Abstract We present the second NuSTAR and XMM-Newton extragalactic survey of the JWST north ecliptic pole (NEP) time-domain field (TDF). The first NuSTAR NEP-TDF survey had 681 ks total exposure time ...executed in NuSTAR cycle 5 in 2019 and 2020. This second survey, acquired from 2020 to 2022 in cycle 6, adds 880 ks of NuSTAR exposure time. The overall NuSTAR NEP-TDF survey is the most sensitive NuSTAR extragalactic survey to date, and a total of 60 sources were detected above the 95% reliability threshold. We constrain the hard X-ray number counts, log N – log S , down to 1.7 × 10 −14 erg cm −2 s −1 at 8–24 keV and detect an excess of hard X-ray sources at the faint end. About 47% of the NuSTAR-detected sources are heavily obscured ( N H > 10 23 cm −2 ), and 18 − 8 + 20 % of the NuSTAR-detected sources are Compton-thick ( N H > 10 24 cm −2 ). These fractions are consistent with those measured in other NuSTAR surveys. Four sources presented >2 σ variability in the 3 yr survey. In addition to NuSTAR, a total of 62 ks of XMM-Newton observations were taken during NuSTAR cycle 6. The XMM-Newton observations provide soft X-ray (0.5–10 keV) coverage in the same field and enable more robust identification of the visible and infrared counterparts of the NuSTAR-detected sources. A total of 286 soft X-ray sources were detected, out of which 214 XMM-Newton sources have secure counterparts from multiwavelength catalogs.
Phenethyltriflamides react with 1,3-dienes upon treatment with a catalytic amount of Pd(OAc)2 and Cu(OAc)2/O2 as oxidant to afford chemo-, regio- and diastereoselectively ...2,3,4,5-tetrahydro-1H-benzodazepines (3-benzazepine derivatives) in good to excellent yields. A DFT study of the 5 + 2 heteroannulation suggests a mechanistic pathway starting with formation of the six-membered palladacycle cis-PdX2L2 via a CMD process followed by η2 coordination and insertion of the 1,3-diene unit in a diastereoselective manner.
Ruthenium vinyl carbenes derived from Cp/Cp*RuCl‐based complexes (Cp=cyclopentadiene, Cp*=1,2,3,4,5‐pentamethylcyclopentadiene) have been routinely invoked as key intermediates in tandem reactions ...involving a carbene/alkyne metathesis (CAM). A priori, these intermediates resemble the Grubbs‐type family of catalysts, but they exhibit a completely different reactivity pattern that few, if any, other catalytic system can reproduce so far. The reactivity of these species with α‐unsubstituted and α‐substituted alkynals showcases the peculiarities of these intermediates. Although Z‐vinyl dihydrooxazines are preferentially obtained with the former, Z‐vinyl epoxypyrrolidines are obtained with the latter. A combination of spectroscopic and computational data now prove that a η3‐coordination mode of the ruthenium vinyl carbene and the presence of a Lewis basic chloride ligand give rise to two markedly different stereoelectronic faces, which are responsible for the unconventional reactivity of these species.
Two‐faced complex: Ruthenium vinyl carbenes derived from Cp/Cp*RuCl‐based complexes (Cp=cyclopentadiene, Cp*=1,2,3,4,5‐pentamethylcyclopentadiene) exhibit a completely different reactivity pattern that few, if any, other catalytic system can reproduce so far. A combination of spectroscopic and computational data prove that the η3‐coordination mode of ruthenium vinyl carbene and the presence of a Lewis basic chloride ligand give rise to two markedly different stereoelectronic faces, which are responsible for the unconventional reactivity of these species.
Current Internet of Things (IoT) scenarios have to deal with many challenges especially when a large amount of heterogeneous data sources are integrated, that is, data curation. In this respect, the ...use of poor‐quality data (i.e., data with problems) can produce terrible consequence from incorrect decision‐making to damaging the performance in the operations. Therefore, using data with an acceptable level of usability has become essential to achieve success. In this article, we propose an IoT‐big data pipeline architecture that enables data acquisition and data curation in any IoT context. We have customized the pipeline by including the DMN4DQ approach to enable us the measuring and evaluating data quality in the data produced by IoT sensors. Further, we have chosen a real dataset from sensors in an agricultural IoT context and we have defined a decision model to enable us the automatic measuring and assessing of the data quality with regard to the usability of the data in the context.
