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Background Early coronary angiography (CAG) has been reported in individual studies and systematic reviews to significantly improve outcomes of patients with return of spontaneous circulation (ROSC) after cardiac arrest (CA). Methods We undertook a systematic review and meta-analysis to evaluate the impact of early CAG on key clinical outcomes in comatose patients after ROSC following out-of-hospital CA of presumed cardiac origin. We searched the PubMED, EMBASE, CINAHL, ERIC and Cochrane Central Register of Controlled Trials databases from 1990 until April 2020. Eligible studies compared patients undergoing early CAG to patients with late or no CAG. When randomized controlled trials (RCTs) existed for a specific outcome, we used their results to estimate the effect of the intervention. In the absence of randomized data, we used observational data. We excluded studies at high risk of bias according to the Robins-I tool from the meta-analysis. The GRADE system was used to assess certainty of evidence at an outcome level. Results Of 3738 citations screened, 3 randomized trials and 41 observational studies were eligible for inclusion. Evidence certainty across all outcomes for the RCTs was assessed as low. Randomized data showed no benefit from early as opposed to late CAG across all critical outcomes of survival and survival with favourable neurologic outcome for undifferentiated patients and for patient subgroups without ST-segment-elevation on post ROSC ECG and shockable initial rhythm. Conclusion These results do not support routine early CAG in undifferentiated comatose patients and patients without STE on post ROSC ECG after OHCA. Review registration PROSPERO — CRD42020160152.

International audience; BACKGROUND: Patients who have had a stroke with unknown time of onset have been previously excluded from thrombolysis. We aimed to establish whether intravenous alteplase is safe and effective in such patients when salvageable tissue has been identified with imaging biomarkers. METHODS: We did a systematic review and meta-analysis of individual patient data for trials published before Sept 21, 2020. Randomised trials of intravenous alteplase versus standard of care or placebo in adults with stroke with unknown time of onset with perfusion-diffusion MRI, perfusion CT, or MRI with diffusion weighted imaging-fluid attenuated inversion recovery (DWI-FLAIR) mismatch were eligible. The primary outcome was favourable functional outcome (score of 0-1 on the modified Rankin Scale [mRS]) at 90 days indicating no disability using an unconditional mixed-effect logistic-regression model fitted to estimate the treatment effect. Secondary outcomes were mRS shift towards a better functional outcome and independent outcome (mRS 0-2) at 90 days. Safety outcomes included death, severe disability or death (mRS score 4-6), and symptomatic intracranial haemorrhage. This study is registered with PROSPERO, CRD42020166903. FINDINGS: Of 249 identified abstracts, four trials met our eligibility criteria for inclusion: WAKE-UP, EXTEND, THAWS, and ECASS-4. The four trials provided individual patient data for 843 individuals, of whom 429 (51%) were assigned to alteplase and 414 (49%) to placebo or standard care. A favourable outcome occurred in 199 (47%) of 420 patients with alteplase and in 160 (39%) of 409 patients among controls (adjusted odds ratio [OR] 1·49 [95% CI 1·10-2·03]; p=0·011), with low heterogeneity across studies (I(2)=27%). Alteplase was associated with a significant shift towards better functional outcome (adjusted common OR 1·38 [95% CI 1·05-1·80]; p=0·019), and a higher odds of independent outcome (adjusted OR 1·50 [1·06-2·12]; p=0·022). In the alteplase group, 90 (21%) patients were severely disabled or died (mRS score 4-6), compared with 102 (25%) patients in the control group (adjusted OR 0·76 [0·52-1·11]; p=0·15). 27 (6%) patients died in the alteplase group and 14 (3%) patients died among controls (adjusted OR 2·06 [1·03-4·09]; p=0·040). The prevalence of symptomatic intracranial haemorrhage was higher in the alteplase group than among controls (11 [3%] vs two [\textless1%], adjusted OR 5·58 [1·22-25·50]; p=0·024). INTERPRETATION: In patients who have had a stroke with unknown time of onset with a DWI-FLAIR or perfusion mismatch, intravenous alteplase resulted in better functional outcome at 90 days than placebo or standard care. A net benefit was observed for all functional outcomes despite an increased risk of symptomatic intracranial haemorrhage. Although there were more deaths with alteplase than placebo, there were fewer cases of severe disability or death. FUNDING: None.

