bluuebunny/crossref_metadata_2025 huggingface dataset:
Signal-to-noise ratio in the membrane potential of the owl's auditory coincidence detectors
Authors: Ashida Go , Funabiki Kazuo , Kuokkanen Paula T. , Kempter Richard , Carr Catherine E.
Published: August 2012

Owls use interaural time differences (ITDs) to locate a sound source. They compute ITD in a specialized neural circuit that consists of axonal delay lines from the cochlear nucleus magnocellularis (NM) and coincidence detectors in the nucleus laminaris (NL). Recent physiological recordings have shown that tonal stimuli induce oscillatory membrane potentials in NL neurons (Funabiki K, Ashida G, Konishi M. J Neurosci 31: 15245–15256, 2011). The amplitude of these oscillations varies with ITD and is strongly correlated to the firing rate. The oscillation, termed the sound analog potential, has the same frequency as the stimulus tone and is presumed to originate from phase-locked synaptic inputs from NM fibers. To investigate how these oscillatory membrane potentials are generated, we applied recently developed signal-to-noise ratio (SNR) analysis techniques (Kuokkanen PT, Wagner H, Ashida G, Carr CE, Kempter R. J Neurophysiol 104: 2274–2290, 2010) to the intracellular waveforms obtained in vivo. Our theoretical prediction of the band-limited SNRs agreed with experimental data for mid- to high-frequency (>2 kHz) NL neurons. For low-frequency (≤2 kHz) NL neurons, however, measured SNRs were lower than theoretical predictions. These results suggest that the number of independent NM fibers converging onto each NL neuron and/or the population-averaged degree of phase-locking of the NM fibers could be significantly smaller in the low-frequency NL region than estimated for higher best-frequency NL.
Signal coding in cockroach photoreceptors is tuned to dim environments
Authors: Heimonen K. , Immonen E.-V. , Frolov R. V. , Salmela I. , Juusola M. , Vähäsöyrinki M. , Weckström M.
Published: August 2012

In dim light, scarcity of photons typically leads to poor vision. Nonetheless, many animals show visually guided behavior with dim environments. We investigated the signaling properties of photoreceptors of the dark active cockroach ( Periplaneta americana) using intracellular and whole-cell patch-clamp recordings to determine whether they show selective functional adaptations to dark. Expectedly, dark-adapted photoreceptors generated large and slow responses to single photons. However, when light adapted, responses of both phototransduction and the nontransductive membrane to white noise (WN)-modulated stimuli remained slow with corner frequencies ∼20 Hz. This promotes temporal integration of light inputs and maintains high sensitivity of vision. Adaptive changes in dynamics were limited to dim conditions. Characteristically, both step and frequency responses stayed effectively unchanged for intensities >1,000 photons/s/photoreceptor. A signal-to-noise ratio (SNR) of the light responses was transiently higher at frequencies <5 Hz for ∼5 s after light onset but deteriorated to a lower value upon longer stimulation. Naturalistic light stimuli, as opposed to WN, evoked markedly larger responses with higher SNRs at low frequencies. This allowed realistic estimates of information transfer rates, which saturated at ∼100 bits/s at low-light intensities. We found, therefore, selective adaptations beneficial for vision in dim environments in cockroach photoreceptors: large amplitude of single-photon responses, constant high level of temporal integration of light inputs, saturation of response properties at low intensities, and only transiently efficient encoding of light contrasts. The results also suggest that the sources of the large functional variability among different photoreceptors reside mostly in phototransduction processes and not in the properties of the nontransductive membrane.
Lessons Learned from Implementing the Patient-Centered Medical Home
Authors: Green Ellen P. , Wendland John , Carver M. Colette , Hughes Rinker Cortney , Mun Seong K.
Published: August 2012

The Patient-Centered Medical Home (PCMH) is a primary care model that provides coordinated and comprehensive care to patients to improve health outcomes. This paper addresses practical issues that arise when transitioning a traditional primary care practice into a PCMH recognized by the National Committee for Quality Assurance (NCQA). Individual organizations' experiences with this transition were gathered at a PCMH workshop in Alexandria, Virginia in June 2010. An analysis of their experiences has been used along with a literature review to reveal common challenges that must be addressed in ways that are responsive to the practice and patients’ needs. These are: NCQA guidance, promoting provider buy-in, leveraging electronic medical records, changing office culture, and realigning workspace in the practice to accommodate services needed to carry out the intent of PCMH. The NCQA provides a set of standards for implementing the PCMH model, but these standards lack many specifics that will be relied on in location situations. While many researchers and providers have made critiques, we see this vagueness as allowing for greater flexibility in how a practice implements PCMH.
Multiobjective Optimization of Aircraft Maintenance in Thailand Using Goal Programming: A Decision-Support Model
Authors: Pleumpirom Yuttapong , Amornsawadwatana Sataporn
Published: August 2012

The purpose of this paper is to develop the multiobjective optimization model in order to evaluate suppliers for aircraft maintenance tasks, using goal programming. The authors have developed a two-step process. The model will firstly be used as a decision-support tool for managing demand, by using aircraft and flight schedules to evaluate and generate aircraft-maintenance requirements, including spare-part lists. Secondly, they develop a multiobjective optimization model by minimizing cost, minimizing lead time, and maximizing the quality under various constraints in the model. Finally, the model is implemented in the actual airline's case.
Global Attractor of Atmospheric Circulation Equations with Humidity Effect
Authors: Luo Hong
Published: August 2012

