bluuebunny/crossref_metadata_2025 huggingface dataset:
Software for Extraction of Cell Properties from Dielectrophoretic Data using Well Electrode
Authors: Teck Chee Lim , Abdul Razak Mohd Azhar
Published: March 2013

Dielectrophoresis (DEP) method offers a lot of advantages such as cell characterization and separation on mixtures of cells in modern laboratories. By knowing the cells characteristic, separation of any interested cells from blood or other biological fluids could be performed for medical diagnostic research. Additionally, the effect of drugs to cell could be investigated further. In this study, a user friendly software has been developed using GUI Matlab to extract the properties of cell from dielectrophoretic data. The data contains changes of light intensity of the moving cells under the influenced of DEP force in the DEP well electrode. The intensity is measured from a series of images captured by a microscope. By fitting the model curve to the dielectrophoretic data with two friendly functions namely Auto Plot and Auto Fit, user is able to extract the cell properties faster. In this study, the results of live and dead yeast cell properties were successfully determined based on a total of six dielectrophoretic data.
Development of Biomedical Image Processing Software Package for New Learners
Authors: Mahmood Nasrul Humaimi , Chen Hsieng Lee , Daud Siti Asmah
Published: March 2013

Biomedical image processing techniques involve a lot of mathematical equations and new learners need to calculate manually in order to analyze such techniques. It is therefore very important that they understand the biomedical image processing through live demonstration to add to their understanding of the techniques. This research will enable the biomedical students and staff, who are new learners in medical image processing, to use a software package that can analyze various techniques of biomedical image processing. It is one of the alternative ways to improve their learning process. Moreover, developing this user friendly software package using the Matrix Laboratory (MATLAB) will bring a lot of benefits to the users. Among the benefits of the software are shortening the time to process an image and helping the new learners to study about image processing because they can observe the particular object rather than just applying mathematical equations.
On–Chip Droplets Sensing using Capacitive Technique
Authors: Abdullah Mohamad Faizal , Leow P. L. , Abd Razak M. A. , Che Harun F. K.
Published: March 2013

Significant attention has been given on the development of droplets–based microfluidic system because of its potential and apparent advantages. Beside the advantages of reducing the sample volume, it’s also offer less time consuming for the analysis. Optical and fluorescence among the famous method that was used in detection of droplets but they are normally bulky, expensive and not easily accessed. This paper proposed a simple, low cost and high sensitivity for droplets sensing in microfluidic devices by using capacitive sensor. Coplanar electrodes are used to form a capacitance through the microfluidic channel. The design of eight pair of electrodes was used to detect the presence of a droplet. Changes in capacitance due to the presence of a droplet in the sensing area is detected and used to trigger the microscope to capture the image of detected droplets in microchannel. The measurement of droplets detected and counting are displayed through a LABVIEW interface in the real time.
Development of AlGaN-based graded-index-separate-confinement-heterostructure deep UV emitters by molecular beam epitaxy
Authors: Sun Haiding , Woodward Jeff , Yin Jian , Moldawer Adam , Pecora Emanuele F. , Nikiforov Alexey Yu. , Dal Negro Luca , Paiella Roberto , Ludwig Karl , Smith David J. , Moustakas Theodore D.
Published: March 2013

The authors report on the growth, structure, and emission properties of AlGaN double heterostructures having a graded-index-separate-confinement-heterostructure design. These devices were grown on the Si-face of 6H-SiC substrates by plasma-assisted molecular-beam epitaxy. The active region of the device consists of 75-nm thick Al0.72Ga0.28N film, confined by two 50-nm thick compositionally graded AlxGa1−xN films (x = 1–0.8 and x = 0.8–1) and two AlN cladding layers. X-ray diffraction and transmission electron microscopy provide evidence that the compositionally graded AlGaN layer may also be serving as a strain transition buffer, by blocking threading defects in the vicinity of the AlN/AlGaN heterointerface. Polarization dependent photoluminescence studies indicate that the emission from these structures at 257 nm is transverse magnetic polarized. Simulation studies indicate that the vertical confinement of the optical mode in these structures is 32.5% and simulations of the band structure indicate the formation of a p-n junction resulting from polarization-induced doping. Electron-beam pumping of these structures provides evidence of the onset of stimulated emission at room temperature.
A hybrid metal artifact reduction algorithm for x‐ray CT
Authors: Zhang Yanbo , Yan Hao , Jia Xun , Yang Jian , Jiang Steve B. , Mou Xuanqin
Published: March 2013

Purpose:

Presence of metal artifacts is a major reason of degradation of computed tomography image quality and there is still no standard solution to this issue. A class of recently investigated metal artifact reduction (MAR) methods based on forward projection of a prior image that is artifact‐free to replace the metal affected projection data have shown promising results. However, usually it is hard to get a good prior image which is close to the true image without artifacts. This work aims at creating a good prior image so that the forward projection can replace the metal affected projection data well.

Methods:

The proposed method consists of four steps based on the forward projection MAR framework. First, metal implants in the reconstructed image are segmented and the corresponding metal traces in the projection domain are identified. Then the prior image is obtained by two steps. A processed precorrected image is generated as an initial prior image first and then in the next step it is used as the initial image of the iterative reconstruction from the unaffected projection data to generate a better prior image. In order to deal with severe artifacts, the iteration incorporates the total variation minimization constraint as well as a novel constraint which forces the soft tissue region near metal to be as flat as possible. Finally, the projection is completed using forward projection of the prior image and the corrected image is reconstructed by FBP. A linear interpolation MAR method and two recently reported forward projection based methods are performed simultaneously for comparison.

