bluuebunny/crossref_metadata_2025 huggingface dataset:
Atrial Septal Defect Occluder Device Huge Thrombus in Patient with Low Ejection Fraction
Authors: Yuce Murat , Davutoglu Vedat , Sari Ibrahim , Ozer Orhan
Published: June 2010

(Echocardiography 2010,27:E96‐E97)
Echocardiographic Determinants of the Clinical Condition in Patients with a Systemic Right Ventricle
Authors: Winter Michiel M. , Bouma Berto J. , Hardziyenka Maxim , De Bruin‐Bon Rianne H.A.C.M. , Tan Hanno L. , Konings Thelma C. , Van Dijk Arie P.J. , Mulder Barbara J.M.
Published: June 2010

Background: Ventricular systolic and diastolic function, as measured by echocardiography, are diminished in patients with a systemic right ventricle (RV). As the clinical implications of these finding remained unknown, we aimed to identify echocardiographic parameters of systolic and diastolic ventricular function that are independent determinants of the clinical condition in these patients. Methods: Forty‐six adult patients (61% male; mean age 33 [range 18–69] years) with a systemic RV underwent echocardiography to assess qualitative and quantitative systolic and diastolic function of the systemic RV and the subpulmonary left ventricle (LV). Uni‐ and multivariate linear regression analyses were performed to identify independent echocardiographic determinants for NYHA class, maximal exercise capacity (V’O2peak) and NT‐proBNP levels. Results: We found qualitative assessment of RV and LV function to be significantly associated with NYHA class (RV: β= 0.26; P = 0.05 and LV: β= 0.82; P < 0.01), V’O2peak (RV: β=−10.4; P < 0.05 and LV: β=−18.4; P < 0.05) and NT‐proBNP levels (RV: β= 0.58; P < 0.01 and LV: β= 1.40; P < 0.001). Tricuspid annulus plane systolic excursion (TAPSE) was significantly associated with NYHA class (β=−0.92; P = 0.001), V’O2peak (β= 18.5; P = 0.05), and serum NT‐proBNP levels (β=−1.00; P < 0.05). Associations between quantitative parameters of systolic subpulmonary LV function and clinical parameters were less distinct. We found no associations between RV and LV diastolic function and clinical parameters. Conclusions: Qualitative function of the systemic RV and the subpulmonary LV, and TAPSE, are determinants of clinical condition in patients with a systemic RV. These patients’ clinical condition could not be determined by echocardiographically measured diastolic RV function, and systolic and diastolic LV function. (Echocardiography 2010;27:1247‐1255)
A Novel Two‐Dimensional Echocardiographic Finding in Cardiac Amyloidosis
Authors: Belkin Robert N. , Kupersmith Andrew C. , Khalique Omar , Aronow Wilbert S. , Chilappa Kiran , Palaniswamy Chandrasekar , Rosenblum Warren D. , Gass Alan , Ahmed Tauseef , Katta Umadevi S.
Published: June 2010

Background: A number of echocardiographic findings characteristic of cardiac amyloidosis (CA) have been described, each with limitations. Methods: A distinctive wall motion pattern of preserved myocardial thickening at left ventricular apex with hypokinesis in basal and midsegments was observed in two patients with biopsy proven CA. Following this observation, endomyocaradial biopsy files beginning in 2007 were reviewed. Seven consecutive patients with documented CA were identified. Two‐dimensional (2D) echocardiograms for each were reviewed in consensus by two experienced echocardiographers. Clinical and electrocardiographic data were obtained from chart review. Results: All patients were men with class II–IV heart failure. Six had light chain CA, 1 senile CA. Six patients had coronary angiography. One had a 60% left anterior descending coronary artery stenosis. Five had nonobstructive disease. Echocardiograms for all seven patients demonstrated the distinctive pattern of preserved myocardial thickening at apex with hypokinesis in basal and midsegments. Reduced ejection fraction was present in six and increased wall thickness and myocardial echogenicity in seven. Other echo signs of amyloid were variably present. Three had low voltage on electrocardiogram. Conclusion: A distinctive 2D echocardiographic pattern of preserved segmental wall motion at left ventricular apex with hypokinesis in basal to midsegments was consistently identified in seven consecutive patients with endomyocardial biopsy‐proven CA. (Echocardiography 2010;27:1171‐1176)
Elastofibromatous change of the oral mucosa: case report and literature review
Authors: Nonaka Cassiano Francisco Weege , Rêgo Delane Maria , Miguel Márcia Cristina da Costa , De Souza Lélia Batista , Pinto Leão Pereira
Published: June 2010

Elastofibroma is an uncommon fibrous pseudotumor that usually occurs in the subscapular region of middle‐aged and older adults. Since its seminal description, cases of elastofibroma or elastofibroma‐like proliferations have been identified at several anatomic locations, including the foot, hand, thigh, olecranon, gastrointestinal tract, trachea, dorsal spine and eye. Involvement of the oral cavity is rare, with only four cases reported to date. Herein, we report a case of elastofibromatous change in the soft palate of a 55‐year‐old man and review the literature regarding pathogenesis, clinicopathologic features, differential diagnosis and management.

