bluuebunny/crossref_metadata_2025 huggingface dataset:
From the Editors' Desk
Authors: Pashinin Pavel P. , Yermachenko Valery M. , Manassah Jamal T. , Yevseyev Igor V.
Published: November 2006

Dear Colleagues,

With this issue, Laser Physics Letters enters its fourth
year of publication.

In our capacity as the Executive Committee of the
Editorial Board, we wish to thank, on behalf of ourselves and of
the other members of the Editorial Board, our many authors who
joined with us in shaping our journal in its first three formative
years.

Our goal continues to be the fast publication of the
results of quality research in Laser Sciences from leading
institutions from all around the world.

Some facts that may be of interest to both our authors
and readers, include the following:

1. The Journal has so far published articles from research groups located in 45 countries from five continents.
2. The acceptance rate for submitted manuscripts is 46%.
3. Through the marketing efforts of our publisher, Wiley-VCH, hard copies of the journal can now be found in the majority of leading institutional libraries worldwide.
4. The staff Editor and the Production team are web-posting all accepted manuscripts within 14 days of their submission date.
5. The Journal has now joined the ranks of standard Laser Sciences references. The Impact Factor for the Journal as reported by the Institute for Scientific Information is 1.225 for 2005.

While striving to maintain and/or improve on each of the
above benchmarks, our plans for the next phase are to:

1. Increase the yearly cap on our page budget from 600 to 900 pages.
2. Print on the cover of each issue a color figure from one of the included articles.
3. Add Graphical Abstracts at the beginning of each issue.
4. Reach out to distinguished research groups working in Laser Sciences and who have not so far joined the Journal Global Community as authors and/or readers.
5. Enlarge our rosters of editors and referees to expand our expertise and coverage of the continuously emerging new fields and sub-fields of Laser Sciences.

We seek your assistance in helping us achieve the above
goals. We welcome your suggestions for improving the quality of
our stewardship of the Journal.

Finally, we cannot let this opportunity pass without
congratulating John Wiley & Sons, the parent company of our
Publisher, Wiley-VCH, on its bicentennial celebration. The
Editorial Board and Astro Ltd. look forward for a continuing
successful and prosperous cooperative relationship with them in
the service of the Laser Physics Letters community.

Sincerely Yours,

Pavel P. Pashinin

Valery M. Yermachenko

Jamal T. Manassah

Igor V. Yevseyev
Anionic Polymerization of 1,3‐Cyclohexadiene: Reactivity of Poly(1,3‐cyclohexadienyl)lithium
Authors: Natori Itaru
Published: November 2006

Summary: The reactivity of poly(1,3‐cyclohexadienyl)lithium (PCHDLi), as a species for the propagation of the anionic polymerization of 1,3‐cyclohexadiene (1,3‐CHD), was examined using a post‐polymerization reaction of PCHDLi and 9‐bromofluorene (9‐BFL). The degree of nucleophilicity of the PCHDLi systems was determined as PCHDLi/1,4‐diazabicyclo[2,2,2]octane (DABCO) > PCHDLi/N,N,N′,N′‐tetramethylethylenediamine (TMEDA) > PCHDLi. The nucleophilicity of PCHDLi was strengthened by the complexation of TMEDA to Li, and was saturated when the TMEDA/Li molar ratio was over 1.0. The rate of polymerization increased with increasing nucleophilicity of PCHDLi. In addition, the molar ratio of the 1,2‐addition (1,2‐CHD unit)/1,4‐addition (1,4‐CHD unit) seemed to be strongly affected by both the nucleophilicity of PCHDLi and the steric hindrance of CLi bonds in PCHDLi.

Post‐polymerization reaction of poly(1,3‐cyclohexadienyl)lithium (PCHDLi) and 9‐bromofluorene (9‐BFL).

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Post‐polymerization reaction of poly(1,3‐cyclohexadienyl)lithium (PCHDLi) and 9‐bromofluorene (9‐BFL).
Polypeptide Modification of Multiwalled Carbon Nanotubes by a Graft‐From Approach
Authors: Yao Yuan , Li Wenwen , Wang Shoubai , Yan Deyue , Chen Xuesi
Published: November 2006

Summary: Covalent surface functionalization of carbon nanotubes with polypeptides is promising for possible medical applications. This work presents a graft‐from approach to perform the polypeptide modification of multiwalled carbon nanotubes (MWNTs). The raw MWNTs are first amine‐functionalized. The amine‐functionalized MWNTs are then used as the initiator to initiate the ring‐opening polymerization of γ‐benzyl‐L‐glutamate N‐carboxyanhydride (BLG‐NCA), to result in the polypeptide‐grafted MWNTs. FT‐IR, XPS, and TGA data demonstrate that the functionalization is successful. The TEM images of the products show that the thickness of the polypeptide shell of the PBLG‐MWNT is about 4.5–22 nm. Using the facile route developed here, carbon nanotubes functionalized with other types of polypeptides can be easily fabricated using the corresponding NCAs.

Strategy for the polypeptide modification of multiwalled carbon nanotubes by a graft‐from approach.

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Strategy for the polypeptide modification of multiwalled carbon nanotubes by a graft‐from approach.
Polystyrene Microspheres and Nanospheres Produced by Electrospray
Authors: Fantini Diego , Zanetti Marco , Costa Luigi
Published: November 2006

Summary: Polystyrene (PS) micro‐ and nanospheres with uniform dimensions and smooth surfaces have been produced by electrospray. The effect of PS molecular weight on beads morphology and the fundamental role of concentration have been investigated. Moreover, a new apparatus was designed to collect the polymer spheres during the process and to prevent the coalescence among the spheres.

