Evaluation of a Headspace Solid‐Phase Microextraction Method for the Analysis of Ignitable Liquids in Fire Debris

The chemical analysis of fire debris represents a crucial part in fire investigations to determine the cause of a fire. A headspace solid‐phase microextraction (HS‐SPME) procedure for the detection of ignitable liquids in fire debris using a fiber coated with a mixture of three different sorbent materials (Divinylbenzene/Carboxen/Polydimethylsiloxane, DVB/CAR/PDMS) is described. Gasoline and diesel fuel were spiked upon a preburnt matrix (wood charcoal), extracted and concentrated with HS‐SPME and then analyzed with gas chromatography/mass spectrometry (GC/MS). The experimental conditions—extraction temperature, incubation and exposure time—were optimized. To assess the applicability of the method, fire debris samples were prepared in the smoke density chamber (SDC) and a controlled‐atmosphere cone calorimeter. The developed methods were successfully applied to burnt particleboard and carpet samples. The results demonstrate that the procedure that has been developed here is suitable for detecting these ignitable liquids in highly burnt debris.     

The influence of interest: Real US interest rates and bilateral investment treaties

Bilateral Investment Treaties (BITs) present developing countries with a trade-off. BITs plausibly increase access to international capital in the form of foreign direct investment (FDI), but at the cost of substantially curtailing a government’s policy autonomy. Nearly 3000 BITs have been entered into, suggesting that many countries have found this trade-off acceptable. But governments’ enthusiasm for signing and ratifying BITs has varied considerably across countries and across time. Why are BITs more popular in some places and times than others? We argue that capital scarcity is an important driver of BIT signings: The trade-off inherent in BITs becomes more attractive to governments as the need to secure access to international capital increases. More specifically, we argue that the coincidence of high US interest rates and net external financial liabilities heightens governments’ incentives to secure access to foreign capital, and therefore results in BIT signings. Empirical evidence is consistent with our theory.     

The long road home: migratory experience and the construction of the self

Using autobiographical narratives, this article explores the experience and role of childhood immigration in the ongoing construction of self-identity. A variety of border-crossings are considered in the child's journey from cultural marginalization to acculturation into American society. Continuing feelings of displacement and loss into adulthood-common tropes in adult narratives-are then examined, as are immigrants' efforts to creatively address aspects of a hybrid identity, e.g., via "return trips" to the homeland or through the deployment of a double vision in the interest of social and political inclusiveness.     

Rich in tradition

<正>Islam’s presence in China still manifests itself today the Tongxin Great Mosque in Wuzhong—about two hours’drive south of yinchuan,the capital of northwest China’s Ningxia Hui Autonomous Region—is a pearl of wellpreserved Islamic culture in China.Built in the 14th century,the mosque is one of the oldest Muslim places of worship