bluuebunny/crossref_metadata_2025 huggingface dataset:
Impact of Musculoskeletal Ultrasound in an Outpatient Rheumatology Clinic
Authors: Micu Mihaela C. , Alcalde María , Sáenz José Ignacio , Crespo Manuel , Collado Paz , Bolboacă Sorana D. , Naredo Esperanza
Published: November 2012

Objective

To evaluate the impact of musculoskeletal ultrasound (MSUS) as a complementary method to clinical assessment on rapid diagnosis and therapeutic decisions in a busy outpatient rheumatology clinic.

Methods

Sixty patients with different musculoskeletal symptoms were included in the study. Three expert rheumatologists performed the clinical examination and filled out a standardized clinical report sheet with the following parameters: general and/or local diagnoses, planned systemic and/or local treatment, and their decision concerning the use of MSUS evaluation complementary to clinical examination. Another rheumatologist, blinded to clinical data, performed the MSUS assessment of the anatomic areas selected by the clinicians. The impact of the new information obtained by MSUS on the initial diagnosis and therapeutic strategy was estimated by the degree of change in the initial clinical diagnosis and therapy decisions.

Results

Of 60 patients (67 anatomic areas), MSUS was considered as necessary after clinical examination in 39 patients (65%), totaling 43 anatomic areas (64.17%). An overall change of the initial clinical diagnosis was present in 60% of the anatomic areas (P = 0.0175). In all of the anatomic areas (100%), the new diagnosis was more objective and detailed. An overall change of the initial systemic therapy was present in 25% of anatomic areas (P = 0.0014) and in 36% of anatomic areas (P = 0.095) for local therapy. A guided diagnostic aspiration was decided to be performed in 15% of anatomic areas and a guided therapeutic injection in 22% of anatomic areas.

Conclusion

Enhanced information obtained by MSUS evaluation leads to changes, with a significant impact on the initial diagnosis and treatment strategy designed after clinical examination.
Using Rituximab Plus Fludarabine and Cyclophosphamide as a Treatment for Refractory Mixed Cryoglobulinemia Associated With Lymphoma
Authors: Saadoun D. , Pineton de Chambrun M. , Hermine O. , Karras A. , Choquet S. , Jego P. , Decaux O. , Cacoub P.
Published: November 2012

Objective

Treatment of refractory mixed cryoglobulinemia (MC) with severe organ involvement remains challenging. Fludarabine, cyclophosphamide, and rituximab (FCR) treatment is highly effective for patients with chronic lymphocytic leukemia and marginal‐zone lymphoma. We first report the safety and efficacy of FCR treatment in severe and refractory MC vasculitis associated with lymphoma.

Methods

We report the safety and efficacy of fludarabine (40 mg/m2 orally on days 2–4), cyclophosphamide (250 mg/m2 orally on days 2–4), and rituximab (375 mg/m2 on day 1), every 4 weeks, for 3 to 6 cycles in 7 consecutive patients with severe and refractory MC.

Results

Clinical features of MC included purpura (n = 7), polyneuropathy (n = 6), and kidney (n = 4) and cardiac involvement (n = 2). Previous treatment included rituximab (n = 5), corticosteroids (n = 5), antiviral therapy (n = 5), cyclophosphamide (n = 3), and plasmapheresis (n = 2). All patients achieved clinical response, with 3 patients (42.9%) achieving a complete remission and 4 patients (57.1%) a partial remission. Cryoglobulin decreased from 0.94 to 0.41 gm/liter (P = 0.015). After a followup of 27 months, 2 patients experienced a relapse of MC. Five patients (71.4%) experienced side effects, including cytopenia (n = 5), pneumopathy (n = 2), and serum sickness (n = 1).

Conclusion

The FCR regimen represents an effective treatment in severe and refractory MC.
Wetting Properties of Steel Surfaces Modified by Laser Interference Metallurgy
Authors: Raillard Brice , Rémond Justine , Ramos‐Moore Esteban , Souza Nicolas , Gachot Carsten , Mücklich Frank
Published: November 2012

The wetting properties of 100Cr6 bearing steel surfaces modified using laser interference metallurgy (LIMET) are analyzed. The steel surfaces are structured with line‐like patterns with line‐spacing. The topography of the ridged surface is analyzed by means of white light interferometry and scanning electron microscopy and surface chemistry of the different topographic regions by Raman spectroscopy. Contact angle (CA) measurements are performed on modified and non‐irradiated surfaces, using bi‐distilled water and FVA2 industrial oil. The angles are measured parallel and perpendicular to the line‐pattern orientation. The topographical analysis shows steep line‐pattern produced by laser. Raman analysis indicates that the laser irradiation does not significantly change the chemical species of the modified surfaces. The CA measurements elucidates that the parallel orientation provides a better wetting of the surface, because the laser line‐pattern acts as capillary flow channels, whereas the perpendicular orientation imposes energy barrier thus preventing wetting. As expected, the wetting coverage is more effective for larger than for smaller periodic structures, due to the larger area of flat contact. These novel results highlight the relevant use of LIMET to tailor the wetting properties of steel surfaces.
Ultrathin Silica Films on Metals: The Long and Winding Road to Understanding the Atomic Structure
Authors: Shaikhutdinov Shamil , Freund Hans‐Joachim
Published: November 2012

