bluuebunny/crossref_metadata_2025 huggingface dataset:
Hypoxia Selectively Disrupts Brain Microvascular Endothelial Tight Junction Complexes Through a Hypoxia‐Inducible Factor‐1 (HIF‐1) Dependent Mechanism
Authors: Engelhardt Sabrina , Al‐Ahmad Abraham J. , Gassmann Max , Ogunshola Omolara O.
Published: December 2013

The blood–brain barrier (BBB) constitutes a critical barrier for the maintenance of central nervous system homeostasis. Brain microvascular endothelial cells line the vessel walls and express tight junction (TJ) complexes that restrict paracellular passage across the BBB, thereby fulfilling a crucial role in ensuring brain function. Hypoxia, an impaired O2 delivery, is known to cause BBB dysfunction but the mechanisms that drive this disruption remain unclear. This study discloses the relevance of the master regulator of the hypoxic response, hypoxia‐inducible factor‐1 (HIF‐1), in hypoxia‐induced barrier disruption using the rat brain endothelial cell line RBE4. Hypoxic exposure rapidly induced stabilization of the HIF‐1 oxygen‐dependent alpha subunit (HIF‐1α) concomitantly with BBB impairment and TJ disruption mainly through delocalization and increased tyrosine phosphorylation of TJ proteins. Similar observations were obtained by normoxic stabilization of HIF‐1α using CoCl2, deferoxamine, and dimethyloxalylglycine underlining the involvement of HIF‐1 in barrier dysfunction particularly via TJ alterations. In agreement inhibition of HIF‐1 stabilization by 2‐methoxyestradiol and YC‐1 improved barrier function in hypoxic cells. Overall our data suggests that activation of HIF‐1‐mediated signaling disrupts TJ resulting in increased BBB permeability. J. Cell. Physiol. 229: 1096–1105, 2014. © 2013 Wiley Periodicals, Inc.
Stability analysis of uncertain switched singular time‐delay systems with discrete and distributed delays
Authors: Zamani Iman , Shafiee Masoud
Published: December 2013

The issues of stability analysis of a class of continuous uncertain switched singular time‐delay systems consisting of discrete and distributed delays is investigated in this paper. Based on the LMIs, constructing the new extended Lyapunov‐like Krasovskii functional, and the average dwell‐time approach, delay‐dependent sufficient conditions are derived to check the stability of such systems. By solving the corresponding LMIs, the average dwell‐time and switching signal condition are obtained. This paper also highlights the relationship between the average dwell‐time of the switched singular time‐delay system, exponential rate of differential, and algebraic states. Two numerical examples show the effectiveness of the proposed design method. Copyright © 2013 John Wiley & Sons, Ltd.
Development of resin transfer molding process using scaling down strategy
Authors: Kuppusamy Raghu Raja Pandiyan , Neogi Swati
Published: December 2013

The virtually developed resin transfer molding (RTM) manufacturing process for the large and complex composite part can be validated easily with the trial experiments on the scaled down mold. The scaling down strategy was developed using Darcy's law from the comparisons of mold fill time and mold fill pattern between full‐scale product and scaled down prototype. From the analysis, it was found that the injection pressure used in the scaled down mold should be the full‐scale injection pressure by the times of square of geometrical scale down factor, provided the identical injection strategy and raw material parameters were applied on both the scales. In this work, the RTM process was developed using process simulations for a large and complex high‐speed train cab front and it was validated by conducting experiments using a geometrically scaled down mold. The injection pressure as per the scaling down strategy was imposed on the scale downed high‐speed train cab front mold and a very close agreement was observed between the flow fronts of experimental and simulated results, which validates the scaling down strategy and the virtually developed RTM process for the full‐scale product. POLYM. COMPOS., 35:1683–1689, 2014. © 2013 Society of Plastics Engineers
Solid‐state foaming of carbon fiber/polypropylene/nano‐CACO3 composite using supercritical CO2
Authors: Wang Chuanbao , Ying Sanjiu
Published: December 2013

In this work, nano‐CaCO3 was used to improve the foamability of carbon fiber (CF)/polypropylene (PP) composite in solid‐state foaming using supercritical CO2. The CF content was maintained at 15 wt% and four concentrations of nano‐CaCO3 content, 1, 3, 5 and 8phr, were used. The surface of nano‐CaCO3 was firstly treated by silane coupling agent. By the way, the properties of the nano‐composites with various nano‐CaCO3 contents were analyzed by scanning electron microscope (SEM), differential scanning calorimeter (DSC), and torque rheometer. Before foaming, the gas absorption experiment was done using gravimetric method. Concerning on determination of the foaming conditions, it is found that 175°C and 60s were suitable as foaming temperature and time. Furthermore, we can also find that the foamed composites with 3phr nano‐CaCO3 showed the smallest mean cell diameter and largest cell density compared with the other nano‐CaCO3 contents under the given saturation condition. In addition, the mean cell diameter decreased while cell density increased as saturation pressure increased because of the higher gas solubility in the composites. When the saturation pressure was 25MPa, the mean cell diameter and cell density with 3phr nano‐CaCO3 were 17μm and 2.20×107cells/cm3, respectively. POLYM. COMPOS., 35:1723–1735, 2014. © 2013 Society of Plastics Engineers
Investigation of mechanical properties, antibacterial features, and water vapor permeability of polyvinyl alcohol thin films reinforced by glutaraldehyde and multiwalled carbon nanotube
Authors: Mohammad Mahdi Dadfar Seyed , Kavoosi Gholamreza , Mohammad Ali Dadfar Seyed
Published: December 2013

