bluuebunny/crossref_metadata_2025 huggingface dataset:
Prevalence and elimination of sibling neurite convergence in motor units supplying neonatal and adult mouse skeletal muscle
Authors: Teriakidis Adrianna , Willshaw David J. , Ribchester Richard R.
Published: March 2012

During development, neurons form supernumerary synapses, most of which are selectively pruned leading to stereotyped patterns of innervation. During the development of skeletal muscle innervation, or its regeneration after nerve injury, each muscle fiber is transiently innervated by multiple motor axon branches but eventually by a single branch. The selective elimination of all but one branch is the result of competition between the converging arbors. It is thought that motor neurons initially innervate muscle fibers randomly, but that axon branches from the same neuron (sibling branches) do not converge to innervate the same muscle fiber. However, random innervation would result in many neonatal endplates that are co‐innervated by sibling branches. To investigate whether this occurs we examined neonatal levator auris longus (LAL) and 4th deep lumbrical (4DL) muscles, as well as adult reinnervated deep lumbrical muscles (1–4) in transgenic mice expressing yellow fluorescent protein (YFP) as a reporter. We provide direct evidence of convergence of sibling neurites within single fluorescent motor units, both during development and during regeneration after nerve crush. The incidence of sibling neurite convergence was 40% lower in regeneration and at least 75% lower during development than expected by chance. Therefore, there must be a mechanism that decreases the probability of its occurrence. As sibling neurite convergence is not seen in normal adults, or at later timepoints in regeneration, synapse elimination must also remove convergent synaptic inputs derived from the same motor neuron. Mechanistic theories of synaptic competition should now accommodate this form of isoaxonal plasticity. J. Comp. Neurol., 520:3203–3216, 2012. © 2012 Wiley Periodicals, Inc.
Distinct retinohypothalamic innervation patterns predict the developmental emergence of species‐typical circadian phase preference in nocturnal Norway rats and diurnal nile grass rats
Authors: Todd William D. , Gall Andrew J. , Weiner Joshua A. , Blumberg Mark S.
Published: March 2012

How does the brain develop differently to support nocturnality in some mammals, but diurnality in others? To answer this question, one might look to the suprachiasmatic nucleus (SCN), which is entrained by light via the retinohypothalamic tract (RHT). However, because the SCN is more active during the day in all mammals studied thus far, it alone cannot determine circadian phase preference. In adult Norway rats (Rattus norvegicus), which are nocturnal, the RHT also projects to the ventral subparaventricular zone (vSPVZ), an adjacent region that expresses an in‐phase pattern of SCN‐vSPVZ neuronal activity. In contrast, in adult Nile grass rats (Arvicanthis niloticus), which are diurnal, an anti‐phase pattern of SCN‐vSPVZ neuronal activity is expressed. We hypothesized that these species differences result in part from a weak or absent RHT‐to‐vSPVZ projection in grass rats. Here, using a developmental comparative approach, we assessed species differences in behavior, hypothalamic activity, and RHT anatomy. We report that a robust retina‐to‐vSPVZ projection develops in Norway rats around the end of the second postnatal week when nocturnal wakefulness and the in‐phase pattern of neuronal activity emerge. In grass rats, however, such a projection does not develop and the emergence of the anti‐phase pattern during the second postnatal week is accompanied by increased diurnal wakefulness. When considered within the context of previously published reports on RHT projections in a variety of species, the current findings suggest that how and when the retina connects to the hypothalamus differentially shapes brain and behavior to produce animals that occupy opposing temporal niches. J. Comp. Neurol., 520:3277–3292, 2012. © 2012 Wiley Periodicals, Inc.
Age‐related plasticity in the synaptic ultrastructure of neurons in the mushroom body calyx of the adult honeybee Apis mellifera
Authors: Groh Claudia , Lu Zhiyuan , Meinertzhagen Ian A. , Rössler Wolfgang
Published: March 2012

The mushroom bodies are high‐order sensory integration centers in the insect brain. In the honeybee, their main sensory input regions are large, doubled calyces with modality‐specific, distinct sensory neuropil regions. We investigated adult structural plasticity of input synapses in the microglomeruli of the olfactory lip and visual collar. Synapsin‐immunolabeled whole‐mount brains reveal that during the natural transition from nursing to foraging, a significant volume increase in the calycal subdivisions is accompanied by a decreased packing density of boutons from input projection neurons. To investigate the associated ultrastructural changes at pre‐ and postsynaptic sites of individual microglomeruli, we employed serial‐section electron microscopy. In general, the membrane surface area of olfactory and visual projection neuron boutons increased significantly between 1‐day‐old bees and foragers. Both types of boutons formed ribbon and non‐ribbon synapses. The percentage of ribbon synapses per bouton was significantly increased in the forager. At each presynaptic site the numbers of postsynaptic partners—mostly Kenyon cell dendrites—likewise increased. Ribbon as well as non‐ribbon synapses formed mainly dyads in the 1‐day‐old bee, and triads in the forager. In the visual collar, outgrowing Kenyon cell dendrites form about 140 contacts upon a projection neuron bouton in the forager compared with only about 95 in the 1‐day‐old bee, resulting in an increased divergence ratio between the two stages. This difference suggests that synaptic changes in calycal microcircuits of the mushroom body during periods of altered sensory activity and experience promote behavioral plasticity underlying polyethism and social organization in honeybee colonies. J. Comp. Neurol. 520:3509–3527, 2012. © 2012 Wiley Periodicals, Inc.
Glycine in 1‐Butyl‐3‐Methylimidazolium Acetate and Trifluoroacetate Ionic Liquids: Effect of Fluorination and Hydrogen Bonding
Authors: Podgoršek Ajda , Macchiagodena Marina , Ramondo Fabio , Costa Gomes Margarida F. , Pádua Agílio A. H.
Published: March 2012

