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Abstract A number of governance mechanisms address socio-environmental challenges associated with commodity agriculture in tropical forested countries. Governance mechanisms that prove effective in one agricultural sector are often applied to other sectors as well. For example, voluntary certification programs have been adopted by producers of commodities as diverse as beef, coffee, palm oil, and soy. However, there are substantial differences in the extent to which governance mechanisms scale up and achieve impact in different sectors. This paper analyzes how the potential for scaling up a particular governance mechanism is influenced by environmental, market, and social geographies that differ between sectors. Through stakeholder interviews, farm-level surveys, and a literature review, we examine two types of voluntary governance mechanisms (third-party certification, and sustainable intensification programs) in the coffee and cattle sectors in Brazil, to understand why the two governance mechanisms have scaled differently between these two sectors. We find that third-party certification programs have scaled up relatively well in Brazil's coffee sector, more so than its cattle sector, in part owing to differences in sustainability priorities, market orientations, supply chain traceability, and social networks between the two sectors. We also find that pilot sustainable intensification programs in the cattle sector have had more success than certification in engaging farmers, in part because they involve less investment from participating farmers. We conclude that the distribution and quality of environmental resources, markets, knowledge, actors, and networks can play an important role in the ability of a governance mechanism to effectively take root. [ABSTRACT FROM AUTHOR]

Focuses on a study that presents a technique for measuring the anisotropy energy of magneto-optical media. Importance of the behavior of perpendicular magnetic anisotropy and its origins for magneto-optical recording media; Magnetic properties of the samples studied; Anisotropy energy measurements.

Presents information on a study which proposed a method to derive the value of domain-wall energy density from the difference between the onset of expanding and collapsing fields for circular domains. Contributions to the energy formation of the domain in magneto-optical materials; Experimental procedure; Experimental results.

This paper presents a theory for the collapse of the edge zonal shear layer, as observed at the density limit at low β. This paper investigates the scaling of the transport and mean profiles with the adiabaticity parameter α, with special emphasizes on fluxes relevant to zonal flow (ZF) generation. We show that the adiabaticity parameter characterizes the strength of production of zonal flows and so determines the state of turbulence. A 1D reduced model that self-consistently describes the spatiotemporal evolution of the mean density n ¯ , the azimuthal flow v ¯ y , and the turbulent potential enstrophy ε = ⟨ ( n ̃ − ∇ 2 ϕ ̃ ) 2 / 2 ⟩ —related to fluctuation intensity—is presented. Quasi-linear analysis determines how the particle flux Γn and vorticity flux Π = − χ y ∇ 2 v y + Π r e s scale with α, in both hydrodynamic and adiabatic regimes. As the plasma response passes from adiabatic (α > 1) to hydrodynamic (α < 1), the particle flux Γn is enhanced and the turbulent viscosity χy increases. However, the residual flux Πres—which drives the flow—drops with α. As a result, the mean vorticity gradient ∇ 2 v ¯ y = Π r e s / χ y —representative of the strength of the shear—also drops. The shear layer then collapses and turbulence is enhanced. The collapse is due to a decrease in ZF production, not an increase in damping. A physical picture for the onset of collapse is presented. The findings of this paper are used to motivate an explanation of the phenomenology of low β density limit evolution. A change from adiabatic ( α = k z 2 v t h 2 / ( | ω | ν e i ) > 1 ) to hydrodynamic (α < 1) electron dynamics is associated with the density limit. [ABSTRACT FROM AUTHOR]

The results of modeling studies of an enhanced confinement in the drift wave turbulent plasma of the CSDX linear device are presented. The mechanism of enhanced confinement is investigated here using a reduced 1D, time-dependent model, which illustrates the exchange of enstrophy between two disparate scale structures: the mesoscale flow and profile, and the turbulence intensity fields. Mean density, mean vorticity, and turbulent potential enstrophy are the variables for this model. Total potential enstrophy is conserved in this model. Vorticity mixing occurs on a scale length related to an effective Rhines' scale of turbulence, and shrinks as both density and vorticity gradients steepen. Numerical results obtained from solution of the model agree well with the experimental data from CSDX showing: (i) a steepening of the mean density profile, indicating a radial transport barrier formation, (ii) the development of a radially sheared azimuthal flow velocity that coincides with the density steepening and initiates a turbulence quench, and (iii) negative Reynolds work values, indicating that fluctuations drive the shear flow. These observations as the magnitude of the magnetic field B increases are recovered using purely diffusive expressions for the vorticity and density fluxes. A new dimensionless turbulence parameter RDT-defined as the ratio of the integrated potential enstrophy transfer from turbulence to the flow, to the integrated potential enstrophy production due to relaxation of the density gradient is introduced as a turbulence collapse indicator that detects when the enhanced confinement state is triggered. [ABSTRACT FROM AUTHOR]

