bluuebunny/crossref_metadata_2025 huggingface dataset:
Convergence of human brain mapping tools: Neuronavigated TMS Parameters and fMRI activity in the hand motor area
Authors: Sarfeld Anna‐Sophia , Diekhoff Svenja , Wang Ling E. , Liuzzi Gianpiero , Uludağ Kamil , Eickhoff Simon B. , Fink Gereon R. , Grefkes Christian
Published: April 2011

Functional magnetic resonance imaging (fMRI) and transcranial magnetic stimulation (TMS) are well‐established tools for investigating the human motor system in‐vivo. We here studied the relationship between movement‐related fMRI signal changes in the primary motor cortex (M1) and electrophysiological properties of the hand motor area assessed with neuronavigated TMS in 17 healthy subjects. The voxel showing the highest task‐related BOLD response in the left hand motor area during right hand movements was identified for each individual subject. This fMRI peak voxel in M1 served as spatial target for coil positioning during neuronavigated TMS. We performed correlation analyses between TMS parameters, BOLD signal estimates and effective connectivity parameters of M1 assessed with dynamic causal modeling (DCM). The results showed a negative correlation between the movement‐related BOLD signal in left M1 and resting as well as active motor threshold (MT) obtained for left M1. The DCM analysis revealed that higher excitability of left M1 was associated with a stronger coupling between left supplementary motor area (SMA) and M1. Furthermore, BOLD activity in left M1 correlated with ipsilateral silent period (ISP), i.e. the stronger the task‐related BOLD response in left M1, the higher interhemispheric inhibition effects targeting right M1. DCM analyses revealed a positive correlation between the coupling of left SMA with left M1 and the duration of ISP. The data show that TMS parameters assessed for the hand area of M1 do not only reflect the intrinsic properties at the stimulation site but also interactions with remote areas in the human motor system. Hum Brain Mapp, 2011. © 2011 Wiley‐Liss, Inc.
Contextual interaction between novelty and reward processing within the mesolimbic system
Authors: Bunzeck Nico , Doeller Christian F. , Dolan Ray J. , Duzel Emrah
Published: April 2011

Medial temporal lobe (MTL) dependent long‐term memory for novel events is modulated by a circuitry that also responds to reward and includes the ventral striatum, dopaminergic midbrain, and medial orbitofrontal cortex (mOFC). This common neural network may reflect a functional link between novelty and reward whereby novelty motivates exploration in the search for rewards; a link also termed novelty “exploration bonus.” We used fMRI in a scene encoding paradigm to investigate the interaction between novelty and reward with a focus on neural signals akin to an exploration bonus. As expected, reward related long‐term memory for the scenes (after 24 hours) strongly correlated with activity of MTL, ventral striatum, and substantia nigra/ventral tegmental area (SN/VTA). Furthermore, the hippocampus showed a main effect of novelty, the striatum showed a main effect of reward, and the mOFC signalled both novelty and reward. An interaction between novelty and reward akin to an exploration bonus was found in the hippocampus. These data suggest that MTL novelty signals are interpreted in terms of their reward‐predicting properties in the mOFC, which biases striatal reward responses. The striatum together with the SN/VTA then regulates MTL‐dependent long‐term memory formation and contextual exploration bonus signals in the hippocampus. Hum Brain Mapp, 2011. © 2011 Wiley‐Liss, Inc.
Hepatic stellate cells: Partners in crime for liver metastases?
Authors: Kang Ningling , Gores Gregory J. , Shah Vijay H.
Published: April 2011

Hepatic stellate cells (HSCs) were recently postulated as a component of the prometastatic liver microenvironment, because they can transdifferentiate into highly proliferative and motile myofibroblasts that are implicated in the desmoplastic reaction and metastatic growth. This review focuses on bidirectional interactions between tumor cells and HSCs in the liver microenvironment and discusses mechanisms whereby tumor-derived factors activate HSCs, and in turn, activated HSCs promote metastatic growth. Bidirectional interactions between tumors and HSCs may function as an “amplification loop” to further enhance metastatic growth in the liver. The activation of HSCs is a complex process regulated by multiple factors such as transforming growth factor-β and platelet-derived growth factor signaling pathways, which may present as therapeutic targets in the prevention and treatment of liver metastases.

Conclusion:

HSCs may present a new therapeutic target in the treatment of liver metastases. Targeting HSCs and/or myofibroblasts with transforming growth factor-β or platelet-derived growth factor antagonists in coordination with chemotherapy, radiotherapy, or surgery may prove to be effective at reducing liver metastases and increasing the survival benefit of patients by targeting both tumor cells and the tumor microenvironment. (Hepatology 2011;)
Central (ICV) leptin injection increases bone formation, bone mineral density, muscle mass, serum IGF-1, and the expression of osteogenic genes in leptin-deficient ob/ob mice
Authors: Bartell Shoshana M , Rayalam Srujana , Ambati Suresh , Gaddam Dhanunjaya R , Hartzell Diane L , Hamrick Mark , She Jin-Xiong , Della-Fera Mary Anne , Baile Clifton A
Published: April 2011