Results:

The proposed method shows outstanding performance on both phantoms' and patients' datasets. This approach can reduce artifacts dramatically and restore tissue structures near metal to a large extent. Unlike competing MAR methods, it can effectively prevent introduction of new artifacts and false structures. Moreover, the proposed method has the lowest RMSE in regions of both soft tissue and bone tissue among the corrected images and is ranked as the best method for evaluation, by radiologists.

Conclusions:

Both subjective and quantitative evaluations of the results demonstrate the superior performance of the proposed algorithm, compared to that of the competing methods. This method offers a remarkable improvement of the image quality.
Patterns of patient specific dosimetry in total body irradiation
Authors: Akino Yuichi , McMullen Kevin P. , Das Indra J.
Published: March 2013

Purpose:

Total body irradiation (TBI) has been used for bone marrow transplant for hematologic and immune deficiency conditions. The goal of TBI is to deliver a homogeneous dose to the entire body, with a generally accepted range of dose uniformity being within ±10% of the prescribed dose. The moving table technique for TBI could make dose uniform in whole body by adjusting couch speed. However, it is difficult to accurately estimate the actual dose by calculation and hencein vivo dosimetry (IVD) is routinely performed. Here, the authors present patterns of patient‐specific IVD in 161 TBI patients treated at our institution.

Methods:

Cobalt‐60 teletherapy unit (Model C9 Cobalt‐60 teletherapy unit, Picker X‐ray Corporation) with customized moving bed (SITI Industrial Products, Inc., Fishers, IN) were used for TBI treatment. During treatment, OneDoseTM (Sicel Technology, NC) Metal Oxide‐silicon Semiconductor Field Effect Transistor detectors were placed at patient body surface; both entrance and exit side of the beam at patient head, neck, mediastinum, umbilicus, and knee to estimate midplane dose. When large differences (>10%) between the prescribed and measured dose were observed, dose delivery was corrected for subsequent fractions by the adjustment of couch speed and/or bolus placement. Under IRB exempt status, the authors retrospectively analyzed the treatment records of 161 patients who received TBI treatment between 2006 and 2011.

Results:

Across the entire cohort, the median ± SD (range) percent variance between calculated and measured dose for head, neck, mediastinum, umbilicus, and knee was −2.3 ± 10.2% (−66.2 to +35.3), 1.1 ± 11.5% (−62.2 to +40.3), −1.9 ± 9.5% (−66.4 to +46.6), −1.1 ± 7.2% (−35.2 to +42.9), and 3.4 ± 12.2% (−47.9 to +108.5), respectively. More than half of treatments were within ±10% of the prescribed dose for all anatomical regions. For 80% of treatments (10%–90%), dose at the umbilicus was within ±10%. However, some large differences greater than 35% were also found at several points. For one case, the knee received double the prescribed dose. When the dose differences for multiple fractions were averaged, compliance (±10%) between the prescription and measured dose was improved compared to the dose difference of the first single fraction, for example, as at umbilicus, which improved from 83.9% to 98.5%.

Conclusions:

Actual dose measurement analysis of TBI patients revealed a potentially wide variance from the calculated dose. Based from their IVD method for TBI using Cobalt‐60 irradiator and moving table, ±10% over entire body is hard to achieve. However, it can be significantly improved with immediate feedback after the first fraction prior to subsequent treatments.
Suppression of Metal-Insulator Transition in VO
2
by Electric Field–Induced Oxygen Vacancy Formation
Authors: Jeong Jaewoo , Aetukuri Nagaphani , Graf Tanja , Schladt Thomas D. , Samant Mahesh G. , Parkin Stuart S. P.
Published: March 2013

Mind the Vacancies

Varying the carrier density of solid-state systems to manipulate their electrical properties usually involves chemical doping, which can lead to disorder. Recently, ionic liquids have been used to form an electronic double layer on the surface of a material, tuning its carrier density by the application of an electric field.

Jeong
et al.

(p.
1402
) used liquid gating on VO
2
, which undergoes a metal-insulator transition close to room temperature. The liquid gating suppressed the transition to lower and lower temperatures; however, the material remained in the metallic state, even when the gating fluid was washed off. It appears that, instead of a simple electrostatic effect, the properties of VO
2
are modulated by the introduction of oxygen vacancies, an electrochemical consequence of high electric fields. The results imply that careful interpretation of liquid gating experiments in condensed matter physics is needed.
Simple Scaling of Catastrophic Landslide Dynamics
Authors: Ekström Göran , Stark Colin P.
Published: March 2013

Bringing Down Landslides

Measuring landslide mechanics remotely, like seismic networks are used to quantify and locate earthquakes, would provide valuable information to understand these often catastrophic and costly natural hazards.
Ekström and Stark
(p.
1416
; see the Perspective by

Petley

) analyzed global seismic network data using a method that identifies long-period events not recorded by traditional monitoring networks. The global seismic network was able to record landslide events and quantify dynamic properties—including duration, total mass, and direction of debris flow. The analysis located and quantified a series of seven previously undocumented massive landslides associated with the Siachen Glacier in the Himalayas.
Robotic Walking in the Real World
Authors: Hunt Melany L.
Published: March 2013

Studies of the mechanical stresses on plates moving through loose materials were used to simulate and optimize robot locomotion over soft ground.

[Also see Report by

Li
et al.

