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ABSTRACT In efforts to reduce the operation and maintenance cost of wind turbines, there is an increasing interest to monitor key turbine quantities such as the torque load on the gearbox. Monitoring the torque paves the way for the calculation of remaining useful lifetime, leading to cost reductions through improved reliability and maintenance planning. In order to avoid expensive direct torque sensors, this paper investigates the potential of virtual torque sensing, a technique based on 3 basic components: first, a set of non‐intrusive sensors installed on the gearbox. Three groups of strain gauges on the gearbox as well an angular encoder are considered in this paper. Second is a physics‐based model, capable of predicting the response of aforementioned sensors. These models are constructed with a purposeful balance between accuracy and computational cost. Model validation and updating are performed to ensure efficient and accurate prediction of the sensor output. Finally, an augmented extended Kalman filter (AEKF) is used to combine the measured response with predictions from the model to infer the gearbox input torque. Since a key factor determining the performance of the AEKF is the tuning of the AEKF covariance matrices, multiple methods are introduced to systematically tune the covariance matrices. Experimental validation results show that the virtual torque sensor can detect the load torque with a normalized mean absolute error (NMAE) between 3.41% and 7.47%, depending on the sensor set. The influence of the amount of sensors used and the tuning method are also investigated.

We investigate properties of optical elements in the optical cavity of an x-ray laser oscillator with emphasis on the power loss of a monochromatic Gaussian radiation beam upon passing through them using analytical and numerical approaches. Here we assume the optical cavity comprises of refractive lenses and Bragg crystals exploiting symmetric Bragg scattering. For the lens, we include focusing and curvature effects while we include angular filtering due to finite Darwin width of the Bragg crystal. Our results indicate the feasibility of x-ray power out-coupling in the range of 0.5%–28% with intracavity reflectivity of 67%–95% at 10.321 keV for nominal (≥65% reflectivity) cases. We also show the possibility of achieving high out-coupling of 35%–80% while restricting the intracavity reflectivity in the 19%–62% by adopting lossy cavities with 10–20 μm thin crystals.

The resolution of a mega-electron-volt scanning transmission electron microscope (MeV-STEM) is primarily governed by the properties of the incident electron beam and angular broadening effects that occur within thick biological samples and microchips. A precise understanding and mitigation of these constraints require detailed knowledge of beam emittance, aberrations in the STEM column optics, and energy-dependent elastic and inelastic critical angles of the materials being examined. This simulation study proposes a standardized experimental framework for comprehensively assessing beam intensity, divergence, and size at the sample exit. This framework aims to characterize electron-sample interactions, reconcile discrepancies among analytical models, and validate Monte Carlo (MC) simulations for enhanced predictive accuracy. Our numerical findings demonstrate that precise measurements of these parameters, especially angular broadening, are not only feasible but also essential for optimizing imaging resolution in thick biological samples and microchips. By utilizing an electron source with minimal emittance and tailored beam characteristics, along with amorphous ice and silicon samples as biological proxies and microchip materials, this research seeks to optimize electron beam energy by focusing on parameters to improve the resolution in MeV-STEM/TEM. This optimization is particularly crucial for in situ imaging of thick biological samples and for examining microchip defects with nanometer resolutions. Our ultimate goal is to develop a comprehensive mapping of the minimum electron energy required to achieve a nanoscale resolution, taking into account variations in sample thickness, composition, and imaging mode.

In this article, we summarize recent theoretical and experimental studies of the impedance and beam-induced heating of titanium-coated ceramic vacuum chambers used in the NSLS-II injection kickers. The impedance was calculated using the field matching theory assuming planar approximation and compared with the impedancewake2d code. For the coating thickness of a few microns, we demonstrated that the beam-induced power is dissipated in the titanium coating and that the longitudinally averaged two-dimensional power density is approximated by an analytical expression, thus allowing the use of a simplified model of the power density as input for the ansys code to simulate the temperature distribution with realistic nonuniform thickness of the Ti coating. For a few values of the NSLS-II beam current, we measured the beam-induced heating of two ceramic chambers using thermal sensors installed along the chamber and compared the measurement results with the simulations.

To align with the global trend of integrating synchrotron light source (SLS) and free electron laser (FEL) facilities on one site, in line with examples such as SPring-8 and SACLA in Japan and ELETTRA and FERMI in Italy, we actively explore FEL options leveraging the ultralow-emittance electron beam of the NSLS-II upgrade. These options show promising potential for synergy with storage ring (SR) operations, thereby significantly enhancing our facility’s capabilities. Echo-enabled harmonic generation (EEHG) is well-suited to SR-based FELs, and has already been demonstrated with the capability of generating extremely narrow bandwidth as well as high brightness, realized using diffraction-limited short pulses in transverse planes and Fourier transform-limited bandwidth in the soft X-ray spectrum. However, regarding a conventional EEHG scheme, the combination of the shortest seed laser wavelength (256 nm) and highest harmonic (200) sets the short wavelength limit to λ = 1.28 nm. To further extend the short wavelength limit down to the tender and hard X-ray region, a vital option is to shorten the seed laser wavelength. Thanks to recent advances in high harmonic generation (HHG), packing 109 photons at one harmonic within a few-femtosecond pulse could turn such a novel HHG source into an ideal seeding for EEHG. Thus, compared to the cascaded EEHG, the HHG seeding option could not only lower the cost, but also free the SR space for accommodating more user beamlines. Moreover, to mitigate the SASE background noise on the sample and detector, we combine the HHG seeding EEHG with the crab cavity short pulse scheme for maximum benefit.

To optimize electron energy for in situ imaging of large biological samples up to 10 μm in thickness with nanoscale resolutions, we implemented an analytical model based on elastic and inelastic characteristic angles. This model has been benchmarked by Monte Carlo simulations and can be used to predict the transverse beam size broadening as a function of electron energy while the probe beam traverses through the sample. As a result, the optimal choice of the electron beam energy can be realized. In addition, the impact of the dose-limited resolution was analysed. While the sample thickness is less than 10 μm, there exists an optimal electron beam energy below 10 MeV regarding a specific sample thickness. However, for samples thicker than 10 μm, the optimal beam energy is 10 MeV or higher depending on the sample thickness, and the ultimate resolution could become worse with the increase in the sample thickness. Moreover, a MeV-STEM column based on a two-stage lens system can be applied to reduce the beam size from one micron at aperture to one nanometre at the sample with the energy tuning range from 3 to 10 MeV. In conjunction with the state-of-the-art ultralow emittance electron source that we recently implemented, the maximum size of an electron beam when it traverses through an up to 10 μm thick bio-sample can be kept less than 10 nm. This is a critical step toward the in situ imaging of large, thick biological samples with nanometer resolution.

