bluuebunny/crossref_metadata_2025 huggingface dataset:
Association Between Preoperative Erectile Dysfunction and Prostate Cancer Features—An Analysis from the Duke Prostate Center Database
Authors: Kimura Masaki , Bañez Lionel L. , Gerber Leah , Qi Jim , Tsivian Matvey , Freedland Stephen J. , Satoh Takefumi , Polascik Thomas J. , Baba Shiro , Moul Judd W.
Published: December 2011

Introduction

Erectile dysfunction (ED) is related to several co-morbidities including obesity, metabolic syndrome, cigarette smoking, and low testosterone, all of which have been reported to be associated with adverse prostate cancer features.

Aim

To examine whether preoperative ED has a relationship with adverse prostate cancer features in patients who underwent radical prostatectomy (RP).

Methods

We analyzed data from our institution on 676 patients who underwent RP between 2001 and 2010. Crude and adjusted logistic regression models were used to investigate the association between preoperative ED and several pathological parameters. The log-rank test and multivariate proportional hazards model were conducted to determine the association of preoperative ED with biochemical recurrence (BCR).

Main Outcome Measures

The Expanded Prostate Cancer Index Composite (EPIC) instrument was used to evaluate preoperative erectile function (EF). Preoperative normal EF was defined as EPIC-SF ≥ 60 points while ED was defined as preoperative EPIC-SF lower than 60 points.

Results

Preoperatively, a total of 343 (50.7%) men had normal EF and 333 (49.3%) men had ED. After adjusting for covariates, preoperative ED was identified a risk factor for positive extracapsular extension (OR 1.57; P = 0.029) and high percentage of tumor involvement (OR 1.56; P = 0.047). In a Kaplan-Meier curve, a trend was identified that patients with ED had higher incidence of BCR than men with normal EF (P = 0.091). Moreover, using a multivariate Cox model, higher preoperative EF was negatively associated with BCR (HR 0.99; P = 0.014).

Conclusions

These results suggest that the likelihood for adverse pathological outcomes as well as BCR following prostatectomy is higher among men with preoperative ED, though these results require validation in larger datasets. The present study indicates that preoperative ED might be a surrogate for adverse prostate cancer outcomes following RP.
Are Urology Residents Ready to Treat Premature Ejaculation After Their Training?
Authors: Luján Saturnino , García-Fadrique Gonzalo , Morales Gonzalo , Morera Jose , Broseta Enrique , Jiménez-Cruz J. Fernando
Published: December 2011

Introduction

The management of premature ejaculation (PE) among urology residents (URs) in the era of standard definition and new treatments is unknown.

Aim

To determine how future urologists currently address PE and to review their adherence to guidelines.

Methods

A specifically designed survey on the preferred approaches to the treatment of PE was given to residents during the Eighth European Urology Education Programme. The results were tabled, and descriptive statistics were used to analyze differences in practice patterns.

Main Outcomes Measures

The responses are compared with clinical guidelines and recommendations.

Results

A total of 360 URs attended the recommendation course, and 140 answered the survey (response rate: 38.8%). Seventeen (12.1%) of the respondents considered PE to be a very common sexual dysfunction, 62 (44.3%) considered PE to be frequent, 33 (23.6%) considered this condition uncommon, and 28 (20%) did not consider PE to be a dysfunction. Regarding incidents, 67 residents (47.9%) treated one patient per week. To assess PE, 132 (94.3%) used sexual history, 37 (26.4%) used physical examination, 38 (27.1%) used questionnaires, and 4 (2.9%) used laboratory testing. The preferred initial management strategy for PE was psychological/behavioral therapy for 65 (46.4%) residents. Topical anesthetic, andrological referral, and prescription of selective serotonin reuptake inhibitors (SSRIs) on demand were favored by 34 (24.3%), 19 (13.6%), and 8 (12.9%) of the respondents, respectively. Other options were psychiatric referral, which was preferred by two (1.4%) respondents, and prescription of daily SSRIs, which was preferred by two (1.4%) respondents. The preferred secondary treatment for patients who did not improve initially was prescription of SSRIs for on demand, which was 46 (32.9%) respondents. In cases where patients had concomitant erectile dysfunction (ED), 16 (11.4%) URs treated only the ED and 60 (42.9%) treated both conditions.

Conclusions

The majority of URs follow the established guidelines for diagnosis of PE, but not for treatment. The URs have an insufficient medical education in sexual medicine.
Female Sexual Function and Gestational Diabetes
Authors: Ribeiro Meireluci Costa , Nakamura Mary Uchiyama , de Tubino Scanavino Marco , Torloni Maria Regina , Mattar Rosiane
Published: December 2011

Introduction

The number of women with gestational diabetes mellitus (GDM) is growing worldwide in parallel with the obesity epidemic. The diagnosis of GDM leads to substantial modifications in the daily routine of these women, and these adjustments could potentially affect their sexual function. There are no previous studies on the sexual function of patients with GDM.

Aim

The aim of this study was to investigate the sexual function of patients with GDM in comparison with healthy pregnant women at the same gestational age.

Methods

Brazilian women in the third trimester of pregnancy with and without GDM were invited to participate in this cross-sectional study while waiting for their antenatal care visits at a single public tertiary teaching institution between March and December 2010. The Brazilian version of the Female Sexual Function Index (FSFI) questionnaire was used to assess sexual function.

Main Outcome Measures

Desire, arousal, lubrication, orgasm, sexual satisfaction, and pain during and after coitus in the last 4 weeks, measured according to a standardized and validated questionnaire.