The solvation of glycine in two ionic liquids (ILs), namely, 1‐butyl‐3‐methylimidazolium acetate, [C1C4Im][OAc], and 1‐butyl‐3‐methylimidazolium trifluoroacetate, [C1C4Im][TFA], was studied by a combination of experimental and theoretical methods. The solubility of glycine in both ILs was determined at 333.15 K to be (8.1±0.5) and (1.0±0.5) wt % in [C1C4Im][OAc] and [C1C4Im][TFA], respectively. By IR spectroscopy it was found that, when dissolved in the ILs, glycine was mainly present in its zwitterionic form. Structural and energetic aspects of the solvation of glycine in the ILs and in mixtures of ILs and water were investigated by ab initio calculations and molecular dynamic simulations. It was observed that the firstly solvation shell around glycine consisted predominantly of acetate or trifluoroacetate anions, which formed hydrogen bonds either with the carboxylic group of neutral glycine or with the protonated ammonium group of the zwitterionic form. When water is present in the solutions, hydrogen bonds between water and the anion prevail. The overall energy of the system was decomposed into its components between pairs of species. It was established that the dominant contribution to the interaction energy between glycine and the IL was due to hydrogen bonds with the anions and the statistics of hydrogen bonds were analysed.
Chloride Transport
Authors: Edwards John C.
Published: March 2012

Chloride transport along the nephron is one of the key actions of the kidney that regulates extracellular volume and blood pressure. To maintain steady state, the kidney needs to reabsorb the vast majority of the filtered load of chloride. This is accomplished by the integrated function of sequential chloride transport activities along the nephron. The detailed mechanisms of transport in each segment generate unique patterns of interactions between chloride and numerous other individual components that are transported by the kidney. Consequently, chloride transport is inextricably intertwined with that of sodium, potassium, protons, calcium, and water. These interactions not only allow for exquisitely precise regulation but also determine the particular patterns in which the system can fail in disease states. © 2012 American Physiological Society.Compr Physiol2:1061‐1092, 2012.
Skeletal Muscle Fatigue
Authors: Kent‐Braun Jane A. , Fitts Robert H. , Christie Anita
Published: March 2012

Skeletal muscle fatigue is defined as the fall of force or power in response to contractile activity. Both the mechanisms of fatigue and the modes used to elicit it vary tremendously. Conceptual and technological advances allow the examination of fatigue from the level of the single molecule to the intact organism. Evaluation of muscle fatigue in a wide range of disease states builds on our understanding of basic function by revealing the sources of dysfunction in response to disease. © 2012 American Physiological Society.Compr Physiol2:997‐1044, 2012.
Cognitive Remediation and Emotion Skills Training for Anorexia Nervosa: An Observational Study Using Neuropsychological Outcomes
Authors: Davies Helen , Fox John , Naumann Ulrike , Treasure Janet , Schmidt Ulrike , Tchanturia Kate
Published: March 2012

Objective

This study aims to evaluate a novel and brief skills‐based therapy for in‐patients with anorexia nervosa, which addressed ‘cold’ and ‘hot’ cognition.

Method

Eighty one adults with anorexia nervosa were recruited from two eating disorder in‐patient units. In one unit, patients received 10 sessions of cognitive remediation and emotion skills training (CREST) plus treatment as usual. In the other, patients received treatment as usual only. Primary outcomes were body mass index and neuropsychological performance scores.

Results

Both groups improved significantly in body mass index and cognitive flexibility. The CREST group also improved on central coherence. Neither group improved significantly on emotion‐processing tasks, although the CREST group did show a larger magnitude of change.

Conclusion

Improvement in ‘cold’ cognition was achieved in a short period, whereas emotion‐processing difficulties might take longer and more therapeutic work to change. Given that effect sizes in the CREST group were larger for the emotion‐processing tasks, improved power may benefit future studies. Copyright © 2012 John Wiley & Sons, Ltd and Eating Disorders Association.
Oral and oropharyngeal squamous cell carcinoma in young patients: The Netherlands Cancer Institute experience
Authors: van Monsjou Hester S. , Lopez–Yurda Marta I. , Hauptmann Michael , van den Brekel Michiel W. M. , Balm Alfons J. M. , Wreesmann Volkert B.
Published: March 2012

Background

Head and neck squamous cell carcinoma (HNSCC) mainly affects patients between the fifth and seventh decade of life but is increasingly seen in young patients (<40 years old). Controversy exists in the literature regarding outcomes for younger patients with HNSCC.

Methods

A retrospective cohort analysis was performed comparing survival of 54 early‐onset (<40 years) and 1708 older patients with oral and oropharyngeal squamous cell carcinomas (SCC) treated at The Netherlands Cancer Institute between 1977 and 2008. Survival analysis was performed using univariable and multivariable weighted Cox proportional hazards regression. The primary endpoint for the survival analysis was disease‐specific survival (DSS).

Results

There was no difference in DSS between patients who were 40 years or younger and those older than 40 years (p = .878), although young patients had significantly better overall survival (OS).

Conclusion

In this series, patients younger than 40 years with oral and oropharyngeal SCC showed no significant difference in DSS compared with patients older than 40 years, even when adjusted for tobacco and alcohol consumption. © 2012 Wiley Periodicals, Inc. Head Neck, 2013
Thyroid disease associated with cowden syndrome: A meta‐analysis
Authors: Hall Joseph E. , Abdollahian Davood J. , Sinard Robert J.
Published: March 2012

Background

We investigated the pathology and surgical management of thyroid disease in patients with Cowden syndrome (CS).

