Authors: Schenkman Lauren
Published: August 2010

In a largely unexpected and welcome move, BP has revised its contracts to remove restrictions on discussing or publishing any data collected on their dime for up to 3 years. And the National Oceanic and Atmospheric Administration is also relaxing its own restrictions on publishing assessment data.
One-Two Punch Elevates Rats to the Knockout Ranks
Authors: Normile Dennis
Published: August 2010

Last week, a group reported online in
Nature
about having successfully adapted to the rat the most widely used mouse knockout technique. This complements a different method for deleting rat genes described last year in
Science
.
Effect of Revaccination Using Different Schemes among Adults with Low or Undetectable Anti-HBs Titers after Hepatitis B Virus Vaccination
Authors: Lin Chao-Shuang , Xie Shi-Bin , Liu Jing , Zhao Zhi-Xin , Chong Yu-Tian , Gao Zhi-Liang
Published: August 2010

Our objective was to investigate the effect of various reimmunization schemes for hepatitis B in adults with low or undetectable anti-HBs titers. Over 2 years, 10 μg of
Saccharomyces cerevisiae
-recombinant hepatitis B virus (HBV) vaccine (synthesized in China) was used in at least one standardized scheme to immunize 2,310 healthy male and nonpregnant female adults. Of these, 240 subjects tested negative for hepatitis B markers. These 240 subjects were equally divided into 4 groups. The first group, designated Engerix-40, was revaccinated with 40 μg Engerix-B; the second, Engerix-20, was revaccinated with 20 μg Engerix-B; the third, Chinese-20, was revaccinated with 20 μg Chinese-made yeast-recombinant vaccine; and the last group, Chinese-10, was revaccinated with 10 μg Chinese-made yeast-recombinant vaccine. Blood samples were collected before and 1, 2, 8, and 12 months after the first injection. The anti-HBs-positive conversion rates of the Engerix-40, Engerix-20, and Chinese-20 groups were higher than that of the Chinese-10 group (
P
< 0.01). Over time, the anti-HBs conversion rate increased in all groups, but values were significantly different from those for the other groups only in the Chinese-10 group (
P
< 0.001). The anti-HBs geometric mean titers (GMTs) of the Engerix-40, Engerix-20, and Chinese-20 groups were higher than in the Chinese-10 group (
P
< 0.05). Increased doses raise and maintain anti-HBs titers in subjects with low or undetectable titers after HBV vaccination.
Identification ofMycobacterium tuberculosisAntigens of High Serodiagnostic Value
Authors: Ireton Gregory C. , Greenwald Rena , Liang Hong , Esfandiari Javan , Lyashchenko Konstantin P. , Reed Steven G.
Published: August 2010

Tuberculosis (TB) is a chronic infectious disease caused byMycobacterium tuberculosis, with several million new cases detected each year. Current methods of diagnosis are time-consuming and/or expensive or have a low level of accuracy. Therefore, new diagnostics are urgently needed to address the global tuberculosis burden and to improve control programs. Serological assays remain attractive for use in resource-limited settings because they are simple, rapid, and inexpensive and offer the possibility of detecting cases often missed by routine sputum smear microscopy. The aim of this study was to identifyM. tuberculosisseroreactive antigens from a panel of 103 recombinant proteins selected as diagnostic candidates. Initial library screening by protein array analysis and enzyme-linked immunosorbent assay (ELISA) identified 42 antigens with serodiagnostic potential. Among these, 25 were novel proteins. The reactive antigens demonstrated various individual sensitivities, ranging from 12% to 78% (specificities, 76 to 100%). When the antigens were analyzed in combinations, up to 93% of antibody responders could be identified among the TB patients. Selected seroreactive proteins were used to design 3 new polyepitope fusion proteins. Characterization of these antigens by multiantigen print immunoassay (MAPIA) revealed that the vast majority of the TB patients (90%) produced antibody responses. The results confirmed that due to the remarkable variation in immune recognition patterns, an optimal multiantigen cocktail should be designed to cover the heterogeneity of antibody responses and thus achieve the highest possible test sensitivity.
Characterization ofErysipelothrixSpecies Isolates from Clinically Affected Pigs, Environmental Samples, and Vaccine Strains from Six Recent Swine Erysipelas Outbreaks in the United States
Authors: Bender J. S. , Shen H. G. , Irwin C. K. , Schwartz K. J. , Opriessnig T.
Published: August 2010

