bluuebunny/crossref_metadata_2025 huggingface dataset:
Multivariate data analysis for finding the relevant fatty acids contributing to the melting fractions of cream
Authors: Buldo Patrizia , Larsen Mette K , Wiking Lars
Published: October 2012

Background

The melting behaviour and fatty acid composition of cream from a total of 33 cows from four farms were analysed. Multivariate data analysis was used to identify the fatty acids that contributed most to the melting points and to differentiate between creams from different practical feeding regimes.

Results

It was demonstrated that the melting point of the medium melting fraction of milk fat was positively correlated with palmitic acid (C16:0), whereas it was negatively correlated with oleic acid (C18:1 cis9), conjugated linoleic acid (CLA cis9 trans11), vaccenic acid (C18:1 trans11), elaic acid (C18:1 trans9) and myristoleic acid (C14:1). The melting points of the high melting fractions could not be related to the fatty acid composition. Addition of palmitic acid‐based fat supplement to the feeding ration in combination with a lower forage intake increased the amount of C16:0 and palmitoleic acid (C16:1) in milk fat, whereas it decreased the amount of stearic acid (C18:0) and C18:1 trans fatty acid. Average data on the melting behaviour of cream separated the farms into two groups where the main differences in feeding were the amounts of maize silage and rapeseed cake used.

Conclusion

Multivariate analysis of data from individual cows identified the most relevant fatty acids contributing to the melting point of the medium melting fraction of cream. The fatty acid composition of milk fat could differentiate cream from different feeding strategies; however, owing to individual cow variation, it was not possible to extract clear correlations between feeding regime and melting behaviour of cream.
Lipase activity, mesocarp oil content, and iodine value in oil palm fruits of Elaeis guineensis, Elaeis oleifera, and the interspecific hybrid O×G (E. oleifera × E. guineensis)
Authors: Cadena Tatiana , Prada Fausto , Perea Aidé , Romero Hernán Mauricio
Published: October 2012

BACKGROUND

One factor affecting crude palm oil quality is the formation of free fatty acids (FFA), often attributed to the hydrolytic action of mesocarp lipase. The aim of this work was to evaluate the enzyme behavior and to look toward new genotypes with low FFA production, high yield, and better oil quality.

RESULTS

Lipase activity was strongly activated at low temperatures (5 °C). At this temperature PLL, SOO, POL, and POO (P, palmitic; L, linoleic; S, stearic; O, oleic) were the most hydrolyzed triacylglycerols in Elaeis guineensis fruits. Ethylene production decreased from 36 nL g−1 h−1 at room temperature to 2 nL g−1 h−1 at 5 °C. Lipase activity of E. guineensis, the E. oleifera × E. guineensis (O×G) hybrid, and E. oleifera were 52.7%, 32.9%, and <0.6% FFA, respectively. The E. guineensis showed oil in the mesocarp of 54.7%, followed by the O×G hybrid (47.0%), and E. oleifera (13.6%), and the iodine values were 52.0, 66.3, and 77.4 g I2 100 g−1, respectively.

CONCLUSIONS

This work allowed the identification of interspecific O×G hybrids as promising crosses with less lipase activity and higher iodine value than E. guineensis. Although O×G crosses produce less oil in the mesocarp than commercial E. guineensis; this feature could be improved by further breeding to introduce new genes from E. oleifera into the hybrids. © 2012 Society of Chemical Industry
A long‐term comparison of the influence of organic and conventional crop management practices on the content of the glycoalkaloid α‐tomatine in tomatoes
Authors: Koh Eunmi , Kaffka Stephen , Mitchell Alyson E
Published: October 2012

Background

α‐Tomatine, synthesized by Lycopersicon and some Solanum species, is a steroidal glycoalkaloid which functions to protect against pathogens and insects. Although glycoalkaloids are generally considered toxic, α‐tomatine appears to be well tolerated in humans. α‐Tomatine has numerous potential health benefits including the ability to inhibit cancer cell growth in in vitro studies. α‐Tomatine is influenced by numerous agronomic factors including fertilization and nitrogen availability. Herein, the levels of α‐tomatine were compared in dried tomato samples (Lycopersicon esculentum L. cv. Halley 3155) produced in organic and conventional cropping systems that had been archived over the period from 1994 to 2004 from the Long Term Research on Agricultural Systems project (LTRAS) at UC Davis.

Results

The α‐tomatine levels of tomatoes in both cropping systems ranged from 4.29 to 111.85 µg g−1 dry weight. Mean levels of α‐tomatine were significantly higher in the organically grown tomatoes than conventional ones (P < 0.001). In the organic management system, α‐tomatine content was also significantly (P < 0.001) different between cropping years, suggesting that other influencing factors such as environmental conditions also affect α‐tomatine content in tomato.

Conclusions

The organically produced tomatoes had higher average α‐tomatine content than their conventional counterpart over the 10‐year study. Significant annual variability in the α‐tomatine content in tomatoes was also observed and suggests that environmental factors, external to nitrogen fertilization, influence α‐tomatine content in tomatoes. © 2012 Society of Chemical Industry
Carotenoid content of wild edible young shoots traditionally consumed in Spain (Asparagus acutifolius L., Humulus lupulus L., Bryonia dioica Jacq. and Tamus communis L.)
Authors: García‐Herrera Patricia , Sánchez‐Mata María Cortes , Cámara Montaña , Tardío Javier , Olmedilla‐Alonso Begoña
Published: October 2012

BACKGROUND

Wild vegetables have traditionally been consumed as part of the Mediterranean diet, being valuable sources of nutrients and bioactive compounds. The objective of this work was to analyse the carotenoid content of the edible young shoots of four species (Asparagus acutifolius L., Humulus lupulus L., Bryonia dioica Jacq. and Tamus communis L.) as part of a wider study on the characterisation of the nutritional composition of wild edible plants commonly consumed in Spain. Samples were gathered from two locations in Central Spain for two consecutive years.

