Increased Risk in Patients With High Platelet Aggregation Receiving Chronic Clopidogrel Therapy Undergoing Percutaneous Coronary Intervention Is the Current Antiplatelet Therapy Adequate?

ObjectivesWe sought to determine whether patients receiving chronic clopidogrel therapy undergoing nonemergent stenting who display high on-treatment preprocedural platelet aggregation measured by standard light transmittance aggregometry and thrombelastography (TEG) will be at increased risk for poststenting ischemic events.BackgroundPatients exhibiting heightened platelet reactivity to adenosine diphosphate (ADP) might be at increased risk for recurrent ischemic events after coronary stenting.MethodsA total of 100 consecutive patients receiving chronic antiplatelet therapy consisting of aspirin (325 mg qd) and clopidogrel (75 mg qd) were studied before undergoing nonemergent stenting. Patients were followed for 1 year after coronary stenting for the occurrence of death, myocardial infarction, stent thrombosis, stroke, or ischemia requiring a hospital stay.ResultsAll patients were aspirin responsive. Patients with ischemic events (23 of 100, 23%) within 1 year had greater on-treatment prestent ADP-induced platelet aggregation than patients without ischemic events by aggregometry and TEG (p < 0.001 for both measurements). Of patients with an ischemic event, 70% and 87% displayed high on-treatment platelet reactivity at baseline by aggregometry and TEG, respectively. High on-treatment platelet reactivity as measured by aggregometry and TEG were the only variables significantly related to ischemic events (p < 0.001 for both assays). The administration of eptifibatide reduced periprocedural elevation in platelet reactivity, with no significant differences in bleeding events.ConclusionsPatients receiving chronic clopidogrel therapy undergoing nonemergent percutaneous coronary intervention who exhibit high on-treatment ADP-induced platelet aggregation are at increased risk for postprocedural ischemic events. These findings might have implications for the alteration in clopidogrel maintenance dose and use of glycoprotein IIb/IIIa inhibitors in selected patients

A Sensitive Search for Supernova Emission Associated with the Extremely Energetic and Nearby GRB 221009A

We report observations of the optical counterpart of the long gamma-ray burst (LGRB) GRB 221009A. Due to the extreme rarity of being both nearby ($z = 0.151$) and highly energetic ($E_{\gamma,\mathrm{iso}} \geq 10^{54}$ erg), GRB 221009A offers a unique opportunity to probe the connection between massive star core collapse and relativistic jet formation across a very broad range of $\gamma$-ray properties. Adopting a phenomenological power-law model for the afterglow and host galaxy estimates from high-resolution Hubble Space Telescope imaging, we use Bayesian model comparison techniques to determine the likelihood of an associated SN contributing excess flux to the optical light curve. Though not conclusive, we find moderate evidence ($K_{\rm{Bayes}}=10^{1.2}$) for the presence of an additional component arising from an associated supernova, SN 2022xiw, and find that it must be substantially fainter ($<$ 67% as bright at the 99% confidence interval) than SN 1998bw. Given the large and uncertain line-of-sight extinction, we attempt to constrain the supernova parameters ($M_{\mathrm{Ni}}$, $M_{\mathrm{ej}}$, and $E_{\mathrm{KE}}$) under several different assumptions with respect to the host galaxy's extinction. We find properties that are broadly consistent with previous GRB-associated SNe: $M_{\rm{Ni}}=0.05$ - $0.25 \, \rm{M_\odot}$, $M_{\rm{ej}}=3.5$ - $11.1 \, \rm{M_\odot}$, and $E_{\rm{KE}} = (1.6$ - $5.2) \times 10^{52} \, \rm{erg}$. We note that these properties are weakly constrained due to the faintness of the supernova with respect to the afterglow and host emission, but we do find a robust upper limit on the $M_{\rm{Ni}}$ of $M_{\rm{Ni}}<0.36\, \rm{M_\odot}$. Given the tremendous range in isotropic gamma-ray energy release exhibited by GRBs (7 orders of magnitude), the SN emission appears to be decoupled from the central engine in these systems.Comment: 18 pages, accepted to ApJL, 4 tables, 5 figures. Updated abstract in Previe

