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Human monkeypox is a severe and rare smallpox-like illness that occurs sporadically in remote villages in the tropical rain forest of West and Central Africa (2,2). The causative agent, monkeypox [...]

When the National Industrial Recovery Act (NIRA) of 1933 is discussed, whether at academic conferences or in the classroom, an audience member seems invariably to ask some version of the [...]

In the United States, New York orthohantavirus (NYV) is carried by the white-footed mouse (Peromyscus leucopus). During 1993-1995, human cases of NYV infection were reported in persons who visited or [...]

Abstract Beaudreau (1996) argued that the decline in investment expenditure in the early 1930s was the result of two factors, namely the electrification of U.S. manufacturing in the 1910s and [...]

James Essegbey, Brent Henderson and Fiona McLaughlin (editors), Language Documentation and Endangerment in Africa. Amsterdam: John Benjamins (hb 105 [euro]/US$ 158-978 9 02724 452 9). 2015, 317 pp. This is [...]

Weldemichael, Awet Tewelde. 2013. THIRD WORLD COLONIALISM AND STRATEGIES OF LIBERATION: ERITREA AND EAST TIMOR COMPARED. Cambridge: Cambridge University Press. 348 pp. $99.00 (cloth). Awet Tewelde Weldemichael, of the University [...]

For half a century, red spruce (Picea rubens Sarg.), a commercially and ecologically important boreal tree species, has experienced growth decline and high mortality in eastern North America. A tree growth systems model, ARIM (annual radial increment model), was developed to evaluate responsible factors for red spruce growth in the Great Smoky Mountains National Park. The dominant cause at higher elevations (1800-2000 m) was found to be air pollution involving high-frequency acidic rain and cloud immersion. The identified causes at lower elevations (1450-1700 m) were insufficient solar absorption due to photoinhibition, drought stress resulting from reduced precipitation and high evapotranspiration due to warmer temperatures, and minor effects of air pollution. The ARIM exemplifies a complex systems concept and methodology for evaluating multivariable factors in tree growth systems. ARIM provides a general model structure that incorporates complex direct and indirect interactions for tree system studies and quantitatively integrates knowledge and data from different disciplines by developing a new set of indices, the relative basis index values. The ARIM results implicate comprehensive habitat-dependent directions for long-term conservation policies and management of red spruce with environmental changes, climate change, and air pollution in the Great Smoky Mountains National Park. Depuis un demi-siecle, l'epinette rouge (Picea rubens Sarg.), une essence boreale importante du point de vue commercial et ecologique, connait une baisse de croissance et une forte mortalite dans l'est de l'Amerique du Nord. Un modele de croissance, MARA (modele d'accroissement radial annuel), a ete developpe pour evaluer les facteurs responsables de la croissance de l'epinette rouge dans le parc national des Great Smokey Mountains. A haute altitude (1 800 a 2 000 m), nous avons identifie la pollution de l'air, impliquant la frequence elevee de pluie acide et d'immersion nuageuse, comme cause dominante. Les causes identifiees a basse altitude (1 450 a 1 700 m) etaient l'absorption insuffisante de rayonnement solaire due a la photo-inhibition, le stress cause par la secheresse due a la diminution des precipitations et a une forte evapotranspiration associee a des temperatures plus chaudes, ainsi que des effets mineurs de la pollution de l'air. Le MARA illustre le concept de systemes complexes et de methodologie pour evaluer les facteurs multivaries dans les systemes de croissance des arbres. Le MARA fournit une structure de modele generale qui incorpore des interactions complexes directes et indirectes pour les etudes du systeme arbre et integre de faon quantitative la connaissance et les donnees provenant de differentes disciplines en developpant un nouvel ensemble d'indices, les valeurs de l'indice de base relatif. Des directives detaillees, dependantes de l'habitat, decoulent des resultats du MARA pour l'amenagement et les politiques de conservation a long terme de l'epinette rouge en fonction des changements environnementaux, du changement climatique et de la pollution de l'air dans le parc national des Great Smokey Mountains. [Traduit par la Redaction], Introduction For half a century, red spruce (Picea rubens Sarg.), a commercially and ecologically important boreal tree species, has experienced growth decline and high mortality in eastern North America (McLaughlin [...]

The digital divide has loomed as a public policy issue for over a decade. Yet, a theoretical account for the effects of the digital divide is currently lacking. This study [...]