In-situ molecular beam epitaxy (MBE) Y 2 O 3 films 1–2 nm thick were epitaxially grown on GaAs(001)−4×6 reconstructed surfaces. Despite a large lattice mismatch, the hetero-structure exhibits outstanding thermal stability to 900 °C with excellent capacitance-voltage ( C-V ) characteristics. Low interfacial trap densities ( D it 's ) of (3–5)×10 11 eV −1 cm −2 were obtained using the conductance method ( G-V ) without discernible peaks at the mid-gap. The frequency dispersion of the measured C-V s of the Y 2 O 3 /GaAs(001) is ~4.6% for p -GaAs and ~12.4% for n -GaAs. In contrast, the atomic layer deposited Al 2 O 3 on GaAs(001) shows large D it with a peak at the mid-gap, large C-V frequency dispersion, and low thermal stability at temperatures higher than 600 °C. Synchrotron radiation photoemission results show intactness of the interfacial structure in the MBE-Y 2 O 3 /GaAs, while removal of the surface As atoms is found in the ALD-Al 2 O 3 /GaAs system.

Bone biopsies are traditionally performed using manual drill devices. More recently, powered drill biopsy systems have been developed, ostensibly to improve diagnostic yield. We compare the powered drill biopsy system to traditional manual needle devices on the basis of diagnostic yield, specimen size and material costs. 309 consecutive bone biopsy procedures performed with imaging guidance from a single academic institution were retrospectively reviewed. Specimen diagnostic adequacy, qualitative interpretation of diagnostically inadequate specimens, aggregate specimen volume and material costs were assessed. Econometric analysis was performed to assess the relationship between materials cost and diagnostic yield. Diagnostic yield and average core specimen volume were significantly higher in the powered drill group, with 86% of cases yielding adequate biopsy specimens versus 67% of cases using the manual method. The materials cost associated with the powered drill device was higher than those of any of the manual needle devices with an average difference of $270.19 per case, however, this was offset due to higher diagnostic yield suggesting that the increased diagnostic accuracy achieved by the powered drill does not carry a significant added financial burden. The powered drill bone biopsy system results in a significantly higher yield of diagnostically adequate biopsy specimens compared to traditional manual needles, possibly attributed to larger and more intact obtained core specimen volumes and is more economically viable off-setting the higher cost.

