bluuebunny/crossref_metadata_2025_split huggingface dataset:
Agricultural farming alters predator–prey interactions in nearby natural habitats
Authors: Shapira I. , Sultan H. , Shanas U. 
Published: November 2007

AbstractAgricultural farming is a major consumer of global arable lands and has a direct effect on species decline through habitat destruction. However, agricultural endeavours can also evoke indirect threats that will result in behavioural modifications of indigenous species. In a desert ecosystem, where a political border led to a farming dichotomy between intensive cultivates in Israel and intact lands in Jordan, we compared the foraging behaviours and abundances of the red fox and two species of gerbils, close to and distant from farms, and during two moon phases. We estimated fox and gerbil foraging levels by track counts, and measured gerbil time allocation, vigilance and apprehension by the giving‐up density method. While foxes were significantly more abundant and active at locations close to farms, gerbils were significantly more abundant and active at locations distant from farms. Moreover, the typical reduction in food consumption during full‐moon nights was exhibited only at locations close to farms. These results could suggest that indicators of predation risk, such as illumination intensity or distance to cover, are not universal, and their effectiveness may depend indirectly on anthropogenic activities, such as agricultural farming. The results could also suggest that although intensive agricultural endeavours benefit foxes, they might increase the predatory pressure on gerbils in addition to the already known effects of habitat loss. Therefore, agriculture acts as a double‐edged sword by reducing natural habitats, while at the same time changing the predator–prey natural balance.
Metabolically engineered bacteria for producing hydrogen via fermentation
Authors: Vardar‐Schara Gönül , Maeda Toshinari , Wood Thomas K. 
Published: November 2007

SummaryHydrogen, the most abundant and lightest element in the universe, has much potential as a future energy source. Hydrogenases catalyse one of the simplest chemical reactions, 2H+ + 2e‐ ↔ H2, yet their structure is very complex. Biologically, hydrogen can be produced via photosynthetic or fermentative routes. This review provides an overview of microbial production of hydrogen by fermentation (currently the more favourable route) and focuses on biochemical pathways, theoretical hydrogen yields and hydrogenase structure. In addition, several examples of metabolic engineering to enhance fermentative hydrogen production are presented along with some examples of expression of heterologous hydrogenases for enhanced hydrogen production.
In Vitro Antifungal Susceptibilities of Five Species ofSporothrix
Authors: Marimon Rita , Serena Carolina , Gené Josepa , Cano Josep , Guarro Josep 
Published: November 2007

ABSTRACTNinety-two isolates belonging to five species of theSporothrix schenckiicomplex were tested in vitro against 12 antifungal agents, using a reference microdilution method. There were significant differences among the species;Sporothrix brasiliensiswas the species that showed the best response to antifungals, andS. mexicanahad the worst response. In general, terbinafine was the most active drug, followed by ketoconazole and posaconazole.
Differential Roles of Poly-
N
-Acetylglucosamine Surface Polysaccharide and Extracellular DNA in
Staphylococcus aureus
and
Staphylococcus epidermidis
Biofilms
Authors: Izano Era A. , Amarante Matthew A. , Kher William B. , Kaplan Jeffrey B. 
Published: November 2007