]
Drug Patents at the Supreme Court
Authors: Hemphill C. Scott , Sampat Bhaven
Published: March 2013

Arguments for paying generic drug makers to abandon patent challenges may rest on dubious assumptions.
A Transition in the Middle Ear
Authors: Fekete Donna M. , Noden Drew M.
Published: March 2013

A new view of mammalian middle ear development may prompt reconsideration of its evolution.

[Also see Report by
Thompson and Tucker
]
Austrian Academy of Sciences Faces Its Nazi History
Authors: Wald Chelsea
Published: March 2013

The new exhibit, the academy's first extended examination of its actions during the Nazi period, coincides with the 75th anniversary of Austria's annexation to Germany.
A Rescue Mission for Amphibians at the Brink of Extinction
Authors: Stone Richard
Published: March 2013

An amphibian research laboratory is slated to open in Panama and researchers are producing embryos from the tissue of extinct species.
Life Could Have Thrived on Mars, but Did It? Curiosity Still Has No Clue
Authors: Kerr Richard A.
Published: March 2013

For the first time, scientists have shown that life as we know it could have survived—but martian life remains elusive.
Suresh Leaves His Mark on NSF as He Heads to Carnegie Mellon
Authors: Mervis Jeffrey
Published: March 2013

Outgoing National Science Foundation director hopes initiatives on interdisciplinary research, global partnerships, and entrepreneurship will be sustained.
Association of γδ T Cells with Disease Severity and Mortality in Septic Patients
Authors: Andreu-Ballester Juan C. , Tormo-Calandín Constantino , Garcia-Ballesteros Carlos , Pérez-Griera J. , Amigó Victoria , Almela-Quilis Amadeo , Ruiz del Castillo Juan , Peñarroja-Otero Carlos , Ballester Ferran
Published: March 2013

Gamma-delta T cells are the most abundant of all epithelial-resident lymphocytes and are considered a first line of defense against pathogens in the mucosa. Our objective was to confirm the reduction in γδ T cell subsets and its relationship with mortality in patients with sepsis. We studied 135 patients with sepsis attended in the emergency department and intensive care unit of two hospitals and compared them with a similar control group of healthy subjects. The αβ and γδ T cell subsets were determined via flow cytometry according to the stage of the sepsis and its relationship with mortality. All the lymphocyte subsets were reduced with respect to the corresponding subsets in the control group. All the γδ T cell populations decreased significantly as the septic picture worsened. Furthermore, γδ T cells showed decreases at days 2, 3, and 4 from the start of sepsis. Twenty-six patients with sepsis died (19.3%). The γδ T cells, specifically, the CD3+CD56+γδ T cells, were significantly reduced in those septic patients who died. Our results indicate that, during sepsis, γδ T cells show the largest decrease and this reduction becomes more intense when the septic process becomes more severe. Mortality was associated with a significant decrease in γδ T cells.
Direct Bacterial Identification in Positive Blood Cultures by Use of Two Commercial Matrix-Assisted Laser Desorption Ionization–Time of Flight Mass Spectrometry Systems
Authors: Chen Jonathan H. K. , Ho Pak-Leung , Kwan Grace S. W. , She Kevin K. K. , Siu Gilman K. H. , Cheng Vincent C. C. , Yuen Kwok-Yung , Yam Wing-Cheong
Published: March 2013

Matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS) for the identification of bacteria and fungi was recently introduced in microbiology laboratories. This technology could greatly improve the clinical management of patients and guidance for chemotherapy. In this study, we used a commercial MALDI Sepsityper extraction method to evaluate the performance of two commercial MALDI-TOF MS systems, the Vitek MS IVD (bioMérieux) and the Microflex LT Biotyper (Bruker Daltonics) for direct bacterial identification in positive blood cultures. In 181 monomicrobial cultures, both systems generated genus to species level identifications for >90% of the specimens (Biotyper, 177/181 [97.8%]; Vitek MS IVD, 167/181 [92.3%]). Overall, the Biotyper system generated significantly more accurate identifications than the Vitek MS IVD system (P= 0.016; 177 versus 167 out of 181 specimens). The Biotyper system identified the minority species among polymicrobial blood cultures. We also compared the performance of an in-house extraction method with that of the Sepsityper on both MALDI-TOF MS systems. The in-house method generated more correct identifications at the genus level than the Sepsityper (96.7% versus 93.5%) on the Biotyper system, whereas the two methods exhibited the same performance level (88.0% versus 88.0%) on the Vitek MS IVD system. Our study confirmed the practical advantages of MALDI-TOF MS, and our in-house extraction method reduced the reagent cost to $1 per specimen, with a shorter turnaround time of 3 h, which is highly cost-effective for a diagnostic microbiology service.
Rapid Spread of Vibrio cholerae O1 El Tor Variant in Odisha, Eastern India, in 2008 and 2009
Authors: Khuntia H. K. , Pal B. B. , Samal S. K. , Kar S. K.
Published: March 2013

The emergence and spread of
Vibrio cholerae
O1 El Tor variant strains causing severe diarrhea has been witnessed worldwide in recent years. In the state of Odisha, India, the spread of the
V. cholerae
O1 El Tor variant strains was studied during outbreaks in 2008 and 2009. Analysis of 194
V. cholerae
O1 Ogawa strains revealed that
V. cholerae
O1 El Tor variant strains are spreading gradually throughout the state, causing outbreaks replacing typical
V. cholerae
O1 El Tor biotype strains.
Septic Arthritis Caused by Noncapsulated Haemophilus influenzae
Authors: Le Quellec Sandra , Gaillot Olivier , Chotel Franck , Freydière Anne-Marie , Laurent Frédéric , Vandenesch François , Doléans-Jordheim Anne
Published: March 2013

