The additionality of R&D tax policy: Quasi-experimental evidence

Despite the prevalence of R&D tax incentives, the amount of additional investment induced by each dollar of tax revenue forgone remains contested. It is notoriously difficult to identify the impact of R&D tax incentives because all firms are potentially eligible and because benefit and investment are jointly determined. Using comprehensive, firm-level data, we apply difference-in-difference analysis around a significant policy reform in Australia in 2012. We find that firms invest an additional $1.90 for every dollar of tax revenue forgone

Moralizing Gods and Armed Conflict

This study documents a robust empirical pattern between moralizing gods, which prescribe fixed laws of morality, and conflict prevalence and fatalities, using spatially referenced data for Africa on contemporary conflicts and ancestral belief systems of individual ethnic groups prior to European contact. Moralizing gods are found to significantly increase conflict prevalence and casualties at the local level. The identification strategy draws on the evolutionary psychology roots of moralizing gods as a solution to the collective action problem in pre-modern societies. A one standard deviation increase in the likelihood of emergence of a moralizing god increases casualties by 18 to 36% and conflict prevalence by 4 to 8% approximately

Combinations of nisin with salt (NaCl) to control Listeria monocytogenes on sheep natural sausage casings stored at 6°C

This study evaluated the effect of combinations of nisin with salt (NaCl) to control Listeria monocytogenes on sheep natural sausage casings. Casings were inoculated with 3.0 x 105 cfu/g final inocula of L. monocytogenes, stored at 6°C in different solutions of nisin at 0, 100, 150 and 200 ìg/g.Each combined with salt at 0, 4, 7 and 12% (w/v). Samples were taken at day 0, 10, 20, 35, 60 and 90 post-inoculation and the number of bacteria present was determined. The bactericidal effect of nisin against L. monocytogenes cells was evident where nisin was applied in combination with salts. In all treatments, nisin/salt mixtures induced a bacterial growth inhibitory effect greater than salt alone. These results indicate that nisin and salt synergistically and significantly inhibit the growth of L.monoctogenes in sheep natural casings. The use of nisin combined with salt as antibacterial agent will be appropriate for applications on natural sausage casing industries as natural preservatives to control foodborne pathogens. They can be used as growth inhibitors of L. monocytogenes, an important foodborne pathogens and spoiling bacterium. The main reason for their appropriateness is their natural origin, which consumers find comforting. These beneficial characteristics could increase casings safety and shelf life

Response of sugarcane (Saccharum sp.) varieties to embryogenic callus induction and in vitro salt stress

Response of three varieties of sugarcane (Saccharum sp.) to callus induction, embryogenic callus production and in vitro salt tolerance was studied. For callus induction and embryogenic callus production, leaf bases segments were subjected to in vitro culture on Murashige and Skoog (MS) medium supplemented with 3 mg 1-1 2,4 Dichlorophenoxyacetic acid for 4 weeks. To evaluate salt tolerance of the varieties, growing calli were exposed after two subsequent subcultures (4 weeks each) to different concentrations of NaCl (0, 17, 34, 68 and 102 mM) added to the culture medium for 4 weeks. Comparision of genotypes was based on callus induction percentage, embryogenic callus production percentage and relative fresh weight growth (RFWG). For salt tolerance, necrosis percentage and relative fresh weight growth of callus were used. The three varieties responded well to callus induction with a percentage of induction about 82, 84 and 100% for CP70-321, NCo310 and CP65-357, respectively. The high percentages of embryogenic callus obtained for the three varieties indicated that these varieties have a high capacity for embryogenic callus production. Relative fresh weight growth of callus was about 1.076, 1.282 and 0.925 for CP70-321, NCo310 and CP65-357, respectively. NaCl effect resulted in calli necrosis and a reduction of their growth. However, growing calli derived from varieties CP70-321 and NCo310 showed less necrosis percentages and less relative fresh weight growth reduction under salt stress. They appeared to be more salt tolerant in vitro than CP65-357.African Journal of Biotechnology Vol. 4 (4), pp. 350-354, 200

Free proline, soluble sugars and soluble proteins concentration as affected by salt stress in two sugarcane (Saccharum sp.) cultivars differing in their salt tolerance