Methods

A query of the PubMed database between 2001 and January 2010 was performed using the terms “cowden syndrome OR cowden's syndrome OR cowden disease OR cowden's disease.” Original articles, reviews, case reports, and case series were included. Articles were excluded if they were not written in English, did not present case/cases of CS, or did not include patient information to qualify for a diagnosis of CS. Ninety‐five articles met the inclusion and exclusion criteria. A total of 181 cases were analyzed.

Results

Of the 181 patients, 99 female (54.7%) and 77 male patients (42.5%) had sex reported. The age at presentation ranged from 3 days to 78 years. Ninety‐six patients (96/181, 53.0%) were reported to have thyroid disease. Surgical management of thyroid disease was performed in 80.2% (77/96) of patients with thyroid disease, with total thyroidectomy being the most common operation reported (23/77, 29.9%). Thyroid pathology reported with CS patients included goiter (39/96, 40.6%), adenoma (24/96, 25%), unknown/unspecified pathology (8/96, 8.3%), follicular carcinoma (7/96, 7.3%), thyroiditis (7/96, 7.3%), papillary carcinoma (6/96, 6.3%), cancer (unknown type) (3/96, 3.1%), medullary carcinoma (1/96, 1%), and hyperthyroidism (1/96, 1%).

Conclusion

Careful monitoring of thyroid disease in CS patients is imperative. © 2012 Wiley Periodicals, Inc. Head Neck, 2013
Transcriptomic analysis of the woodchuck model of chronic hepatitis B
Authors: Fletcher Simon P. , Chin Daniel J. , Ji Yongmei , Iniguez Leonardo A. , Taillon Bruce , Swinney David C. , Ravindran Palanikumar , Cheng Donavan T. , Bitter Hans , Lopatin Uri , Ma Han , Klumpp Klaus , Menne Stephan
Published: March 2012

The Eastern woodchuck (
Marmota monax
) is naturally infected with woodchuck hepatitis virus (WHV), a hepadnavirus closely related to the human hepatitis B virus (HBV). The woodchuck is used as an animal model for studying chronic hepatitis B (CHB) and HBV-associated hepatocellular carcinoma (HCC) in humans, but the lack of sequence information has hitherto precluded functional genomics analysis. To address this major limitation of the model, we report here the sequencing, assembly, and annotation of the woodchuck transcriptome, together with the generation of custom woodchuck microarrays. Using this new platform, we characterized the transcriptional response to persistent WHV infection and WHV-induced HCC. This revealed that chronic WHV infection, like HBV, is associated with (1) a limited intrahepatic type I interferon response; (2) intrahepatic induction of markers associated with T cell exhaustion; (3) elevated levels of

suppressor of cytokine signaling 3 (SOCS3)

in the liver; and (4) intrahepatic accumulation of neutrophils. Underscoring the translational value of the woodchuck model, this study also determined that WHV-induced HCC shares molecular characteristics with a subtype of human HCC with poor prognosis.

Conclusion:

Our data establish the translational value of the woodchuck model and provide new insight into immune pathways which may play a role either in the persistence of HBV infection or the sequelae of CHB.
Effect of colesevelam on liver fat quantified by magnetic resonance in nonalcoholic steatohepatitis: A randomized controlled trial
Authors: Le Thuy-Anh , Chen Joshua , Changchien Christopher , Peterson Michael R. , Kono Yuko , Patton Heather , Cohen Benjamin L. , Brenner David , Sirlin Claude , Loomba Rohit
Published: March 2012

Bile acid sequestrants (BAS) lower plasma low density lipoprotein levels and improve glycemic control. Colestimide, a BAS, has been claimed by computed tomography to reduce liver fat. Therefore, we examined the efficacy of colesevelam, a potent BAS, to decrease liver fat in patients with biopsy-proven nonalcoholic steatohepatitis (NASH). Liver fat was measured by a novel magnetic resonance imaging (MRI) technique, the proton-density-fat-fraction (PDFF), as well as by conventional MR spectroscopy (MRS). Fifty patients with biopsy-proven NASH were randomly assigned to either colesevelam 3.75 g/day orally or placebo for 24 weeks. The primary outcome was change in liver fat as measured by MRI-PDFF in colocalized regions of interest within each of the nine liver segments. Compared with placebo, colesevelam increased liver fat by MRI-PDFF in all nine segments of the liver with a mean difference of 5.6% (
P

= 0.002). We cross-validated the MRI-PDFF-determined fat content with that assessed by colocalized MRS; the latter showed a mean difference of 4.9% (
P

= 0.014) in liver fat between the colesevelam and the placebo arms. MRI-PDFF correlated strongly with MRS-determined hepatic fat content (
r

2 = 0.96,
P

< 0.0001). Liver biopsy assessment of steatosis, cellular injury, and lobular inflammation did not detect any effect of treatment.

