bluuebunny/crossref_metadata_2025 huggingface dataset:
Combination of Virtual Touch Tissue Imaging and Virtual Touch Tissue Quantification for Differential Diagnosis of Breast Lesions
Authors: Teke Memik , Göya Cemil , Teke Fatma , Uslukaya Ömer , Hamidi Cihad , Çetinçakmak Mehmet Guli , Hattapoğlu Salih , Alan Bircan , Tekbaş Güven
Published: June 2015

Objectives

Breast cancer is the second leading cause of death from cancer in women, and early detection is the key to successful treatment. Unfortunately, even with technological advances, the specificity of imaging modalities is still low. Therefore, we evaluated the value of a newly developed noninvasive technique, acoustic radiation force impulse imaging, for differentiating benign versus malignant breast lesions.

Methods

We prospectively examined 141 breast lesions in 122 patients. All lesions were classified according to the American College of Radiology Breast Imaging Reporting and Data System (BI‐RADS) for mammography, BI‐RADS for sonography, and Virtual Touch tissue imaging (VTI; Siemens Medical Solutions, Mountain View, CA) pattern. Internal and marginal shear wave velocity (SWV) values for the lesions were noted. The sensitivity, specificity, accuracy, and positive and negative predictive values for VTI and Virtual Touch tissue quantification (VTQ; Siemens Medical Solutions) were calculated.

Results

The marginal SWV values were statistically higher in malignant lesions (mean ± SD, 5.41 ± 1.37 m/s) than benign lesions (2.91 ± 0.88 m/s; P < .001). When the SWV cutoff level was set at 4.07 m/s, and the higher of the internal and marginal values was adopted, the combination of VTI and VTQ showed 95.1% sensitivity, 99.0% specificity, and 97.8% accuracy.

Conclusions

Breast Imaging Reporting and Data System category 4 lesions are the main focus of research for early detection of breast cancer. Unfortunately, BI‐RADS category 4 assessment covers a wide range of likelihood of malignancy (2%–95%). This wide range reflects the necessity for a more specific imaging modality. The combination of VTI and VTQ could increase the diagnostic performance of conventional sonography.
Contrast Ultrasound Imaging Does Not Affect Heat Shock Protein 70 Expression in Cholesterol‐Fed Rabbit Aorta
Authors: Smith Brendon W. , Simpson Douglas G. , Miller Rita J. , Erdman John W. , O'Brien William D.
Published: June 2015

Objectives

Diagnostic ultrasound imaging is enhanced by the use of circulating microbubble contrast agents (UCAs), but the interactions between ultrasound, UCAs, and vascular tissue are not fully understood. We hypothesized that ultrasound with a UCA would stress the vascular tissue and increase levels of heat shock protein 70 (Hsp70), a cellular stress protein.

Methods

Male New Zealand White rabbits (n = 32) were fed a standard chow diet (n = 4) or a 1% cholesterol, 10% fat, and 0.11% magnesium diet (n = 28). At 21 days, 24 rabbits on the cholesterol diet were either exposed to ultrasound (3.2‐MHz f/3 transducer; 2.1 MPa; mechanical index, 1.17; 10 Hz pulse repetition frequency; 1.6 microseconds pulse duration; 2 minutes exposure duration at 4 sites along the aorta) with the UCA Definity (1× concentration, 1 mL/min; Lantheus Medical Imaging, North Billerica, MA) or sham exposed with a saline vehicle injection (n = 12 per group). Four rabbits on the cholesterol diet and 4 on the chow diet served as cage controls and were not exposed to ultrasound or restrained for blood sample collection. Animals were euthanized 24 hours after exposure, and aortas were quickly isolated and frozen in liquid nitrogen. Aorta lysates from the area of ultrasound exposure were analyzed for Hsp70 level by Western blot. Blood plasma was analyzed for cholesterol, Hsp70, and von Willebrand factor, a marker of endothelial function.

Results

Plasma total cholesterol levels increased to an average of 705 mg/dL. Ultrasound did not affect plasma von Willebrand factor, plasma Hsp70, or aorta Hsp70. Restraint increased Hsp70 (P < .001, analysis of variance).

Conclusions

Restraint, but not ultrasound with the UCA or cholesterol feeding, significantly increased Hsp70.
Quantification of factors impacting seawater and calcite δ18O during Heinrich Stadials 1 and 4
Authors: Bagniewski Witold , Meissner Katrin J. , Menviel Laurie , Brennan Catherine E.
Published: June 2015

We perform idealized experiments of a Heinrich Stadial using an oxygen‐isotope‐enabled Earth System Climate Model. Our results compare relatively well with the planktic and benthic δ18O records of Heinrich Stadials 1 and 4. We find that changes in surface
can be equally attributed to the “temperature effect” due to fractionation during calcification; the “circulation and climate effect” due to changes in circulation, precipitation, and evaporation; and the “meltwater effect” due to the addition and subsequent advection of depleted fresh water from continental ice sheets. In contrast, the meltwater effect and circulation and climate effect have only a small impact on benthic
during the cessation of the Atlantic Meridional Overturning Circulation (AMOC). Significant temperature changes simulated in both the deep Atlantic and Pacific Oceans substantially influence benthic
during that time. During the AMOC recovery, however, anomalously low
surface waters are advected to the deep Atlantic, thus generating a large (∼0.5‰)
decrease in the deep North Atlantic. This is in contrast to a hypothesis that links such depletion seen in Atlantic sediment cores during the last glacial stadials to deepwater formation caused by brine rejection and sea ice formation.
Deglacial subarctic Pacific surface water hydrography and nutrient dynamics and links to North Atlantic climate variability and atmospheric CO2
Authors: Maier E. , Méheust M. , Abelmann A. , Gersonde R. , Chapligin B. , Ren J. , Stein R. , Meyer H. , Tiedemann R.
Published: June 2015

