bluuebunny/crossref_metadata_2025 huggingface dataset:
Detection and Identification of Aster Yellows Phytoplasma Associated with Lipstick Yellow Frond Disease in Malaysia
Authors: Naderali Neda , Vadamalai Ganesan , Tan Yee How , Nejat Naghmeh
Published: October 2013

Yellowing symptoms similar to coconut yellow decline phytoplasma disease were observed on lipstick palms (Cyrtostachys renda) in Selangor state, Malaysia. Typical symptoms were yellowing, light green fronds, gradual collapse of older fronds and decline in growth. Polymerase chain reaction assay was employed to detect phytoplasma in symptomatic lipstick palms. Extracted DNA was amplified from symptomatic lipstick palms by PCR using phytoplasma‐universal primer pair P1/P7 followed by R16F2n/R16R2. Phytoplasma presence was confirmed, and the 1250 bp products were cloned and sequenced. Sequence analysis indicated that the phytoplasmas associated with lipstick yellow frond disease were isolates of ‘Candidatus Phytoplasma asteris’ belonging to the 16SrI group. Virtual RFLP analysis of the resulting profiles revealed that these palm‐infecting phytoplasmas belong to subgroup 16SrI‐B and a possibly new 16SrI‐subgroup. This is the first report of lipstick palm as a new host of aster yellows phytoplasma (16SrI) in Malaysia and worldwide.
Factors that influence activities of daily living in the elderly with probable dementia
Authors: Ha E. , Kim K.
Published: October 2013

Accessible summary

The aim of the research was to identify the factors that influence activities of daily living (ADL) in the elderly with probable dementia. Factors that influenced ADL were faecal and urinary incontinence, regularity of exercise, MMSE‐KC score and stroke history.

The factors that affect ADL in the present study can serve as a basis to develop a multidisciplinary intervention programme with the aim of reducing admissions to long‐term care facilities by increasing the ability to perform ADL. Such interventions should also aim to improve physical and mental health statuses and promote social and interpersonal interactions. These activities promote cognitive function and contribute to help for prevention of dementia.

This study identified five factors influencing ADL that can guide researchers and nurses in developing strategies to improve ADL.

The purpose of this study was to identify the factors that influence activities of daily living (ADL) in the elderly with probable dementia. The participants were 152 older adults who voluntarily visited a hospital to participate in a national dementia free screening programme. General characteristics, health‐related characteristics, ADL, Mini‐Mental State Examination Korean Consortium (MMSE‐KC) and the Geriatric Depression Scale (GDS) score were evaluated in this study. The data were analysed using independent t‐tests, Pearson's correlation and stepwise multiple regression. The ADL score of the participants was 14.3, and 88.2% of the participants were severe cognitive disorder. ADL scores were positively related with MMSE‐KC scores (r = 0.35, P < 0.001) and negatively with GDS scores (r = –0.20, P = 0.014). Factors that influenced ADL were faecal and urinary incontinence, regularity of exercise, MMSE‐KC score and stroke history; these five variables explained 30.8% of the ADL score for the elderly with probable dementia. Multidisciplinary interventions are essential to improve the ADL and prevent deterioration of cognitive function in elderly patients with probable dementia.
Phylogenetic analysis of LSU and SSU rDNA group I introns of lichen photobionts associated with the genera Xanthoria and Xanthomendoza (Teloschistaceae, lichenized Ascomycetes)
Authors: Nyati Shyam , Bhattacharya Debashish , Werth Silke , Honegger Rosmarie
Published: October 2013

We studied group I introns in sterile cultures of selected groups of lichen photobionts, focusing on Trebouxia species associated with Xanthoria s. lat. (including Xanthomendoza spp.; lichen‐forming ascomycetes). Group I introns were found inserted after position 798 (Escherichia coli numbering) in the large subunit (LSU) rRNA in representatives of the green algal genera Trebouxia and Asterochloris. The 798 intron was found in about 25% of Xanthoria photobionts including several reference strains obtained from algal culture collections. An alignment of LSU‐encoded rDNA intron sequences revealed high similarity of these sequences allowing their phylogenetic analysis. The 798 group I intron phylogeny was largely congruent with a phylogeny of the internal transcribed spacer region, indicating that the insertion of the intron most likely occurred in the common ancestor of the genera Trebouxia and Asterochloris. The intron was vertically inherited in some taxa, but lost in others. The high‐sequence similarity of this intron to one found in Chlorella angustoellipsoidea suggests that the 798 intron was either present in the common ancestor of Trebouxiophyceae, or that its present distribution results from more recent horizontal transfers, followed by vertical inheritance and loss. Analysis of another group I intron shared by these photobionts at small subunit position 1512 supports the hypothesis of repeated lateral transfers of this intron among some taxa, but loss among others. Our data confirm that the history of group I introns is characterized by repeated horizontal transfers, and suggests that some of these introns have ancient origins within Chlorophyta.
Baseline Characteristics from an Ongoing Phase 3 Study of Collagenase Clostridium Histolyticum in Patients with Peyronie's Disease
Authors: Gelbard Martin , Hellstrom Wayne J.G. , McMahon Chris G. , Levine Laurence A. , Smith Ted , Tursi James , Kaufman Gregory , Goldstein Irwin
Published: October 2013

Introduction

Peyronie's disease (PD) is a localized penile collagen disorder of the tunica albuginea associated with significant physical deformity and psychological impairment. Current understanding of pretreatment characteristics in patients with chronic PD is limited by small samples, varied quality of assessments, and the lack of a PD-specific, validated measure of the psychosexual impact of PD.