Driven by life-science applications, a mega-electron-volt Scanning Transmission Electron Microscope (MeV-STEM) has been proposed here to image thick frozen biological samples as a conventional Transmission Electron Microscope (TEM) may not be suitable to image samples thicker than 300–500 nm and various volume electron microscopy (EM) techniques either suffering from low resolution, or low speed. The high penetration of inelastic scattering signals of MeV electrons could make the MeV-STEM an appropriate microscope for biological samples as thick as 10 μm or more with a nanoscale resolution, considering the effect of electron energy, beam broadening, and low-dose limit on resolution. The best resolution is inversely related to the sample thickness and changes from 6 nm to 24 nm when the sample thickness increases from 1 μm to 10 μm. To achieve such a resolution in STEM, the imaging electrons must be focused on the specimen with a nm size and an mrad semi-convergence angle. This requires an electron beam emittance of a few picometers, which is ~1000 times smaller than the presently achieved nm emittance, in conjunction with less than 10−4 energy spread and 1 nA current. We numerically simulated two different approaches that are potentially applicable to build a compact MeV-STEM instrument: (1) DC (Direct Current) gun, aperture, superconducting radio-frequency (SRF) cavities, and STEM column; (2) SRF gun, aperture, SRF cavities, and STEM column. Beam dynamic simulations show promising results, which meet the needs of an MeV-STEM, a few-picometer emittance, less than 10−4 energy spread, and 0.1–1 nA current from both options. Also, we designed a compact STEM column based on permanent quadrupole quintuplet, not only to demagnify the beam size from 1 μm at the source point to 2 nm at the specimen but also to provide the freedom of changing the magnifications at the specimen and a scanning system to raster the electron beam across the sample with a step size of 2 nm and the repetition rate of 1 MHz. This makes it possible to build a compact MeV-STEM and use it to study thick, large-volume samples in cell biology.

Abstract To demonstrate the feasibility of automating UED operation and diagnosing the machine performance in real time, a two-stage machine learning (ML) model based on self-consistent start-to-end simulations has been implemented. This model will not only provide the machine parameters with adequate precision, toward the full automation of the UED instrument, but also make real-time electron beam information available as single-shot nondestructive diagnostics. Furthermore, based on a deep understanding of the root connection between the electron beam properties and the features of Bragg-diffraction patterns, we have applied the hidden symmetry as model constraints, successfully improving the accuracy of energy spread prediction by a factor of five and making the beam divergence prediction two times faster. The capability enabled by the global optimization via ML provides us with better opportunities for discoveries using near-parallel, bright, and ultrafast electron beams for single-shot imaging. It also enables directly visualizing the dynamics of defects and nanostructured materials, which is impossible using present electron-beam technologies.

У статті описано концептуальну модель адаптивного управління кіберзахистом інформаційно-освітнього середовища сучасного університету (ІОСУ). Мережі Петрі застосовано як математичний апарат для вирішення завдання адаптивного управління правами доступу користувачів ІОСУ. Запропоновано імітаційну модель та виконано моделювання у пакеті PIPE v4.3.0. Показано можливість автоматизації процедур коригування профілю користувача для мінімізації або нейтралізації кіберзагроз в ІОС. Запропоновано модель розподілу завдань користувача в комп'ютерних мережах ІОСУ. Модель, на відміну існуючих, побудована з урахуванням математичного апарату мереж Петрі і містить змінні, які дозволяють скоротити потужність простору станів. Доповнено метод контролю прав доступу (МКПД). Доповнення торкнулися аспектів перевірки прав доступу, які запитуються завданням та вимогами політики безпеки, ступенем узгодженості завдань та дозволених до доступу вузлів ІОСУ. Коригування правил та метрик безпеки для нових задач або перерозподілу задач описано в нотації мереж Петрі

Сучасний світ висуває високі вимоги до IT-інфраструктури та комп’ютерних мереж підприємств, що обумовлює складність їх структур. Чим складніша структура і кількість ланок, що входять до неї, тим вища імовірність появи вразливих місць. З бурхливим розвитком Інтернету широкого застосування набули веб–додатки. За їх допомогою відбувається взаємодія з клієнтами, надається доступ до важливої інформації. Відмовитися від веб-додатків дуже складно. Без них організація може втратити свою конкурентоспроможність або взагалі не зможе працювати. На фоні зростання популярності веб-додатків зростає і необхідність їх захисту від злому та несанкціонованого доступу, так як більше 75% атак хакерів спрямовані на вразливості веб-додатків та сайтів. Наслідки подібних зловмисних дій досить очевидні і не дуже приємні для компаній (в особливості їх клієнтів): втрата особистих даних, включаючи платіжну інформацію; можливість отримання доступу до комерційної таємниці та конфіденційних документів, крім того, вразливості веб-додатків можуть стати точкою входу зловмисників в корпоративну мережу. Традиційні методи мережевого захисту не запобігають атакам на веб-сервіси. Міжмережеві екрани орієнтовані на загрози мережевого і транспортного рівнів, в той час як веб-додатки працюють на прикладному рівні. Брандмауер веб-додатків (Web Application Firewall) - тип брандмауеру, який застосовується для захисту веб-додатків. У той час, як прямий проксі-сервер захищає ідентифікацію клієнтського комп’ютера за допомогою посередника, WAF розгортається перед веб-додатками (в режимі зворотного проксі-серверу) і аналізує двонаправлений трафік HTTP/HTTPS, виявляючи шкідливий трафік та блокуючи його. WAF не є остаточним рішенням безпеки, скоріше вони призначені для використання в поєднанні з іншими рішеннями безпеки периметра мережі, такими як брандмауери нового покоління (NGFW) та системами запобігання вторгнень (IPS).

Abstract To harness the full potential of the ultrafast electron diffraction (UED) and microscopy (UEM), we must know accurately the electron beam properties, such as emittance, energy spread, spatial-pointing jitter, and shot-to-shot energy fluctuation. Owing to the inherent fluctuations in UED/UEM instruments, obtaining such detailed knowledge requires real-time characterization of the beam properties for each electron bunch. While diagnostics of these properties exist, they are often invasive, and many of them cannot operate at a high repetition rate. Here, we present a technique to overcome such limitations. Employing a machine learning (ML) strategy, we can accurately predict electron beam properties for every shot using only parameters that are easily recorded at high repetition rate by the detector while the experiments are ongoing, by training a model on a small set of fully diagnosed bunches. Applying ML as real-time noninvasive diagnostics could enable some new capabilities, e.g., online optimization of the long-term stability and fine single-shot quality of the electron beam, filtering the events and making online corrections of the data for time-resolved UED, otherwise impossible. This opens the possibility of fully realizing the potential of high repetition rate UED and UEM for life science and condensed matter physics applications.