Since the introduction of type b
Haemophilus influenzae
vaccination, noncapsulated
H. influenzae
has become responsible for most cases of invasive
H. influenzae
diseases. In our two cases of septic arthritis, we isolated strains with β-lactamase-positive amoxicillin-clavulanate resistance (BLPACR). Thus, the increasing prevalence of BLPACR should be taken into account when empirical therapy is chosen for septic arthritis.
CD4 and CD8 T Cells Directly Recognize Murine Gammaherpesvirus 68-Immortalized Cells and Prevent Tumor Outgrowth
Authors: Liang Xiaozhan , Crepeau Rebecca L. , Zhang Weijun , Speck Samuel H. , Usherwood Edward J.
Published: March 2013

There has been extensive research regarding T cell recognition of Epstein-Barr virus-transformed cells; however, less is known regarding the recognition of B cells immortalized by gamma-2 herpesviruses. Here we show that B cells immortalized by murine gammaherpesvirus 68 (MHV-68, γHV-68) can be controlled by either CD4 or CD8 T cells
in vivo
. We present evidence for the direct recognition of infected B cells by CD4 and CD8 T cells. These data will help in the development of immunotherapeutic approaches combating gamma-2 herpesvirus-related disease.
Merkel Cell Polyomavirus Large T Antigen Has Growth-Promoting and Inhibitory Activities
Authors: Cheng Jingwei , Rozenblatt-Rosen Orit , Paulson Kelly G. , Nghiem Paul , DeCaprio James A.
Published: March 2013

Merkel cell carcinoma (MCC) is a rare and aggressive form of skin cancer. In at least 80% of all MCC, Merkel cell polyomavirus (MCPyV) DNA has undergone clonal integration into the host cell genome, and most tumors express the MCPyV large and small T antigens. In all cases of MCC reported to date, the integrated MCPyV genome has undergone mutations in the large T antigen. These mutations result in expression of a truncated large T antigen that retains the Rb binding or LXCXE motif but deletes the DNA binding and helicase domains. However, the transforming functions of full-length and truncated MCPyV large T antigen are unknown. We compared the transforming activities of full-length, truncated, and alternatively spliced 57kT forms of MCPyV large T antigen. MCPyV large T antigen could bind to Rb but was unable to bind to p53. Furthermore, MCPyV-truncated large T antigen was more effective than full-length and 57kT large T antigen in promoting the growth of human and mouse fibroblasts. In contrast, expression of the MCPyV large T antigen C-terminal 100 residues could inhibit the growth of several different cell types. These data imply that the deletion of the C terminus of MCPyV large T antigen found in MCC serves not only to disrupt viral replication but also results in the loss of a distinct growth-inhibitory function intrinsic to this region.
Molecular Basis of the Receptor Binding Specificity Switch of the Hemagglutinins from both the 1918 and 2009 Pandemic Influenza A Viruses by a D225G Substitution
Authors: Zhang Wei , Shi Yi , Qi Jianxun , Gao Feng , Li Qing , Fan Zheng , Yan Jinghua , Gao George F.
Published: March 2013

Influenza A virus uses sialic acids as cell entry receptors, and there are two main receptor forms, α2,6 linkage or α2,3 linkage to galactose, that determine virus host ranges (mammalian or avian). The receptor binding hemagglutinins (HAs) of both 1918 and 2009 pandemic H1N1 (18H1 and 09H1, respectively) influenza A viruses preferentially bind to the human α2,6 linkage receptor. A single D225G mutation in both H1s switches receptor binding specificity from α2,6 linkage binding to dual receptor binding. However, the molecular basis for this specificity switch is not fully understood. Here, we show via H1-ligand complex structures that the D225G substitution results in a loss of a salt bridge between amino acids D225 and K222, enabling the key residue Q226 to interact with the avian receptor, thereby obtaining dual receptor binding. This is further confirmed by a D225E mutant that retains human receptor binding specificity with the salt bridge intact.
Downregulation of Nipah Virus N mRNA Occurs through Interaction between Its 3′ Untranslated Region and hnRNP D
Authors: Hino Kimihiro , Sato Hiroki , Sugai Akihiro , Kato Masahiko , Yoneda Misako , Kai Chieko
Published: March 2013

Nipah virus (NiV) is a nonsegmented, single-stranded, negative-sense RNA virus belonging to the genus
Henipavirus
, family
Paramyxoviridae
. NiV causes acute encephalitis and respiratory disease in humans, is associated with high mortality, and poses a threat in southern Asia. The genomes of henipaviruses are about 18,246 nucleotides (nt) long, which is longer than those of other paramyxoviruses (around 15,384 nt). This difference is caused by the noncoding RNA region, particularly the 3′ untranslated region (UTR), which occupies more than half of the noncoding RNA region. To determine the function(s) of the NiV noncoding RNA region, we investigated the effects of NiV 3′ UTRs on reporter gene expression. The NiV N 3′ UTR (nt 1 to 100) demonstrated strong repressor activity associated with hnRNP D protein binding to that region. Mutation of the hnRNP D binding site or knockdown of hnRNP D resulted in increased expression of the NiV N 3′ UTR reporter. Our findings suggest that NiV N expression is repressed by hnRNP D through the NiV N 3′ UTR and demonstrate the involvement of posttranscriptional regulation in the NiV life cycle. To the best of our knowledge, this provides the first report of the functions of the NiV noncoding RNA region.
Glycoprotein H and α4β1 Integrins Determine the Entry Pathway of Alphaherpesviruses
Authors: Azab Walid , Lehmann Maik J. , Osterrieder Nikolaus
Published: March 2013