Nonaka CFW, Rêgo DM, Miguel MCC, de Souza LB, Pinto LP. Elastofibromatous change of the oral mucosa: case report and literature review.
Isolation of the left subclavian artery from the pulmonary artery in a patient with CHARGE association
Authors: Bech Anneke P. , Op Den Akker Jeroen , Matthijsse Pieter R.
Published: June 2010

A male infant diagnosed with CHARGE association presented with respiratory insufficiency and a cardiac murmur. Diagnostic evaluation showed a right sided aortic arch with an isolation of the left subclavian artery arising from the pulmonary artery through a left patent arterial duct. This is a rare cardiac disorder not previously described in patients with CHARGE association, detected with a 3D computed tomography scan, which emphasizes the importance of a thorough cardiac screening in patients with CHARGE association.
Analysis of the harmonized growth pattern of fetal organs by multidimensional scaling and hierarchical clustering
Authors: Udagawa Jun , Yasuda Akira , Naito Kanta , Otani Hiroki
Published: June 2010

The development of an organ may be affected by various growth and differentiation factors released from other organs. These factors are believed to have important effects on the development of multiple organs. To detect and analyze harmonized development among multiple organs, similarities in growth patterns among fetal organs were examined using multivariate analysis. Ninety human fetuses obtained from the Kyoto Collection of Human Embryos were dissected. Harmonized development of organs was evaluated by multidimensional scaling and cluster analysis using measurements (length, width, height, and weight) of the fetal organs. Similar growth patterns were observed between the brain, including cerebrum, diencephalon, and midbrain (cerebrum‐to‐midbrain [Cer‐Mid]), and pituitary (crown‐rump length [CRL] 95–155 mm). Further, similar growth patterns were observed between the liver and Cer‐Mid and cerebellum (Cb; CRL 156–202 mm), and between Cer‐Mid and Cb (CRL 203–253 mm). Similarities in growth patterns were also observed between right and left lungs (CRL 99–235 mm) and between the aorta and heart (CRL 139–187 mm), but not between the lung and pulmonary trunk. These findings revealed synchronized development among fetal organs and suggested a functional and structural relationship among different organs in the prenatal period. These relationships include the existence of common factors in organ development, such as cross‐talk mediated by humoral factors, and the presence of an anatomical and functional relationship in the fetal circulatory system.
Organizational constraints on Ste12 cis‐elements for a pheromone response in Saccharomyces cerevisiae
Authors: Su Ting‐Cheng , Tamarkina Elena , Sadowski Ivan
Published: June 2010

Ste12 of Saccharomyces cerevisiae binds to pheromone‐response cis‐elements (PREs) to regulate several classes of genes. Genes induced by pheromones require multimerization of Ste12 for binding of at least two PREs on responsive promoters. We have systematically examined nucleotides of the consensus PRE for binding of wild‐type Ste12 to DNA in vitro, as well as the organizational requirements of PREs to produce a pheromone response in vivo. Ste12 binds as a monomer to a single PRE in vitro, and two PREs upstream of a minimal core promoter cause induction that is proportional to their relative affinity for Ste12 in vitro. Although consensus PREs are arranged in a variety of configurations in the promoters of responsive genes, we find that there are severe constraints with respect to how they can be positioned in an artificial promoter to cause induction. Two closely‐spaced PREs can induce transcription in a directly‐repeated or tail‐to‐tail orientation, although PREs separated by at least 40 nucleotides are capable of inducing transcription when oriented in a head‐to‐head or tail‐to‐tail configuration. We characterize several examples of promoters that bear multiple consensus PREs or a single PRE in combination with a PRE‐like sequence that match these requirements. A significant number of responsive genes appear to possess only a single PRE, or PREs in configurations that would not be expected to enable induction, and we suggest that, for many pheromone‐responsive genes, Ste12 must activate transcription by binding to cryptic or sub‐optimal sites on DNA, or may require interaction with additional uncharacterized DNA bound factors.
Urinary incontinence and sexual function in pre‐menopausal women
Authors: Serenko Ann , Morrison Barbara , Suresky Jane
Published: June 2010

The aim of this cross‐sectional, descriptive, correlational study was to determine the nature of the relationship between urinary incontinence and sexual function in pre‐menopausal women. Ninety one sexually active pre‐menopausal women, with urinary incontinence, between 22 and 54 years of age completed self‐assessment questionnaires in the home or in outpatient Urology or Gynecology clinics. The 12 item Prolapse/Urinary Incontinence Sexual Questionnaire (PISQ‐12) was used to measure the level of sexual function, and the International Consultation on Incontinence Questionnaire for Urinary Incontinence (ICIQ‐UI) was used to measure the severity of urinary incontinence. Total scores on the PISQ‐12 and ICIQ‐UI were analysed to determine the nature and strength of the relationship between severity of urinary incontinence and level of sexual function. A significant relationship was found between urinary incontinence and sexual function in pre‐menopausal women. Women with more severe urinary symptoms had lower levels of sexual function. Although findings were significant only a weak relationship was found between the two conditions. More research is needed to identify and explain other factors that may impact urinary incontinence and sexual function in pre‐menopausal women. In conclusion, results from the study will change clinical practice. Clinicians who understand the relationship between urinary incontinence and sexual function will be able to assess and discuss sexual concerns of the young female patients they treat.
Nurse practitioner led prostate biopsy: an audit to determine effectiveness and safety for patients
Authors: Turner Bruce , Pati Jhumur
Published: June 2010

