Backwater controls of avulsion location on deltas

River delta complexes are built in part through repeated river-channel avulsions, which often occur about a persistent spatial node creating delta lobes that form a fan-like morphology. Predicting the location of avulsions is poorly understood, but it is essential for wetland restoration, hazard mitigation, reservoir characterization, and delta morphodynamics. Following previous work, we show that the upstream distance from the river mouth where avulsions occur is coincident with the backwater length, i.e., the upstream extent of river flow that is affected by hydrodynamic processes in the receiving basin. To explain this observation we formulate a fluvial morphodynamic model that is coupled to an offshore spreading river plume and subject it to a range of river discharges. Results show that avulsion is less likely in the downstream portion of the backwater zone because, during high-flow events, the water surface is drawn down near the river mouth to match that of the offshore plume, resulting in river-bed scour and a reduced likelihood of overbank flow. Furthermore, during low-discharge events, flow deceleration near the upstream extent of backwater causes enhanced deposition locally and a reduced channel-fill timescale there. Both mechanisms favor preferential avulsion in the upstream part of the backwater zone. These dynamics are fundamentally due to variable river discharges and a coupled offshore river plume, with implications for predicting delta response to climate and sea level change, and fluvio-deltaic stratigraphy

International Capital Mobility in Developing Countries vs. Industrial Countries: What do Saving-Investment Correlations Tell Us?

The finding of Feldstein and Horioka (1980) that countriesf investment rates are highly correlated with their national saving rates has by now been confirmed by many subsequent studies, even though their inference that international capital mobility nust be low has not been as widely accepted. This paper examines the statistical relationship between national saving and investment in a sample that includes not only 14 industrialized countries, but also 50 developing countries. The paper addresses some of the econometric critiques that have been aimed at the Feldstein-Horioka work. Contrary to what one would expect from consideration of capital mobility, the coefficient appears higher for industrialized countries than for developing countries, and higher after 1973 than before. Our interpretation of the saving-investment evidence is that the hypothesis of a high degree of substitutability for claims on physical capital located in different countries is not supported by the data. International substitutability for financial capital may be nigh, but this is a separate condition (which is properly tested by looking directly at rates of return). High international substitutability for bonds would imply high international substitutability for physical capital if capital were perfectly substitutable for bonds within each country, but there is no reason for this to hold, any more than there is for all goods to be perfect substitutes.

Effects of the private-label invasion in food industries

Using supermarket scanner data, we test a variety of hypotheses from trade journals about the invasion of private-label food products. According to conventional industry wisdom, name-brand firms defended their brands against new private-label products by lowering their prices, engaging in additional promotional activities, and increasingly differentiating their products. Our empirical evidence is inconsistent with these beliefs.private label; entry; price; promotional activity; differentiation; supermarket

An Ecological Assessment of Property and Violent Crime Rates Across a Latino Urban Landscape: The Role of Social Disorganization and Institutional Anomie Theory

The present research put forth an integrated theoretical framework aimed at providing a more holistic community- level approach explaining crime across a heavily populated Latino city. Guided by social disorganization and institutional anomie theory, this study used several data sources and OLS regression techniques to examine the impact of social disorganization, economic and noneconomic institutional characteristics on rates of property and violent crime across 1,016 census block groups in San Antonio, Texas. While several findings emerged, interactions between alcohol density and concentrated disadvantage were significant and positively associated with property and violent crime. Interactions between welfare generosity and concentrated disadvantage were significant and negatively associated with the outcomes