Herpesviruses enter cells either by direct fusion at the plasma membrane or from within endosomes, depending on the cell type and receptor(s). We investigated two closely related herpesviruses of horses, equine herpesvirus type 1 (EHV-1) and EHV-4, for which the cellular and viral determinants routing virus entry are unknown. We show that EHV-1 enters equine epithelial cells via direct fusion at the plasma membrane, while EHV-4 does so via an endocytic pathway, which is dependent on dynamin II, cholesterol, caveolin 1, and tyrosine kinase activity. Exchange of glycoprotein H (gH) between EHV-1 and EHV-4 resulted in rerouting of EHV-1 to the endocytic pathway, as did blocking of α4β1 integrins on the cell surface. Furthermore, a point mutation in the SDI integrin-binding motif of EHV-1 gH also directed EHV-1 to the endocytic pathway. Cumulatively, we show that viral gH and cellular α4β1 integrins are important determinants in the choice of alphaherpesvirus cellular entry pathways.
Nuclear Targeting of Human Cytomegalovirus Large Tegument Protein pUL48 Is Essential for Viral Growth
Authors: Brock Ivonne , Krüger Marc , Mertens Thomas , von Einem Jens
Published: March 2013

We report the identification of a functional nuclear localization signal (NLS) in the human cytomegalovirus (HCMV) large tegument protein pUL48 that is required for nuclear localization in transfected cells and is essential for viral growth. The NLS was mapped to pUL48 amino acid residues 284 to 302. This sequence contains a bipartite NLS comprising two clusters of basic residues (bC1 and bC2) separated by 9 amino acids. Deletion or mutation of bC1 or mutation of bC2 abrogated the nuclear localization of full-length pUL48 in transiently expressing cells, thus strongly implying a bipartite character of the NLS. Nuclear localization could be restored by fusion of a functional NLS together with enhanced green fluorescent protein (EGFP) to the N terminus of these mutants. In HCMV-infected cells, pUL48 was found in both nuclear and cytoplasmic fractions, supporting a function of the NLS during virus infection. NLS mutant viruses, generated by markerless bacterial artificial chromosome mutagenesis, were not viable in cell culture, whereas coexpression of pUL48 complemented growth of these mutants. The fusion of a functional NLS to the N terminus of pUL48 in a nonviable NLS mutant virus partially rescued the growth defect. Furthermore, the replacement of the bipartite pUL48 NLS by the monopartite pUL36 NLS of herpes simplex virus 1 supported viral growth to some extent but still revealed a severe defect in focus formation and release of infectious virus particles. Together, these results show that nuclear targeting of pUL48 is mediated by a bipartite NLS whose function is essential for HCMV growth.
An ICU patient with spots and a peculiar pneumonia
Authors: Hamers Patricia A H , Thijsen Steven F T , van der Griend René , Haas Lenneke E M
Published: March 2013

This is the first report of varicella zoster virus (VZV) pneumonia in an adult patient treated with rituximab because of autoimmune haemolytic anaemia and it illustrates that a VZV infection should be considered when an immunocompromised patient develops pulmonary symptoms, even in the absence of cutaneous lesions. It also depicts the importance of performing varicella serology in patients receiving multiple immunosuppressive agents.
Birt-Hogg-Dubé syndrome: a rare cause of cystic lung diseases
Authors: Mohan Das Lekshmi , Rang Catherine Elizabeth Jule , Banka Rajesh
Published: March 2013

Cystic lung diseases are characterised by multiple intrapulmonary cysts. They can be mimicked by other more common causes of focal parenchymal lucencies such as emphysema, bronchiectasis and honeycombing. The various conditions have differing managements and prognoses, thus correct evaluation is essential. Birt-Hogg-Dubé (BHD) syndrome is an autosomal dominant disorder, that is, a rare cause of cystic lung disease. It is seen in approximately 200 families worldwide. This case describes a 37-year-old woman who presented to a District General Hospital with symptoms of pleuritic chest pain and breathlessness. A CT pulmonary angiogram arranged to assess for pulmonary emboli excluded this but it demonstrated multiple intrapulmonary cysts. After further investigation and subsequent genetic testing this was confirmed to be BHD syndrome.
Laparoscopic repair of a late-presenting Bochdalek diaphragmatic hernia with acute gastric volvulus
Authors: Hadjittofi Christopher , Matter Ibrahim , Eyal Ori , Slijper Nadav
Published: March 2013

An otherwise healthy 17-year-old boy presented to the paediatric emergency department with acute severe epigastric pain. An admission abdominal radiograph demonstrated gastric dilation, associated with an elevated left hemidiaphragm. Subsequent barium contrast imaging confirmed the diagnosis of organoaxial acute gastric volvulus (AGV). Emergent exploratory laparoscopy revealed AGV with migration of the stomach, spleen, pancreatic tail, splenic flexure, left kidney and adrenal through a left-sided Bochdalek diaphragmatic hernia. Following careful mobilisation of the displaced structures, a mesh closure of the diaphragmatic defect was performed. The patient's postoperative chest radiograph was unremarkable, and he was discharged on the sixth postoperative day after an uneventful recovery. At 2 months the patient was well and asymptomatic, with normal barium contrast imaging results.
Cleidocranial dysplasia: complete clinical, radiological and histological profiles
Authors: Vij Ruchieka , Batra Puneet , Vij Hitesh
Published: March 2013

Cleidocranial dysplasia is an autosomal-dominant condition characterised by widely patent calvarial sutures, clavicular hypoplasia, supernumerary teeth and short stature. Though it is not a very uncommon occurrence, its histopathological features are not frequently reported. This paper presents a similar case with complete clinical, radiological, histological and treatment profiles.
Self-reported feelings of anger and aggression towards others in patients on levetiracetam: data from the UK antiepileptic drug register
Authors: Wieshmann Udo Carl , Baker Gus A
Published: March 2013

Objectives

To ascertain the frequency of self-reported anger and depression in levetiracetam (LEV).

