bluuebunny/crossref_metadata_2025 huggingface dataset:
Process Synthesis Principles in the Chromatographic Separation of Sugars from Biomass Hydrolysates
Authors: Saari P. , Hurme M.
Published: January 2011

Processing of biomass hydrolysates will increase in future as the sugar platform in biorefineries is employed to an increasing extent. Monosaccharides in the hydrolysates may be separated as a sugar group for fermentation or as individual sugars for use in the food and pharmaceutical industry. Chromatographic separation of sugars using ion exchange (IEX) resins is an interesting alternative for these purposes. The current status and use of IEX resins in the chromatographic separation of sugars is discussed. Based on industrial practice, process synthesis principles and heuristics are presented for the selection of a feasible IEX resin and separation sequence. Two case studies are presented and the viability of the synthesized sequences is verified experimentally.
Validation of Solids Suspension Viscosity Measurements Using Computational Fluid Dynamics
Authors: Dasari R. K. , Berson R. E.
Published: January 2011

Accurately measuring the viscosity of a solids suspension requires uniform suspension of the solids in the viscometer cup. In a cup‐and‐impeller viscometer system, solids may settle when the impeller speed is too low, causing viscosity measurements to appear lower than that of a well‐suspended slurry. Pre‐mixing of a solids suspension is typically performed to achieve steady state prior to measurements. Data here shows that the measured viscosity values differ depending on the pre‐mixing speed, indicating that the solids are not properly suspended at all speeds. A commonly used cup‐and‐vane impeller system can be thought of as a mixing tank that should operate above the uniform‐suspension speed (USS), although determining the USS experimentally is rather subjective. Computational fluid dynamics (CFD) is employed here to determine the USS of a pretreated corn stover (PCS) solids suspension and to confirm the experimentally measured USS.
Flow Regime Identification in a Bubble Column via Nuclear Gauge Densitometry and Chaos Analysis
Authors: Nedeltchev S. , Shaikh A. , Al‐Dahhan M.
Published: January 2011

The bubble column performance can change significantly as a result of flow regime change. Since reactor volume productivity, mass and heat transfer as well as mixing are affected by the prevailing flow regime, it is very important to know how to identify it. In this work, flow regime identification was performed on the basis of the Kolmogorov entropy (KE) algorithm applied to nuclear gauge densitometry data. In addition, the average cycle time was used for validation of the results. Three transition velocities were identified that delineated the boundaries of the three main hydrodynamic regimes. The first two transition points were also confirmed by the information entropy concept. The increasing KE trend in the bubbly flow regime and the decreasing KE trend in the churn‐turbulent regime were predicted successfully by means of new semi‐theoretical models.
Deoxygenation of Methanol over ZSM‐5 in a High‐Pressure Catalytic Pyroprobe
Authors: Gunawardena D. A. , Fernando S. D.
Published: January 2011

Deoxygenation is a critical step in making hydrocarbon‐rich biofuels from biomass constituents. Although the thermal effects of oxygenate aromatization have been widely reported, the effect of pressure on this critical reaction has not yet been closely investigated, one primary reason being the unavailability of a reactor that can pyrolyze oxygenates, especially those in solid form, under pressurized conditions. Here, the first of a series of studies on how oxygenates behave when catalytically pyrolyzed under elevated pressure and temperature conditions is reported. Methanol, the simplest alcohol, was selected as the candidate to study the chemical phenomena that occur under pressurized catalytic pyrolysis. The reactions were carried out over the shape‐selective catalyst ZSM‐5 (SiO2/Al2O3 = 30) under varying pressure (0 to 2.0684 MPa (300 psi) in 0.3447 MPa (50 psi) increments) and temperature (500 to 800 °C in 50 °C increments) conditions. Benzene, toluene, ethyl benzene, and xylenes (BTEX) were analyzed as the deoxygenated products of the reaction. The results indicate that the reactor pressure significantly affects deoxygenated product composition.
One‐Photon Photophysics and Two‐Photon Absorption of 4‐[9,9‐Di(2‐ethylhexyl)‐7‐diphenylaminofluoren‐2‐yl]‐2,2′:6′,2′′‐terpyridine and Their Platinum Chloride Complexes
Authors: Ji Zhiqiang , Li Yunjing , Pritchett Timothy M. , Makarov Nikolay S. , Haley Joy E. , Li Zhongjing , Drobizhev Mikhail , Rebane Aleksander , Sun Wenfang
Published: January 2011

The synthesis, one‐photon photophysics and two‐photon absorption (2PA) of three dipolar D‐π‐A 4‐[9,9‐di(2‐ethylhexyl)‐7‐diphenylaminofluoren‐2‐yl]‐2,2′:6′,2′′‐terpyridine and their platinum chloride complexes with different linkers between the donor and acceptor are reported. All ligands exhibit 1π,π* transition in the UV and 1π,π*/1ICT (intramolecular charge transfer) transition in the visible regions, while the complexes display a lower‐energy 1π,π*/1CT (charge transfer) transition in the visible region in addition to the high‐energy 1π,π* transitions. All ligands and the complexes are emissive at room temperature and 77 K, with the emitting excited state assigned as the mixed 1π,π* and 1CT states at RT. Transient absorption from the ligands and the complexes were observed. 2PA was investigated for all ligands and complexes. The two‐photon absorption cross‐sections (σ2) of the complexes (600–2000 GM) measured by Z‐scan experiment are much larger than those of their corresponding ligands measured by the two‐photon induced fluorescence method. The ligand and the complex with the ethynylene linker show much stronger 2PA than those with the vinylene linker.
Surface‐Enhanced Raman Scattering of Single‐ and Few‐Layer Graphene by the Deposition of Gold Nanoparticles
Authors: Lee Jisook , Shim Sangdeok , Kim Bongsoo , Shin Hyeon Suk
Published: January 2011

