bluuebunny/crossref_metadata_2025 huggingface dataset:
Convergence of Returns on Chinese and Russian Stock Markets with World Markets: National and Sectoral Perspectives
Authors: Babecký Jan , Komárek Luboš , Komárková Zlatuše
Published: February 2013

Interest in examining the financial linkages of economies has increased in the wake of the 2008/9 global financial crisis. Applying the concepts of beta- and sigma-convergence of stock market returns, we assess changes over time in the degree of stock market integration of Russia and China with each other, as well as with respect to the United States, the Euro Area, and Japan. Our analysis is based on national and sectoral data spanning the period September 1995 to October 2010. Overall, we find evidence for gradually increasing convergence of stock market returns after the 1997 Asian financial crisis and the 1998 Russian financial crisis. Following a major disruption caused by the 2008/9 global financial crisis, the process of stock market return convergence resumes between Russia and China, as well as with world markets. Notably, the episode of sigma-divergence from the 2008/9 crisis is stronger for China than for Russia. We also find that the process of stock market return convergence and the impact of the recent crisis have not been uniform at the sectoral level, suggesting the potential for diversification of risk across sectors.
Inflation in China Increasingly Driven by Domestic Factors
Authors: Dreger Christian , Zhang Yanqun
Published: February 2013

The article investigates the determinants of consumer price inflation in China. While inflation has been entirely driven by international factors, such as food and energy prices, in the period preceeding the financial crisis, domestic drivers like monetary developments and nominal wages have become increasingly important since then. Due to tight trade linkages and the presence of Chinese firms in international production chains, the changing pattern is also relevant to other countries.
Prior Experience with Photostimulation Enhances Photo-Induced Reproductive Response in Female House Finches
Authors: Salvante Katrina G. , Dawson Alistair , Aldredge Robert A. , Sharp Peter J. , Sockman Keith W.
Published: February 2013

In vertebrates, reproductive output often increases with age. Unlike older birds, first-year photoperiodic birds lack experience with the reproductively stimulatory effects of long day lengths (photostimulation). We examined whether age-related differences in annual reproductive development could be partially attributed to previous experience with photostimulation in the photoperiodic house finch ( Carpodacus mexicanus). By manipulating photoperiod, we generated 2 groups of first-year females: a photo-experienced group that underwent 1 photoperiodically induced cycle of gonadal development and regression and a photo-naïve group exposed to long days since hatch. We transferred both groups from long to short days and then photostimulated and exposed them to male birdsong prior to sacrifice. Following concurrent photostimulation, both groups exhibited similar plasma luteinizing hormone surges and hypothalamic vasoactive intestinal polypeptide immunoreactivity. In contrast, hypothalamic gonadotropin-releasing hormone immunoreactivity and circulating vitellogenin levels were higher in photo-experienced birds, and yolk deposition occurred in only 2 females, both of which were photo-experienced. Our results demonstrate that photo-experience enhances some aspects of early photo-induced reproductive development and raise the hypothesis that photo-experience may account for at least some age-related variation in reproductive output.
Monozygotic Twin Differences in Non-shared Environmental Factors Associated with Chronotype
Authors: Barclay Nicola L. , Eley Thalia C. , Parsons Michael J. , Willis Thomas A. , Gregory Alice M.
Published: February 2013

Twin studies have highlighted that a large proportion of variability in chronotype is accounted for by individual-specific environmental factors (non-shared environmental influences). However, little research has aimed to identify specific non-shared environmental influences on chronotype. Although epidemiological studies have shed light on possible environmental influences on chronotype, a substantial amount of research has highlighted the importance of genetic influences on exposure toward specific environments, a process termed gene-environment correlation. It is possible that associations between the environment and chronotype are in part determined by genetics, rather than being purely environmental in origin. One way of exploring the contribution of purely non-shared environmental components on associations between chronotype and the environment is to use the monozygotic twin differences design. This design allows us to tease apart the influences of genetics and the environment to identify purely environmental components. One hundred eighty-nine monozygotic twin pairs (mean age 19.81 years, SD = 1.26, range = 18-22 years, 66.1% female) completed the Horne and Östberg Morningness-Eveningness Questionnaire as a measure of chronotype and questionnaires assessing the following candidate non-shared environmental influences: dependent and independent negative life events, educational attainment, employment status, relationship status, deviant peers, affiliation with deviant peers, general health, smoking, drug use, and alcohol use. Linear regression analyses indicated the presence of gene-environment correlation for the majority of associations between chronotype and candidate environmental influences. When controlling for genetic and shared environmental effects, within monozygotic twin-pair differences in chronotype were associated with within monozygotic twin-pair differences in dependent negative life events (β = −0.27, p < 0.001), educational attainment (β = −0.14, p < 0.05), smoking status (β = 0.22, p < 0.01), and drug use (β = −0.16, p < 0.01). These results suggest that some of the association between these variables is purely environmental in nature. The associations between the remaining environmental variables and chronotype, however, may be intertwined with underlying genetic factors. These findings add to our understanding of genetic and environmental mechanisms underlying the biological clock.
Drosophila Clock Neurons under Natural Conditions
Authors: Menegazzi Pamela , Vanin Stefano , Yoshii Taishi , Rieger Dirk , Hermann Christiane , Dusik Verena , Kyriacou Charalambos P. , Helfrich-Förster Charlotte , Costa Rodolfo
Published: February 2013