Discusses infrared (IR)-thermography for strain analysis in pultruded fiber reinforced plastics. Description of the uses of Thermoelastic Stress Analysis; Measurement of pultruded composites; Definition of the DeltaTherm thermoelasticity measurement system.

Presents a study on kick-starting calcium cycling in rats. Presentation of a novel approach to gene therapy for heart failure; Importance of calcium movement to the process of excitation–contraction coupling in cardiac myocytes; Use of molecular targeting to enhance calcium cycling and increase contractility in the failing heart.

This paper describes the ecology of drift wave turbulence and mean flows in the coupled drift-ion acoustic wave plasma of a CSDX linear device. A 1D reduced model that studies the spatiotemporal evolution of plasma mean density n ¯ , and mean flows v ¯ y and v ¯ z , in addition to fluctuation intensity ε, is presented. Here, ε = 〈 n ̃ 2 + ( ∇ ⊥ ϕ ̃ ) 2 + v ̃ z 2 〉 is the conserved energy field. The model uses a mixing length lmix inversely proportional to both axial and azimuthal flow shear. This form of lmix closes the loop on total energy. The model self-consistently describes variations in plasma profiles, including mean flows and turbulent stresses. It investigates the energy exchange between the fluctuation intensity and mean profiles via particle flux 〈 n ̃ v ̃ x 〉 and Reynolds stresses 〈 v ̃ x v ̃ y 〉 and 〈 v ̃ x v ̃ z 〉. Acoustic coupling breaks parallel symmetry and generates a parallel residual stress Π x z r e s . The model uses a set of equations to explain the acceleration of v ¯ y and v ¯ z via Π x y r e s ∝ ∇ n ¯ and Π x y r e s ∝ ∇ n ¯ . Flow dynamics in the parallel direction are related to those in the perpendicular direction through an empirical coupling constant σVT. This constant measures the degree of symmetry breaking in the 〈 k m k z 〉 correlator and determines the efficiency of ∇ n ¯ in driving v ¯ z . The model also establishes a relation between ∇ v ¯ y and ∇ v ¯ z , via the ratio of the stresses Π x y r e s and Π x z r e s . When parallel to perpendicular flow coupling is weak, axial Reynolds power P x z R e = − 〈 v ̃ x v ̃ z 〉 ∇ v ¯ z is less than the azimuthal Reynolds power P x y R e = − 〈 v ̃ x v ̃ y 〉 ∇ v ¯ y . The model is then reduced to a 2-field predator/prey model where v ¯ z is parasitic to the system and fluctuations evolve self-consistently. Finally, turbulent diffusion in CSDX follows the scaling: D CSDX = D B ρ ⋆ 0.6 , where DB is the Bohm diffusion coefficient and ρ ⋆ is the ion gyroradius normalized to the density gradient | ∇ n ¯ / n ¯ | − 1 . [ABSTRACT FROM AUTHOR]

Focuses on a study which determined the intrinsic perpendicular magnetic anisotropy energy constant for amorphous rare earth-transition metal terbium iron cobalt and multilayered cobalt platinum thin film samples. Information on perpendicular magnetic anisotropy energy; Techniques based on the Hall and Kerr effect; Experimental observations and results.

The article focuses on studies concerning adeno-associated vectors (AAV) and cardiovascular disease. A study conducted by C.F. McTiernan may provide some clue to new pathways controlling the delicate balance between induction of deleterious T-cell responses and operational immune tolerance to the AAV2 and payload gene proteins.

