bluuebunny/crossref_metadata_2025 huggingface dataset:
A Novel Method for Simultaneous and Continuous Determination of Thermal Properties during Phase Transition Applied to Calanus finmarchicus
Authors: Bantle Michael , Eikevik Trygve Magne , Brennvall Jon Eirik
Published: July 2010

Abstract:  The thermal properties of a product are the most important parameters for practical engineering purposes and models in food science. Calanus finmarchicus is currently being examined as a marine resource for uncommon aquatic lipids and proteins. Thermal conductivity, specific heat, enthalpy and density were measured over the temperature range from −40 to +20 °C. The initial freezing point was determined to be −2.3 °C. The thermal properties were recorded continuously on 4 samples using a new method, and the results were compared with predictive models. The accuracy of the new method is demonstrated by different calibration runs. Significant differences in the thermal conductivity of the frozen material were found between the parallel‐series model and the data, whereas the model of Pham and Willix (1989) or the Maxwell–Euken adaption showed better agreement. The measured data for specific heat, enthalpy, and density agreed well with the model.

Practical Application:  The thermal data obtained can be used directly in food engineering and technology applications, for example, in a thin layer model for freezing food for which precise thermal data for each layer are now available, enabling the more accurate prediction of freezing times and temperature profiles. Dimensionless numbers (such as the Biot number) can also be based on measured data with minor deviations compared to more general modeled thermal properties. Future activities will include the generation of a comprehensive database for different products.
Bowel obstruction associated with endoscopic tattooing of the colon with India ink
Authors: Seki Y , Sekimoto M , Noura S , Takemasa I , Ikeda M , Yamamoto H , Doki Y , Mori M
Published: July 2010

During a laparoscopic resection of small colorectal lesions, preoperative endoscopic marking with India ink is useful for identifying the location of the lesion. India ink has been thought to be a safe agent with few adverse effects. We herein report a case who suffered from postoperative abdominal pain resulting in bowel obstruction, due to massive adhesion around the area with India ink. A 61‐year‐old man with early transverse colon cancer underwent a laparoscopy‐assisted transverse colon resection. Prior to the operation, endoscopic tattooing with India ink was performed. At the operation, spillage of India ink into the peritoneal cavity was observed. Many small black spots were thereafter seen on the peritoneum, mesentery and omentum, but neither severe inflammation nor any adhesion was noticed. The operation was performed without any difficulty. Though his immediate postoperative course was uneventful, a bowel obstruction gradually developed from a week postoperatively. Finally, he had to undergo a re‐operation, and was found to have diffuse and massive adhesion around areas with India ink. Especially, severe omental adhesion involved and squeezed the transverse colon. A resection of the omentum with stenotic colon and re‐anastomosis was performed. India ink can cause severe inflammation and adhesion when it accidentally leaks into the peritoneal cavity.
Effect of poly (ethylene oxide)-poly (propylene oxide)-poly (ethylene oxide) micelles on pharmacokinetics and intestinal toxicity of irinotecan hydrochloride: potential involvement of breast cancer resistance protein (ABCG2)
Authors: Guo Shiyan , Zhang Xinxin , Gan Li , Zhu Chunliu , Gan Yong
Published: July 2010

Objectives

Intestinal toxicity and low levels of systemic drug exposure are among the major problems associated with tumour therapy. We have developed poly (ethylene oxide)-poly (propylene oxide)-poly (ethylene oxide) (PEO-PPO-PEO) micelles loaded with irinotecan hydrochloride (CPT-11) hoping to decrease CPT-11-induced intestinal toxicity while increasing its systemic exposure. In addition, we have investigated the potential involvement of breast cancer resistance protein (BCRP) in biliary excretion, pharmacokinetics, and intestinal toxicity of CPT-11.

Methods

PEO-PPO-PEO micelles were prepared using PEO20-PPO70-PEO20 and lecithin. The effect of PEO-PPO-PEO micelles on BCRP-mediated cellular accumulation and transport efflux of CPT-11 was evaluated in MDCKII/BCRP cells. The biliary excretion, intestinal damage, and pharmacokinetic study of CPT-11-loaded PEO-PPO-PEO micelles were investigated in rats.

Key findings

The obtained micelles could effectively inhibit BCRP-mediated CPT-11 efflux in MDCKII/BCRP cells, and significantly decrease the drug biliary excretion in rats. Moreover, intestinal toxicity, assessed by microscopic examination of pathological damage, was ameliorated in rats injected with PEO-PPO-PEO micelles compared with rats injected with CPT-11 alone. Treatment with PEO-PPO-PEO micelles resulted in prolonged circulation time in blood and increased bioavailability of CPT-11 and SN-38 (7-ethyl-10-hydroxycamptothecin).

Conclusions

PEO-PPO-PEO micelles were identified as promising carriers able to reduce intestinal toxicity and increase antitumour therapeutic effect of CPT-11. The study indicated a potential involvement of BCRP in CPT-11 pharmacokinetics and CPT-11-induced intestinal toxicity.
Antineoplastic effect of β-elemene on prostate cancer cells and other types of solid tumour cells
Authors: Li Qingdi Quentin , Wang Gangduo , Huang Furong , Banda Malathi , Reed Eddie
Published: July 2010

Objectives

β-Elemene, a natural compound extracted from over 50 different Chinese medicinal herbs and plants, has been effective in the treatment of hyperplastic and proliferative disorders such as prostatic hypertrophy, hysteromyoma and neoplasms. Our previous studies have demonstrated that β-elemene exhibits strong inhibitory activity in ovarian cancer cells. The aim of the present study was to assess the effect of β-elemene on prostate cancer cells as well as other types of tumour cells and to determine whether the effect of β-elemene on prostate cancer cell death was mediated through the induction of apoptosis.

