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This paper presents a general framework for the motion design of cam mechanisms using Non-Uniform Rational B-Spline (NURBS). The follower motion is described by the NURBS function. To establish motion curves, the system of linear equations is set up by arbitrary boundary conditions of the follower motion on displacements, velocities, accelerations, and jerks. Moreover, the computation of the NURBS parameters (the knot vector and the weight factor) is formulated in order to reduce peak values of the acceleration and jerk. The example demonstrates that the motion curves used by NURBS obtain advantageous characteristics and the maximum values of the acceleration and jerk on the motion curves decrease considerably compared with the polynomial and B-spline functions. Therefore, inertial forces and the tendency of vibration can be reduced in cam dynamics of high-speed cam systems. The results show that using NURBS for synthesizing motion curves is robust and effective because this can be applied for arbitrary motion curves of cam mechanisms. [ABSTRACT FROM AUTHOR]

In several previous studies emission of ozone (O 3 ) during fireworks has been reported, which was attributed to either photolysis of molecular oxygen (O 2 ) or nitrogen dioxide (NO 2 ) by short/near UV radiation emitted during the high-temperature combustion of fireworks. In contrast, in the present study no O 3 formation was observed using a selective O 3 -LOPAP instrument during the combustion of pyrotechnical material in the laboratory, while a standard O 3 monitor using UV absorption showed extremely high O 3 signals. The artificial O 3 response of the standard O 3 monitor was caused by known interferences associated with high levels of co-emitted VOCs and could also be confirmed in field measurements during New Year's Eve in the city of Wuppertal, Germany. The present results help to explain unreasonably high ozone levels documented during ambient fireworks, which are in contradiction to the fast titration of O 3 by nitrogen monoxide (NO) in the night-time atmosphere. [ABSTRACT FROM AUTHOR]

Adults and subadults recovered from the Late Woodland period (∼A.D. 800–1100) Schroeder Mounds site (11HE177) from west-central Illinois who preserve permanent incisors and/or canines (N = 46) were examined for the presence of macroscopically visible linear enamel hypoplasia (LEH) by case, by tooth type, number of hypoplastic defects by tooth type, and estimated developmental age of occurrence. The raw case frequency of LEH (16/46) is 34.8 percent. The Schroeder Mounds subadults (N = 15) have a higher case frequency (i.e., 60 percent versus 22.6 percent), number of stress episodes per tooth, and a longer developmental age range of hypoplastic defects than the adults. With no subsistence or settlement context, the Schroeder Mounds sample was compared to published (solely) adult LEH data from eight western Illinois sites segregable as either Middle (∼50 B.C.–A.D. 400) and Late Woodland period semi-sedentary forager-horticulturalists or Mississippian period (∼A.D. 1150–1250) sedentary (i.e., large aggregated village) maize-intensive agriculturalists. The adult Schroeder Mounds LEH patterns align with the Woodland samples with minor differences inclining the Schroeder sample toward a forager-farmer subsistence/settlement strategy. The Schroeder Mounds subadult patterns and prevalence may reflect factors that contributed toward their early death. Whether these factors can be framed by the subsistence/settlement system will require comparative data. [ABSTRACT FROM AUTHOR]

During the European Life+ project PhotoPAQ (Demonstration of Photocatalytic remediation Processes on Air Quality), photocatalytic remediation of nitrogen oxides (NO x ) was studied in the Leopold II tunnel in Brussels, Belgium, using photocatalytic cementitious coating materials and an artificial UV lighting system. Three different approaches were used to quantify the pollution reduction, i.e. measurements before/after application, upwind/downwind of the test section and with UV lamps on/off . In contrast to first estimations based on laboratory studies on fresh samples, the field results showed no observable reduction of NO x in the tunnel. An upper limit of 2% was determined for the maximum possible NO x reduction, which corresponds to the experimental uncertainties. Serious passivation of the surface reactivity under the heavily polluted tunnel conditions by one order of magnitude was identified in laboratory experiments subsequent to the tunnel study as the main reason for the observed low remediation. In addition, high relative humidity and wind speed inside the tunnel further limited the photocatalytic uptake of NO x . When using the uptake kinetics from the laboratory experiments on passivized tunnel samples, simple model calculations based on a first order reaction kinetics indicate only an upper limit photocatalytic remediation inside the 160 m tunnel section of 0.4%, which is clearly below the experimental uncertainties and thus, in excellent agreement with the tunnel results. Optimized experimental conditions, for which this technology might be applicable in road tunnels, are discussed. [ABSTRACT FROM AUTHOR]

