bluuebunny/crossref_metadata_2025 huggingface dataset:
OUTPUT‐INFLATION TRADEOFF IN CHINA
Authors: IMAI Hiroyuki
Published: March 2007

High growth and wide fluctuations in fixed investment are the main driving forces causing inflation in China during its economic reform period. Investment expansion generates strong demand pressures in the consumption goods market. Its inflationary impact is magnified further as it brings about higher wage costs during economic booms. In the paper, an implied short‐run tradeoff has been derived from the dynamic simulation of a small macroeconomic model. In a given year, each additional percentage point of aggregate output growth or investment growth will bring about a 2.6 or a 0.9 per cent increase, respectively, in the rate of inflation for that year. These estimates suggest that the surge in fixed investment accounts almost fully for the 1993–95 inflationary spell.
PRODUCTION RISK AND ADVANTAGES OF MIXED FARMING IN THE PAKISTAN PUNJAB
Authors: KUROSAKI Takashi
Published: March 2007

This paper proposes an empirical model of profit variability at the individual farm level and applies it to Pakistan's agriculture. Results show that the addition of idiosyncratic yield shocks and adjustment for input costs lead to a much larger variability of net profits than implied by the variability of average gross revenues–Pakistan's irrigated agriculture is associated with higher profit variability compared with semiarid India. It is also demonstrated that the correlation between green fodder profit and milk profit at the farm level is substantially negative. This negative correlation implies that it is advantageous, in terms of risk diversification, to combine fodder and milk production in one enterprise, which is commonly observed in the mixed farming systems in Pakistan's Punjab.
TECHNICAL, ECONOMIC, AND ALLOCATIVE EFFICIENCY IN PEASANT FARMING: EVIDENCE FROM THE DOMINICAN REPUBLIC
Authors: BRAVO‐URETA Boris E. , PINHEIRO António E.
Published: March 2007

This paper presents measures of technical (TE), economic (EE), and allocative (AE) efficiency for a sample of sixty peasant farmers in the Dajabon region of the Dominican Republic. Maximum likelihood techniques are used to estimate a Cobb‐Douglas production frontier, which is then used to derive its corresponding dual cost frontier. These frontiers are the basis for obtaining farm level efficiency estimates. The results reveal average levels of TE, AE, and EE equal to 70 per cent, 44 per cent, and 31 per cent, respectively. In a second step analysis, two‐limit tobit regression techniques are used to estimate three separate equations where TE, EE, and AE are expressed as functions of the following farm/farmer characteristics: contract farming, agrarian reform status, farm size, schooling, producer's age, and household size.
SOCIAL CLEAVAGES AND ELECTORAL SUPPORT IN TURKEY: TOWARD CONVERGENCE?
Authors: HAZAMA Yasushi
Published: March 2007

Studies on Western democracies have shown that deep‐seated social cleavages stabilize the electoral behavior and thus reduce electoral volatility. But how do social cleavages affect a party system that is undergoing democratic consolidation, such as in Turkey? In this study, investigations were carried out on long‐ and short‐term relationships between social cleavages (religiosity, ethnicity, and sectarism) electoral volatility in Turkey during the 1961–2002 period. Cross‐sectional multiple regressions were applied to electoral and demographic data at the provincial level. The results showed that in the longterm, social cleavages on the whole have increased volatility rather than reduced it. The cleavage‐volatility relationship, however, has changed over time. Repeated elections have mitigated the volatile effect of social cleavages on the voting behavior, as political parties have become more representative of the existent social cleavages.
IMPORT LIBERALIZATION AND PRODUCTIVITY GROWTH IN INDIAN MANUFACTURING INDUSTRIES IN THE 1990s
Authors: GOLDAR Bishwanath , KUMARI Anita
Published: March 2007

Total factor productivity growth in Indian manufacturing decelerated in the 1990s, a decade of major economic reforms in India. Econometric analysis presented in the paper indicates that the lowering of effective protection to industries favorably affected productivity growth. The results suggest that gestation lags in investment projects and slower agricultural growth in the 1990s had an adverse effect on productivity growth. The analysis reveals that underutilization of industrial capacity was an important cause of the productivity slowdown. With corrections for capacity utilization, the estimated productivity growth in the 1990s is found to be about the same as in the 1980s.
OWNERSHIP AND NONPERFORMING LOANS: EVIDENCE FROM TAIWAN'S BANKS
Authors: HU JIN‐LI , LI YANG , CHIU YUNG‐HO
Published: March 2007

We first derive a theoretical model to predict that the relation between nonperforming loan ratios and government shareholdings can be downward‐sloping, upward‐sloping, U‐shaped, and inversely U‐shaped. An increase in the government's shareholding facilitates political lobbying. On the other hand, private shareholding induces more nonperforming loans (NPLs) to be manipulated by corrupt private owners. We adopt a panel data set of forty Taiwanese commercial banks during 1996–99 for empirical analysis. The results show that the rate of NPLs decreased as the ratio of government shareholding in a bank rose (up to 63.51 percent), while the rate thereafter increased. Bank size was negatively related to the rate of NPLs. Rates of NPLs are shown to have steadily increased from 1996 to 1999. Banks established after deregulation, on average, had a lower rate of NPLs than those established before deregulation.
THE POTATO MARKETING SYSTEM AND ITS CHANGES IN BANGLADESH: FROM THE PERSPECTIVE OF A VILLAGE STUDY IN COMILLA DISTRICT
Authors: MOAZZEM Khondaker Golam , FUJITA Köichi
Published: March 2007