Conclusion:

Colesevelam increases liver fat in patients with NASH as assessed by MRI as well as MRS without significant changes seen on histology. Thus, MRI and MRS may be better than histology to detect longitudinal changes in hepatic fat in NASH. Underlying mechanisms and whether the small MR-detected increase in liver fat has clinical consequences is not known.
Improving SEM Inspection Performance in Semiconductor Manufacturing Industry
Authors: Lin Chih‐Long , Chen Fu‐Sheng , Twu Li‐Jen , Wang Mao‐Jiun J.
Published: March 2012

Scanning electron microscope (SEM) station is one of the major quality control tasks in wafer manufacturing process. During the process of examining defects on a screen for a certain period of time, SEM inspectors frequently complain about visual fatigue problems. The purpose of the study was to evaluate the effect of wafer‐coating condition (noncoating treatment and gold‐coating treatment) and liquid crystal display (LCD) monitor size (14‐inch and 19‐inch monitor) from the aspects of objective visual fatigue measures (NPA and CFF), subjective eye fatigue rating, and inspection performance. Twelve SEM inspectors participated in this experiment. The results indicated that the treatment of gold‐coating wafer showed significant difference on reducing objective visual fatigue in NPA and CFF change. Using a 19‐inch LCD monitor also demonstrated the effect on reducing eye fatigue as well as improving inspection performance. The improvement of using a gold‐coating treatment wafer and a 19‐inch LCD monitor to reduce SEM inspectors' visual fatigue and to increase inspection performance is thus recommended. © 2012 Wiley Periodicals, Inc.
Prevalence and associated risk factors of low‐back pain in textile fishing net manufacturing
Authors: Keawduangdee Petcharat , Puntumetakul Rungthip , Chatchawan Uraiwon , Kaber David , Siritaratiwat Wantana
Published: March 2012

This study examined the 7‐day prevalence of low‐back pain (LBP; i.e., pain within the preceding week of the survey) and identified associated factors, including working posture, for a population of fishing net assembly workers. LBP is a serious problem in manual work with high prevalence and affects worker absenteeism. A cross‐sectional survey study was conducted among textile fish net industrial workers using a structured questionnaire (hand delivered by researchers and independently completed by workers). The 7‐day prevalence of LBP in this study was 68.6% (95% confidence interval [CI]: 65 to 72%). Work factors significantly related to LBP included prolonged standing and walking. Workers 35 years old or greater were significantly more likely to experience LBP within the past 7 days preceding the survey than were those 34 years old or less (adjusted odds ratio [ORadj] = 4.9; 95% CI: 2.4 to 10.3; p = .0001). Other significant factors associated with LBP included posture position, specifically stooping (ORadj = 1.6; 95% CI: 1.0 to 2.3; p = .033), lifting (ORadj = 1.6; 95% CI: 1.1 to 2.4; p = .025), and high concentration jobs (ORadj = 1.9; 95% CI: 1.3 to 2.7; p = .001), respectively. LBP among textile fish net workers is a serious problem meriting ergonomic evaluation and design of control measures for reducing worker exposure to risk factors. Work characteristics were more significantly associated with LBP than were individual characteristics. Factories need to consider adjusting work conditions to prevent worker low‐back injuries. © 2012 Wiley Periodicals, Inc.
Integrating novel signaling pathways involved in erythropoiesis
Authors: Ingley Evan
Published: March 2012

Many extrinsic and intrinsic factors control the development of red blood cells from committed progenitors, with the Erythropoietin‐receptor (Epo‐R) signaling network being the primary controlling molecular hub. Although much is understood about erythroid signaling pathways, new and intriguing factors that influence different aspects of erythroid cell development are still being uncovered. New extrinsic effectors include hypoxia and polymeric IgA1 (pIgA1), and new Epo‐R signaling pathway components include Lyn/Cbp and Lyn/Liar. Hypoxia directly activates committed erythroid progenitors to expand, whereas pIgA1 activates the Akt and MAP‐Kinase (MAPK) pathways through transferrin receptors on more mature erythroid cells. The Lyn/Cbp pathway controls the activity and protein levels of Lyn through recruitment of Csk and SOCS1, as well as feeding into the control of other pathways mediated by recruitment of ras‐GAP, PI3‐kinase, PLCγ, Fes, and EBP50. Nuclear/cytoplasmic shuttling of Lyn and other signaling molecules is influenced by Liar and results in regulation of their intersecting signaling pathways. The challenge of future research is to flesh out the details of these new signaling regulators/networks and integrate their influences during the different stages of erythropoiesis. 2012 IUBMB IUBMB Life, 2012
Serum response factor regulates bone formation via IGF-1 and Runx2 signals
Authors: Chen Jianfeng , Yuan Kaiyu , Mao Xia , Miano Joseph M , Wu Hui , Chen Yabing
Published: March 2012

Serum response factor (SRF) plays vital roles in numerous cellular processes; however, the physiological function of SRF in skeletal tissue remains unknown. In several organ systems, SRF regulates the expression of insulin-like growth factor-1 (IGF-1), which is crucial for normal development of mineralized skeleton and bone remodeling throughout life. Here, we show that conditional deletion of SRF in osteoblasts by osteocalcin-Cre generated viable mice with normal body size and body weight. Compared with normal siblings, osteoblast-specific SRF-deficient adult mice exhibited a marked decrease in bone mineral density and bone formation rate. Deletion of SRF in primary mouse calvarial osteoblasts reduced cell differentiation and mineralization in vitro. This was accompanied by a decrease in IGF-1 expression and secretion. Addition of IGF-1 in the culture media enhanced osteoblast differentiation in control cells and partially restored the mineralization defect of SRF-deficient cells, supporting an important role of SRF in regulating IGF-1 and IGF-1–mediated osteoblast differentiation. IGF-1–induced Akt activation was inhibited in SRF-deficient calvarial cells and enhanced in the SRF overexpressed cells. In addition, SRF deficiency decreased the transcriptional activity of Runx2, the key transcription factor for osteogenesis. Overexpression of SRF induced Runx2 transactivity in control cells and restored Runx2 transactivity in the SRF-deficient cells. Taken together, we conclude that SRF is important for IGF-1–induced osteoblast differentiation and mineralization via regulating IGF-1 expression and Runx2 transactivity. © 2012 American Society for Bone and Mineral Research.
Absence of sclerostin adversely affects B-cell survival
Authors: Cain Corey J , Rueda Randell , McLelland Bryce , Collette Nicole M , Loots Gabriela G , Manilay Jennifer O
Published: March 2012

