Influence of humus forming materials of different nitrogen-carbon ratios on bacterial activities

The determination of the nitrogen-carbon ratio in soils is now considered of much importance in fertility studies. Not only does it show the organic matter content of soils more accurately than the more or less arbitrary humus determinations, concerning which considerable difference of opinion exists, but it also throws some light on the rate at which decomposition processes are occurring

Educating Students with Autism Spectrum Disorders: Is Teacher Certification Area Associated with Academic Outcomes?

Although typically taught by special educators, few studies have examined if certification area is associated with academic outcomes for students with autism spectrum disorders (ASDs). The purpose of this study was to determine whether students with ASD scored better on language arts and mathematics state assessments depending on teacher certification, and whether these associations varied by assessment type. We analyzed 3 years of state administrative data from students with ASD in grades 4–8 receiving special education services. Results showed students taking the regular or alternate assessment had similar academic outcomes regardless of teacher certification. Students who were taught by special education certified teachers and took the modified assessment had lower academic outcomes. Implications for practice, policy, and research are discussed

Visualization of oxygen distribution patterns caused by coral and algae.

Planar optodes were used to visualize oxygen distribution patterns associated with a coral reef associated green algae (Chaetomorpha sp.) and a hermatypic coral (Favia sp.) separately, as standalone organisms, and placed in close proximity mimicking coral-algal interactions. Oxygen patterns were assessed in light and dark conditions and under varying flow regimes. The images show discrete high oxygen concentration regions above the organisms during lighted periods and low oxygen in the dark. Size and orientation of these areas were dependent on flow regime. For corals and algae in close proximity the 2D optodes show areas of extremely low oxygen concentration at the interaction interfaces under both dark (18.4 ± 7.7 µmol O2 L(- 1)) and daylight (97.9 ± 27.5 µmol O2 L(- 1)) conditions. These images present the first two-dimensional visualization of oxygen gradients generated by benthic reef algae and corals under varying flow conditions and provide a 2D depiction of previously observed hypoxic zones at coral algae interfaces. This approach allows for visualization of locally confined, distinctive alterations of oxygen concentrations facilitated by benthic organisms and provides compelling evidence for hypoxic conditions at coral-algae interaction zones

How Perpetrator Identity (Sometimes) Influences Media Framing Attacks as “Terrorism” or “Mental Illness”

Do media frame attacks with Muslim perpetrators as “terrorism” and attacks with White perpetrators as the result of “mental illness”? Despite public speculation and limited academic work with relatively small subsets of cases, there have been no systematic analyses of potential biases in how media frame terrorism. We addressed this gap by examining the text of print news coverage of all terrorist attacks in the United States between 2006 and 2015. Controlling for fatalities, affiliation with a group, and existing mental illness, the odds that an article references terrorism are approximately five times greater for a Muslim versus a non-Muslim perpetrator. In contrast, the odds that an article references mental illness do not significantly differ between White and non-White perpetrators. Results partially confirm public speculation and are robust against numerous alternative explanations. Differences in media framing can influence public (mis)perceptions of violence and threats, and ultimately harm counterterrorism policy

Why Do Some Terrorist Attacks Receive More Media Attention Than Others?

Terrorist attacks often dominate news coverage as reporters seek to provide the public with information. Yet, not all incidents receive equal attention. Why do some terrorist attacks receive more media coverage than others? We argue that perpetrator religion is the largest predictor of news coverage, while target type, being arrested, and fatalities will also impact coverage. We examined news coverage from LexisNexis Academic and CNN.com for all terrorist attacks in the United States between 2006 and 2015 (N=136). Controlling for target type, fatalities, and being arrested, attacks by Muslim perpetrators received, on average, 357% more coverage than other attacks. Our results are robust against a number of counterarguments. The disparities in news coverage of attacks based on the perpetrator’s religion may explain why members of the public tend to fear the “Muslim terrorist” while ignoring other threats. More representative coverage could help to bring public perception in line with reality

When Data Do Not Matter: Exploring Public Perceptions of Terrorism

Public perceptions of terrorism are out of line with reality. How can perceptions be changed? Using a 4 × 2 experimental design with a national sample of U.S. adults, we examine how source of information and details provided impact views of terrorism. Sources, details, and individual-level factors—Islamophobia, trust in media, and trust in science—impact perceived accuracy of terrorism data. Many people updated their views on terrorism after reading factual information, yet only trust in science was related with this change. In short, people can be persuaded by factual information on terrorism, but it is less clear why they change beliefs

A High Fraction of Ly-alpha-Emitters Among Galaxies with Extreme Emission Line Ratios at z ~ 2

Star-forming galaxies form a sequence in the [OIII]/H-beta vs. [NII]/H-alpha diagnostic diagram, with low metallicity, highly ionized galaxies falling in the upper left corner. Drawing from a large sample of UV-selected star-forming galaxies at z~2 with rest-frame optical nebular emission line measurements from Keck-MOSFIRE, we select the extreme ~5% of the galaxies lying in this upper left corner, requiring log([NII]/H-alpha) = 0.75. These cuts identify galaxies with 12 + log(O/H) <~ 8.0, when oxygen abundances are measured via the O3N2 diagnostic. We study the Ly-alpha properties of the resulting sample of 14 galaxies. The mean (median) rest-frame Ly-alpha equivalent width is 39 (36) A, and 11 of the 14 objects (79%) are Ly-alpha-emitters (LAEs) with W_Lya > 20 A. We compare the equivalent width distribution of a sample of 522 UV-selected galaxies at 2.0<z<2.6 identified without regard to their optical line ratios; this sample has mean (median) Ly-alpha equivalent width -1 (-4) A, and only 9% of these galaxies qualify as LAEs. The extreme galaxies typically have lower attenuation at Ly-alpha than those in the comparison sample, and have ~50% lower median oxygen abundances. Both factors are likely to facilitate the escape of Ly-alpha: in less dusty galaxies Ly-alpha photons are less likely to be absorbed during multiple scatterings, while the harder ionizing spectrum and higher ionization parameter associated with strong, low metallicity star formation may reduce the covering fraction or column density of neutral hydrogen, further easing Ly-alpha escape. The use of nebular emission line ratios may prove useful in the identification of galaxies with low opacity to Ly-alpha photons across a range of redshifts.Comment: 12 pages, 5 figures, 2 tables. Accepted for publication in Ap

Algebraic arctic curves in the domain-wall six-vertex model

The arctic curve, i.e. the spatial curve separating ordered (or `frozen') and disordered (or `temperate) regions, of the six-vertex model with domain wall boundary conditions is discussed for the root-of-unity vertex weights. In these cases the curve is described by algebraic equations which can be worked out explicitly from the parametric solution for this curve. Some interesting examples are discussed in detail. The upper bound on the maximal degree of the equation in a generic root-of-unity case is obtained.Comment: 15 pages, no figures; v2: metadata correcte