The Electron Transport Through Strongly Coupled Double Quantum Dots : Effect of Spin Exchange Interaction

We introduce  model calculation for the electron transport through a system consists of two serially coupled quantum dots, embedded between two nonmagnetic leads (source and drain). In our treatment, the time independent Anderson-Newns Hamiltonian model is considered as a basis to study the system dynamics and then to derive spin-dependent analytical formula to calculate the occupation numbers of the quantum dots energy levels, the corresponding quantum dots energy levels and the molecular virtual energy levels, as a function of bias voltage. These relations are solved self-consistently, which are all employed to calculate the tunneling current considering the strong coupling regime. The differential conductance is calculated numerically by using finite differences method. And as the efficiency of electron transport through coupled quantum dots depends on the system parameters, the effective exchange energy is highlighted and studied in details and the role of this parameter in the tunneling current and the differential conductance calculations is presented. Our treatment is utilized to study the following The role of the spin exchange interaction in determining the type of  interaction (if it is attractive or repulsive) between the quantum dots...

Emisija kratkovalnog zračenja tijekom udara iona o čvrstu površinu

The possibility of short-wave photon emission during surface scattering of positive ions is investigated by selection of the type of charge-exchange process (one- or two-electron processes), through the calculation of the neutralization probabilities and the charge-transfer cross sections. These probabilities are calculated statically as a function of distance between the incident ion and the surface, and dynamically as a function of the ion velocity. The model is applied to real systems such as He+/semiconductor (silicon and germanium), taking into account the difference in the physical constants of the two systems. We found that emitted photons have short wavelengths, lying in the ultraviolet range of the electromagnetic spectrum of the helium emission spectrum.Istražujemo mogućnost emisije kratkovalnih fotona tijekom udara iona o čvrstu površinu odabirom procesa izmjene naboja (jedno i dvoelektronski procesi) i računanjem vjerojatnosti neutralizacije i udarnog presjeka za prijenos naboja. Te vjerojatnosti računamo statički kao funkcije udaljenosti upadnog iona i površine, i dinamički kao funkcije brzine iona. Model primjenjujemo stvarnim sustavima kao što su poluvodiči silicij i germanij, uzimajući u obzir razlike fizičkih svojstava dvaju sustava. Nalazimo da fotoni imaju kratke valne duljine, u području elektromagnetskog spektra helija

NcPred for accurate nuclear protein prediction using n-mer statistics with various classification algorithms

Prediction of nuclear proteins is one of the major challenges in genome annotation. A method, NcPred is described, for predicting nuclear proteins with higher accuracy exploiting n-mer statistics with different classification algorithms namely Alternating Decision (AD) Tree, Best First (BF) Tree, Random Tree and Adaptive (Ada) Boost. On BaCello dataset [1], NcPred improves about 20% accuracy with Random Tree and about 10% sensitivity with Ada Boost for Animal proteins compared to existing techniques. It also increases the accuracy of Fungal protein prediction by 20% and recall by 4% with AD Tree. In case of Human protein, the accuracy is improved by about 25% and sensitivity about 10% with BF Tree. Performance analysis of NcPred clearly demonstrates its suitability over the contemporary in-silico nuclear protein classification research

Phase I/II Study of Refametinib (BAY 86-9766) in Combination with Gemcitabine in Advanced Pancreatic cancer

Background Activating KRAS mutations are reported in up to 90% of pancreatic cancers. Refametinib potently inhibits MEK1/2, part of the MAPK signaling pathway. This phase I/II study evaluated the safety and efficacy of refametinib plus gemcitabine in patients with advanced pancreatic cancer. Methods Phase I comprised dose escalation, followed by phase II expansion. Refametinib and gemcitabine plasma levels were analyzed for pharmacokinetics. KRAS mutational status was determined from circulating tumor DNA. Results Ninety patients overall received treatment. The maximum tolerated dose was refametinib 50 mg twice daily plus standard gemcitabine (1000 mg/m2 weekly). The combination was well tolerated, with no pharmacokinetic interaction. Treatment-emergent toxicities included thrombocytopenia, fatigue, anemia, and edema. The objective response rate was 23% and the disease control rate was 73%. Overall response rate, disease control rate, progression-free survival, and overall survival were higher in patients without detectable KRAS mutations (48% vs. 28%, 81% vs. 69%, 8.8 vs. 5.3 months, and 18.2 vs. 6.6 months, respectively). Conclusion Refametinib plus gemcitabine was well tolerated, with a promising objective response rate, and had an acceptable safety profile and no pharmacokinetic interaction. There was a trend towards improved outcomes in patients without detectable KRAS mutations that deserves future investigation

Pathological complete response after neoadjuvant chemotherapy is an independent predictive factor irrespective of simplified breast cancer intrinsic subtypes: a landmark and two-step approach analyses from the EORTC 10994/BIG 1-00 phase III trial

The present analysis, carried out in the context of a randomized phase III trial, confirms superior outcomes for breast cancer patients for whom chemotherapy induces pathological complete response (pCR) after adjusting for other important prognostic factors. In contrast, when tumours do not achieve pCR, patients have a higher risk of relapse. This effect is observed in all intrinsic subtypes and justifies the current interest in post-neoadjuvant trial