The circadian clock modulates the adaptive daily patterns of physiology and behavior and adjusts these rhythms to seasonal changes. Recent studies of seasonal locomotor activity patterns of wild-type and clock mutant fruit flies in quasi-natural conditions have revealed that these behavioral patterns differ considerably from those observed under standard laboratory conditions. To unravel the molecular features accompanying seasonal adaptation of the clock, we investigated Drosophila’s neuronal expression of the canonical clock proteins PERIOD (PER) and TIMELESS (TIM) in nature. We find that the profile of PER dramatically changes in different seasons, whereas that of TIM remains more constant. Unexpectedly, we find that PER and TIM oscillations are decoupled in summer conditions. Moreover, irrespective of season, PER and TIM always peak earlier in the dorsal neurons than in the lateral neurons, suggesting a more rapid molecular oscillation in these cells. We successfully reproduced most of our results under simulated natural conditions in the laboratory and show that although photoperiod is the most important zeitgeber for the molecular clock, the flies’ activity pattern is more strongly affected by temperature. Our results are among the first to systematically compare laboratory and natural studies of Drosophila rhythms.
Organizational Identity and Organizational Identification
Authors: Hodgkinson Gerard P.
Published: February 2013

Scholarly research directed toward the analysis of organizational identity and organizational identification is fragmented along disciplinary and subdisciplinary fault lines that mirror the current intellectual and social organization of the management and organization studies field. Adopting a critical realist design science perspective, the author challenges researchers to set aside their own identity concerns to embark on an ambitious program of work that capitalizes on the strengths of the alternative perspectives in play, with a view to generating insights that are truly greater than the sum of the parts. The imperative for doing so, at this critical juncture, is the need to address the pressing challenges that threaten to harm beyond repair the social harmony that is the bedrock of the world economy and society.
Quantitative analysis of persister fractions suggests different mechanisms of formation among environmental isolates of E. coli
Authors: Hofsteenge Niels , van Nimwegen Erik , Silander Olin K
Published: February 2013

Background

Bacterial persistence describes a phenomenon wherein a small subpopulation of cells is able to survive a challenge with high doses of an antibiotic (or other stressor) better than the majority of the population. Previous work has shown that cells that are in a dormant or slow-growing state are persistent to antibiotic treatment and that populations with higher fractions of dormant cells exhibit higher levels of persistence. These data suggest that a major determinant of the fraction of persisters within a population is the rate at which cells enter and exit from dormancy. However, it is not known whether there are physiological changes in addition to dormancy that influence persistence. Here, we use quantitative measurements of persister fractions in a set of environmental isolates of E. coli together with a mathematical model of persister formation to test whether a single general physiological change, such as cell dormancy, can explain the differences in persister phenotypes observed in different strains.

Results

If a single physiological change (e.g. cell dormancy) underlies most persister phenotypes, then strains should exhibit characteristic fractions of persister cells: some strains will consistently have high fractions of persisters (dormant cells), whereas others will have low fractions. Although we found substantial variation in the fraction of persisters between different environmental isolates of E. coli, these fractions were not correlated across antibiotics. Some strains exhibited high persister fractions in one antibiotic, but low persister fractions in a second antibiotic. Surprisingly, no correlation in persister fractions was observed between any two drugs, even for antibiotics with nearly identical modes of action (ciprofloxacin and nalidixic acid).

Conclusions

These data support the hypothesis that there is no single physiological change that determines the persistence level in a population of cells. Instead, the fraction of cells that survive antibiotic treatment (persist) depends critically on the specific antibiotic that is used, suggesting that physiological changes in addition to dormancy can underlie persister phenotypes.
Transcriptome analysis of embryo maturation in maize
Authors: Teoh Keat Thomas , Requesens Deborah Vicuna , Devaiah Shivakumar P , Johnson Daniel , Huang Xiuzhen , Howard John A , Hood Elizabeth E
Published: February 2013

Background

Maize is one of the most important crops in the world. With the exponentially increasing population and the need for ever increased food and feed production, an increased yield of maize grain (as well as rice, wheat and other grains) will be critical. Maize grain development is understood from the perspective of morphology, hormone responses, and storage reserve accumulation. This includes various studies on gene expression during embryo development and maturation but a global study of gene expression of the embryo has not been possible until recently. Transcriptome analysis is a powerful new tool that can be used to understand the genetic basis of embryo maturation.