Abstract: The hard tick Ixodes ricinus is the principal vector of Lyme borreliosis (LB) group spirochaetes in Europe, but it also transmits a large number of other microbial pathogens that are of importance to animal and human health. Here, we characterise geographically distinct populations of this important ectoparasite based on multilocus sequence typing (MLST) of multiple mitochondrial (mt) genes (mtMLST). Internal fragments of approximately 500bp were amplified and sequenced for 6 protein-encoding and ribosomal genes (atp6, coi, coii, coiii, cytB, and 12s). The samples analysed consisted of 506 questing nymphs collected in Britain and Latvia in 2006–2008 and in Latvia in 2002. Although little genetic structure has previously been observed in I. ricinus ticks among Europe, our data could clearly differentiate these 2 populations. Here, we argue that this novel scheme provides additional phylogenetic resolution which is important for understanding the genetic and geographic structure of I. ricinus populations. This in turn will benefit monitoring and management of tick-borne diseases. [Copyright &y& Elsevier]

The article explores the use of reliable instrumentation and guide systems in unicondylar knee arthroplasty (UKA). Topics discussed include indications for the procedure, guide systems used in various surgical techniques associated with UKA and complications that could possible arise from UKA. Also included are tables showing the outcomes and complication of UKA based on various studies.

Abstract: Different GRACE data analysis centers provide temporal variations of the Earth''s gravity field as monthly, 10-daily or weekly solutions. These temporal mean fields cannot model the variations occurring during the respective time span. The aim of our approach is to extract as much temporal information as possible out of the given GRACE data. Therefore the temporal resolution shall be increased with the goal to derive daily snapshots. Yet, such an increase in temporal resolution is accompanied by a loss of redundancy and therefore in a reduced accuracy if the daily solutions are calculated individually. The approach presented here therefore introduces spatial and temporal correlations of the expected gravity field signal derived from geophysical models in addition to the daily observations, thus effectively constraining the spatial and temporal evolution of the GRACE solution. The GRACE data processing is then performed within the framework of a Kalman filter and smoother estimation procedure. The approach is at first investigated in a closed-loop simulation scenario and then applied to the original GRACE observations (level-1B data) to calculate daily solutions as part of the gravity field model ITG-Grace2010. Finally, the daily models are compared to vertical GPS station displacements and ocean bottom pressure observations. From these comparisons it can be concluded that particular in higher latitudes the daily solutions contain high-frequent temporal gravity field information and represent an improvement to existing geophysical models. [Copyright &y& Elsevier]

Abstract: Plasmid profiles of 2 Portuguese Borrelia lusitaniae strains, one isolated from a human patient and the other one from an Ixodes ricinus tick, were obtained by pulsed-field gel electrophoresis to evaluate the plasmid diversity in each strain. Overall, a maximum of 6 plasmids were detected that ranged from 19kb to 76kb, revealing completely different plasmid profiles from those previously described for other genospecies of B. burgdorferi sensu lato, the causative agents of Lyme borreliosis. The plasmid location of the ospA gene was investigated by hybridization, allowing its allocation to the plasmid of 70kb instead of the 54kb linear plasmid described for B. burgdorferi sensu stricto strains. [Copyright &y& Elsevier]

Abstract: The paper examines the impact of tax rule uncertainty on the development of the Sarbanes-Oxley auditor independence rules. We show that the inability of Congress to articulate a concise and agreed-upon tax shelter definition forced the SEC to adopt their own definition that incorporates two characteristics common to most tax shelters: contingent fee arrangements and confidentiality. We also consider whether this definition eliminates the subjectivity in the tax shelter identification process because it reinstates the significant purpose standard (used for tax enforcement purposes) to assist auditors (and their public company clients) identify tax shelter transactions. We conclude that the new definition has reduced the incentive of auditors to provide tax related services to their public company clients. [Copyright &y& Elsevier]

Abstract: This paper examines the accounting profession''s self-regulation of internal audit outsourcing services. The question of whether public accountants compromise their independence when they provide internal audit services to their attest clients was debated within the accounting and regulatory communities throughout the 1990s, and resulted in a confrontation between the accounting profession and the Securities and Exchange Commission in 2000. Internal audit outsourcing was a factor in the public perception of Arthur Andersen''s role in the collapse of Enron, and in lawmakers’ reaction to that event. It is specifically identified in the Sarbanes-Oxley Act of 2002 as a prohibited service that public accountants generally cannot provide to their public company external audit clients. Our purpose is to contribute an historical perspective to ongoing discussions about the efficacy of self-regulation by the public accounting profession. Self-regulation of internal audit outsourcing remains important because the Sarbanes-Oxley prohibition does not apply to auditors’ private company clients, and because the rules that the SEC issued to implement Sarbanes-Oxley seem to allow accounting firms to provide internal audit services to public company attest clients under a variety of circumstances that were not anticipated in the original legislation. Although accounting firms have not yet shown strong interest in testing the limits of the new rules, the firms may do so in the future. [Copyright &y& Elsevier]

