bluuebunny/crossref_metadata_2025 huggingface dataset:
A simple approach to define Holocene sequence stratigraphy using borehole and cone penetration test data
Authors: Styllas Michael
Published: June 2013

Cone penetration testing has been widely used since the 1950s for determining the subsurface geotechnical conditions of unconsolidated sediments. This paper highlights the potential value of cone penetration testing as an aid to define the stratigraphic structure of Holocene sedimentary deposits. By calibrating cone penetration test logs with adjacent borehole logs and by utilizing all the available information produced during geotechnical surveying, stratigraphic models that accurately describe the vertical and lateral boundaries, as well as the stacking pattern, of Late Quaternary systems can be constructed. The widespread application and technical simplicity of cone penetration testing, combined with simple data interpretation via correlation with adjacent borehole logs, yield a useful and inexpensive tool for sedimentological investigations. This methodology is illustrated using data from 36 cone penetration tests and 11 boreholes on the Holocene deltaic plain of the Aliakmon River, Greece. Sedimentological and stratigraphic information from core log correlations, the spatial distribution of cone penetration test parameters, sediment grain size and per cent concentration of organic matter are utilized. The results suggest, that in sequence stratigraphic terms, the delta is divided into a lowstand systems tract composed by fluvial gravels and sands (U0) of Late Pleistocene age, as well as from red oxidized clays, and a transgressive systems tract represented by fluvial channel sands (U1), overlain by a thin transgressive sand sheet of coastal origin (U2), characterized by fining upward trends. The highstand systems tract is constituted by a variety of stratigraphic units (U3 to U7) and depositional environments, characterized by coarsening upward sequences, representing both aggradational and progradational facies, and dominated by the presence of three prograding wedges. Detailed definition of the thickness, vertical boundaries and stacking pattern of the resolved stratigraphic units, presented as a two‐dimensional stratigraphic model, demonstrates the applicability of the proposed method.
Klebsiella necrotizing soft tissue infections in liver transplant recipients: a case series
Authors: Rana M.M. , Sturdevant M. , Patel G. , Huprikar S.
Published: June 2013

Necrotizing soft tissue infections (NSTI) are rare but carry high mortality rates. NSTI with Klebsiella species have been previously described as associated with Klebsiella liver abscesses and endophthalmitis. Here, we describe 6 cases of NSTI in liver transplant recipients associated with Klebsiella pneumoniae, 4 of which were K. pneumoniae carbapenemase (KPC)‐producing K. pneumoniae (CRKP). Increased awareness of this emerging pathogen and its association with necrotizing skin and soft tissue infection is critical, as early recognition and debridement may improve survival. Antimicrobial treatment of CRKP infections remains an ongoing challenge and implementation of enhanced infection control measures is essential.
Feline sarcoptic mange in Taiwan: a case series of five cats
Authors: Huang Hui‐Pi , Lien Yu‐Hsin
Published: June 2013

Background

Sarcoptes scabiei infestation is rare in cats.

Objective

To report the clinical presentations and treatments of cats infested with S. scabiei.

Animals

Five cats that presented with progressive and nonresponsive crusting lesions on the concave and convex aspects of the pinnae are included in this series. Other dermatological manifestations recorded were crusts on the bridge of the nose (five of five), crusty pododermatitis (three of five), crusty lesions on the tail (one of five) and pruritic erythematous papules on the arms and/or thighs of the owners (five of five). None of the cats was living in a household with a dog.

Methods

Sarcoptic (S. scabiei) mange was diagnosed based on the identification of S. scabiei in deep skin scrapings. A spot‐on application of 1.0% moxidectin and 10% imidacloprid (0.1 mL/kg) was administered every 2 weeks for three applications. All cats were re‐evaluated at the time of treatment.

Results

All five cats and their owners improved after the first application and reached clinical remission after the third application. Deep skin scrapings from all cats were negative for S. scabiei after the first application. No clinical adverse effects or abnormalities on routine blood tests were noted during the study period. No reinfestation was reported during the follow‐up period of 6 months after treatment.

Conclusion

Although sarcoptic mange is rare in cats, it should be considered as a differential diagnosis for cats presenting with crusting lesions on the pinnae and nose and crusty pododermatitis. A spot‐on preparation of moxidectin and imidacloprid was used successfully to treat cats with S. scabiei infestation.
Beech-mast crop evaluation in Kněhyně forest complex (Beskydy Mts. Czech Republic) as a food supply for granivorous rodents
Authors: Heroldová M. , Suchomel J. , Purchart L. , Čepelka L.
Published: June 2013

Good beech-mast crop is important not only for beech forest regeneration but it stimulates population abundances of granivorous animals. Abundant beech-mast crop was observed in autumn 2011 in Beskydy Mts. Mean mass of healthy beech-mast on Kněhyně Mts complex was 92 g.m−2 which represents 390 pieces (pc)/m2. That was why diet supply for granivorous forest rodents, in means of current biomass of beech-mast, was ascertained in 5 beech stands. At each locality, beech stands were chosen to represent Kněhyně Mt. beech forests and differ in age structure and the elevation. Biomass of beech-mast crop collected from the lowest elevation (5th vegetation tier) was higher (as to number of beechnuts/m2) and heavier (g/m2) compared to the highest elevation one (8th vegetation tier). The beech forests from the lower altitude may have a better condition for the beech seeds production. As the granivorous species are peeling the beechnuts, so the peeled diet supply of beech-mast was also stated. This should be considered if calculating diet consumption of particular rodent species.
Water availability effect on transpiration of the Norway spruce forest stand: a case study
Authors: Bužková R. , Pokorný R.
Published: June 2013

