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This was a nationwide population-based retrospective cohort study to investigate the risk of developing deep-vein thrombosis (DVT) and pulmonary embolism (PE) in patients with a pneumococcal pneumonia.We analysed data from 1998 to 2010 from the Taiwan National Health Insurance Database. The follow-up period was extended to the end of 2011. We identified patients with pneumococcal pneumonia and selected a comparison cohort matched for age, sex and diagnosis year at a ratio of one pneumococcal pneumonia patient to four control patients. We analysed the risks of DVT and PE by using Cox proportional hazards regression models, including gender, age and comorbidities.In total, 18,928 pneumococcal pneumonia patients and 75,712 controls were included in the study. The risks of developing DVT and PE were 1.78-fold (95% CI: 1.39-2.28) and 1.97-fold (95% CI: 1.43-2.72), respectively, in patients with pneumococcal pneumonia compared to the control cohort after adjusting for age, gender and comorbidities. The increased risks of DVT and PE were significant in patients who exhibited any comorbidity. The incidences of DVT and PE were highest in the first 4 weeks after pneumonia and remained slightly elevated from 13 weeks to 2 years after acute infection.Pneumococcal pneumonia should be considered a risk factor for DVT and PE, even after the patient has recovered from the acute infection.

Adrenal insufficiency is an uncommon and easily ignored cause among most etiologies of hypercalcemia because not all cases of adrenal insufficiency presented with hypercalcemia. In most cases of adrenal insufficiency, viral encephalitis-related panhypopituitarism is a rare complication that is sporadically encountered in previous studies. However, this complication has never been reported in rabies encephalitis because of the extremely high rate of mortality. Rapid recovery from hypercalcemia state after glucocorticoid supplement is a direct hint of adrenal insufficiency related hypercalcemia.

BACKGROUND:The common differential diagnosis of microcytic anemia in young Asian men includes iron deficiency anemia (IDA), α-thalassemia (αT) and β-thalassemia (βT). In this study, we aimed to distinguish between these diseases in a distinct population of young men using a specific index. PATIENTS AND METHODS:We retrospectively reviewed the laboratory data of young men with microcytic anemia. The clinical, characteristic and laboratory data, including complete blood cell counts, serum ferritin and hemoglobin electrophoresis results, were collected; genomic DNA mutations were also evaluated. Based on these data, ten discrimination indices were used to differentiate thalassemia from IDA. The sensitivity, specificity, positive and negative predictive values, Youden's index and receiver operating characteristic (ROC) curves were also calculated. RESULTS:A total of 877 patients (92 patients with IDA, 332 with αT and 453 with βT) were enrolled; the Shine and Lal (S&L) formula was the best method with which to discriminate IDA from thalassemia (100% sensitivity, 91% specificity). The new cut-off values were evaluated, and the approaches used in our study cohort, particularly the Green & King (G&K) formula, significantly increased the accuracies of red cell distribution width-containing indices (cut-off value: 58.66; 89.62% sensitivity and 96.2% specificity; AUC: 0.9716). In addition, when applied properly, these indices could differentiate IDA patients from αT patients, especially Huber-Herklotz index (HH). CONCLUSIONS:The sensitivity and specificity differed among ethnic and age groups. We concluded that when using the original cut-off value, the S&L formula was the best discriminating index for differentiating between IDA and thalassemia in young Asian men. However, when using the G&K formula, the newly obtained cut-off value must be applied to increase accuracy based on the results from our cohort.

Sub-threshold designs play an important role in energy-constrained applications. In those designs, path delays depend exponentially on threshold voltage/temperature. As such, dynamic configurations at runtime are desired for best trade-off between operating power and performance. Unfortunately, most existing works only consider either process or temperature variations but not both, resulting in sub-optimal configurations or even functional failures. Moreover, little study has been performed on the graceful degradation of sub-threshold designs, which is important in the presence of drastic delay variations. Towards this, we present a novel critical path monitor based dynamic voltage scaling scheme. Considering both process and temperature variations, it minimizes the operating power under a given timing error probability (TEP) bound. An exact method to decide the optimal switching thresholds is also proposed. Experimental results on 45nm industrial designs show that with only 1% TEP, our scheme can reduce the operating power by up to 75.3% compared with the constant voltage scheme. To the best of the authors' knowledge, this is the very first work on dynamic configuration for graceful degradation in sub-threshold designs.

