What limits phytoplankton growth in nature? The answer is elusive because of methodological problems associated with bottle incubations and nutrient addition experiments. We are investigating the possibility that antibodies to proteins repressed by a specific nutrient can be used as probes to indicate which nutrient limits photosynthetic carbon fixation in the ocean. The diatom Phaeodactylum tricornutum Bohlin and the chlorophyte Dunaliella tertiolecta Butcher were grown in batch cultures in artificial seawater and f/2 nutrient lacking either phosphorus, iron, or nitrogen. Chlorosis was induced by nutrient limitation in both species with the exception of phosphorus‐limited D. tertiolecta. The synthesis and appearance of specific proteins were followed by labeling with 14C‐bicarbonate. Nutrient limitation in general leads to a decrease in the quantum efficiency of photosystem II, suggesting that deficiency of any nutrient affects the photosynthetic apparatus to some degree: however, the effect of nitrogen and iron limitation on quantum efficiency is more severe than that of phosphorus. A crude fractionation of the soluble and membrane proteins demonstrated that the large proteins induced under limitation by phosphorus and iron were associated with the membranes. However, small iron‐repressible proteins were located in the soluble fraction. Isolation with anion‐exchange chromatography and N‐terminal sequencing of iron‐repressible, 23‐kDa Proteins from D. tertiolecta, P. tricornutum, and Chaetoceros gracilis revealed that these small soluble proteins have strong homology with the N‐terminal sequence of flavodoxins from Azotobacter and Clostridium. The identity of the flavodoxin from D. tertiolecta was confirmed by immunodetection using antiflavodoxin raised against Chlorella. Flavodoxin was detected only under iron deprivation and was absent from nitrogen‐and phosphorus‐limited algae. Flavodoxin is a prime candidate for a molecular probe of iron limitation in the ocean. The requirements to confirm its utility in nature are discussed.

Using a national probability sample of municipal police departments, this study provides the first systematic look at the prevalence, predictors, and content of municipal police websites in the United States. A content analysis revealed that police agencies with websites (42% of all police agencies nationwide in 2008) were more inclined to use websites to “push out” information rather than “pull in” information from the community. The results support the hypothesis that departments with a greater emphasis on community policing (defined by Law Enforcement Management and Administrative Statistics [LEMAS] data) would be more likely to have a website, exhibit greater transparency in the display of data and provide more opportunities for citizen input. Crime rate and population size were also important determinants of website creation and content, respectively. This study concludes that websites are underutilized by both the police and research communities.

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The purpose of this study was: (1) to assess the impact of an incident of racial profiling on residents' attitudes about profiling; and (2) to examine the effects of exposure to a video clip of deliberation about the incident on residents' beliefs about the causes of profiling. All residents, White and minority, were less likely to believe that Chicago police officers engaged in profiling after the incident. These findings suggest that attitudes about the prevalence of racial profiling are susceptible to the manner in which the media construct incidents of police misconduct. Exposure to the video clip was not related to differences in residents' beliefs about the causes of profiling, but was related to differences in perceptions of the dangerousness of traffic stops. The findings highlight the need for more research on how media constructions of police misconduct influence attitudes about profiling and impact community-police relations.Research findings highlight the salience of race in predicting attitudes toward police, particularly that minorities tend to hold more negative views of police than