PS micro‐ and nanospheres produced by electrospray

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PS micro‐ and nanospheres produced by electrospray
Long‐term tolerability of tetrabenazine in the treatment of hyperkinetic movement disorders
Authors: Kenney Christopher , Hunter Christine , Jankovic Joseph
Published: November 2006

We sought to review the long‐term tolerability of tetrabenazine (TBZ) and seek determinants of tolerability in the treatment of hyperkinetic movement disorders. A retrospective chart review was performed on patients treated with TBZ between 1997 and 2004. Efficacy of TBZ was assessed by a 1‐ to 5‐point response scale (1 = marked reduction in abnormal movements, 5 = worsening). All adverse events (AEs) were captured according to their relationship with study drug. A total of 448 patients (42% male) were treated for a variety of hyperkinesias, including tardive dyskinesia (n = 149), dystonia (n = 132), chorea (n = 98), tics (n = 92), and myoclonus (n = 19). The mean age at onset of the movement disorder was 43.0 ± 24.2 years, with TBZ starting at a mean age of 50.0 ± 22.3 years. Patients remained on treatment for a mean of 2.3 ± 3.4 years. An efficacy response rating of 1 or 2 was sustained in the majority of patients between the first and last visit. Common AEs included drowsiness (25.0%), Parkinsonism (15.4%), depression (7.6%), and akathisia (7.6%). Comparison of log‐likelihood ratios revealed that age was a reliable predictor of Parkinsonism (P< 0.0001). TBZ is a safe and effective drug for the long‐term treatment of hyperkinetic movement disorders. © 2006 Movement Disorder Society
Phenotypic variation among brothers with the McLeod neuroacanthocytosis syndrome
Authors: Walker Ruth H. , Jung Hans H. , Tison François , Lee Soohee , Danek Adrian
Published: November 2006

McLeod syndrome is an X‐linked multisystem disorder affecting red blood cells, the peripheral and central nervous systems, and skeletal and cardiac muscle. No clear correlations of the clinical findings with the genotype of XK mutations have yet been uncovered. Here, we report the clinical features and progression in 10 affected brothers from 4 families with McLeod syndrome. There is significant variation in clinical presentation within families, including in causes of morbidity and mortality. This phenotypic variation, despite shared mutations, suggests the action of disease‐modifying factors that may explain some of the difficulties with genotype–phenotype correlation in McLeod syndrome. © 2006 Movement Disorder Society
Substantia nigra hypoechogenicity: Definition and findings in restless legs syndrome
Authors: Godau Jana , Schweitzer Katherine J. , Liepelt Inga , Gerloff Christian , Berg Daniela
Published: November 2006

Pathological studies demonstrate a decreased iron content in the substantia nigra (SN) contributing to the pathophysiology of restless legs syndrome (RLS). SN echogenicity as measured by transcranial sonography (TCS) correlates with the SN iron content. The objective of this study was to determine a critical value to define SN hypoechogenicity as a potential marker for RLS. There were 49 RLS patients (39 idiopathic, 10 secondary) and 49 age‐ and sex‐matched controls who underwent TCS by 2 independent and blinded examiners to determine the area of SN echogenicity. We found that SN echogenicity is significantly decreased in RLS patients compared to healthy controls (P < 0.001). SN hypoechogenicity (sum area of SN echogenicity of both sides < 0.2 cm2) is more common in idiopathic than in secondary RLS patients. The area under curve for idiopathic RLS versus controls (receiver operating characteristics) is 0.91, specificity is 0.90, and sensitivity is 0.82. TCS provides an interesting additional instrument in the diagnosis of RLS. Therefore, SN hypoechogenicity (SN sum area < 0.2 cm2), which is supposed to indicate a decreased SN iron content, is a marker for RLS. Further studies are needed to investigate its significance for the pathophysiology of this frequent movement disorder and possible clinical applications. © 2006 Movement Disorder Society
Levodopa‐induced hyperactivity in mice treated with 1‐methyl‐4‐phenyl‐1,2,3,6‐tetrahydropyridine
Authors: Nicholas Anthony P.
Published: November 2006

The present study examines the motor responses of 10‐ to 12‐month‐old, male C57 mice that were either given intraperitoneal (IP) injections of 1‐methyl‐4‐phenyl‐1,2,3,6‐tetrahydropyridine (MPTP; 30 mg/kg per day) or vehicle for 10 consecutive days, followed by IP injections of levodopa (200 mg/kg) plus carbidopa (25 mg/kg). Five days of MPTP exposure resulted in the Straub tail phenomenon and pronounced hypokinesia. However, during the next 5 days, motor activity returned to baseline, even with continued MPTP treatment. After 10 to 14 days of rest, all mice were then treated with levodopa/carbidopa twice daily for multiple, consecutive days. However, only the previously MPTP‐treated animals became hyperkinetic, as compared to levodopa‐treated control animals that were not previously exposed to MPTP. Abnormal activity included scratching, running, gnawing, and jumping movements. Hyperactivity lasted for approximately 2 hours after each levodopa injection and then returned to baseline, but the amount of hyperkinesia increased with additional days of levodopa treatment, even though the daily levodopa dose was not changed. These results demonstrate that levodopa can cause reproducible hyperactivity in mice that were previously exposed to MPTP. © 2006 Movement Disorder Society
Mixed alien hand syndrome coexisting with left‐sided extinction secondary to a left corpus callosal lesion: A case report
Authors: Lin Ji‐Ho , Kwan Shang‐Yeong , Wu Dean
Published: November 2006