Aims

Reporting baseline demographic and disease characteristics of the large multinational cohort of subjects with chronic PD who participated in the collagenase clostridium histolyticum (CCH, an investigational intralesional injection and minimally invasive intervention) phase 3 clinical study program. Findings from well-defined assessments, including the Peyronie's Disease Questionnaire (PDQ), the first validated PD-specific patient-reported measure of psychosexual impact, are reported.

Methods

Subjects included men ≥18 years old with PD symptoms ≥12 months and penile deformity between 30° and 90°. Analysis data included demographics, disease history, and psychosexual impact.

Main Outcome Measures

Penile deformity, disease symptoms, the International Index of Erectile Function, and the PDQ were assessed.

Results

Eight hundred thirty-two subjects were enrolled from 64 sites across the United States and Australia. The mean age was 57.7 years; mean PD duration was 4.1 years. The majority of subjects had penile deformity ≤60° (77.3%); mean penile deformity was 50.5°. Subjects reported having intercourse a mean of 10.2 times in the previous 3 months, 70.8% reported difficulty in performing vaginal intercourse, and 80.4% reported less frequent vaginal intercourse. Approximately 71.5% of subjects with severe (>60°) and 58.1% of subjects with mild/moderate (≤60°) penile deformity were “very bothered” or “extremely bothered” upon last look at their erect penis (P = 0.0041), as measured by the PDQ.

Conclusions

These data add to the body of knowledge regarding the clinical impact of chronic phase PD, including the PD-specific patient-reported psychosexual symptoms, using a large multinational chronic PD cohort in the CCH phase 3 clinical program. Gelbard M, Hellstrom WJG, McMahon CG, Levine LA, Smith T, Tursi J, Kaufman G, and Goldstein I. Baseline characteristics from an ongoing phase 3 study of collagenase clostridium histolyticum in patients with Peyronie's disease. J Sex Med 2013;10:2822–2831.
Antiviral efficacy of entecavir in nucleos(t)ide‐naïve patients of Black/African descent with chronic hepatitis B
Authors: Jeffers L. , Van Rensburg C. J. , Banks A. , Schechter M. , Schmidt S. J. , Hu W. , Llamoso C. , Parana R.
Published: October 2013

This single‐arm, open‐label, descriptive study assessed the efficacy and safety of entecavir (ETV) in nucleos(t)ide‐naïve Black/African American patients with chronic hepatitis B (CHB), a patient population underrepresented in ETV registration trials. Forty patients with HBeAg(+) or HBeAg(−) compensated CHB of self‐described Black/African American race received ETV 0.5 mg daily for 52 weeks; 37 patients completed 52 weeks of treatment. At Week 48, 29/40 (72.5%, noncompleter = failure) patients achieved the primary endpoint of HBV DNA <50 IU/mL. Rates for HBeAg loss (11/22; 50%) and HBeAg seroconversion (9/22; 41%) were high, possibly due to the high HBV genotype A prevalence (70%). No patient experienced virological breakthrough. Samples for resistance testing were available in 6/8 patients with HBV DNA >50 IU/mL at Week 48 or last on‐treatment visit. No ETV resistance was detected. The safety profile of ETV was consistent with that observed in ETV registration trials. This study shows that in Black/African American patients with CHB, ETV was well tolerated and demonstrated comparable antiviral efficacy to that observed in White and Asian patients in ETV Phase III studies.
Diagnosis of Spontaneous Canine Hyperadrenocorticism: 2012 ACVIM Consensus Statement (Small Animal)
Authors: Behrend E.N. , Kooistra H.S. , Nelson R. , Reusch C.E. , Scott‐Moncrieff J.C.
Published: October 2013

This report offers a consensus opinion on the diagnosis of spontaneous canine hyperadrenocorticism. The possibility that a patient has hyperadrenocorticism is based on the history and physical examination. Endocrine tests should be performed only when clinical signs consistent with HAC are present. None of the biochemical screening or differentiating tests for hyperadrenocorticism are perfect. Imaging can also play a role. Awareness of hyperadrenocorticism has heightened over time. Thus, case presentation is more subtle. Due to the changes in manifestations as well as test technology the Panel believes that references ranges should be reestablished. The role of cortisol precursors and sex hormones in causing a syndrome of occult hyperadrenocorticism remains unclear.
Epithelial‐to‐mesenchymal transition is involved in BCNU resistance in human glioma cells
Authors: Yan Yong‐Rong , Xie Qiang , Li Feng , Zhang Yong , Ma Ji‐Wei , Xie Si‐Ming , Li Hai‐Ying , Zhong Xue‐Yun
Published: October 2013