ABSTRACT

Staphylococcus aureus
and
Staphylococcus epidermidis
are major human pathogens of increasing importance due to the dissemination of antibiotic-resistant strains. Evidence suggests that the ability to form matrix-encased biofilms contributes to the pathogenesis of
S. aureus
and
S. epidermidis
. In this study, we investigated the functions of two staphylococcal biofilm matrix polymers: poly-
N
-acetylglucosamine surface polysaccharide (PNAG) and extracellular DNA (ecDNA). We measured the ability of a PNAG-degrading enzyme (dispersin B) and DNase I to inhibit biofilm formation, detach preformed biofilms, and sensitize biofilms to killing by the cationic detergent cetylpyridinium chloride (CPC) in a 96-well microtiter plate assay. When added to growth medium, both dispersin B and DNase I inhibited biofilm formation by both
S. aureus
and
S. epidermidis
. Dispersin B detached preformed
S. epidermidis
biofilms but not
S. aureus
biofilms, whereas DNase I detached
S. aureus
biofilms but not
S. epidermidis
biofilms. Similarly, dispersin B sensitized
S. epidermidis
biofilms to CPC killing, whereas DNase I sensitized
S. aureus
biofilms to CPC killing. We concluded that PNAG and ecDNA play fundamentally different structural roles in
S. aureus
and
S. epidermidis
biofilms.
The Weak-Acid Preservative Sorbic Acid Is Decarboxylated and Detoxified by a Phenylacrylic Acid Decarboxylase, PadA1, in the Spoilage Mold
Aspergillus niger
Authors: Plumridge Andrew , Stratford Malcolm , Lowe Kenneth C. , Archer David B. 
Published: November 2007

ABSTRACT

Resistance to sorbic and cinnamic acids is mediated by a phenylacrylic acid decarboxylase (PadA1) in
Aspergillus niger. A. niger ΔpadA1
mutants are unable to decarboxylate sorbic and cinnamic acids, and the MIC of sorbic acid required to inhibit spore germination was reduced by ∼50% in Δ
padA1
mutants.
Efficient Antibody Production upon Suppression of O Mannosylation in the Yeast
Ogataea minuta
Authors: Kuroda Kousuke , Kobayashi Kazuo , Kitagawa Yoshinori , Nakagawa Taishiro , Tsumura Haruhiko , Komeda Toshihiro , Shinmi Daisuke , Mori Eiji , Motoki Kazuhiro , Fuju Kazumi , Sakai Teruyuki , Nonaka Koichi , Suzuki Takeshi , Ichikawa Kimihisa , Chiba Yasunori , Jigami Yoshifumi 
Published: November 2007

ABSTRACT

When antibodies were expressed in the methylotrophic yeast
Ogataea minuta
, we found that abnormal O mannosylation occurred in the secreted antibody. Yeast-specific O mannosylation is initiated by the addition of mannose at serine (Ser) or threonine (Thr) residues in the endoplasmic reticulum via protein O mannosyltransferase (Pmt) activity. To suppress the addition of O-linked sugar chains on antibodies, we examined the possibility of inhibiting Pmt activity by the addition of a Pmt inhibitor during cultivation. The Pmt inhibitor was found to partially suppress the O mannosylation on the antibodies. Surprisingly, the suppression of O mannosylation was associated with an increased amount of assembled antibody (H2L2) and enhanced the antigen-binding activity of the secreted antibody. In this study, we demonstrated the expression of human antibody in
O. minuta
and elucidated the relationship between O mannosylation and antibody production in yeast.
MyD88 Signaling Contributes to Early Pulmonary Responses toAspergillus fumigatus
Authors: Bretz Camille , Gersuk Geoff , Knoblaugh Sue , Chaudhary Neelkamal , Randolph-Habecker Julie , Hackman Robert C. , Staab Janet , Marr Kieren A. 
Published: November 2007