This paper critically reviews the experimental and theoretical studies on the growth of ultrathin silica films onto metal single crystal substrates reported to date. The silica films on Mo(112) and Ru(0001) are discussed in more detail to demonstrate the key roles of the multi‐technique approach and interplay between experiment and theory in the quest for understanding the atomic structure of the films. The results show the structural complexity and diversity of silica overlayers on metals, providing further information towards our understanding of the atomic structure, structural dynamics and physical and chemical properties of silica and related materials.
Asymmetrische Katalyse mit Bis(hydroxyphenyl)diamid/Seltenerdmetall‐Komplexen
Authors: Kumagai Naoya , Shibasaki Masakatsu
Published: November 2012

Eine Serie von asymmetrischen Katalysatoren bestehend aus konformativ flexiblen, chiralen Amidliganden und Seltenerdmetallen wurde für die Protonentransferkatalyse entwickelt. Diese von Aminosäuren abgeleiteten Liganden bieten eine faszinierende chirale Plattform für die Bildung asymmetrischer Katalysatoren durch Komplexierung mit Seltenerdmetallen. Das Anwendungsspektrum dieser Katalysatorfamilie wurde durch die Entwicklung katalytischer Heterodimetallsysteme noch erweitert. Das Zusammenwirken von Wasserstoffbrückenbindung und Metallkoordination führte zu einer verblüffenden Substratspezifität und Stereokontrolle, und dank der dynamischen Natur der Katalysatoren ließ sich deren Funktion umschalten. In diesem Kurzaufsatz fassen wir unsere aktuellen Untersuchungen dieser Katalysatorklasse zusammen.
MiR‐16‐1 Plays a Role in Reducing Migration and Invasion of Glioma Cells
Authors: Li Xiangdong , Ling Nan , Bai Yanyan , Dong Wanli , Hui Guo‐Zhen , Liu Dinghua , Zhao Jun , Hu Jin
Published: November 2012

MicroRNAs (miRNAs) are novel small noncoding RNA molecules that regulate gene expression at the post transcriptional level. Compelling evidence shows that there are causative links between miRNAs deregulation and cancer development and progression. This study aims to explore the functions of miR‐16‐1 on proliferation, apoptosis, motility, and invasion of glioma cells. Quantitative real‐time PCR (qRT‐PCR) was performed to detect the expression of miR‐16‐1 in normal brain tissues and two glioma cell lines, including U251 and U87. CCK‐8, Annexin V/FITC (fluorescein isothiocyanate), wound healing, and transwell assays were used to evaluate the functions of miR‐16‐1 that involves cell proliferation, apoptosis, motility, and invasion. In addition, we conducted qRT‐PCR to examine mRNA expression levels of Zyxin, one of putative target genes of miR‐16‐1, in U251 glioma cells after transfecting with miR‐16‐1 mimics. As a result, miR‐16‐1 expression level was lower in U251 and U87 cells than normal brain tissues. After miR‐16‐1 was upregulated in U251 cells, cellular proliferation was notably attenuated but cell apoptosis was not significantly increased. Moreover, overexpression of miR‐16‐1 attenuated migration and invasion of glioma cells, and U251 cells transfected with miR‐16‐1 showed significantly lower endogenous mRNA levels of Zyxin than those transfected with nonspecific control miRNA or mock (P < 0.05). In summary, we demonstrated that miR‐16‐1 expression was markedly decreased in human glioma cell lines, and for the first time, described the roles of miR‐16‐1 in cellular proliferation, migration, and invasion abilities of high‐invasive glioma cells, and suggested that Zyxin may be one of putative target genes of miR‐16‐1. Anat Rec, 296:427–432, 2012. © 2012 Wiley Periodicals, Inc.
Variable Order Fractional Controllers
Authors: Valério Duarte , Sá da Costa José
Published: November 2012

This paper addresses variable order fractional controllers. Four situations where variable order fractional controllers may be used to cope with time‐varying plants are used as examples. In all cases a constant phase margin is sought, thus resulting in a constant overshoot in step responses, which is otherwise unattainable. The first two examples concern first generation Crone controllers for plants with time‐varying gains. The other two examples concern a logarithmic phase Crone controller for a plant with time‐varying poles and gain. Numerical simulation results are given for all examples.
Stability Margins and H∞ Co‐Design with Fractional‐Order PIλ Controllers
Authors: Wang De‐Jin , Gao Xue‐Li
Published: November 2012

This article considers the co‐design of gain and phase margins and H∞ performance for fractional‐delay systems using fractional‐order PIλ controllers. The stability region in the proportional–integral plane of the PIλ controller for a fixed fractional‐order λ is first determined graphically in terms of a stability equation method applicable to fractional‐delay systems. Then, in the stability region, the system performance design is carried out, including the classical gain‐margin and phase‐margin and the modern H∞‐norm constraint of the sensitivity function of the closed‐loop. A numerical example is given to show the superiorities of the fractional‐order PIλ controller over the integer‐order PI controller.
Integrating cell‐free biosyntheses of heme prosthetic group and apoenzyme for the synthesis of functional P450 monooxygenase
Authors: Kwon Yong‐Chan , Oh In‐Seok , Lee Nahum , Lee Kyung‐Ho , Yoon Yeo Joon , Lee Eun Yeol , Kim Byung‐Gee , Kim Dong‐Myung
Published: November 2012

