Abstract Objectives To identify and analyse existing evidence from published studies evaluating the efficacy and safety of a percutaneous vessel closure device for the closure of large arterial ...femoral arterial access sites (≥10 French). Design This study was a systematic literature review and meta-analysis. Materials and methods Electronic databases were searched for studies published on the evaluation of the Prostar XL vessel closure device. There was no restriction by study design or patient population. Appraisal of studies for inclusion and data extraction were performed independently by two reviewers. Meta-analysis was performed where feasible. Results Twenty-one studies were included, which reported data specifically for closure of large (≥10 Fr) femoral arterial access sites using the Prostar XL device. The Prostar XL device, used for closure of these large femoral artery access sites, had a high rate of procedural success equal to that reported for closure by femoral artery surgical cut-down. There was evidence for reduced procedural time, time to discharge and time to ambulation. Complication rates were lower, but not significantly so, with Prostar XL vs. surgical cut-down. Conclusions The Prostar XL is an effective and safe device for use in percutaneous closure of large (≥10 Fr) femoral artery access sites, comparable to open surgical femoral artery cut-down. Furthermore, it may reduce procedure times and hospitalisations, thereby leading to potential cost savings.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Due to an increase in the number of users and a high demand for high data rates, researchers have resorted to boosting the capacity and spectral efficiency of the next-generation wireless ...communication. With a limited RF chain, hybrid analog digital precoding is an appealing alternative. The hybrid precoding approach divides the beamforming process into an analog beamforming network and a digital beamforming network of a reduced size. As a result, numerous hybrid beamforming networks have been proposed. The practical effects of signal processing in the RF domain, such as the additional power loss incurred by an analog beamforming network, were not taken into account. The effectiveness of hybrid precoding structures for massive MIMO systems was examined in this study. In particular, a viable hardware network realization with insertion loss was developed. Investigating the spectral and energy efficiency of two popular hybrid precoding structures, the fully connected structure, and the subconnected structure, it was found that in a massive MIMO, the subconnected structure always performed better than the fully connected structure. Characterizing the effect of quantized analog precoding, it was shown that the subconnected structure was able to achieve better performance with fewer feedback bits than the fully connected structure.
Erbium-substituted strontium stannates, with Er content 0≤x≤0.09, have been prepared by sol–gel method. The solubility limit of Er was found to be about 3%. The influence of temperature and the ...duration of the calcination, on the confirmation of single phase of Er doped SrSnO3 were investigated by using X-ray powder diffraction. The distribution of Er3+ in the crystal structure has been studied. Rietveld refinement of the data revealed that the crystal structure of the representative compound (Sr0.97Er0.03SnO3−δ) is orthorhombic perovskite (space group Pbnm). The cell dimensions are: a=5.7152(1) Å, b=5.7092(1) Å and c=8.0710(2) Å. The IR spectroscopy measurements of the samples with x≤0.03 were done in a wavelength range 400–2000cm−1 and confirmed the observed tilting in the SnO6 octahedra. The transport properties in the system Sr1−xErxSnO3−δ, x≤0.03, were investigated at high temperature. The Sr0.97Er0.03SnO3−δ compound exhibits semiconductive behaviour and the electrical transport mechanism agrees with the non-adiabatic small polaron hopping model between nominal states Sn4+/Sn2+ in the temperature ranges 350–525 and 525–693K separately.
The Sr0.97Er0.03SnO3−δ compound exhibits semiconductive behaviour and the electrical transport mechanism agrees with the non-adiabatic small polaron hopping model between nominal states Sn4+/Sn2+ Display omitted .
► Er showed a maximum solubility of 3mol% in SrSnO3 perovskite at 1173K. ► SnO6 octahedra in Sr1−xErxSnO3−δ are tilted. ► The expansion of the cell parameters ascribed to the apparition of Sn2+ ions. ► Transport mechanism in Sr0.97Er0.03SnO3−δ agrees with the non-adiabatic small polaron hopping model.
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Objectives The aim of this study was to assess the results of hybrid techniques for the treatment of thoracic, thoracoabdominal, and abdominal aortic aneurysms based on multicenter results and the ...various series regarding hybrid procedures reported in the literature. Methods The results of 76 hybrid procedures performed in 19 French university hospital centers between November 2001 and October 2011 were collected. There were 50 men and 26 women, mean age 68.2 (35–86) years. All patients were considered at high risk (ASA ≥ 3) for conventional surgery. Aneurysms involved the thoracic, abdominal, and thoracoabdominal aorta in five, 14, and 57 cases respectively. There were 11 emergent repairs. The revascularization of four visceral arteries was performed in 38 cases. Between one and three visceral arteries were revascularized in the other cases. Visceral artery debranching and stent graft deployment were performed in a one-stage procedure in 53 cases and in a two-stage procedure in 23 cases. Results There were 26 (34.2%) postoperative deaths. Nine of the survivors developed paraplegia, of which one resolved completely. Bowel ischemia occurred in 13 cases (17.1%), and one patient was treated by a superior mesenteric artery bypass. Four patients required long-term hemodialysis. Postoperative computed tomography scan showed a type II endoleak in two patients. Conclusions Morbidity and mortality in this study were greater than previously reported. Candidates for hybrid aortic repair should be carefully selected.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
A new compound LaSrCu
0.4
Al
0.6
O
4−
δ
has been prepared by sol gel method, annealed at 1623 K in oxygen gas flow and examined by X-ray diffraction. Rietveld refinement shows that the sample adopts ...the K
2
NiF
4
-type structure, space group I4/mmm (
a
= 3.7694(2) and
c
= 12.8248(5) Ǻ,
Z
= 2). Vibrational properties were investigated using Raman scattering and the most characteristic vibrations are discussed with reference to the available structural data. Differential thermal analysis shows two endothermic effects at 329 and 593 K and one exothermic at 693 K. Dielectric study as a function of temperature in the frequency range of 1 kHz–1 MHz has confirmed the observed phase transitions. The value of the measured dielectric constant depends on the frequency and undergoes a large increase near the phase transition temperatures indicating a diffuse behavior of these transitions. Variation of conductivity as a function of temperature shows that the compound has a semiconducting behavior. Oxygen vacancies could be the possible ionic charge carriers. The electrical transport mechanism agrees with Adiabatic Small Polaron Hopping model.
