bluuebunny/crossref_metadata_2025 huggingface dataset:
A Recurrent Neural Network for Nonlinear Fractional Programming
Authors: Zhang Quan-Ju , Lu Xiao Qing
Published: September 2012

This paper presents a novel recurrent time continuous neural network model which performs nonlinear fractional optimization subject to interval constraints on each of the optimization variables. The network is proved to be complete in the sense that the set of optima of the objective function to be minimized with interval constraints coincides with the set of equilibria of the neural network. It is also shown that the network is primal and globally convergent in the sense that its trajectory cannot escape from the feasible region and will converge to an exact optimal solution for any initial point being chosen in the feasible interval region. Simulation results are given to demonstrate further the global convergence and good performance of the proposing neural network for nonlinear fractional programming problems with interval constraints.
Bioelectric State and Cell Cycle Control of Mammalian Neural Stem Cells
Authors: Aprea Julieta , Calegari Federico
Published: September 2012

The concerted action of ion channels and pumps establishing a resting membrane potential has been most thoroughly studied in the context of excitable cells, most notably neurons, but emerging evidences indicate that they are also involved in controlling proliferation and differentiation of nonexcitable somatic stem cells. The importance of understanding stem cell contribution to tissue formation during embryonic development, adult homeostasis, and regeneration in disease has prompted many groups to study and manipulate the membrane potential of stem cells in a variety of systems. In this paper we aimed at summarizing the current knowledge on the role of ion channels and pumps in the context of mammalian corticogenesis with particular emphasis on their contribution to the switch of neural stem cells from proliferation to differentiation and generation of more committed progenitors and neurons, whose lineage during brain development has been recently elucidated.
Quantitative Comparison of Five Different Photosensitizers for Use in a Photopolymer
Authors: Qi Yue , Gleeson Michael R. , Guo Jinxin , Gallego Sergi , Sheridan John T.
Published: September 2012

Several studies of the time varying photon absorption effects, which occur during the photoinitiation process involving in photopolymer materials, have been presented. Three primary mechanisms have been identified: (i) the dye absorption, (ii) recovery, and (iii) bleaching. Based on an analysis of these mechanisms, the production of primary radicals can be physically described and modelled. In free radical photopolymerization systems, the excited dye molecules induce the production of the primary radicals, R•, which are key in determining how many monomers are polymerized. This, in turn, is closely related to the refractive index modulation formed during holographic recording. In this paper, to avoid the complexities involved in estimating the rate constant of intersystem crossing, kst, in going from the excited singlet state dye to the excited triplet state dye, we introduce two rates, kaS and kaT these are the proposed rate constants of photon absorption in going from the ground state to the singlet and triplet states, respectively. Using the resulting model, four kinds of Xanthene dyes: Erythrosin B; Eosin Y; Phloxine B, Rose Bengal, and one Thiazine dye: Methylene Blue, are experimentally characterised for use in an AA/PVA photopolymer.
Cyanuric Chloride‐Catalyzed Michael Addition of Indoles to Nitroolefins under Solvent‐Free Conditions
Authors: Yang Xiao Juan , Jing Yun
Published: September 2012

Cyanuric chloride is an inexpensive, efficient, and mild catalyst for the Michael addition of indoles to nitroolefins at 70°C under solvent‐free conditions. The simple experimental procedure, solvent‐free reaction conditions, utilization of an inexpensive and readily available catalyst, short period of conversion, and excellent yields are the advantages of the present method.
Temporal Molecular and Biological Assessment of an Erlotinib-Resistant Lung Adenocarcinoma Model Reveals Markers of Tumor Progression and Treatment Response
Authors: Weaver Zoë , Difilippantonio Simone , Carretero Julian , Martin Philip L. , El Meskini Rajaa , Iacovelli Anthony J. , Gumprecht Michelle , Kulaga Alan , Guerin Theresa , Schlomer Jerome , Baran Maureen , Kozlov Serguei , McCann Thomas , Mena Salvador , Al-Shahrour Fatima , Alexander Danny , Wong Kwok-Kin , Van Dyke Terry
Published: September 2012

Patients with lung cancer with activating mutations in the EGF receptor (EGFR) kinase, who are treated long-term with tyrosine kinase inhibitors (TKI), often develop secondary mutations in EGFR associated with resistance. Mice engineered to develop lung adenocarcinomas driven by the human EGFR T790M resistance mutation are similarly resistant to the EGFR TKI erlotinib. By tumor volume endpoint analysis, these mouse tumors respond to BIBW 2992 (an irreversible EGFR/HER2 TKI) and rapamycin combination therapy. To correlate EGFR-driven changes in the lung with response to drug treatment, we conducted an integrative analysis of global transcriptome and metabolite profiling compared with quantitative imaging and histopathology at several time points during tumor progression and treatment. Responses to single-drug treatments were temporary, whereas combination therapy elicited a sustained response. During tumor development, metabolomic signatures indicated a shift to high anabolic activity and suppression of antitumor programs with 11 metabolites consistently present in both lung tissue and blood. Combination drug treatment reversed many of the molecular changes found in tumored lung. Data integration linking cancer signaling networks with metabolic activity identified key pathways such as glutamine and glutathione metabolism that signified response to single or dual treatments. Results from combination drug treatment suggest that metabolic transcriptional control through C-MYC and SREBP, as well as ELK1, NRF1, and NRF2, depends on both EGFR and mTORC1 signaling. Our findings establish the importance of kinetic therapeutic studies in preclinical assessment and provide in vivo evidence that TKI-mediated antiproliferative effects also manifest in specific metabolic regulation. Cancer Res; 72(22); 5921–33. ©2012 AACR.
Endoplasmic Reticulum-Derived Multilamellar Bodies in Oocytes of Mouse Follicle Cultures under Oxidized Low-Density Lipoprotein Treatment
Authors: Spanel-Borowski Katharina , Nowicki Marcin , Borlak Juergen , Trapphoff Tom , Eichenlaub-Ritter Ursula
Published: September 2012