The aim of this study was to characterizeErysipelothrixsp. isolates from clinically affected pigs and their environment and compare them to theErysipelothrixsp. vaccines used at the sites. Samples were collected during swine erysipelas outbreaks in vaccinated pigs in six Midwest United States swine operations from 2007 to 2009. Pig tissue samples were collected from 1 to 3 pigs from each site. Environmental samples (manure, feed, central-line water, oral fluids, and swabs collected from walls, feed lines, air inlets, exhaust fans, and nipple drinkers) and live vaccine samples were collected following the isolation ofErysipelothrixspp. from clinically affected pigs. AllErysipelothrixsp. isolates obtained were further characterized by serotyping. Selected isolates were further characterized by PCR assays for genotype (E. rhusiopathiae,E. tonsillarum,Erysipelothrixsp. strain 1, andErysipelothrixsp. strain 2) and surface protective antigen (spa) type (A, B1, B2, and C). All 26 isolates obtained from affected pigs wereE. rhusiopathiae, specifically, serotypes 1a, 1b, 2, and 21. From environmental samples, 56 isolates were obtained and 52/56 wereE. rhusiopathiae(serotypes 1a, 1b, 2, 6, 9, 12, and 21), 3/56 wereErysipelothrixsp. strain 1 (serotypes 13 and untypeable), and one was a novel species designatedErysipelothrixsp. strain 3 (serotype untypeable). Four of six vaccines used at the sites were commercially available products and contained liveE. rhusiopathiaeserotype 1a. Of the remaining two vaccines, one was an autogenous live vaccine and contained liveE. rhusiopathiaeserotype 2 and one was a commercially produced inactivated vaccine and was described by the manufacturer to contain serotype 2 antigen. AllE. rhusiopathiaeisolates were positive forspaA. AllErysipelothrixsp. strain 1 isolates and the novelErysipelothrixsp. strain 3 isolate were negative for all currently knownspatypes (A, B1, B2, and C). These results indicate thatErysipelothrixspp. can be isolated from the environment of clinically affected pigs; however, the identified serotypes in pigs differ from those in the environment at the selected sites. At one of the six affected sites, the vaccine strain and the isolates from clinically affected pigs were of homologous serotype; however, vaccinal and clinical isolates were of heterologous serotype at the remaining five sites, suggesting that reevaluation of vaccine efficacy using recent field strains may be warranted.
Multiplex Blood PCR in Combination with Blood Cultures for Improvement of Microbiological Documentation of Infection in Febrile Neutropenia
Authors: Lamoth F. , Jaton K. , Prod'hom G. , Senn L. , Bille J. , Calandra T. , Marchetti O.
Published: August 2010

The frequent lack of microbiological documentation of infection by blood cultures (BC) has a major impact on clinical management of febrile neutropenic patients, especially in cases of unexplained persistent fever. We assessed the diagnostic utility of the LightCycler SeptiFast test (SF), a multiplex blood PCR, in febrile neutropenia. Blood for BC and SF was drawn at the onset of fever and every 3 days of persistent fever. SF results were compared with those of BC, clinical documentation of infection, and standard clinical, radiological, and microbiological criteria for invasive fungal infections (IFI). A total of 141 febrile neutropenic episodes in 86 hematological patients were studied: 44 (31%) microbiologically and 49 (35%) clinically documented infections and 48 (34%) unexplained fevers. At the onset of fever, BC detected 44 microorganisms in 35/141 (25%) episodes. Together, BC and SF identified 78 microorganisms in 61/141 (43%) episodes (
P
= 0.002 versus BC or SF alone): 12 were detected by BC and SF, 32 by BC only, and 34 by SF only. In 19/52 (37%) episodes of persistent fever, SF detected 28 new microorganisms (7 Gram-positive bacterial species, 15 Gram-negative bacterial species, and 6 fungal species [89% with a clinically documented site of infection]) whereas BC detected only 4 pathogens (8%) (
P
= 0.001). While BC did not detect fungi, SF identified 5
Candida
spp. and 1
Aspergillus
sp. in 5/7 probable or possible cases of IFI. Using SeptiFast PCR combined with blood cultures improves microbiological documentation in febrile neutropenia, especially when fever persists and invasive fungal infection is suspected. Technical adjustments may enhance the efficiency of this new molecular tool in this specific setting.
Electronic-Nose Technology Using Sputum Samples in Diagnosis of Patients with Tuberculosis
Authors: Kolk Arend , Hoelscher Michael , Maboko Leonard , Jung Jutta , Kuijper Sjoukje , Cauchi Michael , Bessant Conrad , van Beers Stella , Dutta Ritaban , Gibson Tim , Reither Klaus
Published: August 2010