Stroke thrombolysis with alteplase is currently recommended 0-4·5 h after stroke onset. We aimed to determine whether perfusion imaging can identify patients with salvageable brain tissue with symptoms 4·5 h or more from stroke onset or with symptoms on waking who might benefit from thrombolysis.In this systematic review and meta-analysis of individual patient data, we searched PubMed for randomised trials published in English between Jan 1, 2006, and March 1, 2019. We also reviewed the reference list of a previous systematic review of thrombolysis and searched ClinicalTrials.gov for interventional studies of ischaemic stroke. Studies of alteplase versus placebo in patients (aged ≥18 years) with ischaemic stroke treated more than 4·5 h after onset, or with wake-up stroke, who were imaged with perfusion-diffusion MRI or CT perfusion were eligible for inclusion. The primary outcome was excellent functional outcome (modified Rankin Scale [mRS] score 0-1) at 3 months, adjusted for baseline age and clinical severity. Safety outcomes were death and symptomatic intracerebral haemorrhage. We calculated odds ratios, adjusted for baseline age and National Institutes of Health Stroke Scale score, using mixed-effects logistic regression models. This study is registered with PROSPERO, number CRD42019128036.We identified three trials that met eligibility criteria: EXTEND, ECASS4-EXTEND, and EPITHET. Of the 414 patients included in the three trials, 213 (51%) were assigned to receive alteplase and 201 (49%) were assigned to receive placebo. Overall, 211 patients in the alteplase group and 199 patients in the placebo group had mRS assessment data at 3 months and thus were included in the analysis of the primary outcome. 76 (36%) of 211 patients in the alteplase group and 58 (29%) of 199 patients in the placebo group had achieved excellent functional outcome at 3 months (adjusted odds ratio [OR] 1·86, 95% CI 1·15-2·99, p=0·011). Symptomatic intracerebral haemorrhage was more common in the alteplase group than the placebo group (ten [5%] of 213 patients vs one [1%] of 201 patients in the placebo group; adjusted OR 9·7, 95% CI 1·23-76·55, p=0·031). 29 (14%) of 213 patients in the alteplase group and 18 (9%) of 201 patients in the placebo group died (adjusted OR 1·55, 0·81-2·96, p=0·66).Patients with ischaemic stroke 4·5-9 h from stroke onset or wake-up stroke with salvageable brain tissue who were treated with alteplase achieved better functional outcomes than did patients given placebo. The rate of symptomatic intracerebral haemorrhage was higher with alteplase, but this increase did not negate the overall net benefit of thrombolysis.None.

Display Omitted First demonstration of single-crystal atomic layer deposited oxide on GaAs(001).Attainment of very thin single crystal ALD-Y2O3 1nm thick on GaAs(001).Thin ALD-Y2O3 film with excellent crystallinity having FWHM of ~0.033?.Lowest frequency dispersion ever achieved in the ALD-oxides on n-type GaAs(001).Thermodynamic stability at high temperatures of 900?C. In situ atomic layer deposited (ALD) Y2O3 films 1-5nm thick on GaAs(001)-4i?6 reconstructed substrates were found to be single crystalline. The epitaxial growth between the oxide films and GaAs was first observed using reflective high energy electron diffraction (RHEED) and later studied using high-resolution synchrotron radiation X-ray diffraction. The Y2O3 films are of cubic phase and have (110) as the film normal; the orientation relationship between the Y2O3 films and the GaAs substrates was determined to be Y2O3(110)001] 1 ? 1 0 ]//GaAs(001)110] 1 1 ? 0 ] . The frequency dispersion of the measured capacitance-voltage (C-V) curves of the single crystal ALD-Y2O3/GaAs(001)-4i?6 is ~7% for p-GaAs and ~14% for n-GaAs (1MHz to 100Hz), lowest ever achieved in the ALD-oxides on GaAs(001).

The effect of Mo additions on the development of bainitic ferrite in hot rolled low carbon (0·05 wt-%C) Nb containing steel strips has been studied. The steel strips were fabricated by a combined process of controlled rolling and accelerated cooling. Microstructural characterisation and mechanical testing for the corresponding strips were investigated. The results indicated that a small amount of Mo addition (0·1–0·3 wt-%) causes the production of a high volume fraction of bainite, which undergoes significant secondary hardening after tempering treatment at 600°C for 1 h. It is noticeable that the secondary hardening effect provides an additional way to significantly increase the strength of low carbon Nb–Mo containing bainitic steels.

This article proposes a new logarithmic approximate formula of the Arrhenius temperature integral p(u) for non-isothermal analysis using the Solver algorithm. The proposed formula is presented as and the values for a, b and c are 0.69038, 1.71975 and 1.01249, respectively, for 0.45891, 1.85919 and 1.00275, respectively, for and 0.27341, 1.93235 and 1.00060, respectively, for The validity of the proposed Arrhenius temperature integral formula has been tested by investigating the thermal decomposition kinetics of acrylonitrile–butadiene–styrene (ABS). The activation energy and the pre-exponential factor determined by the proposed formula are 48.7385 kcal mol−1 and 2.6 × 1016 s−1, respectively. The reaction model of ABS thermal decomposition obtained with the method of master plots indicates that the phase boundary reaction model best describes the thermal decomposition reaction of ABS. The accuracy of the proposed Arrhenius temperature integral formula has also been tested by numerical analysis, and deviati...

