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The GORE Excluder stent-graft is one of the currently available devices approved by the US Food and Drug Administration for use in endovascular aortic repair. Recently, a new delivery system modification has been applied to the Excluder device which allows repositioning of the stent-graft to adjust for accurate proximal landing and facilitate gate cannulation. In this review, we examine the Excluder device with the new C3 delivery system and its potential benefit in the management of abdominal aortic aneurysms. [ABSTRACT FROM AUTHOR]

This study uses mesoscale ensemble forecasts to compare the magnitude of nonaerosol effects of the Saharan air layer (SAL) with other environmental influences on the intensity of Tropical Storm Debby. Debby was a weak Cape Verde storm that dissipated over the tropical North Atlantic a few days after forming in August 2006. The system has received considerable attention because of its vicinity to the SAL as it struggled to intensify, which has led to speculation that the SAL helped lead to the storm's demise. Statistical correlation is used to better understand why some ensemble members strengthen the pre-Debby wave into a hurricane and others develop only a weak vortex. Although the results here suggest that the SAL slowed intensification during the predepression to depression stages, it was not likely responsible for Debby's dissipation. The most obvious SAL-related factor to affect long-term intensity in the ensembles is dry air above 2 km, which delays organization of the low-level vortex. Warm temperatures within the SAL and shear associated with the African easterly jet (AEJ) exhibit a weak, secondary relationship with forecast intensity variability. An important result here is that sensitivity to the dry environmental air depends considerably on cyclone strength, and it becomes insignificant once a tropical storm forms. Furthermore, Debby's most rapid period of intensification coincided with its track over somewhat higher sea surface temperatures, and intensification ended when the storm moved over cooler waters. The results herein suggest that this factor might have affected the storm's intensity more strongly than did any effect of the SAL. Even later, subsequent to the period examined by these ensembles, Debby dissipated under the influence of stronger vertical wind shear from an upper-level trough. These results show that the relationship among the SAL, AEJ, and developing tropical cyclones is not as straightforward as has been hypothesized by some recent studies. Ultimately, the nuanced relationship between storm intensity and the SAL shows that much care needs to be taken before drawing conclusions about the effect of the SAL on any particular cyclone. The authors therefore advocate more rigorous future analysis through both idealized and ensemble studies to more fully quantify the effect of the SAL on tropical cyclones in general. [ABSTRACT FROM AUTHOR]

Abstract: Heat and moisture transfers in the building envelope play a significant role in the energetic performances of a construction. In the present study, the dynamic behavior of a multi-composite wooden panel, including an air layer, is considered through heat and mass transport calculations. To address this problem, a vertical channel filled with humid air between hygroscopic walls was considered. Balance equations for mass, momentum, energy and vapor are solved taking into account conduction, convection, radiation, diffusion and condensation mechanisms. The transient evolutions of temperature, heat fluxes and humidity were observed versus several climatic parameters through a set of different boundary conditions. Realistic hygroscopic material and humid air properties varying with temperature and vapor mass fraction were also taken into account. [Copyright &y& Elsevier]

The potential to propagate Uapaca kirkiana through air layering was investigated at Igumbilo forest, Tanzania. The objective was to determine the effect of time of setting air layers and use of indole-3-butyric acid (IBA) to promote rooting. Air layers were initiated on young shoots, 1-to 2-years old, growing on mature trees. After root initiation, they were detached, potted and reared at the nursery for a further three months. Thereafter they were harvested and assessed. Two factors were investigated: effect of time at which air layers were initiated (June, September and December), and influence of IBA at 50, 100 and 150 mg l−1concentrations. Varied rooting successes were realised, being influenced by time at which air layers were initiated, IBA concentration or both. Optimal rooting of 82.5% was realised in June-initiated air layers treated with 50 mg l−1 IBA. Air layers initiated in December and treated with the control had the poorest rooting (46.7%). Application of 100 mg l−1 IBA during June significantly improved the number of roots, root length and root biomass produced. The increase in rooting ability during June is partly linked to better nutritive status, since most plants at this time have sufficient food reserves acquired during the active photosynthetic rainy period of January–May. The period is also associated with minimal plant developmental activities such as budding and flushing, which are usually antagonistic to rooting. Thus, air layering is a potential technique to propagate U. kirkiana, and can contribute effectively to capture desirable traits rapidly disappearing because of ongoing deforestation and maintain the desired fruit tree attributes once attained. Further studies are recommended to determine its cost effectiveness in relation to other vegetative techniques. [ABSTRACT FROM AUTHOR]

Most of fruit species are propagated by vegetative methods such as budding, grating, cutting, suckering, layering etc. to avoid heterozygocity. Carob trees (Ceratonia siliqua L.) are of highly economical value and are among the most diicult to propagate fruit species. In the study, air-layering propagation method was investigated first time to compare wild and cultivated ('Sisam') carob types. In the experiment, one year old carob limbs were air-layered on coco peat medium by wrapping with aluminum foil and polyethylene film. Initial roots were observed after three months of treatment and the well rooted limbs were cut-of after six months of treatment. Root length, diameter, and the number of roots were recorded on treated shoots and the rooted shoots were transferred into soil. As a result, it has been found that air-layering is successful in carob. his method is more labor intensive and thus it is recommend the method only for genetically important carob types propagation. [ABSTRACT FROM AUTHOR]

