bluuebunny/crossref_metadata_2025 huggingface dataset:
Hydroformylation – Industrial
Authors: Kohlpaintner Christian
Published: December 2022

After its discovery in 1938 the hydroformylation reaction soon became the most successful example for a homogeneously catalyzed industrial process, with an estimated installed annual capacity of almost 8 million tons in 2000. After the first plant start‐up in 1942, several companies developed cobalt‐based high pressure oxo processes. Shell and others developed high pressure processes with unmodified rhodium catalysts during the mid‐sixties. The introduction of ligand‐modified rhodium catalysts in 1976 allowed for smoother reaction conditions (pressure and temperature) and better selectivities toward linear products. Further milestones include usage of water‐soluble (Ruhrchemie/Rhone‐Poulenc Process, 1984) and phosphite‐modified rhodium catalysts (Union Carbide Mark IV, 1995). Both processes have their advantages in the catalyst/product separation (RCH/RP) or the improved yield of linear products (UCC Mark IV). All processes are discussed in depth in the article.
Hydrogenation – Heterogeneous
Authors: Gallezot Pierre
Published: December 2022

The development of heterogeneous hydrogenation catalysis started at the beginning of the twentieth century. It is still the most developed field of catalysis in terms of the varieties of catalysts and applications. This article gives a survey in two parts of all the aspects of heterogeneous catalysis dealing with the hydrogenation of organic molecules. The first deals with all the fundamental aspects including molecular mechanisms, kinetics of reactions, catalyst structure–activity/selectivity relationships, and all the physicochemical factors affecting the rate and selectivity of hydrogenation reactions. The second part deals with more practical aspects such as the description of the different types of hydrogenation catalysts, on their selection to achieve a specific hydrogenation reaction, and of their utilization in reactors.
Isotope Methods – Homogeneous
Authors: Bullock R. Morris , Bender Bruce R.
Published: December 2022

The article reviews the use of isotopes to determine mechanisms of homogeneously catalyzed reactions. Kinetic isotope effects (KIEs) and equilibrium isotope effects (EIEs) on single steps as well as those on complete catalytic cycles are considered. Coverage includes EIEs and KIEs for the addition and elimination of H2and hydrocarbons to metal complexes. Isotope effects for proton, hydrogen atom, and hydride transfer to and from metal complexes, along with insertions into metal–hydrogen bonds, are discussed in detail. Isotope effects on olefin polymerization, oxidation, hydrogenation, and hydroformylation are discussed. Isotope effects on spectroscopic properties are included by way of discussion and interpretation.
Isotope Methods in Catalysis – Biological
Authors: Schowen Richard L. , Schowen K. Barbara
Published: December 2022

Isotopic methods in the study of biocatalysis are chiefly used to characterize the mechanisms by which enzymes catalyze their target reactions. The techniques in use include tracer methods, by which the positions of individual atoms in a starting molecule are traced in downstream intermediates or products; exchange methods, in which isotopic mixing between distinct pools such as the solvent and enzyme‐bound intermediates is measured in order to test mechanistic hypotheses; and kinetic isotope effects, in which the relative rates of reaction of different isotopes of the same element are measured to identify rate‐limiting steps and determine transition‐state structures and other mechanistic information. Tracer and exchange methods are illustrated but, not being subject to easy generalization, are not treated in detail. The bulk of the article is devoted to kinetic isotope effects in the study of biocatalysts.
Kinetics of Catalyzed Reactions – Homogeneous
Authors: Espenson James H.
Published: December 2022

Catalysts are not static entities, instead they are species that repetitively recycle through at least two forms, and sometimes more. The catalyst opens a new pathway with a lower Gibbs energy of activation; it does not somehow lower the activation energy of an existing pathway. Certain mathematical approaches to the analysis of data from catalytic kinetics are given. Forms that are useful in practice must allow for the coexistence, at comparable concentration, of these three species: the catalyst (C), its complex with substrate (C·S) and very likely with product (C·P). The steady‐state approximation often provides a tractable solution, although its form may require one to rely on initial‐rate method rather than integration of the reaction progress over its entire time course. A more precise solution can be obtained by methods employing numerical integration or its equivalent, programs for which can be downloaded from the Internet. Some catalytic systems require the consideration of inhibitory phenomena, and the case of competitive, noncompetitive, and uncompetitive inhibition are presented. Data from the very earliest stages of a reaction, before product has accumulated, can provide rate constants for the important catalytst–substrate binding phase.
Kinetics of Catalyzed Reactions – Biological
Authors: McDonald Andrew G. , Tipton Keith F.
Published: December 2022

An understanding of the kinetic reaction pathways (mechanisms) followed by enzymes is an essential prerequisite to understanding how enzymes might function in their normal complex metabolic enviroments within cells and tissues. It is also important for the interpretation of the behavior of mutant enzymes, the design and behavior of enzyme inhibitors for drug use, and the meaningful comparison of enzyme activities between laboratories, tissue, and individuals. This account describes the kinetic behavior of enzymes that catalyze reactions involving one or more substrates, the mechanisms that may be followed and the application of inhibition and other approaches to determining the mechanism followed. Systems obeying simple saturation kinetics are described together with those that may lead to more complex behavior. Enzyme classification and nomenclature are outlined and possible complexities in the initial‐rate behavior of enzyme‐catalyzed reactions and in the dependence of rate upon enzyme concentration are also described along with accepted standards for the expression of enzyme activities.
Methanation
Authors: Tomoyuki Inui
Published: December 2022