Chemotherapy has been considered as an effective treatment for malignant glioma; however, it becomes increasingly ineffective with tumor progression. Epithelial‐to‐mesenchymal transition (EMT) is a process whereby cells acquire morphologic and molecular alterations that facilitate tumor metastasis and progression. Emerging evidence associates chemoresistance with the acquisition of EMT in cancer. However, it is not clear whether this phenomenon is involved in glioma. We used the previously established human glioma cell lines SWOZ1, SWOZ2 and SWOZ2‐BCNU to assess cellular morphology, molecular changes, migration and invasion. We found that BCNU‐resistant cells showed multiple drug resistance and phenotypic changes consistent with EMT, including spindle‐shaped morphology and enhanced pseudopodia formation. Decreased expression of the epithelial adhesion molecule E‐cadherin and increased expression of the mesenchymal marker vimentin were observed in BCNU‐resistant SWOZ1 and SWOZ2‐BCNU cells compared to SWOZ2 cells. Migratory and metastatic potentials were markedly enhanced in SWOZ1 and SWOZ2‐BCNU cells compared to SWOZ2 cells. These data suggest that there is a possible link between drug resistance and EMT induction in glioma cells. Gaining further insight into the mechanisms underlying chemoresistance and EMT may enable the restoration of chemosensitivity or suppression of metastasis.
Psychological traits influence autonomic nervous system recovery following esophageal intubation in health and functional chest pain
Authors: Farmer A. D. , Coen S. J. , Kano M. , Worthen S. F. , Rossiter H. E. , Navqi H. , Scott S. M. , Furlong P. L. , Aziz Q.
Published: October 2013

Background

Esophageal intubation is a widely utilized technique for a diverse array of physiological studies, activating a complex physiological response mediated, in part, by the autonomic nervous system (ANS). In order to determine the optimal time period after intubation when physiological observations should be recorded, it is important to know the duration of, and factors that influence, this ANS response, in both health and disease.

Methods

Fifty healthy subjects (27 males, median age 31.9 years, range 20–53 years) and 20 patients with Rome III defined functional chest pain (nine male, median age of 38.7 years, range 28–59 years) had personality traits and anxiety measured. Subjects had heart rate (HR), blood pressure (BP), sympathetic (cardiac sympathetic index, CSI), and parasympathetic nervous system (cardiac vagal tone, CVT) parameters measured at baseline and in response to per nasum intubation with an esophageal catheter. CSI/CVT recovery was measured following esophageal intubation.

Key Results

In all subjects, esophageal intubation caused an elevation in HR, BP, CSI, and skin conductance response (SCR; all p < 0.0001) but concomitant CVT and cardiac sensitivity to the baroreflex (CSB) withdrawal (all p < 0.04). Multiple linear regression analysis demonstrated that longer CVT recovery times were independently associated with higher neuroticism (p < 0.001). Patients had prolonged CSI and CVT recovery times in comparison to healthy subjects (112.5 s vs 46.5 s, p = 0.0001 and 549 s vs 223.5 s, p = 0.0001, respectively).

Conclusions & Inferences

Esophageal intubation activates a flight/flight ANS response. Future studies should allow for at least 10 min of recovery time. Consideration should be given to psychological traits and disease status as these can influence recovery.
Sphenomandibular ligament calcification causing progressive restriction of mouth opening: case report and literature review
Authors: Salha R. , Shah J. , Sidebottom A.J.
Published: October 2013

A 46‐year old male presented with a 3‐year history of restricted mouth opening following inferior alveolar block injections for dental treatment. An initial magnetic resonance imaging and subsequent three‐dimensional computed tomography scans reported the cause as lateral pterygoid calcification and temporalis muscle calcification, respectively. Physiotherapy was initially helpful but relapse occurred. Intraoperatively coronoidectomy was unsuccessful, and it was discovered that he had fibrosis and calcification of the sphenomandibular ligament. Release of this band improved his opening, and this has been maintained for 1 year.
Gene flow from transgenic oilseed Brassica juncea (L.) Czern. into weedy Sinapis arvensis L. (wild mustard)
Authors: Warwick Suzanne I. , Martin Sara L.
Published: October 2013

Gene flow from acetolactate synthase‐resistant (HR) Brassica juncea oilseed canola to related weed, Sinapis arvensis (density 1 plant/m2) was assessed in a 100 m2 field plot of HR B. juncea. Two HR F1 hybrids (H1 and H2) were detected among 109 951 seedlings screened with imazethapyr (hybridization frequency – 1.8 × 10−5). Hybridity was confirmed using flow cytometry, B. juncea‐specific amplified fragment length polymorphisms (AFLPs) markers, genomic in situ hybridization (GISH) and PCR‐based detection of B. juncea's HR gene. H1 and H2 had 2n = 27 and 2n = 45 chromosomes, corresponding 3x (SrAB) and 5x (SrAABB) genomic structures and reduced male fertility, 3.2 and 16.6% pollen viability, respectively. H1 was self‐incompatible, whereas H2 set seed when selfed (B. juncea trait). Selfed F2, F3 and F4 plants showed HR trait persistence and vigorous growth and high (80–100%) pollen fertility in 22% and 39% of the F2 and F3 plants, respectively. No progeny were obtained from F1, F2 or F3 hybrids × S. arvensis backcrosses, suggesting the likelihood of introgression of traits is low to negligible.
Monopoly Versioning of Information Goods When Consumers Have Group Tastes
Authors: Wei Xueqi (David) , Nault Barrie R.
Published: October 2013

