Existing work seeks explanations for state repression mainly in domestic factors such as ethnic/religious cleavages, poverty and inequality, struggle for power, regime type and quality of state ...institutions, lack of loyalty, demand for scapegoats, and cultural or psychological traits of perpetrators. How foreign influences shape state repression has been given less attention. Furthermore, the focus of the empirical literature has been largely cross-country, leaving much local variation unexplained. In this article, I examine how far foreign interests can explain the local (spatial) variation of deportations and massacres during the Armenian genocide. Between 1915 and 1917 the Ottoman Empire carried out a massive campaign of state repression (deportations and massacres) against its Armenian population. There was meaningful variation across Ottoman provinces in the intensity of this campaign, that is, some provinces experienced more repression than others. I investigate the determinants of this spatial variation. My empirical analysis is guided by a rationalist (economic) model where deportation is a tool to stifle Armenian calls for independence, but the benefit and cost of deportation vary spatially. For example, deportation is costlier (i.e. the risk of foreign intervention is greater) in locations where foreign economic and military interests are threatened by the departure of Armenians. In line with the model’s predictions, my empirical analysis indicates that there were fewer deportations in places where Armenians worked for the German-owned railway.
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NUK, OILJ, SAZU, UKNU, UL, UM, UPUK
The profound changes in global SOsubscript 2 emissions over the last decades have affected atmospheric composition on a regional and global scale with large impact on air quality, atmospheric ...deposition and the radiative forcing of sulfate aerosols. Reproduction of historical atmospheric pollution levels based on global aerosol models and emission changes is crucial to prove that such models are able to predict future scenarios. Here, we analyze consistency of trends in observations of sulfur components in air and precipitation from major regional networks and estimates from six different global aerosol models from 1990 until 2015. There are large interregional differences in the sulfur trends consistently captured by the models and observations, especially for North America and europe. europe had the largest reductions in sulfur emissions in the first part of the period while the highest reduction came later in North America and east Asia. the uncertainties in both the emissions and the representativity of the observations are larger in Asia. However, emissions from East Asia clearly increased from 2000 to 2005 followed by a decrease, while in India a steady increase over the whole period has been observed and modelled. the agreement between a bottom-up approach, which uses emissions and process-based chemical transport models, with independent observations gives an improved confidence in the understanding of the atmospheric sulfur budget.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
The standard core accretion model for planetesimal formation in protoplanetary discs (PPDs) is subject to a number of challenges. One is related to the vertical settling of dust to the disc mid-plane ...against turbulent stirring. This is particularly relevant in the presence of the vertical shear instability (VSI), a purely hydrodynamic instability applicable to the outer parts of PPDs, which drives moderate turbulence characterized by large-scale vertical motions. We investigate the evolution of dust and gas in the vicinity of local pressure enhancements (pressure bumps) in a PPD with turbulence sustained by the VSI. Our goal is to determine the morphology of dust concentrations and if dust can concentrate sufficiently to reach conditions that can trigger the streaming instability (SI). We performed a suite of global 2D axisymmetric and 3D simulations of dust and gas for a range of values for Σ
d
∕Σ
g
(ratio of dust-to-gas surface mass densities or metallicity), particle Stokes numbers,
τ
, and pressure bump amplitude,
A
. Dust feedback onto the gas is included. For the first time, we use global 3D simulations to demonstrate the collection of dust in long-lived vortices induced by the VSI. These vortices, which undergo a slow radial inward drift, are the dusty analogs of large long-lived vortices found in previous dust-free simulations of the VSI. Without a pressure bump and for solar metallicity
Z
≈ 0.01 and Stokes numbers
τ
~ 10
−2
, we find that such vortices can reach dust-to-gas density ratios slightly below unity in the discs’ mid-plane, while for
Z
≳ 0.05, long-lived vortices are largely absent. In the presence of a pressure bump, for
Z
≈ 0.01 and
τ
~ 10
−2
, a dusty vortex forms that reaches dust-to-gas ratios of a few times unity, such that the SI is expected to develop, before it eventually shears out into a turbulent dust ring. At intermediate metallicities,
Z
~ 0.03, this occurs for
τ
~ 5 × 10
−3
, but with a weaker and more short-lived vortex, while for larger
τ
, only a turbulent dust ring forms. For
Z
≳ 0.03, we find that the dust ring becomes increasingly axisymmetric for increasing
τ
and dust-to-gas ratios reach order unity for
τ
≳ 5 × 10
−3
. Furthermore, the vertical mass flow profile of the disc is strongly affected by dust for
Z
≳ 0.03, such that gas is transported inward near the mid-plane and outward at larger heights, which is the reversed situation compared to simulations with zero or small amounts of dust. We find viscous
α
-values to drop moderately as ~10
−3
–10
−4
for metallicities increasing as
Z
= 0–0.05. Our results suggest that the VSI can play an active role in the formation of planetesimals through the formation of vortices for plausible values of metallicity and particle size. Also, it may provide a natural explanation for the presence or absence of asymmetries of observed dust rings in PPDs, depending on the background metallicity.
