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This study was carried out to better understand the epidemiology of hantaviruses in a province of Turkey (Giresun) where human hantavirus disease has recently been detected. In this cross-sectional study, a total of 626 blood samples from healthy people aged 15 and 84 years old were collected both in urban and rural areas in 2009. The sera were tested by enzyme-linked immunosorbent assay (ELISA), immunoblotting assay, and the focus reduction neutralization test (FRNT). We screened the samples by an ELISA and found that 65/626 samples reacted positively for the presence of hantavirus-reactive immunoglobulin G (IgG). Twenty of the 65 ELISA-positive samples could be confirmed by an immunobloting assay, and the overall seroprevalence was thereby calculated to 3.2% (20/626). The seroprevalence of the people living in wood areas or adobe houses 9/17 (52.9%) was significantly higher than among people living in concrete houses 10/47 (21.3%) (p=0.014). Finally, 3 of the 20 immunoblot-positive sera were confirmed as specific for the Puumala hantavirus serotype by FRNT, 1 serum was confirmed as Dobrava virus-specific, whereas 1 serum was found to be equally reactive to Dobrava and Saaremaa viruses. We will now focus on further investigations of the ecology and epidemiology of hantaviruses in humans and their carrier animals in Turkey, studies that have already been started and will be further intensified.

In 2010, 47 human cases of West Nile virus (WNV)infection, including 12 laboratory-confirmed and 35 probable cases, were identified in Turkey. These were the first cases detected during routine surveillance.The patients were from 15 provinces, mainly located in the western part of the country. Incidence was 0.19/100,000 with a maximum of 1.39 in Sakarya province.Forty of the total 47 cases showed neuroinvasive manifestation. Median age was 58 years with a range of four to 86. Ten of the patients died. Enhanced surveillance in humans and animals and mosquito control measures were implemented. The WNV infections were included in the national notifiable diseases list as of April 2011. In 2011, three probable and two confirmed cases of WNV infection were diagnosed in provinces where infections had been detected in the previous year, supporting a lower activity than 2010. However,detection of WNV infections in humans in 2010 and 2011 consecutively, may indicate that WNV has become endemic in the western part of Turkey. Field epidemiological studies were undertaken to understand more about the nature of infection in Turkey.

We demonstrate burst-mode operation of a polarization-maintaining Yb-doped fiber amplifier. Groups of pulses with a temporal spacing of 10 ns and 1 kHz overall repetition rate are amplified to an average pulse energy of ∼20 μJ and total burst energy of 0.25 mJ. The pulses are externally compressed to ∼400 fs. The amplifier is synchronously pulsed-pumped to minimize amplified spontaneous emission between the bursts. We characterize the influence of pump pulse duration, pump-to-signal delay, and signal burst length.

In this study, a thulium (Tm:YAP) laser system was developed for brain surgery applications. As the Tm:YAP laser is a continuous-wave laser delivered via silica fibers, it would have great potential for stereotaxic neurosurgery with highest local absorption in the IR region. The laser system developed in this study allowed the user to set the power level, exposure time, and modulation parameters (pulse width and on-off cycles). The Tm:YAP laser beam (200-600 mW, 69-208 W/cm(2)) was delivered from a distance of 2 mm to cortical and subcortical regions of ex-vivo Wistar rat brain tissue samples via a 200-μm-core optical fiber. The system performance, dosimetry study, and ablation characteristics of the Tm:YAP laser were tested at different power levels by maximizing the therapeutic effects and minimizing unwanted thermal side-effects. The coagulation and ablation diameters were measured under microscope. The maximum ablation efficiency (100 × ablation diameter/coagulation diameter) was obtained when the Tm:YAP laser system was operated at 200 mW for 10 s. At this laser dose, the ablation efficiency was found to be 71.4% and 58.7% for cortical and subcortical regions, respectively. The fiber-coupled Tm:YAP laser system in hence proposed for the delivery of photothermal therapies in medical applications.

We demonstrate generation of pulses with up to 4 microJ energy at 1 MHz repetition rate through nonlinear chirped-pulse amplification in an entirely fiber-integrated amplifier, seeded by a fiber oscillator. The peak power and the estimated nonlinear phase shift of the amplified pulses are as much as 57 kW and 22pi, respectively. The shortest compressed pulse duration of 140 fs is obtained for 3.1 microJ of uncompressed amplifier output energy at 18pi of nonlinear phase shift. At 4 microJ of energy, the nonlinear phase shift is 22pi and compression leads to 170-fs-long pulses. Numerical simulations are utilized to model the experiments and identify the limitations. Amplification is ultimately limited by the onset of Raman amplification of the longer edge of the spectrum with an uncompressible phase profile.

Tm:YAP laser system at power levels up to 1.2 W at 1980 nm was established in both continuous-wave and modulated modes of operation. The fluence effect of the laser system for skin ablation was analyzed by histology analysis with Wistar rat skin tissues. Thermally altered length, thermally altered area, ablation area, and ablation depth parameters were measured on histology images of skin samples just after the laser operation and after four-day healing period. Continuous-wave mode of operation provided higher thermal effects on the skin samples. Lower fluence levels were found for efficient ablation effect.