bluuebunny/crossref_metadata_2025_split huggingface dataset:
Self‐Assembled Aptamer‐Based Drug Carriers for Bispecific Cytotoxicity to Cancer Cells
Authors: Zhu Guizhi , Meng Ling , Ye Mao , Yang Liu , Sefah Kwame , O'Donoghue Meghan B. , Chen Yan , Xiong Xiangling , Huang Jin , Song Erqun , Tan Weihong 
Published: April 2012

AbstractMonovalent aptamers can deliver drugs to target cells by specific recognition. However, different cancer subtypes are distinguished by heterogeneous biomarkers and one single aptamer is unable to recognize all clinical samples from different patients with even the same type of cancers. To address heterogeneity among cancer subtypes for targeted drug delivery, as a model, we developed a drug carrier with a broader recognition range of cancer subtypes. This carrier, sgc8c‐sgd5a (SD), was self‐assembled from two modified monovalent aptamers. It showed bispecific recognition abilities to target cells in cell mixtures; thus broadening the recognition capabilities of its parent aptamers. The self‐assembly of SD simultaneously formed multiple drug loading sites for the anticancer drug doxorubicin (Dox). The Dox‐loaded SD (SD–Dox) also showed bispecific abilities for target cell binding and drug delivery. Most importantly, SD–Dox induced bispecific cytotoxicity in target cells in cell mixtures. Therefore, by broadening the otherwise limited recognition capabilities of monovalent aptamers, bispecific aptamer‐based drug carriers would facilitate aptamer applications for clinically heterogeneous cancer subtypes that respond to the same cancer therapy.
Unsymmetric Platinum(II) Bis(aryleneethynylene) Complexes as Photosensitizers for Dye‐Sensitized Solar Cells
Authors: Dai Feng‐Rong , Chen Yung‐Chung , Lai Lai‐Fan , Wu Wen‐Jun , Cui Chao‐Hua , Tan Gui‐Ping , Wang Xing‐Zhu , Lin Jiann‐T'suen , Tian He , Wong Wai‐Yeung 
Published: April 2012

AbstractFour new unsymmetric platinum(II) bis(aryleneethynylene) derivatives have been designed and synthesized, which showed good light‐harvesting capabilities for application as photosensitizers in dye‐sensitized solar cells (DSSCs). The absorption, electrochemical, time‐dependent density functional theory (TD‐DFT), impedance spectroscopic, and photovoltaic properties of these platinum(II)‐based sensitizers have been fully characterized. The optical and TD‐DFT studies show that the incorporation of a strongly electron‐donating group significantly enhances the absorption abilities of the complexes. The maximum absorption wavelength of these four organometallic dyes can be tuned by various structural modifications of the triphenylamine and/or thiophene electron donor, improving the light absorption range up to 650 nm. The photovoltaic performance of these dyes as photosensitizers in mesoporous TiO2 solar cells was investigated, and a power conversion efficiency as high as 1.57 % was achieved, with an open‐circuit voltage of 0.59 V, short‐circuit current density of 3.63 mA cm−2, and fill factor of 0.73 under simulated AM 1.5G solar illumination.
Amide‐Directed Tandem CC/CN Bond Formation through CH Activation
Authors: Zhu Chen , Wang Rui , Falck John R. 
Published: April 2012

AbstractThe transformation of CH bonds into other chemical bonds is of great significance in synthetic chemistry. CH bond‐activation processes provide a straightforward and atom‐economic strategy for the construction of complex structures; as such, they have attracted widespread interest over the past decade. As a prevalent directing group in the field of CH activation, the amide group not only offers excellent regiodirecting ability, but is also a potential CN bond precursor. As a consequence, a variety of nitrogen‐containing heterocycles have been obtained by using these reactions. This Focus Review addresses the recent research into the amide‐directed tandem CC/CN bond‐formation process through CH activation. The large body of research in this field over the past three years has established it as one of the most‐important topics in organic chemistry.
Application of a probabilistic neural network in radial‐velocity curve analysis of the spectroscopic binary stars HD 152218, HD 143511, HD 27149, and ER Vul
Authors: Pirkhedri A. , Ghaderi K. , Javadi H.H.S. , Karimizadeh K. 
Published: April 2012