Large sunk costs of development, negligible costs of reproduction, and distribution resulting in economies of scale distinguish information goods from physical goods. Versioning is a way firms may take advantage of these properties. However, in a baseline model where consumers differ in their tastes for quality, an information goods monopolist only offers one version, and this differs from what we observe in practice. We explore formulations that add features to the baseline model that result in a monopolist offering multiple versions. We examine versioning where consumers differ in individual tastes for quality, and groups of consumers that share the same group taste are delineated by segments of individual tastes. We find that if groups have mutually exclusive characteristics—a horizontal dimension—that they value relative to the shared characteristics, then versioning is optimal. Consequently, any horizontal differentiation in product line design favors versioning. In addition, when group tastes are hierarchical such that higher taste groups value characteristics that lower taste groups value but not vice versa—a vertical dimension—as long as the valuations of the higher and adjacent lower taste group are sufficiently close, then versioning is also optimal. Our conditions, which also help determine how many versions are optimal, are based on exogenously defined parameters so that it is feasible to check them in practice.
Risk Assessment of Multistate Progression of Breast Tumor with State‐Dependent Genetic and Environmental Covariates
Authors: Wu Yi‐Ying , Yen Ming‐Fang , Yu Cheng‐Ping , Chen Hsiu‐Hsi
Published: October 2013

Few studies have focused on the different roles risk factors play in the multistate temporal natural course of breast cancer. We proposed a three‐state Markov regression model to predict the risk from free of breast cancer (FBC) to the preclinical screen‐detectable phase (PCDP) and from the PCDP to the clinical phase (CP). We searched the initiators and promoters affecting onset and subsequent progression of breast tumor to build up a three‐state temporal natural history model with state‐dependent genetic and environmental covariates. This risk assessment model was applied to a 1 million Taiwanese women cohort. The proposed model was verified by external validation with another independent data set. We identified three kinds of initiators, including the BRCA gene, seven single nucleotides polymorphism, and breast density. ER, Ki‐67, and HER‐2 were found as promoters. Body mass index and age at first pregnancy both played a role. Among women carrying the BRCA gene, the 10‐year predicted risk for the transition from FBC to CP was 25.83%, 20.31%, and 13.84% for the high‐, intermediate‐, and low‐risk group, respectively. The corresponding figures were 1.55%, 1.22%, and 0.76% among noncarriers. The mean sojourn time of staying at the PCDP ranged from 0.82 years for the highest risk group to 6.21 years for the lowest group. The lack of statistical significance for external validation () revealed the adequacy of our proposed model. The three‐state model with state‐dependent covariates of initiators and promoters was proposed for achieving individually tailored screening and also for personalized clinical surveillance of early breast cancer.
Longin and GAF Domains: Structural Evolution and Adaptation to the Subcellular Trafficking Machinery
Authors: De Franceschi Nicola , Wild Klemens , Schlacht Alexander , Dacks Joel B. , Sinning Irmgard , Filippini Francesco
Published: October 2013

Endomembrane trafficking is one of the most prominent cytological features of eukaryotes. Given their widespread distribution and specialization, coiled‐coil domains, coatomer domains, small GTPases and Longin domains are considered primordial ‘building blocks’ of the membrane trafficking machineries. Longin domains are conserved across eukaryotes and were likely to be present in the Last Eukaryotic Common Ancestor. The Longin fold is based on the α‐β‐α sandwich architecture and a unique topology, possibly accounting for the special adaptation to the eukaryotic trafficking machinery. The ancient Per ARNT Sim (PAS) and cGMP‐specific phosphodiesterases, Adenylyl cyclases and FhlA (GAF) family domains show a similar architecture, and the identification of prokaryotic counterparts of GAF domains involved in trafficking provides an additional connection for the endomembrane system back into the pre‐eukaryotic world. Proteome‐wide, comparative bioinformatic analyses of the domains reveal three binding regions (A, B and C) mediating either specific or conserved protein–protein interactions. While the A region mediates intra‐ and inter‐molecular interactions, the B region is involved in binding small GTPases, thus providing an evolutionary connection among major building blocks in the endomembrane system. Finally, we propose that the peculiar interaction surface of the C region of the Longin domain allowed it to extensively integrate into the endomembrane trafficking machinery in the earliest stages of building the eukaryotic cell.
Identification and characterization of a novel porcine endothelial cell‐specific Tie1 promoter
Authors: Chen Tao , Wang Jiaqiang , Xue Binghua , Kong Qingran , Liu Zhonghua , Yu Bo
Published: October 2013

Background

The use of a transgenic pig for xenotransplantation and as a cardiovascular disease model has caught much attention in the past decades. The vascular endothelial cell is the primary modification target for the application of genetically modified pigs in this field. However, the powerful porcine endothelial cell‐specific promoter is still so rare that the mouse and human promoters are commonly used. In the study, the porcine Tie1 (sTie1) promoter was identified and characterized as a potential endothelial cell‐specific promoter to generate a cardiovascular disease model.

Methods

Tie1 promoters with different lengths of 5′‐regulatory regions were cloned, and major putative DNA‐binding motifs were mutated by site‐directed mutagenesis. All fragments were ligated into the luciferase reporter system and were transiently transfected into endothelial cells to identify luciferase activity using a dual luciferase reporter assay.

Results

The luciferase activities of sTie1 promoters with different lengths of the 5′‐regulatory region were tested. Results showed that the luciferase activity of the 1234‐bp sTie1 fragment was the strongest compared with that of others (P < 0.001). Site‐directed mutagenesis in transcription‐factor‐binding sites, including Ets, GATA, and AP2, verified their key roles in regulating transcription, especially sites Ets (‐103), GATA (‐211), and AP2 (‐3). The activities of Tie1 promoters from pig, human, and mouse were significantly different in pig iliac endothelial cells (PIECs) (P < 0.001), and the sTie1 promoter showed the highest activity. Moreover, sTie1 promoter activity could be detected in porcine embryo fibroblasts and skeletal muscle cells.