SummaryStudies on the association between chronic osteomyelitis and deep vein thrombosis (DVT) and pulmonary thromboembolism (PE) are scarce. The aim of this study was to analyse a nationwide population-based database for association between DVT or PE after a diagnosis of chronic osteomyelitis. This nationwide population-based cohort study was based on data obtained from the Taiwan National Health Insurance Database from 1998 to 2008, with a follow-up period extending to the end of 2010. We identified patients with chronic osteomyelitis using International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes. The patients with chronic osteomyelitis and comparison controls were selected by 1:1 matching on a propensity score. The propensity score was calculated by a logistic regression to estimate the probability of the treatment assignment given the baseline variables including age, sex, and Charlson comorbidity index score. We analysed the risks of DVT and PE by using Cox proportional hazards regression models, including sex, age, and comorbidities. In total, 24,335 chronic osteomyelitis patients and 24,335 controls were enrolled in the study. The risk of developing DVT was 2.49-fold in patients with chronic osteomyelitis compared with the comparison cohort, after adjusting for age, sex, and comorbidities. The multiplicative increased risks of DVT were also significant in patients with chronic osteomyelitis with any comorbidity. In conclusion, physicians should consider chronic osteomyelitis in their evaluation of risk factors for DVT.

A special kind of bosonization technique and renormalization group theory are employed to study an extended ferromagnetic Kondo lattice model. An effective Hamiltonian is deduced. On the basis of this effective Hamiltonian the phase diagram is discussed, and the effects of the introduced Hund anisotropy and antiferromagnetic interaction between the local spins are clarified. The on-site interaction between the conduction electrons contributes to the effective ferromagnetic interaction between the local spins through the Hund interaction.

The phonon effects on a multichannel resonant-level model have been studied by a bosonization technique and canonical transformations. We found that the model can be mapped onto a single-channel Kondo model and the non-Fermi-liquid transition is modified by local electron - phonon interaction. At strong interaction, only one channel of conducting electrons is necessary in order to realize this transition and it is the phonon effects that control the behaviour of the system.

This paper reports a closed-form analytical drain current model considering both electron and lattice temperatures simultaneously using a quasi-two-dimensional approach for deep submicron ultrathin SOI NMOS devices. As verified by the experimental data, the closed-form analytical model shows a good predication of the negative differential resistance behavior. Based on the analytical model, with a channel length of >

Retention registers have been widely used in power gated design to store data during sleep mode. Since they consume much larger area and power than normal registers, it is imperative to minimize the total retention storage size. The current industry practice only replace all registers with single-bit retention ones, which significantly limits the design freedom and results in excessive area and power overhead. Towards this, for the first time in literature, we propose the concept of multi-bit retention register, with which only selected registers need to be replaced. It can significantly reduce the number of bits that need to be stored and thus the area and leakage power, but needs several clock cycles for mode transition. In addition, an efficient assignment algorithm is developed to minimize the total retention storage size subject to mode transition latency constraint. Experimental results show that our framework on average can reduce the leakage power in sleep mode and the retention storage area by 66.03%, compared with the single-bit retention register based design.