Objective: Multilamellar bodies associated with an organized endoplasmic reticulum (ER) arise in various somatic cell types, and a subtype called multivesicular bodies is described in oocytes. Both entities, so far undetermined in significance, may occur in oocytes of follicles under oxidative stress. In preovulatory follicles, oxidative stress appears to be caused by oxidized low-density lipoprotein (ox-LDL). Method: Cultures of preantral mouse follicles were treated with 100 µg/ml ox-LDL or normal LDL (n-LDL) for 12–48 h or for 12 days during antral follicle growth followed by in vitro ovulation and harvest of cumulus oophorus complexes (COCs) with metaphase II (MII) oocytes on day 13. Preantral follicles, COCs, or MII oocytes were immunostained with anti-tubulin antibody or stained with actin-binding phalloidin for confocal microscopy. Ultrathin sections were prepared for electron microscopy. Results: Preantral follicles exposed to n-LDL or ox-LDL developed normally, and MII oocytes in COCs possessed normal spindles with well-aligned chromosomes. In contrast, treated cumulus cells underwent apoptosis. Only the ox-LDL-treated preantral follicle oocytes showed ER-derived multilamellar bodies (EMBs) of type I, consisting of rough ER membranes for the envelope. The MII oocytes of COCs showed type II EMBs consisting of smooth/vesicular ER and were more prominent after ox-LDL than after n-LDL exposure. Degenerating mitochondria were prominent in oocytes of the ox-LDL group and judged as a sign of oxidative stress. Conclusion: Oxidative stress presumably induces damage of proteins and organelles in the oocytes. The EMBs might sequester the damaged structures for oocyte survival. Thus, EMBs could represent a novel form of autophagy.
Somatostatin Receptor Types 1 and 2 in the Developing Mammalian Cochlea
Authors: Bodmer Daniel , Brand Yves , Radojevic Vesna
Published: September 2012

The neuropeptide somatostatin (SST) exerts several important physiological actions in the adult central nervous system through interactions with membrane-bound receptors. Transient expression of SST and its receptors has been described in several brain areas during early ontogeny. It is therefore believed that SST may play a role in neural maturation. The present study provides the first evidence for the developmental expression of SST receptors in the mammalian cochlea, emphasizing their possible roles in cochlear maturation. In the developing mouse cochlea, cells immunoreactive to somatostatin receptor 1 (SSTR1) and somatostatin receptor 2 (SSTR2) were located in the embryonic cochlear duct on Kolliker’s organ as early as embryonic day (E) 14 (E14). At E17, the expression of both receptors was high and already located at the hair cells and supporting cells along the length of the cochlear duct, which have become arranged into the characteristic pattern for the organ of Corti (OC) at this stage. At birth, SSTR1- and SSTR2-containing cells were only localized in the OC. In general, immunoreactivity for both receptors increased in the mouse cochlea from postnatal day (P) 0 (P0) to P10; the majority of immunostained cells were inner hair cells, outer hair cells, and supporting cells. Finally, a peak in the mRNA and protein expression of both receptors is present near the time when they respond to physiological hearing (i.e., hearing of airborne sound) at P14. At P21, SSTR1 and SSTR2 levels decrease dramatically. A similar developmental pattern was observed for SSTR1 and SSTR2 mRNA, suggesting that the expression of the SSTR1 and SSTR2 genes is controlled at the transcriptional level throughout development. In addition, we observed reduced levels of phospho-Akt and total Akt in SSTR1 knockout and SSTR1/SSTR2 double-knockout mice compared with wild-type mice. We know from previous studies that Akt is involved in hair cell survival. Taken together, the dynamic nature of SSTR1 and SSTR2 expression at a time of major developmental changes in the cochlea suggests that SSTR1 and SSTR2 (and possibly other members of this family) are involved in the maturation of the mammalian cochlea.
Consequences of Stopping and Restarting Leptin in an Adolescent with Lipodystrophy
Authors: Kamran F. , Rother K.I. , Cochran E. , Safar Zadeh E. , Gorden P. , Brown R.J.
Published: September 2012