ABSTRACTToll-like receptors and the β-glucan receptor, dectin-1, mediate macrophage inflammatory responses toAspergillus fumigatusthrough MyD88-dependent and -independent signaling mechanisms; however, pulmonary inflammatory responses in MyD88-deficient mice challenged withA. fumigatusare poorly defined. The role of MyD88 signaling in early pulmonary inflammation and fungal clearance was evaluated in C57BL/6J wild-type (WT) and MyD88-deficient (MyD88−/−) mice. Early (<48 h) after infection, MyD88−/−mice had higher fungal burdens than those of WT mice, although fungal burdens rapidly declined (>72 h) in both. MyD88−/−mice had less consolidated inflammation, with fewer NK cells, in lung tissue early (24 h) after infection than did WT mice. At the latter time point, MyD88−/−mouse lungs were characterized by a large amount of necrotic cellular debris and fibrin, while WT lungs had organized inflammation. Although there were equivalent numbers of macrophages in WT and MyD88−/−mouse lung tissues, MyD88−/−cells demonstrated delayed uptake of green fluorescent protein-expressingA. fumigatus(GFP-Af293); histologically, MyD88−/−mouse lungs had more hyphal invasion of terminal airways and vessels, the appearance of bronchiolar epithelial cell necrosis, and necrotizing vasculitis. MyD88−/−lung homogenates contained comparatively decreased amounts of interleukin-1β (IL-1β), IL-6, KC, and gamma interferon and paradoxically increased amounts of tumor necrosis factor alpha and macrophage inflammatory protein 1α. These data indicate that the MyD88-dependent pathway mediates acute pulmonary fungal clearance, inflammation, and tissue injury very early after infection. Resolution of abnormalities within a 3-day window demonstrates the importance of redundant signaling pathways in mediating pulmonary inflammatory responses to fungi.
Modulation of Horizontally Acquired Genes by the Hha-YdgT Proteins in
Salmonella enterica
Serovar Typhimurium
Authors: Vivero Aitziber , Baños Rosa C. , Mariscotti Javier F. , Oliveros Juan Carlos , García-del Portillo Francisco , Juárez Antonio , Madrid Cristina 
Published: November 2007

ABSTRACT

We describe a transcriptomic study of the effect of
hha
and
ydgT
mutations in
Salmonella enterica
serovar Typhimurium. A large number of genes showing altered expression are located in AT-rich horizontally acquired DNA sequences. Many of these genes have also been reported to be targets for H-NS. As Hha and YdgT interact with H-NS, our findings strongly suggest that Hha and/or YdgT must form complexes with H-NS when they silence these DNA regions.
Environmental Factors Affecting Tropical Cyclone Power Dissipation
Authors: Emanuel Kerry 
Published: November 2007

Abstract
Revised estimates of kinetic energy production by tropical cyclones in the Atlantic and western North Pacific are presented. These show considerable variability on interannual-to-multidecadal time scales. In the Atlantic, variability on time scales of a few years and more is strongly correlated with tropical Atlantic sea surface temperature, while in the western North Pacific, this correlation, while still present, is considerably weaker. Using a combination of basic theory and empirical statistical analysis, it is shown that much of the variability in both ocean basins can be explained by variations in potential intensity, low-level vorticity, and vertical wind shear. Potential intensity variations are in turn factored into components related to variations in net surface radiation, thermodynamic efficiency, and average surface wind speed.
In the Atlantic, potential intensity, low-level vorticity, and vertical wind shear strongly covary and are also highly correlated with sea surface temperature, at least during the period in which reanalysis products are considered reliable. In the Pacific, the three factors are not strongly correlated. The relative contributions of the three factors are quantified, and implications for future trends and variability of tropical cyclone activity are discussed.
Paul Sérant and the extreme right's rhetoric of antithesis
Authors: Frey Hugo 
Published: November 2007

The starting point for this article is Paul Sérant's novel, Le Meurtre rituel (1950). It is a significant work for political and cultural historians because it reveals a dominant rhetorical perspective common to many other literary and non-literary texts written by extreme right-wing intellectuals in France. In particular the article highlights how Sérant's novel exemplifies the group's fascination with the idea of polarity: that is to say dramatic comparisons between seemingly contradictory concepts. Certainly, this aspect of Sérant's novel foreshadows the thesis presented in his better-known historiography, Le Romantisme fasciste (1959). It also perpetuates themes which were common in the work of Henry de Montherlant and Drieu la Rochelle, among others. The dominant `polarity' theme running through Le Meurtre rituel supported Sérant's encouragement for a U-turn from the corrupt political space of Fourth Republic France to a new and rich spiritual zone. The article explores how this lesson was commonly taken up in the 1950s by other right-wingers who, like Sérant, also searched for the `sacred' in a variety of esoteric schools of thought. It will also highlight the historical roots of the esoteric drift and examine its after-e fects, notably its influence on thinkers associated with the 1970s nouvelle droite . However, Sérant did not manage to execute all of the inversions encouraged in his rhetoric. The article concludes with consideration of Sérant's failed exchange: his retention of the anti-Semitic trope of ritual murder in the novel.
The use of system dynamics in manufacturing systems engineering
Authors: Edghill Jane , Towill Denis 
Published: November 2007