Global attractor of atmospheric circulation equations is considered in
this paper. Firstly, it is proved that this system possesses a unique global weak
solution in L2(Ω, R4). Secondly, by using C‐condition, it is obtained that atmospheric
circulation equations have a global attractor in L2(Ω, R4).
Threshold Effects for the Generalized Friedrichs Model with the Perturbation of Rank One
Authors: Lakaev Saidakhmat , Ibrahim Arsmah , Kurbanov Shaxzod
Published: August 2012

A family Hμ(p), μ > 0, p ∈ 𝕋2 of the Friedrichs models with the perturbation of rank
one, associated to a system of two particles, moving on the two‐dimensional lattice ℤ2 is considered.
The existence or absence of the unique eigenvalue of the operator Hμ(p) lying below threshold
depending on the values of μ > 0 and p ∈ Uδ(0) ⊂ 𝕋2 is proved. The analyticity of corresponding
eigenfunction is shown.
Location Privacy and Energy Preservation in Sensor Allocation Systems
Authors: Rowaihy Hosam
Published: August 2012

We propose sensor-to-task assignments algorithms that take into account location privacy issues. Our solutions enable the network to choose the “best” assignment of the available sensors to the tasks to maximize the utility of the network while preserving sensors’ location privacy. We focus on preserving the sensors’ locations during the assignment process in contrast to previous works, which considered location privacy while sensors are in operation. We also propose an energy-based algorithm that uses the remaining energy of a sensor as a factor to scale the distance between a sensor and a task such that sensors that have more energy appear to be closer than ones with less energy left. This does not only provide location privacy but will also consume the sensing resources more evenly, which leads to extending the lifetime of the network. From our simulations, we found that our algorithms can successfully hide sensors’ locations while providing performance close to the algorithms, which use the exact locations. In addition, our energy-based algorithm, while achieving results close to the exact location algorithm, was found to increase the network lifetime by as much as 40%.
Intracellular Delivery of siRNA by Polycationic Superparamagnetic Nanoparticles
Authors: Castillo Betzaida , Bromberg Lev , López Xaira , Badillo Valerie , González Feliciano Jose A. , González Carlos I. , Hatton T. Alan , Barletta Gabriel
Published: August 2012

The siRNA transfection efficiency of nanoparticles (NPs), composed of a superparamagnetic iron oxide core modified with polycationic polymers (poly(hexamethylene biguanide) or branched polyethyleneimine), were studied in CHO-K1 and HeLa cell lines. Both NPs demonstrated to be good siRNA transfection vehicles, but unmodified branched polyethyleneimine (25 kD) was superior on both cell lines. However, application of an external magnetic field during transfection (magnetofection) increased the efficiency of the superparamagnetic NPs. Furthermore, our results reveal that these NPs are less toxic towards CHO-K1 cell lines than the unmodified polycationic-branched polyethyleneimine (PEI). In general, the external magnetic field did not alter the cell’s viability nor it disrupted the cell membranes, except for the poly(hexamethylene biguanide)-modified NP, where it was observed that in CHO-K1 cells application of the external magnetic field promoted membrane damage. This paper presents new polycationic superparamagnetic NPs as promising transfection vehicles for siRNA and demonstrates the advantages of magnetofection.
A Family of Iterative Methods with Accelerated Eighth‐Order Convergence
Authors: Cordero Alicia , Fardi Mojtaba , Ghasemi Mehdi , Torregrosa Juan R.
Published: August 2012

We propose a family of eighth‐order iterative methods without memory for solving nonlinear equations. The new iterative methods are developed by using weight function method and using an approximation for the last derivative, which reduces the required number of functional evaluations per step. Their efficiency indices are all found to be 1.682. Several examples allow us to compare our algorithms with known ones and confirm the theoretical results.
Predicting Heats of Explosion of Nitroaromatic Compounds through NBO Charges and 15N NMR Chemical Shifts of Nitro Groups
Authors: Infante-Castillo Ricardo , Hernández-Rivera Samuel P.
Published: August 2012

This work presents a new quantitative model to predict the heat of explosion of nitroaromatic compounds using the natural bond orbital (NBO) charge and 15N NMR chemical shifts of the nitro groups (15NNitro) as structural parameters. The values of the heat of explosion predicted for 21 nitroaromatic compounds using the model described here were compared with experimental data. The prediction ability of the model was assessed by the leave-one-out cross-validation method. The cross-validation results show that the model is significant and stable and that the predicted accuracy is within 0.146 MJ kg−1, with an overall root mean squared error of prediction (RMSEP) below 0.183 MJ kg−1. Strong correlations were observed between the heat of explosion and the charges (R2 = 0.9533) and 15N NMR chemical shifts (R2 = 0.9531) of the studied compounds. In addition, the dependence of the heat of explosion on the presence of activating or deactivating groups of nitroaromatic explosives was analyzed. All calculations, including optimizations, NBO charges, and 15NNitro NMR chemical shifts analyses, were performed using density functional theory (DFT) and a 6-311+G(2d,p) basis set. Based on these results, this practical quantitative model can be used as a tool in the design and development of highly energetic materials (HEM) based on nitroaromatic compounds.
A Rare Case of Hemoptysis: Intrapulmonary Cavitary Lesion Appearing as a Thoracic Endometriosis
Authors: Celik Ali , Aydın Ertan , Yazıcı Ulku , Agackıran Yetkin , Karaoglanoglu Nurettin
Published: August 2012