Both central and peripheral leptin administrations reduce body weight, food intake, and adiposity in ob/ob mice. In this study we compared effects of intracerebroventricular (ICV) and subcutaneous (SC) administration of leptin on bone metabolism in the appendicular and axial skeleton and adipose tissue gene expression and determined the effects of ICV leptin on bone marrow gene expression in ob/ob mice. In experiment 1, leptin (1.5 or 0.38 µg/d) or control was continuously injected ICV for 12 days. Gene expression analysis of femoral bone marrow stromal cells showed that expression of genes associated with osteogenesis was increased after ICV injection, whereas those associated with osteoclastogenesis, adipogenesis, and adipocyte lipid storage were decreased. In experiment 2, leptin was injected continuously ICV (0.0 or 1.5 µg/d) or SC (0.0 or 10 µg/d) for 12 days. In both experiments, regardless of mode of administration, leptin decreased body weight, food intake, and body fat and increased muscle mass, bone mineral density, bone mineral content, bone area, marrow adipocyte number, and mineral apposition rate. Serum insulin was decreased, whereas serum osteocalcin, insulin-like growth factor 1, osteoprotegerin, pyridinoline, and receptor activator of nuclear factor κB ligand concentrations were increased. In experiment 2, expression of genes in adipose tissue associated with apoptosis, lipid mobilization, insulin sensitivity, and thermogenesis was increased, whereas expression of genes associated with cell differentiation and maturation was decreased regardless of mode of administration. Thus ICV injection of leptin promotes expression of pro-osteogenic factors in bone marrow, leading to enhanced bone formation in ob/ob mice. © 2011 American Society for Bone and Mineral Research
Bone mineral accrual from 8 to 30 years of age: An estimation of peak bone mass
Authors: Baxter-Jones Adam DG , Faulkner Robert A , Forwood Mark R , Mirwald Robert L , Bailey Donald A
Published: April 2011

Bone area (BA) and bone mineral content (BMC) were measured from childhood to young adulthood at the total body (TB), lumbar spine (LS), total hip (TH), and femoral neck (FN). BA and BMC values were expressed as a percentage of young-adult values to determine if and when values reached a plateau. Data were aligned on biological ages [years from peak height velocity (PHV)] to control for maturity. TB BA increased significantly from −4 to +4 years from PHV, with TB BMC reaching a plateau, on average, 2 years later at +6 years from PHV (equates to 18 and 20 years of age in girls and boys, respectively). LS BA increased significantly from −4 years from PHV to +3 years from PHV, whereas LS BMC increased until +4 from PHV. FN BA increased between −4 and +1 years from PHV, with FN BMC reaching a plateau, on average, 1 year later at +2 years from PHV. In the circumpubertal years (−2 to +2 years from PHV): 39% of the young-adult BMC was accrued at the TB in both males and females; 43% and 46% was accrued in males and females at the LS and TH, respectively; 33% (males and females) was accrued at the FN. In summary, we provide strong evidence that BA plateaus 1 to 2 years earlier than BMC. Depending on the skeletal site, peak bone mass occurs by the end of the second or early in the third decade of life. The data substantiate the importance of the circumpubertal years for accruing bone mineral. © 2011 American Society for Bone and Mineral Research
Gray‐scale and color Doppler sonographic appearances of nonsubungual soft‐tissue glomus tumors
Authors: Park Hee‐Jin , Jeon Yong Hwan , Kim Sam Soo , Lee Sung‐Moon , Kim Wan‐Tae , Park Noh‐Hyuck , Park Sung‐Il , Hong Hyun‐Pyo , Rho Myung‐Ho
Published: April 2011

Background.

To evaluate the sonographic findings of soft‐tissue nonsubungual glomus tumors.

Methods.

The sonographic appearances of nine histologically proven soft‐tissue glomus tumors of nonsubungual location in nine patients (mean age, 49 years; M:F = 7:2) were reviewed retrospectively. Doppler examination and surgical excision were performed in all cases.

Results.

The mean size of the lesions was 1 cm. The margins of the lesions were relatively well‐circumscribed in eight of nine patients (89%) with an ovoid shape in seven of nine patients (78%). The vascularity was moderate to rich in all cases, with an arterial flow pattern but no arteriovenous shunt patterns. The “vascular stalk sign” was noted in six cases (67%).

Conclusions.

Nonsubungual glomus tumors are rare soft‐tissue tumors with abundant vascularity and arterial flow pattern. © 2011 Wiley Periodicals, Inc. J Clin Ultrasound, 2011;
New conditions for synthesis of (±)‐2‐monosubstituted and (±)‐2,2‐disubstituted 2,3‐dihydro‐4(1H)‐quinazolinones from 2‐nitro‐ and 2‐aminobenzamide
Authors: Bunce Richard A. , Nammalwar Baskar
Published: April 2011

An efficient synthesis of (±)‐2‐monosubstituted and (±)‐2,2‐disubstituted 2,3‐dihydro‐4(1H)‐quinazolinones has been developed using a dissolving metal reduction‐condensative cyclization strategy. Treatment of 2‐nitrobenzamide and an aldehyde or ketone with iron powder in refluxing acetic acid affords high yields of the title compounds. More complex ring systems are available by incorporating additional reactive functionality γ to the carbonyl of the aldehyde or ketone substrate. The scope and limitations of the process along with optimized procedural details are presented. The same target molecules are also accessible by reaction of 2‐aminobenzamide with aldehydes and ketones in refluxing acetic acid. J. Heterocyclic Chem., (2011).
Eastward shift of the Pacific/North American pattern on an interdecadal time scale and an associated synoptic eddy feedback
Authors: Lee Yun‐Young , Kug Jong‐Seong , Lim Gyu‐Ho , Watanabe Masahiro
Published: April 2011

In this study, we investigate the interdecadal changes in the Pacific/North American (PNA) pattern during the winter season (November–February) that accompanies the global‐scale climate shift in the late 1970s. In the Empirical Orthogonal Function (EOF) analysis, the PNA pattern shows three distinctive features during the period of 1983–2002 in contrast with that of the previous decades (1959–1977): the extension of the central North Pacific cell into the Gulf of Alaska, the eastward shift of the action centre of the Canadian cell, and weakening of the North America cell. Pacific/North American structural changes are closely related to the southeastward shift of the storm track that causes the vigorous synoptic eddy feedback region to move farther east. Eddy activity feeds the cyclonic flow at the eastern part of conventional central North Pacific cell, following the pattern change of storm track. Copyright © 2011 Royal Meteorological Society
Influence of the West Spitsbergen Current on the local climate
Authors: Walczowski Waldemar , Piechura Jan
Published: April 2011

