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In the boreal forest of eastern North America, the distribution of eastern white cedar (Thuja occidentalis) is characterized by a latitudinal fragmentation gradient from south to north. Marginal populations could be outposts allowing cedar to expand its presence in the north in response to climate change. This study aimed to characterize the spatio-temporal regeneration dynamics of 20 marginal cedar stands in order to evaluate their expansion capacity into adjacent black spruce stands. Cedar recruitment within marginal cedar stands was mainly by layering, which allowed the species to maintain for a long time in the landscape. However, the rate of expansion of marginal stands into adjacent black spruce stands through seed dispersal was very low (0.28 m.year−1) and it was negatively influenced by distance to seed trees. Substrate had no significant effect. Global warming could lead to increased seed production by cedar, which could favour the species' expansion at its northern distribution limit. However, global warming could also increase the frequency and severity of wildfires, which would have a negative effect on cedar expansion capacity. [ABSTRACT FROM AUTHOR]

Double-skin facade (DSF) has been widely used in different kinds of architecture as new building envelopes. The position of the shading louver and opening size of the air layer is the key point to thermal performance of DSF. A temperature test, which is in a DSF building in Wuhan, has been conducted in this paper. The ANSYS software has also been used to simulate the velocity and temperature field in the DSF with different opening size. The results show that the test data keeps well accordance with the simulation. Significant differences exist in the velocity and temperature field in DSF with different shading louver position and opening size. The computing results in summer day indicate that as the opening size varies from 0.1m to 0.6m, temperature and velocity of the air in the layer decrease first, then remain the same. Temperature and velocity distribution becomes more regularly with the louver shading in the middle of the layer or near the outside glass than the region close to the inside glass. The testing data in sunny day keeps well accordance with the simulation result, which means the simulation results have certain reliability. [ABSTRACT FROM AUTHOR]

To properly predict thermal comfort using a thermal model of the human body, heat and moisture transfer in and around clothing as well as the thermophysiological response of the human body must be evaluated. Among the phases for modeling heat and moisture transfer in and around clothing, ventilation in the air layer in clothing is one of the most difficult elements to quantify. The low air velocity in clothing and the complex shape of the air layer complicates measurement. In this study, computational fluid dynamics (CFD) analysis around the human body considering the air layer in clothing was conducted instead of measurement. By importing three-dimensional (3D) shape data obtained by a laser scanner, the air distribution in and around clothing was observed by CFD analysis, for an adult human wearing single-layered clothing in typical indoor environmental conditions. The typical characteristics of the air flow around a clothed human body were clarified, and the influence of the ventilation of clothing air layers on the heat flux at the skin surface under the clothing was determined to be minimal. In addition, the results of the CFD analysis were consistent with those of a thermal manikin experiment, validating the CFD analysis. [ABSTRACT FROM AUTHOR]

The article discusses a study of three 18th and 19th century Chinese export lacquer objects. Topics include a discussion of factory-produced lacquerware in China for export to Europe and America; methods of analysis such as histochemical staining and pyrolysis gas chromatography-mass spectrometry with derivation by tetramethylammonium hydroxide (THMPy-GC-MS); and a discussion of the layering of lacquer, use of substrates, ground layers and fiber. Chemical analysis suggests laccol was derived mainly from Toxicodendron succedaneum or urushiol.

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]

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]

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]

The article focuses on the recommended use of green coating water than fluorocarbon-based materials. Topics discussed include the agglomeration of alumina nanoparticles, formation of air layer between water droplets and material surface, and identification of equivalence of contact angle of fluorocarbon-based superhydrophobic coatings.

The article presents abstracts on topics related to marine technology which include the study of air layer sustainability for frictional drag reduction, the use of Bayesian models for marine accident investigation in risk-based ship design, and the designing of blades for marine current turbines.

Because of their small size, rotary left ventricular assist devices (LVADs) can be implanted through several alternative approaches, including transdiaphragmatic LVAD insertion through a left subcostal incision with anastomosis of the outflow graft to the retroperitoneal supra-celiac aorta and a left thoracotomy approach with anastomosis to the descending thoracic aorta. More recently we have added a counter-incision to allow the outflow graft of a transdiaphragmatic LVAD to be tunneled through the right chest and anastomosed to the ascending aorta. However, constructing a tension-free, nonkinking lie of the outflow graft can be challenging. We have found that placing a 10-cm to 15-cm length of polytetrafluoroethylene graft coaxially over the LVAD outflow graft ensures a smooth, kink-free lie. Thus far 12 patients have undergone reinforcement of the LVAD outflow graft prior to graft-to-aorta anastomosis. In all cases, graft lie was facilitated and kinking was eliminated. [Copyright &y& Elsevier]

Summary: Replacement of the esophagus by colon interposition often has late complications, frequently due to technical defects. We report the case of a patient who presented 12 years after surgery with complex dysfunctions of a colonic interposition, including cervical and retrosternal strictures associated with a redundant portion of the colon graft. The interest of this case lies in its combination of many late complications of this surgery in a single person together with the simplicity of the treatment. [ABSTRACT FROM AUTHOR]

The removal of a surface air layer from a superhydrophobic coating in flowing water was evaluated using a laser beam and a high-speed camera. It proceeded via three steps: (1) removal of the top unstable air layer, (2) retention of air in the bottom of the surface microstructure, and (3) replacement of air in the microstructure with water. Different flow velocities result in different removal rates of the surface air layer. [ABSTRACT FROM AUTHOR]