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Comprehensive Summary An efficient transannular cyano migration is reported for gem‐dicyano‐1,6‐diene, which is triggered by the addition of external arylsulfonyl radicals. The overall transformation proceeds through a sequence of intramolecular 5‐exo‐trig cyclization, suprafacial 1,4‐cyano migration, and the capture by H or D atom, leading to the production of valuable polysubstituted cyclopentanes under mild photoredox catalytic conditions. The reaction is adapted to a wide range of sodium (hetero)arylsulfinates, demonstrating good functional group compatibility. This method provides a new protocol for radical‐mediated functional group migration. [ABSTRACT FROM AUTHOR]

The functionalization of pyridines is crucial for the rapid construction and derivatization of agrochemicals, pharmaceuticals, and materials. Conventional functionalization approaches have primarily focused on the ortho‐ and para‐positions, while achieving precise meta‐selective functionalization, particularly at the C5 position in substituted pyridines, remains a formidable challenge due to the intrinsic electronic properties of pyridines. Herein, we present a new strategy for meta‐ and C5‐selective C−H sulfonylation of N‐amidopyridinium salts, which employs a transient enamine‐type intermediate generated through a nucleophilic addition to N‐amidopyridinium salts. This process harnesses the power of electron donor‐acceptor complexes, enabling high selectivity and broad applicability, including the construction of complex pyridines bearing valuable sulfonyl functionalities under mild conditions without the need for an external photocatalyst. The remarkable C5 selectivity, combined with the broad applicability to late‐stage functionalization, significantly expands the toolbox for pyridine functionalization, unlocking access to previously unattainable meta‐sulfonylated pyridines. [ABSTRACT FROM AUTHOR]

Carbyne free radicals (RC) are usually associated with high‐energy processes, thus research on their preparation, chemical reactivity, and prevalence under mild conditions is scarce. Recently, it was reported that metallo‐complexes containing CR ligands may undergo spontaneous degradation in aqueous solutions to produce free RC radicals. These highly reactive species may react with each other to form the corresponding alkyne and other products. The reaction of 1,1,1 halo‐carbo‐hydrates with Cr(II) ions also forms RC radicals under mild conditions. Herein, we report two additional synthetic routes that produce free RC radicals under mild conditions. First, the reaction between metallic zinc and acetic anhydride produces 2‐butyne and several other C2, C3, and C4 compounds. Isotopic‐labeling experiments indicate that the formation of 2‐butyne results from an inter‐molecular reaction in which two RC moieties from two acetic anhydride molecules combine in solution. In addition, the degradation of the tri‐molybdenum complex [Mo3(H3CC≡CCH3)(OAc)(H2O)2Br7], in which a 2‐butyne ligand is coordinated to the Mo3 framework in a μ3‐η2 (⊥) binding mode in aqueous solution produces several C2, C3, C4 and C5 molecules. This indicates the formation of free CH3C radicals by a homolytic cleavage of the carbon‐carbon triple bond. [ABSTRACT FROM AUTHOR]

Transition metal‐catalyzed cross‐coupling reactions have become a powerful and widely used synthetic approach for the construction of both carbon‐carbon and carbon‐heteroatom bonds. These reactions have revolutionized synthetic chemistry by enabling the efficient formation of complex molecular architectures. Among the various methods available, the bimolecular homolytic substitution (SH2) reaction has emerged as an attractive and versatile method for the formation of C(sp3)−C(sp3) and C(sp3)‐heteroatom bonds. In recent years, significant progress has been made in the development of radical SH2 reactions, particularly those involving different transition metal complexes such as cobalt, nickel, and iron. These advancements have expanded the scope of SH2 reactions, allowing for greater diversity in substrate compatibility and reaction conditions. In this review, we aim to highlight the latest breakthroughs and mechanistic insights into radical SH2 reactions, focusing on the role of transition metal catalysts in facilitating these transformations. We will discuss the various types of transition metal complexes that have been employed, the mechanistic pathways involved, and the potential applications of these reactions in the synthesis of complex organic molecules. [ABSTRACT FROM AUTHOR]

In the context of traditionalist tendencies in the Russian religious space in 2000–2010, Salafism became the object of intense discursive production. Interpretations range from explicit criticism to the identification of its modernizing potential. The article analyzes various approaches at both federal and local levels, using the regions of Dagestan and Tatarstan as examples. Despite the politically polarized character of the discussion, these actors share important fundamental assumptions. These trends are compared with the French debate by Olivier Roy and Gilles Kepel and are analyzed in relation to secularization theories. [ABSTRACT FROM AUTHOR]