Detailed measurements of intrinsic axial flow generation parallel to the magnetic field in the controlled shear decorrelation experiment linear plasma device with no axial momentum input are presented and compared to theory. The results show a causal link from the density gradient to drift-wave turbulence with broken spectral symmetry and development of the axial mean parallel flow. As the density gradient steepens, the axial and azimuthal Reynolds stresses increase and radially sheared azimuthal and axial mean flows develop. A turbulent axial momentum balance analysis shows that the axial Reynolds stress drives the radially sheared axial mean flow. The turbulent drive (Reynolds power) for the azimuthal flow is an order of magnitude greater than that for axial flow, suggesting that the turbulence fluctuation levels are set by azimuthal flow shear regulation. The direct energy exchange between axial and azimuthal mean flows is shown to be insignificant. Therefore, the axial flow is parasitic to the turbulence-zonal flow system and is driven primarily by the axial turbulent stress generated by that system. The non-diffusive, residual part of the axial Reynolds stress is found to be proportional to the density gradient and is formed due to dynamical asymmetry in the drift-wave turbulence. [ABSTRACT FROM AUTHOR]

The Middle Eastern population is aging rapidly, and as aging is the main risk factor for cancer, the incidence and prevalence of that disease are increasing among all the populations in the region. These developments represent huge challenges to national and community-based health services. At the current state of affairs, most Middle Eastern countries require the cooperation of international agencies in order to cope with such new challenges to their health systems. The focus and emphasis in facing these changing circumstances lie in the education and training of professionals, mainly physicians and nurses, at the primary, secondary and tertiary levels of health services. It is imperative that these training initiatives include clinical practice, with priority given to the creation of multidisciplinary teams both at the cancer centers and for home-based services. [ABSTRACT FROM PUBLISHER]

The article features a discussion on heart failure. Heart failure continues to be a progressive disease with ever increasing morbidity and mortality in the Western world. Several animal models of heart failure have been used to test the therapeutic approaches. The results will allow new strategies with other novel vectors to be used to modulate various pathways in the more common forms of heart failure, providing novel therapeutic approaches for the management of heart failure patients.

ABSTRACT The use of carbon fibre-based polymeric composites in bicycle components has dramatically increased in the last few decades. This paper presents the results of fatigue and impact testing on bicycle forks that are known to have quality-related manufacturing defects. In the investigation performed, acoustic emission testing is used to monitor crack growth during fatigue loading and impact. The results show three distinct stages in composite fatigue failure related to initiation, propagation and final growth. Implications of the results on design and testing of composite bicycle components are addressed pointing to a greater need in understanding current design procedures. [ABSTRACT FROM AUTHOR]

Although progress in conventional treatments is making steady and incremental gains to reduce mortality associated with heart failure (HF), there remains a need to explore potentially new therapeutic approaches. HF induced by different etiologies such as coronary artery disease, hypertension, diabetes, infection or inflammation results generally in calcium cycling dysregulation at the myocyte level. Recent advances in understanding of the molecular basis of these calcium cycling abnormalities, together with the evolution of increasingly efficient gene transfer technology, has placed HF within the reach of gene-based therapy. Furthermore, the recent successful completion of a phase 2 trial targeting the sarcoplasmic reticulum calcium pump ushers in a new era for gene therapy for the treatment of HF. [ABSTRACT FROM AUTHOR]

Effective clinical delivery of gene therapy to the heart requires understanding and design of complex biological systems to deliver therapeutic gene expression. The development of vectors that specifically target the myocardium, in particular bioengineered recombinant viruses, has improved the efficiency of gene delivery to the heart. These tools, coupled with advances in selection and design of the genetic payload, have led to effective cardiac gene therapy in preclinical models. This technology is currently translating to the clinic with a new wave of gene therapy trials for myocardial disease. [ABSTRACT FROM AUTHOR]

Presents an abstract of the study 'Effect of Canting on the Measured Magnetic Anisotropy Constant for Magneto-Optical Recording Media,' by Te-Ho Wu, Hong Fu, R. A. Hajjar, T. Suzuki, M. Mansuripur.