We have studied Norway spruce stand transpiration in socially differentitated forest in dense and sparse part. During dry conditions, codominant trees in forest sparse part transpired about 85 % of total stand transpiration and in forest dense 92 %. Forests socially differentitated and less dense has a better biomass production potential with exception of extremely low soil water availability.
Change of stand structure in upper tree line caused by disturbances
Authors: Gubka K. , Pittner J.
Published: June 2013

In 2002, the series of 4 permanent research plots of different altitudes (difference 100 m) was established in forest stand that is the part of upper tree line. In the plots we registered the quantitative and qualitative biometric characteristics of individual trees. The results showed that the stand is relatively statically stable (sufficient parameters of crown ratio and slenderness). The studied stand had adequate density and the number of stems was increasing with the decreasing altitude (from 1,460 to 1,260 m a.s.l.). The stand was comparable with the model one (yield tables) regarding the quantitative as well as qualitative parameters.

After the wind disturbance in 2004, two studied plots in higher altitudes were totally destroyed. In the time of repeated measurements (in 2010) the negative impact of the bark-beetle outbreak began to be visible. It was reflected in increased mortality of spruce also in the research plots situated in lower altitudes of studied stand. We confirmed that the neglect of forest hygiene and adequate silvicultural treatment leads to decline of stand condition and functionality in the upper tree line forests.
Optimal Design of a Damped Single Degree of Freedom Platform for Vibration Suppression in Harmonically Forced Undamped Systems
Authors: Issa Jimmy S.
Published: June 2013

Vibration reduction in harmonically forced undamped systems is considered using a new vibration absorber setup. The vibration absorber is a platform that is connected to the ground by a spring and damper. The primary system is attached to the platform, and the optimal parameters of the latter are obtained with the aim of minimizing the peaks of the primary system frequency response function. The minimax problem is solved using a method based on invariant points of the objective function. For a given mass ratio of the system, the optimal tuning and damping ratios are determined separately. First, it is shown that the objective function passes through three invariant points, which are independent of the damping ratio. Two optimal tuning ratios are determined analytically such that two of the three invariant points are equally leveled. Then, the optimal damping ratio is obtained such that the peaks of the frequency response function are equally leveled. The optimal damping ratio is determined in a closed form, except for a small range of the mass ratio, where it is calculated numerically from two nonlinear equations. For a range of mass ratios, the optimal solution obtained is exact, because the two peaks coincide with the two equally leveled invariant points. For the remaining range, the optimal solution is semiexact. Unlike the case of the classical absorber setup, where the absorber performance increases with increasing mass ratios, it is shown that an optimal mass ratio exists for this setup, for which the absorber reaches its utmost performance. The objective function is shown in its optimal shape for a range of mass ratios, including its utmost shape associated with the optimal mass ratio of the setup.
Crack Identification of Cantilever Plates Based on a Kriging Surrogate Model
Authors: Gao Haiyang , Guo Xinglin , Ouyang Huajiang , Han Fang
Published: June 2013

This work presents an effective method to identify the tip locations of an internal crack in cantilever plates based on a Kriging surrogate model. Samples of varying crack parameters (tip locations) and their corresponding root mean square (RMS) of random responses are used to construct the initial Kriging surrogate model. Moreover, the pseudo excitation method (PEM) is employed to speed up the spectral analysis. For identifying crack parameters based on the constructed Kriging model, a robust stochastic particle swarm optimization (SPSO) algorithm is adopted for enhancing the global searching ability. To improve the accuracy of the surrogate model without using extensive samples, a small number of samples are first used. Then an optimal point-adding process is carried out to reduce computational cost. Numerical studies of a cantilever plate with an internal crack are performed. The effectiveness and efficiency of this method are demonstrated by the identified results. The effect of initial sampling size on the precision of the identified results is also investigated.
Prediction of Sound Transmission Loss for Finite Sandwich Panels Based on a Test Procedure on Beam Elements
Authors: Qian Zhongchang , Chang Daoqing , Liu Bilong , Liu Ke
Published: June 2013

An approach on the prediction of sound transmission loss for a finite sandwich panel with honeycomb core is described in the paper. The sandwich panel is treated as orthotropic and the apparent bending stiffness in two principal directions is estimated by means of simple tests on beam elements cut from the sandwich panel. Utilizing orthotropic panel theory, together with the obtained bending stiffness in two directions, the sound transmission loss of simply-supported sandwich panel is predicted by the modal expansion method. Simulation results indicated that dimension, orthotropy, and loss factor may play important roles on sound transmission loss of sandwich panel. The predicted transmission loss is compared with measured data and the agreement is reasonable. This approach may provide an efficient tool to predict the sound transmission loss of finite sandwich panels.
Single Degree of Freedom Shear-Mode Piezoelectric Energy Harvester
Authors: Aladwani A. , Aldraihem O. , Baz A.
Published: June 2013