Oceanographic observations of the Nordic Seas show significant interannual variability of the inflowing Atlantic Water properties and currents structure. Variations of the oceanic heat advected northward with the Atlantic Water influence climate. The aim of the study was examination, how changes of the West Spitsbergen Current properties and pathways influence the local climate conditions in the Fram Strait region. Results from observations carried in the Nordic Seas by the Institute of Oceanology Polish Academy of Sciences in summers 2000–2007 were compared with time series of air temperature in Spitsbergen and sea ice conditions north of Spitsbergen. We conclude that the heat advected with the West Spitsbergen Current shapes local conditions mostly during the winter. The highest correlations occur between the temperature of Atlantic Water and air temperature as well as the sea ice cover in the following winter. Copyright © 2011 Royal Meteorological Society
Home range, habitat use, and activity patterns of free‐roaming domestic cats
Authors: Horn Jeff A. , Mateus‐Pinilla Nohra , Warner Richard E. , Heske Edward J.
Published: April 2011

We used radio‐telemetry and collar‐mounted activity sensors to compare home range size, habitat use, and activity patterns of owned and unowned free‐roaming cats on the outskirts of Champaign‐Urbana, Illinois, USA. Owned cats (3 M, 8 F) had smaller home ranges than unowned cats (6 M, 10 F), but we failed to detect consistent differences in home range size between the sexes or among seasons. Home ranges of unowned cats included more grassland and urban area than predicted based on availability in all seasons, and farmsteads were selected in fall and winter. Within home ranges, unowned cats shifted their use of habitats among seasons in ways that likely reflected prey availability, predation risk, and environmental stress, whereas habitat use within home ranges by owned cats did not differ from random. Unowned cats were more nocturnal and showed higher overall levels of activity than owned cats. Space use and behavioral differences between owned and unowned cats supported the hypothesis that the care a cat owner provides influences the impact a cat has on its environment, information that is important for making decisions on controlling cat populations. © 2011 The Wildlife Society.
Comparing detection dog and livetrapping surveys for a cryptic rodent
Authors: Duggan Jennifer M. , Heske Edward J. , Schooley Robert L. , Hurt Aimee , Whitelaw Alice
Published: April 2011

We compared the effectiveness and cost of distribution surveys using livetrapping to those using detection dog‐handler teams for a cryptic rodent (Franklin's ground squirrel [Poliocitellus franklinii]). We livetrapped at 62 sites in Illinois, Indiana, Iowa, Missouri, and Wisconsin for Franklin's ground squirrels in 2007–2009 and surveyed 40 of those sites using detection dogs in 2009. Independent surveys of a site by 2 dog‐handler teams took <1 hr and yielded detection rates comparable to 2 daily livetrapping surveys (detection rate = 83–84%). However, false presences are a potential problem when detection dogs are trained to scent of a species that leaves little visual sign to confirm its presence. Surveys by 2 dog‐handler teams cost >2 daily livetrapping surveys conducted by 2 technicians but more and larger sites can be surveyed by dog‐handler teams in a shorter time. For surveys covering large spatial scales or when time is a limiting factor, number of false presences, and study costs can be reduced by employing a 2‐stage survey protocol in which livetrapping is conducted only at sites where detection dog surveys indicate presence. We conclude a 2‐stage strategy could be used effectively in large‐scale surveys for a variety of rare and cryptic species. © 2011 The Wildlife Society.
The different kinetic and mechanistic behaviors of molybdenum and tungsten in the reduction of tris(benzene‐1,2‐dithiolato)Mo(VI) and W(VI) complexes by ascorbic acid in aqueous media
Authors: Pérez‐Pla Francisco , Llopis Elisa , Piles María
Published: April 2011

The mono‐electronic reduction of tris(benzene‐1,2‐dithiolato)Mo(VI) and W(VI) complexes (ML3: M = Mo, W; L = S2C6H2−4, S2C6H3CH2−3) to their anionic forms ML−3 by L(+)‐ascorbic acid (H2A) has been studied in tetrahydrofurane (THF):water and THF:methanol by means of diode‐array, stopped‐flow, and mass spectrometry–electrospray ionization (MS‐ESI) spectroscopy. The kinetic study in methanol demonstrates that the reaction is first order in each reactant, the electron transfer being rate limiting. This fact was assessed by the absence of a primary saline effect and by the correlation observed between the activation free enthalpy (ΔG≠) and the reduction potentials measured by cyclic voltamperometry. In aqueous media, Mo(VI)‐tris(dithiolenes) also reduce to their Mo(V) anionic forms. The reaction obeys the rate law − d[ML3]/dt = (kS+kA[H2A]T)[ML3] (M = Mo), in agreement with a parallel kinetic scheme involving the reduction of complexes by ascorbic acid (kA) and by interaction with the solvent (kS). Unexpectedly, the W(VI) complexes were not reduced by excess hydrogen ascorbate in the presence of water. These compounds underwent an extremely rapid autoreduction, which initially yielded an oxo W(VI)‐dithiolene and [W(S2C6H4)3]−, as assessed by the MS‐ESI spectra. This observation suggests that tungsten tris(dithiolenes) are capable of coordinating water efficiently, undergoing further reduction after ligand displacement. © 2011 Wiley Peiodicals, Inc. Int J Chem Kinet 43: 279–291, 2011
A Novel Photopolymerization Initiating System Based on an Iridium Complex Photocatalyst
Authors: Lalevée Jacques , Blanchard Nicolas , Tehfe Mohamad‐Ali , Peter Mathieu , Morlet‐Savary Fabrice , Fouassier Jean Pierre
Published: April 2011

