bluuebunny/crossref_metadata_2025 huggingface dataset:
“intelligent” polymers in medicine and biotechnology
Authors: Hoffman Allan S.
Published: March 2011

One can define “intelligent” polymers as those polymers which respond with large property changes to small physical or chemical stimuli. These polymers may be in various forms, such as in solution, on surfaces, or as solids. One may also combine “intelligent” aqueous polymer systems with biomolecules, to yield a large family of polymers which respond “intelligently” to physical, chemical or biological stimuli. This article overviews such interesting and versatile polymer systems.
Organic/inorganic polymer hybrids
Authors: Saegusa Takeo
Published: March 2011

A series of new materials, organic/inorganic polymer hybrids, are described, which are blends of molecular level dispersion between an organic polymer and a metal oxide such as silica. The new materials are transparent glassy solids, which are prepared by the sol‐gel reaction of a metal alkoxide in the presence of an organic polymer whose repeating unit contains carboxylic amide group. The structure of a molecular level dispersion has been disclosed by AFM, pore size distribution and surface measurements. The structure of interpenetrating network is realized by the hydrogen bonding between metal‐OH group (H‐donor) in the sol‐gel intermediate species and amide group (H‐acceptor) of polymer components. Preparative method, structural characteristics, scope and variations, and possible applications of these new materials are described.
On the scope and interpretation of the Tofts models for DCE‐MRI
Authors: Sourbron Steven P. , Buckley David L.
Published: March 2011

The Tofts model (TM) and extended Tofts model (ETM) have become a standard for the analysis of dynamic contrast‐enhanced MRI. In this study, a mathematical analysis is used to identify exactly in which tissue types the Tofts models may be applied. The results show that the TM is accurate if and only if the tissue is weakly vascularised (small blood volume). The ETM is additionally accurate in highly perfused tissues (high blood flow). In tissues that are highly vascularised, or where tracer exchange is very fast or very slow, TM and ETM accurately fit the data but lead to a misinterpretation of the parameters. In tissue types with intermediate vascularity, perfusion and tracer exchange, neither model offers a good fit to the tissue concentrations. A good fit can be obtained with a measured input function by reducing the temporal resolution, but this does not improve the accuracy of the parameters. In conclusion, the Tofts models only produce reliable parameter values if the tissue is weakly vascularized (TM or ETM) or highly perfused (ETM). Without prior knowledge that at least one of these constraints is fulfilled, the physiological interpretation of the values produced by the Tofts models is unclear. Magn Reson Med, 2011. © 2011 Wiley‐Liss, Inc.
Somatic mutation of fibroblast growth factor receptor‐3 (FGFR3) defines a distinct morphological subtype of high‐grade urothelial carcinoma
Authors: Al‐Ahmadie Hikmat A , Iyer Gopa , Janakiraman Manickam , Lin Oscar , Heguy Adriana , Tickoo Satish K. , Fine Samson W. , Gopalan Anuradha , Chen Ying‐bei , Balar Arjun , Riches Jamie , Bochner Bernard , Dalbagni Guido , Bajorin Dean F. , Reuter Victor E. , Milowsky Matthew I. , Solit David B.
Published: March 2011

FGFR3 mutations are common in low‐grade urothelial carcinoma and represent a potential therapeutic target in this disease. Their incidence and functional role in high‐grade urothelial carcinoma (HGUC), which displays an increased propensity for recurrence and muscularis propria invasion, is less well defined. We developed a mass spectrometry‐based genotyping assay to define the incidence of FGFR3 mutations in a large clinically annotated set of urothelial carcinomas. FGFR3 mutations were found in 17% of HGUC versus 84% of low‐grade lesions. Retrospective pathological review of the class of FGFR3 mutant HGUC revealed unique histological features, characterized by a bulky, exophytic component with branching papillary architecture as well as irregular nuclei with a koilocytoid appearance. The predictive value of this histological appearance was confirmed using a prospective set of 49 additional HGUCs. Prospective histological review was able to correctly predict for the presence of an FGFR3 mutation in 13/24 HGUC specimens that exhibited the distinct morphology (54%). All 25 specimens lacking the defined histological features were FGFR3 wild‐type for a negative predictive value of 100%. Macrodissection of individual tumours confirmed the presence of the FGFR3 mutant allele in non‐invasive and invasive, low and high‐grade regions of individual tumours and in the lymph node metastases of patients whose tumours possessed the characteristic morphological signature, suggesting that FGFR3 mutations are not restricted to the more clinically indolent regions of HGUCs. These data suggest that histological screening of HGUCs followed by confirmatory genotyping can be used to enrich for the population of HGUCs most likely to harbour activating mutations in the FGFR‐3 receptor tyrosine kinase. Histological review could thus aid in the development of targeted inhibitors of FGFR‐3 by facilitating the identification of the subset of patients most likely to harbour activating mutations in the FGFR3 gene. Copyright © 2011 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Bereaved parental evaluation of the quality of a palliative care program in Lebanon
Authors: Saad Rima , Huijer Huda Abu‐Saad , Noureddine Samar , Muwakkit Samar , Saab Raya , Abboud Miguel R.
Published: March 2011

Background

Palliative care (PC) is important in Pediatric Oncology as more than 20% of children with cancer still die despite modern treatment. As a significant number of children reside in countries with limited resources; more research in PC is needed there. This study aimed at evaluating the quality of care provided to children with cancer at the Children's Cancer Center of Lebanon (CCCL) during their last month of life as perceived by the bereaved parents.