Results

A total of 87 participants were enrolled (43 healthy women and 44 with GDM). There were no significant differences in the sociodemographic characteristics of both groups. The total FSFI scores of GDM patients was 21.0 ± 9.59 compared with 22.3 ± 9.17 for healthy women (P = 0.523). Difficulty in desire was the most common sexual dysfunction symptom in both groups, being reported by 42% and 50% of GDM and healthy women, respectively (P = 0.585).

Conclusion

The sexual function of Brazilian patients with GDM does not differ significantly from that of healthy pregnant women at the same gestational age.
Choosing the Best Candidates for Penile Rehabilitation After Bilateral Nerve-Sparing Radical Prostatectomy
Authors: Briganti Alberto , Di Trapani Ettore , Abdollah Firas , Gallina Andrea , Suardi Nazareno , Capitanio Umberto , Tutolo Manuela , Passoni Niccolò , Salonia Andrea , DiGirolamo Valerio , Colombo Renzo , Guazzoni Giorgio , Rigatti Patrizio , Montorsi Francesco
Published: December 2011

Introduction

Controversy exists regarding the ideal candidates for penile rehabilitation after bilateral nerve-sparing radical prostatectomy (BNSRP).

Aim

To test the effect of penile rehabilitation according to preoperative patient characteristics.

Methods

We included 435 consecutive patients treated with BNSRP between 2004 and 2008. Preoperative age, International Index of Erectile Function (IIEF) and Charlson Comorbidity Index (CCI) were used to subdivide patients into three groups according to foreseen risk of erectile dysfunction (ED) after surgery: low (age ≤65, IIEF-erectile function (EF) ≥26, CCI ≤1; N = 184), intermediate (age 66–69 or IIEF-EF 11–25, CCI ≤1; N = 115), and high (age ≥70 or IIEF-EF ≤10 or CCI ≥2; N = 136). The Kaplan–Meier method was used to test the difference in EF recovery rates among patients left untreated after surgery (N = 193), those receiving on-demand phosphodiesterase type 5 inhibitors (PDE5-I; N = 147), and those treated with chronic use of PDE5-I (taken every day or every other day for 3–6 months; N = 95). The same analyses were repeated within each risk category.

Main Outcome Measure

Erectile function (EF) was evaluated using the International Index of Erectile Function (IIEF). Recovery of EF after BNSRP was defined as an IIEF-EF domain score ≥22.

Results

No difference in terms of EF recovery was found between patients receiving on-demand vs. daily PDE5-I (P = 0.09) in the overall population. Similarly, comparable efficacy of the two treatment schedules (on-demand vs. chronic) was demonstrated in patients with low and high risk of ED (all P ≥ 0.8). Conversely, daily therapy with PDE5-I showed significantly higher efficacy for the EF recovery rate compared with the on-demand PDE5-I administration schedule in patients with intermediate risk of ED (3-year EF recovery: 74% vs. 52%, respectively; P = 0.02).

Conclusions

The ideal candidates for penile rehabilitation after surgery are patients at intermediate risk of ED.
Effects of Abdominoplasty on Female Sexuality: A Pilot Study
Authors: de Brito Maria José Azevedo , Nahas Fábio Xerfan , Bussolaro Rodolpho Alberto , Shinmyo Lia Mayumi , Barbosa Marcus Vinicius Jardini , Ferreira Lydia Masako
Published: December 2011

Introduction

Changes in the pubic region resulting from abdominoplasty may have a psychosexual impact. Thus, it is important to study the influence of physical changes on the sexuality of patients after abdominoplasty.

Aim

To evaluate the effects of the elevation of the mons pubis and consequent exposure of the clitoris in the vulvar commissure on the sexual functioning and sexual satisfaction of women who underwent abdominoplasty.

Methods

Data were presented as mean ± standard deviation. Nineteen women with a mean age of 35 ± 7 years, mean body mass index of 23 ± 2 kg/m2 and who expressed a desire to undergo abdominoplasty were selected from consecutive patients attending the abdominal plastic surgery outpatient unit of a university hospital.

Main Outcome Measures

Physical change (measured by the distance between the xiphoid process and vulvar commissure [xipho-vc]), sexual functioning, and sexual satisfaction (assessed with the Sexuality Assessment Scale), and body image (measured using the Body Shape Questionnaire [BSQ]) were evaluated preoperatively and 6 months after abdominoplasty.

Results

There was a significant reduction (P = 0.0004; z = −3.53) in the xipho-vc distance 6 months after abdominoplasty compared with baseline (mean difference 3.63 ± 2.79 cm), corresponding to an elevation of the mons pubis and consequent exposure of the clitoris. All patients reported a significant improvement in sexual functioning and sexual satisfaction 6 months after abdominoplasty when compared with baseline (P = 0.0001; z = −3.83). BSQ scores indicated an improvement in the patients’ concerns about body shape (P = 0.0003; z = −3.58).

Conclusion

Our results suggest that physical change and the new position of the clitoris may have a positive impact on sexuality.
Erectile Dysfunction is the Main Determinant of Psychological Distress in Men with Spinal Cord Injury
Authors: Barbonetti Arcangelo , Cavallo Francesca , Felzani Giorgio , Francavilla Sandro , Francavilla Felice
Published: December 2011

Introduction

The weight of erectile dysfunction (ED) among the various determinants of psychological distress in men with spinal cord injury (SCI) remains to be clarified.

Aim

The aim of this article was to evaluate psychological distress features in SCI men with or without ED.

