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We demonstrate a novel process for building a Resistive RAM (ReRAM) stack which reduces the forming voltage (Vform) and increases the switching resistance, both characteristics that are important ingredients for the use of ReRAM in scalable analog compute for AI. Utilizing this process, we explore analog switching characteristics above 100k Ω and demonstrate 4-bit programming at Rmax = 1MΩ. Utilizing the same writing characteristics, CIFAR-10 inference simulation shows 90% accuracy, comparable to the full precision model accuracy. [ABSTRACT FROM AUTHOR]

We have studied the oxidation of Si nanocrystals as a function of oxidizing ambient, temperature, time, and initial nanocrystal size using x-ray photoelectron spectroscopy, transmission electron microscopy, and energy-filtered transmission electron microscopy. Thicker oxide shells are obtained by oxidation in O[sub 2] ambient compared with NO ambient. Oxidation in O[sub 2] is observed to be self-limiting at temperatures below the viscoelastic temperature of SiO[sub 2] because of compressive stress normal to the SiO[sub 2]/Si interface, which retards the surface oxidation rate. Oxidation in NO also results in self-limiting oxidation due to the incorporation of N at the Si/SiO[sub x] interface. This N-rich interfacial layer acts as an effective barrier against oxidant diffusion and also blocks the reaction sites on the Si surface. Therefore, NO oxidation is successful in slowing further oxidation of Si cores, even in a severe oxidizing ambient such as O[sub 2] at 1050 °C. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

AIMS: This study aims to determine the sensitivity and specificity of vision screening by school teachers among primary school children. SETTINGS AND DESIGN: Prospective nonrandomized clinical trial. SUBJECTS AND METHODS: The study was carried in primary school children of Madurai, Tamil Nadu from April 2007 to October 2007. Sixty-five primary school teachers from 57 schools around Madurai, Tamil Nadu, India, underwent a half-day training programme at the hospital. Each teacher on return to the school screened around a hundred children using the tumbling E. All screened children were subsequently screened by a team from the hospital. The optometrists used tumbling E (Snellen's 20/30 and Early Treatment of Diabetic Retinopathy Study (ETDRS) 20/32) to check the vision of all children. Any child complaining of defective vision or noted to have defective vision on screening underwent a comprehensive ophthalmic evaluation. The sensitivity and specificity of teacher screening was assessed based on the data obtained. RESULTS: Screening was completed for 5150 children. The prevalence of vision <20/30 was 2.82%. Teacher screening was noted to have a sensitivity of 24.8% and a specificity of 98.65%. Tumbling E ETDRS screening by the optometrist had the highest sensitivity of 94.48% and specificity of 97.09%. CONCLUSIONS: Our study shows that vision screening by trained optometrists is a very useful tool to identify visual impairment in primary school children. Measures need to be taken to improve the sensitivity of teacher screening before recommending its generalized use. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this article is to study the feasibility of a delayed adjustable technique of strabismus surgery in children using an optional adjustable suture technique.Methods: The retrospective study included patients <12 years of age. Recessions were done using an optional adjustable bow-tie technique and resections were done by the conventional technique. Patients were evaluated on the third postoperative day and adjustments done when needed. Statistical analysis was done using Microsoft Excel 2010®.Results: The study included 11 patients with exotropia and 16 patients with esotropia. The mean age of the patients was 5.2 years (range 1-11 years). The mean preoperative distance deviation was 46.7 ± 10.4 prism diopters (PD) for exotropic patients and 47.1 ± 16.9 PD for esotropic patients. The mean preoperative near deviation was 46.6 ± 11 PD for exotropic patients and 52.4 ± 17.1 PD for esotropia. Two patients with exotropia (18.2%) and four patients with esotropia (25%) were adjusted under intravenous ketamine in the operating room under anesthetist supervision. No difficulty was encountered in advancing/recessing the muscles. The success rate at 1 month was 100% for exotropia and 87.5% for esotropia. The success rate at the final follow-up was 81.8% for patients with exotropia and 68.7% for patients with esotropia.Conclusions: This delayed optional adjustable strabismus surgery technique provides good short-term results and lower adjustment rates. [ABSTRACT FROM AUTHOR]

