The Influence of the Body on the Response of the Helmeted Head during Impact

According to helmet standards, the absorption capacity of helmets is assessed through impact of a headform fitted with the helmet onto an anvil. It implies that the effect of the rest of the body on impact outputs has been assumed to be negligible. The purpose of this work was to investigate this effect. Full-body and detached-head impacts were simulated using the Finite Element (FE) method. A detailed FE model of a composite-shell helmet was developed and validated against experimental data. It was coupled with an FE model of the Hybrid III dummy. To validate the full-body impact model, a new test method was designed to drop test helmeted dummies. As a consequence of the presence of the body, the crushing distance of the helmet liner was drastically increased. This evidence indicated that the effect of the body should be included in impact absorption tests in order to provide conditions that are more realistic to real world accidents and more stringent. The solution to an analytical model proposed for helmeted headform impacts revealed that the influence of increasing the headform mass on impact outputs, particularly the liner crushing distance, is the same as the influence of the body. The added mass was calculated for various impact configurations by using a detailed FE model of the human body. Finally, an added mass of 20% together with a 9% reduction in the limit of head linear acceleration were proposed. Full-body and detached-head oblique impacts were also simulated. The results indicated that the body had a noticeable influence on head rotational acceleration. Modifying the inertia matrix of the head to include this effect in the detached-head drop tests was proposed. By using an FE model of the human head, intracranial injury predictors were also evaluated in oblique impacts considering the complete kinematics of the head

Hypervisor Integrity Measurement Assistant

An attacker who has gained access to a computer may want to upload or modify configuration files, etc., and run arbitrary programs of his choice. We can severely restrict the power of the attacker by having a white-list of approved file checksums and preventing the kernel from loading loading any file with a bad checksum. The check may be placed in the kernel, but that requires a kernel that is prepared for it. The check may also be placed in a hypervisor which intercepts and prevents the kernel from loading a bad file. We describe the implementation of and give performance results for two systems. In one the checksumming, or integrity measurement, and decision is performed by the hypervisor instead of the OS. In the other only the final integrity decision is done in the hypervisor. By moving the integrity check out from the VM kernel it becomes harder for the intruder to bypass the check. We conclude that it is technically possible to put file integrity control into the hypervisor, both for kernels without and with pre-compiled support for integrity measurement

An overview on audio steganography techniques

Steganography is a form of security technique through obscurity; the science and art of hiding the existence of a message between sender and intended recipient. Steganography has been used to hide secret messages in various types of files, including digital images, audio and video. The three most important parameters for audio steganography are imperceptibility, payload (bit rate or capacity), and robustness. Any technique which tries to improve the payload or robustness should preserve imperceptibility. The noise which is introduced due to bit modification would limit payload. This paper presents a categorization of information hiding techniques and overviews those techniques that intend to improve payload and imperceptibility

Studies on in vitro maturation of dog oocytes to improve maturation rate and development potentials

A thesis submitted to the University of Bedfordshire, in partial fulfilment of the requirements for the degree of Doctor of Philosophy in the Institute of Biomedical and Environmental Science and Technology (iBEST)In vitro maturation of dog oocytes has always been the main obstacle preventing reproductive biologist from producing canine in vitro cultured embryos. The unsuccessful oocyte maturation in canine species originates from their unique physiological and biological specifications. Ovulation of dominant follicles in bitch (6-12 in each oestrous cycle) occurs at prophase I stage of oocyte nucleus and meiotic resumption develops during 3-5 days of oviductal transition. During this PhD thesis, studies were designed in order to speculate characteristics of canine oocyte maturation in vitro in terms of maturation media components, gas composition of the incubator and hormonal requirements. Level of oxidative stress during 72h (culture period) of in vitro maturation showed that 5%O2, 5% CO2 and 90% N2 composition improves meiotic resumption and reduces degeneration rate significantly compared to 5% CO2 in air. Utilization of caffeine as a non specific phosphodiesterase inhibitor at 10mM for 12h at the beginning of the 72h culture (12+60) also improved MII maturation rate (16.9% ± 2.4; P < 0.05). Among several hormonal treatments recombinant porcine Growth Hormone (PGH) at 100ng/ml and Melatonin (MTN) at 100nM concentrations had outstanding improvement over meiotic resumption (28.9% ±10.0 and 56.2% ±8.6 respectively; P < 0.05). Attempts were made to study developmental potentials of optimally matured oocytes by parthenogenetic activation (PA) and in vitro fertilization (IVF) using chilled semen. Partial digestion of the zona pellucida prior to IVF improved the cleavage rate at 48h 6.4% ± 0.3 and resulted in production of a single 8 cell embryo. Moreover; canine follicular cells were culture in order to characterize their primary culture morphology and steroidogenic responsiveness to physiological and pharmaceutical substances. Immunolocalization of aromatase (CYP19) positive cell clumps, presumptive oestrogen producing colonies, was identified. This primary culture also maintained its steroidogenic machinery up to 96h (measured by radioimmunoassay) with a significant increase in production of estradiol and progesterone after 72h compare to the start of the culture

Experiences, characteristics, and features of developing new towns between 1898 and 1970

The decision on developing a new town is always informed by the needs and requirements of regional and national planning on the basis of political viewpoints, natural recourses, industrial facilities, and population surplus viewpoints. In different areas, new towns were built to address the emerging social, economic, and environmental problems by supporting better living, enabling urban activities, and supporting industrial expansion. Following the review of the related literature, this study compared the theories and bases for building new towns and studied the experiences of different countries as examples. The present desktop research was carried out based on a narrative review in order to develop a framework for assessing the success of new town projects in response to the underlying needs and aims. Although the survey of literature did not result in harmonized measures of success or failure of new towns, the identified critical measures assist decision-and policy-makers to adopt appropriate strategies to assure a higher rate of success for developing new towns

Don't cancel the surgery just yet! A case report of positive preoperative pregnancy test due to a soft tissue sarcoma production of ectopic beta human chorionic gonadotropin.

Soft tissue sarcomas are a rare group of mesenchymal malignancies which can range from low to high grade. These tumors have different clinical, radiographic, and histopathological characteristics. Beta human chorionic gonadotropin is a naturally secreted hormone by placental syncytiotrophoblast cells during pregnancy. On very rare occasions, sarcomas can develop the ability to ectopically produce human chorionic gonadotropin. Very few cases exist in the literature of soft tissue sarcomas expressing this hormone. We report the case of a 55-year-old female who presented with a posterior thigh soft tissue sarcoma who on the day of surgical resection was found to have an unusually elevated serum human chorionic gonadotropin. Positive immunohistochemical staining of the resected mass confirmed the sarcoma as the source of the beta human chorionic gonadotropin