bluuebunny/crossref_metadata_2025 huggingface dataset:
Assembly of Nanowires by Contact-Line Deposition
Authors: Zhang Mei , Abdelsalam Farag , McDargh Zach , Zhang Chuck , Wang Ben
Published: January 2010

The post-synthetic assembly of nanowires into desired configurations presents a unique challenge. Through the use of a microscope we observed the behaviors of different nanowires during the drying of their solutions. In addition, we also viewed the resulting dried patterns on substrates by AFM and SEM. We found that nanowires are deposited and aligned along the contact line. The evaporation-induced capillary flow carries the nanowires to the contact line and their alignment there is due to self-assembly directed by solvent evaporation. Based on our observations, we developed a contact-line-deposition process and successfully assembled aligned nanowires in proper patterns on substrates.
Silica-coated Silver Nanoparticles
Authors: Sotiriou Georgios A , Pratsinis Sotiris E.
Published: January 2010

Silver (Ag) nanoparticles dispersed in an amorphous silica (SiO2) matrix or coated by a SiO2 layer were synthesized by flame spray pyrolysis (FSP). The coated nanoparticles were produced by using a modified enclosed FSP setup, in which the SiO2 precursor was injected through a ring above the FSP nozzle at various burner-ring-distances (BRDs), after the core Ag nanoparticles had been formed. The produced nanoparticles were characterized by XRD, BET, TEM and UV/vis analysis. The Ag particle size was possible to be controlled by tuning the FSP parameters. For the SiO2 coated nanoparticles, larger Ag core sizes were obtained for higher BRDs. All the produced nanoparticles exhibited the characteristic plasmon resonance frequency of Ag nanoparticles.
Effect of Size, Shape, Composition, and Support Film on Localized Surface Plasmon Resonance Frequency: A Single Particle Approach Applied to Silver Bipyramids and Gold and Silver Nanocubes
Authors: Ringe Emilie , Zhang Jian , Langille Mark R. , Sohn Kwonnam , Cobley Claire , Au Leslie , Xia Younan , Mirkin Chad A. , Huang Jiaxing , Marks Laurence D , Van Duyne Richard P
Published: January 2010

Localized surface plasmon resonances (LSPR), collective electron oscillations in nanoparticles, are being heavily scrutinized for applications in chemical and biological sensing, as well as in prototype nanophotonic devices. This phenomenon exhibits an acute dependence on the particle’s size, shape, composition, and environment. The detailed characterization of the structure-function relationship of nanoparticles is obscured by ensemble averaging. Consequently, single-particle data must be obtained to extract useful information from polydisperse reaction mixtures. Recently, a correlated high resolution transmission electron microscopy (HRTEM) LSPR technique has been developed and applied to silver nanocubes. We report here a second generation of experiments using this correlation technique, in which statistical analysis is performed on a large number of single particles. The LSPR dependence on size, shape, material, and environment was probed using silver right bipyramids, silver cubes, and gold cubes. It was found that the slope of the dependence of LSPR peak on size for silver bipyramids increases as the edges become sharper. Also, a plasmon shift of 96 nm was observed between similar silver and gold cubes, while a shift of 26 nm was observed, for gold cubes, between substrates of refractive index (RI) of 1.5 and 2.05.
Polarization behavior of the exciton-polariton emission of ZnO-based microresonators
Authors: Sturm Chris , Hilmer Helena , Schmidt-Grund Rüdiger , Grundmann Marius
Published: January 2010

We present the polarization behavior of the exciton-polariton luminescence of a ZnO-based all-oxide resonator. A splitting in the emission energy between the s- and p-polarized pho-toluminescence of the lower polariton branch was observed which increases with increasing emission angle. It is caused by the polarization behavior of the uncoupled cavity-photon mode, and reaches a maximum of about 5 meV at an emission angle near the bottleneck region. For lar-ger angles the energy splitting decreases. Additionally to the energy splitting, we observed dif-ferences in the photoluminescence intensity which we trace back to different occupation of the lower polariton branch for the two polarizations. Whereas for p-polarization a bottleneck effect is clearly observable, this effect is much weaker for s-polarization. These findings indicate that the relaxation of hot carriers into the bottleneck region is enhanced for the p-polarized photolumi-nescence compared to the s-polarized one. The differences between these two polarizations are most pronounced for a very large negative detuning and vanish with increasing detuning.
Radiolabelling of TiO2 Nanoparticle Libraries for Toxicological Investigations
Authors: Musumeci Anthony W. , Gahan Lawrence R , Rajh Tijana , Martin Darren J , Smith Suzanne V
Published: January 2010

To further our understanding of nanoparticle interactions with biological systems, it is important that highly sensitive, reliable and robust methods for labelling particles are established. We report here the application of a series of bi-functional cage ligands to radiolabel a range (i.e. shapes and sizes) of titanium dioxide (TiO2) particles. The cages were covalently attached to the surface of the particles via the use of a dopac derivative and then radiolabelled with a gamma emitting radioisotope. The final radiolabelled nanoparticles proved to be stable in solution and the method easy and robust. The application of a gamma emitter allows the radiolabelled particles to be tracked in vivo and in the environment.
A Powder Processing Route to Polymer Composites
Authors: Giancola Giorgiana , Lehman Richard L
Published: January 2010