The concepts underlying a theoretical treatment of the vibrational energy relaxation (VER) time T1 of a solute normal mode in a molecular solvent are summarized, and results for T1, valid for VER processes mediated by vibrational–translational–rotational energy transfer, obtained from this treatment are presented. These results are based on the formula T1=βTR-1(ωl), where βTR(ω) is the translational–rotational branch of the friction kernel of the normal mode and where ωl is its liquid phase frequency. βTR(ω) is evaluated as the cosine transform of the autocorrelation function 〈F(t)F〉0 of the fluctuating generalized force exerted by the solvent on the solute normal mode coordinate conditional that this coordinate is fixed at its equilibrium value and that all solvent molecules are constrained to have their equilibrium geometries. The Gaussian model is utilized to evaluate 〈FF(t)F〉0 and molecular level expressions for ωl and for the Gaussian model parameters are presented for the infinitely dilute diatomic solution. The expressions involve site density integrals over the coordinates of a single solvent atomic site and over the coordinates of a pair of solvent atomic sites located on the same molecule. The results permit the evaluation of T1 in terms of the atomic masses and gas phase bondlengths of the solute and the solvent molecules, the solute gas phase vibrational frequency, the solute–solvent site–site interaction potentials, and specified equilibrium site–site pair correlation functions of the liquid solution. [ABSTRACT FROM AUTHOR]

A theoretical treatment of the vibrational–vibrational (VV) contribution to the vibrational energy relaxation time T1 of a solute normal mode in a molecular solvent, which extends a previous treatment [S. A. Adelman, R. H. Stote, and R. Muralidhar, J. Chem. Phys. 99, 1320 (1993), henceforth called Paper I] of the vibrational–translational–rotational (VTR) contribution to T1, is outlined and expressions for this VV contribution, valid for the infinitely dilute diatomic solution, are presented. The treatment is based on the formula T1=β-1(ωl), where β(ω) is the friction kernel of the relaxing solute mode and where ωl is its liquid phase frequency. β(ω) is evaluated as the cosine transform of the autocorrelation function 〈F(t)Fĩ〉0v of the fluctuating generalized force exerted by the vibrating solvent on the solute normal mode coordinate conditional that this coordinate is fixed at its equilibrium value. 〈F(t)F〉0v is expressed as a superposition of the rigid solvent autocorrelation function 〈F(t)F〉0 and a correction which accounts for solvent vibrational motion. For diatomic solvents one has 〈F(t)F〉0v= 〈F(t)F〉0+NSMD(t) cos ωDt F(ΩD), where NS=number of solvent molecules, MD(t) is the vibrational force gradient autocorrelation function, ωD and ΩD are solvent molecule liquid phase frequencies, and F(Ω)=1/2hΩ-1 coth[hΩ/2kBT].The Gaussian model is assumed for 〈F(t)F〉0 and MD(t) yielding β(ω) as a superposition of a Gaussian centered at ω=0 which mediates VTR processes and a Gaussian centered at ω=ωD which mediates VV processes. Vector integral expressions for MD(t), ωD, and ΩD are presented which are similar to the expressions for ωl and 〈F(t)F〉0 given in Paper I. These expressions permit the evaluation of the VV contribution to T1 from the atomic masses, bondlengths, vibrational frequencies, and site–site interaction... [ABSTRACT FROM AUTHOR]

