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1.
Electronic control devices (ECDs) deliver high‐voltage, low‐current energy pulses temporarily paralyzing a person. For the ECD–human interaction, we have developed a computer model using the SEMCAD program within which to simulate the electrical effects throughout the body resulting from the imposition of an ECD pulse at a particular point on the body surface. Our human body models were based on cross‐sectional MRIs and CT scans, with the dielectric properties of the various tissues assigned based on previously published values. We simulated the application of a single ECD pulse and calculated the resulting electric field strength and current and charge densities at different body locations. The results were compared with corresponding values obtained by other researchers in similar simulations. Furthermore, we simulated an application of a pulse of 20‐millisecond duration equal to the European household current of 50 Hz and to the ventricular fibrillation threshold. The resulting current level indicated at the heart muscle was 1/5 the level considered the threshold for triggering ventricular fibrillation.  相似文献   

2.
Abstract: Electronic control devices (including the Advanced TASER® X26 model produced by TASER International) incapacitate individuals by causing muscle contractions. To provide information relevant to development of future potential devices, effects of monophasic square waves with different parameters were compared with those of the X26 electronic control device, using two animal models (frogs and swine). Pulse power, electrical pulse charge, pulse duration, and pulse repetition frequency affected muscle contraction. There was no difference in the charge required, between the square waveform and the X26 waveform, to cause approximately the same muscle‐contraction response (in terms of the strength‐duration curve). Thus, on the basis of these initial studies, the detailed shape of a waveform may not be important in terms of generating electro‐muscular incapacitation. More detailed studies, however, may be required to thoroughly test all potential waveforms to be considered for future use in ECDs.  相似文献   

3.
Abstract: Conducted energy weapons (CEWs) are used by law‐enforcement personnel to incapacitate individuals quickly and effectively, without causing lethality. CEWs have been deployed for relatively long or repeated exposures during law‐enforcement operations. The purpose of this technical note is to describe, in detail, some aspects of an anesthetized swine model used in our laboratory and to answer specific questions related to the model. In particular, tiletamine/zolazepam‐induced, propofol‐maintained anesthesia appears to be a useful technique for studying effects of CEW applications on muscle contraction and blood factors such as muscle enzymes. Because effects of CEWs on breathing have not been fully elucidated, a spontaneously breathing model is preferable to one in which mechanical ventilation is supplied. Placement of the swine in a supine position may facilitate measurement of muscle contractions, without compromising other physiological parameters.  相似文献   

4.
Conducted energy weapons (CEWs) are used by law enforcement personnel to incapacitate individuals quickly and effectively, without intending to cause lethality. CEWs have been deployed for relatively long or repeated exposures in some cases. In laboratory animal models, central venous hematocrit has increased significantly after CEW exposure. Even limited applications (e.g., three 5-sec applications) resulted in statistically significant increases in hematocrit. Preexposure hematocrit was significantly higher in nonsurvivors versus survivors after more extreme CEW applications. The purpose of this technical note is to address specific questions that may be generated when examining these results. Comparisons among results of CEW applications, other electrical muscle stimulation, and exercise/voluntary muscle contraction are included. The anesthetized swine appears to be an acceptable animal model for studying changes in hematocrit and associated red blood cell changes. Potential detrimental effects of increased hematocrit, and considerations during law enforcement use, are discussed.  相似文献   

5.
Abstract: Conducted energy weapons (such as the Advanced TASER X26 model produced by TASER International), incapacitate individuals by causing muscle contractions. To provide information relevant to development of future potential devices, a “Modifiable Electronic Stimulator” was used to evaluate the effects of changing various parameters of the stimulating pulse. Muscle contraction was affected by pulse power, net/gross charge, pulse duration, and pulse repetition frequency. The contraction force increased linearly as each of these factors was increased. Elimination of a precursor pulse from X26‐like pulses did not have a significant effect on the normalized force measured. Muscle‐contraction force increased as the spacing increased from 5 to 20 cm, with no further change in force above 20 cm of spacing. Therefore, it is suggested that any future developments of new conducted energy weapons should include placement of electrodes a minimum of 20 cm apart so that efficiency of the system is not degraded. In the current study, the 50% probability of fibrillation level of X26‐like pulses ranged from 4 to 5 times higher than the X26 itself. Relatively large variations about the X26 operating level were found not to result in fibrillation or asystole. Therefore, it should be possible to design and build an X26‐type device that operates efficiently at levels higher than the X26.  相似文献   