Methods

Forty consecutive patients with neurologically stable SCI were included in the study. Functional independence (FI) was assessed by Barthel Index (BI), which was divided into global score (questions 1–10) and bowel/bladder subscore (questions 5 and 6). Erectile function was evaluated with Sexual Health Inventory for Men (SHIM).

Main Outcome Measures

Psychological distress was assessed with the Symptom Checklist-90-revised (SCL-90-R), scoring nine primary dimensions and their combination as Global Severity Index, a global index of psychological distress.

Results

All SCL-90-R scores and the percentage of patients with scores >75th percentile of the entire study population were significantly higher in the group with ED (N = 21) than without ED (N = 19). Most of SCL-90-R subscales were inversely correlated with SHIM score. ED was exhibited by a high proportion (84%) of men with thoracolumbar lesions but by no patients with cervical lesions. Men with cervical lesions exhibited significantly lower SCL-90-R scores than those with thoracolumbar lesions, in spite of lower FI. However, the thoracolumbar group also reported a more severe bowel/bladder dysfunction. At multivariate logistic regression analysis, ED score significantly explained the variance of most of SCL-90-R dimension scores, whereas no association was revealed between global BI and any score of SCL-90-R dimensions. Bowel/bladder BI explained only to a very low extent the variance of depressive symptoms.

Conclusions

Healthcare providers should be aware of the importance of managing ED in spinal cord-injured men, as it represents a major determinant of their psychological distress, independently of the degree of FI impairment.
Leaf cutting‐patterns and general cradle formation process of thirteen Apoderinae (Coleoptera: Attelabidae) in Korea: Cradles of Attelabidae in Korea I
Authors: PARK Jinyoung , LEE Jong Eun , PARK Jong Kyun
Published: December 2011

The distinctive feature of leaf‐rolling weevils is their special care for their progeny. In many species among the family Attelabidae, the female recognizes the size and shape of the leaf of the host‐plant and does the leaf cutting by a definite method. The location of cutting line, length and shape becomes the basic information in understanding the most fundamental structure of female's recognition process and cradle formation strategy. Leaf cutting is not only the process of withering the leaf by blocking the water flow along the main vein but also the process of making reversal easy at the leaf‐blade part. The difference in forms of cutting line, leaf blade, interval or dispersion of nibble marks on the stem and pitch of leaf rolling has effects on the shape of the completed cradle. In the present paper we provide leaf‐cutting patterns and the cradle formation process for 13 species of subfamily Apoderinae. We also provide a pictorial key of the cradle for the first time in Korea.
Sixth International Congress on Shwachman‐Diamond syndrome: from patients to genes and back
Authors: Liu Johnson M. , Lipton Jeffrey M. , Mani Sridhar
Published: December 2011

At the Sixth International Congress on Shwachman‐Diamond syndrome, held at the New York Academy of Sciences on June 28–30, 2011, researchers from around the world met to discuss the latest clinical and basic science relating to this puzzling condition.
The history of the tetracyclines
Authors: Nelson Mark L. , Levy Stuart B.
Published: December 2011

The history of the tetracyclines involves the collective contributions of thousands of dedicated researchers, scientists, clinicians, and business executives over the course of more than 60 years. Discovered as natural products from actinomycetes soil bacteria, the tetracyclines were first reported in the scientific literature in 1948. They were noted for their broad spectrum antibacterial activity and were commercialized with clinical success beginning in the late 1940s to the early 1950s. The second‐generation semisynthetic analogs and more recent third‐generation compounds show the continued evolution of the tetracycline scaffold toward derivatives with increased potency as well as efficacy against tetracycline‐resistant bacteria, with improved pharmacokinetic and chemical properties. Their biologic activity against a wide spectrum of microbial pathogens and their uses in mammalian models of inflammation, neurodegeneration, and other biological systems indicate that the tetracyclines will continue to be successful therapeutics in infectious diseases and as potential therapeutics against inflammation‐based mammalian cell diseases.
Solvent Effects on the Steady State Photophysics of Estrone and 17β‐Estradiol
Authors: Chan Kara Y. , Gavaghan Bridget M. , Stoeckel Andrew W. , Irizarry Karla , Hare Patrick M.
Published: December 2011

Absorption and emission yields for estrone and 17β‐estradiol were measured in a variety of room temperature solvents. Molar extinction coefficients were found to not vary as a function of solvent, while fluorescence yields were found to be significantly affected by the polarity and hydrogen‐bond accepting ability of the solvent, with the yield for 17β‐estradiol being highest in nonpolar, hydrogen‐bond donating solvents, and lowest in the nonpolar, hydrogen‐bond accepting solvent ethyl acetate. Estrone’s emission yield was found to be a factor of ten smaller than 17β‐estradiol’s. Strong solvent and excitation wavelength dependences were found for the relative amounts of emission between estrone’s two emission bands, with increased relative emission occurring in nonpolar aprotic solvents, and under higher excitation energies. These results are interpreted with the aid of vertical excitation energies from time‐dependent density functional calculations using both explicit and implicit solvation models.
Genetic structure and local adaptation of European wheat yellow rust populations: the role of temperature‐specific adaptation
Authors: Mboup Mamadou , Bahri Bochra , Leconte Marc , De Vallavieille‐Pope Claude , Kaltz Oliver , Enjalbert Jérôme
Published: December 2011