Aldosterone and corticosterone bind to mineralocorticoid (MR) and glucocorticoid receptors (GR), which, upon ligand binding, are thought to translocate to the cell nucleus to act as transcription factors. Mineralocorticoid selectivity is achieved by the 11 [beta]-hydroxysteroid dehydrogenase type 2 (11[beta]-HSD2) that inactivates 1l[beta]-hydroxy glucocorticoids. High expression levels of 11[beta]-HSD2 characterize the aldosterone-sensitive distal nephron (ASDN), which comprises the segment-specific cells of late distal convoluted tubule (DCT2), connecting tubule (CNT), and collecting duct (CD). We used MR- and GR-specific antibodies to study localization and regulation of MR and GR in kidneys of rats with altered plasma aldosterone and corticosterone levels. In control rats, MR and GR were found in cell nuclei of thick ascending limb (TAL), DCT, CNT, CD cells, and intercalated cells (IC). GR was also abundant in cell nuclei and the subapical compartment of proximal tubule (PT) cells. Dietary NaCI loading, which lowers plasma aldosterone, caused a selective removal of GR from cell nuclei of 11[beta]-HSD2-positive ASDN. The nuclear localization of MR was unaffected. Adrenalectomy (ADX) resulted in removal of MR and GR from the cell nuclei of all epithelial cells. Aldosterone replacement rapidly relocated the receptors in the cell nuclei. In ASDN cells, low-dose corticosterone replacement caused nuclear localization of MR, but not of GR. The GR was redistributed to the nucleus only in PT, TAL, early DCT, and IC that express no or very little 11 [beta]-HSD2. In ASDN cells, nuclear GR localization was only achieved when corticosterone was replaced at high doses. Thus ligand-induced nuclear translocation of MR and GR are part of MR and GR regulation in the kidney and show remarkable segment- and cell type-specific characteristics. Differential regulation of MR and GR may alter the level of heterodimerization of the receptors and hence may contribute to the complexity of corticosteroid effects on ASDN function. aldosterone; corticosterone; 11[beta]-hydroxysteroid dehydrogenase type 2 doi: 10.1152/ajprenal.00437.2010

To authenticate to the full-text of this article, please visit this link: http://dx.doi.org/10.1111/j.1600-0706.2009.18104.x Byline: Stuart R. Borrett, Stuart J. Whipple, Bernard C. Patten Abstract: Indirect effects are important components of ecological and evolutionary interactions that may maintain biodiversity, enable or inhibit invasive species, and challenge ecosystem assessment and management. A central hypothesis of Network Environ Analysis (NEA), one type of ecological network analysis, is that indirect flows tend to dominate direct flows in ecosystem networks of conservative substance exchanges. However, current NEA methods assume that these ecosystems are stationary (i.e. time invariant exchange rates), which is unlikely to be true for many ecosystems for interesting time and space scales. For the work reported here, we investigated the sensitivity of the dominance of indirect effects hypothesis to the stationary modeling assumption by determining the development rate of indirect effects and flow intensity, as expressed as the number of transfer steps, in thirty-one ecosystem models. We hypothesized that indirect effects develop rapidly in ecological networks, but that they would develop faster in biogeochemically based models than in trophically based models. In contrast, our results show that indirect effects develop rapidly in all thirty-one models examined. In 94% of the models, indirect flows exceeded direct flows by a pathway length of 3. This indicates that ecological systems do not need to maintain a particular configuration for long for indirect effects to dominate. Thus, the dominance of indirect effects hypothesis remains plausible. We also found that biogeochemical models tended to require more of the extended path network than the trophic models to account for 50% and 95% of the total system activity, but that both types of models required more of the power series than is typically considered in engineered systems. These results succinctly illustrate the complexity of ecological systems and help explain why they are challenging to assess and manage. Author Affiliation: (1)Dept of Biology and Marine Biology, Univ. of North Carolina Wilmington, 601. S. College Rd., Wilmington, NC 28403, USA, and Center for Marine Science, Univ. of North Carolina Wilmington, Wilmington, NC 28403, USA (2)Skidaway Inst. of Oceanography, 10 Ocean Science Circle, Savannah, GA 31411, USA (3)Odum School of Ecology, Univ. of Georgia, 140 E. Green St., Athens, GA 30602-2202, USA Article History: Paper manuscript accepted 1 September 2009 Article note: S. R. Borrett, Dept of Biology and Marine Biology, Univ. of North Carolina Wilmington, 601. S. College Rd., Wilmington, NC 28403, USA, and Center for Marine Science, Univ. of North Carolina Wilmington, Wilmington, NC 28403, USA. E-mail: borretts@uncw.edu

Peter Dwyer & Leo Zeilig African Struggles Today: Social Movements Since Independence, Haymarket Books: Chicago, 2012; 260 pp: 9781608461202, $17 (pbk) Peter Dwyer (Ruskin College) and Leo Zeilig (Institute of [...]

McColloch, Jock. South Africa's Gold Mines & the Politics of Silicosis. Suffolk, UK: James Currey, 2012. In South Africa's Gold Mines & the Politics of Silicosis, Jock McColloch presents a [...]

Dave Hill Marxist Essays on Neoliberalism, Class, 'Race', Capitalism and Education, Institute for Education Policy Studies, Brighton, 2013; 204 pp.; 9780952204220, 15 [pounds sterling]. This small volume is a compilation [...]