Abstract: Non-methane hydrocarbons (NMHC) were measured vertically resolved up-wind and down-wind of the motorway BAB A656 Heidelberg–Mannheim, Germany, for 4 weeks in April and May 2001. The horizontal distribution of C2–C9 aliphatic and aromatic hydrocarbons was monitored by using two compact quasi on-line gas chromatography (GC) instruments. The vertical distribution of NMHC was determined by using adsorption tubes, which were analysed off-line by GC in the laboratory. More than 50 NMHC were detected and 26 of them were quantified. From the measured data, the emission source strength for a variety of NMHC were calculated and discussed. [Copyright &y& Elsevier]

Simultaneous nighttime HONO, NO, NO2 and particle surface area density gradients in the altitude range 10–190 m were measured for the first time on the meteorological tower at the Forschungszentrum Karlsruhe/Germany using a new, very sensitive HONO instrument, a commercial NOx monitor and a SMPS system. For all gradient measurements during the campaign it was observed that the [HONO]/[NO2] ratio decreased with increasing altitude below 100 m. In contrast, the particle surface area density was found to be more or less constant. Accordingly, no correlation between the [HONO]/[NO2] ratio and the particle surface area density was observed showing that HONO formation was dominated by processes on ground surfaces and that significant HONO formation on particle surfaces could be excluded for the measurement site. Besides the nighttime gradient measurements, high daytime HONO concentrations were observed at constant altitude, which point to a significant and yet unknown daytime source of HONO. In addition, a HONO/NOx ratio from direct emissions of 0.8% was estimated from the field campaign. [Copyright &y& Elsevier]

Borrelia burgdorferi sensu lato (s.l.), the tick-borne agent of Lyme borreliosis, is a bacterial species complex comprising 11 genospecies. Here, we discuss whether the delineation of genospecies is ecologically relevant. We provide evidence that B. burgdorferi s.l. is structured ecologically into distinct clusters that are host specific. An immunological model for niche adaptation is proposed that suggests the operation of complement-mediated selection in the midgut of the feeding tick. We conclude that vertebrate hosts rather than tick species are the key to Lyme borreliosis spirochaete diversity. [ABSTRACT FROM AUTHOR]

Toxicity thresholds for dissolved oil applied in tropical ocean risk assessments are largely based on the sensitivities of temperate and/or freshwater species. To explore the suitability of these thresholds for tropical habitats we experimentally determined toxicity thresholds for eight tropical species for a partially weathered gas condensate, applied the target lipid model (TLM) to predict toxicity of fresh and weathered condensates and compared sensitivities of the tropical species with model predictions. The experimental condensate-specific hazard concentration (HC5) was 167 μg L−1 total aromatic hydrocarbons (TAH), with the TLM-modelled HC5 (78 μg L−1 TAH) being more conservative, supporting TLM-modelled thresholds for tropical application. Putative species-specific critical target lipid body burdens (CTLBBs) indicated that several of the species tested were among the more sensitive species in the TLM database ranging from 5.1 (coral larvae) to 97 (sponge larvae) μmol g−1 octanol and can be applied in modelling risk for tropical marine ecosystems. [Display omitted] • Toxicity thresholds used for oil spill risk assessments primarily based on toxicity data for non-tropical species • Experimental toxicity data for tropical species compared with target lipid model predictions • Experimental and modelled toxicity thresholds for condensate oil agreed within factor of two • Toxicity modelling found suitable for deriving screening toxicity thresholds for tropical oceans • Further toxicity data and modelling for tropical species that include ultraviolet light exposures needed [ABSTRACT FROM AUTHOR]

Abstract: The roles of selection and migration of B. burgdorferi s. l. were studied. Questing adult Ixodes ricinus ticks were collected across Europe and analysed for infection with B. burgdorferi s. l. Analysis of the genospecies in individual ticks showed that B. garinii and B. valaisiana segregate from B. afzelii. Segregation of bird- and rodent-associated Borrelia genotypes can be explained by the operation of complement-mediated selection in the midgut of the feeding tick. Phylogenese analyses of B. burgdorferi s. l. indicate high rates of migration for bird-associated genotypes. Altogether, it is emerging that the ecology of Lyme borreliosis is largely host-driven and that selection and migration are major forces shaping the population structures of B. burgdorferi s. l. [Copyright &y& Elsevier]