Powder processing of thermoplastic polymer composites offers multiple advantages for both micro- and nano-scale systems. A high degree of component homogenization is achieved prior to melt forming of the composite, thus minimizing degradation associated with extended thermal processing at high shear. Polymer blends can be prepared that would otherwise not be possible due to thermodynamic incompatibility. Initial evaluation of this concept was conducted by processing PMMA and HDPE micron size powder prepared by emulsion polymerization. Spherical silica particles of comparable size (mean size = 5 μm) were added to a 30/60 PMMA/HDPE blend at the 10 volume percent concentration and mixed in an aqueous medium prior to drying and extrusion. Analysis of optical and electron microscope images of the raw mixture shows good homogeneity and distribution of the small inorganic particles around the larger matrix phase particles by the process of interstitial filling. The melt-processed composite was observed by SEM and consisted of a three-phase system of dispersed silica and PMMA particles in a HDPE matrix.
Effect of Humidity on Dielectric Charging Process in Electrostatic Capacitive RF MEMS Switches Based on Kelvin Probe Force Microscopy Surface Potential Measurements
Authors: Zaghloul Usama , Papaioannou George J. , Coccetti Fabio , Pons Patrick , Plana Robert
Published: January 2010

In this article we investigate the effect of relative humidity on dielectric charging/discharging processes in electrostatically actuated MEMS devices. The assessment procedure is based on surface potential measurements using Kelvin Probe Force Microscopy (KPFM) and it targets in this specific work PECVD silicon nitride films in view of application in electrostatic capacitive RF MEMS switches. Charges have been injected through the AFM tip and the induced surface potential has been measured under different relative humidity levels. The impact of the charge injection duration and the bias level as well as bias polarity applied during the charge injection step, have been explored. Finally, the effect of the dielectric film thickness under different relative humidity levels has been assessed through depositing SiN films with different thicknesses.
Addressing Diversity in STEM Education: Authenticity and Integration
Authors: Goodchild Fiona M. , Aguirre Maria O.
Published: January 2010

This talk will reflect on the challenges of designing educational opportunities that broaden diversity in the ranks of future scientists and engineers. The speaker, who is Education Director at the California Nanosystems Institute (CNSI) at the University of California, Santa Barbara, will report on the design and evaluation of a program that integrates academic, career and social components to engage a community of undergraduates, graduate mentors and research faculty at UCSB. The program builds on key practices such as academic mentorship, community networking and early undergraduate research. Evaluation of this program, Expanding Pathways to Science, Engineering and Mathematics (EPSEM) indicates that it has been successful in recruiting and retaining students from under-represented (URM) groups into science, technology, engineering and math disciplines (STEM disciplines).
Hierarchically Structured Conjugated Polymers
Authors: Frauenrath Holger
Published: January 2010

Functional carbonaceous materials, organic electronic materials, and polymer materials which "speak the language" of biomaterials in their propensity for hierarchical structure formation play a central role in current materials science research. In this context, we prepared hierarchically structured conjugated polymers from diacetylene macromonomers based on β-sheet-forming oligopeptide-polymer conjugates as supramolecular building blocks. The monomers gave rise to supramolecular polymers with a finite number of strands, a uniform diameter of a few nanometers, and defined superstructures. These were then converted into conjugated polymers under retention of their hierarchical structures, leading to poly(diacetylene)s with multiple-helical quaternary structures and a rich folding behavior. The diacetylene macromonomers served as a model system to improve our understanding of how to use hydrogen-bonding sites in order to control the placement of reactive molecular precursors for hierarchically structured organic materials.
Text Mapping Plus: Improving Comprehension Through Supported Retellings
Authors: Lapp Diane , Fisher Douglas , Johnson Kelly
Published: January 2010

Modeled in this column is the teaching of a text mapping routine that supports students reading and remembering the salient features of the text. The authors renamed the story mapping technique text mapping plus because they found that as students added relational words and graphics to their maps their retells of both fiction and nonnarrative were fuller, more accurate, and shared with greater confidence.

تمثّل في هذا العمود تدريس نظام مسح النص الذي يدعم قراءة الطلاب وتذكرهم بمعالم النص البارزة. وقد ألقى المؤلفون تسمية جديدة على نظام مسح النص إنما هي مسح النص الزائد لأنهم وجدوا أن كلما أضاف الطلاب كلمات وصوراً متعلقة بمسحهم كلما زادت إعادة حكايتهم بالنسبة للروايات الخيالية وغير السردية في العرض والدقة والتقديم بثقة أكبر.

在本期专栏里所介绍的教学模型，是有关教授建构文本地图的例行程序，以支援学生读懂文本及记忆文本中显著的特色。作者把建构故事地图的技巧，重新命名为「文本地图加强版」，因为作者发现当学生建构文本地图时，他们会加进相关的词汇及绘图，会更完整、更准确地复述小说故事及非叙事文本的内容，并会更有信心地与人分享文本的内容。

On modélise dans cette rubrique l'enseignement d'une procédure de configuration de texte en vue de renforcer la lecture et la mémorisation par les élèves des caractéristiques majeures d'un texte. Les auteurs ont donné un nouveau nom à la technique de configuration d'une histoire et parlent maintenant de configuration de texte plus parce qu'ils ont trouvé que quand les élèves ajoutent des mots de relation et des graphiques à leur configuration, leur répétition de ce qui est narratif et de ce qui ne l'est pas est plus complète, plus précise, et est apporté avec plus de confiance.

В этом выпуске рубрики представлена модель, по которой школьников можно обучить составлению “карты текста”. Данный метод эффективен для чтения и запоминания существенных моментов прочитанного. Авторы назвали свою модификацию метода “карта плюс”, поскольку выяснили, что когда учащиеся добавляют к составляемым картам дополнительные, связанные с текстом слова и изображения, они пересказывают как художественный, так и нехудожественный текст более уверенно, полно и подробно.