The cortical collecting duct (CCD) plays a key role in regulated [K.sup.+] secretion, which is mediated mainly through renal outer medullary [K.sup.+] (ROMK) channels located in the apical membrane. However, the mechanisms of the regulation of urinary [K.sup.+] excretion with regard to [K.sup.+] balance are not well known. We took advantage of a recently established mouse CCD cell line (mCC[D.sub.c11]) to investigate the regulation of [K.sup.+] secretion by mineralocorticoid and [K.sup.+] concentration. We show that this cell line expresses ROMK mRNA and a barium-sensitive [K.sup.+] conductance in its apical membrane. As this conductance is sensitive to tertiapin-Q, with an apparent affinity of 6 nM, and to intracellular acidification, it is probably mediated by ROMK. Overnight exposure to 100 nM aldosterone did not significantly change the [K.sup.+] conductance, while it increased the amiloride-sensitive [Na.sup.+] transport. Overnight exposure to a high [K.sup.+] (7 mM) concentration produced a small but significant increase in the apical membrane barium-sensitive [K.sup.+] conductance. The mRNA levels of all ROMK isoforms measured by qRT-PCR were not changed by altering the basolateral [K.sup.+] concentration but were decreased by 15-45% upon treatment with aldosterone (0.3 or 300 nM for 1 and 3 h). The paradoxical response of ROMK expression to aldosterone could possibly work as a preventative mechanism to avoid excessive [K.sup.+] loss which would otherwise result from the increased electrogenic [Na.sup.+] transport and associated depolarization of the apical membrane in the CCD. In conclusion, mCC[D.sub.c11] cells demonstrate a significant [K.sup.+] secretion, probably mediated by ROMK, which is not stimulated by aldosterone but increased by overnight exposure to a high [K.sup.+] concentration. cultured mCCD cells; urinary potassium excretion; aldosterone

Terpenoid volatiles are important information molecules that enable pollinators to locate flowers and may protect reproductive tissues against pathogens of herbivores. Inflorescences of grapevine (Vitis vinifera L.) are composed of tiny green flowers that produce an abundance of sesquiterpenoid volatiles. We demonstrate that male flower parts of grapevines are responsible for sesquiterpenoid floral scent formation. We describe temporal and spatial patterns of biosynthesis and release of floral volatiles throughout the blooming of V. vinifera L. cv. Cabernet Sauvignon. The biosynthesis of sesquiterpene volatiles, which are emitted with a light-dependent diurnal pattern early in the morning at prebloom and bloom, is localized to anthers and, more specifically, within the developing pollen grains. Valencene synthase (VvValCS) enzyme activity, which produces the major sesquiterpene volatiles of grapevine flowers, is present in anthers. VvValCS transcripts are most abundant in flowers at prebloom stages. Western blot analysis identified VvValCS protein in anthers, and in situ immunolabeling located VvValCS protein in pollen grains during bloom. Histochemical staining, as well as immunolabeling analysis by fluorescent microscopy and transmission electron microscopy, indicated that VvValCS localizes close to lipid bodies within the maturing microspore. anthers | floral scent | flower development | sesquiterpenes | terpenoid biosynthesis

Polycystic kidney diseases result from disruption of the genetically defined program that controls the size and geometry of renal tubules. Cysts which frequently arise from the collecting duct (CD) result from cell proliferation and fluid secretion. From mCC[D.sub.c11] cells, a differentiated mouse CD cell line, we isolated a clonal subpopulation (mCCD-N21) that retains morphogenetic capacity. When grown in three-dimensional gels, mCCD-N21 cells formed highly organized tubular structures consisting of a palisade of polarized epithelial cells surrounding a cylindrical lumen. Subsequent addition of cAMP-elevating agents (forskolin or cholera toxin) or of membrane-permeable cAMP analogs (CPT-cAMP) resulted in rapid and progressive dilatation of existing tubules, leading to the formation of cystlike structures. When grown on filters, mCCD-N21 cells exhibited a high transepithelial resistance as well as aldosterone- and/or vasopressin-induced amiloride-sensitive and -insensitive current. The latter was in part inhibited by [Na.sup.+]-[K.sup.+]-2[Cl.sup.-] cotransporter (bumetanide) and chloride channel (NPPB) inhibitors. Real-time PCR analysis confirmed the expression of NKCC1, the ubiquitous [Na.sup.+]-[K.sup.+]-2[Cl.sup.-] cotransporter and cystic fibrosis transmembrane regulator (CFTR) in mCCD-N21 cells. Tubule enlargement and cyst formation were prevented by inhibitors of [Na.sup.+]-[K.sup.+]-2[Cl.sup.-] cotransporters (bumetanide or ethacrynic acid) or CFTR (NPPB or CFFR inhibitor-172). These results further support the notion that cAMP signaling plays a key role in renal cyst formation, at least in part by promoting chloride-driven fluid secretion. This new in vitro model of tubule-to-cyst conversion affords a unique opportunity for investigating the molecular mechanisms that govern the architecture of epithelial tubes, as well as for dissecting the pathophysiological processes underlying cystic kidney diseases. tubulogenesis; polycystic kidney; ADPKD