We study the ground-state fidelity and entanglement of a Bose–Fermi mixture loaded in a one-dimensional optical lattice. It is found that the fidelity is able to signal quantum phase transitions between the Luttinger liquid phase, the density-wave phase, and the phase separation state of the system, and the concurrence, as a measure of the entanglement, can be used to signal the transition between the density-wave phase and the Ising phase. (Some figures in this article are in colour only in the electronic version)

Background A villous adenoma is an extremely rare benign tumour in the appendix, in contrast to other benign appendiceal lesions. The clinical features are usually asymptomatic. Acute appendicitis is the most common complication with the lesion obstructing the orifice of the appendiceal lumen. Thus, a villous adenoma is usually found during surgical intervention for acute appendicitis. Mechanical obstruction induced by acute perforated appendicitis has been previously reported. Acute appendicitis caused by a villous adenoma presenting with acute intestinal obstruction has not been previously reported. Case presentation A 78-year-old woman presented to our Emergency Department with diffuse abdominal pain and tenderness. The abdominal plain film and computed tomography revealed an intestinal obstruction. After surgical intervention, the ruptured appendix was shown to be associated with intestinal obstruction. The post-operative pathologic diagnosis was an appendiceal villous adenoma. Conclusions This is the first report describing an appendiceal villous adenoma, which is an occasional cause of perforated acute appendicitis, presenting as a complete intestinal obstruction. We emphasize that in elderly patients without a surgical history, the occult cause of complete intestinal obstruction must be determined. If an appendiceal tumour is diagnosed, an intra-operative frozen section is suggested prior to selecting a suitable method of surgical intervention.

Mono-chemotherapy with gemcitabine (difluorodeoxycytidine) is an effective cancer chemotherapy, and is often used instead of a more effective but more toxic combination chemotherapy regimen. Infection associated with gemcitabine is very rare. We present a case of Cryptococcus neoformans pneumonia that developed after 5 courses of gemcitabine for advanced bladder carcinoma. Lung biopsy and antigens demonstrated C. neoformans. The pneumonia resolved after antifungal therapy.

To evaluate of the role of transcranial electrical stimulation motor evoked potential (TES-MEP) in combination with cortical somatosensory evoked potential (CSEP) monitoring during the spinal surgery.TES-MEP on bilateral anterior tibial muscle and flexor hallucal brevis and CSEP on bilateral posterior tibial nerve were observed simultaneously on 293 patients during spinal surgery from July 2006 to April 2009. Intravenous anesthesia was employed in all the patients, a part of which were added low dose of sevoflurane or muscle relaxant. The results of TES-MEP, CSEP and combined monitoring were analyzed statistically. Pre-operative and post-operative motor and sensory functions of spinal cord were compared.Success rate of TES-MEP, CSEP and combined monitoring was 90.8%, 96.9% and 100% respectively. For the judgment of motor function of spinal cord, the sensitivity of TES-MEP and CSEP was 100% and 89.3% respectively and the specificity of 98.4% and 96.9%. The Youden index of the two methods was 0.984 and 0.862. For sensory function, the sensitivity of them was 76.7% and 93.3% respectively and the specificity of 98.7% and 98.0%. The Youden index was 0.754 and 0.913. The sensitivity of combined monitoring was 100%, with the specificity of 96.9%. The Youden index was 0.969.The precision of monitoring motor function of spinal cord with TES-MEP is higher than that with CSEP, however, for sensory function, CSEP is more precise. The sensitivity and precision of combined monitoring for spinal cord function were apparently better than that of unitary TES-MEP or CSEP. The combined TES-MEP and CSEP monitoring is a relatively ideal method.

