Resource Allocation for Hybrid NOMA MEC Offloading

Non-orthogonal multiple access (NOMA) and mobile edge computing (MEC) have been recognized as promising technologies for the beyond fifth generation networks to achieve significant capacity improvement and delay reduction. In this paper, the technologies of hybrid NOMA and MEC are integrated. In the hybrid NOMA MEC system, multiple users are classified into different groups and each group is allocated a dedicated time slot. In each group, a user first offloads its task by sharing a time slot with another user, and then solely offloads during a time interval. To reduce the delay and save the energy consumption, we consider jointly optimizing the power and time allocation in each group as well as the user grouping. As the main contribution, the optimal power and time allocation is characterized in closed form. In addition, by incorporating the matching algorithm with the optimal power and time allocation, we propose a low complexity method to efficiently optimize user grouping. Simulation results demonstrate that the proposed resource allocation method in the hybrid NOMA MEC systems not only yields better performance than the conventional OMA scheme but also achieves quite close performance as global optimal solution

Machine Learning to Build and Validate a Model for Radiation Pneumonitis Prediction in Patients with Non–Small Cell Lung Cancer

Purpose: Radiation pneumonitis is an important adverse event in patients with non–small cell lung cancer (NSCLC) receiving thoracic radiotherapy. However, the risk of radiation pneumonitis grade ≥ 2 (RP2) has not been well predicted. This study hypothesized that inflammatory cytokines or the dynamic changes during radiotherapy can improve predictive accuracy for RP2. Experimental Design: Levels of 30 inflammatory cytokines and clinical information in patients with stages I–III NSCLC treated with radiotherapy were from our prospective studies. Statistical analysis was used to select predictive cytokine candidates and clinical covariates for adjustment. Machine learning algorithm was used to develop the generalized linear model for predicting risk RP2. Results: A total of 131 patients were eligible and 17 (13.0%) developed RP2. IL8 and CCL2 had significantly (Bonferroni) lower expression levels in patients with RP2 than without RP2. But none of the changes in cytokine levels during radiotherapy was significantly associated with RP2. The final predictive GLM model for RP2 was established, including IL8 and CCL2 at baseline level and two clinical variables. Nomogram was constructed based on the GLM model. The model's predicting ability was validated in the completely independent test set (AUC = 0.863, accuracy = 80.0%, sensitivity = 100%, specificity = 76.5%). Conclusions: By machine learning, this study has developed and validated a comprehensive model integrating inflammatory cytokines with clinical variables to predict RP2 before radiotherapy that provides an opportunity to guide clinicians

Power Efficient IRS-Assisted NOMA

In this paper, we propose a downlink multiple-input single-output (MISO) transmission scheme, which is assisted by an intelligent reflecting surface (IRS) consisting of a large number of passive reflecting elements. In the literature, it has been proved that nonorthogonal multiple access (NOMA) can achieve the same performance as computationally complex dirty paper coding, where the quasi-degradation condition is satisfied, conditioned on the users’ channels fall in the quasi-degradation region. However, in a conventional communication scenario, it is difficult to guarantee the quasi-degradation, because the channels are determined by the propagation environments and cannot be reconfigured. To overcome this difficulty, we focus on an IRS-assisted MISO NOMA system, where the wireless channels can be effectively tuned. We optimize the beamforming vectors and the IRS phase shift matrix for minimizing transmission power. Furthermore, we propose an improved quasi-degradation condition by using IRS, which can ensure that NOMA achieves the capacity region with high possibility. For a comparison, we study zero-forcing beamforming (ZFBF) as well, where the beamforming vectors and the IRS phase shift matrix are also jointly optimized. Comparing NOMA with ZFBF, it is shown that, with the same IRS phase shift matrix and the improved quasi-degradation condition, NOMA always outperforms ZFBF. At the same time, we identify the condition under which ZFBF outperforms NOMA, which motivates the proposed hybrid NOMA transmission. Simulation results show that the proposed IRS-assisted MISO system outperforms the MISO case without IRS, and the hybrid NOMA transmission scheme always achieves better performance than orthogonal multiple access

Screening of specific diagnostic peptides of swine hepatitis E virus

© 2009 Zhao et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution Licens

Second-Line Combination Chemotherapy with Docetaxel and Nedaplatin for Cisplatin-Pretreated Refractory Metastatic/Recurrent Esophageal Squamous Cell Carcinoma

Background:There is an urgent need for an effective second-line chemotherapy regimen after failure of the standard cisplatin and 5-fluorouracil therapy.Patients and Methods:This study investigated the efficacy and toxicity of the combination of docetaxel (30 mg/m2) during a 1-hour infusion, followed by nedaplatin (50 mg/m2) during a 2-hour infusion (both drugs were administered on day 1 as an outpatient regimen and repeated every 2 weeks) as second-line chemotherapy for patients with cisplatin-pretreated refractory metastatic/recurrent esophageal squamous cell carcinoma after surgery.Results:Forty-six of the 48 patients (95.8%) were assessable for response. Partial response was confirmed in 13 of 48 cases yielding a response rate of 27.1% (95% confidence interval [CI], 14.5–39.7%). The median overall time to progression and overall survival was 3.1 months (95% CI, 2.3–3.9 months) and 5.9 months (95% CI, 3.9–7.8 months), respectively. The estimate of overall survival at 12 months was 16.7% (95% CI, 6.1–27.2%). Grade 3 anemia leucopenia, grade 4 anemia leucopenia and neutropenia were detected in only 4 (8.7%), 8 (17.4%), and 9 patients (19.6%), respectively.Conclusions:The combination chemotherapy of docetaxel and nedaplatin in the outpatient setting is well tolerated and useful as second-line chemotherapy for cisplatin-pretreated refractory metastatic/recurrent esophageal squamous cell carcinoma