Die build up (DBU) is a common problem encountered during extrusion of polymers where material accumulates around the die exit and may cause defects in the surface of the product. This study was initiated to better understand the fundamental relationships between DBU and die swell. The study was conducted on a strand die extrusion system using an ethylene-octene polyolefin elastomer resin. This study demonstrated that die swell is not a root cause of DBU. It was shown that at constant shear rate, increasing the die L/D ratio results in an increase in DBU, while die swell decreases. The important variables influencing DBU for the resin used in this study were: the shear rate or shear stress in capillary portion of the die, the nominal residence time that the resin is exposed to the high shear stress in the die capillary, and the concentration of oligomers present in the resin or generated during processing. These data support the conclusion that DBU is due to the shear-induced migration of oligomeric species in the polymer to the die surface. Higher shear rates and stresses in the die promote this migration and result in a higher concentration of oligomeric species near the die wall. POLYM. ENG. SCI., 49:333-343, 2009, © 2008 Society of Plastics Engineers, INTRODUCTION Die face build up is a common problem encountered in polymer processing. During extrusion, material accumulates around the die exit and is referred to as 'die face build-up,' die [...]

This paper considers the design of a minimax test for two hypotheses where the actual probability densities of the observations are located in neighborhoods obtained by placing a bound on the relative entropy between actual and nominal densities. The minimax problem admits a saddle point which is characterized. The robust test applies a nonlinear transformation which flattens the nominal likelihood ratio in the vicinity of one. Results are illustrated by considering the transmission of binary data in the presence of additive noise. Index Terms--Kullback-Leibler divergence, least favorable densities, min-max problem, robust hypothesis testing, saddle point.

When various wild strains of Penicillium lanosum and Aspergillus niger were placed in the same mild laboratory environment, their frequencies of new spontaneous mutations were clearly related to whether they had been isolated from a region of high or low microclimatic stress. In the mild environment, the total frequencies of conidial color and morphological mutations in P. lanosum, summed over all relevant loci, ranged from 0.29% to 2.4% for six strains from the north-facing, less stressful 'European' slope (ES/NFS) of 'Evolution Canyon' I, compared with 6.5-11.6% for five strains from the south-facing 'African' slope (AS/SFS), which is a much more stressful environment, being harsher, drier, more fluctuating in temperature, and receiving up to eight times more UV radiation than the opposite slope. The corresponding figures for A. niger were 0.42-1.50% for three strains from the ES/NFS and 2.3-4.9% for six strains from the AS/SFS. The more mutagenic environment of the AS/SFS than of the ES/NFS means that, in Evolution Canyon, the mutation frequency differences between the very stressful environment and the less stressful environment are probably even larger than the 4- and 6-fold differences found here in a mild laboratory environment. The evidence from these two filamentous fungi, which have no sexual cycle, is that there are inherited differences in spontaneous mutation rates according to the levels of stress in the environment, and this feature may well be adaptive. Evolution Canyon | is at Nahal Oren, Mount Carmel, Israel. adaptation | Aspergillus niger | mutation rates | Penicillium lanosum

Transepithelial alveolar sodium ([Na.sup.+]) transport mediated by the amiloride-sensitive epithelial sodium channel (ENaC) constitutes the driving force for removal of fluid from the alveolar space. To define the role of the [beta]-ENaC subunit in vivo in the mature lung, we studied a previously established mouse strain harboring a disruption of the [beta]-ENaC gene locus resulting in low levels of [beta]-ENaC mRNA expression. Real-time RT-PCR experiments confirmed that [beta]-ENaC mRNA levels were decreased by >90% in alveolar epithelial cells from homozygous mutant (m/m) mice. [beta]-ENaC protein was undetected in lung homogenates from m/m mice by Western blotting, but [alpha]- and [gamma]-ENaC proteins were increased by 83% and 45%, respectively, compared with wild-type (WT) mice. At baseline, [Na.sup.+]-driven alveolar fluid clearance (AFC) was significantly reduced by 32% in m/m mice. Amiloride at the concentration 1 mM inhibited AFC by 75% and 34% in WT and m/m mice, respectively, whereas a higher concentration (5 mM) induced a 75% inhibition of AFC in both groups. The [[beta].sub.2]-agonist terbutaline significantly increased AFC in WT but not in m/m mice. These results show that despite the compensatory increase in [alpha]- and [gamma]-ENaC protein expression observed in mutant mouse lung, low expression of [beta]-ENaC results in a moderate impairment of baseline AFC and in decreased AFC sensitivity to amiloride, suggesting a possible change in the stoichiometry of ENaC channels. Finally, adequate [beta]-ENaC expression appears to be required for AFC stimulation by [[beta].sub.2]-agonists. pneumocytes; alveolar sodium transport; amiloride; cation channels