Prostate cancer has become the most commonly diagnosed cancer amongst men and its detection rate continues to increase. The Department of Health in the UK has made great efforts to reduce the waiting time for the diagnosis and treatment of cancer patients leading to new and innovative ways being sought in order to meet these demands and maintain an efficient, effective and seamless service to the patients. This article presents an audit of a nurse practitioner led rapid‐access one‐stop prostate biopsy clinic and also discusses the complications involved. The audit has shown the service to be effective and safe and has demonstrated an improvement in waiting times for cancer patients.
The quantification of spermatozoa by real‐time quantitative PCR, spectrophotometry, and spermatophore cap size
Authors: DOYLE JACQUELINE M. , McCORMICK CORY R. , DeWOODY J. ANDREW
Published: June 2010

Many animals, such as crustaceans, insects, and salamanders, package their sperm into spermatophores, and the number of spermatozoa contained in a spermatophore is relevant to studies of sexual selection and sperm competition. We used two molecular methods, real‐time quantitative polymerase chain reaction (RT‐qPCR) and spectrophotometry, to estimate sperm numbers from spermatophores. First, we designed gene‐specific primers that produced a single amplicon in four species of ambystomatid salamanders. A standard curve generated from cloned amplicons revealed a strong positive relationship between template DNA quantity and cycle threshold, suggesting that RT‐qPCR could be used to quantify sperm in a given sample. We then extracted DNA from multiple Ambystoma maculatum spermatophores, performed RT‐qPCR on each sample, and estimated template copy numbers (i.e. sperm number) using the standard curve. Second, we used spectrophotometry to determine the number of sperm per spermatophore by measuring DNA concentration relative to the genome size. We documented a significant positive relationship between the estimates of sperm number based on RT‐qPCR and those based on spectrophotometry. When these molecular estimates were compared to spermatophore cap size, which in principle could predict the number of sperm contained in the spermatophore, we also found a significant positive relationship between sperm number and spermatophore cap size. This linear model allows estimates of sperm number strictly from cap size, an approach which could greatly simplify the estimation of sperm number in future studies. These methods may help explain variation in fertilization success where sperm competition is mediated by sperm quantity.
The eye of Vesalius
Authors: De Laey Jean J.
Published: June 2010

In the time of Vesalius, knowledge of ocular anatomy was limited. The first description of the anatomy of the eye comes from Democrites, for whom the eye was surrounded by two ‘coats’, filled with a homogenous fluid. The optic nerve was hollow and the lens was considered to be a postmortem artefact. Until the 15th century AD, medicine was influenced by the writings of Galenus and the model of the eye he proposed was still considered valid, even after Vesalius. According to the Alexandrian tradition, the lens was considered as the seat of visual perception. Although Vesalius rightly deserves the title of father of modern anatomy, his description of ocular anatomy was rudimentary and often incorrect. He described a musculus retractorius bulbi, which is found only in lower mammals, not in primates. The lens, the role of which as an optical device he recognized correctly, was placed too centrally in the eye. The optic nerve was not correctly placed and, following Galenus, Vesalius described only seven cranial nerves. The Galenian concept of ocular anatomy was to endure until the development of the microscope by Anthony van Leeuwenhoek. Modern ocular anatomy, in fact, can be dated from the works of Zinn.
Modeling and Simulation of the Failure and Stiffness Degradation of a Graphite Epoxy in a Three Point Bending Test
Authors: Irhirane E. H. , Abousaleh M. , Echaabi J. , Hattabi M. , Saouab A. , Bensalah M. O.
Published: June 2010

The use of composite materials with continuous fibers in the aeronautic and aerospace industries requires reliable and precise methods for the prediction of failure. Predicting failure stresses and failure modes in composite laminates is very difficult. The choice between failure criteria is complex, and there is a lack of experimental study to validate the result obtained partly because the biaxial tests are still difficult to perform. This work employs a mixed methodology based on a theoretical and an experimental approach to develop a procedure for the choice and the validation of the failure criterion. The comparison is concerned not only with the macroscopic failure but also with the succession of the failure, the failure mode, and the effect of the geometrical parameters of the test specimen. The most general failure criteria are tested by using two approaches of the stiffness reduction. A finite element code has been elaborated within our laboratory for postfailure treatment. The numerical simulation results are compared with the experimental ones and permit us to make a conclusion on the validity of the failure criteria used.
Stress Whitening Quantification of Thermoformed Mineral Filled Acrylics
Authors: Gunel E. M. , Basaran C.
Published: June 2010

Stress whitening problem in thermoformed alumina trihydrate (ATH) reinforced poly(methyl methacrylate) (PMMA) was studied. In situ heavy-gage thermoforming of acrylics was entirely replicated under laboratory controlled conditions at different operation parameters. Samples were monitored with optical microscope after the completion of the thermoforming operation. For stress whitening quantification, a new index was proposed from image histograms of processed optical micrographs. Results indicated that stress whitening in PMMA/ATH samples increases with level of plastic deformation at all thermoforming conditions. The influence of the forming rate and forming temperature on the degree of stress whitening was explained in terms of change in material behavior and microdeformation mechanisms around two characteristic temperatures of PMMA/ATH. Developed method for stress whitening quantification characterizes different levels of stress whitening with single numeric values. It is shown that stress whitening index and density of microdeformation features display a strong correlation. Higher density of particle cracks at low forming temperatures results in higher stress whitening levels. Increased surface irregularity and large size voids at high forming temperatures produce lower stress whitening.
Fatigue Behavior of Single Crystal Superalloy Bars Joined by Capacitor Discharge Welding
Authors: Chiozzi S. , Dattoma V. , Panella F.
Published: June 2010