Results

We undertook a transcriptomic analysis of normal maturing embryos at 15, 21 and 27 days after pollination (DAP), of one elite maize germplasm line that was utilized in crosses to transgenic plants. More than 19,000 genes were analyzed by this method and the challenge was to select subsets of genes that are vitally important to embryo development and maturation for the initial analysis. We describe the changes in expression for genes relating to primary metabolic pathways, DNA synthesis, late embryogenesis proteins and embryo storage proteins, shown through transcriptome analysis and confirmed levels of transcription for some genes in the transcriptome using qRT-PCR.

Conclusions

Numerous genes involved in embryo maturation have been identified, many of which show changes in expression level during the progression from 15 to 27 DAP. An expected array of genes involved in primary metabolism was identified. Moreover, more than 30% of transcripts represented un-annotated genes, leaving many functions to be discovered. Of particular interest are the storage protein genes, globulin-1, globulin-2 and an unidentified cupin family gene. When expressing foreign proteins in maize, the globulin-1 promoter is most often used, but this cupin family gene has much higher expression and may be a better candidate for foreign gene expression in maize embryos. Results such as these allow identification of candidate genes and promoters that may not otherwise be available for use. mRNA seq data archived in NCBI SRA; Accession number: ACC=SRA060791 subid=108584.
Single-cell-based system to monitor carrier driven cellular auxin homeostasis
Authors: Barbez Elke , Laňková Martina , Pařezová Markéta , Maizel Alexis , Zažímalová Eva , Petrášek Jan , Friml Jiří , Kleine-Vehn Jürgen
Published: February 2013

Background

Abundance and distribution of the plant hormone auxin play important roles in plant development. Besides other metabolic processes, various auxin carriers control the cellular level of active auxin and, hence, are major regulators of cellular auxin homeostasis. Despite the developmental importance of auxin transporters, a simple medium-to-high throughput approach to assess carrier activities is still missing. Here we show that carrier driven depletion of cellular auxin correlates with reduced nuclear auxin signaling in tobacco Bright Yellow-2 (BY-2) cell cultures.

Results

We developed an easy to use transient single-cell-based system to detect carrier activity. We use the relative changes in signaling output of the auxin responsive promoter element DR5 to indirectly visualize auxin carrier activity. The feasibility of the transient approach was demonstrated by pharmacological and genetic interference with auxin signaling and transport. As a proof of concept, we provide visual evidence that the prominent auxin transport proteins PIN-FORMED (PIN)2 and PIN5 regulate cellular auxin homeostasis at the plasma membrane and endoplasmic reticulum (ER), respectively. Our data suggest that PIN2 and PIN5 have different sensitivities to the auxin transport inhibitor 1-naphthylphthalamic acid (NPA). Also the putative PIN-LIKES (PILS) auxin carrier activity at the ER is insensitive to NPA in our system, indicating that NPA blocks intercellular, but not intracellular auxin transport.

Conclusions

This single-cell-based system is a useful tool by which the activity of putative auxin carriers, such as PINs, PILS and WALLS ARE THIN1 (WAT1), can be indirectly visualized in a medium-to-high throughput manner. Moreover, our single cell system might be useful to investigate also other hormonal signaling pathways, such as cytokinin.
Influence of personal and environmental factors on mental health in a sample of Austrian survivors of World War II with regard to PTSD: is it resilience?
Authors: Tran Ulrich S , Glück Tobias M , Lueger-Schuster Brigitte
Published: February 2013

Background

War-related traumata in childhood and young-adulthood may have long-lasting negative effects on mental health. The focus of recent research has shifted to examine positive adaption despite traumatic experiences, i.e. resilience. We investigated personal and environmental factors associated with resilience in a sample of elderly Austrians (N = 293) who reported traumatic experiences in early life during World War II and subsequent occupation (1945–1955).

Methods

After reviewing different concepts of resilience, we analysed our data in a 3-phased approach: Following previous research approaches, we first investigated correlates of PTSD and non-PTSD. Secondly, we compared a PTSD positive sample (sub-threshold and full PTSD, n = 42) with a matched control sample regarding correlates of resilience and psychometrically assessed resilience (CD-RISC). Thirdly, we examined factors of resilience, discriminating between psychologically healthy participants who were exposed to a specific environmental stressor (having lived in the Soviet zone of occupation during 1945–1955) from those who were not.

Results

A smaller number of life-time traumata (OR = 0.73) and a medium level of education (OR = 2.46) were associated with better outcome. Matched PTSD and non-PTSD participants differed in psychometrically assessed resilience mainly in aspects that were directly related to symptoms of PTSD. Psychologically healthy participants with an environmental stressor in the past were characterized by a challenge-oriented and humorous attitude towards stress.