Doses of radiation to the pericardium, instead of heart, are significant for survival in patients with non-small cell lung cancer

Background and purpose: Higher cardiac dose was associated with worse overall survival in the RTOG0617 study. Pericardial effusion (PCE) is a common cardiac complication of thoracic radiation therapy (RT). We investigated whether doses of radiation to the heart and pericardium are associated with PCE and overall survival in patients treated with thoracic radiation for non-small cell lung cancer (NSCLC). Materials and Methods: A total of 94 patients with medically inoperable/unresectable NSCLC treated with definitive RT in prospective studies were reviewed for this secondary analysis. Heart and pericardium were contoured consistently according to the RTOG1106 Atlas, with the great vessels and thymus of the upper mediastinal structures included in the upper part of pericardium, only heart chambers included in the heart structure. Clinical factors and dose-volume parameters associated with PCE or survival were identified via Cox proportional hazards modeling. The risk of PCE and death were mapped using DVH atlases. Results: Median follow-up for surviving patients was 58 months. The overall rate of PCE was 40.4%. On multivariable analysis, dosimetric factors of heart and pericardium were significantly associated with the risk of PCE. Pericardial V30 and V55 were significantly correlated with overall survival, but presence of PCE and heart dosimetric factors were not. Conclusion: PCE was associated with both heart and pericardial doses. The significance of pericardial dosimetric parameters, but not heart chamber parameters, on survival suggests the potential significance of radiation damage to the cranial region of pericardium

Genetic Variations in the Transforming Growth Factor-β1 Pathway May Improve Predictive Power for Overall Survival in Non-small Cell Lung Cancer

Purpose: Transforming growth factor-β1 (TGF-β1), a known immune suppressor, plays an important role in tumor progression and overall survival (OS) in many types of cancers. We hypothesized that genetic variations of single nucleotide polymorphisms (SNPs) in the TGF-β1 pathway can predict survival in patients with non-small cell lung cancer (NSCLC) after radiation therapy. Materials and Methods: Fourteen functional SNPs in the TGF-β1 pathway were measured in 166 patients with NSCLC enrolled in a multi-center clinical trial. Clinical factors, including age, gender, ethnicity, smoking status, stage group, histology, Karnofsky Performance Status, equivalent dose at 2 Gy fractions (EQD2), and the use of chemotherapy, were first tested under the univariate Cox's proportional hazards model. All significant clinical predictors were combined as a group of predictors named "Clinical." The significant SNPs under the Cox proportional hazards model were combined as a group of predictors named "SNP." The predictive powers of models using Clinical and Clinical + SNP were compared with the cross-validation concordance index (C-index) of random forest models. Results: Age, gender, stage group, smoking, histology, and EQD2 were identified as significant clinical predictors: Clinical. Among 14 SNPs, BMP2:rs235756 (HR = 0.63; 95% CI:0.42-0.93; p = 0.022), SMAD9:rs7333607 (HR = 2.79; 95% CI 1.22-6.41; p = 0.015), SMAD3:rs12102171 (HR = 0.68; 95% CI: 0.46-1.00; p = 0.050), and SMAD4: rs12456284 (HR = 0.63; 95% CI: 0.43-0.92; p = 0.016) were identified as powerful predictors of SNP. After adding SNP, the C-index of the model increased from 84.1 to 87.6% at 24 months and from 79.4 to 84.4% at 36 months. Conclusion: Genetic variations in the TGF-β1 pathway have the potential to improve the prediction accuracy for OS in patients with NSCLC

Nucleolus disassembly and distribution of segregated nucleolar material in prophase of root-tip meristematic cells in Triticum aestivum L.

This paper presents details of the process of nucleolar disassembly, studied by conventional transmission electron microscopy (TEM) in wheat root cells. In early prophase, chromatin condensation and irregular nucleolar morphology are observed, with many small particles appearing around the nucleolus. In middle prophase, the nucleolus radiates outwards; in late prophase, the fine structure of the nucleolus disappears and nucleolar material diffuses away. Using “en bloc” silver-staining to distinguish between nucleoli and chromatin, we observed that the dispersed nucleolar material aggregates around the chromatin, forming a sheath-like perichromosomal structure that coats the chromosomes in late prophase

Development of red giant embryo rice by molecular marker-assisted selection

In this study,we successfully developed a new rice (Oryza Sativa L.) strain of red giant embryo rice "Shangshida No. 10" by hybridizing a normal embryo red rice "Shangshida No. 6" with a giant embryo white rice "Shangshida No. 5" and backcrossing with "Shangshida No. 5",together by molecular marker-assisted selection. There was no significant difference in the weight per plant between "Shangshida No. 5" and "Shangshida No. 10",but the yield of "Shangshida No. 10" was significantly higher than that of "Shangshida No. 5" as shown in field trials,while growth duration of "Shangshida No. 10" was approximately 4~5 days shorter than that of "Shangshida No. 5". In addition,weight ratio of embryo to brown rice of "Shangshida No. 10" was lower than that of "Shangshida No. 5",while there was no significant difference in the volume ratio of embryo to brown rice between "Shangshida No. 10" and "Shangshida No. 5". The successful development of the new rice strain "Shangshida No. 10" has laid a solid foundation for the further market development and application of red giant embryo rice