Polyvinyl alcohol (PVA) thin films were reinforced by glutaraldehyde and multiwalled carbon nanotubes (MWCNTs) and then mechanical, water solubility, water swelling, water uptake, water vapor permeability, and antibacterial properties of the films were examined. Cross‐linking by glutaraldehyde or incorporation of MWCNT caused a significant increase in tensile strength, decrease in elongation at break, and increase in Young's modulus of the PVA films, while MWCNTs were more effective rather than that of glutaraldehyde. Cross‐linking by glutaraldehyde or incorporation of MWCNT caused a significant decrease in water solubility, water swelling and water uptake, with a similar manner. Cross‐linking by glutaraldehyde or incorporation of MWCNT caused a significant increase in the light absorbance, while maximum absorbance was at 400 nm. Only PVA/MWCNT films but no PVA/glutaraldehyde showed significant antibacterial activities in a dose‐dependent manner against both Gram‐positive and Gram‐negative bacteria. Thus, noncovalent improvement by MWCNT was more effective on the PVA thin films rather than covalent cross‐linking by glutaraldehyde. Our results suggest that the PVA/MWCNT composites films could be used as a very attractive alternative to traditional materials for different biomedical and food applications. POLYM. COMPOS., 35:1736–1743, 2014. © 2013 Society of Plastics Engineers
When much more of a difference makes a difference: Social comparison and tournaments in the CEO's top team
Authors: Ridge Jason W. , Aime Federico , White Margaret A.
Published: December 2013

We integrate the seemingly contradictory theoretical predictions of behavioral and economic perspectives about the relationship between pay disparity and firm performance and show that tournament and social comparison theories are more supplementary than contradictory in nature. Our results show that high levels of firm performance will be found around either meaningfully low or meaningfully high levels of pay disparity. Additional findings indicate that this curvilinear relationship is weakened in the presence of both an heir apparent and high CEO power, and strengthened when top management team members are more eligible as CEOs. These findings suggest that factors that increase or inhibit social comparison or tournament perceptions among TMT members play a role in the strength of the curvilinear relationship between pay disparity and firm performance. Copyright © 2013 John Wiley & Sons, Ltd.
Prevalence of extrauterine pelvic lesions on transvaginal ultrasound in asymptomatic 20–39‐year‐old women
Authors: Jokubkiene L. , Sladkevicius P. , Valentin L.
Published: December 2013

Objectives

To estimate the prevalence of extrauterine pelvic lesions on transvaginal ultrasound examination of gynecologically asymptomatic women of fertile age, and to compare this prevalence between women with spontaneous menstrual cycles, those using the combined oral contraceptive (COC) pill and those using a gestagen intrauterine contraceptive device (IUD).

Methods

Six hundred and forty‐four gynecologically asymptomatic 20–39‐year‐old Caucasian women with no current or previous gynecological problems, who were recruited from a Swedish population registry, were examined with transvaginal ultrasound on cycle day 4–8. Our definition of ovarian cyst was a unilocular cyst with anechoic cyst contents ≥ 35 mm in mean diameter, or any other type of intraovarian lesion. The prevalence of extrauterine pelvic lesions was compared between women not using hormonal contraception and those using COC or a gestagen IUD.

Results

Ovarian lesions were found in 24 (3.7%) women. One woman had bilateral ovarian lesions. An ultrasound diagnosis of paraovarian cyst was made in 41 (6.4%) women, of peritoneal cyst in four (0.6%) women and of hydrosalpinx in one (0.2%) woman. All incidentally detected lesions had a mean diameter of ≤ 5 cm. One 17‐mm intraovarian lesion was suspicious for malignancy, and histology confirmed a Sertoli–Leydig cell tumor. The ultrasound diagnoses in the remaining 23 women were endometrioma (n = 10 (1.6%)), dermoid cyst (n = 5 (0.8%)), cystadenofibroma (n = 1 (0.2%)), mature teratoma (n = 1 (0.2%)) and functional cyst, i.e. a cyst that resolved within 3–5 months (n = 6 (0.9%)). Four women with an ultrasound diagnosis of a benign lesion were operated on, and the ultrasound diagnoses of endometrioma (n = 2), dermoid cyst (n = 1) and mature teratoma (n = 1) were confirmed histologically. The prevalence of persisting ovarian lesions was highest in women with spontaneous menstrual cycles (4.4% vs 0.9% and 0% in women using COC and gestagen IUD, respectively; P = 0.025), but age was the only factor independently associated with persisting ovarian masses, the prevalence increasing with age.

Conclusions

Benign ovarian lesions are found in about 1 in 25 gynecologically asymptomatic women aged 20–39 years with no history of gynecological disease. To be able to offer optimal management of such masses, their natural history needs to be elucidated in a large prospective observational study. Copyright © 2013 ISUOG. Published by John Wiley & Sons Ltd
Schizosaccharomyces japonicus: the fission yeast is a fusion of yeast and hyphae
Authors: Niki Hironori
Published: December 2013