A new formula for approximating the Arrhenius temperature integral for nonisothermal analysis has been developed, using the Solver algorithm. The new formula takes the form p(u)=(e−u/u2)×[(1−2/u)/(1−λ/u2)], where λ=0.33 ln(u)+4.48. Applicability of the formula has been proven by conducting thermogravimetric analysis experiments on polypropylene material. When simulated thermogravimetric analysis curves derived from the proposed approximation were compared with curves obtained from other published approximate formulae, the new approximation fit the experimental data very well. Numerical analysis was used to test accuracy of the proposed formula, and its deviation from the numerical value was compared with those of other published approximation formulae. Results show that the new formula is a suitable solution for the evaluation of kinetic parameters for nonisothermal kinetic analysis, for example, pyrolysis of polymeric wastes and biomass fuel or to produce biomass fuel. Its use will result in sig...

Manganese-doped zinc oxide (Mn-doped ZnO) thin films were prepared using chemical bath deposition (CBD), and the impacts of the manganese dopant concentration on the structure, electrical resistivity, optical transmission, and magnetic properties were investigated using x-ray diffractometry, Hall-effect measurements, ultraviolet–visible–near-infrared (UV–Vis–IR) spectrophotometry, and vibrating sample magnetometry (VSM), respectively. The concentration of the manganese dopant in the ZnO thin film critically impacted the resulting properties, and the 4.0 at.% Mn-doped ZnO film had a resistivity of 5.8 × 10−2 Ωcm, transmittance of 75.6% in the visible light range, and bandgap of 3.30 eV when the film was annealed at 600°C in an Ar + H2 atmosphere. Annealing the film could enhance its magnetic properties such that the film had a saturation magnetization of 21.0 emu/cm3 and a coercivity of 45.7 Oe after annealing at 600°C. Because of these electrical, optical, and magnetic properties, Mn-doped thin films are promising for use in spintronic devices.

Conformational changes of xanthan gum as a function of concentration were investigated to elucidate its unusual flux behavior during ultrafiltration (UF). The contribution of hydrogen bonding on structure formation and the molecular orientation of xanthan gum on the flow characteristics were studied rheomechanically and rheo-optically. Known to affect xanthan structure at low concentrations, hydrogen bonding unexpectedly did not show significant influence on xanthan rheological properties up to 2 wt %. The ordered layers formed on the membrane surface proved responsible for the enhanced water removal during UF. This unique behavior could be attributed to the formation of aligned molecular orientation in addition to the viscosity increases during the biphasic region. Significant differences were observed between xanthan fermentation broth and solutions made of commercial xanthan, suggesting the need to control the salt concentration in fermentation broth in order to make UF an effective recovery process for xanthan gum after fermentation. PRACTICAL APPLICATIONS The knowledge gained from the present study strengthens fundamental understandings on the conformational changes of xanthan biopolymers during the recovery of xanthan gum from fermentation broth using ultrafiltration (UF). By taking advantage of the aligned molecular orientation, along with controlling the salt concentration in the fermentation broth, UF could be operated at elevated flux to speed up the removal of water from the viscous fermentation broth. The technology should find broad applications in the fermentation industry, especially where viscosity is of concern during the separation and purification of the product.

The epitaxial growth of GaN on Si (111) substrates has been performed using plasma-assisted molecular beam epitaxy with a thin (∼19.3 nm) single-crystal layer of Sc 2 O 3 as a template/buffer layer. The structural properties and in situ epitaxial growth were studied using reflection high energy electron diffraction (RHEED), high-resolution transmission electron microscopy, and high-resolution X-ray diffraction. An orientation relationship of GaN(0 0 0 2)IISc 2 O 3 (111)∥Si(111) and GaN[1010]∥Sc 2 O 3 [422] off 60° with Si[422] was determined. The excellent growth of Sc 2 O 3 on Si and GaN on Sc 2 O 3 was achieved, as observed from streaky and bright RHEED patterns. The Sc 2 O 3 template serves as an effective barrier layer preventing diffusion of Si and Ga during the GaN growth at high temperatures under nitrogen plasma. No cracking was observed in the GaN layer with thickness around 0.2 μm when inspected with an optical microscope.