An energy harvester operating in the thickness-mode (TMH) or longitudinal-mode (LMH) consists of a piezoelectric element which is sandwiched between a proof mass and a base. The piezo-element is poled along a direction perpendicular to the electrodes. When the base is subjected to a sinusoidal excitation, along the poling direction, a relative motion is generated between the proof mass and the base producing mechanical strain in the piezoelectric element. The resulting strain is converted into electrical power by virtue of the direct piezoelectric effect. In this study, a shear-mode harvester (SMH) is considered as a viable alternative to the TMH and LMH to enhance the harvested output power. The enhancement is generated by capitalizing on the fact that the strain constant of the piezoelectric in shear is much higher than those due to thickness or longitudinal deflections. To achieve such an enhancement, the piezoelectric element is poled along a direction parallel to its electrodes and is sandwiched between a proof mass and oscillating base in a design similar to that of the TMH and the LMH. Sinusoidal excitation of the base, along the poling direction, makes the piezo-element experience mechanical shear strain which when converted into electrical power produces outputs that are larger than those of the TMH and the LMH. The theory governing the operation of this class of SMH is developed for simple resistive electrical loads. Numerical examples are presented to illustrate the optimal performance characteristics of the SMH in comparison with the TMH and LMH. The effect of the piezo-element material, excitation frequency and electrical load on the harvested power is presented. The obtained results demonstrate the feasibility of the SMH as a simple and effective means for enhancing the power output characteristics of conventional TMH and LMH.
Transverse Vibrations and Stability of Axially Traveling Sandwich Beam With Soft Core
Authors: Yang Xiao-Dong , Zhang Wei , Chen Li-Qun
Published: June 2013

The transverse vibrations and stability of an axially moving sandwich beam are studied in this investigation. The face layers are assumed to be in the membrane state, which bears only axial loading but no bending. Only shear deformation is considered for the soft core layer. The governing partial equation is derived using Newton's second law and then transferred into a dimensionless form. The Galerkin method and the complex mode method are employed to study the natural frequencies. In comparison with the classical homogenous axially moving beam, the gyroscopic matrix is no longer skew-symmetric because of the introduction of the soft core. The critical speed for the divergence of the axially moving sandwich beam is analytically obtained. The contribution of the core layer shear modulus to the natural frequencies and critical speed is discussed.
Exact Solutions for Free Vibrations and Buckling of Double Tapered Columns With Elastic Foundation and Tip Mass
Authors: Firouz-Abadi R. D. , Rahmanian M. , Amabili M.
Published: June 2013

The present study aims at the free vibration analysis of double tapered columns. Foundation is assumed to be elastic and the effects of self-weight and tip mass with significant moment of inertia are considered. The governing equation of motion is obtained using the Hamilton principle, based on both the Euler–Bernoulli and Timoshenko beam models. Applying the power series method of Frobenius, the base solutions of the governing equations are obtained in the form of a power series via general recursive relations. Applying the boundary conditions, the natural frequencies of the beam/column are obtained using both models. The obtained results are compared with literature and a very good agreement is achieved. Subsequently, comprehensive studies are performed to provide an insight into the variation of the natural frequencies and instability conditions of the beam with respect to the tip mass, self-weight, taper ratio, slenderness, and foundation stiffness and eventually some general conclusions are drawn.
Natural Frequency Clusters in Planetary Gear Vibration
Authors: Ericson Tristan M. , Parker Robert G.
Published: June 2013

This paper investigates how the natural frequencies of planetary gears tend to gather into clusters (or groups). This behavior is observed experimentally and analyzed in further detail by numerical analysis. There are three natural frequency clusters at relatively high frequencies. The modes at these natural frequencies are marked by planet gear motion and contain strain energy in the tooth meshes and planet bearings. Each cluster contains one rotational, one translational, and one planet mode type discussed in previous research. The clustering phenomenon is robust, continuing through parameter variations of several orders of magnitude. The natural frequency clusters move together as a group when planet parameters change. They never intersect, but when the natural frequencies clusters approach each other, they exchange modal properties and veer away. When central member parameters are varied, the clusters remain nearly constant except for regions in which natural frequencies simultaneously shift to different cluster groups. There are two conditions that disrupt the clustering effect or diminish its prominence. One is when the planet parameters are similar to those of the other components, and the other is when there are large differences in mass, moment of inertia, bearing stiffness, or mesh stiffness among the planet gears. The clusters remain grouped together with arbitrary planet spacing.
Friction-Induced, Self-Excited Vibration of a Pantograph-Catenary System
Authors: Qian W. J. , Chen G. X. , Zhang W. H. , Ouyang H. , Zhou Z. R.
Published: June 2013