Objective: Extracorporeal membrane oxygenation (ECMO) offers temporary haemodynamic support for those with refractory cardiogenic shock after cardiac surgery. We review our 5-year experience regarding ECMO use on those who cannot be weaned from cardiopulmonary bypass after cardiac surgery. We analyse our cases, predict the prognostic factors of survival and compare the short-term and medium-term results. Methods: From January 2002 to December 2006, 1764 patients underwent cardiac surgery with cardiopulmonary bypass in our division. Among these, 51 patients (2.9%) required venoarterial-mode ECMO for haemodynamic support because of refractory postcardiotomy cardiogenic shock. The indication of ECMO was refractory cardiogenic shock despite adequate filling volumes, large-dose inotropes and intra-aortic balloon pump support. The following cardiac surgical procedures were performed: coronary artery bypass grafting (CABG), n = 27; valvular surgery, n = 11; CABG plus valvular surgery, n = 7; heart transplantation, n = 4 and other procedures, n =2 .Results: Average age was 63.0 15.7 years. There were 36 male and 15 female patients. Average duration of ECMO was 7.5 6.7 days. Twenty-seven (53%) patients could be successfully weaned from ECMO. The 30-day and 3-month mortalities were 49% (25/51) and 65% (33/51). The in-hospital mortality was 67% (34/51 patients). Seventeen (33%) patients could be successfully discharged. Fifteen (29%) patients were still alive at 1-year outpatient department (OPD) followup. Conclusions: ECMO provides a good temporary cardiopulmonary support in patients with postcardiotomy shock. The preoperative risk factors of failure to withdraw ECMO are poor left-ventricular ejection fraction, systolic blood pressure

To approach the effects of exogenous metallothionein (Zn-MT) on the thermoresistance and SOD gene expression of dairy cattle, an experiment was conducted with 28 lactating cows, which were randomly allocated to groups A, B, C and D, and supplemented with 0, 6.0, 12.0 and 16.0 mg Zn-MT x capita(-1), respectively, by intravenous injection. The results showed that the pulse, breath rate, and serum MDA content of the cows in groups B, C and D were lower (P0.05 or P0.01), while their milk yield, serum- and milk MT contents, blood GSH-PX activity, erythrocyte SOD activity, and SOD gene expression level were higher (P0.05 or P0.01) than those in group A. All the test indices of the cows in groups C and D were superior (P0.05 or P0.05) than those in group B, but no significant difference (P0.05) was observed between groups C and D. Exogenous Zn-MT had the best effects on the thermoresistance and SOD gene expression of dairy cattle 30 days after injection. All of these suggested that exogenous Zn-MT should be a physiologically active substance effective to the thermoresistance and SOD mRNA expression of dairy cattle, and presented time- and dose-dependent effects.

Acetaminophen (APAP) intoxication is a common cause of hepatic toxicity and life-threatening hepatic failure. However, few studies have investigated the possible association between APAP intoxication and acute kidney injury (AKI). We constructed a retrospective cohort study to clarify the relationship between APAP intoxication and the risk of AKI. We identified patients with APAP intoxication and selected a comparison cohort that was 1:4 frequency matched according to age, sex, and year of APAP intoxication diagnosis from the Taiwan National Health Insurance Research Database from 1998 to 2010. We analyzed the risks of AKI for patients with APAP intoxication by using Cox proportional hazards regression models. In this study, 2914 patients with APAP intoxication and 11,656 controls were included. The overall risks of developing AKI were 2.41-fold in the patients with APAP intoxication compared with the comparison cohort. After we excluded APAP intoxication patients with coexisting AKI and hepatic failure/hepatitis, the overall risks of developing AKI were still 2.22-fold in the patients with APAP intoxication. There were 2 patients who had end-stage renal disease (ESRD) following APAP intoxication-related AKI. Limitations include retrospective review, selection bias, and absence of data on detail medications used, laboratory investigations and dosage of APAP intoxication. Our long-term cohort study results showed that AKI is a possible adverse effect among patients with APAP intoxication, regardless of whether patients have presented with hepatic toxicity. However, additional studies are necessary to clarify whether such patients can progress to ESRD.