Predicting DeKalb County Drug Court Graduation

INTRODUCTION: Substance abuse is a public health problem in the United States. Though substance abuse is a public health issue in the United States, citizens with substance use disorders have a variety of treatment options. Moreover, there is a close relationship between substance abuse and crime. Consequently, due to an overwhelming number of offenders with substance abuse problems, drug courts were created to combat substance use disorders. Though drug courts are effective in combating substance abuse problems, graduation rates from some drug courts are not as high as they could be; this could be due to a range of factors. AIM: The aim of this study was to examine predictors of graduation from a drug court program using demographic data and risk data assessed via the Level of Service Inventory-Revised (LSI-R). The purpose of the study is to discover if race, age, marital status, high school graduation status, drug of choice, and LSI-R scores are predictors of drug court graduation. METHODS: This cross-sectional study included 665 participants from the DeKalb County Drug Court. Data was collected on each participant at intake including the demographic variables, age, race, education, marital status, and primary drug of choice, along with level of psychosocial risk assessed via the Level of Service Inventory-Revised (LSI-R). Logistic regression analyses were used to predict graduation from the Dekalb County Drug Court. RESULTS: The overall DeKalb County Drug Court graduation rate was 45%. LSI-R scores as well as age at entry were both significant predictors of graduating (p \u3c .05) while the variables of race, marital status, drug of choice, and high school graduation status were not. For every one year increase in age of entry, the odds of a participant graduating from the DeKalb County Drug Court increased by 5%. Also, for every one unit increase in LSI-R score, the odds of graduating from the Dekalb County Drug Court decreased by 5%. Graduation rates varied by drug of choice. Only 29.78% (14/47) whose primary drug of choice was an opioid graduated from the DeKalb County Drug Court program, while participants whose drug of choice was methamphetamine were the most likely to graduate with 56.25% (18/32). Crack/cocaine was 2nd highest with 49.49% (97/196) of participants graduating. DISCUSSION: These findings suggest that LSI-R scores and age are predictors of graduation from the DeKalb County Drug Court. Crack/cocaine and methamphetamine were the drugs with highest likelihood of DeKalb County Drug Court graduation, which is inconsistent with previous studies regarding drug of choice and drug court graduation. Race was not a predictor of DeKalb County Drug Court graduation, implying whites and nonwhites graduated from the drug court at similar rates, which is inconsistent with previous research. Additional resources may be needed to help younger clients graduate from drug court. CONCLUSION: Both age and LSI-R scores were predictors of graduation from the DeKalb County Drug Court program. This study has validated the use of the LSI-R as an assessment tool for DeKalb County Drug County entrance. Special interventions may be needed for younger clients to assist them with drug court graduation

Identifying capacitive and inductive loss in lumped element superconducting hybrid titanium nitride/aluminum resonators

We present a method to systematically locate and extract capacitive and inductive losses in superconducting resonators at microwave frequencies by use of mixed-material, lumped element devices. In these devices, ultra-low loss titanium nitride was progressively replaced with aluminum in the inter-digitated capacitor and meandered inductor elements. By measuring the power dependent loss at 50 mK as the Al-TiN fraction in each element is increased, we find that at low electric field, i.e. in the single photon limit, the loss is two level system in nature and is correlated with the amount of Al capacitance rather than the Al inductance. In the high electric field limit, the remaining loss is linearly related to the product of the Al area times its inductance and is likely due to quasiparticles generated by stray radiation. At elevated temperature, additional loss is correlated with the amount of Al in the inductance, with a power independent TiN-Al interface loss term that exponentially decreases as the temperature is reduced. The TiN-Al interface loss is vanishingly small at the 50 mK base temperature.Comment: 10 pages, 5 figure

Constructing Crime: Neighborhood Characteristics and Police Recording Behavior

It has long been acknowledged that police officers have substantial levels of discretion in their day-to-day activities. There is a well developed body of literature that considers how this discretion is exercised across a broad array of situations including the decision to arrest, use force, and grant citizen requests for official action. Using both social disorganization and conflict theories as conceptual models, the purpose of this study was to determine if neighborhood characteristics affect police reporting behavior across a wide cross-section of reported call types. The findings indicated that reporting behavior widely varies across crime types with a greater percentage of more serious crimes translated into official crime. Neighborhood characteristics did affect reporting practices, but surprisingly only for more serious forms of disorder where discretion was perceived to be less. The findings lent support for both social disorganization and conflict theories. Theoretical implications are discussed

High-Density Suspensions Formed Under Waves

We performed a series of laboratory experiments to investigate the interactions of a turbulent wave boundary layer with a predominantly silt-size sediment bed. Quasi-steady, turbulent, high-density suspensions (HDS) formed over a wide range of wave conditions and had near-bed (~1 mm above bed) concentrations ranging from 17 to 81 g/l scaling roughly with the wave orbital velocity. HDS were defined by the presence of a lutocline, an abrupt change in vertical concentration gradient. Despite the initial bed being 70% silt and 20% sand, HDS had significant near-bed sand fractions ranging from 27 to 78%. Winnowing of the bed caused more concentrated HDS to be coarser grained, which in turn caused the suspensions to be thinner because of the greater settling velocity of the sediment. Our experiments are consistent with a dynamic feedback model where suspended sediment is limited through sediment-induced stratification expressed with a bulk Richardson number. However, our computed values of the bulk Richardson number converge to a value that is an order of magnitude less than the critical value of 0.25 that is typically assumed. The experimental wave orbital velocities (15–60 cm/s) and periods (3–8 s), as well as the characteristics of the HDS and the bed in our experiments, were comparable to observations made on the Eel shelf, California, during storm conditions when fluid mud has been observed