We investigated the potential of two different electronic noses (EN; code named “Rob” and “Walter”) to differentiate between sputum headspace samples from tuberculosis (TB) patients and non-TB patients. Only samples from Ziehl-Neelsen stain (ZN)- and
Mycobacterium tuberculosis
culture-positive (TBPOS) sputum samples and ZN- and culture-negative (TBNEG) samples were used for headspace analysis; with EN Rob, we used 284 samples from TB suspects (56 TBPOS and 228 TBNEG samples), and with EN Walter, we used 323 samples from TB suspects (80 TBPOS and 243 TBNEG samples). The best results were obtained using advanced data extraction and linear discriminant function analysis, resulting in a sensitivity of 68%, a specificity of 69%, and an accuracy of 69% for EN Rob; for EN Walter, the results were 75%, 67%, and 69%, respectively. Further research is still required to improve the sensitivity and specificity by choosing more selective sensors and type of sampling technique.
Critical Stages of Extracting DNA from
Aspergillus fumigatus
in Whole-Blood Specimens
Authors: White P. Lewis , Perry Michael D. , Loeffler Juergen , Melchers Willem , Klingspor Lena , Bretagne Stephane , McCulloch Elaine , Cuenca-Estrella Manuel , Finnstrom Niklas , Donnelly J. Peter , Barnes Rosemary A.
Published: August 2010

A standardized protocol for extracting DNA from
Aspergillus fumigatus
has been proposed by the European
Aspergillus
PCR Initiative (EAPCRI). Using meta-regression analysis, the EAPCRI showed certain stages of the process to be critical to providing a satisfactory analytical sensitivity. The study investigated each step of the EAPCRI protocol by elimination and monitored the influence on
Aspergillus
PCR performance.
Apoptosis of Hepatitis B Virus-Infected Hepatocytes Prevents Release of Infectious Virus
Authors: Arzberger Silke , Hösel Marianna , Protzer Ulrike
Published: August 2010

Apoptosis of infected cells is critically involved in antiviral defense. Apoptosis, however, may also support the release and spread of viruses. Although the elimination of infected hepatocytes is required to combat hepatitis B virus (HBV) infection, it is still unknown which consequences hepatocyte apoptosis has for the virus and whether or not it is advantageous to the virus. To study this, we designed a cell culture model consisting of both HBV-producing cell lines and primary human hepatocytes serving as an infection model. We showed that the release of mature, enveloped virions was 80% to 90% reduced 24 h after the induction of apoptosis in HBV-replicating hepatoma cells or HBV-infected hepatocytes. Importantly, HBV particles released from apoptotic hepatocytes were immature and nonenveloped and proved not to be infectious. We found an inverse correlation between the strength of an apoptotic stimulus and the infectivity of the virus particles released: the more potent the apoptotic stimulus, the higher the ratio of nonenveloped capsids to virions and the lower their infectivity. Furthermore, we demonstrated that HBV replication and, particularly, the expression of the HBx protein transcribed from the viral genome during replication do not sensitize cells to apoptosis. Our data clearly reject the hypothesis that the apoptosis of infected hepatocytes facilitates the propagation of HBV. Rather, these data indicate that HBV needs to prevent the apoptosis of its host hepatocyte to ensure the release of infectious progeny and, thus, virus spread in the liver.
Murine Cytomegalovirus Perturbs Endosomal Trafficking of Major Histocompatibility Complex Class I Molecules in the Early Phase of Infection
Authors: Tomaš Maja Ilić , Kučić Natalia , Mahmutefendić Hana , Blagojević Gordana , Lučin Pero
Published: August 2010

Murine cytomegalovirus (MCMV) functions interfere with protein trafficking in the secretory pathway. In this report we used Δm138-MCMV, a recombinant virus with a deleted viral Fc receptor, to demonstrate that MCMV also perturbs endosomal trafficking in the early phase of infection. This perturbation had a striking impact on cell surface-resident major histocompatibility complex class I (MHC-I) molecules due to the complementary effect of MCMV immunoevasins, which block their egress from the secretory pathway. In infected cells, constitutively endocytosed cell surface-resident MHC-I molecules were arrested and retained in early endosomal antigen 1 (EEA1)-positive and lysobisphosphatidic acid (LBPA)-negative perinuclear endosomes together with clathrin-dependent cargo (transferrin receptor, Lamp1, and epidermal growth factor receptor). Their progression from these endosomes into recycling and degradative routes was inhibited. This arrest was associated with a reduction of the intracellular content of Rab7 and Rab11, small GTPases that are essential for the maturation of recycling and endolysosomal domains of early endosomes. The reduced recycling of MHC-I in Δm138-MCMV-infected cells was accompanied by their accelerated loss from the cell surface. The MCMV function that affects cell surface-resident MHC-I was activated in later stages of the early phase of viral replication, after the expression of known immunoevasins. MCMV without the three immunoevasins (the m04, m06, and m152 proteins) encoded a function that affects endosomal trafficking. This function, however, was not sufficient to reduce the cell surface expression of MHC-I in the absence of the transport block in the secretory pathway.
The F Gene of the Osaka-2 Strain of Measles Virus Derived from a Case of Subacute Sclerosing Panencephalitis Is a Major Determinant of Neurovirulence
Authors: Ayata Minoru , Takeuchi Kaoru , Takeda Makoto , Ohgimoto Shinji , Kato Seiichi , Sharma Luna Bhatta , Tanaka Miyuu , Kuwamura Mitsuru , Ishida Hiroshi , Ogura Hisashi
Published: August 2010

