bluuebunny/crossref_metadata_2025 huggingface dataset:
The Status of Acute Stroke Care in Saudi Arabia: An Urgent Call for Action!
Authors: Al Khathaami Ali M. , Algahtani Hussein , Alwabel Albaraa , Alosherey Nora , Kojan Suleiman , Aljumah Mohammed
Published: January 2011

Stroke care in Saudi Arabia lags behind developed countries with only one active stroke centre and seven centres providing thrombolysis out of >350 hospitals nationally; only two hospitals have a stroke team with implemented triaging pathways and beeper system. Via phone interview, we approached 83 neurologists and asked their opinion on stroke care practiced in Saudi Arabia. The study was approved by IRB. There are >350 hospitals in Saudi Arabia and only one centre has a stroke unit, and only seven provide thrombolysis. It is estimated that the number of cases treated with thrombolysis is 50/year for 24 million people. Overall, the neurologists indentified their priorities for improving care as: establishing stroke units; increase public awareness; and training health care providers and collaboration. The neurologists we interviewed view acute stroke care in Saudi Arabia as inadequate. This is an urgent call for actions to start organising nation-wide stroke care to close the existing huge evidence–practice gap.
DESTINY II: Decompressive Surgery for the Treatment of Malignant Infarction of the Middle Cerebral Artery II
Authors: Jüttler Eric , Bösel Julian , Amiri Hemasse , Schiller Petra , Limprecht Ronald , Hacke Werner , Unterberg Andreas ,   for the DESTINY II Study Group
Published: January 2011

Background

Patients with severe space-occupying – so-called malignant – middle cerebral artery infarcts have a poor prognosis even under maximum intensive care treatment. Randomised trials demonstrated that early hemicraniectomy reduces mortality from about 70% to 20% without increasing the risk of being very severely disabled. Hemicraniectomy increases the chance to survive completely independent more than fivefold and doubles the chance to survive at least partly independent. Only patients up to 60-years have been included in these trials. However, patients older than 60-years represent about 50% of all patients with malignant middle cerebral artery infarcts. Data from observational studies, suggesting that older patients may not profit from hemicraniectomy, are inconclusive, because these patients have generally been treated later and less aggressively. This leads to great uncertainty in everyday clinical practice.

Aims

To investigate the efficacy of early hemicraniectomy in patients older than 60-years with malignant MCA infarcts.

Materials & Methods

DEcompressive Surgery for the Treatment of malignant INfarction of the middle cerebral arterY II is a randomised controlled trial including patients 61-years and older with malignant middle cerebral artery infarcts. Patients are randomised to either maximum conservative treatment alone or in addition to early hemicraniectomy within 48 h after symptom onset. The trial uses a sequential design with a maximum number of 160 patients to be enrolled (ISRCTN 21702227).

Discussion

In the face of an ageing population, the potential benefit of hemicraniectomy in older patients is of major clinical relevance, but remains controversial.

Conclusion

The results of this trial are expected to directly influence decision making in these patients.
Primary Elbow Osteoarthritis: An Updated Review
Authors: Adla Deepthi Nandan , Stanley David
Published: January 2011

Primary elbow arthritis predominantly affects middle aged men undertaking heavy manual work. Patients present with pain and limited movement but may also complain of ulnar nerve sensory or motor symptoms. Radiographic features include osteophytes at the tip of the olecranon and coronoid processes, loose bodies, narrowing of the radiocapitellar joint space and thickening of the olecranon fossa membrane. Treatment options range from conservative management using oral analgaesics and non-steroidal anti-inflammatory drugs through to open debridement procedures, arthroscopy and occasionaly in selected patients total elbow arthroplasty.
Dynamic Splint for the Treatment of Stiff Elbow
Authors: Gallucci Gerardo L. , Boretto Jorge G. , Dávalos María A. , Donndorff Agustín , Alfie Verónica A. , De Carli Pablo
Published: January 2011

Background

The purpose of this paper is to retrospectively evaluate the results of the treatment of elbow stiffness with the use of dynamic splints.

Methods

We included 17 patients with stable and congruent joints, with a range of motion of 100 degrees or less who had not responded to the rehabilitation program. Average previous mobility was 108–42 degrees, with a total arc of 66 degrees. The splints consist of an articulated brace with springs. On average their use began 94 days after surgery or trauma and continued for 86 days. Statistical analysis was performed. Average follow-up was 18 months.

Results

Postoperative mobility was 126–19 degrees, with a total arc of 107 degrees. Motion increased an average of 41 degrees. Six patients failed to recover a functional arc of motion.

Conclusion

Our results suggest that dynamic splints are useful in the treatment of elbow stiffness. We achieved an average improvement of 41° in the arc of motion, which in many cases has rendered arthrolysis unnecessary. Tailoring the splint to the individual patient is very important since its usage must be prolonged in order to achieve plastic deformity through the principle of progressive stretching.
Scapulothoracic Fusion for Fascio-Scapulo-Humeral Dystrophy
Authors: Alshameeri Zeiad A. , Garg Sunil , Wallace W. Angus
Published: January 2011

Background

Scapulothoracic (ST) fusion has been recommended for suitable patients suffering from FacioScapuloHumeral Dystrophy (FSHD). It helps in creating a fulcrum for the deltoid and prevents winging of the scapula during flexion and abduction of the arm, thus improving activities of daily living. We present here an overview of the techniques used and the results of 9 ST fusion carried out at our department.

