bluuebunny/crossref_metadata_2025 huggingface dataset:
Internal model principle‐based control of exponentially damped sinusoids
Authors: Lu J. , Brown L. J.
Published: May 2009

An internal model principle‐based adaptive algorithm for identifying and canceling disturbances composed of sums of exponentially damped sinusoidal (EDS) signals is presented. The state variables of an internal model principle controller in a feedback loop can provide estimates of the EDS signal parameters, the frequency and the damping factor. By using additional integral controllers, the parameter errors can be eliminated to achieve perfect cancelation. The convergence of the proposed adaptive algorithm and the stability of the feedback control system adopting the algorithm are justified using singular perturbation theory and averaging theory. Simulation results demonstrate the performance of the algorithm. Copyright © 2009 John Wiley & Sons, Ltd.
Phase II study of bryostatin 1 and vincristine for aggressive non‐Hodgkin lymphoma relapsing after an autologous stem cell transplant
Authors: Barr Paul M. , Lazarus Hillard M. , Cooper Brenda W. , Schluchter Mark D. , Panneerselvam Ashok , Jacobberger James W. , Hsu Jack W. , Janakiraman Nalini , Simic Aleksandra , Dowlati Afshin , Remick Scot C.
Published: May 2009

Bryostatin 1, isolated from a marine bryozoan, enhances the efficacy of cytotoxic agents through modulation of the protein kinase C pathway and is active in combination with vincristine for diffuse large B‐cell lymphoma. Further, the apoptotic frequency of peripheral blood T lymphocytes as determined by flow cytometry may predict which patients will respond to this combination. We tested the efficacy and safety of bryostatin 1 50 μg/m2 given over 24 hr and vincristine 1.4 mg/m2 on days 1 and 15 every 28 days in aggressive B‐cell non‐Hodgkin lymphoma (NHL) relapsing after autologous stem cell transplantation. End points included tumor response, toxicity, and survival. Responses were correlated with an increase in apoptotic frequency of CD5+ cells by flow cytometry using annexin V staining. Fourteen patients were enrolled with 13 being evaluable for a response. The overall response rate was 31% with two patients achieving a complete response. The most common toxicities were Grade 3 lymphopenia (seven patients), Grade 3 to 4 neutropenia (two patients), and Grade 3 hypophosphatemia (two patients). Median progression‐free and overall survivals for all patients were 5.7 and 21.4 months, respectively. One patient demonstrated an increase in T‐cell apoptotic frequency, also achieving a complete response. Bryostatin 1 and vincristine have efficacy in select patients with aggressive NHL. Future investigations of agents targeting the protein kinase C pathway may benefit from early response assessment using flow cytometry to evaluate T‐cell apoptosis. Am. J. Hematol., 2009. © 2009 Wiley‐Liss, Inc.
Differences in diet and activity pattern between two groups ofAlouatta palliataassociated with the availability of big trees and fruit of top food taxa
Authors: Dunn Jacob C. , Cristóbal‐Azkarate Jurgi , Veà Joaquím J.
Published: May 2009

The threat that forest fragmentation and habitat loss presents for severalAlouattataxa requires us to determine the key elements that may promote the persistence of howler monkeys in forest fragments and to evaluate how changes in the availability of these elements may affect their future conservation prospects. In this study we analyzed the relationship between the availability of both big trees of top food taxa (BTTFT) (diameter at breast height>60) and fruit of top food taxa (FrTFT) in the home ranges of two groups ofAlouatta palliata mexicanaoccupying different forest fragments in Los Tuxtlas, Mexico, and their diet and activity pattern. Both study groups preferred big trees for feeding and the group with lower availability of BTTFT in their home range fed from more, smaller food sources. Furthermore, both study groups also increased the number of food sources when their consumption of fruit decreased, and the group with lower availability of FrTFT in their home range fed from more food sources. The increase in the number of food sources used under such conditions, in turn, set up a process of higher foraging effort and lower rest. In summary, our results support other studies that suggest that the availability of big trees and fruit may be two important elements influencing the persistence of howler monkeys in forest fragments. Am. J. Primatol. 71:654–662, 2009. © 2009 Wiley‐Liss, Inc.
Social dynamics of the golden snub‐nosed monkey (Rhinopithecus roxellana): female transfer and one‐male unit succession
Authors: Qi Xiao‐Guang , Li Bao‐Guo , Garber Paul A. , Ji Weihong , Watanabe Kunio
Published: May 2009

Among primates that form multilevel societies, understanding factors and mechanisms associated with the movement of individuals between groups, clans, and one‐male social units offers important insight into primate reproductive and social strategies. In this research we present data based on an 8‐year field study of a multilevel troop of Sichuan snub‐nosed monkeys (Rhinopithecus roxellana) in the Qinling Mountains of China. Our study troop contained 78–126 individuals, and was usually organized into 6–8 one‐male units (OMU). The majority of OMUs were composed of networks of unrelated females and their offspring. We found that 59.7% (43/72) of subadult and adult females in our study troop transferred between OMUs (n=66) or disappeared (n=7) from the troop. In the majority of cases, two or more females transferred together into new OMUs or troops. InR. roxellana, new OMUs formed in several ways. During 2001–2008, 16 adult males appeared in the study troop. Over this period, we observed 13 different males who became harem leaders either by taking over an existing harem or by attracting females from other OMUs into their harem. We also observed four OMUs from a neighboring troop to successfully immigrate into the study troop. The number of individuals in these newly immigrated OMUs was significantly smaller than that number of individuals in resident OMUs. During harem formation, fighting between adult males was rarely observed, and female mate choice appeared to play a crucial role in harem male recruitment and replacement. These results suggest that golden snub‐nosed monkeys are organized in a nonmatrilineal social system. Female mate choice and possibly incest avoidance appear to play important roles in female transfer, male tenure, and OMU stability. Am. J. Primatol. 71:670–679, 2009. © 2009 Wiley‐Liss, Inc.
Why programs are no longer enough: An interview on collaborating at the U.S. TSA
Authors: Cohen Judith
Published: May 2009