Se modela en esta columna cómo enseñar a hacer mapas para ayudar al estudiante a recordar los aspectos más importantes de un texto. Los autores llamaron esta técnica topografía textual plus porque encontraron que, a medida que los estudiantes añadían a sus mapas palabras y gráficos relacionados, podían volver a contar tanto las narraciones ficticias como las no ficticias más detalladamente, con más fidelidad, y con más seguridad en sí mismos.
How Do We Teach Reading as a Strategic, Decision‐Making Process?
Authors: Ellery Valerie
Published: January 2010

The following activities, Detail/Retell and Collaborate and Elaborate, adapted from the new IRA book Creating Strategic Readers (second edition), highlight how two of the five essential reading components are used in a comprehensive literacy classroom to create strategic readers. The activities also demonstrate how to engage and motivate students and meet their diverse needs.
Histology-specific risks in testicular cancer in immigrants to Sweden
Authors: Hemminki Kari , Mousavi Seyed Mohsen , Brandt Andreas , Ji Jianguang , Sundquist Jan
Published: January 2010

The changes of cancer incidence upon immigration have been used as an estimator of environmental influence on cancer risk. The previous immigrant studies have indicated that the origins of testicular cancer are at an early age in life, probably in the intrauterine period. We wanted to reexamine the critical periods on histology-specific testicular cancer in sons of immigrants to Sweden. We used the nationwide Swedish Family-Cancer Database to calculate standardized incidence ratios (SIRs) for testicular cancer in sons of parents immigrating to Sweden from low- and high-risk countries compared with the native Swedes. Among the large immigrant groups, the SIRs for sons of two Finnish and Asian parents were decreased if the sons were born outside Sweden. The sons of a Danish immigrant couple showed an increased risk of testicular cancer. The changes in SIR were most systematic for seminoma. The present patterns of testicular cancer risk among sons of immigrants point to the early environmental risk factors, which influence the risk probably after the intrauterine period. These factors appear to influence seminoma risk in a more enduring way than they influence non-seminoma.
Estradiol selectively stimulates endothelial prostacyclin production through estrogen receptor-α
Authors: Sobrino Agua , Oviedo Pilar J , Novella Susana , Laguna-Fernandez Andrés , Bueno Carlos , García-Pérez Miguel Angel , Tarín Juan J , Cano Antonio , Hermenegildo Carlos
Published: January 2010

Estradiol (E2) acts on the endothelium to promote vasodilatation through the release of several compounds, including prostanoids, which are products of arachidonic acid metabolism. Among these, prostacyclin (PGI2) and thromboxane A2 (TXA2) exert opposite effects on vascular tone. The role of different estrogen receptors (ERs) in the PGI2/TXA2 balance, however, has not been fully elucidated. Our study sought to uncover whether E2 enhances basal production of PGI2 or TXA2 in cultured human umbilical vein endothelial cells (HUVECs), to analyze the enzymatic mechanisms involved, and to evaluate the different roles of both types of ERs (ERα and ERβ). HUVECs were exposed to E2, selective ERα (1,3,5-tris(4-hydroxyphenyl)-4-propyl-1h-pyrazole, PPT) or ERβ (diarylpropionitrile, DPN) agonists and antagonists (unspecific: ICI 182 780; specific for ERα: methyl-piperidino-pyrazole, MPP). PGI2 and TXA2 production was measured by ELISA. Expression of phospholipases, cyclooxygenases (COX-1 and COX-2), PGI2 synthase (PGIS), and thromboxane synthase (TXAS) was analyzed by western blot and quantitative RT-PCR. E2 (1–100 nM) dose dependently increased PGI2 production (up to 50%), without affecting TXA2 production. COX-1 and PGIS protein and gene expressions were increased, whereas COX-2, phospholipases, and TXAS expression remained unaltered. All these effects were mediated through ERα, since they were produced not only in the presence of E2, but also in that of PPT, while they were abolished in the presence of MPP. In conclusion, E2, acting through ERα, up-regulates COX-1 and PGIS expression, thus directing prostanoid balance toward increased PGI2 production.
Field investigation of base resistance of pipe piles in clay
Authors: Doherty P. , Gavin K. , Gallagher D.
Published: January 2010

This paper presents the results of a series of field tests performed to study the effect of soil plugging during installation on the base resistance developed by an open-ended (pipe) pile in clay. Three instrumented pipe piles were installed in soft clay, and the installation resistance and soil plug development were recorded. The tests revealed that the annular base resistance was equal to the cone penetration test qc resistance and was independent of the soil plug development. In contrast, the soil plug resistance increased from a minimum when the pile was fully coring to a maximum when the pile was fully plugged. A simple expression is proposed that links the plug resistance to the cone penetration test qc value at the specified depth and the incremental filling ratio value developed during installation. This expression is shown to provide reasonable estimates of the plug resistance developed by a large-diameter pipe pile driven into stiff to hard clay in the North Sea. The proposed relationship will be particularly useful for modelling the installation resistance of monopile foundations.
Shear strength properties of water treatment residues
Authors: O'Kelly B. C. , Quille M. E.
Published: January 2010