Alien hand syndrome (AHS) is actually two distinct syndromes with distinct clinical and anatomic features, that is, a frontal type and a callosal type. Frontal AHS occurs in the dominant hand; is associated with reflexive grasping, groping, and compulsive manipulation of tools. Callosal AHS is characterized primarily by intermanual conflict. We report a case of right frontal AHS and left callosal AHS (mixed AHS) secondary to ischemic stroke of the left corpus callosum (lesion extending from the genu to splenium) and right corpus callosum (minimal lesion in the splenium) in a 67‐year‐old male patient who also presented with left‐sided tactile extinction. To our knowledge, rare reports have documented mixed AHS coexisting with nondominant side extinction secondary only to unilateral (left) callosal lesion, as in our case. © 2006 Movement Disorder Society
Abnormal responses to repetitive transcranial magnetic stimulation in multiple system atrophy
Authors: Löscher Wolfgang N. , Stampfer‐Kountchev Michaela , Sawires Martin , Seppi Klaus , Mueller Joerg , Szubski Christoph , Hirnsperger Katrin , Brenneis Christian , Poewe Werner , Wenning Gregor K.
Published: November 2006

We studied the response of the motor cortex to brief trains of suprathreshold repetitive transcranial magnetic stimulations (rTMS) in patients with the Parkinson‐variant of multiple system atrophy (MSA‐P) and compared it to patients with idiopathic Parkinson's disease (PD) and healthy controls. Eight subjects were studied in each group, and patients were matched for disease severity as assessed by Hoehn & Yahr stages. rTMS was delivered at rest and during low‐level contractions in trains of 10 stimulations at 5 Hz, and stimulation intensity was set to result in an motor evoked potential (MEP) in the first dorsal interosseus muscle of 0.5 to 1.0 mV. In MSA‐P, MEP amplitude at rest was already reduced after the second stimulus and remained so, while it did not change in PD and controls. During contraction, MEP size did not change during the train in any group. The silent period that followed the last stimulus was of similar duration as the first stimulus in MSA‐P, but was increased in PD and controls. These findings indicate that abnormal inhibition occurs within the motor cortex in MSA‐P, despite dopaminergic treatment and indicate differences in cortical dysfunction between MSA‐P and PD. We suggest that these abnormalities reflect the motor cortex pathology found in MSA‐P. © 2006 Movement Disorder Society
Retracted: Unsteady flow and heat transfer on a rotating disk in a porous medium
Authors: Attia Hazem Ali
Published: November 2006

This article has been retracted. See retraction notice DOI:10.1002/mma.850. An unsteady flow and heat transfer in a porous medium of a viscous incompressible fluid over a rotating disk in an otherwise ambient fluid are studied. The unsteadiness in the flow field is caused by the angular velocity of the disk which varies with time. The new self‐similar solution of the Navier–Stokes and energy equations is obtained numerically. The solution obtained here is not only the solution of the Navier–Stokes equations, but also of the boundary layer equations. Also, for a simple scaling factor, it represents the solution of the flow and heat transfer in the forward stagnation‐point region of a rotating sphere or over a rotating cone. The asymptotic behaviour of the solution for a large porosity or for a large independent variable is also examined. The surface shear stresses in the radial and tangential directions and the surface heat transfer increase as the acceleration parameter increases. Also, the surface shear stress in the radial direction and the surface heat transfer decrease with increasing porosity, but the surface shear stress in the tangential direction increases. Copyright © 2006 John Wiley & Sons, Ltd.
Dynamic and generalized Wentzell node conditions for network equations
Authors: Mugnolo Delio , Romanelli Silvia
Published: November 2006

Motivated by a neurobiological problem, we discuss a class of diffusion problems on a network. The celebrated Rall lumped soma model for the spread of electrical potential in a dendritical tree prescribes that the common cable equation must be coupled with particular dynamic conditions in some nodes (the cell bodies, or somata). We discuss the extension of this model to the case of a whole network of neurons, where the ramification nodes can be either active (with excitatory time‐dependent boundary conditions) or passive (where no dynamics take place, i.e. only Kirchhoff laws are imposed). While well‐posedness of the system has already been obtained in previous works, using abstract tools based on variational methods and semigroup theory we are able to prove several qualitative properties, including asymptotic behaviour, regularity of solutions, and monotonicity of the semigroups in dependence on the physical coefficients. Copyright © 2006 John Wiley & Sons, Ltd.
Toxicity of the AGEs generated from the Maillard reaction: On the relationship of food‐AGEs and biological‐AGEs
Authors: Van Nguyen Chuyen
Published: November 2006

Advanced glycation end products (AGEs) are generated in the late stages of Maillard reaction in foods and biological systems. These products are mostly formed by the reactions of reducing sugar or degradation products of carbohydrates, lipids, and ascorbic acid. AGEs exist in high concentration in foods, but in relatively low concentrations in most of the biological systems. Recently, some AGEs have been reported to be toxic, and were proposed to be causative factors for various kinds of diseases, especially diabetes and kidney disorder, through the association with receptor of AGE (RAGE). It has also been reported that food‐derived AGEs (food‐AGEs) may not be a causative factor for pro‐oxidation. However, the relationship of food‐AGEs and biological‐derived AGEs (biological‐AGEs) is not clear. In this review, the following issues are discussed: the formation of AGEs in foods and biological systems; identification of the main AGEs in foods and biological systems; absorption of food‐AGEs; the effects of AGEs in vivo; relationship between food‐AGEs and biological‐AGEs; possible defense mechanism against AGEs in vivo and finally, the problems to be solved concerning the toxicity of AGEs.
Quantitative protein analysis from formalin‐fixed tissues: implications for translational clinical research and nanoscale molecular diagnosis
Authors: Becker K‐F , Schott C , Hipp S , Metzger V , Porschewski P , Beck R , Nährig J , Becker I , Höfler H
Published: November 2006