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Anti-refugee violence often accompanies refugee migration, but the factors that fuel or mitigate that violence remain poorly understood, including the common policy response in such settings of ...humanitarian aid. Existing theory and policy debates predict that aid to refugees exacerbates anti-refugee violence by increasing hosts’ resentment toward refugees. In contrast, however, aid may reduce violence in ways such as increasing host communities’ well-being through more demand for local goods and services and refugees sharing aid. We test for the sign and mechanisms of this relationship. Evidence from original survey data and a regression discontinuity design suggests that cash transfers to Syrian refugees in Lebanon did not increase anti-refugee violence, and if anything they reduced violence. Exploring why aid does not increase hostility, we find evidence that aid allows recipients to indirectly compensate locals through higher demand for local goods and services, directly benefit locals by offering help and sharing aid, and reduce contact with potential aggressors.
Rapid development of agriculture and fossil fuel combustion greatly increased US reactive nitrogen emissions to the atmosphere in the second half of the 20th century, resulting in excess nitrogen ...deposition to natural ecosystems. Recent efforts to lower nitrogen oxides emissions have substantially decreased nitrate wet deposition. Levels of wet ammonium deposition, by contrast, have increased in many regions. Together these changes have altered the balance between oxidized and reduced nitrogen deposition. Across most of the United States, wet deposition has transitioned from being nitrate-dominated in the 1980s to ammonium-dominated in recent years. Ammonia has historically not been routinely measured because there are no specific regulatory requirements for its measurement. Recent expansion in ammonia observations, however, along with ongoing measurements of nitric acid and fine particle ammonium and nitrate, permit new insight into the balance of oxidized and reduced nitrogen in the total (wet + dry) US nitrogen deposition budget. Observations from 37 sites reveal that reduced nitrogen contributes, on average, ∼65% of the total inorganic nitrogen deposition budget. Dry deposition of ammonia plays an especially key role in nitrogen deposition, contributing from 19% to 65% in different regions. Future progress toward reducing US nitrogen deposition will be increasingly difficult without a reduction in ammonia emissions.
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BFBNIB, NMLJ, NUK, PNG, SAZU, UL, UM, UPUK
Pollination services provided by solitary bees, the largest group of bees worldwide, are critical to the vitality of ecosystems and agricultural systems alike. Disconcertingly, bee populations are in ...decline, and while no single causative factor has been identified, pesticides are believed to play a role in downward population trends. The effects of pesticides on solitary bee species have not been previously systematically cataloged and reviewed.
This systematic scoping review examines available evidence for effects of pesticide exposure on solitary bees to identify data gaps and priority research needs.
A systematic literature search strategy was developed to identify and document reports on solitary bee pesticide exposure-effects investigations. Literature was subsequently screened for relevance using a Population, Exposures, Comparators, and Outcomes (PECO) statement and organized into a systematic evidence map. Investigations were organized by effect category (lethal effects on immatures, lethal effects on adults, sublethal effects on immatures, and sublethal effects on adults), species, pesticide class, and publication year.
A comprehensive literature search of Web of Science and ProQuest Agricultural & Environmental Science supplemented by targeted internet searching and reference mining yielded 176 reports and publications for title and abstract screening and 65 that met PECO criteria (22 included lethal and 43 included sublethal effects endpoints). Relevant design details (pesticide, test compound configuration, study type, species, sex, exposure duration) were extracted into literature inventory tables to reveal the extent endpoints have been investigated and areas in need of additional research.