This paper presents the physical, standard Proctor compaction and shear strength properties of alum water treatment residues derived from the production of potable water at municipal works. In particular, the effects of catchment geology, chemical treatments at the municipal works, hardening phenomena and shearing rate on the constitutive and shear strength responses of these high-plasticity organic clays were studied. Slurry residues have low bulk and dry densities (0·96–1·13 and 0·21–0·36 t/m3 respectively) and low specific gravity of solids (1·83–1·99), and are highly compressible, although the consolidation rate is low. The dewatered residues have high values of effective angle of shearing resistance of 39–44°. Low concentrations of polyelectrolyte added to the residues altered the constitutive response (more elastic perfectly plastic, with shear failure occurring between 2% and 10% compressive strain): the undrained shear strength was enhanced by 10–20% and the effective angle of shearing resistance increased by 2°. Alum residues derived from peaty catchments were found to have marginally higher undrained shear strengths than those from a limestone-bedrock catchment. Recommendations are made regarding adequate dewatering of the slurry residue and the efficient landfill disposal of the pressed residue cake.
Security of payment for Hong Kong construction industry
Authors: Cheng T. , Soo G. , Kumaraswamy M. , Jin W.
Published: January 2010

In Hong Kong, getting paid is not always easy and the construction industry stands as an illustration of how much effort may be needed to achieve this and how adverse impacts can escalate from payment problems. At the moment, many jurisdictions have adopted some form of legislation or practical measures to enhance the ease and security of payment in the construction industry. Experience and insights from their operations provide guidance to Hong Kong for its way forward. By studying practices and feedback in other jurisdictions, this paper outlines and reviews the options and alternatives implemented for securing payment in the construction industry in Hong Kong. In addition, it also seeks to appraise their respective practicability for Hong Kong and highlight those areas to be considered if they are to be adopted or adapted for use in the Hong Kong construction industry. The ultimate aim is to provide an objective, balanced and reasoned overview for further study and discussion among stakeholders in the Hong Kong construction industry when moving forward. This is not intended to be an exhaustive review of all means adopted to achieve security of payment but aims to discuss those methods which are more likely to be suitable to be adopted in Hong Kong in the light of the circumstances and environment prevailing there. Furthermore, this study did not investigate the many modes of procurement that are available and which may address the concern of security of payment but focuses on the traditional form of contracts in use in Hong Kong. Public–private partnerships or private finance initiatives which would call for different discussions are not covered.
Geomagnetic Referencing Service - A Viable Alternative for Accurate Wellbore Surveying
Authors: Poedjono Benny , Adly Essam , Terpening Mike , Li Xiong
Published: January 2010

Wellbore positioning is a major challenge in eastern Canada because of the extensive faults in the Jeanne d'Arc basin. Accurate well placement is vital to the success of hydrocarbon production; accurate surveys are required in real time to drill 3D trajectories that penetrate multiple small geological targets and avoid costly subsurface collisions with adjacent wellbores.

Magnetic surveying has become increasingly accurate and now provides a cost-effective alternative to gyroscopic surveys in real-time drilling applications. Magnetic tools are subject to two main sources of error: variations in the local magnetic field and interference from magnetized elements in the drillstring. New techniques for identifying and compensating for these errors involve a better understanding of the natural variations in the earth's magnetic field, and new methods of mapping local variations improve magnetic modeling.

A key innovation is the ability to create an accurate and robust crustal model and integrate real-time diurnal measurements from nearby magnetic observatories. The addition of observatory data that improves positional uncertainty has made magnetic surveying a viable option, even at higher latitudes where more extreme variations in the local magnetic field would otherwise induce unacceptable positioning errors. Geomagnetic referencing services now offer a multitiered approach to achieve the requisite degree of positional accuracy within the economic restraints of a given drilling program.

Geomagnetic referencing can produce significant savings in overall project costs by providing accurate, real-time data on well position while corrections to trajectory are still possible. Real-time azimuth control can prevent the costly sidetracks that are often required when only a postdrilled survey is performed and reveals that the well has missed its target. Geomagnetic referencing also eliminates the cost of extra rig time required to run an accurate postdrilled gyroscopic survey, which can be a significant benefit when budget restraints are critical.
McConnell Taping Shifts the Patella Inferiorly in Patients With Patellofemoral Pain: A Dynamic Magnetic Resonance Imaging Study
Authors: Derasari Aditya , Brindle Timothy J. , Alter Katharine E. , Sheehan Frances T.
Published: January 2010

Background

Patellar taping is widely used clinically to treat patients with patellofemoral pain syndrome (PFPS). Although patellar taping has been demonstrated to reduce patellofemoral pain in patients with PFPS, the kinematic source for this pain reduction has not been identified.

Objective

The purpose of this study was to quantify the changes in the 6-degrees-of-freedom patellofemoral kinematics due to taping in patients with PFPS.

Design

A within-subject design and a sample of convenience were used.

Participants

Fourteen volunteers (19 knees) who were diagnosed with patellofemoral pain that was present for a year or longer were included. Each knee had to meet at least 1 of the following inclusion criteria: Q-angle of ≥15 degrees, a positive apprehension test, patellar lateral hypermobility (≥10 mm), or a positive “J sign.”

Methods

Each knee underwent 2 randomly ordered testing conditions (untaped and taped). A full fast-phase contrast (PC) magnetic resonance image set was acquired for each condition while the participants volitionally extended and flexed their knee. Three-dimensional displacements and rotations were calculated through integration of the fast-PC velocity data. Statistical comparisons between baseline patellofemoral kinematics and the change in kinematics due to taping were performed using a 2-tailed paired Student t test. Correlations between baseline patellofemoral kinematics and the change in kinematics due to taping also were quantified.

Results

Patellar taping resulted in a significant patellofemoral inferior shift. The strongest correlation existed between the change in lateral-medial displacement with taping and baseline (r=−.60).

