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What does it take for warnings about violent conflict and war to be listened to, believed and acted upon? Why are warnings from some sources noticed and largely accepted, while others are ignored or disbelieved? These questions are central to considering the feasibility of preventing harm to the economic and security interests of states. Challenging conventional accounts that tend to blame decision-makers' lack of receptivity and political will, the authors offer a new theoretical framework explaining how distinct 'paths of persuasion' are shaped by a select number of factors, including conflict characteristics, political contexts, and source-recipient relations. This is the first study to systematically integrate persuasion attempts by analysts, diplomats and senior officials with those by journalists and NGO staff. Its ambitious comparative design encompasses three states (the US, UK, and Germany) and international organisations (the UN, EU, and OSCE) and looks in depth at four conflict cases: Rwanda (1994), Darfur (2003), Georgia (2008) and Ukraine (2014).
Risk populations for HIV infections tend to neglect condom use, making alternative preventive approaches necessary. Accordingly, we modelled the risk of sexual HIV transmission for condom use vs. use of rapid diagnostic test (RDT) systems with subsequent exclusion of potential sexual partners with a correctly or falsely positive test from unprotected sex with and without the use of HIV pre-exposure prophylaxis (PrEP) in a bio-statistical approach. We combined a previously described model of transmission risk for HIV-exposed individuals with a newly suggested model of risk of HIV exposure for sexually active HIV-negative individuals. The model was adapted for several stages of infection and different strategies of HIV infection prevention.
HIV prevention with RDTs can reduce the transmission risk by up to 97% compared with having sex without any prevention and up to 80% compared with condom use. Nevertheless, RDT-based prevention strategies demonstrate a lack of protection in several stages of infection; in particular, RNA-based RDT systems may fail under treatment. RDT-based pre-screening of potential sex partners prior to unprotected sexual contacts substantially reduces HIV transmission risk. Combination of different prevention strategies is advisable for high-risk groups.
This paper reports the first successful synthesis and the structural characterization of nanocrystalline and stacking-disordered β-cristobalite AlPO4 that is chemically stabilized down to room temperature and free of crystalline impurity phases. Several batches of the title compound were synthesized and thoroughly characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy, selected area electron diffraction, energy dispersive X-ray spectroscopy mapping in SEM, solid-state 31P nuclear magnetic resonance (31P-NMR) spectroscopy including the TRAPDOR method, differential thermal analysis (DTA), gas-sorption methods, optical emission spectroscopy, X-ray fluorescence spectroscopy, and ion chromatography. Parameters that are critical for the synthesis were identified and optimized. The synthesis procedure yields reproducible results and is well documented. A high-quality XRD pattern of the title compound is presented, which was collected with monochromatic copper radiation at room temperature in a wide 2θ range of 5°–100°.
Individuals with chronic respiratory conditions may be at increased risk for pertussis. We conducted a retrospective administrative claims analysis to examine the incidence and economic burden of diagnosed pertussis among adolescents and adults in the USA with chronic obstructive pulmonary disease (COPD) or asthma. Patients aged ⩾11 years with diagnosed pertussis and pre-existing COPD (n = 343) or asthma (n = 1041) were matched 1:1 to patients with diagnosed pertussis but without COPD or asthma. Differences in all-cause costs (‘excess’ costs) during the 45-day and 3-month and 6-month periods before and after the pertussis index date were calculated; adjusted excess costs were estimated via multivariate regressions. The incidence of diagnosed pertussis was higher among patients with COPD or asthma than among matched patients. Compared with matched patients, patients with pertussis and pre-existing COPD or asthma accrued greater all-cause adjusted costs across study periods ($3694 and $1193 more, respectively, in the 45-day period; $4173 and $1301 more in the 3-month period; and $6154 and $1639 more in the 6-month period; all P < 0·0001). Patients with pre-existing COPD or asthma experience an increased economic burden after diagnosed pertussis and may especially benefit from targeted tetanus, diphtheria, and acellular pertussis vaccination strategies.