This paper analyzes the marketing system of potato in Bangladesh, especially the economic relations among farmers, traders, and cold storage owners and elucidates the structural changes in the rural economy through a village study. Investment in the potato market is capital‐intensive and risky, and is often considered to be vertically linked. The present study shows that farmers and cold storage owners do not invest in trading because of lack of time and “skill” to deal with urban traders. Besides, farmers face capital constraints and the amount of potatoes produced is too small to meet the demand of urban areas. Cold storage owners are confronted with increasing competition, which forces them to attempt to reach the storage capacity. Traders invest in the risky potato‐storage business. The return from it is declining but still high due to the “cheap” credit supply from the cold storage owners. There is no tied relation among the market agents any more.
SOCIAL SECURITY AND WELL‐BEING IN A LOW‐INCOME ECONOMY: AN APPRAISAL OF THE KERALA EXPERIENCE
Authors: Sato Hiroshi
Published: March 2007

The State of Kerala, which is considered to have attained a level of social well‐being comparable to that of advanced countries despite its relatively low income standard, is widely known as an example of “welfare by public intervention” in developing economies. This paper, focusing on the four areas of food provision, health services, elementary education, and pension schemes, and paying attention to the participation of the private sector as well as the activities of political parties and labor unions, points out that in Kerala, the private sector and organized activities have played a vital role, in addition to “public intervention,” in the betterment of public welfare.
Fibrinolytic characteristics and their significance in malignant, tuberculous and cirrhotic pleural and ascitic fluids
Authors: LU X.‐G. , MAO J.‐S. , TONG J.‐F. , ZHU L. , LIU J. , GONG X.‐B. , HUANG J.
Published: March 2007

The fibrinolytic characteristics and clinical pathological significance of pleural and ascitic fluid were studied in patients with malignant tumour, tuberculosis or liver cirrhosis. Urokinase plasminogen activator (uPA) and urokinase plaminogen activator receptor (uPAR) levels were measured by enzyme‐linked immunoadsorbent assay and tissue plasminogen activator (tPA), plasminogen activator inhibitor‐1 (PAI‐1), plasminogen (Plg), plasmin (Pl) and α2 plasmin inhibitor (α2PI) by colorimetric assay. uPA and uPAR levels were higher in malignant tumour and tuberculosis compared with liver cirrhosis, whereas tPA levels were significantly higher in liver cirrhosis and malignant tumour than in tuberculosis patients. Tuberculosis patients showed statistically higher PAI‐1, Plg and Pl concentrations than malignant tumour patients, which, in turn, were higher than those in liver cirrhosis patients. α2PI levels were markedly higher in malignant tumour and liver cirrhosis than in tuberculosis. In the malignant tumour group, only uPA level was significantly different between the samples that contained cancer cells and those that did not. We found significant differences between the fibrinolytic characteristics in pleural and ascitic fluid in patients with malignant tumour, tuberculosis and liver cirrhosis. The analysis of several fibrinolytic parameters could help to determine the quality of pleural and ascitic fluid, and also to further understand the pathological processes of these diseases.
Behaviour of reticulocyte counts and immature reticulocyte fraction during a competitive season in élite athletes of four different sports
Authors: BANFI G. , DEL FABBRO M.
Published: March 2007

The role of reticulocytes (Ret) in sports medicine became important when the count of immature erythrocytes has been introduced in protocols used and officially approved for antidoping purposes. The use of modern automated analysers, which allow the easy count and the description of characteristics of reticulocytes, increased the possible use of these parameters in sports medicine. We studied the behaviour of Ret and immature reticulocyte fraction (IRF) in top‐level athletes practising rugby, ski, soccer and cyclism, throughout a competitive season. We aimed at increasing the knowledge of physiological characteristics of these sportsmen and supplying valuable suggestions to trainers and sports physicians. We observed a stability of Ret counts, also during training and competitions, although some modifications, namely decrease during competitions periods in cyclists, and in rugby and soccer players, occurred. No significant correlation was found between Ret count and Hb in each sport discipline. IRF values tend to be high in athletes owing to continuous bone marrow stimulation linked to haemolysis, typical of sports activities. We confirm the validity of the use of Ret counts for antidoping purposes and also for evaluating health status and iron metabolism of sportsmen.
Haptoglobin: a review of the major allele frequencies worldwide and their association with diseases
Authors: CARTER KYMBERLEY , WORWOOD MARK
Published: March 2007

Haptoglobin (Hp) is a plasmaα2‐glycoprotein which binds free haemoglobin, thus preventing oxidative damage. The complex is rapidly removed from the circulation by a specific receptor (CD163) found on macrophages. Three major subtypes, Hp1‐1, Hp2‐1 and Hp2‐2 are the product of two closely related genes HP1and HP2. The frequency of the HP1and HP2genes varies worldwide depending on racial origin: the HP1frequency varying from about 0.07 in parts of India to over 0.7 in parts of West Africa and South America. Both HP1and HP2have been linked to susceptibility to various diseases. Such associations may be explained by functional differences between the subtypes in the binding of Hb and its rate of clearance from the plasma. However, there are also corresponding negative reports for disease associations. The conflicting evidence on disease association and the lack of association between disease and particular populations, despite the wide range of HP1and HP2gene frequencies across the world, may indicate that any associations are marginal.
Factors influencing the risk of common cuckoo Cuculus canorus parasitism on marsh warblers Acrocephalus palustris
Authors: Antonov Anton , G. Stokke Bård , Moksnes Arne , Røskaft Eivin
Published: March 2007