MuGFET structure improves local transistor mismatch compared to planar bulk MOSFET. This enables further SRAM cell size reduction. GIDL current is well controlled even with a mid-gap metal gate. MuGFETs have low subthreshold leakage if Lg/Wsi ratio is kept above 1.5. The advantage of MuGFET subthreshold leakage suppression is even more pronounced at higher temperatures. Furthermore MuGFETs are compatible with local strain techniques to improve carrier mobility. The aforementioned qualities, along with low manufacturing cost of single mid- bandgap metal gate, make MuGFET a good candidate to replace planar bulk MOSFET for Low-Power Applications.

High-quality epitaxial Fe 3 Si films (1 0 0) were grown on the GaAs (1 0 0) surface using molecular beam epitaxy (MBE). High-resolution X-ray diffraction analysis using an X-ray energy of 12.38 keV from synchrotron radiation gave a narrow rocking curve of ∼0.014° for the Fe 3 Si (0 0 6) reflection, with a lattice mismatch between the film and GaAs of ∼0.25% in the normal direction. Square-shaped M–H loops with a typical moment of 660 emu/cm 3 at 10 K and the easy axis along [1 0 0] were obtained for films grown at a substrate temperature ( T s ) of 150 °C, and the M–H loops at low fields show fine features for films grown at a T s of 200–300 °C. A two-step growth procedure with the initial growth at 150 °C and subsequently ramping to 250 °C was applied to minimize the interfacial reactions, thus to achieve abrupt interfaces.

A nearly lattice-matched Gd2O3/Si(1 1 1) hetero-epitaxy was demonstrated using molecular beam epitaxy (MBE). Detailed structural studies find that the nano thick Gd2O3 films have a cubic phase with a very uniform thickness, an excellent crystallinity and atomically sharp interfaces. These features are characterized by the bright, streaky reconstructed reflection high-energy electron diffraction (RHEED) patterns at the initial oxide growth, the pronounced interference fringes in the X-ray reflectivity curve as well as in the crystal truncation rod around the substrate diffraction peaks using the high-resolution X-ray diffraction. The (1 1 1) axis of the thin oxide is oriented parallel to the substrate (1 1 1) normal with a 60° in-plane symmetry rotation.

Thermal/residual deformations and stresses in plastic integrated circuit (IC) packages caused by epoxy molding compound (EMC) during the manufacturing process are investigated experimentally (only for deformations), theoretically, and numerically. A real-time Twyman-Green interferometry is used for measuring the out-of-plane thermal and residual deformations of die/EMC bi-material specimens. Dynamic mechanical analysis (DMA) and thermomechanical analysis (TMA) are for characterizing thermomechanical properties of the EMC materials. A finite element model (FEM) and theory associated with experimental observations are employed for understanding the thermal/residual deformations and stresses of IC packages due to EMC encapsulation. It is shown that EMC materials must be fully cured so that the material properties are stable enough for applications. Experimental results show that the EMC material experiences stress relaxation due to its viscoelastic behavior during the post mold curing (PMC) process. As a result, the strains (stresses) resulted from the chemical shrinkage of the EMC curing could be relaxed during the PMC process, so that the chemical shrinkage has no effect on the residual strains (stresses) for the plastic packages being post cured. Compared with numerical and theoretical analyses, the experimental results have demonstrated that die/EMC bi-material structure at high temperature (above Tg) warps less than expected, as a result of viscoelastic stress relaxation of EMC at high temperature (during solder reflow process). Meanwhile, this stress relaxation can also cause shifting this zero-stress temperature to the higher one, so that the residual deformations (stresses) of die/EMC bi-material specimens were found to increase by about 40% after the solder reflow process. The residual and thermal stresses have been resolved by FEM and theoretical analyses. The results suggest that the pure bending stresses (without shear and peel stresses) of the bi-material specimens are only limited in the region from x= 0 (the center) to x= 0.75 L due to the free edge effects, but this region is shrunk down to x= 0.4L at 200degC. And the maximum warpage and bending stress per unit temperature change is occurred around 165degC (Tg of the EMC). This study has demonstrated that the Twyman-Green experiment with associated bi-material plate theory and FEM can provide a useful tool for studying the EMC-induce residual/thermal deformations and stresses during the IC packaging fabrication