Conclusions

The sTie1 promoter shows a highly conserved sequence compared with the Tie1 promoters in human and mouse, but it has a greater activity in the porcine endothelial cell line than that of human and mouse promoters. Thus, sTie1 will be a valuable tool for generating a pig cardiovascular disease model.
The Danger of Piping Failure Due to Acoustic-Induced Fatigue in Infrequent Operations: Two Case Studies
Authors: Mohammed Al-Muslim Husain , Ibrahim Al-Nasri Nadhir , Al-Hashem Mohammad Y.
Published: October 2013

Failure in piping due to acoustic-induced fatigue can be considered catastrophic as it could happen only after a few minutes of operation. Acoustic-induced fatigue occurs mainly in gas piping systems with high velocity where high energy is dissipated through pressure reducing stations and pipe branch connections. It usually results in pipe through wall longitudinal cracks, pipe detachment from saddle supports, and complete shear off of branch connections. There are existing design criteria to avoid acoustic-induced fatigue based on comparison of generated power level to an acceptable power level. This criterion is normally used for the design of pressure relief and flare piping where high gas velocity exceeding 50% of the speed of sound (i.e., 0.5 Mach) is expected. However, acoustic-induced fatigue has been experienced in systems due to intermittent operations. Two case studies are presented in this paper. The first one is during a steam-out operation to clean a newly constructed steam header. During the cleaning operation, an orifice plate was used to control the flow in the steam header. Several pipe vents and drains failed due to fatigue in less than 1 h. The second case is for drainage of compressed natural gas during process upset condition. Because of the high level buildup in the liquefied gas separator vessel, the drain valve was opened to release the pressurized liquefied gas to the relief system to reduce the level buildup. Wall cracks and several pipe support detachments were found in the system after the upset condition. This paper presents the engineering analysis and material failure analysis conducted to find the root causes of the failures. Moreover, it highlights the recommendations and lessons learned from these two failures.
Performance of Hybrid Fin Heat Sinks for Thermal Control of Light Emitting Diode Lighting Modules
Authors: Joon Kim Kyoung
Published: October 2013

In this paper we introduce a hybrid fin heat sink (HFH) proposed for the thermal control of light emitting diode (LED) lighting modules. The HFH consists of the array of hybrid fins which are hollow pin fins having internal channels and integrated with plate fins. The thermal performance of the HFH under either natural or forced convection condition is both experimentally and numerically investigated, and then its performance is compared with that of a pin fin heat sink (PFH). The observed maximum discrepancies of the numerical prediction to the measurement for the HFH are 7% and 6% for natural and forced convection conditions. The reasonable discrepancies demonstrate the tight correlation between the numerical prediction and the measurement. The thermal performance of the HFH is found to be 12–14% better than the PFH for the natural convection condition. The better performance might be explained by the enlarged external surface and the internal flow via the channel of the HF. The reference HFH is about 14% lighter than the reference PFH. The better thermal performance and the lighter weight of the HFH show the feasibility as the promising heat sink especially for the thermal control of LED street and flood lighting modules.
Vibration Modes and Natural Frequency Veering in Three-Dimensional, Cyclically Symmetric Centrifugal Pendulum Vibration Absorber Systems
Authors: Shi Chengzhi , Parker Robert G.
Published: October 2013

This paper investigates the vibration mode structure of three-dimensional, cyclically symmetric centrifugal pendulum vibration absorber (CPVA) systems. The rotor in the system has two translational, one rotational, and two tilting degrees of freedom. The equations of motion for the three-dimensional model, including the rotor tilting, are derived to study the modes analytically and numerically. Only three mode types exist: rotational, translational-tilting, and absorber modes. The rotational and absorber modes have identical properties to those of in-plane models. Only the translational-tilting modes contain rotor tilting. The veering/crossing behavior between the eigenvalue loci is derived analytically.
Finite Element Transient Dynamic Analysis of Delaminated Composite Conical Shells Subject to Low Velocity Impact
Authors: Dey Sudip , Roy Manoj , Karmakar Amit
Published: October 2013

This paper investigates on the transient dynamic response of delaminated composite pretwisted shallow conical shells subjected to low velocity normal impact. Turbomachinery blades with low aspect ratio could be idealized as twisted rotating cantilever composite conical shells. To derive the dynamic equilibrium equation, Lagrange’s equation of motion is used for moderate rotational speeds neglecting the Coriolis effect. An eight noded isoparametric plate bending element is employed in the finite element formulation incorporating rotary inertia and effects of transverse shear deformation based on Mindlin’s theory. To satisfy the compatibility of deformation and equilibrium of resultant forces and moments at the delamination crack front a multipoint constraint algorithm is incorporated which leads to unsymmetric stiffness matrices. The modified Hertzian contact law which accounts for permanent indentation is utilized to compute the contact force, and the time dependent equations are solved by Newmark’s time integration algorithm. Parametric studies are conducted in respect of triggering parameters like location of delamination, angle of twist and velocity of impactor for the centrally impacted graphite-epoxy torsion stiff composite conical shells.
Health Monitoring of Gears Based on Vibrations by Support Vector Machine Algorithms
Authors: Bordoloi D. J. , Tiwari Rajiv
Published: October 2013