Викладено підходи до застосування методів системного аналізу для вирішення задач пов'язаних із забезпеченням інформаційної безпеки підприємств на транспорті, які відрізняються складною ІТ структурою з великою кількістю компонентів. Показано, що активне розширення областей інформатизації транспортної галузі, особливо в сегменті мобільних, розподілених і бездротових технологій, супроводжується появою нових загроз інформаційної безпеки. Показано, що для побудови ефективної системи інформаційної безпеки, вибору і впровадження адекватних технічних засобів захисту повинен передувати етап опису, аналізу та моделювання загроз, вразливостей, з подальшим розрахунком ризиків для ІБ і визначенням оптимальної стратегії розвитку системи інформаційної безпеки (СІБ). Після оцінки різних варіантів СІБ за декількома критеріями, приймається рішення: якщо рекомендації збігаються, то з більшою впевненістю обирається оптимальне рішення. Якщо спостерігається протиріччя висновків експертів, то остаточне рішення приймається з урахуванням його переваг і недоліків, наприклад, вибирається та стратегія розвитку системи інформаційної безпеки, яка виявилася оптимальною хоча б для двох критеріїв. Якщо отримані різні стратегії розвитку СІБ для всіх трьох критеріїв, то потрібно варіювати значеннями показника песимізму-оптимізму в критерії Гурвіца або змінити дані, наприклад, про можливі загрози для ІС або автоматизованої системи управління підприємства. Запропоновано алгоритм моделювання процесу прийняття рішення щодо вибору оптимальної стратегії управління інвестиційним проектуванням компонентами системи інформаційної безпеки для господарюючого суб'єкта на транспорті.

To analyze nonlinear dynamic systems, we developed a new technique based on the square matrix method. We propose this technique called the “convergence map” for generating particle stability diagrams similar to the frequency maps widely used in accelerator physics to estimate dynamic aperture. The convergence map provides similar information as the frequency map but in a much shorter computing time. The dynamic equation can be rewritten in terms of action-angle variables provided by the square matrix derived from the accelerator lattice. The convergence map is obtained by solving the exact nonlinear equation iteratively by the perturbation method using Fourier transform and studying convergence numerically. When the iteration is convergent, the solution is expressed as a quasiperiodic analytical function as a highly accurate approximation and hence the motion is stable. The border of stable motion determines the dynamical aperture. As an example, we applied the new method to the nonlinear optimization of the NSLS-II storage ring and demonstrated a dynamic aperture comparable to or larger than the nominal one obtained by particle tracking. The computation speed of the convergence map is 30 to 300 times faster than the speed of the particle tracking, depending on the size of the ring lattice (number of superperiods). The computation speed ratio is larger for complex lattices with low symmetry, such as particle colliders.

The coupled-bunch instability for arbitrary multibunch configurations is investigated in its generality. The theoretical framework adopted is based on the general eigenvalue analysis based on the known formulas of the complex frequency shifts for the uniform multibunch configuration case. Closed formulas are derived for special cases. For the configuration consisting of a uniform filling pattern with a gap of missing bunches, the theoretical results are found to be in good agreement with measurements of the transverse coupled-bunch instability driven by the resistive wall impedance performed at the NSLS-II storage ring.

A numerical method to design nonlinear double- and multibend achromat (DBA and MBA) lattices with approximate invariants of motion is investigated. The search for such nonlinear lattices is motivated by Fermilab’s Integrable Optics Test Accelerator, whose design is based on an integrable Hamiltonian system with two invariants of motion. While it may not be possible to design an achromatic lattice for a dedicated synchrotron light source storage ring with one or more exact invariants of motion, it is possible to tune the sextupoles and octupoles in existing double- and multibend achromat lattices to produce approximate invariants. In our procedure, the lattice is tuned while minimizing the turn-by-turn fluctuations of the Courant-Snyder actions J_{x} and J_{y} at several distinct amplitudes, while simultaneously minimizing diffusion of the on-energy betatron tunes. The resulting lattices share some important features with integrable ones, such as a large dynamic aperture, trajectories confined to invariant tori, robustness to resonances and errors, and a large amplitude-dependent tune spread. Compared to the nominal National Synchrotron Light Source-II lattice, the single- and multibunch instability thresholds are increased and the bunch-by-bunch feedback gain can be reduced.

As the next generation of light sources is pushing toward high-brightness storage rings with ultralow emittance, the control of the beam nonlinear dynamics becomes increasingly challenging. Nonlinear perturbations, arising from sextupole cross talks, set the limit to the achievable dynamic performance of the machine. Octupoles can be an efficient mean to tackle the remaining resonant driving terms generated to the second order by the lattice sextupoles. However, they have been used sparingly in light sources because of a lack of control on higher order effects. In this paper, we discuss the optimal positioning of octupoles, with respect to the sextupoles present in the lattice, for a local and simultaneous compensation of all fourth order on-momentum phase and amplitude dependent driving terms, using only three families of octupoles. In addition, higher order geometrical terms are also minimized, including among others, second-order tune shift with amplitude. This study is a continuation of past research made on the optimal use of octupoles for the operation of future light sources. The correction method was built on observations made on a simple model, then applied to a realistic low-emittance lattice, designed in the framework of the upgrade of the National Synchrotron Light Source II, to demonstrate its potential.

The resonant interaction of a bunched particle beam with short-range wakefields is the cause of head-tail instability, which is a major limitation for single-bunch beam intensity in circular accelerators. There are several processes that suppress this type of instability, such as fast chromatic damping and Landau damping due to machine nonlinearity. Beam-based feedback systems (transverse dampers) provide active suppression of the beam oscillations. The combined effect of the transverse dampers and chromaticity is discussed in this article. A brief overview of theoretical and experimental studies of the head-tail instability and its mitigation is presented. Results of experimental studies of the transverse mode coupling carried out at National Synchrotron Light Source-II are compared with the theoretical model.

Some aspects of education of specialists are reflected in the article. Methods and problems of organization of improvement of quality and efficiency of learning process are considered. The paper conducts a comparative analysis of the competencies that are formed at different levels of education according to Russian and European educational standards.

In this paper we evaluated the prospects for renewable energy, in order to meet the needs of agricultural facilities regions of Crimea. The current state of energy supply and the agro-industrial complex of Crimea are shown. Analyzed the potential for renewable energy in the agro-industrial regions of the Crimea. Given the prospects for renewable energy in order to meet the needs of agricultural facilities regions of Crimea.

NSLS-II is now one of the brightest synchrotron light sources worldwide, in user operations since 2014. Currently, 20 light-generating insertion devices (IDs) are installed: 3 damping wigglers and 17 undulators of various types. These devices introduce significant distortions into the magnet lattice of the storage ring. For each ID, the distortions have been locally corrected using quadrupole magnets located nearby the ID. The insertion devices have also a significant impact on the electron beam emittance. Precise measurements of the emittance were carried out at the Coherent Hard X-ray beamline for three different lattices: without IDs, with 3 pairs of damping wigglers only, and with all IDs. A minimum horizontal emittance of 0.76 nm was achieved. The radiation energy loss and relative energy spread were also measured using a streak-camera. The measured data show good agreement with analytical formulas and numerical simulations.

