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Review of public comments on proposed seismic design criteria
During the first quarter of 1988, the Nuclear Regulatory Commission (NRC) prepared a proposed Revision 2 to the NUREG-0800 Standard Review Plan (SRP) Sections 2.5.2 (Vibratory Ground Motion), 3.7.1 (Seismic Design Parameters), 3.7.2 (Seismic Systems Analysis) and 3.7.3 (Seismic Subsystem Analysis). The proposed Revision 2 to the SRP was a result of many years' work carried out by the NRC and the nuclear industry on the Unresolved Safety Issue (USI) A-40: ''Seismic Design Criteria.'' The background material related to NRC's efforts for resolving the A-40 issue is described in NUREG-1233. In June 1988, the proposed Revision 2 of the SRP was issued by NRC for public review and comments. Comments were received from Sargent and Lundy Engineers, Westinghouse Electric Corporation, Stevenson and Associates, Duke Power Company, General Electric Company and Electric Power Research Institute. In September 1988, Brookhaven National Laboratory (BNL) and its consultants (C.J. Costantino, R.P. Kennedy, J. Stevenson, M. Shinozuka and A.S. Veletsos) were requested to carry out a review of the comments received from the above six organizations. The objective of this review was to assist the NRC staff with the evaluation and resolution of the public comments. This review was initiated during October 1988 and it was completed on January 1989. As a result of this review, a set of modifications to the above mentioned sections of the SRP were recommended by BNL and its consultants. This paper summarizes the recommended modifications. 4 refs
Winter Wheat Grain Yield Response to Fungicide Application is Influenced by Cultivar and Rainfall
Winter wheat is susceptible to several fungal pathogens throughout the growing season and foliar fungicide application is one of the strategies used in the management of fungal diseases in winter wheat. However, for fungicides to be profitable, weather conditions conducive to fungal disease development should be present. To determine if winter wheat yield response to fungicide application at the flowering growth stage (Feekes 10.5.1) was related to the growing season precipitation, grain yield from fungicide treated plots was compared to non-treated plots for 19 to 30 hard red winter wheat cultivars planted at 8 site years from 2011 through 2015. At all locations, Prothioconazole + Tebuconazole or Tebuconazole alone was applied at flowering timing for the fungicide treated plots. Grain yield response (difference between treated and non-treated) ranged from 66-696 kg/ha across years and locations. Grain yield response had a positive and significant linear relationship with cumulative rainfall in May through June for the mid and top grain yield ranked cultivars (R2=54%, 78%, respectively) indicating that a higher amount of accumulated rainfall in this period increased chances of getting a higher yield response from fungicide application. Cultivars treated with a fungicide had slightly higher protein content (up to 0.5%) compared to non-treated. These results indicate that application of fungicides when there is sufficient moisture in May and June may increase chances of profitability from fungicide application
Fractional flow reserve vs. angiography in guiding management to optimize outcomes in non-ST-segment elevation myocardial infarction: the British Heart Foundation FAMOUS-NSTEMI randomized trial
Aim: We assessed the management and outcomes of non-ST segment elevation myocardial infarction (NSTEMI) patients randomly assigned to fractional flow reserve (FFR)-guided management or angiography-guided standard care.
Methods and results: We conducted a prospective, multicentre, parallel group, 1 : 1 randomized, controlled trial in 350 NSTEMI patients with ≥ coronary stenosis ≥30% of the lumen diameter assessed visually (threshold for FFR measurement) (NCT01764334). Enrolment took place in six UK hospitals from October 2011 to May 2013. Fractional flow reserve was disclosed to the operator in the FFR-guided group (n = 176). Fractional flow reserve was measured but not disclosed in the angiography-guided group (n = 174). Fractional flow reserve ≤0.80 was an indication for revascularization by percutaneous coronary intervention (PCI) or coronary artery bypass surgery (CABG). The median (IQR) time from the index episode of myocardial ischaemia to angiography was 3 (2, 5) days. For the primary outcome, the proportion of patients treated initially by medical therapy was higher in the FFR-guided group than in the angiography-guided group [40 (22.7%) vs. 23 (13.2%), difference 95% (95% CI: 1.4%, 17.7%), P = 0.022]. Fractional flow reserve disclosure resulted in a change in treatment between medical therapy, PCI or CABG in 38 (21.6%) patients. At 12 months, revascularization remained lower in the FFR-guided group [79.0 vs. 86.8%, difference 7.8% (−0.2%, 15.8%), P = 0.054]. There were no statistically significant differences in health outcomes and quality of life between the groups.