The production of xanthan gum, an industrially important microbial exopolysaccharide, was enhanced by using Xanthomonas campestris cells adsorbed to cotton fibers. However, the function of xanthan polymers during cell adsorption has not been elucidated. Polyethylenimine (PEI), a cationic polyelectrolyte, was employed to investigate respective effects of fiber surface properties and xanthan polymers during cell adsorption. Adsorption of X. campestris cells to fiber was independent of fiber roughness and hairiness, and the effect of electrostatic interactions between cells and fiber was insignificant. Fiber hydrophilicity was critical in initiating cell-fiber contacts, whereas xanthan polymers enhanced retention of cells on fiber surface. The untreated cotton showed the highest immobilization efficiency and xanthan production.

The evolution of the surface morphology of ordered, self-organized Ge nanodots samples by sputtering with various Ar+ ion energy and density has been investigated. Under low (300 eV) ion energy irradiation the surface smoothing mechanism dominates surface relaxation processes. The result indicates that ion sputtering with low ion energy can be utilized as an effective method for the preparation of ultra-smooth surfaces. In addition, with medium ion energy (650 eV) irradiation, the Ge nanodots transform into pure Si dots with the same shape characteristics as the unsputtered nanodots.

Biofilms were used to produce gramicidin S (a cyclic decapeptide) to inhibit corrosion-causing, sulfate-reducing bacteria (SRB). In laboratory studies these biofilms protected mild steel 1010 continuously from corrosion in the aggressive, cooling service water of the AmerGen Three-Mile-Island (TMI) nuclear plant, which was augmented with reference SRB. The growth of both reference SRB (Gram-positive Desulfosporosinus orientis and Gram-negative Desulfovibrio vulgaris) was shown to be inhibited by supernatants of the gramicidin-S-producing bacteria as well as by purified gramicidin S. Electrochemical impedance spectroscopy and mass loss measurements showed that the protective biofilms decreased the corrosion rate of mild steel by 2- to 10-fold when challenged with the natural SRB of the TMI process water supplemented with D. orientis or D. vulgaris. The relative corrosion inhibition efficiency was 50-90% in continuous reactors, compared to a biofilm control which did not produce the antimicrobial gramicidin S. Scanning electron microscope and reactor images also revealed that SRB attack was thwarted by protective biofilms that secrete gramicidin S. A consortium of beneficial bacteria (GGPST consortium, producing gramicidin S and other antimicrobials) also protected the mild steel.

The corrosion behavior of cartridge brass (UNS C26000) exposed to artificial seawater (AS) and Luria Bertani (LB) medium has been studied using electrochemical impedance spectroscopy. Tests were performed in sterile media and in the presence of a Bacillus subtilis bacterial biofilm. Additional tests were performed in the presence of a B. subtilis bacterial biofilm that produced polyaspartate or a B. licheniformis biofilm that produced γ-polyglutamate. A significant reduction of corrosion rates and an ennoblement of the corrosion potential were observed in both media in the presence of the biofilms. Samples exposed in the presence of biofilms remained untarnished and unattacked for time periods exceeding one week, while samples exposed in the sterile solutions were covered with a dark film of corrosion products.

