bluuebunny/crossref_metadata_2025 huggingface dataset:
The BMI of men and not sperm parameters impact on embryo quality and the IVF outcome
Authors: Anifandis G. , Dafopoulos K. , Messini C. I. , Polyzos N. , Messinis I. E.
Published: September 2012

It has been reported that increased body mass index (BMI) of men influences fecundity but it is not clear if it impacts on sperm parameters. Whether or not BMI of men influence sperm parameters and subsequently in vitro fertilization (IVF) result remains to be clarified. The aim of the present study was primarily to investigate the relationship between the BMI of men and sperm parameters (volume, concentration and motility) and whether or not it impacts on embryo quality and IVF outcome. Secondly, to investigate the impact of BMI of both men and women, in combination with their age, on IVF result. Three hundred and one couples were categorized according to their BMI. Group 1 (n = 64, both men and women had BMI l ≤ 25 kg/m2), group 2 (n = 79, both men and women had BMI > 25 kg/m2), group 3 (n = 142, men had BMI > 25 kg/m2and their wives had BMI ≤ 25 kg/m2) and group 4 (n = 16, men had BMI ≤ 25 kg/m2 and their wives had BMI > 25 kg/m2). Overall (n = 301) BMI and age of men did not correlate with sperm parameters. Group 1 and group 4, regardless of the BMI of their women, demonstrated the highest quality of embryos and consequently the highest percentage of pregnancy. Furthermore, the score of the combination of both BMI and age of both men and women resulted in a threshold level of less than 800 with a relative high per cent of pregnancy. BMI of men does not correlate with sperm parameters, but influences the quality of produced embryos in such a way that impacts on pregnancy rate.
The importance of iron speciation (Fe+2/Fe+3) in determining mineral assemblages: an example from the high‐grade aluminous metapelites of southeastern Madagascar
Authors: BOGER S. D. , WHITE R. W. , SCHULTE B.
Published: September 2012

Metapelitic granulites from the Anosyen domain of southeastern Madagascar are exposed in three intercalated formations: the Amparihy, Bakika and Ihosy formations. Although mineralogically distinct from each other, the rocks from these formations show very similar bulk‐rock compositions when measured on a FeT basis. The preserved mineral assemblages thus do not reflect differences in the ratios of the main rock‐forming oxides (i.e. Al2O3:FeT:MgO), but instead reflect variations in the pre‐metamorphic oxidation state of the protolith rocks. These differences in oxidation state are manifested via differences in iron speciation – either Fe+2 or Fe+3. The relatively reduced rocks of the Amparihy Formation preserve the assemblage bi–sp–sill–g–cd, which contrasts markedly with the mostly garnet and spinel‐absent bi–cd–sill–mt assemblages preserved in the strongly oxidized rocks of the Ihosy Formation. Compositionally intermediate rocks of the Bakika Formation are garnet bearing, but sillimanite‐absent, and contain the assemblage sp–g–cd–mag. Modelling of these rocks in the Na2O–CaO–K2O–FeO–MgO–Al2O3–SiO2–H2O–TiO2–O system suggests that they evolved along a heating and cooling P–T path with only limited decompression accompanying cooling on the retrograde path. Peak temperatures and pressures of ∼880–920 °C and 6–6.5 kbar are inferred for the majority of the Anosyen domain, with slightly lower peak temperatures (∼840 °C) estimated in the extreme northwest of the area. The high‐temperature and relatively low‐pressure nature of metamorphism suggests high geothermal gradients existed during orogenesis, which in southern Madagascar is related to the amalgamation of Gondwana (580–520 Ma). Although metamorphic temperatures may have been augmented via thermal advection from the emplacement of the syn‐ to post‐tectonic Ambalavao suite, the high geothermal gradients nevertheless suggest thin and consequently hot lithosphere existed prior to orogenesis.
Aromatase expression in human peripheral blood leucocytes (PBLs) and in various tissues in primates: studies in elderly humans and cynomolgus monkeys
Authors: Pignatti Elisa , Casarini Livio , Scaltriti Sara , Wistuba Joachim , Schlatt Stefan , Rossi Alessandra , Lachhab Asmaa , Taliani Erica , Carani Cesare , Simoni Manuela
Published: September 2012

Background

Previous analysis of aromatase gene and protein expression in peripheral blood leucocytes (PBLs), studied in children and adults, was extended to elderly subjects. In addition, we assessed whether aromatase expression in PBLs could be used as a parameter of aromatase expression in other tissues, using the cynomolgus monkey as model.

Methods

Real‐time PCR analysis of aromatase gene expression and protein evaluation by Western blot was performed in PBLs of human elderly subjects and in various tissues from cynomolgus monkeys.

Results

No gender‐related difference in CYP19A1 mRNA and protein expression in PBLs from human elderly women and men was found. In elderly male cynomolgus monkeys, CYP19A1 mRNA and protein were expressed in all cells and tissues analysed, with the lowest levels in PBLs but no clear‐cut correlation with other tissues.

