Recently, several experiments concerning heat transfer from short pin fins have been conducted with the results indicating lower heat transfer from short pin fins than from longer pin fins found in tube banks and other similar configurations. Assessments of the effect of the number of pin rows and row geometry have also been made. It was felt that there was a need to determine the relative contribution of pin length to diameter ratio and pin row geometry on the heat transfer. Array-averaged heat transfer coefficients on pin and endwall surfaces were measured for two configurations of staggered arrays of short pin fins (length to diameter ratio of 4). One configuration contained eight streamwise rows of pins, while the other contained only four rows. Results showed that both the eight-row and the four-row configurations for an Lp/D of 4 exhibit higher heat transfer than in similar tests on shorter pin fins (Lp/D of 1/2 and 2). It was also found that for this Lp/D ratio the array-averaged heat transfer was slightly higher with eight rows of staggered pins than with only four rows.

Coastal megacities deposit significant amounts of carbon (C), nitrogen (N), and pollutants into surrounding waters. In urbanized estuaries, these inputs, including wastewater discharge and surface runoff, can affect biogeochemical cycles, microbial production, and greenhouse gas (GHG) efflux. To better understand estuarine GHG production and its connection to anthropogenic drivers, we quantified carbon dioxide (CO2) and methane (CH4) surface‐water concentrations and efflux in combination with a suite of biogeochemical parameters, including anthropogenic indicators, in the Hudson River Estuary (HRE) and adjacent waters surrounding New York, NY, over a 2‐yr period. The HRE was a source of both CO2 (33 ± 3 mmol CO2 m−2 d−1) and CH4 (177 ± 22 μmol CH4 m−2 d−1) under all measured conditions. Surface‐water salinity, oxygen saturation, fecal indicator bacteria, nitrate concentrations, and temperature best explained the variance in CO2 and CH4 concentrations in multiple regression analyses, producing robust predictive power for both GHGs. Our multifaceted data set demonstrated that CH4 and CO2 surface concentrations are explained in part by enterococci concentrations, a widely used wastewater biological indicator, explicitly linking wastewater inputs to GHG surface concentrations in the HRE. The greatest CO2 and CH4 surface‐water concentrations were found in urban tributaries and embayments, primary wastewater delivery areas throughout the HRE. Estuarine tributaries and embayments have historically received less research attention than midchannel sites, but since these shallow sites may contribute to increased GHG efflux in anthropogenically impacted estuaries, further study is warranted.

There is considerable theoretical evidence that marijuana should be carcinogenic. However, most reviews have found no direct evidence of chronic marijuana smoking causing lung cancer. Some recent reports implicate marijuana smoking as a cause of cancer of the upper aerodigestive tract, though most of the subjects were exposed to other, possibly confounding, etiologic factors, namely tobacco and alcohol. We report two cases of squamous cell carcinoma of the tongue in men who chronically smoked marijuana but had no other risk factors. The totality of cases may point to a predilection of marijuana smoke for carcinogenesis in the upper aerodigestive tract. This correlates with nonmalignant effects and may be related to a different method of smoking marijuana compared with tobacco.