Method

The scapula is fixed to the underlying rips using Luque wires around the 2nd to 6th ribs, then passed through the medial border of the scapula, then through an 8 hole semi tubular plate placed over the dorsal aspect of the whole medial border of the scapula. After which the Luque wires are tied firmly, locking the scapula onto the chest wall. Morsellised bone allograft is placed between the scapula and the ribs before tightening the wires.

Results

In total 9 ST fusions were carried out. No Intra-operative complications occurred but 2 patients developed haemothoraces post-operatively, one resolved with chest drain and one needed thoracotomy. Late complications included one scapula fracture (subsequently internally fixed), one frozen shoulder (resolved with physiotherapy) and one protruding plate (subsequently removed). An average of 40 degrees of additional abduction was achieved and overall good patients satisfaction.
Exposure of Uninfected Poultry Farms to HPAI (H7N7) Virus by Professionals During Outbreak Control Activities
Authors: te Beest D. E. , Stegeman J. A. , Mulder Y. M. , van Boven M. , Koopmans M. P. G.
Published: January 2011

With an extensive data set on visits made to control the H7N7 avian influenza epidemic in the Netherlands in 2003 we investigate the potential role of the persons involved in the control activities as vectors for disease transmission. We hypothesized that people can spread the virus on the same day mechanically, or till 10 days if they have become infected themselves. Taken into account was the estimated time of introduction of the virus into a poultry flock back‐calculated from mortality data. We identified 19 visits from a person that went on the same day from an infected (source) farm to a (target) farm that was before infection and a further 197 visits were made to (target) farms that remained uninfected. Of the 19 visits, eight were made within 3 days before an infection started on the target farm. If we assume that these eight visits were the primary reason the visited farms became infected, then we can calculate an upper estimate for the probability of transmission by a person per visit of 0.037. In addition we identified visits were a person first visited an infected source farm and up to 10 days after visited a target farm that either remained uninfected or was before infection. Most visits to infected source farms were made just after infection. Animals on these farms were likely not yet symptomatic, thus escaping diagnosis. Such events may be difficult to prevent, although awareness of this possibility is already a major step towards prevention. Most of these visits involved tracing and screening and were made by a relatively small number of trained veterinarians. This makes it possible to focus training efforts specifically on these persons and make sure they stringently use the personal protective equipment and strictly follow the hygiene protocol, to protect them and prevent them from spreading the disease.
Avulsion and storage media
Authors: Hiremath Geeta , Kidiyoor Krishnamurthy H.
Published: January 2011

Avulsion of a tooth caused by trauma, and its successful treatment is a challenging situation that a dentist encounters in clinical practice. There is a definitive treatment for the avulsed tooth, which depends on many factors. The immediate replacement and replantation of the avulsed tooth is necessary, but it cannot always be accomplished for a number of reasons. Thus, the tooth should be transported in a suitable medium to maintain the cell viability. The storage medium is one of the important factors that will help the dentist in rendering successful treatment for the avulsed tooth. There is a continuing search for an ideal storage medium. This review paper focuses on the various storage media, with special reference to coconut water.
Facilitated transporters mediate net efflux of amino acids to the fetus across the basal membrane of the placental syncytiotrophoblast
Authors: Cleal J. K. , Glazier J. D. , Ntani G. , Crozier S. R. , Day P. E. , Harvey N. C. , Robinson S. M. , Cooper C. , Godfrey K. M. , Hanson M. A. , Lewis R. M.
Published: January 2011

Non‐technical summary Fetal growth depends on transfer of amino acids from the mother to the fetus via the placenta: the interface between the maternal and fetal circulations. We know how amino acids enter the placenta from the maternal blood, but it was not known how the amino acids exit the placenta to reach the fetus. Our work has now provided the first experimental evidence for a novel transport system which provides net amino acid transport to the fetus and influences fetal growth.
Role of an extracellular loop in determining the stoichiometry of Na+–HCO3− cotransporters
Authors: Chen Li‐Ming , Liu Ying , Boron Walter F.
Published: January 2011

Non‐technical summary The Na+–HCO3− cotransporters NBCe1 and NBCn1 play critical roles in the regulation of intracellular pH and in acid–base movement across epithelial barriers such as the kidney. NBCe1 appears to carry 1 Na+ for every 2 or 3 HCO3− and thus is electrogenic (carries electrical current) and NBCn1 appears to carry 1 Na+ for every 1 HCO3− and thus is electroneutral (carries no electrical current). We systematically substituted homologous pieces of NBCn1 into NBCe1 and made the surprising observation that a putative extracellular loop (previously thought to be an unstructured segment of protein that dangles in the extracellular fluid) plays a key role in determining the stoichiometry of NBCe1 and NBCn1. We found that replacing just the fourth extracellular loop of NBCe1 with that of NBCn1 fully eliminates the electrogenicity, and that the opposite substitution converts an electroneutral chimera into one capable of electrogenic transport.
Finite Element Modeling of Structures With L-Shaped Beams and Bolted Joints
Authors: He K. , Zhu W. D.
Published: January 2011