Conclusions

Aromatase expression in PBLs in elderly human subjects is not gender‐related and cannot be a surrogate of aromatase expression for other tissues.
EVALUATING MACROECONOMIC FORECASTS: A CONCISE REVIEW OF SOME RECENT DEVELOPMENTS
Authors: Franses Philip Hans , McAleer Michael , Legerstee Rianne
Published: September 2012

Macroeconomic forecasts are frequently produced, widely published, intensively discussed, and comprehensively used. The formal evaluation of such forecasts has a long research history. Recently, a new angle to the evaluation of forecasts has been addressed, and in this review we analyze some recent developments from that perspective. The literature on forecast evaluation predominantly assumes that macroeconomic forecasts are generated from econometric models. In practice, however, most macroeconomic forecasts, such as those from the IMF, World Bank, OECD, Federal Reserve Board, Federal Open Market Committee (FOMC), and the ECB, are typically based on econometric model forecasts jointly with human intuition. This seemingly inevitable combination renders most of these forecasts biased and, as such, their evaluation becomes nonstandard. In this review, we consider the evaluation of two forecasts in which: (i) the two forecasts are generated from two distinct econometric models; (ii) one forecast is generated from an econometric model and the other is obtained as a combination of a model and intuition; and (iii) the two forecasts are generated from two distinct (but unknown) combinations of different models and intuition. It is shown that alternative tools are needed to compare and evaluate the forecasts in each of these three situations. These alternative techniques are illustrated by comparing the forecasts from the (econometric) Staff of the Federal Reserve Board and the FOMC on inflation, unemployment, and real GDP growth. It is shown that the FOMC does not forecast significantly better than the Staff, and that the intuition of the FOMC does not add significantly in forecasting the actual values of the economic fundamentals. This would seem to belie the purported expertise of the FOMC.
Tooth eruption: altered gene expression in the dental follicle of patients with cleidocranial dysplasia
Authors: Dorotheou D. , Gkantidis N. , Karamolegkou M. , Kalyvas D. , Kiliaridis S. , Kitraki E.
Published: September 2012

Dorotheou D., Gkantidis N., Karamolegkou M., Kalyvas D., Kiliaridis S., Kitraki E.  Tooth eruption: altered gene expression in the dental follicle of patients with cleidocranial dysplasia  Orthod Craniofac Res 2013; 16:20–27. © 2012 John Wiley & Sons A/S

Structured Abstract

Objectives –  The dental follicle plays an important role in tooth eruption by providing key regulators of osteogenesis and bone resorption. Patients with cleidocranial dysplasia (CCD) exhibit delayed tooth eruption in combination with increased bone density in the maxilla and mandible, suggesting disturbances in bone remodeling. The aim of this study was to determine the expression of genes relevant for tooth eruption and bone remodeling in the dental follicles of patients with CCD and normal subjects.

Material and Methods –  Thirteen dental follicles were isolated from five unrelated patients with CCD, and fourteen dental follicles were obtained from 10 healthy individuals. All teeth were in the intraosseous phase of eruption. The expression of RANK, RANKL, OPG, and CSF‐1 was determined by quantitative RT‐PCR.

Results –  In patients with CCD, the mRNA levels of RANK, OPG, and CSF‐1 were significantly elevated compared with the control group. Accordingly, the ratios of RANKL/OPG and RANKL/RANK mRNAs were significantly decreased in patients with CCD.

Conclusion –  The observed alterations in the expression and ratios of the aforementioned factors in the dental follicle of CCD individuals suggest a disturbed paracrine signaling for bone remodeling that could be responsible for the impaired tooth eruption seen in these patients.
Effects of Endwall Motion on the Aero-Thermal Performance of a Winglet Tip in a HP Turbine
Authors: Zhou Chao , Hodson Howard , Tibbott Ian , Stokes Mark
Published: September 2012

In a gas turbine, the casing endwall moves relative to the blades. In this paper, numerical methods are first validated using experimental results for a stationary endwall. They are then used to study the effects of endwall motion on the aero-thermal performance of both winglet tips with and without tip film cooling at a tip gap of 1.9% C. The endwall motion imposes a tangential force on the flow. A scraping vortex is formed and the flow pattern within the tip gap changes significantly. The tip leakage mass flow rate that exits the tip gap from the suction side edge reduces by about 42% with endwall motion. Overall, the endwall motion reduces the tip leakage loss by 15%. The flow field downstream of the cascade also changes with endwall motion. With endwall motion, the changed flow pattern within the tip gap significantly changes the distribution of the Nusselt number on the winglet tip. For the winglet tip without tip film cooling, the Nusselt number and the heat load decrease with endwall motion. This is mainly due to the reduction in the tip leakage mass flow ratio, which reduces the leakage velocity over the tip. On the winglet tip with tip film cooling, the cooling effectiveness increases by 9% with endwall motion. Combined with the reduced Nusselt number, the heat flux on the winglet tip with tip film cooling reduces by 31% with endwall motion. The cooling effectiveness on the near tip region of the pressure side remains almost unchanged, however, the heat flux rate in this area reduces. This is because the reduced tip leakage mass flow ratio reduces the Nusselt number. With the moving endwall, the thermal performance of the suction side surface of the blade is affected by the scraping vortex. The effects of endwall motion should be considered during the design of the blade tip.
An Investigation of Treating Adiabatic Wall Temperature as the Driving Temperature in Film Cooling Studies
Authors: Zhao Lei , Wang Ting
Published: September 2012