Supplemental Digital Content is available in the text, The current retrospective study aimed to investigate the relationship between prognostic factors and overall survival (OS) in patients with advanced pancreatic head cancers who initially presented with obstructive jaundice. Furthermore, the impact of age and comorbidities on therapeutic strategies in such patients was evaluated. A total of 79 advanced pancreatic head cancer patients who were treated at our institution between January 2006 and November 2013 were reviewed. We analyzed OS risk factors including sex, age, laboratory characteristics, Eastern Cooperative Oncology Group performance status, Charlson Comorbidity Index Scores (CCIS), and therapeutic strategies using Cox proportional hazards regression models. There was no difference in the OS of patients according to the type biliary drainage procedure they underwent. Other related factors, such as better performance status, lower CCIS, and receiving chemotherapy significantly correlated with survival in multivariate analyses. There was a significant survival benefit in systemic chemotherapy compared to best supportive care (BSC) or local radiotherapy. However, no survival benefit was found in elderly patients (age >70 years) undergoing systemic therapy compared to younger patients, except in those elderly patients with CCIS ≤ 1. In advanced pancreatic head cancer patients with obstructive jaundice, systemic therapy and adequate biliary drainage were still the most effective procedures for improving OS in the general population. However, in elderly patients with relatively higher CCIS, BSC with adequate biliary drainage was palliative and no less effective than systemic/local therapies.

The neutrophil/lymphocyte ratio (NLR), lymphocyte/monocyte ratio (LMR), and absolute lymphocyte count/absolute monocyte count prognostic score (ALC/AMC PS) have been described as the most useful prognostic tools for patients with diffuse large B-cell lymphoma (DLBCL). We retrospectively anal

Within a Su–Schriffer–Heeger model modified to include electron-electron interaction and an external electric field, we investigate the dynamics of oppositely charged polarons in a polymer chain in the presence of both electron-phonon and electron-electron interactions under the influence of an external electric field. We adopt a multi-configurational time-dependent Hartree–Fock method for the time-dependent Schrodinger equation and the Newtonian equation of motion for a lattice. Our results show that the on-site Coulomb interaction is of fundamental importance and favors the recombination between the pairs of polarons, and the yield of excitons depends crucially on the strength of the on-site Coulomb interaction U. Furthermore, the influence of the nearest neighbor interaction V is also discussed.

Based on the mechanism of pathophysiology, thalassemia major or transfusion-dependent thalassemia patients may have an increased risk of developing organic erectile dysfunction resulting from hypogonadism. However, there have been few studies investigating the association between erectile dysfunction and transfusion-naive thalassemia populations. We constructed a population-based cohort study to elucidate the association between transfusion-naive thalassemia populations and organic erectile dysfunction This nationwide population-based cohort study involved analyzing data from 1998 to 2010 obtained from the Taiwanese National Health Insurance Research Database, with a follow-up period extending to the end of 2011. We identified men with transfusion-naive thalassemia and selected a comparison cohort that was frequency-matched with these according to age, and year of diagnosis thalassemia at a ratio of 1 thalassemia man to 4 control men. We analyzed the risks for transfusion-naive thalassemia men and organic erectile dysfunction by using Cox proportional hazards regression models. In this study, 588 transfusion-naive thalassemia men and 2337 controls were included. Total 12 patients were identified within the thalassaemia group and 10 within the control group. The overall risks for developing organic erectile dysfunction were 4.56-fold in patients with transfusion-naive thalassemia men compared with the comparison cohort after we adjusted for age and comorbidities. Our long-term cohort study results showed that in transfusion-naive thalassemia men, there was a higher risk for the development of organic erectile dysfunction, particularly in those patients with comorbidities.

A new design and actual scheme of car electronic ignition control system based on curving surface-fitting algorithm is introduced. The strategy is also discussed. The data storage scheme of applying this strategy to develop control system is deeply discussed. The fitting points-searching during offline fitting, the creating of curving surface-fitting equation coefficient, and the search algorithm of curving surface in online real-time ignition are presented. The feasibility and reliability of this system are validated. The evident amelioration of dynamics and economics are achieved.