Abstract: Sustaining an air layer on superhydrophobic surface is known necessary for the applications of the “air layer effect” underwater on basis of previous literatures. However, the air layer becomes unstable when put underwater and even disappears when the hydraulic pressure increases. Thus much attention has been focused on the sustainability of an air layer on a superhydrophobic surface. This article studies the sustainability of the air layer on the surface of a lotus leaf by applying external pressure on the surface, which is a direct method to measure the sustainability of the air layer. It is displayed that the hydraulic pressure is a key factor to sustain an air layer on a superhydrophobic surface. Maintaining a certain amount of hydraulic pressure is necessary to sustain an air layer on a superhydrophobic surface, which may be important for the low drag or friction reduction of a superhydrophobic surface underwater. Therefore, we believe that the micro-designs of superhydrophobic surface which is capable of the “air layer effect” underwater should be connected with hydraulic pressure applied on it. [Copyright &y& Elsevier]

Abstract: The response of the field layer vegetation to co-varying resource availability (soil nutrients, light) and resource loss (herbivory pressure) was investigated along a landscape gradient highly influenced by elephants and smaller ungulates at the Chobe River front in Botswana. TWINSPAN classification was used to identify plant communities. Detrended Correspondence Analysis (DCA) and Canonical Correspondence Analysis (CCA) were used to explore the vegetation–environment relationships. Four plant communities were described: Panicum maximum woodland, Tribulus terrestris woodland/shrubland, Chloris virgata shrubland and Cynodon dactylon floodplain. Plant height, species richness and diversity decreased with increasing resource availability and resource loss. The species composition was mainly explained by differences in soil resources, followed by variables related to light availability (woody cover) and herbivory, and by interactions between these variables. The vegetation structure and species richness, on the other hand, followed the general theories of vegetation responses to herbivory more closely than resource related theories. The results suggest a strong interaction between resource availability and herbivory in their influence on the composition, species richness and structure of the plant communities. [ABSTRACT FROM AUTHOR]

Abstract: Nitrogen (N) content in the soil and in the herbaceous biomass were monitored during spring of 2004–2006 to determine how the herbaceous layer development influences soil N availability in the montado ecosystem of southern Portugal. Highest (246.6 ± 52.7 g m−2) and lowest (123.2 ± 89.5 g m−2) peak biomass occurred in 2006 and 2005 respectively. Total soil N within the top 20 cm soil profile ranged between 0.2 ± 0.1% in February and 0.41 ± 0.2% in May, while available soil N was lowest (5 ± 2 μg g−1soil) in February but increased three-to-five fold in March and was >17.5 μg g−1soil at senescence in May. Significant (p < 0.001) increase in total N in the aboveground pool occurred between February and May. There was however, no decay in soil N content. Instead, the herbaceous vegetation enhanced soil N input and N retention in the ecosystem. Most of the herbaceous plants were annuals with large reserves of organic N at senescence, which returned to the soil as detritus. The herbaceous vegetation is a critical component of the montado that contributes to N recharge and cycling within the ecosystem. [ABSTRACT FROM AUTHOR]

In this article, the author discusses the influences of the Saharan air layer (SAL) in the Global Earth Observing System (GEOS-5) global model. The author states that the SAL air goes through a cyclonic circulation which results in the prevention of a tropical cyclone. He mentions that cooler temperatures at low levels below warm, dry air can be attributed to the decrease in solar heating related to dusty air in the layer above. Moreover, the SAL cannot be directly linked to warm and dry air.

The boreal forest of higher latitudes constitutes a reservoir of trees of great ecological importance and unknown economic potential, but the stand dynamics in these regions still remain essentially unexplored. This paper examines the change in age and size structures during stand development on the northern border of the natural closed boreal forest in Quebec, Canada. Height, diameter, and age of trees were measured in 18 plots with stand ages between 77 and 340 years. The occurrence, size, and origin (layer or seed) of seedlings and saplings were assessed in subplots. Tree density ranged from 600 to 3750 trees·ha–1. Picea mariana (Mill.) BSP was the dominant species, mainly originating by layering. A cluster analysis segregated plots into even-aged and uneven-aged stands according to tree age, but size distribution of trees, saplings, and seedlings did not differ statistically between the two groups. Even-aged stands exhibited a 60% probability of assuming an uneven-aged structure between 120 and 200 years after stand initiation. At high latitudes, the closed boreal forest of P. mariana appears homogeneously sized, with similar distributions of diameter and height across all stages of stand development. [ABSTRACT FROM AUTHOR]

In this study, the role of the Saharan air layer (SAL) is investigated in the development and intensification of tropical cyclones (TCs) via modifying environmental stability and moisture, using multisensor satellite data, long-term TC track and intensity records, dust data, and numerical simulations with a state-of-the-art Weather Research and Forecasting model (WRF). The long-term relationship between dust and Atlantic TC activity shows that dust aerosols are negatively associated with hurricane activity in the Atlantic basin, especially with the major hurricanes in the western Atlantic region. Numerical simulations with the WRF for specific cases during the NASA African Monsoon Multidisciplinary Analyses (NAMMA) experiment show that, when vertical temperature and humidity profiles from the Atmospheric Infrared Sounder (AIRS) were assimilated into the model, detailed features of the warm and dry SAL, including the entrainment of dry air wrapping around the developing vortex, are well simulated. Active tropical disturbances are found along the southern edge of the SAL. The simulations show an example where the dry and warm air of the SAL intruded into the core of a developing cyclone, suppressing convection and causing a spin down of the vortical circulation. The cyclone eventually weakened. To separate the contributions from the warm temperature and dry air associated with the SAL, two additional simulations were performed, one assimilating only AIRS temperature information (AIRST) and one assimilating only AIRS humidity information (AIRSH) while keeping all other conditions the same. The AIRST experiments show almost the same simulations as the full AIRS assimilation experiments, whereas the AIRSH is close to the non-AIRS simulation. This is likely due to the thermal structure of the SAL leading to low-level temperature inversion and increased stability and vertical wind shear. These analyses suggest that dry air entrainment and the enhanced vertical wind shear may play the direct roles in leading to the TC suppression. On the other hand, the warm SAL temperature may play the indirect effects by enhancing vertical wind shear; increasing evaporative cooling; and initiating mesoscale downdrafts, which bring dry air from the upper troposphere to the lower levels. [ABSTRACT FROM AUTHOR]