Pulmonary endometriosis is a rarely seen disease of the lung. On computed tomography, a cavitary lesion of 15 × 26 in size was detected in the lung parenchyma of a 38-year-old female patient who was examined due to hemoptysis. The pathologic result of the surgically excised cavitary lesion was reported as pulmonary endometriosis.
Measurement of Salivary Resistin Level in Patients with Type 2 Diabetes
Authors: Yin Jinhua , Gao Hongfei , Yang Jing , Xu Lu , Li Ming
Published: August 2012

Serum resistin was initially hypothesized as a link between obesity and insulin resistance in mice. The latest evidence suggests that serum resistin is proinflammatory cytokines. Inflammation plays a key role in the pathogenesis of type 2 diabetes mellitus (T2DM). Many reports have previously identified changed serum resistin levels in patients with T2DM, but little is known of the levels of resistin in saliva. In our study, saliva and serum samples were collected from 38 patients with newly diagnosed T2DM at each time point of OGTT and 35 nondiabetic controls at fasting state. Resistin concentrations were measured using ELISA. We have demonstrated the presence of resistin in saliva of T2DM and nondiabetic subjects. Saliva resistin levels of T2DM are significantly higher than those of nondiabetic controls. Resistin levels in saliva are not affected by eating activity and correlated with serum resistin levels at any time points of OGTT. A positive correlation of serum and salivary resistin with BMI and HOMA-IR existed in T2DM. Measurement of resistin in saliva is a simple, noninvasive and may be an acceptable alternative to blood sampling for evaluatinginflammation/obesity/insulin resistance state.
Psychological Stress and the Cutaneous Immune Response: Roles of the HPA Axis and the Sympathetic Nervous System in Atopic Dermatitis and Psoriasis
Authors: Hall Jessica M. F. , Cruser desAnges , Podawiltz Alan , Mummert Diana I. , Jones Harlan , Mummert Mark E.
Published: August 2012

Psychological stress, an evolutionary adaptation to the fight-or-flight response, triggers a number of physiological responses that can be deleterious under some circumstances. Stress signals activate the hypothalamus-pituitary-adrenal (HPA) axis and the sympathetic nervous system. Elements derived from those systems (e.g., cortisol, catecholamines and neuropeptides) can impact the immune system and possible disease states. Skin provides a first line of defense against many environmental insults. A number of investigations have indicated that the skin is especially sensitive to psychological stress, and experimental evidence shows that the cutaneous innate and adaptive immune systems are affected by stressors. For example, psychological stress has been shown to reduce recovery time of the stratum corneum barrier after its removal (innate immunity) and alters antigen presentation by epidermal Langerhans cells (adaptive immunity). Moreover, psychological stress may trigger or exacerbate immune mediated dermatological disorders. Understanding how the activity of the psyche-nervous -immune system axis impinges on skin diseases may facilitate coordinated treatment strategies between dermatologists and psychiatrists. Herein, we will review the roles of the HPA axis and the sympathetic nervous system on the cutaneous immune response. We will selectively highlight how the interplay between psychological stress and the immune system affects atopic dermatitis and psoriasis.
Interference of Light in a Michelson-Morley Interferometer: A Quantum Optical Approach
Authors: Langangen Ø. , Vaskinn A. , Skagerstam B.-S.
Published: August 2012

The temporal coherence interference properties of light as revealed by single detector intensity measurements in a Michelson-Morley interferometer (MMI) is often described in terms of classical optics. We show, in a pedagogical manner, how such features of light also can be understood in terms of a more general quantum-optics framework. If a thermal reference source is used in the MMI local oscillator port in combination with a thermal source in the signal port, the interference pattern revealed by single detector intensity measurements shows a distinctive dependence on the differences in the temperature of the two sources. A related method has actually been used to perform high-precision measurements of the cosmic microwave background radiation. The general quantum-optics framework allows us to consider any initialquantum state. As an example, we consider the interference of single photons as a tool to determine the peak angular-frequency of a single-photon pulse interfering with a single-photon reference pulse. A similar consideration for laser pulses, in terms of coherent states, leads to a different response in the detector. The MMI experimental setup is therefore an example of an optical device where one, in terms of intensity measurements, can exhibit the difference between classical and quantum-mechanical light.
Homotopy Perturbation Method for Thin Film Flow and Heat Transfer over an Unsteady Stretching Sheet with Internal Heating and Variable Heat Flux
Authors: Liu I-Chung , Megahed Ahmed M.
Published: August 2012

We have analyzed the effects of variable heat flux and internal heat generation on the flow and heat transfer in a thin film on a horizontal sheet in the presence of thermal radiation. Similarity transformations are used to transform the governing equations to a set of coupled nonlinear ordinary differential equations. The obtained differential equations are solved approximately by the homotopy perturbation method (HPM). The effects of various parameters governing the flow and heat transfer in this study are discussed and presented graphically. Comparison of numerical results is made with the earlier published results under limiting cases.
A Privacy-Preserved Analytical Method for eHealth Database with Minimized Information Loss
Authors: Chen Ya-Ling , Cheng Bo-Chao , Chen Hsueh-Lin , Lin Chia-I , Liao Guo-Tan , Hou Bo-Yu , Hsu Shih-Chun
Published: August 2012