This work concerns single crystal Ni-based superalloy welded through the capacitor discharge welding (CDW) process. The static and fatigue behavior of CMSX-4 type single crystal alloy has been analyzed, performing mechanical tests on square specimens in order to establish in detail the superalloy behavior at the expected service stresses. Tests have been conducted both at room and working temperatures (800°C), comparing base material and capacitor discharge welded joints. The material microstructure has been observed with optical and scanning electron microscopy in order to characterize welding parameters effects on the weld characteristics, analyzing base material and as-welded specimens; this way, the CDW process has been studied to perform butt joint with the better characteristics ad achieving sound welds. Microstructural modifications and the heat affected zones have been observed in the welded section as well as the interaction between weld material and parent metal. The research activities have been conducted in the frame of AWFORS project, financed by the European community.
Identification of Process Parameters for Friction Stir Welding Ti–6Al–4V
Authors: Edwards P. , Ramulu M.
Published: June 2010

An experimental study was conducted to identify acceptable welding parameters for friction stir welding Ti-6Al-4V butt joints, ranging from 3 mm to 12 mm in thickness. The primary parameters of interest were the spindle speed and feed rate. Welds were produced using spindle speeds of 140–320 rpm and feed rates between 40 mm/min and 125 mm/min. Joints were evaluated by macro- and micrometallurgical examination along with limited fatigue and tensile testing. The weld parameters were found to influence the microstructure, penetration, void formation, and tool wear among other things. A process window was identified for combinations of the feed rate and spindle speed capable of achieving defect free joints for a given tooling configuration and thickness. It was found that the tensile and fatigue properties of the welds produced in this study were comparable to Ti–6Al–4V base material properties.
Multi-Input Multi-Output (MIMO) Modeling and Control for Stamping
Authors: Lim Yongseob , Venugopal Ravinder , Ulsoy A. Galip
Published: June 2010

The binder force in sheet metal forming controls the material flow into the die cavity. Maintaining precise material flow characteristics is crucial for producing a high-quality stamped part. Process control can be used to adjust the binder force based on tracking of a reference punch force trajectory to improve part quality and consistency. The purpose of this paper is to present a systematic approach to the design and implementation of a suitable multi-input multi-output (MIMO) process controller. An appropriate process model structure for the purpose of controller design for the sheet metal forming process is presented and the parameter estimation for this model is accomplished using system identification methods. This paper is based on original experiments performed with a new variable blank holder force (or variable binder force) system that includes 12 hydraulic actuators to control the binder force. Experimental results from a complex-geometry part show that the MIMO process controller designed through simulation is effective.
Local Delamination Buckling of a Laminated Beam due to Three-Point Bending
Authors: Toya M. , Fukagawa K. , Aritomi M. , Oda M. , Miyauchi T.
Published: June 2010

Asymmetric three-point bending of a layered beam containing an interior interface crack is analyzed on the basis of the classical beam theory. Axial compressive and tensile forces are induced by bending in the parts of the beam above and below the delamination, and they are determined by modeling the cracked part as two lapped beams jointed together at the corners of both beams. When the magnitude of the applied load is small, the beam deflects, retaining the mutual contact of whole crack faces, but as the applied load reaches a critical value, local delamination buckling of the compressed part occurs. The relation between the magnitude of the applied load and the deflection at the point of load application is found to be nearly bilinear. The validity of this prediction is confirmed by experiments. It is also shown that once the delamination buckling occurs, the energy release rate generally becomes larger as compared with the case of a perfect contact of delaminated surfaces.
Experimental Characterization of Damage Processes in Aluminum AA2024-O
Authors: Kweon S. , Beaudoin A. J. , McDonald R. J.
Published: June 2010

Much of the damage mechanics literature has focused on void growth due to tensile hydrostatic stress. To clarify the effect of combined shear stress and hydrostatic stress on the development of damage, specimens of various geometries were employed in an experimental program to cover a wide range of triaxiality and shear stress. Digital image correlation (DIC) is utilized to measure the fracture strain of the 2D specimens. Experiments are paired with simulations utilizing J2 plasticity theory to complement the experiments and relate the fracture strain with combined hydrostatic and shear stresses. The results display accelerated damage for cases dominated by shear at low triaxiality. Crystal plasticity simulations were carried out using boundary conditions based on the DIC displacement field. These simulations indicate that tensile hydrostatic stress develops due to grain-to-grain interaction.
Experimental Testing of a Thermoelectric-Based Hydronic Cooling and Heating Device With Transient Charging of Sensible Thermal Energy Storage Water Tank
Authors: Kazmierczak Michael J. , Krishnamoorthy Sreenidhi , Gupta Abhishek
Published: June 2010

