A Theoretical Approach Involving Recurrence Resolution, Dependence Cycle Statement Ordering and Subroutine Transformation for the Exploitation of Parallelism in Sequential Code.

To exploit parallelism in Fortran code, this dissertation consists of a study of the following three issues: (1) recurrence resolution in Do-loops for vector processing, (2) dependence cycle statement ordering in Do-loops for parallel processing, and (3) sub-routine parallelization. For recurrence resolution, the major findings include: (1) the node splitting algorithm cannot be used directly to break an essential antidependence link, of which the source variable that results in antidependence is itself the sink variable of another true dependence so a correction method is proposed, (2) a sink variable renaming technique is capable of breaking an antidependence and/or output-dependence link, (3) for recurrences formed by only true dependences, a dynamic dependence concept and the derived technique are powerful, and (4) by integrating related techniques, an algorithm for resolving a general multistatement recurrence is developed. The performance of a parallel loop is determined by the level of parallelism and the time delay due to interprocessor communication and synchronization. For a dependence cycle of a single parallel loop executed in a general synchronization mode, the parallelism exposed varies with the alignment of statements. Statements are reordered on the basis of execution-time of the loop as estimated at compile-time. An improved timing formula and a derived statement ordering algorithm are proposed. Further extension of this algorithm to multiple perfectly nested Do-loops with simple global dependence cycle is also presented. The subroutine is a potential source for parallel processing. Several problems must be solved for subroutine parallelization: (1) the precedence of parallel executions of subroutines, (2) identification of the optimum execution mode for each subroutine and (3) the restructuring of a serial program. A five-step approach to parallelize called subroutines for a calling subroutine is proposed: (1) computation of control dependence, (2) approximation of the global effects of subroutines, (3) analysis of data dependence, (4) identification of execution mode, and (5) restructuring of calling and called subroutines. Application of these five steps in a recursive manner to different levels of calling subroutines in a program addresses the parallelization of subroutines

Clinicopathologic Evaluation of Prognostic Factors for Squamous Cell Carcinoma of the Buccal Mucosa

BackgroundThe purpose of this research was to evaluate the prognostic significance of clinicopathologic variables on the survival rate for squamous cell carcinoma of the buccal mucosa (BMSCC). We analyzed the outcomes of surgical therapy for this aggressive cancer and compared these results with those in the literature.MethodsWe reviewed the medical charts of 172 patients treated in our institution between 1990 and 2005. There were 22 patients excluded from our studies: 20 patients with advanced tumors who received no treatment or palliative treatment, and 2 patients who had received preoperative radiotherapy (RT). The remaining 150 patients were treated with surgeries and among them, 56 patients had undergone postoperative RT. The influence of clinicopathologic factors on the survival rate was analyzed with the Kaplan-Meier method and log-rank test. Multivariate analysis was assessed with Cox's regression model.ResultsThere were 148 males and 2 females, with a mean age of 53.5 years. The prevalence rate of habitual betel quid chewing documented in charts among 113 patients was 75%. The 5-year overall survival rate and disease-specific survival rate for all patients were 64% and 69%, respectively. For patients with stages I, II, III, and IV disease, the 5-year disease-specific survival rates were 90%, 77%, 52%, and 47%, respectively (p< 0.001). According to the multivariate analysis, the pathologic staging and histologic grading of the tumor were independently the important prognostic factors affecting survival rate. There were 80 patients who developed locoregional recurrence in lymph nodes in the follow-up diagnoses. Distant metastases occurred in 14 patients, with 11 of them also having locoregional recurrence. The distant metastases were found in the lungs (8/14), T-spine (3/14), liver (2/14) and brain (1/14).ConclusionPathologic stage and histologic grade are the most important prognostic factors