Electrochromic systems capable of switching absorption in the near‐infrared (NIR) region (750–2500 nm) are attractive from the viewpoint of applications for material and life science, and thus several examples have been reported to date. In general, the development of organic‐based systems is needed to reduce the environmental impact and improve biocompatibility. Although extending the switchable spectral range is crucial for the application of organic electrochromic molecules, the switching of NIR absorption based on redox interconversion is still a challenging issue regarding reversibility and durability during interconversion. To overcome this potential instability, the introduction of heteroatoms into the molecular backbone and/or π‐extension could be useful strategies in terms of effective delocalization of charge and spin in the corresponding redox states. In this review, we focus on redox‐active well‐defined small molecules that enable ON/OFF switching of NIR absorption based on precise control of the redox states, and present recent studies on their intrinsic electrochemical and spectroscopic properties and/or structural characterization of their charged states. [ABSTRACT FROM AUTHOR]

Open‐shell organic radical semiconductor materials have received increasing attention in recent years due to their distinctive properties compared to the traditional materials with closed‐shell singlet ground state. However, their poor chemical and photothermal stability in ambient conditions remains a significant challenge, primarily owing to their high reactivity with oxygen. Herein, a novel open‐shell poly(3,4‐dioxythiophene) radical PTTO2 is designed and readily synthesized for the first time using low‐cost raw material via a straightforward BBr3‐demethylation of the copolymer PTTOMe2 precursor. The open‐shell character of PTTO2 is carefully studied and confirmed via the signal‐silent 1H nuclear magnetic resonance spectrum, highly enhanced electron spin resonance signal compared with PTTOMe2, as well as the ultra‐wide ultraviolet‐visible‐near nfraredUV–vis–NIR absorption and other technologies. Interestingly, the powder of PTTO2 exhibits an extraordinary absorption range spanning from 300 to 2500 nm and can reach 274 °C under the irradiation of 1.2 W cm−2, substantially higher than the 108 °C achieved by PTTOMe2. The low‐cost PTTO2 stands as one of the best photothermal conversion materials among the pure organic photothermal materials and provides a new scaffold for the design of stable non‐doped open‐shell polymers. [ABSTRACT FROM AUTHOR]

A visible-light-initiated electron-donor–acceptor (EDA) complex-driven regioselective vicinal and oxidative geminal thiosulfonylation of alkynes is presented. Organic thiosulfonates act as an acceptor, producing either sulfonyl (RSO2˙) or thiyl (RS˙) radicals under base and solvent switchable conditions. Simultaneous installation of three different functionalities, viz carbonyl, sulfonyl, and thiyl, takes place under one condition, while another condition leads to vicinal thiolation and sulfonylation. [ABSTRACT FROM AUTHOR]

Radiolytically generated radicals cause degradation of nutrients in food, materials in satellites and solar cells, and human health. Radiation effects are studied using gamma radiolysis, a low-throughput, high-cost, and low-accessibility method. We developed a higher-throughput, low-cost, non-radioactive, radical assay that produces radicals similar to those generated in gamma radiolysis and examined monoamide degradation. Our radical assay results correspond to those from gamma irradiation in both monoamide stability and decomposition products, establishing this radical assay as a proof-of-concept screening tool for radiolytic stability. [ABSTRACT FROM AUTHOR]

In recent times, diaryliodonium reagents (DAIRs) have witnessed a resurgence as arylating reagents, especially under photoinduced conditions. However, reactions proceeding through electron donor‐acceptor (EDA) complex formation with DAIRs are restricted to electron‐rich reacting partners serving as donors due to the well‐known cage effect. We discovered a practical and high‐yielding visible‐light‐induced EDA platform to generate aryl radicals from the corresponding DAIRs and use them to synthesize key chalcogenides. In this process, an array of DAIRs and dichalcogenides react in the presence of 1,4 diazabicyclo[2.2.2]octane (DABCO) as a cheap and readily available donor, furnishing a variety of di(hetero)aryl and aryl/alkyl chalcogenides in good yields. The method is scalable, features a broad scope with good yields, and operates under open‐to‐air conditions. The photoinduced chalcogenation technology is suitable for late‐stage functionalizations and disulfide bioconjugations and facilitates access to biologically relevant thioesters, dithiocarbamates, sulfoximines, and sulfones. Moreover, the method applies to synthesizing diverse pharmaceuticals, such as vortioxetine, promazine, mequitazine, and dapsone, under amenable conditions. [ABSTRACT FROM AUTHOR]

This article investigates late twentieth‐century Corsican nationalism through the lens of gender, drawing attention to how women have sought to play an active and creative role in the movement. Through a series of interviews with female nationalist militants, this article will focus on what belonging to the nationalist movement meant to Corsican women. Gender relations within the nationalist movement reflected the changes taking place in a society fluctuating between tradition and modernity. [ABSTRACT FROM AUTHOR]

We successfully synthesized trifluoromethylated β-ketosulfones via the reaction of vinyl triflates with alkenes employing aqueous sulfurous acid as an external source of SO2. The PhSSPh/photoinitiated reaction with vinyl triflates that contain electron-deficient groups or halogens did not show any base-related effects, whereas the radical reaction was impeded in the absence of a base in the case of vinyl triflates generated from phenylacetylenes. [ABSTRACT FROM AUTHOR]