The glacial‐to‐Holocene evolution of subarctic Pacific surface water stratification and silicic acid (Si) dynamics is investigated based on new combined diatom oxygen (δ18Odiat) and silicon (δ30Sidiat) isotope records, along with new biogenic opal, subsurface foraminiferal δ18O, alkenone‐based sea surface temperature, sea ice, diatom, and core logging data from the NE Pacific. Our results suggest that δ18Odiat values are primarily influenced by changes in freshwater discharge from the Cordilleran Ice Sheet (CIS), while corresponding δ30Sidiat are primarily influenced by changes in Si supply to surface waters. Our data indicate enhanced glacial to mid Heinrich Stadial 1 (HS1) NE Pacific surface water stratification, generally limiting the Si supply to surface waters. However, we suggest that an increase in Si supply during early HS1, when surface waters were still stratified, is linked to increased North Pacific Intermediate Water formation. The coincidence between fresh surface waters during HS1 and enhanced ice‐rafted debris sedimentation in the North Atlantic indicates a close link between CIS and Laurentide Ice Sheet dynamics and a dominant atmospheric control on CIS deglaciation. The Bølling/Allerød (B/A) is characterized by destratification in the subarctic Pacific and an increased supply of saline, Si‐rich waters to surface waters. This change toward increased convection occurred prior to the Bølling warming and is likely triggered by a switch to sea ice‐free conditions during late HS1. Our results furthermore indicate a decreased efficiency of the biological pump during late HS1 and the B/A (possibly also the Younger Dryas), suggesting that the subarctic Pacific has then been a source region of atmospheric CO2.
Modern solar maximum forced late twentieth century Greenland cooling
Authors: Kobashi T. , Box J. E. , Vinther B. M. , Goto‐Azuma K. , Blunier T. , White J. W. C. , Nakaegawa T. , Andresen C. S.
Published: June 2015

The abrupt Northern Hemispheric warming at the end of the twentieth century has been attributed to an enhanced greenhouse effect. Yet Greenland and surrounding subpolar North Atlantic remained anomalously cold in 1970s to early 1990s. Here we reconstructed robust Greenland temperature records (North Greenland Ice Core Project and Greenland Ice Sheet Project 2) over the past 2100 years using argon and nitrogen isotopes in air trapped within ice cores and show that this cold anomaly was part of a recursive pattern of antiphase Greenland temperature responses to solar variability with a possible multidecadal lag. We hypothesize that high solar activity during the modern solar maximum (approximately 1950s–1980s) resulted in a cooling over Greenland and surrounding subpolar North Atlantic through the slowdown of Atlantic Meridional Overturning Circulation with atmospheric feedback processes.
Substorm evolution of auroral structures
Authors: Partamies N. , Juusola L. , Whiter D. , Kauristie K.
Published: June 2015

Auroral arcs are often associated with magnetically quiet time and substorm growth phases. We have studied the evolution of auroral structures during global and local magnetic activity to investigate the occurrence rate of auroral arcs during different levels of magnetic activity. The ground‐magnetic and auroral conditions are described by the magnetometer and auroral camera data from five Magnetometers — Ionospheric radars — All‐sky cameras Large Experiment stations in Finnish and Swedish Lapland. We identified substorm growth, expansion, and recovery phases from the local electrojet index (IL) in 1996–2007 and analyzed the auroral structures during the different phases. Auroral structures were also analyzed during different global magnetic activity levels, as described by the planetary Kp index. The distribution of auroral structures for all substorm phases and Kp levels is of similar shape. About one third of all detected structures are auroral arcs. This suggests that auroral arcs occur in all conditions as the main element of the aurora. The most arc‐dominated substorm phases occur in the premidnight sector, while the least arc‐dominated substorm phases take place in the dawn sector. Arc event lifetimes and expectation times calculated for different substorm phases show that the longest arc‐dominated periods are found during growth phases, while the longest arc waiting times occur during expansion phases. Most of the arc events end when arcs evolve to more complex structures. This is true for all substorm phases. Based on the number of images of auroral arcs and the durations of substorm phases, we conclude that a randomly selected auroral arc most likely belongs to a substorm expansion phase. A small time delay, of the order of a minute, is observed between the magnetic signature of the substorm onset (i.e., the beginning of the negative bay) and the auroral breakup (i.e., the growth phase arc changing into a dynamic display). The magnetic onset was observed to precede the structural change in the auroral display. A longer delay of a few minutes was found between the beginning of the growth phase and the first detected auroral structure.
Fresh and evolutionary‐type field‐aligned irregularities generated near sunrise terminator due to overshielding electric fields
Authors: Tulasi Ram S. , Ajith K. K. , Yamamoto M. , Otsuka Y. , Yokoyama T. , Niranjan K. , Gurubaran S.
Published: June 2015

The unusual evolution of fresh and intense field‐aligned irregularities (FAI) near sunrise terminator which further sustained for more than 90 min of postsunrise period was observed by Equatorial Atmosphere Radar at Kototabang during a minor geomagnetic storm period. These FAI echoes were initially observed around 250–350 km altitudes, growing upward under eastward polarization electric fields indicating the plasma bubbles that are fully depleted along the flux tube. The background low‐latitude F layer dynamics that lead to the development of these dawn time FAI have been investigated from two ionosondes at near magnetic conjugate low‐latitude locations. A minor geomagnetic storm was in progress which did not appear to cause any large electric field perturbations at preceding postsunset to midnight period over Indonesian sector. However, the prompt penetration of overshielding electric fields associated with sudden northward turning of interplanetary magnetic field Bz caused spectacular ascent of F layer and development of fresh, intense, and upward evolutionary plasma bubbles near sunrise terminator.
The Palos Verdes Fault offshore Southern California: Late Pleistocene to present tectonic geomorphology, seascape evolution, and slip rate estimate based on AUV and ROV surveys
Authors: Brothers Daniel S. , Conrad James E. , Maier Katherine L. , Paull Charles K. , McGann Mary , Caress David W.
Published: June 2015