Methanation, i.e., catalytic hydrogenation of carbon oxides (CO and CO2), especially methanation of CO, has been studied extensively from the beginning of the twentieth century. Focus of academic and indusrial interests of methanation has shifted during the long period, and the history of methanation can be divided into three stages. In the first stage, methantion of CO had been studied as a typical catalytic reaction of simple molecules associated with Fischer–Tropsch reaction, which aims at the synthesis of higher carbon‐number hydrocarbons. In the second stage, methanation was applied to the production of high caloric gaseous fuel from coke oven gas and/or syngas, called SNG process. Methanation was also applied to a chemical heat pipe system, so‐called FVA–ADAM process, which aimed to establish an energy saving technology. In the third stage, the knowledge of methanation was extended to solve the problem of global warming with CO2. Especially, design of the catalyst for ultrarapid methanation of carbon oxides contributes in a practical way to solve global warming owing to CO2accumulation. Both catalyst components and pore structure of the catalyst support are significant factors that contribute to whether a catalyst may be used for ultrarapid methanation. Simultaneous methanation of CO and CO2is also described.
Michael Addition
Authors: Christoffers Jens
Published: December 2022

The Michael reaction is defined as the conjugate 1,4‐addition of carbon nucleophiles to acceptor‐substituted CC bonds. Enolates of β‐dicarbonyl compounds represent typical nucleophiles in this classical base‐catalyzed CC‐bond‐forming reaction, yielding 1,5‐dicarbonyl compounds as products. In some cases, metal catalysts as simple as FeCl3 6 H2O can be applied, avoiding basic reaction conditions and thus resulting in an improved chemoselectivity compared with base catalysis. The Michael reaction can be performed in an intramolecular or vinylogous fashion, and is known as an elementary step in several reaction sequences. In most cases, Michael reaction products have at least one new stereogenic center. In order to achieve asymmetric reactions, chiral auxiliaries, chiral Brönstedt bases, or metal complexes bearing chiral ligands have been reported as catalysts for the Michael reaction.
Molybdendium Enzymes and Models
Authors: Neiter Burgmayer Sharon
Published: December 2022

Enzymes whose catalytic reactions occur at a molybdenum center are described. These molybdoenzymes are found in organisms throughout the entire kingdom of life, from simple bacteria to humans, and are critical to the ecosphere. With only one exception, these approximately 40 enzymes catalyze reactions where an oxygen atom is added to or removed from the biological substrate. This generalization explains the terminology applied to these enzymes, which are variously called molybdenum hydroxylases, oxotransferases, and oxo–molybdenum enzymes. A survey of the four main families of molybdenum enzymes and a list of selected molybdoenzymes is provided. A brief discussion of the special dithiolene ligand called molybdopterin that is bound to molybdenum (and tungsten) in all of these enzymes is given, highlighting its structure and associated nomenclatural difficulties. Representative examples of mechanisms are illustrated. A considerable progress in understanding the special attributes of molybdenum and its associated ligand has been accomplished through studies of smaller molecules, called
analogue
or
model
systems. Several key examples of these model systems are described. These provide independent confirmation of the reasonableness of proposed mechanistic steps as well as point to unique aspects of molybdenum in the enzymes not easily mimicked by synthetic systems.
Nitrile Hydratase
Authors: Shearer Jason , Kovacs Julie A.
Published: December 2022

Nitrile hydratases (NHases) are metalloenzymes, found in soil bacteria, first isolated from toxic wate sites, which catalyze the hydration of nitrile to amides. These contain either a mononuclear non‐heme Fe
3+
or a non‐corrinoid Co
3+
. Initial spectroscopic studies demonstrated that both the metal centers are low spin (
S
= 1/2 for Fe
3+
and
S
= 0 Co
3+
). Two crystal structures of Fe‐NHase from
Rhodococcus
R312 have shown that the iron center is ligated by three cysteinates in a
fac
configuration, two amide nitrogens from the peptide backbone, and a hydroxide (active form) or NO (inactive form) in a site
trans
to a cysteinate. The electronic spectrum of the active form of Fe‐NHase is dominated by an intense π‐sulfur‐to‐metal charge transfer band near 700 nm. The EPR and electronic absorption spectra of Fe‐NHase are both substrate‐ and pH‐dependent. NHase has been used industrially in the multi‐kiloton production of commodity amides, has been utilized to a limited extent as a reagent for organic synthesis, and may find use in the field of chemical waste treatment. Model compounds, in combination with biochemical and biophysical techniques, have proven useful in answering fundamental questions concerning NHase, but several key issues remain unresolved. For examle, the mechanism of NHase catalysis remains to be elucidated, and the involvement of low spin, rather than the more reactive high spin metal ions (Co
3+
, Fe
3+
) in these reactions has yet to be explained.
Oxychlorination – Heterogeneous
Authors: Taârit Younès Ben
Published: December 2022