Surface‐enhanced Raman scattering (SERS) of graphene on a SiO2(300 nm)/Si substrate was investigated by depositing Au nanoparticles using thermal evaporation. This provided a maximum enhancement of 120 times for single‐layer graphene at 633 nm excitation. SERS spectra and scan images of single‐layer and few‐layer graphene were acquired. Single‐layer graphene provides much larger SERS enhancement compared to few‐layer graphene, while in single‐layer graphene the enhancement of the G band was larger than that of the 2D band. Furthermore, the D bands were identified in the SERS spectra; these bands were not observed in a normal Raman spectrum without Au deposition. Appearance of the D band is ascribed to the considerable SERS enhancement and not to an Au deposition‐induced defect. Lastly, SERS enhancement of graphene on a transparent glass substrate was compared with that on the SiO2(300 nm)/Si substrate to exclude enhancement by multiple reflections between the Si substrate and deposited Au nanoparticles. The contribution of multiple reflections to total enhancement on the SiO2(300 nm)/Si substrate was 1.6 times out of average SERS enhancement factor, 71 times.
Magnetoresistance in La0.5Sr0.5MnO2.5
Authors: Cortés‐Gil Raquel , Ruiz‐González M. Luisa , Alonso José M. , García‐Hernández Mar , Hernando Antonio , Vallet‐Regí María , González‐Calbet José M.
Published: January 2011

Resistance measurements indicate the presence of magnetoresistance in the La0.5Sr0.5MnO2.5 brownmillerite related compound. An 80 % of magnetoresistance is found at 75 K. In spite of the partial break‐up occurring at the 3D network of octahedra sharing corners, characteristic of the full oxygen content perovskite phase, the oxygen deficient compound exhibits complex magnetic and electric properties. Such behavior can be explained on the basis of ferromagnetic and metallic clusters randomly distributed at the octahedral layers separated from each other by an insulating antiferromagnetic matrix. AC susceptibility measurements suggest spin glass behavior at low temperature as a consequence of the competition between different magnetic interactions.
Synthesis, Crystal Structures and Magnetic Properties of MIICuII Chains (M=Mn and Co) with Sterically Hindered Alkyl‐Substituted Phenyloxamate Bridging Ligands
Authors: Ferrando‐Soria Jesús , Pardo Emilio , Ruiz‐García Rafael , Cano Joan , Lloret Francisco , Julve Miguel , Journaux Yves , Pasán Jorge , Ruiz‐Pérez Catalina
Published: January 2011

A series of neutral oxamato‐bridged heterobimetallic chains of general formula [MCu(Lx)2(S)2]⋅p S⋅q H2O [p=0–1, q=0–2.5; L1=N‐2,6‐dimethylphenyloxamate, S=DMF with M=Mn (1 a) and Co (1 b); L2=N‐2,6‐diethylphenyloxamate, S=DMF with M=Mn (2 a) and Co (2 b) or S=DMSO with M=Mn (2 c) and Co (2 d); L3=N‐2,6‐diisopropylphenyloxamate, S=DMF with M=Mn (3 a) and Co (3 b) or S=DMSO with M=Mn (3 c) and Co (3 d)] were prepared by treating the corresponding anionic oxamatocopper(II) complexes [Cu(Lx)2]2− (x=1–3) with M2+ cations (M=Mn and Co) in DMF or DMSO as the solvent. The single‐crystal X‐ray structures of 2 a and 3 a reveal the occurrence of well‐isolated, zigzag, oxamato‐bridged manganese(II)–copper(II) chains. The intrachain Cu⋅⋅⋅Mn distances across the oxamato bridge are 5.3761(7) and 5.4002(17) Å for 2 a and 3 a, respectively, whereas the shortest interchain Mn⋅⋅⋅Mn distances are 9.4475(16) and 8.1649(14) Å for 2 a and 3 a, respectively. All of these MIICuII chains (M=Mn and Co) exhibit 1D ferrimagnetic behaviour with moderately strong intrachain antiferromagnetic coupling between the square‐planar CuII and octahedral high‐spin MII ions across the oxamato bridge [−J=31.4–35.2 and 33.4–44.8 cm−1, respectively; H=∑i−JSM,i(SCu,i+SCu,i−1)]. Only the CoIICuII chains show slow magnetic relaxation effects characteristic of single‐chain magnets (SCMs). Analysis of the magnetic relaxation dynamics of 3 d shows a thermally activated mechanism (Arrhenius law dependence) with values of the pre‐exponential factor (τ0=2.6×10−9 s) and activation energy (Ea=7.7 cm−1) that are typical of SCMs. In contrast, two relaxation regimes are observed for 2 d in different temperature regions (τ0=3.2×10−10 s and Ea=24.7 cm−1 for T<4.5 K and τ0=3.2×10−14 s and Ea=37.5 cm−1 for T>4.5 K).
Highly Efficient Multiphoton‐Absorbing Quadrupolar Oligomers for Frequency Upconversion
Authors: Feng Xin Jiang , Wu Po Lam , Li King Fai , Wong Man Shing , Cheah Kok Wai
Published: January 2011