The Palos Verdes Fault (PVF) is one of few active faults in Southern California that crosses the shoreline and can be studied using both terrestrial and subaqueous methodologies. To characterize the near‐seafloor fault morphology, tectonic influences on continental slope sedimentary processes and late Pleistocene to present slip rate, a grid of high‐resolution multibeam bathymetric data, and chirp subbottom profiles were acquired with an autonomous underwater vehicle (AUV) along the main trace of PVF in water depths between 250 and 600 m. Radiocarbon dates were obtained from vibracores collected using a remotely operated vehicle (ROV) and ship‐based gravity cores. The PVF is expressed as a well‐defined seafloor lineation marked by subtle along‐strike bends. Right‐stepping transtensional bends exert first‐order control on sediment flow dynamics and the spatial distribution of Holocene depocenters; deformed strata within a small pull‐apart basin record punctuated growth faulting associated with at least three Holocene surface ruptures. An upper (shallower) landslide scarp, a buried sedimentary mound, and a deeper scarp have been right‐laterally offset across the PVF by 55 ± 5, 52 ± 4 , and 39 ± 8 m, respectively. The ages of the upper scarp and buried mound are approximately 31 ka; the age of the deeper scarp is bracketed to 17–24 ka. These three piercing points bracket the late Pleistocene to present slip rate to 1.3–2.8 mm/yr and provide a best estimate of 1.6–1.9 mm/yr. The deformation observed along the PVF is characteristic of strike‐slip faulting and accounts for 20–30% of the total right‐lateral slip budget accommodated offshore Southern California.
On the Mechanism of Cuprate Crystal Growth: The Role of Mixed Metal Carbonates
Authors: Green David C. , Boston Rebecca , Glatzel Stefan , Lees Martin R. , Wimbush Stuart C. , Potticary Jason , Ogasawara Wataru , Hall Simon R.
Published: June 2015

The mechanism of formation of the superconductor Bi2Sr2CaCu2O8+x
(Bi‐2212) has been an open question since its discovery in 1988. By controlling crystal growth through the use of biopolymers as multivalent cation chelating agents, it is demonstrated through X‐ray diffraction and thermogravimetric analysis, that it is the formation of a mixed metal carbonate eutectic that promotes the formation of the target phase. X‐ray diffraction experiments, supported by infrared spectroscopy, identify this phase as (Sr1−x
Ca
x
)CO3. This knowledge allows to further reduce the eutectic melting point by the incorporation of a biopolymer rich in potassium ions, resulting in the scalable formation of Bi‐2212 at a temperature 50 °C lower than has been achieved previously.
Restoring Intrinsic Properties of Electromagnetic Radiators Using Ultralightweight Integrated Metasurface Cloaks
Authors: Jiang Zhi Hao , Sieber Peter E. , Kang Lei , Werner Douglas H.
Published: June 2015

The concept of invisibility has garnered long‐standing interest throughout human history but has only been realized experimentally within the past decade, albeit over a limited bandwidth. While the physical wave phenomenon of a reduced scattering signature has been demonstrated with different cloaking methods such as transformation optics and scattering cancellation, such technology has yet to be incorporated into any practical real‐world devices. Through the use of quasi‐2D functional metasurfaces, the long‐standing issue of simultaneous mutual coupling and radiation blockage is addressed that occurs when two or more electromagnetic radiators are placed in close proximity to one another. The proposed compact and ultralightweight metasurfaces, comprising arrays of subwavelength electric and magnetic resonators with tailored dispersive properties, are capable of fully restoring the intrinsic properties of real‐world electromagnetic radiators when placed in a multiradiator environment. This work introduces a general design approach to bridge the gap between the theory and practice for cloaks, which is applicable to microwave, terahertz, and optical radiators, as well as acoustic and thermal sources. Moreover, this technology provides an unprecedented opportunity for enabling high‐density deployment of radiating systems with low interference and undistorted signal wave fronts.
Optimizing the Size of Micellar Nanoparticles for Efficient siRNA Delivery
Authors: Liang Shi , Yang Xian‐Zhu , Du Xiao‐Jiao , Wang Hong‐Xia , Li Hong‐Jun , Liu Wei‐Wei , Yao Yan‐Dan , Zhu Yan‐Hua , Ma Yin‐Chu , Wang Jun , Song Er‐Wei
Published: June 2015

Delivery of small interfering RNA (siRNA) by nanocarriers has shown promising therapeutic potential in cancer therapy. However, poor understanding of the correlation between the physicochemical properties of nanocarriers and their interactions with biological systems has significantly hindered its anticancer efficacy. Herein, in order to identify the optimal size of nanocarriers for siRNA delivery, different sized cationic micellar nanoparticles (MNPs) (40, 90, 130, and 180 nm) are developed that exhibit similar siRNA binding efficacies, shapes, surface charges, and surface chemistries (PEGylation) to ensure size is the only variable. Size‐dependent biological effects are carefully and comprehensively evaluated through both in vitro and in vivo experiments. Among these nanocarriers, the 90 nm MNPs show the optimal balance of prolonged circulation and cellular uptake by tumor cells, which result in the highest retention in tumor cells. In contrast, larger MNPs are rapidly cleared from the circulation and smaller MNPs are inefficiently taken up by tumor cells. Accordingly, 90 nm MNPs carrying polo‐like kinase 1 (Plk1)‐specific siRNA (siPlk1) show superior antitumor efficacy, indicating that 90 nm could either be the optimal size for systemic delivery of siRNA or close to it. Our findings provide valuable information for rationally designing nanocarriers for siRNA‐based cancer therapy in the future.
High‐Performance Ta2O5/Al‐Doped Ag Electrode for Resonant Light Harvesting in Efficient Organic Solar Cells
Authors: Zhao Dewei , Zhang Cheng , Kim Hyunsoo , Guo L. Jay
Published: June 2015