Conclusions

Our results show no clear picture of factors constituting resilience. Instead, most aspects of resilience rather appeared to be concomitants or consequences of PTSD and non-PTSD. However, special attention should be placed on a challenge-oriented and humorous attitude towards stress in future definitions of resilience.
Identification of active Plasmodium falciparum calpain to establish screening system for Pf-calpain-based drug development
Authors: Soh Byoung Yul , Song Hyun-Ok , Lee Yoonji , Lee Junghyun , Kaewintajuk Kusuma , Lee Binna , Choi Yun-Young , Cho Jeong Hoon , Choi Sun , Park Hyun
Published: February 2013

Background

With the increasing resistance of malaria parasites to available drugs, there is an urgent demand to develop new anti-malarial drugs. Calpain inhibitor, ALLN, is proposed to inhibit parasite proliferation by suppressing haemoglobin degradation. This provides Plasmodium calpain as a potential target for drug development. Pf-calpain, a cysteine protease of Plasmodium falciparum, belongs to calpain-7 family, which is an atypical calpain not harboring Ca2+-binding regulatory motifs. In this present study, in order to establish the screening system for Pf-calpain specific inhibitors, the active form of Pf-calpain was first identified.

Methods

Recombinant Pf-calpain including catalytic subdomain IIa (rPf cal-IIa) was heterologously expressed and purified. Enzymatic activity was determined by both fluorogenic substrate assay and gelatin zymography. Molecular homology modeling was carried out to address the activation mode of Pf-calpain in the aspect of structural moiety.

Results

Based on the measurement of enzymatic activity and protease inhibitor assay, it was found that the active form of Pf-calpain only contains the catalytic subdomain IIa, suggesting that Pf-calpain may function as a monomeric form. The sequence prediction indicates that the catalytic subdomain IIa contains all amino acid residues necessary for catalytic triad (Cys-His-Asn) formation. Molecular modeling suggests that the Pf-calpain subdomain IIa makes an active site, holding the catalytic triad residues in their appropriate orientation for catalysis. The mutation analysis further supports that those amino acid residues are functional and have enzymatic activity.

Conclusion

The identified active form of Pf-calpain could be utilized to establish high-throughput screening system for Pf-calpain inhibitors. Due to its unique monomeric structural property, Pf-calpain could be served as a novel anti-malarial drug target, which has a high specificity for malaria parasite. In addition, the monomeric form of enzyme may contribute to relatively simple synthesis of selective inhibitors.
Superficial and deep lymph node dissection for stage III cutaneous melanoma: clinical outcome and prognostic factors
Authors: Mozzillo Nicola , Caracò Corrado , Marone Ugo , Di Monta Gianluca , Crispo Anna , Botti Gerardo , Montella Maurizio , Ascierto Paolo Antonio
Published: February 2013

Background

The aims of this retrospective analysis were to evaluate the effect of combined superficial and deep groin dissection on disease-free and melanoma-specific survival, and to identify the most important factors for predicting the involvement of deep nodes according to clinically or microscopically detected nodal metastases.

Methods

Between January 1996 and December 2005, 133 consecutive patients with groin lymph node metastases underwent superficial and deep dissection at the National Cancer Institute, Naples. Lymph node involvement was clinically evident in 84 patients and detected by sentinel node biopsy in 49 cases.

Results

The 5-year disease-free survival was significantly better for patients with superficial lymph node metastases than for patients with involvement of both superficial and deep lymph nodes (34.9% vs. 19.0%; P = 0.001). The 5-year melanoma-specific survival was also significantly better for patients with superficial node metastases only (55.6% vs. 33.3%; P = 0.001).

Conclusions

Metastasis in the deep nodes is the strongest predictor of both disease-free and melanoma-specific survival. Deep groin dissection should be considered for all patients with groin clinical nodal involvement, but might be spared in patients with a positive sentinel node. Prospective studies will clarify the issue further.
Numerical simulation of natural convection in a square enclosure filled with nanofluid using the two-phase Lattice Boltzmann method
Authors: Qi Cong , He Yurong , Yan Shengnan , Tian Fenglin , Hu Yanwei
Published: February 2013

Considering interaction forces (gravity and buoyancy force, drag force, interaction potential force, and Brownian force) between nanoparticles and a base fluid, a two-phase Lattice Boltzmann model for natural convection of nanofluid is developed in this work. It is applied to investigate the natural convection in a square enclosure (the left wall is kept at a high constant temperature (T
H), and the top wall is kept at a low constant temperature (T
C)) filled with Al2O3/H2O nanofluid. This model is validated by comparing numerical results with published results, and a satisfactory agreement is shown between them. The effects of different nanoparticle fractions and Rayleigh numbers on natural convection heat transfer of nanofluid are investigated. It is found that the average Nusselt number of the enclosure increases with increasing nanoparticle volume fraction and increases more rapidly at a high Rayleigh number. Also, the effects of forces on nanoparticle volume fraction distribution in the square enclosure are studied in this paper. It is found that the driving force of the temperature difference has the biggest effect on nanoparticle volume fraction distribution. In addition, the effects of interaction forces on flow and heat transfer are investigated. It is found that Brownian force, interaction potential force, and gravity-buoyancy force have positive effects on the enhancement of natural convective heat transfer, while drag force has a negative effect.
Generic diffeomorphisms with weak limit shadowing
Authors: Lu Gang , Lee Keonhee , Lee Manseob
Published: February 2013

In this paper, we show that if a

C
1

-generic diffeomorphism has the weak limit shadowing property on the chain recurrent set, then the diffemorphism satisfies Axiom A and the no-cycle condition.