In this paper, we describe a blind calibration method for timing mismatches in a four-channel time-interleaved analog-to-digital converter (ADC). The proposed method requires that the input signal should be slightly oversampled. This ensures that there exists a frequency band around the zero frequency where the Fourier transforms of the four ADC subchannels contain only three alias components, instead of four. Then the matrix power spectral density (PSD) of the ADC subchannels is rank deficient over this frequency band. Accordingly, when the timing offsets are known, we can construct a filter bank that nulls the vector signal at the ADC outputs. We employ a parametrization of this filter bank to develop an adaptive null steering algorithm for estimating the ADC timing offsets. The null steering filter bank employs seven fixed finite-impulse response filters and three unknown timing offset parameters which are estimated by using an adaptive stochastic gradient technique. A convergence analysis is presented for the blind calibration method. Numerical simulations for a bandlimited white noise input and for inputs containing several sinusoidal components demonstrate the effectiveness of the proposed technique. Index Terms--Adaptive null steering filter bank, blind calibration, convergence of adaptive algorithms, Farrow structure, time-interleaved analog-to-digital converter (ADC).

In this paper, we describe a blind calibration method for gain and timing mismatches in a two-channel time-interleaved low-pass analog-to-digital converters (ADC). The method requires that the input signal should be slightly oversampled. This ensures that there exists a frequency band around the zero frequency where the Fourier transforms of the ADC subchannels are alias free. Low-pass filtering the ADC subchannels to this alias-free band reduces the blind calibration problem to a conventional gain and time delay estimation problem for an unknown signal in noise. An adaptive filtering structure with three fixed FIR filters and two adaptive gain and delay parameters is employed to achieve the calibration. A convergence analysis is presented for the blind calibration technique. Numerical simulations for a bandlimited white noise input and for inputs containing several sinusoidal components demonstrate the effectiveness of the proposed method. Index Terms--Adaptive time delay estimation, blind calibration, convergence of adaptive algorithms, Farrow structure, time-interleaved low-pass analog-to-digital converter (ADC).

A study considers a robust mean-square-error (MSE) equalizer for multiple-input-output (MIMO) communications systems with imperfect channel and noise information at the receiver. Simulation results are presented to demonstrate the MSE and bit error rate (BER) performance of robust equalizer when applied to the least favorable channel model.

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.joep.2005.08.005 Byline: Bernard C. Beaudreau Keywords: Identity; Culture; Self-actualization; Humanistic psychology Abstract: Drawing from humanistic psychology, this paper presents an identity-based model of consumer behavior, and uses it to examine various aspects of culture and cultural policy. Specifically, the consumer's problem is modelled as a process of self-actualization over multiple ideal and actual identities (personal constructs), each of which depreciates as a result of information entropy. To restore identities, consumers invest in identity-based information in the form of cultural goods/services/activities. The resulting theory of consumer behavior is used to examine the optimality of various policy measures such as the cultural exception clauses in international trade agreements, UNESCO's Convention on Cultural Diversity, and subsidies and grants in the cultural sector. Author Affiliation: Department of Economics, Universite Laval, Quebec, Canada G1K 7P4 Article History: Received 1 October 2004; Revised 6 August 2005; Accepted 20 August 2005 Article Note: (footnote) [star] The author wishes to acknowledge funding from the Quebec Ministere des relations internationales, and to thank Ivan Bernier, David Robinson, Peter Earl, and an anonymous referee for useful comments on earlier drafts.

Maliseet is one of many Canadian aboriginal languages that are projected to become extinct within the next twenty years. This article examines the events surrounding Maliseet language instruction that contributed to enactments of resistive strategies that corresponded to varieties of power relations--a process I call aboriginality. The local acts of resistance are situated in the Canadian nation-state ideology of 'two founding cultures.' I argue the local acts of resistance challenge local asymmetrical power relations while also addressing nation-state ideologies of dominance and coercion. Initially, the focus of resistance was confined to local domains, but over a period of three years, resistive strategies changed to confront global dominance and coercion. I argue the implications of such shifts in strategies and scales of resistance reflect an 'aboriginal social imaginary,' which holds promise for the survival of aboriginal languages as well as meaningful participation in the 'modern social imaginary' called modernity. Key Words: aboriginality, modernity, resistance, Maliseet language, Canada

A study analyzing the impact of culture on economic behavior patterns of consumers that are oriented for establishing and maintaining an identity is presented.

Past research on vibration energy harvesting has focused primarily on the use of magnets or piezoelectric materials as the basis of energy transduction, with few experimental studies implementing variable-capacitance-based scavenging. In contrast, this paper presents the design and demonstration of a variable-capacitance vibration energy harvester that combines an asynchronous diode-based charge pump with an inductive energy flyback circuit to deliver 1.8 [micro]W to a resistive load. A cantilever beam variable capacitor with a 650-pF dc capacitance and a 348-pF zero-to-peak ac capacitance, formed by a 43.56 [cm.sup.2] spring steel top plate attached to an aluminum base, drives the charge pump at its out-of-plane resonant frequency of 1.56 kHz. The entire harvester requires only one gated MOSFET for energy flyback control, greatly simplifying the clocking scheme and avoiding synchronization issues. Furthermore, the system exhibits a startup voltage requirement below 89 mV, indicating that it can potentially be turned on using just a piezoelectric film. Index Terms--Variable-capacitance-based energy conversion, vibration energy harvesting, vibration energy scavenging.