Steroidal–nitroxide hybrid molecules and non-radical controls were synthesised in good yields using simple carbodiimide coupling. An unexpected product arose from reactions between the nitroxide moiety and the solvent THF. Methoxyamine derivatives of the nitroxide drug hybrids were produced using Fenton chemistry without side reactions occurring on the steroid. The hybrid compounds bind to the glucocorticoid receptor and are relevant for the study of radical biological chemistry and redox-related disease processes. [ABSTRACT FROM AUTHOR]

A photochemical protocol for the alkylation of diazines (pyrimidines, pyrazines, and pyridazines) with N -(acyloxy)phthalimides has been developed. The process is facilitated by the presence of triethylamine under irradiation with 427–390 nm light; this enables rapid cross-coupling reactions to construct a wide range of alkylated diazines. [ABSTRACT FROM AUTHOR]

Visible light‐mediated photocatalytic approach for the radical functionalization of alkenes bearing the fluorinated aryl sulfide fragment is described. The process occurs in the presence of organic photocatalyst using sulfinates as sources of radicals. The key step of the reaction is the intramolecular 1,4‐migration of the polyfluoroaryl group. In the reaction, three new bonds are formed (two C−C and one C−S bond). The decisive role of fluorine atoms in the reaction efficiency was confirmed by DFT calculations. [ABSTRACT FROM AUTHOR]

British Muslim volunteers in Syria have been variously cast as humanitarians, activists, and—under the suspicious gaze of the war on terror—disguised militants. Yet many volunteers frame their efforts as attempts at iṣlāḥ (reform, repair, rectification). What is the ethicopolitical life of iṣlāḥ, a multivalent concept in the Islamic tradition, in a landscape marked by war and international relief efforts? Considered ethnographically, iṣlāḥ organizes heterogeneous practices, including charitable giving, political defiance, and ethical contestation. It is thus irreducible to either (religious) charity or to its oft‐purported opposite, (political) solidarity. Further, it reveals the embedded secularity of such oppositions, which shapes the reasoning of both the British security state and social scientific commentary. [ABSTRACT FROM AUTHOR]

• Contracting skeletal muscles generate reactive oxygen species (ROS) from several locations with the cell. • Although numerous ROS exist, hydrogen peroxide is recognized as a key ROS player in redox control of biological signaling. • Contraction-induced ROS production triggers signaling pathways regulating mitochondrial biogenesis and the expression of numerous genes expressing mitochondrial proteins and antioxidant enzymes. • Growing data indicate that exercise-induced ROS production is essential to achieve the full benefit of exercise-induced adaptation in skeletal muscles. The discovery that contracting skeletal muscle generates reactive oxygen species (ROS) was first reported over 40 years ago. The prevailing view in the 1980s was that exercise-induced ROS production promotes oxidation of proteins and lipids resulting in muscle damage. However, a paradigm shift occurred in the 1990s as growing research revealed that ROS are signaling molecules, capable of activating transcriptional activators/coactivators and promoting exercise-induced muscle adaptation. Growing evidence supports the notion that reduction-oxidation (redox) signaling pathways play an important role in the muscle remodeling that occurs in response to endurance exercise training. This review examines the specific role that redox signaling plays in this endurance exercise-induced skeletal muscle adaptation. We begin with a discussion of the primary sites of ROS production in contracting muscle fibers followed by a summary of the antioxidant enzymes involved in the regulation of ROS levels in the cell. We then discuss which redox-sensitive signaling pathways promote endurance exercise-induced muscle adaptation and debate the strength of the evidence supporting the notion that redox signaling plays an essential role in muscle adaptation to endurance exercise training. In hopes of stimulating future research, we highlight several important unanswered questions in this field. [Display omitted] [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Latin American & Caribbean Studies (Routledge) is the property of Routledge and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The social reintegration of terrorism-related convicts in Europe is a pressing issue. Public opinion can play an essential role in this by making it easier or more difficult to implement (and succeed with) social reintegration strategies. Considering the media's influence on shaping public opinions, attitudes, and social representations, the present research offers a case study by reviewing a decade (2011–2022) of media coverage of the social reintegration of terrorism-related convicts in the seven most read national daily newspapers in France. Results reveal that the topic is very little covered, with 395 newspaper articles published over a decade, and mostly discussing deradicalization, specifically, rather than social reintegration at large. Cluster analysis via Reinert's method reveals that when the topic is discussed it revolves around political and security management (political discourse and security measures), target population (radical Muslims and returnees), and tertiary prevention programs (programs in prison and open settings). A time series analysis of clusters shows their chronological evolution. These findings and their implications for generating (mis)trust in the social reintegration of terrorism-related convicts amongst the general public are discussed. [ABSTRACT FROM AUTHOR]