Two series of quadrupolar diphenylamino‐endcapped oligofluorenes, PhN‐OF(n)‐NPh (n=2–5) and PhN‐OF(n)‐TAZ‐OF(n)‐NPh (n=1–4), which have an electron‐withdrawing 1,2,4‐triazole (TAZ) moiety as central core, with D–π–A–π–D structural motif (D=donor, A=acceptor), have been synthesized by palladium‐catalyzed Suzuki cross‐coupling of 9,9‐dibutyl‐7‐(diphenylamino)‐2‐fluorenylboronic acid and the corresponding (1,2,4‐triazole‐based) aryl halide as key step. On pumping with infrared femtosecond lasers, these oligomers showed very strong multiphoton‐excited blue photoluminescence. These D–π–D and D–π–A–π–D quadrupolar oligofluorenes exhibit superior three‐photon absorption properties compared to the respective D–π–A counterparts with a highest three‐photon absorption cross‐section (σ3) of up to 2.72×10−77 cm6 s2. Despite the comparable linear and multiphoton absorption properties of the two types of quadrupolar oligomers PhN‐OF(n)‐NPh and PhN‐OF(n)‐TAZ‐OF(n)‐NPh, only the former exhibit remarkably intense and highly efficient multiphoton‐excited frequency‐upconverted deep blue lasing, which gives rise to record high lasing efficiency of 0.097 % and very narrow of full width at half‐maximum of the lasing spectra. Our findings suggest that quadrupolar‐type molecules/oligomers are superior for multiphoton excited frequency upconverted lasing to their dipolar counterparts and also provide important guidelines to design highly efficient three‐photon absorption molecules for photoluminescence and lasing applications.
Kinetic Studies Exploring the Role of Anion Templation in the Slippage Formation of Rotaxane‐Like Structures
Authors: McConnell Anna J. , Beer Paul D.
Published: January 2011

The first examples of the slippage formation of rotaxane‐like structures in the presence of an anion template are reported between a macrocycle, synthesised by exploiting Eglinton coupling, and stoppered pyridinium axle components. The role of the anion template in the slippage process has been explored by kinetic studies. 1H NMR spectroscopic investigations reveal the slippage species formed are not rotaxanes but pseudorotaxanes with some rotaxane character. The anion template significantly influences the amount of rotaxane character and the rate of slippage. Importantly, the fastest slippage rates, kon, are achieved with the non‐coordinating hexafluorophosphate anion, whereas the slowest slippage off rates, koff, are observed in the presence of coordinating anions, such as chloride. Since the koff rates are significantly smaller than the kon rates in the presence of coordinating anions, these anions act as templates favouring formation of the slippage species thermodynamically. Consequently, the resulting pseudorotaxanes with coordinating anions have greater rotaxane character. Two strategies for converting the slippage pseudorotaxanes into rotaxanes using hydrogenation or complexation with cobalt carbonyl are investigated.
An Efficient Approach for the Characterization of Mucin‐Type Glycopeptides: The Effect of O‐Glycosylation on the Conformation of Synthetic Mucin Peptides
Authors: Hashimoto Ryo , Fujitani Naoki , Takegawa Yasuhiro , Kurogochi Masaki , Matsushita Takahiko , Naruchi Kentaro , Ohyabu Naoki , Hinou Hiroshi , Gao Xiao Dong , Manri Naomi , Satake Hiroyuki , Kaneko Akihito , Sakamoto Takeshi , Nishimura Shin‐Ichiro
Published: January 2011

Despite the growing importance of mucin core O‐glycosylation in many biological processes including the protection of epithelial cell surfaces, the immune response, cell adhesion, inflammation, and tumorigenesis/metastasis, the regulation mechanism and conformational significance of the multiple introduction of α‐GalNAc residues by UDP‐GalNAc:polypeptide N‐acetylgalactosaminyltransferases (ppGalNAcTs) remains unclear. Here we report an efficient approach by combining MS and NMR spectroscopy that allows for the identification of O‐glycosylation site(s) and the effect of O‐glycosylation on the peptide backbone structures during enzymatic mucin domain assembly by using an isoform UDP‐GalNAc:polypeptide N‐acetylgalactosaminyltransferase‐T2 (ppGalNAcT2) in vitro. An electron‐capture dissociation device in a linear radio‐frequency quadrupole ion trap (RFQ‐ECD) combined with a time‐of‐flight (TOF) mass spectrometer was employed for the identification of Thr/Ser residues occupied by α‐GalNAc branching among multiple and potential O‐glycosylation sites in the tandem repeats of human mucin glycoproteins MUC4 (Thr‐Ser‐Ser‐Ala‐Ser‐Thr‐Gly‐His‐Ala‐Thr‐Pro‐Leu‐Pro‐Val‐Thr‐Asp) and MUC5AC (Pro‐Thr‐Thr‐Val‐Gly‐Ser‐Thr‐Thr‐Val‐Gly). In the present study, O‐glycosylation was initiated specifically at Thr10 in naked MUC4 peptide and additional introduction of α‐GalNAc proceeded preferentially but randomly at three other Thr residues to afford densely glycosylated MUC4 containing six α‐GalNAc residues at Thr1, Ser2, Ser5, Thr6, Thr10, and Thr15. On the contrary, O‐glycosylation of naked MUC5AC peptide occurred predominantly at consecutive Thr residues and led to MUC5AC with four α‐GalNAc residues at Thr2, Thr3, Thr7, and Thr8. The solution structures determined by NMR spectroscopic studies elicited that the preferential introduction of α‐GalNAc at Thr10 of MUC4 stabilizes specifically a β‐like extended backbone structure at this area, whereas other synthetic models with a single α‐GalNAc residue at Thr1, Thr6, or Thr15 did not exhibit any converged three‐dimensional structure at the proximal peptide moiety. Such conformational impact on the underlying peptides was proved to be remarkable in the glycosylation at the consecutive Thr residues of MUC5AC.
Starburst Triarylamine Donor–Acceptor–Donor Quadrupolar Derivatives Based on Cyano‐Substituted Diphenylaminestyrylbenzene: Tunable Aggregation‐Induced Emission Colors and Large Two‐Photon Absorption Cross Sections
Authors: Wang Bing , Wang Yaochuan , Hua Jianli , Jiang Yihua , Huang Jinhai , Qian Shixiong , Tian He
Published: January 2011