RESULTS

Lutein, β‐carotene, neoxanthin and violaxanthin were quantified by high‐performance liquid chromatography with a photodiode array detector. Median concentration ranges (mg g−1 edible wet weight) were: β‐carotene, 33.9–66.9; lutein, 54.4–191.3; neoxanthin, 51.7–173.7; and violaxanthin, 20.8–89.3. The highest carotenoid content was that of B. dioica (590.1 mg g−1) and the lowest was found in A. acutifolius (175.8 mg g−1).

CONCLUSION

Our results show that these wild young shoots are richer sources of carotenoids than many of the commercially available leafy vegetables. © 2012 Society of Chemical Industry
The effect of antimicrobial photodynamic therapy on human ciliated respiratory mucosa
Authors: Biel Merrill A. , Jones John W. , Pedigo Lisa , Gibbs Aaron , Loebel Nicolas
Published: October 2012

Background:

Chronic recurrent sinusitis (CRS) is one of the most common chronic conditions in the United States. There is a significant subpopulation of CRS patients who remain resistant to cure despite rigorous treatment regimens including surgery, allergy therapy, and prolonged antibiotic therapy. Antimicrobial photodynamic therapy (aPDT) is a noninvasive nonantibiotic broad spectrum antimicrobial treatment. Our previous in vitro studies demonstrated that aPDT reduced CRS polymicrobial biofilm and planktonic bacteria and fungi by > 99.9% after a single treatment. Prior to human treatment however, aPDT treatment must be demonstrated to not result in histologic damage to the sinus ciliated respiratory epithelium. The objective of this study was to demonstrate the safety of aPDT treatment on a living human ciliated respiratory mucosal model (EpiAirway™).

Methods:

A study of aPDT treatment of EpiAirway was performed. Treatment groups included a nontreatment control, laser light alone, photosensitizer alone, and therapeutic photosensitizer and light combination (aPDT). At completion of treatment, the EpiAirway tissue was fixed in 10% formalin, paraffin‐embedded, sectioned, H&E stained and mounted. All samples were blinded and microscopically examined by a human pathologist to assess any effect of aPDT on the tissue, cilia, or mucosal glands. The results were correlated with the treatment parameters.

Results:

The EpiAirway histologic study demonstrated no histologic alteration of the respiratory cilia or mucosal epithelium in any of the treatment groups.

Conclusions:

aPDT is a safe treatment for CRS resulting in no histologic alteration of human ciliated respiratory mucosa as is found in the human sinuses. Laryngoscope, 2012
Bile acids in laryngopharyngeal refluxate: Will they enhance or attenuate the action of pepsin?
Authors: Ali Mahmoud S. , Parikh Shruti , Chater Peter , Pearson Jeffrey P.
Published: October 2012

Objectives/Hypothesis:

To assess if, as previously reported in the literature, bile acids inhibit pepsin activity, resulting in pepsin having a less important role in laryngopharyngeal damage in reflux disease.

Study Design:

Prospective translational research study.

Methods:

A total of 78 patient's fasting gastric juice samples were obtained from routine endoscopy. The total bile acid (TBA) content and pepsin activity were measured using a 3α‐hydroxysteroid dehydrogenase–based kit for bile acids; and pepsin activity was measured using succinyl albumin/dimethylhaemoglobin as a substrate and the development of new N‐terminals. The ability of bile acids to effect pepsin activity was assessed with three primary bile acids, two unconjugated and one taurine conjugated, using the above N‐terminal assay.

Results:

Gastric juice contained median TBA of 40 (range 10–10010) μM and pepsin activity of 408 (range 27–3892)ug/ml. We used this data to inform the relative levels of pepsin and bile acids that might occur in a reflux event, and we used concentrations of bile acids between 10–100μM.

Pepsin activity was pH dependent, but 28% of the activity was retained at pH 5.5. None of the bile acids showed any significant effect on pepsin activity across the pH range 2.0–6.0.

Conclusions:

At the levels and pH that pepsin and bile acids might occur in an LPR event, bile acids do not attenuate pepsin activity. Pepsin could be considered a damaging factor even at high pH, and it will aggravate further any damaging effects of bile acids in the refluxate. Laryngoscope, 2012
On the degree of compositum of two number fields
Authors: Drungilas Paulius , Dubickas Artūras , Luca Florian
Published: October 2012