Conclusions

The inferior shift in patellar displacement with taping partially explains the previously documented decrease in pain due to increases in contact area. The lack of alteration in 5 of the 6 kinematic variables with taping may have been due to the fact that post-taping kinematic alterations are sensitive to the baseline kinematic values.
Interhemispheric Modulation Induced by Cortical Stimulation and Motor Training
Authors: Williams Julie A. , Pascual-Leone Alvaro , Fregni Felipe
Published: January 2010

Background

Interhemispheric inhibition might be a beneficial cortico-cortical interaction, but also might be maladaptive in people with neurological disorders. One recently revisited technique that has been shown to be effective in improving motor function in people with stroke using interhemispheric modulation is transcranial direct current stimulation (tDCS).

Objective

The aim of this study was to investigate the effects of tDCS combined with unilateral motor training with contralateral hand restraint on interhemispheric inhibition between the dominant and nondominant hemispheres of the brain and on motor performance in participants who were healthy.

Design

This was a double-blind, prospective, single-center study with participants who were healthy.

Methods

Twenty participants who were healthy were randomly assigned to receive either active or sham tDCS of the primary motor cortex (M1) bilaterally combined with unilateral motor training and contralateral hand restraint. A blinded rater assessed motor function and cortical excitability, including assessment of transcallosal inhibition (TCI).

Results

There was a larger increase in motor performance in the nondominant hand for the active tDCS group compared with the sham tDCS group. In addition, a decrease in cortical excitability in the dominant hemisphere and a decrease in TCI from the dominant to nondominant hemisphere were observed for the active tDCS group only. The TCI decrease in the active tDCS group was correlated with motor performance improvement for the nondominant hand.

Limitations

Limitations of this study included missing the effect of intracortical inhibition due to a floor effect, not using the optimal tDCS montage, and not being able to assess the effects of other variables such as gender due to the small sample size.

Conclusions

The results indicate that tDCS enhances the effects of unilateral motor training and contralateral hand restraint on motor function, and this benefit is associated with a different mechanism of action characterized by bihemispheric modulation in which TCI from the dominant to the nondominant hemisphere is decreased. Transcranial direct current stimulation might be a useful tool to enhance the motor effects of constraint-induced movement therapy.
Rapid closure technique in decompressive craniectomy
Authors: Güresir Erdem , Vatter Hartmut , Schuss Patrick , Oszvald Ági , Raabe Andreas , Seifert Volker , Beck Jürgen
Published: January 2010

Object

The object of this study was to describe the rapid closure technique in decompressive craniectomy without duraplasty and its use in a large cohort of consecutive patients.

Methods

Between 1999 and 2008, supratentorial rapid closure decompressive craniectomy (RCDC) was performed 341 times in 318 patients at the authors' institution. Cases were stratified as 1) traumatic brain injury, 2) subarachnoid hemorrhage, 3) intracerebral hemorrhage, 4) cerebral infarction, and 5) other. A large bone flap was removed and the dura mater was opened in a stellate fashion. Duraplasty was not performed—that is, the dura was not sutured, and a dural substitute was neither sutured in nor layed on. The dura and exposed brain tissue were covered with hemostyptic material (Surgicel). Surgical time and complications of this procedure including follow-up (> 6 months) were recorded. After 3–6 months cranioplasty was performed, and, again, surgical time and any complications were recorded.

Results

Rapid closure decompressive craniectomy was feasible in all cases. Complications included superficial wound healing disturbance (3.5% of procedures), abscess (2.6%) and CSF fistula (0.6%); the mean surgical time (± SD) was 69 ± 20 minutes. Cranioplasty was performed in 196 cases; the mean interval (± SD) from craniectomy to cranioplasty was 118 ± 40 days. Complications of cranioplasty included epidural hematoma (4.1%), abscess (2.6%), wound healing disturbance (6.1%), and CSF fistula (1%).

Compared with the results reported in the literature for decompressive craniectomy with duraplasty followed by cranioplasty, there were no significant differences in the frequency of complications. However, surgical time for RCDC was significantly shorter (69 ± 20 vs 129 ± 43 minutes, p < 0.0001).

Conclusions

The present analysis of the largest series reported to date reveals that the rapid closure technique is feasible and safe in decompressive craniectomy. The surgical time is significantly shorter without increased complication rates or additional complications. Cranioplasty after a RCDC procedure was also feasible, fast, safe and not impaired by the RCDC technique.
Technique for the localization of intracranially implanted electrodes
Authors: Darcey Terrance M. , Roberts David W.
Published: January 2010

Object

The anatomical localization of electrodes in the human brain is important for the interpretation of pathophysiological (epileptifom spikes, seizures) and functional data (stimulation mapping, evoked potentials). Electroencephalography and evoked potentials are volume-conducted field effects that are most easily interpreted with knowledge of the location and topology of adjacent structures, and brain stimulation techniques produce current fields whose effects are highly dependent on the geometry of electrode assemblies in relation to adjacent structures. In this paper, the authors describe a straightforward method for implanted electrode localization, and detail their experience to date with the technique.

Methods

The described method is based on the coregistration of preoperative MR imaging studies with postimplant CT scans by using standard mutual information optimization of rigid body transformation of the CT to the MR image. Fused images of the MR and thresholded CT images are derived, and electrodes are visualized using various standard computer projections, renderings, and measurement tools.

Results

The authors have successfully used the described method over an extended period to localize electrode contacts in intracranial implants for seizure localization, and in long-term implants for movement disorders and seizure control. The accuracy of localization is very good, although it is dependent on image quality and possible brain shift between acquisition of the CT and MR images.