In this work, we have developed a new class of aggregation‐induced emission (AIE) active compounds, in which three electron‐donating diphenylamine, phenothiazine, or carbazole groups are connected to the 1, 4‐positions of the benzene through bis(α‐cyano‐4‐diphenylaminostyryl) conjugation bridges to form three triarylamine quadrupolar derivatives (3 a–c). Their one‐ and two‐photon absorption properties have been investigated. The two‐photon absorption (2PA) cross sections measured by the open‐aperture Z‐scan technique were determined to be 1016, 1484, and 814 GM for 3 a–c, respectively. From this result, the high 2PA properties of these molecules are attributed to the extended π system and enhanced intramolecular charge transfer from the starburst triarylamine to the cyano group. Moreover, cyano‐substituted diphenylamine styrylbenzene (CNDPASB)‐based compounds are very weakly fluorescent in THF, but their intensities increase by almost 230, 70, and 5 times, respectively, in water/THF (v/v 90 %) mixtures, in which they exhibit strongly enhanced red, orange, and deep yellow fluorescence emissions, respectively. This result indicates that the intramolecular vibration and rotation of these dyes is considerably restricted in nano‐aggregates formed in water, leading to significant increases in fluorescence. It was found that the color tuning of the CNDPASB‐based compounds could be conveniently accomplished by changing the starburst triarylamine donor moiety. Multilayer electroluminescence devices with TPBI (2,2′,2′′‐(benzene‐1,3,5‐triyl)‐tri(1‐phenyl‐1H‐benzimidazole)) electron‐transporting layers have been made, with 3 a and 3 c as a non‐doping red–yellow emitter. The preliminary results for these multilayer devices show a maximum efficiency of 0.25 %, and electroluminescence (EL) wavelengths around 568 nm. The excellent 2PA and AIE properties of these compounds make them potential materials for biophotonic applications.
Neighboring Lithium‐Assisted [1,2]‐Wittig Rearrangement: Practical Access to Diarylmethanol‐Based 1,4‐Diols and Optically Active BINOL Derivatives with Axial and sp3‐Central Chirality
Authors: Gao Guang , Gu Feng‐Lei , Jiang Jian‐Xiong , Jiang Kezhi , Sheng Chun‐Qi , Lai Guo‐Qiao , Xu Li‐Wen
Published: January 2011

A facile and practical methodology for the synthesis of synthetically useful diarylmethanol‐based 1,4‐diols and enantiomerically pure BINOL‐derived diols with axial and sp3‐central chirality has been developed through neighboring lithium‐promoted [1,2]‐Wittig rearrangement. The chirality transfer process shows a broad substrate scope in terms of the aromatic ether substituent, which allows access to a broad of range of chiral 1,1′‐binaphthalene‐2‐α‐arylmethanol‐2′‐ols with excellent enantioselectivities (>99 % enantiomeric excess) and yields (84–96 %). This should be considered as an available and attractive chiral source to design and prepare privileged ligands or catalysts.
One‐Pot Selective Syntheses of 5‐Azaindoles through Zirconocene‐Mediated Multicomponent Reactions with Three Different Nitrile Components and One Alkyne Component
Authors: Zhang Shaoguang , Zhang Wen‐Xiong , Zhao Jing , Xi Zhenfeng
Published: January 2011

5‐Azaindoles either with three different substituents at their 2‐, 4‐, and 6‐positions or with two identical substituents at their 2‐ and 6‐positions and a different one at the 4‐position, were obtained in good to excellent isolated yields by a zirconocene‐mediated multicomponent process. Each reaction involved four organic partners, comprising a Si‐tethered diyne, one tBuCN component, and two (either different or identical) nitriles. All these four components were combined through the action of a Cp2ZrII species into a three‐ring fused Zr/Si‐containing organometallic complex in a perfectly chemo‐ and regioselective manner. This multicomponent reaction process consisted of three reaction steps, all of which were made clear through the isolation and characterization of their corresponding organometallic intermediates: the zirconacyclopropene‐azasilacyclopentadienes 2, the allenyl‐aza‐zirconacycles 3, and the three‐ring fused complexes 6. X‐ray single‐crystal structural analyses of two three‐ring fused Zr/Si‐containing intermediates and two 5‐azaindoles unambiguously showed the positions of the different substituents and the regioselectivity. Iminopyrrole derivatives could be also highly selectively prepared from a Si‐tethered diyne and two different nitriles.
The safety and efficacy of high‐dose proton beam radiotherapy for hepatocellular carcinoma: a phase 2 prospective trial
Authors: Bush David A. , Kayali Zeid , Grove Roger , Slater Jerry D.
Published: January 2011

BACKGROUND:

Proton beam therapy (PBT) may provide useful local‐regional treatment for hepatocellular carcinoma (HCC). The purpose of this study was to evaluate the safety and efficacy of PBT for HCC.

METHODS:

Patients with cirrhosis who had radiological features or biopsy‐proven HCC were included in the study. Patients without cirrhosis and patients with extrahepatic metastasis were excluded. The mean age was 62.7 years. The mean tumor size was 5.5 cm. Eleven patients had multiple tumors, and 46% were within the Milan criteria. Patients received 63 Gy delivered over a 3‐week period with PBT.