A brief account of the halogenation of organic compounds to manufacture products of practical use, such as halomethanes, chloroaromatics, chloroaliphatics, and vinyl chlorides, is given as an introduction. The production of chlorine, the chief halogenation agent, starting from HCl, a major by‐product, is also briefly reviewed. The Deacon process, particularly its thermodynamic aspects, is surveyed. The oxychlorination of ethene and methane is then covered in depth. The reaction thermodynamics shows its advantage against the plain Deacon. Most of the operating processes use the favourite Cucl
2
‐based catalyst. The role of alkali chlorides is examined. The formation of the complex salt is thought to provide increased mobility and availability of the active species and a more effective reoxidation, an otherwise slow step. Agglomeration of the active species is also prevented owing to appropriate coordination. The overall kinetics are reviewed. The influence of the support is emphasized with respect to stickiness. The nature of the active sites is examined based on spectroscopic and catalytic performance studies. Finally, mechanistic speculations, in line with well‐established schemes in homogeneous catalysis, are offered and potential zeolite‐based catalysts are suggested.
Radicals in Catalysis – Heterogeneous
Authors: Sojka Zbigniew , Giamello Elio , Cristina Paganini Maria
Published: December 2022

Several reactions in heterogeneous catalysis take place via radical intermediates. The present article illustrates the typical aspects of the radical chemistry in heterogeneous catalysis that very often differ from those in the radical chemistry in fluid homogeneous phases because of the role of the surface in the generation, stabilization, and transformation of radical species. The various routes for the formation of radicals on a surface will be taken into consideration including electron transfer, atom transfer, and molecular dissociation. A particular emphasis is given to the electron magnetic resonance techniques, which have the paramount role in the detection and also in the description of the radical species because of their high sensitivity that allows the detection of low abundance species. In the final part of the article some selected examples of heterogeneous catalytic processes involving radical steps will be discussed with particular emphasis on catalytic oxidation on metal oxides.
Selective Oxidation – Homogeneous
Authors: Sheldon R. A. , ten Brink G. J. , Arends I. W. C. E.
Published: December 2022

In the manufacture of fine chemicals there is a considerable pressure to replace traditional oxidation techniques, using stoichiometric quantities of high valent metal salts, with cleaner, catalytic alternatives. This article focuses on homogeneous catalysis of liquid‐phase oxidations employing dioxygen, hydrogen peroxide, or alkyl hydroperoxides as the primary oxidant. Where relevant, heterogeneous equivalents are also discussed. Following a general introduction, which includes a discussion of the different reaction mechanisms and of the design of ligands for oxidation catalysts, the different classes of substrates are discussed. These are alkenes (epoxidation, vicinal dihydroxylation, oxidative cleavage, ketonization, and allylic oxidation), alkanes and alkyl aromatics (side‐chain versus aromatic‐ring oxidation), oxygen‐containing compounds (alcohols, diols, aldehydes, ketones, phenols, and ethers), amines, and sulfur‐containing compounds. A separate section is devoted to asymmetric catalysis (epoxidation and dihydroxylation of olefins, sulfoxidation, and Baeyer–Villiger oxidation).
Selective Oxidation – Biological
Authors: Dunford H. Brian
Published: December 2022

The oxiding properties of metalloenzymes are reviewed. The reactive oxygen‐containing species formed by successive one‐electron reductions of dioxygen to water are discussed. Emphasis is on iron‐containing enzymes and in particular heme enzymes. Details of peroxidase, catalase, cytochrome P450, nitric oxide synthase, guanylate cyclase, and cytochrome c oxidase reactions are summarized. A brief sojourn looks at the role of sulfur, which converts iron‐containing enzymes from oxidation catalysts to reduction catalysts. An example is nitrogenase where iron–sulfur clusters contribute to the molybdenum‐catalyzed reduction of dinitrogen to ammonia. Copper enzymes and in particular copper‐zinc superoxide dismutase are also examined.
Selenium in Biocatalysis
Authors: Lacourciere Gerard M.
Published: December 2022

Selenium has long been considered a toxic element. Its toxicity has been attributed to its incorporation into the amino acids cysteine and methionine in place of sulfur. This incorporation results in an alteration in the structure of proteins which directly affects its function. Today it is well documented that at low concentrations, selenium is an essential element. The discovery of several prokaryotic and eukaryotic proteins that contain selenium as the amino acid selenocysteine or as an unstable perselenide adduct demonstrated that selenium is directly involved in biocatalysis.
Sulfate Activation
Authors: Moura José J. G. , Bursakov Sergey A. , Gavel Olga , Moura Isabel
Published: December 2022