Digitizing medical information is an emerging trend that employs information and communication technology (ICT) to manage health records, diagnostic reports, and other medical data more effectively, in order to improve the overall quality of medical services. However, medical information is highly confidential and involves private information, even legitimate access to data raises privacy concerns. Medical records provide health information on an as-needed basis for diagnosis and treatment, and the information is also important for medical research and other health management applications. Traditional privacy risk management systems have focused on reducing reidentification risk, and they do not consider information loss. In addition, such systems cannot identify and isolate data that carries high risk of privacy violations. This paper proposes the Hiatus Tailor (HT) system, which ensures low re-identification risk for medical records, while providing more authenticated information to database users and identifying high-risk data in the database for better system management. The experimental results demonstrate that the HT system achieves much lower information loss than traditional risk management methods, with the same risk of re-identification.
A Modified Regularization Method for the Proximal Point Algorithm
Authors: Wang Shuang
Published: August 2012

Under some weaker conditions, we prove the strong convergence of the sequence generated by a modified regularization method of finding a zero for a maximal monotone operator in a Hilbert space. In addition, an example is also given in order to illustrate the effectiveness of our generalizations. The results presented in this paper can be viewed as the improvement, supplement, and extension of the corresponding results.
Approximating Common Fixed Points of Nonspreading‐Type Mappings and Nonexpansive Mappings in a Hilbert Space
Authors: Kim Kyung Soo
Published: August 2012

We obtain some fundamental properties for k‐strictly pseudo‐nonspreading mappings in a Hilbert space. We study approximation of common fixed points of k‐strictly pseudo‐nonspreading mappings and nonexpansive mappings in a Hilbert space by using a new iterative scheme. Furthermore, we suggest some open problems.
On Some Extensions of Szasz Operators Including Boas‐Buck‐Type Polynomials
Authors: Sucu Sezgin , İçöz Gürhan , Varma Serhan
Published: August 2012

This paper is concerned with a new sequence of linear positive operators which generalize Szasz operators including Boas‐Buck‐type polynomials. We establish a convergence theorem for these operators and give the quantitative estimation of the approximation process by using a classical approach and the second modulus of continuity. Some explicit examples of our operators involving Laguerre polynomials, Charlier polynomials, and Gould‐Hopper polynomials are given. Moreover, a Voronovskaya‐type result is obtained for the operators containing Gould‐Hopper polynomials.
Lysosomal Fusion Dysfunction as a Unifying Hypothesis for Alzheimer's Disease Pathology
Authors: Funk Kristen E. , Kuret Jeff
Published: August 2012

Alzheimer's disease is characterized pathologically by extracellular senile plaques, intracellular neurofibrillary tangles, and granulovacuolar degeneration. It has been debated whether these hallmark lesions are markers or mediators of disease progression, and numerous paradigms have been proposed to explain the appearance of each lesion individually. However, the unfaltering predictability of these lesions suggests a single pathological nidus central to disease onset and progression. One of the earliest pathologies observed in Alzheimer's disease is endocytic dysfunction. Here we review the recent literature of endocytic dysfunction with particular focus on disrupted lysosomal fusion and propose it as a unifying hypothesis for the three most-studied lesions of Alzheimer's disease.
Coronary Subclavian Steal Syndrome Causing Acute Myocardial Infarction in a Patient Undergoing Coronary-Artery Bypass Grafting
Authors: Mandak Jiri , Lojik Miroslav , Tuna Martin , Chek James Lago
Published: August 2012

Coronary subclavian steal syndrome with retrograde blood flow in the left internal mammary-coronary bypass graft is a rare but severe complication of cardiac surgery. The authors present a case of a 68-year-old man after coronary-artery bypass grafting using an internal mammary artery. He had been suffering from angina pectoris for the last several years before surgery. The patient was resuscitated at home by emergency medical service because of primary ventricular fibrillation due to an acute myocardial infarction 5 years after surgery. An occlusion of the left subclavian artery with the retrograde blood flow in the left internal mammary coronary bypass was found. This could have been the cause of insufficiency in coronary blood flow and ischemia of the myocardial muscle. The subclavian artery occlusion was successfully treated with percutaneous transluminal angioplasty and implantation of 2 stents. The patient remained free of any symptoms 2 years after this procedure.
Nonlinear Analysis for Shear Augmented Dispersion of Solutes in Blood Flow through Narrow Arteries
Authors: Sankar D. S. , Jaafar Nurul Aini Binti , Yatim Yazariah
Published: August 2012

