bluuebunny/crossref_metadata_2025 huggingface dataset:
Alkaloids of Papaver argemone L. and Papaver pavoninum FISCH. et MEY. From the Argemonorhoeades FEDDE section
Authors: Táborská Eva , Dostál Jiří , Bochořáková Hana , Věžník František
Published: June 2010

Papaver argemone L. and Papaver pavoninum FISCH. et MEY. species of the Argemonorhoeades FEDDE (Papaveraceae) section were studied. A very low content of alkaloids was found in both species (less than 0·05%). P. argemone contains corytuberine and its quaternary N-methyl derivative magnoflorine as the dominant bases. As minor constituents were isolated: protopine, isocorydine, scoulerine, and alkaloids PAR 1, PAR 2, PAR 3. Chromatographic analysis detected allocryptopine, cryptopine, coptisine and traces of rhoeadine, papaverrubines C, D and E, and more than 6 unidentified bases. P. pavoninum gave N2-methyl-1,2,3,4-tetrahydro-β-carboline as the dominant alkaloid, along with minor amounts of the tertiary bases protopine, allocryptopine, corydine, isocorydine and corytuberine. Of quaternary bases, coptisine, magnoflorine and an unidentified alkaloid PP 1 were isolated. The presence of many other, considerably labile bases has been proven in both species.
The application of inner projection technique to many electron systems as compared with the coupled cluster expansion. A study of the Pariser-Parr-Pople model of the benzene molecule
Authors: Čížek Jiří , Vinette Francine
Published: June 2010

The technique of inner projection is used for the first time in a chemical context, namely for the study of the ground state energy of the Pariser-Parr-Pople model of the benzene molecule. The lower bound for the energy is calculated for three types of parametrization. These results are compared with the “exact” energies which are obtained from full configuration interaction. It is shown that the inner projection technique provides very good lower bounds for the energy. In addition, we compare these inner projection results with those obtained by other approximative techniques, namely with the results of the Coupled Pair Many Electron Theory. A discussion of the application of the method of intermediate hamiltonians and the inner projection technique is also included.
Dynamics of the ion-molecule reaction D2O+ (NH3, NH2) HD2O+ from crossed-beam scattering experiments
Authors: Vančura Jan , Herman Zdeněk
Published: June 2010

Dynamics of the HD2O+ formation in the reaction of D2O+ and NH3 was investigated in a crossed-beam scattering experiment. At T = 1·5 eV (c.m.) the product is formed simultaneously by two different collision mechanisms, by a direct H-atom transfer and by the decomposition of an intermediate complex (D2O.NH3)+; the probabilities of the two mechanisms are about equal at this collision energy. The scattering makes it possible to suggest that in the critical configuration the intermediate complex is a prolate, near-linear species D2OH+.NH2.
(1S,7S)-7-Methyl-6,9-diazatricyclo[6,3,0,01,6]tridecane-5,10-dione, a tricyclic spirodilactam containing non-planar amide groups: Synthesis, NMR, crystal structure, absolute configuration, electronic and vibrational circular dichroism
Authors: Maloň Petr , Barness C. L. , Buděšínský Miloš , Dukor Rina K. , Van der Helm Dick , Keiderling Timothy A. , Koblicová Zdena , Pavlíková Františka , Tichý Miloš , Bláha Karel
Published: June 2010

The title spirocyclic dilactam (1S,7S)-7-methyl-6,9-diazatricyclo[6,3,0,01,6]tridecan-5,10-dione (I), a molecule designed to contain non-planar amide groups, has been synthesized from an optically active precursor of known absolute configuration. The relative and absolute configuration have been determined by X-ray diffraction. The conformation of the compound has been investigated by X-ray, 1H and 13C NMR, electronic and vibrational circular dichroism. The compound possesses moderately non-planar amide groups in the two rings of nonequal geometry. The electronic CD is dominated by inherent chirality of the amide chromophores. The dilactams I and II ((1S,6S)-6-methyl-5,8-diazatricyclo[6,3,0,01,5]undecan-4,9-dione – having five-membered rings) exhibit monosignate amide I VCD and strong VCD bands in the mid-ir region.
Absolute configuration of gossypol
Authors: Huang Liang , Si Yi-Kang , Snatzke Günther , Zheng Duo-Kai , Zhou Jin
Published: June 2010

The absolute configuration of the physiologically active (-)-gossypol has been suggested to be M by application of the coupled oscillator theory to its CD.
Revision of nido-2,6-C2B7H11 to the arachno-4,5-C2B7H13 structure. Determination of the structure from NMR spectra and chemical origin
Authors: Heřmánek Stanislav , Jelínek Tomáš , Plešek Jaromír , Štíbr Bohumil , Fusek Jiří
Published: June 2010

The assymetric C2B7 carborane held until the present for 2,6-C2B7H11, is in reality the arachno-4,5-C2B7H13 carborane (I) with two adjacent B-H-B bridges, one BH2, one CH2 and one CH group in the hexagonal open-face. The arrangement of the boron network was determined on the basis of the 11B, 11B-11B COSY, 1H and 13C NMR spectra and on the T1(B) study. The connection of B- with C-skeletal atoms was deduced from the positions of deuterium in the deutero analogs prepared by the CH2O/D3O+ degradation of three selectively deuterated nido-[7,8-C2B9H12]- anions. A selective transmission of D from CD2O to the B(9) vertex in the course of the CD2O/D3O+ degradation was observed. The structure of arachno-4,5-C2B7H13 is consistent with the different pathways of its preparation.
Conformation of branched polypeptides: The influence of relative position of leucine residues in the side chains
Authors: Mező Gabor , Votavová Hana , Hudecz Ferencz , Kajtár Judit , Šponar Jaroslav , Szekerke Mária
Published: June 2010