Harnessing the isolated protein synthesis machinery, cell‐free protein synthesis reproduces the cellular process of decoding genetic information in artificially controlled environments. More often than not, however, generation of functional proteins requires more than simple translation of genetic sequences. For instance, many of the industrially important enzymes require non‐protein prosthetic groups for biological activity. Herein, we report the complete cell‐free biogenesis of a heme prosthetic group and its integration with concurrent apoenzyme synthesis for the production of functional P450 monooxygenase. Step reactions required for the syntheses of apoenzyme and the prosthetic group have been designed so that these two separate pathways take place in the same reaction mixture, being insulated from each other. Combined pathways for the synthesis of functional P450 monooxygenase were then further integrated with in situ assay reactions to enable real‐time measurement of enzymatic activity during its synthesis. Biotechnol. Bioeng. 2013; 110: 1193–1200. © 2012 Wiley Periodicals, Inc.
Improved production of 3‐hydroxypropionaldehyde by complex formation with bisulfite during biotransformation of glycerol
Authors: Sardari Roya R.R. , Dishisha Tarek , Pyo Sang‐Hyun , Hatti‐Kaul Rajni
Published: November 2012

3‐Hydroxypropionaldehyde (3HPA) is an important specialty chemical which can be produced from glycerol using resting cells of Lactobacillus reuteri. This biocatalytic route, however, suffers from substrate‐ and product‐mediated loss of enzyme activity within 2 h of biotransformation. In order to overcome the inhibitory effects of 3HPA, complex formation with sodium bisulfite was investigated, optimized and applied for in situ capture of the aldehyde during biotransformation of glycerol in a fed‐batch process. As a result, the activity of the cells was maintained for at least 18 h. The 3HPA produced per gram cell dry weight was increased 5.7 times compared to the batch production process, and 2.2 times compared to fed‐batch process without in situ complex formation. This approach may have potential for production and in situ removal of 3HPA after further process development. Biotechnol. Bioeng. 2013; 110: 1243–1248. © 2012 Wiley Periodicals, Inc.
Identification and quantification of atractylenolide I and atractylenolide III in Rhizoma Atractylodes Macrocephala by liquid chromatography–ion trap mass spectrometry
Authors: Chen Qinhua , He Hongsheng , Li Peng , Zhu Jun , Xiong Min
Published: November 2012

Rhizoma Atractylodes Macrocephala (RAM) is an important traditional Chinese medicinal herb that is used for treatment of dyspepsia and anorexia. The active ingredients, atractylenolide I (AO‐I) and atractylenolide III (AO‐III), were identified by direct‐injection ion trap‐mass spectrometry (IT‐MS) for collecting MSn spectra. The major fragment ions of AO‐I and AO‐III were confirmed by MSn both in negative ion mode and in positive ion mode. The possible main cleavage pathway of fragment ions was studied. The determinations of AO‐I and AO‐III were accomplished by liquid chromatography (LC) with UV and MS. The analytes provided good signals corresponding to the protonated molecular ions [M + H]+ and product ions. The precursor ions and product ions for quantification of AO‐III and AO‐I were m/z 249 → 231 and m/z 233 → 215, respectively, using selected ion monitoring by LC‐IT‐MS. Two methods were evaluated for a number of validation characteristics (repeatability, limit of detection, calibration range, and recovery). MS provides a high selectivity and sensitivity for determination of AO‐III and AO‐I in positive mode. After optimization of the methods, separation, identification and quantification of the two components in RAM were comprehensively tested by HPLC with UV and MS. Copyright © 2012 John Wiley & Sons, Ltd.
Enzymatic processes for the purification of trehalose
Authors: Wu Tsung‐Ta , Lin Sung‐Chyr , Shaw Je‐Fu
Published: November 2012

A dual‐enzyme process aiming at facilitating the purification of trehalose from maltose is reported in this study. Enzymatic conversion of maltose to trehalose usually leads to the presence of significant amount of glucose, by‐product of the reaction, and unreacted maltose. To facilitate the separation of trehalose from glucose and unreacted maltose, sequential conversion of maltose to glucose and glucose to gluconic acid under the catalysis of glucoamylase and glucose oxidase, respectively, is studied. This study focuses on the hydrolysis of maltose with immobilized glucoamylase on Eupergit® C and CM Sepharose. CM Sepharose exhibited a higher protein adsorption capacity, 49.35 ± 1.43 mg/g, and was thus selected as carrier for the immobilization of glucoamylase. The optimal reaction temperature and reaction pH of the immobilized glucoamylase for maltose hydrolysis were identified as 40°C and 4.0, respectively. Under such conditions, the unreacted maltose in the product stream of trehalose synthase‐catalyzed reaction was completely converted to glucose within 35 min, without detectable trehalose degradation. The conversion of maltose to glucose could be maintained at 0.92 even after 80 cycles in repeated‐batch operations. It was also demonstrated that glucose thus generated could be readily oxidized into gluconic acid, which can be easily separated from trehalose. We thus believe the proposed process of maltose hydrolysis with immobilized glucoamylase, in conjunction with trehalose synthase‐catalyzed isomerization and glucose oxidase‐catalyzed oxidation, is promising for the production and purification of trehalose on industrial scales. © 2012 American Institute of Chemical Engineers Biotechnol. Prog., 2013
Preventive effects of low‐dose aspirin on colorectal adenoma growth in patients with familial adenomatous polyposis: double‐blind, randomized clinical trial
Authors: Ishikawa Hideki , Wakabayashi Keiji , Suzuki Sadao , Mutoh Michihiro , Hirata Keiji , Nakamura Tomiyo , Takeyama Ikuko , Kawano Atsuko , Gondo Nobuhisa , Abe Takashi , Tokudome Shinkan , Goto Chiho , Matsuura Nariaki , Sakai Toshiyuki
Published: November 2012