The use of a photocatalyst (tris(2‐phenylpyridine)iridium [Ir(ppy)3]) being able to generate both radicals and cations to initiate free radical polymerization and ring opening polymerization is presented. Remarkably, under soft irradiations (fluorescence bulb, sunlight), excellent cationic polymerization profiles and final conversions are obtained. The involved mechanisms are investigated by ESR experiments.

magnified image
Clinical and urodynamic effect of methylphenidate for the treatment of giggle incontinence (enuresis risoria)
Authors: Chang Joo‐Hyun , Lee Kwang‐Yeom , Kim Tae‐Beom , Yoon Sang‐Jin , Lee Tack , Kim Khae‐Hawn
Published: April 2011

Aims

We retrospectively investigated the efficacy of methylphenidate (MPH) in giggle incontinence (GI), and the relationship between GI and urodynamic parameters.

Methods

Nine (n = 9) female GI patients underwent 1 year of treatment with 5 mg MPH. Three questionnaires, voiding diaries, and UDS were conducted before and after treatment. The severity of GI was classified into mild, moderate, and severe. Clinical success was characterized as: full response, response, partial response, and non‐response.

Results

The mean age of all patients was 16.2 ± 2.3 years. Five patients had mild, one had moderate, and three had severe grade incontinent. All patients reported complete cessation of wetting after MPH treatment. The mean duration of asymptomatic period was 7 ± 3.2 months. There were no statistically significant score changes in all three questionnaires: Urgency Perception Scale (UPS), Overactive Bladder Symptom Score (OABSS) and Primary Overactive Symptom Questionnaire (POSQ), and voiding diaries (P > 0.05). In UDS, there were no statistically significant altered parameters, except maximum urethral closure pressure (MUCP) and maximum urethral pressure (MUP). After treatment, the mean MUCP was increased from 52.2 ± 6.8 to 73.0 ± 5.4 cmH2O (P < 0.05), and the mean MUP was increased from 48.6 ± 7.3 to 70.2 ± 5.0 cmH2O (P < 0.05).

Conclusions

MPH can be a viable option for the primary treatment of GI, and it may be related to increasing urethral closure pressure. It was not possible to establish if a relationship between GI and detrusor overactivity exists. Neurourol. Urodynam. 30:1338–1342, 2011. © 2010 Wiley‐Liss, Inc.
Nephrin expression in adult rodent central nervous system and its interaction with glutamate receptors
Authors: Li Min , Armelloni Silvia , Ikehata Masami , Corbelli Alessandro , Pesaresi Marzia , Calvaresi Novella , Giardino Laura , Mattinzoli Deborah , Nisticò Francesca , Andreoni Serena , Puliti Aldamaria , Ravazzolo Roberto , Forloni Gianluigi , Messa Piergiorgio , Rastaldi Maria Pia
Published: April 2011

Nephrin is an immunoglobulin‐like adhesion molecule first discovered as a major component of the podocyte slit diaphragm, where its integrity is essential to the function of the glomerular filtration barrier. Outside the kidney, nephrin has been shown in other restricted locations, most notably in the central nervous system (CNS) of embryonic and newborn rodents. With the aim of better characterizing nephrin expression and its role in the CNS of adult rodents, we studied its expression pattern and possible binding partners in CNS tissues and cultured neuronal cells and compared these data to those obtained in control renal tissues and podocyte cell cultures. Our results show that, besides a number of locations already found in embryos and newborns, endogenous nephrin in adult rodent CNS extends to the pons and corpus callosum and is expressed by granule cells and Purkinje cells of the cerebellum, with a characteristic alternating expression pattern. In primary neuronal cells we find nephrin expression close to synaptic proteins and demonstrate that nephrin co‐immunoprecipitates with Fyn kinase, glutamate receptors and the scaffolding molecule PSD95, an assembly that is reminiscent of those made by synaptic adhesion molecules. This role seems to be confirmed by our findings of impaired maturation and reduced glutamate exocytosis occurring in Neuro2A cells upon nephrin silencing. Of note, we disclose that the very same nephrin interactions occur in renal glomeruli and cultured podocytes, supporting our hypothesis that podocytes organize and use similar molecular intercellular signalling modules to those used by neuronal cells. Copyright © 2011 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Health‐related quality of life (HRQoL): The impact of medical and demographic variables upon pediatric recipients of hematopoietic stem cell transplantation
Authors: Brice Lisa , Weiss Rebecca , Wei Ying , Satwani Prakash , Bhatia Monica , George Diane , Garvin James , Morris Erin , Harrison Lauren , Cairo Mitchell S. , Sands Stephen A.
Published: April 2011

Background

The trajectory of Heath‐Related Quality of Life (HRQoL) in pediatric recipients who have undergone hematopoietic stem cell transplantation (HSCT), as well as the demographic and medical factors that predict HRQoL, has lagged behind the adult research.

Methods

A prospective longitudinal study of HRQoL in pediatric HSCT recipients was conducted with 95 patients at the Columbia University Medical Center between 2002 and 2009. Both children and parents completed the PedsQL 4.0 prior to HSCT and at days 100, 180, and 365‐post‐HSCT.