Salt stress is one of the environmental stresses which affect negatively the agricultural production of the world. In this study, the effects of salt stress on free proline, soluble sugars and soluble proteins accumulation were investigated in two sugarcane (Saccharum sp.) cultivars: CP66-346 (salt- tolerant) and CP65-357 (salt-sensitive). Young plants of these cultivars were exposed, in a hydroponic system, to four concentrations of NaCl (0, 17, 34 and 68 mM). These concentrations correspond to an electric conductivity of 1; 2.83; 4.26 and 6.63 mS/cm, respectively. Free proline, soluble sugars and proteins accumulation were quantified after 2 weeks of stress. Proline and soluble sugars concentrations increased significantly in leaves and roots under salinity. Furthermore, NaCl caused an increase in soluble proteins concentration in leaves and roots of the tolerant cultivar CP66-346 and a decrease in leaves and roots of the sensitive CP65-357. Salttolerant CP66-346 plants accumulated more soluble sugars in leaves than CP65-357, while both cultivars accumulated similar quantities of proline in leaves. These results provided evidence that soluble sugars could contribute mainly to counteract the negative water potential of the outside medium and that protein synthesis stimulation was implicated in sugarcane salt tolerance. Proline appeared as a symptom in salt-stressed sugarcane plants rather than as an indicator of tolerance.Keywords: Sugarcane, Saccharum sp., proline, soluble sugars, soluble proteins, salt-toleranc

Early COVID-19 Government Communication Is Associated With Reduced Interest in the QAnon Conspiracy Theory

Does inadequate risk communication during uncertain times trigger the rise of conspiratorial ideas? We hypothesize that, where government COVID-19 risk communication started early, as measured by the number of days between the start of the communication campaign and the first case in the country, citizens are less likely to turn to conspiratorial explanations for the pandemic, which typically assign blame to powerful actors with secret interests. In Study 1a, we find strong support for our hypothesis in a global sample of 111 countries, using daily Google search volumes for QAnon as a measure of interest in QAnon, which is a conspiracy theory contending, among other things, that COVID-19 is a conspiracy orchestrated by powerful actors and aimed at repressing civil liberties. The effect is robust to a variety of sensitivity checks. In Study 1b, we show that the effect is not explainable by pre-pandemic cross-country differences in QAnon interest, nor by ‘secular’ rising interest in QAnon amid the pandemic. A one-standard deviation (26.2days) increase in communication lateness is associated with a 26% increase in QAnon interest. In pre-registered Study 2, we find limited support for the proposition that early communication reduces self-reported pandemic-related conspiratorial ideation in a sample of respondents from 51 countries. Overall, our results provide evidence that interest in extreme ideas, like QAnon, are highly responsive to government risk communication, while less extreme forms of conspiracism are perhaps less so

Risk Attitudes and Human Mobility during the COVID-19 Pandemic

Behavioral responses to pandemics are less shaped by actual mortality or hospitalization risks than they are by risk attitudes. We explore human mobility patterns as a measure of behavioral responses during the COVID-19 pandemic. Our results indicate that risk-taking attitude is a critical factor in predicting reduction in human mobility and increase social confinement around the globe. We find that the sharp decline in movement after the WHO (World Health Organization) declared COVID-19 to be a pandemic can be attributed to risk attitudes. Our results suggest that regions with risk-averse attitudes are more likely to adjust their behavioral activity in response to the declaration of a pandemic even before most official government lockdowns. Further understanding of the basis of responses to epidemics, e.g., precautionary behavior, will help improve the containment of the spread of the virus

Slowly Varying Regression under Sparsity

We consider the problem of parameter estimation in slowly varying regression models with sparsity constraints. We formulate the problem as a mixed integer optimization problem and demonstrate that it can be reformulated exactly as a binary convex optimization problem through a novel exact relaxation. The relaxation utilizes a new equality on Moore-Penrose inverses that convexifies the non-convex objective function while coinciding with the original objective on all feasible binary points. This allows us to solve the problem significantly more efficiently and to provable optimality using a cutting plane-type algorithm. We develop a highly optimized implementation of such algorithm, which substantially improves upon the asymptotic computational complexity of a straightforward implementation. We further develop a heuristic method that is guaranteed to produce a feasible solution and, as we empirically illustrate, generates high quality warm-start solutions for the binary optimization problem. We show, on both synthetic and real-world datasets, that the resulting algorithm outperforms competing formulations in comparable times across a variety of metrics including out-of-sample predictive performance, support recovery accuracy, and false positive rate. The algorithm enables us to train models with 10,000s of parameters, is robust to noise, and able to effectively capture the underlying slowly changing support of the data generating process.Comment: Submitted to Operations Research. First submission: 02/202