Measles virus (MV) is the causative agent for acute measles and subacute sclerosing panencephalitis (SSPE). Although numerous mutations have been found in the MV genome of SSPE strains, the mutations responsible for the neurovirulence have not been determined. We previously reported that the SSPE Osaka-2 strain but not the wild-type strains of MV induced acute encephalopathy when they were inoculated intracerebrally into 3-week-old hamsters. The recombinant MV system was adapted for the current study to identify the gene(s) responsible for neurovirulence in our hamster model. Recombinant viruses that contained envelope-associated genes from the Osaka-2 strain were generated on the IC323 wild-type MV background. The recombinant virus containing the M gene alone did not induce neurological disease, whereas the H gene partially contributed to neurovirulence. In sharp contrast, the recombinant virus containing the F gene alone induced lethal encephalopathy. This phenotype was related to the ability of the F protein to induce syncytium formation in Vero cells. Further study indicated that a single T461I substitution in the F protein was sufficient to transform the nonneuropathogenic wild-type MV into a lethal virus for hamsters.
Epstein-Barr Virus Nuclear Antigen 1 Hijacks the Host Kinase CK2 To Disrupt PML Nuclear Bodies
Authors: Sivachandran Nirojini , Cao Jennifer Yinuo , Frappier Lori
Published: August 2010

Latent Epstein-Barr virus (EBV) infection is an important causative factor in the development of several cancers, including nasopharyngeal carcinoma (NPC). The one EBV protein expressed in the nucleus of NPC cells, EBNA1, has been shown to disrupt promyelocitic leukemia (PML) nuclear bodies (NBs) by inducing the degradation of PML proteins, leading to impaired DNA repair and increased cell survival. Although EBNA1-mediated PML disruption is likely to be an important factor in the development of NPC, little is known about its mechanism. We now show that an interaction between EBNA1 and the host CK2 kinase is crucial for EBNA1 to disrupt PML bodies and degrade PML proteins. EBNA1 increases the association of CK2 with PML proteins, thereby increasing the phosphorylation of PML proteins by CK2, a modification that is known to trigger the polyubiquitylation and degradation of PML. The interaction between EBNA1 and CK2 is direct and occurs through the β regulatory subunit of CK2 and EBNA1 amino acids 387 to 394. The binding of EBNA1 to the host ubiquitin specific protease USP7 has also been shown to be important for EBNA1-mediated PML disruption. We show that EBNA1 also increases the occupancy of USP7 at PML NBs and that CK2 and USP7 bind independently and simultaneously to EBNA1 to form a ternary complex. The combined results indicate that EBNA1 usurps two independent cellular pathways to trigger the loss of PML NBs.
Dissociation of Paramyxovirus Interferon Evasion Activities: Universal and Virus-Specific Requirements for Conserved V Protein Amino Acids in MDA5 Interference
Authors: Ramachandran Aparna , Horvath Curt M.
Published: August 2010

The V protein of the paramyxovirus subfamily
Paramyxovirinae
is an important virulence factor that can interfere with host innate immunity by inactivating the cytosolic pathogen recognition receptor MDA5. This interference is a result of a protein-protein interaction between the highly conserved carboxyl-terminal domain of the V protein and the helicase domain of MDA5. The V protein C-terminal domain (CTD) is an evolutionarily conserved 49- to 68-amino-acid region that coordinates two zinc atoms per protein chain. Site-directed mutagenesis of conserved residues in the V protein CTD has revealed both universal and virus-specific requirements for zinc coordination in MDA5 engagement and has also identified other conserved residues as critical for MDA5 interaction and interference. Mutation of these residues produces V proteins that are specifically defective for MDA5 interference and not impaired in targeting STAT1 for proteasomal degradation via the VDC ubiquitin ligase complex. Results demonstrate that mutation of conserved charged residues in the V proteins of Nipah virus, measles virus, and mumps virus also abolishes MDA5 interaction. These findings clearly define molecular determinants for MDA5 inhibition by the paramyxovirus V proteins.
Salvage Neuroform stent-assisted coiling for recurrent giant aneurysm after waffle-cone treatment
Authors: Hauck Erik F , Natarajan Sabareesh K , Hopkins L Nelson , Levy Elad I , Siddiqui Adnan H
Published: August 2010

We report a case of aneurysm progression after waffle-cone treatment. A patient in their seventies presented with headaches. Four years earlier, this individual had undergone waffle-cone treatment of a giant ruptured left ophthalmic aneurysm. Angiography demonstrated aneurysm growth. A second stent was deployed through the initially placed stent to recreate the aneurysm neck and to provide support for stent-assisted coiling. The residual aneurysm was coiled with good outcome.
Modeling and forecasting pine sawtimber stumpage prices in the US South by various time series models
Authors: Mei Bin , Clutter Michael , Harris Thomas
Published: August 2010