A dynamic model of a pantograph-catenary system is established. In the model, motion of the pantograph is coupled with that of the catenary by friction. Stability of the pantograph-catenary system is studied using the finite element complex eigenvalue method. Numerical results show that there is a strong propensity of self-excited vibration of the pantograph-catenary system when the friction coefficient is greater than 0.1. The dynamic transient analysis results show that the self-excited vibration of the pantograph-catenary system can affect the contact condition between the pantograph and catenary. If the amplitude of the self-excited vibration is strong enough, the contact may even get lost. Parameter sensitivity analysis shows that the coefficient of friction, static lift force, pan-head suspension spring stiffness, tension of contact wire, and the spatial location of pantograph have important influences on the friction-induced, self-excited vibration of the pantograph-catenary system. Bringing the friction coefficient below a certain level and choosing a suitable static lift force can suppress or eliminate the contact loss between the pantograph and catenary.
Wave Based Method for Free Vibration Analysis of Cylindrical Shells
With Nonuniform Stiffener Distribution
Authors: Wei Jianhui , Chen Meixia , Hou Guoxiang , Xie Kun , Deng Naiqi
Published: June 2013

Wave based method (WBM) is presented to analysis the free vibration characteristics of cylindrical shells with nonuniform stiffener distributions for arbitrary boundary conditions. The stiffeners are treated as discrete elements. The equations of motion of annular circular plate are used to describe the motion of stiffeners. Instead of expanding the dynamic field variables in terms of polynomial approximation in element based method (finite element method etc), the ring-stiffened cylindrical shell is divided into several substructures and the dynamic field variables in each substructure are expressed as wave function expansions. Boundary conditions and continuity conditions between adjacent substructures are used to form the final matrix to be solved. Natural frequencies of cylindrical shells with uniform rings spacing and eccentricity distributions for shear diaphragm-shear diaphragm boundary conditions have been calculated by WBM model which shows good agreement with the experimental results and the analytical results of other researchers. Natural frequencies of cylindrical shells with other boundary conditions have also been calculated and the results are compared with the finite element method which also shows good agreement. Effects of the nonuniform rings spacing and nonuniform eccentricity and effects of boundary conditions on the fundamental frequencies and the beam mode frequencies have been studied. Different stiffener distributions are needed to increase the fundamental frequencies and beam mode frequencies for different boundary conditions. WBM model presented in this paper can be recognized as a semianalytical and seminumerical method which is quite useful in analyzing the vibration characteristics of cylindrical shells with nonuniform rings spacing and eccentricity distributions.
Design of a Circular Clamped Plate Excited by a Voice Coil and Piezoelectric Patches Used as a Loudspeaker
Authors: Doaré Olivier , Kergourlay Gérald , Sambuc Clément
Published: June 2013

In this article, a dynamical model of the vibrations and acoustic radiation of a circular clamped plate excited by a voice coil and two annular piezoelectric patches is derived. This model is used to perform an optimization of the geometries with the objective to minimize the vibration of the plate along its second and third modes, so that the plate's radiation is equilibrated between its first and fourth eigenfrequencies. Experiments are then performed and show a good agreement with the model. Radiation of the designed system presents improvements when compared to a system when only a voice coil is used.
Optimization of Noise Transmission Through Sandwich Structures
Authors: Guerich Mohamed , Assaf Samir
Published: June 2013

An optimization methodology to increase the noise transmission loss (TL) of damped sandwich structures is presented. The prediction of the TL uses a numerical tool based on a finite element formulation for the sandwich plate coupled to a boundary element method for the acoustic medium. This tool can be used for arbitrarily shaped three-layer sandwich plates with various boundary conditions and it is well adapted to parametric and optimization studies. First, a parametric study was conducted to choose the objective function, the constraints, and the pertinent design variables to use in the optimization problem which consist in reducing the sound power transmitted by a viscoelastically damped sandwich plate. Next, by constraining the acoustical behavior of the sandwich panel, the surface mass of the sandwich structure was minimized. It is shown that a significant reduction in the transmitted sound power can be achieved by selecting the appropriate geometric configuration and damping layer material.
Stick-Slip Vibrations of Layered Structures Undergoing Large Deflection and Dry Friction at the Interface
Authors: Sedighi Hamid M. , Shirazi Kourosh H. , Naderan-Tahan Khosro
Published: June 2013

The present study focuses on the nonlinear analysis of the dynamical behavior of layered structures, including interfacial friction in the presence of the stick-slip phenomenon and large deformation. To achieve a proper outlook for the two-layer structure's behavior, it is essential to precisely realize the mechanisms of motion. Taking the dry friction into account, coupled equations of the transversal and longitudinal large vibration of two-layers are derived and nondimensionalized. Furthermore, the free and forced vibration of the aforementioned system is investigated. From the results of the numerical simulation, it is observed that there exist quasi-periodic and stick–slip chaotic motions in the system. The results demonstrate that the single mode method usually utilized may lead to incorrect conclusions and, instead, the higher order mode method should be employed. A comparative study with ANSYS is developed to verify the accuracy of the proposed approach.
Mode Coupling-Type Instability of a Beam Subjected to Coulomb Friction
Authors: Seo Yasuhiro , Yabuno Hiroshi , Kono Go
Published: June 2013