Procedure

Between 2002 and 2007, 76 children with cancer treated at CCCL succumbed to their disease. Twenty‐nine of the bereaved parents were interviewed at home about the symptoms and suffering experienced by their children during the last month of life, communication with the healthcare team, quality of care delivered, and recommendations for improving care.

Results

Fatigue, anorexia, and pain were the most prevalent symptoms and edema was the most distressing. The overall communication with the healthcare team and the overall quality of care delivered was rated as “very good” to “excellent” by 86.2% and 93.1% of the participants, respectively. Parents suggested improving the organization of care, the communication, and the availability of human and material resources.

Conclusions

This study is the first conducted in Lebanon to evaluate the quality of pediatric palliative care (PPC). The parents' experiences in our country were similar to those described in other countries, religions, and cultures. Significant strengths and weaknesses in the management of the dying children, from the parents' perspective, were uncovered and recommendations for improving practice were made. Pediatr Blood Cancer 2011; 57: 310–316. © 2011 Wiley‐Liss, Inc.
Correlation analysis of epoxy/amine resin cure, structure and chemorheological behavior in RTM processes
Authors: Ding Yanyu , Jia Yuxi , Yang Junying , He Haidong , Sun Sheng , Shi Tongfei
Published: March 2011

At the reactive mould‐filling stage in resin transfer moulding (RTM) processes, the correlation analysis of epoxy/amine resin cure, structure and chemorheological behavior plays a key role in the optimum control of RTM processes. A new methodology used to simulate the reactive resin flow in RTM processes with edge effect is presented in this article. The recursive approach and the branching theory are used to describe the evolution of molecular structure and resin viscosity, respectively. And then the resin flow process is simulated by means of a semi‐implicit iterative calculation method and the finite volume method. The results reveal the proposed resin cure‐structure‐viscosity model provides excellent agreement with the experimental viscosity data during the RTM filling process. It is also observed that the curing reaction causes the inhomogeneous distribution of resin conversion and resin molecular weight in the mould cavity, which will result in the spatially structural and performance inhomogeneities in the finished products. With the injection temperature or the edge width increasing, the discrepancy of resin conversion and resin molecular weight in the mould cavity is more evident. This study is helpful for understanding the complicated relationship among the processing variables, resin structures, and properties. POLYM. COMPOS., 2011. © 2011 Society of Plastics Engineers
Characterization of fetal cardiac structure and function detected by echocardiography in women with normal pregnancy and gestational diabetes mellitus
Authors: Ren Yunyun , Zhou Qiongjie , Yan Yingliu , Chu Chen , Gui Yonghao , Li Xiaotian
Published: March 2011

Objectives

To assess fetal cardiac structure and function in normal pregnancy and in the presence of gestational diabetes mellitus (GDM) using echocardiography measurements.

Material and methods

We studied fetal cardiac structure and function in 169 uncomplicated singleton pregnancies and in 92 complicated by GDM. Maternal glycemic control was deemed adequate in 75 women and inadequate in 17. Fetal two‐dimensional ultrasound, pulsed wave Doppler and tissue Doppler imaging (TDI) were used to assess cardiac walls thickness and cardiac function, both systolic [with ejection fraction (EF)] and diastolic [using early diastolic peak flow velocity (E)/late peak of diastolic velocity (A) and early diastolic peak velocity at the annulus (Ea)/late diastolic peak velocity at the annulus (Aa) ratios].

Results

In normal pregnancies, fetal ventricular walls and interventricular septum thickness increased progressively with advancing gestation and were significantly thicker in the presence of GDM (P < 0.001) independently of maternal glycemic control. Fetal cardiac systolic function indicated by EF did not change during normal pregnancy, but was significantly increased (P < 0.001) in the presence of GDM independently of maternal glycemic control. Both pulsed wave Doppler and TDI indicators of fetal diastolic cardiac function increased during normal pregnancy, reaching a maximum at 36 to 40 weeks of gestation (P < 0.001). The presence of GDM did not affect pulsed wave Doppler indicators of diastolic function [ratio of early/late diastolic peak flow velocity (E/A ratio)], whereas TDI indices [ratio of early/late diastolic peak velocity at the annulus (Ea/Aa ratio)] were significantly lower after adjustment for gestational age and estimated fetal weight (EFW); and such changes were independent of maternal diabetic control (P < 0.001).

Conclusions

Fetal cardiac wall thickness, cardiac systolic and diastolic functions are affected by GDM independently of glycemic control. Copyright © 2011 John Wiley & Sons, Ltd.
Molecular interactions between wheat and cereal aphid (Sitobion avenae): Analysis of changes to the wheat proteome
Authors: Ferry Natalie , Stavroulakis Stylianos , Guan Wenzhu , Davison Gillian M. , Bell Howard A. , Weaver Robert J. , Down Rachel E. , Gatehouse John A. , Gatehouse Angharad M. R.
Published: March 2011