Organic radicals are gaining significant interest in luminescent materials due to their unique properties, which present unprecedented opportunities for innovation across various fields, from display technology to biomedical applications. However, addressing challenges related to stability and low fluorescence efficiency is crucial to unlocking their full potential for practical applications. Polymerization has emerged as an effective strategy to enhance intra‐ and interchain through‐space interactions, enabling the creation of stable luminescent radicals with excellent processing and multifunctional properties. This concept emphasizes the strategic use of polymerization in designing and synthesizing stable main‐chain and side‐chain radical polymers. This approach not only broadens the scope of stable radicals but also improves their luminescence properties as photofunctional materials. [ABSTRACT FROM AUTHOR]

Selective C−F bond activation through a radical pathway in the presence of multiple C−H bonds remains a formidable challenge, owing to the extraordinarily strong bond strength of the C−F bond. By the aid of density functional theory calculations, we disclose an innovative concerted electron‐fluoride transfer mechanism, harnessing the unique reactivity of Lewis base‐boryl radicals to selectively activate the resilient C−F bonds in fluoroalkanes. This enables the direct abstraction of a fluorine atom and subsequent generation of an alkyl radical, thus expanding the boundaries of halogen atom transfer reactions. [ABSTRACT FROM AUTHOR]

Aryl‐chlorides and ‐fluorides are common building blocks, but their use in synthesis is limited by the high stability of their Ar−X bonds. The generation of aryl radicals via activation of strong Ar−X bonds is possible through the irradiation of tailor‐made organic anions, which become reductants stronger than lithium metal. We report that the combination of visible light with the cheap diphenylacetic acid dianion is an even better tool, showing excellent activity across a variety of complex substrates and providing opportunities for late‐stage drug modification. Ar−X bonds are chemoselectively activated in the presence of more easily reducible functions, such as Alk‐Cl ones and carbonyl groups. These results pave the way to original synthetic strategies that would be otherwise considered impossible. [ABSTRACT FROM AUTHOR]

The development of small organic molecules that can convert light energy into chemical energy to directly promote molecular transformation is of fundamental importance in chemical science. Herein, we report a zwitterionic acridinium amidate as a catalyst for the direct functionalization of aliphatic C−H bonds. This organic zwitterion absorbs visible light to generate the corresponding amidyl radical in the form of excited‐state triplet diradical with prominent reactivity for hydrogen atom transfer to facilitate C−H alkylation with a high turnover number. The experimental and theoretical investigations revealed that the noncovalent interactions between the anionic amidate nitrogen and a pertinent hydrogen‐bond donor, such as hexafluoroisopropanol, are crucial for ensuring the efficient generation of catalytically active species, thereby fully eliciting the distinct reactivity of the acridinium amidate as a photoinduced direct hydrogen atom transfer catalyst. [ABSTRACT FROM AUTHOR]

We report here a novel family of ylidic P‐heteroarenes (P1–P6), structurally featuring unique phosphonium cyclopentadienylide (P−Cp)‐fused π‐skeletons and synthetically prepared via an unexpected one‐pot [2+3]/[3+3] phospha‐annulation reaction. While the facile and modular synthesis allows the fine‐tuning of their optical absorptions and redox properties, single‐crystallographic and theoretical analysis of these P‐heteroarenes further reveal that the fusion of P−Cp moiety leads to substantial intramolecular charge‐separated features with high ylidic character values of up to 84 %. Benefitted from such dipolar structures, these P‐heteroarenes not only allows stepwise electrophilic substitution reaction for further structural π‐expansions, but also exhibit excellent nonlinear optical (NLO) responses and optical limiting (OL) performances comparable to or exceed those of C60. As a model compound, the persistent radical‐anion salt of P5a was also prepared through chemical reduction, thus offering valuable insights into the electronic structures of reduced P‐ylidic species. Our work not only established a highly efficient synthetic method toward new P‐heteroarenes, but also provide fundamental understanding of those fused‐ring ylidic P‐heterocycles with promising NLO/OL applications. [ABSTRACT FROM AUTHOR]