RESULTS:

Seventy‐six patients were treated and followed prospectively for treatment outcomes at Loma Linda University Medical Center. Acute toxicity was minimal; all patients completed the full course of treatment. Radiation‐induced liver disease was evaluated using liver enzyme, bilirubin, and albumin levels; no significant change supervened 6 months posttreatment. Median progression‐free survival for the entire group was 36 months, with a 60% 3‐year progression‐free survival rate for patients within the Milan criteria. Eighteen patients subsequently underwent liver transplantation; 6 (33%) explants showed pathological complete response and 7 (39%) showed only microscopic residual.

CONCLUSIONS:

PBT was found to be a safe and effective local‐regional therapy for inoperable HCC. A randomized controlled trial to compare its efficacy to a standard therapy has been initiated. Cancer 2011. © 2011 American Cancer Society.
Early findings on toxicity of proton beam therapy with concurrent chemotherapy for nonsmall cell lung cancer
Authors: Sejpal Samir , Komaki Ritsuko , Tsao Anne , Chang Joe Y. , Liao Zhongxing , Wei Xiong , Allen Pamela K. , Lu Charles , Gillin Michael , Cox James D
Published: January 2011

BACKGROUND:

Concurrent chemoradiation therapy, the standard of care for locally advanced nonsmall cell lung cancer (NSCLC), can cause life‐threatening pneumonitis and esophagitis. X‐ray (photon)‐based radiation therapy (RT) often cannot be given at tumoricidal doses without toxicity to proximal normal tissues. We hypothesized that proton beam therapy for most patients with NSCLC could permit higher tumor doses with less normal‐tissue toxicity than photon RT delivered as 3‐dimensional conformal RT (3D‐CRT) or intensity‐modulated RT (IMRT).

METHODS:

We compared the toxicity of proton therapy+concurrent chemotherapy in 62 patients with NSCLC (treatment period 2006‐2008) with toxicity for patients with similar disease given 3D‐CRT+chemotherapy (n = 74; treatment period 2001‐2003) or IMRT+chemotherapy (n = 66; treatment period 2003‐2005). Proton therapy to the gross tumor volume was given with weekly intravenous paclitaxel (50 mg/m2) and carboplatin (area under the curve 2 mg/mL/min). The primary endpoint was toxicity (Common Terminology Criteria for Adverse Events version 3.0).

RESULTS:

Median follow‐up times were 15.2 months (proton), 17.9 months (3D‐CRT), and 17.4 months (IMRT). Median total radiation dose was 74 Gy(RBE) for the proton group versus 63 Gy for the other groups. Rates of severe (grade ≥3) pneumonitis and esophagitis in the proton group (2% and 5%) were lower despite the higher radiation dose (3D‐CRT, 30% and 18%; IMRT, 9% and 44%; P<.001 for all).

CONCLUSIONS:

We found that higher doses of proton radiation could be delivered to lung tumors with a lower risk of esophagitis and pneumonitis. A randomized comparison of IMRT versus proton therapy is underway. Cancer 2011. © 2011 American Cancer Society.
Local control comparison of adjuvant brachytherapy to intensity‐modulated radiotherapy in primary high‐grade sarcoma of the extremity
Authors: Alektiar Kaled M. , Brennan Murray F. , Singer Samuel
Published: January 2011

BACKGROUND:

Based on results of a prospective randomized trial, brachytherapy (BRT) had been the preferred form of adjuvant radiotherapy for patients with high‐grade extremity soft tissue sarcoma (STS) at our institution. In recent years, intensity‐modulated radiotherapy IMRT had been increasingly used. This study compared local control by IMRT versus by BRT in primary‐extremity STS.

METHODS:

Between January 1995 and December 2006, 134 adult patients with high‐grade primary nonmetastatic STS of the extremity were treated at this institution with limb‐sparing surgery and adjuvant radiotherapy (RT). Low‐dose‐rate BRT was given to 71 patients between January 1995 and November 2003 to a median dose of 45 Gray (Gy). IMRT was given between February 2002 and December 2006: preoperatively to 10 (50 Gy) and postoperatively to 53 (median, 63 Gy). Median follow‐up was 46 months.

RESULTS:

Treatment groups were comparable in terms of gender, age, site, depth, histology (malignant fibrous histiocytoma vs other), and use of adjuvant chemotherapy. More IMRT patients had positive/close margins (<1 mm), large tumors (>10 cm), and bone or nerve stripping/resection (P= 0.006, 0.005, 0.02, and 0.002, respectively). Median follow‐up was 46 months for IMRT and 47 months for BRT. Five‐year local control was 92% (95% confidence interval [CI], 85‐100) for IMRT versus 81% (95% CI, 71‐90) for BRT,P= 0.04. On multivariate analysis, IMRT was the only predictor of improved local control,P= 0.04.

CONCLUSIONS:

Local control with IMRT was significantly better than BRT despite higher rates of adverse features for IMRT in this nonrandomized comparison. IMRT should be further examined as the treatment of choice for primary high‐grade extremity sarcoma. Cancer 2011. © 2011 American Cancer Society.
Diagnosis and management of dysplasia and cancer of the ileal pouch in patients with underlying inflammatory bowel disease
Authors: Liu Zhao‐xiu , Kiran Ravi P. , Bennett Ana E. , Ni Run‐zhou , Shen Bo
Published: January 2011