This paper considers the characteristic dynamic behaviour associated with basic manufacturing system designs. In studying such systems the focus will be on three fundamental flows: orders; materials; and information. Of specific interest is the influence of these flows on scheduling decision rules based on stock levels and/or product order rates, as well as how information is passed through the system. Thus it is the optimum combination of feedforward and/or feedback flow paths in a manufacturing-system design which is being sought. This paper will propose a 'middle ground' between two categories of technique used when considering dynamic behaviour - i e, building models using continuous computer simulation packages and alternatively using models capable of mathematical solution. It is proposed that mathematical models, of limited complexity, can provide the necessary insight to guide the design and appraisal of live system models built with a continuous computer package. The paper concludes by developing the idea that a generic application in the study of scheduling strategies for live manufacturing systems.
Minimisation of computation for digital controllers
Authors: Goodall R.M. 
Published: November 2007

A novel Structure is described and analysed which has a number of advantages for the practical implementation of recursive digital filters in control applications. It is based upon the use of an established alternative to the usual z-1 delay operator, but this has been developed into a standard form called a δ filter which is both robust and versatile. The advantages are shown to be in the simplicity of implementation, including the determination of word-lengths for the coefficients and variables. First- and second-order filter structures are given in detail, and simulations presented to demonstrate the operation of a few typical filters. Significant reductions in computation requirements are possible using the δ filter.
Active position control of stepping motors with flexible transmission shaft
Authors: Firoozian R. , Bajir J.G. 
Published: November 2007

In this paper the authors present an active control algorithm for position control of stepping servomotors with flexible transmission shaft. A non-linear mathematical model is derived to describe the dynamic behaviour of the system. To implement the full state-variable active-control technique, the non-linear model is first linearised. It is shown that the full state variables could be used in a closed-loop controller to introduce damping in the eigenvalues of the system. For realistic application of active control, a state estimator (observer) is used to construct the full state variables from a single measured signal. The estimated state variables are fed in the controller to generate the control signal. It is shown that this method facilitates the introduction of damping in all eigenvalues of the system and so eliminates the undesirable oscillation due to the flexibility of the transmission shaft. Furthermore the effectiveness of linear control algorithm on the non-linear system is studied.
A new measurement system for high-resolution tactile imaging
Authors: Gelaky R. , Keating D. 
Published: November 2007

Over the last 12 years, consistent effort has been directed toward the development of a usable sense of touch for machines. This research has been somewhat overshadowed by the ongoing development in artificial vision, but has remained important for specialised object identification applications. Over the aforementioned period, a great number of different transduction and measurement principles have been adopted, each claiming to offer certain desirable characteristics. The last five years have shown a reduction in the variation of methods being pursued. One of the main surviving transduction methods is based upon the variable-separation capacitive transducer. The method of capacitance measurement, adopted by two major American research teams developing such sensors, has been a simple charge amplifier. Their measurement methodology has limited the spatial resolution, or inter-tactel separation, and slowed the acceptance of an otherwise near ideal taction device. This paper describes the development, a design model and subsequent construction, of a variable-separation capacitive tactile system which employs an improved measurement system. The system permits the sensor spatial separation to be reduced to the limits of the physical construction method and no longer be confined by the measurement technique. This will, it is hoped, lead to the construction of larger, more densely packed, arrays capable of low-cost, efficient object recognition. The sensor performance, possible applications and intended direction for further research are also discussed.
Submarine periscope-depth depth-keeping using an H-infinity controller together with sea-noise-reduction notch filters
Authors: Marshfield W.B. 
Published: November 2007