MSC:37C50, 37D30.
Sclerosing rhabdomyosarcoma presenting in the masseter muscle: a case report
Authors: Lin Xu-Yong , Wang Yan , Yu Juan-Han , Liu Yang , Wang Liang , Li Qing-Chang , Wang En-Hua
Published: February 2013

Sclerosing rhabdomyosarcoma (SRMS) is exceedingly rare, and may cause a great diagnostic confusion. Histologically, it is characterized by abundant extracellular hyalinized matrix mimicking primitive chondroid or osteoid tissue. So, it may be easily misdiagnosed as chondrosarcoma, osteosarcoma, angiosarcoma and so on. Herein, we report a case of SRMS occurring in the masseter muscle in a 40-year-old male. The tumor showed a diverse histological pattern. The tumor cells were arranged into nests, cords, pseudovascular, adenoid, microalveoli and even single-file arrays. Immunostaining showed that the tumor was positive for the Vimentin, Desmin and MyoD1, and was negative for CK, P63, NSE, CD45, CD30, S-100, CD99, Myoglobin, CD68, CD34, CD31, and α–SMA. Based on the morphological finding and immunostaining, it was diagnosed as a SRMS. In addition, focally, our case also displayed a cribriform pattern resembling adenoid cystic carcinoma. This may represent a new histological feature which can broaden the histological spectrum of this tumor and also may lead to diagnostic confusion.

Virtual slides

The virtual slide(s) for this article can be found here:http://www.diagnosticpathology.diagnomx.eu/vs/1615846455818924
Identification of new biomarker candidates for glucocorticoid induced insulin resistance using literature mining
Authors: Fleuren Wilco WM , Toonen Erik JM , Verhoeven Stefan , Frijters Raoul , Hulsen Tim , Rullmann Ton , van Schaik René , de Vlieg Jacob , Alkema Wynand
Published: February 2013

Background

Glucocorticoids are potent anti-inflammatory agents used for the treatment of diseases such as rheumatoid arthritis, asthma, inflammatory bowel disease and psoriasis. Unfortunately, usage is limited because of metabolic side-effects, e.g. insulin resistance, glucose intolerance and diabetes. To gain more insight into the mechanisms behind glucocorticoid induced insulin resistance, it is important to understand which genes play a role in the development of insulin resistance and which genes are affected by glucocorticoids.

Medline abstracts contain many studies about insulin resistance and the molecular effects of glucocorticoids and thus are a good resource to study these effects.

Results

We developed CoPubGene a method to automatically identify gene-disease associations in Medline abstracts. We used this method to create a literature network of genes related to insulin resistance and to evaluate the importance of the genes in this network for glucocorticoid induced metabolic side effects and anti-inflammatory processes.

With this approach we found several genes that already are considered markers of GC induced IR, such asphosphoenolpyruvate carboxykinase(PCK) andglucose-6-phosphatase,catalytic subunit(G6PC). In addition, we found genes involved in steroid synthesis that have not yet been recognized as mediators of GC induced IR.

Conclusions

With this approach we are able to construct a robust informative literature network of insulin resistance related genes that gave new insights to better understand the mechanisms behind GC induced IR. The method has been set up in a generic way so it can be applied to a wide variety of disease networks.
Inability to detect significant absorption of immunoreactive soya protein in healthy adults may be relevant to its weak allergenicity
Authors: Lund Cecilia M , Dirks Christina G , Pedersen Mona H , Jensen Bettina M , Poulsen Lars K
Published: February 2013

Soya and peanut are botanically closely related and share cross‐reacting antigens, but compared to soya, peanut allergy has a higher prevalence with more severe allergic reactions. Furthermore, the threshold dose for eliciting reactions is higher for soya. A difference in undigested protein absorption between the two foods, might explain this diversity.

In the current study the amount of soya protein absorbed after soya bean ingestion in healthy adults was estimated. Ten subjects ingested 100 grams of soya beans (40 grams of soya protein) and blood was drawn before and 1, 3 and 24 hours after administration. Serum was analysed by ELISA and histamine release (HR). In all serum samples the soya protein concentration was below quantification limit (1.6 ng/ml which corresponds to 4.8 μg or 0.12 parts per million absorbed soya protein.

We could not detect any significant absorption of soya protein. While we cannot totally exlude technical reasons, it may also reflect a true poor absorption in healthy adult volunteers. This could, in turn, be relevant to the apparently weak allergenicity of soy protein by comparison with peanut protein in allergic subjects.
Metabolic changes in cancer cells upon suppression of MYC
Authors: Anso Elena , Mullen Andrew R , Felsher Dean W , Matés José M , DeBerardinis Ralph J , Chandel Navdeep S
Published: February 2013

Background

Cancer cells engage in aerobic glycolysis and glutaminolysis to fulfill their biosynthetic and energetic demands in part by activating MYC. Previous reports have characterized metabolic changes in proliferating cells upon MYC loss or gain of function. However, metabolic differences between MYC-dependent cancer cells and their isogenic differentiated counterparts have not been characterized upon MYC suppression in vitro.