Conclusion: In NSTEMI patients, angiography-guided management was associated with higher rates of coronary revascularization compared with FFR-guided management. A larger trial is necessary to assess health outcomes and cost-effectiveness
Agent-based autonomous systems and abstraction engines: Theory meets practice
We report on experiences in the development of hybrid autonomous systems where high-level decisions are made by a rational agent. This rational agent interacts with other sub-systems via an abstraction engine. We describe three systems we have developed using the EASS BDI agent programming language and framework which supports this architecture. As a result of these experiences we recommend changes to the theoretical operational semantics that underpins the EASS framework and present a fourth implementation using the new semantics
Local Unit Invariance, Back-Reacting Tractors and the Cosmological Constant Problem
When physics is expressed in a way that is independent of local choices of
unit systems, Riemannian geometry is replaced by conformal geometry. Moreover
masses become geometric, appearing as Weyl weights of tractors (conformal
multiplets of fields necessary to keep local unit invariance manifest). The
relationship between these weights and masses is through the scalar curvature.
As a consequence mass terms are spacetime dependent for off-shell gravitational
backgrounds, but happily constant for physical, Einstein manifolds.
Unfortunately this introduces a naturalness problem because the scalar
curvature is proportional to the cosmological constant. By writing down tractor
stress tensors (multiplets built from the standard stress tensor and its first
and second derivatives), we show how back-reaction solves this naturalness
problem. We also show that classical back-reaction generates an interesting
potential for scalar fields. We speculate that a proper description of how
physical systems couple to scale, could improve our understanding of
naturalness problems caused by the disparity between the particle physics and
observed, cosmological constants. We further give some ideas how an ambient
description of tractor calculus could lead to a Ricci-flat/CFT correspondence
which generalizes the AdS side of Maldacena's duality to a Ricci-flat space of
one higher dimension.Comment: 20 pages, 2 figure
Spontaneous coronary artery dissection presenting as an ischaemic stroke in a middle-aged man with anti-cardiolipin antibodies: a case report
<p>Abstract</p> <p>Introduction</p> <p>Cerebrovascular disease is a major cause of mortality and morbidity worldwide. Ischemic stroke is the most common manifestation, encompassing a wide variety of causative mechanisms. We present the case of a middle-aged male patient with spontaneous coronary artery dissection in the presence of anti-cardiolipin antibodies, leading to left ventricular thrombus and presenting with stroke.</p> <p>Case presentation</p> <p>A 56-year-old Caucasian man presented with dysarthria and right-sided weakness. There was a history of chest pain with autonomic symptoms four days earlier. Examination revealed right-sided hemiparesis. Electrocardiogram showed sinus rhythm with anterior Q waves. Magnetic resonance imaging of the brain showed large left parietal and smaller multiple cerebral infarcts. Echocardiogram showed anterior wall and apical akinesis with a large mural thrombus. Anti-cardiolipin antibodies immunoglobulin G and immunoglobulin M were strongly positive. Coronary angiography showed dissection of the mid left anterior descending artery with normal flow down the distal vessel. He was treated conservatively with anticoagulation and secondary prevention. He was in good health when seen in clinic four months later.</p> <p>Conclusion</p> <p>We highlight the importance of a comprehensive approach at obtaining the correct diagnosis, input of different specialities and the fact that the presence of anti-cardiolipin antibodies is associated with coronary artery dissection in a middle-aged male patient whose presentation was stroke.</p
Modeling and Simulation of PV Panel Under Different Internal and Environmental Conditions with Non-constant Load
This paper focuses on PV power conversion under different internal and environmental conditions with non-constant load, connected to a smart grid system. Due to environmental conditions, the PV system is a non-linear system and difficult to predict the power conversion. In the aspect of internal variables, it includes the five parameters of the single diode solar cell model identify their sensitivity through error function. It also identifies the relation between environmental conditions, mainly: irradiance, temperature and wind speed. The modeling and computational simulation with laboratory work identify the effects of internal and environmental effect on the system. The model gives details about the sensitivity of each environmental condition using error function. The work includes the decrease of energy conversion by the solar panel as a function of time due to the shadow effect that affects its performance. Besides these, a smart system is introduced as a DAQ system in laboratory environment to get in real time the power conversion value with the P-V and I-V characteristics of the PV panel
The effects of remote ischaemic preconditioning on coronary artery function in patients with stable coronary artery disease
Background: Remote ischaemic preconditioning (RIPC) is a cardioprotective intervention invoking intermittent
periods of ischaemia in a tissue or organ remote from the heart. The mechanisms of this effect are incompletely
understood. We hypothesised that RIPC might enhance coronary vasodilatation by an endothelium-dependent
mechanism.