Environmental heterogeneity influences coevolution and local adaptation in host–parasite systems. This also concerns applied issues, because the geographic range of parasites may depend on their capacity to adapt to abiotic conditions. We studied temperature‐specific adaptation in the wheat yellow/stripe rust pathogen, Puccinia striiformis f.sp. tritici (PST). Using laboratory experiments, PST isolates from northern and southern France were studied for their ability to germinate and to infect bread and durum wheat cultivars over a temperature gradient. Pathogen origin × temperature interactions for infectivity and germination rate suggest local adaptation to high‐ versus low‐temperature regimes in south and north. Competition experiments in southern and northern field sites showed a general competitive advantage of southern over northern isolates. This advantage was particularly pronounced in the southern ‘home’ site, consistent with a model integrating laboratory infectivity and field temperature variation. The stable PST population structure in France likely reflects adaptation to ecological and genetic factors: persistence of southern PST may be due to adaptation to the warmer Mediterranean climate; and persistence of northern PST can be explained by adaptation to commonly used cultivars, for which southern isolates are lacking the relevant virulence genes. Thus, understanding the role of temperature‐specific adaptations may help to improve forecast models or breeding programmes.
Noninvasive molecular methods to identify live scarab larvae: an example of sympatric pest and nonpest species in New Zealand
Authors: LEFORT M.‐C. , BOYER S. , WORNER S. P. , ARMSTRONG K.
Published: December 2011

Despite the negative impact that many scarab larvae have on agro‐ecosystems, very little attention has been paid to their taxonomy. Their often extremely similar morphological characteristics have probably contributed to this impediment, which has also meant that they are very difficult to identify in the field. Molecular methods can overcome this challenge and are particularly useful for the identification of larvae to enable management of pest species occurring sympatrically with nonpest species. However, the invasive collection of DNA samples for such molecular methods is not compatible with subsequent behavioural, developmental or fitness studies. Two noninvasive DNA sampling and DNA analysis methods suitable for the identification of larvae from closely related scarab species were developed here. Using the frass and larval exuviae as sources of DNA, field‐collected larvae of Costelytra zealandica (White) and Costelytra brunneum (Broun) (Scarabaeidae: Melolonthinae) were identified by multiplex PCR based on the difference in size of the resulting PCR products. This study also showed that small quantities of frass can be used reliably even 7 days after excretion. This stability of the DNA is of major importance in ecological studies where timeframes rarely allow daily monitoring. The approach developed here is readily transferable to the study of any holometabolous insect species for which morphological identification of larval stages is difficult.
THE EFFECTS OF BANKING RELATIONSHIP, LEGAL ORIGIN, PRIVATE EQUITY AND LEAD MANAGERS ON THE PERFORMANCE OF WEST AFRICAN IPO FIRMS
Authors: HEARN BRUCE
Published: December 2011

This paper examines the performance effects arising from initial primary offering (IPO) firms retaining their existing bank as a lead manager together with the effects of foreign and domestic lead managers, corporate insiders and private equity investors across West Africa. Using a unique and comprehensive sample of 37 locally listed IPO firm's from across West Africa, I find evidence of a considerable reduction in underpricing and costs of equity in firms listing on civil code as opposed to common law markets. Furthermore, I find evidence that firms employing their existing bank as lead manager have higher costs of equity while the employment of a foreign as opposed to domestic lead manager imparts a reduction in underpricing and cost of equity.
ACCOUNTING FOR THE SIZE OF THE INFORMAL SECTOR IN NIGERIA
Authors: SOLOMON OFFIONG HELEN
Published: December 2011

This paper uses a Real Business Cycle (RBC) model to analyse and simulate the effect of a negative oil‐price shock on the informal sector in Nigeria. Secondly, the paper shows that RBC theory can account for the size of the informal sector as produced by the Multiple Indicator Multiple Cause (MIMIC) model. The MIMIC model has been criticised for generating estimates of the informal sector without an underlying theory. This paper shows that the model's estimates of the informal sector can be supported by theory.
A Contribution for Virtual Prototyping of Mechatronic Systems Based on Real-Time Distributed High Level Architecture
Authors: Hadj-Amor H. J. , Soriano T.
Published: December 2011

Mechatronics is the integration of different sciences and techniques of mechanical engineering, automatic control, electronics, and informatics. The rapid evolution of the market competitors requires the reduction of development time of a product while increasing the quality and performance. It is, therefore, necessary to increase the efficiency of the design process. To meet this need, simulation and, especially, virtual prototyping have become a key technology. It is difficult to find simulation tools are able to analyze multidependent systems of different areas. However, an environment that allows a simulation integrating multidisciplinary mechatronic systems is necessary. This paper describes a method of design and simulation of mechatronic systems. First, we identify the behavior model and its associated 3D geometric model. The behavior model is seen as a dynamic hybrid system of two coupled hybrid automata (operative part and control part). Then, we present OpenMASK and OpenModelica simulators, the IEEE1516 standard HLA and work related to this distributed architecture for simulation. In a top-down approach, we present our method and experiments to integrate HLA functionalities in these simulators and to distribute the modeling elements of mechatronic systems. Also, we propose extensions to integrate real-time for interactive simulations. Finally, we apply our approach on a representative example of a mechatronic system.
Machining of Aircraft Titanium With Abrasive-Waterjets for Fatigue Critical Applications
Authors: Liu H.-T. , Hovanski Y. , Dahl M. E.
Published: December 2011