6.
As the result of the communist terror in Poland, during years 1944–1956 more than 50,000 people died. Their bodies were buried secretly, and most places are still unknown. The research presents the results of identification of people buried in one of many mass graves, which were found at the cemetery Pow?zki Military in Warsaw, Poland. Exhumation revealed the remains of eight people, among which seven were identified genetically. Well‐preserved molars were used for the study. Reference material was collected from the closest living relatives. In one case, an exhumation of victim's parents had to be performed. DNA from swabs was extracted with a PrepFiler® BTA Forensic DNA Extraction Kit and organic method. Autosomal, Y‐STR amplification, and mtDNA sequencing were performed. The biostatistical calculations resulted in LR values from 1608 to 928 × 1018. So far, remains of more than 50 victims were identified.  相似文献   

7.
In laboratory studies of the pig Sus scrofa, hematocrit has consistently increased after conducted‐electrical‐weapon (CEW) exposures, possibly due to contraction of the spleen. Splenectomized animals and intact sham control animals were exposed, each for 30 sec, to a benchtop‐produced electrical waveform of net charge levels similar to those of some CEWs. Changes in the blood were compared statistically. Hematocrit increased significantly in both splenectomized and sham animals. There were no significant main‐effect differences between values of hematocrit from the two groups. There were, however, significant interactive effects of time and splenectomy for hematocrit, red blood cell count, and hemoglobin. After peak values were reached for these variables, values returned toward baseline levels more slowly in splenectomized animals. This may have been due to the lack of a spleen to sequester red blood cells (thereby resulting in more cells remaining in the general circulation), unlike sham animals with intact spleens.  相似文献   

8.
The international prevalence of “legal high” drugs necessitates the development of a method for their detection and identification. Herein, we describe the development and validation of a tetraplex multiplex real‐time polymerase chain reaction (PCR) assay used to simultaneously identify morning glory, jimson weed, Hawaiian woodrose, and marijuana detected by high‐resolution melt using LCGreen Plus®. The PCR assay was evaluated based on the following: (i) specificity and selectivity—primers were tested on DNA extracted from 30 species and simulated forensic samples, (ii) sensitivity—serial dilutions of the target DNA were prepared, and (iii) reproducibility and reliability—sample replicates were tested and remelted on different days. The assay is ideal for cases in which inexpensive assays are needed to quickly detect and identify trace biological material present on drug paraphernalia that is too compromised for botanical microscopic identification and for which analysts are unfamiliar with the morphology of the emerging “legal high” species.  相似文献   

9.
A flow‐injection analysis tandem mass spectrometry (FIA MSMS) method was developed for rapid quantitative analysis of 10 different inorganic and organic explosives. Performance is optimized by tailoring the ionization method (APCI/ESI), de‐clustering potentials, and collision energies for each specific analyte. In doing so, a single instrument can be used to detect urea nitrate, potassium chlorate, 2,4,6‐trinitrotoluene, 2,4,6‐trinitrophenylmethylnitramine, triacetone triperoxide, hexamethylene triperoxide diamine, pentaerythritol tetranitrate, 1,3,5‐trinitroperhydro‐1,3,5‐triazine, nitroglycerin, and octohy‐dro‐1,3,5,7‐tetranitro‐1,3,5,7‐tetrazocine with sensitivities all in the picogram per milliliter range. In conclusion, FIA APCI/ESI MSMS is a fast (<1 min/sample), sensitive (~pg/mL LOQ), and precise (intraday RSD < 10%) method for trace explosive detection that can play an important role in criminal and attributional forensics, counterterrorism, and environmental protection areas, and has the potential to augment or replace several of the existing explosive detection methods.  相似文献   

10.
A number of N‐substituted piperazines have been described as drugs of abuse in recent years. This new drug category includes several series of aromatic ring substituted phenylpiperazines. The wide variety of available precursors makes regioisomerism a significant issue in these totally synthetic compounds. In this study, a complete series of regioisomeric dimethoxyphenylpiperazines were synthesized and evaluated using GC‐MS and FT‐IR. The EI mass spectra show fragments characteristic of both the dimethoxyphenyl and the piperazine portions of the molecules including the dimethoxyphenylaziridinium cation (m/z 180) and dimethoxyphenyl cation (m/z 137). The ion at m/z 56 for the C3H6N+ fragment is characteristic of the piperazine ring and was observed in all the spectra. The perfluoroacyl derivatives were resolved by GC, and their mass spectra showed some differences in relative abundance of ions. FTIR provides direct confirmatory data for differentiation between the regioisomeric dimethoxyphenylpiperazines, and GC separation was accomplished on an Rtx‐200 phase.  相似文献   