Methods

The MTT assay was used to evaluate the ability of β-elemene to inhibit cellular proliferation in cancer cells. Cellular apoptosis was assessed by annexin V binding, TUNEL and ELISA-based assays. Caspase activity was measured using a caspases assay kit. The protein levels of Bcl-2, caspases, cytochrome c and poly(ADP-ribose) polymerase (PARP) were analysed by Western blotting.

Key findings

Here, we showed that β-elemene had an antiproliferative effect on androgen-insensitive prostate carcinoma DU145 and PC-3 cells. Treatment with β-elemene also inhibited the growth of brain, breast, cervical, colon and lung carcinoma cells. The effect of β-elemene on cancer cells was dose dependent, with IC50 values ranging from 47 to 95 µg/ml (230–465 µm). TUNEL assay and flow cytometric analysis using annxin V/propidium iodide staining revealed that the percentage of apoptotic prostate cancer cells was increased by β-elemene in a dose- and time-dependent manner. Moreover, β-elemene exposure resulted in a decreased Bcl-2 protein level, increased cytochrome c release, and activated PARP and caspase-3, -7, -9, and -10 in prostate cancer cells.

Conclusions

Overall, these findings suggest that β-elemene exerts broad-spectrum antitumour activity against many types of solid carcinoma and supports a proposal of β-elemene as a new potentially therapeutic drug for castration-resistant prostate cancer and other solid tumours.
Identification of Force Coefficients in a Squeeze Film Damper With a Mechanical Seal: Large Contact Force
Authors: Delgado Adolfo , San Andrés Luis
Published: July 2010

Squeeze film dampers (SFDs) aid to reduce excessive vibration levels due to rotor imbalance and to raise stability thresholds in rotor-bearing systems. SFDs commonly include end seals to increase their damping capability with a lesser lubricant flow. Seals also aid to reduce the occurrence of air ingestion/entrapment that severely reduces the damper forced performance. However, most conventional end seals do not completely eliminate lubricant side leakage, which limits their effectiveness to prevent air ingestion. A novel end seal arrangement incorporates a spring loaded, contacting mechanical seal that effectively prevents lubricant side leakage and air ingestion. The mechanically sealed damper is intended for use in power engines for unmanned aircraft vehicles. The test damper journal is 2.54 cm in length and 12.7 cm in diameter, with a radial clearance of 0.127 mm. Prior literature reports dynamic load tests on the seal-SFD and measurements of orbital motions to characterize the mechanical parameters of both the mechanical seal and squeeze film damper section. The test data to date include damper operation for a single contact load (90 N) closing the mechanical seal. Presently, measurements of damper dynamic load performance are conducted with a larger contact force (260 N). A nonlinear parameter identification method in the frequency domain determines simultaneously the squeeze film damping and inertia coefficients and the seal dry-friction force. The test results show that the system equivalent viscous damping coefficients are twice as large as those obtained earlier with the smaller contact force. On the other hand, as expected, the squeeze film damper coefficients are nearly identical for both test configurations. Predicted squeeze film damping coefficients, from an improved model that includes the flow in the damper feed and discharge grooves, correlate well with the test data for small and moderate orbit radii. The experimental fluid added mass coefficients are in par with the actual mass of the bearing housing and accurately predicted.
A Model for Improved Prediction of Force Coefficients in Grooved Squeeze Film Dampers and Oil Seal Rings
Authors: Delgado Adolfo , San Andrés Luis
Published: July 2010

Squeeze film damper (SFD) designs typically implement supply grooves to ensure adequate lubricant flow into the film lands. Oil seal rings, of land film clearance c, also incorporate short and shallow grooves (length≤30c,depth≤15c) to reduce cross-coupled stiffnesses, thus promoting dynamic stability without a penalty in increased leakage. However, extensive experimental results in the archival literature demonstrate that grooves do not reduce the force coefficients as much as theory predicts. A common assumption is that deep grooves do not influence a damper or oil seal ring forced response. However, unexpected large added mass coefficients, not adequately predicted, appear to be common in many tested SFD and oil seal configurations. In the case of oil seals, experiments demonstrate that circumferential grooves do reduce cross-coupled stiffnesses but to a lesser extent than predictions would otherwise indicate. A linear fluid inertia bulk-flow model for analysis of the forced response of SFDs and oil seal configurations with multiple grooves is advanced. A perturbation analysis for small amplitude journal motions about a centered position yields zeroth and first-order flow equations at each flow region (lands and grooves). At a groove region, a groove effective depth dη, differing from its actual physical value, is derived from qualitative observations of the laminar flow pattern through annular cavities. The boundary conditions at the inlet and exit planes depend on the actual seal or SFD configuration. Integration of the resulting first-order pressure fields on the journal surface yields the force coefficients (stiffness, damping, and inertia). Current model predictions are in excellent agreement with published test force coefficients for a grooved SFD and a grooved oil seal. The results confirm that large added mass coefficients arise from the flow interactions between the feed/discharge grooves and film lands in the test elements. Furthermore, the predictions, benchmarking experimental data, corroborate that short length inner-land grooves in an oil seal do not isolate the pressure fields of adjacent film lands and hence contribute greatly to the forced response of the mechanical element.
On Squeeze Film Damping in Microsystems
Authors: Marrero Victor , Borca-Tasciuc Diana-Andra , Tichy John
Published: July 2010