Using multiple logistic regression analysis, we investigated the influence of nest site characteristics, laying date and nest size in marsh warblers Acrocephalus palustris on the risk of parasitism by common cuckoos Cuculus canorus. Marsh warblers breed in more diverse and dense herbaceous vegetation than other cuckoo hosts investigated in comparable studies. The “perch proximity” hypothesis was supported as parasitized nests were situated closer to trees than non‐parasitized ones. Furthermore, demonstrated for the first time in a cuckoo host, tree height was an important predictor of parasitism, with higher trees increasing the parasitism odds ratio. The “nest exposure” hypothesis was also supported since parasitized nests had a shorter stand of vegetation in the close vicinity than non‐parasitized nests. However, visibility of the nest from the nearest potential cuckoo perch (cuckoo view) was not selected by the model, probably because most nests were well concealed. Laying date, height of nest above ground and the distance from the nest to the nearest edge of the vegetation were not important predictors of parasitism. Though smaller nests tended to be parasitized more frequently than larger ones, nest size only approached significance, making its importance unclear.
Spectrum analysis of seismic surface waves and its applications in seismic landmine detection
Authors: Alam Mubashir , McClellan James H. , Scott Waymond R.
Published: March 2007

In geophysics, spectrum analysis of surface waves (SASW) refers to a noninvasive method for soil characterization. However, the term spectrum analysis can be used in a wider sense to mean a method for determining and identifying various modes of seismic surface waves and their properties such as velocity, polarization, etc. Surface waves travel along the free boundary of a medium and can be easily detected with a transducer placed on the free surface of the boundary. A new method based on vector processing of space-time data obtained from an array of triaxial sensors is proposed to produce high-resolution, multimodal spectra from surface waves. Then individual modes can be identified in the spectrum and reconstructed in the space-time domain; also, reflected waves can be separated easily from forward waves in the spectrum domain. This new SASW method can be used for detecting and locating landmines by analyzing the reflected waves for resonance. Processing examples are presented for numerically generated data, experimental data collected in a laboratory setting, and field data.
Gaussian mixture model classification of odontocetes in the Southern California Bight and the Gulf of California
Authors: Roch Marie A. , Soldevilla Melissa S. , Burtenshaw Jessica C. , Henderson E. Elizabeth , Hildebrand John A.
Published: March 2007

A method for the automatic classification of free-ranging delphinid vocalizations is presented. The vocalizations of short-beaked and long-beaked common (Delphinus delphis and Delphinus capensis), Pacific white-sided (Lagenorhynchus obliquidens), and bottlenose (Tursiops truncatus) dolphins were recorded in a pelagic environment of the Southern California Bight and the Gulf of California over a period of 4 years. Cepstral feature vectors are extracted from call data which contain simultaneous overlapping whistles, burst-pulses, and clicks from a single species. These features are grouped into multisecond segments. A portion of the data is used to train Gaussian mixture models of varying orders for each species. The remaining call data are used to test the performance of the models. Species are predicted based upon probabilistic measures of model similarity with test segment groups having durations between 1 and 25s. For this data set, 256 mixture Gaussian mixture models and segments of at least 10s of call data resulted in the best classification results. The classifier predicts the species of groups with 67%–75% accuracy depending upon the partitioning of the training and test data.
Nonlinear acoustics in the pant hoots of common chimpanzees (Pan troglodytes): Vocalizing at the edge
Authors: Riede Tobias , Arcadi Adam Clark , Owren Michael J.
Published: March 2007

Common chimpanzee (Pan troglodytes) “pant hoots” are multi-call events that build from quiet, consistently harmonic introductory sounds to loud, screamlike “climax” calls with acoustic irregularities known as “nonlinear phenomena” (NLP). Two possible functions of NLP in climax calls are to increase direct auditory impact on listeners and to signal physical condition. These possibilities were addressed by comparing climax calls from 12 wild chimpanzee males with “screams” and pant hoot “introduction” calls from the same individuals. Climax calls that included NLP were found to have higher fundamental frequencies (F0s) than introduction or climax calls that were purely harmonic. NLP onsets within climax calls were also specifically associated with local F0 maxima, suggesting vocalizers are vibrating their vocal folds at the upper limits of stability. Furthermore, climax calls showed far fewer NLP than did screams recorded from the same individuals, while showing equivalent or higher F0 values. Overall, the results are consistent with the hypothesis that the relative prevalence of NLP is a signal of physical condition, with callers “vocalizing at the edge” of regular, stable production while producing few NLP. The results are discussed in light of the initial hypotheses.
A full vectorial contrast source inversion scheme for three-dimensional acoustic imaging of both compressibility and density profiles
Authors: van Dongen Koen W. A. , Wright William M. D.
Published: March 2007

