Touchdown of the Hayabusa Spacecraft at the Muses Sea on Itokawa

After global observations of asteroid 25143 Itokawa by the Hayabusa spacecraft, we selected the smooth terrain of the Muses Sea for two touchdowns carried out on 19 and 25 November 2005 UTC for the first asteroid sample collection with an impact sampling mechanism. Here, we report initial findings about geological features, surface condition, regolith grain size, compositional variation, and constraints on the physical properties of this site by using both scientific and housekeeping data during the descent sequence of the first touchdown. Close-up images revealed the first touchdown site as a regolith field densely filled with size-sorted, millimeter- to centimeter-sized grains.

Evaluation of intrapleural analgesia in the management of blunt traumatic chest wall pain: a clinical trial

Intrapleural analgesia (IPA) has been successfully used for the relief of chest wall pain. Previous studies investigating its use have yielded conflicting results and have often suffered from design defects. The theoretical lower incidence of respiratory and circulatory depression with IPA suggests significant advantages over epidural analgesia. Patients who had documented blunt chest wall trauma were entered into a prospective, randomized, double-blinded, crossover, placebo-controlled study within 16 hours of their injury. Patients who were intubated or had significant trauma outside of the chest wall were not entered. Intrapleural catheters were placed using a standardized technique. Each patient received either a placebo solution of normal saline or a combination of bupivacaine/lidocaine in a blinded, crossover fashion for two 24-hour periods. Data were obtained on the use of supplementary narcotics, transcutaneous pCO(2') pulse oximetry, pulmonary function tests, and both patient and nursing evaluations of pain based on a numeric analogue scale. A series of 16 patients from a Level I trauma center were identified over a 2-year period. The ratio of male to female was approximately 2:1, with an age range of 35-80 years. There were no complications related to catheter placement or anesthetic toxicity. Mean values for patient and nursing pain ratings revealed opposite trends. We found no significant difference in the mean values for supplemental narcotic use, pCO(2') p0(2') forced vital capacity, or forced expiratory volume between the placebo and the test solution. Although previous studies have suggested that IPA may be beneficial in the management of chest wall pain, this was not confirmed in our study for blunt chest injuries. The addition of IPA to the more traditional use of opioid analgesics was not more effective for management of blunt chest wall pain. Despite our small patient population (n = 16), the crossover design should have allowed clinically significant differences to become evident (alpha value = 0.95). A review of the literature and a historical basis for the evolution in the management of this type of pain is included.

Endoscopic stent configuration and bile flow rates in a variable diameter bile duct model

Endoscopically placed biliary stents are used in the treatment of biliary strictures and obstruction. Patency of the stent is related to bile flow rate through the stent. The purpose of this study was to examine the influence of stent diameter, configuration, and common duct diameter on bile flow rates. Flow rates were examined in straight and pigtail stents, 7 Fr and 10 Fr, and in a 1 cm and 2.3 cm diameter CBD model. Bile-flow rates were greater in the straight and 10 Fr stents. Bile-duct diameter had no influence on flow rate in pigtail stents. Though flow rates decreased with straight stents in bile ducts of increasing diameter, the absolute flow rates always remained greater in the straight stents when compared to the pigtail stents. We conclude that straight stents, because of greater flow rates, are to be preferred over pigtail stents for the treatment of biliary obstruction in dilated and nondilated systems.