Classical hydrodynamic lubrication theory has been one of the most successful and widely used theories in all of engineering and applied science. This theory predicts that the force resisting the squeezing of a fluid between two parallel plates is inversely proportional to the cube of the fluid thickness. However, recent reports on liquid squeeze film damping in microsystems appear to indicate that experimentally measured damping force is proportional to the inverse of the fluid thickness to the first power—a large fundamental discrepancy from classical theory. This paper investigates potential limitations of lubrication theory in microsystems by theoretical and computational methods. The governing equations for a Newtonian incompressible fluid are solved subject to two-dimensional, parallel surface squeezing by an open-source computational fluid dynamics program called parallel hierarchic adaptive stabilized transient analysis (PHASTA), and by a classical similarity solution technique. At low convective Reynolds numbers, the damping force is determined as a function of the ratio of a reference film thickness H to a reference direction B along the film. Good agreement with classical lubrication theory is found for aspect ratios H/B as high as 1 despite the fact that lubrication theory requires that this ratio be “small.” A similarity analysis shows that when instantaneous convective Reynolds number is of order 10–100 (a range present in experiment), calculated damping deviates significantly from lubrication theory. This suggests that nonlinearity associated with high Reynolds numbers could explain the experimentally observed discrepancy in damping force. Dynamic analysis of beams undergoing small vibrations in the presence of a liquid medium further supports this finding.
Effect of Thread and Bearing Friction Coefficients on the Self-Loosening of Preloaded Countersunk-Head Bolts Under Periodic Transverse Excitation
Authors: Zaki Amro M. , Nassar Sayed A. , Yang Xianjie
Published: July 2010

A nonlinear mathematical model is developed for studying the self-loosening behavior of preloaded countersunk threaded fasteners that are subjected to cyclic transverse loads. Torque components acting on the bolt are divided into pitch and resistance torque components; the net torque determines whether or not the bolt will rotate loose under the external excitation. The accumulation of the differential amount of loosening rotation increments is converted into the gradual loss of the bolt tension/clamp load. Although the loosening model incorporates several system variables, this study is focused on investigating the effect of thread and bearing friction coefficients on the loosening of fasteners with coarse and fine threads. Model prediction of the self-loosening behavior is experimentally validated.
Feasibility of Gas-Expanded Lubricants for Increased Energy Efficiency in Tilting-Pad Journal Bearings
Authors: Clarens Andres , Younan Amir , Wang Shibo , Allaire Paul
Published: July 2010

Lubricants are necessary in tilting-pad journal bearings to ensure separation between solid surfaces and to dissipate heat. They are also responsible for much of the undesirable power losses that can occur through a bearing. Here, a novel method to reduce power losses in tilting-pad journal bearings is proposed in which the conventional lubricant is substituted by a binary mixture of synthetic lubricant and dissolved CO2. These gas-expanded lubricants (GELs) would be delivered to a reinforced bearing housing capable of withstanding modest pressures less than 10 MPa. For bearings subject to loads that are both variable and predictable, GELs could be used to adjust lubricant properties in real time. High-pressure lubricants, mostly gases, have already been explored in tilting-pad journal bearings as a means to accommodate higher shaft speeds while reducing power losses and eliminating the potential for thermal degradation of the lubricant. These gas-lubricated bearings have intrinsic limitations in terms of bearing size and load capacity. The proposed system would combine the loading capabilities of conventional lubricated bearings with the efficiency of gas-lubricated bearings. The liquid or supercritical CO2 serves as a low-viscosity and completely miscible additive to the lubricant that can be easily removed by purging the gas after releasing the pressure. In this way, the lubricant can be fully recycled, as in conventional systems, while controlling the lubricant properties dynamically by adding liquid or supercritical CO2. Lubricant properties of interest, such as viscosity, can be easily tuned by controlling the pressure inside the bearing housing. Experimental measurements of viscosity for mixtures of polyalkylene glycol (PAG)+CO2 at various compositions demonstrate that significant reductions in mixture viscosity can be achieved with relatively small additions of CO2. The measured parameters are used in a thermoelastohydrodynamic model of tilting-pad journal bearing performance to evaluate the bearing response to GELs. Model estimates of power loss, eccentricity ratio, and pad temperature suggest that bearings would respond quite favorably over a range of speed and preload conditions. Calculated power loss reductions of 20% are observed when compared with both a reference petroleum lubricant and PAG without CO2. Pad temperature is also maintained without significant increases in eccentricity ratio. Both power loss and pad temperature are directly correlated with PAG-CO2 composition, suggesting that these mixtures could be used as “smart” lubricants responsive to system operating conditions.
Self Lubricating Composite Coatings Containing TiC–MnS or WC-MnS Compounds Prepared by the Plasma Transferred Arc (PTA) Technique
Authors: Skarvelis P. , Papadimitriou G. D. , Perraki M.
Published: July 2010