The Cp*RuCl-based catalyst enables expedient access to a variety of benzofused six-membered azaheterocycles from unprotected o-alkynylanilines and trimethylsilyldiazomethane through an unprecedent ...tandem carbene/alkyne metathesis/N–H insertion reaction. The transformation takes place under mild reaction conditions (room temperature, <15 min) and with excellent functional group tolerance. The synthetic utility of the final products and a mechanistic rationale are also discussed.
El acoso escolar conforma una de las experiencias victimizantes más comunes en la infancia y la adolescencia. La literatura científica ha evidenciado que la exposición a contenidos violentos se ...asocia a una mayor predisposición a la hora de perpetrar y/o ser víctima de acoso o de ciberacoso. En este sentido, diferentes estudios han destacado la importancia que el consumo de determinado tipo de videojuegos puede tener a este nivel. El presente trabajo tuvo como objetivo analizar la relación entre el consumo de videojuegos PEGI18 con contenidos de violencia explícita y las tasas de bullying y cyberbullying. Se llevó a cabo un estudio de carácter exploratorio, accediendo a una muestra total de 2,083 estudiantes de primaria y secundaria con edades comprendidas entre los 10 y los 17 años. Se empleó un cuestionario autoadministrado que incluía el European Bullying Intervention Project Questionnaire y el European Cyberbullying Intervention Project Questionnaire, junto a ítems relativos al consumo de videojuegos. Los resultados permiten constatar la existencia de una relación estadísticamente significativa entre el consumo de videojuegos violentos, el bullying y el cyberbullying, especialmente a edades tempranas. Los hallazgos remarcan la necesidad de una regulación más eficaz, que asegure un ajuste entre los videojuegos consumidos y la edad del usuario.
Varela and Saa survey transition-metal-mediated synthesis of pyridines and pyridones by (12 + 2 + 2) cycloaddition of alkynes to nitriles or isocyanates, respectively, concentrating in particular on ...the advances that have been made in the 1994-2002 period.
Mechanistic pathways for the cyclization of 1,5-alkynylacetal with N2CHTMS in the presence of Cp- and Cp*RuCl(cod) to afford (Z)- and (E)-(trimethylsilyl)vinyl spiroacetals have been calculated. ...Calculations show the presence of three conformers in equilibrium for the initially formed ruthenium carbenes. Differences in the stabilities and reactivities of the conformers, depending on the use of a Cp or Cp* ruthenium catalyst, are responsible for the favorable active reaction pathways in each case, even though the geometry of the resulting product is the same regardless of the catalyst used. Kinetic Monte Carlo (KMC) simulations with rate coefficients, including tunneling probabilities for the hydride transfer step, were used to model the evolution of reactants, intermediates, and products for all calculated pathways. It was shown that one path is almost exclusively active for each catalyst. Finally, the energetic span model of Kozuch and Shaik was used to calculate the energetic span (δE), the TOF-determining transition state (TDTS), the TOF-determining intermediate (TDI), and the TOF value for each of the feasible mechanistic pathways.
Functionalized bicyclic 1,3-cyclohexadienes can be easily prepared by a new cascade reaction which involves the Ru-catalyzed addition of acyclic alkenes to 1,6-diynes to give (Z)-hexatrienes, ...followed by a pure thermal 6e-π electrocyclization.
The use of mobile devices has undergone rapid growth in recent years. However, on some occasions, security has been neglected when developing applications. SSL/TLS has been used for years to secure ...communications although it is not a vulnerability-free protocol. One of the most common vulnerabilities is SSL pinning bypassing. This paper first describes some security controls to help protect against SSL pinning bypassing. Subsequently, some existing methods for bypassing are presented and two new methods are defined. We performed some experiments to check the use of security controls in widely used applications, and applied SSL pinning bypassing methods. Finally, we created an applicability framework, relating the implemented security controls and the methods that are applicable. This framework provides a guideline for pentesters and app developers.
![Palladium-Catalyzed [5 + 2]...](http://api.summon.serialssolutions.com/2.0.0/image/issn/XR4PS5YY4K/1523-7060_1523-7052/small "Palladium-Catalyzed [5 + 2] Heteroannulation of Phenethylamides with 1,3-Dienes to Dopaminergic 3‑Benzazepines")
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