Increased osteoblast activity in sclerostin-knockout (Sost−/−) mice results in generalized hyperostosis and bones with small bone marrow cavities resulting from hyperactive mineralizing osteoblast populations. Hematopoietic cell fate decisions are dependent on their local microenvironment, which contains osteoblast and stromal cell populations that support both hematopoietic stem cell quiescence and facilitate B-cell development. In this study, we investigated whether high bone mass environments affect B-cell development via the utilization of Sost−/− mice, a model of sclerosteosis. We found the bone marrow of Sost−/− mice to be specifically depleted of B cells because of elevated apoptosis at all B-cell developmental stages. In contrast, B-cell function in the spleen was normal. Sost expression analysis confirmed that Sost is primarily expressed in osteocytes and is not expressed in any hematopoietic lineage, which indicated that the B-cell defects in Sost−/− mice are non-cell autonomous, and this was confirmed by transplantation of wild-type (WT) bone marrow into lethally irradiated Sost−/− recipients. WT→Sost−/− chimeras displayed a reduction in B cells, whereas reciprocal Sost−/−→WT chimeras did not, supporting the idea that the Sost−/− bone environment cannot fully support normal B-cell development. Expression of the pre-B-cell growth stimulating factor, Cxcl12, was significantly lower in bone marrow stromal cells of Sost−/− mice, whereas the Wnt target genes Lef-1 and Ccnd1 remained unchanged in B cells. Taken together, these results demonstrate a novel role for Sost in the regulation of bone marrow environments that support B cells. © 2012 American Society for Bone and Mineral Research.
Transcript characteristic of myostatin in sheep fibroblasts
Authors: Lu Jian , Ren Hangxing , Sheng Xihui , Zhang Xiaoning , Li Shangang , Zhao Fuping , Zhou Xinlei , Zhang Li , Wei Caihong , Ding Jiatong , Li Bichun , Du Lixin
Published: March 2012

Myostatin, a secreted growth factor highly expressed in skeletal muscle, negatively regulates skeletal muscle growth and differentiation. Recently, myostatin is emerged as a potential target for anti‐atrophy and anti‐fibrotic therapies. Therefore, to investigate the regulation of myostatin in sheep adult fibroblasts, we used the RNA interference mediated by lentiviral vector to gene silence myostatin. Simultaneously, we also had constructed the sheep myostatin overexpression vector to further explore the function of myostatin in fibroblasts. The results here demonstrated that the lentiviral vector could significantly reduce myostatin gene both at mRNA and protein level by 71% and 67%, respectively (P < 0.01). Inhibition of myostatin also resulted in a remarkable increase of activin receptor 2B (ACV2B), p21, PPARγ, leptin, C/EBPβ, and MEF2A expression, and a decrease of Akt1, CDK2, MEF2C, and Myf5 expression. Ectopic myostatin mRNA and protein were also present in the fibroblasts transfection. Furthermore, we observed that overexpression of myostatin contributed to an increase of Akt1, CDK2, Myf5 and PPARγ, and a decrease of p21, C/EBPα and leptin at the transcript level. These results suggested that myostatin positively regulated Akt1, CDK2, Myf5, leptin, and C/EBPα, but negatively regulated p21 mRNA expression in adult fibroblasts, and it also expanded our understanding of the regulation mechanism of myostatin. Moreover, the lentiviral system inactivated myostatin gene in fibroblasts would be used to generate transgenic sheep and to ameliorate muscle fibrosis and atrophy by gene therapy in the future. J. Cell. Biochem. 113: 2652–2660, 2012. © 2012 Wiley Periodicals, Inc.
Interferon regulatory factor‐1 as a positive regulator for high glucose‐induced proliferation of vascular smooth muscle cells
Authors: Yu Sun , Xi Zhang , Hai‐Yan Chen , Ya‐Li Chi , Shao‐Hu Xiong , Chuan‐Sen Zhang , Xiang‐Qun Yang , Jin‐Ping Guo , Hai‐Yan Lin , Lei Dong
Published: March 2012

High glucose‐induced proliferation of vascular smooth muscle cells (VSMCs) plays an important role in the development of diabetic vascular diseases. However, molecular mediators responding for the proliferation of VSMCs remain to be determined. In this study, VSMCs were isolated from the rat thoracic aorta, and two cell models with Irf‐1 knockdown and overexpression were established by transfecting cells with pGCsi‐FU‐Irf‐1 and pGC‐FU‐Irf‐1, respectively. Subsequently, high glucose was added to cells to induce proliferation. Proliferation assays were performed to see whether Irf‐1 was involved in high glucose‐induced proliferation of VSMCs. In addition, the expression of Irf‐1 was detected in VSMCs stimulated with high glucose and the thoracic aorta of diabetic rats to confirm the relationship between Irf‐1 expression and the proliferation of hyperglycemia‐dependent VSMCs. The results showed that Irf‐1 expression was significantly higher in the thoracic aorta of diabetic rats and VSMCs stimulated with high glucose than that in nondiabetic rats and untreated cells. Overexpression of Irf‐1 accelerated the proliferation of VSMCs, and down‐regulation of Irf‐1 expression significantly depressed the proliferative ability of VSMCs under high‐glucose conditions, indicating that Irf‐1 was a positive regulator for high glucose‐induced proliferation of VSMCs. It could be presumed that Irf‐1 is associated with the accelerated proliferation of VSMCs in diabetic vascular diseases and may prove to be a potential target gene for disease treatment. J. Cell. Biochem. 113: 2671–2678, 2012. © 2012 Wiley Periodicals, Inc.
Assessment of intermolecular interactions at three sites of the arylalkyne in phenylacetylene‐containing lithium‐bonded complexes: Ab initio and QTAIM studies
Authors: Zeng Yanli , Zhu Min , Li Xiaoyan , Zheng Shijun , Meng Lingpeng
Published: March 2012

