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The spherical and dense alumina nanoparticles were used to prepare alumina microcrystalline ceramics. The effect of granulation and sintering parameters on the microstructure and mechanical properties of the ceramics was studied. The results show that fine green body can be obtained with the addition of 0.8% (mass fraction) PVA, and the density of green body can also be improved. With the increase of sintering temperature from 1400℃ to 1550℃, the density is increased from 74.1% to 97.5%, while the grain size of the ceramics is only increased gradually from 0.6 μm to 1.4 μm owing to the stable spherical shape and the uniformly packed pores. With the increase of holding time from 30 min to 120 min at 1550℃, the porosity is decreased from 4.8% to 0.4%, and the grain size is then increased from 1.2 μm to 2.7 μm. Besides, the sintering activation energy of the employed spheres is 788 kJ/mol, which proves that the particles are inactive during earlier and medium stage of sintering, and the spheres are benefit to obtain microcrystalline ceramics. The ceramic sintered at 1550℃ for 90 min has a density of 98.9%, an average grain size of 1.6 μm, a hardness of 26.4 GPa and a bending strength of 574 MPa.

The spherical and dense alumina nanoparticles were used to prepare alumina microcrystalline ceramics. The effect of granulation and sintering parameters on the microstructure and mechanical properties of the ceramics was studied. The results show that fine green body can be obtained with the addition of 0.8% (mass fraction) PVA, and the density of green body can also be improved. With the increase of sintering temperature from 1400℃ to 1550℃, the density is increased from 74.1% to 97.5%, while the grain size of the ceramics is only increased gradually from 0.6 μm to 1.4 μm owing to the stable spherical shape and the uniformly packed pores. With the increase of holding time from 30 min to 120 min at 1550℃, the porosity is decreased from 4.8% to 0.4%, and the grain size is then increased from 1.2 μm to 2.7 μm. Besides, the sintering activation energy of the employed spheres is 788 kJ/mol, which proves that the particles are inactive during earlier and medium stage of sintering, and the spheres are benefit to obtain microcrystalline ceramics. The ceramic sintered at 1550℃ for 90 min has a density of 98.9%, an average grain size of 1.6 μm, a hardness of 26.4 GPa and a bending strength of 574 MPa.

A good organization model of multiple mobile robot should be able to improve the efficiency of the system, reduce the complication of robot interactions, and detract the difficulty of computation. From the sociology aspect of topology, structure and organization, this paper studies the multiple mobile robot organization formation and running mechanism in the dynamic, complicated and unknown environment. It presents and describes in detail a HierarchicalWeb Recursive Organization Model (HWROM) and forming algorithm. It defines the robot society leader; robotic team leader and individual robot as the same structure by the united framework and describes the organization model by the recursive structure. The model uses task-oriented and top-down method to dynamically build and maintain structures and organization. It uses market-based techniques to assign task, form teams and allocate resources in dynamic environment. The model holds several characteristics of self-organization, dynamic, conciseness, commonness and robustness.

A good organization model of multiple mobile robot should be able to improve the efficiency of the system, reduce the complication of robot interactions, and detract the difficulty of computation. From the sociology aspect of topology, structure and organization, this paper studies the multiple mobile robot organization formation and running mechanism in the dynamic, complicated and unknown environment. It presents and describes in detail a Hierarchical-Web Recursive Organization Model (HWROM) and forming algorithm. It defines the robot society leader; robotic team leader and individual robot as the same structure by the united framework and describes the organization model by the recursive structure. The model uses task-oriented and top-down method to dynamically build and maintain structures and organization. It uses market-based techniques to assign task, form teams and allocate resources in dynamic environment. The model holds several characteristics of self-organization, dynamic, conciseness, commonness and robustness.

In this study, we aimed to establish the role of regenerating islet-derived family member 4 (Reg IV) as an independent risk factor and prognostic predictor in patients with T2-3 stage breast cancer who exhibit a non-pathological complete response (non-pCR) following neoadjuvant chemotherapy (NACT). Additionally, we examined the potential correlation and interaction between Reg IV and epidermal growth factor receptor (EGFR). Methods: A total of 67 patients with T2-3 stage breast cancer exhibiting non-pCR after NACT between September 2019 and December 2021 were included in this study. The analysis involved Kaplan–Meier survival comparisons, pooled hazard ratios for risk quantification, Cox regression analysis to isolate the impact of Reg IV on prognosis, Riskplots for visualizing risk profiles, and SHAP analysis to assess the importance of variables in predicting outcomes. Results: The findings indicate that patients positive for Reg IV had a significantly poorer prognosis (HR: 2.62, 95% CI: 1.06– 6.47). Co-expression of Reg IV and EGFR was associated with the worst outcomes compared to patients negative for both markers. Cox regression analysis confirmed the independent prognostic impact of Reg IV (HR: 2.63, 95% CI: 1.66– 3.59). Riskplot analysis showed that patients positive for both Reg IV and EGFR predominantly experienced disease progression. SHAP analysis further reinforced the significant effect of Reg IV on the disease course, without substantial interaction with EGFR. Conclusion: Reg IV may serve as an independent risk factor and predictive marker for adverse outcomes in patients with T2-3 stage breast cancer who do not achieve non-pCR following NACT. [ABSTRACT FROM AUTHOR]