Owing to its cross‐linking effects, it is currently believed that formalin fixation of routinely processed tissues in the clinic prevents protein extraction and profiling. The aim of our study was to develop a robust, fast, standardized, and easy to use technique for the solubilization of non‐degraded, full length, and immunoreactive proteins from formalin‐fixed tissues for western blot and protein microarray analysis. Sections of routinely processed formalin‐fixed and paraffin‐embedded tissues of various origin were analysed. After deparaffination, tissues were manually dissected from the slides and transferred into an optimized protein extraction buffer system. Proteins were solubilized and subsequently analysed by western blot and reverse phase protein microarrays. We succeeded in isolating non‐degraded, soluble, and immunoreactive proteins from routinely processed formalin‐fixed tissues. We were able to detect membrane, cytoplasmic and nuclear proteins at the expected molecular weight. No differences were found in the protein yield and protein abundances between fresh frozen and formalin‐fixed tissues. Using western blots and reverse phase protein microarrays, the receptor tyrosine kinase HER2, an important protein target for antibody based cancer treatment, was reliably measured in formalin‐fixed breast cancer biopsy samples when compared with measurement by immunohistochemistry and fluorescence in situ hybridization; remarkably, immunohistochemically equivocal cases (score 2 + ) can be categorized according to HER2 protein abundance. Our new clinically orientated multiplexed protein measurement system may be generally applicable to determine the relative abundances of known disease‐related proteins in small amounts of routinely processed formalin‐fixed tissue samples for research and diagnosis. This technique may also be used to identify, characterize, and validate known and new protein markers in a variety of human diseases. Copyright © 2006 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Developing interprofessional working in primary care
Authors: Fear Tina , de Renzie‐Brett Helen
Published: November 2006

Interprofessional working is a key feature of current UK health care policy. A primary care trust saw an opportunity to develop a new general practice service to meet the needs of an inner‐city population. Academics from the University of the West of England, Bristol, acted as facilitators, to assist the practice team.

This paper discusses the development of an interprofessional team establishing new ways of working with a diverse practice population. It illustrates the challenges and achievements of the team as its members strived to attain interprofessional working. A project evaluation revealed the learning, challenges and changes in practice that were achieved. It also suggests a model of working that is transferable to other workplaces. Copyright © 2006 John Wiley & Son, Ltd.
The development of advanced practice roles in ophthalmic nursing
Authors: Marsden Janet , Shaw Mary E
Published: November 2006

Advanced practice roles in ophthalmic settings have enabled the delivery of the policy agenda with high quality outcomes. This paper reports on a study undertaken to provide a ‘snapshot’ of such roles. It was found that while roles are diverse and continue to respond to service need, ophthalmologists, rather than nurses, control many of the parameters of the role and undertake much of the training and assessment. All nurses in this study undertook in‐house training rather than education for their roles and none was able to be supernumerary which, in some cases, delayed service development. It is suggested that nursing administration must recognise the need for education as well as training and advocate for it in order that roles may be developed effectively and systematically. Copyright © 2006 John Wiley & Sons, Ltd.
Changing trends in sex specific prevalence rates for childhood asthma, eczema, and hay fever
Authors: Osman Mustafa , Tagiyeva Nara , Wassall Heather J. , Ninan Titus K. , Devenny Anne M. , McNeill Geraldine , Helms Peter J. , Russell George
Published: November 2006

Numerous surveys of school‐aged children have shown increasing asthma prevalence with a less publicized but noticeable change in the male to female ratio. We sought to confirm this change in the sex ratio in four questionnaire‐based surveys and investigate possible explanations. Identical questionnaire surveys were performed in 1989 (n = 3,390), 1994 (n = 4,047), 1999 (n = 3,540) and 2004 (n = 1,920) in school‐children aged 9–11 years. Over these 15 years the male to female ratio (M:F) significantly narrowed for wheeze (1.34 to 0.98:1 P < 0.0002), for asthma (1.74 to 1.02:1 P < 0.0001), for eczema (1.42:1 to 0.81:1 P < 0.0001) and for hay fever (1.46 to 0.93:1 P < 0.0001). The diagnosis of asthma in children with wheeze was more commonly made in boys in 1989 relative risk RR 1.32 (1.12, 1.56), even in those with accompanying eczema and/or hay fever RR 1.20 (0.99, 1.45). By 2004 this sex bias in diagnosis was no longer present, RR 1.01 (0.91, 1.12) for wheeze and 1.02 (0.85, 1.21) for those with wheeze and eczema and/or hay fever. From 1989 to 2004 no significant difference in sex distribution changes between older and younger children occurred, making secular trends in the onset of puberty in females an unlikely contributory factor. The disappearance of the bias to diagnose asthma in symptomatic males but not in females may be partly responsible for the narrowing of the sex ratio, but other factors such as those enhancing the expression of asthma and atopy in females may also be implicated. Pediatr Pulmonol. 2007; 42:60–65. © 2006 Wiley‐Liss, Inc.
Interplay of electrostatic and van der Waals forces in coronene dimer
Authors: Obolensky O. I. , Semenikhina V. V. , Solov'yov A. V. , Greiner W.
Published: November 2006