Results

The majority of patients and their parents reported linear improvements in HRQoL in the first year post‐transplant; however, a portion of patients were in the at‐risk group at each time point. Latent growth modeling was utilized to examine demographic and medical factors that predicted initial HRQoL and its trajectory. Older age at transplant significant predicted lowered HRQoL at baseline for self‐ and parent‐report. Female gender significantly impacted lowered self‐reported physical HRQoL over time. Ethnicity was a significant predictor of HRQoL at baseline and over time for self‐ and parent‐report, with African‐American children reporting the highest HRQoL; whereas, the worst decline in psychosocial HRQoL was often reported by parents and children of Asian descent.

Conclusion

This research identifies the significant impact of ethnicity upon HRQoL following pediatric HSCT. It is likely that an individual's pre‐morbid experiences and expectations, particularly with regard to culture, behaviors, and values, influence the parent and child's perceptions and expectations of the HSCT process. Pediatr Blood Cancer 2011; 57: 1179–1185. © 2011 Wiley Periodicals, Inc.
Synthesis of all‐conjugated poly(3‐hexylthiophene)‐block‐ poly(3‐(4′‐(3″,7″‐dimethyloctyloxy)‐3′‐pyridinyl)thiophene) and its blend for photovoltaic applications
Authors: Lai Yi‐Cang , Ohshimizu Kaoru , Takahashi Ayumi , Hsu Jung‐Ching , Higashihara Tomoya , Ueda Mitsuru , Chen Wen‐Chang
Published: April 2011

New all‐conjugated block copolythiophene, poly(3‐hexylthiophene)‐block‐poly(3‐(4′‐(3″,7″‐dimethyloctyloxy)‐3′‐pyridinyl)thiophene) (P3HT‐b‐P3PyT) was successfully prepared by Grignard metathesis polymerization. The supramolecular interaction between [6,6]‐phenyl‐C61‐butyric acid methyl ester (PCBM) and P3PyT was proposed to control the aggregated size of PCBM and long‐term thermal stability of the photovoltaic cell, as evidenced by differential scanning calorimetry (DSC), transmission electron microscopy (TEM), and optical microscopy. The effect of different solvents on the electronic and optoelectronic properties was studied, including chloroform (CL), dichlorobenzene (DCB), and mixed solvent of CL/DCB. The optimized bulk heterojunction solar cell devices using the P3HT‐b‐P3PyT/PCBM blend showed a power conversion efficiency of 2.12%, comparable to that of P3HT/PCBM device despite the fact that former had a lower crystallinity or absorption coefficient. Furthermore, P3HT‐b‐P3PyT could be also used as a surfactant to enhance the long‐term thermal stability of P3HT/PCBM‐based solar cells by limiting the aggregated size of PCBM. This study represents a new supramolecular approach to design all‐conjugated block copolymers for high‐performance photovoltaic devices. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011.
Adsorption of Sn on the Ge(111)‐(3 × 3) surface studied by ab initio density functional theory
Authors: Özkaya Sibel , Çakmak Mehmet , Alkan Bora
Published: April 2011

We present detailed ab initio density functional calculations of equilibrium atomic geometry, electronic states, and chemical bonding for the adsorption of the elemental Sn atoms on the Ge(111)‐(3 × 3) surface. Three different possible models: (i) IDA model (inequivalent‐two‐down Sn atoms), (ii) 1U2D model (one‐up Sn atom, two‐equivalent‐down Sn atoms), and (iii) 2U1D model (two‐up Sn atoms, one‐down Sn atom) have been considered. From these three models, it has been found that the IDA and 1U2D models are energetically favorable than the third model. The energy difference between the IDA and 1U2D model is negligibly small. For the IDA model, the height difference between two down atoms in IDA model is significant. A total of three surface states originating from the Sn adatoms is determined. The results are in good agreement with the recent high‐resolution photoemission and scanning tunneling microscopy experiments.
Evaluation of GaN by photoluminescence measurement
Authors: Reshchikov Michael A.
Published: April 2011

Comparison of the room‐temperature photoluminescence (PL) spectra from a high‐quality freestanding GaN template and an average‐quality GaN layer on sapphire substrate shows that the width of the exciton band in the former may be twice larger than that in the latter. The surprising fact can be explained by a wide depletion region and large diffusion length of photogenerated carriers in high‐quality GaN templates. Photogenerated electrons and holes in this material recombine at larger distance from the surface, and the exciton emission from this depth experiences stronger absorption that causes distortion of the near‐bandedge PL and its broadening. We also explain why the intensity of the exciton emission may be low and the defect‐related PL may dominate in the room‐temperature PL spectrum of high‐quality samples. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Surface properties of AlxGa1‐xN/GaN heterostructures treated by fluorine plasma: an XPS study
Authors: Huang Sen , Chen Hongwei , Chen Kevin J.
Published: April 2011

The variations in surface potential and the Schottky barrier height ΦB in fluorine‐plasma‐treated AlxGa1‐xN/GaN heterotructures are systematically studied by x‐ray photoelectron spectroscopy (XPS), giving insights into the mechanisms underlying the strong threshold voltage shift in AlxGa1‐xN/GaN HEMTs by the F plasma treatment technology. It is found that the treatment resulted in a fluorinated surface containing masses of AlF3, with the surface potential of Al0.25Ga0.75N/GaN heterostructure increased by ∼0.38 eV during the first 60 seconds of the treatment. Annealing at 400 °C in N2 ambient for 10 minutes does not affect the surface potential, but results in quick reduction of AlF3, consistent with the relative poor thermal stability of AlF3 reported in literature. ΦB between Ni and F‐plasma‐treated Al0.25Ga0.75N surface was extrapolated from the shift in Ga 2p3/2 core‐level and exhibits a small increase of 0.20 eV. The enhanced ΦB is much smaller than the positive shift in Vth observed from HEMTs fabricated with the same treatment conditions, suggesting that the primary factor responsible for the conversion from depletion‐mode to enhancement‐mode AlxGa1‐xN/GaN by F plasma treatment is not the surface modifications, but rather the negative fixed charges carried by F ions in AlxGa1‐xN/GaN heterostructures. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Semi‐polar InN(10$ \bar 1 $3) dominant growth on GaAs(110) substrate by mixing hydrogen in carrier gas
Authors: Cho H. C. , Suematsu M. , Murakami H. , Kumagai Y. , Tob R. , Koukitu A.
Published: April 2011