How a federal agency, with tens of thousands of employees and the nation's security in its mission, remade its conflict resolution processes into a full‐fledged decisionmaking and management system. The U.S. Transportation Security Administration's Deborah A. Katz is interviewed by New York conflict resolution consultant Judith Cohen in the first of two parts.
The view from abroad on a parade of choices: Alternative processes to the ‘traditional’ alternative, arbitration
Authors: Rubino‐Sammartano Mauro
Published: May 2009

Mauro Rubino‐Sammartano, of Milan, Italy, discusses European alternatives to arbitration that have proven effective in resolving commercial disputes in a variety of forums.
The rest of the Sept. 11 cases–those that went to Court–are settled via mediation
Authors: Bleemer Russ
Published: May 2009

The federal judge overseeing the litigation brought by family members of Sept. 11 victims, as well as injured survivors, has closed the book on nearly all the cases. He cited mediation efforts by New York attorney Sheila L. Birnbaum that settled 72 of the 95 outstanding matters. Birnbaum discusses her special master assignment, and the emotionpacked mediation sessions.
Pharmacokinetics of intravenous immunoglobulin and outcome in Guillain‐Barré syndrome
Authors: Kuitwaard Krista , de Gelder Jenny , Tio‐Gillen Anne P. , Hop Wim C. J. , van Gelder Teun , van Toorenenbergen Albert W. , van Doorn Pieter A. , Jacobs Bart C.
Published: May 2009

Objective

Intravenous immunoglobulin (IVIg) is the first choice treatment for Guillain‐Barré syndrome (GBS). All patients initially receive the same arbitrary dose of 2g per kg body weight. Not all patients, however, show a good recovery after this standard dose. IVIg clearance may depend on disease severity and vary between individuals, implying that this dose is suboptimal for some patients. In this study, we determined whether the pharmacokinetics of IVIg is related to outcome in GBS.

Methods

We included 174 GBS patients who had previously participated in 2 randomized clinical trials. At entry, all patients were unable to walk unaided and received a standard dose of IVIg. Total IgG levels in serum samples obtained immediately before and 2 weeks after the start of IVIg administration were determined by turbidimetry and related to clinical outcome at 6 months.

Results

The increase in serum IgG (ΔIgG) 2 weeks after IVIg treatment varied considerably between patients (mean, 7.8g/L; standard deviation, 5.6g/L). Patients with a low ΔIgG recovered significantly more slowly, and fewer reached the ability to walk unaided at 6 months (log‐rank p < 0.001). In multivariate analysis adjusted for other known prognostic factors, a low ΔIgG was independently associated with poor outcome (p = 0.022).

Interpretation

After a standard dose of IVIg treatment, GBS patients show a large variation in pharmacokinetics, which is related to clinical outcome. This may indicate that patients with a small increase in serum IgG level may benefit from a higher dosage or second course of IVIg. Ann Neurol 2009;66:597–603
Recombinant C1 inhibitor in brain ischemic injury
Authors: Gesuete Raffaella , Storini Claudio , Fantin Alessandro , Stravalaci Matteo , Zanier Elisa R. , Orsini Franca , Vietsch Helene , Mannesse M. L. Maurice , Ziere Bertjan , Gobbi Marco , De Simoni Maria‐Grazia
Published: May 2009

Objective

C1 inhibitor (C1‐INH) is an endogenous inhibitor of complement and kinin systems. We have explored the efficacy and the therapeutic window of the recently available human recombinant (rh) C1‐INH on ischemic brain injury and investigated its mechanism of action in comparison with that of plasma‐derived (pd) C1‐INH.

Methods

rhC1‐INH was administered intravenously to C57Bl/6 mice undergoing transient or permanent ischemia, and its protective effects were evaluated by measuring infarct volume and neurodegeneration. The binding profiles of rhC1‐INH and pdC1‐INH were assessed in vitro using surface plasmon resonance. Their localization in the ischemic brain tissue was determined by immunohistochemistry and confocal analysis. The functional consequences of rhC1‐INH and pdC1‐INH administration on complement activation were analyzed by enzyme‐linked immunosorbent assay on plasma samples.

Results

rhC1‐INH markedly reduced cerebral damage when administered up to 18 hours after transient ischemia and up to 6 hours after permanent ischemia, thus showing a surprisingly wide therapeutic window. In vitro rhC1‐INH bound mannose‐binding lectin (MBL), a key protein in the lectin complement pathway, with high affinity, whereas pdC1‐INH, which has a different glycosylation pattern, did not. In the ischemic brain, rhC1‐INH was confined to cerebral vessels, where it colocalized with MBL, whereas pdC1‐INH diffused into the brain parenchyma. In addition, rhC1‐INH was more active than pdC1‐INH in inhibiting MBL‐induced complement activation.