Health monitoring of gears is very critical for satisfactorily overall working of the complex machinery. Thus, the ability to detect gear faults and classify them based on their nature becomes very important aspect of health monitoring of machines. In this paper, SVM algorithms have been used for the multiclass prediction of faults with the help of time domain vibration signals obtained from the gearbox casing operated in a suitable speed range. Moreover, it tries to examine the performance of the SVM technique by optimizing its parameters on utilization of time domain data from multi-fault gear box. The SVM software was fed with the training data and testing data at similar operating speeds for three types of defects and no defect case, and classification ability of SVM was noted and found to be excellent. The sensitivity analysis of optimized parameters is studied and conclusions are drawn.
Voxel-Based Approach for Computation and Optimization of Unoccupied Space in CAD Assemblies
Authors: Swamy C. Saikrishna , Rajadhyaksha Rahul , Paul Nabarun
Published: October 2013

CAD designers constantly face challenges in optimizing the design space to reduce cost and improve aesthetics without compromising the components’ functionality in an assembly. Specifically, in the aerospace industry, there is a need to continuously accommodate more components in lesser space and also consume less weight. With an increased use of 3D CAD models to represent complex designs and assemblies in industries like automotive, aerospace, and in various electronic products, there is a need for a tool to review the CAD assemblies for space optimization at every stage of the design.

For effective space optimization, there is a need to quickly get an idea of the consumed and available space in the assembly. This will help the designer take effective decisions in placement of components such that the available space is effectively optimized. Currently designers adopt various tools like repeated sectioning, component box computation and summation to get an estimate of the available versus consumed space. The first approach is time consuming while the latter is not as accurate as required.

In this paper, we have adopted an approach based on voxelization or volumization of the 3D CAD models to compute the volume space occupied by the assembly and its components and also identify void spaces between the components in an assembly. The volume space is computed by fitting a voxel grid enclosing the 3D Model with uniform number of voxels along coordinate axes. The voxels are examined to identify whether there is material (or no material) and classify them as inside (material) or outside (no material) voxels and are grouped into finite regions. Once the model is discretized, the output can be post-processed to generate data for various applications — computing the wrap volume or consumed space of the complete assembly, identifying significant void spaces in the assembly, etc. A wrap volume is the volume of the package which would result if we hypothetically wrap the model under consideration with wrapping/packaging paper. Consumed-space is different from the material volume in that it includes additional space due to voids in the model, small inaccessible spaces, etc.

The approach is useful for design improvements through optimization of void spaces between components depending on the related use cases. In the present study, this methodology has been successfully tested on a few industrial components. Greater accuracy in space discretization can be achieved by increasing voxel resolution. This approach handles complex geometry including freeform surfaces and turns out to be useful in addressing the space optimization problems in industries dealing with complex assemblies.
A High-Loaded Supersonic Axial Compressor Aerodynamic Design Principle
Authors: Hu Yingjiao , Wang Songtao
Published: October 2013

Reviewed the historical development of the supersonic axial flow compressor, and gave an outlook for its future developments and research orientations. According to the internal flow characteristics of the conventional supersonic axial flow compressors, put forward a high load of supersonic axial compressor aerodynamic design principle. A preliminary design verification of the principle has been carried. The 3D viscous numerical simulation results show that, under the tip tangential speed 360m / s, has achieved a stage pressure ratio 2.3 with efficiency 86.5%. In addition, considering the rotor under impulse condition can get the maximum rotor total pressure ratio with high efficiency, a design principle has also been put forward to solve the high entrance Mach number problem of the downstream stator. But the numerical simulation results show that the multi-shock structure does not have any advantages to reduce the stator losses.
Laminar Burning Velocity of LPG-Air Mixture at Elevated Temperatures
Authors: Akram Mohammad , Saxena Priyank , Kumar Sudarshan
Published: October 2013

Laminar burning velocity of liquefied petroleum gas (LPG) air mixtures at high temperatures is extracted from the planar flames stabilized in the preheated meso-scale diverging channel. The experiments were carried out for a range of equivalence Computational predictions of burning velocity and detailed flame structure were performed using PREMIX code with USC mech 2.0. The present data are in very good agreement with both experimental and computational results available. Peak burning velocity was observed for slightly rich mixtures even at higher mixture temperatures. The minimum value of temperature exponent is observed for slightly rich mixtures.
Wave-Rotor Pressure-Gain Combustion Analysis for Power Generation and Gas Turbine Applications
Authors: Rajagopal Manikanda , Karimi Abdullah , Nalim Razi
Published: October 2013

A wave-rotor pressure-gain combustor (WRPGC) ideally provides constant-volume combustion and enables a gas turbine engine to operate on the Humphrey-Atkinson cycle. It exploits pressure (both compression and expansion) waves and confined propagating combustion to achieve pressure rise inside the combustor. This study first presents thermodynamic cycle analysis to illustrate the improvements of a gas turbine engine possible with a wave rotor combustor. Thereafter, non-steady reacting simulations are used to examine features and characteristics of a combustor rig that reproduces key features of a WRPGC.

In the thermodynamic analysis, performance parameters such as thermal efficiency and specific power are estimated for different operating conditions (compressor pressure ratio and turbine inlet temperature). The performance of the WRPGC is compared with the conventional unrecuperated and recuperated engines that operates on the Brayton cycle. Fuel consumption may be reduced substantially with WRPGC introduction, while concomitantly boosting power. Simulations have been performed of the ignition of propane by a hot gas jet and subsequent turbulent flame propagation and shock-flame interaction.
Quantitative Monte Carlo‐based holmium‐166 SPECT reconstruction
Authors: Elschot Mattijs , Smits Maarten L. J. , Nijsen Johannes F. W. , Lam Marnix G. E. H. , Zonnenberg Bernard A. , van den Bosch Maurice A. A. J. , Viergever Max A. , de Jong Hugo W. A. M.
Published: October 2013

Purpose:

Quantitative imaging of the radionuclide distribution is of increasing interest for microsphere radioembolization (RE) of liver malignancies, to aid treatment planning and dosimetry. For this purpose, holmium‐166 (166Ho) microspheres have been developed, which can be visualized with a gamma camera. The objective of this work is to develop and evaluate a new reconstruction method for quantitative 166Ho SPECT, including Monte Carlo‐based modeling of photon contributions from the full energy spectrum.