The S-band Polarisation All-Sky Survey has observed the entire southern sky using the 64-m Parkes radio telescope at 2.3 GHz with an effective bandwidth of 184 MHz. The surveyed sky area covers all declinations δ ⩽ 0°. To analyse compact sources, the survey data have been re-processed to produce a set of 107 Stokes I maps with 10.75 arcmin resolution and the large scale emission contribution filtered out. In this paper, we use these Stokes I images to create a total intensity southern-sky extragalactic source catalogue at 2.3 GHz. The source catalogue contains 23 389 sources and covers a sky area of 16 600 deg2, excluding the Galactic plane for latitudes |b| < 10°. Approximately, 8% of catalogued sources are resolved. S-band Polarisation All-Sky Survey source positions are typically accurate to within 35 arcsec. At a flux density of 225 mJy, the S-band Polarisation All-Sky Survey source catalogue is more than 95% complete, and ~ 94% of S-band Polarisation All-Sky Survey sources brighter than 500 mJy beam−1 have a counterpart at lower frequencies.
Johnsongrass populations that are resistant to 5-enolpyruvyl-3-shikimate synthase (EPSPS)–, acetyl coenzyme A carboxylase (ACCase)–, or acetolactate synthase (ALS)–inhibiting herbicides are increasingly common throughout the midsouth. Three trials were conducted in 2012, 2013, and 2014 in Fayetteville, AR and Alexandria, LA to evaluate strategies with and without ALS- and ACCase inhibitors for management of rhizomatous johnsongrass in the absence of glyphosate. Fluometuron or fluometuron plus pyrithiobac applied PRE followed by (fb) EPOST, MPOST, and LAYBY tank mixtures containing multiple effective mechanisms of action (MOA) controlled johnsongrass at least 90%. Simplifying the program by removing a herbicide or eliminating an application timing reduced control, and increased vegetative and sexual reproduction of johnsongrass. To manage severe infestations or escapes glufosinate plus clethodim fb glufosinate plus clethodim or clethodim plus pyrithiobac fb clethodim) effectively controlled 15-cm johnsongrass. However, johnsongrass control was reduced when ALS and ACCase inhibitors were tank mixed, especially for the second POST application, compared to ACCase inhibitors alone. Effective herbicide programs are available to growers to control johnsongrass in the absence of glyphosate, but the use of PRE herbicides followed by multiple applications of POST herbicides is critical for successful management.
Primiparous ewes (n=32) were assigned to dietary treatments in a 2×2 factorial arrangement to determine effects of nutrient restriction and melatonin supplementation on maternal and fetal pancreatic weight, digestive enzyme activity, concentration of insulin-containing clusters and plasma insulin concentrations. Treatments consisted of nutrient intake with 60% (RES) or 100% (ADQ) of requirements and melatonin supplementation at 0 (CON) or 5 mg/day (MEL). Treatments began on day 50 of gestation and continued until day 130. On day 130, blood was collected under general anesthesia from the uterine artery, uterine vein, umbilical artery and umbilical vein for plasma insulin analysis. Ewes were then euthanized and the pancreas removed from the ewe and fetus, trimmed of mesentery and fat, weighed and snap-frozen until enzyme analysis. In addition, samples of pancreatic tissue were fixed in 10% formalin solution for histological examination including quantitative characterization of size and distribution of insulin-containing cell clusters. Nutrient restriction decreased (P⩽0.001) maternal pancreatic mass (g) and α-amylase activity (U/g, kU/pancreas, U/kg BW). Ewes supplemented with melatonin had increased pancreatic mass (P=0.03) and α-amylase content (kU/pancreas and U/kg BW). Melatonin supplementation decreased (P=0.002) maternal pancreatic insulin-positive tissue area (relative to section of tissue), and size of the largest insulin-containing cell cluster (P=0.04). Nutrient restriction decreased pancreatic insulin-positive tissue area (P=0.03) and percent of large (32 001 to 512 000 µm2) and giant (⩾512 001 µm2) insulin-containing cell clusters (P=0.04) in the fetus. Insulin concentrations in plasma from the uterine vein, umbilical artery and umbilical vein were greater (P⩽0.01) in animals receiving 100% requirements. When comparing ewes to fetuses, ewes had a greater percentage of medium insulin-containing cell clusters (2001 to 32 000 µm2) while fetuses had more (P<0.001) pancreatic insulin-positive area (relative to section of tissue) and a greater percent of small, large and giant insulin-containing cell clusters (P⩽0.02). Larger insulin-containing clusters were observed in fetuses (P<0.001) compared with ewes. In summary, the maternal pancreas responded to nutrient restriction by decreasing pancreatic weight and activity of digestive enzymes while melatonin supplementation increased α-amylase content. Nutrient restriction decreased the number of pancreatic insulin-containing clusters in fetuses while melatonin supplementation did not influence insulin concentration. This indicated using melatonin as a therapeutic agent to mitigate reduced pancreatic function in the fetus due to maternal nutrient restriction may not be beneficial.