We prove that the sum of two algebraic numbers both of degree 6 cannot be of degree 8. The triplet (6, 6, 8) was the only undecided case in the previous characterization of all positive integer triplets (a, b, c), with a ≤ b ≤ c and b ≤ 6, for which there exist algebraic numbers α, β and γ of degrees a, b and c, respectively, such that α + β + γ = 0. Now, this characterization is extended up to b ≤ 7. We also solve a similar problem for \documentclass{article}\usepackage{amssymb}\begin{document}\pagestyle{empty}$(a,b,c) \in \mathbb N^3$\end{document} with a ≤ b ≤ 7 by finding for which positive integers a, b, c there exist number fields of degrees a and b such that their compositum has degree c. We show that the problem of describing all compositum‐feasible triplets can be reduced to some finite computation in transitive permutation groups of degree c which occur as Galois groups of irreducible polynomials of degree c. In particular, by exploiting the properties of the projective special linear group PSL(2, 7) of order 168, we prove that the triplet (7, 7, 28) is compositum‐feasible. In the opposite direction, the triplet (p, p, p(p − ℓ)), where ℓ ≥ 2 is an integer and p > ℓ2 − ℓ + 1 is a prime number, is shown to be not compositum‐feasible, not sum‐feasible and not product‐feasible.
Increase of the computational accuracy of hot bulk forming process simulations with improved friction modeling
Authors: Bouguecha A. , Hadifi T. , Mielke J. , Behrens B.‐A.
Published: October 2012

Die Ressourceneffizienz von Fertigungsverfahren setzt den genauen Einsatz von Energie und vom Rohteilmaterial voraus. Hierbei spielt insbesondere in der Umformtechnik die gezielte simulationsgestützte Auslegung des Prozesses eine bedeutende Rolle. Ein etabliertes Berechnungsverfahren stellt die Finite‐Element‐Methode (FEM) dar. Mit ihrem Einsatz werden kosten‐ und zeitintensive Trial‐and‐Error‐Versuche reduziert und im besten Fall sogar zuverlässig vermieden. Dabei ist eine realitätsnahe Beschreibung der komplexen Wirkmechanismen in der Interaktion zwischen Werkzeug und Werkstück über eine geeignete Reibmodellierung entscheidend. In diesem Beitrag wird das neu entwickelte IFUM‐Reibmodell und dessen Einsatz bei der FE‐Berechnung komplexer Schmiedeprozesse vorgestellt.
EBSD – orientation analysis of monocrystalline diamonds used for diamond metal composites – Influence of sample preparation
Authors: Tillmann W. , Biermann D. , Weihs C. , Ferreira M. , Rautert C. , Raabe N.
Published: October 2012

This paper focuses on a new field of application for the EBSD‐technique. Generally, EBSD‐mappings are performed on different metal alloys used for quality assurance and to get information about the microstructure regarding grain orientation, grain size and distribution. In contrast, the orientation determination of monocrystalline diamond grains with an EBSD system is not a conventional method. Thus, this work describes the EBSD testing sequence in detail and illustrates the preparation of orientation data for a statistical design. Furthermore, dependencies of the sample preparation, alignment to the detector, and the analyzed position on the diamond on the quality of the Kikuchi‐patterns, respectively on the indexing rates, have been scrutinized. Finally, the orientation obtained of each tested diamond sample has been utilized in a statistical design to show a direct influence of the crystal orientation on the wear behavior of the diamond grains.
Generalized eigenvalue decomposition of the field autocorrelation in correlation diffusion of photons in turbid media
Authors: Hyvönen N. , Nandakumaran A. K. , Varma H. M. , Vasu R. M.
Published: October 2012

We propose a novel numerical method based on a generalized eigenvalue decomposition for solving the diffusion equation governing the correlation diffusion of photons in turbid media. Medical imaging modalities such as diffuse correlation tomography and ultrasound‐modulated optical tomography have the (elliptic) diffusion equation parameterized by a time variable as the forward model. Hitherto, for the computation of the correlation function, the diffusion equation is solved repeatedly over the time parameter. We show that the use of a certain time‐independent generalized eigenfunction basis results in the decoupling of the spatial and time dependence of the correlation function, thus allowing greater computational efficiency in arriving at the forward solution. Besides presenting the mathematical analysis of the generalized eigenvalue problem on the basis of spectral theory, we put forth the numerical results that compare the proposed numerical method with the standard technique for solving the diffusion equation. Copyright © 2012 John Wiley & Sons, Ltd.
The existence of periodic solutions of higher order nonlinear periodic difference equations
Authors: Liu Yuji , Liu Xingyuan
Published: October 2012

Sufficient conditions for the existence of at least one periodic solution of two classes of nonlinear higher order periodic difference equations are established, respectively. The results show us that sufficient conditions for the existence of T − periodic solutions of difference equation are different from those ones for the existence of T − periodic solutions of differential equation. Copyright © 2012 John Wiley & Sons, Ltd.
Global classical solutions to partially dissipative quasilinear hyperbolic systems with weaker restrictions on wave interactions
Authors: Qu Peng
Published: October 2012

A kind of partially dissipative quasilinear hyperbolic systems in which a part of equations possesses the strict dissipation and the others are weakly linearly degenerate are discussed. Under some weaker hypotheses on the interactions between two parts of equations, it is proved that for any given initial data with small W1,1 and C1 norms, the corresponding Cauchy problem admits a unique C1 global classical solution. Copyright © 2012 John Wiley & Sons, Ltd.
Multiplicity result for asymptotically linear noncooperative elliptic systems
Authors: Liu Guanggang , Shi Shaoyun , Wei Yucheng
Published: October 2012

In this paper, we obtain a multiplicity result for a class of asymptotically linear noncooperative elliptic systems by using saddle point reduction technique and two abstract critical point theorems. Copyright © 2012 John Wiley & Sons, Ltd.
Use of folic acid supplements in early pregnancy in relation to maternal plasma levels in week 18 of pregnancy
Authors: Roth Christine , Bjørke‐Monsen Anne L. , Reichborn‐Kjennerud Ted , Nilsen Roy M. , Smith George D. , Stoltenberg Camilla , Surén Pål , Susser Ezra , Ueland Per M. , Vollset Stein E. , Magnus Per
Published: October 2012

Scope

Birth cohorts typically measure plasma folate in midgestation, but effects of folic acid supplementation are sometimes specific to the periconceptional period. The relationship between midgestation plasma folate and periconceptional supplementation is not known. We compared plasma folate at week 18 of gestation with self‐report use of supplements comtaining folic acid from before pregnancy to week 17 of gestation.