To analyze the excitation mechanism of self-excited oscillation in a beam that is in contact with a moving floor surface such as a cleaning blade, which is a beam mounted in a laser printer to clean the photoreceptor, we study a beam subjected to Coulomb friction and theoretically predict the occurrence of self-excited oscillation through mode-coupling instability. We present an extensible beam model, and derive its governing nonlinear equations by means of special Cosserat theory, which allows for the extensibility of the beam to be considered. The boundary conditions on the end of the beam are unique because the end of the beam makes contact with the moving floor surface. We used a discretized linearized governing equation and performed linear stability analysis. The results indicate that self-excited oscillation in the beam is produced due to both Coulomb friction and mode coupling of the bending and extension of the beam based on the extensibility in the axial direction.
A Mechanical Approach to the Design of Independent Modal Space Control for Vibration Suppression
Authors: Cinquemani S. , Resta F.
Published: June 2013

Many systems have, by their nature, a small damping and therefore they are potentially subjected to dangerous vibration phenomena. The aim of active vibration control is to contain this phenomenon, improve the dynamic performance of the system, and increase its fatigue strength. A way to reach this goal is to increase the system damping, preferably without changing its natural frequencies and vibration modes. In the past decades this has been achieved by developing the well-known independent modal space control (IMSC) technique. The paper describes a new approach to the synthesis of a modal controller to suppress vibrations in structures. It turns from the traditional formulation of the problem and it demonstrates how the performance of the controller can be evaluated through the analysis of the modal damping matrix of the controlled system. The ability to easily manage this information allows us to synthesize an efficient modal controller. Furthermore, it enables us to easily evaluate the stability of the control, the effects of spillover, and the consequent effectiveness in reducing vibration. Theoretical aspects are supported by experimental applications on a large flexible system.
Semiconductor surface functionalization for advances in electronics, energy conversion, and dynamic systems
Authors: Teplyakov Andrew V. , Bent Stacey F.
Published: June 2013

Semiconductors have played a tremendous role in the development of electronics since the inception of the electronics revolution more than 60 years ago. Over this period, the performance of semiconductors relied on the development of robust and reliable surface passivation and functionalization schemes. As the size of the individual components in microelectronics has decreased, the role of surface chemistry has become even more important. Moreover, in the development of fields such as sensing and energy conversion, the surface chemistry of the component semiconductor materials has often driven the functionality of devices and applications. Available functionalization chemistries take advantage of the localized and covalent nature of the semiconductor surfaces to form organic layers that can passivate the surface, assemble nanopatterns, influence subsequent deposition, or change the nature of interfacial electron transfer. Despite an established toolkit already available for semiconductor surface functionalization, new applications will require better, cheaper, faster, and more controllable ways to produce surfaces that are well-defined, responsive to external factors, ready for further treatment, and adaptable for use on unusually shaped features or on nanostructures. Two major directions are identified in the field of semiconductor surface functionalization based on the nature of the surface response required: “static” in which surface properties are modified by classical thermodynamic and kinetic control approaches and then maintain these properties following the modification, and “dynamic” in which surfaces adapt to the conditions needed and respond to the application of external stimuli. Possible opportunities within these two development pathways are presented in this article.
JADA: A graphical user interface for comprehensive internal dose assessment in nuclear medicine
Authors: Grimes Joshua , Uribe Carlos , Celler Anna
Published: June 2013

Purpose:

The main objective of this work was to design a comprehensive dosimetry package that would keep all aspects of internal dose calculation within the framework of a single software environment and that would be applicable for a variety of dose calculation approaches.

Methods:

Our MATLAB‐based graphical user interface (GUI) can be used for processing data obtained using pure planar, pure SPECT, or hybrid planar/SPECT imaging. Time‐activity data for source regions are obtained using a set of tools that allow the user to reconstruct SPECT images, load images, coregister a series of planar images, and to perform two‐dimensional and three‐dimensional image segmentation. Curve fits are applied to the acquired time‐activity data to construct time‐activity curves, which are then integrated to obtain time‐integrated activity coefficients. Subsequently, dose estimates are made using one of three methods.

Results:

Theorgan level dose calculation subGUI calculates mean organ doses that are equivalent to dose assessment performed by OLINDA/EXM. Voxelized dose calculation options, which include the voxel S value approach and Monte Carlo simulation using the EGSnrc user code DOSXYZnrc, are available within the process 3D image data subGUI.