11.
Previous studies have shown a significant amount of contaminants on paper currencies. It is important to study the transfer of microorganisms between paper currencies to determine whether it meets the level of a human health threat. This cross‐contamination potential was analyzed by seeding new US 1‐dollar bills with Bacillus thuringiensis, and pressing or rubbing them against clean currency to determine the amount of bacteria transfer to the unseeded currency. The transferred amount of bacteria was recovered, plated, incubated, and the colony‐forming units were quantified. Among the recovery methods tested, the most efficient method, vortexing for 10 min with a recovery efficiency of 40 ± 8.1%, was used in this analysis. The resulting transfer rates were 4.8%, 8.6%, and 14.3% when pressed for 24 h, 72 h, and rubbed together, respectively. These transferred amounts of bacteria are significant and have the potential to spread infectious diseases.  相似文献   

12.
Phenotypic and genotypic characteristics of the cat can be obtained from single nucleotide polymorphisms (SNPs) analyses of fur. This study developed miniplexes using SNPs with high discriminating power for random‐bred domestic cats, focusing on individual and phenotypic identification. Seventy‐eight SNPs were investigated using a multiplex PCR followed by a fluorescently labeled single base extension (SBE) technique (SNaPshot®). The SNP miniplexes were evaluated for reliability, reproducibility, sensitivity, species specificity, detection limitations, and assignment accuracy. Six SNPplexes were developed containing 39 intergenic SNPs and 26 phenotypic SNPs, including a sex identification marker, ZFXY. The combined random match probability (cRMP) was 6.58 × 10?19 across all Western cat populations and the likelihood ratio was 1.52 × 1018. These SNPplexes can distinguish individual cats and their phenotypic traits, which could provide insight into crime reconstructions. A SNP database of 237 cats from 13 worldwide populations is now available for forensic applications.  相似文献   

13.
We report the case of a man who died twelve hours after ingesting powdered iboga root, commonly taken for its stimulant and hallucinogenic properties. Ibogaine and ibogamine were quantified in the powder ingested and the victim's body fluids by GC‐MS/MS after liquid–liquid extraction (Toxi‐tubes A®). The concentrations of ibogaine measured in the blood samples taken at the scene and in the peripheral blood, urine, and gastric fluid samples taken during the autopsy were 0.65, 1.27, 1.7, and 53.5 μg/mL, while the iboga content in the powder was 7.2%. Moreover, systematic toxicological analyses of biological samples showed the presence of diazepam and methadone in therapeutic concentrations. Death was attributed to the ingestion of a substantial quantity of iboga in the context of simultaneous methadone and diazepam consumption.  相似文献   

14.
From November 1, 2010 through November 30, 2012, 1204 whole‐blood samples were confirmed to contain THC alone or in combination with other drugs out of nearly 5000 Orange County, California, drivers suspected of driving under the influence of drugs. The goal of this study was to examine police reports and drug recognition expert evaluations of THC‐positive samples within this 2‐year time frame to determine whether there is a correlation between whole‐blood THC concentrations and field sobriety tests performance on DRE and non‐DRE evaluations. The FSTs prove to be sensitive to impairment by marijuana although as suspected, the findings of this study did not find a correlation between performance on field sobriety tests and the concentration of THC tested in whole‐blood samples. Driving behaviors were also examined and found to be similar to those seen in alcohol impairment. Future studies examining DRE findings are needed to confirm the results.  相似文献   

15.
The case of a 22‐year‐old male Caucasian driver is presented. He was involved in a traffic collision. At the roadside, he displayed blank stare and mellow speech with a barely audible voice. A DRE found low body temperature, rigid muscle tone, normal pulse, lack of horizontal and vertical gaze nystagmus, nonconvergence of the eyes, dilated pupil size, and normal Pupillary reaction to light. A standard toxicology DUID protocol was performed on the driver's whole blood including ELISA and GC‐MS drug screens with negative results. Additional drug screening was undertaken for bath salts and synthetic cannabinoid receptor agonists by LC‐MS/MS by a commercial laboratory and identified the synthetic cannabinoid receptor agonist XLR‐11 in the driver's blood. XLR‐11 was subsequently quantified at 1.34 ng/mL. This is the first documented case involving a driver operating a motor vehicle under the influence of the synthetic cannabinoid receptor agonist XLR‐11.  相似文献   