Validation of bidimensional measurement in nasopharyngeal carcinoma

<p>Abstract</p> <p>Background</p> <p>Our previous study showed a close relationship between computed tomography (CT)-derived bidimensional measurement of primary tumor and retropharyngeal nodes (BDMprn) and gross tumor volume of primary tumor and retropharyngeal nodes (GTVprn) in nasopharyngeal carcinoma (NPC) and better prognosis for NPC patients with smaller BDMprn. In this study, we report the results on of a study to validate the use of BDM in a separate cohort of NPC patients.</p> <p>Methods</p> <p>We retrospectively reviewed 103 newly diagnosed NPC cases who were treated with radiotherapy/concurrent chemoradiotherapy (CCRT) or CCRT with adjuvant chemotherapy from 2002 to 2009. We used magnetic resonance imaging (MRI) to measure BDMprn. We calculated overall survival, recurrence-free and distant metastasis-free survival curves and set a BDMprn cut off point to categorize patients into a high- or low-risk group. We then used Cox proportional hazard model to evaluate the prognostic influence of BDMprn after correcting age, gender and chemotherapy status.</p> <p>Results</p> <p>After adjusting for age, gender, and chemotherapy status, BDMprn remained an independent prognostic factor for distant metastasis [Hazard ratio (HR) = 1.046; <it>P </it>= 0.042] and overall survival (HR = 1.012; <it>P </it>= 0.012). Patients with BDMprn < 15 cm²had a greater 3-year overall survival rate than those with BDMprn ≧ 15 cm²(92.3% vs. 73.7%; <it>P </it>= 0.009). They also had a greater 3-year distant metastasis-free survival (94% vs.75%; <it>P </it>= 0.034).</p> <p>Conclusion</p> <p>The predictive ability of BDMprn was validated in a separate NPC cohort. A BDMprn of 15 cm²can be used to separate NPC patients into high- and low-risk groups and predict survival rates and metastasis potential. It can, therefore, be used as a reference to design clinical trials, predict prognosis, and make treatment decisions.</p

Serum tartrate-resistant acid phosphatase 5b activity as a prognostic marker of survival in breast cancer with bone metastasis

<p>Abstract</p> <p>Background</p> <p>Serum tartrate-resistant acid phosphatase 5b (TRACP 5b) activity is a marker of osteoclast number and is elevated in breast cancer (BC) patients with extensive bone metastasis, which might in turn reflect the tumour burden. We tested the hypothesis that baseline serum TRACP 5b activity and its interval change are potential prognostic markers of survival in BC patients with bone metastasis.</p> <p>Methods</p> <p>We analyzed the data from previous prospective studies. A total of 100 patients with newly diagnosed bone metastasis were included. Cox proportional regression model was used to evaluate the correlation between the overall survival time (OS) and baseline serum TRACP 5b activity and its interval changes. The least significant change (LSC) of TRACP 5b was calculated from data obtained from 15 patients with early BC.</p> <p>Results</p> <p>Estrogen receptor status (Hazard Ratio (HR) = 0.397; <it>p </it>= 0.003) and visceral metastasis (HR = 0.492; <it>p </it>= 0.0045) were significantly correlated with OS. The OS was significantly shorter in those patients with higher baseline TRACP 5b activity based on a cut-off value to delineate the highest tertile (HR = 3.524; <it>p </it>< 0.0001). Further analysis demonstrated that among patients in the highest tertile, OS was significantly longer in those patients who had achieved a decrease of serum TRACP 5b activity greater than the LSC (38.59%) (<it>p </it>= 0.0015).</p> <p>Conclusions</p> <p>We found that TRACP 5b activity and its interval change after treatment bore a prognostic role in BC patients with bone metastasis and a high baseline serum TRACP 5b activity. Further prospective phase II study is necessary to confirm these results.</p

Cognitive effects and tolerability of non-invasive brain stimulation on Alzheimer’s disease and mild cognitive impairment: a component network meta-analysis