Due to bending-torsion coupled vibrations of the L-shaped beams and numerous uncertainties associated with the bolted joints, modeling structures with L-shaped beams and bolted joints is a challenging task. With the recent development of the modeling techniques for L-shaped beams by the authors (He and Zhu, 2009, “Modeling of Fillets in Thin-Walled Beams Using Shell/Plate and Beam Finite Elements,” ASME J. Vibr. Acoust., 131(5), p. 051002), this work focuses on developing new finite element (FE) models for bolted joints in these structures. While the complicated behavior of a single bolted connection can be analyzed using commercial FE software, it is computationally expensive and inefficient to directly simulate the global dynamic response of an assembled structure with bolted joints, and it is necessary to develop relatively simple and accurate models for bolted joints. Three new approaches, two model updating approaches and a predictive modeling approach, are developed in this work to capture the stiffness and mass effects of bolted joints on the global dynamic response of assembled structures. The unknown parameters of the models in the model updating approaches are determined by comparing the calculated and measured natural frequencies. In the predictive modeling approach, the effective area of a bolted connection is determined using contact FE models and an analytical beam model; its associated stiffnesses can also be determined. The models developed for the bolted joints have relatively small sizes and can be easily embedded into a FE model of an assembled structure. For the structures studied, including a three-bay space frame structure with L-shaped beams and bolted joints, and some of its components, the errors between the calculated and measured natural frequencies are within 2% for at least the first 13 elastic modes, and the associated modal assurance criterion values are all over 94%.
Vibration Analysis of Submerged Submarine Pressure Hull
Authors: Shariati Seyed Khalil , Mogadas Saeed Mahjob
Published: January 2011

Ring stiffened cylindrical shells are used in many structural applications, such as pressure vessels, submarine hulls, aircrafts, launch vehicles, and waterborne ballistic missiles. Most of these structures are required to operate while subjected to some form of dynamic loading and some of these can be quite severe. Submerged structures, such as submarines, torpedoes, and waterborne missiles, are all subjected to external pressure and are required to operate in a variety of environments where they can be subjected to different loads and conditions. Therefore, the analysis of the dynamic characteristics of these shells under external water pressure is crucial to ensure safe and successful designs. Therefore, in this research, we have considered their vibration analysis. To do this, we have considered the finite element method for vibration analysis of submerged structure and finally by using ANSYS software. We analyzed the free vibration of some models, which have been presented in some papers. After confirmation of the results, we have extended this method to analysis of imaginary submerged pressure hull of submarine.
Curing and Consolidation of Advanced Thermoset Composite Laminate Parts by Pressing Between a Heated Mold and Customized Rubber-Faced Mold
Authors: Walczyk Daniel , Kuppers Jaron , Hoffman Casey
Published: January 2011

Curing and consolidating thermoset composite laminates and sandwich structures typically involves vacuum bagging an uncured and formed layup over a thin-walled mold, placing it in an autoclave, and subjecting the entire unit to temperature, vacuum, and pressure cycles as prescribed by the manufacturer. Autoclaving is generally considered the major bottleneck in manufacturing advanced composite parts because of high capital and consumable costs, energy usage, waste generated, and process scalability. A new curing and consolidation process called “thermal press curing” is presented and demonstrated as an alternative to autoclaving. The process involves compressing a composite laminate between a special mold set––a heated metal mold and a matching rubber-covered mold made of an insulative material––designed to provide uniform temperature and pressure over the metal mold surface, that is, mimic the process conditions provided by an autoclave. The thermal press curing process is demonstrated for the first time using a mold set for a simple two-dimensional axisymmetric shape. An aluminum curing mold with embedded electric resistance cartridge heaters is heuristically designed to provide uniform temperature in operation across the mold surface within 1°C of the target value (177°C). With the mold set compressing an eight-ply carbon/epoxy composite workpiece and well insulated on all sides, the power draw is at least one to two orders of magnitude less than a comparable autoclaving operation. The potential to significantly improve pressure uniformity from the compressed rubber mask is shown by changing the mask shape. Even without an optimized rubber layer shape and thickness, the eight-ply composite part was successfully cured. Finally, a plan for future work is described.
Morphology and reconstructions of polar CdTe(111)A,B surfaces by scanning tunneling microscopy
Authors: Egan C. K. , Jiang Q. Z. , Brinkman A. W.
Published: January 2011

The morphology and reconstructions of clean CdTe(111)A and CdTe(111)B surfaces have been studied by scanning tunneling microscopy. The (111)A surface is highly ordered and has a (2×2) reconstruction with a cadmium vacancy structure. The CdTe(111)B surface shows a large amount of disorder with small ordered domains having a c(8×4) reconstruction. This consists of chains of atoms in a two layer structure sitting upon the bulk terminated surface. These chains extend in any of the ⟨211⟩ surface directions. A number of other surface structures were observed, but these showed little long-range ordering. For both surfaces, a certain amount of faceting on {311} planes was observed. This faceting suggests that the surface energy for the {111} surfaces is quite large.
Gate coupling and carrier distribution in silicon nanowire/nanoribbon transistors operated in electrolyte
Authors: Chen Si , Zhang Shi-Li
Published: January 2011

The transfer characteristics of back-gate silicon nanowire/nanoribbon (NW/NR) transistors measured in electrolyte exhibit a significantly higher on-current and a steeper subthreshold behavior than measured in air. Simulation results show that the gate capacitance for a NW/NR of a trapezoidal cross-section immersed in water is significantly higher than that exposed to air. Electrostatics simulations further show that for NWs/NRs with small widths, carriers are mainly accumulated at the two side-edges when they are immersed in water. Even the top surface of the NWs/NRs sees more accumulated carriers than the bottom one does; the latter is in fact located closest to the back-gate. These observations suggest that the interface properties at the side-edges and the top surface are crucial for NW/NR transistors to achieve high sensitivity when performing real-time sensing experiments in electrolyte. Finally, the sensitivity of back-gate NW/NR field-effect transistors to charge changes in electrolyte is found to have a weak dependence on the NW/NR width when the doping concentration is below 1017 cm−3. For higher NW/NR doping concentrations, narrower NWs/NRs are more sensitive.
Study of plasma dynamics in a modulated pulsed power magnetron discharge using a time-resolved Langmuir probe
Authors: Meng L. , Cloud A. N. , Jung S. , Ruzic D. N.
Published: January 2011

