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An open-loop control scheme of molecular fragmentation based on transient molecular alignment combined with single-photon ionization induced by a short-wavelength free electron laser (FEL) is demonstrated for the acetylene cation. Photoelectron spectra are recorded, complementing the ion yield measurements, to demonstrate that such control is the consequence of changes in the electronic response with molecular orientation relative to the ionizing field. We show that stable C2H2+ cations are mainly produced when the molecules are parallel or nearly parallel to the FEL polarization, while the hydrogen fragmentation channel (C2H2+ → C2H+ + H) predominates when the molecule is perpendicular to that direction, thus allowing one to distinguish between the two photochemical processes. The experimental findings are supported by state-of-the art theoretical calculations.

This study compared the effects of a low-frequency electrical stimulation (LFES; Veinoplus(®) Sport, Ad Rem Technology, Paris, France), a low-frequency electrical stimulation combined with a cooling vest (LFESCR ) and an active recovery combined with a cooling vest (ACTCR ) as recovery strategies on performance (racing time and pacing strategies), physiologic and perceptual responses between two sprint kayak simulated races, in a hot environment (∼32 wet-bulb-globe temperature). Eight elite male kayakers performed two successive 1000-m kayak time trials (TT1 and TT2), separated by a short-term recovery period, including a 30-min of the respective recovery intervention protocol, in a randomized crossover design. Racing time, power output, and stroke rate were recorded for each time trial. Blood lactate concentration, pH, core, skin and body temperatures were measured before and after both TT1 and TT2 and at mid- and post-recovery intervention. Perceptual ratings of thermal sensation were also collected. LFESCR was associated with a very likely effect in performance restoration compared with ACTCR (99/0/1%) and LFES conditions (98/0/2%). LFESCR induced a significant decrease in body temperature and thermal sensation at post-recovery intervention, which is not observed in ACTCR condition. In conclusion, the combination of LFES and wearing a cooling vest (LFESCR ) improves performance restoration between two 1000-m kayak time trials achieved by elite athletes, in the heat.

The purpose of this study was to investigate the effects of whole-body cryotherapy (WBC) on proprioceptive function, muscle force recovery following eccentric muscle contractions and tympanic temperature (T(TY) ). Thirty-six subjects were randomly assigned to a group receiving two 3-min treatments of -110 ± 3 °C or 15 ± 3 °C. Knee joint position sense (JPS), maximal voluntary isometric contraction (MVIC) of the knee extensors, force proprioception and T(TY) were recorded before, immediately after the exposure and again 15 min later. A convenience sample of 18 subjects also underwent an eccentric exercise protocol on their contralateral left leg 24 h before exposure. MVIC (left knee), peak power output (PPO) during a repeated sprint on a cycle ergometer and muscles soreness were measured pre-, 24, 48 and 72h post-treatment. WBC reduced T(TY) , by 0.3 °C, when compared with the control group (P0.001). However, JPS, MVIC or force proprioception was not affected. Similarly, WBC did not effect MVIC, PPO or muscle soreness following eccentric exercise. WBC, administered 24 h after eccentric exercise, is ineffective in alleviating muscle soreness or enhancing muscle force recovery. The results of this study also indicate no increased risk of proprioceptive-related injury following WBC.

A body with a gunshot wound to the head was discovered in a wooded area in mid September 1983 wrapped with about 20 consecutive layers of plastic garbage bags and rope. Examination of the body revealed a bullet hole in the occipital-parietal region and a peculiar decomposition of the body. Following a forensic reconstruction of our autopsy findings, microscopic studies and other ancillary factors, we concluded that the body had been frozen for about 2 and one-quarter years prior to its being dumped along a mountain road here in Rockland County. The means by which we concluded that the victim had been frozen for about 2 and one-quarter years and other important aspects of this case are fully discussed.

Skeletal remains removed from an unmarked grave in El Salvador were intensively studied by a team of forensic science experts. Even though the skull, teeth, and several major bones were missing, a positive identification was made of the missing journalist. This was contrary to reports submitted to the State Department by Salvadorian officials. All of the methods used in this investigation, which includes a new method for simultaneously assessing sex and race by discriminant function analysis that was tested by application, are fully described. The international background of this case and information regarding the cause of death is discussed.

A suspected automobile was identified in a hit-and-run death of a 40-year-old male by matching a tiny nonspecific fragment of tissue attached to the gasoline line clip of the undercarriage with an avulsed area on the hypothenar area of the palm of the hand. There was no ostensible damage to the auto and there was an absence of clothing remnants, blood, and other tissues and an absence of paint pigments on the victim or victim's clothing.

Critical studies of an intricate blunt force injury pattern in a brutal homicide led to the identification of the murder weapon. A 50-year-old male was bludgeoned to death in his apartment during a robbery allegedly engineered by his daughter. Careful measurements and overlay construction of the wounds relative to the magazine catch, lanyard ring, magazine chamber, and butt of a 32-caliber Eistegui Hermanos fibar (España) automatic pistol led to the conclusion that either the alleged weapon or one identical to it caused the fatal injuries.

Two meter readers of a local water company were found dead in an underground water meter pit. Studies revealed a decrease in oxygen and an increase in carbon dioxide in the pit as a result of aerobic microorganisms present in the pit. Such an atmosphere may be rapidly fatal to the unwary worker who frequents such an environment. It is of paramount importance that this occupational hazard be recognized so that preventative measures may be established. We propose that the term "Confined Space-Hypoxia Syndrome" be adopted to all such confined space accidents occurring in water meter pits, tanks, holds of ships, mines, underground storage bins, and so forth, resulting from oxygen-deficient atmospheres. A series of recommended preventative procedures is included.

Proposed methods for softening mummified fingers have been either unsuccessful in adequately softening the fingers or have been highly destructive. A simple technique based on an entirely new concept utilizing disodium ethylenediamine tetraacetic acid in a detergent solution adjusted to a pH of 7.5 has been successfully used to obtain satisfactory to good fingerprints over the past ten years in every case attempted.

A skeletonized body, wearing a black leather bondage mask, was found in a Revolutionary War smokehouse cave with two bullet holes in the back of the head. The body was skeletonized up to the maxillary area but the head region under the mask was well preserved and permitted a positive visual identification. There was evidence that the body had been eaten by small animals and subsequently burned. Investigations into this brutal murder revealed a tale of a bizarre sadomasochistic ritual that attained national prominence.

Attempts to determine the instrument in the brutal killing of a middle-aged male resulted in the positive identification of an auto jack column as the actual instrument used. This was accomplished by the use of three modalities: (1) the edge of the jack column conformed exactly to a multi-curved laceration in the forehead (site of lethal injury), (2) blood found within this edge of the jack column afforded the same blood type as that of the victim, and (3) tissue sections made of the blood and debris from this edge of the jack column revealed tissue fragments containing human keratin (antihuman keratin technique) and positive staining with collagen stains.