Sub-surface characterisation of latest-generation identification documents using optical coherence tomography

The identification of individuals, particularly at international border crossings, coupled with the evolving sophistication of identity documents are issues that authorities must contend with. Particularly, the ability to distinguish legitimate from counterfeit documents, with high throughput, sensitivity, and selectivity is an ever-evolving challenge.Over the last decade, an increasing number of security features have been introduced by authorities in identification documents. The latest generation of travel documents (such as passports and national ID cards) forego paper substrates for several layers of polycarbonate, allowing security features to be embedded within the documents. These security features may contain information at either the superficial and sub-surface levels, thus increasing the document’s resilience to counterfeiting.As the documents become harder to forge, so does the sophistication of forgery detection. There appears to be an unmet and evolving need to identify such sophisticated forgeries, in a non-destructive, high throughput manner.In this publication, we report on the application of optical coherence tomography (OCT) imaging on assessing security features in specimen passports and national ID cards. OCT allows sub-surface imaging of translucent structures, non-destructively enabling quantitative visualisation of embedded security features.     

脑认知神经测谎技术及应用性述评

本文主要回顾了当前主要的几种脑认知成像技术以及其在测谎中的尝试,介绍了这些成像技术的研究成果,并对这些测谎技术的应用性及所面临的问题等做出讨论。     

The Social Construction of Policy Reform: Economists and Trade Liberalization Around the World

We argue that the global spread of ideas contributes to trade liberalization. Building on insights from a rich case-based literature, we suggest an explicit mechanism of trade policy diffusion: US-trained Ph.D. economists, who share a common belief in the benefits of free trade, and who operate with varying degrees of political influence around the world. We offer the first cross-national test of the impact of economists on trade liberalization using a unique dataset recording the country of residence of all 6,493 foreign-based, US-trained American Economic Association (AEA) members over the period 1981–1997. Specifically, we measure the influence of economists on the timing and extent of trade liberalization. First, we endogenize the date of trade liberalization using hazard and probit models. Controlling for alternative diffusion mechanisms and other confounding variables, our results suggest that economists significantly speed up the reform process. Second, we find that countries with greater numbers of economists are more open to trade at the end of the period. All of our results are robust to an instrumental variables strategy that employs the number of Fulbright grants allocated by the United States as an instrument for the number of US-trained economists.     

BOLD—fMRI在肇事肇祸精神分裂症研究中综述

综述了肇事肇祸精神病患者脑功能异常区以及异常区之间的相互关系。主要采用事件相关的图片线索诱导一中性线索反应模式的fMRI扫描，对司法鉴定为精神病患者进行的探索实验性研究。结果表明，双侧大脑额叶、颞叶区域存在多个脑功能激活区。因此，脑功能成像（fMRI）可以作为肇事肇祸精神病司法鉴定的一个有效手段。     

MRI鉴别新鲜与陈旧性椎体压缩性骨折

目的 探讨MRI对新鲜与陈旧性椎体压缩性骨折的鉴别价值.方法 回顾性分析43例胸、腰椎椎体压缩性骨折的MRI表现,MRI检查序列主要为T1WI、T2WI和STIR.结果 本组43例共发现55处胸、腰椎椎体压缩性骨折,其中46处椎体被判定为新鲜骨折,T1WI呈低信号或低信号中混有少许高信号,T2WI呈高信号,STIR呈明...     

Body scanners versus privacy and data protection

In recent history, the world has experienced dramatic events which have had a substantial effect on the balance between human rights protection and security measures. Body scanners installed at airports are intended to protect our lives. But at the same time they have a serious impact on privacy and data protection. The international legislation allows limiting people’s rights and freedoms, but only if it is in accordance with the law and is proportionate and necessary for national security, public safety and for the protection of the rights and freedoms of others. Do body scanners respect these principles? The article examines the current situation, its background and future prospects. It discusses and analyzes the key terms and legal instruments, problems, disputes and proposed “safeguards”. The work concludes by pointing out the unlawfulness of current regimes and sets forth perspective on the possible solutions.     

Investigation into the merits of infrared imaging in the investigation of tattoos postmortem

Infrared imaging has a history of use in the forensic examination of artwork and documents and is investigated here for its wider use in the detection of tattoos on the human body postmortem. Infrared photographic and reflectographic techniques were tested on 18 living individuals, displaying a total of 30 tattoos. It was observed that neither age, sex, age of the tattoo, nor, most significantly, skin color affected the ability to image the tattoos using infrared imaging techniques. Second, a piglet carcass was tattooed and the impact of the decomposition process on the visibility of the tattoos assessed. Changes were recorded for 17 days and decomposition included partial mummification and skin discoloration. Crucially, the discoloration was recorded as greatly affecting the image quality using conventional photography, but was insignificant to the infrared recording of these tattoos. It was concluded that infrared reflectography was beneficial in the investigation into tattoos postmortem.     

PryJector: a device for in situ visualization of chemical and physical property distributions on surfaces using projection and hyperspectral imaging

Traditional forensic methods that highlight the spatial distribution of properties such as blood and fingerprints have two main disadvantages: they often apply chemicals that may influence further analyses, and they cannot easily be modified to search for new compounds/properties. A new instrument (called PryJector) avoids these problems by dynamically projecting back onto the surface under study spatially distributed information of compounds/properties (chemical images) obtained from multivariate analysis of hyperspectral images. Selectivity to target compounds/properties is ensured by multivariate modeling which makes the instrument much more flexible compared to traditional methods. The functionality of the PryJector is demonstrated in an application related to the detection of counterfeit pharmaceuticals where compounds otherwise indistinguishable to the human eye are made clearly visible by projection of false-colored chemical images. The PryJector is shown to be a noninvasive and very flexible instrument for highlighting spatial distributions of various compounds/properties.     

In vivo facial tissue depth study of Chinese-American adults in New York City

This study examines facial tissue depth in adult Chinese-Americans. Using ultrasound, measurements were taken at 19 landmarks across the faces of 101 individuals aged from 18 to 87 years. Summary statistics are reported for a sample of 67 individuals of normal weight (as determined by a body mass index [BMI] of 19-25). Statistical analyses were used to assess relationships between tissue thickness, age, and BMI. Results indicate that no significant relationship exists between tissue thickness and age for males, and for only 3/19 points in females. Also, only four points showed significant relationships between tissue thickness and sex. However, significant relationships exist between BMI and tissue thickness at multiple points for both males and females. Compared to other American and Asian populations in the literature, Chinese-Americans generally had thinner facial tissue; though, this difference was not assessed statistically. Finally, data generated in this study will add to the body of knowledge concerning facial tissue depth variation in modern humans.     

Fatal paradoxical air embolism diagnosed by postmortem imaging and autopsy

The recognition and visualization of an arterial gas embolism are difficult. We report a case of sudden death caused by paradoxical air embolism of coronary and cerebral arteries, diagnosed by the pre autopsy computed tomography (CT) scanning. A 54-year-old woman suddenly died after the self-removal of the jugular vein catheter. Postmortem imaging examination using CT scanning showed multiple gas embolisms in the cerebral arteries, pulmonary artery, right atrium and ventricle, left ventricle, aorta, and coronary arteries. These findings suggested that the occurrence of acute ischemia of the brain and heart caused by massive air inflow to the artery. Conventional autopsy revealed a patent foramen ovale of the heart. These results indicated that the patient died of paradoxical air embolization of the coronary and cerebral arteries through a patent foramen ovale because of right-to-left shunting. The use of postmortem imaging as an aid for conventional autopsy has proved to be of advantage in the case of gas embolism.