Composite coatings containing manganese sulphide as lubricating addition and enhanced with hard carbide particles (TiC, WC) were synthesized on a plain steel substrate using the plasma transferred arc technique. The coatings are well bonded to the substrate, have a thickness of about 1 mm, and are free of any visual defects. They consist mainly of a martensitic or ferritic matrix enhanced with titanium or tungsten carbides and a dispersion of MnS particles. The tribological properties of the composites are assessed using a pin-on-disk device. Both composites possess self lubricating properties, due to the formation of a thin layer of manganese sulphide on their wear tracks. The corresponding friction coefficients vary between 0.25 and 0.28, compared with 0.50–0.60 obtained from similar hard coatings without MnS addition. The wear rates are of the order of 10−5 mm3/m N and are two orders of magnitude lower than those obtained from the substrate material with MnS addition, but without the presence of hard enhancing particles. The wear regime is mild abrasion due to the combined action of both lubricating (MnS) and hard (TiC or WC) particles.
Could Exercise Metabolomics Pave the Way for Gymnomimetics?
Authors: Burke Megan F. , Dunbar Richard L. , Rader Daniel J.
Published: July 2010

An analysis of metabolites that change in concentration during exercise suggests possibilities for mimicking its beneficial effects.
Robust Stimulation of Humoral and Cellular Immune Responses following Vaccination with Antigen-Loaded β-Glucan Particles
Authors: Huang Haibin , Ostroff Gary R. , Lee Chrono K. , Specht Charles A. , Levitz Stuart M.
Published: July 2010

β-Glucan particles (GPs) are purifiedSaccharomyces cerevisiaecell walls treated so that they are primarily β1,3-d-glucans and free of mannans and proteins. GPs are phagocytosed by dendritic cells (DCs) via the Dectin-1 receptor, and this interaction stimulates proinflammatory cytokine secretion by DCs. As the hollow, porous GP structure allows for high antigen loading, we hypothesized that antigen-loaded GPs could be exploited as a receptor-targeted vaccine delivery system. Ovalbumin (OVA) was electrostatically complexed inside the hollow GP shells (GP-OVA). Incubation of C57BL/6J mouse bone marrow-derived DCs with GP-OVA resulted in phagocytosis, upregulation of maturation markers, and rapid proteolysis of OVA. Compared with free OVA, GP-OVA was >100-fold more potent at stimulating the proliferation of OVA-reactive transgenic CD8+OT-I and CD4+OT-II T cells, as measured byin vitro[3H]thymidine incorporation using DCs as antigen-presenting cells. Next, immune responses in C57BL/6J mice following subcutaneous immunizations with GP-OVA were compared with those in C57BL/6J mice following subcutaneous immunizations with OVA absorbed onto the adjuvant alum (Alum/OVA). Vaccination with GP-OVA stimulated substantially higher antigen-specific CD4+T-cell lymphoproliferative and enzyme-linked immunospot (ELISPOT) responses than that with Alum/OVA. Moreover, the T-cell responses induced by GP-OVA were Th1 biased (determined by gamma interferon [IFN-γ] ELISPOT assay) and Th17 biased (determined by interleukin-17a [IL-17a] ELISPOT assay). Finally, both the GP-OVA and Alum/OVA formulations induced strong secretions of IgG1 subclass anti-OVA antibodies, although only GP-OVA induced secretion of Th1-associated IgG2c antibodies. Thus, the GP-based vaccine platform combines adjuvanticity and antigen delivery to induce strong humoral and Th1- and Th17-biased CD4+T-cell responses.

IMPORTANCEMost licensed vaccines work by promoting protective antibody responses. However, for many infectious diseases, antibody-mediated protection appears to play a relatively minor role, and vaccination has met with limited success. While live-attenuated organisms generally elicit T-cell responses, their use in vaccines is limited by the potential for causing disease. Thus, there is an urgent need for new vaccine platforms that deliver antigens in such a manner as to promote strong T-cell-mediated responses. Here we designed a novel vaccine platform consisting of yeast-derived β-glucan particles (GPs) that combines antigen delivery and adjuvant activity. GPs loaded with the model antigen ovalbumin (OVA) stimulated robust humoral and T-cell responses in mice. In addition, the cellular response was Th1 and Th17 biased. This work has implications for the design of vaccines that stimulate biased T-cell responses as well as for understanding how immunity to fungal pathogens develops.
The immediate effects of foot orthoses on functional performance in individuals with patellofemoral pain syndrome
Authors: Barton C J , Menz H B , Crossley K M
Published: July 2010

Objective

Patellofemoral pain syndrome (PFPS) often results in reduced functional performance. There is growing evidence for the use of foot orthoses to treat this multifactorial condition. In this study, the immediate effects of foot orthoses on functional performance and the association of foot posture and footwear with improvements in function were evaluated.

Methods

Fifty-two individuals with PFPS (18–35 years) were prescribed prefabricated foot orthoses (Vasyli Pro; Vasyli International, Labrador, Australia). Functional outcome measures evaluated included the change in (1) pain and (2) ease of a single-leg squat on a five-point Likert scale, and change in the number of (3) pain-free step downs and (4) single-leg rises from sitting. The association of foot posture using the Foot Posture Index, navicular drop and calcaneal angle relative to subtalar joint neutral; and the footwear motion control properties scale score with improved function were evaluated using Spearman's ρ statistics.

Results

Prefabricated foot orthoses produced significant improvements (p<0.05) for all functional outcome measures. A more pronated foot type and poorer footwear motion control properties were found to be associated with reduced pain during the single-leg squat and improvements in the number of pain-free single-leg rises from sitting when wearing foot orthoses. In addition, a more pronated foot type was also found to be associated with improved ease of completing a single-leg squat when wearing foot orthoses.