Approximately 30% of the patients with ulcerative colitis (UC) would ultimately require colectomy for medically refractory UC or UC‐associated neoplasia. Restorative proctocolectomy with ileal pouch‐anal anastomosis has become the surgical treatment of choice for these patients. However, this procedure does not completely abolish the risk for neoplasia of the pouch. The main risk factor for pouch neoplasia is a preoperative diagnosis of UC‐associated dysplasia or cancer. Although the natural history and prognosis of pouch dysplasia are not clear, mortality associated with pouch cancer, once diagnosed, appears to be high. Conversely, not all pouch neoplasia follows the chronic inflammation‐dysplasia‐cancer sequence, which makes pouch endoscopy with biopsy, the current gold standard for surveillance, challenging. In addition, the findings that pouch neoplasia is not common and that pouch endoscopy still misses dysplasia lead to controversy on the need and time interval of routine endoscopic surveillance. However, based on reports in the literature and their own experience, the authors recommend surveillance endoscopy to be performed in patients at risk, such as those with a precolectomy diagnosis of UC‐associated neoplasia. This review appraises issues in the prevalence and incidence, risk factors, technical aspects of pouch construction, clinical and pathological features, natural history, surveillance examination, diagnosis, and management of pouch neoplasia. Cancer 2011. © 2011 American Cancer Society.
Rhabdomyosarcoma in infants younger than 1 year
Authors: Malempati Suman , Rodeberg David A. , Donaldson Sarah S. , Lyden Elizabeth R. , Anderson James R. , Hawkins Douglas S. , Arndt Carola A. S.
Published: January 2011

BACKGROUND:

Rhabdomyosarcoma (RMS), the most common soft‐tissue sarcoma in children, occurs less commonly in infants. Historically, poorer outcomes have been reported for infants diagnosed with RMS than for older children.

METHODS:

The authors analyzed the characteristics, treatment administered, outcomes, and patterns of failure for infants aged < 1 year with nonmetastatic RMS who received multimodal therapy on Intergroup Rhabdomyosarcoma Study (IRS) protocols IRS‐IV, D9602, and D9803.

RESULTS:

Seventy‐six infants with nonmetastatic RMS were treated on the 3 protocols from 1991 to 2005. Their median age was 7.4 months (range, 0.1‐12 months). Tumor histology included embryonal (57%), alveolar (21%), and undifferentiated sarcoma/other (22%). A parameningeal primary tumor site was less common in this infant cohort (3%) than in all patients who were treated on IRS‐IV (25%). The estimated 5‐year failure‐free survival and overall survival rates (95% confidence interval [CI]) were 57% (95% CI, 44%‐67%) and 76% (95% CI, 65%‐85%), respectively, for infants compared with 81% (95% CI, 79%‐83%) and 87% (95% CI, 85%‐89%), respectively, for children ages 1 to 9 years. Twenty‐three of 32 infants with treatment failure had local recurrence/progression with distant failure (n = 3) or without distant failure (n = 20). The overall local failure rate was 30%. The median time to treatment failure was 13 months. The failure‐free survival rate was worse for infants who had IRS Group III tumors and for those who received less than protocol‐recommended radiation therapy.

CONCLUSIONS:

Infants with RMS appeared to have worse outcomes than older patients, in part because of high rates of local failure. The authors concluded that concerns regarding morbidity in infants and reluctance to use aggressive local control measures may lead to higher rates of local failure. Cancer 2011. © 2011 American Cancer Society.
A novel exon 15‐deleted, splicing variant of Slit2 shows potential for growth inhibition in addition to invasion inhibition in lung cancer
Authors: Lin Yu‐Ying , Yang Chun‐Hung , Sheu Gwo‐Tarng , Huang Chi‐Ying F. , Wu Yu‐Chung , Chuang Shu‐Ming , Fann Ming‐Ji , Chang Han , Lee Huei , Chang Jinghua Tsai
Published: January 2011

BACKGROUND:

The axon guidance cue molecule Slit2 has been shown to suppress cancer cell invasion. However, the role of Slit2 in growth inhibition is still controversial. The authors identified a novel exon 15 (AKEQYFIP)‐deleted slit2, located at the end of the second leucine‐rich repeat (LRR2). Because LRR2 interacts with Robo1 receptor to inhibit invasion, they hypothesized that exon 15 plays an important role in modulating Slit2 function.

METHODS:

Slit2 expression was assessed via microarray analysis in 27 lung adenocarcinomas. Exon 15‐deleted slit2 (slit2‐ΔE15) and exon 15‐containing slit2 (slit2‐WT) were cloned and expressed in the CL1‐5 lung cancer cell line. The effect of exon 15 on Slit2‐mediated cell growth was evaluated by a xenografted model and in vitro cell growth assays. The effect of exon 15 on Slit2‐mediated invasion was analyzed with a modified Boyden chamber in vitro.

RESULTS:

Tumor growth from CL1‐5/Slit2‐WT cells was comparable to that from CL1‐5 cells bearing empty vector. However, tumor size from CL1‐5/Slit2‐ΔE15 cells was much smaller than that from Slit2‐WT cells or vector control cells in the xenografted model. In vitro analyses demonstrated that Slit2‐WT inhibits invasion of CL1‐5 cells. In addition to inhibiting invasion, Slit2‐ΔE15 greatly suppresses cell growth.

CONCLUSIONS:

The data demonstrated that exon 15 modulates Slit2 function in growth inhibition of lung cancer cells. Because slit2‐ΔE15 splice variant is present in low invasive cancer cells and nontumor lung tissues, loss of this splice variant is an important event in tumor progression and invasion. Cancer 2011. © 2011 American Cancer Society.
Independent and tissue‐specific prognostic impact of miR‐126 in nonsmall cell lung cancer
Authors: Donnem Tom , Lonvik Kenneth , Eklo Katrine , Berg Thomas , Sorbye Sveinung W. , Al‐Shibli Khalid , Al‐Saad Samer , Andersen Sigve , Stenvold Helge , Bremnes Roy M. , Busund Lill‐Tove
Published: January 2011

BACKGROUND:

Angiogenesis is pivotal in tumor development. Vascular endothelial growth factor‐A (VEGF‐A) is considered one of the most important angiogenic factors, but lately several microRNAs (miRs) have been associated with vascular development. miR‐126 has been related to tumor angiogenesis and in the regulation of VEGF‐A. The authors aimed to investigate the prognostic impact of miR‐126 and its co‐expression with VEGF‐A in nonsmall cell lung cancer (NSCLC) patients.