Objectives: To analyse rates of avoidable mortality in Aboriginal and non-Aboriginal residents of the Northern Territory (NT) from 1985 to 2004, in order to assess the contribution of health care to life expectancy improvements. Methods: Australian Bureau of Statistics (ABS) death registration data for NT residents were used to identify 'avoidable' deaths, with further separation into three categories of conditions amenable to either medical care or health policy, and a category for ischaemic heart disease (IHD). A Poisson regression model was used to calculate the average annual change in avoidable mortality by sex and Aboriginality in the NT compared with Australia as a whole. Results: In the 20 years between 1985 and 2004, avoidable mortality rates fell 18.9% in NT Aboriginal people, 61.1% in NT non-Aboriginal people and 59.5% in Australians overall. NT Aboriginal people continued to experience higher avoidable mortality than other Australians and the disparity increased over time. Most of the decline in avoidable mortality for Aboriginal Territorians occurred for conditions amenable to medical care. Conclusion: Medical care has made a significant contribution to improvements in Aboriginal life expectancy in the NT, however, reductions in avoidable mortality from IHD and conditions amenable to health policy have been variable. Implications: The results highlight the need for ongoing investment in comprehensive programs incorporating appropriate health policy interventions and management of chronic diseases. Key words: avoidable mortality, Aboriginal health, Northern Territory, health care. Aust NZ J Public Health. 2009; 33:544-50 doi: 10.1111/j. 1753-6405.2009.00451.x

Objective: To assess trends in chronic disease mortality in the Aboriginal population of the Northern Territory (NT), using both underlying and multiple causes of death. Method: Death registration data from 1997 to 2004, were used for the analysis of deaths from five chronic diseases; ischaemic heart disease (IHD), diabetes, chronic obstructive pulmonary disease (COPD), renal failure and stroke. Negative binomial regression models were used to estimate the average annual change in mortality rates for each of the five diseases. Chi squared tests were conducted to determine associations between the five diseases. Results: The five chronic diseases contributed to 49.3% of all Aboriginal deaths in the NT. The mortality rate ratio of NT Aboriginal to all Australian death rates from each of the diseases ranged from 4.3 to 13.0, with the lowest rate ratio for stroke and highest for diabetes. There were significant statistical associations between IHD, diabetes, renal failure and stroke. The mortality rates for diabetes, COPD and stroke declined at estimated annual rates for NT Aboriginal males of 3.6%, 1.0% and 11.7% and for Aboriginal females by 3.5%, 6.1% and 7.1% respectively. There were increases in mortality rates for Aboriginal males and females for IHD and a mixed result for renal failure. Conclusion: NT Aboriginal people experience high chronic disease mortality, however, mortality rates appear to be declining for diabetes, COPD and stroke. The impact of chronic disease on mortality is greater than previously reported by using a single underlying cause of death. The results highlight the importance of integrated chronic disease interventions. Key words: chronic disease, mortality trend, Aboriginal health. Aust NZ J Public Health. 2009; 33:551-5 doi: 10.1111/j.1753-6405.2009.00452.x

Objectives: To assess concordance in reporting, in two Australian national datasets, of cause of death of patients with end-stage renal disease (ESRD). Methods: For deaths in 1997-99, we compared 'cause of death' and 'primary renal disease', as coded in the Australian and New Zealand Dialysis and Transplant Registry (ANZDATA), with 'underlying' and 'associated' causes of death (based on death certificates), as coded by the Australian Bureau of Statistics (ABS). Dates of birth and death and sex identified the same individuals in the two datasets. Deaths from the three States for which date of birth was not available from death certificates were excluded. Cause of death was compared at the ICD-10 chapter level. Results: Of 1,728 ANZDATA patients from NSW, SA, WA, NT and ACT who died during 1997-99, 1,117 (65%) could be matched to a record in the ABS dataset for the corresponding jurisdictions. The death certificates of 219 (20%) of these 1,117 patients made no mention of chronic renal failure. Overall, agreement on cause of death was poor (kappa=0.22). Using ANZDATA information on cause of death and ABS underlying cause of death, only 38% of patients had the same cause (at the ICD-10 chapter level) recorded in both datasets. Additional information on primary renal disease (ANZDATA) and up to 12 associated causes of death (ABS) was required to obtain substantial agreement. Conclusion and implications: Death certificates and ANZDATA records provide differing causes of death for ESRD patients. Information from these sources was not directly comparable. Neither dataset provided a complete picture of renal disease as a cause of death in Australia.