A efficient indium tin oxide (ITO)‐free transparent electrode based on an improved Ag film is designed by introducing small amount of Al during co‐deposition, producing ultrathin and smooth Ag film with low loss. A transparent electrode as thin as 4 nm is achieved by depositing the film on top of Ta2O5 layer, and organic solar cells based on such ultrathin electrode are built, producing power conversion efficiency over 7%. The device efficiency can be optimized by simply tuning Ta2O5 layer thickness external to the organic photovoltaic (OPV) structure to create an optical cavity resonance inside the photoactive layer. Therefore Ta2O5/Al‐doped Ag films function as a high‐performance electrode with high transparency, low resistance, improved photon management capability and mechanical flexibility.
Phthalic anhydride production from hemicellulose solutions: Technoeconomic analysis and life cycle assessment
Authors: Lin Zhaojia , Ierapetritou Marianthi , Nikolakis Vladimiros
Published: June 2015

The process synthesis, technoeconomic analysis, and life cycle assessment (LCA) of a novel route for phthalic anhydride (PAN) production from hemicellulose solutions are presented. The production contains six steps including dehydration of xylose to furfural, reductive decarbonylation of furfural to furan, oxidation of furfural to maleic anhydride (MA), Diels‐Alder cycloaddition of furan, and MA to exo−4,10‐dioxa‐tricyclo[5.2.1.0]dec‐8‐ene‐3,5‐dione followed by dehydration to PAN in the presence of mixture of methanesulfonic acid and acetic anhydride (AAN) which is converted to acetyl methanesulfonate and acetic acid (AAD), and dehydration of AAD to AAN. The minimum selling price of PAN is determined to be $810/metric ton about half of oil‐based PAN. The coproduction of high‐value products is essential to improve the economics. Biomass feedstock contributes to the majority of cost. LCA results shows that biomass‐based PAN has advantages over oil‐based PAN to reduce climate change and fossil depletion however requires more water usage. © 2015 American Institute of Chemical Engineers AIChE J, 61: 3708–3718, 2015
Exome sequencing expands the mechanism of SOX5‐associated intellectual disability: A case presentation with review of sox‐related disorders
Authors: Nesbitt Addie , Bhoj Elizabeth J. , McDonald Gibson Kristin , Yu Zhenming , Denenberg Elizabeth , Sarmady Mahdi , Tischler Tanya , Cao Kajia , Dubbs Holly , Zackai Elaine H. , Santani Avni
Published: June 2015

The SOX5 haploinsufficiency syndrome is characterized by global developmental delay, intellectual disability, language and motor impairment, and distinct facial features. The smallest deletion encompassed only one gene, SOX5 (OMIM 604975), indicating that haploinsufficiency of SOX5 contributes to neuro developmental delay. Although multiple deletions of the SOX5 gene have been reported in patients, none are strictly intragenic point mutations. Here, we report the identification of a de novo loss of function variant in SOX5 identified through whole exome sequencing. The proband presented with moderate developmental delay, bilateral optic atrophy, mildly dysmorphic features, and scoliosis, which correlates with the previously‐described SOX5‐associated phenotype. These results broaden the diagnostic spectrum of SOX5‐related intellectual disability. Furthermore it highlights the utility of exome sequencing in establishing an etiological basis in clinically and genetically heterogeneous conditions such as intellectual disability. © 2015 Wiley Periodicals, Inc.
Kovalent‐allosterische Kinase‐Inhibitoren
Authors: Weisner Jörn , Gontla Rajesh , van der Westhuizen Leandi , Oeck Sebastian , Ketzer Julia , Janning Petra , Richters André , Mühlenberg Thomas , Fang Zhizhou , Taher Abu , Jendrossek Verena , Pelly Stephen C. , Bauer Sebastian , van Otterlo Willem A. L. , Rauh Daniel
Published: June 2015

Proteinkinasen repräsentieren wichtige Knotenpunkte intrazellulärer Signalwege und sind somit an vielen physiologischen und pathologischen Prozessen beteiligt. Konformations‐abhängige Eigenschaften dienen hierbei der Feinregulation ihrer enzymatischen Aktivität und Katalyse‐unabhängigen Funktionen. Die Stabilisierung definierter Konformationen ermöglicht detaillierte Analysen solcher Konformations‐abhängiger Funktionen. Hier beschreiben wir das strukturbasierte Design, die Synthese und die Charakterisierung Pleckstrin‐Homologie(PH)‐Domänen‐abhängiger Akt‐Inhibitoren, die einen neuartigen kovalent‐allosterischen Bindungsmodus aufweisen. Durch die kovalente Modifizierung bestimmter Cysteine stabilisieren diese Moleküle die inaktive Kinasekonformation irreversibel. Ihre beträchtliche Inhibitorwirkung und Selektivität bezüglich verwandter Proteinkinasen machen sie zu einem neuartigen Hilfsmittel für die Erforschung chemisch‐biologischer und medizinischer Fragestellungen.
Einfluss der Solvatisierung auf die Elektronenanlagerung an Pyrimidin
Authors: Neustetter Michael , Aysina Julia , da Silva Filipe Ferreira , Denifl Stephan
Published: June 2015