Background/Aims: Lipodystrophy encompasses a group of rare disorders characterized by deficiency of adipose tissue resulting in hypoleptinemia, and metabolic abnormalities including insulin resistance, diabetes, dyslipidemia, and nonalcoholic steatohepatitis. Leptin replacement effectively ameliorates these metabolic derangements. We report effects of leptin discontinuation and resumption in a child with acquired generalized lipodystrophy. Methods: Intermittent treatment with leptin with follow-up over 5 years. Results: Pretreatment metabolic abnormalities included insulin resistance, hypertriglyceridemia and steatohepatitis. Leptin was started at the age of 10 years. After 2 years, the family requested discontinuation of leptin due to lack of visible physical changes. Nine months later, worsened metabolic abnormalities and arrest of pubertal development were observed. Leptin was restarted, followed by improvements in metabolic parameters. Laboratory changes (before vs. 6 months after restarting leptin) were: fasting glucose from 232 to 85 mg/dl, insulin from 232 to 38.9 µU/ml, HbA1c from 7.5 to 4.8%, triglycerides from 622 to 96 mg/dl, ALT from 229 to 61 U/l, AST from 91 to 18 U/l, and urine protein:creatinine ratio from 5.4 to 0.3. Progression of puberty was observed 1 year after restarting leptin. Conclusion: Initial leptin therapy likely prevented progression of metabolic abnormalities. Treatment discontinuation led to rapid metabolic decomposition and pubertal arrest. Reintroduction of leptin reversed metabolic abnormalities and allowed normal pubertal progression.
A Case of IgG4-Related Retroperitoneal Fibrosis Mimicking Renal Pelvic Cancer
Authors: Yoshino Tateki , Moriyama Hiroyuki , Fukushima Masayuki , Sanda Noriaki
Published: September 2012

IgG4-related sclerosing disease is a novel clinicopathological entity characterized by fibrosis, extensive infiltration of IgG4-positive plasma cells, and serum IgG4 elevation. This disorder includes a variety of diseases, such as autoimmune pancreatitis, retroperitoneal fibrosis, sialadenitis, thyroiditis, inflammatory abdominal aneurysm, tubulointerstitial nephritis, and inflammatory pseudotumor [World J Gastroenterol 2008;14:3948-3955]. A 71-year-old man visited our hospital with the complaint of left flank pain and gross hematuria. Computed tomography (CT) revealed left hydronephrosis and a thick retroperitoneal soft tissue mass around the ureteropelvic junction, suspicious of renal pelvic cancer. Urine cytology using a urine sample from the left renal pelvis was negative. On laboratory examination, serum levels of IgG and IgG4 were found to be elevated. The patient refused tumor biopsy. Therefore, he was treated with corticosteroid therapy on the basis of a clinical diagnosis with IgG4-related retroperitoneal fibrosis. Regression of the retroperitoneal mass as well as improvement of left hydronephrosis and decrease in serum IgG4 levels were accomplished. These effects strongly suggested that the present case was an IgG4-related retroperitoneal fibrosis. However, in this instance, since we could not completely rule out malignancies by biopsy, careful follow-up was necessary with these points in mind.
Pioglitazone Ameliorates Endothelial Dysfunction in Those with Impaired Glucose Regulation among the First-Degree Relatives of Type 2 Diabetes Mellitus Patients
Authors: Yu Xuemei , Chen Peihong , Wang Hongtao , Zhu Tong
Published: September 2012

Objective: To study the effects of pioglitazone on endothelial dysfunction of subjects with impaired glucose regulation (IGR) among the first-degree relatives of patients with type 2 diabetes mellitus (T2DM). Subjects and Methods: The first-degree relatives of T2DM patients were screened with oral glucose test and IGR was diagnosed. IGR subjects whose blood glucose was still above the level after 1-month exercise were randomized to receive pioglitazone (15 mg/day) or vehicle for 12 weeks. Endothelial function was assessed as endothelium-dependent and -independent vasodilation. Blood nitric oxide (NO), blood pressure, body mass index, insulin and serum lipids were also measured. Area under the curve of glucose (AUCglu) and insulin (AUCINS), homeostasis model assessment of insulin resistance (HOMA-IR), HOMA of β-cell function (HOMA-β) and early insulin secretion index (ΔI30/ΔG30) were calculated. Results: After pioglitazone treatment, fasting plasma, 2-hour plasma glucose, triglyceride (TG), fasting insulin, AUCglu, HOMA-β and HOMA-IR, 2-hour insulin, AUCINS and ΔI30/ΔG30 decreased. Endothelium-dependent vasodilation and NO were significantly improved in the treatment group. Furthermore, the changes of endothelium-dependent vasodilation were negatively correlated with changes in AUCINS but positively with NO and HOMA-β. Stepwise multivariate regression analysis showed that changes in NO and HOMA-β were both independent parameters for improvement of endothelial dysfunction. Conclusion: Pioglitazone decreased blood glucose and TG, increased insulin sensitivity, and ameliorated endothelial dysfunction of IGR subjects among the first-degree relatives of T2DM patients. Increased NO production may be associated with the improvement of endothelial dysfunction.
Antifibrotic Role of Captopril after Ureteral Injury
Authors: Pan Jiahua , Xue Wei , Chen Qi , Chen Yonghui , Chen Haige , Huang Yiran
Published: September 2012