Interplay of electrostatic and van der Waals forces in the coronene dimer is studied. Our results show that the lowest‐energy configuration of the dimer is not necessarily a stack, as it might had been expected a priori. This is a surprising result for the dimer of such a large polycyclic aromatic hydrocarbon (PAH) as coronene (C24H12). The energy of the T‐shaped configuration at all highest feasible levels of density functional theory (DFT) (B3LYP, PBE/6‐31+G(d), D95, cc‐pVDZ, cc‐pVTZ) is lower than the energies of the three plausible stack configurations. To get a better description of the van der Waals interaction, the DFT results were corrected by a phenomenological van der Waals‐type term. This correction gives a slight edge to the parallel‐displaced stack configuration. However, the magnitude of the correction is somewhat arbitrary, depending on the set of parameters used. This makes the definitive conclusion impossible at the currently achievable level of theory. A simple model is proposed that is useful for the qualitative understanding of possible geometries of the coronene dimer and larger coronene clusters. The model represents the coronene dimer as two sets of charged rings interacting via Coulomb and Lennard‐Jones potentials. The model provides an intuitively clear explanation as to why the T‐shaped dimers can be of importance even for some of moderately large PAHs such as coronene, and perhaps for circumcoronene as well. The unexpectedly strong competitiveness of the T‐shaped configuration is connected to the round shape of the coronene molecules. Indeed, rotation or parallel displacement of the non‐round monomers result in significantly smaller Coulomb repulsion as compared with the “face‐to‐face” sandwich configurations. In contrast, for the stacked round molecules rotation and/or displacement are much less effective. Therefore, the round shape of the coronenes leads to an increased role of the electrostatic repulsion in the stack configurations. The proposed model can easily be generalized to other PAH, DNA bases, etc. © 2006 Wiley Periodicals, Inc. Int J Quantum Chem, 2007
Double hexagonal chains with maximal energy
Authors: Ren Haizhen , Zhang Fuji
Published: November 2006

The ground state electron energy of neutral alternant conjugated hydrocarbons has an absolute value that may be identified as the sum of the absolute values of all the electron eigenvalues of its corresponding graph. The “double hexagonal chains” can be considered as benzenoids constructed by successive fusions of naphthalenes along a zig‐zag sequence of triples of edges as appear on opposite sides of each naphthalene unit. We show that if the fusions give an all‐kink structure (e.g., polybiphenanthrene), then the total π‐electron energy is the maximum from among all the double hexagonal chains with the same number of naphthalene units. © 2006 Wiley Periodicals, Inc. Int J Quantum Chem, 2007
Calculation of iodine value from measurements of fatty acid methyl esters of some oils: Comparison with the relevant American Oil Chemists Society method
Authors: Kyriakidis Nikolaos B. , Katsiloulis Theophanis
Published: November 2006

A new calculation method for the determination of iodine value (IV) from measurements of fatty acid methyl esters is proposed. The method is based on the quantitative determination of fatty acid methyl esters of vegetable oils by capillary gas chromatography. IV is a measure of the number of double bonds in the unsaturated fatty acids in one gram of oil. The analytical methodology of its evaluation includes the use of rather health dangerous reagents, and for that reason is mostly avoided by laboratory analysts. A calculation procedure to determine the IV of oils from their fatty acid methyl ester composition is in use based on the American Oil Chemists’ Society (AOCS) method Cd 1c‐85. A new calculation procedure for IV, based also on the evaluation of the fatty acid methyl esters of oils, was developed. The application of the proposed calculation methodology was checked with olive oil, corn oil, soybean oil, cottonseed oil, and sunflower seed oil. The proposed calculation gave results in better agreement with the Wijs method than with the relevant AOCS method.
Continuous production of palm methyl esters
Authors: Darnoko D. , Cheryan Munir
Published: November 2006

A system for continuous transesterification of palm oil was developed using a continuous stirred‐tank reactor (CSTR) and pumps for continuous delivery of oil and catalyst and for continuous removal of product. Potassium hydroxide was used as the catalyst, the methanol‐to‐oil molar ratio was 6∶1, and reaction temperature was 60°C. The yield of methyl esters increased from 58.8% of theoretical yield at a residence time of 40 min to 97.3% at a residence time of 60 min. However, higher residence times decreased the production rate. During long‐term continuous operation, the CSTR displayed steady state conditions in terms of product profile and methyl ester concentration. This process has good potential in the manufacture of biodiesel.
Evaluation of different types of synthetic adsorbents for carotene extraction from crude palm oil
Authors: Latip R. A. , Baharin B. S. , Che Man Y. B. , Abdul Rahman R.
Published: November 2006

Palm carotene was successfully concentrated from crude palm oil (CPO) by an adsorption process using synthetic adsorbents followed by solvent extraction. This process was a modified process for separation of palm carotene from CPO by adsorption chromatography with a synthetic polymer adsorbent. Carotene was concentrated to about 15,000 ppm, which is about 25 times the original concentration in CPO. Carotene recovery varied from 30 to 62% depending on the process conditions. Different types of adsorbents, combinations of adsorbents, and adsorbent/CPO ratios were evaluated to determine the effect on the percentage of carotene extracted. Commercial synthetic adsorbents HP 20 (styrene‐divinyl copolymer); synthetic aromatic porous resin SP 850, SP 825; and synthetic adsorbents Relite Exa 32 and Relite Exa 50 were capable of adsorbing substantial amounts of carotene from CPO. Combinations of adsorbents types HP 20 and SP 850 slightly increased the percentage of carotene extracted. An adsorbent/CPO ratio of 4 was most suitable for this process for optimal recovery and concentration of carotene.
A new method for determining aflatoxins in groundnut and groundnut cake using fourier transform infrared spectroscopy with attenuated total reflectance
Authors: Mirghani M. E. S. , Che Man Y. B. , Jinap S. , Baharin B. S. , Bakar J.
Published: November 2006