AbstractWe use an Artificial Neural Network (ANN) to derive the orbital parameters of spectroscopic binary stars. Using measured radial velocity data of four double‐lined spectroscopic binary systems HD 152218, HD 143511, HD 27149, and ER Vul, we find corresponding orbital and spectroscopic elements. Our numerical results are in good agreement with those obtained by others using more traditional methods (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Transport of angular momentum and chemical species by anisotropic mixing in stellar radiative interiors
Authors: Kitchatinov L.L. , Brandenburg A. 
Published: April 2012

AbstractSmall levels of turbulence can be present in stellar radiative interiors due to, e.g., the instability of rotational shear. In this paper we estimate turbulent transport coefficients for stably stratified rotating stellar radiation zones. Stable stratification induces strong anisotropy with a very small ratio of radial‐to‐horizontal turbulence intensities. Angular momentum is transported mainly due to the correlation between azimuthal and radial turbulent motions induced by the Coriolis force. This non‐diffusive transport known as the Λ‐effect has outward direction in radius and is much more efficient compared to the effect of radial eddy viscosity. Chemical species are transported by small radial diffusion only. This result is confirmed using direct numerical simulations combined with the test‐scalar method. As a consequence of the non‐diffusive transport of angular momentum, the estimated characteristic time of rotational coupling (≲100 Myr) between radiative core and convective envelope in young solar‐type stars is much shorter compared to the time‐scale of Lithium depletion (∼1 Gyr) (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Space astronomy for the mid‐21st century: Robotically maintained space telescopes
Authors: Schartel N. 
Published: April 2012

AbstractThe historical development of ground based astronomical telescopes leads us to expect that space‐based astronomical telescopes will need tobe operational for many decades. The exchange of scientific instruments in space will be a prerequisite for the long lasting scientific success of such missions. Operationally, the possibility to repair or replace key spacecraft components in space will be mandatory. We argue that these requirements can be fulfilled with robotic missions and see the development of the required engineering as the main challenge. Ground based operations, scientifically and technically, will require a low operational budget of the running costs. These can be achieved through enhanced autonomy of the spacecraft and mission independent concepts for the support of the software. This concept can be applied to areas where the mirror capabilities do not constrain the lifetime of the mission (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Thermomagnetic and magnetorotational instabilities of thin Keplerian discs in poloidal magnetic fields
Authors: Shtemler Y.M. , Liverts E. , Mond M. 
Published: April 2012

AbstractStability of thin hot Keplerian discs is investigated asymptotically in small disc's aspect ratio, ε. The study is carried out in the local approximation for short vertical waves in the disc‐thickness scale. Besides the radial rotation shear and the vertical magnetic field, the background configuration is characterized by a vertically near‐constant temperature profile with a small vertical gradient. The temperature‐gradient term in Ohm's law, which characterizes the thermomagnetic transport is found to be of the order of ε. The effect of the thermomagnetic transport slightly modifies the conventional magnetorotational instability (MRI), while a new thermomagnetic instability (TMI) emerges in regions of the wavenumber space where MRI is absent. Explicit solutions are obtained for a wide range of values of plasma beta, β, and thermomagnetic transport coefficient, λ. In particular, it is shown for λ ≪ 1 that the MRI dominates in weak magnetic fields, β ≫ 1, while the TMI is exhibited in strong magnetic fields, β ∼ 1, also with the growth rate of the order of inverse rotation period (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Career situation of female astronomers in Germany
Authors: Fohlmeister J. , Helling Ch. 
Published: April 2012

AbstractWe survey the job situation of women in astronomy in Germany and of German women abroad and review indicators for their career development. Our sample includes women astronomers from all academic levels from doctoral students to professors, as well as female astronomers who have left the field. We find that networking and human support are among the most important factors for success. Experience shows that students should carefully choose their supervisor and collect practical knowledge abroad. We reflect the private situation of female German astronomers and find that prejudices are abundant, and are perceived as discriminating. We identify reasons why women are more likely than men to quit astronomy after they obtain their PhD degree. We give recommendations to young students on what to pay attention to in order tobe on the successful path in astronomy (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Linear stability analysis of the Hall magnetorotational instability in a spherical domain
Authors: Kondić T. , Rüdiger G. , Arlt R. 
Published: April 2012