Modulated pulse power (MPP) technology is a derivative of high power pulsed magnetron sputtering that allows unprecedented user control over the growth process, although the critical time-dependent plasma properties during the power pulse have not been studied until now. Using a MPP plasma generator, pulses of custom voltage waveforms were generated and applied to the cathode of a 36 cm diameter circular planar magnetron. The I-V characteristics of the pulses are separable into distinct discharge stages. A time-resolved triple Langmuir probe was introduced to measure the temporal evolution of the plasma. Typical electron density of 5×1017 m−3 and electron temperature of 10 eV during the pulse were calculated from measured parameters. Plasma behaviors were observed to closely depend on the pulse waveforms. Various parameters, including pulse current, pulse frequency, pressure, and distance from the target, also affected the electron density and temperature, providing degrees of freedom to optimize the sputtering processes. The effects of each parameter on the pulsed plasma dynamics are discussed and then attributed to mechanisms of electron impact ionization, gas heating, and magnetic confinement.
Influence of pH and abrasive concentration on polishing rate of amorphous Ge2Sb2Te5 film in chemical mechanical polishing
Authors: Zhang Zefang , Liu Weili , Song Zhitang
Published: January 2011

This study explores the effect of pH and abrasive concentration on the chemical mechanical polishing (CMP) of blank amorphous Ge2Sb2Te5 (GST) film using the colloidal silica-based slurry. It was found that material removal rate (MRR) strongly depends on the pH and abrasive concentration. When using only pH adjusted de-ionized water, the MRR decreases as the pH was raised or lowered toward neutral, which indicates that chemical effects dominate in the polishing rates. However, electrostatic interactions between the abrasive particles and the surface of GST control the polishing rate with the variation in pH when the silica-based slurry was used. In addition, MRR was proportional to abrasive concentration and MRR per abrasive particle was calculated to explain the effect of abrasive concentration on GST CMP. With the variation of abrasive concentration, MRR is strongly correlated with coefficient of friction.
JAK and Jumonji: Deadly Playmates
Authors: Alumkal Joshi
Published: January 2011

An RNA interference genetic screen shows that JAK and JMJD2C cooperate to promote survival and progression of lymphomas.
Too Much of a Good Thing?
Authors: Cheng Elaine
Published: January 2011

Antibiotics alter the normal intestinal flora and increase susceptibility to infection by highly resistant bacteria.
Steroid and bile acids amide conjugates with D-glucosamine
Authors: Nováková Zdena , Tomanová Jana , Štěrbová Lucie , Drašar Pavel
Published: January 2011

New type of amide conjugates of steroid and bile acids with D-glucosamine 1 and 2 were prepared. Title compounds are prepared via acid chloride or using N-[({[(1E)-1-cyano-2-ethoxy-2-oxoethylidene]amino}oxy)(dimethylamino)methylidene]-N-methylmethanaminium tetrafluoroborate as condensation agent. They were examined for gelation properties with negative results. Per-O-acetylated D-glucosamine hydrochloride was prepared in one step procedure from D-glucosamine hydrochloride by acetylation in a mixture of acetyl chloride and acetic acid.
Supported task-specific ionic liquid catalyst for highly efficient and recyclable aerobic oxidation of benzyl alcohols
Authors: Liu Lin , Ma Juanjuan , Sun Zhen , Zhang Jianping , Huang Jingjing , Li Shanzhong , Tong Zhiwei
Published: January 2011

A novel catalytic system was prepared by impregnating ionic liquid immobilized 2,2,6,6-tetramethylpiperidyl-1-oxyl (TEMPO) and copper salt onto various silica supports. This catalytic system was capable of rapidly converting different benzylic and allylic alcohols into the corresponding aldehydes under O2 atmosphere with high conversion. Recycling results showed that the catalyst could be easily recovered and reused.
Modifications of commercial pressurized solvent extraction (PSE) systems for the analysis of polychlorinated biphenyls in avian whole blood and serum
Authors: Haskins Stacey D. , Harrison Christina M. , Kelly David G. , Weir Ron D.
Published: January 2011

The present study considers simple and cost-effective modifications to commercial pressurised solvent extraction cells to extract polychlorinated biphenyls (PCBs) from avian blood and serum. Blood and serum samples of mass 0.2 g were examined. Such masses are consistent with those which may be obtained from many avian species without sacrificing individuals or compromising breeding and (or) migratory success. Extraction vessels are modified by the use of Teflon inserts, which are readily fabricated at low cost. These inserts reduce internal cell volume and surface area. Thus, background contamination is reduced whilst extraction and rinse solvent is used more effectively to afford a small extract volume. Packing of the cell void with sodium sulfate and florisil achieves in situ sample dehydration and lipid removal. When combined with extraction concentration and large volume injection gas chromatography – ion-trap mass spectrometry (LVI-GC–ITMS), the extraction method is capable of polychlorinated biphenyl analysis without post-extraction clean-up. Validation was accomplished using commercial chicken whole blood and serum, and PCB congeners 28, 77, 105, 126, 153, 167, 170, 180, 183, and 194. Surrogate corrected recoveries in the range of 75% to120% for whole blood and 80% to115% for serum were obtained. Detection limits were in the range of 0.01 to 0.22 ng g–1 for whole blood and 0.03 to 0.45 ng g–1 for serum. The relative standard deviations for all congeners investigated were better than 15%.
Ganoderma lucidum Polysaccharides: Immunomodulation and Potential Anti-Tumor Activities
Authors: Xu Zengtao , Chen Xiuping , Zhong Zhangfeng , Chen Lidian , Wang Yitao
Published: January 2011