Conclusions:

The developed internal dosimetry software package provides an assortment of tools for every step in the dose calculation process, eliminating the need for manual data transfer between programs. This saves times and minimizes user errors, while offering a versatility that can be used to efficiently perform patient‐specific internal dose calculations in a variety of clinical situations.
Estrogen Supports Urothelial Defense Mechanisms
Authors: Lüthje Petra , Brauner Hanna , Ramos Nubia L. , Övregaard Amanda , Gläser Regine , Hirschberg Angelica Lindén , Aspenström Pontus , Brauner Annelie
Published: June 2013

Estrogen supports urothelial defense against infection by increasing the expression of antimicrobial peptides and by protecting epithelial integrity.
Estrogen and Recurrent UTI: What Are the Facts?
Authors: Hannan Thomas J. , Hooton Thomas M. , Hultgren Scott J.
Published: June 2013

Estrogen therapy promotes resistance to urinary tract infections in postmenopausal women by altering urinary tract mucosal defense mechanisms.
Symptomatic hypocalcaemia secondary to PTH resistance associated with hypomagnesaemia after elective embolisation of uterine fibroid
Authors: Griffin Tomas Patrick , Murphy Michael , Coulter John , Murphy Matthew StJohn
Published: June 2013

Four weeks after elective embolisation of a symptomatic benign uterine fibroid, a lady presented to her general practitioner with facial twitching and severe lassitude. Acute hypocalcaemia was diagnosed. Further investigations demonstrated hypomagnesaemia. Parathyroid hormone (PTH) was within normal limits. Symptoms and the acute metabolic disturbance resolved with treatment by oral magnesium and calcium supplementation. While lassitude is a common symptom of postfibroid embolisation and may last for up to 6 weeks, the presentation with facial twitching alerted the clinician to a potential electrolyte or metabolic imbalance. This is a first reported case of hypomagnesaemia associated with PTH resistance leading to hypocalcaemia precipitated by alcohol particle embolisation for benign fibroid disease.
Sarcoidosis of the pancreas mimicking adenocarcinoma
Authors: Mayne Alistair Ivan William , Ahmad Jawad , Loughrey Maurice , Taylor Mark A
Published: June 2013

Primary sarcoidosis of the pancreas is extremely rare. Clinical presentation is often identical to that of pancreatic adenocarcinoma. Preoperative diagnosis of primary pancreatic sarcoidosis is always challenging. We present a 52-year-old man who developed weight loss and obstructive jaundice. Abdomino-pelvic CT scan showed a mass in the pancreatic head. After  hepatopancreaticobiliary MDT discussion, a Whipple's procedure was attempted but the mass was deemed unresectable due to invasion of the superior mesenteric vein. Upon completion of palliative chemotherapy, repeat imaging showed significant mass shrinkage. A reattempt Whipple's procedure was successfully undertaken. Histology showed changes of chronic pancreatitis and peripancreatic granulomatous inflammation with no evidence of malignancy and a diagnosis of sarcoidosis was made. Owing to the devastating nature of pancreatic adenocarcinoma, any mass in the pancreas must be thoroughly investigated before a definitive diagnosis is made.
Successful simple limbal epithelial transplantation (SLET) in lime injury-induced limbal stem cell deficiency with ocular surface granuloma
Authors: Vazirani Jayesh , Basu Sayan , Sangwan Virender
Published: June 2013

A 9-year-old boy presented with unilateral, total limbal stem cell deficiency (LSCD) complicated by the presence of a large fibro-vascular ocular surface mass lesion secondary to accidental lime injury. The pathological tissue covering the cornea was excised and simple limbal epithelial transplantation (SLET) was performed using autologous limbal tissue from the fellow eye. Histopathology of the excised ocular surface tissue revealed exuberant granulation tissue interspersed with retained calcium particles. At 6 weeks postoperatively, a focal recurrence of LSCD with symblepharon and forniceal shortening was noted superiorly. This was successfully managed by performing conjunctival autografting along with supplemental SLET. The unaided vision had improved from light perception at presentation to 20/40 at 6 months postoperatively. The fornices were deep and the corneal surface was avascular, epithelised and stable. This case demonstrates the efficacy of SLET in a child with severe ocular burns, highlighting the role of supplementary procedures customised to treat focal recurrences of LSCD.
Isolated III cranial nerve palsy: a surprising presentation of an acute on chronic subdural haematoma
Authors: Abdul Jalil Muhammad Fahmi , Tee Jin Wee , Han Tiew
Published: June 2013

Many aetiologies have been associated with isolated oculomotor nerve palsies. They are ischaemic microangiopathy, posterior communicating artery aneurysm, uncal herniation, neoplasia, traumatic and inflammatory conditions. We report the case of a patient who presented with left oculomotor cranial nerve palsy with an associated large volume left acute on chronic subdural haematoma. Coincidentally, this woman was also found to have a recent history of herpes zoster ophthalmicus.
Herpes simplex virus encephalitis involving the right thalamus
Authors: Navin Patrick , Delanty Norman , Brennan Paul , Looby Seamus
Published: June 2013

Herpes simplex virus (HSV) encephalitis is a rare but often fatal disease if left untreated. A 50-year-old woman was admitted with lethargy, confusion, dysphasia and cough. MRI brain demonstrated bilateral temporal and perisylvian hyperintense signal abnormality extending into the cingulate gyrus, typical of HSV encephalitis. However, there was also signal abnormality involving the right thalamus, indicating thalamic involvement. EEG and cerebrospinal fluid PCR confirmed HSV encephalitis. The patient was started on intravenous acyclovir resulting in marked improvement. Adequate assessment and prompt treatment of HSV encephalitis will aid in achieving adequate recovery. Radiological investigation plays a crucial role in diagnosis with typical MR features a useful aid to diagnosis. HSV encephalitis classically involves the medial temporal lobes, insula and cingulated gyri. The basal ganglia and thalami are nearly always spared. We present a very rare case of HSV encephalitis which involved the right thalamus.
THE JACOBI LAST MULTIPLIER AND ISOCHRONICITY OF LIÉNARD TYPE SYSTEMS
Authors: GUHA PARTHA , GHOSE CHOUDHURY A.
Published: June 2013