Branched polypeptides were synthesized with the general formula poly(Lys-(Xi)) or poly(Lys-(DL-Alam-Xi)), where X = Leu or D-Leu, i < 1, 1 < m < 2. Coupling of Leu or D-Leu to poly(Lys) was achieved by the active ester method. The short DL-Ala oligomers were joined to the side chains by polymerisation of N-carboxy-DL-Ala anhydride. The CD measurements performed in water solutions of various pH and ionic strength indicated that joining Leu or D-Leu directly to Lys ε-amino groups increases dramatically the helix forming tendency. However, this ability was somewhat less pronounced with the D-enantiomer of Leu in accordance with our previous observations concerning the role of configuration. The polypeptide with short DL-Ala oligomers as outside determinants was investigated extensively even in trifluoroethanol-water mixtures and SDS solutions. No significant conformational influence could be demonstrated by the elongation of the branches with 1-2 DL-Ala residues.
A study to the isolation of iridium from platinum metal mixtures
Authors: Kálalová Eliška , Kolářová Marcela , Thuy Pham
Published: June 2010

Sorption from solution onto a glycidyl methacrylate-ethylene dimethacrylate copolymer modified with ethylenediamine was employed for the isolation of platinum metals. The sorption selectivity coefficients for Rh(III), Ir(IV), Pt(IV) and Pd(II) chloro complexes were determined in the static mode and the values of KRhIr = 10·9, KIrPt = 5·4 and KIrPd = 7·3 were obtained. The dependence of the sorption capacity of the resin on pH of the sorption solution was established; the highest sorption capacity for palladium, 1·7 mmol g-1, was found at pH 3. A procedure for the separation of iridium from palladium is suggested making use of the complexing ability of the sorbent. UV-VIS spectroscopic measurements revealed that Ir(IV) is reduced to Ir(III) on the sorbent and [IrCl6]3- ions are formed. This reduction is caused by aquation of the hydrophilic particles of the sorbent with bonded [IrCl6]2- anions.
Application of an online team physician survey to the consensus statement on sideline preparedness: the medical bag's highly desired items: Table 1
Authors: Everline Clayton
Published: June 2010

Three major duties of the team physician, according to a consensus statement published in 2001, are ‘to plan and train for emergencies during competition and practice, address equipment and supply issues and provide for proper event coverage’. Various medical supplies have been consistently recommended in articles preceding and following the consensus statement while others have not. Nonetheless, there has never been an online survey of team physicians involved with the American Medical Society for Sports Medicine or the American Orthopaedic Society for Sports Medicine covering community, high school, collegiate and professional sporting events that documented the usage of supplies typically found in a team physician's main ‘medical bag’ by consensus standards. The purpose of this study was to document the usage frequencies of supplies listed as ‘highly desirable for the “medical bag” to include’ as well as stocking, storage and inventory maintenance protocols for these events and to compare them with recommendations from the consensus statement as well as some protocols involving prehospital care from a ‘wilderness’ perspective.
Coaches' perspectives on implementing an evidence-informed injury prevention programme in junior community netball
Authors: Saunders N , Otago L , Romiti M , Donaldson A , White P , Finch CF
Published: June 2010

Objective

For effective sports injury prevention, information is needed about the implementation context for interventions. This study describes coaches' feedback on the implementation of an evidence-informed injury prevention programme in community junior netball using coaches' perceptions and the RE–AIM framework.

Methods

A lower-limb injury prevention programme (Down to Earth; D2E), for teaching safe-landing techniques, was delivered to 31 coaches from 31 junior community netball teams in a 1-h workshop. Coaches then delivered a 6-week programme at team training sessions starting in the week before the competition season commenced. 65% of coaches completed a feedback survey 17 weeks after they had delivered the programme.

Results

Most (88%) coaches believed that D2E improved their players' ability to perform correct landing techniques in games and that players had retained these improvements over the season. The majority (83%) indicated that an improvement in player athletic attributes was the greatest advantage of D2E, followed by a reduction in injury risk. Identified barriers to implementing D2E were running out of time and very young players finding the drills too difficult. Coaches reported that they needed more ideas for training drills that could be incorporated into their programmes and believed that their own coaching training did not adequately prepare them to implement an injury prevention programme.

Conclusions

Although coaches believed that D2E was effective in developing correct landing techniques, some modifications are needed to make it more suitable for younger players and coach education by accreditation courses could be improved to support the implementation of injury prevention programmes.
Trajectories of cardiorespiratory fitness in children with and without developmental coordination disorder: a longitudinal analysis
Authors: Cairney John , Hay John , Veldhuizen Scott , Faught Brent E
Published: June 2010

Objective

To compare the longitudinal trajectories of cardiorespiratory fitness (CRF) in children with probable developmental coordination disorder (DCD) with those of typically developing children.

Setting

School-based study, conducted in a large region of Ontario, Canada. 75 out of a possible 92 schools (83%) consented to participate.