The feasible set of power injections for the constrained power flow equations is nonconvex when practical transmission capacity and bus voltage limits are imposed. The projection onto the space of active power injections may be 'close' to convex, but this is not sufficient to guarantee revenue adequacy for the settlement of financial transmission rights. Index Terms--Convexity, financial transmission rights (FTRs), optimization methods, power flow analysis, power system economics.

A blind maximum-likelihood equalization algorithm is described and its convergence behavior is analyzed. Since the algorithm employs the Viterbi algorithm (VA) to execute the expectation step of the expectation-maximization (EM) iteration, we call it the expectation-maximization Viterbi algorithm (EMVA). An EMVA-based blind channel-acquisition technique which achieves a high global convergence probability is developed. The performance of the method is evaluated via numerical simulations under static and fading channel conditions. Index Terms--Blind equalization, expectation-maximization (EM) algorithm, expectation-maximization Viterbi algorithm (EMVA), Rayleigh fading channel, Ricean fading channel, Viterbi algorithm (VA).

A blind maximum likelihood equalization method is proposed for frequency selective fast fading Ricean channels. This method employs the expectation-maximization Viterbi algorithm (EMVA) developed in [1] for blind channel estimation and signal detection. Since the Viterbi algorithm (VA) is used to execute the E-phase of an expectation-maximization (EM) iteration, it requires that the observed sequence can be modelled as a finite-state hidden Markov process. We develop a hidden Markov model for frequency selective fast fading Ricean channels, so that the observed process can be viewed as the noisy output of a finite state machine (FSM), to which the VA is applicable. The EMVA is then employed to obtain a blind maximum likelihood estimate of the specular part of the channel and, for one special case, of a noise parameter measuring the total power of the additive and multiplicative channel noise components. Simulation results are presented which show that the EMVA achieves an accurate estimate of the channel specular part and has an error rate performance close to that of the maximum likelihood detector based on true parameters for the given FSM model. Index Terms--Blind equalization, expectation-maximization (EM) algorithm, Rayleigh fading channel, Ricean fading channel, Viterbi algorithm (VA).

In adult cortical tissue, recruitment of GABAergic inhibition prevents the progression of synchronous population discharges to epileptic activity. However, at early developmental stages, GABA is excitatory and thus unable to fulfill this role. Here, we report that retrograde signaling involving endocannabinoids is responsible for the homeostatic control of synaptic transmission and the resulting network patterns in the immature hippocampus. Blockade of cannabinoid type 1 (CB1) receptor led to epileptic discharges, whereas overactivation of CB1 reduced network activity in vivo. Endocannabinoid signaling thus is able to keep population discharge patterns within a narrow physiological time window, balancing between epilepsy on one side and sparse activity on the other, which may result in impaired developmental plasticity. Disturbing this delicate balance during pregnancy in either direction, e.g., with marijuana as a CB1 agonist or with an antagonist marketed as an antiobesity drug, can have profound consequences for brain maturation even in human embryos. endocannabinoid | epilepsy | interneurons | neonates | drug abuse

This paper explores the use of a new technique, the probabilistic collocation method (PCM), to enable the evaluation of uncertainty in power system simulations. The PCM allows the uncertainty in transient behavior of power systems to be studied using only a handful of simulations. The relevant theory is outlined here and simple examples are used to illustrate the application of PCM in a power systems setting. In addition, an index for identification of key uncertain parameters, as well as an example with a more realistic power system, are presented. Index Terms--Power system modeling, power system simulation, uncertainty.

A band-limited signal can be recovered from its periodic nonuniformly spaced samples provided the average sampling rate is at least the Nyquist rate. A multirate filter bank structure is used to both model this nonuniform sampling (through the analysis bank) and reconstruct a uniformly sampled sequence (through the synthesis bank). Several techniques for modeling the nonuniform sampling are presented for various cases of sampling. Conditions on the filter bank structure are used to accurately reconstruct uniform samples of the input signal at the Nyquist rate. Several examples and simulation results are presented, with emphasis on forms of nonuniform sampling that may be useful in mixed-signal integrated circuits. Index Terms--Bunched sampling, multirate signal processing, nonuniform sampling, time-interleaved analog-to-digital converters.