The growth of semi‐polar InN(10$ \bar 1 $3) on a GaAs(110) substrate by metal organic vapor phase epitaxy (MOVPE) was investigated. It was confirmed that the semi‐polar InN(10$ \bar 1 $3) plane was dominantly grown by mixing 0.4% hydrogen in nitrogen carrier gas, whereas a ‐plane InN was mixed without hydrogen gas. An ω‐mode X‐ray rocking curve of the InN(10$ \bar 1 $3) plane revealed that the InN(10$ \bar 1 $3) crystals were tilted approximately 1.1∼1.4° in the direction of the GaAs[111] due to the structural difference between InN(10$ \bar 1 $3) and GaAs(110). Although the as‐grown InN was twin crystal, however, the integrated intensity of smaller peak was less than 1% in related to that of the other peak. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Terminalia chebula Extract Acts as a Potential NF‐κB Inhibitor in Human Lymphoblastic T Cells
Authors: Das Nando Dulal , Jung Kyoung Hwa , Park Ji Hyun , Mondol Md. Abdul Mojid , Shin Hee Jae , Lee Hyi‐Seung , Park Kyoung Sun , Choi Mi Ran , Kim Kyung Suk , Kim Moo Sung , Lee Sang Rin , Chai Young Gyu
Published: April 2011

Terminalia chebula (TC) is native to southern Asia to southwestern China and is used in traditional medicine for the treatment of human ailments including malignant tumors and diabetes. This plant also has antibacterial and immunomodulatory properties. Nuclear factor kappa‐light chain‐enhancer of activated B cells (NF‐κB) is responsible for the expression of numerous genes involved in cell survival, proliferation, angiogenesis, inflammation, invasion and metastasis, among other processes. This study aims to assess the NF‐κB inhibitory effect of TC extract in human lymphoblastic T (Jurkat) cells. The effects of TC extract were investigated using the FRET‐based Gene Blazer technique in transfected Jurkat‐NF‐κB‐RE‐bla cells. The concentration of TC extract required for NF‐κB inhibition was determined by a cell proliferation assay. Treatment with TC extract (50 μg/mL) inhibited NF‐κB activity and protected against IκBα degradation and strongly suppressed IκBα phosphorylation in Jurkat‐NF‐κB‐RE‐bla cells. This treatment might be crucial for inhibiting NF‐κB translocation and activation. In addition, the TC extract downregulated certain NF‐κB regulated genes, including IL‐8 and MCP‐1, in Jurkat‐NF‐κB‐RE‐bla cells. Moreover, gallic acid was identified from the TC extract demonstrating its ability to inhibit NF‐κB activity in Jurkat‐NF‐κB‐RE‐bla cells. Further studies to identify the role of gallic acid in NF‐κB inhibition may uncover the crucial antiinflammatory and antitumor properties of the TC extract. Copyright © 2011 John Wiley & Sons, Ltd.
Analysis as‐randomized and the problem of non‐adherence: An example from the veterans affairs randomized trial of coronary artery bypass surgery
Authors: Peduzzi Peter , Wittes Janet , Detre Katherine , Holford Theodore
Published: April 2011

In most randomized clinical trials not all patients adhere to the therapy to which they were randomly assigned. Instead, they may receive the therapy assigned to another treatment group, or a therapy different from any prescribed in the protocol. When non‐adherence occurs, problems occur with the analysis comparing the treatments under study. Rigorous statistical principles require attributing outcome events to the original random treatment assignment (‘intent‐to‐treat’ analysis). Using data from the Veterans Administration Cooperative Study of Coronary Artery Bypass Surgery, we report the intent‐to‐treat analysis and apply four other methods of analysis for analysing non‐adherers: 1. exclude non‐adherers from analysis; 2. transfer them to the alternative treatment group at the time of randomization; 3. censor them at the time of treatment change, and 4. transfer them to the alternative treatment group at the time of treatment change. Inherent problems and biases of these four other methods are discussed.
Methods for assessing difference between groups in change when initial measurement is subject to intra‐individual variation
Authors: Chambless Lloyd E. , Roeback John R.
Published: April 2011

Statistical analysis of difference between groups in change for some variable, adjusting for initial value, is complicated by the presence of intra‐individual variation in that variable. We estimate here the asymptotic bais that results from calculating the adjusted between‐group difference by ordinary least squares (OLS) from observed data. We also present explicit formulae that use the OLS estimates, the difference between treatment groups in mean initial values, and a measure of the intra‐individual variation to compute a corrected estimator and its variance. Alternatively, we can use OLS on transformed data to obtain unbiased estimates, in which we replace initial observed values by conditional Stein estimates of true values. We illustrate the results with data from an observational study and a clinical trial.
Design effects for binary regression models fitted to dependent data
Authors: Neuhaus John M. , Segal Mark R.
Published: April 2011