In this paper we investigate the physical processes that lead to the growth and decay of magnetic flux in and near sunspots.
An initial phase of rapid growth is characterized by the emergence of magnetic flux from the deep convection zone. As the flux rope rises through the surface the magnetic field is swept to the junctions of the supergranular network where sunspots are formed. These flux concentrations follow the footpoints of the emergent flux rope as they rapidly move apart.
We present four wave mixing experiments on GaN. We find an intrinsic homogeneous broadening of the A-exciton of 1.67 meV. A pronounced beating with a period of 0.52 ps is observed at excitation energies between the A- and the B-exciton and corresponds to an energy splitting of 7.98 meV of A- and B-exciton.
We investigated an outbreak of 396 Salmonella enterica serotype I 4,5,12:i:- infections to determine the source. After 7 weeks of extensive hypothesis-generation interviews, no refined hypothesis was formed. Nevertheless, a case-control study was initiated. Subsequently, an iterative hypothesis-generation approach used by a single interviewing team identified brand A not-ready-to-eat frozen pot pies as a likely vehicle. The case-control study, modified to assess this new hypothesis, along with product testing indicated that the turkey variety of pot pies was responsible. Review of product labels identified inconsistent language regarding preparation, and the cooking instructions included undefined microwave wattage categories. Surveys found that most patients did not follow the product's cooking instructions and did not know their oven's wattage. The manufacturer voluntarily recalled pot pies and improved the product's cooking instructions. This investigation highlights the value of careful hypothesis-generation and the risks posed by frozen not-ready-to-eat microwavable foods.
Dietary melatonin supplementation during mid- to late-gestation increased umbilical artery blood flow and caused disproportionate fetal growth. This melatonin-induced increase in umbilical artery blood flow may alter nutrient availability to the fetus, which may lead to alterations in fetal size. The objectives of the current experiment were to determine amino acid (AA) and glucose concentrations as well as AA and glucose flux across the uteroplacenta using a mid- to late-gestation model of intrauterine growth restriction supplemented with dietary melatonin as a 2 × 2 factorial design. At day 50 of gestation, 32 ewes were supplemented with 5 mg of melatonin (MEL) or no melatonin (CON) and were allocated to receive 100% (adequate; ADQ) or 60% (restricted; RES) of nutrient requirements. On day 130 of gestation, uterine and umbilical blood flows were determined via Doppler ultrasonography during a non-survival surgery. Blood samples were collected under general anesthesia from the maternal saphenous artery, gravid uterine vein, umbilical artery, and umbilical vein for AA analysis and glucose. Total α-AA concentrations in maternal artery and gravid uterine vein were decreased (P < 0.05) in RES v. ADQ fed ewes. Maternal arterial − venous difference in total α-AA was increased (P ⩽ 0.01) in RES v. ADQ fed ewes, while total uterine α-AA flux was not different (P > 0.40) across all treatment groups. Fetal venous − arterial difference in total α-AA as well as uteroplacental flux of total α-AA were decreased (P < 0.05) in CON-RES v. CON-ADQ, and similar (P > 0.20) in MEL-RES v. CON-ADQ. Maternal concentrations and uterine flux of branched-chain AA (BCAA) were not different across all treatment groups; however, fetal uptake of BCAA was decreased (P < 0.05) in CON-RES v. CON-ADQ, and similar (P > 0.20) in MEL-RES v. CON-ADQ. Uterine uptake of glucose was not different (P ⩾ 0.08) across all treatment groups, while uteroplacental uptake of glucose was increased (P ⩽ 0.05) in RES v. ADQ ewes. In conclusion, maternal nutrient restriction increased maternal arterial − venous difference in total α-AA, while total uterine α-AA flux was unaffected by maternal nutrient restriction. Melatonin supplementation did not impact maternal serum concentrations or uterine flux of glucose or AA; however, melatonin did improve fetal BCAA uptake during maternal nutrient restriction.