Sulfate is an inert molecule that must be chemically activated before it can be involved in biochemical pathways. This article deals with biological sulfate activation via adenylylation. The activation of inorganic sulfate involves the formation of a “high energy” phosphosulfate anhydride bond in adenosine‐5′‐phosphosulfate (APS) and is catalyzed by the enzyme ATP sulfurylase. A consecutive step, catalyzed by APS kinase, produces another form of activated sulfate: 3′‐phosphoadenosine 5′‐phosphosulfate (PAPS). APS and PAPS are used in the formation of the thiol groups of sulfur containing amino acids and their derivatives, as well as specialized sulfur compounds, and also have other diverse functions.
Shape‐Selective Catalysis – Heterogeneous
Authors: Csicsery Sigmund M. , Kiricsi Imre
Published: December 2022

Molecular sieves have uniform pores. If the pores are small, the fate of the reactants and the probability of forming products are determined by molecular dimensions and configurations as well as by the types of catalytically active sites present. Reactant shape selectivity occurs when some of the molecules in a reactant mixture are too large to enter the pores. Product selectivity occurs when, among all the product molecules formed within the pores, only those with the proper dimensions can diffuse out and appear as products. In restricted transition state type selectivity certain reactions are prevented because the corresponding transition state requires more space than is available inside the pores.

Shape selective processes include acid‐ or base‐catalyzed reactions, oxidations, and reductions. Commercial applications of shape selectivity (1) form desirable isomers instead of undesirable ones, (2) crack undesirable molecules to smaller, easily removable fragments, or (3) avoid undesirable competing reactions such as coking and transalkylation.

Ordered mesoporous materials, pillared layer structures, heteropolyacids, and carbon molecular sieves and nanotubes extend shape‐selective application to reactions of molecules too large to fit in the pores of aluminosilicate zeolites. Designing new molecular sieves and modifying existing ones can amplify shape selective effects and thus help to meet future challenges: diminishing raw material supplies, more stringent environmental regulations, changing fuel requirements, and the desire for more flexible, more economical, and environmentally more friendly processes.
Combinatorial Catalysis – Homogeneous
Authors: Tuba Róbert
Published: December 2022

Combinatorial chemistry is a high throughput experimental technique that has significantly changed the drug discovery process in the pharmaceutical industry and become common practice for drug research. Combinatorial synthesis and rapid screening techniques have been applied to the development of homogeneous catalysts and for the optimization of reaction conditions. In contrast to classical experimental design, well‐designed high throughput screening systems can test more catalysts a week than was previously done in a year. This could lead to significant savings in research and development costs.

This article provides a survey of the most frequently used combinatorial methods and screening systems applied in homogeneous catalysts discovery. Several examples are presented on the identification of most effective homogeneous catalysts for hydrogenation, hydrosilylation, cyclopropanation, epoxidation, etc.
Precipitating Events and Flashpoints
Authors: Owens Peter B.
Published: December 2022

It is often the case that certain critical events can have enormous impacts on the dynamics of collective action. When such events appear to “trigger” or “spark” collective action by convincing potential participants that action is necessary or desirable, or mark a critical turning point in the dynamics of a particular pattern of mobilization, they may be thought of as precipitating events. These events will tend to fall along a varied range of characteristics. Some may be violent and traumatic, such as an assassination or an instance of police brutality, while others may be relatively civil or even celebratory, such as the election of a supported political candidate or the victory of a sports team. Some events may appear to be relatively isolated and singular, while others may occur in a cumulative pattern over time. An event might be planned and executed by movement participants, or be completely unexpected. One event might trigger explosive episodes such as riots, while others might lead to long‐term changes in a cycle of protest, such as shifts in a movement's strategy. Despite such variation, the defining feature of a precipitating event is that it serves as some form of social‐cognitive “trigger” that defines, in part, the forms of collective action that occurs in its wake.
Protest Cycles and Waves
Authors: della Porta Donatella
Published: December 2022

Social movement studies have traditionally stressed
conflict
as a dynamic element in our societies. Social movements are conflictual not only because of their stakes, but also because of their forms of action. Defined in the sociology of social movements as a “resource of the powerless,” protest has been considered as the main repertoire of action – or even the modus operandi – of social movements.
Radical Flank Effects
Authors: Haines Herbert H.
Published: December 2022

Radical flank effects (RFEs) are interactive processes involving radical and moderate factions of social movements and third parties outside those movements. They result in detrimental and/or beneficial impacts of radical group actions upon the reputations and effectiveness of more moderate collective actors – typically social movement organizations. The relative “radicalism” or “moderation” of actors is generally defined in terms of the degree of legitimacy that is imputed to their objectives, rhetoric, and tactics by relevant external audiences. Radical flank effects were first studied systematically by Haines in his investigations of the American civil rights/Black Power movements, but other scholars had made reference to RFE‐like phenomena in earlier works on the civil rights, feminist, labor, and anti‐nuclear movements.
Social Problems and Social Movements
Authors: Best Joel
Published: December 2022

Both the sociology of social movements and the sociology of social problems experienced intellectual revivals that began in the 1970s. The study of social movements shifted from accounting for movements' members' discontent, to an effort to understand why movements succeeded or failed, based on models that emphasized framing, resource mobilization, opportunity structures, and identity politics. Similarly, the study of social problems turned from the analysis of harmful social conditions to an emphasis on the process by which social problems were socially constructed.
ACT UP (AIDS Coalition to Unleash Power)
Authors: Stockdill Brett C.
Published: December 2022