In film cooling heat transfer analysis, one of the core concepts is to deem film cooled adiabatic wall temperature (Taw) as the driving potential for the actual heat flux over the film-cooled surface. Theoretically, the concept of treating Taw as the driving temperature potential is drawn from compressible flow theory when viscous dissipation becomes the heat source near the wall and creates higher wall temperature than in the flowing gas. But in conditions where viscous dissipation is negligible, which is common in experiments under laboratory conditions, the heat source is not from near the wall but from the main hot gas stream; therefore, the concept of treating the adiabatic wall temperature as the driving potential is subjected to examination. To help investigate the role that Taw plays, a series of computational simulations are conducted under typical film cooling conditions over a conjugate wall with internal flow cooling. The result and analysis support the validity of this concept to be used in the film cooling by showing that Taw is indeed the driving temperature potential on the hypothetical zero wall thickness condition, i.e., Taw is always higher than Tw with underneath (or internal) cooling and the adiabatic film heat transfer coefficient (haf) is always positive. However, in the conjugate wall cases, Taw is not always higher than wall temperature (Tw), and therefore, Taw does not always play the role as the driving potential. Reversed heat transfer through the airfoil wall from downstream to upstream is possible, and this reversed heat flow will make Tw > Taw in the near injection hole region. Yet evidence supports that Taw can be used to correctly predict the heat flux direction and always result in a positive adiabatic heat transfer coefficient (haf). The results further suggest that two different test walls are recommended for conducting film cooling experiments: a low thermal conductivity material should be used for obtaining accurate Taw and a relative high thermal conductivity material be used for conjugate cooling experiment. Insulating a high-conductivity wall will result in Taw distribution that will not provide correct heat flux or haf values near the injection hole.
Speech enhancement using a structured codebook
Authors: Hanumantha Rao Naidu D. , Srinivasan Sriram , Prabhakara Rao G. V.
Published: September 2012

Codebook-based speech enhancement methods that use trained codebooks of speech and noise spectra provide good performance even under non-stationary noise conditions. A drawback, however, is their high computational cost. For every pair of speech and noise codebook vectors, a likelihood score indicating how well that pair matches the observation is computed. In this paper, a method that identifies and performs only relevant likelihood computations by imposing a hierarchical structure on the speech codebook is proposed. The performance of the proposed method is shown to be close to that of the original scheme but at a significantly lower computational cost.
ANALYSIS OF ABSENCE SEIZURE GENERATION USING EEG SPATIAL-TEMPORAL REGULARITY MEASURES
Authors: MAMMONE NADIA , LABATE DOMENICO , LAY-EKUAKILLE AIME , MORABITO FRANCESCO C.
Published: September 2012

Epileptic seizures are thought to be generated and to evolve through an underlying anomaly of synchronization in the activity of groups of neuronal populations. The related dynamic scenario of state transitions is revealed by detecting changes in the dynamical properties of Electroencephalography (EEG) signals. The recruitment procedure ending with the crisis can be explored through a spatial-temporal plot from which to extract suitable descriptors that are able to monitor and quantify the evolving synchronization level from the EEG tracings. In this paper, a spatial-temporal analysis of EEG recordings based on the concept of permutation entropy (PE) is proposed. The performance of PE are tested on a database of 24 patients affected by absence (generalized) seizures. The results achieved are compared to the dynamical behavior of the EEG of 40 healthy subjects. Being PE a feature which is dependent on two parameters, an extensive study of the sensitivity of the performance of PE with respect to the parameters' setting was carried out on scalp EEG. Once the optimal PE configuration was determined, its ability to detect the different brain states was evaluated. According to the results here presented, it seems that the widely accepted model of "jump" transition to absence seizure should be in some cases coupled (or substituted) by a gradual transition model characteristic of self-organizing networks. Indeed, it appears that the transition to the epileptic status is heralded before the preictal state, ever since the interictal stages. As a matter of fact, within the limits of the analyzed database, the frontal-temporal scalp areas appear constantly associated to PE levels higher compared to the remaining electrodes, whereas the parieto-occipital areas appear associated to lower PE values. The EEG of healthy subjects neither shows any similar dynamic behavior nor exhibits any recurrent portrait in PE topography.
PERFORMANCE COMPARISON OF DIFFERENTIAL EVOLUTION AND SOMA ON CHAOS CONTROL OPTIMIZATION PROBLEMS
Authors: SENKERIK ROMAN , DAVENDRA DONALD , ZELINKA IVAN , OPLATKOVA ZUZANA , JASEK ROMAN
Published: September 2012

This paper compares the performance of Differential Evolution (DE) with Self-Organizing Migrating Algorithm (SOMA) in the task of optimization of the control of chaos. The main aim of this paper is to show that evolutionary algorithms like DE are capable of optimizing chaos control, leading to satisfactory results, and to show that extreme sensitivity of the chaotic environment influences the quality of results on the selected EA, construction of cost function (CF) and any small change in the CF design. As a model of deterministic chaotic system, the two-dimensional Henon map is used and two complex targeting cost functions are tested. The evolutionary algorithms, DE and SOMA were applied with different strategies. For each strategy, repeated simulations demonstrate the robustness of the used method and constructed CF. Finally, the obtained results are compared with previous research.
BIFURCATION ANALYSIS OF A DISCRETE-TIME KALDOR MODEL OF BUSINESS CYCLE
Authors: HE XING , LI CHUANDONG , SHU YONGLU
Published: September 2012

This paper reports bifurcation dynamics of a discrete-time Kaldor model of business cycle. By using center manifold theorem and bifurcation theory, it is shown that the model not only undergoes flip bifurcation and Neimark–Sacker bifurcation, but also 1 : 1 resonance of codimension two bifurcation occurs. Some numerical examples are given to support the analytic results.
SYMMETRY AND CONSERVATION LAW CLASSIFICATION AND EXACT SOLUTIONS TO THE GENERALIZED KdV TYPES OF EQUATIONS
Authors: LIU HANZE , LI JIBIN , LIU LEI
Published: September 2012

