Rights at United States Borders

This article explores protections available under the Fourth and Fifth Amendments to the United States Constitution. Contrary to opinions in popular culture, and perhaps even among Customs officials, powers to search, seize, and interrogate at United States border crossings are not unlimited. In the current world climate of security and threat, a discussion regarding the level of intrusiveness available to a zealous Customs agent appears particularly relevant. The article addresses the requirements for search, seizure, and interrogation, as well as the lawful conditions and limits upon each activity

Effects of Obesity on Thermoregulation and Cardiovascular Function During Exercise in Females

Previous research has shown that obese individuals are at greater risk for heat illnesses because of impaired thermoregulation. However, laboratory studies investigating cardiovascular and thermoregulatory function in obese individuals are difficult to interpret because of low sample sizes and methodological concerns. The purpose of this study was to determine if there are differences in thermoregulatory and cardiovascular function between obese and non-obese females. Twenty-four females, 13 obese (43.3 ± 4 .3 % fat, 77.2 ± 13.7 kg) and 11 non-obese (27.8 ± 6.0 % fat, 55.7±6.7 kg), cycled for 60 min in a warm environment (~40°C, 30% humidity) at a work load that elicited either 300 W of metabolic heat production (fixed heat production; FHP) or 175 W/m2 of skin surface area (body surface area; BSA). In the FHP trial, when heat production was similar between obese (290 ± 16 W) and non-obese (299±18 W) individuals (P \u3e 0.05), no differences in rectal temperature (Tre), mean skin temperature (Tsk), VO2 (l/min), or sweat rate (l/hr) occurred (all P \u3e 0.05). As expected because of greater skin surface area, the obese individuals in the BSA trial had a greater heat production (316±33 W) compared to the non-obese individuals (284 ± 23W) which was a result of higher VO2 during exercise (1.14 ± 0.10 vs. 1.01 ± 0.09 l/min; P \u3e 0.05). The rise in Tre and Tsk, over time in the BSA trial was not dependent on subject grouping (i.e., non-significant interaction P \u3e 0.05). In conclusion, when obese and non-obese individuals exercise at a fixed metabolic heat production or a heat production relative to body surface area there are no thermoregulatory differences between groups. The overall relatively minor increases in Tre (0.55 ± 0.28 and 0.61 ± 0.34°C for FHP and BSA trials, respectively), may partially explain why differences were not observed in this setting

The Effect of Blinded Hydration State on Thermoregulation and Performance in Male Cyclists

Purpose: The purpose of these studies was to observe the effect of dehydration on exercise performance while subjects were blinded to their hydration status. Methods: Study 1: Seven male cyclists (weight: 71±8 kg, body fat: 14±6%, VO2peak: 59.4±6 ml∙kg-1·min-1) exercised for 2 hours on a cycle ergometer at 55% VO2peak, in a hot-dry environment (35°C, 30% rh), with a nasogastric (NG) tube under euhydrated (EUH-NT) and hypohydrated (DEH-NT) conditions. In both trials, thirst was matched by drinking 25 mL every 5 min. In the EUH-NT trial sweat losses were fully replaced via the NG tube. Following the 2 hours of steady state, the cyclists completed a 5-kilometer cycling time trial at 4% grade. Study 2: Eleven male cyclists (weight 75.8±6.4 kg, VO2peak: 64.9±5.6 mL·kg·min-1, body fat: 12.0±5.8%) performed three sets of criterium-like cycling, consisting of 20 min of steady state cycling at 50% peak power output, each followed by a 5-km time-trial at 3% grade. Subjects completed the protocol on two separate occasions either hypohydrated (HYP) or euhydrated (EUH). In both trials, subjects ingested 25 mL every 5 min during the steady-state and 25 mL every 1-km during the 5-km time-trials. In the EUH trial, sweat losses were fully replaced via intravenous infusion of isotonic saline while in the DEH trial, a sham IV was instrumented. Results: In Study 1, cyclists completed the 5-km time trial faster in the EUH-NT trial compared to the DEH-NT trial (23.2±0.2 vs. 22.3±0.3 km·h-1, P\u3c0.05), while producing higher power output (295±29 vs. 270±26 W, P\u3c0.05). In Study 2, during the second and third time-trials, subjects displayed faster speed in the EUH trial (27.5±3.0 and 27.2±3.1 km·h-1) compared to the HYP trial (26.2±2.9 and 25.5±3.3 km·h-1; both P\u3c0.05). Core temperature (Tre) was also higher in the HYP trial throughout the third steady-state (P\u3c0.05) and continued to be higher throughout the third 5-km time-trial (P\u3c0.05). Conclusions: These data suggest that full fluid replacement, even in a blinded manner, provided a performance advantage by maintaining better hydration state. This benefit seems to be associated with the lower thermoregulatory strain, due to lower core temperatures