This paper proposes a vertical planar 2 P RP-2 P PR parallel manipulator along with a serial planar RRR passive orthosis (exoskeleton/supporting system) for performing sitting/lying type (stationary trainer) lower limb rehabilitation therapies in the sagittal plane. Proposed system's kinematic arrangement along with forward and inverse solutions is presented. System dynamics is derived to understand the behavior of the over-constrained manipulator-orthosis system. Further, a robust motion control scheme is proposed and the motion control scheme is based on non-singular fast terminal sliding mode control along with a nonlinear disturbance observer. The effectiveness and usefulness of the proposed manipulator is shown with the implementation of the motion controller through computer based numerical simulations using a clinical gait motion pattern. The proposed motion control scheme is also validated on an in-house fabricated prototype through motion control experiments. The controller parameter sensitivity and controller robustness are further analyzed at different working conditions. In comparison to the conventional controllers, the proposed control scheme possess few advantages namely better robustness, less chattering, high precision and fast finite time convergence, and can work in the presence of parameter uncertainties. From the demonstration, the proposed manipulator has certain advantages over existing stationary lower limb rehabilitation trainers namely, simple design, larger workspace, higher stiffness, modular design and low cost. [ABSTRACT FROM AUTHOR]

Integrins are transmembrane heterodimeric glycoproteins, present in most cell types that act as mechanoreceptors, connecting extracellular matrix proteins to the cytoskeleton of the cell, mediating several physiological and pathological processes. The disintegrins are peptides capable of modulating the activity of integrins, such as αIIbβ3, responsible for the platelet aggregation and αvβ3, related to angiogenesis. The aim of this study was to produce the recombinant disintegrin jarastatin (rJast), to evaluate its secondary structure and biological activity. rJast was expressed in the yeast Komagataella phaffii (earlier Pichia pastoris) purified using molecular exclusion chromatography and the internal sequence and molecular mass were confirmed by mass spectrometry. The yield was approximately 40 mg/L of culture. rJast inhibited platelet aggregation induced by 2–4 μM ADP, 10 nM thrombin, and 1 μg/mL collagen (IC 50 of 244.8 nM, 166.3 nM and 223.5 nM, respectively). It also blocked the adhesion of platelets to collagen under continuous flow in approximately 60% when used 1 μM. We also evaluated the effect of rJast on HMEC-1 cells. rJast significantly inhibited the adhesion of these cells to vitronectin, as well as cell migration (IC 50 1.77 μM) without changing the viability. Conclusions: rJast was successfully expressed with activity in human platelets aggregation identical to the native molecule. Also, rJast inhibits adhesion and migration of endothelial cells. Thus, being relevant for the development of anti-thrombotic and anti-angiogenic drugs. [Display omitted] • The disintegrin jarastatin (rJast) was expressed in the Pichia pastoris system. • rJast showed a similar effect in platelet aggregation assays than the native molecule. • rJast blocked adhesion of platelets to collagen underflow. • rJast also impaired endothelial cells (HMEC) migration. [ABSTRACT FROM AUTHOR]

Abstract: A simple O3-LOPAP (Long Path Absorption Photometer) instrument for the selective detection of O3 in the atmosphere is presented, which is mainly intended to be used as an extension of a recently developed NO2-LOPAP. O3 is sampled in a stripping coil by a selective chemical reaction with the highly absorbing Indigo dye. The reduction of the optical absorption of the dye is detected in a liquid core waveguide. The instrument has a detection limit of 0.4 ppbv, an accuracy of 10%, a precision of 2% for 6 min time resolution and allows the absolute quantification of O3 according to Lambert–Beer''s law. Interferences towards nitrogen oxides (NO and NO2), N2O5, H2O2 and several VOCs were quantified in the laboratory and found to be negligible for atmospheric conditions. The new instrument was successfully validated against a commercial UV-absorption instrument during an urban field campaign and against the FTIR technique in a smog chamber under complex photosmog conditions. For the UV-absorption instrument significant positive interferences towards aromatic species were observed in the smog chamber. [Copyright &y& Elsevier]

Abstract: Gradients of HONO, NOx (NO + NO2) and O3 were measured during an early summer campaign on a high-rise building in downtown Santiago de Chile. Distinct gradients of decreasing concentrations with altitude were observed for HONO and NOx, while O3 concentrations were found to increase with altitude. From the observed daytime maximum of the HONO/NOx ratio the existence of a strong daytime source of HONO is proposed, thus confirming recent results from another measurement site in downtown Santiago, where a high contribution of HONO to the OH radical initiation sources of >50% was observed. Since the HONO/NOx ratio and its daytime maximum were found to be independent of the altitude, it is concluded that HONO is an important OH radical source in Santiago not only close to the ground surface, but also at higher altitudes of the boundary layer. [Copyright &y& Elsevier]