There are several reports of clinical trials of aspirin in sporadic colon cancer. However, only one double‐blind trial of aspirin in patients with familial adenomatous polyposis (FAP) has been reported to date. This double‐blind, randomized, placebo‐controlled clinical trial was therefore performed to evaluate the influence of low‐dose aspirin enteric‐coated tablets (100 mg/day for 6–10 months) in 34 subjects with FAP (17 each in the aspirin and placebo groups). The increase in mean diameter of colorectal polyps tended to be greater in the placebo group compared with the aspirin group, which showed a response ratio, that is, aspirin response rate (number of subjects with reduced polyps/total)/placebo response rate (number of subjects with reduced polyps/total), of 2.33 (95% confidence interval: 0.72–7.55). Subgroup analysis revealed that the number of subjects with a mean baseline polyp diameter of ≤2 mm, and the diameter and number of polyps after intervention showed a significant reduction in the aspirin group. Adverse effects of aspirin, such as anastomotic ulcer, aphtha in the large intestine, and progression of anemia, occurred in three subjects. Moreover, none of the subjects developed colorectal cancer. The results thus indicated a potential for aspirin to reduce colorectal adenoma development in patients with FAP, but careful follow‐up is needed to avoid or rapidly counter severe adverse effects.
Cor triatriatum
Authors: Gupta Saurabh Kumar , Ramakrishnan S. , Doshi Shrenik
Published: November 2012

The coexistence of cor triatriatum and tetralogy of Fallot (TOF) is rare. Preoperative identification of cor triatriatum may be difficult owing to reduced pulmonary blood flow in patients with TOF. However, it is imperative to identify this rare combination as failure to identify obstruction to pulmonary venous egress may result in persistent pulmonary venous hypertension postoperatively. The authors discuss hemodynamic aspects of this rare coexistence in a 14‐month‐old child in whom pulmonary capillary wedge pressure was elevated despite right ventricular outflow obstruction. © 2012 Wiley Periodicals, Inc.
Redo of percutaneous renal denervation in a patient with recurrent resistant hypertension after primary treatment success
Authors: Lambert T. , Nahler A. , Leisch F.
Published: November 2012

A 79‐year‐old patient was treated with percutaneous renal denervation (RDN) due to resistant arterial hypertension in the summer of 2010. After primary treatment success with a decrease of blood pressure from 170/100 to 130/80 mm Hg 6 months postablation, the blood pressure rose again at 12 months despite maintenance of the pharmacologic regimen and the decision was made to perform a second RDN procedure. Three months following the second RDN procedure, blood pressure was lowered to 130/77 mm Hg. © 2012 Wiley Periodicals, Inc.
Transradial percutaneous coronary intervention for chronic total occlusion using sheathless technique and retrograde approach
Authors: Lin Cheng‐Jui , Fang Hsiu‐Yu , Chen Tien‐Hsing , Wu Chiung‐Jen
Published: November 2012

The use of 5 or 6 Fr sheath in transradial (TR) approach is often required due to the relative small radial artery size. A sheathless approach may overcome the limitation of small radial size which limits the TR approach. Our case showed successful angioplasty of the right coronary artery chronic total occlusion (CTO) by bilateral TR approaches, utilizing a 7‐Fr guide (7 Fr BL 3.5, 85 cm) for a retrograde sheathless approach, and a 6‐Fr Ikari 3.5 guide catheter for an antegrade approach. The sheathless TR technique can minimize vascular trauma and increase back‐up support for successful coronary intervention in CTO.© 2013 Wiley Periodicals, Inc.
Tuning the Surface Chemistry of Pd by Atomic C and H: A Microscopic Picture
Authors: Aleksandrov Hristiyan A. , Viñes Francesc , Ludwig Wiebke , Schauermann Swetlana , Neyman Konstantin M.
Published: November 2012

Palladium is crucial for industry‐related applications such as heterogeneous catalysis, energy production, and hydrogen technologies. In many processes, atomic H and C species are proposed to be present in the surface/near‐surface area of Pd, thus noticeably affecting its chemical activity. This study provides a detail and unified view on the interactions of the H and C species with Pd nanoparticles (NPs), which is indispensable for insight into their catalytic properties. Density functional calculations of the interplay of C and H atoms at various concentrations and sites on suitable Pd NPs have been performed, accompanied by catalysis‐relevant experiments on oxide‐supported bare and C‐modified Pd NPs. It is shown that on a Pd79NP a subsurface C atom destabilizes nearby atoms H at low coverage. Our experiments confirm that H atoms bind more weakly on C‐containing Pd NPs than on C‐free NPs. Various factors related to the presence of both H and C atoms on a Pd79surface, which may influence the penetration of H atoms from the surface into the subsurface area, have been investigated. Carbon atoms facilitate the subsurface penetration of atomic H both thermodynamically and kinetically when the surface is densely covered by H atoms. Moreover, subsurface H atoms are also energetically favored, even in the absence of C atoms, when several facets of the NP are covered by H atoms.
Adsorption‐Induced Restructuring and Early Stages of Carbon‐Nanotube Growth on Ni Nanoparticles
Authors: Wang Yuexia , Barcaro Giovanni , Negreiros Fabio R. , Visart de Bocarmé Thierry , Moors Mathieu , Kruse Norbert , Hou Marc , Fortunelli Alessandro
Published: November 2012

