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151.
Telecommunications regulation has experienced a fundamentalshift from rate regulation to increased reliance on compelledaccess, perhaps best exemplified by the Telecommunications Actof 1996's imposition of no fewer than four new access requirements.Unfortunately, each access requirement is governed by a separateset of rules for determining both the scope and the price ofaccess. The resulting ad hoc regime has created difficult definitionalproblems and opportunities for regulatory arbitrage. In thisarticle we propose a system inspired by the discipline of mathematicsknown as graph theory that integrates all of the different formsof access into a single analytical framework. This system separatesdifferent access regimes into five categories: (1) retail access,(2) wholesale access, (3) interconnection access, (4) platformaccess, and (5) unbundled access. It also provides insightsinto how each type of access complicates the already difficultproblems of network configuration and management and introducesinefficient biases into decisions about network capacity anddesign. The approach we propose also provides insights intothe transaction cost implications of the different types ofaccess. Drawing on the Coasean theory of the firm, our approachexamines the tradeoffs between internal governance costs andthe external transaction costs of providing access to offera theory of network boundaries. This framework shows how accessregulation distorts networks' natural boundaries and providesa basis for evaluating whether private ordering through marketswould lead to more efficient network design. 相似文献
152.
153.
A study was performed to acquire urine, serum and oral fluid samples in cases of suspected driving under the influence of drugs of abuse. Oral fluid was collected using a novel sampling/testing device (Dr?ger DrugTest System). The aim of the study was to evaluate oral fluid and urine as a predictor of blood samples positive for drugs and impairment symptoms. Analysis for cannabinoids, amphetamine and its derivatives, opiates and cocaine was performed in urine using the Mahsan Kombi/DOA4-test, in serum using immunoassay and gas chromatography-mass spectrometry (GC-MS) confirmation and in oral fluid by GC-MS. Police and medical officer observations of impairment symptoms were rated and evaluated using a threshold value for the classification of driving inability. Accuracy in correlating drug detection in oral fluid and serum were >90% for all substances and also >90% in urine and serum except for THC (71.0%). Of the cases with oral fluid positive for any drug 97.1% of corresponding serum samples were also positive for at least one drug; of drug-positive urine samples this were only 82.4%. In 119 of 146 cases, impairment symptoms above threshold were observed (81.5%). Of the cases with drugs detected in serum, 19.1% appeared not impaired which were the same with drug-positive oral fluid while more persons with drug-positive urine samples appeared uninfluenced (32.7%). The data demonstrate that oral fluid is superior to urine in correlating with serum analytical data and impairment symptoms of drivers under the influence of drugs of abuse. 相似文献
154.
A 77-year-old man was found in his flat with a shot to the right temple. In spite of hospital treatment he died from the head injury the next day. The weapon at the scene used for committing the suicide was a pistol, make Kaba Special (calibre 6.35 mm). At autopsy, the right temporal region showed a surgically treated, originally stellate gunshot entrance wound with a powder cavity. Close to this penetrating gunshot wound there were 3 parallel graze shot injuries of the scalp. The autopsy findings were consistent with the assumption that all the shots had been fired by the victim himself with suicidal intent. The injury pattern is presented and discussed in relation to the results of the technical investigation of the weapon and the findings at the scene. 相似文献
155.
Isotope ratio mass spectrometry as a tool for forensic investigation (examples from recent studies).
James F Carter Richard Sleeman Jenny C Hill Fay Idoine Emma L Titterton 《Science & justice》2005,45(3):141-149
The versatility of isotope ratio mass spectrometry is demonstrated by reference to diverse case studies. Variations in the natural isotopic composition of non-biological, organic materials are compared as a means by which samples may be associated or discriminated. These techniques may be used to augment or compliment conventional forensic methodologies. delta13C analysis was used to demonstrate that different masking tape had been recovered in two, apparently similar cases, involving the smuggling of money. Visually similar ecstasy tablets were compared by consideration of the delta13C and delta15N composition of MDMA extracted from the tablets. Although only a limited number of tablets were analysed, the isotopic similarity between two different seizures was sufficient to induce a guilty plea from a person suspected of possessing both. A combination of delta2H, delta13C, delta15N and delta18O together with GC-MS analyses were applied to small samples of seized heroin. Although GC-MS analysis indicated differences between the chemical composition of two of the heroin samples, isotopic analysis suggested similarities, which were confirmed by further delta2H, delta13C and delta18O isotopic analysis of the clingfilm in which the samples were wrapped. 相似文献
156.