Interpretation

rhC1‐INH showed a surprisingly wider time window of efficacy compared with the corresponding plasmatic protein. We propose that the superiority of rhC1‐INH is due to its selective binding to MBL, which emerged as a novel target for stroke treatment. Ann Neurol 2009;66:332–342
Pathogenic CD8+ T cells in multiple sclerosis
Authors: Friese Manuel A. , Fugger Lars
Published: May 2009

Traditionally, autoimmune pathogeneses have been attributed to CD4+ T lymphocytes, as in multiple sclerosis (MS), rheumatoid arthritis, type 1 diabetes mellitus, and/or to B lymphocytes, as in myasthenia gravis and systemic lupus erythematosus. That is because their primary genetic associations are mostly with certain human leukocyte antigen class II alleles, whose gene products present antigens to CD4+ T cells. Because few autoimmune diseases show stronger associations with major histocompatibility complex class I alleles (ankylosing spondylitis, Behçet's disease, and psoriasis), CD8+ T cells, which interact with major histocompatibility complex class I molecules, have been largely ignored in autoimmunity research. However, a variety of findings has recently revived interest in this population, particularly in MS. First, it shows associations with major histocompatibility complex class I alleles. Second, its lesions show a predominance of CD8+ T cells. Third, these represent effectors that can directly damage central nervous system target cells. Furthermore, several clinical trials of monoclonal antibodies specifically against CD4+ T cells, or the polarizing cytokines on which they depend, have failed to show any therapeutic benefit in MS, unlike broader‐spectrum antibodies that deplete all T cells. Here, we review the evidence that CD8+ T cells play a role in MS pathogenesis. Ann Neurol 2009;66:132–141
Human neural stem cells ameliorate autoimmune encephalomyelitis in non‐human primates
Authors: Pluchino Stefano , Gritti Angela , Blezer Erwin , Amadio Stefano , Brambilla Elena , Borsellino Giovanna , Cossetti Chiara , Del Carro Ubaldo , Comi Giancarlo , 't Hart Bert , Vescovi Angelo , Martino Gianvito
Published: May 2009

Objective

Transplanted neural stem/precursor cells (NPCs) display peculiar therapeutic plasticity in vivo. Although the replacement of cells was first expected as the prime therapeutic mechanism of stem cells in regenerative medicine, it is now clear that transplanted NPCs simultaneously instruct several therapeutic mechanisms, among which replacement of cells might not necessarily prevail. A comprehensive understanding of the mechanism(s) by which NPCs exert their therapeutic plasticity is lacking. This study was designed as a preclinical approach to test the feasibility of human NPC transplantation in an outbreed nonhuman primate experimental autoimmune encephalomyelitis (EAE) model approximating the clinical and complex neuropathological situation of human multiple sclerosis (MS) more closely than EAE in the standard laboratory rodent.

Methods

We examined the safety and efficacy of the intravenous (IV) and intrathecal (IT) administration of human NPCs in common marmosets affected by human myelin oligodendrocyte glycoprotein 1‐125–induced EAE. Treatment commenced upon the occurrence of detectable brain lesions on a 4.7T spectrometer.

Results

EAE marmosets injected IV or IT with NPCs accumulated lower disability and displayed increased survival, as compared with sham‐treated controls. Transplanted NPCs persisted within the host central nervous system (CNS), but were also found in draining lymph nodes, for up to 3 months after transplantation and exhibited remarkable immune regulatory capacity in vitro.

Interpretation

Herein, we provide the first evidence that human CNS stem cells ameliorate EAE in nonhuman primates without overt side effects. Immune regulation (rather than neural differentiation) is suggested as the major putative mechanism by which NPCs ameliorate EAE in vivo. Our findings represent a critical step toward the clinical use of human NPCs in MS. Ann Neurol 2009;66:343–354
Discovery of Heteroatom‐“Embedded” Te⊂{W18O54} Nanofunctional Polyoxometalates by Use of Cryospray Mass Spectrometry
Authors: Yan Jun , Long De‐Liang , Wilson Elizabeth F. , Cronin Leroy
Published: May 2009

Das Cryo‐Spiel: Die hier beschriebenen nanofunktionellen Cluster mit eingebettetem Heteroatom enthalten eine [TeVIO6]6−‐Spezies in einem {W18O54}‐Käfig. Die tellurhaltige Spezies aktiviert nicht nur die {W18O54}‐Clusteroberfläche für die Bildung größerer nanoskaliger Strukturen wie [H10TeVI2W58O198]26−, sondern sie geht auch im Innern des Clusters eine Redoxreaktion von [TeVIO6]6− zu [TeIVO3]2− ein.

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First X‐Ray Structure Analyses of Rhodium(III) η1‐Allyl Complexes and a Mechanism for Allylic Isomerization Reactions
Authors: Wucher Barbara , Moser Michael , Schumacher Stephanie A. , Rominger Frank , Kunz Doris
Published: May 2009

Metal‐to‐metal allyl transfer: Using the first structurally characterized rhodium η1‐allyl complexes it is shown that the σ‐bound allyl substituent can be transferred from the RhIII complex to a RhI complex in a fast equilibrium. This process may account for the decrease in regioselectivity observed in allylic alkylation reactions in which complex 1 is used as a catalyst.

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Cycle‐Specific Organocascade Catalysis: Application to Olefin Hydroamination, Hydro‐oxidation, and Amino‐oxidation, and to Natural Product Synthesis
Authors: Simmons Bryon , Walji Abbas M. , MacMillan David W. C.
Published: May 2009

United in effort: The combined application of iminium (Im) and enamine (En) catalysts can effect a range of valuable asymmetric transformations including 1,2‐hydroamination, ‐hydro‐oxidation, and ‐amino‐oxidation of olefins (see picture). An enantioselective organocascade catalysis was also applied in the synthesis of a complex natural product.