16.
A bead‐based liquid hybridization assay, Luminex® 100?, was used to identify four pathogenic bacteria, Bacillus anthracis, Clostridium botulinum, Francisella tularensis subsp. tularensis, and Yersinia pestis, and several close relatives. Hybridization between PCR‐amplified target sequences and probe sequences (located within the 23S ribosomal RNA gene rrl and the genes related to the toxicity of each bacterium) was detected in single‐probe or multiple‐probe assays, depending on the organism. The lower limits of detection (LLDs) for the probes ranged from 0.1 to 10 ng. Sensitivity was improved using lambda exonuclease to digest the noncomplementary target strand. All contributors in 33 binary, ternary, and quaternary mixtures in which all components were present in a 1:1 ratio were identified with an 80% success rate. Twenty‐eight binary mixtures in which the two components were combined in various ratios were further studied. All target sequences were detected, even when the minor component was overshadowed by a tenfold excess of the major component.  相似文献   

17.
This study investigated the influence of paraquat, a prevalent poison used by suicides, on initial oviposition and development of Chrysomya megacephala (Fabricius) using minced‐beef substrates. Paraquat in lethal dose for human (40 mg/kg), two times the lethal dose (80 mg/kg) and five times the lethal dose (200 mg/kg) were mixed thoroughly with respective minced‐beef substrates (1 kg each) that were decomposed in a shaded habitat fully protected from rain. Results of four replications of the above experiment revealed that the presence of paraquat neither delayed initial oviposition nor prolonged the developmental stages of C. megacephala. Therefore, estimation of postmortem interval (PMI) based on empirical baseline data obtained using animal models devoid of any poisons would still be appropriate for estimating PMI in paraquat‐related deaths.  相似文献   

18.
Alcohol‐related amnesia—alcohol blackout—is a common claim of criminal defendants. The generally held belief is that during an alcohol blackout, other cognitive functioning is severely impaired or absent. The presentation of alcohol blackout as scientific evidence in court requires that the science meets legal reliability standards (Frye, FRE702/Daubert). To determine whether “alcohol blackout” meets these standards, an evidence‐based analysis of published scientific studies was conducted. A total of 26 empirical studies were identified including nine in which an alcohol blackout was induced and directly observed. No objective or scientific method to verify the presence of an alcoholic blackout while it is occurring or to confirm its presence retrospectively was identified. Only short‐term memory is impaired and other cognitive functions—planning, attention, and social skills—are not impaired. Alcoholic blackouts would not appear to meet standards for scientific evidence and should not be admissible.  相似文献   

19.
Psilocybe cubensis, or “magic mushroom,” is the most common species of fungus with psychedelic characteristics. Two primer sets were designed to target Psilocybe DNA using web‐based software and NBCI gene sequences. DNA was extracted from eighteen samples, including twelve mushroom species, using the Qiagen DNeasy® Plant Mini Kit. The DNA was amplified by the polymerase chain reaction (PCR) using the primers and a master mix containing either a SYBR® Green I, Radiant? Green, or LCGreen Plus® intercalating dye; amplicon size was determined using agarose gel electrophoresis. The PCR assays were tested for amplifiability, specificity, reproducibility, robustness, sensitivity, and multiplexing with primers that target marijuana. The observed high resolution melt (HRM) temperatures for primer sets 1 and 7 were 78.85 ± 0.31°C and 73.22 ± 0.61°C, respectively, using SYBR® Green I dye and 81.67 ± 0.06°C and 76.04 ± 0.11°C, respectively, using Radiant? Green dye.  相似文献   

20.
《Justice Quarterly》2012,29(4):598-625
In a recent paper, researchers reported increases in the risk of citizen injury associated with police use of conducted energy devices (CEWs), a finding that is contrary to that reported in most previous studies. These authors speculate that the differences in findings when compared to other similar studies may be due, in part, to the exclusion of routine CEW dart punctures as injuries by other researchers, and they called on the research community to collectively agree on how CEW injuries should be operationalized. In this paper, we empirically demonstrate the differences in findings when routine CEW puncture wounds are included as citizen injuries and when they are not. Ultimately, we reject the authors’ measurement approach as inconsistent with how injuries associated with other types of force are routinely coded and measured.  相似文献   

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