Conclusion

Prefabricated foot orthoses provide immediate improvements in functional performance, and these improvements are associated with a more pronated foot type and poorer footwear motion control properties.

Keywords

foot orthoses; patellofemoral pain syndrome; functional performance; knee pain; insoles.
Performance and response to defoliation of Sanguisorba officinalis (Rosaceae) seedlings from mown and successional habitats
Authors: Musche Martin , Settele Josef , Durka Walter
Published: July 2010

In agricultural habitats, selection may favour plants that show a pronounced ability to tolerate stress induced by specific management methods. However, genetic erosion associated with habitat fragmentation may diminish this ability. To assess the role of mowing as a selection pressure and the impact of fragmentation processes on the ability to tolerate foliage loss, we grew 215 plants of the perennial herb Sanguisorba officinalis  L. originating from 16 differently sized populations, located in mown meadows and successional fallows, in a common environment, and measured their performance and response to defoliation. Plants from meadows and fallows neither differed in performance characters nor in their ability to compensate for foliage loss. However, independently from the habitat of origin, populations slightly differed in performance. This variation was not due to differences in population size, plant density, or level of genetic variation, indicating its independence from genetic erosion, which may go along with habitat fragmentation. Rather, these differences between populations appear to be the outcome of unknown selection pressures or random genetic drift. Plants from successional fallows retain their potential to cope with mowing, presumably due to the low generation turnover of the perennial species. Selection by mowing may act over time scales larger than those reflected by the developmental stage of the current habitats.
Characterization of the ATP-translocating properties of the predictedArabidopsis thalianamitochondrial adenine nucleotide translocator 2
Authors: Kharenko Olesya A. , Loewen Michele C.
Published: July 2010

In this study we demonstrate that the predicted Arabidopsis thaliana (L.) Heynh. mitochondrial adenine nucleotide translocator 2 (ANT2) mediates ATP translocation. The demonstration that recombinantly produced ANT2 mediates ATP uptake into proteoliposomes, confirms previous sequence-based identification of the protein as a member of the adenine nucleotide translocator family. Expressed in Saccharomyces cerevisiae with a C-terminal His6 tag, localization was confirmed in yeast membrane extracts. The recombinant protein was solubilized with Triton X-100, enriched by immobilized metal affinity chromatography, and reconstituted into liposomes. Functionality of the reconstituted protein was confirmed by demonstration of pyridoxal 5′-phosphate-sensitive [3H]ATP uptake. Transport assays showed first order kinetic uptake of ATP with an approximate Kmvalue of 15 µmol·L–1. Competition assays indicated that the reconstituted protein had highest specificity for ATP. Overall, these results indicate that Arabidopsis ANT2 is an adenine nucleotide translocator.
Evaluation of genetic variability of wild hops (Humulus lupulus L.) in Canada and the Caucasus region by chemical and molecular methods
Authors: Patzak Josef , Nesvadba Vladimír , Krofta Karel , Henychova Alena , Marzoev Arkady Inalovic , Richards Ken
Published: July 2010

Wild hops ( Humulus lupulus L.) are potential new germplasms to expand the variability of genetic resources for hop breeding. We evaluated Canadian (62 plants) and Caucasian (58 plants) wild hops by their chemical characteristics and with molecular genetic analyses using sequence-tagged site and simple sequence repeat markers, in comparison with European (104 plants) and North American (27 plants) wild hops. The contents of alpha and beta acids varied from 0.36% to 5.11% and from 0.43% to 6.66% in Canadian wild hops, and from 0.85% to 3.65% and from 1.22% to 4.81% in Caucasian wild hops, respectively. The contents of cohumulone and colupulone distinctly differed between European and North American wild hops: the cohumulone level in alpha acids was in the range 46.1%–68.4% among North American wild hops and in the range 13.6%–30.6% among European wild hops. The high content of myrcene and the low contents of humulene, farnesene, and selinenes were typical for wild hops from Canada, in contrast to wild hops from the Caucasus region. We compared the chemical characteristics with molecular genetic data. Chemical characteristics differentiated wild hops into North American and Eurasian groups. Molecular genetic analysis was able to separate Caucasian wild hops from European wild hops. We proved a hop phylogeny by means of wide molecular analysis.
Comparison of gene order ofGIGANTEAloci in yellow-poplar, monocots, and eudicots
Authors: Liang Haiying , Barakat Abdelali , Schlarbaum Scott E. , Mandoli Dina F. , Carlson John E.
Published: July 2010