Ganoderma lucidum (G. lucidum), a basidiomycete white rot fungus, has long been prescribed to prevent and treat various human diseases, particularly in China, Japan, and Korea. Several classes of bioactive substances have been isolated and identified from G. lucidum, such as triterpenoids, polysaccharides, nucleosides, sterols, and alkaloids, among others. This paper examines the potential role of G. lucidum polysaccharide (GLPS) in tumor therapy and the possible mechanisms involved. Both in vitro and in vivo studies suggested that the anti-tumor activities of GLPS are mediated by its immunomodulatory, anti-angiogenic, and cytotoxic effects. GLPS affects immune cells and immune-related cells including B lymphocytes, T lymphocytes, dendritic cells, macrophages, and natural killer cells. In addition, recent data also suggest that GLPS suppresses tumorigenesis or inhibits tumor growth through direct cytotoxic effect and anti-angiogenic actions. However, many questions still need to be answered before both G. lucidum and GLPS can be widely accepted and used as anti-tumor agents.
Anti-Diabetic Effects of aCoptis chinensisContaining New Traditional Chinese Medicine Formula in Type 2 Diabetic Rats
Authors: Zhen Zhong , Chang Bai , Li Min , Lian Feng-Mei , Chen Liang , Dong Liu , Wang Jia , Yu Bo , Liu Wen-Ke , Li Xiu-Yang , Qin Pei-Jie , Zhang Jing-Hua , Tong Xiao-Lin
Published: January 2011

The Chinese formula Tang-Min-Ling (TML), an improved product of the decoction of Dachaihu which has a history of more than 2000 years, has main constituents of Coptis chinensis Franch, Scutellaria baicalensis Georgi, Rheum officinale Baill and Bupleurum chinense DC. A multi-central randomized controlled investigation performed previously by us has showed that TML has positive effects on regulating glycometabolism in type 2 diabetes (T2DM) patients, but the mechanisms remain unclear. Using Otsuka Long-Evans Tokushima Fatty (OLETF) rats as an animal model with rosiglitazone as a positive control, we were able to detect TML's effect on the serum glucose, serum lipid, serum leptin and adiponcetin after oral administration for 12 weeks. We were also able to detect the insulin resistance level by a glucose clamp test and study the mechanisms of TML in improving insulin resistance by detecting skeletal muscle AMP-activated protein kinase (AMPK) and glucose transporter 4 (GLUT4). Results showed that TML significantly reduced the glucose area under a curve of the oral glucose tolerance test, and had a positive effect in regulating serum lipid metabolism. TML treatment also significantly reduced the serum leptin level, but it had no effect on the serum adiponectin level. The AMPK enzymatic activity and GLUT4 expression in Skeletal Muscle were also upregulated in the TML group. The results suggest that the Chinese medicine TML, which contains Coptis chinensis Franch as one of its components, improves glycometabolism and its possible mechanisms may involve in improvement of insulin resistance of OLETF rats.
Antioxidant Activities of Dracocephalum tanguticum Maxim Extract and Its Up-Regulation on the Expression of Neurotrophic Factors in a Rat Model of Permanent Focal Cerebral Ischemia
Authors: Xu Jin-Xiu , Yang Mu , Deng Ke-Jun , Zhou Hong
Published: January 2011

The aim of this study was to investigate the effect of a BuOH-soluble fraction from Dracocephalum tanguticum Maxim (DME), which contained 52% of total flavonoid, on the cerebral ischemia injury induced by permanent middle cerebral artery occlusion (pMCAO) in rats. RT-PCR and Western blot analysis showed that DME (30 mg/kg/day for seven days) by intragastric administration modulated the mRNA expression and protein synthesis of two neurotrophic factors: brain-derived neurotrophic factor (BDNF) and neurotrophin 3 (NT-3). DME was effective in stimulating BDNF mRNA expression and protein synthesis in the ipsilateral frontal cortex (IFC) of both the sham-operated and pMCAO rats and this effect was also observed in the hippocampus of the pMCAO rats. DME significantly increased NT-3 mRNA expression and protein synthesis in the IFC and hippocampus of the pMCAO rats, although it had no effect on NT-3 expression in the sham-operated groups. Meanwhile, DME also decreased the malondialdehyde contents in the hippocampus of the sham-operated and pMCAO groups, and significantly attenuated the decrease of endogenous antioxidant (superoxide dismutase, glutathione peroxidase and catalase) activities in both the IFC and hippocampus of the rats after ischemia insult injury. Moreover, DME facilitated the neurobehavioral recovery after the cerebral ischemia. These findings suggested that DME has potential for treatment of ischemia-induced brain damage through stimulation of antioxidant activity and neurotrophic factor synthesis.
Therapeutic Effect of Korean Red Ginseng on Inflammatory Cytokines in Rats with Focal Cerebral Ischemia/Reperfusion Injury
Authors: Lee Jong Seok , Choi Han Sung , Kang Sung Wook , Chung Joo-Ho , Park Hun Kuk , Ban Ju Yeon , Kwon Oh Young , Hong Hoon Pyo , Ko Young Gwan
Published: January 2011