Results

Here we report metabolic changes between MYC-dependent mouse osteogenic sarcomas and differentiated osteoid cells induced upon MYC suppression. While osteogenic sarcoma cells increased oxygen consumption and spare respiratory capacity upon MYC suppression, they displayed minimal changes in glucose and glutamine consumption as well as their respective contribution to the citrate pool. However, glutamine significantly induced oxygen consumption in the presence of MYC which was dependent on aminotransferases. Furthermore, inhibition of aminotransferases selectively diminished cell proliferation and survival of osteogenic sarcoma MYC-expressing cells. There were minimal changes in ROS levels and cell death sensitivity to reactive oxygen species (ROS)-inducing agents between osteoid cells and osteogenic sarcoma cells. Nevertheless, the mitochondrial-targeted antioxidant Mito-Vitamin E still diminished proliferation of MYC-dependent osteogenic sarcoma cells.

Conclusion

These data highlight that aminotransferases and mitochondrial ROS might be attractive targets for cancer therapy in MYC-driven tumors.
Effects of early life exposure to ultraviolet C radiation on mitochondrial DNA content, transcription, ATP production, and oxygen consumption in developing Caenorhabditis elegans
Authors: Leung Maxwell CK , Rooney John P , Ryde Ian T , Bernal Autumn J , Bess Amanda S , Crocker Tracey L , Ji Alex Q , Meyer Joel N
Published: February 2013

Background

Mitochondrial DNA (mtDNA) is present in multiple copies per cell and undergoes dramatic amplification during development. The impacts of mtDNA damage incurred early in development are not well understood, especially in the case of types of mtDNA damage that are irreparable, such as ultraviolet C radiation (UVC)-induced photodimers.

Methods

We exposed first larval stage nematodes to UVC using a protocol that results in accumulated mtDNA damage but permits nuclear DNA (nDNA) repair. We then measured the transcriptional response, as well as oxygen consumption, ATP levels, and mtDNA copy number through adulthood.

Results

Although the mtDNA damage persisted to the fourth larval stage, we observed only a relatively minor ~40% decrease in mtDNA copy number. Transcriptomic analysis suggested an inhibition of aerobic metabolism and developmental processes; mRNA levels for mtDNA-encoded genes were reduced ~50% at 3 hours post-treatment, but recovered and, in some cases, were upregulated at 24 and 48 hours post-exposure. The mtDNA polymerase γ was also induced ~8-fold at 48 hours post-exposure. Moreover, ATP levels and oxygen consumption were reduced in response to UVC exposure, with marked reductions of ~50% at the later larval stages.

Conclusions

These results support the hypothesis that early life exposure to mitochondrial genotoxicants could result in mitochondrial dysfunction at later stages of life, thereby highlighting the potential health hazards of time-delayed effects of these genotoxicants in the environment.
Plasma cell disorders in HIV-infected patients: epidemiology and molecular mechanisms
Authors: Coker Woodrow J , Jeter Ashley , Schade Henning , Kang Yubin
Published: February 2013

Highly active antiretroviral therapy (HAART) has significantly improved the outcome and survival of human immunodeficiency virus (HIV)-infected patients. Subsequently, long-term morbidities including cancer have become of major public health and clinical interest for this patient population. Plasma cell disorders occur at higher incidence in HIV-infected patients; however, the molecular mechanisms driving the plasma cell disease process and the optimal management for these patients remain to be defined. This article provides an up-to-date review of the characteristics and management of HIV-infected patients with plasma cell disorders. We first present 3 cases of plasma cell disorders in HIV-infected patients, ranging from polyclonal hypergammaglobulinemia to symptomatic multiple myeloma. We then discuss the epidemiology, clinical presentation, and management of each of these plasma cell disorders, with an emphasis on the molecular events underlying the progression of plasma cell diseases from monoclonal gammopathy to symptomatic multiple myeloma. We propose a three-step hypothesis for the development of multiple myeloma. Finally, we discuss the use of high dose chemotherapy and autologous hematopoietic stem cell transplantation in the treatment of HIV-infected patients with multiple myeloma. Our review includes the care of HIV-infected patients with plasma cell disorders in the current era of HAART and novel agents available for the treatment of multiple myeloma.
Regularized seismic full waveform inversion with prior model information
Authors: Asnaashari Amir , Brossier Romain , Garambois Stéphane , Audebert François , Thore Pierre , Virieux Jean
Published: February 2013