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Zinc‐Mediated Formation of Trifluoromethyl Ethers from Alcohols and Hypervalent Iodine Trifluoromethylation Reagents
Authors: Koller Raffael , Stanek Kyrill , Stolz Daniel , Aardoom Raphael , Niedermann Katrin , Togni Antonio
Published: May 2009

A (fluor)ry of activity: The transfer of an intact trifluoromethyl group from a hypervalent iodine reagent to an aliphatic alcohol occurs smoothly upon activation by zinc bis(triflimide). This constitutes a straightforward method for the preparation of trifluoromethoxy alkyl derivatives, compounds otherwise difficult to access.

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Stereodivergent Synthesis of 17‐α and 17‐β‐Aryl Steroids: Application and Biological Evaluation of D‐Ring Cortistatin Analogues
Authors: Shi Jun , Shigehisa Hiroki , Guerrero Carlos A. , Shenvi Ryan A. , Li Chuang‐Chuang , Baran Phil S.
Published: May 2009

One stereocenter makes all the difference: The synthesis and biological evaluation of 17‐epi‐cortistatin A is reported from a common intermediate used to procure natural cortistatin A. The synthesis features a unique stereocontrolled Raney‐Ni reduction process that can be employed to reliably produce both α‐ and β‐configured D‐ring aryl steroids. Biological evaluations of these “cortalogs” are reported for the first time.

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Comparisons of age, growth, and maturity between male and female, and diploid and triploid individuals in Carassius auratus from Okinawa‐jima Island, Japan
Authors: Takada Mikumi , Tachihara Katsunori
Published: May 2009

Carassius auratus, a primary freshwater fish with bisexual diploid and unisexual gynogenetic triploid lineages, is distributed widely in and around the Eurasian continent and is especially common in East Asia. East Asian C. auratus diverged genetically to form local endemic populations in different regions, and those distributed in the Ryukyu Archipelago form a local endemic population that can be regarded as an evolutionarily significant unit because of its high phylogenetic independence and evolutionary distinctiveness. Although the evolutionary uniqueness of this population should be conserved, its distribution area and population size are decreasing rapidly, and some island populations are currently considered endangered or already extinct.

To develop effective conservation measures to stop the current decline of Ryukyuan C. auratus, ecological data need to be collected. In this study, life history data for a C. auratus population distributed in the Hiji River system were collected by estimating age, growth, and spawning season.

The spawning season of C. auratus in the Hiji River extended from March to September, peaking during March–May. Females became sexually mature in their second year, but males reached maturity and were able to spawn as early as in the late spawning season of their year of hatching. Once having reached sexual maturity, males probably continuously stay ripe throughout their life.

Sagittal otoliths of C. auratus proved to be useful ageing structures because one annual increment is formed on the sagittal otolith before the spawning season in each year. The oldest fish observed were a 10‐year‐old female and an 11‐year‐old male. Females showed faster somatic growth and higher final standard length than males, and a sexual size dimorphism was observed.

The standard length at each age class did not differ between diploid and triploid C. auratus, suggesting that triploid growth rates were almost equal to those of diploids. Copyright © 2009 John Wiley & Sons, Ltd.
UV/Vis to NIR Photoconduction in Cyclopalladated Complexes
Authors: Godbert Nicolas , Dattilo Davide , Termine Roberto , Aiello Iolinda , Bellusci Anna , Crispini Alessandra , Golemme Attilio , Ghedini Mauro
Published: May 2009

Funky discotics: Photoconductivity is measured in newly synthesized cyclopalladated metallomesogens exhibiting hexagonal columnar mesophases at room temperature. The tuning of the HOMO/LUMO energy levels by modification of the chain/core linkage (ester 1 vs ether 2) makes compound 2 photoconductive across the whole UV/Vis/NIR range.

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The incorporation of a rigid core, formed by a cyclopalladated azobenzene fragment bonded to an ancillary Schiff base ligand, into molecules with 12 or 11 peripheral alkyl chains has been successfully achieved. These new complexes, 1 and 2, respectively, are columnar liquid crystals between room temperature and about 50 °C. Both cyclometallated and ancillary ligands have been polyalkylated through either aryl ester (electron‐withdrawing group) or aryl ether (electron‐releasing group) linkages, in order to tune the HOMO/LUMO energy levels. The photoconductive properties of 1 and 2 have been studied as a function of their absorption properties before and after annealing, from the UV/Vis to NIR region. Compared with the reference compounds, tris‐alkynyl benzene discotics, these new materials gave similar performances (σ/I∼8×10−13 S cm W−1 with E=10 V μm−1 at λ=370 nm). Moreover, complex 2 shows a normalized photoconductivity σ/I=8.5×10−13 S cm W−1 at λ=760 nm. Organic photoconductors in such a high wavelength spectral range are not common and are usually assembled by mixing dyes with organic semiconductors.
Effect of Structural Modification on the Quantum‐Size Effect in II–VI Semiconducting Nanocrystals
Authors: Viswanatha Ranjani , Sarma D. D.
Published: May 2009

Formation also matters: A model to understand the variation in the bandgap with size for nanoclusters is presented. This model shows that the confinement effect and consequent bandgap variation depend not only on shape and size, but also on the structure of the nanocrystal.