GIGANTEA plays an important role in the control of circadian rhythms and photoperiodic flowering. The GIGANTEA gene has been studied in various species, but not in basal angiosperms. Moreover, to the best of our knowledge, no study of the genome organization of a basal angiosperm has yet been published. In this study, we sequenced a bacterial artificial chromosome (BAC) harboring GIGANTEA from yellow-poplar ( Liriodendron tulipifera L.) and compared the genomic organization of this gene in yellow-poplar with that in other species from various angiosperm clades. This is the first report on the gene structure and organization of a large contig in any basal angiosperm species. The BAC clone, covering a region of approximately 122 kb from the yellow-poplar genome, was sequenced and assembled by coupling the 454 pyrosequencing technology with ABI capillary sequencing. In addition to GIGANTEA, the gene RPS18.A (encoding ribosomal protein S18.A) was found in this segment of the genome. We found that gene content and order in this region of the yellow-poplar genome were similar to those in the corresponding region in eudicots but not in Oryza sativa and Sorghum bicolor , implying that clustering of the GIGANTEA and RPS18.A genes is ancestral and separation of the genes occurred after the phylogenetic split of monocots from dicots. Phylogenetic analysis of GIGANTEA amino acid sequences placed yellow-poplar closer to eudicots than to monocots. In addition, evidence for transposition and large insertions and duplications was found, suggesting multiple and complex mechanisms of basal angiosperm genome evolution.
Camelina (Camelina sativa(L.) Crantz) as an alternative oilseed: molecular and ecogeographic analyses
Authors: Ghamkhar Kioumars , Croser Janine , Aryamanesh Nader , Campbell Margaret , Kon’kova Nina , Francis Clive
Published: July 2010

Camelina ( Camelina sativa (L.) Crantz) is an oilseed known for its potential as a low-input biofuel feedstock and its high levels of beneficial fatty acids. We investigated the role of geographical origin in genetic variation and fatty acid content, expecting to find significant variability among 53 accessions and a link between ecogeography and both origin and key oil traits. Amplified fragment length polymorphism (AFLP) fingerprinting revealed high levels of diversity within the 53 accessions. Even though sampling was relatively biased towards the Russian–Ukrainian area, this region was identified as a genetic diversity hotspot and possible centre of origin for camelina. The accessions were categorized by principal coordinate analysis using molecular marker data, enabling identification of links between geographical distribution and these categories. The influence of geographic location on four canola oil quality measures in camelina was evaluated using a geographic information system. These measures were (1) more than 30% α-linolenic acid, (2) less than 3% erucic acid, (3) less than 10% saturated fatty acids, and (4) a ratio of α-linolenic to linoleic acid greater than 1. The results clearly confirm that camelina oil quality characteristics are strongly influenced by environmental factors. The unprecedented high genetic diversity in this group of accessions offers an excellent opportunity to investigate valuable genes for successful adaptation of camelina to specific ecogeographical conditions such as drought.
Regional-scale landslide susceptibility mapping using the weights of evidence method: an example applied to linear infrastructure
Authors: Quinn P. E. , Hutchinson D. J. , Diederichs M. S. , Rowe R. K.
Published: July 2010

Large landslides are common in the gently sloping clay plains of the Saint Lawrence Lowlands of eastern Canada. These tend to occur along rivers carved into the marine soils deposited in the former Champlain Sea, which occupied the area roughly 10 000 years ago. This paper presents a landslide susceptibility model, developed at the regional scale using a bivariate statistical method: the weights of evidence method. The analysis considers the association of existing large landslides in a portion of the study area with key terrain features, such as ground elevation, flow accumulation in adjacent streams, soil type, soil thickness, and land use. The resulting model identifies three different levels of susceptibility: low, low to moderate, and moderate to high. These descriptors are related statistically to the probability of encountering existing large landslides within 500 m, 1 or 2 km, respectively. The model is tested along primary railway corridors and isolates 8% of the total length for further consideration of landslide hazard. Reconnaissance level air photo survey results further reduce the length of corridor with elevated susceptibility to 2% of the total length, thus focusing the application of additional resources to a very small proportion of the total inventory.
Large-deformation finite element analysis of pipe penetration and large-amplitude lateral displacement
Authors: Wang Dong , White David J. , Randolph Mark F.
Published: July 2010

Seabed pipelines must be designed to accommodate thermal expansion — which is commonly achieved through controlled lateral buckling — and to resist damage from submarine slides. In both cases, the pipe moves laterally by a significant distance and the overall pipeline response is strongly influenced by the lateral pipe–soil resistance. Here, the process of pipe penetration and lateral displacement is investigated using a large-deformation finite element method, with a softening rate–dependent soil model being incorporated. The calculated soil flow mechanisms, pipe resistances, and trajectories agree well with plasticity solutions and centrifuge test data. It was found that the lateral resistance is strongly influenced by soil heave during penetration and the berm formed ahead of the pipe during lateral displacement. For “light” pipes, the pipe rises to the soil surface and the soil failure mechanism involves sliding at the base of the berm. In contrast, “heavy” pipes dive downwards and a deep shearing zone is mobilized, expanding with continuing lateral movement. The different responses are reconciled by defining an “effective embedment” that includes the effect of the soil berm or wall ahead of the pipe. The relationship between normalized lateral resistance and effective embedment is well fitted using a power law.
A novel approach for the improvement of ethanol fermentation by Saccharomyces cerevisiae
Authors: Hou Lihua , Cao Xiaohong , Wang Chunling
Published: July 2010

Fermentation properties under the control of multiple genes are difficult to alter with traditional methods in Saccharomyces cerevisiae . Here, a novel genome engineering approach is developed to improve ethanol production in very high gravity fermentation with 300 g/L glucose as the carbon source. This strategy involved constructing aneuploid strains on the base of tetraploid cells. The tetraploid strain was constructed by using the plasmid YCplac33-GHK, which harbored the HO gene encoding the site-specific Ho endonucleases. The aneuploid strain, WT4-M, was selected and screened after the tetraploid cells were treated with methyl benzimidazole-2-yl-carbamate to induce loss of mitotic chromosomes. It was found that aneuploid strain WT4-M not only exhibited an increase in ethanol production and osmotic and thermal tolerance, but also an improvement in the sugar–ethanol conversion rate. Notably, WT4-M provided up to 9.8% improvement in ethanol production compared with the control strain. The results demonstrated that the strategy of aneuploidy was valuable for creating yeast strains with better fermentation characteristics.
Comparison of integron-linked antibiotic resistance genes in strains ofSalmonellaspp. isolated from swine in Chile in 2005 and 2008
Authors: Lapierre Lisette , San Martín Betty , Araya-Jordán Carolina , Borie Consuelo
Published: July 2010