Many studies have commented on the presence of midtroposphere dry air layers in normally moist areas of the warm-pool region in the tropical western Pacific Ocean. In this study, 5 yr of relative humidity (RH) observations from the Atmospheric Infrared Sounder (AIRS) instrument aboard the Aqua satellite are analyzed to identify areas of anomalously dry air between 600 and 400 hPa over deep convective regions of the tropical oceans. A dry air layer is defined when midlevel RH is <20%, accounting for the lowest 10% of RH observations. Dry air layers appear to be more frequent over the Indian and Pacific Oceans than over the Atlantic Ocean. Large seasonal differences in the locations of dry air layers are apparent in each ocean basin. Large variations are also noted across the Pacific, suggesting limits on the applicability of case-study trends and observations of dry air layers to the Pacific as a whole. Back trajectories are then calculated for each observed parcel. The origin, or location of dehydration, is identified as the point along each trajectory at which the RH of the parcel is ≥100%. An analysis of the time between dehydration and dry air observation by AIRS suggests that dry air layers in June–August tend to last 1–2 days longer than those observed in other seasons. Although more dry air layers are observed to come from each hemisphere in its respective winter, most sources of dry air layers are subtropical and contribute anomalously dry air year-round. Other meteorological features are noted in the back trajectories, such as the eastward/westward wind transition from the subtropics to the tropics and the effects of the Indian monsoon on dry air distribution paths. [ABSTRACT FROM AUTHOR]

Recently, polymer/polymer composite insulating systems have been widely used in high-voltage equipment and power cables. Such composite insulating systems always have an interface between two polymeric insulating materials. This interface may cause partial discharge and electrical treeing under high electric stresses. The electrical properties of this polymer/polymer interface have not yet been fully understood. It has been shown that the propagation characteristics of electrical trees in polymer/polymer composite insulating materials considerably vary depending on the combination of polymers. It has also been shown that a cavity or a thin gas layer generates near the polymer barrier molded in the base polymer, by the pressure of decomposing gas occurring in the tree channels during AC tree extension. In this study, we will investigate the three-dimensional simulated tree utilizing a three-layer model considering a thin gas layer on a barrier based on a DBM model with growth probability. The results show that the critical fields of air layer are related to the easiness of tree propagation in the air layer. Moreover, it is suggested that the three-layer model is more effective than the two-layer model when the tree propagation is discussed in detail. © 2009 Wiley Periodicals, Inc. Electr Eng Jpn, 168(3): 1–9, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20808 [ABSTRACT FROM AUTHOR]

The author offers insights relative to the propagation of clonal oak through grafting. He mentions the clonal propagation technique called layering which was developed by Georges Hawver and Nina Bassuk at Cornell University. The author asserts that grafting should be used in propagating clonal oaks if all other means are cumbersome and difficult. Moreover, the author emphasizes that grafting is suitable in maintaining certain qualities of oaks such as leaf color, habit, and fall color and habit.

Effects of age and conservation of the IBA hormone and their relation to procedures of performing airlayers on quality of 4" and 6" Dracaena marginata roots were evaluated using a 4×3 factorial design. The factors were human labor and conservation of hormone. Logistic regression was used to predict probability of long roots, probability of single circumference of roots and exportability. interactions between the effect of human labor and the effect of hormone levels on these three responses, can increase the cost up to 240% and suggest quality and exportability can increase if procedures are standardized. [ABSTRACT FROM AUTHOR]

Walnut (Juglans regia L.).is an important nut crop with a "difficult-to-root" characteristic. In this study, the rooting ability of. low-vigour and precocious seedlings of 3-year-old Persian walnut was compared with semi-vigorous and high-vigour seedlings using the stool layering method. The results indicated that low-vigour seedlings rooted more (40%) than semi-vigorous (31.42%) and high-vigour (17.14%) seedlings. The average number of roots per shoot (layer) and rooting score (on a scale of 1 - 5) in the low-vigour group were 7.83 and 4.19, respectively, which differed significantly from the high-vigour group. Moreover, most of the high quality adventitious roots formed on low-vigour seedlings appeared to originate from internal tissues compared to the low quality and brittle roots that originated from callus in high-vigour seedlings. Improved rooting of low-vigour seedlings, together with a significant negative correlation between layer size and root number (r = -0.29), reflects substantial structural or hormonal differences among seedlings of different vigour. Approx. 70% of rooted layers survived after transferring to field condition. Our results provide more support for the possibility of vegetative propagation of walnut by conventional stool layering, as well as the selection of easy-to-root, dwarf walnut cultivars or rootstocks on their own roots. [ABSTRACT FROM AUTHOR]