The paper shows the usefulness of H-infinity techniques in designing a depth-control autopilot for a submarine at periscope depth. It also shows that a significant reduction in nugatory hydroplane activity can be effected if tracking notch filters are included in the autopilot inputs to discriminate against wave frequencies. The results of simulations of a submarine at periscope depth in sea-state 5 in bow and stern seas are given. The simulation uses a full six-degrees-of-freedom nonlinear mathematical model of the submarine. Depth control is maintained using an H-infinity controller designed using a linear mathematical model of the submarine. The inputs to the controller are depth and pitch and the outputs are bow and stern hydroplane angles. Both input signals contain noise at wave frequencies which cause nugatory motions of the hydroplanes. Previous work, (Daniel and Richards, 1983), with LQG (Linear, Quadratic, Gaussian) controller designs showed that notch filters, designed to track the predominant wave frequency, could be used to reduce the hydroplane activity at periscope depth. This technique has now been applied successfully to an H-infinity controller.
A differential system simulator for process dynamics and control design
Authors: Zhu Zhong-Xiang , Jutan A. 
Published: November 2007

A Simulation System- MDSS- is developed for the Dynamic Simulation of Systems described by ordinary and partial differential equations. MDSS has unique features in system management, structure design, data processing and input-output interface, in addition to its powerful equation-solution functions with a built-in integration 'engine', which allows for interactive analysis of complec dynamic systems and design of control loops.
A generalised algorithm for polarity correlation estimation using binary patterns
Authors: Harba M.I.A. 
Published: November 2007

A recently developed binary-pattern correlator uses the binary patterns of a group of successive samples of the polarity-sampled signal for correlation estimation. At high sampling rates (compared to the bandwidth of the signal), only a limited number of polarity changes may take place within a finite signal duration. Thus, a finite interval of a polarity-sampled signal may only have a limited set of binary patterns. The correlator estimates the frequency of occurrence of these patterns on-line and stores them in tables. The actual correlation coefficients are then deduced from these tables. Because the number of patterns is limited, efficient operation results. A general binary-pattern correlation algorithm is presented, with examples implemented on a Z-80 microprocessor. These examples represent different implementations of the algorithm. They differ in the number of signal samples effectively input each time, and in the size of the frequency of pattern-occurrence tables. As a result they have different sampling rates, and different off-line processing intervals. However, there is a trade-off between the achieved sampling rate and the amount of off-line processing.
Non-linear and unsteady flow analysis of flow in a viscous flowmeter
Authors: Stone C.R. , Wright S.D. 
Published: November 2007

An experimental and theoretical investigation has been undertaken on a viscous flowmeter, with both steady and unsteady flow. The steady flow analysis quantifies the nonlinear effects of entry and exit losses, development length effects and compressibility effects. The steady flow analysis and experiments show that the pressure drop has a quadratic response to flowrate, but that for practical applications a linear approximation will lead to an error of less than 1%. The unsteadyflow experiments show that it is necessary to integrate the instantaneous flow over a whole number of cycles, in order to obtain reliable values of the mean flow. An analysis of unsteady viscous flow has been used to show how the instantaneous pressure difference measured across the viscous flowmeter can be analysed to give the instantaneous volume flow rate.
Tactile and kinaesthetic feedback in virtual environments
Authors: Taylor Paul 
Published: November 2007

Virtual reality technology has great potential for design for assembly, disassembly and maintenance but such manipulation tasks by their very nature involve tactile and kinaesthetic interaction. Consequently, a new generation of tools needs to be developed to provide the appropriate tactilelkinaesthetic feedback to the user in order to complement the traditional visual technology. Three feedback devices will be described arising from research supported by the EPSRC and BRITE-EURAM. (1) A 2½-D programmable surface using shape-memory alloy wires. (2) A surface with programmable compliance using electro-rheological fluids. Haptic searching over the surface gives the illusion of the presence of an object. (3) The Reactabot™ , a robot-like device which provides force feedback to the user and is programmed to mimic the dynamic characteristics of the virtual object and its interaction both with the virtual environment and the operator.