A refined version of a molecular theory of liquid phase vibrational energy relaxation (VER) [S. A. Adelman and R. H. Stote, J. Chem. Phys. 88, 4397, 4415 (1988)] is presented and compared to the isolated binary collision (IBC) model. The theory is based on the Gaussian model for the fluctuating force autocorrelation function of the solute vibrational coordinate. Within the Gaussian model, the VER rate constant may be constructed in terms of solute–solvent site–site potential energy and equilibrium pair correlation functions. In the present refined treatment, crossfrictional contributions to the fluctuating force autocorrelation function are retained and its initial value 0 is evaluated from an exact rather than an approximate formula. Applications of the theory are made to model Lennard-Jones systems designed to simulate molecular iodine dissolved in liquid xenon at T=298 K and molecular bromine dissolved in liquid argon at T=295 K and T=1500 K. The refinements, along with an improved polynomial fitting procedure for the solute–solvent pair correlation functions, are found to yield significant changes in both the absolute VER rates and in their isothermal density dependencies.Moreover, it is found for all three solutions that the Gaussian decay time is nearly independent of density from ideal gas to the dense fluid regimes. This condition is sufficient for the emergence of an IBC-like factorization of the VER rate constant kliq(T) into a liquid phase structural contribution proportional to 〈F2>0 and a dynamical contribution which is nearly density independent. The liquid structural contribution is, in general, not well-approximated by a contact collisional assumption but rather depends on a range of solute–solvent interatomic separations. For the Br2/Ar solutions, the rate constant isotherms show a superlinear deviation from the low density extrapolation kliq(T)[bar_over_tilde:_approx._equal_to]ρ0kgas(T)... [ABSTRACT FROM AUTHOR]

This paper gives a theoretical treatment of liquid-phase activated barrier crossing that is valid for chemical reactions which occur on typical (e.g., high activation barrier) potential-energy surfaces. This treatment is based on our general approach [S. A. Adelman, Adv. Chem. Phys. 53, 61 (1983)] to problems in liquid-phase chemical dynamics. We focus on the early-time regime [times short compared to the relaxation time of 0, the fluctuating force autocorrelation function of the reaction coordinate] in which the solvent is nearly ‘‘frozen.’’ This regime has been shown to be important for the determination of the rate constant in the molecular-dynamics simulations of model aqueous SN2 reactions due to Wilson and co-workers. Our treatment is based on a generalized Langevin equation of motion which naturally represents the physics of the early-time regime.In this regime the main features of the reaction dynamics are governed by the instantaneous potential WIP[y,F], which accounts for the cage confinement forces which dominate the liquid-phase effects at early times, rather than by the familiar potential of mean force. The instantaneous potential is derived from the t→0 limit of the equation of motion and its properties are developed for both symmetric and nonsymmetric reactions. The potential is then shown to account for both the early-time barrier recrossing processes found to determine the transmission coefficient κ in the SN2 simulations and the dependence of these processes on environmental fluctuations modeled by F. Making the parabolic approximation for the gas-phase part of WIP[y,F] yields the following result for the transmission coefficient: κ=ω-1PMFx+=ω-1PMFωMIP[1+ω-2 MIPΘ(x+)]1/2≠ ω-1PMFω MIP[1+ (1)/(2) ω-2MIPΘ(ωMIP)], where ωMIP and ωPMF are, respectively, the barrier frequencies of WIP[y,F=0] and of the potential of mean force, and... [ABSTRACT FROM AUTHOR]

IntroductionA number of ocular complications have been reported in microspherophakia. The literature however is limited to small case reports and the incidence of these complications is largely unknown. Our study describes a series of patients who presented to our hospital from 1998 to 2008.Material and methodsData on the clinical and surgical findings of patients presented to us from 1998 to 2008 with microspherophakia were retrieved from the medical records and the results analyzed.ResultsThirty-six eyes of 18 patients were reviewed. The mean age at presentation was 16±10 years. All patients had varying degrees of lenticular myopia with a mean of −11.07±5.03 D. Glaucoma developed in 16 eyes (44.4%). Half of them had high IOP at presentation. Despite medical and surgical management IOP remained high in five eyes at the last follow-up. Sixteen eyes (44.4%) required lensectomy for dislocated crystalline lens. Lensectomy did not have any impact on the intraocular pressures. Homocysteinuria was the most common systemic association noted.ConclusionMicrospherophakia is associated with a high incidence of lenticular myopia, subluxation of the crystalline lens and glaucoma. Management of glaucoma is difficult with the IOP remaining high in spite of combined medical and surgical management. [ABSTRACT FROM AUTHOR]