Participants

A cohort of children, enrolled in grade 4 (mean 9 years 11 months; SD 0.05) at baseline (n=2278) were followed twice-yearly over a 2-year period.

Measures

The short form of the Bruininks–Oseretsky test of motor proficiency was used to identify children with probable DCD and the Leger shuttle run to measure maximal oxygen uptake (VO2max).

Results

Mixed-effects modelling was used to estimate the change over time in predicted VO2max for both children with probable DCD and typically developing children. For all children, VO2max declined over time. Children (boys and girls) with probable DCD not only had lower VO2max at baseline compared with typically developing children, VO2max declined among these children at a much steeper rate.

Conclusion

Although previous research has found children with DCD to have poor CRF compared with typically developing children, most of this work has relied on cross-sectional designs to examine group differences. The results of this study confirm that differences in CRF between children with and without probable DCD persist over time, highlighting the concern that DCD is a risk factor for poor cardiovascular health in children.
Doping is a threat to sporting excellence
Authors: Devine John William
Published: June 2010

Savulescuet alhave argued that the risk to athletes' welfare provides the only legitimate ground for restricting the use of performance enhancing drugs in sport. In this paper, it is argued that the idea of `sport', properly understood, provides further reason to impose such restrictions. A `balance of excellences' argument is proposed whereby doping is considered objectionable on account of its disrupting the relation between the excellences around which sporting competition is organised. We have reason to restrict the use of performance enhancing drugs in sport not only because of the threat they pose to athletes' health but also because of the threat they pose to athletes' displaying the relevant types of sporting excellence.
QUASI-NEUTRAL LIMIT OF THE MULTIDIMENSIONAL DRIFT-DIFFUSION MODELS FOR SEMICONDUCTORS
Authors: JU QIANGCHANG , WANG SHU
Published: June 2010

This paper is devoted to the rigorous justification of the quasi-neutral limit of bipolar transient drift-diffusion models for semiconductors with p–n junctions in the multidimensional space. The general initial data and smooth sign-changing doping profiles with good boundary conditions are considered. The limit is performed rigorously by using multiple scaling asymptotic analysis, in which one main point is the construction of a more accurate approximate solution involving the effect of initial layer. The uniform estimates with respect to the scaled Debye length are obtained through the elaborate energy method and the relative entropy functional method.
A unifying approach to product-forms in networks with finite capacity constraints
Authors: Balsamo Simonetta , Harrison Peter G. , Marin Andrea
Published: June 2010

In queueing networks with blocking, stations wishing to transmit customers to a full queue are blocked and need to take alternative action on completing a service. In general, product-forms, i.e. separable solutions for such a network's equilibrium state probabilities, do not exist but some product-forms have been obtained over the years in special cases, using a variety of techniques. We show that the Reversed Compound Agent Theorem (RCAT) can obtain these diverse results in a uniform way by its direct application, so unifying product-forms in networks with and without blocking. New product-forms are also constructed for a type of blocking we call `skipping', where a blocked station sends its output-customers to the queue after the one causing the blocking in that customer's path. Finally, we investigate a novel congestion management scheme for networks of finite-capacity queues in which a station with a full queue transmits signals that delete customers from upstream queues in order to reduce incoming traffic.
On the flow-level dynamics of a packet-switched network
Authors: Moallemi Ciamac , Shah Devavrat
Published: June 2010

The packet is the fundamental unit of transportation in modern communication networks such as the Internet. Physical layer scheduling decisions are made at the level of packets, and packet-level models with exogenous arrival processes have long been employed to study network performance, as well as design scheduling policies that more efficiently utilize network resources. On the other hand, a user of the network is more concerned with end-to-end bandwidth, which is allocated through congestion control policies such as TCP. Utility-based flow-level models have played an important role in understanding congestion control protocols. In summary, these two classes of models have provided separate insights for flow-level and packet-level dynamics of a network. In this paper, we wish to study these two dynamics together. We propose a joint flow-level and packet-level stochastic model for the dynamics of a network, and an associated policy for congestion control and packet scheduling that is based on alpha-weighted policies from the literature. We provide a fluid analysis for the model that establishes the throughput optimality of the proposed policy, thus validating prior insights based on separate packet-level and flow-level models. By analyzing a critically scaled fluid model under the proposed policy, we provide constant factor performance bounds on the delay performance and characterize the invariant states of the system.
Coloring spatial point processes with applications to peer discovery in large wireless networks
Authors: Ni Jian , Srikant R. , Wu Xinzhou
Published: June 2010

In this paper, we study distributed channel assignment in wireless networks with applications to peer discovery in ad hoc wireless networks. We model channel assignment as a coloring problem for spatial point processes in which n nodes are located in a unit cube uniformly at random and each node is assigned one of K colors, where each color represents a channel. The objective is to maximize the spatial separation between nodes of the same color. In general, it is hard to derive the optimal coloring algorithm and therefore, we consider a natural greedy coloring algorithm, first proposed in [5]. We prove two key results: (i) with just a small number of colors when K is roughly of the order of log(n) loglog(n), the distance separation achieved by the greedy coloring algorithm asymptotically matches the optimal distance separation that can be achieved by an algorithm which is allowed to select the locations of the nodes but is allowed to use only one color, and (ii) when K = Omega(log(n)), the greedy coloring algorithm asymptotically achieves the best distance separation that can be achieved by an algorithm which is allowed to both optimally color and place nodes. The greedy coloring algorithm is also shown to dramatically outperform a simple random coloring algorithm. Moreover, the results continue to hold under node mobilities.
Scheduling in multichannel wireless networks with flow-level dynamics
Authors: Liu Shihuan , Ying Lei , Srikant R.
Published: June 2010