Comprehensive Summary Herein, we describe a direct route for the synthesis of 3‐gem‐difluorovinyl lactams through Zn‐mediated reductive hydrodehalogenation. Importantly, by using inexpensive deuterium oxide (D2O), the high value‐added vicinal dideuterated gem‐difluoroalkenes with excellent deuterium (D) incorporation were prepared. Mechanism studies indicated a successive single electron transfer process: the reaction initially undergoes hydrodechlorination to give the intermediate α‐trifluoromethylidene lactams, which are then activated by the in‐situ generated zinc cations and reduced to the desired product via hydrodefluorination. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Traditional reduction coupling reactions of two bromides typically rely on transition metal catalysis. Here, we introduce the development of a visible‐light catalytic direct reduction coupling reaction between α‐CF3‐alkyl bromides and alkynyl bromides to access valuable organic frameworks. Our research confirms the excellent compatibility of this reaction with various functional groups, which could be used to modify the substrate with biologically active molecular fragments. Mechanistic investigations, including control experiments, fluorescence quenching studies, and light‐switching experiments, have provided insights into the reaction mechanism. This study paves the way for the application of visible‐light catalysis in diverse synthetic transformations, offering a sustainable and efficient approach to organic synthesis. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Traditional reduction coupling reactions of two bromides typically rely on transition metal catalysis. Here, we introduce the development of a visible‐light catalytic direct reduction coupling reaction between α‐CF3‐alkyl bromides and alkynyl bromides to access valuable organic frameworks. Our research confirms the excellent compatibility of this reaction with various functional groups, which could be used to modify the substrate with biologically active molecular fragments. Mechanistic investigations, including control experiments, fluorescence quenching studies, and light‐switching experiments, have provided insights into the reaction mechanism. This study paves the way for the application of visible‐light catalysis in diverse synthetic transformations, offering a sustainable and efficient approach to organic synthesis. [ABSTRACT FROM AUTHOR]

In this work, silyl ethers of phenols and alcohols have been successfully prepared and tested as neutral carbon (silicon) centered radical precursors. The organophotocatalyzed oxidation (by the Fukuzumi catalyst) of these ethers caused the cleavage of a C−Si (or a Si−Si) bond for the release of the desired radical to be used for the forging of C(sp3) −C(sp3) (or C(sp3) −Si) bonds via a Giese reaction. [ABSTRACT FROM AUTHOR]

Functionalized arenes, such as aniline and phenol derivatives, are important structures in natural products, drug molecules, and functional materials. Thus, the development of methods for the efficient synthesis of functionalized arenes from different precursors under mild conditions have been a long‐term topic in organic synthesis and related areas. To date, great efforts have been devoted the Ar−X bond‐forming processes from aromatic precursors. In addition, synthesis of functionalized arenes from aliphatic architectures represents an attractive yet challenging alternative to access functionalized arenes, which construct aromatization during the reaction process along with the formation of C−X bonds. Recently, a new strategy for functionalized arenes from non‐aromatic precursors enabled by radicals has received considerable attention and represents a new direction to access functionalized arenes from broader precursors at room temperature. [ABSTRACT FROM AUTHOR]

Carbohydrates constitute the largest source of biomass on Earth, but their synthetic modification is challenging due to their high content in oxygen functionalities. The site‐ and stereoselective modification of native sugars is a definite goal of glycochemistry research. Recent efforts to bypass the need for protecting groups, leveraging selective activation through photochemical mechanisms for site‐selective C−C bond formation from native sugars, are likely to largely impact all glycochemistry‐related areas. Davis, Koh, and co‐workers have recently presented their use of photocatalysis to develop a “cap and glycosylate” approach for the site‐ and stereoselective C‐glycosylation of native sugars. A modernized direct radical functionalization of in situ formed thioglycoside using photocatalysis was used in the synthetic manipulation of unprotected carbohydrates. This allowed reaching complex saccharides, and post‐translational modification of proteins. [ABSTRACT FROM AUTHOR]

Acenes, as a class of polycyclic aromatic hydrocarbons, attract considerable attention due to their remarkable nonlinear optical and magnetic properties. The aim of this work was the elucidation of the capability of radical-substituted acene derivatives to undergo spin-state-switching rearrangements. For this purpose, a series of acene-based (anthracene, pentacene, heptacene) molecules bearing fluorenyl and tert-butyl-nitroxyl radicals were investigated through comprehensive quantum chemical modeling of their electronic structures, isomerization and magnetic properties. A possible mechanism of the transformation of the closed-shell folded isomer into the biradical twisted structure of the bis-fluorenyl anthracene has been ascertained by applying the procedure of searching for the Minimum Energy Crossing Point. The conditions favoring the occurrence of spin-state-switching in such classes of polycyclic aromatic hydrocarbon derivatives have been formulated. By varying the size of an acene core and the type of radical substituent, the compounds capable of changing their magnetic properties have been revealed. Considering the unique features of radical-bearing acene-based derivatives, the proposed molecules can be used as functional materials in photonics and electronics. [ABSTRACT FROM AUTHOR]