AbstractWe investigate the stability of the Hall‐MHD system and determine its importance for neutron stars at their birth, when they still consist of differentially rotating plasma permeated by extremely strong magnetic fields. We solve the linearised HallMHD equations in a spherical shell threaded by a homogeneous magnetic field. With the fluid/flow coupling and the Hall effect included, the magnetorotational instability and the Hall effect are both acting together. Results differ for magnetic fields aligned with the rotation axis and anti‐parallel magnetic fields. For a positive alignment of the magnetic field the instability grows on a rotational time‐scale for any sufficiently large magnetic Reynolds number. Even the magnetic fields which are stable against the MRI due to the magnetic diffusion are now susceptible to the shear‐Hall instability. In contrast, the negative alignment places strong restrictions on the growth and the magnitude of the fields, hindering the effectiveness of the Hall‐MRI. While non‐axisymmetric modes of the MRI can be suppressed by strong enough rotation, there is no such restriction when the Hall effect is present. The implications for the magnitude and the topology of the magnetic field of a young neutron star may be significant (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Role‐Induced Bias in Court: An Experimental Analysis
Authors: Engel Christoph , Glöckner Andreas 
Published: April 2012

AbstractCriminal procedure is organized as a tournament with predefined roles. We show that assuming the role of a defense counsel or a prosecutor leads to role‐induced bias even if participants are asked to predict a court ruling after they have ceased to act in that role and if they expect a substantial financial incentive for being accurate. The bias is not removed either if participants are instructed to predict the court ruling in preparation of plea bargaining. In line with parallel constraint satisfaction models for legal decision making, findings indicate that role‐induced bias is driven by coherence effects, that is, systematic information distortions in support of the favored option. This is mainly achieved by downplaying the importance of conflicting evidence. These distortions seem to stabilize interpretations, and people do not correct for this bias. Implications for legal procedure are briefly discussed. Copyright © 2012 John Wiley & Sons, Ltd.
Dosimetry evaluation of a cylindrical waveguide chamber for unrestrained small rodents at 1.9 GHz
Authors: Wasoontarajaroen Siriwat , Thansandote Artnarong , Gajda Gregory B. , Lemay Eric P. , McNamee James P. , Bellier Pascale V. 
Published: April 2012

AbstractAn exposure system, consisting of four identical cylindrical waveguide chambers, was developed for studying the effects of radiofrequency (RF) energy on laboratory mice at a frequency of 1.9 GHz. The chamber was characterized for RF dose rate as a function of animal body mass and dose rate variations due to animal movement in the cage. Dose rates were quantified in terms of whole‐body average (WBA) specific absorption rate (SAR), brain average (BA) SAR and peak spatial‐average (PSA) SAR using measurement and computational methods. Measurements were conducted on mouse cadavers in a multitude of possible postures and positions to evaluate the variations of WBA‐SAR and its upper and lower bounds, while computations utilizing the finite‐difference time‐domain method together with a heterogeneous mouse model were performed to determine variations in BA‐SAR and the ratio of PSA‐SAR to WBA‐SAR. Measured WBA‐SAR variations were found to be within the ranges of 9–23.5 W/kg and 5.2–13.8 W/kg per 1 W incident power for 20 and 40 g mice, respectively. Computed BA‐SAR variations were within the ranges of 3.2–10.1 W/kg and 3.3–9.2 W/kg per 1 W incident power for 25 and 30 g mouse models, respectively. Ratios of PSA‐SAR to WBA‐SAR, averaged over 0.5 mg and 5 mg tissue volumes, were observed to be within the ranges of 6–15 and 4–10, respectively. Bioelectromagnetics 33:575–584, 2012. © 2012 Wiley Periodicals, Inc.
Extremely low‐frequency magnetic fields modulate nitric oxide signaling in rat brain
Authors: Cho Sung In , Nam Yun Sung , Chu Li Ying , Lee Jong Hyuk , Bang Joon Seok , Kim Hye Ryoun , Kim Hyoung‐Chun , Lee Yu Jeung , Kim Hyeong‐Dong , Sul Jung Duk , Kim Daejin , Chung Yoon Hee , Jeong Ji Hoon 
Published: April 2012

AbstractOur previous study has shown that an extremely low‐frequency magnetic field (ELF‐MF) induces nitric oxide (NO) synthesis by Ca2+‐dependent NO synthase (NOS) in rat brain. The present study was designed to confirm that ELF‐MF affects neuronal NOS (nNOS) in several brain regions and to investigate the correlation between NO and nNOS activation. The exposure of rats to a 2 mT, 60 Hz ELF‐MF for 5 days resulted in increases of NO levels in parallel with cGMP elevations in the cerebral cortex, striatum, and hippocampus. Cresyl violet staining and electron microscopic evaluation revealed that there were no significant differences in the morphology and number of neurons in the cerebral cortex, striatum, and hippocampus. Differently, the numbers of nNOS‐immunoreactive (IR) neurons were significantly increased in those cerebral areas in ELF‐MF‐exposed rats. These data suggest that the increase in NO could be due to the increased expression and activation of nNOS in cells. Based on NO signaling in physiological and pathological states, ELF‐MF created by electric power systems may induce various physiological changes in modern life. Bioelectromagnetics 33:568–574, 2012. © 2012 Wiley Periodicals, Inc.
Induced electric field and current density patterns in bone fractures
Authors: Greenebaum Ben 
Published: April 2012