This paper studies scheduling in multichannel wireless networks with flow-level dynamics. We consider a downlink network with a single base station, M channels (frequency bands), and multiple mobile users (flows). We also assume mobiles dynamically join the network to receive finite-size files and leave after downloading the complete files. A recent study [16] has shown that the MaxWeight algorithm fails to be throughput-optimal under this flow-level dynamics. The main contribution of this paper is the development of joint channel-assignment and workload-based scheduling algorithms for multichannel downlink networks with dynamic flow arrivals/departures. We prove that these algorithms are throughput-optimal. Our simulations further demonstrate that a hybrid channel-assignment and workload-based scheduling algorithm significantly improves the network performance (in terms of both file-transfer delay and blocking probability) compared to the existing algorithms.
Incentivizing peer-assisted services
Authors: Misra Vishal , Ioannidis Stratis , Chaintreau Augustin , Massoulié Laurent
Published: June 2010

A new generation of content delivery networks for live streaming, video on demand, and software updates takes advantage of a peer-to-peer architecture to reduce their operating cost. In contrast with previous uncoordinated peer-to-peer schemes, users opt-in to dedicate part of the resources they own to help the content delivery, in exchange for receiving the same service at a reduced price. Such incentive mechanisms are appealing, as they simplify coordination and accounting. However, they also increase a user's expectation that she will receive a fair price for the resources she provides. Addressing this issue carefully is critical in ensuring that all interested parties--including the provider--are willing to participate in such a system, thereby guaranteeing its stability.

In this paper, we take a cooperative game theory approach to identify the ideal incentive structure that follows the axioms formulated by Lloyd Shapley. This ensures that each player, be it the provider or a peer, receives an amount proportional to its contribution and bargaining power when entering the game. In general, the drawback of this ideal incentive structure is its computational complexity. However, we prove that as the number of peers receiving the service becomes large, the Shapley value received by each player approaches a fluid limit. This limit follows a simple closed form expression and can be computed in several scenarios of interest: by applying our technique, we show that several peer-assisted services, deployed on both wired and wireless networks, can benefit from important cost and energy savings with a proper incentive structure that follows simple compensation rules.
Detecting traffic anomalies using an equilibrium property
Authors: Silveira Fernando , Diot Christophe , Taft Nina , Govindan Ramesh
Published: June 2010

When many flows are multiplexed on a non-saturated link, their volume changes over short timescales tend to cancel each other out, making the average change across flows close to zero. This equilibrium property holds if the flows are nearly independent, and it is violated by traffic changes caused by several correlated flows. We exploit this empirical property to design a computationally simple anomaly detection method.
Nucleoside/nucleobase transport and metabolism by microvascular endothelial cells isolated from ENT1−/−mice
Authors: Bone Derek B. J. , Choi Doo-Sup , Coe Imogen R. , Hammond James R.
Published: June 2010

Nucleoside and nucleobase uptake is integral to mammalian cell function, and its disruption has significant effects on the cardiovasculature. The predominant transporters in this regard are the equilibrative nucleoside transporter subtypes 1 (ENT1) and 2 (ENT2). To examine the role of ENT1 in more detail, we have assessed the mechanisms by which microvascular endothelial cells (MVECs) from ENT1−/−mice transport and metabolize nucleosides and nucleobases. Wild-type murine MVECs express mainly the ENT1 subtype with only trace levels of ENT2. These cells also have a Na+-independent equilibrative nucleobase transport mechanism for hypoxanthine (ENBT1). In the ENT1−/−cells, there is no change in ENT2 or ENBT1, resulting in a very low level of nucleoside uptake in these cells, but a high capacity for nucleobase accumulation. Whereas there were no significant changes in nucleoside transporter subtype expression, there was a dramatic increase in adenosine deaminase and adenosine A2areceptors (both transcript and protein) in the ENT1−/−tissues compared with WT. These changes in adenosine deaminase and A2areceptors likely reflect adaptive cellular mechanisms in response to reduced adenosine flux across the membranes of ENT1−/−cells. Our study also revealed that mouse MVECs have a nucleoside/nucleobase transport profile that is more similar to human MVECs than to rat MVECs. Thus mouse MVECs from transgenic animals may prove to be a useful preclinical model for studies of the effects of purine metabolite modifiers on vascular function.
Phospholemman Ser69 phosphorylation contributes to sildenafil-induced cardioprotection against reperfusion injury
Authors: Madhani Melanie , Hall Andrew R. , Cuello Friederike , Charles Rebecca L. , Burgoyne Joseph R. , Fuller William , Hobbs Adrian J. , Shattock Michael J. , Eaton Philip
Published: June 2010