Laboratory tests were conducted to determine the fatigue performance of abrasive-waterjet- (AWJ-) machined aircraft titanium. Dog-bone specimens machined with AWJs were prepared and tested with and without sanding and dry-grit blasting with Al2O3 as the secondary processes. The secondary processes were applied to remove the visual appearance of AWJ-generated striations and to clean up the garnet embedment. The fatigue performance of AWJ-machined specimens was compared with baseline specimens machined with Computer Numerical Control (CNC) milling. Fatigue test results of the titanium specimens not only confirmed our previous findings in aluminum dog-bone specimens but also further enhanced the fatigue performance of the titanium. In addition, titanium is known to be difficult to cut, particularly for thick parts, however, AWJs cut the material 34% faster than stainless steel. AWJ cutting and dry-grit blasting are shown to be a preferred combination for processing aircraft titanium that is fatigue critical.
Several Factors Affecting the Electroplastic Effect During an Electrically-Assisted Forming Process
Authors: Salandro Wesley A. , Bunget Cristina J. , Mears Laine
Published: December 2011

Recent development of electrically-assisted manufacturing (EAM) processes proved the advantages of using the electric current, mainly related with the decrease in the mechanical forming load and improvement in the formability. From EAM experiments, it has been determined that a portion of the applied electrical power contributes toward these forming benefits and the rest is dissipated into heat, defined as the electroplastic effect. The objective of this work is to experimentally investigate several factors that affect the electroplastic effect and the efficiency of the applied electricity. Specifically, the effects of various levels of cold work and contact force are explored on both Grade 2 and Grade 5 Titanium alloys. Thermal and mechanical data prove that these factors notably affect the efficiency of the applied electricity during an electrically-assisted forming (EAF) process.
On Boundary Damping for an Axially Moving Tensioned Beam
Authors: Sandilo Sajad H. , van Horssen Wim T.
Published: December 2011

In this paper, an initial-boundary value problem for a linear-homogeneous axially moving tensioned beam equation is considered. One end of the beam is assumed to be simply-supported and to the other end of the beam a spring and a dashpot are attached, where the damping generated by the dashpot is assumed to be small. In this paper only boundary damping is considered. The problem can be used as a simple model to describe the vertical vibrations of a conveyor belt, for which the velocity is assumed to be constant and relatively small compared to the wave speed. A multiple time-scales perturbation method is used to construct formal asymptotic approximations of the solutions, and it is shown how different oscillation modes are damped.
Efficient Solution of Maggi’s Equations
Authors: García de Jalón Javier , Callejo Alfonso , Hidalgo Andrés F.
Published: December 2011

According to a recent paper (Laulusa and Bauchau, 2008, “Review of Classical Approaches for Constraint Enforcement in Multibody Systems,” ASME J. Comput. Nonlinear Dyn., 3(1), 011004), Maggi’s formulation is a simple and stable way to solve the dynamic equations of constrained multibody systems. Among the difficulties of Maggi’s formulation, Laulusa and Bauchau quoted the need for an appropriate choice (and change, when necessary) of independent coordinates, as well as the high cost of computing and updating the basis of the tangent null space of constraint equations. In this paper, index-1 Lagrange’s equations are first considered, including the not-so-rare case of having a singular mass matrix and redundant constraints. The existence and uniqueness of solution for acceleration vector and Lagrange multipliers vector is studied in a very simple way. Then, following Von Schwerin (Von Schwerin, Multibody System Simulation. Numerical Methods, Algorithms and Software, Springer, New York, 1999), Maggi’s formulation is described as the most efficient way (in general) to solve these index-1 equations. Next, an improved double-step method, which implements the matrix transformations of Maggi’s formulation in an efficient way, is described. Finally, two large real-life examples are presented.
Influence of Forging Process on Fatigue Properties of AISI 4140 Steel Axle Component
Authors: Perumal Venkateswaran , Palanivelu Sivakumar , Mookherjee Siba Prasad , Jindal Ajit Kumar
Published: December 2011

The present paper investigates the microstructure and mechanical properties’ aspects of AISI 4140 steel front axle beams developed by roll and hot-die forging processes. Microstructure of the processed beams exhibited tempered martensite, and nonmartensitic products, such as retained austenite and ferrite at the case and core, respectively. Fatigue testing results indicate that roll forged beams have demonstrated 37% higher fatigue lives (Weibull B50 life) compared to hot-die forged beams, despite similar quasi-static tensile properties. The improved fatigue performance of the roll forged beams over hot-die forged beams is attributed to the fine, close texture and rationalized material flow in the beams processed by the roll forging process. Finite element analysis and experimental strain measurements of subject component indicate that the stress levels due to fatigue loads are well below the static yield strength and endurance limit of AISI 4140 steel; however, the notches present in the form of flash or partition lines of the forged beams have initiated the fatigue failures of the beams.
In situ diagnostics for studying gas-surface reactions during thermal and plasma-assisted atomic layer deposition
Authors: Rai Vikrant R. , Agarwal Sumit
Published: December 2011

The authors have constructed a novel experimental setup to investigate the surface reaction mechanisms during thermal and plasma-assisted atomic layer deposition (ALD) of thin films by employing in situ surface and gas-phase diagnostic techniques. Specifically, we have used a real-time attenuated total reflection Fourier transform infrared spectroscopy setup to detect the surface adsorbates as well as gas-phase species in each half-reaction cycle during ALD. In this article, we describe the reactor construction and the in situ diagnostics with sufficient details that it can be a useful reference for researchers in the field. To illustrate the use of these in situ diagnostics, we present our results for the ALD of TiO2 from titanium tetraisopropoxide in conjunction with H2O, O3, and a O2 plasma. For O2 plasma-assisted ALD, our measurements are complimented with optical emission spectroscopy to identify the radicals and excited molecular species in the plasma, some of which are produced by the dissociation of the surface reaction products. The authors show that in O3- and O2 plasma-assisted ALD processes, the surface reaction products play an important role in determining the surface chemistry.
Black hole heat engine
Authors: Opatrný Tomáš , Richterek Lukáš
Published: December 2011