A novel algorithm for self-consistent simulations of long-range wakefield effects has been developed and applied to the study of both longitudinal and transverse coupled-bunch instabilities at NSLS-II. The algorithm is implemented in the new parallel tracking code space (self-consistent parallel algorithm for collective effects) discussed in the paper. The code is applicable for accurate beam dynamics simulations in cases where both bunch-to-bunch and intrabunch motions need to be taken into account, such as chromatic head-tail effects on the coupled-bunch instability of a beam with a nonuniform filling pattern, or multibunch and single-bunch effects of a passive higher-harmonic cavity. The numerical simulations have been compared with analytical studies. For a beam with an arbitrary filling pattern, intensity-dependent complex frequency shifts have been derived starting from a system of coupled Vlasov equations. The analytical formulas and numerical simulations confirm that the analysis is reduced to the formulation of an eigenvalue problem based on the known formulas of the complex frequency shifts for the uniform filling pattern case.

In an electron storage ring, the interaction between a single-bunch beam and a vacuum chamber impedance affects the beam parameters, which can be measured rather precisely. So we can develop beam-based numerical models of longitudinal and transverse impedances. At the Diamond Light Source (DLS) to get the model parameters, a set of measured data has been used including current-dependent shift of betatron tunes and synchronous phase, chromatic damping rates, and bunch lengthening. A matlab code for multiparticle tracking has been developed. The tracking results and analytical estimations are quite consistent with the measured data. Since Diamond has the shortest natural bunch length among all light sources in standard operation, the studies of collective effects with short bunches are relevant to many facilities including next generation of light sources.

One of the important issues of the in-vacuum undulator design is the coupling impedance of the vacuum chamber, which includes tapered transitions with variable gap size. To get complete and reliable information on the impedance, analytical estimate, numerical simulations and beam-based measurements have been performed at Diamond Light Source, a forthcoming upgrade of which includes introducing additional insertion device (ID) straights. The impedance of an already existing ID vessel geometrically similar to the new one has been measured using the orbit bump method. The measurement results in comparison with analytical estimations and numerical simulations are discussed in this paper.

Multibunch instabilities of a storage ring electron beam occur due to coherent particle oscillations generated through a bunch to bunch coupling via the impedances, deteriorating the beam quality. One cure for multibunch instabilities is Landau damping, i.e., introducing a spread in the oscillation frequencies among the particles of the individual bunches in order to destroy the coherence of the coupled multibunch oscillation. Measurements at ELETTRA have shown that the harmonic sextupole provides Landau damping capable of suppressing transverse multibunch instabilities. The damping is induced by the nonlinear tune spread with amplitude among the electrons within the individual bunches.

In the design of the vacuum chamber of a storage ring, special care has to be taken to keep the impedance as low as possible, in order to not degrade the quality of the circulating beam. Since the start of the commissioning of the Italian synchrotron light source ELETTRA in 1993, several low gap insertion vacuum chambers with internal aperture of 14 mm have been installed into the storage ring. Monitoring of their individual impedances and effects has been carried out with measurements on the electron beam after each new installation. The subsequent evolutions of the total longitudinal and transverse impedances are presented in this paper. Furthermore, in contradiction with the foreseen single-bunch effect, noticeable excitations of particular narrow band longitudinal coupled multibunch instabilities as a function of the position of the blades of the vertical scraper have been observed. In order to achieve a deeper insight of the phenomenon, an exhaustive characterization of both the longitudinal and transverse impedances of the scraper has been carried out.

Objectives: Matrix metalloproteinase 8 (MMP8) has a prominent role in collagen turnover in blood vessels and vascular remodeling. The contribution of regulatory single nucleotide polymorphisms in MMP8 to cardiovascular diseases is unclear. We aimed to delineate the influence of MMP8 promoter variations on hypertension., Methods: A case-control study in unrelated individuals ( n  = 2565) was carried out. Resequencing of the MMP8 proximal promoter, linkage disequilibrium analysis, genotyping of variants and regression analyses were performed. MMP8 promoter-reporter constructs were generated and expressed in human vascular endothelial cells under various conditions., Results: We identified four single nucleotide polymorphisms (SNPs) in the promoter region of MMP8 : -1089A/G (rs17099452), -815G/T (rs17099451), -795C/T (rs11225395), -763A/T (rs35308160); these SNPs form three major haplotypes. Hap3 (viz., GTTT haplotype) carriers showed significant associations with hypertension in two geographically distinct human populations (e.g., Chennai: odds ratio [OR] = 1.47, 95% confidence interval [CI] = 1.16-1.86, P  = 2 × 10 -3 ; Chandigarh: OR = 1.85, 95% CI = 1.21-2.81, P  = 4 × 10 -3 ). Hap3 carriers also displayed elevated systolic blood pressure, diastolic blood pressure and mean arterial pressure levels. Hap3 promoter-reporter construct showed lower promoter activity than the wild-type (Hap1) construct. In silico analysis and molecular dynamics studies predicted diminished binding of the transcription factor nuclear factor kappa B (NF-κB) to the functional -815T allele of Hap3 compared to the -815G wild-type allele; this prediction was validated by in-vitro experiments. Hap3 displayed impaired response to tumor necrosis factor-alpha treatment, possibly due to weaker binding of NF-κB. Notably, MMP8 promoter haplotypes were identified as independent predictors of plasma MMP8 and endothelial dysfunction markers (von Willebrand factor and endothelin-1) levels., Conclusion: MMP8 promoter GTTT haplotype has a functional role in reducing MMP8 expression during inflammation via diminished interaction with NF-κB and in enhancing the risk of hypertension., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)