Die Wechselwirkung niederenergetischer Elektronen mit Biomolekülen spielt eine wichtige Rolle bei der strahlungsinduzierten Mutation von biologischem Gewebe auf molekularer Ebene. Bei Elektronenenergien unter 15 eV ist die dissoziative Elektronenanlagerung einer der Hauptprozesse, die chemische Umwandlungen von Molekülen induzieren. Bisherige Gasphasenstudien hinsichtlich der ablaufenden Prozesse auf molekularer Ebene wurden mit einzelnen Biomolekülbausteinen wie Pyrimidin als Modellmolekül durchgeführt. Hier wurde die Elektronenanlagerung sowohl an einzelnen Pyrimidinmolekülen als auch reinen oder hydratisierten Clustern untersucht. Im Unterschied zum isolierten und hydratisierten Fall, in denen kein anionisches Monomer detektiert werden konnte, gelang es, das Molekülanion bei reinen Clustern zu beobachten. Zusätzlich gibt es Hinweise darauf, dass die Fragmentierung des Pyrimidinrings unter Elektroneneinfang durch Solvatisierung effizient unterdrückt wird.
Synthesis of Previously Inaccessible Borylated Heterocycle Motifs Using Novel Boron‐Containing Amphoteric Molecules
Authors: Trinchera Piera , Corless Victoria B. , Yudin Andrei K.
Published: June 2015

The photoredox‐organocatalyzed α‐alkylation of the α‐MIDA boryl aldehyde with a range of α‐bromoketones resulted in the first examples of boron‐containing 1,4‐dicarbonyl compounds. These novel trifunctional amphoteric molecules, which bear an additional, strategically placed electrophilic site compared to the starting amphoteric α‐boryl aldehyde, were subjected to double‐condensation reactions in the presence of various nucleophiles. As a result, a variety of synthetically challenging 3‐borylated pyrroles and furans and 4‐borylated pyridazines were generated. The borylated regioisomers accessible with this condensation‐based strategy are distinctly different from those arising from the well‐known lithiation and CH activation processes.
Asymmetric Donor–π‐Acceptor‐Type Benzo‐Fused Aza‐BODIPYs: Facile Synthesis and Colorimetric Properties
Authors: Zheng Wei , Wang Bei‐Bei , Li Cheng‐Hui , Zhang Jing‐Xuan , Wan Cheng‐Zhang , Huang Jia‐Hao , Liu Jian , Shen Zhen , You Xiao‐Zeng
Published: June 2015

Novel aza‐diisoindolylmethene and their BF2‐chelating complexes (benzo‐fused aza‐BODIPYs) were synthesized on a large scale and in a facile manner from phthalonitrile in tBuOK‐DMF solution. The unique asymmetric donor–π‐acceptor structure facilitates BN bond detachment in the presence of trifluoroacetic acid (TFA) in dichloromethane, resulting in sharp color change from red to colorless, with over 250 nm hypsochromic shift in the absorption maximum. This colorimetric process can be reversed by adding a very small amount of proton‐accepting solvents or compounds. A 1H and 11B NMR spectroscopy study and also density functional theory (DFT) calculations suggest that TFA‐induced BN bond cleavage may disrupt the whole π‐conjugation of the BODIPY molecule, resulting in significant colorimetric behavior.
Covalent‐Allosteric Kinase Inhibitors
Authors: Weisner Jörn , Gontla Rajesh , van der Westhuizen Leandi , Oeck Sebastian , Ketzer Julia , Janning Petra , Richters André , Mühlenberg Thomas , Fang Zhizhou , Taher Abu , Jendrossek Verena , Pelly Stephen C. , Bauer Sebastian , van Otterlo Willem A. L. , Rauh Daniel
Published: June 2015

Targeting and stabilizing distinct kinase conformations is an instrumental strategy for dissecting conformation‐dependent signaling of protein kinases. Herein the structure‐based design, synthesis, and evaluation of pleckstrin homology (PH) domain‐dependent covalent‐allosteric inhibitors (CAIs) of the kinase Akt is reported. These inhibitors bind covalently to a distinct cysteine of the kinase and thereby stabilize the inactive kinase conformation. These modulators exhibit high potency and selectivity, and represent an innovative approach for chemical biology and medicinal chemistry research.
Highly Enantioselective Nucleophilic Dearomatization of Pyridines by Anion‐Binding Catalysis
Authors: García Mancheño Olga , Asmus Sören , Zurro Mercedes , Fischer Theresa
Published: June 2015

The asymmetric dearomatization of N‐heterocycles is an important synthetic method to gain bioactive and synthetically valuable chiral heterocycles. However, the catalytic enantio‐ and regioselective dearomatization of the simplest six‐membered‐ring N‐heteroarenes, the pyridines, is still very challenging. The first anion‐binding‐catalyzed, highly enantioselective nucleophilic dearomatization of pyridines with triazole‐based H‐bond donor catalysts is presented. Contrary to other more common NH‐based H‐bond donors, this type of organocatalyst shows a prominent higher C2‐regioselectivity and is able to promote high enantioinductions via formation of a close chiral anion‐pair complex with a preformed N‐acyl pyridinium ionic intermediate. This method offers a straightforward and useful synthetic approach to chiral N‐heterocycles from abundant and readily available pyridines.
Atomic‐Layer‐Confined Doping for Atomic‐Level Insights into Visible‐Light Water Splitting
Authors: Lei Fengcai , Zhang Lei , Sun Yongfu , Liang Liang , Liu Katong , Xu Jiaqi , Zhang Qun , Pan Bicai , Luo Yi , Xie Yi
Published: June 2015

A model of doping confined in atomic layers is proposed for atomic‐level insights into the effect of doping on photocatalysis. Co doping confined in three atomic layers of In2S3 was implemented with a lamellar hybrid intermediate strategy. Density functional calculations reveal that the introduction of Co ions brings about several new energy levels and increased density of states at the conduction band minimum, leading to sharply increased visible‐light absorption and three times higher carrier concentration. Ultrafast transient absorption spectroscopy reveals that the electron transfer time of about 1.6 ps from the valence band to newly formed localized states is due to Co doping. The 25‐fold increase in average recovery lifetime is believed to be responsible for the increased of electron–hole separation. The synthesized Co‐doped In2S3 (three atomic layers) yield a photocurrent of 1.17 mA cm−2 at 1.5 V vs. RHE, nearly 10 and 17 times higher than that of the perfect In2S3 (three atomic layers) and the bulk counterpart, respectively.
The Effect of Solvation on Electron Attachment to Pure and Hydrated Pyrimidine Clusters
Authors: Neustetter Michael , Aysina Julia , da Silva Filipe Ferreira , Denifl Stephan
Published: June 2015