Methods: We performed a prospective, randomised, sham-controlled, blinded clinical trial. Patients with stable
coronary artery disease (CAD) undergoing elective invasive management were prospectively enrolled,
and randomised to RIPC or sham (1:1) prior to angiography. Endothelial-dependent vasodilator function
was assessed in a non-target coronary artery with intracoronary infusion of incremental acetylcholine doses
(10−6
, 10−5
, 10−4 mol/l). Venous blood was sampled pre- and post-RIPC or sham, and analysed for circulating
markers of endothelial function. Coronary luminal diameter was assessed by quantitative coronary angiography.
The primary outcome was the between-group difference in the mean percentage change in coronary luminal diameter
following the maximal acetylcholine dose (Clinicaltrials.gov identifier: NCT02666235).
Results: 75 patients were enrolled. Following angiography, 60 patients (mean ± SD age 57.5 ± 8.5 years; 80%
male) were eligible and completed the protocol (n = 30 RIPC, n = 30 sham). The mean percentage change in
coronary luminal diameter was −13.3 ± 22.3% and −2.0 ± 17.2% in the sham and RIPC groups respectively
(difference 11.32%, 95%CI: 1.2– 21.4, p = 0.032). This remained significant when age and sex were included as
covariates (difference 11.01%, 95%CI: 1.01– 21.0, p = 0.035). There were no between-group differences in
endothelial-independent vasodilation, ECG parameters or circulating markers of endothelial function.
Conclusions: RIPC attenuates the extent of vasoconstriction induced by intracoronary acetylcholine infusion. This
endothelium-dependent mechanism may contribute to the cardioprotective effects of RIP
Hospitalization for heart disease, stroke, and diabetes mellitus among Indian-born persons: a small area analysis
BACKGROUND: We set out to describe the risk of hospitalization from heart disease, stroke, and diabetes among persons born in India, all foreign-born persons, and U.S.-born persons residing in New York City. METHODS: We examined billing records of 1,083,817 persons hospitalized in New York City during the year 2000. The zip code of each patient's residence was linked to corresponding data from the 2000 U.S. Census to obtain covariates not present in the billing records. Using logistic models, we evaluated the risk of hospitalization for heart disease, stroke and diabetes by country of origin. RESULTS: After controlling for covariates, Indian-born persons are at similar risk of hospitalization for heart disease (RR = 1.02, 95% confidence interval 1.02, 1.03), stroke (RR = 1.00, 95% confidence interval, 0.99, 1.01), and diabetes mellitus (RR = 0.96 95% confidence interval 0.94, 0.97) as native-born persons. However, Indian-born persons are more likely to be hospitalized for these diseases than other foreign-born persons. For instance, the risk of hospitalization for heart disease among foreign-born persons is 0.70 (95% confidence interval 0.67, 0.72) and the risk of hospitalization for diabetes is 0.39 (95% confidence interval 0.37, 0.42) relative to native-born persons. CONCLUSIONS: South Asians have considerably lower rates of hospitalization in New York than reported in countries with national health systems. Access may play a role. Clinicians working in immigrant settings should nonetheless maintain a higher vigilance for these conditions among Indian-born persons than among other foreign-born populations
Soil application of Bacillus thuringiensis Berliner isolates against root-knot nematode (Meloidogyne javanica (Treub) Chitwood) in okra (Abelmoschus esculentus (L.) Moench)
Bacillus thuringiensis (B.t) is well known for its biocontrol potential against a variety of insects. Nematicidal potential of ten B.t isolates was tested against root-knot nematodes (Meloidogyne javanica (Treub) Chitwood) in vitro, under greenhouse as well as in field conditions. Eggs and second stage juveniles (J2) were exposed to 5 and 25% concentrations of bacterial cell-free aqueous extracts up to 96 h. B.t isolates showed lesser degrees of nematicidal activity at 5% concentration. However, some B.t isolates (B.t-14, B.t-16 and B.t-64) greatly reduced egg hatching and increased J2. All B.t isolates revealed suppressed egg hatching and increased mortality of J2 at 25% concentration. Soil applications with most of the B.t isolates under greenhouse and field conditions significantly improved height and fresh weights of root-knot nematode parasitized okra (Abelmoschus esculentus (L.) Moench). Some isolates, including B.t-64 reduced the number of galls and egg masses. B.t-64 reduced gall formation up to 70% under greenhouse conditions. However, 29% of decrease was observed in field conditions. Similarly, B.t-64 treated plants showed a 56% decreased in eggs/egg mass in a field experiment. Population of root-knot nematodes in the rhizosphere was decreased up to 61% in the field experiment as compared to control
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