Background: There are published reports of safety and feasibility of percutaneous coronary intervention (PCI) without contrast, using intravascular ultrasound (IVUS) and coronary physiology guidance in chronic kidney disease population. We prospectively evaluated the safety and feasibility of zero-contrast PCI technique., Methods: In this prospective study, we hypothesized that PCI is feasible without contrast, using IVUS guidance alone without mandatory coronary physiology to rule out slow-flow or no-flow at the end of PCI in a population at risk of contrast-induced acute kidney injury (CI-AKI). In this study, we included 31 vessels in 27 patients at risk of CI-AKI and assessed the primary outcome of technical success at the end of PCI. Major adverse cardio-cerebro vascular events (MACCE) and percent change in estimated glomerular filtration rate(eGFR) one month after PCI were the secondary outcomes of the study., Results: The primary outcome was met in 87.1%(n = 27) of the procedures. Technical failure was seen in 12.9%(n = 4) of the procedures. None of the patients developed MACCE at one-month follow-up. The median percent change in eGFR at one-month follow-up was -8.19%(-24.40%, +0.92%). There was no newer initiation of renal replacement therapy at one-month follow-up., Conclusions: Zero-contrast PCI is safe and feasible in selective coronary anatomies with IVUS guidance. Coronary physiology is not mandatory to rule out slow-flow or no-flow at the end of procedure. Contrast may be needed to tide over the crisis during the possible complications, namely slow-flow, geographical miss and intraprocedural thrombus., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Effective treatment for ST-elevation myocardial infarction (STEMI) includes the 24/7 availability of reperfusion therapy, which is crucial for good clinical outcomes. In low- and middle-income countries, this is hindered by disparities in resource utilisation, irregularities in access to health care and organisational gaps. Due to the inaccessibility of primary percutaneous coronary intervention (PCI) for most patients, the more feasible and practical approach of pharmacoinvasive management must be incorporated into the systems of care for STEMI. This review focuses on the development of STEMI India, a not-for-profit organisation that aims to advance the field of STEMI management by imparting and disseminating the latest information from around the world on STEMI management to all those involved in STEMI care. The STEMI India model system of care includes a 3-model framework, based on infrastructure and workforce availability, and tailored to meet the needs of the society it caters to. After the successful implementation of the "Tamil Nadu STEMI" project, a nationwide system of care for STEMI has been developed, which has been endorsed by the Cardiological Society of India (CSI) and the Association of Physicians of India (API)., Competing Interests: The authors have no conflicts of interest to declare.

Background: ST elevation myocardial infarction (STEMI) represents a large proportion of the clinical presentation of coronary artery disease in Indian people. Owing to multiple factors contributing to the sex difference, women with STEMI are thought to have a higher risk of adverse outcomes than men. The aim of this study was to evaluate sex-related differences in the clinical characteristics and prognosis of patients with STEMI within a system of care., Method: This study was a subgroup analysis of the Tamil Nadu-STEMI (TN-STEMI) program, a multicentre, prospective, observational study of a quality-improvement program studying patients with STEMI at four hub-and-spoke clusters in the southern state of Tamil Nadu, India. In total, 2,420 patients were enrolled between 2012 and 2014, and the data from all four clusters, pre- and postimplementation of integrated STEMI systems, were combined for this analysis, with a 1-year follow-up., Results: The mean ± SD age of presentation of female patients (16%) was significantly later (60.1±10.9 years) compared with males (84%; 53.7±12 years). Diabetes was more prevalent in women (35.2% vs 23.8%; p<0.001), as was hypertension (35.2% vs 22.9%; p<0.001). Symptom to first medical contact in female patients was significantly delayed compared with males (193 mins vs 170 mins; p≤0.009). Women had higher mortality, both in hospital (10.4% vs 4.8%; p≤0.001) and at 1 year (26.7% vs 13%; p≤0.001). This pattern was persistent, even in the younger STEMI (<45 years) population (in-hospital: 9.1% vs 3% [p≤0.05]; at 1 year: 18.2% vs 3% [p≤ 0.05]). In the regression model, females had a 1.8 times increased likelihood (p<0.04) of mortality after adjusting for confounders., Conclusions: Among patients with STEMI, women have an unfavourable risk profile and adverse short- and long-term prognoses when compared to men., (Copyright © 2021 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). Published by Elsevier B.V. All rights reserved.)

We presented our continuing stride to optimize the second-generation NBD entry antagonist targeted to the Phe43 cavity of HIV-1 gp120. We have synthesized thirty-eight new and novel analogs of NBD-14136, earlier designed based on a CH 2 OH "positional switch" hypothesis, and derived a comprehensive SAR. The antiviral data confirmed that the linear alcohol towards the "N" (C4) of the thiazole ring yielded more active inhibitors than those towards the "S" (C5) of the thiazole ring. The best inhibitor, NBD-14273 (compound 13), showed both improved antiviral activity and selectivity index (SI) against HIV-1 HXB2 compared to NBD-14136. We also tested NBD-14273 against a large panel of 50 HIV-1 Env-pseudotyped viruses representing clinical isolates of diverse subtypes. The overall mean data indicate that antiviral potency against these isolates improved by ~3-fold, and SI also improved ~3-fold compared to NBD-14136. This new and novel inhibitor is expected to pave the way for further optimization to a more potent and clinically relevant inhibitor against HIV-1., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Aims: Established, evidence-based measures of radiation are required to minimise its hazards, while maintaining adequate image quality. The aim of this study is to evaluate radiation data and generate reference radiation levels for commonly performed coronary catheterisation procedures in India., Methods and Results: In this prospective, observational study, all procedures were performed in accordance with the established standards using Innova IGS 520/2100-IQ catheterisation laboratories. Demographic, procedural and radiation data were collected. Dose reference limits (DRL) were established as the 75 th percentile of the total distribution. There were 2,906 coronary angiograms (CAG), 750 percutaneous coronary interventions (PCI) and 715 CAG+PCI. DRLs for dose area product were: 19.6 Gy·cm 2 for CAG, 49.8 Gy·cm 2 for PCI and 72.0 Gy·cm 2 for CAG+PCI, respectively. Median cumulative air kerma levels were: 185 mGy for CAG, 533mGy for PCI, and 891 mGy for CAG+PCI. Male gender, higher BMI, combining CAG+PCI, fluoroscopy time, number of cine frames, and image acquisition settings were significant contributors to increased radiation dose., Conclusions: This study established reference radiation dose levels for diagnostic and interventional coronary procedures in India, which were comparable to and in the lower range of international standards., Competing Interests: V. Subban has received an institutional research grant from GE Healthcare. S. Amelot is a GE Healthcare employee. The other authors have no conflicts of interest to declare.

We previously reported a milestone in the optimization of NBD-11021, an HIV-1 gp120 antagonist, by developing a new and novel analogue, NBD-14189 ( Ref1 ), which showed antiviral activity against HIV-1 HXB2 , with a half maximal inhibitory concentration of 89 nM. However, cytotoxicity remained high, and the absorption, distribution, metabolism, and excretion (ADME) data showed relatively poor aqueous solubility. To optimize these properties, we replaced the phenyl ring in the compound with a pyridine ring and synthesized a set of 48 novel compounds. One of the new analogues, NBD-14270 ( 8 ), showed a marked improvement in cytotoxicity, with 3-fold and 58-fold improvements in selectivity index value compared with that of Ref1 and NBD-11021, respectively. Furthermore, the in vitro ADME data clearly showed improvements in aqueous solubility and other properties compared with those for Ref1 . The data for 8 indicated that the pyridine scaffold is a good bioisostere for phenyl, allowing the further optimization of this molecule.

