bluuebunny/crossref_metadata_2025 huggingface dataset:
Performance Investigation of the Hybrid-Renewable Energy System With Geothermal and Solar Heat Sources for a Residential Building in South Korea
Authors: Woo Nam-Sub , Kim Young-Ju , Jo Young-Do , Hwang In-Ju
Published: November 2012

This study investigates annual performance of the hybrid energy system with geothermal and solar heat sources for hot water, heating and cooling of a residential house in South Korea. A small-scale hybrid-renewable energy system (H-RES) consists of a geothermal heat pump for heating and cooling, solar collectors for hot water, a gas fired backup boiler, and incidental facilities. All pipelines are designed for heat flow between the modules such as storage tank, heat production units, and radiators. Also, all systems automatically operated by the integrated sensing and control system. The average coefficient of performance of geothermal module during cooling and heating seasons is evaluated as about 4.1 and 3.5, respectively. Solar fraction for hot water is calculated as over 54%. And annual energy consumption of the H-RES is estimated as much as about 40% of conventional energy systems.
Three Cooling Seasons Monitoring of Exergetic Performance Analysis of an EAHE Assisted Solar Greenhouse Building
Authors: Ozgener Onder , Ozgener Leyla
Published: November 2012

The present manuscript experimentally investigated the exergetic performance (efficiency) of a closed loop earth to air heat exchanger (underground air tunnel) in the cooling mode. The experimental system was commissioned in June 2009 and experimental data collecting have been conducted since then. The data, consisting of hourly thermodynamics records a year cooling period, 2009–2011, were measured in the Solar Energy Institute of the Bornova Campus at Ege University. At the present time, the database contains more than 40,000 records of measurements. Exergetic efficiencies value of the system and system components have been analyzed. Furthermore, a long term exergetic modeling of a closed loop earth-to-air heat exchanger solar greenhouse cooling system for system analysis and performance assessment is presented. Exergetic efficiency of the system and its compenents at various reference states are also determined.
Monitoring Array Output Current and Voltage in Stand Alone Photovoltaics Systems With Pulse Width Modulated Charge Regulators
Authors: Muñoz F. J. , Torres M. , Muñoz J. V. , Fuentes M.
Published: November 2012

Pulse width modulated (PWM) charge regulators are frequently used in stand alone photovoltaic (SAPV) systems. Once the battery has reached the regulating voltage, these electronic devices provide current and voltage pulses to regulate the charge current to the battery. This kind of signals implies rapid variation in the variables and may provide, when being monitored, and if some special considerations are not taken into account, an erroneous measurement of the array output current, the array output voltage and the current to storage. Moreover, this inappropriate monitoring will affect not only to these monitored variables but also may spread over the array output power and most of the derived parameters, providing a mistaken system performance analysis from monitored data. In this way, this paper focus on the different issues that can arise when monitoring the parameters mentioned above in SAPV systems with PWM charge regulators. A comparative study of the two types of sensors (shunt and hall-effect transducer) that can be used to capture either the array output current or the current to storage will be developed. Moreover, it is intended to provide easy monitoring procedures to collect the array output and voltage, the current to storage and the array output power as these variables are the more sensitive to the use of PWM charge regulators. These monitoring requirements may be appropriate under field conditions and may become cost-effective. The solutions given here intends to avoid the complex monitoring system and the high computational cost that may require a simultaneous sampling mode at a relative high sampling frequency to obtain an appropriate monitoring for the modulated signals in SAPV systems with PWM charge regulators.
Double-Young Tristable Mechanisms
Authors: Chen Guimin , Du Yunlei
Published: November 2012

In this work, we present a new class of tristable mechanism called double Young tristable mechanisms (DYTMs), which connect two prestrained Young bistable mechanisms to create three distinct stable equilibrium positions. A three-degree-of-freedom pseudorigid-body (RPB) model is proposed to accurately predict the kinetostatic behaviors of both Young mechanisms and DYTMs. An optimization-based design method is also presented for DYTMs. Two DYTM prototypes were designed based on the method and machined out of polypropylene sheets. Both of the prototypes exhibit tristability, which demonstrate the feasibility of achieving tristability through connecting two prestrained Young mechanisms. The successful prototyping also indicates that the proposed three degree-of-freedom (3DOF) model is capable of identifying feasible designs for DYTMs.
The Importance of Intrinsic Damage Properties to Bone Fragility: A Finite Element Study
Authors: Hardisty M. R. , Zauel R. , Stover S. M. , Fyhrie D. P.
Published: November 2012