Methods and Results

The sample comprised 2911 women from The Norwegian Mother and Child Cohort Study. For women reporting continuous supplementation from gestational week −4 to 17 (N = 238), median plasma folate was 15.72 at week 18 (in nmol/L). This was about threefold higher than the median plasma folate of 5.67 for women reporting no supplementation from week −4 to 17 (N = 844), but only slightly higher than the median plasma folate of 13.34 for all women reporting supplementation in weeks 13–17 (N = 1158). Reported supplementation before week 8 was not associated with plasma folate at week 18, in an analysis that adjusted for continued supplementation after week 8.

Conclusion

Overall we found a strong and coherent relationship between self‐reported folic acid use and plasma folate at week 18. We also found that plasma folate at week 18 did not reflect self‐reported supplementation before week 8. For periconceptional supplementation per se, self‐report data may offer a better measure.
Involvement of de novo ceramide synthesis in gamma‐tocopherol and gamma‐tocotrienol‐induced apoptosis in human breast cancer cells
Authors: Gopalan Archana , Yu Weiping , Jiang Qing , Jang Yumi , Sanders Bob G. , Kline Kimberly
Published: October 2012

Scope

This study further examines mechanisms involved in the pro‐apoptotic action of gamma‐tocopherol (γT) and gamma‐tocotrienol (γT3) in human breast cancer cell lines.

Methods and results

γT upregulates phospho‐JNK (pJNK), CCAAT/enhancer‐binding protein homologous protein (CHOP), and death receptor‐5 (DR5) protein expression as detected by Western blot assays. siRNA knockdown of JNK, CHOP, or DR5 shows that γT‐induced apoptosis is JNK/CHOP/DR5 signaling dependent, which is similar to γT3‐mediated apoptotic signaling. Furthermore, both γT and γT3 induce increased levels of cellular ceramides and dihydroceramides as determined by LC‐MS/MS analyses. Inhibition of de novo ceramide synthesis using chemical inhibitors blocked the ability of γT and γT3 to induce apoptosis as detected by Annexin V‐FITC/PI assay and to activate JNK/CHOP/DR5 pro‐apoptotic signaling thereby demonstrating the involvement of de novo ceramide synthesis in γT‐ and γT3‐induced apoptosis.

Conclusion

Taken together, data show that both γT and γT3 induce apoptosis via de novo ceramide synthesis dependent activation of JNK/CHOP/DR5 pro‐apoptotic signaling.
Molecular cloning and localization of a CEACAM2 isoform, CEACAM2‐L, expressed in spermatids in mouse testis
Authors: Salaheldeen Elsaid , Kurio Hitoshi , Howida Ali , Iida Hiroshi
Published: October 2012

Carcinoembryonic antigen (CEA) family, a subgroup of the immunoglobulin (Ig) superfamily, is divided into two sub‐families: the CEA‐related cell adhesion molecules (CEACAM) and the pregnancy‐specific glycoproteins. The isoform CEACAM2 is expressed in mouse testis; in this study, we identified a novel isoform of Ceacam2, Ceacam2‐Long (Ceacam2‐L). CEACAM2‐L is different from CEACAM2 in that it has much longer cytoplasmic tail region. Ceacam2‐L starts to appear faintly in mouse testis after 3 weeks of postnatal development, and its expression level increased after 5 weeks. Immunoblot analysis confirmed the expression of CEACAM2‐L in the seminiferous epithelium of mouse testis. Immunohistochemical data showed that CEACAM2‐L was not observed on spermatogonia, spermatocytes, round spermatids, or Sertoli cells, but was seen at the plasma membrane of elongating spermatids in contact with extended cytoplasmic processes of Sertoli cells. CEACAM2‐L was not detected at the head region of elongating spermatids, where the apical ectoplasmic specialization is constructed. These data suggest that CEACAM2‐L might be a novel adhesion molecule contributing to cell‐to‐cell adhesion between elongating spermatids and Sertoli cells within the seminiferous epithelium. Mol. Reprod. Dev. 79: 843–852, 2012. © 2012 Wiley Periodicals, Inc.
Synthesis of Stereoblock Elastomeric Poly(propylene)s Using a (2‐PhInd)2ZrCl2 Metallocene Catalyst in the Presence of Co‐Catalyst Mixtures: Study of Activity and Molecular Weight
Authors: Nejabat Gholam‐Reza , Nekoomanesh Mehdi , Arabi Hassan , Salehi‐Mobarakeh Hamid , Zohuri Gholam‐Hossein , Omidvar Mojtaba , Miller Stephen A.
Published: October 2012

