The break-up of the Ottoman empire and the disintegration of the Russian empire were watershed events in modern history. The unravelling of these empires was both cause and consequence of World War I ...and resulted in the deaths of millions. It irrevocably changed the landscape of the Middle East and Eurasia and reverberates to this day in conflicts throughout the Caucasus and Middle East. Shattering Empires draws on extensive research in the Ottoman and Russian archives to tell the story of the rivalry and collapse of two great empires. Overturning accounts that portray their clash as one of conflicting nationalisms, this pioneering study argues that geopolitical competition and the emergence of a new global interstate order provide the key to understanding the course of history in the Ottoman-Russian borderlands in the twentieth century. It will appeal to those interested in Middle Eastern, Russian, and Eurasian history, international relations, ethnic conflict, and World War I.
Improving production of shale gas and tight oil from low-permeability formations has dominated the energy landscape over the past two decades. Successful applications of horizontal drilling combined ...with hydraulic fracturing (HF) techniques, first demonstrated in the Texas Barnett shales in the 1990s, are the impetus for the current shale boom in the Americas. Chemicals are at the heart of the fracturing (or “fracking”) process, which includes pumping a water-based fluid and proppant into a shale formation to create fissures that access the buried hydrocarbons. The fracturing fluid composition is critical to the completion design and should reduce wellbore friction while enabling proppant placement into the fractures. However, adding too many chemicals without properly evaluating the fracturing fluid formulation can lead to increased cost, poor fluid performance, or even damage to the reservoir. This review discusses the purpose of each chemical used in HF fluids, the techniques applied by the production chemist to assess fluid performance, and suggested best practices in optimizing formulations to reduce costs, enhance performance, and improve footprint.
Transition-metal sulfides are prodigiously studied materials with a 100-year history in the development of catalysts and hierarchal structures found throughout the energy industry. A constructive ...subset of these compounds are the Group VI tetrathiometallates of the form MS42–(where M = Mo or W) that are used as building blocks in a variety of complex chalcogenide-based materials. Originally used as structural motifs for building nitrogenase model clusters, these salts have since been incorporated into commercially relevant products, such as pharmaceuticals, unsupported catalysts, porous networks for separations, and solar cell components. Tetrathiometallate anions are advantageous as metal sulfide constructs, because of their simple synthesis and solubility in aqueous or polar hydrocarbon solvents made tunable by selection of the proper cation. This minireview will provide historical context of MS42– salts used in the preparation of conventional sulfide materials and discuss their relevance to areas related to the energy transition. Examples of the latter include their use as catalysts for crude oil conversion, as porous structures for gas separations or contaminant removal, and in electrodes for photoelectrochemical devices.
Previous research on both hedonic and utilitarian shopping value has focused much effort on the antecedents of shopping value with very little emphasis on the outcomes of shopping value. This study ...investigates the complex interrelationships between satisfaction with the retailer, hedonic and utilitarian shopping value, and important retail outcomes. Both hedonic and utilitarian shopping values are found to influence key retail outcomes. The results also support predicted differences in the relative influence of hedonic and utilitarian shopping value. Hedonic and utilitarian shopping values are also found to moderate a number of relationships between satisfaction and retail outcomes.
Background and Aims
The scope of this working group was to review (1) ecological interactions at the dental biofilm in health and disease, (2) the role of microbial communities in the pathogenesis of ...periodontitis and caries, and (3) the innate host response in caries and periodontal diseases.
Results and Conclusions
A health‐associated biofilm includes genera such as Neisseria, Streptococcus, Actinomyces, Veillonella and Granulicatella. Microorganisms associated with both caries and periodontal diseases are metabolically highly specialized and organized as multispecies microbial biofilms. Progression of these diseases involves multiple microbial interactions driven by different stressors. In caries, the exposure of dental biofilms to dietary sugars and their fermentation to organic acids results in increasing proportions of acidogenic and aciduric species. In gingivitis, plaque accumulation at the gingival margin leads to inflammation and increasing proportions of proteolytic and often obligately anaerobic species. The natural mucosal barriers and saliva are the main innate defence mechanisms against soft tissue bacterial invasion. Similarly, enamel and dentin are important hard tissue barriers to the caries process. Given that the present state of knowledge suggests that the aetiologies of caries and periodontal diseases are mutually independent, the elements of innate immunity that appear to contribute to resistance to both are somewhat coincidental.
Biologic therapies can be highly effective for the treatment of severe psoriasis, but response for individual patients can vary according to drug. Predictive biomarkers to guide treatment selection ...could improve patient outcomes and treatment cost-effectiveness.
We sought to test whether HLA-C*06:02, the primary genetic susceptibility allele for psoriasis, predisposes patients to respond differently to the 2 most commonly prescribed biologics for psoriasis: adalimumab (anti–TNF-α) and ustekinumab (anti–IL-12/23).
This study uses a national psoriasis registry that includes longitudinal treatment and response observations and detailed clinical data. HLA alleles were imputed from genome-wide genotype data for 1326 patients for whom 90% reduction in Psoriasis Area and Severity Index score (PASI90) response status was observed after 3, 6, or 12 months of treatment. We developed regression models of PASI90 response, examining the interaction between HLA-C*06:02 and drug type (adalimumab or ustekinumab) while accounting for potentially confounding clinical variables.