A new analytical method was developed for the determination of aflatoxins in groundnut and groundnut cakes by Fourier transform infrared (FTIR) spectroscopy using horizontal attenuated total reflectance technique. Groundnut and groundnut cake samples were used in this study. The wave‐lengths were selected for the four types of aflatoxins—B1, B2, G1, and G2—and the standards prepared for earch by spiking some clean sample with the aflatoxins in concentrations of 0–1200 parts per billion. A partial least square regression was used to derive the calibration models for each toxin. The coefficients of determination (R2) of the calibration model were computed for the FTIR spectroscopy predicted values vs. actual values of aflatoxins in parts per billion. The R2 was found to be 0.9911, 0.9859, 0.9986, and 0.9789 for aflatoxins B1, B2, G1 and G2, respectively. Standard errors of calibration for groundnut samples were found to be 1.80, 2.03, 1.42, and 2.05 for aflatoxins B1, B2, G1, and G2, respectively. Calibration models were validated with an independent set of samples. The R2 of validation models were computed. The SD of the difference for repeatability of the FTIR method was found to be better than that of the chemical method. Based on the results obtained, FTIR spectroscopy can be a useful instrumental method for determining aflatoxins in oilseeds and oilseed cakes. With its speed and ease of data manipulation by computer software, it is a possible alternative to the standard wet chemical methods for a rapid and accurate routine determination of aflatoxin levels in food and feed.
A modified method for the estimation of total carbonyl compounds in heated and frying oils using 2‐propanol as a solvent
Authors: Endo Yasushi , Li Chang Mo , Tagiri‐Endo Misako , Fujimoto Kenshiro
Published: November 2006

A modified method without using benzene for quantitative determination of total carbonyl compounds in heated and frying fats and oils has been developed. The analysis is done by the reaction of 2,4‐dinitrophenylhydrazine (2,4‐DNP) with aldehydes and ketones in 2‐propanol. The optimal wavelength to determine the total carbonyl compounds is 420 nm where the 2,4‐dinitrophenylhydrazone (2,4‐DNPH) derivatives from saturated and unsaturated aldehydes and ketones had the same molar absorption coefficient. The modified method for the estimation of total carbonyl compounds in heated and frying oils using 2‐propanol instead of benzene as a solvent had a good correlation with the conventional method.
Deterpenation of Brazilian orange peel oil by vacuum distillation
Authors: Stuart Giane R. , Lopes Daíse , Oliveira J. Vladimir
Published: November 2006

The deterpenation of orange peel oil in most industries is accomplished by vacuum distillation, but surprisingly little information on this matter can be found in the open literature. This work reports recent results on orange peel oil deterpenation carried out in an automatic vacuum distillation column operated in the semibatch mode at the temperatures of 50, 65, and 80°C, at 10, 20, and 30 mbar, and with reflux ratios of 0.25, 0.50, and 0.75. The concentrates were analyzed with regard to the oxygenate compound content by gas chromatography coupled with a mass spectrometer (GC‐MS) and evaluated by sensory analysis, and also with regard to the aldehyde content. As one could expect, there is a strong relationship between oil quality, as revealed by the sensory analysis, and chemical composition, as determined by GC‐MS. The concentration factor and process yield, as expressed by “fold,” together with the analysis results show that it is possible to obtain high quality concentrates simply by manipulating the operating variables in the vacuum fractionation process.
Classification of vegetable oils by high‐resolution 13C NMR spectroscopy using chromatographically obtained oil fractions
Authors: Zamora Rosario , Gómez Gemma , Hidalgo Francisco J.
Published: November 2006

13C NMR spectra of oil fractions obtained chromatographically from 109 vegetable oils were obtained and analyzed to evaluate the potential use of those fractions in the classification of vegetable oils and to compare the results with the NMR analysis of complete oils. The oils included the following: virgin olive oils from different cultivars and regions of Europe and north Africa; “lampante” olive, refined olive, refined olive pomace, hazelnut, rapeseed, high‐oleic sunflower, corn, grapeseed, soybean, and sunflower oils; and mixtures of virgin olive oils from different geographical origins. Oils were divided into two sets of samples. The training set (98 samples) was employed to select the variables that resulted in significant discrimination among the different oil classes. By using stepwise discriminant analysis, more than 98% of correct validated assignments were obtained; these results were confirmed when applied to the test set (11 blind samples). Results suggest that the use of oil fractions considerably increases the discriminating power of NMR in the analysis of vegetable oils.
Effect of female and male genotypes and environment on wax composition in jojoba
Authors: Benzioni Aliza , Vaknin Yiftach
Published: November 2006