Imaging the two acoustic medium parameters density and compressibility requires the use of both the acoustic pressure and velocity wave fields, described via integral equations. Imaging is based on solving for the unknown medium parameters using known measured scattered wave fields, and it is difficult to solve this ill-posed inverse problem directly using a conjugate gradient inversion scheme. Here, a contrast source inversion method is used in which the contrast sources, defined via the product of changes in compressibility and density with the pressure and velocity wave fields, respectively, are computed iteratively. After each update of the contrast sources, an update of the medium parameters is obtained. Total variation as multiplicative regularization is used to minimize blurring in the reconstructed contrasts. The method successfully reconstructed three-dimensional contrast profiles based on changes in both density and compressibility, using synthetic data both with and without 50% white noise. The results were compared with imaging based only on the pressure wave field, where speed of sound profiles were solely based on changes in compressibility. It was found that the results improved significantly by using the full vectorial method when changes in speed of sound depended on changes in both compressibility and density.
Word-internal versus word-peripheral consonantal duration patterns in three languages
Authors: Redford Melissa A.
Published: March 2007

Segmental duration patterns have long been used to support the proposal that syllables are basic speech planning units, but production experiments almost always confound syllable and word boundaries. The current study tried to remedy this problem by comparing word-internal and word-peripheral consonantal duration patterns. Stress and sequencing were used to vary the nominal location of word-internal boundaries in American English productions of disyllabic nonsense words with medial consonant sequences. The word-internal patterns were compared to those that occurred at the edges of words, where boundary location was held constant and only stress and sequence order were varied. The English patterns were then compared to patterns from Russian and Finnish. All three languages showed similar effects of stress and sequencing on consonantal duration, but an independent effect of syllable position was observed only in English and only at a word boundary. English also showed stronger effects of stress and sequencing across a word boundary than within a word. Finnish showed the opposite pattern, whereas Russian showed little difference between word-internal and word-peripheral patterns. Overall, the results suggest that the suprasegmental units of motor planning are language-specific and that the word may be more a relevant planning unit in English.
Sinusoidal modeling for nonstationary voiced speech based on a local vector transform
Authors: Ito Masashi , Yano Masafumi
Published: March 2007

A voiced speech signal can be expressed as a sum of sinusoidal components of which instantaneous frequency and amplitude continuously vary with time. Determining these parameters from the input, the time-varying characteristics are crucial error sources for the algorithms, which assume their stationarity within a local analysis segment. To overcome this problem, a new method is proposed, local vector transform (LVT), which can determine instantaneous frequency and amplitude for nonstationary sinusoids. The method does not assume the local stationarity. The effectiveness of LVT was examined in parameter determination for synthesized and naturally uttered speech signals. The instantaneous frequency for the first harmonic component was determined with an accuracy almost equal to that of the time-corrected instantaneous frequency method and higher accuracy than that of spectral peak-picking, autocorrelation, and cepstrum. The instantaneous amplitude was also determined accurately by LVT while considerable errors were left in the other algorithms. The signal reconstructed from the determined parameters by LVT agreed well with the corresponding component of voiced speech. These results suggest that the method is effective for analyzing time-varying voiced speech signals.
Statistically optimized near field acoustic holography using an array of pressure-velocity probes
Authors: Jacobsen Finn , Jaud Virginie
Published: March 2007

Statistically optimized near field acoustic holography (SONAH) differs from conventional near field acoustic holography (NAH) by avoiding spatial Fourier transforms; the processing is done directly in the spatial domain. The main advantage of SONAH compared with NAH is that the usual requirement of a measurement aperture that extends well beyond the source can be relaxed. Both NAH and SONAH are based on the assumption that all sources are on one side of the measurement plane whereas the other side is source free. An extension of the SONAH procedure based on measurement with a double layer array of pressure microphones has been suggested. The double layer technique makes it possible to distinguish between sources on the two sides of the array and thus suppress the influence of extraneous noise coming from the “wrong” side. It has also recently been demonstrated that there are significant advantages in NAH based on an array of acoustic particle velocity transducers (in a single layer) compared with NAH based on an array of pressure microphones. This investigation combines the two ideas and examines SONAH based on an array of pressure-velocity intensity probes through computer simulations as well as experimentally.
Comodulation detection differences in the hooded crow (Corvus corone cornix), with direct comparison to human subjects
Authors: Jensen Kenneth Kragh
Published: March 2007

Envelope modulations have been shown important in determining the effectiveness of masking noises. For example, the threshold for detecting a signal flanked by maskers is lower if the maskers and the signal are modulated with different envelopes, rather than the same envelope (comodulation). This threshold change is called the comodulation detection difference (CDD). CDDs were studied in two wild-caught hooded crows, using a 1.5kHz signal and two maskers at 0.9 and 2.1kHz, presented at an overall level of 55dB SPL (re 20μPa). For direct comparison with human psychophysics, three human subjects were tested in the same setup. CDDs averaged 15dB for the two crow subjects and 11dB for the human subjects. The species difference between average CDDs was insignificant. The significance of the CDD effect in a natural setting is discussed.
Reply to “Comment on ‘The directionality of acoustic T-phase signals from small magnitude submarine earthquakes’ [J. Acoust. Soc. Am. 119, 3669–3675 (2006)]”
Authors: Chapman N. Ross , Marrett R.
Published: March 2007