EIS has been used to follow the pitting process of Al 2024 during exposure to sterile artificial seawater (AS) for 30 days. In the presence of a bacterial biofilm produced by Bacillus subtilis pitting was also observed during the first two days, however for the remainder of the exposure period the Al alloy was passive. When the biofilm was genetically engineered to secrete polyglutamate or polyaspartate, an additional small increase in corrosion inhibition occurred. Corrosion control using regenerative biofilms (CCURB) on Al 2024 in AS cannot be solely due to a reduction of the oxygen concentration at the metal surface since the experimental values of the corrosion potential E corr became more noble in the presence of bacteria suggesting that production of an inhibiting species retained in the biofilm contributes to CCURB.

A theoretical and experimental analysis of the effects of trends in the potential and current noise fluctuations observed during measurement of electrochemical noise (ECN) data on the slopes of power spectral density and spectral noise plots as well as various other parameters obtained by statistical analysis of the ECN data in the time domain has been carried out. Drifts in the ECN data can affect the calculated values of the standard deviations of the potential ( σ V ) and current ( σ I ) fluctuations and the noise resistance R n . Correction formulae developed based on previous literature data have been used to correct the experimental data. A linear method has been applied to remove the trend from the experimental data for the mild steel/NaCl system and good agreement has been obtained between σ V , σ I and R n calculated from the data after trend removal and from the correction formulae. The localization index (LI) was 1.00 after trend removal in all cases demonstrating that LI is not related to a particular corrosion mechanism. A good agreement has been obtained between the spectral noise plots after trend removal and the impedance spectra determined at the same exposure time. A moving average removal method discussed in the literature was found to produce erroneous data.

Methane emissions from a flock of 14, 1-year old sheep grazing on a grass and legume pasture were measured using a micrometeorological mass-balance method and a sulphur hexaflouride (SF 6 ) tracer technique. The former measured the mean emission, over 45 min intervals, from all the sheep within a fenced 24 m×24 m enclosure, from the enrichment of methane (CH 4 ) in air as it passed over the sheep. The tracer technique measured emissions from a subset of 7 individual animals over 24 h periods from measurements of CH 4 and SF 6 concentrations in air exhaled by the sheep, and from the known rate of release of SF 6 from small permeation tubes placed in the animals’ rumens. Both methods gave highly similar results for 4 out of 5 days. When the species composition of dietary intake was steady during the last two days of measurement, the mean emission rate from the mass-balance method was 11.9±1.5 (SEM) g CH 4 sheep -1 d -1 , while the rate from the tracer technique was 11.7±0.4 (SEM) g CH 4 sheep -1 d -1 . These rates are for sheep with mean live mass of 27 kg, with a measured dry matter intake of 508 g sheep -1 d -1 and pasture dry matter digestibility of 69.5%. There was close agreement between these measurements and estimates from algorithms used to predict methane emissions from sheep for the Australian National Greenhouse Gas Inventory.

A flow model utilizing an irrotational, inviscid algorithm of vortex-ring elements simulating the leaflets and source/sink elements simulating the aortic root coupled with a boundary layer model has been developed to model the internal flow phenomena of bi-leaflet mechanical heart valves implanted in the aortic root. The inviscid representation evaluates the aerodynamic lift, the induced drag, the pitching moment and flow velocity along the leaflet surface thus providing data for evaluating the boundary-layer thickness, the shear stress and flow separation point by the boundary layer theory. Full integration with the geometry enables immediate updates of the flow solution when changes in geometry have been made. It is shown that the effects of the internal flow domain model are necessary in the correct evaluation of lift and drag for subsequent dynamic analysis. The environment presented provides for the ability to produce significant and immediate design changes so that crucial decisions may be made whilst still within the software design loop. New designs are shown along with data for the improved flow model.