Full waveform inversion (FWI) delivers high-resolution quantitative images and is a promising technique to obtain macroscale physical property model of the subsurface. In most geophysical applications, prior information, such as that collected in wells, is available and should be used to increase the image reliability. For this, we propose to introduce three terms in the definition of the FWI misfit function: the data misfit itself, the first-order Tikhonov regularization term acting as a smoothing operator, and a prior model norm term. This last term is the way to smoothly introduce prior information into the FWI workflow. On a selected target of the Marmousi synthetic example, significant improvement was obtained when using the prior model term for noise-free and noisy synthetic data. The prior model term may significantly reduce the inversion sensitivity to incorrect initial conditions. The limited range of spatial wavenumber sampling by the acquisition may be compensated with the prior model information, for multiple-free and multiple-contaminated data. Prior and initial models play different roles in the inversion scheme. The starting model is used for wave propagation and therefore drives the data-misfit gradient, whereas the prior model is never explicitly used for solving the wave equation and only drives the optimization step as an additional constraint to minimize the total objective function. Thus, the prior model is not required to follow kinematic properties as precisely as the initial model, except in zones of poor illumination. In addition, we investigate the influence of a simple dynamic decreasing weighting of the prior model term. Once the cycle-skipping problem has been solved, the impact of the prior model term is gradually reduced within the misfit function to be driven by seismic-data only.
Competitive Export Pricing: The Influence of the Information Context
Authors: Obadia Claude
Published: February 2013

This study investigates how the information context of cross-border exchanges influences the implementation and effectiveness of export pricing policies. Using a disaggregate approach to measure export pricing, the research shows the influence of the competitive intensity and the ambiguity of the foreign market on each facet of the pricing policy. In addition, this research investigates the effectiveness of these price manipulations in a context of information asymmetry. The findings suggest that exporters manipulate prices when confronted with competitive and ambiguous foreign markets. However, in most cases, these price manipulations have no impact on performance. Furthermore, when information asymmetry is high, export price manipulations deteriorate performance. The analysis uses survey data from 278 French exporters.
The Impact of Brand Rating Dispersion on Firm Value
Authors: Luo Xueming , Raithel Sascha , Wiles Michael A.
Published: February 2013

This study examines brand dispersion—variance in brand ratings across consumers—and its role in the translation of brand assets into firm value. Dispersion captures the covert heterogeneity in brand evaluations among consumers who like or dislike the brands, which would affect an investor's decision to buy or sell a stock. The higher the dispersion, the more inconsistent and polarized the brands’ cross-consumer ratings. Multiple analyses on 730,818 brand–day observations provide robust evidence that brand dispersion fluctuations affect stock prices. Brand dispersion has Januslike effects: it harms returns but reduces firm risk. Furthermore, downside dispersion has a stronger impact on abnormal returns than upside dispersion, indicating an asymmetry in brand dispersion's effects. Moreover, dispersion tempers the risk-reduction benefits of higher brand rating in both the short run and long run. Without modeling dispersion, brand rating's impact on firm value can be over- or underestimated. Managers should consider dispersion a vital brand-management metric and add it to the brand-performance dashboard.
Optical design with orthogonal representations of rotationally symmetric and freeform aspheres
Authors: Menke Christoph , Forbes G.W.
Published: February 2013

We review the motivations and intended benefits of orthogonalized representations of aspheric shapes and demonstrate unexpected gains for design purposes. Leaving aside improvements in ‘design for manufacturability’, we show that local optimization within standard design codes can find solutions with better optical performance when orthogonal descriptions are employed. Our examples include rotationally symmetric systems as well as systems with no global axis of symmetry and even a system of freeform surfaces (i.e., with no individual axes of symmetry).
The astigmatic aberration field in active primary mirror astronomical telescopes
Authors: Thompson Kevin P.
Published: February 2013

Stemming from the exceptional results obtained with the pathfinding NTT telescope commissioned in 1989, the current generation of large astronomical telescopes, including the VLT, Gemini, Subaru, LBT, VST, and many more, use an active primary mirror in conjunction with the position of the secondary mirror to optimize performance with a cycle time typically measured in minutes over the course of acquiring a long exposure image. Recent discoveries, based in research enabled by the nodal aberration theory (NAT), have created a complete, linear model for the effect of, and the interaction of, the alignment compensators used during an exposure when an active primary mirror has a role in the process of maintaining performance in combination with the rotation of the secondary mirror around a specific external pivot point. This scenario, presented in the context of NAT, clearly illustrates important, limiting interactions between the secondary mirror position and the primary mirror astigmatic figure residual created through active control. It also points to the need for the wavefront sensor algorithm to anticipate that the astigmatic field will be binodal. The science of weak galactic lensing is exceptionally sensitive to binodal astigmatism, making this aberration field an urgent area of research.
Handheld Mobile Device Based Text Region Extraction and Binarization of Image Embedded Text Documents
Authors: Mollah Ayatullah Faruk , Basu Subhadip , Nasipuri Mita , Basu Dipak Kumar
Published: February 2013