To investigate the veracity of cortical somatosensory evoked potential (CSEP) and the influencing factors of manipulation of CSEP monitoring during the operation for cervical spondylitic myelopathy (CSM).Sixty-eight CSM patients, 45 males and 23 females, aged 52.3, underwent CSEP monitoring at the ulnar, median, and posterior tibial nerves. The impact and level to CSEP of different period and manipulation during operation were recorded. The spinal cord function of post-operation were analyzed and evaluated.The CSEP monitoring was successful in all cases. CSEP pre-warning appeared 44 times in 24 cases. Among them 31 times of common pre-warning of CSEP were recorded because of operative manipulations and all of the 31 times of common pre-warning recovered after careful manipulation. Dangerous pre-warning was recorded for 11 times, and then the operation had to be stopped to search for the causes and awaken test was needed in one case. When the agents causing dangerous pre-warning of CSEP were found and corrected, the CSEP was able to recover. Not a patient showed aggravation of nervous function damage and no false negative result was found.CSEP can monitor the spinal cord function immediately and exactly. The main factors of operative manipulation causing pre-warning of CSEP include overextension and overflexion, overbrazing the space, operative manipulations for spinal cord thorough decompression, and overdeepening of graft.

This paper explores the tracers deployment problem for IP traceback methods how many and where the tracers should be deployed in the network to be effective for locating the attack origins. The minimizing the number of tracers deployment problems depended on locating the attack origins are defined. The problem is proved to be NP-complete. A heuristic method which can guarantee that the distance between any attack origin and its first met tracer be within an assigned distance is proposed. The upper bound for the probability of an undetected attack node can be calculated in advance and used to evaluate the number of tracers needed for the proposed heuristic method. Extended simulations are performed to study the performance of the tracers deployment.

Because the parameters of car-engines are of the discreteness, nonlinear and uncertain characteristics, a conventional control model can not accurately control the excess air coefficient and the spark advance angle in dynamic procedures. A new auto-optimized fuzzy control model based on genetic arithmetic was introduced. The controller design scheme based on using an embedded operating system to achieve such a control model was discussed. Based on a real-time simulation, using GA resulted in the fuzzy control parameters being optimized automatically. The results of experiments showed that the dynamic indexes and the fuel economy indexes can be improved greatly. The model has the obvious advantage of reducing fuel consumption.

Gamma-aminobutyric acid type A (GABA(A)) receptors are the major sites of inhibitory action of fast synaptic neurotransmission in the brain. Their receptors are also widely distributed in peripheral and endocrine tissues. A full-length cDNA encoding a novel splice variant of beta3 subunit of GABA(A) receptor, designated as beta3t, was identified in rat testis. This isoform contains a segment, having identical amino acid sequence as the beta3 subunit of neuronal GABA(A) receptors except for a section composed of 25 different amino acid sequence in the N-terminus. Northern blot shows that this isoform is found in rat testis. The beta3t isoform mRNA was detected in germ cells in the late step of spermatogenesis by in situ hybridization assay. Results of immunohistochemical and immunocytochemical assays indicate that the beta3t isoform is expressed in rat testis and spermatozoa. To determine a possible function of the N-terminal 25 amino acid segment, a recombinant plasmid of beta3t-EGFPC was constructed by fusing green fluorescent protein to the C-terminus of the beta3t isoform. The chimera product failed to be translocated unto the cell surface when expressed in HEK 293 cells; whereas, the beta3 subunit of rat brain is incorporated into the plasma membrane. In conclusion, the present results show that one variant of beta3 subunit of GABA(A) receptor, designated as beta3t, is found in germ cells of rat testis and sperm. The inability of the beta3t variant to target into the plasma membrane maybe a consequence of the unique 25 amino acid segment in the N-terminus.

This research was performed to investigate the relationship between 16 candidate genes responsible for dopaminergic transmission or iron metabolism and familial restless legs syndrome. Genotyping was performed in a Han restless legs syndrome family using the technique of fluorescence-based genescan with the microsatellite markers selected in chromosomal regions flanking the candidate genes. Classical linkage analysis was conducted under the autosomal dominant genetic mode. Results showed that all of the LOD scores at recombination fraction 0.00 are smaller than -2.00, which indicated that these loci were not linked to familial restless legs syndrome. No linkage was found between the candidate genes and RLS in this family. Familial restless legs syndrome may be caused by another gene related to dopaminergic transmission and iron metabolism or there is new mechanism involved in this disease.