Objectives: Almost a third of patients who undergo peripheral bypass procedures do not have suitable veins, making the use of prosthetic materials necessary. Prosthetic materials can cause platelet adhesion and activation of the coagulation cascade on the graft. One potential strategy to reduce this thrombogenicity is to covalently bind heparin to the endoluminal surface of grafts. This human in vivo study examined systemic effects of the endoluminal heparin and addressed whether graft implantation results in (1) a measurable reduction of systemic markers of hemostasis activation compared with control grafts and (2) antibody formation against heparin, potentially responsible for heparin-induced thrombocytopenia (HIT). Methods: The study included 20 patients undergoing femoropopliteal bypass grafting, of whom 10 received a standard Gore-Tex Thin Walled Stretch Vascular Graft (W. L. Gore & Associates, Flagstaff, Ariz) and 10 received a heparin-bonded expanded polytetrafluoroethylene (ePTFE) graft (Gore-Tex Propaten Vascular Graft). Blood samples were drawn before and directly after the operation and at days 1, 3, 5, and week 6 after surgery. Established markers of in vivo activation of platelets and blood coagulation (prothrombin fragment 1+2, fibrinopeptide A, soluble glycoprotein V, thrombin-antithrombin complexes, and D-dimers) were measured using standard commercially available techniques. Antiplatelet factor 4/heparin antibody titers were measured using a commercially available enzyme-linked immunosorbent assay, and platelet counts were determined. Results: No statistical differences were observed in any of the markers of in vivo activation of platelets and blood coagulation between patients receiving Propaten or control ePTFE. Moreover, no antibodies against heparin could be demonstrated up to 6 weeks after implantation. Conclusions: No measurable effect of heparin immobilization on systemic markers of hemostasis was found using a heparin-bonded ePTFE graft in vivo. Also, no antibodies against heparin could be detected up to 6 weeks after implantation. [Copyright &y& Elsevier]

Mobile thrombus of the thoracic aorta is an uncommon pathology with potentially catastrophic complications. Recurrent spontaneous distal embolization may also occur from an ulcerated thrombus of the abdominal aorta. The simultaneous presence of a mobile thrombus in the thoracic aorta and ulcerated thrombus of the abdominal aorta is extremely rare and poses a significant treatment dilemma. Although various approaches have been reported, there is no standard treatment. Direct replacement of the thoracoabdominal aorta is extremely morbid, while continued embolization despite anticoagulation mandate intervention. We herein present the first case report of successful treatment of symptomatic mobile/ulcerated thrombi of the thoracic and abdominal aorta using staged endovascular stent graft repair. Successful treatment of the thoracic component with a thoracic aortic graft (TAG, Gore-Tex, W. L. Gore & Assoc., Flagstaff, Ariz.) was followed one week later by exclusion of the infrarenal aortic lesion with a bifurcated stent graft. Endovascular stent graft exclusion of mobile/ulcerated thoracic and abdominal aortic thrombi is a minimal invasive operation. It can be employed as an alternative procedure in treatment of aortic thrombus with embolization in high risk patients. Long-term follow-up will be necessary to assess the durability of this technique. [Copyright &y& Elsevier]

We previously reported that monodisperse silica particles (SiPs) afforded with a high-density brush of poly(methyl methacrylate) (PMMA) and suspended in a good solvent for PMMA formed a colloidal crystal in a certain concentration range (Macromolecules2006, 39, 1245). Here we investigated similar hybrid particles with respect to the influence of graft chain length Lcon their hydrodynamic diameter Dhin dilute suspension and on colloidal crystallization in more concentrated suspension. The average radius r0of SiPs was 65 nm, and the surface density 0of PMMA grafts at the SiP surface was about 0.7 chains/nm2(about 36 000 chains per particle). The hydrodynamic thickness of the swollen brush layer h(Dh/2 − r0) was qualitatively interpretable by a modified Daoud−Cotton-type scaling model. Namely, for short graft chains, hobeyed the universal relation, h1 (h/2r0) ∼ Lc012, applicable to concentrated polymer brusheson flat as well as spherical surfaces, and for chains longer than a critical length, hshowed positive deviations from this linear relation, indicating the brush layer getting into the semidilute polymer brushregime. Suspensions of the hybrid particles showed a phase transition from a (disordered) fluid to a fully crystallized system with a narrow fluid/crystal coexisting regime. The critical concentration of crystallization (melting point) decreased with increasing graft chain length, and the nearest-neighbor interparticle distance Ddisin the crystal approached to a micrometer scale as the graft molecular weight reached 500 000. Good correlation was observed between Dhand Ddissuch that Ddis(1.15 ± 0.05)Dh. Confocal laser scanning microscopic observation suggested that the colloidal crystal generally include both hexagonal close-packed (hcp) and face-centered cubic (fcc) lattice arrangements with the fcc arrangement likely to increase with increasing chain length. [ABSTRACT FROM AUTHOR]

Abstract: This study concerns the investigation of the effect of reaction conditions on the radiation-induced grafting of styrene into poly(ethylene-alt-tetrafluoroethylene) base film. Grafting was obtained by the pre-irradiation method, using styrene in isopropanol/water mixture. The influence of irradiation and reaction conditions, such as irradiation dose, monomer concentration, water content of the grafting solution and reaction temperature on the grafting yield was investigated. The grafting kinetics in terms of initial polymerization rate (r p0), radical recombination rate (γ) and delay time (t 0) was evaluated. It was found that the rate and the extent of grafting were strongly dependent on the grafting conditions. The order of dependence of the rate of grafting was found to be 0.46, 1.5 and 0.62 for pre-irradiation dose, monomer concentration and water content in the grafting mixture, respectively. The activation energy was determined to be 98.4kJ/mol for the temperature range of 50–80°C. The use of kinetic equations for the polymerization gives a useful description of the grafting process. It was determined that the initial polymerization rate and the radical recombination rate vary significantly with reaction conditions. The delay time is dependent mainly on irradiation dose and to some extent on monomer concentration. [Copyright &y& Elsevier]