High-K/Metal-Gate (HK/MG) reliability TDDB and BTI are investigated systematically for the first time through HfZrO x gate stack engineering. To meet reliability requirements, it is shown that the HK film thickness, the position and concentration of a Zr dopant, utilizing post deposition anneal (PDA), and decoupled plasma nitridation (DPN) are important factors.

For pt.I see ibid., vol.2, p. 33 (1993). Strong capillary forces are developed in the fabrication process of surface micromachined structures during the wet etch of sacrificial layers. The magnitude of these forces is in some cases sufficient to deform and pin these structures to the substrate resulting in device failure. The deflection, mechanical stability, and adhesion of thin micromechanical structure under capillary forces are examined. Microstructure adhesion is considered and experimental data for polycrystalline silicon microstructures are presented. >

Strong capillary forces are developed in the fabrication process of surface micromachined structures during the wet etch of sacrificial layers. The magnitude of these forces is in some cases sufficient to deform and pin these structures to the substrate resulting in device failure. The deflection, mechanical stability, and adhesion of thin micromechanical structure under capillary forces are examined. These phenomena are divided into two separate stages of mechanical collapse and adhesion to the underlying substrate. The basic theory of collapse is described. Approximate conditions are computed to prevent contact to the substrate. >

In this study we evaluate the information and interface design of the shopping website, in order to better understand how to provide service suited to the customer. The internet consumer behavior model forms the structural basis of the examination. An evaluation form was designed based on this model and used to examine 351 domestic and foreign shopping websites, for information and interface design. Comparisons were made between websites related to the aspects of product category, behavioral step, and domestic/foreign websites. The results can serve as useful reference for website owners and designers to provide consumers with more convenient and barrier-free shopping environments.

An analytic potential DG model with quantum mechanical and short channel effects is calibrated to experimental n-channel FinFET data. All C-V and I-V curves from L=10 mum to 50 nm are in excellent agreement with a single mobility model. There is evidence suggesting higher than expected currents from very short fins possibly due to strain enhanced transport effects.

The origin of the large Vt shift observed in planar FDSOI is the creation of negative charge states in the BOX by F implant. F implant is a suitable approach for planar FDSOI SoC integration with single WF metal gate, but NOT for MuGFETs. F implant degrades electron mobility and the degradation is a function of F dose. The hole mobility is unaffected by F implant.

This paper reviews MuGFET (multi-gate MOSFET) devices performance under extreme temperature range (5-573 K) and total radiation dose up to 6 Mrad. It is concluded that MuGFET is not only a good platform for CMOS scaling, but also an excellent platform for operation in harsh environments.

Multiple-gate-MOSFETs (MuGFET) have better short-channel effects (SCE) control than planar MOSFET and MuGFETs are good candidates to replace planar bulk MOSFET for low power applications. A key feature in the MuGFETs is the recess and undercut of the fins in the buried oxide. Undercut improves gate control of the channel at fin and BOx interface, but also undermines the fin stability, and increases susceptibility to gate etch defects. This paper introduces SOI wafers with nitride buried dielectric that eliminates the undercut, while maintaining good gate control of the channel through higher buried insulator dielectric constant.

This paper reports an analytical drain current model of double-gate (DG) fully-depleted (FD) SOI NMOS devices with the n+/p+ poly top/ bottom gate considering the threshold/ transition voltage effects. Via a comprehensive current conduction mechanism model, the analytical drain current model considering the threshold/transition voltage effects could provide an accurate prediction of performance the 100 nm DG FD SOI NMOS device with the n+/p+ poly top/bottom gate as verified by the 2D simulation results.

This paper reports the gate-misalignment-effect related capacitance behavior of a 100nm double-gate (DG) fully-depleted (FD) SOI NMOS device with the n+p+poly top/bottom gate. Based on the 2D simulation result, with the gate misalignment, the sudden fall in the gate-drain/source capacitance (C GD /C GS ) of the device at V G =0.5V is mitigated due to the reduced hole accumulation/ depletion in the bottom channel controlled by the p+bottom gate with the increased fringing electric field effect.