We present a brief overview of classical isochronous planar differential systems focusing mainly on the second equation of the Liénard type ẍ + f(x)ẋ2 + g(x) = 0. In view of the close relation between Jacobi's last multiplier and the Lagrangian of such a second-order ordinary differential equation, it is possible to assign a suitable potential function to this equation. Using this along with Chalykh and Veselov's result regarding the existence of only two rational potentials which can give rise to isochronous motions for planar systems, we attempt to clarify some of the previous notions and results concerning the issue of isochronous motions for this class of differential equations. In particular, we provide a justification for the Urabe criterion besides giving a derivation of the Bolotin–MacKay potential. The method as formulated here is illustrated with several well-known examples like the quadratic Loud system and the Cherkas system and does not require any computation relying only on the standard techniques familiar to most physicists.
A GRAY-BOX NEURAL NETWORK-BASED MODEL IDENTIFICATION AND FAULT ESTIMATION SCHEME FOR NONLINEAR DYNAMIC SYSTEMS
Authors: CEN ZHAOHUI , WEI JIAOLONG , JIANG RUI
Published: June 2013

A novel gray-box neural network model (GBNNM), including multi-layer perception (MLP) neural network (NN) and integrators, is proposed for a model identification and fault estimation (MIFE) scheme. With the GBNNM, both the nonlinearity and dynamics of a class of nonlinear dynamic systems can be approximated. Unlike previous NN-based model identification methods, the GBNNM directly inherits system dynamics and separately models system nonlinearities. This model corresponds well with the object system and is easy to build. The GBNNM is embedded online as a normal model reference to obtain the quantitative residual between the object system output and the GBNNM output. This residual can accurately indicate the fault offset value, so it is suitable for differing fault severities. To further estimate the fault parameters (FPs), an improved extended state observer (ESO) using the same NNs (IESONN) from the GBNNM is proposed to avoid requiring the knowledge of ESO nonlinearity. Then, the proposed MIFE scheme is applied for reaction wheels (RW) in a satellite attitude control system (SACS). The scheme using the GBNNM is compared with other NNs in the same fault scenario, and several partial loss of effect (LOE) faults with different severities are considered to validate the effectiveness of the FP estimation and its superiority.
Hydrophilic annulated dinuclear zinc(II) phthalocyanine as Type II photosensitizers for PDT: a combined experimental and (TD)-DFT investigation
Authors: Quartarolo Angelo D. , Pérusse Dimitri , Dumoulin Fabienne , Russo Nino , Sicilia Emilia
Published: June 2013

The design, synthesis and theoretical calculations of a mononuclear and its corresponding annulated dinuclear hydrophilic zinc(II) phthalocyanines (ZnPcs) are reported here, the hydrophilic substituent being 1,3-bis((2,2-dimethyl-1,3-dioxolan-4-yl)methoxy)propan-2-ol. These novel compounds have been characterized by UV-vis spectroscopy in ethanol and ethanol:water (50:50) solutions. The electronic spectra of the mononuclear derivatives retain the main spectral features of ZnPc with a strong Q-band absorbance at 678 nm in ethanol and a less intense B-band at 370 nm. The annulated dinuclear derivatives show a broad Q-band absorbance with main wavelength maxima between 600 and 720 nm. From time-dependent density functional (TDDFT) UV-vis spectra simulation performed on selected isomers, Q-band absorption maxima of the non-peripherally substituted forms are more red-shifted compared to those of peripheral forms.
COMPARISON OF ANTIMICROBIAL PROPERTIES OF NANO QUINOLONE WITH ITS MICROSCALE EFFECTS
Authors: BEHBAHANI G. REZAIE , SADR M. HOSSAINI , NABIPOUR H. , BEHBAHANI H. REZAEI , VAHEDPOUR M. , BARZEGAR L.
Published: June 2013

Nano nalidixic acid was prepared by ultrasonic method in carbon tetrachloride. Nano nalidixic acid (quinolone antibiotic) was characterized by X-ray diffraction (XRD), infrared spectroscopy (IR) and scanning electron microscope (SEM). The antibacterial activities of nano nalidixic acid were tested against microorganisms and compared with the microscale drug. The results show that nano nalidixic acid has good inhibitory properties against two Gram-positive species, Staphylococcus aureus and Bacillus subtilis. Nano nalidixic acid also showed good antifungal activity against Candida albicans. Nano nalidixic acid can be injected into the human body as a decontaminating agent to prevent the growth of harmful microorganisms more effectively than the micro-sized drug.
SIMULTANEOUS CONCENTRATION AND DETECTION OF ESCHERICHIA COLI USING CARBON NANOTUBE DEVICES
Authors: PARK DONG-WON , CHOI WON-JIN , YANG CHEOL SOO , PARK SERIN , SEO EUN MI , KIM SEUNG-SU , CHANG HYUNJU , LEE JEONG-O , KIM BEOM SOO
Published: June 2013