The intermolecular interactions existing at three different sites between phenylacetylene and LiX (X = OH, NH2, F, Cl, Br, CN, NC) have been investigated by means of second‐order Møller−Plesset perturbation theory (MP2) calculations and quantum theory of “atoms in molecules” (QTAIM) studies. At each site, the lithium‐bonding interactions with electron‐withdrawing groups (F, Cl, Br, CN, NC) were found to be stronger than those with electron‐donating groups (OH and NH2). Molecular graphs of C6H5CCH···LiF and πC6H5CCH···LiF show the same connectional positions, and the electron densities at the lithium bond critical points (BCPs) of the πC6H5CCH···LiF complexes are distinctly higher than those of the σC6H5CCH···LiF complexes, indicating that the intermolecular interactions in the C6H5CCH···LiX complexes can be mainly attributed to the π‐type interaction. QTAIM studies have shown that these lithium‐bond interactions display the characteristics of “closed‐shell” noncovalent interactions, and the molecular formation density difference indicates that electron transfer plays an important role in the formation of the lithium bond. For each site, linear relationships have been found between the topological properties at the BCP (the electron density ρb, its Laplacian ∇2ρb, and the eigenvalue λ3of the Hessian matrix) and the lithium bond lengthd(Li‐bond). The shorter the lithium bond lengthd(Li‐bond), the larger ρb, and the stronger the π···Li bond. The shorterd(Li‐bond), the larger ∇2ρb, and the greater the electrostatic character of the π···Li bond. © 2012 Wiley Periodicals, Inc.
Assessment of ab initio MP2 and density functionals for characterizing the potential energy profiles of the SN2 reactions at N center
Authors: Yu Feng
Published: March 2012

The potential energy profiles of five selected bimolecular nucleophilic substitution (SN2) reactions at nitrogen (N) center have been reinvestigated with the CCSD(T), G3[MP2,CCSD(T)], MP2, and some density functional methods. The basis sets of 6‐31+G(d,p) and 6‐311+G(3d,2p) are used for the MP2 and density functional calculations. Taking the relative energies at the CCSD(T)/CBS level of theory as benchmarks, we recommend the MP2, B97‐K, B2K‐PLYP, BMK, ωB97X‐D, M06‐2X, M05‐2X, CAM‐B3LYP, M08‐SO, and ωB97X methods to generally characterize the potential energy profiles for the SN2 reactions at N center. Furthermore, these recommended methods with the relatively small 6‐31+G(d,p) basis set may also be used to perform direct classical trajectory simulations to uncover the dynamic behaviors of the SN2 reactions at N center. © 2012 Wiley Periodicals, Inc.
Droughts and their social perception in the mass media (southern Spain)
Authors: Ruiz Sinoga Jose Damian , León Gross Teodoro
Published: March 2012

In the Mediterranean environment, drought is one of the extreme phenomena that has most direct consequences and complexity. It also has a direct social impact through the mass media, whose analysis, typology and characterization should be a priority in strategies to plan and mitigate effects. The appearance of droughts is slow, their occurrence is often not recognized until human activity and the environment have already been significantly affected, and drought effects persist for a long time after the drought has ended. The spatial distribution of droughts is highly complex, and significant variation in drought conditions is common between different locations. This makes it difficult to identify similar regions, especially in areas of climate transition, where the atmospheric influences are complex. This is the situation in the Iberian Peninsula (particularly the south of the peninsula), which straddles both temperate and sub‐tropical climates and in which precipitation is highly variable and spatial variability is substantial. In this study, we analysed rainfall anomalies (Standardized Precipitation Index, SPI) over the last 50 years at four representative meteorological stations in southern Spain, two on the coast (Málaga and Algarrobo) and two at the headwaters of river basins regulated by dams (Antequera and Periana). The aims of the study were to (1) analyse the types of drought, and their frequency and intensity and (2) establish the dynamics and evolution of the social perception of droughts in the context of global change, brought about by the communications media. The results showed the SPI was a useful tool for identifying dry anomalies that may feature in our field of study of meteorological and hydrological drought, depending on its duration. Meteorological drought impact on the eco‐geomorphological system is common and has had a particular development since the 1980s. Hydrological droughts are those that have had the greatest effect on water reserves, particularly when they occur in the headwaters of the watershed covered by reservoirs. Their importance has increased since the 1980s. Determination of drought periods and its impact mass media could have extraordinary relevance as a mechanism to establish the levels of awareness on sustainable use of resources. For future research, other socioeconomic and demographic variables should be considered to know the link between drought and water deficit. Copyright © 2012 Royal Meteorological Society
Isolated NAnoparticle Raman Spectroscopy
Authors: Lorite I. , del Campo A. , Romero J. J. , Fernández J. F.
Published: March 2012