Outraged by the lack of concerted effort to fight the AIDS crisis, queer activists formed the direct‐action AIDS organization ACT UP in 1987. They were enraged because tens of thousands of people, disproportionately gay and bisexual men, had died of AIDS, yet governmental, mass media, medical establishment, and other institutional responses were characterized by homophobia and genocidal neglect. Beginning with the first chapter in New York City in March 1987, activists soon established over 80 chapters in the United States, including Puerto Rico, and over 30 elsewhere, including Australia, Canada, and Europe. ACT UP's repertoire of innovative, confrontational tactics was decisive in publicizing myriad aspects of the HIV/AIDS crisis, increasing government HIV/AIDS budgets, preventing new HIV infections, galvanizing research, reshaping clinical drug trials, securing access to services and treatment for people living with HIV/AIDS, and fighting repressive legislation including calls to quarantine people with HIV/AIDS. ACT UP empowered people living with HIV/AIDS and challenged homophobia, racism, sexism, and other inequalities fueling the AIDS crisis. In the process, the organization ignited gay and lesbian pride, cultivating rebellious queer identities and political action that celebrated sexual difference and envisioned a more just and inclusive world. Most ACT UP chapters declined in the early to mid‐1990s but a few continue to do vital AIDS activism today.
AIDS Activism
Authors: Fillieule Olivier
Published: December 2022

The AIDS epidemic first appeared as a public issue in the USA during the summer of 1981. It was then that the first stories were published in medical journals and in the gay press reporting the emergence of mysterious new illnesses among gay men, and it was the gay community, perhaps to a unique degree, which mobilized first and took part in all aspects of the management of the epidemic. This included the provision of social aid and healthcare to people with AIDS, gay or not, the conduct of research, lobbying for funds and other government intervention, the creation of educational programs, and negotiations with legislators and health insurers.
Anti‐nuclear Movement (Japan)
Authors: Aldrich Daniel P.
Published: December 2022

Japan remains the only nation in the world to have experienced the horrors of atomic weaponry, at Hiroshima and Nagasaki in 1945, but the government initially suppressed public debate on the topic and the postwar occupation authorities temporarily banned research on nuclear power. Thus, there was a lag between the bombings and the start of broader anti‐nuclear movements, which began in the 1950s as a result of widespread anger over the deadly exposure of Japanese fishermen to radioactive fallout. Anti‐nuclear power movements evolved alongside anti‐nuclear weapons associations as Japan's commercial atomic program moved forward. Japan's unique history created broad sympathy for anti‐nuclear ideologies and victims of the atomic bomb, known as
hibakusha
. This sympathy did not prevent the Japanese government from creating an advanced commercial nuclear program with attempts at a closed fuel cycle and the use of mixed‐oxide (MOX) fuel. Nor did the 11 March 2011 triple disasters – 9.0 magnitude earthquake, 60‐foot tsunami, and fuel meltdowns at the Fukushima Dai‐ichi nuclear plants – put Tokyo off its pro‐nuclear stance. The government continues to promote nuclear power domestically, seeks to restart the many idled reactors, and sells nuclear technology and training to other nations, while standing by its Three Non‐Nuclear Principles (not possessing, manufacturing, or permitting nuclear weapons in Japan).
Anti‐racist Movements (Europe)
Authors: Ruzza Carlo
Published: December 2022

In Europe, anti‐racist protest activities have diffused in recent years and interact with a preceding, durable, and fairly institutionalized cultural current of legally embedded anti‐racist values. Anti‐racism as a value informs several social arenas in which different types of actors contribute to defining and expanding conceptions of citizenship and anti‐racist policies, sometimes using contentious political repertoires. Their efforts also include judicial activism, advocacy at different levels of governance, initiatives in the public sphere, and sensitizing campaigns in social organizations such as workplace organizations, churches, and educational establishments. Anti‐racist activities also emerge in educational institutions and in specific professional contexts, as with the police and probation professionals.
Asylum, Refugee, and Immigration Movements (Australia)
Authors: Tazreiter Claudia
Published: December 2022

Asylum, refugee, and immigration movements in Australia represent distinct, as well as overlapping, repertoires of collective action on behalf of others who are often silent, or silenced in public debates. Various categories of newcomers have differential rights as noncitizens, residents, or “illegals,” and these differences are also reflected in the emergence and vigor of social movements in defense of the “rightless.” These movements have formed, engaged in forms of protest, advocacy, and collective action, and subsided in various waves in reaction to public policy that seeks to restrict the rights of migrants. In Australia such restrictions have been manifested in forms of border control, in limiting access to courts and judicial review processes, through detention, and through deportation. Often the most vulnerable groups of migrants have been the targets of such measures, and it is these groups that movement actors have been engaged in defending.
Consumer Movements
Authors: Forno Francesca
Published: December 2022

The term “consumer movement” indicates a specific area of activism made up of individuals, informal groups, and organizations seeking to empower people both as buyers, enabling them to get the most for their money, and as a political force, striving to rewrite the rules of the marketplace.
French Revolution
Authors: Wernick Andrew
Published: December 2022

