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In this work, the Common Model of Multi-phase Strength and Equation of State (CMMP) model was applied to tin. Specifically, calibrations of the strength-specific elements of the CMMP foundation were developed with a combination of experiments and theory, and then the model was validated experimentally. The first element of the foundation is a multi-phase analytic treatment of the melt temperature and the shear modulus for the solid phases. These models were parameterized for each phase based on ab initio calculations using the software VASP (Vienna Ab initio Simulations Package) based on density functional theory. The shear modulus model for the ambient β phase was validated with ultrasonic sound speed measurements as a function of pressure and temperature. The second element of the foundation is a viscoplastic strength model for the β phase, upon which strength for inaccessible higher-pressure phases can be scaled as necessary. The stress–strain response of tin was measured at strain rates of 10 − 3 to 3 × 10 3 s − 1 and temperatures ranging from 87 to 373 K. The Preston–Tonks–Wallace (PTW) strength model was fit to that data using Bayesian model calibration. For validation, six forward and two reverse Taylor impact experiments were performed at different velocities to measure large plastic deformation of tin at strain rates up to 10 5 s − 1 . The PTW model accurately predicted the deformed shapes of the cylinders, with modest discrepancies attributed to the inability of PTW to capture the effects of twinning and dynamic recrystallization. Some material in the simulations of higher velocity Taylor cylinders reached the melting temperature, thus testing the multiphase model because of the presence of a second phase, the liquid. In simulations using a traditional modeling approach, the abrupt reduction of strength upon melt resulted in poor predictions of the deformed shape and non-physical temperatures. With CMMP, the most deformed material points evolved gradually to a mixed solid–liquid but never a fully liquid state, never fully lost strength, stayed at the melt temperature as the latent heat of fusion was absorbed, and predicted the deformed shape well. [ABSTRACT FROM AUTHOR]

Soil health is not explicitly included in current stream and floodplain restorations. This may be one of the many reasons that stream restorations are not achieving their full restoration and ecological benefits. The lack of design and implementation procedures for providing healthy soils and the absence of specific soil metrics for evaluation are some of the reasons for the non-inclusion of soil health in floodplain restorations. Here, we have brought together a team of researchers and practitioners to provide a blueprint for the inclusion of soil health in floodplain restorations, with a specific emphasis on approaches that may be easily accessible for practitioners. We describe the challenges posed by current restoration procedures for physical, chemical, and biological soil conditions. The top ten soil metrics that could be easily measured and could be leveraged by practitioners to assess floodplain soil conditions before and after restorations were identified and selected. The best design and construction practices for improving soil health on floodplains are presented. We also recommend that the current crediting approaches and regulatory mechanisms for stream restorations be updated to incentivize soil health. The inclusion of soil health will help us attain the ecological services and functional uplift goals that are being targeted by environmental agencies and the restoration community. [ABSTRACT FROM AUTHOR]

Control of oxygen fugacity during high-temperature phase equilibrium experiments is required to simulate the conditions that exist in natural systems. At high pressures, oxygen fugacity may be imposed using solid buffer equilibria via the classic "double capsule" technique. This design becomes untenable, however, at temperatures above the melting points of commonly used noble metal capsule materials and/or where buffer assemblages may alloy with the capsule or contaminate the sample. Here we introduce and test a modified double capsule approach that includes a solid metal-oxide buffer in close proximity to but separate from the sample of interest. Buffers used include (in order of most oxidized to reduced) Ni-NiO, Co-CoO, W-WO3, Fe-FeO, Mo-MoO2, Cr-Cr2O3, V-V2O3, Ta-Ta2O5, and Nb-NbO. At a fixed temperature, these buffers span a wide range—up to 10 log fO2 units. To demonstrate the buffering capacity of this double capsule approach, secondary redox equilibria and V-doped CaO-MgO-Al2O3-SiO2 system glasses were studied in experiments using the double capsule geometry. The secondary equilibria provide an independent verification of the oxygen fugacity established in the double capsule environment. The glasses proved difficult to interpret, and our results provide guidance to future efforts to utilize the glass oxybarometer at reducing conditions. Application of this modified double capsule technique to studies of V valence in MgAl2O4 spinels led to the recognition of several factors that will affect V valence in this system: temperature of equilibration, duration of experiment, and spinel bulk composition. We have synthesized V-bearing MgAl2O4 spinel at the reduced conditions of the Cr-Cr2O3, (IW-3.51), Ta-Ta2O5, (IW-5.37), and Nb-NbO buffers (IW-5.44). This spinel exhibits a very small V3+ pre-edge peak consistent with its reduced nature. The absence of evidence for V2+ suggests that MgAl2O4 spinel excludes V2+ due to the preference of V for octahedral sites. This finding is supported by DFT calculations for spinels of variable composition, and in agreement with some other indirect evidence for preference for V3+ in aluminous spinels (Bosi et al. 2016,; Paque et al. 2013,). [ABSTRACT FROM AUTHOR]

Jackson, rather unconvincingly, attributes the central scenes of I Arden i to Shakespeare, but Freebury-Jones disputes this claim and attributes the entire play to Kyd. I Shakespeare's Tutor i does not, however, simply remove texts from the Shakespeare canon: this chapter concludes by ascribing the "additions" to the fourth quarto of I The Spanish Tragedy i (1602) to Shakespeare. I Shakespeare's Tutor i is a book with two principal objectives. [Extracted from the article]

QUEEN Elizabeth takes her seat in the theater, and around her are gathered the glittering ranks of her most important courtiers, senior figures from the aristocracy, and a select band [...]