Methods:

A fast Monte Carlo (MC) simulator was developed for simulation of166Ho projection images and incorporated in a statistical reconstruction algorithm (SPECT‐fMC). Photon scatter and attenuation for all photons sampled from the full 166Ho energy spectrum were modeled during reconstruction by Monte Carlo simulations. The energy‐ and distance‐dependent collimator‐detector response was modeled using precalculated convolution kernels. Phantom experiments were performed to quantitatively evaluate image contrast, image noise, count errors, and activity recovery coefficients (ARCs) of SPECT‐fMC in comparison with those of an energy window‐based method for correction of down‐scattered high‐energy photons (SPECT‐DSW) and a previously presented hybrid method that combines MC simulation of photopeak scatter with energy window‐based estimation of down‐scattered high‐energy contributions (SPECT‐ppMC+DSW). Additionally, the impact of SPECT‐fMC on whole‐body recovered activities (Aest) and estimated radiation absorbed doses was evaluated using clinical SPECT data of six 166Ho RE patients.

Results:

At the same noise level, SPECT‐fMC images showed substantially higher contrast than SPECT‐DSW and SPECT‐ppMC+DSW in spheres ≥17 mm in diameter. The count error was reduced from 29% (SPECT‐DSW) and 25% (SPECT‐ppMC+DSW) to 12% (SPECT‐fMC). ARCs in five spherical volumes of 1.96–106.21 ml were improved from 32%–63% (SPECT‐DSW) and 50%–80% (SPECT‐ppMC+DSW) to 76%–103% (SPECT‐fMC). Furthermore, SPECT‐fMC recovered whole‐body activities were most accurate (Aest = 1.06 × A − 5.90 MBq, R2 = 0.97) and SPECT‐fMC tumor absorbed doses were significantly higher than with SPECT‐DSW (p = 0.031) and SPECT‐ppMC+DSW (p = 0.031).

Conclusions:

The quantitative accuracy of166Ho SPECT is improved by Monte Carlo‐based modeling of the image degrading factors. Consequently, the proposed reconstruction method enables accurate estimation of the radiation absorbed dose in clinical practice.
Draft Genome Sequence of Brucella melitensis Strain ADMAS-G1, Isolated from Placental Fluids of an Aborted Goat
Authors: Shome Rajeswari , Krithiga Natesan , Muttannagouda Revanasiddappa Biradar , Veeregowda Belamaranahalli Muniveerappa , Swati Sahay , Shome Bibek Ranjan , Vishnu Udayakumar , Sankarasubramanian Jagadesan , Sridhar Jayavel , Gunasekaran Paramasamy , Rahman Habibur , Rajendhran Jeyaprakash
Published: October 2013

Here, we report the draft genome sequence and annotation of the
Brucella melitensis
strain designated ADMAS-G1, isolated from placental fluids of an aborted goat. The length of the genome is 3,284,982 bp, with a 57.3% GC content. A total of 3,325 protein-coding genes and 63 RNA genes were predicted.
Genome Sequence of Human Herpesvirus 7 Strain UCL-1
Authors: Donaldson Callum D. , Clark Duncan A. , Kidd I. Michael , Breuer Judith , Depledge Daniel D.
Published: October 2013

The sequence of human herpesvirus 7 (HHV-7) strain UCL-1 was determined using target enrichment and next-generation sequencing methods. We have identified 86 putative open reading frames (ORFs), and comparative sequence analyses demonstrate that this strain is closely related to the previously sequenced HHV-7 strains RK and JI.
Huge undifferentiated fibroblastic sarcoma of the foot and lower leg: impact of diagnostic delay and discussion of an entity
Authors: Müller Cornelia S L , Pföhler Claudia , Kohn Dieter , Vogt Thomas
Published: October 2013

We report a case of a 40-year-old female patient with a huge fibroblastic differentiated sarcoma of the left foot. After sampling all clinical, pathological and imaging information, the case was presented to the interdisciplinary tumour conference. Further treatment and medical care took place in the department of orthopaedics and orthopaedic surgery of our university hospital. Treatment consisted of amputation of the left foot and lower leg as an extremity-preserving surgical procedure was not possible because clear surgical margins could not be achieved with preservation of a functional rest of ankle and foot. Till date, no metastases have occurred.
ON REYNOLDS' DILATANCY AND SHEAR BAND EVOLUTION: A NEW PERSPECTIVE
Authors: WALKER DAVID M. , VO KEVIN , TORDESILLAS ANTOINETTE
Published: October 2013