This study aims to identify the therapeutic effect of Korean red ginseng (KRG) on the expression of inflammatory cytokines in rats with focal cerebral ischemia/reperfusion injury. Adult male Sprague-Dawley rats were subjected to transient middle cerebral artery occlusion (tMCAO) for two hours. They were fed KRG extract (100 mg/kg/day per orally) or saline after reperfusion. Tests for neurological deficits, using the modified neurologic severity score and the corner turn test, were performed before the ischemic event, and one, three, and seven days after tMCAO. Serum levels of cytokines were measured three and seven days after the operation, using enzyme-linked immunosorbent assays. The infarct volume was assessed after seven days by staining brain tissue with 2% 2, 3, 5-triphenyltetrazolium chloride. Oral administration of KRG significantly reduced the infarct volumes and rapidly improved neurological deficits. Serum levels of tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β), and IL-6 were higher in tMCAO-operated rats than in the sham-operated rats. These changes were attenuated by daily KRG intake for seven days. Serum IL-10 levels were significantly increased in KRG-fed rats, as compared to sham-operated and saline-fed rats. Our results suggested that KRG provides neuroprotection for rats with focal cerebral ischemia/reperfusion injury. This neuroprotection may be due to raised IL-10 expression and a reduction in the serum levels of TNF-α, IL-1β, and IL-6.
Empetrum nigrumvar.japonicumExtract Suppresses γ-Ray Radiation-Induced Cell Damage via Inhibition of Oxidative Stress
Authors: Kim Ki Cheon , Lee In Kyung , Kang Kyoung Ah , Kim Bum Joon , Kim Daeshin , Moon Ji Young , Yoo Byoung Sam , Hyun Jin Won
Published: January 2011

The ethylacetate fraction of Empetrum nigrum var. japonicum (ENE) was shown to reduce intracellular reactive oxygen species (ROS) generated by γ-radiation and activate antioxidant enzymes, such as superoxide dismutase (SOD), catalase (CAT), and gluthathion peroxidase (GPx). ENE protected cells against radiation-induced cellular DNA damage, membrane lipid peroxidation, and protein modification, which are the main points of radiation-induced damage. In addition, ENE recovered cell viability by inhibiting apoptosis after cells were treated with radiation. ENE treatment also reduced γ-radiation induced Bax, and caspase 9 and 3 expression in irradiated cells. However, irradiated cells with ENE recovered Bcl-2 expression, which was reduced by radiation. This anti-apoptotic effect of ENE was due to the inhibition of mitogen-activated protein kinase kinase-4 (MKK4/SEK1)-c-Jun NH2-terminal kinase (JNK) cascades induced by γ-radiation. In summary, these results suggest that ENE protects cells against γ-radiation-induced oxidative stress via the reduction of ROS and attenuation of apoptosis.
Anti-Inflammatory Activity of Hyperoside Through the Suppression of Nuclear Factor-κB Activation in Mouse Peritoneal Macrophages
Authors: Kim Su-Jin , Um Jae-Young , Hong Seung-Heon , Lee Ju-Young
Published: January 2011

Hyperoside (quercetin-3-O-galactoside) is a flavonoid compound mainly found in the herb plants Hypericum perforatum L and Crataegus pinnatifida. Although hyperoside has a variety of pharmacological effects including anti-viral, anti-oxidative, and anti-apoptotic activities, the anti-inflammatory mechanism of hyperoside in mouse peritoneal macrophages remains unclear. In this study, hyperoside was shown to exert an anti-inflammatory action through suppressed production of tumor necrosis factor, interleukin-6, and nitric oxide in lipopolysaccharide-stimulated mouse peritoneal macrophages. The maximal inhibition rate of tumor necrosis factor-α, interleukin-6, and nitric oxide production by 5 μM hyperoside was 32.31 ± 2.8%, 41.31 ± 3.1%, and 30.31 ± 4.1%, respectively. In addition, hyperoside inhibited nuclear factor-κB activation and IκB-α degradation. The present study suggests that an important molecular mechanism by hyperoside reduces inflammation, which might explain its beneficial effect in the regulation of inflammatory reactions.
CORRELATION BASED FACE MATCHING IN COMBINED GLOBAL AND LOCAL PRESERVING FEATURE SPACE
Authors: SOUNDAR K. RUBA , MURUGESAN K.
Published: January 2011

Face recognition plays a vital role in authentication, monitoring, indexing, access control and other surveillance applications. Much research on face recognition with various feature based approaches using global or local features employing a number of similarity measurement techniques have been done earlier. Feature based approaches using global features can effectively preserve only the Euclidean structure of face space, that suffer from lack of local features which may play a major role in some applications. On the other hand, wtih local features only the face subspace that best detects the essential face manifold structure is obtained and it also suffers loss in global features which may also be important in some other applications. Measuring similarity or distance between two feature vectors is also a key step for any pattern matching application. In this work, a new combined approach for recognizing faces that integrates the advantages of the global feature extraction technique by Linear Discriminant Analysis (LDA) and the local feature extraction technique by Locality Preserving Projections (LPP) with correlation based similarity measurement technique has been discussed. This has been validated by performing various experiments and by making a fair comparison with conventional methods.
ROTATION INVARIANT MULTIVIEW FACE DETECTION USING SKIN COLOR REGRESSIVE MODEL AND SUPPORT VECTOR REGRESSION
Authors: PAUL PADMA POLASH , MONWAR MD. MARUF , GAVRILOVA MARINA L. , WANG PATRICK S. P.
Published: January 2011