As the average age of the population has increased, the incidence of age-related bone fracture has also increased. While some of the increase of fracture incidence with age is related to loss of bone mass, a significant part of the risk is unexplained and may be caused by changes in intrinsic material properties of the hard tissue. This investigation focused on understanding how changes to the intrinsic damage properties affect bone fragility. We hypothesized that the intrinsic (μm) damage properties of bone tissue strongly and nonlinearly affect mechanical behavior at the apparent (whole tissue, cm) level. The importance of intrinsic properties on the apparent level behavior of trabecular bone tissue was investigated using voxel based finite element analysis. Trabecular bone cores from human T12 vertebrae were scanned using microcomputed tomography (μCT) and the images used to build nonlinear finite element models. Isotropic and initially homogenous material properties were used for all elements. The elastic modulus (Ei) of individual elements was reduced with a secant damage rule relating only principal tensile tissue strain to modulus damage. Apparent level resistance to fracture as a function of changes in the intrinsic damage properties was measured using the mechanical energy to failure per unit volume (apparent toughness modulus, Wa) and the apparent yield strength (σay, calculated using the 0.2% offset). Intrinsic damage properties had a profound nonlinear effect on the apparent tissue level mechanical response. Intrinsic level failure occurs prior to apparent yield strength (σay). Apparent yield strength (σay) and toughness vary strongly (1200% and 400%, respectively) with relatively small changes in the intrinsic damage behavior. The range of apparent maximum stresses predicted by the models was consistent with those measured experimentally for these trabecular bone cores from the experimental axial compressive loading (experimental: σmax = 3.0–4.3 MPa; modeling: σmax = 2–16 MPa). This finding differs significantly from previous studies based on nondamaging intrinsic material models. Further observations were that this intrinsic damage model reproduced important experimental apparent level behaviors including softening after peak load, microdamage accumulation before apparent yield (0.2% offset), unload softening, and sensitivity of the apparent level mechanical properties to variability of the intrinsic properties.
Hyperbolic Source Location of Crack Related Acoustic Emission in Bone
Authors: O'Toole John , Creedon Leo , Hession John , Muir Gordon
Published: November 2012

Little work has been done on the localization of microcracks in bone using acoustic emission. Microcrack localization is useful to study the fracture process in bone and to prevent fractures in patients. Locating microcracks that occur before fracture allows one to predict where fracture will occur if continued stress is applied to the bone. Two source location algorithms were developed to locate microcracks on rectangular bovine bone samples. The first algorithm uses a constant velocity approach which has some difficulty dealing with the anisotropic nature of bone. However, the second algorithm uses an iterative technique to estimate the correct velocity for the acoustic emission source location being located. In tests with simulated microcracks, the constant velocity algorithm achieves a median error of 1.78 mm (IQR 1.51 mm) and the variable velocity algorithm improves this to a median error of 0.70 mm (IQR 0.79 mm). An experiment in which the bone samples were loaded in a three point bend test until they fractured showed a good correlation between the computed location of detected microcracks and where the final fracture occurred. Microcracks can be located on bovine bone samples using acoustic emission with good accuracy and precision.
Murray's Law in Elastin Haploinsufficient (Eln+/−) and Wild-Type (WT) Mice
Authors: Sather Bradley A. , Hageman Daniel , Wagenseil Jessica E.
Published: November 2012

Using either the principle of minimum energy or constant shear stress, a relation can be derived that predicts the diameters of branching vessels at a bifurcation. This relation, known as Murray's Law, has been shown to predict vessel diameters in a variety of cardiovascular systems from adult humans to developing chicks. The goal of this study is to investigate Murray's Law in vessels from mice that are haploinsufficient for the elastin protein (Eln+/−). Elastin is one of the major proteins in the blood vessel wall and is organized in concentric rings, known as lamellae, with smooth muscle cells (SMCs) around the vessel lumen. Eln+/− mice have an increased number of lamellae, as well as smaller, thinner vessels. It is possible that due to decreased amounts of elastin available for vessel wall remodeling during development and in adulthood, Eln+/− vessels would not follow Murray's Law. We examined vessel bifurcations in six different physiologic regions, including the brain, heart, epidermis, ceocum (or cecum), testes, and intestines, in Eln+/− mice and wild-type (WT) littermates. All vessels were between 40 and 300 μm in diameter. We found that the diameters of both Eln+/− and WT vessels have an average of 13% error from the diameters predicted by Murray's Law, with no significant differences between genotypes or physiologic regions. The data suggest that vessels are optimized to follow Murray's Law, despite limitations on the proteins available for growth and remodeling of the vessel wall.
On the Importance of Modeling Stent Procedure for Predicting Arterial Mechanics
Authors: Zhao Shijia , Gu Linxia , Froemming Stacey R.
Published: November 2012

The stent-artery interactions have been increasingly studied using the finite element method for better understanding of the biomechanical environment changes on the artery and its implications. However, the deployment of balloon-expandable stents was generally simplified without considering the balloon-stent interactions, the initial crimping process of the stent, its overexpansion routinely used in the clinical practice, or its recoil process. In this work, the stenting procedure was mimicked by incorporating all the above-mentioned simplifications. The impact of various simplifications on the stent-induced arterial stresses was systematically investigated. The plastic strain history of stent and its resulted geometrical variations, as well as arterial mechanics were quantified and compared. Results showed the model without considering the stent crimping process underestimating the minimum stent diameter by 17.2%, and overestimating the maximum radial recoil by 144%. It was also suggested that overexpansion resulted in a larger stent diameter, but a greater radial recoil ratio and larger intimal area with high stress were also obtained along with the increase in degree of overexpansion.
Analysis of Discrete Mechanical Systems With Blockable Directions
Authors: Yunt Kerim
Published: November 2012