In the cascade of uprisings that followed Louis XVI's reluctant convening of the Estates General to address a fiscal and political crisis precipitated by imperial overreach, failing harvests, and the bankruptcy of the French state, the monarchical, feudal, and ecclesiastical pillars of what was immediately dubbed theancien régimewere swept away. By the end of 1789, spurred on by great popular enthusiasm, the Estates General had transmogrified into a unicameral National Assembly, the privileges of the nobility and clergy had been abolished (willingly for some), and an interim body had been set up to draft a new constitution, to be modeled, at first, on that of post‐1688 England. As well, the National Assembly had proclaimed a charter of Rights and Duties of Man and Citizen, including religious freedom, and formally ended feudalism and serfdom. While Paris was the center of these activities the revolution had spread to other urban centers like Lyons and Marseilles, and the rural poor had taken matters in their own hands, refusing taxes, tithes, and seigneurial dues, and looting chateaux and religious houses. The capital itself was awash with section committees, political clubs, agitational newspapers, and, beginning with the July Days and the storming of the Bastille, the increasingly radical actions of the laboring and artisanalsans‐culottes.
Friends of the Earth
Authors: Saunders Clare
Published: December 2022

On its website, Friends of the Earth claims to be “the world's largest grassroots environmental network.” It has chapters in 73 countries, uniting 5000 local groups, and over two million members. Friends of the Earth (FoE) was first established in the US in 1969 by David Brower. Brower was motivated by his disenchantment with the more moderate Sierra Club and the Audubon Society, which he considered were co‐opted by corporate interests and weakened by the “wise use” agenda. Consequently, academic commentators have noted that the foundation of FoE marked the beginning of a “second wave” of environmentalism, more politically oriented and anti‐corporate than the “first wave” conservation organizations that preceded it.
Fréchet Classes
Authors: Durante Fabrizio , Sempi Carlo
Published: December 2022

We describe the notion of Fréchet class as introduced originally by Maurice Fréchet and as it has evolved in present‐day probability and statistics. The main properties of a Fréchet class are described. We also point out how this notion has given rise to that of a copula in order to describe the dependence among the marginals.
System Signatures: A Review
Authors: Asadi Majid , Hashemi Marzieh
Published: December 2022

The signature of coherent systems, as a structure‐dependent concept, is a useful tool for assessing the reliability and stochastic properties of multicomponent systems. In this article, we give various notions of signatures that can be applied to evaluate the reliability of coherent systems when the system components fail under different scenarios. We also briefly review the recent works on applications of signatures in the preventive maintenance of coherent systems.
Digital Infrastructure
Authors: Sinanan Jolynna
Published: December 2022

From an anthropological perspective, it is well recognized that infrastructures have the potential to disrupt and reconfigure communities and environments, lives, and livelihoods. As with other infrastructures, digital infrastructures are often owned and maintained by government entities, as well as by corporations or large companies aligned with political and commercial interests. Anthropological contributions to digital infrastructure not only situate practices within the contextual histories of resources that have shaped them but also allow for fine‐grained attention to the relationship between material and social relations and the stakeholders from global capitalist enterprises to local communities that make up the politics of everyday life. Situating platforms, practices, and environments as main themes, this entry presents an overview of the growing body of work in anthropological approaches to digital infrastructure.
Indigenous Data Sovereignty
Authors: Morphy Frances
Published: December 2022

Indigenous data sovereignty (IDS) describes a global movement that has arisen in response to Indigenous peoples' concerns over the data collected about them by state governments and other agencies, and the uses to which these data are put. Its main proponents are Indigenous people, be they academics, representatives from Indigenous organizations, or members of government agencies. In the spirit of the 2007 UN Declaration on the Rights of Indigenous Peoples, they insist on the right of such peoples to be self‐determining, including having governance of data relevant to addressing their self‐perceived needs and furthering their own aspirations. They reject what they see as the deficit view of encapsulated Indigenous populations that pervades the attitudes and policies of both settler‐state governments and development agencies.
Digital Public Anthropology and the COVID‐19 Pandemic
Authors: Postill John
Published: December 2022

The digital revolution had a paradoxical effect upon public anthropology. On the one hand, it gave public‐minded anthropologists a wealth of tools and platforms with which to reach diverse audiences and create new publics. On the other, it helped to further the ongoing managerialization and quantification of academic labor in the name of efficiency and “public accountability.” In 2020, the COVID‐19 pandemic entered this complex scenario. COVID‐19 transformed the lives of people and organizations worldwide, presenting a host of challenges and opportunities for public anthropologists. This entry explores some of these. It opens with a brief survey of the COVID‐19 public digital anthropology landscape. It then reviews the main themes emerging from the digital responses of public anthropologists to the crisis, namely that lessons from previous medical crises be heeded, the importance of nonmedical knowledge, making inequalities visible, national differences, and the culture wars.
Science, Race, and Racism
Authors: Castro Rosana , Reis‐Castro Luísa
Published: December 2022