Abstract Purpose To compare the mid-term results following the use of bifurcated (ABIS) and aorto-uniiliac (AUIS) endovascular devices in the treatment of abdominal aortic aneurysms (AAA) in a ...population of patients deemed to be at high risk for open surgery. Material and methods Over a 4 year period (January 2003 to December 2007), 447 underwent elective endovascular aneurysm repair (EVAR) using ZENITH® stent-grafts. Group I comprised patients treated using the AUIS ( n = 124), and group II those receiving ABIS ( n = 323). Outcome measures included the assisted technical success rate, perioperative mortality, major complications, freedom from reintervention, and primary and secondary patencies. Factors associated with mid-term clinical failures were determined using univariate and multivariate analyses. Results The assisted primary technical success rate was 94% and 99% in groups I and II respectively ( p = .002). Major perioperative complications occurred in 13 group I patients (10%) vs. 12 group II patients (4%) ( p = .005). The 30-day mortality rate was 3.2% vs.1.5% ( p = 0.2). TASC C and D iliac lesions significantly increased the risk of major perioperative complications (35% vs. 3%; OR = 14.94; 95% CI: 5.75 to 38.78; p < .0001). During the follow-up period (median 24 months), secondary procedures were required in 11% and 5% of group I and group II patients respectively ( p = .01). Freedom from reintervention at 12, 24 and 36 months was 98%, 90%, and 85% in group I vs. 96%, 92%, and 92% in group II ( P < 0.005). The primary and secondary patency rates at 3 years were 92% vs. 98% ( p = .003) and 97% vs. 99% ( p = .04) for groups I and II respectively. In group I, the Crossover Femoro-Femoral Bypass (CFFB) was responsible for 3 major complications (2.4%) which occurred at 7, 12 and 57 months of follow-up. However, the use of AUIS with CFFB did not independently increase the risk of major complications during follow-up (HR = 0.108; 95% CI: 0.007 to 1.637; p = .11, Cox proportion model). In both univariate and multivariate analysis, concomitant iliac arterial occlusive disease (IAOD) was the only significant predictor of clinical failure in study population as a whole (OR = 3.996; 95% CI: 1.996 to 7.921; p < .0001). Conclusion This study demonstrates that ABIS is associated with better results than AUIS in the management of patients with AAA. Iliac artery occlusive disease was more frequently diagnosed in the AUIS group and this was significantly associated with a higher risk of complications, while the crossover graft itself was not. Nevertheless, the outcomes for both groups are encouraging in this high risk population.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The aim of this study was to investigate the relationship between enterprise risk management (ERM) and company ethics, so as to understand the central role of risk management in improving company ...ethics. A 5-point Likert scale questionnaire was used to survey all 122 employees of an insurance organization. The level of ethics was measured by posing questions on the integrity, trustworthiness, and level of respect for top management, middle management, and non-management. The overall Cronbach’s alpha for the instrument measuring the level of ethics was 0.865, indicating that the instrument was highly reliable.The relationship between ERM controls and the level of ethics was determined using regression analysis, which produced a F value of 0.268 (p-value 0.607), which implied that there is no relationship between ERM controls and the level of ethics. It was also ascertained that ethics and compliance-related issues are not fully embraced by the organization. This implied that the insurance company is at a level of “nominal” risk management with uncoordinated, top-down risk management activities.Since ethics risk exposure resulting from poor corporate governance has been identified by the Institute of Risk Management as being a key contributor to many business failures in South Africa (and internationally), the exploratory findings can stimulate the leadership to institute polices to mitigate poor governance and risk as this will benefit all stakeholders.
Physico-chemical analysis techniques, including X-ray diffraction and Scanning Electron Microscope–Energy Dispersive X-ray Spectroscopy, were employed to construct the isothermal section of the ...Er–Fe–Al system at 800
°C. At this temperature, the phase diagram is characterized by the formation of five intermediate phases, ErFe
12−
x
Al
x
with 5
≤
x
≤
8 (ThMn
12-type), ErFe
1+
x
Al
1−
x
with −0.2
≤
x
≤
0.75 (MgZn
2-type), ErFe
3−
x
Al
x
with 0.5
<
x
≤
1 (DyFe
2Al-type), Er
2Fe
17−
x
Al
x
with 4.74
≤
x
≤
5.7 (TbCu
7-type) and Er
2Fe
17−
x
Al
x
with 5.7
<
x
≤
9.5 (Th
2Zn
17-type), seven extensions of binaries into the ternary system; ErFe
x
Al
3−
x
with
x
<
0.5 (Au
3Cu-type), ErFe
x
Al
2−
x
with
x
≤
0.68 (MgCu
2-type), Er
2Fe
x
Al
1−
x
with
x
≤
0.25 (Co
2Si-type), ErFe
2−
x
Al
x
with
x
≤
0.5 (MgCu
2-type), ErFe
3−
x
Al
x
with
x
≤
0.5 (Be
3Nb-type), Er
6Fe
23−
x
Al
x
with
x
≤
8 (Th
6Mn
23-type), and Er
2Fe
17−
x
Al
x
with
x
≤
4.75 (Th
2Ni
17-type) and one intermetallic compound; the ErFe
2Al
10 (YbFe
2Al
10-type).
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