Radical democrats highlight the emancipatory potential of citizenship rights insofar as they enable the enactment of political subjectivity by those who lay claim to them. However, the conjuncture(s) within which citizenship rights originate (and are rearticulated) matters for the kind of political subjectivity they afford. This article traces the articulation of citizenship rights in Britain in relation to three historical conjunctures: 1948 (in which the introduction of the status of Citizen of the UK and its Colonies (CUKC) coincided with imperial decline); 1981 (in which the status of CUKC was displaced by that of British Citizen as Britain reinvented itself as a nation-state) and; 2012 (in which the hostile environment for irregular migrants was instituted amidst sustained austerity for its citizens). This conjunctural analysis enables us to recognise the good character requirement (that underpins the deportation of Black Britons to former colonies) and the Right to Rent (that deputises immigration control to landlords) as after rights of the CUKC, that is, rights depleted of their political significance as belonging to a free and equal member of the polity. This, I argue, significantly limits any emancipatory potential that enacting citizenship rights in Britain might otherwise enable. [ABSTRACT FROM AUTHOR]

This paper argues that there is need for current efforts to reintegrate youth militants in the Niger Delta of Nigeria into normal community life to be anchored on a thorough understanding of the peculiar agency of youth and the socio-cultural challenges of post-conflict reintegration. Such efforts should also take cognisance of the complex nature of the problem. The paper contends that while the on-going amnesty programme in the region has achieved partial success, it was founded on a parochial philosophy, which creates a booming economic environment for the managers. Therefore, it recommends that the initiative should be anchored on both a thorough understanding of the youth as social agency and the deleterious impact of the conflict on ideal socio-cultural norms of expectations and roles among different generations of the population in the region. In effect, a proper sociological framing and nuancing of the programme would appear imperative for sustainable peace in the region. [ABSTRACT FROM AUTHOR]

The article considers the pivotal organizing role of the revolutionary paper Congress Militant for the Marxist Workers' Tendency of the African National Congress from the late 1980s to the mid-1990s, a period characterized by mass popular struggles against apartheid, violence, and political negotiations. Congress Militant was instrumental in shaping the internal life of the Tendency, from being a space of reportage of local struggles and political analyses to contributing to the development of a community of revolutionary cadres who belonged to national and international organizations. It was also the principal public vehicle for the propagation of the Tendency's politics, serving as a tool of intervention in numerous campaigns and in recruitment. As such, the paper offers a window into the history of the changing politics of one socialist organization during the tumultuous years of the early 1990s in South Africa, including its criticisms of the compromises made by the ANC leadership during the negotiations. [ABSTRACT FROM AUTHOR]

This article situates racial capitalism as a historical-theoretical framework to generate new and alternative theory on the question of Palestine. It argues that the genocidal assault on Gaza must be understood as the clearest expression of the logic of racial capitalism and the terrain upon which we must generate theory and strategy able to dismantle Zionism, colonialism and Imperialism. Many of the critiques of Zionism deploy frameworks of apartheid, understood by radicals in South Africa as a social structure reproduced by racial capitalism. It was understood that such a system could only be effectively dismantled through a national liberation project which understood race, class, capital and Imperialism as a single contradiction which must be overthrown as a totality. Similarly, earlier theorists within the Palestinian anti-colonial struggle, such as Fayez Sayegh, understood Zionist settler colonialism as an outpost of Western Imperialism. By tracing the emergence of racial capitalism within the South African anti-apartheid struggle and the similarities between the white minority regime and Zionism, this article acts as a point of departure to drawing together histories of the Black radical tradition and the Palestinian struggle in crafting radical theory relevant for our present moment. [ABSTRACT FROM AUTHOR]

The use of organic molecules as photosensitizers in photoredox catalysis is an attractive research field as it has the potential to replace conventionally used photosensitizers, which are based on rare metals. In the context of light‐driven hydrogen evolution catalysis, the radical formation of two perylene monoimide dyes (PMIs) was studied by means of electron paramagnetic resonance (EPR) and UV/Vis spectroscopy. The PMIs were reduced and oxidized both photochemically and electrochemically to study the changes in absorption and EPR signature. A distinct differentiation between the two PMIs as well as a comparison between the oxidative and reductive processes can be made by EPR measurements. UV/Vis measurements showed different features under redox conditions. This study addresses a gap in understanding the radical intermediate formation during photocatalytic processes. [ABSTRACT FROM AUTHOR]

A growing line of research examines causes and consequences of militant group competition. However, empirical work on these topics has limitations. Most quantitative research uses relatively rough proxies for competition, such as counts of groups in a country. Other work uses dichotomous indicators, ignoring the intensity or degree of rivalries. Additionally, many studies examine either terrorist organizations or rebel groups, overlooking cross-type rivalry (e.g., terrorist vs. rebel). We address these issues by introducing time-varying dyadic rivalry data on hundreds of groups – rebels, terrorists, and pro-government militias – in Africa and Asia, 1990-2015. Rivalry levels include denouncements, threats, and violence. After presenting the data, we test the "outbidding" hypothesis: the notion that inter-organizational competition leads to more terrorism. This argument has found support in qualitative analyses, but quantitative tests using rivalry proxies show mixed results. Using our data we find support for the hypothesis. We conclude with research questions that could be addressed with the data. [ABSTRACT FROM AUTHOR]