Abstract: Binary graft copolymerization of pH sensitive acrylic acid (AAc) and thermosensitive N-isopropylacrylamide (NIPAAm) monomers onto pre-irradiated polypropylene films (PP) was carried out by two individual steps using a Co60 gamma radiation source. The influence of preparation conditions, such as pre-irradiation dose and reaction time on grafting yield was studied. The swelling behavior and FTIR-ATR study for PP films grafted films were investigated. [Copyright &y& Elsevier]

The article summarizes results from full-scale and wind-tunnel studies. It also discusses the complexity of urban canopy layer (UCL) flow and related challenges for urban modeling. In details, the wind-tunnel data for idealized street-canyon intersections demonstrate that street-level flow and dispersion patterns are significantly altered for configurations with non-uniform building heights. Detailed information regarding the methods and analysis used in the studies, as well as the results, is elaborated.

Objective: The invention of robotic systems has begun a new era of endoscopic cardiac surgery. Reports on totally endoscopic coronary artery bypass grafting are limited, however, and data regarding feasibility, safety, and efficacy are needed to determine this technique’s position in the therapeutic armamentarium. This study describes the largest multicenter experience in the literature with robotic totally endoscopic coronary artery bypass grafting specifically addressing procedural feasibility, safety, and efficacy. Methods: Between September 1998 and November 2002, a total of 228 patients with coronary artery disease were scheduled for totally endoscopic coronary artery bypass grafting with the da Vinci Surgical System (Intuitive Surgical Inc, Sunnyvale, Calif.) at five European institutions. Patients underwent totally endoscopic coronary artery bypass grafting with either an on-pump (group A, n = 117) or an off-pump approach (group B, n = 111). Patients underwent postoperative angiography or stress electrocardiography and were followed up for 6 months. Results: Procedural feasibility was demonstrated through the completion of 164 successful totally endoscopic cases. Sixty-four patients (group C, 28%) had conversion to nonrobotic procedures. Conversion rates decreased with time. The overall procedural efficacy, as defined by angiographic patency or lack of ischemic signs on stress electrocardiography, was 97%. The incidence of major adverse cardiac events within 6 months was 5%. Conclusion: Both on- and off-pump totally endoscopic coronary artery bypass grafting are feasible, with a conversion rate that diminishes with increasing experience. Conversion does not adversely affect outcome and thus constitutes a safe alternative. Although target vessel reintervention may be slightly higher than that reported for open coronary artery bypass grafting, graft patency and major adverse cardiac events for both approaches are comparable to those reported in the Society of Thoracic Surgeons database, demonstrating the safety and efficacy of the totally endoscopic coronary artery bypass grafting procedure. [Copyright &y& Elsevier]

Objective: After single lung transplantation for emphysema, the volume of the graft at total lung capacity is usually less than its predicted volume in the donor. We sought to determine the contributions of donor–recipient size matching, postoperative native lung hyperinflation, and postoperative chest wall volume reduction to graft restriction after transplantation. Methods: In 19 patients, we estimated individual lung volumes from thoracic computed tomographs taken near total lung capacity before and after single lung transplantation for emphysema to analyze sources of graft restriction. Pulmonary function was assessed by spirometry, and in 5 patients, inspiratory function was assessed with esophageal manometry. Results: Graft volumes after transplantation were 54% ± 17% of those predicted for the donors (mean ± SD, P < .0001), and pulmonary function after transplantation was significantly correlated with graft volume. The greatest contribution to graft restriction was the decrease in chest wall volume after transplantation, which was −0.87 L (−31% ± 29% of the graft’s predicted volume; P < .0001). Volume expansion of the contralateral lung contributed −0.44 L (−18% ± 24%; P = .0018). Other effects, including donor–patient size matching, were not significant. In 5 patients, the maximum negative inspiratory esophageal pressure at total lung capacity was low (−6 ± 2 cm H2O, normal range ∼−17 to −29 cm H2O). Conclusions: After single lung transplantation for emphysema, decreased volume of the chest wall was more important than increased volume of the native lung in causing restriction of the graft and decreased pulmonary function. Chest wall restriction is likely due to diminished inspiratory muscle function. [Copyright &y& Elsevier]