The effect of adding various aluminum alkyls (R = Et, i‐Bu) on the polymerization of propylene is studied using a (2‐PhInd)2ZrCl2 pre‐catalyst. A mild deactivating effect is found upon addition of TIBA, whereas TEA shows a sharp deactivating effect. Increasing amounts of AlR3 results in a significant activity increase for TIBA, but an activity plateau for TEA. AlR3 imposes remarkably different effects on the molecular weight and stereochemical microstructure of polymers. As the TIBA concentration increases, $\overline {M} _{{\rm v}} $ increases at first, growing from 49 000 to 72 000, but subsequently drops to 40 000. For TEA, $\overline {M} _{{\rm v}} $ decreases sharply, plummeting from 49 000 to 17 000. Both TIBA and TEA increase the mmmm pentad content from 7.9 to 23.5% and 17.6%, respectively.

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Novel basis functions for the partition of unity boundary element method for Helmholtz problems
Authors: Peake M.J. , Trevelyan J. , Coates G.
Published: October 2012

The BEM is a popular technique for wave scattering problems given its inherent ability to deal with infinite domains. In the last decade, the partition of unity BEM, in which the approximation space is enriched with a linear combination of plane waves, has been developed; this significantly reduces the number of DOFs required per wavelength. It has been shown that the element ends are more susceptible to errors in the approximation than the mid‐element regions. In this paper, the authors propose that this is due to the use of a collocation approach in combination with a reduced order of continuity in the Lagrangian shape function component of the basis functions. It is demonstrated, using numerical examples, that choosing trigonometric shape functions, rather than classical polynomial shape functions (quadratic in this case), provides accuracy benefits. Collocation schemes are investigated; it is found that the somewhat arbitrary choice of collocating at equally spaced points about the surface of a scatterer is better than schemes based on the roots of polynomials or consideration of the Fock domain. Copyright © 2012 John Wiley & Sons, Ltd.
Interruptions during nurses' work: A state‐of‐the‐science review
Authors: Hopkinson Susan G. , Jennings Bonnie Mowinski
Published: October 2012

The purpose of this state‐of‐the‐science review was to examine empirical evidence from studies of interruptions conducted in acute care nurses' work environments. A total of 791 articles published from 2001 through 2011 were reviewed; 31 met the criteria to be included in the sample. Despite sustained multinational and multidisciplinary attention to interruptions during nurses' work, the current findings suggest that beliefs about the ill effects of interruptions remain more conjecture than evidence‐based. Pre‐existing beliefs and biases may interfere with deriving a more accurate grasp of interruptions and their effects. Future research would benefit from examinations of interruptions that better capture their complexity, to include their relationships to both positive and negative outcomes for both patients and health care workers. © 2012 Wiley Periodicals, Inc. Res Nurs Health 36:38–53, 2013
Nanoclay‐reinforced poly(butylene adipate‐co‐terephthalate) biocomposites for packaging applications
Authors: Bittmann Birgit , Bouza Rebeca , Barral Luis , González‐Rodríguez M. Victoria , Abad María‐José
Published: October 2012

Increasing generation and inadequate disposal of waste progressively compromise our environment. Solutions are proposed by the development of biodegradable polymers, that is, for short‐term applications like packaging. The present study focuses on the design and characterization of biodegradable poly(butylene adipate‐co‐terephthalate) (PBAT) nanocomposites reinforced by different types of nanoclays. The addition of natural and modified montmorillonite and bentonite to PBAT by melt mixing enhances slightly the thermal stability and increases the crystallization temperature, independently of the fillers' dispersion state. By contrast, storage modulus in dynamic mechanical analysis is increased when adding nanoclay, and improvement is higher for well‐dispersed organomodified fillers. Dispersion states and morphology of the nanocomposites are studied by X‐ray diffraction as well as scanning and transmission electron microscopy. PBAT‐based composites with modified bentonite reveal to show the best performance at room temperature (which is the temperature of interest for potential packaging applications) in comparison with the other investigated nanocomposites.POLYM. COMPOS., 33:2022–2028, 2012. © 2012 Society of Plastics Engineers
Rheological properties and microstructures of cellulose acetate phthalate/hydroxypropyl cellulose blends
Authors: Dobos Adina Maria , Onofrei Mihaela‐Dorina , Stoica Iuliana , Olaru Niculae , Olaru Liliana , Ioan Silvia
Published: October 2012

Cellulose acetate phthalate (CAP)/hydroxypropyl cellulose (HPC) blends were investigated by means of attenuated total reflection‐Fourier transform infrared spectroscopy, thermogravimetry/differential thermal analysis, shear viscosity, oscillatory shear tests, and atomic force microscopy (AFM). Effect of solution concentrations in 2‐methoxyethanol, blend compositions, and shear rate on the rheological functions reflects the mobility of the chain segments or their orientation—with thinning behavior in the shear field. Specific interactions, such as the hydrogen bonds between polymer components and 2‐methoxyethanol used in casting solutions of films, influence the resulting morphology. Supernodular aggregates with different intensities and dimensions, which involve the coexistence of an isotropic and an anisotropic phase, typical for lyotropic cellulosic derivative liquid crystals at low concentrations, are evidenced by AFM images. This study is useful for applications of CAP/HPC blends in pharmaceutical domains.POLYM. COMPOS., 33:2072–2083, 2012. © 2012 Society of Plastics Engineers
Type 1 diabetes: not lost but possibly misplaced
Authors: Sharp Patrick , Walton Chris
Published: October 2012