AbstractWe have used the low frequency solver of the computer program SEMCAD‐X to model the induced electric field and current density patterns in simple models of a fractured femur embedded off‐center in cylindrical muscle tissue; a 1 cm fracture gap is filled with callus. The model is exposed to a 1 kHz, 1 mT sinusoidal magnetic field. The frequency chosen is typical of the major Fourier components of many waveforms used to stimulate fracture healing using pulsed magnetic fields; the intensity is also a typical level. Models include fractures perpendicular to the bone and at an angle from the perpendicular, each exposed to a field applied parallel to the bone or parallel to either of the two axes perpendicular to it. We find that all directions of applied magnetic fields produce essentially parallel induced electric fields and current densities through the plane of the callus, but that a magnetic field applied parallel to the bone induces considerably higher fields and currents than the same strength field applied in either perpendicular direction. Because investigations of pulsed‐field devices, including modeling of induced fields and currents, peaked more than a decade ago, this is the first application to our knowledge of the current capabilities of computer modeling systems to biological systems at low frequencies. Bioelectromagnetics 33:585–593, 2012. © 2012 Wiley Periodicals, Inc.
Poor‐to‐moderate agreement between self and proxy interviews of mobile phone use
Authors: Hutter Hans‐Peter , Ehrenhöfer Lisa , Freuis Edith , Hartl Patrik , Kundi Michael 
Published: April 2012

AbstractIn epidemiological studies, cases cannot always be interviewed due to them being too ill or already deceased. Under these circumstances, proxy interviews are often conducted; however, the veridicality of information about mobile phone use gained by proxy interviews has been doubted. The issue is undecided due to the lack of empirical data. We conducted a study of 119 heterosexual couples. Both partners answered two questionnaires about mobile phone use, one about their own use and one about their partner's use. Overall agreement assessed using Cohen's kappa, Passing and Bablok regression, and concordance coefficients between self and proxy data was poor to moderate (e.g., concordance coefficients of 0.55 for duration of use). The only item with good agreement was whether or not a prepaid phone was used (Cohen's kappa 0.78 and 0.63 for male and female estimates, respectively), and to a lesser degree, the onset of mobile phone use (concordance coefficients of 0.66 and 0.61). Poorest agreement was obtained for the side of the head the mobile phone was held during calls (kappa coefficients of 0.20 and 0.24 for female and male estimates, respectively). We conclude that the assessment of mobile phone use by proxy data cannot be relied on except for information about onset of mobile phone use, use of prepaid or contract phones, and, to a lesser degree, duration of daily use. Agreement concerning the important information about side of the head the mobile phone is held during calls was poorest and only slightly better than chance. Bioelectromagnetics 33:561–567, 2012. © 2012 Wiley Periodicals, Inc.
Caring for the Children of Imprisoned Mothers: Exploring the Role of Fathers
Authors: Flynn Catherine 
Published: April 2012

Women are the most rapidly growing group of prisoners in Western jurisdictions, with the majority of them mothers. Research conducted over the past 40 years has concentrated on describing, but not evaluating, the circumstances, including the care arrangements, of their dependent children. Whilst fathers have played a small but significant role in this care, they are largely absent from discourse. This paper discusses research findings about the role of fathers in providing care to children while their mothers are in prison. This is part of a wider study which examined the impact of maternal incarceration on 20 young people in Victoria, Australia. In the current study, findings indicate that although fathers were the largest group providing care for these young people, participants were mostly unsatisfied with these arrangements. The current study considers children's and mothers' perceptions of the quality of that care and implications for mother‐child relationships. Copyright © 2012 John Wiley & Sons, Ltd.‘Part of a wider study which examined the impact of maternal incarceration’Key Practitioner Messages