Experiments were performed to charge either cold or hot water thermal energy storage tanks using a heat exchanger equipped with multiple thermoelectric (TE) modules. The primary objective was to design a simple, but effective, modular Peltier heat pump system component to provide chilled or hot water for domestic use at the appliance level, and when arranged in multiple unit combinations, a system that can potentially satisfy small home cooling and heating requirements. Moreover, when the TEs are directly energized using solar photovoltaic (PV) panels, the system provides a renewable, pollution-free, and off-the-grid solution to supplement home energy needs. The present work focuses on the design and testing of a thermoelectric heat exchanger component that consists of two water channels machined from two aluminum plates with an array of three, five, or eight thermoelectric modules placed in between to transiently cool and/or heat the water in the thermal energy storage tank. The water passing over either the cold or hot side of the TE modules is recirculated to charge the cold or hot thermal storage tank, respectively. The temperatures in the prototype Peltier heat exchanger test component and thermal energy water storage tank were measured during both cold and hot tank charging operations. The thermal efficiencies of the TE heat pump cooling/heating system are reported. The effects of the TE power input, number of TE units, rate of fluid flow, and heat sink/source temperature are studied.
Computational Heat Transfer Analysis of the Effect of Skirts on the Performance of Third-World Cookstoves
Authors: Wohlgemuth Alex , Mazumder Sandip , Andreatta Dale
Published: June 2010

In many developing countries, natural gas, wood, or biomass fired cookstoves find prolific usage. Skirts, placed around the cookpot, have been proposed as a means to improve the thermal efficiency. However, use of skirts has shown conflicting results, and the role of skirts is poorly understood. In this study, a computational heat transfer analysis of a generic third-world cookstove is conducted with the goal to understand the effect of various skirt-related parameters on the overall heat transfer characteristics and thermal efficiency. A computational fluid dynamics model, including turbulence and heat transfer by all three modes, was created. The model was first validated against the experimental data, also collected as part of this study. Unknown parameters in the model were calibrated to better match the experimental observations. Subsequently, the model was explored to study the effects of several skirt-related parameters. These include the vertical position of the skirt, the width of the gap between the skirt and the cookpot, and the thermal conductivity of the skirt (insulating versus conducting material). The computational predictions suggest that the skirt must either be made out of an insulating material or insulated on the outer surface by a backing insulating layer for it to provide maximum benefits. It was also found that it must be placed at an optimum distance away from the cookpot and aligned with the mouth of the cookstove chimney for maximum thermal efficiency. An optimum set of conditions obtained through this computational analysis resulted in an increase in the thermal efficiency from 20.7% to 28.7%.
Experimental Investigation on a Rotary Regenerator Operating at Low Temperatures
Authors: Rabah A. A. , Fekete A. , Kabelac S.
Published: June 2010

This work investigated the operation conditions of a rotary regenerator operating at low regeneration temperatures, which is widely used in solar desiccant air conditioning systems. A rigorous experimental rig that facilitates the measurement of axial, radial, and angular airflow temperature distribution is used. The measurements covered balanced flow at a wide range of rotational speeds (0–24 rpm), regeneration temperatures (40–70°C), and airflow rates (160–530 kg/h). The influences of those parameters on the rotary regenerator effectiveness are presented. The results revealed that the critical effectiveness occurs at 5 rpm (equivalent to 4≤Cr∗≤13). This is lower than that for rotary regenerators operating at high regeneration temperatures and airflow rates. The results also concluded that the Kays and London correlation is sufficient for rotary regenerators operating at low regeneration temperatures. It predicted the experimental data with an average absolute percent deviation of 6.34.
Uncertainty Propagation in Abstracted Systems via the Liouville Equation
Authors: Mellodge Patricia , Kachroo Pushkin
Published: June 2010

This technical brief shows that given a system and its abstraction, the evolution of uncertain initial conditions in the original system is, in some sense, matched by the evolution of the uncertainty in the abstracted system. In other words, it is shown that the concept of Φ-related vector fields extends to the case of stochastic initial conditions where the probability density function (pdf) for the initial conditions is known. In the deterministic case, the Φ mapping commutes with the system dynamics. In this paper, we show that in the case of stochastic initial conditions, the induced mapping Φpdf commutes with the evolution of the pdf according to the Liouville equation.
Modeling and Analysis
of Flow, Thermal, and Energy Fields Within Stacks of Thermoacoustic Engines Filled With Porous
Media: A Conjugate Problem
Authors: Tasnim Syeda
Humaira , Fraser Roydon
Andrew
Published: June 2010

In this paper, an analytical study has been conducted on the flow and energy transfer of an unsteady compressible oscillating flow through channels filled with porous media representing stacks in thermoacoustic engines and refrigerators. The flow in the porous material is described by the Darcy momentum equation. The thickness of the channel wall is considered to be nonzero, and the entire problem is treated as a conjugate heat transfer problem, i.e., by considering conduction heat transfer inside the channel walls. Analytical expressions for the oscillating temperature, complex Nusselt number, and energy flux density are obtained after linearizing and solving the governing differential equations with long wave, short stack, and small amplitude oscillation approximations. To verify the present study, the energy flux density expression derived in this paper is compared with the expression available in the existing thermoacoustic literature. The two expressions match quantitatively for the limiting case of infinitely large pores. For infinitely large pore limits, the Nusselt number (nondimensional heat transfer between the porous media and the channel wall) obtained in the present study also agrees quantitatively with the nonporous medium expression reported in the literature. The present study indicates that refrigeration performance comparable to that of a traditional plastic parallel plate stack is achievable using reticulated vitreous carbon foam (ϕ=0.95, Lck=2.11) as a porous medium, which is also supported by other researchers. The system of equations developed in the present study is a helpful tool for thermal engineers and physicists to design porous stacks for thermoacoustic devices.
A Numerical and Experimental Investigation on the Fatigue Behavior of a Steel Nitrided Crankshaft for High Power IC Engines
Authors: Baragetti Sergio , Cavalleri Stefano , Terranova Angelo
Published: June 2010