The objective of this study was to determine the effects of genotype and environment on wax composition in jojoba seed, and thus be able to control it. Production of waxes with different compositions—and hence changed wax properties such as viscosity, boiling point, and thermal stability—may be of importance for future requirements of the jojoba industry. Wax composition of 23 female clones was determined for two growing seasons. The ratio of FA elongated to the sum of those reduced and esterified differed among genotypes, resulting in differences in the percentage of wax esters longer than 40 or 42 carbons. The clones ‘Yarden,’ ‘Gvati’, ‘Hazerim,’ ‘BGU,’ and ‘Negev’ had higher percentages of long‐chain wax moieties than the clones ‘879–154’, ‘MS 55–4’, and ‘Forti.’ The contribution of the male genotype to wax composition was tested by pollinating bagged female flowers of four female clones with pollen from three male plants. Both male and female genotypes additively influenced the composition of the wax esters. Wax composition varied between growing seasons and locations, but differences between genotypes were consistent. Salinity of the irrigation water did affect wax composition in some clones. Under high salinity, the salt‐sensitive clone ‘64’ produced a smaller percentage of long‐chain wax esters, whereas in clone ‘Q‐106’ wax composition did not change. In clone ‘874–154’ the chain lengths of the wax moieties in the seeds increased under medium salinity. We conclude that jojoba wax composition is influenced by both female and male genotypes and by environmental factors such as climate and salinity.
Comparison of four analytical methods for the determination of peroxide value in oxidized soybean oils
Authors: Yildiz Gülgün , Wehling Randy L. , Cuppett Susan L.
Published: November 2006

Previous work in our laboratory demonstrated that soybean oil oxidation, expressed as PV, can be determined using NIR transmission spectroscopy as an alternative to the official AOCS iodometric titration method. In the present study, a comparison of four peroxide analytical methods was conducted using oxidized soybean oil. The methods included the official AOCS iodometric titration, the newly developed NIR method, the PeroxySafe™ kit, and a ferrous xylenol orange (FOX) method, the latter two being colorimetric methods based on oxidation of iron. Five different commercially available soybean oils were exposed to fluorescent light to obtain PV levels of 0–20 meq/kg; periodic sampling was done to ensure having representative samples throughout the designated range. A total of 46 oil samples were analyzed. Statistical analysis of the data showed that the correlation coefficient (r) and standard deviation of differences (SDD) between the standard titration and NIR methods were r=0.991, SDD=0.72 meq/kg; between titration and the PeroxySafe™ kit were r=0.993, SDD=0.56 meq/kg; and between the standard titration and FOX method were r=0.975, SDD=2.3 meq/kg. The high correlations between the titration, NIR, and PeroxySafe™ kit data indicated that these methods were equivalent.
How green is green? Long‐term relationships between green seeds and chlorophyll in canola grading
Authors: Daun James K.
Published: November 2006

Chlorophyll is undesirable in canola seeds because it is extracted into the oil resulting in problems during processing and utilization. In the Canadian grain grading system, and in similar systems in use in the United States and Australia, chlorophyll is estimated in canola seeds subjectively by crushing and counting the number of distinctly green seeds in a sample while simultaneously assessing the overall natural color of the crushed seeds. Chlorophyll contents of canola may be determined by extraction with solvent followed by spectrophotometric analysis or by using NIR instrumentation, capable of operating in the visible region and calibrated against samples with known amounts of chlorophyll. The relationship between the green seeds and chlorophyll content in canola export shipments from 1988 to 2001 was found to be linear. The intercept, referred to as the background chlorophyll, ranged from 6 to 16 mg/kg, and the slope ranged from 300 to 1000 mg/kg per green seed. In recent years, both the background chlorophyll and the slope have been increasing, resulting in an increase in the chlorophyll levels in top‐grade canola exported from Canada. The increase may be partly a result of the change in proportion of species of canola grown in Canada, and also may result from changes in perception of what constitutes a green seed. The use of an objective measurement of chlorophyll is recommended to improve the consistency of the grading system.
Study on synthesis parameters of lipase‐catalyzed hexyl acetate in supercritical CO2 by response surface methodology
Authors: Yu Zer‐Ran , Chang Shu‐Wei , Wang Hao‐Yu , Shieh Chwen‐Jen
Published: November 2006

Hexyl acetate, a short‐chain ester with fruity odor, is a significant green note flavor compound that is widely used in the food industry. The ability of immobilized lipase from Rhizomucor miehei (Lipozyme IM‐77) to catalyze the transesterification of hexanol with triacetin in supercritical carbon dioxide was investigated in this study. Response surface methodology and a 3‐level‐3‐factor fractional factorial design were adopted to evaluate the effects of synthesis variables, such as reaction time (30 to 90 min), temperature (35 to 55°C), and pressure (1500 to 3500 psi), on percent molar conversion of hexyl acetate. The results showed that reaction time and pressure were the most important parameters and temperature had less effect on percent molar conversion. Based on canonical analysis, optimal synthesis conditions were as follows: reaction time 69.0 min, synthesis temperature 46.7°C, pressure 2640 psi. The predicted value was 75.6% and the actual value was 77.3% molar conversion.
Biosynthesis of tetrahydrofuranyl fatty acids from linoleic acid by clavibacter sp. ALA2
Authors: Hosokawa M. , Hou C. T. , Weisleder D. , Brown W.
Published: November 2006