Objectives: To evaluate the antifibrotic role of captopril during ureteral scarring in a New Zealand rabbit model. Materials and Methods: The tissue expression and the fluctuation of EGF, TGF-β, FN, Col Ia1, Col Ia2 and Col III of the impaired ureter and the contralateral normal ureter were investigated by RT-PCR. The histological changes of the specimens were studied. When the sensitive markers had been selected, 10 New Zealand rabbits were randomly assigned to a captopril group and a control group. The specimens were harvested 2 weeks after the injury and then the histological examination and RT-PCR were performed. Results: By RT-PCR screening, EGF, TGF-β, FN, Col Ia1 and Col Ia2 were found to be significantly related to ureteral scarring (p < 0.05) confirmed by histological examination. The peak level of EGF, TGF-β and Col Ia1 appeared at 2 weeks after the injury, while for Fn and Col Ia2 it was at 3 and 4 weeks after the injury. An obvious reduction of fibrotic scarring was observed in the captopril group. The expression of EGF, Fn and Col Ia2 in the captopril group was significantly lower than in the control group (p < 0.05) after the treatment. Conclusions: EGF, TGF-β, Col Ia1, Col Ia2 and FN seemed to have an important role in the ureteral scarring after injury. Captopril might partially inhibit the fibrotic process by blocking the EGF, Col Ia2 and FN pathway so that it could be a promising treatment after ureteral injury.
Remembering the Past and Imagining the Future in the Elderly
Authors: Schacter Daniel L. , Gaesser Brendan , Addis Donna Rose
Published: September 2012

Recent research has demonstrated commonalities between remembering past events and imagining future events. Behavioral studies have revealed that remembering the past and imagining the future depend on shared cognitive processes, whereas neuropsychological and neuroimaging studies have shown that many of the same brain regions are involved in both remembering the past and imagining the future. Here, we review recent cognitive and neuroimaging studies that examine remembering the past and imagining the future in elderly adults. These studies document significant changes in elderly adults' capacities to imagine future events that are correlated with their memory deficits; most strikingly, older adults tend to remember the past and imagine the future with less episodic detail than younger adults. These findings are in line with the constructive episodic simulation hypothesis [Schacter and Addis: Phil Trans R Soc B 2007;362:773-786], which holds that past and future events draw on similar information and rely on similar underlying processes, and that episodic memory supports the construction of future events by extracting and recombining stored information into a simulation of a novel event. At the same time, however, recent data indicate that non-episodic factors also contribute to age-related changes in remembering the past and imagining the future. We conclude by considering a number of questions and challenges concerning the interpretation of age-related changes in remembering and imagining, as well as functional implications of this research for everyday concerns of older adults.
Involvement of Patient Organisations in Research and Development of Orphan Drugs for Rare Diseases in Europe
Authors: Mavris M. , Le Cam Y.
Published: September 2012

Patients’ representatives have an increasingly present voice in all aspects of drug development from fundamental research through regulatory processes to health technology assessment. Although major advances have been made in raising awareness and increasing funding for rare diseases, important challenges remain in terms of best use of resources, coordinating efforts and improving policy. This article describes actions taken by rare disease patients’ organisations as well as initiatives at the national and European levels to promote research into rare diseases. A survey conducted by EURORDIS (European Organisation for Rare Diseases) on the support (financial and non-financial) provided by patients’ organisations in rare disease research is described as well as the involvement of patients’ representatives in regulatory processes for medicinal products at the European Medicines Agency. The importance of including patients’ groups in fundamental and clinical research as equal partners has become a fact that clearly contributes to the success of an application and the research conducted.
Child Maltreatment, Dating Perpetration of Physical Assault, and Cortisol Reactivity among Disadvantaged Female Adolescents
Authors: Linares L. Oriana , Shrout Patrick E. , Nucci-Sack Anne , Diaz Angela
Published: September 2012

Objective: Few studies have examined hypothalamic-pituitary-adrenal axis stress reactivity and its relationship to histories of child maltreatment and physical aggression. We examined the relation of a history of childhood sexual abuse (CSA) and perpetration of dating violence to patterns of cortisol change before (resting) and after (reactivity) exposure to a laboratory stressor. Methods: In a sample of 40 disadvantaged sexually active female adolescent patients (ages 14-17 years), we collected self-reports of lifetime child maltreatment (5 types) and past-year female perpetration of physical assault (PA) acts toward a romantic partner. We assessed changes in salivary cortisol trajectories during resting and reactivity phases following the viewing of a teen dating violence vignette. Results: Reports of CSA (CSA+ group) were associated with reports of perpetration of severe dating PA (PA+ group), but the relation of these reports to laboratory-assessed patterns of cortisol changes following the stressor was opposite. As compared with subjects without victimization or perpetration histories (referent group), the CSA+ group showed the most pronounced positive slope (reactivity), whereas the PA+ group showed the least positive slope following the laboratory stressor after the overlap between these groups was statistically adjusted. While showing less reactivity to the laboratory stressor, the PA+ group had higher levels of resting cortisol, which stayed high during reactivity as compared to the referent group. Conclusion: The laboratory paradigm to elicit neuroendocrine stress-related cortisol reactivity appears to be a promising tool for identifying altered cortisol physiology among female adolescents with mixed histories of CSA and perpetration of dating PA.
Comparison of Outcomes After Use of Biphasic or Monophasic Defibrillators Among Out-of-Hospital Cardiac Arrest Patients
Authors: Tanabe Seizan , Yasunaga Hideo , Ogawa Toshio , Koike Soichi , Akahane Manabu , Horiguchi Hiromasa , Hatanaka Tetsuo , Yokota Hiroyuki , Imamura Tomoaki
Published: September 2012

Background—

The use and popularity of the biphasic waveform defibrillator as a replacement for the monophasic waveform defibrillator are increasing, but it is unclear whether this can improve the rate of survival among out-of-hospital cardiac arrest patients. This study aimed to verify the hypothesis that the outcome of out-of-hospital cardiac arrest patients who received defibrillation shock with the biphasic waveform defibrillator was better than that of patients who received defibrillation shock with the monophasic defibrillator.