Nitriding is usually applied to increase the surface properties of mechanical components and can also enhance the fatigue resistance. The aim of this paper is to investigate, by means of numerical models and experimental tests, the effects of residual stresses induced by nitriding on the fatigue behavior of a marine diesel engine crankshaft. The residual stress gradient induced by the thermochemical treatment was taken into account by means of finite element models. Experimental tests were carried out with an axial testing machine in order to validate the numerical models and assess the crankshaft mechanical parameters such as the yield strength and the fatigue limit. An experimental innovative method applied to evaluate the crankshaft residual stresses by means of strain measurements under bending was also developed. This methodology proved to be useful to determine the magnitude of the residual stresses induced by the thermal treatment into the crankshaft, and it could be applied for the evaluation of the residual stress field in several cases.
Direct Fabrication of Hierarchical Microstructures on Metals by Means of Direct Laser Interference Patterning
Authors: Bieda Matthias , Beyer Eckhard , Lasagni Andrés F.
Published: June 2010

We have studied the fabrication of hierarchical periodic microstructures on metals by means of direct laser interference patterning. A nanosecond pulsed Nd:YAG laser at 355 nm wavelength was used to produce the microstructures with grating periods ranging from 1 μm to 10 μm on stainless steel, titanium, and aluminum. The results indicate that the geometrical characteristics of the interference patterns as well as the thermal properties of the substrates determine the quality of the fabricated structures. In particular, the best structures were obtained when the material at the interference minima position remained in the solid state and the temperature at the interference maxima is below the vaporization temperature. Thermal simulations by finite element method were carried out modeling photothermal interactions of the interference pattern with the metallic substrates to evaluate laser induced thermal effects, such as temperature distribution and temperature gradients and, thus, enabling us to explain the obtained results.
Epoxy Adhesives Modified With Nano- and Microparticles for In Situ Timber Bonding: Effect of Environment on Mechanical Properties and Moisture Uptake
Authors: Ahmad Z. , Ansell M. P. , Smedley D.
Published: June 2010

The environmental stability of three room temperature cure epoxy adhesives was evaluated following exposure to temperatures of 20°C, 30°C, and 50°C at 95%RH, to 50°C in air and soaked in water for up to 90 days. The adhesives contained nano- and microparticles and were especially formulated for bonded-in timber connections, and the properties of bulk adhesives and adhesively bonded block shear specimens were evaluated. After 90 days of aging the results demonstrate critical temperature effects controlled by the glass transition temperature. The apparent free volume for all the adhesives remains constant as moisture is absorbed but plasticization takes place at high temperature and relative humidity, evidenced by the increased elongation and yield observed by strain values and scanning electron microscope. Exposure at 50°C in air causes the adhesives to postcure enhancing strength but high humidity causes degradation. Nanofiller additions enhance environmental stability but the addition of microparticles provides better moisture resistance.
A New Mixed Finite Element–Differential Quadrature Formulation for Forced Vibration of Beams Carrying Moving Loads
Authors: Jafari A. A. , Eftekhari S. A.
Published: June 2010

In this paper, a new version of mixed finite element–differential quadrature formulation is presented for solving time-dependent problems. The governing partial differential equation of motion of the structure is first reduced to a set of ordinary differential equations (ODEs) in time using the finite element method. The resulting system of ODEs is then satisfied at any discrete time point apart and changed to a set of algebraic equations by the application of differential quadrature method (DQM) for time derivative discretization. The resulting set of algebraic equations can be solved by either direct methods (such as the Gaussian elimination method) or iterative methods (such as the Gauss–Seidel method). The mixed formulation enjoys the strong geometry flexibility of the finite element method and the high accuracy, low computational efforts, and efficiency of the DQM. The application of the formulation is then shown by solving some moving load class of problems (i.e., moving force, moving mass, and moving oscillator problems). The stability property and computational efficiency of the scheme are also discussed in detail. Numerical results show that the proposed mixed methodology can be used as an efficient tool for handling the time-dependent problems.
Time-resolved Fourier transform infrared spectroscopy of the gas phase during atomic layer deposition
Authors: Sperling Brent A. , Kimes William A. , Maslar James E. , Chu Pamela M.
Published: June 2010

In this work, a Fourier transform infrared spectroscopy-based method is developed to measure the gas-phase dynamics occurring during atomic layer deposition. This new technique is demonstrated during the deposition of hafnium oxide using tetrakis(ethylmethylamido)hafnium and water vapor. The repeatability of the deposition process is utilized to signal average across multiple cycles. This approach required synchronizing the precursor injection pulses with the moving mirror of the spectrometer. The system as implemented in this work achieves spectra with a time resolution of ≈150 ms, but better resolution can be easily obtained. Using this technique, the authors are able to optically measure transients in the molecular number densities of the precursors and product that are the effects of mass transport and surface reactions.
Time to Tap Africa's Livestock Genomes
Authors: Hanotte Olivier , Dessie Tadelle , Kemp Steve
Published: June 2010