In this paper, complete geometric symmetry and conservation law classification of the generalized KdV types of equations are investigated. All of the geometric vector fields and second-order multipliers for the equations are obtained, and the corresponding conservation laws of the equations are presented explicitly. These comprise all of the second-order conservation laws for the equations. Furthermore, an analytic method is developed for dealing with the exact solutions to the generalized nonlinear partial differential equations with composite function terms.
PERTURBED BEHAVIOR FOR THE MODEL OF WAVE PROPAGATION IN A NONLINEAR DISPERSIVE NONCONSERVATIVE MEDIA
Authors: YU GUOXIANG , YU JUN
Published: September 2012

As a governing equation of wave propagation in a nonlinear, dispersive and dissipative media, KdV–Burgers type equation has received great attention. In this paper, the dynamical behavior of the generalized KdV–Burgers equation under a periodic perturbation is investigated numerically in detail. It is shown that dynamical chaos can occur when we choose appropriately systematic parameters and initial conditions. Abundant bifurcation structures and different routes to chaos such as period-doubling and inverse period-doubling cascades, intermittent bifurcation and crisis, are found by applying bifurcation diagrams, the Poincaré maps and phase portraits. To characterize chaotic behavior of this system, the spectrum of Lyapunov exponent and Lyapunov dimension of the attractor are also employed.
PERIODIC SOLUTION OF CERTAIN NONLINEAR DIFFERENTIAL EQUATIONS: VIA TOPOLOGICAL DEGREE THEORY AND MATRIX SPECTRAL THEORY
Authors: XIA YONG-HUI
Published: September 2012

The main purpose of this article is to establish the existence and stability of a periodic solution of nonlinear differential equation connected with a problem from mathematical biology. The existence and stability conditions are given in terms of spectral radius of explicit matrices, which are better than conditions obtained by using classic norms. The approaches are based on Mawhin's coincidence degree theory, matrix spectral theory and Lyapunov functional. It should be noted that the new problem appears due to the introduction of Gilpin–Ayala effect. The standard methods used in the previous literature cannot be used to analyze the asymptotic stability of such systems. To handle this problem, two novel techniques should be employed. One is to rescale the system by [Formula: see text], not [Formula: see text]. The other is to analyze the maximal eigenvalue of matrix. In fact, the analytic technique is nontrivial. It is original and very interesting. Finally, some examples and their simulations show the feasibility of our results.
HORSESHOE CHAOS IN A HYBRID PLANAR DYNAMICAL SYSTEM
Authors: FAN QING-JU
Published: September 2012

In this paper, we study the chaotic dynamics of a voltage-mode controlled buck converter, which is typically a switched piecewise linear system. For the two-dimensional hybrid system, we consider a properly chosen cross-section and the corresponding Poincaré map, and show that the dynamics of the system is semi-conjugate to a 2-shift map, which implies the chaotic behavior of this system. The essential tool is a topological horseshoe theory and numerical method.
MEMRISTOR MODEL AND ITS APPLICATION FOR CHAOS GENERATION
Authors: WANG LIDAN , DRAKAKIS EMMANUEL , DUAN SHUKAI , HE PENGFEI , LIAO XIAOFENG
Published: September 2012

This paper contributes to the understanding of memristor operation and its possible application fields through: (a) derivation of a complete mathematical model for the HP memristor which takes into consideration the inter-dependence between memristance, charge and flux along with the boundary and initial conditions of operation; (b) an introduction of detailed charge- and flux-controlled SPICE memristor models realizing the proposed mathematical memristor model; (c) The incorporation of the memristor model in the SPICE realization of a third-order chaotic system where a single HP memristor acts as the nonlinear part of the system. Simulation results are provided to validate the mathematical model and the synthesis and operation of the third-order chaotic system.
(ℤ/2ℤ)4-CROSSED PRODUCTS OF EXPONENT 2
Authors: SIVATSKI A. S.
Published: September 2012

Let k be a field of characteristic distinct from 2, a, a1, a2, a3 ∈ k*, D ∈ 2 Br k, exp D = 2, [Formula: see text]. We prove that D is a sum of 18 quaternion algebras. Also for a field F of certain type we construct a certain function f( ind D) such that D is a sum of f( ind D) quaternions for any D ∈ 2 Br (F).
ACCESS TO INFORMATION IN WORD OF MOUTH MARKETING WITHIN A CELLULAR AUTOMATA MODEL
Authors: KOWALSKA-STYCZEŃ AGNIESZKA , SZNAJD-WERON KATARZYNA
Published: September 2012

We propose a simple microscopic model of consumer behavior in which decisions are made solely on the basis of person to person communication. Within our model we determine which factors are important in word of mouth marketing. We provide both Monte Carlo simulations, as well as mean-field analytical calculations and show that both the average decision time and uncertainty of decision grow nonlinearly with the amount of information up to a certain threshold value.
THEORETICAL STUDY OF THE STEREODYNAMICS OF THEN(4S) + D2→ ND + DREACTION ON THE DMBE SURFACE
Authors: GUO YA-HUI , ZHANG FENG-YUN
Published: September 2012