Among the three timberland return drivers (biological growth, timber price, and land price), timber price remains the most unpredictable. It affects not only periodic dividends from timber sales but also timber production strategies embedded in timberland management. Using various time series techniques, this study aimed to model and forecast real pine sawtimber stumpage prices in 12 southern timber regions in the United States. Under the discrete-time framework, the univariate autoregressive integrated moving average model was established as a benchmark, whereas other multivariate time series methods were applied in comparison. Under the continuous-time framework, both the geometric Brownian motion and the Ornstein–Uhlenbeck process were fitted. The results revealed that (i) the vector autoregressive model forecasted more accurately in the 1-year period by the mean absolute percentage error criterion, (ii) seven out of the 12 southern timber regions played dominant roles in the long-run equilibrium, and (iii) conditional variances and covariances from the bivariate generalized autoregressive conditional heteroscedasticity model well captured market risks.
The serpentine syndrome below ground: ectomycorrhizas and hypogeous fungi associated with conifers
Authors: Gladish Sandra , Frank Jonathan , Southworth Darlene
Published: August 2010

Serpentine soils select for unique plant communities, often with sparse vegetation. Mycorrhizal fungi mediate the interaction between plants and soils, yet little is known about the mycorrhizal fungi of serpentine-tolerant plants. Ectomycorrhizas and hypogeous fungal sporocarps were sampled on paired serpentine and nonserpentine soils in southwestern Oregon. We hypothesized that conifers on serpentine soils would have fewer species of mycorrhizal fungi, a distinct assemblage of ectomycorrhizal fungi, and fewer hypogeous sporocarps with less species richness. Sporocarps were sampled and soil cores collected around pines on serpentine and nonserpentine soils. Conifers on serpentine and nonserpentine soils hosted overlapping communities of ectomycorrhizal fungi, as characterized by nonmetric multidimensional scaling. From soil cores, we categorized 27 species by morphotype, of which 18 were identified by DNA. Fewer hypogeous sporocarps with less taxonomic richness were collected on serpentine soils. The lack of indicator species of mycorrhizal fungi and the greater variability among samples on serpentine soils suggest that soil composition does not determine the mycorrhizal community. The sparseness of host vegetation may limit the ability of fungi to grow from tree to tree and may increase the reliance on spore dispersal, thus creating a more varied pattern of mycorrhizal communities.
Determining the main and interactive effect of age and clone on wood density, microfibril angle, and modulus of elasticity for Pinus radiata
Authors: Watt Michael S. , Sorensson Charles , Cown Dave J. , Dungey Heidi S. , Evans Robert
Published: August 2010

Detailed radial measurements of wood properties, taken at breast height, were obtained from control pollinated seedlings and a selection of 13 year old radiata pine ( Pinus radiata D. Don) clones. Using these data the key objectives of this study were to determine (i) the magnitude of mean clonal variation in modulus of elasticity (MOE) and properties affecting MOE (density and microfibril angle (MFA)) and (ii) whether there is a significant age × clone interaction for these traits. All wood properties were significantly affected by the main and interactive effects of age and clone. There was a relatively linear increase in both MOE and density with tree age, while MFA declined linearly with tree age. Values of density and MOE diverged between the clonal extremes from age 3 to age 12. After diverging markedly up to age 6, differences in MFA between clonal extremes remained relatively constant to age 12. At age 12, values for density, MFA, and MOE varied between clonal extremes by, respectively, 194 kg·m–3 (465–659 kg·m–3), 11.3° (9.6–20.9°), and 11.2 GPa (10.4–21.6 GPa). The seedling material had a relatively intermediate ranking, across the age range, for all traits considered.
Intra-annual density fluctuations of Pinus pinaster are a record of climatic changes in the western Mediterranean region
Authors: Vieira Joana , Campelo Filipe , Nabais Cristina
Published: August 2010

Climate projections for the Mediterranean area estimate a decline in total precipitation, warmer temperatures, and a higher frequency of extreme drought events. It is important to understand how trees respond to these climatic changes and which wood anatomical structures best document the trees’ response to those changes. The present work investigates the climatic signal of tree-ring width, latewood width, and the frequency of intra-annual density fluctuations (IADFs) during the last 100 years for Pinus pinaster Aiton growing in the western Mediterranean region. Based on meteorological data, it was observed that since the 1950s, average annual temperature and autumn and winter precipitation increased. Tree-ring width and latewood width of P. pinaster were positively correlated with winter and summer precipitation and negatively correlated with spring and summer temperatures. The frequency of latewood IADFs showed a positive and time-stable correlation with September and October precipitation. However, after the 1970s, the frequency of IADFs also became correlated with climatic conditions later in the year, specifically with the temperatures of November and December, probably because of the recent climate changes. IADFs chronologies, besides being very useful to reconstruct autumn precipitation, can add new climatic information to ring-width chronologies.
An inventory-based approach for modeling single-tree storm damage — experiences with the winter storm of 1999 in southwestern Germany
Authors: Schmidt Matthias , Hanewinkel Marc , Kändler Gerald , Kublin Edgar , Kohnle Ulrich
Published: August 2010