Conclusions

This method is easily implemented and is useful for a wide variety of clinical and research applications. It is a straightforward process to extend it to additional image modalities that are emerging for surgical planning and image guidance.
Role of extracellular glutamate measured by cerebral microdialysis in severe traumatic brain injury
Authors: Chamoun Roukoz , Suki Dima , Gopinath Shankar P. , Goodman J. Clay , Robertson Claudia
Published: January 2010

Object

Authors of several studies have implied a key role of glutamate, an excitatory amino acid, in the pathophysiology of traumatic brain injury (TBI). However, the place of glutamate measurement in clinical practice and its impact on the management of TBI has yet to be elucidated. The authors' objective in the present study was to evaluate glutamate levels in TBI, analyzing the factors affecting them and determining their prognostic value.

Methods

A prospective study of patients with severe TBI was conducted with an inclusion criterion of a Glasgow Coma Scale score ≤ 8 within 48 hours of injury. Invasive monitoring included intracranial pressure measurements, brain tissue PO2, jugular venous O2 saturation, and cerebral microdialysis. Patients received standard care including mass evacuation when indicated and treatment of elevated intracranial pressure values. Demographic data, CT findings, and outcome at 6 months of follow-up were recorded.

Results

One hundred sixty-five patients were included in the study. Initially high glutamate values were predictive of a poor outcome. The mortality rate was 30.3% among patients with glutamate levels > 20 μmol/L, compared with 18% among those with levels ≤ 20 μmol/L.

Two general patterns were recognized: Pattern 1, glutamate levels tended to normalize over the monitoring period (120 hours); and Pattern 2, glutamate levels tended to increase with time or remain abnormally elevated. Patients showing Pattern 1 had a lower mortality rate (17.1 vs 39.6%) and a better 6-month functional outcome among survivors (41.2 vs 20.7%).

Conclusions

Glutamate levels measured by microdialysis appear to have an important role in TBI. Data in this study suggest that glutamate levels are correlated with the mortality rate and 6-month functional outcome.
Safety of carotid endarterectomy while on clopidogrel (Plavix)
Authors: Wait Scott D. , Abla Adib A. , Killory Brendan D. , Starke Robert M. , Spetzler Robert F. , Nakaji Peter
Published: January 2010

Object

Many patients undergoing carotid endarterectomy (CEA) regularly take clopidogrel, a permanent platelet inhibitor. The authors sought to determine whether taking clopidogrel in the period before CEA leads to more bleeding or other complications.

Methods

The authors performed a retrospective, institutional review board–approved review of 182 consecutive patients who underwent CEA. Clinical, radiographic, and surgical data were gleaned from hospital and clinic records. Analysis was based on the presence or absence of clopidogrel in patients undergoing CEA and was performed twice by considering clopidogrel use within 8 days and within 5 days of surgery to define the groups.

Results

Taking clopidogrel within 8 days before surgery resulted in no statistical increase in any measure of morbidity or death. Taking clopidogrel within 5 days was associated with a small but significant increase in operative blood loss and conservatively managed postoperative neck swelling. No measure of permanent morbidity or death was increased in either clopidogrel group.

Conclusions

Findings in this study support the safety of preoperative clopidogrel in patients undergoing CEA.
Oketani Lactation Management: A New Method to Augment Breast Milk
Authors: Kabir Nazeen , Tasnim Saria
Published: January 2010

DOI:10.3329/jbcps.v27i3.4293 J Bangladesh Coll Phys Surg 2009; 27: 155-159
Epidemiological Profile of Pandemic Influenza A (H1N1) 2009 at Dhaka Medical College Hospital
Authors: Islam Quazi Tarikul , Kahhar Azizul , Arif Syed Mohammad , Kabir Ahmedul , Arif Khan Mohammed , Kibria Golam , Saha Narayan Chandra , Siddiqui Md Mahmudur Rahman , Mahbub Md Shahriar , Ahasan HAM Nazmul , Quader Bazle
Published: January 2010

The first case of 2009 pandemic influenza A (H1N1) virus infection in Bangladesh was documented on June 18. Subsequently, persons with suspected cases of infection and contacts of those with suspected infection were tested. Individuals in whom infection was confirmed were hospitalized and quarantined, and some of them were closely observed for the purpose of investigating the nature and duration of the disease. In Dhaka Medical College Hospital, there were 28 admitted patients in flu ward and 2335 registered suspected H1N1 influenza cases attended in flue corner but 833 highly suspected cases were recorded in case record form. We describe the epidemiological characteristics of 28 indoor (flu ward) and 833 outdoor (flu corner) patients. Most of them were in between 20 to 30 years age group. Among 833 outdoor patients 611(73.34%) were male and 222(26.65%) were female. 354 (42.49%) patients were student, 195 (23.40%) were service holder. No patients (indoor) had any serious underlying medical conditions. Keywords: Pandemic influenza A (H1N1), Dhaka Medical College Hospital, Bangladesh, epidemiology. DOI:10.3329/jom.v11i1.4259 J Medicine 2010: 11: 3-6
Psychiatric Morbidity of Suicide Attempt Patients Requiring ICU Intervention
Authors: Qusar MMA Shalahuddin , Morshed Nahid Mahjabin , Kader Md Abdul , Azad Md Abul Kalam , Uddin Md Alal , Shaikh Muhammad Abdul Kayum
Published: January 2010