We assessed characteristics associated with community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) carriage among residents of 22 nursing homes. Of MRSA-positive swabs, 25% (208/824) were positive for CA-MRSA. Median facility CA-MRSA percentage was 22% (range, 0%–44%). In multivariate models, carriage was associated with age less than 65 years (odds ratio, 1.2; P < .001) and Hispanic ethnicity (odds ratio, 1.2; P = .006). Interventions are needed to target CA-MRSA.
We have studied defects in Cz-grown single crystal silicon by utilizing a variable energy positron beam and positron lifetime spectroscopy in conjunction with surface photovoltage measurements. We present results for the depth profile of defects obtained from the Doppler broadening spectra measured by implanting variable energy positrons at different depths ranging from the surface down to ∼ 1 /xm deep. We have also measured positron lifetime spectra at different locations on a wafer and have obtained a radial variation in the density of the vacancy-type defects.
Resistance switching in metal – insulator - metal (MIM) structures with transition metal oxides as the insulator material is a promising concept for upcoming non-volatile memories. The electronic properties of transition metal oxides can be tailored in a wide range by doping and external fields. In this study SrTiO3 single crystals are subjected to high temperature vacuum annealing. The vacuum annealing introduces oxygen vacancies, which act as donor centers. MIM stacks are produced by physical vapor deposition of Au and Ti contacts on the front and rear face of the SrTiO3 crystal. The time dependent forming of the MIM stacks under an external voltage is investigated for crystals with varying bulk conductivities. For continued formation, the resistivity increases up to failure of the system where no current can be measured anymore and switching becomes impossible.
The mechanical, thermal, chemical, and tribological properties of diamond make it an ideal material for the fabrication of MEMS components. However, conventional CVD diamond deposition methods result in either a coarse-grained pure diamond structure that prevents high- resolution patterning, or in a fine-grained diamond film with a significant amount of intergranular non-diamond carbon. At Argonne National Laboratory, we are able to produce phase-pure ultrananocrystalline diamond (UNCD) films for the fabrication of MEMS components. UNCD is grown by microwave plasma CVD using C60-Ar or CH4-Ar plasmas, resulting in films that have 3-5 nm grain size, are 10-20 times smoother than conventionally grown diamond films, and can have mechanical properties similar to that of single crystal diamond. We used lithographic patterning, lift-off, and etching, in conjunction with the capability for growing UNCD on SiO2 to fabricate 2-D and 3-D UNCD-MEMS structures. We have performed initial characterization of mechanical properties by using nanoindentation and in-situ TEM indentor techniques. The values of Hardness (∼88 GPa) and Young's modulus (∼ 864 GPa) measured are very close to those of single crystal diamond (100 GPa and 1000 GPa respectively). The results show that UNCD is a promising material for future high performance MEMS devices.