Effective text region extraction and binarization of
image embedded text documents on mobile devices having limited computational
resources is an open research problem. In this paper, we present one
such technique for preprocessing images captured with built-in cameras of
handheld devices with an aim of developing an efficient Business Card Reader.
At first, the card image is processed for isolating foreground
components. These foreground components are classified as either text or
non-text using different feature descriptors of texts and images. The
non-text components are removed and the textual ones are binarized with a
fast adaptive algorithm. Specifically, we propose new techniques
(targeted to mobile devices) for (i) foreground component isolation, (ii)
text extraction and (iii) binarization of text regions from camera captured
business card images. Experiments with business card images of various
resolutions show that the present technique yields better accuracy and
involves low computational overhead in comparison with the state-of-the-art.
We achieve optimum text/non-text separation performance with images of
resolution 800×600 pixels with an average recall rate of 93.90% and
a precision rate of 96.84%. It involves a peak memory
consumption of 0.68 MB and processing time of 0.102 seconds on a moderately
powerful notebook, and 4 seconds of processing time on a PDA.
Two dimensional cyano-bridged heteropolynuclear complex containing Pd ···π interactions
Authors: Karaağaç Dursun , Kürkçüoğlu Güneş Süheyla , Hökelek Tuncer , Yeşilel Okan Zafer , Süzen Yasemin
Published: February 2013

The heteronuclear complex, [Cd(NH3)2(μ-ampy)Pd(μ-CN)2(CN)2]
n
(1) (ampy = 4-aminomethylpyridine), was synthesized and characterized by vibrational (FT-IR and Raman) spectroscopy, elemental and thermal analyses and single crystal X-ray diffraction techniques. The complex crystallizes in the triclinic system, space group P-1. The Cd(II) ion exhibits a distorted octahedral coordination by two different N-atoms from two symmetrically equivalent ampy ligands, two ammine ligands and two bridging cyano groups, whereas the Pd(II) ion has square planar coordination and is coordinated by four cyano ligands. The tetracyanopalladate(II) anion is coordinated to the adjacent two Cd(II) ions to generate a one-dimensional chain. The adjacent 1D chains are connected by the μ-ampy bridging ligands to form a 2D network. The 2D layers are further linked by Pd···π and hydrogen bonding interactions to generate a 3D supramolecular network. The decomposition reaction takes places in the temperature range of 40–900 °C in the static air atmosphere.
Device therapy of resistant hypertension
Authors: Simonyi Gábor , Bedros J. Róbert , Medvegy Mihály
Published: February 2013

It is well known that hypertension is an independent cardiovascular risk factor. Treatment of hypertension frequently includes administration of three or more drugs. Resistant hypertension is defined when blood pressure remains above target value despite full doses (the patient’s maximum tolerated dose) of antihypertensive medication consisting of at least three different classes of drugs including a diuretic. Pharmacological treatment of hypertension is often unsuccessful despite the increasing number of drug combinations. Uncontrolled hypertension, however, increases the cardiovascular risk. Device treatment of resistant hypertension is currently testing two major fields. One of them the stimulation of baroreceptors in the carotid sinus and the other is radiofrequency ablation of sympathetic nerve fibers around renal arteries to reduce blood pressure in drug resistant hypertension. Orv. Hetil., 2013, 154, 203–208.
Laser induced patterning of Bi thin films
Authors: Zepeda Carlos Acosta , Mecalco Giovanni , Hernández-Pozos J. L. , Zepeda Marco Antonio , Batina N. , Haro-Poniatowski E.
Published: February 2013

Laser irradiation of Bismuth thin films through a diffractive mask was investigated. The thin films were composed of nano and microcrystals Bismuth with sizes ranging from 20 to 500 nm. Upon laser irradiation (λ=355 nm) the structured illumination field locally modified the material. In the high intensity regions the surface was transformed whilst low intensity areas were left intact. The modification mechanism was melting followed by coalescence of the nanocrystals giving rise to a more uniform structure. The laser irradiated area was characterized by scanning electron microscopy and atomic force microscopy. The patterns were computed by Fresnel diffraction theory and the agreement between the theory and the experiments was very good.
Why all those spines? Anachronistic defences in the Didiereoideae against now extinct lemurs
Authors: Crowley Brooke E. , Godfrey Laurie R.
Published: February 2013

Plants evolve physical defences, such as spines, against browsing herbivores. However, in some cases, these defences may be anachronistic because the principal consumers of protected parts of the plant are extinct. In such cases, there may be few extant species consuming heavily defended resources. Here we examine the spiny defences of Madagascar’s endemic Didiereoideae, and ask whether they may be anachronistic. To accomplish this aim, we reviewed the literature to determine which species consume these plants today, and then used stable isotope biogeochemistry to determine who may have exploited Didiereoideae in the recent past. There are four major groups of browsers that are now extinct in Madagascar: giant lemurs, elephant birds (Aepyornis and Mullerornis: Aepyornithidae), pygmy hippopotamuses (Hippopotamus) and giant tortoises (Aldabrachelys: Testudinidae). Each group was evaluated for isotopic evidence of didiereoid plant consumption. Given the structure of members of this plant clade (especially Alluaudia), we predicted that lemurs would be their most important consumers. Three extant lemur species consume Didiereoideae. Several of the extinct lemurs, particularly Hadropithecus stenognathus, may have relied heavily on these spiny plants. None of the non-lemur megafaunal browsers (elephant birds, hippopotamuses and giant tortoises) were important consumers of Didiereoideae.