Comprehension of wh-questions in a case of mixed dementia

We investigated processing of wh-questions and declarative sentences with differing syntactic complexity in a case of mixed dementia (FA). FA was impaired in her ability to understand syntactically complex declarative sentences and syntactically complex wh-questions beginning with which but not complex who questions. This profile, novel in dementia, is similar to that reported for people with agrammatic aphasia and discerns a ‘‘fault line’’ of the language system along a syntactic/semantic paramete

Adaptive phase shaping in a fiber chirped pulse amplification system

We demonstrate adaptive spectral phase shaping in a fiber chirped pulse amplification system. The adaptive process, controlled by a simulated annealing algorithm, resulted in three times improvement in the autocorrelation peak intensity of 65µJ pulses

Adaptively shaped mid-infrared pulses from a synchronously pumped optical parametric oscillator

Adaptively shaped, sub-picosecond pulses at 3.4µm are obtained from a synchronously pumped optical parametric oscillator based on periodically poled lithium niobate. A simulated annealing algorithm is used in a learning loop to gain adaptive control of the midinfrared idler pulse shape via shaping of a chirped near-infrared pump pulse. Both indirect control, via optimization of the signal average power, and direct control, via optimization of the two-photon absorption of the idler in an InGaAs detector, has been demonstrated. Both these optimization parameters lead to compressed idler pulses, with slightly differing pulse shapes. By optimization of the cross correlation signal in an interferometer with unequal arm lengths we are also able to deliver compressed double pulses with a variable time delay

Characterization of date palm fronds as a fuel for energy production

This study investigated the characteristics of date palm fronds (DPF) for their use as a feedstock for fuel and energy production. The calorific values and elemental contents of the DPF samples were measured through proximate analysis, ultimate analysis and energy dispersive X-ray spectroscopy. For proximate analysis, thermo-gravimetric analysis technique was used to identify the moisture content, volatile matter, fixed carbon and ash content. Ultimate analysis was used to determine the weight percentage of carbon, hydrogen and nitrogen. In line with this, X-ray fluorescence was used to determine the percentage of sulfur in the tested samples. The results of the conducted study were compared with other biomass reported in the past literature. The fixed carbon content of DPF was found lower than the other biomass except rice husk. Ajwah DPF exhibited the highest carbon content of 14.1%, while Jeddah DPF showed lowest carbon content of 5.2% among all the tested samples. However, presence of the metallic elements in the samples, such as Mg and Na can cause problems in the thermo-chemical processing systems

High energy femtosecond fiber chirped pulse amplification system with adaptive phase control

We demonstrate increased peak power from an Yb fiber CPA system operating with strong self-phase modulation by shaping the spectral phase of the input pulses. An adaptive control loop used feedback from the output autocorrelation. We investigated pre-compensation of both SPM phase distortion at high energies, and residual dispersion from mismatched stretcher/compressor technologies at low energies. Phase shaping resulted in improved pulse quality with the autocorrelation peak typically increased by a factor of three compared to unshaped pulses. High-quality 800 fs, 65 µJ recompressed pulses were produced. This technique could benefit a wide variety of fiber amplifier systems and is self-optimising for operation at both low and high pulse energies

High energy femtosecond fiber chirped pulse amplification system with adaptive phase control

We demonstrate threefold increased autocorrelation peak from an Yb-fiber CPA system operating with strong self-phase modulation by pre-shaping the pulse spectral-phase. The adaptive control loop used feedback from the output autocorrelation. High-quality 800 fs, 65 µJ recompressed pulses were produced