The phosphodiesterase type-5 inhibitor sildenafil has powerful cardioprotective effects against ischemia-reperfusion injury. PKG-mediated signaling has been implicated in this protection, although the mechanism and the downstream targets of this kinase remain to be fully elucidated. In this study we assessed the role of phospholemman (PLM) phosphorylation, which activates the Na+/K+-ATPase, in cardioprotection afforded by sildenafil administered during reperfusion. Isolated perfused mouse hearts were optimally protected against infarction (indexed by tetrazolium staining) by 0.1 μM sildenafil treatment during the first 10 min of reperfusion. Extended sildenafil treatment (30, 60, or 120 min at reperfusion) did not alter the degree of protection provided. This protection was PKG dependent, since it was blocked by KT-5823. Western blot analysis using phosphospecific antibodies to PLM showed that sildenafil at reperfusion did not modulate PLM Ser63 or Ser68 phosphorylation but significantly increased Ser69 phosphorylation. The treatment of isolated rat ventricular myocytes with sildenafil or 8-bromo-cGMP (PKG agonist) enhanced PLM Ser69 phosphorylation, which was bisindolylmaleimide (PKC inhibitor) sensitive. Patch-clamp studies showed that sildenafil treatment also activated the Na+/K+-ATPase, which is anticipated in light of PLM Ser69 phosphorylation. Na+/K+-ATPase activation during reperfusion would attenuate Na+overload at this time, providing a molecular explanation of how sildenafil guards against injury at this time. Indeed, using flame photometry and rubidium uptake into isolated mouse hearts, we found that sildenafil enhanced Na+/K+-ATPase activity during reperfusion. In this study we provide a molecular explanation of how sildenafil guards against myocardial injury during postischemic reperfusion.
Na+-K+-ATPase and Ca2+clearance proteins in smooth muscle: a functional unit
Authors: Pritchard Tracy J. , Bowman Peggy Sue , Jefferson Andrew , Tosun Metiner , Lynch Ronald M. , Paul Richard J.
Published: June 2010

The Na+-K+-ATPase (NKA) can affect intracellular Ca2+concentration regulation via coupling to the Na+-Ca2+exchanger and may be important in myogenic tone. We previously reported that in mice carrying a transgene for the NKA α2-isoform in smooth muscle (α2sm+), the α2-isoform protein as well as the α1-isoform (not contained in the transgene) increased to similar degrees (2–7-fold). Aortas from α2sm+mice relaxed faster from a KCl-induced contraction, hypothesized to be related to more rapid Ca2+clearance. To elucidate the mechanisms underlying this faster relaxation, we therefore measured the expression and distribution of proteins involved in Ca2+clearance. Na+-Ca2+exchanger, sarco(endo)plasmic reticulum Ca2+-ATPase (SERCA), and plasma membrane Ca2+-ATPase (PMCA) proteins were all elevated up to approximately fivefold, whereas actin, myosin light chain, and calponin proteins were not changed in smooth muscle from α2sm+mice. Interestingly, the corresponding Ca2+clearance mRNA levels were unchanged. Immunocytochemical data indicate that the Ca2+clearance proteins are distributed similarly in wild-type and α2sm+aorta cells. In studies measuring relaxation half-times from a KCl-induced contraction in the presence of pharmacological inhibitors of SERCA and PMCA, we estimated that together these proteins were responsible for ∼60–70% of relaxation in aorta. Moreover, the percent contribution of SERCA and PMCA to relaxation rates in α2sm+aorta was not significantly different from that in wild-type aorta. The coordinate expressions of NKA and Ca2+clearance proteins without change in the relative contributions of each individual protein to smooth muscle function suggest that NKA may be but one component of a larger functional Ca2+clearance system.
Neurotrophic and neuroimmune responses to early-life Pseudomonas aeruginosa infection in rat lungs
Authors: Cardenas Silvia , Scuri Mario , Samsell Lennie , Ducatman Barbara , Bejarano Pablo , Auais Alexander , Doud Melissa , Mathee Kalai , Piedimonte Giovanni
Published: June 2010

Early-life respiratory infection with Pseudomonas aeruginosa is common in children with cystic fibrosis or immune deficits. Although many of its clinical manifestations involve neural reflexes, little information is available on the peripheral nervous system of infected airways. This study sought to determine whether early-life infection triggers a neurogenic-mediated immunoinflammatory response, the mechanisms of this response, and its relationship with other immunoinflammatory pathways. Weanling and adult rats were inoculated with suspensions containing P. aeruginosa (PAO1) coated on alginate microspheres suspended in Tris-CaCl2buffer. Five days after infection, rats were injected with capsaicin to stimulate nociceptive nerves in the airway mucosa, and microvascular permeability was measured using Evans blue as a tracer. PAO1 increased neurogenic inflammation in the extra- and intrapulmonary compartments of weanlings but not in adults. The mechanism involves selective overexpression of NGF, which is critical for the local increase in microvascular permeability and for the infiltration of polymorphonuclear leukocytes into infected lung parenchyma. These effects are mediated in part by induction of downstream inflammatory cytokines and chemokines, especially IL-1β, IL-18, and leptin. Our data suggest that neurogenic-mediated immunoinflammatory mechanisms play important roles in airway inflammation and hyperreactivity associated with P. aeruginosa when infection occurs early in life.
Acute cigarette smoke inhalation blunts lung responsiveness to methacholine and allergen in rabbit: differentiation of central and peripheral effects
Authors: Porra Liisa , Peták Ferenc , Strengell Satu , Neitola Kimmo , Janosi Tibor Z. , Suhonen Heikki , Suortti Pekka , Sovijärvi Anssi R. A. , Habre Walid , Bayat Sam
Published: June 2010