Evidence mapping revealed diversity in the pesticides and endpoints studied across the database. However, dilution across bee species, lack of complementary laboratory work and paucity of replicated investigations complicate efforts to interpret and apply available data to support pesticide risk assessment.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
UDP-glucuronosyltransferases (UGT) catalyze the biotransformation of many endobiotics and xenobiotics, and are coded by polymorphic genes. However, knowledge about the effects of these polymorphisms ...is rarely used for the individualization of drug therapy. Here, we present a quantitative systematic review of clinical studies on the impact of UGT variants on drug metabolism to clarify the potential for genotype-adjusted therapy recommendations. Data on UGT polymorphisms and dose-related pharmacokinetic parameters in man were retrieved by a systematic search in public databases. Mean estimates of pharmacokinetic parameters were extracted for each group of carriers of UGT variants to assess their effect size. Pooled estimates and relative confidence bounds were computed with a random-effects meta-analytic approach whenever multiple studies on the same variant, ethnic group, and substrate were available. Information was retrieved on 30 polymorphic metabolic pathways involving 10 UGT enzymes. For irinotecan and mycophenolic acid a wealth of data was available for assessing the impact of genetic polymorphisms on pharmacokinetics under different dosages, between ethnicities, under comedication, and under toxicity. Evidence for effects of potential clinical relevance exists for 19 drugs, but the data are not sufficient to assess effect size with the precision required to issue dose recommendations. In conclusion, compared to other drug metabolizing enzymes much less systematic research has been conducted on the polymorphisms of UGT enzymes. However, there is evidence of the existence of large monogenetic functional polymorphisms affecting pharmacokinetics and suggesting a potential use of UGT polymorphisms for the individualization of drug therapy.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
C-C motif chemokine ligand 2 (CCL2) is a chemoattractant for leukocytes including monocytes, T cells, and natural killer cells and it plays an important role in maintaining the integrity and function ...of the brain. However, there is accumulating evidence that many neurological diseases are attributable to a dysregulation of CCL2 expression. Acquired immune deficiency syndrome (AIDS) encephalopathy is a severe and frequent complication in individuals infected with the human immunodeficiency virus (HIV) or the simian immunodeficiency virus (SIV). The HIV and SIV Nef protein, a progression factor in AIDS pathology, can be transferred by microvesicles including exosomes and tunneling nanotubes (TNT) within the host even to uninfected cells, and Nef can induce CCL2 expression. This review focuses on findings which collectively add new insights on how Nef-induced CCL2 expression contributes to neurotropism and neurovirulence of HIV and SIV and elucidates why adjuvant targeting of CCL2 could be a therapeutic option for HIV-infected persons.
We show that extremely poor, war-affected women in northern Uganda have high returns to a package of $150 cash, five days of business skills training, and ongoing supervision. Sixteen months after ...grants, participants doubled their microenterprise ownership and incomes, mainly from petty trading. We also show these ultrapoor have too little social capital, but that group bonds, informal insurance, and cooperative activities could be induced and had positive returns. When the control group received cash and training 20 months later, we varied supervision, which represented half of the program costs. A year later, supervision increased business survival but not consumption.
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BFBNIB, CEKLJ, NMLJ, NUK, ODKLJ, PNG, UL, UM, UPUK
Summary
Recent methodological advancements in determining the nonexchangeable hydrogen isotopic composition (δ2Hne) of plant carbohydrates make it possible to disentangle the drivers of hydrogen ...isotope (2H) fractionation processes in plants.
Here, we investigated the influence of phylogeny on the δ2Hne of twig xylem cellulose and xylem water, as well as leaf sugars and leaf water, across 73 Northern Hemisphere tree and shrub species growing in a common garden.
2H fractionation in plant carbohydrates followed distinct phylogenetic patterns, with phylogeny reflected more in the δ2Hne of leaf sugars than in that of twig xylem cellulose. Phylogeny had no detectable influence on the δ2Hne of twig or leaf water, showing that biochemistry, not isotopic differences in plant water, caused the observed phylogenetic pattern in carbohydrates. Angiosperms were more 2H‐enriched than gymnosperms, but substantial δ2Hne variations also occurred at the order, family, and species levels within both clades. Differences in the strength of the phylogenetic signals in δ2Hne of leaf sugars and twig xylem cellulose suggest that the original phylogenetic signal of autotrophic processes was altered by subsequent species‐specific metabolism.
Our results will help improve 2H fractionation models for plant carbohydrates and have important consequences for dendrochronological and ecophysiological studies.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
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