In this paper, an automatic rotation invariant multiview face detection method, which utilizes modified Skin Color Model (SCM), is presented. First, Gaussian Mixture Model (GMM) and Support Vector Machine (SVM) based hybrid models are used to classify human skin regions from color images. The novelty of the adaptive hybrid model is its ability to predict the chromatic skin color band for individual images based on calibration differences of camera and luminance condition of environment. Classified skin regions are then converted to gray scale image with a threshold based on the predicted chromatic skin color bands, which further enhances detection performance. Next, Principle Component Analysis (PCA) is applied to gray segmented regions. Face detection is carried out based on the PCA-based extracted features, along with selected features, using support vector regression. The output of this procedure is used to report the final result of face detection. The proposed method is also beneficial for the rotation invariant face recognition problem.
IMPROVEMENT OF IRIS RECOGNITION PERFORMANCE USING REGION-BASED ACTIVE CONTOURS, GENETIC ALGORITHMS AND SVMs
Authors: ROY KAUSHIK , BHATTACHARYA PRABIR
Published: January 2011

Most existing iris recognition algorithms focus on the processing and recognition of the ideal iris images that are acquired in a controlled environment. In this paper, we process the nonideal iris images that are captured in an unconstrained situation and are affected severely by gaze deviation, eyelids and eyelashes occlusions, nonuniform intensity, motion blur, reflections, etc. The proposed iris recognition algorithm has three novelties as compared to the previous works; firstly, we deploy a region-based active contour model to segment a nonideal iris image with intensity inhomogeneity; secondly, genetic algorithms (GAs) are deployed to select the subset of informative texture features without compromising the recognition accuracy; Thirdly, to speed up the matching process and to control the misclassification error, we apply a combined approach called the adaptive asymmetrical support vector machines (AASVMs). The verification and identification performance of the proposed scheme is validated on three challenging iris image datasets, namely, the ICE 2005, the WVU Nonideal, and the UBIRIS Version 1.
SYNTHESIS AND CHARACTERIZATION OF FLUORESCENT Cu2S NANOPARTICLES EMBEDDED IN AMORPHOUS POLYSTYRENE
Authors: CAROTENUTO G. , CAPEZZUTO F. , PALOMBA M. , NICOLAIS F.
Published: January 2011

Very small Cu2S nanoparticles have been generated inside an amorphous polystyrene matrix by thermal decomposition of Cu(I) mercaptide molecules dissolved in the polymer. The resulting nanocomposite material was transparent, yellow colored, and characterized by a quite strong red luminescence. In particular, the sample photoluminescence (PL) spectrum showed three excitation wavelengths and a quite broad emission band resulting from the combination of band-edge and trap-state emission. However, luminescence was not stable over the time and a quenching phenomenon was observed after a time period of ca. three months.
LASER-INDUCED PHOTOLUMINESCENT STUDIES OF Al-DOPED ZINC OXIDE NANOPARTICLES
Authors: KUMAR DHIRAJ , KUMAR SUNIL , BHATTI H. S.
Published: January 2011

In this paper, addition of aluminum in zinc oxide is incorporated using low-temperature chemical synthesis route. Aluminum ions help in crystallization of zinc oxide nanoparticles. Characterization of the synthesized nanoparticles of zinc oxide has been done using Transmission electron microscope (TEM), and X-ray diffraction (XRD) analysis, Energy-resolved photoluminescence (PL) spectra and Time-resolved laser-induced photoluminescence (TRPL) at room temperature. Transmission electron microscopic observations and X-Ray diffraction studies indicate highly crystalline nature and particle size of the order of 20 nm in ZnO:Al . Time-resolved laser-induced photoluminescence measurements have been done using pulsed nitrogen laser as an excitation source, operated at wavelength 337.1 nm and having high peak output power of 1 MW. The results show that at higher concentrations of Al doping in host ZnO phosphor, emission intensity is more by several orders of magnitude and lifetime shortening indicates that these nanoparticles are more efficient as compared with lower concentrations of dopant.
SPONTANEOUS SPIN POLARIZATION OF ELECTRONS IN SiGe/Si HETEROSTRUCTURES
Authors: PETER A. JOHN
Published: January 2011

The spin-dependent electron transmission phenomenon in an SiGe/Si/SiGe resonant semiconductor heterostructure is employed theoretically to investigate the output transmission current polarization at zero magnetic field. Transparency of electron transmission is calculated as a function of electron energy as well as the well width, within the one electron band approximation along with the spin-orbit interaction. Enhanced spin-polarized resonant tunneling in the heterostructure due to Dresselhaus and Rashba spin-orbit coupling induced splitting of the resonant level is observed. We predict that a spin-polarized current spontaneously emerges in this heterostructure and we estimate theoretically that the polarization can reach 100%. This effect could be employed in the fabrication of spin filters, spin injectors, and detectors based on nonmagnetic semiconductors.
BIOSYNTHESIS AND CHARACTERIZATION OF GOLD NANOPARTICLES USING THE ALGA Kappaphycus alvarezii
Authors: RAJASULOCHANA P. , DHAMOTHARAN R. , MURUGAKOOTHAN P. , MURUGESAN S. , KRISHNAMOORTHY P.
Published: January 2011