An American population geographer and specialist on demographic trends in the former Soviet republics examines the results of the first post-Soviet census of Moldova (the poorest country of Europe), conducted in 2004 and released years later. He reviews major national- and regional-level changes in population size, urban/rural distribution, and ethnicity since the last Soviet-era census in 1989 and reconciles the two sets of data. A major factor complicating the analysis is the de facto secession in 1992 of an eastern region of the country, now known as the Pridnestrovskaya Moldavskaya Republic (PMR), which prompted a brief war and subsequent uneasy ceasefire later that year. However, a population enumeration conducted in the PMR, also in 2004 (and released later), facilitates the identification of overall demographic trends in the region, which may experience the involuntary return of jobless migrant workers from Russia and the EU due to the 2008/2009 global recession. Classification Numbers: J110, O180, R230.2 figures, 2 tables, 49 references. Key words: Moldova, Transnistria, Chisinau, emigration, urbanization, demographic trends.

A U.S. population geographer specializing in the former Soviet Union surveys the results of an October 2005 census conducted in a contested pseudo-state known as the Nagorno-Karabakh Republic (NKR). Data from the enumeration provide the first credible information about recent population characteristics, including nationality composition and migration from the war-torn republic. The data make it possible to ascertain the crude magnitudes of population losses in the republic's constituent rayons as well as changes resulting from deaths and expulsion of ethnic Armenians and/or Azerbaijanis. Changes documented since the last (1989) Soviet census in the region indicate that the current republic's population differs quite dramatically from that of the former Nagomo-Karabakh Autonomous Oblast of Azerbaijan, complicating efforts to broker a lasting peace agreement between the pseudo-state's two neighbors. Journal of Economic Literature, Classification Numbers: J11, O18, R23. 1 figure, 1 table, 36 references. Key words: Nagomo-Karabakh, Armenia, Azerbaijan, Stepanakert, population census, migration, abandoned settlements, ethnic tension.

An American geographer and specialist on population change in the former Soviet republics presents a study of the first post-Soviet census of Armenia. The author reviews major national- and regional-level changes in population size, urban/rural distribution, and ethnic affinity, by focusing on disruptive effects of the 1988 earthquake on the last Soviet census enumeration (1989), which hinders temporal comparisons. Also included in his study is the largely economically based mass migration to other former Soviet republics (chiefly to Russia) and the United States; an internal territorial reorganization in 1995; and migration streams of Armenian displaced persons and refugees as well as emigration of Azeris as a consequence of the Nagorno-Karabakh conflict noted in some detail. Journal of Economic Literature, Classification Numbers: J11, O18, R23.3 figures, 2 tables, 60 references. Key words: Armenia, population change, emigration, urbanization, demographic trends, Nagorno-Karabakh, Spitak earthquake, Azerbaijan, Armenian-Azeri conflict, Yerevan.

An American geographer and specialist on urbanization and population change in the countries of the former USSR summarizes major results of the first post-Soviet census of Georgia, only recently released. After describing sources of census data and methodological issues warranting attention (e.g., exclusion of most of Abkhazia and South Ossetia and movements of internally displaced persons), he reviews significant national-and regional-level developments in population size, urban and rural distribution, and ethnic affiliation in the country. Classification Numbers: J11, O18,R23.3 figures, 3 tables, 34 references. Key words: population change, Georgia, urbanization, internally displaced persons, demographic trends, Abkhazia, South Ossetia.

An American geographer and noted specialist on urbanization and population dynamics in the countries of the former Soviet Union reviews the major results of the first post-Soviet census in Tajikistan, conducted in 2000 and only recently released to the public. The author examines salient influences on population change, at both the national and regional level, over the period since the last Soviet census (1989). Presented and discussed in the paper are internal population redistribution resulting from the Tajik civil war (1992-1997), continuing high rates of natural increase among ethnic Tajiks, substantial emigration of non-titular populations (especially Russians and Uzbeks), shifts in the country's ethnic balance, and de-urbanization. Journal of Economic Literature, Classification Numbers: J11, O18, R23. 3 figures, 4 tables, 29 references. Key words: population change, Tajikistan, urbanization, emigration, demographic trends.