The interaction of low‐energy electrons with biomolecules plays an important role in the radiation‐induced alteration of biological tissue at the molecular level. At electron energies below 15 eV, dissociative electron attachment is one of the most important processes in terms of the chemical transformation of molecules. So far, a common approach to study processes at the molecular level has been to carry out investigations with single biomolecular building blocks like pyrimidine as model molecules. Electron attachment to single pyrimidine, as well as to pure clusters and hydrated clusters, was investigated in this study. In striking contrast to the situation with isolated molecules and hydrated clusters, where no anionic monomer is detectable, we were able to observe the molecular anion for the pure clusters. Furthermore, there is evidence that solvation effectively prevents the ring fragmentation of pyrimidine after electron capture.
Light‐ and Humidity‐Induced Motion of an Acidochromic Film
Authors: Zhang Lidong , Naumov Panče
Published: June 2015

A smart acidochromic agarose‐based film with 1,4‐bis(para‐hydroxystyryl)benzene as the pH‐responsive fluorophore was prepared. This film can simultaneously harness the chemical potential of light and aerial humidity gradients to convert them into mechanical work. The strong reversible hygroscopicity of the agarose matrix induces swift locomotion by mechanical deformation owing to exchange of water with the surroundings. Driven by humidity, a 20 mg composite film coupled to a piezoelectric bending transducer sensor generates a peak output of approximately 80 mV, which corresponds to a power density of 25 μW kg−1. Excitation with UV light triggers isomerization of the chromophore, which appears as reshaping by spiraling, bending, or twisting of the film. The material also responds to changes in the pH value by reversible protonation of the fluorophore with rapid changes in color and fluorescence. The threefold sensing capability of this smart material could be utilized for the fabrication of multiresponsive actuating dynamic elements in biomedicine and soft robotics.
Metal–Organic Frameworks Incorporating Various Alkoxy Pendant Groups: Hollow Tubular Morphologies, X‐ray Single‐Crystal Structures, and Selective Carbon Dioxide Adsorption Properties
Authors: Prasad Thazhe Kootteri , Suh Myunghyun Paik
Published: June 2015

Eight porous metal–organic frameworks (MOFs) incorporating various alkoxy pendant groups (−OCnH2n+1; n=1–8) in the channels have been synthesized. All MOFs have macrosized, hollow, single‐crystal morphologies independent of the type of alkoxy pendant groups. The X‐ray single‐crystal structures indicate that the MOFs have doubly interpenetrated 3D frameworks that generate clover‐shaped 1D channels, the window sizes of which reduce as the length of the alkoxy pendant groups increases from −OCH3 to −OC8H17. The hollow axes of the tubular crystals are parallel to the 1D channels of the MOFs, which suggests that the hollow crystal is grown by the unidirectional addition of pillar ligands to the 2D network. Among the activated MOFs, only the MOFs with methoxy and ethoxy pendant groups show selective CO2 adsorption over N2 and CH4, whereas those with longer alkoxy pendant groups barely adsorb CO2 at room temperature, which implies that the pendant doors of the MOFs should have an appropriate length for selective CO2 capture.
Copper(II)‐Mediated Self‐Assembly of Hairpin Peptides and Templated Synthesis of CuS Nanowires
Authors: Wang Chengdong , Sun Yawei , Wang Jiqian , Xu Hai , Lu Jian R.
Published: June 2015

The self‐assembly of peptides and proteins under well‐controlled conditions underlies important nanostructuring processes that could be harnessed in practical applications. Herein, the synthesis of a new hairpin peptide containing four histidine residues is reported and the self‐assembly process mediated by metal ions is explored. The work involves the combined use of circular dichroism, NMR spectroscopy, UV/Vis spectroscopy, AFM, and TEM to follow the structural and morphological details of the metal‐coordination‐mediated folding and self‐assembly of the peptide. The results indicate that by forming a tetragonal coordination geometry with four histidine residues, copper(II) ions selectively trigger the peptide to fold and then self‐assemble into nanofibrils. Furthermore, the copper(II)‐bound nanofibrils template the synthesis of CuS nanowires, which display a near‐infrared laser‐induced thermal effect.
Indolizino[5,6‐b]quinoxaline Derivatives: Intramolecular Charge Transfer Characters and NIR Fluorescence
Authors: Kojima Mitsuru , Hayashi Hironobu , Aotake Tatsuya , Ikeda Shinya , Suzuki Mitsuharu , Aratani Naoki , Kuzuhara Daiki , Yamada Hiroko
Published: June 2015

Indolizino[5,6‐b]quinoxaline derivatives (1 a and 1 b) with a push–pull structure were prepared to show intramolecular charge‐transfer properties. Compounds 1 a and 1 b are strongly fluorescent in aprotic solvents while symmetrical derivatives (2 a and 2 b) were non‐fluorescent. The π‐expanded α–α linked dimer (10) of indolizino[5,6‐b]quinoxaline 1 b was serendipitously obtained to show NIR absorption over 800 nm and the fluorescence edge reached to 1400 nm.
Findings from the National Birth Defects Prevention Study: Interpretation and translation for the clinician
Authors: Alwan Sura , Chambers Christina D.
Published: June 2015

Background

The National Birth Defects Prevention Study (NBDPS) is a large U.S. multi‐site case–control study first established in 1996 to identify potentially preventable environmental causes and genetic risk factors for more than 30 selected categories of major birth defects.