Despite the prevalence of active smoking in asthmatics, data on the short-term effect of acute mainstream tobacco smoke exposure on airway responsiveness are very scarce. The aim of this study was to assess the immediate effect of acute exposure to mainstream cigarette smoke on airway reactivity to subsequent nonspecific and allergenic challenges in healthy control ( n = 5) and ovalbumin-sensitized rabbits ( n = 6). We combined low-frequency forced oscillations and synchrotron radiation CT imaging to differentiate central airway and peripheral airway and lung parenchymal components of the response to airway provocation. Acute exposure to smoke generated by four successive cigarettes (CS) strongly inhibited the central airway response to subsequent IV methacholine (MCh) challenge. In the sensitized animals, although the response to ovalbumin was also inhibited in the central airways, mainstream CS did not blunt the peripheral airway response in this group. In additional groups of experiments, exposure to HEPA-filtered CS ( n = 6) similarly inhibited the MCh response, whereas CO (10,000 ppm for 4 min, n = 6) or nitric oxide inhalation instead of CS (240 ppm, 4 × 7 min, n = 5) failed to blunt nonspecific airway responsiveness. Pretreatment with α-chymotrypsin to inhibit endogenous VIP before CS exposure had no effect ( n = 4). Based on these observations, the gas phase of mainstream cigarette smoke may contain one or more short-term inhibitory components acting primarily on central airways and inhibiting the response to both specific and nonspecific airway provocation, but not on the lung periphery where both lung mechanical parameters, and synchrotron-imaging derived parameters, showed large changes in response to allergen challenge in sensitized animals.
Calcium Signaling Through CatSper Channels in Mammalian Fertilization
Authors: Ren Dejian , Xia Jingsheng
Published: June 2010

The molecular mechanisms underlying Ca2+entry into sperm are now much more well defined thanks to direct recordings of mature sperm cells. This article reviews the function of a sperm-specific ion channel, CatSper. CatSpers have a clearly defined function in sperm's hyperactivated motility and are essential for male fertility. We propose that physiological stimuli such as zona pellucida and cyclic nucleotides induce Ca2+entry through CatSper channels instead of acting on CaVand CNG channels as previously thought.
Access for Laparoendoscopic Single Site Surgery
Authors: Ross Sharona B. , Clark C. Whalen , Morton Connor A. , Rosemurgy Alexander S.
Published: June 2010

Laparoscopic surgery is the standard of care for many abdominal and pelvic operations and is widely applied today. LESS (Laparo-Endoscopic Single Site) surgery, originally attempted in the 1990s, is an advanced minimally invasive approach that allows laparoscopic operations to be undertaken through a small (<15 mm) incision in the umbilicus, a preexisting scar. The presence of a preexisting scar allows LESS surgery to be essentially scarless, which is the key benefit to LESS operations. Herein, we review our experience with over 500 LESS operations and discuss the key techniques to establishing access to the peritoneal cavity. We review the options for obtaining access, available instrumentation, common challenges and solutions for access. We conclude that LESS surgery is safe and provides outcomes with superior cosmesis relative to conventional laparoscopy. LESS surgery should be embraced, as patient demand is rapidly increasing.
Phase II Trial of Short-Course R-Chop Followed by 90Y-Ibritumomab Tiuxetan in Previously Untreated High-Risk Elderly Diffuse Large B-Cell Lymphoma Patients
Authors: Zinzani Pier Luigi , Rossi Giuseppe , Franceschetti Silvia , Botto Barbara , Di Rocco Alice , Cabras Maria Giuseppina , Petti Maria Concetta , Stefoni Vittorio , Broccoli Alessandro , Fanti Stefano , Pellegrini Cinzia , Montini Gian Carlo , Gandolfi Letizia , Derenzini Enrico , Argnani Lisa , Fina Mariapaola , Tucci Alessandra , Bottelli Chiara , Pileri Stefano , Baccarani Michele
Published: June 2010

Purpose: This study aimed to evaluate the efficacy and safety of the treatment with 90Y-ibritumomab tiuxetan following a short-course of rituximab with cyclophosphamide-adriamycin-vincristine-prednisone (R-CHOP) in high-risk elderly patients with previously untreated diffuse large B-cell lymphoma (DLBCL).

Experimental Design: From December 2006 to October 2008, 55 high-risk elderly (age ≥60 years) untreated DLBCL patients were treated in seven Italian institutions with a short-course of chemotherapy consisting of four cycles of R-CHOP21 followed by 90Y-ibritumomab tiuxetan 6 to 10 weeks later.

Results: Of the 55 patients, 48 underwent radioimmunotherapy. The overall response rate to the entire treatment regimen was 80%, including 73% complete remissions and 7% partial remissions. Eight (50%) of the 16 patients who achieved less than a complete response with CHOP improved their remission status after 90Y-ibritumomab tiuxetan administration. With a median follow-up of 18 months, the 2-year progression-free survival was estimated to be 85%, with a 2-year overall survival of 86%. 90Y-ibritumomab tiuxetan toxicity consisted of grade 3 to 4 hematologic toxicity in 28 of 48 patients, mainly neutropenia (23 patients) and thrombocytopenia (15 patients). Red cells and/or platelets transfusions were given to three patients.