MMP (matrix metalloproteinase)-7-a potent extracellular matrix degrading enzyme-is emerging as a new regulator of cardiovascular diseases. However, potential contributions of MMP7 genetic variations to hypertension remain unknown. In this study, we probed for the association of a tag single-nucleotide polymorphism in the MMP7 promoter (-181A/G; rs11568818) with hypertension in an urban South Indian population (n=1501). The heterozygous AG genotype significantly increased risk for hypertension as compared with the wild-type AA genotype (odds ratio, 1.60 [95% CI, 1.25-2.06]; P =2.4×10 -4 ); AG genotype carriers also displayed significantly higher diastolic blood pressure and mean arterial pressure than wild-type AA individuals. The study was replicated in a North Indian population (n=949) (odds ratio, 1.52 [95% CI, 1.11-2.09]; P =0.01). Transient transfection experiments using MMP7 promoter-luciferase reporter constructs revealed that the variant -181G allele conferred greater promoter activity than the -181A allele. Computational prediction and structure-based conformational and molecular dynamics simulation studies suggested higher binding affinity for the CREB (cyclic AMP response element-binding protein) to the -181G promoter. In corroboration, overexpression/downregulation of CREB and chromatin immunoprecipitation experiments provided convincing evidence for stronger binding of CREB with the -181G promoter. The -181G promoter also displayed enhanced responses to hypoxia and epinephrine treatment. The higher promoter activity of -181G allele translated to increased MMP7 protein level, and MMP7 - 181AG heterozygous individuals displayed elevated plasma MMP7 levels, which positively correlated with blood pressure. In conclusion, the MMP7 A-181G promoter polymorphism increased MMP7 expression under pathophysiological conditions (hypoxic stress and catecholamine excess) via increased interactions with CREB and enhanced the risk for hypertension in its carriers.

Objectives: We evaluated the impact of implementation of the TN-STEMI programme on various characteristics of the pharmacoinvasive group by comparing clinical as well as angiographic outcomes between the pre- and post-implementation groups., Methods: The TN-STEMI programme involved 2420 patients of which 423 patients had undergone a pharmacoinvasive strategy of reperfusion. Of these, 407 patients had a comprehensive blinded core-lab evaluation of their angiograms post-lysis and clinical evaluation of various parameters including time-delays and adverse cardio- and cerebro-vascular events at 1year. Streptokinase was used as the thrombolytic agent in 94.6% of the patients., Results: In the post-implementation phase, there was a significant improvement in 'First medical contact (FMC)-to-ECG' (11 vs. 5min, p<0.001) and 'Lysis-to-angiogram' (98.3 vs. 18.2h, p<0.001) times. There was also a significant improvement in the number of coronary angiograms performed within 24h (20.7% vs. 69.3%, p<0.001). The 'Time-to-FMC' (160 vs. 135min, p=0.07) and 'Total ischemic time' (210 vs. 176min, p=0.22) also showed a decreasing trend. IRA patency rate (70.2% vs. 86%, p<0.001) and thrombus burden (TIMI grade 0: 49.1% vs. 73.4%, p<0.001) were superior in this group. The MACCE rates were similar except for fewer readmissions (29.8% vs. 12.6%, p=0.0002) and target revascularizations at 1year (4.8% vs. none, p=0.002) in the post-implementation group., Conclusion: The implementation of a system-of-care (hub-and-spoke model) in the pharmacoinvasive group of the TN-STEMI programme demonstrated shorter lysis-to-angiogram times, better TIMI flow patterns and lower thrombus burden in the post-implementation phase., (Copyright © 2017. Published by Elsevier B.V.)

Importance: Challenges to improving ST-segment elevation myocardial infarction (STEMI) care are formidable in low- to middle-income countries because of several system-level factors., Objective: To examine access to reperfusion and percutaneous coronary intervention (PCI) during STEMI using a hub-and-spoke model., Design, Setting, and Participants: This multicenter, prospective, observational study of a quality improvement program studied 2420 patients 20 years or older with symptoms or signs consistent with STEMI at primary care clinics, small hospitals, and PCI hospitals in the southern state of Tamil Nadu in India. Data were collected from the 4 clusters before implementation of the program (preimplementation data). We required a minimum of 12 weeks for the preimplementation data with the period extending from August 7, 2012, through January 5, 2013. The program was then implemented in a sequential manner across the 4 clusters, and data were collected in the same manner (postimplementation data) from June 12, 2013, through June 24, 2014, for a mean 32-week period., Exposures: Creation of an integrated, regional quality improvement program that linked the 35 spoke health care centers to the 4 large PCI hub hospitals and leveraged recent developments in public health insurance schemes, emergency medical services, and health information technology., Main Outcomes and Measures: Primary outcomes focused on the proportion of patients undergoing reperfusion, timely reperfusion, and postfibrinolysis angiography and PCI. Secondary outcomes were in-hospital and 1-year mortality., Results: A total of 2420 patients with STEMI (2034 men [84.0%] and 386 women [16.0%]; mean [SD] age, 54.7 [12.2] years) (898 in the preimplementation phase and 1522 in the postimplementation phase) were enrolled, with 1053 patients (43.5%) from the spoke health care centers. Missing data were common for systolic blood pressure (213 [8.8%]), heart rate (223 [9.2%]), and anterior MI location (279 [11.5%]). Overall reperfusion use and times to reperfusion were similar (795 [88.5%] vs 1372 [90.1%]; P = .21). Coronary angiography (314 [35.0%] vs 925 [60.8%]; P < .001) and PCI (265 [29.5%] vs 707 [46.5%]; P < .001) were more commonly performed during the postimplementation phase. In-hospital mortality was not different (52 [5.8%] vs 85 [5.6%]; P = .83), but 1-year mortality was lower in the postimplementation phase (134 [17.6%] vs 179 [14.2%]; P = .04), and this difference remained consistent after multivariable adjustment (adjusted odds ratio, 0.76; 95% CI, 0.58-0.98; P = .04)., Conclusions and Relevance: A hub-and-spoke model in South India improved STEMI care through greater use of PCI and may improve 1-year mortality. This model may serve as an example for developing STEMI systems of care in other low- to middle-income countries.