This paper demonstrates the ability to determine the individual full-field components of stress, strain and displacement in finite asymmetrical engineering structures from recorded values of a single displacement component while not necessitating differentiation of the measured displacement data; a process which can be ill-conditioned and adversely influenced by data noise and quality. While the present approach of processing recorded displacements with a stress function is not new, previous cases have been restricted to symmetrical scenarios. Full-field displacements are measured here using the digital image correlation (DIC) method. As well as satisfying load equilibrium, the experimental results agree with those predicted using the finite element method (FEM). [ABSTRACT FROM AUTHOR]

Adeno-associated virus (AAV)-based vectors are promising vehicles for therapeutic gene delivery, including for the treatment for heart failure. It has been demonstrated for each of the AAV serotypes 1 through 8 that inhibition of the proteasome results in increased transduction efficiencies. For AAV9, however, the effect of proteasome inhibitors on in vivo transduction has until now not been evaluated. Here we demonstrate, in a well-established rodent heart failure model, that concurrent treatment with the proteasome inhibitor bortezomib does not enhance the efficacy of AAV9.SERCA2a to improve cardiac function as examined by echocardiography and pressure volume analysis. Western blot analysis of SERCA2a protein and reverse transcription-PCR of SERCA2a mRNA demonstrated that bortezomib had no effect on either endogenous rat SERCA2a levels nor on expression levels of human SERCA2a delivered by AAV9.SERCA2a. Similarly, the number of AAV9 genomes in heart samples was unaffected by bortezomib treatment. Interestingly, whereas transduction of HeLa cells and neonatal rat cardiomyocytes by AAV9 was stimulated by bortezomib, transduction of adult rat cardiomyocytes was inhibited. These results indicate an organ/cell-type-specific effect of proteasome inhibition on AAV9 transduction. A future detailed analysis of the underlying molecular mechanisms promises to facilitate the development of improved AAV vectors. [ABSTRACT FROM AUTHOR]

Coronary artery disease represents the leading cause of mortality in the developed world. Percutaneous coronary intervention involving stent placement remains disadvantaged by restenosis or thrombosis. Vascular gene therapy-based methods may be approached, but lack a vascular gene delivery vector. We report a safe and efficient long-term transduction of rat carotid vessels after balloon injury intervention with a translational optimized AAV2.5 vector. Compared with other known adeno-associated virus (AAV) serotypes, AAV2.5 demonstrated the highest transduction efficiency of human coronary artery vascular smooth muscle cells (VSMCs) in vitro. Local delivery of AAV2.5-driven transgenes in injured carotid arteries resulted in transduction as soon as day 2 after surgery and persisted for at least 30 days. In contrast to adenovirus 5 vector, inflammation was not detected in AAV2.5-transduced vessels. The functional effects of AAV2.5-mediated gene transfer on neointimal thickening were assessed using the sarco/endoplasmic reticulum Ca2+ ATPase isoform 2a (SERCA2a) human gene, known to inhibit VSMC proliferation. At 30 days, human SERCA2a messenger RNA was detected in transduced arteries. Morphometric analysis revealed a significant decrease in neointimal hyperplasia in AAV2.5-SERCA2a-transduced arteries: 28.36±11.30 (n=8) vs 77.96±24.60 (n=10) μm2, in AAV2.5-green fluorescent protein-infected, P<0.05. In conclusion, AAV2.5 vector can be considered as a promising safe and effective vector for vascular gene therapy. [ABSTRACT FROM AUTHOR]

Coronary restenosis, a major complication of percutaneous balloon angioplasty, results from neointimal proliferation of vascular smooth muscle cells (VSMCs). The sarco/endoplasmic reticulum calcium ATPase 2a isoform (SERCA2a), specific to contractile VSMCs, has been reported previously to be involved in the control of the Ca2+-signaling pathways governing proliferation and migration. Moreover, SERCA2a gene transfer was reported to inhibit in vitro VSMC proliferation and to prevent neointimal thickening in a rat carotid injury model. The aim of this study was to evaluate the potential therapeutic interest of SERCA2a gene transfer for prevention of in-stent restenosis using a ex vivo model of human left internal mammary artery (hIMA) intimal thickening. Left hIMAs, obtained at the time of aorto-coronary bypass surgeries, were subjected to balloon dilatation followed by infection for 30 min with adenoviruses encoding either human SERCA2 and green fluorescence protein (GFP) or control gene (β-galactosidase, β-gal) and GFP. Proliferation of subendothelial VSMCs and neointimal thickening were observed in balloon-injured hIMA maintained 14 days in organ culture under constant pressure and perfusion. SERCA2a gene transfer prevented vascular remodeling and significantly (P<0.01, n=5) reduced neointimal thickening in injured arteries (intima/media ratio was 0.07±0.01 vs 0.40±0.03 in β-gal-infected arteries). These findings could have potential implications for treatment of pathological in-stent restenosis. [ABSTRACT FROM AUTHOR]