Methods and Results—

This prospective, nationwide, population-based, observational study included 21 172 out-of-hospital cardiac arrest patients with initial ventricular fibrillation or pulseless ventricular tachycardia from January 1, 2005, through December 31, 2007. Defibrillation shock was performed by monophasic defibrillator on 8224 (39%) patients and by biphasic defibrillator on 12 948 (61%) patients. The rate of survival at 1 month with minimal neurological impairment was 11.6% (951/8192) in the monophasic defibrillator group and 12.8% (1653/12 928) in the biphasic defibrillator group. Hierarchical logistic regression analysis using a generalized estimation equation showed no significant difference between the biphasic and monophasic groups in 1-month survival with minimal neurological impairment (adjusted odds ratio, 1.07; 95% confidence interval, 0.91–1.26;
P
=0.42). Confirmatory propensity score analyses showed similar results.

Conclusions—

Although monophasic defibrillators are being replaced by biphasic defibrillators, our nationwide population-based observational study failed to demonstrate a statistically significant association between defibrillation waveform and 1-month survival rate with minimal neurological impairment.
Genome Editing of Human Embryonic Stem Cells and Induced Pluripotent Stem Cells With Zinc Finger Nucleases for Cellular Imaging
Authors: Wang Yongming , Zhang Wendy Y. , Hu Shijun , Lan Feng , Lee Andrew S. , Huber Bruno , Lisowski Leszek , Liang Ping , Huang Mei , de Almeida Patricia E. , Won Jong H. , Sun Ning , Robbins Robert C. , Kay Mark A. , Urnov Fyodor D. , Wu Joseph C.
Published: September 2012

Rationale:

Molecular imaging has proven to be a vital tool in the characterization of stem cell behavior in vivo. However, the integration of reporter genes has typically relied on random integration, a method that is associated with unwanted insertional mutagenesis and positional effects on transgene expression.

Objective:

To address this barrier, we used genome editing with zinc finger nuclease (ZFN) technology to integrate reporter genes into a safe harbor gene locus (PPP1R12C, also known as AAVS1) in the genome of human embryonic stem cells and human induced pluripotent stem cells for molecular imaging.

Methods and Results:

We used ZFN technology to integrate a construct containing monomeric red fluorescent protein, firefly luciferase, and herpes simplex virus thymidine kinase reporter genes driven by a constitutive ubiquitin promoter into a safe harbor locus for fluorescence imaging, bioluminescence imaging, and positron emission tomography imaging, respectively. High efficiency of ZFN-mediated targeted integration was achieved in both human embryonic stem cells and induced pluripotent stem cells. ZFN-edited cells maintained both pluripotency and long-term reporter gene expression. Functionally, we successfully tracked the survival of ZFN-edited human embryonic stem cells and their differentiated cardiomyocytes and endothelial cells in murine models, demonstrating the use of ZFN-edited cells for preclinical studies in regenerative medicine.

Conclusion:

Our study demonstrates a novel application of ZFN technology to the targeted genetic engineering of human pluripotent stem cells and their progeny for molecular imaging in vitro and in vivo.
Tangent Bundle Curve Completion with Locally Connected Parallel Networks
Authors: Ben-Yosef Guy , Ben-Shahar Ohad
Published: September 2012

We propose a theory for cortical representation and computation of visually completed curves that are generated by the visual system to fill in missing visual information (e.g., due to occlusions). Recent computational theories and physiological evidence suggest that although such curves do not correspond to explicit image evidence along their length, their construction emerges from corresponding activation patterns of orientation-selective cells in the primary visual cortex. Previous theoretical work modeled these patterns as least energetic 3D curves in the mathematical continuous space [Formula: see text], which abstracts the mammalian striate cortex. Here we discuss the biological plausibility of this theory and present a neural architecture that implements it with locally connected parallel networks. Part of this contribution is also a first attempt to bridge the physiological literature on curve completion with the shape problem and a shape theory. We present completion simulations of our model in natural and synthetic scenes and discuss various observations and predictions that emerge from this theory in the context of curve completion.
Linear Coordinate-Descent Message Passing for Quadratic Optimization
Authors: Zhang Guoqiang , Heusdens Richard
Published: September 2012

