Southwest Border Violence: Issues in Identifying and Measuring Spillover Violence

[Excerpt] There has been a recent increase in the level of drug trafficking-related violence within and between the drug trafficking organizations in Mexico. This violence has generated concern among U.S. policy makers that the violence in Mexico might spill over into the United States. Currently, U.S. federal officials deny that the recent increase in drug trafficking-related violence in Mexico has resulted in a spillover into the United States, but they acknowledge that the prospect is a serious concern. Currently, no comprehensive, publicly available data exist that can definitively answer the question of whether there has been a significant spillover of drug trafficking-related violence into the United States. Although anecdotal reports have been mixed, U.S. government officials maintain that there has not yet been a significant spillover. In an examination of data that could provide insight into whether there has been a significant spillover in drug trafficking-related violence from Mexico into the United States, CRS analyzed violent crime data from the Federal Bureau of Investigation’s Uniform Crime Report program. The data, however, do not allow analysts to determine what proportion of the violent crime rate is related to drug trafficking or, even more specifically, what proportion of drug trafficking-related violent crimes can be attributed to spillover violence. In conclusion, because the trends in the overall violent crime rate may not be indicative of trends in drug trafficking-related violent crimes, CRS is unable to draw definitive claims about trends in drug trafficking-related violence spilling over from Mexico into the United States. This report will be updated as circumstances warrant

Southwest Border Violence: Issues in Identifying and Measuring Spillover Violence

This report looks at the nature of the U.S.-Mexico drug trafficking conflict and assessments of how the conflict could spill across the border

Organized crime and preventive justice

By comparison with the prevention of terrorism, the prevention of acts of organizedcrime might be thought easier to conceptualize precisely and less controversial to legislate against and police. This impression is correct up to a point, because it is possible to arrive at some general characteristics of organized crime, and because legislation against it is not obviously bedevilled by the risk of violating civil or political rights, as in the case of terrorism. But there is a significant residue of legal, moral and political difficulty: legislation against organized crime is hard to make effective; the harm of organized crime is not uniform, and so some preventive legislation seems too sweeping and potentially unjust. More fundamentally, the scale and rewards of organized crime are often dependent on mass public participation in markets for proscribed goods, which may point to a hidden public consensus in favour of some of what is criminalized. Preventive policing and legislation in both areas, then, are less easily justified than first appears

Southwest Border Violence: Issues in Identifying and Measuring Spillover Violence

This report focuses on how policy makers would identify any spillover of drug trafficking-related violence into the United States. It provides an overview of Mexican drug trafficking organization structures, how they conduct business, and the relationship between the drug trafficking organizations in Mexico and their partnerships operating here in the United States; a discussion of the illicit drug trade between Mexico and the United States; and other related issues

Water oxidation at hematite photoelectrodes: the role of surface states

Hematite (α-Fe2O3) constitutes one of the most promising semiconductor materials for the conversion of sunlight into chemical fuels by water splitting. Its inherent drawbacks related to the long penetration depth of light and poor charge carrier conductivity are being progressively overcome by employing nanostructuring strategies and improved catalysts. However, the physical–chemical mechanisms responsible for the photoelectrochemical performance of this material (J(V) response) are still poorly understood. In the present study we prepared thin film hematite electrodes by atomic layer deposition to study the photoelectrochemical properties of this material under water-splitting conditions. We employed impedance spectroscopy to determine the main steps involved in photocurrent production at different conditions of voltage, light intensity, and electrolyte pH. A general physical model is proposed, which includes the existence of a surface state at the semiconductor/liquid interface where holes accumulate. The strong correlation between the charging of this state with the charge transfer resistance and the photocurrent onset provides new evidence of the accumulation of holes in surface states at the semiconductor/electrolyte interface, which are responsible for water oxidation. The charging of this surface state under illumination is also related to the shift of the measured flat-band potential. These findings demonstrate the utility of impedance spectroscopy in investigations of hematite electrodes to provide key parameters of photoelectrodes with a relatively simple measurement

Cellobiose Dehydrogenase Aryl Diazonium Modified Single Walled Carbon Nanotubes: Enhanced Direct Electron Transfer through a Positively Charged Surface

One of the challenges in the field of biosensors and biofuel cells is to establish a highly efficient electron transfer rate between the active site of redox enzymes and electrodes to fully access the catalytic potential of the biocatalyst and achieve high current densities. We report on very efficient direct electron transfer (DET) between cellobiose dehydrogenase (CDH) from Phanerochaete sordida (PsCDH) and surface modified single walled carbon nanotubes (SWCNT). Sonicated SWCNTs were adsorbed on the top of glassy carbon electrodes and modified with aryl diazonium salts generated in situ from p-aminobenzoic acid and p-phenylenediamine, thus featuring at acidic pH (3.5 and 4.5) negative or positive surface charges. After adsorption of PsCDH, both electrode types showed excellent long-term stability and very efficient DET. The modified electrode presenting p-aminophenyl groups produced a DET current density of 500,mu A cm(-2) at 200 mV vs normal hydrogen reference electrode (NHE) in a 5 mM lactose solution buffered at pH 3.5. This is the highest reported DET value so far using a CDH modified electrode and comes close to electrodes using mediated electron transfer. Moreover, the onset of the electrocatalytic current for lactose oxidation started at 70 mV vs NHE, a potential which is 50 mV lower compared to when unmodified SWCNTs were used. This effect potentially reduces the interference by oxidizable matrix components in biosensors and increases the open circuit potential in biofuel cells. The stability of the electrode was greatly increased compared with unmodified but cross-linked SWCNTs electrodes and lost only 15% of the initial current after 50 h of constant potential scanning