Dense granular media exhibit rich phenomenology when subject to imposed stresses and strains. This is a result of the many degrees of freedom present in an assembly of grains and the nonlinear interactions between the grains. Their complex behavior include the self-organization of load-bearing columnar structures known as force chains across a wide range of spatial scales. Behavior akin to phase transitions from a strong solid-like to a weak liquid-like response can also be observed with shear bands, i.e. regions where force chains collectively buckle, being the signature microstructure in this transition from the stable to the failure regime. An inherent aspect of shear bands and dense granular failure is the phenomenon of dilatancy, i.e. expansion in volume, when the material is subjected to a combined compression and shear. To understand the origins of dilatancy, it is useful to consider the granular material as a mixture of two components: grains and the interstitial material filling the voids or pores between the grains. The grains within a dense granular material respond to applied loads by rearranging to create local zones which contract and dilate. Extant studies of this mechanical response are typically focused on the solid skeleton, in particular, the topology of the network representing the physical contacts between grains. Here, we propose an alternative perspective which is to consider network representations of the evolving anisotropic pore space. We demonstrate how to construct pore space networks that express the local size of voids about a grain through network edge weights. We investigate sectors of the loading history when a percolating giant component of the pore space network exists. By defining two weight functions for edge properties, we: (i) discover via a recurrence plot-based analysis a temporal time scale for jamming–unjamming (contractant-dilatant) dynamics in shear bands; and show that (ii) the formation of a persistent shear band in response to the deformation places grains in a configuration predisposed to the efficient transport of interstitial material as evidenced by the location of percolating shortest path routes through the most dilatant sites. A proper understanding of the micromechanics of pore evolution with respect to shear bands and dilatancy is key to a range of applications such as modeling ground water flow, dewatering systems, carbon capture and sequestration.
DERIVATION OF ISOCHRONICITY CONDITIONS FOR QUASI-CUBIC HOMOGENEOUS ANALYTIC SYSTEMS
Authors: WU YUSEN , LI FENG , LI PEILUAN
Published: October 2013

In this article, we deal with the problems of characterizing isochronous centers for real planar quasi-cubic homogeneous analytic system. The technique is based on reducing the quasi-cubic analytic system into an analytic system. With the help of common computer algebra software-MATHEMATICA, we compute the period constants of the origin and obtain the necessary isochronous center conditions for the transformed system. Finally, we give a proof of the sufficiency by various methods. Similar results are less so far. Our work is new in terms of research about quasi-cubic analytic system and consists of the existing results related to cubic polynomial system as a special case. What is worth pointing out is that we offer a kind of interesting phenomenon that the exponent parameter λ controls the nonanalyticity of the studied system (5).
A FRAMEWORK FOR INTERNEURAL DYNAMICS IN A CEREBRAL CORTEX CENTER
Authors: BOYARSKY ABRAHAM , LI ZHENYANG , GÓRA PAWEŁ
Published: October 2013

We model the innervation dynamics of interneurons in a cerebral cortex center A between the time of initial sensory input and acquisition of a sustained steady state. The model assumes that interneurons in A are heavily interconnected allowing synchronization. This invites modeling the dynamics by means of a discrete time map. The model takes into account the influence of excitatory and inhibitory cells and reflects the architecture of synapses along the axons. The acquisition of a sustained chaotic state is characterized by means of a natural invariant probability measure. The time to attain this probability measure can be estimated.
Pressure–temperature estimates on the Tjeliken eclogite: new insights into the (ultra)-high-pressure evolution of the Seve Nappe Complex in the Scandinavian Caledonides
Authors: Majka Jarosław , Janák Marian , Andersson Barbro , Klonowska Iwona , Gee David G. , Rosén Åke , Kośmińska Karolina
Published: October 2013

The metamorphic evolution of the Tjeliken eclogite, occurring within the Seve Nappe Complex of northern Jämtland (Swedish Caledonides), is presented here. The prograde part of the pressure and temperature (
P–T
) path is inferred from the mineral inclusions (pargasitic amphibole) in garnet and intracrystalline garnet exsolutions in omphacite. Peak metamorphic conditions of 25–26 kbar at 650–700 °C are constrained from geothermobarometry for the peak-pressure assemblage garnet+omphacite+phengite+quartz+rutile, using the garnet–clinopyroxene Fe–Mg exchange thermometer in combination with the net-transfer reaction (6 diopside+3 muscovite=3 celadonite +2 grossular+pyrope) geobarometer, the average
P–T
method of Thermocalc and pseudosection modelling. Quartz inclusions with well-developed radial cracks were identified within omphacite, which suggest that the studied rock could have been buried down to the coesite stability field. Post-peak
P–T
evolution is inferred from diopside–plagioclase symplectites and amphibole coronas around garnet. Previous studies in northern Jämtland suggest a substantial gap between the
P–T
conditions of the Lower and Middle Seve nappes: 14–16 kbar and 550–680 °C and 20–30 kbar and 700–800 °C, respectively. The Tjeliken eclogite has been considered previously to be a part of Lower Seve by most authors, but the new
P–T
data suggest that it may be an isolated klippe of Middle Seve.
(Gordon E. Moore Award Presentation) Sensors Using AlGaN/GaN Based High Electron Mobility Transistor for Environmental and Bio-Applications
Authors: Ren Fan , Pearton S. J.
Published: October 2013

AlGaN/GaN high electron mobility transistor (HEMT) based sensors have been developed to analyze a wide variety of gases and biological agents for biomedical applications. The conducting 2DEG channel of GaN/AlGaN HEMTs is very close to the surface and extremely sensitive to adsorption of analytes. Examples of detecting breath cancer marker, carbon monoxide carbon dioxide, kidney injury molecule, and botulinum toxin are discussed in this paper.