The clade of Schizosaccharomyces includes 4 species: S. pombe, S. octosporus, S. cryophilus, and S. japonicus. Although all 4 species exhibit unicellular growth with a binary fission mode of cell division, S. japonicus alone is dimorphic yeast, which can transit from unicellular yeast to long filamentous hyphae. Recently it was found that the hyphal cells response to light and then synchronously activate cytokinesis of hyphae. In addition to hyphal growth, S. japonicas has many properties that aren't shared with other fission yeast. Mitosis of S. japonicas is referred to as semi‐open mitosis because dynamics of nuclear membrane is an intermediate mode between open mitosis and closed mitosis. Novel genetic tools and the whole genomic sequencing of S. japonicas now provide us with an opportunity for revealing unique characters of the dimorphic yeast. © 2013 The Author. Yeast Published by John Wiley & Sons Ltd.
R1 Hepatectomy With Exposure of Tumor Surface for Centrally Located Hepatocellular Carcinoma
Authors: Yu Weibo , Rong Weiqi , Wang Liming , Wu Fan , Xu Quan , Wu Jianxiong
Published: December 2013

Background

Hepatectomy with exposure of tumor surface (a special type of R1 resection) provides a chance of cure for selected patients with centrally located hepatocellular carcinoma (HCC) that is adherent to or compresses major vessels. However, the operative indications, safety, and patient outcomes are not well defined.

Methods

We performed hepatectomy for removal of complex centrally located HCC using a selective and dynamic region‐specific vascular occlusion technique. Between May 2006 and March 2012, a total of 118 patients underwent resection with exposure of tumor surface (exposure group) and 169 underwent conventional hepatectomy (without exposure of the tumor and vascular surface). The short‐ and long‐term outcomes of patients were evaluated and compared.

Results

The postoperative recovery of liver function was comparable between the two groups. Bile leakage occurred in five patients, all in the exposure group. The 1‐, 3‐, and 5‐year recurrence‐free survival rates were 74.4, 45.6, and 30.1 % in the exposure group and 80.9, 57.2, and 31.7 % in the control group (p = 0.041). Corresponding overall survival rates were 92.3, 70.3, and 44.9 % in the exposure group and 97.8, 81.4, and 53.1 % in the control group (p = 0.094).

Conclusions

Hepatectomy with exposure of tumor surface is technically demanding, but can be performed safely. It is also associated with a risk of tumor recurrence. Multidisciplinary combined therapy would be the solution and can contribute to improve overall survival.
Optimization of Lipase‐Catalyzed Fractionation of Two Conjugated Linoleic Acid (CLA) Isomers
Authors: Jafari Maryam , Kadivar Mahdi , Goli Sayed Amir Hossein , Ghiaci Mehran
Published: December 2013

The separation of two isomers of conjugated linoleic acid is highly significant since each exhibits different biochemical properties. The aim of this study was to investigate and optimize several factors affecting the esterification of l‐menthol with the c9,t11‐CLA isomer in an organic solvent‐free system using lipase from Candida rugosa (Lipase AY‐30). D‐optimal design with 5 factors and 3 levels were employed to evaluate the effects of synthesis parameters; reaction time (8–24 h), temperature (30–50 °C), enzyme content (2–20 U/ml), substrate molar ratio of conjugated linoleic acid oil to l‐menthol (2:1–1:2) and pH (6–8) on esterification of c9,t11‐CLA with l‐menthol. Based on the analysis of the residual amount of c9,t11‐CLA in the free fatty acid fraction after just one‐step esterification, the optimum synthesis conditions were as follows: reaction time 23.12 h, temperature 32.65 °C, enzyme amount 135.40 U, molar ratio of CLA oil to l‐menthol at 1:1.7 and pH at 7.7; the lowest purity of c9,t11‐CLA in free fatty acid fraction based on the total content of c9,t11 and t10,c12‐CLA isomers was 8.6 %.
Associations among sleep, daily experiences, and loneliness in adolescence: Evidence of moderating and bidirectional pathways
Authors: Doane Leah D. , Thurston Emily C.
Published: December 2013

The present study examined the dynamic associations among daily stress levels, affect, and objective sleep quality in adolescence. We also explored loneliness as a potential moderator of these associations. Seventy‐eight adolescents participated over three days. They completed diary reports of stressful experiences and affect five times a day while wearing an actigraph to obtain objective measurement of sleep. They also provided self‐reports of loneliness. High daily stress was associated with shorter sleep duration. Models testing bidirectional associations indicated that prior day stress was associated with shorter sleep duration, but poor sleep duration and sleep efficiency were also associated with greater stress the next day. Loneliness was a significant moderator of the associations between daily stress and sleep duration and latency such that lonely individuals had shorter sleep durations and sleep latencies after particularly stressful days. Results suggest daily dynamic associations among loneliness, daily stress, and objective measures of adolescent sleep.
Pubertal timing and vulnerabilities to depression in early adolescence: Differential pathways to depressive symptoms by sex☆
Authors: Hamilton Jessica L. , Hamlat Elissa J. , Stange Jonathan P. , Abramson Lyn Y. , Alloy Lauren B.
Published: December 2013

Although research implicates pubertal processes in the emergence of the sex difference in depression during adolescence, few studies have examined how cognitive and affective vulnerabilities influence the effect of pubertal timing on depressive symptoms. The current study prospectively examined whether early pubertal timing predicted increases in depressive symptoms among adolescents with more negative cognitive styles and lower emotional clarity, and whether this risk was specific to adolescent girls. In a diverse sample of 318 adolescents, early pubertal timing predicted increases in depressive symptoms among adolescent boys and girls with more negative cognitive styles and adolescent girls with poor emotional clarity. These findings suggest that earlier pubertal maturation may heighten the risk of depression for adolescents with pre‐existing vulnerabilities to depression, and that early maturing adolescent girls with lower levels of emotional clarity may be particularly vulnerable to depressive symptoms, representing one pathway through which the sex difference in depression may emerge.
Trust and social reciprocity in adolescence – A matter of perspective‐taking
Authors: Fett Anne‐Kathrin J. , Shergill Sukhi S. , Gromann Paula M. , Dumontheil Iroise , Blakemore Sarah‐Jayne , Yakub Farah , Krabbendam Lydia
Published: December 2013