Chronic hyperaldosteronism in a transgenic mouse model fails to induce cardiac remodeling and fibrosis under a normal-salt diet. Am J Physiol Renal Physiol 286: F1178-F1184, 2004. First published February 3, 2004; 10.1152/ajprenal.00386.2003.--Primary aldosteronism causes severe hypertension in humans (Conn's syndrome) with cardiac hypertrophy, characterized by a fibrosis more severe than the one observed in patients with essential hypertension. This suggests thai aldosterone by itself may have specific and direct effects on cardiac remodeling through the activation of the cardiac mineralocorticoid receptor. Experimental evidence obtained in studying uninephrectomized rats treated with aldosterone or deoxycorticosterone (DOC) together with salt loading has led to similar conclusions. To examine the direct consequences of chronically elevated aldosterone levels on cardiac pathophysiology, we analyzed a mouse model ([alpha]-epithelial Na channel -/-Tg) that is normotensive under normal-salt diet but exhibits chronic hyperaldosteronism. Sixteenmonth-old transgenic rescue mice that were kept under a regular salt diet that contains a small amount of sodium (0.3% [Na.sup.+]) displayed a compensated PHA-1 phenotype with normal body weight, normal kidney index, normal blood pressure, but 6.3-fold elevated plasma aldosterone levels compared with the age-matched control group. Peripheral resistance of distal colon to aldosterone was shown by a significant decrease of the amiloride-sensitive rectal potential difference, and its diurnal cyclicity was blunted. Despite chronically high plasma aldosterone levels, these animals do not show any evidence of cardiac hypertrophy, remodeling, or fibrosis, using collagen staining and anti-[alpha]-skeletal and [alpha]-smooth actin immunochemical labeling of heart sections. Cardiac fibrosis as seen in DOC- or aldosterone/salttreated animal models is therefore likely to be due to the synergistic effect of salt, aldosterone, and other confounding factors rather than to the elevated circulating aldosterone levels alone. cardiac hypertrophy and fibrosis; epithelial Na channel activity; hypertension

The trans-plasma-membrane electrochemical potential of microaerophilic protists was monitored by the use of voltage-sensitive charged lipophilic fluorophores; of the many available probes, the anionic oxonol dye bis(1,3-dibarbituric acid)-trimethine oxonol [DiBA[C.sub.4](3)] is an example of one which has been successfully employed using fluorescence microscopy, confocal laser-scanning microscopy and flow cytometry. Several microaerophilic protists have been investigated with this dye; these were Giardia intestinalis, Trichomonas vaginalis, Tritrichomonas foetus, Hexamita inflata and Mastigamoeba punctachora. Under conditions where they exhibit normal vitality, these organisms exclude DiBA[C.sub.4](3) by virtue of their maintenance of a plasma-membrane potential (negative inside). Uptake of the fluorophore is indicative of disturbance to this membrane (i.e. by inhibition of pump/leak balance, blockage of channels or generation of ionic leaks), and is indicative of metabolic perturbation or environmental stress. Here, it is shown that oxidative or nitrosative stress depolarizes the plasma membranes of the aforementioned [O.sub.2]-sensitive organisms and allows DiBA[C.sub.4](3) influx. Oxonol uptake thereby provides a sensitive and early indication of plasma-membrane perturbation by agents that may lead to cytotoxicity and eventually to cell death by necrotic or apoptotic pathways.

Given a nominal statistical model, we consider the minimax estimation problem consisting of finding the best least-squares estimator for the least favorable statistical model within a neighborhood of the nominal model. The neighborhood is formed by placing a bound on the Kullback-Leibler (KL) divergence between the actual and nominal models. For a Gaussian nominal model and a finite observations interval, or for a stationary Gaussian process over an infinite interval, the usual noncausal Wiener filter remains optimal. However, the worst case performance of the filter is affected by the size of the neighborhood representing the model uncertainty. On the other hand, standard causal least-squares estimators are not optimal, and a characterization is provided for the causal estimator and the corresponding least favorable model. The causal estimator takes the form of a risk-sensitive estimator with an appropriately selected risk sensitivity coefficient. Index Terms--Kullback-Leibler (KL) divergence, minimax problem, risk-sensitive filtering, robust filtering, saddle point.

Currents through epithelial Na channels (ENaCs) were measured in the cortical collecting tubule (CCT) of mice expressing truncated [beta]-subunits of ENaC, reproducing one of the mutations found in human patients with Liddle's syndrome. Tubules were isolated from mice homozygous for the Liddle mutation (L/L) and from wild-type (WT) littermates. Amilo-ride-sensitive currents ([I.sub.Na]) from single cells were recorded under whole cell clamp conditions. CCTs from mice kept under control conditions and fed a diet with normal levels of Na had very small [I.sub.NaS] (WT: 18 [+ or -] 13 pA; L/L: 22 [+ or -] 8 pA at [V.sub.m] = -100 mV) that were not different in WT and L/L animals. However, the L/L mice had much larger currents when the animals were fed a low-Na diet (WT: 256 [+ or -] 127 pA; L/L: 1,820 [+ or -] 330 pA) or infused with aldosterone (WT: 285 [+ or -] 63 pA; L/L: 1,600 [+ or -] 280 pA). Currents from L/L mice were also larger when animals were pretreated with a high-K diet but not when the CCTs were stimulated in vitro with 8-CTP-cAMP. Noise analysis of amiloride-induced fluctuations in [I.sub.Na] showed that single-channel currents at [V.sub.m] = 0 mV were slightly smaller in L/L mice (WT: 0.33 pA; L/L: 0.24 pA). This difference could be attributed to a decrease in driving force since current-voltage analysis indicated that intracellular Na was increased in the L/L animals. Analysis of spontaneous channel noise indicated that the open probability was similar in the two genotypes (WT: 0.77; L/L: 0.80). Thus the increase in whole cell current is attributed to a difference in the density of conducting channels. kidney; sodium transport; aldosterone; hypertension; amiloride