Design

We compared patients with epilepsy (PWE) taking LEV with PWE taking other antiepileptic drugs (AEDs).

Setting

All PWE and controls submitted information to the UK AED register.

Participants

We analysed the data of 418 PWE and 41 control participants. 158 participants took LEV in monotherapy or as part of polypharmacotherapy, 260 PWE took other AED.

Primary and secondary outcome measures

All PWE and controls completed the Liverpool Adverse Event Profile (LAEP) which includes items on anger and depression quantified on a four-point Likert scale, with 1 indicating that there was never a problem; 2, rarely a problem; 3, sometimes a problem and 4, always or often a problem.

Results

49% of PWE on LEV and 39% on AED other than LEV reported anger as sometimes or always being a problem (p=0.042). 48% of PWE on LEV and 45% on AED other than LEV reported depression as sometimes or always being a problem (p=0.584). 7% of control participants reported anger as sometimes being a problem and 93% reported anger as never or rarely being a problem. Depression was never a problem in 75% of controls and rarely a problem in 25%.

Conclusions

Anger and depression were more frequently reported as a problem by PWE than by control participants. Our observational register of self-reported symptoms suggested anger being more often a problem in patients taking LEV than in PWE taking other AED. PWE should be informed about this potential problem of LEV.
Learning curve of Wingspan stenting for intracranial atherosclerosis: single-center experience of 95 consecutive patients
Authors: Yu Simon Chun Ho , Leung Thomas Wai Hong , Lee Kwok Tung , Wong Lawrence Ka Sing
Published: March 2013

Background

Symptomatic brain hemorrhage was a significant cause of periprocedural stroke or death following stenting in the Stenting and Aggressive Medical Management for Preventing Recurrent Stroke in Intracranial Stenosis trial, which called into question the safety of Wingspan stenting for intracranial atherosclerosis. This study analyzed the role of a learning curve in the safety and outcome of Wingspan stenting from the experience of 95 consecutive patients at a single center.

Methods

In this prospective study the endpoints were major stroke or death (modified Rankin Scale score >3) within 30 days, other neurological complications, technical procedural problems, technical success in completion of angioplasty and stenting and recurrent ischemic stroke in the corresponding vascular territory after 30 days. Data splitting into quarters was used for learning curve analysis.

Results

The periprocedural major stroke or death rate was 4.2% (4/95), minor stroke rate was 5.3% (5/95), total 9.5% (9/95). The technical procedural problem rate was 11.6% (11/95) and the technical success rate was 93.7% (89/95). The 89 patients were followed for 38.9±22.7 months (median 40.8, range 0.2–72, 3463 patient-months) after stenting. The risk of recurrent ischemic stroke in the corresponding vascular territory was 0.7% per patient per year (2/3463 patient-months). Guidewire- or angioplasty-related hemorrhage was the major cause of periprocedural major stroke or death (3/4, 75%) and did not occur in the last quarter. Periprocedural intracerebral hemorrhage was uncommon and perforator stroke did not occur.

Conclusions

There may be a learning curve for mastering the safety precautions of Wingspan stenting for intracranial atherosclerosis.
Variation in cost of newly qualified doctors' prescriptions: a review of data from a hospital electronic prescribing system
Authors: Nwulu Ugochi , Hodson James , Thomas Sarah K , Westwood David , Griffin Charlotte , Coleman Jamie J
Published: March 2013

Purpose of the study

To investigate the variation in the net ingredient cost (NIC) of the medications most commonly prescribed by Foundation Year 1 (F1) doctors in a teaching hospital and to compare the effects of working in different specialties and rotations on this cost.

Design of the study

Retrospective review of prescription data from 5 August 2010 to 3 August 2011 extracted from an electronic prescribing system.

Results

The F1 doctors generated 81 316 prescriptions with an estimated total cost of £579 398. The mean NIC per doctor was £7334 (SE=£430). Prescribing costs varied significantly across clinical departments and between drug classes considered in the analysis. Specifically, prescribing in the infection and respiratory drug categories and within the trauma and orthopaedics department was associated with higher prescribing costs. Significant variability was also attributable to the prescribing doctor (p<0.001) with average prescription costs ranging from 72.2% lower to 193.8% higher than the median doctor.