Utilizing the quasiclassical trajectory method, the product rotational polarization of the reaction N(4S) + D2→ ND + D has been calculated at different collision energies on the DMBE potential energy surface [Poveda LA et al., Phys Chem Chem Phys7:2867, 2005]. The distribution of the angle between k and j′, P(θr), the distribution of dihedral angle denoting k–k′–j′ correlation, P(ϕr), as well as the angular distribution of product rotational vectors in the form of polar plots P(θr, ϕr) are calculated. In addition, the four commonly used polarization-dependent differential cross sections, dσ00/dωt, dσ20/dωt, dσ22+/dωt, and dσ21-/dωtwith ωtbeing the polar coordinates of the product velocity k′, are calculated in the center-of-mass frame. The effects of the collision energy on the product polarization are presented and discussed. In comparison with the result of Yu et al. [Yu YJ et al., Chin Phys B20:123402, 2011], significant isotope effects on the stereodynamics of N(4S) + D2(H2) → ND(H) + D(H) have also been revealed.
THEORETICAL INVESTIGATION ON THE INFLUENCE OF INCORPORATEDNiIITO DISTORTION AND STABILITY OFCuII–AlLAYERED DOUBLE HYDROXIDES
Authors: NI ZHEMING , LI YUAN , YAO PING , XU QIAN , ZHENG LI
Published: September 2012

Based on the density functional theory, the structural information and energetic property of Ni–Cu–Al ternary layered double hydroxides were investigated by periodic lattice calculation as a function of cationic substitution. The results revealed that the incorporated NiIIcould improve the structural stability and crystalline perfection of the material. When the content of Ni increased, the charge of the metal cations would transfer to the hydroxyl groups, and the electronic configuration of CuIIand NiIIwould both change from their ideal states. Therefore, as CuIIcations were progressively replaced by NiII, the distortion of Cu(OH)6and Ni(OH)6octahedra would be weakened by enlarging the four short M–O bonds and shortening the two long ones. What is more, the distorted O–M–O bond angle changed to adapt the variety of M–O bond lengths. As a result, all the M(OH)6octahedra could share their edges more conveniently to format the LDHs structure. At last, we conclude that the averaged length of M–O bond and the electron configuration of the metal cations play a significant role in the synthesis of LDHs materials.
INFLUENCE OF CATION-HETEROATOM (Li+, Na+, ANDK+) INTERACTION ON THE STRUCTURAL AND THERMOCHEMICAL PROPERTIES OF 2′-DEOXYTHYMIDINE NUCLEOSIDE: QTAIM AND NBO ANALYZES
Authors: SHAKOURIAN-FARD MEHDI , FATTAHI ALIREZA
Published: September 2012

Density functional theory (DFT) method and B3LYP/6-311++G(d,p) basis set were used to determine coordination geometries, binding strength, and metal ion affinity (MIA) for interaction of 2′-deoxythymidine (dT) with alkali metal cations including Li+, Na+, and K+. Calculations demonstrated that the interaction of dT with these cations is tri-coordinated η (O2, O4′, O5′). Among these cations, Li+cation exhibited the most tendency for interaction with dT. Cations via their interaction with dT can affect the N-glycosidic bond length, the values of pseudorotation of the sugar ring, the orientation of base unit with respect to sugar ring and the acidity of O5′H, O3′H, and N3H groups in 2′-dT nucleoside. Natural bond orbital (NBO) analysis was performed to calculate the charge transfer and natural population analysis of the complexes. Quantum theory of atoms in molecules (QTAIM) was also applied to determine the nature of interactions. It was shown that in these complexes, (dT- Li+, dT- Na+, and dT- K+), the bonds are an electrostatic (closed-shell) interaction in the nature.
Midventricular Obstructive Hypertrophic Cardiomyopathy during Pregnancy Complicated by Pulmonary Embolism: A Case Report
Authors: Abid Leila , Tounsi Ahmed , Abid Dorra , Hentati Mourad , Kammoun Samir
Published: September 2012

Hypertrophic cardiomyopathy (HCM) with midventricular obstruction (MVO) is a rare condition occurring in 1% of HCM patients. It is characterized by asymmetric left ventricular hypertrophy with MVO and elevated intraventricular pressure gradients. Pulmonary embolism has been associated with mid-ventricular obstructive HCM. Briefly, this case presents an unusual clinical scenario where a young pregnant woman suffering from hypertrophic obstructive cardiomyopathy presents with dyspnea hemodynamic compromise related to pulmonary embolism illustrating hemodynamic challenges created by pregnancy and surgery. We concluded that simple measures such as communication between the cardiology and obstetric teams, understanding of the hemodynamic changes, anesthetic planning, and monitoring were paramount for the success in our patient.
The Prevalence of Visual Impairment in Older Adults in Mainland China: A Systematic Review and Meta-Analysis
Authors: Cheng Jin-Wei , Cheng Shi-Wei , Cai Ji-Ping , Li You , Wei Rui-Li
Published: September 2012

Purpose: This paper presents estimates of the prevalence of blindness and low vision among older adults over 50 years of age in mainland China. Methods: All primary reports of population-based studies that reported the prevalence or incidence of visual impairment among older populations in mainland China were identified. Twenty-four population-based studies were included in this systematic review. Blindness is defined as visual acuity of less than 3/60, or a corresponding visual-field loss to less than 10 degrees in the better eye with the best possible correction; low vision is defined as visual acuity of less than 6/18, but equal to or better than 3/60 in the better eye with the best possible correction. The pooled prevalence estimates of blindness and low vision were calculated assuming a random-effects model. Relative odds with 95% confidence intervals (95% CIs) were calculated, stratified by methodological and socioeconomic variables. Results: The overall pooled prevalence of blindness was 1.7% (95% CI 1.4–2.1). The results of the meta-regression showed the significance of a predictor variable: geographic region. The blindness rates per 100 older adults in various regions were 1.4 (0.9–2.0) in East China, and 1.4 (1.0–2.0) in Central China and 2.5 (1.9–3.2) in Western China. The overall pooled prevalence of low vision was 4.1% (3.4–5.1) and the independent pooled prevalence rates stratified by geographic region were 3.6% (2.6–5.1) in East China, 3.6% (2.4–5.2) in Central China and 5.2% (3.6–7.4) in Western China. Conclusions: Blindness or low vision affects approximately 5.8% Chinese adults older than 50 years. The prevalence of visual impairment, and especially blindness, vary greatly by the developmental status of geographic region.
Electroreception in Elasmobranchs: Sawfish as a Case Study
Authors: Wueringer Barbara E.
Published: September 2012