This study was carried out in a private Intensive Care Unit (ICU) to assess the psychiatric morbidities and major psychiatric problems in patients requiring ICU. The most common psychiatric diagnosis was found to be Depressive disorder followed by attention seeking behavior. Chemicals (organophosphorous, kerosene and other medicine) were the most frequent agent used among suicide attempt patients. Keyword: Deliberate self harm, intensive care, mood disorders DOI:10.3329/jom.v11i1.4260 J Medicine 2010: 11: 7-11
Plasma BNP (B-Type Natriuretic Peptide) and Heart Failure: A Case-Control Study
Authors: Sultana Parvin , Hoque Md Mozammel , Shafiullah Samina
Published: January 2010

Background: Accurate diagnosis of heart failure (HF) is essential for its proper management and logical drug therapy to reduce morbidity and mortality. In this perspective, researchers are in search of a good biomarker as complementary to the clinical parameters to improve the performance of HF diagnosis. B-type natriuretic peptide (BNP) secreted by cardiac ventricles in HF has emerged as a new promising biomarker in this regard. Objective: Evaluation of plasma BNP concentration in HF cases. Methods: In a hospital based case-control study, 100 HF cases and 80 age and sex matched control subjects without HF were enrolled by non random sampling. Plasma BNP was measured in all study subjects and then compared between cases and controls. Results: Median plasma BNP concentration in HF (446.5pg/ml, range 16.8-4000pg/ml) found to be significantly high compared to that in control subjects (69.5pg/ml, range 0.6-627.5pg/ml). Conclusion: In HF patients, plasma BNP is raised significantly. So it can be a promising biomarker for diagnosis of HF. Keywords: B-type natriuretic peptide, heart failure DOI:10.3329/jom.v11i1.4268 J Medicine 2010: 11: 46-50
Antivenom for Snake Bite: Critical Supply in Health Care Settings
Authors: Amin Md Robed
Published: January 2010

Poisonous snake bite is common in Bangladesh, especially on the countryside. Often fatality occurs in these cases due to lack of anti-snake venom supply in rural areas. Health professionals are sometimes found wanting in skills and knowledge in dealing with such cases. Critical care support is essential in every case of snake bite which, unfortunately, is underdeveloped in our country. We are in urgent need of locally produced anti-snake venom to ensure availability of this life-saving drug in all parts of the country. Keywords: Anti-snake venom, Bangladesh   DOI:10.3329/jom.v11i1.4274 J Medicine 2010: 11: 57-59
Disseminated Histoplasmosis
Authors: Mahbub Md Shahriar , Ahasan HAM Nazmul , Miah Md Titu , Alam Md Billal , Gupta Ratan Das , Arif Khan Mohammad , Hasnain Muntasir
Published: January 2010

A case of disseminated histoplasmosis in a 56-year-old apparently healthy male without any history of travel to endemic zone is described. The patient presented with fever with cough, respiratory distress and disorientation. Physical findings include fever, shortness of breath, reduced level of consciousness and hypotension. Diagnosis was confirmed by presence of Histoplasma capsulatum in bone marrow aspirate. This report illustrates the importance of recognizing the possibility of histoplasmosis in Bangladesh where mimickers of histoplasmosis like pulmonary tuberculosis and visceral leishmaniasis are extremely common. Keywords: Histoplasmosis, endemic mycoses, disseminated histoplasmosis, Histoplasma capsulatum, Bangladesh DOI:10.3329/jom.v11i1.4278 J Medicine 2010: 11: 70-73
Evans Syndrome
Authors: Kabir Ahmedul , Banik Jayanta , Gupta Ratan Das , Amin Robed , Faisal AM Wasiq , Islam ASM Mafidul , Kamal Mostofa , Paul Pinaki , Chowdhury Faizul Islam , Parveen Hasna Hena
Published: January 2010

Evans' syndrome is a rare autoimmune disorder in which the body makes antibodies that destroy the red blood cells, platelets and white blood cells. Patients are diagnosed with thrombocytopenia and Coombs' positive haemolytic anaemia and have no other known underlying aetiology. We report two cases of autoimmune haemolytic anaemia (AIHA) associated with immune thrombocytopenia which is known as Evans's syndrome. In these patient there were clinical evidence of haemolysis, serum bilirubin was elevated, blood film showed anaemia with trrombocytopenia but no spherocytosis. Immunosuppression was achieved with steroid. We would like to highlight that a negative Coomb's test is now often interpreted as absence of autoantibodies, but it is more or less preclusive for the diagnosis of AIHA. Keywords: Evan's Syndrome, autoimmune haemolytic anaemia DOI:10.3329/jom.v11i1.4280 J Medicine 2010: 11: 78-82
Imaging Negative Parathyroid Adenoma
Authors: Kader Md Abdul , Azad Md Abdul Kalam , Rahaman Md Ferdous Ur , Khan Abed Hussain , Chowdhury MA Jalil , Aziz Md Mohibul , Karim Enayet
Published: January 2010

Primary hyperparathyroidism typically presents with skeletal and renal manifestations. In most (80-85%) cases, the cause is a single parathyroid adenoma. We present a case of 36-year-old lady of primary hyperparathyroidism presented with multiple fractures, nephrolithiasis, and nephrocalcinosis. All of the imaging techniques to localize the cause were negative. She underwent surgical neck exploration with detection of left parathyroid adenoma. Her post-operative period was uneventful with significant clinical and biochemical improvement. Keywords: Primary hyperparathyroidism, hyperparathyroidism, hypercalcemia, parathyroid imaging. DOI:10.3329/jom.v11i1.4281 J Medicine 2010: 11: 83-85
Synthesis of (3R,5R)-harzialactone A and its (3R,5S)-isomer
Authors: Sabitha Gowravaram , Srinivas Rangavajjula , Das Sukant K , Yadav Jhillu S
Published: January 2010