‘You have type 1 diabetes, but you don't need to see a specialist for treatment of your diabetes. It can all be done in the practice.’
Micromechanical models for carbon nanotube and cellulose nanowhisker reinforced composites
Authors: Loos M.R. , Manas‐Zloczower I.
Published: October 2012

Different micromechanical models which account for the presence of dispersed and agglomerated nanofillers, specifically carbon nanotubes (CNTs) and cellulose nanowhiskers (CWs), in a polymeric matrix and consider the effect of a percolation threshold on the elastic modulus of the composite are derived and compared. We demonstrate that the critical filler volume fraction where a percolating network is forming marks a “turning point” in the reinforcement efficiency. The suitability of these models is verified by comparing simulated values with experimental data from literature. The results show that the models are able to predict mechanical properties over a wide range of testing conditions. POLYM. ENG. SCI., 2013. © Society of Plastics Engineers
Covalent functionalization of carbon nanotubes with polyhedral oligomeric silsequioxane for superhydrophobicity and flame retardancy
Authors: Tang Yong , Gou Jihua , Hu Yuan
Published: October 2012

Multiwalled carbon nanotubes (MWCNTs) were covalently functionalized with polyhedral oligomeric silsequioxane (POSS). The results of Fourier Transform Infrared Spectroscopy, Raman spectroscopy and Transmission Electron Microscopy indicated that POSS particles were grafted onto MWCNTs. The POSS content determined by thermo‐gravimetric analysis (TGA) was estimated to be ∼25 wt%. A stable and superhydrophobic surface characteristic was observed for the film made of MWCNTs grafted with POSS (MWCNT‐g‐POSS) even after an exposure to a high‐humidity environment for three weeks. The water contact angle of the sample was measured to be 160.5 ± 1.1°. Buckypapers were made from both pristine MWCNTs and chemically converted to MWCNT‐g‐POSS. The pore structures of the buckypapers were characterized by mercury intrusion porosimetry and scanning electron microscopy. The flame‐retardant performance of the buckypaper‐based composites was evaluated by TGA and microscale combustion calorimetry (MCC) test. The TGA test results indicated that the MWCNT‐g‐POSS dramatically increased the char residues of the composite. Approximately 72% reduction in peak heat release rate was achieved for the MWCNT‐g‐POSS /resin composite from the MCC testing. The fire‐retardant mechanism was discussed. POLYM. ENG. SCI., 2013. © Society of Plastics Engineers
Synthesis of polylactide/poly(ethylene glycol) diblock copolymers with functional endgroups
Authors: Wu Xiaohan , Li Suming
Published: October 2012

Amphiphilic polylactide/poly(ethylene glycol) (PLA–PEG) diblock copolymers with functional groups at the PEG chain ends were synthesized by coupling PLA and PEG homopolymers using different coupling agents. PLA precursors with different endgroups were synthesized by ring‐opening polymerization of l‐lactide in the presence of different initiators such as octanol, acetic acid or benzoic acid, or water, using non‐toxic zinc lactate as catalyst. The mechanism of the ring‐opening polymerization of lactide initiated by carboxyl groups was investigated and discussed in comparison with the literature. N,N'‐carbonyldiimidazole was used to couple the two hydroxyl groups of PLA and PEG, using 4‐dimethylaminopyridine (DMAP) as catalyst. Dicyclohexylcarbodiimide (DCC) and DMAP were adopted to couple the carboxyl group and the hydroxyl group of PLA and PEG, respectively, while DCC and N‐hydroxysuccinimide were used to connect PLA and PEG by coupling their carboxyl and amine groups. Comparison of different coupling routes shows that the DCC/DMAP one exhibits the highest efficiency. A common tumor targeting ligand, folic acid, was attached to PLA–PEG with hydroxyl endgroups using the DCC/DMAP route. The resulting PLA–PEG copolymers bearing folic acid present great interest for targeted delivery of anti‐cancer drugs. © 2012 Society of Chemical Industry
Fracture toughness of poly(lactic acid)/ ethylene acrylate copolymer/wood‐flour composite ternary blends
Authors: Afrifah Kojo A , Matuana Laurent M
Published: October 2012

A fracture mechanics analysis based on the J‐integral method was adopted to determine the resistance of composites with various concentrations of wood‐flour and ethylene acrylate copolymer (EAC) to crack initiation (Jin) and complete fracture (Jf). The Jin and Jf energies of unmodified poly(lactic acid) (PLA)/wood‐flour composites showed the deleterious effect of incorporating wood fibers into the plastic matrix by significantly decreasing the fracture toughness of PLA as the wood‐flour content increased. The reduced fracture toughness of the matrix induced by adding brittle wood‐flour into PLA was well recovered by impact modification of the composites with EAC. Microscopic morphological studies revealed that the major mechanisms of toughening were through the EAC existing as separate domains in the bulk matrix of the composites which tended to act as stress concentrators that initiated local yielding of the matrix around crack tips and enhanced the toughness of the composites. © 2012 Society of Chemical Industry
A National Study of Autistic Symptoms in the General Population of School‐Age Children and Those Diagnosed with Autism Spectrum Disorders
Authors: Goldstein Sam , Naglieri Jack A. , Rzepa Sara , Williams Kevin M.
Published: October 2012