Changes in social behaviour from childhood to adulthood have been suggested to be driven by an increased sensitivity to others' perspectives. Yet, the link between perspective‐taking and social processes, such as trust and reciprocity, has rarely been investigated during adolescence. Using two trust games with a cooperative and an unfair counterpart and an online perspective‐taking task with 50 adolescents, we show that those with a higher perspective‐taking tendency demonstrate greater trust towards others and higher levels of trust during cooperative interactions. Both low and high perspective‐takers adapted their levels of trust in response to unfair behaviour. However, high perspective‐takers reduced their trust more drastically and showed more malevolent and less benevolent tit‐for‐tat when they were treated unfairly by their counterpart. The findings suggest that a higher perspective‐taking tendency in adolescence is associated with specific mechanisms of trust and reciprocity, as opposed to undifferentiated increases in positive social behaviour towards others.
Parallel evolution of IDH2 gene in cetaceans, primates and bats
Authors: Ai Wei-Ming , Chen Shao-Bo , Chen Xiao , Shen Xue-Juan , Shen Yong-Yi
Published: December 2013

Cetaceans and primates both have large brains that require large amounts of aerobic energy metabolism. In bats, the cost of flight makes locomotion energetically demanding. These mammalian groups may represent three independent evolutionary origins of an energy‐demanding lifestyle in mammals. IDH2 encodes an enzyme in the tricarboxylic acid cycle in the mitochondrion, which plays a key role in aerobic energy metabolism. In this study, we cloned and sequenced this gene in two cetaceans, and 19 bat species, and compared the data with available primate sequences to test its evolution. We found significant signals of parallel evolution in this gene among these three groups. Parallel evolution of this gene may reflect their parallel evolution towards a higher demand for energy.
Cell and tissue‐autonomous development of the circadian clock in mouse embryos
Authors: Inada Yutaka , Uchida Hitoshi , Umemura Yasuhiro , Nakamura Wataru , Sakai Takayoshi , Koike Nobuya , Yagita Kazuhiro
Published: December 2013

The emergence of the circadian rhythm is a dramatic and physiologically essential event for mammals to adapt to daily environmental cycles. It has been demonstrated that circadian rhythms develop during the embryonic stage even when the maternal central pacemaker suprachiasmatic nucleus has been disrupted. However, the mechanisms controlling development of the circadian clock are not yet fully understood. Here, we show that the circadian molecular oscillation in primary dispersed embryonic cells and explanted salivary glands obtained from mPER2Luc
mice embryos developed cell‐ or tissue‐autonomously even in tissue culture conditions. Moreover, the circadian clock in the primary mPER2Lu

c fibroblasts could be reprogrammed by the expression of the reprogramming factors. These findings suggest that mammalian circadian clock development may interact with cellular differentiation mechanisms.
Upregulation of MicroRNA‐107 induces proliferation in human gastric cancer cells by targeting the transcription factor FOXO1
Authors: Li Fan , Liu Baohua , Gao Yu , Liu Yuliang , Xu Yu , Tong Weidong , Zhang Anping
Published: December 2013

MicroRNA‐107 (miR‐107) has been demonstrated to regulate proliferation and apoptosis in many types of cancers. Nevertheless, its biological function in gastric cancer remains largely unexplored. Here, we found that the expression level of miR‐107 was increased in gastric cancer in comparison with the adjacent normal tissues. The enforced expression of miR‐107 was able to promote cell proliferation in NCI‐N87 and AGS cells, while miR‐107 antisense oligonucleotides (antisense miR‐107) blocked cell proliferation. At the molecular level, our results further revealed that expression of FOXO1 was negatively regulated by miR‐107. Therefore, the data reported here demonstrate that miR‐107 is an important regulator in gastric cancer, which will contribute to a better understanding of the important mis‐regulated miRNAs in gastric cancer.
The N‐terminus of α‐synuclein is essential for both monomeric and oligomeric interactions with membranes
Authors: Lorenzen Nikolai , Lemminger Lasse , Pedersen Jannik Nedergaard , Nielsen Søren Bang , Otzen Daniel Erik
Published: December 2013

The intrinsically disordered protein α‐synuclein (αSN) is linked to Parkinson's Disease and forms both oligomeric species and amyloid fibrils. The N‐terminal part of monomeric αSN interacts strongly with membranes and αSN cytotoxicity has been attributed to oligomers’ ability to interact with and perturb membranes. We show that membrane folding of monomeric wt αSN and N‐terminally truncated variants correlates with membrane permeabilization. Further, the first 11 N‐terminal residues are crucial for monomers’ and oligomers’ interactions with and permeabilization of membranes. We attribute oligomer permeabilization both to cooperative electrostatic interactions through the N‐terminus and interactions mediated by hydrophobic regions in the oligomer.
The succinate dehydrogenase assembly factor, SdhE, is required for the flavinylation and activation of fumarate reductase in bacteria
Authors: McNeil Matthew B. , Hampton Hannah G. , Hards Kiel J. , Watson Bridget N.J. , Cook Gregory M. , Fineran Peter C.
Published: December 2013