The classification of constraints in mechanics and the various mechanical principles that apply to different types of constraints constitute a major area of research in the field of theoretical and applied mechanics. The sudden introduction of bilateral constraints into a mechanical process is blocking and its sudden removal is releasing. The sudden introduction and removal of bilateral constraints, which exist in a subset of the whole process time span, may induce impacts. An impulsive action integral is proposed for such mechanical processes. The projectors of the tangent space of the submanifold and the cotangent space are derived and the equations of motion in different constrained submanifolds are obtained by making use of the projectors. The questions of the uniqueness and the existence of the post-transition velocity are addressed.
Numerical Investigation of Adhesive Wear and Static Friction Based on the Ductile Fracture of Junction
Authors: Wu Aizhong , Shi Xi
Published: November 2012

Adhesion plays a significant role in the friction and wear in the case where the contact surfaces are continuous and smooth such that roughness-based factors are negligible. Therefore, imposing an external load to overcome the friction is, in essence, a failure process of adhesive junctions. In this work, a finite element model was developed in order to investigate the formation of adhesive wear particles and static friction based on the ductile fracture of junctions. Focusing on the cylindrical contact and the combined contact loading configuration, a modified element deletion method with three empiric fracture criteria was employed and the failed elements satisfying some fracture criterion were used to represent the cracks. Based on the different crack development stages, a qualitative adhesive wear mechanism was summarized. The simulation results indicate that the secondary crack initiated in the pile-up of material possibly accounts for the crack kinking, which is the origin of the flake-like wear particle. Friction behaviors under different loading configurations were investigated and a simple comparison for three different fracture models was presented. It was found that all three models show the same trend of friction decreasing with the increase of normal preload. Where the most conservative Bao–Wierzibicki (BW) fracture model predicts higher friction compared to two other fracture models, the Johnson–Cook (JC) model predicts a lower ductile fracture strain, thus the ductility of the material is relatively underestimated.
Observation of super‐resolution in digital breast tomosynthesis
Authors: Acciavatti Raymond J. , Maidment Andrew D. A.
Published: November 2012

Purpose:

Digital breast tomosynthesis (DBT) is a 3D x‐ray imaging modality in which tomographic sections of the breast are generated from a limited range of tube angles. Because oblique x‐ray incidence shifts the image of an object in subpixel detector element increments with each increasing projection angle, it is demonstrated that DBT is capable of super‐resolution (i.e., subpixel resolution).

Methods:

By convention, DBT reconstructions are performed on planes parallel to the breast support at various depths of the breast volume. In order for resolution in each reconstructed slice to be comparable to the detector, the pixel size should match that of the detector elements; hence, the highest frequency that can be resolved in the plane of reconstruction is the alias frequency of the detector. This study considers reconstruction grids with much smaller pixelation to visualize higher frequencies. For analytical proof of super‐resolution, a theoretical framework is developed in which the reconstruction of a high frequency sinusoidal input is calculated using both simple backprojection (SBP) and filtered backprojection. To study the frequency spectrum of the reconstruction, its Fourier transform is also determined. The experimental feasibility of super‐resolution was investigated by acquiring images of a bar pattern phantom with frequencies higher than the detector alias frequency.

Results:

Using analytical modeling, it is shown that the central projection cannot resolve frequencies exceeding the detector alias frequency. The Fourier transform of the central projection is maximized at a lower frequency than the input as evidence of aliasing. By contrast, SBP reconstruction can resolve the input, and its Fourier transform is correctly maximized at the input frequency. Incorporating filters into the reconstruction smoothens pixelation artifacts in the spatial domain and reduces spectral leakage in the Fourier domain. It is also demonstrated that the existence of super‐resolution is dependent on position in the reconstruction and on the directionality of the input frequency. Consistent with the analytical results, experimental reconstructions of bar patterns showed visibility of frequencies greater than the detector alias frequency. Super‐resolution was present at positions predicted from analytical modeling.

Conclusions:

This work demonstrates the existence of super‐resolution in DBT. Super‐resolution has the potential to impact the visualization of fine structural details in the breast, such as microcalcifications and other subtle signs of cancer.
Intraoperative patient registration using volumetric true 3D ultrasound without fiducials
Authors: Ji Songbai , Roberts David W. , Hartov Alex , Paulsen Keith D.
Published: November 2012

Purpose:

Accurate patient registration is crucial for effective image‐guidance in open cranial surgery. Typically, it is accomplished by matching skin‐affixed fiducials manually identified in the operating room (OR) with their counterparts in the preoperative images, which not only consumes OR time and personnel resources but also relies on the presence (and subsequent fixation) of the fiducials during the preoperative scans (until the procedure begins). In this study, the authors present a completely automatic, volumetric image‐based patient registration technique that does not rely on fiducials by registering tracked (true) 3D ultrasound (3DUS) directly with preoperative magnetic resonance (MR) images.

Methods:

Multistart registrations between binary 3DUS and MR volumes were first executed to generate an initial starting point without incorporating prior information on the US transducer contact point location or orientation for subsequent registration between grayscale 3DUS and MR via maximization of either mutual information (MI) or correlation ratio (CR). Patient registration was then computed through concatenation of spatial transformations.