To understand the response of oral epithelial cells, transplanted on corneal surface to the ocular cues in vivo. The corneal button obtained after penetrating keratoplasty (PK) of an eye of a patient with total limbal stem cell deficiency (LSCD), previously treated with cultured oral mucosal epithelial transplantation (COMET) was examined by immunohistochemistry for the expression of keratins, p63, p75, PAX6, Ki-67, CD31, and CD34. COMET followed by optical-PK has improved visual acuity to 20/40 and rendered a stable ocular surface. The excised corneal tissue showed the presence of stratified epithelium with vasculatures. The epithelial cells of the corneal button expressed K3, K19, Ki-67, p63, p75 and the cornea-specific PAX6 and K12. This study confirms that the oral cells, transplanted to corneal surface, survive and stably reconstruct the ocular surface. They maintain their stemness at the ectopic site and acquire some of the corneal epithelial-like characters. [ABSTRACT FROM AUTHOR]

Orthodontic anterior intrusion for correcting deep bites often constitutes an integral part of orthodontic treatment in order to improve sagittal and vertical incisor relationships, in cases of pseudo-deep overbite, where the anteriors are supraerrupted true intrusion of the incisors is indicated and also in patients with gummy smiles and periodontal compromised teeth to correct the gingival line and restore the esthetics of smile. Intrusion is mainely achived by use of verious loop mechnices or implant mechanics or differiantial force concept given by beggs.In this artical different mechanics for intrusion in beggs technique and PEA technique are mentioned. [ABSTRACT FROM AUTHOR]

Strabismus is a well recognized complication of retrobulbar anesthesia for cataract surgery. This may manifest as either paresis or sometimes contracture (overaction) in the late stage. Management of the patient is tailored to the individual case. Herein, we report a patient with inferior rectus paresis and medial rectus overaction after retrobulbar anesthesia. The presenting symptom was diplopia increasing on downgaze, which improved with medial rectus recession and plication of the inferior rectus. [ABSTRACT FROM AUTHOR]

We describe a patient with situational restriction of elevation in adduction in his left eye. Clinical examination pointed to instability of the left medial rectus pulley. This was corrected by Faden on the medial rectus. The importance of this relatively new concept in identifying and treating orbital pulley instability is discussed. [ABSTRACT FROM AUTHOR]

The authors present a case of optic nerve cysticercosis in a 32-year-old patient who presented with sudden blurring of vision in the left eye and a transient visual improvement on systemic steroids. The ocular findings were unremarkable other than a relative afferent pupillary defect (RAPD). An ultrasound of the orbit, CT and MRI scans revealed a cystic lesion in the orbital portion of the optic nerve close to the eyeball. A presumed diagnosis of optic nerve cysticercosis was made on the basis of imaging and a positive serum ELISA. The patient improved dramatically on a 4-week therapeutic trial of albendazole and oral steroids. The post-treatment ultrasound and CT scan showed an involution of the cyst with some residual thickening of the optic nerve. [ABSTRACT FROM AUTHOR]

This paper introduces a silicon nanocrystal-silicon nitride hybrid single transistor cell for potential dynamic RAM (DRAM) applications that stores charge in silicon nanocrystals or a silicon nitride charge trapping layer or both. The memory operates in the direct tunneling regime for the tunnel oxide and so presents the possibility of a DRAM with good cycling endurance. The silicon nanocrystals of this hybrid device present intermediate states that facilitate tunneling transport to and from the nitride layer. Short time measurements show that the hybrid silicon nanocrystal silicon nitride based DRAM cell programs and erases much faster than a plain SONOS implementation while offering better data retention, memory signal and longer refresh time than a silicon nanocrystal type DRAM. [ABSTRACT FROM PUBLISHER]

This paper presents the design, implementation, and deployment of the DISCOVER Web-based computational collaboratory. Its primary goal is to bring large distributed simulations to the scientists'/engineers' desktop by providing collaborative Web-based portals for monitoring, interaction and control. DISCOVER supports a three-tier architecture composed of detachable thin-clients at the front-end, a network of interaction servers in the middle, and a control network of sensors, actuators, and interaction agents at the back-end. The interaction servers enable clients to connect and collaboratively interact with registered applications using a browser. The application control network enables sensors and actuators to be encapsulated within, and directly deployed with the computational objects. The application interaction gateway manages overall interaction. It uses Java Native Interface to create Java proxies that mirror computational objects and allow them to be directly accessed at the interaction server. Security and authentication are provided using customizable access control lists and SSL-based secure servers. Copyright © 2001 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Monoclonal antibodies are monospecific antibodies. They are generated also by hybridoma technology. They are useful in target specific therapy against dangerous diseases. This property of monoclonal antibody offers us a new hope to combat deadly diseases where chemotherapy fails to produce specific treatment without adverse effects. This review article deals with the use of monoclonal antibodies specific against tumors and viral infections. [ABSTRACT FROM AUTHOR]