Carbon adsorption on various Ni surfaces is investigated as a function of coverage via a combination of first‐principles simulations and field emission microscope experiments. It is found that carbon can be efficiently stored as subsurface carbides, but with different energetics on differently oriented surfaces depending on their compactness and density of adsorption sites. In the resulting morphological reshaping, {113} facets are predicted to grow at the expense of {111} and {100} facets, in excellent agreement with experimental observations. Moreover, at high coverage on the {113} surface the carbon adsorption energy passes through a maximum after which a structural crossover is realized such that carbon atoms tend to ascend to the surface to form one‐dimensional chains (which are the precursors of graphitic nanostructures). This rationalizes the experimental observation of an incubation time between carbon storage and the beginning of catalytic growth, and provides insight into the early stages (nucleation mechanism) of carbon nanotubes on Ni nanoparticles.
Copper(I) and Silver(I) Bis(trifluoromethanesulfonyl)imide and Their Interaction with an Arene, Diverse Olefins, and an NTf2−‐Based Ionic Liquid
Authors: Stricker Marion , Oelkers Benjamin , Rosenau Carl Philipp , Sundermeyer Jörg
Published: November 2012

The chemistry of coinage metal bis(triflyl)imides of technological interest, CuNTf2 and AgNTf2, their synthesis and complexes with excess of comparatively weakly coordinating NTf2− as well as with ether, olefins, and the arene mesitylene are described. The existence of the solvent‐free pure phase [CuNTf2]∞ has not been evidenced so far. Contrary to the literature, in which the preparation of [CuNTf2]∞ is supposed to be carried out by reacting mesityl copper, [Cu(Mes)]5, and HNTf2, we found that in fact this reaction leads reproducibly to the interesting copper diarene sandwich complex [Cu(η3‐MesH)2][Cu(NTf2)2] (1) (MesH=1,3,5‐trimethylbenzene). The unexpectedly stable molecular etherate [Cu(Et2O)(NTf2)] (2) turned out to be the best precursor for CuNTf2 having only an inert and easily exchangeable solvent ligand. The coordination mode of NTf2− in 1 and 2 as well as in the hitherto unknown crystalline phase of [AgNTf2]∞ (3) is described. The complex formation, which takes place when dissolving 2 or 3 in the room temperature ionic liquid (RTIL) [emim]NTf2 ([emim]+=1‐ethyl‐3‐methylimidazolium), has been studied. Furthermore, the reaction of 1–3 towards the diolefins 1,5‐cyclooctadiene (COD), 2,5‐norbornadiene (NBD) and isoprene (2‐methylbuta‐1,3‐diene) and towards ethylene has been investigated. The products 4–13 of these conversions have been isolated and fully characterized by NMR‐ and IR spectroscopies, mass spectrometry, and elemental‐ and XRD analyses. The potential of [Cu(η3‐MesH)2][Cu(NTf2)2] (1), [Cu(Et2O)(NTf2)] (2) and [AgNTf2]∞ (3) as well as of [emim][M(NTf2)2] (M=Cu 4, Ag 5) as chemisorbers for ethylene was studied by NMR spectroscopy.
Synthesis and Two‐Photon Absorption Property Characterizations of Small Dendritic Chromophores Containing Functionalized Quinoxaliniod Heterocycles
Authors: Lin Tzu‐Chau , Lee Ying‐Hsuan , Liu Che‐Yu , Huang Bor‐Rong , Tsai Ming‐Yu , Huang Yu‐Jhen , Lin Ja‐Hon , Shen Yu‐Kai , Wu Cheng‐Yu
Published: November 2012

A series of star‐shaped multi‐polar chromophores (compounds 1–3) containing functionalized quinoxaline and quinoxalinoid (indenoquinoxaline and pyridopyrazine) units has been synthesized and characterized for their two‐photon absorption (2PA) properties both in the femtosecond and the nanosecond time domain. Under our experimental conditions, these model fluorophores are found to manifest strong and wide‐dispersed two‐photon absorption in the near‐infrared region. It is demonstrated that molecular structures with multi‐branched π frameworks incorporating properly functionalized quinoxalinoid units would possess large molecular nonlinear absorptivities within the studied spectral range. Effective optical‐power attenuation and stabilization behaviors in the nanosecond time domain of a selected representative dye molecule (i.e., compound 2) from this model compound set were also investigated and the results indicate that such structural motif could be a useful approach for the molecular design toward strong two‐photon‐absorbing material systems for quick‐responsive and broadband optical‐suppressing‐related applications, particularly to confront long laser pulses.
Simple Bipolar Hosts with High Glass Transition Temperatures Based on 1,8‐Disubstituted Carbazole for Efficient Blue and Green Electrophosphorescent Devices with “Ideal” Turn‐on Voltage
Authors: Huang Hong , Wang Yixin , Pan Biao , Yang Xiao , Wang Lei , Chen Jiangshan , Ma Dongge , Yang Chuluo
Published: November 2012

Two hybrids based on 1,8‐disubstituted carbazole, 1,8‐OXDCz and 1,8‐mBICz, have been designed and synthesized through a facile process. The incorporation of oxadiazole or N‐phenylbenzimidazole moieties at the 1,8‐positions of carbazole greatly improves its morphological stability, giving glass transition temperatures (Tg) as high as 138 and 154 °C, respectively. Blue phosphorescent organic light‐emitting devices (PhOLEDs) with 1,8‐mBICz exhibit almost the same performance as a similarly structured device based on the mCP host, and green PhOLEDs employing the new host material 1,8‐OXDCz exhibit an ideal turn‐on voltage (2.5 V at 1.58 cd m−2), a maximum current efficiency (ηc,max) of 73.9 cd A−1, and a power efficiency (ηp,max) of 89.7 lm W−1. These results are among the best performances of [Ir(ppy)3]‐based devices with simple device configurations.
Halogen Bonding from a Hard and Soft Acids and Bases Perspective: Investigation by Using Density Functional Theory Reactivity Indices
Authors: Pinter Balazs , Nagels Nick , Herrebout Wouter A. , De Proft Frank
Published: November 2012