D. Bohnenstiehl has raised important issues about the interpretation of the T-phase directionality data presented in the paper by Chapman and Marrett [N. R. Chapman and R. Marrett, J. Acoust. Soc. Am. 119, 3669–3675 (2006)]. The central point in that Comment is that the maximum component in the T-phase signal is radiated directly from the earthquake source location. This Reply points out that the results in the original paper are not inconsistent with Bohnenstiehl’s model; moreover, the array directionality data contain significantly more information that can be useful in understanding the influence of bathymetric features in the radiation of T-phase sound by an earthquake.
A Bayesian method to estimate the depth and the range of phonating sperm whales using a single hydrophone
Authors: Laplanche Christophe
Published: March 2007

Some bioacousticians have used a single hydrophone to calculate the depth/range of phonating diving animals. The standard one-hydrophone localization method uses multipath transmissions (direct path, sea surface, and seafloor reflections) of the animal phonations as a substitute for a vertical hydrophone array. The standard method requires three multipath transmissions per phonation. Bioacousticians who study foraging sperm whales usually do not have the required amount of multipath transmissions. However, they usually detect accurately (using shallow hydrophones towed by research vessels) direct path transmissions and sea surface reflections of sperm whale phonations (clicks). Sperm whales emit a few thousand clicks per foraging dive, therefore researchers have this number of direct path transmissions and this number of sea surface reflections per dive. The author describes a Bayesian method to combine the information contained in those acoustic data plus visual observations. The author’s tests using synthetic data show that the accurate estimation of the depth/range of sperm whales is possible using a single hydrophone and without using any seafloor reflections. This method could be used to study the behavior of sperm whales using a single hydrophone in any location no matter what the depth, the relief, or the constitution of the seafloor might be.
Mucosal Tissue Invasion by
Candida albicans
Is Associated with E-Cadherin Degradation, Mediated by Transcription Factor Rim101p and Protease Sap5p
Authors: Villar C. C. , Kashleva H. , Nobile C. J. , Mitchell A. P. , Dongari-Bagtzoglou A.
Published: March 2007

The ability of
Candida albicans
to invade mucosal tissues is a major virulence determinant of this organism; however, the mechanism of invasion is not understood in detail. Proteolytic breakdown of E-cadherin, the major protein in epithelial cell junctions, has been proposed as a mechanism of invasion of certain bacteria in the oral mucosa. The objectives of this study were (i) to assess whether
C. albicans
degrades E-cadherin expressed by oral epithelial cells in vitro; (ii) to compare the abilities of strains with different invasive potentials to degrade this protein; and (iii) to investigate fungal virulence factors responsible for E-cadherin degradation. We found that while E-cadherin gene expression was not altered, E-cadherin was proteolytically degraded during the interaction of oral epithelial cells with
C. albicans
. Moreover,
C. albicans
-mediated degradation of E-cadherin was completely inhibited in the presence of protease inhibitors. Using a three-dimensional model of the human oral mucosa, we found that E-cadherin was degraded in localized areas of tissue invasion by
C. albicans
. An invasion-deficient
rim101
−
/
rim101
−
strain was deficient in degradation of E-cadherin, and this finding suggested that proteases may depend on Rim101p for expression. Indeed, reverse transcription-PCR data indicated that expression of the
SAP4
,
SAP5
, and
SAP6
genes is severely reduced in the
rim101
−
/
rim101
−
mutant. These
SAP
genes are functional Rim101p targets, because engineered expression of
SAP5
in the
rim101
−
/
rim101
−
strain restored E-cadherin degradation and invasion in the mucosal model. Our data support the hypothesis that there is a mechanism by which
C. albicans
invades mucosal tissues by promoting the proteolytic degradation of E-cadherin in epithelial adherens junctions.
Toxoplasma gondiiStrains Defective in Oral Transmission Are Also Defective in Developmental Stage Differentiation
Authors: Fux Blima , Nawas Julie , Khan Asis , Gill Darcy B. , Su Chunlei , Sibley L. David
Published: March 2007

Toxoplasma gondiiundergoes differentiation from rapidly growing tachyzoites to slowly growing bradyzoites during its life cycle in the intermediate host, and conversion can be induced in vitro by stress. Representative strains of the three clonal lineages showed equal capacity to differentiate into bradyzoites in vitro, as evidenced by induction of bradyzoite antigen 1, staining withDolichos bifloruslectin (DBL), pepsin resistance, and oral infectivity in mice. We also examined several recently described exotic strains ofT. gondii, which are genetically diverse and have a different ancestry from the clonal lineages. The exotic strain COUG was essentially like the clonal lineages and showed a high capacity to induce bradyzoites in vitro and in vivo, consistent with its ability to be efficiently transmitted by the oral route. In contrast, exotic strains MAS and FOU, which are defective in oral transmission, showed a decreased potential to develop into bradyzoites in vitro. This defect was evident from reduced staining with DBL and the cyst antigen CST1, failure to down-regulate tachyzoite antigens, such as tachyzoite surface antigens 1 and 2A, and decreased resistance to pepsin treatment. Despite normal in vitro differentiation, the exotic strains CAST and GPHT also showed decreased oral transmission, due to formation of smaller cysts and a lower tissue burden during chronic infection, traits also shared by MAS and FOU. Collectively, these findings reveal that the limited oral transmission in some strains ofT. gondiiis due to inefficient differentiation to the bradyzoite form, leading to defects in the formation of tissue cysts.
Role ofBacillus anthracis Spore Structures in Macrophage Cytokine Responses
Authors: Basu Subhendu , Kang Tae Jin , Chen Wilbur H. , Fenton Matthew J. , Baillie Les , Hibbs Steve , Cross Alan S.
Published: March 2007