Based on individual tree damage data dating back to the gale “Lothar” (winter 1999) in Baden-Württemberg, Germany, a statistical model was developed to estimate the risk of storm damage for individual trees. The data were compiled from the National German Forest Inventory. The model attempts to separate the effects of tree-specific variables, topography, site conditions and flow field related effects on damage probability. The crucial problem of missing information on the actual flow field parameters was solved by applying a generalized additive model that enables the simultaneous fit of a spatial trend function. The geographical location of risk hotspots as predicted by the model correspond well to the actual distribution pattern of storm damage as assessed by the forest service. Tree height proved to be one of the most important factors affecting the level of damage, while height to diameter at breast height ratio influences damage probability to a much lesser extent. The Norway spruce ( Picea abies (L.) Karst.) group has the highest potential to be damaged followed by the silver fir ( Abies alba Miller) – Douglas-fir ( Pseudotsuga menziesii (Mirb.) Franco) group and the Scots pine ( Pinus sylvestris L.) – larches ( Larix spp.) group. Predicted probabilities for deciduous trees are generally lower than those of conifers. West- to south-exposed locations bear a considerably higher damage risk and waterlogged soils show an increased predicted probability compared with slightly or not waterlogged soils.
Development of a model describing modulus of elasticity across environmental and stand density gradients in plantation-grown Pinus radiata within New Zealand
Authors: Watt Michael S. , Zoric Branislav
Published: August 2010

Modulus of elasticity (E) is an important property in plantation grown softwoods that describes resistance of timber to deformation under load and is a key criterion in machine stress grading. This paper presents an accurate (R2 = 0.96) site-level model of E for radiata pine ( Pinus radiata D. Don) that is applicable across a wide range of tree ages and broad environmental gradients and sensitive to a wide variation in stand density. In the final model, E increased sigmoidally with age and increased linearly with both stem slenderness (height/diameter at 1.4 m) and mean minimum autumn air temperature. For a given age, the model shows stem slenderness to be the main determinant of environmental variation in E, with variation in E ranging approximately 10 GPa across the range in slenderness. Given the simple formulation, this model could be readily used by managers to gain greater understanding of how they can manipulate stands to achieve desired end-use products and maximize crop value. Further research should extend the developed framework so that it can be used to account for intratree, intertree, and clonal variation in E.
Optimal white spruce breeding zones for Ontario under current and future climates
Authors: Thomson Ashley M. , Crowe Kevin A. , Parker William H.
Published: August 2010

Optimal breeding zones were developed for white spruce ( Picea glauca (Moench) Voss) in Ontario under present and future climate conditions to examine potential shifts due to climate change. These zones were developed by (i) determining a set of candidate breeding zones based on the relationship between measured performance variables and climate and (ii) employing a decision support model to select subsets of breeding zones that maximize geographic coverage subject to a constraint on the maximum number of zones. Current optimal breeding zones were based on 1961–1990 climate normals, and future breeding zones were based on three general circulation model (CGCM2, HADCM3, and CSIRO) predictions of 2041–2070 climate. Based on a maximum adaptive distance of 2.0 least significant difference values between sites within zones, 14 zones were required to cover the Ontario range of white spruce for the 1961–1990 data. Compared with breeding zones of other boreal conifers, current optimal breeding zones for white spruce were quite large, spanning up to 3° latitude and 10°–12° longitude and indicating large distances of effective seed transfer. Of the three general circulation models used to simulate future climate, HADCM3 B2 and CGCM2 B2 predicted 2041–2070 breeding zones that largely coincide with 1961–1990 zones. In contrast, CSIRO B2 indicated much narrower 2041–2070 breeding zones.
Metabolic power budgeting and adaptive strategies in zoology: examples from scallops and fishThe present review is one of a series of occasional review articles that have been invited by the Editors and will feature the broad range of disciplines and expertise represented in our Editorial Advisory Board.
Authors: Guderley Helga , Pörtner Hans Otto
Published: August 2010