Byline: Bernard C. Jiang (1), Chi-Hsing Hsu (1) Keywords: Product development; concurrent engineering; fuzzy logic; multiple attribute decision making Abstract: A manufacturability evaluation decision model is formulated and analyzed based on fuzzy logic and multiple attribute decision-making under the concurrent engineering environment. The study emphasizes on the treatment of the linguistic and vagueness at the early product development stage. The study also considers the function integration of the total life cycle of a product. Hence, the integrated decision model covers the multi-level, multi-goal requirements of the products. Multiple criteria such as the goal space, the decision space, the function space, the development (i.e., product &amp process design) space, and the activity space, are then applied under different analysis of decision-making methods. For instances, the fuzzy multiple attribute decision-making (FMADM) combined with activity-based costing (ABC) can be used in the activity decision space. The fuzzy logic decision model can be applied in the goal decision space. The results of this study point out the importance of early decision making capability. An example of a high-pressure vessel is provided to demonstrate the proposed model for evaluating the manufacturability. Author Affiliation: (1) Department of Industrial Engineering and Management, Yuan Ze University, Chung-Li, 32026, Taiwan, ROC Article History: Registration Date: 05/10/2004

In the semiconductor industry, IC marking error remains a problem. The objective of this study is to identify IC marking using gray relational analysis. The gray theorem determines the gray relational grades of all of the selected factors by choosing the highest gray relational grade, even under incomplete information circumstances. In an IC marking identification procedure, an image is rotated and segmented first. Second, thresholding and thinning operations are applied to reduce the calculation complexity and extract features from the segmented image. Finally, the gray relational analysis method is applied to inspect the IC markings. The identification rate reaches 97.5%. As compared to traditional methods, there are three advantages in gray relational analysis: 1) No large amount of data is needed; 2) No specific statistical data distribution is required; and 3) There is no requirement for the independency of the factors to be considered. It is an easy and practical method in the field of IC marking inspection. Index Terms--Gray system theory, IC marking, inspection, machine vision.

Sodium balance is maintained by the precise regulation of the activity of the epithelial sodium channel (ENaC) in the kidney. We have recently reported an extracellular activation of ENaC-mediated sodium transport ([I.sub.Na]) by a GPI-anchored serine protease (mouse channel-activating protein, mCAP1) that was isolated from a cortical collecting duct cell line derived from mouse kidney. In the present study, we have identified two additional membrane-bound serine proteases (mCAP2 and mCAP3) that are expressed in the same cell line. We show that each of these proteases is able to increase [I.sub.Na] 6-10-fold in the Xenopus oocyte expression system. [I.sub.Na] and the number (N) of channels expressed at the cell surface (measured by binding of a FLAG monoclonal [I.sup.125]-radioiodinated antibody) were measured in the same oocyte. Using this assay, we show that mCAP1 increases [I.sub.Na] 10-fold (P < 0.001) but N remained unchanged (P = 0.9), indicating that mCAP1 regulates ENaC activity by increasing its average open probability of the whole cell (wc[P.sub.o]). The serum- and glucocorticoid-regulated kinase (Sgk1) involved in the aldosterone-dependent signaling cascade enhances [I.sub.Na] by 2.5-fold (P < 0.001) and N by 1.6-fold (P < 0.001), indicating a dual effect on N and wc[P.sub.o]. Compared with Sgk1 alone, coexpression of Sgk1 with mCAP1 leads to a ninefold increase in [I.sub.Na] (P < 0.001) and 1.3-fold in N (P < 0.02). Similar results were observed for mCAP2 and mCAP3. The synergism between CAPs and Sgk1 on [I.sub.Na] was always more than additive, indicating a true potentiation. The synergistic effect of the two activation pathways allows a large dynamic range for ENaC-mediated sodium regulation crucial for a tight control of sodium homeostasis. KEY WORDS: epithelial sodium channel * amiloride * serum glucocorticoid-regulated kinase 1 (Sgk1) * aldosterone * NEDD4

We evaluated seropositivity to swine and human H1 influenza viruses in 74 swine farm owners, employees, their family members, and veterinarians in rural south-central Wisconsin, compared with 114 urban Milwaukee, [...]

Design of space-time receivers is discussed. The receivers preserve the whiteness of channel noise while reducing the intersymbol interference (ISI) so that optimum maximum a posteriori (MAP) equalization can be performed on the receiver output.