METHODS:

Tumor tissue samples from 335 resected stage I to IIIA NSCLC patients were obtained and tissue microarrays (TMAs) were constructed with 4 cores from each tumor specimen. VEGF‐A expression was evaluated by immunohistochemistry, and in situ hybridization was used to evaluate the expression of miR‐126.

RESULTS:

In the total material, miR‐126 was a significant negative prognostic factor in both univariate (P = .005) and multivariate analyses (hazard ratio [HR] 1.8, 95% confidence interval [CI] 1.2‐2.8, P = .01). Stratified by histology, miR‐126 was only significant in squamous cell carcinomas (univariate: P < .001; multivariate: HR 3.1, CI 95% 1.7‐5.6, P<.001). Stratified by lymph node status, miR‐126 was significant only in the lymph node‐positive subgroup (univariate: P<.001; multivariate: HR 4.1, CI 95% 2.0‐8.4, P < .001). High miR‐126 expression correlated significantly with high VEGF‐A expression (P = .037). The co‐expression of miR‐126 and VEGF‐A had a significant prognostic impact (P = .002), with 5‐year survival rates of 68%, 51%, and 42% for low/low (n = 150), mixed combinations (n = 129), and high/high (n = 35) expression, respectively.

CONCLUSIONS:

miR‐126 is a strong and independent negative prognostic factor in NSCLC, and its prognostic impact appears related primarily to histology and nodal status. Cancer 2011. © 2011 American Cancer Society.
Temperature quenching of photoluminescence of ordered GaInP2 alloy under different excitation densities
Authors: Prutskij T. , Pelosi C. , Attolini G.
Published: January 2011

The photoluminescence (PL) emission from an epi‐structure containing an atomically ordered GaInP2 layer and a GaAs layer was studied under excitation power densities of 0.03 – 3 W/cm2at temperatures of 10 to 300 K. The quenching of the integrated PL intensity from both: the GaInP2and the GaAs layers is stronger under low excitation, than under high excitation density. The temperature dependence, however, have different shapes being the PL decay observed for the GaInP2 layer stronger than that for the GaAs layer. Comparing the temperature dependence of the PL intensity from the ordered GaInP2 and the GaAs layers under different excitation densities and analyzing them together, we conclude that the inhomogeneity of the ordered layer is responsible for the different temperature behavior of the GaInP2 alloy PL emission. To explain the experimentally observed PL intensity temperature dependence an additional nonradiative recombination mechanism due to a thermally activated escape of the carriers from its confinement within regions of lower bandgap has to be taken into account. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Harmonic balance‐based control of a boost DC/AC converter
Authors: Olm Josep M. , Biel Domingo , Spinetti‐Rivera Mario , Fossas Enric
Published: January 2011

The achievement of step‐up inversion with a boost DC/AC converter requires appropriate periodic references for inductor currents, which have to satisfy ordinary differential equations (ODE) of the Abel type. These are equations with highly unstable solutions for which the existence of periodic solutions remains unproved. Hence, the studies reported so far in this subject obtain periodic output voltages that approximately track the expected profile using different periodic current references that do not exactly satisfy the Abel ODE. However, neither an explanation of why are periodic output voltages still obtained, nor an assessment of the output voltage error is provided. This paper analyzes the effect of using periodic current references in a Lyapunov‐based controlled boost DC/AC converter performing step‐up inversion tasks. It is shown that, for sufficiently accurate current references, the system exhibits asymptotically stable periodic solutions with bounded error. Moreover, the paper propounds the use of Harmonic Balance (HB)‐based techniques to obtain such current references. Simulation and experimental results confirm that this choice yields periodic output voltages with an error that may be lowered using higher HB approximations. Copyright © 2011 John Wiley & Sons, Ltd.
Parallel and Gaussian frequency hopping for dynamic coexistence in the unlicensed band
Authors: Hasan M. M. , Prakash Ravi , Jue Jason P.
Published: January 2011

With the surge of short‐range wireless applications, more networks are being deployed in the unlicensed radio band. The challenge that emerges is to accommodate these networks without breaching current rules and regulations on frequency usage. This paper studies the coexistence of several independent and dynamic wireless networks using the frequency hopping technique. We propose a novel hopping scheme that minimizes mutual interference and allows more networks to collocate effectively, but does not violate restrictions imposed by the Federal Communications Commission (FCC) regarding frequency constraint (related to the minimum number of frequencies in a hopping set) and time constraint (related to the maximum duration of using a particular frequency). The coexisting networks follow the Gaussian distribution in choosing transmission frequencies from parallel hopping spaces without the overhead of extra message exchange among networks. Simulation results on key metrics such as channel collision rate, goodput, and fairness in channel usage are presented to establish the viability of the proposed scheme in comparison with other contemporary approaches. Copyright © 2011 John Wiley & Sons, Ltd.
Color recognition with compact color features
Authors: Park Sun‐Mi , Kim Ku‐Jin
Published: January 2011

For color images, color histograms are generally used as the color feature vectors for classifying the colors of objects. To achieve a higher success rate in color classification, feature vectors with a higher dimension are required, yet this causes a low efficiency with regard to the computation time and memory usage. Therefore, this paper proposes a method of reducing the feature vector dimension by a factor of 170 based on combining two techniques: (i) projecting a color histogram generated in 3D color space into 2D color planes and (ii) converting the color histograms to class histograms using a naive Bayesian classifier. The resulting feature vectors are then classified using a support vector machine method and template matching method to recognize the object colors. With both classification methods, a better recognition rate is achieved than when using the original large feature vectors. Copyright © 2011 John Wiley & Sons, Ltd.
Initial value compensation with additional input considering optimization of control input
Authors: Hirose Noriaki , Terachi Yasuhisa , Kawafuku Motohiro , Iwasaki Makoto , Hirai Hiromu
Published: January 2011