Conclusion: This study evaluated the feasibility, efficacy, and safety of a short-course R-CHOP21 regimen followed by 90Y-ibritumomab tiuxetan in high-risk elderly DLBCL patients. Clin Cancer Res; 16(15); 3998–4004. ©2010 AACR.
Cytotoxicity of Activated Natural Killer Cells against Pediatric Solid Tumors
Authors: Cho Duck , Shook David R. , Shimasaki Noriko , Chang Yu-Hsiang , Fujisaki Hiroyuki , Campana Dario
Published: June 2010

Purpose: To develop new therapies for children with solid tumors, we tested the cytotoxicity of natural killer (NK) cells expanded by coculture with K562-mb15-41BBL cells. We sought to identify the most sensitive tumor subtypes, clarify the molecular interactions regulating cytotoxicity, and determine NK antitumor potential in vivo.

Experimental Design: We tested in vitro cytotoxicity of expanded NK cells against cell lines representative of Ewing sarcoma (EWS; n = 5), rhabdomyosarcoma (n = 4), neuroblastoma (n = 3), and osteosarcoma (n = 3), and correlated the results with expression of inhibitory and activating NK receptor ligands. We also compared expanded and primary NK cells, determined the effects of activating receptor ligation and of chemotherapeutic drugs, and assessed the therapeutic effect of NK cell infusions in xenografts.

Results: In 45 experiments, EWS and rhabdomyosarcoma cell lines were remarkably sensitive to expanded NK cells, with median cytotoxicities at 1:1 effector/target ratio of 87.2% and 79.1%, respectively. Cytotoxicity was not related to levels of expression of NK receptor ligands, nor was it affected by pretreatment of target cells with daunorubicin or vincristine, but was markedly inhibited by preincubation of NK cells with a combination of antibodies against the NK-activating receptors NKGD2 and DNAM-1. Expanded NK cells were considerably more cytototoxic than unstimulated NK cells, and eradicated EWS cells engrafted in nonobese diabetic/severe combined immunodeficient Il2rgnull mice.

Conclusions: Among pediatric solid tumors, EWS and rhabdomyosarcoma are exquisitely sensitive to expanded NK cells. The NK expansion method described here has been adapted to large-scale conditions and supports a phase I clinical study including patients with these malignancies. Clin Cancer Res; 16(15); 3901–9. ©2010 AACR.
Survival of Kidney Transplantation Patients in the United States After Cardiac Valve Replacement
Authors: Sharma Alok , Gilbertson David T. , Herzog Charles A.
Published: June 2010

Background—

Few published studies address the survival of kidney transplantation patients after valve surgery, and none address relative outcomes related to tissue versus nontissue prosthesis. This study aimed to assess survival of US kidney transplantation patients after cardiac valve replacement and to compare associations of valve selection.

Methods and Results—

Of 1 698 706 patients in the US Renal Data System database, we identified 1335 kidney transplantation patients hospitalized in 1991 to 2004 for cardiac valve replacement. Survival was estimated by the Kaplan-Meier method; independent predictors of death were examined in a comorbidity-adjusted (by Charlson and propensity score) Cox model. Of the cohort, 17% were 0 to 44 years of age, 50% were 45 to 64 years of age, 28% were 65 to 74 years of age, and 5% were ≥75 years of age; 78% were white; 63% were men; and 20% had kidney failure caused by diabetes mellitus. Of 369 patients (28%) who received tissue valves, 75% had aortic valve replacement, 20% had mitral valve replacement, and 5% had both. Use of tissue valves increased from 13% in 1991 to 1995 to 38% in 2000 to 2004. Age, diabetes mellitus, and combined aortic and mitral valve replacement were the strongest predictors of all-cause mortality. In-hospital mortality was 14.0% overall, 11.4% for tissue-valve patients, and 15.0% for nontissue-valve patients (
P
=0.09). Two-year survival estimates were 61.5% for tissue-valve and 59.5% for nontissue-valve patients (
P
=0.30). The adjusted hazard ratio of death for tissue- versus nontissue-valve patients was 0.83 (95% confidence interval, 0.70 to 0.99).

Conclusions—

Renal transplantation patients requiring valve replacement have high mortality rates (≈20%/y). These data suggest minimally reduced mortality risk for patients receiving tissue versus nontissue valves.
Historical and Future Land-Cover Change in a Municipality of Ghana
Authors: Attua Emmanuel M. , Fisher Joshua B.
Published: June 2010

Urban land-cover change is increasing dramatically in most developing nations. In Africa and in the New Juaben municipality of Ghana in particular, political stability and active socioeconomic progress has pushed the urban frontier into the countryside at the expense of the natural ecosystems at ever-increasing rates. Using Landsat satellite imagery from 1985 to 2003, the study found that the urban core expanded by 10% and the peri-urban areas expanded by 25% over the period. Projecting forward to 2015, it is expected that urban infrastructure will constitute 70% of the total land area in the municipality. Giving way to urban expansion were losses in open woodlands (19%), tree fallow (9%), croplands (4%), and grass fallow (3%), with further declines expected for 2015. Major drivers of land-cover changes are attributed to demographic changes and past microeconomic policies, particularly the Structural Adjustment Programme (SAP); the Economic Recovery Programme (ERP); and, more recently, the Ghana Poverty Reduction Strategy (GPRS). Pluralistic land administration, complications in the land tenure systems, institutional inefficiencies, and lack of capacity in land administration were also key drivers of land-cover changes in the New Juaben municipality. Policy recommendations are presented to address the associated challenges.
Formative Measurement and Academic Research: In Search of Measurement Theory
Authors: Hardin Andrew M. , Chang Jerry Cha-Jan , Fuller Mark A. , Torkzadeh Gholamreza
Published: June 2010