HLA-C*06:02–negative patients were significantly more likely to respond to adalimumab than ustekinumab at all time points (most strongly at 6 months: odds ratio OR, 2.95; P = 5.85 × 10−7), and the difference was greater in HLA-C*06:02–negative patients with psoriatic arthritis (OR, 5.98; P = 6.89 × 10−5). Biologic-naive patients who were HLA-C*06:02 positive and psoriatic arthritis negative demonstrated significantly poorer response to adalimumab at 12 months (OR, 0.31; P = 3.42 × 10−4). Results from HLA-wide analyses were consistent with HLA-C*06:02 itself being the primary effect allele. We found no evidence for genetic interaction between HLA-C*06:02 and ERAP1.
This large observational study suggests that reference to HLA-C*06:02 status could offer substantial clinical benefit when selecting treatments for severe psoriasis.
p120-catenin stabilizes epithelial cadherin (E-cadherin) in SW48 cells, but the mechanism has not been established. Here, we show that p120 acts at the cell surface to control cadherin turnover, ...thereby regulating cadherin levels. p120 knockdown by siRNA expression resulted in dose-dependent elimination of epithelial, placental, neuronal, and vascular endothelial cadherins, and complete loss of cell-cell adhesion. ARVCF and δ-catenin were functionally redundant, suggesting that proper cadherin-dependent adhesion requires the presence of at least one p120 family member. The data reveal a core function of p120 in cadherin complexes, and strongly predict a dose-dependent loss of E-cadherin in tumors that partially or completely down-regulate p120.
Hydraulic fracturing (HF), or “fracking,” is the driving force behind the “shale gas revolution,” completely transforming the United States energy industry over the last two decades. HF requires that ...4–6 million gallons per well (15,000–23,000 m3/well) of water be pumped underground to stimulate the release of entrapped hydrocarbons from unconventional (i.e., shale or carbonate) formations. Estimated U.S. produced water volumes exceed 150 billion gallons/year across the industry from unconventional wells alone and are projected to grow for at least another two decades. Concerns over the environmental impact from accidental or incidental release of produced water from HF wells (“U-PW”), along with evolving regulatory and economic drivers, has spurred great interest in technological innovation to enhance U-PW recycling and reuse. In this review, we analyze U-PW quantity and composition based on the latest U.S. Geographical Survey data, identify key contamination metrics useful in tracking water quality improvement in the context of HF operations, and suggest “fit-for-purpose treatment” to enhance cost-effective regulatory compliance, water recovery/reuse, and resource valorization. Drawing on industrial practice and technoeconomic constraints, we further assess the challenges associated with U-PW treatment for onshore U.S. operations. Presented are opportunities for targeted end-uses of treated U-PW. We highlight emerging technologies that may enhance cost-effective U-PW management as HF activities grow and evolve in the coming decades.
•PW reuse can minimize water withdrawals and disposal injection activities.•Temporal and geographic variation in PW quality necessitates treatment versatility.•High matrix variability and remote operations present unique treatment challenges.•Current treatment options lack contaminant specificity, and emphasize desalination.•“Fit-for-purpose” treatments can greatly enhance treatment capacity and lower costs.
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•Unsupported and supported Ni(H2PO2)2 reacts to form Ni2P at 468–561K.•Ni(H2PO2)2 precursors can be reduced in situ to give highly-active Ni2P catalysts.•Ni2P/SiO2 and Ni2P/Al2O3 had ...higher turnover frequencies than Ni–Mo/Al2O3.•The surfaces of hypophosphite-derived Ni2P catalysts are highly enriched in P.
An in situ method for the preparation of nickel phosphide (Ni2P) on silica, alumina, and amorphous silica-alumina (ASA) supports is described. The synthesis avoids the use of nickel and phosphorus salts by employing the reaction between nickel hydroxide (Ni(OH)2) and hypophosphorus acid (H3PO2), allowing the impregnation of nickel hypophosphite (Ni(H2PO2)2) onto the oxide supports in the absence of salt by-products. Temperature-programmed reduction (TPR) in flowing hydrogen at 573–773K yields phase pure Ni2P on the supports with small average particle sizes (3–4nm) as measured using transmission electron microscopy. The conversion of Ni(H2PO2)2 to Ni2P and related reactions were probed using TPR with on-line mass spectral analysis of the gas effluent. Unsupported Ni(H2PO2)2 reacts in flowing hydrogen to produce PH3 and H2O at 468 and 482K, respectively; the reaction is shifted to increasingly higher temperatures for Ni(H2PO2)2 supported on SiO2, Al2O3 and ASA. The hydrodenitrogenation (HDN) and hydrodesulfurization (HDS) properties of the Ni2P catalysts were probed using a mixed feed containing carbazole and benzothiophene. While Ni2P/SiO2 catalysts prepared by the different methods exhibited similar HDN and HDS activities, the in situ prepared Ni2P/Al2O3 and Ni2P/ASA catalysts were substantially more active than their ex situ counterparts prepared from hypophosphite- and phosphate-based precursors.
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