In this study, gas–liquid discharge plasma excited by nanosecond pulsed voltage is used to efficiently remove tiamulin (TIA) from water. The discharge produces a large number of reactive species (H2O2, OH radicals, NO3−, etc.) that can attack the TIA molecules. The effects of peak pulse voltage, initial TIA concentration, gas composition, and the addition of ferrous sulfate and persulfate on TIA removal were mainly investigated. The results showed that the oxygen plasma could approach 100% removal within 30 min of treatment time. The addition of the catalyst increased the TIA removal efficiency by approximately 15% during the 10‐min discharge treatment time. The toxicity of 12 intermediates was analyzed and the degradation mechanism of TIA was investigated. [ABSTRACT FROM AUTHOR]

Tetrahydropyridazines constitute an important structural motif found in numerous natural products and pharmaceutical compounds. Herein, we report an aminoacylation reaction of alkenes that enables the synthesis of 1,4,5,6‐tetrahydropyridazines through cooperative N‐heterocyclic carbene (NHC) and photoredox catalysis. This approach involves the 6‐endo‐trig cyclization of N‐centered hydrazonyl radicals, generated via single‐electron oxidation of hydrazones, followed by a radical–radical coupling step. The mild process tolerates a wide range of common functional groups and affords a variety of tetrahydropyridazines in moderate to high yields. Preliminary investigations using chiral NHC catalysts demonstrate the potential of this protocol for asymmetric radical reactions. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Catalytic and green strategies for the synthesis of privileged scaffolds are synthetically appealing. We now report a radical‐polar crossover (RPC)‐enabled three‐component cyclization of bromodifluoroalkyls with enaminones and 6‐aminouraciles via a visible‐light‐induced domino cyclization. The reaction exhibited a broad substrate scope (> 40 examples) including complex molecules, which highlighted the utility of this strategy for the construction of a library of bioactive analogs. [ABSTRACT FROM AUTHOR]

Copyright of Environmental Science & Technology (10036504) is the property of Editorial Board of Environmental Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

De Luca's A Dissenting Word (2015) – his essay-length self-defense against charges brought by the Italian state in response to his statements made in support of the No TAV movement in Italy's Val di Susa – was in part the inspiration for the present collection of essays. The interview that follows focuses on the definition and application of De Luca's concept of 'contrarian speech' in light of subsequent events, particularly the rise of a militant Right in Italy and beyond. [ABSTRACT FROM AUTHOR]

This research investigates methylene blue as a high-performance photocatalyst in the photo-oxidation conversion of alcohols to aldehydes. The present study investigates the optimal conditions for the solvent effect, catalyst, and oxidant amount. The objective is to identify the most practical combination of these factors to optimize the desired outcome of the experiment. The notable characteristics of this transformation include its gentle conditions, the use of a metal-free organic dye as a photocatalyst, and TBHP's dual function as both a radical initiator and a means for regenerating the photocatalyst. This research provides valuable insights into the potential of methylene blue as a high-performance photocatalyst in the photo-oxidation reaction of alcohols, paving the way for more efficient photocatalytic processes. [ABSTRACT FROM AUTHOR]

Where cross‐border sanctuaries enable rebels to marshal external support, classical theories of counterinsurgency extol the strategic value of border fortification. By sealing borders, counterinsurgents can erode transnational militants' resources, degrading the quality of rebellion. Extending resource‐centric theories of conflict, I posit a fortification dilemma inherent in this strategy. Externally supplied rebels can afford conventional attacks and civilian victimization. When border fortifications interdict their foreign logistics, insurgents compensate by cultivating greater local support. In turn, rebels prefer more irregular attacks and cooperative relations with civilians. Hence, counterinsurgent border fortification trades off reduced rebel capabilities for greater competition over local hearts and minds. I test this theory using declassified microdata on border fortification and violence in Iraq. Results highlight the central link between border control and cross‐border militancy, and show how governments can contest the transnational dimensions of civil wars, such as external rebel sponsorship. [ABSTRACT FROM AUTHOR]

Activating dihydrogen, H2, is a challenging endeavor typically achieved using transition metal centers. Pure main‐group compounds capable of this are rare and have emerged in recent decades. These systems rely on synergistic donor‐acceptor interactions with H2’s antibonding σ* and bonding σ orbital. An alternative (hydrocarbon) radical‐mediated activation is problematic because the H−H bond is stronger (104.2 kcal mol−1) than most C−H bonds. Here, we explore using the phenyl radical to tackle this, forming benzene with a C−H bond energy (112.9 kcal mol−1) that provides a thermodynamic driving force. We mainly observe a benzene‐HI complex upon photolysis of iodobenzene in an H2‐doped neon matrix at 4.4 K despite a barrier of 7.6 kcal mol−1, while phenyl radical forms in case of the heavier D2 isotopologue. When D2 molecules are allowed to diffuse, mono‐deuterated benzene accumulates within hours. Computations using path integral‐based instanton theory highlight that primarily the transferred hydrogen atom is moving during the reaction which greatly increases the tunneling probability. In excellent agreement with the experimental results, we predict significant tunneling rate constants for both isotopologues, H2 and D2, featuring a strong kinetic isotope effect of up to four orders of magnitude at the lowest temperatures. [ABSTRACT FROM AUTHOR]