Aphids are major insect pests of cereal crops, acting as virus vectors as well as causing direct damage. The responses of wheat to infestation by cereal aphid (Sitobion avenae) were investigated in a proteomic analysis. Approximately, 500 protein spots were reproducibly detected in the extracts from leaves of wheat seedlings after extraction and 2‐DE. Sixty‐seven spots differed significantly between control and infested plants following 24 h of aphid feeding, with 27 and 11 up‐regulated, and 8 and 21 down‐regulated, in local or systemic tissues, respectively. After 8 days, 80 protein spots differed significantly between control and aphid treatments with 13 and 18 up‐regulated and 27 and 22 down‐regulated in local or systemic tissues, respectively. As positive controls, plants were treated with salicylic acid or methyl jasmonate; 81 and 37 differentially expressed protein spots, respectively, were identified for these treatments. Approximately, 50% of differentially expressed protein spots were identified by PMF, revealing that the majority of proteins altered by aphid infestation were involved in metabolic processes and photosynthesis. Other proteins identified were involved in signal transduction, stress and defence, antioxidant activity, regulatory processes, and hormone responses. Responses to aphid attack at the proteome level were broadly similar to basal non‐specific defence and stress responses in wheat, with evidence of down‐regulation of insect‐specific defence mechanisms, in agreement with the observed lack of aphid resistance in commercial wheat lines.
Comparative proteomic profiles of the soybean (Glycine max) root apex and differentiated root zone
Authors: Mathesius Ulrike , Djordjevic Michael A. , Oakes Marie , Goffard Nicolas , Haerizadeh Farzad , Weiller Georg F. , Singh Mohan B. , Bhalla Prem L.
Published: March 2011

The root apical meristem (RAM) is responsible for the growth of the plant root system. Because of the importance of root architecture in the performance of crop plants, we established a proteome reference map of the soybean root apex and compared this with the proteome of the differentiated root zone. The root apex samples contained the apical 1 mm of the root, comprising the RAM, quiescent center and root cap. We identified 342 protein spots from 550 excised proteins (∼62%) of root apex samples by MALDI‐TOF MS/MS analysis. All these proteins were also present in the differentiated root, but differed in abundance. Functional classification showed that the most numerous protein categories represented in the root were those of stress response, glycolysis, redox homeostasis and protein processing. Using DIGE, we identified 73 differentially accumulated proteins between root apex and differentiated root. Proteins overrepresented in the root apex belonged primarily to the pathways for protein synthesis and processing, cell redox homeostasis and flavonoid biosynthesis. Proteins underrepresented in the root apex were those of glycolysis, tricarboxylic acid metabolism and stress response. Our results highlight the importance of stress and defense response, redox control and flavonoid metabolism in the root apex.
The Arabidopsis thaliana 2‐D gel mitochondrial proteome: Refining the value of reference maps for assessing protein abundance, contaminants and post‐translational modifications
Authors: Taylor Nicolas L. , Heazlewood Joshua L. , Millar A. Harvey
Published: March 2011

Mitochondria undertake the process of oxidative phosphorylation yielding ATP for plant cell maintenance and growth. The principles of isolation and fractionation of plant mitochondrial proteins have been improved over decades, and surveys of the mitochondrial proteome in a number of plants species have been performed. Over time, many quantitative analyses of changes in the plant mitochondrial proteome have been performed by 2‐D gel analyses revealing the induction, degradation and modification of mitochondrial proteins in responses to mutation, stress and development. Here, we present a saturating MS analysis of 2‐D gel separable protein spots from a typical purification of Arabidopsis mitochondria identifying 264 proteins, alongside an LC‐MS/MS survey by non‐gel methods identifying 220 proteins. This allowed us to characterise the major mitochondrial proteins that are not observed on 2‐D gels, the common contaminants and the abundance of the protein machinery of key mitochondrial biochemical pathways, and consider the impact of N‐terminal pre‐sequence cleavage and phosphorylation as explanations of multiple protein spots and the co‐ordinates of proteins on 2‐D gels.
Microarray‐based kinetic colorimetric detection for quantitative multiplex protein phosphorylation analysis
Authors: Holenya Pavlo , Kitanovic Igor , Heigwer Florian , Wölfl Stefan
Published: March 2011

Commonly used colorimetric detection applied to protein microarrays with enzymatic signal amplification leads to non‐linear signal production upon increase in analyte concentration, thereby considerably limiting the range and accuracy of quantitative readout interpretation. To extend the detection range, we developed a kinetic colorimetric detection protocol for the analysis of ELISA microarrays designed to measure multiple phosphorylated proteins using the platforms ArrayTube™ and ArrayStrip™. With our novel quantification approach, microarrays were calibrated over a broad concentration range spanning four orders of magnitude of analyte concentration with picomolar threshold. We used this design for the simultaneous quantitative measurement of 15 phosphorylated proteins on a single chip.
Quantitative proteomic analysis of cold‐responsive proteins in rice
Authors: Neilson Karlie A. , Mariani Michael , Haynes Paul A.
Published: March 2011

Rice is susceptible to cold stress and with a future of climatic instability we will be unable to produce enough rice to satisfy increasing demand. A thorough understanding of the molecular responses to thermal stress is imperative for engineering cultivars, which have greater resistance to low temperature stress. In this study we investigated the proteomic response of rice seedlings to 48, 72 and 96 h of cold stress at 12–14°C. The use of both label‐free and iTRAQ approaches in the analysis of global protein expression enabled us to assess the complementarity of the two techniques for use in plant proteomics. The approaches yielded a similar biological response to cold stress despite a disparity in proteins identified. The label‐free approach identified 236 cold‐responsive proteins compared to 85 in iTRAQ results, with only 24 proteins in common. Functional analysis revealed differential expression of proteins involved in transport, photosynthesis, generation of precursor metabolites and energy; and, more specifically, histones and vitamin B biosynthetic proteins were observed to be affected by cold stress.
MALDI‐imaging mass spectrometry – An emerging technique in plant biology
Authors: Kaspar Stephanie , Peukert Manuela , Svatos Ales , Matros Andrea , Mock Hans‐Peter
Published: March 2011