We examined the interrelationships among symptoms related to autism spectrum disorders (ASD) using a large representative sample and clinical groups of children aged 6 to 11 and youth aged 12 to 18 years rated by parents (N = 1,881) or teachers (N = 2,171). The samples included individuals from the United States and Canada from the standardization and validity studies for the Autism Spectrum Rating Scales. A three‐factor solution comprising Social/Communication, Unusual Behaviors, and Self‐Regulation provided the best fit to the data and was replicated across parent and teacher ratings. High coefficients of congruence across sexes, raters, ethnic groups, and age groups and for clinical groups were obtained. Implications for understanding the symptoms related to ASD and their use in practice are provided.
A process to provide harmonised criteria for the selection of indicators for pesticide risk reduction within the framework of the sustainable use directive
Authors: Calliera Maura , Marchis Alex , Bollmohr Silke , Sacchettini Gabriele , Lamastra Lucrezia , Capri Ettore
Published: October 2012

In October 2009, the Council of the European Union adopted the Directive on Sustainable Use of Pesticides (EU 128/2009/EC). This directive establishes a framework to achieve the sustainable use of pesticides by reducing the risk and impacts of pesticide use on both human health and the environment, and promoting the use of integrated pest management and of alternative approaches or techniques. These risks thus need to be assessed using appropriate risk indicators. The OPERA Research Centre organised an expert working group and has had several consultations with stakeholders in order to identify a common way of thinking in evaluating and identifying the factors that should be considered in selecting each indicator. Harmonised criteria have been suggested to allow the selection of the most appropriate indicators, focusing on the use phase of pesticide, as requested by the sustainable use directive. The proposed methodology has led to a sharing of perspectives and knowledge between the experts involved, and some principles have been identified to help national regulatory institutions to estimate general trends in pesticide risk reduction.
Synthesis of graphene by surface wave plasma chemical vapor deposition from camphor
Authors: Kalita Golap , Sharma Subash , Wakita Koichi , Umeno Masayoshi , Hayashi Yasuhiko , Tanemura Masaki
Published: October 2012

We demonstrate synthesis of graphene using the solid precursor camphor in a microwave excited surface wave plasma chemical vapor deposition technique. Highly sublimely camphor was introduced into the plasma chamber in the vapor phase along with Ar and uniform plasma formation was obtained. Rapid deposition of a graphene film on Cu foil was achieved at a relatively low temperature (<600 °C). Raman spectroscopy and transmission electron microscopy clearly showed that the deposited film on Cu foil consist of few‐layer graphene. Fully flexible transparent electrode was fabricated by transferring the graphene film with excellent properties for device application.

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Synthesis of large‐area graphene film from solid botanical derivative camphor (C10H16O) in a surface wave microwave plasma CVD technique.
The Estrogenic Activity of Isoflavones Extracted from Chickpea Cicer arietinum L Sprouts in Vitro
Authors: HaiRong Ma , HuaBo Wei , Zhen Chen , Yi Yang , ZhengHua Wang , Madina Habasi , Xu Cao , Haji Akber Aisa
Published: October 2012

Isoflavones have drawn attention due to their potential therapeutic use. Isoflavones are the important chemical components of the seeds and sprouts of chickpea and higher isoflavones in sprouts than in seeds. However, there have been no previous reports of the estrogenic activity of isoflavones extracted from chickpea Cicer arietinum L sprouts (ICS) in vitro. In this study, which incorporated several in vitro bioassays methods, we systematically evaluated the estrogenic properties of ICS. MTT assay showed that ICS at the low concentration ranges (10−3–1 mg/L) promoted MCF‐7 cell growth, while at high concentrations, (>1 mg/L) inhibited cell proliferation, indicating ICS worked at a diphasic mechanism. Flow cytometric analysis further calculated the proliferation rate of ICS at low concentration (1 mg/L). ERα/Luc trans‐activation assay and then semi‐quantitative RT‐PCR analysis indicated that ICS at low concentrations induced ERα‐mediated luciferase activity in MCF‐7 cells and promoted the ER downstream target gene pS2 and PR trans‐activation. These effects were inhibited by ICI 182,780, a special antagonist of ER, indicating that an ER‐mediating pathway was involved. Alkaline phosphatase (AP) expression in Ishikawa cells showed that ICS at low concentrations stimulated AP expression. Our current study is the first to demonstrate that ICS has significant estrogenic activity in vitro. ICS may be useful as a supplement to hormone replacement therapy and in dietary supplements. Copyright © 2012 John Wiley & Sons, Ltd.
Exact axisymmetric solutions of the deep‐ and shallow‐atmosphere Euler equations in curvilinear and plane geometries
Authors: Staniforth Andrew , Wood Nigel
Published: October 2012

A wide family of exact closed‐form axisymmetric solutions to the deep‐ and shallow‐atmosphere Euler equations is derived. These solutions are not only valid in general curvilinear geometry, but also in beta‐plane and beta–gamma‐plane geometries. A further generalisation of the generalised thermal wind equation is also derived. The enhanced generality of the exact solutions developed herein provides more flexibility in the specification of initial conditions for numerical model validation. This permits the construction not only of more challenging, balanced, shallow‐ and deep‐atmosphere solutions than has hitherto been possible, but also of more elaborate tests of the baroclinic wave type. Copyright © 2012 British Crown copyright, the Met Office. Published by John Wiley & Sons Ltd.
A rainfall calibration methodology for impacts modelling based on spatial mapping
Authors: Di Giuseppe Francesca , Molteni Franco , Tompkins Adrian M.
Published: October 2012