Abstract: The oxidation capacity of the highly polluted urban area of Santiago de Chile has been evaluated during a winter measurement campaign from May 25 to June 07, 2005, with the results compared and contrasted with those previously evaluated during a summer campaign from March 8 to 20, 2005. The OH radical budget was evaluated in both campaigns employing a simple quasi-photostationary state model (PSS) constrained with simultaneous measurements of HONO, HCHO, O3, NO, NO2, j(O1D), j(NO2), 13 alkenes and meteorological parameters. In addition, a zero dimensional photochemical box model based on the Master Chemical Mechanism (MCMv3.1) has been used for the analysis of the radical budgets and concentrations of OH, HO2 and RO2. Besides the above parameters, the MCM model has been constrained by the measured CO and other volatile organic compounds (VOCs) including alkanes and aromatics. Total production and destruction rates of OH and HO2 in winter are about two times lower than that during summer. Simulated OH levels by both PSS and MCM models are similar during the daytime for both winter and summer indicating that the primary OH sources and sinks included in the simple PSS model are predominant. On a 24 h basis, HONO photolysis was shown to be the most important primary OH radical source comprising 81% and 52% of the OH initiation rate during winter and summer, respectively followed by alkene ozonolysis (12.5% and 29%), photolysis of HCHO (6.1% and 15%), and photolysis of O3 (<1% and 4%), respectively. During both winter and summer, there was a balance between the OH secondary production (HO2 + NO) and destruction (OH + VOCs) showing that initiation sources of RO2 and HO2 are no net OH initiation sources. This result was found to be fulfilled also for all other studies investigated. Seasonal impacts on the radical budgets are also discussed. [Copyright &y& Elsevier]

Abstract: The city of Santiago, Chile experiences frequent high pollution episodes and as a consequence very high ozone concentrations, which are associated with health problems including increasing daily mortality and hospital admissions for respiratory illnesses. The development of ozone abatement strategies requires the determination of the potential of each pollutant to produce ozone, taking into account known mechanisms and chemical kinetics in addition to ambient atmospheric conditions. In this study, the photochemical formation of ozone during a summer campaign carried out from March 8–20, 2005 has been investigated using an urban photochemical box model based on the Master Chemical Mechanism (MCMv3.1). The MCM box model has been constrained with 10 min averages of simultaneous measurements of HONO, HCHO, CO, NO, j(O1D), j(NO2), 31 volatile organic compounds (VOCs) and meteorological parameters. The O3–NOx–VOC sensitivities have been determined by simulating ozone formation at different VOC and NOx concentrations. Ozone sensitivity analyses showed that photochemical ozone formation is VOC-limited under average summertime conditions in Santiago. The results of the model simulations have been compared with a set of potential empirical indicator relationships including H2O2/HNO3, HCHO/NOy and O3/NOz. The ozone forming potential of each measured VOC has been determined using the MCM box model. The impacts of the above study on possible summertime ozone control strategies in Santiago are discussed. [Copyright &y& Elsevier]

In recent years several new genes for autosomal recessive congenital ichthyosis (ARCI) have been identified. However, little is known about the molecular epidemiology and pathophysiology of this genetically and clinically heterogeneous group of severe disorders of keratinization. ARCI is characterized by intense scaling of the whole integument often associated with erythema. We and others have shown that mutations in ALOX12B and ALOXE3, coding for the lipoxygenases 12R-LOX and eLOX-3 predominantly synthesized in the epidermis, can underlie this rare condition. Here we have surveyed a large group of 250 patients with ARCI for mutations in these two genes. We have identified 11 different previously unreported mutations in ALOX12B and ALOXE3 in 21 ARCI patients from 19 unrelated families and demonstrated that mutations in the two genes are the second most common cause for ARCI in this cohort of patients. Examination of the molecular data revealed allelic heterogeneity for ALOX12B and two mutational hotspots in ALOXE3. Functional analysis of all missense mutations and a splice site mutation demonstrated that complete loss of function of the enzymes underlies the phenotype. Our findings further establish the pivotal role of the 12-lipoxygenase pathway during epidermal differentiation.Journal of Investigative Dermatology (2009) 129, 1421–1428; doi:10.1038/jid.2008.409; published online 8 January 2009 [ABSTRACT FROM AUTHOR]

In order to quantify the contribution of solvent use and road traffic to the total non-methane volatile organic compound (NMVOC) emissions in Germany, the composition of air in the city of Wuppertal was investigated during three campaigns at different locations. The measurements covered NMVOCs in the range of C3–C10 hydrocarbons and C1–C6 oxygenated compounds. An assessment of the contribution from different emission sources to the observed NMVOC concentrations was attempted with the chemical mass balance (CMB) modelling technique. Emission profiles for traffic were obtained from measurements performed in a traffic tunnel, at a downtown street intersection and during drives through the city and on motorways. Solvent emission profiles were investigated in the vicinity of different factories and workshops using solvents in Wuppertal. Apportionment analyses were performed for several receptor points located down-wind from the city centre, in residential, dense traffic and industrial areas. The results of the present work show that traffic emission rather than solvent use determines the ambient NMVOC composition. The maximum contribution of solvent use to the NMVOC emission estimated on the basis of experimentally obtained results amounts to about 23% in the whole area of Wuppertal. It can be concluded that the contribution of solvent use to the NMVOC concentrations also in other German cities falls in the range of few to about 20%, assuming that Wuppertal can be considered as a typical German urban area with certain proportions of domestic, traffic and various industrial activities. These results are in strong disagreement with the German Emission Inventory, which states, that in the reference year 2003 about 51% of the total NMVOC emissions originate from solvent use and only 14% from traffic. [Copyright &y& Elsevier]