Aim: To assess the prevalence of suboptimal bioresorbable vascular scaffold (BVS, Abbott Vascular, Santa Clara, California) deployment in real world practice with intracoronary optical coherence tomography (OCT) imaging., Methods: Consecutive patients who underwent percutaneous coronary intervention using BVS and the final optimization assessed with OCT imaging in two tertiary care centers between December 2012 and February 2015 were evaluated for parameters of suboptimal scaffold deployment by OCT., Results: Overall, 36 scaffolds were implanted in 27 patients during this period. Mean age of the population was 54.7±8.2years and 19 (70.4%) were type B2/C lesions. The prevalence of parameters of suboptimal scaffold deployment were: underexpansion-22(61.1%), geographic miss-3(8.3%), tissue prolapse-7(25.9%), scaffold pattern irregularity-1(2.8%), longitudinal elongation-7(38.8%). Of the 7 overlaps imaged: excessive overlap was observed in 3 and scaffold gap in one. The median duration of follow up was 679days (range 193-963days). There were four events during this period. None were associated with suboptimal scaffold deployment., Conclusion: OCT based parameters of suboptimal scaffold deployment are common in real world scenario and were not associated with adverse outcomes on long term follow up. These findings need to be confirmed in larger studies., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)

Background: A pharmacoinvasive strategy may alleviate the logistical and geographical barriers in timely reperfusion of ST-segment elevation myocardial infarction (STEMI), especially in a developing country like India., Aim: To assess the safety and efficacy of pharmacoinvasive strategy versus primary PCI in STEMI patients at 2 years., Methods: Patients enrolled in STEPP-AMI, an observational, multicenter, prospective study of 200 patients presenting with STEMI, were followed up for 2 years. Group 'A' comprised of patients with pharmacoinvasive strategy (n=45), and patients who underwent primary PCI (n=155) formed group 'B'. Primary endpoint was composite of death, cardiogenic shock, reinfarction, repeat revascularization of the culprit artery, or congestive heart failure at 30 days, with follow-up till 2 years., Results: The primary endpoint occurred in 11.1% and 17.8% in group A and in 3.9% and 13.6% in group B, at 30 days and 2 years, respectively (p=0.07, RR=2.87; 95% CI: 0.92-8.97 at 30 days and p=0.47, RR=1.31; 95% CI: 0.62-2.76). There was no difference in bleeding risk between groups, 2.2% in group A and 0.6% in group B ('p'=0.4). The infarct-related artery patency varied at angiogram; it was 82.2% in arm A and 22.6% in arm B ('p'<0.001). In group A, failed fibrinolysis occurred in 12.1%., Conclusion: A pharmacoinvasive strategy resulted in outcomes that were comparable with primary PCI at 2 years, suggesting it might be a viable option in India. Larger studies are required to confirm these findings., (Copyright © 2015 Cardiological Society of India. Published by Elsevier B.V. All rights reserved.)

The health care burden of ST elevation myocardial infarction (STEMI) in India is enormous. Yet, many patients with STEMI can seldom avail timely and evidence based reperfusion treatments. This gap in care is a result of financial barriers, limited healthcare infrastructure, poor knowledge and accessibility of acute medical services for a majority of the population. Addressing some of these issues, STEMI India, a not-for-profit organization, Cardiological Society of India (CSI) and Association Physicians of India (API) have developed a protocol of "systems of care" for efficient management of STEMI, with integrated networks of facilities. Leveraging newly-developed ambulance and emergency medical services, incorporating recent state insurance schemes for vulnerable populations to broaden access, and combining innovative, "state-of-the-art" information technology platforms with existing hospital infrastructure, are the crucial aspects of this system. A pilot program was successfully employed in the state of Tamilnadu. The purpose of this article is to describe the framework and methods associated with this programme with an aim to improve delivery of reperfusion therapy for STEMI in India. This programme can serve as model STEMI systems of care for other low-and-middle income countries., (Copyright © 2015 Cardiological Society of India. Published by Elsevier B.V. All rights reserved.)

Background: Contrast induced nephropathy (CIN) is associated with significant morbidity and mortality after percutaneous coronary intervention (PCI). The aim of this study is to evaluate the collective probability of CIN in Indian population by developing a scoring system of several identified risk factors in patients undergoing PCI., Methods: This is a prospective single center study of 1200 consecutive patients who underwent PCI from 2008 to 2011. Patients were randomized in 3:1 ratio into development (n = 900) and validation (n = 300) groups. CIN was defined as an increase of ≥25% and/or ≥0.5 mg/dl in serum creatinine at 48 hours after PCI when compared to baseline value. Seven independent predictors of CIN were identified using logistic regression analysis - amount of contrast, diabetes with microangiopathy, hypotension, peripheral vascular disease, albuminuria, glomerular filtration rate (GFR) and anemia. A formula was then developed to identify the probability of CIN using the logistic regression equation., Results: The mean (±SD) age was 57.3 (±10.2) years. 83.6% were males. The total incidence of CIN was 9.7% in the development group. The total risk of renal replacement therapy in the study group is 1.1%. Mortality is 0.5%. The risk scoring model correlated well in the validation group (incidence of CIN was 8.7%, sensitivity 92.3%, specificity 82.1%, c statistic 0.95)., Conclusion: A simple risk scoring equation can be employed to predict the probability of CIN following PCI, applying it to each individual. More vigilant preventive measures can be applied to the high risk candidates., (Copyright © 2014 Cardiological Society of India. Published by Elsevier B.V. All rights reserved.)

Objective: To compare the efficacy of pharmacoinvasive strategy versus primary percutaneous coronary intervention (PCI) in patients with ST-segment elevation myocardial infarction (STEMI). Primary PCI is the preferred treatment for STEMI, but it is not a feasible option for many. A pharmacoinvasive strategy might be a practical solution in the Indian context, although few empirical data exist to guide this approach., Methods: This is a prospective, observational, multicentre pilot study. Two hundred consecutive patients with STEMI aged 18-75 years, presenting within 12 h of onset of symptoms and requiring a reperfusion strategy, were studied from five primary PCI capable centres in South India. Patients who opted for pharmacoinvasive strategy (n=45) formed group A. Group B consisted of patients treated with primary PCI (n=155). One patient was lost to follow-up at 1 year. The primary end point was a composite of death, cardiogenic shock, reinfarction, repeat revascularisation of a culprit artery and congestive heart failure at 30 days., Results: The primary end point occurred in 11.1% in group A and in 3.9% in group B, p=0.07 (RR=2.87; 95% CI 0.92 to 8.97). The infarct-related artery patency at angiogram was 82.2% in group A and 22.6% in group B (p<0.001). PCI was performed in 73.3% in group A versus 100% in group B (p<0.001), and a thrombus was present in 26.7% in group A versus 63.2% in group B (p<0.001). Failed fibrinolysis occurred in 12.1% in group A. There was no difference in bleeding risk, 2.2% in group A versus 0.6% in group B, (p=0.4)., Conclusions: This pilot study shows that a pharmacoinvasive strategy can be implemented in patients not selected for primary PCI in India and hints at the possibility of similar outcomes. Larger studies are required to confirm these findings., Trial Registration Number: TRIAL IS REGISTERED WITH CLINICAL TRIAL REGISTRY OF INDIA, CTRI NUMBER: REF/2011/07/002556.