The shear augmented dispersion of solutes in blood flow (i) through circular tube and (ii) between parallel flat plates is analyzed mathematically, treating blood as Herschel‐Bulkley fluid model. The resulting system of nonlinear differential equations are solved with the appropriate boundary conditions, and the expressions for normalized velocity, concentration of the fluid in the core region and outer region, flow rate, and effective axial diffusivity are obtained. It is found that the normalized velocity of blood, relative diffusivity, and axial diffusivity of solutes are higher when blood is modeled by Herschel‐Bulkley fluid rather than by Casson fluid model. It is also noted that the normalized velocity, relative diffusivity, and axial diffusivity of solutes are higher when blood flows through circular tube than when it flows between parallel flat plates.
Imaging Review of Procedural and Periprocedural Complications of Central Venous Lines, Percutaneous Intrathoracic Drains, and Nasogastric Tubes
Authors: Al-Jahdali Hamdan , Irion Klaus L. , Allen Carolyn , de Godoy Daniel Marafiga , Khan Ali Nawaz
Published: August 2012

Placements of central venous lines (CVC), percutaneous intrathoracic drains (ITDs), and nasogastric tubes (NGTs) are some of the most common interventional procedures performed on patients that are unconscious and in almost all intensive care/high dependency patients in one form or the other. These are standard procedures within the remit of physicians, and other trained health professionals. Procedural complications may occur in 7%–15% of patients depending upon the intervention and experience of the operator. Most complications are minor, but other serious complications may add significantly to morbidity and even mortality of already compromised patients. Imaging findings are the key to the detection of misplaced lines, and tubes and their prompt recognition are vital to avoid harm to the patient. It is, therefore, pertinent that healthcare professionals who perform these procedures are familiar with imaging complications of these procedures. Here, we present the imaging characteristics of procedural complications.
A Poor Prognostic Case of Mucoepidermoid Carcinoma of the Thyroid: A Case Report
Authors: Shindo Koji , Aishima Shinichi , Okido Masayuki , Ohshima Akira
Published: August 2012

Mucoepidermoid carcinoma (MEC) of the thyroid is very rare and low-grade indolent neoplasm. In past reports of the thyroid MEC, only seven cases were described as poor prognosis. A 91-year-old woman presented with a rapidly growing mass of the left upper neck. She was followed thyroid papillary carcinoma (PC) without operation for two years. Fine needle aspiration cytology (FNAC) showed undifferentiated cells. Total thyroidectomy and bilateral neck dissection were performed. In pathological findings, the tumor had two areas of MEC and PC. The boundary of them was mixed. She died of multiple lung metastases only after four months from the operation. We report a rare case of thyroid MEC which had an aggressive behavior and poor prognosis. This case is a precious in that thyroid MEC occurred during observation of PC and suggests a possibility of the transformation from PC to MEC.
A Novel Internal Dual-Polarized EBG Antenna for Indoor Reception of UHF Terrestrial Digital TV Broadcasting
Authors: Sanad Mohamed , Hassan Noha
Published: August 2012

A novel internal antenna has been developed for indoor reception of UHF terrestrial digital TV broadcasting. The overall size of some configurations of the new antenna is less than 2 cm3, and its weight is less than 1 gm. It is made of a flexible material that can be bent or folded and shaped in any form. It is an unbalanced resonant antenna that does not need a matching circuit. The new antenna can be fully embedded inside TV sets or portable computers. It has a bandwidth of about 68%. Thus, it can also cover the bands of GSM and CDMA, which is advantageous in case of portable computers. The new antenna is linearly polarized. It can be easily modified to be dual polarized by combining two orthogonal antennas with one or two feed points. The overall efficiency of some configurations of the new indoor digital TV receiving antenna is more than 80%, and its peak gain is about 2 dBi over the whole UHF band. The peak gain can be increased to more than 5 dBi by adding EBG (electromagnetic bandgap) structures. The EBG structure also increases the efficiency to around 90%.
Self-Optimization of Coverage and Capacity in LTE Networks Based on Central Control and Decentralized Fuzzy Q-Learning
Authors: Li Jingyu , Zeng Jie , Su Xin , Luo Wei , Wang Jing
Published: August 2012

To reduce capital expenditures (CAPEX) and operational expenditures (OPEX) in network operations, self-organizing network (SON) has been introduced as a key part of long-term-evolution (LTE) system. Self-optimization of coverage and capacity is one of the most important tasks in the context of SON. This paper proposes a central control mechanism that utilizes the fuzzy Q-learning algorithm in a decentralized fashion for this task. In our proposed approach, each eNB is a learning agent that tries to optimize its antenna downtilt automatically using information from its own and its neighboring cells, and the initialization and the termination of the optimization processes of all agents are in the control of the central entity. The simulation results verify that our proposed approach can achieve remarkable performance enhancement as well as fast convergence, indicating that it is able to meet different levels of demands defined by 3GPP for coverage and capacity optimization.
The Role of Usability in Business-to-Business E-Commerce Systems: Predictors and Its Impact on User's Strain and Commercial Transactions
Authors: Konradt Udo , Lückel Lüder , Ellwart Thomas
Published: August 2012

This study examines the impact of organizational antecedences (i.e., organizational support and information policy) and technical antecedences (i.e., subjective server response time and objective server response time) to perceived usability, perceived strain, and commercial transactions (i.e. purchases) in business-to-business (B2B) e-commerce. Data were gathered from a web-based study with 491 employees using e-procurement bookseller portals. Structural equation modeling results revealed positive relationships of organizational support and information policy, and negative relationships of subjective server response time to usability after controlling for users' age, gender, and computer experience. Perceived usability held negative relationships to perceived strain and fully mediated the relation between the three significant antecedences and perceived strain while purchases were not predicted. Results are discussed in terms of theoretical implications and consequences for successfully designing and implementing B2B e-commerce information systems.
Semilocal Convergence Analysis for Inexact Newton Method under Weak Condition
Authors: Xu Xiubin , Xiao Yuan , Liu Tao
Published: August 2012