Targeting diseased cells is a challenging issue in both pharmacological and biological therapeutics. Gene therapy is emerging as a novel approach for treating rare diseases and for illnesses for which there is no other alternative. An important limitation of gene therapy has been the off-target effects and therefore efforts have been focused on increasing the specificity of gene transfer to the targeted organ. Here, we describe a promoter containing six nuclear factor of activated T cells (NFAT) consensus sequences, which is as efficient as the cytomegalovirus (CMV) promoter to drive expression in vascular smooth muscle cells both in vitro and in vivo. In contrast to the CMV promoter it is activated in a Ca2+-dependent manner after endoplasmic reticulum depletion and allows the transgene expression only in proliferative/diseased cells. Overexpression of sarco/endoplasmic reticulum (SR/ER) Ca2+ ATPase 2a under the control of this NFAT promoter inhibits restenosis after angioplasty in rats. In conclusion, this promoter may be useful for gene therapy in vascular proliferative diseases and other diseases involving upregulation of the NFAT pathway. [ABSTRACT FROM AUTHOR]

Intrapericardial drug delivery is a promising procedure, with the ability to localize therapeutics with the heart. Gelfoam particles are nontoxic, inexpensive, nonimmunogenic and biodegradable compounds that can be used to deliver therapeutic agents. We developed a new percutaneous approach method for intrapericardial injection, puncturing the pericardial sac safely under fluoroscopy and intravascular ultrasound (IVUS) guidance. In a porcine model of myocardial infarction (MI), we deployed gelfoam particles carrying either (a) autologous mesenchymal stem cells (MSCs) or (b) an adenovirus encoding enhanced green fluorescent protein (eGFP) 48 h post-MI. The presence of MSCs and viral infection at the infarct zone was confirmed by immunoflourescence and PCR. Puncture was performed successfully in 16 animals. Using IVUS, we successfully determined the size of the pericardial space before the puncture, and safely accessed that space in setting of pericardial effusion and also adhesions induced by the MI. Intrapericardial injection of gelfoam was safe and reliable. Presence of the MSCs and eGFP expression from adenovirus in the myocardium were confirmed after delivery. Our novel percutaneous approach to deliver (stem-) cells or adenovirus was safe and efficient in this pre-clinical model. IVUS-guided delivery is a minimally invasive procedure that seems to be a promising new strategy to deliver therapeutic agents locally to the heart. [ABSTRACT FROM AUTHOR]

Abnormal excitation–contraction coupling is a key pathophysiologic component of heart failure (HF), and at a molecular level reduced expression of the sarcoplasmic reticulum (SR) Ca2+ ATPase (SERCA2a) is a major contributor. Previous studies in small animals have suggested that restoration of SERCA function is beneficial in HF. Despite this promise, the means by which this information might be translated into potential clinical application remains uncertain. Using a recently established cardiac-directed recirculating method of gene delivery, we administered adeno-associated virus 2 (AAV2)/1SERCA2a to sheep with pacing-induced HF. We explored the effects of differing doses of AAV2/1SERCA2a (low 1 × 1010 d.r.p.; medium 1 × 1012 d.r.p. and high 1 × 1013 d.r.p.) in conjunction with an intra-coronary delivery group (2.5 × 1013 d.r.p.). At the end of the study, haemodynamic, echocardiographic, histopathologic and molecular biologic assessments were performed. Cardiac recirculation delivery of AAV2/1SERCA2a elicited a dose-dependent improvement in cardiac performance determined by left ventricular pressure analysis, (+d P/d tmax; low dose −220±70, P>0.05; medium dose 125±53, P<0.05; high dose 287±104, P<0.05) and echocardiographically (fractional shortening: low dose −3±2, P>0.05; medium dose 1±2, P>0.05; high dose 6.5±3.9, P<0.05). In addition to favourable haemodynamic effects, brain natriuretic peptide expression was reduced consistent with reversal of the HF molecular phenotype. In contrast, direct intra-coronary infusion did not elicit any effect on ventricular function. As such, AAV2/1SERCA2a elicits favourable functional and molecular actions when delivered in a mechanically targeted manner in an experimental model of HF. These observations lay a platform for potential clinical translation.Gene Therapy (2008) 15, 1550–1557; doi:10.1038/gt.2008.120; published online 24 July 2008 [ABSTRACT FROM AUTHOR]