Dependent data, such as arise with cluster sampling, typically yield variances of parameter estimates which are larger than would be provided by a simple random sample of the same size. This variance inflation factor is called the design effect of the estimator. Design effects have been derived for cluster sampling designs using simple estimators such as means and proportions, and also for linear regression coefficient estimators. In this paper, we show that a method to derive design effects for linear regression estimators extends to generalized linear models for binary responses. In particular, some simple expressions for design effects in the linear regression model provide accurate approximations for binary regression models such as those based on the logistic, probit and complementary log—log links. We corroborate our findings with two examples and some simulation studies.
Modeling of Mechanical Characteristics in Hot Deformation of 4130 Steel
Authors: Sajadifar S.V. , ketabchi M. , Nourani M.
Published: April 2011

In this investigation, hot compression tests were performed at 900 °C − 1100 °C and strain rate of 0.001 − 0.1 s−1 to study hot deformation behavior and flow stress model of 4130 steel. Based on the classical stress–dislocation relations and the kinematics of the dynamic recrystallization, the flow stress constitutive equations of the work hardening‐dynamical recovery period and dynamical recrystallization period were established for 4130 steel, respectively. The validity of the model was demonstrated by comparing the experimental data with the numerical results. The agreement of this comparison is quite reasonable.
A model and scoring system to predict outcome of intrauterine pregnancies of uncertain viability
Authors: Bottomley C. , Van Belle V. , Pexsters A. , Papageorghiou A. T. , Mukri F. , Kirk E. , Van Huffel S. , Timmerman D. , Bourne T.
Published: April 2011

Objectives

To define the incidence and outcome of intrauterine pregnancy of uncertain viability (PUV) and to develop and assess the performance of a model and a scoring system to predict ongoing viability.

Methods

Of 1881 consecutive women undergoing transvaginal ultrasonography, a cohort of 493 women with an empty gestational sac < 20 mm in mean diameter, gestational sac < 25 mm in mean diameter and containing yolk sac only or an embryonic pole < 6 mm in maximum length and without visible heart activity were followed until the end of the first trimester. Women with multiple pregnancies or who underwent termination of pregnancy were excluded. Outcome measures were pregnancy viability at initial 7–14‐day follow‐up and first‐trimester viability at 11–14 weeks. The data were split randomly into two sets (two‐thirds and one‐third, respectively) in order to first develop and then test a mathematical model and a ‘simple’ model in the prediction of viability at each outcome point, based on maternal demographics, ultrasound features and symptoms. The performance of each system was assessed by receiver–operating characteristics (ROC) curve analysis and calibration plots on a test dataset.

Results

The incidence of PUV in this population was 29.2% (549/1881). Of the 493 pregnancies with initial (7–14 days) follow‐up available, 307 (62.3%) were viable at this time and of the 444 pregnancies with follow‐up at the end of the first trimester, 225 (50.7%) were still viable. Initial (7–14‐day) viability was predicted by the model with an area under the ROC curve (AUC) of 0.837 (95% CI, 0.791–0.884) in the training dataset and 0.821 (95% CI, 0.756–0.885) in the test dataset. First‐trimester (11–14‐week) viability was predicted by the model with an AUC of 0.788 (95% CI, 0.734–0.842) in the training dataset and 0.774 (95% CI, 0.701–0.848) in the test dataset. The scoring system performed slightly worse than did the model, but had the advantage of being easily applicable.

Conclusions

When early pregnancy viability cannot be established immediately with ultrasound, use of either a logistic regression model or a scoring system allows an individualized prediction of first‐trimester outcome. Copyright © 2011 ISUOG. Published by John Wiley & Sons, Ltd.
Early screening for pre‐eclampsia and intrauterine growth restriction
Authors: Harrington Kevin
Published: April 2011

Themed Virtual Issue

Key papers in Ultrasound in Obstetrics & Gynecology on: Copyright © 2011 ISUOG. Published by John Wiley & Sons, Ltd.
Infinite-dimensional attractors for parabolic equations with p-Laplacian in heterogeneous medium
Authors: Efendiev Messoud A. , Ôtani Mitsuharu
Published: April 2011

In this paper we give a detailed study of the global attractors for parabolic equations governed by the
p
-Laplacian in a heterogeneous medium. Not only the existence but also the infinite dimensionality of the global attractors is presented by showing that their
ε
-Kolmogorov entropy behaves as a polynomial of the variable

1/ \varepsilon

as
ε
tends to zero, which is not observed for non-degenerate parabolic equations. The upper and lower bounds for the Kolmogorov
ε
-entropy of infinite-dimensional attractors are also obtained.
Mid-Holocene coastal hydrology and salinity changes in the east Taihu area of the lower Yangtze wetlands, China
Authors: Zong Yongqiang , Innes James B. , Wang Zhanghua , Chen Zhongyuan
Published: April 2011

During the mid-Holocene the eastern Taihu area, on China's Yangtze delta plain, was populated by advanced late Neolithic cultures supported by intensive domesticated rice cultivation. This agricultural system collapsed around 4200 cal yr BP, with severe population decline, the end of the Liangzhu culture, and about half a millennium of very low-scale human activity in the area before the re-establishment of agricultural production. Microfossil analyses from six sedimentary sequences, supported by AMS 14C dating, has allowed reconstruction of mid-Holocene hydrological conditions and salinity changes which would have had a major influence on agricultural viability and cultural history in the coastal wetlands. These data, allied to existing stratigraphic and sea-level records, show that chenier ridges that developed after ca. 7000 cal yr BP in the east of the area sheltered it from marine inundation and although still connected to the sea through tidal creeks, low-salinity conditions persisted throughout the Neolithic period. There is no evidence that marine flooding caused the collapse of Liangzhu culture. Marine influence was stable and evolved slowly. Social and cultural causes may also have been important, but if environmental change triggered the collapse of Neolithic agricultural society here, other natural forces must be sought to explain this event.
An Insular Brooch-Fragment from Norway
Authors: Bourke Cormac , Fanning Thomas , Whitfield Niamh
Published: April 2011