Two black holes can merge to create a bigger black hole, thus increasing the entropy of the universe. Alternatively, they can be used as two heat reservoirs from which work can be extracted. We discuss a process during which two black holes are transformed into one while the total entropy is kept as constant. The resulting black hole has a smaller mass than the total mass of the input black holes and the mass difference is converted into work. Although the process will probably not be used within the next 1011 yr for energy production, we can speculate that it might be an energy source for those who might inhabit our universe after that. We discuss the basic thermodynamics of the proposed system.
Analysis of a three phase induction motor directly from Maxwell’s equations
Authors: Bhattacharjee Shayak
Published: December 2011

The torque developed in a three phase AC squirrel cage motor is usually expressed in terms of resistances and reactances of the stator, the rotor, and the motor as a whole. We use Maxwell’s equations to find the torque in terms of geometrical parameters. This formulation allows us to estimate the torque developed by a motor without knowing the details of its circuitry.
Eighteenth century treatment of a classical mechanic problem
Authors: Stefanini Ledo
Published: December 2011

The behavior of a heavy cylinder sliding on the ground is discussed in many introductory mechanics classes. We revisit a solution that was given in the late eighteenth century and compare it with the solution that today’s textbooks usually present.
Orthonormal basis for nonparaxial focused fields in two dimensions, and its application to modeling scattering and optical manipulation of objects
Authors: Lombardo Krista , Alonso Miguel A.
Published: December 2011

A new family of rigorous solutions to the two-dimensional Helmholtz equation is discussed. These solutions form a complete orthonormal basis in terms of which any focused field can be expressed. The directionality of each element of this basis is regulated by a parameter which is related to an imaginary displacement of the focus. The forces and torques that these fields and any linear combination of them exert on a homogeneous circular scatterer can be calculated analytically, regardless of the relative position between the scatterer and the focus.
Direct visualization of terahertz electromagnetic waves in classic experimental geometries
Authors: Werley Christopher A. , Nelson Keith A. , Ryan Tait C.
Published: December 2011

We used newly developed experimental methods to collect educational video clips of electromagnetic waves propagating at the speed of light. The terahertz frequency waves were generated and detected in LiNbO3 crystals structured to reproduce classic optical geometries and experiments, such as two-slit interference and diffraction from a grating. Direct visualization of the phase fronts as the electromagnetic pulses propagate, reflect, diffract, and interfere helps develop intuition and understanding about the fundamental behavior of light and waves. We believe these videos will be a valuable addition to lectures on introductory optics and physics, because they bring contemporary research to the classroom and provide clear and direct experimental demonstrations of light and wave behavior.
Detection and location of cracks using loss of reciprocity in ultrasonic waves propagation
Authors: Scalerandi M. , Gliozzi A. S. , Bruno C. L. E.
Published: December 2011

The reciprocity theorem is a general statement valid for elastic media, and it has been applied to the solution of elastic wave equations, transducers calibration, time reversal acoustics, etc. However, localized nonlinear scatterers are expected to break reciprocity even though the effect is, in several cases, negligible. Here the dependence of the reciprocity break on the presence of a localized damage and the influence of its relative position has been experimentally investigated. It will be shown that the break of reciprocity, usually considered a disadvantage, can be exploited as an imaging tool for localized cracks detection.
Npas4 Regulates a Transcriptional Program in CA3 Required for Contextual Memory Formation
Authors: Ramamoorthi Kartik , Fropf Robin , Belfort Gabriel M. , Fitzmaurice Helen L. , McKinney Ross M. , Neve Rachael L. , Otto Tim , Lin Yingxi
Published: December 2011

A transcription factor dependent on electrical activity regulates genes involved in long-term memory formation.
Comment on “Nocturnality in Dinosaurs Inferred from Scleral Ring and Orbit Morphology”
Authors: Hall Margaret I. , Kirk E. Christopher , Kamilar Jason M. , Carrano Matthew T.
Published: December 2011

Schmitz and Motani (Reports, 6 May 2011, p. 705) claimed to definitively reconstruct activity patterns of Mesozoic archosaurs using the anatomy of the orbit and scleral ring. However, we find serious flaws in the data, methods, and interpretations of this study. Accordingly, it is not yet possible to reconstruct the activity patterns of most fossil archosaurs with a high degree of confidence.
The Ribosome Modulates Nascent Protein Folding
Authors: Kaiser Christian M. , Goldman Daniel H. , Chodera John D. , Tinoco Ignacio , Bustamante Carlos
Published: December 2011

Single-molecule studies show that the ribosome promotes efficient folding of a two-domain protein.
How a DNA Polymerase Clamp Loader Opens a Sliding Clamp
Authors: Kelch Brian A. , Makino Debora L. , O’Donnell Mike , Kuriyan John
Published: December 2011

Crystal structures show how the sliding clamp that facilitates processive replication is loaded onto DNA.
A Cultured Greigite-Producing Magnetotactic Bacterium in a Novel Group of Sulfate-Reducing Bacteria
Authors: Lefèvre Christopher T. , Menguy Nicolas , Abreu Fernanda , Lins Ulysses , Pósfai Mihály , Prozorov Tanya , Pignol David , Frankel Richard B. , Bazylinski Dennis A.
Published: December 2011