Clavibacter sp. ALA2 converts linoleic acid into many novel oxygenated products including hydroxy FA and tetrahydrofuranyl unsaturated FA (THFA). One of them was tentatively identified by GC‐MS as 12,13,16‐trihydroxy‐9(Z)‐octadecenoic acid (12,13,16‐THOA) (Hou, C.T., H.W. Gardner, and W. Brown, J Am. Oil Chem. Soc. 78∶1167–1169, 2001). We have separated and purified 12,13,16‐THOA from its isomer, 12,13,17‐THOA, by silica gel column chromatography and by preparative TLC. Its structure was then confirmed by proton and 13C NMR analyses. Purified 12,13,16‐THOA was used as a substrate to study the biosynthesis of THFA. Within 24 h of incubation, cells of strain ALA2 converted 12,13,16‐THOA to both 12‐hydroxy‐13,16‐epoxy‐9(Z)‐octadecenoic acid (12‐hydroxy‐THFA) and 7,12‐dihydroxy‐13,16‐epoxy‐9(Z)‐octadecenoic acid (7,12‐dihydroxy‐THFA). The relative abundance of 7,12‐dihydroxy‐THFA increased with incubation time, whereas that of 12,13,16‐THOA and of 12‐hydroxy‐THFA decreased. Therefore, the biosynthetic pathway of THFA from linoleic acid by strain ALA2 is as follows: linoleic acid→12,13‐dihydroxy‐9(Z)‐octadecenoic acid→12,13,16‐THOA→12‐hydroxy‐THEA→7,12‐dihydroxy‐THFA.
Relationship between rancimat and active oxygen method values at varying temperatures for several oils and fats
Authors: Anwar Farooq , Bhanger M. I. , Kazi T. G.
Published: November 2006

Determination of oxidative stability of different edible oils, fats, and typical fat products was made using the Rancimat method and the active oxygen method. Induction periods (IP) were recorded under controlled conditions at 110, 120, and 130 ± 0.1°C for all products and over a range of 100–160°C for selected fats. A general oil stability evaluation industrial shortenings and vanaspati to be the most stable fats, with IP ranging from 10.00 to 15.47 h. Margarine and butter samples (IP, 4.98–6.04 h) were also found to show fair oxidative stability. Among the extracted and open‐market salad‐grade cooking oils, rapeseed oil (IP, 4.10 h) and soybean oil (IP, 4.00 h) showed the highest oxidative stability, whereas Salicornia bigelovii oil (IP, 1.40 h) was the least stable. The induction periods of typical fat products ranged from 2.59 to 9.20 h. CV for four determinations were <5.2% for shortening and vanaspati products and <4.3% for various vegetable oils, margarine, butter, and typical fat products. Rancimat IP values obtained at 110, 120, and 130°C were 40–46, 20–25, and 9–13% of active oxygen method values, respectively, corresponding to a decrease in Rancimat IP by a factor of 1.99 with each 10°C increase in temperature. Similarly, in the temperature range 100–160°C, an increase of 10°C decreased the Rancimat IP by a factor of 1.99
Extraction of wheat germ oil by supercritical CO2: Oil and defatted cake characterization
Authors: Panfili G. , Cinquanta L. , Fratianni A. , Cubadda R.
Published: November 2006

In this paper the working conditions for the extraction of wheat germ oil in a supercritical CO2 pilot plant of 1‐L‐extraction capacity were studied. The best conditions were: pressure, 38 MPa; temperature, 55°C; wheat germ particle size, about 0.35 mm; CO2 flow rate, 1.5 L min−1. These conditions gave yields of about 92% of total oil after 3 h of processing. The obtained oils and the partially defatted cake were investigated with regard to their FA, tocol (tocopherol and tocotrienol), carotenoid, and sterol compositions and to their quality characteristics (FFA, PV, para‐anisidine value, and color of the by product). Moreover, the oil quality was evaluated in relation to the progress of the supercritical extraction.
Oxidative and flavor stabilities of soybean oils with low‐and ultra‐low‐linolenic acid composition
Authors: Su Caiping , Gupta Monoj , White Pamela
Published: November 2006

The effects of linolenic acid (18∶3) concentration, combined with TBHQ addition, temperature, and storage time, on the oxidative and flavor stabilities of soybean oils (SBO) were evaluated. During storage under fluorescent light at both 21 and 32°C, the SBO with ultra‐low‐18∶3 concentration (1.0%, ULSBO) generally had greater oxidative stability than did SBO with low‐18∶3 concentration (2.2%, LLSBO). The ULSBO had about half the p‐anisidine value of LLSBO throughout storage. Although the ULSBO initially had significantly greater PV and poorer (lower) sensory scores for overall flavor quality than did LLSBO, significant differences disappeared with storage. The ULSBO had a lower content of polar compounds and greater oil stability indices than did LLSBO when TBHQ was present. All oils were more oxidatively stable with TBHQ addition, but the TBHQ addition did not result in improved flavor stability early in storage. In all tests, oils stored at 32°C were less stable than oils stored at 21°C. The TBHQ had a better antioxidant capacity when the 18∶3 concentration was lower. The retardation effect of TBHQ on lipid oxidation and the improved stability of ULSBO over LLSBO were more easily detected when the storage temperature was higher.
Oxidation of soybean oil during storage of starch‐oil composites
Authors: Garzón G. A. , Warner K. , Felker F. C. , Palmquist D. E. , Eller F.
Published: November 2006

The oxidative deterioration of dry starch‐oil composites was investigated by chemical and sensory methods. The composites were stored at 37°C for 63 d, and changes in the hexanal content and odor attributes were monitored. Analysis of the extracted oil showed that the first run through the drum dryer presented higher hexanal concentrations than the subsequent runs. Starch‐oil composites from the first run though the drum dryer showed higher metal concentrations and higher odor ratings during storage time than the subsequent runs. There was a significant correlation between odor attributes and hexanal concentration in the first run. Since both the oxidation and the metal content were higher in the first run and decreased in further runs, we concluded that oxidation might have been induced by the presence of metal in the drum dryer. It is likely that during drum drying, the metal drum and knife surfaces became coated with soy oil, reducing both abrasion and metal contact with the product. Since many applications of the starch‐oil composite technology require drum drying, it will be necessary to take measures to minimize metal contamination of the product, perhaps by discarding the initial portion of product, which contains the most metal.