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In view of the feed/foods inevitably contaminated by toxic and carcinogenic aflatoxin B1 (AFB1), efficient mesoporous metformin-chitosan/silica­cobalt ferrite nanospheres (Mt-CS/CFS NSs) was prepared to remove AFB1 from aqueous/non-aqueous media. The morphological, functional, and structural characteristics and adsorption properties of C/N-enriched CS/CFS were investigated systematically. The interactive operating variables (temperature (5.0-35 °C); time (10-100 min); AFB1 dose (50-100 µg/mL); and Mt-CS/CFS dosage (0.5-3.5 mg) were optimized via the Box-Behnken design (BBD), which demonstrated good agreement between the experimental data and proposed model. The adsorption efficiency in artificially contaminated cow's milk as well as aqueous environment reached over 91.0 % in a wide pH range (3.0-9.0), without significant change in the nutritional value of milk. Freundlich isotherm and second-order adsorption kinetics were regarded as the most suitable models to fit the adsorption results, and the adsorption rate is dominated by the intra-particle diffusion and boundary layer diffusion. Thermodynamic analyses proved that the process was spontaneous and exothermic. The adsorption mechanism could be explained as physisorption via hydrogen bonding, n-π interaction, and hydrophobic/hydrophilic interactions. The porous Mt-CS/CFS NS derived from chitosan nanoparticles is therefore outstanding adsorbent, offering great adsorptive performance and recycabilities, which impedes economic losses in the food industry.

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BACKGROUND: Considering the limited available resources, high cost of the helicopter emergency medical service (HEMS), and high load of trauma patients especially in our centers, a careful assessment of HEMS in our center seemed to be necessary for trauma patients. METHODS: From April 2001 to September 2007, the data of all patients transferred by HEMS were extracted including: Annual number of services, clinical category, number of proper or improper services, and rescue time for HEMS and ground ambulance. The criteria for the properly transferred group included: Death or being operated in the first 24 hours of admission, admission in ICU care units, and transfer of more than three patients in one mission. Others were considered as improper group. RESULTS: In this period through 185 flights, 225 victims were transferred. The most common reason of HEMS dispatching was trauma. The most difference of rescue time between ground ambulance and HEMS was recorded in Lamerd that was transferring patients with HEMS needed 3 hours less than ground ambulance. However, in Sarvestan, Dashte-Arjan, and Marvdasht, transferred patients with ground ambulance needed less time than air transfer. Most of transferred patients were from Kazeroon, Nourabad and Lamerd respectively while 46.3% of patients were in the proper group, and the rest were considered as improper group. CONCLUSION: Our study revealed that helicopter dispatch to the cities like Lamerd, Lar, Khonj, Abadeh can be more effective, whereas, for the towns like Marvdasht, Dashte-Arjan, Sarvestan, Sepidan, Saadatshar, Tang Abolhayat use of HEMS should be limited to specific conditions. Our study showed inclusion of physicians in the decision making team increased the number of transferred cases.

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