As a part of our ongoing investigation into the use of algae for gold nanoparticle synthesis, we screened the marine alga Kappaphycus alvarezii, to investigate its efficiency to reduce gold ions as well as the formation of gold nanoparticles. In the present work, we report the reaction condition of the alga K. alvarezii with aqueous gold ions for gold nanoparticle synthesis within the biomass extracellularly. The formation of gold nanoparticles was characterized by UV–Vis spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray diffraction (XRD) method. Moreover, we have found that the reaction of gold ions with the K. alvarezii biomass under stationary conditions results in the rapid extracellular formation of gold nanoparticles of spherical morphology. The gold nanoparticles are not toxic to the cells that continued to grow after the biosynthesis of the gold nanoparticles.
STRUCTURAL, OPTICAL AND MAGNETIC INVESTIGATIONS ON UNDOPED AND Mn-DOPED ZnO NANOPARTICLES
Authors: RAJKUMAR N. , RAMACHANDRAN K.
Published: January 2011

Undoped and Mn (1 and 3 at.%) doped ZnO nanoparticles were synthesized by a simple chemical co-precipitation method. Rietveld refinement of X-ray diffraction (XRD) data revealed that undoped and Mn doped ZnO nanoparticles crystallize in the monophasic wurtzite structure and monotonous expansion of the lattice constants with increasing Mn content, due to the effective Mn doping. TEM images of all the samples showed the monodispersive spherical particles with the size of ~7 nm. The quantum confinement of nanoparticles was tested from UV–Vis absorbance measurement and the particle sizes were calculated and compared with TEM and XRD. The chemical compositions were analyzed by energy dispersive spectroscopy (EDS). In order to investigate the origin of ferromagnetism, the electronic structures of the Zn , O , and Mn atoms were probed by X-ray photoelectron spectroscopy (XPS). XPS data revealed that most of the dopants (Mn) exists in +2 oxidation state for 3 at.% Mn doped ZnO sample. The magnetization curves of the Mn doped ZnO samples indicate the existence of room-temperature ferromagnetic (RTFM) behavior. Here the observed RTFM in Mn doped ZnO can be attributed to the substitutional incorporation of Mn at Zn sites rather than due to the formation of any secondary phases.
THE ASSEMBLY OF CHAIN-LIKE Ni ARRAYS UNDER MAGNETIC FIELD AND ITS ENHANCED PROPERTIES
Authors: WANG JUN , CAO SHIHE , XIA SIHUA , GAN NING
Published: January 2011

Chain-like nickel arrays assembled from magnetic Ni spheres were successfully prepared through a facile hydrothermal process at 200°C under a 0.25 T external magnetic field. The external magnetic field is strongly believed to be the driving force of the self-assembly. The sample was highly crystalline as confirmed by the X-ray diffraction (XRD) patterns. The scanning electron microscope (SEM) and transmission electron microscope (TEM) images show that all Ni spheres are closely interconnected to form chains, with ~ 950 nm in diameter and ~ 1 cm in length, which arrange into vertical arrays on the silicon substrate. The coercivity and remnant magnetization ratio of the sample, 670 Oe and 0.612, respectively, are substantially higher than for the sample prepared without an applied external magnetic field (68 Oe and 0.336). Such enhancements can be attributed to their novel superstructure, shape anisotropy, reduced demagnetization factor, etc. This process can be used to fabricate large arrays of uniform chains of magnetic materials and modulate their magnetic properties.
CYCLODEXTRIN-STABILIZED METAL NANOPARTICLES: SYNTHESIS AND CHARACTERIZATION
Authors: GOPALAN PUSHPA R.
Published: January 2011

A simple and novel method of synthesis of gold and silver nanoparticles from their salt solutions by amino acid reduction in the presence of β-Cyclodextrin as capping and stabilizing agent has been successfully carried out. Characterization is done by UV spectroscopy and High-Resolution Transmission Electron Micrograph (HRTEM) imaging. The size of the nanomaterials is found to lie in the range 5–100 nm. The aqueous solutions of metal nanomaterials are stable for months, indicating the encapsulation of them in the nanocavity of β-Cyclodextrin. This report is new and novel as it is a combination of nanoscience with Supramolecular Chemistry. Cyclodextrin-capped metal nanoparticles will exhibit selectivity in properties derived from host–guest phenomena on their surfaces and are novel nanocatalysts for catalytic organic reactions in aqueous solution. Cyclodextrins are found to be very effective and eco-friendly alternatives to surfactants and polymer matrices as stabilizers.
Synchronous dataflow scenarios
Authors: Geilen Marc
Published: January 2011

The Synchronous Dataflow (SDF) model of computation by Lee and Messerschmitt has become popular for modeling concurrent applications on a multiprocessor platform. It is used to obtain a guaranteed, predictable performance. The model, on the other hand, is quite restrictive in its expressivity, making it less applicable to many modern, more dynamic applications. A common technique to deal with dynamic behavior is to consider different scenarios in separation. This analysis is, however, currently limited mainly to sequential applications.

In this article, we present a new analysis approach that allows analysis of synchronous dataflow models across different scenarios of operation. The dataflow graphs corresponding to the different scenarios can be completely different. Execution times, consumption and production rates and the structure of the SDF may change. Our technique allows to derive or prove worst-case performance guarantees of the resulting model and as such extends the model-driven approach to designing predictable systems to significantly more dynamic applications and platforms. The approach is illustrated with three MP3 and MPEG-4 related case studies.