Recent advances in instrumentation and sample preparation have facilitated the mass spectrometric (MS) imaging of a large variety of biological molecules from small metabolites to large proteins. The technique can be applied at both the tissue and the single‐cell level, and provides information regarding the spatial distribution of specific molecules. Nevertheless, the use of MS imaging in plant science remains far from routine, and there is still a need to adapt protocols to suit specific tissues. We present an overview of MALDI‐imaging MS (MSI) technology and its use for the analysis of plant tissue. Recent methodological developments have been summarized, and the major challenges involved in using MALDI‐MSI, including sample preparation, the analysis of metabolites and peptides, and strategies for data evaluation are all discussed. Some attention is given to the identification of differentially distributed compounds. To date, the use of MALDI‐MSI in plant research has been limited. Examples include leaf surface metabolite maps, the characterization of soluble metabolite translocation in planta, and the profiling of protein/metabolite patterns in cereal grain cross‐sections. Improvements to both sample preparation strategies and analytical platforms (aimed at both spectrum acquisition and post‐acquisition analysis) will enhance the relevance of MALDI‐MSI technology in plant research.
Usefulness of pharmacist‐assisted screening and psychiatric referral program for outpatients with cancer undergoing chemotherapy
Authors: Ito Tatsuhiko , Shimizu Ken , Ichida Yasuhiko , Ishibashi Yuki , Akizuki Nobuya , Ogawa Asao , Fujimori Maiko , Kaneko Naoko , Ueda Ikuyo , Nakayama Kazuhiko , Uchitomi Yosuke
Published: March 2011

Objective: Major depressive disorder (MDD) and adjustment disorder (AD) are common psychiatric disorders in cancer patients but are often overlooked in clinical oncology settings. We introduced a clinical screening program utilizing the Distress and Impact Thermometer (DIT) to identify MDD and AD in cancer outpatients receiving chemotherapy. This study assessed the usefulness of the screening program.

Methods: Pharmacists administered the DIT to consecutive patients undergoing chemotherapy at an outpatient clinic. Psychiatric treatment was recommended to all the patients with positive screening results. The proportion of patients referred to the Psychiatric Service during the program period was then compared with that during a usual care period.

Results: Of the 520 patients who started chemotherapy during the 6‐month program period, 5.0% (26/520) were referred to the Psychiatric Service and 2.7% (15/520) were diagnosed as having MDD or AD. No statistically significant difference in the referral rates was observed between the two periods (2.7 vs 1.0%, p = 0.46). However, the period from the first chemotherapy treatment until the visit to the Psychiatric Service was significantly shorter during the program period than during the period of usual care (12.9±13.2 days vs 55.6±17.6 days, p<0.001).

Conclusions: The proportion of patients referred to the Psychiatric Service for the treatment of MDD or AD during the program period was not different from that during the usual care period. However, the program was useful for introducing psychiatric treatment at an earlier stage. Further modifications to the program to improve the referral rate are necessary. Copyright © 2011 John Wiley & Sons, Ltd.
Composition and biological activity of essential oils from Labiatae against Nezara viridula (Hemiptera: Pentatomidae) soybean pest
Authors: Werdin González Jorge O , Gutiérrez María M , Murray Ana P , Ferrero Adriana A
Published: March 2011

BACKGROUND: Plant essential oils have been recognised as an important natural source of insecticide. This study analysed the chemical constituents and bioactivity of essential oils that were isolated via hydrodistillation from Origanum vulgare L. (oregano) and Thymus vulgaris L. (thyme) against eggs, second instar and adults of Nezara viridula (L.).

RESULTS: The major component of oregano was p‐cymene, and, for thyme, thymol. The ovicidal activity was tested by topical application; the essential oil from thyme was more effective. The fumigant activity was evaluated in an enclosed chamber; the LC50 values for oregano were 26.8 and 285.6 µg mL−1 for nymphs and adults respectively; for thyme they were 8.9 µg mL−1 for nymphs and 219.2 µg mL−1 for adults. To evaluate contact activity, a glass vial bioassay was used; the LC50 values for oregano were 1.7 and 169.2 µg cm−2 for nymphs and adults respectively; for thyme they were 3.5 and 48.8 µg cm−2 respectively. The LT50 analyses for contact and fumigant bioassays indicated that thyme was more toxic for nymphs and adults than oregano. Both oils produced repellency on nymphs and adults.

CONCLUSION: These results showed that the essential oils from O. vulgare and T. vulgaris could be applicable to the management of N. viridula. Copyright © 2011 Society of Chemical Industry
Synthesis of allylic trifluoromethyl ketones and their activity as inhibitors of the sex pheromone of the leopard moth, Zeuzera pyrina L. (Lepidoptera: Cossidae)
Authors: Muñoz Lourdes , Bosch M Pilar , Batllori Lluís , Rosell Glòria , Bosch Dolors , Guerrero Angel , Avilla Jesús
Published: March 2011

BACKGROUND: Trifluoromethyl ketones (TFMKs), structurally related to the pheromones, are good inhibitors of pheromone communication in insects. To determine their activity on Zeuzera pyrina L. (Lepidoptera: Cossidae), a polyphagous pest, the authors have prepared two diunsaturated TFMK analogues of the major (3) and the minor (4) pheromone components, and two monounsaturated ones (5, 6). Their biological activity in electroantennogram (EAG), wind tunnel and field tests is presented.