Results:

In ten (N = 10) patient cases, an average fiducial (marker) distance error (FDE) of 5.0 mm and 4.3 mm was achieved using MI or CR registration (FDE was smaller with CR vs MI in eight of ten cases), which are comparable to values reported for typical fiducial‐ or surface‐based patient registrations. The translational and rotational capture ranges were found to be 24.0 mm and 27.0° for binary registrations (up to 32.8 mm and 36.4°), 12.2 mm and 25.6° for MI registrations (up to 18.3 mm and 34.4°), and 22.6 mm and 40.8° for CR registrations (up to 48.5 mm and 65.6°), respectively. The execution time to complete a patient registration was 12–15 min with parallel processing, which can be significantly reduced by confining the 3DUS transducer location to the center of craniotomy in MR before registration (an execution time of 5 min is achievable).

Conclusions:

Because common features deep in the brain and throughout the surgical volume of interest are used, intraoperative fiducial‐less patient registration is possible on‐demand, which is attractive in cases where preoperative patient registration is compromised (e.g., from loss/movement of skin‐affixed fiducials) or not possible (e.g., in cases of emergency when external fiducials were not placed in time). CR registration was more robust than MI (capture range about twice as big) and appears to be more accurate, although both methods are comparable to or better than fiducial‐based registration in the patient cases evaluated. The results presented here suggest that 3DUS image‐based patient registration holds promise for clinical application in the future.
Treating Diabetes and Obesity with an FGF21-Mimetic Antibody Activating the βKlotho/FGFR1c Receptor Complex
Authors: Foltz Ian N. , Hu Sylvia , King Chadwick , Wu Xinle , Yang Chaofeng , Wang Wei , Weiszmann Jennifer , Stevens Jennitte , Chen Jiyun Sunny , Nuanmanee Noi , Gupte Jamila , Komorowski Renee , Sekirov Laura , Hager Todd , Arora Taruna , Ge Hongfei , Baribault Helene , Wang Fen , Sheng Jackie , Karow Margaret , Wang Minghan , Luo Yongde , McKeehan Wallace , Wang Zhulun , Véniant Murielle M. , Li Yang
Published: November 2012

A monoclonal antibody mimic of FGF21 exerts beneficial metabolic effects in obese monkeys.
Detection of Chromosomal Alterations in the Circulation of Cancer Patients with Whole-Genome Sequencing
Authors: Leary Rebecca J. , Sausen Mark , Kinde Isaac , Papadopoulos Nickolas , Carpten John D. , Craig David , O’Shaughnessy Joyce , Kinzler Kenneth W. , Parmigiani Giovanni , Vogelstein Bert , Diaz Luis A. , Velculescu Victor E.
Published: November 2012

Massively parallel sequencing directly detects tumor-derived chromosomal alterations in plasma DNA from cancer patients.
A Shot in the Arm for ART
Authors: Barnabas Ruanne V.
Published: November 2012

Boosting the immune system of HIV patients with IFN-α suppresses HIV replication.
Genome Sequence of the Thermotolerant Yeast Kluyveromyces marxianus var.
marxianus
KCTC 17555
Authors: Jeong Haeyoung , Lee Dae-Hee , Kim Sun Hong , Kim Hyun-Jin , Lee Kyusang , Song Ju Yeon , Kim Byung Kwon , Sung Bong Hyun , Park Jae Chan , Sohn Jung Hoon , Koo Hyun Min , Kim Jihyun F.
Published: November 2012

Kluyveromyces marxianus
is a thermotolerant yeast that has been explored for potential use in biotechnological applications, such as production of biofuels, single-cell proteins, enzymes, and other heterologous proteins. Here, we present the high-quality draft of the 10.9-Mb genome of
K. marxianus
var.
marxianu
s KCTC 17555 (= CBS 6556 = ATCC 26548).
Horizontal Transfer of Antibiotic Resistance Genes on Abiotic Touch Surfaces: Implications for Public Health
Authors: Warnes Sarah L. , Highmore Callum J. , Keevil C. William
Published: November 2012

Horizontal gene transfer (HGT) is largely responsible for increasing the incidence of antibiotic-resistant infections worldwide. While studies have focused on HGT
in vivo
, this work investigates whether the ability of pathogens to persist in the environment, particularly on touch surfaces, may also play an important role.
Escherichia coli
, virulent clone ST131, and
Klebsiella pneumoniae
harboring extended-spectrum-β-lactamase (ESBL)
bla
CTX-M-15
and metallo-β-lactamase
bla
NDM-1
, respectively, exhibited prolonged survival on stainless steel, with approximately 10
4
viable cells remaining from an inoculum of 10
7
 CFU per cm
2
after 1 month at 21°C. HGT of
bla
to an antibiotic-sensitive but azide-resistant recipient
E. coli
strain occurred on stainless steel dry touch surfaces and in suspension but not on dry copper. The conjugation frequency was approximately 10 to 50 times greater and occurred immediately, and resulting transconjugants were more stable with ESBL
E. coli
as the donor cell than with
K. pneumoniae
, but
bla
NDM-1
transfer increased with time. Transconjugants also exhibited the same resistance profile as the donor, suggesting multiple gene transfer. Rapid death, inhibition of respiration, and destruction of genomic and plasmid DNA of both pathogens occurred on copper alloys accompanied by a reduction in
bla
copy number. Naked
E. coli
DNA degraded on copper at 21°C and 37°C but slowly at 4°C, suggesting a direct role for the metal. Persistence of viable pathogenic bacteria on touch surfaces may not only increase the risk of infection transmission but may also contribute to the spread of antibiotic resistance by HGT. The use of copper alloys as antimicrobial touch surfaces may help reduce infection and HGT.