How are historically constituted racial technologies and categories mobilized, produced, and materialized in practices and discourses within supposedly universal science? This entry considers the multiple ways in which ethnographic research can showcase how particular histories of racism are updated through scientific practices, and how global scientific projects capitalize on local racial hierarchies. It examines the nexus between science, race, and racism, drawing on ethnographic and historical studies undertaken in Brazil—including the present authors' own research—to highlight how references to miscegenation have been updated and challenged in different situations. The entry emphasizes that anthropological and social studies of science and technology should attend to how issues related to race and racism often emerge in particular, complex, and fraught historical conditions. Such an effort calls for the critical investigation of the ways in which science and technology practices and communities have historically been engendered—and still are—in the processes of racialized hierarchization of certain groups.
Transdisciplinary Multispecies Science in the Anthropocene
Authors: Kaşdoğan Duygu
Published: December 2022

The Anthropocene concept paved the way to diverse debates across the natural sciences, social sciences, humanities, and arts. The range of responses to the Anthropocene at conceptual, theoretical, analytical, and methodological levels has also grown rapidly in the field of anthropology. This entry explores anthropologists' various responses to the Anthropocene with a focus on increasing transdisciplinary collaborations that anthropologists have developed with natural scientists, artists, and activists in conducting multispecies studies. By drawing attention to experimental multispecies studies that break down boundaries among disciplines and between sciences and societies, the entry invites an envisaging oftransdisciplinary multispecies sciencethat decenters human exceptionalism as well as uprooting traditional capitalist, imperialist, colonial, and patriarchal relationships.
Endocarditis among injecting drug users increased markedly: Study
Authors: Knopf Alison
Published: December 2022

The incidence rate of a rare but often fatal inflammation of heart valves in patients with cocaine use disorder or opioid use disorder increased markedly from 2021 to 2022, according to a new study funded by the National Institute on Drug Abuse (NIDA). Physicians have been aware of the increase in infective carditis over the last decade, but recently the condition, which is a significant health concern for people who inject drugs, has been growing. The culprit is not only the injecting, but exacerbation during the COVID‐19 epidemic, according to the study, published last week in Molecular Psychiatry.
Influence of Inclusions in the Corrosion Behavior of Plasma Nitrided Stainless Steel
Authors: Escalada Lisandro , Dalibon Eugenia L. , Brühl Sonia Patricia , Manova Darina , Mändl Stephan , Simison Silvia
Published: December 2022

Plasma nitriding is a well‐established technique to improve hardness and tribological properties of austenitic stainless steel. It is proved that it is also possible to preserve the corrosion resistance after nitriding by controlling the process parameters such as time and temperature, obtaining the so‐called S phase. Herein, the corrosion behavior is evaluated for nitrided layers produced by three different plasma treatments: DC plasma nitriding, plasma immersion ion implantation (PIII), and low‐energy ion implantation (LEII), using different parameters in order to obtain the S‐phase in thickness from 1.2 to about 6 μm without nitride precipitation. The microstructure and chemical composition of the nitrided layers is characterized by means of X‐ray diffraction, secondary‐ion mass spectroscopy, and scanning electron microscopy–focused ion beam. The corrosion behavior is evaluated by means of the cyclic polarization tests in NaCl solution. The morphology of the corrosion attack is studied by optical microscopy and SEM‐FIB, revealing a change from crevice to pitting after the nitriding process. The inclusions are observed to be corrosion initiation sites. Due to this, the thickest nitrided layers (with high N concentration) show better corrosion behavior than the thinner ones.
Fluorinated Solid‐State Electrolytes for Lithium Batteries: Interface Design and Ion Conduction Mechanisms
Authors: Jin Minhuan , Wang Jinyi , Weng Kaiqian , Sun Tianxing , Guo Daying , Wang Xueyu , Chen Xi'an , Wang Shun
Published: December 2022

Fluorinated solid‐state electrolytes (FSSEs) exhibit good compatibility with positive materials, wide electrochemical windows, and stable chemical stability, which have been widely used in all‐solid‐state lithium batteries (ASSLBs). However, the practical application of fluorinated solid electrolytes still faces great challenges due to factors such as ionic conductivity, chemical stability, and current limitation. Herein, the development history of FSSEs is reviewed first. Subsequently, the recent advances in the improvement of ion conductivity, chemical stability, and current limit by structural design, interface regulation strategies, etc. are analyzed. Finally, the design requirements for future generations of FSSEs are prospected, focusing on the latest simple one‐step synthesis methods, improving the ionic conductivity at room temperature, and optimizing the electrochemical stability window of FSSEs.
All‐Visible‐Light Triggered Photoswitch of Dithienylethene Derivatives with Molecular Conformation Changes Excess 5 Å
Authors: Luo Miao , Zhao Juan , Liu Yanyan , Mao Zhu , Wang Sheng , Chi Zhenguo
Published: December 2022