Objectives: To compare cognitive effects and acceptability of repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS) in patients with Alzheimer’s disease (AD) or mild cognitive impairment (MCI), and to determine whether cognitive training (CT) during rTMS or tDCS provides additional benefits. Methods: Electronic search of PubMed, Medline, Embase, the Cochrane Library and PsycINFO up to 5 March 2020. We enrolled double-blind, randomised controlled trials (RCTs). The primary outcomes were acceptability and pre–post treatment changes in general cognition measured by Mini-Mental State Examination, and the secondary outcomes were memory function, verbal fluency, working memory and executive function. Durability of cognitive benefits (1, 2 and ≥3 months) after brain stimulation was examined. Results: We included 27 RCTs (n=1070), and the treatment components included high-frequency rTMS (HFrTMS) and low-frequency rTMS, anodal tDCS (atDCS) and cathodal tDCS (ctDCS), CT, sham CT and sham brain stimulation. Risk of bias of evidence in each domain was low (range: 0%–11.1%). HFrTMS (1.08, 9, 0.35–1.80) and atDCS (0.56, 0.03–1.09) had short-term positive effects on general cognition. CT might be associated with negative effects on general cognition (−0.79, –2.06 to 0.48) during rTMS or tDCS. At 1-month follow-up, HFrTMS (1.65, 0.77–2.54) and ctDCS (2.57, 0.20–4.95) exhibited larger therapeutic responses. Separate analysis of populations with pure AD and MCI revealed positive effects only in individuals with AD. rTMS and tDCS were well tolerated.\ud Conclusions: HFrTMS is more effective than atDCS for improving global cognition, and patients with AD may have better responses to rTMS and tDCS than MCI

Mortality rates in Alzheimer's disease and non-Alzheimer's dementias: a systematic review and meta-analysis

Background People with dementia die prematurely. Identifying differences in mortality rates between different types of dementia might aid in the development of preventive interventions for the most vulnerable populations. The aim of this study was to compare the difference in mortality rates between individuals without dementia and individuals with various types of dementia. Methods For this systematic review and meta-analysis, we did a systematic search of MEDLINE, PubMed, Embase, and Cochrane Library from inception to July 11, 2020, for cross-sectional or cohort studies that assessed mortality and survival-related outcomes among people with different types of dementia compared with people without dementia. Single-arm studies without comparison groups and autopsy studies or family studies that used a selected sample were excluded. The Newcastle-Ottawa Scale was used by two authors (D-JL and C-SC) independently to measure the methodological quality of included studies, and two authors (F-CY and P-TT) independently extracted data. We assessed differences in all-cause mortality rate and survival time from dementia diagnosis between individuals without dementia, individuals with Alzheimer's disease, and individuals with non-Alzheimer's disease dementias. The secondary outcomes were age at death and survival time from disease onset. Random-effects meta-analyses were done. Effect sizes included hazard ratios (HRs) and mean differences (MDs) with 95% CIs. Potential moderators, including age-associated moderators, were identified through meta-regression and subgroup analyses. This study is registered with PROSPERO, CRD42020198786. Findings Our database search identified 11 973 records, and we included 78 eligible studies in our analyses, encompassing 63 125 individuals with dementia and 152 353 controls. Individuals with any type of dementia had a higher mortality rate than individuals without dementia (HR 5·90, 95% CI 3·53 to 9·86), and the HR for all-cause mortality was highest for Lewy body dementia (17·88, 5·87 to 54·46). After diagnosis, the mean survival time for people with Alzheimer's disease was 5·8 years (SD 2·0). Compared with people with Alzheimer's disease, a diagnosis of any non-Alzheimer's disease dementia was associated with a higher risk of all-cause mortality (HR 1·33, 1·21 to 1·46), a shorter survival time from diagnosis (MD −1·12 years, 95% CI −1·52 to −0·72), and a younger age at death (−1·76 years, −2·66 to −0·85). Survival time from disease onset was also shorter in people with non-Alzheimer's dementia, across types, compared with people with Alzheimer's disease, but the subgroup analysis revealed that this difference was only significant for vascular dementia (MD −1·27 years, −1·90 to −0·65) and dementia with Lewy bodies (MD −1·06 years, −1·68 to −0·44). The interactions between age and several survival-related outcomes were significant. 39 (50%) of the 78 included studies were rated as good quality, and large heterogeneity (I2>75%) was observed for most of the study outcomes. Interpretation Alzheimer's disease is the most common type of dementia and one of the major causes of mortality worldwide. However, the findings from the current study suggest that non-Alzheimer's disease dementias were associated with higher morality rates and shorter life expectancy than Alzheimer's disease. Developing tailored treatment and rehabilitation programmes for different types of dementia is important for mental health providers, patients, and their families