Methods

Numerous reports with both positive and negative findings have been produced by the NBDPS, and many have influenced clinical practice. Many NBDPS reports have included novel findings, and in some cases these findings could only be considered hypothesis‐generating. Other reports have met criteria for causality such as replication of findings in other studies, biological plausibility, and coherence.

Results

However, translation of even strongly supported associations, in some cases, has required clinicians to learn to communicate information to patients about small and uncertain absolute risks in the context of the potential effects of under‐ or poorly treated maternal conditions.

Conclusion

The NBDPS has continued to play an important role as a rich U.S. data source that can advance the understanding of maternal conditions and their treatments in relation to birth defects. Birth Defects Research (Part A) 103:721–728, 2015. © 2015 Wiley Periodicals, Inc.
Antimicrobial mechanism of resveratrol‐trans‐dihydrodimer produced from peroxidase‐catalyzed oxidation of resveratrol
Authors: Mora‐Pale Mauricio , Bhan Namita , Masuko Sayaka , James Paul , Wood Julia , McCallum Scott , Linhardt Robert J. , Dordick Jonathan S. , Koffas Mattheos A. G.
Published: June 2015

Plant polyphenols are known to have varying antimicrobial potencies, including direct antibacterial activity, synergism with antibiotics and suppression of bacterial virulence. We performed the in vitro oligomerization of resveratrol catalyzed by soybean peroxidase, and the two isomers (resveratrol‐trans‐dihydrodimer and pallidol) produced were tested for antimicrobial activity. The resveratrol‐trans‐dihydrodimer displayed antimicrobial activity against the Gram‐positive bacteria Bacillus cereus, Listeria monocytogenes, and Staphylococcus aureus (minimum inhibitory concentration (MIC) = 15.0, 125, and 62.0 μM, respectively) and against Gram‐negative Escherichia coli (MIC = 123 μM, upon addition of the efflux pump inhibitor Phe‐Arg‐β‐naphthylamide). In contrast, pallidol had no observable antimicrobial activity against all tested strains. Transcriptomic analysis implied downregulation of ABC transporters, genes involved in cell division and DNA binding proteins. Flow cytometric analysis of treated cells revealed a rapid collapse in membrane potential and a substantial decrease in total DNA content. The active dimer showed >90% inhibition of DNA gyrase activity, in vitro, by blocking the ATP binding site of the enzyme. We thus propose that the resveratrol‐trans‐dihydrodimer acts to: (1) disrupt membrane potential; and (2) inhibit DNA synthesis. In summary, we introduce the mechanisms of action and the initial evaluation of an active bactericide, and a platform for the development of polyphenolic antimicrobials. Biotechnol. Bioeng. 2015;112: 2417–2428. © 2015 Wiley Periodicals, Inc.
Downregulation of RND3/RhoE in glioblastoma patients promotes tumorigenesis through augmentation of notch transcriptional complex activity
Authors: Liu Baohui , Lin Xi , Yang Xiangsheng , Dong Huimin , Yue Xiaojing , Andrade Kelsey C. , Guo Zhentao , Yang Jian , Wu Liquan , Zhu Xiaonan , Zhang Shenqi , Tian Daofeng , Wang Junmin , Cai Qiang , Chen Qizuan , Mao Shanping , Chen Qianxue , Chang Jiang
Published: June 2015

Activation of Notch signaling contributes to glioblastoma multiform (GBM) tumorigenesis. However, the molecular mechanism that promotes the Notch signaling augmentation during GBM genesis remains largely unknown. Identification of new factors that regulate Notch signaling is critical for tumor treatment. The expression levels of RND3 and its clinical implication were analyzed in GBM patients. Identification of RND3 as a novel factor in GBM genesis was demonstrated in vitro by cell experiments and in vivo by a GBM xenograft model. We found that RND3 expression was significantly decreased in human glioblastoma. The levels of RND3 expression were inversely correlated with Notch activity, tumor size, and tumor cell proliferation, and positively correlated with patient survival time. We demonstrated that RND3 functioned as an endogenous repressor of the Notch transcriptional complex. RND3 physically interacted with NICD, CSL, and MAML1, the Notch transcriptional complex factors, promoted NICD ubiquitination, and facilitated the degradation of these cofactor proteins. We further revealed that RND3 facilitated the binding of NICD to FBW7, a ubiquitin ligase, and consequently enhanced NICD protein degradation. Therefore, Notch transcriptional activity was inhibited. Forced expression of RND3 repressed Notch signaling, which led to the inhibition of glioblastoma cell proliferation in vitro and tumor growth in the xenograft mice in vivo. Downregulation of RND3, however, enhanced Notch signaling activity, and subsequently promoted glioma cell proliferation. Inhibition of Notch activity abolished RND3 deficiency‐mediated GBM cell proliferation. We conclude that downregulation of RND3 is responsible for the enhancement of Notch activity that promotes glioblastoma genesis.
Using a nano‐flare probe to detect RNA in live donor cells prior to somatic cell nuclear transfer
Authors: Fu Bo , Ren Liang , Liu Di , Ma Jian‐zhang , An Tie‐zhu , Yang Xiu‐qin , Ma Hong , Guo Zhen‐hua , Zhu Meng , Bai Jing
Published: June 2015