The innate immune response of macrophages (Mφ) to spores, the environmentally acquired form ofBacillus anthracis, is poorly characterized. We therefore examined the early Mφ cytokine response toB. anthracisspores, before germination. Mφ were exposed to bacilli and spores of Sterne strain 34F2 and its congenic nongerminating mutant (ΔgerH), and cytokine expression was measured by real-time PCR and an enzyme-linked immunosorbent assay. The exosporium spore layer was retained (exo+) or removed by sonication (exo−). Spores consistently induced a strong cytokine response, with the exo−spores eliciting a two- to threefold-higher response than exo+spores. The threshold for interleukin-1β (IL-1β) production by wild-type Mφ was significantly lower than that required for tumor necrosis factor alpha expression. Cytokine production was largely dependent on MyD88, suggesting Toll-like receptor involvement; however, the expression of beta interferon in MyD88−/−Mφ suggests involvement of a MyD88-independent pathway. We conclude that (i) theB. anthracisspore is not immunologically inert, (ii) the exosporium masks epitopes recognized by the Mφ, (iii) the Mφ cytokine response toB. anthracisinvolves multiple pattern recognition receptors and signaling pathways, and (iv) compared to other cytokines, IL-1β is expressed at a lower spore concentration.
Second metatarsal stress fracture in sport: comparative risk factors between proximal and non-proximal locations
Authors: Chuckpaiwong Bavornrit , Cook Chad , Pietrobon Ricado , Nunley James A
Published: March 2007

Background:Stress fractures of the second metatarsal are common injuries in athletes and military recruits. There are two distinct areas in the second metatarsal where stress fractures develop: one proximal (at the base) and the other non-proximal (distal). Diagnosis can be difficult, and there is a difference in prognosis and treatment of the two types of stress fracture. Therefore differentiation of fracture location is warranted. Differences in risk factors and clinical outcomes between proximal and non-proximal stress fractures have not been studied.

Objective:To determine whether different risk factors and/or clinical outcomes associated with proximal and non-proximal stress fractures of the second metatarsal exist.

Methods:Patients diagnosed with proximal stress fractures of the second metatarsal were included in the study. Retrospectively, an age-matched control group with a non-proximal stress fracture was selected for comparison. Statistical analysis involved bivariate comparisons of demographic variables and clinical measurement between the two groups.

Results:Patients with proximal stress fractures were more likely to be chronically affected, usually exhibited an Achilles contracture, showed differences in length of first compared with second metatarsal, were more likely to experience multiple stress fractures, and exhibited low bone mass. In addition, a high degree of training slightly increased the risk of a non-proximal fracture, whereas low training volume was associated with a proximal stress fracture.

Conclusion:The signs, symptoms and clinical findings associated with proximal metatarsal stress fractures are different from those of non-proximal stress fractures.
PRIMITIVE IDEALS AND AUTOMORPHISM GROUP OF $U_{q}^{+}(B_{2})$
Authors: LAUNOIS STÉPHANE
Published: March 2007

Let 𝔤 be a complex simple Lie algebra of type B2 and q be a nonzero complex number which is not a root of unity. In the classical case, a theorem of Dixmier asserts that the simple factor algebras of Gelfand–Kirillov dimension 2 of the positive part U+(𝔤) of the enveloping algebra of 𝔤 are isomorphic to the first Weyl algebra. In order to obtain some new quantized analogues of the first Weyl algebra, we explicitly describe the prime and primitive spectra of the positive part [Formula: see text] of the quantized enveloping algebra of 𝔤 and then we study the simple factor algebras of Gelfand–Kirillov dimension 2 of [Formula: see text]. In particular, we show that the centers of such simple factor algebras are reduced to the ground field ℂ and we compute their group of invertible elements. These computations allow us to prove that the automorphism group of [Formula: see text] is isomorphic to the torus (ℂ*)2, as conjectured by Andruskiewitsch and Dumas.
LEFT QUOTIENT RINGS OF ALTERNATIVE RINGS
Authors: LOZANO MIGUEL GÓMEZ , MOLINA MERCEDES SILES
Published: March 2007

In this paper we develop a Fountain–Gould-like Goldie theory for alternative rings. We characterize alternative rings which are Fountain–Gould left orders in semiprime alternative rings coinciding with their socle, and those which are Fountain–Gould left orders in semiprime artinian alternative rings.
INTRODUCTION TO MODIFIED GRAVITY AND GRAVITATIONAL ALTERNATIVE FOR DARK ENERGY
Authors: NOJIRI SHIN'ICHI , ODINTSOV SERGEI D.
Published: March 2007