Conclusions

There is considerable variation in the total costs of medications prescribed by F1 doctors, even after considering a range of prescription factors. This variation may suggest that some doctors are prescribing uneconomically relative to the rest of the cohort. Knowledge of which clinical areas and drug classes have higher NICs may allow an alternative focus for medicine management teams and postgraduate education.
Unveiling the paradoxical nature of myelodysplastic syndromes (MDS): Why hypercellular marrow strongly favors accelerated apoptosis
Authors: Das Madhurima , Chaudhuri Samaresh , Law Sujata
Published: March 2013

The pathogenesis of bone marrow failure in myelodysplastic syndromes (MDS) is an unresolved mystery. MDS causes peripheral blood cytopenias and increased bone marrow cellularity. This apparent paradox has been interpreted as a sign of intramedullary destruction of a substantial portion of the developing hematopoietic cells by apoptosis. The present study aimed to delineate the exact mechanistic relationship between the bone marrow hypercellularity and the accelerated apoptosis in an N-ethyl-N-nitrosourea (ENU)-induced experimental MDS mouse model. The observations made so far clarify the quantitative and qualitative changes that occur in the bone marrow microenvironment through cell cycle analysis, especially involving the telomerase reverse transcriptase (TERT) and p53 expression patterns. The survival fate of the bone marrow cells were observed by measuring the expression level of some intracellular protein molecules like apoptosis signal-regulating kinase 1 (ASK-1), c-Jun N-terminal kinase (JNK), and cleaved caspase-3 of the extrinsic pathway toward apoptosis. We found myelodysplasia damage occurs within one or more multipotent progenitor populations resulting in uncontrolled cellular proliferation within the MDS bone marrow. Then, due to homeostatic balance, this high cellular burden is minimized by activating the apoptosis pathway. As a result, the peripheral blood suffers cellular deprivation. This study can throw some light on the mechanism of disease progression and also help to reveal the paradoxical nature of the disease.
Investigation of field-installation effects of horizontal twin-jet grouting in Shanghai soft soil deposits
Authors: Wang Zhi-Feng , Shen Shui-Long , Ho Chu-Eu , Kim Yong-Hyun
Published: March 2013

This paper presents a case study of an investigation into the responses of the surrounding ground to the horizontal twin-jet grouting method (HTJGM) in soft soil deposits of Shanghai. During the field test, the variation of pore-water pressure, lateral earth pressure, lateral displacements of the subsurface soils, and ground surface heave induced by the installation of five horizontal jet-grouted columns were monitored. The monitoring results indicate that the excess pore-water pressure reached 4 to 6 times the undrained shear strength of the soils, while maximum lateral displacements and ground surface heave were up to 80 and 17 mm, respectively. The influence range due to the installation of jet-grouted columns was between 15 and 20 times the nominal column radius. The development of prediction methods for lateral displacements and ground surface heave induced by the HTJGM installation process are presented and discussed. Results from the investigation suggest that the proposed prediction methods can be used to provide reasonable estimates of ground response and influence range of horizontal jet grouting.
Time-dependent density functional theory study on the electronic excited-state hydrogen bonding dynamics of BHC-nicotinamide in MeOH solution
Authors: Cheng Jinling , Liu Di
Published: March 2013

The density functional theory (DFT) and time-dependent density functional theory (TDDFT) methods were performed to investigate the electronic excited-state hydrogen bonding dynamics of the hydrogenbonded complex formed by BHC-nicotinamide (BHCN) and methanol (MeOH). The ground-state geometry optimizations, electronic transition energies, corresponding oscillation strengths of the low-lying electronically excited states, and the optimized S1 excited-state geometry for the isolated BHCN and MeOH monomers, the hydrogen-bonded BHCN–MeOH dimers, and BHCN–2MeOH trimer complexes have been calculated by using the DFT and TDDFT methods, respectively. We have demonstrated that the intermolecular hydrogen bond C10=O14···H40−O39−Me is weaker than C16=O17···H46−O45−Me in the hydrogen-bonded dimers and trimer no matter whether in the ground state or the excited state. In addition, our results are consistent with the relationship between the electronic spectral shifts and excited-state hydrogen bonding dynamics: hydrogen bond strengthening can induce the relative electronic spectra redshift, whereas a blueshift will be induced. In addition, we focused our attention on the frontier molecular orbital and the results could reasonably explain the hydrogen bond strengthening or weakening mechanism.
The reaction mechanism of chiral hydroxylation of p-OH and p-NH2 substituted compounds by ethylbenzene dehydrogenase
Authors: Dudzik Agnieszka , Kozik Bartłomiej , Tataruch Mateusz , Wójcik Anna , Knack Daniel , Borowski Tomasz , Heider Johann , Witko Małgorzata , Szaleniec Maciej
Published: March 2013

Ethylbenzene dehydrogenase (EbDH; enzyme commission (EC) number: 1.17.99.2) is a unique biocatalyst that hydroxylates alkylaromatic and alkylheterocyclic compounds to (S)-secondary alcohols under anaerobic conditions. The enzyme exhibits a high promiscuity catalyzing oxidation of over 30 substrates, inter alia, para-substituted alkylphenols and alkylanilines. Secondary alcohols with OH and NH2 substituents in the aromatic ring are highly valuable synthons for many biologically active compounds in the fine chemical industry. EbDH hydroxylates most of the studied compounds highly enantioselectively, except for five substrates that harbour OH and NH2 groups in the para position, which exhibit a significant decrease in the percent enantiomeric excess (% ee). This phenomenon is inconsistent with the previously suggested enzyme mechanism, but it may be linked to a stabilization of the carbocation intermediate by deprotonation of the OH or NH2 substituent in the active site that yields a transient quinone (imine) ethide species. This would initiate an alternative reaction pathway involving the addition of a water molecule to a C=C double bond. This hypothesis was cross-validated by density functional theory (DFT) cluster modelling of the alternative reaction pathway with 4-ethylphenol, as well as by experimental assessment of the pH dependency of enantiomeric excesses. The results reported herein suggest that the alternative reaction pathway may significantly contribute to the overall reaction if the carbocation intermediates are stabilized by deprotonation.
Pine cones facilitate ignition of forest floor duff
Authors: Kreye Jesse K. , Varner J. Morgan , Dugaw Christopher J. , Cao Jing , Szecsei Jonathan , Engber Eamon A.
Published: March 2013