The activity of the respiratory enzyme fumarate reductase (FRD) is dependent on the covalent attachment of the redox cofactor flavin adenine dinucleotide (FAD). We demonstrate that the FAD assembly factor SdhE, which flavinylates and activates the respiratory enzyme succinate dehydrogenase (SDH), is also required for the complete activation and flavinylation of FRD. SdhE interacted with, and flavinylated, the flavoprotein subunit FrdA, whilst mutations in a conserved RGxxE motif impaired the complete flavinylation and activation of FRD. These results are of widespread relevance because SDH and FRD play an important role in cellular energetics and are required for virulence in many important bacterial pathogens.
Preeclampsia alters milk neurotrophins and long chain polyunsaturated fatty acids
Authors: Dangat Kamini , Kilari Anitha , Mehendale Savita , Lalwani Sanjay , Joshi Sadhana
Published: December 2013

Objective

To examine the levels of breast milk neurotrophins 1.5, 3.5, and 6 months of lactation and long chain polyunsaturated fatty acids (LCPUFA) at day 3, 1.5, 2.5, 3.5 and 6 months of lactation in mothers with preeclampsia and compare them with normotensive women. Their associations with growth parameters in children are also examined.

Methods

Women with preeclampsia (n = 101) and normotensive women (n = 144) with singleton pregnancies were recruited for this study. Milk samples were collected and anthropometry was recorded at the first 6 months. The LCPUFA composition of milk samples was analyzed by using gas chromatography at all time points and neurotrophins were analyzed at 1.5, 3.5 and 6 months by Emax Immuno Assay System using Promega kits.

Results

Milk DHA levels were higher at day 3 (9.5%), and 1.5 (23%) and 3.5 (40%) months in mothers with preeclampsia as compared to controls. Milk nerve growth factor (NGF) levels were lower in preeclampsia group as compared to control group at 1.5 (20%) and 3.5 months (27.7%). Milk brain derived neurotrophic factor (BDNF) levels were lower at 1.5 months (10.5%) in the preeclampsia group as compared to control group.

Conclusion

The present study suggests that there is a differential regulation of DHA and neurotrophins in breast milk in preeclampsia and are associated with growth parameters of children. Future studies should explore the associations between milk LCPUFA, neurotrophins with neurodevelopment in children.
Spreading depression features and Iba1 immunoreactivity in the cerebral cortex of developing rats submitted to treadmill exercise after treatment with monosodium glutamate
Authors: Lima Cássia Borges , Soares Georgia de Sousa Ferreira , Vitor Suênia Marcele , Andrade‐da‐Costa Belmira Lara da Silveira , Castellano Bernardo , Guedes Rubem Carlos Araujo
Published: December 2013

Physical exercise and excessive consumption of monosodium glutamate (MSG) can affect the morphological and electrophysiological organization of the brain during development. However, the interaction of both factors remains unclear. We analyzed the effect of this interaction on the excitability‐related phenomenon known as cortical spreading depression (CSD) and the microglial reaction expressed as Iba1‐immunolabeled cells in the rat motor cortex. MSG (2 g/kg or 4 g/kg) was administered every other day during the first 14 postnatal days. Treadmill exercise started at 21–23 days of life and lasted 3 weeks, 5 days/week, for 30 min/day. At 45–60 days, CSD was recorded for 4 h at two cortical points and the CSD parameters (velocity, amplitude, and duration of the negative potential change) calculated. Confirming previous observations, exercised rats presented with lower CSD velocities (3.29 ± 0.18 mm/min) than the sedentary group (3.80 ± 0.18 mm/min; P < 0.05). MSG increased CSD velocities in the exercised rats compared to saline‐treated and exercised animals in a dose‐dependent manner (3.49 ± 0.19, 4.05 ± 0.18, and 3.27 ± 0.26 for 2 g/kg MSG, 4 g/kg MSG, and saline, respectively; P < 0.05). The amplitude (ranging from 14.3 ± 5.9 to 18.7 ± 6.2 mV) and duration (46.7 ± 11.1 to 60.5 ± 11.6 s) of the negative slow potential shift of the CSD were similar in all groups. Both exercise and MSG treatment increased Iba1 immunolabeling. The results confirm that physical exercise decelerates CSD propagation. However, it does not impede the CSD‐accelerating action of MSG. These effects were accompanied by a cortical microglia reaction. Therefore, the data suggest that treadmill exercise early in life can influence the development of cortical electrical activity.
LIM‐homeobox gene 2 promotes tumor growth and metastasis by inducing autocrine and paracrine PDGF‐B signaling
Authors: Kuzmanov Aleksandar , Hopfer Ulrike , Marti Patricia , Meyer-Schaller Nathalie , Yilmaz Mahmut , Christofori Gerhard
Published: December 2013

An epithelial‐mesenchymal transition (EMT) is a critical process during embryonic development and the progression of epithelial tumors to metastatic cancers. Gene expression profiling has uncovered the transcription factor LIM homeobox gene 2 (Lhx2) with up‐regulated expression during TGFβ‐induced EMT in normal and cancerous breast epithelial cells. Loss and gain of function experiments in transgenic mouse models of breast cancer and of insulinoma in vivo and in breast cancer cells in vitro indicate that Lhx2 plays a critical role in primary tumor growth and metastasis. Notably, the transgenic expression of Lhx2 during breast carcinogenesis promotes vessel maturation, primary tumor growth, tumor cell intravasation and metastasis by directly inducing the expression of platelet‐derived growth factor (PDGF)‐B in tumor cells and by indirectly increasing the expression of PDGF receptor‐β (PDGFRβ) on tumor cells and pericytes. Pharmacological inhibition of PDGF‐B/PDGFRβ signaling reduces vessel functionality and tumor growth and Lhx2‐induced cell migration and cell invasion. The data indicate a dual role of Lhx2 during EMT and tumor progression: by inducing the expression of PDGF‐B, Lhx2 provokes an autocrine PDGF‐B/PDGFRβ loop required for cell migration, invasion and metastatic dissemination and paracrine PDGF‐B/PDGFRβ signaling to support blood vessel functionality and, thus, primary tumor growth.
Higher-order electric multipole contributions to retarded non-additive three-body dispersion interaction energies between atoms: Equilateral triangle and collinear configurations
Authors: Salam A.
Published: December 2013