In this letter, we propose a new message-passing algorithm for quadratic optimization. The design of the new algorithm is based on linear coordinate descent between neighboring nodes. The updating messages are in a form of linear functions as compared to the min-sum algorithm of which the messages are in a form of quadratic functions. As a result, the linear coordinate-descent (LiCD) algorithm transmits only one parameter per message as opposed to the min-sum algorithm, which transmits two parameters per message. We show that when the quadratic matrix is walk-summable, the LiCD algorithm converges. By taking the LiCD algorithm as a subroutine, we also fix the convergence issue for a general quadratic matrix. The LiCD algorithm works in either a synchronous or asynchronous message-passing manner. Experimental results show that for a general graph with multiple cycles, the LiCD algorithm has comparable convergence speed to the min-sum algorithm, thereby reducing the number of parameters to be transmitted and the computational complexity.
Bias Correction of Regional Climate Model Simulations in a Region of Complex Orography
Authors: Bordoy Roger , Burlando Paolo
Published: September 2012

This study presents a method to correct regional climate model (RCM) outputs using observations from automatic weather stations. The correction applies a nonlinear procedure, which recently appeared in the literature, to both precipitation and temperature on a monthly basis in a region of complex orography. To assess the temporal stability of such a correction, the correcting parameters of each variable are investigated using different time periods within the observational record. The RCM simulations used in this study to evaluate the bias-correction method are the publicly available “Reg-CM3” experiments from the Ensemble-Based Predictions of Climate Changes and Their Impacts (ENSEMBLES) project. They provide daily precipitation and temperature time series on a raster with spatial resolution of 0.22°. The analysis is performed in the Rhone catchment, located in southwestern Switzerland and characterized by highly complex orography. The results show that the nonlinear bias correction increases dramatically the accuracy not only of the RCM mean daily precipitation and temperature but also of values across the entire domain of the probability distribution. Moreover, the correction parameters seem to be reasonably independent from the sample used for their calibration, especially in the case of temperature. The good performance of the method over the considered mountainous region during the evaluation period points to the suitability of this technique for correcting RCM biases regardless of the stationarity of the climate and, therefore, also for future climate and in regions characterized by marked orography.
Zonal Momentum Balance in the Tropical Atmospheric Circulation during the Global Monsoon Mature Months
Authors: Yang Wenchang , Seager Richard , Cane Mark A.
Published: September 2012

In this paper, zonal momentum balances of the tropical atmospheric circulation during the global monsoon mature months (January and July) are analyzed in three dimensions based on the ECMWF Interim Re-Analysis (ERA-Interim). It is found that the dominant terms in the balance of the atmospheric boundary layer (ABL) in both months are the pressure gradient force, the Coriolis force, and friction. The nonlinear advection term plays a significant role only in the Asian summer monsoon regions within the ABL. In the upper troposphere, the pressure gradient force, the Coriolis force, and the nonlinear advection are the dominant terms. The transient eddy force and the residual force (which can be explained as convective momentum transfer over open oceans) are secondary, yet cannot be neglected near the equator. Zonal-mean equatorial upper-troposphere easterlies are maintained by the absolute angular momentum advection associated with the cross-equatorial Hadley circulation. Equatorial upper-troposphere easterlies over the Asian monsoon regions are also controlled by the absolute angular momentum advection but are mainly maintained by the pressure gradient force in January. The equivalent linear Rayleigh friction, which is widely applied in simple tropical models, is calculated and the corresponding spatial distribution of the local coefficient and damping time scale are estimated from the linear regression. It is found that the linear momentum model is in general capable of crudely describing the tropical atmospheric circulation dynamics, yet the caveat should be kept in mind that the friction coefficient is not uniformly distributed and is even negative in some regions.
An Investigation of Composite Dropsonde Profiles for Developing and Nondeveloping Tropical Waves during the 2010 PREDICT Field Campaign
Authors: Komaromi William A.
Published: September 2012

Composite dropsonde profiles are analyzed for developing and nondeveloping tropical waves in an attempt to improve the understanding of tropical cyclogenesis. These tropical waves were sampled by 25 reconnaissance missions during the 2010 Pre-Depression Investigation of Cloud-Systems in the Tropics (PREDICT) field campaign. Comparisons are made between mean profiles of temperature, mixing ratio, relative humidity, radial and tangential winds, relative vorticity, and virtual convective available potential energy (CAPE) for genesis and nongenesis cases. Genesis soundings are further analyzed in temporal progression to investigate whether significant changes in the thermodynamic or wind fields occur during the transition from tropical wave to tropical cyclone.

Significant results include the development of positive temperature anomalies from 500 to 200 hPa 2 days prior to genesis in developing waves. This is not observed in the nongenesis mean. Progressive mesoscale moistening of the column is observed within 150 km of the center of circulation prior to genesis. The genesis composite is found to be significantly moister than the nongenesis composite at the middle levels, while comparatively drier at low levels, suggesting that dry air is more detrimental to genesis when located at the middle levels. Time-varying tangential wind profiles reveal an initial delay in intensification, followed by an increase in organization 24 h pregenesis. The vertical evolution of relative vorticity, in addition to a warm-over-cold thermal structure, is more consistent with a top-down than a bottom-up genesis mechanism. Last, CAPE values are much greater for nongenesis than genesis profiles, indicating that greater instability does not necessarily favor genesis.
MJO Initiation in the Real-Time Multivariate MJO Index
Authors: Straub Katherine H.
Published: September 2012