Background: Coronary artery bypass grafting with concomitant coronary endarterectomy (CABG/CE) is used in patients with severe coronary atherosclerosis to revascularize otherwise ungraftable targets. This study investigates the efficacy of arterial versus vein grafting for CABG/CE surgery. Methods: We reviewed our experience in 288 CABG/CE patients (63 ± 10 years, 207 men). A total of 1,056 grafts (275 internal thoracic artery [ITA] [26%]; 221 radial [21%], 560 vein [53%]) were constructed including 325 (31%) placed to CE targets. Results: Eighteen of 288 patients died in-hospital (6.3%). Unadjusted one-year and five-year survival for the 270 discharged patients was 95.2% and 83.0%, respectively. Survival (0 to 7 years) was significantly better for patients with radial (n = 154) versus no-radial (n = 134) artery grafting (p = 0.021). Multivariate Cox regression analysis associated increased number of arterial grafts (hazard ratio [HR] = 0.64 [0.44 to 0.92]; HR [95% confidence interval]) to improved survival, while RCA endarterectomy (HR = 1.8 1.0 3.3; p = 0.054) was associated with worse survival. Repeat angiography (495 days [median]) in 68 patients encompassed 78 CE (38 vein, 24 ITA, and 16 radial) and 162 non-CE (84 vein, 40 ITA, and 38 radial) grafts. Graft failure was similar (p = 0.37) for radial (10 of 54 [19%]) and ITA (7 of 64 [11%]), and worst for vein (50 of 122 [41%]; p < 0.001). For CE targets, graft failure was worse for vein (55% vs 35%; p = 0.05) and unchanged for arterial (13% vs 15%; p = 0.88) grafts. Conclusions: Combined CABG/CE is associated with good long-term outcomes. Increased arterial grafting achieved by radial artery utilization confers a survival benefit in this high-risk population. The latter is probably derived from superior radial versus vein graft patency. [Copyright &y& Elsevier]

Purpose: We have recently reported that application of carbodiimide-derivatized hyaluronic acid and gelatin (cd-HA gelatin) to a peroneus longus tendon graft increased tendon graft gliding ability and decreased work of flexion compared with untreated grafts in a canine model in vivo. In this study, we investigated the effect of this modification on adhesions, stiffness, strength of the distal attachment, and fibroblast count. Methods: A total of 24 dogs were used for this study. The peroneus longus tendons of each hind leg were grafted into the 2nd and 5th digits of one forepaw in each dog. One peroneus longus tendon was treated with cd-HA gelatin prior to grafting, and the other one was immersed in 0.9% saline solution as a control. Animals were killed 1, 3, or 6 weeks postoperatively. Results: The adhesion score of cd-HA gelatin–treated tendons was significantly less than that in the saline-treated tendons at all time points. There was no significant difference in the indentation stiffness between HA- and saline-treated grafts at any time point. For the ultimate force at the distal attachment, there was a significant difference among the time points, with a steady increase over time, but no significant difference between treated and control tendons at any time point. There was no significant difference in fibroblast count between treated and control tendons at any time point. Conclusions: Although gross adhesion formation was less, there was no significant difference in strength at the distal tendon-bone interface, cellularity, or tendon graft stiffness when comparing saline-treated and cd-HA gelatin–treated tendon grafts in vivo. [Copyright &y& Elsevier]

Background: β-adrenoceptor antagonist celiprolol has been widely used as an effective antihypertensive agent. Some studies reported that celiprolol enhances nitric oxide production. The purpose of the present study is to examine the effects of celiprolol on vein graft intimal hyperplasia and endothelium-dependent nitric oxide (NO)-mediated relaxation. Methods: Japanese white rabbits were randomized to a control group that was fed regular rabbit chow or to a celiprolol group that was fed regular rabbit chow supplemented with 100 mg/body celiprolol sodium. The reversed jugular vein was implanted into the carotid artery. At 2 and 4 weeks after the operation, vein grafts in both groups were harvested, and intimal hyperplasia of the vein grafts was assessed. At 4 weeks after the operation, harvested vein grafts from both the groups were examined on the endothelium-dependent relaxation by application of Ach and were examined to detect for endothelial NO synthase (eNOS) expression and superoxide anion production. Results: Celiprolol inhibited intimal hyperplasia of carotid interposition-reversed jugular vein grafts 4 weeks after implantation (Intima/media index of celiprolol group, 0.48 ± 0.01 vs control group, 1.07 ± 0.08, P < .05) and suppressed cell proliferation in the neointima 2 weeks after implantation. In addition, celiprolol significantly enhanced endothelium-dependent NO-mediated relaxation in the vein graft with no change in eNOS expression and a reduction in superoxide production. Conclusions: These novel findings clearly demonstrate that β-adrenoceptor antagonist celiprolol can suppress intimal hyperplasia of the vein graft, which may be due to the enhancement of nitric oxide function through an inhibition of superoxide production. These results strongly support the clinical usefulness of celiprolol administration for preventing intimal hyperplasia of the vein graft after bypass grafting. [Copyright &y& Elsevier]

Background: The complexity of variables associated with vascular surgical site infections (VSSI) often contribute adversely to reinfection, limb salvage, and mortality rates. This report details our experience with the selective use of a sartorius muscle flaps (SMF) as part of an overall treatment strategy focused on staged surgical debridement (SSD) to control prosthetic graft bed infection prior to a graft preservation or revision plan. Methods: From our vascular registry, we identified 422 VSSI of which 89 (21%) had SMF for 24 aorto-bifemoral (ABF), 19 extra-anatomic bypasses (EAB), 34 infrainguinal bypasses, and 12 combined inflow/outflow reconstructions. All 86 patients had Szilagyi grade III prosthetic (Dacron-36, polytetrafluoroethylene [PTFE]-50) graft infections. The treatment algorithm included: SSD, culture-directed parenteral antibiotics, graft preservation (n = 3), or reconstruction (graft excision/EAB, n = 4; rifampin-bonded PTFE, n = 22; autologous conduit, n = 57) based on microbiology and consideration for SMF for extensive soft tissue defects (n = 43) or nonsterilized graft beds (n = 40). Analysis of microbiology, recurrent infection, vascular reconstruction, limb salvage, and mortality was completed over a mean follow-up of 52 months (range: 12 to 132 months). Results: Thirty-day mortality was 2% with two aortic graft infections dying from sepsis. Survival by life table analysis at 1, 3, and 5 years was 94%, 92%, and 90%, respectively. Wound isolates were most commonly gram positive organisms (n = 58, 65%), with gram negative isolates and mixed infections accounting for 19% and 10%, respectively. A single recurrent groin infection was documented at 30 days. Freedom from recurrent infection (n = 6) at 1 and 5 years was 98% and 92% by life tables. Methicillen-resistant Staphylococcus aureus (MRSA) was involved for 50% of reinfections. No amputations were attributable to uncontrolled VSSI and graft patency was 100% in surveillance monitored patients. Conclusion: These results suggest that selective utilization of SMF as part of SSD treatment plan in an attempt to achieve graft bed sterilization can effectively control the complex infectious process allowing for potentially improved outcomes for in situ or preservation graft salvage techniques. Lifelong graft surveillance is recommended. [Copyright &y& Elsevier]