The crystal structure of biomineralized magnetic nanocrystals depends on environmental and genetic factors.
Pigeons on Par with Primates in Numerical Competence
Authors: Scarf Damian , Hayne Harlene , Colombo Michael
Published: December 2011

Pigeons’ ability to use abstract numerical rules appears identical to that of monkeys.
Fear Erasure in Mice Requires Synergy Between Antidepressant Drugs and Extinction Training
Authors: Karpova Nina N. , Pickenhagen Anouchka , Lindholm Jesse , Tiraboschi Ettore , Kulesskaya Natalia , Ágústsdóttir Arna , Antila Hanna , Popova Dina , Akamine Yumiko , Sullivan Regina , Hen René , Drew Liam J. , Castrén Eero
Published: December 2011

Long-term loss of fearful memories can be achieved through a combination of antidepressant drugs and exposure therapy.
Blood-Brain Barrier Differentiation
Authors: Engelhardt Britta
Published: December 2011

A factor secreted by astrocytes is identified that controls the barrier characteristics of central nervous system microvascular endothelial cells.
Science Stays on Track in Last-Minute Spending Bill
Authors: Cho Adrian , Kaiser Jocelyn , Malakoff David
Published: December 2011

Last week's $915 billion spending bill for fiscal year 2012 treats science as well as, if not better than, most other federal activities.
New Hope for a Devastating Neurological Disorder
Authors: Miller Greg
Published: December 2011

Scientists have identified a drug that, in mice, fixes the genetic defect behind Angelman syndrome, which robs victims of speech and leaves them with intellectual disabilities, movement and balance problems.
Megaquake Heightened the Risk to Tokyo
Authors: Kerr Richard A.
Published: December 2011

Researchers reported at the meeting that the redistributed stress of March's magnitude-9 Tohoku earthquake activated distant, long-quiescent faults, the first time that has been recorded.
Comparison between Elecsys HBsAg II and Architect HBsAg QT Assays for Quantification of Hepatitis B Surface Antigen among Patients Coinfected with HIV and Hepatitis B Virus
Authors: Maylin Sarah , Boyd Anders , Delaugerre Constance , Zoulim Fabien , Lavocat Fabien , Simon François , Girard Pierre-Marie , Lacombe Karine
Published: December 2011

Hepatitis B surface antigen (HBsAg) quantification has been steadily gaining interest as a clinical marker of therapeutic efficacy, for which two commercial assays are currently available: Architect HBsAg QT (Architect) and Elecsys HBsAg II (Elecsys). HBsAg quantification was evaluated using both assays in 126 human immunodeficiency virus (HIV) and hepatitis B virus (HBV)-coinfected patients initiating treatment with tenofovir dipivoxil fumarate. Linear regression and correlation were used to establish the relationship between the two methods. Bland-Altman analysis was performed to determine mean between-assay difference and limits of agreement (LOA) (±2 standard deviations [SD]) both overall and stratified on HBV (hepatitis B envelope antigen [HBeAg] status, replication, genotype, HBV mutants) or HIV (CD4+cell count) cofactors. There was a significant correlation between Elecsys and Architect assays (correlation coefficient,r= 0.959;P< 0.001). HBsAg quantification using the Elecsys assay was on average 0.200 log10IU/ml (LOA, −0.500, 0.800) higher than that using Architect, which was consistent across levels of CD4+cell count, presence of precore and YMDD mutations, and HBeAg status. A slightly larger mean between-assay difference was observed with genotypes A and G (0.196 and 0.201, respectively) versus HBV genotypes D and E (0.036 and 0.030, respectively). Mutations on the S region at position s120/s145 were the only determinant in which the mean between-assay difference in HBsAg quantification was lower than the null value (−0.078). In conclusion, the Elecsys assay, with automatic on-board dilution, is capable of quantifying serum HBsAg levels in HIV-HBV-coinfected patients, with very high correlation with the Architect assay.
Differentiation of the Seven Major Lyssavirus Species by Oligonucleotide Microarray
Authors: Xi Jin , Guo Huancheng , Feng Ye , Xu Yunbin , Shao Mingfu , Su Nan , Wan Jiayu , Li Jiping , Tu Changchun
Published: December 2011

An oligonucleotide microarray, LyssaChip, has been developed and verified as a highly specific diagnostic tool for differentiation of the 7 major lyssavirus species. As with conventional typing microarray methods, the LyssaChip relies on sequence differences in the 371-nucleotide region coding for the nucleoprotein. This region was amplified using nested reverse transcription-PCR primers that bind to the 7 major lyssaviruses. The LyssaChip includes 57 pairs of species typing and corresponding control oligonucleotide probes (oligoprobes) immobilized on glass slides, and it can analyze 12 samples on a single slide within 8 h. Analysis of 111 clinical brain specimens (65 from animals with suspected rabies submitted to the laboratory and 46 of butchered dog brain tissues collected from restaurants) showed that the chip method was 100% sensitive and highly consistent with the “gold standard,” a fluorescent antibody test (FAT). The chip method could detect rabies virus in highly decayed brain tissues, whereas the FAT did not, and therefore the chip test may be more applicable to highly decayed brain tissues than the FAT. LyssaChip may provide a convenient and inexpensive alternative for diagnosis and differentiation of rabies and rabies-related diseases.
Loop-Mediated Isothermal Amplification Compared to Real-Time PCR and Enzyme Immunoassay for Toxigenic Clostridium difficile Detection
Authors: Boyanton Bobby L. , Sural Preethi , Loomis Caroline R. , Pesta Christine , Gonzalez-Krellwitz Laura , Robinson-Dunn Barbara , Riska Paul
Published: December 2011