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The electronic structure of group II–VI semiconductors in the stable wurtzite form is analyzed using state‐of‐the‐art ab initio approaches to extract a simple and chemically transparent tight‐binding model. This model can be used to understand the variation in the bandgap with size, for nanoclusters of these compounds. Results complement similar information already available for same systems in the zinc blende structure. A comparison with all available experimental data on quantum size effects in group II–VI semiconductor nanoclusters establishes a remarkable agreement between theory and experiment in both structure types, thereby verifying the predictive ability of our approach. The significant dependence of the quantum size effect on the structure type suggests that the experimental bandgap change at a given size compared to the bulk bandgap, may be used to indicate the structural form of the nanoclusters, particularly in the small size limit, where broadening of diffraction features often make it difficult to unambiguously determine the structure.
Structural and Nonlinear Optical Properties of Aligned Heterotrinuclear [RuII‐(Spacer)‐MII‐(Spacer)‐RuII] Complexes (M=Pd, Pt; spacer=4‐ethynylpyridine)
Authors: Ge Qingchun , Dalton Gulliver T. , Humphrey Mark G. , Samoc Marek , Hor T. S. Andy
Published: May 2009

Optical alloy: “Linear” heterotrinuclear assemblies, with the metals separated by 4‐ethynylpyridine spacers [RuCp(CCpy‐4)(dppf)]2[MCl2] (M=Pd, Pt), have been structurally identified. They are electrochemically active and show good cubic nonlinear optical responses.

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Lewis addition between the metalloligand [RuCp(CCpy‐4)(dppf)] (1) (dppf=(C5H4PPh2)2Fe) and MCl2(CH3CN)2 gives [RuCp(CCpy‐4)(dppf)]2[MCl2] (M=Pd (2) and Pt (3)), all of which have been spectroscopically and crystallographically characterized. The mixed‐metal adducts show the d6‐d8‐d6 metal alignment maintained by the trans disposition of the directionally rigid 4‐ethynylpyridine at the centrosymmetric square‐planar metal center. Electrochemical studies of these and the related known complexes trans‐[RuCl(CCpy‐4)(dppm)2] (4) and [trans‐RuCl(CCpy‐4)(dppm)2]2[MCl2] (dppm=Ph2PCH2PPh2) (M=Pd (5) and Pt (6)) suggest that the spacer‐linked heterotrinuclear network is able to stabilize the oxidized RuIII better than the metalloligand precursor. Cubic nonlinear optical responses are also generally higher for the heterometallic complexes. The γreal value of the PdRu2 dppm complex 5 is among the largest for linear organometallic complexes.
Ultra scale‐down prediction using microwell technology of the industrial scale clarification characteristics by centrifugation of mammalian cell broths
Authors: Tait A.S. , Aucamp J.P. , Bugeon A. , Hoare M.
Published: May 2009

This article describes how a combination of an ultra scale‐down (USD) shear device feeding a microwell centrifugation plate may be used to provide a prediction of how mammalian cell broth will clarify at scale. In particular a method is described that is inherently adaptable to a robotic platform and may be used to predict how the flow rate and capacity (equivalent settling area) of a centrifuge and the choice of feed zone configuration may affect the solids carry over in the supernatant. This is an important consideration as the extent of solids carry over will determine the required size and lifetime of a subsequent filtration stage or the passage of fine particulates and colloidal material affecting the performance and lifetime of chromatography stages. The extent of solids removal observed in individual wells of a microwell plate during centrifugation is shown to correlate with the vertical and horizontal location of the well on the plate. Geometric adjustments to the evaluation of the equivalent settling area of individual wells (ΣM) results in an improved prediction of solids removal as a function of centrifuge capacity. The USD centrifuge settling characteristics need to be as for a range of equivalent flow rates as may be experienced at an industrial scale for a machine of different shear characteristics in the entry feed zone. This was shown to be achievable with two microwell‐plate based measurements and the use of varying fill volumes in the microwells to allow the rapid study of a fivefold range of equivalent flow rates (i.e., at full scale for a particular industrial centrifuge) and the effect of a range of feed configurations. The microwell based USD method was used to examine the recovery of CHO‐S cells, prepared in a 5 L reactor, at different points of growth and for different levels of exposure to shear post reactor. The combination of particle size distribution measurements of the cells before and after shear and the effect of shear on the solids remaining after centrifugation rate provide insight into the state of the cells throughout the fermentation and the ease with which they and accumulated debris may be removed by continuous centrifugation. Hence bioprocess data are more readily available to help better integrate cell culture and cell removal stages and resolve key bioprocess design issues such as choice of time of harvesting and the impact on product yield and contaminant carry over. Operation at microwell scale allows data acquisition and bioprocess understanding over a wide range of operating conditions that might not normally be achieved during bioprocess development. Biotechnol. Bioeng. 2009; 104: 321–331 © 2009 Wiley Periodicals, Inc.
Cyclo-oxygenase 2 inhibitors and the risk of anastomotic leakage after fast-track colonic surgery
Authors: Holte K , Andersen J , Jakobsen D Hjort , Kehlet H
Published: May 2009

Background

Anastomotic leakage occurs after 3–6 per cent of colonic resections. The influence of analgesic agents is largely unknown. This study determined the rate of anastomotic leakage in a series of patients who had colonic surgery over a 9-year period with or without use of a cyclo-oxygenase inhibitor for postoperative analgesia.

Methods

Patients with anastomotic leakage following a standard fast-track procotol between April 1997 and May 2006 were identified from a prospective, consecutive database. During this period there were two changes in perioperative management: cessation of preoperative oral bowel preparation in August 2002 and the use of celecoxib for postoperative analgesia between May 2003 and November 2004. Rates of anastomotic leakage during the various periods were determined and compared.