Coupling of confocal Raman microscopy and atomic force microscopy provides an experimental tool to perform isolated nanoparticle Raman spectroscopy on Co3O4 nanoparticles dispersed on Al2O3 microparticles, avoiding the use of solvents or polymeric additives. Single Co3O4 nanoparticles showed similar Raman spectrum to that of single crystal or bulk systems. Surprisingly, redshift and broadening of Raman vibrational modes were observed for agglomerated nanoparticles. Nonlinear relationships of Raman shift and full width at half maximum on the agglomeration of the Co3O4 nanoparticles have been experimentally determined. These results clearly indicate that proximity effects between nanoparticles in the agglomerate modify optical properties and Raman response. Nanoparticle agglomeration must then be taken into account for the understanding of nanoscale response in oxidic materials. Copyright © 2012 John Wiley & Sons, Ltd.
The effect of solution temperature and pH on corrosion performance and morphology of nanoceramic‐based conversion thin film
Authors: Mohammadloo H. Eivaz , Sarabi A. A. , Alvani A. A. Sabbagh , Salimi R. , Sameie H.
Published: March 2012

In the present study, a nanoceramic hexafluorozirconic acid was used as an eco‐friendly conversion coating, which is free of the conventional phosphate salts. The effect of practical parameters on morphology and corrosion resistance of the coating was studied. Anti‐corrosion behavior of the nanoceramic‐based conversion coating on cold rolled steel substrates was evaluated at different solution pH and temperatures, utilizing the electrochemical impedance spectroscopy and direct current polarization. Moreover, the morphology of thin films was studied using field emission scanning electron microscopy (FE‐SEM). The results revealed that the conversion thin films formed at a dipping temperature of 20 °C and pH 4.5 showed best anti‐corrosion performance. SEM images indicated that increasing solution temperature resulted in micro‐cracks creation and lack of consistency on the surface of the conversion coating. Moreover, the morphological structure changed with increasing pH value.
The influence of surface condition on the metal dusting behavior of cast and wrought chromia forming alloys
Authors: Hermse C. G. M. , Asteman H. , IJzerman R. M. , Jakobi D.
Published: March 2012

The current work investigated the impact of surface condition on the metal dusting behavior of chromia forming alloys. Five commercial alloys were included in the study, wrought 800H, 353MA, and cast G4859, G4852 Micro, and ET45 Micro, these alloys have a chromium and nickel content in the range of 20–35 wt% and 32–45 wt%, respectively. The wrought alloys were tested in a pickled state and the cast alloys with a machined surface, all the alloys were tested using a laboratory ground surface condition for comparison. The exposures were performed using a gas with a composition of 44 vol% CO, 52 vol% H2, 2 vol% CO2, and 2 vol% H2O at a temperature of 600 °C and a pressure of 5.5 bar. The samples were periodically characterized by measuring the mass loss, pit density, pit size, and pit depth. The results show that the pickled surfaces were sensitive toward metal dusting attack while the machined and the ground surfaces had better resistance. This shows that the surface pre‐treatment plays a crucial role.
Effects of the Zr and Mo contents on the electrochemical corrosion behavior of Ti–22Nb alloy
Authors: Yang S. , Zhang D. C. , Wei M. , Su H. X. , Wu W. , Lin J. G.
Published: March 2012

Ti–22Nb–xZr and Ti–22Nb–xMo (x = 0, 2, 4, 6, in atom percent) were prepared by an arc melting method. The alloys were solution‐treated at 1073 K for 1.8 ks followed by quenching them into ice water, and the electrochemical corrosion behavior in a 0.9% NaCl solution at 25 °C and neutral pH range of the solution‐treated alloys was evaluated by using electrochemical impedance spectroscopy, polarization curves and an equivalent circuit analysis. It was found that the microstructure of the solution‐treated Ti–22Nb alloy mainly contains β phase with small amount of α″ phase, and the addition of Zr or Mo to a Ti–22Nb alloy is efficient to stabilize the β phase. The resulting impedance parameters and passive current densities indicated that the corrosion resistance of the Ti–22Nb alloy was promoted significantly with the addition of Zr and Mo.
Corrosion and biocompatibility of PPy/PEG coating electrodeposited on Ti6Al7Nb alloy
Authors: Mîndroiu M. , Pîrvu C. , Cîmpean A. , Demetrescu I.
Published: March 2012

This work aims to improve the corrosion rate of Ti6Al7Nb alloy and to increase its biocompatibility at the same time, obtaining polymer composite films based on polypyrrole/polyethylene glycol (PPy/PEG). The elaboration method was electrodeposition. FT‐IR analysis was performed in order to emphasize the formation of the PPy‐PEG composite film by incorporating PEG into the polymer structure. The paper is focussed on PEG (400 molecular weight) effect on the corrosion in bioliquids (as tested electrochemical bioliquid was chosen Hank's balanced salt solution) and on the biocompatibility properties. The PPy film significantly improves the biocompatibility of the Ti6Al7Nb alloy. The PEG presence in the polymerization solution leads to more stable composite polymer films on the titanium alloy surface with a better corrosion resistance and a more hydrophilic behaviour comparing with the PPy film. The increase of cell viability and proliferation potential as compared to the PPy film is not important.
Clustering of Coated Droplets in Clay‐Filled Polymer Blends
Authors: Filippone Giovanni , Acierno Domenico
Published: March 2012