We review various modified gravities considered as gravitational alternative for dark energy. Specifically, we consider the versions of f(R), f(G) or f(R, G) gravity, model with non-linear gravitational coupling or string-inspired model with Gauss-Bonnet-dilaton coupling in the late universe where they lead to cosmic speed-up. It is shown that some of such theories may pass the Solar System tests. On the same time, it is demonstrated that they have quite rich cosmological structure: they may naturally describe the effective (cosmological constant, quintessence or phantom) late-time era with a possible transition from decceleration to acceleration thanks to gravitational terms which increase with scalar curvature decrease. The possibility to explain the coincidence problem as the manifestation of the universe expansion in such models is mentioned. The late (phantom or quintessence) universe filled with dark fluid with inhomogeneous equation of state (where inhomogeneous terms are originated from the modified gravity) is also described.
Adult-onset calorie restriction delays the accumulation of mitochondrial enzyme abnormalities in aging rat kidney tubular epithelial cells
Authors: McKiernan Susan H. , Tuen Victoria C. , Baldwin Katherine , Wanagat Jonathan , Djamali Arjang , Aiken Judd M.
Published: March 2007

Adult-onset calorie restriction (A-CR) is an experimental model of life extension and healthy aging less explored, compared with calorie restriction begun at early ages, but one more realistic for human application. We examined the effect of A-CR on the aging rat kidney with respect to common structural age-dependent changes and the accumulation of mitochondrial enzyme abnormalities in tubular epithelial cells. A 40% calorie restriction was initiated in middle-aged rats, before the onset of significant age-related changes in the Fischer × Brown Norway rat kidney. This dietary intervention effectively reduced glomerulosclerosis and tubular atrophy within 6 mo and changed the rate of interstitial fibrosis formation within 1 yr and vascular wall thickening and the expression cytochrome c oxidase (COX)-deficient tubular epithelial cells in 18 mo compared with age-matched ad libitum-fed rats. Our histological approach (histochemical staining for mitochondrial enzyme activity and laser capture microdissection) coupled with mitochondrial DNA (mtDNA) PCR analyses demonstrated that COX-deficient renal tubular epithelial cells accumulated mtDNA deletion mutations and that these cells contained unique, clonally expanded mtDNA deletion mutations. Renal tubular epithelial cells with mitochondrial abnormalities presented cellular characteristics indicative of physiological dysfunction.
Sex-differential expression of ornithine aminotransferase in the mouse kidney
Authors: Levillain Olivier , Ventura Gabrielle , Déchaud Henri , Hobeika Maya , Meseguer Anna , Moinard Christophe , Cynober Luc
Published: March 2007

The mouse kidney expresses the gene of ornithine aminotransferase ( Oat). Previous works suggest that Oat is differentially expressed in female and male mouse kidney (Alonso E, Rubio V. Biochem J 259: 131–138, 1989; Levillain O, Diaz JJ, Blanchard O, Dechaud H. Endocrinology 146: 950–959, 2005; Manteuffel-Cymborowska M, Chmurzynska W, Peska M, Grzelakowska-Sztabert B. Int J Biochem Cell Biol 27: 287–295, 1995; Natesan S, Reddy SR. Comp Biochem Physiol B Biochem Mol Biol 130: 585–595, 2001; Yu H, Yoo PK, Aguirre CC, Tsoa RW, Kern RM, Grody WW, Cederbaum SD, Iyer RK. J Histochem Cytochem 51: 1151–1160, 2003). This study was designed to provide a detailed description of the sexual dimorphism of Oat expression in the mouse kidney and to test the influence of sex hormones on its regulation. Experiments were performed on male and female Swiss OF1 mice during their postnatal development, at adulthood, and in orchidectomized and ovariectomized mice. Kidneys, dissected renal zones, and mitochondria were used to analyze OAT mRNA and protein levels and measure OAT activity. The results revealed that before puberty, Oat expression was similar between female and male kidneys whereas from puberty until adulthood Oat expression increased in the female kidney, becoming ≈2.5-fold higher than in the male kidney. This sex-differential expression of Oat was associated with a sex-specific distribution of Oat along the corticopapillary axis and within the nephron. OAT was three- to fourfold more expressed in the female than the male cortex. In males, Oat was highly expressed in the medulla, mainly in the thick ascending limbs. Renal Oat distribution in orchidectomized mice resembled that in the females. Ovariectomy did not influence Oat expression. Sex differences are explained by the physiological increase in plasma testosterone in males. Expression of medium-chain acyl-CoA synthetase protein confirmed this finding. We report sexual dimorphism of Oat expression in the mouse kidney and show that Oat is naturally downregulated in the presence of testosterone.
Packet-Loss Modeling for Perceptually Optimized 3D Transmission
Authors: Cheng Irene , Ying Lihang , Basu Anup
Published: March 2007

Transmissions over unreliable networks, for example, wireless, can lead to packet loss. An area that has received limited research attention is how to tailor multimedia information taking into account the way packets are lost. We provide a brief overview of our research on designing a 3D perceptual quality metric integrating two important factors, resolution of texture and resolution of mesh, which control transmission bandwidth, followed by a suggestion on alternative strategies for packet 3D transmission of both texture and mesh. These strategies are then compared with respect to preserving 3D perceptual quality under packet loss in ad hoc wireless networks. Experiments are conducted to study how buffer size, sending rate, sending intervals, and packet size can affect loss in unreliable channels. A model for estimating the optimal packet size is then proposed. We derive the optimal number of packets based on this model, and relate the theoretical derivations to actual network data.
Di‐n‐butyltin(IV) Complexes Derived from Heterocyclic β‐diketones and N‐Phthaloyl Amino Acids: Preparation,Biological Evaluation, Structural Elucidation Basedupon Spectral [IR, NMR (1H, 13C, 19F and 119Sn)] Studies
Authors: Joshi Anurag , Verma Shashi , Gaurb R. B. , Sharma R. R.
Published: March 2007