Evolutionary explanations of the adaptive value of animal characteristics are often expressed in energetic terms, but unless they are accompanied by demonstrations of limited energy availability, they remain speculative. In this review, we argue that metabolic power budgeting provides easily testable mechanisms through which energetically efficient attributes could become adaptive. Given each organism’s maximal aerobic (and metabolic) capacity, available metabolic power (energy use per unit time) is limited and must be partitioned between different processes. This leads to compromises among the major fitness functions of growth, locomotor activity, and reproductive investment. As examples of such conflicts, we examine the compromise among growth, reproduction, and predator avoidance in scallops, as well as the means whereby thermal limitations on oxygen uptake reflect the geographical distribution limits and associated energetic trade-offs of temperate zone and polar fishes. These examples show several means whereby the budgeting of aerobic power is implicated in the major fitness trade-offs faced by animals.
Dynamic feeding habits: efficiency of frugivory in a nectarivorous bat
Authors: Becker Nina I. , Rothenwöhrer Christoph , Tschapka Marco
Published: August 2010

Fluctuations in food availability may result in drastic changes of main dietary habits in some animals despite the lack of adaptations to alternative food types. We compared feeding efficiency between the nectarivorous bat Glossophaga commissarisi Gardner, 1962 (Phyllostomidae) that switches during nectar shortages to frugivory and the specialized frugivore Carollia brevicauda (Schinz, 1821) in a combination of behavioural experiments and HPLC (high performance liquid chromatography) analysis of fruit and faecal samples. We assessed feeding duration and employment of different bite types while animals were feeding on fruits from their natural diet. Although both bat species employed predominantly mechanically more efficient bite types, feeding efficiency (mg of fruit ingested/s) was significantly lower in G. commissarisi. Our study showed that the two bat species employed distinctly different handling and feeding strategies when feeding on the same fruits. “Frugivorous” G. commissarisi consume mostly fruit juices, but fruit anatomy seems to influence feeding efficiency. In an ecological context, the trophic shift of G. commissarisi from nectar to fruits may have implications for plant species that coevolved with bats, as well as for niche partitioning of coexisting bat species. In a more general context, our study highlights a dynamic nature of feeding niches, which might be rather common for animals living in habitats with changes in resource availability.
Reproduction management affects breeding ecology and reproduction costs in feral urban Pigeons (Columba livia)
Authors: Jacquin Lisa , Cazelles Bernard , Prévot-Julliard Anne-Caroline , Leboucher Gérard , Gasparini Julien
Published: August 2010

Reproduction management of natural popsulations can have long-term consequences that have to be examined to avoid unwanted side effects. Management policies of urban Pigeons ( Columba livia Gmelin, 1789) include the set up of public Pigeon houses that aim at limiting hatching rate by egg removal. However, long-term consequences of this management method on the ecology of this species are still unknown. In this study we examined how egg removal affected egg-laying cycles of Pigeons by using a powerful method of time-series analysis, the wavelet method. We compared egg-laying cycles in Pigeon houses exposed to different management treatments and found that egg-laying cycles were shorter (4 weeks) in Pigeon houses with egg removal compared with control Pigeon houses without egg removal (11 weeks), suggesting that Pigeons respond to egg-removal pressure by multiplying reproduction attempts. Furthermore, we found that egg quality, an important index of female condition, was negatively affected by egg removal. This result suggests that the observed increase of egg production can lead to an increase of reproductive physiological costs and to a decrease of female condition. This study raises issues about potential consequences of such a management procedure on parasite resistance and health status of urban bird populations.
Effects of diet quality on growth pattern, serum oxidative status, and corticosterone in Pigeons (Columba livia)
Authors: Costantini David
Published: August 2010

Oxidative stress has been suggested to be affected by the growth and developmental period of animals, hence it may play an important role in the trade-off between growth and self-maintenance. In this study, I analysed the effects of two different diet regimes (high-quality diet, HQD; low-quality diet, LQD) on growth pattern, three components of the serum oxidative status (hydroperoxides, antioxidant capacity, and thiols), and serum corticosterone in nestling Pigeons ( Columba livia Gmelin, 1789). The growth pattern was similar in the first week of life, after which HQD nestlings grew faster than LQD nestlings. Although there were no differences in serum corticosterone or thiol concentrations, serum oxidative damage increased faster over the nestling phase in HQD than LQD chicks. Serum antioxidant capacity remained stable over time in LQD nestlings and increased in HQD nestlings. This study provides evidence that different growth rates (induced in the absence of any physiological stress or prior nutritional deprivation) are accompanied by different serum oxidative statuses.
A NOTE ON THE (ANTI-)BRST INVARIANT LAGRANGIAN DENSITIES FOR THE FREE ABELIAN 2-FORM GAUGE THEORY
Authors: GUPTA SAURABH , MALIK R. P.
Published: August 2010