Under the hypothesis that the first derivative satisfies some kind of weak Lipschitz conditions, a new semilocal convergence theorem for inexact Newton method is presented. Unified convergence criteria ensuring the convergence of inexact Newton method are also established. Applications to some special cases such as the Kantorovich type conditions and γ‐Conditions are provided and some well‐known convergence theorems for Newton′s method are obtained as corollaries.
Selective Extraction of Organic Contaminants from Soil Using Pressurised Liquid Extraction
Authors: Osman Rozita , Saim Norashikin
Published: August 2012

This study focuses on the application of sorbents in pressurised liquid extraction (PLE) cell to establish a selective extraction of a variety of organic contaminants (polycyclic aromatic hydrocarbons (PAHs), chlorpyrifos, phenol, pentachlorophenol, and sterols) from soil. The selectivity and efficiency of each sorbent depend on the properties of the material, extracting solvent, capacity factor, organic compounds of interest, and PLE operating parameters (temperature, pressure, and extraction time). Several sorbents (silica, alumina, and Florisil) were evaluated and with the proper choice of solvents, polar and nonpolar compounds were successfully separated in two fractions. Nonpolar compounds (PAHs, chlorpyrifos, and pentachlorophenol) were recovered in the first fraction using a polar sorbent such as Florisil or alumina, and n‐hexane as eluting solvent, while more polar compounds (phenol and sterols) were recovered in the second fraction using methanol. Silica (5 g) was found to be effective for selective extraction with the satisfactory recoveries for all compounds (PAHs from 87.1–96.2%, chlorpyrifos 102.9%, sterols from 93.7–100.5%, phenol 91.9%, and pentachlorophenol 106.2%). The efficiency and precision of this extraction approach and the existing EPA Method 3545 were compared.
BINOL Macrocycle Derivatives: Synthesis of New Dinaphthyl Sulfide Aza Oxa Thia Crowns (Lariats)
Authors: Shockravi Abbas , Mehdipour-Ataei Shahram , Rostami Esmael
Published: August 2012

In this research work, dinaphthyl sulfide diester was prepared from the reaction of 1,1′‐thiobis (2‐hydroxy naphthalene) and methylchloroacetate. Its aza‐macrocyclic derivative was synthesized from the reaction of dinaphthyl sulfide diester and diethylenetriamine. Lariats were prepared from the reaction of chloroamides (four derivatives) and initial macrocycle. Chloroamides were synthesized from the reaction of amines (aniline, benzylamine, 8‐amino quinoline and 4‐amino azobenzene) and chloroacetyl chloride. All the materials were identified by IR, 1H NMR, 13C NMR, and mass spectroscopies, and elemental analysis.
Superior Efficacy of a Combined Epigenetic Therapy against Human Mantle Cell Lymphoma Cells
Authors: Fiskus Warren , Rao Rekha , Balusu Ramesh , Ganguly Siddhartha , Tao Jianguo , Sotomayor Eduardo , Mudunuru Uma , Smith Jacqueline E. , Hembruff Stacey L. , Atadja Peter , Marquez Victor E. , Bhalla Kapil
Published: August 2012

Purpose: A deregulated epigenome contributes to the transformed phenotype of mantle cell lymphoma (MCL). This involves activity of the polycomb repressive complex (PRC) 2, containing three core proteins, EZH2, SUZ12, and EED, in which the SET domain of EZH2 mediates the histone methyltransferase activity. We determined the effects of 3-deazaneplanocin A (DZNep), an S-adenosylhomocysteine hydrolase inhibitor, and/or pan-histone deacetylase inhibitor panobinostat (PS) on cultured and primary MCL cells.

Experimental Design: Following treatment with DZNep and/or PS, apoptosis and the levels and activity of EZH2 and PRC2 proteins in cultured and primary MCL cells were determined.

Results: Treatment with DZNep depleted EZH2, SUZ12, and 3MeK27H3 in the cultured human MCL cells. DZNep also increased expression of p21, p27, and FBXO32, whereas it depleted Cyclin D1 and Cyclin E1 levels in MCL cells. In addition, DZNep treatment induced cell-cycle arrest and apoptosis in cultured and primary MCL cells. Furthermore, as compared with treatment with each agent alone, cotreatment with DZNep and PS caused greater depletion of EZH2, SUZ12, 3MeK27H3, and Cyclin D1 levels, whereas it induced greater expression of FBXO32, p16, p21, and p27. Combined treatment with DZNep and PS synergistically induced apoptosis of cultured and primary MCL cells while relatively sparing normal CD34 + cells. Cotreatment with DZNep and PS also caused significantly greater inhibition of tumor growth of JeKo-1 xenografts in NOD/SCID mice.