Polyamine (PA), one of the important plant growth regulators, is closely associated with drought stress. However, the function of conjugated PA is not still clear in the roots of cucumber seedlings under polyethylene glycol (PEG) osmotic stress. Therefore, in this study the relationship between the levels of conjugated polyamines and the activity of H+-ATPase in plasma membrane was elucidated with the roots of two cucumber (Cucumis sativus L.) cultivars, which were different in drought tolerance, as experimental materials. Furthermore, the contents of free PAs and the activities of S-adenosylmethionine decarboxylase (SAMDC) and transglutaminase (TGase), which were closely related to the levels of conjugated polyamines, were also determined. Results showed that under osmotic stress, the increases of the levels of non-covalently conjugated (non-CC) spermidine (Spd) and spermine (Spm), covalently conjugated (CC) putrescine (Put) and Spd in plasma membrane of drought-tolerant Tangshan 5 were more obvious than those of drought-sensitive Jinyou 1. Furthermore, the conjugated PAs mentioned above were closely correlated with increase rate of seedling dry weight, plasma membrane permeability, water content and H+-ATPase activity in plasma membrane. Results of the additional tests, in which exogenous Spd, Spm and two inhibitors, MGBG and phenanthrolin were used, were complementary to the results above. From these results, it could be concluded that non-CC Spd and Spm, CC Put and Spd in plasma membrane functioned in enhancing the tolerance of cucumber seedlings to osmotic stress via elevating H+-ATPase activity. Title: Polyamines conjugated to plasma membrane functioned in enhancing the tolerance of cucumber seedlings to osmotic stress via elevating H+-ATPase activity (The black arrows indicate PA contents and enzyme activities increasing, the yellow arrows indicate the results in the present research and the green arrows indicate the results that have been already elucidated or would be elucidated in the future). Osmotic stress facilitated the activities of S -adenosylmethionine decarboxylase (SAMDC) and transglutaminase (TGase) in cucumber seedling roots under osmotic stress. The increased SAMDC activity resulted in the transformation of free Put to free Spd and Spm. Subsequently, free Spd and Spm non-covalently conjugated (non-CC) to plasma membrane due to their more carried positive charges. On the other hand, the increased TGase activity catalyzed the transformation of free polyamine (PA) to conjugated covalently (CC) PA, resulting in elevating the levels of CC Put and CC Spd in plasma membrane. By elevating H+-ATPase activity, non-CC Spd, non-CC Spm, CC Put and CC Spd enhanced the tolerance of cucumber seedlings to osmotic stress, as judged by the indexes of relative increase rate of seedling dry weight, relative water content of root, relative plasma membrane permeability and MDA content. [Display omitted] • Osmotic stress increased the levels of conjugated PAs in plasma membrane. • Conjugated PAs enhanced H+-ATPase activity in plasma membrane under osmotic stress. • Conjugated PAs in plasma membrane were closely associated with the stress-tolerance. [ABSTRACT FROM AUTHOR]

Novel analogs of the allosteric, biased PAR1 ligand ML161 (parmodulin 2, PM2) were prepared in order to identify potential anti-thrombotic and anti-inflammatory compounds of the parmodulin class with improved properties. Investigations of structure-activity relationships of the western portion of the 1,3-diaminobenzene scaffold were performed using an intracellular calcium mobilization assay with endothelial cells, and several heterocycles were identified that inhibited PAR1 at sub-micromolar concentrations. The oxazole NRD-21 was profiled in additional detail, and it was confirmed to act as a selective, reversible, negative allosteric modulator of PAR1. In addition to inhibiting human platelet aggregation, it showed superior anti-inflammatory activity to ML161 in a qPCR assay measuring the expression of tissue factor in response to the cytokine TNF-alpha in endothelial cells. Additionally, NRD-21 is much more plasma stable than ML161, and is a promising lead compound for the parmodulin class for anti-thrombotic and anti-inflammatory indications. [ABSTRACT FROM AUTHOR]