A spatially based precipitation bias correction is introduced that generalizes existing approaches. The method consists of projecting observed precipitation anomalies on to the model's modes of variability for a large set of model hindcasts to produce artificial mapped empirical orthogonal functions, which are used to bias correct forecasts. Similar to previous spatially based methods, the scheme can shift displaced anomalies, associated with the West African monsoon progression for example, to their correct location, and by construction produces a corrected field with a zero‐mean bias with respect to the observations. The new method has the advantage that it only applies corrections to modes of variability for which the model has proven skill, and does not rely on a one‐to‐one direct correspondence between the observational and model modes, a restriction of previous methods. By processing the precipitation fields in sequences of seven pentad averages, it is also possible to including variability on shorter than monthly time‐scales, important if the end product is to be used for end‐user impact‐focused research. The method is tested for various empirical orthogonal function‐defined climate macro regions within Africa and is shown to reduce biases while also improving threat skill scores over a range of thresholds and forecast lead times.
Development and validation of observing‐system simulation experiments at NASA's Global Modeling and Assimilation Office
Authors: Errico Ronald M. , Yang Runhua , Privé Nikki C. , Tai King‐Sheng , Todling Ricardo , Sienkiewicz Meta E. , Guo Jing
Published: October 2012

Initial design and validation of baseline Observing System Simulation Experiments (OSSEs) at NASA's Global Modeling and Assimilation Office (GMAO) are described. The OSSEs mimic the procedures used to analyze global observations for specifying states of the atmosphere. As simulations, however, OSSEs are not only confined to already existing observations and they provide a perfect description of the true state being analyzed. These two properties of the simulations can be exploited to improve both existing and envisioned observing systems and the algorithms to analyze them. Preliminary to any applications, however, the OSSE framework must be adequately validated.

This first version of the simulated observations is drawn from a 13 month simulation of nature produced by the European Center for Medium‐Range Weather Forecasts. These observations include simulated errors of both instruments and representativeness. Since the statistics of analysis and forecast errors are partially determined by these observational errors, their appropriate modelling can be crucial for validating the realism of the OSSE. That validation is performed by comparing the statistics of the results of assimilating these simulated observations for one summer month compared with the corresponding statistics obtained from assimilating real observations during the same time of year. The assimilation system is the three‐dimensional variational analysis (GSI) scheme used at both the National Centers for Environmental Prediction and GMAO. Here, only statistics concerning observation innovations or analysis increments within the troposphere are considered for the validation.

In terms of the examined statistics, the OSSE is validated remarkably well, even with some simplifications currently employed. In order to obtain this degree of success, it was necessary to employ horizontally correlated observation errors for both atmospheric motion vectors and some satellite observed radiances. The simulated observations with added observation errors appear suitable for some initial OSSE applications.
In Situ Control of Cell Substrate Microtopographies Using Photolabile Hydrogels
Authors: Magin Chelsea M. , Anseth Kristi S.
Published: October 2012

Substratum topography can play a significant role in regulating cellular function and fate. To study cellular responses to biophysical cues, researchers have developed dynamic methods for controlling cell morphology; however, many of these platforms are limited to one transition between two predefined substratum topographies. To afford the user additional control over the presentation of microtopographic cues to cell populations, a photolabile, PEG‐based hydrogel system is presented in which precisely engineered topographic cues can be formed in situ by controlled erosion. Here, the ability to produce precisely engineered static microtopographies in the hydrogel surface is first established. Human mesenchymal stem cell (hMSC) response to topographies with features of subcellular dimensions (∼5 to 40 μm) and with various aspect ratios increasing from 1:1 to infinity (e.g., channels) are quantified, and the dynamic nature of the culture system is demonstrated by sequentially presenting a series of topographies through in situ modifications and quantifying reversible changes in cell morphology in response to substratum topographies altered in real time.
Wind characteristics in the North and Baltic Seas from the QuikSCAT satellite
Authors: Karagali Ioanna , Peña Alfredo , Badger Merete , Hasager Charlotte Bay
Published: October 2012

The QuikSCAT mission provided valuable daily information on global ocean wind speed and direction from July 1999 until November 2009 for various applications including numerical weather prediction, ocean and atmospheric modelling. One new and important application for wind vector satellite data is offshore wind energy, where accurate and frequent measurements are required for siting and operating modern wind farms. The greatest advantage of satellite observations rests in their extended spatial coverage. This paper presents analyses of the 10 year data set from QuikSCAT, for the overview of the wind characteristics observed in the North and Baltic Seas, where most of Europe's offshore wind farms operate and more will be constructed. Significant issues in data availability are identified, directly related to the flagging schemes. In situ observations from three locations in the North Sea are used for comparisons. Mean biases (in situ minus satellite) are close to zero for wind speed and ‐2.7° for wind direction with a standard deviation of 1.2 m s  − 1 and 15°, respectively. The impact of using QuikSCAT and in situ measurements extrapolated to 10 m for wind power density estimations is assessed, accounting for possible influences of rain‐contaminated retrievals, the sample size, the atmospheric stability effects and either fitting the Weibull distribution or obtaining the estimates from the time series of wind speed observations.Copyright © 2012 John Wiley & Sons, Ltd.