Increasing numbers of children and young people are experiencing the imprisonment of their mothers.
Children of incarcerated mothers are more likely to experience the loss of their primary carer and subsequent instability.
Fathers are providing care to a sizeable group of children while their mothers are in prison.
We currently know little about the care provided by fathers: how it is arranged, its quality or the needs of carers and children.
Reductive Coupling of Aldehydes by H2S in Aqueous Solutions, a CC Bond Forming Reaction of Prebiotic Interest
Authors: Kajjout Mohammed , Hebting Yanek , Albrecht Pierre , Adam Pierre 
Published: April 2012

AbstractWe report here a novel reductive coupling reaction of conjugated, non‐ or poorly enolizable aldehydes induced by H2S and operative in aqueous solutions under prebiotically relevant conditions. This reaction leads from retinal to β‐carotene, and from benzylic aldehydes to the corresponding diarylethylenes. This novel reaction also opens a new potentially prebiotic pathway leading from glyoxylic acid to various compounds that are involved in the reductive tricarboxylic acid cycle. This CC bond forming reaction of prebiotic interest might have been operative, notably, in the sulfide‐rich environments of hydrothermal vents, which have been postulated as possible sites for the first steps of organic chemical evolution.
Concomitant Induction of Heme Oxygenase‐1 Attenuates the Cytotoxicity of Arsenic Species from Lumbricus Extract in Human Liver HepG2 Cells
Authors: Qi Hongyi , Chen Baowei , Le X. Chris , Rong Jianhui 
Published: April 2012

AbstractHeme oxygenase‐1 (HO‐1) is an inducible antioxidant enzyme that degrades heme to three products, biliverdin, carbon monoxide (CO), and iron ion. The present study was originally designed to characterize the HO‐1 induction by Lumbricus extract as a potential cytoprotective mechanism. Through bioactivity‐guided fractionation, with human HepG2 cells as the cellular detector, surprisingly, we found that arsenic was enriched in the active fractions isolated from Lumbricus extract. Arsenic speciation was further carried out by liquid chromatography with inductively coupled plasma mass spectrometry (LC/ICP‐MS). Our results showed that Lumbricus extract contained two major arsenic species, arsenite (AsIII; 53.7%) and arsenate (AsV; 34.2%), and six minor arsenic species. Commercial sodium arsenite (NaAsO2) was used to verify the effects of Lumbricus extract on HO‐1 expression and related intracellular signaling pathways. Both p38 MAP kinase and NF‐E2‐related factor 2 (Nrf2) pathways were found to modulate HO‐1 induction by Lumbricus extract and NaAsO2. The cytotoxicity of arsenite was augmented by p38 MAP kinase inhibitor SB202190 and HO‐1 inhibitor tin protoporphyrin IX (SnPP), whereas p38 MAP kinase inhibitor SB202190 also inhibited HO‐1 induction by NaAsO2. These results suggest that arsenic‐containing compounds are responsible for HO‐1 induction by Lumbricus extract. Although the exact role of toxic arsenic compounds in the treatment of oxidative injury remains unclear, concomitant HO‐1 induction may be a key mechanism to antagonize the cytotoxicity of arsenic compounds in human cells.
Two New Norlignans and a New Lignanamide from Peperomia tetraphylla
Authors: Li Yun‐Zhi , Tong Ai‐Ping , Huang Jing 
Published: April 2012

AbstractTwo new cyclobutane‐type norlignans, methyl rel‐(1R,2S,3S)‐2‐(7‐methoxy‐1,3‐benzodioxol‐5‐yl)‐3‐(2,4,5‐trimethoxyphenyl)cyclobutanecarboxylate (1), and methyl rel‐(1R,2R,3S)‐2‐(7‐methoxy‐1,3‐benzodioxol‐5‐yl)‐3‐(2,4,5‐trimethoxyphenyl)cyclobutanecarboxylate (2), and a new lignanamide, 3‐hydroxy‐N‐[2‐(4‐hydroxyphenyl)ethyl]‐α‐[4‐(2‐{N‐[2‐(4‐hydroxyphenyl)ethyl]carbamoyl}ethenyl)‐3‐methoxyphenoxy]‐4‐methoxycinnamamide 4,8″‐ether (3), along with five known amides, 4–8, were obtained from the whole plant of Peperomia tetraphylla. Their structures were elucidated mainly by the analysis of NMR and MS data. The new compounds 1–3 and the known compound 4 were tested for their cytotoxic activities against the HepG2 (human hepatocarcinoma), A549 (human lung cancer), and HeLa (human cervical cancer) cell lines. Compound 4 showed significant cytotoxicity against HepG2 cell lines with an IC50 value of 9.4±1.0 μM.