The use of causal indicators to formatively measure latent constructs appears to be on the rise, despite what appears to be a troubling lack of consistency in their application. Scholars in any discipline are responsible not only for advancing theoretical knowledge in their domain of study but also for addressing methodological issues that threaten that advance. In that spirit, the current study traces causal indicators from their origins in causal modeling to their use in structural equation modeling today. Conclusions from this review suggest that unlike effect (reflective) indicators, whose application is based on classical test theory, today’s application of causal (formative) indicators is based on research demonstrating their practical application rather than on psychometric theory supporting their use. The authors suggest that this lack of theory has contributed to the confusion surrounding their implementation. Recent research has questioned the generalizability of formatively measured latent constructs. In the current study, the authors discuss how the use of fixed-weight composites may be one way to employ causal indicators so that they may be generalized to additional contexts. More specifically, they suggest the use of meta-analysis principles for identifying optimum causal indicator weights that can be used to generate fixed-weight composites. Finally, the authors explain how these fixed-weight composites can be implemented in both components-based and covariance-based statistical packages. Implications for the use of causal indicators in academic research are used to focus these discussions.
Hospitality, Culture and Regeneration: Urban Decay, Entrepreneurship and the ‘Ruin’ Bars of Budapest
Authors: Lugosi Peter , Bell David , Lugosi Krisztina
Published: June 2010

This paper considers the relationships between hospitality, culture and urban regeneration through an examination of rom (ruin) venues, which operate in dilapidated buildings in Budapest, Hungary. The paper reviews previous work on culture and urban regeneration in order to locate the role of hospitality within emerging debates. It subsequently interrogates the evolution of the rom phenomenon and demonstrates how, in this context, hospitality thrives because of social and physical decay in urban locations, how operators and entrepreneurs exploit conflicts among various actors involved in regeneration and how hospitality may be mobilised purposefully in the regeneration process. The paper demonstrates how networked entrepreneurship maintains these operations and how various forms of cultural production are entangled and mobilised in the venues’ hospitality propositions.
Rawlsian Theory and the Circumstances of Politics
Authors: Mason Andrew
Published: June 2010

Can Rawlsian theory provide us with an adequate response to the practical question of how we should proceed in the face of widespread and intractable disagreement over matters of justice? Recent criticism of ideal theorizing might make us wonder whether this question highlights another way in which ideal theory can be too far removed from our non-ideal circumstances to provide any practical guidance. Further reflection on it does not show that ideal theory is redundant, but it does indicate that there is a need for a nonideal theory that does not consist simply in an account of how to apply the principles which are yielded by ideal theory to non-ideal circumstances in the light of what is feasible and an assessment of the costs of implementation. Indeed any non-ideal theory that can adequately address this question will have to be partially autonomous, drawing on a notion of legitimacy that is rather different to the one which lies at the heart of Rawlsian ideal theory.
Dealing with Urban Diversity: Promises and Challenges of City Life for Intercultural Citizenship
Authors: van Leeuwen Bart
Published: June 2010

Intercultural citizenship seems to benefit from certain generic aspects of city life that carry a negative quality, such as “blasé attitude” or the typical “indifference” of city dwellers. The main part of this essay argues that this observation allows the formulation of a moral minimum—a threshold conception—of intercultural citizenship in the urban setting, namely, what I call side-by-side citizenship. A certain level of indifference makes possible personal freedom and a tolerant multicultural city, although there are more ideal formulations of intercultural citizenship, such as in terms of agonism or cosmopolitanism. However, these more ambitious forms easily become too demanding given the muddle of everyday urban living conditions, which tend to promote mutual reserve and impersonal social relations. A modest and realistic conception of intercultural citizenship could prove crucial in motivating citizens to act according to some minimal standards.
Testing Moderating Hypotheses in Limited Dependent Variable and Other Nonlinear Models
Authors: Bowen Harry P.
Published: June 2010

The use of limited dependent variable (LDV) models is becoming ubiquitous in empirical management research. When using such models, researchers frequently postulate and test that the relationship between an explanatory variable and the dependent variable is moderated by another variable by including in the model an interaction variable. Although recent papers clarify methods for analyzing a moderating effect in LDV models, it is not widely appreciated that this effect confounds two moderating effects: one associated with including an interaction variable in the model and one associated with the inherent nonlinearity of such models. This article presents a method to separate these two sources of a moderating effect for a general class of nonlinear models that includes all LDV models commonly used in the management literature. For such models, the article demonstrates that the statistically correct method to assess the validity of a moderating hypothesis is not, as currently recommended, to test for significance of the total moderating effect derived from the model that includes the interaction variable but instead to test for significance of the secondary moderating effect, the latter defined as the difference between two moderating effects: the one in the model that includes the interaction variable and the one in the model that excludes this variable. The result that the secondary effect is the correct statistic for testing a moderating hypothesis is very general, and it applies whenever a moderating hypothesis is to be tested by including an interaction variable in any model, whether linear or nonlinear.