Clostridium difficile
infection is the primary cause of health care-associated diarrhea. While most laboratories have been using rapid antigen tests for detecting
C. difficile
toxins, they have poor sensitivity; newer molecular methods offer rapid results with high test sensitivity and specificity. This study was designed to compare the performances of two molecular assays (Meridian
illumigene
and BD GeneOhm) and two antigen assays (Wampole Quik Chek Complete and TechLab Tox A/B II) to detect toxigenic
C. difficile
. Fecal specimens from hospitalized patients (
n
= 139) suspected of having
C. difficile
infection were tested by the four assays. Nine specimens were positive and 109 were negative by all four methods. After discrepant analysis by toxigenic culture (
n
= 21), the total numbers of stool specimens classified as positive and negative for toxigenic
C. difficile
were 21 (15%) and 118 (85%), respectively. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were as follows: GeneOhm (95.2%, 100%, 100%, and 99.2%),
illumigene
(95.2%, 96.6%, 83.3%, and 99.2%), Tox A/B II (52.4%, 97.5%, 78.6%, and 92.4%), and Quik Chek Complete (47.6%, 100%, 100%, and 91.9%). The
illumigene
assay performed comparably to the GeneOhm assay with a slight decrease in test specificity; the sensitivities of both far exceeded those of the antigen assays. The clinical characteristics of the concordant and discrepant study patients were similar, including stool consistency and frequency. In the era of rapid molecular-based tests for toxigenic
C. difficile
, toxin enzyme immunoassays (EIAs) should no longer be considered the standard of care.
Heteroresistance to Cephalosporins and Penicillins in Acinetobacter baumannii
Authors: Hung Kuei-Hsiang , Wang Ming-Cheng , Huang Ay-Huey , Yan Jing-Jou , Wu Jiunn-Jong
Published: December 2011

Heteroresistance to antimicrobial agents may affect susceptibility test results and therapeutic success. In this study, we investigated heteroresistance to cephalosporins and penicillins in
Acinetobacter baumannii
, a major pathogen causing nosocomial infections. Two
A. baumannii
isolates exhibited heteroresistance to ampicillin-sulbactam, ticarcillin-clavulanic acid, cefepime, and cefpirome, showing a distinct colony morphology of circular rings within the inhibition halos. Pulsed-field gel electrophoresis (PFGE) and outer membrane protein (OMP) analysis demonstrated that subpopulations around the disks/Etest strips and the original strains all belonged to the same PFGE type and OMP profile. Population analysis profile (PAP) showed the presence of heteroresistant subpopulations with high cefepime resistance levels in two isolates (008 and 328). Interestingly,
A. baumannii
008 contained two peaks: one was grown in the presence of up to 1 μg of cefepime/ml, the other apparently occurred when the concentration of cefepime was raised to 256 μg/ml. After serial passages without exposure to cefepime, the PAP curve maintained the same trend observed for the original strain of
A. baumannii
008. However, the PAP curve showed a shift to relatively lower cefepime resistance (from 256 to 64 μg/ml) in
A. baumannii
328 after 10 passages in antibiotic-free Mueller-Hinton agar plates. Convergence to a monotypic resistance phenotype did not occur. Growth rate analysis revealed that slower growth in resistant subpopulations may provide a strategy against antibiotic challenge. To our knowledge, this is the first report of heteroresistance to cephalosporins and penicillins in
A. baumannii
.
Detection and Measurement of Fungal Burden in a Guinea Pig Model of Invasive Pulmonary Aspergillosis by Novel Quantitative Nested Real-Time PCR Compared with Galactomannan and (1,3)-β-
d
-Glucan Detection
Authors: Lengerova Martina , Kocmanova Iva , Racil Zdenek , Hrncirova Kristyna , Pospisilova Sarka , Mayer Jiri , Najvar Laura K. , Wiederhold Nathan P. , Kirkpatrick William R. , Patterson Thomas F.
Published: December 2011

We developed and assessed the diagnostic value of a novel quantitative nested real-time (QNRT) PCR assay targeting the internal transcribed spacer region of ribosomal DNA (rDNA) in a guinea pig model of invasive pulmonary aspergillosis. Groups of 5 immunosuppressed animals that were infected using an aerosol chamber with
Aspergillus fumigatus
conidia were humanely terminated 1 h postinoculation and at days 3, 5, 7, and 11 postchallenge, and lung tissue, bronchoalveolar lavage (BAL) fluid, whole blood, and serum samples were collected. The QNRT PCR results obtained with the serum and BAL fluid were compared to those achieved with galactomannan and (1→3)-β-
d
-glucan assays. High fungal burden levels were detected by QNRT PCR in both lung tissue and BAL fluid in all infected animals at each time point, and the sensitivity of each assay in BAL fluid was 100% by day 3 and remained so through the remainder of the study. The sensitivity of detection of fungi in whole blood and serum samples was significantly lower, and some samples remained negative by all three assays despite the advanced stage of the infection. From these data, we can conclude that this novel QNRT PCR method was highly sensitive for the detection of
A. fumigatus
from different types of samples in this model. In addition, BAL fluid samples appeared to be the most suitable for the early diagnosis of invasive pulmonary aspergillosis. When testing serum, the use of a combination of available assays may increase the possibility of early detection of this opportunistic mycosis.