The revised National Crime Victimization Survey is used to examine the effects of the victim's relationship to the offender on whether assaults are reported to the police by either the victim or by third parties. The results indicate that the offender-victim relationship affects third-party but not victim reporting. The former effect occurs in part because third parties are unlikely to witness assaults involving people in ongoing relationships, particularly couples, and in part because third parties are reluctant to report minor assaults (i.e., those assaults that involve a threat but no actual attack and no weapon). We discuss possible explanations for why no effect of relationship on victim reporting was found. 相似文献
157.
H Brown D M Cauchi J L Holden F C Allen S Cordner P Thatcher 《Forensic science international》1999,100(3):179-186
A statistical investigation of the relationship between firing range and the amount and distribution of gunshot residue (GSR), used automated image analysis (IA) to quantify GSR deposit resulting from firings into pig skin, from distances ranging between contact and 45 cm. Overall, for a Ruger .22 semi-automatic rifle using CCI solid point, high velocity ammunition, the total area of GSR deposit on the skin sections decreased in a non-linear fashion with firing range. More specifically there were significant differences in the amount of GSR deposited from shots fired at contact compared with shots fired from distances between 2.5 and 45 cm; and between shots fired from a distance of 20 cm or less, with shots fired at a distance of 30 cm or more. In addition, GSR particles were heavily concentrated in the wound tract only for contact and close range shots at 2.5 cm, while the particle distribution was more uniform between the wound tract and the skin surfaces for shots fired from distances greater than 2.5 cm. Consequently, for future scientific investigations of gunshot fatalities, once standards have been established for the weapon and ammunition type in question, image analysis quantification of GSR deposited in and around the gunshot wound may be capable of providing a reliable, statistical basis for estimating firing range. 相似文献
158.
Accidental hypothermia has been described in the forensic literature but reports of occurrence in hospitalized patients are rare. Associated anatomic lesions include acute hemorrhagic pancreatitis and characteristic acute gastric ulcers termed Wischnewski ulcers. We report here two patients with cirrhosis and ascites; one also had hepatocellular carcinoma. Portal vein thrombosis, acute hemorrhagic pancreatitis and Wischnewski ulcers were present in both. The clinical records documented hypothermia that progressed over several days. Temperature nadirs of 31.0 degrees C (87.8 degrees F) and 32.2 degrees C (90.0 degrees F) were recorded in each patient, respectively, one day before death, although each transiently reached temperatures that did not register on standard monitoring devices. This is the first report that chronicles antemortem body temperatures in hypothermic patients with Wischnewski ulcers and pancreatitis at autopsy. Also, the association of these findings with portal vein thrombosis and cirrhosis has not been previously described. We discuss this constellation of findings with regard to possible mechanistic interrelations. 相似文献
159.
A young nurse was found dead in her flat. In chemical-toxicological analysis the following femoral blood drug concentrations were determined: paroxetine 0.176 mg/l, doxepine 82.12 mg/l, desmethyldoxepine 0.34 mg/l. Additionally the drug concentrations were determined in various body fluids and organs. The results of the described fatality are discussed. For interpretation of toxicologic results in antidepressant fatalities ratios of parent drug to metabolite and postmortem drug redistribution should be taken into account. 相似文献
160.
Garofano L Pizzamiglio M Donato F Biondi F Rossetti M Budowle B 《Forensic science international》1999,105(2):131-136
A population study on two new short tandem repeat (STR) loci D2S1338 (a tetranucleotide repeat) and Penta E (a pentanucleotide repeat) was performed on 208 unrelated Italian Caucasians. The DNA was amplified by polymerase chain reaction (PCR) and separation and detection of the amplified STR fragments were carried out by use of a PE/ABD PRISM 377 DNA Sequencer 377 automated system (Applied Biosystems Division/Perkin-Elmer). Both loci meet Hardy-Weinberg expectations. There is no evidence for departures from expectations between the two loci. The combined Probability of Discrimination and Probability of Exclusion for the two STR loci are 0.999155 and 0.944925, respectively. The results demonstrate that these two regions can be useful for differentiating among individuals, particularly in concert with other STR loci. 相似文献