Abstract: This paper reports investigation on the thermal performance of glazed solar chimney walls (GSCW) under the tropical climatic conditions of Thailand. The GSCW consisted of double glass panes with an air layer and openings located at the bottom (room side glass pane) and at the top (ambient side glass pane). A prototype of GSCW was integrated into the southern wall of a small room of 2.8m3 volume. Its dimensions were as follows: 0.74m height, 0.50m width and 0.10m air gap. The size of openings was 0.05×0.5m2. With a clear glass of 6mm thickness, velocity field measurement indicated that the induced airflow rate was about 0.13–0.28m3/s. The temperature difference between room and ambient was less than that with a single layer clear glass window. The reduction of daylight due to the double glass layer is negligible. Comparison between simulated and experimental results showed a reasonable agreement, therefore, the developed numerical model is valid and could be used as a tool for the design of GSCW. [Copyright &y& Elsevier]

Human papillomaviruses (HPVs) are recognized as important human pathogens, causing a spectrum of hyperproliferative lesions from benign warts to cervical dysplasias/carcinomas. HPV-associated lesions require continued production of the oncogenic E6/E7 proteins, which are encoded by either bicistronic or overlapping mRNAs. Here we targeted the E6/E7 mRNA of HPV11, a type implicated in causation of genital warts, using molecular reagents. Accessible sites in the HPV11E6/E7 RNA were identified using library selection protocols, and nucleic acids (DNAzymes, antisense oligonucleotides) targeted to these sites were constructed, and tested in cell culture and on human foreskin grafts. While DNAzymes were at least equally effective in cell culture, antisense oligonucleotides targeted to the region surrounding one of the library-selected sites (ASO407) proved most effective in blocking progression of HPV11-induced papillomas in human foreskin grafts on immunodeficient mice. In total, 11 papillomas were treated with ASO407. Of these, four of seven small papillomas treated with ASO407 showed loss of detectable virus by in situ hybridization (ISH), and in all four of these, papillomas were no longer evident grossly or histologically after treatment. When larger papillomas were treated, one of four showed loss of virus by ISH, associated with a minor decrease in papilloma size. Considering all 11 papillomas treated with ASO407, loss of viral staining by ISH was significantly different from that observed in controls (P<0.016), as was true for the seven small treated papillomas (P<0.012). DNAzymes targeted to the same site (or other library selected sites) did not produce statistically significant differences in ISH staining (P<0.15). Our results with ASO407 appear to represent the first specific molecular therapy against a bona fide HPV infection, and provide a rational proof-of-principle strategy for development of molecular therapeutics targeting other HPV-associated lesions.Gene Therapy (2004) 11, 1331-1341. doi:10.1038/sj.gt.3302303; Published online 1 July 2004 [ABSTRACT FROM AUTHOR]

Accidents with rupture of a reactor core can contaminate large regions. One way to reduce the time required to determine the scenario can be to perform a preliminary survey using nonspecialized dose rate meters placed on aircraft. For methodological support for this approach, an analytical relation is obtained which permits determining indirectly, on the basis of data on the flight altitude, the coefficients which are needed to convert the γ-ray dose rate measured from the aircraft to the value at the ground. [ABSTRACT FROM AUTHOR]

In this paper, we use a two-dimensional eddy-resolved model to investigate the instability of a parallel shear flow in a stably stratified boundary layer whose lower domain is occupied by a canopy. The results support our contention that wave motion in the canopy is initiated by shear in an air layer near the treetops. Significant modification by the wave motion of the mean velocity and temperature fields is found even before the wave reaches saturation. The wave fluxes of momentum and heat are not constant with height. Downwind tilting braids are found at the finite amplitude stage of the wave growth and could persist after wave breaking; these downwind tilting structures are believed to be the same as the temperature microfronts reported in the literature. We also present an analysis of the velocity and temperature fields of an observed wave event in the time-height domain and show that the simulation has captured the broad features of the observation. [ABSTRACT FROM AUTHOR]

Profile of sulfate aerosol (SO42-) concentration was measured for four days at six heights in and above a 15m-high canopy of pine plantation during 6th and 10th August. 1999. The concentration was the lowest (about 2 nmol/m3) on 6th, and gradually increased to 9th showing the maximum values of about 13 nmol/m3, and then decreased to 2 nmol/m3 on 10th. The vertical profiles of SO42- concentration showed mostly higher in the canopy than above the canopy. As for the vertical profiles above the canopy on 8th and 10th, the minimum was observed just above the canopy (16m), showing SO42- transport from the upper air layer to the canopy. While on 9th the profiles that are higher concentration just above the canopy and lower at the upper air layer were observed, suggesting SO42- emission from the canopy to the upper air layer. [ABSTRACT FROM AUTHOR]

Examines the role of vacuolar H[sup +]-ATPase (V-ATPase) in acidifying endomembrane compartments in eukaryotic cells. Identification of V-ATPase subunits by immunostaining; Details on the encoding of a 100 kDA subunit of the yeast V-ATPase; Existence of peripheral subunits.