Stable, six coordinated Bu2SnLA type complexes have been prepared [where LH =
; R = ‐4‐F‐C6H4‐(L1H), R = ‐4‐Cl‐C6H4‐(L2H), R= ‐4‐Br‐C6H4‐(L3H), R=
‐CF3(L4H) and ; R′= ‐H(A1H), ‐CH3(A2H), ‐CH(CH3)2(A3H)] by the
interaction of 1:1:1 molar ratios of di‐n‐butyltin(IV) dichloride with corresponding organic moieties in
refluxing benzene using two moles of Et3N as a base. In these complexes LH and AH behave as bidentate
and coordination is taking place through oxygen, this is inferred from IR and 13C NMR studies. These
complexes possess tin atoms in skew trapezoidal bipyramidal geometry with the C‐Sn‐C angles ranging from
149.88° to 156.84°. Some of these complexes with their corresponding organic moieties (LH, AH) were
tested for their antimicrobial activities.
Sulforaphane induces cell type–specific apoptosis in human breast cancer cell lines
Authors: Pledgie-Tracy Allison , Sobolewski Michele D. , Davidson Nancy E.
Published: March 2007

Sulforaphane, an isothiocyanate found in cruciferous vegetables, has been shown to induce phase 2 detoxication enzymes and inhibit the growth of chemically induced mammary tumors in rats, although the exact mechanisms of action of sulforaphane are not understood. In this study, we evaluated the effects of sulforaphane on cell growth and death in several human breast cancer cell lines and examined the hypothesis that sulforaphane acts as a histone deacetylase (HDAC) inhibitor in these cell lines. Sulforaphane treatment inhibited cell growth, induced a G2-M cell cycle block, increased expression of cyclin B1, and induced oligonucleosomal DNA fragmentation in the four human breast cancer cell lines examined, MDA-MB-231, MDA-MB-468, MCF-7, and T47D cells. Activation of apoptosis by sulforaphane in MDA-MB-231 cells seemed to be initiated through induction of Fas ligand, which resulted in activation of caspase-8, caspase-3, and poly(ADP-ribose) polymerase, whereas apoptosis in the other breast cancer cell lines was initiated by decreased Bcl-2 expression, release of cytochrome c into the cytosol, activation of caspase-9 and caspase-3, but not caspase-8, and poly(ADP-ribose) polymerase cleavage. Sulforaphane inhibited HDAC activity and decreased the expression of estrogen receptor-α, epidermal growth factor receptor, and human epidermal growth factor receptor-2 in each cell line, although no change in the acetylation of H3 or H4 was seen. These data suggest that sulforaphane inhibits cell growth, activates apoptosis, inhibits HDAC activity, and decreases the expression of key proteins involved in breast cancer proliferation in human breast cancer cells. These results support testing sulforaphane in vivo and warrant future studies examining the clinical potential of sulforaphane in human breast cancer. [Mol Cancer Ther 2007;6(3):1013–21]
Selenium sensitizes MCF-7 breast cancer cells to doxorubicin-induced apoptosis through modulation of phospho-Akt and its downstream substrates
Authors: Li Song , Zhou Yunfei , Wang Ruiwen , Zhang Haitao , Dong Yan , Ip Clement
Published: March 2007

Doxorubicin is an effective drug against breast cancer. However, the favorable therapeutic response to doxorubicin is often associated with severe toxicity. The present research was aimed at developing a strategy of increasing doxorubicin sensitivity so that lower doses may be used without compromising efficacy. The MCF-7 human breast cancer cell line currently in use in our laboratory did not respond to doxorubicin cell killing during a 24-h treatment period. By combining doxorubicin with selenium, we were successful in producing a brisk enhancement of apoptosis. We examined the effects of these two agents on Akt activation and found that selenium was capable of depressing doxorubicin-induced Akt phosphorylation. Several lines of evidence converged to support the notion that this effect is important in mediating the synergy between selenium and doxorubicin. Selenium was no longer able to sensitize cells to doxorubicin under a condition in which Akt was constitutively activated. Increased Akt phosphorylation following treatment with doxorubicin was accompanied by increased phosphorylation of glycogen synthase kinase 3β (GSK3β) and FOXO3A, which are substrates of Akt (both GSK3β and FOXO3A lose their proapoptotic activities when they are phosphorylated). Selenium reduced the abundance of phospho-GSK3β induced by doxorubicin, whereas chemical inhibition of GSK3β activity muted the apoptotic response to the selenium/doxorubicin combination. Additional experiments showed that selenium increased the transactivation activity of FOXO3A, as evidenced by a reporter gene assay, as well as by the elevated expression of Bim (a target gene of FOXO3A). The functional significance of Bim was confirmed by the observation that RNA interference of Bim markedly reduced the potency of selenium/doxorubicin to induce apoptosis. [Mol Cancer Ther 2007;6(3):OF1–8