Results

Some 28 (5·6 per cent) of 502 patients had an anastomotic leak. The incidence of leakage increased significantly during the period of celecoxib use (15·1 per cent), versus 3·3 and 1·5 per cent respectively before and after celecoxib use (P < 0·001). Leakage rates were similar with or without oral bowel preparation (3·5 versus 1·7 per cent respectively; P = 0·346) when celecoxib was not used.

Conclusion

A detrimental effect of celecoxib on anastomotic healing is suggested, and requires further evaluation.
Patency of splenic vessels after laparoscopic spleen and splenic vessel-preserving distal pancreatectomy
Authors: Yoon Y-S , Lee K H , Han H-S , Cho J Y , Ahn K S
Published: May 2009

Background

This study evaluated the short- and long-term patency of preserved splenic vessels after laparoscopic spleen-preserving distal pancreatectomy (SPDP) with preservation of the splenic vessels.

Methods

This single-centre retrospective study included all patients who had undergone splenic vessel-preserving laparoscopic SPDP between 2004 and 2007. The patency of the splenic vessels was assessed by abdominal computed tomography and classified into three grades according to the degree of stenosis.

Results

Twenty-two patients were included. The preoperative patency of the splenic artery and vein was normal in 20 and 19 patients respectively. Normal patency of the splenic artery and vein was observed in 16 and five patients respectively within 1 month of surgery, and in 19 and nine patients 6 months or more after operation. Nine of ten patients with complete splenic vein occlusion developed a collateral circulation in the late postoperative phase. Splenic perfusion was well preserved in all patients.

Conclusion

Splenic vessel-preserving laparoscopic SPDP has the short-term benefit of good perfusion to the spleen. In the long term, there is a risk of left-sided portal hypertension if the splenic vein becomes occluded after surgery.
The latent presentation of pancreatic fistulas
Authors: Pratt W B , Callery M P , Vollmer C M
Published: May 2009

Background

Pancreatic fistula is traditionally suspected on the basis of increased drain amylase activity. However, some patients have a low amylase level but later manifest clinical evidence of a fistula. This study investigated the prevalence and significance of these presentations.

Methods

Severity of fistula was determined according to the International Study Group on Pancreatic Fistula criteria for 405 consecutive pancreatic resections. Latent fistulas, initially lacking amylase-rich effluent but ultimately clinically relevant (grades B or C), were examined to determine their impact and significance.

Results

Fistula of any extent occurred in 107 patients (26·4 per cent). Latent fistulas occurred in 20 patients (4·9 per cent of all resections, 18·7 per cent of all fistulas and 36 per cent of all clinically relevant fistulas). Initial amylase activity was consistently low (range 3–235 units/l), but these fistulas subsequently manifested clinical relevance (abdominal pain, radiographic evidence, fever, sinister effluent, wound infection). Latent presentations had twice the infection rate of evident fistulas, required more aggressive interventions, resulted in longer hospitalizations and incurred greater hospital costs.

Conclusion

A considerable proportion of patients with pancreatic fistula do not initially demonstrate an amylase-rich effluent. These patients have significantly worse outcomes. In fistula definition, the clinical course is important as well as biochemical parameters.
Possible association between genetic polymorphisms in transforming growth factor β receptors, serum transforming growth factor β1 concentration and abdominal aortic aneurysm
Authors: Golledge J , Clancy P , Jones G T , Cooper M , Palmer L J , van Rij A M , Norman P E
Published: May 2009

Background

Previous studies have suggested a role for transforming growth factor (TGF) β and its receptor in thoracic aortic aneurysm, but their role in abdominal aortic aneurysm (AAA) is unknown. This study examined the possible association between TGF-β receptor 1 and 2 (TGFBR-1 and -2) single nucleotide polymorphisms (SNPs) and serum TGF-β1 with AAA.

Methods

Serum concentrations of TGF-β1 and 58 SNPs for TGFBR-1 and -2 were examined in 1003 and 1711 men respectively from the Health In Men Study. Validation of SNPs was examined in a second referral cohort of 1043 subjects from New Zealand, of whom 654 had an AAA.

Results

Serum TGF-β1 was not associated with AAA. Only one SNP in TGFBR-2 was weakly associated with AAA; TGFBR2 g.42917C > T, SNP ID rs1078985CC; odds ratio 0·64 (95 per cent confidence interval (c.i.) 0·45 to 0·93); P = 0·020 uncorrected; but this association did not hold after adjusting for multiple testing and was not validated in the New Zealand cohort: odds ratio 0·98 (95 per cent c.i. 0·50 to 1·94); P = 0·960.

Conclusion

These findings suggest there is no important role of genetic polymorphisms in the main receptors for TGF-β and circulating TGF-β1 in AAA in older individuals.
A remote laboratory experiment for 4‐quadrant control of a DC motor
Authors: Irmak Erdal , Bayindir Ramazan , Colak Ilhami , Soysal Mustafa
Published: May 2009

This study presents development of the system architecture to perform laboratory experiments over the Internet for electrical engineering education. Design and implementation of four‐quadrant speed control experiment for a direct current (DC) motor is given in the article as a sample remote experimental study. The system designed consists of four main parts as a client, a server, a data acquisition unit and an experimental set with a control unit. MATLAB web server (MWS) is used to send and receive data or graphics over the Internet. While the experiment is being operated, the real experimental set placed in the laboratory can be monitored by the remote user. Evaluation results show that the system designed accelerates the learning period, increases the concentration on the experiment and provides a safe environment for four‐quadrant speed control experiment of a DC motor. © 2009 Wiley Periodicals, Inc. Comput Appl Eng Educ 19: 747–758, 2011
Magnetic field generated by sagging conductors of overhead power lines
Authors: Riba Ruiz Jordi‐Roger , Garcia Espinosa Antonio
Published: May 2009