1. Heather, Calluna vulgaris, can regenerate by layering (adventitious rooting) of stems. The frequency of layering stems, and strength of adventitious rooting, was surveyed in 11 stands (of 0·5-2ha each) at eight sites dispersed over the drier, eastern half of the northern British uplands at altitudes of 300-400m. Associated topographic, stem and stand structure characteristics were recorded, together with the composition of the litter and moss layer surrounding the stems. 2. Some adventitious roots were observed in over 50% of stems in all stands, and in 90% of stems in six stands. Strongly developed adventitious root systems were present on more than 30% of stems in seven of the stands. 3. Stem prostrateness and deeper humus-rich or peaty soil horizons were consistently associated with layering. Layering was associated with the absence or low abundance of Hypnum cupressiforme/jutlandicum and lichens (mainly Cladonia spp.). There was weak evidence that it may have been associated with the presence of Sphagnum spp., Leucobryum glaucum and pleurocarpous mosses other than Hypnum. More layering was observed in stands of younger mean age. Stands with strongly developed layering were more sheltered. 4. Strongly developed layering was associated with increased stem and canopy vigour distal to the point of rooting, and in some cases atrophy of the remaining part of the stem. This may lead to the in-filling of canopy gaps and to a reduction in the occurrence of conditions suitable for further layering. Continuity of layering and stability of Calluna cover is likely to require discontinuous Calluna cover. 5. The importance of layering has been underestimated in previous studies of Calluna dynamics which have focused mainly on stands burnt on regular, comparatively short rotations. This gap in understanding has management implications, particularly in upland Britain. Extensive areas of Calluna heathland in upland Britain are burnt infrequently, although the... [ABSTRACT FROM AUTHOR]

This study was conducted to determine the effects of indole-3-butyric acid (IBA) on the air-layering propagation of Jamaican ackee (Blighia sapida L.). Blighia sapida L. is a woody perennial, evergreen multipurpose fruit tree species native to the Guinean forests of West Africa. The fleshy arils of the ripened fruits are edible. All selected mother plants were fully grown mature, vigorous, healthy, and disease-free trees located within the landscape at The University of the West Indies, Cave Hill Campus. The experiment was laid out as a randomized block design with five different concentrations of the rooting hormone (0, 2000, 2500, 3000, and 3500 ppm) IBA and individual trees as blocks. The highest (100%) rooting success, maximum (108.0) number of roots, longest (16.0 cm) root length, and maximum (11.9 g) fresh weight and (3.7 g) dry weight of roots per stem were recorded in the treatment of 3500 ppm IBA. The results of this study can benefit fruits and nursery growers interested in propagating true-to-type Blighia sapida plants. [ABSTRACT FROM AUTHOR]

The article presents an unfinished research designed to test previous experiments on the relationship between the tree roots and the field layer. It highlights the procedures of the experiment, which was spread haltingly for several years, which aims to find out in which soil layers competition between roots and the roots of the field layer takes place or is more severe, and to test the validity of the concept that trees and the field layer are edaphically complementary and generally to discover the relation between the trees and the ground vegetation. It concludes that it appears that deeper lying tree roots may not be without influence on the welfare of the plants whose roots are restricted to the surface layers of the soil.

The aim of this study was to asses the clinical effectiveness of a low level laser therapy with respect to the acceleration of bone regeneration in dental post-operative particulate bone grafting of the extraction sockets. The stimulating effect of the red and near-infrared laser phototherapy on bone regeneration and growth has been shown in a number of in vitro and in animal studies. The stimulating effect of the red and near-infrared laser phototherapy on bone regeneration and growth has been shown in a number of in vitro and in animal studies.The effect of low level laser therapy on the regeneration of particulate bone allograft bone treated extraction socket has not been previously demonstrated. An OsseoPulse device Model AR 300 Bone Regeneration system was used daily for 21 days post extraction and socket grafting with a particulate allograft material (MinerOss, Biohorizons, Canada). Bone regeneration of the phototherapy treated and non treated sites were compared histological at different time intervals. Histological evaluations of the extraction sockets grafted with a particulate allograft showed enhanced bone formation and a faster resorption rate associated with the low level laser therary treatment compared with the non low level laser therary treated socket. The acceleration of the bone healing in the low level laser therary treated sockets grafts may provide a faster implant placement compared to the non treated sites. [ABSTRACT FROM AUTHOR]

Due to the continuous risk of rupture from endoleaks after endoluminal graft repair of thoracic aneurysms, the need for lifelong postoperative surveillance has become necessary. Patients are put at a lifetime risk of radiation exposure and may be at an increased risk of contrast induced nephropathy from routine contrast use during follow-up computed tomography for postoperative surveillance of endoluminal grafts. Measuring aneurysm sac pressures using remote wireless pressure sensor may provide a noninvasive method to detect endoleak, procedural success, and long-term stent graft stability. [Copyright &y& Elsevier]