The performance of a nanoscale sensor is not limited by the sensitivity of the sensor itself but rather by the diffusion time required for target molecules to reach to the extremely small sensor surface. In this work, we developed a carbon nanotube device that performed the dual functions of concentrating and detecting microorganisms in a sample solution. The sensor surface area was increased by fabricating a carbon nanotube network device using thermal chemical vapor deposition and standard microfabrication techniques. The target Escherichia coli (E. coli) cells were concentrated at the sensor surface via dielectrophoretic concentration by the carbon nanotube network channels. After 10 min of collection, the chip was washed with ample amounts of a clean buffer solution, and only the E. coli cells that were bound to the antibodies remained on the sensor surface. The binding of E. coli to the CNT network device decreased the conductance, presumably due to an increase in the scattering at the sensor surface. The detection limit and the time required for microorganism detection was greatly improved by combining dielectrophoresis with the carbon nanotube devices.
EMD VIA MEMD: MULTIVARIATE NOISE-AIDED COMPUTATION OF STANDARD EMD
Authors: UR REHMAN NAVEED , PARK CHEOLSOO , HUANG NORDEN E. , MANDIC DANILO P.
Published: June 2013

A noise-assisted approach in conjunction with multivariate empirical mode decomposition (MEMD) algorithm is proposed for the computation of empirical mode decomposition (EMD), in order to produce localized frequency estimates at the accuracy level of instantaneous frequency. Despite many advantages of EMD, such as its data driven nature, a compact decomposition, and its inherent ability to process nonstationary data, it only caters for signals with a sufficient number of local extrema. In addition, EMD is prone to mode-mixing and is designed for univariate data. We show that the noise-assisted MEMD (NA-MEMD) approach, which utilizes the dyadic filter bank property of MEMD, provides a solution to the above problems when used to calculate standard EMD. The method is also shown to alleviate the effects of noise interference in univariate noise-assisted EMD algorithms which directly add noise to the data. The efficacy of the proposed method, in terms of improved frequency localization and reduced mode-mixing, is demonstrated via simulations on electroencephalogram (EEG) data sets, over two paradigms in brain-computer interface (BCI).
STIMULI RESPONSIVE MORPHOLOGICAL CHANGES OF PNIPA POLYMER BRUSHES SYNTHESIZED ON SILICON SUBSTRATE
Authors: HUDA MUHAMMAD NURUL , KABIR A. N. M. HAMIDUL
Published: June 2013

High-density polymer brushes were grown from the silicon surface by atom transfer radical polymerization of Poly(N-isopropylacrylamide) (PNIPA) at different polymerization conditions. PNIPA brushes were prepared using Copper (I) Chloride/tris(2-(dimetylamino)ethyl)amine (Me6TREN) as a catalytic system in DMSO at 20°C. Free polymer formed during the brush formation was characterized by gel permeation chromatography. The grafting densities up to 0.52 chains/nm2 were obtained. The layer thickness of polymer brush increases with the increase of conversion of the monomer conversion as well as polymerization time. Atomic force microscopy and air bubble contact angle under pH solution were employed to study the surface morphology, reversible conformational changes of and stimulus-response behavior. PNIPA brushes exhibited a different nanomorphology after treatment with different pH solution. It also revealed a unique reversible wetting behavior with pH. The reversible properties of the PNIPA brushes can be used to regulate the adsorption of the sulfonated PS nanoparticles.
Shortening, structural relief and drainage evolution in inverted rifts: insights from the Atlas Mountains, the Eastern Cordillera of Colombia and the Pyrenees
Authors: Babault Julien , Teixell Antonio , Struth Lucía , Van Den Driessche Jean , Arboleya María Luisa , Tesón Eliseo
Published: June 2013

The Atlas, Eastern Cordillera and Pyrenees are thick-skinned thrust-fold belts formed by tectonic inversion of rift basins in continental settings. A comparison of shortening between them shows a gradation from 20–25% in the central High Atlas, to 25–30% in the Eastern Cordillera, and
c.
40% in the Pyrenees. Accordingly, there is a structural variation from interior zones with low structural relief and isolated basement massifs in the first two cases, to an axial culmination of stacked basement thrust sheets in the Pyrenees. This results in marked topographic and drainage variation: the High Atlas and Eastern Cordillera contain axial plateaus dominated by structure-controlled longitudinal rivers and orogen flanks with slope-controlled transverse rivers, whereas the Pyrenees show a two-sided wedge profile dominated by transverse rivers. In spite of singularities exhibited by each orogen, we propose that this spatial variation can be understood as reflecting different degrees of evolution in mountain building. Rapidly incising, transverse rivers are capturing earlier longitudinal streams of the Atlas and Eastern Cordillera, thus reducing their axial plateaux, which will eventually disappear into a transverse-dominated drainage. This pattern of landscape evolution may be characteristic of inversion orogens as they develop from initial stages of inversion to full accretion.