This paper presents a novel method of initial value compensation (IVC) with additional input by considering the optimization of control input. IVC has been used to improve the control performance of various control systems with different initial values. Essential subjects, however, have still remained: in the conventional IVC approaches, the increases in the amplitude and number of high‐frequency components of the control input that accompany an increase in the control bandwidth could not be avoided. In this research, therefore, an optimization approach for control input is applied under the constraints of the conventional IVC approach. The effectiveness of the proposed approach has been verified by numerical simulations and experiments using a prototype. © 2011 Wiley Periodicals, Inc. Electr Eng Jpn, 175(2): 63‐73, 2011; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.21026
Characteristics of supersonic closed loop with disk CCMHD generator
Authors: Yamasaki Hiroyuki , Murakami Tomoyuki , Okuno Yoshihiro
Published: January 2011

The results of an experimental study on performance of a supersonic closed loop with a disk MHD generator are described. High‐temperature (>1900 K) argon circulation was carried out successfully for 2.4 hours. The heat gain and loss of argon was investigated, and a large heat loss was found at the diffuser and the exhaust duct, although the energy efficiency of the recuperator was high. The large heat loss was ascribed to water cooling at the diffuser and the exhaust duct. At the same time, enhancement of the heat transfer coefficient was suggested. The argon temperature and the heat loss calculated under the assumption of a heat transfer coefficient four times as large show good agreement with experimental data. The pressure ratio inside the loop was investigated, and the results indicate that the total pressure upstream of the nozzle throat is decided by the total temperature and the mass flow. On the other hand, the total pressure on the downstream side is determined by the total mass in the loop and the total pressure on the upstream side. The first power generation was carried out, and a good correlation between the load resistance and the Hall voltage was observed. However, the power output remained very small. © 2011 Wiley Periodicals, Inc. Electr Eng Jpn, 175(2): 1–12, 2011; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.21069
A transient chaotic associative memory model with temporary stay function
Authors: Obayashi Masanao , Narita Kenichiro , Kobayashi Kunikazu , Kuremoto Takashi
Published: January 2011

When chaotic dynamics is imparted to the neurons that compose the associative memory model, they search for stored patterns in a pattern space chaotically. However, this model has the deficiency that judgment of whether the stored pattern has been recollected or not is difficult because its behavior is always chaotic. Because all dynamics of the chaotic neurons are chaotic, chaotic transition is repeated. The transient‐chaotic associative network (TCAN) that Lee proposed changes from the state of chaos to the state of stability (nonchaos) transiently. Additionally, it has fast recollection speed, and has large memory capacity. However, the states of TCAN do not change chaotically. Based on these results, this paper proposes a transient chaotic associative memory model with a temporary stay function (TCAMMwithTSF) which has two capabilities: one is fast speed as the states of the model converge to a stored pattern, like TCAN, and the other is the ability to search the stored pattern in a pattern space chaotically, like chaotic neural networks. Finally, the characteristics and usefulness of TCAMMwithTSF are verified by a simulation study. © 2011 Wiley Periodicals, Inc. Electr Eng Jpn, 175(2): 29–36, 2011; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.21077
Feedforward compensation by specified step settling considering frequency shaping of control input
Authors: Hirose Noriaki , Kawafuku Motohiro , Iwasaki Makoto , Hirai Hiromu
Published: January 2011

This paper presents a novel feedforward compensation for the fast and precise positioning control in mechatronic systems. The proposed compensator is designed considering the frequency shaping in control input to suppress the residual vibration, under the constraint of a specified number of steps in position reference. A two‐degree‐of‐freedom positioning controller with the proposed feedforward compensation can ensure the required settling performance with the specified number of steps regardless of the positioning amplitude in reference. The effectiveness of the proposed approach has been verified by numerical simulations and experiments using a prototype of galvano scanner. © 2011 Wiley Periodicals, Inc. Electr Eng Jpn, 175(2): 54–62, 2011; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.21084
Effect of increased charring on the narrow side of rectangular timber cross‐sections exposed to fire on three or four sides
Authors: Frangi Andrea , König Jürgen
Published: January 2011

Owing to the influence of two‐dimensional heat transfer, fire tests and heat transfer calculations show that charring on the narrow side of rectangular timber cross‐sections may be considerably greater than charring on the wide side. For timber members unprotected throughout the time of fire exposure as well as members initially protected from fire exposure, it is shown by calculation, that the relationship between charring on the narrow side and time is nonlinear. In order to take into account increased charring on the narrow side of timber members a section factor ks was determined. By calculation it is shown that bending moment resistance is only insignificantly influenced by the effect of two‐dimensional heat transfer and the factor ks can therefore be neglected, making the fire design of timber members easier. Copyright © 2011 John Wiley & Sons, Ltd.
Essay review: Writing about geology
Authors: Donovan Stephen K.
Published: January 2011

Geologists need to write and publish, but completing a Ph.D. is not the same as taking a writing course for academic authors. Writing for publication is a core academic task; only when a discovery has been published does it enter the consciousness of geology. But a geologist must learn how to write by practice. Writing about Archaeology by Graham Connah examines the basics of academic authorship in terms that are broadly applicable to geology, too. Good authors in geology are made, not born. Copyright © 2011 John Wiley & Sons, Ltd.