Salmonella spp. isolates obtained from healthy swine in 2008 were analyzed for antibiotic resistance phenotypes and genotypes. The resistance profiles of the 2008 isolates were compared with those of a Salmonella collection isolated from the same geographical area in 2005. The 2008 isolates consisted of strains that were 97% oxytetracycline resistant, 33.3% amoxicillin resistant, 31.8% amoxicillin- plus clavulanic acid resistant, 27.5% trimethoprim–sulfamethoxazole resistant, 17.3% streptomycin resistant, and 7.2% enrofloxacin–ciprofloxacin resistant. The presence of integrons and resistance genes and their topological association in resistant strains was assessed by PCR. The prevalence of class 1 integrons was the highest, at 46.2%, while class 2 integrons were present in 17.9% of the isolates. In strains that harboured class 1 integrons, we identified 3 different gene cassette arrangements; a single class 2 integron arrangement of dfrA1–sat1–aadA1 was found. Comparison of these results with data obtained from the 2005 isolates showed that Salmonella strains resistant to amoxicillin and amoxicillin plus clavulanic acid had clearly emerged over the span of 3 years, along with an increase in the prevalence of class 1 integrons and the acquisition of new gene cassette arrangements. These findings highlight the need for continual monitoring of regional isolates to establish more efficient vigilance programs that can address variations in resistance over short periods of time within the same geographical area.
Acute effects of endothelin receptor antagonists on hepatic hemodynamics of cirrhotic and noncirrhotic ratsThis article is one of a selection of papers published in the two-part special issue entitled 20 Years of Endothelin Research.
Authors: Cavasin Maria A. , Semus Hillary , Pitts Kelly , Peng Yanyu , Sandoval Jennifer , Chapo Joseph , Plato Craig F.
Published: July 2010

Hepatic and circulating endothelin-1 (ET-1) are increased in patients with cirrhosis and in cirrhotic animals. However, the distinct roles of ET receptor subtypes ETAand ETBin cirrhosis and portal hypertension (PHT) have not been clearly elucidated. Thus, we studied the effects of selective ET-1 antagonists (ETA-ant or ETB-ant) and nonselective ET-1 antagonist (ETA/B-ant) on hepatic hemodynamics in cirrhotic rats. Liver fibrosis and PHT were induced by complete bile duct ligation (BDL) in rats. Two weeks after BDL or sham surgery, hemodynamic responses were measured during intraportal infusion of incremental doses of the following ET-ants: (i) BQ-123, (ii) BQ-788, and (iii) bosentan. After equilibration with vehicle, doses of ET-ants were infused for 30 min periods, and steady-state systemic and hepatic hemodynamics, portal venous pressure (PVP), and hepatic blood flow (HBF) were measured. BDL induced significant PHT and elevated concentrations of plasma ET-1 compared with sham. ETA-ant decreased PVP of cirrhotic rats but had no effect on sham, whereas ETB-ant increased PVP in sham but had no effect in BDL. Nonselective ETA/B-ant decreased PVP of BDL similarly to ETA-ant. Both ETA-ant and ETB-ant decreased local HBF, whereas a nonselective antagonist did not change HBF in sham; however no significant changes were observed in HBF of BDL rats with any of the antagonists. These findings suggest ETAactivation contributes to PHT in cirrhotic rats, whereas ETB-mediated portal depressor effects are attenuated in cirrhotic rats compared with noncirrhotic rats.
Selective in vivo antagonism of endothelin receptors in transforming growth factor-β1 transgenic mice that mimic the vascular pathology of Alzheimer’s diseaseThis article is one of a selection of papers published in the two-part special issue entitled 20 Years of Endothelin Research.
Authors: Papadopoulos Panayiota , Ongali Brice , Hamel Edith
Published: July 2010

Increased levels of transforming growth factor-β1(TGF-β1) induce a vascular pathology that shares similarities with that seen in Alzheimer’s disease, and which possibly contributes to the cognitive decline. In aged transgenic mice that overexpress TGF-β1(TGF mice), we previously found reduced dilatory function and selectively impaired endothelin-1 (ET-1)-induced contraction. Here we studied the effects of chronic treatments with selective ETA(ABT-627) or ETB(A-192621) receptor antagonist on cerebrovascular reactivity, cerebral perfusion, or memory performance. The dilatory deficit of TGF mice was not improved by either treatment, but both ET-1 contraction and basal nitric oxide (NO) production were distinctly altered. Although ABT-627 was devoid of any effect in TGF mice, it virtually abolished the ET-1-induced contraction and NO release in wild-type (WT) littermates. In contrast, A-192621 only acted upon TGF mice with full recovery of ET-1 contraction and baseline NO synthesis. TGF mice, treated or not, had no cognitive deficit in the Morris water maze, nor did ABT-627-treated WT controls despite severely impaired vasoreactivity. These findings confirm that ETAreceptors primarily mediate the ET-1-induced contraction. Further, they suggest that ETBreceptors play a detrimental role in conditions of increased TGF-β1and that vascular dysfunction does not inevitably lead to cognitive deficit.
Combination therapy of zibotentan with cisplatinum and paclitaxel is an effective regimen for epithelial ovarian cancerThis article is one of a selection of papers published in the two-part special issue entitled 20 Years of Endothelin Research.
Authors: Rosanò Laura , Cianfrocca Roberta , Spinella Francesca , Di Castro Valeriana , Natali Pier Giorgio , Bagnato Anna
Published: July 2010