RESULTS: The synthetic strategy to obtain the allylic TFMKs 3 and 5 is based on the reactions of diene 10 and 1‐octadecene with trifluoroacetaldehyde ethyl hemiacetal, followed by Dess–Martin oxidation of the resulting homoallylic trifluoromethyl alcohols. In EAG, topical application of analogues 3 and 4 on male antennae significantly reduced the pheromone response. In the wind tunnel, compound 4 reduced the number of contacts with the pheromone source. In the field, traps baited with mixtures of pheromone and inhibitors captured significantly fewer males than the pheromone alone.

CONCLUSION: An efficient synthesis of allylic TFMKs is reported, with good overall yield, regiospecificity and diastereoselectivity. These compounds are good inhibitors of the pheromone in electrophysiology, wind tunnel and field tests. The results show the importance of two unsaturations at positions 2 and 13 of the trifluoroacyl group in the structure of the analogues, the latter being critical for inhibitory activity. Copyright © 2011 Society of Chemical Industry
Bombus terrestris as pollinator‐and‐vector to suppress Botrytis cinerea in greenhouse strawberry
Authors: Mommaerts Veerle , Put Kurt , Smagghe Guy
Published: March 2011

BACKGROUND: Bombus terrestris L. bumblebees are widely used as commercial pollinators, but they might also be of help in the battle against economically important crop diseases. This alternative control strategy is referred to as pollinator‐and‐vector technology. The present study was designed to investigate the capacity of B. terrestris to fulfil this role in greenhouse strawberry flowers, which were manually inoculated with a major plant pathogen, the grey mould Botrytis cinerea Pers.: Fr. A model microbiological control agent (MCA) product Prestop‐Mix was loaded in a newly developed two‐way bumblebee dispenser, and, in addition, the use of the diluent Maizena‐Plus (corn starch) was tested.

RESULTS: Importantly, loading of the MCA caused no adverse effects on bumblebee workers, with no loss of survival or impairment of flight activity of the workers during the 4 week flowering period. Secondly, vectoring of Prestop‐Mix by bumblebees resulted in a higher crop production, as 71% of the flowers developed into healthy red strawberries at picking (preharvest yield) as compared with 54% in the controls. In addition, these strawberries were better protected, as 79% of the picked berries remained free of B. cinerea after a 2 day incubation (post‐harvest yield), while this percentage was only 43% in the control. Overall, the total yield (preharvest × post‐harvest) was 2–2.5 times higher than the total yield in the controls (24%) in plants exposed to bumblebees vectoring Prestop‐Mix. Thirdly, the addition of the diluent Maizena‐Plus to Prestop‐Mix at 1:1 (w/w) resulted in a similar yield to that of Prestop‐Mix used alone, and in no negative effects on the bumblebees, flowers and berries.

CONCLUSIONS: This greenhouse study provides strong evidence that B. terrestris bumblebees can vector a MCA to reduce B. cinerea incidence in greenhouse strawberries, resulting in higher yields. Similar yields obtained in the treatments with Prestop‐Mix and Prestop‐Mix + Maizena‐Plus suggest an equally efficient dissemination of the biocontrol agent into the flowers with only half the initial concentration of Prestop‐Mix, which illustrates the importance of the diluent. Copyright © 2011 Society of Chemical Industry
The influence of Al content on impurity states in GaN/AlGaN asymmetrically coupled quantum dots
Authors: Wang T. X. , Li Y. , Liu Y. M.
Published: March 2011

We present a calculation of the donor impurity states in zinc‐blende (ZB) GaN/AlGaN asymmetrically coupled quantum dots (ACQDs). Numerical results show that the donor binding energy is distributed asymmetrically with respect to the center of the ACQDs for any Al composition. It is also found that for an impurity located inside a wide dot, the donor binding energy is insensitive to the middle barrier width (Lmb ≥ 3 nm) in ZB GaN/Al0.15Ga0.85N ACQDs. However, for an impurity located inside a narrow dot, the donor binding energy has a minimum value with increasing Al composition.
Generating function for rotation matrix elements
Authors: Akdemir S. Ö. , Öztekin E.
Published: March 2011

The rotation matrix elements are expressed in terms of the Jacobi, Hypergeometric, and Legendre polynomials in the literature. In this study, the generating function is presented for rotation matrix elements by using properties of Jacobi polynomials. In addition, some special values and Rodrigues' formula of rotation matrix elements are obtained by using the generating function. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2012
Bond dissociation energies for removal of the hydroxyl group in some alcohols from quantum chemical calculations
Authors: Zhao Jun , Zeng Hui , Cheng Xinlu
Published: March 2011