Madden–Julian oscillation (MJO) initiation in the real-time multivariate MJO (RMM) index is explored through an analysis of observed case studies and composite events. Specific examples illustrate that both the dates of MJO initiation and the existence of the MJO itself can vary substantially among several well-known MJO indices, depending on whether the focus is on convection or circulation. Composites of “primary” MJO initiation events in which the RMM index rapidly increases in amplitude from a non-MJO state to an MJO state are presented and are supplemented by two case studies from the 1985/86 winter season. Results illustrate that, for primary MJO initiation events in the Indian Ocean (RMM phase 1), slowly eastward-propagating 850-hPa (200 hPa) easterly (westerly) anomalies over the Indian Ocean precede the amplification of the RMM index by at least 10 days, while suppressed convection over the western Pacific Ocean precedes the amplification by 5 days. These “local” Eastern Hemispheric predecessor signals are similar to those found in successive (well established) MJO events but are not captured by the global-scale RMM index because of their smaller zonal scale. The development of a primary MJO event is thus often transparent in the RMM index, since it occurs on scales smaller than zonal wavenumber 1, particularly in convection. Even when the RMM index is altered to respond to convection only, the same local precursor signals are found. Both composites and case studies suggest that, for primary MJO initiation events in the Indian Ocean, the development of global-scale circulation anomalies typically precedes the onset of large-scale deep convection.
Monitoring and Predicting the Intraseasonal Variability of the East Asian–Western North Pacific Summer Monsoon
Authors: Lin Hai
Published: September 2012

In this study, a new index is defined to capture the prominent northward propagation of the intraseasonal oscillation (ISO) in boreal summer in the East Asian and western North Pacific (EAWNP) region. It is based on the first two modes of empirical orthogonal function (EOF) analysis of the combined fields of daily anomalies of zonally averaged outgoing longwave radiation (OLR) and 850-hPa zonal wind (U850) in the EAWNP region. These two EOFs are well separated from the rest of the modes, and their principal components (PCs) capture the intraseasonal variability. They are nearly in quadrature in both space and time and their combination reasonably well represents the northward propagation of the ISO. As no future information beyond the current date is required as in conventional time filtering, this ISO index can be used in real-time applications. This index is applied to the output of the 24-yr historical hindcast experiment using the Global Environmental Multiscale (GEM) model of Environment Canada to evaluate the forecast skill of the ISO of the EAWNP summer monsoon.
EnKF Assimilation of High-Resolution, Mobile Doppler Radar Data of the 4 May 2007 Greensburg, Kansas, Supercell into a Numerical Cloud Model
Authors: Tanamachi Robin L. , Wicker Louis J. , Dowell David C. , Bluestein Howard B. , Dawson Daniel T. , Xue Ming
Published: September 2012

Mobile Doppler radar data, along with observations from a nearby Weather Surveillance Radar-1988 Doppler (WSR-88D), are assimilated with an ensemble Kalman filter (EnKF) technique into a nonhydrostatic, compressible numerical weather prediction model to analyze the evolution of the 4 May 2007 Greensburg, Kansas, tornadic supercell. The storm is simulated via assimilation of reflectivity and velocity data in an initially horizontally homogeneous environment whose parameters are believed to be a close approximation to those of the Greensburg supercell inflow sector. Experiments are conducted to test analysis sensitivity to mobile radar data availability and to the mean environmental near-surface wind profile, which was changing rapidly during the simulation period. In all experiments, a supercell with similar location and evolution to the observed storm is analyzed, but the simulated storm’s characteristics differ markedly. The assimilation of mobile Doppler radar data has a much greater impact on the resulting analyses, particularly at low altitudes (≤2 km), than modifications to the near-surface environmental wind profile. Differences in the analyzed updrafts, vortices, cold pool structure, rear-flank gust front structure, and observation-space diagnostics are documented. An analyzed vortex corresponding to the enhanced Fujita scale 5 (EF-5) Greensburg tornado is stronger and deeper in experiments in which mobile (higher resolution) Doppler radar data are included in the assimilation. This difference is linked to stronger analyzed horizontal convergence, which in turn is associated with increased stretching of vertical vorticity. Changing the near-surface wind profile appears to impact primarily the updraft strength, availability of streamwise vorticity for tilting into the vertical, and low-level vortex strength and longevity.
Rhetorics of Suffering
Authors: Simko Christina
Published: September 2012

Weber argued that human suffering creates the demand for theodicies: cultural vocabularies, religious or secular, that explain perceived injustices. This article combines an interpretive analysis of rhetoric commemorating the events of September 11, 2001 with an effort to construct generalizable cultural theory, demonstrating how the Weberian concept of theodicy adds to our understanding of commemorative rhetoric. In the case of September 11 commemorations, the theodicies deployed exhibit a clear fracture. Speakers at the Pentagon and in Shanksville, Pennsylvania, have taken a dualistic approach to the problem of theodicy, while speakers in Manhattan have taken a tragic approach. This variation can be explained through a four-part model that argues theodicies are structured by (1) events, (2) carrier groups, (3) audiences, and (4) genre memory. More broadly, I argue for explicit attention to theodicy in cultural sociology, demonstrating that the quest for theodicy is a crucial driving force behind the impulse to commemorate in the first place.
Plasma Matrix Metalloproteinase 9 Levels May Predict Endoleaks After Endovascular Aortic Aneurysm Repair
Authors: Antoniou George A. , Georgiadis George S. , Antoniou Stavros A. , Murray David , Smyth J. Vincent , Serracino-Inglott Ferdinand , Paraskevas Kosmas I.
Published: September 2012