The theory of molecular quantum electrodynamics (QED) is used to calculate higher electric multipole contributions to the dispersion energy shift between three atoms or molecules arranged in a straight line or in an equilateral triangle configuration. As in two-body potentials, three-body dispersion interactions are viewed in the QED formalism to arise from exchange of virtual photons between coupled pairs of particles. By employing an interaction Hamiltonian that is quadratic in the electric displacement field means that third-order perturbation theory can be used to yield the energy shift for a particular combination of electric multipole polarizable species, with only six time-ordered diagrams needing to be summed over. Specific potentials evaluated include dipole-dipole-quadrupole (DDQ), dipole-quadrupole-quadrupole (DQQ), and dipole-dipole-octupole (DDO) terms. For the geometries of interest, near-zone limiting forms are found to exhibit an R−11 dependence on separation distance for the DDQ interaction, and an R−13 behaviour for DQQ and DDO shifts, agreeing with an earlier semi-classical computation. Retardation weakens the potential in each case by R−1 in the far-zone. It is found that by decomposing the octupole moment into its irreducible components of weights-1 and -3 that the former contribution to the DDO potential may be taken to be a higher-order correction to the leading triple dipole energy shift.
Stabilization of charged and neutral colloids in salty mixtures
Authors: Samin Sela , Tsori Yoav
Published: December 2013

We present a mechanism for the stabilization of colloids in liquid mixtures without use of surfactants or polymers. When a suitable salt is added to a solvent mixture, the coupling of the colloid's surface chemistry and the preferential solvation of ions leads to a repulsive force between colloids that can overcome van der Waals attraction. This repulsive force is substantial in a large range of temperatures, mixture composition, and salt concentrations. The increased repulsion due to addition of salt occurs even for charged colloids. This mechanism may be useful in experimental situations where steric stabilization with surfactants or polymers is undesired.
Propagation and oblique collision of ion-acoustic solitary waves in a magnetized dusty electronegative plasma
Authors: El-Labany S. K. , El-Shamy E. F. , Behery E. E.
Published: December 2013

The propagation and oblique collision of ion-acoustic (IA) solitary waves in a magnetized dusty electronegative plasma consisting of cold mobile positive ions, Boltzmann negative ions, Boltzmann electrons, and stationary positive/negative dust particles are studied. The extended Poincaré-Lighthill-Kuo perturbation method is employed to derive the Korteweg-de Vries equations and the corresponding expressions for the phase shifts after collision between two IA solitary waves. It turns out that the angle of collision, the temperature and density of negative ions, and the dust density of opposite polarity have reasonable effects on the phase shift. Clearly, the numerical results demonstrated that the IA solitary waves are delayed after the oblique collision. The current finding of this work is applicable in many plasma environments having negative ion species, such as D- and F-regions of the Earth's ionosphere and some laboratory plasma experiments.
Unexpected behaviour of one Pb monolayer deposited on aluminum oxide thin film grown on Ag(111)
Authors: Vizzini Sébastien , Oughaddou Hamid , Hoarau J. Y. , Biberian J. P. , Bertoglio M. , Aufray B.
Published: December 2013

Using scanning tunneling microscopy (STM), Auger electron spectroscopy, and low energy electron diffraction, we have observed a surprising complete dissolution at room temperature of one lead monolayer deposited by evaporation on an aluminum oxide thin film (∼0.8 nm thick) previously grown on Ag (111). We have observed the quasi-instantaneous diffusion of the lead deposit through the oxide layer to the silver/oxide interface. After the diffusion process, lead atoms form a Moiré superstructure, which is characterized by STM through the oxide layer. This unexpected behavior puts in light the very weak interaction between the aluminum oxide and the silver substrate.
Effect of Ti seed layers on structure of self-organized epitaxial face-centered-cubic-Ag(001) oriented nanodots
Authors: Kamiko M. , Suenaga R. , Koo J.-W. , Nose K. , Kyuno K. , Ha J.-G.
Published: December 2013

The influence of Ti seed layers on the structure of self-organized Ag nanodots, obtained with a Ti seed-layer-assisted thermal agglomeration method, has been investigated. The samples were grown on MgO(001) single crystal substrates by RF magnetron sputter deposition. The samples were deposited at room temperature and post-annealed at 350 °C for 4 h while maintaining the chamber vacuum conditions. The results of atomic force microscopy (AFM) observations indicated that the insertion of the Ti seed layer (0.6–5.0 nm) between the MgO substrate and Ag layer promotes the agglomeration process, forming the nanodot array. Comparisons between the AFM images revealed that the size of the Ag nanodots was increased with an increase in the Ti seed layer thickness. The atomic concentration of the film surface was confirmed by X-ray photoelectron spectroscopy (XPS). The XPS result suggested that the nanodot surface mainly consisted of Ag. Moreover, X-ray diffraction results proved that the initial deposition of the Ti seed layer (0.6–5.0 nm) onto MgO(001) prior to the Ag deposition yielded high-quality fcc-Ag(001) oriented epitaxial nanodots. The optical absorbance spectra of the fabricated Ag nanodots with various Ti seed layer thicknesses were obtained in the visible light range.
SnSe2 field-effect transistors with high drive current
Authors: Su Yang , Ebrish Mona A. , Olson Eric J. , Koester Steven J.
Published: December 2013