This article describes the implementation of the equations that govern the behavior of magnetic fields generated by three‐phase power lines. From the equations obtained in this work, the profiles of the magnetic fields generated by different practical power lines configurations have been analyzed. Results from simulations have been contrasted with experimental data showing a close agreement between them. These values have been also compared with current international regulations showing that in all the situations their values fulfill the reference levels. Additionally, the effect of a conducting ground has been discussed. It has been proved that in practical cases the effects from the earth currents can be neglected as compared with effects from line currents. Furthermore special attention is paid to the catenary shape of overhead conductors. The magnetic field generated by sagging conductors has been calculated and compared with the one generated by straight equivalent conductors. © 2009 Wiley Periodicals, Inc. Comput Appl Eng Educ 19: 787–794, 2011
Training the workforce following a serious case review: lessons learnt from a death by fabricated and induced illness
Authors: Horwath Jan , Tidbury Wade
Published: May 2009

In England, when a child dies as a result of suspected maltreatment, the Local Safeguarding Children Board is required to establish whether lessons can be learnt about collaborative working to safeguard children. These reviews usually include recommendations for both inter and intra‐agency training. In this paper, the authors argue that it is crucial, when planning and delivering training in this situation, to recognise the emotional impact on the workforce of the death of a child from maltreatment. This is particularly important when the child has died as a result of fabricated and induced illness (FII) by a carer and professionals may have inadvertently contributed to the child's suffering. Drawing on a case example of training following the death of a child from FII, this paper considers the challenges encountered by those responsible for commissioning and providing training. Attention is given to managing logistics, such as time delays between the death of the child and the eventual publication of the serious case review. The particular knowledge and skills required by trainers, not only in relation to the subject matter but also in managing complex group processes, are discussed. The support required by course participants and the trainers themselves is explored. The paper concludes with a checklist for those commissioning and providing training. Copyright © 2009 John Wiley & Sons, Ltd.
Parenting groups for parents whose children are in care
Authors: Salveron Mary , Lewig Kerry , Arney Fiona
Published: May 2009

Excluding very severe child abuse cases, biological parents are usually encouraged to maintain contact with their children in care. Parent‐child contact is often considered important because it can maintain the child's psychological identity and well‐being. It can also maintain parent‐child attachment and in some cases facilitate reunification. Improving parenting skills is viewed as an important method by which contact between children and their biological parents can be enhanced. However, mainstream parenting groups are often unsuitable for parents whose children are in care for a number of reasons. There is stigma involved with having children in care, such parents have very complex lives and there are reduced opportunities to practise skills learnt with their children. Groups designed specifically for parents whose children are in care appear to be a promising approach to improving the quality of contact between these parents and their children. This paper will review group‐based approaches to working with biological parents whose pre‐school‐aged children have been placed in care. The paper will also report the findings of a research project designed to identify key facilitators and barriers to parental involvement in a group‐based programme which includes contact between parents and their children who have been placed in care. Copyright © 2009 John Wiley & Sons, Ltd.
The role of social categorization and identity threat in the perception of migrants
Authors: van Rijswijk Wendy , Hopkins Nick , Johnston Hannah
Published: May 2009

This paper investigates how the categorization of migrant workers shapes their reception. In an experiment with Northern Irish Protestants we manipulated the representation of Poland to make the Catholicism of Polish migrants either more, or less, salient. Furthermore, judgements of Polish migrants were obtained under conditions designed to encourage participants to believe that sectarian conflict in Northern Ireland was either resolved, or still a strong feature of the present social landscape. Overall, results showed that when Poland's Catholicism was salient, participants were less welcoming of Polish migrants. Furthermore, this effect was mediated by increases in the level of symbolic threat participants believed the migrants posed to participants' (Protestant) community identity. Copyright © 2009 John Wiley & Sons, Ltd.
Synthesis and in vitro Activity of Heterocyclic Inhibitors of CYP2A6 and CYP2A13, Two Cytochrome P450 Enzymes Present in the Respiratory Tract
Authors: Chougnet Antoinette , Woggon Wolf‐D. , Locher Esther , Schilling Boris
Published: May 2009

To be sniffed at: Several 1‐ and 2‐substituted 1H‐imidazoles and 2‐substituted oxazoles, oxazolines and pyrazines have been synthesized and tested as inhibitors of the cytochrome P450 enzymes CYP2A6 and CYP2A13. 1‐Substituted 1H‐imidazoles bearing short chains (pentyl, hexyl or hexenyl) were found to be potent inhibitors of both enzymes, and showed IC50values of about 2 μM.

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The synthesis of several heterocyclic compounds (1‐ or 2‐substituted1H‐imidazoles and 2‐substituted oxazoles, oxazolines and pyrazines) has been achieved. These compounds were tested as inhibitors of CYP2A6 and CYP2A13—two cytochrome P450 enzymes present in the respiratory tract—with a view to preventing the formation of carcinogenic metabolites of nicotine and inhibiting the metabolism of fragrances. 1‐Substituted imidazoles bearing short alkyl chains displayed IC50values of around 2 μMfor both enzymes, together with high vapour pressures.
Proteolysis of Peptide Dendrimers
Authors: Sommer Peter , Fluxa Viviana S. , Darbre Tamis , Reymond Jean‐Louis
Published: May 2009

Happy tree‐like friends. Using trypsin and α‐chymotrypsin cleavage sites as models, we show that the protease reactivity of peptide dendrimers, such as the structure illustrated in the figure, can be controlled by the degree of branching. Such a control provides a novel possibility to tune the biological properties of peptide dendrimers, and should be generally useful for their employment as functional biomolecule analogues, for example, in drug delivery applications.