Recombinant adeno-associated (AAV) viruses have unique properties, which make them ideal vectors for gene transfer targeting the myocardium. Numerous serotypes of AAV have been identified with variable tropisms towards cardiac tissue. In the present study, we investigated the time course of expression of eight different AAV serotypes in rat myocardium and the nature of the immunity against these serotypes. We first assessed whether neutralizing antibodies (NAb) were present for any of the serotype in the rats. We injected 100 μl of each AAV 1–8 serotype (1012 DNAse resistant particles/ml), encoding LacZ gene, into the apical wall of rat myocardium. At 1, 4, 12 and 24 weeks after gene delivery, the animals were killed and β-galactosidase (β-gal) activity was assessed by luminometry. Additionally, LacZ genomic copies and AAV capsids copies were measured through standard polymerase chain reaction analysis and cryo-sections from the area of viral injection were stained for X-gal detection at the same time points. No NAbs were detected against any of AAV serotypes. At all the time points studied, AAV1, 6 and 8 demonstrated the highest efficiency in transducing rat hearts in vivo. Parallel to the results with β-gal activity, the highest levels LacZ and AAV DNA genomic copies were with AAV1, 6 and 8. The positive X-gal staining depicted by these serotypes confirmed these results. These results indicate that among the various AAV serotypes, AAV1, 6 and 8 have differential tropism for the heart unaffected by pre-existing NAb in the rat. Although AAV 1 and 6 vectors induced rapid and robust expression and reach a plateau at 4 weeks, AAV 8 continued increasing until the end of the study. AAV 2, 5 and 7 vectors were slower to induce expression of the reporter gene, but did reach levels of expression comparable to AAV1 and AAV6 vectors after 3 months.Gene Therapy (2007) 14, 989–997. doi:10.1038/sj.gt.3302895; published online 25 January 2007 [ABSTRACT FROM AUTHOR]

Gelatin hydrogel microspheres (GHMs) have been reported as novel non-viral vectors for gene or protein delivery (GHM therapy). However, the components of an effective catheter-based delivery strategy for GHM therapy are unknown. We evaluated the effectiveness of three catheter-based strategies for cardiac GHM therapy: (1) antegrade injection (AI) via coronary arteries; (2) retrograde injection (RI) via coronary veins; and (3) direct myocardial injection (DI) via the coronary sinus. AI distributed microspheres homogeneously throughout the target area with 73±11% retention. RI scattered microspheres non-homogenously with 22±8% retention. DI distributed microspheres in the needle-advanced area with 47±14% retention. However, despite high efficiency, AI did not show biological effects of inducing angiogenesis from basic fibroblast growth factor bound to GHMs. Furthermore, focal micro-infarctions, owing to micro-embolism of aggregated GHMs into small coronary arterioles, were detected in the AI group. Conversely, only RI and DI groups displayed increased coronary flow reserve. DI groups also demonstrated increased capillary density. These results suggest that RI and DI are effective for cardiac GHM therapy, while AI appears inappropriate owing to the risk of focal infarctions.Gene Therapy (2006) 13, 1320–1327. doi:10.1038/sj.gt.3302793; published online 18 May 2006 [ABSTRACT FROM AUTHOR]

This study traces the emergence of sheared axial flow from collisional drift-wave turbulence with broken symmetry in a linear plasma device--the controlled shear decorrelation experiment. As the density profile steepens, the axial Reynolds stress develops and drives a radially sheared axial flow that is parallel to the magnetic field. Results show that the nondiffusive piece of the Reynolds stress is driven by the density gradient, results from spectral asymmetry of the turbulence, and, thus, is dynamical in origin. Taken together, these findings constitute the first simultaneous demonstration of the causal link between the density gradient, turbulence, and stress with broken spectral symmetry and the mean axial flow. [ABSTRACT FROM AUTHOR]

A correction to the article "Efficiency of eight different AAV serotypes in transducing rat myocardium in vivo" that was published in an earlier issue is presented.