SnSe2 field-effect transistors fabricated using mechanical exfoliation are reported. Substrate-gated devices with source-to-drain spacing of 0.5 μm have been fabricated with drive current of 160 μA/μm at T = 300 K. The transconductance at a drain-to-source voltage of Vds = 2 V increases from 0.94 μS/μm at 300 K to 4.0 μS/μm at 4.4 K, while the field-effect mobility increases from 8.6 cm2/Vs at 300 K to 28 cm2/Vs at 77 K. The conductance at Vds = 50 mV shows an activation energy of only 5.5 meV, indicating the absence of a significant Schottky barrier at the source and drain contacts.
Thermal stability and oxidation of layer-structured rhombohedral In3Se4 nanostructures
Authors: Han Guang , Chen Zhi-Gang , Yang Lei , Cheng Lina , Jack Kevin , Drennan John , Zou Jin
Published: December 2013

The thermal stability and oxidation of layer-structured rhombohedral In3Se4 nanostructures have been investigated. In-situ synchrotron X-ray diffraction in a sealed system reveals that In3Se4 has good thermal stability up to 900 °C. In contrast, In3Se4 has lower thermal stability up to 550 or 200 °C when heated in an atmosphere flushed with Ar or in air, respectively. The degradation mechanism was determined to be the oxidation of In3Se4 by O2 in the heating environment. This research demonstrates how thermal processing conditions can influence the thermal stability of In3Se4, suggesting that appropriate heating environment for preserving its structural integrity is required.
Biological role of prolyl 3-hydroxylation in type IV collagen
Authors: Pokidysheva Elena , Boudko Sergei , Vranka Janice , Zientek Keith , Maddox Kerry , Moser Markus , Fässler Reinhard , Ware Jerry , Bächinger Hans Peter
Published: December 2013

Significance

Prolyl 3-hydroxylation is a crucial posttranslational modification of collagens. To investigate the role of prolyl 3-hydroxylase 2 (P3H2) and function of 3-hydroxylation in type IV collagen, we created a KO mouse. Prolyl 3-hydroxylation of type IV collagen is required to avoid an aberrant interaction with the platelet-specific glycoprotein VI (GPVI), resulting in platelet aggregation, thrombosis of the maternal blood, and death of the embryo. Homozygous P3H2-null embryos die before embryonic day 8.5. The lethal phenotype can be rescued by producing double mutants of P3H2 and GPVI. Double nulls are viable and fertile. Thus, 3-hydroxylation of type IV collagen is indispensable for embryonic development in mice. We assign a molecular function for prolyl 3-hydroxyl groups in type IV collagen.
Ohnologs are overrepresented in pathogenic copy number mutations
Authors: McLysaght Aoife , Makino Takashi , Grayton Hannah M. , Tropeano Maria , Mitchell Kevin J. , Vassos Evangelos , Collier David A.
Published: December 2013

Significance

Copy number variants (CNVs) have recently emerged as an important cause of human disorders. Most pathogenic CNVs are large and contain many genes, and identification of the specific disease-causing genes has proven to be challenging. Using an evolutionary genetic approach, we tried to identify such genes through the mapping of ohnologs, genes retained after ancestral whole-genome duplication events. Comparing the proportion of ohnologs between potentially pathogenic and nonpathogenic sets of CNVs, we found that ohnologs are significantly overrepresented in the pathogenic sets. Our results support the hypothesis that ohnologs are ancestral dosage-sensitive elements that may be responsible for some of the deleterious phenotypes observed for CNVs.
miR-218
opposes a critical RTK-HIF pathway in mesenchymal glioblastoma
Authors: Mathew Lijoy K. , Skuli Nicolas , Mucaj Vera , Lee Samuel S. , Zinn Pascal O. , Sathyan Pratheesh , Imtiyaz Hongxia Z. , Zhang Zhongfa , Davuluri Ramana V. , Rao Shilpa , Venneti Sriram , Lal Priti , Lathia Justin D. , Rich Jeremy N. , Keith Brian , Minn Andy J. , Simon M. Celeste
Published: December 2013

Significance

Despite measurable advances in cancer treatment, patients with glioblastoma multiforme (GBM) typically survive only 12–14 mo because of tumor recurrence. Tumor hypoxia has been associated with chemoresistance. We hypothesized that the pronounced repression of microRNA-218 (
miR-218
) observed in samples from patients with highly hypoxic and necrotic GBM contributes to this recurrent phenotype. We demonstrate here that mice harboring intracranial tumors with increased
miR-218
expression exhibit significantly reduced tumor burden and increased survival when challenged with the chemotherapeutic agent temozolomide. Moreover, low
miR-218
levels increase the expression of multiple components of the receptor tyrosine kinase signaling pathway, which promote the activation of hypoxia-inducible factor. The identification of the molecular bases for
miR-218
-mediated chemoresistance should promote the development of targeted therapies.
Rationale and mechanism for the low photoinactivation rate of bacteria in plasma
Authors: Chen Jie , Cesario Thomas C. , Rentzepis Peter M.
Published: December 2013