The ignition and combustion of forest floor duff are poorly understood yet have been linked to soil heating and overstory tree mortality in many temperate coniferous forests. Research to date has focused on the characteristics of duff that facilitate ignition and spread, including fuel moisture, mineral content, and depth. Field observations suggest that the presence of pine cones on and within the forest floor might facilitate ignition of intermixed forest floor fuels. We investigated the effect of cone fuel additions on the ignition of underlying forest floor from fuels collected in long-unburned longleaf pine (Pinus palustris Mill.) forests in northern Florida, USA. Fuels were wetted to threshold gravimetric moisture contents to evaluate the relative effect on ignition. In stark contrast to fuel beds without cones, in which duff ignition only occurred in 17% of samples, those with cones added ignited the underlying duff 94% of the time. Flame heights were 40% taller and flaming duration was 47% longer in fuel beds with cones. Where present, pine cones act as vectors of ignition for forest floor fuels, and their role in fires deserves more attention to enhance our understanding of forest floor combustion.
AN AREA-PRESERVING FLOW FOR CLOSED CONVEX PLANE CURVES
Authors: MAO YUEYUE , PAN SHENGLIANG , WANG YILING
Published: March 2013

Motivated by Gage [On an area-preserving evolution equation for plane curves, in Nonlinear Problems in Geometry, ed. D. M. DeTurck, Contemporary Mathematics, Vol. 51 (American Mathematical Society, Providence, RI, 1986), pp. 51–62] and Ma–Cheng [A non-local area preserving curve flow, preprint (2009), arXiv:0907.1430v2, [math.DG]], in this paper, an area-preserving flow for convex plane curves is presented. This flow will decrease the perimeter of the evolving curve and make the curve more and more circular during the evolution process. And finally, as t goes to infinity, the limiting curve will be a finite circle in the C∞ metric.
A SIMPLE METHOD TO CONSTRUCT LOCAL EQUILIBRIUM FUNCTION FOR LATTICE BOLTZMANN METHOD
Authors: WANG P. , ZHANG S. Q.
Published: March 2013

We have developed a simple method to construct local equilibrium function for lattice Boltzmann method (LBM). This new method can make LBM model satisfy compressible flow with a flexible specific-heat ratio. Test cases, including the one-dimensional Sod flow, one-dimensional Lax flow and thermal Couette flow are presented. Good results obtained using proposed new method, indicate that the proposed method is potentially capable of constructing of the local equilibrium function for LBM.
DYSON–SCHWINGER APPROACH TO STRONGLY COUPLED THEORIES
Authors: POPOVICI CARINA
Published: March 2013

Although non-perturbative functional methods are often associated with low energy Quantum Chromodynamics, contemporary studies indicate that they provide reliable tools to characterize a much wider spectrum of strongly interacting many-body systems. In this paper, we aim to provide a modest overview on a few notable applications of Dyson–Schwinger equations to QCD and condensed matter physics. After a short introduction, we lay out some formal considerations and proceed by addressing the confinement problem. We discuss in some detail the heavy quark limit of Coulomb gauge QCD, in particular the simple connection between the non-perturbative Green's functions of Yang–Mills theory and the confinement potential. Landau gauge results on the infrared Yang–Mills propagators are also briefly reviewed. We then focus on less common applications, in graphene and high-temperature superconductivity. We discuss recent developments, and present theoretical predictions that are supported by experimental findings.
VACUUM STABILITY OF THE ${\mathcal{PT}}$-SYMMETRIC (-ϕ4) SCALAR FIELD THEORY
Authors: SHALABY ABOUZEID M.
Published: March 2013

In this paper, we study the vacuum stability of the classical unstable (-ϕ4) scalar field potential. Regarding this, we obtained the effective potential, up to second-order in the coupling, for the theory in 1+1 and 2+1 space–time dimensions. We found that the obtained effective potential is bounded-from-below, which proves the vacuum stability of the theory in space–time dimensions higher than the previously studied 0+1 case. In our calculations, we used the canonical quantization regime in which one deals with operators rather than classical functions used in the path integral formulation. Therefore, the non-Hermiticity of the effective field theory is obvious. Moreover, the method we employ implements the canonical equal-time commutation relations and the Heisenberg picture for the operators. Thus, the metric operator is implemented in the calculations of the transition amplitudes. Accordingly, the method avoids the very complicated calculations needed in other methods for the metric operator. To test the accuracy of our results, we obtained the exponential behavior of the vacuum condensate for small coupling values, which has been obtained in the literature using other methods. We assert that this work is interesting, as all the studies in the literature advocate the stability of the (-ϕ4) theory at the quantum mechanical level while our work extends the argument to the level of field quantization.
CONSTRAINTS ON BACKGROUND TORSION FROM BIREFRINGENCE OF CMB POLARIZATION
Authors: DAS MOUMITA , MOHANTY SUBHENDRA , PRASANNA A. R.
Published: March 2013

We show that a nonminimal coupling of electromagnetism with background torsion can produce birefringence of the electromagnetic waves. This birefringence gives rise to a B-mode polarization of the CMB. From the bounds on CMB polarization from QUaD experiment, one can put limits on the background torsion at ξ1Ti = (2.78 ± 4.85) × 10-20 GeV-1.