We need to better understand and exploit the genetic diversity of Africa's indigenous livestock breeds—before they fade away.
Comment on “30,000-Year-Old Wild Flax Fibers”
Authors: Bergfjord C. , Karg S. , Rast-Eicher A. , Nosch M.-L. , Mannering U. , Allaby R. G. , Murphy B. M. , Holst B.
Published: June 2010

Kvavadze
et al
. (Brevia, 11 September 2009, p. 1359) identified fiber samples as 30,000-year-old flax based on a comparison with modern flax fibers analyzed by compound microscope and on the presence of dislocations/nodes in the fibers. We argue that this evidence is not sufficient to identify the fibers as flax.
Response to Comment on “30,000-Year-Old Wild Flax Fibers”
Authors: Kvavadze Eliso , Bar-Yosef Ofer , Belfer-Cohen Anna , Boaretto Elisabetta , Jakeli Nino , Matskevich Zinovi , Meshveliani Tengiz
Published: June 2010

Bergfjord
et al
. express doubts regarding our identification of flax fibers on the basis of the morphology of their internal layers. The authors use microphotographs and descriptions of the outer layers of fibers as arguments for their claims. Morphology and structure of the outer and inner parts of fibers are radically different, however, rendering their reservations misplaced.
Reversible Microbial Colonization of Germ-Free Mice Reveals the Dynamics of IgA Immune Responses
Authors: Hapfelmeier Siegfried , Lawson Melissa A. E. , Slack Emma , Kirundi Jorum K. , Stoel Maaike , Heikenwalder Mathias , Cahenzli Julia , Velykoredko Yuliya , Balmer Maria L. , Endt Kathrin , Geuking Markus B. , Curtiss Roy , McCoy Kathy D. , Macpherson Andrew J.
Published: June 2010

A Gut Feeling

The mammalian gut is colonized by many nonpathogenic, commensal microbes. In order to prevent the body from mounting inappropriate immune responses to these microbes, plasma cells in the gut produce large amounts of immunoglobulin A (IgA) specific for commensal bacteria. Because of the difficulties of uncoupling IgA production from microbial colonization, how commensal bacteria shape the gut IgA response is not well understood.

Hapfelmeier
et al.

(p.
1705
; see the Perspective by

Cerutti

) have now devised a way to get around this problem by developing a reversible system of gut bacterial colonization in mice. Commensal-specific IgA responses were able to persist for long periods of time in the absence of microbial colonization and required the presence of high microbial loads in the gut for their induction. IgA responses upon bacterial reexposure did not resemble the synergistic prime-boost effect seen in classical immunological memory responses but rather exhibited an additive effect that matched the current bacterial content present in the gut. The body thus constantly adapts the commensal-specific immune response to the microbial species present in the gut, which contrasts with the systemic immune response, which persists in the absence of pathogenic microbes.
A Generalization of Hamilton’s Rule for the Evolution of Microbial Cooperation
Authors: smith jeff , Van Dyken J. David , Zee Peter C.
Published: June 2010

Breaking Hamilton's Rule

Hamilton's rule states that the evolution of cooperation is correlated with the kin relationship between the actor and the recipient and the degree of the benefit. However, this approximation relies on several steps of simplification that are often violated in natural systems.

Smith
et al.

(p.
1700
) derived a non-additive model for the evolution of cooperation by kin selection that could be applied to all domains of life—not just animals. Experimental data examining the bacteria
Myxococcus xanthus
showed that nonlinear interactions among cells make bacterial cooperation surprisingly resistant to cheating.
Paths Out of Illness via Faith
Miracle Cures
Saints, Pilgrimage, and the Healing Powers of Belief

by Robert A. Scott

University of California Press, Berkeley, 2010. 265 pp. $24.95, £16.95. ISBN 9780520262751.
Authors: Sternberg Esther M.
Published: June 2010

Through accounts of cures at medieval, early modern, and contemporary shrines, Scott explores the roles belief, hope, and the emotions play in healing.
Looking Beyond the Spill, Obama Highlights Long-Term Restoration
Authors: Stokstad Erik
Published: June 2010

In a primetime speech about the oil spill, President Barack Obama last week called for long-term restoration of wetlands along the Gulf of Mexico and put the secretary of the Navy, Ray Mabus, who was governor of Mississippi from 1988 to 1992, in charge of developing a plan.
Lucy's 'Big Brother' Reveals New Facets of Her Species
Authors: Gibbons Ann
Published: June 2010

The partial skeleton of a large male of
Australopithecus afarensis
, unveiled this week, is nicknamed "Big Man" because it's larger than the famous Lucy skeleton.
Invisibility Cloaks for Visible Light Must Remain Tiny, Theorists Predict
Authors: Cho Adrian
Published: June 2010

Efforts to make an invisibility cloak for shorter-wavelength visible light will never lead to something you can hide in, one team of researchers predicts. The researchers say a cloak for visible light would be so small it could hide only objects almost too tiny to be seen.
Another Quarry Sighted in the Great Mantle Plume Hunt?
Authors: Kerr Richard A.
Published: June 2010