American specialist on urbanization and population dynamics in the countries of the former Soviet Union examines changes in Ukraine's population revealed by analysis of that country's first post-Soviet census (2001). Among the more salient developments examined in this second-largest post-Soviet republic are extremely high rates of natural population decrease among Ukrainians and Russians alike, a substantial exodus of ethnic Russians from Ukraine (and in some cases their ethnic re-identification as Ukrainians) with major implications for nationality distribution both at the national and regional levels, and interesting trends involving other minority nationalities such as (Crimean) Tatars, Armenians, and Jews.

An American specialist on urbanization and population dynamics in the countries of the former Soviet Union examines changes in Azerbaijan's population revealed by analysis of that country's first post-Soviet (1999) census and official 2002 population estimates. Particular attention is devoted to the ongoing conflict between Azerbaijan and Armenia over the contested territory of Nagorno-Karabakh, in terms of its effects on total population size (mortality and refugee flows into and out of the country) and the internal distribution of population within the country (involuntary migration of internally displaced persons). Journal of Economic Literature, Classification Numbers: J11, O18, R23. 2 figures, 4 tables, 44 references.

The author, a U.S. geographer specializing in issues of population change and urbanization in the countries of the former USSR, extends an earlier study of the population of Belarus (Rowland, 2003) by focusing on trends of change in the nationality composition of that country's population revealed by the most recent (1999) census. More specifically, the paper analyzes trends and patterns of the nationality composition of the total, urban, and rural Belarusian population at both the national and regional levels for the period 1989-1999. Journal of Economic Literature, Classification Numbers: J11, O18, R23.3 figures, 10 tables, 10 references.

An American geographer studying population change and urbanization in the former USSR focuses on trends revealed by comparison of the two most recent censuses conducted in Belarus. National and regional total, urban, and rural population change is analyzed for the period 1989-1999, with selected updating to 2001 and 2002. Patterns of fertility, mortality, natural increase, and migration also are addressed where relevant to an understanding of general population trends. Particular effort is devoted to detecting population movements resulting from the Chernobyl' nuclear accident in nearby northern Ukraine in 1986. Journal of Economic Literature, Classification Numbers: J11, O18, R23.2 figures, 3 tables, 35 references, 2 appendices.

A specialist on population change and urbanization in the countries of the former USSR examines nationwide and regional total, urban, and rural population change in Kyrgyzstan for 1989-1999--the period between the last census of the former USSR and the first census of independent Kyrgyzstan--with selected updates to 2001. Of particular interest is the availability of oblast-level nationality data making possible the detailed investigation of changes in the regional and rural-urban populations of major nationality groups in Kyrgyzstan. A focus is on the decreasing sizes of Russian, Ukrainian, and German populations and population growth among ethnic Kyrgyz and Uzbeks. Journal of Economic Literature, Classification Numbers: O18, R12, R23.4 figures, 17 tables, 41 references.

An American geographer specializing in population change and urbanization in the countries of the former USSR examines nationwide and regional total, urban, and rural population change in Kazakhstan for 1989-1999, using data from the recently released 1999 census of Kazakhstan. Of particular interest is the analysis of nationality data in the census, available at a level of detail not matched since the last Soviet census in 1989. For the first time in more than a decade, a detailed investigation is possible of changes in the regional and rural-urban populations of major nationality groups in Kazakhstan during the 1990s. Journal of Economic Literature, Classification Numbers: O18, R12, R23. 10 figures, 15 tables, 35 references.

An American geographer specializing in population change and urbanization in countries of the former USSR analyzes spatial patterns of urban population change in Ukraine from 1989 to 1999, utilizing data from the 1989 USSR census and official 1999 population estimates. General urban population dynamics first are investigated at the national and oblast levels, with a focus on the effects of natural population dynamics and migration. The analysis then shifts to individual urban centers, focusing on rapidly growing, declining, and disappearing and new towns. Linkages are explored between towns of each type and their major economic functions.

An American geographer specializing in population change and urbanization in the countries of the former USSR examines urban population change in Kazakhstan over the period 1989-1998. The focus is on trends in urbanization, urban population growth, and changes in the populations of individual urban centers, with discussion of the latter emphasizing locational patterns and economic functions of the centers. The analysis is based on materials from the 1989 USSR census, official 1995-1998 population estimates, and preliminary results from the 1999 Kazakhstan census, with extensive coverage devoted to the availability of information in a variety of Kazakh statistical sources and other publications.

An assessment of the population trends within the metropolitan areas in Russia and the Former Soviet Union from 1897 to 1997, with emphasis on the period between 1970 and 1997, is presented. The metropolitan areas considered are those having more than one million people with a central city and other urban centers of more than 15,000 people within a 50-mi radius. It was observed that the rapid population growth from 1970 to 1989 slowed down during the 1980s and 1990s. Moreover, the population shift form the central city to suburbs was very slight.