IMPORTANCE
Horizontal gene transfer (HGT) conferring resistance to many classes of antimicrobials has resulted in a worldwide epidemic of nosocomial and community infections caused by multidrug-resistant microorganisms, leading to suggestions that we are in effect returning to the preantibiotic era. While studies have focused on HGT
in vivo
, this work investigates whether the ability of pathogens to persist in the environment, particularly on touch surfaces, may also play an important role. Here we show prolonged (several-week) survival of multidrug-resistant
Escherichia coli
and
Klebsiella pneumoniae
on stainless steel surfaces. Plasmid-mediated HGT of β-lactamase genes to an azide-resistant recipient
E. coli
strain occurred when the donor and recipient cells were mixed together on stainless steel and in suspension but not on copper surfaces. In addition, rapid death of both antibiotic-resistant strains and destruction of plasmid and genomic DNA were observed on copper and copper alloy surfaces, which could be useful in the prevention of infection spread and gene transfer.
Transhepatic embolisation of a traumatic broncho-biliary fistula: a novel approach
Authors: Mehrzad Homoyoon , Aziz Akhmid , Mangat Kamarjit
Published: November 2012

Bronchobiliary fistula is a rare and challenging condition that most commonly presents worldwide following infection with hydatid cystic disease of the liver but is increasingly seen in cases of trauma involving the right upper quadrant. The most common presenting complaint is biliptysis. Treatment is initially aimed at decompressing the biliary tree which allows a considered approach for closure of the fistulous tract. Options range from conservative management to endoscopic and percutaneous approaches. Traditionally definitive treatment would have been surgical and may ultimately have resulted in hepatic and/or pulmonary segmentectomy. Current management strategies of this potentially serious condition are variable. We describe a particularly challenging case in which interventional embolisation with microcoils was used in an attempt to treat persistent post-traumatic bronchobiliary fistula in a tertiary centre. We describe this technique and hope that it is may be of useful reference for those contemplating a similar approach.
How the simplest dental implant procedure can trigger an extremely serious complication
Authors: Felisati Giovanni , Saibene Alberto Maria , Di Pasquale Daniele , Borloni Roberto
Published: November 2012

A 62-year-old man came to our attention after an operation in a small dental outpatient clinic where only a single dentist was working. The man was showing complications after insertion of a dental implant in the anterior segments of the mandible. Bleeding led to a slow swelling of the neck with airway obstruction. Only an immediate intervention by a mobile emergency unit and prompt tracheal intubation avoided death by asphyxia. The patient was then transferred to our hospital. We inspected the patient and we performed a CT scan that showed complete airway obstruction. First, we performed a tracheotomy in order to ensure the airway patency and then we identified the source of bleeding: the mylohyoid artery placed anomalously close to the mandible. After clamping and tying the artery, the bleeding resolved. One day after the procedure, the tracheotomy was closed; the patient was discharged after 3 days.
Ruptured heterotopic pregnancy: an unusual presentation of an uncommon clinical problem
Authors: Gibson Kyle R , Horne Andrew W
Published: November 2012

A 30-year-old nulliparous lady presented to our Emergency Gynaecology Service with a 3-day history of epigastric pain and vomiting at 7 weeks of gestation. An intrauterine pregnancy had been confirmed 3 days earlier when she had attended with an episode of left-iliac fossa pain. Unfortunately, she became more unwell within 1 h of admission and as the cause of her symptoms was unclear, she was taken to the theatre for a joint gynaecology and general surgical diagnostic laparoscopy. This revealed a haemoperitoneum of 2 litres and a ruptured ectopic pregnancy in her left fallopian tube. A left salpingectomy was undertaken to remove the ectopic pregnancy. The patient made an excellent recovery and delivered a healthy baby at 39 weeks of gestation without further complication.
A rare manifestation of sarcoidosis with sensomotoric neuropathy of the ulnar nerve as the only symptom
Authors: Mattiassich Georg , Schubert Heinrich , Hutarew Georg , Wechselberger Gottfried
Published: November 2012

A 79-year-old woman was admitted complaining of progressive weakness and numbness of the right hand. The patient was otherwise healthy. The patient's history was unremarkable. Clinical and electrophysiological examination revealed a compression of the ulnar nerve in the ulnar sulcus and in Guyon's canal. Ultrasound evaluation showed a suspicious tumour proximal to the elbow close to the ulnar nerve. The ulnar sulcus was then released and an epineural and perineural lesion 3–4 cm proximal to the sulcus was excised under microscope. The histopathology confirmed the lesion as non-caseating sarcoid granulomas. The patient showed no other signs of systemic sarcoidosis, as neuropathy was the only symptom and the condition improved postoperatively. Sensory deficits and paraesthesia resolved fully. The extension of the minor finger remained slightly inferior compared with the not affected side. Sarcoid neuropathy is a rare neurological complication of sarcoidosis and has to be included in differential diagnosis of nerve conduction impairments.
Paediatric choroidal osteoma treated with ranibizumab
Authors: Vayalambrone Deepak , Misra Aseema
Published: November 2012