The selective positioning of clay platelets at the polymer/polymer interface in a blend with drop/matrix morphology has a contrasting effect: on the one hand, it promotes a refinement of the morphology during the intense flows which occur during melt compounding; on the other hand, it induces coarsening in the course of prolonged slow flows experienced during rheological analysis. Rather than to a usual coalescence process, the increase of the average sizes of the dispersed phase is primarily due to a clustering mechanism of clay‐coated droplets, which keep their individuality inside the clusters because of the elastic connotation of the layered interface.

magnified image
Ultrabroadband 8 × 8 Butler matrix designed with the use of multisection directional couplers and phase correction networks
Authors: Wincza Krzysztof , Gruszczynski Slawomir , Sachse Krzysztof , Kuta Stanislaw
Published: March 2012

An innovative approach that allows for realization of ultrabroadband 8 × 8 Butler matrices has been proposed. It is shown that such a matrix can be divided into two pairs of identical 4 × 4 submatrices, which appropriately connected constitute an ultrabroadband 8 × 8 Butler matrix. To achieve broadband operation in terms of amplitude multisection symmetrical coupled‐line directional couplers are used. Moreover, it has been shown that all the required broadband phase shifters can be realized with the use of tandem connections of two 3‐dB/90° directional couplers in conjunction with Schiffman C‐sections. To achieve that, four intentionally selected crossovers have been realized as tandem connections of two 3‐dB/90° coupled‐line directional couplers and appropriate Schiffman C‐sections have been added to the outer channels within each 4 × 4 submatrix. The proposed concept has been used for the design of an 8 × 8 Butler matrix operating in the frequency range 1.8–12 GHz and the measurements of the manufactured network are shown. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1375–1380, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26805
Internal digital video broadcasting‐handheld antenna with a low loss Z‐type hexaferrite for folder‐type mobile phones
Authors: Tang Yingming , Jia Lijun , Zhang Huaiwu , Liu Baoyuan
Published: March 2012

In this article, a new internal antenna with a Bi(Co)‐substituted Z‐type hexaferrite is presented for the digital video broadcasting‐handheld (DVB‐H) reception in folder‐type mobile phones.Using meandered current path on a low‐loss Z‐type hexaferrite substrate, the proposed antenna can be designed with a significantly small volume of 0.69 cm3 yet meeting the requirements of an antenna for the DVB‐H service. Approximately omnidirectional radiation characteristics are obtained. The measured return loss for the operating frequency over the DVB‐H band is better than 3:1 VSWR. In addition, the maximum radiation efficiency of the antenna is 63.7% in this band. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1380–1385, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26810
Flexible split‐ring resonator metamaterial structure at microwave frequencies
Authors: Ragi P. Menon. , Umadevi K. S. , Nees Paul. , Jose Jovia , Keerthy M. V. , Joseph V. P.
Published: March 2012

The authors present the fabrication method and resonant properties of a flexible split‐ring resonator (SRR) metamaterial structure at microwave frequencies. The structure is fabricated by chemical etching on a copper film glued on a thin low loss polymer substrate. The resonant properties using a single circular SRR between two monopole antennas were studied and compared with SRR fabricated on rigid circuit board. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1415–1416, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26814
Extending bandwidth of a CPW‐fed monopole antenna using circular arc structure
Authors: Chongcheawchamnan M. , Meelarpkit K. , Julrat S. , Phongchareonpanich C. , Krairiksh M.
Published: March 2012

A simple technique to extend bandwidth of a coplanar waveguide‐fed monopole antenna is proposed.This is achieved by bending a straight monopole to a circular arc. The technique is proven with several designs based on electromagnetic simulation where the technique applicability is experimentally demonstrated by a dual‐band monopole. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1412–1415, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26815
A high performance narrowband superconducting filter at Ku‐band
Authors: Li Qirong , Guo Xubo , Cao Bisong , Zhang Xiaoping , Wei Bin , Feng Cheng , Ying Zhijun , Zhang Guoyong , Jin Shichao
Published: March 2012

This letter presents the design, fabrication, and measurements of a high‐temperature superconducting (HTS) filter at 16 GHz with a 100‐MHz bandwidth. The main aspects of achieving high performance narrowband filter at such high frequency are analyzed and addressed. Simple rectangular resonators and end‐coupled structure are used in the design to achieve high quality factor (Q), weak coupling, and good parasitic response. The measurements of the seven‐pole HTS filter, without any tuning, exhibit a high performance. The insertion loss is less than 1.1 dB, equivalent of a resonator Q about 6100. The return loss is better than −15 dB, and the out‐of‐band rejection is over 70 dB up to 29.3 GHz. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1514–1516, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26816
Investigation on transmission characteristics of 40 Gb/s optical networks based on duobinary modulation
Authors: Yang Xusheng , Huang Xuguang , Xie Jinling , Zhu Jiahu , Li Guang
Published: March 2012

A novel method to generate optical duobinary (ODB) modulation format and its transmission characteristics in 40 Gb/s optical networks, compared with conventional modulation formats such as return‐to‐zero (RZ), non‐RZ, and carrier‐suppressed RZ in cascaded optical networks, is proposed and analyzed in this article. The transmission performances of these four modulation formats in terms of the capability of resisting the nonlinear effect of a fiber is investigated theoretically, for instance, self‐phase modulation, cross‐phase modulation, and four‐wave mixing. The chromatic dispersion tolerance of the four modulation formats mentioned above is also compared. The simulation results clearly show that the ODB modulation format has wider chromatic dispersion tolerance relative to the other formats. Moreover, after long‐haul transmission, the duobinary format signal has the lower bit‐error‐rate and higher receiving sensitivity compared with conventional format signals. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1355–1359, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26817