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The ability of proteins and peptides to undergo proteolysis is essential to their biological function. Herein, we report the first detailed study of the protease reactivity of peptide dendrimers. Dendrimers are regularly ramified, tree‐like synthetic macromolecules with promising application in technology and medicine. Using trypsin and α‐chymotrypsin cleavage sites as models, we show that the protease reactivity of peptide dendrimers can be controlled by the degree of branching. Dendrimers with two or three amino acids between branching points were readily cleaved by trypsin irrespective of the position of the reactive sequence within the dendrimers, for example in D1, (Ac‐Gly‐Phe‐Pro)4(Dap‐Hyp‐Arg↓Met)2Dap‐Ser‐Gly‐βAla‐NH2, and D12, (Ac‐Ser‐Ala)8(Dap‐Ala‐Arg↓)4(Dap‐Ala‐Asp)2Dap‐Phe‐Ala‐Lys*‐NH2 (Dap: (S)‐2,3‐diaminopropionic acid branching point, Hyp: hydroxyproline, Lys*: FITC‐labeled lysine, ↓: cleavage site). On the other hand cleavage was blocked in more compact dendrimers with only one amino acid between branching points, for example in D18B, (Ac‐Glu)8(Dap‐Phe)4(Dap‐Arg)2Dap‐Leu‐NH2). The control of proteolysis by topology provides a novel possibility to tune the biological properties of peptide dendrimers not available in linear peptides, and should be generally useful for their use as functional biomolecule analogues, for example, in the context of drug delivery applications.
Deviations from linearity in statistical evaluation of linearity in assay validation
Authors: Liu Jen‐pei , Chow Shein‐Chung , Hsieh Tsung‐Cheng
Published: May 2009

Linearity and linear range are the key evaluations of the accuracy in assay validation. The average deviation from linearity (ADL) and the sum of squares of deviations from linearity (SSDL) have been proposed for assessment of the linearity. However, both ADL and SSDL do no consider the variability of the assay for evaluation of linearity. Therefore, we proposed the coefficient of variation of deviations from linearity (CVDL) as an alternative measure for the linearity assessment. For the inference of evaluation of linearity, we proposed testing procedures based on generalized pivotal quantities (GPQ) of ADL and CVDL for evaluation of linearity. The simulation studies were conducted to empirically investigate the size and power between the three methods. The simulation results show that all three methods adequately control size. However, the ADL method is uniformly more powerful than the other two methods. A numeric example illustrates the proposed methods. Copyright © 2009 John Wiley & Sons, Ltd.
Analytical characterization of RF phase‐cycled balanced steady‐state free precession
Authors: Lauzon M. Louis , Frayne Richard
Published: May 2009

Balanced steady‐state free precession (bSSFP) techniques, commonly called True‐FISP, FIESTA, or balanced FFE, are rapid, efficient, high signal‐to‐noise ratio sequences used in angiographic, cardiac and abdominal MR imaging. One of their major drawbacks is their sensitivity to off‐resonance effects arising from Bo inhomogeneities, which can produce the familiar dark bands in the images. Radio frequency (RF) phase cycling is known to minimize this artifact. Although RF phase‐cycled bSSFP is an accepted and firmly established technique, a simple and intuitive analytical signal equation has not yet been provided. Here, a complete theoretical framework is developed from which insightful characterizations such as signal uniformity, optimal flip angle, SNR efficiency, and banding effect minimization are provided. The analytical predictions and guidelines are substantiated via direct numerical simulations for clinically relevant tissues (e.g., water‐like organs and lipids) using various acquisition conditions, and also verified experimentally with phantoms. We demonstrate that the banding artifact can be virtually eliminated, even for phantoms immersed in significantly nonuniform magnetic fields. © 2009 Wiley Periodicals, Inc. Concepts Magn Reson Part A 34A: 133–143, 2009.
Undesired gradients in low‐field magnetic resonance imaging
Authors: Ullah Rafi , Anwar Muhammad Sabieh
Published: May 2009

Magnetic resonance imaging (MRI) is a beautiful application of the phenomenon of nuclear magnetic resonance (NMR). Classically, the field strength is regarded as one measure of its quality because high field strength gives higher signal to noise ratios, better resolution and reduced scan times. So high field MRI has historically drawn a lot of attention. However, high‐field MRI has some disadvantages like reduced relaxation times and high susceptibility gradients. Furthermore, high‐field MRI systems are bulky, immovable, and very expensive. These reasons have motivated interest in the subject of low field MRI. The downside is that in the low field regime, we encounter the problem of undesired gradients appearing along with the desired ones. The presence of these additional gradients, generally known as concomitant gradients, directly follows from the fundamental Maxwell equations. The undesired gradients cause strong image distortions. In this article we discuss undesired gradients and work out their quantitative contribution towards the resulting image distortion. The gradient field is expressed in terms of a consistent tensorial description, including terms to arbitrary order. It is explored that the exact form of the undesired gradients can have an impact even in certain high‐field MRI cases. Finally, we also appreciate the effects of these gradients in other physical systems such as the Stern‐Gerlach experiment and the steering of magnetic species in solution. © 2009 Wiley Periodicals, Inc. Concepts Magn Reson Part A 34A: 173–190, 2009.