In this paper, we review the concept of synergistically using ultrasonic sonochemistry in combination with heterogeneous catalysis, to selectively perform condensed phase chemical transformations. Through specific examples, we highlight that ultrasound induced cavitation bubbles not only provide local high temperature and pressure conditions for initiating chemical reactions but also improves heat, mass and charge transfer characteristics in the system. We also show that sonocatalysis can alter reaction mechanisms and open new activation and reaction pathways that are not intuitive to thermocatalysis. Computational chemistry tools are introduced and are combined with sonocatalysis experimental studies to demonstrate that, in‐situ generated radicals propelled into the bulk liquid solution upon bubbles implosion can be stabilized by catalyst surfaces, while creating active sites for unique reactions during heterogeneous sonocatalytic chemistry. We also report recent examples of condensed phase sonocatalysis applications, including pollutant degradation, chemical and pharmaceutical synthesis and biomass upgrading, and provide mechanistic insights into the process. [ABSTRACT FROM AUTHOR]

Allylic sulfones are valuable motifs due to their medicinal and biological significance and their versatile chemical reactivities. While direct allylic C−H sulfonylation represents a straightforward and desirable approach, these methods are primarily restricted to terminal alkenes, leaving the engagement of the internal counterparts a formidable challenge. Herein we report a photocatalytic approach that accommodates both cyclic and acyclic internal alkenes with diverse substitution patterns and electronic properties. Importantly, the obtained allylic sulfones can be readily diversified into a wide range of products, thus enabling formal alkene transposition and all‐carbon quaternary center formation through the sequential C−H functionalization. [ABSTRACT FROM AUTHOR]

The use of sulfonium salts in organic synthesis has experienced a dramatic increase during the last years that can arguably be attributed to three main factors; the development of more direct and efficient synthetic methods that make easily available sulfonium reagents of a wide structural variety, their intrinsic thermal stability, which facilitates their structural modification, handling and purification even on large scale, and the recognition that their reactivity resembles that of hypervalent iodine compounds and therefore, they can be used as replacement of such reagents for most of their uses. This renewed interest has led to the improvement of already existing reactions, as well as to the discovery of unprecedented transformations; in particular, by the implementation of photocatalytic protocols. This review aims to summarize the most recent advancements on the area focusing on the work published during and after 2020. The scope of the methods developed will be highlighted and their limitations critically evaluated. [ABSTRACT FROM AUTHOR]

Being a low‐toxic and hydrophilic representative of TAM, OX063 has shown its suitability for in‐vivo and in‐cell EPR experiments and design of spin labels. Using 13C labeling, we investigated the course of oxidative degradation of OX063 into quinone‐methide (QM) under the influence of superoxide as well as further thiol‐promoted reduction of QM into TAM radical, which formally corresponds to substitution of a carboxyl function by a hydroxyl group. We found these transformations being quantitative in model reactions mimicking specific features of biological media and confirmed the presence of these reactions in the blood and liver homogenate of mice in vitro. The emergence of the trityl with the hydroxyl group can be masked by an initial TAM in EPR spectra and may introduce distortions into EPR‐derived oximetry data if they have been obtained for objects under hypoxia. 13C labeling allows one to detect its presence, considering its different hyperfine splitting constant on 13C1 (2.04 mT) as compared to OX063 (2.30 mT). The potential involvement of these reactions should be considered when using TAM in spin‐labeling of biopolymers intended for subsequent EPR experiments, as well as in the successful application of TAM in experiments in vivo and in cell. [ABSTRACT FROM AUTHOR]

A direct visible‐light‐promoted radical‐triggered tandem cyclization of 1,7‐diene systems with cyclic sulfonium salts by using copper(I)‐based complexes as photoredox catalyst is developed. With this approach, a variety of sulfur‐containing polycyclic derivatives are prepared through alkylation/6‐exo‐trig cyclization/5‐exo‐trig cyclization of 1,7‐diene systems under mild conditions. In addition, the photoinduced copper‐catalyzed ring‐opening of cyclic sulfonium salts provides the alkyl radical intermediates, which prefers addition to the C−C double bond that connected to the aromatic ring rather than the electron‐deficient vinyl in 1,7‐dienes. Moreover, oxidation of the desired sulfur‐containing polycyclic products provides a strategy for the preparation of remote nitrogen‐fused polycyclic substituted sulfoxide or sulfone‐containing derivatives. [ABSTRACT FROM AUTHOR]