A silver-gilt ornament of Insular origin from a Viking age burial in Norway is here identified for the first time as the pin-head of a ring brooch of pseudo-penannular form. The decoration and typology of the pin-head are discussed in relation to Insular metalwork, and its iconography is considered in the context of Early Christian art. The pin-head and an associated ringed pin are dated to the eighth or ninth century.
A Nineteenth-Century Grubenhaus on Bucklebury Common, Berkshire
Authors: Myres J. N. L. , Dixon Philip H.
Published: April 2011

The Museum of English Rural Life at Reading University was for some years interested in a hut on Bucklebury Common, Berkshire, which was occupied as a workshop by the Lailey family who used it for the manufacture of wooden bowls which found a ready market. When the last of these craftsmen bowlturners died without male heirs in 1958 and the workshop was likely to be demolished, the Museum took steps both to secure one of the primitive pole-lathes used by the Laileys in their craft, which is now displayed in the Museum, and also to make a photographic and measured record of the hut itself and its contents. From this record, which the Museum has kindly allowed us to use in preparing this article, it is evident that the hut itself had been a structure of considerable architectural interest. Part of it had a deeply sunken floor which had carried the pole-lathes, and was similar in size and shape to an Anglo- Saxon Grubenhaus of the pagan period. Although the walls and roof were clearly of later date, they could well have taken the place of much earlier predecessors. The purpose of this article is thus to draw attention to the continued use into the present century not only of the bowltumer's primitive craft at Bucklebury but of its housing in a hut which probably began as an Anglo-Saxon Grubenhaus. As such its structure and furnishing may throw light on features that have sometimes puzzled students of excavated Anglo-Saxon Grubenhäuser elsewhere.
An Aristocratic Tomb of the Roman Period from Mtskheta, Georgia
Authors: Apakidze A. , Nikolaishvili V.
Published: April 2011

In 1985, a stone-built tomb of the second or third centuries AD was found in the Samtavro cemetery on the outskirts of Mtskheta, the ancient capital of the Caucasian kingdom of Iberia. Its rich contents included a Mesopotamian cylinder- and an Achaemenid pyramidal stamp-seal, three sardonyx vessels, several pieces of silver plate bearing Greek and Parthian inscriptions, Roman coins and bronze vessels, and distinctive jewellery inlaid with carnelian and turquoise. The Society of Antiquaries is pleased to offer the hospitality of its pages to its Georgian colleagues
The Buildings of St Mary's Abbey, York and Their Destruction
Authors: Norton Christopher
Published: April 2011

St Mary's Abbey, York was one of the richest Benedictine monasteries in the country and its buildings reflected its wealth and status. The quality of its architectural remains is of the highest order, and the collection of medieval sculpture from the site is outstanding. Indeed, the set of life-size column-figures brought to light in 1829 must count as one of the most exciting discoveries ever made in the field of the history of sculpture in this country. Nor is the later history of the site any less interesting. At the Dissolution it became the seat of the King's Council in the North and acquired the name of King's Manor, which part of the complex retains to this day. The principal monastic buildings came down within a few years, and their demolition can be followed in considerable detail, as we shall see; but the centuries of Crown ownership prevented the division of the property until the nineteenth century, and it remains one of the best-preserved urban (albeit extra-mural) monastic precincts in Britain.
A Probable Mercian Royal Mausoleum at Winchcombe, Gloucestershire
Authors: Bassett S. R.
Published: April 2011

Winchcombe, a leading Mercian centre, was a royal burial-place and, later, the cult-centre of the alleged royal child-martyr Cynhelm. The antiquary Leland refers to an ancient chapel of St Pancras at Winchcombe lying between its two major medieval churches, both of which are arguably of Anglo-Saxon origin. The chapel is very probably one described in 1320 as having a cellarium, which may have been a crypt. The paper suggests that this chapel was, until the late tenth or early eleventh century, the free-standing mausoleum of Cynhelm and perhaps also of his father, King Coenwulf of Mercia, and discusses its precise whereabouts.
Romano-British Settlement and Industry on the Wetlands of the Severn Estuary
Authors: Allen J. R. L. , Fulford M. G.
Published: April 2011

A review of the post-glacial geology and geomorphology of the Severn Estuary provides a context for the description and evaluation of eight sites on the margins of the Severn upstream of the Rivers Avon and Wye where Romano-British occupation debris has been recovered. This evidence provides further confirmation of the extent of the reclamation and settlement of the wetlands of the Severn during the Roman period. In addition, all sites produced clear evidence of ironmaking, employing Forest of Dean ore, and one site produced indications of glassworking. In conjunction with a comparative study of the pottery assemblages from riverside and inland sites, the role of the river as a trade route is reviewed.
Early Muslim Trading Settlements on the East African Coast: New Evidence from Shanga
Authors: Horton M. C.
Published: April 2011

Much archaeological and historical research has recently been devoted to the study of the early Swahili communities inhabiting the East African coast during the late first millenniuma.d.The practice of Islam can be shown to date back to perhaps the beginning of the ninth century from when the first mosques have been excavated. The economic importance of East Africa for the Indian Ocean and Mediterranean world is apparent from the wealth of imports and exports found in a large number of these coastal sites. African trading systems brought to medieval society high-value commodities ranging from gold, rock crystal and ivory, to slaves and timber. The items were carried across large distances sea by traders following the seasonal monsoon system around the coasts and across the Indian Ocean. is argued that the trading settlements were African in culture and origin, but then attracted Muslims who were responsible for occasional local converts from a very early period in the history of Islam.