Halogen bonds between the trifluoromethyl halides CF3Cl, CF3Br and CF3I, and dimethyl ether, dimethyl sulfide, trimethylamine and trimethyl phosphine were investigated using Pearson’s hard and soft acids and bases (HSAB) concept with conceptual DFT reactivity indices, the Ziegler–Rauk‐type energy‐decomposition analysis, the natural orbital for chemical valence (NOCV) framework and the non‐covalent interaction (NCI) index. It is found that the relative importance of electrostatic and orbital (charge transfer) interactions varies as a function of both the donor and acceptor molecules. Hard and soft interactions were distinguished and characterised by atomic charges, electrophilicity and local softness indices. Dual‐descriptor plots indicate an orbital σ hole on the halogen similar to the electrostatic σ hole manifested in the molecular electrostatic potential. The predicted high halogen‐bond‐acceptor affinity of N‐heterocyclic carbenes was evidenced in the highest complexation energy for the hitherto unknown CF3I⋅NHC complex. The dominant NOCV orbital represents an electron‐density deformation according to a n→σ*‐type interaction. The characteristic signal found in the reduced density gradient versus electron‐density diagram corresponds to the non‐covalent interaction between contact atoms in the NCI plots, which is the manifestation of halogen bonding within the NCI theory. The unexpected CX bond strengthening observed in several cases was rationalised within the molecular orbital framework.
Charge‐Neutral Amidinate‐Containing Iridium Complexes Capable of Efficient Photocatalytic Water Reduction
Authors: Yu Zhen‐Tao , Yuan Yong‐Jun , Cai Jian‐Guang , Zou Zhi‐Gang
Published: November 2012

Two new charge‐neutral iridium complexes, [Ir(tfm‐ppy)2(N,N′‐diisopropyl‐benzamidinate)] (1) and [Ir(tfm‐ppy)2(N,N′‐diisopropyl‐4‐diethylamino‐3,5‐dimethyl‐benzamidinate)] (2) (tfm‐ppy=4‐trifluoromethyl‐2‐phenylpyridine) containing an amidinate ligand and two phenylpyridine ligands were designed and characterised. The photophysical properties, electrochemical behaviours and emission quenching properties of these species were investigated. In concert with the cobalt catalyst [Co(bpy)3]2+, members of this new class of iridium complexes enable the photocatalytic generation of hydrogen from mixed aqueous solutions via an oxidative quenching pathway and display long‐term photostability under constant illumination over 72 h; one of these species achieved a relatively high turnover number of 1880 during this time period. In the case of complex 1, the three‐component homogeneous photocatalytic system proved to be more efficient than a related system containing a charged complex, [Ir(tfm‐ppy)2(dtb‐bpy)]+ (3, dtb‐bpy=4,4′‐di‐tert‐butyl‐2,2′‐dipyridyl). In combination with a rhodium complex as a water reduction catalyst, the performances of the systems using both complexes were also evaluated, and these systems exhibited a more efficient catalytic propensity for water splitting than did the cobalt‐based systems that have been studied previously.
Selective Dimerization of Lewis‐Acid/Base‐Stabilized Phosphanylalanes
Authors: Bodensteiner Michael , Timoshkin Alexey Y. , Peresypkina Eugenia V. , Vogel Ulf , Scheer Manfred
Published: November 2012

The reaction of [{(CO)5W}PRH2] (R=H, Ph) with H3Al⋅NR3 (R=Et, Me) leads to the formation of four‐membered heterocyclic compounds [({(CO)5W}P(H)AlH⋅ NEt3)2] and [({(CO)5W}PhPAlH⋅ NMe3)2]. Upon dissolving the solid compounds, fast equilibria between the isomers are observed on the NMR timescale. Further insight into the stability and reactivity of the isomers was gained by applying theoretical methods. DFT calculations predict that hydrogen elimination in the case of [({(CO)5W}PhPAlH⋅NMe3)2] may be reversible.
7,7,8,8‐Tetraaryl‐o‐quinodimethane Stabilized by Dibenzo Annulation: A Helical π‐Electron System That Exhibits Electrochromic and Unique Chiroptical Properties
Authors: Suzuki Takanori , Sakano Yuto , Iwai Tomohiro , Iwashita Shinichi , Miura Youhei , Katoono Ryo , Kawai Hidetoshi , Fujiwara Kenshu , Tsuji Yasushi , Fukushima Takanori
Published: November 2012

When two benzene rings are fused to a tetraaryl‐o‐quinodimethane skeleton, sterically hindered helical molecules 1 acquire a high thermodynamic stability. Because the tetraarylbutadiene subunit contains electron‐donating alkoxy groups, 1 undergo reversible two‐electron oxidation to 22+, which can be isolated as deeply colored stable salts. Intramolecular transfer of the point chirality (e.g., sec‐butyl) on the aryl groups to helicity induces a diastereomeric preference in dications 2 b2+ and 2 c2+, which represents an efficient method for enhancing circular‐dichroism signals. Thus, those redox pairs can serve as new electrochiroptical response systems. X‐ray analysis of dication 22+ revealed π–π stacking interaction of the diarylmethylium moieties, which is also present in solution. The stacking geometry is the key contributor to the chirosolvatochromic response.
Direct Conjugate Addition of Alkynes with α,β‐Unsaturated Carbonyl Compounds Catalyzed by NCN‐Pincer Ru Complexes
Authors: Ito Jun‐ichi , Fujii Kohei , Nishiyama Hisao
Published: November 2012