A simple, noninvasive and cost-effective diagnostic test for the detection of endoleaks after endovascular aneurysm repair (EVAR) would complement (or even replace) current surveillance modalities. We reviewed the literature for studies correlating circulating levels of matrix metalloproteinases (MMPs)/tissue inhibitors of MMPs with the presence of endoleaks after EVAR. An electronic search of databases was performed to identify studies reporting circulating concentrations of MMPs in patients with and without an endoleak after EVAR. Four studies were identified. Patients with an endoleak had higher plasma MMP-9 levels compared with those without an endoleak. Two studies that also evaluated plasma MMP-3 levels after EVAR suggest that these levels may also be higher in patients with an endoleak. Preliminary evidence suggests that MMP-9 levels are increased in patients developing an endoleak after EVAR. Larger studies are required to confirm or refute our findings.
Coronary Artery Calcification Progression in Asymptomatic Individuals With Initial Score of Zero
Authors: Koulaouzidis G. , Charisopoulou D. , Maffrett S. , Tighe M. , Jenkins P. J. , McArthur T.
Published: September 2012

The aim of this study is to determine the progression of coronary artery calcification (CAC) using electron beam computed tomography (CT) when the initial CAC score (CACS) is zero and to determine the best interval to repeat a CAC scan. We studied 388 individuals with zero CACS (308 males; mean age: 48.8 ± 8.26 years) who underwent 2 consecutive CT scans in a period of at least 12 months apart. The interscan period was 2.99 ± 1.35 years (range: 1-6 years). Three-quarters of the individuals (75%) did not develop any CAC progression, 20.87% presented CAC progression of 1 to 10, 3.6% had 11 to 50, whereas only 0.51% had >50. The average time of new CAC development was 4.2 ± 1.1 years. Individuals with CAC progression presented higher incidence of hypertension, diabetes mellitus, hypercholesterolaemia and higer frequency of male gender than those with without CAC changes (p<0.02). No cardiac events occurred during the follow-up period.
Analysis of out-of-plane stresses in sandwich beams subjected to pure bending with large deflections
Authors: de la Cruz V Rodríguez , Caballero D Fernández , Mujika F , Muñoz-Guijosa JM
Published: September 2012

The classic strength of materials theory considers out-of-plane stresses in beams subjected to pure bending to be negligible. This work undertakes a theoretical analysis of this proposition by basing it on the development of the Airy’s functions in polar coordinates. The purpose of this research is studying the effect of this kind of stresses in structures fabricated with non-isotropic materials. Specifically, multi-component sandwich beams subjected to pure bending and large deflections have been studied. An analytical model is proposed that allows these out-of-plane stresses to be calculated according to the curvature change and other design parameters of the specific structure. The completed model was used to calculate the out-of-plane stresses for different design configurations, in order to study their effects. Finally, results are compared to a finite element model.
Ethnic, Gender, and Contact Differences in Intimacy Attitudes Toward Wheelchair Users
Authors: Marini Irmo , Wang Xiaohui , Etzbach Colleen A. , Del Castillo Alinka
Published: September 2012

Student attitudes toward having a relationship with a wheelchair user were explored. Participants initially selected one of six opposite gender head shots and subsequently viewed their selection’s whole body photograph in a wheelchair along with reading a short biography. Primarily undergraduate Hispanic and Caucasian students ( N = 810) were surveyed regarding their interest in potentially being friends, dating, or marrying a wheelchair user, with 66% indicating they would have no problem dating or marrying a wheelchair user. Chi-square tests of pairwise association, logistical regression, and test of proportional odds revealed significant differences, p = .001, between ethnicity, gender, type of relationship, and having had a prior disability relationship. Personal traits of intelligence, humor, kindness, and physical appearance were rated most highly. Those unwilling to date or marry their selection perceived the partner would require too much caregiving, social interaction awkwardness, inability to sexually perform, and the partner being sick often. Counselors can benefit from informing clients about intimacy misconceptions by role-playing and providing clients with insights regarding societal beliefs.
A Cross-Level Test of Empowerment and Process Influences on Members’ Informal Learning and Team Commitment
Authors: Kukenberger Michael R. , Mathieu John E. , Ruddy Thomas
Published: September 2012

Team effectiveness can be gauged not only by team-level outcomes but also in terms of influences on individual members. The authors present a two-sample cross-level model of individual informal learning and team commitment, as influenced by team-level processes and empowerment. In the first sample, they examine the impact of team-level constructs on individual outcomes, using 575 individuals from 80 teams in an international Fortune 500 manufacturing firm. Using a sample of 67 teams and 271 individual service engineers from a separate Fortune 500 business solutions organization, the authors further advance their model using a pre–post intervention design. Informal learning and commitment are shown to be positively impacted by team-level empowerment and processes, over and above individual predispositions and perceptions in both samples. In addition, changes in team empowerment and processes attributable to the intervention account for additional criterion variance. Implications are discussed in terms of both research and practice.