Designer carbon nanotubes for contaminant removal in water and wastewater: A critical review

The search for effective materials for environmental cleanup is a scientific and technological issue of paramount importance. Among various materials, carbon nanotubes (CNTs) possess unique physicochemical, electrical, and mechanical properties that make them suitable for potential applications as environmental adsorbents, sensors, membranes, and catalysts. Depending on the intended application and the chemical nature of the target contaminants, CNTs can be designed through specific functionalization or modification processes. Designer CNTs can remarkably enhance contaminant removal efficiency and facilitate nanomaterial recovery and regeneration. An increasing number of CNT-based materials have been used to treat diverse organic, inorganic, and biological contaminants. These success stories demonstrate their strong potential in practical applications, including wastewater purification and desalination. However, CNT-based technologies have not been broadly accepted for commercial use due to their prohibitive cost and the complex interactions of CNTs with other abiotic and biotic environmental components. This paper presents a critical review of the existing literature on the interaction of various contaminants with CNTs in water and soil environments. The preparation methods of various designer CNTs (surface functionalized and/or modified) and the functional relationships between their physicochemical characteristics and environmental uses are discussed. This review will also help to identify the research gaps that must be addressed for enhancing the commercial acceptance of CNTs in the environmental remediation industry

Evaluation of a Microwave Receiver Based on a Track and Hold Amplifier

Our project objective was to evaluate a new circuit topology to explore if it could be integrated into an existing superheterodyne receiver chain, making a smaller and simpler RF front-end. A traditional superheterodyne receiver was built and measured so we could easily compare and contrast characteristics between the two models. Using the same parameters, we evaluated the new wide-band track-and-hold amplifier and compared the two models. Our testing and research has shown that while the device does work, the following significant problems must be overcome for the track-and-hold amplifier to be implemented in the superheterodyne chain: rotating IF frequency, poor linearity, instability at integer multiples of the clock, and precise phase locking

Conversion of the defense industry in Russia and Eastern Europe: proceedings of the BICC/CISAC workshop on conversion, 10 - 13 August 1994

SIGLEAvailable from Bibliothek des Instituts fuer Weltwirtschaft, ZBW, Duesternbrook Weg 120, D-24105 Kiel C 201862 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman

Forex Trading and Investment

Trillions of dollars every day go through financial district of New York. Many of the wealthiest people in the United States and the world attribute their fortune being made in the financial markets. After realizing that there is plenty of money to be made, it poses the question how does one learn to trade? While people can be taught terms, indicators, and general knowledge, there is a type of mentality and talent that one needs to have to be a good trader. If one can create a great program or have a great strategy to make money in the financial district, then starting a company and managing money for other people is not far off in their future. The focus of our IQP is learning how to trade in the forex market and seeing how realistic it is to start a company off of what we learned

Mental Health Service Use amongst Veterans in a Peer-Mentor Intervention: An Analysis of Barriers to Treatment

Many returning Operation Enduring Freedom/Operation Iraqi Freedom veterans may benefit from psychological services as recent estimates suggest high rates of suicide, trauma, and psychopathology within this population. However, only a small portion of veterans ever seek mental health services, presumably due to various barriers to treatment. A better understanding of barriers to treatment may ensure that these populations seek the services they require. Data from a randomized controlled trial (RCT) of a peer-mentor program was examined to assess the extent to which common barriers to treatment precluded veterans from requesting medical or mental health assistance. The relationship between elevated scores on posttraumatic stress disorder (PTSD) and alcohol misuse measures was examined as they relate to veterans’ choices to seek assistance with health care, along with score profiles on a variety of measures (including quality of life, somatization, combat exposure, and demographic variables). Results indicated that having PTSD was a significant predictor of health service seeking, although this relationship was no longer significant once quality of life was added into analyses. Alcohol misuse and combat exposure were not significantly predictive of seeking health services, while elevated somatic symptoms were. Cumulative disadvantage theory is used to explore these findings and treatment implications