Many transgenes are silenced in mammalian cells (donor cells used for somatic cell nuclear transfer [SCNT]). Silencing correlated with a repressed chromatin structure or suppressed promoter, and it impeded the production of transgenic animals. Gene transcription studies in live cells are challenging because of the drawbacks of reverse‐transcription polymerase chain reaction and fluorescence in situ hybridization. Nano‐flare probes provide an effective approach to detect RNA in living cells. We used 18S RNA, a housekeeping gene, as a reference gene. This study aimed to establish a platform to detect RNA in single living donor cells using a Nano‐flare probe prior to SCNT and to verify the safety and validity of the Nano‐flare probe in order to provide a technical foundation for rescuing silenced transgenes in transgenic cloned embryos. We investigated cytotoxic effect of the 18S RNA–Nano‐flare probe on porcine fetal fibroblasts, characterized the distribution of the 18S RNA–Nano‐flare probe in living cells and investigated the effect of the 18S RNA–Nano‐flare probe on the development of cloned embryos after SCNT. The cytotoxic effect of the 18S RNA–Nano‐flare probe on porcine fetal fibroblasts was dose‐dependent, and 18S RNA was detected using the 18S RNA–Nano‐flare probe. In addition, treating donor cells with 500 pM 18S RNA–Nano‐flare probe did not have adverse effects on the development of SCNT embryos at the pre‐implantation stage. In conclusion, we established a preliminary platform to detect RNA in live donor cells using a Nano‐flare probe prior to SCNT.
Preparation of Highly Active Nickel Catalysts Supported on Mesoporous Nanocrystalline γ‐Al2O3 for Methane Autothermal Reforming
Authors: Sepehri Soodeh , Rezaei Mehran
Published: June 2015

Autothermal reforming (ATR) of methane was carried out over nanocrystalline Al2O3‐supported Ni catalysts with various Ni loadings. Mesoporous nanocrystalline γ‐Al2O3 powder with high specific surface area was prepared by the sol‐gel method and employed as support for the nickel catalysts. The prepared samples were characterized by X‐ray diffraction, Brunauer‐Emmett‐Teller, temperature‐programmed reduction, temperature‐programmed hydrogenation, and scanning electron microscopy techniques. It is demonstrated that the methane conversion increased with increasing in Ni content and that the catalyst with 25 wt % Ni exhibited the highest activity and a stable catalytic performance in the ATR process, with a low degree of carbon formation. Furthermore, the effects of the reaction temperature, the calcination temperature, the steam/CH4 and O2/CH4 ratios, and the gas hourly space velocity on the catalytic performance of the 25 % Ni/Al2O3 catalyst were investigated.
Full Superstructure for Multiobjective Optimization of Multicolumn Chromatography for Ternary Separations
Authors: Agrawal Gaurav , Kawajiri Yoshiaki
Published: June 2015

In the past decades, many multicolumn chromatographic processes have been proposed and studied for multicomponent continuous separation. In this study, the optimal operation for ternary multicolumn chromatographic separation is obtained from a full superstructure which embeds many different operations. A multiobjective optimization problem was solved to analyze the trade‐off between the throughput and the purity of the target component. It was found that the throughput of the optimal operation found from the full superstructure is significantly higher than that of the generalized full cycle scheme in our former publication in 2012.
Highly Cytotoxic Bioconjugated Gold(I) Complexes with Cysteine‐Containing Dipeptides
Authors: Gutiérrez Alejandro , Marzo Isabel , Cativiela Carlos , Laguna Antonio , Gimeno M. Concepción
Published: June 2015

Several gold(I) complexes with cysteine‐containing dipeptides have been prepared starting from cystine by coupling different amino acids and using several orthogonal protections. The first step is the reaction of cystine, where the sulfur centre is protected as disulfide, with Boc2O in order to protect the amino group, followed by coupling of an amino acid ester; finally the disulfide bridge is broken with mercaptoethanol to afford the dipeptide derivative. Further reaction with [AuCl(PPh3)] gives the gold‐dipeptide‐phosphine species. Starting from these formally gold(I) thiolate–dipeptide phosphine complexes with the general formula [Au(SR)(PR3)] different structural modifications, such as change in the type of the amino protecting group, the type of phosphine, the number of gold(I) atoms per molecule, or the use of a non‐proteinogenic conformationally restricted amino acid ester, were introduced in order to evaluate their influence in the biological activity of the final complexes. The cytotoxic activity, in vitro, of these complexes was evaluated against different tumour human cell lines (A549, MiaPaca2 and Jurkat). The complexes show an outstanding cytotoxic activity with IC50 values in the very low micromolar range. Structure–activity relationship studies from the complexes open the possibility of designing more potent and promising gold(I) anticancer agents.
ChemInform Abstract: Metal‐Free Csp3—N Bond Cleavage of Amides Using tert‐Butyl Hydroperoxide as Oxidant.
Authors: Guo Shengmei , Zhu Zheng , Lu Lin , Zhang Wenbiao , Gong Jiuhan , Cai Hu
Published: June 2015

The C—N bond cleavage of dimethyl acetamide (II) under oxidative conditions is demonstrated.
ChemInform Abstract: Magic Angle Spinning NMR Spectroscopy: A Versatile Technique for Structural and Dynamic Analysis of Solid‐Phase Systems
Authors: Polenova Tatyana , Gupta Rupal , Goldbourt Amir
Published: June 2015

Review: 155 refs.
Prepare for a crisis by understanding what information cannot/must be disclosed
Authors: Prywes Daniel I. , Sobel Scott
Published: June 2015

Managing the legal and public relations dimensions of a crisis is an art, not a science. Legal restrictions on university speech must be understood and harmonized with the requirements of an effective public relations strategy. If your institution's response is poor, its reputation could be seriously damaged. But if handled well, a crisis can be an opportunity for a university to demonstrate in practice and publicly its adherence to the high values that make it great.
Top 5 concerns about America's College Promise addressed
Authors: Sutton Halley
Published: June 2015

SAN ANTONIO, TEXAS — Barack Obama's proposal for America's College Promise has been met with both concerns and applause from those firmly entrenched in academia and those within the business sphere. “We had the same sort of cynicism in 2009 before we embarked on the student success and completion agenda,” said J. Noah Brown, current president and chief executive officer of the Association of Community College Trustees. Brown spoke on a panel of experts regarding America's College Promise during the annual American Association of Community Colleges convention.