NCN‐pincer Ru‐complexes containing bis(oxazolinyl)phenyl ligands serve as suitable catalysts in the direct conjugate additions of α,β‐unsaturated carbonyl compounds, including ketones, esters, and amides, as well as vinylphosphonates, giving various β‐alkynyl carbonyl and phosphonate compounds. A bis(oxazolinyl)phenyl (phebox)–Ru complex also catalyzes the asymmetric conjugate addition of an alkyne with a β‐substituted, α,β‐unsaturated ketone to produce a chiral β‐alkynyl ketone.
Periadolescent maturation of the prefrontal cortex is sex‐specific and is disrupted by prenatal stress
Authors: Markham Julie A. , Mullins Sylvina E. , Koenig James I.
Published: November 2012

The prefrontal cortex (PFC) undergoes dramatic, sex‐specific maturation during adolescence. Adolescence is a vulnerable window for developing mental illnesses that show significant sexual dimorphisms. Gestational stress is associated with increased risk for both schizophrenia, which is more common among men, and cognitive deficits. We have shown that male, but not female, rats exposed to prenatal stress develop postpubertal deficits in cognitive behaviors supported by the prefrontal cortex. Here we tested the hypothesis that repeated variable prenatal stress during the third week of rat gestation disrupts periadolescent development of prefrontal neurons in a sex‐specific fashion. Using Golgi‐Cox stained tissue, we compared dendritic arborization and spine density of prelimbic layer III neurons in prenatally stressed and control animals at juvenile (day 20), prepubertal (day 30), postpubertal (day 56), and adult (day 90) ages (N = 115). Dendritic ramification followed a sex‐specific pattern that was disrupted during adolescence in prenatally stressed males, but not in females. In contrast, the impact of prenatal stress on the female PFC was not evident until adulthood. Prenatal stress also caused reductions in brain and body weights, and the latter effect was more pronounced among males. Additionally, there was a trend toward reduced testosterone levels for adult prenatally stressed males. Our findings indicate that, similarly to humans, the rat PFC undergoes sex‐specific development during adolescence and furthermore that this process is disrupted by prenatal stress. These findings may be relevant to both the development of normal sex differences in cognition as well as differential male–female vulnerability to psychiatric conditions. J. Comp. J. Comp. Neurol. 521:1828–1843, 2013. © 2012 Wiley Periodicals, Inc.
De novo expression of neurokinin‐1 receptors by spinoparabrachial lamina I pyramidal neurons following a peripheral nerve lesion
Authors: Saeed Abeer W. , Ribeiro‐da‐Silva Alfredo
Published: November 2012

Lamina I of the spinal dorsal horn is a major site of integration and transmission to higher centers of nociceptive information from the periphery. One important primary afferent population that transmits such information to the spinal cord expresses substance P (SP). These fibers terminate in contact with lamina I projection neurons that express the SP receptor, also known as the neurokinin‐1 receptor (NK‐1r). Three types of lamina I projection neurons have been described: multipolar, fusiform, and pyramidal. Most neurons of the first two types are thought to be nociceptive and express the NK‐1r, whereas most pyramidal neurons are nonnociceptive and do not express the NK‐1r. In this immunocytochemical and behavioral study, we induced a neuropathic pain‐like condition in the rat by means of a polyethylene cuff placed around in the sciatic nerve. We document that this lesion led to a de novo expression of NK‐1r on pyramidal neurons as well as a significant increase in SP‐immunoreactive innervation onto these neurons. These phenotypic changes were evident at the time of onset of neuropathic pain‐related behavior. Additionally, we show that, after a noxious stimulus (intradermal capsaicin injection), these NK‐1r on pyramidal neurons were internalized, providing evidence that these neurons become responsive to peripheral noxious stimulation. We suggest that the changes following nerve lesion in the phenotype and innervation pattern of pyramidal neurons are of significance for neuropathic pain and/or limb temperature regulation. J. Comp. Neurol. 521:1915–1928, 2013. © 2012 Wiley Periodicals, Inc.
Halogen‐Bonding Interactions with π Systems: CCSD(T), MP2, and DFT Calculations
Authors: Forni Alessandra , Pieraccini Stefano , Rendine Stefano , Gabas Fabio , Sironi Maurizio
Published: November 2012

Halogen bonding is a noncovalent interaction between a halogen atom and a nucleophilic site. Interactions involving the π electrons of aromatic rings have received, up to now, little attention, despite the large number of systems in which they are present. We report binding energies of the interaction between either NCX or PhX (X=F, Cl, Br, I) and the aromatic benzene system as determined with the coupled cluster with perturbative triple excitations method [CCSD(T)] extrapolated at the complete basis set limit. Results are compared with those obtained by Møller–Plesset perturbation theory to second order (MP2) and density functional theory (DFT) calculations by using some of the most common functionals. Results show the important role of DFT in studying this interaction.
Synthesis, growth, morphology of the semiorganic nonlinear optical crystal L‐glutamic acid hydrochloride and its structural, thermal and SHG characterizations
Authors: Dhanasekaran P. , Srinivasan K.
Published: November 2012