Developing new all‐visible‐light driven fluorescent molecular switches has attracted much interests due to their important application prospects in materials science and life science. Herein, three novel all‐visible‐light triggered fluorescent molecular photoswitches (2P3, 4F, and 4Cl) are designed and prepared, which are realized by prolonging π‐conjugation length with aggregated‐induced emission units. These photoswitches show reversible photochromic and fluorescent switching in dilute solutions and films under 420 nm and 560 nm irradiations. Meanwhile, upon alternating irradiations with 450 nm/560 nm light, effective photochromic and fluorescent switching in powder states are also achieved. More interestingly, two distinct conformations with different photochromic abilities can be altered by solvents polarity. The size difference of the two conformations is over 5 Å in the vertical direction which is one of the largest changes among photochromic molecules based on dithienylethene. The accompanying conformational changes are analysed to understand the relationship between solvent characteristics and crystal structure, as well as the intermolecular interaction in solid state for all‐visible‐light triggered photoswitching molecules.
Nanoparticle‐Mediated Radiotherapy Remodels the Tumor Microenvironment to Enhance Antitumor Efficacy
Authors: Zhen Wenyao , Weichselbaum Ralph R. , Lin Wenbin
Published: December 2022

Radiotherapy (RT) uses ionizing radiation to eradicate localized tumors and, in rare cases, control tumors outside of the irradiated fields via stimulating an antitumor immune response (abscopal effect). However, the therapeutic effect of RT is often limited by inherent physiological barriers of the tumor microenvironment (TME), such as hypoxia, abnormal vasculature, dense extracellular matrix (ECM), and an immunosuppressive TME. Thus, it is critical to develop new RT strategies that can remodel the TME to overcome radio‐resistance and immune suppression. In the past decade, high‐Z‐element nanoparticles have been developed to increase radiotherapeutic indices of localized tumors by reducing X‐ray doses and side effects to normal tissues and enhance abscopal effects by activating the TME to elicit systemic antitumor immunity. In this review, the principles of RT and radiosensitization, the mechanisms of radio‐resistance and immune suppression, and the use of various nanoparticles to sensitize RT and remodel TMEs for enhanced antitumor efficacy are discussed. The challenges in clinical translation of multifunctional TME‐remodeling nanoradiosensitizers are also highlighted.
Holographically Activatable Nanoprobe via Glutathione/Albumin‐Mediated Exponential Signal Amplification for High‐Contrast Tumor Imaging
Authors: Li Ting , Tan Shuangxiu , Li Mengjuan , Luo Jie , Zhang Yueyue , Jiang Zhen , Deng Yibin , Han Liang , Ke Hengte , Shen Junkang , Tang Yong'an , Liu Fan , Chen Huabing , Yang Tao
Published: December 2022

Glutathione (GSH)‐activatable probes hold great promise for in vivo cancer imaging, but are restricted by their dependence on non‐selective intracellular GSH enrichment and uncontrollable background noise. Here, a holographically activatable nanoprobe caging manganese tetraoxide is shown for tumor‐selective contrast enhancement in magnetic resonance imaging (MRI) through cooperative GSH/albumin‐mediated cascade signal amplification in tumors and rapid elimination in normal tissues. Once targeting tumors, the endocytosed nanoprobe effectively senses the lysosomal microenvironment to undergo instantaneous decomposition into Mn2+ with threshold GSH concentration of ≈ 0.12 mm for brightening MRI signals, thus achieving high contrast tumor imaging and flexible monitoring of GSH‐relevant cisplatin resistance during chemotherapy. Upon efficient up‐regulation of extracellular GSH in tumor via exogenous injection, the relaxivity‐silent interstitial nanoprobe remarkably evolves into Mn2+ that are further captured/retained and re‐activated into ultrahigh‐relaxivity‐capable complex by stromal albumin in the tumor, and simultaneously allows the renal clearance of off‐targeted nanoprobe in the form of Mn2+ via lymphatic vessels for suppressing background noise to distinguish tiny liver metastasis. These findings demonstrate the concept of holographic tumor activation via both tumor GSH/albumin‐mediated cascade signal amplification and simultaneous background suppression for precise tumor malignancy detection, surveillance, and surgical guidance.
Light‐Fueled Nonreciprocal Self‐Oscillators for Fluidic Transportation and Coupling
Authors: Deng Zixuan , Zhang Hang , Priimagi Arri , Zeng Hao
Published: December 2022

Light‐fueled self‐oscillators based on soft actuating materials have triggered novel designs for small‐scale robotic constructs that self‐sustain their motion at non‐equilibrium states and possess bioinspired autonomy and adaptive functions. However, the motions of most self‐oscillators are reciprocal, which hinders their use in sophisticated biomimetic functions such as fluidic transportation. Here, an optically powered soft material strip that can perform nonreciprocal, cilia‐like, self‐sustained oscillation under water is reported. The actuator is made of planar‐aligned liquid crystal elastomer responding to visible light. Two laser beams from orthogonal directions allow for piecewise control over the strip deformation, enabling two self‐shadowing effects coupled in one single material to yield nonreciprocal strokes. The nonreciprocity, stroke pattern and handedness are connected to the fluidic pumping efficiency, which can be controlled by the excitation conditions. Autonomous microfluidic pumping in clockwise and anticlockwise directions, translocation of a micro‐object by liquid propulsion, and coupling between two oscillating strips through liquid medium interaction are demonstrated. The results offer new concepts for non‐equilibrium soft actuators that can perform bio‐like functions under water.