In this theoretical work, 22 alcohols and their geometric structure properties have been investigated employing quantum chemical methods to calculate the COH equilibrium bond distances and bond dissociation energies (BDEs). Since DFT methods have been researched to have low basis sets sensitivity for small and medium molecules in our previous work (Zhao et al., J Mol Struct, 2006, 766, 87), 22 title compounds have been studied by employing the hybrid density functional theory (B3LYP, B3PW91, B3P86, PBE1PBE) in conjunction with the 6‐311G** basis set and the complete basis set (CBS–Q) method. Comparison with the available experimental data shows that CBS–Q and B3P86 methods calculated results agree very well with the experimental values, with the average absolute errors of 1.3 kcal/mol and 3.5 kcal/mol, respectively. So considering the expensive computational time, CBS–Q method can be chosen as a satisfactory method of predicting the accurate BDEs for removal of the OH group in small and medium size alcohols. And B3P86 method may give accurate BDEs for larger alcohols we haven't studied. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2011
Multireference configuration interaction study on spectroscopic parameters and molecular constants of PO and PO+
Authors: Sun Jin‐Feng , Wang Jie‐Min , Shi De‐Heng
Published: March 2011

The highly accurate valence internally contracted multireference configuration interaction (MRCI) approach has been employed to investigate the potential energy curves (PECs) for the X2Π, b4Σ−, C2Σ− states of PO and the X1Σ+ state of PO+. For these electronic states, the spectroscopic parameters of the isotopes (P16O, P18O, P16O+, and P18O+) have been determined and compared with those of the investigations reported in the literature. The comparison shows that excellent agreement exists between the present results and the available experiments. With the PECs determined here, the first 30 vibrational states for P16O(X2Π, b4Σ−), P18O(X2Π, b4Σ−), P16O+(X1Σ+), and P18O+(X1Σ+) are computed when the rotational quantum number J equals zero (J = 0). The vibrational level G(υ), inertial rotation constant Bυ and centrifugal distortion constant Dυ are determined when J = 0. All the results of vibrational states except for P16O (X2Π) are reported for the first time. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2011
Relationship between the molecular structure and the anticancer activity of N‐(2‐chloroethyl)‐N′‐cyclohexyl‐N‐nitrosoureas: A theoretical investigation
Authors: Cao Jun , Zhao Lijiao , Jin Shubin , Zhong Rugang
Published: March 2011

N‐(2‐chloroethyl)‐N′‐cyclohexyl‐N‐nitrosoureas (CCNU) is an important alkylating agent used in the clinical treatment of cancer. The quantitative structure‐activity relationship (QSAR) of CCNU derivatives was investigated using the density functional theory (DFT)‐based descriptors and the n‐octanol/water partition coefficient (milogP). Geometry optimization was performed using the DFT/B3LYP method in conjunction with the 6‐311+G(d,p) basis set. Experimental data of anticancer activity, log(1/C), were used for the QSAR analysis. By stepwise multiple regressions, four optimum descriptors, (milog P)2, E1, EZ/E and BO1Cl8 were found for constructing the QSAR models. Two satisfied models were obtained by multiple linear regressions with the values of R2 higher than 0.9. The (milog P)2 descriptor has the highest correlation to the anticancer activity, indicating that similar improvements to hydrophilicity and lipophilicity are necessary for enhancing anticancer activity. The energy barriers for the decomposition of CCNU derivatives via a retro‐ene reaction (E1) and for the transformation from Z‐tautomers to E‐tautomers (EZ/E) are also considerable descriptors in the QSAR models. The anticancer activity is increased with the decrease of E1 and the increase of EZ/E. The BO1Cl8 descriptor, which requires the inclusion of the other three descriptors in the models, has positive correlation with the anticancer activity of CCNU derivatives. The results indicate that the introduction of the descriptors of activation energies (E1 and EZ/E) is a significant contribution to the methodology of QSAR investigations, because the dynamic descriptors may be more correlated with the biological activity of drugs and toxicants than the static descriptors. Our models shed light on the structure‐activity relationship of CCNU derivatives and may be useful in the development of more effective and less toxic nitrosoureas as anticancer agents. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2011
Determination of pKa for substituted benzoic acids in mixed solvent using density functional theory and QSPR
Authors: Senior Samir A. , Nassar Ahmed M.
Published: March 2011

The pKa of some substituted benzoic acid were calculated using three different methods in 50% ethanol/water at 273.15 K with B3LYP/6‐31G(d,p) level of calculations. The calculated pKas were compared with the experimental values. The quantitative structure property relationship was found to give good results compared with the first principle methods. The solution‐phase quantum chemical descriptors were found to give more accurate pKas than the gas‐phase descriptors. The participation of quantum chemical descriptors as bond lengths and charge density mainly affects the acidity constant of studied compounds as represented by high correlation coefficient factors for the obtained equations. The obtained equations were applied to predict the acidity constant of some related structures to benzoic acid. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2011
Applying sustainable development principles to contaminated land management using the SuRF‐UK framework
Authors: Bardos Paul , Bone Brian , Boyle Richard , Ellis Dave , Evans Frank , Harries Nicola D. , Smith Jonathan W. N.
Published: March 2011

In the past decade, management of historically contaminated land has largely been based on prevention of unacceptable risks to human health and the environment, to ensure a site is “fit for use.” More recently, interest has been shown in including sustainability as a decision‐making criterion. Sustainability concerns include the environmental, social, and economic consequences of risk management activities themselves, and also the opportunities for wider benefit beyond achievement of risk‐reduction goals alone. In the United Kingdom, this interest has led to the formation of a multistakeholder initiative, the UK Sustainable Remediation Forum (SuRF‐UK). This article presents a framework for assessing “sustainable remediation”; describes how it links with the relevant regulatory guidance; reviews the factors considered in sustainability; and looks at the appraisal tools that have been applied to evaluate the wider benefits and impacts of land remediation. The article also describes how the framework relates to recent international developments, including emerging European Union legislation and policy. A large part of this debate has taken place in the “grey” literature, which we review. It is proposed that a practical approach to integrating sustainability within risk‐based contaminated land management offers the possibility of a substantial step forward for the remediation industry, and a new opportunity for international consensus. © 2011 Wiley Periodicals, Inc.
Pitch‐based gender identification with two‐stage classification
Authors: Hu Yakun , Wu Dapeng , Nucci Antonio
Published: March 2011