Griseofulvin is an antifungal antibiotic used to treat various pathogenic mycotic diseases of animals and plants. Various analytical techniques for the determination of griseofulvin in pure form, in different chemical mixtures, in biological fluids and in fermentation samples are described in this review. The present communication reviews the use of spectrophotometry, spectrofluorimetry, paper chromatography, thin layer chromatography, gas chromatography, high performance liquid chromatography and microbiological assay for the estimation of griseofulvin. [ABSTRACT FROM AUTHOR]

Human placenta is a rich source of many biological products. It is an economical source as it is easily available as a hospital waste. The products obtained from human placenta include enzymes, genetic material, cellular proteins and antibodies. Some classes of enzymes which are not available after parturition or which cannot be obtained from the human body can be obtained from placenta. This article reviews various placental products including their extraction and purification. [ABSTRACT FROM AUTHOR]

A major aspect of describing transport in heterogeneous media has been that of relating effective diffusivities to the topological properties of the medium. While such effective transport coefficients may be useful for mass fractals or under steady state conditions, they are not adequate under transient conditions for self-similar pore fractal media. In porous formations without scale, diffusion is anomalous with the mean-squared displacement of a particle proportional to time raised to a fractional exponent less than unity. The objective of this review is to investigate the nature of the laws of diffusion in fractal media using the framework of linear response theory of nonequilibrium statistical mechanics. A Langevin/Fokker-Planck approach reveals that the particle diffusivity depends on its age defined as the time spent by the particle since its entry into the medium. An analysis via generalized hydrodynamics describes fractal diffusion with a frequency and wave number dependent diffusivity. [ABSTRACT FROM AUTHOR]

The pathological and clinical features of 17 cases of malignant lymphoma of testis seen at Tata Memorial Hospital, Bombay, from the year 1941 through 1972 are presented. Malignant lymphoma accounts for 3-8 % of 445 histologically proved cases of testicular malignancies in our material. The material has been divided into 3 groups: (i) Testicular tumour as the only manifestation throughout the course of the disease (3 cases); (ii) Testicular tumour followed by dissemination during the course of the disease (12 cases); (iii) Testicular tumour following generalised lymphoma (2 cases). Bilateral testicular tumours are rare but when they do occur malignant lymphoma accounts for the larger number of cases. Of 4 bilateral testicular tumours found in the total number of 445 testicular malignancies 3 belonged to malignant lymphoma group. The maximum number of patients (14) were between the ages of 40 and 68 years. Two cases of lymphoma occurred in patients aged 5 years and 16 years respectively. Malignant lymphoma of testis is a disease with a poor prognosis. The majority of the patients died within a year following orchidectomy. One patient is alive and free from disease for 5 years and 6 months after orchidectomy. Hodgkin's disease of the testis is very rarely reported. We have seen 2 cases in our material. [ABSTRACT FROM AUTHOR]

There is limited literature on the management of cataracts in juvenile xanthogranuloma (JXG). A 2-month-old girl presented to us with hyphema, secondary glaucoma OU and skin nodules suggestive of JXG. She developed bilateral cataracts during her follow-up and was treated successfully with cataract surgery and aphakic rehabilitation. [ABSTRACT FROM AUTHOR]

The short-channel effects (SCEs) of planar bulk and fully depleted finFET devices have been compared using the same junction overlap and lateral gradient, and it is shown that, for finFET devices, a significant component of electrostatic control arises from a naturally present shallow extension junction. When such shallow junctions are applied to a bulk device, we show that the SCE becomes comparable to that of a finFET. Furthermore, we show that, if an embedded source/drain stressor is incorporated in a bulk device, it will not degrade the short-channel benefit of the ultrashallow junctions. The ability to span a wide power/performance range by doping and the improvement in SCEs by the use of ultrashallow extension junctions can potentially extend the life of bulk-type technologies. [ABSTRACT FROM PUBLISHER]