An 11-year-old patient presented with blurred vision in both eyes resulting from bilateral choroidal osteoma. The patient was treated with a course of monthly intravitreal injections of ranibizumab for 3 months and this led to improvement of visual acuity. This effect was sustained without the need for further injections over a 2-year period of follow-up.
The importance of an ECG: back to basics
Authors: Haidari Golaleh , Gray Kirsty , Kirubakaran Senthil
Published: November 2012

A 48-year-old man presented to accident and emergency with syncope on a background history of 3 weeks of increasing shortness of breath. He collapsed at home prompting admission. He was a smoker with a 30-pack-year history. On examination, he was found to be tachypnoeic and hypoxic, with a raised JVP and quiet heard sounds. He was haemodynamically stable and a chest x-ray showed right upper-lobe collapse.

His resting ECG demonstrated electrical alternans prompting urgent referral to the cardiologist for echocardiography. This revealed a large pericardial effusion with evidence of right ventricular diastolic collapse. In view of this, he underwent urgent pericardiocentesis.

A subsequent CT scan showed bilateral pleural effusions and multiple lung nodules. Both pericardial and pleural fluid cytology were reported as metastatic non-small cell adenocarcinoma. The pericardial fluid continued to reaccumulate requiring a pericardial window. He was referred to the oncology team for palliative chemotherapy.
Acute brachial neuritis following influenza vaccination
Authors: Shaikh Maliha Farhana , Baqai Tanya Jane , Tahir Hasan
Published: November 2012

Brachial neuritis following vaccination is an uncommon but clinically important presentation of severe shoulder and arm pain associated with globally reduced range of movement. It may be confused with the more common diagnoses of rotator cuff pathology, adhesive capsulitis (frozen shoulder), shoulder arthritis or cervical spondylosis. We present a case of acute brachial neuritis, which posed a clinical diagnostic challenge to emergency, acute medical and rheumatology clinicians.
Mansonella ozzardicorneal lesions in the Amazon: a cross-sectional study
Authors: Vianna Lucas Monferrari Monteiro , Martins Marilaine , Cohen Marcos Jacob , Cohen Jacob Moyses , Belfort Rubens
Published: November 2012

Objectives

To characterise and confirm the presence ofMansonella ozzardimicrofilariae in the cornea by biomicroscopy and corneal confocal microscopy.

Design

Cross-sectional study.

Settings

Clinical practice study in patients from rural communities in Coari city on the Solimões river, Amazonas state, Brazil.

Participants

The eyes of 212 consecutive volunteer patients were examined using a flash light and their blood checked for the presence of microfilariae by an expert microscopist. Patients with suspicious corneal lesions (characterised as nummular keratitis) were submitted to biomicroscopy, fundoscopy and corneal confocal microscopy evaluation (CCME). In two patients, a biopsy of the limbal conjunctiva adjacent to the nummular keratitis was carried out and blood collected from the surgical wound for microfilariae investigation by thick blood film examination.

Primary and secondary outcome measures

Positive correlation between corneal biomicroscopic and confocal lesions andM ozzardimicrofilaremia.

Results

Of the 212 patients, 56 (26.4%) were positive for microfilaremia. 22 patients with nummular keratitis identified under flash light examination underwent biomicroscopy and CCME. Corneal lesions were positively correlated to microfilaremia (p=0.0001). At biomicroscopy, lesions were classified as quiescent or active. At CCME, lesions were categorised as circular or filiform. The associations between corneal lesions, CCME findings and microfilaremia are shown.

Conclusions

We describeM ozzardimicrofilariae in the cornea and the associated eye pathology. Further studies using ocular tissue PCR and other imaging techniques would be helpful.
Science without meritocracy. Discrimination among European specialists in infectious diseases and clinical microbiology: a questionnaire survey
Authors: Tacconelli Evelina , Poljak Mario , Cacace Marina , Caiati Giovanni , Benzonana Nur , Nagy Elisabeth , Kortbeek Titia
Published: November 2012

Objective

In 2009, in a European survey, around a quarter of Europeans reported witnessing discrimination or harassment at their workplace. The parity committee from the European Society of Clinical Microbiology and Infectious Diseases (ESCMID) designed a questionnaire survey to investigate forms of discrimination with respect to country, gender and ethnicity among medical professionals in hospitals and universities carrying out activities in the clinical microbiology (CM) and infectious diseases (ID) fields.

Design

The survey consisted of 61 questions divided into five areas (sociodemographic, professional census and environment, leadership and generic) and ran anonymously for nearly 3 months on the ESCMID website.

Subjects

European specialists in CM/ID.