The ampullae of Lorenzini are the electroreceptors of elasmobranchs. Ampullary pores located in the elasmobranch skin are each connected to a gel-filled canal that ends in an ampullary bulb, in which the sensory epithelium is located. Each ampulla functions as an independent receptor that measures the potential difference between the ampullary pore opening and the body interior. In the elasmobranch head, the ampullary bulbs of different ampullae are aggregated in 3–6 bilaterally symmetric clusters, which can be surrounded by a connective tissue capsule. Each cluster is innervated by one branch of the anterior lateral line nerve (ALLN). Only the dorsal root of the ALLN carries electrosensory fibers, which terminate in the dorsal octavo-lateral nucleus (DON) of the medulla. Each ampullary cluster projects into a distinctive area in the central zone of the DON, where projection areas are somatotopically arranged. Sharks and rays can possess thousands of ampullae. Amongst other functions, the use of electroreception during prey localization is well documented. The distribution of ampullary pores in the skin of elasmobranchs is influenced by both the phylogeny and ecology of a species. Pores are grouped in distinct pore fields, which remain recognizable amongst related taxa. However, the density of pores within a pore field, which determines the electroreceptive resolution, is influenced by the ecology of a species. Here, I compare the pore counts per pore field between rhinobatids (shovelnose rays) and pristids (sawfish). In both groups, the number of ampullary pores on the ventral side of the rostrum is similar, even though the pristid rostrum can comprise about 20% of the total length. Ampullary pore numbers in pristids are increased on the upper side of the rostrum, which can be related to a feeding strategy that targets free-swimming prey in the water column. Shovelnose rays pin their prey onto the substrate with their disk, while repositioning their mouth for ingestion and thus possess large numbers of pores ventrally around the mouth and in the area between the gills.
Clinimetrics and Clinical Psychometrics: Macro- and Micro-Analysis
Authors: Tomba Elena , Bech Per
Published: September 2012

Background: Clinimetrics was introduced three decades ago to specify the domain of clinical markers in clinical medicine (indexes or rating scales). In this perspective, clinical validity is the platform for selecting the various indexes or rating scales (macro-analysis). Psychometric validation of these indexes or rating scales is the measuring aspect (micro-analysis). Methods: Clinical judgment analysis by experienced psychiatrists is included in the macro-analysis and the item response theory models are especially preferred in the micro-analysis when using the total score as a sufficient statistic. Results: Clinical assessment tools covering severity of illness scales, prognostic measures, issues of co-morbidity, longitudinal assessments, recovery, stressors, lifestyle, psychological well-being, and illness behavior have been identified. Conclusion: The constructive dialogue in clinimetrics between clinical judgment and psychometric validation procedures is outlined for generating developments of clinical practice in psychiatry.
Electrotransformation and Expression of Cellulase Genes in Wild-Type Lactobacillus reuteri
Authors: Li Wang , Yang Ming-Ming , Zhang Guang-Qin , He Wan-Ling , Li Yuan-Xiao , Chen Yu-Lin
Published: September 2012

Two cellulase genes, Cel15 and Cel73, were amplified from Bacillus subtilis genome DNA in a previous study. Two integrative vectors, pLEM4153 and pLEM4154, containing the genes Cel15 and Cel73, respectively, were constructed and successfully electroporated into the wild-type Lactobacillus reuteri which was isolated from chick guts through an optimized procedure. Two recombinant L. reuteri were selected from a Man, Rogosa, and Sharp (MRS) plate with 10 µg/ml erythromycin, and named L. reuteri XNY-Cel15 and L. reuteri XNY-Cel73, respectively. To verify the transcription and expression of the two cellulase genes in the recombinant L. reuteri strains, the mRNA relative quantity (RQ) and the cellulase activity were determined. The mRNA RQ of Cel15 in L. reuteri XNY-Cel15 is 1,8849.5, and that of Cel73 in L. reuteri XNY-Cel73 is 1,388, and the cellulase activity of the modified MRS broth cultured with L. reuteri XNY-Cel15 was 0.158 U/ml, whereas that with L. reuteri XNY-Cel73 was 0.15 U/ml.
Statin Upregulates the Expression of Klotho, an Anti-Aging Gene, in Experimental Cyclosporine Nephropathy
Authors: Yoon Hye Eun , Lim Sun Woo , Piao Shang Guo , Song Ji-Hyun , Kim Jin , Yang Chul Woo
Published: September 2012