One of the halide derivatives of L‐glutamic acid which was identified as a semiorganic nonlinear optical material, L‐glutamic acid hydrochloride [HOOC(CH2)2CH(NH2)COOH.HCl], was grown as bulk single crystal and its significant properties were characterized. The stoichiometric title compound was synthesized and the solubility of its recrystallized form in DD water was determined in the temperature range 30–80 °C by gravimetric method. Structural confirmation was carried out by powder X‐ray diffraction study through lattice parameter verification. Optical quality smaller dimension single crystals were grown from aqueous solution by self nucleation through slow evaporation of solvent method and a large dimension single crystal was grown by slow cooling method with reversible seed rotation technique. Morphological importances of different growth facets of the as grown crystals were studied through optical goniometry. Unit cell structure of the grown crystal was refined by single crystal X‐ray diffraction analysis, functional groups present in the crystal responsible for various modes of vibrations were confirmed by FTIR spectroscopy analysis, thermal stability of the grown crytal was analysed by TG/DTA and DSC and second harmonic generation (SHG) of a fundamental Nd:YAG laser beam by Kurtz technique. Results indicate that the grown crystal is in stoichiometric composition and has significant improvement in its thermal and SHG properties when compared to pure L‐glutamic acid polymorphs.
Scalable and efficient key management for Mobile WiMAX networks
Authors: Gilanian Sadeghi Mohammad Mehdi , Mohd Ali Borhanuddin , Ma Maode , Ab Manan Jamalul‐lail
Published: November 2012

Efficiency and security are two critical but often conflicting issues in Multicast and Broadcast Service of IEEE 802.16e technology. Hence, it is vital to ensure an optimal scenario where neither security concerns, nor operational efficiency of the network is compromised. This paper proposes a new key management scheme called Scalable and Efficient Key Management Protocol, which uses a binary tree structure together with a B‐tree of order 2 structure. It focuses on improving key management performance of the existing techniques in terms of efficiency and scalability, without a loss in security. Scalable and Efficient Key Management Protocol dynamically establishes subgroups based on the current number of Mobile Stations in a WiMAX Base Station's coverage area. This will optimize the communications, computational and storage costs of the network. In addition, the scheme guarantees strong network scalability. Both analytical and simulation approaches have been carried out, and the results showed that the proposed scheme exhibits superior performance in terms of efficiency and scalability compared with existing schemes. Copyright © 2012 John Wiley & Sons, Ltd.
Modeling and analysis of access transparency and scalability in P2P distributed systems
Authors: Mousavi Khaneghah E. , Mirtaheri S. L. , Sharifi M. , Minaei Bidgoli B.
Published: November 2012

Peer‐to‐peer (P2P) systems have been developed with the goal of providing support for transparent and efficient sharing of scalable distributed resources wherein size scalability is limited by the costs of all types of transparencies, especially data access transparency, which are due to the need for frequent data exchanges between peers and other related communication overheads. We present a model that formulates the relationship between scalability and data access transparency in P2P distributed systems to figure out how large these systems can be scaled up, given the overheads of establishing data access transparency. To validate our model and show how our model can be deployed in real life, we consider a real P2P distributed system as a case study and evaluate how CPU utilization, bandwidth, and data request frequency parameters of our model relate to the amount of effort required by the system management to establish data access transparency. We then calculate the strength of the coefficient of correlation of scalability and data access transparency in the system. The degree of strength of this coefficient allows the system designer to decide at design time whether to allow the use of the model in the management of system at runtime or not. Copyright © 2012 John Wiley & Sons, Ltd.
Meiotic gene expression initiates during larval development in the sea urchin
Authors: Yajima Mamiko , Suglia Elena , Gustafson Eric A. , Wessel Gary M.
Published: November 2012

Background: Meiosis is a unique mechanism in gamete production and a fundamental process shared by all sexually reproducing eukaryotes. Meiosis requires several specialized and highly conserved genes whose expression can also identify the germ cells undergoing gametogenic differentiation. Sea urchins are echinoderms, which form a phylogenetic sister group of chordates. Sea urchin embryos undergo a feeding, planktonic larval phase in which they construct an adult rudiment prior to metamorphosis. Although a series of conserved meiosis genes (e.g., dmc1, msh5, rad21, rad51, and sycp1) is expressed in sea urchin oocytes, we sought to determine when in development meiosis would first be initiated. Results: We surveyed the expression of several meiotic genes and their corresponding proteins in the sea urchin Strongylocentrotus purpuratus. Surprisingly, meiotic genes are highly expressed not only in ovaries but beginning in larvae. Both RNA and protein localizations strongly suggest that meiotic gene expression initiates in tissues that will eventually give rise to the adult rudiment of the late larva. Conclusions: These results demonstrate that broad expression of the molecules associated with meiotic differentiation initiates prior to metamorphosis and may have additional functions in these cells, or mechanisms repressing their function, until later in development when gametogenesis begins. Developmental Dynamics, 2012. © 2012 Wiley Periodicals,Inc.
Multiple methods for calculating minimum ecological flux of the desiccated Lower Tarim River, Western China
Authors: Ye Zhaoxia , Shen Yanjun , Chen Yapeng
Published: November 2012

We estimated the minimum ecological influx in the lower Tarim River via the wetted perimeter method using the curvature technique. Calculations were based on river geomorphology data during the fifth and sixth ecological water conveyances. Results showed that the minimum ecological influx of the three control sections of the river (Yinsu, Alagan, and Yiganbjima) were 2.85, 3.76, and 1.76 m3/s, which accounted for 9.7%, 14%, and 6.9% of the multi‐year average annual discharges, respectively. Except for the dry season, annual ecological water demand of the river was 0.79 × 108 m3, excluding evaporation and leakage. Multiple methods were used to prove the rationality of the results. It is by using the Tennant method that the percentage of minimum ecological influx accounting for multi‐year average flux varied from 6.9% to 14% (average 10.2%), which is considered normal for the maintenance of river habitat. It is by using the R2Cross method that the minimum ecological influx of the lower Tarim River was 2.935 m3/s. These calculation results mirror the actual situation and serve as the base of water‐source distribution in lower Tarim River. Further research is required to validate and adjust the results according to long‐term hydrographic observations. Copyright © 2012 John Wiley & Sons, Ltd.