The total synthesis of (3R,5R)-harzialactone A (1) and its (3R,5S)-isomer (2) is described. Epoxide opening with thioacetal and diastereoselective reductions are used as key reactions.
Surface Fluxes and Tropical Intraseasonal Variability: a Reassessment
Authors: Sobel Adam H. , Maloney Eric D. , Bellon Gilles , Frierson Dargan M.
Published: January 2010

The authors argue that interactive feedbacks involving surface moist enthalpy fluxes, both turbulent and radiative, are important to the dynamics of tropical intraseasonal variability. Evidence in favor of this hypothesis includes the observed spatial distribution of intraseasonal variance in precipitation and outgoing longwave radiation, the observed relationship between intraseasonal latent heat flux and precipitation anomalies in regions where intraseasonal variability is strong, and sensitivity experiments performed with a small number of general circulation and idealized models. The authors argue that it would be useful to assess the importance of surface fluxes to intraseasonal variability in a larger number of comprehensive numerical models.
Clinical and Serologic Factors Associated with Lupus Pleuritis
Authors: MITTOO SHIKHA , GELBER ALLAN C. , HITCHON CAROL A. , SILVERMAN EARL D. , POPE JANET E. , FORTIN PAUL R. , PINEAU CHRISTIAN , SMITH C. DOUGLAS , ARBILLAGA HECTOR , GLADMAN DAFNA D. , UROWITZ MURRAY B. , ZUMMER MICHEL , CLARKE ANN E. , BERNATSKY SASHA , HUDSON MARIE , TUCKER LORI B. , PETTY ROSS E. , PESCHKEN CHRISTINE A.
Published: January 2010

Objective.

Pleuritis is a common manifestation and independent predictor of mortality in systemic lupus erythematosus (SLE). We examined the prevalence of pleuritis and factors associated with pleuritis in a multicenter Canadian SLE cohort.

Methods.

We studied consecutive adults satisfying the American College of Rheumatology (ACR) classification criteria for SLE who had a completed Systemic Lupus International Collaborating Clinics/ACR Damage Index (SDI) score, at least 1 evaluable extractable nuclear antigen assay, and either a SLE Disease Activity Index (SLEDAI) or a SLE Activity Measure score. Pleuritis was defined as having pleuritis by satisfying the ACR criteria or the SLEDAI. Factors related to pleuritis were examined using univariate and multivariate logistic regression.

Results.

In our cohort of 876 patients, 91% were women, 65% Caucasian, mean age (± SD) was 46.8 ± 13.5 years, and disease duration at study entry was 12.1 ± 9.9 years; the prevalence of pleuritis was 34% (n = 296). Notably, greater disease duration (p = 0.002), higher SDI score (p ≤ 0.0001), age at SLE diagnosis (p = 0.009), and anti-Sm (p = 0.002) and anti-RNP (p = 0.002) seropositivity were significantly associated with pleuritis. In multivariate analysis with adjustment for disease duration, age at diagnosis, and SDI score, concomitant seropositivity for RNP and Sm were related to a nearly 2-fold greater prevalence of pleuritis (OR 1.98, 95% CI 1.31–2.82).

Conclusion.

Pleuritis occurred in one-third of this Canadian cohort. Concomitant Sm and RNP seropositivity, greater cumulative damage, longer disease duration, and younger age at SLE disease onset were related to a higher rate of SLE pleural disease.
Expression of High Mobility Group Box Chromosomal Protein 1 and Its Modulating Effects on Downstream Cytokines in Systemic Lupus Erythematosus
Authors: LI JIE , XIE HONGFU , WEN TING , LIU HONGBO , ZHU WU , CHEN XIANG
Published: January 2010

Objective.

To compare the expression of high mobility group box chromosomal protein 1 (HMGB1) and the modulating effects on its downstream cytokines in patients with systemic lupus erythematosus (SLE) and healthy controls.

Methods.

HMGB1 concentrations in serum from SLE patients and controls were measured by immunoblot analysis. HMGB1 messenger RNA (mRNA) expression in peripheral blood mononuclear cells (PBMC) was detected by real-time reverse transcription–polymerase chain reaction. Immunofluorescence assay was employed to examine the translocation of HMGB1 in monocytes after endotoxin stimulation. Release of tumor necrosis factor-α (TNF-α) and interleukin 6 (IL-6) by PBMC after rHMGB1 stimulation was also measured.

Results.

Serum HMGB1 levels and HMGB1 mRNA expressions in PBMC were elevated in SLE patients compared with controls. A positive correlation was demonstrated between HMGB1 concentrations and SLE Disease Activity Index. There was an inverse correlation between HMGB1 levels and C4 and C3 concentrations in SLE patients. HMGB1 concentrations were higher in patients with vasculitis and myositis. Lipopolysaccharide stimulated a temporarily elevated release of HMGB1 in SLE patients compared with controls. The pattern and localization of HMGB1 staining in monocytes were similar in both groups. After stimulation with rHMGB1, TNF-α level decreased but IL-6 level increased in SLE patients compared with controls.

Conclusion.

Our findings suggest that increased serum levels of HMGB1 in SLE may be associated with lupus disease activity. The altered production of TNF-α and IL-6 in response to rHMGB1 stimulation may participate in the disruption of cytokine homeostasis in SLE.