Significance

Human plasma is often decontaminated by methylene blue (MB) photoexcitation; however, the rate of bacterial photoinactivation in plasma has been found to be lower by about an order of magnitude than that in PBS or water. We attribute this low inactivation rate to the bleaching of the 660-nm band of MB by the electrophilic attack of the S–H group of cysteine on the central nitrogen atom. Further investigations are aimed at the development of means that prevent bleaching of MB and allow its photoinactivation of bacteria and other pathogens.
The Opportunity Cost of Travel Time as a Noisy Wage Fraction
Authors: Larson Douglas M. , Lew Daniel K.
Published: December 2013

Few issues are more important to welfare estimation with recreation demand models than the specification of the opportunity cost of travel time. The two most common approaches to specifying this cost treat it as a fixed fraction of the recreationist's wage, and either estimate the fraction (done infrequently) or assume it takes some value (done commonly), with references to results from the commute time literature used to justify the latter. However, these approaches lack firm conceptual rationales, and the consequences of using them are not fully understood. Recognizing that information limitations often preclude more general approaches, we use a joint recreation travel‐labor supply model to show that under relatively modest assumptions the opportunity cost of travel time can be expressed as a wage fraction with noise. This formulation is straightforward to implement as part of random parameters‐based recreation demand models. We then evaluate the welfare consequences of using the two approaches noted above, which are special cases of the noisy wage fraction specification. Our results suggest that the more critical restriction to relax in opportunity cost of travel time specifications is the absence of noise, rather than the specific level of the wage fraction.
Foreclosures and Invasive Insect Spread: The Case of Asian Citrus Psyllid
Authors: Richards Timothy J. , Shanafelt David W. , Fenichel Eli P.
Published: December 2013

Human economic activity is considered to be an important factor in exacerbating the speed of invasive species spread, but may also play an important role in preventing it. In this study, we investigate the role of home foreclosure in the spread of Asian Citrus Psyllid (ACP, Diaphorina citri Kuwayama) throughout residential areas of Southern California. We find that foreclosures are indeed a significant factor in explaining ACP spread, even after controlling for other human and environmental effects. Our results suggest that human economic activity may be more important in controlling the spread of invasive species than previously realized, and that the external costs of the foreclosure problem may also be underestimated.
Angel Investment and Collective Agricultural Marketing: The Case of the Minnesota Food Network
Authors: Damon Amy , Nicola Diego
Published: December 2013

The Minnesota Food Network is a limited liability company comprised of 52 farmers producing a variety of high‐quality, sustainably produced agricultural products in southern Minnesota. The network's goal is to develop a regional food system to provide locally grown food at a price that “is fair” to both consumers and producers. This case outlines the challenges that the network faces in their efforts to expand to take advantage of a market opportunity. One of their biggest challenges is that they face high operating costs because of their disaggregated distribution system and need to purchase a distribution and storage facility and two vehicles. They will fund the purchase of a building through an angel investor. An angel investor is necessary because the network cannot sustain traditional loan payments in its current form. Students are asked to consider a number of questions pertaining to the decisions in this case outlined in the final section of the case study.
Discriminative motif optimization based on perceptron training
Authors: Patel Ronak Y. , Stormo Gary D.
Published: December 2013

Motivation: Generating accurate transcription factor (TF) binding site motifs from data generated using the next-generation sequencing, especially ChIP-seq, is challenging. The challenge arises because a typical experiment reports a large number of sequences bound by a TF, and the length of each sequence is relatively long. Most traditional motif finders are slow in handling such enormous amount of data. To overcome this limitation, tools have been developed that compromise accuracy with speed by using heuristic discrete search strategies or limited optimization of identified seed motifs. However, such strategies may not fully use the information in input sequences to generate motifs. Such motifs often form good seeds and can be further improved with appropriate scoring functions and rapid optimization.

Results: We report a tool named discriminative motif optimizer (DiMO). DiMO takes a seed motif along with a positive and a negative database and improves the motif based on a discriminative strategy. We use area under receiver-operating characteristic curve (AUC) as a measure of discriminating power of motifs and a strategy based on perceptron training that maximizes AUC rapidly in a discriminative manner. Using DiMO, on a large test set of 87 TFs from human, drosophila and yeast, we show that it is possible to significantly improve motifs identified by nine motif finders. The motifs are generated/optimized using training sets and evaluated on test sets. The AUC is improved for almost 90% of the TFs on test sets and the magnitude of increase is up to 39%.

Availability and implementation:  DiMO is available at http://stormo.wustl.edu/DiMO

Contact:  rpatel@genetics.wustl.edu, ronakypatel@gmail.com
Information in the Mark and the Marketplace: A Multivocal Account
Authors: Duguid Paul
Published: December 2013

Trademark theory implicitly assumes that laws favoring the interests of the producer will inevitably serve the interests of the consumer. Such a claim justifies the way that trademark law privileges the voice of the producer in the marketplace. Historical work has tended to endorse this view, explaining the development of trademarks and trademark law in terms of the information needed for consumers in the modern marketplace. Taking both a historical and “informational” perspective, this essay argues that the producer’s and the consumer’s interests do not so easily align. It speculates that a less varnished history of the mark shows more of a struggle between producers, who seek to have their voice heard without dissent, and consumers, who often want to find alternative yet informed voices to endorse or qualify the information provided by the mark. This alternative view would help explain why, as the paper seeks to show, despite conventional evolutionary narratives, the history of trademarking in the United States is in fact far from linear.