Abstract Ps d2 is a pea defensin with 47 amino acid residues that inhibits the growth of fungal species by an uncharacterized mechanism. In this work, Ps d2 interactions with model membranes mimicking the lipid compositions of different organisms were evaluated. Protein-lipid overlay assays indicated that Ps d2 recognizes Fusarium solani glucosylceramide (GlcCer F.solani) and ergosterol (Erg) in addition to phosphatidylcholine (POPC) and some phosphatidylinositol species, such as PtdIns (3)P, (5)P and (3,5)P 2 , suggesting that these lipids may play important roles as Ps d2 targets. Assays using lipid vesicles were also performed to study the behaviour and dynamics that occur after peptide-membrane interactions. Surface plasmon resonance analysis showed that Ps d2 has a higher affinity for pure POPC and POPC-based vesicles containing GlcCer and Erg at a 70:30 proportion than for vesicles containing cholesterol (Chol). Partition experiments by fluorescence spectroscopy showed a decrease in Trp42 quantum yield of Ps d2 in the presence of GlcCer F.solani and Erg, individually or in simultaneously enriched membranes. The partition coefficient (K p) obtained indicated a Ps d2 partition preference for this vesicles, confirmed by quenching assays using acrylamide and 5/16-doxyl-stearic acid. Furthermore, we showed that the presence of C8 C9 double bonds and a methyl group at position C9 of the sphingoid base backbone of GlcCer was relevant to Ps d2 activity against Aspergillus nidulans. These results are consistent with the selectivity of Ps d2 against fungi and its lack of toxicity in human erythrocytes. Ps d2 represents a promising natural compound for the treatment of fungal infections. Graphical abstract Proposed model for Ps d2 interaction with fungal and mammalian membranes. Our results suggest that Ps d2 binds, possibly through the tryptophan residue, with higher affinity to membranes containing fungal glucosylceramide (GlcCer) or ergosterol or both. This interaction occurs possibly through the tryptophan residue at position 42. In contrast, Ps d2 binds with lower affinity to membranes composed of cholesterol, as mammalian cell membranes. The specific structure found in the sphingoid base of the fungal GlcCer seem relevant for Ps d2 binding, as fungal cells deficient in C9-methylation are more resistant to the peptide. Finally, the lack of hemolytic activity by Ps d2 suggests that this peptide specifically recognizes fungal-like membranes. Unlabelled Image Highlights • Ps d2 defensin interacts with mimetic membranes containing ergosterol and Fusarium solani glucosylceramide. • Ps d2 Trp42 is partially buried in the hydrophobic region of the fungal mimetic membrane as seen by quenching assays. • Ps d2 antifungal activity requires the presence of glucose in glucosylceramide and C9-methylation in the sphingoid base. • The low affinity of Ps d2 for cholesterol-containing vesicles corroborated its lack of lytic activity in erythrocytes • The described properties make Ps d2 a suitable prototype for antifungal drugs design. [ABSTRACT FROM AUTHOR]

Pannexins are membrane channel proteins that play a role in a number of critical biological processes (Panchin et al., 2000; Shestopalov, Panchin, 2008). Among other cellular functions, pannexin hemichannels serve as purine nucleoside conduits providing ATP efflux into the extracellular space (Dahl, 2015), where it is rapidly degraded to adenosine. Pannexin1 (Panx1) is abundantly expressed in the brain and has been shown to contribute to adenosine signaling in nervous system tissues (Prochnow et al., 2012). We hypothesized that pannexin1 may contribute to sleep-wake cycle regulation through extracellular adenosine, a well-established paracrine factor in slow wave sleep. To investigate this link, EEG and movement activity throughout the light/dark cycle were compared in Panx1 −/− and Panx1 +/+ mice. We found a significant increase in waking and a correspondent decrease in slow wave sleep percentages in the Panx1 −/− animals. These changes were especially pronounced during the dark period. Furthermore, we found a significant increase in movement activity of Panx1 −/− mice. These findings are consistent with the hypothesis that extracellular adenosine is relatively depleted in Panx1 −/− animals due to the absence of the ATP-permeable hemichannels. At the same time, sleep rebound after a 6-h sleep deprivation remained unchanged in Panx1 −/− mice as compared to the control animals. Behavioral tests revealed that Panx1 −/− mice were significantly faster during their descent along the vertical pole but more sluggish during their run through the horizontal pole as compared to the control mice. [ABSTRACT FROM AUTHOR]