In human ovarian carcinoma, the endothelin-1 (ET-1) / endothelin A receptor (ETAR) axis is overexpressed, correlating with tumor grade. Moreover, ETAR activation by ET-1 affects cell proliferation, survival, angiogenesis, and invasion. ETAR blockade with zibotentan (ZD4054), a specific ETAR antagonist, significantly inhibits ovarian cancer growth in vitro and in vivo, underscoring the relevance of this pathway as a target for cancer therapy. Since clinical trial results have defined the combination of platinum and taxane as the standard of care in the management of ovarian cancer, here we explored the therapeutic efficacy of the integration of zibotentan with cytotoxic drugs having different modes of action. We found that the combination of zibotentan with cisplatinum as well as zibotentan with paclitaxel was more effective at inhibiting ovarian cancer HEY cell proliferation induced by endogenous ET-1 than were the single agents alone. However, a significantly enhanced efficacy was observed when we combined zibotentan, cisplatinum, and paclitaxel. Accordingly, in HEY xenografts the coadministration of zibotentan with cisplatinum enhanced the efficacy of the cytotoxic drug alone in controlling tumor growth, associated with reduction in proliferation index and microvessel density. Remarkably, the combination of zibotentan with both cisplatinum and paclitaxel was very effective in inhibiting tumor growth, neovascularization, and cell proliferation, representing a preclinical endpoint to guide combination therapy in clinical trials.
FERMI LIQUID MODEL OF RADIATION INDUCED MAGNETORESISTANCE OSCILLATIONS IN GaAs/AlxGa1-xAs HETEROSTRUCTURE TWO-DIMENSIONAL ELECTRON SYSTEM
Authors: TOYODA TADASHI
Published: July 2010

The magnetoresistance oscillation in GaAs / Al x Ga 1-x As heterostructures induced by millimeterwave radiation recently observed by Zudov et al.1 is theoretically reproduced by introducing a model based on the finite temperature Fermi liquid theory of DC conductivity and the electron reservoir hypothesis. The obtained oscillation patterns show excellent agreement with the experimental result by Zudov et al. and are independent of the polarization of the radiation field in accordance with the experimental observation by Smet et al.30
F-CENTER IMPACT ON PHOTOELECTROCHEMICAL PROPERTIES IN HEMATITE
Authors: STASHANS ARVIDS , RIVERA RICHARD
Published: July 2010

Structural and optical properties of F-center (two electrons trapped by an oxygen vacancy) defect in hematite have been studied using a quantum-chemical model. Calculated absorption energies, 0.9 eV and 3.6 eV, are discussed in terms of the available experimental data. An explanation for the origin of experimentally observed electron depletion in hematite is proposed.
GUIDED TRANSMISSION OF Cu- IONS THROUGH NANOCAPILLARIES IN Al2O3
Authors: CHEN Y. F. , YANG S. S. , CHEN X. M. , SUN G. Z. , WANG J.
Published: July 2010

We measured the transmission of 10 keV, 14 keV and 18 keV Cu - ions through Al 2 O 3 nanocapillaries of 50 nm diameter and 12 μm length at a series of different tilt angles. The surfaces of Al 2 O 3 capillaries were coated by Au . The angular distributions and the charged states of transported particles were investigated. Our results indicated the existence of a guiding effect when ions pass through the capillary. The transmitted particles were observed to lose the electrons easier at higher projectile energy and larger tilt angle. It was also found that the transmitted ions lose the electrons easier with lower ionization energy.
Reference Frames for Reach Planning in Human Parietofrontal Cortex
Authors: Beurze S. M. , Toni I. , Pisella L. , Medendorp W. P.
Published: July 2010

To plan a reaching movement, the brain must integrate information about the spatial goal of the reach with positional information about the selected hand. Recent monkey neurophysiological evidence suggests that a mixture of reference frames is involved in this process. Here, using 3T functional magnetic resonance imaging (fMRI), we tested the role of gaze-centered and body-centered reference frames in reach planning in the human brain. Fourteen human subjects planned and executed arm movements to memorized visual targets, while hand starting position and gaze direction were monitored and varied on a trial-by-trial basis. We further introduced a variable delay between target presentation and movement onset to dissociate cerebral preparatory activity from stimulus- and movement-related responses. By varying the position of the target and hand relative to the gaze line, we distinguished cerebral responses that increased for those movements requiring the integration of peripheral target and hand positions in a gaze-centered frame. Posterior parietal and dorsal premotor areas showed such gaze-centered integration effects. In regions closer to the primary motor cortex, body-centered hand position effects were found. These results suggest that, in humans, spatially contiguous neuronal populations operate in different frames of reference, supporting sensorimotor transformations according to gaze-centered or body-centered coordinates. The former appears suited for calculating a difference vector between target and hand location, whereas the latter may be related to the implementation of a joint-based motor command.