Objective: To assess the feasibility and outcomes of primary percutaneous coronary intervention (PPCI) for ST-segment elevation myocardial infarction (STEMI) in Indian Scenario., Methods: Between January 2005 and December 2012, consecutive STEMI patients who underwent PPCI within 12 h of onset of chest pain were prospectively enrolled in a PPCI registry. Patient demographics, risk factors, procedural characteristics, time variables and in-hospital and 30 day major adverse cardiovascular events (MACE) [death, reinfarction, bleeding, urgent coronary artery bypass surgery (CABG) and stroke] were assessed., Results: A total of 672 patients underwent PPCI during this period. The mean age was 52 ± 13.4 years and 583 (86.7%) were males, 275 (40.9%) were hypertensives and 336 (50%) were diabetics. Thirty one (4.6%) patients had cardiogenic shock (CS). Anterior myocardial infarction was diagnosed in 398 (59.2%) patients. The median chest pain onset to hospital arrival time, door-to-balloon time and total ischemic times were 200 (10-720), 65 (20-300), and 275 (55-785) minutes respectively. In-hospital adverse events occurred in 54 (8.0%) patients [death 28 (4.2%), reinfarction 8 (1.2%), major bleeding 9 (1.3%), urgent CABG 4 (0.6%) and stroke 1 (0.14%)]. Nineteen patients with CS died (mortality rate - (61.3%)). At the end of 30 days, 64 (9.5%) patients had MACE [death 35 (5.2%), reinfarction 10 (2.1%), major bleeding 10 (1.5%), urgent CABG 4 (0.6%) and stroke 1 (0.1%)]., Conclusion: Our study has shown that PPCI is feasible with good outcomes in Indian scenario. Even though the recommended door-to-balloon time can be achieved, the total ischemic time remained long. CS in the setting of STEMI was associated with poor outcomes., (Copyright © 2013 Cardiological Society of India. Published by Elsevier B.V. All rights reserved.)

Introduction: Over the past two decades, India has witnessed a staggering increase in the incidence and mortality of ST-elevation myocardial infarction (STEMI). Indians have higher rates of STEMI and younger populations that suffer from it when compared with developed countries. Yet, the recommended reperfusion therapy with fibrinolysis and percutaneous coronary intervention is available only to a minority of patients. This gap in care is a result of financial barriers, limited healthcare infrastructure and poor knowledge and accessibility of acute medical services for a majority of its population., Methods and Analysis: This is a prospective, multicentre, 'pretest/post-test' quasi-experimental, community-based study. This programme will use a 'hub-and-spoke' model of an integrated healthcare network based on clusters of primary-care health clinics, small hospitals and large tertiary-care facilities. It is an 'all-comers' study which will enrol consecutive patients presenting with STEMI to the participating hospitals. The primary objectives of the study is to improve the use of reperfusion therapy and reduce the time from first medical contact to device or drug in STEMI patients; and to increase the rates of early invasive risk stratification with coronary angiography within 3-24 h of fibrinolytic therapy in eligible patients through changes in process of care. Outcomes will be measured with statistical comparison made before and after implementing the TN-STEMI programme. The estimated sample size is based on the Kovai Erode Pilot study, which provided an initial work on establishing this type of programme in South India. It will be adequately powered at 80% with a superiority margin of 10% if 36 patients are enrolled per cluster or 108 patients in three clusters. Thus, the enrolment period of 9 months will result in a sample size of 1500 patients., Ethics: This study will be conducted in accordance with the ethical principles that have their origin in the current Declaration of Helsinki and 'ethical guidelines for biomedical research on human participants' as laid down by the Indian Council for Medical Research. All participating hospitals will still obtain local ethics committee approval of the study protocol and written informed consent will be obtained from all participants., Dissemination and Results: Our findings will be reported through scientific publications, research conferences and public policy venues aimed at state and local governments in India. If successful, this model can be extended to other areas of India as well as serve as a model of STEMI systems of care for low-income and middle-income countries across the world., Registration: Trial is registered with Clinical trial registry of India, No: CTRI/2012/09/003002.

Background/aims: To assess the factors causing delay in attaining DTB time of <90 min., Methods: Eighty-five patients who underwent primary PCI from August 2008 to July 2009 were studied. From door-to-balloon, time was divided into 6 stages; any reason for delay was studied., Results: The mean DTB time was 80.5 min (SD = 34.4, median time 75 min, range 30-195). DTB time was <90 min in 76.5%, and DTB time >90 min occurred in 23.5%. Mean door to ECG - 6.5 min (SD = 2.7), mean time for the decision of PCI - 7.5 min (SD = 10.5), mean time taken for the patient's consent - 19.6 min (SD = 17.6), for STEMI team activation - 6.7 min (SD = 7.6), average time for financial process - 39.2 min (SD = 22.9). Average time for sheath to balloon - 5.2 min (SD = 1.7). Hospital related delay occurred in 5%, patient related delay in 80%, both together in 15%. 89.5% of patient related delay was due to delay in giving consent and financial reasons. There was no statistically significant delay for patients presented at morning or night and during the weekdays or weekend. Total mortality was 4.7%. Mortality among <90 min was 3.1%, mortality among >90 min was 10% ('p' = 0.2)., Conclusions: With effective hospital strategies, the DTB time of 90 min can be achieved in majority of patients. The chief delay in DTB time in this study was due to a delay in obtaining consent and financial reasons., (Copyright © 2012 Cardiological Society of India. Published by Elsevier B.V. All rights reserved.)

Apical ballooning syndrome (Takotsubo cardiomyopathy) is an unusual stress-related reversible cardiomyopathy occurring commonly in postmenopausal females. Genetic etiology of this condition is uncertain. A 68-year-old female and her daughter aged 43 got admitted to our institute simultaneously with acute chest pain following demise of one of their close relative. Both had features typical of Takotsubo cardiomyopathy and recovered completely. This reports point to the possible genetic predisposition to this abnormality., (Copyright © 2012 Cardiological Society of India. Published by Elsevier B.V. All rights reserved.)

A single coronary artery is a rare coronary anomaly. A 68-year-old male underwent coronary angiography for recent inferior wall myocardial infarction. It revealed a common coronary trunk arising from the right sinus of Valsalva and bifurcated into the right coronary artery (RCA) and anterior descending coronary arteries. The RCA, after its usual distribution in the right atrioventricular groove, continued as the left circumflex artery in the left atrioventricular groove. There were significant stenoses in the mid and distal RCA, which were treated percutaneously.

Coronary stents, especially drug eluting stents (DES), have revolutionized the practice of interventional cardiology. Newer stents are manufactured by altering basic design characteristics to tackle complex coronary morphologies more effectively. Alteration in one particular attribute might affect other attributes adversely. Even though, reduction in the number and alteration of the orientation of the connectors improves the stent flexibility and deliverability, it adversely decreases the axial strength of the stent with resulting longitudinal stent deformation. A 67 year old female underwent percutaneous coronary intervention for a mid left anterior descending artery stenosis with a 2.75 × 16 mm Promus Element stent (Boston Scientific, Natick, Massachusetts). The stent got longitudinally distorted during post-stent balloon dilatation which was effectively managed with further dilatation with non-compliant balloon., (Copyright © 2012 Cardiological Society of India. Published by Elsevier B.V. All rights reserved.)