Background: We recently reported that long-term cyclosporine (CsA)-induced oxidative stress is associated with decreased expression of klotho, an anti-aging gene. This study evaluated whether the antioxidant effect of statin might upregulate klotho expression in CsA-induced renal injury. Methods: Two separate experiments were performed. First, the dose-dependent effect of statin on klotho expression was evaluated in normal mouse kidneys. Second, the effect of statin on klotho expression was evaluated in experimental chronic CsA nephropathy in mice. We performed immunohistochemistry and immunoblotting for klotho, Forkhead box O transcription factors [FoxOs; phosphorylated FoxO1 (p-FoxO1) and FoxO3a (p-FoxO3a)] and their target molecules, manganese superoxide dismutase (MnSOD), Bim and hemeoxygenase-1. Results: Statin treatment upregulated klotho expression in a dose-dependent manner in the normal mouse kidney and alleviated the decrease in klotho expression in kidneys exhibiting CsA nephropathy. CsA administration increased p-FoxO1 expression and decreased p-FoxO3a expression, whereas concurrent statin treatment reversed these changes, increased the expression of the antioxidant enzymes MnSOD and hemeoxygenase-1 and decreased the expression of the pro-apoptotic protein Bim. Conclusion: Statin-mediated upregulation of klotho expression and differential regulation of FoxO expression promote resistance to CsA-induced oxidative stress.
Relevance of the ACTN4 Gene in African-Americans with Non-Diabetic End-Stage Renal Disease
Authors: Bostrom Meredith A. , Perlegas Peter , Lu Lingyi , Hicks Pamela J. , Hawkins Greg , Ng Maggie C.Y. , Langefeld Carl D. , Freedman Barry I. , Bowden Donald W.
Published: September 2012

Background: African-Americans (AAs) are predisposed to non-diabetic (non-DM) end-stage renal disease (ESRD), and studies have shown a genetic component to this risk. Rare mutations in ACTN4 (α-actinin-4), an actin-binding protein expressed in podocytes, cause familial focal segmental glomerulosclerosis. Methods: We assessed the contribution of coding variants in ACTN4 to non-DM ESRD risk in AAs. Nineteen exons, 2,800 bases of the promoter and 392 bases of the 3′ untranslated region of ACTN4 were sequenced in 96 AA non-DM ESRD cases and 96 non-nephropathy controls (384 chromosomes). Sixty-seven single-nucleotide polymorphisms (SNPs) including 51 novel SNPs were identified. The SNPs comprised 33 intronic, 21 promoter, 12 exonic, and one 3′ variant. Sixty-two of the SNPs were genotyped in 296 AA non-DM ESRD cases and 358 non-nephropathy controls. Results: One SNP, rs10404257, was associated with non-DM ESRD (p < 1.0E–4, odds ratio, OR = 0.76; confidence interval, CI = 0.59–0.98; additive model). Forty-seven SNPs had minor allele frequencies <5%. These SNPs were segregated into risk and protective SNPs, and each category was collapsed into a single marker, designated by the presence or absence of any rare allele. The presence of any rare allele at a risk SNP was significantly associated with non-DM ESRD (p = 0.001, dominant model). The SNPs with the strongest evidence for association (n = 20) were genotyped in an independent set of 467 non-DM ESRD cases and 279 controls. Although rs10404257 was not associated in this replication sample, when the samples were combined, rs10404257 was modestly associated (p = 0.032, OR = 0.78, CI = 0.63–0.98; dominant model). SNPs were tested for interaction with markers in the APOL1 gene, previously associated with non-DM ESRD in AAs, and rs10404257 was modestly associated (p = 0.0261, additive model). Conclusions: This detailed evaluation of ACTN4 variation revealed limited evidence of association with non-DM ESRD in AAs.
Circulation
Editors' Picks
Authors:   The Editors
Published: September 2012

The following articles are being highlighted as part of
Circulation's
Topic Review series. This series will summarize the most important manuscripts, as selected by the editors, published in
Circulation
and the
Circulation
subspecialty journals. The studies included in this article represent the most read manuscripts published on the topic of health services and outcomes research within the last year.
Projecting “Normals” in a Nonstationary Climate
Authors: Wilks D. S.
Published: September 2012

Climate “normals” are statistical estimates of present and/or near-future climate means for such quantities as seasonal temperature or precipitation. In a changing climate, simply averaging a large number of previous years of data may not be the best method for estimating normals. Here eight formulations for climate normals, including the recently proposed “hinge” function, are compared in artificial- and real-data settings. Although the hinge function is attractive conceptually for representing accelerating climate changes simply, its use is in general not yet justified for divisional U.S. seasonal temperature or precipitation. Averages of the most recent 15 and 30 yr have performed better during the recent past for U.S. divisional seasonal temperature and precipitation, respectively; these averaging windows are longer than those currently employed for this purpose at the U.S. Climate Prediction Center.
Retrieval of Ice Cloud Properties from AIRS and MODIS Observations Based on a Fast High-Spectral-Resolution Radiative Transfer Model
Authors: Wang Chenxi , Yang Ping , Platnick Steven , Heidinger Andrew K. , Baum Bryan A. , Greenwald Thomas , Zhang Zhibo , Holz Robert E.
Published: September 2012

A computationally efficient high-spectral-resolution cloudy-sky radiative transfer model (HRTM) in the thermal infrared region (700–1300 cm−1, 0.1 cm−1 spectral resolution) is advanced for simulating the upwelling radiance at the top of atmosphere and for retrieving cloud properties. A precomputed transmittance database is generated for simulating the absorption contributed by up to seven major atmospheric absorptive gases (H2O, CO2, O3, O2, CH4, CO, and N2O) by using a rigorous line-by-line radiative transfer model (LBLRTM). Both the line absorption of individual gases and continuum absorption are included in the database. A high-spectral-resolution ice particle bulk scattering properties database is employed to simulate the radiation transfer within a vertically nonisothermal ice cloud layer. Inherent to HRTM are sensor spectral response functions that couple with high-spectral-resolution measurements in the thermal infrared regions from instruments such as the Atmospheric Infrared Sounder (AIRS) and Infrared Atmospheric Sounding Interferometer. When compared with the LBLRTM and the discrete ordinates radiative transfer model (DISORT), the root-mean-square error of HRTM-simulated single-layer cloud brightness temperatures in the thermal infrared window region is generally smaller than 0.2 K. An ice cloud optical property retrieval scheme is developed using collocated AIRS and Moderate Resolution Imaging Spectroradiometer (MODIS) data. A retrieval method is proposed to take advantage of the high-spectral-resolution instrument. On the basis of the forward model and retrieval method, a case study is presented for the simultaneous retrieval of ice cloud optical thickness τ and effective particle size Deff that includes a cloud-top-altitude self-adjustment approach to improve consistency with simulations.
The Freshwater System West of the Antarctic Peninsula: Spatial and Temporal Changes
Authors: Meredith Michael P. , Venables Hugh J. , Clarke Andrew , Ducklow Hugh W. , Erickson Matthew , Leng Melanie J. , Lenaerts Jan T. M. , van den Broeke Michiel R.
Published: September 2012

