Purification of biomimetic apatite-based hybrid colloids intended for biomedical applications: a dialysis study

The field of nanobiotechnology has lately attracted much attention both from therapeutic and diagnosis viewpoints. Of particular relevance is the development of colloidal formulations of biocompatible nanoparticles capable of interacting with selected cells or tissues. In this context, the purification of such nanoparticle suspensions appears as a critical step as residues of unreacted species may jeopardize biological and medical outcomes, and sample purity is thus increasingly taken into account by regulatory committees. In the present work, we have investigated from a physico-chemical point of view the purification by dialysis of recently developed hybrid colloids based on biomimetic nanocrystalline apatites intended for interacting with cells. Both Eu-doped (2 mol.% relative to Ca) and Eu-free suspensions were studied. The follow-up of the dialysis process was carried out by way of FTIR, TEM, XRD, pH and conductivity measurements. Mathematical modelling of conductivity data was reported. The effects of a change in temperature (25 and 45 ◦C), dialysis medium, and starting colloid composition were evaluated and discussed. We show that the dialysis method is a well-adapted and cheap technique to purify such mineral–organic hybrid suspensions in view of biomedical applications, and we point out some of the characterization techniques that may prove helpful for following the evolution of the purification process with time

Variation in annual volume at a university hospital does not predict mortality for pancreatic resections.

Annual volume of pancreatic resections has been shown to affect mortality rates, prompting recommendations to regionalize these procedures to high-volume hospitals. Implementation has been difficult, given the paucity of high-volume centers and the logistical hardships facing patients. Some studies have shown that low-volume hospitals achieve good outcomes as well, suggesting that other factors are involved. We sought to determine whether variations in annual volume affected patient outcomes in 511 patients who underwent pancreatic resections at the University of California, San Francisco between 1990 and 2005. We compared postoperative mortality and complication rates between low, medium, or high volume years, designated by the number of resections performed, adjusting for patient characteristics. Postoperative mortality rates did not differ between high volume years and medium/low volume years. As annual hospital volume of pancreatic resections may not predict outcome, identification of actual predictive factors may allow low-volume centers to achieve excellent outcomes

Building distributed heterogeneous smart phone Java applications an evaluation from a development perspective

The advances in mobile phone technology have enabled such devices to be programmed to run general-purpose applications using a special edition of the Java programming language. Java is designed to be a heterogeneous programming language targeting different platforms. Such ability when coupled with the provision of high-speed mobile Internet access would open the door for a new breed of distributed mobile applications. This paper explores the capabilities and limitations of this technology and addresses the considerations that must be taken when designing and developing such distributed applications. Our findings are verified by building a test client-server system where the clients in this system are mobile phones behaving as active processing elements not just mere service requesters

GCC Missile Defense: Obstacles on the Road to Integration

The U.S.-led effort to establish a missile defense architecture for the Persian Gulf has been slower and less successful than the United States had hoped, mainly due to an unwillingness and inability to cooperate among the Gulf Security Council nations whose nations the system is designed to defend. Given, inter alia, Iran’s growing ballistic missile arsenal and unease with the Joint Comprehensive Plan of Action in Gulf Arab capitals, security reassurances to the Gulf monarchies will become simultaneously more important and more difficult to make credible. In this environment, missile defense will be an important, but by no means sufficient, mechanism for assuring the Arab Gulf states. Cooperation on missile defense with the Gulf monarchies should continue, but with a realistic understanding of what is possible given the current chaos and political dynamics of the region

Future Challenges for Israel’s Iron Dome Rocket Defenses

After Hezbollah fired thousands of rockets at northern Israel during the 2006 Israel-Hezbollah War, the Israeli government began a crash program to find a technological solution to the rocket threat. The result was Iron Dome, which shot down its first rocket on April 7, 2011, and saw large-scale combat during wars in 2012 and 2014. The system has been hailed in Israel and worldwide as a success, with the Israeli military claiming a 90 percent interception rate. Some American defense commentators have even touted Iron Dome as evidence in favor of ballistic missile defense. However, serious questions remain about Iron Dome’s true technical efficacy, both in terms of its past performance and how it is likely to perform in the future under different conditions. Because so much about Iron Dome is classified, information provided by the Israeli military cannot be independently verified. Analyses performed by outside experts—both those questioning Iron Dome’s efficacy and those defending the Israeli government’s claims—are inconclusive. Assuming for the sake of argument that Iron Dome did, in fact, perform as advertised during its previous engagements, it is far from certain that it will be as successful in future engagements, where the volume of rocket fire will be higher and the rockets more accurate. This paper argues that Israel may have already reached “peak Iron Dome,” and the system’s military and political benefits will decrease in future wars until another technological breakthrough is made on rocket defense. This is not to say that Iron Dome was not worth the cost and should not have been procured. But expectations about Iron Dome from the Israeli military, Israeli civilians, and interested parties abroad should be tempered. If they are not, Iron Dome’s decreased success rate in future wars may pose political problems for Israel domestically and give Israel’s adversaries a decisive propaganda victory