We show that the previously known off-shell nilpotent [Formula: see text] and absolutely anticommuting (sb sab + sab sb = 0) Becchi–Rouet–Stora–Tyutin (BRST) transformations (sb) and anti-BRST transformations (sab) are the symmetry transformations of the appropriate Lagrangian densities of a four (3+1)-dimensional (4D) free Abelian 2-form gauge theory which do not explicitly incorporate a very specific constrained field condition through a Lagrange multiplier 4D vector field. The above condition, which is the analogue of the Curci–Ferrari restriction of the non-Abelian 1-form gauge theory, emerges from the Euler–Lagrange equations of motion of our present theory and ensures the absolute anticommutativity of the transformations s(a)b. Thus, the coupled Lagrangian densities, proposed in our present investigation, are aesthetically more appealing and more economical.
REMOVING BLACK HOLE SINGULARITIES WITH NONLINEAR ELECTRODYNAMICS
Authors: CORDA CHRISTIAN , CUESTA HERMAN J. MOSQUERA
Published: August 2010

We propose a way to remove black hole singularities by using a particular nonlinear electrodynamics Lagrangian that has been recently used in various astrophysics and cosmological frameworks. In particular, we adapt the cosmological analysis discussed in a previous work to the black hole physics. Such analysis will be improved by applying the Oppenheimer–Volkoff equation to the black hole case. At the end, fixed the radius of the star, the final density depends only on the introduced quintessential density term ργ and on the mass.
HIGGS MECHANISM FOR GRAVITONS
Authors: ODA ICHIRO
Published: August 2010

Just like the vector gauge bosons in the gauge theories, it is now known that gravitons acquire mass in the process of spontaneous symmetry breaking of diffeomorphisms through the condensation of scalar fields. The point is that we should find the gravitational Higgs mechanism such that it results in massive gravity in a flat Minkowski spacetime without non-unitary propagating modes. This is usually achieved by including higher-derivative terms in scalars and tuning the cosmological constant to be a negative value in a proper way. Recently, a similar but different gravitational Higgs mechanism has been advocated by Chamseddine and Mukhanov where one can relax the negative cosmological constant to zero or positive one. In this work, we investigate why the non-unitary ghost mode decouples from physical Hilbert space in a general spacetime dimension. Moreover, we generalize the model to possess an arbitrary potential and clarify under what conditions the general model exhibits the gravitational Higgs mechanism. By searching for solutions to the conditions, we arrive at two classes of potentials exhibiting gravitational Higgs mechanism. One class includes the model by Chamseddine and Mukhanov in a specific case while the other is a completely new model.
EMERGENT GEOMETRY AND QUANTUM GRAVITY
Authors: YANG HYUN SEOK
Published: August 2010

We explain how quantum gravity can be defined by quantizing spacetime itself. A pinpoint is that the gravitational constant [Formula: see text] whose physical dimension is of (length)2 in natural unit introduces a symplectic structure of spacetime which causes a noncommutative spacetime at the Planck scale L P . The symplectic structure of spacetime M leads to an isomorphism between symplectic geometry (M, ω) and Riemannian geometry (M, g) where the deformations of symplectic structure ω in terms of electromagnetic fields F = dA are transformed into those of Riemannian metric g. This approach for quantum gravity allows a background independent formulation where spacetime as well as matter fields is equally emergent from a universal vacuum of quantum gravity which is thus dubbed as the quantum equivalence principle.
WIRELESS THREE DIMENSIONAL ACCELEROMETER REFLEX QUANTIFICATION DEVICE WITH ARTIFICIAL REFLEX SYSTEM
Authors: LEMOYNE ROBERT , MASTROIANNI TIMOTHY , COROIAN CRISTIAN , GRUNDFEST WARREN
Published: August 2010

Fundamental to the neurological examination is the deep tendon reflex. Two important tendon reflex parameters are response and latency. Response can be quantified by the NINDS Myotatic Reflex Scale; however, controversy exists with respect to the accuracy of the scale. Electrodiagnostic testing may derive parameters, similar to the validity of the reflex latency; however, such tests require highly specialized resources. Attempts have been made to develop quantified reflex devices. Two wireless three-dimensional (3D) accelerometers incorporating MEMS technology have been integrated into a device for quantifying reflex response and latency. The device is tested and evaluated using an artificial reflex system. The reflex quantification device obtained reflex response and latency parameters based on the artificial reflex device, which were bounded by a 98% confidence level with a 2% margin of error about the mean.
Opportunities and challenges to unify workload, power, and cooling management in data centers
Authors: Wang Zhikui , Tolia Niraj , Bash Cullen
Published: August 2010

Independent optimization for workload and power management, and active cooling control have been studied extensively to improve data center energy efficiency. Recently, proposals have started to advocate unified workload, power, and cooling management for further energy savings. In this paper, we study this problem with the objectives of both saving energy and capping power. We present the detailed models derived in our previous work from experiments on an blade enclosure system that can be representative of a data center, discuss the optimization opportunities for coordinated power and cooling management, and the challenges for controller design. We then propose a few design principles and examples for unified workload management, power minimization, and power capping. Our simulation-based evaluation shows that the controllers can cap the total power consumption while maintaining the thermal conditions and improve the overall energy efficiency. We argue that the same opportunities, challenges, and designs are also generally applicable to data center level management.