In this paper, we address the speech‐based gender identification problem. Mel‐Frequency Cepstral Coefficients (MFCC) of voice samples are typically used as the features for gender identification. However, MFCC‐based classification incurs high complexity. This paper proposes a novel pitch‐based gender identification system with a two‐stage classifier to ensure accurate identification and low complexity. The first stage of the classifier identifies and labels all the speakers whose pitch clearly indicates the gender of the speaker; the complexity of this stage is very low since only threshold‐based decision rule on a scalar (i.e., pitch) is used. The ambiguous voice samples from all the other speakers (which cannot be classified with high accuracy by the first stage, and can be regarded as suspicious speakers or difficult cases) are forwarded to the second‐stage for finer examination; the second‐stage of our classifier uses Gaussian Mixture Model to accurately isolate voice samples based on gender. Experiment results show that our system is speech language/content independent, microphone independent, and robust against noisy recording conditions. Our system is extremely accurate with probability of correct classification of 98.65%, and very efficient with about 5 s required for feature extraction and classification. Copyright © 2011 John Wiley & Sons, Ltd.
A Facile Template‐Free Approach for the Large‐Scale Solid‐Phase Synthesis of CdS Nanostructures and Their Excellent Photocatalytic Performance
Authors: Apte Sanjay K. , Garaje Sunil N. , Mane Gurudas P. , Vinu Ajayan , Naik Sonali D. , Amalnerkar Dinesh P. , Kale Bharat B.
Published: March 2011

The simple, template‐free, low‐temperature, large‐scale synthesis of nanostructured CdS with the hexagonal wurtzite phase from bulk cadmium oxide under solid‐phase conditions is demonstrated for the first time. The novel approach involves the homogenization of cadmium oxide (CdO) and thiourea in various stoichiometric ratios at moderate temperature. Among the different molar ratios of CdO and thiourea studied, the CdO/NH2CSNH2 molar ratio of 1:2 is found to be the best to obtain highly pure CdS. The obtained CdS nanostructures exhibit excellent cubic morphology and high specific surface area with a particle size in the range of 5–7 nm. The bandgap of the nanostructured CdS is in the range of 2.42 to 2.46 eV due to its nanocrystalline nature. In photoluminescence studies, emission is observed at 520.34 and 536.42 nm, which is characteristic of the greenish‐yellow region of the visible spectrum. Considering the bandgap of the CdS is within the visible region, the photocatalytic activity for H2 generation and organic dye degradation are performed under visible‐light irradiation. The maximum H2 evolution of 2945 μmol h−1 is obtained using nanostructured CdS prepared in the 1:2 ratio, which is three times higher than that of bulk CdS (1010 μmol h−1). CdS synthesized using the 1:2 molar ratio shows maximum methylene blue degradation (87.5%) over a period of 60 min, which is approximately four times higher than that of bulk CdS (22%). This amazing performance of the material is due to its nanocrystalline nature and the high surface area of the CdS. The proposed simple methodology is believed to be a significant breakthrough in the field of nanotechnology, and the method can be further generalized as a rational preparation scheme for the large‐scale synthesis of various other nanostructured metal sulfides.
Socially Sustainable Work Organizations: Conceptual Contributions and Worldviews
Authors: Kira Mari , van Eijnatten Frans M.
Published: March 2011

This Research Note seeks to add to the body of knowledge concerning social sustainability in work organizations. The Research Note points out how further theoretical work on sustainability in work organizations seems to be needed, and it also emphasizes how promoting sustainability in working life connects to worldviews. Copyright © 2011 John Wiley & Sons, Ltd.
Forest productivity under climate change: a checklist for evaluating model studies
Authors: Medlyn Belinda E. , Duursma Remko A. , Zeppel Melanie J. B.
Published: March 2011

Climate change is highly likely to impact on forest productivity over the next century. The direction and magnitude of change are uncertain because many factors are changing simultaneously, such as atmospheric composition, temperature, rainfall, and land use. Simulation models have been widely used to estimate how these interacting factors might combine to alter forest productivity. Such studies have used many different types of models with different underlying assumptions. To evaluate predictions made by such studies, it is essential to understand the type of model and the assumptions used. In this article, we provide a checklist for use when evaluating modeled estimates of climate change impacts on forest productivity. The checklist highlights the assumptions that we believe are critical in determining model outcomes. Models are classified into different general types, and assumptions relating to effects of atmospheric CO2 concentration, temperature, water availability, nutrient cycling, and disturbance are discussed. Our main aim is to provide a guide to enable correct interpretation of model projections. The article also challenges modelers to improve the quality of information provided about their model assumptions. WIREs Clim Change 2011 2 332–355 DOI: 10.1002/wcc.108

This article is categorized under:

Assessing Impacts of Climate Change > Evaluating Future Impacts of Climate Change
Ciphers
Authors: Stallings William
Published: March 2011