Results

Overall, we included 1274 professionals. The majority of respondents (68%) stated that discrimination is present in medical science. A quarter of them reported personal experience with discrimination, mainly associated with gender and geographic region. Specialists from South-Western Europe experienced events at a much higher rate (37%) than other European regions. The proportion of women among full professor was on average 46% in CM and 26% in ID. Participation in high-level decision-making committees was significantly (>10 percentage points) different by gender and geographic origin. Yearly gross salary among CM/ID professionals was significantly different among European countries and by gender, within the same country. More than one-third of respondents (38%) stated that international societies in CM/ID have an imbalance as for committee member distribution and speakers at international conferences.

Conclusions

A quarter of CM/ID specialists experienced career and research discrimination in European hospitals and universities, mainly related to gender and geographic origin. Implementing proactive policies to tackle discrimination and improve representativeness and balance in career among CM/ID professionals in Europe is urgently needed.
Psychometric properties of the WHO Violence Against Women instrument in a male population-based sample in Sweden
Authors: Nybergh Lotta , Taft Charles , Krantz Gunilla
Published: November 2012

Objectives

To explore the psychometric properties of the WHO's Violence Against Women instrument (VAWI) in a randomly selected national sample of Swedish men.

Design

Cross-sectional survey study.

Setting

Sweden.

Participants

A postal survey was sent to 1009 men between January and March 2009, during which 458 men (45.4%) returned the questionnaire. 49 men who did not answer any of the violence items were excluded from the analyses, resulting in a final sample of 399 men.

Primary and secondary outcome measures

Self-reported exposure to psychological, physical and sexual intimate partner violence.

Results

Cronbach's α were 0.74 (psychological scale), 0.86 (physical scale), 0.82 (sexual scale) and 0.88 (total scale). Principal components analysis did not corroborate the conceptual three-dimensional model of the VAWI and other constructs were found. Past-year prevalence of physical (7.6%; 95% CI 5.0%  to 10.2%) and sexual (2.3%; 95% CI 0.8% to 3.8%) violence was higher than in other Nordic studies; earlier-in-life prevalence of physical violence (6.8%; CI 95% 4.3% to 9.3%) was lower and sexual violence (2.5%; 95% CI 1.0% to 4.0%) was higher. Reported exposure rates were generally higher than those obtained from a concurrently administered instrument (NorVold Abuse Questionnaire).

Conclusions

The VAWI conceptual model was only partially replicated and boundaries between psychological, physical and sexual acts of violence were indistinct among men exposed to intimate partner violence (IPV). This finding suggests that there is need for research instruments assessing intimate partner violence to be validated separately in male and female samples in order to ensure their suitability for the respective groups. Furthermore, theoretical frameworks for understanding men's exposure to intimate partner violence need to be advanced and should serve to guide in the development and evaluation of gender-specific IPV assessment instruments.
The effects of human umbilical cord perivascular cells on rat hepatocyte structure and functional polarity
Authors: Gómez-Aristizábal Alejandro , Davies John Edward
Published: November 2012

Hepatocyte culture is a useful tool for the study of their biology and the development of bioartificial livers. However, many challenges have to be overcome since hepatocytes rapidly lose their normal phenotype in vitro. We have recently demonstrated that human umbilical cord perivascular cells (HUCPVCs) are able to provide support to hepatocytes. In the present study we go further into exploring the effects that HUCPVCs have in the functional polarization, and both the internal and external organization, of hepatocytes. Also, we investigate HUCPVC–hepatocyte crosstalk by tracking both the effects of HUCPVCs on hepatocyte transcription factors and those of hepatocytes on the expression of hepatotrophic factors in HUCPVCs. Our results show that HUCPVCs maintain the functional polarity of hepatocytes ex vivo, as judged by the secretion of fluorescein into bile canaliculi, for at least 40 days. Transmission electron microscopy revealed that hepatocytes in coculture organize in an organoid-like structure embedded in extracellular matrix surrounded by HUCPVCs. In coculture, hepatocytes displayed a higher expression of C/EBPα, implicated in maintenance of the mature hepatocyte phenotype, and HUCPVCs upregulated hepatocyte growth factor and Jagged1 indicating that these genes may play important roles in HUCPVC–hepatocyte interactions.
Exact solution of the unsteady Krook kinetic model and nonequilibrium thermodynamic study for a rarefied gas affected by a nonlinear thermal radiation field
Authors: Abdel Wahid Taha Zakaraia
Published: November 2012