Climate change west of the Antarctic Peninsula is the most rapid of anywhere in the Southern Hemisphere, with associated changes in the rates and distributions of freshwater inputs to the ocean. Here, results from the first comprehensive survey of oxygen isotopes in seawater in this region are used to quantify spatial patterns of meteoric water (glacial discharge and precipitation) separately from sea ice melt. High levels of meteoric water are found close to the coast, due to orographic effects on precipitation and strong glacial discharge. Concentrations decrease offshore, driving significant southward geostrophic flows (up to ~30 cm s−1). These produce high meteoric water concentrations at the southern end of the sampling grid, where collapse of the Wilkins Ice Shelf may also have contributed. Sea ice melt concentrations are lower than meteoric water and patchier because of the mobile nature of the sea ice itself. Nonetheless, net sea ice production in the northern part of the sampling grid is inferred; combined with net sea ice melt in the south, this indicates an overall southward ice motion. The survey is contextualized temporally using a decade-long series of isotope data from a coastal Antarctic Peninsula site. This shows a temporal decline in meteoric water in the upper ocean, contrary to expectations based on increasing precipitation and accelerating deglaciation. This is driven by the increasing occurrence of deeper winter mixed layers and has potential implications for concentrations of trace metals supplied to the euphotic zone by glacial discharge. As the regional freshwater system evolves, the continuing isotope monitoring described here will elucidate the ongoing impacts on climate and the ecosystem.
On the Bias in Simulated ENSO SSTA Meridional Widths of CMIP3 Models
Authors: Zhang Wenjun , Jin Fei-Fei , Zhao Jing-Xia , Li Jianping
Published: September 2012

The fidelity of coupled climate models simulating El Niño–Southern Oscillation (ENSO) patterns has been widely examined. Nevertheless, a systematical narrow bias in the simulated meridional width of the sea surface temperature anomaly (SSTA) of ENSO has been largely overlooked. Utilizing the preindustrial control simulations of 11 coupled climate models from phase 3 of the Coupled Model Intercomparison Project (CMIP3), it was shown that the simulated width of the ENSO SSTA is only about two-thirds of what is observed. Through a heat budget analysis based on simulations and ocean reanalysis datasets, it is demonstrated that the SSTA outside of the equatorial strip is predominantly controlled by the anomalous meridional advection by climatological currents and heat-flux damping. The authors thus propose a simple damped-advective conceptual model to describe ENSO width. The simple model indicates that this width is primarily determined by three factors: meridional current, ENSO period, and thermal damping rate. When the meridional current is weak, it spreads the equatorial SSTA away from the equator less effectively and the ENSO width thus tends to be narrow. A short ENSO period allows less time to transport the equatorial SSTA toward the off-equatorial region, and strong damping prevents expansion of the SSTA away from the equator, both of which lead to the meridional width becoming narrow. The narrow bias of the simulated ENSO width is mainly due to a systematical bias in weak trade winds that lead to weak ocean meridional currents, and partly due to a bias toward short ENSO periods.
A Simulated Climatology of Spectrally Decomposed Atmospheric Infrared Radiation
Authors: Huang Yi
Published: September 2012

A simulation experiment is conducted to inquire into the mean climate state and likely trends in atmospheric infrared radiation spectra. Upwelling and downwelling spectra at five vertical levels from the surface to the top of the atmosphere (TOA) are rigorously calculated from a climate-model-simulated atmosphere for a 25-yr period. Tracing the longwave radiation flux vertically and spectrally renders a dissection of the greenhouse effect of the earth atmosphere and its change due to climate forcings and feedbacks. The results show that the total outgoing longwave radiation (OLR) at the TOA may be conserved due to 1) compensating temperature and opacity effects and 2) contrasting temperature changes in troposphere and stratosphere. The tightly coupled tropospheric temperature and opacity effects reduce the overall tropospheric contribution to OLR change to be comparable to the overall stratospheric contribution, which suggests that transient OLR change is constrained by the relative strengths of stratospheric and tropospheric temperature changes.

The total OLR energy, however, is redistributed across its spectrum. The earliest detectable global climate change signal lies in the CO2 absorption bands, which results from stratospheric cooling and the CO2 opacity effect. This signal can be detected much sooner than surface temperature change and is little affected by achievable instrument accuracy.

In contrast, both tropospheric temperature and opacity effects increase downwelling longwave radiation (DLR), which makes DLR a verifiable aspect of global warming. The time it takes to detect surface DLR change roughly equals that of surface temperature change. Measuring downwelling radiances at strong water vapor lines at the tropopause can particularly help monitor stratospheric water vapor.