Context: Pediatric cataract surgery is traditionally done with the aid of high-molecular-weight viscoelastics which are expensive. It needs to be determined if low-cost substitutes are just as successful. Aims: The study aims to determine the success rates for anterior and posterior capsulorrhexis and intraocular lens (IOL) implantation in the bag for pediatric cataract surgery performed with the aid of a low-molecular-weight viscoelastic. Settings and Design: Nonrandomized observational study. Materials and Methods: Children less than 6 years of age who underwent cataract surgery with IOL implantation in the period May 2008-May 2009 were included. The surgeries were done by pediatric ophthalmology fellows. A standard procedure of anterior capsulorrhexis, lens aspiration with primary posterior capsulorrhexis, anterior vitrectomy, and IOL implantation was followed. Three parameters were studied: successful completion of anterior and posterior capsulorrhexis and IOL implantation in the bag. Results: 33 eyes of 28 children were studied. The success rate for completion was 66.7% and 88.2 % for anterior and posterior capsulorrhexis, respectively. IOL implantation in the bag was successful in 87.9%. Conclusions: 2% hydroxypropylmethylcellulose is a viable low-cost alternative to more expensive options similar to high-molecular-weight viscoelastics. This is of great relevance to hospitals in developing countries. [ABSTRACT FROM AUTHOR]

Lipoid proteinosis is a rare disorder involving multiple organ systems. The ocular manifestations are usually trivial, but greatly aid in the diagnosis. We describe a patient who presented to us with typical moniliform blepharosis. A brief description of relevance to the ophthalmologist and review of the literature follows. [ABSTRACT FROM AUTHOR]

Osler-Weber-Rendu syndrome, also known as hereditary hemorrhagic telangiectasia, is a rare autosomal dominant disorder manifested by telangiectases of the skin and mucous membranes and arteriovenous malformations of various organ systems. We present a case of Osler-Weber-Rendu syndrome with 11 affected members in her family. [ABSTRACT FROM AUTHOR]

Nucleation of dislocation loops from sharp corners playing the role of stress concentrators located on the surface of Si1-xGex strained layers is studied. The surface is of {100} type and the concentrator is oriented such as to increase the applied resolved shear stress in one of the {111} glide planes. The mean stress in the structure is controlled through the boundary conditions, independent of the Ge concentration. Shuffle dislocations are considered throughout, as appropriate for low temperature-high stress conditions. The effect of Ge atoms located in the glide plane, in the vicinity of the glide plane and at larger distances is studied separately. It is observed that Ge located in the glide plane leads to the reduction of the activation energy for dislocation nucleation. The activation volume in presence of Ge is identical to that in pure Si. Ge located in {111} planes three interplanar distances away from the active glide plane has little effect on nucleation parameters. The far-field Ge contributes through the compressive normal stress it produces and leads to a slight reduction of the activation energy for shuffle dislocation nucleation. [ABSTRACT FROM AUTHOR]

Protoplast fusion is a non-specific recombination technique used for transfer of cytosolic organelles including genetic material. The process involves cell wall breakdown, regeneration of protoplasts, chemofusion and electrofusion. This review article discusses all the stages involved in fusion of protoplasts and some of the applications of protoplast fusion technique in fungal systems. [ABSTRACT FROM AUTHOR]

Human placenta is a viable source of many useful products. Some of the products obtained are of use in health care industry. This review article deals with cosmetics, pharmaceuticals, blood products and hormone like substances obtained from human placenta. Various methods of their extraction, purification, characterization and their method of preparation have been discussed in detail. [ABSTRACT FROM AUTHOR]

Examines epitaxial trilayers of ytterbium barium copper oxide/neodymium aluminum oxide/ytterbium copper oxide grown on magnesium oxide substrates by pulsed laser deposition. Design, fabrication and testing of compact resonators; Variation in resonant frequencies of resonators; Measurement and simulation of resonant frequencies, insertion losses and quality factors.