Polyamines (PAs), one of plant growth regulators, play an important role in the plant resistance to drought stress. However, the precise function of putrescine (Put) transformation to other forms of PAs is not clear in filling maize grain embryos. In this study, two maize (Zea mays L.) cultivars, Yedan No. 13 (drought-resistant) and Xundan No. 22 (drought-sensitive), were used as experimental materials. Maize was planted in big plastic basins during whole growth period, and from the 25th day after fertilization, the plants were treated with drought (−1.0 MPa), PAs and inhibitors for 12 d. The experiments were performed during three consecutive years. The changes in the levels of three main free PAs, Put, spermidine (Spd) and spermine (Spm), covalently conjugated PAs (perchloric acid-soluble), covalently bound PAs (perchloric acid-insoluble), the activities of arginine decarboxylase, S -adenosylmethionine decarboxylase, and transglutaminase were investigated in embryos of filling grains. During drought stress, free Put increased from 109 to 367 nmol g−1 FW and from 107 to 142 nmol g−1 FW in Xundan 22 and in Yedan 13, respectively. Meanwhile, free Spd, free Spm and bound Put increased 2.7, 3.0 and 4.2 times in Yedan 13, respectively, and they merely increased about 1.5 times in Xundan 22. These results suggested that free Spd/Spm and bound Put, which were transformed from free Put, were possibly involved in drought resistance. Exogenous Spd treatment enhanced the drought-induced increase in endogenous free Spd/Spm content in drought-sensitive Xundan 22, coupled with the increase in drought resistance, as judged by the decrease in ear leaf relative plasma membrane permeability and increases in ear leaf relative water content, 1000-grain weight and grain number per ear. The suggestion was further testified with methylglyoxal-bis guanylhydrazone and o -phenanthrolin treatments. Collectively, it could be inferred that transformation of free Put to free Spd/Spm and bound Put in filling grain embryos functioned in enhancing the resistance of maize plants to soil drought. Title: Put transformation to other forms of PAs in filling grain embryos functioned in enhancing the resistance of maize plants to D.S. The black arrows mean the PA contents and enzyme activities increasing and the green arrows indicate the results in the present research.In the drought-resistant maize cultivar, Yedan No. 13, D.S. induced the increases in activities of ADC, SAMDC and TGase. By the action of ADC, free Put level increased. Then in quick succession, free Put could be effectively transformed into free Spd/Spm and bound Put by catalysis of SAMDC and TGase, respectively. Free Spd/Spm and bound Put helped in tolerance of maize plants towards D.S., as judged by the indexes of ear leaf relative water content and plasma membrane permeability, 1000-grain weight and grain number per ear. [Display omitted] • Drought stress increases free putrescine in filling grains in drought tolerant and sensitive cultivar. • Free putrescine transformation to free spermidine, spermine and bound putrescine elevates the resistance. • Free putrescine cannot be effectively transformed in sensitive cultivar under drought stress. [ABSTRACT FROM AUTHOR]

Emission factors (EFs) of pollutants emitted by light-duty vehicles (LDV) were investigated in the Leopold II tunnel in Brussels city center (Belgium), in September 2011 and in January 2013, respectively. Two sampling sites were housing the instruments for the measurements of a large range of air pollutants, including non-methane volatile organic compounds (NMVOCs), nitrogen oxides (NO x ) and carbon dioxide (CO 2 ). The NMVOCs and NO x traffic EFs for LDV were determined from their correlation with CO 2 using a single point analysis method. The emission factor of NO x is (544 ± 199) mg vehicle −1 km −1 ; NMVOCs emission factors vary from (0.26 ± 0.09) mg vehicle −1 km −1 for cis-but-2-ene to (8.11 ± 2.71) mg vehicle −1 km −1 for toluene. Good agreement is observed between the EFs determined in the Leopold II tunnel and the most recent EFs determined in another European roadway tunnel in 2004, with only a slight decrease of the EFs during the last decade. An historical perspective is provided and the observed trend in the NMVOCs emission factors reflect changes in the car fleet composition, the fuels and/or the engine technology that have occurred within the last three decades in Europe. [ABSTRACT FROM AUTHOR]

Abstract: In the present study, problems of different methods used for quantifying the air remediation activity of photo-catalytic active surfaces are described. It is demonstrated that in bed photo-reactors (e.g. ISO), transport limitations can lead to underestimation of the activity, if fast heterogeneous reactions are investigated. In contrast, in stirred tank photo-reactors (e.g. UNI), complex secondary chemistry may lead to an overestimation of the photo-catalytic remediation of NO x , if NO2 is also present. In addition, the quantities, used for ranking the photo-catalytic air remediation activity in the different methods are not independent of the applied experimental conditions, and thus, make any intercomparison between the different methods or the extrapolation to atmospheric conditions very difficult. Furthermore, unrealistic high NO x levels are used, for which the chemical kinetics may already be affected by surface saturation problems. Finally, it is shown that the use of only nitrogen monoxide (NO) will not enable users to judge about the quality and effectiveness of a photo-catalytic surface for improving air quality, since surfaces which are active toward NO may be completely non-reactive toward other important atmospheric pollutants. A modified method for quantifying the air remediation activity of photo-catalytic surfaces is proposed here to overcome these problems. [Copyright &y& Elsevier]