Conclusions: These preclinical in vitro and in vivo findings show that cotreatment with DZNep and PS is an active combined epigenetic therapy worthy of further in vivo testing against MCL. Clin Cancer Res; 18(22); 6227–38. ©2012 AACR.
Intraoperative Near-Infrared Imaging of Surgical Wounds after Tumor Resections Can Detect Residual Disease
Authors: Madajewski Brian , Judy Brendan F. , Mouchli Anas , Kapoor Veena , Holt David , Wang May D. , Nie Shuming , Singhal Sunil
Published: August 2012

Purpose: Surgical resection remains the most effective therapy for solid tumors worldwide. The most important prognostic indicator for cure following cancer surgery is a complete resection with no residual disease. However, intraoperative detection of retained cancer cells after surgery is challenging, and residual disease continues to be the most common cause of local failure. We hypothesized that visual enhancement of tumors using near-infrared imaging could potentially identify tumor deposits in the wound after resection.

Experimental Design: A small animal model of surgery and retained disease was developed. Residual tumor deposits in the wound were targeted using an U.S. Food and Drug Administration–approved imaging agent, indocyanine green, by the enhanced permeability and retention effect. A novel handheld spectrometer was used to optically visualize retained disease after surgery.

Results: We found residual disease using near-infrared imaging during surgery that was not visible to the naked eye or micro-CT. Furthermore, examination of tumor nodules was remarkably precise in delineating margins from normal surrounding tissues. This approach was most successful for tumors with increased neovasculature.

Conclusions: The results suggest that near-infrared examination of the surgical wound after curative resection can potentially enable the surgeon to locate residual disease. The data in this study is the basis of an ongoing Phase I/II clinical trial in patients who undergo resection for lung and breast cancer. Clin Cancer Res; 18(20); 5741–51. ©2012 AACR.
IDO Expression in Brain Tumors Increases the Recruitment of Regulatory T Cells and Negatively Impacts Survival
Authors: Wainwright Derek A. , Balyasnikova Irina V. , Chang Alan L. , Ahmed Atique U. , Moon Kyung-Sub , Auffinger Brenda , Tobias Alex L. , Han Yu , Lesniak Maciej S.
Published: August 2012

Purpose: Glioblastoma multiforme (GBM) is an aggressive adult brain tumor with a poor prognosis. One hallmark of GBM is the accumulation of immunosuppressive and tumor-promoting CD4+FoxP3+GITR+ regulatory T cells (Tregs). Here, we investigated the role of indoleamine 2,3 dioxygenase (IDO) in brain tumors and the impact on Treg recruitment.

Experimental Design: To determine the clinical relevance of IDO expression in brain tumors, we first correlated patient survival to the level of IDO expression from resected glioma specimens. We also used novel orthotopic and transgenic models of glioma to study how IDO affects Tregs. The impact of tumor-derived and peripheral IDO expression on Treg recruitment, GITR expression, and long-term survival was determined.

Results: Downregulated IDO expression in glioma predicted a significantly better prognosis in patients. Coincidently, both IDO-competent and deficient mice showed a survival advantage bearing IDO-deficient brain tumors, when compared with IDO-competent brain tumors. Moreover, IDO deficiency was associated with a significant decrease in brain-resident Tregs, both in orthotopic and transgenic mouse glioma models. IDO deficiency was also associated with lower GITR expression levels on Tregs. Interestingly, the long-term survival advantage conferred by IDO deficiency was lost in T-cell–deficient mice.

Conclusions: These clinical and preclinical data confirm that IDO expression increases the recruitment of immunosuppressive Tregs that lead to tumor outgrowth. In contrast, IDO deficiency decreases Treg recruitment and enhances T-cell–mediated tumor rejection. Thus, the data suggest a critical role for IDO-mediated immunosuppression in glioma and support the continued investigation of IDO–Treg interactions in the context of brain tumors. Clin Cancer Res; 18(22); 6110–21. ©2012 AACR.
Thymic Stromal Lymphopoietin: A Promising Therapeutic Target for Allergic Diseases
Authors: Wang W.L. , Li H.Y. , Zhang M.S. , Gao P.S. , He S.H. , Zheng T. , Zhu Z. , Zhou L.F.
Published: August 2012

Thymic stromal lymphopoietin (TSLP), an interleukin 7-like cytokine, can trigger dendritic cell (DC)-mediated T-helper type 2 (Th2) inflammatory responses. Recent evidence demonstrates that cytokines TSLP and OX40 (CD134)/OX40 ligand seem to be important players in the maintenance of Th2 memory pool in the pathogenesis of asthma. Accumulating data reveal that the pathogenic T cells involved in asthma are likely to be inflammatory Th2 cells. TSLP is involved in the development of asthma through crosstalk with nuclear factor NF-ĸB. Progression of skin fibrosis in atopic dermatitis occurs via TSLP/TSLP receptor. TSLP-mediated dermal inflammation aggravates experimental allergic asthma. Also, TSLP polymorphisms are associated with susceptibility to asthma, atopic dermatitis, and eczema herpeticum. These findings suggest a master switch of TSLP in the initiation of allergic and adaptive inflammation through innate pathways at the epithelial cell-DC interface. The TSLP pathway is therefore a promising target for immunotherapy of allergic diseases.
Infrequent Manifestations of Kabuki Syndrome in a Patient with Novel MLL2 Mutation
Authors: Zarate Y.A. , Zhan H. , Jones J.R.
Published: August 2012