Every report that someone has caught sight of a plume in seismic images of Earth's mantle has been greeted by roughly equal portions of support and derision. The latest claim is faring a bit better. The appeal of the new work is that it is rooted directly in data.
Not Under My Backyard, Thank You
Authors: Kerr Richard A.
Published: June 2010

Now that drillers have figured out how to extract gas trapped in shale rock, a new and perhaps more hazardous style of drilling is coming to parts of the country unfamiliar with the ways of the oil and gas industry.
Characterization of Anti-
Salmonella enterica
Serotype Typhi Antibody Responses in Bacteremic Bangladeshi Patients by an Immunoaffinity Proteomics-Based Technology
Authors: Charles Richelle C. , Sheikh Alaullah , Krastins Bryan , Harris Jason B. , Bhuiyan M. Saruar , LaRocque Regina C. , Logvinenko Tanya , Sarracino David A. , Kudva Indira T. , Eisenstein Jana , Podolsky Michael J. , Kalsy Anuj , Brooks W. Abdullah , Ludwig Albrecht , John Manohar , Calderwood Stephen B. , Qadri Firdausi , Ryan Edward T.
Published: June 2010

Salmonella enterica
serotype Typhi is the cause of typhoid fever and a human-restricted pathogen. Currently available typhoid vaccines provide 50 to 90% protection for 2 to 5 years, and available practical diagnostic assays to identify individuals with typhoid fever lack sensitivity and/or specificity. Identifying immunogenic
S
. Typhi antigens expressed during human infection could lead to improved diagnostic assays and vaccines. Here we describe a platform
i
mmunoaffinity
p
roteomics-based
t
echnology (IPT) that involves the use of columns charged with IgG, IgM, or IgA antibody fractions recovered from humans bacteremic with
S
. Typhi to capture
S
. Typhi proteins that were subsequently identified by mass spectrometry. This screening tool identifies immunogenic proteins recognized by antibodies from infected hosts. Using this technology and the plasma of patients with
S
. Typhi bacteremia in Bangladesh, we identified 57 proteins of
S.
Typhi, including proteins known to be immunogenic (PagC, HlyE, OmpA, and GroEL) and a number of proteins present in the human-restricted serotypes
S
. Typhi and
S
. Paratyphi A but rarely found in broader-host-range
Salmonella
spp. (HlyE, CdtB, PltA, and STY1364). We categorized identified proteins into a number of major groupings, including those involved in energy metabolism, protein synthesis, iron homeostasis, and biosynthetic and metabolic functions and those predicted to localize to the outer membrane. We assessed systemic and mucosal anti-HlyE responses in
S
. Typhi-infected patients and detected anti-HlyE responses at the time of clinical presentation in patients but not in controls. These findings could assist in the development of improved diagnostic assays.
Evaluation of the Integrated Database Network System (IDNS) SmartGene Software for Analysis of 16S rRNA Gene Sequences for Identification of
Nocardia
Species
Authors: Conville Patricia S. , Murray Patrick R. , Zelazny Adrian M.
Published: June 2010

16S rRNA gene sequences of 102
Nocardia
isolates were analyzed using the Integrated Database Network System (IDNS) SmartGene centroid database. A total of 76% of the isolates were correctly identified. Discordant identifications were due to inadequate centroid length (3 species), inaccurate or insufficient entries in the public databases (5 species), and heterogeneous sequences among members of a species (1 species).
Evaluation of a Commercial SD Dengue Virus NS1 Antigen Capture Enzyme-Linked Immunosorbent Assay Kit for Early Diagnosis of Dengue Virus Infection
Authors: Wang Seok Mui , Sekaran Shamala Devi
Published: June 2010

Early definitive diagnosis of dengue virus infection may help in the timely management of dengue virus infection. We evaluated the Standard Diagnostics (SD, South Korea) dengue virus nonstructural protein NS1 antigen enzyme-linked immunosorbent assay (SD dengue NS1 Ag ELISA) for the detection of dengue virus NS1 antigen in patients' sera, using a total of 399 serum samples in a comparison with real-time reverse transcription (RT)-PCR, an in-house IgM capture (MAC)-ELISA, and a hemagglutination inhibition (HI) assay. Of the 320 dengue sera, 205 (64%) tested positive for NS1 antigen compared to 300 (93.75%) by either MAC-ELISA or RT-PCR, 161 (50.31%) by RT-PCR, and 226 (70.36%) by MAC-ELISA only. The assay was able to detect NS1 antigen in convalescent-phase sera until day 14 of infection. The NS1 detection rate is inversely proportional while the IgM detection rate is directly proportional to the presence of IgG antibodies. The overall sensitivity and specificity of the SD dengue NS1 Ag ELISA in the detection of “confirmed dengue virus” sera are 76.76% and 98.31%, respectively. This suggests that the SD kit is highly specific and sensitive for the detection of NS1 antigen. However, caution is needed when the kit is used as a single assay, as detection in samples that contained the virus was only about 81.97%. Combining this assay with an IgM and/or IgG assay will increase the sensitivity of detection, especially in areas with a higher prevalence of secondary dengue virus infections.