We studied theoretically the spin-dependent electron transport properties of a three-terminal nanostructure proposed by Xiao and Chen [J. Appl. Phys.1, 108 (2010)]. The spin-resolved recursive Green's function method is used to calculate the three-terminal spin-polarization. We focus on the influence both of the structural parameters and Rashba spin–orbit coupling (SOC) strength in the investigated system. It is shown that the spin-polarization is still a reasonable value for being observable in experiment with small Rashba SOC strength and longer length of the wide region in the investigated system. The underlying physics is revealed to originate from the effect of SOC-induced effective magnetic field at the structure-induced Fano resonance. This length of the middle wide region in three-terminal nanostructure can be more easily fabricated experimentally.

A two-leg S = 1/2 spin ladder with ferromagnetic rung coupling is investigated to reveal the phase transition between the Haldane and columnar dimer phase. The elastic lattice with the elastic force K is introduced into the system, which induces unstable spin chains towards the spontaneous dimerization. When the rung coupling is strong enough, the dimerization along the legs is suppressed and the spin ladder undergoes a phase transition. The dimerization amplitude is calculated self-consistently by the density-matrix renormalization group method. To determine the phase transition boundary, the spin gap, the columnar dimer order parameter and the block-block entanglement entropy are calculated. Our results show that the phase boundary between the columnar dimer phase and Haldane phase follows the power law Jt ~ K−α.

By employing an adaptive time-dependent density matrix renormalization group (t-DMRG) method, we investigate the electron-electron correlation effects on the inelastic-scattering processes of oppositely charged-soliton anti-soliton pairs in conjugated polymers under the influence of an external electric field. The simulations are performed based on the Su-Schrieffer-Heeger (SSH) model modified to include electron-electron interactions and an external electric field. The percent yield of product is numerically calculated by a projection method. Our results show that the on-site Coulomb interaction is of fundamental importance and favors the recombination between the pairs of soliton. Additionally, the effects of external electric field and nearest-neighbor electron-electron interaction on the collision processes are also discussed.

The phase diagram of quasi-one-dimensinal model, which is most relevant to a kind of organic ferromagnets is considered. In this model, strong electron-phonon interaction is considered adiabatically and the coupling between local spin and it-electron is treated by a mean field theory. Full phase diagram is given. The results show that there are two kinds of new phase.

A scheme of an all-electrical spin conductance diode is proposed that uses a step-like quantum wire with Rashba spin-orbit interaction, connected to two leads with different width. It is shown that a very large spin conductance can be obtained when electrons transmit from the narrow lead to the wide lead, however, it vanishes or becomes very small when the transport direction is reversed. This difference is revealed to arise from the different local density of electron states of the quantum wire, which is dependent on the direction of bias. The spin conductance in the proposed structure can be generated and manipulated by purely electrical means and with strong a robustness against disorder, displaying the feasibility of this structure for a real application.

By employing an adaptive time-dependent density-matrix-renormalization-group method, the spin-flip process of polarons is investigated in a polymer chain with magnetic impurities. Being driven by an external electric field, a polaron carrying both spin 1/2 and charge e moves at a constant speed in the polymer chain. When the polaron passes through a specific site, which couples to a magnetic impurity via spin-exchange interaction, a spin-flip process is observed if its spin is antiparallel to the impurity spin. Our results show that the spin-flip probability is enhanced by the on-site Coulomb interaction and increases with increase in the spin-exchange integral. Additionally, some possible applications of the spin-state swap between the polaron and the impurity are discussed. © 2009 American Institute of Physics. doi:10.1063/1.3247189