36,759 research outputs found
Hardware synthesis from DDL description
The details of digital systems can be conveniently input into the design automation system by means of hardware description language (HDL). The computer aided design and test (CADAT) system at NASA MSFC is used for the LSI design. The digital design language (DDL) was selected as HDL for the CADAT System. DDL translator output can be used for the hardware implementation of the digital design. Problems of selecting the standard cells from the CADAT standard cell library to realize the logic implied by the DDL description of the system are addressed
Takotsubo Syndrome and COVID-19: Associations and Implications.
Incidence of cardiovascular complications has increased during the COVID-19 (Coronavirus disease 2019) pandemic, both population-wide and in patients diagnosed with the disease. This increase has presented complications in patient care, leading to increased hospitalizations, adverse outcomes, and medical costs. A condition of interest is takotsubo syndrome, which may be associated with the novel coronavirus. To understand this connection, a narrative review was performed by analyzing primary studies and case reports available. The findings showed increased incidence of takotsubo cardiomyopathy in both the general population and COVID-19 patients. Proposed mechanisms for the linkage include generalized increases in psychological distress, the cytokine storm, increased sympathetic responses in COVID-19 patients, and microvascular dysfunction. Moreover, natural disasters are noted as likely being associated with increases of takotsubo syndrome. As the pandemic continues, treating COVID-19 as a systemic condition is imperative, with the increase in takotsubo syndrome marking a significant impact of the novel coronavirus
Cataract How Important Is Age of Intervention?
Purpose: To study effect of age of intervention on visual outcome following treatment of pediatric patients with cataract.
Setting: Tertiary eye care centre in Dahod at the trijunction of Gujarat, Madhya Pradesh, and Rajasthan states in central western India.
Participants: 705 eyes of 1047 patients
Methods: This is a prospective cohort study. We studied a consecutive series of pediatric patients with congenital, developing, or COMPLICATED
cataracts who underwent surgery between January, 1999 and April, 2012 at our center. Patient demographics, cataract type, presenting symptoms, surgical intervention, postoperative visual acuity, and follow-up refractive changes were recorded.
Primary Outcome measures: vision.
Results: In total, 1305 eyes of 1047 children were included: unilateral cataracts were present in 786 (60.2%) eyes. There were 600 (46.7%) traumatic and 705 (53.3%) non-traumatic cases. Ages at surgery ranged from 1 to 215 months. Eyes were grouped by the age of surgical intervention performed: Group 1,</= 5 years including 177 (25.1%) eyes, and Group 2, >5 years, including 528 (74.9%) eyes either by anterior or pars plana route ± IOL placement. The mean follow-up time was 117 days. Ultimately, 128 (18.2%) Group 1 and 213 (30.2%)
Group 2 patients achieved a visual acuity better than 20/80 (P < 0.001). Age at intervention was significantly related (all P < 0.001) to visual outcome.
Conclusions: Age of intervention affects visual outcome significantly (p<0.001)
The second coefficient of a function with all derivatives univalent
We consider the second coefficient of a class of functions, univalent and normalized, and with all derivatives univalent in the unit disk D, and improve on a known result. It is also shown that this bound is in a sense best possible
Covert Ephemeral Communication in Named Data Networking
In the last decade, there has been a growing realization that the current
Internet Protocol is reaching the limits of its senescence. This has prompted
several research efforts that aim to design potential next-generation Internet
architectures. Named Data Networking (NDN), an instantiation of the
content-centric approach to networking, is one such effort. In contrast with
IP, NDN routers maintain a significant amount of user-driven state. In this
paper we investigate how to use this state for covert ephemeral communication
(CEC). CEC allows two or more parties to covertly exchange ephemeral messages,
i.e., messages that become unavailable after a certain amount of time. Our
techniques rely only on network-layer, rather than application-layer, services.
This makes our protocols robust, and communication difficult to uncover. We
show that users can build high-bandwidth CECs exploiting features unique to
NDN: in-network caches, routers' forwarding state and name matching rules. We
assess feasibility and performance of proposed cover channels using a local
setup and the official NDN testbed
Transient terahertz spectroscopy of excitons and unbound carriers in quasi two-dimensional electron-hole gases
We report a comprehensive experimental study and detailed model analysis of
the terahertz dielectric response and density kinetics of excitons and unbound
electron-hole pairs in GaAs quantum wells. A compact expression is given, in
absolute units, for the complex-valued terahertz dielectric function of
intra-excitonic transitions between the 1s and higher-energy exciton and
continuum levels. It closely describes the terahertz spectra of resonantly
generated excitons. Exciton ionization and formation are further explored,
where the terahertz response exhibits both intra-excitonic and Drude features.
Utilizing a two-component dielectric function, we derive the underlying exciton
and unbound pair densities. In the ionized state, excellent agreement is found
with the Saha thermodynamic equilibrium, which provides experimental
verification of the two-component analysis and density scaling. During exciton
formation, in turn, the pair kinetics is quantitatively described by a Saha
equilibrium that follows the carrier cooling dynamics. The terahertz-derived
kinetics is, moreover, consistent with time-resolved luminescence measured for
comparison. Our study establishes a basis for tracking pair densities via
transient terahertz spectroscopy of photoexcited quasi-two-dimensional
electron-hole gases.Comment: 14 pages, 8 figures, final versio
Influence of nitrogen flow rate in reducing tin microdroplets on biomedical TI-13ZR-13NB alloy
Cathodic arc physical vapor deposition (CAPVD) is one of the promising techniques that have a potential to coat titanium nitride (TiN) on biomedical implants due to its good adhesion and high evaporation rate. However, this method emits microdroplets which have the possible detrimental effect on the coating performance. Past studies indicated that micro droplets can be controlled through proper deposition parameters. In the present work, an attempt was made to study the effect of nitrogen gas flow rates (100 to 300 sccm) on TiN coating of the Ti-13Zr-13Nb biomedical alloy. Scanning electron microscopy (SEM) was used to evaluate surface morphology and coating thickness while crystal phase of the coated substrates was determined using X-Ray Diffraction (XRD). Image analysis software was employed to quantify microdroplets counts. Results show that higher nitrogen gas flow rate able to decrease a significant amount of microdroplets and concurrently increase the thickness of TiN coating. A mixed crystal planes of (111) and (220) are obtained on the coated substrates at this setting which exhibits denser structure with higher adhesion strength as compared to substrates coated at the lower N2 gas flow rate
Sustained remission in a case of lupus nephritis with cyclosporin therapy
Systemic lupus erythematosus (SLE) in severe form still presents a major therapeutic challenge. Aggressive treatment of severe renal lesions has improved the prognosis of renal disease over the last decade. However, this benefit is quite frequently offset by the side effects and toxicity of the treatment. Moreover, the disease may appear to be poorly responsive to treatment with steroids and cytotoxic drugs. We report a case of lupus nephritis that relapsed despite having adequate steroid and cytotoxic therapy, but later was successfully treated with cyclosporin. Fifteen months after discontinuing the treatment with cyclosporin, the patient continued to remain in remission
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