This article surveys three of the most widely used ciphers: the symmetric block cipher, Advanced Encryption Standard (AES), the symmetric stream cipher, RC4, and the asymmetric cipher, RSA. WIREs Comp Stat 2011 3 239–250 DOI: 10.1002/wics.156

This article is categorized under:

Algorithms and Computational Methods > Algorithms

Applications of Computational Statistics > Signal and Image Processing and Coding
Thermally responsive polymer–nanoparticle composites for biomedical applications
Authors: Strong Laura E. , West Jennifer L.
Published: March 2011

Thermally responsive polymer–metal nanoparticle composites couple the ability of certain metal nanoparticles to convert external stimuli to heat with polymers that display sharp property changes in response to temperature changes, allowing for external control over polymer properties. These systems have been investigated for a variety of biomedical applications, including drug delivery, microfluidic valve control, and cancer therapy. This article focuses on three different size scales of this system: bulk systems (>1mm), nano‐ or microscale systems, and individual particle coatings. These composite systems will continue to be widely researched in the future for their vast potential in various biomedical applications. WIREs Nanomed Nanobiotechnol 2011 3 307–317 DOI: 10.1002/wnan.138

This article is categorized under:

Diagnostic Tools > Biosensing

Therapeutic Approaches and Drug Discovery > Emerging Technologies
A Fluorescent Blue Phosphazene Dye: Synthesis, Structure and Optical Properties of 1,6‐Bis(Dimethylamino)‐2,5,7,10‐Tetraazo‐1,6λ5‐Diphosphapyrene
Authors: Lebkücher Anna , Rybina Arina , Herten Dirk‐Peter , Hübner Olaf , Wadepohl Hubert , Kaifer Elisabeth , Himmel Hans‐Jörg
Published: March 2011

Herein we report on the synthesis, structure, and optical properties of the fluorescent blue phosphazene dye 1,6‐bis(dimethylamino)‐2,5,7,10‐tetraazo‐1,6λ5‐diphosphapyrene, which was isolated as the unexpected product of the reaction between 1,4,5,8‐(tetraamino)naphthalene and [P(NMe2)3Br]Br. This dye, which turned out to be soluble in water and a range of organic solvents (including hexane, tetrahydrofuran / petroleum ether, acetonitrile, and ethanol), was structurally characterized by XRD. Its absorption as well as emission spectra and their sensitivity to pH variations were analyzed. The experimental work is complemented by quantum chemical calculations on the possible intermediate on the way to the isolated product and on its pKa value.
False Traumatic Aneurysms and Arteriovenous Fistulas: Retrospective Analysis
Authors: Davidovic Lazar B. , Banzić Igor , Rich Norman , Dragaš Marko , Cvetkovic Slobodan D. , Dimic Andrija
Published: March 2011

Background

The purpose of this study was to analyze the incidence, clinical presentation, diagnosis, and treatment of false traumatic aneurysms and arteriovenous fistulas as well as the outcomes of the patients.

Methods

A retrospective, 16‐year survey has been conducted regarding the cases of patients who underwent surgery for false traumatic aneurysms (FTA) of arteries and traumatic arteriovenous fistulas (TAVF). Patients with iatrogenic AV fistulas and iatrogenic false aneurysms were excluded from the study. There were 36 patients with TAVF and 47 with FTA. In all, 73 (87.95%) were male, and 10 (12.05%) were female, with an average age of 36.93 years (13–82 years).

Results

In 25 (29.76%) cases TAVF and FTA appeared combat‐related, and 59 (70.24%) were in noncombatants. The average of all intervals between the injury and surgery was 919. 8 days (1 day to 41 years) for FTA and 396.6 days (1 day to 9 years) for TAVF. Most of the patients in both groups were surgically treated during the first 30 days after injury. One patient died on the fourth postoperative day. There were two early complications. The early patency rate was 83.34%, and limb salvage was 100%. There were no recurrent AV fistulas that required additional operations.

Conclusions

Because of their history of severe complications, FTA and TAV fistulas require prompt treatment. The treatment is simpler if there is only a short interval between the injury and the operation. Surgical endovascular repair is mostly indicated.
Temporal patterns of growth and nutrient accumulation of plant species in a Mediterranean mountainous grassland
Authors: Mamolos Andreas P. , Vasilikos Charilaos V. , Veresoglou Demetrios S.
Published: March 2011

The temporal patterns of growth and nutrient accumulation into shoots of coexisting species were studied at two neighbouring areas contrasting with respect to long‐term water availability, in an upland herbaceous grassland. Plant growth limiting nutrients were nitrogen (N) in the wet area, and N and phosphorus (P) in the dry area. A series of seven harvests allowed assessment of temporal patterns of peaks for dry matter, N, P and potassium (K) accumulation into shoots and their respective rates of accumulation. Additionally, “pairwise species’ proportion similarities” and “pairwise species’ overlaps” were estimated from shoot biomass data. The peaks of N and P accumulation preceded those of K and dry matter accumulation. Similar trends were evident for the respective rates of accumulation. Compared to the dry area, in the wet area there was a prolonged growing period that increased the inter‐species temporal variability in the rates of nutrient accumulation. Abundance of species was correlated (negatively) to species N and P concentrations only in the dry area. It is argued that the significant negative correlation between abundance and either N or P concentrations in the dry area was indicative of intensified inter‐species competition resulting from declined temporal complementarity.