We present a case of a 9-month-old Hispanic female with Kabuki syndrome with some infrequent manifestations including a single umbilical artery, butterfly vertebrae, a small larynx, a preauricular pit, microtia with internal ear abnormalities, abnormal calcium metabolism, premature thelarche, neonatal/persistent hypoglycemia and eventration of the diaphragm. She was found to have a previously unreported nonsense MLL2 mutation. This is the first case that includes all such findings occurring simultaneously that was genotyped.
Nrf2-Keap1 Antioxidant Defense and Cell Survival Signaling Are Upregulated by 17β-Estradiol in Homocysteine-Treated Dopaminergic SH-SY5Y Cells
Authors: Chen Cheng-Sheng , Tseng Yu-Ting , Hsu Ya-Yun , Lo Yi-Ching
Published: August 2012

Background and Aims: A recent neuroimaging study discovered the neurotoxicity effects of homocysteine (Hcy), which is only seen in elderly women. Estrogens exert a variety of actions on brain function that influence cognitive function, mood, and neuroprotection. The Kelch-like ECH-associated protein 1 (Keap1)/nuclear factor erythroid 2-related factor 2 (Nrf2) antioxidant defense pathway has been well-known to afford neuroprotection. Here, we first demonstrate the roles of Nrf2-Keap1 in 17β-estradiol (E2) cytoprotection and Hcy toxicity and the protective mechanisms of E2 on Hcy cytotoxicity in human dopaminergic SH-SY5Y cells. Methods: Cell viability was determined by trypan blue method. Protein expression was determined by Western blot analysis. Superoxide dismutase (SOD) activity was determined by ELISA. Reactive oxygen species (ROS) production was determined by flow cytometry. Results: In Hcy-treated SH-SY5Y cells, E2 increased cell viability, attenuated ROS production, activated Akt signaling and inhibited glycogen synthase kinase-3β (GSK-3β), a kinase known to participate in neurodegeneration. Moreover, E2 treatment led to Nrf2 dissociation from Keap1, the main negative regulator of Nrf2 activity in the cytoplasm, and increased the protein level of Nrf2 in the nucleus, with a significant increase in HO-1 expression and SOD activity in Hcy-treated cells. E2-induced Nrf2 activation was attenuated by the PI3K inhibitor LY294002 and the estrogen receptor antagonist ICI 182,780. Further, E2 decreased Hcy-induced apoptotic death by upregulating the antiapoptotic protein Bcl-2, decreasing cytochrome c release from mitochondria, and attenuating apoptotic cascade activation (Bax, caspase-9, and caspase-3). Conclusion: E2 activates cell survival signaling and Nrf2-Keap1 antioxidant defense pathway and attenuates Hcy cytotoxicity.
Correlated Evolution of Gonadotropin-Releasing Hormone and Gonadotropin-Inhibitory Hormone and Their Receptors in Mammals
Authors: Tiwary Basant K.
Published: August 2012

Background: Evolutionary rate variation in genes (proteins) is manifested both within the species (genome) and between the species (genomes). However, the interdependent components of a biological system in form of a gene or a protein are expected to evolve in a correlated manner under a common functional constraint. Methods: The phylogenetic analysis and correlation analysis of gonadotropin-releasing hormone (GnRH) and gonadotropin-inhibitory hormone (GnIH) and their receptors (GnRHR and GnIHR) was conducted along with other control neuropeptides. Results: Both neuropeptides and their receptors regulating the reproductive neuroendocrine axis in vertebrates exhibited a correlated evolution under a common physiological constraint to regulate the release of gonadotropin. This result supports a coordinated substitution of amino acids in the GnRH and the GnIH neuropeptides along with their receptors in terms of similar evolutionary rates and distances with similar nucleotide composition of genes. Conclusion: This is the first demonstration of the correlated evolution of two components of an endocrine system regulating the release of gonadotropin which are acting in concert for successful reproduction.
Role of Phospholipid Oxidation Products in Atherosclerosis
Authors: Lee Sangderk , Birukov Konstantin G. , Romanoski Casey E. , Springstead James R. , Lusis Aldons J. , Berliner Judith A.
Published: August 2012

There is increasing clinical evidence that phospholipid oxidation products (Ox-PL) play a role in atherosclerosis. This review focuses on the mechanisms by which Ox-PL interact with endothelial cells, monocyte/macrophages, platelets, smooth muscle cells, and HDL to promote atherogenesis. In the past few years major progress has been made in identifying these mechanisms. It has been recognized that Ox-PL promote phenotypic changes in these cell types that have long-term consequences for the vessel wall. Individual Ox-PL responsible for specific cellular effects have been identified. A model of the configuration of bioactive truncated Ox-PL within membranes has been developed that demonstrates that the oxidized fatty acid moiety protrudes into the aqueous phase, rendering it accessible for receptor recognition. Receptors and signaling pathways for individual Ox-PL species are now determined and receptor independent signaling pathways identified. The effects of Ox-PL are mediated both by gene regulation and transcription independent processes. It has now become apparent that Ox-PL affects multiple genes and pathways, some of which are proatherogenic and some are protective. However, at concentrations that are likely present in the vessel wall in atherosclerotic lesions, the effects promote atherogenesis. There have also been new insights on enzymes that metabolize Ox-PL and the significance of these enzymes for atherosclerosis. With the knowledge we now have of the regulation and effects of Ox-PL in different vascular cell types, it should be possible to design experiments to test the role of specific Ox-PL on the development of atherosclerosis.