A development of the previous paper (J. Non-Equilib. Thermodyn. 36, 75 (2011)) is introduced. The nonstationary Krook kinetic equation model for a rarefied gas affected by nonlinear thermal radiation field is solved, instead of the stationary equation. In a frame comoving with the fluid, analytically the Bhatnager–Gross–Krook model kinetic equation is applied. The travelling wave solution method is used to get the exact solution of the nonlinear partial differential equations. These equations were produced from applying the moment method to the unsteady Boltzmann equation. Now we should solve nonlinear partial differential equations in place of nonlinear ordinary differential equations, which represent an arduous task. The unsteady solution gives the problem a great generality and more applications. The new problem is investigated to follow the behavior of the macroscopic properties of the gas, such as the temperature and concentration. They are substituted into the corresponding two-stream maxiwallian distribution functions permitting us to investigate the nonequilibrium thermodynamic properties of the system (gas particles + the heated plate). The entropy, entropy flux, entropy production, thermodynamic forces, and kinetic coefficients are obtained. We investigate the verification of the Boltzmann H-theorem, Le Chatelier principle, the second law of thermodynamic and the celebrated Onsager's reciprocity relation for the system. The ratios between the different contributions of the internal energy changes based upon the total derivatives of the extensive parameters are estimated via the Gibbs formula. The results are applied to helium gas for various radiation field intensities due to different plate temperatures. Graphics illustrating the calculated variables are drawn to predict their behavior and the results are discussed.
AN EXACT SOLUTION TO THE QUANTIZED ELECTROMAGNETIC FIELD IN D-DIMENSIONAL DE SITTER SPACE–TIMES
Authors: ALENCAR G. , GUEDES I. , LANDIM R. R. , FILHO R. N. COSTA
Published: November 2012

In this work, we investigate the quantum theory of light propagating in D-dimensional de Sitter space–times. To do so, we use the method of dynamic invariants to obtain the solution of the time-dependent Schrödinger equation. The quantum behavior of the electromagnetic field in this background is analyzed. As the electromagnetism loses its conformality in D≠4, we point out that there will be particle production and comoving objects will feel a Bunch–Davies thermal bath. This may become important in extra dimension physics and raises the intriguing possibility that precise measurements of the Cosmic Microwave Background could verify the existence of extra dimensions.
VISUAL-BASED HUMAN ACTION RECOGNITION ON SMART PHONES BASED ON 2D AND 3D DESCRIPTORS
Authors: BOSCH-JORGE MARC , SÁNCHEZ-SALMERÓN ANTONIO-JOSÉ , RICOLFE-VIALA CARLOS
Published: November 2012

The aim of this work is to present a visual-based human action recognition system which is adapted to constrained embedded devices, such as smart phones. Basically, vision-based human action recognition is a combination of feature-tracking, descriptor-extraction and subsequent classification of image representations, with a color-based identification tool to distinguish between multiple human subjects. Simple descriptors sets were evaluated to optimize recognition rate and performance and two dimensional (2D) descriptors were found to be effective. These sets installed on the latest phones can recognize human actions in videos in less than one second with a success rate of over 82%.
FPGA IMPLEMENTATION OF HIGH SPEED AND LOW POWER ARCHITECTURES FOR IMAGE SEGMENTATION USING SOBEL OPERATORS
Authors: KHALID ABDUL RAOUF , PAILY ROY
Published: November 2012

In this paper we present two architectures for image segmentation using Sobel Operators. The first architecture is designed for optimum speed whereas the second one is designed for low power. To improve the speed of operation and to reduce the memory access two identical processing units operate parallelly. The first architecture is able to segment up to 800 images each of 640 × 480 pixels in one second at 500 MHz clock frequency consuming 27.31 mW dynamic power. The second architecture is able to segment up to 488 images each of 640 × 480 pixels in one second at 300 MHz clock frequency consuming 13.6 mW dynamic power.
CONTROL OF SHUNT REACTOR OVERVOLTAGES BY CONTROLLED SWITCHING DURING POWER SYSTEM RESTORATION
Authors: SADEGHKHANI IMAN , KETABI ABBAS , FEUILLET RENE
Published: November 2012

The shunt reactors located on both line terminals and substation bus-bars are commonly used on long extra high voltage (EHV) transmission systems for controlling voltage during load variations. In a small power system that appears in an early stage of a black start of a power system, an overvoltage could be caused by core saturation on the energization of a shunt reactor with residual flux. The most effective method for the limitation of the switching overvoltages is controlled switching since the magnitudes of the produced transients are strongly dependent on the closing instants of the switch. A harmonic index has been introduced that it's minimum value is corresponding to the best-case switching time. In addition, in this paper an artificial neural network (ANN) is used to estimate the optimum switching instants for real time applications. ANN is trained with equivalent circuit parameters of the network, so that developed ANN is applicable to every studied system. To verify the effectiveness of the proposed index and accuracy of the ANN-based approach, two case studies are presented and demonstrated.
SECURE COLLABORATIVE INTEGRITY VERIFICATION FOR HYBRID CLOUD ENVIRONMENTS
Authors: ZHU YAN , WANG SHANBIAO , HU HONGXIN , AHN GAIL-JOON , MA DI
Published: November 2012

A hybrid cloud is a cloud computing environment in which an organization provides and manages some internal resources and has others provided externally. However, this new environment could bring irretrievable losses to the clients due to a lack of integrity verification mechanism for distributed data outsourcing. To support scalable service and data migration, in this paper we address the construction of a collaborative integrity verification mechanism in hybrid clouds where we consider the existence of multiple cloud service providers to collaboratively store and maintain the clients' data. We propose a collaborative provable data possession scheme adopting the techniques of homomorphic verifiable responses and hash index hierarchy. In addition, we articulate the performance optimization mechanisms for our scheme and prove the security of our scheme based on multi-prover zero-knowledge proof system, which can satisfy the properties of completeness, knowledge soundness, and zero-knowledge. Our experiments also show that our proposed solution only incurs a small constant amount of communications overhead.